openssl/crypto/bn/test.c
1998-12-21 11:00:56 +00:00

253 lines
5.0 KiB
C

#include <stdio.h>
#include "cryptlib.h"
#include "bn_lcl.h"
#define SIZE 32
#define BN_MONT_CTX_set bn_mcs
#define BN_from_montgomery bn_fm
#define BN_mod_mul_montgomery bn_mmm
#undef BN_to_montgomery
#define BN_to_montgomery(r,a,mont,ctx) bn_mmm(\
r,a,(mont)->RR,(mont),ctx)
main()
{
BIGNUM prime,a,b,r,A,B,R;
BN_MONT_CTX *mont;
BN_CTX *ctx;
int i;
ctx=BN_CTX_new();
BN_init(&prime);
BN_init(&a); BN_init(&b); BN_init(&r);
BN_init(&A); BN_init(&B); BN_init(&R);
BN_generate_prime(&prime,SIZE,0,NULL,NULL,NULL,NULL);
BN_rand(&A,SIZE,1,0);
BN_rand(&B,SIZE,1,0);
BN_mod(&A,&A,&prime,ctx);
BN_mod(&B,&B,&prime,ctx);
i=A.top;
BN_mul(&R,&A,&B,ctx);
BN_mask_bits(&R,i*BN_BITS2);
BN_print_fp(stdout,&A); printf(" <- a\n");
BN_print_fp(stdout,&B); printf(" <- b\n");
BN_mul_high(&r,&A,&B,&R,i);
BN_print_fp(stdout,&r); printf(" <- high(BA*DC)\n");
BN_mask_bits(&A,i*32);
BN_mask_bits(&B,i*32);
BN_mul(&R,&A,&B);
BN_rshift(&R,&R,i*32);
BN_print_fp(stdout,&R); printf(" <- norm BA*DC\n");
BN_sub(&R,&R,&r);
BN_print_fp(stdout,&R); printf(" <- diff\n");
}
#if 0
int bn_mul_high(r,a,b,low,words)
BIGNUM *r,*a,*b,*low;
int words;
{
int i;
BIGNUM t1,t2,t3,h,ah,al,bh,bl,m,s0,s1;
BN_init(&al); BN_init(&ah);
BN_init(&bl); BN_init(&bh);
BN_init(&t1); BN_init(&t2); BN_init(&t3);
BN_init(&s0); BN_init(&s1);
BN_init(&h); BN_init(&m);
i=a->top;
if (i >= words)
{
al.top=words;
ah.top=a->top-words;
ah.d= &(a->d[ah.top]);
}
else
al.top=i;
al.d=a->d;
i=b->top;
if (i >= words)
{
bl.top=words;
bh.top=i-words;
bh.d= &(b->d[bh.top]);
}
else
bl.top=i;
bl.d=b->d;
i=low->top;
if (i >= words)
{
s0.top=words;
s1.top=i-words;
s1.d= &(low->d[s1.top]);
}
else
s0.top=i;
s0.d=low->d;
al.max=al.top; ah.max=ah.top;
bl.max=bl.top; bh.max=bh.top;
s0.max=bl.top; s1.max=bh.top;
/* Calculate (al-ah)*(bh-bl) */
BN_sub(&t1,&al,&ah);
BN_sub(&t2,&bh,&bl);
BN_mul(&m,&t1,&t2);
/* Calculate ah*bh */
BN_mul(&h,&ah,&bh);
/* s0 == low(al*bl)
* s1 == low(ah*bh)+low((al-ah)*(bh-bl))+low(al*bl)+high(al*bl)
* We know s0 and s1 so the only unknown is high(al*bl)
* high(al*bl) == s1 - low(ah*bh+(al-ah)*(bh-bl)+s0)
*/
BN_add(&m,&m,&h);
BN_add(&t2,&m,&s0);
/* Quick and dirty mask off of high words */
t3.d=t2.d;
t3.top=(t2.top > words)?words:t2.top;
t3.neg=t2.neg;
t3.max=t3.top;
// BN_print_fp(stdout,&s1); printf(" s1\n");
// BN_print_fp(stdout,&t2); printf(" middle value\n");
// BN_print_fp(stdout,&t3); printf(" low middle value\n");
BN_sub(&t1,&s1,&t3);
if (t1.neg)
{
//printf("neg fixup\n"); //BN_print_fp(stdout,&t1); printf(" before\n");
BN_lshift(&t2,BN_value_one(),words*32);
BN_add(&t1,&t2,&t1);
BN_mask_bits(&t1,words*32);
// BN_print_fp(stdout,&t1); printf(" after\n");
}
/* al*bl == high(al*bl)<<words+s0 */
BN_lshift(&t1,&t1,words*32);
BN_add(&t1,&t1,&s0);
/* We now have
* al*bl - t1
* (al-ah)*(bh-bl)+ah*bh - m
* ah*bh - h
*/
BN_copy(r,&t1);
BN_mask_bits(r,words*32*2);
/*BN_lshift(&m,&m,words*/
BN_free(&t1); BN_free(&t2);
BN_free(&m); BN_free(&h);
}
int BN_mod_mul_montgomery(r,a,b,mont,ctx)
BIGNUM *r,*a,*b;
BN_MONT_CTX *mont;
BN_CTX *ctx;
{
BIGNUM *tmp;
tmp= &(ctx->bn[ctx->tos++]);
if (a == b)
{
if (!BN_sqr(tmp,a,ctx)) goto err;
}
else
{
if (!BN_mul(tmp,a,b)) goto err;
}
/* reduce from aRR to aR */
if (!BN_from_montgomery(r,tmp,mont,ctx)) goto err;
ctx->tos--;
return(1);
err:
return(0);
}
int BN_from_montgomery(r,a,mont,ctx)
BIGNUM *r;
BIGNUM *a;
BN_MONT_CTX *mont;
BN_CTX *ctx;
{
BIGNUM z1;
BIGNUM *t1,*t2;
BN_ULONG *ap,*bp,*rp;
int j,i,bl,al;
BN_init(&z1);
t1= &(ctx->bn[ctx->tos]);
t2= &(ctx->bn[ctx->tos+1]);
if (!BN_copy(t1,a)) goto err;
/* can cheat */
BN_mask_bits(t1,mont->ri);
if (!BN_mul(t2,t1,mont->Ni)) goto err;
BN_mask_bits(t2,mont->ri);
if (!BN_mul(t1,t2,mont->N)) goto err;
if (!BN_add(t2,t1,a)) goto err;
/* At this point, t2 has the bottom ri bits set to zero.
* This means that the bottom ri bits == the 1^ri minus the bottom
* ri bits of a.
* This means that only the bits above 'ri' in a need to be added,
* and XXXXXXXXXXXXXXXXXXXXXXXX
*/
BN_print_fp(stdout,t2); printf("\n");
BN_rshift(r,t2,mont->ri);
if (BN_ucmp(r,mont->N) >= 0)
BN_usub(r,r,mont->N);
return(1);
err:
return(0);
}
int BN_MONT_CTX_set(mont,mod,ctx)
BN_MONT_CTX *mont;
BIGNUM *mod;
BN_CTX *ctx;
{
BIGNUM *Ri=NULL,*R=NULL;
if (mont->RR == NULL) mont->RR=BN_new();
if (mont->N == NULL) mont->N=BN_new();
R=mont->RR; /* grab RR as a temp */
BN_copy(mont->N,mod); /* Set N */
mont->ri=(BN_num_bits(mod)+(BN_BITS2-1))/BN_BITS2*BN_BITS2;
BN_lshift(R,BN_value_one(),mont->ri); /* R */
if ((Ri=BN_mod_inverse(NULL,R,mod,ctx)) == NULL) goto err;/* Ri */
BN_lshift(Ri,Ri,mont->ri); /* R*Ri */
BN_usub(Ri,Ri,BN_value_one()); /* R*Ri - 1 */
BN_div(Ri,NULL,Ri,mod,ctx);
if (mont->Ni != NULL) BN_free(mont->Ni);
mont->Ni=Ri; /* Ni=(R*Ri-1)/N */
/* setup RR for conversions */
BN_lshift(mont->RR,BN_value_one(),mont->ri*2);
BN_mod(mont->RR,mont->RR,mont->N,ctx);
return(1);
err:
return(0);
}
#endif