1 /* 2 * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (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 #include <stdio.h> 11 #include <string.h> 12 #include <time.h> 13 #include <openssl/err.h> 14 #include <openssl/bn.h> 15 #include "rsa_local.h" 16 17 /* X9.31 RSA key derivation and generation */ 18 19 int RSA_X931_derive_ex(RSA *rsa, BIGNUM *p1, BIGNUM *p2, BIGNUM *q1, 20 BIGNUM *q2, const BIGNUM *Xp1, const BIGNUM *Xp2, 21 const BIGNUM *Xp, const BIGNUM *Xq1, const BIGNUM *Xq2, 22 const BIGNUM *Xq, const BIGNUM *e, BN_GENCB *cb) 23 { 24 BIGNUM *r0 = NULL, *r1 = NULL, *r2 = NULL, *r3 = NULL; 25 BN_CTX *ctx = NULL, *ctx2 = NULL; 26 int ret = 0; 27 28 if (!rsa) 29 goto err; 30 31 ctx = BN_CTX_new(); 32 if (ctx == NULL) 33 goto err; 34 BN_CTX_start(ctx); 35 36 r0 = BN_CTX_get(ctx); 37 r1 = BN_CTX_get(ctx); 38 r2 = BN_CTX_get(ctx); 39 r3 = BN_CTX_get(ctx); 40 41 if (r3 == NULL) 42 goto err; 43 if (!rsa->e) { 44 rsa->e = BN_dup(e); 45 if (!rsa->e) 46 goto err; 47 } else { 48 e = rsa->e; 49 } 50 51 /* 52 * If not all parameters present only calculate what we can. This allows 53 * test programs to output selective parameters. 54 */ 55 56 if (Xp && rsa->p == NULL) { 57 rsa->p = BN_new(); 58 if (rsa->p == NULL) 59 goto err; 60 61 if (!BN_X931_derive_prime_ex(rsa->p, p1, p2, 62 Xp, Xp1, Xp2, e, ctx, cb)) 63 goto err; 64 } 65 66 if (Xq && rsa->q == NULL) { 67 rsa->q = BN_new(); 68 if (rsa->q == NULL) 69 goto err; 70 if (!BN_X931_derive_prime_ex(rsa->q, q1, q2, 71 Xq, Xq1, Xq2, e, ctx, cb)) 72 goto err; 73 } 74 75 if (rsa->p == NULL || rsa->q == NULL) { 76 BN_CTX_end(ctx); 77 BN_CTX_free(ctx); 78 return 2; 79 } 80 81 /* 82 * Since both primes are set we can now calculate all remaining 83 * components. 84 */ 85 86 /* calculate n */ 87 rsa->n = BN_new(); 88 if (rsa->n == NULL) 89 goto err; 90 if (!BN_mul(rsa->n, rsa->p, rsa->q, ctx)) 91 goto err; 92 93 /* calculate d */ 94 if (!BN_sub(r1, rsa->p, BN_value_one())) 95 goto err; /* p-1 */ 96 if (!BN_sub(r2, rsa->q, BN_value_one())) 97 goto err; /* q-1 */ 98 if (!BN_mul(r0, r1, r2, ctx)) 99 goto err; /* (p-1)(q-1) */ 100 101 if (!BN_gcd(r3, r1, r2, ctx)) 102 goto err; 103 104 if (!BN_div(r0, NULL, r0, r3, ctx)) 105 goto err; /* LCM((p-1)(q-1)) */ 106 107 ctx2 = BN_CTX_new(); 108 if (ctx2 == NULL) 109 goto err; 110 111 rsa->d = BN_mod_inverse(NULL, rsa->e, r0, ctx2); /* d */ 112 if (rsa->d == NULL) 113 goto err; 114 115 /* calculate d mod (p-1) */ 116 rsa->dmp1 = BN_new(); 117 if (rsa->dmp1 == NULL) 118 goto err; 119 if (!BN_mod(rsa->dmp1, rsa->d, r1, ctx)) 120 goto err; 121 122 /* calculate d mod (q-1) */ 123 rsa->dmq1 = BN_new(); 124 if (rsa->dmq1 == NULL) 125 goto err; 126 if (!BN_mod(rsa->dmq1, rsa->d, r2, ctx)) 127 goto err; 128 129 /* calculate inverse of q mod p */ 130 rsa->iqmp = BN_mod_inverse(NULL, rsa->q, rsa->p, ctx2); 131 if (rsa->iqmp == NULL) 132 goto err; 133 134 ret = 1; 135 err: 136 BN_CTX_end(ctx); 137 BN_CTX_free(ctx); 138 BN_CTX_free(ctx2); 139 140 return ret; 141 142 } 143 144 int RSA_X931_generate_key_ex(RSA *rsa, int bits, const BIGNUM *e, 145 BN_GENCB *cb) 146 { 147 int ok = 0; 148 BIGNUM *Xp = NULL, *Xq = NULL; 149 BN_CTX *ctx = NULL; 150 151 ctx = BN_CTX_new(); 152 if (ctx == NULL) 153 goto error; 154 155 BN_CTX_start(ctx); 156 Xp = BN_CTX_get(ctx); 157 Xq = BN_CTX_get(ctx); 158 if (Xq == NULL) 159 goto error; 160 if (!BN_X931_generate_Xpq(Xp, Xq, bits, ctx)) 161 goto error; 162 163 rsa->p = BN_new(); 164 rsa->q = BN_new(); 165 if (rsa->p == NULL || rsa->q == NULL) 166 goto error; 167 168 /* Generate two primes from Xp, Xq */ 169 170 if (!BN_X931_generate_prime_ex(rsa->p, NULL, NULL, NULL, NULL, Xp, 171 e, ctx, cb)) 172 goto error; 173 174 if (!BN_X931_generate_prime_ex(rsa->q, NULL, NULL, NULL, NULL, Xq, 175 e, ctx, cb)) 176 goto error; 177 178 /* 179 * Since rsa->p and rsa->q are valid this call will just derive remaining 180 * RSA components. 181 */ 182 183 if (!RSA_X931_derive_ex(rsa, NULL, NULL, NULL, NULL, 184 NULL, NULL, NULL, NULL, NULL, NULL, e, cb)) 185 goto error; 186 187 ok = 1; 188 189 error: 190 BN_CTX_end(ctx); 191 BN_CTX_free(ctx); 192 193 if (ok) 194 return 1; 195 196 return 0; 197 198 } 199