Module Name: src
Committed By: yamaguchi
Date: Fri Oct 22 06:20:47 UTC 2021
Modified Files:
src/sys/net/lagg: if_lagg.c
Log Message:
lagg: change hash logic to generate the same value
when pairs of source and destination are the same
To generate a diff of this commit:
cvs rdiff -u -r1.16 -r1.17 src/sys/net/lagg/if_lagg.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/net/lagg/if_lagg.c
diff -u src/sys/net/lagg/if_lagg.c:1.16 src/sys/net/lagg/if_lagg.c:1.17
--- src/sys/net/lagg/if_lagg.c:1.16 Tue Oct 19 08:02:42 2021
+++ src/sys/net/lagg/if_lagg.c Fri Oct 22 06:20:47 2021
@@ -1,4 +1,4 @@
-/* $NetBSD: if_lagg.c,v 1.16 2021/10/19 08:02:42 yamaguchi Exp $ */
+/* $NetBSD: if_lagg.c,v 1.17 2021/10/22 06:20:47 yamaguchi Exp $ */
/*
* Copyright (c) 2005, 2006 Reyk Floeter <r...@openbsd.org>
@@ -20,7 +20,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_lagg.c,v 1.16 2021/10/19 08:02:42 yamaguchi Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_lagg.c,v 1.17 2021/10/22 06:20:47 yamaguchi Exp $");
#ifdef _KERNEL_OPT
#include "opt_inet.h"
@@ -876,7 +876,7 @@ lagg_hashmbuf(struct lagg_softc *sc, str
const struct ip6_hdr *ip6;
const struct tcphdr *th;
const struct udphdr *uh;
- uint32_t hash = HASH32_BUF_INIT;
+ uint32_t hash, hash_src, hash_dst;
uint32_t flowlabel;
uint16_t etype, vlantag;
uint8_t proto;
@@ -884,9 +884,17 @@ lagg_hashmbuf(struct lagg_softc *sc, str
KASSERT(ISSET(m->m_flags, M_PKTHDR));
+ hash = HASH32_BUF_INIT;
+ hash_src = HASH32_BUF_INIT;
+ hash_dst = HASH32_BUF_INIT;
+
+#define LAGG_HASH_ADD(hp, v) do { \
+ *(hp) = hash32_buf(&(v), sizeof(v), *(hp)); \
+} while(0)
+
eh = lagg_m_extract(m, 0, sizeof(*eh), &buf);
if (eh == NULL) {
- return hash;
+ goto out;
}
off = ETHER_HDR_LEN;
etype = ntohs(eh->ether_type);
@@ -894,7 +902,7 @@ lagg_hashmbuf(struct lagg_softc *sc, str
if (etype == ETHERTYPE_VLAN) {
evl = lagg_m_extract(m, 0, sizeof(*evl), &buf);
if (evl == NULL) {
- return hash;
+ goto out;
}
vlantag = ntohs(evl->evl_tag);
@@ -907,26 +915,22 @@ lagg_hashmbuf(struct lagg_softc *sc, str
}
if (sc->sc_hash_mac) {
- hash = hash32_buf(&eh->ether_dhost,
- sizeof(eh->ether_dhost), hash);
- hash = hash32_buf(&eh->ether_shost,
- sizeof(eh->ether_shost), hash);
- hash = hash32_buf(&vlantag, sizeof(vlantag), hash);
+ LAGG_HASH_ADD(&hash_dst, eh->ether_dhost);
+ LAGG_HASH_ADD(&hash_src, eh->ether_shost);
+ LAGG_HASH_ADD(&hash, vlantag);
}
switch (etype) {
case ETHERTYPE_IP:
ip = lagg_m_extract(m, off, sizeof(*ip), &buf);
if (ip == NULL) {
- return hash;
+ goto out;
}
if (sc->sc_hash_ipaddr) {
- hash = hash32_buf(&ip->ip_src,
- sizeof(ip->ip_src), hash);
- hash = hash32_buf(&ip->ip_dst,
- sizeof(ip->ip_dst), hash);
- hash = hash32_buf(&ip->ip_p, sizeof(ip->ip_p), hash);
+ LAGG_HASH_ADD(&hash_src, ip->ip_src);
+ LAGG_HASH_ADD(&hash_dst, ip->ip_dst);
+ LAGG_HASH_ADD(&hash, ip->ip_p);
}
off += ip->ip_hl << 2;
proto = ip->ip_p;
@@ -934,22 +938,19 @@ lagg_hashmbuf(struct lagg_softc *sc, str
case ETHERTYPE_IPV6:
ip6 = lagg_m_extract(m, off, sizeof(*ip6), &buf);
if (ip6 == NULL) {
- return hash;
+ goto out;
}
if (sc->sc_hash_ip6addr) {
- hash = hash32_buf(&ip6->ip6_src,
- sizeof(ip6->ip6_src), hash);
- hash = hash32_buf(&ip6->ip6_dst,
- sizeof(ip6->ip6_dst), hash);
+ LAGG_HASH_ADD(&hash_src, ip6->ip6_src);
+ LAGG_HASH_ADD(&hash_dst, ip6->ip6_dst);
flowlabel = ip6->ip6_flow & IPV6_FLOWLABEL_MASK;
- hash = hash32_buf(&flowlabel, sizeof(flowlabel), hash);
+ LAGG_HASH_ADD(&hash, flowlabel);
}
proto = ip6->ip6_nxt;
off += sizeof(*ip6);
+ break;
- /* L4 header is not supported */
- return hash;
default:
return hash;
}
@@ -958,31 +959,32 @@ lagg_hashmbuf(struct lagg_softc *sc, str
case IPPROTO_TCP:
th = lagg_m_extract(m, off, sizeof(*th), &buf);
if (th == NULL) {
- return hash;
+ goto out;
}
if (sc->sc_hash_tcp) {
- hash = hash32_buf(&th->th_sport,
- sizeof(th->th_sport), hash);
- hash = hash32_buf(&th->th_dport,
- sizeof(th->th_dport), hash);
+ LAGG_HASH_ADD(&hash_src, th->th_sport);
+ LAGG_HASH_ADD(&hash_dst, th->th_dport);
}
break;
case IPPROTO_UDP:
uh = lagg_m_extract(m, off, sizeof(*uh), &buf);
if (uh == NULL) {
- return hash;
+ goto out;
}
if (sc->sc_hash_udp) {
- hash = hash32_buf(&uh->uh_sport,
- sizeof(uh->uh_sport), hash);
- hash = hash32_buf(&uh->uh_dport,
- sizeof(uh->uh_dport), hash);
+ LAGG_HASH_ADD(&hash_src, uh->uh_sport);
+ LAGG_HASH_ADD(&hash_dst, uh->uh_dport);
}
break;
}
+out:
+ hash_src ^= hash_dst;
+ LAGG_HASH_ADD(&hash, hash_src);
+#undef LAGG_HASH_ADD
+
return hash;
}
