X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fbn%2Fbn_shift.c;h=b3206028713c44d6faa31cc3460f2f308a552a82;hp=c4d301afc4675b7739ede6517f3cebcde52a285a;hb=38d1b3cc0271008b8bd130a2c4b442775b028a08;hpb=b764f82c645639ce794f28ef92e749066dd2caa6 diff --git a/crypto/bn/bn_shift.c b/crypto/bn/bn_shift.c index c4d301afc4..b320602871 100644 --- a/crypto/bn/bn_shift.c +++ b/crypto/bn/bn_shift.c @@ -1,220 +1,173 @@ -/* crypto/bn/bn_shift.c */ -/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) - * All rights reserved. +/* + * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. * - * This package is an SSL implementation written - * by Eric Young (eay@cryptsoft.com). - * The implementation was written so as to conform with Netscapes SSL. - * - * This library is free for commercial and non-commercial use as long as - * the following conditions are aheared to. The following conditions - * apply to all code found in this distribution, be it the RC4, RSA, - * lhash, DES, etc., code; not just the SSL code. The SSL documentation - * included with this distribution is covered by the same copyright terms - * except that the holder is Tim Hudson (tjh@cryptsoft.com). - * - * Copyright remains Eric Young's, and as such any Copyright notices in - * the code are not to be removed. - * If this package is used in a product, Eric Young should be given attribution - * as the author of the parts of the library 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 cryptographic software written by - * Eric Young (eay@cryptsoft.com)" - * The word 'cryptographic' can be left out if the rouines from the library - * being used are not cryptographic related :-). - * 4. If you include any Windows specific code (or a derivative thereof) from - * the apps directory (application code) you must include an acknowledgement: - * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" - * - * 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.] + * Licensed under the OpenSSL license (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html */ -#include -#include "cryptlib.h" +#include "internal/cryptlib.h" #include "bn_lcl.h" int BN_lshift1(BIGNUM *r, const BIGNUM *a) - { - register BN_ULONG *ap,*rp,t,c; - int i; - - bn_check_top(r); - bn_check_top(a); - - if (r != a) - { - r->neg=a->neg; - if (bn_wexpand(r,a->top+1) == NULL) return(0); - r->top=a->top; - } - else - { - if (bn_wexpand(r,a->top+1) == NULL) return(0); - } - ap=a->d; - rp=r->d; - c=0; - for (i=0; itop; i++) - { - t= *(ap++); - *(rp++)=((t<<1)|c)&BN_MASK2; - c=(t & BN_TBIT)?1:0; - } - if (c) - { - *rp=1; - r->top++; - } - bn_check_top(r); - return(1); - } +{ + register BN_ULONG *ap, *rp, t, c; + int i; + + bn_check_top(r); + bn_check_top(a); + + if (r != a) { + r->neg = a->neg; + if (bn_wexpand(r, a->top + 1) == NULL) + return (0); + r->top = a->top; + } else { + if (bn_wexpand(r, a->top + 1) == NULL) + return (0); + } + ap = a->d; + rp = r->d; + c = 0; + for (i = 0; i < a->top; i++) { + t = *(ap++); + *(rp++) = ((t << 1) | c) & BN_MASK2; + c = (t & BN_TBIT) ? 1 : 0; + } + if (c) { + *rp = 1; + r->top++; + } + bn_check_top(r); + return (1); +} int BN_rshift1(BIGNUM *r, const BIGNUM *a) - { - BN_ULONG *ap,*rp,t,c; - int i; - - bn_check_top(r); - bn_check_top(a); - - if (BN_is_zero(a)) - { - BN_zero(r); - return(1); - } - if (a != r) - { - if (bn_wexpand(r,a->top) == NULL) return(0); - r->top=a->top; - r->neg=a->neg; - } - ap=a->d; - rp=r->d; - c=0; - for (i=a->top-1; i>=0; i--) - { - t=ap[i]; - rp[i]=((t>>1)&BN_MASK2)|c; - c=(t&1)?BN_TBIT:0; - } - bn_correct_top(r); - bn_check_top(r); - return(1); - } +{ + BN_ULONG *ap, *rp, t, c; + int i, j; + + bn_check_top(r); + bn_check_top(a); + + if (BN_is_zero(a)) { + BN_zero(r); + return (1); + } + i = a->top; + ap = a->d; + j = i - (ap[i - 1] == 1); + if (a != r) { + if (bn_wexpand(r, j) == NULL) + return (0); + r->neg = a->neg; + } + rp = r->d; + t = ap[--i]; + c = (t & 1) ? BN_TBIT : 0; + if (t >>= 1) + rp[i] = t; + while (i > 0) { + t = ap[--i]; + rp[i] = ((t >> 1) & BN_MASK2) | c; + c = (t & 1) ? BN_TBIT : 0; + } + r->top = j; + bn_check_top(r); + return (1); +} int BN_lshift(BIGNUM *r, const BIGNUM *a, int n) - { - int i,nw,lb,rb; - BN_ULONG *t,*f; - BN_ULONG l; - - bn_check_top(r); - bn_check_top(a); - - r->neg=a->neg; - nw=n/BN_BITS2; - if (bn_wexpand(r,a->top+nw+1) == NULL) return(0); - lb=n%BN_BITS2; - rb=BN_BITS2-lb; - f=a->d; - t=r->d; - t[a->top+nw]=0; - if (lb == 0) - for (i=a->top-1; i>=0; i--) - t[nw+i]=f[i]; - else - for (i=a->top-1; i>=0; i--) - { - l=f[i]; - t[nw+i+1]|=(l>>rb)&BN_MASK2; - t[nw+i]=(l<top=a->top+nw+1; - bn_correct_top(r); - bn_check_top(r); - return(1); - } +{ + int i, nw, lb, rb; + BN_ULONG *t, *f; + BN_ULONG l; + + bn_check_top(r); + bn_check_top(a); + + if (n < 0) { + BNerr(BN_F_BN_LSHIFT, BN_R_INVALID_SHIFT); + return 0; + } + + nw = n / BN_BITS2; + if (bn_wexpand(r, a->top + nw + 1) == NULL) + return (0); + r->neg = a->neg; + lb = n % BN_BITS2; + rb = BN_BITS2 - lb; + f = a->d; + t = r->d; + t[a->top + nw] = 0; + if (lb == 0) + for (i = a->top - 1; i >= 0; i--) + t[nw + i] = f[i]; + else + for (i = a->top - 1; i >= 0; i--) { + l = f[i]; + t[nw + i + 1] |= (l >> rb) & BN_MASK2; + t[nw + i] = (l << lb) & BN_MASK2; + } + memset(t, 0, sizeof(*t) * nw); + r->top = a->top + nw + 1; + bn_correct_top(r); + bn_check_top(r); + return (1); +} int BN_rshift(BIGNUM *r, const BIGNUM *a, int n) - { - int i,j,nw,lb,rb; - BN_ULONG *t,*f; - BN_ULONG l,tmp; - - bn_check_top(r); - bn_check_top(a); - - nw=n/BN_BITS2; - rb=n%BN_BITS2; - lb=BN_BITS2-rb; - if (nw >= a->top || a->top == 0) - { - BN_zero(r); - return(1); - } - if (r != a) - { - r->neg=a->neg; - if (bn_wexpand(r,a->top-nw+1) == NULL) return(0); - } - else - { - if (n == 0) - return 1; /* or the copying loop will go berserk */ - } - - f= &(a->d[nw]); - t=r->d; - j=a->top-nw; - r->top=j; - - if (rb == 0) - { - for (i=j; i != 0; i--) - *(t++)= *(f++); - } - else - { - l= *(f++); - for (i=j-1; i != 0; i--) - { - tmp =(l>>rb)&BN_MASK2; - l= *(f++); - *(t++) =(tmp|(l<>rb)&BN_MASK2; - } - bn_correct_top(r); - bn_check_top(r); - return(1); - } +{ + int i, j, nw, lb, rb; + BN_ULONG *t, *f; + BN_ULONG l, tmp; + + bn_check_top(r); + bn_check_top(a); + + if (n < 0) { + BNerr(BN_F_BN_RSHIFT, BN_R_INVALID_SHIFT); + return 0; + } + + nw = n / BN_BITS2; + rb = n % BN_BITS2; + lb = BN_BITS2 - rb; + if (nw >= a->top || a->top == 0) { + BN_zero(r); + return (1); + } + i = (BN_num_bits(a) - n + (BN_BITS2 - 1)) / BN_BITS2; + if (r != a) { + if (bn_wexpand(r, i) == NULL) + return (0); + r->neg = a->neg; + } else { + if (n == 0) + return 1; /* or the copying loop will go berserk */ + } + + f = &(a->d[nw]); + t = r->d; + j = a->top - nw; + r->top = i; + + if (rb == 0) { + for (i = j; i != 0; i--) + *(t++) = *(f++); + } else { + l = *(f++); + for (i = j - 1; i != 0; i--) { + tmp = (l >> rb) & BN_MASK2; + l = *(f++); + *(t++) = (tmp | (l << lb)) & BN_MASK2; + } + if ((l = (l >> rb) & BN_MASK2)) + *(t) = l; + } + if (!r->top) + r->neg = 0; /* don't allow negative zero */ + bn_check_top(r); + return (1); +}