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author | hrs <hrs@FreeBSD.org> | 2009-06-07 23:00:40 +0000 |
---|---|---|
committer | hrs <hrs@FreeBSD.org> | 2009-06-07 23:00:40 +0000 |
commit | 9bf362d0cc3f533a0c7e793fd354bfabfce44de6 (patch) | |
tree | 9a067cbb66c280e9da4ac4cea8c84e204039d753 /sys/netinet6 | |
parent | 92f847edaf37d804dffd489728e6af48a60a4fbb (diff) | |
download | FreeBSD-src-9bf362d0cc3f533a0c7e793fd354bfabfce44de6.zip FreeBSD-src-9bf362d0cc3f533a0c7e793fd354bfabfce44de6.tar.gz |
Fix and add a workaround on an issue of EtherIP packet with reversed
version field sent via gif(4)+if_bridge(4). The EtherIP
implementation found on FreeBSD 6.1, 6.2, 6.3, 7.0, 7.1, and 7.2 had
an interoperability issue because it sent the incorrect EtherIP
packets and discarded the correct ones.
This change introduces the following two flags to gif(4):
accept_rev_ethip_ver: accepts both correct EtherIP packets and ones
with reversed version field, if enabled. If disabled, the gif
accepts the correct packets only. This flag is enabled by
default.
send_rev_ethip_ver: sends EtherIP packets with reversed version field
intentionally, if enabled. If disabled, the gif sends the correct
packets only. This flag is disabled by default.
These flags are stored in struct gif_softc and can be set by
ifconfig(8) on per-interface basis.
Note that this is an incompatible change of EtherIP with the older
FreeBSD releases. If you need to interoperate older FreeBSD boxes and
new versions after this commit, setting "send_rev_ethip_ver" is
needed.
Reviewed by: thompsa and rwatson
Spotted by: Shunsuke SHINOMIYA
PR: kern/125003
MFC after: 2 weeks
Diffstat (limited to 'sys/netinet6')
-rw-r--r-- | sys/netinet6/in6_gif.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/sys/netinet6/in6_gif.c b/sys/netinet6/in6_gif.c index 7041841..68ebc9c 100644 --- a/sys/netinet6/in6_gif.c +++ b/sys/netinet6/in6_gif.c @@ -144,8 +144,22 @@ in6_gif_output(struct ifnet *ifp, #endif case AF_LINK: proto = IPPROTO_ETHERIP; - eiphdr.eip_ver = ETHERIP_VERSION & ETHERIP_VER_VERS_MASK; - eiphdr.eip_pad = 0; + + /* + * GIF_SEND_REVETHIP (disabled by default) intentionally + * sends an EtherIP packet with revered version field in + * the header. This is a knob for backward compatibility + * with FreeBSD 7.2R or prior. + */ + if ((sc->gif_options & GIF_SEND_REVETHIP)) { + eiphdr.eip_ver = 0; + eiphdr.eip_resvl = ETHERIP_VERSION; + eiphdr.eip_resvh = 0; + } else { + eiphdr.eip_ver = ETHERIP_VERSION; + eiphdr.eip_resvl = 0; + eiphdr.eip_resvh = 0; + } /* prepend Ethernet-in-IP header */ M_PREPEND(m, sizeof(struct etherip_header), M_DONTWAIT); if (m && m->m_len < sizeof(struct etherip_header)) |