ReactOS 0.4.15-dev-8127-g6338913
rc2.c
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1/*
2 * dlls/rsaen/rc2.c
3 * RC2 functions
4 *
5 * Copyright 2004 Michael Jung
6 * Based on public domain code by Tom St Denis (tomstdenis@iahu.ca)
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
21 */
22
23/*
24 * This file contains code from the LibTomCrypt cryptographic
25 * library written by Tom St Denis (tomstdenis@iahu.ca). LibTomCrypt
26 * is in the public domain. The code in this file is tailored to
27 * special requirements. Take a look at http://libtomcrypt.org for the
28 * original version.
29 */
30
31#include "tomcrypt.h"
32
33/* 256-entry permutation table, probably derived somehow from pi */
34static const unsigned char permute[256] = {
35 217,120,249,196, 25,221,181,237, 40,233,253,121, 74,160,216,157,
36 198,126, 55,131, 43,118, 83,142, 98, 76,100,136, 68,139,251,162,
37 23,154, 89,245,135,179, 79, 19, 97, 69,109,141, 9,129,125, 50,
38 189,143, 64,235,134,183,123, 11,240,149, 33, 34, 92,107, 78,130,
39 84,214,101,147,206, 96,178, 28,115, 86,192, 20,167,140,241,220,
40 18,117,202, 31, 59,190,228,209, 66, 61,212, 48,163, 60,182, 38,
41 111,191, 14,218, 70,105, 7, 87, 39,242, 29,155,188,148, 67, 3,
42 248, 17,199,246,144,239, 62,231, 6,195,213, 47,200,102, 30,215,
43 8,232,234,222,128, 82,238,247,132,170,114,172, 53, 77,106, 42,
44 150, 26,210,113, 90, 21, 73,116, 75,159,208, 94, 4, 24,164,236,
45 194,224, 65,110, 15, 81,203,204, 36,145,175, 80,161,244,112, 57,
46 153,124, 58,133, 35,184,180,122,252, 2, 54, 91, 37, 85,151, 49,
47 45, 93,250,152,227,138,146,174, 5,223, 41, 16,103,108,186,201,
48 211, 0,230,207,225,158,168, 44, 99, 22, 1, 63, 88,226,137,169,
49 13, 56, 52, 27,171, 51,255,176,187, 72, 12, 95,185,177,205, 46,
50 197,243,219, 71,229,165,156,119, 10,166, 32,104,254,127,193,173
51};
52
53int rc2_setup(const unsigned char *key, int keylen, int bits, int rounds, rc2_key *rc2)
54{
55 unsigned *xkey = rc2->xkey;
56 unsigned char tmp[128];
57 unsigned T8, TM;
58 int i;
59
60 if (keylen < 5 || keylen > 128) {
62 }
63
64 if (rounds != 0 && rounds != 16) {
66 }
67
68 /* Following comment is from Eric Young's rc2 code: */
69 /* It has come to my attention that there are 2 versions of the RC2
70 * key schedule. One which is normal, and anther which has a hook to
71 * use a reduced key length.
72 * BSAFE uses the 'retarded' version. What I previously shipped is
73 * the same as specifying 1024 for the 'bits' parameter. BSAFE uses
74 * a version where the bits parameter is the same as len*8 */
75 /* Seems like MS uses the 'retarded' version, too.
76 * Adjust effective keylen bits */
77 if (bits <= 0) bits = keylen << 3;
78 if (bits > 1024) bits = 1024;
79
80 for (i = 0; i < keylen; i++) {
81 tmp[i] = key[i] & 255;
82 }
83
84 /* Phase 1: Expand input key to 128 bytes */
85 if (keylen < 128) {
86 for (i = keylen; i < 128; i++) {
87 tmp[i] = permute[(tmp[i - 1] + tmp[i - keylen]) & 255];
88 }
89 }
90
91 /* Phase 2 - reduce effective key size to "bits" */
92 /*bits = keylen<<3; */
93 T8 = (unsigned)(bits+7)>>3;
94 TM = (255 >> (unsigned)(7 & -bits));
95 tmp[128 - T8] = permute[tmp[128 - T8] & TM];
96 for (i = 127 - T8; i >= 0; i--) {
97 tmp[i] = permute[tmp[i + 1] ^ tmp[i + T8]];
98 }
99
100 /* Phase 3 - copy to xkey in little-endian order */
101 for (i = 0; i < 64; i++) {
102 xkey[i] = (unsigned)tmp[2*i] + ((unsigned)tmp[2*i+1] << 8);
103 }
104
105 return CRYPT_OK;
106}
107
108/**********************************************************************\
109* Encrypt an 8-byte block of plaintext using the given key. *
110\**********************************************************************/
111void rc2_ecb_encrypt( const unsigned char *plain,
112 unsigned char *cipher,
113 rc2_key *rc2)
114{
115 unsigned *xkey;
116 unsigned x76, x54, x32, x10, i;
117
118 xkey = rc2->xkey;
119
120 x76 = ((unsigned)plain[7] << 8) + (unsigned)plain[6];
121 x54 = ((unsigned)plain[5] << 8) + (unsigned)plain[4];
122 x32 = ((unsigned)plain[3] << 8) + (unsigned)plain[2];
123 x10 = ((unsigned)plain[1] << 8) + (unsigned)plain[0];
124
125 for (i = 0; i < 16; i++) {
126 x10 = (x10 + (x32 & ~x76) + (x54 & x76) + xkey[4*i+0]) & 0xFFFF;
127 x10 = ((x10 << 1) | (x10 >> 15));
128
129 x32 = (x32 + (x54 & ~x10) + (x76 & x10) + xkey[4*i+1]) & 0xFFFF;
130 x32 = ((x32 << 2) | (x32 >> 14));
131
132 x54 = (x54 + (x76 & ~x32) + (x10 & x32) + xkey[4*i+2]) & 0xFFFF;
133 x54 = ((x54 << 3) | (x54 >> 13));
134
135 x76 = (x76 + (x10 & ~x54) + (x32 & x54) + xkey[4*i+3]) & 0xFFFF;
136 x76 = ((x76 << 5) | (x76 >> 11));
137
138 if (i == 4 || i == 10) {
139 x10 = (x10 + xkey[x76 & 63]) & 0xFFFF;
140 x32 = (x32 + xkey[x10 & 63]) & 0xFFFF;
141 x54 = (x54 + xkey[x32 & 63]) & 0xFFFF;
142 x76 = (x76 + xkey[x54 & 63]) & 0xFFFF;
143 }
144 }
145
146 cipher[0] = (unsigned char)x10;
147 cipher[1] = (unsigned char)(x10 >> 8);
148 cipher[2] = (unsigned char)x32;
149 cipher[3] = (unsigned char)(x32 >> 8);
150 cipher[4] = (unsigned char)x54;
151 cipher[5] = (unsigned char)(x54 >> 8);
152 cipher[6] = (unsigned char)x76;
153 cipher[7] = (unsigned char)(x76 >> 8);
154}
155
156/**********************************************************************\
157* Decrypt an 8-byte block of ciphertext using the given key. *
158\**********************************************************************/
159void rc2_ecb_decrypt( const unsigned char *cipher,
160 unsigned char *plain,
161 rc2_key *rc2)
162{
163 unsigned x76, x54, x32, x10;
164 unsigned *xkey;
165 int i;
166
167 xkey = rc2->xkey;
168
169 x76 = ((unsigned)cipher[7] << 8) + (unsigned)cipher[6];
170 x54 = ((unsigned)cipher[5] << 8) + (unsigned)cipher[4];
171 x32 = ((unsigned)cipher[3] << 8) + (unsigned)cipher[2];
172 x10 = ((unsigned)cipher[1] << 8) + (unsigned)cipher[0];
173
174 for (i = 15; i >= 0; i--) {
175 if (i == 4 || i == 10) {
176 x76 = (x76 - xkey[x54 & 63]) & 0xFFFF;
177 x54 = (x54 - xkey[x32 & 63]) & 0xFFFF;
178 x32 = (x32 - xkey[x10 & 63]) & 0xFFFF;
179 x10 = (x10 - xkey[x76 & 63]) & 0xFFFF;
180 }
181
182 x76 = ((x76 << 11) | (x76 >> 5));
183 x76 = (x76 - ((x10 & ~x54) + (x32 & x54) + xkey[4*i+3])) & 0xFFFF;
184
185 x54 = ((x54 << 13) | (x54 >> 3));
186 x54 = (x54 - ((x76 & ~x32) + (x10 & x32) + xkey[4*i+2])) & 0xFFFF;
187
188 x32 = ((x32 << 14) | (x32 >> 2));
189 x32 = (x32 - ((x54 & ~x10) + (x76 & x10) + xkey[4*i+1])) & 0xFFFF;
190
191 x10 = ((x10 << 15) | (x10 >> 1));
192 x10 = (x10 - ((x32 & ~x76) + (x54 & x76) + xkey[4*i+0])) & 0xFFFF;
193 }
194
195 plain[0] = (unsigned char)x10;
196 plain[1] = (unsigned char)(x10 >> 8);
197 plain[2] = (unsigned char)x32;
198 plain[3] = (unsigned char)(x32 >> 8);
199 plain[4] = (unsigned char)x54;
200 plain[5] = (unsigned char)(x54 >> 8);
201 plain[6] = (unsigned char)x76;
202 plain[7] = (unsigned char)(x76 >> 8);
203}
static const WCHAR rc2[]
Definition: oid.c:1216
@ CRYPT_INVALID_ROUNDS
Definition: tomcrypt.h:48
@ CRYPT_INVALID_KEYSIZE
Definition: tomcrypt.h:47
@ CRYPT_OK
Definition: tomcrypt.h:43
unsigned char
Definition: typeof.h:29
GLenum GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * bits
Definition: glext.h:10929
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
static DATA_BLOB cipher
Definition: protectdata.c:38
static unsigned(__cdecl *hash_bstr)(bstr_t s)
void rc2_ecb_encrypt(const unsigned char *plain, unsigned char *cipher, rc2_key *rc2)
Definition: rc2.c:111
static const unsigned char permute[256]
Definition: rc2.c:34
int rc2_setup(const unsigned char *key, int keylen, int bits, int rounds, rc2_key *rc2)
Definition: rc2.c:53
void rc2_ecb_decrypt(const unsigned char *cipher, unsigned char *plain, rc2_key *rc2)
Definition: rc2.c:159
Definition: copy.c:22