1*0Sstevel@tonic-gate /* crypto/bn/bn_shift.c */ 2*0Sstevel@tonic-gate /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3*0Sstevel@tonic-gate * All rights reserved. 4*0Sstevel@tonic-gate * 5*0Sstevel@tonic-gate * This package is an SSL implementation written 6*0Sstevel@tonic-gate * by Eric Young (eay@cryptsoft.com). 7*0Sstevel@tonic-gate * The implementation was written so as to conform with Netscapes SSL. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * This library is free for commercial and non-commercial use as long as 10*0Sstevel@tonic-gate * the following conditions are aheared to. The following conditions 11*0Sstevel@tonic-gate * apply to all code found in this distribution, be it the RC4, RSA, 12*0Sstevel@tonic-gate * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13*0Sstevel@tonic-gate * included with this distribution is covered by the same copyright terms 14*0Sstevel@tonic-gate * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15*0Sstevel@tonic-gate * 16*0Sstevel@tonic-gate * Copyright remains Eric Young's, and as such any Copyright notices in 17*0Sstevel@tonic-gate * the code are not to be removed. 18*0Sstevel@tonic-gate * If this package is used in a product, Eric Young should be given attribution 19*0Sstevel@tonic-gate * as the author of the parts of the library used. 20*0Sstevel@tonic-gate * This can be in the form of a textual message at program startup or 21*0Sstevel@tonic-gate * in documentation (online or textual) provided with the package. 22*0Sstevel@tonic-gate * 23*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without 24*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions 25*0Sstevel@tonic-gate * are met: 26*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the copyright 27*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer. 28*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright 29*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the 30*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution. 31*0Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software 32*0Sstevel@tonic-gate * must display the following acknowledgement: 33*0Sstevel@tonic-gate * "This product includes cryptographic software written by 34*0Sstevel@tonic-gate * Eric Young (eay@cryptsoft.com)" 35*0Sstevel@tonic-gate * The word 'cryptographic' can be left out if the rouines from the library 36*0Sstevel@tonic-gate * being used are not cryptographic related :-). 37*0Sstevel@tonic-gate * 4. If you include any Windows specific code (or a derivative thereof) from 38*0Sstevel@tonic-gate * the apps directory (application code) you must include an acknowledgement: 39*0Sstevel@tonic-gate * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40*0Sstevel@tonic-gate * 41*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42*0Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43*0Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44*0Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45*0Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46*0Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47*0Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48*0Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49*0Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50*0Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51*0Sstevel@tonic-gate * SUCH DAMAGE. 52*0Sstevel@tonic-gate * 53*0Sstevel@tonic-gate * The licence and distribution terms for any publically available version or 54*0Sstevel@tonic-gate * derivative of this code cannot be changed. i.e. this code cannot simply be 55*0Sstevel@tonic-gate * copied and put under another distribution licence 56*0Sstevel@tonic-gate * [including the GNU Public Licence.] 57*0Sstevel@tonic-gate */ 58*0Sstevel@tonic-gate 59*0Sstevel@tonic-gate #include <stdio.h> 60*0Sstevel@tonic-gate #include "cryptlib.h" 61*0Sstevel@tonic-gate #include "bn_lcl.h" 62*0Sstevel@tonic-gate 63*0Sstevel@tonic-gate int BN_lshift1(BIGNUM *r, const BIGNUM *a) 64*0Sstevel@tonic-gate { 65*0Sstevel@tonic-gate register BN_ULONG *ap,*rp,t,c; 66*0Sstevel@tonic-gate int i; 67*0Sstevel@tonic-gate 68*0Sstevel@tonic-gate if (r != a) 69*0Sstevel@tonic-gate { 70*0Sstevel@tonic-gate r->neg=a->neg; 71*0Sstevel@tonic-gate if (bn_wexpand(r,a->top+1) == NULL) return(0); 72*0Sstevel@tonic-gate r->top=a->top; 73*0Sstevel@tonic-gate } 74*0Sstevel@tonic-gate else 75*0Sstevel@tonic-gate { 76*0Sstevel@tonic-gate if (bn_wexpand(r,a->top+1) == NULL) return(0); 77*0Sstevel@tonic-gate } 78*0Sstevel@tonic-gate ap=a->d; 79*0Sstevel@tonic-gate rp=r->d; 80*0Sstevel@tonic-gate c=0; 81*0Sstevel@tonic-gate for (i=0; i<a->top; i++) 82*0Sstevel@tonic-gate { 83*0Sstevel@tonic-gate t= *(ap++); 84*0Sstevel@tonic-gate *(rp++)=((t<<1)|c)&BN_MASK2; 85*0Sstevel@tonic-gate c=(t & BN_TBIT)?1:0; 86*0Sstevel@tonic-gate } 87*0Sstevel@tonic-gate if (c) 88*0Sstevel@tonic-gate { 89*0Sstevel@tonic-gate *rp=1; 90*0Sstevel@tonic-gate r->top++; 91*0Sstevel@tonic-gate } 92*0Sstevel@tonic-gate return(1); 93*0Sstevel@tonic-gate } 94*0Sstevel@tonic-gate 95*0Sstevel@tonic-gate int BN_rshift1(BIGNUM *r, const BIGNUM *a) 96*0Sstevel@tonic-gate { 97*0Sstevel@tonic-gate BN_ULONG *ap,*rp,t,c; 98*0Sstevel@tonic-gate int i; 99*0Sstevel@tonic-gate 100*0Sstevel@tonic-gate if (BN_is_zero(a)) 101*0Sstevel@tonic-gate { 102*0Sstevel@tonic-gate BN_zero(r); 103*0Sstevel@tonic-gate return(1); 104*0Sstevel@tonic-gate } 105*0Sstevel@tonic-gate if (a != r) 106*0Sstevel@tonic-gate { 107*0Sstevel@tonic-gate if (bn_wexpand(r,a->top) == NULL) return(0); 108*0Sstevel@tonic-gate r->top=a->top; 109*0Sstevel@tonic-gate r->neg=a->neg; 110*0Sstevel@tonic-gate } 111*0Sstevel@tonic-gate ap=a->d; 112*0Sstevel@tonic-gate rp=r->d; 113*0Sstevel@tonic-gate c=0; 114*0Sstevel@tonic-gate for (i=a->top-1; i>=0; i--) 115*0Sstevel@tonic-gate { 116*0Sstevel@tonic-gate t=ap[i]; 117*0Sstevel@tonic-gate rp[i]=((t>>1)&BN_MASK2)|c; 118*0Sstevel@tonic-gate c=(t&1)?BN_TBIT:0; 119*0Sstevel@tonic-gate } 120*0Sstevel@tonic-gate bn_fix_top(r); 121*0Sstevel@tonic-gate return(1); 122*0Sstevel@tonic-gate } 123*0Sstevel@tonic-gate 124*0Sstevel@tonic-gate int BN_lshift(BIGNUM *r, const BIGNUM *a, int n) 125*0Sstevel@tonic-gate { 126*0Sstevel@tonic-gate int i,nw,lb,rb; 127*0Sstevel@tonic-gate BN_ULONG *t,*f; 128*0Sstevel@tonic-gate BN_ULONG l; 129*0Sstevel@tonic-gate 130*0Sstevel@tonic-gate r->neg=a->neg; 131*0Sstevel@tonic-gate nw=n/BN_BITS2; 132*0Sstevel@tonic-gate if (bn_wexpand(r,a->top+nw+1) == NULL) return(0); 133*0Sstevel@tonic-gate lb=n%BN_BITS2; 134*0Sstevel@tonic-gate rb=BN_BITS2-lb; 135*0Sstevel@tonic-gate f=a->d; 136*0Sstevel@tonic-gate t=r->d; 137*0Sstevel@tonic-gate t[a->top+nw]=0; 138*0Sstevel@tonic-gate if (lb == 0) 139*0Sstevel@tonic-gate for (i=a->top-1; i>=0; i--) 140*0Sstevel@tonic-gate t[nw+i]=f[i]; 141*0Sstevel@tonic-gate else 142*0Sstevel@tonic-gate for (i=a->top-1; i>=0; i--) 143*0Sstevel@tonic-gate { 144*0Sstevel@tonic-gate l=f[i]; 145*0Sstevel@tonic-gate t[nw+i+1]|=(l>>rb)&BN_MASK2; 146*0Sstevel@tonic-gate t[nw+i]=(l<<lb)&BN_MASK2; 147*0Sstevel@tonic-gate } 148*0Sstevel@tonic-gate memset(t,0,nw*sizeof(t[0])); 149*0Sstevel@tonic-gate /* for (i=0; i<nw; i++) 150*0Sstevel@tonic-gate t[i]=0;*/ 151*0Sstevel@tonic-gate r->top=a->top+nw+1; 152*0Sstevel@tonic-gate bn_fix_top(r); 153*0Sstevel@tonic-gate return(1); 154*0Sstevel@tonic-gate } 155*0Sstevel@tonic-gate 156*0Sstevel@tonic-gate int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) 157*0Sstevel@tonic-gate { 158*0Sstevel@tonic-gate int i,j,nw,lb,rb; 159*0Sstevel@tonic-gate BN_ULONG *t,*f; 160*0Sstevel@tonic-gate BN_ULONG l,tmp; 161*0Sstevel@tonic-gate 162*0Sstevel@tonic-gate nw=n/BN_BITS2; 163*0Sstevel@tonic-gate rb=n%BN_BITS2; 164*0Sstevel@tonic-gate lb=BN_BITS2-rb; 165*0Sstevel@tonic-gate if (nw > a->top || a->top == 0) 166*0Sstevel@tonic-gate { 167*0Sstevel@tonic-gate BN_zero(r); 168*0Sstevel@tonic-gate return(1); 169*0Sstevel@tonic-gate } 170*0Sstevel@tonic-gate if (r != a) 171*0Sstevel@tonic-gate { 172*0Sstevel@tonic-gate r->neg=a->neg; 173*0Sstevel@tonic-gate if (bn_wexpand(r,a->top-nw+1) == NULL) return(0); 174*0Sstevel@tonic-gate } 175*0Sstevel@tonic-gate else 176*0Sstevel@tonic-gate { 177*0Sstevel@tonic-gate if (n == 0) 178*0Sstevel@tonic-gate return 1; /* or the copying loop will go berserk */ 179*0Sstevel@tonic-gate } 180*0Sstevel@tonic-gate 181*0Sstevel@tonic-gate f= &(a->d[nw]); 182*0Sstevel@tonic-gate t=r->d; 183*0Sstevel@tonic-gate j=a->top-nw; 184*0Sstevel@tonic-gate r->top=j; 185*0Sstevel@tonic-gate 186*0Sstevel@tonic-gate if (rb == 0) 187*0Sstevel@tonic-gate { 188*0Sstevel@tonic-gate for (i=j+1; i > 0; i--) 189*0Sstevel@tonic-gate *(t++)= *(f++); 190*0Sstevel@tonic-gate } 191*0Sstevel@tonic-gate else 192*0Sstevel@tonic-gate { 193*0Sstevel@tonic-gate l= *(f++); 194*0Sstevel@tonic-gate for (i=1; i<j; i++) 195*0Sstevel@tonic-gate { 196*0Sstevel@tonic-gate tmp =(l>>rb)&BN_MASK2; 197*0Sstevel@tonic-gate l= *(f++); 198*0Sstevel@tonic-gate *(t++) =(tmp|(l<<lb))&BN_MASK2; 199*0Sstevel@tonic-gate } 200*0Sstevel@tonic-gate *(t++) =(l>>rb)&BN_MASK2; 201*0Sstevel@tonic-gate } 202*0Sstevel@tonic-gate *t=0; 203*0Sstevel@tonic-gate bn_fix_top(r); 204*0Sstevel@tonic-gate return(1); 205*0Sstevel@tonic-gate } 206