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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /crypto/tea.c
downloadlinux-sh-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
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.c248
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 @@
+/*
+ * Cryptographic API.
+ *
+ * TEA and Xtended TEA Algorithms
+ *
+ * The TEA and Xtended TEA algorithms were developed by David Wheeler
+ * and Roger Needham at the Computer Laboratory of Cambridge University.
+ *
+ * Copyright (c) 2004 Aaron Grothe ajgrothe@yahoo.com
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <asm/scatterlist.h>
+#include <linux/crypto.h>
+
+#define TEA_KEY_SIZE 16
+#define TEA_BLOCK_SIZE 8
+#define TEA_ROUNDS 32
+#define TEA_DELTA 0x9e3779b9
+
+#define XTEA_KEY_SIZE 16
+#define XTEA_BLOCK_SIZE 8
+#define XTEA_ROUNDS 32
+#define XTEA_DELTA 0x9e3779b9
+
+#define u32_in(x) le32_to_cpu(*(const __le32 *)(x))
+#define u32_out(to, from) (*(__le32 *)(to) = cpu_to_le32(from))
+
+struct tea_ctx {
+ u32 KEY[4];
+};
+
+struct xtea_ctx {
+ u32 KEY[4];
+};
+
+static int tea_setkey(void *ctx_arg, const u8 *in_key,
+ unsigned int key_len, u32 *flags)
+{
+
+ struct tea_ctx *ctx = ctx_arg;
+
+ if (key_len != 16)
+ {
+ *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+
+ ctx->KEY[0] = u32_in (in_key);
+ ctx->KEY[1] = u32_in (in_key + 4);
+ ctx->KEY[2] = u32_in (in_key + 8);
+ ctx->KEY[3] = u32_in (in_key + 12);
+
+ return 0;
+
+}
+
+static void tea_encrypt(void *ctx_arg, u8 *dst, const u8 *src)
+{
+ u32 y, z, n, sum = 0;
+ u32 k0, k1, k2, k3;
+
+ struct tea_ctx *ctx = ctx_arg;
+
+ y = u32_in (src);
+ z = u32_in (src + 4);
+
+ k0 = ctx->KEY[0];
+ k1 = ctx->KEY[1];
+ k2 = ctx->KEY[2];
+ k3 = ctx->KEY[3];
+
+ n = TEA_ROUNDS;
+
+ while (n-- > 0) {
+ sum += TEA_DELTA;
+ y += ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
+ z += ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
+ }
+
+ u32_out (dst, y);
+ u32_out (dst + 4, z);
+}
+
+static void tea_decrypt(void *ctx_arg, u8 *dst, const u8 *src)
+{
+ u32 y, z, n, sum;
+ u32 k0, k1, k2, k3;
+
+ struct tea_ctx *ctx = ctx_arg;
+
+ y = u32_in (src);
+ z = u32_in (src + 4);
+
+ k0 = ctx->KEY[0];
+ k1 = ctx->KEY[1];
+ k2 = ctx->KEY[2];
+ k3 = ctx->KEY[3];
+
+ sum = TEA_DELTA << 5;
+
+ n = TEA_ROUNDS;
+
+ while (n-- > 0) {
+ z -= ((y << 4) + k2) ^ (y + sum) ^ ((y >> 5) + k3);
+ y -= ((z << 4) + k0) ^ (z + sum) ^ ((z >> 5) + k1);
+ sum -= TEA_DELTA;
+ }
+
+ u32_out (dst, y);
+ u32_out (dst + 4, z);
+
+}
+
+static int xtea_setkey(void *ctx_arg, const u8 *in_key,
+ unsigned int key_len, u32 *flags)
+{
+
+ struct xtea_ctx *ctx = ctx_arg;
+
+ if (key_len != 16)
+ {
+ *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+
+ ctx->KEY[0] = u32_in (in_key);
+ ctx->KEY[1] = u32_in (in_key + 4);
+ ctx->KEY[2] = u32_in (in_key + 8);
+ ctx->KEY[3] = u32_in (in_key + 12);
+
+ return 0;
+
+}
+
+static void xtea_encrypt(void *ctx_arg, u8 *dst, const u8 *src)
+{
+
+ u32 y, z, sum = 0;
+ u32 limit = XTEA_DELTA * XTEA_ROUNDS;
+
+ struct xtea_ctx *ctx = ctx_arg;
+
+ y = u32_in (src);
+ z = u32_in (src + 4);
+
+ while (sum != limit) {
+ y += (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum&3];
+ sum += XTEA_DELTA;
+ z += (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 &3];
+ }
+
+ u32_out (dst, y);
+ u32_out (dst + 4, z);
+
+}
+
+static void xtea_decrypt(void *ctx_arg, u8 *dst, const u8 *src)
+{
+
+ u32 y, z, sum;
+ struct tea_ctx *ctx = ctx_arg;
+
+ y = u32_in (src);
+ z = u32_in (src + 4);
+
+ sum = XTEA_DELTA * XTEA_ROUNDS;
+
+ while (sum) {
+ z -= (y << 4 ^ y >> 5) + (y ^ sum) + ctx->KEY[sum>>11 & 3];
+ sum -= XTEA_DELTA;
+ y -= (z << 4 ^ z >> 5) + (z ^ sum) + ctx->KEY[sum & 3];
+ }
+
+ u32_out (dst, y);
+ u32_out (dst + 4, z);
+
+}
+
+static struct crypto_alg tea_alg = {
+ .cra_name = "tea",
+ .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
+ .cra_blocksize = TEA_BLOCK_SIZE,
+ .cra_ctxsize = sizeof (struct tea_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(tea_alg.cra_list),
+ .cra_u = { .cipher = {
+ .cia_min_keysize = TEA_KEY_SIZE,
+ .cia_max_keysize = TEA_KEY_SIZE,
+ .cia_setkey = tea_setkey,
+ .cia_encrypt = tea_encrypt,
+ .cia_decrypt = tea_decrypt } }
+};
+
+static struct crypto_alg xtea_alg = {
+ .cra_name = "xtea",
+ .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
+ .cra_blocksize = XTEA_BLOCK_SIZE,
+ .cra_ctxsize = sizeof (struct xtea_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(xtea_alg.cra_list),
+ .cra_u = { .cipher = {
+ .cia_min_keysize = XTEA_KEY_SIZE,
+ .cia_max_keysize = XTEA_KEY_SIZE,
+ .cia_setkey = xtea_setkey,
+ .cia_encrypt = xtea_encrypt,
+ .cia_decrypt = xtea_decrypt } }
+};
+
+static int __init init(void)
+{
+ int ret = 0;
+
+ ret = crypto_register_alg(&tea_alg);
+ if (ret < 0)
+ goto out;
+
+ ret = crypto_register_alg(&xtea_alg);
+ if (ret < 0) {
+ crypto_unregister_alg(&tea_alg);
+ goto out;
+ }
+
+out:
+ return ret;
+}
+
+static void __exit fini(void)
+{
+ crypto_unregister_alg(&tea_alg);
+ crypto_unregister_alg(&xtea_alg);
+}
+
+MODULE_ALIAS("xtea");
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("TEA & XTEA Cryptographic Algorithms");