diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /crypto/tea.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'crypto/tea.c')
-rw-r--r-- | crypto/tea.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/crypto/tea.c b/crypto/tea.c new file mode 100644 index 000000000000..03c23cbd3afa --- /dev/null +++ b/crypto/tea.c | |||
@@ -0,0 +1,248 @@ | |||
1 | /* | ||
2 | * Cryptographic API. | ||
3 | * | ||
4 | * TEA and Xtended TEA Algorithms | ||
5 | * | ||
6 | * The TEA and Xtended TEA algorithms were developed by David Wheeler | ||
7 | * and Roger Needham at the Computer Laboratory of Cambridge University. | ||
8 | * | ||
9 | * Copyright (c) 2004 Aaron Grothe ajgrothe@yahoo.com | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or modify | ||
12 | * it under the terms of the GNU General Public License as published by | ||
13 | * the Free Software Foundation; either version 2 of the License, or | ||
14 | * (at your option) any later version. | ||
15 | * | ||
16 | */ | ||
17 | |||
18 | #include <linux/init.h> | ||
19 | #include <linux/module.h> | ||
20 | #include <linux/mm.h> | ||
21 | #include <asm/scatterlist.h> | ||
22 | #include <linux/crypto.h> | ||
23 | |||
24 | #define TEA_KEY_SIZE 16 | ||
25 | #define TEA_BLOCK_SIZE 8 | ||
26 | #define TEA_ROUNDS 32 | ||
27 | #define TEA_DELTA 0x9e3779b9 | ||
28 | |||
29 | #define XTEA_KEY_SIZE 16 | ||
30 | #define XTEA_BLOCK_SIZE 8 | ||
31 | #define XTEA_ROUNDS 32 | ||
32 | #define XTEA_DELTA 0x9e3779b9 | ||
33 | |||
34 | #define u32_in(x) le32_to_cpu(*(const __le32 *)(x)) | ||
35 | #define u32_out(to, from) (*(__le32 *)(to) = cpu_to_le32(from)) | ||
36 | |||
37 | struct tea_ctx { | ||
38 | u32 KEY[4]; | ||
39 | }; | ||
40 | |||
41 | struct xtea_ctx { | ||
42 | u32 KEY[4]; | ||
43 | }; | ||
44 | |||
45 | static int tea_setkey(void *ctx_arg, const u8 *in_key, | ||
46 | unsigned int key_len, u32 *flags) | ||
47 | { | ||
48 | |||
49 | struct tea_ctx *ctx = ctx_arg; | ||
50 | |||
51 | if (key_len != 16) | ||
52 | { | ||
53 | *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; | ||
54 | return -EINVAL; | ||
55 | } | ||
56 | |||
57 | ctx->KEY[0] = u32_in (in_key); | ||
58 | ctx->KEY[1] = u32_in (in_key + 4); | ||
59 | ctx->KEY[2] = u32_in (in_key + 8); | ||
60 | ctx->KEY[3] = u32_in (in_key + 12); | ||
61 | |||
62 | return 0; | ||
63 | |||
64 | } | ||
65 | |||
66 | static void tea_encrypt(void *ctx_arg, u8 *dst, const u8 *src) | ||
67 | { | ||
68 | u32 y, z, n, sum = 0; | ||
69 | u32 k0, k1, k2, k3; | ||
70 | |||
71 | struct tea_ctx *ctx = ctx_arg; | ||
72 | |||
73 | y = u32_in (src); | ||
74 | z = u32_in (src + 4); | ||
75 | |||
76 | k0 = ctx->KEY[0]; | ||
77 | k1 = ctx->KEY[1]; | ||
78 | k2 = ctx->KEY[2]; | ||
79 | k3 = ctx->KEY[3]; | ||
80 | |||
81 | n = TEA_ROUNDS; | ||
82 | |||
83 | while (n-- > 0) { | ||
84 | sum += TEA_DELTA; | ||
85 | y += ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1); | ||
86 | z += ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3); | ||
87 | } | ||
88 | |||
89 | u32_out (dst, y); | ||
90 | u32_out (dst + 4, z); | ||
91 | } | ||
92 | |||
93 | static void tea_decrypt(void *ctx_arg, u8 *dst, const u8 *src) | ||
94 | { | ||
95 | u32 y, z, n, sum; | ||
96 | u32 k0, k1, k2, k3; | ||
97 | |||
98 | struct tea_ctx *ctx = ctx_arg; | ||
99 | |||
100 | y = u32_in (src); | ||
101 | z = u32_in (src + 4); | ||
102 | |||
103 | k0 = ctx->KEY[0]; | ||
104 | k1 = ctx->KEY[1]; | ||
105 | k2 = ctx->KEY[2]; | ||
106 | k3 = ctx->KEY[3]; | ||
107 | |||
108 | sum = TEA_DELTA << 5; | ||
109 | |||
110 | n = TEA_ROUNDS; | ||
111 | |||
112 | while (n-- > 0) { | ||
113 | z -= ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3); | ||
114 | y -= ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1); | ||
115 | sum -= TEA_DELTA; | ||
116 | } | ||
117 | |||
118 | u32_out (dst, y); | ||
119 | u32_out (dst + 4, z); | ||
120 | |||
121 | } | ||
122 | |||
123 | static int xtea_setkey(void *ctx_arg, const u8 *in_key, | ||
124 | unsigned int key_len, u32 *flags) | ||
125 | { | ||
126 | |||
127 | struct xtea_ctx *ctx = ctx_arg; | ||
128 | |||
129 | if (key_len != 16) | ||
130 | { | ||
131 | *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; | ||
132 | return -EINVAL; | ||
133 | } | ||
134 | |||
135 | ctx->KEY[0] = u32_in (in_key); | ||
136 | ctx->KEY[1] = u32_in (in_key + 4); | ||
137 | ctx->KEY[2] = u32_in (in_key + 8); | ||
138 | ctx->KEY[3] = u32_in (in_key + 12); | ||
139 | |||
140 | return 0; | ||
141 | |||
142 | } | ||
143 | |||
144 | static void xtea_encrypt(void *ctx_arg, u8 *dst, const u8 *src) | ||
145 | { | ||
146 | |||
147 | u32 y, z, sum = 0; | ||
148 | u32 limit = XTEA_DELTA * XTEA_ROUNDS; | ||
149 | |||
150 | struct xtea_ctx *ctx = ctx_arg; | ||
151 | |||
152 | y = u32_in (src); | ||
153 | z = u32_in (src + 4); | ||
154 | |||
155 | while (sum != limit) { | ||
156 | y += (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum&3]; | ||
157 | sum += XTEA_DELTA; | ||
158 | z += (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 &3]; | ||
159 | } | ||
160 | |||
161 | u32_out (dst, y); | ||
162 | u32_out (dst + 4, z); | ||
163 | |||
164 | } | ||
165 | |||
166 | static void xtea_decrypt(void *ctx_arg, u8 *dst, const u8 *src) | ||
167 | { | ||
168 | |||
169 | u32 y, z, sum; | ||
170 | struct tea_ctx *ctx = ctx_arg; | ||
171 | |||
172 | y = u32_in (src); | ||
173 | z = u32_in (src + 4); | ||
174 | |||
175 | sum = XTEA_DELTA * XTEA_ROUNDS; | ||
176 | |||
177 | while (sum) { | ||
178 | z -= (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 & 3]; | ||
179 | sum -= XTEA_DELTA; | ||
180 | y -= (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum & 3]; | ||
181 | } | ||
182 | |||
183 | u32_out (dst, y); | ||
184 | u32_out (dst + 4, z); | ||
185 | |||
186 | } | ||
187 | |||
188 | static struct crypto_alg tea_alg = { | ||
189 | .cra_name = "tea", | ||
190 | .cra_flags = CRYPTO_ALG_TYPE_CIPHER, | ||
191 | .cra_blocksize = TEA_BLOCK_SIZE, | ||
192 | .cra_ctxsize = sizeof (struct tea_ctx), | ||
193 | .cra_module = THIS_MODULE, | ||
194 | .cra_list = LIST_HEAD_INIT(tea_alg.cra_list), | ||
195 | .cra_u = { .cipher = { | ||
196 | .cia_min_keysize = TEA_KEY_SIZE, | ||
197 | .cia_max_keysize = TEA_KEY_SIZE, | ||
198 | .cia_setkey = tea_setkey, | ||
199 | .cia_encrypt = tea_encrypt, | ||
200 | .cia_decrypt = tea_decrypt } } | ||
201 | }; | ||
202 | |||
203 | static struct crypto_alg xtea_alg = { | ||
204 | .cra_name = "xtea", | ||
205 | .cra_flags = CRYPTO_ALG_TYPE_CIPHER, | ||
206 | .cra_blocksize = XTEA_BLOCK_SIZE, | ||
207 | .cra_ctxsize = sizeof (struct xtea_ctx), | ||
208 | .cra_module = THIS_MODULE, | ||
209 | .cra_list = LIST_HEAD_INIT(xtea_alg.cra_list), | ||
210 | .cra_u = { .cipher = { | ||
211 | .cia_min_keysize = XTEA_KEY_SIZE, | ||
212 | .cia_max_keysize = XTEA_KEY_SIZE, | ||
213 | .cia_setkey = xtea_setkey, | ||
214 | .cia_encrypt = xtea_encrypt, | ||
215 | .cia_decrypt = xtea_decrypt } } | ||
216 | }; | ||
217 | |||
218 | static int __init init(void) | ||
219 | { | ||
220 | int ret = 0; | ||
221 | |||
222 | ret = crypto_register_alg(&tea_alg); | ||
223 | if (ret < 0) | ||
224 | goto out; | ||
225 | |||
226 | ret = crypto_register_alg(&xtea_alg); | ||
227 | if (ret < 0) { | ||
228 | crypto_unregister_alg(&tea_alg); | ||
229 | goto out; | ||
230 | } | ||
231 | |||
232 | out: | ||
233 | return ret; | ||
234 | } | ||
235 | |||
236 | static void __exit fini(void) | ||
237 | { | ||
238 | crypto_unregister_alg(&tea_alg); | ||
239 | crypto_unregister_alg(&xtea_alg); | ||
240 | } | ||
241 | |||
242 | MODULE_ALIAS("xtea"); | ||
243 | |||
244 | module_init(init); | ||
245 | module_exit(fini); | ||
246 | |||
247 | MODULE_LICENSE("GPL"); | ||
248 | MODULE_DESCRIPTION("TEA & XTEA Cryptographic Algorithms"); | ||