diff options
author | Ralf S. Engelschall <rse@openssl.org> | 1998-12-21 10:52:47 +0000 |
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committer | Ralf S. Engelschall <rse@openssl.org> | 1998-12-21 10:52:47 +0000 |
commit | d02b48c63a58ea4367a0e905979f140b7d090f86 (patch) | |
tree | 504f62ed3d84799f785b9cd9fab255a21b0e1b0e /crypto/dsa/dsa_gen.c |
Import of old SSLeay release: SSLeay 0.8.1b
Diffstat (limited to 'crypto/dsa/dsa_gen.c')
-rw-r--r-- | crypto/dsa/dsa_gen.c | 325 |
1 files changed, 325 insertions, 0 deletions
diff --git a/crypto/dsa/dsa_gen.c b/crypto/dsa/dsa_gen.c new file mode 100644 index 0000000000..2b80104e7b --- /dev/null +++ b/crypto/dsa/dsa_gen.c @@ -0,0 +1,325 @@ +/* crypto/dsa/dsa_gen.c */ +/* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com) + * All rights reserved. + * + * This package is an SSL implementation written + * by Eric Young (eay@cryptsoft.com). + * The implementation was written so as to conform with Netscapes SSL. + * + * This library is free for commercial and non-commercial use as long as + * the following conditions are aheared to. The following conditions + * apply to all code found in this distribution, be it the RC4, RSA, + * lhash, DES, etc., code; not just the SSL code. The SSL documentation + * included with this distribution is covered by the same copyright terms + * except that the holder is Tim Hudson (tjh@cryptsoft.com). + * + * Copyright remains Eric Young's, and as such any Copyright notices in + * the code are not to be removed. + * If this package is used in a product, Eric Young should be given attribution + * as the author of the parts of the library used. + * This can be in the form of a textual message at program startup or + * in documentation (online or textual) provided with the package. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * "This product includes cryptographic software written by + * Eric Young (eay@cryptsoft.com)" + * The word 'cryptographic' can be left out if the rouines from the library + * being used are not cryptographic related :-). + * 4. If you include any Windows specific code (or a derivative thereof) from + * the apps directory (application code) you must include an acknowledgement: + * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" + * + * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * The licence and distribution terms for any publically available version or + * derivative of this code cannot be changed. i.e. this code cannot simply be + * copied and put under another distribution licence + * [including the GNU Public Licence.] + */ + +#undef GENUINE_DSA + +#ifdef GENUINE_DSA +#define HASH SHA +#else +#define HASH SHA1 +#endif + +#include <stdio.h> +#include <time.h> +#include "cryptlib.h" +#include "sha.h" +#include "bn.h" +#include "dsa.h" +#include "rand.h" + +DSA *DSA_generate_parameters(bits,seed_in,seed_len,counter_ret,h_ret,callback) +int bits; +unsigned char *seed_in; +int seed_len; +int *counter_ret; +unsigned long *h_ret; +void (*callback)(); + { + int ok=0; + unsigned char seed[SHA_DIGEST_LENGTH]; + unsigned char md[SHA_DIGEST_LENGTH]; + unsigned char buf[SHA_DIGEST_LENGTH],buf2[SHA_DIGEST_LENGTH]; + BIGNUM *r0,*W,*X,*c,*test; + BIGNUM *g=NULL,*q=NULL,*p=NULL; + int k,n=0,i,b,m=0; + int counter=0; + BN_CTX *ctx=NULL,*ctx2=NULL; + unsigned int h=2; + DSA *ret=NULL; + + if (bits < 512) bits=512; + bits=(bits+63)/64*64; + + if ((seed_in != NULL) && (seed_len == 20)) + memcpy(seed,seed_in,seed_len); + + ctx=BN_CTX_new(); + if (ctx == NULL) goto err; + ctx2=BN_CTX_new(); + if (ctx2 == NULL) goto err; + ret=DSA_new(); + if (ret == NULL) goto err; + r0=ctx2->bn[0]; + g=ctx2->bn[1]; + W=ctx2->bn[2]; + q=ctx2->bn[3]; + X=ctx2->bn[4]; + c=ctx2->bn[5]; + p=ctx2->bn[6]; + test=ctx2->bn[7]; + + BN_lshift(test,BN_value_one(),bits-1); + + for (;;) + { + for (;;) + { + /* step 1 */ + if (callback != NULL) callback(0,m++); + + if (!seed_len) + RAND_bytes(seed,SHA_DIGEST_LENGTH); + else + seed_len=0; + + memcpy(buf,seed,SHA_DIGEST_LENGTH); + memcpy(buf2,seed,SHA_DIGEST_LENGTH); + for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--) + { + buf[i]++; + if (buf[i] != 0) break; + } + + /* step 2 */ + HASH(seed,SHA_DIGEST_LENGTH,md); + HASH(buf,SHA_DIGEST_LENGTH,buf2); + for (i=0; i<SHA_DIGEST_LENGTH; i++) + md[i]^=buf2[i]; + + /* step 3 */ + md[0]|=0x80; + md[SHA_DIGEST_LENGTH-1]|=0x01; + if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) abort(); + + /* step 4 */ + if (DSA_is_prime(q,callback) > 0) break; + /* do a callback call */ + /* step 5 */ + } + + if (callback != NULL) callback(2,0); + if (callback != NULL) callback(3,0); + + /* step 6 */ + counter=0; + + n=(bits-1)/160; + b=(bits-1)-n*160; + + for (;;) + { + /* step 7 */ + BN_zero(W); + for (k=0; k<=n; k++) + { + for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--) + { + buf[i]++; + if (buf[i] != 0) break; + } + + HASH(buf,SHA_DIGEST_LENGTH,md); + + /* step 8 */ + if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0)) abort(); + BN_lshift(r0,r0,160*k); + BN_add(W,W,r0); + } + + /* more of step 8 */ + BN_mask_bits(W,bits-1); + BN_copy(X,W); /* this should be ok */ + BN_add(X,X,test); /* this should be ok */ + + /* step 9 */ + BN_lshift1(r0,q); + BN_mod(c,X,r0,ctx); + BN_sub(r0,c,BN_value_one()); + BN_sub(p,X,r0); + + /* step 10 */ + if (BN_cmp(p,test) >= 0) + { + /* step 11 */ + if (DSA_is_prime(p,callback) > 0) + goto end; + } + + /* step 13 */ + counter++; + + /* step 14 */ + if (counter >= 4096) break; + + if (callback != NULL) callback(0,counter); + } + } +end: + if (callback != NULL) callback(2,1); + + /* We now need to gernerate g */ + /* Set r0=(p-1)/q */ + BN_sub(test,p,BN_value_one()); + BN_div(r0,NULL,test,q,ctx); + + BN_set_word(test,h); + for (;;) + { + /* g=test^r0%p */ + BN_mod_exp(g,test,r0,p,ctx); + if (!BN_is_one(g)) break; + BN_add(test,test,BN_value_one()); + h++; + } + + if (callback != NULL) callback(3,1); + + ok=1; +err: + if (!ok) + { + if (ret != NULL) DSA_free(ret); + } + else + { + ret->p=BN_dup(p); + ret->q=BN_dup(q); + ret->g=BN_dup(g); + if ((m > 1) && (seed_in != NULL)) memcpy(seed_in,seed,20); + if (counter_ret != NULL) *counter_ret=counter; + if (h_ret != NULL) *h_ret=h; + } + BN_CTX_free(ctx); + BN_CTX_free(ctx2); + return(ok?ret:NULL); + } + +int DSA_is_prime(w, callback) +BIGNUM *w; +void (*callback)(); + { + int ok= -1,j,i,n; + BN_CTX *ctx=NULL,*ctx2=NULL; + BIGNUM *w_1,*b,*m,*z; + int a; + + if (!BN_is_bit_set(w,0)) return(0); + + ctx=BN_CTX_new(); + if (ctx == NULL) goto err; + ctx2=BN_CTX_new(); + if (ctx2 == NULL) goto err; + + m= ctx2->bn[2]; + b= ctx2->bn[3]; + z= ctx2->bn[4]; + w_1=ctx2->bn[5]; + + /* step 1 */ + n=50; + + /* step 2 */ + if (!BN_sub(w_1,w,BN_value_one())) goto err; + for (a=1; !BN_is_bit_set(w_1,a); a++) + ; + if (!BN_rshift(m,w_1,a)) goto err; + + for (i=1; i < n; i++) + { + /* step 3 */ + BN_rand(b,BN_num_bits(w)-2/*-1*/,0,0); + BN_set_word(b,0x10001L); + + /* step 4 */ + j=0; + if (!BN_mod_exp(z,b,m,w,ctx)) goto err; + + /* step 5 */ + for (;;) + { + if (((j == 0) && BN_is_one(z)) || (BN_cmp(z,w_1) == 0)) + break; + + /* step 6 */ + if ((j > 0) && BN_is_one(z)) + { + ok=0; + goto err; + } + + j++; + if (j >= a) + { + ok=0; + goto err; + } + + if (!BN_mod_mul(z,z,z,w,ctx)) goto err; + if (callback != NULL) callback(1,j); + } + } + + ok=1; +err: + if (ok == -1) DSAerr(DSA_F_DSA_IS_PRIME,ERR_R_BN_LIB); + BN_CTX_free(ctx); + BN_CTX_free(ctx2); + + return(ok); + } + |