[tor-bugs] #18819 [Tor]: ORPort listening on one IP, but listening on another

[Tor Bug Tracker & Wiki]

#18819: ORPort listening on one IP, but listening on another
------------------------+--------------------------
     Reporter:  reezer  |      Owner:
         Type:  defect  |     Status:  new
     Priority:  Medium  |  Milestone:
    Component:  Tor     |    Version:  Tor: 0.2.7.6
     Severity:  Normal  |   Keywords:
Actual Points:          |  Parent ID:
       Points:          |   Reviewer:
      Sponsor:          |
------------------------+--------------------------
 When I tell Tor to listen on one IP it (according to the log) still
 advertises itself on a different IP.

 I am running the following configuration. The only change are the x's on
 IPs. Nothing else was removed or changed. See how the IP ends with .81.

 {{{
 SocksPort 0
 ORPort x.x.x.81:33075
 BridgeRelay 1
 Exitpolicy reject *:*
 User _tor

 Nickname xxx
 ContactInfo xxx

 # Logging
 Log notice file /var/log/tor.log

 # Enable the Extended ORPort
 ExtORPort auto
 ServerTransportPlugin obfs3 exec xxx/bin/obfs4proxy
 ServerTransportPlugin obfs4 exec xxx/bin/obfs4proxy

 ServerTransportListenAddr obfs3 x.x.x.81:33074
 ServerTransportListenAddr obfs4 x.x.x.81:443
 }}}

 When starting Tor (nothing but status lines that have been replaced with
 ... removed) it correctly outputs the listening ip, but still advertises
 on another ip (.81 vs .172).

 {{{
 Apr 14 11:06:58.110 [notice] Tor v0.2.7.6 running on FreeBSD with Libevent
 2.0.22-stable, OpenSSL 1.0.2g and Zlib 1.2.8.
 ...
 Apr 14 11:06:58.135 [notice] Opening OR listener on x.x.x.81:33075
 Apr 14 11:06:58.135 [notice] Opening Extended OR listener on 127.0.0.1:0
 Apr 14 11:06:58.136 [notice] Extended OR listener listening on port 22692.
 ...
 Apr 14 11:06:59.000 [notice] Bootstrapped 0%: Starting
 Apr 14 11:07:00.000 [notice] Bootstrapped 5%: Connecting to directory
 server
 Apr 14 11:07:35.000 [notice] Bootstrapped 80%: Connecting to the Tor
 network
 Apr 14 11:07:35.000 [notice] Bootstrapped 85%: Finishing handshake with
 first hop
 Apr 14 11:07:36.000 [notice] Registered server transport 'obfs3' at
 'x.x.x.81:33074'
 Apr 14 11:07:36.000 [notice] Registered server transport 'obfs4' at
 'x.x.x.81:443'
 Apr 14 11:07:37.000 [notice] Bootstrapped 90%: Establishing a Tor circuit
 Apr 14 11:07:37.000 [notice] Tor has successfully opened a circuit. Looks
 like client functionality is working.
 Apr 14 11:07:37.000 [notice] Bootstrapped 100%: Done
 Apr 14 11:07:37.000 [notice] Now checking whether ORPort x.x.x.172:33075
 is reachable... (this may take up to 20 minutes -- look for log messages
 indicating success)
 }}}


 ifconfig output. See how the interface has two IP addresses. Tor appears
 to be looking at the first one for advertisement, despite ORPort being set
 to the second one.

 {{{
 em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
 options=4219b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM,TSO4,WOL_MAGIC,VLAN_HWTSO>
         ether xx:xx:xx:xx:xx:x
         inet x.x.x.172 netmask 0xffffff00 broadcast x.x.x.255
         inet x.x.x.81 netmask 0xffffff00 broadcast x.x.x.255
 }}}

 sockstat (similar to netstat) output:

 {{{
 USER     COMMAND    PID   FD PROTO  LOCAL ADDRESS         FOREIGN ADDRESS
 _tor     tor        12580 5  tcp4   x.x.x.81:33075   *:*
 }}}

 Command Line:
 {{{
 /usr/local/bin/tor -f /usr/local/etc/tor/torrc --PidFile
 /var/run/tor/tor.pid --RunAsDaemon 1 --DataDirectory /var/db/tor
 }}}

 Also Tor isn't running in a jail and there is nothing else I can think of
 affecting it.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/18819>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online