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 | #define ARC4_ALIGN __alignof__(struct arc4_ctx) |
18 | |
19 | static int crypto_arc4_setkey(struct crypto_lskcipher *tfm, const u8 *in_key, |
20 | unsigned int key_len) |
21 | { |
22 | struct arc4_ctx *ctx = crypto_lskcipher_ctx(tfm); |
23 | |
24 | return arc4_setkey(ctx, in_key, key_len); |
25 | } |
26 | |
27 | static int crypto_arc4_crypt(struct crypto_lskcipher *tfm, const u8 *src, |
28 | u8 *dst, unsigned nbytes, u8 *siv, u32 flags) |
29 | { |
30 | struct arc4_ctx *ctx = crypto_lskcipher_ctx(tfm); |
31 | |
32 | if (!(flags & CRYPTO_LSKCIPHER_FLAG_CONT)) |
33 | memcpy(siv, ctx, sizeof(*ctx)); |
34 | |
35 | ctx = (struct arc4_ctx *)siv; |
36 | |
37 | arc4_crypt(ctx, out: dst, in: src, len: nbytes); |
38 | return 0; |
39 | } |
40 | |
41 | static int crypto_arc4_init(struct crypto_lskcipher *tfm) |
42 | { |
43 | pr_warn_ratelimited("\"%s\" (%ld) uses obsolete ecb(arc4) skcipher\n" , |
44 | current->comm, (unsigned long)current->pid); |
45 | |
46 | return 0; |
47 | } |
48 | |
49 | static struct lskcipher_alg arc4_alg = { |
50 | .co.base.cra_name = "arc4" , |
51 | .co.base.cra_driver_name = "arc4-generic" , |
52 | .co.base.cra_priority = 100, |
53 | .co.base.cra_blocksize = ARC4_BLOCK_SIZE, |
54 | .co.base.cra_ctxsize = sizeof(struct arc4_ctx), |
55 | .co.base.cra_alignmask = ARC4_ALIGN - 1, |
56 | .co.base.cra_module = THIS_MODULE, |
57 | .co.min_keysize = ARC4_MIN_KEY_SIZE, |
58 | .co.max_keysize = ARC4_MAX_KEY_SIZE, |
59 | .co.statesize = sizeof(struct arc4_ctx), |
60 | .setkey = crypto_arc4_setkey, |
61 | .encrypt = crypto_arc4_crypt, |
62 | .decrypt = crypto_arc4_crypt, |
63 | .init = crypto_arc4_init, |
64 | }; |
65 | |
66 | static int __init arc4_init(void) |
67 | { |
68 | return crypto_register_lskcipher(alg: &arc4_alg); |
69 | } |
70 | |
71 | static void __exit arc4_exit(void) |
72 | { |
73 | crypto_unregister_lskcipher(alg: &arc4_alg); |
74 | } |
75 | |
76 | subsys_initcall(arc4_init); |
77 | module_exit(arc4_exit); |
78 | |
79 | MODULE_LICENSE("GPL" ); |
80 | MODULE_DESCRIPTION("ARC4 Cipher Algorithm" ); |
81 | MODULE_AUTHOR("Jon Oberheide <jon@oberheide.org>" ); |
82 | MODULE_ALIAS_CRYPTO("ecb(arc4)" ); |
83 | |