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
 14struct lz4hc_ctx {
 15	void *lz4hc_comp_mem;
 16};
 17
 18static 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
 29static 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
 40static void lz4hc_free_ctx(struct crypto_scomp *tfm, void *ctx)
 41{
 42	vfree(ctx);
 43}
 44
 45static 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
 52static 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
 65static 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
 72static 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
 82static 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
 94static 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
101static 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
108static 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
121static 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
133static 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
150static void __exit lz4hc_mod_fini(void)
151{
152	crypto_unregister_alg(&alg_lz4hc);
153	crypto_unregister_scomp(&scomp);
154}
155
156subsys_initcall(lz4hc_mod_init);
157module_exit(lz4hc_mod_fini);
158
159MODULE_LICENSE("GPL");
160MODULE_DESCRIPTION("LZ4HC Compression Algorithm");
161MODULE_ALIAS_CRYPTO("lz4hc");