1 /* crypto/rsa/rsa_gen.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 #include <stdio.h> 60 #include <time.h> 61 #include "cryptlib.h" 62 #include <openssl/bn.h> 63 #include <openssl/rsa.h> 64 65 RSA *RSA_generate_key(int bits, unsigned long e_value, 66 void (*callback)(int,int,void *), void *cb_arg) 67 { 68 RSA *rsa=NULL; 69 BIGNUM *r0=NULL,*r1=NULL,*r2=NULL,*r3=NULL,*tmp; 70 int bitsp,bitsq,ok= -1,n=0,i; 71 BN_CTX *ctx=NULL,*ctx2=NULL; 72 73 ctx=BN_CTX_new(); 74 if (ctx == NULL) goto err; 75 ctx2=BN_CTX_new(); 76 if (ctx2 == NULL) goto err; 77 BN_CTX_start(ctx); 78 r0 = BN_CTX_get(ctx); 79 r1 = BN_CTX_get(ctx); 80 r2 = BN_CTX_get(ctx); 81 r3 = BN_CTX_get(ctx); 82 if (r3 == NULL) goto err; 83 84 bitsp=(bits+1)/2; 85 bitsq=bits-bitsp; 86 rsa=RSA_new(); 87 if (rsa == NULL) goto err; 88 89 /* set e */ 90 rsa->e=BN_new(); 91 if (rsa->e == NULL) goto err; 92 93 #if 1 94 /* The problem is when building with 8, 16, or 32 BN_ULONG, 95 * unsigned long can be larger */ 96 for (i=0; i<sizeof(unsigned long)*8; i++) 97 { 98 if (e_value & (1UL<<i)) 99 BN_set_bit(rsa->e,i); 100 } 101 #else 102 if (!BN_set_word(rsa->e,e_value)) goto err; 103 #endif 104 105 /* generate p and q */ 106 for (;;) 107 { 108 rsa->p=BN_generate_prime(NULL,bitsp,0,NULL,NULL,callback,cb_arg); 109 if (rsa->p == NULL) goto err; 110 if (!BN_sub(r2,rsa->p,BN_value_one())) goto err; 111 if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err; 112 if (BN_is_one(r1)) break; 113 if (callback != NULL) callback(2,n++,cb_arg); 114 BN_free(rsa->p); 115 } 116 if (callback != NULL) callback(3,0,cb_arg); 117 for (;;) 118 { 119 rsa->q=BN_generate_prime(NULL,bitsq,0,NULL,NULL,callback,cb_arg); 120 if (rsa->q == NULL) goto err; 121 if (!BN_sub(r2,rsa->q,BN_value_one())) goto err; 122 if (!BN_gcd(r1,r2,rsa->e,ctx)) goto err; 123 if (BN_is_one(r1) && (BN_cmp(rsa->p,rsa->q) != 0)) 124 break; 125 if (callback != NULL) callback(2,n++,cb_arg); 126 BN_free(rsa->q); 127 } 128 if (callback != NULL) callback(3,1,cb_arg); 129 if (BN_cmp(rsa->p,rsa->q) < 0) 130 { 131 tmp=rsa->p; 132 rsa->p=rsa->q; 133 rsa->q=tmp; 134 } 135 136 /* calculate n */ 137 rsa->n=BN_new(); 138 if (rsa->n == NULL) goto err; 139 if (!BN_mul(rsa->n,rsa->p,rsa->q,ctx)) goto err; 140 141 /* calculate d */ 142 if (!BN_sub(r1,rsa->p,BN_value_one())) goto err; /* p-1 */ 143 if (!BN_sub(r2,rsa->q,BN_value_one())) goto err; /* q-1 */ 144 if (!BN_mul(r0,r1,r2,ctx)) goto err; /* (p-1)(q-1) */ 145 146 /* should not be needed, since gcd(p-1,e) == 1 and gcd(q-1,e) == 1 */ 147 /* for (;;) 148 { 149 if (!BN_gcd(r3,r0,rsa->e,ctx)) goto err; 150 if (BN_is_one(r3)) break; 151 152 if (1) 153 { 154 if (!BN_add_word(rsa->e,2L)) goto err; 155 continue; 156 } 157 RSAerr(RSA_F_RSA_GENERATE_KEY,RSA_R_BAD_E_VALUE); 158 goto err; 159 } 160 */ 161 rsa->d=BN_mod_inverse(NULL,rsa->e,r0,ctx2); /* d */ 162 if (rsa->d == NULL) goto err; 163 164 /* calculate d mod (p-1) */ 165 rsa->dmp1=BN_new(); 166 if (rsa->dmp1 == NULL) goto err; 167 if (!BN_mod(rsa->dmp1,rsa->d,r1,ctx)) goto err; 168 169 /* calculate d mod (q-1) */ 170 rsa->dmq1=BN_new(); 171 if (rsa->dmq1 == NULL) goto err; 172 if (!BN_mod(rsa->dmq1,rsa->d,r2,ctx)) goto err; 173 174 /* calculate inverse of q mod p */ 175 rsa->iqmp=BN_mod_inverse(NULL,rsa->q,rsa->p,ctx2); 176 if (rsa->iqmp == NULL) goto err; 177 178 ok=1; 179 err: 180 if (ok == -1) 181 { 182 RSAerr(RSA_F_RSA_GENERATE_KEY,ERR_LIB_BN); 183 ok=0; 184 } 185 BN_CTX_end(ctx); 186 BN_CTX_free(ctx); 187 BN_CTX_free(ctx2); 188 189 if (!ok) 190 { 191 if (rsa != NULL) RSA_free(rsa); 192 return(NULL); 193 } 194 else 195 return(rsa); 196 } 197 198