--- /dev/null
+/* -*-c-*-
+ *
+ * The Tiny Encryption Algorithm
+ *
+ * (c) 2000 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <mLib/bits.h>
+
+#include "blkc.h"
+#include "gcipher.h"
+#include "paranoia.h"
+#include "tea.h"
+
+/*----- Global variables --------------------------------------------------*/
+
+const octet tea_keysz[] = { KSZ_RANGE, TEA_KEYSZ, 0, 16, 1 };
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @tea_init@ --- *
+ *
+ * Arguments: @tea_ctx *k@ = pointer to key block
+ * @const void *buf@ = pointer to key buffer
+ * @size_t sz@ = size of key material
+ *
+ * Returns: ---
+ *
+ * Use: Initializes a TEA key buffer. The key buffer must be 16
+ * bytes long.
+ */
+
+void tea_init(tea_ctx *k, const void *buf, size_t sz)
+{
+ octet kb[16];
+ const octet *p;
+
+ KSZ_ASSERT(tea, sz);
+ if (sz >= sizeof(kb))
+ p = buf;
+ else {
+ memcpy(kb, buf, sz);
+ memset(kb + sz, 0, sizeof(kb) - sz);
+ p = kb;
+ }
+
+ k->ka = LOAD32(p + 0); k->kb = LOAD32(p + 4);
+ k->kc = LOAD32(p + 8); k->kd = LOAD32(p + 12);
+ k->r = 32;
+
+ if (p == kb)
+ BURN(kb);
+}
+
+/* --- @tea_eblk@, @tea_dblk@ --- *
+ *
+ * Arguments: @const tea_ctx *k@ = pointer to key block
+ * @const uint32 s[2]@ = pointer to source block
+ * @uint32 d[2]@ = pointer to teatination block
+ *
+ * Returns: ---
+ *
+ * Use: Low-level block encryption and decryption.
+ */
+
+#define DELTA 0x9e3779b9
+
+void tea_eblk(const tea_ctx *k, const uint32 *s, uint32 *d)
+{
+ uint32 y = s[0], z = s[1];
+ uint32 ka = k->ka, kb = k->kb, kc = k->kc, kd = k->kd;
+ uint32 n = 0;
+ unsigned i;
+
+ for (i = 0; i < k->r; i++) {
+ n += DELTA;
+ y = U32(y + (((z << 4) + ka) ^ (z + n) ^ ((z >> 5) + kb)));
+ z = U32(z + (((y << 4) + kc) ^ (y + n) ^ ((y >> 5) + kd)));
+ }
+ d[0] = y; d[1] = z;
+}
+
+void tea_dblk(const tea_ctx *k, const uint32 *s, uint32 *d)
+{
+ uint32 y = s[0], z = s[1];
+ uint32 ka = k->ka, kb = k->kb, kc = k->kc, kd = k->kd;
+ uint32 n = DELTA * k->r;
+ unsigned i;
+
+ for (i = 0; i < k->r; i++) {
+ z = U32(z - (((y << 4) + kc) ^ (y + n) ^ ((y >> 5) + kd)));
+ y = U32(y - (((z << 4) + ka) ^ (z + n) ^ ((z >> 5) + kb)));
+ n -= DELTA;
+ }
+ d[0] = y; d[1] = z;
+}
+
+BLKC_TEST(TEA, tea)
+
+/*----- That's all, folks -------------------------------------------------*/