ReactOS  0.4.14-dev-49-gfb4591c
rc4.c
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1 /*
2  * Copyright 2006 Mike McCormack
3  *
4  * based on arc4.cpp - written and placed in the public domain by Wei Dai
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
19  */
20 
21 /* http://cryptopp.sourceforge.net/docs/ref521/arc4_8cpp-source.html */
22 
23 #include "rc4.h"
24 
25 void rc4_init(RC4_CONTEXT *a4i, const unsigned char *key, unsigned int keyLen)
26 {
27  unsigned int keyIndex = 0, stateIndex = 0;
28  unsigned int i, a;
29 
30  a4i->x = a4i->y = 0;
31 
32  for (i=0; i<256; i++)
33  a4i->state[i] = i;
34 
35  for (i=0; i<256; i++)
36  {
37  a = a4i->state[i];
38  stateIndex += key[keyIndex] + a;
39  stateIndex &= 0xff;
40  a4i->state[i] = a4i->state[stateIndex];
41  a4i->state[stateIndex] = a;
42  if (++keyIndex >= keyLen)
43  keyIndex = 0;
44  }
45 }
46 
47 void rc4_crypt(RC4_CONTEXT *a4i, unsigned char *inoutString, unsigned int length)
48 {
49  unsigned char *const s=a4i->state;
50  unsigned int x = a4i->x;
51  unsigned int y = a4i->y;
52  unsigned int a, b;
53 
54  while(length--)
55  {
56  x = (x+1) & 0xff;
57  a = s[x];
58  y = (y+a) & 0xff;
59  b = s[y];
60  s[x] = b;
61  s[y] = a;
62  *inoutString++ ^= s[(a+b) & 0xff];
63  }
64 
65  a4i->x = x;
66  a4i->y = y;
67 }
GLint GLint GLint GLint GLint x
Definition: gl.h:1548
GLsizei GLenum const GLvoid GLsizei GLenum GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLint GLint GLint GLshort GLshort GLshort GLubyte GLubyte GLubyte GLuint GLuint GLuint GLushort GLushort GLushort GLbyte GLbyte GLbyte GLbyte GLdouble GLdouble GLdouble GLdouble GLfloat GLfloat GLfloat GLfloat GLint GLint GLint GLint GLshort GLshort GLshort GLshort GLubyte GLubyte GLubyte GLubyte GLuint GLuint GLuint GLuint GLushort GLushort GLushort GLushort GLboolean const GLdouble const GLfloat const GLint const GLshort const GLbyte const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLdouble const GLfloat const GLfloat const GLint const GLint const GLshort const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort const GLdouble const GLfloat const GLint const GLshort GLenum GLenum GLenum GLfloat GLenum GLint GLenum GLenum GLenum GLfloat GLenum GLenum GLint GLenum GLfloat GLenum GLint GLint GLushort GLenum GLenum GLfloat GLenum GLenum GLint GLfloat const GLubyte GLenum GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLint GLint GLsizei GLsizei GLint GLenum GLenum const GLvoid GLenum GLenum const GLfloat GLenum GLenum const GLint GLenum GLenum const GLdouble GLenum GLenum const GLfloat GLenum GLenum const GLint GLsizei GLuint GLfloat GLuint GLbitfield GLfloat GLint GLuint GLboolean GLenum GLfloat GLenum GLbitfield GLenum GLfloat GLfloat GLint GLint const GLfloat GLenum GLfloat GLfloat GLint GLint GLfloat GLfloat GLint GLint const GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat GLint GLfloat GLfloat const GLdouble const GLfloat const GLdouble const GLfloat GLint i
Definition: glfuncs.h:248
#define a
Definition: ke_i.h:78
unsigned char x
Definition: rc4.h:7
#define b
Definition: ke_i.h:79
void rc4_crypt(RC4_CONTEXT *a4i, unsigned char *inoutString, unsigned int length)
Definition: rc4.c:47
GLboolean GLboolean GLboolean b
Definition: glext.h:6204
unsigned char state[256]
Definition: rc4.h:6
GLenum GLuint GLenum GLsizei length
Definition: glext.h:5579
#define for
Definition: utility.h:88
GLdouble s
Definition: gl.h:2039
unsigned char y
Definition: rc4.h:7
GLint GLint GLint GLint GLint GLint y
Definition: gl.h:1548
void rc4_init(RC4_CONTEXT *a4i, const unsigned char *key, unsigned int keyLen)
Definition: rc4.c:25
GLboolean GLboolean GLboolean GLboolean a
Definition: glext.h:6204
Definition: path.c:42