1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Cryptographic API.
4 */
5
6#include <linux/init.h>
7#include <linux/module.h>
8#include <linux/crypto.h>
9#include <linux/vmalloc.h>
10#include <linux/mm.h>
11#include <linux/lzo.h>
12#include <crypto/internal/scompress.h>
13
14struct lzo_ctx {
15	void *lzo_comp_mem;
16};
17
18static void *lzo_alloc_ctx(struct crypto_scomp *tfm)
19{
20	void *ctx;
21
22	ctx = kvmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
23	if (!ctx)
24		return ERR_PTR(-ENOMEM);
25
26	return ctx;
27}
28
29static int lzo_init(struct crypto_tfm *tfm)
30{
31	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
32
33	ctx->lzo_comp_mem = lzo_alloc_ctx(NULL);
34	if (IS_ERR(ctx->lzo_comp_mem))
35		return -ENOMEM;
36
37	return 0;
38}
39
40static void lzo_free_ctx(struct crypto_scomp *tfm, void *ctx)
41{
42	kvfree(ctx);
43}
44
45static void lzo_exit(struct crypto_tfm *tfm)
46{
47	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
48
49	lzo_free_ctx(NULL, ctx->lzo_comp_mem);
50}
51
52static int __lzo_compress(const u8 *src, unsigned int slen,
53			  u8 *dst, unsigned int *dlen, void *ctx)
54{
55	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
56	int err;
57
58	err = lzo1x_1_compress(src, slen, dst, &tmp_len, ctx);
59
60	if (err != LZO_E_OK)
61		return -EINVAL;
62
63	*dlen = tmp_len;
64	return 0;
65}
66
67static int lzo_compress(struct crypto_tfm *tfm, const u8 *src,
68			unsigned int slen, u8 *dst, unsigned int *dlen)
69{
70	struct lzo_ctx *ctx = crypto_tfm_ctx(tfm);
71
72	return __lzo_compress(src, slen, dst, dlen, ctx->lzo_comp_mem);
73}
74
75static int lzo_scompress(struct crypto_scomp *tfm, const u8 *src,
76			 unsigned int slen, u8 *dst, unsigned int *dlen,
77			 void *ctx)
78{
79	return __lzo_compress(src, slen, dst, dlen, ctx);
80}
81
82static int __lzo_decompress(const u8 *src, unsigned int slen,
83			    u8 *dst, unsigned int *dlen)
84{
85	int err;
86	size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */
87
88	err = lzo1x_decompress_safe(src, slen, dst, &tmp_len);
89
90	if (err != LZO_E_OK)
91		return -EINVAL;
92
93	*dlen = tmp_len;
94	return 0;
95}
96
97static int lzo_decompress(struct crypto_tfm *tfm, const u8 *src,
98			  unsigned int slen, u8 *dst, unsigned int *dlen)
99{
100	return __lzo_decompress(src, slen, dst, dlen);
101}
102
103static int lzo_sdecompress(struct crypto_scomp *tfm, const u8 *src,
104			   unsigned int slen, u8 *dst, unsigned int *dlen,
105			   void *ctx)
106{
107	return __lzo_decompress(src, slen, dst, dlen);
108}
109
110static struct crypto_alg alg = {
111	.cra_name		= "lzo",
112	.cra_driver_name	= "lzo-generic",
113	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
114	.cra_ctxsize		= sizeof(struct lzo_ctx),
115	.cra_module		= THIS_MODULE,
116	.cra_init		= lzo_init,
117	.cra_exit		= lzo_exit,
118	.cra_u			= { .compress = {
119	.coa_compress		= lzo_compress,
120	.coa_decompress		= lzo_decompress } }
121};
122
123static struct scomp_alg scomp = {
124	.alloc_ctx		= lzo_alloc_ctx,
125	.free_ctx		= lzo_free_ctx,
126	.compress		= lzo_scompress,
127	.decompress		= lzo_sdecompress,
128	.base			= {
129		.cra_name	= "lzo",
130		.cra_driver_name = "lzo-scomp",
131		.cra_module	 = THIS_MODULE,
132	}
133};
134
135static int __init lzo_mod_init(void)
136{
137	int ret;
138
139	ret = crypto_register_alg(&alg);
140	if (ret)
141		return ret;
142
143	ret = crypto_register_scomp(&scomp);
144	if (ret) {
145		crypto_unregister_alg(&alg);
146		return ret;
147	}
148
149	return ret;
150}
151
152static void __exit lzo_mod_fini(void)
153{
154	crypto_unregister_alg(&alg);
155	crypto_unregister_scomp(&scomp);
156}
157
158subsys_initcall(lzo_mod_init);
159module_exit(lzo_mod_fini);
160
161MODULE_LICENSE("GPL");
162MODULE_DESCRIPTION("LZO Compression Algorithm");
163MODULE_ALIAS_CRYPTO("lzo");
164