Whitebox/go-sshd
1
0
Fork 0
Code Issues Pull requests Releases Wiki Activity

Add flag parsing

Browse source
This commit is contained in:
Merlijn B. W. Wajer 2017-03-04 22:59:16 +01:00
parent bbbc8fad88
commit a89882af11
1 changed files with 23 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

25
sshd.go
View file

@ -9,6 +9,7 @@ package main
// * https://github.com/tg123/sshpiper/commit/9db468b52dfc2cbe936efb7bef0fd5b88e0c1649 // * https://github.com/tg123/sshpiper/commit/9db468b52dfc2cbe936efb7bef0fd5b88e0c1649
import ( import (
"flag"
"fmt" "fmt"
"io" "io"
"io/ioutil" "io/ioutil"
@ -23,9 +24,15 @@ import (
var ( var (
authorisedKeys map[string]string authorisedKeys map[string]string
hostkey = flag.String("hostkey", "id_rsa", "Server host key to load")
authorisedkeys = flag.String("authorisedkeys", "authorized_keys", "Authorised keys")
verbose = flag.Bool("verbose", false, "Enable verbose mode")
) )
func main() { func main() {
flag.Parse()
config := &ssh.ServerConfig{ config := &ssh.ServerConfig{
PublicKeyCallback: func(conn ssh.ConnMetadata, key ssh.PublicKey) (*ssh.Permissions, error) { PublicKeyCallback: func(conn ssh.ConnMetadata, key ssh.PublicKey) (*ssh.Permissions, error) {
if ports, found := authorisedKeys[string(key.Marshal())]; found { if ports, found := authorisedKeys[string(key.Marshal())]; found {
@ -38,8 +45,7 @@ func main() {
}, },
} }
privateBytes, err := ioutil.ReadFile("id_ed25519") privateBytes, err := ioutil.ReadFile(*hostkey)
//privateBytes, err := ioutil.ReadFile("id_rsa")
if err != nil { if err != nil {
log.Fatal("Failed to load private key (./id_rsa)") log.Fatal("Failed to load private key (./id_rsa)")
} }
@ -50,7 +56,7 @@ func main() {
} }
config.AddHostKey(private) config.AddHostKey(private)
loadKeys() loadAuthorisedKeys(*authorisedkeys)
listener, err := net.Listen("tcp", "0.0.0.0:2200") listener, err := net.Listen("tcp", "0.0.0.0:2200")
if err != nil { if err != nil {
@ -74,7 +80,9 @@ func main() {
allowedPorts := sshConn.Permissions.CriticalOptions["ports"] allowedPorts := sshConn.Permissions.CriticalOptions["ports"]
if *verbose {
log.Printf("Connection from %s (%s). Allowed ports: %s", sshConn.RemoteAddr(), sshConn.ClientVersion(), allowedPorts) log.Printf("Connection from %s (%s). Allowed ports: %s", sshConn.RemoteAddr(), sshConn.ClientVersion(), allowedPorts)
}
// Parsing a second time should not error // Parsing a second time should not error
ports, _ := parsePorts(allowedPorts) ports, _ := parsePorts(allowedPorts)
@ -101,7 +109,9 @@ type directTCPPayload struct {
} }
func handleChannel(newChannel ssh.NewChannel, ports []uint32) { func handleChannel(newChannel ssh.NewChannel, ports []uint32) {
if *verbose {
log.Println("Channel type:", newChannel.ChannelType()) log.Println("Channel type:", newChannel.ChannelType())
}
if t := newChannel.ChannelType(); t != "direct-tcpip" { if t := newChannel.ChannelType(); t != "direct-tcpip" {
newChannel.Reject(ssh.Prohibited, fmt.Sprintf("Only \"direct-tcpip\" is accepted")) newChannel.Reject(ssh.Prohibited, fmt.Sprintf("Only \"direct-tcpip\" is accepted"))
return return
@ -115,7 +125,6 @@ func handleChannel(newChannel ssh.NewChannel, ports []uint32) {
return return
} }
//log.Println("Got payload: %v", payload)
if payload.Addr != "localhost" { if payload.Addr != "localhost" {
newChannel.Reject(ssh.Prohibited, fmt.Sprintf("Bad addr")) newChannel.Reject(ssh.Prohibited, fmt.Sprintf("Bad addr"))
return return
@ -144,7 +153,9 @@ func handleChannel(newChannel ssh.NewChannel, ports []uint32) {
} }
addr := fmt.Sprintf("%s:%d", payload.Addr, payload.Port) addr := fmt.Sprintf("%s:%d", payload.Addr, payload.Port)
if *verbose {
log.Println("Going to dial:", addr) log.Println("Going to dial:", addr)
}
rconn, err := net.Dial("tcp", addr) rconn, err := net.Dial("tcp", addr)
if err != nil { if err != nil {
@ -156,8 +167,10 @@ func handleChannel(newChannel ssh.NewChannel, ports []uint32) {
close := func() { close := func() {
connection.Close() connection.Close()
rconn.Close() rconn.Close()
if *verbose {
log.Printf("Session closed") log.Printf("Session closed")
} }
}
var once sync.Once var once sync.Once
go func() { go func() {
@ -182,9 +195,9 @@ func parsePorts(portstr string) (p []uint32, err error) {
return return
} }
func loadKeys() { func loadAuthorisedKeys(authorisedkeys string) {
authorisedKeys = map[string]string{} authorisedKeys = map[string]string{}
authorisedKeysBytes, err := ioutil.ReadFile("authorized_keys") authorisedKeysBytes, err := ioutil.ReadFile(authorisedkeys)
if err != nil { if err != nil {
log.Fatal("Cannot load authorised keys") log.Fatal("Cannot load authorised keys")
} }