Ubuntu Manpage: ext_ldap_group_acl - Squid LDAP external acl group helper

Provided by: squid-openssl_5.9-0ubuntu0.22.04.2_amd64

NAME

       ext_ldap_group_acl - Squid LDAP external acl group helper

       Version 2.18

SYNOPSIS

       ext_ldap_group_acl -b base-DN -f filter [ options ] [ server [ ':' port ] | URI ] ...

DESCRIPTION

       ext_ldap_group_acl 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_type 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.

OPTIONS

-a never|always|search|find
When to dereference aliases. Defaults to 'never'

never dereference aliases (default), always dereference aliases, only during a
search or only to find the base object

-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)

-c connect_timeout
Specify timeout used when connecting to LDAP servers (requires Netscape LDAP
API libraries)

-d Debug mode where each step taken will get reported in detail. Useful for
understanding what goes wrong if the result is not what was expected.

-D binddn -w password
The DN and password to bind as while performing searches. Required if the LDAP
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.

-E certpath Enable LDAP over SSL (requires Netscape LDAP API libraries)

-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 %%

-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.

-h ldapserver
Specify the LDAP server to connect to

-H ldapuri Specify the LDAP server to connect to by a LDAP URI (requires OpenLDAP
libraries)

-K Strip Kerberos Realm component from user names (@ separated)

-p ldapport Specify an alternate TCP port where the LDAP server is listening if other than
the default LDAP port 389.

-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

-s base|one|sub
search scope. Defaults to sub

base object only,

one level below the base object or

subtree below the base object

-S Strip NT domain name component from user names (/ or \ separated)

-t search_timeout
Specify time limit on LDAP search operations

-u attr LDAP attribute used to construct the user DN from the user name and base dn
without needing to search for the user. A maximum of 16 occurrences of %s are
supported.

-v 2|3 LDAP protocol version. Defaults to 3 if not specified.

-Z Use TLS encryption

CONFIGURATION

       This helper is intended to be used as an external_acl_type helper in squid.conf .
              external_acl_type ldap_group %LOGIN /path/to/ext_ldap_group_acl ...
              acl group1 external ldap_group Group1
              acl group2 external ldap_group Group2

       NOTE: When constructing search filters it is recommended to first test  the  filter  using
       ldapsearch  to  verify  that  the filter matches what you expect before you attempt to use
       ext_ldap_group_acl

AUTHOR

       This program was written  by  Flavio  Pescuma  <flavio@marasystems.com>  Henrik  Nordstrom
       <hno@squid-cache.org>

       Based on prior work in squid_ldap_auth by Glen Newton <glen.newton@nrc.ca>

       This manual was written by Henrik Nordstrom <hno@marasystems.com>

COPYRIGHT

        * Copyright (C) 1996-2023 The Squid Software Foundation and contributors
        *
        * Squid software is distributed under GPLv2+ license and includes
        * contributions from numerous individuals and organizations.
        * Please see the COPYING and CONTRIBUTORS files for details.

       This program and documentation is copyright to the authors named above.

       Distributed under the GNU General Public License (GNU GPL) version 2 or later (GPLv2+).

QUESTIONS

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

       Or contact your favorite LDAP list/friend if the question is more  related  to  LDAP  than
       Squid.

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@lists.squid-cache.org>

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