aboutsummaryrefslogtreecommitdiff
path: root/sys/net/toeplitz.c
diff options
context:
space:
mode:
Diffstat (limited to 'sys/net/toeplitz.c')
-rw-r--r--sys/net/toeplitz.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/sys/net/toeplitz.c b/sys/net/toeplitz.c
new file mode 100644
index 000000000000..c57c133f044e
--- /dev/null
+++ b/sys/net/toeplitz.c
@@ -0,0 +1,55 @@
+/*-
+ * Copyright (c) 2010 David Malone <dwmalone@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/types.h>
+
+#include <net/rss_config.h>
+#include <net/toeplitz.h>
+
+#include <sys/systm.h>
+
+uint32_t
+toeplitz_hash(u_int keylen, const uint8_t *key, u_int datalen,
+ const uint8_t *data)
+{
+ uint32_t hash = 0, v;
+ u_int i, b;
+
+ /* XXXRW: Perhaps an assertion about key length vs. data length? */
+
+ v = (key[0]<<24) + (key[1]<<16) + (key[2] <<8) + key[3];
+ for (i = 0; i < datalen; i++) {
+ for (b = 0; b < 8; b++) {
+ if (data[i] & (1<<(7-b)))
+ hash ^= v;
+ v <<= 1;
+ if ((i + 4) < RSS_KEYSIZE &&
+ (key[i+4] & (1<<(7-b))))
+ v |= 1;
+ }
+ }
+ return (hash);
+}