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Diffstat (limited to 'crypto/bn/bn_exp.c')
-rw-r--r--crypto/bn/bn_exp.c146
1 files changed, 81 insertions, 65 deletions
diff --git a/crypto/bn/bn_exp.c b/crypto/bn/bn_exp.c
index c056a5083f..44f47e7eb2 100644
--- a/crypto/bn/bn_exp.c
+++ b/crypto/bn/bn_exp.c
@@ -60,6 +60,8 @@
#include "cryptlib.h"
#include "bn_lcl.h"
+#define TABLE_SIZE 16
+
/* slow but works */
int BN_mod_mul(ret, a, b, m, ctx)
BIGNUM *ret;
@@ -71,11 +73,15 @@ BN_CTX *ctx;
BIGNUM *t;
int r=0;
- t=ctx->bn[ctx->tos++];
+ bn_check_top(a);
+ bn_check_top(b);
+ bn_check_top(m);
+
+ t= &(ctx->bn[ctx->tos++]);
if (a == b)
{ if (!BN_sqr(t,a,ctx)) goto err; }
else
- { if (!BN_mul(t,a,b)) goto err; }
+ { if (!BN_mul(t,a,b,ctx)) goto err; }
if (!BN_mod(ret,t,m,ctx)) goto err;
r=1;
err:
@@ -92,8 +98,8 @@ BN_CTX *ctx;
int i,bits,ret=0;
BIGNUM *v,*tmp;
- v=ctx->bn[ctx->tos++];
- tmp=ctx->bn[ctx->tos++];
+ v= &(ctx->bn[ctx->tos++]);
+ tmp= &(ctx->bn[ctx->tos++]);
if (BN_copy(v,a) == NULL) goto err;
bits=BN_num_bits(p);
@@ -108,7 +114,7 @@ BN_CTX *ctx;
if (!BN_mod(v,tmp,m,ctx)) goto err;
if (BN_is_bit_set(p,i))
{
- if (!BN_mul(tmp,r,v)) goto err;
+ if (!BN_mul(tmp,r,v,ctx)) goto err;
if (!BN_mod(r,tmp,m,ctx)) goto err;
}
}
@@ -128,8 +134,8 @@ BN_CTX *ctx;
int i,bits,ret=0;
BIGNUM *v,*tmp;
- v=ctx->bn[ctx->tos++];
- tmp=ctx->bn[ctx->tos++];
+ v= &(ctx->bn[ctx->tos++]);
+ tmp= &(ctx->bn[ctx->tos++]);
if (BN_copy(v,a) == NULL) goto err;
bits=BN_num_bits(p);
@@ -143,7 +149,7 @@ BN_CTX *ctx;
if (!BN_sqr(tmp,v,ctx)) goto err;
if (BN_is_bit_set(p,i))
{
- if (!BN_mul(tmp,r,v)) goto err;
+ if (!BN_mul(tmp,r,v,ctx)) goto err;
}
}
ret=1;
@@ -161,6 +167,10 @@ BN_CTX *ctx;
{
int ret;
+ bn_check_top(a);
+ bn_check_top(p);
+ bn_check_top(m);
+
#ifdef MONT_MUL_MOD
/* I have finally been able to take out this pre-condition of
* the top bit being set. It was caused by an error in BN_div
@@ -189,13 +199,13 @@ BIGNUM *p;
BIGNUM *m;
BN_CTX *ctx;
{
- int nb,i,j,bits,ret=0,wstart,wend,window,wvalue;
- int start=1;
- BIGNUM *d,*aa;
- BIGNUM *val[16];
+ int i,j,bits,ret=0,wstart,wend,window,wvalue;
+ int start=1,ts=0;
+ BIGNUM *aa;
+ BIGNUM val[TABLE_SIZE];
+ BN_RECP_CTX recp;
- d=ctx->bn[ctx->tos++];
- aa=ctx->bn[ctx->tos++];
+ aa= &(ctx->bn[ctx->tos++]);
bits=BN_num_bits(p);
if (bits == 0)
@@ -203,12 +213,14 @@ BN_CTX *ctx;
BN_one(r);
return(1);
}
- nb=BN_reciprocal(d,m,ctx);
- if (nb == -1) goto err;
+ BN_RECP_CTX_init(&recp);
+ if (BN_RECP_CTX_set(&recp,m,ctx) <= 0) goto err;
+
+ BN_init(&(val[0]));
+ ts=1;
- val[0]=BN_new();
- if (!BN_mod(val[0],a,m,ctx)) goto err; /* 1 */
- if (!BN_mod_mul_reciprocal(aa,val[0],val[0],m,d,nb,ctx))
+ if (!BN_mod(&(val[0]),a,m,ctx)) goto err; /* 1 */
+ if (!BN_mod_mul_reciprocal(aa,&(val[0]),&(val[0]),&recp,ctx))
goto err; /* 2 */
if (bits <= 17) /* This is probably 3 or 0x10001, so just do singles */
@@ -223,12 +235,11 @@ BN_CTX *ctx;
j=1<<(window-1);
for (i=1; i<j; i++)
{
- val[i]=BN_new();
- if (!BN_mod_mul_reciprocal(val[i],val[i-1],aa,m,d,nb,ctx))
+ BN_init(&val[i]);
+ if (!BN_mod_mul_reciprocal(&(val[i]),&(val[i-1]),aa,&recp,ctx))
goto err;
}
- for (; i<16; i++)
- val[i]=NULL;
+ ts=i;
start=1; /* This is used to avoid multiplication etc
* when there is only the value '1' in the
@@ -244,7 +255,7 @@ BN_CTX *ctx;
if (BN_is_bit_set(p,wstart) == 0)
{
if (!start)
- if (!BN_mod_mul_reciprocal(r,r,r,m,d,nb,ctx))
+ if (!BN_mod_mul_reciprocal(r,r,r,&recp,ctx))
goto err;
if (wstart == 0) break;
wstart--;
@@ -274,12 +285,12 @@ BN_CTX *ctx;
if (!start)
for (i=0; i<j; i++)
{
- if (!BN_mod_mul_reciprocal(r,r,r,m,d,nb,ctx))
+ if (!BN_mod_mul_reciprocal(r,r,r,&recp,ctx))
goto err;
}
/* wvalue will be an odd number < 2^window */
- if (!BN_mod_mul_reciprocal(r,r,val[wvalue>>1],m,d,nb,ctx))
+ if (!BN_mod_mul_reciprocal(r,r,&(val[wvalue>>1]),&recp,ctx))
goto err;
/* move the 'window' down further */
@@ -290,35 +301,40 @@ BN_CTX *ctx;
}
ret=1;
err:
- ctx->tos-=2;
- for (i=0; i<16; i++)
- if (val[i] != NULL) BN_clear_free(val[i]);
+ ctx->tos--;
+ for (i=0; i<ts; i++)
+ BN_clear_free(&(val[i]));
+ BN_RECP_CTX_free(&recp);
return(ret);
}
/* #endif */
/* #ifdef MONT_MUL_MOD */
-int BN_mod_exp_mont(r,a,p,m,ctx,in_mont)
-BIGNUM *r;
+int BN_mod_exp_mont(rr,a,p,m,ctx,in_mont)
+BIGNUM *rr;
BIGNUM *a;
BIGNUM *p;
BIGNUM *m;
BN_CTX *ctx;
BN_MONT_CTX *in_mont;
{
-#define TABLE_SIZE 16
int i,j,bits,ret=0,wstart,wend,window,wvalue;
- int start=1;
- BIGNUM *d,*aa;
- BIGNUM *val[TABLE_SIZE];
+ int start=1,ts=0;
+ BIGNUM *d,*aa,*r;
+ BIGNUM val[TABLE_SIZE];
BN_MONT_CTX *mont=NULL;
+ bn_check_top(a);
+ bn_check_top(p);
+ bn_check_top(m);
+
if (!(m->d[0] & 1))
{
BNerr(BN_F_BN_MOD_EXP_MONT,BN_R_CALLED_WITH_EVEN_MODULUS);
return(0);
}
- d=ctx->bn[ctx->tos++];
+ d= &(ctx->bn[ctx->tos++]);
+ r= &(ctx->bn[ctx->tos++]);
bits=BN_num_bits(p);
if (bits == 0)
{
@@ -339,22 +355,23 @@ BN_MONT_CTX *in_mont;
if (!BN_MONT_CTX_set(mont,m,ctx)) goto err;
}
- val[0]=BN_new();
+ BN_init(&val[0]);
+ ts=1;
if (BN_ucmp(a,m) >= 0)
{
- BN_mod(val[0],a,m,ctx);
- aa=val[0];
+ BN_mod(&(val[0]),a,m,ctx);
+ aa= &(val[0]);
}
else
aa=a;
- if (!BN_to_montgomery(val[0],aa,mont,ctx)) goto err; /* 1 */
- if (!BN_mod_mul_montgomery(d,val[0],val[0],mont,ctx)) goto err; /* 2 */
+ if (!BN_to_montgomery(&(val[0]),aa,mont,ctx)) goto err; /* 1 */
+ if (!BN_mod_mul_montgomery(d,&(val[0]),&(val[0]),mont,ctx)) goto err; /* 2 */
if (bits <= 20) /* This is probably 3 or 0x10001, so just do singles */
window=1;
- else if (bits > 250)
+ else if (bits >= 256)
window=5; /* max size of window */
- else if (bits >= 120)
+ else if (bits >= 128)
window=4;
else
window=3;
@@ -362,12 +379,11 @@ BN_MONT_CTX *in_mont;
j=1<<(window-1);
for (i=1; i<j; i++)
{
- val[i]=BN_new();
- if (!BN_mod_mul_montgomery(val[i],val[i-1],d,mont,ctx))
+ BN_init(&(val[i]));
+ if (!BN_mod_mul_montgomery(&(val[i]),&(val[i-1]),d,mont,ctx))
goto err;
}
- for (; i<TABLE_SIZE; i++)
- val[i]=NULL;
+ ts=i;
start=1; /* This is used to avoid multiplication etc
* when there is only the value '1' in the
@@ -419,7 +435,7 @@ BN_MONT_CTX *in_mont;
}
/* wvalue will be an odd number < 2^window */
- if (!BN_mod_mul_montgomery(r,r,val[wvalue>>1],mont,ctx))
+ if (!BN_mod_mul_montgomery(r,r,&(val[wvalue>>1]),mont,ctx))
goto err;
/* move the 'window' down further */
@@ -428,13 +444,13 @@ BN_MONT_CTX *in_mont;
start=0;
if (wstart < 0) break;
}
- BN_from_montgomery(r,r,mont,ctx);
+ BN_from_montgomery(rr,r,mont,ctx);
ret=1;
err:
if ((in_mont == NULL) && (mont != NULL)) BN_MONT_CTX_free(mont);
- ctx->tos--;
- for (i=0; i<TABLE_SIZE; i++)
- if (val[i] != NULL) BN_clear_free(val[i]);
+ ctx->tos-=2;
+ for (i=0; i<ts; i++)
+ BN_clear_free(&(val[i]));
return(ret);
}
/* #endif */
@@ -447,12 +463,12 @@ BIGNUM *p;
BIGNUM *m;
BN_CTX *ctx;
{
- int i,j,bits,ret=0,wstart,wend,window,wvalue;
+ int i,j,bits,ret=0,wstart,wend,window,wvalue,ts=0;
int start=1;
BIGNUM *d;
- BIGNUM *val[16];
+ BIGNUM val[TABLE_SIZE];
- d=ctx->bn[ctx->tos++];
+ d= &(ctx->bn[ctx->tos++]);
bits=BN_num_bits(p);
if (bits == 0)
@@ -461,9 +477,10 @@ BN_CTX *ctx;
return(1);
}
- val[0]=BN_new();
- if (!BN_mod(val[0],a,m,ctx)) goto err; /* 1 */
- if (!BN_mod_mul(d,val[0],val[0],m,ctx))
+ BN_init(&(val[0]));
+ ts=1;
+ if (!BN_mod(&(val[0]),a,m,ctx)) goto err; /* 1 */
+ if (!BN_mod_mul(d,&(val[0]),&(val[0]),m,ctx))
goto err; /* 2 */
if (bits <= 17) /* This is probably 3 or 0x10001, so just do singles */
@@ -478,12 +495,11 @@ BN_CTX *ctx;
j=1<<(window-1);
for (i=1; i<j; i++)
{
- val[i]=BN_new();
- if (!BN_mod_mul(val[i],val[i-1],d,m,ctx))
+ BN_init(&(val[i]));
+ if (!BN_mod_mul(&(val[i]),&(val[i-1]),d,m,ctx))
goto err;
}
- for (; i<16; i++)
- val[i]=NULL;
+ ts=i;
start=1; /* This is used to avoid multiplication etc
* when there is only the value '1' in the
@@ -534,7 +550,7 @@ BN_CTX *ctx;
}
/* wvalue will be an odd number < 2^window */
- if (!BN_mod_mul(r,r,val[wvalue>>1],m,ctx))
+ if (!BN_mod_mul(r,r,&(val[wvalue>>1]),m,ctx))
goto err;
/* move the 'window' down further */
@@ -546,8 +562,8 @@ BN_CTX *ctx;
ret=1;
err:
ctx->tos--;
- for (i=0; i<16; i++)
- if (val[i] != NULL) BN_clear_free(val[i]);
+ for (i=0; i<ts; i++)
+ BN_clear_free(&(val[i]));
return(ret);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-16 11:50:26 +0000