crypto/core_namemap.c

   1 /*
   2  * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include "e_os.h"                /* strcasecmp */
  11 #include "internal/namemap.h"
  12 #include <openssl/lhash.h>
  13 #include "crypto/lhash.h"      /* ossl_lh_strcasehash */
  14 #include "internal/tsan_assist.h"
  15 #include "internal/sizes.h"
  16
  17 /*-
  18  * The namenum entry
  19  * =================
  20  */
  21 typedef struct {
  22     char *name;
  23     int number;
  24 } NAMENUM_ENTRY;
  25
  26 DEFINE_LHASH_OF(NAMENUM_ENTRY);
  27
  28 /*-
  29  * The namemap itself
  30  * ==================
  31  */
  32
  33 struct ossl_namemap_st {
  34     /* Flags */
  35     unsigned int stored:1; /* If 1, it's stored in a library context */
  36
  37     CRYPTO_RWLOCK *lock;
  38     LHASH_OF(NAMENUM_ENTRY) *namenum;  /* Name->number mapping */
  39
  40 #ifdef tsan_ld_acq
  41     TSAN_QUALIFIER int max_number;     /* Current max number TSAN version */
  42 #else
  43     int max_number;                    /* Current max number plain version */
  44 #endif
  45 };
  46
  47 /* LHASH callbacks */
  48
  49 static unsigned long namenum_hash(const NAMENUM_ENTRY *n)
  50 {
  51     return ossl_lh_strcasehash(n->name);
  52 }
  53
  54 static int namenum_cmp(const NAMENUM_ENTRY *a, const NAMENUM_ENTRY *b)
  55 {
  56     return strcasecmp(a->name, b->name);
  57 }
  58
  59 static void namenum_free(NAMENUM_ENTRY *n)
  60 {
  61     if (n != NULL)
  62         OPENSSL_free(n->name);
  63     OPENSSL_free(n);
  64 }
  65
  66 /* OSSL_LIB_CTX_METHOD functions for a namemap stored in a library context */
  67
  68 static void *stored_namemap_new(OSSL_LIB_CTX *libctx)
  69 {
  70     OSSL_NAMEMAP *namemap = ossl_namemap_new();
  71
  72     if (namemap != NULL)
  73         namemap->stored = 1;
  74
  75     return namemap;
  76 }
  77
  78 static void stored_namemap_free(void *vnamemap)
  79 {
  80     OSSL_NAMEMAP *namemap = vnamemap;
  81
  82     if (namemap != NULL) {
  83         /* Pretend it isn't stored, or ossl_namemap_free() will do nothing */
  84         namemap->stored = 0;
  85         ossl_namemap_free(namemap);
  86     }
  87 }
  88
  89 static const OSSL_LIB_CTX_METHOD stored_namemap_method = {
  90     stored_namemap_new,
  91     stored_namemap_free,
  92 };
  93
  94 /*-
  95  * API functions
  96  * =============
  97  */
  98
  99 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
 100 {
 101 #ifdef tsan_ld_acq
 102     /* Have TSAN support */
 103     return namemap == NULL || tsan_load(&namemap->max_number) == 0;
 104 #else
 105     /* No TSAN support */
 106     int rv;
 107
 108     if (namemap == NULL)
 109         return 1;
 110
 111     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 112         return -1;
 113     rv = namemap->max_number == 0;
 114     CRYPTO_THREAD_unlock(namemap->lock);
 115     return rv;
 116 #endif
 117 }
 118
 119 typedef struct doall_names_data_st {
 120     int number;
 121     const char **names;
 122     int found;
 123 } DOALL_NAMES_DATA;
 124
 125 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 126 {
 127     if (namenum->number == data->number)
 128         data->names[data->found++] = namenum->name;
 129 }
 130
 131 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 132
 133 /*
 134  * Call the callback for all names in the namemap with the given number.
 135  * A return value 1 means that the callback was called for all names. A
 136  * return value of 0 means that the callback was not called for any names.
 137  */
 138 int ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 139                              void (*fn)(const char *name, void *data),
 140                              void *data)
 141 {
 142     DOALL_NAMES_DATA cbdata;
 143     size_t num_names;
 144     int i;
 145
 146     cbdata.number = number;
 147     cbdata.found = 0;
 148
 149     /*
 150      * We collect all the names first under a read lock. Subsequently we call
 151      * the user function, so that we're not holding the read lock when in user
 152      * code. This could lead to deadlocks.
 153      */
 154     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 155         return 0;
 156
 157     num_names = lh_NAMENUM_ENTRY_num_items(namemap->namenum);
 158     if (num_names == 0) {
 159         CRYPTO_THREAD_unlock(namemap->lock);
 160         return 0;
 161     }
 162     cbdata.names = OPENSSL_malloc(sizeof(*cbdata.names) * num_names);
 163     if (cbdata.names == NULL) {
 164         CRYPTO_THREAD_unlock(namemap->lock);
 165         return 0;
 166     }
 167     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 168                                             &cbdata);
 169     CRYPTO_THREAD_unlock(namemap->lock);
 170
 171     for (i = 0; i < cbdata.found; i++)
 172         fn(cbdata.names[i], data);
 173
 174     OPENSSL_free(cbdata.names);
 175     return 1;
 176 }
 177
 178 static int namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 179                               const char *name, size_t name_len)
 180 {
 181     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 182
 183     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 184         return 0;
 185     namenum_tmpl.number = 0;
 186     namenum_entry =
 187         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 188     OPENSSL_free(namenum_tmpl.name);
 189     return namenum_entry != NULL ? namenum_entry->number : 0;
 190 }
 191
 192 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 193                             const char *name, size_t name_len)
 194 {
 195     int number;
 196
 197 #ifndef FIPS_MODULE
 198     if (namemap == NULL)
 199         namemap = ossl_namemap_stored(NULL);
 200 #endif
 201
 202     if (namemap == NULL)
 203         return 0;
 204
 205     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 206         return 0;
 207     number = namemap_name2num_n(namemap, name, name_len);
 208     CRYPTO_THREAD_unlock(namemap->lock);
 209
 210     return number;
 211 }
 212
 213 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 214 {
 215     if (name == NULL)
 216         return 0;
 217
 218     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 219 }
 220
 221 struct num2name_data_st {
 222     size_t idx;                  /* Countdown */
 223     const char *name;            /* Result */
 224 };
 225
 226 static void do_num2name(const char *name, void *vdata)
 227 {
 228     struct num2name_data_st *data = vdata;
 229
 230     if (data->idx > 0)
 231         data->idx--;
 232     else if (data->name == NULL)
 233         data->name = name;
 234 }
 235
 236 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 237                                   size_t idx)
 238 {
 239     struct num2name_data_st data;
 240
 241     data.idx = idx;
 242     data.name = NULL;
 243     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 244         return NULL;
 245     return data.name;
 246 }
 247
 248 static int namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 249                               const char *name, size_t name_len)
 250 {
 251     NAMENUM_ENTRY *namenum = NULL;
 252     int tmp_number;
 253
 254     /* If it already exists, we don't add it */
 255     if ((tmp_number = namemap_name2num_n(namemap, name, name_len)) != 0)
 256         return tmp_number;
 257
 258     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 259         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 260         goto err;
 261
 262     namenum->number =
 263         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 264     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 265
 266     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 267         goto err;
 268     return namenum->number;
 269
 270  err:
 271     namenum_free(namenum);
 272     return 0;
 273 }
 274
 275 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 276                             const char *name, size_t name_len)
 277 {
 278     int tmp_number;
 279
 280 #ifndef FIPS_MODULE
 281     if (namemap == NULL)
 282         namemap = ossl_namemap_stored(NULL);
 283 #endif
 284
 285     if (name == NULL || name_len == 0 || namemap == NULL)
 286         return 0;
 287
 288     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 289         return 0;
 290     tmp_number = namemap_add_name_n(namemap, number, name, name_len);
 291     CRYPTO_THREAD_unlock(namemap->lock);
 292     return tmp_number;
 293 }
 294
 295 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name)
 296 {
 297     if (name == NULL)
 298         return 0;
 299
 300     return ossl_namemap_add_name_n(namemap, number, name, strlen(name));
 301 }
 302
 303 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 304                            const char *names, const char separator)
 305 {
 306     const char *p, *q;
 307     size_t l;
 308
 309     /* Check that we have a namemap */
 310     if (!ossl_assert(namemap != NULL)) {
 311         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 312         return 0;
 313     }
 314
 315     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 316         return 0;
 317     /*
 318      * Check that no name is an empty string, and that all names have at
 319      * most one numeric identity together.
 320      */
 321     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 322         int this_number;
 323
 324         if ((q = strchr(p, separator)) == NULL)
 325             l = strlen(p);       /* offset to \0 */
 326         else
 327             l = q - p;           /* offset to the next separator */
 328
 329         this_number = namemap_name2num_n(namemap, p, l);
 330
 331         if (*p == '\0' || *p == separator) {
 332             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 333             goto err;
 334         }
 335         if (number == 0) {
 336             number = this_number;
 337         } else if (this_number != 0 && this_number != number) {
 338             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 339                            "\"%.*s\" has an existing different identity %d (from \"%s\")",
 340                            l, p, this_number, names);
 341             goto err;
 342         }
 343     }
 344
 345     /* Now that we have checked, register all names */
 346     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 347         int this_number;
 348
 349         if ((q = strchr(p, separator)) == NULL)
 350             l = strlen(p);       /* offset to \0 */
 351         else
 352             l = q - p;           /* offset to the next separator */
 353
 354         this_number = namemap_add_name_n(namemap, number, p, l);
 355         if (number == 0) {
 356             number = this_number;
 357         } else if (this_number != number) {
 358             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 359                            "Got number %d when expecting %d",
 360                            this_number, number);
 361             goto err;
 362         }
 363     }
 364
 365     CRYPTO_THREAD_unlock(namemap->lock);
 366     return number;
 367
 368  err:
 369     CRYPTO_THREAD_unlock(namemap->lock);
 370     return 0;
 371 }
 372
 373 /*-
 374  * Pre-population
 375  * ==============
 376  */
 377
 378 #ifndef FIPS_MODULE
 379 #include <openssl/evp.h>
 380
 381 /* Creates an initial namemap with names found in the legacy method db */
 382 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 383                                  void *arg)
 384 {
 385     int num = 0;
 386     ASN1_OBJECT *obj;
 387
 388     if (base_nid != NID_undef) {
 389         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 390         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 391     }
 392
 393     if (nid != NID_undef) {
 394         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 395         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 396         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 397             char txtoid[OSSL_MAX_NAME_SIZE];
 398
 399             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1))
 400                 num = ossl_namemap_add_name(arg, num, txtoid);
 401         }
 402     }
 403     if (pem_name != NULL)
 404         num = ossl_namemap_add_name(arg, num, pem_name);
 405 }
 406
 407 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 408 {
 409     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 410
 411     get_legacy_evp_names(NID_undef, EVP_CIPHER_type(cipher), NULL, arg);
 412 }
 413
 414 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 415 {
 416     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 417
 418     get_legacy_evp_names(0, EVP_MD_type(md), NULL, arg);
 419 }
 420
 421 static void get_legacy_pkey_meth_names(const EVP_PKEY_ASN1_METHOD *ameth,
 422                                        void *arg)
 423 {
 424     int nid = 0, base_nid = 0, flags = 0;
 425     const char *pem_name = NULL;
 426
 427     EVP_PKEY_asn1_get0_info(&nid, &base_nid, &flags, NULL, &pem_name, ameth);
 428     if (nid != NID_undef) {
 429         if ((flags & ASN1_PKEY_ALIAS) == 0) {
 430             switch (nid) {
 431             case EVP_PKEY_DHX:
 432                 /* We know that the name "DHX" is used too */
 433                 get_legacy_evp_names(0, nid, "DHX", arg);
 434                 /* FALLTHRU */
 435             default:
 436                 get_legacy_evp_names(0, nid, pem_name, arg);
 437             }
 438         } else {
 439             /*
 440              * Treat aliases carefully, some of them are undesirable, or
 441              * should not be treated as such for providers.
 442              */
 443
 444             switch (nid) {
 445             case EVP_PKEY_SM2:
 446                 /*
 447                  * SM2 is a separate keytype with providers, not an alias for
 448                  * EC.
 449                  */
 450                 get_legacy_evp_names(0, nid, pem_name, arg);
 451                 break;
 452             default:
 453                 /* Use the short name of the base nid as the common reference */
 454                 get_legacy_evp_names(base_nid, nid, pem_name, arg);
 455             }
 456         }
 457     }
 458 }
 459 #endif
 460
 461 /*-
 462  * Constructors / destructors
 463  * ==========================
 464  */
 465
 466 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx)
 467 {
 468 #ifndef FIPS_MODULE
 469     int nms;
 470 #endif
 471     OSSL_NAMEMAP *namemap =
 472         ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_NAMEMAP_INDEX,
 473                               &stored_namemap_method);
 474
 475     if (namemap == NULL)
 476         return NULL;
 477
 478 #ifndef FIPS_MODULE
 479     nms = ossl_namemap_empty(namemap);
 480     if (nms < 0) {
 481         /*
 482          * Could not get lock to make the count, so maybe internal objects
 483          * weren't added. This seems safest.
 484          */
 485         return NULL;
 486     }
 487     if (nms == 1) {
 488         int i, end;
 489
 490         /* Before pilfering, we make sure the legacy database is populated */
 491         OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
 492                             | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);
 493
 494         OBJ_NAME_do_all(OBJ_NAME_TYPE_CIPHER_METH,
 495                         get_legacy_cipher_names, namemap);
 496         OBJ_NAME_do_all(OBJ_NAME_TYPE_MD_METH,
 497                         get_legacy_md_names, namemap);
 498
 499         /* We also pilfer data from the legacy EVP_PKEY_ASN1_METHODs */
 500         for (i = 0, end = EVP_PKEY_asn1_get_count(); i < end; i++)
 501             get_legacy_pkey_meth_names(EVP_PKEY_asn1_get0(i), namemap);
 502     }
 503 #endif
 504
 505     return namemap;
 506 }
 507
 508 OSSL_NAMEMAP *ossl_namemap_new(void)
 509 {
 510     OSSL_NAMEMAP *namemap;
 511
 512     if ((namemap = OPENSSL_zalloc(sizeof(*namemap))) != NULL
 513         && (namemap->lock = CRYPTO_THREAD_lock_new()) != NULL
 514         && (namemap->namenum =
 515             lh_NAMENUM_ENTRY_new(namenum_hash, namenum_cmp)) != NULL)
 516         return namemap;
 517
 518     ossl_namemap_free(namemap);
 519     return NULL;
 520 }
 521
 522 void ossl_namemap_free(OSSL_NAMEMAP *namemap)
 523 {
 524     if (namemap == NULL || namemap->stored)
 525         return;
 526
 527     lh_NAMENUM_ENTRY_doall(namemap->namenum, namenum_free);
 528     lh_NAMENUM_ENTRY_free(namemap->namenum);
 529
 530     CRYPTO_THREAD_lock_free(namemap->lock);
 531     OPENSSL_free(namemap);
 532 }