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 $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */
51 #include <sys/types.h>
57 #if defined(HAVE_SECURITY_PAM_APPL_H)
58 #include <security/pam_appl.h>
59 #elif defined (HAVE_PAM_PAM_APPL_H)
60 #include <pam/pam_appl.h>
63 /* OpenGroup RFC86.0 and XSSO specify no "const" on arguments */
64 #ifdef PAM_SUN_CODEBASE
65 # define sshpam_const /* Solaris, HP-UX, AIX */
67 # define sshpam_const const /* LinuxPAM, OpenPAM */
76 #include "monitor_wrap.h"
83 #include "auth-options.h"
85 extern ServerOptions options;
86 extern Buffer loginmsg;
88 extern u_int utmp_len;
90 /* so we don't silently change behaviour */
91 #ifdef USE_POSIX_THREADS
92 # error "USE_POSIX_THREADS replaced by UNSUPPORTED_POSIX_THREADS_HACK"
96 * Formerly known as USE_POSIX_THREADS, using this is completely unsupported
97 * and generally a bad idea. Use at own risk and do not expect support if
100 #ifdef UNSUPPORTED_POSIX_THREADS_HACK
103 * Avoid namespace clash when *not* using pthreads for systems *with*
104 * pthreads, which unconditionally define pthread_t via sys/types.h
107 typedef pthread_t sp_pthread_t;
109 typedef pid_t sp_pthread_t;
113 sp_pthread_t pam_thread;
119 static void sshpam_free_ctx(void *);
120 static struct pam_ctxt *cleanup_ctxt;
122 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
124 * Simulate threads with processes.
127 static int sshpam_thread_status = -1;
128 static mysig_t sshpam_oldsig;
131 sshpam_sigchld_handler(int sig)
133 signal(SIGCHLD, SIG_DFL);
134 if (cleanup_ctxt == NULL)
135 return; /* handler called after PAM cleanup, shouldn't happen */
136 if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, WNOHANG)
138 /* PAM thread has not exitted, privsep slave must have */
139 kill(cleanup_ctxt->pam_thread, SIGTERM);
140 if (waitpid(cleanup_ctxt->pam_thread, &sshpam_thread_status, 0)
142 return; /* could not wait */
144 if (WIFSIGNALED(sshpam_thread_status) &&
145 WTERMSIG(sshpam_thread_status) == SIGTERM)
146 return; /* terminated by pthread_cancel */
147 if (!WIFEXITED(sshpam_thread_status))
148 fatal("PAM: authentication thread exited unexpectedly");
149 if (WEXITSTATUS(sshpam_thread_status) != 0)
150 fatal("PAM: authentication thread exited uncleanly");
154 pthread_exit(void *value __unused)
160 pthread_create(sp_pthread_t *thread, const void *attr __unused,
161 void *(*thread_start)(void *), void *arg)
164 struct pam_ctxt *ctx = arg;
166 sshpam_thread_status = -1;
167 switch ((pid = fork())) {
169 error("fork(): %s", strerror(errno));
172 close(ctx->pam_psock);
178 close(ctx->pam_csock);
180 sshpam_oldsig = signal(SIGCHLD, sshpam_sigchld_handler);
186 pthread_cancel(sp_pthread_t thread)
188 signal(SIGCHLD, sshpam_oldsig);
189 return (kill(thread, SIGTERM));
193 pthread_join(sp_pthread_t thread, void **value __unused)
197 if (sshpam_thread_status != -1)
198 return (sshpam_thread_status);
199 signal(SIGCHLD, sshpam_oldsig);
200 waitpid(thread, &status, 0);
206 static pam_handle_t *sshpam_handle = NULL;
207 static int sshpam_err = 0;
208 static int sshpam_authenticated = 0;
209 static int sshpam_session_open = 0;
210 static int sshpam_cred_established = 0;
211 static int sshpam_account_status = -1;
212 static char **sshpam_env = NULL;
213 static Authctxt *sshpam_authctxt = NULL;
214 static const char *sshpam_password = NULL;
215 static char badpw[] = "\b\n\r\177INCORRECT";
217 /* Some PAM implementations don't implement this */
218 #ifndef HAVE_PAM_GETENVLIST
220 pam_getenvlist(pam_handle_t *pamh)
223 * XXX - If necessary, we can still support envrionment passing
224 * for platforms without pam_getenvlist by searching for known
225 * env vars (e.g. KRB5CCNAME) from the PAM environment.
232 * Some platforms, notably Solaris, do not enforce password complexity
233 * rules during pam_chauthtok() if the real uid of the calling process
234 * is 0, on the assumption that it's being called by "passwd" run by root.
235 * This wraps pam_chauthtok and sets/restore the real uid so PAM will do
238 #ifdef SSHPAM_CHAUTHTOK_NEEDS_RUID
240 sshpam_chauthtok_ruid(pam_handle_t *pamh, int flags)
244 if (sshpam_authctxt == NULL)
245 fatal("PAM: sshpam_authctxt not initialized");
246 if (setreuid(sshpam_authctxt->pw->pw_uid, -1) == -1)
247 fatal("%s: setreuid failed: %s", __func__, strerror(errno));
248 result = pam_chauthtok(pamh, flags);
249 if (setreuid(0, -1) == -1)
250 fatal("%s: setreuid failed: %s", __func__, strerror(errno));
253 # define pam_chauthtok(a,b) (sshpam_chauthtok_ruid((a), (b)))
257 sshpam_password_change_required(int reqd)
259 debug3("%s %d", __func__, reqd);
260 if (sshpam_authctxt == NULL)
261 fatal("%s: PAM authctxt not initialized", __func__);
262 sshpam_authctxt->force_pwchange = reqd;
264 no_port_forwarding_flag |= 2;
265 no_agent_forwarding_flag |= 2;
266 no_x11_forwarding_flag |= 2;
268 no_port_forwarding_flag &= ~2;
269 no_agent_forwarding_flag &= ~2;
270 no_x11_forwarding_flag &= ~2;
274 /* Import regular and PAM environment from subprocess */
276 import_environments(Buffer *b)
282 debug3("PAM: %s entering", __func__);
284 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
285 /* Import variables set by do_pam_account */
286 sshpam_account_status = buffer_get_int(b);
287 sshpam_password_change_required(buffer_get_int(b));
289 /* Import environment from subprocess */
290 num_env = buffer_get_int(b);
292 fatal("%s: received %u environment variables, expected <= 1024",
294 sshpam_env = xcalloc(num_env + 1, sizeof(*sshpam_env));
295 debug3("PAM: num env strings %d", num_env);
296 for(i = 0; i < num_env; i++)
297 sshpam_env[i] = buffer_get_string(b, NULL);
299 sshpam_env[num_env] = NULL;
301 /* Import PAM environment from subprocess */
302 num_env = buffer_get_int(b);
303 debug("PAM: num PAM env strings %d", num_env);
304 for(i = 0; i < num_env; i++) {
305 env = buffer_get_string(b, NULL);
307 #ifdef HAVE_PAM_PUTENV
308 /* Errors are not fatal here */
309 if ((err = pam_putenv(sshpam_handle, env)) != PAM_SUCCESS) {
310 error("PAM: pam_putenv: %s",
311 pam_strerror(sshpam_handle, sshpam_err));
319 * Conversation function for authentication thread.
322 sshpam_thread_conv(int n, sshpam_const struct pam_message **msg,
323 struct pam_response **resp, void *data)
326 struct pam_ctxt *ctxt;
327 struct pam_response *reply;
330 debug3("PAM: %s entering, %d messages", __func__, n);
334 error("PAM: conversation function passed a null context");
335 return (PAM_CONV_ERR);
338 if (n <= 0 || n > PAM_MAX_NUM_MSG)
339 return (PAM_CONV_ERR);
341 if ((reply = calloc(n, sizeof(*reply))) == NULL)
342 return (PAM_CONV_ERR);
344 buffer_init(&buffer);
345 for (i = 0; i < n; ++i) {
346 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
347 case PAM_PROMPT_ECHO_OFF:
348 buffer_put_cstring(&buffer,
349 PAM_MSG_MEMBER(msg, i, msg));
350 if (ssh_msg_send(ctxt->pam_csock,
351 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
353 if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1)
355 if (buffer_get_char(&buffer) != PAM_AUTHTOK)
357 reply[i].resp = buffer_get_string(&buffer, NULL);
359 case PAM_PROMPT_ECHO_ON:
360 buffer_put_cstring(&buffer,
361 PAM_MSG_MEMBER(msg, i, msg));
362 if (ssh_msg_send(ctxt->pam_csock,
363 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
365 if (ssh_msg_recv(ctxt->pam_csock, &buffer) == -1)
367 if (buffer_get_char(&buffer) != PAM_AUTHTOK)
369 reply[i].resp = buffer_get_string(&buffer, NULL);
372 buffer_put_cstring(&buffer,
373 PAM_MSG_MEMBER(msg, i, msg));
374 if (ssh_msg_send(ctxt->pam_csock,
375 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
379 buffer_put_cstring(&buffer,
380 PAM_MSG_MEMBER(msg, i, msg));
381 if (ssh_msg_send(ctxt->pam_csock,
382 PAM_MSG_MEMBER(msg, i, msg_style), &buffer) == -1)
388 buffer_clear(&buffer);
390 buffer_free(&buffer);
392 return (PAM_SUCCESS);
395 for(i = 0; i < n; i++) {
396 if (reply[i].resp != NULL)
397 xfree(reply[i].resp);
400 buffer_free(&buffer);
401 return (PAM_CONV_ERR);
405 * Authentication thread.
408 sshpam_thread(void *ctxtp)
410 struct pam_ctxt *ctxt = ctxtp;
412 struct pam_conv sshpam_conv;
413 int flags = (options.permit_empty_passwd == 0 ?
414 PAM_DISALLOW_NULL_AUTHTOK : 0);
415 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
416 extern char **environ;
419 const char *pam_user;
420 const char **ptr_pam_user = &pam_user;
422 pam_get_item(sshpam_handle, PAM_USER,
423 (sshpam_const void **)ptr_pam_user);
426 if (sshpam_authctxt != NULL) {
427 setproctitle("%s [pam]",
428 sshpam_authctxt->valid ? pam_user : "unknown");
432 sshpam_conv.conv = sshpam_thread_conv;
433 sshpam_conv.appdata_ptr = ctxt;
435 if (sshpam_authctxt == NULL)
436 fatal("%s: PAM authctxt not initialized", __func__);
438 buffer_init(&buffer);
439 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
440 (const void *)&sshpam_conv);
441 if (sshpam_err != PAM_SUCCESS)
443 sshpam_err = pam_authenticate(sshpam_handle, flags);
444 if (sshpam_err != PAM_SUCCESS)
448 if (!do_pam_account())
450 if (sshpam_authctxt->force_pwchange) {
451 sshpam_err = pam_chauthtok(sshpam_handle,
452 PAM_CHANGE_EXPIRED_AUTHTOK);
453 if (sshpam_err != PAM_SUCCESS)
455 sshpam_password_change_required(0);
459 buffer_put_cstring(&buffer, "OK");
461 #ifndef UNSUPPORTED_POSIX_THREADS_HACK
462 /* Export variables set by do_pam_account */
463 buffer_put_int(&buffer, sshpam_account_status);
464 buffer_put_int(&buffer, sshpam_authctxt->force_pwchange);
466 /* Export any environment strings set in child */
467 for(i = 0; environ[i] != NULL; i++)
469 buffer_put_int(&buffer, i);
470 for(i = 0; environ[i] != NULL; i++)
471 buffer_put_cstring(&buffer, environ[i]);
473 /* Export any environment strings set by PAM in child */
474 env_from_pam = pam_getenvlist(sshpam_handle);
475 for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++)
477 buffer_put_int(&buffer, i);
478 for(i = 0; env_from_pam != NULL && env_from_pam[i] != NULL; i++)
479 buffer_put_cstring(&buffer, env_from_pam[i]);
480 #endif /* UNSUPPORTED_POSIX_THREADS_HACK */
482 /* XXX - can't do much about an error here */
483 ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer);
484 buffer_free(&buffer);
488 buffer_put_cstring(&buffer,
489 pam_strerror(sshpam_handle, sshpam_err));
490 /* XXX - can't do much about an error here */
491 ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer);
492 buffer_free(&buffer);
495 return (NULL); /* Avoid warning for non-pthread case */
499 sshpam_thread_cleanup(void)
501 struct pam_ctxt *ctxt = cleanup_ctxt;
503 debug3("PAM: %s entering", __func__);
504 if (ctxt != NULL && ctxt->pam_thread != 0) {
505 pthread_cancel(ctxt->pam_thread);
506 pthread_join(ctxt->pam_thread, NULL);
507 close(ctxt->pam_psock);
508 close(ctxt->pam_csock);
509 memset(ctxt, 0, sizeof(*ctxt));
515 sshpam_null_conv(int n, sshpam_const struct pam_message **msg,
516 struct pam_response **resp, void *data)
518 debug3("PAM: %s entering, %d messages", __func__, n);
519 return (PAM_CONV_ERR);
522 static struct pam_conv null_conv = { sshpam_null_conv, NULL };
525 sshpam_store_conv(int n, sshpam_const struct pam_message **msg,
526 struct pam_response **resp, void *data)
528 struct pam_response *reply;
532 debug3("PAM: %s called with %d messages", __func__, n);
535 if (n <= 0 || n > PAM_MAX_NUM_MSG)
536 return (PAM_CONV_ERR);
538 if ((reply = calloc(n, sizeof(*reply))) == NULL)
539 return (PAM_CONV_ERR);
541 for (i = 0; i < n; ++i) {
542 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
545 len = strlen(PAM_MSG_MEMBER(msg, i, msg));
546 buffer_append(&loginmsg, PAM_MSG_MEMBER(msg, i, msg), len);
547 buffer_append(&loginmsg, "\n", 1 );
548 reply[i].resp_retcode = PAM_SUCCESS;
555 return (PAM_SUCCESS);
558 for(i = 0; i < n; i++) {
559 if (reply[i].resp != NULL)
560 xfree(reply[i].resp);
563 return (PAM_CONV_ERR);
566 static struct pam_conv store_conv = { sshpam_store_conv, NULL };
571 debug("PAM: cleanup");
572 if (sshpam_handle == NULL)
574 pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
575 if (sshpam_cred_established) {
576 pam_setcred(sshpam_handle, PAM_DELETE_CRED);
577 sshpam_cred_established = 0;
579 if (sshpam_session_open) {
580 pam_close_session(sshpam_handle, PAM_SILENT);
581 sshpam_session_open = 0;
583 sshpam_authenticated = 0;
584 pam_end(sshpam_handle, sshpam_err);
585 sshpam_handle = NULL;
589 sshpam_init(Authctxt *authctxt)
591 extern char *__progname;
592 const char *pam_rhost, *pam_user, *user = authctxt->user;
593 const char **ptr_pam_user = &pam_user;
595 if (sshpam_handle != NULL) {
596 /* We already have a PAM context; check if the user matches */
597 sshpam_err = pam_get_item(sshpam_handle,
598 PAM_USER, (sshpam_const void **)ptr_pam_user);
599 if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0)
601 pam_end(sshpam_handle, sshpam_err);
602 sshpam_handle = NULL;
604 debug("PAM: initializing for \"%s\"", user);
606 pam_start(SSHD_PAM_SERVICE, user, &store_conv, &sshpam_handle);
607 sshpam_authctxt = authctxt;
609 if (sshpam_err != PAM_SUCCESS) {
610 pam_end(sshpam_handle, sshpam_err);
611 sshpam_handle = NULL;
614 pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns);
615 debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost);
616 sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost);
617 if (sshpam_err != PAM_SUCCESS) {
618 pam_end(sshpam_handle, sshpam_err);
619 sshpam_handle = NULL;
622 #ifdef PAM_TTY_KLUDGE
624 * Some silly PAM modules (e.g. pam_time) require a TTY to operate.
625 * sshd doesn't set the tty until too late in the auth process and
626 * may not even set one (for tty-less connections)
628 debug("PAM: setting PAM_TTY to \"ssh\"");
629 sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, "ssh");
630 if (sshpam_err != PAM_SUCCESS) {
631 pam_end(sshpam_handle, sshpam_err);
632 sshpam_handle = NULL;
640 sshpam_init_ctx(Authctxt *authctxt)
642 struct pam_ctxt *ctxt;
645 debug3("PAM: %s entering", __func__);
646 /* Refuse to start if we don't have PAM enabled */
647 if (!options.use_pam)
651 if (sshpam_init(authctxt) == -1) {
652 error("PAM: initialization failed");
656 ctxt = xmalloc(sizeof *ctxt);
657 memset(ctxt, 0, sizeof(*ctxt));
659 /* Start the authentication thread */
660 if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) {
661 error("PAM: failed create sockets: %s", strerror(errno));
665 ctxt->pam_psock = socks[0];
666 ctxt->pam_csock = socks[1];
667 if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) {
668 error("PAM: failed to start authentication thread: %s",
680 sshpam_query(void *ctx, char **name, char **info,
681 u_int *num, char ***prompts, u_int **echo_on)
684 struct pam_ctxt *ctxt = ctx;
690 debug3("PAM: %s entering", __func__);
691 buffer_init(&buffer);
694 *prompts = xmalloc(sizeof(char *));
697 *echo_on = xmalloc(sizeof(u_int));
698 while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) {
699 type = buffer_get_char(&buffer);
700 msg = buffer_get_string(&buffer, NULL);
703 case PAM_PROMPT_ECHO_ON:
704 case PAM_PROMPT_ECHO_OFF:
706 len = plen + mlen + 1;
707 **prompts = xrealloc(**prompts, 1, len);
708 strlcpy(**prompts + plen, msg, len - plen);
710 **echo_on = (type == PAM_PROMPT_ECHO_ON);
715 /* accumulate messages */
716 len = plen + mlen + 2;
717 **prompts = xrealloc(**prompts, 1, len);
718 strlcpy(**prompts + plen, msg, len - plen);
720 strlcat(**prompts + plen, "\n", len - plen);
725 debug3("PAM: PAM_AUTH_ERR");
726 if (**prompts != NULL && strlen(**prompts) != 0) {
737 if (**prompts != NULL) {
738 /* drain any accumulated messages */
739 debug("PAM: %s", **prompts);
740 buffer_append(&loginmsg, **prompts,
745 if (type == PAM_SUCCESS) {
746 if (!sshpam_authctxt->valid ||
747 (sshpam_authctxt->pw->pw_uid == 0 &&
748 options.permit_root_login != PERMIT_YES))
749 fatal("Internal error: PAM auth "
750 "succeeded when it should have "
752 import_environments(&buffer);
759 error("PAM: %s for %s%.100s from %.100s", msg,
760 sshpam_authctxt->valid ? "" : "illegal user ",
761 sshpam_authctxt->user,
762 get_remote_name_or_ip(utmp_len, options.use_dns));
775 /* XXX - see also comment in auth-chall.c:verify_response */
777 sshpam_respond(void *ctx, u_int num, char **resp)
780 struct pam_ctxt *ctxt = ctx;
782 debug2("PAM: %s entering, %u responses", __func__, num);
783 switch (ctxt->pam_done) {
785 sshpam_authenticated = 1;
793 error("PAM: expected one response, got %u", num);
796 buffer_init(&buffer);
797 if (sshpam_authctxt->valid &&
798 (sshpam_authctxt->pw->pw_uid != 0 ||
799 options.permit_root_login == PERMIT_YES))
800 buffer_put_cstring(&buffer, *resp);
802 buffer_put_cstring(&buffer, badpw);
803 if (ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer) == -1) {
804 buffer_free(&buffer);
807 buffer_free(&buffer);
812 sshpam_free_ctx(void *ctxtp)
814 struct pam_ctxt *ctxt = ctxtp;
816 debug3("PAM: %s entering", __func__);
817 sshpam_thread_cleanup();
820 * We don't call sshpam_cleanup() here because we may need the PAM
821 * handle at a later stage, e.g. when setting up a session. It's
822 * still on the cleanup list, so pam_end() *will* be called before
823 * the server process terminates.
827 KbdintDevice sshpam_device = {
835 KbdintDevice mm_sshpam_device = {
844 * This replaces auth-pam.c
847 start_pam(Authctxt *authctxt)
849 if (!options.use_pam)
850 fatal("PAM: initialisation requested when UsePAM=no");
852 if (sshpam_init(authctxt) == -1)
853 fatal("PAM: initialisation failed");
865 debug("%s: called", __func__);
866 if (sshpam_account_status != -1)
867 return (sshpam_account_status);
869 sshpam_err = pam_acct_mgmt(sshpam_handle, 0);
870 debug3("PAM: %s pam_acct_mgmt = %d (%s)", __func__, sshpam_err,
871 pam_strerror(sshpam_handle, sshpam_err));
873 if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD) {
874 sshpam_account_status = 0;
875 return (sshpam_account_status);
878 if (sshpam_err == PAM_NEW_AUTHTOK_REQD)
879 sshpam_password_change_required(1);
881 sshpam_account_status = 1;
882 return (sshpam_account_status);
886 do_pam_set_tty(const char *tty)
889 debug("PAM: setting PAM_TTY to \"%s\"", tty);
890 sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty);
891 if (sshpam_err != PAM_SUCCESS)
892 fatal("PAM: failed to set PAM_TTY: %s",
893 pam_strerror(sshpam_handle, sshpam_err));
898 do_pam_setcred(int init)
900 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
901 (const void *)&store_conv);
902 if (sshpam_err != PAM_SUCCESS)
903 fatal("PAM: failed to set PAM_CONV: %s",
904 pam_strerror(sshpam_handle, sshpam_err));
906 debug("PAM: establishing credentials");
907 sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED);
909 debug("PAM: reinitializing credentials");
910 sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED);
912 if (sshpam_err == PAM_SUCCESS) {
913 sshpam_cred_established = 1;
916 if (sshpam_authenticated)
917 fatal("PAM: pam_setcred(): %s",
918 pam_strerror(sshpam_handle, sshpam_err));
920 debug("PAM: pam_setcred(): %s",
921 pam_strerror(sshpam_handle, sshpam_err));
925 sshpam_tty_conv(int n, sshpam_const struct pam_message **msg,
926 struct pam_response **resp, void *data)
928 char input[PAM_MAX_MSG_SIZE];
929 struct pam_response *reply;
932 debug3("PAM: %s called with %d messages", __func__, n);
936 if (n <= 0 || n > PAM_MAX_NUM_MSG || !isatty(STDIN_FILENO))
937 return (PAM_CONV_ERR);
939 if ((reply = calloc(n, sizeof(*reply))) == NULL)
940 return (PAM_CONV_ERR);
942 for (i = 0; i < n; ++i) {
943 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
944 case PAM_PROMPT_ECHO_OFF:
946 read_passphrase(PAM_MSG_MEMBER(msg, i, msg),
948 reply[i].resp_retcode = PAM_SUCCESS;
950 case PAM_PROMPT_ECHO_ON:
951 fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
952 fgets(input, sizeof input, stdin);
953 if ((reply[i].resp = strdup(input)) == NULL)
955 reply[i].resp_retcode = PAM_SUCCESS;
959 fprintf(stderr, "%s\n", PAM_MSG_MEMBER(msg, i, msg));
960 reply[i].resp_retcode = PAM_SUCCESS;
967 return (PAM_SUCCESS);
970 for(i = 0; i < n; i++) {
971 if (reply[i].resp != NULL)
972 xfree(reply[i].resp);
975 return (PAM_CONV_ERR);
978 static struct pam_conv tty_conv = { sshpam_tty_conv, NULL };
981 * XXX this should be done in the authentication phase, but ssh1 doesn't
985 do_pam_chauthtok(void)
988 fatal("Password expired (unable to change with privsep)");
989 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
990 (const void *)&tty_conv);
991 if (sshpam_err != PAM_SUCCESS)
992 fatal("PAM: failed to set PAM_CONV: %s",
993 pam_strerror(sshpam_handle, sshpam_err));
994 debug("PAM: changing password");
995 sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK);
996 if (sshpam_err != PAM_SUCCESS)
997 fatal("PAM: pam_chauthtok(): %s",
998 pam_strerror(sshpam_handle, sshpam_err));
1002 do_pam_session(void)
1004 debug3("PAM: opening session");
1005 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
1006 (const void *)&store_conv);
1007 if (sshpam_err != PAM_SUCCESS)
1008 fatal("PAM: failed to set PAM_CONV: %s",
1009 pam_strerror(sshpam_handle, sshpam_err));
1010 sshpam_err = pam_open_session(sshpam_handle, 0);
1011 if (sshpam_err == PAM_SUCCESS)
1012 sshpam_session_open = 1;
1014 sshpam_session_open = 0;
1015 disable_forwarding();
1016 error("PAM: pam_open_session(): %s",
1017 pam_strerror(sshpam_handle, sshpam_err));
1023 is_pam_session_open(void)
1025 return sshpam_session_open;
1029 * Set a PAM environment string. We need to do this so that the session
1030 * modules can handle things like Kerberos/GSI credentials that appear
1031 * during the ssh authentication process.
1034 do_pam_putenv(char *name, char *value)
1037 #ifdef HAVE_PAM_PUTENV
1041 len = strlen(name) + strlen(value) + 2;
1042 compound = xmalloc(len);
1044 snprintf(compound, len, "%s=%s", name, value);
1045 ret = pam_putenv(sshpam_handle, compound);
1053 fetch_pam_child_environment(void)
1059 fetch_pam_environment(void)
1061 return (pam_getenvlist(sshpam_handle));
1065 free_pam_environment(char **env)
1072 for (envp = env; *envp; envp++)
1078 * "Blind" conversation function for password authentication. Assumes that
1079 * echo-off prompts are for the password and stores messages for later
1083 sshpam_passwd_conv(int n, sshpam_const struct pam_message **msg,
1084 struct pam_response **resp, void *data)
1086 struct pam_response *reply;
1090 debug3("PAM: %s called with %d messages", __func__, n);
1094 if (n <= 0 || n > PAM_MAX_NUM_MSG)
1095 return (PAM_CONV_ERR);
1097 if ((reply = malloc(n * sizeof(*reply))) == NULL)
1098 return (PAM_CONV_ERR);
1099 memset(reply, 0, n * sizeof(*reply));
1101 for (i = 0; i < n; ++i) {
1102 switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
1103 case PAM_PROMPT_ECHO_OFF:
1104 if (sshpam_password == NULL)
1106 if ((reply[i].resp = strdup(sshpam_password)) == NULL)
1108 reply[i].resp_retcode = PAM_SUCCESS;
1112 len = strlen(PAM_MSG_MEMBER(msg, i, msg));
1114 buffer_append(&loginmsg,
1115 PAM_MSG_MEMBER(msg, i, msg), len);
1116 buffer_append(&loginmsg, "\n", 1);
1118 if ((reply[i].resp = strdup("")) == NULL)
1120 reply[i].resp_retcode = PAM_SUCCESS;
1127 return (PAM_SUCCESS);
1130 for(i = 0; i < n; i++) {
1131 if (reply[i].resp != NULL)
1132 xfree(reply[i].resp);
1135 return (PAM_CONV_ERR);
1138 static struct pam_conv passwd_conv = { sshpam_passwd_conv, NULL };
1141 * Attempt password authentication via PAM
1144 sshpam_auth_passwd(Authctxt *authctxt, const char *password)
1146 int flags = (options.permit_empty_passwd == 0 ?
1147 PAM_DISALLOW_NULL_AUTHTOK : 0);
1149 if (!options.use_pam || sshpam_handle == NULL)
1150 fatal("PAM: %s called when PAM disabled or failed to "
1151 "initialise.", __func__);
1153 sshpam_password = password;
1154 sshpam_authctxt = authctxt;
1157 * If the user logging in is invalid, or is root but is not permitted
1158 * by PermitRootLogin, use an invalid password to prevent leaking
1159 * information via timing (eg if the PAM config has a delay on fail).
1161 if (!authctxt->valid || (authctxt->pw->pw_uid == 0 &&
1162 options.permit_root_login != PERMIT_YES))
1163 sshpam_password = badpw;
1165 sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
1166 (const void *)&passwd_conv);
1167 if (sshpam_err != PAM_SUCCESS)
1168 fatal("PAM: %s: failed to set PAM_CONV: %s", __func__,
1169 pam_strerror(sshpam_handle, sshpam_err));
1171 sshpam_err = pam_authenticate(sshpam_handle, flags);
1172 sshpam_password = NULL;
1173 if (sshpam_err == PAM_SUCCESS && authctxt->valid) {
1174 debug("PAM: password authentication accepted for %.100s",
1178 debug("PAM: password authentication failed for %.100s: %s",
1179 authctxt->valid ? authctxt->user : "an illegal user",
1180 pam_strerror(sshpam_handle, sshpam_err));
1184 #endif /* USE_PAM */