1/* 2 * Copyright (c) 2000-2001 Apple Computer, Inc. All Rights Reserved. 3 * 4 * The contents of this file constitute Original Code as defined in and are 5 * subject to the Apple Public Source License Version 1.2 (the 'License'). 6 * You may not use this file except in compliance with the License. Please obtain 7 * a copy of the License at http://www.apple.com/publicsource and read it before 8 * using this file. 9 * 10 * This Original Code and all software distributed under the License are 11 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESS 12 * OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, INCLUDING WITHOUT 13 * LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR 14 * PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. Please see the License for the 15 * specific language governing rights and limitations under the License. 16 */ 17 18 19/* crypto/dsa/dsa_gen.c */ 20/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 21 * All rights reserved. 22 * 23 * This package is an SSL implementation written 24 * by Eric Young (eay@cryptsoft.com). 25 * The implementation was written so as to conform with Netscapes SSL. 26 * 27 * This library is free for commercial and non-commercial use as long as 28 * the following conditions are aheared to. The following conditions 29 * apply to all code found in this distribution, be it the RC4, RSA, 30 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 31 * included with this distribution is covered by the same copyright terms 32 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 33 * 34 * Copyright remains Eric Young's, and as such any Copyright notices in 35 * the code are not to be removed. 36 * If this package is used in a product, Eric Young should be given attribution 37 * as the author of the parts of the library used. 38 * This can be in the form of a textual message at program startup or 39 * in documentation (online or textual) provided with the package. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. All advertising materials mentioning features or use of this software 50 * must display the following acknowledgement: 51 * "This product includes cryptographic software written by 52 * Eric Young (eay@cryptsoft.com)" 53 * The word 'cryptographic' can be left out if the rouines from the library 54 * being used are not cryptographic related :-). 55 * 4. If you include any Windows specific code (or a derivative thereof) from 56 * the apps directory (application code) you must include an acknowledgement: 57 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 58 * 59 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * The licence and distribution terms for any publically available version or 72 * derivative of this code cannot be changed. i.e. this code cannot simply be 73 * copied and put under another distribution licence 74 * [including the GNU Public Licence.] 75 */ 76 77#undef GENUINE_DSA 78 79#ifdef GENUINE_DSA 80/* Parameter generation follows the original release of FIPS PUB 186, 81 * Appendix 2.2 (i.e. use SHA as defined in FIPS PUB 180) */ 82#define HASH SHA 83#else 84/* Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186, 85 * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in 86 * FIPS PUB 180-1) */ 87#define HASH SHA1 88#endif 89 90#ifndef NO_SHA 91 92#include <stdio.h> 93#include <time.h> 94#include "cryptlib.h" 95#include <openssl/sha.h> 96#include <openssl/bn.h> 97#include <openssl/dsa.h> 98#include <openssl/rand.h> 99 100DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len, 101 int *counter_ret, unsigned long *h_ret, 102 void (*callback)(int, int, void *), 103 void *cb_arg) 104 { 105 int ok=0; 106 unsigned char seed[SHA_DIGEST_LENGTH]; 107 unsigned char md[SHA_DIGEST_LENGTH]; 108 unsigned char buf[SHA_DIGEST_LENGTH],buf2[SHA_DIGEST_LENGTH]; 109 BIGNUM *r0,*W,*X,*c,*test; 110 BIGNUM *g=NULL,*q=NULL,*p=NULL; 111 BN_MONT_CTX *mont=NULL; 112 int k,n=0,i,b,m=0; 113 int counter=0; 114 int r=0; 115 BN_CTX *ctx=NULL,*ctx2=NULL,*ctx3=NULL; 116 unsigned int h=2; 117 DSA *ret=NULL; 118 119 if (bits < 512) bits=512; 120 bits=(bits+63)/64*64; 121 122 if (seed_len < 20) 123 seed_in = NULL; /* seed buffer too small -- ignore */ 124 if (seed_len > 20) 125 seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED, 126 * but our internal buffers are restricted to 160 bits*/ 127 if ((seed_in != NULL) && (seed_len == 20)) 128 memcpy(seed,seed_in,seed_len); 129 130 if ((ctx=BN_CTX_new()) == NULL) goto err; 131 if ((ctx2=BN_CTX_new()) == NULL) goto err; 132 if ((ctx3=BN_CTX_new()) == NULL) goto err; 133 if ((ret=DSA_new()) == NULL) goto err; 134 135 if ((mont=BN_MONT_CTX_new()) == NULL) goto err; 136 137 BN_CTX_start(ctx2); 138 r0 = BN_CTX_get(ctx2); 139 g = BN_CTX_get(ctx2); 140 W = BN_CTX_get(ctx2); 141 q = BN_CTX_get(ctx2); 142 X = BN_CTX_get(ctx2); 143 c = BN_CTX_get(ctx2); 144 p = BN_CTX_get(ctx2); 145 test = BN_CTX_get(ctx2); 146 147 BN_lshift(test,BN_value_one(),bits-1); 148 149 for (;;) 150 { 151 for (;;) /* find q */ 152 { 153 int seed_is_random; 154 155 /* step 1 */ 156 if (callback != NULL) callback(0,m++,cb_arg); 157 158 if (!seed_len) 159 { 160 RAND_pseudo_bytes(seed,SHA_DIGEST_LENGTH); 161 seed_is_random = 1; 162 } 163 else 164 { 165 seed_is_random = 0; 166 seed_len=0; /* use random seed if 'seed_in' turns out to be bad*/ 167 } 168 memcpy(buf,seed,SHA_DIGEST_LENGTH); 169 memcpy(buf2,seed,SHA_DIGEST_LENGTH); 170 /* precompute "SEED + 1" for step 7: */ 171 for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--) 172 { 173 buf[i]++; 174 if (buf[i] != 0) break; 175 } 176 177 /* step 2 */ 178 HASH(seed,SHA_DIGEST_LENGTH,md); 179 HASH(buf,SHA_DIGEST_LENGTH,buf2); 180 for (i=0; i<SHA_DIGEST_LENGTH; i++) 181 md[i]^=buf2[i]; 182 183 /* step 3 */ 184 md[0]|=0x80; 185 md[SHA_DIGEST_LENGTH-1]|=0x01; 186 if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err; 187 188 /* step 4 */ 189 r = BN_is_prime_fasttest(q, DSS_prime_checks, callback, ctx3, cb_arg, seed_is_random); 190 if (r > 0) 191 break; 192 if (r != 0) 193 goto err; 194 195 /* do a callback call */ 196 /* step 5 */ 197 } 198 199 if (callback != NULL) callback(2,0,cb_arg); 200 if (callback != NULL) callback(3,0,cb_arg); 201 202 /* step 6 */ 203 counter=0; 204 /* "offset = 2" */ 205 206 n=(bits-1)/160; 207 b=(bits-1)-n*160; 208 209 for (;;) 210 { 211 if (callback != NULL && counter != 0) 212 callback(0,counter,cb_arg); 213 214 /* step 7 */ 215 BN_zero(W); 216 /* now 'buf' contains "SEED + offset - 1" */ 217 for (k=0; k<=n; k++) 218 { 219 /* obtain "SEED + offset + k" by incrementing: */ 220 for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--) 221 { 222 buf[i]++; 223 if (buf[i] != 0) break; 224 } 225 226 HASH(buf,SHA_DIGEST_LENGTH,md); 227 228 /* step 8 */ 229 if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0)) 230 goto err; 231 BN_lshift(r0,r0,160*k); 232 BN_add(W,W,r0); 233 } 234 235 /* more of step 8 */ 236 BN_mask_bits(W,bits-1); 237 BN_copy(X,W); /* this should be ok */ 238 BN_add(X,X,test); /* this should be ok */ 239 240 /* step 9 */ 241 BN_lshift1(r0,q); 242 BN_mod(c,X,r0,ctx); 243 BN_sub(r0,c,BN_value_one()); 244 BN_sub(p,X,r0); 245 246 /* step 10 */ 247 if (BN_cmp(p,test) >= 0) 248 { 249 /* step 11 */ 250 r = BN_is_prime_fasttest(p, DSS_prime_checks, callback, ctx3, cb_arg, 1); 251 if (r > 0) 252 goto end; /* found it */ 253 if (r != 0) 254 goto err; 255 } 256 257 /* step 13 */ 258 counter++; 259 /* "offset = offset + n + 1" */ 260 261 /* step 14 */ 262 if (counter >= 4096) break; 263 } 264 } 265end: 266 if (callback != NULL) callback(2,1,cb_arg); 267 268 /* We now need to generate g */ 269 /* Set r0=(p-1)/q */ 270 BN_sub(test,p,BN_value_one()); 271 BN_div(r0,NULL,test,q,ctx); 272 273 BN_set_word(test,h); 274 BN_MONT_CTX_set(mont,p,ctx); 275 276 for (;;) 277 { 278 /* g=test^r0%p */ 279 BN_mod_exp_mont(g,test,r0,p,ctx,mont); 280 if (!BN_is_one(g)) break; 281 BN_add(test,test,BN_value_one()); 282 h++; 283 } 284 285 if (callback != NULL) callback(3,1,cb_arg); 286 287 ok=1; 288err: 289 if (!ok) 290 { 291 if (ret != NULL) DSA_free(ret); 292 } 293 else 294 { 295 ret->p=BN_dup(p); 296 ret->q=BN_dup(q); 297 ret->g=BN_dup(g); 298 if ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20); 299 if (counter_ret != NULL) *counter_ret=counter; 300 if (h_ret != NULL) *h_ret=h; 301 } 302 if (ctx != NULL) BN_CTX_free(ctx); 303 if (ctx2 != NULL) 304 { 305 BN_CTX_end(ctx2); 306 BN_CTX_free(ctx2); 307 } 308 if (ctx3 != NULL) BN_CTX_free(ctx3); 309 if (mont != NULL) BN_MONT_CTX_free(mont); 310 return(ok?ret:NULL); 311 } 312#endif 313