Instead of duplicating the Kerberos tools, use a single version.
[dragonfly.git] / secure / usr.sbin / sshd / auth2-pam-freebsd.c
CommitLineData
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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.
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.
18 *
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.
30 *
31 * $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.1.2.6 2003/04/07 09:56:46 des Exp $
58ee8f13 32 * $DragonFly: src/secure/usr.sbin/sshd/Attic/auth2-pam-freebsd.c,v 1.3 2005/07/11 22:49:46 corecode Exp $
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33 */
34
35#include "includes.h"
36
37#ifdef USE_PAM
38#include <security/pam_appl.h>
39
40#include "auth.h"
41#include "auth-pam.h"
42#include "buffer.h"
43#include "bufaux.h"
44#include "canohost.h"
45#include "log.h"
46#include "monitor_wrap.h"
47#include "msg.h"
48#include "packet.h"
7258d1e7 49#include "misc.h"
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50#include "servconf.h"
51#include "ssh2.h"
52#include "xmalloc.h"
53
54#ifdef USE_POSIX_THREADS
55#include <pthread.h>
56#else
57typedef pid_t pthread_t;
58#endif
59
60struct pam_ctxt {
61 pthread_t pam_thread;
62 int pam_psock;
63 int pam_csock;
64 int pam_done;
65};
66
67static void sshpam_free_ctx(void *);
68static struct pam_ctxt *cleanup_ctxt;
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69static Authctxt *sshpam_authctxt = NULL;
70static const char *sshpam_password = NULL;
71
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72
73#ifndef USE_POSIX_THREADS
74/*
75 * Simulate threads with processes.
76 */
77
78static int sshpam_thread_status = -1;
79static mysig_t sshpam_oldsig;
80
81static void
82sshpam_sigchld_handler(int sig)
83{
84 if (cleanup_ctxt == NULL)
85 return; /* handler called after PAM cleanup, shouldn't happen */
86 if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0) == -1)
87 return; /* couldn't wait for process */
88 if (WIFSIGNALED(sshpam_thread_status) &&
89 WTERMSIG(sshpam_thread_status) == SIGTERM)
90 return; /* terminated by pthread_cancel */
91 if (!WIFEXITED(sshpam_thread_status))
92 fatal("PAM: authentication thread exited unexpectedly");
93 if (WEXITSTATUS(sshpam_thread_status) != 0)
94 fatal("PAM: authentication thread exited uncleanly");
95}
96
97
98static void
99pthread_exit(void *value __unused)
100{
101 _exit(0);
102}
103
104static int
105pthread_create(pthread_t *thread, const void *attr __unused,
106 void *(*thread_start)(void *), void *arg)
107{
108 pid_t pid;
109
110 switch ((pid = fork())) {
111 case -1:
112 error("fork(): %s", strerror(errno));
113 return (-1);
114 case 0:
115 thread_start(arg);
116 _exit(1);
117 default:
118 *thread = pid;
119 sshpam_oldsig = signal(SIGCHLD, sshpam_sigchld_handler);
120 return (0);
121 }
122}
123
124static int
125pthread_cancel(pthread_t thread)
126{
127 signal(SIGCHLD, sshpam_oldsig);
128 return (kill(thread, SIGTERM));
129}
130
131static int
132pthread_join(pthread_t thread, void **value __unused)
133{
134 int status;
135
136 if (sshpam_thread_status != -1)
137 return (sshpam_thread_status);
138 signal(SIGCHLD, sshpam_oldsig);
139 waitpid(thread, &status, 0);
140 return (status);
141}
142#endif
143
144
145extern ServerOptions options;
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146extern Buffer loginmsg;
147extern int compat20;
148extern u_int utmp_len;
149
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150static pam_handle_t *sshpam_handle;
151static int sshpam_err;
152static int sshpam_authenticated;
153static int sshpam_new_authtok_reqd;
154static int sshpam_session_open;
155static int sshpam_cred_established;
156
157/*
158 * Conversation function for authentication thread.
159 */
160static int
161sshpam_thread_conv(int n,
162 const struct pam_message **msg,
163 struct pam_response **resp,
164 void *data)
165{
166 Buffer buffer;
167 struct pam_ctxt *ctxt;
168 int i;
169
170 ctxt = data;
171 if (n <= 0 || n > PAM_MAX_NUM_MSG)
172 return (PAM_CONV_ERR);
173 *resp = xmalloc(n * sizeof **resp);
174 buffer_init(&buffer);
175 for (i = 0; i < n; ++i) {
176 resp[i]->resp_retcode = 0;
177 resp[i]->resp = NULL;
178 switch (msg[i]->msg_style) {
179 case PAM_PROMPT_ECHO_OFF:
180 buffer_put_cstring(&buffer, msg[i]->msg);
181 ssh_msg_send(ctxt->pam_csock, msg[i]->msg_style, &buffer);
182 ssh_msg_recv(ctxt->pam_csock, &buffer);
183 if (buffer_get_char(&buffer) != PAM_AUTHTOK)
184 goto fail;
185 resp[i]->resp = buffer_get_string(&buffer, NULL);
186 break;
187 case PAM_PROMPT_ECHO_ON:
188 buffer_put_cstring(&buffer, msg[i]->msg);
189 ssh_msg_send(ctxt->pam_csock, msg[i]->msg_style, &buffer);
190 ssh_msg_recv(ctxt->pam_csock, &buffer);
191 if (buffer_get_char(&buffer) != PAM_AUTHTOK)
192 goto fail;
193 resp[i]->resp = buffer_get_string(&buffer, NULL);
194 break;
195 case PAM_ERROR_MSG:
196 buffer_put_cstring(&buffer, msg[i]->msg);
197 ssh_msg_send(ctxt->pam_csock, msg[i]->msg_style, &buffer);
198 break;
199 case PAM_TEXT_INFO:
200 buffer_put_cstring(&buffer, msg[i]->msg);
201 ssh_msg_send(ctxt->pam_csock, msg[i]->msg_style, &buffer);
202 break;
203 default:
204 goto fail;
205 }
206 buffer_clear(&buffer);
207 }
208 buffer_free(&buffer);
209 return (PAM_SUCCESS);
210 fail:
211 while (i)
212 xfree(resp[--i]);
213 xfree(*resp);
214 *resp = NULL;
215 buffer_free(&buffer);
216 return (PAM_CONV_ERR);
217}
218
219/*
220 * Authentication thread.
221 */
222static void *
223sshpam_thread(void *ctxtp)
224{
225 struct pam_ctxt *ctxt = ctxtp;
226 Buffer buffer;
227 struct pam_conv pam_conv = { sshpam_thread_conv, ctxt };
228
229#ifndef USE_POSIX_THREADS
230 {
231 const char *pam_user;
232
233 pam_get_item(sshpam_handle, PAM_USER, (const void **)&pam_user);
234 setproctitle("%s [pam]", pam_user);
235 }
236#endif
237 buffer_init(&buffer);
238 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, (const void *)&pam_conv);
239 if (sshpam_err != PAM_SUCCESS)
240 goto auth_fail;
241 sshpam_err = pam_authenticate(sshpam_handle, 0);
242 if (sshpam_err != PAM_SUCCESS)
243 goto auth_fail;
244 sshpam_err = pam_acct_mgmt(sshpam_handle, 0);
245 if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD)
246 goto auth_fail;
247 buffer_put_cstring(&buffer, "OK");
248 ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer);
249 buffer_free(&buffer);
250 pthread_exit(NULL);
251 auth_fail:
252 buffer_put_cstring(&buffer,
253 pam_strerror(sshpam_handle, sshpam_err));
254 ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer);
255 buffer_free(&buffer);
256 pthread_exit(NULL);
257}
258
259void
260sshpam_thread_cleanup(void)
261{
262 struct pam_ctxt *ctxt = cleanup_ctxt;
263
264 if (ctxt != NULL && ctxt->pam_thread != 0) {
265 pthread_cancel(ctxt->pam_thread);
266 pthread_join(ctxt->pam_thread, NULL);
267 close(ctxt->pam_psock);
268 close(ctxt->pam_csock);
269 memset(ctxt, 0, sizeof(*ctxt));
270 cleanup_ctxt = NULL;
271 }
272}
273
274static int
275sshpam_null_conv(int n,
276 const struct pam_message **msg,
277 struct pam_response **resp,
278 void *data)
279{
280
281 return (PAM_CONV_ERR);
282}
283
284static struct pam_conv null_conv = { sshpam_null_conv, NULL };
285
286void
287sshpam_cleanup(void)
288{
289 debug("PAM: cleanup");
290 pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
291 if (sshpam_cred_established) {
292 pam_setcred(sshpam_handle, PAM_DELETE_CRED);
293 sshpam_cred_established = 0;
294 }
295 if (sshpam_session_open) {
296 pam_close_session(sshpam_handle, PAM_SILENT);
297 sshpam_session_open = 0;
298 }
299 sshpam_authenticated = sshpam_new_authtok_reqd = 0;
300 pam_end(sshpam_handle, sshpam_err);
301 sshpam_handle = NULL;
302}
303
304static int
305sshpam_init(Authctxt *authctxt)
306{
307 extern u_int utmp_len;
308 const char *pam_rhost, *pam_user, *user = authctxt->user;
309
310 if (sshpam_handle != NULL) {
311 /* We already have a PAM context; check if the user matches */
312 sshpam_err = pam_get_item(sshpam_handle,
313 PAM_USER, (const void **)&pam_user);
314 if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0)
315 return (0);
316 pam_end(sshpam_handle, sshpam_err);
317 sshpam_handle = NULL;
318 }
319 debug("PAM: initializing for \"%s\"", user);
320 sshpam_err = pam_start("sshd", user, &null_conv, &sshpam_handle);
321 if (sshpam_err != PAM_SUCCESS)
322 return (-1);
323 pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns);
324 debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost);
325 sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost);
326 if (sshpam_err != PAM_SUCCESS) {
327 pam_end(sshpam_handle, sshpam_err);
328 sshpam_handle = NULL;
329 return (-1);
330 }
331 return (0);
332}
333
334static void *
335sshpam_init_ctx(Authctxt *authctxt)
336{
337 struct pam_ctxt *ctxt;
338 int socks[2];
339
340 /* Initialize PAM */
341 if (sshpam_init(authctxt) == -1) {
342 error("PAM: initialization failed");
343 return (NULL);
344 }
345
346 ctxt = xmalloc(sizeof *ctxt);
347 ctxt->pam_done = 0;
348
349 /* Start the authentication thread */
350 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) {
351 error("PAM: failed create sockets: %s", strerror(errno));
352 xfree(ctxt);
353 return (NULL);
354 }
355 ctxt->pam_psock = socks[0];
356 ctxt->pam_csock = socks[1];
357 if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) {
358 error("PAM: failed to start authentication thread: %s",
359 strerror(errno));
360 close(socks[0]);
361 close(socks[1]);
362 xfree(ctxt);
363 return (NULL);
364 }
365 cleanup_ctxt = ctxt;
366 return (ctxt);
367}
368
369static int
370sshpam_query(void *ctx, char **name, char **info,
371 u_int *num, char ***prompts, u_int **echo_on)
372{
373 Buffer buffer;
374 struct pam_ctxt *ctxt = ctx;
375 size_t plen;
376 u_char type;
377 char *msg;
378
379 buffer_init(&buffer);
380 *name = xstrdup("");
381 *info = xstrdup("");
382 *prompts = xmalloc(sizeof(char *));
383 **prompts = NULL;
384 plen = 0;
385 *echo_on = xmalloc(sizeof(u_int));
386 while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) {
387 type = buffer_get_char(&buffer);
388 msg = buffer_get_string(&buffer, NULL);
389 switch (type) {
390 case PAM_PROMPT_ECHO_ON:
391 case PAM_PROMPT_ECHO_OFF:
392 *num = 1;
393 **prompts = xrealloc(**prompts, plen + strlen(msg) + 1);
394 plen += sprintf(**prompts + plen, "%s", msg);
395 **echo_on = (type == PAM_PROMPT_ECHO_ON);
396 xfree(msg);
397 return (0);
398 case PAM_ERROR_MSG:
399 case PAM_TEXT_INFO:
400 /* accumulate messages */
401 **prompts = xrealloc(**prompts, plen + strlen(msg) + 1);
402 plen += sprintf(**prompts + plen, "%s", msg);
403 xfree(msg);
404 break;
405 case PAM_NEW_AUTHTOK_REQD:
406 sshpam_new_authtok_reqd = 1;
407 /* FALLTHROUGH */
408 case PAM_SUCCESS:
409 case PAM_AUTH_ERR:
410 if (**prompts != NULL) {
411 /* drain any accumulated messages */
412#if 0 /* not compatible with privsep */
413 packet_start(SSH2_MSG_USERAUTH_BANNER);
414 packet_put_cstring(**prompts);
415 packet_put_cstring("");
416 packet_send();
417 packet_write_wait();
418#endif
419 xfree(**prompts);
420 **prompts = NULL;
421 }
422 if (type == PAM_SUCCESS) {
423 *num = 0;
424 **echo_on = 0;
425 ctxt->pam_done = 1;
426 xfree(msg);
427 return (0);
428 }
429 error("PAM: %s", msg);
430 default:
431 *num = 0;
432 **echo_on = 0;
433 xfree(msg);
434 ctxt->pam_done = -1;
435 return (-1);
436 }
437 }
438 return (-1);
439}
440
441static int
442sshpam_respond(void *ctx, u_int num, char **resp)
443{
444 Buffer buffer;
445 struct pam_ctxt *ctxt = ctx;
446 char *msg;
447
448 debug2("PAM: %s", __func__);
449 switch (ctxt->pam_done) {
450 case 1:
451 sshpam_authenticated = 1;
452 return (0);
453 case 0:
454 break;
455 default:
456 return (-1);
457 }
458 if (num != 1) {
459 error("PAM: expected one response, got %u", num);
460 return (-1);
461 }
462 buffer_init(&buffer);
463 buffer_put_cstring(&buffer, *resp);
464 ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer);
465 buffer_free(&buffer);
466 return (1);
467}
468
469static void
470sshpam_free_ctx(void *ctxtp)
471{
472 struct pam_ctxt *ctxt = ctxtp;
473
474 sshpam_thread_cleanup();
475 xfree(ctxt);
476 /*
477 * We don't call pam_cleanup() here because we may need the PAM
478 * handle at a later stage, e.g. when setting up a session. It's
479 * still on the cleanup list, so pam_end() *will* be called before
480 * the server process terminates.
481 */
482}
483
484KbdintDevice sshpam_device = {
485 "pam",
486 sshpam_init_ctx,
487 sshpam_query,
488 sshpam_respond,
489 sshpam_free_ctx
490};
491
492KbdintDevice mm_sshpam_device = {
493 "pam",
494 mm_sshpam_init_ctx,
495 mm_sshpam_query,
496 mm_sshpam_respond,
497 mm_sshpam_free_ctx
498};
499
500/*
501 * This replaces auth-pam.c
502 */
503void
504start_pam(Authctxt *authctxt)
505{
506 if (!options.use_pam)
507 fatal("PAM: initialisation requested when UsePAM=no");
508
509 if (sshpam_init(authctxt) == -1)
510 fatal("PAM: initialisation failed");
511}
512
513void
514finish_pam(void)
515{
516 sshpam_cleanup();
517}
518
519u_int
520do_pam_account(void)
521{
522 /* XXX */
523 return (1);
524}
525
526void
527do_pam_set_tty(const char *tty)
528{
529 if (tty != NULL) {
530 debug("PAM: setting PAM_TTY to \"%s\"", tty);
531 sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty);
532 if (sshpam_err != PAM_SUCCESS)
533 fatal("PAM: failed to set PAM_TTY: %s",
534 pam_strerror(sshpam_handle, sshpam_err));
535 }
536}
537
538void
539do_pam_session(void)
540{
541 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
542 if (sshpam_err != PAM_SUCCESS)
543 fatal("PAM: failed to set PAM_CONV: %s",
544 pam_strerror(sshpam_handle, sshpam_err));
545 sshpam_err = pam_open_session(sshpam_handle, 0);
546 if (sshpam_err != PAM_SUCCESS)
547 fatal("PAM: pam_open_session(): %s",
548 pam_strerror(sshpam_handle, sshpam_err));
549 sshpam_session_open = 1;
550}
551
58ee8f13
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552int
553is_pam_session_open(void)
554{
555 return sshpam_session_open;
556}
557
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558void
559do_pam_setcred(int init)
560{
561 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
562 if (sshpam_err != PAM_SUCCESS)
563 fatal("PAM: failed to set PAM_CONV: %s",
564 pam_strerror(sshpam_handle, sshpam_err));
565 if (init) {
566 debug("PAM: establishing credentials");
567 sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED);
568 } else {
569 debug("PAM: reinitializing credentials");
570 sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED);
571 }
572 if (sshpam_err == PAM_SUCCESS) {
573 sshpam_cred_established = 1;
574 return;
575 }
576 if (sshpam_authenticated)
577 fatal("PAM: pam_setcred(): %s",
578 pam_strerror(sshpam_handle, sshpam_err));
579 else
580 debug("PAM: pam_setcred(): %s",
581 pam_strerror(sshpam_handle, sshpam_err));
582}
583
584int
585is_pam_password_change_required(void)
586{
587 return (sshpam_new_authtok_reqd);
588}
589
590static int
591sshpam_chauthtok_conv(int n,
592 const struct pam_message **msg,
593 struct pam_response **resp,
594 void *data)
595{
596 char input[PAM_MAX_MSG_SIZE];
597 int i;
598
599 if (n <= 0 || n > PAM_MAX_NUM_MSG)
600 return (PAM_CONV_ERR);
601 *resp = xmalloc(n * sizeof **resp);
602 for (i = 0; i < n; ++i) {
603 switch (msg[i]->msg_style) {
604 case PAM_PROMPT_ECHO_OFF:
605 resp[i]->resp =
606 read_passphrase(msg[i]->msg, RP_ALLOW_STDIN);
607 resp[i]->resp_retcode = PAM_SUCCESS;
608 break;
609 case PAM_PROMPT_ECHO_ON:
610 fputs(msg[i]->msg, stderr);
611 fgets(input, sizeof input, stdin);
612 resp[i]->resp = xstrdup(input);
613 resp[i]->resp_retcode = PAM_SUCCESS;
614 break;
615 case PAM_ERROR_MSG:
616 case PAM_TEXT_INFO:
617 fputs(msg[i]->msg, stderr);
618 resp[i]->resp_retcode = PAM_SUCCESS;
619 break;
620 default:
621 goto fail;
622 }
623 }
624 return (PAM_SUCCESS);
625 fail:
626 while (i)
627 xfree(resp[--i]);
628 xfree(*resp);
629 *resp = NULL;
630 return (PAM_CONV_ERR);
631}
632
633/*
634 * XXX this should be done in the authentication phase, but ssh1 doesn't
635 * support that
636 */
637void
638do_pam_chauthtok(void)
639{
640 struct pam_conv pam_conv = { sshpam_chauthtok_conv, NULL };
641
642 if (use_privsep)
643 fatal("PAM: chauthtok not supprted with privsep");
644 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, (const void *)&pam_conv);
645 if (sshpam_err != PAM_SUCCESS)
646 fatal("PAM: failed to set PAM_CONV: %s",
647 pam_strerror(sshpam_handle, sshpam_err));
648 debug("PAM: changing password");
649 sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK);
650 if (sshpam_err != PAM_SUCCESS)
651 fatal("PAM: pam_chauthtok(): %s",
652 pam_strerror(sshpam_handle, sshpam_err));
653}
654
655void
656print_pam_messages(void)
657{
658 /* XXX */
659}
660
661char **
662fetch_pam_child_environment(void)
663{
664 /* XXX */
665 return (NULL);
666}
667
668char **
669fetch_pam_environment(void)
670{
671#ifdef HAVE_PAM_GETENVLIST
672 debug("PAM: retrieving environment");
673 return (pam_getenvlist(sshpam_handle));
674#else
675 return (NULL);
676#endif
677}
678
679void
680free_pam_environment(char **env)
681{
682 char **envp;
683
684 if (env == NULL)
685 return;
686
687 for (envp = env; *envp; envp++)
688 xfree(*envp);
689 xfree(env);
690}
691
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692/*
693 * "Blind" conversation function for password authentication. Assumes that
694 * echo-off prompts are for the password and stores messages for later
695 * display.
696 */
697static int
58ee8f13 698sshpam_passwd_conv(int n, const struct pam_message **msg,
7258d1e7
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699 struct pam_response **resp, void *data)
700{
701 struct pam_response *reply;
702 int i;
703 size_t len;
704
705 debug3("PAM: %s called with %d messages", __func__, n);
706
707 *resp = NULL;
708
709 if (n <= 0 || n > PAM_MAX_NUM_MSG)
710 return (PAM_CONV_ERR);
711
712 if ((reply = malloc(n * sizeof(*reply))) == NULL)
713 return (PAM_CONV_ERR);
714 memset(reply, 0, n * sizeof(*reply));
715
716 for (i = 0; i < n; ++i) {
717 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
718 case PAM_PROMPT_ECHO_OFF:
719 if (sshpam_password == NULL)
720 goto fail;
721 if ((reply[i].resp = strdup(sshpam_password)) == NULL)
722 goto fail;
723 reply[i].resp_retcode = PAM_SUCCESS;
724 break;
725 case PAM_ERROR_MSG:
726 case PAM_TEXT_INFO:
727 len = strlen(PAM_MSG_MEMBER(msg, i, msg));
728 if (len > 0) {
729 buffer_append(&loginmsg,
730 PAM_MSG_MEMBER(msg, i, msg), len);
731 buffer_append(&loginmsg, "\n", 1);
732 }
733 if ((reply[i].resp = strdup("")) == NULL)
734 goto fail;
735 reply[i].resp_retcode = PAM_SUCCESS;
736 break;
737 default:
738 goto fail;
739 }
740 }
741 *resp = reply;
742 return (PAM_SUCCESS);
743
744 fail:
745 for(i = 0; i < n; i++) {
746 if (reply[i].resp != NULL)
747 xfree(reply[i].resp);
748 }
749 xfree(reply);
750 return (PAM_CONV_ERR);
751}
752
753static struct pam_conv passwd_conv = { sshpam_passwd_conv, NULL };
754
755sshpam_auth_passwd(Authctxt *authctxt, const char *password)
756{
757 int flags = (options.permit_empty_passwd == 0 ?
758 PAM_DISALLOW_NULL_AUTHTOK : 0);
759 static char badpw[] = "\b\n\r\177INCORRECT";
760
761 if (!options.use_pam || sshpam_handle == NULL)
762 fatal("PAM: %s called when PAM disabled or failed to "
763 "initialise.", __func__);
764
765 sshpam_password = password;
766 sshpam_authctxt = authctxt;
767
768 /*
769 * If the user logging in is invalid, or is root but is not permitted
770 * by PermitRootLogin, use an invalid password to prevent leaking
771 * information via timing (eg if the PAM config has a delay on fail).
772 */
773 if (!authctxt->valid || (authctxt->pw->pw_uid == 0 &&
774 options.permit_root_login != PERMIT_YES))
775 sshpam_password = badpw;
776
777 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
778 (const void *)&passwd_conv);
779 if (sshpam_err != PAM_SUCCESS)
780 fatal("PAM: %s: failed to set PAM_CONV: %s", __func__,
781 pam_strerror(sshpam_handle, sshpam_err));
782
783 sshpam_err = pam_authenticate(sshpam_handle, flags);
784 sshpam_password = NULL;
785 if (sshpam_err == PAM_SUCCESS && authctxt->valid) {
786 debug("PAM: password authentication accepted for %.100s",
787 authctxt->user);
788 return 1;
789 } else {
790 debug("PAM: password authentication failed for %.100s: %s",
791 authctxt->valid ? authctxt->user : "an illegal user",
792 pam_strerror(sshpam_handle, sshpam_err));
793 return 0;
794 }
795}
796
16feab21 797#endif /* USE_PAM */