1 /* 2 * Copyright 2006-2022 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 /* 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/x509.h> 18 #include <openssl/asn1.h> 19 #include <openssl/bn.h> 20 #include <openssl/core_names.h> 21 #include <openssl/param_build.h> 22 #include "internal/ffc.h" 23 #include "internal/cryptlib.h" 24 #include "crypto/asn1.h" 25 #include "crypto/dh.h" 26 #include "crypto/evp.h" 27 #include "dh_local.h" 28 29 /* 30 * i2d/d2i like DH parameter functions which use the appropriate routine for 31 * PKCS#3 DH or X9.42 DH. 32 */ 33 34 static DH *d2i_dhp(const EVP_PKEY *pkey, const unsigned char **pp, 35 long length) 36 { 37 DH *dh = NULL; 38 int is_dhx = (pkey->ameth == &ossl_dhx_asn1_meth); 39 40 if (is_dhx) 41 dh = d2i_DHxparams(NULL, pp, length); 42 else 43 dh = d2i_DHparams(NULL, pp, length); 44 45 return dh; 46 } 47 48 static int i2d_dhp(const EVP_PKEY *pkey, const DH *a, unsigned char **pp) 49 { 50 if (pkey->ameth == &ossl_dhx_asn1_meth) 51 return i2d_DHxparams(a, pp); 52 return i2d_DHparams(a, pp); 53 } 54 55 static void int_dh_free(EVP_PKEY *pkey) 56 { 57 DH_free(pkey->pkey.dh); 58 } 59 60 static int dh_pub_decode(EVP_PKEY *pkey, const X509_PUBKEY *pubkey) 61 { 62 const unsigned char *p, *pm; 63 int pklen, pmlen; 64 int ptype; 65 const void *pval; 66 const ASN1_STRING *pstr; 67 X509_ALGOR *palg; 68 ASN1_INTEGER *public_key = NULL; 69 70 DH *dh = NULL; 71 72 if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey)) 73 return 0; 74 X509_ALGOR_get0(NULL, &ptype, &pval, palg); 75 76 if (ptype != V_ASN1_SEQUENCE) { 77 ERR_raise(ERR_LIB_DH, DH_R_PARAMETER_ENCODING_ERROR); 78 goto err; 79 } 80 81 pstr = pval; 82 pm = pstr->data; 83 pmlen = pstr->length; 84 85 if ((dh = d2i_dhp(pkey, &pm, pmlen)) == NULL) { 86 ERR_raise(ERR_LIB_DH, DH_R_DECODE_ERROR); 87 goto err; 88 } 89 90 if ((public_key = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL) { 91 ERR_raise(ERR_LIB_DH, DH_R_DECODE_ERROR); 92 goto err; 93 } 94 95 /* We have parameters now set public key */ 96 if ((dh->pub_key = ASN1_INTEGER_to_BN(public_key, NULL)) == NULL) { 97 ERR_raise(ERR_LIB_DH, DH_R_BN_DECODE_ERROR); 98 goto err; 99 } 100 101 ASN1_INTEGER_free(public_key); 102 EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, dh); 103 return 1; 104 105 err: 106 ASN1_INTEGER_free(public_key); 107 DH_free(dh); 108 return 0; 109 } 110 111 static int dh_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey) 112 { 113 DH *dh; 114 int ptype; 115 unsigned char *penc = NULL; 116 int penclen; 117 ASN1_STRING *str; 118 ASN1_INTEGER *pub_key = NULL; 119 120 dh = pkey->pkey.dh; 121 122 str = ASN1_STRING_new(); 123 if (str == NULL) { 124 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE); 125 goto err; 126 } 127 str->length = i2d_dhp(pkey, dh, &str->data); 128 if (str->length <= 0) { 129 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE); 130 goto err; 131 } 132 ptype = V_ASN1_SEQUENCE; 133 134 pub_key = BN_to_ASN1_INTEGER(dh->pub_key, NULL); 135 if (pub_key == NULL) 136 goto err; 137 138 penclen = i2d_ASN1_INTEGER(pub_key, &penc); 139 140 ASN1_INTEGER_free(pub_key); 141 142 if (penclen <= 0) { 143 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE); 144 goto err; 145 } 146 147 if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(pkey->ameth->pkey_id), 148 ptype, str, penc, penclen)) 149 return 1; 150 151 err: 152 OPENSSL_free(penc); 153 ASN1_STRING_free(str); 154 155 return 0; 156 } 157 158 /* 159 * PKCS#8 DH is defined in PKCS#11 of all places. It is similar to DH in that 160 * the AlgorithmIdentifier contains the parameters, the private key is 161 * explicitly included and the pubkey must be recalculated. 162 */ 163 164 static int dh_priv_decode(EVP_PKEY *pkey, const PKCS8_PRIV_KEY_INFO *p8) 165 { 166 int ret = 0; 167 DH *dh = ossl_dh_key_from_pkcs8(p8, NULL, NULL); 168 169 if (dh != NULL) { 170 ret = 1; 171 EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, dh); 172 } 173 174 return ret; 175 } 176 177 static int dh_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey) 178 { 179 ASN1_STRING *params = NULL; 180 ASN1_INTEGER *prkey = NULL; 181 unsigned char *dp = NULL; 182 int dplen; 183 184 params = ASN1_STRING_new(); 185 186 if (params == NULL) { 187 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE); 188 goto err; 189 } 190 191 params->length = i2d_dhp(pkey, pkey->pkey.dh, ¶ms->data); 192 if (params->length <= 0) { 193 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE); 194 goto err; 195 } 196 params->type = V_ASN1_SEQUENCE; 197 198 /* Get private key into integer */ 199 prkey = BN_to_ASN1_INTEGER(pkey->pkey.dh->priv_key, NULL); 200 201 if (prkey == NULL) { 202 ERR_raise(ERR_LIB_DH, DH_R_BN_ERROR); 203 goto err; 204 } 205 206 dplen = i2d_ASN1_INTEGER(prkey, &dp); 207 208 ASN1_STRING_clear_free(prkey); 209 210 if (dplen <= 0) { 211 ERR_raise(ERR_LIB_DH, DH_R_BN_ERROR); 212 goto err; 213 } 214 215 if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(pkey->ameth->pkey_id), 0, 216 V_ASN1_SEQUENCE, params, dp, dplen)) { 217 OPENSSL_clear_free(dp, dplen); 218 goto err; 219 } 220 return 1; 221 222 err: 223 ASN1_STRING_free(params); 224 return 0; 225 } 226 227 static int dh_param_decode(EVP_PKEY *pkey, 228 const unsigned char **pder, int derlen) 229 { 230 DH *dh; 231 232 if ((dh = d2i_dhp(pkey, pder, derlen)) == NULL) 233 return 0; 234 dh->dirty_cnt++; 235 EVP_PKEY_assign(pkey, pkey->ameth->pkey_id, dh); 236 return 1; 237 } 238 239 static int dh_param_encode(const EVP_PKEY *pkey, unsigned char **pder) 240 { 241 return i2d_dhp(pkey, pkey->pkey.dh, pder); 242 } 243 244 static int do_dh_print(BIO *bp, const DH *x, int indent, int ptype) 245 { 246 int reason = ERR_R_BUF_LIB; 247 const char *ktype = NULL; 248 BIGNUM *priv_key, *pub_key; 249 250 if (ptype == 2) 251 priv_key = x->priv_key; 252 else 253 priv_key = NULL; 254 255 if (ptype > 0) 256 pub_key = x->pub_key; 257 else 258 pub_key = NULL; 259 260 if (x->params.p == NULL || (ptype == 2 && priv_key == NULL) 261 || (ptype > 0 && pub_key == NULL)) { 262 reason = ERR_R_PASSED_NULL_PARAMETER; 263 goto err; 264 } 265 266 if (ptype == 2) 267 ktype = "DH Private-Key"; 268 else if (ptype == 1) 269 ktype = "DH Public-Key"; 270 else 271 ktype = "DH Parameters"; 272 273 if (!BIO_indent(bp, indent, 128) 274 || BIO_printf(bp, "%s: (%d bit)\n", ktype, DH_bits(x)) <= 0) 275 goto err; 276 indent += 4; 277 278 if (!ASN1_bn_print(bp, "private-key:", priv_key, NULL, indent)) 279 goto err; 280 if (!ASN1_bn_print(bp, "public-key:", pub_key, NULL, indent)) 281 goto err; 282 283 if (!ossl_ffc_params_print(bp, &x->params, indent)) 284 goto err; 285 286 if (x->length != 0) { 287 if (!BIO_indent(bp, indent, 128) 288 || BIO_printf(bp, "recommended-private-length: %d bits\n", 289 (int)x->length) <= 0) 290 goto err; 291 } 292 293 return 1; 294 295 err: 296 ERR_raise(ERR_LIB_DH, reason); 297 return 0; 298 } 299 300 static int int_dh_size(const EVP_PKEY *pkey) 301 { 302 return DH_size(pkey->pkey.dh); 303 } 304 305 static int dh_bits(const EVP_PKEY *pkey) 306 { 307 return DH_bits(pkey->pkey.dh); 308 } 309 310 static int dh_security_bits(const EVP_PKEY *pkey) 311 { 312 return DH_security_bits(pkey->pkey.dh); 313 } 314 315 static int dh_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b) 316 { 317 return ossl_ffc_params_cmp(&a->pkey.dh->params, &b->pkey.dh->params, 318 a->ameth != &ossl_dhx_asn1_meth); 319 } 320 321 static int int_dh_param_copy(DH *to, const DH *from, int is_x942) 322 { 323 if (is_x942 == -1) 324 is_x942 = (from->params.q != NULL); 325 if (!ossl_ffc_params_copy(&to->params, &from->params)) 326 return 0; 327 if (!is_x942) 328 to->length = from->length; 329 to->dirty_cnt++; 330 return 1; 331 } 332 333 DH *DHparams_dup(const DH *dh) 334 { 335 DH *ret; 336 ret = DH_new(); 337 if (ret == NULL) 338 return NULL; 339 if (!int_dh_param_copy(ret, dh, -1)) { 340 DH_free(ret); 341 return NULL; 342 } 343 return ret; 344 } 345 346 static int dh_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from) 347 { 348 if (to->pkey.dh == NULL) { 349 to->pkey.dh = DH_new(); 350 if (to->pkey.dh == NULL) 351 return 0; 352 } 353 return int_dh_param_copy(to->pkey.dh, from->pkey.dh, 354 from->ameth == &ossl_dhx_asn1_meth); 355 } 356 357 static int dh_missing_parameters(const EVP_PKEY *a) 358 { 359 return a->pkey.dh == NULL 360 || a->pkey.dh->params.p == NULL 361 || a->pkey.dh->params.g == NULL; 362 } 363 364 static int dh_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b) 365 { 366 if (dh_cmp_parameters(a, b) == 0) 367 return 0; 368 if (BN_cmp(b->pkey.dh->pub_key, a->pkey.dh->pub_key) != 0) 369 return 0; 370 else 371 return 1; 372 } 373 374 static int dh_param_print(BIO *bp, const EVP_PKEY *pkey, int indent, 375 ASN1_PCTX *ctx) 376 { 377 return do_dh_print(bp, pkey->pkey.dh, indent, 0); 378 } 379 380 static int dh_public_print(BIO *bp, const EVP_PKEY *pkey, int indent, 381 ASN1_PCTX *ctx) 382 { 383 return do_dh_print(bp, pkey->pkey.dh, indent, 1); 384 } 385 386 static int dh_private_print(BIO *bp, const EVP_PKEY *pkey, int indent, 387 ASN1_PCTX *ctx) 388 { 389 return do_dh_print(bp, pkey->pkey.dh, indent, 2); 390 } 391 392 int DHparams_print(BIO *bp, const DH *x) 393 { 394 return do_dh_print(bp, x, 4, 0); 395 } 396 397 static int dh_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2) 398 { 399 DH *dh; 400 switch (op) { 401 case ASN1_PKEY_CTRL_SET1_TLS_ENCPT: 402 /* We should only be here if we have a legacy key */ 403 if (!ossl_assert(evp_pkey_is_legacy(pkey))) 404 return 0; 405 dh = (DH *) evp_pkey_get0_DH_int(pkey); 406 if (dh == NULL) 407 return 0; 408 return ossl_dh_buf2key(dh, arg2, arg1); 409 case ASN1_PKEY_CTRL_GET1_TLS_ENCPT: 410 dh = (DH *) EVP_PKEY_get0_DH(pkey); 411 if (dh == NULL) 412 return 0; 413 return ossl_dh_key2buf(dh, arg2, 0, 1); 414 default: 415 return -2; 416 } 417 } 418 419 static int dhx_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2) 420 { 421 switch (op) { 422 default: 423 return -2; 424 } 425 426 } 427 428 static int dh_pkey_public_check(const EVP_PKEY *pkey) 429 { 430 DH *dh = pkey->pkey.dh; 431 432 if (dh->pub_key == NULL) { 433 ERR_raise(ERR_LIB_DH, DH_R_MISSING_PUBKEY); 434 return 0; 435 } 436 437 return DH_check_pub_key_ex(dh, dh->pub_key); 438 } 439 440 static int dh_pkey_param_check(const EVP_PKEY *pkey) 441 { 442 DH *dh = pkey->pkey.dh; 443 444 return DH_check_ex(dh); 445 } 446 447 static size_t dh_pkey_dirty_cnt(const EVP_PKEY *pkey) 448 { 449 return pkey->pkey.dh->dirty_cnt; 450 } 451 452 static int dh_pkey_export_to(const EVP_PKEY *from, void *to_keydata, 453 OSSL_FUNC_keymgmt_import_fn *importer, 454 OSSL_LIB_CTX *libctx, const char *propq) 455 { 456 DH *dh = from->pkey.dh; 457 OSSL_PARAM_BLD *tmpl; 458 const BIGNUM *p = DH_get0_p(dh), *g = DH_get0_g(dh), *q = DH_get0_q(dh); 459 long l = DH_get_length(dh); 460 const BIGNUM *pub_key = DH_get0_pub_key(dh); 461 const BIGNUM *priv_key = DH_get0_priv_key(dh); 462 OSSL_PARAM *params = NULL; 463 int selection = 0; 464 int rv = 0; 465 466 if (p == NULL || g == NULL) 467 return 0; 468 469 tmpl = OSSL_PARAM_BLD_new(); 470 if (tmpl == NULL) 471 return 0; 472 if (!OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_P, p) 473 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_G, g)) 474 goto err; 475 if (q != NULL) { 476 if (!OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_Q, q)) 477 goto err; 478 } 479 selection |= OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS; 480 if (l > 0) { 481 if (!OSSL_PARAM_BLD_push_long(tmpl, OSSL_PKEY_PARAM_DH_PRIV_LEN, l)) 482 goto err; 483 selection |= OSSL_KEYMGMT_SELECT_OTHER_PARAMETERS; 484 } 485 if (pub_key != NULL) { 486 if (!OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_PUB_KEY, pub_key)) 487 goto err; 488 selection |= OSSL_KEYMGMT_SELECT_PUBLIC_KEY; 489 } 490 if (priv_key != NULL) { 491 if (!OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_PRIV_KEY, 492 priv_key)) 493 goto err; 494 selection |= OSSL_KEYMGMT_SELECT_PRIVATE_KEY; 495 } 496 497 if ((params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL) 498 goto err; 499 500 /* We export, the provider imports */ 501 rv = importer(to_keydata, selection, params); 502 503 OSSL_PARAM_free(params); 504 err: 505 OSSL_PARAM_BLD_free(tmpl); 506 return rv; 507 } 508 509 static int dh_pkey_import_from_type(const OSSL_PARAM params[], void *vpctx, 510 int type) 511 { 512 EVP_PKEY_CTX *pctx = vpctx; 513 EVP_PKEY *pkey = EVP_PKEY_CTX_get0_pkey(pctx); 514 DH *dh = ossl_dh_new_ex(pctx->libctx); 515 516 if (dh == NULL) { 517 ERR_raise(ERR_LIB_DH, ERR_R_MALLOC_FAILURE); 518 return 0; 519 } 520 DH_clear_flags(dh, DH_FLAG_TYPE_MASK); 521 DH_set_flags(dh, type == EVP_PKEY_DH ? DH_FLAG_TYPE_DH : DH_FLAG_TYPE_DHX); 522 523 if (!ossl_dh_params_fromdata(dh, params) 524 || !ossl_dh_key_fromdata(dh, params, 1) 525 || !EVP_PKEY_assign(pkey, type, dh)) { 526 DH_free(dh); 527 return 0; 528 } 529 return 1; 530 } 531 532 static int dh_pkey_import_from(const OSSL_PARAM params[], void *vpctx) 533 { 534 return dh_pkey_import_from_type(params, vpctx, EVP_PKEY_DH); 535 } 536 537 static int dhx_pkey_import_from(const OSSL_PARAM params[], void *vpctx) 538 { 539 return dh_pkey_import_from_type(params, vpctx, EVP_PKEY_DHX); 540 } 541 542 static int dh_pkey_copy(EVP_PKEY *to, EVP_PKEY *from) 543 { 544 DH *dh = from->pkey.dh; 545 DH *dupkey = NULL; 546 int ret; 547 548 if (dh != NULL) { 549 dupkey = ossl_dh_dup(dh, OSSL_KEYMGMT_SELECT_ALL); 550 if (dupkey == NULL) 551 return 0; 552 } 553 554 ret = EVP_PKEY_assign(to, from->type, dupkey); 555 if (!ret) 556 DH_free(dupkey); 557 return ret; 558 } 559 560 const EVP_PKEY_ASN1_METHOD ossl_dh_asn1_meth = { 561 EVP_PKEY_DH, 562 EVP_PKEY_DH, 563 0, 564 565 "DH", 566 "OpenSSL PKCS#3 DH method", 567 568 dh_pub_decode, 569 dh_pub_encode, 570 dh_pub_cmp, 571 dh_public_print, 572 573 dh_priv_decode, 574 dh_priv_encode, 575 dh_private_print, 576 577 int_dh_size, 578 dh_bits, 579 dh_security_bits, 580 581 dh_param_decode, 582 dh_param_encode, 583 dh_missing_parameters, 584 dh_copy_parameters, 585 dh_cmp_parameters, 586 dh_param_print, 587 0, 588 589 int_dh_free, 590 dh_pkey_ctrl, 591 592 0, 0, 0, 0, 0, 593 594 0, 595 dh_pkey_public_check, 596 dh_pkey_param_check, 597 598 0, 0, 0, 0, 599 600 dh_pkey_dirty_cnt, 601 dh_pkey_export_to, 602 dh_pkey_import_from, 603 dh_pkey_copy 604 }; 605 606 const EVP_PKEY_ASN1_METHOD ossl_dhx_asn1_meth = { 607 EVP_PKEY_DHX, 608 EVP_PKEY_DHX, 609 0, 610 611 "X9.42 DH", 612 "OpenSSL X9.42 DH method", 613 614 dh_pub_decode, 615 dh_pub_encode, 616 dh_pub_cmp, 617 dh_public_print, 618 619 dh_priv_decode, 620 dh_priv_encode, 621 dh_private_print, 622 623 int_dh_size, 624 dh_bits, 625 dh_security_bits, 626 627 dh_param_decode, 628 dh_param_encode, 629 dh_missing_parameters, 630 dh_copy_parameters, 631 dh_cmp_parameters, 632 dh_param_print, 633 0, 634 635 int_dh_free, 636 dhx_pkey_ctrl, 637 638 0, 0, 0, 0, 0, 639 640 0, 641 dh_pkey_public_check, 642 dh_pkey_param_check, 643 0, 0, 0, 0, 644 dh_pkey_dirty_cnt, 645 dh_pkey_export_to, 646 dhx_pkey_import_from, 647 dh_pkey_copy 648 }; 649