xref: /freebsd/crypto/openssl/crypto/evp/e_rc2.c (revision d9a42747950146bf03cda7f6e25d219253f8a57a)
1 /*
2  * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL license (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 #include <stdio.h>
11 #include "internal/cryptlib.h"
12 
13 #ifndef OPENSSL_NO_RC2
14 
15 # include <openssl/evp.h>
16 # include <openssl/objects.h>
17 # include "crypto/evp.h"
18 # include <openssl/rc2.h>
19 
20 static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
21                         const unsigned char *iv, int enc);
22 static int rc2_meth_to_magic(EVP_CIPHER_CTX *ctx);
23 static int rc2_magic_to_meth(int i);
24 static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
25 static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
26 static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr);
27 
28 typedef struct {
29     int key_bits;               /* effective key bits */
30     RC2_KEY ks;                 /* key schedule */
31 } EVP_RC2_KEY;
32 
33 # define data(ctx)       EVP_C_DATA(EVP_RC2_KEY,ctx)
34 
35 IMPLEMENT_BLOCK_CIPHER(rc2, ks, RC2, EVP_RC2_KEY, NID_rc2,
36                        8,
37                        RC2_KEY_LENGTH, 8, 64,
38                        EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
39                        rc2_init_key, NULL,
40                        rc2_set_asn1_type_and_iv, rc2_get_asn1_type_and_iv,
41                        rc2_ctrl)
42 # define RC2_40_MAGIC    0xa0
43 # define RC2_64_MAGIC    0x78
44 # define RC2_128_MAGIC   0x3a
45 static const EVP_CIPHER r2_64_cbc_cipher = {
46     NID_rc2_64_cbc,
47     8, 8 /* 64 bit */ , 8,
48     EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
49     rc2_init_key,
50     rc2_cbc_cipher,
51     NULL,
52     sizeof(EVP_RC2_KEY),
53     rc2_set_asn1_type_and_iv,
54     rc2_get_asn1_type_and_iv,
55     rc2_ctrl,
56     NULL
57 };
58 
59 static const EVP_CIPHER r2_40_cbc_cipher = {
60     NID_rc2_40_cbc,
61     8, 5 /* 40 bit */ , 8,
62     EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
63     rc2_init_key,
64     rc2_cbc_cipher,
65     NULL,
66     sizeof(EVP_RC2_KEY),
67     rc2_set_asn1_type_and_iv,
68     rc2_get_asn1_type_and_iv,
69     rc2_ctrl,
70     NULL
71 };
72 
73 const EVP_CIPHER *EVP_rc2_64_cbc(void)
74 {
75     return &r2_64_cbc_cipher;
76 }
77 
78 const EVP_CIPHER *EVP_rc2_40_cbc(void)
79 {
80     return &r2_40_cbc_cipher;
81 }
82 
83 static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
84                         const unsigned char *iv, int enc)
85 {
86     RC2_set_key(&data(ctx)->ks, EVP_CIPHER_CTX_key_length(ctx),
87                 key, data(ctx)->key_bits);
88     return 1;
89 }
90 
91 static int rc2_meth_to_magic(EVP_CIPHER_CTX *e)
92 {
93     int i;
94 
95     if (EVP_CIPHER_CTX_ctrl(e, EVP_CTRL_GET_RC2_KEY_BITS, 0, &i) <= 0)
96         return 0;
97     if (i == 128)
98         return RC2_128_MAGIC;
99     else if (i == 64)
100         return RC2_64_MAGIC;
101     else if (i == 40)
102         return RC2_40_MAGIC;
103     else
104         return 0;
105 }
106 
107 static int rc2_magic_to_meth(int i)
108 {
109     if (i == RC2_128_MAGIC)
110         return 128;
111     else if (i == RC2_64_MAGIC)
112         return 64;
113     else if (i == RC2_40_MAGIC)
114         return 40;
115     else {
116         EVPerr(EVP_F_RC2_MAGIC_TO_METH, EVP_R_UNSUPPORTED_KEY_SIZE);
117         return 0;
118     }
119 }
120 
121 static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
122 {
123     long num = 0;
124     int i = 0;
125     int key_bits;
126     unsigned int l;
127     unsigned char iv[EVP_MAX_IV_LENGTH];
128 
129     if (type != NULL) {
130         l = EVP_CIPHER_CTX_iv_length(c);
131         OPENSSL_assert(l <= sizeof(iv));
132         i = ASN1_TYPE_get_int_octetstring(type, &num, iv, l);
133         if (i != (int)l)
134             return -1;
135         key_bits = rc2_magic_to_meth((int)num);
136         if (!key_bits)
137             return -1;
138         if (i > 0 && !EVP_CipherInit_ex(c, NULL, NULL, NULL, iv, -1))
139             return -1;
140         if (EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_RC2_KEY_BITS, key_bits,
141                                 NULL) <= 0
142                 || EVP_CIPHER_CTX_set_key_length(c, key_bits / 8) <= 0)
143             return -1;
144     }
145     return i;
146 }
147 
148 static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
149 {
150     long num;
151     int i = 0, j;
152 
153     if (type != NULL) {
154         num = rc2_meth_to_magic(c);
155         j = EVP_CIPHER_CTX_iv_length(c);
156         i = ASN1_TYPE_set_int_octetstring(type, num,
157                                           (unsigned char *)EVP_CIPHER_CTX_original_iv(c),
158                                           j);
159     }
160     return i;
161 }
162 
163 static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)
164 {
165     switch (type) {
166     case EVP_CTRL_INIT:
167         data(c)->key_bits = EVP_CIPHER_CTX_key_length(c) * 8;
168         return 1;
169 
170     case EVP_CTRL_GET_RC2_KEY_BITS:
171         *(int *)ptr = data(c)->key_bits;
172         return 1;
173 
174     case EVP_CTRL_SET_RC2_KEY_BITS:
175         if (arg > 0) {
176             data(c)->key_bits = arg;
177             return 1;
178         }
179         return 0;
180 # ifdef PBE_PRF_TEST
181     case EVP_CTRL_PBE_PRF_NID:
182         *(int *)ptr = NID_hmacWithMD5;
183         return 1;
184 # endif
185 
186     default:
187         return -1;
188     }
189 }
190 
191 #endif
192