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8efc0c15 | 1 | /* |
5260325f | 2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
4 | * All rights reserved | |
5260325f | 5 | * Code to connect to a remote host, and to perform the client side of the |
6 | * login (authentication) dialog. | |
bcbf86ec | 7 | * |
8 | * As far as I am concerned, the code I have written for this software | |
9 | * can be used freely for any purpose. Any derived versions of this | |
10 | * software must be clearly marked as such, and if the derived work is | |
11 | * incompatible with the protocol description in the RFC file, it must be | |
12 | * called by a name other than "ssh" or "Secure Shell". | |
5260325f | 13 | */ |
8efc0c15 | 14 | |
15 | #include "includes.h" | |
aa2eae64 | 16 | RCSID("$OpenBSD: sshconnect.c,v 1.174 2006/02/10 01:44:27 stevesk Exp $"); |
17 | ||
18 | #include <sys/types.h> | |
19 | #include <sys/wait.h> | |
a75f5360 | 20 | |
21 | #include <paths.h> | |
8efc0c15 | 22 | |
42f11eb2 | 23 | #include "ssh.h" |
8efc0c15 | 24 | #include "xmalloc.h" |
25 | #include "rsa.h" | |
8ce64345 | 26 | #include "buffer.h" |
8efc0c15 | 27 | #include "packet.h" |
8efc0c15 | 28 | #include "uidswap.h" |
29 | #include "compat.h" | |
4fe2af09 | 30 | #include "key.h" |
a306f2dd | 31 | #include "sshconnect.h" |
4fe2af09 | 32 | #include "hostfile.h" |
42f11eb2 | 33 | #include "log.h" |
34 | #include "readconf.h" | |
35 | #include "atomicio.h" | |
36 | #include "misc.h" | |
21289cd0 | 37 | #include "dns.h" |
21289cd0 | 38 | |
a306f2dd | 39 | char *client_version_string = NULL; |
40 | char *server_version_string = NULL; | |
8ce64345 | 41 | |
ed82a2a9 | 42 | static int matching_host_key_dns = 0; |
1432b5c4 | 43 | |
3fb156df | 44 | /* import */ |
57112b5a | 45 | extern Options options; |
48e671d5 | 46 | extern char *__progname; |
3fb156df | 47 | extern uid_t original_real_uid; |
48 | extern uid_t original_effective_uid; | |
6939bbd4 | 49 | extern pid_t proxy_command_pid; |
57112b5a | 50 | |
a704dd54 | 51 | #ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */ |
52 | #define INET6_ADDRSTRLEN 46 | |
53 | #endif | |
54 | ||
8a48a7ef | 55 | static int show_other_keys(const char *, Key *); |
1a1bc5d5 | 56 | static void warn_changed_key(Key *); |
8a48a7ef | 57 | |
5260325f | 58 | /* |
59 | * Connect to the given ssh server using a proxy command. | |
60 | */ | |
396c147e | 61 | static int |
3fb156df | 62 | ssh_proxy_connect(const char *host, u_short port, const char *proxy_command) |
8efc0c15 | 63 | { |
a980cbd7 | 64 | char *command_string, *tmp; |
5260325f | 65 | int pin[2], pout[2]; |
9da5c3c9 | 66 | pid_t pid; |
48e671d5 | 67 | char strport[NI_MAXSERV]; |
a980cbd7 | 68 | size_t len; |
5260325f | 69 | |
70 | /* Convert the port number into a string. */ | |
48e671d5 | 71 | snprintf(strport, sizeof strport, "%hu", port); |
5260325f | 72 | |
6939bbd4 | 73 | /* |
74 | * Build the final command string in the buffer by making the | |
75 | * appropriate substitutions to the given proxy command. | |
76 | * | |
aff51935 | 77 | * Use "exec" to avoid "sh -c" processes on some platforms |
6939bbd4 | 78 | * (e.g. Solaris) |
79 | */ | |
a980cbd7 | 80 | len = strlen(proxy_command) + 6; |
81 | tmp = xmalloc(len); | |
82 | strlcpy(tmp, "exec ", len); | |
83 | strlcat(tmp, proxy_command, len); | |
84 | command_string = percent_expand(tmp, "h", host, | |
85 | "p", strport, (char *)NULL); | |
86 | xfree(tmp); | |
5260325f | 87 | |
88 | /* Create pipes for communicating with the proxy. */ | |
89 | if (pipe(pin) < 0 || pipe(pout) < 0) | |
90 | fatal("Could not create pipes to communicate with the proxy: %.100s", | |
184eed6a | 91 | strerror(errno)); |
5260325f | 92 | |
93 | debug("Executing proxy command: %.500s", command_string); | |
94 | ||
95 | /* Fork and execute the proxy command. */ | |
96 | if ((pid = fork()) == 0) { | |
97 | char *argv[10]; | |
98 | ||
99 | /* Child. Permanently give up superuser privileges. */ | |
3fb156df | 100 | seteuid(original_real_uid); |
101 | setuid(original_real_uid); | |
5260325f | 102 | |
103 | /* Redirect stdin and stdout. */ | |
104 | close(pin[1]); | |
105 | if (pin[0] != 0) { | |
106 | if (dup2(pin[0], 0) < 0) | |
107 | perror("dup2 stdin"); | |
108 | close(pin[0]); | |
109 | } | |
110 | close(pout[0]); | |
111 | if (dup2(pout[1], 1) < 0) | |
112 | perror("dup2 stdout"); | |
113 | /* Cannot be 1 because pin allocated two descriptors. */ | |
114 | close(pout[1]); | |
115 | ||
116 | /* Stderr is left as it is so that error messages get | |
117 | printed on the user's terminal. */ | |
30228d7c | 118 | argv[0] = _PATH_BSHELL; |
5260325f | 119 | argv[1] = "-c"; |
120 | argv[2] = command_string; | |
121 | argv[3] = NULL; | |
122 | ||
123 | /* Execute the proxy command. Note that we gave up any | |
124 | extra privileges above. */ | |
328654d8 | 125 | execv(argv[0], argv); |
126 | perror(argv[0]); | |
5260325f | 127 | exit(1); |
8efc0c15 | 128 | } |
5260325f | 129 | /* Parent. */ |
130 | if (pid < 0) | |
131 | fatal("fork failed: %.100s", strerror(errno)); | |
6939bbd4 | 132 | else |
133 | proxy_command_pid = pid; /* save pid to clean up later */ | |
5260325f | 134 | |
135 | /* Close child side of the descriptors. */ | |
136 | close(pin[0]); | |
137 | close(pout[1]); | |
138 | ||
139 | /* Free the command name. */ | |
a980cbd7 | 140 | xfree(command_string); |
5260325f | 141 | |
142 | /* Set the connection file descriptors. */ | |
143 | packet_set_connection(pout[0], pin[1]); | |
8efc0c15 | 144 | |
ce773142 | 145 | /* Indicate OK return */ |
146 | return 0; | |
5260325f | 147 | } |
8efc0c15 | 148 | |
5260325f | 149 | /* |
150 | * Creates a (possibly privileged) socket for use as the ssh connection. | |
151 | */ | |
396c147e | 152 | static int |
3e131a6d | 153 | ssh_create_socket(int privileged, struct addrinfo *ai) |
8efc0c15 | 154 | { |
3435f5a6 | 155 | int sock, gaierr; |
156 | struct addrinfo hints, *res; | |
5260325f | 157 | |
aa3378df | 158 | /* |
159 | * If we are running as root and want to connect to a privileged | |
160 | * port, bind our own socket to a privileged port. | |
161 | */ | |
5260325f | 162 | if (privileged) { |
163 | int p = IPPORT_RESERVED - 1; | |
3fb156df | 164 | PRIV_START; |
3e131a6d | 165 | sock = rresvport_af(&p, ai->ai_family); |
3fb156df | 166 | PRIV_END; |
5260325f | 167 | if (sock < 0) |
3e131a6d | 168 | error("rresvport: af=%d %.100s", ai->ai_family, |
169 | strerror(errno)); | |
c8d54615 | 170 | else |
171 | debug("Allocated local port %d.", p); | |
3435f5a6 | 172 | return sock; |
173 | } | |
3e131a6d | 174 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
3435f5a6 | 175 | if (sock < 0) |
176 | error("socket: %.100s", strerror(errno)); | |
3435f5a6 | 177 | |
178 | /* Bind the socket to an alternative local IP address */ | |
179 | if (options.bind_address == NULL) | |
180 | return sock; | |
181 | ||
182 | memset(&hints, 0, sizeof(hints)); | |
3e131a6d | 183 | hints.ai_family = ai->ai_family; |
184 | hints.ai_socktype = ai->ai_socktype; | |
185 | hints.ai_protocol = ai->ai_protocol; | |
3435f5a6 | 186 | hints.ai_flags = AI_PASSIVE; |
187 | gaierr = getaddrinfo(options.bind_address, "0", &hints, &res); | |
188 | if (gaierr) { | |
189 | error("getaddrinfo: %s: %s", options.bind_address, | |
190 | gai_strerror(gaierr)); | |
191 | close(sock); | |
192 | return -1; | |
193 | } | |
194 | if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) { | |
195 | error("bind: %s: %s", options.bind_address, strerror(errno)); | |
196 | close(sock); | |
197 | freeaddrinfo(res); | |
198 | return -1; | |
5260325f | 199 | } |
3435f5a6 | 200 | freeaddrinfo(res); |
5260325f | 201 | return sock; |
8efc0c15 | 202 | } |
203 | ||
09ab3296 | 204 | static int |
205 | timeout_connect(int sockfd, const struct sockaddr *serv_addr, | |
206 | socklen_t addrlen, int timeout) | |
207 | { | |
208 | fd_set *fdset; | |
209 | struct timeval tv; | |
210 | socklen_t optlen; | |
da54f5be | 211 | int fdsetsz, optval, rc, result = -1; |
09ab3296 | 212 | |
213 | if (timeout <= 0) | |
214 | return (connect(sockfd, serv_addr, addrlen)); | |
215 | ||
2daf1db1 | 216 | set_nonblock(sockfd); |
09ab3296 | 217 | rc = connect(sockfd, serv_addr, addrlen); |
2daf1db1 | 218 | if (rc == 0) { |
219 | unset_nonblock(sockfd); | |
09ab3296 | 220 | return (0); |
2daf1db1 | 221 | } |
09ab3296 | 222 | if (errno != EINPROGRESS) |
223 | return (-1); | |
224 | ||
225 | fdsetsz = howmany(sockfd + 1, NFDBITS) * sizeof(fd_mask); | |
226 | fdset = (fd_set *)xmalloc(fdsetsz); | |
227 | ||
7caca6d4 | 228 | memset(fdset, 0, fdsetsz); |
09ab3296 | 229 | FD_SET(sockfd, fdset); |
230 | tv.tv_sec = timeout; | |
231 | tv.tv_usec = 0; | |
232 | ||
f8cc7664 | 233 | for (;;) { |
09ab3296 | 234 | rc = select(sockfd + 1, NULL, fdset, NULL, &tv); |
235 | if (rc != -1 || errno != EINTR) | |
236 | break; | |
237 | } | |
238 | ||
f8cc7664 | 239 | switch (rc) { |
09ab3296 | 240 | case 0: |
241 | /* Timed out */ | |
242 | errno = ETIMEDOUT; | |
da54f5be | 243 | break; |
09ab3296 | 244 | case -1: |
245 | /* Select error */ | |
aff51935 | 246 | debug("select: %s", strerror(errno)); |
da54f5be | 247 | break; |
09ab3296 | 248 | case 1: |
249 | /* Completed or failed */ | |
250 | optval = 0; | |
251 | optlen = sizeof(optval); | |
aff51935 | 252 | if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, |
ce26c02a | 253 | &optlen) == -1) { |
aff51935 | 254 | debug("getsockopt: %s", strerror(errno)); |
da54f5be | 255 | break; |
ce26c02a | 256 | } |
09ab3296 | 257 | if (optval != 0) { |
258 | errno = optval; | |
da54f5be | 259 | break; |
09ab3296 | 260 | } |
da54f5be | 261 | result = 0; |
2daf1db1 | 262 | unset_nonblock(sockfd); |
09ab3296 | 263 | break; |
264 | default: | |
265 | /* Should not occur */ | |
266 | fatal("Bogus return (%d) from select()", rc); | |
267 | } | |
268 | ||
da54f5be | 269 | xfree(fdset); |
270 | return (result); | |
09ab3296 | 271 | } |
272 | ||
5260325f | 273 | /* |
48e671d5 | 274 | * Opens a TCP/IP connection to the remote server on the given host. |
275 | * The address of the remote host will be returned in hostaddr. | |
3fb156df | 276 | * If port is 0, the default port will be used. If needpriv is true, |
5260325f | 277 | * a privileged port will be allocated to make the connection. |
3fb156df | 278 | * This requires super-user privileges if needpriv is true. |
5260325f | 279 | * Connection_attempts specifies the maximum number of tries (one per |
280 | * second). If proxy_command is non-NULL, it specifies the command (with %h | |
281 | * and %p substituted for host and port, respectively) to use to contact | |
282 | * the daemon. | |
283 | */ | |
284 | int | |
48e671d5 | 285 | ssh_connect(const char *host, struct sockaddr_storage * hostaddr, |
dab89049 | 286 | u_short port, int family, int connection_attempts, |
3fb156df | 287 | int needpriv, const char *proxy_command) |
8efc0c15 | 288 | { |
b5c334cc | 289 | int gaierr; |
290 | int on = 1; | |
48e671d5 | 291 | int sock = -1, attempt; |
48e671d5 | 292 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
b5c334cc | 293 | struct addrinfo hints, *ai, *aitop; |
5260325f | 294 | |
a77673cc | 295 | debug2("ssh_connect: needpriv %d", needpriv); |
5260325f | 296 | |
5260325f | 297 | /* If a proxy command is given, connect using it. */ |
298 | if (proxy_command != NULL) | |
3fb156df | 299 | return ssh_proxy_connect(host, port, proxy_command); |
5260325f | 300 | |
301 | /* No proxy command. */ | |
302 | ||
48e671d5 | 303 | memset(&hints, 0, sizeof(hints)); |
dab89049 | 304 | hints.ai_family = family; |
48e671d5 | 305 | hints.ai_socktype = SOCK_STREAM; |
d6133f43 | 306 | snprintf(strport, sizeof strport, "%u", port); |
48e671d5 | 307 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) |
308 | fatal("%s: %.100s: %s", __progname, host, | |
309 | gai_strerror(gaierr)); | |
5260325f | 310 | |
95f1eccc | 311 | /* |
312 | * Try to connect several times. On some machines, the first time | |
313 | * will sometimes fail. In general socket code appears to behave | |
314 | * quite magically on many machines. | |
ce773142 | 315 | */ |
316 | for (attempt = 0; ;) { | |
5260325f | 317 | if (attempt > 0) |
318 | debug("Trying again..."); | |
319 | ||
48e671d5 | 320 | /* Loop through addresses for this host, and try each one in |
6ae2364d | 321 | sequence until the connection succeeds. */ |
48e671d5 | 322 | for (ai = aitop; ai; ai = ai->ai_next) { |
323 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
324 | continue; | |
325 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, | |
326 | ntop, sizeof(ntop), strport, sizeof(strport), | |
327 | NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
328 | error("ssh_connect: getnameinfo failed"); | |
329 | continue; | |
330 | } | |
331 | debug("Connecting to %.200s [%.100s] port %s.", | |
332 | host, ntop, strport); | |
333 | ||
334 | /* Create a socket for connecting. */ | |
3e131a6d | 335 | sock = ssh_create_socket(needpriv, ai); |
48e671d5 | 336 | if (sock < 0) |
ce773142 | 337 | /* Any error is already output */ |
48e671d5 | 338 | continue; |
339 | ||
09ab3296 | 340 | if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen, |
341 | options.connection_timeout) >= 0) { | |
48e671d5 | 342 | /* Successful connection. */ |
cd332296 | 343 | memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen); |
5260325f | 344 | break; |
48e671d5 | 345 | } else { |
c750d869 | 346 | debug("connect to address %s port %s: %s", |
347 | ntop, strport, strerror(errno)); | |
aa3378df | 348 | /* |
349 | * Close the failed socket; there appear to | |
350 | * be some problems when reusing a socket for | |
351 | * which connect() has already returned an | |
352 | * error. | |
353 | */ | |
5260325f | 354 | close(sock); |
355 | } | |
8efc0c15 | 356 | } |
48e671d5 | 357 | if (ai) |
358 | break; /* Successful connection. */ | |
8efc0c15 | 359 | |
ce773142 | 360 | attempt++; |
361 | if (attempt >= connection_attempts) | |
362 | break; | |
5260325f | 363 | /* Sleep a moment before retrying. */ |
364 | sleep(1); | |
365 | } | |
48e671d5 | 366 | |
367 | freeaddrinfo(aitop); | |
368 | ||
5260325f | 369 | /* Return failure if we didn't get a successful connection. */ |
9bd68577 | 370 | if (attempt >= connection_attempts) { |
cf039bd1 | 371 | error("ssh: connect to host %s port %s: %s", |
9bd68577 | 372 | host, strport, strerror(errno)); |
cf039bd1 | 373 | return (-1); |
9bd68577 | 374 | } |
8efc0c15 | 375 | |
5260325f | 376 | debug("Connection established."); |
8efc0c15 | 377 | |
fd573618 | 378 | /* Set SO_KEEPALIVE if requested. */ |
379 | if (options.tcp_keep_alive && | |
b5c334cc | 380 | setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, |
381 | sizeof(on)) < 0) | |
382 | error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); | |
8efc0c15 | 383 | |
5260325f | 384 | /* Set the connection. */ |
385 | packet_set_connection(sock, sock); | |
8efc0c15 | 386 | |
ce773142 | 387 | return 0; |
8efc0c15 | 388 | } |
389 | ||
5260325f | 390 | /* |
391 | * Waits for the server identification string, and sends our own | |
392 | * identification string. | |
393 | */ | |
396c147e | 394 | static void |
5ca51e19 | 395 | ssh_exchange_identification(void) |
8efc0c15 | 396 | { |
5260325f | 397 | char buf[256], remote_version[256]; /* must be same size! */ |
2ceb8101 | 398 | int remote_major, remote_minor, mismatch; |
5260325f | 399 | int connection_in = packet_get_connection_in(); |
400 | int connection_out = packet_get_connection_out(); | |
2b87da3b | 401 | int minor1 = PROTOCOL_MINOR_1; |
2ceb8101 | 402 | u_int i; |
5260325f | 403 | |
05624c18 | 404 | /* Read other side's version identification. */ |
38c295d6 | 405 | for (;;) { |
406 | for (i = 0; i < sizeof(buf) - 1; i++) { | |
05624c18 | 407 | size_t len = atomicio(read, connection_in, &buf[i], 1); |
408 | ||
56964485 | 409 | if (len != 1 && errno == EPIPE) |
38c295d6 | 410 | fatal("ssh_exchange_identification: Connection closed by remote host"); |
05624c18 | 411 | else if (len != 1) |
412 | fatal("ssh_exchange_identification: read: %.100s", strerror(errno)); | |
38c295d6 | 413 | if (buf[i] == '\r') { |
414 | buf[i] = '\n'; | |
415 | buf[i + 1] = 0; | |
416 | continue; /**XXX wait for \n */ | |
417 | } | |
418 | if (buf[i] == '\n') { | |
419 | buf[i + 1] = 0; | |
420 | break; | |
421 | } | |
5260325f | 422 | } |
38c295d6 | 423 | buf[sizeof(buf) - 1] = 0; |
424 | if (strncmp(buf, "SSH-", 4) == 0) | |
5260325f | 425 | break; |
38c295d6 | 426 | debug("ssh_exchange_identification: %s", buf); |
8efc0c15 | 427 | } |
8ce64345 | 428 | server_version_string = xstrdup(buf); |
5260325f | 429 | |
aa3378df | 430 | /* |
431 | * Check that the versions match. In future this might accept | |
432 | * several versions and set appropriate flags to handle them. | |
433 | */ | |
8ce64345 | 434 | if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n", |
435 | &remote_major, &remote_minor, remote_version) != 3) | |
5260325f | 436 | fatal("Bad remote protocol version identification: '%.100s'", buf); |
437 | debug("Remote protocol version %d.%d, remote software version %.100s", | |
184eed6a | 438 | remote_major, remote_minor, remote_version); |
5260325f | 439 | |
8ce64345 | 440 | compat_datafellows(remote_version); |
a8be9f80 | 441 | mismatch = 0; |
442 | ||
6aacefa7 | 443 | switch (remote_major) { |
a8be9f80 | 444 | case 1: |
445 | if (remote_minor == 99 && | |
446 | (options.protocol & SSH_PROTO_2) && | |
447 | !(options.protocol & SSH_PROTO_1_PREFERRED)) { | |
448 | enable_compat20(); | |
449 | break; | |
5260325f | 450 | } |
a8be9f80 | 451 | if (!(options.protocol & SSH_PROTO_1)) { |
452 | mismatch = 1; | |
453 | break; | |
454 | } | |
455 | if (remote_minor < 3) { | |
456 | fatal("Remote machine has too old SSH software version."); | |
fa08c86b | 457 | } else if (remote_minor == 3 || remote_minor == 4) { |
a8be9f80 | 458 | /* We speak 1.3, too. */ |
459 | enable_compat13(); | |
fa08c86b | 460 | minor1 = 3; |
a8be9f80 | 461 | if (options.forward_agent) { |
bbe88b6d | 462 | logit("Agent forwarding disabled for protocol 1.3"); |
a8be9f80 | 463 | options.forward_agent = 0; |
464 | } | |
465 | } | |
466 | break; | |
467 | case 2: | |
468 | if (options.protocol & SSH_PROTO_2) { | |
469 | enable_compat20(); | |
470 | break; | |
471 | } | |
472 | /* FALLTHROUGH */ | |
6ae2364d | 473 | default: |
a8be9f80 | 474 | mismatch = 1; |
475 | break; | |
8efc0c15 | 476 | } |
a8be9f80 | 477 | if (mismatch) |
5260325f | 478 | fatal("Protocol major versions differ: %d vs. %d", |
a8be9f80 | 479 | (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, |
480 | remote_major); | |
5260325f | 481 | /* Send our own protocol version identification. */ |
482 | snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n", | |
a8be9f80 | 483 | compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, |
fa08c86b | 484 | compat20 ? PROTOCOL_MINOR_2 : minor1, |
8ce64345 | 485 | SSH_VERSION); |
dc54438a | 486 | if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf)) |
5260325f | 487 | fatal("write: %.100s", strerror(errno)); |
8ce64345 | 488 | client_version_string = xstrdup(buf); |
489 | chop(client_version_string); | |
490 | chop(server_version_string); | |
491 | debug("Local version string %.100s", client_version_string); | |
8efc0c15 | 492 | } |
493 | ||
f21032a6 | 494 | /* defaults to 'no' */ |
396c147e | 495 | static int |
a2c92c4a | 496 | confirm(const char *prompt) |
8efc0c15 | 497 | { |
616a6b93 | 498 | const char *msg, *again = "Please type 'yes' or 'no': "; |
499 | char *p; | |
500 | int ret = -1; | |
5260325f | 501 | |
f21032a6 | 502 | if (options.batch_mode) |
503 | return 0; | |
616a6b93 | 504 | for (msg = prompt;;msg = again) { |
505 | p = read_passphrase(msg, RP_ECHO); | |
506 | if (p == NULL || | |
507 | (p[0] == '\0') || (p[0] == '\n') || | |
508 | strncasecmp(p, "no", 2) == 0) | |
509 | ret = 0; | |
f11fe301 | 510 | if (p && strncasecmp(p, "yes", 3) == 0) |
616a6b93 | 511 | ret = 1; |
512 | if (p) | |
513 | xfree(p); | |
514 | if (ret != -1) | |
515 | return ret; | |
8efc0c15 | 516 | } |
8efc0c15 | 517 | } |
518 | ||
5260325f | 519 | /* |
f49bc4f7 | 520 | * check whether the supplied host key is valid, return -1 if the key |
521 | * is not valid. the user_hostfile will not be updated if 'readonly' is true. | |
5260325f | 522 | */ |
396c147e | 523 | static int |
a306f2dd | 524 | check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key, |
f49bc4f7 | 525 | int readonly, const char *user_hostfile, const char *system_hostfile) |
8efc0c15 | 526 | { |
4fe2af09 | 527 | Key *file_key; |
b6c7b7b7 | 528 | const char *type = key_type(host_key); |
95f1eccc | 529 | char *ip = NULL; |
22138a36 | 530 | char hostline[1000], *hostp, *fp; |
5260325f | 531 | HostStatus host_status; |
532 | HostStatus ip_status; | |
e79276c2 | 533 | int r, local = 0, host_ip_differ = 0; |
20af321f | 534 | int salen; |
48e671d5 | 535 | char ntop[NI_MAXHOST]; |
616a6b93 | 536 | char msg[1024]; |
1432b5c4 | 537 | int len, host_line, ip_line; |
1e3b8b07 | 538 | const char *host_file = NULL, *ip_file = NULL; |
48e671d5 | 539 | |
540 | /* | |
541 | * Force accepting of the host key for loopback/localhost. The | |
542 | * problem is that if the home directory is NFS-mounted to multiple | |
543 | * machines, localhost will refer to a different machine in each of | |
544 | * them, and the user will get bogus HOST_CHANGED warnings. This | |
545 | * essentially disables host authentication for localhost; however, | |
546 | * this is probably not a real problem. | |
547 | */ | |
a306f2dd | 548 | /** hostaddr == 0! */ |
48e671d5 | 549 | switch (hostaddr->sa_family) { |
550 | case AF_INET: | |
f49bc4f7 | 551 | local = (ntohl(((struct sockaddr_in *)hostaddr)-> |
4e2e5cfd | 552 | sin_addr.s_addr) >> 24) == IN_LOOPBACKNET; |
20af321f | 553 | salen = sizeof(struct sockaddr_in); |
48e671d5 | 554 | break; |
555 | case AF_INET6: | |
f49bc4f7 | 556 | local = IN6_IS_ADDR_LOOPBACK( |
557 | &(((struct sockaddr_in6 *)hostaddr)->sin6_addr)); | |
20af321f | 558 | salen = sizeof(struct sockaddr_in6); |
48e671d5 | 559 | break; |
560 | default: | |
561 | local = 0; | |
20af321f | 562 | salen = sizeof(struct sockaddr_storage); |
48e671d5 | 563 | break; |
564 | } | |
8bbc048a | 565 | if (options.no_host_authentication_for_localhost == 1 && local && |
566 | options.host_key_alias == NULL) { | |
7c49df64 | 567 | debug("Forcing accepting of host key for " |
568 | "loopback/localhost."); | |
f49bc4f7 | 569 | return 0; |
48e671d5 | 570 | } |
5260325f | 571 | |
57112b5a | 572 | /* |
7c49df64 | 573 | * We don't have the remote ip-address for connections |
574 | * using a proxy command | |
575 | */ | |
576 | if (options.proxy_command == NULL) { | |
577 | if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop), | |
578 | NULL, 0, NI_NUMERICHOST) != 0) | |
579 | fatal("check_host_key: getnameinfo failed"); | |
580 | ip = xstrdup(ntop); | |
581 | } else { | |
582 | ip = xstrdup("<no hostip for proxy command>"); | |
583 | } | |
584 | /* | |
585 | * Turn off check_host_ip if the connection is to localhost, via proxy | |
586 | * command or if we don't have a hostname to compare with | |
57112b5a | 587 | */ |
7c49df64 | 588 | if (options.check_host_ip && |
589 | (local || strcmp(host, ip) == 0 || options.proxy_command != NULL)) | |
57112b5a | 590 | options.check_host_ip = 0; |
591 | ||
8abcdba4 | 592 | /* |
7c49df64 | 593 | * Allow the user to record the key under a different name. This is |
8abcdba4 | 594 | * useful for ssh tunneling over forwarded connections or if you run |
7c49df64 | 595 | * multiple sshd's on different ports on the same machine. |
8abcdba4 | 596 | */ |
597 | if (options.host_key_alias != NULL) { | |
598 | host = options.host_key_alias; | |
599 | debug("using hostkeyalias: %s", host); | |
600 | } | |
601 | ||
95f1eccc | 602 | /* |
603 | * Store the host key from the known host file in here so that we can | |
604 | * compare it with the key for the IP address. | |
605 | */ | |
4fe2af09 | 606 | file_key = key_new(host_key->type); |
5260325f | 607 | |
aa3378df | 608 | /* |
7b9b0103 | 609 | * Check if the host key is present in the user's list of known |
aa3378df | 610 | * hosts or in the systemwide list. |
611 | */ | |
1e3b8b07 | 612 | host_file = user_hostfile; |
f49bc4f7 | 613 | host_status = check_host_in_hostfile(host_file, host, host_key, |
184eed6a | 614 | file_key, &host_line); |
1e3b8b07 | 615 | if (host_status == HOST_NEW) { |
616 | host_file = system_hostfile; | |
f49bc4f7 | 617 | host_status = check_host_in_hostfile(host_file, host, host_key, |
618 | file_key, &host_line); | |
1e3b8b07 | 619 | } |
aa3378df | 620 | /* |
621 | * Also perform check for the ip address, skip the check if we are | |
622 | * localhost or the hostname was an ip address to begin with | |
623 | */ | |
7c49df64 | 624 | if (options.check_host_ip) { |
4fe2af09 | 625 | Key *ip_key = key_new(host_key->type); |
5260325f | 626 | |
1e3b8b07 | 627 | ip_file = user_hostfile; |
f49bc4f7 | 628 | ip_status = check_host_in_hostfile(ip_file, ip, host_key, |
629 | ip_key, &ip_line); | |
1e3b8b07 | 630 | if (ip_status == HOST_NEW) { |
631 | ip_file = system_hostfile; | |
f49bc4f7 | 632 | ip_status = check_host_in_hostfile(ip_file, ip, |
633 | host_key, ip_key, &ip_line); | |
1e3b8b07 | 634 | } |
5260325f | 635 | if (host_status == HOST_CHANGED && |
4fe2af09 | 636 | (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key))) |
5260325f | 637 | host_ip_differ = 1; |
638 | ||
4fe2af09 | 639 | key_free(ip_key); |
5260325f | 640 | } else |
641 | ip_status = host_status; | |
642 | ||
4fe2af09 | 643 | key_free(file_key); |
5260325f | 644 | |
645 | switch (host_status) { | |
646 | case HOST_OK: | |
647 | /* The host is known and the key matches. */ | |
1d1ffb87 | 648 | debug("Host '%.200s' is known and matches the %s host key.", |
649 | host, type); | |
1e3b8b07 | 650 | debug("Found key in %s:%d", host_file, host_line); |
7c49df64 | 651 | if (options.check_host_ip && ip_status == HOST_NEW) { |
f49bc4f7 | 652 | if (readonly) |
bbe88b6d | 653 | logit("%s host key for IP address " |
f49bc4f7 | 654 | "'%.128s' not in list of known hosts.", |
7c49df64 | 655 | type, ip); |
f49bc4f7 | 656 | else if (!add_host_to_hostfile(user_hostfile, ip, |
5c63c2ab | 657 | host_key, options.hash_known_hosts)) |
bbe88b6d | 658 | logit("Failed to add the %s host key for IP " |
f49bc4f7 | 659 | "address '%.128s' to the list of known " |
660 | "hosts (%.30s).", type, ip, user_hostfile); | |
661 | else | |
bbe88b6d | 662 | logit("Warning: Permanently added the %s host " |
f49bc4f7 | 663 | "key for IP address '%.128s' to the list " |
664 | "of known hosts.", type, ip); | |
5260325f | 665 | } |
666 | break; | |
667 | case HOST_NEW: | |
f49bc4f7 | 668 | if (readonly) |
669 | goto fail; | |
5260325f | 670 | /* The host is new. */ |
671 | if (options.strict_host_key_checking == 1) { | |
f49bc4f7 | 672 | /* |
673 | * User has requested strict host key checking. We | |
674 | * will not add the host key automatically. The only | |
675 | * alternative left is to abort. | |
676 | */ | |
677 | error("No %s host key is known for %.200s and you " | |
678 | "have requested strict checking.", type, host); | |
679 | goto fail; | |
5260325f | 680 | } else if (options.strict_host_key_checking == 2) { |
1432b5c4 | 681 | char msg1[1024], msg2[1024]; |
682 | ||
683 | if (show_other_keys(host, host_key)) | |
684 | snprintf(msg1, sizeof(msg1), | |
4e2e5cfd | 685 | "\nbut keys of different type are already" |
686 | " known for this host."); | |
1432b5c4 | 687 | else |
688 | snprintf(msg1, sizeof(msg1), "."); | |
5260325f | 689 | /* The default */ |
22138a36 | 690 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
1432b5c4 | 691 | msg2[0] = '\0'; |
1432b5c4 | 692 | if (options.verify_host_key_dns) { |
0161a13d | 693 | if (matching_host_key_dns) |
1432b5c4 | 694 | snprintf(msg2, sizeof(msg2), |
695 | "Matching host key fingerprint" | |
696 | " found in DNS.\n"); | |
697 | else | |
698 | snprintf(msg2, sizeof(msg2), | |
699 | "No matching host key fingerprint" | |
700 | " found in DNS.\n"); | |
701 | } | |
616a6b93 | 702 | snprintf(msg, sizeof(msg), |
f49bc4f7 | 703 | "The authenticity of host '%.200s (%s)' can't be " |
8a48a7ef | 704 | "established%s\n" |
1432b5c4 | 705 | "%s key fingerprint is %s.\n%s" |
f49bc4f7 | 706 | "Are you sure you want to continue connecting " |
8a48a7ef | 707 | "(yes/no)? ", |
1432b5c4 | 708 | host, ip, msg1, type, fp, msg2); |
22138a36 | 709 | xfree(fp); |
616a6b93 | 710 | if (!confirm(msg)) |
f49bc4f7 | 711 | goto fail; |
5260325f | 712 | } |
f49bc4f7 | 713 | /* |
714 | * If not in strict mode, add the key automatically to the | |
715 | * local known_hosts file. | |
716 | */ | |
e79276c2 | 717 | if (options.check_host_ip && ip_status == HOST_NEW) { |
718 | snprintf(hostline, sizeof(hostline), "%s,%s", | |
719 | host, ip); | |
720 | hostp = hostline; | |
721 | if (options.hash_known_hosts) { | |
722 | /* Add hash of host and IP separately */ | |
723 | r = add_host_to_hostfile(user_hostfile, host, | |
724 | host_key, options.hash_known_hosts) && | |
725 | add_host_to_hostfile(user_hostfile, ip, | |
726 | host_key, options.hash_known_hosts); | |
727 | } else { | |
728 | /* Add unhashed "host,ip" */ | |
729 | r = add_host_to_hostfile(user_hostfile, | |
730 | hostline, host_key, | |
731 | options.hash_known_hosts); | |
732 | } | |
733 | } else { | |
734 | r = add_host_to_hostfile(user_hostfile, host, host_key, | |
735 | options.hash_known_hosts); | |
736 | hostp = host; | |
737 | } | |
738 | ||
739 | if (!r) | |
bbe88b6d | 740 | logit("Failed to add the host to the list of known " |
f49bc4f7 | 741 | "hosts (%.500s).", user_hostfile); |
5260325f | 742 | else |
bbe88b6d | 743 | logit("Warning: Permanently added '%.200s' (%s) to the " |
f49bc4f7 | 744 | "list of known hosts.", hostp, type); |
5260325f | 745 | break; |
746 | case HOST_CHANGED: | |
747 | if (options.check_host_ip && host_ip_differ) { | |
ca75d7de | 748 | char *key_msg; |
5260325f | 749 | if (ip_status == HOST_NEW) |
ca75d7de | 750 | key_msg = "is unknown"; |
5260325f | 751 | else if (ip_status == HOST_OK) |
ca75d7de | 752 | key_msg = "is unchanged"; |
5260325f | 753 | else |
ca75d7de | 754 | key_msg = "has a different value"; |
5260325f | 755 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
756 | error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @"); | |
757 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); | |
1d1ffb87 | 758 | error("The %s host key for %s has changed,", type, host); |
5260325f | 759 | error("and the key for the according IP address %s", ip); |
ca75d7de | 760 | error("%s. This could either mean that", key_msg); |
5260325f | 761 | error("DNS SPOOFING is happening or the IP address for the host"); |
1e3b8b07 | 762 | error("and its host key have changed at the same time."); |
7c49df64 | 763 | if (ip_status != HOST_NEW) |
1e3b8b07 | 764 | error("Offending key for IP in %s:%d", ip_file, ip_line); |
5260325f | 765 | } |
766 | /* The host key has changed. */ | |
1a1bc5d5 | 767 | warn_changed_key(host_key); |
5260325f | 768 | error("Add correct host key in %.100s to get rid of this message.", |
8abcdba4 | 769 | user_hostfile); |
1e3b8b07 | 770 | error("Offending key in %s:%d", host_file, host_line); |
5260325f | 771 | |
aa3378df | 772 | /* |
773 | * If strict host key checking is in use, the user will have | |
774 | * to edit the key manually and we can only abort. | |
775 | */ | |
f49bc4f7 | 776 | if (options.strict_host_key_checking) { |
777 | error("%s host key for %.200s has changed and you have " | |
778 | "requested strict checking.", type, host); | |
779 | goto fail; | |
780 | } | |
5260325f | 781 | |
aa3378df | 782 | /* |
783 | * If strict host key checking has not been requested, allow | |
d453a600 | 784 | * the connection but without MITM-able authentication or |
aa3378df | 785 | * agent forwarding. |
786 | */ | |
5260325f | 787 | if (options.password_authentication) { |
f49bc4f7 | 788 | error("Password authentication is disabled to avoid " |
789 | "man-in-the-middle attacks."); | |
5260325f | 790 | options.password_authentication = 0; |
791 | } | |
d453a600 | 792 | if (options.kbd_interactive_authentication) { |
793 | error("Keyboard-interactive authentication is disabled" | |
794 | " to avoid man-in-the-middle attacks."); | |
795 | options.kbd_interactive_authentication = 0; | |
796 | options.challenge_response_authentication = 0; | |
797 | } | |
798 | if (options.challenge_response_authentication) { | |
799 | error("Challenge/response authentication is disabled" | |
800 | " to avoid man-in-the-middle attacks."); | |
801 | options.challenge_response_authentication = 0; | |
802 | } | |
5260325f | 803 | if (options.forward_agent) { |
f49bc4f7 | 804 | error("Agent forwarding is disabled to avoid " |
805 | "man-in-the-middle attacks."); | |
5260325f | 806 | options.forward_agent = 0; |
807 | } | |
0b6fbf03 | 808 | if (options.forward_x11) { |
f49bc4f7 | 809 | error("X11 forwarding is disabled to avoid " |
810 | "man-in-the-middle attacks."); | |
0b6fbf03 | 811 | options.forward_x11 = 0; |
812 | } | |
f49bc4f7 | 813 | if (options.num_local_forwards > 0 || |
814 | options.num_remote_forwards > 0) { | |
815 | error("Port forwarding is disabled to avoid " | |
816 | "man-in-the-middle attacks."); | |
817 | options.num_local_forwards = | |
184eed6a | 818 | options.num_remote_forwards = 0; |
0b6fbf03 | 819 | } |
aa3378df | 820 | /* |
821 | * XXX Should permit the user to change to use the new id. | |
822 | * This could be done by converting the host key to an | |
823 | * identifying sentence, tell that the host identifies itself | |
824 | * by that sentence, and ask the user if he/she whishes to | |
825 | * accept the authentication. | |
826 | */ | |
5260325f | 827 | break; |
8a48a7ef | 828 | case HOST_FOUND: |
829 | fatal("internal error"); | |
830 | break; | |
5260325f | 831 | } |
0b6fbf03 | 832 | |
7c49df64 | 833 | if (options.check_host_ip && host_status != HOST_CHANGED && |
834 | ip_status == HOST_CHANGED) { | |
616a6b93 | 835 | snprintf(msg, sizeof(msg), |
836 | "Warning: the %s host key for '%.200s' " | |
837 | "differs from the key for the IP address '%.128s'" | |
838 | "\nOffending key for IP in %s:%d", | |
839 | type, host, ip, ip_file, ip_line); | |
840 | if (host_status == HOST_OK) { | |
841 | len = strlen(msg); | |
842 | snprintf(msg + len, sizeof(msg) - len, | |
843 | "\nMatching host key in %s:%d", | |
7203d6bb | 844 | host_file, host_line); |
616a6b93 | 845 | } |
7c49df64 | 846 | if (options.strict_host_key_checking == 1) { |
b0545fe6 | 847 | logit("%s", msg); |
f49bc4f7 | 848 | error("Exiting, you have requested strict checking."); |
849 | goto fail; | |
7c49df64 | 850 | } else if (options.strict_host_key_checking == 2) { |
616a6b93 | 851 | strlcat(msg, "\nAre you sure you want " |
852 | "to continue connecting (yes/no)? ", sizeof(msg)); | |
853 | if (!confirm(msg)) | |
f49bc4f7 | 854 | goto fail; |
616a6b93 | 855 | } else { |
b0545fe6 | 856 | logit("%s", msg); |
7c49df64 | 857 | } |
858 | } | |
859 | ||
0b6fbf03 | 860 | xfree(ip); |
f49bc4f7 | 861 | return 0; |
862 | ||
863 | fail: | |
864 | xfree(ip); | |
865 | return -1; | |
866 | } | |
867 | ||
21289cd0 | 868 | /* returns 0 if key verifies or -1 if key does NOT verify */ |
f49bc4f7 | 869 | int |
870 | verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key) | |
871 | { | |
872 | struct stat st; | |
0161a13d | 873 | int flags = 0; |
f49bc4f7 | 874 | |
0161a13d | 875 | if (options.verify_host_key_dns && |
876 | verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) { | |
877 | ||
878 | if (flags & DNS_VERIFY_FOUND) { | |
879 | ||
880 | if (options.verify_host_key_dns == 1 && | |
881 | flags & DNS_VERIFY_MATCH && | |
882 | flags & DNS_VERIFY_SECURE) | |
883 | return 0; | |
884 | ||
885 | if (flags & DNS_VERIFY_MATCH) { | |
886 | matching_host_key_dns = 1; | |
887 | } else { | |
888 | warn_changed_key(host_key); | |
889 | error("Update the SSHFP RR in DNS with the new " | |
890 | "host key to get rid of this message."); | |
891 | } | |
21289cd0 | 892 | } |
893 | } | |
21289cd0 | 894 | |
f49bc4f7 | 895 | /* return ok if the key can be found in an old keyfile */ |
896 | if (stat(options.system_hostfile2, &st) == 0 || | |
897 | stat(options.user_hostfile2, &st) == 0) { | |
898 | if (check_host_key(host, hostaddr, host_key, /*readonly*/ 1, | |
899 | options.user_hostfile2, options.system_hostfile2) == 0) | |
900 | return 0; | |
901 | } | |
902 | return check_host_key(host, hostaddr, host_key, /*readonly*/ 0, | |
903 | options.user_hostfile, options.system_hostfile); | |
95f1eccc | 904 | } |
905 | ||
8ce64345 | 906 | /* |
a306f2dd | 907 | * Starts a dialog with the server, and authenticates the current user on the |
908 | * server. This does not need any extra privileges. The basic connection | |
909 | * to the server must already have been established before this is called. | |
910 | * If login fails, this function prints an error and never returns. | |
911 | * This function does not require super-user privileges. | |
8ce64345 | 912 | */ |
913 | void | |
39c00dc2 | 914 | ssh_login(Sensitive *sensitive, const char *orighost, |
63bd8c36 | 915 | struct sockaddr *hostaddr, struct passwd *pw) |
8ce64345 | 916 | { |
a306f2dd | 917 | char *host, *cp; |
8ce64345 | 918 | char *server_user, *local_user; |
8ce64345 | 919 | |
8ce64345 | 920 | local_user = xstrdup(pw->pw_name); |
921 | server_user = options.user ? options.user : local_user; | |
922 | ||
7b2ea3a1 | 923 | /* Convert the user-supplied hostname into all lowercase. */ |
924 | host = xstrdup(orighost); | |
925 | for (cp = host; *cp; cp++) | |
926 | if (isupper(*cp)) | |
927 | *cp = tolower(*cp); | |
928 | ||
929 | /* Exchange protocol version identification strings with the server. */ | |
930 | ssh_exchange_identification(); | |
931 | ||
932 | /* Put the connection into non-blocking mode. */ | |
933 | packet_set_nonblocking(); | |
934 | ||
7b2ea3a1 | 935 | /* key exchange */ |
7b2ea3a1 | 936 | /* authenticate user */ |
8ce64345 | 937 | if (compat20) { |
938 | ssh_kex2(host, hostaddr); | |
39c00dc2 | 939 | ssh_userauth2(local_user, server_user, host, sensitive); |
8ce64345 | 940 | } else { |
8ce64345 | 941 | ssh_kex(host, hostaddr); |
39c00dc2 | 942 | ssh_userauth1(local_user, server_user, host, sensitive); |
8ce64345 | 943 | } |
7b2ea3a1 | 944 | } |
0ae4fe1d | 945 | |
946 | void | |
947 | ssh_put_password(char *password) | |
948 | { | |
949 | int size; | |
950 | char *padded; | |
951 | ||
99c415db | 952 | if (datafellows & SSH_BUG_PASSWORDPAD) { |
449c5ba5 | 953 | packet_put_cstring(password); |
99c415db | 954 | return; |
955 | } | |
0ae4fe1d | 956 | size = roundup(strlen(password) + 1, 32); |
957 | padded = xmalloc(size); | |
958 | memset(padded, 0, size); | |
959 | strlcpy(padded, password, size); | |
960 | packet_put_string(padded, size); | |
961 | memset(padded, 0, size); | |
962 | xfree(padded); | |
963 | } | |
8a48a7ef | 964 | |
965 | static int | |
966 | show_key_from_file(const char *file, const char *host, int keytype) | |
967 | { | |
968 | Key *found; | |
969 | char *fp; | |
970 | int line, ret; | |
971 | ||
972 | found = key_new(keytype); | |
973 | if ((ret = lookup_key_in_hostfile_by_type(file, host, | |
974 | keytype, found, &line))) { | |
975 | fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX); | |
bbe88b6d | 976 | logit("WARNING: %s key found for host %s\n" |
567a05bf | 977 | "in %s:%d\n" |
8a48a7ef | 978 | "%s key fingerprint %s.", |
979 | key_type(found), host, file, line, | |
980 | key_type(found), fp); | |
981 | xfree(fp); | |
982 | } | |
983 | key_free(found); | |
984 | return (ret); | |
985 | } | |
986 | ||
987 | /* print all known host keys for a given host, but skip keys of given type */ | |
988 | static int | |
989 | show_other_keys(const char *host, Key *key) | |
990 | { | |
991 | int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1}; | |
992 | int i, found = 0; | |
993 | ||
994 | for (i = 0; type[i] != -1; i++) { | |
995 | if (type[i] == key->type) | |
996 | continue; | |
997 | if (type[i] != KEY_RSA1 && | |
998 | show_key_from_file(options.user_hostfile2, host, type[i])) { | |
999 | found = 1; | |
1000 | continue; | |
1001 | } | |
1002 | if (type[i] != KEY_RSA1 && | |
1003 | show_key_from_file(options.system_hostfile2, host, type[i])) { | |
1004 | found = 1; | |
1005 | continue; | |
1006 | } | |
1007 | if (show_key_from_file(options.user_hostfile, host, type[i])) { | |
1008 | found = 1; | |
1009 | continue; | |
1010 | } | |
1011 | if (show_key_from_file(options.system_hostfile, host, type[i])) { | |
1012 | found = 1; | |
1013 | continue; | |
1014 | } | |
1015 | debug2("no key of type %d for host %s", type[i], host); | |
1016 | } | |
1017 | return (found); | |
1018 | } | |
1a1bc5d5 | 1019 | |
1020 | static void | |
1021 | warn_changed_key(Key *host_key) | |
1022 | { | |
1023 | char *fp; | |
f5da7f70 | 1024 | const char *type = key_type(host_key); |
1a1bc5d5 | 1025 | |
1026 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); | |
1027 | ||
1028 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); | |
1029 | error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @"); | |
1030 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); | |
1031 | error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!"); | |
1032 | error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!"); | |
1033 | error("It is also possible that the %s host key has just been changed.", type); | |
1034 | error("The fingerprint for the %s key sent by the remote host is\n%s.", | |
1035 | type, fp); | |
1036 | error("Please contact your system administrator."); | |
1037 | ||
1038 | xfree(fp); | |
1a1bc5d5 | 1039 | } |
d20f3c9e | 1040 | |
1041 | /* | |
1042 | * Execute a local command | |
1043 | */ | |
1044 | int | |
1045 | ssh_local_cmd(const char *args) | |
1046 | { | |
1047 | char *shell; | |
1048 | pid_t pid; | |
1049 | int status; | |
1050 | ||
1051 | if (!options.permit_local_command || | |
1052 | args == NULL || !*args) | |
1053 | return (1); | |
1054 | ||
1055 | if ((shell = getenv("SHELL")) == NULL) | |
1056 | shell = _PATH_BSHELL; | |
1057 | ||
1058 | pid = fork(); | |
1059 | if (pid == 0) { | |
1060 | debug3("Executing %s -c \"%s\"", shell, args); | |
1061 | execl(shell, shell, "-c", args, (char *)NULL); | |
1062 | error("Couldn't execute %s -c \"%s\": %s", | |
1063 | shell, args, strerror(errno)); | |
1064 | _exit(1); | |
1065 | } else if (pid == -1) | |
1066 | fatal("fork failed: %.100s", strerror(errno)); | |
1067 | while (waitpid(pid, &status, 0) == -1) | |
1068 | if (errno != EINTR) | |
1069 | fatal("Couldn't wait for child: %s", strerror(errno)); | |
1070 | ||
1071 | if (!WIFEXITED(status)) | |
1072 | return (1); | |
1073 | ||
1074 | return (WEXITSTATUS(status)); | |
1075 | } |