blob: c3f3dd9a28c5eb1ca8546272ebec13f3f0a84cc3
1 | /* |
2 | * Cryptographic API. |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify it |
5 | * under the terms of the GNU General Public License version 2 as published by |
6 | * the Free Software Foundation. |
7 | * |
8 | * This program is distributed in the hope that it will be useful, but WITHOUT |
9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
11 | * more details. |
12 | * |
13 | * You should have received a copy of the GNU General Public License along with |
14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
15 | * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
16 | * |
17 | */ |
18 | |
19 | #include <linux/init.h> |
20 | #include <linux/module.h> |
21 | #include <linux/crypto.h> |
22 | #include <linux/vmalloc.h> |
23 | #include <linux/mm.h> |
24 | #include <linux/lzo.h> |
25 | |
26 | struct lzo_ctx { |
27 | void *lzo_comp_mem; |
28 | }; |
29 | |
30 | static int lzo_init(struct crypto_tfm *tfm) |
31 | { |
32 | struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); |
33 | |
34 | ctx->lzo_comp_mem = kmalloc(LZO1X_MEM_COMPRESS, |
35 | GFP_KERNEL | __GFP_NOWARN); |
36 | if (!ctx->lzo_comp_mem) |
37 | ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS); |
38 | if (!ctx->lzo_comp_mem) |
39 | return -ENOMEM; |
40 | |
41 | return 0; |
42 | } |
43 | |
44 | static void lzo_exit(struct crypto_tfm *tfm) |
45 | { |
46 | struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); |
47 | |
48 | kvfree(ctx->lzo_comp_mem); |
49 | } |
50 | |
51 | static int lzo_compress(struct crypto_tfm *tfm, const u8 *src, |
52 | unsigned int slen, u8 *dst, unsigned int *dlen) |
53 | { |
54 | struct lzo_ctx *ctx = crypto_tfm_ctx(tfm); |
55 | size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ |
56 | int err; |
57 | |
58 | err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx->lzo_comp_mem); |
59 | |
60 | if (err != LZO_E_OK) |
61 | return -EINVAL; |
62 | |
63 | *dlen = tmp_len; |
64 | return 0; |
65 | } |
66 | |
67 | static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src, |
68 | unsigned int slen, u8 *dst, unsigned int *dlen) |
69 | { |
70 | int err; |
71 | size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ |
72 | |
73 | err = lzo1x_decompress_safe(src, slen, dst, &tmp_len); |
74 | |
75 | if (err != LZO_E_OK) |
76 | return -EINVAL; |
77 | |
78 | *dlen = tmp_len; |
79 | return 0; |
80 | |
81 | } |
82 | |
83 | static struct crypto_alg alg = { |
84 | .cra_name = "lzo", |
85 | .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, |
86 | .cra_ctxsize = sizeof(struct lzo_ctx), |
87 | .cra_module = THIS_MODULE, |
88 | .cra_init = lzo_init, |
89 | .cra_exit = lzo_exit, |
90 | .cra_u = { .compress = { |
91 | .coa_compress = lzo_compress, |
92 | .coa_decompress = lzo_decompress } } |
93 | }; |
94 | |
95 | static int __init lzo_mod_init(void) |
96 | { |
97 | return crypto_register_alg(&alg); |
98 | } |
99 | |
100 | static void __exit lzo_mod_fini(void) |
101 | { |
102 | crypto_unregister_alg(&alg); |
103 | } |
104 | |
105 | module_init(lzo_mod_init); |
106 | module_exit(lzo_mod_fini); |
107 | |
108 | MODULE_LICENSE("GPL"); |
109 | MODULE_DESCRIPTION("LZO Compression Algorithm"); |
110 | MODULE_ALIAS_CRYPTO("lzo"); |
111 |