netdev - TCP port randomization

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Date:	Wed, 17 Oct 2007 23:15:48 +0200 (CEST)
From:	Krzysztof Oledzki <olel@....pl>
To:	Stephen Hemminger <shemminger@...ux-foundation.org>
cc:	netdev@...r.kernel.org
Subject: TCP port randomization

Hello,

Is it normal that TCP port randomization (tested with 2.6.22) works only 
when explicitly binding to a IP address:


--- cut here ---
root@fw1:~# nc 192.168.129.28 11
(UNKNOWN) [192.168.129.28] 11 (systat) : Connection refused
root@fw1:~# nc 192.168.129.28 11
(UNKNOWN) [192.168.129.28] 11 (systat) : Connection refused
root@fw1:~# nc 192.168.129.28 11
(UNKNOWN) [192.168.129.28] 11 (systat) : Connection refused

23:11:11.896126 IP 192.168.129.2.37839 > 192.168.129.28.11: S
23:11:12.146573 IP 192.168.129.2.37840 > 192.168.129.28.11: S
23:11:12.396488 IP 192.168.129.2.37841 > 192.168.129.28.11: S
--- cut here ---


--- cut here ---
root@fw1:~# nc -s 192.168.129.2 192.168.129.28 11
(UNKNOWN) [192.168.129.28] 11 (systat) : Connection refused
root@fw1:~# nc -s 192.168.129.2 192.168.129.28 11
(UNKNOWN) [192.168.129.28] 11 (systat) : Connection refused
root@fw1:~# nc -s 192.168.129.2 192.168.129.28 11
(UNKNOWN) [192.168.129.28] 11 (systat) : Connection refused

23:11:31.704391 IP 192.168.129.2.57204 > 192.168.129.28.11: S
23:11:34.400048 IP 192.168.129.2.14512 > 192.168.129.28.11: S
23:11:34.606707 IP 192.168.129.2.20117 > 192.168.129.28.11: S
--- cut here ---

Best regards,

 				Krzysztof Olędzki