1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22#include <linux/init.h>
23#include <linux/module.h>
24#include <linux/mm.h>
25#include <asm/byteorder.h>
26#include <asm/scatterlist.h>
27#include <linux/crypto.h>
28#include <linux/types.h>
29
30#define TEA_KEY_SIZE 16
31#define TEA_BLOCK_SIZE 8
32#define TEA_ROUNDS 32
33#define TEA_DELTA 0x9e3779b9
34
35#define XTEA_KEY_SIZE 16
36#define XTEA_BLOCK_SIZE 8
37#define XTEA_ROUNDS 32
38#define XTEA_DELTA 0x9e3779b9
39
40struct tea_ctx {
41 u32 KEY[4];
42};
43
44struct xtea_ctx {
45 u32 KEY[4];
46};
47
48static int tea_setkey(struct crypto_tfm *tfm, const u8 *in_key,
49 unsigned int key_len, u32 *flags)
50{
51 struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
52 const __le32 *key = (const __le32 *)in_key;
53
54 if (key_len != 16)
55 {
56 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
57 return -EINVAL;
58 }
59
60 ctx->KEY[0] = le32_to_cpu(key[0]);
61 ctx->KEY[1] = le32_to_cpu(key[1]);
62 ctx->KEY[2] = le32_to_cpu(key[2]);
63 ctx->KEY[3] = le32_to_cpu(key[3]);
64
65 return 0;
66
67}
68
69static void tea_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
70{
71 u32 y, z, n, sum = 0;
72 u32 k0, k1, k2, k3;
73 struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
74 const __le32 *in = (const __le32 *)src;
75 __le32 *out = (__le32 *)dst;
76
77 y = le32_to_cpu(in[0]);
78 z = le32_to_cpu(in[1]);
79
80 k0 = ctx->KEY[0];
81 k1 = ctx->KEY[1];
82 k2 = ctx->KEY[2];
83 k3 = ctx->KEY[3];
84
85 n = TEA_ROUNDS;
86
87 while (n-- > 0) {
88 sum += TEA_DELTA;
89 y += ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
90 z += ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
91 }
92
93 out[0] = cpu_to_le32(y);
94 out[1] = cpu_to_le32(z);
95}
96
97static void tea_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
98{
99 u32 y, z, n, sum;
100 u32 k0, k1, k2, k3;
101 struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
102 const __le32 *in = (const __le32 *)src;
103 __le32 *out = (__le32 *)dst;
104
105 y = le32_to_cpu(in[0]);
106 z = le32_to_cpu(in[1]);
107
108 k0 = ctx->KEY[0];
109 k1 = ctx->KEY[1];
110 k2 = ctx->KEY[2];
111 k3 = ctx->KEY[3];
112
113 sum = TEA_DELTA << 5;
114
115 n = TEA_ROUNDS;
116
117 while (n-- > 0) {
118 z -= ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
119 y -= ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
120 sum -= TEA_DELTA;
121 }
122
123 out[0] = cpu_to_le32(y);
124 out[1] = cpu_to_le32(z);
125}
126
127static int xtea_setkey(struct crypto_tfm *tfm, const u8 *in_key,
128 unsigned int key_len, u32 *flags)
129{
130 struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
131 const __le32 *key = (const __le32 *)in_key;
132
133 if (key_len != 16)
134 {
135 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
136 return -EINVAL;
137 }
138
139 ctx->KEY[0] = le32_to_cpu(key[0]);
140 ctx->KEY[1] = le32_to_cpu(key[1]);
141 ctx->KEY[2] = le32_to_cpu(key[2]);
142 ctx->KEY[3] = le32_to_cpu(key[3]);
143
144 return 0;
145
146}
147
148static void xtea_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
149{
150 u32 y, z, sum = 0;
151 u32 limit = XTEA_DELTA * XTEA_ROUNDS;
152 struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
153 const __le32 *in = (const __le32 *)src;
154 __le32 *out = (__le32 *)dst;
155
156 y = le32_to_cpu(in[0]);
157 z = le32_to_cpu(in[1]);
158
159 while (sum != limit) {
160 y += ((z << 4 ^ z >> 5) + z) ^ (sum + ctx->KEY[sum&3]);
161 sum += XTEA_DELTA;
162 z += ((y << 4 ^ y >> 5) + y) ^ (sum + ctx->KEY[sum>>11 &3]);
163 }
164
165 out[0] = cpu_to_le32(y);
166 out[1] = cpu_to_le32(z);
167}
168
169static void xtea_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
170{
171 u32 y, z, sum;
172 struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
173 const __le32 *in = (const __le32 *)src;
174 __le32 *out = (__le32 *)dst;
175
176 y = le32_to_cpu(in[0]);
177 z = le32_to_cpu(in[1]);
178
179 sum = XTEA_DELTA * XTEA_ROUNDS;
180
181 while (sum) {
182 z -= ((y << 4 ^ y >> 5) + y) ^ (sum + ctx->KEY[sum>>11 & 3]);
183 sum -= XTEA_DELTA;
184 y -= ((z << 4 ^ z >> 5) + z) ^ (sum + ctx->KEY[sum & 3]);
185 }
186
187 out[0] = cpu_to_le32(y);
188 out[1] = cpu_to_le32(z);
189}
190
191
192static void xeta_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
193{
194 u32 y, z, sum = 0;
195 u32 limit = XTEA_DELTA * XTEA_ROUNDS;
196 struct xtea_ctx *ctx = crypto_tfm_ctx(tfm);
197 const __le32 *in = (const __le32 *)src;
198 __le32 *out = (__le32 *)dst;
199
200 y = le32_to_cpu(in[0]);
201 z = le32_to_cpu(in[1]);
202
203 while (sum != limit) {
204 y += (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum&3];
205 sum += XTEA_DELTA;
206 z += (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 &3];
207 }
208
209 out[0] = cpu_to_le32(y);
210 out[1] = cpu_to_le32(z);
211}
212
213static void xeta_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
214{
215 u32 y, z, sum;
216 struct tea_ctx *ctx = crypto_tfm_ctx(tfm);
217 const __le32 *in = (const __le32 *)src;
218 __le32 *out = (__le32 *)dst;
219
220 y = le32_to_cpu(in[0]);
221 z = le32_to_cpu(in[1]);
222
223 sum = XTEA_DELTA * XTEA_ROUNDS;
224
225 while (sum) {
226 z -= (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 & 3];
227 sum -= XTEA_DELTA;
228 y -= (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum & 3];
229 }
230
231 out[0] = cpu_to_le32(y);
232 out[1] = cpu_to_le32(z);
233}
234
235static struct crypto_alg tea_alg = {
236 .cra_name = "tea",
237 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
238 .cra_blocksize = TEA_BLOCK_SIZE,
239 .cra_ctxsize = sizeof (struct tea_ctx),
240 .cra_alignmask = 3,
241 .cra_module = THIS_MODULE,
242 .cra_list = LIST_HEAD_INIT(tea_alg.cra_list),
243 .cra_u = { .cipher = {
244 .cia_min_keysize = TEA_KEY_SIZE,
245 .cia_max_keysize = TEA_KEY_SIZE,
246 .cia_setkey = tea_setkey,
247 .cia_encrypt = tea_encrypt,
248 .cia_decrypt = tea_decrypt } }
249};
250
251static struct crypto_alg xtea_alg = {
252 .cra_name = "xtea",
253 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
254 .cra_blocksize = XTEA_BLOCK_SIZE,
255 .cra_ctxsize = sizeof (struct xtea_ctx),
256 .cra_alignmask = 3,
257 .cra_module = THIS_MODULE,
258 .cra_list = LIST_HEAD_INIT(xtea_alg.cra_list),
259 .cra_u = { .cipher = {
260 .cia_min_keysize = XTEA_KEY_SIZE,
261 .cia_max_keysize = XTEA_KEY_SIZE,
262 .cia_setkey = xtea_setkey,
263 .cia_encrypt = xtea_encrypt,
264 .cia_decrypt = xtea_decrypt } }
265};
266
267static struct crypto_alg xeta_alg = {
268 .cra_name = "xeta",
269 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
270 .cra_blocksize = XTEA_BLOCK_SIZE,
271 .cra_ctxsize = sizeof (struct xtea_ctx),
272 .cra_alignmask = 3,
273 .cra_module = THIS_MODULE,
274 .cra_list = LIST_HEAD_INIT(xtea_alg.cra_list),
275 .cra_u = { .cipher = {
276 .cia_min_keysize = XTEA_KEY_SIZE,
277 .cia_max_keysize = XTEA_KEY_SIZE,
278 .cia_setkey = xtea_setkey,
279 .cia_encrypt = xeta_encrypt,
280 .cia_decrypt = xeta_decrypt } }
281};
282
283static int __init init(void)
284{
285 int ret = 0;
286
287 ret = crypto_register_alg(&tea_alg);
288 if (ret < 0)
289 goto out;
290
291 ret = crypto_register_alg(&xtea_alg);
292 if (ret < 0) {
293 crypto_unregister_alg(&tea_alg);
294 goto out;
295 }
296
297 ret = crypto_register_alg(&xeta_alg);
298 if (ret < 0) {
299 crypto_unregister_alg(&tea_alg);
300 crypto_unregister_alg(&xtea_alg);
301 goto out;
302 }
303
304out:
305 return ret;
306}
307
308static void __exit fini(void)
309{
310 crypto_unregister_alg(&tea_alg);
311 crypto_unregister_alg(&xtea_alg);
312 crypto_unregister_alg(&xeta_alg);
313}
314
315MODULE_ALIAS("xtea");
316MODULE_ALIAS("xeta");
317
318module_init(init);
319module_exit(fini);
320
321MODULE_LICENSE("GPL");
322MODULE_DESCRIPTION("TEA, XTEA & XETA Cryptographic Algorithms");
323
