summaryrefslogtreecommitdiff
path: root/crypto/lz4.c
blob: 54673cf88385a83d242acc8398e4f79038b5c60a (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Cryptographic API.
 *
 * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
 */

#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)
{
	int out_len = LZ4_compress_default(src, dst,
		slen, *dlen, ctx);

	if (!out_len)
		return -EINVAL;

	*dlen = out_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 out_len = LZ4_decompress_safe(src, dst, slen, *dlen);

	if (out_len < 0)
		return -EINVAL;

	*dlen = out_len;
	return 0;
}

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_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);
}

subsys_initcall(lz4_mod_init);
module_exit(lz4_mod_fini);

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