1*b2bdc62aSAdrian Chadd /*- 2*b2bdc62aSAdrian Chadd * Copyright (c) 2010 David Malone <dwmalone@FreeBSD.org> 3*b2bdc62aSAdrian Chadd * All rights reserved. 4*b2bdc62aSAdrian Chadd * 5*b2bdc62aSAdrian Chadd * Redistribution and use in source and binary forms, with or without 6*b2bdc62aSAdrian Chadd * modification, are permitted provided that the following conditions 7*b2bdc62aSAdrian Chadd * are met: 8*b2bdc62aSAdrian Chadd * 1. Redistributions of source code must retain the above copyright 9*b2bdc62aSAdrian Chadd * notice, this list of conditions and the following disclaimer. 10*b2bdc62aSAdrian Chadd * 2. Redistributions in binary form must reproduce the above copyright 11*b2bdc62aSAdrian Chadd * notice, this list of conditions and the following disclaimer in the 12*b2bdc62aSAdrian Chadd * documentation and/or other materials provided with the distribution. 13*b2bdc62aSAdrian Chadd * 14*b2bdc62aSAdrian Chadd * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15*b2bdc62aSAdrian Chadd * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16*b2bdc62aSAdrian Chadd * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17*b2bdc62aSAdrian Chadd * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18*b2bdc62aSAdrian Chadd * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19*b2bdc62aSAdrian Chadd * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20*b2bdc62aSAdrian Chadd * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21*b2bdc62aSAdrian Chadd * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22*b2bdc62aSAdrian Chadd * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23*b2bdc62aSAdrian Chadd * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24*b2bdc62aSAdrian Chadd * SUCH DAMAGE. 25*b2bdc62aSAdrian Chadd */ 26*b2bdc62aSAdrian Chadd 27*b2bdc62aSAdrian Chadd #include <sys/cdefs.h> 28*b2bdc62aSAdrian Chadd __FBSDID("$FreeBSD$"); 29*b2bdc62aSAdrian Chadd 30*b2bdc62aSAdrian Chadd #include <sys/types.h> 31*b2bdc62aSAdrian Chadd 32*b2bdc62aSAdrian Chadd #include <net/rss_config.h> 33*b2bdc62aSAdrian Chadd #include <net/toeplitz.h> 34*b2bdc62aSAdrian Chadd 35*b2bdc62aSAdrian Chadd #include <sys/systm.h> 36*b2bdc62aSAdrian Chadd 37*b2bdc62aSAdrian Chadd uint32_t 38*b2bdc62aSAdrian Chadd toeplitz_hash(u_int keylen, const uint8_t *key, u_int datalen, 39*b2bdc62aSAdrian Chadd const uint8_t *data) 40*b2bdc62aSAdrian Chadd { 41*b2bdc62aSAdrian Chadd uint32_t hash = 0, v; 42*b2bdc62aSAdrian Chadd u_int i, b; 43*b2bdc62aSAdrian Chadd 44*b2bdc62aSAdrian Chadd /* XXXRW: Perhaps an assertion about key length vs. data length? */ 45*b2bdc62aSAdrian Chadd 46*b2bdc62aSAdrian Chadd v = (key[0]<<24) + (key[1]<<16) + (key[2] <<8) + key[3]; 47*b2bdc62aSAdrian Chadd for (i = 0; i < datalen; i++) { 48*b2bdc62aSAdrian Chadd for (b = 0; b < 8; b++) { 49*b2bdc62aSAdrian Chadd if (data[i] & (1<<(7-b))) 50*b2bdc62aSAdrian Chadd hash ^= v; 51*b2bdc62aSAdrian Chadd v <<= 1; 52*b2bdc62aSAdrian Chadd if ((i + 4) < RSS_KEYSIZE && 53*b2bdc62aSAdrian Chadd (key[i+4] & (1<<(7-b)))) 54*b2bdc62aSAdrian Chadd v |= 1; 55*b2bdc62aSAdrian Chadd } 56*b2bdc62aSAdrian Chadd } 57*b2bdc62aSAdrian Chadd return (hash); 58*b2bdc62aSAdrian Chadd } 59