squid_ldap_group(8)                                                                                          squid_ldap_group(8)



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 speci-
       fied 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 tem-
              porarily 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 member-
              ship 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 <hnoATmarasystems.com>

       squid_ldap_group is written by Flavio Pescuma <flavioATmarasystems.com> and Henrik Nordstrom <hnoATsquid-cache.org>,  based
       on prior work in squid_ldap_auth by Glen Newton <glen.newtonATnrc.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-usersATsquid-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-bugsATsquid-cache.org> or ideas for new  improvements  to  Squid  Developers
       <squid-devATsquid-cache.org>

SEE ALSO
       squid_ldap_auth(8), ldapsearch(1),
       Your favorite LDAP documentation
       RFC2254 - The String Representation of LDAP Search Filters,



Version 2.17                                             30 January 2005                                     squid_ldap_group(8)