crypto/rsa/rsa_x931g.c

   1 /*
   2  * Copyright 1995-2021 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  * RSA low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #define OPENSSL_SUPPRESS_DEPRECATED
  15
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <time.h>
  19 #include <openssl/err.h>
  20 #include <openssl/bn.h>
  21 #include "rsa_local.h"
  22
  23 /* X9.31 RSA key derivation and generation */
  24
  25 int RSA_X931_derive_ex(RSA *rsa, BIGNUM *p1, BIGNUM *p2, BIGNUM *q1,
  26                        BIGNUM *q2, const BIGNUM *Xp1, const BIGNUM *Xp2,
  27                        const BIGNUM *Xp, const BIGNUM *Xq1, const BIGNUM *Xq2,
  28                        const BIGNUM *Xq, const BIGNUM *e, BN_GENCB *cb)
  29 {
  30     BIGNUM *r0 = NULL, *r1 = NULL, *r2 = NULL, *r3 = NULL;
  31     BN_CTX *ctx = NULL, *ctx2 = NULL;
  32     int ret = 0;
  33
  34     if (!rsa)
  35         goto err;
  36
  37     ctx = BN_CTX_new();
  38     if (ctx == NULL)
  39         goto err;
  40     BN_CTX_start(ctx);
  41
  42     r0 = BN_CTX_get(ctx);
  43     r1 = BN_CTX_get(ctx);
  44     r2 = BN_CTX_get(ctx);
  45     r3 = BN_CTX_get(ctx);
  46
  47     if (r3 == NULL)
  48         goto err;
  49     if (!rsa->e) {
  50         rsa->e = BN_dup(e);
  51         if (!rsa->e)
  52             goto err;
  53     } else {
  54         e = rsa->e;
  55     }
  56
  57     /*
  58      * If not all parameters present only calculate what we can. This allows
  59      * test programs to output selective parameters.
  60      */
  61
  62     if (Xp && rsa->p == NULL) {
  63         rsa->p = BN_new();
  64         if (rsa->p == NULL)
  65             goto err;
  66
  67         if (!BN_X931_derive_prime_ex(rsa->p, p1, p2,
  68                                      Xp, Xp1, Xp2, e, ctx, cb))
  69             goto err;
  70     }
  71
  72     if (Xq && rsa->q == NULL) {
  73         rsa->q = BN_new();
  74         if (rsa->q == NULL)
  75             goto err;
  76         if (!BN_X931_derive_prime_ex(rsa->q, q1, q2,
  77                                      Xq, Xq1, Xq2, e, ctx, cb))
  78             goto err;
  79     }
  80
  81     if (rsa->p == NULL || rsa->q == NULL) {
  82         BN_CTX_end(ctx);
  83         BN_CTX_free(ctx);
  84         return 2;
  85     }
  86
  87     /*
  88      * Since both primes are set we can now calculate all remaining
  89      * components.
  90      */
  91
  92     /* calculate n */
  93     rsa->n = BN_new();
  94     if (rsa->n == NULL)
  95         goto err;
  96     if (!BN_mul(rsa->n, rsa->p, rsa->q, ctx))
  97         goto err;
  98
  99     /* calculate d */
 100     if (!BN_sub(r1, rsa->p, BN_value_one()))
 101         goto err;               /* p-1 */
 102     if (!BN_sub(r2, rsa->q, BN_value_one()))
 103         goto err;               /* q-1 */
 104     if (!BN_mul(r0, r1, r2, ctx))
 105         goto err;               /* (p-1)(q-1) */
 106
 107     if (!BN_gcd(r3, r1, r2, ctx))
 108         goto err;
 109
 110     if (!BN_div(r0, NULL, r0, r3, ctx))
 111         goto err;               /* LCM((p-1)(q-1)) */
 112
 113     ctx2 = BN_CTX_new();
 114     if (ctx2 == NULL)
 115         goto err;
 116
 117     rsa->d = BN_mod_inverse(NULL, rsa->e, r0, ctx2); /* d */
 118     if (rsa->d == NULL)
 119         goto err;
 120
 121     /* calculate d mod (p-1) */
 122     rsa->dmp1 = BN_new();
 123     if (rsa->dmp1 == NULL)
 124         goto err;
 125     if (!BN_mod(rsa->dmp1, rsa->d, r1, ctx))
 126         goto err;
 127
 128     /* calculate d mod (q-1) */
 129     rsa->dmq1 = BN_new();
 130     if (rsa->dmq1 == NULL)
 131         goto err;
 132     if (!BN_mod(rsa->dmq1, rsa->d, r2, ctx))
 133         goto err;
 134
 135     /* calculate inverse of q mod p */
 136     rsa->iqmp = BN_mod_inverse(NULL, rsa->q, rsa->p, ctx2);
 137     if (rsa->iqmp == NULL)
 138         goto err;
 139
 140     rsa->dirty_cnt++;
 141     ret = 1;
 142  err:
 143     BN_CTX_end(ctx);
 144     BN_CTX_free(ctx);
 145     BN_CTX_free(ctx2);
 146
 147     return ret;
 148
 149 }
 150
 151 int RSA_X931_generate_key_ex(RSA *rsa, int bits, const BIGNUM *e,
 152                              BN_GENCB *cb)
 153 {
 154     int ok = 0;
 155     BIGNUM *Xp = NULL, *Xq = NULL;
 156     BN_CTX *ctx = NULL;
 157
 158     ctx = BN_CTX_new();
 159     if (ctx == NULL)
 160         goto error;
 161
 162     BN_CTX_start(ctx);
 163     Xp = BN_CTX_get(ctx);
 164     Xq = BN_CTX_get(ctx);
 165     if (Xq == NULL)
 166         goto error;
 167     if (!BN_X931_generate_Xpq(Xp, Xq, bits, ctx))
 168         goto error;
 169
 170     rsa->p = BN_new();
 171     rsa->q = BN_new();
 172     if (rsa->p == NULL || rsa->q == NULL)
 173         goto error;
 174
 175     /* Generate two primes from Xp, Xq */
 176
 177     if (!BN_X931_generate_prime_ex(rsa->p, NULL, NULL, NULL, NULL, Xp,
 178                                    e, ctx, cb))
 179         goto error;
 180
 181     if (!BN_X931_generate_prime_ex(rsa->q, NULL, NULL, NULL, NULL, Xq,
 182                                    e, ctx, cb))
 183         goto error;
 184
 185     /*
 186      * Since rsa->p and rsa->q are valid this call will just derive remaining
 187      * RSA components.
 188      */
 189
 190     if (!RSA_X931_derive_ex(rsa, NULL, NULL, NULL, NULL,
 191                             NULL, NULL, NULL, NULL, NULL, NULL, e, cb))
 192         goto error;
 193
 194     rsa->dirty_cnt++;
 195     ok = 1;
 196
 197  error:
 198     BN_CTX_end(ctx);
 199     BN_CTX_free(ctx);
 200
 201     if (ok)
 202         return 1;
 203
 204     return 0;
 205
 206 }