crypto/core_namemap.c

   1 /*
   2  * Copyright 2019-2023 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 "internal/namemap.h"
  11 #include <openssl/lhash.h>
  12 #include "crypto/lhash.h"      /* ossl_lh_strcasehash */
  13 #include "internal/tsan_assist.h"
  14 #include "internal/sizes.h"
  15 #include "crypto/context.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_EX(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     TSAN_QUALIFIER int max_number;     /* Current max number */
  41 };
  42
  43 /* LHASH callbacks */
  44
  45 static unsigned long namenum_hash(const NAMENUM_ENTRY *n)
  46 {
  47     return ossl_lh_strcasehash(n->name);
  48 }
  49
  50 static int namenum_cmp(const NAMENUM_ENTRY *a, const NAMENUM_ENTRY *b)
  51 {
  52     return OPENSSL_strcasecmp(a->name, b->name);
  53 }
  54
  55 static void namenum_free(NAMENUM_ENTRY *n)
  56 {
  57     if (n != NULL)
  58         OPENSSL_free(n->name);
  59     OPENSSL_free(n);
  60 }
  61
  62 /* OSSL_LIB_CTX_METHOD functions for a namemap stored in a library context */
  63
  64 void *ossl_stored_namemap_new(OSSL_LIB_CTX *libctx)
  65 {
  66     OSSL_NAMEMAP *namemap = ossl_namemap_new();
  67
  68     if (namemap != NULL)
  69         namemap->stored = 1;
  70
  71     return namemap;
  72 }
  73
  74 void ossl_stored_namemap_free(void *vnamemap)
  75 {
  76     OSSL_NAMEMAP *namemap = vnamemap;
  77
  78     if (namemap != NULL) {
  79         /* Pretend it isn't stored, or ossl_namemap_free() will do nothing */
  80         namemap->stored = 0;
  81         ossl_namemap_free(namemap);
  82     }
  83 }
  84
  85 /*-
  86  * API functions
  87  * =============
  88  */
  89
  90 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
  91 {
  92 #ifdef TSAN_REQUIRES_LOCKING
  93     /* No TSAN support */
  94     int rv;
  95
  96     if (namemap == NULL)
  97         return 1;
  98
  99     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 100         return -1;
 101     rv = namemap->max_number == 0;
 102     CRYPTO_THREAD_unlock(namemap->lock);
 103     return rv;
 104 #else
 105     /* Have TSAN support */
 106     return namemap == NULL || tsan_load(&namemap->max_number) == 0;
 107 #endif
 108 }
 109
 110 typedef struct doall_names_data_st {
 111     int number;
 112     const char **names;
 113     int found;
 114 } DOALL_NAMES_DATA;
 115
 116 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 117 {
 118     if (namenum->number == data->number)
 119         data->names[data->found++] = namenum->name;
 120 }
 121
 122 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 123
 124 /*
 125  * Call the callback for all names in the namemap with the given number.
 126  * A return value 1 means that the callback was called for all names. A
 127  * return value of 0 means that the callback was not called for any names.
 128  */
 129 int ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 130                              void (*fn)(const char *name, void *data),
 131                              void *data)
 132 {
 133     DOALL_NAMES_DATA cbdata;
 134     size_t num_names;
 135     int i;
 136
 137     cbdata.number = number;
 138     cbdata.found = 0;
 139
 140     if (namemap == NULL)
 141         return 0;
 142
 143     /*
 144      * We collect all the names first under a read lock. Subsequently we call
 145      * the user function, so that we're not holding the read lock when in user
 146      * code. This could lead to deadlocks.
 147      */
 148     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 149         return 0;
 150
 151     num_names = lh_NAMENUM_ENTRY_num_items(namemap->namenum);
 152     if (num_names == 0) {
 153         CRYPTO_THREAD_unlock(namemap->lock);
 154         return 0;
 155     }
 156     cbdata.names = OPENSSL_malloc(sizeof(*cbdata.names) * num_names);
 157     if (cbdata.names == NULL) {
 158         CRYPTO_THREAD_unlock(namemap->lock);
 159         return 0;
 160     }
 161     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 162                                             &cbdata);
 163     CRYPTO_THREAD_unlock(namemap->lock);
 164
 165     for (i = 0; i < cbdata.found; i++)
 166         fn(cbdata.names[i], data);
 167
 168     OPENSSL_free(cbdata.names);
 169     return 1;
 170 }
 171
 172 /* This function is not thread safe, the namemap must be locked */
 173 static int namemap_name2num(const OSSL_NAMEMAP *namemap,
 174                             const char *name)
 175 {
 176     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 177
 178     namenum_tmpl.name = (char *)name;
 179     namenum_tmpl.number = 0;
 180     namenum_entry =
 181         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 182     return namenum_entry != NULL ? namenum_entry->number : 0;
 183 }
 184
 185 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 186 {
 187     int number;
 188
 189 #ifndef FIPS_MODULE
 190     if (namemap == NULL)
 191         namemap = ossl_namemap_stored(NULL);
 192 #endif
 193
 194     if (namemap == NULL)
 195         return 0;
 196
 197     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 198         return 0;
 199     number = namemap_name2num(namemap, name);
 200     CRYPTO_THREAD_unlock(namemap->lock);
 201
 202     return number;
 203 }
 204
 205 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 206                             const char *name, size_t name_len)
 207 {
 208     char *tmp;
 209     int ret;
 210
 211     if (name == NULL || (tmp = OPENSSL_strndup(name, name_len)) == NULL)
 212         return 0;
 213
 214     ret = ossl_namemap_name2num(namemap, tmp);
 215     OPENSSL_free(tmp);
 216     return ret;
 217 }
 218
 219 struct num2name_data_st {
 220     size_t idx;                  /* Countdown */
 221     const char *name;            /* Result */
 222 };
 223
 224 static void do_num2name(const char *name, void *vdata)
 225 {
 226     struct num2name_data_st *data = vdata;
 227
 228     if (data->idx > 0)
 229         data->idx--;
 230     else if (data->name == NULL)
 231         data->name = name;
 232 }
 233
 234 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 235                                   size_t idx)
 236 {
 237     struct num2name_data_st data;
 238
 239     data.idx = idx;
 240     data.name = NULL;
 241     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 242         return NULL;
 243     return data.name;
 244 }
 245
 246 /* This function is not thread safe, the namemap must be locked */
 247 static int namemap_add_name(OSSL_NAMEMAP *namemap, int number,
 248                             const char *name)
 249 {
 250     NAMENUM_ENTRY *namenum = NULL;
 251     int tmp_number;
 252
 253     /* If it already exists, we don't add it */
 254     if ((tmp_number = namemap_name2num(namemap, name)) != 0)
 255         return tmp_number;
 256
 257     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL)
 258         return 0;
 259
 260     if ((namenum->name = OPENSSL_strdup(name)) == NULL)
 261         goto err;
 262
 263     /* The tsan_counter use here is safe since we're under lock */
 264     namenum->number =
 265         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 266     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 267
 268     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 269         goto err;
 270     return namenum->number;
 271
 272  err:
 273     namenum_free(namenum);
 274     return 0;
 275 }
 276
 277 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number,
 278                           const char *name)
 279 {
 280     int tmp_number;
 281
 282 #ifndef FIPS_MODULE
 283     if (namemap == NULL)
 284         namemap = ossl_namemap_stored(NULL);
 285 #endif
 286
 287     if (name == NULL || *name == 0 || namemap == NULL)
 288         return 0;
 289
 290     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 291         return 0;
 292     tmp_number = namemap_add_name(namemap, number, name);
 293     CRYPTO_THREAD_unlock(namemap->lock);
 294     return tmp_number;
 295 }
 296
 297 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 298                            const char *names, const char separator)
 299 {
 300     char *tmp, *p, *q, *endp;
 301
 302     /* Check that we have a namemap */
 303     if (!ossl_assert(namemap != NULL)) {
 304         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 305         return 0;
 306     }
 307
 308     if ((tmp = OPENSSL_strdup(names)) == NULL)
 309         return 0;
 310
 311     if (!CRYPTO_THREAD_write_lock(namemap->lock)) {
 312         OPENSSL_free(tmp);
 313         return 0;
 314     }
 315     /*
 316      * Check that no name is an empty string, and that all names have at
 317      * most one numeric identity together.
 318      */
 319     for (p = tmp; *p != '\0'; p = q) {
 320         int this_number;
 321         size_t l;
 322
 323         if ((q = strchr(p, separator)) == NULL) {
 324             l = strlen(p);       /* offset to \0 */
 325             q = p + l;
 326         } else {
 327             l = q - p;           /* offset to the next separator */
 328             *q++ = '\0';
 329         }
 330
 331         if (*p == '\0') {
 332             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 333             number = 0;
 334             goto end;
 335         }
 336
 337         this_number = namemap_name2num(namemap, p);
 338
 339         if (number == 0) {
 340             number = this_number;
 341         } else if (this_number != 0 && this_number != number) {
 342             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 343                            "\"%s\" has an existing different identity %d (from \"%s\")",
 344                            p, this_number, names);
 345             number = 0;
 346             goto end;
 347         }
 348     }
 349     endp = p;
 350
 351     /* Now that we have checked, register all names */
 352     for (p = tmp; p < endp; p = q) {
 353         int this_number;
 354
 355         q = p + strlen(p) + 1;
 356
 357         this_number = namemap_add_name(namemap, number, p);
 358         if (number == 0) {
 359             number = this_number;
 360         } else if (this_number != number) {
 361             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 362                            "Got number %d when expecting %d",
 363                            this_number, number);
 364             number = 0;
 365             goto end;
 366         }
 367     }
 368
 369  end:
 370     CRYPTO_THREAD_unlock(namemap->lock);
 371     OPENSSL_free(tmp);
 372     return number;
 373 }
 374
 375 /*-
 376  * Pre-population
 377  * ==============
 378  */
 379
 380 #ifndef FIPS_MODULE
 381 #include <openssl/evp.h>
 382
 383 /* Creates an initial namemap with names found in the legacy method db */
 384 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 385                                  void *arg)
 386 {
 387     int num = 0;
 388     ASN1_OBJECT *obj;
 389
 390     if (base_nid != NID_undef) {
 391         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 392         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 393     }
 394
 395     if (nid != NID_undef) {
 396         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 397         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 398         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 399             char txtoid[OSSL_MAX_NAME_SIZE];
 400
 401             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1) > 0)
 402                 num = ossl_namemap_add_name(arg, num, txtoid);
 403         }
 404     }
 405     if (pem_name != NULL)
 406         num = ossl_namemap_add_name(arg, num, pem_name);
 407 }
 408
 409 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 410 {
 411     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 412
 413     if (cipher != NULL)
 414         get_legacy_evp_names(NID_undef, EVP_CIPHER_get_type(cipher), NULL, arg);
 415 }
 416
 417 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 418 {
 419     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 420
 421     if (md != NULL)
 422         get_legacy_evp_names(0, EVP_MD_get_type(md), NULL, arg);
 423 }
 424
 425 static void get_legacy_pkey_meth_names(const EVP_PKEY_ASN1_METHOD *ameth,
 426                                        void *arg)
 427 {
 428     int nid = 0, base_nid = 0, flags = 0;
 429     const char *pem_name = NULL;
 430
 431     EVP_PKEY_asn1_get0_info(&nid, &base_nid, &flags, NULL, &pem_name, ameth);
 432     if (nid != NID_undef) {
 433         if ((flags & ASN1_PKEY_ALIAS) == 0) {
 434             switch (nid) {
 435             case EVP_PKEY_DHX:
 436                 /* We know that the name "DHX" is used too */
 437                 get_legacy_evp_names(0, nid, "DHX", arg);
 438                 /* FALLTHRU */
 439             default:
 440                 get_legacy_evp_names(0, nid, pem_name, arg);
 441             }
 442         } else {
 443             /*
 444              * Treat aliases carefully, some of them are undesirable, or
 445              * should not be treated as such for providers.
 446              */
 447
 448             switch (nid) {
 449             case EVP_PKEY_SM2:
 450                 /*
 451                  * SM2 is a separate keytype with providers, not an alias for
 452                  * EC.
 453                  */
 454                 get_legacy_evp_names(0, nid, pem_name, arg);
 455                 break;
 456             default:
 457                 /* Use the short name of the base nid as the common reference */
 458                 get_legacy_evp_names(base_nid, nid, pem_name, arg);
 459             }
 460         }
 461     }
 462 }
 463 #endif
 464
 465 /*-
 466  * Constructors / destructors
 467  * ==========================
 468  */
 469
 470 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx)
 471 {
 472 #ifndef FIPS_MODULE
 473     int nms;
 474 #endif
 475     OSSL_NAMEMAP *namemap =
 476         ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_NAMEMAP_INDEX);
 477
 478     if (namemap == NULL)
 479         return NULL;
 480
 481 #ifndef FIPS_MODULE
 482     nms = ossl_namemap_empty(namemap);
 483     if (nms < 0) {
 484         /*
 485          * Could not get lock to make the count, so maybe internal objects
 486          * weren't added. This seems safest.
 487          */
 488         return NULL;
 489     }
 490     if (nms == 1) {
 491         int i, end;
 492
 493         /* Before pilfering, we make sure the legacy database is populated */
 494         OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
 495                             | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);
 496
 497         OBJ_NAME_do_all(OBJ_NAME_TYPE_CIPHER_METH,
 498                         get_legacy_cipher_names, namemap);
 499         OBJ_NAME_do_all(OBJ_NAME_TYPE_MD_METH,
 500                         get_legacy_md_names, namemap);
 501
 502         /* We also pilfer data from the legacy EVP_PKEY_ASN1_METHODs */
 503         for (i = 0, end = EVP_PKEY_asn1_get_count(); i < end; i++)
 504             get_legacy_pkey_meth_names(EVP_PKEY_asn1_get0(i), namemap);
 505     }
 506 #endif
 507
 508     return namemap;
 509 }
 510
 511 OSSL_NAMEMAP *ossl_namemap_new(void)
 512 {
 513     OSSL_NAMEMAP *namemap;
 514
 515     if ((namemap = OPENSSL_zalloc(sizeof(*namemap))) != NULL
 516         && (namemap->lock = CRYPTO_THREAD_lock_new()) != NULL
 517         && (namemap->namenum =
 518             lh_NAMENUM_ENTRY_new(namenum_hash, namenum_cmp)) != NULL)
 519         return namemap;
 520
 521     ossl_namemap_free(namemap);
 522     return NULL;
 523 }
 524
 525 void ossl_namemap_free(OSSL_NAMEMAP *namemap)
 526 {
 527     if (namemap == NULL || namemap->stored)
 528         return;
 529
 530     lh_NAMENUM_ENTRY_doall(namemap->namenum, namenum_free);
 531     lh_NAMENUM_ENTRY_free(namemap->namenum);
 532
 533     CRYPTO_THREAD_lock_free(namemap->lock);
 534     OPENSSL_free(namemap);
 535 }