summaryrefslogtreecommitdiff
path: root/crypto/lz4.c
blob: 99c1b2cc2976ad31aca9cfef182bf0318b6e95af (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
/*
 * Cryptographic API.
 *
 * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/crypto.h>
#include <linux/vmalloc.h>
#include <linux/lz4.h>
#include <crypto/internal/scompress.h>

struct lz4_ctx {
	void *lz4_comp_mem;
};

static void *lz4_alloc_ctx(struct crypto_scomp *tfm)
{
	void *ctx;

	ctx = vmalloc(LZ4_MEM_COMPRESS);
	if (!ctx)
		return ERR_PTR(-ENOMEM);

	return ctx;
}

static int lz4_init(struct crypto_tfm *tfm)
{
	struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);

	ctx->lz4_comp_mem = lz4_alloc_ctx(NULL);
	if (IS_ERR(ctx->lz4_comp_mem))
		return -ENOMEM;

	return 0;
}

static void lz4_free_ctx(struct crypto_scomp *tfm, void *ctx)
{
	vfree(ctx);
}

static void lz4_exit(struct crypto_tfm *tfm)
{
	struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);

	lz4_free_ctx(NULL, ctx->lz4_comp_mem);
}

static int __lz4_compress_crypto(const u8 *src, unsigned int slen,
				 u8 *dst, unsigned int *dlen, void *ctx)
{
	size_t tmp_len = *dlen;
	int err;

	err = lz4_compress(src, slen, dst, &tmp_len, ctx);

	if (err < 0)
		return -EINVAL;

	*dlen = tmp_len;
	return 0;
}

static int lz4_scompress(struct crypto_scomp *tfm, const u8 *src,
			 unsigned int slen, u8 *dst, unsigned int *dlen,
			 void *ctx)
{
	return __lz4_compress_crypto(src, slen, dst, dlen, ctx);
}

static int lz4_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
			       unsigned int slen, u8 *dst, unsigned int *dlen)
{
	struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);

	return __lz4_compress_crypto(src, slen, dst, dlen, ctx->lz4_comp_mem);
}

static int __lz4_decompress_crypto(const u8 *src, unsigned int slen,
				   u8 *dst, unsigned int *dlen, void *ctx)
{
	int err;
	size_t tmp_len = *dlen;
	size_t __slen = slen;

	err = lz4_decompress_unknownoutputsize(src, __slen, dst, &tmp_len);
	if (err < 0)
		return -EINVAL;

	*dlen = tmp_len;
	return err;
}

static int lz4_sdecompress(struct crypto_scomp *tfm, const u8 *src,
			   unsigned int slen, u8 *dst, unsigned int *dlen,
			   void *ctx)
{
	return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
}

static int lz4_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
				 unsigned int slen, u8 *dst,
				 unsigned int *dlen)
{
	return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
}

static struct crypto_alg alg_lz4 = {
	.cra_name		= "lz4",
	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
	.cra_ctxsize		= sizeof(struct lz4_ctx),
	.cra_module		= THIS_MODULE,
	.cra_list		= LIST_HEAD_INIT(alg_lz4.cra_list),
	.cra_init		= lz4_init,
	.cra_exit		= lz4_exit,
	.cra_u			= { .compress = {
	.coa_compress		= lz4_compress_crypto,
	.coa_decompress		= lz4_decompress_crypto } }
};

static struct scomp_alg scomp = {
	.alloc_ctx		= lz4_alloc_ctx,
	.free_ctx		= lz4_free_ctx,
	.compress		= lz4_scompress,
	.decompress		= lz4_sdecompress,
	.base			= {
		.cra_name	= "lz4",
		.cra_driver_name = "lz4-scomp",
		.cra_module	 = THIS_MODULE,
	}
};

static int __init lz4_mod_init(void)
{
	int ret;

	ret = crypto_register_alg(&alg_lz4);
	if (ret)
		return ret;

	ret = crypto_register_scomp(&scomp);
	if (ret) {
		crypto_unregister_alg(&alg_lz4);
		return ret;
	}

	return ret;
}

static void __exit lz4_mod_fini(void)
{
	crypto_unregister_alg(&alg_lz4);
	crypto_unregister_scomp(&scomp);
}

module_init(lz4_mod_init);
module_exit(lz4_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZ4 Compression Algorithm");
MODULE_ALIAS_CRYPTO("lz4");