Random source ports in FreeBSD?

Dmitry Pryanishnikov dmitry at atlantis.dp.ua
Mon Sep 20 03:13:52 PDT 2004


Hello!

On Sat, 18 Sep 2004, Mike Silbersack wrote:
>> So, as far as I got to know, randomizing source ports in FreeBSD is
>> impossible now? (to be exact - is not implemented?)
>> 
>> It's very interesting to me - WHY is it so?
>> I mean - may be there are good reasons for not making all this?..
>
> Source port randomization was implemented before 4.10 was released.  See 
> in_pcb.c revisions 1.143 - 1.146, 1.59.2.27, or 1.59.2.27.2.1, depending on 
> the branch you're interested in:
>
> http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/netinet/in_pcb.c

  Yes, source port randomization works in 4.10-RELEASE, but port number 
sequence tends to give the same port number every 100-200 ports. Local
FTP install of 4.10-RELEASE always fail for me, as a workaround I'm forced
to issue sysctl net.inet.ip.portrange.randomized=0 before reselecting FTP
server in sysinstall. Are there plans to fix the quality of random port number 
generation under 4-STABLE?

Sincerely, Dmitry
-- 
Atlantis ISP, System Administrator
e-mail:  dmitry at atlantis.dp.ua
nic-hdl: LYNX-RIPE


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