diff options
Diffstat (limited to 'sys/net/toeplitz.c')
| -rw-r--r-- | sys/net/toeplitz.c | 55 |
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); +} |
