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 /* This function is not thread safe, the namemap must be locked */
 170 static int namemap_name2num(const OSSL_NAMEMAP *namemap,
 171                             const char *name)
 172 {
 173     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 174
 175     namenum_tmpl.name = (char *)name;
 176     namenum_tmpl.number = 0;
 177     namenum_entry =
 178         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 179     return namenum_entry != NULL ? namenum_entry->number : 0;
 180 }
 181
 182 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 183 {
 184     int number;
 185
 186 #ifndef FIPS_MODULE
 187     if (namemap == NULL)
 188         namemap = ossl_namemap_stored(NULL);
 189 #endif
 190
 191     if (namemap == NULL)
 192         return 0;
 193
 194     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 195         return 0;
 196     number = namemap_name2num(namemap, name);
 197     CRYPTO_THREAD_unlock(namemap->lock);
 198
 199     return number;
 200 }
 201
 202 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 203                             const char *name, size_t name_len)
 204 {
 205     char *tmp;
 206     int ret;
 207
 208     if (name == NULL || (tmp = OPENSSL_strndup(name, name_len)) == NULL)
 209         return 0;
 210
 211     ret = ossl_namemap_name2num(namemap, tmp);
 212     OPENSSL_free(tmp);
 213     return ret;
 214 }
 215
 216 struct num2name_data_st {
 217     size_t idx;                  /* Countdown */
 218     const char *name;            /* Result */
 219 };
 220
 221 static void do_num2name(const char *name, void *vdata)
 222 {
 223     struct num2name_data_st *data = vdata;
 224
 225     if (data->idx > 0)
 226         data->idx--;
 227     else if (data->name == NULL)
 228         data->name = name;
 229 }
 230
 231 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 232                                   size_t idx)
 233 {
 234     struct num2name_data_st data;
 235
 236     data.idx = idx;
 237     data.name = NULL;
 238     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 239         return NULL;
 240     return data.name;
 241 }
 242
 243 /* This function is not thread safe, the namemap must be locked */
 244 static int namemap_add_name(OSSL_NAMEMAP *namemap, int number,
 245                             const char *name)
 246 {
 247     NAMENUM_ENTRY *namenum = NULL;
 248     int tmp_number;
 249
 250     /* If it already exists, we don't add it */
 251     if ((tmp_number = namemap_name2num(namemap, name)) != 0)
 252         return tmp_number;
 253
 254     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL)
 255         return 0;
 256
 257     if ((namenum->name = OPENSSL_strdup(name)) == NULL)
 258         goto err;
 259
 260     /* The tsan_counter use here is safe since we're under lock */
 261     namenum->number =
 262         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 263     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 264
 265     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 266         goto err;
 267     return namenum->number;
 268
 269  err:
 270     namenum_free(namenum);
 271     return 0;
 272 }
 273
 274 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number,
 275                           const char *name)
 276 {
 277     int tmp_number;
 278
 279 #ifndef FIPS_MODULE
 280     if (namemap == NULL)
 281         namemap = ossl_namemap_stored(NULL);
 282 #endif
 283
 284     if (name == NULL || *name == 0 || namemap == NULL)
 285         return 0;
 286
 287     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 288         return 0;
 289     tmp_number = namemap_add_name(namemap, number, name);
 290     CRYPTO_THREAD_unlock(namemap->lock);
 291     return tmp_number;
 292 }
 293
 294 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 295                            const char *names, const char separator)
 296 {
 297     char *tmp, *p, *q, *endp;
 298
 299     /* Check that we have a namemap */
 300     if (!ossl_assert(namemap != NULL)) {
 301         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 302         return 0;
 303     }
 304
 305     if ((tmp = OPENSSL_strdup(names)) == NULL)
 306         return 0;
 307
 308     if (!CRYPTO_THREAD_write_lock(namemap->lock)) {
 309         OPENSSL_free(tmp);
 310         return 0;
 311     }
 312     /*
 313      * Check that no name is an empty string, and that all names have at
 314      * most one numeric identity together.
 315      */
 316     for (p = tmp; *p != '\0'; p = q) {
 317         int this_number;
 318         size_t l;
 319
 320         if ((q = strchr(p, separator)) == NULL) {
 321             l = strlen(p);       /* offset to \0 */
 322             q = p + l;
 323         } else {
 324             l = q - p;           /* offset to the next separator */
 325             *q++ = '\0';
 326         }
 327
 328         if (*p == '\0') {
 329             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 330             number = 0;
 331             goto end;
 332         }
 333
 334         this_number = namemap_name2num(namemap, p);
 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                            p, this_number, names);
 342             number = 0;
 343             goto end;
 344         }
 345     }
 346     endp = p;
 347
 348     /* Now that we have checked, register all names */
 349     for (p = tmp; p < endp; p = q) {
 350         int this_number;
 351
 352         q = p + strlen(p) + 1;
 353
 354         this_number = namemap_add_name(namemap, number, p);
 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             number = 0;
 362             goto end;
 363         }
 364     }
 365
 366  end:
 367     CRYPTO_THREAD_unlock(namemap->lock);
 368     OPENSSL_free(tmp);
 369     return number;
 370 }
 371
 372 /*-
 373  * Pre-population
 374  * ==============
 375  */
 376
 377 #ifndef FIPS_MODULE
 378 #include <openssl/evp.h>
 379
 380 /* Creates an initial namemap with names found in the legacy method db */
 381 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 382                                  void *arg)
 383 {
 384     int num = 0;
 385     ASN1_OBJECT *obj;
 386
 387     if (base_nid != NID_undef) {
 388         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 389         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 390     }
 391
 392     if (nid != NID_undef) {
 393         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 394         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 395         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 396             char txtoid[OSSL_MAX_NAME_SIZE];
 397
 398             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1) > 0)
 399                 num = ossl_namemap_add_name(arg, num, txtoid);
 400         }
 401     }
 402     if (pem_name != NULL)
 403         num = ossl_namemap_add_name(arg, num, pem_name);
 404 }
 405
 406 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 407 {
 408     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 409
 410     if (cipher != NULL)
 411         get_legacy_evp_names(NID_undef, EVP_CIPHER_get_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     if (md != NULL)
 419         get_legacy_evp_names(0, EVP_MD_get_type(md), NULL, arg);
 420 }
 421
 422 static void get_legacy_pkey_meth_names(const EVP_PKEY_ASN1_METHOD *ameth,
 423                                        void *arg)
 424 {
 425     int nid = 0, base_nid = 0, flags = 0;
 426     const char *pem_name = NULL;
 427
 428     EVP_PKEY_asn1_get0_info(&nid, &base_nid, &flags, NULL, &pem_name, ameth);
 429     if (nid != NID_undef) {
 430         if ((flags & ASN1_PKEY_ALIAS) == 0) {
 431             switch (nid) {
 432             case EVP_PKEY_DHX:
 433                 /* We know that the name "DHX" is used too */
 434                 get_legacy_evp_names(0, nid, "DHX", arg);
 435                 /* FALLTHRU */
 436             default:
 437                 get_legacy_evp_names(0, nid, pem_name, arg);
 438             }
 439         } else {
 440             /*
 441              * Treat aliases carefully, some of them are undesirable, or
 442              * should not be treated as such for providers.
 443              */
 444
 445             switch (nid) {
 446             case EVP_PKEY_SM2:
 447                 /*
 448                  * SM2 is a separate keytype with providers, not an alias for
 449                  * EC.
 450                  */
 451                 get_legacy_evp_names(0, nid, pem_name, arg);
 452                 break;
 453             default:
 454                 /* Use the short name of the base nid as the common reference */
 455                 get_legacy_evp_names(base_nid, nid, pem_name, arg);
 456             }
 457         }
 458     }
 459 }
 460 #endif
 461
 462 /*-
 463  * Constructors / destructors
 464  * ==========================
 465  */
 466
 467 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx)
 468 {
 469 #ifndef FIPS_MODULE
 470     int nms;
 471 #endif
 472     OSSL_NAMEMAP *namemap =
 473         ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_NAMEMAP_INDEX);
 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 }