X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=crypto%2Fbn%2Fbn_exp.c;h=2df1614ada17047acfcf0affab26d39169903a0c;hb=f18a93ab04f248de45a8bcdded9b91880c690dbd;hp=0a0db370c35bcdced30a5d63ecf339ec35e69c71;hpb=eda1f21f1af8b6f77327e7b37573af9c1ba73726;p=oweals%2Fopenssl.git

diff --git a/crypto/bn/bn_exp.c b/crypto/bn/bn_exp.c
index 0a0db370c3..2df1614ada 100644
--- a/crypto/bn/bn_exp.c
+++ b/crypto/bn/bn_exp.c
@@ -1,5 +1,5 @@
 /* crypto/bn/bn_exp.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
@@ -60,22 +60,23 @@
 #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;
-BIGNUM *a;
-BIGNUM *b;
-BIGNUM *m;
-BN_CTX *ctx;
+int BN_mod_mul(BIGNUM *ret, BIGNUM *a, BIGNUM *b, const BIGNUM *m, 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:
@@ -85,22 +86,20 @@ err:
 
 #if 0
 /* this one works - simple but works */
-int BN_mod_exp(r,a,p,m,ctx)
-BIGNUM *r,*a,*p,*m;
-BN_CTX *ctx;
+int BN_mod_exp(BIGNUM *r, BIGNUM *a, BIGNUM *p, BIGNUM *m, 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);
 
 	if (BN_is_odd(p))
 		{ if (BN_copy(r,a) == NULL) goto err; }
-	else	{ if (BN_one(r)) goto err; }
+	else	{ if (!BN_one(r)) goto err; }
 
 	for (i=1; i<bits; i++)
 		{
@@ -108,7 +107,7 @@ 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;
 			}
 		}
@@ -120,15 +119,50 @@ err:
 
 #endif
 
-int BN_mod_exp(r,a,p,m,ctx)
-BIGNUM *r;
-BIGNUM *a;
-BIGNUM *p;
-BIGNUM *m;
-BN_CTX *ctx;
+/* this one works - simple but works */
+int BN_exp(BIGNUM *r, BIGNUM *a, BIGNUM *p, BN_CTX *ctx)
+	{
+	int i,bits,ret=0,tos;
+	BIGNUM *v,*rr;
+
+	tos=ctx->tos;
+	v= &(ctx->bn[ctx->tos++]);
+	if ((r == a) || (r == p))
+		rr= &(ctx->bn[ctx->tos++]);
+	else
+		rr=r;
+
+	if (BN_copy(v,a) == NULL) goto err;
+	bits=BN_num_bits(p);
+
+	if (BN_is_odd(p))
+		{ if (BN_copy(rr,a) == NULL) goto err; }
+	else	{ if (!BN_one(rr)) goto err; }
+
+	for (i=1; i<bits; i++)
+		{
+		if (!BN_sqr(v,v,ctx)) goto err;
+		if (BN_is_bit_set(p,i))
+			{
+			if (!BN_mul(rr,rr,v,ctx)) goto err;
+			}
+		}
+	ret=1;
+err:
+	ctx->tos=tos;
+	if (r != rr) BN_copy(r,rr);
+	return(ret);
+	}
+
+int BN_mod_exp(BIGNUM *r, BIGNUM *a, const BIGNUM *p, const BIGNUM *m,
+	       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
@@ -137,7 +171,7 @@ BN_CTX *ctx;
 /*	if ((m->d[m->top-1]&BN_TBIT) && BN_is_odd(m)) */
 
 	if (BN_is_odd(m))
-		{ ret=BN_mod_exp_mont(r,a,p,m,ctx); }
+		{ ret=BN_mod_exp_mont(r,a,p,m,ctx,NULL); }
 	else
 #endif
 #ifdef RECP_MUL_MOD
@@ -150,20 +184,16 @@ BN_CTX *ctx;
 	}
 
 /* #ifdef RECP_MUL_MOD */
-int BN_mod_exp_recp(r,a,p,m,ctx)
-BIGNUM *r;
-BIGNUM *a;
-BIGNUM *p;
-BIGNUM *m;
-BN_CTX *ctx;
+int BN_mod_exp_recp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
+		    const 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)
@@ -171,12 +201,14 @@ 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;
 
-	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))
+	BN_init(&(val[0]));
+	ts=1;
+
+	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 */
@@ -191,12 +223,11 @@ 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
@@ -212,7 +243,7 @@ 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--;
@@ -242,12 +273,12 @@ 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 */
@@ -258,33 +289,36 @@ 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)
-BIGNUM *r;
-BIGNUM *a;
-BIGNUM *p;
-BIGNUM *m;
-BN_CTX *ctx;
+int BN_mod_exp_mont(BIGNUM *rr, BIGNUM *a, const BIGNUM *p,
+		    const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *in_mont)
 	{
 	int i,j,bits,ret=0,wstart,wend,window,wvalue;
-	int start=1;
-	BIGNUM *d,*aa;
-	BIGNUM *val[16];
+	int start=1,ts=0;
+	BIGNUM *d,*r;
+	BIGNUM *aa;
+	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)
 		{
@@ -295,21 +329,29 @@ BN_CTX *ctx;
 	/* If this is not done, things will break in the montgomery
 	 * part */
 
-	if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
-	if (!BN_MONT_CTX_set(mont,m,ctx)) goto err;
+#if 1
+	if (in_mont != NULL)
+		mont=in_mont;
+	else
+#endif
+		{
+		if ((mont=BN_MONT_CTX_new()) == NULL) goto err;
+		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 <= 17) /* This is probably 3 or 0x10001, so just do singles */
+	if (bits <= 20) /* This is probably 3 or 0x10001, so just do singles */
 		window=1;
 	else if (bits >= 256)
 		window=5;	/* max size of window */
@@ -321,12 +363,11 @@ BN_CTX *ctx;
 	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<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
@@ -341,8 +382,10 @@ BN_CTX *ctx;
 		if (BN_is_bit_set(p,wstart) == 0)
 			{
 			if (!start)
+				{
 				if (!BN_mod_mul_montgomery(r,r,r,mont,ctx))
 				goto err;
+				}
 			if (wstart == 0) break;
 			wstart--;
 			continue;
@@ -376,7 +419,7 @@ BN_CTX *ctx;
 				}
 		
 		/* 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 */
@@ -385,31 +428,27 @@ BN_CTX *ctx;
 		start=0;
 		if (wstart < 0) break;
 		}
-	BN_from_montgomery(r,r,mont,ctx);
+	BN_from_montgomery(rr,r,mont,ctx);
 	ret=1;
 err:
-	if (mont != NULL) BN_MONT_CTX_free(mont);
-	ctx->tos--;
-	for (i=0; i<16; i++)
-		if (val[i] != NULL) BN_clear_free(val[i]);
+	if ((in_mont == NULL) && (mont != NULL)) BN_MONT_CTX_free(mont);
+	ctx->tos-=2;
+	for (i=0; i<ts; i++)
+		BN_clear_free(&(val[i]));
 	return(ret);
 	}
 /* #endif */
 
 /* The old fallback, simple version :-) */
-int BN_mod_exp_simple(r,a,p,m,ctx)
-BIGNUM *r;
-BIGNUM *a;
-BIGNUM *p;
-BIGNUM *m;
-BN_CTX *ctx;
+int BN_mod_exp_simple(BIGNUM *r, BIGNUM *a, 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)
@@ -418,9 +457,10 @@ 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 */
@@ -435,12 +475,11 @@ 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
@@ -491,7 +530,7 @@ 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 */
@@ -503,8 +542,8 @@ 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);
 	}