lz4hc.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Cryptographic API.
 4 *
 5 * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
 6 */
 7#include <crypto/internal/scompress.h>
 8#include <linux/init.h>
 9#include <linux/module.h>
10#include <linux/vmalloc.h>
11#include <linux/lz4.h>
12
13static void *lz4hc_alloc_ctx(void)
14{
15	void *ctx;
16
17	ctx = vmalloc(LZ4HC_MEM_COMPRESS);
18	if (!ctx)
19		return ERR_PTR(-ENOMEM);
20
21	return ctx;
22}
23
24static void lz4hc_free_ctx(void *ctx)
25{
26	vfree(ctx);
27}
28
29static int __lz4hc_compress_crypto(const u8 *src, unsigned int slen,
30				   u8 *dst, unsigned int *dlen, void *ctx)
31{
32	int out_len = LZ4_compress_HC(src, dst, slen,
33		*dlen, LZ4HC_DEFAULT_CLEVEL, ctx);
34
35	if (!out_len)
36		return -EINVAL;
37
38	*dlen = out_len;
39	return 0;
40}
41
42static int lz4hc_scompress(struct crypto_scomp *tfm, const u8 *src,
43			   unsigned int slen, u8 *dst, unsigned int *dlen,
44			   void *ctx)
45{
46	return __lz4hc_compress_crypto(src, slen, dst, dlen, ctx);
47}
48
49static int __lz4hc_decompress_crypto(const u8 *src, unsigned int slen,
50				     u8 *dst, unsigned int *dlen, void *ctx)
51{
52	int out_len = LZ4_decompress_safe(src, dst, slen, *dlen);
53
54	if (out_len < 0)
55		return -EINVAL;
56
57	*dlen = out_len;
58	return 0;
59}
60
61static int lz4hc_sdecompress(struct crypto_scomp *tfm, const u8 *src,
62			     unsigned int slen, u8 *dst, unsigned int *dlen,
63			     void *ctx)
64{
65	return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL);
66}
67
68static struct scomp_alg scomp = {
69	.streams		= {
70		.alloc_ctx	= lz4hc_alloc_ctx,
71		.free_ctx	= lz4hc_free_ctx,
72	},
73	.compress		= lz4hc_scompress,
74	.decompress		= lz4hc_sdecompress,
75	.base			= {
76		.cra_name	= "lz4hc",
77		.cra_driver_name = "lz4hc-scomp",
78		.cra_module	 = THIS_MODULE,
79	}
80};
81
82static int __init lz4hc_mod_init(void)
83{
84	return crypto_register_scomp(&scomp);
85}
86
87static void __exit lz4hc_mod_fini(void)
88{
89	crypto_unregister_scomp(&scomp);
90}
91
92module_init(lz4hc_mod_init);
93module_exit(lz4hc_mod_fini);
94
95MODULE_LICENSE("GPL");
96MODULE_DESCRIPTION("LZ4HC Compression Algorithm");
97MODULE_ALIAS_CRYPTO("lz4hc");