// // Copyright (c) 2017 Michael Tuexen // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions // are met: // 1. Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // 2. Redistributions in binary form must reproduce the above copyright // notice, this list of conditions and the following disclaimer in the // documentation and/or other materials provided with the distribution. // // THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE // ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS // OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) // HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT // LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY // OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF // SUCH DAMAGE. // --ip_version=ipv4 // Ensure that all relevant sysctl variables have their default values. 0.00 `sysctl -w net.inet.tcp.hostcache.purgenow=1` +0.00 `sysctl -w net.inet.tcp.syncookies_only=0` +0.00 `sysctl -w net.inet.tcp.syncookies=1` +0.00 `sysctl -w net.inet.tcp.rfc1323=1` +0.00 `sysctl -w net.inet.tcp.sack.enable=1` +0.00 `sysctl -w net.inet.tcp.ecn.enable=2` // First setup a TCP connection to get a TFO cookie +0.00 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0.00 sendto(3, ..., 100, 0, ..., ...) = 100 +0.00 > S 0:100(100) win 65535 +0.05 < S. 0:0(0) ack 101 win 32767 +0.00 > . 101:101(0) ack 1 win 65535 // Tear it down. Let the peer initiate the teardown to avoid the SUT // moving into TIMEWAIT state. +0.00 < F. 1:1(0) ack 101 win 65535 +0.00 > . 101:101(0) ack 2 win 65535 +0.00 close(3) = 0 +0.00 > F. 101:101(0) ack 2 win 65535 +0.05 < . 2:2(0) ack 102 win 65534