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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 | */ |
93c5ef94 | 31 | /* |
32 | * Copyright (c) 2003,2004 Damien Miller <djm@mindrot.org> | |
33 | * Copyright (c) 2003,2004 Darren Tucker <dtucker@zip.com.au> | |
34 | * | |
35 | * Permission to use, copy, modify, and distribute this software for any | |
36 | * purpose with or without fee is hereby granted, provided that the above | |
37 | * copyright notice and this permission notice appear in all copies. | |
38 | * | |
39 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | |
40 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | |
41 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR | |
42 | * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | |
43 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN | |
44 | * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF | |
45 | * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. | |
46 | */ | |
a5c9cd31 | 47 | |
5ff453c0 | 48 | /* Based on $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */ |
a5c9cd31 | 49 | #include "includes.h" |
50 | ||
b5b88c19 | 51 | #include <sys/types.h> |
52 | #include <sys/stat.h> | |
53 | #include <sys/wait.h> | |
4352744e | 54 | |
55 | #include <errno.h> | |
b5b88c19 | 56 | #include <signal.h> |
24436b92 | 57 | #include <stdarg.h> |
28cb0a43 | 58 | #include <string.h> |
59 | #include <unistd.h> | |
b5b88c19 | 60 | |
a5c9cd31 | 61 | #ifdef USE_PAM |
2511d104 | 62 | #if defined(HAVE_SECURITY_PAM_APPL_H) |
05114c74 | 63 | #include <security/pam_appl.h> |
2511d104 | 64 | #elif defined (HAVE_PAM_PAM_APPL_H) |
65 | #include <pam/pam_appl.h> | |
66 | #endif | |
05114c74 | 67 | |
44171182 | 68 | /* OpenGroup RFC86.0 and XSSO specify no "const" on arguments */ |
69 | #ifdef PAM_SUN_CODEBASE | |
70 | # define sshpam_const /* Solaris, HP-UX, AIX */ | |
71 | #else | |
72 | # define sshpam_const const /* LinuxPAM, OpenPAM */ | |
73 | #endif | |
74 | ||
8bdc7aa0 | 75 | /* Ambiguity in spec: is it an array of pointers or a pointer to an array? */ |
76 | #ifdef PAM_SUN_CODEBASE | |
77 | # define PAM_MSG_MEMBER(msg, n, member) ((*(msg))[(n)].member) | |
78 | #else | |
79 | # define PAM_MSG_MEMBER(msg, n, member) ((msg)[(n)]->member) | |
80 | #endif | |
81 | ||
00a017bd | 82 | #include "xmalloc.h" |
83 | #include "buffer.h" | |
84 | #include "key.h" | |
85 | #include "hostfile.h" | |
fde58bd4 | 86 | #include "auth.h" |
5c377b3b | 87 | #include "auth-pam.h" |
42f11eb2 | 88 | #include "canohost.h" |
05114c74 | 89 | #include "log.h" |
05114c74 | 90 | #include "msg.h" |
91 | #include "packet.h" | |
0f3ee929 | 92 | #include "misc.h" |
05114c74 | 93 | #include "servconf.h" |
94 | #include "ssh2.h" | |
5b9e2464 | 95 | #include "auth-options.h" |
00a017bd | 96 | #ifdef GSSAPI |
97 | #include "ssh-gss.h" | |
98 | #endif | |
99 | #include "monitor_wrap.h" | |
a5c9cd31 | 100 | |
7fceb20d | 101 | extern ServerOptions options; |
3eaf3960 | 102 | extern Buffer loginmsg; |
b3ef7fb7 | 103 | extern int compat20; |
1e08e787 | 104 | extern u_int utmp_len; |
7fceb20d | 105 | |
b4143b2a | 106 | /* so we don't silently change behaviour */ |
05114c74 | 107 | #ifdef USE_POSIX_THREADS |
b4143b2a | 108 | # error "USE_POSIX_THREADS replaced by UNSUPPORTED_POSIX_THREADS_HACK" |
109 | #endif | |
110 | ||
111 | /* | |
112 | * Formerly known as USE_POSIX_THREADS, using this is completely unsupported | |
113 | * and generally a bad idea. Use at own risk and do not expect support if | |
114 | * this breaks. | |
115 | */ | |
116 | #ifdef UNSUPPORTED_POSIX_THREADS_HACK | |
05114c74 | 117 | #include <pthread.h> |
118 | /* | |
aff51935 | 119 | * Avoid namespace clash when *not* using pthreads for systems *with* |
120 | * pthreads, which unconditionally define pthread_t via sys/types.h | |
05114c74 | 121 | * (e.g. Linux) |
122 | */ | |
aff51935 | 123 | typedef pthread_t sp_pthread_t; |
05114c74 | 124 | #else |
e47e681f | 125 | typedef pid_t sp_pthread_t; |
126 | #endif | |
127 | ||
128 | struct pam_ctxt { | |
129 | sp_pthread_t pam_thread; | |
130 | int pam_psock; | |
131 | int pam_csock; | |
132 | int pam_done; | |
133 | }; | |
134 | ||
135 | static void sshpam_free_ctx(void *); | |
136 | static struct pam_ctxt *cleanup_ctxt; | |
137 | ||
b4143b2a | 138 | #ifndef UNSUPPORTED_POSIX_THREADS_HACK |
05114c74 | 139 | /* |
140 | * Simulate threads with processes. | |
141 | */ | |
a5c9cd31 | 142 | |
100e6910 | 143 | static int sshpam_thread_status = -1; |
144 | static mysig_t sshpam_oldsig; | |
145 | ||
d1cf9a87 | 146 | static void |
100e6910 | 147 | sshpam_sigchld_handler(int sig) |
148 | { | |
8a956cda | 149 | signal(SIGCHLD, SIG_DFL); |
28b49ff8 | 150 | if (cleanup_ctxt == NULL) |
151 | return; /* handler called after PAM cleanup, shouldn't happen */ | |
8a956cda | 152 | if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, WNOHANG) |
ed9e8be3 | 153 | <= 0) { |
8a956cda | 154 | /* PAM thread has not exitted, privsep slave must have */ |
155 | kill(cleanup_ctxt->pam_thread, SIGTERM); | |
156 | if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0) | |
930d0441 | 157 | <= 0) |
8a956cda | 158 | return; /* could not wait */ |
159 | } | |
100e6910 | 160 | if (WIFSIGNALED(sshpam_thread_status) && |
161 | WTERMSIG(sshpam_thread_status) == SIGTERM) | |
162 | return; /* terminated by pthread_cancel */ | |
163 | if (!WIFEXITED(sshpam_thread_status)) | |
164 | fatal("PAM: authentication thread exited unexpectedly"); | |
165 | if (WEXITSTATUS(sshpam_thread_status) != 0) | |
166 | fatal("PAM: authentication thread exited uncleanly"); | |
167 | } | |
168 | ||
28cb0a43 | 169 | /* ARGSUSED */ |
05114c74 | 170 | static void |
28cb0a43 | 171 | pthread_exit(void *value) |
05114c74 | 172 | { |
173 | _exit(0); | |
174 | } | |
5daf7064 | 175 | |
28cb0a43 | 176 | /* ARGSUSED */ |
05114c74 | 177 | static int |
28cb0a43 | 178 | pthread_create(sp_pthread_t *thread, const void *attr, |
05114c74 | 179 | void *(*thread_start)(void *), void *arg) |
180 | { | |
181 | pid_t pid; | |
5d001c70 | 182 | struct pam_ctxt *ctx = arg; |
05114c74 | 183 | |
355fbf31 | 184 | sshpam_thread_status = -1; |
05114c74 | 185 | switch ((pid = fork())) { |
186 | case -1: | |
187 | error("fork(): %s", strerror(errno)); | |
188 | return (-1); | |
189 | case 0: | |
5d001c70 | 190 | close(ctx->pam_psock); |
191 | ctx->pam_psock = -1; | |
05114c74 | 192 | thread_start(arg); |
193 | _exit(1); | |
194 | default: | |
195 | *thread = pid; | |
5d001c70 | 196 | close(ctx->pam_csock); |
197 | ctx->pam_csock = -1; | |
100e6910 | 198 | sshpam_oldsig = signal(SIGCHLD, sshpam_sigchld_handler); |
05114c74 | 199 | return (0); |
200 | } | |
201 | } | |
a5c9cd31 | 202 | |
05114c74 | 203 | static int |
204 | pthread_cancel(sp_pthread_t thread) | |
8c9fe09e | 205 | { |
28b49ff8 | 206 | signal(SIGCHLD, sshpam_oldsig); |
05114c74 | 207 | return (kill(thread, SIGTERM)); |
8c9fe09e | 208 | } |
209 | ||
28cb0a43 | 210 | /* ARGSUSED */ |
05114c74 | 211 | static int |
28cb0a43 | 212 | pthread_join(sp_pthread_t thread, void **value) |
8c9fe09e | 213 | { |
05114c74 | 214 | int status; |
215 | ||
100e6910 | 216 | if (sshpam_thread_status != -1) |
217 | return (sshpam_thread_status); | |
218 | signal(SIGCHLD, sshpam_oldsig); | |
05114c74 | 219 | waitpid(thread, &status, 0); |
220 | return (status); | |
8c9fe09e | 221 | } |
05114c74 | 222 | #endif |
223 | ||
224 | ||
0a23d79f | 225 | static pam_handle_t *sshpam_handle = NULL; |
226 | static int sshpam_err = 0; | |
227 | static int sshpam_authenticated = 0; | |
0a23d79f | 228 | static int sshpam_session_open = 0; |
229 | static int sshpam_cred_established = 0; | |
b3ef7fb7 | 230 | static int sshpam_account_status = -1; |
2212fc98 | 231 | static char **sshpam_env = NULL; |
d948154a | 232 | static Authctxt *sshpam_authctxt = NULL; |
5de92f17 | 233 | static const char *sshpam_password = NULL; |
af0e5c2f | 234 | static char badpw[] = "\b\n\r\177INCORRECT"; |
05114c74 | 235 | |
2212fc98 | 236 | /* Some PAM implementations don't implement this */ |
237 | #ifndef HAVE_PAM_GETENVLIST | |
238 | static char ** | |
239 | pam_getenvlist(pam_handle_t *pamh) | |
240 | { | |
241 | /* | |
aff51935 | 242 | * XXX - If necessary, we can still support envrionment passing |
2212fc98 | 243 | * for platforms without pam_getenvlist by searching for known |
244 | * env vars (e.g. KRB5CCNAME) from the PAM environment. | |
245 | */ | |
246 | return NULL; | |
247 | } | |
248 | #endif | |
249 | ||
059d3165 | 250 | /* |
251 | * Some platforms, notably Solaris, do not enforce password complexity | |
252 | * rules during pam_chauthtok() if the real uid of the calling process | |
253 | * is 0, on the assumption that it's being called by "passwd" run by root. | |
254 | * This wraps pam_chauthtok and sets/restore the real uid so PAM will do | |
255 | * the right thing. | |
256 | */ | |
257 | #ifdef SSHPAM_CHAUTHTOK_NEEDS_RUID | |
258 | static int | |
259 | sshpam_chauthtok_ruid(pam_handle_t *pamh, int flags) | |
260 | { | |
261 | int result; | |
262 | ||
263 | if (sshpam_authctxt == NULL) | |
264 | fatal("PAM: sshpam_authctxt not initialized"); | |
265 | if (setreuid(sshpam_authctxt->pw->pw_uid, -1) == -1) | |
266 | fatal("%s: setreuid failed: %s", __func__, strerror(errno)); | |
267 | result = pam_chauthtok(pamh, flags); | |
268 | if (setreuid(0, -1) == -1) | |
269 | fatal("%s: setreuid failed: %s", __func__, strerror(errno)); | |
270 | return result; | |
271 | } | |
272 | # define pam_chauthtok(a,b) (sshpam_chauthtok_ruid((a), (b))) | |
273 | #endif | |
274 | ||
b3ef7fb7 | 275 | void |
c10bb2ce | 276 | sshpam_password_change_required(int reqd) |
b3ef7fb7 | 277 | { |
90f3c272 | 278 | debug3("%s %d", __func__, reqd); |
d948154a | 279 | if (sshpam_authctxt == NULL) |
529d73ab | 280 | fatal("%s: PAM authctxt not initialized", __func__); |
d948154a | 281 | sshpam_authctxt->force_pwchange = reqd; |
b3ef7fb7 | 282 | if (reqd) { |
283 | no_port_forwarding_flag |= 2; | |
284 | no_agent_forwarding_flag |= 2; | |
285 | no_x11_forwarding_flag |= 2; | |
286 | } else { | |
287 | no_port_forwarding_flag &= ~2; | |
288 | no_agent_forwarding_flag &= ~2; | |
289 | no_x11_forwarding_flag &= ~2; | |
b3ef7fb7 | 290 | } |
291 | } | |
dd1fb864 | 292 | |
2212fc98 | 293 | /* Import regular and PAM environment from subprocess */ |
294 | static void | |
295 | import_environments(Buffer *b) | |
296 | { | |
297 | char *env; | |
298 | u_int i, num_env; | |
299 | int err; | |
300 | ||
90f3c272 | 301 | debug3("PAM: %s entering", __func__); |
302 | ||
b4143b2a | 303 | #ifndef UNSUPPORTED_POSIX_THREADS_HACK |
b3ef7fb7 | 304 | /* Import variables set by do_pam_account */ |
305 | sshpam_account_status = buffer_get_int(b); | |
c10bb2ce | 306 | sshpam_password_change_required(buffer_get_int(b)); |
b3ef7fb7 | 307 | |
2212fc98 | 308 | /* Import environment from subprocess */ |
309 | num_env = buffer_get_int(b); | |
01d35895 | 310 | if (num_env > 1024) |
311 | fatal("%s: received %u environment variables, expected <= 1024", | |
312 | __func__, num_env); | |
313 | sshpam_env = xcalloc(num_env + 1, sizeof(*sshpam_env)); | |
2212fc98 | 314 | debug3("PAM: num env strings %d", num_env); |
315 | for(i = 0; i < num_env; i++) | |
316 | sshpam_env[i] = buffer_get_string(b, NULL); | |
317 | ||
318 | sshpam_env[num_env] = NULL; | |
319 | ||
320 | /* Import PAM environment from subprocess */ | |
321 | num_env = buffer_get_int(b); | |
322 | debug("PAM: num PAM env strings %d", num_env); | |
323 | for(i = 0; i < num_env; i++) { | |
324 | env = buffer_get_string(b, NULL); | |
325 | ||
f79a6165 | 326 | #ifdef HAVE_PAM_PUTENV |
2212fc98 | 327 | /* Errors are not fatal here */ |
328 | if ((err = pam_putenv(sshpam_handle, env)) != PAM_SUCCESS) { | |
329 | error("PAM: pam_putenv: %s", | |
330 | pam_strerror(sshpam_handle, sshpam_err)); | |
331 | } | |
f79a6165 | 332 | #endif |
2212fc98 | 333 | } |
a1e0095d | 334 | #endif |
2212fc98 | 335 | } |
336 | ||
ad55cd03 | 337 | /* |
05114c74 | 338 | * Conversation function for authentication thread. |
ad55cd03 | 339 | */ |
05114c74 | 340 | static int |
44171182 | 341 | sshpam_thread_conv(int n, sshpam_const struct pam_message **msg, |
5b9e2464 | 342 | struct pam_response **resp, void *data) |
a5c9cd31 | 343 | { |
05114c74 | 344 | Buffer buffer; |
345 | struct pam_ctxt *ctxt; | |
0a23d79f | 346 | struct pam_response *reply; |
05114c74 | 347 | int i; |
348 | ||
60922169 | 349 | debug3("PAM: %s entering, %d messages", __func__, n); |
0a23d79f | 350 | *resp = NULL; |
351 | ||
d506e25f | 352 | if (data == NULL) { |
353 | error("PAM: conversation function passed a null context"); | |
354 | return (PAM_CONV_ERR); | |
355 | } | |
05114c74 | 356 | ctxt = data; |
357 | if (n <= 0 || n > PAM_MAX_NUM_MSG) | |
358 | return (PAM_CONV_ERR); | |
0a23d79f | 359 | |
01d35895 | 360 | if ((reply = calloc(n, sizeof(*reply))) == NULL) |
0a23d79f | 361 | return (PAM_CONV_ERR); |
0a23d79f | 362 | |
05114c74 | 363 | buffer_init(&buffer); |
364 | for (i = 0; i < n; ++i) { | |
05114c74 | 365 | switch (PAM_MSG_MEMBER(msg, i, msg_style)) { |
366 | case PAM_PROMPT_ECHO_OFF: | |
aff51935 | 367 | buffer_put_cstring(&buffer, |
0a23d79f | 368 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 369 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 370 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
371 | goto fail; | |
aff51935 | 372 | if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1) |
7b2a0de3 | 373 | goto fail; |
05114c74 | 374 | if (buffer_get_char(&buffer) != PAM_AUTHTOK) |
375 | goto fail; | |
0a23d79f | 376 | reply[i].resp = buffer_get_string(&buffer, NULL); |
05114c74 | 377 | break; |
378 | case PAM_PROMPT_ECHO_ON: | |
aff51935 | 379 | buffer_put_cstring(&buffer, |
0a23d79f | 380 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 381 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 382 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
383 | goto fail; | |
384 | if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1) | |
385 | goto fail; | |
05114c74 | 386 | if (buffer_get_char(&buffer) != PAM_AUTHTOK) |
387 | goto fail; | |
0a23d79f | 388 | reply[i].resp = buffer_get_string(&buffer, NULL); |
05114c74 | 389 | break; |
390 | case PAM_ERROR_MSG: | |
aff51935 | 391 | buffer_put_cstring(&buffer, |
0a23d79f | 392 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 393 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 394 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
395 | goto fail; | |
05114c74 | 396 | break; |
397 | case PAM_TEXT_INFO: | |
aff51935 | 398 | buffer_put_cstring(&buffer, |
0a23d79f | 399 | PAM_MSG_MEMBER(msg, i, msg)); |
aff51935 | 400 | if (ssh_msg_send(ctxt->pam_csock, |
7b2a0de3 | 401 | PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1) |
402 | goto fail; | |
05114c74 | 403 | break; |
404 | default: | |
405 | goto fail; | |
a5c9cd31 | 406 | } |
05114c74 | 407 | buffer_clear(&buffer); |
a5c9cd31 | 408 | } |
05114c74 | 409 | buffer_free(&buffer); |
0a23d79f | 410 | *resp = reply; |
05114c74 | 411 | return (PAM_SUCCESS); |
0a23d79f | 412 | |
05114c74 | 413 | fail: |
0a23d79f | 414 | for(i = 0; i < n; i++) { |
415 | if (reply[i].resp != NULL) | |
416 | xfree(reply[i].resp); | |
417 | } | |
418 | xfree(reply); | |
05114c74 | 419 | buffer_free(&buffer); |
420 | return (PAM_CONV_ERR); | |
421 | } | |
a5c9cd31 | 422 | |
05114c74 | 423 | /* |
424 | * Authentication thread. | |
425 | */ | |
426 | static void * | |
427 | sshpam_thread(void *ctxtp) | |
428 | { | |
429 | struct pam_ctxt *ctxt = ctxtp; | |
430 | Buffer buffer; | |
c53917a9 | 431 | struct pam_conv sshpam_conv; |
e4472e7e | 432 | int flags = (options.permit_empty_passwd == 0 ? |
433 | PAM_DISALLOW_NULL_AUTHTOK : 0); | |
b4143b2a | 434 | #ifndef UNSUPPORTED_POSIX_THREADS_HACK |
2212fc98 | 435 | extern char **environ; |
436 | char **env_from_pam; | |
437 | u_int i; | |
05114c74 | 438 | const char *pam_user; |
44171182 | 439 | const char **ptr_pam_user = &pam_user; |
05114c74 | 440 | |
44171182 | 441 | pam_get_item(sshpam_handle, PAM_USER, |
442 | (sshpam_const void **)ptr_pam_user); | |
2212fc98 | 443 | environ[0] = NULL; |
da97d54d | 444 | |
445 | if (sshpam_authctxt != NULL) { | |
446 | setproctitle("%s [pam]", | |
447 | sshpam_authctxt->valid ? pam_user : "unknown"); | |
448 | } | |
05114c74 | 449 | #endif |
a5c9cd31 | 450 | |
c53917a9 | 451 | sshpam_conv.conv = sshpam_thread_conv; |
452 | sshpam_conv.appdata_ptr = ctxt; | |
453 | ||
d948154a | 454 | if (sshpam_authctxt == NULL) |
529d73ab | 455 | fatal("%s: PAM authctxt not initialized", __func__); |
456 | ||
05114c74 | 457 | buffer_init(&buffer); |
458 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, | |
459 | (const void *)&sshpam_conv); | |
460 | if (sshpam_err != PAM_SUCCESS) | |
461 | goto auth_fail; | |
e4472e7e | 462 | sshpam_err = pam_authenticate(sshpam_handle, flags); |
05114c74 | 463 | if (sshpam_err != PAM_SUCCESS) |
464 | goto auth_fail; | |
b3ef7fb7 | 465 | |
2935db92 | 466 | if (compat20) { |
5aa56df0 | 467 | if (!do_pam_account()) { |
468 | sshpam_err = PAM_ACCT_EXPIRED; | |
b3ef7fb7 | 469 | goto auth_fail; |
5aa56df0 | 470 | } |
d948154a | 471 | if (sshpam_authctxt->force_pwchange) { |
b3ef7fb7 | 472 | sshpam_err = pam_chauthtok(sshpam_handle, |
473 | PAM_CHANGE_EXPIRED_AUTHTOK); | |
474 | if (sshpam_err != PAM_SUCCESS) | |
475 | goto auth_fail; | |
c10bb2ce | 476 | sshpam_password_change_required(0); |
b3ef7fb7 | 477 | } |
2935db92 | 478 | } |
b3ef7fb7 | 479 | |
05114c74 | 480 | buffer_put_cstring(&buffer, "OK"); |
2212fc98 | 481 | |
b4143b2a | 482 | #ifndef UNSUPPORTED_POSIX_THREADS_HACK |
b3ef7fb7 | 483 | /* Export variables set by do_pam_account */ |
484 | buffer_put_int(&buffer, sshpam_account_status); | |
d948154a | 485 | buffer_put_int(&buffer, sshpam_authctxt->force_pwchange); |
b3ef7fb7 | 486 | |
2212fc98 | 487 | /* Export any environment strings set in child */ |
488 | for(i = 0; environ[i] != NULL; i++) | |
489 | ; /* Count */ | |
490 | buffer_put_int(&buffer, i); | |
491 | for(i = 0; environ[i] != NULL; i++) | |
492 | buffer_put_cstring(&buffer, environ[i]); | |
493 | ||
494 | /* Export any environment strings set by PAM in child */ | |
495 | env_from_pam = pam_getenvlist(sshpam_handle); | |
496 | for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++) | |
497 | ; /* Count */ | |
498 | buffer_put_int(&buffer, i); | |
499 | for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++) | |
500 | buffer_put_cstring(&buffer, env_from_pam[i]); | |
b4143b2a | 501 | #endif /* UNSUPPORTED_POSIX_THREADS_HACK */ |
2212fc98 | 502 | |
7b2a0de3 | 503 | /* XXX - can't do much about an error here */ |
05114c74 | 504 | ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer); |
505 | buffer_free(&buffer); | |
506 | pthread_exit(NULL); | |
507 | ||
508 | auth_fail: | |
509 | buffer_put_cstring(&buffer, | |
510 | pam_strerror(sshpam_handle, sshpam_err)); | |
7b2a0de3 | 511 | /* XXX - can't do much about an error here */ |
5aa56df0 | 512 | if (sshpam_err == PAM_ACCT_EXPIRED) |
513 | ssh_msg_send(ctxt->pam_csock, PAM_ACCT_EXPIRED, &buffer); | |
514 | else | |
515 | ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer); | |
05114c74 | 516 | buffer_free(&buffer); |
517 | pthread_exit(NULL); | |
b6453d99 | 518 | |
05114c74 | 519 | return (NULL); /* Avoid warning for non-pthread case */ |
a5c9cd31 | 520 | } |
521 | ||
c6630044 | 522 | void |
523 | sshpam_thread_cleanup(void) | |
a5c9cd31 | 524 | { |
c6630044 | 525 | struct pam_ctxt *ctxt = cleanup_ctxt; |
526 | ||
90f3c272 | 527 | debug3("PAM: %s entering", __func__); |
c6630044 | 528 | if (ctxt != NULL && ctxt->pam_thread != 0) { |
529 | pthread_cancel(ctxt->pam_thread); | |
530 | pthread_join(ctxt->pam_thread, NULL); | |
531 | close(ctxt->pam_psock); | |
532 | close(ctxt->pam_csock); | |
533 | memset(ctxt, 0, sizeof(*ctxt)); | |
534 | cleanup_ctxt = NULL; | |
535 | } | |
05114c74 | 536 | } |
a5c9cd31 | 537 | |
05114c74 | 538 | static int |
44171182 | 539 | sshpam_null_conv(int n, sshpam_const struct pam_message **msg, |
5b9e2464 | 540 | struct pam_response **resp, void *data) |
05114c74 | 541 | { |
60922169 | 542 | debug3("PAM: %s entering, %d messages", __func__, n); |
05114c74 | 543 | return (PAM_CONV_ERR); |
544 | } | |
a5c9cd31 | 545 | |
05114c74 | 546 | static struct pam_conv null_conv = { sshpam_null_conv, NULL }; |
547 | ||
ab17aac2 | 548 | static int |
44171182 | 549 | sshpam_store_conv(int n, sshpam_const struct pam_message **msg, |
ab17aac2 | 550 | struct pam_response **resp, void *data) |
551 | { | |
552 | struct pam_response *reply; | |
553 | int i; | |
554 | size_t len; | |
555 | ||
556 | debug3("PAM: %s called with %d messages", __func__, n); | |
557 | *resp = NULL; | |
558 | ||
559 | if (n <= 0 || n > PAM_MAX_NUM_MSG) | |
560 | return (PAM_CONV_ERR); | |
561 | ||
01d35895 | 562 | if ((reply = calloc(n, sizeof(*reply))) == NULL) |
ab17aac2 | 563 | return (PAM_CONV_ERR); |
ab17aac2 | 564 | |
565 | for (i = 0; i < n; ++i) { | |
566 | switch (PAM_MSG_MEMBER(msg, i, msg_style)) { | |
567 | case PAM_ERROR_MSG: | |
568 | case PAM_TEXT_INFO: | |
569 | len = strlen(PAM_MSG_MEMBER(msg, i, msg)); | |
570 | buffer_append(&loginmsg, PAM_MSG_MEMBER(msg, i, msg), len); | |
571 | buffer_append(&loginmsg, "\n", 1 ); | |
572 | reply[i].resp_retcode = PAM_SUCCESS; | |
573 | break; | |
574 | default: | |
575 | goto fail; | |
576 | } | |
577 | } | |
578 | *resp = reply; | |
579 | return (PAM_SUCCESS); | |
580 | ||
581 | fail: | |
582 | for(i = 0; i < n; i++) { | |
583 | if (reply[i].resp != NULL) | |
584 | xfree(reply[i].resp); | |
585 | } | |
586 | xfree(reply); | |
587 | return (PAM_CONV_ERR); | |
588 | } | |
589 | ||
590 | static struct pam_conv store_conv = { sshpam_store_conv, NULL }; | |
591 | ||
c6630044 | 592 | void |
593 | sshpam_cleanup(void) | |
05114c74 | 594 | { |
05114c74 | 595 | debug("PAM: cleanup"); |
0a23d79f | 596 | if (sshpam_handle == NULL) |
597 | return; | |
05114c74 | 598 | pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv); |
599 | if (sshpam_cred_established) { | |
600 | pam_setcred(sshpam_handle, PAM_DELETE_CRED); | |
601 | sshpam_cred_established = 0; | |
602 | } | |
603 | if (sshpam_session_open) { | |
604 | pam_close_session(sshpam_handle, PAM_SILENT); | |
605 | sshpam_session_open = 0; | |
a5c9cd31 | 606 | } |
dd1fb864 | 607 | sshpam_authenticated = 0; |
05114c74 | 608 | pam_end(sshpam_handle, sshpam_err); |
609 | sshpam_handle = NULL; | |
a5c9cd31 | 610 | } |
611 | ||
05114c74 | 612 | static int |
529d73ab | 613 | sshpam_init(Authctxt *authctxt) |
a5c9cd31 | 614 | { |
74678fb9 | 615 | extern char *__progname; |
529d73ab | 616 | const char *pam_rhost, *pam_user, *user = authctxt->user; |
44171182 | 617 | const char **ptr_pam_user = &pam_user; |
05114c74 | 618 | |
619 | if (sshpam_handle != NULL) { | |
620 | /* We already have a PAM context; check if the user matches */ | |
621 | sshpam_err = pam_get_item(sshpam_handle, | |
44171182 | 622 | PAM_USER, (sshpam_const void **)ptr_pam_user); |
05114c74 | 623 | if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0) |
624 | return (0); | |
05114c74 | 625 | pam_end(sshpam_handle, sshpam_err); |
626 | sshpam_handle = NULL; | |
627 | } | |
628 | debug("PAM: initializing for \"%s\"", user); | |
01224183 | 629 | sshpam_err = |
ba6dd90e | 630 | pam_start(SSHD_PAM_SERVICE, user, &store_conv, &sshpam_handle); |
d948154a | 631 | sshpam_authctxt = authctxt; |
529d73ab | 632 | |
5ff453c0 | 633 | if (sshpam_err != PAM_SUCCESS) { |
634 | pam_end(sshpam_handle, sshpam_err); | |
635 | sshpam_handle = NULL; | |
05114c74 | 636 | return (-1); |
5ff453c0 | 637 | } |
c5a7d788 | 638 | pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns); |
05d62329 | 639 | debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost); |
05114c74 | 640 | sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost); |
5ff453c0 | 641 | if (sshpam_err != PAM_SUCCESS) { |
5b9e2464 | 642 | pam_end(sshpam_handle, sshpam_err); |
5ff453c0 | 643 | sshpam_handle = NULL; |
644 | return (-1); | |
645 | } | |
646 | #ifdef PAM_TTY_KLUDGE | |
aff51935 | 647 | /* |
648 | * Some silly PAM modules (e.g. pam_time) require a TTY to operate. | |
649 | * sshd doesn't set the tty until too late in the auth process and | |
5ff453c0 | 650 | * may not even set one (for tty-less connections) |
aff51935 | 651 | */ |
5ff453c0 | 652 | debug("PAM: setting PAM_TTY to \"ssh\""); |
653 | sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, "ssh"); | |
05114c74 | 654 | if (sshpam_err != PAM_SUCCESS) { |
655 | pam_end(sshpam_handle, sshpam_err); | |
656 | sshpam_handle = NULL; | |
657 | return (-1); | |
a5c9cd31 | 658 | } |
5ff453c0 | 659 | #endif |
05114c74 | 660 | return (0); |
a5c9cd31 | 661 | } |
662 | ||
05114c74 | 663 | static void * |
664 | sshpam_init_ctx(Authctxt *authctxt) | |
a5c9cd31 | 665 | { |
05114c74 | 666 | struct pam_ctxt *ctxt; |
667 | int socks[2]; | |
2b87da3b | 668 | |
90f3c272 | 669 | debug3("PAM: %s entering", __func__); |
5aa56df0 | 670 | /* |
671 | * Refuse to start if we don't have PAM enabled or do_pam_account | |
672 | * has previously failed. | |
673 | */ | |
674 | if (!options.use_pam || sshpam_account_status == 0) | |
7fceb20d | 675 | return NULL; |
676 | ||
05114c74 | 677 | /* Initialize PAM */ |
529d73ab | 678 | if (sshpam_init(authctxt) == -1) { |
05114c74 | 679 | error("PAM: initialization failed"); |
680 | return (NULL); | |
681 | } | |
5c377b3b | 682 | |
05114c74 | 683 | ctxt = xmalloc(sizeof *ctxt); |
c6630044 | 684 | memset(ctxt, 0, sizeof(*ctxt)); |
05114c74 | 685 | |
686 | /* Start the authentication thread */ | |
687 | if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) { | |
688 | error("PAM: failed create sockets: %s", strerror(errno)); | |
689 | xfree(ctxt); | |
690 | return (NULL); | |
691 | } | |
692 | ctxt->pam_psock = socks[0]; | |
693 | ctxt->pam_csock = socks[1]; | |
694 | if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) { | |
695 | error("PAM: failed to start authentication thread: %s", | |
696 | strerror(errno)); | |
697 | close(socks[0]); | |
698 | close(socks[1]); | |
699 | xfree(ctxt); | |
700 | return (NULL); | |
a5c9cd31 | 701 | } |
c6630044 | 702 | cleanup_ctxt = ctxt; |
05114c74 | 703 | return (ctxt); |
704 | } | |
a5c9cd31 | 705 | |
05114c74 | 706 | static int |
707 | sshpam_query(void *ctx, char **name, char **info, | |
708 | u_int *num, char ***prompts, u_int **echo_on) | |
709 | { | |
710 | Buffer buffer; | |
711 | struct pam_ctxt *ctxt = ctx; | |
712 | size_t plen; | |
713 | u_char type; | |
714 | char *msg; | |
bbe58934 | 715 | size_t len, mlen; |
05114c74 | 716 | |
90f3c272 | 717 | debug3("PAM: %s entering", __func__); |
05114c74 | 718 | buffer_init(&buffer); |
719 | *name = xstrdup(""); | |
720 | *info = xstrdup(""); | |
721 | *prompts = xmalloc(sizeof(char *)); | |
722 | **prompts = NULL; | |
723 | plen = 0; | |
724 | *echo_on = xmalloc(sizeof(u_int)); | |
725 | while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) { | |
726 | type = buffer_get_char(&buffer); | |
727 | msg = buffer_get_string(&buffer, NULL); | |
bbe58934 | 728 | mlen = strlen(msg); |
05114c74 | 729 | switch (type) { |
730 | case PAM_PROMPT_ECHO_ON: | |
731 | case PAM_PROMPT_ECHO_OFF: | |
732 | *num = 1; | |
bbe58934 | 733 | len = plen + mlen + 1; |
c5d10563 | 734 | **prompts = xrealloc(**prompts, 1, len); |
bbe58934 | 735 | strlcpy(**prompts + plen, msg, len - plen); |
736 | plen += mlen; | |
05114c74 | 737 | **echo_on = (type == PAM_PROMPT_ECHO_ON); |
738 | xfree(msg); | |
739 | return (0); | |
740 | case PAM_ERROR_MSG: | |
741 | case PAM_TEXT_INFO: | |
742 | /* accumulate messages */ | |
bbe58934 | 743 | len = plen + mlen + 2; |
c5d10563 | 744 | **prompts = xrealloc(**prompts, 1, len); |
bbe58934 | 745 | strlcpy(**prompts + plen, msg, len - plen); |
746 | plen += mlen; | |
747 | strlcat(**prompts + plen, "\n", len - plen); | |
748 | plen++; | |
05114c74 | 749 | xfree(msg); |
5daf7064 | 750 | break; |
5aa56df0 | 751 | case PAM_ACCT_EXPIRED: |
752 | sshpam_account_status = 0; | |
753 | /* FALLTHROUGH */ | |
05114c74 | 754 | case PAM_AUTH_ERR: |
5aa56df0 | 755 | debug3("PAM: %s", pam_strerror(sshpam_handle, type)); |
cafa6a80 | 756 | if (**prompts != NULL && strlen(**prompts) != 0) { |
757 | *info = **prompts; | |
758 | **prompts = NULL; | |
759 | *num = 0; | |
760 | **echo_on = 0; | |
761 | ctxt->pam_done = -1; | |
08a3f952 | 762 | xfree(msg); |
cafa6a80 | 763 | return 0; |
764 | } | |
765 | /* FALLTHROUGH */ | |
766 | case PAM_SUCCESS: | |
05114c74 | 767 | if (**prompts != NULL) { |
768 | /* drain any accumulated messages */ | |
3eaf3960 | 769 | debug("PAM: %s", **prompts); |
770 | buffer_append(&loginmsg, **prompts, | |
771 | strlen(**prompts)); | |
05114c74 | 772 | xfree(**prompts); |
773 | **prompts = NULL; | |
774 | } | |
775 | if (type == PAM_SUCCESS) { | |
2d5104e2 | 776 | if (!sshpam_authctxt->valid || |
777 | (sshpam_authctxt->pw->pw_uid == 0 && | |
778 | options.permit_root_login != PERMIT_YES)) | |
af0e5c2f | 779 | fatal("Internal error: PAM auth " |
780 | "succeeded when it should have " | |
781 | "failed"); | |
2212fc98 | 782 | import_environments(&buffer); |
05114c74 | 783 | *num = 0; |
784 | **echo_on = 0; | |
785 | ctxt->pam_done = 1; | |
786 | xfree(msg); | |
787 | return (0); | |
788 | } | |
1e08e787 | 789 | error("PAM: %s for %s%.100s from %.100s", msg, |
790 | sshpam_authctxt->valid ? "" : "illegal user ", | |
791 | sshpam_authctxt->user, | |
792 | get_remote_name_or_ip(utmp_len, options.use_dns)); | |
e250770b | 793 | /* FALLTHROUGH */ |
5daf7064 | 794 | default: |
05114c74 | 795 | *num = 0; |
796 | **echo_on = 0; | |
797 | xfree(msg); | |
798 | ctxt->pam_done = -1; | |
799 | return (-1); | |
800 | } | |
a5c9cd31 | 801 | } |
05114c74 | 802 | return (-1); |
a5c9cd31 | 803 | } |
804 | ||
05114c74 | 805 | /* XXX - see also comment in auth-chall.c:verify_response */ |
806 | static int | |
807 | sshpam_respond(void *ctx, u_int num, char **resp) | |
a5c9cd31 | 808 | { |
05114c74 | 809 | Buffer buffer; |
810 | struct pam_ctxt *ctxt = ctx; | |
811 | ||
912acf53 | 812 | debug2("PAM: %s entering, %u responses", __func__, num); |
05114c74 | 813 | switch (ctxt->pam_done) { |
814 | case 1: | |
815 | sshpam_authenticated = 1; | |
816 | return (0); | |
817 | case 0: | |
818 | break; | |
819 | default: | |
820 | return (-1); | |
a5c9cd31 | 821 | } |
05114c74 | 822 | if (num != 1) { |
823 | error("PAM: expected one response, got %u", num); | |
824 | return (-1); | |
825 | } | |
826 | buffer_init(&buffer); | |
2d5104e2 | 827 | if (sshpam_authctxt->valid && |
828 | (sshpam_authctxt->pw->pw_uid != 0 || | |
ed9e8be3 | 829 | options.permit_root_login == PERMIT_YES)) |
af0e5c2f | 830 | buffer_put_cstring(&buffer, *resp); |
831 | else | |
832 | buffer_put_cstring(&buffer, badpw); | |
7b2a0de3 | 833 | if (ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer) == -1) { |
834 | buffer_free(&buffer); | |
835 | return (-1); | |
836 | } | |
05114c74 | 837 | buffer_free(&buffer); |
838 | return (1); | |
a5c9cd31 | 839 | } |
840 | ||
05114c74 | 841 | static void |
842 | sshpam_free_ctx(void *ctxtp) | |
a5c9cd31 | 843 | { |
05114c74 | 844 | struct pam_ctxt *ctxt = ctxtp; |
39ce53de | 845 | |
90f3c272 | 846 | debug3("PAM: %s entering", __func__); |
c6630044 | 847 | sshpam_thread_cleanup(); |
05114c74 | 848 | xfree(ctxt); |
849 | /* | |
850 | * We don't call sshpam_cleanup() here because we may need the PAM | |
851 | * handle at a later stage, e.g. when setting up a session. It's | |
852 | * still on the cleanup list, so pam_end() *will* be called before | |
853 | * the server process terminates. | |
854 | */ | |
ad55cd03 | 855 | } |
856 | ||
05114c74 | 857 | KbdintDevice sshpam_device = { |
858 | "pam", | |
859 | sshpam_init_ctx, | |
860 | sshpam_query, | |
861 | sshpam_respond, | |
862 | sshpam_free_ctx | |
863 | }; | |
864 | ||
865 | KbdintDevice mm_sshpam_device = { | |
866 | "pam", | |
867 | mm_sshpam_init_ctx, | |
868 | mm_sshpam_query, | |
869 | mm_sshpam_respond, | |
870 | mm_sshpam_free_ctx | |
871 | }; | |
2919e060 | 872 | |
2b87da3b | 873 | /* |
05114c74 | 874 | * This replaces auth-pam.c |
ad55cd03 | 875 | */ |
05114c74 | 876 | void |
529d73ab | 877 | start_pam(Authctxt *authctxt) |
ad55cd03 | 878 | { |
817e6d38 | 879 | if (!options.use_pam) |
880 | fatal("PAM: initialisation requested when UsePAM=no"); | |
881 | ||
529d73ab | 882 | if (sshpam_init(authctxt) == -1) |
05114c74 | 883 | fatal("PAM: initialisation failed"); |
a5c9cd31 | 884 | } |
885 | ||
05114c74 | 886 | void |
887 | finish_pam(void) | |
a5c9cd31 | 888 | { |
c6630044 | 889 | sshpam_cleanup(); |
a5c9cd31 | 890 | } |
891 | ||
5b9e2464 | 892 | u_int |
893 | do_pam_account(void) | |
a5c9cd31 | 894 | { |
ba6dd90e | 895 | debug("%s: called", __func__); |
b3ef7fb7 | 896 | if (sshpam_account_status != -1) |
897 | return (sshpam_account_status); | |
898 | ||
5b9e2464 | 899 | sshpam_err = pam_acct_mgmt(sshpam_handle, 0); |
ba6dd90e | 900 | debug3("PAM: %s pam_acct_mgmt = %d (%s)", __func__, sshpam_err, |
901 | pam_strerror(sshpam_handle, sshpam_err)); | |
d1cf9a87 | 902 | |
b3ef7fb7 | 903 | if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD) { |
904 | sshpam_account_status = 0; | |
905 | return (sshpam_account_status); | |
5b9e2464 | 906 | } |
907 | ||
b3ef7fb7 | 908 | if (sshpam_err == PAM_NEW_AUTHTOK_REQD) |
c10bb2ce | 909 | sshpam_password_change_required(1); |
b3ef7fb7 | 910 | |
911 | sshpam_account_status = 1; | |
912 | return (sshpam_account_status); | |
05114c74 | 913 | } |
46c76c63 | 914 | |
49e82bb9 | 915 | void |
916 | do_pam_set_tty(const char *tty) | |
917 | { | |
26b3608b | 918 | if (tty != NULL) { |
919 | debug("PAM: setting PAM_TTY to \"%s\"", tty); | |
920 | sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty); | |
921 | if (sshpam_err != PAM_SUCCESS) | |
922 | fatal("PAM: failed to set PAM_TTY: %s", | |
923 | pam_strerror(sshpam_handle, sshpam_err)); | |
924 | } | |
05114c74 | 925 | } |
cbd7492e | 926 | |
05114c74 | 927 | void |
928 | do_pam_setcred(int init) | |
929 | { | |
930 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, | |
ba6dd90e | 931 | (const void *)&store_conv); |
05114c74 | 932 | if (sshpam_err != PAM_SUCCESS) |
933 | fatal("PAM: failed to set PAM_CONV: %s", | |
934 | pam_strerror(sshpam_handle, sshpam_err)); | |
935 | if (init) { | |
936 | debug("PAM: establishing credentials"); | |
937 | sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED); | |
938 | } else { | |
939 | debug("PAM: reinitializing credentials"); | |
940 | sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED); | |
941 | } | |
942 | if (sshpam_err == PAM_SUCCESS) { | |
943 | sshpam_cred_established = 1; | |
944 | return; | |
945 | } | |
946 | if (sshpam_authenticated) | |
947 | fatal("PAM: pam_setcred(): %s", | |
948 | pam_strerror(sshpam_handle, sshpam_err)); | |
949 | else | |
950 | debug("PAM: pam_setcred(): %s", | |
951 | pam_strerror(sshpam_handle, sshpam_err)); | |
a5c9cd31 | 952 | } |
953 | ||
05114c74 | 954 | static int |
44171182 | 955 | sshpam_tty_conv(int n, sshpam_const struct pam_message **msg, |
5b9e2464 | 956 | struct pam_response **resp, void *data) |
ee48c949 | 957 | { |
05114c74 | 958 | char input[PAM_MAX_MSG_SIZE]; |
0a23d79f | 959 | struct pam_response *reply; |
ee48c949 | 960 | int i; |
961 | ||
60922169 | 962 | debug3("PAM: %s called with %d messages", __func__, n); |
963 | ||
0a23d79f | 964 | *resp = NULL; |
965 | ||
3eaf3960 | 966 | if (n <= 0 || n > PAM_MAX_NUM_MSG || !isatty(STDIN_FILENO)) |
05114c74 | 967 | return (PAM_CONV_ERR); |
0a23d79f | 968 | |
01d35895 | 969 | if ((reply = calloc(n, sizeof(*reply))) == NULL) |
0a23d79f | 970 | return (PAM_CONV_ERR); |
0a23d79f | 971 | |
05114c74 | 972 | for (i = 0; i < n; ++i) { |
973 | switch (PAM_MSG_MEMBER(msg, i, msg_style)) { | |
974 | case PAM_PROMPT_ECHO_OFF: | |
0a23d79f | 975 | reply[i].resp = |
aff51935 | 976 | read_passphrase(PAM_MSG_MEMBER(msg, i, msg), |
05114c74 | 977 | RP_ALLOW_STDIN); |
0a23d79f | 978 | reply[i].resp_retcode = PAM_SUCCESS; |
05114c74 | 979 | break; |
980 | case PAM_PROMPT_ECHO_ON: | |
74117b26 | 981 | fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg)); |
05114c74 | 982 | fgets(input, sizeof input, stdin); |
8936b151 | 983 | if ((reply[i].resp = strdup(input)) == NULL) |
984 | goto fail; | |
0a23d79f | 985 | reply[i].resp_retcode = PAM_SUCCESS; |
05114c74 | 986 | break; |
987 | case PAM_ERROR_MSG: | |
988 | case PAM_TEXT_INFO: | |
74117b26 | 989 | fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg)); |
0a23d79f | 990 | reply[i].resp_retcode = PAM_SUCCESS; |
05114c74 | 991 | break; |
992 | default: | |
993 | goto fail; | |
994 | } | |
ee48c949 | 995 | } |
0a23d79f | 996 | *resp = reply; |
05114c74 | 997 | return (PAM_SUCCESS); |
0a23d79f | 998 | |
05114c74 | 999 | fail: |
0a23d79f | 1000 | for(i = 0; i < n; i++) { |
1001 | if (reply[i].resp != NULL) | |
1002 | xfree(reply[i].resp); | |
1003 | } | |
1004 | xfree(reply); | |
05114c74 | 1005 | return (PAM_CONV_ERR); |
ee48c949 | 1006 | } |
1007 | ||
8600a4ab | 1008 | static struct pam_conv tty_conv = { sshpam_tty_conv, NULL }; |
3eaf3960 | 1009 | |
05114c74 | 1010 | /* |
1011 | * XXX this should be done in the authentication phase, but ssh1 doesn't | |
1012 | * support that | |
1013 | */ | |
1014 | void | |
1015 | do_pam_chauthtok(void) | |
a5c9cd31 | 1016 | { |
05114c74 | 1017 | if (use_privsep) |
5b9e2464 | 1018 | fatal("Password expired (unable to change with privsep)"); |
05114c74 | 1019 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, |
3eaf3960 | 1020 | (const void *)&tty_conv); |
05114c74 | 1021 | if (sshpam_err != PAM_SUCCESS) |
1022 | fatal("PAM: failed to set PAM_CONV: %s", | |
1023 | pam_strerror(sshpam_handle, sshpam_err)); | |
1024 | debug("PAM: changing password"); | |
1025 | sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK); | |
1026 | if (sshpam_err != PAM_SUCCESS) | |
1027 | fatal("PAM: pam_chauthtok(): %s", | |
1028 | pam_strerror(sshpam_handle, sshpam_err)); | |
5daf7064 | 1029 | } |
1030 | ||
3eaf3960 | 1031 | void |
1032 | do_pam_session(void) | |
1033 | { | |
dd1fb864 | 1034 | debug3("PAM: opening session"); |
aff51935 | 1035 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, |
ef687c66 | 1036 | (const void *)&store_conv); |
3eaf3960 | 1037 | if (sshpam_err != PAM_SUCCESS) |
1038 | fatal("PAM: failed to set PAM_CONV: %s", | |
1039 | pam_strerror(sshpam_handle, sshpam_err)); | |
1040 | sshpam_err = pam_open_session(sshpam_handle, 0); | |
abdec250 | 1041 | if (sshpam_err == PAM_SUCCESS) |
1042 | sshpam_session_open = 1; | |
1043 | else { | |
1044 | sshpam_session_open = 0; | |
1045 | disable_forwarding(); | |
1046 | error("PAM: pam_open_session(): %s", | |
3eaf3960 | 1047 | pam_strerror(sshpam_handle, sshpam_err)); |
abdec250 | 1048 | } |
1049 | ||
1050 | } | |
1051 | ||
1052 | int | |
1053 | is_pam_session_open(void) | |
1054 | { | |
1055 | return sshpam_session_open; | |
3eaf3960 | 1056 | } |
1057 | ||
aff51935 | 1058 | /* |
749560dd | 1059 | * Set a PAM environment string. We need to do this so that the session |
1060 | * modules can handle things like Kerberos/GSI credentials that appear | |
1061 | * during the ssh authentication process. | |
1062 | */ | |
749560dd | 1063 | int |
aff51935 | 1064 | do_pam_putenv(char *name, char *value) |
749560dd | 1065 | { |
749560dd | 1066 | int ret = 1; |
b6453d99 | 1067 | #ifdef HAVE_PAM_PUTENV |
263c65df | 1068 | char *compound; |
1069 | size_t len; | |
1070 | ||
1071 | len = strlen(name) + strlen(value) + 2; | |
1072 | compound = xmalloc(len); | |
1073 | ||
1074 | snprintf(compound, len, "%s=%s", name, value); | |
1075 | ret = pam_putenv(sshpam_handle, compound); | |
1076 | xfree(compound); | |
749560dd | 1077 | #endif |
263c65df | 1078 | |
749560dd | 1079 | return (ret); |
1080 | } | |
1081 | ||
2212fc98 | 1082 | char ** |
1083 | fetch_pam_child_environment(void) | |
1084 | { | |
1085 | return sshpam_env; | |
1086 | } | |
1087 | ||
05114c74 | 1088 | char ** |
1089 | fetch_pam_environment(void) | |
1090 | { | |
05114c74 | 1091 | return (pam_getenvlist(sshpam_handle)); |
05114c74 | 1092 | } |
5c377b3b | 1093 | |
05114c74 | 1094 | void |
1095 | free_pam_environment(char **env) | |
1096 | { | |
1097 | char **envp; | |
5daf7064 | 1098 | |
0eb6370a | 1099 | if (env == NULL) |
1100 | return; | |
1101 | ||
05114c74 | 1102 | for (envp = env; *envp; envp++) |
1103 | xfree(*envp); | |
1104 | xfree(env); | |
a5c9cd31 | 1105 | } |
1106 | ||
5de92f17 | 1107 | /* |
1108 | * "Blind" conversation function for password authentication. Assumes that | |
1109 | * echo-off prompts are for the password and stores messages for later | |
1110 | * display. | |
1111 | */ | |
1112 | static int | |
44171182 | 1113 | sshpam_passwd_conv(int n, sshpam_const struct pam_message **msg, |
5de92f17 | 1114 | struct pam_response **resp, void *data) |
1115 | { | |
1116 | struct pam_response *reply; | |
1117 | int i; | |
1118 | size_t len; | |
1119 | ||
1120 | debug3("PAM: %s called with %d messages", __func__, n); | |
1121 | ||
1122 | *resp = NULL; | |
1123 | ||
1124 | if (n <= 0 || n > PAM_MAX_NUM_MSG) | |
1125 | return (PAM_CONV_ERR); | |
1126 | ||
1127 | if ((reply = malloc(n * sizeof(*reply))) == NULL) | |
1128 | return (PAM_CONV_ERR); | |
1129 | memset(reply, 0, n * sizeof(*reply)); | |
1130 | ||
1131 | for (i = 0; i < n; ++i) { | |
1132 | switch (PAM_MSG_MEMBER(msg, i, msg_style)) { | |
1133 | case PAM_PROMPT_ECHO_OFF: | |
1134 | if (sshpam_password == NULL) | |
1135 | goto fail; | |
8936b151 | 1136 | if ((reply[i].resp = strdup(sshpam_password)) == NULL) |
1137 | goto fail; | |
5de92f17 | 1138 | reply[i].resp_retcode = PAM_SUCCESS; |
1139 | break; | |
1140 | case PAM_ERROR_MSG: | |
1141 | case PAM_TEXT_INFO: | |
1142 | len = strlen(PAM_MSG_MEMBER(msg, i, msg)); | |
1143 | if (len > 0) { | |
1144 | buffer_append(&loginmsg, | |
1145 | PAM_MSG_MEMBER(msg, i, msg), len); | |
1146 | buffer_append(&loginmsg, "\n", 1); | |
1147 | } | |
8936b151 | 1148 | if ((reply[i].resp = strdup("")) == NULL) |
1149 | goto fail; | |
5de92f17 | 1150 | reply[i].resp_retcode = PAM_SUCCESS; |
1151 | break; | |
1152 | default: | |
1153 | goto fail; | |
1154 | } | |
1155 | } | |
1156 | *resp = reply; | |
1157 | return (PAM_SUCCESS); | |
1158 | ||
d1cf9a87 | 1159 | fail: |
5de92f17 | 1160 | for(i = 0; i < n; i++) { |
1161 | if (reply[i].resp != NULL) | |
1162 | xfree(reply[i].resp); | |
1163 | } | |
1164 | xfree(reply); | |
1165 | return (PAM_CONV_ERR); | |
1166 | } | |
1167 | ||
1168 | static struct pam_conv passwd_conv = { sshpam_passwd_conv, NULL }; | |
1169 | ||
1170 | /* | |
1171 | * Attempt password authentication via PAM | |
1172 | */ | |
1173 | int | |
1174 | sshpam_auth_passwd(Authctxt *authctxt, const char *password) | |
1175 | { | |
1176 | int flags = (options.permit_empty_passwd == 0 ? | |
1177 | PAM_DISALLOW_NULL_AUTHTOK : 0); | |
1178 | ||
1179 | if (!options.use_pam || sshpam_handle == NULL) | |
1180 | fatal("PAM: %s called when PAM disabled or failed to " | |
1181 | "initialise.", __func__); | |
1182 | ||
1183 | sshpam_password = password; | |
1184 | sshpam_authctxt = authctxt; | |
1185 | ||
0e716148 | 1186 | /* |
1187 | * If the user logging in is invalid, or is root but is not permitted | |
1188 | * by PermitRootLogin, use an invalid password to prevent leaking | |
1189 | * information via timing (eg if the PAM config has a delay on fail). | |
1190 | */ | |
2d5104e2 | 1191 | if (!authctxt->valid || (authctxt->pw->pw_uid == 0 && |
ed9e8be3 | 1192 | options.permit_root_login != PERMIT_YES)) |
0e716148 | 1193 | sshpam_password = badpw; |
1194 | ||
5de92f17 | 1195 | sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, |
1196 | (const void *)&passwd_conv); | |
1197 | if (sshpam_err != PAM_SUCCESS) | |
1198 | fatal("PAM: %s: failed to set PAM_CONV: %s", __func__, | |
1199 | pam_strerror(sshpam_handle, sshpam_err)); | |
1200 | ||
1201 | sshpam_err = pam_authenticate(sshpam_handle, flags); | |
1202 | sshpam_password = NULL; | |
2d5104e2 | 1203 | if (sshpam_err == PAM_SUCCESS && authctxt->valid) { |
5de92f17 | 1204 | debug("PAM: password authentication accepted for %.100s", |
1205 | authctxt->user); | |
ed9e8be3 | 1206 | return 1; |
5de92f17 | 1207 | } else { |
1208 | debug("PAM: password authentication failed for %.100s: %s", | |
1209 | authctxt->valid ? authctxt->user : "an illegal user", | |
1210 | pam_strerror(sshpam_handle, sshpam_err)); | |
1211 | return 0; | |
1212 | } | |
1213 | } | |
a5c9cd31 | 1214 | #endif /* USE_PAM */ |