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,