Make DSA_generate_parameters, and fix a couple of bug

[oweals/openssl.git] / crypto / bn / bn_prime.c

diff --git a/crypto/bn/bn_prime.c b/crypto/bn/bn_prime.c
index f82cc1f605fcb692377026cdb06ffe1254469711..e679c7c8224991b97fd50e36072af8707c9bbdc3 100644 (file)
--- a/crypto/bn/bn_prime.c
+++ b/crypto/bn/bn_prime.c
@@ -68,24 +68,6 @@
  */
 #include "bn_prime.h"
 
-/* number of Miller-Rabin iterations for an error rate  of less than 2^-80
- * for random 'b'-bit input, b >= 100 (taken from table 4.4 in the Handbook
- * of Applied Cryptography [Menezes, van Oorschot, Vanstone; CRC Press 1996];
- * original paper: Damgaard, Landrock, Pomerance: Average case error estimates
- * for the strong probable prime test. -- Math. Comp. 61 (1993) 177-194) */
-#define BN_prime_checks_size(b) ((b) >= 1300 ?  2 : \
-                                (b) >=  850 ?  3 : \
-                                (b) >=  650 ?  4 : \
-                                (b) >=  550 ?  5 : \
-                                (b) >=  450 ?  6 : \
-                                (b) >=  400 ?  7 : \
-                                (b) >=  350 ?  8 : \
-                                (b) >=  300 ?  9 : \
-                                (b) >=  250 ? 12 : \
-                                (b) >=  200 ? 15 : \
-                                (b) >=  150 ? 18 : \
-                                /* b >= 100 */ 27)
-
 static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx,BN_CTX *ctx2,
        BN_MONT_CTX *mont);
 static int probable_prime(BIGNUM *rnd, int bits);
@@ -102,7 +84,7 @@ BIGNUM *BN_generate_prime(BIGNUM *ret, int bits, int safe, BIGNUM *add,
        int found=0;
        int i,j,c1=0;
        BN_CTX *ctx;
-       int checks = BN_prime_checks_size(bits);
+       int checks = BN_prime_checks_for_size(bits);
 
        ctx=BN_CTX_new();
        if (ctx == NULL) goto err;
@@ -172,10 +154,12 @@ err:
        return(found ? rnd : NULL);
        }
 
-int BN_is_prime(BIGNUM *a, int checks, void (*callback)(int,int,void *),
-            BN_CTX *ctx_passed, void *cb_arg)
+int BN_is_prime_fasttest(BIGNUM *a, int checks,
+               void (*callback)(int,int,void *),
+               BN_CTX *ctx_passed, BN_CTX *ctx2_passed, void *cb_arg,
+               int do_trial_division)
        {
-       int i,j,c2=0,ret= -1;
+       int i,j,ret= -1;
        BIGNUM *check;
        BN_CTX *ctx=NULL,*ctx2=NULL;
        BN_MONT_CTX *mont=NULL;
@@ -183,17 +167,25 @@ int BN_is_prime(BIGNUM *a, int checks, void (*callback)(int,int,void *),
        if (checks == BN_prime_checks)
                {
                int bits = BN_num_bits(a);
-               checks = BN_prime_checks_size(bits);
+               checks = BN_prime_checks_for_size(bits);
                }
 
        if (!BN_is_odd(a))
                return(0);
+       if (do_trial_division)
+               for (i = 1; i < NUMPRIMES; i++)
+                       if (BN_mod_word(a, primes[i]) == 0) 
+                               return 0;
+
        if (ctx_passed != NULL)
                ctx=ctx_passed;
        else
                if ((ctx=BN_CTX_new()) == NULL) goto err;
+       if (ctx2_passed != NULL)
+               ctx2=ctx2_passed;
+       else
+               if ((ctx2=BN_CTX_new()) == NULL) goto err;
 
-       if ((ctx2=BN_CTX_new()) == NULL) goto err;
        if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
 
        check= &(ctx->bn[ctx->tos++]);
@@ -203,7 +195,9 @@ int BN_is_prime(BIGNUM *a, int checks, void (*callback)(int,int,void *),
 
        for (i=0; i<checks; i++)
                {
-               if (!BN_rand(check,BN_num_bits(a)-1,0,0)) goto err;
+               if (!BN_pseudo_rand(check,BN_num_bits(a),0,0)) goto err;
+               if (BN_cmp(check, a) >= 0)
+                       BN_sub(check, check, a);
                j=witness(check,a,ctx,ctx2,mont);
                if (j == -1) goto err;
                if (j)
@@ -211,21 +205,25 @@ int BN_is_prime(BIGNUM *a, int checks, void (*callback)(int,int,void *),
                        ret=0;
                        goto err;
                        }
-               if (callback != NULL) callback(1,c2++,cb_arg);
+               if (callback != NULL) callback(1,i,cb_arg);
                }
        ret=1;
 err:
        ctx->tos--;
        if ((ctx_passed == NULL) && (ctx != NULL))
                BN_CTX_free(ctx);
-       if (ctx2 != NULL)
+       if ((ctx2_passed == NULL) && (ctx2 != NULL))
                BN_CTX_free(ctx2);
        if (mont != NULL) BN_MONT_CTX_free(mont);
                
        return(ret);
        }
 
-#define RECP_MUL_MOD
+int BN_is_prime(BIGNUM *a, int checks, void (*callback)(int,int,void *),
+       BN_CTX *ctx_passed, void *cb_arg)
+       {
+       return BN_is_prime_fasttest(a, checks, callback, ctx_passed, NULL, cb_arg, 0);
+       }
 
 static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx, BN_CTX *ctx2,
             BN_MONT_CTX *mont)
@@ -294,7 +292,7 @@ err:
 static int probable_prime(BIGNUM *rnd, int bits)
        {
        int i;
-       MS_STATIC BN_ULONG mods[NUMPRIMES];
+       BN_ULONG mods[NUMPRIMES];
        BN_ULONG delta,d;
 
 again:
@@ -408,18 +406,22 @@ err:
        }
 
 #if 0
-static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx)
+
+#define RECP_MUL_MOD
+
+static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx,
+                  BN_CTX *unused, BN_MONT_CTX *unused2)
        {
-       int k,i,nb,ret= -1;
+       int k,i,ret= -1;
        BIGNUM *d,*dd,*tmp;
-       BIGNUM *d1,*d2,*x,*n1,*inv;
+       BIGNUM *d1,*d2,*x,*n1;
+       BN_RECP_CTX recp;
 
        d1= &(ctx->bn[ctx->tos]);
        d2= &(ctx->bn[ctx->tos+1]);
        x=  &(ctx->bn[ctx->tos+2]);
        n1= &(ctx->bn[ctx->tos+3]);
-       inv=&(ctx->bn[ctx->tos+4]);
-       ctx->tos+=5;
+       ctx->tos+=4;
 
        d=d1;
        dd=d2;
@@ -429,8 +431,8 @@ static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx)
 
        /* i=BN_num_bits(n); */
 #ifdef RECP_MUL_MOD
-       nb=BN_reciprocal(inv,n,ctx); /**/
-       if (nb == -1) goto err;
+       BN_RECP_CTX_init(&recp);
+       if (BN_RECP_CTX_set(&recp,n,ctx) <= 0) goto err;
 #endif
 
        for (i=k-1; i>=0; i--)
@@ -439,7 +441,7 @@ static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx)
 #ifndef RECP_MUL_MOD
                if (!BN_mod_mul(dd,d,d,n,ctx)) goto err;
 #else
-               if (!BN_mod_mul_reciprocal(dd,d,d,n,inv,nb,ctx)) goto err;
+               if (!BN_mod_mul_reciprocal(dd,d,d,&recp,ctx)) goto err;
 #endif
                if (    BN_is_one(dd) &&
                        !BN_is_one(x) &&
@@ -453,7 +455,7 @@ static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx)
 #ifndef RECP_MUL_MOD
                        if (!BN_mod_mul(d,dd,a,n,ctx)) goto err;
 #else
-                       if (!BN_mod_mul_reciprocal(d,dd,a,n,inv,nb,ctx)) goto err; 
+                       if (!BN_mod_mul_reciprocal(d,dd,a,&recp,ctx)) goto err; 
 #endif
                        }
                else
@@ -468,7 +470,10 @@ static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx)
        else    i=1;
        ret=i;
 err:
-       ctx->tos-=5;
+       ctx->tos-=4;
+#ifdef RECP_MUL_MOD
+       BN_RECP_CTX_free(&recp);
+#endif
        return(ret);
        }
 #endif