mirror of
https://github.com/fatedier/frp.git
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76 lines
1.8 KiB
Go
76 lines
1.8 KiB
Go
// Copyright 2025 The frp Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package vnet
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import (
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"io"
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"golang.zx2c4.com/wireguard/tun"
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)
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type tunDevice struct {
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dev tun.Device
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}
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func (d *tunDevice) Read(p []byte) (int, error) {
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// Wireguard's TUN implementation expects a 4-byte offset before the data
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// Make a larger buffer with room for the offset
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buf := make([]byte, len(p)+4)
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// Create sizes array for wireguard to populate
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sz := make([]int, 1)
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// Call wireguard's Read with offset=4
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n, err := d.dev.Read([][]byte{buf}, sz, 4)
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if err != nil {
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return 0, err
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}
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if n == 0 {
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return 0, io.EOF
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}
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// Copy the actual data (excluding the 4-byte offset) to the output buffer
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dataSize := sz[0]
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if dataSize > len(p) {
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dataSize = len(p)
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}
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copy(p, buf[4:4+dataSize])
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return dataSize, nil
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}
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func (d *tunDevice) Write(p []byte) (int, error) {
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buf := make([]byte, len(p)+4)
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copy(buf[4:], p)
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return d.dev.Write([][]byte{buf}, 4)
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}
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func (d *tunDevice) Close() error {
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return d.dev.Close()
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}
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func createTunDevice(adviceName string, mtu int) (io.ReadWriteCloser, string, error) {
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ifce, err := tun.CreateTUN(adviceName, mtu)
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if err != nil {
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return nil, "", err
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}
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name, err := ifce.Name()
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if err != nil {
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return nil, "", err
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}
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return &tunDevice{dev: ifce}, name, nil
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}
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