libcli/security/dom_sid.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Samba utility functions
   4
   5    Copyright (C) Stefan (metze) Metzmacher      2002-2004
   6    Copyright (C) Andrew Tridgell                1992-2004
   7    Copyright (C) Jeremy Allison                 1999
   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 #include "includes.h"
  24 #include "librpc/gen_ndr/security.h"
  25 #include "dom_sid.h"
  26
  27 /*****************************************************************
  28  Compare the auth portion of two sids.
  29 *****************************************************************/
  30
  31 int dom_sid_compare_auth(const struct dom_sid *sid1,
  32                          const struct dom_sid *sid2)
  33 {
  34         int i;
  35
  36         if (sid1 == sid2)
  37                 return 0;
  38         if (!sid1)
  39                 return -1;
  40         if (!sid2)
  41                 return 1;
  42
  43         if (sid1->sid_rev_num != sid2->sid_rev_num)
  44                 return sid1->sid_rev_num - sid2->sid_rev_num;
  45
  46         for (i = 0; i < 6; i++)
  47                 if (sid1->id_auth[i] != sid2->id_auth[i])
  48                         return sid1->id_auth[i] - sid2->id_auth[i];
  49
  50         return 0;
  51 }
  52
  53 /*****************************************************************
  54  Compare two sids.
  55 *****************************************************************/
  56
  57 int dom_sid_compare(const struct dom_sid *sid1, const struct dom_sid *sid2)
  58 {
  59         int i;
  60
  61         if (sid1 == sid2)
  62                 return 0;
  63         if (!sid1)
  64                 return -1;
  65         if (!sid2)
  66                 return 1;
  67
  68         /* Compare most likely different rids, first: i.e start at end */
  69         if (sid1->num_auths != sid2->num_auths)
  70                 return sid1->num_auths - sid2->num_auths;
  71
  72         for (i = sid1->num_auths-1; i >= 0; --i)
  73                 if (sid1->sub_auths[i] != sid2->sub_auths[i])
  74                         return sid1->sub_auths[i] - sid2->sub_auths[i];
  75
  76         return dom_sid_compare_auth(sid1, sid2);
  77 }
  78
  79 /*****************************************************************
  80  Compare two sids.
  81 *****************************************************************/
  82
  83 bool dom_sid_equal(const struct dom_sid *sid1, const struct dom_sid *sid2)
  84 {
  85         return dom_sid_compare(sid1, sid2) == 0;
  86 }
  87
  88 /*****************************************************************
  89  Add a rid to the end of a sid
  90 *****************************************************************/
  91
  92 bool sid_append_rid(struct dom_sid *sid, uint32_t rid)
  93 {
  94         if (sid->num_auths < ARRAY_SIZE(sid->sub_auths)) {
  95                 sid->sub_auths[sid->num_auths++] = rid;
  96                 return true;
  97         }
  98         return false;
  99 }
 100
 101 /*
 102   See if 2 SIDs are in the same domain
 103   this just compares the leading sub-auths
 104 */
 105 int dom_sid_compare_domain(const struct dom_sid *sid1,
 106                            const struct dom_sid *sid2)
 107 {
 108         int n, i;
 109
 110         n = MIN(sid1->num_auths, sid2->num_auths);
 111
 112         for (i = n-1; i >= 0; --i)
 113                 if (sid1->sub_auths[i] != sid2->sub_auths[i])
 114                         return sid1->sub_auths[i] - sid2->sub_auths[i];
 115
 116         return dom_sid_compare_auth(sid1, sid2);
 117 }
 118
 119 /*****************************************************************
 120  Convert a string to a SID. Returns True on success, False on fail.
 121 *****************************************************************/
 122
 123 bool string_to_sid(struct dom_sid *sidout, const char *sidstr)
 124 {
 125         const char *p;
 126         char *q;
 127         /* BIG NOTE: this function only does SIDS where the identauth is not >= 2^32 */
 128         uint32_t conv;
 129
 130         ZERO_STRUCTP(sidout);
 131
 132         if ((sidstr[0] != 'S' && sidstr[0] != 's') || sidstr[1] != '-') {
 133                 goto format_error;
 134         }
 135
 136         /* Get the revision number. */
 137         p = sidstr + 2;
 138
 139         if (!isdigit(*p)) {
 140                 goto format_error;
 141         }
 142
 143         conv = (uint32_t) strtoul(p, &q, 10);
 144         if (!q || (*q != '-')) {
 145                 goto format_error;
 146         }
 147         sidout->sid_rev_num = (uint8_t) conv;
 148         q++;
 149
 150         if (!isdigit(*q)) {
 151                 goto format_error;
 152         }
 153
 154         /* get identauth */
 155         conv = (uint32_t) strtoul(q, &q, 10);
 156         if (!q) {
 157                 goto format_error;
 158         }
 159
 160         /* identauth in decimal should be <  2^32 */
 161         /* NOTE - the conv value is in big-endian format. */
 162         sidout->id_auth[0] = 0;
 163         sidout->id_auth[1] = 0;
 164         sidout->id_auth[2] = (conv & 0xff000000) >> 24;
 165         sidout->id_auth[3] = (conv & 0x00ff0000) >> 16;
 166         sidout->id_auth[4] = (conv & 0x0000ff00) >> 8;
 167         sidout->id_auth[5] = (conv & 0x000000ff);
 168
 169         sidout->num_auths = 0;
 170         if (*q != '-') {
 171                 /* Just id_auth, no subauths */
 172                 return true;
 173         }
 174
 175         q++;
 176
 177         while (true) {
 178                 char *end;
 179
 180                 if (!isdigit(*q)) {
 181                         goto format_error;
 182                 }
 183
 184                 conv = strtoul(q, &end, 10);
 185                 if (end == q) {
 186                         goto format_error;
 187                 }
 188
 189                 if (!sid_append_rid(sidout, conv)) {
 190                         DEBUG(3, ("Too many sid auths in %s\n", sidstr));
 191                         return false;
 192                 }
 193
 194                 q = end;
 195                 if (*q != '-') {
 196                         break;
 197                 }
 198                 q += 1;
 199         }
 200         return true;
 201
 202 format_error:
 203         DEBUG(3, ("string_to_sid: SID %s is not in a valid format\n", sidstr));
 204         return false;
 205 }
 206
 207 bool dom_sid_parse(const char *sidstr, struct dom_sid *ret)
 208 {
 209         return string_to_sid(ret, sidstr);
 210 }
 211
 212 /*
 213   convert a string to a dom_sid, returning a talloc'd dom_sid
 214 */
 215 struct dom_sid *dom_sid_parse_talloc(TALLOC_CTX *mem_ctx, const char *sidstr)
 216 {
 217         struct dom_sid *ret;
 218         ret = talloc(mem_ctx, struct dom_sid);
 219         if (!ret) {
 220                 return NULL;
 221         }
 222         if (!dom_sid_parse(sidstr, ret)) {
 223                 talloc_free(ret);
 224                 return NULL;
 225         }
 226
 227         return ret;
 228 }
 229
 230 /*
 231   convert a string to a dom_sid, returning a talloc'd dom_sid
 232 */
 233 struct dom_sid *dom_sid_parse_length(TALLOC_CTX *mem_ctx, const DATA_BLOB *sid)
 234 {
 235         struct dom_sid *ret;
 236         char *p = talloc_strndup(mem_ctx, (char *)sid->data, sid->length);
 237         if (!p) {
 238                 return NULL;
 239         }
 240         ret = dom_sid_parse_talloc(mem_ctx, p);
 241         talloc_free(p);
 242         return ret;
 243 }
 244
 245 /*
 246   copy a dom_sid structure
 247 */
 248 struct dom_sid *dom_sid_dup(TALLOC_CTX *mem_ctx, const struct dom_sid *dom_sid)
 249 {
 250         struct dom_sid *ret;
 251         int i;
 252
 253         if (!dom_sid) {
 254                 return NULL;
 255         }
 256
 257         ret = talloc(mem_ctx, struct dom_sid);
 258         if (!ret) {
 259                 return NULL;
 260         }
 261
 262         ret->sid_rev_num = dom_sid->sid_rev_num;
 263         ret->id_auth[0] = dom_sid->id_auth[0];
 264         ret->id_auth[1] = dom_sid->id_auth[1];
 265         ret->id_auth[2] = dom_sid->id_auth[2];
 266         ret->id_auth[3] = dom_sid->id_auth[3];
 267         ret->id_auth[4] = dom_sid->id_auth[4];
 268         ret->id_auth[5] = dom_sid->id_auth[5];
 269         ret->num_auths = dom_sid->num_auths;
 270
 271         for (i=0;i<dom_sid->num_auths;i++) {
 272                 ret->sub_auths[i] = dom_sid->sub_auths[i];
 273         }
 274
 275         return ret;
 276 }
 277
 278 /*
 279   add a rid to a domain dom_sid to make a full dom_sid. This function
 280   returns a new sid in the supplied memory context
 281 */
 282 struct dom_sid *dom_sid_add_rid(TALLOC_CTX *mem_ctx,
 283                                 const struct dom_sid *domain_sid,
 284                                 uint32_t rid)
 285 {
 286         struct dom_sid *sid;
 287
 288         sid = dom_sid_dup(mem_ctx, domain_sid);
 289         if (!sid) return NULL;
 290
 291         if (!sid_append_rid(sid, rid)) {
 292                 talloc_free(sid);
 293                 return NULL;
 294         }
 295
 296         return sid;
 297 }
 298
 299 /*
 300   Split up a SID into its domain and RID part
 301 */
 302 NTSTATUS dom_sid_split_rid(TALLOC_CTX *mem_ctx, const struct dom_sid *sid,
 303                            struct dom_sid **domain, uint32_t *rid)
 304 {
 305         if (sid->num_auths == 0) {
 306                 return NT_STATUS_INVALID_PARAMETER;
 307         }
 308
 309         if (domain) {
 310                 if (!(*domain = dom_sid_dup(mem_ctx, sid))) {
 311                         return NT_STATUS_NO_MEMORY;
 312                 }
 313
 314                 (*domain)->num_auths -= 1;
 315         }
 316
 317         if (rid) {
 318                 *rid = sid->sub_auths[sid->num_auths - 1];
 319         }
 320
 321         return NT_STATUS_OK;
 322 }
 323
 324 /*
 325   return true if the 2nd sid is in the domain given by the first sid
 326 */
 327 bool dom_sid_in_domain(const struct dom_sid *domain_sid,
 328                        const struct dom_sid *sid)
 329 {
 330         int i;
 331
 332         if (!domain_sid || !sid) {
 333                 return false;
 334         }
 335
 336         if (domain_sid->num_auths > sid->num_auths) {
 337                 return false;
 338         }
 339
 340         for (i = domain_sid->num_auths-1; i >= 0; --i) {
 341                 if (domain_sid->sub_auths[i] != sid->sub_auths[i]) {
 342                         return false;
 343                 }
 344         }
 345
 346         return dom_sid_compare_auth(domain_sid, sid) == 0;
 347 }
 348
 349 /*
 350   Convert a dom_sid to a string, printing into a buffer. Return the
 351   string length. If it overflows, return the string length that would
 352   result (buflen needs to be +1 for the terminating 0).
 353 */
 354 int dom_sid_string_buf(const struct dom_sid *sid, char *buf, int buflen)
 355 {
 356         int i, ofs;
 357         uint32_t ia;
 358
 359         if (!sid) {
 360                 strlcpy(buf, "(NULL SID)", buflen);
 361                 return 10;      /* strlen("(NULL SID)") */
 362         }
 363
 364         ia = (sid->id_auth[5]) +
 365                 (sid->id_auth[4] << 8 ) +
 366                 (sid->id_auth[3] << 16) +
 367                 (sid->id_auth[2] << 24);
 368
 369         ofs = snprintf(buf, buflen, "S-%u-%lu",
 370                        (unsigned int)sid->sid_rev_num, (unsigned long)ia);
 371
 372         for (i = 0; i < sid->num_auths; i++) {
 373                 ofs += snprintf(buf + ofs, MAX(buflen - ofs, 0), "-%lu",
 374                                 (unsigned long)sid->sub_auths[i]);
 375         }
 376         return ofs;
 377 }
 378
 379 /*
 380   convert a dom_sid to a string
 381 */
 382 char *dom_sid_string(TALLOC_CTX *mem_ctx, const struct dom_sid *sid)
 383 {
 384         char buf[DOM_SID_STR_BUFLEN];
 385         char *result;
 386         int len;
 387
 388         len = dom_sid_string_buf(sid, buf, sizeof(buf));
 389
 390         if (len+1 > sizeof(buf)) {
 391                 return talloc_strdup(mem_ctx, "(SID ERR)");
 392         }
 393
 394         /*
 395          * Avoid calling strlen (via talloc_strdup), we already have
 396          * the length
 397          */
 398         result = (char *)talloc_memdup(mem_ctx, buf, len+1);
 399
 400         /*
 401          * beautify the talloc_report output
 402          */
 403         talloc_set_name_const(result, result);
 404         return result;
 405 }