Re: [squid-users] Squid - WCCP and ASA

Amos,

Is there any compilation option that I am missing to make squid
transparent??? maybe that's what's missing?. This is the 3.0 release.

-Parvinder Bhasin

On Jun 17, 2009, at 8:16 AM, Amos Jeffries wrote:

> Parvinder Bhasin wrote:
>> Amos,
>> The tunnel is actually between the ASA and WCCP enabled squid.
>
> No tunnel is between ASA and the squid box Operating System.
>
> Squid itself has nothing to do with the tunnel. Squids only concern
> is that the packets are arriving via some interception method. Thus
> the src/dst IPs are a bit strange and it needs "transparent" or
> "intercept" http_port option to handle.
>
>
>> All the examples on squid-cache site as well as googling this issue
>> points to creating a tunnel like this. Are you saying I don't need
>> tunnel??? external ip???
>
> No you still need the tunnel. But I think assigning localhost-only
> address to it may be a bad thing.
>
> The other tunnels I know about all need an IP the firewall device
> can send to. Try without it to see if our packets start appearing.
>
>
>> the squid box has an internal interface and is not connected to the
>> internet directly.
>
> There are three categories of traffic interface:
> WAN - Internet facing
> LAN - local network facing
> localhost - not even getting past the NIC onto the wire.
>
>> The squid box itself goes out the ASA and fetches the pages.
>> Basically its NATed.
>
> Can you trace the packets as far as reaching Squid and starting
> their way out again though?
> If so the tunnels etc are fine. But the routing exemption to allow
> for Squid box connections out through the router may be whacked.
>
> Amos
>
>> -Parvinder Bhasin
>> On Jun 16, 2009, at 5:51 PM, Amos Jeffries wrote:
>>> On Tue, 16 Jun 2009 16:49:56 -0700, Parvinder Bhasin
>>> <parvinder.bhasin_at_gmail.com> wrote:
>>>> I have setup of squid ..which was compiled with --enable-delay-
>>>> pools
>>>> option. Works really well but without WCCP.
>>>> I enabled WCCP support in the squid config and also enabled wccp
>>>> support on my ASA. Setup GRE tunnel etc.
>>>> For my testing purpose I am only having ONE client IP go through
>>>> WCCP. The problem is I am able to see that client on the GRE1
>>>> interface (the requests) of the proxy server but that client is not
>>>> getting anything back reply back. Do I need anything in iptables
>>>> to
>>>> allow etc??? do I need to compile with some transparent
>>>> support?? if
>>>> so which one would I use for ASA?
>>>>
>>>> Any help is highly appreciated.
>>>>
>>>>
>>>> Here is part of my config:
>>>>
>>>> http_port 3128 transparent
>>>>
>>>> wccp2_router 192.168.100.250
>>>> wccp_version 4
>>>> wccp2_forwarding_method 1
>>>> wccp2_return_method 1
>>>> wccp2_service standard 0
>>>>
>>>> Additionally here is what I did to setup tunnel:
>>>>
>>>> modprobe ip_gre
>>>> iptunnel add gre1 mode gre remote $ASA_IP local $LOCAL_IP dev eth0
>>>> ifconfig gre1 inet 127.0.0.2 netmask 255.255.255.0 up
>>>>
>>>
>>> IIRC localhost IDs 127.0.0.0/8 are hardware-limited to only be
>>> usable for
>>> traffic internal to the box.
>>> If WCCP is going on a tunnel it will likely need an externally
>>> visible IP
>>> for the router to send to.
>>>
>>>> echo 1 > /proc/sys/net/ipv4/ip_forward
>>>> echo 0 > /proc/sys/net/ipv4/tcp_window_scaling
>>>> echo 0 > /proc/sys/net/ipv4/conf/default/rp_filter
>>>> echo 0 > /proc/sys/net/ipv4/conf/all/rp_filter
>>>> echo 0 > /proc/sys/net/ipv4/conf/eth0/rp_filter
>>>> echo 0 > /proc/sys/net/ipv4/conf/lo/rp_filter
>>>> echo 0 > /proc/sys/net/ipv4/conf/gre1/rp_filter
>>>>
>>>> iptables -t nat -A PREROUTING -i gre1 -p tcp -m tcp --dport 80 -j
>>>> REDIRECT --to-port
>>>> 3128
>>>>
>>>> I do see the RX counter going up but not the TX on gre1:
>>>>
>>>> gre1 Link encap:UNSPEC HWaddr C0-A8-64-CF-B7-BF-C8-
>>>> C2-00-00-00-00-00-00-00-00
>>>> inet addr:127.0.0.2 P-t-P:127.0.0.2 Mask:255.255.255.0
>>>> UP POINTOPOINT RUNNING NOARP MTU:1476 Metric:1
>>>> RX packets:1559 errors:0 dropped:0 overruns:0 frame:0
>>>> TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
>>>> collisions:0 txqueuelen:0
>>>> RX bytes:83432 (81.4 KiB) TX bytes:0 (0.0 b)
>>>>
>>>> Here is tcpdump output:
>>>>
>>>> [root_at_squidnclamav etc]# tcpdump -i gre1 host 192.168.100.175 and
>>>> port
>>>> not ssh
>>>> tcpdump: WARNING: arptype 778 not supported by libpcap - falling
>>>> back
>>>> to cooked socket
>>>> tcpdump: verbose output suppressed, use -v or -vv for full protocol
>>>> decode
>>>> listening on gre1, link-type LINUX_SLL (Linux cooked), capture
>>>> size 96
>>>> bytes
>>>> 14:13:37.615862 IP 192.168.100.175.52257 > cf-in-
>>>> f99.google.com.http:
>>>> S 3689381709:3689381709(0) win 65535 <mss 1460,sackOK,eol>
>>>> 14:13:45.524999 IP 192.168.100.175.52256 >
>>>> bs2.ads.vip.sp1.yahoo.com.http: S 2516726129:2516726129(0) win
>>>> 65535
>>>> <mss 1460,sackOK,eol>
>>>> 14:13:45.525001 IP 192.168.100.175.52255 >
>>>> bs2.ads.vip.sp1.yahoo.com.http: S 878462413:878462413(0) win 65535
>>>> <mss 1460,sackOK,eol>
>>>> 14:13:45.525002 IP 192.168.100.175.52254 >
>>>> bs2.ads.vip.sp1.yahoo.com.http: S 1528706489:1528706489(0) win
>>>> 65535
>>>> <mss 1460,sackOK,eol>
>>>> 14:13:45.525003 IP 192.168.100.175.52253 >
>>>> bs2.ads.vip.sp1.yahoo.com.http: S 1578413587:1578413587(0) win
>>>> 65535
>>>> <mss 1460,sackOK,eol>
>>>> 14:13:47.427509 IP 192.168.100.175.52252 >
>>>> mc2b.mail.vip.re1.yahoo.com.http: S 3796070861:3796070861(0) win
>>>> 65535
>>>> <mss 1460,sackOK,eol>
>>>> 14:13:47.886251 IP 192.168.100.175.52259 >
>>>> f1.www.vip.sp1.yahoo.com.http: S 1111547104:1111547104(0) win 65535
>>>> <mss 1460,nop,wscale 3,nop,nop,timestamp 322113293 0,sackOK,eol>
>>>> 14:13:48.127001 IP 192.168.100.175.52260 > hp-core.ebay.com.http: S
>>>> 357937093:357937093(0) win 65535 <mss 1460,nop,wscale
>>>> 3,nop,nop,timestamp 322113295 0,sackOK,eol>
>>>> 14:13:48.829652 IP 192.168.100.175.52259 >
>>>> f1.www.vip.sp1.yahoo.com.http: S 1111547104:1111547104(0) win 65535
>>>> <mss 1460,nop,wscale 3,nop,nop,timestamp 322113302 0,sackOK,eol>
>>>> 14:13:49.029600 IP 192.168.100.175.52260 > hp-core.ebay.com.http: S
>>>> 357937093:357937093(0) win 65535 <mss 1460,nop,wscale
>>>> 3,nop,nop,timestamp 322113304 0,sackOK,eol>
>>>> 14:13:49.820922 IP 192.168.100.175.52259 >
>>>> f1.www.vip.sp1.yahoo.com.http: S 1111547104:1111547104(0) win 65535
>>>> <mss 1460,nop,wscale 3,nop,nop,timestamp 322113312 0,sackOK,eol>
>>>> 14:13:50.030914 IP 192.168.100.175.52260 > hp-core.ebay.com.http: S
>>>> 357937093:357937093(0) win 65535 <mss 1460,nop,wscale
>>>> 3,nop,nop,timestamp 322113314 0,sackOK,eol>
>
>
> --
> Please be using
> Current Stable Squid 2.7.STABLE6 or 3.0.STABLE16
> Current Beta Squid 3.1.0.8
Received on Thu Jun 18 2009 - 19:37:08 MDT