1 /*
2 * Cryptographic API.
3 *
4 * Copyright (c) 2013 Chanho Min <chanho.min@lge.com>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 */
20
21 #include <linux/init.h>
22 #include <linux/module.h>
23 #include <linux/crypto.h>
24 #include <linux/vmalloc.h>
25 #include <linux/lz4.h>
26 #include <crypto/internal/scompress.h>
27
28 struct lz4_ctx {
29 void *lz4_comp_mem;
30 };
31
lz4_alloc_ctx(struct crypto_scomp * tfm)32 static void *lz4_alloc_ctx(struct crypto_scomp *tfm)
33 {
34 void *ctx;
35
36 ctx = vmalloc(LZ4_MEM_COMPRESS);
37 if (!ctx)
38 return ERR_PTR(-ENOMEM);
39
40 return ctx;
41 }
42
lz4_init(struct crypto_tfm * tfm)43 static int lz4_init(struct crypto_tfm *tfm)
44 {
45 struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
46
47 ctx->lz4_comp_mem = lz4_alloc_ctx(NULL);
48 if (IS_ERR(ctx->lz4_comp_mem))
49 return -ENOMEM;
50
51 return 0;
52 }
53
lz4_free_ctx(struct crypto_scomp * tfm,void * ctx)54 static void lz4_free_ctx(struct crypto_scomp *tfm, void *ctx)
55 {
56 vfree(ctx);
57 }
58
lz4_exit(struct crypto_tfm * tfm)59 static void lz4_exit(struct crypto_tfm *tfm)
60 {
61 struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
62
63 lz4_free_ctx(NULL, ctx->lz4_comp_mem);
64 }
65
__lz4_compress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)66 static int __lz4_compress_crypto(const u8 *src, unsigned int slen,
67 u8 *dst, unsigned int *dlen, void *ctx)
68 {
69 int out_len = LZ4_compress_default(src, dst,
70 slen, *dlen, ctx);
71
72 if (!out_len)
73 return -EINVAL;
74
75 *dlen = out_len;
76 return 0;
77 }
78
lz4_scompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)79 static int lz4_scompress(struct crypto_scomp *tfm, const u8 *src,
80 unsigned int slen, u8 *dst, unsigned int *dlen,
81 void *ctx)
82 {
83 return __lz4_compress_crypto(src, slen, dst, dlen, ctx);
84 }
85
lz4_compress_crypto(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)86 static int lz4_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
87 unsigned int slen, u8 *dst, unsigned int *dlen)
88 {
89 struct lz4_ctx *ctx = crypto_tfm_ctx(tfm);
90
91 return __lz4_compress_crypto(src, slen, dst, dlen, ctx->lz4_comp_mem);
92 }
93
__lz4_decompress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)94 static int __lz4_decompress_crypto(const u8 *src, unsigned int slen,
95 u8 *dst, unsigned int *dlen, void *ctx)
96 {
97 int out_len = LZ4_decompress_safe(src, dst, slen, *dlen);
98
99 if (out_len < 0)
100 return -EINVAL;
101
102 *dlen = out_len;
103 return 0;
104 }
105
lz4_sdecompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)106 static int lz4_sdecompress(struct crypto_scomp *tfm, const u8 *src,
107 unsigned int slen, u8 *dst, unsigned int *dlen,
108 void *ctx)
109 {
110 return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
111 }
112
lz4_decompress_crypto(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)113 static int lz4_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
114 unsigned int slen, u8 *dst,
115 unsigned int *dlen)
116 {
117 return __lz4_decompress_crypto(src, slen, dst, dlen, NULL);
118 }
119
120 static struct crypto_alg alg_lz4 = {
121 .cra_name = "lz4",
122 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
123 .cra_ctxsize = sizeof(struct lz4_ctx),
124 .cra_module = THIS_MODULE,
125 .cra_list = LIST_HEAD_INIT(alg_lz4.cra_list),
126 .cra_init = lz4_init,
127 .cra_exit = lz4_exit,
128 .cra_u = { .compress = {
129 .coa_compress = lz4_compress_crypto,
130 .coa_decompress = lz4_decompress_crypto } }
131 };
132
133 static struct scomp_alg scomp = {
134 .alloc_ctx = lz4_alloc_ctx,
135 .free_ctx = lz4_free_ctx,
136 .compress = lz4_scompress,
137 .decompress = lz4_sdecompress,
138 .base = {
139 .cra_name = "lz4",
140 .cra_driver_name = "lz4-scomp",
141 .cra_module = THIS_MODULE,
142 }
143 };
144
lz4_mod_init(void)145 static int __init lz4_mod_init(void)
146 {
147 int ret;
148
149 ret = crypto_register_alg(&alg_lz4);
150 if (ret)
151 return ret;
152
153 ret = crypto_register_scomp(&scomp);
154 if (ret) {
155 crypto_unregister_alg(&alg_lz4);
156 return ret;
157 }
158
159 return ret;
160 }
161
lz4_mod_fini(void)162 static void __exit lz4_mod_fini(void)
163 {
164 crypto_unregister_alg(&alg_lz4);
165 crypto_unregister_scomp(&scomp);
166 }
167
168 module_init(lz4_mod_init);
169 module_exit(lz4_mod_fini);
170
171 MODULE_LICENSE("GPL");
172 MODULE_DESCRIPTION("LZ4 Compression Algorithm");
173 MODULE_ALIAS_CRYPTO("lz4");
174
