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Diffstat (limited to 'net/netfilter/Kconfig')
| -rw-r--r-- | net/netfilter/Kconfig | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig index 614c92c17835..748f7f00909a 100644 --- a/net/netfilter/Kconfig +++ b/net/netfilter/Kconfig @@ -395,6 +395,32 @@ config NETFILTER_XT_TARGET_CONNSECMARK To compile it as a module, choose M here. If unsure, say N. +config NETFILTER_XT_TARGET_TCPMSS + tristate '"TCPMSS" target support' + depends on NETFILTER_XTABLES && (IPV6 || IPV6=n) + ---help--- + This option adds a `TCPMSS' target, which allows you to alter the + MSS value of TCP SYN packets, to control the maximum size for that + connection (usually limiting it to your outgoing interface's MTU + minus 40). + + This is used to overcome criminally braindead ISPs or servers which + block ICMP Fragmentation Needed packets. The symptoms of this + problem are that everything works fine from your Linux + firewall/router, but machines behind it can never exchange large + packets: + 1) Web browsers connect, then hang with no data received. + 2) Small mail works fine, but large emails hang. + 3) ssh works fine, but scp hangs after initial handshaking. + + Workaround: activate this option and add a rule to your firewall + configuration like: + + iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN \ + -j TCPMSS --clamp-mss-to-pmtu + + To compile it as a module, choose M here. If unsure, say N. + config NETFILTER_XT_MATCH_COMMENT tristate '"comment" match support' depends on NETFILTER_XTABLES |