The default installation of Squid on Ubuntu 12.04 does not support SSL. To enable SSL, it must be recompiled. This guide will walk you through compiling Squid on Ubuntu 12.04 to add SSL support. Although we are targeting Ubuntu 12.04, this guide will also work on Ubuntu 14.

Compile Squid

Install dependencies.

cd ~ 
mkdir squid_src 
cd squid_src 
sudo apt-get install build-essential fakeroot devscripts gawk gcc-multilib dpatch 
sudo apt-get build-dep squid3 
sudo apt-get build-dep openssl 
sudo apt-get source squid3 
sudo apt-get install libssl-dev 
sudo apt-get install openssl 

Change the default compiler options to include SSL support.

vi squid3-3.1.19/debian/rules

... add these rules to "DEB_CONFIGURE_EXTRA_FLAGS":

DEB_CONFIGURE_EXTRA_FLAGS := --datadir=/usr/share/squid3 \ 
        --sysconfdir=/etc/squid3 \ 
        --mandir=/usr/share/man \ 
        --with-cppunit-basedir=/usr \ 
        --enable-inline \ 
        --enable-ssl \  

Compile.

cd squid3-3.1.19/ 
debuild -us -uc -b 

Install it. The compiled file exists in the squid_src directory.

cd .. 
sudo dpkg -i squid3_3.1.19-1ubuntu3.12.04.2_amd64.deb squid3-common_3.1.19-1ubuntu3.12.04.2_all.deb squid3-dbg_3.1.19-1ubuntu3.12.04.2_amd64.deb 

Test whether or not the compiled version supports SSL. If you see the “enable – SSL” output, then the compile was successful.

squid3 -v |grep enable-ssl

Configure SSL and start Squid

Generate a self-signed certificate.

openssl req -new -keyout key.pem -nodes -x509 -days 365 -out cert.pem 

Move the server certificate to the squid3 configuration directory.

sudo mv cert.pem /etc/squid3/cert.pem
sudo mv key.pem /etc/squid3/key.pem

Enable HTTPS and specify the certificate.

sudo vi /etc/squid3/squid.conf 

... add this line:

https_port 443 cert=/etc/squid3/cert.pem key=/etc/squid3/key.pem 

Verify that the configuration file is formatted properly.

squid3 -k parse 

Run the Squid service.

sudo service squid3 restart

Setup is complete. Squid 3 will now be working with HTTPS. Enjoy.