Squid Splash Page Notes

I’m playing with Squid and setting it up as a captive portal.
This is my notes on their documentation.

  • Top-down processing of rules gave me 90% of the troubles I encountered.
  • The deny_info path doesn’t really work. It should be a filename relative to the error_directory directory.
  • You have to manually create the session db/session folder the first time. mkdir /var/lib/squid/session && chmod 777 /var/lib/squid/session
  • To clear sessions from the server (for testing), you can delete and re-create the sessions folder: rm /var/lib/squid/session -r && mkdir /var/lib/squid/session -r && chmod 777 /var/lib/squid/session
  • Always check permissions.

Next things to do:

  • Making it a transparent proxy
  • Dealing with SSL (port 443)
  • Changing upstream providers from LAN to USB Dongle

http://www.andybev.com/index.php/Setting_up_a_captive_portal_from_scratch_using_Debian
http://system-admin.xtronix.in/2012/07/captive-portal-with-transparent-proxy.html
https://wiki.archlinux.org/index.php/squid#Installation

Here’s a copy of my squid.conf:

#
# Recommended minimum configuration:
#

# Example rule allowing access from your local networks.
# Adapt to list your (internal) IP networks from where browsing
# should be allowed
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

#
# Recommended minimum Access Permission configuration:
#
# Deny requests to certain unsafe ports
http_access deny !Safe_ports

# Deny CONNECT to other than secure SSL ports
http_access deny CONNECT !SSL_ports

# Only allow cachemgr access from localhost
http_access allow localhost manager
http_access deny manager

# We strongly recommend the following be uncommented to protect innocent
# web applications running on the proxy server who think the only
# one who can access services on “localhost” is a local user
#http_access deny to_localhost

#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#

# Squid normally listens to port 3128
# http_port 3128 transparent
# http_port 80 vhost
# http_port 3128 intercept
http_port 3128 intercept

error_directory /makubex

# http://wiki.squid-cache.org/ConfigExamples/Portal/Splash
#### Passive ####

# external_acl_type splash_page ttl=60 concurrency=100 %SRC /usr/lib/squid/ext_session_acl -t 7200 -b /var/lib/squid/session.db
# acl existing_users external splash_page
# http_access deny !existing_users
# deny_info 511:splash.html existing_users

#### Active ####

# external_acl_type session ttl=300 negative_ttl=0 children-startup=1 concurrency=200 %LOGIN /usr/lib/squid/ext_session_acl
# acl session_login external session LOGIN
# http_access deny !session
# deny_info http://rystraum.com?url=%s session

external_acl_type session concurrency=100 ttl=3 %SRC /usr/lib/squid/ext_session_acl -a -T 10800 -b /var/lib/squid/session/
acl session_login external session LOGIN
external_acl_type session_active_def concurrency=100 ttl=3 %SRC /usr/lib/squid/ext_session_acl -a -T 10800 -b /var/lib/squid/session/
acl session_is_active external session_active_def
# acl clicked_login_url url_regex -i http://rystraum.com$
acl clicked_login_url url_regex -i http://rystraum.com/search$
http_access allow clicked_login_url session_login
http_access deny !session_is_active
deny_info 511:index.html session_is_active
# deny_info http://10.1.0.1?url=%s session_is_active
# acl clicked_login_url url_regex -i http://google.com$

##### Catch All #####

# Example rule allowing access from your local networks.
# Adapt localnet in the ACL section to list your (internal) IP networks
# from where browsing should be allowed
http_access allow localnet
http_access allow localhost

# And finally deny all other access to this proxy
http_access deny all

# Uncomment and adjust the following to add a disk cache directory.
#cache_dir ufs /var/cache/squid 256 16 256

# Leave coredumps in the first cache dir
coredump_dir /var/cache/squid

#
# Add any of your own refresh_pattern entries above these.
#
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 makubex