1 /* crypto/rc2/rc2_cbc.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59 #include <openssl/rc2.h>
60 #include "rc2_locl.h"
61
62 void RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
63 RC2_KEY *ks, unsigned char *iv, int encrypt)
64 {
65 register unsigned long tin0,tin1;
66 register unsigned long tout0,tout1,xor0,xor1;
67 register long l=length;
68 unsigned long tin[2];
69
70 if (encrypt)
71 {
72 c2l(iv,tout0);
73 c2l(iv,tout1);
74 iv-=8;
75 for (l-=8; l>=0; l-=8)
76 {
77 c2l(in,tin0);
78 c2l(in,tin1);
79 tin0^=tout0;
80 tin1^=tout1;
81 tin[0]=tin0;
82 tin[1]=tin1;
83 RC2_encrypt(tin,ks);
84 tout0=tin[0]; l2c(tout0,out);
85 tout1=tin[1]; l2c(tout1,out);
86 }
87 if (l != -8)
88 {
89 c2ln(in,tin0,tin1,l+8);
90 tin0^=tout0;
91 tin1^=tout1;
92 tin[0]=tin0;
93 tin[1]=tin1;
94 RC2_encrypt(tin,ks);
95 tout0=tin[0]; l2c(tout0,out);
96 tout1=tin[1]; l2c(tout1,out);
97 }
98 l2c(tout0,iv);
99 l2c(tout1,iv);
100 }
101 else
102 {
103 c2l(iv,xor0);
104 c2l(iv,xor1);
105 iv-=8;
106 for (l-=8; l>=0; l-=8)
107 {
108 c2l(in,tin0); tin[0]=tin0;
109 c2l(in,tin1); tin[1]=tin1;
110 RC2_decrypt(tin,ks);
111 tout0=tin[0]^xor0;
112 tout1=tin[1]^xor1;
113 l2c(tout0,out);
114 l2c(tout1,out);
115 xor0=tin0;
116 xor1=tin1;
117 }
118 if (l != -8)
119 {
120 c2l(in,tin0); tin[0]=tin0;
121 c2l(in,tin1); tin[1]=tin1;
122 RC2_decrypt(tin,ks);
123 tout0=tin[0]^xor0;
124 tout1=tin[1]^xor1;
125 l2cn(tout0,tout1,out,l+8);
126 xor0=tin0;
127 xor1=tin1;
128 }
129 l2c(xor0,iv);
130 l2c(xor1,iv);
131 }
132 tin0=tin1=tout0=tout1=xor0=xor1=0;
133 tin[0]=tin[1]=0;
134 }
135
136 void RC2_encrypt(unsigned long *d, RC2_KEY *key)
137 {
138 int i,n;
139 register RC2_INT *p0,*p1;
140 register RC2_INT x0,x1,x2,x3,t;
141 unsigned long l;
142
143 l=d[0];
144 x0=(RC2_INT)l&0xffff;
145 x1=(RC2_INT)(l>>16L);
146 l=d[1];
147 x2=(RC2_INT)l&0xffff;
148 x3=(RC2_INT)(l>>16L);
149
150 n=3;
151 i=5;
152
153 p0=p1= &(key->data[0]);
154 for (;;)
155 {
156 t=(x0+(x1& ~x3)+(x2&x3)+ *(p0++))&0xffff;
157 x0=(t<<1)|(t>>15);
158 t=(x1+(x2& ~x0)+(x3&x0)+ *(p0++))&0xffff;
159 x1=(t<<2)|(t>>14);
160 t=(x2+(x3& ~x1)+(x0&x1)+ *(p0++))&0xffff;
161 x2=(t<<3)|(t>>13);
162 t=(x3+(x0& ~x2)+(x1&x2)+ *(p0++))&0xffff;
163 x3=(t<<5)|(t>>11);
164
165 if (--i == 0)
166 {
167 if (--n == 0) break;
168 i=(n == 2)?6:5;
169
170 x0+=p1[x3&0x3f];
171 x1+=p1[x0&0x3f];
172 x2+=p1[x1&0x3f];
173 x3+=p1[x2&0x3f];
174 }
175 }
176
177 d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
178 d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
179 }
180
181 void RC2_decrypt(unsigned long *d, RC2_KEY *key)
182 {
183 int i,n;
184 register RC2_INT *p0,*p1;
185 register RC2_INT x0,x1,x2,x3,t;
186 unsigned long l;
187
188 l=d[0];
189 x0=(RC2_INT)l&0xffff;
190 x1=(RC2_INT)(l>>16L);
191 l=d[1];
192 x2=(RC2_INT)l&0xffff;
193 x3=(RC2_INT)(l>>16L);
194
195 n=3;
196 i=5;
197
198 p0= &(key->data[63]);
199 p1= &(key->data[0]);
200 for (;;)
201 {
202 t=((x3<<11)|(x3>>5))&0xffff;
203 x3=(t-(x0& ~x2)-(x1&x2)- *(p0--))&0xffff;
204 t=((x2<<13)|(x2>>3))&0xffff;
205 x2=(t-(x3& ~x1)-(x0&x1)- *(p0--))&0xffff;
206 t=((x1<<14)|(x1>>2))&0xffff;
207 x1=(t-(x2& ~x0)-(x3&x0)- *(p0--))&0xffff;
208 t=((x0<<15)|(x0>>1))&0xffff;
209 x0=(t-(x1& ~x3)-(x2&x3)- *(p0--))&0xffff;
210
211 if (--i == 0)
212 {
213 if (--n == 0) break;
214 i=(n == 2)?6:5;
215
216 x3=(x3-p1[x2&0x3f])&0xffff;
217 x2=(x2-p1[x1&0x3f])&0xffff;
218 x1=(x1-p1[x0&0x3f])&0xffff;
219 x0=(x0-p1[x3&0x3f])&0xffff;
220 }
221 }
222
223 d[0]=(unsigned long)(x0&0xffff)|((unsigned long)(x1&0xffff)<<16L);
224 d[1]=(unsigned long)(x2&0xffff)|((unsigned long)(x3&0xffff)<<16L);
225 }