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 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/crypto.h>
23 #include <linux/vmalloc.h>
24 #include <linux/lz4.h>
25 #include <crypto/internal/scompress.h>
26
27 struct lz4hc_ctx {
28 void *lz4hc_comp_mem;
29 };
30
lz4hc_alloc_ctx(struct crypto_scomp * tfm)31 static void *lz4hc_alloc_ctx(struct crypto_scomp *tfm)
32 {
33 void *ctx;
34
35 ctx = vmalloc(LZ4HC_MEM_COMPRESS);
36 if (!ctx)
37 return ERR_PTR(-ENOMEM);
38
39 return ctx;
40 }
41
lz4hc_init(struct crypto_tfm * tfm)42 static int lz4hc_init(struct crypto_tfm *tfm)
43 {
44 struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
45
46 ctx->lz4hc_comp_mem = lz4hc_alloc_ctx(NULL);
47 if (IS_ERR(ctx->lz4hc_comp_mem))
48 return -ENOMEM;
49
50 return 0;
51 }
52
lz4hc_free_ctx(struct crypto_scomp * tfm,void * ctx)53 static void lz4hc_free_ctx(struct crypto_scomp *tfm, void *ctx)
54 {
55 vfree(ctx);
56 }
57
lz4hc_exit(struct crypto_tfm * tfm)58 static void lz4hc_exit(struct crypto_tfm *tfm)
59 {
60 struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
61
62 lz4hc_free_ctx(NULL, ctx->lz4hc_comp_mem);
63 }
64
__lz4hc_compress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)65 static int __lz4hc_compress_crypto(const u8 *src, unsigned int slen,
66 u8 *dst, unsigned int *dlen, void *ctx)
67 {
68 int out_len = LZ4_compress_HC(src, dst, slen,
69 *dlen, LZ4HC_DEFAULT_CLEVEL, ctx);
70
71 if (!out_len)
72 return -EINVAL;
73
74 *dlen = out_len;
75 return 0;
76 }
77
lz4hc_scompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)78 static int lz4hc_scompress(struct crypto_scomp *tfm, const u8 *src,
79 unsigned int slen, u8 *dst, unsigned int *dlen,
80 void *ctx)
81 {
82 return __lz4hc_compress_crypto(src, slen, dst, dlen, ctx);
83 }
84
lz4hc_compress_crypto(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)85 static int lz4hc_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
86 unsigned int slen, u8 *dst,
87 unsigned int *dlen)
88 {
89 struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
90
91 return __lz4hc_compress_crypto(src, slen, dst, dlen,
92 ctx->lz4hc_comp_mem);
93 }
94
__lz4hc_decompress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)95 static int __lz4hc_decompress_crypto(const u8 *src, unsigned int slen,
96 u8 *dst, unsigned int *dlen, void *ctx)
97 {
98 int out_len = LZ4_decompress_safe(src, dst, slen, *dlen);
99
100 if (out_len < 0)
101 return -EINVAL;
102
103 *dlen = out_len;
104 return 0;
105 }
106
lz4hc_sdecompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)107 static int lz4hc_sdecompress(struct crypto_scomp *tfm, const u8 *src,
108 unsigned int slen, u8 *dst, unsigned int *dlen,
109 void *ctx)
110 {
111 return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL);
112 }
113
lz4hc_decompress_crypto(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)114 static int lz4hc_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
115 unsigned int slen, u8 *dst,
116 unsigned int *dlen)
117 {
118 return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL);
119 }
120
121 static struct crypto_alg alg_lz4hc = {
122 .cra_name = "lz4hc",
123 .cra_flags = CRYPTO_ALG_TYPE_COMPRESS,
124 .cra_ctxsize = sizeof(struct lz4hc_ctx),
125 .cra_module = THIS_MODULE,
126 .cra_list = LIST_HEAD_INIT(alg_lz4hc.cra_list),
127 .cra_init = lz4hc_init,
128 .cra_exit = lz4hc_exit,
129 .cra_u = { .compress = {
130 .coa_compress = lz4hc_compress_crypto,
131 .coa_decompress = lz4hc_decompress_crypto } }
132 };
133
134 static struct scomp_alg scomp = {
135 .alloc_ctx = lz4hc_alloc_ctx,
136 .free_ctx = lz4hc_free_ctx,
137 .compress = lz4hc_scompress,
138 .decompress = lz4hc_sdecompress,
139 .base = {
140 .cra_name = "lz4hc",
141 .cra_driver_name = "lz4hc-scomp",
142 .cra_module = THIS_MODULE,
143 }
144 };
145
lz4hc_mod_init(void)146 static int __init lz4hc_mod_init(void)
147 {
148 int ret;
149
150 ret = crypto_register_alg(&alg_lz4hc);
151 if (ret)
152 return ret;
153
154 ret = crypto_register_scomp(&scomp);
155 if (ret) {
156 crypto_unregister_alg(&alg_lz4hc);
157 return ret;
158 }
159
160 return ret;
161 }
162
lz4hc_mod_fini(void)163 static void __exit lz4hc_mod_fini(void)
164 {
165 crypto_unregister_alg(&alg_lz4hc);
166 crypto_unregister_scomp(&scomp);
167 }
168
169 module_init(lz4hc_mod_init);
170 module_exit(lz4hc_mod_fini);
171
172 MODULE_LICENSE("GPL");
173 MODULE_DESCRIPTION("LZ4HC Compression Algorithm");
174 MODULE_ALIAS_CRYPTO("lz4hc");
175
