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
8 #include <linux/init.h>
9 #include <linux/module.h>
10 #include <linux/crypto.h>
11 #include <linux/vmalloc.h>
12 #include <linux/lz4.h>
13 #include <crypto/internal/scompress.h>
14
15 struct lz4_ctx {
16 void *lz4_comp_mem;
17 };
18
lz4_alloc_ctx(void)19 static void *lz4_alloc_ctx(void)
20 {
21 void *ctx;
22
23 ctx = vmalloc(LZ4_MEM_COMPRESS);
24 if (!ctx)
25 return ERR_PTR(-ENOMEM);
26
27 return ctx;
28 }
29
lz4_free_ctx(void * ctx)30 static void lz4_free_ctx(void *ctx)
31 {
32 vfree(ctx);
33 }
34
__lz4_compress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)35 static int __lz4_compress_crypto(const u8 *src, unsigned int slen,
36 u8 *dst, unsigned int *dlen, void *ctx)
37 {
38 int out_len = LZ4_compress_default(src, dst,
39 slen, *dlen, ctx);
40
41 if (!out_len)
42 return -EINVAL;
43
44 *dlen = out_len;
45 return 0;
46 }
47
lz4_scompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)48 static int lz4_scompress(struct crypto_scomp *tfm, const u8 *src,
49 unsigned int slen, u8 *dst, unsigned int *dlen,
50 void *ctx)
51 {
52 return __lz4_compress_crypto(src, slen, dst, dlen, ctx);
53 }
54
__lz4_decompress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)55 static int __lz4_decompress_crypto(const u8 *src, unsigned int slen,
56 u8 *dst, unsigned int *dlen, void *ctx)
57 {
58 int out_len = LZ4_decompress_safe(src, dst, slen, *dlen);
59
60 if (out_len < 0)
61 return -EINVAL;
62
63 *dlen = out_len;
64 return 0;
65 }
66
lz4_sdecompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)67 static int lz4_sdecompress(struct crypto_scomp *tfm, const u8 *src,
68 unsigned int slen, u8 *dst, unsigned int *dlen,
69 void *ctx)
70 {
71 return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
72 }
73
74 static struct scomp_alg scomp = {
75 .alloc_ctx = lz4_alloc_ctx,
76 .free_ctx = lz4_free_ctx,
77 .compress = lz4_scompress,
78 .decompress = lz4_sdecompress,
79 .base = {
80 .cra_name = "lz4",
81 .cra_driver_name = "lz4-scomp",
82 .cra_module = THIS_MODULE,
83 }
84 };
85
lz4_mod_init(void)86 static int __init lz4_mod_init(void)
87 {
88 return crypto_register_scomp(&scomp);
89 }
90
lz4_mod_fini(void)91 static void __exit lz4_mod_fini(void)
92 {
93 crypto_unregister_scomp(&scomp);
94 }
95
96 subsys_initcall(lz4_mod_init);
97 module_exit(lz4_mod_fini);
98
99 MODULE_LICENSE("GPL");
100 MODULE_DESCRIPTION("LZ4 Compression Algorithm");
101 MODULE_ALIAS_CRYPTO("lz4");
102