e_rc2.c revision 296465 
1/* crypto/evp/e_rc2.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 <stdio.h>
60#include "cryptlib.h"
61
62#ifndef OPENSSL_NO_RC2
63
64# include <openssl/evp.h>
65# include <openssl/objects.h>
66# include "evp_locl.h"
67# include <openssl/rc2.h>
68
69static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
70                        const unsigned char *iv, int enc);
71static int rc2_meth_to_magic(EVP_CIPHER_CTX *ctx);
72static int rc2_magic_to_meth(int i);
73static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
74static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
75static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr);
76
77typedef struct {
78    int key_bits;               /* effective key bits */
79    RC2_KEY ks;                 /* key schedule */
80} EVP_RC2_KEY;
81
82# define data(ctx)       ((EVP_RC2_KEY *)(ctx)->cipher_data)
83
84IMPLEMENT_BLOCK_CIPHER(rc2, ks, RC2, EVP_RC2_KEY, NID_rc2,
85                       8,
86                       RC2_KEY_LENGTH, 8, 64,
87                       EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
88                       rc2_init_key, NULL,
89                       rc2_set_asn1_type_and_iv, rc2_get_asn1_type_and_iv,
90                       rc2_ctrl)
91# define RC2_40_MAGIC    0xa0
92# define RC2_64_MAGIC    0x78
93# define RC2_128_MAGIC   0x3a
94static const EVP_CIPHER r2_64_cbc_cipher = {
95    NID_rc2_64_cbc,
96    8, 8 /* 64 bit */ , 8,
97    EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
98    rc2_init_key,
99    rc2_cbc_cipher,
100    NULL,
101    sizeof(EVP_RC2_KEY),
102    rc2_set_asn1_type_and_iv,
103    rc2_get_asn1_type_and_iv,
104    rc2_ctrl,
105    NULL
106};
107
108static const EVP_CIPHER r2_40_cbc_cipher = {
109    NID_rc2_40_cbc,
110    8, 5 /* 40 bit */ , 8,
111    EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
112    rc2_init_key,
113    rc2_cbc_cipher,
114    NULL,
115    sizeof(EVP_RC2_KEY),
116    rc2_set_asn1_type_and_iv,
117    rc2_get_asn1_type_and_iv,
118    rc2_ctrl,
119    NULL
120};
121
122const EVP_CIPHER *EVP_rc2_64_cbc(void)
123{
124    return (&r2_64_cbc_cipher);
125}
126
127const EVP_CIPHER *EVP_rc2_40_cbc(void)
128{
129    return (&r2_40_cbc_cipher);
130}
131
132static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
133                        const unsigned char *iv, int enc)
134{
135    RC2_set_key(&data(ctx)->ks, EVP_CIPHER_CTX_key_length(ctx),
136                key, data(ctx)->key_bits);
137    return 1;
138}
139
140static int rc2_meth_to_magic(EVP_CIPHER_CTX *e)
141{
142    int i;
143
144    EVP_CIPHER_CTX_ctrl(e, EVP_CTRL_GET_RC2_KEY_BITS, 0, &i);
145    if (i == 128)
146        return (RC2_128_MAGIC);
147    else if (i == 64)
148        return (RC2_64_MAGIC);
149    else if (i == 40)
150        return (RC2_40_MAGIC);
151    else
152        return (0);
153}
154
155static int rc2_magic_to_meth(int i)
156{
157    if (i == RC2_128_MAGIC)
158        return 128;
159    else if (i == RC2_64_MAGIC)
160        return 64;
161    else if (i == RC2_40_MAGIC)
162        return 40;
163    else {
164        EVPerr(EVP_F_RC2_MAGIC_TO_METH, EVP_R_UNSUPPORTED_KEY_SIZE);
165        return (0);
166    }
167}
168
169static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
170{
171    long num = 0;
172    int i = 0;
173    int key_bits;
174    unsigned int l;
175    unsigned char iv[EVP_MAX_IV_LENGTH];
176
177    if (type != NULL) {
178        l = EVP_CIPHER_CTX_iv_length(c);
179        OPENSSL_assert(l <= sizeof(iv));
180        i = ASN1_TYPE_get_int_octetstring(type, &num, iv, l);
181        if (i != (int)l)
182            return (-1);
183        key_bits = rc2_magic_to_meth((int)num);
184        if (!key_bits)
185            return (-1);
186        if (i > 0)
187            EVP_CipherInit_ex(c, NULL, NULL, NULL, iv, -1);
188        EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_RC2_KEY_BITS, key_bits, NULL);
189        EVP_CIPHER_CTX_set_key_length(c, key_bits / 8);
190    }
191    return (i);
192}
193
194static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
195{
196    long num;
197    int i = 0, j;
198
199    if (type != NULL) {
200        num = rc2_meth_to_magic(c);
201        j = EVP_CIPHER_CTX_iv_length(c);
202        i = ASN1_TYPE_set_int_octetstring(type, num, c->oiv, j);
203    }
204    return (i);
205}
206
207static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)
208{
209    switch (type) {
210    case EVP_CTRL_INIT:
211        data(c)->key_bits = EVP_CIPHER_CTX_key_length(c) * 8;
212        return 1;
213
214    case EVP_CTRL_GET_RC2_KEY_BITS:
215        *(int *)ptr = data(c)->key_bits;
216        return 1;
217
218    case EVP_CTRL_SET_RC2_KEY_BITS:
219        if (arg > 0) {
220            data(c)->key_bits = arg;
221            return 1;
222        }
223        return 0;
224
225    default:
226        return -1;
227    }
228}
229
230#endif
231