digest_file_auth man page

digest_file_auth — File based digest authentication helper for Squid.

Version 1.1


digest_file_auth [-c] file


digest_file_auth is an installed binary authentication program for Squid. It handles digest  authentication protocol and authenticates against a text file backend. This program will automatically detect the existence of a concurrency channel-ID and adjust appropriately. It may be used with any value 0 or above for the auth_param children concurrency= parameter.



Accept digest hashed passwords rather than plaintext in the password file


Username database file format:

- comment lines are possible and should start with a '#';

- empty or blank lines are possible;

- plaintext entry format is username:password

- HA1 entry format is username:realm:HA1

To build a directory integrated backend, you need to be able to calculate the HA1 returned to squid. To avoid storing a plaintext password you can calculate MD5(username:realm:password) when the user changes their password, and store the tuple username:realm:HA1. then find the matching username:realm when squid asks for the HA1.

This implementation could be improved by using such a triple for the file format.  However storing such a triple does little to improve security: If compromised the username:realm:HA1 combination is "plaintext equivalent" - for the purposes of digest authentication they allow the user access. Password synchronization is not tackled by digest - just preventing on the wire compromise.


This program was written by Robert Collins <robertc@squid-cache.org>

Based on prior work by Arjan de Vet <Arjan.deVet@adv.iae.nl> Jon Thackray <jrmt@uk.gdscorp.com>

This manual was written by Robert Collins <robertc@squid-cache.org> Amos Jeffries <amosjeffries@squid-cache.org>


Questions on the usage of this program can be sent to the Squid Users mailing list <squid-users@squid-cache.org>

Reporting Bugs

Bug reports need to be made in English. See http://wiki.squid-cache.org/SquidFaq/BugReporting for details of what you need to include with your bug report.

Report bugs or bug fixes using http://bugs.squid-cache.org/

Report serious security bugs to Squid Bugs <squid-bugs@squid-cache.org>

Report ideas for new improvements to the Squid Developers mailing list <squid-dev@squid-cache.org>

See Also

squid(8), GPL(7),
The Squid FAQ wiki http://wiki.squid-cache.org/SquidFaq
The Squid Configuration Manual http://www.squid-cache.org/Doc/config/