summaryrefslogtreecommitdiff
path: root/target/linux/generic/patches-3.12/540-crypto-xz-decompression-support.patch
blob: 6e26648e3b67d2602c13898bf17a23e9916156e4 (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
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -1352,6 +1352,13 @@ config CRYPTO_LZ4HC
 	help
 	  This is the LZ4 high compression mode algorithm.
 
+config CRYPTO_XZ
+	tristate "XZ compression algorithm"
+	select CRYPTO_ALGAPI
+	select XZ_DEC
+	help
+	  This is the XZ algorithm. Only decompression is supported for now.
+
 comment "Random Number Generation"
 
 config CRYPTO_ANSI_CPRNG
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -88,6 +88,7 @@ obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.
 obj-$(CONFIG_CRYPTO_LZO) += lzo.o
 obj-$(CONFIG_CRYPTO_LZ4) += lz4.o
 obj-$(CONFIG_CRYPTO_LZ4HC) += lz4hc.o
+obj-$(CONFIG_CRYPTO_XZ) += xz.o
 obj-$(CONFIG_CRYPTO_842) += 842.o
 obj-$(CONFIG_CRYPTO_RNG2) += rng.o
 obj-$(CONFIG_CRYPTO_RNG2) += krng.o
--- /dev/null
+++ b/crypto/xz.c
@@ -0,0 +1,117 @@
+/*
+ * Cryptographic API.
+ *
+ * XZ decompression support.
+ *
+ * Copyright (c) 2012 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/xz.h>
+#include <linux/interrupt.h>
+#include <linux/mm.h>
+#include <linux/net.h>
+
+struct xz_comp_ctx {
+	struct xz_dec	*decomp_state;
+	struct xz_buf	decomp_buf;
+};
+
+static int crypto_xz_decomp_init(struct xz_comp_ctx *ctx)
+{
+	ctx->decomp_state = xz_dec_init(XZ_SINGLE, 0);
+	if (!ctx->decomp_state)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void crypto_xz_decomp_exit(struct xz_comp_ctx *ctx)
+{
+	xz_dec_end(ctx->decomp_state);
+}
+
+static int crypto_xz_init(struct crypto_tfm *tfm)
+{
+	struct xz_comp_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	return crypto_xz_decomp_init(ctx);
+}
+
+static void crypto_xz_exit(struct crypto_tfm *tfm)
+{
+	struct xz_comp_ctx *ctx = crypto_tfm_ctx(tfm);
+
+	crypto_xz_decomp_exit(ctx);
+}
+
+static int crypto_xz_compress(struct crypto_tfm *tfm, const u8 *src,
+			      unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+	return -EOPNOTSUPP;
+}
+
+static int crypto_xz_decompress(struct crypto_tfm *tfm, const u8 *src,
+				unsigned int slen, u8 *dst, unsigned int *dlen)
+{
+	struct xz_comp_ctx *dctx = crypto_tfm_ctx(tfm);
+	struct xz_buf *xz_buf = &dctx->decomp_buf;
+	int ret;
+
+	memset(xz_buf, '\0', sizeof(struct xz_buf));
+
+	xz_buf->in = (u8 *) src;
+	xz_buf->in_pos = 0;
+	xz_buf->in_size = slen;
+	xz_buf->out = (u8 *) dst;
+	xz_buf->out_pos = 0;
+	xz_buf->out_size = *dlen;
+
+	ret = xz_dec_run(dctx->decomp_state, xz_buf);
+	if (ret != XZ_STREAM_END) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	*dlen = xz_buf->out_pos;
+	ret = 0;
+
+out:
+	return ret;
+}
+
+static struct crypto_alg crypto_xz_alg = {
+	.cra_name		= "xz",
+	.cra_flags		= CRYPTO_ALG_TYPE_COMPRESS,
+	.cra_ctxsize		= sizeof(struct xz_comp_ctx),
+	.cra_module		= THIS_MODULE,
+	.cra_list		= LIST_HEAD_INIT(crypto_xz_alg.cra_list),
+	.cra_init		= crypto_xz_init,
+	.cra_exit		= crypto_xz_exit,
+	.cra_u			= { .compress = {
+	.coa_compress 		= crypto_xz_compress,
+	.coa_decompress  	= crypto_xz_decompress } }
+};
+
+static int __init crypto_xz_mod_init(void)
+{
+	return crypto_register_alg(&crypto_xz_alg);
+}
+
+static void __exit crypto_xz_mod_exit(void)
+{
+	crypto_unregister_alg(&crypto_xz_alg);
+}
+
+module_init(crypto_xz_mod_init);
+module_exit(crypto_xz_mod_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Crypto XZ decompression support");
+MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");