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 "internal/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 #include "crypto/context.h"
  17
  18 /*-
  19  * The namenum entry
  20  * =================
  21  */
  22 typedef struct {
  23     char *name;
  24     int number;
  25 } NAMENUM_ENTRY;
  26
  27 DEFINE_LHASH_OF(NAMENUM_ENTRY);
  28
  29 /*-
  30  * The namemap itself
  31  * ==================
  32  */
  33
  34 struct ossl_namemap_st {
  35     /* Flags */
  36     unsigned int stored:1; /* If 1, it's stored in a library context */
  37
  38     CRYPTO_RWLOCK *lock;
  39     LHASH_OF(NAMENUM_ENTRY) *namenum;  /* Name->number mapping */
  40
  41     TSAN_QUALIFIER int max_number;     /* Current max number */
  42 };
  43
  44 /* LHASH callbacks */
  45
  46 static unsigned long namenum_hash(const NAMENUM_ENTRY *n)
  47 {
  48     return ossl_lh_strcasehash(n->name);
  49 }
  50
  51 static int namenum_cmp(const NAMENUM_ENTRY *a, const NAMENUM_ENTRY *b)
  52 {
  53     return strcasecmp(a->name, b->name);
  54 }
  55
  56 static void namenum_free(NAMENUM_ENTRY *n)
  57 {
  58     if (n != NULL)
  59         OPENSSL_free(n->name);
  60     OPENSSL_free(n);
  61 }
  62
  63 /* OSSL_LIB_CTX_METHOD functions for a namemap stored in a library context */
  64
  65 void *ossl_stored_namemap_new(OSSL_LIB_CTX *libctx)
  66 {
  67     OSSL_NAMEMAP *namemap = ossl_namemap_new();
  68
  69     if (namemap != NULL)
  70         namemap->stored = 1;
  71
  72     return namemap;
  73 }
  74
  75 void ossl_stored_namemap_free(void *vnamemap)
  76 {
  77     OSSL_NAMEMAP *namemap = vnamemap;
  78
  79     if (namemap != NULL) {
  80         /* Pretend it isn't stored, or ossl_namemap_free() will do nothing */
  81         namemap->stored = 0;
  82         ossl_namemap_free(namemap);
  83     }
  84 }
  85
  86 /*-
  87  * API functions
  88  * =============
  89  */
  90
  91 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
  92 {
  93 #ifdef TSAN_REQUIRES_LOCKING
  94     /* No TSAN support */
  95     int rv;
  96
  97     if (namemap == NULL)
  98         return 1;
  99
 100     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 101         return -1;
 102     rv = namemap->max_number == 0;
 103     CRYPTO_THREAD_unlock(namemap->lock);
 104     return rv;
 105 #else
 106     /* Have TSAN support */
 107     return namemap == NULL || tsan_load(&namemap->max_number) == 0;
 108 #endif
 109 }
 110
 111 typedef struct doall_names_data_st {
 112     int number;
 113     const char **names;
 114     int found;
 115 } DOALL_NAMES_DATA;
 116
 117 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 118 {
 119     if (namenum->number == data->number)
 120         data->names[data->found++] = namenum->name;
 121 }
 122
 123 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 124
 125 /*
 126  * Call the callback for all names in the namemap with the given number.
 127  * A return value 1 means that the callback was called for all names. A
 128  * return value of 0 means that the callback was not called for any names.
 129  */
 130 int ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 131                              void (*fn)(const char *name, void *data),
 132                              void *data)
 133 {
 134     DOALL_NAMES_DATA cbdata;
 135     size_t num_names;
 136     int i;
 137
 138     cbdata.number = number;
 139     cbdata.found = 0;
 140
 141     /*
 142      * We collect all the names first under a read lock. Subsequently we call
 143      * the user function, so that we're not holding the read lock when in user
 144      * code. This could lead to deadlocks.
 145      */
 146     if (!CRYPTO_THREAD_read_lock(namemap->lock))
 147         return 0;
 148
 149     num_names = lh_NAMENUM_ENTRY_num_items(namemap->namenum);
 150     if (num_names == 0) {
 151         CRYPTO_THREAD_unlock(namemap->lock);
 152         return 0;
 153     }
 154     cbdata.names = OPENSSL_malloc(sizeof(*cbdata.names) * num_names);
 155     if (cbdata.names == NULL) {
 156         CRYPTO_THREAD_unlock(namemap->lock);
 157         return 0;
 158     }
 159     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 160                                             &cbdata);
 161     CRYPTO_THREAD_unlock(namemap->lock);
 162
 163     for (i = 0; i < cbdata.found; i++)
 164         fn(cbdata.names[i], data);
 165
 166     OPENSSL_free(cbdata.names);
 167     return 1;
 168 }
 169
 170 static int namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 171                               const char *name, size_t name_len)
 172 {
 173     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 174
 175     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 176         return 0;
 177     namenum_tmpl.number = 0;
 178     namenum_entry =
 179         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 180     OPENSSL_free(namenum_tmpl.name);
 181     return namenum_entry != NULL ? namenum_entry->number : 0;
 182 }
 183
 184 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 185                             const char *name, size_t name_len)
 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_n(namemap, name, name_len);
 200     CRYPTO_THREAD_unlock(namemap->lock);
 201
 202     return number;
 203 }
 204
 205 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 206 {
 207     if (name == NULL)
 208         return 0;
 209
 210     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 211 }
 212
 213 struct num2name_data_st {
 214     size_t idx;                  /* Countdown */
 215     const char *name;            /* Result */
 216 };
 217
 218 static void do_num2name(const char *name, void *vdata)
 219 {
 220     struct num2name_data_st *data = vdata;
 221
 222     if (data->idx > 0)
 223         data->idx--;
 224     else if (data->name == NULL)
 225         data->name = name;
 226 }
 227
 228 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 229                                   size_t idx)
 230 {
 231     struct num2name_data_st data;
 232
 233     data.idx = idx;
 234     data.name = NULL;
 235     if (!ossl_namemap_doall_names(namemap, number, do_num2name, &data))
 236         return NULL;
 237     return data.name;
 238 }
 239
 240 static int namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 241                               const char *name, size_t name_len)
 242 {
 243     NAMENUM_ENTRY *namenum = NULL;
 244     int tmp_number;
 245
 246     /* If it already exists, we don't add it */
 247     if ((tmp_number = namemap_name2num_n(namemap, name, name_len)) != 0)
 248         return tmp_number;
 249
 250     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 251         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 252         goto err;
 253
 254     /* The tsan_counter use here is safe since we're under lock */
 255     namenum->number =
 256         number != 0 ? number : 1 + tsan_counter(&namemap->max_number);
 257     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 258
 259     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 260         goto err;
 261     return namenum->number;
 262
 263  err:
 264     namenum_free(namenum);
 265     return 0;
 266 }
 267
 268 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 269                             const char *name, size_t name_len)
 270 {
 271     int tmp_number;
 272
 273 #ifndef FIPS_MODULE
 274     if (namemap == NULL)
 275         namemap = ossl_namemap_stored(NULL);
 276 #endif
 277
 278     if (name == NULL || name_len == 0 || namemap == NULL)
 279         return 0;
 280
 281     if (!CRYPTO_THREAD_write_lock(namemap->lock))
 282         return 0;
 283     tmp_number = namemap_add_name_n(namemap, number, name, name_len);
 284     CRYPTO_THREAD_unlock(namemap->lock);
 285     return tmp_number;
 286 }
 287
 288 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name)
 289 {
 290     if (name == NULL)
 291         return 0;
 292
 293     return ossl_namemap_add_name_n(namemap, number, name, strlen(name));
 294 }
 295
 296 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 297                            const char *names, const char separator)
 298 {
 299     const char *p, *q;
 300     size_t l;
 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 (!CRYPTO_THREAD_write_lock(namemap->lock))
 309         return 0;
 310     /*
 311      * Check that no name is an empty string, and that all names have at
 312      * most one numeric identity together.
 313      */
 314     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 315         int this_number;
 316
 317         if ((q = strchr(p, separator)) == NULL)
 318             l = strlen(p);       /* offset to \0 */
 319         else
 320             l = q - p;           /* offset to the next separator */
 321
 322         this_number = namemap_name2num_n(namemap, p, l);
 323
 324         if (*p == '\0' || *p == separator) {
 325             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 326             goto err;
 327         }
 328         if (number == 0) {
 329             number = this_number;
 330         } else if (this_number != 0 && this_number != number) {
 331             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 332                            "\"%.*s\" has an existing different identity %d (from \"%s\")",
 333                            l, p, this_number, names);
 334             goto err;
 335         }
 336     }
 337
 338     /* Now that we have checked, register all names */
 339     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 340         int this_number;
 341
 342         if ((q = strchr(p, separator)) == NULL)
 343             l = strlen(p);       /* offset to \0 */
 344         else
 345             l = q - p;           /* offset to the next separator */
 346
 347         this_number = namemap_add_name_n(namemap, number, p, l);
 348         if (number == 0) {
 349             number = this_number;
 350         } else if (this_number != number) {
 351             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 352                            "Got number %d when expecting %d",
 353                            this_number, number);
 354             goto err;
 355         }
 356     }
 357
 358     CRYPTO_THREAD_unlock(namemap->lock);
 359     return number;
 360
 361  err:
 362     CRYPTO_THREAD_unlock(namemap->lock);
 363     return 0;
 364 }
 365
 366 /*-
 367  * Pre-population
 368  * ==============
 369  */
 370
 371 #ifndef FIPS_MODULE
 372 #include <openssl/evp.h>
 373
 374 /* Creates an initial namemap with names found in the legacy method db */
 375 static void get_legacy_evp_names(int base_nid, int nid, const char *pem_name,
 376                                  void *arg)
 377 {
 378     int num = 0;
 379     ASN1_OBJECT *obj;
 380
 381     if (base_nid != NID_undef) {
 382         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(base_nid));
 383         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(base_nid));
 384     }
 385
 386     if (nid != NID_undef) {
 387         num = ossl_namemap_add_name(arg, num, OBJ_nid2sn(nid));
 388         num = ossl_namemap_add_name(arg, num, OBJ_nid2ln(nid));
 389         if ((obj = OBJ_nid2obj(nid)) != NULL) {
 390             char txtoid[OSSL_MAX_NAME_SIZE];
 391
 392             if (OBJ_obj2txt(txtoid, sizeof(txtoid), obj, 1) > 0)
 393                 num = ossl_namemap_add_name(arg, num, txtoid);
 394         }
 395     }
 396     if (pem_name != NULL)
 397         num = ossl_namemap_add_name(arg, num, pem_name);
 398 }
 399
 400 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 401 {
 402     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 403
 404     if (cipher != NULL)
 405         get_legacy_evp_names(NID_undef, EVP_CIPHER_get_type(cipher), NULL, arg);
 406 }
 407
 408 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 409 {
 410     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 411
 412     if (md != NULL)
 413         get_legacy_evp_names(0, EVP_MD_get_type(md), NULL, arg);
 414 }
 415
 416 static void get_legacy_pkey_meth_names(const EVP_PKEY_ASN1_METHOD *ameth,
 417                                        void *arg)
 418 {
 419     int nid = 0, base_nid = 0, flags = 0;
 420     const char *pem_name = NULL;
 421
 422     EVP_PKEY_asn1_get0_info(&nid, &base_nid, &flags, NULL, &pem_name, ameth);
 423     if (nid != NID_undef) {
 424         if ((flags & ASN1_PKEY_ALIAS) == 0) {
 425             switch (nid) {
 426             case EVP_PKEY_DHX:
 427                 /* We know that the name "DHX" is used too */
 428                 get_legacy_evp_names(0, nid, "DHX", arg);
 429                 /* FALLTHRU */
 430             default:
 431                 get_legacy_evp_names(0, nid, pem_name, arg);
 432             }
 433         } else {
 434             /*
 435              * Treat aliases carefully, some of them are undesirable, or
 436              * should not be treated as such for providers.
 437              */
 438
 439             switch (nid) {
 440             case EVP_PKEY_SM2:
 441                 /*
 442                  * SM2 is a separate keytype with providers, not an alias for
 443                  * EC.
 444                  */
 445                 get_legacy_evp_names(0, nid, pem_name, arg);
 446                 break;
 447             default:
 448                 /* Use the short name of the base nid as the common reference */
 449                 get_legacy_evp_names(base_nid, nid, pem_name, arg);
 450             }
 451         }
 452     }
 453 }
 454 #endif
 455
 456 /*-
 457  * Constructors / destructors
 458  * ==========================
 459  */
 460
 461 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx)
 462 {
 463 #ifndef FIPS_MODULE
 464     int nms;
 465 #endif
 466     OSSL_NAMEMAP *namemap =
 467         ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_NAMEMAP_INDEX);
 468
 469     if (namemap == NULL)
 470         return NULL;
 471
 472 #ifndef FIPS_MODULE
 473     nms = ossl_namemap_empty(namemap);
 474     if (nms < 0) {
 475         /*
 476          * Could not get lock to make the count, so maybe internal objects
 477          * weren't added. This seems safest.
 478          */
 479         return NULL;
 480     }
 481     if (nms == 1) {
 482         int i, end;
 483
 484         /* Before pilfering, we make sure the legacy database is populated */
 485         OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
 486                             | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);
 487
 488         OBJ_NAME_do_all(OBJ_NAME_TYPE_CIPHER_METH,
 489                         get_legacy_cipher_names, namemap);
 490         OBJ_NAME_do_all(OBJ_NAME_TYPE_MD_METH,
 491                         get_legacy_md_names, namemap);
 492
 493         /* We also pilfer data from the legacy EVP_PKEY_ASN1_METHODs */
 494         for (i = 0, end = EVP_PKEY_asn1_get_count(); i < end; i++)
 495             get_legacy_pkey_meth_names(EVP_PKEY_asn1_get0(i), namemap);
 496     }
 497 #endif
 498
 499     return namemap;
 500 }
 501
 502 OSSL_NAMEMAP *ossl_namemap_new(void)
 503 {
 504     OSSL_NAMEMAP *namemap;
 505
 506     if ((namemap = OPENSSL_zalloc(sizeof(*namemap))) != NULL
 507         && (namemap->lock = CRYPTO_THREAD_lock_new()) != NULL
 508         && (namemap->namenum =
 509             lh_NAMENUM_ENTRY_new(namenum_hash, namenum_cmp)) != NULL)
 510         return namemap;
 511
 512     ossl_namemap_free(namemap);
 513     return NULL;
 514 }
 515
 516 void ossl_namemap_free(OSSL_NAMEMAP *namemap)
 517 {
 518     if (namemap == NULL || namemap->stored)
 519         return;
 520
 521     lh_NAMENUM_ENTRY_doall(namemap->namenum, namenum_free);
 522     lh_NAMENUM_ENTRY_free(namemap->namenum);
 523
 524     CRYPTO_THREAD_lock_free(namemap->lock);
 525     OPENSSL_free(namemap);
 526 }