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");