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 management, session and access control.
  26  * Note: SMB password checking is done in smbpass.c
  27  */
  28
  29 #include "includes.h"
  30 #include "auth.h"
  31 #include "../libcli/auth/pam_errors.h"
  32 #include "lib/util/string_wrappers.h"
  33
  34 #undef DBGC_CLASS
  35 #define DBGC_CLASS DBGC_AUTH
  36
  37 #ifdef WITH_PAM
  38
  39 /*******************************************************************
  40  * Handle PAM authentication
  41  *      - Access, Authentication, Session, Password
  42  *   Note: See PAM Documentation and refer to local system PAM implementation
  43  *   which determines what actions/limitations/allowances become affected.
  44  *********************************************************************/
  45
  46 #if defined(HAVE_SECURITY_PAM_APPL_H)
  47 #include <security/pam_appl.h>
  48 #elif defined(HAVE_PAM_PAM_APPL_H)
  49 #include <pam/pam_appl.h>
  50 #endif
  51
  52 /*
  53  * Structure used to communicate between the conversation function
  54  * and the server_login/change password functions.
  55  */
  56
  57 struct smb_pam_userdata {
  58         const char *PAM_username;
  59         const char *PAM_password;
  60         const char *PAM_newpassword;
  61 };
  62
  63 typedef int (*smb_pam_conv_fn)(int, const struct pam_message **, struct pam_response **, void *appdata_ptr);
  64
  65 static char *smb_pam_copy_string(const char *s)
  66 {
  67         if (s == NULL) {
  68                 return NULL;
  69         }
  70         return SMB_STRDUP(s);
  71 }
  72
  73 static char *smb_pam_copy_fstring(const char *s)
  74 {
  75         if (s[0] == '\0') {
  76                 return NULL;
  77         }
  78         return SMB_STRDUP(s);
  79 }
  80
  81 /*******************************************************************
  82  PAM error handler.
  83  *********************************************************************/
  84
  85 static bool smb_pam_error_handler(pam_handle_t *pamh, int pam_error, const char *msg, int dbglvl)
  86 {
  87
  88         if( pam_error != PAM_SUCCESS) {
  89                 DEBUG(dbglvl, ("smb_pam_error_handler: PAM: %s : %s\n",
  90                                 msg, pam_strerror(pamh, pam_error)));
  91                 return False;
  92         }
  93         return True;
  94 }
  95
  96 /*******************************************************************
  97  This function is a sanity check, to make sure that we NEVER report
  98  failure as success.
  99 *********************************************************************/
 100
 101 static bool smb_pam_nt_status_error_handler(pam_handle_t *pamh, int pam_error,
 102                                             const char *msg, int dbglvl,
 103                                             NTSTATUS *nt_status)
 104 {
 105         *nt_status = pam_to_nt_status(pam_error);
 106
 107         if (smb_pam_error_handler(pamh, pam_error, msg, dbglvl))
 108                 return True;
 109
 110         if (NT_STATUS_IS_OK(*nt_status)) {
 111                 /* Complain LOUDLY */
 112                 DEBUG(0, ("smb_pam_nt_status_error_handler: PAM: BUG: PAM and NT_STATUS \
 113 error MISMATCH, forcing to NT_STATUS_LOGON_FAILURE\n"));
 114                 *nt_status = NT_STATUS_LOGON_FAILURE;
 115         }
 116         return False;
 117 }
 118
 119 /*
 120  * PAM conversation function
 121  * Here we assume (for now, at least) that echo on means login name, and
 122  * echo off means password.
 123  */
 124
 125 static int smb_pam_conv(int num_msg,
 126                     const struct pam_message **msg,
 127                     struct pam_response **resp,
 128                     void *appdata_ptr)
 129 {
 130         int replies = 0;
 131         struct pam_response *reply = NULL;
 132         struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
 133
 134         if (resp != NULL) {
 135                 *resp = NULL;
 136         }
 137
 138         if (num_msg <= 0)
 139                 return PAM_CONV_ERR;
 140
 141         /*
 142          * Apparently HPUX has a buggy PAM that doesn't support the
 143          * appdata_ptr. Fail if this is the case. JRA.
 144          */
 145
 146         if (udp == NULL) {
 147                 DEBUG(0,("smb_pam_conv: PAM on this system is broken - appdata_ptr == NULL !\n"));
 148                 return PAM_CONV_ERR;
 149         }
 150
 151         reply = SMB_MALLOC_ARRAY(struct pam_response, num_msg);
 152         if (!reply)
 153                 return PAM_CONV_ERR;
 154
 155         memset(reply, '\0', sizeof(struct pam_response) * num_msg);
 156
 157         for (replies = 0; replies < num_msg; replies++) {
 158                 switch (msg[replies]->msg_style) {
 159                         case PAM_PROMPT_ECHO_ON:
 160                                 reply[replies].resp_retcode = PAM_SUCCESS;
 161                                 reply[replies].resp = smb_pam_copy_string(
 162                                         udp->PAM_username);
 163                                 /* PAM frees resp */
 164                                 break;
 165
 166                         case PAM_PROMPT_ECHO_OFF:
 167                                 reply[replies].resp_retcode = PAM_SUCCESS;
 168                                 reply[replies].resp = smb_pam_copy_string(
 169                                         udp->PAM_password);
 170                                 /* PAM frees resp */
 171                                 break;
 172
 173                         case PAM_TEXT_INFO:
 174                                 FALL_THROUGH;
 175
 176                         case PAM_ERROR_MSG:
 177                                 /* ignore it... */
 178                                 reply[replies].resp_retcode = PAM_SUCCESS;
 179                                 reply[replies].resp = NULL;
 180                                 break;
 181
 182                         default:
 183                                 /* Must be an error of some sort... */
 184                                 SAFE_FREE(reply);
 185                                 return PAM_CONV_ERR;
 186                 }
 187         }
 188         if (reply != NULL) {
 189                 if (resp != NULL) {
 190                         *resp = reply;
 191                 } else {
 192                         SAFE_FREE(reply);
 193                 }
 194         }
 195         return PAM_SUCCESS;
 196 }
 197
 198 /*
 199  * PAM password change conversation function
 200  * Here we assume (for now, at least) that echo on means login name, and
 201  * echo off means password.
 202  */
 203
 204 static void special_char_sub(char *buf)
 205 {
 206         all_string_sub(buf, "\\n", "", 0);
 207         all_string_sub(buf, "\\r", "", 0);
 208         all_string_sub(buf, "\\s", " ", 0);
 209         all_string_sub(buf, "\\t", "\t", 0);
 210 }
 211
 212 static void pwd_sub(char *buf, const char *username, const char *oldpass, const char *newpass)
 213 {
 214         string_sub(buf, "%u", username, sizeof(fstring));
 215         all_string_sub(buf, "%o", oldpass, sizeof(fstring));
 216         all_string_sub(buf, "%n", newpass, sizeof(fstring));
 217 }
 218
 219
 220 struct chat_struct {
 221         struct chat_struct *next, *prev;
 222         fstring prompt;
 223         fstring reply;
 224 };
 225
 226 /**************************************************************
 227  Create a linked list containing chat data.
 228 ***************************************************************/
 229
 230 static struct chat_struct *make_pw_chat(const char *p)
 231 {
 232         char *prompt;
 233         char *reply;
 234         struct chat_struct *list = NULL;
 235         struct chat_struct *t;
 236         TALLOC_CTX *frame = talloc_stackframe();
 237
 238         while (1) {
 239                 t = SMB_MALLOC_P(struct chat_struct);
 240                 if (!t) {
 241                         DEBUG(0,("make_pw_chat: malloc failed!\n"));
 242                         TALLOC_FREE(frame);
 243                         return NULL;
 244                 }
 245
 246                 ZERO_STRUCTP(t);
 247
 248                 DLIST_ADD_END(list, t);
 249
 250                 if (!next_token_talloc(frame, &p, &prompt, NULL)) {
 251                         break;
 252                 }
 253
 254                 if (strequal(prompt,".")) {
 255                         fstrcpy(prompt,"*");
 256                 }
 257
 258                 special_char_sub(prompt);
 259                 fstrcpy(t->prompt, prompt);
 260                 (void)strlower_m(t->prompt);
 261                 trim_char(t->prompt, ' ', ' ');
 262
 263                 if (!next_token_talloc(frame, &p, &reply, NULL)) {
 264                         break;
 265                 }
 266
 267                 if (strequal(reply,".")) {
 268                         fstrcpy(reply,"");
 269                 }
 270
 271                 special_char_sub(reply);
 272                 fstrcpy(t->reply, reply);
 273                 (void)strlower_m(t->reply);
 274                 trim_char(t->reply, ' ', ' ');
 275
 276         }
 277         TALLOC_FREE(frame);
 278         return list;
 279 }
 280
 281 static void free_pw_chat(struct chat_struct *list)
 282 {
 283     while (list) {
 284         struct chat_struct *old_head = list;
 285         DLIST_REMOVE(list, list);
 286         SAFE_FREE(old_head);
 287     }
 288 }
 289
 290 static int smb_pam_passchange_conv(int num_msg,
 291                                 const struct pam_message **msg,
 292                                 struct pam_response **resp,
 293                                 void *appdata_ptr)
 294 {
 295         int replies = 0;
 296         struct pam_response *reply = NULL;
 297         fstring current_prompt;
 298         fstring current_reply;
 299         struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
 300         struct chat_struct *pw_chat;
 301         struct chat_struct *t;
 302         const struct loadparm_substitution *lp_sub =
 303                 loadparm_s3_global_substitution();
 304         bool found;
 305         *resp = NULL;
 306
 307         DEBUG(10,("smb_pam_passchange_conv: starting conversation for %d messages\n", num_msg));
 308
 309         if (num_msg <= 0)
 310                 return PAM_CONV_ERR;
 311
 312         if ((pw_chat = make_pw_chat(lp_passwd_chat(talloc_tos(), lp_sub))) == NULL)
 313                 return PAM_CONV_ERR;
 314
 315         /*
 316          * Apparently HPUX has a buggy PAM that doesn't support the
 317          * appdata_ptr. Fail if this is the case. JRA.
 318          */
 319
 320         if (udp == NULL) {
 321                 DEBUG(0,("smb_pam_passchange_conv: PAM on this system is broken - appdata_ptr == NULL !\n"));
 322                 free_pw_chat(pw_chat);
 323                 return PAM_CONV_ERR;
 324         }
 325
 326         reply = SMB_MALLOC_ARRAY(struct pam_response, num_msg);
 327         if (!reply) {
 328                 DEBUG(0,("smb_pam_passchange_conv: malloc for reply failed!\n"));
 329                 free_pw_chat(pw_chat);
 330                 return PAM_CONV_ERR;
 331         }
 332
 333         for (replies = 0; replies < num_msg; replies++) {
 334                 found = False;
 335                 DEBUG(10,("smb_pam_passchange_conv: Processing message %d\n", replies));
 336                 switch (msg[replies]->msg_style) {
 337                 case PAM_PROMPT_ECHO_ON:
 338                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: PAM said: %s\n", msg[replies]->msg));
 339                         fstrcpy(current_prompt, msg[replies]->msg);
 340                         trim_char(current_prompt, ' ', ' ');
 341                         for (t=pw_chat; t; t=t->next) {
 342
 343                                 DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: trying to match |%s| to |%s|\n",
 344                                                 t->prompt, current_prompt ));
 345
 346                                 if (unix_wild_match(t->prompt, current_prompt)) {
 347                                         fstrcpy(current_reply, t->reply);
 348                                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: We sent: %s\n", current_reply));
 349                                         pwd_sub(current_reply, udp->PAM_username, udp->PAM_password, udp->PAM_newpassword);
 350 #ifdef DEBUG_PASSWORD
 351                                         DEBUG(100,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: We actually sent: %s\n", current_reply));
 352 #endif
 353                                         reply[replies].resp_retcode = PAM_SUCCESS;
 354                                         reply[replies].resp = smb_pam_copy_fstring(
 355                                                 current_reply);
 356                                         found = True;
 357                                         break;
 358                                 }
 359                         }
 360                         /* PAM frees resp */
 361                         if (!found) {
 362                                 DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
 363                                 free_pw_chat(pw_chat);
 364                                 SAFE_FREE(reply);
 365                                 return PAM_CONV_ERR;
 366                         }
 367                         break;
 368
 369                 case PAM_PROMPT_ECHO_OFF:
 370                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: PAM said: %s\n", msg[replies]->msg));
 371                         fstrcpy(current_prompt, msg[replies]->msg);
 372                         trim_char(current_prompt, ' ', ' ');
 373                         for (t=pw_chat; t; t=t->next) {
 374
 375                                 DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: trying to match |%s| to |%s|\n",
 376                                                 t->prompt, current_prompt ));
 377
 378                                 if (unix_wild_match(t->prompt, current_prompt)) {
 379                                         fstrcpy(current_reply, t->reply);
 380                                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: We sent: %s\n", current_reply));
 381                                         pwd_sub(current_reply, udp->PAM_username, udp->PAM_password, udp->PAM_newpassword);
 382                                         reply[replies].resp_retcode = PAM_SUCCESS;
 383                                         reply[replies].resp = smb_pam_copy_fstring(
 384                                                 current_reply);
 385 #ifdef DEBUG_PASSWORD
 386                                         DEBUG(100,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: We actually sent: %s\n", current_reply));
 387 #endif
 388                                         found = True;
 389                                         break;
 390                                 }
 391                         }
 392                         /* PAM frees resp */
 393
 394                         if (!found) {
 395                                 DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
 396                                 free_pw_chat(pw_chat);
 397                                 SAFE_FREE(reply);
 398                                 return PAM_CONV_ERR;
 399                         }
 400                         break;
 401
 402                 case PAM_TEXT_INFO:
 403                         FALL_THROUGH;
 404
 405                 case PAM_ERROR_MSG:
 406                         /* ignore it... */
 407                         reply[replies].resp_retcode = PAM_SUCCESS;
 408                         reply[replies].resp = NULL;
 409                         break;
 410
 411                 default:
 412                         /* Must be an error of some sort... */
 413                         free_pw_chat(pw_chat);
 414                         SAFE_FREE(reply);
 415                         return PAM_CONV_ERR;
 416                 }
 417         }
 418
 419         free_pw_chat(pw_chat);
 420         if (reply)
 421                 *resp = reply;
 422         return PAM_SUCCESS;
 423 }
 424
 425 /***************************************************************************
 426  Free up a malloced pam_conv struct.
 427 ****************************************************************************/
 428
 429 static void smb_free_pam_conv(struct pam_conv *pconv)
 430 {
 431         if (pconv)
 432                 SAFE_FREE(pconv->appdata_ptr);
 433
 434         SAFE_FREE(pconv);
 435 }
 436
 437 /***************************************************************************
 438  Allocate a pam_conv struct.
 439 ****************************************************************************/
 440
 441 static struct pam_conv *smb_setup_pam_conv(smb_pam_conv_fn smb_pam_conv_fnptr, const char *user,
 442                                         const char *passwd, const char *newpass)
 443 {
 444         struct pam_conv *pconv = SMB_MALLOC_P(struct pam_conv);
 445         struct smb_pam_userdata *udp = SMB_MALLOC_P(struct smb_pam_userdata);
 446
 447         if (pconv == NULL || udp == NULL) {
 448                 SAFE_FREE(pconv);
 449                 SAFE_FREE(udp);
 450                 return NULL;
 451         }
 452
 453         udp->PAM_username = user;
 454         udp->PAM_password = passwd;
 455         udp->PAM_newpassword = newpass;
 456
 457         pconv->conv = smb_pam_conv_fnptr;
 458         pconv->appdata_ptr = (void *)udp;
 459         return pconv;
 460 }
 461
 462 /*
 463  * PAM Closing out cleanup handler
 464  */
 465
 466 static bool smb_pam_end(pam_handle_t *pamh, struct pam_conv *smb_pam_conv_ptr)
 467 {
 468         int pam_error;
 469
 470         smb_free_pam_conv(smb_pam_conv_ptr);
 471
 472         if( pamh != NULL ) {
 473                 pam_error = pam_end(pamh, 0);
 474                 if (pam_error == PAM_SUCCESS) {
 475                         DBG_NOTICE("PAM: PAM_END OK.\n");
 476                         return True;
 477                 }
 478
 479                 DBG_WARNING("PAM: PAM_END FAILED (%d).\n", pam_error);
 480         } else {
 481                 DBG_INFO("PAM: not initialised\n");
 482         }
 483
 484         return False;
 485 }
 486
 487 /*
 488  * Start PAM authentication for specified account
 489  */
 490
 491 static bool smb_pam_start(pam_handle_t **pamh, const char *user, const char *rhost, struct pam_conv *pconv)
 492 {
 493         int pam_error;
 494
 495         *pamh = (pam_handle_t *)NULL;
 496
 497         DEBUG(4,("smb_pam_start: PAM: Init user: %s\n", user));
 498
 499         pam_error = pam_start("samba", user, pconv, pamh);
 500         if( !smb_pam_error_handler(*pamh, pam_error, "Init Failed", 0)) {
 501                 *pamh = (pam_handle_t *)NULL;
 502                 return False;
 503         }
 504
 505 #ifdef HAVE_PAM_RHOST
 506         DEBUG(4,("smb_pam_start: PAM: setting rhost to: %s\n", rhost));
 507         pam_error = pam_set_item(*pamh, PAM_RHOST, rhost);
 508         if(!smb_pam_error_handler(*pamh, pam_error, "set rhost failed", 0)) {
 509                 smb_pam_end(*pamh, pconv);
 510                 *pamh = (pam_handle_t *)NULL;
 511                 return False;
 512         }
 513 #endif
 514 #ifdef HAVE_PAM_TTY
 515         DEBUG(4,("smb_pam_start: PAM: setting tty\n"));
 516         pam_error = pam_set_item(*pamh, PAM_TTY, "samba");
 517         if (!smb_pam_error_handler(*pamh, pam_error, "set tty failed", 0)) {
 518                 smb_pam_end(*pamh, pconv);
 519                 *pamh = (pam_handle_t *)NULL;
 520                 return False;
 521         }
 522 #endif
 523         DEBUG(4,("smb_pam_start: PAM: Init passed for user: %s\n", user));
 524         return True;
 525 }
 526
 527 /*
 528  * PAM Authentication Handler
 529  */
 530 static NTSTATUS smb_pam_auth(pam_handle_t *pamh, const char *user)
 531 {
 532         int pam_error;
 533         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 534
 535         /*
 536          * To enable debugging set in /etc/pam.d/samba:
 537          *      auth required /lib/security/pam_pwdb.so nullok shadow audit
 538          */
 539
 540         DEBUG(4,("smb_pam_auth: PAM: Authenticate User: %s\n", user));
 541         pam_error = pam_authenticate(pamh, PAM_SILENT | (lp_null_passwords() ? 0 : PAM_DISALLOW_NULL_AUTHTOK));
 542         switch( pam_error ){
 543                 case PAM_AUTH_ERR:
 544                         DEBUG(2, ("smb_pam_auth: PAM: Authentication Error for user %s\n", user));
 545                         break;
 546                 case PAM_CRED_INSUFFICIENT:
 547                         DEBUG(2, ("smb_pam_auth: PAM: Insufficient Credentials for user %s\n", user));
 548                         break;
 549                 case PAM_AUTHINFO_UNAVAIL:
 550                         DEBUG(2, ("smb_pam_auth: PAM: Authentication Information Unavailable for user %s\n", user));
 551                         break;
 552                 case PAM_USER_UNKNOWN:
 553                         DEBUG(2, ("smb_pam_auth: PAM: Username %s NOT known to Authentication system\n", user));
 554                         break;
 555                 case PAM_MAXTRIES:
 556                         DEBUG(2, ("smb_pam_auth: PAM: One or more authentication modules reports user limit for user %s exceeeded\n", user));
 557                         break;
 558                 case PAM_ABORT:
 559                         DEBUG(0, ("smb_pam_auth: PAM: One or more PAM modules failed to load for user %s\n", user));
 560                         break;
 561                 case PAM_SUCCESS:
 562                         DEBUG(4, ("smb_pam_auth: PAM: User %s Authenticated OK\n", user));
 563                         break;
 564                 default:
 565                         DEBUG(0, ("smb_pam_auth: PAM: UNKNOWN ERROR while authenticating user %s\n", user));
 566                         break;
 567         }
 568
 569         smb_pam_nt_status_error_handler(pamh, pam_error, "Authentication Failure", 2, &nt_status);
 570         return nt_status;
 571 }
 572
 573 /*
 574  * PAM Account Handler
 575  */
 576 static NTSTATUS smb_pam_account(pam_handle_t *pamh, const char * user)
 577 {
 578         int pam_error;
 579         NTSTATUS nt_status = NT_STATUS_ACCOUNT_DISABLED;
 580
 581         DEBUG(4,("smb_pam_account: PAM: Account Management for User: %s\n", user));
 582         pam_error = pam_acct_mgmt(pamh, PAM_SILENT); /* Is user account enabled? */
 583         switch( pam_error ) {
 584                 case PAM_AUTHTOK_EXPIRED:
 585                         DEBUG(2, ("smb_pam_account: PAM: User %s is valid but password is expired\n", user));
 586                         break;
 587                 case PAM_ACCT_EXPIRED:
 588                         DEBUG(2, ("smb_pam_account: PAM: User %s no longer permitted to access system\n", user));
 589                         break;
 590                 case PAM_AUTH_ERR:
 591                         DEBUG(2, ("smb_pam_account: PAM: There was an authentication error for user %s\n", user));
 592                         break;
 593                 case PAM_PERM_DENIED:
 594                         DEBUG(0, ("smb_pam_account: PAM: User %s is NOT permitted to access system at this time\n", user));
 595                         break;
 596                 case PAM_USER_UNKNOWN:
 597                         DEBUG(0, ("smb_pam_account: PAM: User \"%s\" is NOT known to account management\n", user));
 598                         break;
 599                 case PAM_SUCCESS:
 600                         DEBUG(4, ("smb_pam_account: PAM: Account OK for User: %s\n", user));
 601                         break;
 602                 default:
 603                         DEBUG(0, ("smb_pam_account: PAM: UNKNOWN PAM ERROR (%d) during Account Management for User: %s\n", pam_error, user));
 604                         break;
 605         }
 606
 607         smb_pam_nt_status_error_handler(pamh, pam_error, "Account Check Failed", 2, &nt_status);
 608         return nt_status;
 609 }
 610
 611 /*
 612  * PAM Credential Setting
 613  */
 614
 615 static NTSTATUS smb_pam_setcred(pam_handle_t *pamh, const char * user)
 616 {
 617         int pam_error;
 618         NTSTATUS nt_status = NT_STATUS_NO_TOKEN;
 619
 620         /*
 621          * This will allow samba to acquire a kerberos token. And, when
 622          * exporting an AFS cell, be able to /write/ to this cell.
 623          */
 624
 625         DEBUG(4,("PAM: Account Management SetCredentials for User: %s\n", user));
 626         pam_error = pam_setcred(pamh, (PAM_ESTABLISH_CRED|PAM_SILENT));
 627         switch( pam_error ) {
 628                 case PAM_CRED_UNAVAIL:
 629                         DEBUG(0, ("smb_pam_setcred: PAM: Credentials not found for user:%s\n", user ));
 630                         break;
 631                 case PAM_CRED_EXPIRED:
 632                         DEBUG(0, ("smb_pam_setcred: PAM: Credentials for user: \"%s\" EXPIRED!\n", user ));
 633                         break;
 634                 case PAM_USER_UNKNOWN:
 635                         DEBUG(0, ("smb_pam_setcred: PAM: User: \"%s\" is NOT known so can not set credentials!\n", user ));
 636                         break;
 637                 case PAM_CRED_ERR:
 638                         DEBUG(0, ("smb_pam_setcred: PAM: Unknown setcredentials error - unable to set credentials for %s\n", user ));
 639                         break;
 640                 case PAM_SUCCESS:
 641                         DEBUG(4, ("smb_pam_setcred: PAM: SetCredentials OK for User: %s\n", user));
 642                         break;
 643                 default:
 644                         DEBUG(0, ("smb_pam_setcred: PAM: UNKNOWN PAM ERROR (%d) during SetCredentials for User: %s\n", pam_error, user));
 645                         break;
 646         }
 647
 648         smb_pam_nt_status_error_handler(pamh, pam_error, "Set Credential Failure", 2, &nt_status);
 649         return nt_status;
 650 }
 651
 652 /*
 653  * PAM Internal Session Handler
 654  */
 655 static bool smb_internal_pam_session(pam_handle_t *pamh, const char *user, const char *tty, bool flag)
 656 {
 657         int pam_error;
 658
 659 #ifdef HAVE_PAM_TTY
 660         DEBUG(4,("smb_internal_pam_session: PAM: tty set to: %s\n", tty));
 661         pam_error = pam_set_item(pamh, PAM_TTY, tty);
 662         if (!smb_pam_error_handler(pamh, pam_error, "set tty failed", 0))
 663                 return False;
 664 #endif
 665
 666         if (flag) {
 667                 pam_error = pam_open_session(pamh, PAM_SILENT);
 668                 if (!smb_pam_error_handler(pamh, pam_error, "session setup failed", 0))
 669                         return False;
 670         } else {
 671                 pam_setcred(pamh, (PAM_DELETE_CRED|PAM_SILENT)); /* We don't care if this fails */
 672                 pam_error = pam_close_session(pamh, PAM_SILENT); /* This will probably pick up the error anyway */
 673                 if (!smb_pam_error_handler(pamh, pam_error, "session close failed", 0))
 674                         return False;
 675         }
 676         return (True);
 677 }
 678
 679 /*
 680  * Internal PAM Password Changer.
 681  */
 682
 683 static bool smb_pam_chauthtok(pam_handle_t *pamh, const char * user)
 684 {
 685         int pam_error;
 686
 687         DEBUG(4,("smb_pam_chauthtok: PAM: Password Change for User: %s\n", user));
 688
 689         pam_error = pam_chauthtok(pamh, PAM_SILENT); /* Change Password */
 690
 691         switch( pam_error ) {
 692         case PAM_AUTHTOK_ERR:
 693                 DEBUG(2, ("PAM: unable to obtain the new authentication token - is password to weak?\n"));
 694                 break;
 695
 696         /* This doesn't seem to be defined on Solaris. JRA */
 697 #ifdef PAM_AUTHTOK_RECOVER_ERR
 698         case PAM_AUTHTOK_RECOVER_ERR:
 699                 DEBUG(2, ("PAM: unable to obtain the old authentication token - was the old password wrong?.\n"));
 700                 break;
 701 #endif
 702
 703         case PAM_AUTHTOK_LOCK_BUSY:
 704                 DEBUG(2, ("PAM: unable to change the authentication token since it is currently locked.\n"));
 705                 break;
 706         case PAM_AUTHTOK_DISABLE_AGING:
 707                 DEBUG(2, ("PAM: Authentication token aging has been disabled.\n"));
 708                 break;
 709         case PAM_PERM_DENIED:
 710                 DEBUG(0, ("PAM: Permission denied.\n"));
 711                 break;
 712         case PAM_TRY_AGAIN:
 713                 DEBUG(0, ("PAM: Could not update all authentication token(s). No authentication tokens were updated.\n"));
 714                 break;
 715         case PAM_USER_UNKNOWN:
 716                 DEBUG(0, ("PAM: User not known to PAM\n"));
 717                 break;
 718         case PAM_SUCCESS:
 719                 DEBUG(4, ("PAM: Account OK for User: %s\n", user));
 720                 break;
 721         default:
 722                 DEBUG(0, ("PAM: UNKNOWN PAM ERROR (%d) for User: %s\n", pam_error, user));
 723         }
 724
 725         if(!smb_pam_error_handler(pamh, pam_error, "Password Change Failed", 2)) {
 726                 return False;
 727         }
 728
 729         /* If this point is reached, the password has changed. */
 730         return True;
 731 }
 732
 733 /*
 734  * PAM Externally accessible Session handler
 735  */
 736
 737 bool smb_pam_claim_session(const char *user, const char *tty, const char *rhost)
 738 {
 739         pam_handle_t *pamh = NULL;
 740         struct pam_conv *pconv = NULL;
 741
 742         /* Ignore PAM if told to. */
 743
 744         if (!lp_obey_pam_restrictions())
 745                 return True;
 746
 747         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
 748                 return False;
 749
 750         if (!smb_pam_start(&pamh, user, rhost, pconv))
 751                 return False;
 752
 753         if (!smb_internal_pam_session(pamh, user, tty, True)) {
 754                 smb_pam_end(pamh, pconv);
 755                 return False;
 756         }
 757
 758         return smb_pam_end(pamh, pconv);
 759 }
 760
 761 /*
 762  * PAM Externally accessible Session handler
 763  */
 764
 765 bool smb_pam_close_session(const char *user, const char *tty, const char *rhost)
 766 {
 767         pam_handle_t *pamh = NULL;
 768         struct pam_conv *pconv = NULL;
 769
 770         /* Ignore PAM if told to. */
 771
 772         if (!lp_obey_pam_restrictions())
 773                 return True;
 774
 775         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
 776                 return False;
 777
 778         if (!smb_pam_start(&pamh, user, rhost, pconv))
 779                 return False;
 780
 781         if (!smb_internal_pam_session(pamh, user, tty, False)) {
 782                 smb_pam_end(pamh, pconv);
 783                 return False;
 784         }
 785
 786         return smb_pam_end(pamh, pconv);
 787 }
 788
 789 /*
 790  * PAM Externally accessible Account handler
 791  */
 792
 793 NTSTATUS smb_pam_accountcheck(const char *user, const char *rhost)
 794 {
 795         NTSTATUS nt_status = NT_STATUS_ACCOUNT_DISABLED;
 796         pam_handle_t *pamh = NULL;
 797         struct pam_conv *pconv = NULL;
 798
 799         /* Ignore PAM if told to. */
 800
 801         if (!lp_obey_pam_restrictions())
 802                 return NT_STATUS_OK;
 803
 804         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
 805                 return NT_STATUS_NO_MEMORY;
 806
 807         if (!smb_pam_start(&pamh, user, rhost, pconv))
 808                 return NT_STATUS_ACCOUNT_DISABLED;
 809
 810         if (!NT_STATUS_IS_OK(nt_status = smb_pam_account(pamh, user)))
 811                 DEBUG(0, ("smb_pam_accountcheck: PAM: Account Validation Failed - Rejecting User %s!\n", user));
 812
 813         smb_pam_end(pamh, pconv);
 814         return nt_status;
 815 }
 816
 817 /*
 818  * PAM Password Validation Suite
 819  */
 820
 821 NTSTATUS smb_pam_passcheck(const char * user, const char * rhost,
 822                            const char * password)
 823 {
 824         pam_handle_t *pamh = NULL;
 825         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 826         struct pam_conv *pconv = NULL;
 827
 828         /*
 829          * Note we can't ignore PAM here as this is the only
 830          * way of doing auths on plaintext passwords when
 831          * compiled --with-pam.
 832          */
 833
 834         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, password, NULL)) == NULL)
 835                 return NT_STATUS_LOGON_FAILURE;
 836
 837         if (!smb_pam_start(&pamh, user, rhost, pconv))
 838                 return NT_STATUS_LOGON_FAILURE;
 839
 840         if (!NT_STATUS_IS_OK(nt_status = smb_pam_auth(pamh, user))) {
 841                 DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_auth failed - Rejecting User %s !\n", user));
 842                 smb_pam_end(pamh, pconv);
 843                 return nt_status;
 844         }
 845
 846         if (!NT_STATUS_IS_OK(nt_status = smb_pam_account(pamh, user))) {
 847                 DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_account failed - Rejecting User %s !\n", user));
 848                 smb_pam_end(pamh, pconv);
 849                 return nt_status;
 850         }
 851
 852         if (!NT_STATUS_IS_OK(nt_status = smb_pam_setcred(pamh, user))) {
 853                 DEBUG(0, ("smb_pam_passcheck: PAM: smb_pam_setcred failed - Rejecting User %s !\n", user));
 854                 smb_pam_end(pamh, pconv);
 855                 return nt_status;
 856         }
 857
 858         smb_pam_end(pamh, pconv);
 859         return nt_status;
 860 }
 861
 862 /*
 863  * PAM Password Change Suite
 864  */
 865
 866 bool smb_pam_passchange(const char *user, const char *rhost,
 867                         const char *oldpassword, const char *newpassword)
 868 {
 869         /* Appropriate quantities of root should be obtained BEFORE calling this function */
 870         struct pam_conv *pconv = NULL;
 871         pam_handle_t *pamh = NULL;
 872
 873         if ((pconv = smb_setup_pam_conv(smb_pam_passchange_conv, user, oldpassword, newpassword)) == NULL)
 874                 return False;
 875
 876         if(!smb_pam_start(&pamh, user, rhost, pconv))
 877                 return False;
 878
 879         if (!smb_pam_chauthtok(pamh, user)) {
 880                 DEBUG(0, ("smb_pam_passchange: PAM: Password Change Failed for user %s!\n", user));
 881                 smb_pam_end(pamh, pconv);
 882                 return False;
 883         }
 884
 885         return smb_pam_end(pamh, pconv);
 886 }
 887
 888 #else
 889
 890 /* If PAM not used, no PAM restrictions on accounts. */
 891 NTSTATUS smb_pam_accountcheck(const char *user, const char *rhost)
 892 {
 893         return NT_STATUS_OK;
 894 }
 895
 896 /* If PAM not used, also no PAM restrictions on sessions. */
 897 bool smb_pam_claim_session(const char *user, const char *tty, const char *rhost)
 898 {
 899         return True;
 900 }
 901
 902 /* If PAM not used, also no PAM restrictions on sessions. */
 903 bool smb_pam_close_session(const char *in_user, const char *tty, const char *rhost)
 904 {
 905         return True;
 906 }
 907 #endif /* WITH_PAM */