NAME
squid_ldap_group - Squid LDAP external acl group helper
SYNOPSIS
squid_ldap_group -b "base DN" -f "LDAP search filter" [options]
[ldap_server_name[:port]|URI]...
DESCRIPTION
This helper allows Squid to connect to a LDAP directory to authorize
users via LDAP groups. LDAP options are specified as parameters on the
command line, while the username(s) and group(s) to be checked against
the LDAP directory are specified on subsequent lines of input to the
helper, one username/group pair per line separated by a space.
As expected by the external_acl construct of Squid, after specifying a
username and group followed by a new line, this helper will produce
either OK or ERR on the following line to show if the user is a member
of the specified group.
The program operates by searching with a search filter based on the
users user name and requested group, and if a match is found it is
determined that the user belongs to the group.
-b basedn (REQUIRED)
Specifies the base DN under which the groups are located.
-B basedn
Specifies the base DN under which the users are located (if
different)
-g Specifies that the first query argument sent to the helper by
Squid is a extension to the basedn and will be temporarily added
in front of the global basedn for this query.
-f filter
LDAP search filter used to search the LDAP directory for any
matching group memberships. In the filter %u will be replaced
by the user name (or DN if the -F or -u options are used) and %g
by the requested group name.
-F filter
LDAP search filter used to search the LDAP directory for any
matching users. In the filter %s will be replaced by the user
name. If % is to be included literally in the filter then use
%%.
-u attr
LDAP attribute used to construct the user DN from the user name
and base dn without needing to search for the user.
-s base|one|sub
search scope. Defaults to 'sub'.
base object only, one level below the base object or subtree
below the base object
-D binddn -w password
The DN and password to bind as while performing searches.
Required if the directory does not allow anonymous searches.
As the password needs to be printed in plain text in your Squid
configuration and will be sent on the command line to the helper
it is strongly recommended to use a account with minimal
associated privileges. This to limit the damage in case someone
could get hold of a copy of your Squid configuration file or
extracts the password used from a process listing.
-D binddn -W secretfile
The DN and the name of a file containing the password to bind as
while performing searches.
Less insecure version of the former parameter pair with two
advantages: The password does not occur in the process listing,
and the password is not being compromised if someone gets the
squid configuration file without getting the secretfile.
-P Use a persistent LDAP connection. Normally the LDAP connection
is only open while verifying a users group membership to
preserve resources at the LDAP server. This option causes the
LDAP connection to be kept open, allowing it to be reused for
further user validations. Recommended for larger installations.
-R do not follow referrals
-a never|always|search|find
when to dereference aliases. Defaults to 'never'
never dereference aliases (default), always dereference aliases,
only while searching or only to find the base object
-H ldapuri
Specity the LDAP server to connect to by a LDAP URI (requires
OpenLDAP libraries)
-h ldapserver
Specify the LDAP server to connect to
-p ldapport
Specify an alternate TCP port where the ldap server is listening
if other than the default LDAP port 389.
-v 2|3 LDAP protocol version. Defaults to 3 if not specified.
-Z Use TLS encryption
-Ecertpath
Enable LDAP over SSL (requires Netscape LDAP API libraries)
-cconnect_timeout
Specify timeout used when connecting to LDAP servers (requires
Netscape LDAP API libraries)
-tsearch_timeout
Specify time limit on LDAP search operations
-S Strip NT domain name component from user names (/ or \
separated)
-K Strip Kerberos Realm component from user names (@ separated)
-d Debug mode where each step taken will get reported in detail.
Useful for understanding what goes wrong if the results is not
what is expected.
SQUID CONFIGURATION
This helper is intended to be used as a external_acl_type helper from
squid.conf.
external_acl_type ldap_group %LOGIN /path/to/squid_ldap_group ...
acl group1 external ldap_group Group1
acl group2 external ldap_group Group2
NOTES
When constructing search filters it is recommended to first test the
filter using ldapsearch before you attempt to use squid_ldap_group.
This to verify that the filter matches what you expect.
AUTHOR
This manual page was written by Henrik Nordstrom <hno@marasystems.com>
squid_ldap_group is written by Flavio Pescuma <flavio@marasystems.com>
and Henrik Nordstrom <hno@squid-cache.org>, based on prior work in
squid_ldap_auth by Glen Newton <glen.newton@nrc.ca>
KNOWN LIMITATIONS
Max 16 occurrences of %s in the -u argument is supported.
QUESTIONS
Any questions on usage can be sent to Squid Users <squid-users@squid-
cache.org>, or to your favorite LDAP list/friend if the question is
more related to LDAP than Squid.
REPORTING BUGS
Report bugs or bug-fixes to Squid Bugs <squid-bugs@squid-cache.org> or
ideas for new improvements to Squid Developers <squid-dev@squid-
cache.org>
SEE ALSO
squid_ldap_auth(8), ldapsearch(1),
Your favorite LDAP documentation
RFC2254 - The String Representation of LDAP Search Filters,