forked from cerc-io/ipld-eth-server
46 lines
1.2 KiB
Go
46 lines
1.2 KiB
Go
// Copyright (c) 2016 Arista Networks, Inc.
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// Use of this source code is governed by the Apache License 2.0
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// that can be found in the COPYING file.
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// Package netns provides a utility function that allows a user to
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// perform actions in a different network namespace
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package netns
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import (
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"fmt"
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)
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const (
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netNsRunDir = "/var/run/netns/"
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selfNsFile = "/proc/self/ns/net"
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)
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// Callback is a function that gets called in a given network namespace.
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// The user needs to check any errors from any calls inside this function.
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type Callback func() error
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// File descriptor interface so we can mock for testing
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type handle interface {
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close() error
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fd() int
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}
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// The file descriptor associated with a network namespace
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type nsHandle int
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// setNsByName wraps setNs, allowing specification of the network namespace by name.
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// It returns the file descriptor mapped to the given network namespace.
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func setNsByName(nsName string) error {
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netPath := netNsRunDir + nsName
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handle, err := getNs(netPath)
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if err != nil {
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return fmt.Errorf("Failed to getNs: %s", err)
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}
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err = setNs(handle)
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handle.close()
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if err != nil {
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return fmt.Errorf("Failed to setNs: %s", err)
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}
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return nil
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}
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