Home Home > GIT Browse
summaryrefslogtreecommitdiff
blob: bc26dc942821c518819dc47f24aba7b97ad989ae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
/*
 * Cryptographic API for the 842 software compression algorithm.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * Copyright (C) IBM Corporation, 2011-2015
 *
 * Original Authors: Robert Jennings <rcj@linux.vnet.ibm.com>
 *                   Seth Jennings <sjenning@linux.vnet.ibm.com>
 *
 * Rewrite: Dan Streetman <ddstreet@ieee.org>
 *
 * This is the software implementation of compression and decompression using
 * the 842 format.  This uses the software 842 library at lib/842/ which is
 * only a reference implementation, and is very, very slow as compared to other
 * software compressors.  You probably do not want to use this software
 * compression.  If you have access to the PowerPC 842 compression hardware, you
 * want to use the 842 hardware compression interface, which is at:
 * drivers/crypto/nx/nx-842-crypto.c
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/crypto.h>
#include <linux/sw842.h>
#include <crypto/internal/scompress.h>

struct crypto842_ctx {
	void *wmem;	/* working memory for compress */
};

static void *crypto842_alloc_ctx(struct crypto_scomp *tfm)
{
	void *ctx;

	ctx = kmalloc(SW842_MEM_COMPRESS, GFP_KERNEL);
	if (!ctx)
		return ERR_PTR(-ENOMEM);

	return ctx;
}

static int crypto842_init(struct crypto_tfm *tfm)
{
	struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm);

	ctx->wmem = crypto842_alloc_ctx(NULL);
	if (IS_ERR(ctx->wmem))
		return -ENOMEM;

	return 0;
}

static void crypto842_free_ctx(struct crypto_scomp *tfm, void *ctx)
{
	kfree(ctx);
}

static void crypto842_exit(struct crypto_tfm *tfm)
{
	struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm);

	crypto842_free_ctx(NULL, ctx->wmem);
}

static int crypto842_compress(struct crypto_tfm *tfm,
			      const u8 *src, unsigned int slen,
			      u8 *dst, unsigned int *dlen)
{
	struct crypto842_ctx *ctx = crypto_tfm_ctx(tfm);

	return sw842_compress(src, slen, dst, dlen, ctx->wmem);
}

static int crypto842_scompress(struct crypto_scomp *tfm,
			       const u8 *src, unsigned int slen,
			       u8 *dst, unsigned int *dlen, void *ctx)
{
	return sw842_compress(src, slen, dst, dlen, ctx);
}

static int crypto842_decompress(struct crypto_tfm *tfm,
				const u8 *src, unsigned int slen,
				u8 *dst, unsigned int *dlen)
{
	return sw842_decompress(src, slen, dst, dlen);
}

static int crypto842_sdecompress(struct crypto_scomp *tfm,
				 const u8 *src, unsigned int slen,
				 u8 *dst, unsigned int *dlen, void *ctx)
{
	return sw842_decompress(src, slen, dst, dlen);
}

static struct crypto_alg alg = {
	.cra_name		= "842",
	.cra_driver_name	= "842-generic",
	.cra_priority		= 100,
	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
	.cra_ctxsize		= sizeof(struct crypto842_ctx),
	.cra_module		= THIS_MODULE,
	.cra_init		= crypto842_init,
	.cra_exit		= crypto842_exit,
	.cra_u			= { .compress = {
	.coa_compress		= crypto842_compress,
	.coa_decompress		= crypto842_decompress } }
};

static struct scomp_alg scomp = {
	.alloc_ctx		= crypto842_alloc_ctx,
	.free_ctx		= crypto842_free_ctx,
	.compress		= crypto842_scompress,
	.decompress		= crypto842_sdecompress,
	.base			= {
		.cra_name	= "842",
		.cra_driver_name = "842-scomp",
		.cra_priority	 = 100,
		.cra_module	 = THIS_MODULE,
	}
};

static int __init crypto842_mod_init(void)
{
	int ret;

	ret = crypto_register_alg(&alg);
	if (ret)
		return ret;

	ret = crypto_register_scomp(&scomp);
	if (ret) {
		crypto_unregister_alg(&alg);
		return ret;
	}

	return ret;
}
module_init(crypto842_mod_init);

static void __exit crypto842_mod_exit(void)
{
	crypto_unregister_alg(&alg);
	crypto_unregister_scomp(&scomp);
}
module_exit(crypto842_mod_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("842 Software Compression Algorithm");
MODULE_ALIAS_CRYPTO("842");
MODULE_ALIAS_CRYPTO("842-generic");
MODULE_AUTHOR("Dan Streetman <ddstreet@ieee.org>");