1*0Sstevel@tonic-gate /* crypto/dsa/dsa_gen.c */ 2*0Sstevel@tonic-gate /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3*0Sstevel@tonic-gate * All rights reserved. 4*0Sstevel@tonic-gate * 5*0Sstevel@tonic-gate * This package is an SSL implementation written 6*0Sstevel@tonic-gate * by Eric Young (eay@cryptsoft.com). 7*0Sstevel@tonic-gate * The implementation was written so as to conform with Netscapes SSL. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * This library is free for commercial and non-commercial use as long as 10*0Sstevel@tonic-gate * the following conditions are aheared to. The following conditions 11*0Sstevel@tonic-gate * apply to all code found in this distribution, be it the RC4, RSA, 12*0Sstevel@tonic-gate * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13*0Sstevel@tonic-gate * included with this distribution is covered by the same copyright terms 14*0Sstevel@tonic-gate * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15*0Sstevel@tonic-gate * 16*0Sstevel@tonic-gate * Copyright remains Eric Young's, and as such any Copyright notices in 17*0Sstevel@tonic-gate * the code are not to be removed. 18*0Sstevel@tonic-gate * If this package is used in a product, Eric Young should be given attribution 19*0Sstevel@tonic-gate * as the author of the parts of the library used. 20*0Sstevel@tonic-gate * This can be in the form of a textual message at program startup or 21*0Sstevel@tonic-gate * in documentation (online or textual) provided with the package. 22*0Sstevel@tonic-gate * 23*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without 24*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions 25*0Sstevel@tonic-gate * are met: 26*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the copyright 27*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer. 28*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright 29*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the 30*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution. 31*0Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software 32*0Sstevel@tonic-gate * must display the following acknowledgement: 33*0Sstevel@tonic-gate * "This product includes cryptographic software written by 34*0Sstevel@tonic-gate * Eric Young (eay@cryptsoft.com)" 35*0Sstevel@tonic-gate * The word 'cryptographic' can be left out if the rouines from the library 36*0Sstevel@tonic-gate * being used are not cryptographic related :-). 37*0Sstevel@tonic-gate * 4. If you include any Windows specific code (or a derivative thereof) from 38*0Sstevel@tonic-gate * the apps directory (application code) you must include an acknowledgement: 39*0Sstevel@tonic-gate * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40*0Sstevel@tonic-gate * 41*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42*0Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43*0Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44*0Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45*0Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46*0Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47*0Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48*0Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49*0Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50*0Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51*0Sstevel@tonic-gate * SUCH DAMAGE. 52*0Sstevel@tonic-gate * 53*0Sstevel@tonic-gate * The licence and distribution terms for any publically available version or 54*0Sstevel@tonic-gate * derivative of this code cannot be changed. i.e. this code cannot simply be 55*0Sstevel@tonic-gate * copied and put under another distribution licence 56*0Sstevel@tonic-gate * [including the GNU Public Licence.] 57*0Sstevel@tonic-gate */ 58*0Sstevel@tonic-gate 59*0Sstevel@tonic-gate #undef GENUINE_DSA 60*0Sstevel@tonic-gate 61*0Sstevel@tonic-gate #ifdef GENUINE_DSA 62*0Sstevel@tonic-gate /* Parameter generation follows the original release of FIPS PUB 186, 63*0Sstevel@tonic-gate * Appendix 2.2 (i.e. use SHA as defined in FIPS PUB 180) */ 64*0Sstevel@tonic-gate #define HASH EVP_sha() 65*0Sstevel@tonic-gate #else 66*0Sstevel@tonic-gate /* Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186, 67*0Sstevel@tonic-gate * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in 68*0Sstevel@tonic-gate * FIPS PUB 180-1) */ 69*0Sstevel@tonic-gate #define HASH EVP_sha1() 70*0Sstevel@tonic-gate #endif 71*0Sstevel@tonic-gate 72*0Sstevel@tonic-gate #ifndef OPENSSL_NO_SHA 73*0Sstevel@tonic-gate 74*0Sstevel@tonic-gate #include <stdio.h> 75*0Sstevel@tonic-gate #include <time.h> 76*0Sstevel@tonic-gate #include "cryptlib.h" 77*0Sstevel@tonic-gate #include <openssl/evp.h> 78*0Sstevel@tonic-gate #include <openssl/bn.h> 79*0Sstevel@tonic-gate #include <openssl/dsa.h> 80*0Sstevel@tonic-gate #include <openssl/rand.h> 81*0Sstevel@tonic-gate #include <openssl/sha.h> 82*0Sstevel@tonic-gate 83*0Sstevel@tonic-gate DSA *DSA_generate_parameters(int bits, 84*0Sstevel@tonic-gate unsigned char *seed_in, int seed_len, 85*0Sstevel@tonic-gate int *counter_ret, unsigned long *h_ret, 86*0Sstevel@tonic-gate void (*callback)(int, int, void *), 87*0Sstevel@tonic-gate void *cb_arg) 88*0Sstevel@tonic-gate { 89*0Sstevel@tonic-gate int ok=0; 90*0Sstevel@tonic-gate unsigned char seed[SHA_DIGEST_LENGTH]; 91*0Sstevel@tonic-gate unsigned char md[SHA_DIGEST_LENGTH]; 92*0Sstevel@tonic-gate unsigned char buf[SHA_DIGEST_LENGTH],buf2[SHA_DIGEST_LENGTH]; 93*0Sstevel@tonic-gate BIGNUM *r0,*W,*X,*c,*test; 94*0Sstevel@tonic-gate BIGNUM *g=NULL,*q=NULL,*p=NULL; 95*0Sstevel@tonic-gate BN_MONT_CTX *mont=NULL; 96*0Sstevel@tonic-gate int k,n=0,i,b,m=0; 97*0Sstevel@tonic-gate int counter=0; 98*0Sstevel@tonic-gate int r=0; 99*0Sstevel@tonic-gate BN_CTX *ctx=NULL,*ctx2=NULL,*ctx3=NULL; 100*0Sstevel@tonic-gate unsigned int h=2; 101*0Sstevel@tonic-gate DSA *ret=NULL; 102*0Sstevel@tonic-gate 103*0Sstevel@tonic-gate if (bits < 512) bits=512; 104*0Sstevel@tonic-gate bits=(bits+63)/64*64; 105*0Sstevel@tonic-gate 106*0Sstevel@tonic-gate if (seed_len < 20) 107*0Sstevel@tonic-gate seed_in = NULL; /* seed buffer too small -- ignore */ 108*0Sstevel@tonic-gate if (seed_len > 20) 109*0Sstevel@tonic-gate seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED, 110*0Sstevel@tonic-gate * but our internal buffers are restricted to 160 bits*/ 111*0Sstevel@tonic-gate if ((seed_in != NULL) && (seed_len == 20)) 112*0Sstevel@tonic-gate memcpy(seed,seed_in,seed_len); 113*0Sstevel@tonic-gate 114*0Sstevel@tonic-gate if ((ctx=BN_CTX_new()) == NULL) goto err; 115*0Sstevel@tonic-gate if ((ctx2=BN_CTX_new()) == NULL) goto err; 116*0Sstevel@tonic-gate if ((ctx3=BN_CTX_new()) == NULL) goto err; 117*0Sstevel@tonic-gate if ((ret=DSA_new()) == NULL) goto err; 118*0Sstevel@tonic-gate 119*0Sstevel@tonic-gate if ((mont=BN_MONT_CTX_new()) == NULL) goto err; 120*0Sstevel@tonic-gate 121*0Sstevel@tonic-gate BN_CTX_start(ctx2); 122*0Sstevel@tonic-gate r0 = BN_CTX_get(ctx2); 123*0Sstevel@tonic-gate g = BN_CTX_get(ctx2); 124*0Sstevel@tonic-gate W = BN_CTX_get(ctx2); 125*0Sstevel@tonic-gate q = BN_CTX_get(ctx2); 126*0Sstevel@tonic-gate X = BN_CTX_get(ctx2); 127*0Sstevel@tonic-gate c = BN_CTX_get(ctx2); 128*0Sstevel@tonic-gate p = BN_CTX_get(ctx2); 129*0Sstevel@tonic-gate test = BN_CTX_get(ctx2); 130*0Sstevel@tonic-gate 131*0Sstevel@tonic-gate BN_lshift(test,BN_value_one(),bits-1); 132*0Sstevel@tonic-gate 133*0Sstevel@tonic-gate for (;;) 134*0Sstevel@tonic-gate { 135*0Sstevel@tonic-gate for (;;) /* find q */ 136*0Sstevel@tonic-gate { 137*0Sstevel@tonic-gate int seed_is_random; 138*0Sstevel@tonic-gate 139*0Sstevel@tonic-gate /* step 1 */ 140*0Sstevel@tonic-gate if (callback != NULL) callback(0,m++,cb_arg); 141*0Sstevel@tonic-gate 142*0Sstevel@tonic-gate if (!seed_len) 143*0Sstevel@tonic-gate { 144*0Sstevel@tonic-gate RAND_pseudo_bytes(seed,SHA_DIGEST_LENGTH); 145*0Sstevel@tonic-gate seed_is_random = 1; 146*0Sstevel@tonic-gate } 147*0Sstevel@tonic-gate else 148*0Sstevel@tonic-gate { 149*0Sstevel@tonic-gate seed_is_random = 0; 150*0Sstevel@tonic-gate seed_len=0; /* use random seed if 'seed_in' turns out to be bad*/ 151*0Sstevel@tonic-gate } 152*0Sstevel@tonic-gate memcpy(buf,seed,SHA_DIGEST_LENGTH); 153*0Sstevel@tonic-gate memcpy(buf2,seed,SHA_DIGEST_LENGTH); 154*0Sstevel@tonic-gate /* precompute "SEED + 1" for step 7: */ 155*0Sstevel@tonic-gate for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--) 156*0Sstevel@tonic-gate { 157*0Sstevel@tonic-gate buf[i]++; 158*0Sstevel@tonic-gate if (buf[i] != 0) break; 159*0Sstevel@tonic-gate } 160*0Sstevel@tonic-gate 161*0Sstevel@tonic-gate /* step 2 */ 162*0Sstevel@tonic-gate EVP_Digest(seed,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL); 163*0Sstevel@tonic-gate EVP_Digest(buf,SHA_DIGEST_LENGTH,buf2,NULL,HASH, NULL); 164*0Sstevel@tonic-gate for (i=0; i<SHA_DIGEST_LENGTH; i++) 165*0Sstevel@tonic-gate md[i]^=buf2[i]; 166*0Sstevel@tonic-gate 167*0Sstevel@tonic-gate /* step 3 */ 168*0Sstevel@tonic-gate md[0]|=0x80; 169*0Sstevel@tonic-gate md[SHA_DIGEST_LENGTH-1]|=0x01; 170*0Sstevel@tonic-gate if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err; 171*0Sstevel@tonic-gate 172*0Sstevel@tonic-gate /* step 4 */ 173*0Sstevel@tonic-gate r = BN_is_prime_fasttest(q, DSS_prime_checks, callback, ctx3, cb_arg, seed_is_random); 174*0Sstevel@tonic-gate if (r > 0) 175*0Sstevel@tonic-gate break; 176*0Sstevel@tonic-gate if (r != 0) 177*0Sstevel@tonic-gate goto err; 178*0Sstevel@tonic-gate 179*0Sstevel@tonic-gate /* do a callback call */ 180*0Sstevel@tonic-gate /* step 5 */ 181*0Sstevel@tonic-gate } 182*0Sstevel@tonic-gate 183*0Sstevel@tonic-gate if (callback != NULL) callback(2,0,cb_arg); 184*0Sstevel@tonic-gate if (callback != NULL) callback(3,0,cb_arg); 185*0Sstevel@tonic-gate 186*0Sstevel@tonic-gate /* step 6 */ 187*0Sstevel@tonic-gate counter=0; 188*0Sstevel@tonic-gate /* "offset = 2" */ 189*0Sstevel@tonic-gate 190*0Sstevel@tonic-gate n=(bits-1)/160; 191*0Sstevel@tonic-gate b=(bits-1)-n*160; 192*0Sstevel@tonic-gate 193*0Sstevel@tonic-gate for (;;) 194*0Sstevel@tonic-gate { 195*0Sstevel@tonic-gate if (callback != NULL && counter != 0) 196*0Sstevel@tonic-gate callback(0,counter,cb_arg); 197*0Sstevel@tonic-gate 198*0Sstevel@tonic-gate /* step 7 */ 199*0Sstevel@tonic-gate BN_zero(W); 200*0Sstevel@tonic-gate /* now 'buf' contains "SEED + offset - 1" */ 201*0Sstevel@tonic-gate for (k=0; k<=n; k++) 202*0Sstevel@tonic-gate { 203*0Sstevel@tonic-gate /* obtain "SEED + offset + k" by incrementing: */ 204*0Sstevel@tonic-gate for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--) 205*0Sstevel@tonic-gate { 206*0Sstevel@tonic-gate buf[i]++; 207*0Sstevel@tonic-gate if (buf[i] != 0) break; 208*0Sstevel@tonic-gate } 209*0Sstevel@tonic-gate 210*0Sstevel@tonic-gate EVP_Digest(buf,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL); 211*0Sstevel@tonic-gate 212*0Sstevel@tonic-gate /* step 8 */ 213*0Sstevel@tonic-gate if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0)) 214*0Sstevel@tonic-gate goto err; 215*0Sstevel@tonic-gate BN_lshift(r0,r0,160*k); 216*0Sstevel@tonic-gate BN_add(W,W,r0); 217*0Sstevel@tonic-gate } 218*0Sstevel@tonic-gate 219*0Sstevel@tonic-gate /* more of step 8 */ 220*0Sstevel@tonic-gate BN_mask_bits(W,bits-1); 221*0Sstevel@tonic-gate BN_copy(X,W); /* this should be ok */ 222*0Sstevel@tonic-gate BN_add(X,X,test); /* this should be ok */ 223*0Sstevel@tonic-gate 224*0Sstevel@tonic-gate /* step 9 */ 225*0Sstevel@tonic-gate BN_lshift1(r0,q); 226*0Sstevel@tonic-gate BN_mod(c,X,r0,ctx); 227*0Sstevel@tonic-gate BN_sub(r0,c,BN_value_one()); 228*0Sstevel@tonic-gate BN_sub(p,X,r0); 229*0Sstevel@tonic-gate 230*0Sstevel@tonic-gate /* step 10 */ 231*0Sstevel@tonic-gate if (BN_cmp(p,test) >= 0) 232*0Sstevel@tonic-gate { 233*0Sstevel@tonic-gate /* step 11 */ 234*0Sstevel@tonic-gate r = BN_is_prime_fasttest(p, DSS_prime_checks, callback, ctx3, cb_arg, 1); 235*0Sstevel@tonic-gate if (r > 0) 236*0Sstevel@tonic-gate goto end; /* found it */ 237*0Sstevel@tonic-gate if (r != 0) 238*0Sstevel@tonic-gate goto err; 239*0Sstevel@tonic-gate } 240*0Sstevel@tonic-gate 241*0Sstevel@tonic-gate /* step 13 */ 242*0Sstevel@tonic-gate counter++; 243*0Sstevel@tonic-gate /* "offset = offset + n + 1" */ 244*0Sstevel@tonic-gate 245*0Sstevel@tonic-gate /* step 14 */ 246*0Sstevel@tonic-gate if (counter >= 4096) break; 247*0Sstevel@tonic-gate } 248*0Sstevel@tonic-gate } 249*0Sstevel@tonic-gate end: 250*0Sstevel@tonic-gate if (callback != NULL) callback(2,1,cb_arg); 251*0Sstevel@tonic-gate 252*0Sstevel@tonic-gate /* We now need to generate g */ 253*0Sstevel@tonic-gate /* Set r0=(p-1)/q */ 254*0Sstevel@tonic-gate BN_sub(test,p,BN_value_one()); 255*0Sstevel@tonic-gate BN_div(r0,NULL,test,q,ctx); 256*0Sstevel@tonic-gate 257*0Sstevel@tonic-gate BN_set_word(test,h); 258*0Sstevel@tonic-gate BN_MONT_CTX_set(mont,p,ctx); 259*0Sstevel@tonic-gate 260*0Sstevel@tonic-gate for (;;) 261*0Sstevel@tonic-gate { 262*0Sstevel@tonic-gate /* g=test^r0%p */ 263*0Sstevel@tonic-gate BN_mod_exp_mont(g,test,r0,p,ctx,mont); 264*0Sstevel@tonic-gate if (!BN_is_one(g)) break; 265*0Sstevel@tonic-gate BN_add(test,test,BN_value_one()); 266*0Sstevel@tonic-gate h++; 267*0Sstevel@tonic-gate } 268*0Sstevel@tonic-gate 269*0Sstevel@tonic-gate if (callback != NULL) callback(3,1,cb_arg); 270*0Sstevel@tonic-gate 271*0Sstevel@tonic-gate ok=1; 272*0Sstevel@tonic-gate err: 273*0Sstevel@tonic-gate if (!ok) 274*0Sstevel@tonic-gate { 275*0Sstevel@tonic-gate if (ret != NULL) DSA_free(ret); 276*0Sstevel@tonic-gate } 277*0Sstevel@tonic-gate else 278*0Sstevel@tonic-gate { 279*0Sstevel@tonic-gate ret->p=BN_dup(p); 280*0Sstevel@tonic-gate ret->q=BN_dup(q); 281*0Sstevel@tonic-gate ret->g=BN_dup(g); 282*0Sstevel@tonic-gate if ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20); 283*0Sstevel@tonic-gate if (counter_ret != NULL) *counter_ret=counter; 284*0Sstevel@tonic-gate if (h_ret != NULL) *h_ret=h; 285*0Sstevel@tonic-gate } 286*0Sstevel@tonic-gate if (ctx != NULL) BN_CTX_free(ctx); 287*0Sstevel@tonic-gate if (ctx2 != NULL) 288*0Sstevel@tonic-gate { 289*0Sstevel@tonic-gate BN_CTX_end(ctx2); 290*0Sstevel@tonic-gate BN_CTX_free(ctx2); 291*0Sstevel@tonic-gate } 292*0Sstevel@tonic-gate if (ctx3 != NULL) BN_CTX_free(ctx3); 293*0Sstevel@tonic-gate if (mont != NULL) BN_MONT_CTX_free(mont); 294*0Sstevel@tonic-gate return(ok?ret:NULL); 295*0Sstevel@tonic-gate } 296*0Sstevel@tonic-gate #endif 297