Re: [squid-users] TProxy not faking source address.

rihad wrote:
> Looks like I'm the only one trying to use TProxy? Somebody else, please?
> To summarize: Squid does NOT spoof client's IP address when initiating
> connections on its own. Just as if there weren't a thing named "TProxy".

We have had a fair few trying it with complete success when its the only
thing used. This kind of thing seems to crop up with WCCP, for you and
one other.

I'm not sure yet what the problem seems to be. Can you check your
cache.log for messages about "Stopping full transparency", the rest of
the message says why. I've updated the wiki troubleshooting section to
list the messages that appear when tproxy is turned off automatically
and what needs to be done to fix it.

If you can't see any of those please can you set:
   debug_options ALL,1 89,6

to see whats going on?

I know the squid->client link should be 100% spoofed. I'm not fully
certain the quid->server link is actually spoofed in all cases. Though
one report indicates it may be, I have not been able to test it locally yet.

Amos

>
> Original message follows (not to be confused with top-posting):
>
>> Hello, I'm trying to get TProxy 4.1 to work as outlined here:
>> http://wiki.squid-cache.org/Features/Tproxy4
>> namely under Ubuntu 9.04 stable/testing mix with the following:
>> linux-image-2.6.28-11-server 2.6.28-11.42
>> iptables 1.4.3.2-2ubuntu1
>> squid-3.1.0.7.tar.bz2 from original sources
>>
>> Squid has been built this way:
>> $ /usr/local/squid/sbin/squid -v
>> Squid Cache: Version 3.1.0.7
>> configure options: '--enable-linux-netfilter'
>> --with-squid=/home/guessed/squid-3.1.0.7 --enable-ltdl-convenience
>> (myself I only gave it --enable-linux-netfilter)
>>
>> squid.conf is pretty much whatever 'make install' created, with my
>> changes given at the end, after the blank line:
>>
>> acl manager proto cache_object
>> acl localhost src 127.0.0.1/32
>> acl to_localhost dst 127.0.0.0/8
>> acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
>> acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
>> acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
>> acl SSL_ports port 443
>> acl Safe_ports port 80 # http
>> acl Safe_ports port 21 # ftp
>> acl Safe_ports port 443 # https
>> acl Safe_ports port 70 # gopher
>> acl Safe_ports port 210 # wais
>> acl Safe_ports port 1025-65535 # unregistered ports
>> acl Safe_ports port 280 # http-mgmt
>> acl Safe_ports port 488 # gss-http
>> acl Safe_ports port 591 # filemaker
>> acl Safe_ports port 777 # multiling http
>> acl CONNECT method CONNECT
>> http_access allow manager localhost
>> http_access deny manager
>> http_access deny !Safe_ports
>> http_access deny CONNECT !SSL_ports
>> http_access allow localnet
>> http_access deny all
>> http_port 3128
>> hierarchy_stoplist cgi-bin ?
>> refresh_pattern ^ftp: 1440 20% 10080
>> refresh_pattern ^gopher: 1440 0% 1440
>> refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
>> refresh_pattern . 0 20% 4320
>> coredump_dir /usr/local/squid/var/cache
>>
>> cache_dir ufs /usr/local/squid/var/cache 100 16 256
>> cache_mem 16 MB
>> http_port 3129 tproxy
>> visible_hostname tproxy
>>
>> Then I did:
>> iptables -t mangle -N DIVERT
>> iptables -t mangle -A DIVERT -j MARK --set-mark 1
>> iptables -t mangle -A DIVERT -j ACCEPT
>>
>> #Use DIVERT to prevent existing connections going through TPROXY twice:
>>
>> iptables -t mangle -A PREROUTING -p tcp -m socket -j DIVERT
>>
>> #Mark all other (new) packets and use TPROXY to pass into Squid:
>>
>> iptables -t mangle -A PREROUTING -p tcp --dport 80 -j TPROXY
>> --tproxy-mark 0x1/0x1 --on-port 3129
>>
>>
>> ip rule add fwmark 1 lookup 100
>> ip route add local 0.0.0.0/0 dev lo table 100
>>
>> #On each boot startup set:
>>
>> echo 1 > /proc/sys/net/ipv4/ip_forward
>>
>> ran squid -z and launched squid.
>>
>> My topology:
>> desktop where I sit: one link has address 192.168.0.1/24, the other to
>> the Internet
>> Squid box: one link: 192.168.0.184/24 (bridged VMware interface on the
>> same box as desktop), the other link is custom VMware interface
>> 192.168.1.1/24
>> The "client" box: single interface 192.168.1.2/24
>>
>> So, the squid box is directly connected to the outside on the one side,
>> and to the client on the other. My desktop's routing knows to reach the
>> client through the Squid box, and vice versa, so the port 80 traffic
>> under consideration flows through the Squid box in both ways.
>>
>> Now, after I do this on the "client":
>> $ telnet 192.168.0.1 80
>> GET / HTTP/1.0
>>
>> (correct webpage output)
>> Connection closed by foreign host.
>>
>> Nevertheless, in 192.168.0.1's webserver's logs I can see 192.168.0.184
>> connecting, not the TProxied 192.168.1.2, as if working under the plain
>> ole interception proxying I've been trying to get rid of!
>>
>> Why?! Counters on the Squid box do get bumped:
>>
>> $ sudo iptables -t mangle -L -v -n
>> Chain PREROUTING (policy ACCEPT 163 packets, 21851 bytes)
>> pkts bytes target prot opt in out source
>> destination
>> 2274 214K DIVERT tcp -- * * 0.0.0.0/0
>> 0.0.0.0/0 socket
>> 16 920 TPROXY tcp -- * * 0.0.0.0/0
>> 0.0.0.0/0 tcp dpt:80 TPROXY redirect 0.0.0.0:3129 mark 0x1/0x1
>>
>> ...
>>
>> Chain DIVERT (1 references)
>> pkts bytes target prot opt in out source
>> destination
>> 2274 214K MARK all -- * * 0.0.0.0/0
>> 0.0.0.0/0 MARK xset 0x1/0xffffffff
>> 2274 214K ACCEPT all -- * * 0.0.0.0/0
>> 0.0.0.0/0
>>
>>
>> Thanks for any tips.
>>
>>
>>
>>
>

-- 
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