1 files changed, 146 insertions, 0 deletions
diff --git a/xlators/cluster/dht/src/dht-hashfn-tea.c b/xlators/cluster/dht/src/dht-hashfn-tea.c
new file mode 100644
index 000000000..8437b4955
--- /dev/null
+++ b/xlators/cluster/dht/src/dht-hashfn-tea.c
@@ -0,0 +1,146 @@
+/*
+   Copyright (c) 2008 Z RESEARCH, Inc. <http://www.zresearch.com>
+   This file is part of GlusterFS.
+
+   GlusterFS 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 3 of the License,
+   or (at your option) any later version.
+
+   GlusterFS 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
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see
+   <http://www.gnu.org/licenses/>.
+*/
+
+
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+
+#define DELTA 0x9E3779B9
+#define FULLROUNDS 10		/* 32 is overkill, 16 is strong crypto */
+#define PARTROUNDS 6		/* 6 gets complete mixing */
+
+
+static int
+tearound (int rounds, uint32_t *array, uint32_t *h0, uint32_t *h1)
+{
+	uint32_t sum = 0;
+	int      n = 0;
+	uint32_t b0  = 0;
+	uint32_t b1  = 0;
+
+	b0 = *h0;
+	b1 = *h1;
+
+	n = rounds;
+
+	do {
+		sum += DELTA;
+		b0  += ((b1 << 4) + array[0])
+			^ (b1 + sum)
+			^ ((b1 >> 5) + array[1]);
+		b1  += ((b0 << 4) + array[2])
+			^ (b0 + sum)
+			^ ((b0 >> 5) + array[3]);
+	} while (--n);
+
+	*h0 += b0;
+	*h1 += b1;
+
+	return 0;
+}
+
+
+uint32_t
+__pad (int len)
+{
+	uint32_t pad = 0;
+
+	pad = (uint32_t) len | ((uint32_t) len << 8);
+	pad |= pad << 16;
+
+	return pad;
+}
+
+
+uint32_t
+dht_hashfn_tea (const char *msg, int len)
+{
+	uint32_t  h0 = 0x9464a485;
+	uint32_t  h1 = 0x542e1a94;
+	uint32_t  array[4];
+	uint32_t  pad = 0;
+	int       i = 0;
+	int       j = 0;
+	int       full_quads = 0;
+	int       full_words = 0;
+	int       full_bytes = 0;
+	uint32_t *intmsg = NULL;
+	int       word = 0;
+
+
+	intmsg = (uint32_t *) msg;
+	pad = __pad (len);
+
+	full_bytes   = len;
+	full_words   = len / 4;
+	full_quads   = len / 16;
+
+	for (i = 0; i < full_quads; i++) {
+		for (j = 0; j < 4; j++) {
+			word     = *intmsg;
+			array[j] = word;
+			intmsg++;
+			full_words--;
+			full_bytes -= 4;
+		}
+		tearound (PARTROUNDS, &array[0], &h0, &h1);
+	}
+
+	if ((len % 16) == 0) {
+		goto done;
+	}
+
+	for (j = 0; j < 4; j++) {
+		if (full_words) {
+			word     = *intmsg;
+			array[j] = word;
+			intmsg++;
+			full_words--;
+			full_bytes -= 4;
+		} else {
+			array[j] = pad;
+			while (full_bytes) {
+				array[j] <<= 8;
+				array[j] |= msg[len - full_bytes];
+				full_bytes--;
+			}
+		}
+	}
+	tearound (FULLROUNDS, &array[0], &h0, &h1);
+
+done:
+	return h0 ^ h1;
+}
+
+
+#if 0
+int
+main (int argc, char *argv[])
+{
+	int i = 0;
+	int hashval = 0;
+
+	for (i = 1; i < argc; i++) {
+		hashval = tea (argv[i], strlen (argv[i]));
+		printf ("%s: %x\n", argv[i], hashval);
+	}
+}
+#endif