Update vendor dependencies

vendor/golang.org/x/crypto/ssh/test/multi_auth_test.go

@@ -0,0 +1,144 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Tests for ssh client multi-auth
+//
+// These tests run a simple go ssh client against OpenSSH server
+// over unix domain sockets. The tests use multiple combinations
+// of password, keyboard-interactive and publickey authentication
+// methods.
+//
+// A wrapper library for making sshd PAM authentication use test
+// passwords is required in ./sshd_test_pw.so. If the library does
+// not exist these tests will be skipped. See compile instructions
+// (for linux) in file ./sshd_test_pw.c.
+
+// +build linux
+
+package test
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"golang.org/x/crypto/ssh"
+)
+
+// test cases
+type multiAuthTestCase struct {
+	authMethods         []string
+	expectedPasswordCbs int
+	expectedKbdIntCbs   int
+}
+
+// test context
+type multiAuthTestCtx struct {
+	password       string
+	numPasswordCbs int
+	numKbdIntCbs   int
+}
+
+// create test context
+func newMultiAuthTestCtx(t *testing.T) *multiAuthTestCtx {
+	password, err := randomPassword()
+	if err != nil {
+		t.Fatalf("Failed to generate random test password: %s", err.Error())
+	}
+
+	return &multiAuthTestCtx{
+		password: password,
+	}
+}
+
+// password callback
+func (ctx *multiAuthTestCtx) passwordCb() (secret string, err error) {
+	ctx.numPasswordCbs++
+	return ctx.password, nil
+}
+
+// keyboard-interactive callback
+func (ctx *multiAuthTestCtx) kbdIntCb(user, instruction string, questions []string, echos []bool) (answers []string, err error) {
+	if len(questions) == 0 {
+		return nil, nil
+	}
+
+	ctx.numKbdIntCbs++
+	if len(questions) == 1 {
+		return []string{ctx.password}, nil
+	}
+
+	return nil, fmt.Errorf("unsupported keyboard-interactive flow")
+}
+
+// TestMultiAuth runs several subtests for different combinations of password, keyboard-interactive and publickey authentication methods
+func TestMultiAuth(t *testing.T) {
+	testCases := []multiAuthTestCase{
+		// Test password,publickey authentication, assert that password callback is called 1 time
+		multiAuthTestCase{
+			authMethods:         []string{"password", "publickey"},
+			expectedPasswordCbs: 1,
+		},
+		// Test keyboard-interactive,publickey authentication, assert that keyboard-interactive callback is called 1 time
+		multiAuthTestCase{
+			authMethods:       []string{"keyboard-interactive", "publickey"},
+			expectedKbdIntCbs: 1,
+		},
+		// Test publickey,password authentication, assert that password callback is called 1 time
+		multiAuthTestCase{
+			authMethods:         []string{"publickey", "password"},
+			expectedPasswordCbs: 1,
+		},
+		// Test publickey,keyboard-interactive authentication, assert that keyboard-interactive callback is called 1 time
+		multiAuthTestCase{
+			authMethods:       []string{"publickey", "keyboard-interactive"},
+			expectedKbdIntCbs: 1,
+		},
+		// Test password,password authentication, assert that password callback is called 2 times
+		multiAuthTestCase{
+			authMethods:         []string{"password", "password"},
+			expectedPasswordCbs: 2,
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(strings.Join(testCase.authMethods, ","), func(t *testing.T) {
+			ctx := newMultiAuthTestCtx(t)
+
+			server := newServerForConfig(t, "MultiAuth", map[string]string{"AuthMethods": strings.Join(testCase.authMethods, ",")})
+			defer server.Shutdown()
+
+			clientConfig := clientConfig()
+			server.setTestPassword(clientConfig.User, ctx.password)
+
+			publicKeyAuthMethod := clientConfig.Auth[0]
+			clientConfig.Auth = nil
+			for _, authMethod := range testCase.authMethods {
+				switch authMethod {
+				case "publickey":
+					clientConfig.Auth = append(clientConfig.Auth, publicKeyAuthMethod)
+				case "password":
+					clientConfig.Auth = append(clientConfig.Auth,
+						ssh.RetryableAuthMethod(ssh.PasswordCallback(ctx.passwordCb), 5))
+				case "keyboard-interactive":
+					clientConfig.Auth = append(clientConfig.Auth,
+						ssh.RetryableAuthMethod(ssh.KeyboardInteractive(ctx.kbdIntCb), 5))
+				default:
+					t.Fatalf("Unknown authentication method %s", authMethod)
+				}
+			}
+
+			conn := server.Dial(clientConfig)
+			defer conn.Close()
+
+			if ctx.numPasswordCbs != testCase.expectedPasswordCbs {
+				t.Fatalf("passwordCallback was called %d times, expected %d times", ctx.numPasswordCbs, testCase.expectedPasswordCbs)
+			}
+
+			if ctx.numKbdIntCbs != testCase.expectedKbdIntCbs {
+				t.Fatalf("keyboardInteractiveCallback was called %d times, expected %d times", ctx.numKbdIntCbs, testCase.expectedKbdIntCbs)
+			}
+		})
+	}
+}

vendor/golang.org/x/crypto/ssh/test/sshd_test_pw.c

@@ -0,0 +1,173 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// sshd_test_pw.c
+// Wrapper to inject test password data for sshd PAM authentication
+//
+// This wrapper implements custom versions of getpwnam, getpwnam_r,
+// getspnam and getspnam_r. These functions first call their real
+// libc versions, then check if the requested user matches test user
+// specified in env variable TEST_USER and if so replace the password
+// with crypted() value of TEST_PASSWD env variable.
+//
+// Compile:
+// gcc -Wall -shared -o sshd_test_pw.so -fPIC sshd_test_pw.c
+//
+// Compile with debug:
+// gcc -DVERBOSE -Wall -shared -o sshd_test_pw.so -fPIC sshd_test_pw.c
+//
+// Run sshd:
+// LD_PRELOAD="sshd_test_pw.so" TEST_USER="..." TEST_PASSWD="..." sshd ...
+
+// +build ignore
+
+#define _GNU_SOURCE
+#include <string.h>
+#include <pwd.h>
+#include <shadow.h>
+#include <dlfcn.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#ifdef VERBOSE
+#define DEBUG(X...) fprintf(stderr, X)
+#else
+#define DEBUG(X...) while (0) { }
+#endif
+
+/* crypt() password */
+static char *
+pwhash(char *passwd) {
+  return strdup(crypt(passwd, "$6$"));
+}
+
+/* Pointers to real functions in libc */
+static struct passwd * (*real_getpwnam)(const char *) = NULL;
+static int (*real_getpwnam_r)(const char *, struct passwd *, char *, size_t, struct passwd **) = NULL;
+static struct spwd * (*real_getspnam)(const char *) = NULL;
+static int (*real_getspnam_r)(const char *, struct spwd *, char *, size_t, struct spwd **) = NULL;
+
+/* Cached test user and test password */
+static char *test_user = NULL;
+static char *test_passwd_hash = NULL;
+
+static void
+init(void) {
+  /* Fetch real libc function pointers */
+  real_getpwnam = dlsym(RTLD_NEXT, "getpwnam");
+  real_getpwnam_r = dlsym(RTLD_NEXT, "getpwnam_r");
+  real_getspnam = dlsym(RTLD_NEXT, "getspnam");
+  real_getspnam_r = dlsym(RTLD_NEXT, "getspnam_r");
+  
+  /* abort if env variables are not defined */
+  if (getenv("TEST_USER") == NULL || getenv("TEST_PASSWD") == NULL) {
+    fprintf(stderr, "env variables TEST_USER and TEST_PASSWD are missing\n");
+    abort();
+  }
+
+  /* Fetch test user and test password from env */
+  test_user = strdup(getenv("TEST_USER"));
+  test_passwd_hash = pwhash(getenv("TEST_PASSWD"));
+
+  DEBUG("sshd_test_pw init():\n");
+  DEBUG("\treal_getpwnam: %p\n", real_getpwnam);
+  DEBUG("\treal_getpwnam_r: %p\n", real_getpwnam_r);
+  DEBUG("\treal_getspnam: %p\n", real_getspnam);
+  DEBUG("\treal_getspnam_r: %p\n", real_getspnam_r);
+  DEBUG("\tTEST_USER: '%s'\n", test_user);
+  DEBUG("\tTEST_PASSWD: '%s'\n", getenv("TEST_PASSWD"));
+  DEBUG("\tTEST_PASSWD_HASH: '%s'\n", test_passwd_hash);
+}
+
+static int
+is_test_user(const char *name) {
+  if (test_user != NULL && strcmp(test_user, name) == 0)
+    return 1;
+  return 0;
+}
+
+/* getpwnam */
+
+struct passwd *
+getpwnam(const char *name) {
+  struct passwd *pw;
+
+  DEBUG("sshd_test_pw getpwnam(%s)\n", name);
+  
+  if (real_getpwnam == NULL)
+    init();
+  if ((pw = real_getpwnam(name)) == NULL)
+    return NULL;
+
+  if (is_test_user(name))
+    pw->pw_passwd = strdup(test_passwd_hash);
+      
+  return pw;
+}
+
+/* getpwnam_r */
+
+int
+getpwnam_r(const char *name,
+	   struct passwd *pwd,
+	   char *buf,
+	   size_t buflen,
+	   struct passwd **result) {
+  int r;
+
+  DEBUG("sshd_test_pw getpwnam_r(%s)\n", name);
+  
+  if (real_getpwnam_r == NULL)
+    init();
+  if ((r = real_getpwnam_r(name, pwd, buf, buflen, result)) != 0 || *result == NULL)
+    return r;
+
+  if (is_test_user(name))
+    pwd->pw_passwd = strdup(test_passwd_hash);
+  
+  return 0;
+}
+
+/* getspnam */
+
+struct spwd *
+getspnam(const char *name) {
+  struct spwd *sp;
+
+  DEBUG("sshd_test_pw getspnam(%s)\n", name);
+  
+  if (real_getspnam == NULL)
+    init();
+  if ((sp = real_getspnam(name)) == NULL)
+    return NULL;
+
+  if (is_test_user(name))
+    sp->sp_pwdp = strdup(test_passwd_hash);
+  
+  return sp;
+}
+
+/* getspnam_r */
+
+int
+getspnam_r(const char *name,
+	   struct spwd *spbuf,
+	   char *buf,
+	   size_t buflen,
+	   struct spwd **spbufp) {
+  int r;
+
+  DEBUG("sshd_test_pw getspnam_r(%s)\n", name);
+  
+  if (real_getspnam_r == NULL)
+    init();
+  if ((r = real_getspnam_r(name, spbuf, buf, buflen, spbufp)) != 0)
+    return r;
+
+  if (is_test_user(name))
+    spbuf->sp_pwdp = strdup(test_passwd_hash);
+  
+  return r;
+}

vendor/golang.org/x/crypto/ssh/test/test_unix_test.go

@@ -10,6 +10,8 @@ package test
 
 import (
 	"bytes"
+	"crypto/rand"
+	"encoding/base64"
 	"fmt"
 	"io/ioutil"
 	"log"
@@ -25,7 +27,8 @@ import (
 	"golang.org/x/crypto/ssh/testdata"
 )
 
-const sshdConfig = `
+const (
+	defaultSshdConfig = `
 Protocol 2
 Banner {{.Dir}}/banner
 HostKey {{.Dir}}/id_rsa
@@ -50,8 +53,17 @@ RhostsRSAAuthentication no
 HostbasedAuthentication no
 PubkeyAcceptedKeyTypes=*
 `
+	multiAuthSshdConfigTail = `
+UsePAM yes
+PasswordAuthentication yes
+ChallengeResponseAuthentication yes
+AuthenticationMethods {{.AuthMethods}}
+`
+)
 
-var configTmpl = template.Must(template.New("").Parse(sshdConfig))
+var configTmpl = map[string]*template.Template{
+	"default":   template.Must(template.New("").Parse(defaultSshdConfig)),
+	"MultiAuth": template.Must(template.New("").Parse(defaultSshdConfig + multiAuthSshdConfigTail))}
 
 type server struct {
 	t          *testing.T
@@ -60,6 +72,10 @@ type server struct {
 	cmd        *exec.Cmd
 	output     bytes.Buffer // holds stderr from sshd process
 
+	testUser     string // test username for sshd
+	testPasswd   string // test password for sshd
+	sshdTestPwSo string // dynamic library to inject a custom password into sshd
+
 	// Client half of the network connection.
 	clientConn net.Conn
 }
@@ -186,6 +202,20 @@ func (s *server) TryDialWithAddr(config *ssh.ClientConfig, addr string) (*ssh.Cl
 	s.cmd.Stdin = f
 	s.cmd.Stdout = f
 	s.cmd.Stderr = &s.output
+
+	if s.sshdTestPwSo != "" {
+		if s.testUser == "" {
+			s.t.Fatal("user missing from sshd_test_pw.so config")
+		}
+		if s.testPasswd == "" {
+			s.t.Fatal("password missing from sshd_test_pw.so config")
+		}
+		s.cmd.Env = append(os.Environ(),
+			fmt.Sprintf("LD_PRELOAD=%s", s.sshdTestPwSo),
+			fmt.Sprintf("TEST_USER=%s", s.testUser),
+			fmt.Sprintf("TEST_PASSWD=%s", s.testPasswd))
+	}
+
 	if err := s.cmd.Start(); err != nil {
 		s.t.Fail()
 		s.Shutdown()
@@ -236,11 +266,49 @@ func writeFile(path string, contents []byte) {
 	}
 }
 
+// generate random password
+func randomPassword() (string, error) {
+	b := make([]byte, 12)
+	_, err := rand.Read(b)
+	if err != nil {
+		return "", err
+	}
+	return base64.RawURLEncoding.EncodeToString(b), nil
+}
+
+// setTestPassword is used for setting user and password data for sshd_test_pw.so
+// This function also checks that ./sshd_test_pw.so exists and if not calls s.t.Skip()
+func (s *server) setTestPassword(user, passwd string) error {
+	wd, _ := os.Getwd()
+	wrapper := filepath.Join(wd, "sshd_test_pw.so")
+	if _, err := os.Stat(wrapper); err != nil {
+		s.t.Skip(fmt.Errorf("sshd_test_pw.so is not available"))
+		return err
+	}
+
+	s.sshdTestPwSo = wrapper
+	s.testUser = user
+	s.testPasswd = passwd
+	return nil
+}
+
 // newServer returns a new mock ssh server.
 func newServer(t *testing.T) *server {
+	return newServerForConfig(t, "default", map[string]string{})
+}
+
+// newServerForConfig returns a new mock ssh server.
+func newServerForConfig(t *testing.T, config string, configVars map[string]string) *server {
 	if testing.Short() {
 		t.Skip("skipping test due to -short")
 	}
+	u, err := user.Current()
+	if err != nil {
+		t.Fatalf("user.Current: %v", err)
+	}
+	if u.Name == "root" {
+		t.Skip("skipping test because current user is root")
+	}
 	dir, err := ioutil.TempDir("", "sshtest")
 	if err != nil {
 		t.Fatal(err)
@@ -249,9 +317,11 @@ func newServer(t *testing.T) *server {
 	if err != nil {
 		t.Fatal(err)
 	}
-	err = configTmpl.Execute(f, map[string]string{
-		"Dir": dir,
-	})
+	if _, ok := configTmpl[config]; ok == false {
+		t.Fatal(fmt.Errorf("Invalid server config '%s'", config))
+	}
+	configVars["Dir"] = dir
+	err = configTmpl[config].Execute(f, configVars)
 	if err != nil {
 		t.Fatal(err)
 	}