[squid-users] http_access deny for dstdomain acl not denying access to url.. what am I doing wrong?

Wed Oct 15 06:13:04 UTC 2014

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And the key difference in these configs is not the ACL contents, but
the ordering in which they are matched.

Mirzas' config starts by telling Squid everything on the LAN/localnet
is allowed. Ok, fine, Squid will do that.

Walters' config will tell Squid a limited set of things to allow, then
some things to deny, then implicitly allow everything else [1][2].
Whichever rule actually matches the FB requests will be applied by
Squid, with a limited set of initial allow/bypass the likelihood that
a deny following will match is higher.

[1] this is not a great situation, because any remote attack which can
figure out a way past your regex ACLs can use the proxy for whatever
they please[2].

[2] I hope you just omitted the localnet ACL checks which should
follow the ones you showed.

Amos

On 15/10/2014 6:56 p.m., Walter H. wrote:
> acl allow_urls url_regex -i "/etc/squid/allowurls-regex-acl.squid"
> (a) acl block_urls url_regex -i
> "/etc/squid/blockurls-regex-acl.squid" (b) acl allow_urlpaths
> urlpath_regex -i "/etc/squid/allowurlpaths-regex-acl.squid" (c) acl
> block_urlpaths urlpath_regex -i 
> "/etc/squid/blockurlpaths-regex-acl.squid" (d) acl
> allow_domains_list dstdomain 
> "/etc/squid/allowdomains-list-acl.squid" (e) acl block_domains_list
> dstdomain "/etc/squid/blockdomains-list-acl.squid" (f) acl
> block_domains_listex dstdomain 
> "/etc/squid/blockdomains-listex-acl.squid" (g) acl
> allow_domains_regex dstdom_regex -i 
> "/etc/squid/allowdomains-regex-acl.squid" (h) acl
> block_domains_regex dstdom_regex -i 
> "/etc/squid/blockdomains-regex-acl.squid" (i) acl block_hosts_list
> dst "/etc/squid/blockhosts-list-acl.squid" (j) deny_info
> ERR_URL_BLOCKED block_urls deny_info ERR_URL_BLOCKED
> block_urlpaths deny_info ERR_DOMAIN_BLOCKED block_domains_list 
> deny_info ERR_DOMAIN_BLOCKED block_domains_listex deny_info
> ERR_DOMAIN_BLOCKED block_domains_regex deny_info ERR_HOST_BLOCKED
> block_hosts_list http_access allow allow_urls http_access allow
> allow_urlpaths http_access allow allow_domains_list http_access
> allow allow_domains_regex http_access deny block_urls http_access
> deny block_urlpaths http_access deny block_domains_list http_access
> deny block_domains_listex http_access deny block_domains_regex 
> http_access deny block_hosts_list
> 
> (a), (b) look like this: 
> "^http:\/\/websupport\.wdc\.com\/sfclickcount.asp\?" (c), (d) look
> like this: "^\/cgi-bin\/" (e), (f), (g) look like this:
> "www.googletagmanager.com" (h), (i) look like this:
> "^banner(s)?[0-9]*\." (j) looks like this: "85.17.30.143"
> 
> (g) comes from a source like: e.g.
> http://winhelp2002.mvps.org/hosts.htm
> 
> On 15.10.2014 02:05, Mirza Dedic wrote:
>> Trying to understand what I am doing wrong with my ACLs (yes I've
>> read the ACL guide on squid site.. but still confused).. My
>> client is 172.16.10.101, trying to block access to facebook (and
>> other dstdomain file lists), but it is not working from the
>> client I can still access fb.
>> 
>> Is this because I have this rule below..?
>> 
>> acl localnet src 172.16.0.0/12 http_access allow localnet
>> 
> yes
> 
>> Instead of denying everything access and manually maintaining
>> rules, I want to allow http/https access for everything except
>> explicitly defined ACLs (in this case the facebook acl as a
>> test).
>> 
>> I've tried to set debugging to debug_options ALL,1 33,2 to see
>> more info on ACLs (read on some site this is the debug flags to
>> set) but I don't see any ACL details in my access.log file.
>> 
>> my squid.conf (for SQUID 3.3.3) file is below..
>> 
>> 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 8180 8443 563 1494 2598 8531 acl
>> Safe_ports port 80# http acl Safe_ports port 81 # http for
>> Pacific Brokerage acl Safe_ports port 21# ftp acl Safe_ports port
>> 443 563# http acl Safe_ports port 70# gopher acl Safe_ports port
>> 210# wais 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 Safe_ports port 8080 8081 8082 8088
>> 8180 acl Safe_ports port 3128 # Squid http server acl Safe_ports
>> port 1494 2598 # ICA - Citrix acl Safe_ports port 7000 8000 #
>> Oracle acl Safe_ports port 9000 # Oracle acl Safe_ports port
>> 8530# WSUS acl Safe_ports port 55905# WSUS acl Safe_ports port
>> 1025-65535# unregistered ports acl CONNECT method CONNECT
>> 
>> http_access allow localhost manager http_access deny manager 
>> http_access deny !Safe_ports http_access deny CONNECT !SSL_ports 
>> http_access deny to_localhost
>> 
>> *acl ads dstdomain "/etc/squid/blacklists/ads/domains"* *acl
>> adult dstdomain "/etc/squid/blacklists/adult/domains"* *acl
>> gambling dstdomain "/etc/squid/blacklists/gambling/domains"* *acl
>> fb dstdomain .facebook.com*
>> 
>> http_access allow localnet http_access allow localhost
>> 
>> *http_access deny ads adult gambling fb*
>> 
>> http_access deny all
>> 
>> http_port 8080 dns_nameservers 172.16.11.3 172.16.11.2
>> 172.16.11.1 visible_hostname www-proxy
>> 
>> hierarchy_stoplist cgi-bin ?
>> 
>> logformat oppy %ts.%03tu %6tr %>a %>A %Ss/%03>Hs %<st %rm %ru
>> %[un %Sh/%<a %mt access_log daemon:/var/log/squid/access.log
>> oppy cache_store_log daemon:/var/log/squid/store.log cache_log
>> /var/log/squid/cache.log cache_mem 64 MB logfile_rotate 4 
>> debug_options ALL,1 # ACL Debug Options # debug_options ALL,1
>> 33,2 # debug_options ALL,1 33,2 28,9 coredump_dir
>> /var/log/squid/squid
>> 
>> shutdown_lifetime 3 seconds dns_v4_first on retry_on_error on 
>> forward_max_tries 25 forward_timeout 30 seconds connect_timeout
>> 30 seconds read_timeout 30 seconds request_timeout 30 seconds 
>> persistent_request_timeout 1 minute
>> 
>> cache_dir ufs /var/cache/squid 100 16 256 cache_mgr
>> ittechs at domain.com
>> 
>> snmp_port 0 icp_port 0 htcp_port 0
>> 
>> refresh_pattern ^ftp:144020%10080 refresh_pattern
>> ^gopher:14400%1440 refresh_pattern -i (/cgi-bin/|\?) 00%0 
>> refresh_pattern .020%4320
>> 
>> 
>> _______________________________________________ squid-users
>> mailing list squid-users at lists.squid-cache.org 
>> http://lists.squid-cache.org/listinfo/squid-users
> 
> 
> 
> 
> _______________________________________________ squid-users mailing
> list squid-users at lists.squid-cache.org 
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