1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * CBC: Cipher Block Chaining mode
5 * Copyright (c) 2006-2016 Herbert Xu <herbert@gondor.apana.org.au>
8 #include <crypto/algapi.h>
9 #include <crypto/cbc.h>
10 #include <crypto/internal/skcipher.h>
11 #include <linux/err.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/log2.h>
15 #include <linux/module.h>
17 static inline void crypto_cbc_encrypt_one(struct crypto_skcipher *tfm,
18 const u8 *src, u8 *dst)
20 crypto_cipher_encrypt_one(skcipher_cipher_simple(tfm), dst, src);
23 static int crypto_cbc_encrypt(struct skcipher_request *req)
25 return crypto_cbc_encrypt_walk(req, crypto_cbc_encrypt_one);
28 static inline void crypto_cbc_decrypt_one(struct crypto_skcipher *tfm,
29 const u8 *src, u8 *dst)
31 crypto_cipher_decrypt_one(skcipher_cipher_simple(tfm), dst, src);
34 static int crypto_cbc_decrypt(struct skcipher_request *req)
36 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
37 struct skcipher_walk walk;
40 err = skcipher_walk_virt(&walk, req, false);
43 err = crypto_cbc_decrypt_blocks(&walk, tfm,
44 crypto_cbc_decrypt_one);
45 err = skcipher_walk_done(&walk, err);
51 static int crypto_cbc_create(struct crypto_template *tmpl, struct rtattr **tb)
53 struct skcipher_instance *inst;
54 struct crypto_alg *alg;
57 inst = skcipher_alloc_instance_simple(tmpl, tb);
61 alg = skcipher_ialg_simple(inst);
64 if (!is_power_of_2(alg->cra_blocksize))
67 inst->alg.encrypt = crypto_cbc_encrypt;
68 inst->alg.decrypt = crypto_cbc_decrypt;
70 err = skcipher_register_instance(tmpl, inst);
79 static struct crypto_template crypto_cbc_tmpl = {
81 .create = crypto_cbc_create,
82 .module = THIS_MODULE,
85 static int __init crypto_cbc_module_init(void)
87 return crypto_register_template(&crypto_cbc_tmpl);
90 static void __exit crypto_cbc_module_exit(void)
92 crypto_unregister_template(&crypto_cbc_tmpl);
95 subsys_initcall(crypto_cbc_module_init);
96 module_exit(crypto_cbc_module_exit);
98 MODULE_LICENSE("GPL");
99 MODULE_DESCRIPTION("CBC block cipher mode of operation");
100 MODULE_ALIAS_CRYPTO("cbc");