/* lib/rsa/bn_mul.c *//* Copyright (C) 1995 Eric Young (eay@mincom.oz.au) * All rights reserved. *  * This file is part of an SSL implementation written * by Eric Young (eay@mincom.oz.au). * The implementation was written so as to conform with Netscapes SSL * specification.  This library and applications are * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE * as long as the following conditions are aheared to. *  * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed.  If this code is used in a product, * Eric Young should be given attribution as the author of the parts used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. *  * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright *    notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright *    notice, this list of conditions and the following disclaimer in the *    documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software *    must display the following acknowledgement: *    This product includes software developed by Eric Young (eay@mincom.oz.au) *  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. *  * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed.  i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */#include <stdio.h>#include "bn.h"#ifdef IRIX_CC_BUGunsigned long null(a)unsigned long a;	{	return(a);	}#endif#define			LBITS(a)	((a)&MASK2l)#define			HBITS(a)	(((a)>>BITS4)&MASK2l)#define			L2HBITS(a)	(((a)&MASK2l)<<BITS4)/* r must be different to a and b */int bn_mul(r, a, b)BIGNUM *r;BIGNUM *a;BIGNUM *b;	{	int i,j;	int max;	BN_ULONG *ap,*bp,*rp;	bn_zero(r);	if ((a->top == 0) || (b->top == 0))		{		r->top=0;		return(1);		}	max=(a->top+b->top+1);	if (bn_expand(r,(max+1)*BITS2) == NULL) return(0);	r->top=max;	r->neg=a->neg^b->neg;	bp=b->d;	for (i=0; i<b->top; i++)		{#ifndef RSA_LLONG#ifdef IRIX_CC_BUG		unsigned long dummy;#endif		BN_ULONG bl,bh,c1;		c1=0;		rp= &(r->d[i]);		ap=a->d;		bh =*(bp++);		bl=LBITS(bh);		bh=HBITS(bh);		for (j=a->top; j; j--)			{			register BN_ULONG l,h,m,m1;						h= *(ap++);			l =LBITS(h);			h =HBITS(h);			m =bh*l;		/* m2 = h(a)*l(b) */			l =bl*l;		/* l = l(a)*l(b) */			m1=bl*h;		/* m3= l(a)*h(b) */			h =bh*h;		/* h = h(m)*h(b) */			m+=m1;			/* m2 = m2 + m3 */			if ((m&MASK2) < m1) h+=L2HBITS(1L);			h+=HBITS(m);		/* H = h + h(M) */			m1=L2HBITS(m);			l+=m1; if ((l&MASK2) < m1) h++;			/* non-multiply part */			m1= *rp;			l+=m1; if ((l&MASK2) < m1) h++;			l+=c1; if ((l&MASK2) < c1) h++;			c1=h&MASK2;#ifdef IRIX_CC_BUG			rp[0]=null(l&MASK2);			rp++;#else			*(rp++)=l&MASK2;#endif			}		*rp = c1;#else		BN_ULONG m,c1;		BN_ULONG *lrp;		m =*(bp++);		rp= &(r->d[i]);		j=a->top;		lrp=rp+a->top;		ap= a->d;		c1=0;		for (;;)			{			BN_ULLONG t;#define	L	((BN_ULONG)t&MASK2)#define	H	((BN_ULONG)(t>>BITS2)&MASK2)#ifndef POINTER#define mul(n)		t=(BN_ULLONG)m* ap[n] + rp[n] + c1; \			rp[n]=L; \			c1=H; \			if (--j == 0) break;#else#define mul(n)		t=(BN_ULLONG)m* *(ap++) + *rp + c1; \			*(rp++)=L; \			c1=H; \			if (--j == 0) break;#endif			mul(0); mul(1); mul(2); mul(3);			mul(4); mul(5); mul(6); mul(7);#ifndef POINTER			ap+=8;			rp+=8;#endif			}		*lrp=c1;#endif		}	bn_fix_top(r);	return(1);	}