crypto/evp/evp_fetch.c

   1 /*
   2  * Copyright 2019-2020 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 <stddef.h>
  11 #include <openssl/types.h>
  12 #include <openssl/evp.h>
  13 #include <openssl/core.h>
  14 #include "internal/cryptlib.h"
  15 #include "internal/thread_once.h"
  16 #include "internal/property.h"
  17 #include "internal/core.h"
  18 #include "internal/provider.h"
  19 #include "internal/namemap.h"
  20 #include "crypto/evp.h"    /* evp_local.h needs it */
  21 #include "evp_local.h"
  22
  23 #define NAME_SEPARATOR ':'
  24
  25 static void evp_method_store_free(void *vstore)
  26 {
  27     ossl_method_store_free(vstore);
  28 }
  29
  30 static void *evp_method_store_new(OPENSSL_CTX *ctx)
  31 {
  32     return ossl_method_store_new(ctx);
  33 }
  34
  35
  36 static const OPENSSL_CTX_METHOD evp_method_store_method = {
  37     evp_method_store_new,
  38     evp_method_store_free,
  39 };
  40
  41 /* Data to be passed through ossl_method_construct() */
  42 struct evp_method_data_st {
  43     OPENSSL_CTX *libctx;
  44     OSSL_METHOD_CONSTRUCT_METHOD *mcm;
  45     int operation_id;            /* For get_evp_method_from_store() */
  46     int name_id;                 /* For get_evp_method_from_store() */
  47     const char *names;           /* For get_evp_method_from_store() */
  48     const char *propquery;       /* For get_evp_method_from_store() */
  49     void *(*method_from_dispatch)(int name_id, const OSSL_DISPATCH *,
  50                                   OSSL_PROVIDER *);
  51     int (*refcnt_up_method)(void *method);
  52     void (*destruct_method)(void *method);
  53 };
  54
  55 /*
  56  * Generic routines to fetch / create EVP methods with ossl_method_construct()
  57  */
  58 static void *alloc_tmp_evp_method_store(OPENSSL_CTX *ctx)
  59 {
  60     return ossl_method_store_new(ctx);
  61 }
  62
  63  static void dealloc_tmp_evp_method_store(void *store)
  64 {
  65     if (store != NULL)
  66         ossl_method_store_free(store);
  67 }
  68
  69 static OSSL_METHOD_STORE *get_evp_method_store(OPENSSL_CTX *libctx)
  70 {
  71     return openssl_ctx_get_data(libctx, OPENSSL_CTX_EVP_METHOD_STORE_INDEX,
  72                                 &evp_method_store_method);
  73 }
  74
  75 /*
  76  * To identify the method in the EVP method store, we mix the name identity
  77  * with the operation identity, under the assumption that we don't have more
  78  * than 2^24 names or more than 2^8 operation types.
  79  *
  80  * The resulting identity is a 32-bit integer, composed like this:
  81  *
  82  * +---------24 bits--------+-8 bits-+
  83  * |      name identity     | op id  |
  84  * +------------------------+--------+
  85  */
  86 static uint32_t evp_method_id(int name_id, unsigned int operation_id)
  87 {
  88     if (!ossl_assert(name_id > 0 && name_id < (1 << 24))
  89         || !ossl_assert(operation_id > 0 && operation_id < (1 << 8)))
  90         return 0;
  91     return ((name_id << 8) & 0xFFFFFF00) | (operation_id & 0x000000FF);
  92 }
  93
  94 static void *get_evp_method_from_store(OPENSSL_CTX *libctx, void *store,
  95                                        void *data)
  96 {
  97     struct evp_method_data_st *methdata = data;
  98     void *method = NULL;
  99     int name_id;
 100     uint32_t meth_id;
 101
 102     /*
 103      * get_evp_method_from_store() is only called to try and get the method
 104      * that evp_generic_fetch() is asking for, and the operation id as well
 105      * as the name or name id are passed via methdata.
 106      */
 107     if ((name_id = methdata->name_id) == 0) {
 108         OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 109         const char *names = methdata->names;
 110         const char *q = strchr(names, NAME_SEPARATOR);
 111         size_t l = (q == NULL ? strlen(names) : (size_t)(q - names));
 112
 113         if (namemap == 0)
 114             return NULL;
 115         name_id = ossl_namemap_name2num_n(namemap, names, l);
 116     }
 117
 118     if (name_id == 0
 119         || (meth_id = evp_method_id(name_id, methdata->operation_id)) == 0)
 120         return NULL;
 121
 122     if (store == NULL
 123         && (store = get_evp_method_store(libctx)) == NULL)
 124         return NULL;
 125
 126     if (!ossl_method_store_fetch(store, meth_id, methdata->propquery,
 127                                  &method))
 128         return NULL;
 129     return method;
 130 }
 131
 132 static int put_evp_method_in_store(OPENSSL_CTX *libctx, void *store,
 133                                    void *method, const OSSL_PROVIDER *prov,
 134                                    int operation_id, const char *names,
 135                                    const char *propdef, void *data)
 136 {
 137     struct evp_method_data_st *methdata = data;
 138     OSSL_NAMEMAP *namemap;
 139     int name_id;
 140     uint32_t meth_id;
 141     size_t l = 0;
 142
 143     /*
 144      * put_evp_method_in_store() is only called with an EVP method that was
 145      * successfully created by construct_method() below, which means that
 146      * all the names should already be stored in the namemap with the same
 147      * numeric identity, so just use the first to get that identity.
 148      */
 149     if (names != NULL) {
 150         const char *q = strchr(names, NAME_SEPARATOR);
 151
 152         l = (q == NULL ? strlen(names) : (size_t)(q - names));
 153     }
 154
 155     if ((namemap = ossl_namemap_stored(libctx)) == NULL
 156         || (name_id = ossl_namemap_name2num_n(namemap, names, l)) == 0
 157         || (meth_id = evp_method_id(name_id, operation_id)) == 0)
 158         return 0;
 159
 160     if (store == NULL
 161         && (store = get_evp_method_store(libctx)) == NULL)
 162         return 0;
 163
 164     return ossl_method_store_add(store, prov, meth_id, propdef, method,
 165                                  methdata->refcnt_up_method,
 166                                  methdata->destruct_method);
 167 }
 168
 169 /*
 170  * The core fetching functionality passes the name of the implementation.
 171  * This function is responsible to getting an identity number for it.
 172  */
 173 static void *construct_evp_method(const OSSL_ALGORITHM *algodef,
 174                                   OSSL_PROVIDER *prov, void *data)
 175 {
 176     /*
 177      * This function is only called if get_evp_method_from_store() returned
 178      * NULL, so it's safe to say that of all the spots to create a new
 179      * namemap entry, this is it.  Should the name already exist there, we
 180      * know that ossl_namemap_add_name() will return its corresponding
 181      * number.
 182      */
 183     struct evp_method_data_st *methdata = data;
 184     OPENSSL_CTX *libctx = ossl_provider_library_context(prov);
 185     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 186     const char *names = algodef->algorithm_names;
 187     int name_id = ossl_namemap_add_names(namemap, 0, names, NAME_SEPARATOR);
 188
 189     if (name_id == 0)
 190         return NULL;
 191     return methdata->method_from_dispatch(name_id, algodef->implementation,
 192                                           prov);
 193 }
 194
 195 static void destruct_evp_method(void *method, void *data)
 196 {
 197     struct evp_method_data_st *methdata = data;
 198
 199     methdata->destruct_method(method);
 200 }
 201
 202 static void *
 203 inner_evp_generic_fetch(OPENSSL_CTX *libctx, int operation_id,
 204                         int name_id, const char *name,
 205                         const char *properties,
 206                         void *(*new_method)(int name_id,
 207                                             const OSSL_DISPATCH *fns,
 208                                             OSSL_PROVIDER *prov),
 209                         int (*up_ref_method)(void *),
 210                         void (*free_method)(void *))
 211 {
 212     OSSL_METHOD_STORE *store = get_evp_method_store(libctx);
 213     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 214     uint32_t meth_id = 0;
 215     void *method = NULL;
 216
 217     if (store == NULL || namemap == NULL)
 218         return NULL;
 219
 220     /*
 221      * If there's ever an operation_id == 0 passed, we have an internal
 222      * programming error.
 223      */
 224     if (!ossl_assert(operation_id > 0))
 225         return NULL;
 226
 227     /*
 228      * If we have been passed neither a name_id or a name, we have an
 229      * internal programming error.
 230      */
 231     if (!ossl_assert(name_id != 0 || name != NULL))
 232         return NULL;
 233
 234     /* If we haven't received a name id yet, try to get one for the name */
 235     if (name_id == 0)
 236         name_id = ossl_namemap_name2num(namemap, name);
 237
 238     /*
 239      * If we have a name id, calculate a method id with evp_method_id().
 240      *
 241      * evp_method_id returns 0 if we have too many operations (more than
 242      * about 2^8) or too many names (more than about 2^24).  In that case,
 243      * we can't create any new method.
 244      */
 245     if (name_id != 0 && (meth_id = evp_method_id(name_id, operation_id)) == 0)
 246         return NULL;
 247
 248     if (meth_id == 0
 249         || !ossl_method_store_cache_get(store, meth_id, properties, &method)) {
 250         OSSL_METHOD_CONSTRUCT_METHOD mcm = {
 251             alloc_tmp_evp_method_store,
 252             dealloc_tmp_evp_method_store,
 253             get_evp_method_from_store,
 254             put_evp_method_in_store,
 255             construct_evp_method,
 256             destruct_evp_method
 257         };
 258         struct evp_method_data_st mcmdata;
 259
 260         mcmdata.mcm = &mcm;
 261         mcmdata.libctx = libctx;
 262         mcmdata.operation_id = operation_id;
 263         mcmdata.name_id = name_id;
 264         mcmdata.names = name;
 265         mcmdata.propquery = properties;
 266         mcmdata.method_from_dispatch = new_method;
 267         mcmdata.refcnt_up_method = up_ref_method;
 268         mcmdata.destruct_method = free_method;
 269         if ((method = ossl_method_construct(libctx, operation_id,
 270                                             0 /* !force_cache */,
 271                                             &mcm, &mcmdata)) != NULL) {
 272             /*
 273              * If construction did create a method for us, we know that
 274              * there is a correct name_id and meth_id, since those have
 275              * already been calculated in get_evp_method_from_store() and
 276              * put_evp_method_in_store() above.
 277              */
 278             if (name_id == 0)
 279                 name_id = ossl_namemap_name2num(namemap, name);
 280             meth_id = evp_method_id(name_id, operation_id);
 281             ossl_method_store_cache_set(store, meth_id, properties, method,
 282                                         up_ref_method, free_method);
 283         }
 284     }
 285
 286     return method;
 287 }
 288
 289 void *evp_generic_fetch(OPENSSL_CTX *libctx, int operation_id,
 290                         const char *name, const char *properties,
 291                         void *(*new_method)(int name_id,
 292                                             const OSSL_DISPATCH *fns,
 293                                             OSSL_PROVIDER *prov),
 294                         int (*up_ref_method)(void *),
 295                         void (*free_method)(void *))
 296 {
 297     void *ret = inner_evp_generic_fetch(libctx,
 298                                         operation_id, 0, name, properties,
 299                                         new_method, up_ref_method, free_method);
 300
 301     if (ret == NULL) {
 302         int code = EVP_R_FETCH_FAILED;
 303
 304 #ifdef FIPS_MODULE
 305         ERR_raise(ERR_LIB_EVP, code);
 306 #else
 307         ERR_raise_data(ERR_LIB_EVP, code,
 308                        "%s, Algorithm (%s), Properties (%s)",
 309                        (openssl_ctx_is_default(libctx)
 310                         ? "Default library context"
 311                         : "Non-default library context"),
 312                        name = NULL ? "<null>" : name,
 313                        properties == NULL ? "<null>" : properties);
 314 #endif
 315     }
 316     return ret;
 317 }
 318
 319 /*
 320  * evp_generic_fetch_by_number() is special, and only returns methods for
 321  * already known names, i.e. it refuses to work if no name_id can be found
 322  * (it's considered an internal programming error).
 323  * This is meant to be used when one method needs to fetch an associated
 324  * other method.
 325  */
 326 void *evp_generic_fetch_by_number(OPENSSL_CTX *libctx, int operation_id,
 327                                   int name_id, const char *properties,
 328                                   void *(*new_method)(int name_id,
 329                                                       const OSSL_DISPATCH *fns,
 330                                                       OSSL_PROVIDER *prov),
 331                                   int (*up_ref_method)(void *),
 332                                   void (*free_method)(void *))
 333 {
 334     void *ret = inner_evp_generic_fetch(libctx,
 335                                         operation_id, name_id, NULL,
 336                                         properties, new_method, up_ref_method,
 337                                         free_method);
 338
 339     if (ret == NULL) {
 340         int code = EVP_R_FETCH_FAILED;
 341
 342 #ifdef FIPS_MODULE
 343         ERR_raise(ERR_LIB_EVP, code);
 344 #else
 345         {
 346             OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 347             const char *name = (namemap == NULL)
 348                                ? NULL
 349                                : ossl_namemap_num2name(namemap, name_id, 0);
 350
 351             ERR_raise_data(ERR_LIB_EVP, code,
 352                            "%s, Algorithm (%s), Properties (%s)",
 353                            (openssl_ctx_is_default(libctx)
 354                             ? "Default library context"
 355                             : "Non-default library context"),
 356                            name = NULL ? "<null>" : name,
 357                            properties == NULL ? "<null>" : properties);
 358         }
 359 #endif
 360     }
 361     return ret;
 362 }
 363
 364 int EVP_set_default_properties(OPENSSL_CTX *libctx, const char *propq)
 365 {
 366     OSSL_METHOD_STORE *store = get_evp_method_store(libctx);
 367
 368     if (store != NULL)
 369         return ossl_method_store_set_global_properties(store, propq);
 370     EVPerr(EVP_F_EVP_SET_DEFAULT_PROPERTIES, ERR_R_INTERNAL_ERROR);
 371     return 0;
 372 }
 373
 374 struct do_all_data_st {
 375     void (*user_fn)(void *method, void *arg);
 376     void *user_arg;
 377     void *(*new_method)(const int name_id, const OSSL_DISPATCH *fns,
 378                         OSSL_PROVIDER *prov);
 379     void (*free_method)(void *);
 380 };
 381
 382 static void do_one(OSSL_PROVIDER *provider, const OSSL_ALGORITHM *algo,
 383                    int no_store, void *vdata)
 384 {
 385     struct do_all_data_st *data = vdata;
 386     OPENSSL_CTX *libctx = ossl_provider_library_context(provider);
 387     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 388     int name_id = ossl_namemap_add_names(namemap, 0, algo->algorithm_names,
 389                                          NAME_SEPARATOR);
 390     void *method = NULL;
 391
 392     if (name_id != 0)
 393         method = data->new_method(name_id, algo->implementation, provider);
 394
 395     if (method != NULL) {
 396         data->user_fn(method, data->user_arg);
 397         data->free_method(method);
 398     }
 399 }
 400
 401 void evp_generic_do_all(OPENSSL_CTX *libctx, int operation_id,
 402                         void (*user_fn)(void *method, void *arg),
 403                         void *user_arg,
 404                         void *(*new_method)(int name_id,
 405                                             const OSSL_DISPATCH *fns,
 406                                             OSSL_PROVIDER *prov),
 407                         void (*free_method)(void *))
 408 {
 409     struct do_all_data_st data;
 410
 411     data.new_method = new_method;
 412     data.free_method = free_method;
 413     data.user_fn = user_fn;
 414     data.user_arg = user_arg;
 415     ossl_algorithm_do_all(libctx, operation_id, NULL, do_one, &data);
 416 }
 417
 418 const char *evp_first_name(const OSSL_PROVIDER *prov, int name_id)
 419 {
 420     OPENSSL_CTX *libctx = ossl_provider_library_context(prov);
 421     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 422
 423     return ossl_namemap_num2name(namemap, name_id, 0);
 424 }
 425
 426 int evp_is_a(OSSL_PROVIDER *prov, int number,
 427              const char *legacy_name, const char *name)
 428 {
 429     /*
 430      * For a |prov| that is NULL, the library context will be NULL
 431      */
 432     OPENSSL_CTX *libctx = ossl_provider_library_context(prov);
 433     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 434
 435     if (prov == NULL)
 436         number = ossl_namemap_name2num(namemap, legacy_name);
 437     return ossl_namemap_name2num(namemap, name) == number;
 438 }
 439
 440 void evp_names_do_all(OSSL_PROVIDER *prov, int number,
 441                       void (*fn)(const char *name, void *data),
 442                       void *data)
 443 {
 444     OPENSSL_CTX *libctx = ossl_provider_library_context(prov);
 445     OSSL_NAMEMAP *namemap = ossl_namemap_stored(libctx);
 446
 447     ossl_namemap_doall_names(namemap, number, fn, data);
 448 }