mirror of
https://github.com/pineappleEA/pineapple-src.git
synced 2024-12-12 01:08:25 -05:00
219 lines
5.7 KiB
C
219 lines
5.7 KiB
C
|
/* $OpenBSD: bn_shift.c,v 1.13 2014/10/28 07:35:58 jsg Exp $ */
|
||
|
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
|
||
|
* 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.]
|
||
|
*/
|
||
|
|
||
|
#include <stdio.h>
|
||
|
#include <string.h>
|
||
|
|
||
|
#include "bn_lcl.h"
|
||
|
|
||
|
int
|
||
|
BN_lshift1(BIGNUM *r, const BIGNUM *a)
|
||
|
{
|
||
|
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, 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 << lb) & BN_MASK2;
|
||
|
}
|
||
|
memset(t, 0, nw * sizeof(t[0]));
|
||
|
/* for (i=0; i<nw; i++)
|
||
|
t[i]=0;*/
|
||
|
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);
|
||
|
}
|
||
|
i = (BN_num_bits(a) - n + (BN_BITS2 - 1)) / BN_BITS2;
|
||
|
if (r != a) {
|
||
|
r->neg = a->neg;
|
||
|
if (bn_wexpand(r, i) == 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 = 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;
|
||
|
}
|
||
|
bn_check_top(r);
|
||
|
return (1);
|
||
|
}
|