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
lzo_init(struct crypto_tfm * tfm)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 | __GFP_REPEAT);
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
lzo_exit(struct crypto_tfm * tfm)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
lzo_compress(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)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
lzo_decompress(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)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
lzo_mod_init(void)95 static int __init lzo_mod_init(void)
96 {
97 return crypto_register_alg(&alg);
98 }
99
lzo_mod_fini(void)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