1 | /* |
2 | * Cryptographic API. |
3 | * |
4 | * This program is free software; you can redistribute it and/or modify it |
5 | * under the terms of the GNU General Public License version 2 as published by |
6 | * the Free Software Foundation. |
7 | * |
8 | * This program is distributed in the hope that it will be useful, but WITHOUT |
9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
11 | * more details. |
12 | * |
13 | * You should have received a copy of the GNU General Public License along with |
14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
15 | * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
16 | * |
17 | */ |
18 | |
19 | #include <linux/init.h> |
20 | #include <linux/module.h> |
21 | #include <linux/crypto.h> |
22 | #include <linux/vmalloc.h> |
23 | #include <linux/mm.h> |
24 | #include <linux/lzo.h> |
25 | #include <crypto/internal/scompress.h> |
26 | |
27 | struct lzorle_ctx { |
28 | void *lzorle_comp_mem; |
29 | }; |
30 | |
31 | static void *lzorle_alloc_ctx(struct crypto_scomp *tfm) |
32 | { |
33 | void *ctx; |
34 | |
35 | ctx = kvmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); |
36 | if (!ctx) |
37 | return ERR_PTR(-ENOMEM); |
38 | |
39 | return ctx; |
40 | } |
41 | |
42 | static int lzorle_init(struct crypto_tfm *tfm) |
43 | { |
44 | struct lzorle_ctx *ctx = crypto_tfm_ctx(tfm); |
45 | |
46 | ctx->lzorle_comp_mem = lzorle_alloc_ctx(NULL); |
47 | if (IS_ERR(ctx->lzorle_comp_mem)) |
48 | return -ENOMEM; |
49 | |
50 | return 0; |
51 | } |
52 | |
53 | static void lzorle_free_ctx(struct crypto_scomp *tfm, void *ctx) |
54 | { |
55 | kvfree(ctx); |
56 | } |
57 | |
58 | static void lzorle_exit(struct crypto_tfm *tfm) |
59 | { |
60 | struct lzorle_ctx *ctx = crypto_tfm_ctx(tfm); |
61 | |
62 | lzorle_free_ctx(NULL, ctx->lzorle_comp_mem); |
63 | } |
64 | |
65 | static int __lzorle_compress(const u8 *src, unsigned int slen, |
66 | u8 *dst, unsigned int *dlen, void *ctx) |
67 | { |
68 | size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ |
69 | int err; |
70 | |
71 | err = lzorle1x_1_compress(src, slen, dst, &tmp_len, ctx); |
72 | |
73 | if (err != LZO_E_OK) |
74 | return -EINVAL; |
75 | |
76 | *dlen = tmp_len; |
77 | return 0; |
78 | } |
79 | |
80 | static int lzorle_compress(struct crypto_tfm *tfm, const u8 *src, |
81 | unsigned int slen, u8 *dst, unsigned int *dlen) |
82 | { |
83 | struct lzorle_ctx *ctx = crypto_tfm_ctx(tfm); |
84 | |
85 | return __lzorle_compress(src, slen, dst, dlen, ctx->lzorle_comp_mem); |
86 | } |
87 | |
88 | static int lzorle_scompress(struct crypto_scomp *tfm, const u8 *src, |
89 | unsigned int slen, u8 *dst, unsigned int *dlen, |
90 | void *ctx) |
91 | { |
92 | return __lzorle_compress(src, slen, dst, dlen, ctx); |
93 | } |
94 | |
95 | static int __lzorle_decompress(const u8 *src, unsigned int slen, |
96 | u8 *dst, unsigned int *dlen) |
97 | { |
98 | int err; |
99 | size_t tmp_len = *dlen; /* size_t(ulong) <-> uint on 64 bit */ |
100 | |
101 | err = lzo1x_decompress_safe(src, slen, dst, &tmp_len); |
102 | |
103 | if (err != LZO_E_OK) |
104 | return -EINVAL; |
105 | |
106 | *dlen = tmp_len; |
107 | return 0; |
108 | } |
109 | |
110 | static int lzorle_decompress(struct crypto_tfm *tfm, const u8 *src, |
111 | unsigned int slen, u8 *dst, unsigned int *dlen) |
112 | { |
113 | return __lzorle_decompress(src, slen, dst, dlen); |
114 | } |
115 | |
116 | static int lzorle_sdecompress(struct crypto_scomp *tfm, const u8 *src, |
117 | unsigned int slen, u8 *dst, unsigned int *dlen, |
118 | void *ctx) |
119 | { |
120 | return __lzorle_decompress(src, slen, dst, dlen); |
121 | } |
122 | |
123 | static struct crypto_alg alg = { |
124 | .cra_name = "lzo-rle" , |
125 | .cra_flags = CRYPTO_ALG_TYPE_COMPRESS, |
126 | .cra_ctxsize = sizeof(struct lzorle_ctx), |
127 | .cra_module = THIS_MODULE, |
128 | .cra_init = lzorle_init, |
129 | .cra_exit = lzorle_exit, |
130 | .cra_u = { .compress = { |
131 | .coa_compress = lzorle_compress, |
132 | .coa_decompress = lzorle_decompress } } |
133 | }; |
134 | |
135 | static struct scomp_alg scomp = { |
136 | .alloc_ctx = lzorle_alloc_ctx, |
137 | .free_ctx = lzorle_free_ctx, |
138 | .compress = lzorle_scompress, |
139 | .decompress = lzorle_sdecompress, |
140 | .base = { |
141 | .cra_name = "lzo-rle" , |
142 | .cra_driver_name = "lzo-rle-scomp" , |
143 | .cra_module = THIS_MODULE, |
144 | } |
145 | }; |
146 | |
147 | static int __init lzorle_mod_init(void) |
148 | { |
149 | int ret; |
150 | |
151 | ret = crypto_register_alg(&alg); |
152 | if (ret) |
153 | return ret; |
154 | |
155 | ret = crypto_register_scomp(&scomp); |
156 | if (ret) { |
157 | crypto_unregister_alg(&alg); |
158 | return ret; |
159 | } |
160 | |
161 | return ret; |
162 | } |
163 | |
164 | static void __exit lzorle_mod_fini(void) |
165 | { |
166 | crypto_unregister_alg(&alg); |
167 | crypto_unregister_scomp(&scomp); |
168 | } |
169 | |
170 | module_init(lzorle_mod_init); |
171 | module_exit(lzorle_mod_fini); |
172 | |
173 | MODULE_LICENSE("GPL" ); |
174 | MODULE_DESCRIPTION("LZO-RLE Compression Algorithm" ); |
175 | MODULE_ALIAS_CRYPTO("lzo-rle" ); |
176 | |