xref: /freebsd/crypto/openssl/crypto/evp/e_rc2.c (revision 8aac90f18aef7c9eea906c3ff9a001ca7b94f375)
1 /*
2  * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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 /*
11  * RC2 low level APIs are deprecated for public use, but still ok for internal
12  * use.
13  */
14 #include "internal/deprecated.h"
15 
16 #include <stdio.h>
17 #include "internal/cryptlib.h"
18 
19 #ifndef OPENSSL_NO_RC2
20 
21 # include <openssl/evp.h>
22 # include <openssl/objects.h>
23 # include "crypto/evp.h"
24 # include <openssl/rc2.h>
25 # include "evp_local.h"
26 
27 static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
28                         const unsigned char *iv, int enc);
29 static int rc2_meth_to_magic(EVP_CIPHER_CTX *ctx);
30 static int rc2_magic_to_meth(int i);
31 static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
32 static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type);
33 static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr);
34 
35 typedef struct {
36     int key_bits;               /* effective key bits */
37     RC2_KEY ks;                 /* key schedule */
38 } EVP_RC2_KEY;
39 
40 # define data(ctx)       EVP_C_DATA(EVP_RC2_KEY,ctx)
41 
42 IMPLEMENT_BLOCK_CIPHER(rc2, ks, RC2, EVP_RC2_KEY, NID_rc2,
43                        8,
44                        RC2_KEY_LENGTH, 8, 64,
45                        EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
46                        rc2_init_key, NULL,
47                        rc2_set_asn1_type_and_iv, rc2_get_asn1_type_and_iv,
48                        rc2_ctrl)
49 # define RC2_40_MAGIC    0xa0
50 # define RC2_64_MAGIC    0x78
51 # define RC2_128_MAGIC   0x3a
52 static const EVP_CIPHER r2_64_cbc_cipher = {
53     NID_rc2_64_cbc,
54     8, 8 /* 64 bit */ , 8,
55     EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
56     EVP_ORIG_GLOBAL,
57     rc2_init_key,
58     rc2_cbc_cipher,
59     NULL,
60     sizeof(EVP_RC2_KEY),
61     rc2_set_asn1_type_and_iv,
62     rc2_get_asn1_type_and_iv,
63     rc2_ctrl,
64     NULL
65 };
66 
67 static const EVP_CIPHER r2_40_cbc_cipher = {
68     NID_rc2_40_cbc,
69     8, 5 /* 40 bit */ , 8,
70     EVP_CIPH_CBC_MODE | EVP_CIPH_VARIABLE_LENGTH | EVP_CIPH_CTRL_INIT,
71     EVP_ORIG_GLOBAL,
72     rc2_init_key,
73     rc2_cbc_cipher,
74     NULL,
75     sizeof(EVP_RC2_KEY),
76     rc2_set_asn1_type_and_iv,
77     rc2_get_asn1_type_and_iv,
78     rc2_ctrl,
79     NULL
80 };
81 
82 const EVP_CIPHER *EVP_rc2_64_cbc(void)
83 {
84     return &r2_64_cbc_cipher;
85 }
86 
87 const EVP_CIPHER *EVP_rc2_40_cbc(void)
88 {
89     return &r2_40_cbc_cipher;
90 }
91 
92 static int rc2_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
93                         const unsigned char *iv, int enc)
94 {
95     RC2_set_key(&data(ctx)->ks, EVP_CIPHER_CTX_get_key_length(ctx),
96                 key, data(ctx)->key_bits);
97     return 1;
98 }
99 
100 static int rc2_meth_to_magic(EVP_CIPHER_CTX *e)
101 {
102     int i;
103 
104     if (EVP_CIPHER_CTX_ctrl(e, EVP_CTRL_GET_RC2_KEY_BITS, 0, &i) <= 0)
105         return 0;
106     if (i == 128)
107         return RC2_128_MAGIC;
108     else if (i == 64)
109         return RC2_64_MAGIC;
110     else if (i == 40)
111         return RC2_40_MAGIC;
112     else
113         return 0;
114 }
115 
116 static int rc2_magic_to_meth(int i)
117 {
118     if (i == RC2_128_MAGIC)
119         return 128;
120     else if (i == RC2_64_MAGIC)
121         return 64;
122     else if (i == RC2_40_MAGIC)
123         return 40;
124     else {
125         ERR_raise(ERR_LIB_EVP, EVP_R_UNSUPPORTED_KEY_SIZE);
126         return 0;
127     }
128 }
129 
130 static int rc2_get_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
131 {
132     long num = 0;
133     int i = 0;
134     int key_bits;
135     unsigned int l;
136     unsigned char iv[EVP_MAX_IV_LENGTH];
137 
138     if (type != NULL) {
139         l = EVP_CIPHER_CTX_get_iv_length(c);
140         OPENSSL_assert(l <= sizeof(iv));
141         i = ASN1_TYPE_get_int_octetstring(type, &num, iv, l);
142         if (i != (int)l)
143             return -1;
144         key_bits = rc2_magic_to_meth((int)num);
145         if (!key_bits)
146             return -1;
147         if (i > 0 && !EVP_CipherInit_ex(c, NULL, NULL, NULL, iv, -1))
148             return -1;
149         if (EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_RC2_KEY_BITS, key_bits,
150                                 NULL) <= 0
151                 || EVP_CIPHER_CTX_set_key_length(c, key_bits / 8) <= 0)
152             return -1;
153     }
154     return i;
155 }
156 
157 static int rc2_set_asn1_type_and_iv(EVP_CIPHER_CTX *c, ASN1_TYPE *type)
158 {
159     long num;
160     int i = 0, j;
161 
162     if (type != NULL) {
163         num = rc2_meth_to_magic(c);
164         j = EVP_CIPHER_CTX_get_iv_length(c);
165         i = ASN1_TYPE_set_int_octetstring(type, num, c->oiv, j);
166     }
167     return i;
168 }
169 
170 static int rc2_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)
171 {
172     switch (type) {
173     case EVP_CTRL_INIT:
174         data(c)->key_bits = EVP_CIPHER_CTX_get_key_length(c) * 8;
175         return 1;
176 
177     case EVP_CTRL_GET_RC2_KEY_BITS:
178         *(int *)ptr = data(c)->key_bits;
179         return 1;
180 
181     case EVP_CTRL_SET_RC2_KEY_BITS:
182         if (arg > 0) {
183             data(c)->key_bits = arg;
184             return 1;
185         }
186         return 0;
187 # ifdef PBE_PRF_TEST
188     case EVP_CTRL_PBE_PRF_NID:
189         *(int *)ptr = NID_hmacWithMD5;
190         return 1;
191 # endif
192 
193     default:
194         return -1;
195     }
196 }
197 
198 #endif
199