xref: /linux/crypto/arc4.c (revision ebc733e54a1a79ea2dde2ba5121ae73a188e20d4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cryptographic API
4  *
5  * ARC4 Cipher Algorithm
6  *
7  * Jon Oberheide <jon@oberheide.org>
8  */
9 
10 #include <crypto/arc4.h>
11 #include <crypto/internal/skcipher.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/sched.h>
16 
17 static int crypto_arc4_setkey(struct crypto_lskcipher *tfm, const u8 *in_key,
18 			      unsigned int key_len)
19 {
20 	struct arc4_ctx *ctx = crypto_lskcipher_ctx(tfm);
21 
22 	return arc4_setkey(ctx, in_key, key_len);
23 }
24 
25 static int crypto_arc4_crypt(struct crypto_lskcipher *tfm, const u8 *src,
26 			     u8 *dst, unsigned nbytes, u8 *iv, bool final)
27 {
28 	struct arc4_ctx *ctx = crypto_lskcipher_ctx(tfm);
29 
30 	arc4_crypt(ctx, dst, src, nbytes);
31 	return 0;
32 }
33 
34 static int crypto_arc4_init(struct crypto_lskcipher *tfm)
35 {
36 	pr_warn_ratelimited("\"%s\" (%ld) uses obsolete ecb(arc4) skcipher\n",
37 			    current->comm, (unsigned long)current->pid);
38 
39 	return 0;
40 }
41 
42 static struct lskcipher_alg arc4_alg = {
43 	.co.base.cra_name		=	"arc4",
44 	.co.base.cra_driver_name	=	"arc4-generic",
45 	.co.base.cra_priority		=	100,
46 	.co.base.cra_blocksize		=	ARC4_BLOCK_SIZE,
47 	.co.base.cra_ctxsize		=	sizeof(struct arc4_ctx),
48 	.co.base.cra_module		=	THIS_MODULE,
49 	.co.min_keysize			=	ARC4_MIN_KEY_SIZE,
50 	.co.max_keysize			=	ARC4_MAX_KEY_SIZE,
51 	.setkey				=	crypto_arc4_setkey,
52 	.encrypt			=	crypto_arc4_crypt,
53 	.decrypt			=	crypto_arc4_crypt,
54 	.init				=	crypto_arc4_init,
55 };
56 
57 static int __init arc4_init(void)
58 {
59 	return crypto_register_lskcipher(&arc4_alg);
60 }
61 
62 static void __exit arc4_exit(void)
63 {
64 	crypto_unregister_lskcipher(&arc4_alg);
65 }
66 
67 subsys_initcall(arc4_init);
68 module_exit(arc4_exit);
69 
70 MODULE_LICENSE("GPL");
71 MODULE_DESCRIPTION("ARC4 Cipher Algorithm");
72 MODULE_AUTHOR("Jon Oberheide <jon@oberheide.org>");
73 MODULE_ALIAS_CRYPTO("ecb(arc4)");
74