crypto/dist/heimdal/kcm/cache.c

   1 /*
   2  * Copyright (c) 2005, PADL Software Pty Ltd.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. Neither the name of PADL Software nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY PADL SOFTWARE AND CONTRIBUTORS ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL PADL SOFTWARE OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "kcm_locl.h"
  34
  35 __RCSID("$Heimdal: cache.c 14566 2005-02-06 01:22:49Z lukeh $"
  36         "$NetBSD$");
  37
  38 static HEIMDAL_MUTEX ccache_mutex = HEIMDAL_MUTEX_INITIALIZER;
  39 static kcm_ccache_data *ccache_head = NULL;
  40 static unsigned int ccache_nextid = 0;
  41
  42 char *kcm_ccache_nextid(pid_t pid, uid_t uid, gid_t gid)
  43 {
  44     unsigned n;
  45     char *name;
  46
  47     HEIMDAL_MUTEX_lock(&ccache_mutex);
  48     n = ++ccache_nextid;
  49     HEIMDAL_MUTEX_unlock(&ccache_mutex);
  50
  51     asprintf(&name, "%d:%u", uid, n);
  52
  53     return name;
  54 }
  55
  56 static krb5_error_code
  57 kcm_ccache_resolve_internal(krb5_context context,
  58                             const char *name,
  59                             kcm_ccache *ccache)
  60 {
  61     kcm_ccache p;
  62     krb5_error_code ret;
  63
  64     *ccache = NULL;
  65
  66     ret = KRB5_FCC_NOFILE;
  67
  68     HEIMDAL_MUTEX_lock(&ccache_mutex);
  69
  70     for (p = ccache_head; p != NULL; p = p->next) {
  71         if ((p->flags & KCM_FLAGS_VALID) == 0)
  72             continue;
  73         if (strcmp(p->name, name) == 0) {
  74             ret = 0;
  75             break;
  76         }
  77     }
  78
  79     if (ret == 0) {
  80         kcm_retain_ccache(context, p);
  81         *ccache = p;
  82     }
  83
  84     HEIMDAL_MUTEX_unlock(&ccache_mutex);
  85
  86     return ret;
  87 }
  88
  89 krb5_error_code kcm_debug_ccache(krb5_context context)
  90 {
  91     kcm_ccache p;
  92
  93     for (p = ccache_head; p != NULL; p = p->next) {
  94         char *cpn = NULL, *spn = NULL;
  95         int ncreds = 0;
  96         struct kcm_creds *k;
  97
  98         if ((p->flags & KCM_FLAGS_VALID) == 0) {
  99             kcm_log(7, "cache %08x: empty slot");
 100             continue;
 101         }
 102
 103         KCM_ASSERT_VALID(p);
 104
 105         for (k = p->creds; k != NULL; k = k->next)
 106             ncreds++;
 107
 108         if (p->client != NULL)
 109             krb5_unparse_name(context, p->client, &cpn);
 110         if (p->server != NULL)
 111             krb5_unparse_name(context, p->server, &spn);
 112
 113         kcm_log(7, "cache %08x: name %s refcnt %d flags %04x mode %04o "
 114                 "uid %d gid %d client %s server %s ncreds %d",
 115                 p, p->name, p->refcnt, p->flags, p->mode, p->uid, p->gid,
 116                 (cpn == NULL) ? "<none>" : cpn,
 117                 (spn == NULL) ? "<none>" : spn,
 118                 ncreds);
 119
 120         if (cpn != NULL)
 121             free(cpn);
 122         if (spn != NULL)
 123             free(spn);
 124     }
 125
 126     return 0;
 127 }
 128
 129 static krb5_error_code
 130 kcm_ccache_destroy_internal(krb5_context context, const char *name)
 131 {
 132     kcm_ccache *p;
 133     krb5_error_code ret;
 134
 135     ret = KRB5_FCC_NOFILE;
 136
 137     HEIMDAL_MUTEX_lock(&ccache_mutex);
 138     for (p = &ccache_head; *p != NULL; p = &(*p)->next) {
 139         if (((*p)->flags & KCM_FLAGS_VALID) == 0)
 140             continue;
 141         if (strcmp((*p)->name, name) == 0) {
 142             ret = 0;
 143             break;
 144         }
 145     }
 146
 147     if (ret)
 148         goto out;
 149
 150     kcm_release_ccache(context, p);
 151
 152 out:
 153     HEIMDAL_MUTEX_unlock(&ccache_mutex);
 154
 155     return ret;
 156 }
 157
 158 static krb5_error_code
 159 kcm_ccache_alloc(krb5_context context,
 160                  const char *name,
 161                  kcm_ccache *ccache)
 162 {
 163     kcm_ccache slot = NULL, p;
 164     krb5_error_code ret;
 165     int new_slot = 0;
 166
 167     *ccache = NULL;
 168
 169     /* First, check for duplicates */
 170     HEIMDAL_MUTEX_lock(&ccache_mutex);
 171     ret = 0;
 172     for (p = ccache_head; p != NULL; p = p->next) {
 173         if (p->flags & KCM_FLAGS_VALID) {
 174             if (strcmp(p->name, name) == 0) {
 175                 ret = KRB5_CC_WRITE;
 176                 break;
 177             }
 178         } else if (slot == NULL)
 179             slot = p;
 180     }
 181
 182     if (ret)
 183         goto out;
 184
 185     /*
 186      * Then try and find an empty slot
 187      * XXX we need to recycle slots for this to actually do anything
 188      */
 189     if (slot == NULL) {
 190         for (; p != NULL; p = p->next) {
 191             if ((p->flags & KCM_FLAGS_VALID) == 0) {
 192                 slot = p;
 193                 break;
 194             }
 195         }
 196
 197         if (slot == NULL) {
 198             slot = (kcm_ccache_data *)malloc(sizeof(*slot));
 199             if (slot == NULL) {
 200                 ret = KRB5_CC_NOMEM;
 201                 goto out;
 202             }
 203             slot->next = ccache_head;
 204             HEIMDAL_MUTEX_init(&slot->mutex);
 205             new_slot = 1;
 206         }
 207     }
 208
 209     slot->name = strdup(name);
 210     if (slot->name == NULL) {
 211         ret = KRB5_CC_NOMEM;
 212         goto out;
 213     }
 214
 215     slot->refcnt = 1;
 216     slot->flags = KCM_FLAGS_VALID;
 217     slot->mode = S_IRUSR | S_IWUSR;
 218     slot->uid = -1;
 219     slot->gid = -1;
 220     slot->client = NULL;
 221     slot->server = NULL;
 222     slot->creds = NULL;
 223     slot->n_cursor = 0;
 224     slot->cursors = NULL;
 225     slot->key.keytab = NULL;
 226     slot->tkt_life = 0;
 227     slot->renew_life = 0;
 228
 229     if (new_slot)
 230         ccache_head = slot;
 231
 232     *ccache = slot;
 233
 234     HEIMDAL_MUTEX_unlock(&ccache_mutex);
 235     return 0;
 236
 237 out:
 238     HEIMDAL_MUTEX_unlock(&ccache_mutex);
 239     if (new_slot && slot != NULL) {
 240         HEIMDAL_MUTEX_destroy(&slot->mutex);
 241         free(slot);
 242     }
 243     return ret;
 244 }
 245
 246 krb5_error_code
 247 kcm_ccache_remove_creds_internal(krb5_context context,
 248                                  kcm_ccache ccache)
 249 {
 250     struct kcm_creds *k;
 251     struct kcm_cursor *c;
 252
 253     k = ccache->creds;
 254     while (k != NULL) {
 255         struct kcm_creds *old;
 256
 257         krb5_free_cred_contents(context, &k->cred);
 258         old = k;
 259         k = k->next;
 260         free(old);
 261     }
 262     ccache->creds = NULL;
 263
 264     /* remove anything that would have pointed into the creds too */
 265
 266     ccache->n_cursor = 0;
 267
 268     c = ccache->cursors;
 269     while (c != NULL) {
 270         struct kcm_cursor *old;
 271
 272         old = c;
 273         c = c->next;
 274         free(old);
 275     }
 276     ccache->cursors = NULL;
 277
 278     return 0;
 279 }
 280
 281 krb5_error_code
 282 kcm_ccache_remove_creds(krb5_context context,
 283                         kcm_ccache ccache)
 284 {
 285     krb5_error_code ret;
 286
 287     KCM_ASSERT_VALID(ccache);
 288
 289     HEIMDAL_MUTEX_lock(&ccache->mutex);
 290     ret = kcm_ccache_remove_creds_internal(context, ccache);
 291     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 292
 293     return ret;
 294 }
 295
 296 krb5_error_code
 297 kcm_zero_ccache_data_internal(krb5_context context,
 298                               kcm_ccache_data *cache)
 299 {
 300     if (cache->client != NULL) {
 301         krb5_free_principal(context, cache->client);
 302         cache->client = NULL;
 303     }
 304
 305     if (cache->server != NULL) {
 306         krb5_free_principal(context, cache->server);
 307         cache->server = NULL;
 308     }
 309
 310     kcm_ccache_remove_creds_internal(context, cache);
 311
 312     return 0;
 313 }
 314
 315 krb5_error_code
 316 kcm_zero_ccache_data(krb5_context context,
 317                      kcm_ccache cache)
 318 {
 319     krb5_error_code ret;
 320
 321     KCM_ASSERT_VALID(cache);
 322
 323     HEIMDAL_MUTEX_lock(&cache->mutex);
 324     ret = kcm_zero_ccache_data_internal(context, cache);
 325     HEIMDAL_MUTEX_unlock(&cache->mutex);
 326
 327     return ret;
 328 }
 329
 330 static krb5_error_code
 331 kcm_free_ccache_data_internal(krb5_context context,
 332                               kcm_ccache_data *cache)
 333 {
 334     KCM_ASSERT_VALID(cache);
 335
 336     if (cache->name != NULL) {
 337         free(cache->name);
 338         cache->name = NULL;
 339     }
 340
 341     if (cache->flags & KCM_FLAGS_USE_KEYTAB) {
 342         krb5_kt_close(context, cache->key.keytab);
 343         cache->key.keytab = NULL;
 344     } else if (cache->flags & KCM_FLAGS_USE_CACHED_KEY) {
 345         krb5_free_keyblock_contents(context, &cache->key.keyblock);
 346         krb5_keyblock_zero(&cache->key.keyblock);
 347     }
 348
 349     cache->flags = 0;
 350     cache->mode = 0;
 351     cache->uid = -1;
 352     cache->gid = -1;
 353
 354     kcm_zero_ccache_data_internal(context, cache);
 355
 356     cache->tkt_life = 0;
 357     cache->renew_life = 0;
 358
 359     cache->next = NULL;
 360     cache->refcnt = 0;
 361
 362     HEIMDAL_MUTEX_unlock(&cache->mutex);
 363     HEIMDAL_MUTEX_destroy(&cache->mutex);
 364
 365     return 0;
 366 }
 367
 368 krb5_error_code
 369 kcm_retain_ccache(krb5_context context,
 370                   kcm_ccache ccache)
 371 {
 372     KCM_ASSERT_VALID(ccache);
 373
 374     HEIMDAL_MUTEX_lock(&ccache->mutex);
 375     ccache->refcnt++;
 376     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 377
 378     return 0;
 379 }
 380
 381 krb5_error_code
 382 kcm_release_ccache(krb5_context context,
 383                    kcm_ccache *ccache)
 384 {
 385     kcm_ccache c = *ccache;
 386     krb5_error_code ret = 0;
 387
 388     KCM_ASSERT_VALID(c);
 389
 390     HEIMDAL_MUTEX_lock(&c->mutex);
 391     if (c->refcnt == 1) {
 392         ret = kcm_free_ccache_data_internal(context, c);
 393         if (ret == 0)
 394             free(c);
 395     } else {
 396         c->refcnt--;
 397         HEIMDAL_MUTEX_unlock(&c->mutex);
 398     }
 399
 400     *ccache = NULL;
 401
 402     return ret;
 403 }
 404
 405 krb5_error_code
 406 kcm_ccache_gen_new(krb5_context context,
 407                    pid_t pid,
 408                    uid_t uid,
 409                    gid_t gid,
 410                    kcm_ccache *ccache)
 411 {
 412     krb5_error_code ret;
 413     char *name;
 414
 415     name = kcm_ccache_nextid(pid, uid, gid);
 416     if (name == NULL) {
 417         return KRB5_CC_NOMEM;
 418     }
 419
 420     ret = kcm_ccache_new(context, name, ccache);
 421
 422     free(name);
 423     return ret;
 424 }
 425
 426 krb5_error_code
 427 kcm_ccache_new(krb5_context context,
 428                const char *name,
 429                kcm_ccache *ccache)
 430 {
 431     krb5_error_code ret;
 432
 433     ret = kcm_ccache_alloc(context, name, ccache);
 434     if (ret == 0) {
 435         /*
 436          * one reference is held by the linked list,
 437          * one by the caller
 438          */
 439         kcm_retain_ccache(context, *ccache);
 440     }
 441
 442     return ret;
 443 }
 444
 445 krb5_error_code
 446 kcm_ccache_resolve(krb5_context context,
 447                    const char *name,
 448                    kcm_ccache *ccache)
 449 {
 450     krb5_error_code ret;
 451
 452     ret = kcm_ccache_resolve_internal(context, name, ccache);
 453
 454     return ret;
 455 }
 456
 457 krb5_error_code
 458 kcm_ccache_destroy(krb5_context context,
 459                    const char *name)
 460 {
 461     krb5_error_code ret;
 462
 463     ret = kcm_ccache_destroy_internal(context, name);
 464
 465     return ret;
 466 }
 467
 468 krb5_error_code
 469 kcm_ccache_destroy_if_empty(krb5_context context,
 470                             kcm_ccache ccache)
 471 {
 472     krb5_error_code ret;
 473
 474     KCM_ASSERT_VALID(ccache);
 475
 476     if (ccache->creds == NULL) {
 477         ret = kcm_ccache_destroy_internal(context, ccache->name);
 478     } else
 479         ret = 0;
 480
 481     return ret;
 482 }
 483
 484 krb5_error_code
 485 kcm_ccache_store_cred(krb5_context context,
 486                       kcm_ccache ccache,
 487                       krb5_creds *creds,
 488                       int copy)
 489 {
 490     krb5_error_code ret;
 491     krb5_creds *tmp;
 492
 493     KCM_ASSERT_VALID(ccache);
 494
 495     HEIMDAL_MUTEX_lock(&ccache->mutex);
 496     ret = kcm_ccache_store_cred_internal(context, ccache, creds, copy, &tmp);
 497     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 498
 499     return ret;
 500 }
 501
 502 krb5_error_code
 503 kcm_ccache_store_cred_internal(krb5_context context,
 504                                kcm_ccache ccache,
 505                                krb5_creds *creds,
 506                                int copy,
 507                                krb5_creds **credp)
 508 {
 509     struct kcm_creds **c;
 510     krb5_error_code ret;
 511
 512     for (c = &ccache->creds; *c != NULL; c = &(*c)->next)
 513         ;
 514
 515     *c = (struct kcm_creds *)malloc(sizeof(struct kcm_creds));
 516     if (*c == NULL) {
 517         return KRB5_CC_NOMEM;
 518     }
 519
 520     *credp = &(*c)->cred;
 521
 522     if (copy) {
 523         ret = krb5_copy_creds_contents(context, creds, *credp);
 524         if (ret) {
 525             free(*c);
 526             *c = NULL;
 527         }
 528     } else {
 529         **credp = *creds;
 530         ret = 0;
 531     }
 532
 533     (*c)->next = NULL;
 534
 535     return ret;
 536 }
 537
 538 static void
 539 remove_cred(krb5_context context,
 540             struct kcm_creds **c)
 541 {
 542     struct kcm_creds *cred;
 543
 544     cred = *c;
 545
 546     *c = cred->next;
 547
 548     krb5_free_cred_contents(context, &cred->cred);
 549     free(cred);
 550 }
 551
 552 krb5_error_code
 553 kcm_ccache_remove_cred_internal(krb5_context context,
 554                                 kcm_ccache ccache,
 555                                 krb5_flags whichfields,
 556                                 const krb5_creds *mcreds)
 557 {
 558     krb5_error_code ret;
 559     struct kcm_creds **c;
 560
 561     ret = KRB5_CC_NOTFOUND;
 562
 563     for (c = &ccache->creds; *c != NULL; c = &(*c)->next) {
 564         if (krb5_compare_creds(context, whichfields, mcreds, &(*c)->cred)) {
 565             remove_cred(context, c);
 566             ret = 0;
 567         }
 568     }
 569
 570     return ret;
 571 }
 572
 573 krb5_error_code
 574 kcm_ccache_remove_cred(krb5_context context,
 575                        kcm_ccache ccache,
 576                        krb5_flags whichfields,
 577                        const krb5_creds *mcreds)
 578 {
 579     krb5_error_code ret;
 580
 581     KCM_ASSERT_VALID(ccache);
 582
 583     HEIMDAL_MUTEX_lock(&ccache->mutex);
 584     ret = kcm_ccache_remove_cred_internal(context, ccache, whichfields, mcreds);
 585     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 586
 587     return ret;
 588 }
 589
 590 krb5_error_code
 591 kcm_ccache_retrieve_cred_internal(krb5_context context,
 592                                   kcm_ccache ccache,
 593                                   krb5_flags whichfields,
 594                                   const krb5_creds *mcreds,
 595                                   krb5_creds **creds)
 596 {
 597     krb5_boolean match;
 598     struct kcm_creds *c;
 599     krb5_error_code ret;
 600
 601     memset(creds, 0, sizeof(*creds));
 602
 603     ret = KRB5_CC_END;
 604
 605     match = FALSE;
 606     for (c = ccache->creds; c != NULL; c = c->next) {
 607         match = krb5_compare_creds(context, whichfields, mcreds, &c->cred);
 608         if (match)
 609             break;
 610     }
 611
 612     if (match) {
 613         ret = 0;
 614         *creds = &c->cred;
 615     }
 616
 617     return ret;
 618 }
 619
 620 krb5_error_code
 621 kcm_ccache_retrieve_cred(krb5_context context,
 622                          kcm_ccache ccache,
 623                          krb5_flags whichfields,
 624                          const krb5_creds *mcreds,
 625                          krb5_creds **credp)
 626 {
 627     krb5_error_code ret;
 628
 629     KCM_ASSERT_VALID(ccache);
 630
 631     HEIMDAL_MUTEX_lock(&ccache->mutex);
 632     ret = kcm_ccache_retrieve_cred_internal(context, ccache,
 633                                             whichfields, mcreds, credp);
 634     HEIMDAL_MUTEX_unlock(&ccache->mutex);
 635
 636     return ret;
 637 }