blob: a604c9724aa0512f2b7732ab509c1142364fd6dc [file] [log] [blame]
Darren Tucker4abde772007-12-29 02:43:51 +11001/* $OpenBSD: sshconnect.c,v 1.203 2007/12/27 14:22:08 dtucker Exp $ */
Damien Millerd4a8b7e1999-10-27 13:42:43 +10002/*
Damien Miller95def091999-11-25 00:26:21 +11003 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * All rights reserved
Damien Miller95def091999-11-25 00:26:21 +11006 * Code to connect to a remote host, and to perform the client side of the
7 * login (authentication) dialog.
Damien Millere4340be2000-09-16 13:29:08 +11008 *
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
Damien Miller95def091999-11-25 00:26:21 +110014 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100015
16#include "includes.h"
Damien Miller9cf6d072006-03-15 11:29:24 +110017
18#include <sys/types.h>
19#include <sys/wait.h>
Damien Millerf17883e2006-03-15 11:45:54 +110020#include <sys/stat.h>
Damien Miller8ec8c3e2006-07-10 20:35:38 +100021#include <sys/socket.h>
Damien Miller9aec9192006-08-05 10:57:45 +100022#ifdef HAVE_SYS_TIME_H
23# include <sys/time.h>
24#endif
Damien Miller8ec8c3e2006-07-10 20:35:38 +100025
26#include <netinet/in.h>
Darren Tucker46aa3e02006-09-02 15:32:40 +100027#include <arpa/inet.h>
Damien Miller03e20032006-03-15 11:16:59 +110028
Damien Millerc7b06362006-03-15 11:53:45 +110029#include <ctype.h>
Darren Tucker39972492006-07-12 22:22:46 +100030#include <errno.h>
Damien Millerb8fe89c2006-07-24 14:51:00 +100031#include <netdb.h>
Damien Miller6645e7a2006-03-15 14:42:54 +110032#ifdef HAVE_PATHS_H
Damien Miller03e20032006-03-15 11:16:59 +110033#include <paths.h>
Damien Miller6645e7a2006-03-15 14:42:54 +110034#endif
Damien Miller9f2abc42006-07-10 20:53:08 +100035#include <pwd.h>
Damien Millerded319c2006-09-01 15:38:36 +100036#include <stdarg.h>
Damien Millera7a73ee2006-08-05 11:37:59 +100037#include <stdio.h>
Damien Millere7a1e5c2006-08-05 11:34:19 +100038#include <stdlib.h>
Damien Millere3476ed2006-07-24 14:13:33 +100039#include <string.h>
Damien Millere6b3b612006-07-24 14:01:23 +100040#include <unistd.h>
Damien Millerd4a8b7e1999-10-27 13:42:43 +100041
Damien Millerd4a8b7e1999-10-27 13:42:43 +100042#include "xmalloc.h"
Damien Millerd7834352006-08-05 12:39:39 +100043#include "key.h"
44#include "hostfile.h"
45#include "ssh.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100046#include "rsa.h"
Damien Miller1383bd82000-04-06 12:32:37 +100047#include "buffer.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100048#include "packet.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100049#include "uidswap.h"
50#include "compat.h"
Damien Miller450a7a12000-03-26 13:04:51 +100051#include "key.h"
Damien Millereba71ba2000-04-29 23:57:08 +100052#include "sshconnect.h"
Damien Miller450a7a12000-03-26 13:04:51 +100053#include "hostfile.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000054#include "log.h"
55#include "readconf.h"
56#include "atomicio.h"
57#include "misc.h"
Damien Miller37876e92003-05-15 10:19:46 +100058#include "dns.h"
Damien Millerb7576772006-07-10 20:23:39 +100059#include "version.h"
Damien Miller37876e92003-05-15 10:19:46 +100060
Damien Millereba71ba2000-04-29 23:57:08 +100061char *client_version_string = NULL;
62char *server_version_string = NULL;
Damien Miller1383bd82000-04-06 12:32:37 +100063
Damien Millerc1af1d52005-11-05 15:08:57 +110064static int matching_host_key_dns = 0;
Damien Miller7392ae62003-06-11 22:05:25 +100065
Ben Lindstromf9c48842002-06-11 16:37:51 +000066/* import */
Damien Milleraae6c611999-12-06 11:47:28 +110067extern Options options;
Damien Miller34132e52000-01-14 15:45:46 +110068extern char *__progname;
Ben Lindstromf9c48842002-06-11 16:37:51 +000069extern uid_t original_real_uid;
70extern uid_t original_effective_uid;
Damien Miller8c4e18a2002-09-19 12:05:02 +100071extern pid_t proxy_command_pid;
Damien Milleraae6c611999-12-06 11:47:28 +110072
Tim Ricee991e3c2001-08-07 15:29:07 -070073#ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */
74#define INET6_ADDRSTRLEN 46
75#endif
76
Ben Lindstrom3ed66402002-08-01 01:21:56 +000077static int show_other_keys(const char *, Key *);
Damien Miller5a388972003-11-17 21:10:47 +110078static void warn_changed_key(Key *);
Ben Lindstrom3ed66402002-08-01 01:21:56 +000079
Damien Miller67bd0622007-09-17 12:06:57 +100080static void
81ms_subtract_diff(struct timeval *start, int *ms)
82{
83 struct timeval diff, finish;
84
85 gettimeofday(&finish, NULL);
86 timersub(&finish, start, &diff);
87 *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000);
88}
89
90static void
91ms_to_timeval(struct timeval *tv, int ms)
92{
93 tv->tv_sec = ms / 1000;
94 tv->tv_usec = (ms % 1000) * 1000;
95}
96
Damien Miller95def091999-11-25 00:26:21 +110097/*
98 * Connect to the given ssh server using a proxy command.
99 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000100static int
Ben Lindstromf9c48842002-06-11 16:37:51 +0000101ssh_proxy_connect(const char *host, u_short port, const char *proxy_command)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000102{
Damien Miller6476cad2005-06-16 13:18:34 +1000103 char *command_string, *tmp;
Damien Miller95def091999-11-25 00:26:21 +1100104 int pin[2], pout[2];
Damien Miller166fca82000-04-20 07:42:21 +1000105 pid_t pid;
Damien Miller1d824ab2007-09-17 11:58:04 +1000106 char *shell, strport[NI_MAXSERV];
107
108 if ((shell = getenv("SHELL")) == NULL)
109 shell = _PATH_BSHELL;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000110
Damien Miller95def091999-11-25 00:26:21 +1100111 /* Convert the port number into a string. */
Damien Miller34132e52000-01-14 15:45:46 +1100112 snprintf(strport, sizeof strport, "%hu", port);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000113
Damien Miller8c4e18a2002-09-19 12:05:02 +1000114 /*
115 * Build the final command string in the buffer by making the
116 * appropriate substitutions to the given proxy command.
117 *
Damien Millera8e06ce2003-11-21 23:48:55 +1100118 * Use "exec" to avoid "sh -c" processes on some platforms
Damien Miller8c4e18a2002-09-19 12:05:02 +1000119 * (e.g. Solaris)
120 */
Damien Miller07d86be2006-03-26 14:19:21 +1100121 xasprintf(&tmp, "exec %s", proxy_command);
Damien Miller6476cad2005-06-16 13:18:34 +1000122 command_string = percent_expand(tmp, "h", host,
123 "p", strport, (char *)NULL);
124 xfree(tmp);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000125
Damien Miller95def091999-11-25 00:26:21 +1100126 /* Create pipes for communicating with the proxy. */
127 if (pipe(pin) < 0 || pipe(pout) < 0)
128 fatal("Could not create pipes to communicate with the proxy: %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +1100129 strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000130
Damien Miller95def091999-11-25 00:26:21 +1100131 debug("Executing proxy command: %.500s", command_string);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000132
Damien Miller95def091999-11-25 00:26:21 +1100133 /* Fork and execute the proxy command. */
134 if ((pid = fork()) == 0) {
135 char *argv[10];
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000136
Damien Miller95def091999-11-25 00:26:21 +1100137 /* Child. Permanently give up superuser privileges. */
Damien Miller2e5fe882006-06-13 13:10:00 +1000138 permanently_drop_suid(original_real_uid);
Damien Miller95def091999-11-25 00:26:21 +1100139
140 /* Redirect stdin and stdout. */
141 close(pin[1]);
142 if (pin[0] != 0) {
143 if (dup2(pin[0], 0) < 0)
144 perror("dup2 stdin");
145 close(pin[0]);
146 }
147 close(pout[0]);
148 if (dup2(pout[1], 1) < 0)
149 perror("dup2 stdout");
150 /* Cannot be 1 because pin allocated two descriptors. */
151 close(pout[1]);
152
153 /* Stderr is left as it is so that error messages get
154 printed on the user's terminal. */
Damien Miller1d824ab2007-09-17 11:58:04 +1000155 argv[0] = shell;
Damien Miller95def091999-11-25 00:26:21 +1100156 argv[1] = "-c";
157 argv[2] = command_string;
158 argv[3] = NULL;
159
160 /* Execute the proxy command. Note that we gave up any
161 extra privileges above. */
Kevin Stevesfcd5d602001-01-07 11:45:22 +0000162 execv(argv[0], argv);
163 perror(argv[0]);
Damien Miller95def091999-11-25 00:26:21 +1100164 exit(1);
165 }
166 /* Parent. */
167 if (pid < 0)
168 fatal("fork failed: %.100s", strerror(errno));
Damien Miller8c4e18a2002-09-19 12:05:02 +1000169 else
170 proxy_command_pid = pid; /* save pid to clean up later */
Damien Miller95def091999-11-25 00:26:21 +1100171
172 /* Close child side of the descriptors. */
173 close(pin[0]);
174 close(pout[1]);
175
176 /* Free the command name. */
Damien Miller6476cad2005-06-16 13:18:34 +1000177 xfree(command_string);
Damien Miller95def091999-11-25 00:26:21 +1100178
179 /* Set the connection file descriptors. */
180 packet_set_connection(pout[0], pin[1]);
181
Ben Lindstromf9cedb92001-08-06 21:07:11 +0000182 /* Indicate OK return */
183 return 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000184}
185
Damien Miller95def091999-11-25 00:26:21 +1100186/*
187 * Creates a (possibly privileged) socket for use as the ssh connection.
188 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000189static int
Damien Miller2372ace2003-05-14 13:42:23 +1000190ssh_create_socket(int privileged, struct addrinfo *ai)
Damien Miller95def091999-11-25 00:26:21 +1100191{
Ben Lindstrome0f88042001-04-30 13:06:24 +0000192 int sock, gaierr;
193 struct addrinfo hints, *res;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000194
Damien Miller5428f641999-11-25 11:54:57 +1100195 /*
196 * If we are running as root and want to connect to a privileged
197 * port, bind our own socket to a privileged port.
198 */
Damien Miller95def091999-11-25 00:26:21 +1100199 if (privileged) {
200 int p = IPPORT_RESERVED - 1;
Ben Lindstromf9c48842002-06-11 16:37:51 +0000201 PRIV_START;
Damien Miller2372ace2003-05-14 13:42:23 +1000202 sock = rresvport_af(&p, ai->ai_family);
Ben Lindstromf9c48842002-06-11 16:37:51 +0000203 PRIV_END;
Damien Miller95def091999-11-25 00:26:21 +1100204 if (sock < 0)
Damien Miller2372ace2003-05-14 13:42:23 +1000205 error("rresvport: af=%d %.100s", ai->ai_family,
206 strerror(errno));
Damien Miller98c7ad62000-03-09 21:27:49 +1100207 else
208 debug("Allocated local port %d.", p);
Ben Lindstrome0f88042001-04-30 13:06:24 +0000209 return sock;
Damien Miller95def091999-11-25 00:26:21 +1100210 }
Damien Miller2372ace2003-05-14 13:42:23 +1000211 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
Ben Lindstrome0f88042001-04-30 13:06:24 +0000212 if (sock < 0)
213 error("socket: %.100s", strerror(errno));
Ben Lindstrome0f88042001-04-30 13:06:24 +0000214
215 /* Bind the socket to an alternative local IP address */
216 if (options.bind_address == NULL)
217 return sock;
218
219 memset(&hints, 0, sizeof(hints));
Damien Miller2372ace2003-05-14 13:42:23 +1000220 hints.ai_family = ai->ai_family;
221 hints.ai_socktype = ai->ai_socktype;
222 hints.ai_protocol = ai->ai_protocol;
Ben Lindstrome0f88042001-04-30 13:06:24 +0000223 hints.ai_flags = AI_PASSIVE;
224 gaierr = getaddrinfo(options.bind_address, "0", &hints, &res);
225 if (gaierr) {
226 error("getaddrinfo: %s: %s", options.bind_address,
Darren Tucker4abde772007-12-29 02:43:51 +1100227 ssh_gai_strerror(gaierr));
Ben Lindstrome0f88042001-04-30 13:06:24 +0000228 close(sock);
229 return -1;
230 }
231 if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
232 error("bind: %s: %s", options.bind_address, strerror(errno));
233 close(sock);
234 freeaddrinfo(res);
235 return -1;
236 }
237 freeaddrinfo(res);
Damien Miller95def091999-11-25 00:26:21 +1100238 return sock;
239}
240
Damien Millerb78d5eb2003-05-16 11:39:04 +1000241static int
242timeout_connect(int sockfd, const struct sockaddr *serv_addr,
Damien Miller67bd0622007-09-17 12:06:57 +1000243 socklen_t addrlen, int *timeoutp)
Damien Millerb78d5eb2003-05-16 11:39:04 +1000244{
245 fd_set *fdset;
Damien Miller67bd0622007-09-17 12:06:57 +1000246 struct timeval tv, t_start;
Damien Millerb78d5eb2003-05-16 11:39:04 +1000247 socklen_t optlen;
Damien Miller07d86be2006-03-26 14:19:21 +1100248 int optval, rc, result = -1;
Damien Millerb78d5eb2003-05-16 11:39:04 +1000249
Damien Miller67bd0622007-09-17 12:06:57 +1000250 gettimeofday(&t_start, NULL);
251
252 if (*timeoutp <= 0) {
253 result = connect(sockfd, serv_addr, addrlen);
254 goto done;
255 }
Damien Millerb78d5eb2003-05-16 11:39:04 +1000256
Damien Millerf6723f02004-01-27 21:21:27 +1100257 set_nonblock(sockfd);
Damien Millerb78d5eb2003-05-16 11:39:04 +1000258 rc = connect(sockfd, serv_addr, addrlen);
Damien Millerf6723f02004-01-27 21:21:27 +1100259 if (rc == 0) {
260 unset_nonblock(sockfd);
Damien Miller67bd0622007-09-17 12:06:57 +1000261 result = 0;
262 goto done;
Damien Millerf6723f02004-01-27 21:21:27 +1100263 }
Damien Miller67bd0622007-09-17 12:06:57 +1000264 if (errno != EINPROGRESS) {
265 result = -1;
266 goto done;
267 }
Damien Millerb78d5eb2003-05-16 11:39:04 +1000268
Damien Miller07d86be2006-03-26 14:19:21 +1100269 fdset = (fd_set *)xcalloc(howmany(sockfd + 1, NFDBITS),
270 sizeof(fd_mask));
Damien Millerb78d5eb2003-05-16 11:39:04 +1000271 FD_SET(sockfd, fdset);
Damien Miller67bd0622007-09-17 12:06:57 +1000272 ms_to_timeval(&tv, *timeoutp);
Damien Millerb78d5eb2003-05-16 11:39:04 +1000273
Darren Tucker47eede72005-03-14 23:08:12 +1100274 for (;;) {
Damien Millerb78d5eb2003-05-16 11:39:04 +1000275 rc = select(sockfd + 1, NULL, fdset, NULL, &tv);
276 if (rc != -1 || errno != EINTR)
277 break;
278 }
279
Darren Tucker47eede72005-03-14 23:08:12 +1100280 switch (rc) {
Damien Millerb78d5eb2003-05-16 11:39:04 +1000281 case 0:
282 /* Timed out */
283 errno = ETIMEDOUT;
Damien Miller08293fa2003-05-23 18:44:41 +1000284 break;
Damien Millerb78d5eb2003-05-16 11:39:04 +1000285 case -1:
286 /* Select error */
Damien Millera8e06ce2003-11-21 23:48:55 +1100287 debug("select: %s", strerror(errno));
Damien Miller08293fa2003-05-23 18:44:41 +1000288 break;
Damien Millerb78d5eb2003-05-16 11:39:04 +1000289 case 1:
290 /* Completed or failed */
291 optval = 0;
292 optlen = sizeof(optval);
Damien Millera8e06ce2003-11-21 23:48:55 +1100293 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval,
Darren Tuckerbd5361b2003-09-22 20:59:16 +1000294 &optlen) == -1) {
Damien Millera8e06ce2003-11-21 23:48:55 +1100295 debug("getsockopt: %s", strerror(errno));
Damien Miller08293fa2003-05-23 18:44:41 +1000296 break;
Darren Tuckerbd5361b2003-09-22 20:59:16 +1000297 }
Damien Millerb78d5eb2003-05-16 11:39:04 +1000298 if (optval != 0) {
299 errno = optval;
Damien Miller08293fa2003-05-23 18:44:41 +1000300 break;
Damien Millerb78d5eb2003-05-16 11:39:04 +1000301 }
Damien Miller08293fa2003-05-23 18:44:41 +1000302 result = 0;
Damien Millerf6723f02004-01-27 21:21:27 +1100303 unset_nonblock(sockfd);
Damien Millerb78d5eb2003-05-16 11:39:04 +1000304 break;
305 default:
306 /* Should not occur */
307 fatal("Bogus return (%d) from select()", rc);
308 }
309
Damien Miller08293fa2003-05-23 18:44:41 +1000310 xfree(fdset);
Damien Miller67bd0622007-09-17 12:06:57 +1000311
312 done:
313 if (result == 0 && *timeoutp > 0) {
314 ms_subtract_diff(&t_start, timeoutp);
315 if (*timeoutp <= 0) {
316 errno = ETIMEDOUT;
317 result = -1;
318 }
319 }
320
Damien Miller08293fa2003-05-23 18:44:41 +1000321 return (result);
Damien Millerb78d5eb2003-05-16 11:39:04 +1000322}
323
Damien Miller95def091999-11-25 00:26:21 +1100324/*
Damien Miller34132e52000-01-14 15:45:46 +1100325 * Opens a TCP/IP connection to the remote server on the given host.
326 * The address of the remote host will be returned in hostaddr.
Ben Lindstromf9c48842002-06-11 16:37:51 +0000327 * If port is 0, the default port will be used. If needpriv is true,
Damien Miller95def091999-11-25 00:26:21 +1100328 * a privileged port will be allocated to make the connection.
Ben Lindstromf9c48842002-06-11 16:37:51 +0000329 * This requires super-user privileges if needpriv is true.
Damien Miller95def091999-11-25 00:26:21 +1100330 * Connection_attempts specifies the maximum number of tries (one per
331 * second). If proxy_command is non-NULL, it specifies the command (with %h
332 * and %p substituted for host and port, respectively) to use to contact
333 * the daemon.
334 */
335int
Damien Miller34132e52000-01-14 15:45:46 +1100336ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
Damien Miller67bd0622007-09-17 12:06:57 +1000337 u_short port, int family, int connection_attempts, int *timeout_ms,
338 int want_keepalive, int needpriv, const char *proxy_command)
Damien Miller95def091999-11-25 00:26:21 +1100339{
Damien Miller34132e52000-01-14 15:45:46 +1100340 int gaierr;
Ben Lindstrombf555ba2001-01-18 02:04:35 +0000341 int on = 1;
342 int sock = -1, attempt;
343 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
344 struct addrinfo hints, *ai, *aitop;
Damien Miller95def091999-11-25 00:26:21 +1100345
Ben Lindstrom064496f2002-12-23 02:04:22 +0000346 debug2("ssh_connect: needpriv %d", needpriv);
Damien Miller95def091999-11-25 00:26:21 +1100347
Damien Miller95def091999-11-25 00:26:21 +1100348 /* If a proxy command is given, connect using it. */
349 if (proxy_command != NULL)
Ben Lindstromf9c48842002-06-11 16:37:51 +0000350 return ssh_proxy_connect(host, port, proxy_command);
Damien Miller95def091999-11-25 00:26:21 +1100351
352 /* No proxy command. */
353
Damien Miller34132e52000-01-14 15:45:46 +1100354 memset(&hints, 0, sizeof(hints));
Damien Miller139d4cd2001-10-10 15:07:44 +1000355 hints.ai_family = family;
Damien Miller34132e52000-01-14 15:45:46 +1100356 hints.ai_socktype = SOCK_STREAM;
Ben Lindstrom5c385522002-06-23 21:23:20 +0000357 snprintf(strport, sizeof strport, "%u", port);
Damien Miller34132e52000-01-14 15:45:46 +1100358 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
Darren Tucker4abde772007-12-29 02:43:51 +1100359 fatal("%s: Could not resolve hostname %.100s: %s", __progname,
360 host, ssh_gai_strerror(gaierr));
Damien Miller95def091999-11-25 00:26:21 +1100361
Damien Miller56e5e6a2006-04-23 12:08:59 +1000362 for (attempt = 0; attempt < connection_attempts; attempt++) {
Damien Millerf4bcd102006-10-24 03:02:23 +1000363 if (attempt > 0) {
364 /* Sleep a moment before retrying. */
365 sleep(1);
Damien Miller95def091999-11-25 00:26:21 +1100366 debug("Trying again...");
Damien Millerf4bcd102006-10-24 03:02:23 +1000367 }
Damien Miller56e5e6a2006-04-23 12:08:59 +1000368 /*
369 * Loop through addresses for this host, and try each one in
370 * sequence until the connection succeeds.
371 */
Damien Miller34132e52000-01-14 15:45:46 +1100372 for (ai = aitop; ai; ai = ai->ai_next) {
373 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
374 continue;
375 if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
376 ntop, sizeof(ntop), strport, sizeof(strport),
377 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
378 error("ssh_connect: getnameinfo failed");
379 continue;
380 }
381 debug("Connecting to %.200s [%.100s] port %s.",
382 host, ntop, strport);
Damien Miller95def091999-11-25 00:26:21 +1100383
Damien Miller34132e52000-01-14 15:45:46 +1100384 /* Create a socket for connecting. */
Damien Miller2372ace2003-05-14 13:42:23 +1000385 sock = ssh_create_socket(needpriv, ai);
Damien Miller34132e52000-01-14 15:45:46 +1100386 if (sock < 0)
Ben Lindstromf9cedb92001-08-06 21:07:11 +0000387 /* Any error is already output */
Damien Miller34132e52000-01-14 15:45:46 +1100388 continue;
Damien Miller95def091999-11-25 00:26:21 +1100389
Damien Millerb78d5eb2003-05-16 11:39:04 +1000390 if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen,
Damien Miller67bd0622007-09-17 12:06:57 +1000391 timeout_ms) >= 0) {
Damien Miller34132e52000-01-14 15:45:46 +1100392 /* Successful connection. */
Ben Lindstroma3700052001-04-05 23:26:32 +0000393 memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
Damien Miller95def091999-11-25 00:26:21 +1100394 break;
Damien Miller34132e52000-01-14 15:45:46 +1100395 } else {
Ben Lindstrom728aa7e2002-07-15 17:48:11 +0000396 debug("connect to address %s port %s: %s",
397 ntop, strport, strerror(errno));
Damien Miller95def091999-11-25 00:26:21 +1100398 close(sock);
Damien Miller56e5e6a2006-04-23 12:08:59 +1000399 sock = -1;
Damien Miller95def091999-11-25 00:26:21 +1100400 }
Damien Miller95def091999-11-25 00:26:21 +1100401 }
Damien Miller56e5e6a2006-04-23 12:08:59 +1000402 if (sock != -1)
Damien Miller34132e52000-01-14 15:45:46 +1100403 break; /* Successful connection. */
Damien Miller95def091999-11-25 00:26:21 +1100404 }
Damien Miller34132e52000-01-14 15:45:46 +1100405
406 freeaddrinfo(aitop);
407
Damien Miller95def091999-11-25 00:26:21 +1100408 /* Return failure if we didn't get a successful connection. */
Damien Miller56e5e6a2006-04-23 12:08:59 +1000409 if (sock == -1) {
Darren Tuckerb2161e32005-01-20 11:00:46 +1100410 error("ssh: connect to host %s port %s: %s",
Ben Lindstroma6cd75c2002-07-11 04:00:19 +0000411 host, strport, strerror(errno));
Darren Tuckerb2161e32005-01-20 11:00:46 +1100412 return (-1);
Ben Lindstroma6cd75c2002-07-11 04:00:19 +0000413 }
Damien Miller95def091999-11-25 00:26:21 +1100414
415 debug("Connection established.");
416
Damien Miller12c150e2003-12-17 16:31:10 +1100417 /* Set SO_KEEPALIVE if requested. */
Damien Miller67bd0622007-09-17 12:06:57 +1000418 if (want_keepalive &&
Ben Lindstrombf555ba2001-01-18 02:04:35 +0000419 setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
420 sizeof(on)) < 0)
421 error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
Damien Miller95def091999-11-25 00:26:21 +1100422
423 /* Set the connection. */
424 packet_set_connection(sock, sock);
425
Ben Lindstromf9cedb92001-08-06 21:07:11 +0000426 return 0;
Damien Miller95def091999-11-25 00:26:21 +1100427}
428
Damien Milleraae6c611999-12-06 11:47:28 +1100429/*
Damien Miller95def091999-11-25 00:26:21 +1100430 * Waits for the server identification string, and sends our own
431 * identification string.
432 */
Ben Lindstrombba81212001-06-25 05:01:22 +0000433static void
Damien Miller67bd0622007-09-17 12:06:57 +1000434ssh_exchange_identification(int timeout_ms)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000435{
Damien Miller95def091999-11-25 00:26:21 +1100436 char buf[256], remote_version[256]; /* must be same size! */
Damien Millereccb9de2005-06-17 12:59:34 +1000437 int remote_major, remote_minor, mismatch;
Damien Miller95def091999-11-25 00:26:21 +1100438 int connection_in = packet_get_connection_in();
439 int connection_out = packet_get_connection_out();
Kevin Stevesef4eea92001-02-05 12:42:17 +0000440 int minor1 = PROTOCOL_MINOR_1;
Damien Miller1e88ea62006-07-10 20:15:56 +1000441 u_int i, n;
Damien Miller67bd0622007-09-17 12:06:57 +1000442 size_t len;
443 int fdsetsz, remaining, rc;
444 struct timeval t_start, t_remaining;
445 fd_set *fdset;
446
447 fdsetsz = howmany(connection_in + 1, NFDBITS) * sizeof(fd_mask);
448 fdset = xcalloc(1, fdsetsz);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000449
Damien Millerb253cc42005-05-26 12:23:44 +1000450 /* Read other side's version identification. */
Damien Miller67bd0622007-09-17 12:06:57 +1000451 remaining = timeout_ms;
Damien Miller1e88ea62006-07-10 20:15:56 +1000452 for (n = 0;;) {
Damien Millerf6d9e222000-06-18 14:50:44 +1000453 for (i = 0; i < sizeof(buf) - 1; i++) {
Damien Miller67bd0622007-09-17 12:06:57 +1000454 if (timeout_ms > 0) {
455 gettimeofday(&t_start, NULL);
456 ms_to_timeval(&t_remaining, remaining);
457 FD_SET(connection_in, fdset);
458 rc = select(connection_in + 1, fdset, NULL,
459 fdset, &t_remaining);
460 ms_subtract_diff(&t_start, &remaining);
461 if (rc == 0 || remaining <= 0)
462 fatal("Connection timed out during "
463 "banner exchange");
464 if (rc == -1) {
465 if (errno == EINTR)
466 continue;
467 fatal("ssh_exchange_identification: "
468 "select: %s", strerror(errno));
469 }
470 }
471
472 len = atomicio(read, connection_in, &buf[i], 1);
Damien Millerb253cc42005-05-26 12:23:44 +1000473
Damien Miller46d38de2005-07-17 17:02:09 +1000474 if (len != 1 && errno == EPIPE)
Damien Miller67bd0622007-09-17 12:06:57 +1000475 fatal("ssh_exchange_identification: "
476 "Connection closed by remote host");
Damien Millerb253cc42005-05-26 12:23:44 +1000477 else if (len != 1)
Damien Miller67bd0622007-09-17 12:06:57 +1000478 fatal("ssh_exchange_identification: "
479 "read: %.100s", strerror(errno));
Damien Millerf6d9e222000-06-18 14:50:44 +1000480 if (buf[i] == '\r') {
481 buf[i] = '\n';
482 buf[i + 1] = 0;
483 continue; /**XXX wait for \n */
484 }
485 if (buf[i] == '\n') {
486 buf[i + 1] = 0;
487 break;
488 }
Damien Miller1e88ea62006-07-10 20:15:56 +1000489 if (++n > 65536)
Damien Miller67bd0622007-09-17 12:06:57 +1000490 fatal("ssh_exchange_identification: "
491 "No banner received");
Damien Miller95def091999-11-25 00:26:21 +1100492 }
Damien Millerf6d9e222000-06-18 14:50:44 +1000493 buf[sizeof(buf) - 1] = 0;
494 if (strncmp(buf, "SSH-", 4) == 0)
Damien Miller95def091999-11-25 00:26:21 +1100495 break;
Damien Millerf6d9e222000-06-18 14:50:44 +1000496 debug("ssh_exchange_identification: %s", buf);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000497 }
Damien Miller1383bd82000-04-06 12:32:37 +1000498 server_version_string = xstrdup(buf);
Damien Miller67bd0622007-09-17 12:06:57 +1000499 xfree(fdset);
Damien Miller95def091999-11-25 00:26:21 +1100500
Damien Miller5428f641999-11-25 11:54:57 +1100501 /*
502 * Check that the versions match. In future this might accept
503 * several versions and set appropriate flags to handle them.
504 */
Damien Miller1383bd82000-04-06 12:32:37 +1000505 if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
506 &remote_major, &remote_minor, remote_version) != 3)
Damien Miller95def091999-11-25 00:26:21 +1100507 fatal("Bad remote protocol version identification: '%.100s'", buf);
508 debug("Remote protocol version %d.%d, remote software version %.100s",
Damien Miller9f0f5c62001-12-21 14:45:46 +1100509 remote_major, remote_minor, remote_version);
Damien Miller95def091999-11-25 00:26:21 +1100510
Damien Miller1383bd82000-04-06 12:32:37 +1000511 compat_datafellows(remote_version);
Damien Miller78928792000-04-12 20:17:38 +1000512 mismatch = 0;
Damien Miller1383bd82000-04-06 12:32:37 +1000513
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +0000514 switch (remote_major) {
Damien Miller78928792000-04-12 20:17:38 +1000515 case 1:
516 if (remote_minor == 99 &&
517 (options.protocol & SSH_PROTO_2) &&
518 !(options.protocol & SSH_PROTO_1_PREFERRED)) {
519 enable_compat20();
520 break;
Damien Miller95def091999-11-25 00:26:21 +1100521 }
Damien Miller78928792000-04-12 20:17:38 +1000522 if (!(options.protocol & SSH_PROTO_1)) {
523 mismatch = 1;
524 break;
525 }
526 if (remote_minor < 3) {
527 fatal("Remote machine has too old SSH software version.");
Damien Miller0bc1bd82000-11-13 22:57:25 +1100528 } else if (remote_minor == 3 || remote_minor == 4) {
Damien Miller78928792000-04-12 20:17:38 +1000529 /* We speak 1.3, too. */
530 enable_compat13();
Damien Miller0bc1bd82000-11-13 22:57:25 +1100531 minor1 = 3;
Damien Miller78928792000-04-12 20:17:38 +1000532 if (options.forward_agent) {
Damien Miller996acd22003-04-09 20:59:48 +1000533 logit("Agent forwarding disabled for protocol 1.3");
Damien Miller78928792000-04-12 20:17:38 +1000534 options.forward_agent = 0;
535 }
536 }
537 break;
538 case 2:
539 if (options.protocol & SSH_PROTO_2) {
540 enable_compat20();
541 break;
542 }
543 /* FALLTHROUGH */
Damien Miller4af51302000-04-16 11:18:38 +1000544 default:
Damien Miller78928792000-04-12 20:17:38 +1000545 mismatch = 1;
546 break;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000547 }
Damien Miller78928792000-04-12 20:17:38 +1000548 if (mismatch)
Damien Miller95def091999-11-25 00:26:21 +1100549 fatal("Protocol major versions differ: %d vs. %d",
Damien Miller78928792000-04-12 20:17:38 +1000550 (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
551 remote_major);
Damien Miller95def091999-11-25 00:26:21 +1100552 /* Send our own protocol version identification. */
553 snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
Damien Miller78928792000-04-12 20:17:38 +1000554 compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
Damien Miller0bc1bd82000-11-13 22:57:25 +1100555 compat20 ? PROTOCOL_MINOR_2 : minor1,
Damien Miller1383bd82000-04-06 12:32:37 +1000556 SSH_VERSION);
Darren Tucker9f63f222003-07-03 13:46:56 +1000557 if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf))
Damien Miller95def091999-11-25 00:26:21 +1100558 fatal("write: %.100s", strerror(errno));
Damien Miller1383bd82000-04-06 12:32:37 +1000559 client_version_string = xstrdup(buf);
560 chop(client_version_string);
561 chop(server_version_string);
562 debug("Local version string %.100s", client_version_string);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000563}
564
Ben Lindstromb6c06d92001-02-10 23:21:09 +0000565/* defaults to 'no' */
Ben Lindstrombba81212001-06-25 05:01:22 +0000566static int
Damien Millere3980042001-10-10 15:02:03 +1000567confirm(const char *prompt)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000568{
Damien Miller49d795c2002-01-22 23:34:12 +1100569 const char *msg, *again = "Please type 'yes' or 'no': ";
570 char *p;
571 int ret = -1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000572
Ben Lindstromb6c06d92001-02-10 23:21:09 +0000573 if (options.batch_mode)
574 return 0;
Damien Miller49d795c2002-01-22 23:34:12 +1100575 for (msg = prompt;;msg = again) {
576 p = read_passphrase(msg, RP_ECHO);
577 if (p == NULL ||
578 (p[0] == '\0') || (p[0] == '\n') ||
579 strncasecmp(p, "no", 2) == 0)
580 ret = 0;
Ben Lindstrom04f9af72002-07-04 00:03:56 +0000581 if (p && strncasecmp(p, "yes", 3) == 0)
Damien Miller49d795c2002-01-22 23:34:12 +1100582 ret = 1;
583 if (p)
584 xfree(p);
585 if (ret != -1)
586 return ret;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000587 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000588}
589
Damien Miller95def091999-11-25 00:26:21 +1100590/*
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000591 * check whether the supplied host key is valid, return -1 if the key
592 * is not valid. the user_hostfile will not be updated if 'readonly' is true.
Damien Miller95def091999-11-25 00:26:21 +1100593 */
Damien Millerda828392006-08-05 11:35:45 +1000594#define RDRW 0
595#define RDONLY 1
596#define ROQUIET 2
Ben Lindstrombba81212001-06-25 05:01:22 +0000597static int
Damien Millerda828392006-08-05 11:35:45 +1000598check_host_key(char *hostname, struct sockaddr *hostaddr, u_short port,
599 Key *host_key, int readonly, const char *user_hostfile,
600 const char *system_hostfile)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000601{
Damien Miller450a7a12000-03-26 13:04:51 +1000602 Key *file_key;
Damien Millerf58b58c2003-11-17 21:18:23 +1100603 const char *type = key_type(host_key);
Darren Tuckerda345532006-07-10 23:04:19 +1000604 char *ip = NULL, *host = NULL;
Ben Lindstromcfccef92001-03-13 04:57:58 +0000605 char hostline[1000], *hostp, *fp;
Damien Miller95def091999-11-25 00:26:21 +1100606 HostStatus host_status;
607 HostStatus ip_status;
Damien Miller1227d4c2005-03-02 12:06:51 +1100608 int r, local = 0, host_ip_differ = 0;
Damien Millereaf99942000-01-19 13:45:07 +1100609 int salen;
Damien Miller34132e52000-01-14 15:45:46 +1100610 char ntop[NI_MAXHOST];
Damien Miller49d795c2002-01-22 23:34:12 +1100611 char msg[1024];
Damien Miller7392ae62003-06-11 22:05:25 +1000612 int len, host_line, ip_line;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000613 const char *host_file = NULL, *ip_file = NULL;
Damien Miller34132e52000-01-14 15:45:46 +1100614
615 /*
616 * Force accepting of the host key for loopback/localhost. The
617 * problem is that if the home directory is NFS-mounted to multiple
618 * machines, localhost will refer to a different machine in each of
619 * them, and the user will get bogus HOST_CHANGED warnings. This
620 * essentially disables host authentication for localhost; however,
621 * this is probably not a real problem.
622 */
Damien Millereba71ba2000-04-29 23:57:08 +1000623 /** hostaddr == 0! */
Damien Miller34132e52000-01-14 15:45:46 +1100624 switch (hostaddr->sa_family) {
625 case AF_INET:
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000626 local = (ntohl(((struct sockaddr_in *)hostaddr)->
Damien Miller0dc1bef2005-07-17 17:22:45 +1000627 sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
Damien Millereaf99942000-01-19 13:45:07 +1100628 salen = sizeof(struct sockaddr_in);
Damien Miller34132e52000-01-14 15:45:46 +1100629 break;
630 case AF_INET6:
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000631 local = IN6_IS_ADDR_LOOPBACK(
632 &(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
Damien Millereaf99942000-01-19 13:45:07 +1100633 salen = sizeof(struct sockaddr_in6);
Damien Miller34132e52000-01-14 15:45:46 +1100634 break;
635 default:
636 local = 0;
Damien Millereaf99942000-01-19 13:45:07 +1100637 salen = sizeof(struct sockaddr_storage);
Damien Miller34132e52000-01-14 15:45:46 +1100638 break;
639 }
Ben Lindstrom3cecc9a2001-10-03 17:39:38 +0000640 if (options.no_host_authentication_for_localhost == 1 && local &&
641 options.host_key_alias == NULL) {
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000642 debug("Forcing accepting of host key for "
643 "loopback/localhost.");
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000644 return 0;
Damien Miller34132e52000-01-14 15:45:46 +1100645 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000646
Damien Milleraae6c611999-12-06 11:47:28 +1100647 /*
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000648 * We don't have the remote ip-address for connections
649 * using a proxy command
Damien Milleraae6c611999-12-06 11:47:28 +1100650 */
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000651 if (options.proxy_command == NULL) {
652 if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop),
653 NULL, 0, NI_NUMERICHOST) != 0)
654 fatal("check_host_key: getnameinfo failed");
Damien Millerda828392006-08-05 11:35:45 +1000655 ip = put_host_port(ntop, port);
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000656 } else {
657 ip = xstrdup("<no hostip for proxy command>");
658 }
659 /*
660 * Turn off check_host_ip if the connection is to localhost, via proxy
661 * command or if we don't have a hostname to compare with
662 */
Darren Tuckerda345532006-07-10 23:04:19 +1000663 if (options.check_host_ip && (local ||
664 strcmp(hostname, ip) == 0 || options.proxy_command != NULL))
Damien Milleraae6c611999-12-06 11:47:28 +1100665 options.check_host_ip = 0;
666
Damien Millera34a28b1999-12-14 10:47:15 +1100667 /*
Darren Tuckerda345532006-07-10 23:04:19 +1000668 * Allow the user to record the key under a different name or
669 * differentiate a non-standard port. This is useful for ssh
670 * tunneling over forwarded connections or if you run multiple
671 * sshd's on different ports on the same machine.
Ben Lindstrom4dccfa52000-12-28 16:40:05 +0000672 */
673 if (options.host_key_alias != NULL) {
Darren Tuckerda345532006-07-10 23:04:19 +1000674 host = xstrdup(options.host_key_alias);
Ben Lindstrom4dccfa52000-12-28 16:40:05 +0000675 debug("using hostkeyalias: %s", host);
Darren Tuckerda345532006-07-10 23:04:19 +1000676 } else {
Damien Millerda828392006-08-05 11:35:45 +1000677 host = put_host_port(hostname, port);
Ben Lindstrom4dccfa52000-12-28 16:40:05 +0000678 }
679
680 /*
Damien Millera34a28b1999-12-14 10:47:15 +1100681 * Store the host key from the known host file in here so that we can
682 * compare it with the key for the IP address.
683 */
Damien Miller450a7a12000-03-26 13:04:51 +1000684 file_key = key_new(host_key->type);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000685
Damien Miller5428f641999-11-25 11:54:57 +1100686 /*
Damien Miller788f2122005-11-05 15:14:59 +1100687 * Check if the host key is present in the user's list of known
Damien Miller5428f641999-11-25 11:54:57 +1100688 * hosts or in the systemwide list.
689 */
Ben Lindstrom46c16222000-12-22 01:43:59 +0000690 host_file = user_hostfile;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000691 host_status = check_host_in_hostfile(host_file, host, host_key,
Damien Miller9f0f5c62001-12-21 14:45:46 +1100692 file_key, &host_line);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000693 if (host_status == HOST_NEW) {
694 host_file = system_hostfile;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000695 host_status = check_host_in_hostfile(host_file, host, host_key,
696 file_key, &host_line);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000697 }
Damien Miller5428f641999-11-25 11:54:57 +1100698 /*
Damien Miller5428f641999-11-25 11:54:57 +1100699 * Also perform check for the ip address, skip the check if we are
700 * localhost or the hostname was an ip address to begin with
701 */
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000702 if (options.check_host_ip) {
Damien Miller450a7a12000-03-26 13:04:51 +1000703 Key *ip_key = key_new(host_key->type);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000704
Ben Lindstrom46c16222000-12-22 01:43:59 +0000705 ip_file = user_hostfile;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000706 ip_status = check_host_in_hostfile(ip_file, ip, host_key,
707 ip_key, &ip_line);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000708 if (ip_status == HOST_NEW) {
709 ip_file = system_hostfile;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000710 ip_status = check_host_in_hostfile(ip_file, ip,
711 host_key, ip_key, &ip_line);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000712 }
Damien Miller95def091999-11-25 00:26:21 +1100713 if (host_status == HOST_CHANGED &&
Damien Miller450a7a12000-03-26 13:04:51 +1000714 (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
Damien Miller95def091999-11-25 00:26:21 +1100715 host_ip_differ = 1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000716
Damien Miller450a7a12000-03-26 13:04:51 +1000717 key_free(ip_key);
Damien Miller95def091999-11-25 00:26:21 +1100718 } else
719 ip_status = host_status;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000720
Damien Miller450a7a12000-03-26 13:04:51 +1000721 key_free(file_key);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000722
Damien Miller95def091999-11-25 00:26:21 +1100723 switch (host_status) {
724 case HOST_OK:
725 /* The host is known and the key matches. */
Damien Millere247cc42000-05-07 12:03:14 +1000726 debug("Host '%.200s' is known and matches the %s host key.",
727 host, type);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000728 debug("Found key in %s:%d", host_file, host_line);
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000729 if (options.check_host_ip && ip_status == HOST_NEW) {
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000730 if (readonly)
Damien Miller996acd22003-04-09 20:59:48 +1000731 logit("%s host key for IP address "
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000732 "'%.128s' not in list of known hosts.",
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000733 type, ip);
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000734 else if (!add_host_to_hostfile(user_hostfile, ip,
Damien Millere1776152005-03-01 21:47:37 +1100735 host_key, options.hash_known_hosts))
Damien Miller996acd22003-04-09 20:59:48 +1000736 logit("Failed to add the %s host key for IP "
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000737 "address '%.128s' to the list of known "
738 "hosts (%.30s).", type, ip, user_hostfile);
739 else
Damien Miller996acd22003-04-09 20:59:48 +1000740 logit("Warning: Permanently added the %s host "
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000741 "key for IP address '%.128s' to the list "
742 "of known hosts.", type, ip);
Damien Miller95def091999-11-25 00:26:21 +1100743 }
744 break;
745 case HOST_NEW:
Damien Millerda828392006-08-05 11:35:45 +1000746 if (options.host_key_alias == NULL && port != 0 &&
747 port != SSH_DEFAULT_PORT) {
748 debug("checking without port identifier");
749 if (check_host_key(hostname, hostaddr, 0, host_key, 2,
750 user_hostfile, system_hostfile) == 0) {
751 debug("found matching key w/out port");
752 break;
753 }
754 }
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000755 if (readonly)
756 goto fail;
Damien Miller95def091999-11-25 00:26:21 +1100757 /* The host is new. */
758 if (options.strict_host_key_checking == 1) {
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000759 /*
760 * User has requested strict host key checking. We
761 * will not add the host key automatically. The only
762 * alternative left is to abort.
763 */
764 error("No %s host key is known for %.200s and you "
765 "have requested strict checking.", type, host);
766 goto fail;
Damien Miller95def091999-11-25 00:26:21 +1100767 } else if (options.strict_host_key_checking == 2) {
Damien Miller7392ae62003-06-11 22:05:25 +1000768 char msg1[1024], msg2[1024];
769
770 if (show_other_keys(host, host_key))
771 snprintf(msg1, sizeof(msg1),
Damien Miller0dc1bef2005-07-17 17:22:45 +1000772 "\nbut keys of different type are already"
773 " known for this host.");
Damien Miller7392ae62003-06-11 22:05:25 +1000774 else
775 snprintf(msg1, sizeof(msg1), ".");
Damien Miller95def091999-11-25 00:26:21 +1100776 /* The default */
Ben Lindstromcfccef92001-03-13 04:57:58 +0000777 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
Damien Miller7392ae62003-06-11 22:05:25 +1000778 msg2[0] = '\0';
Damien Miller7392ae62003-06-11 22:05:25 +1000779 if (options.verify_host_key_dns) {
Damien Miller150b5572003-11-17 21:19:29 +1100780 if (matching_host_key_dns)
Damien Miller7392ae62003-06-11 22:05:25 +1000781 snprintf(msg2, sizeof(msg2),
782 "Matching host key fingerprint"
783 " found in DNS.\n");
784 else
785 snprintf(msg2, sizeof(msg2),
786 "No matching host key fingerprint"
787 " found in DNS.\n");
788 }
Damien Miller49d795c2002-01-22 23:34:12 +1100789 snprintf(msg, sizeof(msg),
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000790 "The authenticity of host '%.200s (%s)' can't be "
Ben Lindstrom3ed66402002-08-01 01:21:56 +0000791 "established%s\n"
Damien Miller7392ae62003-06-11 22:05:25 +1000792 "%s key fingerprint is %s.\n%s"
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000793 "Are you sure you want to continue connecting "
Ben Lindstrom3ed66402002-08-01 01:21:56 +0000794 "(yes/no)? ",
Damien Miller7392ae62003-06-11 22:05:25 +1000795 host, ip, msg1, type, fp, msg2);
Ben Lindstromcfccef92001-03-13 04:57:58 +0000796 xfree(fp);
Damien Miller49d795c2002-01-22 23:34:12 +1100797 if (!confirm(msg))
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000798 goto fail;
Damien Miller95def091999-11-25 00:26:21 +1100799 }
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000800 /*
801 * If not in strict mode, add the key automatically to the
802 * local known_hosts file.
803 */
Damien Miller1227d4c2005-03-02 12:06:51 +1100804 if (options.check_host_ip && ip_status == HOST_NEW) {
805 snprintf(hostline, sizeof(hostline), "%s,%s",
806 host, ip);
807 hostp = hostline;
808 if (options.hash_known_hosts) {
809 /* Add hash of host and IP separately */
810 r = add_host_to_hostfile(user_hostfile, host,
811 host_key, options.hash_known_hosts) &&
812 add_host_to_hostfile(user_hostfile, ip,
813 host_key, options.hash_known_hosts);
814 } else {
815 /* Add unhashed "host,ip" */
816 r = add_host_to_hostfile(user_hostfile,
817 hostline, host_key,
818 options.hash_known_hosts);
819 }
820 } else {
821 r = add_host_to_hostfile(user_hostfile, host, host_key,
822 options.hash_known_hosts);
823 hostp = host;
824 }
825
826 if (!r)
Damien Miller996acd22003-04-09 20:59:48 +1000827 logit("Failed to add the host to the list of known "
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000828 "hosts (%.500s).", user_hostfile);
Damien Miller95def091999-11-25 00:26:21 +1100829 else
Damien Miller996acd22003-04-09 20:59:48 +1000830 logit("Warning: Permanently added '%.200s' (%s) to the "
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000831 "list of known hosts.", hostp, type);
Damien Miller95def091999-11-25 00:26:21 +1100832 break;
833 case HOST_CHANGED:
Damien Millerda828392006-08-05 11:35:45 +1000834 if (readonly == ROQUIET)
835 goto fail;
Damien Miller95def091999-11-25 00:26:21 +1100836 if (options.check_host_ip && host_ip_differ) {
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000837 char *key_msg;
Damien Miller95def091999-11-25 00:26:21 +1100838 if (ip_status == HOST_NEW)
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000839 key_msg = "is unknown";
Damien Miller95def091999-11-25 00:26:21 +1100840 else if (ip_status == HOST_OK)
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000841 key_msg = "is unchanged";
Damien Miller95def091999-11-25 00:26:21 +1100842 else
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000843 key_msg = "has a different value";
Damien Miller95def091999-11-25 00:26:21 +1100844 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
845 error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
846 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
Damien Millere247cc42000-05-07 12:03:14 +1000847 error("The %s host key for %s has changed,", type, host);
Damien Miller95def091999-11-25 00:26:21 +1100848 error("and the key for the according IP address %s", ip);
Darren Tucker3f9fdc72004-06-22 12:56:01 +1000849 error("%s. This could either mean that", key_msg);
Damien Miller95def091999-11-25 00:26:21 +1100850 error("DNS SPOOFING is happening or the IP address for the host");
Ben Lindstrom46c16222000-12-22 01:43:59 +0000851 error("and its host key have changed at the same time.");
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000852 if (ip_status != HOST_NEW)
Ben Lindstrom46c16222000-12-22 01:43:59 +0000853 error("Offending key for IP in %s:%d", ip_file, ip_line);
Damien Miller95def091999-11-25 00:26:21 +1100854 }
855 /* The host key has changed. */
Damien Miller5a388972003-11-17 21:10:47 +1100856 warn_changed_key(host_key);
Damien Miller95def091999-11-25 00:26:21 +1100857 error("Add correct host key in %.100s to get rid of this message.",
Ben Lindstrom4dccfa52000-12-28 16:40:05 +0000858 user_hostfile);
Ben Lindstrom46c16222000-12-22 01:43:59 +0000859 error("Offending key in %s:%d", host_file, host_line);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000860
Damien Miller5428f641999-11-25 11:54:57 +1100861 /*
862 * If strict host key checking is in use, the user will have
863 * to edit the key manually and we can only abort.
864 */
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000865 if (options.strict_host_key_checking) {
866 error("%s host key for %.200s has changed and you have "
867 "requested strict checking.", type, host);
868 goto fail;
869 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000870
Damien Miller5428f641999-11-25 11:54:57 +1100871 /*
872 * If strict host key checking has not been requested, allow
Damien Miller941ac452003-06-04 20:31:53 +1000873 * the connection but without MITM-able authentication or
Damien Miller437edb92006-08-05 09:11:13 +1000874 * forwarding.
Damien Miller5428f641999-11-25 11:54:57 +1100875 */
Damien Miller95def091999-11-25 00:26:21 +1100876 if (options.password_authentication) {
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000877 error("Password authentication is disabled to avoid "
878 "man-in-the-middle attacks.");
Damien Miller95def091999-11-25 00:26:21 +1100879 options.password_authentication = 0;
880 }
Damien Miller941ac452003-06-04 20:31:53 +1000881 if (options.kbd_interactive_authentication) {
882 error("Keyboard-interactive authentication is disabled"
883 " to avoid man-in-the-middle attacks.");
884 options.kbd_interactive_authentication = 0;
885 options.challenge_response_authentication = 0;
886 }
887 if (options.challenge_response_authentication) {
888 error("Challenge/response authentication is disabled"
889 " to avoid man-in-the-middle attacks.");
890 options.challenge_response_authentication = 0;
891 }
Damien Miller95def091999-11-25 00:26:21 +1100892 if (options.forward_agent) {
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000893 error("Agent forwarding is disabled to avoid "
894 "man-in-the-middle attacks.");
Damien Miller95def091999-11-25 00:26:21 +1100895 options.forward_agent = 0;
896 }
Ben Lindstromc72745a2000-12-02 19:03:54 +0000897 if (options.forward_x11) {
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000898 error("X11 forwarding is disabled to avoid "
899 "man-in-the-middle attacks.");
Ben Lindstromc72745a2000-12-02 19:03:54 +0000900 options.forward_x11 = 0;
901 }
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000902 if (options.num_local_forwards > 0 ||
903 options.num_remote_forwards > 0) {
904 error("Port forwarding is disabled to avoid "
905 "man-in-the-middle attacks.");
906 options.num_local_forwards =
Damien Miller9f0f5c62001-12-21 14:45:46 +1100907 options.num_remote_forwards = 0;
Ben Lindstromc72745a2000-12-02 19:03:54 +0000908 }
Damien Miller437edb92006-08-05 09:11:13 +1000909 if (options.tun_open != SSH_TUNMODE_NO) {
910 error("Tunnel forwarding is disabled to avoid "
911 "man-in-the-middle attacks.");
912 options.tun_open = SSH_TUNMODE_NO;
913 }
Damien Miller5428f641999-11-25 11:54:57 +1100914 /*
915 * XXX Should permit the user to change to use the new id.
916 * This could be done by converting the host key to an
917 * identifying sentence, tell that the host identifies itself
918 * by that sentence, and ask the user if he/she whishes to
919 * accept the authentication.
920 */
Damien Miller95def091999-11-25 00:26:21 +1100921 break;
Ben Lindstrom3ed66402002-08-01 01:21:56 +0000922 case HOST_FOUND:
923 fatal("internal error");
924 break;
Damien Miller95def091999-11-25 00:26:21 +1100925 }
Ben Lindstromc72745a2000-12-02 19:03:54 +0000926
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000927 if (options.check_host_ip && host_status != HOST_CHANGED &&
928 ip_status == HOST_CHANGED) {
Damien Miller49d795c2002-01-22 23:34:12 +1100929 snprintf(msg, sizeof(msg),
930 "Warning: the %s host key for '%.200s' "
931 "differs from the key for the IP address '%.128s'"
932 "\nOffending key for IP in %s:%d",
933 type, host, ip, ip_file, ip_line);
934 if (host_status == HOST_OK) {
935 len = strlen(msg);
936 snprintf(msg + len, sizeof(msg) - len,
937 "\nMatching host key in %s:%d",
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000938 host_file, host_line);
Damien Miller49d795c2002-01-22 23:34:12 +1100939 }
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000940 if (options.strict_host_key_checking == 1) {
Damien Millerab2db412003-06-02 19:09:13 +1000941 logit("%s", msg);
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000942 error("Exiting, you have requested strict checking.");
943 goto fail;
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000944 } else if (options.strict_host_key_checking == 2) {
Damien Miller49d795c2002-01-22 23:34:12 +1100945 strlcat(msg, "\nAre you sure you want "
946 "to continue connecting (yes/no)? ", sizeof(msg));
947 if (!confirm(msg))
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000948 goto fail;
Damien Miller49d795c2002-01-22 23:34:12 +1100949 } else {
Damien Millerab2db412003-06-02 19:09:13 +1000950 logit("%s", msg);
Ben Lindstrom5c1fbab2001-01-03 03:51:15 +0000951 }
952 }
953
Ben Lindstromc72745a2000-12-02 19:03:54 +0000954 xfree(ip);
Darren Tuckerda345532006-07-10 23:04:19 +1000955 xfree(host);
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000956 return 0;
957
958fail:
959 xfree(ip);
Darren Tuckerda345532006-07-10 23:04:19 +1000960 xfree(host);
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000961 return -1;
962}
963
Damien Miller37876e92003-05-15 10:19:46 +1000964/* returns 0 if key verifies or -1 if key does NOT verify */
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000965int
966verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
967{
968 struct stat st;
Damien Miller150b5572003-11-17 21:19:29 +1100969 int flags = 0;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000970
Damien Miller150b5572003-11-17 21:19:29 +1100971 if (options.verify_host_key_dns &&
972 verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
973
974 if (flags & DNS_VERIFY_FOUND) {
975
976 if (options.verify_host_key_dns == 1 &&
977 flags & DNS_VERIFY_MATCH &&
978 flags & DNS_VERIFY_SECURE)
979 return 0;
980
981 if (flags & DNS_VERIFY_MATCH) {
982 matching_host_key_dns = 1;
983 } else {
984 warn_changed_key(host_key);
985 error("Update the SSHFP RR in DNS with the new "
986 "host key to get rid of this message.");
987 }
Damien Miller37876e92003-05-15 10:19:46 +1000988 }
989 }
Damien Miller37876e92003-05-15 10:19:46 +1000990
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000991 /* return ok if the key can be found in an old keyfile */
992 if (stat(options.system_hostfile2, &st) == 0 ||
993 stat(options.user_hostfile2, &st) == 0) {
Damien Millerda828392006-08-05 11:35:45 +1000994 if (check_host_key(host, hostaddr, options.port, host_key,
995 RDONLY, options.user_hostfile2,
996 options.system_hostfile2) == 0)
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000997 return 0;
998 }
Damien Millerda828392006-08-05 11:35:45 +1000999 return check_host_key(host, hostaddr, options.port, host_key,
1000 RDRW, options.user_hostfile, options.system_hostfile);
Damien Millera34a28b1999-12-14 10:47:15 +11001001}
Damien Miller037a0dc1999-12-07 15:38:31 +11001002
Damien Miller396691a2000-01-20 22:44:08 +11001003/*
1004 * Starts a dialog with the server, and authenticates the current user on the
1005 * server. This does not need any extra privileges. The basic connection
1006 * to the server must already have been established before this is called.
1007 * If login fails, this function prints an error and never returns.
1008 * This function does not require super-user privileges.
1009 */
1010void
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001011ssh_login(Sensitive *sensitive, const char *orighost,
Damien Miller67bd0622007-09-17 12:06:57 +10001012 struct sockaddr *hostaddr, struct passwd *pw, int timeout_ms)
Damien Miller396691a2000-01-20 22:44:08 +11001013{
1014 char *host, *cp;
Damien Millereba71ba2000-04-29 23:57:08 +10001015 char *server_user, *local_user;
1016
Damien Millereba71ba2000-04-29 23:57:08 +10001017 local_user = xstrdup(pw->pw_name);
1018 server_user = options.user ? options.user : local_user;
Damien Miller396691a2000-01-20 22:44:08 +11001019
1020 /* Convert the user-supplied hostname into all lowercase. */
1021 host = xstrdup(orighost);
1022 for (cp = host; *cp; cp++)
1023 if (isupper(*cp))
Damien Miller1d2b6702006-03-26 14:09:54 +11001024 *cp = (char)tolower(*cp);
Damien Miller396691a2000-01-20 22:44:08 +11001025
1026 /* Exchange protocol version identification strings with the server. */
Damien Miller67bd0622007-09-17 12:06:57 +10001027 ssh_exchange_identification(timeout_ms);
Damien Miller396691a2000-01-20 22:44:08 +11001028
1029 /* Put the connection into non-blocking mode. */
1030 packet_set_nonblocking();
1031
Damien Miller396691a2000-01-20 22:44:08 +11001032 /* key exchange */
Damien Miller396691a2000-01-20 22:44:08 +11001033 /* authenticate user */
Damien Miller1383bd82000-04-06 12:32:37 +10001034 if (compat20) {
1035 ssh_kex2(host, hostaddr);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001036 ssh_userauth2(local_user, server_user, host, sensitive);
Damien Miller1383bd82000-04-06 12:32:37 +10001037 } else {
Damien Miller1383bd82000-04-06 12:32:37 +10001038 ssh_kex(host, hostaddr);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001039 ssh_userauth1(local_user, server_user, host, sensitive);
Damien Miller1383bd82000-04-06 12:32:37 +10001040 }
Damien Miller40b59852006-06-13 13:00:25 +10001041 xfree(local_user);
Damien Miller396691a2000-01-20 22:44:08 +11001042}
Damien Miller79438cc2001-02-16 12:34:57 +11001043
1044void
1045ssh_put_password(char *password)
1046{
1047 int size;
1048 char *padded;
1049
Ben Lindstromd20d0f32001-03-10 17:22:20 +00001050 if (datafellows & SSH_BUG_PASSWORDPAD) {
Ben Lindstrom664408d2001-06-09 01:42:01 +00001051 packet_put_cstring(password);
Ben Lindstromd20d0f32001-03-10 17:22:20 +00001052 return;
1053 }
Damien Miller79438cc2001-02-16 12:34:57 +11001054 size = roundup(strlen(password) + 1, 32);
Damien Miller07d86be2006-03-26 14:19:21 +11001055 padded = xcalloc(1, size);
Damien Miller79438cc2001-02-16 12:34:57 +11001056 strlcpy(padded, password, size);
1057 packet_put_string(padded, size);
1058 memset(padded, 0, size);
1059 xfree(padded);
1060}
Ben Lindstrom3ed66402002-08-01 01:21:56 +00001061
1062static int
1063show_key_from_file(const char *file, const char *host, int keytype)
1064{
1065 Key *found;
1066 char *fp;
1067 int line, ret;
1068
1069 found = key_new(keytype);
1070 if ((ret = lookup_key_in_hostfile_by_type(file, host,
1071 keytype, found, &line))) {
1072 fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
Damien Miller996acd22003-04-09 20:59:48 +10001073 logit("WARNING: %s key found for host %s\n"
Ben Lindstrom4b99be82002-08-01 01:26:29 +00001074 "in %s:%d\n"
Ben Lindstrom3ed66402002-08-01 01:21:56 +00001075 "%s key fingerprint %s.",
1076 key_type(found), host, file, line,
1077 key_type(found), fp);
1078 xfree(fp);
1079 }
1080 key_free(found);
1081 return (ret);
1082}
1083
1084/* print all known host keys for a given host, but skip keys of given type */
1085static int
1086show_other_keys(const char *host, Key *key)
1087{
1088 int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1};
1089 int i, found = 0;
1090
1091 for (i = 0; type[i] != -1; i++) {
1092 if (type[i] == key->type)
1093 continue;
1094 if (type[i] != KEY_RSA1 &&
1095 show_key_from_file(options.user_hostfile2, host, type[i])) {
1096 found = 1;
1097 continue;
1098 }
1099 if (type[i] != KEY_RSA1 &&
1100 show_key_from_file(options.system_hostfile2, host, type[i])) {
1101 found = 1;
1102 continue;
1103 }
1104 if (show_key_from_file(options.user_hostfile, host, type[i])) {
1105 found = 1;
1106 continue;
1107 }
1108 if (show_key_from_file(options.system_hostfile, host, type[i])) {
1109 found = 1;
1110 continue;
1111 }
1112 debug2("no key of type %d for host %s", type[i], host);
1113 }
1114 return (found);
1115}
Damien Miller5a388972003-11-17 21:10:47 +11001116
1117static void
1118warn_changed_key(Key *host_key)
1119{
1120 char *fp;
Damien Miller8f746ec2003-11-17 21:11:15 +11001121 const char *type = key_type(host_key);
Damien Miller5a388972003-11-17 21:10:47 +11001122
1123 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
1124
1125 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1126 error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
1127 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1128 error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
1129 error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
1130 error("It is also possible that the %s host key has just been changed.", type);
1131 error("The fingerprint for the %s key sent by the remote host is\n%s.",
1132 type, fp);
1133 error("Please contact your system administrator.");
1134
1135 xfree(fp);
Damien Miller5a388972003-11-17 21:10:47 +11001136}
Damien Millerd27b9472005-12-13 19:29:02 +11001137
1138/*
1139 * Execute a local command
1140 */
1141int
1142ssh_local_cmd(const char *args)
1143{
1144 char *shell;
1145 pid_t pid;
1146 int status;
1147
1148 if (!options.permit_local_command ||
1149 args == NULL || !*args)
1150 return (1);
1151
1152 if ((shell = getenv("SHELL")) == NULL)
1153 shell = _PATH_BSHELL;
1154
1155 pid = fork();
1156 if (pid == 0) {
1157 debug3("Executing %s -c \"%s\"", shell, args);
1158 execl(shell, shell, "-c", args, (char *)NULL);
1159 error("Couldn't execute %s -c \"%s\": %s",
1160 shell, args, strerror(errno));
1161 _exit(1);
1162 } else if (pid == -1)
1163 fatal("fork failed: %.100s", strerror(errno));
1164 while (waitpid(pid, &status, 0) == -1)
1165 if (errno != EINTR)
1166 fatal("Couldn't wait for child: %s", strerror(errno));
1167
1168 if (!WIFEXITED(status))
1169 return (1);
1170
1171 return (WEXITSTATUS(status));
1172}