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     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 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 static void *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 static void 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 static const OSSL_LIB_CTX_METHOD stored_namemap_method = {
  86     OSSL_LIB_CTX_METHOD_DEFAULT_PRIORITY,
  87     stored_namemap_new,
  88     stored_namemap_free,
  89 };
  90
  91 /*-
  92  * API functions
  93  * =============
  94  */
  95
  96 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
  97 {
  98 #ifdef TSAN_REQUIRES_LOCKING
  99     /* No TSAN support */
 100     int rv;
 101
 102     if (namemap == NULL)
 103         return 1;
 104
 105     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 106         return -1;
 107     rv = namemap->max_number == 0;
 108     CRYPTO_THREAD_unlock(namemap->lock);
 109     return rv;
 110 #else
 111     /* Have TSAN support */
 112     return namemap == NULL || tsan_load(&namemap->max_number) == 0;
 113 #endif
 114 }
 115
 116 typedef struct doall_names_data_st {
 117     int number;
 118     const char **names;
 119     int found;
 120 } DOALL_NAMES_DATA;
 121
 122 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 123 {
 124     if (namenum->number == data->number)
 125         data->names[data->found++] = namenum->name;
 126 }
 127
 128 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 129
 130 /*
 131  * Call the callback for all names in the namemap with the given number.
 132  * A return value 1 means that the callback was called for all names. A
 133  * return value of 0 means that the callback was not called for any names.
 134  */
 135 int ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 136                              void (*fn)(const char *name, void *data),
 137                              void *data)
 138 {
 139     DOALL_NAMES_DATA cbdata;
 140     size_t num_names;
 141     int i;
 142
 143     cbdata.number = number;
 144     cbdata.found = 0;
 145
 146     /*
 147      * We collect all the names first under a read lock. Subsequently we call
 148      * the user function, so that we're not holding the read lock when in user
 149      * code. This could lead to deadlocks.
 150      */
 151     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 152         return 0;
 153
 154     num_names = lh_NAMENUM_ENTRY_num_items(namemap->namenum);
 155     if (num_names == 0) {
 156         CRYPTO_THREAD_unlock(namemap->lock);
 157         return 0;
 158     }
 159     cbdata.names = OPENSSL_malloc(sizeof(*cbdata.names) * num_names);
 160     if (cbdata.names == NULL) {
 161         CRYPTO_THREAD_unlock(namemap->lock);
 162         return 0;
 163     }
 164     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 165                                             &cbdata);
 166     CRYPTO_THREAD_unlock(namemap->lock);
 167
 168     for (i = 0; i < cbdata.found; i++)
 169         fn(cbdata.names[i], data);
 170
 171     OPENSSL_free(cbdata.names);
 172     return 1;
 173 }
 174
 175 static int namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 176                               const char *name, size_t name_len)
 177 {
 178     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 179
 180     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 181         return 0;
 182     namenum_tmpl.number = 0;
 183     namenum_entry =
 184         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 185     OPENSSL_free(namenum_tmpl.name);
 186     return namenum_entry != NULL ? namenum_entry->number : 0;
 187 }
 188
 189 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 190                             const char *name, size_t name_len)
 191 {
 192     int number;
 193
 194 #ifndef FIPS_MODULE
 195     if (namemap == NULL)
 196         namemap = ossl_namemap_stored(NULL);
 197 #endif
 198
 199     if (namemap == NULL)
 200         return 0;
 201
 202     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 203         return 0;
 204     number = namemap_name2num_n(namemap, name, name_len);
 205     CRYPTO_THREAD_unlock(namemap->lock);
 206
 207     return number;
 208 }
 209
 210 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 211 {
 212     if (name == NULL)
 213         return 0;
 214
 215     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 216 }
 217
 218 struct num2name_data_st {
 219     size_t idx;                  /* Countdown */
 220     const char *name;            /* Result */
 221 };
 222
 223 static void do_num2name(const char *name, void *vdata)
 224 {
 225     struct num2name_data_st *data = vdata;
 226
 227     if (data->idx > 0)
 228         data->idx--;
 229     else if (data->name == NULL)
 230         data->name = name;
 231 }
 232
 233 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 234                                   size_t idx)
 235 {
 236     struct num2name_data_st data;
 237
 238     data.idx = idx;
 239     data.name = NULL;
 240     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 241         return NULL;
 242     return data.name;
 243 }
 244
 245 static int namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 246                               const char *name, size_t name_len)
 247 {
 248     NAMENUM_ENTRY *namenum = NULL;
 249     int tmp_number;
 250
 251     /* If it already exists, we don't add it */
 252     if ((tmp_number = namemap_name2num_n(namemap, name, name_len)) != 0)
 253         return tmp_number;
 254
 255     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 256         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 257         goto err;
 258
 259     /* The tsan_counter use here is safe since we're under lock */
 260     namenum->number =
 261         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 262     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 263
 264     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 265         goto err;
 266     return namenum->number;
 267
 268  err:
 269     namenum_free(namenum);
 270     return 0;
 271 }
 272
 273 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 274                             const char *name, size_t name_len)
 275 {
 276     int tmp_number;
 277
 278 #ifndef FIPS_MODULE
 279     if (namemap == NULL)
 280         namemap = ossl_namemap_stored(NULL);
 281 #endif
 282
 283     if (name == NULL || name_len == 0 || namemap == NULL)
 284         return 0;
 285
 286     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 287         return 0;
 288     tmp_number = namemap_add_name_n(namemap, number, name, name_len);
 289     CRYPTO_THREAD_unlock(namemap->lock);
 290     return tmp_number;
 291 }
 292
 293 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name)
 294 {
 295     if (name == NULL)
 296         return 0;
 297
 298     return ossl_namemap_add_name_n(namemap, number, name, strlen(name));
 299 }
 300
 301 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 302                            const char *names, const char separator)
 303 {
 304     const char *p, *q;
 305     size_t l;
 306
 307     /* Check that we have a namemap */
 308     if (!ossl_assert(namemap != NULL)) {
 309         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 310         return 0;
 311     }
 312
 313     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 314         return 0;
 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 = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 320         int this_number;
 321
 322         if ((q = strchr(p, separator)) == NULL)
 323             l = strlen(p);       /* offset to \0 */
 324         else
 325             l = q - p;           /* offset to the next separator */
 326
 327         this_number = namemap_name2num_n(namemap, p, l);
 328
 329         if (*p == '\0' || *p == separator) {
 330             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 331             goto err;
 332         }
 333         if (number == 0) {
 334             number = this_number;
 335         } else if (this_number != 0 && this_number != number) {
 336             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 337                            "\"%.*s\" has an existing different identity %d (from \"%s\")",
 338                            l, p, this_number, names);
 339             goto err;
 340         }
 341     }
 342
 343     /* Now that we have checked, register all names */
 344     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 345         int this_number;
 346
 347         if ((q = strchr(p, separator)) == NULL)
 348             l = strlen(p);       /* offset to \0 */
 349         else
 350             l = q - p;           /* offset to the next separator */
 351
 352         this_number = namemap_add_name_n(namemap, number, p, l);
 353         if (number == 0) {
 354             number = this_number;
 355         } else if (this_number != number) {
 356             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 357                            "Got number %d when expecting %d",
 358                            this_number, number);
 359             goto err;
 360         }
 361     }
 362
 363     CRYPTO_THREAD_unlock(namemap->lock);
 364     return number;
 365
 366  err:
 367     CRYPTO_THREAD_unlock(namemap->lock);
 368     return 0;
 369 }
 370
 371 /*-
 372  * Pre-population
 373  * ==============
 374  */
 375
 376 #ifndef FIPS_MODULE
 377 #include <openssl/evp.h>
 378
 379 /* Creates an initial namemap with names found in the legacy method db */
 380 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 381                                  void *arg)
 382 {
 383     int num = 0;
 384     ASN1_OBJECT *obj;
 385
 386     if (base_nid != NID_undef) {
 387         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 388         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 389     }
 390
 391     if (nid != NID_undef) {
 392         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 393         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 394         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 395             char txtoid[OSSL_MAX_NAME_SIZE];
 396
 397             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1) > 0)
 398                 num = ossl_namemap_add_name(arg, num, txtoid);
 399         }
 400     }
 401     if (pem_name != NULL)
 402         num = ossl_namemap_add_name(arg, num, pem_name);
 403 }
 404
 405 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 406 {
 407     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 408
 409     if (cipher != NULL)
 410         get_legacy_evp_names(NID_undef, EVP_CIPHER_get_type(cipher), NULL, arg);
 411 }
 412
 413 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 414 {
 415     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 416
 417     if (md != NULL)
 418         get_legacy_evp_names(0, EVP_MD_get_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 }