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Switch unit tests to testify

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This commit is contained in:
James Coleman 2026-07-01 17:51:41 -05:00
parent 50a535bb7f
commit 2ddcecb924
35 changed files with 3465 additions and 1365 deletions
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90
README.md
View file

@ -37,14 +37,14 @@ backend is logged but does not abort the others.
**Network configuration (persistence)**
| Backend | Detection |
| ------------------- | ------------------------------------------- |
| netplan | `netplan` binary on `PATH` |
| cloud-init | cloud-init network config present |
| NetworkManager | `NetworkManager.service` active |
| systemd-networkd | `systemd-networkd.service` active |
| RHEL network-scripts| `network.service` active (config dir on legacy hosts) |
| ifupdown | `/etc/network/interfaces` |
| Backend | Detection |
| ------------------- | ----------------------------------------------------- |
| netplan | `netplan` binary on `PATH`, and `netplan info` succeeds |
| cloud-init | cloud-init network config present |
| NetworkManager | `NetworkManager` service running or enabled, or its pid file present |
| systemd-networkd | `systemd-networkd` service running or enabled |
| RHEL network-scripts| `network` service running or enabled |
| ifupdown | `/etc/network/interfaces`, and the `networking` service running or enabled |
**Control panels**
@ -54,11 +54,12 @@ backend is logged but does not abort the others.
| Plesk | `/usr/sbin/plesk` |
| InterWorx | `/usr/bin/nodeworx` |
Detection of the service-managed backends (NetworkManager, systemd-networkd,
and RHEL network-scripts) uses systemd over D-Bus, with a fallback for legacy
systems that lack a usable systemd D-Bus interface (Ubuntu 14.04 Upstart,
CentOS 5/6). On that fallback path network-scripts is detected by the presence
of its `/etc/sysconfig/network-scripts` directory.
### How service-managed backends are detected
A service counts as managing the network when it is **running now** or
**enabled to start at boot**. Enablement matters on its own: this library writes
configuration that must survive a reboot, and a manager that is enabled but not
yet started still owns the network after the next boot.
## Platforms
@ -71,7 +72,7 @@ of its `/etc/sysconfig/network-scripts` directory.
```go
type Configurator interface {
// Enumerate interfaces with their addresses, gateways, static routes,
// DNS servers, and search domains.
// DNS servers, search domains, and DHCP client state.
GetInterfaces(ctx context.Context) ([]*Interface, error)
// Add an IP address (optionally setting/replacing the default gateway).
@ -89,15 +90,23 @@ type Configurator interface {
// Set the DNS servers and search domains for an interface.
SetDNS(ctx context.Context, iface string, servers []net.IP, searchDomains []string) error
// Turn each address family's DHCP client on or off.
SetDHCP(ctx context.Context, iface string, dhcp4, dhcp6 bool) error
}
// Construct the configurator for the current OS, auto-detecting backends.
// Behaviour is tuned with Option values (see Options below).
func NewConfigurator(opts ...Option) (Configurator, error)
// ctx bounds the detection; behaviour is tuned with Option values (see
// Options below).
func NewConfigurator(ctx context.Context, opts ...Option) (Configurator, error)
// Resolve an interface by name, or by the special "public-internet" /
// "public-internet-6" selectors.
func FindInterfaceByName(name string, ifaces []*Interface) *Interface
// Filter to the hardware-backed interfaces, best candidate for internet
// configuration first.
func FindPhysicalInterfaces(ifaces []*Interface) []*Interface
```
Every operation takes a `context.Context`. The slow steps — the ICMP probe of a
@ -110,6 +119,16 @@ deadlines, so a caller can bound how long a change may block.
resolver so they take effect immediately, and persists them through whichever
network management backends are detected on the host so they survive a reboot.
### DHCP
`SetDHCP` turns each address family's DHCP client on or off independently —
moving an interface to DHCPv4 while keeping a static IPv6 address is
`SetDHCP(ctx, "eth0", true, false)`. Enabling a family acquires a lease now
through the detected manager; disabling only rewrites the configuration, leaving
an existing lease to expire so a caller connected over the leased address is not
cut off. `AddAddress` never changes DHCP state — it adds static addresses only.
`Interface.DHCP4` and `Interface.DHCP6` report the state back.
### Logging
The package uses a single, package-wide logger for non-fatal diagnostics from
@ -125,7 +144,7 @@ netconfig.SetLogger(myLogger) // anything with Printf/Println, e.g. *log.Logger
`NewConfigurator` accepts functional options:
```go
c, err := netconfig.NewConfigurator(
c, err := netconfig.NewConfigurator(ctx,
netconfig.WithTestAddress("http://my-canary/health"), // connectivity-test URL
netconfig.WithConnectivityCheck(false), // skip the post-change probe + rollback
netconfig.WithSkipConnectivityCheck(), // same as WithConnectivityCheck(false)
@ -135,6 +154,8 @@ c, err := netconfig.NewConfigurator(
netconfig.WithBackupRetention(10), // .bak.* copies kept per config file (0 = keep all)
netconfig.WithAllowPrimaryRemoval(true), // let RemoveAddress remove the primary IP
netconfig.WithSkipPanels(true), // skip all panel interaction (add/primary/remove)
netconfig.WithAllowNoBackends(true), // don't fail when no persistence backend is detected
netconfig.WithServiceReadyTimeout(90 * time.Second), // how long to wait for a daemon-backed backend (default 60s, 0 = don't wait)
)
```
@ -155,12 +176,45 @@ the override only when you are deliberately tearing down the current primary.
InterWorx to reload, set the main IP, or release an IP. Only the running system
and the network-manager configuration files are changed.
### Choosing an interface
`FindInterfaceByName` accepts two well-known selectors in addition to a literal
interface name:
- `"public-internet"` — the interface that carries the IPv4 default gateway.
- `"public-internet-6"` — the interface that carries the IPv6 default gateway.
Those answer "which interface is already on the internet". When the host is not
on the internet yet — a freshly provisioned VM, an image whose NIC name is not
known in advance — `FindPhysicalInterfaces` answers "which interface should be".
It drops the devices that should never carry a public address (bridges, bonds,
VLANs, tunnels, container veth pairs) and returns what is left in the order a
caller should try them:
1. Interfaces that are up, before those that are down.
2. Interfaces already carrying a default gateway, IPv4 ahead of IPv6-only.
3. Wired ahead of wireless.
4. By name as a person reads it, so `eth0` precedes `eth1` and `eth2`
precedes `eth10`.
Paravirtual NICs (virtio, vmxnet, Xen) count as physical: a VM's only real
interface is still the one to configure. The result is a ranking, not a
decision — a caller with a further requirement, such as an interface not already
holding a public address, filters the slice and takes the first survivor:
```go
ifaces, err := c.GetInterfaces(ctx)
for _, iface := range netconfig.FindPhysicalInterfaces(ifaces) {
if !hasPublicAddress(iface) {
return iface.Name
}
}
```
`Interface.Up` and `Interface.Physical` carry the two facts this ranking rests
on, and are readable on their own. Both describe the running system, so they are
only set by `GetInterfaces`.
## Usage
```go
@ -177,7 +231,7 @@ import (
func main() {
ctx := context.Background()
c, err := netconfig.NewConfigurator()
c, err := netconfig.NewConfigurator(ctx)
if err != nil {
log.Fatal(err)
}

118
cloudinit.go
View file

@ -65,6 +65,31 @@ type ciInterface struct {
Optional bool `yaml:"optional,omitempty" json:"optional,omitempty"`
}
// dhcpState reports whether each family's DHCP client is enabled. An absent key
// means the schema default, which is off.
func (c *ciInterface) dhcpState() (dhcp4, dhcp6 bool) {
return c.DHCP4 != nil && *c.DHCP4, c.DHCP6 != nil && *c.DHCP6
}
// setDHCP records the requested DHCP client state for both families, dropping
// the overrides of a family whose client is being turned off. A family being
// disabled that was already absent stays absent rather than being written out
// as false.
func (c *ciInterface) setDHCP(dhcp4, dhcp6 bool) {
if dhcp4 || c.DHCP4 != nil {
c.DHCP4 = boolPtr(dhcp4)
}
if !dhcp4 {
c.DHCP4Overrides = nil
}
if dhcp6 || c.DHCP6 != nil {
c.DHCP6 = boolPtr(dhcp6)
}
if !dhcp6 {
c.DHCP6Overrides = nil
}
}
// Physical ethernet interface.
type ciEthernet struct {
ciPhysical `yaml:",inline" json:",inline"`
@ -375,6 +400,7 @@ func (*cloudInit) ConvertInterface(name string, MAC string, config ciInterface,
i.Name = name
i.MAC = mac
i.Link = foundLink
i.DHCP4, i.DHCP6 = config.dhcpState()
// Parse addresses.
for _, addr := range config.Addresses {
@ -473,6 +499,15 @@ func (ci *cloudInit) GetInterfaces() (interfaces []*Interface, err error) {
// Parse subnet configs.
for _, subnet := range config.Subnets {
// A v1 subnet encodes the DHCP client in its type rather than in a
// dhcp4/dhcp6 key. "dhcp" with no suffix is the IPv4 client.
switch subnet.Type {
case "dhcp", "dhcp4":
i.DHCP4 = true
case "dhcp6", "ipv6_dhcpv6-stateful", "ipv6_dhcpv6-stateless":
i.DHCP6 = true
}
// Add DNS servers and search domains.
for _, dns := range subnet.DNSNameservers {
if ip := net.ParseIP(dns); ip != nil {
@ -1024,6 +1059,89 @@ func (ci *cloudInit) SetIfaceAddresses(_ context.Context, iface string, addrs []
return
}
// ciDHCPSubnetTypes are the v1 subnet types that describe a DHCP client rather
// than a static address, keyed by whether they are removed when that family's
// client is disabled.
var ciDHCPSubnetTypes = map[string]bool{
"dhcp": true, // IPv4, the unsuffixed spelling.
"dhcp4": true,
"dhcp6": false,
"ipv6_dhcpv6-stateful": false,
"ipv6_dhcpv6-stateless": false,
}
// Set the DHCP client state on an interface.
func (ci *cloudInit) SetIfaceDHCP(_ context.Context, iface string, dhcp4, dhcp6 bool) (err error) {
// Apply changes to v1 configs, where the DHCP client is a subnet whose type
// names it rather than a key. Static subnets are left in place: cloud-init
// accepts a dhcp subnet and a static subnet on the same interface.
for c, config := range ci.Network.Configs {
switch config.Type {
case "physical", "bond", "bridge", "vlan":
default:
continue
}
if config.Name != iface {
continue
}
// Drop the existing DHCP subnets of both families, then re-add the ones
// that were asked for. Rebuilding rather than editing in place keeps a
// config that listed several spellings of the same client from ending up
// with a stale one alongside the new one.
subnets := make([]ciSubnet, 0, len(config.Subnets)+2)
if dhcp4 {
subnets = append(subnets, ciSubnet{Type: "dhcp4"})
}
if dhcp6 {
subnets = append(subnets, ciSubnet{Type: "dhcp6"})
}
for _, subnet := range config.Subnets {
if _, isDHCP := ciDHCPSubnetTypes[subnet.Type]; isDHCP {
continue
}
subnets = append(subnets, subnet)
}
config.Subnets = subnets
ci.Network.Configs[c] = config
}
// Apply changes to v2 ethernets.
for name, config := range ci.Network.Ethernets {
ifName := name
if config.SetName != "" {
ifName = config.SetName
}
if ifName != iface {
continue
}
config.setDHCP(dhcp4, dhcp6)
ci.Network.Ethernets[name] = config
}
// Apply changes to v2 bridges.
if config, ok := ci.Network.Bridges[iface]; ok {
config.setDHCP(dhcp4, dhcp6)
ci.Network.Bridges[iface] = config
}
// Apply changes to v2 bonds.
if config, ok := ci.Network.Bonds[iface]; ok {
config.setDHCP(dhcp4, dhcp6)
ci.Network.Bonds[iface] = config
}
// Apply changes to v2 VLAN interfaces.
if config, ok := ci.Network.VLANs[iface]; ok {
config.setDHCP(dhcp4, dhcp6)
ci.Network.VLANs[iface] = config
}
// Try to save changes.
err = ci.Save()
return
}
// Set static routes to interface.
func (ci *cloudInit) SetIfaceRoutes(_ context.Context, iface string, routes []*Route) (err error) {
// Apply changes to v1 configs.

138
cloudinit_test.go
View file

@ -6,43 +6,33 @@ import (
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/require"
)
// Validate the cloud-init configuration parser/writer functions.
func TestCloudinit(t *testing.T) {
// Setup test file.
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
configPath := filepath.Join(tmpDir, "network.yaml")
testDir, err := filepath.Abs("./tests/cloudinit")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
err = fileCopy(filepath.Join(testDir, "network.yaml"), configPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup ifupdown and parse test file.
ci, err := newCloudInitWith(configPath, filepath.Join(tmpDir, "nothing.json"), filepath.Join(tmpDir, "cloud.cfg.d"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err := ci.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = ci.SetIfaceAddresses(context.Background(), "test_eth0.1556", []*net.IPNet{
@ -59,9 +49,7 @@ func TestCloudinit(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("1.2.3.1"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = ci.SetIfaceRoutes(context.Background(), "test_eth3", []*Route{
@ -82,27 +70,19 @@ func TestCloudinit(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = ci.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = ci.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -111,76 +91,52 @@ func TestCloudinit(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = ci.SetIfaceRoutes(context.Background(), "test_eth0.1556", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = ci.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}
// Validate the cloudbase-init configuration parser/writer functions.
func TestCloudbaseinit(t *testing.T) {
// Setup test file.
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
configPath := filepath.Join(tmpDir, "network.json")
testDir, err := filepath.Abs("./tests/cloudinit/cloudbase")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
err = fileCopy(filepath.Join(testDir, "network.json"), configPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup ifupdown and parse test file.
ci, err := newCloudInitWith(filepath.Join(tmpDir, "nothing.yaml"), configPath, filepath.Join(tmpDir, "cloud.cfg.d"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err := ci.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = ci.SetIfaceAddresses(context.Background(), "test_eth0.1556", []*net.IPNet{
@ -197,9 +153,7 @@ func TestCloudbaseinit(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("1.2.3.1"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = ci.SetIfaceRoutes(context.Background(), "test_eth3", []*Route{
@ -220,27 +174,19 @@ func TestCloudbaseinit(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = ci.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = ci.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -249,37 +195,25 @@ func TestCloudbaseinit(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = ci.SetIfaceRoutes(context.Background(), "test_eth0.1556", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = ci.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}

207
configurator_linux.go
View file

@ -6,9 +6,7 @@ import (
"fmt"
"net"
"os"
"os/exec"
dbus "github.com/coreos/go-systemd/dbus"
"github.com/vishvananda/netlink"
)
@ -21,86 +19,83 @@ type linuxConfigurator struct {
*configOptions
}
// Returns the linux network configurator. Behaviour is tuned with Option
// values such as WithTestAddress and WithConnectivityCheck; use SetLogger to
// replace the package-wide logger.
func NewConfigurator(opts ...Option) (configurator Configurator, err error) {
// Returns the linux network configurator. Backends are auto-detected; ctx
// bounds that detection, which queries systemd over D-Bus and may shell out to
// chkconfig and netplan. Behaviour is tuned with Option values such as
// WithTestAddress and WithConnectivityCheck; use SetLogger to replace the
// package-wide logger.
func NewConfigurator(ctx context.Context, opts ...Option) (Configurator, error) {
options := newConfigOptions(opts...)
// Connect to dbus for systemd and list active units to determine which
// network managers are running. This fails on systems without a usable
// systemd D-Bus interface, so we fall back to detecting legacy managers:
// - Ubuntu 14.04: Upstart is PID 1 and org.freedesktop.systemd1 is served
// by systemd-shim, which lacks ListUnits ("No such method 'ListUnits'").
// - CentOS 5/6: no systemd1 on the bus at all, so ListUnits (or the
// connection itself) fails with ServiceUnknown.
activeUnits := make(map[string]bool)
conn, derr := dbus.NewWithContext(context.Background())
if derr == nil {
defer conn.Close()
var units []dbus.UnitStatus
units, derr = conn.ListUnitsContext(context.Background())
for _, unit := range units {
if unit.ActiveState == "active" {
activeUnits[unit.Name] = true
}
}
}
if derr != nil {
logger.Printf("unable to list systemd units, falling back to legacy detection: %v", derr)
activeUnits = legacyActiveUnits()
}
// Determine candidates based on unit status.
// Snapshot what the init system knows about its units once. Every backend
// check below is answered from it, falling back to the SysV mechanisms for
// any service systemd cannot speak for.
initSys := newInitState(ctx)
c := new(linuxConfigurator)
c.configOptions = options
configurator = c
// Detect each backend. A nil concrete pointer wrapped in an interface is
// itself non-nil, so backends are collected as concrete pointers here and
// only registered below when non-nil.
// only registered below when non-nil. Each constructor's error is kept local:
// a backend that fails to parse is skipped, not fatal, and must not leak into
// the error returned to the caller.
var (
nd *networkd
nm *networkManager
ns *networkScripts
iud *ifUpDown
np *netplan
ci *cloudInit
)
if activeUnits["systemd-networkd.service"] {
nd, err = newNetworkd(options.backupRetention)
if err != nil {
if initSys.detected(ctx, "systemd-networkd") {
var err error
if nd, err = newNetworkd(options.backupRetention); err != nil {
logger.Println("error parsing networkd config:", err)
}
}
if activeUnits["NetworkManager.service"] {
nm, err = newNetworkManager()
if err != nil {
// NetworkManager's pid file is checked as well as its unit, so the daemon is
// still found on a host whose systemd could not be queried. Detection here
// includes a unit that is enabled but not yet started, so newNetworkManager
// waits for the daemon to reach the bus and finish starting: this program
// may be run early enough in boot to beat it, and NetworkManager is
// configured through that daemon rather than through a file.
if initSys.detected(ctx, "NetworkManager") || networkManagerRunning() {
var err error
if nm, err = newNetworkManager(ctx, options.serviceReadyTimeout); err != nil {
logger.Println("error parsing network manager config:", err)
}
}
if activeUnits["network.service"] {
ns, err = newNetworkScripts(options.backupRetention)
if err != nil {
// The RHEL-family network-scripts service. newNetworkScripts returns an error
// when /etc/sysconfig/network-scripts is absent, so a host that has the
// service registered but no scripts directory registers no backend.
if initSys.detected(ctx, "network") {
var err error
if ns, err = newNetworkScripts(options.backupRetention); err != nil {
logger.Println("error parsing network scripts:", err)
}
}
// If the ifupdown config exists, add its config.
if _, serr := os.Stat(ifUpDownConfig); serr == nil {
iud, err = newIfUpDown(options.backupRetention)
if err != nil {
logger.Println("error prasing ifupdown:", err)
if ifUpDownDetected(ctx, initSys) {
var err error
if iud, err = newIfUpDown(options.backupRetention); err != nil {
logger.Println("error parsing ifupdown:", err)
}
}
_, err = exec.LookPath("netplan")
if err == nil {
np, err = newNetplan(options.backupRetention)
if err != nil {
// netplan is gated on its binary resolving before newNetplan runs `netplan
// info`, so a host without netplan pays no subprocess and logs no failure.
if commandExists("netplan") {
var err error
if np, err = newNetplan(ctx, options.backupRetention); err != nil {
logger.Println("error parsing netplan:", err)
}
}
ci, err = newCloudInit(options.backupRetention)
// cloud-init has no service to detect: it runs once at boot and is found by
// its configuration alone, which newCloudInit reports on.
ci, err := newCloudInit(options.backupRetention)
if err != nil {
logger.Println("error parsing cloud-init:", err)
}
@ -126,6 +121,21 @@ func NewConfigurator(opts ...Option) (configurator Configurator, err error) {
c.ifaceBackends = append(c.ifaceBackends, namedIfaceBackend{"IfUpDown", iud})
}
// A host with no file backend can still have its running state changed through
// netlink, but nothing would persist and the change would vanish on the next
// boot. Fail here rather than hand back a configurator that silently writes
// nowhere; WithAllowNoBackends opts into it for read-only callers.
if len(c.ifaceBackends) == 0 {
// A cancelled context aborts every probe above, which looks identical to
// a host that genuinely has no backend. Report the real cause.
if cerr := ctx.Err(); cerr != nil {
return nil, fmt.Errorf("backend detection did not complete: %w", cerr)
}
if !options.allowNoBackends {
return nil, fmt.Errorf("no network configuration backend detected: address changes would apply to the running system but not survive a reboot (use WithAllowNoBackends to proceed anyway)")
}
}
// Register the detected control panels in a stable apply order.
if _, serr := os.Stat(cpanelBin); serr == nil {
c.panelBackends = append(c.panelBackends, namedPanelBackend{"cPanel", new(cpanel)})
@ -137,44 +147,46 @@ func NewConfigurator(opts ...Option) (configurator Configurator, err error) {
c.panelBackends = append(c.panelBackends, namedPanelBackend{"Interworx", new(interworx)})
}
// Detection failures are logged above; they are not fatal to constructing
// the configurator, so do not propagate them to the caller.
err = nil
return
// Detection failures are logged above; a backend that could not be parsed is
// skipped rather than propagated, so the configurator is returned without an
// error as long as at least one backend was registered.
return c, nil
}
// legacyActiveUnits detects active network managers on systems that lack a
// usable systemd D-Bus interface, where ListUnits is unavailable: Upstart on
// Ubuntu 14.04 and SysVinit/Upstart on CentOS 5/6. Detection is by config and
// runtime presence rather than by querying any specific init system, so it is
// init-agnostic and spawns no subprocesses.
//
// systemd-networkd cannot run on these systems, and ifupdown is detected
// separately by config-file presence, so only the RHEL network-scripts service
// and NetworkManager are considered here. The returned keys match the systemd
// unit names used by the caller.
func legacyActiveUnits() map[string]bool {
active := make(map[string]bool)
// RHEL-family network-scripts has no daemon; presence of its config
// directory is the best available signal that it manages the network.
if fi, serr := os.Stat(networkScriptsPath); serr == nil && fi.IsDir() {
active["network.service"] = true
// ifUpDownDetected reports whether ifupdown manages this host's network.
// /etc/network/interfaces existing is not enough on its own: it is left behind
// on Ubuntu hosts migrated to netplan and on Debian hosts that have handed the
// network to NetworkManager, so the networking service must also be running or
// enabled. On a host with no discoverable init system there is nothing to
// corroborate against, and the config file's presence is taken as sufficient
// rather than dropping a backend that may well be the only one.
func ifUpDownDetected(ctx context.Context, s *initState) bool {
if _, err := os.Stat(ifUpDownConfig); err != nil {
return false
}
return s.detected(ctx, "networking") || !initSystemDiscoverable()
}
// NetworkManager manages the network via its own D-Bus interface; a
// runtime pid file indicates the daemon is running.
for _, pidFile := range []string{
"/var/run/NetworkManager/NetworkManager.pid",
"/run/NetworkManager/NetworkManager.pid",
} {
if _, serr := os.Stat(pidFile); serr == nil {
active["NetworkManager.service"] = true
break
}
// linkIsUp reports whether a link can carry traffic. The operational state is
// the honest answer where the driver reports one: an interface that is
// administratively up but has no carrier — an unplugged cable — cannot. Many
// virtual and paravirtual drivers never report an operational state at all, so
// for those the administrative flag stands in.
func linkIsUp(attrs *netlink.LinkAttrs) bool {
if attrs.OperState == netlink.OperUnknown {
return attrs.Flags&net.FlagUp != 0
}
return attrs.OperState == netlink.OperUp
}
return active
// linkIsPhysical reports whether a link is backed by a network device rather
// than created by the kernel. rtnetlink names the kind of every software
// device — bridge, bond, veth, vlan, tun, wireguard, dummy — and names no kind
// at all for a driver-backed NIC, which is the "device" this compares against.
// Paravirtual NICs (virtio, vmxnet, xen) are driver-backed and so count as
// physical: a VM's only real NIC is still the one to configure.
func linkIsPhysical(link netlink.Link) bool {
return link.Type() == "device"
}
// Get list of interfaces and their configs.
@ -206,6 +218,8 @@ func (c *linuxConfigurator) GetInterfaces(ctx context.Context) (interfaces []*In
i.Name = link.Attrs().Name
i.MAC = link.Attrs().HardwareAddr
i.Link = link
i.Up = linkIsUp(link.Attrs())
i.Physical = linkIsPhysical(link)
// Add IP Addresses.
addrs, err := h.AddrList(link, netlink.FAMILY_ALL)
@ -261,10 +275,11 @@ func (c *linuxConfigurator) GetInterfaces(ctx context.Context) (interfaces []*In
interfaces = append(interfaces, i)
}
// DNS servers and search domains are not exposed via netlink, so merge
// them in from the persisted backend configurations. This lets callers
// read back what SetDNS wrote via Interface.DNS and Interface.SearchDomains.
mergeDNSFromBackends(c.ifaceBackends, interfaces)
// DNS servers, search domains, and DHCP client state are not exposed via
// netlink, so merge them in from the persisted backend configurations. This
// lets callers read back what SetDNS and SetDHCP wrote via Interface.DNS,
// Interface.SearchDomains, Interface.DHCP4, and Interface.DHCP6.
mergeBackendState(c.ifaceBackends, interfaces)
return
}
@ -1016,3 +1031,19 @@ func (c *linuxConfigurator) SetDNS(ctx context.Context, iface string, servers []
applyLiveDNS(ctx, iface, servers, searchDomains)
return nil
}
// Enable or disable the DHCP client for each address family on an interface.
func (c *linuxConfigurator) SetDHCP(ctx context.Context, iface string, dhcp4, dhcp6 bool) error {
if !applyIfaceDHCP(ctx, c.ifaceBackends, iface, dhcp4, dhcp6) {
return fmt.Errorf("no backend accepted a DHCP change for %s", iface)
}
// Enabling a client asks the running system to acquire a lease now. Turning
// one off does not reconfigure the interface: the existing lease is left to
// expire, so a caller connected over the leased address is not cut off by a
// call that was only meant to change what happens on the next boot.
if dhcp4 || dhcp6 {
renewDHCPOnBackends(ctx, c.ifaceBackends, iface)
}
return nil
}

318
configurator_linux_test.go
View file

@ -6,9 +6,10 @@ import (
"os"
"path/filepath"
"runtime"
"strings"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"github.com/vishvananda/netlink"
"github.com/vishvananda/netns"
"golang.org/x/sys/unix"
@ -24,18 +25,12 @@ func setupNetlinkTest(t testing.TB) func() {
runtime.LockOSThread()
ns, err := netns.New()
if err != nil {
t.Fatal("Failed to create new netns", err)
}
require.NoError(t, err, "Failed to create new netns")
link, err := netlink.LinkByName("lo")
if err != nil {
t.Fatalf("Failed to find \"lo\" in new netns: %v", err)
}
require.NoError(t, err, "Failed to find \"lo\" in new netns")
err = netlink.LinkSetUp(link)
if err != nil {
t.Fatalf("Failed to bring up \"lo\" in new netns: %v", err)
}
require.NoError(t, err, "Failed to bring up \"lo\" in new netns")
return func() {
ns.Close()
@ -49,9 +44,7 @@ func setupNetlinkTest(t testing.TB) func() {
func isPrimary(t testing.TB, h *netlink.Handle, link netlink.Link, ip net.IP) (present, primary bool) {
t.Helper()
addrs, err := h.AddrList(link, netlink.FAMILY_ALL)
if err != nil {
t.Fatalf("AddrList: %v", err)
}
require.NoError(t, err, "AddrList")
for _, a := range addrs {
if a.IPNet.IP.Equal(ip) {
return true, a.Flags&unix.IFA_F_SECONDARY == 0
@ -68,9 +61,7 @@ func TestLinuxSetPrimaryAddress(t *testing.T) {
defer tearDown()
h, err := netlink.NewHandle()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
defer h.Close()
// Setup test link.
@ -79,42 +70,30 @@ func TestLinuxSetPrimaryAddress(t *testing.T) {
Name: name,
HardwareAddr: net.HardwareAddr{0x52, 0x54, 0x00, 0x8b, 0x0d, 0x93},
}})
if err = h.LinkAdd(link); err != nil {
t.Fatal(err)
}
if err = h.LinkSetUp(link); err != nil {
t.Fatal(err)
}
require.NoError(t, h.LinkAdd(link))
require.NoError(t, h.LinkSetUp(link))
// Add two addresses in the same subnet. The first added is the primary.
primaryIP := &net.IPNet{IP: net.ParseIP("1.2.3.4"), Mask: net.CIDRMask(24, 32)}
secondaryIP := &net.IPNet{IP: net.ParseIP("1.2.3.5"), Mask: net.CIDRMask(24, 32)}
if err = h.AddrAdd(link, &netlink.Addr{IPNet: primaryIP}); err != nil {
t.Fatal(err)
}
if err = h.AddrAdd(link, &netlink.Addr{IPNet: secondaryIP}); err != nil {
t.Fatal(err)
}
require.NoError(t, h.AddrAdd(link, &netlink.Addr{IPNet: primaryIP}))
require.NoError(t, h.AddrAdd(link, &netlink.Addr{IPNet: secondaryIP}))
// Add a default route via the subnet so connectivity verification has a
// gateway to work with.
gw := net.ParseIP("1.2.3.1")
if err = h.RouteAdd(&netlink.Route{
require.NoError(t, h.RouteAdd(&netlink.Route{
Family: netlink.FAMILY_V4,
LinkIndex: link.Attrs().Index,
Dst: &net.IPNet{IP: net.IPv4zero, Mask: net.CIDRMask(0, 32)},
Gw: gw,
}); err != nil {
t.Fatal(err)
}
}))
// Sanity check the initial primary/secondary assignment.
if _, primary := isPrimary(t, h, link, primaryIP.IP); !primary {
t.Fatal("expected 1.2.3.4 to start as primary")
}
if _, primary := isPrimary(t, h, link, secondaryIP.IP); primary {
t.Fatal("expected 1.2.3.5 to start as secondary")
}
_, primary := isPrimary(t, h, link, primaryIP.IP)
require.True(t, primary, "expected 1.2.3.4 to start as primary")
_, primary = isPrimary(t, h, link, secondaryIP.IP)
require.False(t, primary, "expected 1.2.3.5 to start as secondary")
// Configurator with the success sentinel and a capturing backend.
backend := &fakeIfaceBackend{}
@ -122,51 +101,36 @@ func TestLinuxSetPrimaryAddress(t *testing.T) {
c.ifaceBackends = append(c.ifaceBackends, namedIfaceBackend{"fake", backend})
// Promote the secondary to primary.
if err = c.SetPrimaryAddress(context.Background(), name, secondaryIP); err != nil {
t.Fatalf("SetPrimaryAddress: %v", err)
}
require.NoError(t, c.SetPrimaryAddress(context.Background(), name, secondaryIP), "SetPrimaryAddress")
// The kernel should now treat 1.2.3.5 as primary and 1.2.3.4 as secondary,
// with both addresses still present and the default route intact.
if present, primary := isPrimary(t, h, link, secondaryIP.IP); !present || !primary {
t.Errorf("after promotion 1.2.3.5: present=%v primary=%v, want both true", present, primary)
}
if present, primary := isPrimary(t, h, link, primaryIP.IP); !present || primary {
t.Errorf("after promotion 1.2.3.4: present=%v primary=%v, want present true primary false", present, primary)
}
present, primary := isPrimary(t, h, link, secondaryIP.IP)
assert.True(t, present && primary, "after promotion 1.2.3.5: present=%v primary=%v, want both true", present, primary)
present, primary = isPrimary(t, h, link, primaryIP.IP)
assert.True(t, present && !primary, "after promotion 1.2.3.4: present=%v primary=%v, want present true primary false", present, primary)
routes, err := h.RouteList(link, netlink.FAMILY_V4)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
haveDefault := false
for _, r := range routes {
if ones, _ := r.Dst.Mask.Size(); ones == 0 && r.Gw.Equal(gw) {
haveDefault = true
}
}
if !haveDefault {
t.Error("default route missing after promotion")
}
assert.True(t, haveDefault, "default route missing after promotion")
// The persisted config must receive the reordered list, primary first.
if len(backend.lastAddrs) == 0 || !backend.lastAddrs[0].IP.Equal(secondaryIP.IP) {
t.Errorf("backend primary = %v, want 1.2.3.5 first", backend.lastAddrs)
}
assert.True(t, len(backend.lastAddrs) != 0 && backend.lastAddrs[0].IP.Equal(secondaryIP.IP), "backend primary = %v, want 1.2.3.5 first", backend.lastAddrs)
// Promoting the already-primary address is a no-op that still succeeds.
if err = c.SetPrimaryAddress(context.Background(), name, secondaryIP); err != nil {
t.Errorf("SetPrimaryAddress (idempotent): %v", err)
}
if _, primary := isPrimary(t, h, link, secondaryIP.IP); !primary {
t.Error("1.2.3.5 should remain primary after idempotent call")
}
assert.NoError(t, c.SetPrimaryAddress(context.Background(), name, secondaryIP), "SetPrimaryAddress (idempotent)")
_, primary = isPrimary(t, h, link, secondaryIP.IP)
assert.True(t, primary, "1.2.3.5 should remain primary after idempotent call")
// Promoting an address not on the interface must error before any change.
absent := &net.IPNet{IP: net.ParseIP("1.2.3.99"), Mask: net.CIDRMask(24, 32)}
err = c.SetPrimaryAddress(context.Background(), name, absent)
if err == nil || err.Error() != "address not found on interface" {
t.Errorf("absent address error = %v, want \"address not found on interface\"", err)
}
assert.EqualError(t, err, "address not found on interface")
}
// TestLinuxRemovePrimaryRefused verifies that RemoveAddress refuses to remove
@ -177,43 +141,27 @@ func TestLinuxRemovePrimaryRefused(t *testing.T) {
defer tearDown()
h, err := netlink.NewHandle()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
defer h.Close()
name := "test_enp1s0"
link := netlink.Link(&netlink.Dummy{LinkAttrs: netlink.LinkAttrs{Name: name}})
if err = h.LinkAdd(link); err != nil {
t.Fatal(err)
}
if err = h.LinkSetUp(link); err != nil {
t.Fatal(err)
}
require.NoError(t, h.LinkAdd(link))
require.NoError(t, h.LinkSetUp(link))
primaryIP := &net.IPNet{IP: net.ParseIP("1.2.3.4"), Mask: net.CIDRMask(24, 32)}
if err = h.AddrAdd(link, &netlink.Addr{IPNet: primaryIP}); err != nil {
t.Fatal(err)
}
require.NoError(t, h.AddrAdd(link, &netlink.Addr{IPNet: primaryIP}))
c := &linuxConfigurator{configOptions: &configOptions{testAddress: "test_success"}}
c.ifaceBackends = append(c.ifaceBackends, namedIfaceBackend{"fake", &fakeIfaceBackend{}})
// Default: removing the primary is refused.
err = c.RemoveAddress(context.Background(), name, primaryIP)
if err == nil || !contains(err.Error(), "refusing to remove primary address") {
t.Errorf("RemoveAddress primary = %v, want refusal error", err)
}
assert.ErrorContains(t, err, "refusing to remove primary address")
// With the override enabled, removal succeeds.
c.allowPrimaryRemoval = true
if err = c.RemoveAddress(context.Background(), name, primaryIP); err != nil {
t.Errorf("RemoveAddress with allowPrimaryRemoval: %v", err)
}
}
func contains(s, substr string) bool {
return strings.Contains(s, substr)
assert.NoError(t, c.RemoveAddress(context.Background(), name, primaryIP), "RemoveAddress with allowPrimaryRemoval")
}
func TestLinuxConfigurator(t *testing.T) {
@ -222,9 +170,7 @@ func TestLinuxConfigurator(t *testing.T) {
// Connect to netlink.
h, err := netlink.NewHandle()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
defer h.Close()
// Setup test link.
@ -234,15 +180,11 @@ func TestLinuxConfigurator(t *testing.T) {
HardwareAddr: net.HardwareAddr{0x52, 0x54, 0x00, 0x8b, 0x0d, 0x93},
}})
err = h.LinkAdd(eth0Link)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Set test link up.
err = h.LinkSetUp(eth0Link)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Add test IP.
testIP1 := &net.IPNet{
@ -250,9 +192,7 @@ func TestLinuxConfigurator(t *testing.T) {
Mask: net.CIDRMask(24, 32),
}
err = h.AddrAdd(eth0Link, &netlink.Addr{IPNet: testIP1})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Add default route.
testGW1 := net.ParseIP("1.2.3.1")
@ -266,9 +206,7 @@ func TestLinuxConfigurator(t *testing.T) {
Gw: testGW1,
}
err = h.RouteAdd(defaultRoute)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup test link.
eth1Name := "test_enp2s0"
@ -277,15 +215,11 @@ func TestLinuxConfigurator(t *testing.T) {
HardwareAddr: net.HardwareAddr{0x52, 0x54, 0x00, 0x8b, 0xad, 0x93},
}}
err = h.LinkAdd(eth1Link)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Set test link up.
err = h.LinkSetUp(eth1Link)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Add test IP.
testIP2 := &net.IPNet{
@ -293,9 +227,7 @@ func TestLinuxConfigurator(t *testing.T) {
Mask: net.CIDRMask(64, 128),
}
err = h.AddrAdd(eth1Link, &netlink.Addr{IPNet: testIP2})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Add default route.
testGW2 := net.ParseIP("fe80::1")
@ -311,9 +243,7 @@ func TestLinuxConfigurator(t *testing.T) {
Priority: 200,
}
err = h.RouteAdd(ipv6Route)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup configurator with test URL to test server.
c := &linuxConfigurator{configOptions: &configOptions{}}
@ -324,218 +254,146 @@ func TestLinuxConfigurator(t *testing.T) {
// Setup test results path.
testDir, err := filepath.Abs("./tests/configurator_linux")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
configPath := filepath.Join(tmpDir, "50-cloud-init.yaml")
err = fileCopy(filepath.Join(testDir, "50-cloud-init.yaml"), configPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup ifupdown and parse test file.
ci, err := newCloudInitWith(configPath, filepath.Join(tmpDir, "nothing.json"), filepath.Join(tmpDir, "cloud.cfg.d"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
c.ifaceBackends = append(c.ifaceBackends, namedIfaceBackend{"cloud-init", ci})
// Get list of interfaces.
interfaces, err := c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test add addresses.
testIP3 := &net.IPNet{IP: net.ParseIP("1.2.3.5"), Mask: net.CIDRMask(24, 32)}
err = c.AddAddress(context.Background(), eth0Name, testIP3, nil)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
testIP4 := &net.IPNet{IP: net.ParseIP("fc00:5aa8:7160:d9eb:1:0:1:5"), Mask: net.CIDRMask(64, 128)}
err = c.AddAddress(context.Background(), eth1Name, testIP4, net.ParseIP("fc00:5aa8:7160:d9eb::"))
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test remove addresses.
err = c.RemoveAddress(context.Background(), eth0Name, testIP1)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
err = c.RemoveAddress(context.Background(), eth1Name, testIP2)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test rollback on failures.
c.testAddress = "test_fail"
err = c.AddAddress(context.Background(), eth0Name, testIP1, nil)
if err == nil || err.Error() != "aborted operation due to loss of internet" {
t.Errorf("Failed rollback test: %v", err)
}
assert.EqualError(t, err, "aborted operation due to loss of internet", "Failed rollback test")
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test remove gateway.
err = c.AddAddress(context.Background(), eth0Name, testIP3, make(net.IP, 4))
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 4)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test add gateway rollback.
err = c.AddAddress(context.Background(), eth0Name, testIP3, testGW1)
if err == nil || err.Error() != "aborted operation due to loss of internet" {
t.Errorf("Failed rollback test: %v", err)
}
assert.EqualError(t, err, "aborted operation due to loss of internet", "Failed rollback test")
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 4)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test remove gateway.
c.testAddress = "test_success"
err = c.AddAddress(context.Background(), eth0Name, testIP3, testGW1)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test removing route.
err = c.RemoveRoute(context.Background(), eth1Name, ipv6Dest, testGW2)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 5)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 4)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test add route.
ipv4Dest := &net.IPNet{
@ -544,25 +402,17 @@ func TestLinuxConfigurator(t *testing.T) {
}
testGW3 := net.ParseIP("1.2.3.254")
err = c.AddRoute(context.Background(), eth0Name, ipv4Dest, testGW3, 100)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Get list of interfaces.
interfaces, err = c.GetInterfaces(context.Background())
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 6)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 5)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
}

305
configurator_windows.go
View file

@ -3,10 +3,12 @@ package netconfig
import (
"bytes"
"context"
"errors"
"fmt"
"net"
"net/netip"
"os"
"strings"
"golang.org/x/sys/windows"
"golang.zx2c4.com/wireguard/windows/tunnel/winipcfg"
@ -21,17 +23,22 @@ type windowsConfigurator struct {
*configOptions
}
// Returns the windows network configurator. Behaviour is tuned with Option
// values such as WithTestAddress and WithConnectivityCheck; use SetLogger to
// replace the package-wide logger.
func NewConfigurator(opts ...Option) (configurator Configurator, err error) {
// Returns the windows network configurator. ctx is accepted to match the Linux
// constructor, whose backend detection queries the init system; nothing here
// needs it. Behaviour is tuned with Option values such as WithTestAddress and
// WithConnectivityCheck; use SetLogger to replace the package-wide logger.
//
// Unlike Linux, no backend is required: winipcfg writes an adapter's addresses
// and routes straight into the registry, so a change persists across a reboot
// without any configuration file behind it. cloud-init is registered when found
// so an image-provisioned host keeps its two sources of truth in step.
func NewConfigurator(ctx context.Context, opts ...Option) (Configurator, error) {
options := newConfigOptions(opts...)
c := new(windowsConfigurator)
c.configOptions = options
configurator = c
var ci *cloudInit
ci, err = newCloudInit(options.backupRetention)
ci, err := newCloudInit(options.backupRetention)
if err != nil {
logger.Println("error parsing cloud-init:", err)
}
@ -44,8 +51,28 @@ func NewConfigurator(opts ...Option) (configurator Configurator, err error) {
// Detection failures are logged above; they are not fatal to constructing
// the configurator, so do not propagate them to the caller.
err = nil
return
return c, nil
}
// ipAdapterDHCPState reports whether the adapter runs a DHCP client for each
// address family. Windows exposes the two very differently: DHCPv4 is an
// adapter flag, while there is no DHCPv6 flag at all — an adapter is running a
// DHCPv6 client exactly when one of its addresses says it was learned from one.
func ipAdapterDHCPState(ipAdapter *winipcfg.IPAdapterAddresses) (dhcp4, dhcp6 bool) {
dhcp4 = ipAdapter.Flags&winipcfg.IPAAFlagDhcpv4Enabled != 0
for unicast := ipAdapter.FirstUnicastAddress; unicast != nil; unicast = unicast.Next {
ip := unicast.Address.IP()
if ip == nil || ip.To4() != nil {
continue
}
// IP_ADAPTER_UNICAST_ADDRESS carries the raw Win32 enum, so compare
// against winipcfg's typed constant for it rather than a bare 3.
if unicast.PrefixOrigin == int32(winipcfg.PrefixOriginDHCP) {
dhcp6 = true
break
}
}
return dhcp4, dhcp6
}
// Get IP addresses from ip adapter.
@ -106,6 +133,32 @@ func ipAdapterAddresses(ipAdapter *winipcfg.IPAdapterAddresses) (addresses []*ne
return
}
// adapterIsPhysical reports whether an adapter is backed by hardware. The
// interface type cannot answer that on its own: Windows hands a Hyper-V virtual
// switch, a VPN client's tunnel, and a real NIC the same Ethernet type. The
// interface row's hardware flag does answer it, and the endpoint flag rules out
// the host's own side of a virtual switch, which claims hardware backing it does
// not have. Adapters whose row cannot be read fall back to the interface type.
func adapterIsPhysical(adapter *winipcfg.IPAdapterAddresses) bool {
row, err := adapter.LUID.Interface()
if err != nil {
return isPhysicalIfType(adapter.IfType)
}
if row.InterfaceAndOperStatusFlags&winipcfg.IAOSFEndPointInterface != 0 {
return false
}
return row.InterfaceAndOperStatusFlags&winipcfg.IAOSFHardwareInterface != 0
}
// isPhysicalIfType reports whether an interface type is one a physical NIC uses.
func isPhysicalIfType(ifType winipcfg.IfType) bool {
switch uint32(ifType) {
case windows.IF_TYPE_ETHERNET_CSMACD, windows.IF_TYPE_IEEE80211:
return true
}
return false
}
// Get list of interfaces and their configs.
func (c *windowsConfigurator) GetInterfaces(ctx context.Context) (interfaces []*Interface, err error) {
// Reference of zero IP addresses.
@ -137,6 +190,9 @@ func (c *windowsConfigurator) GetInterfaces(ctx context.Context) (interfaces []*
i.Name = ipAdapter.FriendlyName()
i.MAC = ipAdapter.PhysicalAddress()
i.Link = ipAdapter.LUID
i.Up = ipAdapter.OperStatus == winipcfg.IfOperStatusUp
i.Physical = adapterIsPhysical(ipAdapter)
i.DHCP4, i.DHCP6 = ipAdapterDHCPState(ipAdapter)
for _, addr := range ipAdapterAddresses(ipAdapter) {
if !addr.IP.IsLinkLocalUnicast() {
i.Addresses = append(i.Addresses, addr)
@ -1008,3 +1064,236 @@ func (c *windowsConfigurator) SetDNS(ctx context.Context, iface string, servers
applyLiveDNSWindows(ctx, iface, servers, searchDomains)
return nil
}
// runNetsh runs netsh and folds its output into any error. netsh reports its
// failures on stdout, not stderr, so without this a failed call surfaces as a
// bare "exit status 1" with the reason discarded.
func runNetsh(ctx context.Context, args ...string) error {
out, err := runCommand(ctx, "netsh", args...)
if err == nil {
return nil
}
if reason := strings.TrimSpace(strings.Join(out, " ")); reason != "" {
return fmt.Errorf("netsh %s: %w: %s", strings.Join(args, " "), err, reason)
}
return fmt.Errorf("netsh %s: %w", strings.Join(args, " "), err)
}
// The netsh argument builders below all use the named-parameter form rather than
// netsh's positional shorthand ("set address name=X static 1.2.3.4 255.255.255.0
// 1.2.3.1"), which is order-sensitive and reads as a puzzle.
// netshEnableDHCP4Args switches an adapter's IPv4 configuration to DHCP. This
// both records the choice and starts the DHCP client, discarding whatever
// static addresses the adapter held.
func netshEnableDHCP4Args(iface string) []string {
return []string{"interface", "ipv4", "set", "address", "name=" + iface, "source=dhcp"}
}
// netshDNSFromDHCP4Args makes the adapter take its resolvers from the lease.
// Switching the address source to DHCP does not do this: the DNS servers are a
// separate setting and a statically configured resolver survives the switch.
func netshDNSFromDHCP4Args(iface string) []string {
return []string{"interface", "ipv4", "set", "dnsservers", "name=" + iface, "source=dhcp"}
}
// netshSetStatic4Args replaces the adapter's IPv4 configuration with a single
// static address. There is no netsh verb for "stop being a DHCP client": an
// adapter leaves DHCP by being given a static address, so this is how DHCPv4 is
// turned off.
//
// A nil gateway is written as "none" rather than omitted. Omitting it leaves the
// previous default gateway in place, which on an adapter that has just stopped
// leasing means keeping a gateway the DHCP server handed out.
func netshSetStatic4Args(iface string, addr *net.IPNet, gateway net.IP) []string {
args := []string{
"interface", "ipv4", "set", "address",
"name=" + iface,
"source=static",
"address=" + addr.IP.String(),
"mask=" + net.IP(addr.Mask).String(),
}
if gateway != nil {
return append(args, "gateway="+gateway.String())
}
return append(args, "gateway=none")
}
// netshAddStatic4Args adds a secondary static IPv4 address. "set address"
// replaces the adapter's entire IPv4 configuration with the one address it is
// given, so every address after the first has to be re-added with this.
func netshAddStatic4Args(iface string, addr *net.IPNet) []string {
return []string{
"interface", "ipv4", "add", "address",
"name=" + iface,
"address=" + addr.IP.String(),
"mask=" + net.IP(addr.Mask).String(),
}
}
// netshSetDHCP6Args turns the DHCPv6 client on or off.
//
// IPv6 has no "source=dhcp" counterpart, because Windows does not model DHCPv6
// as an address source. A host runs a DHCPv6 client when a router advertisement
// tells it to, via the M (managed address) and O (other stateful config) bits;
// these two interface flags are the local override of those bits. Router
// discovery is enabled alongside them because DHCPv6 conveys no default route —
// only router advertisements do — so an interface leasing an address with
// router discovery off would have no way to reach anything.
//
// Disabling leaves router discovery alone: whatever default route the RA
// provides is not this call's to take away.
func netshSetDHCP6Args(iface string, enable bool) []string {
args := []string{"interface", "ipv6", "set", "interface", "interface=" + iface}
if enable {
return append(args, "routerdiscovery=enabled", "managedaddress=enabled", "otherstateful=enabled")
}
return append(args, "managedaddress=disabled", "otherstateful=disabled")
}
// ipconfigRenewArgs asks the DHCP client to acquire a lease now. Switching the
// address source to DHCP starts the client, but a renew makes the lease arrive
// before this call returns rather than at the client's own pace.
func ipconfigRenewArgs(iface string) []string {
return []string{"/renew", iface}
}
// requireElevation reports an error unless this process holds an elevated token.
// Every write path below reconfigures a live NIC and fails with a bare access
// denied otherwise; under UAC an account in the Administrators group still runs
// with a filtered standard-user token unless it was explicitly elevated. Saying
// so up front beats a netsh error the caller has to decode.
func requireElevation() error {
if windows.GetCurrentProcessToken().IsElevated() {
return nil
}
return fmt.Errorf("changing an adapter's DHCP configuration requires an elevated process")
}
// Enable or disable the DHCP client for each address family on an interface.
//
// Windows keeps no configuration file of its own, so unlike Linux the adapter is
// both the persisted configuration and the running system, and there is nothing
// to reconcile later: the netsh calls below record the choice and act on it at
// once. A file backend that is also present (cloudbase-init) is written first,
// so a re-provision does not undo what was just set.
//
// The two families are asymmetric. IPv4 has an address source that can be set to
// dhcp or static. IPv6 does not — DHCPv6 is driven by the router advertisement's
// M and O bits, which netshSetDHCP6Args overrides locally. Note that a DHCPv6
// lease carries no default route, so an interface's IPv6 reachability still
// depends on router advertisements either way.
func (c *windowsConfigurator) SetDHCP(ctx context.Context, iface string, dhcp4, dhcp6 bool) error {
// Check this before touching anything, so a non-elevated caller is told why
// rather than left with the file backends written and the adapter untouched.
if err := requireElevation(); err != nil {
return err
}
applyIfaceDHCP(ctx, c.ifaceBackends, iface, dhcp4, dhcp6)
var errs []error
if err := setAdapterDHCP4(ctx, iface, dhcp4); err != nil {
errs = append(errs, err)
}
if err := runNetsh(ctx, netshSetDHCP6Args(iface, dhcp6)...); err != nil {
errs = append(errs, fmt.Errorf("failed to set dhcp6 on %s: %w", iface, err))
}
return errors.Join(errs...)
}
// setAdapterDHCP4 switches the adapter's IPv4 address source.
func setAdapterDHCP4(ctx context.Context, iface string, enable bool) error {
if enable {
if err := runNetsh(ctx, netshEnableDHCP4Args(iface)...); err != nil {
return fmt.Errorf("failed to enable dhcp4 on %s: %w", iface, err)
}
// The resolvers are a separate setting that survives the address-source
// switch; a statically configured one would otherwise outlive the static
// address it was set alongside. Failing to hand DNS back to the lease
// leaves a working interface, so it is logged rather than returned.
if err := runNetsh(ctx, netshDNSFromDHCP4Args(iface)...); err != nil {
logger.Printf("SetDHCP: %s: enabled dhcp4 but failed to take DNS from the lease: %v", iface, err)
}
// Setting the source starts the DHCP client; renewing makes the lease
// arrive before this call returns. A renew that finds no DHCP server
// fails, which does not undo the configuration that was just written.
if _, err := runCommand(ctx, "ipconfig", ipconfigRenewArgs(iface)...); err != nil {
logger.Printf("SetDHCP: %s: enabled dhcp4 but no lease acquired yet: %v", iface, err)
}
return nil
}
// An adapter leaves DHCP by being given a static address. Re-assert the
// addresses it currently holds — which are the leased ones — so it keeps the
// address it is reachable on and simply stops renewing it.
adapter, err := findAdapter(iface)
if err != nil {
return err
}
// An adapter that is not leasing has nothing to convert. Running the static
// assignment on it anyway would tear its IPv4 configuration down and build
// it back up for no reason.
if dhcp4, _ := ipAdapterDHCPState(adapter); !dhcp4 {
return nil
}
addrs := ipv4AdapterAddresses(adapter)
if len(addrs) == 0 {
return fmt.Errorf("cannot disable dhcp4 on %s: it holds no IPv4 address to keep statically", iface)
}
// "set address" replaces the adapter's whole IPv4 configuration with the one
// address it is given, so the rest are re-added after it.
if err := runNetsh(ctx, netshSetStatic4Args(iface, addrs[0], ipAdapterGateway4(adapter))...); err != nil {
return fmt.Errorf("failed to disable dhcp4 on %s: %w", iface, err)
}
var errs []error
for _, addr := range addrs[1:] {
if err := runNetsh(ctx, netshAddStatic4Args(iface, addr)...); err != nil {
errs = append(errs, fmt.Errorf("failed to restore secondary address %s on %s: %w", addr, iface, err))
}
}
return errors.Join(errs...)
}
// findAdapter returns the adapter with the given friendly name, which is the
// name netsh and ipconfig also identify it by.
func findAdapter(iface string) (*winipcfg.IPAdapterAddresses, error) {
ipAdapters, err := winipcfg.GetAdaptersAddresses(windows.AF_UNSPEC, winipcfg.GAAFlagIncludePrefix|winipcfg.GAAFlagSkipAnycast|winipcfg.GAAFlagSkipMulticast|winipcfg.GAAFlagSkipDNSServer|winipcfg.GAAFlagSkipFriendlyName|winipcfg.GAAFlagSkipDNSInfo)
if err != nil {
return nil, err
}
for _, ipAdapter := range ipAdapters {
if ipAdapter.FriendlyName() == iface {
return ipAdapter, nil
}
}
return nil, fmt.Errorf("no adapter found with name: %s", iface)
}
// ipv4AdapterAddresses returns every non-link-local IPv4 address the adapter
// holds, in the order it holds them, which is what converting it from DHCP to
// static must re-assert.
func ipv4AdapterAddresses(adapter *winipcfg.IPAdapterAddresses) (addrs []*net.IPNet) {
for _, addr := range ipAdapterAddresses(adapter) {
if addr.IP.To4() == nil || addr.IP.IsLinkLocalUnicast() {
continue
}
addrs = append(addrs, addr)
}
return addrs
}
// ipAdapterGateway4 returns the adapter's first IPv4 default gateway, or nil.
func ipAdapterGateway4(ipAdapter *winipcfg.IPAdapterAddresses) net.IP {
for gw := ipAdapter.FirstGatewayAddress; gw != nil; gw = gw.Next {
if ip := gw.Address.IP(); ip != nil && ip.To4() != nil {
return ip
}
}
return nil
}

104
cpanel_test.go
View file

@ -4,6 +4,9 @@ import (
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// parseJSON unmarshals a single line of whmapi1 output; verify its guard on
@ -14,33 +17,24 @@ func TestCpanelParseJSON(t *testing.T) {
t.Run("valid single line", func(t *testing.T) {
var v cpanelBase
err := c.parseJSON([]string{`{"metadata":{"command":"listips","result":1}}`}, &v)
if err != nil {
t.Fatalf("unexpected error: %v", err)
}
if v.Metadata.Command != "listips" || v.Metadata.Result != 1 {
t.Errorf("decoded = %+v, want command=listips result=1", v.Metadata)
}
require.NoError(t, err)
assert.Equal(t, "listips", v.Metadata.Command)
assert.Equal(t, 1, v.Metadata.Result)
})
t.Run("no output errors", func(t *testing.T) {
var v cpanelBase
if err := c.parseJSON(nil, &v); err == nil {
t.Error("expected error for empty output")
}
assert.Error(t, c.parseJSON(nil, &v))
})
t.Run("multiple lines errors", func(t *testing.T) {
var v cpanelBase
if err := c.parseJSON([]string{"{}", "{}"}, &v); err == nil {
t.Error("expected error for multi-line output")
}
assert.Error(t, c.parseJSON([]string{"{}", "{}"}, &v))
})
t.Run("invalid json errors", func(t *testing.T) {
var v cpanelBase
if err := c.parseJSON([]string{"not json"}, &v); err == nil {
t.Error("expected error for invalid json")
}
assert.Error(t, c.parseJSON([]string{"not json"}, &v))
})
}
@ -51,93 +45,53 @@ func TestSetWWWAcctAddr(t *testing.T) {
t.Run("replaces existing ADDR and preserves other lines", func(t *testing.T) {
path := filepath.Join(t.TempDir(), "wwwacct.conf")
content := "HOST server.example.com\nADDR 203.0.113.10\nNS ns1.example.com\n"
if err := os.WriteFile(path, []byte(content), 0644); err != nil {
t.Fatal(err)
}
if err := setWWWAcctAddr(path, "ADDR", "203.0.113.20"); err != nil {
t.Fatalf("setWWWAcctAddr: %v", err)
}
require.NoError(t, os.WriteFile(path, []byte(content), 0644))
require.NoError(t, setWWWAcctAddr(path, "ADDR", "203.0.113.20"))
got, err := os.ReadFile(path)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
want := "HOST server.example.com\nADDR 203.0.113.20\nNS ns1.example.com\n"
if string(got) != want {
t.Errorf("got:\n%s\nwant:\n%s", got, want)
}
assert.Equal(t, want, string(got))
})
t.Run("appends ADDR when absent", func(t *testing.T) {
path := filepath.Join(t.TempDir(), "wwwacct.conf")
if err := os.WriteFile(path, []byte("HOST server.example.com\n"), 0644); err != nil {
t.Fatal(err)
}
if err := setWWWAcctAddr(path, "ADDR", "203.0.113.20"); err != nil {
t.Fatalf("setWWWAcctAddr: %v", err)
}
require.NoError(t, os.WriteFile(path, []byte("HOST server.example.com\n"), 0644))
require.NoError(t, setWWWAcctAddr(path, "ADDR", "203.0.113.20"))
got, err := os.ReadFile(path)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
want := "HOST server.example.com\nADDR 203.0.113.20\n"
if string(got) != want {
t.Errorf("got:\n%q\nwant:\n%q", got, want)
}
assert.Equal(t, want, string(got))
})
t.Run("setting ADDR does not touch ADDR6", func(t *testing.T) {
path := filepath.Join(t.TempDir(), "wwwacct.conf")
content := "ADDR 203.0.113.10\nADDR6 2001:db8::1\n"
if err := os.WriteFile(path, []byte(content), 0644); err != nil {
t.Fatal(err)
}
if err := setWWWAcctAddr(path, "ADDR", "203.0.113.20"); err != nil {
t.Fatalf("setWWWAcctAddr: %v", err)
}
require.NoError(t, os.WriteFile(path, []byte(content), 0644))
require.NoError(t, setWWWAcctAddr(path, "ADDR", "203.0.113.20"))
got, err := os.ReadFile(path)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
want := "ADDR 203.0.113.20\nADDR6 2001:db8::1\n"
if string(got) != want {
t.Errorf("got:\n%s\nwant:\n%s", got, want)
}
assert.Equal(t, want, string(got))
})
t.Run("setting ADDR6 replaces it and leaves ADDR alone", func(t *testing.T) {
path := filepath.Join(t.TempDir(), "wwwacct.conf")
content := "ADDR 203.0.113.10\nADDR6 2001:db8::1\n"
if err := os.WriteFile(path, []byte(content), 0644); err != nil {
t.Fatal(err)
}
if err := setWWWAcctAddr(path, "ADDR6", "2001:db8::20"); err != nil {
t.Fatalf("setWWWAcctAddr: %v", err)
}
require.NoError(t, os.WriteFile(path, []byte(content), 0644))
require.NoError(t, setWWWAcctAddr(path, "ADDR6", "2001:db8::20"))
got, err := os.ReadFile(path)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
want := "ADDR 203.0.113.10\nADDR6 2001:db8::20\n"
if string(got) != want {
t.Errorf("got:\n%s\nwant:\n%s", got, want)
}
assert.Equal(t, want, string(got))
})
t.Run("appends ADDR6 when absent", func(t *testing.T) {
path := filepath.Join(t.TempDir(), "wwwacct.conf")
if err := os.WriteFile(path, []byte("ADDR 203.0.113.10\n"), 0644); err != nil {
t.Fatal(err)
}
if err := setWWWAcctAddr(path, "ADDR6", "2001:db8::20"); err != nil {
t.Fatalf("setWWWAcctAddr: %v", err)
}
require.NoError(t, os.WriteFile(path, []byte("ADDR 203.0.113.10\n"), 0644))
require.NoError(t, setWWWAcctAddr(path, "ADDR6", "2001:db8::20"))
got, err := os.ReadFile(path)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
want := "ADDR 203.0.113.10\nADDR6 2001:db8::20\n"
if string(got) != want {
t.Errorf("got:\n%s\nwant:\n%s", got, want)
}
assert.Equal(t, want, string(got))
})
}

659
dhcp_unit_test.go Normal file
View file

@ -0,0 +1,659 @@
package netconfig
import (
"context"
"net"
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"gopkg.in/ini.v1"
)
// cidr is a terse *net.IPNet literal for the tests below.
func cidr(t *testing.T, s string) *net.IPNet {
t.Helper()
ip, ipnet, err := net.ParseCIDR(s)
require.NoError(t, err)
ipnet.IP = ip
return ipnet
}
// A netplan interface must report and record each family's client
// independently, and must not grow a dhcp4/dhcp6 key that was never there.
func TestNetplanSetDHCP(t *testing.T) {
t.Run("reads absent keys as off", func(t *testing.T) {
dhcp4, dhcp6 := (&npInterface{}).dhcpState()
assert.False(t, dhcp4)
assert.False(t, dhcp6)
})
t.Run("enables one family without touching the other", func(t *testing.T) {
c := npInterface{}
c.setDHCP(true, false)
require.NotNil(t, c.DHCP4)
assert.True(t, *c.DHCP4)
assert.Nil(t, c.DHCP6, "dhcp6 was absent and stays absent when disabled")
})
t.Run("disabling drops that family's overrides only", func(t *testing.T) {
c := npInterface{
DHCP4: boolPtr(true),
DHCP6: boolPtr(true),
DHCP4Overrides: map[string]any{"use-dns": false},
DHCP6Overrides: map[string]any{"use-dns": false},
}
c.setDHCP(false, true)
assert.False(t, *c.DHCP4)
assert.Nil(t, c.DHCP4Overrides, "overrides of a stopped client are dead config")
assert.True(t, *c.DHCP6)
assert.NotNil(t, c.DHCP6Overrides)
})
t.Run("disabling an absent key does not write it", func(t *testing.T) {
c := npInterface{}
c.setDHCP(false, false)
assert.Nil(t, c.DHCP4)
assert.Nil(t, c.DHCP6)
})
t.Run("round trips through dhcpState", func(t *testing.T) {
c := npInterface{}
c.setDHCP(true, true)
dhcp4, dhcp6 := c.dhcpState()
assert.True(t, dhcp4)
assert.True(t, dhcp6)
})
}
func TestCloudInitSetDHCP(t *testing.T) {
c := ciInterface{DHCP4: boolPtr(true), DHCP6Overrides: map[string]any{"use-dns": false}}
c.setDHCP(false, false)
require.NotNil(t, c.DHCP4)
assert.False(t, *c.DHCP4)
assert.Nil(t, c.DHCP6, "absent stays absent")
assert.Nil(t, c.DHCP6Overrides)
}
func TestParseNetworkdDHCP(t *testing.T) {
tests := []struct {
value string
dhcp4, dhcp6 bool
}{
{value: "yes", dhcp4: true, dhcp6: true},
{value: "true", dhcp4: true, dhcp6: true},
{value: "both", dhcp4: true, dhcp6: true},
{value: " YES ", dhcp4: true, dhcp6: true},
{value: "ipv4", dhcp4: true},
{value: "v4", dhcp4: true},
{value: "ipv6", dhcp6: true},
{value: "no"},
{value: "none"},
{value: ""},
{value: "garbage"},
}
for _, tt := range tests {
t.Run(tt.value, func(t *testing.T) {
dhcp4, dhcp6 := parseNetworkdDHCP(tt.value)
assert.Equal(t, tt.dhcp4, dhcp4, "dhcp4")
assert.Equal(t, tt.dhcp6, dhcp6, "dhcp6")
})
}
}
func TestFormatNetworkdDHCP(t *testing.T) {
tests := []struct {
name string
dhcp4, dhcp6 bool
value string
keep bool
}{
{name: "both", dhcp4: true, dhcp6: true, value: "yes", keep: true},
{name: "v4", dhcp4: true, value: "ipv4", keep: true},
{name: "v6", dhcp6: true, value: "ipv6", keep: true},
{name: "neither", value: "", keep: false},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
value, keep := formatNetworkdDHCP(tt.dhcp4, tt.dhcp6)
assert.Equal(t, tt.keep, keep)
assert.Equal(t, tt.value, value)
})
}
}
// networkdDHCPValue builds a [Network] section carrying the given DHCP= value
// ("" for no key at all), runs setNetworkdDHCP over it, and reports the
// resulting value plus whether the key survived.
func networkdDHCPValue(t *testing.T, start string, dhcp4, dhcp6 bool) (string, bool) {
t.Helper()
cfg := ini.Empty()
sec, err := cfg.NewSection("Network")
require.NoError(t, err)
if start != "" {
_, err = sec.NewKey("DHCP", start)
require.NoError(t, err)
}
require.NoError(t, setNetworkdDHCP(sec, dhcp4, dhcp6))
if !sec.HasKey("DHCP") {
return "", false
}
return sec.Key("DHCP").String(), true
}
func TestSetNetworkdDHCP(t *testing.T) {
t.Run("narrows a dual-stack lease to one family", func(t *testing.T) {
value, present := networkdDHCPValue(t, "yes", false, true)
require.True(t, present)
assert.Equal(t, "ipv6", value)
})
t.Run("removes the key when no family is left", func(t *testing.T) {
_, present := networkdDHCPValue(t, "ipv4", false, false)
assert.False(t, present, "DHCP= should be removed, not written as no")
})
t.Run("creates the key on a config that lacked it", func(t *testing.T) {
value, present := networkdDHCPValue(t, "", true, false)
require.True(t, present)
assert.Equal(t, "ipv4", value)
})
t.Run("leaves an absent key absent when disabling", func(t *testing.T) {
_, present := networkdDHCPValue(t, "", false, false)
assert.False(t, present)
})
}
// A .network file must round trip through SetIfaceDHCP and GetInterfaces, and
// SetIfaceAddresses must not disturb the DHCP key on the way past.
func TestNetworkdSetIfaceDHCP(t *testing.T) {
newNetworkdDir := func(t *testing.T, body string) (string, string) {
t.Helper()
dir := t.TempDir()
path := filepath.Join(dir, "eth0.network")
require.NoError(t, os.WriteFile(path, []byte(body), 0644))
return dir, path
}
t.Run("enables a family and reads it back", func(t *testing.T) {
dir, path := newNetworkdDir(t, "[Match]\nName=eth0\n\n[Network]\nAddress=1.2.3.4/24\n")
nd, err := readNetworkdConfigDirectory(dir)
require.NoError(t, err)
require.NoError(t, nd.SetIfaceDHCP(context.Background(), "eth0", true, false))
cfg, err := ini.Load(path)
require.NoError(t, err)
assert.Equal(t, "ipv4", cfg.Section("Network").Key("DHCP").String())
assert.Equal(t, "1.2.3.4/24", cfg.Section("Network").Key("Address").String(),
"the static address must survive enabling DHCP")
})
t.Run("a DHCP-only network still reports its state", func(t *testing.T) {
dir, _ := newNetworkdDir(t, "[Match]\nName=eth0\n\n[Network]\nDHCP=yes\n")
nd, err := readNetworkdConfigDirectory(dir)
require.NoError(t, err)
ifaces, err := nd.GetInterfaces()
require.NoError(t, err)
require.Len(t, ifaces, 1)
assert.True(t, ifaces[0].DHCP4, "a network with no Address must still report DHCP")
assert.True(t, ifaces[0].DHCP6)
})
t.Run("setting addresses leaves DHCP alone", func(t *testing.T) {
dir, path := newNetworkdDir(t, "[Match]\nName=eth0\n\n[Network]\nDHCP=yes\n")
nd, err := readNetworkdConfigDirectory(dir)
require.NoError(t, err)
err = nd.SetIfaceAddresses(context.Background(), "eth0",
[]*net.IPNet{cidr(t, "1.2.3.4/24")}, net.ParseIP("1.2.3.1"), nil)
require.NoError(t, err)
cfg, err := ini.Load(path)
require.NoError(t, err)
assert.Equal(t, "yes", cfg.Section("Network").Key("DHCP").String(),
"adding a static address must not disable DHCP")
assert.Equal(t, "1.2.3.4/24", cfg.Section("Network").Key("Address").String())
})
}
func TestNSDHCPState(t *testing.T) {
tests := []struct {
name string
config map[string]string
dhcp4, dhcp6 bool
}{
{name: "empty", config: map[string]string{}},
{name: "static", config: map[string]string{"BOOTPROTO": "none"}},
{name: "dhcp", config: map[string]string{"BOOTPROTO": "dhcp"}, dhcp4: true},
{name: "uppercase dhcp", config: map[string]string{"BOOTPROTO": "DHCP"}, dhcp4: true},
{name: "bootp is dynamic", config: map[string]string{"BOOTPROTO": "bootp"}, dhcp4: true},
{name: "dhcpv6c", config: map[string]string{"DHCPV6C": "yes"}, dhcp6: true},
{
name: "both",
config: map[string]string{"BOOTPROTO": "dhcp", "DHCPV6C": "yes"},
dhcp4: true, dhcp6: true,
},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
dhcp4, dhcp6 := nsDHCPState(tt.config)
assert.Equal(t, tt.dhcp4, dhcp4, "dhcp4")
assert.Equal(t, tt.dhcp6, dhcp6, "dhcp6")
})
}
}
func TestNetworkScriptsSetIfaceDHCP(t *testing.T) {
// Re-read the ifcfg file from disk so we assert on what was persisted.
readConfig := func(t *testing.T, dir string) map[string]string {
t.Helper()
ns, err := newNetworkScriptsWithConfig(dir)
require.NoError(t, err)
require.Len(t, ns.Interfaces, 1)
require.Len(t, ns.Interfaces[0].IFFiles, 1)
return ns.Interfaces[0].IFFiles[0].Config
}
newDir := func(t *testing.T, body string) string {
t.Helper()
dir := t.TempDir()
require.NoError(t, os.WriteFile(filepath.Join(dir, "ifcfg-eth0"), []byte(body), 0644))
return dir
}
t.Run("enabling ipv4 keeps the static address", func(t *testing.T) {
dir := newDir(t, "DEVICE=eth0\nBOOTPROTO=none\nIPADDR0=1.2.3.4\nPREFIX0=24\n")
ns, err := newNetworkScriptsWithConfig(dir)
require.NoError(t, err)
require.NoError(t, ns.SetIfaceDHCP(context.Background(), "eth0", true, false))
config := readConfig(t, dir)
assert.Equal(t, "dhcp", config["BOOTPROTO"])
assert.Equal(t, "1.2.3.4", config["IPADDR0"], "the static address must survive")
})
t.Run("disabling ipv4 writes none and drops the dhclient option", func(t *testing.T) {
dir := newDir(t, "DEVICE=eth0\nBOOTPROTO=dhcp\nPERSISTENT_DHCLIENT=1\n")
ns, err := newNetworkScriptsWithConfig(dir)
require.NoError(t, err)
require.NoError(t, ns.SetIfaceDHCP(context.Background(), "eth0", false, false))
config := readConfig(t, dir)
assert.Equal(t, "none", config["BOOTPROTO"])
_, ok := config["PERSISTENT_DHCLIENT"]
assert.False(t, ok)
})
t.Run("the two families are independent", func(t *testing.T) {
dir := newDir(t, "DEVICE=eth0\nBOOTPROTO=dhcp\nDHCPV6C=yes\n")
ns, err := newNetworkScriptsWithConfig(dir)
require.NoError(t, err)
require.NoError(t, ns.SetIfaceDHCP(context.Background(), "eth0", false, true))
config := readConfig(t, dir)
assert.Equal(t, "none", config["BOOTPROTO"])
assert.Equal(t, "yes", config["DHCPV6C"])
assert.Equal(t, "yes", config["IPV6INIT"], "DHCPv6 needs IPv6 turned on")
})
t.Run("adding an address leaves BOOTPROTO alone", func(t *testing.T) {
dir := newDir(t, "DEVICE=eth0\nBOOTPROTO=dhcp\n")
ns, err := newNetworkScriptsWithConfig(dir)
require.NoError(t, err)
err = ns.SetIfaceAddresses(context.Background(), "eth0",
[]*net.IPNet{cidr(t, "1.2.3.4/24")}, nil, nil)
require.NoError(t, err)
config := readConfig(t, dir)
assert.Equal(t, "dhcp", config["BOOTPROTO"],
"a static address may coexist with a lease; only SetDHCP turns it off")
assert.Equal(t, "1.2.3.4", config["IPADDR0"])
})
t.Run("reads the state back through GetInterfaces", func(t *testing.T) {
dir := newDir(t, "DEVICE=eth0\nBOOTPROTO=dhcp\nDHCPV6C=yes\n")
ns, err := newNetworkScriptsWithConfig(dir)
require.NoError(t, err)
ifaces, err := ns.GetInterfaces()
require.NoError(t, err)
require.Len(t, ifaces, 1)
assert.True(t, ifaces[0].DHCP4)
assert.True(t, ifaces[0].DHCP6)
})
}
func TestIfUpDownSetDHCP(t *testing.T) {
t.Run("converts the stanza method for its own family", func(t *testing.T) {
iface := &ifInterface{Name: "eth0", Mode: "inet static"}
require.NoError(t, iface.setDHCP(true, false))
assert.Equal(t, "inet dhcp", iface.Mode)
assert.True(t, iface.isDHCP)
require.NoError(t, iface.setDHCP(false, false))
assert.Equal(t, "inet static", iface.Mode)
assert.False(t, iface.isDHCP)
})
t.Run("inet6 stanza follows dhcp6", func(t *testing.T) {
iface := &ifInterface{Name: "eth0", Mode: "inet6 static"}
require.NoError(t, iface.setDHCP(false, true))
assert.Equal(t, "inet6 dhcp", iface.Mode)
assert.True(t, iface.isDHCP)
})
t.Run("a stanza-less interface gets one", func(t *testing.T) {
iface := &ifInterface{Name: "eth0"}
require.NoError(t, iface.setDHCP(true, false))
assert.Equal(t, "inet dhcp", iface.Mode)
})
t.Run("errors rather than silently ignoring the other family", func(t *testing.T) {
iface := &ifInterface{Name: "eth0", Mode: "inet static"}
err := iface.setDHCP(false, true)
assert.ErrorContains(t, err, "other family")
assert.Equal(t, "inet static", iface.Mode, "the stanza must be untouched on error")
})
t.Run("errors on both families at once", func(t *testing.T) {
iface := &ifInterface{Name: "eth0"}
assert.ErrorContains(t, iface.setDHCP(true, true), "both families")
})
t.Run("refuses methods it cannot convert", func(t *testing.T) {
for _, method := range []string{"loopback", "ppp"} {
iface := &ifInterface{Name: "lo", Mode: "inet " + method}
assert.ErrorContains(t, iface.setDHCP(true, false), method)
}
})
t.Run("dhcpState reports the stanza's family only", func(t *testing.T) {
dhcp4, dhcp6 := (&ifInterface{Mode: "inet dhcp", isDHCP: true}).dhcpState()
assert.True(t, dhcp4)
assert.False(t, dhcp6)
dhcp4, dhcp6 = (&ifInterface{Mode: "inet6 dhcp", isDHCP: true}).dhcpState()
assert.False(t, dhcp4)
assert.True(t, dhcp6)
dhcp4, dhcp6 = (&ifInterface{Mode: "inet static"}).dhcpState()
assert.False(t, dhcp4)
assert.False(t, dhcp6)
})
}
// Switching an ifupdown interface to DHCP must drop the static addressing the
// stanza carried, since a "dhcp" stanza has no address option to hold it.
func TestIfUpDownSetIfaceDHCPPersists(t *testing.T) {
dir := t.TempDir()
cfgPath := filepath.Join(dir, "interfaces")
config := "auto eth0\niface eth0 inet static\n\taddress 1.2.3.4/24\n\tgateway 1.2.3.1\n"
require.NoError(t, os.WriteFile(cfgPath, []byte(config), 0644))
i := &ifUpDown{BaseConfig: cfgPath, BackupDir: filepath.Join(dir, "backup")}
require.NoError(t, os.Mkdir(i.BackupDir, 0755))
require.NoError(t, i.ReadFile(cfgPath))
require.NoError(t, i.SetIfaceDHCP(context.Background(), "eth0", true, false))
// Re-read from disk to confirm what was persisted.
reread := &ifUpDown{BaseConfig: cfgPath, BackupDir: i.BackupDir}
require.NoError(t, reread.ReadFile(cfgPath))
require.Len(t, reread.Interfaces, 1)
eth0 := reread.Interfaces[0]
assert.Equal(t, "inet dhcp", eth0.Mode)
assert.True(t, eth0.isDHCP)
assert.Empty(t, eth0.Addresses, "a dhcp stanza cannot carry a static address")
assert.Nil(t, eth0.Gateway4)
// And the interface reports itself as DHCPv4.
ifaces, err := reread.GetInterfaces()
require.NoError(t, err)
require.Len(t, ifaces, 1)
assert.True(t, ifaces[0].DHCP4)
assert.False(t, ifaces[0].DHCP6)
}
// SetIfaceAddresses must leave netplan's dhcp4 alone: a static address and a
// lease coexist, and only SetIfaceDHCP decides otherwise.
func TestNetplanSetIfaceAddressesKeepsDHCP(t *testing.T) {
dir := t.TempDir()
path := filepath.Join(dir, "01-netcfg.yaml")
config := "network:\n version: 2\n ethernets:\n eth0:\n dhcp4: true\n"
require.NoError(t, os.WriteFile(path, []byte(config), 0644))
np, err := readNetplanConfigDirectory(dir)
require.NoError(t, err)
err = np.SetIfaceAddresses(context.Background(), "eth0",
[]*net.IPNet{cidr(t, "1.2.3.4/24")}, net.ParseIP("1.2.3.1"), nil)
require.NoError(t, err)
reread, err := readNetplanConfigDirectory(dir)
require.NoError(t, err)
require.Len(t, reread.configs, 1)
eth0, ok := reread.configs[0].Network.Ethernets["eth0"]
require.True(t, ok)
require.NotNil(t, eth0.DHCP4)
assert.True(t, *eth0.DHCP4, "adding a static address must not disable DHCP")
assert.Equal(t, []string{"1.2.3.4/24"}, eth0.Addresses)
}
// SetIfaceDHCP must write netplan's dhcp4/dhcp6 and leave the addresses alone.
func TestNetplanSetIfaceDHCPPersists(t *testing.T) {
dir := t.TempDir()
path := filepath.Join(dir, "01-netcfg.yaml")
config := "network:\n version: 2\n ethernets:\n eth0:\n addresses:\n - 1.2.3.4/24\n"
require.NoError(t, os.WriteFile(path, []byte(config), 0644))
np, err := readNetplanConfigDirectory(dir)
require.NoError(t, err)
require.NoError(t, np.SetIfaceDHCP(context.Background(), "eth0", true, false))
reread, err := readNetplanConfigDirectory(dir)
require.NoError(t, err)
eth0, ok := reread.configs[0].Network.Ethernets["eth0"]
require.True(t, ok)
require.NotNil(t, eth0.DHCP4)
assert.True(t, *eth0.DHCP4)
assert.Nil(t, eth0.DHCP6, "the untouched family must not gain a key")
assert.Equal(t, []string{"1.2.3.4/24"}, eth0.Addresses,
"static addresses coexist with a lease")
// And it reads back through GetInterfaces.
ifaces, err := reread.GetInterfaces()
require.NoError(t, err)
require.Len(t, ifaces, 1)
assert.True(t, ifaces[0].DHCP4)
assert.False(t, ifaces[0].DHCP6)
}
// newTestCloudInit builds a cloudInit over a temporary network config file, so
// SetIfaceDHCP has somewhere real to Save to.
func newTestCloudInit(t *testing.T, config string) *cloudInit {
t.Helper()
dir := t.TempDir()
configPath := filepath.Join(dir, "network.yaml")
require.NoError(t, os.WriteFile(configPath, []byte(config), 0644))
ci, err := newCloudInitWith(configPath, filepath.Join(dir, "nothing.json"), filepath.Join(dir, "cloud.cfg.d"))
require.NoError(t, err)
return ci
}
// cloud-init's v1 schema encodes DHCP as a subnet type. Enabling a client must
// add that subnet without disturbing the static subnet beside it.
func TestCloudInitSetIfaceDHCPV1(t *testing.T) {
ci := newTestCloudInit(t, `network:
version: 1
config:
- type: physical
name: eth0
subnets:
- type: dhcp
- type: static
address: 1.2.3.4/24
gateway: 1.2.3.1
`)
// Turning IPv4 off and IPv6 on must replace the dhcp subnet with a dhcp6
// one and leave the static subnet in place.
require.NoError(t, ci.SetIfaceDHCP(context.Background(), "eth0", false, true))
subnets := ci.Network.Configs[0].Subnets
require.Len(t, subnets, 2)
assert.Equal(t, "dhcp6", subnets[0].Type)
assert.Equal(t, "static", subnets[1].Type)
assert.Equal(t, "1.2.3.4/24", subnets[1].Address)
ifaces, err := ci.GetInterfaces()
require.NoError(t, err)
require.Len(t, ifaces, 1)
assert.False(t, ifaces[0].DHCP4)
assert.True(t, ifaces[0].DHCP6)
}
// The v1 reader must recognise every spelling of a DHCP subnet.
func TestCloudInitV1DHCPSubnetTypes(t *testing.T) {
for _, tt := range []struct {
subnetType string
dhcp4, dhcp6 bool
}{
{subnetType: "dhcp", dhcp4: true},
{subnetType: "dhcp4", dhcp4: true},
{subnetType: "dhcp6", dhcp6: true},
{subnetType: "ipv6_dhcpv6-stateful", dhcp6: true},
{subnetType: "static"},
} {
t.Run(tt.subnetType, func(t *testing.T) {
ci := newTestCloudInit(t, `network:
version: 1
config:
- type: physical
name: eth0
subnets:
- type: `+tt.subnetType+`
address: 1.2.3.4/24
`)
ifaces, err := ci.GetInterfaces()
require.NoError(t, err)
require.Len(t, ifaces, 1)
assert.Equal(t, tt.dhcp4, ifaces[0].DHCP4, "dhcp4")
assert.Equal(t, tt.dhcp6, ifaces[0].DHCP6, "dhcp6")
})
}
}
// The v2 schema keeps DHCP in dhcp4/dhcp6 keys beside the static addresses.
func TestCloudInitSetIfaceDHCPV2(t *testing.T) {
ci := newTestCloudInit(t, `network:
version: 2
ethernets:
eth0:
addresses:
- 1.2.3.4/24
`)
require.NoError(t, ci.SetIfaceDHCP(context.Background(), "eth0", true, false))
eth0, ok := ci.Network.Ethernets["eth0"]
require.True(t, ok)
require.NotNil(t, eth0.DHCP4)
assert.True(t, *eth0.DHCP4)
assert.Nil(t, eth0.DHCP6, "the untouched family must not gain a key")
assert.Equal(t, []string{"1.2.3.4/24"}, eth0.Addresses)
}
func TestNMConnectionDHCPState(t *testing.T) {
tests := []struct {
name string
method4, method6 string
dhcp4, dhcp6 bool
}{
{name: "auto is dhcp", method4: "auto", method6: "auto", dhcp4: true, dhcp6: true},
{name: "manual is static", method4: "manual", method6: "manual"},
{name: "ipv6 dhcp method", method4: "manual", method6: "dhcp", dhcp6: true},
{name: "disabled", method4: "disabled", method6: "link-local"},
}
for _, tt := range tests {
t.Run(tt.name, func(t *testing.T) {
conn := &nmConnection{Method4: tt.method4, Method6: tt.method6}
dhcp4, dhcp6 := conn.dhcpState()
assert.Equal(t, tt.dhcp4, dhcp4, "dhcp4")
assert.Equal(t, tt.dhcp6, dhcp6, "dhcp6")
})
}
}
// Turning a lease off must leave behind a method that still serves whatever
// static addresses the connection holds, and not strand IPv6 with no address.
func TestNMStaticMethod(t *testing.T) {
assert.Equal(t, "manual", nmStaticMethod4(true))
assert.Equal(t, "disabled", nmStaticMethod4(false))
assert.Equal(t, "manual", nmStaticMethod6(true))
assert.Equal(t, "link-local", nmStaticMethod6(false))
}
// applyIfaceDHCP reports whether any backend persisted the change, which is what
// SetDHCP relies on before asking the running system for a lease.
func TestApplyIfaceDHCP(t *testing.T) {
t.Run("reports true when one backend succeeds", func(t *testing.T) {
failing := &fakeIfaceBackend{err: assert.AnError}
ok := &fakeIfaceBackend{}
applied := applyIfaceDHCP(context.Background(), []namedIfaceBackend{
{name: "broken", backend: failing},
{name: "good", backend: ok},
}, "eth0", true, false)
assert.True(t, applied)
assert.Equal(t, 1, failing.dhcpCalls, "a failing backend must not stop the others")
assert.Equal(t, 1, ok.dhcpCalls)
assert.True(t, ok.lastDHCP4)
assert.False(t, ok.lastDHCP6)
})
t.Run("reports false when every backend fails", func(t *testing.T) {
applied := applyIfaceDHCP(context.Background(), []namedIfaceBackend{
{name: "broken", backend: &fakeIfaceBackend{err: assert.AnError}},
}, "eth0", true, true)
assert.False(t, applied)
})
t.Run("reports false with no backends at all", func(t *testing.T) {
assert.False(t, applyIfaceDHCP(context.Background(), nil, "eth0", true, true))
})
}
// renewDHCPOnBackends must skip backends that cannot reconfigure the running
// system (cloud-init) rather than erroring on them.
func TestRenewDHCPOnBackends(t *testing.T) {
renewer := &fakeRenewerBackend{}
backends := []namedIfaceBackend{
{name: "cloud-init", backend: &fakeIfaceBackend{}}, // no renewDHCP method
{name: "netplan", backend: renewer},
}
renewDHCPOnBackends(context.Background(), backends, "eth0")
assert.Equal(t, 1, renewer.renewCalls)
assert.Equal(t, "eth0", renewer.lastIface)
}
// fakeRenewerBackend is a file backend that can also reconfigure the running
// system, satisfying both ifaceBackend and dhcpRenewer.
type fakeRenewerBackend struct {
fakeIfaceBackend
renewCalls int
lastIface string
renewErr error
}
func (f *fakeRenewerBackend) renewDHCP(_ context.Context, iface string) error {
f.renewCalls++
f.lastIface = iface
return f.renewErr
}

74
dns_backends_test.go
View file

@ -6,6 +6,9 @@ import (
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// readIfcfg parses a written ifcfg-<iface> file back into a key/value map so
@ -13,9 +16,7 @@ import (
func readIfcfg(t *testing.T, dir, iface string) map[string]string {
t.Helper()
data, err := os.ReadFile(filepath.Join(dir, "ifcfg-"+iface))
if err != nil {
t.Fatalf("read ifcfg-%s: %v", iface, err)
}
require.NoError(t, err)
out := make(map[string]string)
for _, line := range splitLines(string(data)) {
k, v, ok := cutKV(line)
@ -68,32 +69,21 @@ func TestNetworkScriptsDNSPeerDNS(t *testing.T) {
err := ns.SetIfaceDNS(context.Background(), "eth0",
[]net.IP{net.ParseIP("1.1.1.1"), net.ParseIP("8.8.8.8")},
[]string{"example.com"})
if err != nil {
t.Fatalf("SetIfaceDNS: %v", err)
}
require.NoError(t, err)
cfg := readIfcfg(t, dir, "eth0")
if cfg["PEERDNS"] != "no" {
t.Errorf("PEERDNS = %q, want \"no\"", cfg["PEERDNS"])
}
if cfg["DNS1"] != "1.1.1.1" || cfg["DNS2"] != "8.8.8.8" {
t.Errorf("DNS1/DNS2 = %q/%q, want 1.1.1.1/8.8.8.8", cfg["DNS1"], cfg["DNS2"])
}
if cfg["DOMAIN"] != "example.com" {
t.Errorf("DOMAIN = %q, want example.com", cfg["DOMAIN"])
}
assert.Equal(t, "no", cfg["PEERDNS"])
assert.Equal(t, "1.1.1.1", cfg["DNS1"])
assert.Equal(t, "8.8.8.8", cfg["DNS2"])
assert.Equal(t, "example.com", cfg["DOMAIN"])
// Clearing DNS should drop PEERDNS so DHCP-provided resolvers resume.
err = ns.SetIfaceDNS(context.Background(), "eth0", nil, nil)
if err != nil {
t.Fatalf("SetIfaceDNS clear: %v", err)
}
require.NoError(t, err)
cfg = readIfcfg(t, dir, "eth0")
if _, ok := cfg["PEERDNS"]; ok {
t.Errorf("PEERDNS still present after clear: %q", cfg["PEERDNS"])
}
if _, ok := cfg["DNS1"]; ok {
t.Errorf("DNS1 still present after clear: %q", cfg["DNS1"])
}
_, ok := cfg["PEERDNS"]
assert.False(t, ok)
_, ok = cfg["DNS1"]
assert.False(t, ok)
}
// TestIfUpDownDNSEnsuresInterface verifies that SetIfaceDNS creates the
@ -102,30 +92,21 @@ func TestNetworkScriptsDNSPeerDNS(t *testing.T) {
func TestIfUpDownDNSEnsuresInterface(t *testing.T) {
dir := t.TempDir()
cfgPath := filepath.Join(dir, "interfaces")
if err := os.WriteFile(cfgPath, []byte("auto lo\niface lo inet loopback\n"), 0644); err != nil {
t.Fatal(err)
}
err := os.WriteFile(cfgPath, []byte("auto lo\niface lo inet loopback\n"), 0644)
require.NoError(t, err)
i := &ifUpDown{BaseConfig: cfgPath, BackupDir: cfgPath + ".backup"}
if err := i.ReadFile(cfgPath); err != nil {
t.Fatal(err)
}
require.NoError(t, i.ReadFile(cfgPath))
// eth0 is not present in the file; SetIfaceDNS must create it.
err := i.SetIfaceDNS(context.Background(), "eth0",
err = i.SetIfaceDNS(context.Background(), "eth0",
[]net.IP{net.ParseIP("1.1.1.1")}, []string{"example.com"})
if err != nil {
t.Fatalf("SetIfaceDNS: %v", err)
}
require.NoError(t, err)
// Re-read from disk and confirm the stanzas were persisted.
i.Interfaces = nil
if err := i.ReadFile(cfgPath); err != nil {
t.Fatal(err)
}
require.NoError(t, i.ReadFile(cfgPath))
interfaces, err := i.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
var found *Interface
for _, iface := range interfaces {
if iface.Name == "eth0" {
@ -133,13 +114,8 @@ func TestIfUpDownDNSEnsuresInterface(t *testing.T) {
break
}
}
if found == nil {
t.Fatal("eth0 was not persisted; SetIfaceDNS silently no-opped")
}
if len(found.DNS) != 1 || !found.DNS[0].Equal(net.ParseIP("1.1.1.1")) {
t.Errorf("DNS = %v, want [1.1.1.1]", found.DNS)
}
if len(found.SearchDomains) != 1 || found.SearchDomains[0] != "example.com" {
t.Errorf("SearchDomains = %v, want [example.com]", found.SearchDomains)
}
require.NotNil(t, found, "eth0 was not persisted; SetIfaceDNS silently no-opped")
require.Len(t, found.DNS, 1)
assert.True(t, found.DNS[0].Equal(net.ParseIP("1.1.1.1")), "DNS = %v, want [1.1.1.1]", found.DNS)
assert.Equal(t, []string{"example.com"}, found.SearchDomains)
}

4
go.mod
View file

@ -12,6 +12,7 @@ require (
github.com/kylelemons/godebug v1.1.0
github.com/prometheus-community/pro-bing v0.7.0
github.com/sirupsen/logrus v1.9.3
github.com/stretchr/testify v1.10.0
github.com/vishvananda/netlink v1.3.1
github.com/vishvananda/netns v0.0.5
golang.org/x/sys v0.37.0
@ -21,8 +22,9 @@ require (
)
require (
github.com/davecgh/go-spew v1.1.1 // indirect
github.com/google/uuid v1.6.0 // indirect
github.com/stretchr/testify v1.10.0 // indirect
github.com/pmezard/go-difflib v1.0.0 // indirect
golang.org/x/net v0.46.0 // indirect
golang.org/x/sync v0.17.0 // indirect
)

131
ifupdown.go
View file

@ -38,6 +38,96 @@ type ifUpDown struct {
backupRetention int
}
// stanzaFamily reports the address family this interface's stanza configures.
// "iface eth0 inet dhcp" configures IPv4, "iface eth0 inet6 static" IPv6. An
// interface this backend has not seen has no stanza and reports "".
func (iface *ifInterface) stanzaFamily() string {
fields := strings.Fields(iface.Mode)
if len(fields) == 0 {
return ""
}
switch fields[0] {
case "inet", "inet6":
return fields[0]
}
return ""
}
// dhcpState reports whether each family's DHCP client is enabled. A stanza only
// ever configures one family, so at most one of these is ever true.
func (iface *ifInterface) dhcpState() (dhcp4, dhcp6 bool) {
if !iface.isDHCP {
return false, false
}
family := iface.stanzaFamily()
return family == "inet", family == "inet6"
}
// setDHCP switches the stanza's method between "dhcp" and "static" for the
// family the stanza configures.
//
// Unlike netplan or networkd, an ifupdown interface is a set of stanzas and
// each names exactly one family, so this backend cannot express "DHCPv4 on,
// DHCPv6 on" from the single stanza it tracks per interface. Asking it to
// enable DHCP for the family its stanza does not configure is therefore an
// error rather than a silent no-op — the caller would otherwise be told the
// request succeeded while nothing was written. Disabling that other family is
// already true of a stanza that never configured it, so it is accepted.
func (iface *ifInterface) setDHCP(dhcp4, dhcp6 bool) error {
if iface.isPPP {
return fmt.Errorf("cannot change DHCP on PPP interface")
}
// An interface with no stanza yet gets one for the family being enabled.
family := iface.stanzaFamily()
if family == "" {
switch {
case dhcp4 && dhcp6:
return fmt.Errorf("ifupdown cannot enable DHCP for both families on one stanza")
case dhcp4:
iface.Mode = "inet dhcp"
iface.isDHCP = true
case dhcp6:
iface.Mode = "inet6 dhcp"
iface.isDHCP = true
default:
iface.Mode = "inet static"
iface.isDHCP = false
}
return nil
}
// Split the request into the family this stanza speaks for and the one it
// does not. Only the former can be honored.
enable, other := dhcp4, dhcp6
if family == "inet6" {
enable, other = dhcp6, dhcp4
}
if other {
return fmt.Errorf("ifupdown cannot enable DHCP for the other family on an %q stanza for %s", family, iface.Name)
}
fields := strings.Fields(iface.Mode)
method := ""
if len(fields) > 1 {
method = fields[1]
}
switch method {
case "loopback", "ppp", "tunnel", "wvdial":
return fmt.Errorf("cannot change DHCP on %q interface %s", method, iface.Name)
}
switch {
case enable && method != "dhcp":
iface.Mode = family + " dhcp"
iface.isDHCP = true
case !enable && method == "dhcp":
iface.Mode = family + " static"
iface.isDHCP = false
}
return nil
}
// Either retreives an existing interface, or makes a new one.
func (i *ifUpDown) EnsureInterface(name string) *ifInterface {
// Find existing interface and return it.
@ -637,6 +727,7 @@ func (i *ifUpDown) GetInterfaces() (interfaces []*Interface, err error) {
for _, iface := range i.Interfaces {
i := new(Interface)
i.Name = iface.Name
i.DHCP4, i.DHCP6 = iface.dhcpState()
// Discover the interface name and mac address.
for _, link := range links {
@ -983,6 +1074,41 @@ func (iface *ifInterface) Save(backupDir string, backupRetention int) error {
return nil
}
// Set the DHCP client state on an interface.
func (i *ifUpDown) SetIfaceDHCP(_ context.Context, iface string, dhcp4, dhcp6 bool) (err error) {
// Find or create the interface. A backend must not silently no-op just
// because it has not seen this interface before (e.g. a freshly attached
// NIC), otherwise the caller gets a success with no persisted change.
ifc := i.EnsureInterface(iface)
// Switching to DHCP hands addressing to the lease, so the static addresses
// and gateways the stanza carried are dropped rather than written back
// under a "dhcp" method that has no address option to hold them.
dhcp := dhcp4 || dhcp6
if err = ifc.setDHCP(dhcp4, dhcp6); err != nil {
return err
}
if dhcp {
ifc.Addresses = nil
ifc.Gateway4 = nil
ifc.Gateway6 = nil
}
// Save the interface config.
return ifc.Save(i.BackupDir, i.backupRetention)
}
// renewDHCP restarts the interface through ifupdown so the "dhcp" method that
// was just written to its stanza is acted on and a lease is acquired. ifup on
// an already-up interface is a no-op, so it is taken down first.
func (i *ifUpDown) renewDHCP(ctx context.Context, iface string) error {
// ifdown on an interface that is already down exits non-zero, which is not
// a failure of this call — down is the state ifup wants it in.
_, _ = runCommand(ctx, "ifdown", iface)
_, err := runCommand(ctx, "ifup", iface)
return err
}
// Set addresses to interface.
func (i *ifUpDown) SetIfaceAddresses(_ context.Context, iface string, addrs []*net.IPNet, gateway4, gateway6 net.IP) (err error) {
// Find the interface.
@ -991,7 +1117,10 @@ func (i *ifUpDown) SetIfaceAddresses(_ context.Context, iface string, addrs []*n
continue
}
// Ensure we can adjust addresses.
// Ensure we can adjust addresses. An ifupdown "dhcp" stanza takes no
// address option, so unlike netplan or networkd this backend cannot
// carry a static address alongside a lease on the same stanza. Call
// SetIfaceDHCP to convert the stanza to static first.
if ifc.isDHCP {
return fmt.Errorf("cannot change addresses on DHCP interface")
} else if ifc.isPPP {

78
ifupdown_test.go
View file

@ -6,46 +6,36 @@ import (
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/require"
)
// Validate the netplan configuration parser/writer functions.
func TestIfUpDown(t *testing.T) {
// Setup test file.
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
configPath := filepath.Join(tmpDir, "interfaces")
testDir, err := filepath.Abs("./tests/ifupdown")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
err = fileCopy(filepath.Join(testDir, "interfaces"), configPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup ifupdown and parse test file.
i := new(ifUpDown)
i.BaseConfig = configPath
i.BackupDir = configPath + ".backup"
err = i.ReadFile(i.BaseConfig)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err := i.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = i.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -62,9 +52,7 @@ func TestIfUpDown(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("203.0.113.6"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = i.SetIfaceRoutes(context.Background(), "test_eth1", []*Route{
@ -85,34 +73,24 @@ func TestIfUpDown(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify we can read the modified files.
i.Interfaces = nil
err = i.ReadFile(i.BaseConfig)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = i.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = i.SetIfaceAddresses(context.Background(), "test_backend", []*net.IPNet{
@ -121,44 +99,30 @@ func TestIfUpDown(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = i.SetIfaceRoutes(context.Background(), "test_eth0", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify we can read the modified files.
i.Interfaces = nil
err = i.ReadFile(i.BaseConfig)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = i.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}

110
netplan.go
View file

@ -94,6 +94,32 @@ type npInterface struct {
OVSParameters *map[string]interface{} `yaml:"openvswitch,omitempty"`
}
// dhcpState reports whether each family's DHCP client is enabled. An absent
// key means netplan's default, which is off.
func (c *npInterface) dhcpState() (dhcp4, dhcp6 bool) {
return c.DHCP4 != nil && *c.DHCP4, c.DHCP6 != nil && *c.DHCP6
}
// setDHCP records the requested DHCP client state for both families. Disabling
// a family drops its dhcp4-overrides/dhcp6-overrides, which netplan only reads
// while that client runs. A family being disabled that was already absent is
// left absent rather than written out as false, so reading and rewriting a
// config that never mentioned DHCP does not churn it.
func (c *npInterface) setDHCP(dhcp4, dhcp6 bool) {
if dhcp4 || c.DHCP4 != nil {
c.DHCP4 = boolPtr(dhcp4)
}
if !dhcp4 {
c.DHCP4Overrides = nil
}
if dhcp6 || c.DHCP6 != nil {
c.DHCP6 = boolPtr(dhcp6)
}
if !dhcp6 {
c.DHCP6Overrides = nil
}
}
// Physical ethernet configurations.
type npEthernet struct {
npPhysical `yaml:",inline"`
@ -198,10 +224,12 @@ type netplan struct {
backupRetention int
}
// Verify netplan exists, and try parsing its configurations.
func newNetplan(backupRetention int) (np *netplan, err error) {
// Calling netplan info will verify netplan is on the machine.
_, err = runCommand(context.Background(), "netplan", "info")
// Verify netplan exists, and try parsing its configurations. The `netplan info`
// probe is bound to ctx so a wedged netplan cannot stall construction.
func newNetplan(ctx context.Context, backupRetention int) (np *netplan, err error) {
// Calling netplan info will verify netplan is on the machine and working,
// not merely installed.
_, err = runCommand(ctx, "netplan", "info")
if err != nil {
return
}
@ -408,6 +436,7 @@ func (*netplan) ConvertInterface(name string, config npInterface, links []netlin
i.Name = name
i.MAC = mac
i.Link = foundLink
i.DHCP4, i.DHCP6 = config.dhcpState()
// Parse addresses.
for _, addr := range config.Addresses {
@ -808,6 +837,79 @@ func (np *netplan) SetIfaceAddresses(_ context.Context, iface string, addrs []*n
return
}
// Set the DHCP client state on an interface.
func (np *netplan) SetIfaceDHCP(_ context.Context, iface string, dhcp4, dhcp6 bool) (err error) {
// Update each config.
for _, c := range np.configs {
if c.empty {
continue
}
// Check ethernet interfaces.
for name, config := range c.Network.Ethernets {
// If the name is being changed in the config, use that as the name.
ifName := name
if config.SetName != "" {
ifName = config.SetName
}
if ifName != iface {
continue
}
c.dirty = true
config.setDHCP(dhcp4, dhcp6)
c.Network.Ethernets[name] = config
}
// Check Wifi interfaces.
for name, config := range c.Network.Wifis {
ifName := name
if config.SetName != "" {
ifName = config.SetName
}
if ifName != iface {
continue
}
c.dirty = true
config.setDHCP(dhcp4, dhcp6)
c.Network.Wifis[name] = config
}
// Check bridges.
if config, ok := c.Network.Bridges[iface]; ok {
c.dirty = true
config.setDHCP(dhcp4, dhcp6)
c.Network.Bridges[iface] = config
}
// Check bonds.
if config, ok := c.Network.Bonds[iface]; ok {
c.dirty = true
config.setDHCP(dhcp4, dhcp6)
c.Network.Bonds[iface] = config
}
// Check VLAN interfaces.
if config, ok := c.Network.VLANs[iface]; ok {
c.dirty = true
config.setDHCP(dhcp4, dhcp6)
c.Network.VLANs[iface] = config
}
}
// Try to save changes.
err = np.Save()
return
}
// renewDHCP makes netplan realize the configuration that was just written, so a
// newly enabled DHCP client starts and acquires a lease. `netplan apply` is the
// only supported way in; it reconciles every interface, not just this one, and
// so is a no-op for the interfaces whose configuration did not change.
func (np *netplan) renewDHCP(ctx context.Context, _ string) error {
_, err := runCommand(ctx, "netplan", "apply")
return err
}
// Set static routes to interface.
func (np *netplan) SetIfaceRoutes(_ context.Context, iface string, routes []*Route) (err error) {
// Update each config.

75
netplan_test.go
View file

@ -6,47 +6,36 @@ import (
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// Validate the netplan configuration parser/writer functions.
func TestNetplan(t *testing.T) {
// Setup test file.
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
configPath := filepath.Join(tmpDir, "netplan.yaml")
testDir, err := filepath.Abs("./tests/netplan")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
err = fileCopy(filepath.Join(testDir, "netplan.yaml"), configPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
err = fileCopy(filepath.Join(testDir, "netplan2.yaml"), filepath.Join(tmpDir, "netplan2.yaml"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Setup ifupdown and parse test file.
np, err := readNetplanConfigDirectory(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err := np.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Test setting the IP addresses on an interface.
err = np.SetIfaceAddresses(context.Background(), "test_eth0.1556", []*net.IPNet{
@ -63,9 +52,7 @@ func TestNetplan(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("1.2.3.1"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = np.SetIfaceRoutes(context.Background(), "test_eth3", []*Route{
@ -86,27 +73,19 @@ func TestNetplan(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = np.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Test setting the IP addresses on an interface.
err = np.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -115,37 +94,25 @@ func TestNetplan(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = np.SetIfaceRoutes(context.Background(), "test_eth0.1556", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = np.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}

220
networkConfigurator.go
View file

@ -4,6 +4,7 @@ import (
"context"
"fmt"
"net"
"sort"
"strings"
)
@ -24,13 +25,32 @@ func (i *Route) String() string {
}
type Interface struct {
Name string
MAC net.HardwareAddr
Addresses []*net.IPNet
Gateway4 net.IP
Gateway6 net.IP
Routes []*Route
DNS []net.IP
Name string
MAC net.HardwareAddr
Addresses []*net.IPNet
Gateway4 net.IP
Gateway6 net.IP
Routes []*Route
DNS []net.IP
// Up reports whether the interface can carry traffic right now, and
// Physical whether it is backed by a network device rather than created by
// the kernel or the hypervisor host — a bridge, bond, VLAN, tunnel, or the
// veth pair of a container is not physical, a virtio or vmxnet NIC is.
// Both describe the running system and are only set by GetInterfaces; the
// Interface values the configuration backends read back leave them false.
Up bool
Physical bool
// DHCP4 and DHCP6 report whether the interface runs a DHCP client for that
// address family. They describe the persisted configuration, not the
// running system: the kernel cannot be asked whether an address arrived
// from a lease, so these are read back from the configuration backends the
// same way DNS is. An interface can run a DHCP client and still carry
// static addresses of the same family.
DHCP4 bool
DHCP6 bool
SearchDomains []string
Link any
}
@ -59,15 +79,43 @@ type Configurator interface {
AddRoute(ctx context.Context, iface string, dst *net.IPNet, gateway net.IP, metric int) error
RemoveRoute(ctx context.Context, iface string, dst *net.IPNet, gateway net.IP) error
SetDNS(ctx context.Context, iface string, servers []net.IP, searchDomains []string) error
// SetDHCP turns each address family's DHCP client on or off. Both families
// are stated explicitly, so a caller moving an interface to DHCPv4 while
// keeping a static IPv6 address passes (true, false).
//
// Adding a static address does not imply disabling DHCP: every backend
// except ifupdown can carry static addresses alongside a lease, and which
// of the two the operator wants is not something AddAddress can infer.
// SetDHCP is how that choice is made.
//
// Enabling a family also asks the running system to acquire a lease now,
// rather than at the next reboot. Disabling one only rewrites the
// configuration: an interface's existing lease is left in place until it
// expires or the network is reconfigured, so the call cannot strand a
// caller that is connected over the leased address.
SetDHCP(ctx context.Context, iface string, dhcp4, dhcp6 bool) error
}
// ifaceBackend persists interface address, route, and DNS changes to an on-disk
// network configuration backend such as netplan, cloud-init, networkd,
// ifaceBackend persists interface address, route, DNS, and DHCP changes to an
// on-disk network configuration backend such as netplan, cloud-init, networkd,
// NetworkManager, RHEL network-scripts, or ifupdown.
type ifaceBackend interface {
SetIfaceAddresses(ctx context.Context, iface string, addrs []*net.IPNet, gateway4, gateway6 net.IP) error
SetIfaceRoutes(ctx context.Context, iface string, routes []*Route) error
SetIfaceDNS(ctx context.Context, iface string, servers []net.IP, searchDomains []string) error
SetIfaceDHCP(ctx context.Context, iface string, dhcp4, dhcp6 bool) error
}
// dhcpRenewer is an optional capability of a file backend: telling the running
// system to pick up a DHCP client that was just enabled in the configuration,
// so the interface acquires a lease without waiting for a reboot. Each backend
// implements it with its own manager's reconfigure command, which is both the
// least disruptive way to do it and the only one that will not fight the
// manager that owns the interface. cloud-init has no such command — it only
// runs at boot — and so does not implement this.
type dhcpRenewer interface {
renewDHCP(ctx context.Context, iface string) error
}
// panelBackend persists IP changes to a hosting control panel such as
@ -119,6 +167,12 @@ type ifaceDNSReader interface {
GetInterfaces() ([]*Interface, error)
}
// boolPtr returns a pointer to v, for the optional booleans in the netplan and
// cloud-init schemas where a nil pointer means "key absent" rather than false.
func boolPtr(v bool) *bool {
return &v
}
// ipIsIn reports whether ip is already present in addrs.
func ipIsIn(addrs []net.IP, ip net.IP) bool {
for _, a := range addrs {
@ -139,14 +193,18 @@ func stringInSlice(list []string, s string) bool {
return false
}
// mergeDNSFromBackends reads the DNS servers and search domains each backend
// has persisted and merges them into the matching runtime Interface (matched by
// name). The kernel/netlink layer does not track per-interface DNS, so the
// backends are the source of truth for these fields. Entries are de-duplicated
// so a host running several backends (e.g. netplan and cloud-init) does not
// list each resolver more than once. Per-backend errors are logged and do not
// abort the merge.
func mergeDNSFromBackends(backends []namedIfaceBackend, ifaces []*Interface) {
// mergeBackendState reads the DNS servers, search domains, and DHCP client
// state each backend has persisted and merges them into the matching runtime
// Interface (matched by name). The kernel/netlink layer tracks none of these —
// it cannot say which resolver an interface uses, nor whether an address came
// from a lease — so the backends are the source of truth for these fields.
//
// DNS entries are de-duplicated so a host running several backends (e.g.
// netplan and cloud-init) does not list each resolver more than once. The DHCP
// flags are OR'd for the same reason a lease is a property of the interface and
// not of the file describing it: if any backend has the client enabled, the
// interface runs one. Per-backend errors are logged and do not abort the merge.
func mergeBackendState(backends []namedIfaceBackend, ifaces []*Interface) {
byName := make(map[string]*Interface, len(ifaces))
for _, i := range ifaces {
byName[i.Name] = i
@ -166,6 +224,8 @@ func mergeDNSFromBackends(backends []namedIfaceBackend, ifaces []*Interface) {
if target == nil {
continue
}
target.DHCP4 = target.DHCP4 || bi.DHCP4
target.DHCP6 = target.DHCP6 || bi.DHCP6
for _, ip := range bi.DNS {
if ip == nil || ipIsIn(target.DNS, ip) {
continue
@ -182,6 +242,43 @@ func mergeDNSFromBackends(backends []namedIfaceBackend, ifaces []*Interface) {
}
}
// applyIfaceDHCP pushes the interface's DHCP client state to every registered
// file backend. Unlike the other apply helpers this one reports whether any
// backend accepted the change: a caller that is about to ask the running system
// for a lease needs to know that at least one configuration file now asks for
// one, otherwise the lease would be acquired and then lost on the next reboot.
// Individual failures are logged and do not abort the others, since each
// backend writes an independent configuration file — and ifupdown in particular
// rejects requests its one-stanza-per-family model cannot express.
func applyIfaceDHCP(ctx context.Context, backends []namedIfaceBackend, iface string, dhcp4, dhcp6 bool) (applied bool) {
for _, b := range backends {
if err := b.backend.SetIfaceDHCP(ctx, iface, dhcp4, dhcp6); err != nil {
logger.Printf("%s error: %v", b.name, err)
continue
}
applied = true
}
return applied
}
// renewDHCPOnBackends asks every backend that can reconfigure the running
// system to do so, so an interface whose DHCP client was just enabled acquires
// a lease now instead of at the next reboot. Backends that cannot — cloud-init,
// which only runs at boot — are skipped. Errors are logged rather than
// returned: the configuration has already been written, and a manager that
// declined to reconfigure has not undone that.
func renewDHCPOnBackends(ctx context.Context, backends []namedIfaceBackend, iface string) {
for _, b := range backends {
renewer, ok := b.backend.(dhcpRenewer)
if !ok {
continue
}
if err := renewer.renewDHCP(ctx, iface); err != nil {
logger.Printf("%s: error renewing DHCP on %s: %v", b.name, iface, err)
}
}
}
// applyIfaceDNS pushes the interface's DNS servers and search domains to every
// registered file backend, logging but not aborting on individual errors.
func applyIfaceDNS(ctx context.Context, backends []namedIfaceBackend, iface string, servers []net.IP, searchDomains []string) {
@ -243,6 +340,95 @@ func reorderPrimaryAddress(addrs []*net.IPNet, target *net.IPNet) ([]*net.IPNet,
return append([]*net.IPNet{target}, reordered...), true
}
// Interface name ranks, ordered by how likely a NIC of that kind is to be the
// one carrying a host's internet traffic.
const (
ifaceRankWired = iota
ifaceRankWireless
ifaceRankOther
)
// wiredNamePrefixes and wirelessNamePrefixes match the kernel's classic (eth0,
// wlan0) and predictable (eno1, ens3, enp1s0, enx.., em1, wlp2s0) names as well
// as the friendly names Windows reports ("Ethernet 2", "Wi-Fi"). Compared
// against a lower-cased name.
var (
wiredNamePrefixes = []string{"eth", "en", "em"}
wirelessNamePrefixes = []string{"wl", "wifi", "wi-fi"}
)
// FindPhysicalInterfaces returns the host's physical interfaces — leaving out
// the bridges, bonds, VLANs, tunnels, and container veth pairs that should
// never be handed a public address — ordered so the interface most likely to be
// the one a caller wants to configure for internet access comes first.
//
// Interfaces that are up sort ahead of those that are down, then those already
// carrying a default gateway (IPv4 ahead of IPv6-only), then wired ahead of
// wireless, and finally by name read the way a human reads it, so eth0 comes
// before eth1 and eth2 before eth10.
//
// This is a ranking rather than a decision: a caller looking for an interface
// that meets some further requirement — one not already holding a public
// address, say — filters the returned slice and takes the first survivor.
func FindPhysicalInterfaces(ifaces []*Interface) []*Interface {
physical := make([]*Interface, 0, len(ifaces))
for _, iface := range ifaces {
if iface.Physical {
physical = append(physical, iface)
}
}
sort.SliceStable(physical, func(i, j int) bool {
return preferInterface(physical[i], physical[j])
})
return physical
}
// preferInterface reports whether a should be offered ahead of b as the
// interface to configure for internet access.
func preferInterface(a, b *Interface) bool {
if a.Up != b.Up {
return a.Up
}
if ag, bg := gatewayRank(a), gatewayRank(b); ag != bg {
return ag < bg
}
if an, bn := ifaceNameRank(a.Name), ifaceNameRank(b.Name); an != bn {
return an < bn
}
return naturalLess(a.Name, b.Name)
}
// gatewayRank orders an interface by the default gateway it already carries.
// An interface the host currently reaches the internet over is the surest guess
// at the one it should keep reaching the internet over.
func gatewayRank(iface *Interface) int {
switch {
case iface.Gateway4 != nil:
return 0
case iface.Gateway6 != nil:
return 1
}
return 2
}
// ifaceNameRank guesses an interface's kind from its name. The name is all
// there is to go on: neither netlink nor the Windows IP Helper API reports
// whether a NIC is wired or wireless in a way that survives both platforms.
func ifaceNameRank(name string) int {
lower := strings.ToLower(name)
for _, p := range wirelessNamePrefixes {
if strings.HasPrefix(lower, p) {
return ifaceRankWireless
}
}
for _, p := range wiredNamePrefixes {
if strings.HasPrefix(lower, p) {
return ifaceRankWired
}
}
return ifaceRankOther
}
// Take a name and a list of interfaces and finds an interface by its name.
func FindInterfaceByName(name string, ifaces []*Interface) *Interface {
switch name {

236
networkConfigurator_test.go
View file

@ -5,14 +5,15 @@ import (
"errors"
"net"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
func mustCIDR(t *testing.T, s string) *net.IPNet {
t.Helper()
_, n, err := net.ParseCIDR(s)
if err != nil {
t.Fatalf("ParseCIDR(%q): %v", s, err)
}
require.NoError(t, err)
return n
}
@ -22,9 +23,7 @@ func TestRouteString(t *testing.T) {
Gateway: net.ParseIP("10.0.0.1"),
Metric: 100,
}
if got, want := r.String(), "10.0.0.0/24 via 10.0.0.1 metric 100"; got != want {
t.Errorf("Route.String() = %q, want %q", got, want)
}
assert.Equal(t, "10.0.0.0/24 via 10.0.0.1 metric 100", r.String())
}
func TestInterfaceString(t *testing.T) {
@ -38,11 +37,8 @@ func TestInterfaceString(t *testing.T) {
{Destination: mustCIDR(t, "10.0.0.0/24"), Gateway: net.ParseIP("10.0.0.1"), Metric: 5},
},
}
got := iface.String()
want := "Name: eth0 MAC: 00:11:22:33:44:55 Addresses: [192.168.1.0/24] Gateway4: 192.168.1.1 Gateway6: <nil> Routes: [10.0.0.0/24 via 10.0.0.1 metric 5]"
if got != want {
t.Errorf("Interface.String()\n got %q\nwant %q", got, want)
}
assert.Equal(t, want, iface.String())
}
func TestFindInterfaceByName(t *testing.T) {
@ -52,39 +48,104 @@ func TestFindInterfaceByName(t *testing.T) {
ifaces := []*Interface{eth1, eth0, pub6}
t.Run("by name", func(t *testing.T) {
if got := FindInterfaceByName("eth1", ifaces); got != eth1 {
t.Errorf("got %v, want eth1", got)
}
assert.Equal(t, eth1, FindInterfaceByName("eth1", ifaces))
})
t.Run("public picks gateway4 interface", func(t *testing.T) {
if got := FindInterfaceByName(Public, ifaces); got != eth0 {
t.Errorf("got %v, want eth0", got)
}
assert.Equal(t, eth0, FindInterfaceByName(Public, ifaces))
})
t.Run("public6 picks gateway6 interface", func(t *testing.T) {
if got := FindInterfaceByName(Public6, ifaces); got != pub6 {
t.Errorf("got %v, want pub6", got)
}
assert.Equal(t, pub6, FindInterfaceByName(Public6, ifaces))
})
t.Run("not found", func(t *testing.T) {
if got := FindInterfaceByName("missing", ifaces); got != nil {
t.Errorf("got %v, want nil", got)
}
assert.Nil(t, FindInterfaceByName("missing", ifaces))
})
t.Run("public with no gateway returns nil", func(t *testing.T) {
if got := FindInterfaceByName(Public, []*Interface{eth1}); got != nil {
t.Errorf("got %v, want nil", got)
}
assert.Nil(t, FindInterfaceByName(Public, []*Interface{eth1}))
})
t.Run("public6 with no gateway returns nil", func(t *testing.T) {
if got := FindInterfaceByName(Public6, []*Interface{eth1}); got != nil {
t.Errorf("got %v, want nil", got)
assert.Nil(t, FindInterfaceByName(Public6, []*Interface{eth1}))
})
}
// names extracts the interface names of a result slice, for comparing an
// expected ordering in one assertion.
func names(ifaces []*Interface) []string {
out := make([]string, 0, len(ifaces))
for _, iface := range ifaces {
out = append(out, iface.Name)
}
return out
}
func TestFindPhysicalInterfaces(t *testing.T) {
t.Run("drops virtual interfaces", func(t *testing.T) {
ifaces := []*Interface{
{Name: "docker0", Up: true},
{Name: "eth0", Up: true, Physical: true},
{Name: "veth1a2b", Up: true},
}
assert.Equal(t, []string{"eth0"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("up before down", func(t *testing.T) {
ifaces := []*Interface{
{Name: "eth0", Physical: true},
{Name: "eth1", Up: true, Physical: true},
}
assert.Equal(t, []string{"eth1", "eth0"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("gateway before none, v4 before v6", func(t *testing.T) {
ifaces := []*Interface{
{Name: "eth0", Up: true, Physical: true},
{Name: "eth1", Up: true, Physical: true, Gateway6: net.ParseIP("2001:db8::1")},
{Name: "eth2", Up: true, Physical: true, Gateway4: net.ParseIP("203.0.113.1")},
}
assert.Equal(t, []string{"eth2", "eth1", "eth0"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("up outranks a gateway on a down interface", func(t *testing.T) {
ifaces := []*Interface{
{Name: "eth0", Physical: true, Gateway4: net.ParseIP("203.0.113.1")},
{Name: "eth1", Up: true, Physical: true},
}
assert.Equal(t, []string{"eth1", "eth0"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("wired before wireless before other", func(t *testing.T) {
ifaces := []*Interface{
{Name: "ppp0", Up: true, Physical: true},
{Name: "wlp2s0", Up: true, Physical: true},
{Name: "enp1s0", Up: true, Physical: true},
}
assert.Equal(t, []string{"enp1s0", "wlp2s0", "ppp0"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("names ordered as a human reads them", func(t *testing.T) {
ifaces := []*Interface{
{Name: "eth10", Up: true, Physical: true},
{Name: "eth2", Up: true, Physical: true},
{Name: "eth0", Up: true, Physical: true},
}
assert.Equal(t, []string{"eth0", "eth2", "eth10"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("windows friendly names rank as wired and wireless", func(t *testing.T) {
ifaces := []*Interface{
{Name: "Wi-Fi", Up: true, Physical: true},
{Name: "Ethernet 2", Up: true, Physical: true},
}
assert.Equal(t, []string{"Ethernet 2", "Wi-Fi"}, names(FindPhysicalInterfaces(ifaces)))
})
t.Run("no physical interfaces returns empty", func(t *testing.T) {
assert.Empty(t, FindPhysicalInterfaces([]*Interface{{Name: "br0", Up: true}}))
assert.Empty(t, FindPhysicalInterfaces(nil))
})
}
@ -97,17 +158,6 @@ func TestReorderPrimaryAddress(t *testing.T) {
}
return out
}
equal := func(a, b []string) bool {
if len(a) != len(b) {
return false
}
for i := range a {
if a[i] != b[i] {
return false
}
}
return true
}
// hostIP keeps the host bits so IP.Equal matching is exercised, unlike the
// network address returned by mustCIDR.
@ -123,43 +173,27 @@ func TestReorderPrimaryAddress(t *testing.T) {
t.Run("middle moves to front", func(t *testing.T) {
got, ok := reorderPrimaryAddress([]*net.IPNet{a, b, c}, b)
if !ok {
t.Fatal("ok = false, want true")
}
if want := []string{"192.168.1.11", "192.168.1.10", "192.168.1.12"}; !equal(addrStrings(got), want) {
t.Errorf("got %v, want %v", addrStrings(got), want)
}
require.True(t, ok)
assert.Equal(t, []string{"192.168.1.11", "192.168.1.10", "192.168.1.12"}, addrStrings(got))
})
t.Run("already first is unchanged", func(t *testing.T) {
got, ok := reorderPrimaryAddress([]*net.IPNet{a, b, c}, a)
if !ok {
t.Fatal("ok = false, want true")
}
if want := []string{"192.168.1.10", "192.168.1.11", "192.168.1.12"}; !equal(addrStrings(got), want) {
t.Errorf("got %v, want %v", addrStrings(got), want)
}
require.True(t, ok)
assert.Equal(t, []string{"192.168.1.10", "192.168.1.11", "192.168.1.12"}, addrStrings(got))
})
t.Run("v6 target preserves v4 relative order", func(t *testing.T) {
got, ok := reorderPrimaryAddress([]*net.IPNet{a, b, v6}, v6)
if !ok {
t.Fatal("ok = false, want true")
}
if want := []string{"2001:db8::5", "192.168.1.10", "192.168.1.11"}; !equal(addrStrings(got), want) {
t.Errorf("got %v, want %v", addrStrings(got), want)
}
require.True(t, ok)
assert.Equal(t, []string{"2001:db8::5", "192.168.1.10", "192.168.1.11"}, addrStrings(got))
})
t.Run("absent target returns false", func(t *testing.T) {
got, ok := reorderPrimaryAddress([]*net.IPNet{a, b}, c)
if ok {
t.Error("ok = true, want false")
}
assert.False(t, ok)
// The original slice is returned unchanged.
if want := []string{"192.168.1.10", "192.168.1.11"}; !equal(addrStrings(got), want) {
t.Errorf("got %v, want %v", addrStrings(got), want)
}
assert.Equal(t, []string{"192.168.1.10", "192.168.1.11"}, addrStrings(got))
})
}
@ -168,10 +202,19 @@ type fakeIfaceBackend struct {
addrCalls int
routeCalls int
dnsCalls int
dhcpCalls int
lastAddrs []*net.IPNet
lastDHCP4 bool
lastDHCP6 bool
err error
}
func (f *fakeIfaceBackend) SetIfaceDHCP(_ context.Context, iface string, dhcp4, dhcp6 bool) error {
f.dhcpCalls++
f.lastDHCP4, f.lastDHCP6 = dhcp4, dhcp6
return f.err
}
func (f *fakeIfaceBackend) SetIfaceAddresses(_ context.Context, iface string, addrs []*net.IPNet, gateway4, gateway6 net.IP) error {
f.addrCalls++
f.lastAddrs = addrs
@ -221,9 +264,8 @@ func TestApplyIfaceAddresses(t *testing.T) {
{name: "ok", backend: ok},
}
applyIfaceAddresses(context.Background(), backends, "eth0", nil, nil, nil)
if failing.addrCalls != 1 || ok.addrCalls != 1 {
t.Errorf("addr calls: failing=%d ok=%d, want 1 each", failing.addrCalls, ok.addrCalls)
}
assert.Equal(t, 1, failing.addrCalls)
assert.Equal(t, 1, ok.addrCalls)
}
func TestApplyIfaceRoutes(t *testing.T) {
@ -234,9 +276,8 @@ func TestApplyIfaceRoutes(t *testing.T) {
{name: "ok", backend: ok},
}
applyIfaceRoutes(context.Background(), backends, "eth0", nil)
if failing.routeCalls != 1 || ok.routeCalls != 1 {
t.Errorf("route calls: failing=%d ok=%d, want 1 each", failing.routeCalls, ok.routeCalls)
}
assert.Equal(t, 1, failing.routeCalls)
assert.Equal(t, 1, ok.routeCalls)
}
func TestReloadPanels(t *testing.T) {
@ -247,9 +288,8 @@ func TestReloadPanels(t *testing.T) {
{name: "ok", backend: ok},
}
reloadPanels(context.Background(), backends)
if failing.reloadCalls != 1 || ok.reloadCalls != 1 {
t.Errorf("reload calls: failing=%d ok=%d, want 1 each", failing.reloadCalls, ok.reloadCalls)
}
assert.Equal(t, 1, failing.reloadCalls)
assert.Equal(t, 1, ok.reloadCalls)
}
func TestSetMainIPOnPanels(t *testing.T) {
@ -260,9 +300,8 @@ func TestSetMainIPOnPanels(t *testing.T) {
{name: "ok", backend: ok},
}
setMainIPOnPanels(context.Background(), backends, net.ParseIP("192.0.2.5"))
if failing.setMainIPCalls != 1 || ok.setMainIPCalls != 1 {
t.Errorf("setMainIP calls: failing=%d ok=%d, want 1 each", failing.setMainIPCalls, ok.setMainIPCalls)
}
assert.Equal(t, 1, failing.setMainIPCalls)
assert.Equal(t, 1, ok.setMainIPCalls)
}
func TestRemoveIPFromPanels(t *testing.T) {
@ -273,9 +312,8 @@ func TestRemoveIPFromPanels(t *testing.T) {
{name: "ok", backend: ok},
}
removeIPFromPanels(context.Background(), backends, net.ParseIP("192.0.2.5"))
if failing.removeIPCalls != 1 || ok.removeIPCalls != 1 {
t.Errorf("removeIP calls: failing=%d ok=%d, want 1 each", failing.removeIPCalls, ok.removeIPCalls)
}
assert.Equal(t, 1, failing.removeIPCalls)
assert.Equal(t, 1, ok.removeIPCalls)
}
// fakeDNSReaderBackend is a file backend that also reports back persisted
@ -292,48 +330,46 @@ func (f *fakeDNSReaderBackend) SetIfaceRoutes(context.Context, string, []*Route)
func (f *fakeDNSReaderBackend) SetIfaceDNS(context.Context, string, []net.IP, []string) error {
return nil
}
func (f *fakeDNSReaderBackend) GetInterfaces() ([]*Interface, error) { return f.ifaces, f.err }
func (f *fakeDNSReaderBackend) SetIfaceDHCP(context.Context, string, bool, bool) error { return nil }
func (f *fakeDNSReaderBackend) GetInterfaces() ([]*Interface, error) { return f.ifaces, f.err }
// mergeDNSFromBackends must union DNS from every backend into the matching
// runtime interface (by name), de-duplicate entries so multi-backend hosts do
// not list a resolver twice, skip backends with no matching interface, and keep
// going when one backend errors.
func TestMergeDNSFromBackends(t *testing.T) {
// mergeBackendState must union DNS from every backend into the matching runtime
// interface (by name), de-duplicate entries so multi-backend hosts do not list a
// resolver twice, OR the DHCP flags so a client enabled in any backend is
// reported, skip backends with no matching interface, and keep going when one
// backend errors.
func TestMergeBackendState(t *testing.T) {
runtime := []*Interface{{Name: "eth0"}, {Name: "eth1"}}
backends := []namedIfaceBackend{
{name: "broken", backend: &fakeDNSReaderBackend{err: errors.New("boom")}},
{name: "netplan", backend: &fakeDNSReaderBackend{ifaces: []*Interface{
{Name: "eth0", DNS: []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("2001:4860:4860::8888")}, SearchDomains: []string{"example.com"}},
{Name: "eth0", DNS: []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("2001:4860:4860::8888")}, SearchDomains: []string{"example.com"}, DHCP4: true},
}}},
{name: "cloud-init", backend: &fakeDNSReaderBackend{ifaces: []*Interface{
// Overlaps netplan (must dedupe) and adds one new entry.
{Name: "eth0", DNS: []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("1.1.1.1")}, SearchDomains: []string{"example.com", "corp.example"}},
// Overlaps netplan (must dedupe) and adds one new entry. DHCP4 is
// false here and must not clear the true netplan reported.
{Name: "eth0", DNS: []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("1.1.1.1")}, SearchDomains: []string{"example.com", "corp.example"}, DHCP6: true},
}}},
{name: "ifupdown", backend: &fakeDNSReaderBackend{ifaces: []*Interface{
{Name: "eth1", DNS: []net.IP{net.ParseIP("9.9.9.9")}, SearchDomains: []string{"a.test"}},
// No runtime match; must be ignored.
{Name: "eth9", DNS: []net.IP{net.ParseIP("10.0.0.1")}},
{Name: "eth9", DNS: []net.IP{net.ParseIP("10.0.0.1")}, DHCP4: true},
}}},
}
mergeDNSFromBackends(backends, runtime)
mergeBackendState(backends, runtime)
eth0 := runtime[0]
wantDNS := []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("2001:4860:4860::8888"), net.ParseIP("1.1.1.1")}
if !equalIPs(eth0.DNS, wantDNS) {
t.Errorf("eth0 DNS = %v, want %v", eth0.DNS, wantDNS)
}
assert.True(t, equalIPs(eth0.DNS, wantDNS))
wantSearch := []string{"example.com", "corp.example"}
if len(eth0.SearchDomains) != len(wantSearch) || eth0.SearchDomains[0] != wantSearch[0] || eth0.SearchDomains[1] != wantSearch[1] {
t.Errorf("eth0 SearchDomains = %v, want %v", eth0.SearchDomains, wantSearch)
}
assert.Equal(t, wantSearch, eth0.SearchDomains)
assert.True(t, eth0.DHCP4, "netplan reported DHCP4; cloud-init's false must not clear it")
assert.True(t, eth0.DHCP6, "cloud-init reported DHCP6")
eth1 := runtime[1]
if !equalIPs(eth1.DNS, []net.IP{net.ParseIP("9.9.9.9")}) {
t.Errorf("eth1 DNS = %v, want [9.9.9.9]", eth1.DNS)
}
if len(eth1.SearchDomains) != 1 || eth1.SearchDomains[0] != "a.test" {
t.Errorf("eth1 SearchDomains = %v, want [a.test]", eth1.SearchDomains)
}
assert.True(t, equalIPs(eth1.DNS, []net.IP{net.ParseIP("9.9.9.9")}))
assert.Equal(t, []string{"a.test"}, eth1.SearchDomains)
assert.False(t, eth1.DHCP4, "eth9's DHCP4 must not leak onto eth1")
}
func equalIPs(a, b []net.IP) bool {

234
networkManager.go
View file

@ -6,8 +6,10 @@ import (
"fmt"
"net"
"strings"
"time"
"github.com/Wifx/gonetworkmanager/v3"
"github.com/godbus/dbus/v5"
"github.com/vishvananda/netlink"
)
@ -15,6 +17,8 @@ type nmConnection struct {
ID string
Name string
UsingData bool
Method4 string
Method6 string
Addresses4 []*net.IPNet
Addresses6 []*net.IPNet
Gateway4 net.IP
@ -25,6 +29,35 @@ type nmConnection struct {
DNSSearch []string
}
// dhcpState reports whether each family's DHCP client is enabled. IPv4 "auto"
// means DHCPv4. For IPv6, "auto" means router advertisements plus DHCPv6 when
// the router asks for it, and "dhcp" means DHCPv6 alone; both run a client.
func (c *nmConnection) dhcpState() (dhcp4, dhcp6 bool) {
dhcp4 = c.Method4 == "auto"
dhcp6 = c.Method6 == "auto" || c.Method6 == "dhcp"
return dhcp4, dhcp6
}
// nmStaticMethod4 is the ipv4.method to leave behind when DHCPv4 is turned off:
// "manual" when the connection still carries static addresses to serve, and
// "disabled" when turning off the lease leaves it with no IPv4 at all.
func nmStaticMethod4(hasAddrs bool) string {
if hasAddrs {
return "manual"
}
return "disabled"
}
// nmStaticMethod6 is the ipv6.method counterpart. An IPv6 interface with no
// addresses keeps its link-local one rather than losing IPv6 entirely, which is
// what "disabled" would do.
func nmStaticMethod6(hasAddrs bool) string {
if hasAddrs {
return "manual"
}
return "link-local"
}
type networkManager struct {
config gonetworkmanager.Settings
}
@ -90,6 +123,11 @@ func (*networkManager) ParseConnection(settings gonetworkmanager.ConnectionSetti
}
conn.Name = name
// Get the addressing method of each family. These decide whether a DHCP
// client runs, independently of any static addresses parsed below.
conn.Method4, _ = settings["ipv4"]["method"].(string)
conn.Method6, _ = settings["ipv6"]["method"].(string)
// Get the IPv4 address map, and confirm the newer configuration style is used.
addrMap, ok := settings["ipv4"]["address-data"]
if ok {
@ -259,8 +297,62 @@ func (*networkManager) ParseConnection(settings gonetworkmanager.ConnectionSetti
return
}
// Verify netplan exists, and try parsing its configurations.
func newNetworkManager() (nm *networkManager, err error) {
// nmBusName is the well-known D-Bus name the NetworkManager daemon takes once
// it is running. Until some process owns it, there is nothing on the bus to
// answer a configuration call.
const nmBusName = "org.freedesktop.NetworkManager"
// nmBusNameOwned reports whether the NetworkManager daemon currently owns its
// bus name — the "is the socket live" question. It is asked before any property
// is read, because NetworkManager is D-Bus activatable: reading a property on
// an unowned name asks the bus to *start* the daemon. Waiting for a service to
// come up on its own must not be the thing that launches it.
func nmBusNameOwned(conn *dbus.Conn) (bool, error) {
var owned bool
err := conn.BusObject().Call("org.freedesktop.DBus.NameHasOwner", 0, nmBusName).Store(&owned)
return owned, err
}
// networkManagerReady reports whether NetworkManager is on the bus and has
// finished starting up. The two are distinct: the daemon takes its bus name
// early, then spends a while bringing up the connections it is configured to
// activate at boot. Its Startup property stays true for that window, and a
// connection modified during it can be overwritten as startup completes.
//
// A missing system bus is reported as "not ready" rather than as a hard error,
// because a host early enough in boot to beat NetworkManager can also be early
// enough to beat dbus-daemon.
func networkManagerReady() (bool, error) {
conn, err := dbus.SystemBus()
if err != nil {
return false, err
}
owned, err := nmBusNameOwned(conn)
if err != nil || !owned {
return false, err
}
daemon, err := gonetworkmanager.NewNetworkManager()
if err != nil {
return false, err
}
startup, err := daemon.GetPropertyStartup()
if err != nil {
return false, err
}
return !startup, nil
}
// newNetworkManager waits for the NetworkManager daemon to be ready, then opens
// its settings interface. Unlike the file backends, NetworkManager is
// configured through a running daemon, so a configurator built while it is
// still starting would hold a settings handle that reports no connections and
// accepts no changes.
func newNetworkManager(ctx context.Context, readyTimeout time.Duration) (nm *networkManager, err error) {
if err = waitForServiceReady(ctx, "NetworkManager", readyTimeout, networkManagerReady); err != nil {
return nil, err
}
config, err := gonetworkmanager.NewSettings()
if err != nil {
return
@ -326,6 +418,7 @@ func (nm *networkManager) GetInterfaces() (interfaces []*Interface, err error) {
i.Name = connection.Name
i.MAC = mac
i.Link = foundLink
i.DHCP4, i.DHCP6 = connection.dhcpState()
// Append addresses.
for _, addr := range connection.Addresses4 {
@ -408,44 +501,125 @@ func (nm *networkManager) SetIfaceAddresses(ctx context.Context, iface string, a
return
}
// Read the current addressing method of each family. NetworkManager
// serves static addresses alongside a lease when the method is "auto",
// so a connection already on DHCP keeps it: changing an address is not
// a request to stop using DHCP, and SetIfaceDHCP is how that is asked
// for. Only a family that is not already leasing is moved to "manual"
// (or off, when it is left with no addresses at all).
method4, _ := settings["ipv4"]["method"].(string)
method6, _ := settings["ipv6"]["method"].(string)
conn := &nmConnection{Method4: method4, Method6: method6}
dhcp4, dhcp6 := conn.dhcpState()
// Update address list for IPv4.
if len(addrs4) == 0 {
_, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv4.method", "disabled", "ipv4.addresses", "", "ipv4.gateway", "")
if err != nil {
errs = append(errs, fmt.Errorf("failed to disable ipv4 on %s: %w", id, err))
}
} else {
gateway4S := ""
if gateway4 != nil {
gateway4S = gateway4.String()
}
_, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv4.method", "manual", "ipv4.addresses", strings.Join(addrs4, ","), "ipv4.gateway", gateway4S)
if err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv4.addresses on %s: %w", id, err))
}
newMethod4 := nmStaticMethod4(len(addrs4) != 0)
if dhcp4 {
newMethod4 = "auto"
}
gateway4S := ""
if gateway4 != nil && len(addrs4) != 0 {
gateway4S = gateway4.String()
}
_, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv4.method", newMethod4, "ipv4.addresses", strings.Join(addrs4, ","), "ipv4.gateway", gateway4S)
if err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv4.addresses on %s: %w", id, err))
}
// Update address list for IPv6.
if len(addrs6) == 0 {
_, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv6.method", "link-local", "ipv6.addresses", "", "ipv6.gateway", "")
if err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv6 link-local on %s: %w", id, err))
}
} else {
gateway6S := ""
if gateway6 != nil {
gateway6S = gateway6.String()
}
_, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv6.method", "manual", "ipv6.addresses", strings.Join(addrs6, ","), "ipv6.gateway", gateway6S)
if err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv6.addresses on %s: %w", id, err))
}
newMethod6 := nmStaticMethod6(len(addrs6) != 0)
if dhcp6 {
newMethod6 = method6
}
gateway6S := ""
if gateway6 != nil && len(addrs6) != 0 {
gateway6S = gateway6.String()
}
_, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv6.method", newMethod6, "ipv6.addresses", strings.Join(addrs6, ","), "ipv6.gateway", gateway6S)
if err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv6.addresses on %s: %w", id, err))
}
}
return errors.Join(errs...)
}
// Set the DHCP client state on an interface.
func (nm *networkManager) SetIfaceDHCP(ctx context.Context, iface string, dhcp4, dhcp6 bool) (err error) {
// Get connections from NM.
connections, err := nm.config.ListConnections()
if err != nil {
return err
}
var errs []error
// Find the connections that has the interfaces.
for _, c := range connections {
// Get the settings of the connection.
var settings gonetworkmanager.ConnectionSettings
settings, err = c.GetSettings()
if err != nil {
return err
}
// Get the interface name.
name, ok := settings["connection"]["interface-name"].(string)
if !ok || name != iface {
continue
}
// Get the interface id.
id, ok := settings["connection"]["id"].(string)
if !ok {
return fmt.Errorf("failed to get interface id")
}
// Parse the connection so turning a lease off can fall back to the
// method that still serves whatever static addresses it holds.
conn, parseErr := nm.ParseConnection(settings)
if parseErr != nil {
errs = append(errs, fmt.Errorf("failed to parse connection %s: %w", id, parseErr))
continue
}
// Switch the IPv4 method. "auto" is DHCPv4; NetworkManager keeps
// serving any ipv4.addresses the connection carries alongside it.
method4 := "auto"
if !dhcp4 {
method4 = nmStaticMethod4(len(conn.Addresses4) != 0)
}
if _, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv4.method", method4); err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv4.method on %s: %w", id, err))
}
// Switch the IPv6 method. A connection already on "auto" is left there
// rather than forced to "dhcp": both run a DHCPv6 client, and "auto"
// additionally honors router advertisements, which turning it into
// "dhcp" would silently switch off.
method6 := "auto"
if dhcp6 && conn.Method6 == "dhcp" {
method6 = "dhcp"
} else if !dhcp6 {
method6 = nmStaticMethod6(len(conn.Addresses6) != 0)
}
if _, err = runCommand(ctx, "nmcli", "connection", "modify", id, "ipv6.method", method6); err != nil {
errs = append(errs, fmt.Errorf("failed to set ipv6.method on %s: %w", id, err))
}
}
return errors.Join(errs...)
}
// renewDHCP has NetworkManager reapply the connection profile to the device, so
// a client it was just told to run starts and acquires a lease. `device
// reapply` changes the device in place and, unlike `connection up`, does not
// tear the link down first.
func (nm *networkManager) renewDHCP(ctx context.Context, iface string) error {
_, err := runCommand(ctx, "nmcli", "device", "reapply", iface)
return err
}
// Set static routes to interface.
func (nm *networkManager) SetIfaceRoutes(ctx context.Context, iface string, routes []*Route) (err error) {
// Build route slices.

73
networkManager_test.go
View file

@ -10,6 +10,8 @@ import (
"github.com/Wifx/gonetworkmanager/v3"
"github.com/godbus/dbus/v5"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
type mockNMConnection struct {
@ -321,9 +323,7 @@ func TestNetworkManager(t *testing.T) {
// Setup test file.
tmpDir := "/tmp/networkManager-netconfig-Test"
testDir, err := filepath.Abs("./tests/networkManager")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
// Update the PATH environment variable so that our nmcli is used instead of the systems.
@ -336,15 +336,11 @@ func TestNetworkManager(t *testing.T) {
// Get the interfaces state.
interfaces, err := n.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = n.SetIfaceAddresses(context.Background(), "test_eth0.1556", []*net.IPNet{
@ -361,9 +357,7 @@ func TestNetworkManager(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("1.2.3.1"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = n.SetIfaceRoutes(context.Background(), "test_eth2", []*Route{
@ -384,9 +378,7 @@ func TestNetworkManager(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting DNS on an interface; static DNS should disable automatic DNS.
err = n.SetIfaceDNS(context.Background(), "test_eth0", []net.IP{
@ -394,15 +386,11 @@ func TestNetworkManager(t *testing.T) {
net.ParseIP("1.1.1.1"),
net.ParseIP("2001:4860:4860::8888"),
}, []string{"example.com"})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = n.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -411,27 +399,19 @@ func TestNetworkManager(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = n.SetIfaceRoutes(context.Background(), "test_eth0.1556", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}
// nmNameservers must read the modern dns-data (strings) as well as the legacy
@ -445,30 +425,21 @@ func TestNMDNSParsing(t *testing.T) {
}
got := nmNameservers(group)
want := []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("1.1.1.1")}
if !equalIPs(got, want) {
t.Errorf("dns-data = %v, want %v", got, want)
}
if search := nmSearchDomains(group); len(search) != 2 || search[0] != "a.test" || search[1] != "b.test" {
t.Errorf("dns-search = %v, want [a.test b.test]", search)
}
assert.Truef(t, equalIPs(got, want), "dns-data = %v, want %v", got, want)
search := nmSearchDomains(group)
assert.Falsef(t, len(search) != 2 || search[0] != "a.test" || search[1] != "b.test", "dns-search = %v, want [a.test b.test]", search)
// Legacy ipv4 "dns" as []uint32 (decoded via uint2IP, matching addresses).
ipv4Legacy := map[string]any{"dns": []uint32{ip2Uint(net.ParseIP("1.2.3.4"))}}
if got := nmNameservers(ipv4Legacy); len(got) != 1 || !got[0].Equal(net.ParseIP("1.2.3.4")) {
t.Errorf("legacy ipv4 dns = %v, want [1.2.3.4]", got)
}
gotV4 := nmNameservers(ipv4Legacy)
assert.Falsef(t, len(gotV4) != 1 || !gotV4[0].Equal(net.ParseIP("1.2.3.4")), "legacy ipv4 dns = %v, want [1.2.3.4]", gotV4)
// Legacy ipv6 "dns" as [][]byte.
ipv6Legacy := map[string]any{"dns": [][]byte{net.ParseIP("2001:4860:4860::8888").To16()}}
if got := nmNameservers(ipv6Legacy); len(got) != 1 || !got[0].Equal(net.ParseIP("2001:4860:4860::8888")) {
t.Errorf("legacy ipv6 dns = %v, want [2001:4860:4860::8888]", got)
}
gotV6 := nmNameservers(ipv6Legacy)
assert.Falsef(t, len(gotV6) != 1 || !gotV6[0].Equal(net.ParseIP("2001:4860:4860::8888")), "legacy ipv6 dns = %v, want [2001:4860:4860::8888]", gotV6)
// Empty group yields nothing.
if v := nmNameservers(map[string]any{}); len(v) != 0 {
t.Errorf("empty group dns = %v, want empty", v)
}
if v := nmSearchDomains(map[string]any{}); len(v) != 0 {
t.Errorf("empty group dns-search = %v, want empty", v)
}
assert.Emptyf(t, nmNameservers(map[string]any{}), "empty group dns, want empty")
assert.Emptyf(t, nmSearchDomains(map[string]any{}), "empty group dns-search, want empty")
}

79
networkScripts.go
View file

@ -44,6 +44,43 @@ type networkScripts struct {
backupRetention int
}
// nsDHCPState reports whether an ifcfg file's keys enable a DHCP client for
// each family. BOOTPROTO names the IPv4 method — "dhcp" and the near-extinct
// "bootp" are the dynamic ones, and any other value, including an absent key,
// means the address is configured statically. The IPv6 client is separate and
// off unless DHCPV6C says otherwise.
func nsDHCPState(config map[string]string) (dhcp4, dhcp6 bool) {
switch strings.ToLower(config["BOOTPROTO"]) {
case "dhcp", "bootp":
dhcp4 = true
}
switch strings.ToLower(config["DHCPV6C"]) {
case "yes", "true", "1":
dhcp6 = true
}
return dhcp4, dhcp6
}
// nsSetDHCP writes the DHCP client state into an ifcfg config map. Disabling
// IPv4 leaves BOOTPROTO=none rather than deleting it: unlike the netplan and
// networkd schemas, an absent BOOTPROTO is read by some initscript versions as
// a prompt to guess, and "none" states the intent. PERSISTENT_DHCLIENT only has
// meaning while the IPv4 client runs, so it goes with it.
func nsSetDHCP(config map[string]string, dhcp4, dhcp6 bool) {
if dhcp4 {
config["BOOTPROTO"] = "dhcp"
} else {
config["BOOTPROTO"] = "none"
delete(config, "PERSISTENT_DHCLIENT")
}
if dhcp6 {
config["IPV6INIT"] = "yes"
config["DHCPV6C"] = "yes"
} else {
delete(config, "DHCPV6C")
}
}
// Either retreives an existing interface, or makes a new one.
func (ns *networkScripts) EnsureInterface(name string) *nsInterface {
// Find existing interface and return it.
@ -523,6 +560,12 @@ func (ns *networkScripts) GetInterfaces() (interfaces []*Interface, err error) {
// Parse interface files.
for _, file := range iface.IFFiles {
// Read the DHCP client state. Any of an interface's files enabling
// a client means the interface runs one.
dhcp4, dhcp6 := nsDHCPState(file.Config)
i.DHCP4 = i.DHCP4 || dhcp4
i.DHCP6 = i.DHCP6 || dhcp6
// Parse IPv4 addresses in the file.
ipAddr := ns.ParseIP(file.Config, "")
if ipAddr != nil {
@ -830,6 +873,42 @@ func (ns *networkScripts) SetIfaceAddresses(_ context.Context, iface string, add
return
}
// Set the DHCP client state on an interface.
func (ns *networkScripts) SetIfaceDHCP(_ context.Context, iface string, dhcp4, dhcp6 bool) (err error) {
// Find or create the interface. A backend must not silently no-op just
// because it has not seen this interface before (e.g. a freshly attached
// NIC), otherwise the caller gets a success with no persisted change.
ifc := ns.EnsureInterface(iface)
// Merge configs.
config := make(map[string]string)
for _, file := range ifc.IFFiles {
err = mergo.Merge(&config, file.Config)
if err != nil {
return err
}
}
nsSetDHCP(config, dhcp4, dhcp6)
// Try to save.
return ifc.Save(config, ns.ConfigDir, ns.backupRetention)
}
// renewDHCP restarts the interface through the initscripts so the DHCP client
// that was just written to its ifcfg file is started. `ifup` on an interface
// that is already up is a no-op on these distributions, so it is taken down
// first; this is the same ifdown/ifup pair the initscripts themselves use, and
// it is what acquires the lease.
func (ns *networkScripts) renewDHCP(ctx context.Context, iface string) error {
// ifdown on an interface that is already down exits non-zero. That is not a
// failure of this call — the interface being down is the state ifup wants —
// so only the ifup result decides.
_, _ = runCommand(ctx, "ifdown", iface)
_, err := runCommand(ctx, "ifup", iface)
return err
}
// Set static routes to interface.
func (ns *networkScripts) SetIfaceRoutes(_ context.Context, iface string, routes []*Route) (err error) {
// Build route slices.

82
networkScripts_test.go
View file

@ -7,26 +7,22 @@ import (
"path/filepath"
"strings"
"testing"
"github.com/stretchr/testify/require"
)
// Validate the network scripts configuration parser/writer functions.
func TestNetworkScripts(t *testing.T) {
// Setup test file.
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
testDir, err := filepath.Abs("./tests/networkScripts")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
// Try to read the test directory for files to copy to our temporary directory.
entries, err := os.ReadDir(testDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
for _, entry := range entries {
if !strings.HasPrefix(entry.Name(), "ifcfg-") && !strings.HasPrefix(entry.Name(), "route-") && !strings.HasPrefix(entry.Name(), "route6-") {
continue
@ -35,28 +31,20 @@ func TestNetworkScripts(t *testing.T) {
configPath := filepath.Join(testDir, entry.Name())
tmpPath := filepath.Join(tmpDir, entry.Name())
err = fileCopy(configPath, tmpPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}
// Setup ifupdown and parse test file.
ns, err := newNetworkScriptsWithConfig(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err := ns.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = ns.SetIfaceAddresses(context.Background(), "test_eth0.1556", []*net.IPNet{
@ -73,9 +61,7 @@ func TestNetworkScripts(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("1.2.3.1"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = ns.SetIfaceRoutes(context.Background(), "test_eth2", []*Route{
@ -96,33 +82,23 @@ func TestNetworkScripts(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify we can re-read configurations.
ns, err = newNetworkScriptsWithConfig(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = ns.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Test setting the IP addresses on an interface.
err = ns.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -131,43 +107,29 @@ func TestNetworkScripts(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = ns.SetIfaceRoutes(context.Background(), "test_eth0.1556", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify we can re-read configurations.
ns, err = newNetworkScriptsWithConfig(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = ns.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
require.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}

98
networkScripts_unit_test.go
View file

@ -3,6 +3,9 @@ package netconfig
import (
"net"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// parseIPRoutes is a pure transform from raw whitespace-split route fields to
@ -12,40 +15,29 @@ func TestParseIPRoutes(t *testing.T) {
routes := parseIPRoutes([][]string{
{"10.0.0.0/24", "via", "10.0.0.1", "metric", "100"},
})
if len(routes) != 1 {
t.Fatalf("got %d routes, want 1", len(routes))
}
require.Len(t, routes, 1)
r := routes[0]
if got := r.Destination.String(); got != "10.0.0.0/24" {
t.Errorf("destination = %s, want 10.0.0.0/24", got)
}
if !r.Gateway.Equal(net.ParseIP("10.0.0.1")) {
t.Errorf("gateway = %s, want 10.0.0.1", r.Gateway)
}
if r.Metric != 100 {
t.Errorf("metric = %d, want 100", r.Metric)
}
assert.Equal(t, "10.0.0.0/24", r.Destination.String())
assert.True(t, r.Gateway.Equal(net.ParseIP("10.0.0.1")))
assert.Equal(t, 100, r.Metric)
})
t.Run("default metric when absent", func(t *testing.T) {
routes := parseIPRoutes([][]string{{"10.0.0.0/24", "via", "10.0.0.1"}})
if len(routes) != 1 || routes[0].Metric != 256 {
t.Fatalf("expected single route with default metric 256, got %+v", routes)
}
require.Len(t, routes, 1)
assert.Equal(t, 256, routes[0].Metric)
})
t.Run("metric zero falls back to default", func(t *testing.T) {
routes := parseIPRoutes([][]string{{"10.0.0.0/24", "metric", "0"}})
if len(routes) != 1 || routes[0].Metric != 256 {
t.Fatalf("expected default metric 256 for metric 0, got %+v", routes)
}
require.Len(t, routes, 1)
assert.Equal(t, 256, routes[0].Metric)
})
t.Run("invalid metric falls back to default", func(t *testing.T) {
routes := parseIPRoutes([][]string{{"10.0.0.0/24", "metric", "notanumber"}})
if len(routes) != 1 || routes[0].Metric != 256 {
t.Fatalf("expected default metric 256 for bad metric, got %+v", routes)
}
require.Len(t, routes, 1)
assert.Equal(t, 256, routes[0].Metric)
})
t.Run("empty and invalid entries are skipped", func(t *testing.T) {
@ -55,12 +47,8 @@ func TestParseIPRoutes(t *testing.T) {
{"10.0.0.0/24", "via", "nope"}, // bad gateway: skipped
{"192.168.0.0/16", "via", "192.168.0.1"}, // valid
})
if len(routes) != 1 {
t.Fatalf("got %d routes, want 1", len(routes))
}
if got := routes[0].Destination.String(); got != "192.168.0.0/16" {
t.Errorf("destination = %s, want 192.168.0.0/16", got)
}
require.Len(t, routes, 1)
assert.Equal(t, "192.168.0.0/16", routes[0].Destination.String())
})
}
@ -69,67 +57,45 @@ func TestNetworkScriptsParseIP(t *testing.T) {
ns := &networkScripts{}
t.Run("missing IPADDR returns nil", func(t *testing.T) {
if got := ns.ParseIP(map[string]string{}, ""); got != nil {
t.Errorf("got %v, want nil", got)
}
assert.Nil(t, ns.ParseIP(map[string]string{}, ""))
})
t.Run("empty IPADDR returns nil", func(t *testing.T) {
if got := ns.ParseIP(map[string]string{"IPADDR": ""}, ""); got != nil {
t.Errorf("got %v, want nil", got)
}
assert.Nil(t, ns.ParseIP(map[string]string{"IPADDR": ""}, ""))
})
t.Run("explicit prefix", func(t *testing.T) {
got := ns.ParseIP(map[string]string{"IPADDR": "192.168.1.5", "PREFIX": "24"}, "")
if got == nil {
t.Fatal("got nil")
}
if !got.IP.Equal(net.ParseIP("192.168.1.5")) {
t.Errorf("IP = %s, want 192.168.1.5", got.IP)
}
if ones, _ := got.Mask.Size(); ones != 24 {
t.Errorf("prefix = %d, want 24", ones)
}
require.NotNil(t, got)
assert.True(t, got.IP.Equal(net.ParseIP("192.168.1.5")))
ones, _ := got.Mask.Size()
assert.Equal(t, 24, ones)
})
t.Run("prefix derived from netmask", func(t *testing.T) {
got := ns.ParseIP(map[string]string{"IPADDR": "10.1.2.3", "NETMASK": "255.255.255.0"}, "")
if got == nil {
t.Fatal("got nil")
}
if ones, _ := got.Mask.Size(); ones != 24 {
t.Errorf("prefix = %d, want 24 (from netmask)", ones)
}
require.NotNil(t, got)
ones, _ := got.Mask.Size()
assert.Equal(t, 24, ones)
})
t.Run("defaults to /16 with no prefix or netmask", func(t *testing.T) {
got := ns.ParseIP(map[string]string{"IPADDR": "10.1.2.3"}, "")
if got == nil {
t.Fatal("got nil")
}
if ones, _ := got.Mask.Size(); ones != 16 {
t.Errorf("prefix = %d, want default 16", ones)
}
require.NotNil(t, got)
ones, _ := got.Mask.Size()
assert.Equal(t, 16, ones)
})
t.Run("indexed keys", func(t *testing.T) {
cfg := map[string]string{"IPADDR0": "172.16.0.9", "PREFIX0": "30"}
got := ns.ParseIP(cfg, "0")
if got == nil {
t.Fatal("got nil")
}
if !got.IP.Equal(net.ParseIP("172.16.0.9")) {
t.Errorf("IP = %s, want 172.16.0.9", got.IP)
}
if ones, _ := got.Mask.Size(); ones != 30 {
t.Errorf("prefix = %d, want 30", ones)
}
require.NotNil(t, got)
assert.True(t, got.IP.Equal(net.ParseIP("172.16.0.9")))
ones, _ := got.Mask.Size()
assert.Equal(t, 30, ones)
})
t.Run("invalid address returns nil", func(t *testing.T) {
if got := ns.ParseIP(map[string]string{"IPADDR": "not-an-ip", "PREFIX": "24"}, ""); got != nil {
t.Errorf("got %v, want nil", got)
}
assert.Nil(t, ns.ParseIP(map[string]string{"IPADDR": "not-an-ip", "PREFIX": "24"}, ""))
})
}

96
networkd.go
View file

@ -31,6 +31,56 @@ type networkd struct {
backupRetention int
}
// parseNetworkdDHCP reports which families a [Network] DHCP= value enables.
// systemd.network(5) documents "yes", "no", "ipv4" and "ipv6"; the boolean
// spellings and the pre-v243 aliases "both"/"none" are still accepted by
// systemd and still appear in configs written by older tooling, so they are
// recognised here too. An unset or unrecognised value enables nothing.
func parseNetworkdDHCP(value string) (dhcp4, dhcp6 bool) {
switch strings.ToLower(strings.TrimSpace(value)) {
case "yes", "true", "on", "1", "both":
return true, true
case "ipv4", "v4":
return true, false
case "ipv6", "v6":
return false, true
}
return false, false
}
// formatNetworkdDHCP renders the families back into a DHCP= value, returning
// false when no family is left and the key should be removed rather than
// written as "no". systemd already defaults DHCP= to no.
func formatNetworkdDHCP(dhcp4, dhcp6 bool) (string, bool) {
switch {
case dhcp4 && dhcp6:
return "yes", true
case dhcp4:
return "ipv4", true
case dhcp6:
return "ipv6", true
}
return "", false
}
// setNetworkdDHCP rewrites the [Network] DHCP= key to request a lease for
// exactly the requested families. With neither family enabled the key is
// removed rather than written as "no": systemd already defaults DHCP= to no,
// and a config that never mentioned DHCP should not grow the key.
func setNetworkdDHCP(sec *ini.Section, dhcp4, dhcp6 bool) (err error) {
value, keep := formatNetworkdDHCP(dhcp4, dhcp6)
if !keep {
sec.DeleteKey("DHCP")
return nil
}
if key, kerr := sec.GetKey("DHCP"); kerr == nil {
key.SetValue(value)
return nil
}
_, err = sec.NewKey("DHCP", value)
return err
}
// Verify try parsing networkd configurations.
func newNetworkd(backupRetention int) (n *networkd, err error) {
// Try to parse the networkd configurations. /etc/systemd/network is the
@ -222,6 +272,13 @@ func (nd *networkd) GetInterfaces() (interfaces []*Interface, err error) {
switch sec.Name() {
// IF this is an network section, try to find addresses.
case "Network":
// Read the DHCP client state before the Address lookup below,
// which bails out of this section when no address is set — a
// DHCP-only network has exactly that shape.
if dhcpKey, _ := sec.GetKey("DHCP"); dhcpKey != nil {
i.DHCP4, i.DHCP6 = parseNetworkdDHCP(dhcpKey.String())
}
// Find the addresses in the address key.
addressKey, _ := sec.GetKey("Address")
if addressKey == nil {
@ -516,6 +573,45 @@ func (nd *networkd) SetIfaceAddresses(_ context.Context, iface string, addrs []*
return nil
}
// Set the DHCP client state on an interface.
func (nd *networkd) SetIfaceDHCP(_ context.Context, iface string, dhcp4, dhcp6 bool) (err error) {
for _, n := range nd.Networks {
if n.Name != iface {
continue
}
// Get the network section to modify it.
sec, err := n.Config.GetSection("Network")
if err != nil {
return err
}
if err = setNetworkdDHCP(sec, dhcp4, dhcp6); err != nil {
return err
}
// Save the network.
err = n.Save(nd.configDir, nd.backupRetention)
if err != nil {
return err
}
}
return nil
}
// renewDHCP has systemd-networkd re-read its configuration and reapply it to
// the interface, starting the DHCP client that was just enabled. `networkctl
// reload` picks up the file that was written; `reconfigure` is what actually
// re-runs the interface's configuration, and reload alone would leave the
// change pending until the link next changed state.
func (nd *networkd) renewDHCP(ctx context.Context, iface string) error {
if _, err := runCommand(ctx, "networkctl", "reload"); err != nil {
return err
}
_, err := runCommand(ctx, "networkctl", "reconfigure", iface)
return err
}
// Set static routes to interface.
func (nd *networkd) SetIfaceRoutes(_ context.Context, iface string, routes []*Route) (err error) {
for _, n := range nd.Networks {

83
networkd_test.go
View file

@ -7,26 +7,23 @@ import (
"path/filepath"
"strings"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// Validate the networkd configuration parser/writer functions.
func TestNetworkd(t *testing.T) {
// Setup test file.
tmpDir, err := os.MkdirTemp("", "")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
testDir, err := filepath.Abs("./tests/networkd")
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
resultsDir := filepath.Join(testDir, "results")
// Try to read the test directory for files to copy to our temporary directory.
entries, err := os.ReadDir(testDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
for _, entry := range entries {
if !strings.HasSuffix(entry.Name(), ".network") {
continue
@ -35,28 +32,20 @@ func TestNetworkd(t *testing.T) {
configPath := filepath.Join(testDir, entry.Name())
tmpPath := filepath.Join(tmpDir, entry.Name())
err = fileCopy(configPath, tmpPath)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}
// Setup ifupdown and parse test file.
n, err := readNetworkdConfigDirectory(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err := n.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 1)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Test setting the IP addresses on an interface.
err = n.SetIfaceAddresses(context.Background(), "test_eth0.1556", []*net.IPNet{
@ -73,9 +62,7 @@ func TestNetworkd(t *testing.T) {
Mask: net.CIDRMask(64, 128),
},
}, net.ParseIP("1.2.3.1"), net.ParseIP("fc00::1"))
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = n.SetIfaceRoutes(context.Background(), "test_eth2", []*Route{
@ -96,33 +83,23 @@ func TestNetworkd(t *testing.T) {
Metric: 100,
},
})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify we can re-read configurations.
n, err = readNetworkdConfigDirectory(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = n.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 2)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 1)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Test setting the IP addresses on an interface.
err = n.SetIfaceAddresses(context.Background(), "test_eth0", []*net.IPNet{
@ -131,43 +108,29 @@ func TestNetworkd(t *testing.T) {
Mask: net.CIDRMask(24, 32),
},
}, net.ParseIP("1.2.10.254"), nil)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Test setting routes on an interface.
err = n.SetIfaceRoutes(context.Background(), "test_eth0.1556", []*Route{})
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify we can re-read configurations.
n, err = readNetworkdConfigDirectory(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Get the interfaces state.
interfaces, err = n.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Verify interfaces read from file.
err = testVerifyInterfaces(interfaces, resultsDir, 3)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Read the current file and expected state.
err = testVerifyResults(resultsDir, tmpDir, 2)
if err != nil {
t.Error(err)
}
assert.NoError(t, err)
// Cleanup.
err = os.RemoveAll(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
}

47
options.go
View file

@ -20,6 +20,10 @@ const (
// defaultBackupRetention is how many .bak.* copies are kept per original
// configuration file. Older backups beyond this number are pruned on save.
defaultBackupRetention = 5
// defaultServiceReadyTimeout bounds how long NewConfigurator waits for a
// backend's daemon to come up and finish starting. It only elapses in full
// on a host where the service is registered to run but never arrives.
defaultServiceReadyTimeout = 60 * time.Second
)
// Logger is the minimal logging surface used across the package. It is
@ -72,6 +76,14 @@ type configOptions struct {
// (cPanel/Plesk/InterWorx) and only remove the address from the running
// system and the network-manager configuration files.
skipPanels bool
// allowNoBackends lets NewConfigurator succeed on a Linux host where no
// network configuration backend was detected, where changes would otherwise
// apply to the running system without persisting.
allowNoBackends bool
// serviceReadyTimeout bounds how long backend detection waits for a
// daemon-backed backend (NetworkManager) to become ready; <= 0 does not
// wait at all.
serviceReadyTimeout time.Duration
}
// defaultConfigOptions returns the options used when no Option is supplied.
@ -82,6 +94,7 @@ func defaultConfigOptions() *configOptions {
pingCount: defaultPingCount,
pingTimeout: defaultPingTimeout,
backupRetention: defaultBackupRetention,
serviceReadyTimeout: defaultServiceReadyTimeout,
}
}
@ -193,3 +206,37 @@ func WithSkipPanels(skip bool) Option {
o.skipPanels = skip
}
}
// WithAllowNoBackends lets NewConfigurator return a configurator on a Linux
// host where backend detection found no network configuration backend. By
// default that is an error: netlink would apply an address change to the
// running system, but with nothing to write it to the change would not survive
// a reboot, and the caller would never be told. Enable this when the
// configurator is only used to read state (GetInterfaces), or when the caller
// accepts runtime-only changes.
func WithAllowNoBackends(allowed bool) Option {
return func(o *configOptions) {
o.allowNoBackends = allowed
}
}
// WithServiceReadyTimeout bounds how long NewConfigurator waits for a backend
// whose configuration is made through a daemon rather than a file. Today that
// is NetworkManager: it is configured over D-Bus, so a configurator built
// before the daemon owns its bus name would find no connections to change.
//
// This matters at boot. A host that starts this program from a unit ordered
// alongside NetworkManager, rather than after it, reaches backend detection
// while the daemon is still starting; without the wait it would either fail to
// register the backend at all, or register one that reports an empty interface
// list. The wait ends as soon as the daemon answers and reports it has finished
// starting up, so a host where it is already running pays nothing.
//
// A timeout of zero or less does not wait: detection probes once and proceeds,
// which is the right choice for a caller that has already ordered itself after
// the daemon and would rather fail fast than block.
func WithServiceReadyTimeout(timeout time.Duration) Option {
return func(o *configOptions) {
o.serviceReadyTimeout = timeout
}
}

188
options_test.go
View file

@ -8,6 +8,9 @@ import (
"path/filepath"
"testing"
"time"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// captureLogger records the last formatted message so SetLogger can be
@ -22,57 +25,48 @@ func (c *captureLogger) Println(args ...interface{}) { c.printlnCa
func TestConfigOptionsDefaults(t *testing.T) {
o := newConfigOptions()
if o.testAddress != defaultInternetTestAddress {
t.Errorf("default testAddress = %q, want %q", o.testAddress, defaultInternetTestAddress)
}
if o.skipConnectivityCheck {
t.Error("skipConnectivityCheck = true, want false by default")
}
if o.connectivityTimeout != defaultConnectivityTimeout {
t.Errorf("default connectivityTimeout = %v, want %v", o.connectivityTimeout, defaultConnectivityTimeout)
}
if o.pingCount != defaultPingCount {
t.Errorf("default pingCount = %d, want %d", o.pingCount, defaultPingCount)
}
if o.pingTimeout != defaultPingTimeout {
t.Errorf("default pingTimeout = %v, want %v", o.pingTimeout, defaultPingTimeout)
}
if o.backupRetention != defaultBackupRetention {
t.Errorf("default backupRetention = %d, want %d", o.backupRetention, defaultBackupRetention)
}
if o.allowPrimaryRemoval {
t.Error("allowPrimaryRemoval = true, want false by default")
}
if o.skipPanels {
t.Error("skipPanels = true, want false by default")
}
assert.Equal(t, defaultInternetTestAddress, o.testAddress)
assert.False(t, o.skipConnectivityCheck)
assert.Equal(t, defaultConnectivityTimeout, o.connectivityTimeout)
assert.Equal(t, defaultPingCount, o.pingCount)
assert.Equal(t, defaultPingTimeout, o.pingTimeout)
assert.Equal(t, defaultBackupRetention, o.backupRetention)
assert.Equal(t, defaultServiceReadyTimeout, o.serviceReadyTimeout)
assert.False(t, o.allowPrimaryRemoval)
assert.False(t, o.skipPanels)
assert.False(t, o.allowNoBackends)
}
func TestWithServiceReadyTimeout(t *testing.T) {
o := newConfigOptions(WithServiceReadyTimeout(90 * time.Second))
assert.Equal(t, 90*time.Second, o.serviceReadyTimeout)
// Zero and negative both mean "do not wait", and must be preserved rather
// than falling back to the default the way WithTestAddress("") does.
o = newConfigOptions(WithServiceReadyTimeout(0))
assert.Equal(t, time.Duration(0), o.serviceReadyTimeout)
o = newConfigOptions(WithServiceReadyTimeout(-1))
assert.Equal(t, -1*time.Nanosecond, o.serviceReadyTimeout)
}
func TestWithTestAddress(t *testing.T) {
o := newConfigOptions(WithTestAddress("http://canary.example/health"))
if o.testAddress != "http://canary.example/health" {
t.Errorf("testAddress = %q, want the overridden value", o.testAddress)
}
assert.Equal(t, "http://canary.example/health", o.testAddress)
// An empty address must not clobber the default.
o = newConfigOptions(WithTestAddress(""))
if o.testAddress != defaultInternetTestAddress {
t.Errorf("empty WithTestAddress changed default to %q", o.testAddress)
}
assert.Equal(t, defaultInternetTestAddress, o.testAddress)
}
func TestWithConnectivityCheck(t *testing.T) {
if o := newConfigOptions(WithConnectivityCheck(false)); !o.skipConnectivityCheck {
t.Error("WithConnectivityCheck(false) did not set skipConnectivityCheck")
}
if o := newConfigOptions(WithConnectivityCheck(true)); o.skipConnectivityCheck {
t.Error("WithConnectivityCheck(true) set skipConnectivityCheck")
}
o := newConfigOptions(WithConnectivityCheck(false))
assert.True(t, o.skipConnectivityCheck)
o = newConfigOptions(WithConnectivityCheck(true))
assert.False(t, o.skipConnectivityCheck)
}
func TestWithSkipConnectivityCheck(t *testing.T) {
if o := newConfigOptions(WithSkipConnectivityCheck()); !o.skipConnectivityCheck {
t.Error("WithSkipConnectivityCheck did not set skipConnectivityCheck")
}
o := newConfigOptions(WithSkipConnectivityCheck())
assert.True(t, o.skipConnectivityCheck)
}
func TestSetLogger(t *testing.T) {
@ -81,74 +75,58 @@ func TestSetLogger(t *testing.T) {
cap := &captureLogger{}
SetLogger(cap)
if logger != cap {
t.Fatal("SetLogger did not replace the package logger")
}
require.Equal(t, cap, logger)
logger.Printf("hi %d", 1)
logger.Println("hi")
if cap.printfCalls != 1 || cap.printlnCalls != 1 {
t.Errorf("logger not used: printf=%d println=%d", cap.printfCalls, cap.printlnCalls)
}
assert.Equal(t, 1, cap.printfCalls)
assert.Equal(t, 1, cap.printlnCalls)
// A nil logger must be ignored, leaving the current logger in place.
SetLogger(nil)
if logger != cap {
t.Error("SetLogger(nil) replaced the logger")
}
assert.Equal(t, cap, logger)
}
func TestWithConnectivityTimeout(t *testing.T) {
if o := newConfigOptions(WithConnectivityTimeout(5 * time.Second)); o.connectivityTimeout != 5*time.Second {
t.Errorf("connectivityTimeout = %v, want 5s", o.connectivityTimeout)
}
o := newConfigOptions(WithConnectivityTimeout(5 * time.Second))
assert.Equal(t, 5*time.Second, o.connectivityTimeout)
// Non-positive values must not clobber the default.
if o := newConfigOptions(WithConnectivityTimeout(0)); o.connectivityTimeout != defaultConnectivityTimeout {
t.Errorf("zero WithConnectivityTimeout changed default to %v", o.connectivityTimeout)
}
o = newConfigOptions(WithConnectivityTimeout(0))
assert.Equal(t, defaultConnectivityTimeout, o.connectivityTimeout)
}
func TestWithPingCount(t *testing.T) {
if o := newConfigOptions(WithPingCount(3)); o.pingCount != 3 {
t.Errorf("pingCount = %d, want 3", o.pingCount)
}
o := newConfigOptions(WithPingCount(3))
assert.Equal(t, 3, o.pingCount)
// Non-positive values must not clobber the default.
if o := newConfigOptions(WithPingCount(0)); o.pingCount != defaultPingCount {
t.Errorf("zero WithPingCount changed default to %d", o.pingCount)
}
o = newConfigOptions(WithPingCount(0))
assert.Equal(t, defaultPingCount, o.pingCount)
}
func TestWithPingTimeout(t *testing.T) {
if o := newConfigOptions(WithPingTimeout(30 * time.Second)); o.pingTimeout != 30*time.Second {
t.Errorf("pingTimeout = %v, want 30s", o.pingTimeout)
}
if o := newConfigOptions(WithPingTimeout(0)); o.pingTimeout != defaultPingTimeout {
t.Errorf("zero WithPingTimeout changed default to %v", o.pingTimeout)
}
o := newConfigOptions(WithPingTimeout(30 * time.Second))
assert.Equal(t, 30*time.Second, o.pingTimeout)
o = newConfigOptions(WithPingTimeout(0))
assert.Equal(t, defaultPingTimeout, o.pingTimeout)
}
func TestWithBackupRetention(t *testing.T) {
if o := newConfigOptions(WithBackupRetention(10)); o.backupRetention != 10 {
t.Errorf("backupRetention = %d, want 10", o.backupRetention)
}
o := newConfigOptions(WithBackupRetention(10))
assert.Equal(t, 10, o.backupRetention)
// Zero/negative disables pruning (keeps all backups).
if o := newConfigOptions(WithBackupRetention(0)); o.backupRetention != 0 {
t.Errorf("backupRetention = %d, want 0", o.backupRetention)
}
o = newConfigOptions(WithBackupRetention(0))
assert.Equal(t, 0, o.backupRetention)
}
func TestWithAllowPrimaryRemoval(t *testing.T) {
if o := newConfigOptions(WithAllowPrimaryRemoval(true)); !o.allowPrimaryRemoval {
t.Error("WithAllowPrimaryRemoval(true) did not set allowPrimaryRemoval")
}
o := newConfigOptions(WithAllowPrimaryRemoval(true))
assert.True(t, o.allowPrimaryRemoval)
}
func TestWithSkipPanels(t *testing.T) {
if o := newConfigOptions(WithSkipPanels(true)); !o.skipPanels {
t.Error("WithSkipPanels(true) did not set skipPanels")
}
if o := newConfigOptions(WithSkipPanels(false)); o.skipPanels {
t.Error("WithSkipPanels(false) set skipPanels")
}
o := newConfigOptions(WithSkipPanels(true))
assert.True(t, o.skipPanels)
o = newConfigOptions(WithSkipPanels(false))
assert.False(t, o.skipPanels)
}
// applyIfaceDNS must invoke every backend even when an earlier one fails.
@ -160,22 +138,14 @@ func TestApplyIfaceDNS(t *testing.T) {
{name: "ok", backend: ok},
}
applyIfaceDNS(context.Background(), backends, "eth0", []net.IP{net.ParseIP("8.8.8.8")}, []string{"example.com"})
if failing.dnsCalls != 1 || ok.dnsCalls != 1 {
t.Errorf("dns calls: failing=%d ok=%d, want 1 each", failing.dnsCalls, ok.dnsCalls)
}
assert.Equal(t, 1, failing.dnsCalls)
assert.Equal(t, 1, ok.dnsCalls)
}
func TestIPStrings(t *testing.T) {
got := ipStrings([]net.IP{net.ParseIP("8.8.8.8"), nil, net.ParseIP("2001:4860:4860::8888")})
want := []string{"8.8.8.8", "2001:4860:4860::8888"}
if len(got) != len(want) {
t.Fatalf("ipStrings = %v, want %v", got, want)
}
for i := range want {
if got[i] != want[i] {
t.Errorf("ipStrings[%d] = %q, want %q", i, got[i], want[i])
}
}
require.Equal(t, want, got)
}
// TestNetplanDNS round-trips DNS through the netplan backend: SetIfaceDNS writes
@ -183,29 +153,21 @@ func TestIPStrings(t *testing.T) {
func TestNetplanDNS(t *testing.T) {
tmpDir := t.TempDir()
config := "network:\n version: 2\n ethernets:\n eth0:\n addresses: [192.0.2.10/24]\n"
if err := os.WriteFile(filepath.Join(tmpDir, "01-test.yaml"), []byte(config), 0644); err != nil {
t.Fatal(err)
}
err := os.WriteFile(filepath.Join(tmpDir, "01-test.yaml"), []byte(config), 0644)
require.NoError(t, err)
np, err := readNetplanConfigDirectory(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
servers := []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("2001:4860:4860::8888")}
if err := np.SetIfaceDNS(context.Background(), "eth0", servers, []string{"example.com", "corp.example"}); err != nil {
t.Fatal(err)
}
err = np.SetIfaceDNS(context.Background(), "eth0", servers, []string{"example.com", "corp.example"})
require.NoError(t, err)
// Re-read from disk so we exercise the written config, not in-memory state.
np, err = readNetplanConfigDirectory(tmpDir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
ifaces, err := np.GetInterfaces()
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
var eth0 *Interface
for _, i := range ifaces {
@ -213,13 +175,7 @@ func TestNetplanDNS(t *testing.T) {
eth0 = i
}
}
if eth0 == nil {
t.Fatal("eth0 not found after SetIfaceDNS")
}
if len(eth0.DNS) != 2 || !eth0.DNS[0].Equal(servers[0]) || !eth0.DNS[1].Equal(servers[1]) {
t.Errorf("DNS = %v, want %v", eth0.DNS, servers)
}
if len(eth0.SearchDomains) != 2 || eth0.SearchDomains[0] != "example.com" || eth0.SearchDomains[1] != "corp.example" {
t.Errorf("SearchDomains = %v, want [example.com corp.example]", eth0.SearchDomains)
}
require.NotNil(t, eth0)
assert.True(t, len(eth0.DNS) == 2 && eth0.DNS[0].Equal(servers[0]) && eth0.DNS[1].Equal(servers[1]))
assert.True(t, len(eth0.SearchDomains) == 2 && eth0.SearchDomains[0] == "example.com" && eth0.SearchDomains[1] == "corp.example")
}

78
services.go Normal file
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@ -0,0 +1,78 @@
package netconfig
import (
"context"
"fmt"
"time"
)
// serviceReadyPollInterval is how often waitForServiceReady re-probes. A daemon
// coming up at boot takes seconds, so probing a few times a second costs little
// and returns promptly once it arrives. It is a variable only so tests can wait
// on the loop without sleeping for real.
var serviceReadyPollInterval = 250 * time.Millisecond
// readyProbe reports whether a service is ready to be configured. An error is a
// probe that could not reach the service, which during boot is indistinguishable
// from a service that has not started yet; it is therefore not fatal on its own
// and is only surfaced if the wait runs out.
type readyProbe func() (bool, error)
// waitForServiceReady blocks until probe reports the named service ready, the
// timeout elapses, or ctx is cancelled.
//
// Some backends are configured through a running daemon rather than a file, so
// a configurator constructed before that daemon is up would hold a handle that
// reports nothing and accepts no changes. This program can be started early
// enough in boot to lose that race — from a unit ordered alongside the daemon
// rather than after it — which is what the wait is for.
//
// A timeout of zero or less does not wait: probe runs once and its result is
// reported, so a caller already ordered after the daemon fails fast instead of
// blocking. A service that is already up returns on the first probe and pays no
// delay either way.
func waitForServiceReady(ctx context.Context, name string, timeout time.Duration, probe readyProbe) error {
if timeout > 0 {
var cancel context.CancelFunc
ctx, cancel = context.WithTimeout(ctx, timeout)
defer cancel()
}
ticker := time.NewTicker(serviceReadyPollInterval)
defer ticker.Stop()
waited := false
for {
ready, probeErr := probe()
if ready {
if waited {
logger.Printf("%s: became ready", name)
}
return nil
}
// Not waiting: report why the single probe said no.
if timeout <= 0 {
if probeErr != nil {
return fmt.Errorf("%s is not ready: %w", name, probeErr)
}
return fmt.Errorf("%s is not ready", name)
}
if !waited {
waited = true
logger.Printf("%s: waiting up to %s for the service to become ready", name, timeout)
}
select {
case <-ctx.Done():
// The last probe error explains the wait better than "deadline
// exceeded" does, so prefer it when there was one.
if probeErr != nil {
return fmt.Errorf("timed out waiting for %s: %w", name, probeErr)
}
return fmt.Errorf("timed out waiting for %s: %w", name, ctx.Err())
case <-ticker.C:
}
}
}

267
services_linux.go Normal file
View file

@ -0,0 +1,267 @@
//go:build linux
package netconfig
import (
"context"
"os"
"os/exec"
"path/filepath"
"strings"
dbus "github.com/coreos/go-systemd/dbus"
)
// rcRunlevels are the SysV runlevels a network service can be started in.
// Runlevels 0, 1, and 6 are halt, single-user, and reboot, so nothing is
// registered to start there.
var rcRunlevels = []string{"2", "3", "4", "5"}
// systemdActive reports whether systemd is the running init (/run/systemd/system
// exists), the same marker systemctl uses to decide it can reach the manager.
// It is checked before dialing D-Bus so hosts running Upstart (Ubuntu 14.04) or
// SysVinit (CentOS 5/6) skip a connection that cannot usefully succeed.
func systemdActive() bool {
_, err := os.Stat("/run/systemd/system")
return err == nil
}
// commandExists reports whether name resolves on PATH.
func commandExists(name string) bool {
_, err := exec.LookPath(name)
return err == nil
}
// chkconfigOn reports whether `chkconfig --list name` shows any runlevel on,
// the RHEL-family enablement signal. Returns false when chkconfig is absent.
func chkconfigOn(ctx context.Context, name string) bool {
if !commandExists("chkconfig") {
return false
}
results, err := runCommand(ctx, "chkconfig", "--list", name)
if err != nil {
return false
}
for _, line := range results {
fields := strings.Fields(line)
if len(fields) == 0 || fields[0] != name {
continue
}
for _, f := range fields[1:] {
if _, status, found := strings.Cut(f, ":"); found && status == "on" {
return true
}
}
}
return false
}
// rcRunlevelDirs returns the rcN.d directories under root that a start symlink
// can live in, covering both the Debian/Ubuntu layout (/etc/rcN.d) and the
// Slackware one (/etc/rc.d/rcN.d).
func rcRunlevelDirs(root string) []string {
dirs := make([]string, 0, len(rcRunlevels)*2)
for _, rl := range rcRunlevels {
dirs = append(dirs,
filepath.Join(root, "etc", "rc"+rl+".d"),
filepath.Join(root, "etc", "rc.d", "rc"+rl+".d"),
)
}
return dirs
}
// rcSymlinksOn reports whether an S*name start symlink exists in any rcN.d tree,
// the enablement signal for both update-rc.d (Debian/Ubuntu) and Slackware.
func rcSymlinksOn(name string) bool {
return rcSymlinksOnIn("/", name)
}
// rcSymlinksOnIn is rcSymlinksOn rooted at root, so tests can build a runlevel
// tree in a temporary directory.
func rcSymlinksOnIn(root, name string) bool {
for _, dir := range rcRunlevelDirs(root) {
if matches, _ := filepath.Glob(filepath.Join(dir, "S*"+name)); len(matches) > 0 {
return true
}
}
return false
}
// openrcOn reports whether name is linked into an OpenRC runlevel directory
// (default or boot), the enablement signal created by `rc-update add` on Gentoo.
func openrcOn(name string) bool {
return openrcOnIn("/", name)
}
// openrcOnIn is openrcOn rooted at root, so tests can build a runlevel tree in a
// temporary directory.
func openrcOnIn(root, name string) bool {
for _, rl := range []string{"default", "boot"} {
if _, err := os.Lstat(filepath.Join(root, "etc", "runlevels", rl, name)); err == nil {
return true
}
}
return false
}
// sysvServiceEnabled reports whether name is registered to start at boot under
// a SysV-family init system: chkconfig (RHEL), update-rc.d rcN.d start symlinks
// (Debian/Ubuntu/Slackware), or an OpenRC runlevel (Gentoo). name is the service
// base name without a ".service" suffix. Any one mechanism reporting it on
// counts as enabled.
func sysvServiceEnabled(ctx context.Context, name string) bool {
return chkconfigOn(ctx, name) || rcSymlinksOn(name) || openrcOn(name)
}
// initSystemDiscoverable reports whether this host exposes any init system that
// sysvServiceEnabled or systemd can be asked about. It is false on minimal
// images and containers that have neither systemd nor chkconfig nor runlevel
// directories, where a backend's configuration file is the only evidence
// available and detection has nothing to corroborate it with.
func initSystemDiscoverable() bool {
if systemdActive() || commandExists("chkconfig") {
return true
}
for _, dir := range rcRunlevelDirs("/") {
if _, err := os.Stat(dir); err == nil {
return true
}
}
_, err := os.Stat("/etc/runlevels")
return err == nil
}
// networkServiceUnits are the services backend detection asks systemd about.
// They are collected here so the unit-file lookup can be filtered server side
// to just these names, which is orders of magnitude cheaper than listing every
// unit file on the host. Only these names may be passed to initState.enabled
// and initState.detected; any other name silently skips the systemd answer and
// falls through to the SysV mechanisms.
var networkServiceUnits = []string{"systemd-networkd", "NetworkManager", "network", "networking"}
// initState is a snapshot of what the host's init system reports about its
// units, taken once when the configurator is constructed. Each systemd query
// costs a D-Bus round trip, so the running units and the installed unit files
// are both fetched up front and every per-service question is answered from
// memory afterwards.
type initState struct {
// active holds the unit names ("NetworkManager.service") systemd reports as
// currently running. Empty when systemd could not be queried.
active map[string]bool
// unitFiles maps an installed unit file's base name to its UnitFileState
// ("enabled", "disabled", "generated", ...). A unit that is enabled but was
// never loaded this boot appears here and not in active, which is why both
// are read. Empty when systemd could not be queried.
unitFiles map[string]string
}
// newInitState queries systemd for the host's running units and installed unit
// files. Every step degrades to an empty map rather than an error: a host that
// cannot answer over D-Bus is not broken, it is a host whose services must be
// discovered through the SysV mechanisms instead, which enabled falls back to.
// The queries are bound by ctx so a wedged systemd cannot stall construction.
func newInitState(ctx context.Context) *initState {
s := &initState{
active: make(map[string]bool),
unitFiles: make(map[string]string),
}
// Skip D-Bus entirely when systemd is not the running init. On Ubuntu 14.04
// Upstart is PID 1 and org.freedesktop.systemd1 is served by systemd-shim,
// which accepts the connection but has no ListUnits; on CentOS 5/6 there is
// no systemd1 on the bus at all. Both would otherwise cost a failed dial and
// a failed call before reaching the SysV checks that were always going to
// answer for them.
if !systemdActive() {
return s
}
conn, err := dbus.NewWithContext(ctx)
if err != nil {
logger.Printf("unable to connect to systemd, falling back to init-script detection: %v", err)
return s
}
defer conn.Close()
units, err := conn.ListUnitsContext(ctx)
if err != nil {
logger.Printf("unable to list systemd units, falling back to init-script detection: %v", err)
}
for _, unit := range units {
if unit.ActiveState == "active" {
s.active[unit.Name] = true
}
}
// The unit files report enablement, including for units that are enabled but
// have not been loaded this boot and so never appear in ListUnits.
//
// ListUnitFilesByPatterns filters server side and answers in milliseconds;
// ListUnitFiles walks every unit file on the host and can take seconds on a
// machine with a few hundred of them. Only systemd 230 and later export the
// filtered call, so fall back to the full listing for older systemd (CentOS
// 7 ships 219). Both are read into the same map keyed by unit file name.
patterns := make([]string, 0, len(networkServiceUnits))
for _, name := range networkServiceUnits {
patterns = append(patterns, name+".service")
}
files, err := conn.ListUnitFilesByPatternsContext(ctx, nil, patterns)
if err != nil {
files, err = conn.ListUnitFilesContext(ctx)
}
if err != nil {
logger.Printf("unable to list systemd unit files, falling back to init-script detection: %v", err)
return s
}
for _, uf := range files {
s.unitFiles[filepath.Base(uf.Path)] = uf.Type
}
return s
}
// running reports whether systemd has name's service unit active right now.
func (s *initState) running(name string) bool {
return s.active[name+".service"]
}
// enabled reports whether name is registered to start at boot. systemd's
// UnitFileState is authoritative when it owns the unit outright; a "generated"
// state is not, because systemd-sysv-generator wraps an /etc/init.d script into
// a unit that carries no enablement of its own. RHEL 7 ships network.service
// that way whether or not chkconfig has it on, so a generated unit's real
// enablement is read from its SysV registration, as is any unit systemd has
// never heard of.
func (s *initState) enabled(ctx context.Context, name string) bool {
state, known := s.unitFiles[name+".service"]
if known && state != "generated" {
return state == "enabled" || state == "enabled-runtime"
}
return sysvServiceEnabled(ctx, name)
}
// detected reports whether name's service manages this host's network: either
// it is running now, or it is registered to start at boot. Enablement counts
// independently of the running state because this package writes configuration
// that must survive a reboot. A manager that is enabled but not yet started —
// a host mid-provision, a chroot, an image build, a unit whose start failed —
// still owns the network on the next boot, and systemd's ListUnits does not
// report it at all.
func (s *initState) detected(ctx context.Context, name string) bool {
return s.running(name) || s.enabled(ctx, name)
}
// networkManagerRunning reports whether NetworkManager's daemon left a runtime
// pid file. It is the running-state signal on hosts where systemd cannot be
// queried, and is unioned with the systemd signals rather than replacing them,
// so a partial answer from systemd never hides a manager this can still see.
func networkManagerRunning() bool {
for _, pidFile := range []string{
"/var/run/NetworkManager/NetworkManager.pid",
"/run/NetworkManager/NetworkManager.pid",
} {
if _, err := os.Stat(pidFile); err == nil {
return true
}
}
return false
}

168
services_linux_unit_test.go Normal file
View file

@ -0,0 +1,168 @@
//go:build linux
package netconfig
import (
"context"
"os"
"path/filepath"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// absentService is a service name no host can plausibly have registered, so
// sysvServiceEnabled is guaranteed to answer false for it. It lets the systemd
// branches of initState.enabled be tested without the SysV fallback ever
// masking the result.
const absentService = "netconfig-nonexistent-service"
// A unit file state systemd owns outright is authoritative: only "enabled" and
// "enabled-runtime" count, and the SysV fallback is never consulted.
func TestInitStateEnabledTrustsSystemdUnitFileState(t *testing.T) {
ctx := context.Background()
cases := map[string]bool{
"enabled": true,
"enabled-runtime": true,
"disabled": false,
"static": false,
"masked": false,
}
for state, want := range cases {
s := &initState{
active: map[string]bool{},
unitFiles: map[string]string{absentService + ".service": state},
}
assert.Equal(t, want, s.enabled(ctx, absentService),
"unit file state %q", state)
}
}
// A "generated" unit is a systemd-sysv-generator wrapper around an init.d
// script. It carries no enablement of its own, so it must not be read as
// enabled — RHEL 7 ships network.service that way whether or not chkconfig has
// it on. Enablement has to come from the SysV registration, which for a service
// no host has is absent.
func TestInitStateEnabledDoesNotTrustGeneratedUnits(t *testing.T) {
s := &initState{
active: map[string]bool{},
unitFiles: map[string]string{absentService + ".service": "generated"},
}
assert.False(t, s.enabled(context.Background(), absentService),
"a generated unit with no SysV registration must not read as enabled")
}
// A service systemd has never heard of falls through to the SysV mechanisms
// rather than being reported as disabled.
func TestInitStateEnabledFallsBackForUnknownUnits(t *testing.T) {
s := &initState{active: map[string]bool{}, unitFiles: map[string]string{}}
assert.False(t, s.enabled(context.Background(), absentService))
}
// detected is the union of running and enabled. Enablement must count on its
// own: a manager that is enabled but has not started this boot never appears in
// systemd's ListUnits, yet it owns the network after the next reboot and its
// configuration still has to be written. Equally, a manager that is running but
// disabled owns the network right now.
func TestInitStateDetectedUnionsRunningAndEnabled(t *testing.T) {
ctx := context.Background()
unit := absentService + ".service"
enabledNotRunning := &initState{
active: map[string]bool{},
unitFiles: map[string]string{unit: "enabled"},
}
assert.True(t, enabledNotRunning.detected(ctx, absentService),
"an enabled service that is not running must be detected")
runningNotEnabled := &initState{
active: map[string]bool{unit: true},
unitFiles: map[string]string{unit: "disabled"},
}
assert.True(t, runningNotEnabled.detected(ctx, absentService),
"a running service that is not enabled must be detected")
neither := &initState{
active: map[string]bool{},
unitFiles: map[string]string{unit: "disabled"},
}
assert.False(t, neither.detected(ctx, absentService))
}
// running reads systemd's active-unit set, keyed by the full unit name.
func TestInitStateRunning(t *testing.T) {
s := &initState{
active: map[string]bool{"NetworkManager.service": true},
unitFiles: map[string]string{},
}
assert.True(t, s.running("NetworkManager"))
assert.False(t, s.running("systemd-networkd"))
}
// An S* start symlink in any rcN.d tree marks the service as enabled, in both
// the Debian/Ubuntu (/etc/rcN.d) and Slackware (/etc/rc.d/rcN.d) layouts. A K*
// kill symlink does not.
func TestRcSymlinksOnIn(t *testing.T) {
for _, dir := range []string{"etc/rc2.d", "etc/rc.d/rc3.d", "etc/rc5.d"} {
t.Run(dir, func(t *testing.T) {
root := t.TempDir()
require.NoError(t, os.MkdirAll(filepath.Join(root, dir), 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(root, dir, "S01networking"), nil, 0o644))
assert.True(t, rcSymlinksOnIn(root, "networking"))
assert.False(t, rcSymlinksOnIn(root, "network"),
"S01networking must not match the distinct service %q", "network")
})
}
// A kill symlink means the service is stopped in that runlevel, not started.
root := t.TempDir()
require.NoError(t, os.MkdirAll(filepath.Join(root, "etc/rc2.d"), 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(root, "etc/rc2.d", "K01networking"), nil, 0o644))
assert.False(t, rcSymlinksOnIn(root, "networking"))
// Runlevels 0, 1, and 6 are halt, single-user, and reboot; nothing starts there.
root = t.TempDir()
require.NoError(t, os.MkdirAll(filepath.Join(root, "etc/rc1.d"), 0o755))
require.NoError(t, os.WriteFile(
filepath.Join(root, "etc/rc1.d", "S01networking"), nil, 0o644))
assert.False(t, rcSymlinksOnIn(root, "networking"))
assert.False(t, rcSymlinksOnIn(t.TempDir(), "networking"),
"an empty root has no enabled services")
}
// OpenRC records enablement as a symlink into a runlevel directory.
func TestOpenrcOnIn(t *testing.T) {
for _, rl := range []string{"default", "boot"} {
t.Run(rl, func(t *testing.T) {
root := t.TempDir()
require.NoError(t, os.MkdirAll(filepath.Join(root, "etc/runlevels", rl), 0o755))
require.NoError(t, os.Symlink("/etc/init.d/net.lo",
filepath.Join(root, "etc/runlevels", rl, "net.lo")))
assert.True(t, openrcOnIn(root, "net.lo"))
assert.False(t, openrcOnIn(root, "NetworkManager"))
})
}
// A dangling symlink still marks the service as added to the runlevel, so
// Lstat (not Stat) is what openrcOnIn must use.
root := t.TempDir()
require.NoError(t, os.MkdirAll(filepath.Join(root, "etc/runlevels/default"), 0o755))
require.NoError(t, os.Symlink("/nonexistent",
filepath.Join(root, "etc/runlevels/default/dangling")))
assert.True(t, openrcOnIn(root, "dangling"))
assert.False(t, openrcOnIn(t.TempDir(), "net.lo"))
}
// Every service name detection asks systemd about must be in networkServiceUnits,
// since that list is what the unit-file lookup is filtered by. A name missing
// from it silently loses its systemd answer.
func TestNetworkServiceUnitsCoversDetectedServices(t *testing.T) {
for _, name := range []string{"systemd-networkd", "NetworkManager", "network", "networking"} {
assert.Contains(t, networkServiceUnits, name)
}
}

122
services_unit_test.go Normal file
View file

@ -0,0 +1,122 @@
package netconfig
import (
"context"
"errors"
"testing"
"time"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// fastPolling shrinks the readiness poll interval for the duration of a test,
// so the wait loop can be exercised without sleeping for real.
func fastPolling(t *testing.T) {
t.Helper()
original := serviceReadyPollInterval
serviceReadyPollInterval = time.Millisecond
t.Cleanup(func() { serviceReadyPollInterval = original })
}
// countingProbe reports ready only from the nth call onwards, and records how
// many times it was asked.
func countingProbe(readyOn int, err error) (readyProbe, *int) {
calls := 0
probe := func() (bool, error) {
calls++
if readyOn > 0 && calls >= readyOn {
return true, nil
}
return false, err
}
return probe, &calls
}
func TestWaitForServiceReady(t *testing.T) {
t.Run("a service already up returns on the first probe", func(t *testing.T) {
fastPolling(t)
probe, calls := countingProbe(1, nil)
err := waitForServiceReady(context.Background(), "svc", time.Minute, probe)
require.NoError(t, err)
assert.Equal(t, 1, *calls, "a ready service must not be polled twice")
})
t.Run("waits until the service arrives", func(t *testing.T) {
fastPolling(t)
probe, calls := countingProbe(4, errors.New("no bus yet"))
err := waitForServiceReady(context.Background(), "svc", time.Minute, probe)
require.NoError(t, err)
assert.Equal(t, 4, *calls)
})
t.Run("a probe error while booting is not fatal", func(t *testing.T) {
fastPolling(t)
// The first probes fail with the error a host that has not started
// dbus-daemon yet would give; the service then arrives.
probe, _ := countingProbe(3, errors.New("dial unix /run/dbus: no such file"))
assert.NoError(t, waitForServiceReady(context.Background(), "svc", time.Minute, probe))
})
t.Run("times out and reports the last probe error", func(t *testing.T) {
fastPolling(t)
probeErr := errors.New("name has no owner")
probe, calls := countingProbe(0, probeErr)
err := waitForServiceReady(context.Background(), "NetworkManager", 20*time.Millisecond, probe)
require.Error(t, err)
assert.ErrorIs(t, err, probeErr, "the probe error explains the wait better than a deadline does")
assert.ErrorContains(t, err, "timed out waiting for NetworkManager")
assert.Greater(t, *calls, 1, "the probe must be retried before giving up")
})
t.Run("times out and reports the deadline when the probe never errored", func(t *testing.T) {
fastPolling(t)
probe, _ := countingProbe(0, nil)
err := waitForServiceReady(context.Background(), "svc", 20*time.Millisecond, probe)
require.Error(t, err)
assert.ErrorIs(t, err, context.DeadlineExceeded)
})
t.Run("a cancelled context aborts the wait", func(t *testing.T) {
fastPolling(t)
ctx, cancel := context.WithCancel(context.Background())
cancel()
probe, _ := countingProbe(0, nil)
err := waitForServiceReady(ctx, "svc", time.Minute, probe)
require.Error(t, err)
assert.ErrorIs(t, err, context.Canceled)
})
t.Run("zero timeout probes once and does not wait", func(t *testing.T) {
probe, calls := countingProbe(0, nil)
start := time.Now()
err := waitForServiceReady(context.Background(), "svc", 0, probe)
require.Error(t, err)
assert.ErrorContains(t, err, "svc is not ready")
assert.Equal(t, 1, *calls, "a zero timeout must not retry")
assert.Less(t, time.Since(start), serviceReadyPollInterval, "a zero timeout must not sleep")
})
t.Run("zero timeout surfaces the probe error", func(t *testing.T) {
probeErr := errors.New("name has no owner")
probe, _ := countingProbe(0, probeErr)
err := waitForServiceReady(context.Background(), "svc", 0, probe)
require.Error(t, err)
assert.ErrorIs(t, err, probeErr)
})
t.Run("zero timeout still succeeds when the service is up", func(t *testing.T) {
probe, calls := countingProbe(1, nil)
assert.NoError(t, waitForServiceReady(context.Background(), "svc", 0, probe))
assert.Equal(t, 1, *calls)
})
}

2
tests/networkManager/results/1/test
View file

@ -1,5 +1,5 @@
connection modify main ipv4.method manual ipv4.addresses 1.2.3.4/24,1.2.3.43/24 ipv4.gateway 1.2.3.1
connection modify main ipv6.method manual ipv6.addresses fc00::2/64 ipv6.gateway fc00::1
connection modify main ipv6.method auto ipv6.addresses fc00::2/64 ipv6.gateway fc00::1
connection modify test ipv4.routes 10.253.2.0/24 203.0.113.22 100
connection modify test ipv6.routes abcd:ef12:3455:10::/64 abcd:ef12:3456:10::1 100
connection modify test_eth0 ipv4.dns 8.8.8.8,1.1.1.1 ipv4.dns-search example.com ipv4.ignore-auto-dns yes

6
tests/networkManager/results/2/test
View file

@ -1,10 +1,10 @@
connection modify main ipv4.method manual ipv4.addresses 1.2.3.4/24,1.2.3.43/24 ipv4.gateway 1.2.3.1
connection modify main ipv6.method manual ipv6.addresses fc00::2/64 ipv6.gateway fc00::1
connection modify main ipv6.method auto ipv6.addresses fc00::2/64 ipv6.gateway fc00::1
connection modify test ipv4.routes 10.253.2.0/24 203.0.113.22 100
connection modify test ipv6.routes abcd:ef12:3455:10::/64 abcd:ef12:3456:10::1 100
connection modify test_eth0 ipv4.dns 8.8.8.8,1.1.1.1 ipv4.dns-search example.com ipv4.ignore-auto-dns yes
connection modify test_eth0 ipv6.dns 2001:4860:4860::8888 ipv6.dns-search example.com ipv6.ignore-auto-dns yes
connection modify test_eth0 ipv4.method manual ipv4.addresses 1.2.10.4/24 ipv4.gateway 1.2.10.254
connection modify test_eth0 ipv6.method link-local ipv6.addresses ipv6.gateway
connection modify test_eth0 ipv4.method auto ipv4.addresses 1.2.10.4/24 ipv4.gateway 1.2.10.254
connection modify test_eth0 ipv6.method auto ipv6.addresses ipv6.gateway
connection modify main ipv4.routes
connection modify main ipv6.routes

43
utils.go
View file

@ -111,6 +111,7 @@ func ip2Uint(ip net.IP) uint32 {
// cancelled or expired context terminates it.
func runCommand(ctx context.Context, command string, args ...string) (out []string, err error) {
cmd := exec.CommandContext(ctx, command, args...)
hideCommandWindow(cmd)
// Get output pipes.
var stdout, stderr io.ReadCloser
@ -168,6 +169,48 @@ func runCommand(ctx context.Context, command string, args ...string) (out []stri
return
}
// naturalLess compares two strings the way a person reads them, comparing a run
// of digits by the number it spells rather than character by character, so eth2
// sorts before eth10 and enp0s3 before enp0s10. Digit runs are compared without
// being parsed, so a name carrying a number too large for an integer still
// orders sensibly.
func naturalLess(a, b string) bool {
for a != "" && b != "" {
if isDigit(a[0]) && isDigit(b[0]) {
var aNum, bNum string
aNum, a = leadingDigits(a)
bNum, b = leadingDigits(b)
// Leading zeros change the text but not the value.
aNum = strings.TrimLeft(aNum, "0")
bNum = strings.TrimLeft(bNum, "0")
if len(aNum) != len(bNum) {
return len(aNum) < len(bNum)
}
if aNum != bNum {
return aNum < bNum
}
continue
}
if a[0] != b[0] {
return a[0] < b[0]
}
a, b = a[1:], b[1:]
}
return len(a) < len(b)
}
// isDigit reports whether c is an ASCII digit.
func isDigit(c byte) bool { return c >= '0' && c <= '9' }
// leadingDigits splits s into its leading run of digits and the rest.
func leadingDigits(s string) (digits, rest string) {
i := 0
for i < len(s) && isDigit(s[i]) {
i++
}
return s[:i], s[i:]
}
// ipStrings converts a list of IPs to their string form, skipping nil entries.
func ipStrings(ips []net.IP) []string {
var out []string

9
utils_other.go Normal file
View file

@ -0,0 +1,9 @@
//go:build !windows
package netconfig
import "os/exec"
// hideCommandWindow is a no-op away from Windows, where there is no console
// window for a subprocess to raise.
func hideCommandWindow(*exec.Cmd) {}

275
utils_unit_test.go
View file

@ -6,10 +6,11 @@ import (
"net"
"os"
"path/filepath"
"reflect"
"sort"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"gopkg.in/yaml.v3"
)
@ -19,17 +20,11 @@ func TestIP2UintRoundTrip(t *testing.T) {
cases := []string{"0.0.0.0", "1.2.3.4", "192.168.1.255", "255.255.255.255"}
for _, c := range cases {
ip := net.ParseIP(c)
if ip == nil {
t.Fatalf("could not parse %q", c)
}
require.NotNil(t, ip, "could not parse %q", c)
got := uint2IP(ip2Uint(ip))
if !got.Equal(ip) {
t.Errorf("round trip of %s: got %s", c, got)
}
assert.True(t, got.Equal(ip), "round trip of %s: got %s", c, got)
// uint2IP should produce the canonical four-byte representation.
if len(got) != net.IPv4len {
t.Errorf("uint2IP(%s) length = %d, want %d", c, len(got), net.IPv4len)
}
assert.Equal(t, net.IPv4len, len(got), "uint2IP(%s) length", c)
}
}
@ -38,13 +33,9 @@ func TestIP2UintRoundTrip(t *testing.T) {
func TestIP2UintAcceptsBothRepresentations(t *testing.T) {
ip16 := net.ParseIP("10.20.30.40")
ip4 := ip16.To4()
if ip4 == nil {
t.Fatal("expected an IPv4 address")
}
if ip2Uint(ip16) != ip2Uint(ip4) {
t.Errorf("ip2Uint disagrees for 16-byte (%d) and 4-byte (%d) forms",
ip2Uint(ip16), ip2Uint(ip4))
}
require.NotNil(t, ip4, "expected an IPv4 address")
assert.Equal(t, ip2Uint(ip16), ip2Uint(ip4),
"ip2Uint disagrees for 16-byte and 4-byte forms")
}
func TestAllFF(t *testing.T) {
@ -60,9 +51,7 @@ func TestAllFF(t *testing.T) {
{[]byte{0xff, 0xff, 0xfe}, false},
}
for _, c := range cases {
if got := allFF(c.in); got != c.want {
t.Errorf("allFF(%v) = %v, want %v", c.in, got, c.want)
}
assert.Equal(t, c.want, allFF(c.in), "allFF(%v)", c.in)
}
}
@ -79,14 +68,10 @@ func TestGetBroadcast(t *testing.T) {
}
for _, c := range cases {
_, network, err := net.ParseCIDR(c.cidr)
if err != nil {
t.Fatalf("ParseCIDR(%q): %v", c.cidr, err)
}
require.NoError(t, err, "ParseCIDR(%q)", c.cidr)
got := getBroadcast(network)
want := net.ParseIP(c.want)
if !got.Equal(want) {
t.Errorf("getBroadcast(%s) = %s, want %s", c.cidr, got, c.want)
}
assert.True(t, got.Equal(want), "getBroadcast(%s) = %s, want %s", c.cidr, got, c.want)
}
}
@ -98,243 +83,193 @@ func TestGetBroadcastMixedFamily(t *testing.T) {
Mask: net.CIDRMask(96+24, 128), // /24 expressed as a 16-byte mask.
}
got := getBroadcast(network)
if want := net.ParseIP("192.168.1.255"); !got.Equal(want) {
t.Errorf("getBroadcast mixed family = %s, want %s", got, want)
}
want := net.ParseIP("192.168.1.255")
assert.True(t, got.Equal(want), "getBroadcast mixed family = %s, want %s", got, want)
}
func TestSortableDirEntries(t *testing.T) {
dir := t.TempDir()
names := []string{"zebra", "alpha", "mike", "bravo"}
for _, n := range names {
if err := os.WriteFile(filepath.Join(dir, n), nil, 0o644); err != nil {
t.Fatal(err)
}
require.NoError(t, os.WriteFile(filepath.Join(dir, n), nil, 0o644))
}
entries, err := os.ReadDir(dir)
if err != nil {
t.Fatal(err)
}
require.NoError(t, err)
// Shuffle into a known unsorted order before sorting.
sort.Slice(entries, func(i, j int) bool {
return entries[i].Name() > entries[j].Name()
})
sortable := sortableDirEntries(entries)
if sortable.Len() != len(names) {
t.Errorf("Len() = %d, want %d", sortable.Len(), len(names))
}
assert.Equal(t, len(names), sortable.Len(), "Len()")
sort.Sort(sortable)
want := []string{"alpha", "bravo", "mike", "zebra"}
for i, w := range want {
if entries[i].Name() != w {
t.Errorf("sorted[%d] = %s, want %s", i, entries[i].Name(), w)
}
assert.Equal(t, w, entries[i].Name(), "sorted[%d]", i)
}
}
func TestIntStringYAML(t *testing.T) {
t.Run("int", func(t *testing.T) {
var v intString
if err := yaml.Unmarshal([]byte("42\n"), &v); err != nil {
t.Fatal(err)
}
if v.Int == nil || *v.Int != 42 {
t.Fatalf("Int = %v, want 42", v.Int)
}
if v.String != nil {
t.Errorf("String should be nil, got %v", *v.String)
}
require.NoError(t, yaml.Unmarshal([]byte("42\n"), &v))
require.NotNil(t, v.Int, "Int = %v, want 42", v.Int)
assert.Equal(t, 42, *v.Int)
assert.Nil(t, v.String, "String should be nil")
out, err := yaml.Marshal(v)
if err != nil {
t.Fatal(err)
}
if got := string(out); got != "42\n" {
t.Errorf("marshal = %q, want %q", got, "42\n")
}
require.NoError(t, err)
assert.Equal(t, "42\n", string(out), "marshal")
})
t.Run("string", func(t *testing.T) {
var v intString
if err := yaml.Unmarshal([]byte("auto\n"), &v); err != nil {
t.Fatal(err)
}
if v.String == nil || *v.String != "auto" {
t.Fatalf("String = %v, want auto", v.String)
}
if v.Int != nil {
t.Errorf("Int should be nil, got %v", *v.Int)
}
require.NoError(t, yaml.Unmarshal([]byte("auto\n"), &v))
require.NotNil(t, v.String, "String = %v, want auto", v.String)
assert.Equal(t, "auto", *v.String)
assert.Nil(t, v.Int, "Int should be nil")
out, err := yaml.Marshal(v)
if err != nil {
t.Fatal(err)
}
if got := string(out); got != "auto\n" {
t.Errorf("marshal = %q, want %q", got, "auto\n")
}
require.NoError(t, err)
assert.Equal(t, "auto\n", string(out), "marshal")
})
t.Run("empty marshals to null", func(t *testing.T) {
out, err := yaml.Marshal(intString{})
if err != nil {
t.Fatal(err)
}
if got := string(out); got != "null\n" {
t.Errorf("marshal of empty = %q, want %q", got, "null\n")
}
require.NoError(t, err)
assert.Equal(t, "null\n", string(out), "marshal of empty")
})
}
func TestIntStringJSON(t *testing.T) {
t.Run("int", func(t *testing.T) {
var v intString
if err := json.Unmarshal([]byte("42"), &v); err != nil {
t.Fatal(err)
}
if v.Int == nil || *v.Int != 42 {
t.Fatalf("Int = %v, want 42", v.Int)
}
require.NoError(t, json.Unmarshal([]byte("42"), &v))
require.NotNil(t, v.Int, "Int = %v, want 42", v.Int)
assert.Equal(t, 42, *v.Int)
out, err := json.Marshal(v)
if err != nil {
t.Fatal(err)
}
if got := string(out); got != "42" {
t.Errorf("marshal = %q, want %q", got, "42")
}
require.NoError(t, err)
assert.Equal(t, "42", string(out), "marshal")
})
t.Run("string", func(t *testing.T) {
var v intString
if err := json.Unmarshal([]byte(`"auto"`), &v); err != nil {
t.Fatal(err)
}
if v.String == nil || *v.String != "auto" {
t.Fatalf("String = %v, want auto", v.String)
}
require.NoError(t, json.Unmarshal([]byte(`"auto"`), &v))
require.NotNil(t, v.String, "String = %v, want auto", v.String)
assert.Equal(t, "auto", *v.String)
out, err := json.Marshal(v)
if err != nil {
t.Fatal(err)
}
if got := string(out); got != `"auto"` {
t.Errorf("marshal = %q, want %q", got, `"auto"`)
}
require.NoError(t, err)
assert.Equal(t, `"auto"`, string(out), "marshal")
})
t.Run("invalid", func(t *testing.T) {
var v intString
if err := json.Unmarshal([]byte("{}"), &v); err == nil {
t.Error("expected error for object input, got nil")
}
err := json.Unmarshal([]byte("{}"), &v)
assert.Error(t, err, "expected error for object input, got nil")
})
}
func TestRunCommand(t *testing.T) {
t.Run("stdout", func(t *testing.T) {
out, err := runCommand(context.Background(), "printf", "line1\nline2\n")
if err != nil {
t.Fatalf("unexpected error: %v", err)
}
require.NoError(t, err, "unexpected error")
want := []string{"line1", "line2"}
if !reflect.DeepEqual(out, want) {
t.Errorf("out = %v, want %v", out, want)
}
assert.Equal(t, want, out, "out")
})
t.Run("nonzero exit", func(t *testing.T) {
_, err := runCommand(context.Background(), "false")
if err == nil {
t.Error("expected error for failing command, got nil")
}
assert.Error(t, err, "expected error for failing command, got nil")
})
t.Run("missing binary", func(t *testing.T) {
_, err := runCommand(context.Background(), "this-binary-should-not-exist-12345")
if err == nil {
t.Error("expected error for missing binary, got nil")
}
assert.Error(t, err, "expected error for missing binary, got nil")
})
}
func TestTestInternet(t *testing.T) {
if !testInternet(context.Background(), "test_success", 0) {
t.Error("test_success sentinel should report success")
}
if testInternet(context.Background(), "test_fail", 0) {
t.Error("test_fail sentinel should report failure")
}
assert.True(t, testInternet(context.Background(), "test_success", 0),
"test_success sentinel should report success")
assert.False(t, testInternet(context.Background(), "test_fail", 0),
"test_fail sentinel should report failure")
}
func TestFileCopyAndMove(t *testing.T) {
dir := t.TempDir()
src := filepath.Join(dir, "src.txt")
content := []byte("hello world\n")
if err := os.WriteFile(src, content, 0o640); err != nil {
t.Fatal(err)
}
require.NoError(t, os.WriteFile(src, content, 0o640))
t.Run("fileCopy preserves contents and mode", func(t *testing.T) {
dst := filepath.Join(dir, "copy.txt")
if err := fileCopy(src, dst); err != nil {
t.Fatal(err)
}
require.NoError(t, fileCopy(src, dst))
got, err := os.ReadFile(dst)
if err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(got, content) {
t.Errorf("copied contents = %q, want %q", got, content)
}
require.NoError(t, err)
assert.Equal(t, content, got, "copied contents")
fi, err := os.Stat(dst)
if err != nil {
t.Fatal(err)
}
if fi.Mode().Perm() != 0o640 {
t.Errorf("copied mode = %v, want 0640", fi.Mode().Perm())
}
require.NoError(t, err)
assert.Equal(t, os.FileMode(0o640), fi.Mode().Perm(), "copied mode")
})
t.Run("fileCopy missing source errors", func(t *testing.T) {
if err := fileCopy(filepath.Join(dir, "nope"), filepath.Join(dir, "out")); err == nil {
t.Error("expected error for missing source")
}
err := fileCopy(filepath.Join(dir, "nope"), filepath.Join(dir, "out"))
assert.Error(t, err, "expected error for missing source")
})
t.Run("fileMoveCopy removes source", func(t *testing.T) {
moveSrc := filepath.Join(dir, "movesrc.txt")
if err := os.WriteFile(moveSrc, content, 0o644); err != nil {
t.Fatal(err)
}
require.NoError(t, os.WriteFile(moveSrc, content, 0o644))
dst := filepath.Join(dir, "moved.txt")
if err := fileMoveCopy(moveSrc, dst); err != nil {
t.Fatal(err)
}
if _, err := os.Stat(moveSrc); !os.IsNotExist(err) {
t.Errorf("source should be gone, stat err = %v", err)
}
require.NoError(t, fileMoveCopy(moveSrc, dst))
_, err := os.Stat(moveSrc)
assert.True(t, os.IsNotExist(err), "source should be gone, stat err = %v", err)
got, err := os.ReadFile(dst)
if err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(got, content) {
t.Errorf("moved contents = %q, want %q", got, content)
}
require.NoError(t, err)
assert.Equal(t, content, got, "moved contents")
})
t.Run("fileMove same device renames", func(t *testing.T) {
moveSrc := filepath.Join(dir, "rename-src.txt")
if err := os.WriteFile(moveSrc, content, 0o644); err != nil {
t.Fatal(err)
}
require.NoError(t, os.WriteFile(moveSrc, content, 0o644))
dst := filepath.Join(dir, "renamed.txt")
if err := fileMove(moveSrc, dst); err != nil {
t.Fatal(err)
}
if _, err := os.Stat(moveSrc); !os.IsNotExist(err) {
t.Errorf("source should be gone after move, stat err = %v", err)
}
if _, err := os.Stat(dst); err != nil {
t.Errorf("destination missing after move: %v", err)
}
require.NoError(t, fileMove(moveSrc, dst))
_, err := os.Stat(moveSrc)
assert.True(t, os.IsNotExist(err), "source should be gone after move, stat err = %v", err)
_, err = os.Stat(dst)
assert.NoError(t, err, "destination missing after move")
})
}
func TestNaturalLess(t *testing.T) {
cases := []struct {
a, b string
want bool
why string
}{
{"eth2", "eth10", true, "digit runs compare by value, not character"},
{"eth10", "eth2", false, "reversed"},
{"eth0", "eth1", true, "same width digits"},
{"enp0s3", "enp0s10", true, "embedded digit runs"},
{"eth0", "eth0", false, "equal strings are not less"},
{"eth", "eth0", true, "a prefix sorts before what extends it"},
{"eth0", "eth", false, "reversed prefix"},
{"eth007", "eth7", false, "leading zeros do not change the value"},
{"eth7", "eth007", false, "reversed equal values"},
{"eth1", "wlan0", true, "letters compare by byte"},
{"9", "10", true, "bare numbers"},
{"eth99999999999999999999", "eth999999999999999999999", true, "digit runs too long to parse"},
}
for _, c := range cases {
assert.Equal(t, c.want, naturalLess(c.a, c.b), "naturalLess(%q, %q): %s", c.a, c.b, c.why)
}
}
func TestLeadingDigits(t *testing.T) {
digits, rest := leadingDigits("10s3")
assert.Equal(t, "10", digits)
assert.Equal(t, "s3", rest)
digits, rest = leadingDigits("eth0")
assert.Empty(t, digits)
assert.Equal(t, "eth0", rest)
}

13
utils_windows.go Normal file
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package netconfig
import (
"os/exec"
"syscall"
)
// hideCommandWindow keeps a subprocess from flashing a console window on a
// desktop session. Every command this package runs on Windows (netsh, ipconfig)
// is a console program, and without this each one briefly steals focus.
func hideCommandWindow(cmd *exec.Cmd) {
cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
}