crypto/core_namemap.c

   1 /*
   2  * Copyright 2019 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"      /* openssl_lh_strcasehash */
  14
  15 /*-
  16  * The namenum entry
  17  * =================
  18  */
  19 typedef struct {
  20     char *name;
  21     int number;
  22 } NAMENUM_ENTRY;
  23
  24 DEFINE_LHASH_OF(NAMENUM_ENTRY);
  25
  26 /*-
  27  * The namemap itself
  28  * ==================
  29  */
  30
  31 struct ossl_namemap_st {
  32     /* Flags */
  33     unsigned int stored:1; /* If 1, it's stored in a library context */
  34
  35     CRYPTO_RWLOCK *lock;
  36     LHASH_OF(NAMENUM_ENTRY) *namenum;  /* Name->number mapping */
  37     int max_number;                    /* Current max number */
  38 };
  39
  40 /* LHASH callbacks */
  41
  42 static unsigned long namenum_hash(const NAMENUM_ENTRY *n)
  43 {
  44     return openssl_lh_strcasehash(n->name);
  45 }
  46
  47 static int namenum_cmp(const NAMENUM_ENTRY *a, const NAMENUM_ENTRY *b)
  48 {
  49     return strcasecmp(a->name, b->name);
  50 }
  51
  52 static void namenum_free(NAMENUM_ENTRY *n)
  53 {
  54     if (n != NULL)
  55         OPENSSL_free(n->name);
  56     OPENSSL_free(n);
  57 }
  58
  59 /* OPENSSL_CTX_METHOD functions for a namemap stored in a library context */
  60
  61 static void *stored_namemap_new(OPENSSL_CTX *libctx)
  62 {
  63     OSSL_NAMEMAP *namemap = ossl_namemap_new();
  64
  65     if (namemap != NULL)
  66         namemap->stored = 1;
  67
  68     return namemap;
  69 }
  70
  71 static void stored_namemap_free(void *vnamemap)
  72 {
  73     OSSL_NAMEMAP *namemap = vnamemap;
  74
  75     if (namemap != NULL) {
  76         /* Pretend it isn't stored, or ossl_namemap_free() will do nothing */
  77         namemap->stored = 0;
  78         ossl_namemap_free(namemap);
  79     }
  80 }
  81
  82 static const OPENSSL_CTX_METHOD stored_namemap_method = {
  83     stored_namemap_new,
  84     stored_namemap_free,
  85 };
  86
  87 /*-
  88  * API functions
  89  * =============
  90  */
  91
  92 int ossl_namemap_empty(OSSL_NAMEMAP *namemap)
  93 {
  94     int rv = 0;
  95
  96     CRYPTO_THREAD_read_lock(namemap->lock);
  97     if (namemap->max_number == 0)
  98         rv = 1;
  99     CRYPTO_THREAD_unlock(namemap->lock);
 100
 101     return rv;
 102 }
 103
 104 typedef struct doall_names_data_st {
 105     int number;
 106     void (*fn)(const char *name, void *data);
 107     void *data;
 108 } DOALL_NAMES_DATA;
 109
 110 static void do_name(const NAMENUM_ENTRY *namenum, DOALL_NAMES_DATA *data)
 111 {
 112     if (namenum->number == data->number)
 113         data->fn(namenum->name, data->data);
 114 }
 115
 116 IMPLEMENT_LHASH_DOALL_ARG_CONST(NAMENUM_ENTRY, DOALL_NAMES_DATA);
 117
 118 void ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
 119                               void (*fn)(const char *name, void *data),
 120                               void *data)
 121 {
 122     DOALL_NAMES_DATA cbdata;
 123
 124     cbdata.number = number;
 125     cbdata.fn = fn;
 126     cbdata.data = data;
 127     CRYPTO_THREAD_read_lock(namemap->lock);
 128     lh_NAMENUM_ENTRY_doall_DOALL_NAMES_DATA(namemap->namenum, do_name,
 129                                             &cbdata);
 130     CRYPTO_THREAD_unlock(namemap->lock);
 131 }
 132
 133 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
 134                             const char *name, size_t name_len)
 135 {
 136     NAMENUM_ENTRY *namenum_entry, namenum_tmpl;
 137     int number = 0;
 138
 139 #ifndef FIPS_MODE
 140     if (namemap == NULL)
 141         namemap = ossl_namemap_stored(NULL);
 142 #endif
 143
 144     if (namemap == NULL)
 145         return 0;
 146
 147     if ((namenum_tmpl.name = OPENSSL_strndup(name, name_len)) == NULL)
 148         return 0;
 149     namenum_tmpl.number = 0;
 150     CRYPTO_THREAD_read_lock(namemap->lock);
 151     namenum_entry =
 152         lh_NAMENUM_ENTRY_retrieve(namemap->namenum, &namenum_tmpl);
 153     if (namenum_entry != NULL)
 154         number = namenum_entry->number;
 155     CRYPTO_THREAD_unlock(namemap->lock);
 156     OPENSSL_free(namenum_tmpl.name);
 157
 158     return number;
 159 }
 160
 161 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name)
 162 {
 163     if (name == NULL)
 164         return 0;
 165
 166     return ossl_namemap_name2num_n(namemap, name, strlen(name));
 167 }
 168
 169 struct num2name_data_st {
 170     size_t idx;                  /* Countdown */
 171     const char *name;            /* Result */
 172 };
 173
 174 static void do_num2name(const char *name, void *vdata)
 175 {
 176     struct num2name_data_st *data = vdata;
 177
 178     if (data->idx > 0)
 179         data->idx--;
 180     else if (data->name == NULL)
 181         data->name = name;
 182 }
 183
 184 const char *ossl_namemap_num2name(const OSSL_NAMEMAP *namemap, int number,
 185                                   size_t idx)
 186 {
 187     struct num2name_data_st data;
 188
 189     data.idx = idx;
 190     data.name = NULL;
 191     ossl_namemap_doall_names(namemap, number, do_num2name, &data);
 192     return data.name;
 193 }
 194
 195 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
 196                             const char *name, size_t name_len)
 197 {
 198     NAMENUM_ENTRY *namenum = NULL;
 199     int tmp_number;
 200
 201 #ifndef FIPS_MODE
 202     if (namemap == NULL)
 203         namemap = ossl_namemap_stored(NULL);
 204 #endif
 205
 206     if (name == NULL || name_len == 0 || namemap == NULL)
 207         return 0;
 208
 209     if ((tmp_number = ossl_namemap_name2num_n(namemap, name, name_len)) != 0)
 210         return tmp_number;       /* Pretend success */
 211
 212     CRYPTO_THREAD_write_lock(namemap->lock);
 213
 214     if ((namenum = OPENSSL_zalloc(sizeof(*namenum))) == NULL
 215         || (namenum->name = OPENSSL_strndup(name, name_len)) == NULL)
 216         goto err;
 217
 218     namenum->number = tmp_number =
 219         number != 0 ? number : ++namemap->max_number;
 220     (void)lh_NAMENUM_ENTRY_insert(namemap->namenum, namenum);
 221
 222     if (lh_NAMENUM_ENTRY_error(namemap->namenum))
 223         goto err;
 224
 225     CRYPTO_THREAD_unlock(namemap->lock);
 226
 227     return tmp_number;
 228
 229  err:
 230     namenum_free(namenum);
 231
 232     CRYPTO_THREAD_unlock(namemap->lock);
 233     return 0;
 234 }
 235
 236 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name)
 237 {
 238     if (name == NULL)
 239         return 0;
 240
 241     return ossl_namemap_add_name_n(namemap, number, name, strlen(name));
 242 }
 243
 244 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
 245                            const char *names, const char separator)
 246 {
 247     const char *p, *q;
 248     size_t l;
 249
 250     /* Check that we have a namemap */
 251     if (!ossl_assert(namemap != NULL)) {
 252         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
 253         return 0;
 254     }
 255
 256     /*
 257      * Check that no name is an empty string, and that all names have at
 258      * most one numeric identity together.
 259      */
 260     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 261         int this_number;
 262
 263         if ((q = strchr(p, separator)) == NULL)
 264             l = strlen(p);       /* offset to \0 */
 265         else
 266             l = q - p;           /* offset to the next separator */
 267
 268         this_number = ossl_namemap_name2num_n(namemap, p, l);
 269
 270         if (*p == '\0' || *p == separator) {
 271             ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_BAD_ALGORITHM_NAME);
 272             return 0;
 273         }
 274         if (number == 0) {
 275             number = this_number;
 276         } else if (this_number != 0 && this_number != number) {
 277             ERR_raise_data(ERR_LIB_CRYPTO, CRYPTO_R_CONFLICTING_NAMES,
 278                            "\"%.*s\" has an existing different identity %d (from \"%s\")",
 279                            l, p, this_number, names);
 280             return 0;
 281         }
 282     }
 283
 284     /* Now that we have checked, register all names */
 285     for (p = names; *p != '\0'; p = (q == NULL ? p + l : q + 1)) {
 286         int this_number;
 287
 288         if ((q = strchr(p, separator)) == NULL)
 289             l = strlen(p);       /* offset to \0 */
 290         else
 291             l = q - p;           /* offset to the next separator */
 292
 293         this_number = ossl_namemap_add_name_n(namemap, number, p, l);
 294         if (number == 0) {
 295             number = this_number;
 296         } else if (this_number != number) {
 297             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_INTERNAL_ERROR,
 298                            "Got number %d when expecting %d",
 299                            this_number, number);
 300             return 0;
 301         }
 302     }
 303
 304     return number;
 305 }
 306
 307 /*-
 308  * Pre-population
 309  * ==============
 310  */
 311
 312 #ifndef FIPS_MODE
 313 #include <openssl/evp.h>
 314
 315 /* Creates an initial namemap with names found in the legacy method db */
 316 static void get_legacy_evp_names(const char *main_name, const char *alias,
 317                                  void *arg)
 318 {
 319     int main_id = ossl_namemap_add_name(arg, 0, main_name);
 320
 321     /*
 322      * We could check that the returned value is the same as main_id,
 323      * but since this is a void function, there's no sane way to report
 324      * the error.  The best we can do is trust ourselve to keep the legacy
 325      * method database conflict free.
 326      *
 327      * This registers any alias with the same number as the main name.
 328      * Should it be that the current |on| *has* the main name, this is
 329      * simply a no-op.
 330      */
 331     if (alias != NULL) {
 332         (void)ossl_namemap_add_name(arg, main_id, alias);
 333     }
 334 }
 335
 336 static void get_legacy_cipher_names(const OBJ_NAME *on, void *arg)
 337 {
 338     const EVP_CIPHER *cipher = (void *)OBJ_NAME_get(on->name, on->type);
 339
 340     get_legacy_evp_names(EVP_CIPHER_name(cipher), on->name, arg);
 341 }
 342
 343 static void get_legacy_md_names(const OBJ_NAME *on, void *arg)
 344 {
 345     const EVP_MD *md = (void *)OBJ_NAME_get(on->name, on->type);
 346     /* We don't want the pkey_type names, so we need some extra care */
 347     int snid, lnid;
 348
 349     snid = OBJ_sn2nid(on->name);
 350     lnid = OBJ_ln2nid(on->name);
 351     if (snid != EVP_MD_pkey_type(md) && lnid != EVP_MD_pkey_type(md))
 352         get_legacy_evp_names(EVP_MD_name(md), on->name, arg);
 353     else
 354         get_legacy_evp_names(EVP_MD_name(md), NULL, arg);
 355 }
 356 #endif
 357
 358 /*-
 359  * Constructors / destructors
 360  * ==========================
 361  */
 362
 363 OSSL_NAMEMAP *ossl_namemap_stored(OPENSSL_CTX *libctx)
 364 {
 365     OSSL_NAMEMAP *namemap =
 366         openssl_ctx_get_data(libctx, OPENSSL_CTX_NAMEMAP_INDEX,
 367                              &stored_namemap_method);
 368
 369 #ifndef FIPS_MODE
 370     if (namemap != NULL && ossl_namemap_empty(namemap)) {
 371         /* Before pilfering, we make sure the legacy database is populated */
 372         OPENSSL_init_crypto(OPENSSL_INIT_ADD_ALL_CIPHERS
 373                             | OPENSSL_INIT_ADD_ALL_DIGESTS, NULL);
 374
 375         OBJ_NAME_do_all(OBJ_NAME_TYPE_CIPHER_METH,
 376                         get_legacy_cipher_names, namemap);
 377         OBJ_NAME_do_all(OBJ_NAME_TYPE_MD_METH,
 378                         get_legacy_md_names, namemap);
 379     }
 380 #endif
 381
 382     return namemap;
 383 }
 384
 385 OSSL_NAMEMAP *ossl_namemap_new(void)
 386 {
 387     OSSL_NAMEMAP *namemap;
 388
 389     if ((namemap = OPENSSL_zalloc(sizeof(*namemap))) != NULL
 390         && (namemap->lock = CRYPTO_THREAD_lock_new()) != NULL
 391         && (namemap->namenum =
 392             lh_NAMENUM_ENTRY_new(namenum_hash, namenum_cmp)) != NULL)
 393         return namemap;
 394
 395     ossl_namemap_free(namemap);
 396     return NULL;
 397 }
 398
 399 void ossl_namemap_free(OSSL_NAMEMAP *namemap)
 400 {
 401     if (namemap == NULL || namemap->stored)
 402         return;
 403
 404     lh_NAMENUM_ENTRY_doall(namemap->namenum, namenum_free);
 405     lh_NAMENUM_ENTRY_free(namemap->namenum);
 406
 407     CRYPTO_THREAD_lock_free(namemap->lock);
 408     OPENSSL_free(namemap);
 409 }