2 * Copyright (c) 2002 Networks Associates Technology, Inc.
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.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
32 * Copyright (c) 2003,2004 Damien Miller <djm@mindrot.org>
33 * Copyright (c) 2003,2004 Darren Tucker <dtucker@zip.com.au>
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.
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.
48 /* Based on $xFreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */
50 RCSID("$Id: auth-pam.c,v 1.122 2005/05/25 06:18:10 dtucker Exp $");
54 #if defined(HAVE_SECURITY_PAM_APPL_H)
55 #include <security/pam_appl.h>
56 #elif defined (HAVE_PAM_PAM_APPL_H)
57 #include <pam/pam_appl.h>
66 #include "monitor_wrap.h"
73 #include "auth-options.h"
75 extern ServerOptions options;
76 extern Buffer loginmsg;
78 extern u_int utmp_len;
80 /* so we don't silently change behaviour */
81 #ifdef USE_POSIX_THREADS
82 # error "USE_POSIX_THREADS replaced by UNSUPPORTED_POSIX_THREADS_HACK"
86 * Formerly known as USE_POSIX_THREADS, using this is completely unsupported
87 * and generally a bad idea. Use at own risk and do not expect support if
90 #ifdef UNSUPPORTED_POSIX_THREADS_HACK
93 * Avoid namespace clash when *not* using pthreads for systems *with*
94 * pthreads, which unconditionally define pthread_t via sys/types.h
97 typedef pthread_t sp_pthread_t;
99 typedef pid_t sp_pthread_t;
103 sp_pthread_t pam_thread;
109 static void sshpam_free_ctx(void *);
110 static struct pam_ctxt *cleanup_ctxt;
112 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
114 * Simulate threads with processes.
117 static int sshpam_thread_status = -1;
118 static mysig_t sshpam_oldsig;
121 sshpam_sigchld_handler(int sig)
123 signal(SIGCHLD, SIG_DFL);
124 if (cleanup_ctxt == NULL)
125 return; /* handler called after PAM cleanup, shouldn't happen */
126 if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, WNOHANG)
128 /* PAM thread has not exitted, privsep slave must have */
129 kill(cleanup_ctxt->pam_thread, SIGTERM);
130 if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0)
132 return; /* could not wait */
134 if (WIFSIGNALED(sshpam_thread_status) &&
135 WTERMSIG(sshpam_thread_status) == SIGTERM)
136 return; /* terminated by pthread_cancel */
137 if (!WIFEXITED(sshpam_thread_status))
138 fatal("PAM: authentication thread exited unexpectedly");
139 if (WEXITSTATUS(sshpam_thread_status) != 0)
140 fatal("PAM: authentication thread exited uncleanly");
144 pthread_exit(void *value __unused)
150 pthread_create(sp_pthread_t *thread, const void *attr __unused,
151 void *(*thread_start)(void *), void *arg)
155 sshpam_thread_status = -1;
156 switch ((pid = fork())) {
158 error("fork(): %s", strerror(errno));
165 sshpam_oldsig = signal(SIGCHLD, sshpam_sigchld_handler);
171 pthread_cancel(sp_pthread_t thread)
173 signal(SIGCHLD, sshpam_oldsig);
174 return (kill(thread, SIGTERM));
178 pthread_join(sp_pthread_t thread, void **value __unused)
182 if (sshpam_thread_status != -1)
183 return (sshpam_thread_status);
184 signal(SIGCHLD, sshpam_oldsig);
185 waitpid(thread, &status, 0);
191 static pam_handle_t *sshpam_handle = NULL;
192 static int sshpam_err = 0;
193 static int sshpam_authenticated = 0;
194 static int sshpam_session_open = 0;
195 static int sshpam_cred_established = 0;
196 static int sshpam_account_status = -1;
197 static char **sshpam_env = NULL;
198 static Authctxt *sshpam_authctxt = NULL;
199 static const char *sshpam_password = NULL;
200 static char badpw[] = "\b\n\r\177INCORRECT";
202 /* Some PAM implementations don't implement this */
203 #ifndef HAVE_PAM_GETENVLIST
205 pam_getenvlist(pam_handle_t *pamh)
208 * XXX - If necessary, we can still support envrionment passing
209 * for platforms without pam_getenvlist by searching for known
210 * env vars (e.g. KRB5CCNAME) from the PAM environment.
217 * Some platforms, notably Solaris, do not enforce password complexity
218 * rules during pam_chauthtok() if the real uid of the calling process
219 * is 0, on the assumption that it's being called by "passwd" run by root.
220 * This wraps pam_chauthtok and sets/restore the real uid so PAM will do
223 #ifdef SSHPAM_CHAUTHTOK_NEEDS_RUID
225 sshpam_chauthtok_ruid(pam_handle_t *pamh, int flags)
229 if (sshpam_authctxt == NULL)
230 fatal("PAM: sshpam_authctxt not initialized");
231 if (setreuid(sshpam_authctxt->pw->pw_uid, -1) == -1)
232 fatal("%s: setreuid failed: %s", __func__, strerror(errno));
233 result = pam_chauthtok(pamh, flags);
234 if (setreuid(0, -1) == -1)
235 fatal("%s: setreuid failed: %s", __func__, strerror(errno));
238 # define pam_chauthtok(a,b) (sshpam_chauthtok_ruid((a), (b)))
242 sshpam_password_change_required(int reqd)
244 debug3("%s %d", __func__, reqd);
245 if (sshpam_authctxt == NULL)
246 fatal("%s: PAM authctxt not initialized", __func__);
247 sshpam_authctxt->force_pwchange = reqd;
249 no_port_forwarding_flag |= 2;
250 no_agent_forwarding_flag |= 2;
251 no_x11_forwarding_flag |= 2;
253 no_port_forwarding_flag &= ~2;
254 no_agent_forwarding_flag &= ~2;
255 no_x11_forwarding_flag &= ~2;
259 /* Import regular and PAM environment from subprocess */
261 import_environments(Buffer *b)
267 debug3("PAM: %s entering", __func__);
269 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
270 /* Import variables set by do_pam_account */
271 sshpam_account_status = buffer_get_int(b);
272 sshpam_password_change_required(buffer_get_int(b));
274 /* Import environment from subprocess */
275 num_env = buffer_get_int(b);
276 sshpam_env = xmalloc((num_env + 1) * sizeof(*sshpam_env));
277 debug3("PAM: num env strings %d", num_env);
278 for(i = 0; i < num_env; i++)
279 sshpam_env[i] = buffer_get_string(b, NULL);
281 sshpam_env[num_env] = NULL;
283 /* Import PAM environment from subprocess */
284 num_env = buffer_get_int(b);
285 debug("PAM: num PAM env strings %d", num_env);
286 for(i = 0; i < num_env; i++) {
287 env = buffer_get_string(b, NULL);
289 #ifdef HAVE_PAM_PUTENV
290 /* Errors are not fatal here */
291 if ((err = pam_putenv(sshpam_handle, env)) != PAM_SUCCESS) {
292 error("PAM: pam_putenv: %s",
293 pam_strerror(sshpam_handle, sshpam_err));
301 * Conversation function for authentication thread.
304 sshpam_thread_conv(int n, struct pam_message **msg,
305 struct pam_response **resp, void *data)
308 struct pam_ctxt *ctxt;
309 struct pam_response *reply;
312 debug3("PAM: %s entering, %d messages", __func__, n);
316 error("PAM: conversation function passed a null context");
317 return (PAM_CONV_ERR);
320 if (n <= 0 || n > PAM_MAX_NUM_MSG)
321 return (PAM_CONV_ERR);
323 if ((reply = malloc(n * sizeof(*reply))) == NULL)
324 return (PAM_CONV_ERR);
325 memset(reply, 0, n * sizeof(*reply));
327 buffer_init(&buffer);
328 for (i = 0; i < n; ++i) {
329 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
330 case PAM_PROMPT_ECHO_OFF:
331 buffer_put_cstring(&buffer,
332 PAM_MSG_MEMBER(msg, i, msg));
333 if (ssh_msg_send(ctxt->pam_csock,
334 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
336 if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1)
338 if (buffer_get_char(&buffer) != PAM_AUTHTOK)
340 reply[i].resp = buffer_get_string(&buffer, NULL);
342 case PAM_PROMPT_ECHO_ON:
343 buffer_put_cstring(&buffer,
344 PAM_MSG_MEMBER(msg, i, msg));
345 if (ssh_msg_send(ctxt->pam_csock,
346 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
348 if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1)
350 if (buffer_get_char(&buffer) != PAM_AUTHTOK)
352 reply[i].resp = buffer_get_string(&buffer, NULL);
355 buffer_put_cstring(&buffer,
356 PAM_MSG_MEMBER(msg, i, msg));
357 if (ssh_msg_send(ctxt->pam_csock,
358 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
362 buffer_put_cstring(&buffer,
363 PAM_MSG_MEMBER(msg, i, msg));
364 if (ssh_msg_send(ctxt->pam_csock,
365 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
371 buffer_clear(&buffer);
373 buffer_free(&buffer);
375 return (PAM_SUCCESS);
378 for(i = 0; i < n; i++) {
379 if (reply[i].resp != NULL)
380 xfree(reply[i].resp);
383 buffer_free(&buffer);
384 return (PAM_CONV_ERR);
388 * Authentication thread.
391 sshpam_thread(void *ctxtp)
393 struct pam_ctxt *ctxt = ctxtp;
395 struct pam_conv sshpam_conv;
396 int flags = (options.permit_empty_passwd == 0 ?
397 PAM_DISALLOW_NULL_AUTHTOK : 0);
398 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
399 extern char **environ;
402 const char *pam_user;
404 pam_get_item(sshpam_handle, PAM_USER, (void **)&pam_user);
407 if (sshpam_authctxt != NULL) {
408 setproctitle("%s [pam]",
409 sshpam_authctxt->valid ? pam_user : "unknown");
413 sshpam_conv.conv = sshpam_thread_conv;
414 sshpam_conv.appdata_ptr = ctxt;
416 if (sshpam_authctxt == NULL)
417 fatal("%s: PAM authctxt not initialized", __func__);
419 buffer_init(&buffer);
420 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
421 (const void *)&sshpam_conv);
422 if (sshpam_err != PAM_SUCCESS)
424 sshpam_err = pam_authenticate(sshpam_handle, flags);
425 if (sshpam_err != PAM_SUCCESS)
429 if (!do_pam_account())
431 if (sshpam_authctxt->force_pwchange) {
432 sshpam_err = pam_chauthtok(sshpam_handle,
433 PAM_CHANGE_EXPIRED_AUTHTOK);
434 if (sshpam_err != PAM_SUCCESS)
436 sshpam_password_change_required(0);
440 buffer_put_cstring(&buffer, "OK");
442 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
443 /* Export variables set by do_pam_account */
444 buffer_put_int(&buffer, sshpam_account_status);
445 buffer_put_int(&buffer, sshpam_authctxt->force_pwchange);
447 /* Export any environment strings set in child */
448 for(i = 0; environ[i] != NULL; i++)
450 buffer_put_int(&buffer, i);
451 for(i = 0; environ[i] != NULL; i++)
452 buffer_put_cstring(&buffer, environ[i]);
454 /* Export any environment strings set by PAM in child */
455 env_from_pam = pam_getenvlist(sshpam_handle);
456 for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++)
458 buffer_put_int(&buffer, i);
459 for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++)
460 buffer_put_cstring(&buffer, env_from_pam[i]);
461 #endif /* UNSUPPORTED_POSIX_THREADS_HACK */
463 /* XXX - can't do much about an error here */
464 ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer);
465 buffer_free(&buffer);
469 buffer_put_cstring(&buffer,
470 pam_strerror(sshpam_handle, sshpam_err));
471 /* XXX - can't do much about an error here */
472 ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer);
473 buffer_free(&buffer);
476 return (NULL); /* Avoid warning for non-pthread case */
480 sshpam_thread_cleanup(void)
482 struct pam_ctxt *ctxt = cleanup_ctxt;
484 debug3("PAM: %s entering", __func__);
485 if (ctxt != NULL && ctxt->pam_thread != 0) {
486 pthread_cancel(ctxt->pam_thread);
487 pthread_join(ctxt->pam_thread, NULL);
488 close(ctxt->pam_psock);
489 close(ctxt->pam_csock);
490 memset(ctxt, 0, sizeof(*ctxt));
496 sshpam_null_conv(int n, struct pam_message **msg,
497 struct pam_response **resp, void *data)
499 debug3("PAM: %s entering, %d messages", __func__, n);
500 return (PAM_CONV_ERR);
503 static struct pam_conv null_conv = { sshpam_null_conv, NULL };
506 sshpam_store_conv(int n, struct pam_message **msg,
507 struct pam_response **resp, void *data)
509 struct pam_response *reply;
513 debug3("PAM: %s called with %d messages", __func__, n);
516 if (n <= 0 || n > PAM_MAX_NUM_MSG)
517 return (PAM_CONV_ERR);
519 if ((reply = malloc(n * sizeof(*reply))) == NULL)
520 return (PAM_CONV_ERR);
521 memset(reply, 0, n * sizeof(*reply));
523 for (i = 0; i < n; ++i) {
524 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
527 len = strlen(PAM_MSG_MEMBER(msg, i, msg));
528 buffer_append(&loginmsg, PAM_MSG_MEMBER(msg, i, msg), len);
529 buffer_append(&loginmsg, "\n", 1 );
530 reply[i].resp_retcode = PAM_SUCCESS;
537 return (PAM_SUCCESS);
540 for(i = 0; i < n; i++) {
541 if (reply[i].resp != NULL)
542 xfree(reply[i].resp);
545 return (PAM_CONV_ERR);
548 static struct pam_conv store_conv = { sshpam_store_conv, NULL };
553 debug("PAM: cleanup");
554 if (sshpam_handle == NULL)
556 pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
557 if (sshpam_cred_established) {
558 pam_setcred(sshpam_handle, PAM_DELETE_CRED);
559 sshpam_cred_established = 0;
561 if (sshpam_session_open) {
562 pam_close_session(sshpam_handle, PAM_SILENT);
563 sshpam_session_open = 0;
565 sshpam_authenticated = 0;
566 pam_end(sshpam_handle, sshpam_err);
567 sshpam_handle = NULL;
571 sshpam_init(Authctxt *authctxt)
573 extern char *__progname;
574 const char *pam_rhost, *pam_user, *user = authctxt->user;
576 if (sshpam_handle != NULL) {
577 /* We already have a PAM context; check if the user matches */
578 sshpam_err = pam_get_item(sshpam_handle,
579 PAM_USER, (void **)&pam_user);
580 if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0)
582 pam_end(sshpam_handle, sshpam_err);
583 sshpam_handle = NULL;
585 debug("PAM: initializing for \"%s\"", user);
587 pam_start(SSHD_PAM_SERVICE, user, &store_conv, &sshpam_handle);
588 sshpam_authctxt = authctxt;
590 if (sshpam_err != PAM_SUCCESS) {
591 pam_end(sshpam_handle, sshpam_err);
592 sshpam_handle = NULL;
595 pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns);
596 debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost);
597 sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost);
598 if (sshpam_err != PAM_SUCCESS) {
599 pam_end(sshpam_handle, sshpam_err);
600 sshpam_handle = NULL;
603 #ifdef PAM_TTY_KLUDGE
605 * Some silly PAM modules (e.g. pam_time) require a TTY to operate.
606 * sshd doesn't set the tty until too late in the auth process and
607 * may not even set one (for tty-less connections)
609 debug("PAM: setting PAM_TTY to \"ssh\"");
610 sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, "ssh");
611 if (sshpam_err != PAM_SUCCESS) {
612 pam_end(sshpam_handle, sshpam_err);
613 sshpam_handle = NULL;
621 sshpam_init_ctx(Authctxt *authctxt)
623 struct pam_ctxt *ctxt;
626 debug3("PAM: %s entering", __func__);
627 /* Refuse to start if we don't have PAM enabled */
628 if (!options.use_pam)
632 if (sshpam_init(authctxt) == -1) {
633 error("PAM: initialization failed");
637 ctxt = xmalloc(sizeof *ctxt);
638 memset(ctxt, 0, sizeof(*ctxt));
640 /* Start the authentication thread */
641 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) {
642 error("PAM: failed create sockets: %s", strerror(errno));
646 ctxt->pam_psock = socks[0];
647 ctxt->pam_csock = socks[1];
648 if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) {
649 error("PAM: failed to start authentication thread: %s",
661 sshpam_query(void *ctx, char **name, char **info,
662 u_int *num, char ***prompts, u_int **echo_on)
665 struct pam_ctxt *ctxt = ctx;
671 debug3("PAM: %s entering", __func__);
672 buffer_init(&buffer);
675 *prompts = xmalloc(sizeof(char *));
678 *echo_on = xmalloc(sizeof(u_int));
679 while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) {
680 type = buffer_get_char(&buffer);
681 msg = buffer_get_string(&buffer, NULL);
684 case PAM_PROMPT_ECHO_ON:
685 case PAM_PROMPT_ECHO_OFF:
687 len = plen + mlen + 1;
688 **prompts = xrealloc(**prompts, len);
689 strlcpy(**prompts + plen, msg, len - plen);
691 **echo_on = (type == PAM_PROMPT_ECHO_ON);
696 /* accumulate messages */
697 len = plen + mlen + 2;
698 **prompts = xrealloc(**prompts, len);
699 strlcpy(**prompts + plen, msg, len - plen);
701 strlcat(**prompts + plen, "\n", len - plen);
707 if (**prompts != NULL) {
708 /* drain any accumulated messages */
709 debug("PAM: %s", **prompts);
710 buffer_append(&loginmsg, **prompts,
715 if (type == PAM_SUCCESS) {
716 if (!sshpam_authctxt->valid ||
717 (sshpam_authctxt->pw->pw_uid == 0 &&
718 options.permit_root_login != PERMIT_YES))
719 fatal("Internal error: PAM auth "
720 "succeeded when it should have "
722 import_environments(&buffer);
729 error("PAM: %s for %s%.100s from %.100s", msg,
730 sshpam_authctxt->valid ? "" : "illegal user ",
731 sshpam_authctxt->user,
732 get_remote_name_or_ip(utmp_len, options.use_dns));
745 /* XXX - see also comment in auth-chall.c:verify_response */
747 sshpam_respond(void *ctx, u_int num, char **resp)
750 struct pam_ctxt *ctxt = ctx;
752 debug2("PAM: %s entering, %d responses", __func__, num);
753 switch (ctxt->pam_done) {
755 sshpam_authenticated = 1;
763 error("PAM: expected one response, got %u", num);
766 buffer_init(&buffer);
767 if (sshpam_authctxt->valid &&
768 (sshpam_authctxt->pw->pw_uid != 0 ||
769 options.permit_root_login == PERMIT_YES))
770 buffer_put_cstring(&buffer, *resp);
772 buffer_put_cstring(&buffer, badpw);
773 if (ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer) == -1) {
774 buffer_free(&buffer);
777 buffer_free(&buffer);
782 sshpam_free_ctx(void *ctxtp)
784 struct pam_ctxt *ctxt = ctxtp;
786 debug3("PAM: %s entering", __func__);
787 sshpam_thread_cleanup();
790 * We don't call sshpam_cleanup() here because we may need the PAM
791 * handle at a later stage, e.g. when setting up a session. It's
792 * still on the cleanup list, so pam_end() *will* be called before
793 * the server process terminates.
797 KbdintDevice sshpam_device = {
805 KbdintDevice mm_sshpam_device = {
814 * This replaces auth-pam.c
817 start_pam(Authctxt *authctxt)
819 if (!options.use_pam)
820 fatal("PAM: initialisation requested when UsePAM=no");
822 if (sshpam_init(authctxt) == -1)
823 fatal("PAM: initialisation failed");
835 debug("%s: called", __func__);
836 if (sshpam_account_status != -1)
837 return (sshpam_account_status);
839 sshpam_err = pam_acct_mgmt(sshpam_handle, 0);
840 debug3("PAM: %s pam_acct_mgmt = %d (%s)", __func__, sshpam_err,
841 pam_strerror(sshpam_handle, sshpam_err));
843 if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD) {
844 sshpam_account_status = 0;
845 return (sshpam_account_status);
848 if (sshpam_err == PAM_NEW_AUTHTOK_REQD)
849 sshpam_password_change_required(1);
851 sshpam_account_status = 1;
852 return (sshpam_account_status);
856 do_pam_set_tty(const char *tty)
859 debug("PAM: setting PAM_TTY to \"%s\"", tty);
860 sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty);
861 if (sshpam_err != PAM_SUCCESS)
862 fatal("PAM: failed to set PAM_TTY: %s",
863 pam_strerror(sshpam_handle, sshpam_err));
868 do_pam_setcred(int init)
870 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
871 (const void *)&store_conv);
872 if (sshpam_err != PAM_SUCCESS)
873 fatal("PAM: failed to set PAM_CONV: %s",
874 pam_strerror(sshpam_handle, sshpam_err));
876 debug("PAM: establishing credentials");
877 sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED);
879 debug("PAM: reinitializing credentials");
880 sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED);
882 if (sshpam_err == PAM_SUCCESS) {
883 sshpam_cred_established = 1;
886 if (sshpam_authenticated)
887 fatal("PAM: pam_setcred(): %s",
888 pam_strerror(sshpam_handle, sshpam_err));
890 debug("PAM: pam_setcred(): %s",
891 pam_strerror(sshpam_handle, sshpam_err));
895 sshpam_tty_conv(int n, struct pam_message **msg,
896 struct pam_response **resp, void *data)
898 char input[PAM_MAX_MSG_SIZE];
899 struct pam_response *reply;
902 debug3("PAM: %s called with %d messages", __func__, n);
906 if (n <= 0 || n > PAM_MAX_NUM_MSG || !isatty(STDIN_FILENO))
907 return (PAM_CONV_ERR);
909 if ((reply = malloc(n * sizeof(*reply))) == NULL)
910 return (PAM_CONV_ERR);
911 memset(reply, 0, n * sizeof(*reply));
913 for (i = 0; i < n; ++i) {
914 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
915 case PAM_PROMPT_ECHO_OFF:
917 read_passphrase(PAM_MSG_MEMBER(msg, i, msg),
919 reply[i].resp_retcode = PAM_SUCCESS;
921 case PAM_PROMPT_ECHO_ON:
922 fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
923 fgets(input, sizeof input, stdin);
924 if ((reply[i].resp = strdup(input)) == NULL)
926 reply[i].resp_retcode = PAM_SUCCESS;
930 fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
931 reply[i].resp_retcode = PAM_SUCCESS;
938 return (PAM_SUCCESS);
941 for(i = 0; i < n; i++) {
942 if (reply[i].resp != NULL)
943 xfree(reply[i].resp);
946 return (PAM_CONV_ERR);
949 static struct pam_conv tty_conv = { sshpam_tty_conv, NULL };
952 * XXX this should be done in the authentication phase, but ssh1 doesn't
956 do_pam_chauthtok(void)
959 fatal("Password expired (unable to change with privsep)");
960 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
961 (const void *)&tty_conv);
962 if (sshpam_err != PAM_SUCCESS)
963 fatal("PAM: failed to set PAM_CONV: %s",
964 pam_strerror(sshpam_handle, sshpam_err));
965 debug("PAM: changing password");
966 sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK);
967 if (sshpam_err != PAM_SUCCESS)
968 fatal("PAM: pam_chauthtok(): %s",
969 pam_strerror(sshpam_handle, sshpam_err));
975 debug3("PAM: opening session");
976 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
977 (const void *)&store_conv);
978 if (sshpam_err != PAM_SUCCESS)
979 fatal("PAM: failed to set PAM_CONV: %s",
980 pam_strerror(sshpam_handle, sshpam_err));
981 sshpam_err = pam_open_session(sshpam_handle, 0);
982 if (sshpam_err == PAM_SUCCESS)
983 sshpam_session_open = 1;
985 sshpam_session_open = 0;
986 disable_forwarding();
987 error("PAM: pam_open_session(): %s",
988 pam_strerror(sshpam_handle, sshpam_err));
994 is_pam_session_open(void)
996 return sshpam_session_open;
1000 * Set a PAM environment string. We need to do this so that the session
1001 * modules can handle things like Kerberos/GSI credentials that appear
1002 * during the ssh authentication process.
1005 do_pam_putenv(char *name, char *value)
1008 #ifdef HAVE_PAM_PUTENV
1012 len = strlen(name) + strlen(value) + 2;
1013 compound = xmalloc(len);
1015 snprintf(compound, len, "%s=%s", name, value);
1016 ret = pam_putenv(sshpam_handle, compound);
1024 fetch_pam_child_environment(void)
1030 fetch_pam_environment(void)
1032 return (pam_getenvlist(sshpam_handle));
1036 free_pam_environment(char **env)
1043 for (envp = env; *envp; envp++)
1049 * "Blind" conversation function for password authentication. Assumes that
1050 * echo-off prompts are for the password and stores messages for later
1054 sshpam_passwd_conv(int n, struct pam_message **msg,
1055 struct pam_response **resp, void *data)
1057 struct pam_response *reply;
1061 debug3("PAM: %s called with %d messages", __func__, n);
1065 if (n <= 0 || n > PAM_MAX_NUM_MSG)
1066 return (PAM_CONV_ERR);
1068 if ((reply = malloc(n * sizeof(*reply))) == NULL)
1069 return (PAM_CONV_ERR);
1070 memset(reply, 0, n * sizeof(*reply));
1072 for (i = 0; i < n; ++i) {
1073 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
1074 case PAM_PROMPT_ECHO_OFF:
1075 if (sshpam_password == NULL)
1077 if ((reply[i].resp = strdup(sshpam_password)) == NULL)
1079 reply[i].resp_retcode = PAM_SUCCESS;
1083 len = strlen(PAM_MSG_MEMBER(msg, i, msg));
1085 buffer_append(&loginmsg,
1086 PAM_MSG_MEMBER(msg, i, msg), len);
1087 buffer_append(&loginmsg, "\n", 1);
1089 if ((reply[i].resp = strdup("")) == NULL)
1091 reply[i].resp_retcode = PAM_SUCCESS;
1098 return (PAM_SUCCESS);
1101 for(i = 0; i < n; i++) {
1102 if (reply[i].resp != NULL)
1103 xfree(reply[i].resp);
1106 return (PAM_CONV_ERR);
1109 static struct pam_conv passwd_conv = { sshpam_passwd_conv, NULL };
1112 * Attempt password authentication via PAM
1115 sshpam_auth_passwd(Authctxt *authctxt, const char *password)
1117 int flags = (options.permit_empty_passwd == 0 ?
1118 PAM_DISALLOW_NULL_AUTHTOK : 0);
1120 if (!options.use_pam || sshpam_handle == NULL)
1121 fatal("PAM: %s called when PAM disabled or failed to "
1122 "initialise.", __func__);
1124 sshpam_password = password;
1125 sshpam_authctxt = authctxt;
1128 * If the user logging in is invalid, or is root but is not permitted
1129 * by PermitRootLogin, use an invalid password to prevent leaking
1130 * information via timing (eg if the PAM config has a delay on fail).
1132 if (!authctxt->valid || (authctxt->pw->pw_uid == 0 &&
1133 options.permit_root_login != PERMIT_YES))
1134 sshpam_password = badpw;
1136 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
1137 (const void *)&passwd_conv);
1138 if (sshpam_err != PAM_SUCCESS)
1139 fatal("PAM: %s: failed to set PAM_CONV: %s", __func__,
1140 pam_strerror(sshpam_handle, sshpam_err));
1142 sshpam_err = pam_authenticate(sshpam_handle, flags);
1143 sshpam_password = NULL;
1144 if (sshpam_err == PAM_SUCCESS && authctxt->valid) {
1145 debug("PAM: password authentication accepted for %.100s",
1149 debug("PAM: password authentication failed for %.100s: %s",
1150 authctxt->valid ? authctxt->user : "an illegal user",
1151 pam_strerror(sshpam_handle, sshpam_err));
1155 #endif /* USE_PAM */