1 /* 2 * Copyright 2020-2021 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 <openssl/core_names.h> 17 #include <openssl/err.h> 18 #ifndef FIPS_MODULE 19 # include <openssl/x509.h> 20 #endif 21 #include "crypto/dsa.h" 22 #include "dsa_local.h" 23 24 /* 25 * The intention with the "backend" source file is to offer backend support 26 * for legacy backends (EVP_PKEY_ASN1_METHOD and EVP_PKEY_METHOD) and provider 27 * implementations alike. 28 */ 29 ossl_dsa_key_fromdata(DSA * dsa,const OSSL_PARAM params[])30 int ossl_dsa_key_fromdata(DSA *dsa, const OSSL_PARAM params[]) 31 { 32 const OSSL_PARAM *param_priv_key, *param_pub_key; 33 BIGNUM *priv_key = NULL, *pub_key = NULL; 34 35 if (dsa == NULL) 36 return 0; 37 38 param_priv_key = 39 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PRIV_KEY); 40 param_pub_key = 41 OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PUB_KEY); 42 43 /* It's ok if neither half is present */ 44 if (param_priv_key == NULL && param_pub_key == NULL) 45 return 1; 46 47 if (param_pub_key != NULL && !OSSL_PARAM_get_BN(param_pub_key, &pub_key)) 48 goto err; 49 if (param_priv_key != NULL && !OSSL_PARAM_get_BN(param_priv_key, &priv_key)) 50 goto err; 51 52 if (!DSA_set0_key(dsa, pub_key, priv_key)) 53 goto err; 54 55 return 1; 56 57 err: 58 BN_clear_free(priv_key); 59 BN_free(pub_key); 60 return 0; 61 } 62 ossl_dsa_is_foreign(const DSA * dsa)63 int ossl_dsa_is_foreign(const DSA *dsa) 64 { 65 #ifndef FIPS_MODULE 66 if (dsa->engine != NULL || DSA_get_method((DSA *)dsa) != DSA_OpenSSL()) 67 return 1; 68 #endif 69 return 0; 70 } 71 dsa_bn_dup_check(BIGNUM ** out,const BIGNUM * f)72 static ossl_inline int dsa_bn_dup_check(BIGNUM **out, const BIGNUM *f) 73 { 74 if (f != NULL && (*out = BN_dup(f)) == NULL) 75 return 0; 76 return 1; 77 } 78 ossl_dsa_dup(const DSA * dsa,int selection)79 DSA *ossl_dsa_dup(const DSA *dsa, int selection) 80 { 81 DSA *dupkey = NULL; 82 83 /* Do not try to duplicate foreign DSA keys */ 84 if (ossl_dsa_is_foreign(dsa)) 85 return NULL; 86 87 if ((dupkey = ossl_dsa_new(dsa->libctx)) == NULL) 88 return NULL; 89 90 if ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) != 0 91 && !ossl_ffc_params_copy(&dupkey->params, &dsa->params)) 92 goto err; 93 94 dupkey->flags = dsa->flags; 95 96 if ((selection & OSSL_KEYMGMT_SELECT_PUBLIC_KEY) != 0 97 && ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0 98 || !dsa_bn_dup_check(&dupkey->pub_key, dsa->pub_key))) 99 goto err; 100 101 if ((selection & OSSL_KEYMGMT_SELECT_PRIVATE_KEY) != 0 102 && ((selection & OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS) == 0 103 || !dsa_bn_dup_check(&dupkey->priv_key, dsa->priv_key))) 104 goto err; 105 106 #ifndef FIPS_MODULE 107 if (!CRYPTO_dup_ex_data(CRYPTO_EX_INDEX_DSA, 108 &dupkey->ex_data, &dsa->ex_data)) 109 goto err; 110 #endif 111 112 return dupkey; 113 114 err: 115 DSA_free(dupkey); 116 return NULL; 117 } 118 119 #ifndef FIPS_MODULE ossl_dsa_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO * p8inf,OSSL_LIB_CTX * libctx,const char * propq)120 DSA *ossl_dsa_key_from_pkcs8(const PKCS8_PRIV_KEY_INFO *p8inf, 121 OSSL_LIB_CTX *libctx, const char *propq) 122 { 123 const unsigned char *p, *pm; 124 int pklen, pmlen; 125 int ptype; 126 const void *pval; 127 const ASN1_STRING *pstr; 128 const X509_ALGOR *palg; 129 ASN1_INTEGER *privkey = NULL; 130 const BIGNUM *dsa_p, *dsa_g; 131 BIGNUM *dsa_pubkey = NULL, *dsa_privkey = NULL; 132 BN_CTX *ctx = NULL; 133 134 DSA *dsa = NULL; 135 136 if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8inf)) 137 return 0; 138 X509_ALGOR_get0(NULL, &ptype, &pval, palg); 139 140 if ((privkey = d2i_ASN1_INTEGER(NULL, &p, pklen)) == NULL) 141 goto decerr; 142 if (privkey->type == V_ASN1_NEG_INTEGER || ptype != V_ASN1_SEQUENCE) 143 goto decerr; 144 145 pstr = pval; 146 pm = pstr->data; 147 pmlen = pstr->length; 148 if ((dsa = d2i_DSAparams(NULL, &pm, pmlen)) == NULL) 149 goto decerr; 150 /* We have parameters now set private key */ 151 if ((dsa_privkey = BN_secure_new()) == NULL 152 || !ASN1_INTEGER_to_BN(privkey, dsa_privkey)) { 153 ERR_raise(ERR_LIB_DSA, DSA_R_BN_ERROR); 154 goto dsaerr; 155 } 156 /* Calculate public key */ 157 if ((dsa_pubkey = BN_new()) == NULL) { 158 ERR_raise(ERR_LIB_DSA, ERR_R_MALLOC_FAILURE); 159 goto dsaerr; 160 } 161 if ((ctx = BN_CTX_new()) == NULL) { 162 ERR_raise(ERR_LIB_DSA, ERR_R_MALLOC_FAILURE); 163 goto dsaerr; 164 } 165 166 dsa_p = DSA_get0_p(dsa); 167 dsa_g = DSA_get0_g(dsa); 168 BN_set_flags(dsa_privkey, BN_FLG_CONSTTIME); 169 if (!BN_mod_exp(dsa_pubkey, dsa_g, dsa_privkey, dsa_p, ctx)) { 170 ERR_raise(ERR_LIB_DSA, DSA_R_BN_ERROR); 171 goto dsaerr; 172 } 173 DSA_set0_key(dsa, dsa_pubkey, dsa_privkey); 174 175 goto done; 176 177 decerr: 178 ERR_raise(ERR_LIB_DSA, DSA_R_DECODE_ERROR); 179 dsaerr: 180 BN_free(dsa_privkey); 181 BN_free(dsa_pubkey); 182 DSA_free(dsa); 183 dsa = NULL; 184 done: 185 BN_CTX_free(ctx); 186 ASN1_STRING_clear_free(privkey); 187 return dsa; 188 } 189 #endif 190