Commit | Line | Data |
---|---|---|
1da177e4 LT |
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 | ||
25 | #define NULL_KEY_SIZE 0 | |
26 | #define NULL_BLOCK_SIZE 1 | |
27 | #define NULL_DIGEST_SIZE 0 | |
28 | ||
29 | static int null_compress(void *ctx, const u8 *src, unsigned int slen, | |
30 | u8 *dst, unsigned int *dlen) | |
31 | { return 0; } | |
32 | ||
33 | static int null_decompress(void *ctx, const u8 *src, unsigned int slen, | |
34 | u8 *dst, unsigned int *dlen) | |
35 | { return 0; } | |
36 | ||
37 | static void null_init(void *ctx) | |
38 | { } | |
39 | ||
40 | static void null_update(void *ctx, const u8 *data, unsigned int len) | |
41 | { } | |
42 | ||
43 | static void null_final(void *ctx, u8 *out) | |
44 | { } | |
45 | ||
46 | static int null_setkey(void *ctx, const u8 *key, | |
47 | unsigned int keylen, u32 *flags) | |
48 | { return 0; } | |
49 | ||
50 | static void null_encrypt(void *ctx, u8 *dst, const u8 *src) | |
51 | { } | |
52 | ||
53 | static void null_decrypt(void *ctx, u8 *dst, const u8 *src) | |
54 | { } | |
55 | ||
56 | static struct crypto_alg compress_null = { | |
57 | .cra_name = "compress_null", | |
58 | .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, | |
59 | .cra_blocksize = NULL_BLOCK_SIZE, | |
60 | .cra_ctxsize = 0, | |
61 | .cra_module = THIS_MODULE, | |
62 | .cra_list = LIST_HEAD_INIT(compress_null.cra_list), | |
63 | .cra_u = { .compress = { | |
64 | .coa_compress = null_compress, | |
65 | .coa_decompress = null_decompress } } | |
66 | }; | |
67 | ||
68 | static struct crypto_alg digest_null = { | |
69 | .cra_name = "digest_null", | |
70 | .cra_flags = CRYPTO_ALG_TYPE_DIGEST, | |
71 | .cra_blocksize = NULL_BLOCK_SIZE, | |
72 | .cra_ctxsize = 0, | |
73 | .cra_module = THIS_MODULE, | |
74 | .cra_list = LIST_HEAD_INIT(digest_null.cra_list), | |
75 | .cra_u = { .digest = { | |
76 | .dia_digestsize = NULL_DIGEST_SIZE, | |
77 | .dia_init = null_init, | |
78 | .dia_update = null_update, | |
79 | .dia_final = null_final } } | |
80 | }; | |
81 | ||
82 | static struct crypto_alg cipher_null = { | |
83 | .cra_name = "cipher_null", | |
84 | .cra_flags = CRYPTO_ALG_TYPE_CIPHER, | |
85 | .cra_blocksize = NULL_BLOCK_SIZE, | |
86 | .cra_ctxsize = 0, | |
87 | .cra_module = THIS_MODULE, | |
88 | .cra_list = LIST_HEAD_INIT(cipher_null.cra_list), | |
89 | .cra_u = { .cipher = { | |
90 | .cia_min_keysize = NULL_KEY_SIZE, | |
91 | .cia_max_keysize = NULL_KEY_SIZE, | |
92 | .cia_setkey = null_setkey, | |
93 | .cia_encrypt = null_encrypt, | |
94 | .cia_decrypt = null_decrypt } } | |
95 | }; | |
96 | ||
97 | MODULE_ALIAS("compress_null"); | |
98 | MODULE_ALIAS("digest_null"); | |
99 | MODULE_ALIAS("cipher_null"); | |
100 | ||
101 | static int __init init(void) | |
102 | { | |
103 | int ret = 0; | |
104 | ||
105 | ret = crypto_register_alg(&cipher_null); | |
106 | if (ret < 0) | |
107 | goto out; | |
108 | ||
109 | ret = crypto_register_alg(&digest_null); | |
110 | if (ret < 0) { | |
111 | crypto_unregister_alg(&cipher_null); | |
112 | goto out; | |
113 | } | |
114 | ||
115 | ret = crypto_register_alg(&compress_null); | |
116 | if (ret < 0) { | |
117 | crypto_unregister_alg(&digest_null); | |
118 | crypto_unregister_alg(&cipher_null); | |
119 | goto out; | |
120 | } | |
121 | ||
122 | out: | |
123 | return ret; | |
124 | } | |
125 | ||
126 | static void __exit fini(void) | |
127 | { | |
128 | crypto_unregister_alg(&compress_null); | |
129 | crypto_unregister_alg(&digest_null); | |
130 | crypto_unregister_alg(&cipher_null); | |
131 | } | |
132 | ||
133 | module_init(init); | |
134 | module_exit(fini); | |
135 | ||
136 | MODULE_LICENSE("GPL"); | |
137 | MODULE_DESCRIPTION("Null Cryptographic Algorithms"); |