Xray-core/transport/internet/system_listener.go
2023-04-23 19:32:07 +08:00

127 lines
3.6 KiB
Go

package internet
import (
"context"
"os"
"runtime"
"strconv"
"strings"
"syscall"
"time"
"github.com/pires/go-proxyproto"
"github.com/sagernet/sing/common/control"
"github.com/xtls/xray-core/common/net"
"github.com/xtls/xray-core/common/session"
)
var effectiveListener = DefaultListener{}
type DefaultListener struct {
controllers []control.Func
}
func getControlFunc(ctx context.Context, sockopt *SocketConfig, controllers []control.Func) func(network, address string, c syscall.RawConn) error {
return func(network, address string, c syscall.RawConn) error {
return c.Control(func(fd uintptr) {
for _, controller := range controllers {
if err := controller(network, address, c); err != nil {
newError("failed to apply external controller").Base(err).WriteToLog(session.ExportIDToError(ctx))
}
}
if sockopt != nil {
if err := applyInboundSocketOptions(network, fd, sockopt); err != nil {
newError("failed to apply socket options to incoming connection").Base(err).WriteToLog(session.ExportIDToError(ctx))
}
}
setReusePort(fd)
})
}
}
func (dl *DefaultListener) Listen(ctx context.Context, addr net.Addr, sockopt *SocketConfig) (l net.Listener, err error) {
var lc net.ListenConfig
var network, address string
switch addr := addr.(type) {
case *net.TCPAddr:
network = addr.Network()
address = addr.String()
lc.Control = getControlFunc(ctx, sockopt, dl.controllers)
if sockopt != nil && (sockopt.TcpKeepAliveInterval != 0 || sockopt.TcpKeepAliveIdle != 0) {
lc.KeepAlive = time.Duration(-1)
}
case *net.UnixAddr:
lc.Control = nil
network = addr.Network()
address = addr.Name
if s := strings.Split(address, ","); len(s) == 2 {
address = s[0]
perm, perr := strconv.ParseUint(s[1], 8, 32)
if perr != nil {
return nil, newError("failed to parse permission: " + s[1]).Base(perr)
}
defer func(file string, permission os.FileMode) {
if err == nil {
cerr := os.Chmod(address, permission)
if cerr != nil {
err = newError("failed to set permission for " + file).Base(cerr)
}
}
}(address, os.FileMode(perm))
}
if (runtime.GOOS == "linux" || runtime.GOOS == "android") && address[0] == '@' {
// linux abstract unix domain socket is lockfree
if len(address) > 1 && address[1] == '@' {
// but may need padding to work with haproxy
fullAddr := make([]byte, len(syscall.RawSockaddrUnix{}.Path))
copy(fullAddr, address[1:])
address = string(fullAddr)
}
} else {
// normal unix domain socket needs lock
locker := &FileLocker{
path: address + ".lock",
}
err := locker.Acquire()
if err != nil {
return nil, err
}
ctx = context.WithValue(ctx, address, locker)
}
}
l, err = lc.Listen(ctx, network, address)
if sockopt != nil && sockopt.AcceptProxyProtocol {
policyFunc := func(upstream net.Addr) (proxyproto.Policy, error) { return proxyproto.REQUIRE, nil }
l = &proxyproto.Listener{Listener: l, Policy: policyFunc}
}
return l, err
}
func (dl *DefaultListener) ListenPacket(ctx context.Context, addr net.Addr, sockopt *SocketConfig) (net.PacketConn, error) {
var lc net.ListenConfig
lc.Control = getControlFunc(ctx, sockopt, dl.controllers)
return lc.ListenPacket(ctx, addr.Network(), addr.String())
}
// RegisterListenerController adds a controller to the effective system listener.
// The controller can be used to operate on file descriptors before they are put into use.
//
// xray:api:beta
func RegisterListenerController(controller control.Func) error {
if controller == nil {
return newError("nil listener controller")
}
effectiveListener.controllers = append(effectiveListener.controllers, controller)
return nil
}