- markus@cvs.openbsd.org 2001/04/30 11:18:52

[readconf.c readconf.h ssh.1 ssh.c sshconnect.c]
     implement 'ssh -b bind_address' like 'telnet -b'

ChangeLog

@@ -1,3 +1,9 @@
+20010501
+ - OpenBSD CVS Sync
+   - markus@cvs.openbsd.org 2001/04/30 11:18:52
+     [readconf.c readconf.h ssh.1 ssh.c sshconnect.c]
+     implement 'ssh -b bind_address' like 'telnet -b'
+
 20010430
  - OpenBSD CVS Sync
    - markus@cvs.openbsd.org 2001/04/29 18:32:52
@@ -5282,4 +5288,4 @@
  - Wrote replacements for strlcpy and mkdtemp
  - Released 1.0pre1
 
-$Id: ChangeLog,v 1.1184 2001/04/30 03:55:37 djm Exp $
+$Id: ChangeLog,v 1.1185 2001/04/30 13:06:24 mouring Exp $

readconf.c

@@ -12,7 +12,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: readconf.c,v 1.76 2001/04/17 10:53:25 markus Exp $");
+RCSID("$OpenBSD: readconf.c,v 1.77 2001/04/30 11:18:51 markus Exp $");
 
 #include "ssh.h"
 #include "xmalloc.h"
@@ -111,7 +111,7 @@ typedef enum {
 	oGlobalKnownHostsFile2, oUserKnownHostsFile2, oPubkeyAuthentication,
 	oKbdInteractiveAuthentication, oKbdInteractiveDevices, oHostKeyAlias,
 	oDynamicForward, oPreferredAuthentications, oHostbasedAuthentication,
-	oHostKeyAlgorithms
+	oHostKeyAlgorithms, oBindAddress
 } OpCodes;
 
 /* Textual representations of the tokens. */
@@ -177,6 +177,7 @@ static struct {
 	{ "dynamicforward", oDynamicForward },
 	{ "preferredauthentications", oPreferredAuthentications },
 	{ "hostkeyalgorithms", oHostKeyAlgorithms },
+	{ "bindaddress", oBindAddress },
 	{ NULL, 0 }
 };
 
@@ -459,6 +460,10 @@ parse_string:
 		charptr = &options->preferred_authentications;
 		goto parse_string;
 
+	case oBindAddress:
+		charptr = &options->bind_address;
+		goto parse_string;
+
 	case oProxyCommand:
 		charptr = &options->proxy_command;
 		string = xstrdup("");
@@ -761,6 +766,7 @@ initialize_options(Options * options)
 	options->num_remote_forwards = 0;
 	options->log_level = (LogLevel) - 1;
 	options->preferred_authentications = NULL;
+	options->bind_address = NULL;
 }
 
 /*

readconf.h

@@ -11,7 +11,7 @@
  * called by a name other than "ssh" or "Secure Shell".
  */
 
-/* RCSID("$OpenBSD: readconf.h,v 1.30 2001/04/17 10:53:25 markus Exp $"); */
+/* RCSID("$OpenBSD: readconf.h,v 1.31 2001/04/30 11:18:52 markus Exp $"); */
 
 #ifndef READCONF_H
 #define READCONF_H
@@ -85,6 +85,7 @@ typedef struct {
 	char   *system_hostfile2;
 	char   *user_hostfile2;
 	char   *preferred_authentications;
+	char   *bind_address;	/* local socket address for connection to sshd */
 
 	int     num_identity_files;	/* Number of files for RSA/DSA identities. */
 	char   *identity_files[SSH_MAX_IDENTITY_FILES];

ssh.1

@@ -34,7 +34,7 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.\" $OpenBSD: ssh.1,v 1.107 2001/04/22 23:58:36 markus Exp $
+.\" $OpenBSD: ssh.1,v 1.108 2001/04/30 11:18:52 markus Exp $
 .Dd September 25, 1999
 .Dt SSH 1
 .Os
@@ -49,6 +49,7 @@
 .Pp
 .Nm ssh
 .Op Fl afgknqstvxACNPTX1246
+.Op Fl b Ar bind_address
 .Op Fl c Ar cipher_spec
 .Op Fl e Ar escape_char
 .Op Fl i Ar identity_file
@@ -383,6 +384,9 @@ Disables forwarding of the authentication agent connection.
 .It Fl A
 Enables forwarding of the authentication agent connection.
 This can also be specified on a per-host basis in a configuration file.
+.It Fl b Ar bind_address
+Specify the interface to transmit from on machines with multiple
+interfaces or aliased addresses.
 .It Fl c Ar blowfish|3des
 Selects the cipher to use for encrypting the session.
 .Ar 3des
@@ -667,6 +671,13 @@ or
 .Dq no .
 The default is
 .Dq no .
+.It Cm BindAddress
+Specify the interface to transmit from on machines with multiple
+interfaces or aliased addresses.
+Note that this option does not work if
+.Cm UsePrivilegedPort
+is set to
+.Dq yes .
 .It Cm CheckHostIP
 If this flag is set to
 .Dq yes ,

ssh.c

@@ -39,7 +39,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: ssh.c,v 1.116 2001/04/17 12:55:04 markus Exp $");
+RCSID("$OpenBSD: ssh.c,v 1.117 2001/04/30 11:18:52 markus Exp $");
 
 #include <openssl/evp.h>
 #include <openssl/err.h>
@@ -191,6 +191,7 @@ usage(void)
 	fprintf(stderr, "  -6          Use IPv6 only.\n");
 	fprintf(stderr, "  -o 'option' Process the option as if it was read from a configuration file.\n");
 	fprintf(stderr, "  -s          Invoke command (mandatory) as SSH2 subsystem.\n");
+	fprintf(stderr, "  -b          Local IP address.\n");
 	exit(1);
 }
 
@@ -318,7 +319,7 @@ main(int ac, char **av)
 		opt = av[optind][1];
 		if (!opt)
 			usage();
-		if (strchr("eilcmpLRDo", opt)) {   /* options with arguments */
+		if (strchr("eilcmpbLRDo", opt)) {   /* options with arguments */
 			optarg = av[optind] + 2;
 			if (strcmp(optarg, "") == 0) {
 				if (optind >= ac - 1)
@@ -517,6 +518,9 @@ main(int ac, char **av)
 		case 's':
 			subsystem_flag = 1;
 			break;
+		case 'b':
+			options.bind_address = optarg;
+			break;
 		default:
 			usage();
 		}

sshconnect.c

@@ -13,7 +13,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect.c,v 1.104 2001/04/12 19:15:25 markus Exp $");
+RCSID("$OpenBSD: sshconnect.c,v 1.105 2001/04/30 11:18:52 markus Exp $");
 
 #include <openssl/bn.h>
 
@@ -147,7 +147,8 @@ ssh_proxy_connect(const char *host, u_short port, struct passwd *pw,
 int
 ssh_create_socket(struct passwd *pw, int privileged, int family)
 {
-	int sock;
+	int sock, gaierr;
+	struct addrinfo hints, *res;
 
 	/*
 	 * If we are running as root and want to connect to a privileged
@@ -160,7 +161,8 @@ ssh_create_socket(struct passwd *pw, int privileged, int family)
 			error("rresvport: af=%d %.100s", family, strerror(errno));
 		else
 			debug("Allocated local port %d.", p);
-	} else {
+		return sock;
+	}
 	/*
 	 * Just create an ordinary socket on arbitrary port.  We use
 	 * the user's uid to create the socket.
@@ -170,7 +172,29 @@ ssh_create_socket(struct passwd *pw, int privileged, int family)
 	if (sock < 0)
 		error("socket: %.100s", strerror(errno));
 	restore_uid();
+
+	/* Bind the socket to an alternative local IP address */
+	if (options.bind_address == NULL)
+		return sock;
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = IPv4or6;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_PASSIVE;
+	gaierr = getaddrinfo(options.bind_address, "0", &hints, &res);
+	if (gaierr) {
+		error("getaddrinfo: %s: %s", options.bind_address,
+		    gai_strerror(gaierr));
+		close(sock);
+		return -1;
 	}
+	if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
+		error("bind: %s: %s", options.bind_address, strerror(errno));
+		close(sock);
+		freeaddrinfo(res);
+		return -1;
+	}
+	freeaddrinfo(res);
 	return sock;
 }