Greetings,We're working to attempt to get a completely transparent proxy up and running. By completely transparent I mean:
1) The web server should see the clients' actual IP (not the proxy)2) The client should see the response coming back from the IP of the web server.
We're trying to implement this with WCCPv2 Interception on a 7204vxr/NPE-G1 with IOS 12.3.15a.
The configuration guide has been explicitly followed at: http://wiki.squid-cache.org/Features/Tproxy4The machine is running CentOS 6. I've tried with the stock kernel, and with 3.6.5 installed from elrepo.org. selinux is disabled. Using the non-tproxy port in squid by explicitly configuring the proxy, successfully proxies & caches traffic (proxy server ip reported by web server).
Squid version is 3.1.10-9.el6_3 from CentOS6 repository. All commands successfully complete, but the proxy isn't working. I've observed that:1) The Cisco router sees the web cache as reported by "sh ip wccp" (see attached sh_ip_wccp.txt).
2) tcpdump -i tun0 reports packets arriving from the Cisco router.3) tcpdump -i eth2 reports packets leaving the cache server bound for the destination web server
4) The destination web server shows no hits in the access_log file5) tcpdump on the web server shows packets arriving from the client IP address on port 80.
6) tcpdump on the web server shows packets leaving bound for the client IP7) The client browser times out, receiving an HTML error from Squid reporting "Connection to <server ip> failed." 8) When the timeout occurs, the squid access log reports "TCP_MISS/504 4123 GET http://myip.valnet.net/ - DIRECT/64.254.32.23 text/html"
I've attached numerous files containing statuses of various things that need to be set, such as rp_filter sysctl values, output of "show ip wccp", the squid.conf file, the cisco configuration, and the contents of iptables.
Any advice appreciated. Thanks, -- ----------------------------------------------- - Nick Bright - - Vice President of Technology - - Valnet -=- We Connect You -=- - - Tel 888-332-1616 x 315 / Fax 620-331-0789 - - Web http://www.valnet.net/ - ----------------------------------------------- - Are your files safe? - - Valnet Vault - Secure Cloud Backup - - More information & 30 day free trial at - - http://www.valnet.net/services/valnet-vault - -----------------------------------------------
Using 1599 out of 522232 bytes ! version 12.3 service timestamps debug datetime msec service timestamps log datetime msec service password-encryption ! hostname test-router ! boot-start-marker boot-end-marker ! no aaa new-model ip subnet-zero ip wccp web-cache redirect-list 120 ! ip name-server 64.254.32.10 ! ip cef ! interface GigabitEthernet0/1 description Link to Internet ip address 64.254.32.5 255.255.255.0 duplex auto speed auto media-type rj45 negotiation auto ! interface GigabitEthernet0/2 description LAN to provide Caching for ip address 64.254.49.1 255.255.255.192 ip wccp 80 redirect in ip wccp 90 redirect out duplex auto speed auto media-type rj45 negotiation auto ! interface GigabitEthernet0/3 description Dedicated port to Cache server ip address 64.254.33.1 255.255.255.252 ip wccp redirect exclude in duplex auto speed auto media-type rj45 negotiation auto ! ip classless ip route 0.0.0.0 0.0.0.0 64.254.32.1 no ip http server ! ! access-list 10 remark proxy server ip access-list 10 permit 64.254.33.2 access-list 120 remark ACL for WCCP proxy access access-list 120 remark Squid proxies bypass WCCP access-list 120 deny ip host 64.254.33.2 any access-list 120 remark LAN clients proxy port 80 only access-list 120 permit tcp 64.254.49.0 0.0.0.255 any eq www access-list 120 remark all others bypass WCCP access-list 120 deny ip any any ! ! gatekeeper shutdown ! ! line con 0 stopbits 1 line aux 0 line vty 0 4 ! end
[root@cache ~]# iptables -t mangle -L Chain PREROUTING (policy ACCEPT) target prot opt source destination DIVERT tcp -- anywhere anywhere socket TPROXY tcp -- anywhere anywhere tcp dpt:http TPROXY redirect 0.0.0.0:3128 mark 0x1/0x1 Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination Chain DIVERT (1 references) target prot opt source destination MARK all -- anywhere anywhere MARK set 0x1 ACCEPT all -- anywhere anywhere [root@cache ~]# iptables -t nat -L Chain PREROUTING (policy ACCEPT) target prot opt source destination Chain INPUT (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain POSTROUTING (policy ACCEPT) target prot opt source destination [root@cache ~]# iptables -L Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT all -- anywhere anywhere ACCEPT gre -- anywhere anywhere Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination
test-router>sh ip wccp
Global WCCP information:
Router information:
Router Identifier: 64.254.49.1
Protocol Version: 2.0
Service Identifier: web-cache
Number of Cache Engines: 0
Number of routers: 0
Total Packets Redirected: 0
Redirect access-list: 120
Total Packets Denied Redirect: 0
Total Packets Unassigned: 0
Group access-list: -none-
Total Messages Denied to Group: 0
Total Authentication failures: 0
Service Identifier: 80
Number of Cache Engines: 1
Number of routers: 1
Total Packets Redirected: 680
Redirect access-list: 120
Total Packets Denied Redirect: 0
Total Packets Unassigned: 4
Group access-list: -none-
Total Messages Denied to Group: 0
Total Authentication failures: 0
Service Identifier: 90
Number of Cache Engines: 1
Number of routers: 1
Total Packets Redirected: 0
Redirect access-list: 120
Total Packets Denied Redirect: 2619
Total Packets Unassigned: 4
Group access-list: -none-
Total Messages Denied to Group: 0
Total Authentication failures: 0acl manager proto cache_object acl localhost src 127.0.0.1/32 ::1 acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1 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 localnet src fc00::/7 # RFC 4193 local private network range acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines 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 allow CONNECT !SSL_ports acl publicnet src 64.254.49.0/26 # Testing Subnet http_access allow localnet http_access allow localhost http_access allow publicnet http_access deny all http_port 3127 http_port 3128 tproxy hierarchy_stoplist cgi-bin ? cache_dir ufs /var/cache/squid 150000 16 256 coredump_dir /var/spool/squid 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 visible_hostname cache.valnet.net store_avg_object_size 10 MB wccp2_router 64.254.33.1 wccp2_forwarding_method gre wccp2_return_method gre wccp2_service dynamic 80 wccp2_service_info 80 protocol=tcp flags=src_ip_hash priority=240 ports=80 wccp2_service dynamic 90 wccp2_service_info 90 protocol=tcp flags=dst_ip_hash,ports_source priority=240 ports=80
[root@cache ~]# cat /proc/sys/net/ipv4/conf/tun0/rp_filter 0 [root@cache ~]# cat /proc/sys/net/ipv4/conf/eth2/rp_filter 0 [root@cache ~]# cat /proc/sys/net/ipv4/ip_forward 1
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