crypto/core_namemap.c

   1 /*
   2  * Copyright 2019-2022 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(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     /*
 141      * We collect all the names first under a read lock. Subsequently we call
 142      * the user function, so that we're not holding the read lock when in user
 143      * code. This could lead to deadlocks.
 144      */
 145     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 146         return 0;
 147
 148     num_names = lh_NAMENUM_ENTRY_num_items(namemap->namenum);
 149     if (num_names == 0) {
 150         CRYPTO_THREAD_unlock(namemap->lock);
 151         return 0;
 152     }
 153     cbdata.names = OPENSSL_malloc(sizeof(*cbdata.names) * num_names);
 154     if (cbdata.names == NULL) {
 155         CRYPTO_THREAD_unlock(namemap->lock);
 156         return 0;
 157     }
 158     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 159                                             &cbdata);
 160     CRYPTO_THREAD_unlock(namemap->lock);
 161
 162     for (i = 0; i < cbdata.found; i++)
 163         fn(cbdata.names[i], data);
 164
 165     OPENSSL_free(cbdata.names);
 166     return 1;
 167 }
 168
 169 static int namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 170                               const char *name, size_t name_len)
 171 {
 172     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 173
 174     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 175         return 0;
 176     namenum_tmpl.number = 0;
 177     namenum_entry =
 178         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 179     OPENSSL_free(namenum_tmpl.name);
 180     return namenum_entry != NULL ? namenum_entry->number : 0;
 181 }
 182
 183 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 184                             const char *name, size_t name_len)
 185 {
 186     int number;
 187
 188 #ifndef FIPS_MODULE
 189     if (namemap == NULL)
 190         namemap = ossl_namemap_stored(NULL);
 191 #endif
 192
 193     if (namemap == NULL)
 194         return 0;
 195
 196     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 197         return 0;
 198     number = namemap_name2num_n(namemap, name, name_len);
 199     CRYPTO_THREAD_unlock(namemap->lock);
 200
 201     return number;
 202 }
 203
 204 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 205 {
 206     if (name == NULL)
 207         return 0;
 208
 209     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 210 }
 211
 212 struct num2name_data_st {
 213     size_t idx;                  /* Countdown */
 214     const char *name;            /* Result */
 215 };
 216
 217 static void do_num2name(const char *name, void *vdata)
 218 {
 219     struct num2name_data_st *data = vdata;
 220
 221     if (data->idx > 0)
 222         data->idx--;
 223     else if (data->name == NULL)
 224         data->name = name;
 225 }
 226
 227 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 228                                   size_t idx)
 229 {
 230     struct num2name_data_st data;
 231
 232     data.idx = idx;
 233     data.name = NULL;
 234     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 235         return NULL;
 236     return data.name;
 237 }
 238
 239 static int namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 240                               const char *name, size_t name_len)
 241 {
 242     NAMENUM_ENTRY *namenum = NULL;
 243     int tmp_number;
 244
 245     /* If it already exists, we don't add it */
 246     if ((tmp_number = namemap_name2num_n(namemap, name, name_len)) != 0)
 247         return tmp_number;
 248
 249     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 250         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 251         goto err;
 252
 253     /* The tsan_counter use here is safe since we're under lock */
 254     namenum->number =
 255         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 256     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 257
 258     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 259         goto err;
 260     return namenum->number;
 261
 262  err:
 263     namenum_free(namenum);
 264     return 0;
 265 }
 266
 267 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 268                             const char *name, size_t name_len)
 269 {
 270     int tmp_number;
 271
 272 #ifndef FIPS_MODULE
 273     if (namemap == NULL)
 274         namemap = ossl_namemap_stored(NULL);
 275 #endif
 276
 277     if (name == NULL || name_len == 0 || namemap == NULL)
 278         return 0;
 279
 280     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 281         return 0;
 282     tmp_number = namemap_add_name_n(namemap, number, name, name_len);
 283     CRYPTO_THREAD_unlock(namemap->lock);
 284     return tmp_number;
 285 }
 286
 287 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name)
 288 {
 289     if (name == NULL)
 290         return 0;
 291
 292     return ossl_namemap_add_name_n(namemap, number, name, strlen(name));
 293 }
 294
 295 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 296                            const char *names, const char separator)
 297 {
 298     const char *p, *q;
 299     size_t l;
 300
 301     /* Check that we have a namemap */
 302     if (!ossl_assert(namemap != NULL)) {
 303         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 304         return 0;
 305     }
 306
 307     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 308         return 0;
 309     /*
 310      * Check that no name is an empty string, and that all names have at
 311      * most one numeric identity together.
 312      */
 313     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 314         int this_number;
 315
 316         if ((q = strchr(p, separator)) == NULL)
 317             l = strlen(p);       /* offset to \0 */
 318         else
 319             l = q - p;           /* offset to the next separator */
 320
 321         this_number = namemap_name2num_n(namemap, p, l);
 322
 323         if (*p == '\0' || *p == separator) {
 324             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 325             goto err;
 326         }
 327         if (number == 0) {
 328             number = this_number;
 329         } else if (this_number != 0 && this_number != number) {
 330             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 331                            "\"%.*s\" has an existing different identity %d (from \"%s\")",
 332                            l, p, this_number, names);
 333             goto err;
 334         }
 335     }
 336
 337     /* Now that we have checked, register all names */
 338     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 339         int this_number;
 340
 341         if ((q = strchr(p, separator)) == NULL)
 342             l = strlen(p);       /* offset to \0 */
 343         else
 344             l = q - p;           /* offset to the next separator */
 345
 346         this_number = namemap_add_name_n(namemap, number, p, l);
 347         if (number == 0) {
 348             number = this_number;
 349         } else if (this_number != number) {
 350             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 351                            "Got number %d when expecting %d",
 352                            this_number, number);
 353             goto err;
 354         }
 355     }
 356
 357     CRYPTO_THREAD_unlock(namemap->lock);
 358     return number;
 359
 360  err:
 361     CRYPTO_THREAD_unlock(namemap->lock);
 362     return 0;
 363 }
 364
 365 /*-
 366  * Pre-population
 367  * ==============
 368  */
 369
 370 #ifndef FIPS_MODULE
 371 #include <openssl/evp.h>
 372
 373 /* Creates an initial namemap with names found in the legacy method db */
 374 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 375                                  void *arg)
 376 {
 377     int num = 0;
 378     ASN1_OBJECT *obj;
 379
 380     if (base_nid != NID_undef) {
 381         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 382         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 383     }
 384
 385     if (nid != NID_undef) {
 386         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 387         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 388         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 389             char txtoid[OSSL_MAX_NAME_SIZE];
 390
 391             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1) > 0)
 392                 num = ossl_namemap_add_name(arg, num, txtoid);
 393         }
 394     }
 395     if (pem_name != NULL)
 396         num = ossl_namemap_add_name(arg, num, pem_name);
 397 }
 398
 399 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 400 {
 401     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 402
 403     if (cipher != NULL)
 404         get_legacy_evp_names(NID_undef, EVP_CIPHER_get_type(cipher), NULL, arg);
 405 }
 406
 407 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 408 {
 409     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 410
 411     if (md != NULL)
 412         get_legacy_evp_names(0, EVP_MD_get_type(md), NULL, arg);
 413 }
 414
 415 static void get_legacy_pkey_meth_names(const EVP_PKEY_ASN1_METHOD *ameth,
 416                                        void *arg)
 417 {
 418     int nid = 0, base_nid = 0, flags = 0;
 419     const char *pem_name = NULL;
 420
 421     EVP_PKEY_asn1_get0_info(&nid, &base_nid, &flags, NULL, &pem_name, ameth);
 422     if (nid != NID_undef) {
 423         if ((flags & ASN1_PKEY_ALIAS) == 0) {
 424             switch (nid) {
 425             case EVP_PKEY_DHX:
 426                 /* We know that the name "DHX" is used too */
 427                 get_legacy_evp_names(0, nid, "DHX", arg);
 428                 /* FALLTHRU */
 429             default:
 430                 get_legacy_evp_names(0, nid, pem_name, arg);
 431             }
 432         } else {
 433             /*
 434              * Treat aliases carefully, some of them are undesirable, or
 435              * should not be treated as such for providers.
 436              */
 437
 438             switch (nid) {
 439             case EVP_PKEY_SM2:
 440                 /*
 441                  * SM2 is a separate keytype with providers, not an alias for
 442                  * EC.
 443                  */
 444                 get_legacy_evp_names(0, nid, pem_name, arg);
 445                 break;
 446             default:
 447                 /* Use the short name of the base nid as the common reference */
 448                 get_legacy_evp_names(base_nid, nid, pem_name, arg);
 449             }
 450         }
 451     }
 452 }
 453 #endif
 454
 455 /*-
 456  * Constructors / destructors
 457  * ==========================
 458  */
 459
 460 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx)
 461 {
 462 #ifndef FIPS_MODULE
 463     int nms;
 464 #endif
 465     OSSL_NAMEMAP *namemap =
 466         ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_NAMEMAP_INDEX);
 467
 468     if (namemap == NULL)
 469         return NULL;
 470
 471 #ifndef FIPS_MODULE
 472     nms = ossl_namemap_empty(namemap);
 473     if (nms < 0) {
 474         /*
 475          * Could not get lock to make the count, so maybe internal objects
 476          * weren't added. This seems safest.
 477          */
 478         return NULL;
 479     }
 480     if (nms == 1) {
 481         int i, end;
 482
 483         /* Before pilfering, we make sure the legacy database is populated */
 484         OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
 485                             | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);
 486
 487         OBJ_NAME_do_all(OBJ_NAME_TYPE_CIPHER_METH,
 488                         get_legacy_cipher_names, namemap);
 489         OBJ_NAME_do_all(OBJ_NAME_TYPE_MD_METH,
 490                         get_legacy_md_names, namemap);
 491
 492         /* We also pilfer data from the legacy EVP_PKEY_ASN1_METHODs */
 493         for (i = 0, end = EVP_PKEY_asn1_get_count(); i < end; i++)
 494             get_legacy_pkey_meth_names(EVP_PKEY_asn1_get0(i), namemap);
 495     }
 496 #endif
 497
 498     return namemap;
 499 }
 500
 501 OSSL_NAMEMAP *ossl_namemap_new(void)
 502 {
 503     OSSL_NAMEMAP *namemap;
 504
 505     if ((namemap = OPENSSL_zalloc(sizeof(*namemap))) != NULL
 506         && (namemap->lock = CRYPTO_THREAD_lock_new()) != NULL
 507         && (namemap->namenum =
 508             lh_NAMENUM_ENTRY_new(namenum_hash, namenum_cmp)) != NULL)
 509         return namemap;
 510
 511     ossl_namemap_free(namemap);
 512     return NULL;
 513 }
 514
 515 void ossl_namemap_free(OSSL_NAMEMAP *namemap)
 516 {
 517     if (namemap == NULL || namemap->stored)
 518         return;
 519
 520     lh_NAMENUM_ENTRY_doall(namemap->namenum, namenum_free);
 521     lh_NAMENUM_ENTRY_free(namemap->namenum);
 522
 523     CRYPTO_THREAD_lock_free(namemap->lock);
 524     OPENSSL_free(namemap);
 525 }