feat: add udp proxy mode

This commit is contained in:
Garionion 2023-03-05 13:39:06 +01:00
parent 9c6d945cf3
commit 2bc35c1a26
3 changed files with 95 additions and 13 deletions

7
go.mod
View file

@ -3,9 +3,12 @@ module tcp-proxy
go 1.19 go 1.19
require ( require (
github.com/integrii/flaggy v1.5.2 // indirect github.com/integrii/flaggy v1.5.2
github.com/rs/zerolog v1.29.0
)
require (
github.com/mattn/go-colorable v0.1.13 // indirect github.com/mattn/go-colorable v0.1.13 // indirect
github.com/mattn/go-isatty v0.0.17 // indirect github.com/mattn/go-isatty v0.0.17 // indirect
github.com/rs/zerolog v1.29.0 // indirect
golang.org/x/sys v0.4.0 // indirect golang.org/x/sys v0.4.0 // indirect
) )

1
go.sum
View file

@ -1,5 +1,6 @@
github.com/coreos/go-systemd/v22 v22.3.3-0.20220203105225-a9a7ef127534/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc= github.com/coreos/go-systemd/v22 v22.3.3-0.20220203105225-a9a7ef127534/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA= github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
github.com/google/go-cmp v0.5.6 h1:BKbKCqvP6I+rmFHt06ZmyQtvB8xAkWdhFyr0ZUNZcxQ=
github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE= github.com/google/go-cmp v0.5.6/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
github.com/integrii/flaggy v1.5.2 h1:bWV20MQEngo4hWhno3i5Z9ISPxLPKj9NOGNwTWb/8IQ= github.com/integrii/flaggy v1.5.2 h1:bWV20MQEngo4hWhno3i5Z9ISPxLPKj9NOGNwTWb/8IQ=
github.com/integrii/flaggy v1.5.2/go.mod h1:dO13u7SYuhk910nayCJ+s1DeAAGC1THCMj1uSFmwtQ8= github.com/integrii/flaggy v1.5.2/go.mod h1:dO13u7SYuhk910nayCJ+s1DeAAGC1THCMj1uSFmwtQ8=

100
main.go
View file

@ -17,35 +17,113 @@ func main() {
var ( var (
listenAddr = ":8000" listenAddr = ":8000"
forwardAddr string forwardAddr string
mode = "tcp"
) )
flaggy.String(&listenAddr, "l", "listen", "Address to listen on") flaggy.String(&listenAddr, "l", "listen", "Address to listen on")
flaggy.String(&forwardAddr, "f", "forward", "Address to forward to") flaggy.String(&forwardAddr, "f", "forward", "Address to forward to")
flaggy.String(&mode, "m", "mode", "Mode to use (tcp, udp)")
flaggy.Parse() flaggy.Parse()
if forwardAddr == "" { if forwardAddr == "" {
log.Fatal().Msg("Forward address is required") log.Fatal().Msg("Forward address is required")
} }
ln, err := net.Listen("tcp", listenAddr) if mode == "tcp" {
if err != nil { tcpListen(listenAddr, forwardAddr)
log.Panic().Err(err).Msg("Failed to listen") } else if mode == "udp" {
udpListen(listenAddr, forwardAddr)
} else {
log.Fatal().Msg("Invalid mode")
} }
defer ln.Close()
log.Info().Str("Listen Address", listenAddr).Msg("Listening") }
func tcpListen(listenAddr, forwardAddr string) {
var (
ln net.Listener
err error
)
if ln, err = net.Listen("tcp", listenAddr); err != nil {
log.Panic().Err(err).Str("Mode", "TCP").Msg("Failed to listen")
}
log.Info().Str("Mode", "TCP").Str("Listen Address", listenAddr).Msg("Listening")
defer ln.Close()
for { for {
conn, err := ln.Accept() conn, err := ln.Accept()
if err != nil { if err != nil {
log.Err(err).Msg("Failed to accept connection") log.Err(err).Str("Mode", "TCP").Msg("Failed to accept connection")
continue continue
} }
log.Info().Str("Incoming Address", conn.RemoteAddr().String()).Msg("Connection accepted") log.Info().Str("Mode", "TCP").Str("Incoming Address", conn.RemoteAddr().String()).Msg("Connection accepted")
go handleConnection(conn, forwardAddr) go handleConnection(conn, forwardAddr)
} }
}
func udpListen(la, forwardAddr string) {
// Listen for incoming UDP packets on port 3000
listenAddr, err := net.ResolveUDPAddr("udp", la)
if err != nil {
log.Err(err).Str("Mode", "UDP").Msg("Failed to resolve UDP listen address")
return
}
listener, err := net.ListenUDP("udp", listenAddr)
if err != nil {
log.Err(err).Str("Mode", "UDP").Msg("Failed to listen on UDP port")
return
}
defer listener.Close()
log.Info().Str("Mode", "UDP").Str("Listen Address", listenAddr.String()).Msg("Listening")
// Forward incoming UDP packets to another host and port
remoteAddr, err := net.ResolveUDPAddr("udp", forwardAddr)
if err != nil {
log.Err(err).Str("Mode", "UDP").Msg("Failed to resolve remote address")
return
}
var (
callerAddr *net.UDPAddr
sendAddr *net.UDPAddr
)
buf := make([]byte, 2048)
for {
n, addr, err := listener.ReadFromUDP(buf)
if err != nil {
log.Err(err).Str("Mode", "UDP").Msg("Failed to read from UDP connection")
continue
}
if callerAddr == nil {
callerAddr = addr
}
if addr.String() == remoteAddr.String() {
sendAddr = callerAddr
} else {
sendAddr = remoteAddr
callerAddr = addr
}
//log.Info().Str("Mode", "UDP").Str("Incoming Address", addr.String()).Str("Forward Address", sendAddr.String()).Msg("Packet received")
_, err = listener.WriteToUDP(buf[:n], sendAddr)
if err != nil {
log.Err(err).Str("Mode", "udp").Msg("Failed to write to UDP connection")
continue
}
}
} }
func handleConnection(conn net.Conn, forwardAddr string) { func handleConnection(conn net.Conn, forwardAddr string) {
@ -53,7 +131,7 @@ func handleConnection(conn net.Conn, forwardAddr string) {
fwrd, err := net.Dial("tcp", forwardAddr) fwrd, err := net.Dial("tcp", forwardAddr)
if err != nil { if err != nil {
log.Err(err).Msg("Failed to connect to forward address") log.Err(err).Str("Mode", "TCP").Msg("Failed to connect to forward address")
return return
} }
@ -67,7 +145,7 @@ func handleConnection(conn net.Conn, forwardAddr string) {
_, err := io.Copy(fwrd, conn) _, err := io.Copy(fwrd, conn)
if err != nil { if err != nil {
log.Err(err).Msg("Failed to copy from connection to forward address") log.Err(err).Str("Mode", "TCP").Msg("Failed to copy from connection to forward address")
} }
}() }()
@ -77,10 +155,10 @@ func handleConnection(conn net.Conn, forwardAddr string) {
_, err := io.Copy(conn, fwrd) _, err := io.Copy(conn, fwrd)
if err != nil { if err != nil {
log.Err(err).Msg("Failed to copy from forward address to connection") log.Err(err).Str("Mode", "TCP").Msg("Failed to copy from forward address to connection")
} }
}() }()
wg.Wait() wg.Wait()
log.Info().Str("Incoming Address", conn.RemoteAddr().String()).Msg("Connection closed") log.Info().Str("Mode", "TCP").Str("Incoming Address", conn.RemoteAddr().String()).Msg("Connection closed")
} }