1263198Srwatson/*- 2263198Srwatson * Copyright (c) 2010 David Malone <dwmalone@FreeBSD.org> 3263198Srwatson * All rights reserved. 4263198Srwatson * 5263198Srwatson * Redistribution and use in source and binary forms, with or without 6263198Srwatson * modification, are permitted provided that the following conditions 7263198Srwatson * are met: 8263198Srwatson * 1. Redistributions of source code must retain the above copyright 9263198Srwatson * notice, this list of conditions and the following disclaimer. 10263198Srwatson * 2. Redistributions in binary form must reproduce the above copyright 11263198Srwatson * notice, this list of conditions and the following disclaimer in the 12263198Srwatson * documentation and/or other materials provided with the distribution. 13263198Srwatson * 14263198Srwatson * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15263198Srwatson * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16263198Srwatson * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17263198Srwatson * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18263198Srwatson * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19263198Srwatson * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20263198Srwatson * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21263198Srwatson * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22263198Srwatson * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23263198Srwatson * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24263198Srwatson * SUCH DAMAGE. 25263198Srwatson */ 26263198Srwatson 27263198Srwatson#include <sys/cdefs.h> 28263198Srwatson__FBSDID("$FreeBSD$"); 29263198Srwatson 30263198Srwatson#include <sys/types.h> 31263198Srwatson 32277331Sadrian#include <net/rss_config.h> 33277331Sadrian#include <net/toeplitz.h> 34263198Srwatson 35263198Srwatson#include <sys/systm.h> 36263198Srwatson 37263198Srwatsonuint32_t 38263198Srwatsontoeplitz_hash(u_int keylen, const uint8_t *key, u_int datalen, 39263198Srwatson const uint8_t *data) 40263198Srwatson{ 41263198Srwatson uint32_t hash = 0, v; 42263198Srwatson u_int i, b; 43263198Srwatson 44263198Srwatson /* XXXRW: Perhaps an assertion about key length vs. data length? */ 45263198Srwatson 46263198Srwatson v = (key[0]<<24) + (key[1]<<16) + (key[2] <<8) + key[3]; 47263198Srwatson for (i = 0; i < datalen; i++) { 48263198Srwatson for (b = 0; b < 8; b++) { 49263198Srwatson if (data[i] & (1<<(7-b))) 50263198Srwatson hash ^= v; 51263198Srwatson v <<= 1; 52263198Srwatson if ((i + 4) < RSS_KEYSIZE && 53263198Srwatson (key[i+4] & (1<<(7-b)))) 54263198Srwatson v |= 1; 55263198Srwatson } 56263198Srwatson } 57263198Srwatson return (hash); 58263198Srwatson} 59