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/lzo.h>
24
25 struct lzo_ctx {
26 void *lzo_comp_mem;
27 };
28
lzo_init(struct crypto_tfm * tfm)29 static int lzo_init(struct crypto_tfm *tfm)
30 {
31 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
32
33 ctx->lzo_comp_mem = vmalloc(LZO1X_MEM_COMPRESS);
34 if (!ctx->lzo_comp_mem)
35 return -ENOMEM;
36
37 return 0;
38 }
39
lzo_exit(struct crypto_tfm * tfm)40 static void lzo_exit(struct crypto_tfm *tfm)
41 {
42 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
43
44 vfree(ctx->lzo_comp_mem);
45 }
46
lzo_compress(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)47 static int lzo_compress(struct crypto_tfm *tfm, const u8 *src,
48 unsigned int slen, u8 *dst, unsigned int *dlen)
49 {
50 struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
51 size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
52 int err;
53
54 err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx->lzo_comp_mem);
55
56 if (err != LZO_E_OK)
57 return -EINVAL;
58
59 *dlen = tmp_len;
60 return 0;
61 }
62
lzo_decompress(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)63 static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src,
64 unsigned int slen, u8 *dst, unsigned int *dlen)
65 {
66 int err;
67 size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
68
69 err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);
70
71 if (err != LZO_E_OK)
72 return -EINVAL;
73
74 *dlen = tmp_len;
75 return 0;
76
77 }
78
79 static struct crypto_alg alg = {
80 .cra_name = "lzo",
81 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
82 .cra_ctxsize = sizeof(struct lzo_ctx),
83 .cra_module = THIS_MODULE,
84 .cra_list = LIST_HEAD_INIT(alg.cra_list),
85 .cra_init = lzo_init,
86 .cra_exit = lzo_exit,
87 .cra_u = { .compress = {
88 .coa_compress = lzo_compress,
89 .coa_decompress = lzo_decompress } }
90 };
91
lzo_mod_init(void)92 static int __init lzo_mod_init(void)
93 {
94 return crypto_register_alg(&alg);
95 }
96
lzo_mod_fini(void)97 static void __exit lzo_mod_fini(void)
98 {
99 crypto_unregister_alg(&alg);
100 }
101
102 module_init(lzo_mod_init);
103 module_exit(lzo_mod_fini);
104
105 MODULE_LICENSE("GPL");
106 MODULE_DESCRIPTION("LZO Compression Algorithm");
107