From 0ec2d7d37af1a051b6b986ac285e0e47d4044d62 Mon Sep 17 00:00:00 2001 From: Ruslan Ermilov Date: Mon, 30 Oct 2000 09:44:20 +0000 Subject: [PATCH] IPFW does not discard *any* IP fragments with OFF=1, only TCP ones. --- sbin/ipfw/ipfw.8 | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/sbin/ipfw/ipfw.8 b/sbin/ipfw/ipfw.8 index 3e500432e036..3f7ef315a0c4 100644 --- a/sbin/ipfw/ipfw.8 +++ b/sbin/ipfw/ipfw.8 @@ -1052,12 +1052,14 @@ It is a good idea to be near the console when doing this. Don't forget the loopback interface. .El .Sh FINE POINTS +.Bl -bullet +.It There is one kind of packet that the firewall will always -discard, that is an IP fragment with a fragment offset of +discard, that is a TCP packet's fragment with a fragment offset of one. This is a valid packet, but it only has one use, to try to circumvent firewalls. -.Pp +.It If you are logged in over a network, loading the .Xr kld 4 version of @@ -1075,7 +1077,7 @@ ipfw flush .Ed .Pp in similar surroundings is also a bad idea. -.Pp +.It The .Nm filter list may not be modified if the system security level @@ -1085,6 +1087,7 @@ see .Xr init 8 for information on system security levels .Pc . +.El .Sh PACKET DIVERSION A .Xr divert 4