aboutsummaryrefslogtreecommitdiff
path: root/crypto/lzo.c
blob: 97051a2ca08ed50f4dadbffeb9463bfbabda1d63 (plain)
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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Cryptographic API.
 */

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

struct lzo_ctx {
	void *lzo_comp_mem;
};

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

	ctx = kvmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
	if (!ctx)
		return ERR_PTR(-ENOMEM);

	return ctx;
}

static int lzo_init(struct crypto_tfm *tfm)
{
	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);

	ctx->lzo_comp_mem = lzo_alloc_ctx(NULL);
	if (IS_ERR(ctx->lzo_comp_mem))
		return -ENOMEM;

	return 0;
}

static void lzo_free_ctx(struct crypto_scomp *tfm, void *ctx)
{
	kvfree(ctx);
}

static void lzo_exit(struct crypto_tfm *tfm)
{
	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);

	lzo_free_ctx(NULL, ctx->lzo_comp_mem);
}

static int __lzo_compress(const u8 *src, unsigned int slen,
			  u8 *dst, unsigned int *dlen, void *ctx)
{
	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
	int err;

	err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx);

	if (err != LZO_E_OK)
		return -EINVAL;

	*dlen = tmp_len;
	return 0;
}

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

	return __lzo_compress(src, slen, dst, dlen, ctx->lzo_comp_mem);
}

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

static int __lzo_decompress(const u8 *src, unsigned int slen,
			    u8 *dst, unsigned int *dlen)
{
	int err;
	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */

	err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);

	if (err != LZO_E_OK)
		return -EINVAL;

	*dlen = tmp_len;
	return 0;
}

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

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

static struct crypto_alg alg = {
	.cra_name		= "lzo",
	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
	.cra_ctxsize		= sizeof(struct lzo_ctx),
	.cra_module		= THIS_MODULE,
	.cra_init		= lzo_init,
	.cra_exit		= lzo_exit,
	.cra_u			= { .compress = {
	.coa_compress		= lzo_compress,
	.coa_decompress		= lzo_decompress } }
};

static struct scomp_alg scomp = {
	.alloc_ctx		= lzo_alloc_ctx,
	.free_ctx		= lzo_free_ctx,
	.compress		= lzo_scompress,
	.decompress		= lzo_sdecompress,
	.base			= {
		.cra_name	= "lzo",
		.cra_driver_name = "lzo-scomp",
		.cra_module	 = THIS_MODULE,
	}
};

static int __init lzo_mod_init(void)
{
	int ret;

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

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

	return ret;
}

static void __exit lzo_mod_fini(void)
{
	crypto_unregister_alg(&alg);
	crypto_unregister_scomp(&scomp);
}

subsys_initcall(lzo_mod_init);
module_exit(lzo_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO Compression Algorithm");
MODULE_ALIAS_CRYPTO("lzo");