crypto/rsa/rsa_chk.c

   1 /*
   2  * Copyright 1999-2023 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  * RSA 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/bn.h>
  17 #include <openssl/err.h>
  18 #include "crypto/rsa.h"
  19 #include "rsa_local.h"
  20
  21 #ifndef FIPS_MODULE
  22 static int rsa_validate_keypair_multiprime(const RSA *key, BN_GENCB *cb)
  23 {
  24     BIGNUM *i, *j, *k, *l, *m;
  25     BN_CTX *ctx;
  26     int ret = 1, ex_primes = 0, idx;
  27     RSA_PRIME_INFO *pinfo;
  28
  29     if (key->p == NULL || key->q == NULL || key->n == NULL
  30             || key->e == NULL || key->d == NULL) {
  31         ERR_raise(ERR_LIB_RSA, RSA_R_VALUE_MISSING);
  32         return 0;
  33     }
  34
  35     /* multi-prime? */
  36     if (key->version == RSA_ASN1_VERSION_MULTI) {
  37         ex_primes = sk_RSA_PRIME_INFO_num(key->prime_infos);
  38         if (ex_primes <= 0
  39                 || (ex_primes + 2) > ossl_rsa_multip_cap(BN_num_bits(key->n))) {
  40             ERR_raise(ERR_LIB_RSA, RSA_R_INVALID_MULTI_PRIME_KEY);
  41             return 0;
  42         }
  43     }
  44
  45     i = BN_new();
  46     j = BN_new();
  47     k = BN_new();
  48     l = BN_new();
  49     m = BN_new();
  50     ctx = BN_CTX_new_ex(key->libctx);
  51     if (i == NULL || j == NULL || k == NULL || l == NULL
  52             || m == NULL || ctx == NULL) {
  53         ret = -1;
  54         ERR_raise(ERR_LIB_RSA, ERR_R_BN_LIB);
  55         goto err;
  56     }
  57
  58     if (BN_is_one(key->e)) {
  59         ret = 0;
  60         ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE);
  61     }
  62     if (!BN_is_odd(key->e)) {
  63         ret = 0;
  64         ERR_raise(ERR_LIB_RSA, RSA_R_BAD_E_VALUE);
  65     }
  66
  67     /* p prime? */
  68     if (BN_check_prime(key->p, ctx, cb) != 1) {
  69         ret = 0;
  70         ERR_raise(ERR_LIB_RSA, RSA_R_P_NOT_PRIME);
  71     }
  72
  73     /* q prime? */
  74     if (BN_check_prime(key->q, ctx, cb) != 1) {
  75         ret = 0;
  76         ERR_raise(ERR_LIB_RSA, RSA_R_Q_NOT_PRIME);
  77     }
  78
  79     /* r_i prime? */
  80     for (idx = 0; idx < ex_primes; idx++) {
  81         pinfo = sk_RSA_PRIME_INFO_value(key->prime_infos, idx);
  82         if (BN_check_prime(pinfo->r, ctx, cb) != 1) {
  83             ret = 0;
  84             ERR_raise(ERR_LIB_RSA, RSA_R_MP_R_NOT_PRIME);
  85         }
  86     }
  87
  88     /* n = p*q * r_3...r_i? */
  89     if (!BN_mul(i, key->p, key->q, ctx)) {
  90         ret = -1;
  91         goto err;
  92     }
  93     for (idx = 0; idx < ex_primes; idx++) {
  94         pinfo = sk_RSA_PRIME_INFO_value(key->prime_infos, idx);
  95         if (!BN_mul(i, i, pinfo->r, ctx)) {
  96             ret = -1;
  97             goto err;
  98         }
  99     }
 100     if (BN_cmp(i, key->n) != 0) {
 101         ret = 0;
 102         if (ex_primes)
 103             ERR_raise(ERR_LIB_RSA, RSA_R_N_DOES_NOT_EQUAL_PRODUCT_OF_PRIMES);
 104         else
 105             ERR_raise(ERR_LIB_RSA, RSA_R_N_DOES_NOT_EQUAL_P_Q);
 106     }
 107
 108     /* d*e = 1  mod \lambda(n)? */
 109     if (!BN_sub(i, key->p, BN_value_one())) {
 110         ret = -1;
 111         goto err;
 112     }
 113     if (!BN_sub(j, key->q, BN_value_one())) {
 114         ret = -1;
 115         goto err;
 116     }
 117
 118     /* now compute k = \lambda(n) = LCM(i, j, r_3 - 1...) */
 119     if (!BN_mul(l, i, j, ctx)) {
 120         ret = -1;
 121         goto err;
 122     }
 123     if (!BN_gcd(m, i, j, ctx)) {
 124         ret = -1;
 125         goto err;
 126     }
 127     if (!BN_div(m, NULL, l, m, ctx)) { /* remainder is 0 */
 128         ret = -1;
 129         goto err;
 130     }
 131     for (idx = 0; idx < ex_primes; idx++) {
 132         pinfo = sk_RSA_PRIME_INFO_value(key->prime_infos, idx);
 133         if (!BN_sub(k, pinfo->r, BN_value_one())) {
 134             ret = -1;
 135             goto err;
 136         }
 137         if (!BN_mul(l, m, k, ctx)) {
 138             ret = -1;
 139             goto err;
 140         }
 141         if (!BN_gcd(m, m, k, ctx)) {
 142             ret = -1;
 143             goto err;
 144         }
 145         if (!BN_div(m, NULL, l, m, ctx)) { /* remainder is 0 */
 146             ret = -1;
 147             goto err;
 148         }
 149     }
 150     if (!BN_mod_mul(i, key->d, key->e, m, ctx)) {
 151         ret = -1;
 152         goto err;
 153     }
 154
 155     if (!BN_is_one(i)) {
 156         ret = 0;
 157         ERR_raise(ERR_LIB_RSA, RSA_R_D_E_NOT_CONGRUENT_TO_1);
 158     }
 159
 160     if (key->dmp1 != NULL && key->dmq1 != NULL && key->iqmp != NULL) {
 161         /* dmp1 = d mod (p-1)? */
 162         if (!BN_sub(i, key->p, BN_value_one())) {
 163             ret = -1;
 164             goto err;
 165         }
 166         if (!BN_mod(j, key->d, i, ctx)) {
 167             ret = -1;
 168             goto err;
 169         }
 170         if (BN_cmp(j, key->dmp1) != 0) {
 171             ret = 0;
 172             ERR_raise(ERR_LIB_RSA, RSA_R_DMP1_NOT_CONGRUENT_TO_D);
 173         }
 174
 175         /* dmq1 = d mod (q-1)? */
 176         if (!BN_sub(i, key->q, BN_value_one())) {
 177             ret = -1;
 178             goto err;
 179         }
 180         if (!BN_mod(j, key->d, i, ctx)) {
 181             ret = -1;
 182             goto err;
 183         }
 184         if (BN_cmp(j, key->dmq1) != 0) {
 185             ret = 0;
 186             ERR_raise(ERR_LIB_RSA, RSA_R_DMQ1_NOT_CONGRUENT_TO_D);
 187         }
 188
 189         /* iqmp = q^-1 mod p? */
 190         if (!BN_mod_inverse(i, key->q, key->p, ctx)) {
 191             ret = -1;
 192             goto err;
 193         }
 194         if (BN_cmp(i, key->iqmp) != 0) {
 195             ret = 0;
 196             ERR_raise(ERR_LIB_RSA, RSA_R_IQMP_NOT_INVERSE_OF_Q);
 197         }
 198     }
 199
 200     for (idx = 0; idx < ex_primes; idx++) {
 201         pinfo = sk_RSA_PRIME_INFO_value(key->prime_infos, idx);
 202         /* d_i = d mod (r_i - 1)? */
 203         if (!BN_sub(i, pinfo->r, BN_value_one())) {
 204             ret = -1;
 205             goto err;
 206         }
 207         if (!BN_mod(j, key->d, i, ctx)) {
 208             ret = -1;
 209             goto err;
 210         }
 211         if (BN_cmp(j, pinfo->d) != 0) {
 212             ret = 0;
 213             ERR_raise(ERR_LIB_RSA, RSA_R_MP_EXPONENT_NOT_CONGRUENT_TO_D);
 214         }
 215         /* t_i = R_i ^ -1 mod r_i ? */
 216         if (!BN_mod_inverse(i, pinfo->pp, pinfo->r, ctx)) {
 217             ret = -1;
 218             goto err;
 219         }
 220         if (BN_cmp(i, pinfo->t) != 0) {
 221             ret = 0;
 222             ERR_raise(ERR_LIB_RSA, RSA_R_MP_COEFFICIENT_NOT_INVERSE_OF_R);
 223         }
 224     }
 225
 226  err:
 227     BN_free(i);
 228     BN_free(j);
 229     BN_free(k);
 230     BN_free(l);
 231     BN_free(m);
 232     BN_CTX_free(ctx);
 233     return ret;
 234 }
 235 #endif /* FIPS_MODULE */
 236
 237 int ossl_rsa_validate_public(const RSA *key)
 238 {
 239     return ossl_rsa_sp800_56b_check_public(key);
 240 }
 241
 242 int ossl_rsa_validate_private(const RSA *key)
 243 {
 244     return ossl_rsa_sp800_56b_check_private(key);
 245 }
 246
 247 int ossl_rsa_validate_pairwise(const RSA *key)
 248 {
 249 #ifdef FIPS_MODULE
 250     return ossl_rsa_sp800_56b_check_keypair(key, NULL, -1, RSA_bits(key));
 251 #else
 252     return rsa_validate_keypair_multiprime(key, NULL) > 0;
 253 #endif
 254 }
 255
 256 int RSA_check_key(const RSA *key)
 257 {
 258     return RSA_check_key_ex(key, NULL);
 259 }
 260
 261 int RSA_check_key_ex(const RSA *key, BN_GENCB *cb)
 262 {
 263 #ifdef FIPS_MODULE
 264     return ossl_rsa_validate_public(key)
 265            && ossl_rsa_validate_private(key)
 266            && ossl_rsa_validate_pairwise(key);
 267 #else
 268     return rsa_validate_keypair_multiprime(key, cb);
 269 #endif /* FIPS_MODULE */
 270 }