[CRYPTO] all: Pass tfm instead of ctx to algorithms
[linux-2.6.git] / crypto / crypto_null.c
1 /* 
2  * Cryptographic API.
3  *
4  * Null algorithms, aka Much Ado About Nothing.
5  *
6  * These are needed for IPsec, and may be useful in general for
7  * testing & debugging.
8  * 
9  * The null cipher is compliant with RFC2410.
10  *
11  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  */
19 #include <linux/init.h>
20 #include <linux/module.h>
21 #include <linux/mm.h>
22 #include <asm/scatterlist.h>
23 #include <linux/crypto.h>
24 #include <linux/string.h>
25
26 #define NULL_KEY_SIZE           0
27 #define NULL_BLOCK_SIZE         1
28 #define NULL_DIGEST_SIZE        0
29
30 static int null_compress(struct crypto_tfm *tfm, const u8 *src,
31                          unsigned int slen, u8 *dst, unsigned int *dlen)
32 {
33         if (slen > *dlen)
34                 return -EINVAL;
35         memcpy(dst, src, slen);
36         *dlen = slen;
37         return 0;
38 }
39
40 static void null_init(struct crypto_tfm *tfm)
41 { }
42
43 static void null_update(struct crypto_tfm *tfm, const u8 *data,
44                         unsigned int len)
45 { }
46
47 static void null_final(struct crypto_tfm *tfm, u8 *out)
48 { }
49
50 static int null_setkey(struct crypto_tfm *tfm, const u8 *key,
51                        unsigned int keylen, u32 *flags)
52 { return 0; }
53
54 static void null_crypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
55 {
56         memcpy(dst, src, NULL_BLOCK_SIZE);
57 }
58
59 static struct crypto_alg compress_null = {
60         .cra_name               =       "compress_null",
61         .cra_flags              =       CRYPTO_ALG_TYPE_COMPRESS,
62         .cra_blocksize          =       NULL_BLOCK_SIZE,
63         .cra_ctxsize            =       0,
64         .cra_module             =       THIS_MODULE,
65         .cra_list               =       LIST_HEAD_INIT(compress_null.cra_list),
66         .cra_u                  =       { .compress = {
67         .coa_compress           =       null_compress,
68         .coa_decompress         =       null_compress } }
69 };
70
71 static struct crypto_alg digest_null = {
72         .cra_name               =       "digest_null",
73         .cra_flags              =       CRYPTO_ALG_TYPE_DIGEST,
74         .cra_blocksize          =       NULL_BLOCK_SIZE,
75         .cra_ctxsize            =       0,
76         .cra_module             =       THIS_MODULE,
77         .cra_list               =       LIST_HEAD_INIT(digest_null.cra_list),   
78         .cra_u                  =       { .digest = {
79         .dia_digestsize         =       NULL_DIGEST_SIZE,
80         .dia_init               =       null_init,
81         .dia_update             =       null_update,
82         .dia_final              =       null_final } }
83 };
84
85 static struct crypto_alg cipher_null = {
86         .cra_name               =       "cipher_null",
87         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
88         .cra_blocksize          =       NULL_BLOCK_SIZE,
89         .cra_ctxsize            =       0,
90         .cra_module             =       THIS_MODULE,
91         .cra_list               =       LIST_HEAD_INIT(cipher_null.cra_list),
92         .cra_u                  =       { .cipher = {
93         .cia_min_keysize        =       NULL_KEY_SIZE,
94         .cia_max_keysize        =       NULL_KEY_SIZE,
95         .cia_setkey             =       null_setkey,
96         .cia_encrypt            =       null_crypt,
97         .cia_decrypt            =       null_crypt } }
98 };
99
100 MODULE_ALIAS("compress_null");
101 MODULE_ALIAS("digest_null");
102 MODULE_ALIAS("cipher_null");
103
104 static int __init init(void)
105 {
106         int ret = 0;
107         
108         ret = crypto_register_alg(&cipher_null);
109         if (ret < 0)
110                 goto out;
111
112         ret = crypto_register_alg(&digest_null);
113         if (ret < 0) {
114                 crypto_unregister_alg(&cipher_null);
115                 goto out;
116         }
117
118         ret = crypto_register_alg(&compress_null);
119         if (ret < 0) {
120                 crypto_unregister_alg(&digest_null);
121                 crypto_unregister_alg(&cipher_null);
122                 goto out;
123         }
124
125 out:    
126         return ret;
127 }
128
129 static void __exit fini(void)
130 {
131         crypto_unregister_alg(&compress_null);
132         crypto_unregister_alg(&digest_null);
133         crypto_unregister_alg(&cipher_null);
134 }
135
136 module_init(init);
137 module_exit(fini);
138
139 MODULE_LICENSE("GPL");
140 MODULE_DESCRIPTION("Null Cryptographic Algorithms");