T/TCP useless on FreeBSD 4.7?

Bruce M Simpson bms at spc.org
Fri Aug 1 08:26:40 PDT 2003


On Fri, Aug 01, 2003 at 11:14:12AM -0400, michael rabinovich wrote:
> Does anyone know the status of T/TCP support on FreeBSD 4.7?
...
> Am I missing something (after all, FreeBSD is supposed to be a ref 
> implementation of T/TCP!) and if not is there is a simple way around 
> this problem, short of going back to earlier FreeBSD releases?

I don't use T/TCP on my production 4.8-RELEASE system, and the following
sysctl values look fairly default:-

net.inet.tcp.rfc1644: 0
net.inet.tcp.syncookies: 1
net.inet.tcp.drop_synfin: 0

SYN cookies and T/TCP can't co-exist. Please do check the above sysctl
values; I know RFC 1644 has to be enabled, and syncookies have to be disabled,
as well as drop_synfin.

HTH,
BMS


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