0.9.1: SSHServer update

This release adds support for the keyboard-interactive authentication and bumps [sshserver](https://github.com/containerssh/sshserver) to 0.9.16.

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 0.9.1: SSHServer update
+
+This release adds support for the keyboard-interactive authentication and bumps [sshserver](https://github.com/containerssh/sshserver) to 0.9.16.
+
 ## 0.9.0: Initial port
 
 This release is the initial port for metrics from ContainerSSH version 0.3.

go.mod

@@ -5,6 +5,6 @@ go 1.14
 require (
 	github.com/containerssh/geoip v0.9.4
 	github.com/containerssh/metrics v0.9.6
-	github.com/containerssh/sshserver v0.9.14
+	github.com/containerssh/sshserver v0.9.16
 	github.com/stretchr/testify v1.6.1
 )

go.sum

@@ -0,0 +1,114 @@
+github.com/containerssh/geoip v0.9.3 h1:RDj46uxB3Ew7qoTHCUClBDkqULRZJOLxYf/VqPgEuK8=
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handler.go

@@ -56,6 +56,10 @@ type metricsNetworkHandler struct {
 	disconnected bool
 }
 
+func (m *metricsNetworkHandler) OnShutdown(shutdownContext context.Context) {
+	m.backend.OnShutdown(shutdownContext)
+}
+
 func (m *metricsNetworkHandler) OnAuthPassword(username string, password []byte) (
 	response sshserver.AuthResponse,
 	reason error,
@@ -90,6 +94,26 @@ func (m *metricsNetworkHandler) OnAuthPubKey(username string, pubKey string) (
 	return response, reason
 }
 
+func (m *metricsNetworkHandler) OnAuthKeyboardInteractive(
+	user string,
+	challenge func(
+		instruction string,
+		questions sshserver.KeyboardInteractiveQuestions,
+	) (answers sshserver.KeyboardInteractiveAnswers, err error),
+) (response sshserver.AuthResponse, reason error) {
+	label := metrics.Label("authtype", "keyboard-interactive")
+	response, reason = m.backend.OnAuthKeyboardInteractive(user, challenge)
+	switch response {
+	case sshserver.AuthResponseSuccess:
+		m.handler.authSuccessMetric.Increment(m.client.IP, label)
+	case sshserver.AuthResponseFailure:
+		m.handler.authFailureMetric.Increment(m.client.IP, label)
+	case sshserver.AuthResponseUnavailable:
+		m.handler.authBackendFailureMetric.Increment(label)
+	}
+	return response, reason
+}
+
 func (m *metricsNetworkHandler) OnHandshakeFailed(reason error) {
 	m.handler.handshakeFailedMetric.Increment(m.client.IP)
 	m.backend.OnHandshakeFailed(reason)

integration_test.go

@@ -3,7 +3,6 @@ package metricsintegration_test
 import (
 	"context"
 	"fmt"
-	"io"
 	"net"
 	"testing"
 
@@ -162,6 +161,9 @@ type dummyBackendHandler struct {
 	authResponse sshserver.AuthResponse
 }
 
+func (d *dummyBackendHandler) OnClose() {
+}
+
 func (d *dummyBackendHandler) OnReady() error {
 	return nil
 }
@@ -194,6 +196,16 @@ func (d *dummyBackendHandler) OnAuthPubKey(_ string, _ string) (
 	return d.authResponse, nil
 }
 
+func (d *dummyBackendHandler) OnAuthKeyboardInteractive(
+	_ string,
+	_ func(
+		instruction string,
+		questions sshserver.KeyboardInteractiveQuestions,
+	) (answers sshserver.KeyboardInteractiveAnswers, err error),
+) (response sshserver.AuthResponse, reason error) {
+	return d.authResponse, nil
+}
+
 func (d *dummyBackendHandler) OnHandshakeFailed(_ error) {
 
 }
@@ -216,15 +228,28 @@ func (d *dummyBackendHandler) OnUnsupportedChannel(_ uint64, _ string, _ []byte)
 func (d *dummyBackendHandler) OnSessionChannel(
 	_ uint64,
 	_ []byte,
+	session sshserver.SessionChannel,
 ) (channel sshserver.SessionChannelHandler, failureReason sshserver.ChannelRejection) {
-	return d, nil
+	return &dummySession{
+		session: session,
+	}, nil
+}
+
+type dummySession struct {
+	session sshserver.SessionChannel
+}
+
+func (d *dummySession) OnClose() {
+}
+
+func (d *dummySession) OnShutdown(_ context.Context) {
 }
 
-func (d *dummyBackendHandler) OnUnsupportedChannelRequest(_ uint64, _ string, _ []byte) {
+func (d *dummySession) OnUnsupportedChannelRequest(_ uint64, _ string, _ []byte) {
 
 }
 
-func (d *dummyBackendHandler) OnFailedDecodeChannelRequest(
+func (d *dummySession) OnFailedDecodeChannelRequest(
 	_ uint64,
 	_ string,
 	_ []byte,
@@ -233,11 +258,11 @@ func (d *dummyBackendHandler) OnFailedDecodeChannelRequest(
 
 }
 
-func (d *dummyBackendHandler) OnEnvRequest(_ uint64, _ string, _ string) error {
+func (d *dummySession) OnEnvRequest(_ uint64, _ string, _ string) error {
 	return fmt.Errorf("env not supported")
 }
 
-func (d *dummyBackendHandler) OnPtyRequest(
+func (d *dummySession) OnPtyRequest(
 	_ uint64,
 	_ string,
 	_ uint32,
@@ -249,62 +274,50 @@ func (d *dummyBackendHandler) OnPtyRequest(
 	return fmt.Errorf("PTY not supported")
 }
 
-func (d *dummyBackendHandler) OnExecRequest(
+func (d *dummySession) OnExecRequest(
 	_ uint64,
 	exec string,
-	_ io.Reader,
-	stdout io.Writer,
-	_ io.Writer,
-	exit func(exitStatus sshserver.ExitStatus),
 ) error {
 	go func() {
-		_, err := stdout.Write([]byte(fmt.Sprintf("Exec request received: %s", exec)))
+		_, err := d.session.Stdout().Write([]byte(fmt.Sprintf("Exec request received: %s", exec)))
 		if err != nil {
-			exit(2)
+			d.session.ExitStatus(2)
 		} else {
-			exit(0)
+			d.session.ExitStatus(0)
 		}
 	}()
 	return nil
 }
 
-func (d *dummyBackendHandler) OnShell(
+func (d *dummySession) OnShell(
 	_ uint64,
-	_ io.Reader,
-	_ io.Writer,
-	_ io.Writer,
-	_ func(exitStatus sshserver.ExitStatus),
 ) error {
 	return fmt.Errorf("shell not supported")
 }
 
-func (d *dummyBackendHandler) OnSubsystem(
+func (d *dummySession) OnSubsystem(
 	_ uint64,
 	subsystem string,
-	_ io.Reader,
-	stdout io.Writer,
-	_ io.Writer,
-	exit func(exitStatus sshserver.ExitStatus),
 ) error {
 	if subsystem != "sftp" {
 		return fmt.Errorf("subsystem not supported")
 	}
 	go func() {
-		_, err := stdout.Write([]byte(fmt.Sprintf("Subsystem request received: %s", subsystem)))
+		_, err := d.session.Stdout().Write([]byte(fmt.Sprintf("Subsystem request received: %s", subsystem)))
 		if err != nil {
-			exit(2)
+			d.session.ExitStatus(2)
 		} else {
-			exit(0)
+			d.session.ExitStatus(0)
 		}
 	}()
 	return nil
 }
 
-func (d *dummyBackendHandler) OnSignal(_ uint64, _ string) error {
+func (d *dummySession) OnSignal(_ uint64, _ string) error {
 	return fmt.Errorf("signal not supported")
 }
 
-func (d *dummyBackendHandler) OnWindow(
+func (d *dummySession) OnWindow(
 	_ uint64,
 	_ uint32,
 	_ uint32,