func ExampleClient_Listen() {
config := &ssh.ClientConfig{
User: "******",
Auth: []ssh.AuthMethod{
ssh.Password("password"),
},
}
// Dial your ssh server.
conn, err := ssh.Dial("tcp", "localhost:22", config)
if err != nil {
log.Fatalf("unable to connect: %s", err)
}
defer conn.Close()
// Request the remote side to open port 8080 on all interfaces.
l, err := conn.Listen("tcp", "0.0.0.0:8080")
if err != nil {
log.Fatalf("unable to register tcp forward: %v", err)
}
defer l.Close()
// Serve HTTP with your SSH server acting as a reverse proxy.
http.Serve(l, http.HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
fmt.Fprintf(resp, "Hello world!\n")
}))
}
func ExampleSession_RequestPty() {
// Create client config
config := &ssh.ClientConfig{
User: "******",
Auth: []ssh.AuthMethod{
ssh.Password("password"),
},
}
// Connect to ssh server
conn, err := ssh.Dial("tcp", "localhost:22", config)
if err != nil {
log.Fatalf("unable to connect: %s", err)
}
defer conn.Close()
// Create a session
session, err := conn.NewSession()
if err != nil {
log.Fatalf("unable to create session: %s", err)
}
defer session.Close()
// Set up terminal modes
modes := ssh.TerminalModes{
ssh.ECHO: 0, // disable echoing
ssh.TTY_OP_ISPEED: 14400, // input speed = 14.4kbaud
ssh.TTY_OP_OSPEED: 14400, // output speed = 14.4kbaud
}
// Request pseudo terminal
if err := session.RequestPty("xterm", 80, 40, modes); err != nil {
log.Fatalf("request for pseudo terminal failed: %s", err)
}
// Start remote shell
if err := session.Shell(); err != nil {
log.Fatalf("failed to start shell: %s", err)
}
}
func ExampleDial() {
// An SSH client is represented with a ClientConn. Currently only
// the "password" authentication method is supported.
//
// To authenticate with the remote server you must pass at least one
// implementation of AuthMethod via the Auth field in ClientConfig.
config := &ssh.ClientConfig{
User: "******",
Auth: []ssh.AuthMethod{
ssh.Password("yourpassword"),
},
}
client, err := ssh.Dial("tcp", "yourserver.com:22", config)
if err != nil {
panic("Failed to dial: " + err.Error())
}
// Each ClientConn can support multiple interactive sessions,
// represented by a Session.
session, err := client.NewSession()
if err != nil {
panic("Failed to create session: " + err.Error())
}
defer session.Close()
// Once a Session is created, you can execute a single command on
// the remote side using the Run method.
var b bytes.Buffer
session.Stdout = &b
if err := session.Run("/usr/bin/whoami"); err != nil {
panic("Failed to run: " + err.Error())
}
fmt.Println(b.String())
}
func (s *sshTunnel) Start(readyErrCh chan<- error, errCh chan<- error) {
authMethods := []ssh.AuthMethod{}
if s.options.PrivateKey != "" {
s.logger.Debug(s.logTag, "Reading private key file '%s'", s.options.PrivateKey)
keyContents, err := ioutil.ReadFile(s.options.PrivateKey)
if err != nil {
readyErrCh <- bosherr.WrapErrorf(err, "Reading private key file '%s'", s.options.PrivateKey)
return
}
s.logger.Debug(s.logTag, "Parsing private key file '%s'", s.options.PrivateKey)
signer, err := ssh.ParsePrivateKey(keyContents)
if err != nil {
readyErrCh <- bosherr.WrapErrorf(err, "Parsing private key file '%s'", s.options.PrivateKey)
return
}
authMethods = append(authMethods, ssh.PublicKeys(signer))
}
if s.options.Password != "" {
s.logger.Debug(s.logTag, "Adding password auth method to ssh tunnel config")
keyboardInteractiveChallenge := func(
user,
instruction string,
questions []string,
echos []bool,
) (answers []string, err error) {
if len(questions) == 0 {
return []string{}, nil
}
return []string{s.options.Password}, nil
}
authMethods = append(authMethods, ssh.KeyboardInteractive(keyboardInteractiveChallenge))
authMethods = append(authMethods, ssh.Password(s.options.Password))
}
sshConfig := &ssh.ClientConfig{
User: s.options.User,
Auth: authMethods,
}
s.logger.Debug(s.logTag, "Dialing remote server at %s:%d", s.options.Host, s.options.Port)
remoteAddr := fmt.Sprintf("%s:%d", s.options.Host, s.options.Port)
retryStrategy := &SSHRetryStrategy{
TimeService: s.timeService,
ConnectionRefusedTimeout: s.connectionRefusedTimeout,
AuthFailureTimeout: s.authFailureTimeout,
}
var conn *ssh.Client
var err error
for i := 0; ; i++ {
s.logger.Debug(s.logTag, "Making attempt #%d", i)
conn, err = ssh.Dial("tcp", remoteAddr, sshConfig)
if err == nil {
break
}
if !retryStrategy.IsRetryable(err) {
readyErrCh <- bosherr.WrapError(err, "Failed to connect to remote server")
return
}
s.logger.Debug(s.logTag, "Attempt failed #%d: Dialing remote server: %s", i, err.Error())
time.Sleep(s.startDialDelay)
}
remoteListenAddr := fmt.Sprintf("127.0.0.1:%d", s.options.RemoteForwardPort)
s.logger.Debug(s.logTag, "Listening on remote server %s", remoteListenAddr)
s.remoteListener, err = conn.Listen("tcp", remoteListenAddr)
if err != nil {
readyErrCh <- bosherr.WrapError(err, "Listening on remote server")
return
}
readyErrCh <- nil
for {
remoteConn, err := s.remoteListener.Accept()
s.logger.Debug(s.logTag, "Received connection")
if err != nil {
errCh <- bosherr.WrapError(err, "Accepting connection on remote server")
}
defer func() {
if err = remoteConn.Close(); err != nil {
s.logger.Warn(s.logTag, "Failed to close remote listener connection: %s", err.Error())
}
}()
s.logger.Debug(s.logTag, "Dialing local server")
localDialAddr := fmt.Sprintf("127.0.0.1:%d", s.options.LocalForwardPort)
localConn, err := net.Dial("tcp", localDialAddr)
if err != nil {
errCh <- bosherr.WrapError(err, "Dialing local server")
return
}
go func() {
bytesNum, err := io.Copy(remoteConn, localConn)
defer func() {
if err = localConn.Close(); err != nil {
s.logger.Warn(s.logTag, "Failed to close local dial connection: %s", err.Error())
}
}()
s.logger.Debug(s.logTag, "Copying bytes from local to remote %d", bytesNum)
if err != nil {
errCh <- bosherr.WrapError(err, "Copying bytes from local to remote")
}
}()
go func() {
bytesNum, err := io.Copy(localConn, remoteConn)
defer func() {
if err = localConn.Close(); err != nil {
s.logger.Warn(s.logTag, "Failed to close local dial connection: %s", err.Error())
}
}()
s.logger.Debug(s.logTag, "Copying bytes from remote to local %d", bytesNum)
if err != nil {
errCh <- bosherr.WrapError(err, "Copying bytes from remote to local")
}
}()
}
}