diff options
| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
|---|---|---|
| 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-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 00000000000..03c23cbd3af --- /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"); | ||
