diff options
Diffstat (limited to 'share/man/man4/inet.4')
-rw-r--r-- | share/man/man4/inet.4 | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/share/man/man4/inet.4 b/share/man/man4/inet.4 index b0b5a9e..3a2bf8a 100644 --- a/share/man/man4/inet.4 +++ b/share/man/man4/inet.4 @@ -28,7 +28,7 @@ .\" From: @(#)inet.4 8.1 (Berkeley) 6/5/93 .\" $FreeBSD$ .\" -.Dd January 26, 2012 +.Dd April 2, 2015 .Dt INET 4 .Os .Sh NAME @@ -226,12 +226,24 @@ This .Xr sysctl 8 variable affects packets destined for a local host as well as packets forwarded to some other host. +.It Va ip.rfc6864 +Boolean: control IP IDs generation behaviour. +True value enables RFC6864 support, which specifies that IP ID field of +.Em atomic +datagrams can be set to any value. +The +.Fx implementation sets it to zero. +Enabled by default. .It Va ip.random_id Boolean: control IP IDs generation behaviour. Setting this .Xr sysctl 8 -to non-zero causes the ID field in IP packets to be randomized instead of -incremented by 1 with each packet generated. +to 1 causes the ID field in +.Em non-atomic +IP datagrams (or all IP datagrams, if +.Va ip.rfc6864 +is disabled) to be randomized instead of incremented by 1 with each packet +generated. This closes a minor information leak which allows remote observers to determine the rate of packet generation on the machine by watching the counter. |