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
  66 static char *smb_pam_copy_string(const char *s)
  67 {
  68         if (s == NULL) {
  69                 return NULL;
  70         }
  71         return SMB_STRDUP(s);
  72 }
  73
  74 static char *smb_pam_copy_fstring(const char *s)
  75 {
  76         if (s[0] == '\0') {
  77                 return NULL;
  78         }
  79         return SMB_STRDUP(s);
  80 }
  81
  82 /*******************************************************************
  83  PAM error handler.
  84  *********************************************************************/
  85
  86 static bool smb_pam_error_handler(pam_handle_t *pamh, int pam_error, const char *msg, int dbglvl)
  87 {
  88
  89         if( pam_error != PAM_SUCCESS) {
  90                 DEBUG(dbglvl, ("smb_pam_error_handler: PAM: %s : %s\n",
  91                                 msg, pam_strerror(pamh, pam_error)));
  92                 return False;
  93         }
  94         return True;
  95 }
  96
  97 /*******************************************************************
  98  This function is a sanity check, to make sure that we NEVER report
  99  failure as sucess.
 100 *********************************************************************/
 101
 102 static bool smb_pam_nt_status_error_handler(pam_handle_t *pamh, int pam_error,
 103                                             const char *msg, int dbglvl,
 104                                             NTSTATUS *nt_status)
 105 {
 106         *nt_status = pam_to_nt_status(pam_error);
 107
 108         if (smb_pam_error_handler(pamh, pam_error, msg, dbglvl))
 109                 return True;
 110
 111         if (NT_STATUS_IS_OK(*nt_status)) {
 112                 /* Complain LOUDLY */
 113                 DEBUG(0, ("smb_pam_nt_status_error_handler: PAM: BUG: PAM and NT_STATUS \
 114 error MISMATCH, forcing to NT_STATUS_LOGON_FAILURE"));
 115                 *nt_status = NT_STATUS_LOGON_FAILURE;
 116         }
 117         return False;
 118 }
 119
 120 /*
 121  * PAM conversation function
 122  * Here we assume (for now, at least) that echo on means login name, and
 123  * echo off means password.
 124  */
 125
 126 static int smb_pam_conv(int num_msg,
 127                     const struct pam_message **msg,
 128                     struct pam_response **resp,
 129                     void *appdata_ptr)
 130 {
 131         int replies = 0;
 132         struct pam_response *reply = NULL;
 133         struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
 134
 135         *resp = NULL;
 136
 137         if (num_msg <= 0)
 138                 return PAM_CONV_ERR;
 139
 140         /*
 141          * Apparantly HPUX has a buggy PAM that doesn't support the
 142          * appdata_ptr. Fail if this is the case. JRA.
 143          */
 144
 145         if (udp == NULL) {
 146                 DEBUG(0,("smb_pam_conv: PAM on this system is broken - appdata_ptr == NULL !\n"));
 147                 return PAM_CONV_ERR;
 148         }
 149
 150         reply = SMB_MALLOC_ARRAY(struct pam_response, num_msg);
 151         if (!reply)
 152                 return PAM_CONV_ERR;
 153
 154         memset(reply, '\0', sizeof(struct pam_response) * num_msg);
 155
 156         for (replies = 0; replies < num_msg; replies++) {
 157                 switch (msg[replies]->msg_style) {
 158                         case PAM_PROMPT_ECHO_ON:
 159                                 reply[replies].resp_retcode = PAM_SUCCESS;
 160                                 reply[replies].resp = smb_pam_copy_string(
 161                                         udp->PAM_username);
 162                                 /* PAM frees resp */
 163                                 break;
 164
 165                         case PAM_PROMPT_ECHO_OFF:
 166                                 reply[replies].resp_retcode = PAM_SUCCESS;
 167                                 reply[replies].resp = smb_pam_copy_string(
 168                                         udp->PAM_password);
 169                                 /* PAM frees resp */
 170                                 break;
 171
 172                         case PAM_TEXT_INFO:
 173                                 /* fall through */
 174
 175                         case PAM_ERROR_MSG:
 176                                 /* ignore it... */
 177                                 reply[replies].resp_retcode = PAM_SUCCESS;
 178                                 reply[replies].resp = NULL;
 179                                 break;
 180
 181                         default:
 182                                 /* Must be an error of some sort... */
 183                                 SAFE_FREE(reply);
 184                                 return PAM_CONV_ERR;
 185                 }
 186         }
 187         if (reply)
 188                 *resp = reply;
 189         return PAM_SUCCESS;
 190 }
 191
 192 /*
 193  * PAM password change conversation function
 194  * Here we assume (for now, at least) that echo on means login name, and
 195  * echo off means password.
 196  */
 197
 198 static void special_char_sub(char *buf)
 199 {
 200         all_string_sub(buf, "\\n", "", 0);
 201         all_string_sub(buf, "\\r", "", 0);
 202         all_string_sub(buf, "\\s", " ", 0);
 203         all_string_sub(buf, "\\t", "\t", 0);
 204 }
 205
 206 static void pwd_sub(char *buf, const char *username, const char *oldpass, const char *newpass)
 207 {
 208         fstring_sub(buf, "%u", username);
 209         all_string_sub(buf, "%o", oldpass, sizeof(fstring));
 210         all_string_sub(buf, "%n", newpass, sizeof(fstring));
 211 }
 212
 213
 214 struct chat_struct {
 215         struct chat_struct *next, *prev;
 216         fstring prompt;
 217         fstring reply;
 218 };
 219
 220 /**************************************************************
 221  Create a linked list containing chat data.
 222 ***************************************************************/
 223
 224 static struct chat_struct *make_pw_chat(const char *p)
 225 {
 226         char *prompt;
 227         char *reply;
 228         struct chat_struct *list = NULL;
 229         struct chat_struct *t;
 230         TALLOC_CTX *frame = talloc_stackframe();
 231
 232         while (1) {
 233                 t = SMB_MALLOC_P(struct chat_struct);
 234                 if (!t) {
 235                         DEBUG(0,("make_pw_chat: malloc failed!\n"));
 236                         TALLOC_FREE(frame);
 237                         return NULL;
 238                 }
 239
 240                 ZERO_STRUCTP(t);
 241
 242                 DLIST_ADD_END(list, t, struct chat_struct*);
 243
 244                 if (!next_token_talloc(frame, &p, &prompt, NULL)) {
 245                         break;
 246                 }
 247
 248                 if (strequal(prompt,".")) {
 249                         fstrcpy(prompt,"*");
 250                 }
 251
 252                 special_char_sub(prompt);
 253                 fstrcpy(t->prompt, prompt);
 254                 strlower_m(t->prompt);
 255                 trim_char(t->prompt, ' ', ' ');
 256
 257                 if (!next_token_talloc(frame, &p, &reply, NULL)) {
 258                         break;
 259                 }
 260
 261                 if (strequal(reply,".")) {
 262                         fstrcpy(reply,"");
 263                 }
 264
 265                 special_char_sub(reply);
 266                 fstrcpy(t->reply, reply);
 267                 strlower_m(t->reply);
 268                 trim_char(t->reply, ' ', ' ');
 269
 270         }
 271         TALLOC_FREE(frame);
 272         return list;
 273 }
 274
 275 static void free_pw_chat(struct chat_struct *list)
 276 {
 277     while (list) {
 278         struct chat_struct *old_head = list;
 279         DLIST_REMOVE(list, list);
 280         SAFE_FREE(old_head);
 281     }
 282 }
 283
 284 static int smb_pam_passchange_conv(int num_msg,
 285                                 const struct pam_message **msg,
 286                                 struct pam_response **resp,
 287                                 void *appdata_ptr)
 288 {
 289         int replies = 0;
 290         struct pam_response *reply = NULL;
 291         fstring current_prompt;
 292         fstring current_reply;
 293         struct smb_pam_userdata *udp = (struct smb_pam_userdata *)appdata_ptr;
 294         struct chat_struct *pw_chat;
 295         struct chat_struct *t;
 296         bool found;
 297         *resp = NULL;
 298
 299         DEBUG(10,("smb_pam_passchange_conv: starting converstation for %d messages\n", num_msg));
 300
 301         if (num_msg <= 0)
 302                 return PAM_CONV_ERR;
 303
 304         if ((pw_chat = make_pw_chat(lp_passwd_chat())) == NULL)
 305                 return PAM_CONV_ERR;
 306
 307         /*
 308          * Apparantly HPUX has a buggy PAM that doesn't support the
 309          * appdata_ptr. Fail if this is the case. JRA.
 310          */
 311
 312         if (udp == NULL) {
 313                 DEBUG(0,("smb_pam_passchange_conv: PAM on this system is broken - appdata_ptr == NULL !\n"));
 314                 free_pw_chat(pw_chat);
 315                 return PAM_CONV_ERR;
 316         }
 317
 318         reply = SMB_MALLOC_ARRAY(struct pam_response, num_msg);
 319         if (!reply) {
 320                 DEBUG(0,("smb_pam_passchange_conv: malloc for reply failed!\n"));
 321                 free_pw_chat(pw_chat);
 322                 return PAM_CONV_ERR;
 323         }
 324
 325         for (replies = 0; replies < num_msg; replies++) {
 326                 found = False;
 327                 DEBUG(10,("smb_pam_passchange_conv: Processing message %d\n", replies));
 328                 switch (msg[replies]->msg_style) {
 329                 case PAM_PROMPT_ECHO_ON:
 330                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: PAM said: %s\n", msg[replies]->msg));
 331                         fstrcpy(current_prompt, msg[replies]->msg);
 332                         trim_char(current_prompt, ' ', ' ');
 333                         for (t=pw_chat; t; t=t->next) {
 334
 335                                 DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: trying to match |%s| to |%s|\n",
 336                                                 t->prompt, current_prompt ));
 337
 338                                 if (unix_wild_match(t->prompt, current_prompt)) {
 339                                         fstrcpy(current_reply, t->reply);
 340                                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: We sent: %s\n", current_reply));
 341                                         pwd_sub(current_reply, udp->PAM_username, udp->PAM_password, udp->PAM_newpassword);
 342 #ifdef DEBUG_PASSWORD
 343                                         DEBUG(100,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_ON: We actualy sent: %s\n", current_reply));
 344 #endif
 345                                         reply[replies].resp_retcode = PAM_SUCCESS;
 346                                         reply[replies].resp = smb_pam_copy_fstring(
 347                                                 current_reply);
 348                                         found = True;
 349                                         break;
 350                                 }
 351                         }
 352                         /* PAM frees resp */
 353                         if (!found) {
 354                                 DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
 355                                 free_pw_chat(pw_chat);
 356                                 SAFE_FREE(reply);
 357                                 return PAM_CONV_ERR;
 358                         }
 359                         break;
 360
 361                 case PAM_PROMPT_ECHO_OFF:
 362                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: PAM said: %s\n", msg[replies]->msg));
 363                         fstrcpy(current_prompt, msg[replies]->msg);
 364                         trim_char(current_prompt, ' ', ' ');
 365                         for (t=pw_chat; t; t=t->next) {
 366
 367                                 DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: trying to match |%s| to |%s|\n",
 368                                                 t->prompt, current_prompt ));
 369
 370                                 if (unix_wild_match(t->prompt, current_prompt)) {
 371                                         fstrcpy(current_reply, t->reply);
 372                                         DEBUG(10,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: We sent: %s\n", current_reply));
 373                                         pwd_sub(current_reply, udp->PAM_username, udp->PAM_password, udp->PAM_newpassword);
 374                                         reply[replies].resp_retcode = PAM_SUCCESS;
 375                                         reply[replies].resp = smb_pam_copy_fstring(
 376                                                 current_reply);
 377 #ifdef DEBUG_PASSWORD
 378                                         DEBUG(100,("smb_pam_passchange_conv: PAM_PROMPT_ECHO_OFF: We actualy sent: %s\n", current_reply));
 379 #endif
 380                                         found = True;
 381                                         break;
 382                                 }
 383                         }
 384                         /* PAM frees resp */
 385
 386                         if (!found) {
 387                                 DEBUG(3,("smb_pam_passchange_conv: Could not find reply for PAM prompt: %s\n",msg[replies]->msg));
 388                                 free_pw_chat(pw_chat);
 389                                 SAFE_FREE(reply);
 390                                 return PAM_CONV_ERR;
 391                         }
 392                         break;
 393
 394                 case PAM_TEXT_INFO:
 395                         /* fall through */
 396
 397                 case PAM_ERROR_MSG:
 398                         /* ignore it... */
 399                         reply[replies].resp_retcode = PAM_SUCCESS;
 400                         reply[replies].resp = NULL;
 401                         break;
 402
 403                 default:
 404                         /* Must be an error of some sort... */
 405                         free_pw_chat(pw_chat);
 406                         SAFE_FREE(reply);
 407                         return PAM_CONV_ERR;
 408                 }
 409         }
 410
 411         free_pw_chat(pw_chat);
 412         if (reply)
 413                 *resp = reply;
 414         return PAM_SUCCESS;
 415 }
 416
 417 /***************************************************************************
 418  Free up a malloced pam_conv struct.
 419 ****************************************************************************/
 420
 421 static void smb_free_pam_conv(struct pam_conv *pconv)
 422 {
 423         if (pconv)
 424                 SAFE_FREE(pconv->appdata_ptr);
 425
 426         SAFE_FREE(pconv);
 427 }
 428
 429 /***************************************************************************
 430  Allocate a pam_conv struct.
 431 ****************************************************************************/
 432
 433 static struct pam_conv *smb_setup_pam_conv(smb_pam_conv_fn smb_pam_conv_fnptr, const char *user,
 434                                         const char *passwd, const char *newpass)
 435 {
 436         struct pam_conv *pconv = SMB_MALLOC_P(struct pam_conv);
 437         struct smb_pam_userdata *udp = SMB_MALLOC_P(struct smb_pam_userdata);
 438
 439         if (pconv == NULL || udp == NULL) {
 440                 SAFE_FREE(pconv);
 441                 SAFE_FREE(udp);
 442                 return NULL;
 443         }
 444
 445         udp->PAM_username = user;
 446         udp->PAM_password = passwd;
 447         udp->PAM_newpassword = newpass;
 448
 449         pconv->conv = smb_pam_conv_fnptr;
 450         pconv->appdata_ptr = (void *)udp;
 451         return pconv;
 452 }
 453
 454 /*
 455  * PAM Closing out cleanup handler
 456  */
 457
 458 static bool smb_pam_end(pam_handle_t *pamh, struct pam_conv *smb_pam_conv_ptr)
 459 {
 460         int pam_error;
 461
 462         smb_free_pam_conv(smb_pam_conv_ptr);
 463
 464         if( pamh != NULL ) {
 465                 pam_error = pam_end(pamh, 0);
 466                 if(smb_pam_error_handler(pamh, pam_error, "End Cleanup Failed", 2) == True) {
 467                         DEBUG(4, ("smb_pam_end: PAM: PAM_END OK.\n"));
 468                         return True;
 469                 }
 470         }
 471         DEBUG(2,("smb_pam_end: PAM: not initialised"));
 472         return False;
 473 }
 474
 475 /*
 476  * Start PAM authentication for specified account
 477  */
 478
 479 static bool smb_pam_start(pam_handle_t **pamh, const char *user, const char *rhost, struct pam_conv *pconv)
 480 {
 481         int pam_error;
 482 #ifdef PAM_RHOST
 483         const char *our_rhost;
 484         char addr[INET6_ADDRSTRLEN];
 485 #endif
 486
 487         *pamh = (pam_handle_t *)NULL;
 488
 489         DEBUG(4,("smb_pam_start: PAM: Init user: %s\n", user));
 490
 491         pam_error = pam_start("samba", user, pconv, pamh);
 492         if( !smb_pam_error_handler(*pamh, pam_error, "Init Failed", 0)) {
 493                 *pamh = (pam_handle_t *)NULL;
 494                 return False;
 495         }
 496
 497 #if HAVE_PAM_RHOST
 498         if (rhost == NULL) {
 499                 our_rhost = client_name(smbd_server_fd());
 500                 if (strequal(our_rhost,"UNKNOWN"))
 501                         our_rhost = client_addr(smbd_server_fd(), addr,
 502                                                 sizeof(addr));
 503         } else {
 504                 our_rhost = rhost;
 505         }
 506
 507         DEBUG(4,("smb_pam_start: PAM: setting rhost to: %s\n", our_rhost));
 508         pam_error = pam_set_item(*pamh, PAM_RHOST, our_rhost);
 509         if(!smb_pam_error_handler(*pamh, pam_error, "set rhost failed", 0)) {
 510                 smb_pam_end(*pamh, pconv);
 511                 *pamh = (pam_handle_t *)NULL;
 512                 return False;
 513         }
 514 #endif
 515 #if HAVE_PAM_TTY
 516         DEBUG(4,("smb_pam_start: PAM: setting tty\n"));
 517         pam_error = pam_set_item(*pamh, PAM_TTY, "samba");
 518         if (!smb_pam_error_handler(*pamh, pam_error, "set tty failed", 0)) {
 519                 smb_pam_end(*pamh, pconv);
 520                 *pamh = (pam_handle_t *)NULL;
 521                 return False;
 522         }
 523 #endif
 524         DEBUG(4,("smb_pam_start: PAM: Init passed for user: %s\n", user));
 525         return True;
 526 }
 527
 528 /*
 529  * PAM Authentication Handler
 530  */
 531 static NTSTATUS smb_pam_auth(pam_handle_t *pamh, const char *user)
 532 {
 533         int pam_error;
 534         NTSTATUS nt_status = NT_STATUS_LOGON_FAILURE;
 535
 536         /*
 537          * To enable debugging set in /etc/pam.d/samba:
 538          *      auth required /lib/security/pam_pwdb.so nullok shadow audit
 539          */
 540
 541         DEBUG(4,("smb_pam_auth: PAM: Authenticate User: %s\n", user));
 542         pam_error = pam_authenticate(pamh, PAM_SILENT | lp_null_passwords() ? 0 : PAM_DISALLOW_NULL_AUTHTOK);
 543         switch( pam_error ){
 544                 case PAM_AUTH_ERR:
 545                         DEBUG(2, ("smb_pam_auth: PAM: Authentication Error for user %s\n", user));
 546                         break;
 547                 case PAM_CRED_INSUFFICIENT:
 548                         DEBUG(2, ("smb_pam_auth: PAM: Insufficient Credentials for user %s\n", user));
 549                         break;
 550                 case PAM_AUTHINFO_UNAVAIL:
 551                         DEBUG(2, ("smb_pam_auth: PAM: Authentication Information Unavailable for user %s\n", user));
 552                         break;
 553                 case PAM_USER_UNKNOWN:
 554                         DEBUG(2, ("smb_pam_auth: PAM: Username %s NOT known to Authentication system\n", user));
 555                         break;
 556                 case PAM_MAXTRIES:
 557                         DEBUG(2, ("smb_pam_auth: PAM: One or more authentication modules reports user limit for user %s exceeeded\n", user));
 558                         break;
 559                 case PAM_ABORT:
 560                         DEBUG(0, ("smb_pam_auth: PAM: One or more PAM modules failed to load for user %s\n", user));
 561                         break;
 562                 case PAM_SUCCESS:
 563                         DEBUG(4, ("smb_pam_auth: PAM: User %s Authenticated OK\n", user));
 564                         break;
 565                 default:
 566                         DEBUG(0, ("smb_pam_auth: PAM: UNKNOWN ERROR while authenticating user %s\n", user));
 567                         break;
 568         }
 569
 570         smb_pam_nt_status_error_handler(pamh, pam_error, "Authentication Failure", 2, &nt_status);
 571         return nt_status;
 572 }
 573
 574 /*
 575  * PAM Account Handler
 576  */
 577 static NTSTATUS smb_pam_account(pam_handle_t *pamh, const char * user)
 578 {
 579         int pam_error;
 580         NTSTATUS nt_status = NT_STATUS_ACCOUNT_DISABLED;
 581
 582         DEBUG(4,("smb_pam_account: PAM: Account Management for User: %s\n", user));
 583         pam_error = pam_acct_mgmt(pamh, PAM_SILENT); /* Is user account enabled? */
 584         switch( pam_error ) {
 585                 case PAM_AUTHTOK_EXPIRED:
 586                         DEBUG(2, ("smb_pam_account: PAM: User %s is valid but password is expired\n", user));
 587                         break;
 588                 case PAM_ACCT_EXPIRED:
 589                         DEBUG(2, ("smb_pam_account: PAM: User %s no longer permitted to access system\n", user));
 590                         break;
 591                 case PAM_AUTH_ERR:
 592                         DEBUG(2, ("smb_pam_account: PAM: There was an authentication error for user %s\n", user));
 593                         break;
 594                 case PAM_PERM_DENIED:
 595                         DEBUG(0, ("smb_pam_account: PAM: User %s is NOT permitted to access system at this time\n", user));
 596                         break;
 597                 case PAM_USER_UNKNOWN:
 598                         DEBUG(0, ("smb_pam_account: PAM: User \"%s\" is NOT known to account management\n", user));
 599                         break;
 600                 case PAM_SUCCESS:
 601                         DEBUG(4, ("smb_pam_account: PAM: Account OK for User: %s\n", user));
 602                         break;
 603                 default:
 604                         DEBUG(0, ("smb_pam_account: PAM: UNKNOWN PAM ERROR (%d) during Account Management for User: %s\n", pam_error, user));
 605                         break;
 606         }
 607
 608         smb_pam_nt_status_error_handler(pamh, pam_error, "Account Check Failed", 2, &nt_status);
 609         return nt_status;
 610 }
 611
 612 /*
 613  * PAM Credential Setting
 614  */
 615
 616 static NTSTATUS smb_pam_setcred(pam_handle_t *pamh, const char * user)
 617 {
 618         int pam_error;
 619         NTSTATUS nt_status = NT_STATUS_NO_TOKEN;
 620
 621         /*
 622          * This will allow samba to aquire a kerberos token. And, when
 623          * exporting an AFS cell, be able to /write/ to this cell.
 624          */
 625
 626         DEBUG(4,("PAM: Account Management SetCredentials for User: %s\n", user));
 627         pam_error = pam_setcred(pamh, (PAM_ESTABLISH_CRED|PAM_SILENT));
 628         switch( pam_error ) {
 629                 case PAM_CRED_UNAVAIL:
 630                         DEBUG(0, ("smb_pam_setcred: PAM: Credentials not found for user:%s\n", user ));
 631                         break;
 632                 case PAM_CRED_EXPIRED:
 633                         DEBUG(0, ("smb_pam_setcred: PAM: Credentials for user: \"%s\" EXPIRED!\n", user ));
 634                         break;
 635                 case PAM_USER_UNKNOWN:
 636                         DEBUG(0, ("smb_pam_setcred: PAM: User: \"%s\" is NOT known so can not set credentials!\n", user ));
 637                         break;
 638                 case PAM_CRED_ERR:
 639                         DEBUG(0, ("smb_pam_setcred: PAM: Unknown setcredentials error - unable to set credentials for %s\n", user ));
 640                         break;
 641                 case PAM_SUCCESS:
 642                         DEBUG(4, ("smb_pam_setcred: PAM: SetCredentials OK for User: %s\n", user));
 643                         break;
 644                 default:
 645                         DEBUG(0, ("smb_pam_setcred: PAM: UNKNOWN PAM ERROR (%d) during SetCredentials for User: %s\n", pam_error, user));
 646                         break;
 647         }
 648
 649         smb_pam_nt_status_error_handler(pamh, pam_error, "Set Credential Failure", 2, &nt_status);
 650         return nt_status;
 651 }
 652
 653 /*
 654  * PAM Internal Session Handler
 655  */
 656 static bool smb_internal_pam_session(pam_handle_t *pamh, const char *user, const char *tty, bool flag)
 657 {
 658         int pam_error;
 659
 660 #if HAVE_PAM_TTY
 661         DEBUG(4,("smb_internal_pam_session: PAM: tty set to: %s\n", tty));
 662         pam_error = pam_set_item(pamh, PAM_TTY, tty);
 663         if (!smb_pam_error_handler(pamh, pam_error, "set tty failed", 0))
 664                 return False;
 665 #endif
 666
 667         if (flag) {
 668                 pam_error = pam_open_session(pamh, PAM_SILENT);
 669                 if (!smb_pam_error_handler(pamh, pam_error, "session setup failed", 0))
 670                         return False;
 671         } else {
 672                 pam_setcred(pamh, (PAM_DELETE_CRED|PAM_SILENT)); /* We don't care if this fails */
 673                 pam_error = pam_close_session(pamh, PAM_SILENT); /* This will probably pick up the error anyway */
 674                 if (!smb_pam_error_handler(pamh, pam_error, "session close failed", 0))
 675                         return False;
 676         }
 677         return (True);
 678 }
 679
 680 /*
 681  * Internal PAM Password Changer.
 682  */
 683
 684 static bool smb_pam_chauthtok(pam_handle_t *pamh, const char * user)
 685 {
 686         int pam_error;
 687
 688         DEBUG(4,("smb_pam_chauthtok: PAM: Password Change for User: %s\n", user));
 689
 690         pam_error = pam_chauthtok(pamh, PAM_SILENT); /* Change Password */
 691
 692         switch( pam_error ) {
 693         case PAM_AUTHTOK_ERR:
 694                 DEBUG(2, ("PAM: unable to obtain the new authentication token - is password to weak?\n"));
 695                 break;
 696
 697         /* This doesn't seem to be defined on Solaris. JRA */
 698 #ifdef PAM_AUTHTOK_RECOVER_ERR
 699         case PAM_AUTHTOK_RECOVER_ERR:
 700                 DEBUG(2, ("PAM: unable to obtain the old authentication token - was the old password wrong?.\n"));
 701                 break;
 702 #endif
 703
 704         case PAM_AUTHTOK_LOCK_BUSY:
 705                 DEBUG(2, ("PAM: unable to change the authentication token since it is currently locked.\n"));
 706                 break;
 707         case PAM_AUTHTOK_DISABLE_AGING:
 708                 DEBUG(2, ("PAM: Authentication token aging has been disabled.\n"));
 709                 break;
 710         case PAM_PERM_DENIED:
 711                 DEBUG(0, ("PAM: Permission denied.\n"));
 712                 break;
 713         case PAM_TRY_AGAIN:
 714                 DEBUG(0, ("PAM: Could not update all authentication token(s). No authentication tokens were updated.\n"));
 715                 break;
 716         case PAM_USER_UNKNOWN:
 717                 DEBUG(0, ("PAM: User not known to PAM\n"));
 718                 break;
 719         case PAM_SUCCESS:
 720                 DEBUG(4, ("PAM: Account OK for User: %s\n", user));
 721                 break;
 722         default:
 723                 DEBUG(0, ("PAM: UNKNOWN PAM ERROR (%d) for User: %s\n", pam_error, user));
 724         }
 725
 726         if(!smb_pam_error_handler(pamh, pam_error, "Password Change Failed", 2)) {
 727                 return False;
 728         }
 729
 730         /* If this point is reached, the password has changed. */
 731         return True;
 732 }
 733
 734 /*
 735  * PAM Externally accessible Session handler
 736  */
 737
 738 bool smb_pam_claim_session(char *user, char *tty, char *rhost)
 739 {
 740         pam_handle_t *pamh = NULL;
 741         struct pam_conv *pconv = NULL;
 742
 743         /* Ignore PAM if told to. */
 744
 745         if (!lp_obey_pam_restrictions())
 746                 return True;
 747
 748         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
 749                 return False;
 750
 751         if (!smb_pam_start(&pamh, user, rhost, pconv))
 752                 return False;
 753
 754         if (!smb_internal_pam_session(pamh, user, tty, True)) {
 755                 smb_pam_end(pamh, pconv);
 756                 return False;
 757         }
 758
 759         return smb_pam_end(pamh, pconv);
 760 }
 761
 762 /*
 763  * PAM Externally accessible Session handler
 764  */
 765
 766 bool smb_pam_close_session(char *user, char *tty, char *rhost)
 767 {
 768         pam_handle_t *pamh = NULL;
 769         struct pam_conv *pconv = NULL;
 770
 771         /* Ignore PAM if told to. */
 772
 773         if (!lp_obey_pam_restrictions())
 774                 return True;
 775
 776         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
 777                 return False;
 778
 779         if (!smb_pam_start(&pamh, user, rhost, pconv))
 780                 return False;
 781
 782         if (!smb_internal_pam_session(pamh, user, tty, False)) {
 783                 smb_pam_end(pamh, pconv);
 784                 return False;
 785         }
 786
 787         return smb_pam_end(pamh, pconv);
 788 }
 789
 790 /*
 791  * PAM Externally accessible Account handler
 792  */
 793
 794 NTSTATUS smb_pam_accountcheck(const char *user, const char *rhost)
 795 {
 796         NTSTATUS nt_status = NT_STATUS_ACCOUNT_DISABLED;
 797         pam_handle_t *pamh = NULL;
 798         struct pam_conv *pconv = NULL;
 799
 800         /* Ignore PAM if told to. */
 801
 802         if (!lp_obey_pam_restrictions())
 803                 return NT_STATUS_OK;
 804
 805         if ((pconv = smb_setup_pam_conv(smb_pam_conv, user, NULL, NULL)) == NULL)
 806                 return NT_STATUS_NO_MEMORY;
 807
 808         if (!smb_pam_start(&pamh, user, rhost, pconv))
 809                 return NT_STATUS_ACCOUNT_DISABLED;
 810
 811         if (!NT_STATUS_IS_OK(nt_status = smb_pam_account(pamh, user)))
 812                 DEBUG(0, ("smb_pam_accountcheck: PAM: Account Validation Failed - Rejecting User %s!\n", user));
 813
 814         smb_pam_end(pamh, pconv);
 815         return nt_status;
 816 }
 817
 818 /*
 819  * PAM Password Validation Suite
 820  */
 821
 822 NTSTATUS smb_pam_passcheck(const char * user, 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, NULL, 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 * oldpassword, const char * newpassword)
 867 {
 868         /* Appropriate quantities of root should be obtained BEFORE calling this function */
 869         struct pam_conv *pconv = NULL;
 870         pam_handle_t *pamh = NULL;
 871
 872         if ((pconv = smb_setup_pam_conv(smb_pam_passchange_conv, user, oldpassword, newpassword)) == NULL)
 873                 return False;
 874
 875         if(!smb_pam_start(&pamh, user, NULL, pconv))
 876                 return False;
 877
 878         if (!smb_pam_chauthtok(pamh, user)) {
 879                 DEBUG(0, ("smb_pam_passchange: PAM: Password Change Failed for user %s!\n", user));
 880                 smb_pam_end(pamh, pconv);
 881                 return False;
 882         }
 883
 884         return smb_pam_end(pamh, pconv);
 885 }
 886
 887 #else
 888
 889 /* If PAM not used, no PAM restrictions on accounts. */
 890 NTSTATUS smb_pam_accountcheck(const char *user, const char *rhost)
 891 {
 892         return NT_STATUS_OK;
 893 }
 894
 895 /* If PAM not used, also no PAM restrictions on sessions. */
 896 bool smb_pam_claim_session(char *user, char *tty, char *rhost)
 897 {
 898         return True;
 899 }
 900
 901 /* If PAM not used, also no PAM restrictions on sessions. */
 902 bool smb_pam_close_session(char *in_user, char *tty, char *rhost)
 903 {
 904         return True;
 905 }
 906 #endif /* WITH_PAM */