Import of old SSLeay release: SSLeay 0.9.1b (unreleased)
[openssl.git] / crypto / cast / c_enc.c
1 /* crypto/cast/c_enc.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 "cast.h"
60 #include "cast_lcl.h"
61
62 void CAST_encrypt(data,key)
63 CAST_LONG *data;
64 CAST_KEY *key;
65         {
66         register CAST_LONG l,r,*k,t;
67
68         k= &(key->data[0]);
69         l=data[0];
70         r=data[1];
71
72         E_CAST( 0,k,l,r,+,^,-);
73         E_CAST( 1,k,r,l,^,-,+);
74         E_CAST( 2,k,l,r,-,+,^);
75         E_CAST( 3,k,r,l,+,^,-);
76         E_CAST( 4,k,l,r,^,-,+);
77         E_CAST( 5,k,r,l,-,+,^);
78         E_CAST( 6,k,l,r,+,^,-);
79         E_CAST( 7,k,r,l,^,-,+);
80         E_CAST( 8,k,l,r,-,+,^);
81         E_CAST( 9,k,r,l,+,^,-);
82         E_CAST(10,k,l,r,^,-,+);
83         E_CAST(11,k,r,l,-,+,^);
84         E_CAST(12,k,l,r,+,^,-);
85         E_CAST(13,k,r,l,^,-,+);
86         E_CAST(14,k,l,r,-,+,^);
87         E_CAST(15,k,r,l,+,^,-);
88
89         data[1]=l&0xffffffffL;
90         data[0]=r&0xffffffffL;
91         }
92
93 void CAST_decrypt(data,key)
94 CAST_LONG *data;
95 CAST_KEY *key;
96         {
97         register CAST_LONG l,r,*k,t;
98
99         k= &(key->data[0]);
100         l=data[0];
101         r=data[1];
102
103         E_CAST(15,k,l,r,+,^,-);
104         E_CAST(14,k,r,l,-,+,^);
105         E_CAST(13,k,l,r,^,-,+);
106         E_CAST(12,k,r,l,+,^,-);
107         E_CAST(11,k,l,r,-,+,^);
108         E_CAST(10,k,r,l,^,-,+);
109         E_CAST( 9,k,l,r,+,^,-);
110         E_CAST( 8,k,r,l,-,+,^);
111         E_CAST( 7,k,l,r,^,-,+);
112         E_CAST( 6,k,r,l,+,^,-);
113         E_CAST( 5,k,l,r,-,+,^);
114         E_CAST( 4,k,r,l,^,-,+);
115         E_CAST( 3,k,l,r,+,^,-);
116         E_CAST( 2,k,r,l,-,+,^);
117         E_CAST( 1,k,l,r,^,-,+);
118         E_CAST( 0,k,r,l,+,^,-);
119
120         data[1]=l&0xffffffffL;
121         data[0]=r&0xffffffffL;
122         }
123
124 void CAST_cbc_encrypt(in, out, length, ks, iv, encrypt)
125 unsigned char *in;
126 unsigned char *out;
127 long length;
128 CAST_KEY *ks;
129 unsigned char *iv;
130 int encrypt;
131         {
132         register CAST_LONG tin0,tin1;
133         register CAST_LONG tout0,tout1,xor0,xor1;
134         register long l=length;
135         CAST_LONG tin[2];
136
137         if (encrypt)
138                 {
139                 n2l(iv,tout0);
140                 n2l(iv,tout1);
141                 iv-=8;
142                 for (l-=8; l>=0; l-=8)
143                         {
144                         n2l(in,tin0);
145                         n2l(in,tin1);
146                         tin0^=tout0;
147                         tin1^=tout1;
148                         tin[0]=tin0;
149                         tin[1]=tin1;
150                         CAST_encrypt(tin,ks);
151                         tout0=tin[0];
152                         tout1=tin[1];
153                         l2n(tout0,out);
154                         l2n(tout1,out);
155                         }
156                 if (l != -8)
157                         {
158                         n2ln(in,tin0,tin1,l+8);
159                         tin0^=tout0;
160                         tin1^=tout1;
161                         tin[0]=tin0;
162                         tin[1]=tin1;
163                         CAST_encrypt(tin,ks);
164                         tout0=tin[0];
165                         tout1=tin[1];
166                         l2n(tout0,out);
167                         l2n(tout1,out);
168                         }
169                 l2n(tout0,iv);
170                 l2n(tout1,iv);
171                 }
172         else
173                 {
174                 n2l(iv,xor0);
175                 n2l(iv,xor1);
176                 iv-=8;
177                 for (l-=8; l>=0; l-=8)
178                         {
179                         n2l(in,tin0);
180                         n2l(in,tin1);
181                         tin[0]=tin0;
182                         tin[1]=tin1;
183                         CAST_decrypt(tin,ks);
184                         tout0=tin[0]^xor0;
185                         tout1=tin[1]^xor1;
186                         l2n(tout0,out);
187                         l2n(tout1,out);
188                         xor0=tin0;
189                         xor1=tin1;
190                         }
191                 if (l != -8)
192                         {
193                         n2l(in,tin0);
194                         n2l(in,tin1);
195                         tin[0]=tin0;
196                         tin[1]=tin1;
197                         CAST_decrypt(tin,ks);
198                         tout0=tin[0]^xor0;
199                         tout1=tin[1]^xor1;
200                         l2nn(tout0,tout1,out,l+8);
201                         xor0=tin0;
202                         xor1=tin1;
203                         }
204                 l2n(xor0,iv);
205                 l2n(xor1,iv);
206                 }
207         tin0=tin1=tout0=tout1=xor0=xor1=0;
208         tin[0]=tin[1]=0;
209         }
210