ssh: pty, keepAlive, domain matcher, refactor

internal/api/server.go

@@ -61,7 +61,7 @@ func (p *pluginAPI) receiverForContext(ctx context.Context) plugin.Plugin {
 }
 
 func StartPluginAPI() {
-	port := config.Default.PluginAPIPort
+	port := config.Default.API.PluginPort
 	if port == 0 {
 		port = plugin2.DefaultPort
 	}

internal/config/model.go

@@ -12,12 +12,17 @@ var Default Config
 
 type Config struct {
 	Debug         bool         `mapstructure:"debug"`
-	PluginAPIPort int          `mapstructure:"plugin_api_port" validate:"gte=0,lte=65535"`
+	API           API          `mapstructure:"api"`
 	Docker        DockerConfig `mapstructure:"docker"`
 	DefaultServer string       `mapstructure:"default_server"`
 	Servers       []Server     `mapstructure:"servers"`
 }
 
+type API struct {
+	WebPort    int `mapstructure:"web_port" validate:"gte=0,lte=65535"`
+	PluginPort int `mapstructure:"plugin_port" validate:"gte=0,lte=65535"`
+}
+
 type DockerConfig struct {
 	FromEnv   *bool  `mapstructure:"from_env,omitempty"`
 	CertPath  string `mapstructure:"cert_path"`

internal/server/driver/ssh/driver.go

@@ -3,8 +3,10 @@ package ssh
 import (
 	"context"
 	"errors"
+	"fmt"
 	"net"
 	"path"
+	"regexp"
 	"strconv"
 	"sync"
 
@@ -21,11 +23,12 @@ var ErrAlreadyInUse = errors.New("domain is already in use")
 
 type SSH struct {
 	base.Base
-	params Params
+	params       Params
-	auth   []ssh.AuthMethod
+	auth         []ssh.AuthMethod
-	conns  map[string]conn
+	conns        map[string]conn
-	rw     sync.RWMutex
+	rw           sync.RWMutex
-	wg     sync.WaitGroup
+	wg           sync.WaitGroup
+	domainRegExp *regexp.Regexp
 }
 
 type conn struct {
@@ -42,26 +45,58 @@ func New(ctx context.Context, name string, params config.DriverParams) (base.Dri
 	if err := util.UnmarshalParams(params, &drv.params); err != nil {
 		return nil, err
 	}
+	matcher, err := makeDomainCatchRegExp(drv.params.DomainExtractRegex)
+	if err != nil {
+		return nil, fmt.Errorf("invalid domain_extract_regex: %w", err)
+	}
+	drv.domainRegExp = matcher
 	drv.populateFromSSHConfig()
 	drv.auth = drv.authenticators()
 	return drv, nil
 }
 
-func (d *SSH) forward(val sshtun.Forward) conn {
+func (d *SSH) forward(val sshtun.Forward, domainMatcher func(string)) conn {
 	tun := sshtun.New(d.params.Address,
 		d.params.Auth.User,
-		d.params.FakeRemoteHost,
 		val,
 		d.auth,
+		sshtun.SessionConfig{
+			NoPTY:             d.params.NoPTY,
+			FakeRemoteHost:    d.params.FakeRemoteHost,
+			KeepAliveInterval: uint(d.params.KeepAlive.Interval),
+			KeepAliveMax:      uint(d.params.KeepAlive.MaxAttempts),
+		},
 		d.Log())
 	ctx, cancel := context.WithCancel(d.Context())
 	tunDbgLog := d.Log().With("ssh-output", val.Remote.String())
 	go tun.Connect(ctx,
-		sshtun.StdoutPrinterBannerCallback(tunDbgLog),
+		sshtun.BannerDebugLogCallback(tunDbgLog),
-		sshtun.StdoutPrinterSessionCallback(tunDbgLog))
+		sshtun.OutputReaderCallback(func(msg string) {
+			d.Log().Debug(msg)
+			if domainMatcher != nil {
+				domainMatcher(msg)
+			}
+		}))
 	return conn{ctx: ctx, cancel: cancel, tun: tun}
 }
 
+func (d *SSH) makeDomainMatcherFunc(containerID string) func(string) {
+	if d.domainRegExp == nil {
+		return nil
+	}
+	return func(msg string) {
+		domain := d.domainRegExp.FindString(msg)
+		if domain == "" {
+			return
+		}
+		d.PushEventStatus(dto.EventStatus{
+			Type:   dto.EventStart,
+			ID:     containerID,
+			Domain: domain,
+		})
+	}
+}
+
 func (d *SSH) populateFromSSHConfig() {
 	if d.params.Auth.Directory == "" {
 		return
@@ -94,9 +129,9 @@ func (d *SSH) Handle(event dto.Event) error {
 			return ErrAlreadyInUse
 		}
 		conn := d.forward(sshtun.Forward{
-			Local:  sshtun.AddrToEndpoint(net.JoinHostPort(event.Container.IP.String(), strconv.Itoa(int(event.Container.Port)))),
+			Local:  d.localEndpoint(event.Container.IP, event.Container.Port),
 			Remote: d.remoteEndpoint(event.Container.RemoteHost),
-		})
+		}, d.makeDomainMatcherFunc(event.Container.ID))
 		d.conns[event.Container.ID] = conn
 		d.wg.Add(1)
 	case dto.EventStop:
@@ -106,17 +141,27 @@ func (d *SSH) Handle(event dto.Event) error {
 		}
 		conn.cancel()
 		delete(d.conns, event.Container.ID)
+		d.propagateStop(event.Container.ID)
 		d.wg.Done()
 	case dto.EventShutdown:
 		for id, conn := range d.conns {
 			conn.cancel()
 			delete(d.conns, id)
+			d.propagateStop(id)
 			d.wg.Done()
 		}
 	}
 	return nil
 }
 
+func (d *SSH) propagateStop(containerID string) {
+	d.PushEventStatus(dto.EventStatus{Type: dto.EventStop, ID: containerID})
+}
+
+func (d *SSH) localEndpoint(ip net.IP, port uint16) sshtun.Endpoint {
+	return sshtun.AddrToEndpoint(net.JoinHostPort(ip.String(), strconv.Itoa(int(port))))
+}
+
 func (d *SSH) remoteEndpoint(remoteHost string) sshtun.Endpoint {
 	port := int(d.params.ForwardPort)
 	if port == 0 {

internal/server/driver/ssh/params.go

@@ -1,6 +1,8 @@
 package ssh
 
 import (
+	"errors"
+
 	"github.com/Neur0toxine/sshpoke/internal/server/driver/ssh/types"
 	"github.com/Neur0toxine/sshpoke/internal/server/driver/util"
 )
@@ -11,16 +13,19 @@ type Params struct {
 	ForwardPort        uint16           `mapstructure:"forward_port"`
 	Auth               types.Auth       `mapstructure:"auth"`
 	KeepAlive          types.KeepAlive  `mapstructure:"keepalive"`
-	Domain             string           `mapstructure:"domain"`
-	DomainProto        string           `mapstructure:"domain_proto"`
 	DomainExtractRegex string           `mapstructure:"domain_extract_regex" validate:"validregexp"`
 	Mode               types.DomainMode `mapstructure:"mode" validate:"required,oneof=single multi"`
 	FakeRemoteHost     bool             `mapstructure:"fake_remote_host"`
+	NoPTY              bool             `mapstructure:"nopty"`
+	Commands           types.Commands   `mapstructure:"commands"`
 }
 
 func (p *Params) Validate() error {
 	if err := util.Validator.Struct(p); err != nil {
 		return err
 	}
+	if p.NoPTY && (len(p.Commands.OnConnect) > 0 || len(p.Commands.OnDisconnect) > 0) {
+		return errors.New("commands aren't available without PTY (nopty = true)")
+	}
 	return p.Auth.Validate()
 }

internal/server/driver/ssh/regexp.go

@@ -0,0 +1,28 @@
+package ssh
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+)
+
+var builtInRegExps = map[string]*regexp.Regexp{
+	"webUrl":   regexp.MustCompile(`(?m)https?:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)`),
+	"httpUrl":  regexp.MustCompile(`(?m)http:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)`),
+	"httpsUrl": regexp.MustCompile(`(?m)https:\/\/(?:www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b(?:[-a-zA-Z0-9()@:%_\+.~#?&\/=]*)`),
+}
+
+func makeDomainCatchRegExp(expr string) (*regexp.Regexp, error) {
+	if expr == "" {
+		return nil, nil
+	}
+	if strings.HasPrefix(expr, "!") {
+		exprName := expr[1:]
+		builtIn, found := builtInRegExps[exprName]
+		if !found {
+			return nil, fmt.Errorf("no builtin regexp with name '%s'", exprName)
+		}
+		return builtIn, nil
+	}
+	return regexp.Compile(expr)
+}

internal/server/driver/ssh/sshtun/connect.go

@@ -0,0 +1,171 @@
+package sshtun
+
+import (
+	"context"
+	"net"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/Neur0toxine/sshpoke/pkg/proto/ssh"
+	"github.com/function61/gokit/app/backoff"
+	"go.uber.org/zap"
+)
+
+type SessionCallback func(*ssh.Session)
+
+var NoopSessionCallback SessionCallback = func(*ssh.Session) {}
+
+type Tunnel struct {
+	user        string
+	address     Endpoint
+	forward     Forward
+	authMethods []ssh.AuthMethod
+	log         *zap.SugaredLogger
+	sessConfig  SessionConfig
+	connected   atomic.Bool
+}
+
+type SessionConfig struct {
+	NoPTY             bool
+	FakeRemoteHost    bool
+	KeepAliveInterval uint
+	KeepAliveMax      uint
+}
+
+func New(address, user string, forward Forward, auth []ssh.AuthMethod, sc SessionConfig, log *zap.SugaredLogger) *Tunnel {
+	return &Tunnel{
+		address:     AddrToEndpoint(address),
+		user:        user,
+		forward:     forward,
+		authMethods: auth,
+		sessConfig:  sc,
+		log:         log.With(zap.String("sshServer", address)),
+	}
+}
+
+func (t *Tunnel) Connect(ctx context.Context, bannerCb ssh.BannerCallback, sessionCb SessionCallback) {
+	if t.connected.Load() {
+		return
+	}
+
+	defer t.connected.Store(false)
+	backoffTime := backoff.ExponentialWithCappedMax(100*time.Millisecond, 5*time.Second)
+	for {
+		t.connected.Store(true)
+		err := t.connect(ctx, bannerCb, sessionCb)
+		if err != nil {
+			t.log.Error("connect error: ", err)
+		}
+
+		select {
+		case <-ctx.Done():
+			return
+		default:
+		}
+
+		time.Sleep(backoffTime())
+	}
+}
+
+// connect once to the SSH server. if the connection breaks, we return error and the caller
+// will try to re-connect
+func (t *Tunnel) connect(ctx context.Context, bannerCb ssh.BannerCallback, sessionCb SessionCallback) error {
+	t.log.Debug("connecting")
+	sshConfig := &ssh.ClientConfig{
+		User:            t.user,
+		Auth:            t.authMethods,
+		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
+		BannerCallback:  bannerCb,
+	}
+
+	var sshClient *ssh.Client
+	var errConnect error
+
+	sshClient, errConnect = dialSSH(ctx, t.address.String(), sshConfig)
+	if errConnect != nil {
+		return errConnect
+	}
+
+	defer sshClient.Close()
+	defer t.log.Debug("disconnecting")
+
+	t.log.Debug("connected")
+	listenerStopped := make(chan error)
+
+	var wg sync.WaitGroup
+	sess, err := sshClient.NewSession()
+	if err != nil {
+		t.log.Errorf("session error: %s", err)
+		return err
+	}
+	defer sess.Close()
+
+	if sessionCb == nil {
+		sessionCb = func(*ssh.Session) {}
+	}
+
+	if !t.sessConfig.NoPTY {
+		err = sess.RequestPty("xterm", 80, 40, ssh.TerminalModes{
+			ssh.ECHO:  0,
+			ssh.IGNCR: 1,
+		})
+		if err != nil {
+			t.log.Warnf("PTY allocation failed: %s", err.Error())
+		} else {
+			if err := sess.Shell(); err != nil {
+				t.log.Warnf("failed to start shell: %s", err.Error())
+			}
+		}
+	}
+
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		sessionCb(sess)
+	}()
+
+	wg.Add(1)
+	reverseErr := make(chan error)
+	go func() {
+		defer wg.Done()
+		reverseErr <- t.reverseForwardOnePort(sshClient, listenerStopped)
+	}()
+
+	wg.Add(1)
+	go t.keepAlive(ctx, sshClient, &wg)
+
+	if err := <-reverseErr; err != nil {
+		return err
+	}
+
+	select {
+	case <-ctx.Done():
+		return nil
+	case listenerFirstErr := <-listenerStopped:
+		select {
+		case <-ctx.Done():
+			return nil
+		default:
+			return listenerFirstErr
+		}
+	}
+}
+
+func dialSSH(ctx context.Context, addr string, sshConfig *ssh.ClientConfig) (*ssh.Client, error) {
+	dialer := net.Dialer{
+		Timeout: 10 * time.Second,
+	}
+
+	conn, err := dialer.DialContext(ctx, "tcp", addr)
+	if err != nil {
+		return nil, err
+	}
+
+	clConn, newChan, reqChan, err := ssh.NewClientConn(conn, addr, sshConfig)
+	if err != nil {
+		return nil, err
+	}
+
+	return ssh.NewClient(clConn, newChan, reqChan), nil
+}

internal/server/driver/ssh/sshtun/forward.go

@@ -4,8 +4,12 @@ import (
 	"fmt"
 	"net"
 	"strconv"
+	"strings"
 
 	"github.com/Neur0toxine/sshpoke/pkg/errtools"
+	"github.com/Neur0toxine/sshpoke/pkg/proto/ssh"
+	"github.com/function61/gokit/io/bidipipe"
+	"go.uber.org/zap"
 )
 
 type Forward struct {
@@ -35,3 +39,77 @@ type Endpoint struct {
 func (endpoint *Endpoint) String() string {
 	return fmt.Sprintf("%s:%d", endpoint.Host, endpoint.Port)
 }
+
+func (t *Tunnel) ipFromAddr(addr net.Addr) net.IP {
+	host, _, _ := net.SplitHostPort(addr.String())
+	return net.ParseIP(host)
+}
+
+//	blocking flow: calls Listen() on the SSH connection, and if succeeds returns non-nil error
+//
+// nonblocking flow: if Accept() call fails, stops goroutine and returns error on ch listenerStopped
+func (t *Tunnel) reverseForwardOnePort(sshClient *ssh.Client, listenerStopped chan<- error) error {
+	var (
+		listener net.Listener
+		err      error
+	)
+	if t.sessConfig.FakeRemoteHost {
+		listener, err = sshClient.ListenTCP(&net.TCPAddr{
+			IP:   t.ipFromAddr(sshClient.Conn.RemoteAddr()),
+			Port: t.forward.Remote.Port,
+		}, t.forward.Remote.Host)
+	} else {
+		listener, err = sshClient.Listen("tcp", t.forward.Remote.String())
+	}
+	if err != nil {
+		return err
+	}
+
+	go func() {
+		defer listener.Close()
+		t.log.Debugf("forwarding %s <- %s", t.forward.Local.String(), t.forward.Remote.String())
+
+		for {
+			client, err := listener.Accept()
+			if err != nil {
+				listenerStopped <- fmt.Errorf("error on Accept(): %w", err)
+				return
+			}
+
+			go handleReverseForwardConn(client, t.forward, t.log)
+		}
+	}()
+
+	return nil
+}
+
+func handleReverseForwardConn(client net.Conn, forward Forward, log *zap.SugaredLogger) {
+	defer client.Close()
+
+	remote, err := net.Dial("tcp", forward.Local.String())
+	if err != nil {
+		log.Errorf("cannot dial local service: %s", err.Error())
+		return
+	}
+
+	log.Debugf("proxying %s <-> %s", forward.Local.String(), client.RemoteAddr())
+
+	// pipe data in both directions:
+	// - client => remote
+	// - remote => client
+	//
+	// - in effect, we act as a proxy between the reverse tunnel's client and locally-dialed
+	//   remote endpoint.
+	// - the "client" and "remote" strings we give Pipe() is just for error&log messages
+	// - this blocks until either of the parties' socket closes (or breaks)
+	if err := bidipipe.Pipe(
+		bidipipe.WithName("client", client),
+		bidipipe.WithName("remote", remote),
+	); err != nil {
+		// we can safely ignore those errors.
+		if strings.Contains(err.Error(), "use of closed network connection") {
+			return
+		}
+		log.Error(err)
+	}
+}

internal/server/driver/ssh/sshtun/keepalive.go

@@ -0,0 +1,62 @@
+package sshtun
+
+import (
+	"context"
+	"io"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/Neur0toxine/sshpoke/pkg/proto/ssh"
+)
+
+// keepAlive periodically sends messages to invoke a response.
+// If the server does not respond after some period of time,
+// assume that the underlying net.Conn abruptly died.
+func (t *Tunnel) keepAlive(ctx context.Context, client *ssh.Client, wg *sync.WaitGroup) {
+	defer wg.Done()
+	if t.sessConfig.KeepAliveInterval == 0 || t.sessConfig.KeepAliveMax == 0 {
+		return
+	}
+
+	// Detect when the SSH connection is closed.
+	wait := make(chan error, 1)
+	wg.Add(1)
+	go func() {
+		defer wg.Done()
+		wait <- client.Wait()
+	}()
+
+	// Repeatedly check if the remote server is still alive.
+	var aliveCount int32
+	ticker := time.NewTicker(time.Duration(t.sessConfig.KeepAliveInterval) * time.Second)
+	defer ticker.Stop()
+	for {
+		select {
+		case <-ctx.Done():
+			t.log.Debug("stopping keep-alive...")
+			_ = client.Close()
+			return
+		case err := <-wait:
+			if err != nil && err != io.EOF {
+				t.log.Error("ssh error:", err)
+			}
+			return
+		case <-ticker.C:
+			if n := atomic.AddInt32(&aliveCount, 1); n > int32(t.sessConfig.KeepAliveMax) {
+				t.log.Error("keep-alive failed, closing connection...")
+				_ = client.Close()
+				return
+			}
+		}
+
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			_, _, err := client.SendRequest("keepalive@openssh.com", true, nil)
+			if err == nil {
+				atomic.StoreInt32(&aliveCount, 0)
+			}
+		}()
+	}
+}

internal/server/driver/ssh/sshtun/printer.go

@@ -9,7 +9,7 @@ import (
 	"go.uber.org/zap"
 )
 
-func StdoutPrinterSessionCallback(log *zap.SugaredLogger) SessionCallback {
+func OutputReaderCallback(callback func(string)) SessionCallback {
 	return func(session *ssh.Session) {
 		stdout, err := session.StdoutPipe()
 		if err != nil {
@@ -27,7 +27,7 @@ func StdoutPrinterSessionCallback(log *zap.SugaredLogger) SessionCallback {
 		combined.Read(func(r io.Reader) error {
 			scan := bufio.NewScanner(r)
 			for scan.Scan() {
-				log.Debug(scan.Text())
+				callback(scan.Text())
 			}
 			return nil
 		})
@@ -35,7 +35,7 @@ func StdoutPrinterSessionCallback(log *zap.SugaredLogger) SessionCallback {
 	}
 }
 
-func StdoutPrinterBannerCallback(log *zap.SugaredLogger) ssh.BannerCallback {
+func BannerDebugLogCallback(log *zap.SugaredLogger) ssh.BannerCallback {
 	return func(msg string) error {
 		log.Debug(msg)
 		return nil

internal/server/driver/ssh/sshtun/ssh.go

@@ -1,224 +0,0 @@
-package sshtun
-
-import (
-	"context"
-	"fmt"
-	"net"
-	"strings"
-	"sync"
-	"sync/atomic"
-	"time"
-
-	"github.com/Neur0toxine/sshpoke/pkg/proto/ssh"
-	"github.com/function61/gokit/app/backoff"
-	"github.com/function61/gokit/io/bidipipe"
-	"go.uber.org/zap"
-)
-
-type SessionCallback func(*ssh.Session)
-
-var NoopSessionCallback SessionCallback = func(*ssh.Session) {}
-
-type Tunnel struct {
-	user           string
-	address        Endpoint
-	forward        Forward
-	authMethods    []ssh.AuthMethod
-	log            *zap.SugaredLogger
-	connected      atomic.Bool
-	fakeRemoteHost bool
-}
-
-func New(address, user string, fakeRemoteHost bool,
-	forward Forward, auth []ssh.AuthMethod, log *zap.SugaredLogger) *Tunnel {
-	return &Tunnel{
-		address:        AddrToEndpoint(address),
-		user:           user,
-		fakeRemoteHost: fakeRemoteHost,
-		forward:        forward,
-		authMethods:    auth,
-		log:            log.With(zap.String("sshServer", address)),
-	}
-}
-
-func (c *Tunnel) Connect(ctx context.Context, bannerCb ssh.BannerCallback, sessionCb SessionCallback) {
-	if c.connected.Load() {
-		return
-	}
-
-	defer c.connected.Store(false)
-	backoffTime := backoff.ExponentialWithCappedMax(100*time.Millisecond, 5*time.Second)
-	for {
-		c.connected.Store(true)
-		err := c.connect(ctx, bannerCb, sessionCb)
-		if err != nil {
-			c.log.Error("connect error:", err)
-		}
-
-		select {
-		case <-ctx.Done():
-			return
-		default:
-		}
-
-		time.Sleep(backoffTime())
-	}
-}
-
-// connect once to the SSH server. if the connection breaks, we return error and the caller
-// will try to re-connect
-func (c *Tunnel) connect(ctx context.Context, bannerCb ssh.BannerCallback, sessionCb SessionCallback) error {
-	c.log.Debug("connecting")
-	sshConfig := &ssh.ClientConfig{
-		User:            c.user,
-		Auth:            c.authMethods,
-		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
-		BannerCallback:  bannerCb,
-	}
-
-	var sshClient *ssh.Client
-	var errConnect error
-
-	sshClient, errConnect = dialSSH(ctx, c.address.String(), sshConfig)
-	if errConnect != nil {
-		return errConnect
-	}
-
-	defer sshClient.Close()
-	defer c.log.Debug("disconnecting")
-
-	c.log.Debug("connected")
-	listenerStopped := make(chan error)
-
-	var wg sync.WaitGroup
-	sess, err := sshClient.NewSession()
-	if err != nil {
-		c.log.Errorf("session error: %s", err)
-		return err
-	}
-	defer sess.Close()
-
-	if sessionCb == nil {
-		sessionCb = func(*ssh.Session) {}
-	}
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-		sessionCb(sess)
-	}()
-
-	wg.Add(1)
-	reverseErr := make(chan error)
-	go func() {
-		defer wg.Done()
-		reverseErr <- c.reverseForwardOnePort(sshClient, listenerStopped)
-	}()
-
-	if err := <-reverseErr; err != nil {
-		return err
-	}
-
-	select {
-	case <-ctx.Done():
-		return nil
-	case listenerFirstErr := <-listenerStopped:
-		select {
-		case <-ctx.Done():
-			return nil
-		default:
-			return listenerFirstErr
-		}
-	}
-}
-
-//	blocking flow: calls Listen() on the SSH connection, and if succeeds returns non-nil error
-//
-// nonblocking flow: if Accept() call fails, stops goroutine and returns error on ch listenerStopped
-func (c *Tunnel) reverseForwardOnePort(sshClient *ssh.Client, listenerStopped chan<- error) error {
-	var (
-		listener net.Listener
-		err      error
-	)
-	if c.fakeRemoteHost {
-		listener, err = sshClient.ListenTCP(&net.TCPAddr{
-			IP:   c.ipFromAddr(sshClient.Conn.RemoteAddr()),
-			Port: c.forward.Remote.Port,
-		}, c.forward.Remote.Host)
-	} else {
-		listener, err = sshClient.Listen("tcp", c.forward.Remote.String())
-	}
-	if err != nil {
-		return err
-	}
-
-	go func() {
-		defer listener.Close()
-		c.log.Debugf("forwarding %s <- %s", c.forward.Local.String(), c.forward.Remote.String())
-
-		for {
-			client, err := listener.Accept()
-			if err != nil {
-				listenerStopped <- fmt.Errorf("error on Accept(): %w", err)
-				return
-			}
-
-			go handleReverseForwardConn(client, c.forward, c.log)
-		}
-	}()
-
-	return nil
-}
-
-func (c *Tunnel) ipFromAddr(addr net.Addr) net.IP {
-	host, _, _ := net.SplitHostPort(addr.String())
-	return net.ParseIP(host)
-}
-
-func handleReverseForwardConn(client net.Conn, forward Forward, log *zap.SugaredLogger) {
-	defer client.Close()
-
-	remote, err := net.Dial("tcp", forward.Local.String())
-	if err != nil {
-		log.Errorf("cannot dial local service: %s", err.Error())
-		return
-	}
-
-	log.Debugf("proxying %s <-> %s", forward.Local.String(), client.RemoteAddr())
-
-	// pipe data in both directions:
-	// - client => remote
-	// - remote => client
-	//
-	// - in effect, we act as a proxy between the reverse tunnel's client and locally-dialed
-	//   remote endpoint.
-	// - the "client" and "remote" strings we give Pipe() is just for error&log messages
-	// - this blocks until either of the parties' socket closes (or breaks)
-	if err := bidipipe.Pipe(
-		bidipipe.WithName("client", client),
-		bidipipe.WithName("remote", remote),
-	); err != nil {
-		// we can safely ignore those errors.
-		if strings.Contains(err.Error(), "use of closed network connection") {
-			return
-		}
-		log.Error(err)
-	}
-}
-
-func dialSSH(ctx context.Context, addr string, sshConfig *ssh.ClientConfig) (*ssh.Client, error) {
-	dialer := net.Dialer{
-		Timeout: 10 * time.Second,
-	}
-
-	conn, err := dialer.DialContext(ctx, "tcp", addr)
-	if err != nil {
-		return nil, err
-	}
-
-	clConn, newChan, reqChan, err := ssh.NewClientConn(conn, addr, sshConfig)
-	if err != nil {
-		return nil, err
-	}
-
-	return ssh.NewClient(clConn, newChan, reqChan), nil
-}

internal/server/driver/ssh/types/commands.go

@@ -0,0 +1,6 @@
+package types
+
+type Commands struct {
+	OnConnect    []string `mapstructure:"on_connect"`
+	OnDisconnect []string `mapstructure:"on_disconnect"`
+}

internal/server/driver/util/validator.go

@@ -9,7 +9,7 @@ import (
 var Validator *validator.Validate
 
 func init() {
-	Validator = validator.New()
+	Validator = validator.New(validator.WithRequiredStructEnabled())
 	_ = Validator.RegisterValidation("validregexp", isValidRegExp)
 }
 

internal/server/manager.go

@@ -89,6 +89,8 @@ func (m *Manager) eventStatusCallback(serverName string) base.EventStatusCallbac
 }
 
 func (m *Manager) processEventStatus(serverName string, event dto.EventStatus) {
+	logger.Sugar.Debugw("received EventStatus from server",
+		"serverName", serverName, "eventStatus", event)
 	m.statusLock.RLock()
 	_, exists := m.statusMap[serverName]
 	if !exists {

pkg/dto/models.go

@@ -12,6 +12,22 @@ const (
 	EventUnknown
 )
 
+var eventTypeNames = map[EventType]string{
+	EventStart:    "start",
+	EventStop:     "stop",
+	EventShutdown: "shutdown",
+	EventError:    "error",
+	EventUnknown:  "unknown",
+}
+
+func (e EventType) String() string {
+	name, ok := eventTypeNames[e]
+	if ok {
+		return name
+	}
+	return eventTypeNames[EventUnknown]
+}
+
 func TypeFromAction(action string) EventType {
 	switch action {
 	case "start":