lib/krb5/mcache.c

   1 /*
   2  * Copyright (c) 1997-2004 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Portions Copyright (c) 2009 Apple Inc. All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include "krb5_locl.h"
  37
  38 typedef struct krb5_mcache {
  39     char *name;
  40     unsigned int refcnt;
  41     int dead;
  42     krb5_principal primary_principal;
  43     struct link {
  44         krb5_creds cred;
  45         struct link *next;
  46     } *creds;
  47     struct krb5_mcache *next;
  48     time_t mtime;
  49     krb5_deltat kdc_offset;
  50 } krb5_mcache;
  51
  52 static HEIMDAL_MUTEX mcc_mutex = HEIMDAL_MUTEX_INITIALIZER;
  53 static struct krb5_mcache *mcc_head;
  54
  55 #define MCACHE(X)       ((krb5_mcache *)(X)->data.data)
  56
  57 #define MISDEAD(X)      ((X)->dead)
  58
  59 static const char* KRB5_CALLCONV
  60 mcc_get_name(krb5_context context,
  61              krb5_ccache id)
  62 {
  63     return MCACHE(id)->name;
  64 }
  65
  66 static krb5_mcache * KRB5_CALLCONV
  67 mcc_alloc(const char *name)
  68 {
  69     krb5_mcache *m, *m_c;
  70     int ret = 0;
  71
  72     ALLOC(m, 1);
  73     if(m == NULL)
  74         return NULL;
  75     if(name == NULL)
  76         ret = asprintf(&m->name, "%p", m);
  77     else
  78         m->name = strdup(name);
  79     if(ret < 0 || m->name == NULL) {
  80         free(m);
  81         return NULL;
  82     }
  83     /* check for dups first */
  84     HEIMDAL_MUTEX_lock(&mcc_mutex);
  85     for (m_c = mcc_head; m_c != NULL; m_c = m_c->next)
  86         if (strcmp(m->name, m_c->name) == 0)
  87             break;
  88     if (m_c) {
  89         free(m->name);
  90         free(m);
  91         HEIMDAL_MUTEX_unlock(&mcc_mutex);
  92         return NULL;
  93     }
  94
  95     m->dead = 0;
  96     m->refcnt = 1;
  97     m->primary_principal = NULL;
  98     m->creds = NULL;
  99     m->mtime = time(NULL);
 100     m->kdc_offset = 0;
 101     m->next = mcc_head;
 102     mcc_head = m;
 103     HEIMDAL_MUTEX_unlock(&mcc_mutex);
 104     return m;
 105 }
 106
 107 static krb5_error_code KRB5_CALLCONV
 108 mcc_resolve(krb5_context context, krb5_ccache *id, const char *res)
 109 {
 110     krb5_mcache *m;
 111
 112     HEIMDAL_MUTEX_lock(&mcc_mutex);
 113     for (m = mcc_head; m != NULL; m = m->next)
 114         if (strcmp(m->name, res) == 0)
 115             break;
 116     HEIMDAL_MUTEX_unlock(&mcc_mutex);
 117
 118     if (m != NULL) {
 119         m->refcnt++;
 120         (*id)->data.data = m;
 121         (*id)->data.length = sizeof(*m);
 122         return 0;
 123     }
 124
 125     m = mcc_alloc(res);
 126     if (m == NULL) {
 127         krb5_set_error_message(context, KRB5_CC_NOMEM,
 128                                N_("malloc: out of memory", ""));
 129         return KRB5_CC_NOMEM;
 130     }
 131
 132     (*id)->data.data = m;
 133     (*id)->data.length = sizeof(*m);
 134
 135     return 0;
 136 }
 137
 138
 139 static krb5_error_code KRB5_CALLCONV
 140 mcc_gen_new(krb5_context context, krb5_ccache *id)
 141 {
 142     krb5_mcache *m;
 143
 144     m = mcc_alloc(NULL);
 145
 146     if (m == NULL) {
 147         krb5_set_error_message(context, KRB5_CC_NOMEM,
 148                                N_("malloc: out of memory", ""));
 149         return KRB5_CC_NOMEM;
 150     }
 151
 152     (*id)->data.data = m;
 153     (*id)->data.length = sizeof(*m);
 154
 155     return 0;
 156 }
 157
 158 static krb5_error_code KRB5_CALLCONV
 159 mcc_initialize(krb5_context context,
 160                krb5_ccache id,
 161                krb5_principal primary_principal)
 162 {
 163     krb5_mcache *m = MCACHE(id);
 164     m->dead = 0;
 165     m->mtime = time(NULL);
 166     return krb5_copy_principal (context,
 167                                 primary_principal,
 168                                 &m->primary_principal);
 169 }
 170
 171 static int
 172 mcc_close_internal(krb5_mcache *m)
 173 {
 174     if (--m->refcnt != 0)
 175         return 0;
 176
 177     if (MISDEAD(m)) {
 178         free (m->name);
 179         return 1;
 180     }
 181     return 0;
 182 }
 183
 184 static krb5_error_code KRB5_CALLCONV
 185 mcc_close(krb5_context context,
 186           krb5_ccache id)
 187 {
 188     if (mcc_close_internal(MCACHE(id)))
 189         krb5_data_free(&id->data);
 190     return 0;
 191 }
 192
 193 static krb5_error_code KRB5_CALLCONV
 194 mcc_destroy(krb5_context context,
 195             krb5_ccache id)
 196 {
 197     krb5_mcache **n, *m = MCACHE(id);
 198     struct link *l;
 199
 200     if (m->refcnt == 0)
 201         krb5_abortx(context, "mcc_destroy: refcnt already 0");
 202
 203     if (!MISDEAD(m)) {
 204         /* if this is an active mcache, remove it from the linked
 205            list, and free all data */
 206         HEIMDAL_MUTEX_lock(&mcc_mutex);
 207         for(n = &mcc_head; n && *n; n = &(*n)->next) {
 208             if(m == *n) {
 209                 *n = m->next;
 210                 break;
 211             }
 212         }
 213         HEIMDAL_MUTEX_unlock(&mcc_mutex);
 214         if (m->primary_principal != NULL) {
 215             krb5_free_principal (context, m->primary_principal);
 216             m->primary_principal = NULL;
 217         }
 218         m->dead = 1;
 219
 220         l = m->creds;
 221         while (l != NULL) {
 222             struct link *old;
 223
 224             krb5_free_cred_contents (context, &l->cred);
 225             old = l;
 226             l = l->next;
 227             free (old);
 228         }
 229         m->creds = NULL;
 230     }
 231     return 0;
 232 }
 233
 234 static krb5_error_code KRB5_CALLCONV
 235 mcc_store_cred(krb5_context context,
 236                krb5_ccache id,
 237                krb5_creds *creds)
 238 {
 239     krb5_mcache *m = MCACHE(id);
 240     krb5_error_code ret;
 241     struct link *l;
 242
 243     if (MISDEAD(m))
 244         return ENOENT;
 245
 246     l = malloc (sizeof(*l));
 247     if (l == NULL) {
 248         krb5_set_error_message(context, KRB5_CC_NOMEM,
 249                                N_("malloc: out of memory", ""));
 250         return KRB5_CC_NOMEM;
 251     }
 252     l->next = m->creds;
 253     m->creds = l;
 254     memset (&l->cred, 0, sizeof(l->cred));
 255     ret = krb5_copy_creds_contents (context, creds, &l->cred);
 256     if (ret) {
 257         m->creds = l->next;
 258         free (l);
 259         return ret;
 260     }
 261     m->mtime = time(NULL);
 262     return 0;
 263 }
 264
 265 static krb5_error_code KRB5_CALLCONV
 266 mcc_get_principal(krb5_context context,
 267                   krb5_ccache id,
 268                   krb5_principal *principal)
 269 {
 270     krb5_mcache *m = MCACHE(id);
 271
 272     if (MISDEAD(m) || m->primary_principal == NULL)
 273         return ENOENT;
 274     return krb5_copy_principal (context,
 275                                 m->primary_principal,
 276                                 principal);
 277 }
 278
 279 static krb5_error_code KRB5_CALLCONV
 280 mcc_get_first (krb5_context context,
 281                krb5_ccache id,
 282                krb5_cc_cursor *cursor)
 283 {
 284     krb5_mcache *m = MCACHE(id);
 285
 286     if (MISDEAD(m))
 287         return ENOENT;
 288
 289     *cursor = m->creds;
 290     return 0;
 291 }
 292
 293 static krb5_error_code KRB5_CALLCONV
 294 mcc_get_next (krb5_context context,
 295               krb5_ccache id,
 296               krb5_cc_cursor *cursor,
 297               krb5_creds *creds)
 298 {
 299     krb5_mcache *m = MCACHE(id);
 300     struct link *l;
 301
 302     if (MISDEAD(m))
 303         return ENOENT;
 304
 305     l = *cursor;
 306     if (l != NULL) {
 307         *cursor = l->next;
 308         return krb5_copy_creds_contents (context,
 309                                          &l->cred,
 310                                          creds);
 311     } else
 312         return KRB5_CC_END;
 313 }
 314
 315 static krb5_error_code KRB5_CALLCONV
 316 mcc_end_get (krb5_context context,
 317              krb5_ccache id,
 318              krb5_cc_cursor *cursor)
 319 {
 320     return 0;
 321 }
 322
 323 static krb5_error_code KRB5_CALLCONV
 324 mcc_remove_cred(krb5_context context,
 325                  krb5_ccache id,
 326                  krb5_flags which,
 327                  krb5_creds *mcreds)
 328 {
 329     krb5_mcache *m = MCACHE(id);
 330     struct link **q, *p;
 331     for(q = &m->creds, p = *q; p; p = *q) {
 332         if(krb5_compare_creds(context, which, mcreds, &p->cred)) {
 333             *q = p->next;
 334             krb5_free_cred_contents(context, &p->cred);
 335             free(p);
 336             m->mtime = time(NULL);
 337         } else
 338             q = &p->next;
 339     }
 340     return 0;
 341 }
 342
 343 static krb5_error_code KRB5_CALLCONV
 344 mcc_set_flags(krb5_context context,
 345               krb5_ccache id,
 346               krb5_flags flags)
 347 {
 348     return 0; /* XXX */
 349 }
 350
 351 struct mcache_iter {
 352     krb5_mcache *cache;
 353 };
 354
 355 static krb5_error_code KRB5_CALLCONV
 356 mcc_get_cache_first(krb5_context context, krb5_cc_cursor *cursor)
 357 {
 358     struct mcache_iter *iter;
 359
 360     iter = calloc(1, sizeof(*iter));
 361     if (iter == NULL) {
 362         krb5_set_error_message(context, ENOMEM,
 363                                N_("malloc: out of memory", ""));
 364         return ENOMEM;
 365     }
 366
 367     HEIMDAL_MUTEX_lock(&mcc_mutex);
 368     iter->cache = mcc_head;
 369     if (iter->cache)
 370         iter->cache->refcnt++;
 371     HEIMDAL_MUTEX_unlock(&mcc_mutex);
 372
 373     *cursor = iter;
 374     return 0;
 375 }
 376
 377 static krb5_error_code KRB5_CALLCONV
 378 mcc_get_cache_next(krb5_context context, krb5_cc_cursor cursor, krb5_ccache *id)
 379 {
 380     struct mcache_iter *iter = cursor;
 381     krb5_error_code ret;
 382     krb5_mcache *m;
 383
 384     if (iter->cache == NULL)
 385         return KRB5_CC_END;
 386
 387     HEIMDAL_MUTEX_lock(&mcc_mutex);
 388     m = iter->cache;
 389     if (m->next)
 390         m->next->refcnt++;
 391     iter->cache = m->next;
 392     HEIMDAL_MUTEX_unlock(&mcc_mutex);
 393
 394     ret = _krb5_cc_allocate(context, &krb5_mcc_ops, id);
 395     if (ret)
 396         return ret;
 397
 398     (*id)->data.data = m;
 399     (*id)->data.length = sizeof(*m);
 400
 401     return 0;
 402 }
 403
 404 static krb5_error_code KRB5_CALLCONV
 405 mcc_end_cache_get(krb5_context context, krb5_cc_cursor cursor)
 406 {
 407     struct mcache_iter *iter = cursor;
 408
 409     if (iter->cache)
 410         mcc_close_internal(iter->cache);
 411     iter->cache = NULL;
 412     free(iter);
 413     return 0;
 414 }
 415
 416 static krb5_error_code KRB5_CALLCONV
 417 mcc_move(krb5_context context, krb5_ccache from, krb5_ccache to)
 418 {
 419     krb5_mcache *mfrom = MCACHE(from), *mto = MCACHE(to);
 420     struct link *creds;
 421     krb5_principal principal;
 422     krb5_mcache **n;
 423
 424     HEIMDAL_MUTEX_lock(&mcc_mutex);
 425
 426     /* drop the from cache from the linked list to avoid lookups */
 427     for(n = &mcc_head; n && *n; n = &(*n)->next) {
 428         if(mfrom == *n) {
 429             *n = mfrom->next;
 430             break;
 431         }
 432     }
 433
 434     /* swap creds */
 435     creds = mto->creds;
 436     mto->creds = mfrom->creds;
 437     mfrom->creds = creds;
 438     /* swap principal */
 439     principal = mto->primary_principal;
 440     mto->primary_principal = mfrom->primary_principal;
 441     mfrom->primary_principal = principal;
 442
 443     mto->mtime = mfrom->mtime = time(NULL);
 444
 445     HEIMDAL_MUTEX_unlock(&mcc_mutex);
 446     mcc_destroy(context, from);
 447
 448     return 0;
 449 }
 450
 451 static krb5_error_code KRB5_CALLCONV
 452 mcc_default_name(krb5_context context, char **str)
 453 {
 454     *str = strdup("MEMORY:");
 455     if (*str == NULL) {
 456         krb5_set_error_message(context, ENOMEM,
 457                                N_("malloc: out of memory", ""));
 458         return ENOMEM;
 459     }
 460     return 0;
 461 }
 462
 463 static krb5_error_code KRB5_CALLCONV
 464 mcc_lastchange(krb5_context context, krb5_ccache id, krb5_timestamp *mtime)
 465 {
 466     *mtime = MCACHE(id)->mtime;
 467     return 0;
 468 }
 469
 470 static krb5_error_code KRB5_CALLCONV
 471 mcc_set_kdc_offset(krb5_context context, krb5_ccache id, krb5_deltat kdc_offset)
 472 {
 473     krb5_mcache *m = MCACHE(id);
 474     m->kdc_offset = kdc_offset;
 475     return 0;
 476 }
 477
 478 static krb5_error_code KRB5_CALLCONV
 479 mcc_get_kdc_offset(krb5_context context, krb5_ccache id, krb5_deltat *kdc_offset)
 480 {
 481     krb5_mcache *m = MCACHE(id);
 482     *kdc_offset = m->kdc_offset;
 483     return 0;
 484 }
 485
 486
 487 /**
 488  * Variable containing the MEMORY based credential cache implemention.
 489  *
 490  * @ingroup krb5_ccache
 491  */
 492
 493 KRB5_LIB_VARIABLE const krb5_cc_ops krb5_mcc_ops = {
 494     KRB5_CC_OPS_VERSION,
 495     "MEMORY",
 496     mcc_get_name,
 497     mcc_resolve,
 498     mcc_gen_new,
 499     mcc_initialize,
 500     mcc_destroy,
 501     mcc_close,
 502     mcc_store_cred,
 503     NULL, /* mcc_retrieve */
 504     mcc_get_principal,
 505     mcc_get_first,
 506     mcc_get_next,
 507     mcc_end_get,
 508     mcc_remove_cred,
 509     mcc_set_flags,
 510     NULL,
 511     mcc_get_cache_first,
 512     mcc_get_cache_next,
 513     mcc_end_cache_get,
 514     mcc_move,
 515     mcc_default_name,
 516     NULL,
 517     mcc_lastchange,
 518     mcc_set_kdc_offset,
 519     mcc_get_kdc_offset
 520 };