1 /* 2 * Copyright 1995-2023 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 * DSA 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 "internal/cryptlib.h" 18 #include <openssl/bn.h> 19 #include "dsa_local.h" 20 #include "crypto/dsa.h" 21 22 int ossl_dsa_check_params(const DSA *dsa, int checktype, int *ret) 23 { 24 if (checktype == OSSL_KEYMGMT_VALIDATE_QUICK_CHECK) 25 return ossl_ffc_params_simple_validate(dsa->libctx, &dsa->params, 26 FFC_PARAM_TYPE_DSA, ret); 27 else 28 /* 29 * Do full FFC domain params validation according to FIPS-186-4 30 * - always in FIPS_MODULE 31 * - only if possible (i.e., seed is set) in default provider 32 */ 33 return ossl_ffc_params_full_validate(dsa->libctx, &dsa->params, 34 FFC_PARAM_TYPE_DSA, ret); 35 } 36 37 /* 38 * See SP800-56Ar3 Section 5.6.2.3.1 : FFC Full public key validation. 39 */ 40 int ossl_dsa_check_pub_key(const DSA *dsa, const BIGNUM *pub_key, int *ret) 41 { 42 return ossl_ffc_validate_public_key(&dsa->params, pub_key, ret) 43 && *ret == 0; 44 } 45 46 /* 47 * See SP800-56Ar3 Section 5.6.2.3.1 : FFC Partial public key validation. 48 * To only be used with ephemeral FFC public keys generated using the approved 49 * safe-prime groups. 50 */ 51 int ossl_dsa_check_pub_key_partial(const DSA *dsa, const BIGNUM *pub_key, int *ret) 52 { 53 return ossl_ffc_validate_public_key_partial(&dsa->params, pub_key, ret) 54 && *ret == 0; 55 } 56 57 int ossl_dsa_check_priv_key(const DSA *dsa, const BIGNUM *priv_key, int *ret) 58 { 59 *ret = 0; 60 61 return (dsa->params.q != NULL 62 && ossl_ffc_validate_private_key(dsa->params.q, priv_key, ret)); 63 } 64 65 /* 66 * FFC pairwise check from SP800-56A R3. 67 * Section 5.6.2.1.4 Owner Assurance of Pair-wise Consistency 68 */ 69 int ossl_dsa_check_pairwise(const DSA *dsa) 70 { 71 int ret = 0; 72 BN_CTX *ctx = NULL; 73 BIGNUM *pub_key = NULL; 74 75 if (dsa->params.p == NULL 76 || dsa->params.g == NULL 77 || dsa->priv_key == NULL 78 || dsa->pub_key == NULL) 79 return 0; 80 81 ctx = BN_CTX_new_ex(dsa->libctx); 82 if (ctx == NULL) 83 goto err; 84 pub_key = BN_new(); 85 if (pub_key == NULL) 86 goto err; 87 88 /* recalculate the public key = (g ^ priv) mod p */ 89 if (!ossl_dsa_generate_public_key(ctx, dsa, dsa->priv_key, pub_key)) 90 goto err; 91 /* check it matches the existing pubic_key */ 92 ret = BN_cmp(pub_key, dsa->pub_key) == 0; 93 err: 94 BN_free(pub_key); 95 BN_CTX_free(ctx); 96 return ret; 97 } 98