source/lib/username.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Username handling
   5    Copyright (C) Andrew Tridgell 1992-1998
   6    Copyright (C) Jeremy Allison 1997-2001.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24
  25 /* internal functions */
  26 static struct passwd *uname_string_combinations(char *s, struct passwd * (*fn) (char *), int N);
  27 static struct passwd *uname_string_combinations2(char *s, int offset, struct passwd * (*fn) (char *), int N);
  28
  29 /*****************************************************************
  30  Check if a user or group name is local (this is a *local* name for
  31  *local* people, there's nothing for you here...).
  32 *****************************************************************/
  33
  34 BOOL name_is_local(const char *name)
  35 {
  36         return !strchr(name, *lp_winbind_separator());
  37 }
  38
  39 /****************************************************************************
  40  Get a users home directory.
  41 ****************************************************************************/
  42
  43 char *get_user_home_dir(char *user)
  44 {
  45         static struct passwd *pass;
  46
  47         pass = Get_Pwnam(user, False);
  48         if (!pass)
  49                 return(NULL);
  50         /* Return home directory from struct passwd. */
  51         return(pass->pw_dir);
  52 }
  53
  54 /****************************************************************************
  55  Get a users home service directory.
  56 ****************************************************************************/
  57
  58 char *get_user_service_home_dir(char *user)
  59 {
  60         static struct passwd *pass;
  61         int snum;
  62
  63         /* Ensure the user exists. */
  64
  65         pass = Get_Pwnam(user, False);
  66         if (!pass)
  67                 return(NULL);
  68
  69         /* If a path is specified in [homes] then use it instead of the
  70            user's home directory from struct passwd. */
  71
  72         if ((snum = lp_servicenumber(HOMES_NAME)) != -1) {
  73                 static pstring home_dir;
  74
  75                 pstrcpy(home_dir, lp_pathname(snum));
  76                 standard_sub_home(snum, user, home_dir, sizeof(home_dir));
  77
  78                 if (home_dir[0])
  79                         return home_dir;
  80         }
  81
  82         /* Return home directory from struct passwd. */
  83
  84         return(pass->pw_dir);
  85 }
  86
  87 /*******************************************************************
  88  Map a username from a dos name to a unix name by looking in the username
  89  map. Note that this modifies the name in place.
  90  This is the main function that should be called *once* on
  91  any incoming or new username - in order to canonicalize the name.
  92  This is being done to de-couple the case conversions from the user mapping
  93  function. Previously, the map_username was being called
  94  every time Get_Pwnam was called.
  95  Returns True if username was changed, false otherwise.
  96 ********************************************************************/
  97
  98 BOOL map_username(char *user)
  99 {
 100         static BOOL initialised=False;
 101         static fstring last_from,last_to;
 102         FILE *f;
 103         char *mapfile = lp_username_map();
 104         char *s;
 105         pstring buf;
 106         BOOL mapped_user = False;
 107
 108         if (!*user)
 109                 return False;
 110
 111         if (!*mapfile)
 112                 return False;
 113
 114         if (!initialised) {
 115                 *last_from = *last_to = 0;
 116                 initialised = True;
 117         }
 118
 119         if (strequal(user,last_to))
 120                 return False;
 121
 122         if (strequal(user,last_from)) {
 123                 DEBUG(3,("Mapped user %s to %s\n",user,last_to));
 124                 fstrcpy(user,last_to);
 125                 return True;
 126         }
 127
 128         f = sys_fopen(mapfile,"r");
 129         if (!f) {
 130                 DEBUG(0,("can't open username map %s. Error %s\n",mapfile, strerror(errno) ));
 131                 return False;
 132         }
 133
 134         DEBUG(4,("Scanning username map %s\n",mapfile));
 135
 136         while((s=fgets_slash(buf,sizeof(buf),f))!=NULL) {
 137                 char *unixname = s;
 138                 char *dosname = strchr(unixname,'=');
 139                 BOOL return_if_mapped = False;
 140
 141                 if (!dosname)
 142                         continue;
 143
 144                 *dosname++ = 0;
 145
 146                 while (isspace((int)*unixname))
 147                         unixname++;
 148                 if ('!' == *unixname) {
 149                         return_if_mapped = True;
 150                         unixname++;
 151
 152                         while (*unixname && isspace((int)*unixname))
 153                                 unixname++;
 154                 }
 155
 156                 if (!*unixname || strchr("#;",*unixname))
 157                         continue;
 158
 159                 {
 160                         int l = strlen(unixname);
 161                         while (l && isspace((int)unixname[l-1])) {
 162                                 unixname[l-1] = 0;
 163                                 l--;
 164                         }
 165                 }
 166
 167                 if (strchr(dosname,'*') || user_in_list(user,dosname)) {
 168                         DEBUG(3,("Mapped user %s to %s\n",user,unixname));
 169                         mapped_user = True;
 170                         fstrcpy(last_from,user);
 171                         sscanf(unixname,"%s",user);
 172                         fstrcpy(last_to,user);
 173                         if(return_if_mapped) {
 174                                 fclose(f);
 175                                 return True;
 176                         }
 177                 }
 178         }
 179
 180         fclose(f);
 181
 182         /*
 183          * Setup the last_from and last_to as an optimization so
 184          * that we don't scan the file again for the same user.
 185          */
 186         fstrcpy(last_from,user);
 187         fstrcpy(last_to,user);
 188
 189         return mapped_user;
 190 }
 191
 192 /****************************************************************************
 193  Get_Pwnam wrapper.
 194 ****************************************************************************/
 195
 196 static struct passwd *_Get_Pwnam(char *s)
 197 {
 198         struct passwd *ret;
 199
 200         ret = sys_getpwnam(s);
 201         if (ret) {
 202 #ifdef HAVE_GETPWANAM
 203                 struct passwd_adjunct *pwret;
 204                 pwret = getpwanam(s);
 205                 if (pwret && pwret->pwa_passwd)
 206                         pstrcpy(ret->pw_passwd,pwret->pwa_passwd);
 207 #endif
 208         }
 209
 210         return(ret);
 211 }
 212
 213 /****************************************************************************
 214  A wrapper for getpwnam().  The following variations are tried...
 215     - in all lower case
 216     - as transmitted IF a different case
 217     - in all upper case IF that is different from the transmitted username
 218     - using the lp_usernamelevel() for permutations
 219  Note that this can change user! The user name is in Unix code page.
 220 ****************************************************************************/
 221
 222 struct passwd *Get_Pwnam(char *user,BOOL allow_change)
 223 {
 224         fstring         user2, orig_username;
 225         int             usernamelevel = lp_usernamelevel();
 226         struct          passwd *ret;
 227
 228         if (!user || !(*user))
 229                 return(NULL);
 230
 231         /* make a few copies to work with */
 232         fstrcpy(orig_username, user);
 233         if (!allow_change) {
 234                 /* allow_change was False, so make a copy and temporarily
 235                    assign the char* user to the temp copy */
 236                 fstrcpy(user2,user);
 237                 user = &user2[0];
 238         }
 239
 240         /* try in all lower case first as this is the most
 241            common case on UNIX systems */
 242         unix_to_dos(user);
 243         strlower(user);
 244         dos_to_unix(user);
 245
 246         ret = _Get_Pwnam(user);
 247         if (ret)
 248                 return(ret);
 249
 250         /* try as transmitted, but only if the original username
 251            gives us a different case */
 252         if (strcmp(user, orig_username) != 0) {
 253                 ret = _Get_Pwnam(orig_username);
 254                 if (ret) {
 255                         if (allow_change)
 256                                 fstrcpy(user, orig_username);
 257
 258                         return(ret);
 259                 }
 260         }
 261
 262         /* finally, try in all caps if that is a new case */
 263         unix_to_dos(user);
 264         strupper(user);
 265         dos_to_unix(user);
 266
 267         if (strcmp(user, orig_username) != 0) {
 268                 ret = _Get_Pwnam(user);
 269                 if (ret)
 270                         return(ret);
 271         }
 272
 273         /* Try all combinations up to usernamelevel. */
 274         unix_to_dos(user);
 275         strlower(user);
 276         dos_to_unix(user);
 277
 278         ret = uname_string_combinations(user, _Get_Pwnam, usernamelevel);
 279
 280         if (ret)
 281                 return(ret);
 282
 283         return(NULL);
 284 }
 285
 286 /****************************************************************************
 287  Check if a user is in a netgroup user list.
 288 ****************************************************************************/
 289
 290 static BOOL user_in_netgroup_list(char *user,char *ngname)
 291 {
 292 #ifdef HAVE_NETGROUP
 293         static char *mydomain = NULL;
 294         if (mydomain == NULL)
 295                 yp_get_default_domain(&mydomain);
 296
 297         if(mydomain == NULL) {
 298                 DEBUG(5,("Unable to get default yp domain\n"));
 299                 return False;
 300         }
 301
 302         DEBUG(5,("looking for user %s of domain %s in netgroup %s\n",
 303                 user, mydomain, ngname));
 304         DEBUG(5,("innetgr is %s\n", innetgr(ngname, NULL, user, mydomain)
 305                 ? "True" : "False"));
 306
 307         if (innetgr(ngname, NULL, user, mydomain))
 308                 return (True);
 309 #endif /* HAVE_NETGROUP */
 310         return False;
 311 }
 312
 313 /****************************************************************************
 314  Check if a user is in a winbind group.
 315 ****************************************************************************/
 316
 317 static BOOL user_in_winbind_group_list(char *user,char *gname, BOOL *winbind_answered)
 318 {
 319         int num_groups;
 320         int i;
 321         gid_t *groups = NULL;
 322         gid_t gid;
 323         BOOL ret = False;
 324
 325         *winbind_answered = False;
 326
 327         /*
 328          * Get the gid's that this user belongs to.
 329          */
 330
 331         if ((num_groups = winbind_getgroups(user, 0, NULL)) == -1)
 332                 return False;
 333
 334         if (num_groups == 0) {
 335                 *winbind_answered = True;
 336                 return False;
 337         }
 338
 339         if ((groups = (gid_t *)malloc(sizeof(gid_t) * num_groups )) == NULL) {
 340                 DEBUG(0,("user_in_winbind_group_list: malloc fail.\n"));
 341                 goto err;
 342         }
 343
 344         if ((num_groups = winbind_getgroups(user, num_groups, groups)) == -1) {
 345                 DEBUG(0,("user_in_winbind_group_list: second winbind_getgroups call \
 346 failed with error %s\n", strerror(errno) ));
 347                 goto err;
 348         }
 349
 350         /*
 351          * Now we have the gid list for this user - convert the gname
 352          * to a gid_t via either winbind or the local UNIX lookup and do the comparison.
 353          */
 354
 355         if ((gid = nametogid(gname)) == (gid_t)-1) {
 356                 DEBUG(0,("user_in_winbind_group_list: winbind_lookup_name for group %s failed.\n",
 357                         gname ));
 358                 goto err;
 359         }
 360
 361         for (i = 0; i < num_groups; i++) {
 362                 if (gid == groups[i]) {
 363                         ret = True;
 364                         break;
 365                 }
 366         }
 367
 368         *winbind_answered = True;
 369         SAFE_FREE(groups);
 370         return ret;
 371
 372    err:
 373
 374         *winbind_answered = False;
 375         SAFE_FREE(groups);
 376         return False;
 377 }
 378
 379 /****************************************************************************
 380  Check if a user is in a UNIX group.
 381 ****************************************************************************/
 382
 383 static BOOL user_in_unix_group_list(char *user,const char *gname)
 384 {
 385         struct passwd *pass = Get_Pwnam(user,False);
 386         struct sys_userlist *user_list;
 387         struct sys_userlist *member;
 388
 389         DEBUG(10,("user_in_unix_group_list: checking user %s in group %s\n", user, gname));
 390
 391         /*
 392          * We need to check the users primary group as this
 393          * group is implicit and often not listed in the group database.
 394          */
 395
 396         if (pass) {
 397                 if (strequal(gname, gidtoname(pass->pw_gid))) {
 398                         DEBUG(10,("user_in_unix_group_list: group %s is primary group.\n", gname ));
 399                         return True;
 400                 }
 401         }
 402
 403         user_list = get_users_in_group(gname);
 404         if (user_list == NULL) {
 405                 DEBUG(10,("user_in_unix_group_list: no such group %s\n", gname ));
 406                 return False;
 407         }
 408
 409         for (member = user_list; member; member = member->next) {
 410                 DEBUG(10,("user_in_unix_group_list: checking user %s against member %s\n",
 411                         user, member->unix_name ));
 412                 if (strequal(member->unix_name,user)) {
 413                         free_userlist(user_list);
 414                         return(True);
 415                 }
 416         }
 417
 418         free_userlist(user_list);
 419         return False;
 420 }
 421
 422 /****************************************************************************
 423  Check if a user is in a group list. Ask winbind first, then use UNIX.
 424 ****************************************************************************/
 425
 426 BOOL user_in_group_list(char *user,char *gname)
 427 {
 428         BOOL winbind_answered = False;
 429         BOOL ret;
 430
 431         ret = user_in_winbind_group_list(user, gname, &winbind_answered);
 432         if (!winbind_answered)
 433                 ret = user_in_unix_group_list(user, gname);
 434
 435         if (ret)
 436                 DEBUG(10,("user_in_group_list: user |%s| is in group |%s|\n", user, gname));
 437         return ret;
 438 }
 439
 440 /****************************************************************************
 441  Check if a user is in a user list - can check combinations of UNIX
 442  and netgroup lists.
 443 ****************************************************************************/
 444
 445 BOOL user_in_list(char *user,char *list)
 446 {
 447         pstring tok;
 448         char *p=list;
 449
 450         DEBUG(10,("user_in_list: checking user %s in list %s\n", user, list));
 451
 452         while (next_token(&p,tok,LIST_SEP, sizeof(tok))) {
 453
 454                 DEBUG(10,("user_in_list: checking user |%s| against |%s|\n", user, tok));
 455
 456                 /*
 457                  * Check raw username.
 458                  */
 459                 if (strequal(user,tok))
 460                         return(True);
 461
 462                 /*
 463                  * Now check to see if any combination
 464                  * of UNIX and netgroups has been specified.
 465                  */
 466
 467                 if(*tok == '@') {
 468                         /*
 469                          * Old behaviour. Check netgroup list
 470                          * followed by UNIX list.
 471                          */
 472                         if(user_in_netgroup_list(user,&tok[1]))
 473                                 return True;
 474                         if(user_in_group_list(user,&tok[1]))
 475                                 return True;
 476                 } else if (*tok == '+') {
 477
 478                         if(tok[1] == '&') {
 479                                 /*
 480                                  * Search UNIX list followed by netgroup.
 481                                  */
 482                                 if(user_in_group_list(user,&tok[2]))
 483                                         return True;
 484                                 if(user_in_netgroup_list(user,&tok[2]))
 485                                         return True;
 486
 487                         } else {
 488
 489                                 /*
 490                                  * Just search UNIX list.
 491                                  */
 492
 493                                 if(user_in_group_list(user,&tok[1]))
 494                                         return True;
 495                         }
 496
 497                 } else if (*tok == '&') {
 498
 499                         if(tok[1] == '+') {
 500                                 /*
 501                                  * Search netgroup list followed by UNIX list.
 502                                  */
 503                                 if(user_in_netgroup_list(user,&tok[2]))
 504                                         return True;
 505                                 if(user_in_group_list(user,&tok[2]))
 506                                         return True;
 507                         } else {
 508                                 /*
 509                                  * Just search netgroup list.
 510                                  */
 511                                 if(user_in_netgroup_list(user,&tok[1]))
 512                                         return True;
 513                         }
 514                 } else if (!name_is_local(tok)) {
 515                         /*
 516                          * If user name did not match and token is not
 517                          * a unix group and the token has a winbind separator in the
 518                          * name then see if it is a Windows group.
 519                          */
 520
 521                         DOM_SID g_sid;
 522                         enum SID_NAME_USE name_type;
 523                         BOOL winbind_answered = False;
 524                         BOOL ret;
 525
 526                         /* Check to see if name is a Windows group */
 527                         if (winbind_lookup_name(NULL, tok, &g_sid, &name_type) && name_type == SID_NAME_DOM_GRP) {
 528
 529                                 /* Check if user name is in the Windows group */
 530                                 ret = user_in_winbind_group_list(user, tok, &winbind_answered);
 531
 532                                 if (winbind_answered && ret == True) {
 533                                         DEBUG(10,("user_in_list: user |%s| is in group |%s|\n", user, tok));
 534                                         return ret;
 535                                 }
 536                         }
 537                 }
 538         }
 539         return(False);
 540 }
 541
 542 /* The functions below have been taken from password.c and slightly modified */
 543 /****************************************************************************
 544  Apply a function to upper/lower case combinations
 545  of a string and return true if one of them returns true.
 546  Try all combinations with N uppercase letters.
 547  offset is the first char to try and change (start with 0)
 548  it assumes the string starts lowercased
 549 ****************************************************************************/
 550
 551 static struct passwd *uname_string_combinations2(char *s,int offset,struct passwd *(*fn)(char *),int N)
 552 {
 553         ssize_t len = (ssize_t)strlen(s);
 554         int i;
 555         struct passwd *ret;
 556
 557         if (N <= 0 || offset >= len)
 558                 return(fn(s));
 559
 560         for (i=offset;i<(len-(N-1));i++) {
 561                 char c = s[i];
 562                 if (!islower((int)c))
 563                         continue;
 564                 s[i] = toupper(c);
 565                 ret = uname_string_combinations2(s,i+1,fn,N-1);
 566                 if(ret)
 567                         return(ret);
 568                 s[i] = c;
 569         }
 570         return(NULL);
 571 }
 572
 573 /****************************************************************************
 574  Apply a function to upper/lower case combinations
 575  of a string and return true if one of them returns true.
 576  Try all combinations with up to N uppercase letters.
 577  offset is the first char to try and change (start with 0)
 578  it assumes the string starts lowercased
 579 ****************************************************************************/
 580
 581 static struct passwd * uname_string_combinations(char *s,struct passwd * (*fn)(char *),int N)
 582 {
 583         int n;
 584         struct passwd *ret;
 585
 586         for (n=1;n<=N;n++) {
 587                 ret = uname_string_combinations2(s,0,fn,n);
 588                 if(ret)
 589                         return(ret);
 590         }
 591         return(NULL);
 592 }
 593
 594
 595 /****************************************************************************
 596 these wrappers allow appliance mode to work. In appliance mode the username
 597 takes the form DOMAIN/user
 598 ****************************************************************************/
 599 struct passwd *smb_getpwnam(char *user, BOOL allow_change)
 600 {
 601         struct passwd *pw;
 602         char *p;
 603         char *sep;
 604         extern pstring global_myname;
 605
 606         pw = Get_Pwnam(user, allow_change);
 607         if (pw)
 608                 return pw;
 609
 610         /*
 611          * If it is a domain qualified name and it isn't in our password
 612          * database but the domain portion matches our local machine name then
 613          * lookup just the username portion locally.
 614          */
 615
 616         sep = lp_winbind_separator();
 617         p = strchr(user,*sep);
 618         if (p && strncasecmp(global_myname, user, strlen(global_myname))==0)
 619                 return Get_Pwnam(p+1, allow_change);
 620
 621         return NULL;
 622 }