#undef GENUINE_DSA
#ifdef GENUINE_DSA
#define HASH EVP_sha()
#else
#define HASH EVP_sha1()
#endif
#include <openssl/opensslconf.h>
#ifndef OPENSSL_NO_SHA
#include <stdio.h>
#include <time.h>
#include <string.h>
#include <openssl/evp.h>
#include <openssl/bn.h>
#include <openssl/dsa.h>
#include <openssl/rand.h>
#include <openssl/sha.h>
#include <openssl/err.h>
#ifdef OPENSSL_FIPS
static int dsa_builtin_paramgen(DSA *ret, int bits,
unsigned char *seed_in, int seed_len,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb);
int DSA_generate_parameters_ex(DSA *ret, int bits,
unsigned char *seed_in, int seed_len,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
{
if(ret->meth->dsa_paramgen)
return ret->meth->dsa_paramgen(ret, bits, seed_in, seed_len,
counter_ret, h_ret, cb);
return dsa_builtin_paramgen(ret, bits, seed_in, seed_len,
counter_ret, h_ret, cb);
}
static int dsa_builtin_paramgen(DSA *ret, int bits,
unsigned char *seed_in, int seed_len,
int *counter_ret, unsigned long *h_ret, BN_GENCB *cb)
{
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;
BN_MONT_CTX *mont=NULL;
int k,n=0,i,b,m=0;
int counter=0;
int r=0;
BN_CTX *ctx=NULL;
unsigned int h=2;
if(FIPS_selftest_failed())
{
FIPSerr(FIPS_F_DSA_BUILTIN_PARAMGEN,
FIPS_R_FIPS_SELFTEST_FAILED);
goto err;
}
if (FIPS_mode() && (bits < OPENSSL_DSA_FIPS_MIN_MODULUS_BITS))
{
DSAerr(DSA_F_DSA_BUILTIN_PARAMGEN, DSA_R_KEY_SIZE_TOO_SMALL);
goto err;
}
if (bits < 512) bits=512;
bits=(bits+63)/64*64;
if (seed_len && (seed_len < 20))
seed_in = NULL;
if (seed_len > 20)
seed_len = 20;
if ((seed_in != NULL) && (seed_len == 20))
{
memcpy(seed,seed_in,seed_len);
seed_in = NULL;
}
if ((ctx=BN_CTX_new()) == NULL) goto err;
if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
BN_CTX_start(ctx);
r0 = BN_CTX_get(ctx);
g = BN_CTX_get(ctx);
W = BN_CTX_get(ctx);
q = BN_CTX_get(ctx);
X = BN_CTX_get(ctx);
c = BN_CTX_get(ctx);
p = BN_CTX_get(ctx);
test = BN_CTX_get(ctx);
if (!BN_lshift(test,BN_value_one(),bits-1))
goto err;
for (;;)
{
for (;;)
{
int seed_is_random;
if(!BN_GENCB_call(cb, 0, m++))
goto err;
if (!seed_len)
{
RAND_pseudo_bytes(seed,SHA_DIGEST_LENGTH);
seed_is_random = 1;
}
else
{
seed_is_random = 0;
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;
}
EVP_Digest(seed,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL);
EVP_Digest(buf,SHA_DIGEST_LENGTH,buf2,NULL,HASH, NULL);
for (i=0; i<SHA_DIGEST_LENGTH; i++)
md[i]^=buf2[i];
md[0]|=0x80;
md[SHA_DIGEST_LENGTH-1]|=0x01;
if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err;
r = BN_is_prime_fasttest_ex(q, DSS_prime_checks, ctx,
seed_is_random, cb);
if (r > 0)
break;
if (r != 0)
goto err;
}
if(!BN_GENCB_call(cb, 2, 0)) goto err;
if(!BN_GENCB_call(cb, 3, 0)) goto err;
counter=0;
n=(bits-1)/160;
b=(bits-1)-n*160;
for (;;)
{
if ((counter != 0) && !BN_GENCB_call(cb, 0, counter))
goto err;
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;
}
EVP_Digest(buf,SHA_DIGEST_LENGTH,md,NULL,HASH, NULL);
if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,r0))
goto err;
if (!BN_lshift(r0,r0,160*k)) goto err;
if (!BN_add(W,W,r0)) goto err;
}
if (!BN_mask_bits(W,bits-1)) goto err;
if (!BN_copy(X,W)) goto err;
if (!BN_add(X,X,test)) goto err;
if (!BN_lshift1(r0,q)) goto err;
if (!BN_mod(c,X,r0,ctx)) goto err;
if (!BN_sub(r0,c,BN_value_one())) goto err;
if (!BN_sub(p,X,r0)) goto err;
if (BN_cmp(p,test) >= 0)
{
r = BN_is_prime_fasttest_ex(p, DSS_prime_checks,
ctx, 1, cb);
if (r > 0)
goto end;
if (r != 0)
goto err;
}
counter++;
if (counter >= 4096) break;
}
}
end:
if(!BN_GENCB_call(cb, 2, 1))
goto err;
if (!BN_sub(test,p,BN_value_one())) goto err;
if (!BN_div(r0,NULL,test,q,ctx)) goto err;
if (!BN_set_word(test,h)) goto err;
if (!BN_MONT_CTX_set(mont,p,ctx)) goto err;
for (;;)
{
if (!BN_mod_exp_mont(g,test,r0,p,ctx,mont)) goto err;
if (!BN_is_one(g)) break;
if (!BN_add(test,test,BN_value_one())) goto err;
h++;
}
if(!BN_GENCB_call(cb, 3, 1))
goto err;
ok=1;
err:
if (ok)
{
if(ret->p) BN_free(ret->p);
if(ret->q) BN_free(ret->q);
if(ret->g) BN_free(ret->g);
ret->p=BN_dup(p);
ret->q=BN_dup(q);
ret->g=BN_dup(g);
if (ret->p == NULL || ret->q == NULL || ret->g == NULL)
{
ok=0;
goto err;
}
if (seed_in != NULL) memcpy(seed_in,seed,20);
if (counter_ret != NULL) *counter_ret=counter;
if (h_ret != NULL) *h_ret=h;
}
if(ctx)
{
BN_CTX_end(ctx);
BN_CTX_free(ctx);
}
if (mont != NULL) BN_MONT_CTX_free(mont);
return ok;
}
#endif
#endif