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
rsa_validate_keypair_multiprime(const RSA * key,BN_GENCB * cb)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
ossl_rsa_validate_public(const RSA * key)237 int ossl_rsa_validate_public(const RSA *key)
238 {
239 return ossl_rsa_sp800_56b_check_public(key);
240 }
241
ossl_rsa_validate_private(const RSA * key)242 int ossl_rsa_validate_private(const RSA *key)
243 {
244 return ossl_rsa_sp800_56b_check_private(key);
245 }
246
ossl_rsa_validate_pairwise(const RSA * key)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
RSA_check_key(const RSA * key)256 int RSA_check_key(const RSA *key)
257 {
258 return RSA_check_key_ex(key, NULL);
259 }
260
RSA_check_key_ex(const RSA * key,BN_GENCB * cb)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 }
271
