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     OSSL_LIB_CTX_METHOD_DEFAULT_PRIORITY,
  91     stored_namemap_new,
  92     stored_namemap_free,
  93 };
  94
  95 /*-
  96  * API functions
  97  * =============
  98  */
  99
 100 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
 101 {
 102 #ifdef tsan_ld_acq
 103     /* Have TSAN support */
 104     return namemap == NULL || tsan_load(&namemap->max_number) == 0;
 105 #else
 106     /* No TSAN support */
 107     int rv;
 108
 109     if (namemap == NULL)
 110         return 1;
 111
 112     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 113         return -1;
 114     rv = namemap->max_number == 0;
 115     CRYPTO_THREAD_unlock(namemap->lock);
 116     return rv;
 117 #endif
 118 }
 119
 120 typedef struct doall_names_data_st {
 121     int number;
 122     const char **names;
 123     int found;
 124 } DOALL_NAMES_DATA;
 125
 126 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 127 {
 128     if (namenum->number == data->number)
 129         data->names[data->found++] = namenum->name;
 130 }
 131
 132 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 133
 134 /*
 135  * Call the callback for all names in the namemap with the given number.
 136  * A return value 1 means that the callback was called for all names. A
 137  * return value of 0 means that the callback was not called for any names.
 138  */
 139 int ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 140                              void (*fn)(const char *name, void *data),
 141                              void *data)
 142 {
 143     DOALL_NAMES_DATA cbdata;
 144     size_t num_names;
 145     int i;
 146
 147     cbdata.number = number;
 148     cbdata.found = 0;
 149
 150     /*
 151      * We collect all the names first under a read lock. Subsequently we call
 152      * the user function, so that we're not holding the read lock when in user
 153      * code. This could lead to deadlocks.
 154      */
 155     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 156         return 0;
 157
 158     num_names = lh_NAMENUM_ENTRY_num_items(namemap->namenum);
 159     if (num_names == 0) {
 160         CRYPTO_THREAD_unlock(namemap->lock);
 161         return 0;
 162     }
 163     cbdata.names = OPENSSL_malloc(sizeof(*cbdata.names) * num_names);
 164     if (cbdata.names == NULL) {
 165         CRYPTO_THREAD_unlock(namemap->lock);
 166         return 0;
 167     }
 168     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 169                                             &cbdata);
 170     CRYPTO_THREAD_unlock(namemap->lock);
 171
 172     for (i = 0; i < cbdata.found; i++)
 173         fn(cbdata.names[i], data);
 174
 175     OPENSSL_free(cbdata.names);
 176     return 1;
 177 }
 178
 179 static int namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 180                               const char *name, size_t name_len)
 181 {
 182     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 183
 184     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 185         return 0;
 186     namenum_tmpl.number = 0;
 187     namenum_entry =
 188         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 189     OPENSSL_free(namenum_tmpl.name);
 190     return namenum_entry != NULL ? namenum_entry->number : 0;
 191 }
 192
 193 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 194                             const char *name, size_t name_len)
 195 {
 196     int number;
 197
 198 #ifndef FIPS_MODULE
 199     if (namemap == NULL)
 200         namemap = ossl_namemap_stored(NULL);
 201 #endif
 202
 203     if (namemap == NULL)
 204         return 0;
 205
 206     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 207         return 0;
 208     number = namemap_name2num_n(namemap, name, name_len);
 209     CRYPTO_THREAD_unlock(namemap->lock);
 210
 211     return number;
 212 }
 213
 214 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 215 {
 216     if (name == NULL)
 217         return 0;
 218
 219     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 220 }
 221
 222 struct num2name_data_st {
 223     size_t idx;                  /* Countdown */
 224     const char *name;            /* Result */
 225 };
 226
 227 static void do_num2name(const char *name, void *vdata)
 228 {
 229     struct num2name_data_st *data = vdata;
 230
 231     if (data->idx > 0)
 232         data->idx--;
 233     else if (data->name == NULL)
 234         data->name = name;
 235 }
 236
 237 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 238                                   size_t idx)
 239 {
 240     struct num2name_data_st data;
 241
 242     data.idx = idx;
 243     data.name = NULL;
 244     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 245         return NULL;
 246     return data.name;
 247 }
 248
 249 static int namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 250                               const char *name, size_t name_len)
 251 {
 252     NAMENUM_ENTRY *namenum = NULL;
 253     int tmp_number;
 254
 255     /* If it already exists, we don't add it */
 256     if ((tmp_number = namemap_name2num_n(namemap, name, name_len)) != 0)
 257         return tmp_number;
 258
 259     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 260         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 261         goto err;
 262
 263     namenum->number =
 264         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 265     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 266
 267     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 268         goto err;
 269     return namenum->number;
 270
 271  err:
 272     namenum_free(namenum);
 273     return 0;
 274 }
 275
 276 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 277                             const char *name, size_t name_len)
 278 {
 279     int tmp_number;
 280
 281 #ifndef FIPS_MODULE
 282     if (namemap == NULL)
 283         namemap = ossl_namemap_stored(NULL);
 284 #endif
 285
 286     if (name == NULL || name_len == 0 || namemap == NULL)
 287         return 0;
 288
 289     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 290         return 0;
 291     tmp_number = namemap_add_name_n(namemap, number, name, name_len);
 292     CRYPTO_THREAD_unlock(namemap->lock);
 293     return tmp_number;
 294 }
 295
 296 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name)
 297 {
 298     if (name == NULL)
 299         return 0;
 300
 301     return ossl_namemap_add_name_n(namemap, number, name, strlen(name));
 302 }
 303
 304 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 305                            const char *names, const char separator)
 306 {
 307     const char *p, *q;
 308     size_t l;
 309
 310     /* Check that we have a namemap */
 311     if (!ossl_assert(namemap != NULL)) {
 312         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 313         return 0;
 314     }
 315
 316     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 317         return 0;
 318     /*
 319      * Check that no name is an empty string, and that all names have at
 320      * most one numeric identity together.
 321      */
 322     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 323         int this_number;
 324
 325         if ((q = strchr(p, separator)) == NULL)
 326             l = strlen(p);       /* offset to \0 */
 327         else
 328             l = q - p;           /* offset to the next separator */
 329
 330         this_number = namemap_name2num_n(namemap, p, l);
 331
 332         if (*p == '\0' || *p == separator) {
 333             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 334             goto err;
 335         }
 336         if (number == 0) {
 337             number = this_number;
 338         } else if (this_number != 0 && this_number != number) {
 339             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 340                            "\"%.*s\" has an existing different identity %d (from \"%s\")",
 341                            l, p, this_number, names);
 342             goto err;
 343         }
 344     }
 345
 346     /* Now that we have checked, register all names */
 347     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 348         int this_number;
 349
 350         if ((q = strchr(p, separator)) == NULL)
 351             l = strlen(p);       /* offset to \0 */
 352         else
 353             l = q - p;           /* offset to the next separator */
 354
 355         this_number = namemap_add_name_n(namemap, number, p, l);
 356         if (number == 0) {
 357             number = this_number;
 358         } else if (this_number != number) {
 359             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 360                            "Got number %d when expecting %d",
 361                            this_number, number);
 362             goto err;
 363         }
 364     }
 365
 366     CRYPTO_THREAD_unlock(namemap->lock);
 367     return number;
 368
 369  err:
 370     CRYPTO_THREAD_unlock(namemap->lock);
 371     return 0;
 372 }
 373
 374 /*-
 375  * Pre-population
 376  * ==============
 377  */
 378
 379 #ifndef FIPS_MODULE
 380 #include <openssl/evp.h>
 381
 382 /* Creates an initial namemap with names found in the legacy method db */
 383 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 384                                  void *arg)
 385 {
 386     int num = 0;
 387     ASN1_OBJECT *obj;
 388
 389     if (base_nid != NID_undef) {
 390         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 391         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 392     }
 393
 394     if (nid != NID_undef) {
 395         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 396         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 397         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 398             char txtoid[OSSL_MAX_NAME_SIZE];
 399
 400             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1) > 0)
 401                 num = ossl_namemap_add_name(arg, num, txtoid);
 402         }
 403     }
 404     if (pem_name != NULL)
 405         num = ossl_namemap_add_name(arg, num, pem_name);
 406 }
 407
 408 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 409 {
 410     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 411
 412     if (cipher != NULL)
 413         get_legacy_evp_names(NID_undef, EVP_CIPHER_get_type(cipher), NULL, arg);
 414 }
 415
 416 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 417 {
 418     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 419
 420     if (md != NULL)
 421         get_legacy_evp_names(0, EVP_MD_get_type(md), NULL, arg);
 422 }
 423
 424 static void get_legacy_pkey_meth_names(const EVP_PKEY_ASN1_METHOD *ameth,
 425                                        void *arg)
 426 {
 427     int nid = 0, base_nid = 0, flags = 0;
 428     const char *pem_name = NULL;
 429
 430     EVP_PKEY_asn1_get0_info(&nid, &base_nid, &flags, NULL, &pem_name, ameth);
 431     if (nid != NID_undef) {
 432         if ((flags & ASN1_PKEY_ALIAS) == 0) {
 433             switch (nid) {
 434             case EVP_PKEY_DHX:
 435                 /* We know that the name "DHX" is used too */
 436                 get_legacy_evp_names(0, nid, "DHX", arg);
 437                 /* FALLTHRU */
 438             default:
 439                 get_legacy_evp_names(0, nid, pem_name, arg);
 440             }
 441         } else {
 442             /*
 443              * Treat aliases carefully, some of them are undesirable, or
 444              * should not be treated as such for providers.
 445              */
 446
 447             switch (nid) {
 448             case EVP_PKEY_SM2:
 449                 /*
 450                  * SM2 is a separate keytype with providers, not an alias for
 451                  * EC.
 452                  */
 453                 get_legacy_evp_names(0, nid, pem_name, arg);
 454                 break;
 455             default:
 456                 /* Use the short name of the base nid as the common reference */
 457                 get_legacy_evp_names(base_nid, nid, pem_name, arg);
 458             }
 459         }
 460     }
 461 }
 462 #endif
 463
 464 /*-
 465  * Constructors / destructors
 466  * ==========================
 467  */
 468
 469 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx)
 470 {
 471 #ifndef FIPS_MODULE
 472     int nms;
 473 #endif
 474     OSSL_NAMEMAP *namemap =
 475         ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_NAMEMAP_INDEX,
 476                               &stored_namemap_method);
 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 }