source3/nsswitch/pam_winbind.c

   1 /* pam_winbind module
   2
   3    Copyright Andrew Tridgell <tridge@samba.org> 2000
   4    Copyright Tim Potter <tpot@samba.org> 2000
   5    Copyright Andrew Bartlett <abartlet@samba.org> 2002
   6
   7    largely based on pam_userdb by Christian Gafton <gafton@redhat.com>
   8    also contains large slabs of code from pam_unix by Elliot Lee <sopwith@redhat.com>
   9    (see copyright below for full details)
  10 */
  11
  12 #include "pam_winbind.h"
  13
  14 /* data tokens */
  15
  16 #define MAX_PASSWD_TRIES        3
  17
  18 /* some syslogging */
  19 static void _pam_log(int err, const char *format, ...)
  20 {
  21         va_list args;
  22
  23         va_start(args, format);
  24         openlog(MODULE_NAME, LOG_CONS|LOG_PID, LOG_AUTH);
  25         vsyslog(err, format, args);
  26         va_end(args);
  27         closelog();
  28 }
  29
  30 static int _pam_parse(int argc, const char **argv)
  31 {
  32         int ctrl;
  33         /* step through arguments */
  34         for (ctrl = 0; argc-- > 0; ++argv) {
  35
  36                 /* generic options */
  37
  38                 if (!strcmp(*argv,"debug"))
  39                         ctrl |= WINBIND_DEBUG_ARG;
  40                 else if (!strcasecmp(*argv, "use_authtok"))
  41                         ctrl |= WINBIND_USE_AUTHTOK_ARG;
  42                 else if (!strcasecmp(*argv, "use_first_pass"))
  43                         ctrl |= WINBIND_USE_FIRST_PASS_ARG;
  44                 else if (!strcasecmp(*argv, "try_first_pass"))
  45                         ctrl |= WINBIND_TRY_FIRST_PASS_ARG;
  46                 else if (!strcasecmp(*argv, "unknown_ok"))
  47                         ctrl |= WINBIND_UNKNOWN_OK_ARG;
  48                 else {
  49                         _pam_log(LOG_ERR, "pam_parse: unknown option; %s", *argv);
  50                 }
  51         }
  52
  53         return ctrl;
  54 }
  55
  56 /* --- authentication management functions --- */
  57
  58 /* Attempt a conversation */
  59
  60 static int converse(pam_handle_t *pamh, int nargs,
  61                     struct pam_message **message,
  62                     struct pam_response **response)
  63 {
  64     int retval;
  65     struct pam_conv *conv;
  66
  67     retval = pam_get_item(pamh, PAM_CONV, (const void **) &conv ) ;
  68     if (retval == PAM_SUCCESS) {
  69         retval = conv->conv(nargs, (const struct pam_message **)message,
  70                             response, conv->appdata_ptr);
  71     }
  72
  73     return retval; /* propagate error status */
  74 }
  75
  76
  77 static int _make_remark(pam_handle_t * pamh, int type, const char *text)
  78 {
  79         int retval = PAM_SUCCESS;
  80
  81         struct pam_message *pmsg[1], msg[1];
  82         struct pam_response *resp;
  83
  84         pmsg[0] = &msg[0];
  85         msg[0].msg = text;
  86         msg[0].msg_style = type;
  87
  88         resp = NULL;
  89         retval = converse(pamh, 1, pmsg, &resp);
  90
  91         if (resp) {
  92                 _pam_drop_reply(resp, 1);
  93         }
  94         return retval;
  95 }
  96
  97 static int pam_winbind_request(enum winbindd_cmd req_type,
  98                                struct winbindd_request *request,
  99                                struct winbindd_response *response)
 100 {
 101
 102         /* Fill in request and send down pipe */
 103         init_request(request, req_type);
 104
 105         if (write_sock(request, sizeof(*request)) == -1) {
 106                 _pam_log(LOG_ERR, "write to socket failed!");
 107                 close_sock();
 108                 return PAM_SERVICE_ERR;
 109         }
 110
 111         /* Wait for reply */
 112         if (read_reply(response) == -1) {
 113                 _pam_log(LOG_ERR, "read from socket failed!");
 114                 close_sock();
 115                 return PAM_SERVICE_ERR;
 116         }
 117
 118         /* We are done with the socket - close it and avoid mischeif */
 119         close_sock();
 120
 121         /* Copy reply data from socket */
 122         if (response->result != WINBINDD_OK) {
 123                 if (response->data.auth.pam_error != PAM_SUCCESS) {
 124                         _pam_log(LOG_ERR, "request failed, PAM error was %d, NT error was %s",
 125                                  response->data.auth.pam_error,
 126                                  response->data.auth.nt_status_string);
 127                         return response->data.auth.pam_error;
 128                 } else {
 129                         _pam_log(LOG_ERR, "request failed, but PAM error 0!");
 130                         return PAM_SERVICE_ERR;
 131                 }
 132         }
 133
 134         return PAM_SUCCESS;
 135 }
 136
 137 static int pam_winbind_request_log(enum winbindd_cmd req_type,
 138                                struct winbindd_request *request,
 139                                struct winbindd_response *response,
 140                                    int ctrl,
 141                                    const char *user)
 142 {
 143         int retval;
 144
 145         retval = pam_winbind_request(req_type, request, response);
 146
 147         switch (retval) {
 148         case PAM_AUTH_ERR:
 149                 /* incorrect password */
 150                 _pam_log(LOG_WARNING, "user `%s' denied access (incorrect password)", user);
 151                 return retval;
 152         case PAM_ACCT_EXPIRED:
 153                 /* account expired */
 154                 _pam_log(LOG_WARNING, "user `%s' account expired", user);
 155                 return retval;
 156         case PAM_AUTHTOK_EXPIRED:
 157                 /* password expired */
 158                 _pam_log(LOG_WARNING, "user `%s' password expired", user);
 159                 return retval;
 160         case PAM_NEW_AUTHTOK_REQD:
 161                 /* password expired */
 162                 _pam_log(LOG_WARNING, "user `%s' new password required", user);
 163                 return retval;
 164         case PAM_USER_UNKNOWN:
 165                 /* the user does not exist */
 166                 if (ctrl & WINBIND_DEBUG_ARG)
 167                         _pam_log(LOG_NOTICE, "user `%s' not found",
 168                                  user);
 169                 if (ctrl & WINBIND_UNKNOWN_OK_ARG) {
 170                         return PAM_IGNORE;
 171                 }
 172                 return retval;
 173         case PAM_SUCCESS:
 174                 if (req_type == WINBINDD_PAM_AUTH) {
 175                         /* Otherwise, the authentication looked good */
 176                         _pam_log(LOG_NOTICE, "user '%s' granted acces", user);
 177                 } else if (req_type == WINBINDD_PAM_CHAUTHTOK) {
 178                         /* Otherwise, the authentication looked good */
 179                         _pam_log(LOG_NOTICE, "user '%s' password changed", user);
 180                 } else {
 181                         /* Otherwise, the authentication looked good */
 182                         _pam_log(LOG_NOTICE, "user '%s' OK", user);
 183                 }
 184                 return retval;
 185         default:
 186                 /* we don't know anything about this return value */
 187                 _pam_log(LOG_ERR, "internal module error (retval = %d, user = `%s'",
 188                          retval, user);
 189                 return retval;
 190         }
 191 }
 192
 193 /* talk to winbindd */
 194 static int winbind_auth_request(const char *user, const char *pass, int ctrl)
 195 {
 196         struct winbindd_request request;
 197         struct winbindd_response response;
 198
 199         ZERO_STRUCT(request);
 200
 201         strncpy(request.data.auth.user, user,
 202                 sizeof(request.data.auth.user)-1);
 203
 204         strncpy(request.data.auth.pass, pass,
 205                 sizeof(request.data.auth.pass)-1);
 206
 207
 208         return pam_winbind_request_log(WINBINDD_PAM_AUTH, &request, &response, ctrl, user);
 209 }
 210
 211 /* talk to winbindd */
 212 static int winbind_chauthtok_request(const char *user, const char *oldpass,
 213                                      const char *newpass, int ctrl)
 214 {
 215         struct winbindd_request request;
 216         struct winbindd_response response;
 217
 218         ZERO_STRUCT(request);
 219
 220         if (request.data.chauthtok.user == NULL) return -2;
 221
 222         strncpy(request.data.chauthtok.user, user,
 223                 sizeof(request.data.chauthtok.user) - 1);
 224
 225         if (oldpass != NULL) {
 226             strncpy(request.data.chauthtok.oldpass, oldpass,
 227                     sizeof(request.data.chauthtok.oldpass) - 1);
 228         } else {
 229             request.data.chauthtok.oldpass[0] = '\0';
 230         }
 231
 232         if (newpass != NULL) {
 233             strncpy(request.data.chauthtok.newpass, newpass,
 234                     sizeof(request.data.chauthtok.newpass) - 1);
 235         } else {
 236             request.data.chauthtok.newpass[0] = '\0';
 237         }
 238
 239         return pam_winbind_request_log(WINBINDD_PAM_CHAUTHTOK, &request, &response, ctrl, user);
 240 }
 241
 242 /*
 243  * Checks if a user has an account
 244  *
 245  * return values:
 246  *       1  = User not found
 247  *       0  = OK
 248  *      -1  = System error
 249  */
 250 static int valid_user(const char *user)
 251 {
 252         if (getpwnam(user)) return 0;
 253         return 1;
 254 }
 255
 256 static char *_pam_delete(register char *xx)
 257 {
 258     _pam_overwrite(xx);
 259     _pam_drop(xx);
 260     return NULL;
 261 }
 262
 263 /*
 264  * obtain a password from the user
 265  */
 266
 267 static int _winbind_read_password(pam_handle_t * pamh
 268                                   ,unsigned int ctrl
 269                                   ,const char *comment
 270                                   ,const char *prompt1
 271                                   ,const char *prompt2
 272                                   ,const char **pass)
 273 {
 274         int authtok_flag;
 275         int retval;
 276         const char *item;
 277         char *token;
 278
 279         /*
 280          * make sure nothing inappropriate gets returned
 281          */
 282
 283         *pass = token = NULL;
 284
 285         /*
 286          * which authentication token are we getting?
 287          */
 288
 289         authtok_flag = on(WINBIND__OLD_PASSWORD, ctrl) ? PAM_OLDAUTHTOK : PAM_AUTHTOK;
 290
 291         /*
 292          * should we obtain the password from a PAM item ?
 293          */
 294
 295         if (on(WINBIND_TRY_FIRST_PASS_ARG, ctrl) || on(WINBIND_USE_FIRST_PASS_ARG, ctrl)) {
 296                 retval = pam_get_item(pamh, authtok_flag, (const void **) &item);
 297                 if (retval != PAM_SUCCESS) {
 298                         /* very strange. */
 299                         _pam_log(LOG_ALERT,
 300                                  "pam_get_item returned error to unix-read-password"
 301                             );
 302                         return retval;
 303                 } else if (item != NULL) {      /* we have a password! */
 304                         *pass = item;
 305                         item = NULL;
 306                         return PAM_SUCCESS;
 307                 } else if (on(WINBIND_USE_FIRST_PASS_ARG, ctrl)) {
 308                         return PAM_AUTHTOK_RECOVER_ERR;         /* didn't work */
 309                 } else if (on(WINBIND_USE_AUTHTOK_ARG, ctrl)
 310                            && off(WINBIND__OLD_PASSWORD, ctrl)) {
 311                         return PAM_AUTHTOK_RECOVER_ERR;
 312                 }
 313         }
 314         /*
 315          * getting here implies we will have to get the password from the
 316          * user directly.
 317          */
 318
 319         {
 320                 struct pam_message msg[3], *pmsg[3];
 321                 struct pam_response *resp;
 322                 int i, replies;
 323
 324                 /* prepare to converse */
 325
 326                 if (comment != NULL) {
 327                         pmsg[0] = &msg[0];
 328                         msg[0].msg_style = PAM_TEXT_INFO;
 329                         msg[0].msg = comment;
 330                         i = 1;
 331                 } else {
 332                         i = 0;
 333                 }
 334
 335                 pmsg[i] = &msg[i];
 336                 msg[i].msg_style = PAM_PROMPT_ECHO_OFF;
 337                 msg[i++].msg = prompt1;
 338                 replies = 1;
 339
 340                 if (prompt2 != NULL) {
 341                         pmsg[i] = &msg[i];
 342                         msg[i].msg_style = PAM_PROMPT_ECHO_OFF;
 343                         msg[i++].msg = prompt2;
 344                         ++replies;
 345                 }
 346                 /* so call the conversation expecting i responses */
 347                 resp = NULL;
 348                 retval = converse(pamh, i, pmsg, &resp);
 349
 350                 if (resp != NULL) {
 351
 352                         /* interpret the response */
 353
 354                         if (retval == PAM_SUCCESS) {    /* a good conversation */
 355
 356                                 token = x_strdup(resp[i - replies].resp);
 357                                 if (token != NULL) {
 358                                         if (replies == 2) {
 359
 360                                                 /* verify that password entered correctly */
 361                                                 if (!resp[i - 1].resp
 362                                                     || strcmp(token, resp[i - 1].resp)) {
 363                                                         _pam_delete(token);     /* mistyped */
 364                                                         retval = PAM_AUTHTOK_RECOVER_ERR;
 365                                                         _make_remark(pamh                                                                   ,PAM_ERROR_MSG, MISTYPED_PASS);
 366                                                 }
 367                                         }
 368                                 } else {
 369                                         _pam_log(LOG_NOTICE
 370                                                  ,"could not recover authentication token");
 371                                 }
 372
 373                         }
 374                         /*
 375                          * tidy up the conversation (resp_retcode) is ignored
 376                          * -- what is it for anyway? AGM
 377                          */
 378
 379                         _pam_drop_reply(resp, i);
 380
 381                 } else {
 382                         retval = (retval == PAM_SUCCESS)
 383                             ? PAM_AUTHTOK_RECOVER_ERR : retval;
 384                 }
 385         }
 386
 387         if (retval != PAM_SUCCESS) {
 388                 if (on(WINBIND_DEBUG_ARG, ctrl))
 389                         _pam_log(LOG_DEBUG,
 390                                  "unable to obtain a password");
 391                 return retval;
 392         }
 393         /* 'token' is the entered password */
 394
 395         /* we store this password as an item */
 396
 397         retval = pam_set_item(pamh, authtok_flag, token);
 398         _pam_delete(token);     /* clean it up */
 399         if (retval != PAM_SUCCESS
 400             || (retval = pam_get_item(pamh, authtok_flag
 401                                       ,(const void **) &item))
 402             != PAM_SUCCESS) {
 403
 404                 _pam_log(LOG_CRIT, "error manipulating password");
 405                 return retval;
 406
 407         }
 408
 409         *pass = item;
 410         item = NULL;            /* break link to password */
 411
 412         return PAM_SUCCESS;
 413 }
 414
 415 PAM_EXTERN
 416 int pam_sm_authenticate(pam_handle_t *pamh, int flags,
 417                         int argc, const char **argv)
 418 {
 419      const char *username;
 420      const char *password;
 421      int retval = PAM_AUTH_ERR;
 422
 423      /* parse arguments */
 424      int ctrl = _pam_parse(argc, argv);
 425
 426      /* Get the username */
 427      retval = pam_get_user(pamh, &username, NULL);
 428      if ((retval != PAM_SUCCESS) || (!username)) {
 429         if (ctrl & WINBIND_DEBUG_ARG)
 430             _pam_log(LOG_DEBUG,"can not get the username");
 431         return PAM_SERVICE_ERR;
 432      }
 433
 434      retval = _winbind_read_password(pamh, ctrl, NULL,
 435                                      "Password: ", NULL,
 436                                      &password);
 437
 438      if (retval != PAM_SUCCESS) {
 439          _pam_log(LOG_ERR, "Could not retrieve user's password");
 440          return PAM_AUTHTOK_ERR;
 441      }
 442
 443      if (ctrl & WINBIND_DEBUG_ARG) {
 444
 445              /* Let's not give too much away in the log file */
 446
 447 #ifdef DEBUG_PASSWORD
 448          _pam_log(LOG_INFO, "Verify user `%s' with password `%s'",
 449                   username, password);
 450 #else
 451          _pam_log(LOG_INFO, "Verify user `%s'", username);
 452 #endif
 453      }
 454
 455      /* Now use the username to look up password */
 456      return winbind_auth_request(username, password, ctrl);
 457 }
 458
 459 PAM_EXTERN
 460 int pam_sm_setcred(pam_handle_t *pamh, int flags,
 461                    int argc, const char **argv)
 462 {
 463     return PAM_SUCCESS;
 464 }
 465
 466 /*
 467  * Account management. We want to verify that the account exists
 468  * before returning PAM_SUCCESS
 469  */
 470 PAM_EXTERN
 471 int pam_sm_acct_mgmt(pam_handle_t *pamh, int flags,
 472                    int argc, const char **argv)
 473 {
 474     const char *username;
 475     int retval = PAM_USER_UNKNOWN;
 476
 477     /* parse arguments */
 478     int ctrl = _pam_parse(argc, argv);
 479
 480     /* Get the username */
 481     retval = pam_get_user(pamh, &username, NULL);
 482     if ((retval != PAM_SUCCESS) || (!username)) {
 483         if (ctrl & WINBIND_DEBUG_ARG)
 484             _pam_log(LOG_DEBUG,"can not get the username");
 485         return PAM_SERVICE_ERR;
 486     }
 487
 488     /* Verify the username */
 489     retval = valid_user(username);
 490     switch (retval) {
 491         case -1:
 492             /* some sort of system error. The log was already printed */
 493             return PAM_SERVICE_ERR;
 494         case 1:
 495             /* the user does not exist */
 496             if (ctrl & WINBIND_DEBUG_ARG)
 497                 _pam_log(LOG_NOTICE, "user `%s' not found",
 498                          username);
 499             if (ctrl & WINBIND_UNKNOWN_OK_ARG)
 500                 return PAM_IGNORE;
 501             return PAM_USER_UNKNOWN;
 502         case 0:
 503             /* Otherwise, the authentication looked good */
 504             _pam_log(LOG_NOTICE, "user '%s' granted acces", username);
 505             return PAM_SUCCESS;
 506         default:
 507             /* we don't know anything about this return value */
 508             _pam_log(LOG_ERR, "internal module error (retval = %d, user = `%s'",
 509                      retval, username);
 510             return PAM_SERVICE_ERR;
 511     }
 512
 513     /* should not be reached */
 514     return PAM_IGNORE;
 515 }
 516 PAM_EXTERN
 517 int pam_sm_open_session(pam_handle_t *pamh, int flags,
 518                 int argc, const char **argv)
 519 {
 520         /* parse arguments */
 521         int ctrl = _pam_parse(argc, argv);
 522         if (ctrl & WINBIND_DEBUG_ARG)
 523               _pam_log(LOG_DEBUG,"libpam_winbind:pam_sm_open_session handler");
 524         return PAM_SUCCESS;
 525 }
 526 PAM_EXTERN
 527 int pam_sm_close_session(pam_handle_t *pamh, int flags,
 528                 int argc, const char **argv)
 529 {
 530         /* parse arguments */
 531         int ctrl = _pam_parse(argc, argv);
 532         if (ctrl & WINBIND_DEBUG_ARG)
 533               _pam_log(LOG_DEBUG,"libpam_winbind:pam_sm_close_session handler");
 534         return PAM_SUCCESS;
 535 }
 536
 537
 538
 539 PAM_EXTERN int pam_sm_chauthtok(pam_handle_t * pamh, int flags,
 540                                 int argc, const char **argv)
 541 {
 542         unsigned int lctrl;
 543         int retval;
 544         unsigned int ctrl = _pam_parse(argc, argv);
 545
 546         /* <DO NOT free() THESE> */
 547         const char *user;
 548         char *pass_old, *pass_new;
 549         /* </DO NOT free() THESE> */
 550
 551         char *Announce;
 552
 553         int retry = 0;
 554
 555         /*
 556          * First get the name of a user
 557          */
 558         retval = pam_get_user(pamh, &user, "Username: ");
 559         if (retval == PAM_SUCCESS) {
 560                 if (user == NULL) {
 561                         _pam_log(LOG_ERR, "username was NULL!");
 562                         return PAM_USER_UNKNOWN;
 563                 }
 564                 if (retval == PAM_SUCCESS && on(WINBIND_DEBUG_ARG, ctrl))
 565                         _pam_log(LOG_DEBUG, "username [%s] obtained",
 566                                  user);
 567         } else {
 568                 if (on(WINBIND_DEBUG_ARG, ctrl))
 569                         _pam_log(LOG_DEBUG,
 570                                  "password - could not identify user");
 571                 return retval;
 572         }
 573
 574         /*
 575          * obtain and verify the current password (OLDAUTHTOK) for
 576          * the user.
 577          */
 578
 579         if (flags & PAM_PRELIM_CHECK) {
 580
 581                 /* instruct user what is happening */
 582 #define greeting "Changing password for "
 583                 Announce = (char *) malloc(sizeof(greeting) + strlen(user));
 584                 if (Announce == NULL) {
 585                 _pam_log(LOG_CRIT,
 586                          "password - out of memory");
 587                 return PAM_BUF_ERR;
 588                 }
 589                 (void) strcpy(Announce, greeting);
 590                 (void) strcpy(Announce + sizeof(greeting) - 1, user);
 591 #undef greeting
 592
 593                 lctrl = ctrl | WINBIND__OLD_PASSWORD;
 594                 retval = _winbind_read_password(pamh, lctrl
 595                                                 ,Announce
 596                                                 ,"(current) NT password: "
 597                                                 ,NULL
 598                                                 ,(const char **) &pass_old);
 599                 free(Announce);
 600
 601                 if (retval != PAM_SUCCESS) {
 602                         _pam_log(LOG_NOTICE
 603                                  ,"password - (old) token not obtained");
 604                         return retval;
 605                 }
 606                 /* verify that this is the password for this user */
 607
 608                 retval = winbind_auth_request(user, pass_old, ctrl);
 609
 610                 if (retval != PAM_ACCT_EXPIRED
 611                     && retval != PAM_AUTHTOK_EXPIRED
 612                     && retval != PAM_NEW_AUTHTOK_REQD
 613                     && retval != PAM_SUCCESS) {
 614                         pass_old = NULL;
 615                         return retval;
 616                 }
 617
 618                 retval = pam_set_item(pamh, PAM_OLDAUTHTOK, (const void *) pass_old);
 619                 pass_old = NULL;
 620                 if (retval != PAM_SUCCESS) {
 621                         _pam_log(LOG_CRIT,
 622                                  "failed to set PAM_OLDAUTHTOK");
 623                 }
 624         } else if (flags & PAM_UPDATE_AUTHTOK) {
 625
 626                 /*
 627                  * obtain the proposed password
 628                  */
 629
 630                 /*
 631                  * get the old token back.
 632                  */
 633
 634                 retval = pam_get_item(pamh, PAM_OLDAUTHTOK
 635                                       ,(const void **) &pass_old);
 636
 637                 if (retval != PAM_SUCCESS) {
 638                         _pam_log(LOG_NOTICE, "user not authenticated");
 639                         return retval;
 640                 }
 641
 642                 lctrl = ctrl;
 643
 644                 if (on(WINBIND_USE_AUTHTOK_ARG, lctrl)) {
 645                         ctrl = WINBIND_USE_FIRST_PASS_ARG | lctrl;
 646                 }
 647                 retry = 0;
 648                 retval = PAM_AUTHTOK_ERR;
 649                 while ((retval != PAM_SUCCESS) && (retry++ < MAX_PASSWD_TRIES)) {
 650                         /*
 651                          * use_authtok is to force the use of a previously entered
 652                          * password -- needed for pluggable password strength checking
 653                          */
 654
 655                         retval = _winbind_read_password(pamh, lctrl
 656                                                         ,NULL
 657                                                         ,"Enter new NT password: "
 658                                                         ,"Retype new NT password: "
 659                                                         ,(const char **) &pass_new);
 660
 661                         if (retval != PAM_SUCCESS) {
 662                                 if (on(WINBIND_DEBUG_ARG, ctrl)) {
 663                                         _pam_log(LOG_ALERT
 664                                                  ,"password - new password not obtained");
 665                                 }
 666                                 pass_old = NULL;/* tidy up */
 667                                 return retval;
 668                         }
 669
 670                         /*
 671                          * At this point we know who the user is and what they
 672                          * propose as their new password. Verify that the new
 673                          * password is acceptable.
 674                          */
 675
 676                         if (pass_new[0] == '\0') {/* "\0" password = NULL */
 677                                 pass_new = NULL;
 678                         }
 679                 }
 680
 681                 /*
 682                  * By reaching here we have approved the passwords and must now
 683                  * rebuild the password database file.
 684                  */
 685
 686                 retval = winbind_chauthtok_request(user, pass_old, pass_new, ctrl);
 687                 _pam_overwrite(pass_new);
 688                 _pam_overwrite(pass_old);
 689                 pass_old = pass_new = NULL;
 690         } else {
 691                 retval = PAM_SERVICE_ERR;
 692         }
 693
 694         return retval;
 695 }
 696
 697 #ifdef PAM_STATIC
 698
 699 /* static module data */
 700
 701 struct pam_module _pam_winbind_modstruct = {
 702      MODULE_NAME,
 703      pam_sm_authenticate,
 704      pam_sm_setcred,
 705      pam_sm_acct_mgmt,
 706      pam_sm_open_session,
 707      pam_sm_close_session,
 708      pam_sm_chauthtok
 709 };
 710
 711 #endif
 712
 713 /*
 714  * Copyright (c) Andrew Tridgell  <tridge@samba.org>   2000
 715  * Copyright (c) Tim Potter       <tpot@samba.org>     2000
 716  * Copyright (c) Andrew Bartlettt <abartlet@samba.org> 2002
 717  * Copyright (c) Jan Rêkorajski 1999.
 718  * Copyright (c) Andrew G. Morgan 1996-8.
 719  * Copyright (c) Alex O. Yuriev, 1996.
 720  * Copyright (c) Cristian Gafton 1996.
 721  * Copyright (C) Elliot Lee <sopwith@redhat.com> 1996, Red Hat Software.
 722  *
 723  * Redistribution and use in source and binary forms, with or without
 724  * modification, are permitted provided that the following conditions
 725  * are met:
 726  * 1. Redistributions of source code must retain the above copyright
 727  *    notice, and the entire permission notice in its entirety,
 728  *    including the disclaimer of warranties.
 729  * 2. Redistributions in binary form must reproduce the above copyright
 730  *    notice, this list of conditions and the following disclaimer in the
 731  *    documentation and/or other materials provided with the distribution.
 732  * 3. The name of the author may not be used to endorse or promote
 733  *    products derived from this software without specific prior
 734  *    written permission.
 735  *
 736  * ALTERNATIVELY, this product may be distributed under the terms of
 737  * the GNU Public License, in which case the provisions of the GPL are
 738  * required INSTEAD OF the above restrictions.  (This clause is
 739  * necessary due to a potential bad interaction between the GPL and
 740  * the restrictions contained in a BSD-style copyright.)
 741  *
 742  * THIS SOFTWARE IS PROVIDED `AS IS'' AND ANY EXPRESS OR IMPLIED
 743  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 744  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 745  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 746  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 747  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 748  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 749  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 750  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 751  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 752  * OF THE POSSIBILITY OF SUCH DAMAGE.
 753  */