/* crypto/bn/bn_prime.c */
-/* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com)
+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
#include <time.h>
#include "cryptlib.h"
#include "bn_lcl.h"
-#include "rand.h"
+#include <openssl/rand.h>
-/* The quick seive algorithm approach to weeding out primes is
+/* The quick sieve algorithm approach to weeding out primes is
* Philip Zimmermann's, as implemented in PGP. I have had a read of
* his comments and implemented my own version.
*/
#include "bn_prime.h"
-#ifndef NOPROTO
-static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx);
+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);
static int probable_prime_dh(BIGNUM *rnd, int bits,
BIGNUM *add, BIGNUM *rem, BN_CTX *ctx);
-static int probable_prime_dh_strong(BIGNUM *rnd, int bits,
+static int probable_prime_dh_safe(BIGNUM *rnd, int bits,
BIGNUM *add, BIGNUM *rem, BN_CTX *ctx);
-#else
-static int witness();
-static int probable_prime();
-static int probable_prime_dh();
-static int probable_prime_dh_strong();
-#endif
-BIGNUM *BN_generate_prime(bits,strong,add,rem,callback)
-int bits;
-int strong;
-BIGNUM *add;
-BIGNUM *rem;
-void (*callback)(P_I_I);
+BIGNUM *BN_generate_prime(BIGNUM *ret, int bits, int safe, BIGNUM *add,
+ BIGNUM *rem, void (*callback)(int,int,void *), void *cb_arg)
{
BIGNUM *rnd=NULL;
- BIGNUM *ret=NULL;
- BIGNUM *t=NULL;
+ BIGNUM t;
+ int found=0;
int i,j,c1=0;
BN_CTX *ctx;
+ int checks = BN_prime_checks_for_size(bits);
ctx=BN_CTX_new();
if (ctx == NULL) goto err;
- if ((rnd=BN_new()) == NULL) goto err;
- if (strong)
- if ((t=BN_new()) == NULL) goto err;
+ if (ret == NULL)
+ {
+ if ((rnd=BN_new()) == NULL) goto err;
+ }
+ else
+ rnd=ret;
+ BN_init(&t);
loop:
/* make a random number and set the top and bottom bits */
if (add == NULL)
}
else
{
- if (strong)
+ if (safe)
{
- if (!probable_prime_dh_strong(rnd,bits,add,rem,ctx))
+ if (!probable_prime_dh_safe(rnd,bits,add,rem,ctx))
goto err;
}
else
}
}
/* if (BN_mod_word(rnd,(BN_ULONG)3) == 1) goto loop; */
- if (callback != NULL) callback(0,c1++);
+ if (callback != NULL) callback(0,c1++,cb_arg);
- if (!strong)
+ if (!safe)
{
- i=BN_is_prime(rnd,BN_prime_checks,callback,ctx);
+ i=BN_is_prime(rnd,checks,callback,ctx,cb_arg);
if (i == -1) goto err;
if (i == 0) goto loop;
}
else
{
- /* for a strong prime generation,
+ /* for "safe prime" generation,
* check that (p-1)/2 is prime.
* Since a prime is odd, We just
* need to divide by 2 */
- if (!BN_rshift1(t,rnd)) goto err;
+ if (!BN_rshift1(&t,rnd)) goto err;
- for (i=0; i<BN_prime_checks; i++)
+ for (i=0; i<checks; i++)
{
- j=BN_is_prime(rnd,1,callback,ctx);
+ j=BN_is_prime(rnd,1,callback,ctx,cb_arg);
if (j == -1) goto err;
if (j == 0) goto loop;
- j=BN_is_prime(t,1,callback,ctx);
+ j=BN_is_prime(&t,1,callback,ctx,cb_arg);
if (j == -1) goto err;
if (j == 0) goto loop;
- if (callback != NULL) callback(2,c1-1);
- /* We have a strong prime test pass */
+ if (callback != NULL) callback(2,c1-1,cb_arg);
+ /* We have a safe prime test pass */
}
}
/* we have a prime :-) */
- ret=rnd;
+ found = 1;
err:
- if ((ret == NULL) && (rnd != NULL)) BN_free(rnd);
- if (t != NULL) BN_free(t);
+ if (!found && (ret == NULL) && (rnd != NULL)) BN_free(rnd);
+ BN_free(&t);
if (ctx != NULL) BN_CTX_free(ctx);
- return(ret);
+ return(found ? rnd : NULL);
}
-int BN_is_prime(a,checks,callback,ctx_passed)
-BIGNUM *a;
-int checks;
-void (*callback)(P_I_I);
-BN_CTX *ctx_passed;
+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;
+ BN_CTX *ctx=NULL,*ctx2=NULL;
+ BN_MONT_CTX *mont=NULL;
+
+ if (checks == BN_prime_checks)
+ {
+ int bits = BN_num_bits(a);
+ 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 (callback != NULL) callback(1,-1,cb_arg);
+ }
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 ((mont=BN_MONT_CTX_new()) == NULL) goto err;
+
+ check= &(ctx->bn[ctx->tos++]);
+
+ /* Setup the montgomery structure */
+ if (!BN_MONT_CTX_set(mont,a,ctx2)) goto err;
- check=ctx->bn[ctx->tos++];
for (i=0; i<checks; i++)
{
- if (!BN_rand(check,BN_num_bits(a)-1,0,0)) goto err;
- j=witness(check,a,ctx);
+ 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)
{
ret=0;
goto err;
}
- if (callback != NULL) callback(1,c2++);
+ 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_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(a, n,ctx)
-BIGNUM *a;
-BIGNUM *n;
-BN_CTX *ctx;
+static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx, BN_CTX *ctx2,
+ BN_MONT_CTX *mont)
{
- int k,i,nb,ret= -1;
- BIGNUM *d,*dd,*tmp;
- BIGNUM *d1,*d2,*x,*n1,*inv;
+ int k,i,ret= -1,good;
+ BIGNUM *d,*dd,*tmp,*d1,*d2,*n1;
+ BIGNUM *mont_one,*mont_n1,*mont_a;
+
+ d1= &(ctx->bn[ctx->tos]);
+ d2= &(ctx->bn[ctx->tos+1]);
+ n1= &(ctx->bn[ctx->tos+2]);
+ ctx->tos+=3;
- 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;
+ mont_one= &(ctx2->bn[ctx2->tos]);
+ mont_n1= &(ctx2->bn[ctx2->tos+1]);
+ mont_a= &(ctx2->bn[ctx2->tos+2]);
+ ctx2->tos+=3;
d=d1;
dd=d2;
if (!BN_sub(n1,n,d)) goto err; /* n1=n-1; */
k=BN_num_bits(n1);
- /* i=BN_num_bits(n); */
-#ifdef RECP_MUL_MOD
- nb=BN_reciprocal(inv,n,ctx); /**/
- if (nb == -1) goto err;
-#endif
+ if (!BN_to_montgomery(mont_one,BN_value_one(),mont,ctx2)) goto err;
+ if (!BN_to_montgomery(mont_n1,n1,mont,ctx2)) goto err;
+ if (!BN_to_montgomery(mont_a,a,mont,ctx2)) goto err;
+ BN_copy(d,mont_one);
for (i=k-1; i>=0; i--)
{
- if (BN_copy(x,d) == NULL) goto err;
-#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;
-#endif
- if ( BN_is_one(dd) &&
- !BN_is_one(x) &&
- (BN_cmp(x,n1) != 0))
+ if ( (BN_cmp(d,mont_one) != 0) &&
+ (BN_cmp(d,mont_n1) != 0))
+ good=1;
+ else
+ good=0;
+
+ BN_mod_mul_montgomery(dd,d,d,mont,ctx2);
+
+ if (good && (BN_cmp(dd,mont_one) == 0))
{
ret=1;
goto err;
}
if (BN_is_bit_set(n1,i))
{
-#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;
-#endif
+ BN_mod_mul_montgomery(d,dd,mont_a,mont,ctx2);
}
else
{
dd=tmp;
}
}
- if (BN_is_one(d))
+ if (BN_cmp(d,mont_one) == 0)
i=0;
else i=1;
ret=i;
err:
- ctx->tos-=5;
+ ctx->tos-=3;
+ ctx2->tos-=3;
return(ret);
}
-static int probable_prime(rnd, bits)
-BIGNUM *rnd;
-int bits;
+static int probable_prime(BIGNUM *rnd, int bits)
{
int i;
- MS_STATIC BN_ULONG mods[NUMPRIMES];
- BN_ULONG delta;
+ BN_ULONG mods[NUMPRIMES];
+ BN_ULONG delta,d;
+again:
if (!BN_rand(rnd,bits,1,1)) return(0);
/* we now have a random number 'rand' to test. */
for (i=1; i<NUMPRIMES; i++)
* that gcd(rnd-1,primes) == 1 (except for 2) */
if (((mods[i]+delta)%primes[i]) <= 1)
{
+ d=delta;
delta+=2;
/* perhaps need to check for overflow of
- * delta (but delta can be upto 2^32) */
+ * delta (but delta can be upto 2^32)
+ * 21-May-98 eay - added overflow check */
+ if (delta < d) goto again;
goto loop;
}
}
return(1);
}
-static int probable_prime_dh(rnd, bits, add, rem,ctx)
-BIGNUM *rnd;
-int bits;
-BIGNUM *add;
-BIGNUM *rem;
-BN_CTX *ctx;
+static int probable_prime_dh(BIGNUM *rnd, int bits, BIGNUM *add, BIGNUM *rem,
+ BN_CTX *ctx)
{
int i,ret=0;
BIGNUM *t1;
- t1=ctx->bn[ctx->tos++];
+ t1= &(ctx->bn[ctx->tos++]);
if (!BN_rand(rnd,bits,0,1)) goto err;
loop: for (i=1; i<NUMPRIMES; i++)
{
/* check that rnd is a prime */
- if (BN_mod_word(rnd,(BN_LONG)primes[i]) <= 1)
+ if (BN_mod_word(rnd,(BN_ULONG)primes[i]) <= 1)
{
if (!BN_add(rnd,rnd,add)) goto err;
goto loop;
return(ret);
}
-static int probable_prime_dh_strong(p, bits, padd, rem,ctx)
-BIGNUM *p;
-int bits;
-BIGNUM *padd;
-BIGNUM *rem;
-BN_CTX *ctx;
+static int probable_prime_dh_safe(BIGNUM *p, int bits, BIGNUM *padd,
+ BIGNUM *rem, BN_CTX *ctx)
{
int i,ret=0;
BIGNUM *t1,*qadd=NULL,*q=NULL;
bits--;
- t1=ctx->bn[ctx->tos++];
- q=ctx->bn[ctx->tos++];
- qadd=ctx->bn[ctx->tos++];
+ t1= &(ctx->bn[ctx->tos++]);
+ q= &(ctx->bn[ctx->tos++]);
+ qadd= &(ctx->bn[ctx->tos++]);
if (!BN_rshift1(qadd,padd)) goto err;
/* check that p and q are prime */
/* check that for p and q
* gcd(p-1,primes) == 1 (except for 2) */
- if ( (BN_mod_word(p,(BN_LONG)primes[i]) == 0) ||
- (BN_mod_word(q,(BN_LONG)primes[i]) == 0))
+ if ( (BN_mod_word(p,(BN_ULONG)primes[i]) == 0) ||
+ (BN_mod_word(q,(BN_ULONG)primes[i]) == 0))
{
if (!BN_add(p,p,padd)) goto err;
if (!BN_add(q,q,qadd)) goto err;
return(ret);
}
+#if 0
+
+#define RECP_MUL_MOD
+
+static int witness(BIGNUM *a, BIGNUM *n, BN_CTX *ctx,
+ BN_CTX *unused, BN_MONT_CTX *unused2)
+ {
+ int k,i,ret= -1;
+ BIGNUM *d,*dd,*tmp;
+ 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]);
+ ctx->tos+=4;
+
+ d=d1;
+ dd=d2;
+ if (!BN_one(d)) goto err;
+ if (!BN_sub(n1,n,d)) goto err; /* n1=n-1; */
+ k=BN_num_bits(n1);
+
+ /* i=BN_num_bits(n); */
+#ifdef RECP_MUL_MOD
+ BN_RECP_CTX_init(&recp);
+ if (BN_RECP_CTX_set(&recp,n,ctx) <= 0) goto err;
+#endif
+
+ for (i=k-1; i>=0; i--)
+ {
+ if (BN_copy(x,d) == NULL) goto err;
+#ifndef RECP_MUL_MOD
+ if (!BN_mod_mul(dd,d,d,n,ctx)) goto err;
+#else
+ if (!BN_mod_mul_reciprocal(dd,d,d,&recp,ctx)) goto err;
+#endif
+ if ( BN_is_one(dd) &&
+ !BN_is_one(x) &&
+ (BN_cmp(x,n1) != 0))
+ {
+ ret=1;
+ goto err;
+ }
+ if (BN_is_bit_set(n1,i))
+ {
+#ifndef RECP_MUL_MOD
+ if (!BN_mod_mul(d,dd,a,n,ctx)) goto err;
+#else
+ if (!BN_mod_mul_reciprocal(d,dd,a,&recp,ctx)) goto err;
+#endif
+ }
+ else
+ {
+ tmp=d;
+ d=dd;
+ dd=tmp;
+ }
+ }
+ if (BN_is_one(d))
+ i=0;
+ else i=1;
+ ret=i;
+err:
+ ctx->tos-=4;
+#ifdef RECP_MUL_MOD
+ BN_RECP_CTX_free(&recp);
+#endif
+ return(ret);
+ }
+#endif
projects / openssl.git / blobdiff