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Diffstat (limited to 'crypto/dsa/dsa_gen.c')
-rw-r--r--crypto/dsa/dsa_gen.c140
1 files changed, 46 insertions, 94 deletions
diff --git a/crypto/dsa/dsa_gen.c b/crypto/dsa/dsa_gen.c
index 5df9132dd8..f7e0b585a1 100644
--- a/crypto/dsa/dsa_gen.c
+++ b/crypto/dsa/dsa_gen.c
@@ -59,12 +59,18 @@
#undef GENUINE_DSA
#ifdef GENUINE_DSA
+/* Parameter generation follows the original release of FIPS PUB 186,
+ * Appendix 2.2 (i.e. use SHA as defined in FIPS PUB 180) */
#define HASH SHA
#else
+/* Parameter generation follows the updated Appendix 2.2 for FIPS PUB 186,
+ * also Appendix 2.2 of FIPS PUB 186-1 (i.e. use SHA as defined in
+ * FIPS PUB 180-1) */
#define HASH SHA1
#endif
#ifndef NO_SHA
+
#include <stdio.h>
#include <time.h>
#include "cryptlib.h"
@@ -74,8 +80,8 @@
#include <openssl/rand.h>
DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len,
- int *counter_ret, unsigned long *h_ret, void (*callback)(),
- void *cb_arg)
+ int *counter_ret, unsigned long *h_ret, void (*callback)(),
+ void *cb_arg)
{
int ok=0;
unsigned char seed[SHA_DIGEST_LENGTH];
@@ -86,19 +92,26 @@ DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len,
BN_MONT_CTX *mont=NULL;
int k,n=0,i,b,m=0;
int counter=0;
- BN_CTX *ctx=NULL,*ctx2=NULL;
+ int r=0;
+ BN_CTX *ctx=NULL,*ctx2=NULL,*ctx3=NULL,*ctx4=NULL;
unsigned int h=2;
DSA *ret=NULL;
if (bits < 512) bits=512;
bits=(bits+63)/64*64;
- if (seed_len < 20) seed_in = NULL;
+ if (seed_len < 20)
+ seed_in = NULL; /* seed buffer too small -- ignore */
+ if (seed_len > 20)
+ seed_len = 20; /* App. 2.2 of FIPS PUB 186 allows larger SEED,
+ * but our internal buffers are restricted to 160 bits*/
if ((seed_in != NULL) && (seed_len == 20))
memcpy(seed,seed_in,seed_len);
if ((ctx=BN_CTX_new()) == NULL) goto err;
if ((ctx2=BN_CTX_new()) == NULL) goto err;
+ if ((ctx3=BN_CTX_new()) == NULL) goto err;
+ if ((ctx4=BN_CTX_new()) == NULL) goto err;
if ((ret=DSA_new()) == NULL) goto err;
if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
@@ -116,18 +129,24 @@ DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len,
for (;;)
{
- for (;;)
+ for (;;) /* find q */
{
+ int seed_is_random = 0;
+
/* step 1 */
if (callback != NULL) callback(0,m++,cb_arg);
if (!seed_len)
+ {
RAND_pseudo_bytes(seed,SHA_DIGEST_LENGTH);
+ seed_is_random = 1;
+ }
else
+ /* use random seed if 'seed_in' turns out to be bad */
seed_len=0;
-
memcpy(buf,seed,SHA_DIGEST_LENGTH);
memcpy(buf2,seed,SHA_DIGEST_LENGTH);
+ /* precompute "SEED + 1" for step 7: */
for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--)
{
buf[i]++;
@@ -146,7 +165,12 @@ DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len,
if (!BN_bin2bn(md,SHA_DIGEST_LENGTH,q)) goto err;
/* step 4 */
- if (BN_is_prime(q,BN_prime_checks,callback,NULL,cb_arg) > 0) break;
+ r = BN_is_prime_fasttest(q, DSS_prime_checks, callback, ctx3, ctx4, cb_arg, seed_is_random);
+ if (r > 0)
+ break;
+ if (r != 0)
+ goto err;
+
/* do a callback call */
/* step 5 */
}
@@ -156,16 +180,22 @@ DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len,
/* step 6 */
counter=0;
+ /* "offset = 2" */
n=(bits-1)/160;
b=(bits-1)-n*160;
for (;;)
{
+ if (callback != NULL && counter != 0)
+ callback(0,counter,cb_arg);
+
/* step 7 */
BN_zero(W);
+ /* now 'buf' contains "SEED + offset - 1" */
for (k=0; k<=n; k++)
{
+ /* obtain "SEED + offset + k" by incrementing: */
for (i=SHA_DIGEST_LENGTH-1; i >= 0; i--)
{
buf[i]++;
@@ -196,17 +226,19 @@ DSA *DSA_generate_parameters(int bits, unsigned char *seed_in, int seed_len,
if (BN_cmp(p,test) >= 0)
{
/* step 11 */
- if (BN_is_prime(p,BN_prime_checks,callback,NULL,cb_arg) > 0)
- goto end;
+ r = BN_is_prime_fasttest(p, DSS_prime_checks, callback, ctx3, ctx4, cb_arg, 1);
+ if (r > 0)
+ goto end; /* found it */
+ if (r != 0)
+ goto err;
}
/* step 13 */
counter++;
+ /* "offset = offset + n + 1" */
/* step 14 */
if (counter >= 4096) break;
-
- if (callback != NULL) callback(0,counter,cb_arg);
}
}
end:
@@ -247,90 +279,10 @@ err:
if (h_ret != NULL) *h_ret=h;
}
if (ctx != NULL) BN_CTX_free(ctx);
- if (ctx != NULL) BN_CTX_free(ctx2);
+ if (ctx2 != NULL) BN_CTX_free(ctx2);
+ if (ctx3 != NULL) BN_CTX_free(ctx3);
+ if (ctx4 != NULL) BN_CTX_free(ctx4);
if (mont != NULL) BN_MONT_CTX_free(mont);
return(ok?ret:NULL);
}
-
-int DSA_is_prime(BIGNUM *w, void (*callback)(), void *cb_arg)
- {
- int ok= -1,j,i,n;
- BN_CTX *ctx=NULL,*ctx2=NULL;
- BIGNUM *w_1,*b,*m,*z,*tmp,*mont_1;
- int a;
- BN_MONT_CTX *mont=NULL;
-
- if (!BN_is_odd(w)) return(0);
-
- if ((ctx=BN_CTX_new()) == NULL) goto err;
- if ((ctx2=BN_CTX_new()) == NULL) goto err;
- if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
-
- m= &(ctx2->bn[2]);
- b= &(ctx2->bn[3]);
- z= &(ctx2->bn[4]);
- w_1= &(ctx2->bn[5]);
- tmp= &(ctx2->bn[6]);
- mont_1= &(ctx2->bn[7]);
-
- /* step 1 */
- n=BN_prime_checks_size(BN_num_bits(w));
-
- /* 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;
-
- BN_MONT_CTX_set(mont,w,ctx);
- BN_to_montgomery(mont_1,BN_value_one(),mont,ctx);
- BN_to_montgomery(w_1,w_1,mont,ctx);
- for (i=1; i < n; i++)
- {
- /* step 3 */
- if (!BN_pseudo_rand(b,BN_num_bits(w)-2/*-1*/,0,0))
- goto err;
- /* BN_set_word(b,0x10001L); */
-
- /* step 4 */
- j=0;
- if (!BN_mod_exp_mont(z,b,m,w,ctx,mont)) goto err;
-
- if (!BN_to_montgomery(z,z,mont,ctx)) goto err;
-
- /* step 5 */
- for (;;)
- {
- if (((j == 0) && (BN_cmp(z,mont_1) == 0)) ||
- (BN_cmp(z,w_1) == 0))
- break;
-
- /* step 6 */
- if ((j > 0) && (BN_cmp(z,mont_1) == 0))
- {
- ok=0;
- goto err;
- }
-
- j++;
- if (j >= a)
- {
- ok=0;
- goto err;
- }
-
- if (!BN_mod_mul_montgomery(z,z,z,mont,ctx)) goto err;
- if (callback != NULL) callback(1,j,cb_arg);
- }
- }
-
- ok=1;
-err:
- if (ok == -1) DSAerr(DSA_F_DSA_IS_PRIME,ERR_R_BN_LIB);
- BN_CTX_free(ctx);
- BN_CTX_free(ctx2);
- BN_MONT_CTX_free(mont);
-
- return(ok);
- }
#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-07 10:53:42 +0000