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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" | |
a980cbd7 | 16 | RCSID("$OpenBSD: sshconnect.c,v 1.164 2005/06/06 11:20:36 djm Exp $"); |
8efc0c15 | 17 | |
8ce64345 | 18 | #include <openssl/bn.h> |
a306f2dd | 19 | |
42f11eb2 | 20 | #include "ssh.h" |
8efc0c15 | 21 | #include "xmalloc.h" |
22 | #include "rsa.h" | |
8ce64345 | 23 | #include "buffer.h" |
8efc0c15 | 24 | #include "packet.h" |
8efc0c15 | 25 | #include "uidswap.h" |
26 | #include "compat.h" | |
4fe2af09 | 27 | #include "key.h" |
a306f2dd | 28 | #include "sshconnect.h" |
4fe2af09 | 29 | #include "hostfile.h" |
42f11eb2 | 30 | #include "log.h" |
31 | #include "readconf.h" | |
32 | #include "atomicio.h" | |
33 | #include "misc.h" | |
8efc0c15 | 34 | |
21289cd0 | 35 | #include "dns.h" |
21289cd0 | 36 | |
a306f2dd | 37 | char *client_version_string = NULL; |
38 | char *server_version_string = NULL; | |
8ce64345 | 39 | |
0161a13d | 40 | int matching_host_key_dns = 0; |
1432b5c4 | 41 | |
3fb156df | 42 | /* import */ |
57112b5a | 43 | extern Options options; |
48e671d5 | 44 | extern char *__progname; |
3fb156df | 45 | extern uid_t original_real_uid; |
46 | extern uid_t original_effective_uid; | |
6939bbd4 | 47 | extern pid_t proxy_command_pid; |
57112b5a | 48 | |
a704dd54 | 49 | #ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */ |
50 | #define INET6_ADDRSTRLEN 46 | |
51 | #endif | |
52 | ||
8a48a7ef | 53 | static int show_other_keys(const char *, Key *); |
1a1bc5d5 | 54 | static void warn_changed_key(Key *); |
8a48a7ef | 55 | |
5260325f | 56 | /* |
57 | * Connect to the given ssh server using a proxy command. | |
58 | */ | |
396c147e | 59 | static int |
3fb156df | 60 | ssh_proxy_connect(const char *host, u_short port, const char *proxy_command) |
8efc0c15 | 61 | { |
a980cbd7 | 62 | char *command_string, *tmp; |
5260325f | 63 | int pin[2], pout[2]; |
9da5c3c9 | 64 | pid_t pid; |
48e671d5 | 65 | char strport[NI_MAXSERV]; |
a980cbd7 | 66 | size_t len; |
5260325f | 67 | |
68 | /* Convert the port number into a string. */ | |
48e671d5 | 69 | snprintf(strport, sizeof strport, "%hu", port); |
5260325f | 70 | |
6939bbd4 | 71 | /* |
72 | * Build the final command string in the buffer by making the | |
73 | * appropriate substitutions to the given proxy command. | |
74 | * | |
aff51935 | 75 | * Use "exec" to avoid "sh -c" processes on some platforms |
6939bbd4 | 76 | * (e.g. Solaris) |
77 | */ | |
a980cbd7 | 78 | len = strlen(proxy_command) + 6; |
79 | tmp = xmalloc(len); | |
80 | strlcpy(tmp, "exec ", len); | |
81 | strlcat(tmp, proxy_command, len); | |
82 | command_string = percent_expand(tmp, "h", host, | |
83 | "p", strport, (char *)NULL); | |
84 | xfree(tmp); | |
5260325f | 85 | |
86 | /* Create pipes for communicating with the proxy. */ | |
87 | if (pipe(pin) < 0 || pipe(pout) < 0) | |
88 | fatal("Could not create pipes to communicate with the proxy: %.100s", | |
184eed6a | 89 | strerror(errno)); |
5260325f | 90 | |
91 | debug("Executing proxy command: %.500s", command_string); | |
92 | ||
93 | /* Fork and execute the proxy command. */ | |
94 | if ((pid = fork()) == 0) { | |
95 | char *argv[10]; | |
96 | ||
97 | /* Child. Permanently give up superuser privileges. */ | |
3fb156df | 98 | seteuid(original_real_uid); |
99 | setuid(original_real_uid); | |
5260325f | 100 | |
101 | /* Redirect stdin and stdout. */ | |
102 | close(pin[1]); | |
103 | if (pin[0] != 0) { | |
104 | if (dup2(pin[0], 0) < 0) | |
105 | perror("dup2 stdin"); | |
106 | close(pin[0]); | |
107 | } | |
108 | close(pout[0]); | |
109 | if (dup2(pout[1], 1) < 0) | |
110 | perror("dup2 stdout"); | |
111 | /* Cannot be 1 because pin allocated two descriptors. */ | |
112 | close(pout[1]); | |
113 | ||
114 | /* Stderr is left as it is so that error messages get | |
115 | printed on the user's terminal. */ | |
30228d7c | 116 | argv[0] = _PATH_BSHELL; |
5260325f | 117 | argv[1] = "-c"; |
118 | argv[2] = command_string; | |
119 | argv[3] = NULL; | |
120 | ||
121 | /* Execute the proxy command. Note that we gave up any | |
122 | extra privileges above. */ | |
328654d8 | 123 | execv(argv[0], argv); |
124 | perror(argv[0]); | |
5260325f | 125 | exit(1); |
8efc0c15 | 126 | } |
5260325f | 127 | /* Parent. */ |
128 | if (pid < 0) | |
129 | fatal("fork failed: %.100s", strerror(errno)); | |
6939bbd4 | 130 | else |
131 | proxy_command_pid = pid; /* save pid to clean up later */ | |
5260325f | 132 | |
133 | /* Close child side of the descriptors. */ | |
134 | close(pin[0]); | |
135 | close(pout[1]); | |
136 | ||
137 | /* Free the command name. */ | |
a980cbd7 | 138 | xfree(command_string); |
5260325f | 139 | |
140 | /* Set the connection file descriptors. */ | |
141 | packet_set_connection(pout[0], pin[1]); | |
8efc0c15 | 142 | |
ce773142 | 143 | /* Indicate OK return */ |
144 | return 0; | |
5260325f | 145 | } |
8efc0c15 | 146 | |
5260325f | 147 | /* |
148 | * Creates a (possibly privileged) socket for use as the ssh connection. | |
149 | */ | |
396c147e | 150 | static int |
3e131a6d | 151 | ssh_create_socket(int privileged, struct addrinfo *ai) |
8efc0c15 | 152 | { |
3435f5a6 | 153 | int sock, gaierr; |
154 | struct addrinfo hints, *res; | |
5260325f | 155 | |
aa3378df | 156 | /* |
157 | * If we are running as root and want to connect to a privileged | |
158 | * port, bind our own socket to a privileged port. | |
159 | */ | |
5260325f | 160 | if (privileged) { |
161 | int p = IPPORT_RESERVED - 1; | |
3fb156df | 162 | PRIV_START; |
3e131a6d | 163 | sock = rresvport_af(&p, ai->ai_family); |
3fb156df | 164 | PRIV_END; |
5260325f | 165 | if (sock < 0) |
3e131a6d | 166 | error("rresvport: af=%d %.100s", ai->ai_family, |
167 | strerror(errno)); | |
c8d54615 | 168 | else |
169 | debug("Allocated local port %d.", p); | |
3435f5a6 | 170 | return sock; |
171 | } | |
3e131a6d | 172 | sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol); |
3435f5a6 | 173 | if (sock < 0) |
174 | error("socket: %.100s", strerror(errno)); | |
3435f5a6 | 175 | |
176 | /* Bind the socket to an alternative local IP address */ | |
177 | if (options.bind_address == NULL) | |
178 | return sock; | |
179 | ||
180 | memset(&hints, 0, sizeof(hints)); | |
3e131a6d | 181 | hints.ai_family = ai->ai_family; |
182 | hints.ai_socktype = ai->ai_socktype; | |
183 | hints.ai_protocol = ai->ai_protocol; | |
3435f5a6 | 184 | hints.ai_flags = AI_PASSIVE; |
185 | gaierr = getaddrinfo(options.bind_address, "0", &hints, &res); | |
186 | if (gaierr) { | |
187 | error("getaddrinfo: %s: %s", options.bind_address, | |
188 | gai_strerror(gaierr)); | |
189 | close(sock); | |
190 | return -1; | |
191 | } | |
192 | if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) { | |
193 | error("bind: %s: %s", options.bind_address, strerror(errno)); | |
194 | close(sock); | |
195 | freeaddrinfo(res); | |
196 | return -1; | |
5260325f | 197 | } |
3435f5a6 | 198 | freeaddrinfo(res); |
5260325f | 199 | return sock; |
8efc0c15 | 200 | } |
201 | ||
09ab3296 | 202 | static int |
203 | timeout_connect(int sockfd, const struct sockaddr *serv_addr, | |
204 | socklen_t addrlen, int timeout) | |
205 | { | |
206 | fd_set *fdset; | |
207 | struct timeval tv; | |
208 | socklen_t optlen; | |
da54f5be | 209 | int fdsetsz, optval, rc, result = -1; |
09ab3296 | 210 | |
211 | if (timeout <= 0) | |
212 | return (connect(sockfd, serv_addr, addrlen)); | |
213 | ||
2daf1db1 | 214 | set_nonblock(sockfd); |
09ab3296 | 215 | rc = connect(sockfd, serv_addr, addrlen); |
2daf1db1 | 216 | if (rc == 0) { |
217 | unset_nonblock(sockfd); | |
09ab3296 | 218 | return (0); |
2daf1db1 | 219 | } |
09ab3296 | 220 | if (errno != EINPROGRESS) |
221 | return (-1); | |
222 | ||
223 | fdsetsz = howmany(sockfd + 1, NFDBITS) * sizeof(fd_mask); | |
224 | fdset = (fd_set *)xmalloc(fdsetsz); | |
225 | ||
7caca6d4 | 226 | memset(fdset, 0, fdsetsz); |
09ab3296 | 227 | FD_SET(sockfd, fdset); |
228 | tv.tv_sec = timeout; | |
229 | tv.tv_usec = 0; | |
230 | ||
f8cc7664 | 231 | for (;;) { |
09ab3296 | 232 | rc = select(sockfd + 1, NULL, fdset, NULL, &tv); |
233 | if (rc != -1 || errno != EINTR) | |
234 | break; | |
235 | } | |
236 | ||
f8cc7664 | 237 | switch (rc) { |
09ab3296 | 238 | case 0: |
239 | /* Timed out */ | |
240 | errno = ETIMEDOUT; | |
da54f5be | 241 | break; |
09ab3296 | 242 | case -1: |
243 | /* Select error */ | |
aff51935 | 244 | debug("select: %s", strerror(errno)); |
da54f5be | 245 | break; |
09ab3296 | 246 | case 1: |
247 | /* Completed or failed */ | |
248 | optval = 0; | |
249 | optlen = sizeof(optval); | |
aff51935 | 250 | if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, |
ce26c02a | 251 | &optlen) == -1) { |
aff51935 | 252 | debug("getsockopt: %s", strerror(errno)); |
da54f5be | 253 | break; |
ce26c02a | 254 | } |
09ab3296 | 255 | if (optval != 0) { |
256 | errno = optval; | |
da54f5be | 257 | break; |
09ab3296 | 258 | } |
da54f5be | 259 | result = 0; |
2daf1db1 | 260 | unset_nonblock(sockfd); |
09ab3296 | 261 | break; |
262 | default: | |
263 | /* Should not occur */ | |
264 | fatal("Bogus return (%d) from select()", rc); | |
265 | } | |
266 | ||
da54f5be | 267 | xfree(fdset); |
268 | return (result); | |
09ab3296 | 269 | } |
270 | ||
5260325f | 271 | /* |
48e671d5 | 272 | * Opens a TCP/IP connection to the remote server on the given host. |
273 | * The address of the remote host will be returned in hostaddr. | |
3fb156df | 274 | * If port is 0, the default port will be used. If needpriv is true, |
5260325f | 275 | * a privileged port will be allocated to make the connection. |
3fb156df | 276 | * This requires super-user privileges if needpriv is true. |
5260325f | 277 | * Connection_attempts specifies the maximum number of tries (one per |
278 | * second). If proxy_command is non-NULL, it specifies the command (with %h | |
279 | * and %p substituted for host and port, respectively) to use to contact | |
280 | * the daemon. | |
281 | */ | |
282 | int | |
48e671d5 | 283 | ssh_connect(const char *host, struct sockaddr_storage * hostaddr, |
dab89049 | 284 | u_short port, int family, int connection_attempts, |
3fb156df | 285 | int needpriv, const char *proxy_command) |
8efc0c15 | 286 | { |
b5c334cc | 287 | int gaierr; |
288 | int on = 1; | |
48e671d5 | 289 | int sock = -1, attempt; |
48e671d5 | 290 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; |
b5c334cc | 291 | struct addrinfo hints, *ai, *aitop; |
b5c334cc | 292 | struct servent *sp; |
5260325f | 293 | |
a77673cc | 294 | debug2("ssh_connect: needpriv %d", needpriv); |
5260325f | 295 | |
296 | /* Get default port if port has not been set. */ | |
297 | if (port == 0) { | |
298 | sp = getservbyname(SSH_SERVICE_NAME, "tcp"); | |
299 | if (sp) | |
300 | port = ntohs(sp->s_port); | |
301 | else | |
302 | port = SSH_DEFAULT_PORT; | |
8efc0c15 | 303 | } |
5260325f | 304 | /* If a proxy command is given, connect using it. */ |
305 | if (proxy_command != NULL) | |
3fb156df | 306 | return ssh_proxy_connect(host, port, proxy_command); |
5260325f | 307 | |
308 | /* No proxy command. */ | |
309 | ||
48e671d5 | 310 | memset(&hints, 0, sizeof(hints)); |
dab89049 | 311 | hints.ai_family = family; |
48e671d5 | 312 | hints.ai_socktype = SOCK_STREAM; |
d6133f43 | 313 | snprintf(strport, sizeof strport, "%u", port); |
48e671d5 | 314 | if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) |
315 | fatal("%s: %.100s: %s", __progname, host, | |
316 | gai_strerror(gaierr)); | |
5260325f | 317 | |
95f1eccc | 318 | /* |
319 | * Try to connect several times. On some machines, the first time | |
320 | * will sometimes fail. In general socket code appears to behave | |
321 | * quite magically on many machines. | |
ce773142 | 322 | */ |
323 | for (attempt = 0; ;) { | |
5260325f | 324 | if (attempt > 0) |
325 | debug("Trying again..."); | |
326 | ||
48e671d5 | 327 | /* Loop through addresses for this host, and try each one in |
6ae2364d | 328 | sequence until the connection succeeds. */ |
48e671d5 | 329 | for (ai = aitop; ai; ai = ai->ai_next) { |
330 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
331 | continue; | |
332 | if (getnameinfo(ai->ai_addr, ai->ai_addrlen, | |
333 | ntop, sizeof(ntop), strport, sizeof(strport), | |
334 | NI_NUMERICHOST|NI_NUMERICSERV) != 0) { | |
335 | error("ssh_connect: getnameinfo failed"); | |
336 | continue; | |
337 | } | |
338 | debug("Connecting to %.200s [%.100s] port %s.", | |
339 | host, ntop, strport); | |
340 | ||
341 | /* Create a socket for connecting. */ | |
3e131a6d | 342 | sock = ssh_create_socket(needpriv, ai); |
48e671d5 | 343 | if (sock < 0) |
ce773142 | 344 | /* Any error is already output */ |
48e671d5 | 345 | continue; |
346 | ||
09ab3296 | 347 | if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen, |
348 | options.connection_timeout) >= 0) { | |
48e671d5 | 349 | /* Successful connection. */ |
cd332296 | 350 | memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen); |
5260325f | 351 | break; |
48e671d5 | 352 | } else { |
c750d869 | 353 | debug("connect to address %s port %s: %s", |
354 | ntop, strport, strerror(errno)); | |
aa3378df | 355 | /* |
356 | * Close the failed socket; there appear to | |
357 | * be some problems when reusing a socket for | |
358 | * which connect() has already returned an | |
359 | * error. | |
360 | */ | |
5260325f | 361 | close(sock); |
362 | } | |
8efc0c15 | 363 | } |
48e671d5 | 364 | if (ai) |
365 | break; /* Successful connection. */ | |
8efc0c15 | 366 | |
ce773142 | 367 | attempt++; |
368 | if (attempt >= connection_attempts) | |
369 | break; | |
5260325f | 370 | /* Sleep a moment before retrying. */ |
371 | sleep(1); | |
372 | } | |
48e671d5 | 373 | |
374 | freeaddrinfo(aitop); | |
375 | ||
5260325f | 376 | /* Return failure if we didn't get a successful connection. */ |
9bd68577 | 377 | if (attempt >= connection_attempts) { |
cf039bd1 | 378 | error("ssh: connect to host %s port %s: %s", |
9bd68577 | 379 | host, strport, strerror(errno)); |
cf039bd1 | 380 | return (-1); |
9bd68577 | 381 | } |
8efc0c15 | 382 | |
5260325f | 383 | debug("Connection established."); |
8efc0c15 | 384 | |
fd573618 | 385 | /* Set SO_KEEPALIVE if requested. */ |
386 | if (options.tcp_keep_alive && | |
b5c334cc | 387 | setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on, |
388 | sizeof(on)) < 0) | |
389 | error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); | |
8efc0c15 | 390 | |
5260325f | 391 | /* Set the connection. */ |
392 | packet_set_connection(sock, sock); | |
8efc0c15 | 393 | |
ce773142 | 394 | return 0; |
8efc0c15 | 395 | } |
396 | ||
5260325f | 397 | /* |
398 | * Waits for the server identification string, and sends our own | |
399 | * identification string. | |
400 | */ | |
396c147e | 401 | static void |
5ca51e19 | 402 | ssh_exchange_identification(void) |
8efc0c15 | 403 | { |
5260325f | 404 | char buf[256], remote_version[256]; /* must be same size! */ |
a8be9f80 | 405 | int remote_major, remote_minor, i, mismatch; |
5260325f | 406 | int connection_in = packet_get_connection_in(); |
407 | int connection_out = packet_get_connection_out(); | |
2b87da3b | 408 | int minor1 = PROTOCOL_MINOR_1; |
5260325f | 409 | |
05624c18 | 410 | /* Read other side's version identification. */ |
38c295d6 | 411 | for (;;) { |
412 | for (i = 0; i < sizeof(buf) - 1; i++) { | |
05624c18 | 413 | size_t len = atomicio(read, connection_in, &buf[i], 1); |
414 | ||
415 | if (len != 1 && errno == EPIPE) | |
38c295d6 | 416 | fatal("ssh_exchange_identification: Connection closed by remote host"); |
05624c18 | 417 | else if (len != 1) |
418 | fatal("ssh_exchange_identification: read: %.100s", strerror(errno)); | |
38c295d6 | 419 | if (buf[i] == '\r') { |
420 | buf[i] = '\n'; | |
421 | buf[i + 1] = 0; | |
422 | continue; /**XXX wait for \n */ | |
423 | } | |
424 | if (buf[i] == '\n') { | |
425 | buf[i + 1] = 0; | |
426 | break; | |
427 | } | |
5260325f | 428 | } |
38c295d6 | 429 | buf[sizeof(buf) - 1] = 0; |
430 | if (strncmp(buf, "SSH-", 4) == 0) | |
5260325f | 431 | break; |
38c295d6 | 432 | debug("ssh_exchange_identification: %s", buf); |
8efc0c15 | 433 | } |
8ce64345 | 434 | server_version_string = xstrdup(buf); |
5260325f | 435 | |
aa3378df | 436 | /* |
437 | * Check that the versions match. In future this might accept | |
438 | * several versions and set appropriate flags to handle them. | |
439 | */ | |
8ce64345 | 440 | if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n", |
441 | &remote_major, &remote_minor, remote_version) != 3) | |
5260325f | 442 | fatal("Bad remote protocol version identification: '%.100s'", buf); |
443 | debug("Remote protocol version %d.%d, remote software version %.100s", | |
184eed6a | 444 | remote_major, remote_minor, remote_version); |
5260325f | 445 | |
8ce64345 | 446 | compat_datafellows(remote_version); |
a8be9f80 | 447 | mismatch = 0; |
448 | ||
6aacefa7 | 449 | switch (remote_major) { |
a8be9f80 | 450 | case 1: |
451 | if (remote_minor == 99 && | |
452 | (options.protocol & SSH_PROTO_2) && | |
453 | !(options.protocol & SSH_PROTO_1_PREFERRED)) { | |
454 | enable_compat20(); | |
455 | break; | |
5260325f | 456 | } |
a8be9f80 | 457 | if (!(options.protocol & SSH_PROTO_1)) { |
458 | mismatch = 1; | |
459 | break; | |
460 | } | |
461 | if (remote_minor < 3) { | |
462 | fatal("Remote machine has too old SSH software version."); | |
fa08c86b | 463 | } else if (remote_minor == 3 || remote_minor == 4) { |
a8be9f80 | 464 | /* We speak 1.3, too. */ |
465 | enable_compat13(); | |
fa08c86b | 466 | minor1 = 3; |
a8be9f80 | 467 | if (options.forward_agent) { |
bbe88b6d | 468 | logit("Agent forwarding disabled for protocol 1.3"); |
a8be9f80 | 469 | options.forward_agent = 0; |
470 | } | |
471 | } | |
472 | break; | |
473 | case 2: | |
474 | if (options.protocol & SSH_PROTO_2) { | |
475 | enable_compat20(); | |
476 | break; | |
477 | } | |
478 | /* FALLTHROUGH */ | |
6ae2364d | 479 | default: |
a8be9f80 | 480 | mismatch = 1; |
481 | break; | |
8efc0c15 | 482 | } |
a8be9f80 | 483 | if (mismatch) |
5260325f | 484 | fatal("Protocol major versions differ: %d vs. %d", |
a8be9f80 | 485 | (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, |
486 | remote_major); | |
5260325f | 487 | /* Send our own protocol version identification. */ |
488 | snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n", | |
a8be9f80 | 489 | compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1, |
fa08c86b | 490 | compat20 ? PROTOCOL_MINOR_2 : minor1, |
8ce64345 | 491 | SSH_VERSION); |
dc54438a | 492 | if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf)) |
5260325f | 493 | fatal("write: %.100s", strerror(errno)); |
8ce64345 | 494 | client_version_string = xstrdup(buf); |
495 | chop(client_version_string); | |
496 | chop(server_version_string); | |
497 | debug("Local version string %.100s", client_version_string); | |
8efc0c15 | 498 | } |
499 | ||
f21032a6 | 500 | /* defaults to 'no' */ |
396c147e | 501 | static int |
a2c92c4a | 502 | confirm(const char *prompt) |
8efc0c15 | 503 | { |
616a6b93 | 504 | const char *msg, *again = "Please type 'yes' or 'no': "; |
505 | char *p; | |
506 | int ret = -1; | |
5260325f | 507 | |
f21032a6 | 508 | if (options.batch_mode) |
509 | return 0; | |
616a6b93 | 510 | for (msg = prompt;;msg = again) { |
511 | p = read_passphrase(msg, RP_ECHO); | |
512 | if (p == NULL || | |
513 | (p[0] == '\0') || (p[0] == '\n') || | |
514 | strncasecmp(p, "no", 2) == 0) | |
515 | ret = 0; | |
f11fe301 | 516 | if (p && strncasecmp(p, "yes", 3) == 0) |
616a6b93 | 517 | ret = 1; |
518 | if (p) | |
519 | xfree(p); | |
520 | if (ret != -1) | |
521 | return ret; | |
8efc0c15 | 522 | } |
8efc0c15 | 523 | } |
524 | ||
5260325f | 525 | /* |
f49bc4f7 | 526 | * check whether the supplied host key is valid, return -1 if the key |
527 | * is not valid. the user_hostfile will not be updated if 'readonly' is true. | |
5260325f | 528 | */ |
396c147e | 529 | static int |
a306f2dd | 530 | check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key, |
f49bc4f7 | 531 | int readonly, const char *user_hostfile, const char *system_hostfile) |
8efc0c15 | 532 | { |
4fe2af09 | 533 | Key *file_key; |
b6c7b7b7 | 534 | const char *type = key_type(host_key); |
95f1eccc | 535 | char *ip = NULL; |
22138a36 | 536 | char hostline[1000], *hostp, *fp; |
5260325f | 537 | HostStatus host_status; |
538 | HostStatus ip_status; | |
e79276c2 | 539 | int r, local = 0, host_ip_differ = 0; |
20af321f | 540 | int salen; |
48e671d5 | 541 | char ntop[NI_MAXHOST]; |
616a6b93 | 542 | char msg[1024]; |
1432b5c4 | 543 | int len, host_line, ip_line; |
1e3b8b07 | 544 | const char *host_file = NULL, *ip_file = NULL; |
48e671d5 | 545 | |
546 | /* | |
547 | * Force accepting of the host key for loopback/localhost. The | |
548 | * problem is that if the home directory is NFS-mounted to multiple | |
549 | * machines, localhost will refer to a different machine in each of | |
550 | * them, and the user will get bogus HOST_CHANGED warnings. This | |
551 | * essentially disables host authentication for localhost; however, | |
552 | * this is probably not a real problem. | |
553 | */ | |
a306f2dd | 554 | /** hostaddr == 0! */ |
48e671d5 | 555 | switch (hostaddr->sa_family) { |
556 | case AF_INET: | |
f49bc4f7 | 557 | local = (ntohl(((struct sockaddr_in *)hostaddr)-> |
20a11d35 | 558 | sin_addr.s_addr) >> 24) == IN_LOOPBACKNET; |
20af321f | 559 | salen = sizeof(struct sockaddr_in); |
48e671d5 | 560 | break; |
561 | case AF_INET6: | |
f49bc4f7 | 562 | local = IN6_IS_ADDR_LOOPBACK( |
563 | &(((struct sockaddr_in6 *)hostaddr)->sin6_addr)); | |
20af321f | 564 | salen = sizeof(struct sockaddr_in6); |
48e671d5 | 565 | break; |
566 | default: | |
567 | local = 0; | |
20af321f | 568 | salen = sizeof(struct sockaddr_storage); |
48e671d5 | 569 | break; |
570 | } | |
8bbc048a | 571 | if (options.no_host_authentication_for_localhost == 1 && local && |
572 | options.host_key_alias == NULL) { | |
7c49df64 | 573 | debug("Forcing accepting of host key for " |
574 | "loopback/localhost."); | |
f49bc4f7 | 575 | return 0; |
48e671d5 | 576 | } |
5260325f | 577 | |
57112b5a | 578 | /* |
7c49df64 | 579 | * We don't have the remote ip-address for connections |
580 | * using a proxy command | |
581 | */ | |
582 | if (options.proxy_command == NULL) { | |
583 | if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop), | |
584 | NULL, 0, NI_NUMERICHOST) != 0) | |
585 | fatal("check_host_key: getnameinfo failed"); | |
586 | ip = xstrdup(ntop); | |
587 | } else { | |
588 | ip = xstrdup("<no hostip for proxy command>"); | |
589 | } | |
590 | /* | |
591 | * Turn off check_host_ip if the connection is to localhost, via proxy | |
592 | * command or if we don't have a hostname to compare with | |
57112b5a | 593 | */ |
7c49df64 | 594 | if (options.check_host_ip && |
595 | (local || strcmp(host, ip) == 0 || options.proxy_command != NULL)) | |
57112b5a | 596 | options.check_host_ip = 0; |
597 | ||
8abcdba4 | 598 | /* |
7c49df64 | 599 | * Allow the user to record the key under a different name. This is |
8abcdba4 | 600 | * useful for ssh tunneling over forwarded connections or if you run |
7c49df64 | 601 | * multiple sshd's on different ports on the same machine. |
8abcdba4 | 602 | */ |
603 | if (options.host_key_alias != NULL) { | |
604 | host = options.host_key_alias; | |
605 | debug("using hostkeyalias: %s", host); | |
606 | } | |
607 | ||
95f1eccc | 608 | /* |
609 | * Store the host key from the known host file in here so that we can | |
610 | * compare it with the key for the IP address. | |
611 | */ | |
4fe2af09 | 612 | file_key = key_new(host_key->type); |
5260325f | 613 | |
aa3378df | 614 | /* |
615 | * Check if the host key is present in the user\'s list of known | |
616 | * hosts or in the systemwide list. | |
617 | */ | |
1e3b8b07 | 618 | host_file = user_hostfile; |
f49bc4f7 | 619 | host_status = check_host_in_hostfile(host_file, host, host_key, |
184eed6a | 620 | file_key, &host_line); |
1e3b8b07 | 621 | if (host_status == HOST_NEW) { |
622 | host_file = system_hostfile; | |
f49bc4f7 | 623 | host_status = check_host_in_hostfile(host_file, host, host_key, |
624 | file_key, &host_line); | |
1e3b8b07 | 625 | } |
aa3378df | 626 | /* |
627 | * Also perform check for the ip address, skip the check if we are | |
628 | * localhost or the hostname was an ip address to begin with | |
629 | */ | |
7c49df64 | 630 | if (options.check_host_ip) { |
4fe2af09 | 631 | Key *ip_key = key_new(host_key->type); |
5260325f | 632 | |
1e3b8b07 | 633 | ip_file = user_hostfile; |
f49bc4f7 | 634 | ip_status = check_host_in_hostfile(ip_file, ip, host_key, |
635 | ip_key, &ip_line); | |
1e3b8b07 | 636 | if (ip_status == HOST_NEW) { |
637 | ip_file = system_hostfile; | |
f49bc4f7 | 638 | ip_status = check_host_in_hostfile(ip_file, ip, |
639 | host_key, ip_key, &ip_line); | |
1e3b8b07 | 640 | } |
5260325f | 641 | if (host_status == HOST_CHANGED && |
4fe2af09 | 642 | (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key))) |
5260325f | 643 | host_ip_differ = 1; |
644 | ||
4fe2af09 | 645 | key_free(ip_key); |
5260325f | 646 | } else |
647 | ip_status = host_status; | |
648 | ||
4fe2af09 | 649 | key_free(file_key); |
5260325f | 650 | |
651 | switch (host_status) { | |
652 | case HOST_OK: | |
653 | /* The host is known and the key matches. */ | |
1d1ffb87 | 654 | debug("Host '%.200s' is known and matches the %s host key.", |
655 | host, type); | |
1e3b8b07 | 656 | debug("Found key in %s:%d", host_file, host_line); |
7c49df64 | 657 | if (options.check_host_ip && ip_status == HOST_NEW) { |
f49bc4f7 | 658 | if (readonly) |
bbe88b6d | 659 | logit("%s host key for IP address " |
f49bc4f7 | 660 | "'%.128s' not in list of known hosts.", |
7c49df64 | 661 | type, ip); |
f49bc4f7 | 662 | else if (!add_host_to_hostfile(user_hostfile, ip, |
5c63c2ab | 663 | host_key, options.hash_known_hosts)) |
bbe88b6d | 664 | logit("Failed to add the %s host key for IP " |
f49bc4f7 | 665 | "address '%.128s' to the list of known " |
666 | "hosts (%.30s).", type, ip, user_hostfile); | |
667 | else | |
bbe88b6d | 668 | logit("Warning: Permanently added the %s host " |
f49bc4f7 | 669 | "key for IP address '%.128s' to the list " |
670 | "of known hosts.", type, ip); | |
5260325f | 671 | } |
672 | break; | |
673 | case HOST_NEW: | |
f49bc4f7 | 674 | if (readonly) |
675 | goto fail; | |
5260325f | 676 | /* The host is new. */ |
677 | if (options.strict_host_key_checking == 1) { | |
f49bc4f7 | 678 | /* |
679 | * User has requested strict host key checking. We | |
680 | * will not add the host key automatically. The only | |
681 | * alternative left is to abort. | |
682 | */ | |
683 | error("No %s host key is known for %.200s and you " | |
684 | "have requested strict checking.", type, host); | |
685 | goto fail; | |
5260325f | 686 | } else if (options.strict_host_key_checking == 2) { |
1432b5c4 | 687 | char msg1[1024], msg2[1024]; |
688 | ||
689 | if (show_other_keys(host, host_key)) | |
690 | snprintf(msg1, sizeof(msg1), | |
691 | "\nbut keys of different type are already" | |
692 | " known for this host."); | |
693 | else | |
694 | snprintf(msg1, sizeof(msg1), "."); | |
5260325f | 695 | /* The default */ |
22138a36 | 696 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); |
1432b5c4 | 697 | msg2[0] = '\0'; |
1432b5c4 | 698 | if (options.verify_host_key_dns) { |
0161a13d | 699 | if (matching_host_key_dns) |
1432b5c4 | 700 | snprintf(msg2, sizeof(msg2), |
701 | "Matching host key fingerprint" | |
702 | " found in DNS.\n"); | |
703 | else | |
704 | snprintf(msg2, sizeof(msg2), | |
705 | "No matching host key fingerprint" | |
706 | " found in DNS.\n"); | |
707 | } | |
616a6b93 | 708 | snprintf(msg, sizeof(msg), |
f49bc4f7 | 709 | "The authenticity of host '%.200s (%s)' can't be " |
8a48a7ef | 710 | "established%s\n" |
1432b5c4 | 711 | "%s key fingerprint is %s.\n%s" |
f49bc4f7 | 712 | "Are you sure you want to continue connecting " |
8a48a7ef | 713 | "(yes/no)? ", |
1432b5c4 | 714 | host, ip, msg1, type, fp, msg2); |
22138a36 | 715 | xfree(fp); |
616a6b93 | 716 | if (!confirm(msg)) |
f49bc4f7 | 717 | goto fail; |
5260325f | 718 | } |
f49bc4f7 | 719 | /* |
720 | * If not in strict mode, add the key automatically to the | |
721 | * local known_hosts file. | |
722 | */ | |
e79276c2 | 723 | if (options.check_host_ip && ip_status == HOST_NEW) { |
724 | snprintf(hostline, sizeof(hostline), "%s,%s", | |
725 | host, ip); | |
726 | hostp = hostline; | |
727 | if (options.hash_known_hosts) { | |
728 | /* Add hash of host and IP separately */ | |
729 | r = add_host_to_hostfile(user_hostfile, host, | |
730 | host_key, options.hash_known_hosts) && | |
731 | add_host_to_hostfile(user_hostfile, ip, | |
732 | host_key, options.hash_known_hosts); | |
733 | } else { | |
734 | /* Add unhashed "host,ip" */ | |
735 | r = add_host_to_hostfile(user_hostfile, | |
736 | hostline, host_key, | |
737 | options.hash_known_hosts); | |
738 | } | |
739 | } else { | |
740 | r = add_host_to_hostfile(user_hostfile, host, host_key, | |
741 | options.hash_known_hosts); | |
742 | hostp = host; | |
743 | } | |
744 | ||
745 | if (!r) | |
bbe88b6d | 746 | logit("Failed to add the host to the list of known " |
f49bc4f7 | 747 | "hosts (%.500s).", user_hostfile); |
5260325f | 748 | else |
bbe88b6d | 749 | logit("Warning: Permanently added '%.200s' (%s) to the " |
f49bc4f7 | 750 | "list of known hosts.", hostp, type); |
5260325f | 751 | break; |
752 | case HOST_CHANGED: | |
753 | if (options.check_host_ip && host_ip_differ) { | |
ca75d7de | 754 | char *key_msg; |
5260325f | 755 | if (ip_status == HOST_NEW) |
ca75d7de | 756 | key_msg = "is unknown"; |
5260325f | 757 | else if (ip_status == HOST_OK) |
ca75d7de | 758 | key_msg = "is unchanged"; |
5260325f | 759 | else |
ca75d7de | 760 | key_msg = "has a different value"; |
5260325f | 761 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); |
762 | error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @"); | |
763 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); | |
1d1ffb87 | 764 | error("The %s host key for %s has changed,", type, host); |
5260325f | 765 | error("and the key for the according IP address %s", ip); |
ca75d7de | 766 | error("%s. This could either mean that", key_msg); |
5260325f | 767 | error("DNS SPOOFING is happening or the IP address for the host"); |
1e3b8b07 | 768 | error("and its host key have changed at the same time."); |
7c49df64 | 769 | if (ip_status != HOST_NEW) |
1e3b8b07 | 770 | error("Offending key for IP in %s:%d", ip_file, ip_line); |
5260325f | 771 | } |
772 | /* The host key has changed. */ | |
1a1bc5d5 | 773 | warn_changed_key(host_key); |
5260325f | 774 | error("Add correct host key in %.100s to get rid of this message.", |
8abcdba4 | 775 | user_hostfile); |
1e3b8b07 | 776 | error("Offending key in %s:%d", host_file, host_line); |
5260325f | 777 | |
aa3378df | 778 | /* |
779 | * If strict host key checking is in use, the user will have | |
780 | * to edit the key manually and we can only abort. | |
781 | */ | |
f49bc4f7 | 782 | if (options.strict_host_key_checking) { |
783 | error("%s host key for %.200s has changed and you have " | |
784 | "requested strict checking.", type, host); | |
785 | goto fail; | |
786 | } | |
5260325f | 787 | |
aa3378df | 788 | /* |
789 | * If strict host key checking has not been requested, allow | |
d453a600 | 790 | * the connection but without MITM-able authentication or |
aa3378df | 791 | * agent forwarding. |
792 | */ | |
5260325f | 793 | if (options.password_authentication) { |
f49bc4f7 | 794 | error("Password authentication is disabled to avoid " |
795 | "man-in-the-middle attacks."); | |
5260325f | 796 | options.password_authentication = 0; |
797 | } | |
d453a600 | 798 | if (options.kbd_interactive_authentication) { |
799 | error("Keyboard-interactive authentication is disabled" | |
800 | " to avoid man-in-the-middle attacks."); | |
801 | options.kbd_interactive_authentication = 0; | |
802 | options.challenge_response_authentication = 0; | |
803 | } | |
804 | if (options.challenge_response_authentication) { | |
805 | error("Challenge/response authentication is disabled" | |
806 | " to avoid man-in-the-middle attacks."); | |
807 | options.challenge_response_authentication = 0; | |
808 | } | |
5260325f | 809 | if (options.forward_agent) { |
f49bc4f7 | 810 | error("Agent forwarding is disabled to avoid " |
811 | "man-in-the-middle attacks."); | |
5260325f | 812 | options.forward_agent = 0; |
813 | } | |
0b6fbf03 | 814 | if (options.forward_x11) { |
f49bc4f7 | 815 | error("X11 forwarding is disabled to avoid " |
816 | "man-in-the-middle attacks."); | |
0b6fbf03 | 817 | options.forward_x11 = 0; |
818 | } | |
f49bc4f7 | 819 | if (options.num_local_forwards > 0 || |
820 | options.num_remote_forwards > 0) { | |
821 | error("Port forwarding is disabled to avoid " | |
822 | "man-in-the-middle attacks."); | |
823 | options.num_local_forwards = | |
184eed6a | 824 | options.num_remote_forwards = 0; |
0b6fbf03 | 825 | } |
aa3378df | 826 | /* |
827 | * XXX Should permit the user to change to use the new id. | |
828 | * This could be done by converting the host key to an | |
829 | * identifying sentence, tell that the host identifies itself | |
830 | * by that sentence, and ask the user if he/she whishes to | |
831 | * accept the authentication. | |
832 | */ | |
5260325f | 833 | break; |
8a48a7ef | 834 | case HOST_FOUND: |
835 | fatal("internal error"); | |
836 | break; | |
5260325f | 837 | } |
0b6fbf03 | 838 | |
7c49df64 | 839 | if (options.check_host_ip && host_status != HOST_CHANGED && |
840 | ip_status == HOST_CHANGED) { | |
616a6b93 | 841 | snprintf(msg, sizeof(msg), |
842 | "Warning: the %s host key for '%.200s' " | |
843 | "differs from the key for the IP address '%.128s'" | |
844 | "\nOffending key for IP in %s:%d", | |
845 | type, host, ip, ip_file, ip_line); | |
846 | if (host_status == HOST_OK) { | |
847 | len = strlen(msg); | |
848 | snprintf(msg + len, sizeof(msg) - len, | |
849 | "\nMatching host key in %s:%d", | |
7203d6bb | 850 | host_file, host_line); |
616a6b93 | 851 | } |
7c49df64 | 852 | if (options.strict_host_key_checking == 1) { |
b0545fe6 | 853 | logit("%s", msg); |
f49bc4f7 | 854 | error("Exiting, you have requested strict checking."); |
855 | goto fail; | |
7c49df64 | 856 | } else if (options.strict_host_key_checking == 2) { |
616a6b93 | 857 | strlcat(msg, "\nAre you sure you want " |
858 | "to continue connecting (yes/no)? ", sizeof(msg)); | |
859 | if (!confirm(msg)) | |
f49bc4f7 | 860 | goto fail; |
616a6b93 | 861 | } else { |
b0545fe6 | 862 | logit("%s", msg); |
7c49df64 | 863 | } |
864 | } | |
865 | ||
0b6fbf03 | 866 | xfree(ip); |
f49bc4f7 | 867 | return 0; |
868 | ||
869 | fail: | |
870 | xfree(ip); | |
871 | return -1; | |
872 | } | |
873 | ||
21289cd0 | 874 | /* returns 0 if key verifies or -1 if key does NOT verify */ |
f49bc4f7 | 875 | int |
876 | verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key) | |
877 | { | |
878 | struct stat st; | |
0161a13d | 879 | int flags = 0; |
f49bc4f7 | 880 | |
0161a13d | 881 | if (options.verify_host_key_dns && |
882 | verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) { | |
883 | ||
884 | if (flags & DNS_VERIFY_FOUND) { | |
885 | ||
886 | if (options.verify_host_key_dns == 1 && | |
887 | flags & DNS_VERIFY_MATCH && | |
888 | flags & DNS_VERIFY_SECURE) | |
889 | return 0; | |
890 | ||
891 | if (flags & DNS_VERIFY_MATCH) { | |
892 | matching_host_key_dns = 1; | |
893 | } else { | |
894 | warn_changed_key(host_key); | |
895 | error("Update the SSHFP RR in DNS with the new " | |
896 | "host key to get rid of this message."); | |
897 | } | |
21289cd0 | 898 | } |
899 | } | |
21289cd0 | 900 | |
f49bc4f7 | 901 | /* return ok if the key can be found in an old keyfile */ |
902 | if (stat(options.system_hostfile2, &st) == 0 || | |
903 | stat(options.user_hostfile2, &st) == 0) { | |
904 | if (check_host_key(host, hostaddr, host_key, /*readonly*/ 1, | |
905 | options.user_hostfile2, options.system_hostfile2) == 0) | |
906 | return 0; | |
907 | } | |
908 | return check_host_key(host, hostaddr, host_key, /*readonly*/ 0, | |
909 | options.user_hostfile, options.system_hostfile); | |
95f1eccc | 910 | } |
911 | ||
8ce64345 | 912 | /* |
a306f2dd | 913 | * Starts a dialog with the server, and authenticates the current user on the |
914 | * server. This does not need any extra privileges. The basic connection | |
915 | * to the server must already have been established before this is called. | |
916 | * If login fails, this function prints an error and never returns. | |
917 | * This function does not require super-user privileges. | |
8ce64345 | 918 | */ |
919 | void | |
39c00dc2 | 920 | ssh_login(Sensitive *sensitive, const char *orighost, |
63bd8c36 | 921 | struct sockaddr *hostaddr, struct passwd *pw) |
8ce64345 | 922 | { |
a306f2dd | 923 | char *host, *cp; |
8ce64345 | 924 | char *server_user, *local_user; |
8ce64345 | 925 | |
8ce64345 | 926 | local_user = xstrdup(pw->pw_name); |
927 | server_user = options.user ? options.user : local_user; | |
928 | ||
7b2ea3a1 | 929 | /* Convert the user-supplied hostname into all lowercase. */ |
930 | host = xstrdup(orighost); | |
931 | for (cp = host; *cp; cp++) | |
932 | if (isupper(*cp)) | |
933 | *cp = tolower(*cp); | |
934 | ||
935 | /* Exchange protocol version identification strings with the server. */ | |
936 | ssh_exchange_identification(); | |
937 | ||
938 | /* Put the connection into non-blocking mode. */ | |
939 | packet_set_nonblocking(); | |
940 | ||
7b2ea3a1 | 941 | /* key exchange */ |
7b2ea3a1 | 942 | /* authenticate user */ |
8ce64345 | 943 | if (compat20) { |
944 | ssh_kex2(host, hostaddr); | |
39c00dc2 | 945 | ssh_userauth2(local_user, server_user, host, sensitive); |
8ce64345 | 946 | } else { |
8ce64345 | 947 | ssh_kex(host, hostaddr); |
39c00dc2 | 948 | ssh_userauth1(local_user, server_user, host, sensitive); |
8ce64345 | 949 | } |
7b2ea3a1 | 950 | } |
0ae4fe1d | 951 | |
952 | void | |
953 | ssh_put_password(char *password) | |
954 | { | |
955 | int size; | |
956 | char *padded; | |
957 | ||
99c415db | 958 | if (datafellows & SSH_BUG_PASSWORDPAD) { |
449c5ba5 | 959 | packet_put_cstring(password); |
99c415db | 960 | return; |
961 | } | |
0ae4fe1d | 962 | size = roundup(strlen(password) + 1, 32); |
963 | padded = xmalloc(size); | |
964 | memset(padded, 0, size); | |
965 | strlcpy(padded, password, size); | |
966 | packet_put_string(padded, size); | |
967 | memset(padded, 0, size); | |
968 | xfree(padded); | |
969 | } | |
8a48a7ef | 970 | |
971 | static int | |
972 | show_key_from_file(const char *file, const char *host, int keytype) | |
973 | { | |
974 | Key *found; | |
975 | char *fp; | |
976 | int line, ret; | |
977 | ||
978 | found = key_new(keytype); | |
979 | if ((ret = lookup_key_in_hostfile_by_type(file, host, | |
980 | keytype, found, &line))) { | |
981 | fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX); | |
bbe88b6d | 982 | logit("WARNING: %s key found for host %s\n" |
567a05bf | 983 | "in %s:%d\n" |
8a48a7ef | 984 | "%s key fingerprint %s.", |
985 | key_type(found), host, file, line, | |
986 | key_type(found), fp); | |
987 | xfree(fp); | |
988 | } | |
989 | key_free(found); | |
990 | return (ret); | |
991 | } | |
992 | ||
993 | /* print all known host keys for a given host, but skip keys of given type */ | |
994 | static int | |
995 | show_other_keys(const char *host, Key *key) | |
996 | { | |
997 | int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1}; | |
998 | int i, found = 0; | |
999 | ||
1000 | for (i = 0; type[i] != -1; i++) { | |
1001 | if (type[i] == key->type) | |
1002 | continue; | |
1003 | if (type[i] != KEY_RSA1 && | |
1004 | show_key_from_file(options.user_hostfile2, host, type[i])) { | |
1005 | found = 1; | |
1006 | continue; | |
1007 | } | |
1008 | if (type[i] != KEY_RSA1 && | |
1009 | show_key_from_file(options.system_hostfile2, host, type[i])) { | |
1010 | found = 1; | |
1011 | continue; | |
1012 | } | |
1013 | if (show_key_from_file(options.user_hostfile, host, type[i])) { | |
1014 | found = 1; | |
1015 | continue; | |
1016 | } | |
1017 | if (show_key_from_file(options.system_hostfile, host, type[i])) { | |
1018 | found = 1; | |
1019 | continue; | |
1020 | } | |
1021 | debug2("no key of type %d for host %s", type[i], host); | |
1022 | } | |
1023 | return (found); | |
1024 | } | |
1a1bc5d5 | 1025 | |
1026 | static void | |
1027 | warn_changed_key(Key *host_key) | |
1028 | { | |
1029 | char *fp; | |
f5da7f70 | 1030 | const char *type = key_type(host_key); |
1a1bc5d5 | 1031 | |
1032 | fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX); | |
1033 | ||
1034 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); | |
1035 | error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @"); | |
1036 | error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"); | |
1037 | error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!"); | |
1038 | error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!"); | |
1039 | error("It is also possible that the %s host key has just been changed.", type); | |
1040 | error("The fingerprint for the %s key sent by the remote host is\n%s.", | |
1041 | type, fp); | |
1042 | error("Please contact your system administrator."); | |
1043 | ||
1044 | xfree(fp); | |
1a1bc5d5 | 1045 | } |