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76350fef1c
Add a library for common encryption/hashing algorithms. Currently implements MD4, MD5, SHA1, RC4 (all taken from advapi32 with minor modifications) and AES (taken from OpenWrt Linux). The library is currently used by advapi32 only, but ksecdd will make use of it later as well. svn path=/trunk/; revision=61805
67 lines
1.9 KiB
C
67 lines
1.9 KiB
C
/*
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* Copyright 2006 Mike McCormack
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*
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* based on arc4.cpp - written and placed in the public domain by Wei Dai
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
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*/
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/* http://cryptopp.sourceforge.net/docs/ref521/arc4_8cpp-source.html */
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#include "rc4.h"
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void rc4_init(RC4_CONTEXT *a4i, const unsigned char *key, unsigned int keyLen)
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{
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unsigned int keyIndex = 0, stateIndex = 0;
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unsigned int i, a;
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a4i->x = a4i->y = 0;
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for (i=0; i<256; i++)
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a4i->state[i] = i;
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for (i=0; i<256; i++)
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{
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a = a4i->state[i];
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stateIndex += key[keyIndex] + a;
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stateIndex &= 0xff;
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a4i->state[i] = a4i->state[stateIndex];
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a4i->state[stateIndex] = a;
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if (++keyIndex >= keyLen)
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keyIndex = 0;
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}
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}
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void rc4_crypt(RC4_CONTEXT *a4i, unsigned char *inoutString, unsigned int length)
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{
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unsigned char *const s=a4i->state;
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unsigned int x = a4i->x;
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unsigned int y = a4i->y;
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unsigned int a, b;
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while(length--)
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{
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x = (x+1) & 0xff;
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a = s[x];
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y = (y+a) & 0xff;
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b = s[y];
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s[x] = b;
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s[y] = a;
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*inoutString++ ^= s[(a+b) & 0xff];
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}
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a4i->x = x;
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a4i->y = y;
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}
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