crypto/dh/dh_lib.c

   1 /*
   2  * Copyright 1995-2020 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 /*
  11  * DH low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <stdio.h>
  17 #include <openssl/bn.h>
  18 #include <openssl/engine.h>
  19 #include <openssl/obj_mac.h>
  20 #include <openssl/core_names.h>
  21 #include "internal/cryptlib.h"
  22 #include "internal/refcount.h"
  23 #include "crypto/evp.h"
  24 #include "crypto/dh.h"
  25 #include "dh_local.h"
  26
  27 static DH *dh_new_intern(ENGINE *engine, OPENSSL_CTX *libctx);
  28
  29 #ifndef FIPS_MODE
  30 int DH_set_method(DH *dh, const DH_METHOD *meth)
  31 {
  32     /*
  33      * NB: The caller is specifically setting a method, so it's not up to us
  34      * to deal with which ENGINE it comes from.
  35      */
  36     const DH_METHOD *mtmp;
  37     mtmp = dh->meth;
  38     if (mtmp->finish)
  39         mtmp->finish(dh);
  40 #ifndef OPENSSL_NO_ENGINE
  41     ENGINE_finish(dh->engine);
  42     dh->engine = NULL;
  43 #endif
  44     dh->meth = meth;
  45     if (meth->init)
  46         meth->init(dh);
  47     return 1;
  48 }
  49
  50 const DH_METHOD *dh_get_method(const DH *dh)
  51 {
  52     return dh->meth;
  53 }
  54
  55 DH *DH_new(void)
  56 {
  57     return dh_new_intern(NULL, NULL);
  58 }
  59
  60 DH *DH_new_method(ENGINE *engine)
  61 {
  62     return dh_new_intern(engine, NULL);
  63 }
  64 #endif /* !FIPS_MODE */
  65
  66 DH *dh_new_with_libctx(OPENSSL_CTX *libctx)
  67 {
  68     return dh_new_intern(NULL, libctx);
  69 }
  70
  71 static DH *dh_new_intern(ENGINE *engine, OPENSSL_CTX *libctx)
  72 {
  73     DH *ret = OPENSSL_zalloc(sizeof(*ret));
  74
  75     if (ret == NULL) {
  76         DHerr(0, ERR_R_MALLOC_FAILURE);
  77         return NULL;
  78     }
  79
  80     ret->references = 1;
  81     ret->lock = CRYPTO_THREAD_lock_new();
  82     if (ret->lock == NULL) {
  83         DHerr(0, ERR_R_MALLOC_FAILURE);
  84         OPENSSL_free(ret);
  85         return NULL;
  86     }
  87
  88     ret->libctx = libctx;
  89     ret->meth = DH_get_default_method();
  90 #if !defined(FIPS_MODE) && !defined(OPENSSL_NO_ENGINE)
  91     ret->flags = ret->meth->flags;  /* early default init */
  92     if (engine) {
  93         if (!ENGINE_init(engine)) {
  94             DHerr(0, ERR_R_ENGINE_LIB);
  95             goto err;
  96         }
  97         ret->engine = engine;
  98     } else
  99         ret->engine = ENGINE_get_default_DH();
 100     if (ret->engine) {
 101         ret->meth = ENGINE_get_DH(ret->engine);
 102         if (ret->meth == NULL) {
 103             DHerr(0, ERR_R_ENGINE_LIB);
 104             goto err;
 105         }
 106     }
 107 #endif
 108
 109     ret->flags = ret->meth->flags;
 110
 111 #ifndef FIPS_MODE
 112     if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data))
 113         goto err;
 114 #endif /* FIPS_MODE */
 115
 116     if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
 117         DHerr(0, ERR_R_INIT_FAIL);
 118         goto err;
 119     }
 120
 121     return ret;
 122
 123  err:
 124     DH_free(ret);
 125     return NULL;
 126 }
 127
 128 void DH_free(DH *r)
 129 {
 130     int i;
 131
 132     if (r == NULL)
 133         return;
 134
 135     CRYPTO_DOWN_REF(&r->references, &i, r->lock);
 136     REF_PRINT_COUNT("DH", r);
 137     if (i > 0)
 138         return;
 139     REF_ASSERT_ISNT(i < 0);
 140
 141     if (r->meth != NULL && r->meth->finish != NULL)
 142         r->meth->finish(r);
 143 #if !defined(FIPS_MODE)
 144 # if !defined(OPENSSL_NO_ENGINE)
 145     ENGINE_finish(r->engine);
 146 # endif
 147     CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);
 148 #endif
 149
 150     CRYPTO_THREAD_lock_free(r->lock);
 151
 152     ffc_params_cleanup(&r->params);
 153     BN_clear_free(r->pub_key);
 154     BN_clear_free(r->priv_key);
 155     OPENSSL_free(r);
 156 }
 157
 158 int DH_up_ref(DH *r)
 159 {
 160     int i;
 161
 162     if (CRYPTO_UP_REF(&r->references, &i, r->lock) <= 0)
 163         return 0;
 164
 165     REF_PRINT_COUNT("DH", r);
 166     REF_ASSERT_ISNT(i < 2);
 167     return ((i > 1) ? 1 : 0);
 168 }
 169
 170 #ifndef FIPS_MODE
 171 int DH_set_ex_data(DH *d, int idx, void *arg)
 172 {
 173     return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
 174 }
 175
 176 void *DH_get_ex_data(const DH *d, int idx)
 177 {
 178     return CRYPTO_get_ex_data(&d->ex_data, idx);
 179 }
 180 #endif
 181
 182 int DH_bits(const DH *dh)
 183 {
 184     return BN_num_bits(dh->params.p);
 185 }
 186
 187 int DH_size(const DH *dh)
 188 {
 189     return BN_num_bytes(dh->params.p);
 190 }
 191
 192 int DH_security_bits(const DH *dh)
 193 {
 194     int N;
 195     if (dh->params.q != NULL)
 196         N = BN_num_bits(dh->params.q);
 197     else if (dh->length)
 198         N = dh->length;
 199     else
 200         N = -1;
 201     return BN_security_bits(BN_num_bits(dh->params.p), N);
 202 }
 203
 204 void DH_get0_pqg(const DH *dh,
 205                  const BIGNUM **p, const BIGNUM **q, const BIGNUM **g)
 206 {
 207     ffc_params_get0_pqg(&dh->params, p, q, g);
 208 }
 209
 210 int DH_set0_pqg(DH *dh, BIGNUM *p, BIGNUM *q, BIGNUM *g)
 211 {
 212     /* If the fields p and g in d are NULL, the corresponding input
 213      * parameters MUST be non-NULL.  q may remain NULL.
 214      */
 215     if ((dh->params.p == NULL && p == NULL)
 216         || (dh->params.g == NULL && g == NULL))
 217         return 0;
 218
 219     ffc_params_set0_pqg(&dh->params, p, q, g);
 220     dh->params.nid = NID_undef;
 221     /*
 222      * Check if this is a named group. If it finds a named group then the
 223      * 'q' and 'length' value are either already set or are set by the
 224      * call.
 225      */
 226     if (DH_get_nid(dh) == NID_undef) {
 227         /* If its not a named group then set the 'length' if q is not NULL */
 228         if (q != NULL)
 229             dh->length = BN_num_bits(q);
 230     }
 231     dh->dirty_cnt++;
 232     return 1;
 233 }
 234
 235 long DH_get_length(const DH *dh)
 236 {
 237     return dh->length;
 238 }
 239
 240 int DH_set_length(DH *dh, long length)
 241 {
 242     dh->length = length;
 243     return 1;
 244 }
 245
 246 void DH_get0_key(const DH *dh, const BIGNUM **pub_key, const BIGNUM **priv_key)
 247 {
 248     if (pub_key != NULL)
 249         *pub_key = dh->pub_key;
 250     if (priv_key != NULL)
 251         *priv_key = dh->priv_key;
 252 }
 253
 254 int DH_set0_key(DH *dh, BIGNUM *pub_key, BIGNUM *priv_key)
 255 {
 256     if (pub_key != NULL) {
 257         BN_clear_free(dh->pub_key);
 258         dh->pub_key = pub_key;
 259     }
 260     if (priv_key != NULL) {
 261         BN_clear_free(dh->priv_key);
 262         dh->priv_key = priv_key;
 263     }
 264
 265     dh->dirty_cnt++;
 266     return 1;
 267 }
 268
 269 const BIGNUM *DH_get0_p(const DH *dh)
 270 {
 271     return dh->params.p;
 272 }
 273
 274 const BIGNUM *DH_get0_q(const DH *dh)
 275 {
 276     return dh->params.q;
 277 }
 278
 279 const BIGNUM *DH_get0_g(const DH *dh)
 280 {
 281     return dh->params.g;
 282 }
 283
 284 const BIGNUM *DH_get0_priv_key(const DH *dh)
 285 {
 286     return dh->priv_key;
 287 }
 288
 289 const BIGNUM *DH_get0_pub_key(const DH *dh)
 290 {
 291     return dh->pub_key;
 292 }
 293
 294 void DH_clear_flags(DH *dh, int flags)
 295 {
 296     dh->flags &= ~flags;
 297 }
 298
 299 int DH_test_flags(const DH *dh, int flags)
 300 {
 301     return dh->flags & flags;
 302 }
 303
 304 void DH_set_flags(DH *dh, int flags)
 305 {
 306     dh->flags |= flags;
 307 }
 308
 309 #ifndef FIPS_MODE
 310 ENGINE *DH_get0_engine(DH *dh)
 311 {
 312     return dh->engine;
 313 }
 314 #endif /*FIPS_MODE */
 315
 316 FFC_PARAMS *dh_get0_params(DH *dh)
 317 {
 318     return &dh->params;
 319 }
 320 int dh_get0_nid(const DH *dh)
 321 {
 322     return dh->params.nid;
 323 }
 324
 325 int dh_ffc_params_fromdata(DH *dh, const OSSL_PARAM params[])
 326 {
 327     int ret;
 328     FFC_PARAMS *ffc;
 329
 330     if (dh == NULL)
 331         return 0;
 332     ffc = dh_get0_params(dh);
 333     if (ffc == NULL)
 334         return 0;
 335
 336     ret = ffc_params_fromdata(ffc, params);
 337     if (ret) {
 338         DH_get_nid(dh);
 339         dh->dirty_cnt++;
 340     }
 341     return ret;
 342 }
 343
 344 static int dh_paramgen_check(EVP_PKEY_CTX *ctx)
 345 {
 346     if (ctx == NULL || !EVP_PKEY_CTX_IS_GEN_OP(ctx)) {
 347         ERR_raise(ERR_LIB_EVP, EVP_R_COMMAND_NOT_SUPPORTED);
 348         /* Uses the same return values as EVP_PKEY_CTX_ctrl */
 349         return -2;
 350     }
 351     /* If key type not DH return error */
 352     if (ctx->pmeth != NULL
 353         && ctx->pmeth->pkey_id != EVP_PKEY_DH
 354         && ctx->pmeth->pkey_id != EVP_PKEY_DHX)
 355         return -1;
 356     return 1;
 357 }
 358
 359 int EVP_PKEY_CTX_set_dh_paramgen_gindex(EVP_PKEY_CTX *ctx, int gindex)
 360 {
 361     int ret;
 362     OSSL_PARAM params[2], *p = params;
 363
 364     if ((ret = dh_paramgen_check(ctx)) <= 0)
 365         return ret;
 366
 367     *p++ = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_FFC_GINDEX, &gindex);
 368     *p++ = OSSL_PARAM_construct_end();
 369
 370     return EVP_PKEY_CTX_set_params(ctx, params);
 371 }
 372
 373 int EVP_PKEY_CTX_set_dh_paramgen_seed(EVP_PKEY_CTX *ctx,
 374                                       const unsigned char *seed,
 375                                       size_t seedlen)
 376 {
 377     int ret;
 378     OSSL_PARAM params[2], *p = params;
 379
 380     if ((ret = dh_paramgen_check(ctx)) <= 0)
 381         return ret;
 382
 383     *p++ = OSSL_PARAM_construct_octet_string(OSSL_PKEY_PARAM_FFC_SEED,
 384                                              (void *)seed, seedlen);
 385     *p++ = OSSL_PARAM_construct_end();
 386
 387     return EVP_PKEY_CTX_set_params(ctx, params);
 388 }
 389
 390 int EVP_PKEY_CTX_set_dh_paramgen_type(EVP_PKEY_CTX *ctx, int typ)
 391 {
 392     int ret;
 393     OSSL_PARAM params[2], *p = params;
 394     const char *name;
 395
 396     if ((ret = dh_paramgen_check(ctx)) <= 0)
 397         return ret;
 398
 399 #if !defined(FIPS_MODE)
 400     /* TODO(3.0): Remove this eventually when no more legacy */
 401     if (ctx->op.keymgmt.genctx == NULL)
 402         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH, EVP_PKEY_OP_PARAMGEN,
 403                                  EVP_PKEY_CTRL_DH_PARAMGEN_TYPE, typ, NULL);
 404 #endif
 405
 406     name = dh_gen_type_id2name(typ);
 407     if (name == NULL)
 408         return 0;
 409     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_TYPE,
 410                                             (char *) name, 0);
 411     *p++ = OSSL_PARAM_construct_end();
 412
 413     return EVP_PKEY_CTX_set_params(ctx, params);
 414 }
 415
 416 int EVP_PKEY_CTX_set_dh_paramgen_prime_len(EVP_PKEY_CTX *ctx, int pbits)
 417 {
 418     int ret;
 419     OSSL_PARAM params[2], *p = params;
 420     size_t bits = pbits;
 421
 422     if ((ret = dh_paramgen_check(ctx)) <= 0)
 423         return ret;
 424
 425 #if !defined(FIPS_MODE)
 426     /* TODO(3.0): Remove this eventually when no more legacy */
 427     if (ctx->op.keymgmt.genctx == NULL)
 428         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH, EVP_PKEY_OP_PARAMGEN,
 429                                  EVP_PKEY_CTRL_DH_PARAMGEN_PRIME_LEN, pbits,
 430                                  NULL);
 431 #endif
 432     *p++ = OSSL_PARAM_construct_size_t(OSSL_PKEY_PARAM_FFC_PBITS, &bits);
 433     *p++ = OSSL_PARAM_construct_end();
 434     return EVP_PKEY_CTX_set_params(ctx, params);
 435 }
 436
 437 int EVP_PKEY_CTX_set_dh_paramgen_subprime_len(EVP_PKEY_CTX *ctx, int qbits)
 438 {
 439     int ret;
 440     OSSL_PARAM params[2], *p = params;
 441     size_t bits2 = qbits;
 442
 443     if ((ret = dh_paramgen_check(ctx)) <= 0)
 444         return ret;
 445
 446 #if !defined(FIPS_MODE)
 447     /* TODO(3.0): Remove this eventually when no more legacy */
 448     if (ctx->op.keymgmt.genctx == NULL)
 449         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH, EVP_PKEY_OP_PARAMGEN,
 450                                  EVP_PKEY_CTRL_DH_PARAMGEN_SUBPRIME_LEN, qbits,
 451                                  NULL);
 452 #endif
 453     *p++ = OSSL_PARAM_construct_size_t(OSSL_PKEY_PARAM_FFC_QBITS, &bits2);
 454     *p++ = OSSL_PARAM_construct_end();
 455
 456     return EVP_PKEY_CTX_set_params(ctx, params);
 457 }
 458
 459 int EVP_PKEY_CTX_set_dh_paramgen_generator(EVP_PKEY_CTX *ctx, int gen)
 460 {
 461     int ret;
 462     OSSL_PARAM params[2], *p = params;
 463
 464     if ((ret = dh_paramgen_check(ctx)) <= 0)
 465         return ret;
 466
 467 #if !defined(FIPS_MODE)
 468     /* TODO(3.0): Remove this eventually when no more legacy */
 469     if (ctx->op.keymgmt.genctx == NULL)
 470         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH, EVP_PKEY_OP_PARAMGEN,
 471                                  EVP_PKEY_CTRL_DH_PARAMGEN_GENERATOR, gen, NULL);
 472 #endif
 473
 474     *p++ = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_FFC_GENERATOR, &gen);
 475     *p++ = OSSL_PARAM_construct_end();
 476
 477     return EVP_PKEY_CTX_set_params(ctx, params);
 478 }
 479
 480 int EVP_PKEY_CTX_set_dh_rfc5114(EVP_PKEY_CTX *ctx, int gen)
 481 {
 482     int ret;
 483     OSSL_PARAM params[2], *p = params;
 484     const char *name;
 485
 486     if ((ret = dh_paramgen_check(ctx)) <= 0)
 487         return ret;
 488
 489 #if !defined(FIPS_MODE)
 490     /* TODO(3.0): Remove this eventually when no more legacy */
 491     if (ctx->op.keymgmt.genctx == NULL)
 492         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DHX, EVP_PKEY_OP_PARAMGEN,
 493                                  EVP_PKEY_CTRL_DH_RFC5114, gen, NULL);
 494 #endif
 495     name = ffc_named_group_from_uid(gen);
 496     if (name == NULL)
 497         return 0;
 498
 499     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_GROUP,
 500                                             (void *)name, 0);
 501     *p++ = OSSL_PARAM_construct_end();
 502     return EVP_PKEY_CTX_set_params(ctx, params);
 503 }
 504
 505 int EVP_PKEY_CTX_set_dhx_rfc5114(EVP_PKEY_CTX *ctx, int gen)
 506 {
 507     return EVP_PKEY_CTX_set_dh_rfc5114(ctx, gen);
 508 }
 509
 510 int EVP_PKEY_CTX_set_dh_nid(EVP_PKEY_CTX *ctx, int nid)
 511 {
 512     int ret;
 513     OSSL_PARAM params[2], *p = params;
 514     const char *name;
 515
 516     if ((ret = dh_paramgen_check(ctx)) <= 0)
 517         return ret;
 518
 519 #if !defined(FIPS_MODE)
 520     /* TODO(3.0): Remove this eventually when no more legacy */
 521     if (ctx->op.keymgmt.genctx == NULL)
 522         return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH,
 523                                  EVP_PKEY_OP_PARAMGEN | EVP_PKEY_OP_KEYGEN,
 524                                  EVP_PKEY_CTRL_DH_NID, nid, NULL);
 525 #endif
 526     name = ffc_named_group_from_uid(nid);
 527     if (name == NULL)
 528         return 0;
 529
 530     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_GROUP,
 531                                             (void *)name, 0);
 532     *p++ = OSSL_PARAM_construct_end();
 533     return EVP_PKEY_CTX_set_params(ctx, params);
 534 }