NetBSD/sys/net/agr/if_agrether_hash.c

149 lines
4.2 KiB
C

/* $NetBSD: if_agrether_hash.c,v 1.3 2007/05/05 18:23:23 yamt Exp $ */
/*-
* Copyright (c)2005 YAMAMOTO Takashi,
* 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_agrether_hash.c,v 1.3 2007/05/05 18:23:23 yamt Exp $");
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/hash.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_ether.h>
#include <net/if_vlanvar.h>
#include <net/agr/if_agrethervar.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#define HASH(p, l, h) hash32_buf((p), (l), (h))
static const void *agr_m_extract(struct mbuf *, int, int, void *);
static const void *
agr_m_extract(struct mbuf *m, int off, int len, void *buf)
{
const void *result;
KASSERT((m->m_flags & M_PKTHDR) != 0);
if (m->m_pkthdr.len < off + len) {
result = NULL;
} else if (m->m_len >= off + len) {
result = mtod(m, char *) + off;
} else {
m_copydata(m, off, len, buf);
result = buf;
}
return result;
}
uint32_t
agrether_hashmbuf(struct agr_softc *sc, struct mbuf *m)
{
struct ether_header eh_store;
const struct ether_header *eh;
uint32_t hash = HASH32_BUF_INIT;
int off = 0;
uint16_t tci;
uint16_t etype;
struct m_tag *mtag;
eh = agr_m_extract(m, off, sizeof(*eh), &eh_store);
if (eh == NULL) {
return hash;
}
hash = HASH(&eh->ether_dhost, sizeof(eh->ether_dhost), hash);
hash = HASH(&eh->ether_shost, sizeof(eh->ether_shost), hash);
etype = eh->ether_type;
if (etype == htobe16(ETHERTYPE_VLAN)) {
struct ether_vlan_header vlanhdr_store;
const struct ether_vlan_header *vlanhdr;
vlanhdr = agr_m_extract(m, off, sizeof(*vlanhdr),
&vlanhdr_store);
if (vlanhdr == NULL) {
return hash;
}
tci = vlanhdr->evl_tag;
etype = vlanhdr->evl_proto;
off += sizeof(*vlanhdr) - sizeof(*eh);
} else if ((mtag = m_tag_find(m, PACKET_TAG_VLAN, NULL)) != NULL) {
tci = htole16((*(u_int *)(mtag + 1)) & 0xffff);
} else {
tci = 0;
}
hash = HASH(&tci, sizeof(tci), hash);
off += sizeof(*eh);
if (etype == htobe16(ETHERTYPE_IP)) {
struct ip ip_store;
const struct ip *ip;
ip = agr_m_extract(m, off, sizeof(*ip), &ip_store);
if (ip == NULL) {
return hash;
}
hash = HASH(&ip->ip_src, sizeof(ip->ip_src), hash);
hash = HASH(&ip->ip_dst, sizeof(ip->ip_dst), hash);
hash = HASH(&ip->ip_p, sizeof(ip->ip_p), hash);
/* use port numbers for tcp and udp? */
} else if (etype == htobe16(ETHERTYPE_IPV6)) {
struct ip6_hdr ip6_store;
const struct ip6_hdr *ip6;
uint32_t flowlabel;
ip6 = agr_m_extract(m, off, sizeof(*ip6), &ip6_store);
if (ip6 == NULL) {
return hash;
}
hash = HASH(&ip6->ip6_src, sizeof(ip6->ip6_src), hash);
hash = HASH(&ip6->ip6_dst, sizeof(ip6->ip6_dst), hash);
/* hash = HASH(&ip6->ip6_nxt, sizeof(ip6->ip6_nxt), hash); */
flowlabel = ip6->ip6_flow & IPV6_FLOWLABEL_MASK;
hash = HASH(&flowlabel, sizeof(flowlabel), hash);
/* use port numbers for tcp and udp? */
}
return hash;
}