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 <linux/init.h>
8 #include <linux/module.h>
9 #include <linux/crypto.h>
10 #include <linux/vmalloc.h>
11 #include <linux/lz4.h>
12 #include <crypto/internal/scompress.h>
13 
14 struct lz4hc_ctx {
15 	void *lz4hc_comp_mem;
16 };
17 
lz4hc_alloc_ctx(struct crypto_scomp * tfm)18 static void *lz4hc_alloc_ctx(struct crypto_scomp *tfm)
19 {
20 	void *ctx;
21 
22 	ctx = vmalloc(LZ4HC_MEM_COMPRESS);
23 	if (!ctx)
24 		return ERR_PTR(-ENOMEM);
25 
26 	return ctx;
27 }
28 
lz4hc_init(struct crypto_tfm * tfm)29 static int lz4hc_init(struct crypto_tfm *tfm)
30 {
31 	struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
32 
33 	ctx->lz4hc_comp_mem = lz4hc_alloc_ctx(NULL);
34 	if (IS_ERR(ctx->lz4hc_comp_mem))
35 		return -ENOMEM;
36 
37 	return 0;
38 }
39 
lz4hc_free_ctx(struct crypto_scomp * tfm,void * ctx)40 static void lz4hc_free_ctx(struct crypto_scomp *tfm, void *ctx)
41 {
42 	vfree(ctx);
43 }
44 
lz4hc_exit(struct crypto_tfm * tfm)45 static void lz4hc_exit(struct crypto_tfm *tfm)
46 {
47 	struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
48 
49 	lz4hc_free_ctx(NULL, ctx->lz4hc_comp_mem);
50 }
51 
__lz4hc_compress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)52 static int __lz4hc_compress_crypto(const u8 *src, unsigned int slen,
53 				   u8 *dst, unsigned int *dlen, void *ctx)
54 {
55 	int out_len = LZ4_compress_HC(src, dst, slen,
56 		*dlen, LZ4HC_DEFAULT_CLEVEL, ctx);
57 
58 	if (!out_len)
59 		return -EINVAL;
60 
61 	*dlen = out_len;
62 	return 0;
63 }
64 
lz4hc_scompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)65 static int lz4hc_scompress(struct crypto_scomp *tfm, const u8 *src,
66 			   unsigned int slen, u8 *dst, unsigned int *dlen,
67 			   void *ctx)
68 {
69 	return __lz4hc_compress_crypto(src, slen, dst, dlen, ctx);
70 }
71 
lz4hc_compress_crypto(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)72 static int lz4hc_compress_crypto(struct crypto_tfm *tfm, const u8 *src,
73 				 unsigned int slen, u8 *dst,
74 				 unsigned int *dlen)
75 {
76 	struct lz4hc_ctx *ctx = crypto_tfm_ctx(tfm);
77 
78 	return __lz4hc_compress_crypto(src, slen, dst, dlen,
79 					ctx->lz4hc_comp_mem);
80 }
81 
__lz4hc_decompress_crypto(const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)82 static int __lz4hc_decompress_crypto(const u8 *src, unsigned int slen,
83 				     u8 *dst, unsigned int *dlen, void *ctx)
84 {
85 	int out_len = LZ4_decompress_safe(src, dst, slen, *dlen);
86 
87 	if (out_len < 0)
88 		return -EINVAL;
89 
90 	*dlen = out_len;
91 	return 0;
92 }
93 
lz4hc_sdecompress(struct crypto_scomp * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen,void * ctx)94 static int lz4hc_sdecompress(struct crypto_scomp *tfm, const u8 *src,
95 			     unsigned int slen, u8 *dst, unsigned int *dlen,
96 			     void *ctx)
97 {
98 	return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL);
99 }
100 
lz4hc_decompress_crypto(struct crypto_tfm * tfm,const u8 * src,unsigned int slen,u8 * dst,unsigned int * dlen)101 static int lz4hc_decompress_crypto(struct crypto_tfm *tfm, const u8 *src,
102 				   unsigned int slen, u8 *dst,
103 				   unsigned int *dlen)
104 {
105 	return __lz4hc_decompress_crypto(src, slen, dst, dlen, NULL);
106 }
107 
108 static struct crypto_alg alg_lz4hc = {
109 	.cra_name		= "lz4hc",
110 	.cra_driver_name	= "lz4hc-generic",
111 	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
112 	.cra_ctxsize		= sizeof(struct lz4hc_ctx),
113 	.cra_module		= THIS_MODULE,
114 	.cra_init		= lz4hc_init,
115 	.cra_exit		= lz4hc_exit,
116 	.cra_u			= { .compress = {
117 	.coa_compress		= lz4hc_compress_crypto,
118 	.coa_decompress		= lz4hc_decompress_crypto } }
119 };
120 
121 static struct scomp_alg scomp = {
122 	.alloc_ctx		= lz4hc_alloc_ctx,
123 	.free_ctx		= lz4hc_free_ctx,
124 	.compress		= lz4hc_scompress,
125 	.decompress		= lz4hc_sdecompress,
126 	.base			= {
127 		.cra_name	= "lz4hc",
128 		.cra_driver_name = "lz4hc-scomp",
129 		.cra_module	 = THIS_MODULE,
130 	}
131 };
132 
lz4hc_mod_init(void)133 static int __init lz4hc_mod_init(void)
134 {
135 	int ret;
136 
137 	ret = crypto_register_alg(&alg_lz4hc);
138 	if (ret)
139 		return ret;
140 
141 	ret = crypto_register_scomp(&scomp);
142 	if (ret) {
143 		crypto_unregister_alg(&alg_lz4hc);
144 		return ret;
145 	}
146 
147 	return ret;
148 }
149 
lz4hc_mod_fini(void)150 static void __exit lz4hc_mod_fini(void)
151 {
152 	crypto_unregister_alg(&alg_lz4hc);
153 	crypto_unregister_scomp(&scomp);
154 }
155 
156 subsys_initcall(lz4hc_mod_init);
157 module_exit(lz4hc_mod_fini);
158 
159 MODULE_LICENSE("GPL");
160 MODULE_DESCRIPTION("LZ4HC Compression Algorithm");
161 MODULE_ALIAS_CRYPTO("lz4hc");
162