9345eed27afb6103c48a02d741f7602271f2fe62
[kai/samba.git] / source3 / auth / pampass.c
1 /* 
2    Unix SMB/CIFS implementation.
3    PAM Password checking
4    Copyright (C) Andrew Tridgell 1992-2001
5    Copyright (C) John H Terpsta 1999-2001
6    Copyright (C) Andrew Bartlett 2001
7    Copyright (C) Jeremy Allison 2001
8    
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13    
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18    
19    You should have received a copy of the GNU General Public License
20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
21 */
22
23 /*
24  * This module provides PAM based functions for validation of
25  * username/password pairs, account managment, session and access control.
26  * Note: SMB password checking is done in smbpass.c
27  */
28
29 #include "includes.h"
30
31 #undef DBGC_CLASS
32 #define DBGC_CLASS DBGC_AUTH
33
34 #ifdef WITH_PAM
35
36 /*******************************************************************
37  * Handle PAM authentication 
38  *      - Access, Authentication, Session, Password
39  *   Note: See PAM Documentation and refer to local system PAM implementation
40  *   which determines what actions/limitations/allowances become affected.
41  *********************************************************************/
42
43 #if defined(HAVE_SECURITY_PAM_APPL_H)
44 #include <security/pam_appl.h>
45 #elif defined(HAVE_PAM_PAM_APPL_H)
46 #include <pam/pam_appl.h>
47 #endif
48
49 /*
50  * Structure used to communicate between the conversation function
51  * and the server_login/change password functions.
52  */
53
54 struct smb_pam_userdata {
55         const char *PAM_username;
56         const char *PAM_password;
57         const char *PAM_newpassword;
58 };
59
60 typedef int (*smb_pam_conv_fn)(int, const struct pam_message **, struct pam_response **, void *appdata_ptr);
61
62 /*
63  *  Macros to help make life easy
64  */
65 #define COPY_STRING(s) (s) ? SMB_STRDUP(s) : NULL
66 #define COPY_FSTRING(s) (s[0]) ? SMB_STRDUP(s) : NULL
67
68 /*******************************************************************
69  PAM error handler.
70  *********************************************************************/
71
72 static bool smb_pam_error_handler(pam_handle_t *pamh, int pam_error, const char *msg, int dbglvl)
73 {
74
75         if( pam_error != PAM_SUCCESS) {
76                 DEBUG(dbglvl, ("smb_pam_error_handler: PAM: %s : %s\n",
77                                 msg, pam_strerror(pamh, pam_error)));
78                 
79                 return False;
80         }
81         return True;
82 }
83
84 /*******************************************************************
85  This function is a sanity check, to make sure that we NEVER report
86  failure as sucess.
87 *********************************************************************/
88
89 static bool smb_pam_nt_status_error_handler(pam_handle_t *pamh, int pam_error,
90                                             const char *msg, int dbglvl, 
91                                             NTSTATUS *nt_status)
92 {
93         *nt_status = pam_to_nt_status(pam_error);
94
95         if (smb_pam_error_handler(pamh, pam_error, msg, dbglvl))
96                 return True;
97
98         if (NT_STATUS_IS_OK(*nt_status)) {
99                 /* Complain LOUDLY */
100                 DEBUG(0, ("smb_pam_nt_status_error_handler: PAM: BUG: PAM and NT_STATUS \
101 error MISMATCH, forcing to NT_STATUS_LOGON_FAILURE"));
102                 *nt_status = NT_STATUS_LOGON_FAILURE;
103         }
104         return False;
105 }
106
107 /*
108  * PAM conversation function
109  * Here we assume (for now, at least) that echo on means login name, and
110  * echo off means password.
111  */
112
113 static int smb_pam_conv(int num_msg,
114                     const struct pam_message **msg,
115                     struct pam_response **resp,
116                     void *appdata_ptr)
117 {
118         int replies = 0;
119         struct pam_response *reply = NULL;
120         struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
121
122         *resp = NULL;
123
124         if (num_msg <= 0)
125                 return PAM_CONV_ERR;
126
127         /*
128          * Apparantly HPUX has a buggy PAM that doesn't support the
129          * appdata_ptr. Fail if this is the case. JRA.
130          */
131
132         if (udp == NULL) {
133                 DEBUG(0,("smb_pam_conv: PAM on this system is broken - appdata_ptr == NULL !\n"));
134                 return PAM_CONV_ERR;
135         }
136
137         reply = SMB_MALLOC_ARRAY(struct pam_response, num_msg);
138         if (!reply)
139                 return PAM_CONV_ERR;
140
141         memset(reply, '\0', sizeof(struct pam_response) * num_msg);
142
143         for (replies = 0; replies < num_msg; replies++) {
144                 switch (msg[replies]->msg_style) {
145                         case PAM_PROMPT_ECHO_ON:
146                                 reply[replies].resp_retcode = PAM_SUCCESS;
147                                 reply[replies].resp = COPY_STRING(udp->PAM_username);
148                                 /* PAM frees resp */
149                                 break;
150
151                         case PAM_PROMPT_ECHO_OFF:
152                                 reply[replies].resp_retcode = PAM_SUCCESS;
153                                 reply[replies].resp = COPY_STRING(udp->PAM_password);
154                                 /* PAM frees resp */
155                                 break;
156
157                         case PAM_TEXT_INFO:
158                                 /* fall through */
159
160                         case PAM_ERROR_MSG:
161                                 /* ignore it... */
162                                 reply[replies].resp_retcode = PAM_SUCCESS;
163                                 reply[replies].resp = NULL;
164                                 break;
165
166                         default:
167                                 /* Must be an error of some sort... */
168                                 SAFE_FREE(reply);
169                                 return PAM_CONV_ERR;
170                 }
171         }
172         if (reply)
173                 *resp = reply;
174         return PAM_SUCCESS;
175 }
176
177 /*
178  * PAM password change conversation function
179  * Here we assume (for now, at least) that echo on means login name, and
180  * echo off means password.
181  */
182
183 static void special_char_sub(char *buf)
184 {
185         all_string_sub(buf, "\\n", "", 0);
186         all_string_sub(buf, "\\r", "", 0);
187         all_string_sub(buf, "\\s", " ", 0);
188         all_string_sub(buf, "\\t", "\t", 0);
189 }
190
191 static void pwd_sub(char *buf, const char *username, const char *oldpass, const char *newpass)
192 {
193         fstring_sub(buf, "%u", username);
194         all_string_sub(buf, "%o", oldpass, sizeof(fstring));
195         all_string_sub(buf, "%n", newpass, sizeof(fstring));
196 }
197
198
199 struct chat_struct {
200         struct chat_struct *next, *prev;
201         fstring prompt;
202         fstring reply;
203 };
204
205 /**************************************************************
206  Create a linked list containing chat data.
207 ***************************************************************/
208
209 static struct chat_struct *make_pw_chat(const char *p) 
210 {
211         char *prompt;
212         char *reply;
213         struct chat_struct *list = NULL;
214         struct chat_struct *t;
215         TALLOC_CTX *frame = talloc_stackframe();
216
217         while (1) {
218                 t = SMB_MALLOC_P(struct chat_struct);
219                 if (!t) {
220                         DEBUG(0,("make_pw_chat: malloc failed!\n"));
221                         TALLOC_FREE(frame);
222                         return NULL;
223                 }
224
225                 ZERO_STRUCTP(t);
226
227                 DLIST_ADD_END(list, t, struct chat_struct*);
228
229                 if (!next_token_talloc(frame, &p, &prompt, NULL)) {
230                         break;
231                 }
232
233                 if (strequal(prompt,".")) {
234                         fstrcpy(prompt,"*");
235                 }
236
237                 special_char_sub(prompt);
238                 fstrcpy(t->prompt, prompt);
239                 strlower_m(t->prompt);
240                 trim_char(t->prompt, ' ', ' ');
241
242                 if (!next_token_talloc(frame, &p, &reply, NULL)) {
243                         break;
244                 }
245
246                 if (strequal(reply,".")) {
247                         fstrcpy(reply,"");
248                 }
249
250                 special_char_sub(reply);
251                 fstrcpy(t->reply, reply);
252                 strlower_m(t->reply);
253                 trim_char(t->reply, ' ', ' ');
254
255         }
256         TALLOC_FREE(frame);
257         return list;
258 }
259
260 static void free_pw_chat(struct chat_struct *list)
261 {
262     while (list) {
263         struct chat_struct *old_head = list;
264         DLIST_REMOVE(list, list);
265         SAFE_FREE(old_head);
266     }
267 }
268
269 static int smb_pam_passchange_conv(int num_msg,
270                                 const struct pam_message **msg,
271                                 struct pam_response **resp,
272                                 void *appdata_ptr)
273 {
274         int replies = 0;
275         struct pam_response *reply = NULL;
276         fstring current_prompt;
277         fstring current_reply;
278         struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
279         struct chat_struct *pw_chat= make_pw_chat(lp_passwd_chat());
280         struct chat_struct *t;
281         bool found; 
282         *resp = NULL;
283         
284         DEBUG(10,("smb_pam_passchange_conv: starting converstation for %d messages\n", num_msg));
285
286         if (num_msg <= 0)
287                 return PAM_CONV_ERR;
288
289         if (pw_chat == NULL)
290                 return PAM_CONV_ERR;
291
292         /*
293          * Apparantly HPUX has a buggy PAM that doesn't support the
294          * appdata_ptr. Fail if this is the case. JRA.
295          */
296
297         if (udp == NULL) {
298                 DEBUG(0,("smb_pam_passchange_conv: PAM on this system is broken - appdata_ptr == NULL !\n"));
299                 free_pw_chat(pw_chat);
300                 return PAM_CONV_ERR;
301         }
302
303         reply = SMB_MALLOC_ARRAY(struct pam_response, num_msg);
304         if (!reply) {
305                 DEBUG(0,("smb_pam_passchange_conv: malloc for reply failed!\n"));
306                 free_pw_chat(pw_chat);
307                 return PAM_CONV_ERR;
308         }
309
310         for (replies = 0; replies < num_msg; replies++) {
311                 found = False;
312                 DEBUG(10,("smb_pam_passchange_conv: Processing message %d\n", replies));
313                 switch (msg[replies]->msg_style) {
314                 case PAM_PROMPT_ECHO_ON:
315                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: PAM said: %s\n", msg[replies]->msg));
316                         fstrcpy(current_prompt, msg[replies]->msg);
317                         trim_char(current_prompt, ' ', ' ');
318                         for (t=pw_chat; t; t=t->next) {
319
320                                 DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: trying to match |%s| to |%s|\n",
321                                                 t->prompt, current_prompt ));
322
323                                 if (unix_wild_match(t->prompt, current_prompt)) {
324                                         fstrcpy(current_reply, t->reply);
325                                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: We sent: %s\n", current_reply));
326                                         pwd_sub(current_reply, udp->PAM_username, udp->PAM_password, udp->PAM_newpassword);
327 #ifdef DEBUG_PASSWORD
328                                         DEBUG(100,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: We actualy sent: %s\n", current_reply));
329 #endif
330                                         reply[replies].resp_retcode = PAM_SUCCESS;
331                                         reply[replies].resp = COPY_FSTRING(current_reply);
332                                         found = True;
333                                         break;
334                                 }
335                         }
336                         /* PAM frees resp */
337                         if (!found) {
338                                 DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
339                                 free_pw_chat(pw_chat);
340                                 SAFE_FREE(reply);
341                                 return PAM_CONV_ERR;
342                         }
343                         break;
344
345                 case PAM_PROMPT_ECHO_OFF:
346                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: PAM said: %s\n", msg[replies]->msg));
347                         fstrcpy(current_prompt, msg[replies]->msg);
348                         trim_char(current_prompt, ' ', ' ');
349                         for (t=pw_chat; t; t=t->next) {
350
351                                 DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: trying to match |%s| to |%s|\n",
352                                                 t->prompt, current_prompt ));
353
354                                 if (unix_wild_match(t->prompt, current_prompt)) {
355                                         fstrcpy(current_reply, t->reply);
356                                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: We sent: %s\n", current_reply));
357                                         pwd_sub(current_reply, udp->PAM_username, udp->PAM_password, udp->PAM_newpassword);
358                                         reply[replies].resp_retcode = PAM_SUCCESS;
359                                         reply[replies].resp = COPY_FSTRING(current_reply);
360 #ifdef DEBUG_PASSWORD
361                                         DEBUG(100,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: We actualy sent: %s\n", current_reply));
362 #endif
363                                         found = True;
364                                         break;
365                                 }
366                         }
367                         /* PAM frees resp */
368                         
369                         if (!found) {
370                                 DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
371                                 free_pw_chat(pw_chat);
372                                 SAFE_FREE(reply);
373                                 return PAM_CONV_ERR;
374                         }
375                         break;
376
377                 case PAM_TEXT_INFO:
378                         /* fall through */
379
380                 case PAM_ERROR_MSG:
381                         /* ignore it... */
382                         reply[replies].resp_retcode = PAM_SUCCESS;
383                         reply[replies].resp = NULL;
384                         break;
385                         
386                 default:
387                         /* Must be an error of some sort... */
388                         free_pw_chat(pw_chat);
389                         SAFE_FREE(reply);
390                         return PAM_CONV_ERR;
391                 }
392         }
393                 
394         free_pw_chat(pw_chat);
395         if (reply)
396                 *resp = reply;
397         return PAM_SUCCESS;
398 }
399
400 /***************************************************************************
401  Free up a malloced pam_conv struct.
402 ****************************************************************************/
403
404 static void smb_free_pam_conv(struct pam_conv *pconv)
405 {
406         if (pconv)
407                 SAFE_FREE(pconv->appdata_ptr);
408
409         SAFE_FREE(pconv);
410 }
411
412 /***************************************************************************
413  Allocate a pam_conv struct.
414 ****************************************************************************/
415
416 static struct pam_conv *smb_setup_pam_conv(smb_pam_conv_fn smb_pam_conv_fnptr, const char *user,
417                                         const char *passwd, const char *newpass)
418 {
419         struct pam_conv *pconv = SMB_MALLOC_P(struct pam_conv);
420         struct smb_pam_userdata *udp = SMB_MALLOC_P(struct smb_pam_userdata);
421
422         if (pconv == NULL || udp == NULL) {
423                 SAFE_FREE(pconv);
424                 SAFE_FREE(udp);
425                 return NULL;
426         }
427
428         udp->PAM_username = user;
429         udp->PAM_password = passwd;
430         udp->PAM_newpassword = newpass;
431
432         pconv->conv = smb_pam_conv_fnptr;
433         pconv->appdata_ptr = (void *)udp;
434         return pconv;
435 }
436
437 /* 
438  * PAM Closing out cleanup handler
439  */
440
441 static bool smb_pam_end(pam_handle_t *pamh, struct pam_conv *smb_pam_conv_ptr)
442 {
443         int pam_error;
444
445         smb_free_pam_conv(smb_pam_conv_ptr);
446        
447         if( pamh != NULL ) {
448                 pam_error = pam_end(pamh, 0);
449                 if(smb_pam_error_handler(pamh, pam_error, "End Cleanup Failed", 2) == True) {
450                         DEBUG(4, ("smb_pam_end: PAM: PAM_END OK.\n"));
451                         return True;
452                 }
453         }
454         DEBUG(2,("smb_pam_end: PAM: not initialised"));
455         return False;
456 }
457
458 /*
459  * Start PAM authentication for specified account
460  */
461
462 static bool smb_pam_start(pam_handle_t **pamh, const char *user, const char *rhost, struct pam_conv *pconv)
463 {
464         int pam_error;
465         const char *our_rhost;
466         char addr[INET6_ADDRSTRLEN];
467
468         *pamh = (pam_handle_t *)NULL;
469
470         DEBUG(4,("smb_pam_start: PAM: Init user: %s\n", user));
471
472         pam_error = pam_start("samba", user, pconv, pamh);
473         if( !smb_pam_error_handler(*pamh, pam_error, "Init Failed", 0)) {
474                 *pamh = (pam_handle_t *)NULL;
475                 return False;
476         }
477
478         if (rhost == NULL) {
479                 our_rhost = client_name(get_client_fd());
480                 if (strequal(our_rhost,"UNKNOWN"))
481                         our_rhost = client_addr(get_client_fd(),addr,sizeof(addr));
482         } else {
483                 our_rhost = rhost;
484         }
485
486 #ifdef PAM_RHOST
487         DEBUG(4,("smb_pam_start: PAM: setting rhost to: %s\n", our_rhost));
488         pam_error = pam_set_item(*pamh, PAM_RHOST, our_rhost);
489         if(!smb_pam_error_handler(*pamh, pam_error, "set rhost failed", 0)) {
490                 smb_pam_end(*pamh, pconv);
491                 *pamh = (pam_handle_t *)NULL;
492                 return False;
493         }
494 #endif
495 #ifdef PAM_TTY
496         DEBUG(4,("smb_pam_start: PAM: setting tty\n"));
497         pam_error = pam_set_item(*pamh, PAM_TTY, "samba");
498         if (!smb_pam_error_handler(*pamh, pam_error, "set tty failed", 0)) {
499                 smb_pam_end(*pamh, pconv);
500                 *pamh = (pam_handle_t *)NULL;
501                 return False;
502         }
503 #endif
504         DEBUG(4,("smb_pam_start: PAM: Init passed for user: %s\n", user));
505         return True;
506 }
507
508 /*
509  * PAM Authentication Handler
510  */
511 static NTSTATUS smb_pam_auth(pam_handle_t *pamh, const char *user)
512 {
513         int pam_error;
514         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
515
516         /*
517          * To enable debugging set in /etc/pam.d/samba:
518          *      auth required /lib/security/pam_pwdb.so nullok shadow audit
519          */
520         
521         DEBUG(4,("smb_pam_auth: PAM: Authenticate User: %s\n", user));
522         pam_error = pam_authenticate(pamh, PAM_SILENT | lp_null_passwords() ? 0 : PAM_DISALLOW_NULL_AUTHTOK);
523         switch( pam_error ){
524                 case PAM_AUTH_ERR:
525                         DEBUG(2, ("smb_pam_auth: PAM: Authentication Error for user %s\n", user));
526                         break;
527                 case PAM_CRED_INSUFFICIENT:
528                         DEBUG(2, ("smb_pam_auth: PAM: Insufficient Credentials for user %s\n", user));
529                         break;
530                 case PAM_AUTHINFO_UNAVAIL:
531                         DEBUG(2, ("smb_pam_auth: PAM: Authentication Information Unavailable for user %s\n", user));
532                         break;
533                 case PAM_USER_UNKNOWN:
534                         DEBUG(2, ("smb_pam_auth: PAM: Username %s NOT known to Authentication system\n", user));
535                         break;
536                 case PAM_MAXTRIES:
537                         DEBUG(2, ("smb_pam_auth: PAM: One or more authentication modules reports user limit for user %s exceeeded\n", user));
538                         break;
539                 case PAM_ABORT:
540                         DEBUG(0, ("smb_pam_auth: PAM: One or more PAM modules failed to load for user %s\n", user));
541                         break;
542                 case PAM_SUCCESS:
543                         DEBUG(4, ("smb_pam_auth: PAM: User %s Authenticated OK\n", user));
544                         break;
545                 default:
546                         DEBUG(0, ("smb_pam_auth: PAM: UNKNOWN ERROR while authenticating user %s\n", user));
547                         break;
548         }
549
550         smb_pam_nt_status_error_handler(pamh, pam_error, "Authentication Failure", 2, &nt_status);
551         return nt_status;
552 }
553
554 /* 
555  * PAM Account Handler
556  */
557 static NTSTATUS smb_pam_account(pam_handle_t *pamh, const char * user)
558 {
559         int pam_error;
560         NTSTATUS nt_status = NT_STATUS_ACCOUNT_DISABLED;
561
562         DEBUG(4,("smb_pam_account: PAM: Account Management for User: %s\n", user));
563         pam_error = pam_acct_mgmt(pamh, PAM_SILENT); /* Is user account enabled? */
564         switch( pam_error ) {
565                 case PAM_AUTHTOK_EXPIRED:
566                         DEBUG(2, ("smb_pam_account: PAM: User %s is valid but password is expired\n", user));
567                         break;
568                 case PAM_ACCT_EXPIRED:
569                         DEBUG(2, ("smb_pam_account: PAM: User %s no longer permitted to access system\n", user));
570                         break;
571                 case PAM_AUTH_ERR:
572                         DEBUG(2, ("smb_pam_account: PAM: There was an authentication error for user %s\n", user));
573                         break;
574                 case PAM_PERM_DENIED:
575                         DEBUG(0, ("smb_pam_account: PAM: User %s is NOT permitted to access system at this time\n", user));
576                         break;
577                 case PAM_USER_UNKNOWN:
578                         DEBUG(0, ("smb_pam_account: PAM: User \"%s\" is NOT known to account management\n", user));
579                         break;
580                 case PAM_SUCCESS:
581                         DEBUG(4, ("smb_pam_account: PAM: Account OK for User: %s\n", user));
582                         break;
583                 default:
584                         DEBUG(0, ("smb_pam_account: PAM: UNKNOWN PAM ERROR (%d) during Account Management for User: %s\n", pam_error, user));
585                         break;
586         }
587
588         smb_pam_nt_status_error_handler(pamh, pam_error, "Account Check Failed", 2, &nt_status);
589         return nt_status;
590 }
591
592 /*
593  * PAM Credential Setting
594  */
595
596 static NTSTATUS smb_pam_setcred(pam_handle_t *pamh, const char * user)
597 {
598         int pam_error;
599         NTSTATUS nt_status = NT_STATUS_NO_TOKEN;
600
601         /*
602          * This will allow samba to aquire a kerberos token. And, when
603          * exporting an AFS cell, be able to /write/ to this cell.
604          */
605
606         DEBUG(4,("PAM: Account Management SetCredentials for User: %s\n", user));
607         pam_error = pam_setcred(pamh, (PAM_ESTABLISH_CRED|PAM_SILENT)); 
608         switch( pam_error ) {
609                 case PAM_CRED_UNAVAIL:
610                         DEBUG(0, ("smb_pam_setcred: PAM: Credentials not found for user:%s\n", user ));
611                         break;
612                 case PAM_CRED_EXPIRED:
613                         DEBUG(0, ("smb_pam_setcred: PAM: Credentials for user: \"%s\" EXPIRED!\n", user ));
614                         break;
615                 case PAM_USER_UNKNOWN:
616                         DEBUG(0, ("smb_pam_setcred: PAM: User: \"%s\" is NOT known so can not set credentials!\n", user ));
617                         break;
618                 case PAM_CRED_ERR:
619                         DEBUG(0, ("smb_pam_setcred: PAM: Unknown setcredentials error - unable to set credentials for %s\n", user ));
620                         break;
621                 case PAM_SUCCESS:
622                         DEBUG(4, ("smb_pam_setcred: PAM: SetCredentials OK for User: %s\n", user));
623                         break;
624                 default:
625                         DEBUG(0, ("smb_pam_setcred: PAM: UNKNOWN PAM ERROR (%d) during SetCredentials for User: %s\n", pam_error, user));
626                         break;
627         }
628
629         smb_pam_nt_status_error_handler(pamh, pam_error, "Set Credential Failure", 2, &nt_status);
630         return nt_status;
631 }
632
633 /*
634  * PAM Internal Session Handler
635  */
636 static bool smb_internal_pam_session(pam_handle_t *pamh, const char *user, const char *tty, bool flag)
637 {
638         int pam_error;
639
640 #ifdef PAM_TTY
641         DEBUG(4,("smb_internal_pam_session: PAM: tty set to: %s\n", tty));
642         pam_error = pam_set_item(pamh, PAM_TTY, tty);
643         if (!smb_pam_error_handler(pamh, pam_error, "set tty failed", 0))
644                 return False;
645 #endif
646
647         if (flag) {
648                 pam_error = pam_open_session(pamh, PAM_SILENT);
649                 if (!smb_pam_error_handler(pamh, pam_error, "session setup failed", 0))
650                         return False;
651         } else {
652                 pam_setcred(pamh, (PAM_DELETE_CRED|PAM_SILENT)); /* We don't care if this fails */
653                 pam_error = pam_close_session(pamh, PAM_SILENT); /* This will probably pick up the error anyway */
654                 if (!smb_pam_error_handler(pamh, pam_error, "session close failed", 0))
655                         return False;
656         }
657         return (True);
658 }
659
660 /*
661  * Internal PAM Password Changer.
662  */
663
664 static bool smb_pam_chauthtok(pam_handle_t *pamh, const char * user)
665 {
666         int pam_error;
667
668         DEBUG(4,("smb_pam_chauthtok: PAM: Password Change for User: %s\n", user));
669
670         pam_error = pam_chauthtok(pamh, PAM_SILENT); /* Change Password */
671
672         switch( pam_error ) {
673         case PAM_AUTHTOK_ERR:
674                 DEBUG(2, ("PAM: unable to obtain the new authentication token - is password to weak?\n"));
675                 break;
676
677         /* This doesn't seem to be defined on Solaris. JRA */
678 #ifdef PAM_AUTHTOK_RECOVER_ERR
679         case PAM_AUTHTOK_RECOVER_ERR:
680                 DEBUG(2, ("PAM: unable to obtain the old authentication token - was the old password wrong?.\n"));
681                 break;
682 #endif
683
684         case PAM_AUTHTOK_LOCK_BUSY:
685                 DEBUG(2, ("PAM: unable to change the authentication token since it is currently locked.\n"));
686                 break;
687         case PAM_AUTHTOK_DISABLE_AGING:
688                 DEBUG(2, ("PAM: Authentication token aging has been disabled.\n"));
689                 break;
690         case PAM_PERM_DENIED:
691                 DEBUG(0, ("PAM: Permission denied.\n"));
692                 break;
693         case PAM_TRY_AGAIN:
694                 DEBUG(0, ("PAM: Could not update all authentication token(s). No authentication tokens were updated.\n"));
695                 break;
696         case PAM_USER_UNKNOWN:
697                 DEBUG(0, ("PAM: User not known to PAM\n"));
698                 break;
699         case PAM_SUCCESS:
700                 DEBUG(4, ("PAM: Account OK for User: %s\n", user));
701                 break;
702         default:
703                 DEBUG(0, ("PAM: UNKNOWN PAM ERROR (%d) for User: %s\n", pam_error, user));
704         }
705  
706         if(!smb_pam_error_handler(pamh, pam_error, "Password Change Failed", 2)) {
707                 return False;
708         }
709
710         /* If this point is reached, the password has changed. */
711         return True;
712 }
713
714 /*
715  * PAM Externally accessible Session handler
716  */
717
718 bool smb_pam_claim_session(char *user, char *tty, char *rhost)
719 {
720         pam_handle_t *pamh = NULL;
721         struct pam_conv *pconv = NULL;
722
723         /* Ignore PAM if told to. */
724
725         if (!lp_obey_pam_restrictions())
726                 return True;
727
728         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
729                 return False;
730
731         if (!smb_pam_start(&pamh, user, rhost, pconv))
732                 return False;
733
734         if (!smb_internal_pam_session(pamh, user, tty, True)) {
735                 smb_pam_end(pamh, pconv);
736                 return False;
737         }
738
739         return smb_pam_end(pamh, pconv);
740 }
741
742 /*
743  * PAM Externally accessible Session handler
744  */
745
746 bool smb_pam_close_session(char *user, char *tty, char *rhost)
747 {
748         pam_handle_t *pamh = NULL;
749         struct pam_conv *pconv = NULL;
750
751         /* Ignore PAM if told to. */
752
753         if (!lp_obey_pam_restrictions())
754                 return True;
755
756         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
757                 return False;
758
759         if (!smb_pam_start(&pamh, user, rhost, pconv))
760                 return False;
761
762         if (!smb_internal_pam_session(pamh, user, tty, False)) {
763                 smb_pam_end(pamh, pconv);
764                 return False;
765         }
766
767         return smb_pam_end(pamh, pconv);
768 }
769
770 /*
771  * PAM Externally accessible Account handler
772  */
773
774 NTSTATUS smb_pam_accountcheck(const char * user)
775 {
776         NTSTATUS nt_status = NT_STATUS_ACCOUNT_DISABLED;
777         pam_handle_t *pamh = NULL;
778         struct pam_conv *pconv = NULL;
779
780         /* Ignore PAM if told to. */
781
782         if (!lp_obey_pam_restrictions())
783                 return NT_STATUS_OK;
784
785         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
786                 return NT_STATUS_NO_MEMORY;
787
788         if (!smb_pam_start(&pamh, user, NULL, pconv))
789                 return NT_STATUS_ACCOUNT_DISABLED;
790
791         if (!NT_STATUS_IS_OK(nt_status = smb_pam_account(pamh, user)))
792                 DEBUG(0, ("smb_pam_accountcheck: PAM: Account Validation Failed - Rejecting User %s!\n", user));
793
794         smb_pam_end(pamh, pconv);
795         return nt_status;
796 }
797
798 /*
799  * PAM Password Validation Suite
800  */
801
802 NTSTATUS smb_pam_passcheck(const char * user, const char * password)
803 {
804         pam_handle_t *pamh = NULL;
805         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
806         struct pam_conv *pconv = NULL;
807
808         /*
809          * Note we can't ignore PAM here as this is the only
810          * way of doing auths on plaintext passwords when
811          * compiled --with-pam.
812          */
813
814         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, password, NULL)) == NULL)
815                 return NT_STATUS_LOGON_FAILURE;
816
817         if (!smb_pam_start(&pamh, user, NULL, pconv))
818                 return NT_STATUS_LOGON_FAILURE;
819
820         if (!NT_STATUS_IS_OK(nt_status = smb_pam_auth(pamh, user))) {
821                 DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_auth failed - Rejecting User %s !\n", user));
822                 smb_pam_end(pamh, pconv);
823                 return nt_status;
824         }
825
826         if (!NT_STATUS_IS_OK(nt_status = smb_pam_account(pamh, user))) {
827                 DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_account failed - Rejecting User %s !\n", user));
828                 smb_pam_end(pamh, pconv);
829                 return nt_status;
830         }
831
832         if (!NT_STATUS_IS_OK(nt_status = smb_pam_setcred(pamh, user))) {
833                 DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_setcred failed - Rejecting User %s !\n", user));
834                 smb_pam_end(pamh, pconv);
835                 return nt_status;
836         }
837
838         smb_pam_end(pamh, pconv);
839         return nt_status;
840 }
841
842 /*
843  * PAM Password Change Suite
844  */
845
846 bool smb_pam_passchange(const char * user, const char * oldpassword, const char * newpassword)
847 {
848         /* Appropriate quantities of root should be obtained BEFORE calling this function */
849         struct pam_conv *pconv = NULL;
850         pam_handle_t *pamh = NULL;
851
852         if ((pconv = smb_setup_pam_conv(smb_pam_passchange_conv, user, oldpassword, newpassword)) == NULL)
853                 return False;
854
855         if(!smb_pam_start(&pamh, user, NULL, pconv))
856                 return False;
857
858         if (!smb_pam_chauthtok(pamh, user)) {
859                 DEBUG(0, ("smb_pam_passchange: PAM: Password Change Failed for user %s!\n", user));
860                 smb_pam_end(pamh, pconv);
861                 return False;
862         }
863
864         return smb_pam_end(pamh, pconv);
865 }
866
867 #else
868
869 /* If PAM not used, no PAM restrictions on accounts. */
870 NTSTATUS smb_pam_accountcheck(const char * user)
871 {
872         return NT_STATUS_OK;
873 }
874
875 /* If PAM not used, also no PAM restrictions on sessions. */
876 bool smb_pam_claim_session(char *user, char *tty, char *rhost)
877 {
878         return True;
879 }
880
881 /* If PAM not used, also no PAM restrictions on sessions. */
882 bool smb_pam_close_session(char *in_user, char *tty, char *rhost)
883 {
884         return True;
885 }
886 #endif /* WITH_PAM */