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05114c74 | 1 | /*- |
2 | * Copyright (c) 2002 Networks Associates Technology, Inc. | |
3 | * All rights reserved. | |
4 | * | |
5 | * This software was developed for the FreeBSD Project by ThinkSec AS and | |
6 | * NAI Labs, the Security Research Division of Network Associates, Inc. | |
7 | * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the | |
8 | * DARPA CHATS research program. | |
09564242 | 9 | * |
10 | * Redistribution and use in source and binary forms, with or without | |
11 | * modification, are permitted provided that the following conditions | |
12 | * are met: | |
13 | * 1. Redistributions of source code must retain the above copyright | |
14 | * notice, this list of conditions and the following disclaimer. | |
15 | * 2. Redistributions in binary form must reproduce the above copyright | |
16 | * notice, this list of conditions and the following disclaimer in the | |
17 | * documentation and/or other materials provided with the distribution. | |
09564242 | 18 | * |
05114c74 | 19 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE | |
23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
29 | * SUCH DAMAGE. | |
a5c9cd31 | 30 | */ |
31 | ||
5ff453c0 | 32 | /* Based on $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */ |
a5c9cd31 | 33 | #include "includes.h" |
5ff453c0 | 34 | RCSID("$Id$"); |
a5c9cd31 | 35 | |
36 | #ifdef USE_PAM | |
2511d104 | 37 | #if defined(HAVE_SECURITY_PAM_APPL_H) |
05114c74 | 38 | #include <security/pam_appl.h> |
2511d104 | 39 | #elif defined (HAVE_PAM_PAM_APPL_H) |
40 | #include <pam/pam_appl.h> | |
41 | #endif | |
05114c74 | 42 | |
fde58bd4 | 43 | #include "auth.h" |
5c377b3b | 44 | #include "auth-pam.h" |
05114c74 | 45 | #include "buffer.h" |
46 | #include "bufaux.h" | |
42f11eb2 | 47 | #include "canohost.h" |
05114c74 | 48 | #include "log.h" |
49 | #include "monitor_wrap.h" | |
50 | #include "msg.h" | |
51 | #include "packet.h" | |
42f11eb2 | 52 | #include "readpass.h" |
05114c74 | 53 | #include "servconf.h" |
54 | #include "ssh2.h" | |
55 | #include "xmalloc.h" | |
5b9e2464 | 56 | #include "auth-options.h" |
a5c9cd31 | 57 | |
7fceb20d | 58 | extern ServerOptions options; |
3eaf3960 | 59 | extern Buffer loginmsg; |
b3ef7fb7 | 60 | extern int compat20; |
7fceb20d | 61 | |
05114c74 | 62 | #ifdef USE_POSIX_THREADS |
63 | #include <pthread.h> | |
64 | /* | |
aff51935 | 65 | * Avoid namespace clash when *not* using pthreads for systems *with* |
66 | * pthreads, which unconditionally define pthread_t via sys/types.h | |
05114c74 | 67 | * (e.g. Linux) |
68 | */ | |
aff51935 | 69 | typedef pthread_t sp_pthread_t; |
05114c74 | 70 | #else |
e47e681f | 71 | typedef pid_t sp_pthread_t; |
72 | #endif | |
73 | ||
74 | struct pam_ctxt { | |
75 | sp_pthread_t pam_thread; | |
76 | int pam_psock; | |
77 | int pam_csock; | |
78 | int pam_done; | |
79 | }; | |
80 | ||
81 | static void sshpam_free_ctx(void *); | |
82 | static struct pam_ctxt *cleanup_ctxt; | |
83 | ||
84 | #ifndef USE_POSIX_THREADS | |
05114c74 | 85 | /* |
86 | * Simulate threads with processes. | |
87 | */ | |
a5c9cd31 | 88 | |
100e6910 | 89 | static int sshpam_thread_status = -1; |
90 | static mysig_t sshpam_oldsig; | |
91 | ||
92 | static void | |
93 | sshpam_sigchld_handler(int sig) | |
94 | { | |
28b49ff8 | 95 | if (cleanup_ctxt == NULL) |
96 | return; /* handler called after PAM cleanup, shouldn't happen */ | |
100e6910 | 97 | if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0) == -1) |
98 | return; /* couldn't wait for process */ | |
99 | if (WIFSIGNALED(sshpam_thread_status) && | |
100 | WTERMSIG(sshpam_thread_status) == SIGTERM) | |
101 | return; /* terminated by pthread_cancel */ | |
102 | if (!WIFEXITED(sshpam_thread_status)) | |
103 | fatal("PAM: authentication thread exited unexpectedly"); | |
104 | if (WEXITSTATUS(sshpam_thread_status) != 0) | |
105 | fatal("PAM: authentication thread exited uncleanly"); | |
106 | } | |
107 | ||
05114c74 | 108 | static void |
109 | pthread_exit(void *value __unused) | |
110 | { | |
111 | _exit(0); | |
112 | } | |
5daf7064 | 113 | |
05114c74 | 114 | static int |
115 | pthread_create(sp_pthread_t *thread, const void *attr __unused, | |
116 | void *(*thread_start)(void *), void *arg) | |
117 | { | |
118 | pid_t pid; | |
119 | ||
120 | switch ((pid = fork())) { | |
121 | case -1: | |
122 | error("fork(): %s", strerror(errno)); | |
123 | return (-1); | |
124 | case 0: | |
125 | thread_start(arg); | |
126 | _exit(1); | |
127 | default: | |
128 | *thread = pid; | |
100e6910 | 129 | sshpam_oldsig = signal(SIGCHLD, sshpam_sigchld_handler); |
05114c74 | 130 | return (0); |
131 | } | |
132 | } | |
a5c9cd31 | 133 | |
05114c74 | 134 | static int |
135 | pthread_cancel(sp_pthread_t thread) | |
8c9fe09e | 136 | { |
28b49ff8 | 137 | signal(SIGCHLD, sshpam_oldsig); |
05114c74 | 138 | return (kill(thread, SIGTERM)); |
8c9fe09e | 139 | } |
140 | ||
05114c74 | 141 | static int |
142 | pthread_join(sp_pthread_t thread, void **value __unused) | |
8c9fe09e | 143 | { |
05114c74 | 144 | int status; |
145 | ||
100e6910 | 146 | if (sshpam_thread_status != -1) |
147 | return (sshpam_thread_status); | |
148 | signal(SIGCHLD, sshpam_oldsig); | |
05114c74 | 149 | waitpid(thread, &status, 0); |
150 | return (status); | |
8c9fe09e | 151 | } |
05114c74 | 152 | #endif |
153 | ||
154 | ||
0a23d79f | 155 | static pam_handle_t *sshpam_handle = NULL; |
156 | static int sshpam_err = 0; | |
157 | static int sshpam_authenticated = 0; | |
158 | static int sshpam_new_authtok_reqd = 0; | |
159 | static int sshpam_session_open = 0; | |
160 | static int sshpam_cred_established = 0; | |
b3ef7fb7 | 161 | static int sshpam_account_status = -1; |
2212fc98 | 162 | static char **sshpam_env = NULL; |
05114c74 | 163 | |
2212fc98 | 164 | /* Some PAM implementations don't implement this */ |
165 | #ifndef HAVE_PAM_GETENVLIST | |
166 | static char ** | |
167 | pam_getenvlist(pam_handle_t *pamh) | |
168 | { | |
169 | /* | |
aff51935 | 170 | * XXX - If necessary, we can still support envrionment passing |
2212fc98 | 171 | * for platforms without pam_getenvlist by searching for known |
172 | * env vars (e.g. KRB5CCNAME) from the PAM environment. | |
173 | */ | |
174 | return NULL; | |
175 | } | |
176 | #endif | |
177 | ||
b3ef7fb7 | 178 | void |
179 | pam_password_change_required(int reqd) | |
180 | { | |
181 | sshpam_new_authtok_reqd = reqd; | |
182 | if (reqd) { | |
183 | no_port_forwarding_flag |= 2; | |
184 | no_agent_forwarding_flag |= 2; | |
185 | no_x11_forwarding_flag |= 2; | |
186 | } else { | |
187 | no_port_forwarding_flag &= ~2; | |
188 | no_agent_forwarding_flag &= ~2; | |
189 | no_x11_forwarding_flag &= ~2; | |
190 | ||
191 | } | |
192 | } | |
2212fc98 | 193 | /* Import regular and PAM environment from subprocess */ |
194 | static void | |
195 | import_environments(Buffer *b) | |
196 | { | |
197 | char *env; | |
198 | u_int i, num_env; | |
199 | int err; | |
200 | ||
b3ef7fb7 | 201 | /* Import variables set by do_pam_account */ |
202 | sshpam_account_status = buffer_get_int(b); | |
203 | pam_password_change_required(buffer_get_int(b)); | |
204 | ||
2212fc98 | 205 | /* Import environment from subprocess */ |
206 | num_env = buffer_get_int(b); | |
207 | sshpam_env = xmalloc((num_env + 1) * sizeof(*sshpam_env)); | |
208 | debug3("PAM: num env strings %d", num_env); | |
209 | for(i = 0; i < num_env; i++) | |
210 | sshpam_env[i] = buffer_get_string(b, NULL); | |
211 | ||
212 | sshpam_env[num_env] = NULL; | |
213 | ||
214 | /* Import PAM environment from subprocess */ | |
215 | num_env = buffer_get_int(b); | |
216 | debug("PAM: num PAM env strings %d", num_env); | |
217 | for(i = 0; i < num_env; i++) { | |
218 | env = buffer_get_string(b, NULL); | |
219 | ||
f79a6165 | 220 | #ifdef HAVE_PAM_PUTENV |
2212fc98 | 221 | /* Errors are not fatal here */ |
222 | if ((err = pam_putenv(sshpam_handle, env)) != PAM_SUCCESS) { | |
223 | error("PAM: pam_putenv: %s", | |
224 | pam_strerror(sshpam_handle, sshpam_err)); | |
225 | } | |
f79a6165 | 226 | #endif |
2212fc98 | 227 | } |
228 | } | |
229 | ||
ad55cd03 | 230 | /* |
05114c74 | 231 | * Conversation function for authentication thread. |
ad55cd03 | 232 | */ |
05114c74 | 233 | static int |
5b9e2464 | 234 | sshpam_thread_conv(int n, const struct pam_message **msg, |
235 | struct pam_response **resp, void *data) | |
a5c9cd31 | 236 | { |
05114c74 | 237 | Buffer buffer; |
238 | struct pam_ctxt *ctxt; | |
0a23d79f | 239 | struct pam_response *reply; |
05114c74 | 240 | int i; |
241 | ||
0a23d79f | 242 | *resp = NULL; |
243 | ||
05114c74 | 244 | ctxt = data; |
245 | if (n <= 0 || n > PAM_MAX_NUM_MSG) | |
246 | return (PAM_CONV_ERR); | |
0a23d79f | 247 | |
248 | if ((reply = malloc(n * sizeof(*reply))) == NULL) | |
249 | return (PAM_CONV_ERR); | |
250 | memset(reply, 0, n * sizeof(*reply)); | |
251 | ||
05114c74 | 252 | buffer_init(&buffer); |
253 | for (i = 0; i < n; ++i) { | |
05114c74 | 254 | switch (PAM_MSG_MEMBER(msg, i, msg_style)) { |
255 | case PAM_PROMPT_ECHO_OFF: | |
aff51935 | 256 | buffer_put_cstring(&buffer, |
0a23d79f | 257 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 258 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 259 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
260 | goto fail; | |
aff51935 | 261 | if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1) |
7b2a0de3 | 262 | goto fail; |
05114c74 | 263 | if (buffer_get_char(&buffer) != PAM_AUTHTOK) |
264 | goto fail; | |
0a23d79f | 265 | reply[i].resp = buffer_get_string(&buffer, NULL); |
05114c74 | 266 | break; |
267 | case PAM_PROMPT_ECHO_ON: | |
aff51935 | 268 | buffer_put_cstring(&buffer, |
0a23d79f | 269 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 270 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 271 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
272 | goto fail; | |
273 | if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1) | |
274 | goto fail; | |
05114c74 | 275 | if (buffer_get_char(&buffer) != PAM_AUTHTOK) |
276 | goto fail; | |
0a23d79f | 277 | reply[i].resp = buffer_get_string(&buffer, NULL); |
05114c74 | 278 | break; |
279 | case PAM_ERROR_MSG: | |
aff51935 | 280 | buffer_put_cstring(&buffer, |
0a23d79f | 281 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 282 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 283 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
284 | goto fail; | |
05114c74 | 285 | break; |
286 | case PAM_TEXT_INFO: | |
aff51935 | 287 | buffer_put_cstring(&buffer, |
0a23d79f | 288 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 289 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 290 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
291 | goto fail; | |
05114c74 | 292 | break; |
293 | default: | |
294 | goto fail; | |
a5c9cd31 | 295 | } |
05114c74 | 296 | buffer_clear(&buffer); |
a5c9cd31 | 297 | } |
05114c74 | 298 | buffer_free(&buffer); |
0a23d79f | 299 | *resp = reply; |
05114c74 | 300 | return (PAM_SUCCESS); |
0a23d79f | 301 | |
05114c74 | 302 | fail: |
0a23d79f | 303 | for(i = 0; i < n; i++) { |
304 | if (reply[i].resp != NULL) | |
305 | xfree(reply[i].resp); | |
306 | } | |
307 | xfree(reply); | |
05114c74 | 308 | buffer_free(&buffer); |
309 | return (PAM_CONV_ERR); | |
310 | } | |
a5c9cd31 | 311 | |
05114c74 | 312 | /* |
313 | * Authentication thread. | |
314 | */ | |
315 | static void * | |
316 | sshpam_thread(void *ctxtp) | |
317 | { | |
318 | struct pam_ctxt *ctxt = ctxtp; | |
319 | Buffer buffer; | |
c53917a9 | 320 | struct pam_conv sshpam_conv; |
05114c74 | 321 | #ifndef USE_POSIX_THREADS |
2212fc98 | 322 | extern char **environ; |
323 | char **env_from_pam; | |
324 | u_int i; | |
05114c74 | 325 | const char *pam_user; |
326 | ||
327 | pam_get_item(sshpam_handle, PAM_USER, (const void **)&pam_user); | |
328 | setproctitle("%s [pam]", pam_user); | |
2212fc98 | 329 | environ[0] = NULL; |
05114c74 | 330 | #endif |
a5c9cd31 | 331 | |
c53917a9 | 332 | sshpam_conv.conv = sshpam_thread_conv; |
333 | sshpam_conv.appdata_ptr = ctxt; | |
334 | ||
05114c74 | 335 | buffer_init(&buffer); |
336 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, | |
337 | (const void *)&sshpam_conv); | |
338 | if (sshpam_err != PAM_SUCCESS) | |
339 | goto auth_fail; | |
340 | sshpam_err = pam_authenticate(sshpam_handle, 0); | |
341 | if (sshpam_err != PAM_SUCCESS) | |
342 | goto auth_fail; | |
b3ef7fb7 | 343 | |
2935db92 | 344 | if (compat20) { |
b3ef7fb7 | 345 | if (!do_pam_account()) |
346 | goto auth_fail; | |
347 | if (sshpam_new_authtok_reqd) { | |
348 | sshpam_err = pam_chauthtok(sshpam_handle, | |
349 | PAM_CHANGE_EXPIRED_AUTHTOK); | |
350 | if (sshpam_err != PAM_SUCCESS) | |
351 | goto auth_fail; | |
352 | pam_password_change_required(0); | |
353 | } | |
2935db92 | 354 | } |
b3ef7fb7 | 355 | |
05114c74 | 356 | buffer_put_cstring(&buffer, "OK"); |
2212fc98 | 357 | |
358 | #ifndef USE_POSIX_THREADS | |
b3ef7fb7 | 359 | /* Export variables set by do_pam_account */ |
360 | buffer_put_int(&buffer, sshpam_account_status); | |
361 | buffer_put_int(&buffer, sshpam_new_authtok_reqd); | |
362 | ||
2212fc98 | 363 | /* Export any environment strings set in child */ |
364 | for(i = 0; environ[i] != NULL; i++) | |
365 | ; /* Count */ | |
366 | buffer_put_int(&buffer, i); | |
367 | for(i = 0; environ[i] != NULL; i++) | |
368 | buffer_put_cstring(&buffer, environ[i]); | |
369 | ||
370 | /* Export any environment strings set by PAM in child */ | |
371 | env_from_pam = pam_getenvlist(sshpam_handle); | |
372 | for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++) | |
373 | ; /* Count */ | |
374 | buffer_put_int(&buffer, i); | |
375 | for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++) | |
376 | buffer_put_cstring(&buffer, env_from_pam[i]); | |
377 | #endif /* USE_POSIX_THREADS */ | |
378 | ||
7b2a0de3 | 379 | /* XXX - can't do much about an error here */ |
05114c74 | 380 | ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer); |
381 | buffer_free(&buffer); | |
382 | pthread_exit(NULL); | |
383 | ||
384 | auth_fail: | |
385 | buffer_put_cstring(&buffer, | |
386 | pam_strerror(sshpam_handle, sshpam_err)); | |
7b2a0de3 | 387 | /* XXX - can't do much about an error here */ |
05114c74 | 388 | ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer); |
389 | buffer_free(&buffer); | |
390 | pthread_exit(NULL); | |
b6453d99 | 391 | |
05114c74 | 392 | return (NULL); /* Avoid warning for non-pthread case */ |
a5c9cd31 | 393 | } |
394 | ||
c6630044 | 395 | void |
396 | sshpam_thread_cleanup(void) | |
a5c9cd31 | 397 | { |
c6630044 | 398 | struct pam_ctxt *ctxt = cleanup_ctxt; |
399 | ||
400 | if (ctxt != NULL && ctxt->pam_thread != 0) { | |
401 | pthread_cancel(ctxt->pam_thread); | |
402 | pthread_join(ctxt->pam_thread, NULL); | |
403 | close(ctxt->pam_psock); | |
404 | close(ctxt->pam_csock); | |
405 | memset(ctxt, 0, sizeof(*ctxt)); | |
406 | cleanup_ctxt = NULL; | |
407 | } | |
05114c74 | 408 | } |
a5c9cd31 | 409 | |
05114c74 | 410 | static int |
5b9e2464 | 411 | sshpam_null_conv(int n, const struct pam_message **msg, |
412 | struct pam_response **resp, void *data) | |
05114c74 | 413 | { |
05114c74 | 414 | return (PAM_CONV_ERR); |
415 | } | |
a5c9cd31 | 416 | |
05114c74 | 417 | static struct pam_conv null_conv = { sshpam_null_conv, NULL }; |
418 | ||
c6630044 | 419 | void |
420 | sshpam_cleanup(void) | |
05114c74 | 421 | { |
05114c74 | 422 | debug("PAM: cleanup"); |
0a23d79f | 423 | if (sshpam_handle == NULL) |
424 | return; | |
05114c74 | 425 | pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv); |
426 | if (sshpam_cred_established) { | |
427 | pam_setcred(sshpam_handle, PAM_DELETE_CRED); | |
428 | sshpam_cred_established = 0; | |
429 | } | |
430 | if (sshpam_session_open) { | |
431 | pam_close_session(sshpam_handle, PAM_SILENT); | |
432 | sshpam_session_open = 0; | |
a5c9cd31 | 433 | } |
05114c74 | 434 | sshpam_authenticated = sshpam_new_authtok_reqd = 0; |
435 | pam_end(sshpam_handle, sshpam_err); | |
436 | sshpam_handle = NULL; | |
a5c9cd31 | 437 | } |
438 | ||
05114c74 | 439 | static int |
440 | sshpam_init(const char *user) | |
a5c9cd31 | 441 | { |
05114c74 | 442 | extern u_int utmp_len; |
74678fb9 | 443 | extern char *__progname; |
05114c74 | 444 | const char *pam_rhost, *pam_user; |
445 | ||
446 | if (sshpam_handle != NULL) { | |
447 | /* We already have a PAM context; check if the user matches */ | |
448 | sshpam_err = pam_get_item(sshpam_handle, | |
449 | PAM_USER, (const void **)&pam_user); | |
450 | if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0) | |
451 | return (0); | |
05114c74 | 452 | pam_end(sshpam_handle, sshpam_err); |
453 | sshpam_handle = NULL; | |
454 | } | |
455 | debug("PAM: initializing for \"%s\"", user); | |
01224183 | 456 | sshpam_err = |
457 | pam_start(SSHD_PAM_SERVICE, user, &null_conv, &sshpam_handle); | |
5ff453c0 | 458 | if (sshpam_err != PAM_SUCCESS) { |
459 | pam_end(sshpam_handle, sshpam_err); | |
460 | sshpam_handle = NULL; | |
05114c74 | 461 | return (-1); |
5ff453c0 | 462 | } |
c5a7d788 | 463 | pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns); |
05d62329 | 464 | debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost); |
05114c74 | 465 | sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost); |
5ff453c0 | 466 | if (sshpam_err != PAM_SUCCESS) { |
5b9e2464 | 467 | pam_end(sshpam_handle, sshpam_err); |
5ff453c0 | 468 | sshpam_handle = NULL; |
469 | return (-1); | |
470 | } | |
471 | #ifdef PAM_TTY_KLUDGE | |
aff51935 | 472 | /* |
473 | * Some silly PAM modules (e.g. pam_time) require a TTY to operate. | |
474 | * sshd doesn't set the tty until too late in the auth process and | |
5ff453c0 | 475 | * may not even set one (for tty-less connections) |
aff51935 | 476 | */ |
5ff453c0 | 477 | debug("PAM: setting PAM_TTY to \"ssh\""); |
478 | sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, "ssh"); | |
05114c74 | 479 | if (sshpam_err != PAM_SUCCESS) { |
480 | pam_end(sshpam_handle, sshpam_err); | |
481 | sshpam_handle = NULL; | |
482 | return (-1); | |
a5c9cd31 | 483 | } |
5ff453c0 | 484 | #endif |
05114c74 | 485 | return (0); |
a5c9cd31 | 486 | } |
487 | ||
05114c74 | 488 | static void * |
489 | sshpam_init_ctx(Authctxt *authctxt) | |
a5c9cd31 | 490 | { |
05114c74 | 491 | struct pam_ctxt *ctxt; |
492 | int socks[2]; | |
2b87da3b | 493 | |
7fceb20d | 494 | /* Refuse to start if we don't have PAM enabled */ |
495 | if (!options.use_pam) | |
496 | return NULL; | |
497 | ||
05114c74 | 498 | /* Initialize PAM */ |
499 | if (sshpam_init(authctxt->user) == -1) { | |
500 | error("PAM: initialization failed"); | |
501 | return (NULL); | |
502 | } | |
5c377b3b | 503 | |
05114c74 | 504 | ctxt = xmalloc(sizeof *ctxt); |
c6630044 | 505 | memset(ctxt, 0, sizeof(*ctxt)); |
05114c74 | 506 | |
507 | /* Start the authentication thread */ | |
508 | if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) { | |
509 | error("PAM: failed create sockets: %s", strerror(errno)); | |
510 | xfree(ctxt); | |
511 | return (NULL); | |
512 | } | |
513 | ctxt->pam_psock = socks[0]; | |
514 | ctxt->pam_csock = socks[1]; | |
515 | if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) { | |
516 | error("PAM: failed to start authentication thread: %s", | |
517 | strerror(errno)); | |
518 | close(socks[0]); | |
519 | close(socks[1]); | |
520 | xfree(ctxt); | |
521 | return (NULL); | |
a5c9cd31 | 522 | } |
c6630044 | 523 | cleanup_ctxt = ctxt; |
05114c74 | 524 | return (ctxt); |
525 | } | |
a5c9cd31 | 526 | |
05114c74 | 527 | static int |
528 | sshpam_query(void *ctx, char **name, char **info, | |
529 | u_int *num, char ***prompts, u_int **echo_on) | |
530 | { | |
531 | Buffer buffer; | |
532 | struct pam_ctxt *ctxt = ctx; | |
533 | size_t plen; | |
534 | u_char type; | |
535 | char *msg; | |
cbdeccf3 | 536 | size_t len; |
05114c74 | 537 | |
538 | buffer_init(&buffer); | |
539 | *name = xstrdup(""); | |
540 | *info = xstrdup(""); | |
541 | *prompts = xmalloc(sizeof(char *)); | |
542 | **prompts = NULL; | |
543 | plen = 0; | |
544 | *echo_on = xmalloc(sizeof(u_int)); | |
545 | while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) { | |
546 | type = buffer_get_char(&buffer); | |
547 | msg = buffer_get_string(&buffer, NULL); | |
548 | switch (type) { | |
549 | case PAM_PROMPT_ECHO_ON: | |
550 | case PAM_PROMPT_ECHO_OFF: | |
551 | *num = 1; | |
cbdeccf3 | 552 | len = plen + strlen(msg) + 1; |
553 | **prompts = xrealloc(**prompts, len); | |
554 | plen += snprintf(**prompts + plen, len, "%s", msg); | |
05114c74 | 555 | **echo_on = (type == PAM_PROMPT_ECHO_ON); |
556 | xfree(msg); | |
557 | return (0); | |
558 | case PAM_ERROR_MSG: | |
559 | case PAM_TEXT_INFO: | |
560 | /* accumulate messages */ | |
4f1b45b4 | 561 | len = plen + strlen(msg) + 2; |
cbdeccf3 | 562 | **prompts = xrealloc(**prompts, len); |
4f1b45b4 | 563 | plen += snprintf(**prompts + plen, len, "%s\n", msg); |
05114c74 | 564 | xfree(msg); |
5daf7064 | 565 | break; |
05114c74 | 566 | case PAM_SUCCESS: |
567 | case PAM_AUTH_ERR: | |
568 | if (**prompts != NULL) { | |
569 | /* drain any accumulated messages */ | |
3eaf3960 | 570 | debug("PAM: %s", **prompts); |
571 | buffer_append(&loginmsg, **prompts, | |
572 | strlen(**prompts)); | |
05114c74 | 573 | xfree(**prompts); |
574 | **prompts = NULL; | |
575 | } | |
576 | if (type == PAM_SUCCESS) { | |
2212fc98 | 577 | import_environments(&buffer); |
05114c74 | 578 | *num = 0; |
579 | **echo_on = 0; | |
580 | ctxt->pam_done = 1; | |
581 | xfree(msg); | |
582 | return (0); | |
583 | } | |
584 | error("PAM: %s", msg); | |
e250770b | 585 | /* FALLTHROUGH */ |
5daf7064 | 586 | default: |
05114c74 | 587 | *num = 0; |
588 | **echo_on = 0; | |
589 | xfree(msg); | |
590 | ctxt->pam_done = -1; | |
591 | return (-1); | |
592 | } | |
a5c9cd31 | 593 | } |
05114c74 | 594 | return (-1); |
a5c9cd31 | 595 | } |
596 | ||
05114c74 | 597 | /* XXX - see also comment in auth-chall.c:verify_response */ |
598 | static int | |
599 | sshpam_respond(void *ctx, u_int num, char **resp) | |
a5c9cd31 | 600 | { |
05114c74 | 601 | Buffer buffer; |
602 | struct pam_ctxt *ctxt = ctx; | |
603 | ||
604 | debug2("PAM: %s", __func__); | |
605 | switch (ctxt->pam_done) { | |
606 | case 1: | |
607 | sshpam_authenticated = 1; | |
608 | return (0); | |
609 | case 0: | |
610 | break; | |
611 | default: | |
612 | return (-1); | |
a5c9cd31 | 613 | } |
05114c74 | 614 | if (num != 1) { |
615 | error("PAM: expected one response, got %u", num); | |
616 | return (-1); | |
617 | } | |
618 | buffer_init(&buffer); | |
619 | buffer_put_cstring(&buffer, *resp); | |
7b2a0de3 | 620 | if (ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer) == -1) { |
621 | buffer_free(&buffer); | |
622 | return (-1); | |
623 | } | |
05114c74 | 624 | buffer_free(&buffer); |
625 | return (1); | |
a5c9cd31 | 626 | } |
627 | ||
05114c74 | 628 | static void |
629 | sshpam_free_ctx(void *ctxtp) | |
a5c9cd31 | 630 | { |
05114c74 | 631 | struct pam_ctxt *ctxt = ctxtp; |
39ce53de | 632 | |
c6630044 | 633 | sshpam_thread_cleanup(); |
05114c74 | 634 | xfree(ctxt); |
635 | /* | |
636 | * We don't call sshpam_cleanup() here because we may need the PAM | |
637 | * handle at a later stage, e.g. when setting up a session. It's | |
638 | * still on the cleanup list, so pam_end() *will* be called before | |
639 | * the server process terminates. | |
640 | */ | |
ad55cd03 | 641 | } |
642 | ||
05114c74 | 643 | KbdintDevice sshpam_device = { |
644 | "pam", | |
645 | sshpam_init_ctx, | |
646 | sshpam_query, | |
647 | sshpam_respond, | |
648 | sshpam_free_ctx | |
649 | }; | |
650 | ||
651 | KbdintDevice mm_sshpam_device = { | |
652 | "pam", | |
653 | mm_sshpam_init_ctx, | |
654 | mm_sshpam_query, | |
655 | mm_sshpam_respond, | |
656 | mm_sshpam_free_ctx | |
657 | }; | |
2919e060 | 658 | |
2b87da3b | 659 | /* |
05114c74 | 660 | * This replaces auth-pam.c |
ad55cd03 | 661 | */ |
05114c74 | 662 | void |
663 | start_pam(const char *user) | |
ad55cd03 | 664 | { |
817e6d38 | 665 | if (!options.use_pam) |
666 | fatal("PAM: initialisation requested when UsePAM=no"); | |
667 | ||
05114c74 | 668 | if (sshpam_init(user) == -1) |
669 | fatal("PAM: initialisation failed"); | |
a5c9cd31 | 670 | } |
671 | ||
05114c74 | 672 | void |
673 | finish_pam(void) | |
a5c9cd31 | 674 | { |
c6630044 | 675 | sshpam_cleanup(); |
a5c9cd31 | 676 | } |
677 | ||
5b9e2464 | 678 | u_int |
679 | do_pam_account(void) | |
a5c9cd31 | 680 | { |
b3ef7fb7 | 681 | if (sshpam_account_status != -1) |
682 | return (sshpam_account_status); | |
683 | ||
5b9e2464 | 684 | sshpam_err = pam_acct_mgmt(sshpam_handle, 0); |
685 | debug3("%s: pam_acct_mgmt = %d", __func__, sshpam_err); | |
b3ef7fb7 | 686 | |
687 | if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD) { | |
688 | sshpam_account_status = 0; | |
689 | return (sshpam_account_status); | |
5b9e2464 | 690 | } |
691 | ||
b3ef7fb7 | 692 | if (sshpam_err == PAM_NEW_AUTHTOK_REQD) |
693 | pam_password_change_required(1); | |
694 | ||
695 | sshpam_account_status = 1; | |
696 | return (sshpam_account_status); | |
05114c74 | 697 | } |
46c76c63 | 698 | |
49e82bb9 | 699 | void |
700 | do_pam_set_tty(const char *tty) | |
701 | { | |
26b3608b | 702 | if (tty != NULL) { |
703 | debug("PAM: setting PAM_TTY to \"%s\"", tty); | |
704 | sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty); | |
705 | if (sshpam_err != PAM_SUCCESS) | |
706 | fatal("PAM: failed to set PAM_TTY: %s", | |
707 | pam_strerror(sshpam_handle, sshpam_err)); | |
708 | } | |
05114c74 | 709 | } |
cbd7492e | 710 | |
05114c74 | 711 | void |
712 | do_pam_setcred(int init) | |
713 | { | |
714 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, | |
715 | (const void *)&null_conv); | |
716 | if (sshpam_err != PAM_SUCCESS) | |
717 | fatal("PAM: failed to set PAM_CONV: %s", | |
718 | pam_strerror(sshpam_handle, sshpam_err)); | |
719 | if (init) { | |
720 | debug("PAM: establishing credentials"); | |
721 | sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED); | |
722 | } else { | |
723 | debug("PAM: reinitializing credentials"); | |
724 | sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED); | |
725 | } | |
726 | if (sshpam_err == PAM_SUCCESS) { | |
727 | sshpam_cred_established = 1; | |
728 | return; | |
729 | } | |
730 | if (sshpam_authenticated) | |
731 | fatal("PAM: pam_setcred(): %s", | |
732 | pam_strerror(sshpam_handle, sshpam_err)); | |
733 | else | |
734 | debug("PAM: pam_setcred(): %s", | |
735 | pam_strerror(sshpam_handle, sshpam_err)); | |
a5c9cd31 | 736 | } |
737 | ||
05114c74 | 738 | int |
739 | is_pam_password_change_required(void) | |
a5c9cd31 | 740 | { |
05114c74 | 741 | return (sshpam_new_authtok_reqd); |
a5c9cd31 | 742 | } |
743 | ||
05114c74 | 744 | static int |
3eaf3960 | 745 | pam_tty_conv(int n, const struct pam_message **msg, |
5b9e2464 | 746 | struct pam_response **resp, void *data) |
ee48c949 | 747 | { |
05114c74 | 748 | char input[PAM_MAX_MSG_SIZE]; |
0a23d79f | 749 | struct pam_response *reply; |
ee48c949 | 750 | int i; |
751 | ||
0a23d79f | 752 | *resp = NULL; |
753 | ||
3eaf3960 | 754 | if (n <= 0 || n > PAM_MAX_NUM_MSG || !isatty(STDIN_FILENO)) |
05114c74 | 755 | return (PAM_CONV_ERR); |
0a23d79f | 756 | |
757 | if ((reply = malloc(n * sizeof(*reply))) == NULL) | |
758 | return (PAM_CONV_ERR); | |
759 | memset(reply, 0, n * sizeof(*reply)); | |
760 | ||
05114c74 | 761 | for (i = 0; i < n; ++i) { |
762 | switch (PAM_MSG_MEMBER(msg, i, msg_style)) { | |
763 | case PAM_PROMPT_ECHO_OFF: | |
0a23d79f | 764 | reply[i].resp = |
aff51935 | 765 | read_passphrase(PAM_MSG_MEMBER(msg, i, msg), |
05114c74 | 766 | RP_ALLOW_STDIN); |
0a23d79f | 767 | reply[i].resp_retcode = PAM_SUCCESS; |
05114c74 | 768 | break; |
769 | case PAM_PROMPT_ECHO_ON: | |
74117b26 | 770 | fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg)); |
05114c74 | 771 | fgets(input, sizeof input, stdin); |
0a23d79f | 772 | reply[i].resp = xstrdup(input); |
773 | reply[i].resp_retcode = PAM_SUCCESS; | |
05114c74 | 774 | break; |
775 | case PAM_ERROR_MSG: | |
776 | case PAM_TEXT_INFO: | |
74117b26 | 777 | fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg)); |
0a23d79f | 778 | reply[i].resp_retcode = PAM_SUCCESS; |
05114c74 | 779 | break; |
780 | default: | |
781 | goto fail; | |
782 | } | |
ee48c949 | 783 | } |
0a23d79f | 784 | *resp = reply; |
05114c74 | 785 | return (PAM_SUCCESS); |
0a23d79f | 786 | |
05114c74 | 787 | fail: |
0a23d79f | 788 | for(i = 0; i < n; i++) { |
789 | if (reply[i].resp != NULL) | |
790 | xfree(reply[i].resp); | |
791 | } | |
792 | xfree(reply); | |
05114c74 | 793 | return (PAM_CONV_ERR); |
ee48c949 | 794 | } |
795 | ||
3eaf3960 | 796 | static struct pam_conv tty_conv = { pam_tty_conv, NULL }; |
797 | ||
05114c74 | 798 | /* |
799 | * XXX this should be done in the authentication phase, but ssh1 doesn't | |
800 | * support that | |
801 | */ | |
802 | void | |
803 | do_pam_chauthtok(void) | |
a5c9cd31 | 804 | { |
05114c74 | 805 | if (use_privsep) |
5b9e2464 | 806 | fatal("Password expired (unable to change with privsep)"); |
05114c74 | 807 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, |
3eaf3960 | 808 | (const void *)&tty_conv); |
05114c74 | 809 | if (sshpam_err != PAM_SUCCESS) |
810 | fatal("PAM: failed to set PAM_CONV: %s", | |
811 | pam_strerror(sshpam_handle, sshpam_err)); | |
812 | debug("PAM: changing password"); | |
813 | sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK); | |
814 | if (sshpam_err != PAM_SUCCESS) | |
815 | fatal("PAM: pam_chauthtok(): %s", | |
816 | pam_strerror(sshpam_handle, sshpam_err)); | |
5daf7064 | 817 | } |
818 | ||
3eaf3960 | 819 | void |
820 | do_pam_session(void) | |
821 | { | |
aff51935 | 822 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, |
3eaf3960 | 823 | (const void *)&tty_conv); |
824 | if (sshpam_err != PAM_SUCCESS) | |
825 | fatal("PAM: failed to set PAM_CONV: %s", | |
826 | pam_strerror(sshpam_handle, sshpam_err)); | |
827 | sshpam_err = pam_open_session(sshpam_handle, 0); | |
828 | if (sshpam_err != PAM_SUCCESS) | |
829 | fatal("PAM: pam_open_session(): %s", | |
830 | pam_strerror(sshpam_handle, sshpam_err)); | |
831 | sshpam_session_open = 1; | |
832 | } | |
833 | ||
aff51935 | 834 | /* |
749560dd | 835 | * Set a PAM environment string. We need to do this so that the session |
836 | * modules can handle things like Kerberos/GSI credentials that appear | |
837 | * during the ssh authentication process. | |
838 | */ | |
749560dd | 839 | int |
aff51935 | 840 | do_pam_putenv(char *name, char *value) |
749560dd | 841 | { |
749560dd | 842 | int ret = 1; |
b6453d99 | 843 | #ifdef HAVE_PAM_PUTENV |
263c65df | 844 | char *compound; |
845 | size_t len; | |
846 | ||
847 | len = strlen(name) + strlen(value) + 2; | |
848 | compound = xmalloc(len); | |
849 | ||
850 | snprintf(compound, len, "%s=%s", name, value); | |
851 | ret = pam_putenv(sshpam_handle, compound); | |
852 | xfree(compound); | |
749560dd | 853 | #endif |
263c65df | 854 | |
749560dd | 855 | return (ret); |
856 | } | |
857 | ||
05114c74 | 858 | void |
859 | print_pam_messages(void) | |
5daf7064 | 860 | { |
05114c74 | 861 | /* XXX */ |
862 | } | |
2b87da3b | 863 | |
2212fc98 | 864 | char ** |
865 | fetch_pam_child_environment(void) | |
866 | { | |
867 | return sshpam_env; | |
868 | } | |
869 | ||
05114c74 | 870 | char ** |
871 | fetch_pam_environment(void) | |
872 | { | |
05114c74 | 873 | return (pam_getenvlist(sshpam_handle)); |
05114c74 | 874 | } |
5c377b3b | 875 | |
05114c74 | 876 | void |
877 | free_pam_environment(char **env) | |
878 | { | |
879 | char **envp; | |
5daf7064 | 880 | |
0eb6370a | 881 | if (env == NULL) |
882 | return; | |
883 | ||
05114c74 | 884 | for (envp = env; *envp; envp++) |
885 | xfree(*envp); | |
886 | xfree(env); | |
a5c9cd31 | 887 | } |
888 | ||
889 | #endif /* USE_PAM */ |