43 lines
992 B
Go
43 lines
992 B
Go
// Copyright (c) 2026, Pim van Pelt <pim@ipng.ch>
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package prober
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import (
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"fmt"
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"runtime"
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"github.com/vishvananda/netns"
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)
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// inNetns runs fn while the current OS thread is switched into the named
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// network namespace. The thread is locked for the duration so the switch is safe.
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// The original netns is restored before returning.
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// If nsName is empty, fn is run in the current namespace without any switching.
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func inNetns(nsName string, fn func() error) error {
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if nsName == "" {
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return fn()
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}
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runtime.LockOSThread()
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defer runtime.UnlockOSThread()
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origNs, err := netns.Get()
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if err != nil {
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return fmt.Errorf("get current netns: %w", err)
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}
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defer origNs.Close()
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defer netns.Set(origNs) //nolint:errcheck
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targetNs, err := netns.GetFromName(nsName)
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if err != nil {
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return fmt.Errorf("get netns %q: %w", nsName, err)
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}
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defer targetNs.Close()
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if err := netns.Set(targetNs); err != nil {
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return fmt.Errorf("enter netns %q: %w", nsName, err)
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}
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return fn()
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}
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