blob: 1dc54bb95a876b838f75b46f64c285edf1e064d8 [file] [log] [blame]
Richard Hartmannc9af70f2010-02-16 20:31:54 +08001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * 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.
Richard Hartmannc9af70f2010-02-16 20:31:54 +08008 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07009 * 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 */
Herbert Xu3631c652007-12-13 22:28:59 +080019
Horia Geanta72567252014-03-14 17:46:50 +020020#include <crypto/null.h>
Herbert Xud35d2452008-11-08 08:09:56 +080021#include <crypto/internal/hash.h>
Herbert Xu3631c652007-12-13 22:28:59 +080022#include <crypto/internal/skcipher.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/init.h>
24#include <linux/module.h>
25#include <linux/mm.h>
Patrick McHardyd0856002005-05-16 21:53:41 -070026#include <linux/string.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
Herbert Xu6c2bb982006-05-16 22:09:29 +100028static int null_compress(struct crypto_tfm *tfm, const u8 *src,
29 unsigned int slen, u8 *dst, unsigned int *dlen)
Patrick McHardyd0856002005-05-16 21:53:41 -070030{
31 if (slen > *dlen)
32 return -EINVAL;
33 memcpy(dst, src, slen);
34 *dlen = slen;
35 return 0;
36}
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
Herbert Xud35d2452008-11-08 08:09:56 +080038static int null_init(struct shash_desc *desc)
39{
40 return 0;
41}
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Herbert Xud35d2452008-11-08 08:09:56 +080043static int null_update(struct shash_desc *desc, const u8 *data,
44 unsigned int len)
45{
46 return 0;
47}
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Herbert Xud35d2452008-11-08 08:09:56 +080049static int null_final(struct shash_desc *desc, u8 *out)
50{
51 return 0;
52}
53
54static int null_digest(struct shash_desc *desc, const u8 *data,
55 unsigned int len, u8 *out)
56{
57 return 0;
58}
59
60static int null_hash_setkey(struct crypto_shash *tfm, const u8 *key,
61 unsigned int keylen)
62{ return 0; }
Linus Torvalds1da177e2005-04-16 15:20:36 -070063
Herbert Xu6c2bb982006-05-16 22:09:29 +100064static int null_setkey(struct crypto_tfm *tfm, const u8 *key,
Herbert Xu560c06a2006-08-13 14:16:39 +100065 unsigned int keylen)
Linus Torvalds1da177e2005-04-16 15:20:36 -070066{ return 0; }
67
Herbert Xu6c2bb982006-05-16 22:09:29 +100068static void null_crypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
Patrick McHardyd0856002005-05-16 21:53:41 -070069{
70 memcpy(dst, src, NULL_BLOCK_SIZE);
71}
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
Herbert Xu3631c652007-12-13 22:28:59 +080073static int skcipher_null_crypt(struct blkcipher_desc *desc,
74 struct scatterlist *dst,
75 struct scatterlist *src, unsigned int nbytes)
76{
77 struct blkcipher_walk walk;
78 int err;
79
80 blkcipher_walk_init(&walk, dst, src, nbytes);
81 err = blkcipher_walk_virt(desc, &walk);
82
83 while (walk.nbytes) {
84 if (walk.src.virt.addr != walk.dst.virt.addr)
85 memcpy(walk.dst.virt.addr, walk.src.virt.addr,
86 walk.nbytes);
87 err = blkcipher_walk_done(desc, &walk, 0);
88 }
89
90 return err;
91}
92
Herbert Xud35d2452008-11-08 08:09:56 +080093static struct shash_alg digest_null = {
94 .digestsize = NULL_DIGEST_SIZE,
95 .setkey = null_hash_setkey,
96 .init = null_init,
97 .update = null_update,
98 .finup = null_digest,
99 .digest = null_digest,
100 .final = null_final,
101 .base = {
102 .cra_name = "digest_null",
103 .cra_flags = CRYPTO_ALG_TYPE_SHASH,
104 .cra_blocksize = NULL_BLOCK_SIZE,
105 .cra_module = THIS_MODULE,
106 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107};
108
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300109static struct crypto_alg null_algs[3] = { {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 .cra_name = "cipher_null",
111 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
112 .cra_blocksize = NULL_BLOCK_SIZE,
113 .cra_ctxsize = 0,
114 .cra_module = THIS_MODULE,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 .cra_u = { .cipher = {
116 .cia_min_keysize = NULL_KEY_SIZE,
117 .cia_max_keysize = NULL_KEY_SIZE,
118 .cia_setkey = null_setkey,
Patrick McHardyd0856002005-05-16 21:53:41 -0700119 .cia_encrypt = null_crypt,
120 .cia_decrypt = null_crypt } }
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300121}, {
Herbert Xu3631c652007-12-13 22:28:59 +0800122 .cra_name = "ecb(cipher_null)",
123 .cra_driver_name = "ecb-cipher_null",
124 .cra_priority = 100,
125 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
126 .cra_blocksize = NULL_BLOCK_SIZE,
127 .cra_type = &crypto_blkcipher_type,
128 .cra_ctxsize = 0,
129 .cra_module = THIS_MODULE,
Herbert Xu3631c652007-12-13 22:28:59 +0800130 .cra_u = { .blkcipher = {
131 .min_keysize = NULL_KEY_SIZE,
132 .max_keysize = NULL_KEY_SIZE,
133 .ivsize = NULL_IV_SIZE,
134 .setkey = null_setkey,
135 .encrypt = skcipher_null_crypt,
136 .decrypt = skcipher_null_crypt } }
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300137}, {
138 .cra_name = "compress_null",
139 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
140 .cra_blocksize = NULL_BLOCK_SIZE,
141 .cra_ctxsize = 0,
142 .cra_module = THIS_MODULE,
143 .cra_u = { .compress = {
144 .coa_compress = null_compress,
145 .coa_decompress = null_compress } }
146} };
Herbert Xu3631c652007-12-13 22:28:59 +0800147
Linus Torvalds1da177e2005-04-16 15:20:36 -0700148MODULE_ALIAS("compress_null");
149MODULE_ALIAS("digest_null");
150MODULE_ALIAS("cipher_null");
151
Kamalesh Babulal3af5b902008-04-05 21:00:57 +0800152static int __init crypto_null_mod_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153{
154 int ret = 0;
Richard Hartmannc9af70f2010-02-16 20:31:54 +0800155
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300156 ret = crypto_register_algs(null_algs, ARRAY_SIZE(null_algs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 if (ret < 0)
158 goto out;
159
Herbert Xud35d2452008-11-08 08:09:56 +0800160 ret = crypto_register_shash(&digest_null);
Herbert Xu3631c652007-12-13 22:28:59 +0800161 if (ret < 0)
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300162 goto out_unregister_algs;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300164 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300166out_unregister_algs:
167 crypto_unregister_algs(null_algs, ARRAY_SIZE(null_algs));
Richard Hartmannc9af70f2010-02-16 20:31:54 +0800168out:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 return ret;
170}
171
Kamalesh Babulal3af5b902008-04-05 21:00:57 +0800172static void __exit crypto_null_mod_fini(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173{
Herbert Xud35d2452008-11-08 08:09:56 +0800174 crypto_unregister_shash(&digest_null);
Jussi Kivilinna70a03bf2012-07-11 14:20:00 +0300175 crypto_unregister_algs(null_algs, ARRAY_SIZE(null_algs));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176}
177
Kamalesh Babulal3af5b902008-04-05 21:00:57 +0800178module_init(crypto_null_mod_init);
179module_exit(crypto_null_mod_fini);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180
181MODULE_LICENSE("GPL");
182MODULE_DESCRIPTION("Null Cryptographic Algorithms");