Provided by: nslcd_0.9.12-2_amd64 bug

NAME

       nslcd.conf - configuration file for LDAP nameservice daemon

DESCRIPTION

       The  nss-pam-ldapd package allows LDAP directory servers to be used as a primary source of
       name service information. (Name  service  information  typically  includes  users,  hosts,
       groups, and other such data historically stored in flat files or NIS.)

       The  file  nslcd.conf  contains  the  configuration  information  for  running  nslcd (see
       nslcd(8)).  The file contains options, one on each line, defining the way NSS lookups  and
       PAM actions are mapped to LDAP lookups.

OPTIONS

   RUNTIME OPTIONS
       threads NUM
              Specifies  the number of threads to start that can handle requests and perform LDAP
              queries.  Each thread opens a separate connection to the LDAP server.  The  default
              is to start 5 threads.

       uid UID
              This  specifies  the  user  id  with which the daemon should be run.  This can be a
              numerical id or a symbolic value.  If no uid is specified no attempt to change  the
              user  will  be  made.   Note  that  you  should  use values that don't need LDAP to
              resolve.

       gid GID
              This specifies the group id with which the daemon should be run.   This  can  be  a
              numerical  id or a symbolic value.  If no gid is specified no attempt to change the
              group will be made.  Note that you should  use  values  that  don't  need  LDAP  to
              resolve.

       log SCHEME [LEVEL]
              This  option  controls  the way logging is done.  The SCHEME argument may either be
              none, syslog or an  absolute  file  name.   The  LEVEL  argument  is  optional  and
              specifies  the  log  level.   The  log  level  may be one of: crit, error, warning,
              notice, info or debug. The default log  level  is  info.   All  messages  with  the
              specified  loglevel  or  higher  are  logged.  This option can be supplied multiple
              times.  If this option is omitted syslog info is assumed.

   GENERAL CONNECTION OPTIONS
       uri URI ...
              Specifies the LDAP URI of the server to connect to.  The URI scheme  may  be  ldap,
              ldapi  or ldaps, specifying LDAP over TCP, ICP or SSL respectively (if supported by
              the LDAP library).

              Alternatively, the value DNS may be used to try to lookup the server using DNS  SRV
              records.   By  default the current domain is used but another domain can be queried
              by using the DNS:DOMAIN syntax.  To convert  SRV  records  for  port  389  into  an
              ldaps:// URI, DNSLDAPS can be used.

              When  using  the  ldapi  scheme,  %2f  should  be  used  to  escape  slashes  (e.g.
              ldapi://%2fvar%2frun%2fslapd%2fldapi/), although most of the time this  should  not
              be needed.

              This  option  may  be  specified  multiple times and/or with more URIs on the line,
              separated by spaces. Normally,  only  the  first  server  will  be  used  with  the
              following servers as fall-back (see bind_timelimit below).

              If  LDAP  lookups  are  used  for  host  name  resolution, any host names should be
              specified as an IP address or name that can be resolved without using LDAP.

       ldap_version VERSION
              Specifies the version of the LDAP protocol to use.   The  default  is  to  use  the
              maximum version supported by the LDAP library.

       binddn DN
              Specifies  the  distinguished  name  with which to bind to the directory server for
              lookups.  The default is to bind anonymously.

       bindpw PASSWORD
              Specifies the credentials with which to bind.  This option is only applicable  when
              used  with  binddn  above.  If you set this option you should consider changing the
              permissions of the nslcd.conf file to only grant access to the root user.

       rootpwmoddn DN
              Specifies the distinguished name to use when the root user tries to modify a user's
              password using the PAM module.

              Note that currently this DN needs to exist as a real entry in the LDAP directory.

       rootpwmodpw PASSWORD
              Specifies  the  credentials  with  which to bind if the root user tries to change a
              user's password.  This option is only applicable when used with rootpwmoddn  above.
              If  this option is not specified the PAM module prompts the user for this password.
              If you set this  option  you  should  consider  changing  the  permissions  of  the
              nslcd.conf file to only grant access to the root user.

   SASL AUTHENTICATION OPTIONS
       sasl_mech MECHANISM
              Specifies the SASL mechanism to be used when performing SASL authentication.

       sasl_realm REALM
              Specifies the SASL realm to be used when performing SASL authentication.

       sasl_authcid AUTHCID
              Specifies   the   authentication   identity   to   be  used  when  performing  SASL
              authentication.

       sasl_authzid AUTHZID
              Specifies  the  authorization  identity   to   be   used   when   performing   SASL
              authentication.   Must  be specified in one of the formats: dn:<distinguished name>
              or u:<username>.

       sasl_secprops PROPERTIES
              Specifies Cyrus SASL security properties.  Allowed  values  are  described  in  the
              ldap.conf(5) manual page.

       sasl_canonicalize yes|no
              Determines  whether  the  LDAP server host name should be canonicalised. If this is
              set to yes the LDAP library will do a reverse host name lookup.  By default, it  is
              left up to the LDAP library whether this check is performed or not.

   KERBEROS AUTHENTICATION OPTIONS
       krb5_ccname NAME
              Set the name for the GSS-API Kerberos credentials cache.

   SEARCH/MAPPING OPTIONS
       base [MAP] DN
              Specifies  the  distinguished  name (DN) to use as search base.  This option may be
              supplied multiple times and all specified bases will be searched.

              A global search base may be specified or a MAP-specific one.   If  no  MAP-specific
              search bases are defined the global ones are used.

              If,  instead  of a DN, the value DOMAIN is specified, the host's DNS domain is used
              to construct a search base.  A value of "" can be used to indicate an empty  search
              base  (quotes  are  not otherwise supported for base values and not all LDAP server
              configurations support this).

              If this value is not defined an attempt is made to look it  up  in  the  configured
              LDAP  server.  If  the  LDAP  server  is unavailable during start-up nslcd will not
              start.

       scope [MAP] sub[tree]|one[level]|base|children
              Specifies the search scope (subtree, onelevel,  base  or  children).   The  default
              scope  is  subtree;  base  scope  is  almost never useful for name service lookups;
              children scope is not supported on all servers.

       deref never|searching|finding|always
              Specifies the policy for dereferencing aliases.  The default  policy  is  to  never
              dereference aliases.

       referrals yes|no
              Specifies  whether  automatic  referral  chasing  should  be  enabled.  The default
              behaviour is to chase referrals.

       filter MAP FILTER
              The FILTER is an LDAP search filter to use for a specific map.  The default  filter
              is a basic search on the objectClass for the map (e.g. (objectClass=posixAccount)).

       map MAP ATTRIBUTE NEWATTRIBUTE
              This option allows for custom attributes to be looked up instead of the default RFC
              2307 attributes.  The MAP may be one of the supported maps below.  The ATTRIBUTE is
              the  one  as  used  in  RFC  2307 (e.g. userPassword, ipProtocolNumber, macAddress,
              etc.).  The NEWATTRIBUTE may be any attribute as it is available in the directory.

              If the NEWATTRIBUTE is presented in quotes (") it is treated as an expression which
              will  be evaluated to build up the actual value used.  See the section on attribute
              mapping expressions below for more details.

              Only some attributes for group, passwd and shadow entries may  be  mapped  with  an
              expression  (because  other  attributes  may be used in search filters).  For group
              entries only the userPassword attribute may be  mapped  with  an  expression.   For
              passwd  entries  the  following  attributes  may  be  mapped  with  an  expression:
              userPassword, gidNumber, gecos, homeDirectory and loginShell.  For  shadow  entries
              the   following   attributes  may  be  mapped  with  an  expression:  userPassword,
              shadowLastChange, shadowMin, shadowMax, shadowWarning, shadowInactive, shadowExpire
              and shadowFlag.

              The  uidNumber  and gidNumber attributes in the passwd and group maps may be mapped
              to the objectSid followed by the domain SID to derive numeric user  and  group  ids
              from the SID (e.g. objectSid:S-1-5-21-3623811015-3361044348-30300820).

              By default all userPassword attributes are mapped to the unmatchable password ("*")
              to avoid accidentally leaking password information.

   TIMING/RECONNECT OPTIONS
       bind_timelimit SECONDS
              Specifies the time limit (in seconds) to  use  when  connecting  to  the  directory
              server.   This  is  distinct from the time limit specified in timelimit and affects
              the set-up of the connection only.  Note that not all LDAP  client  libraries  have
              support  for  setting  the  connection  time out.  The default bind_timelimit is 10
              seconds.

       timelimit SECONDS
              Specifies the time limit (in seconds) to wait for a response from the LDAP  server.
              A  value of zero (0), which is the default, is to wait indefinitely for searches to
              be completed.

       idle_timelimit SECONDS
              Specifies the period of inactivity (in seconds) after which the connection  to  the
              LDAP server will be closed.  The default is not to time out connections.

       reconnect_sleeptime SECONDS
              Specifies the number of seconds to sleep when connecting to all LDAP servers fails.
              By default 1 second is waited between the first failure and the first retry.

       reconnect_retrytime SECONDS
              Specifies the time after which the LDAP server  is  considered  to  be  permanently
              unavailable.   Once  this  time  is reached retries will be done only once per this
              time period.  The default value is 10 seconds.

       Note that the reconnect logic as described above is the mechanism  that  is  used  between
       nslcd  and  the LDAP server. The mechanism between the NSS and PAM client libraries on one
       end and nslcd on the other is simpler with a fixed compiled-in time out of  a  10  seconds
       for writing to nslcd and a time out of 60 seconds for reading answers.  nslcd itself has a
       read time out of 0.5 seconds and a write time out of 60 seconds.

   SSL/TLS OPTIONS
       ssl on|off|start_tls
              Specifies whether to use SSL/TLS or not (the default is not to).  If  start_tls  is
              specified then StartTLS is used rather than raw LDAP over SSL.  Not all LDAP client
              libraries support both SSL, StartTLS and all related configuration options.

       tls_reqcert never|allow|try|demand|hard
              Specifies what checks to perform on a server-supplied certificate.  The meaning  of
              the  values  is  described  in  the  ldap.conf(5)  manual  page.   At  least one of
              tls_cacertdir and tls_cacertfile is required if peer verification is enabled.

       tls_cacertdir PATH
              Specifies the directory containing  X.509  certificates  for  peer  authentication.
              This  parameter is ignored when using GnuTLS.  On Debian OpenLDAP is linked against
              GnuTLS.

       tls_cacertfile PATH
              Specifies the path to the X.509 certificate for peer authentication.

       tls_randfile PATH
              Specifies the path to an entropy source.  This  parameter  is  ignored  when  using
              GnuTLS.  On Debian OpenLDAP is linked against GnuTLS.

       tls_ciphers CIPHERS
              Specifies  the ciphers to use for TLS.  See your TLS implementation's documentation
              for further information.

       tls_cert PATH
              Specifies the path to the file containing the  local  certificate  for  client  TLS
              authentication.

       tls_key PATH
              Specifies  the  path  to  the  file  containing  the  private  key  for  client TLS
              authentication.

       tls_reqsan never|allow|try|demand|hard
              Specifies the way server Subject Alternative Name (SAN) is checked in  the  server-
              supplied  certificate.   The meaning of the values is described in the ldap.conf(5)
              manual page.

       tls_crlcheck none|peer|all
              Specifies if the Certificate Revocation List (CRL) of the  CA  should  be  used  to
              verify if the server certificates have not been revoked.  The meaning of the values
              is described in the ldap.conf(5) manual page.

       tls_crlfile PATH
              Specifies the path to the file containing a Certificate Revocation List to be  used
              to  verify  if  the server certificates.  The meaning of the values is described in
              the ldap.conf(5) manual page.

   OTHER OPTIONS
       pagesize NUMBER
              Set this to a number greater than 0 to request paged results from the  LDAP  server
              in accordance with RFC2696.  The default (0) is to not request paged results.

              This  is useful for LDAP servers that contain a lot of entries (e.g. more than 500)
              and limit the number of entries that are returned with one request.   For  OpenLDAP
              servers  you  may  need  to  set sizelimit size.prtotal=unlimited for allowing more
              entries to be returned over multiple pages.

       nss_initgroups_ignoreusers user1,user2,...
              This option prevents group membership lookups through LDAP for the specified users.
              This  can  be useful in case of unavailability of the LDAP server.  This option may
              be specified multiple times.

              Alternatively, the value ALLLOCAL may be used. With that value nslcd builds a  full
              list of non-LDAP users on startup.

       nss_min_uid UID
              This option ensures that LDAP users with a numeric user id lower than the specified
              value are ignored. Also requests for users with a lower user id are ignored.

       nss_uid_offset NUMBER
              This option specifies an offset that is added to all LDAP numeric user  ids.   This
              can  be  used to avoid user id collisions with local users or, when using objectSid
              attributes, for compatibility reasons.

              The value from the nss_min_uid option is evaluated after applying the offset.

       nss_gid_offset NUMBER
              This option specifies an offset that is added to all LDAP numeric group ids.   This
              can  be used to avoid user id collisions with local groups or, when using objectSid
              attributes, for compatibility reasons.

       nss_nested_groups yes|no
              If this option is set, the member attribute of a group may point to another  group.
              Members  of  nested  groups  are also returned in the higher level group and parent
              groups are returned when finding groups for a specific user.  The default is not to
              perform extra searches for nested groups.

       nss_getgrent_skipmembers yes|no
              If  this  option  is  set,  the  group member list is not retrieved when looking up
              groups.  Lookups for finding which groups a user belongs to will remain  functional
              so the user will likely still get the correct groups assigned on login.

              This  can  offer  a  speed-up  on  systems that have very large groups.  It has the
              downside of returning inconsistent information about  group  membership  which  may
              confuse some applications.  This option is not recommended for most configurations.

       nss_disable_enumeration yes|no
              If  this  option  is set, functions which cause all user/group entries to be loaded
              (getpwent(), getgrent(), setspent()) from the directory will not succeed  in  doing
              so.   Applications  that depend on being able to sequentially read all users and/or
              groups may fail to operate correctly.

              This can dramatically reduce LDAP server load in situations where there are a great
              number  of  users  and/or  groups.   This  is  typically  used  in situations where
              user/program access to enumerate the entire directory is undesirable, and  changing
              the  behavior  of the user/program is not possible.  This option is not recommended
              for most configurations.

       validnames REGEX
              This option can be used to specify how user and group names are verified within the
              system.  This  pattern is used to check all user and group names that are requested
              and returned from LDAP.

              The regular expression should be specified as a POSIX extended regular  expression.
              The  expression  itself  needs  to be separated by slash (/) characters and the 'i'
              flag may be appended at the  end  to  indicate  that  the  match  should  be  case-
              insensitive.      The     default     value    is    /^[a-z0-9._@$()]([a-z0-9._@$()
              \\~-]*[a-z0-9._@$()~-])?$/i

       ignorecase yes|no
              This specifies whether or not to perform  searches  for  group,  netgroup,  passwd,
              protocols,  rpc, services and shadow maps using case-insensitive matching.  Setting
              this to yes could open up the system to authorisation  bypass  vulnerabilities  and
              introduce  nscd cache poisoning vulnerabilities which allow denial of service.  The
              default is to perform case-sensitive filtering of LDAP search results for the above
              maps.

       pam_authc_ppolicy yes|no
              This  option  specifies  whether password policy controls are requested and handled
              from the LDAP server when performing user authentication.  By default the  controls
              are requested and handled if available.

       pam_authc_search FILTER
              By  default  nslcd  performs  an LDAP search with the user's credentials after BIND
              (authentication) to ensure that the BIND operation  was  successful.   The  default
              search is a simple check to see if the user's DN exists.

              A search filter can be specified that will be used instead.  The same substitutions
              as with the pam_authz_search option will be performed  and  the  search  should  at
              least return one entry.

              The value BASE may be used to force the default search for the user DN.

              The  value  NONE  may  be used to indicate that no search should be performed after
              BIND.  Note that some LDAP servers do not always return a correct error code  as  a
              result of a failed BIND operation (e.g. when an empty password is supplied).

       pam_authz_search FILTER
              This  option  allows flexible fine tuning of the authorisation check that should be
              performed. The search filter specified is executed and if any entries match, access
              is granted, otherwise access is denied.

              The  search  filter  can  contain  the  following  variable  references: $username,
              $service, $ruser, $rhost, $tty, $hostname, $fqdn, $domain, $dn,  and  $uid.   These
              references  are substituted in the search filter using the same syntax as described
              in the section on attribute mapping expressions below.

              For example, to check that the user has a proper  authorizedService  value  if  the
              attribute  is  present  (this  almost emulates the pam_check_service_attr option in
              PADL's pam_ldap):

              (&(objectClass=posixAccount)(uid=$username)(|(authorizedService=$service)(!(authorizedService=*))))

              The pam_check_host_attr option can be emulated with:

              (&(objectClass=posixAccount)(uid=$username)(|(host=$hostname)(host=$fqdn)(host=\\*)))

              This option may be specified multiple times and all specified  searches  should  at
              least return one entry for access to be granted.

       pam_password_prohibit_message "MESSAGE"
              If  this  option is set password modification using pam_ldap will be denied and the
              specified message will be presented to the user instead.  The message can  be  used
              to direct the user to an alternative means of changing their password.

       reconnect_invalidate DB,DB,...
              If  this  option  is  set, nslcd will try to flush the specified external caches on
              start-up and whenever a connection to the LDAP server is  re-established  after  an
              error.

              DB  can refer to one of the nsswitch maps, in which case nscd is contacted to flush
              its cache for the specified database.  If DB is nfsidmap, nfsidmap is contacted  to
              clear its cache.

              Using this option ensures that external caches are cleared of incorrect information
              (typically the absence of users) that may be present due to unavailability  of  the
              LDAP server.

       cache CACHE TIME [TIME]
              Configure the time entries are kept in the specified internal cache.

              The  first  TIME  value specifies the time to keep found entries in the cache.  The
              second TIME value specifies to the time to remember that a particular entry was not
              found.   If  the  second  parameter  is absent, it is assumed to be the same as the
              first.

              Time values are specified as a number followed by an s for seconds, m for  minutes,
              h for hours or d for days.  Use 0 or off to disable the cache.

              Currently,  only  the  dn2uid  cache  is  supported  that is used to remember DN to
              username lookups that are used when the member attribute is used.  The default time
              value for this cache is 15m.

SUPPORTED MAPS

       The following maps are supported. They are referenced as MAP in the options above.

       alias[es]
              Mail  aliases.   Note  that  most  mail  servers  do  not use the NSS interface for
              requesting mail aliases and parse /etc/aliases on their own.

       ether[s]
              Ethernet numbers (mac addresses).

       group  Posix groups.

       host[s]
              Host names.

       netgroup
              Host and user groups used for access control.

       network[s]
              Network numbers.

       passwd Posix users.

       protocol[s]
              Protocol definitions (like in /etc/protocols).

       rpc    Remote procedure call names and numbers.

       service[s]
              Network service names and numbers.

       shadow Shadow user password information.

ATTRIBUTE MAPPING EXPRESSIONS

       For some attributes a mapping expression may be used to  construct  the  resulting  value.
       This  is  currently  only  possible  for  attributes that do not need to be used in search
       filters.  The expressions are a subset of the double  quoted  string  expressions  in  the
       Bourne (POSIX) shell.  Instead of variable substitution, attribute lookups are done on the
       current entry and the attribute value  is  substituted.   The  following  expressions  are
       supported:

       ${attr} (or $attr for short)
              will substitute the value of the attribute

       ${attr:-word}
              (use  default)  will  substitute the value of the attribute or, if the attribute is
              not set or empty substitute the word

       ${attr:+word}
              (use alternative) will substitute word if attribute is  set,  otherwise  substitute
              the empty string

       ${attr:offset:length}
              will  substitute  length  characters (actually bytes) starting from position offset
              (which is counted starting at zero); the substituted string is truncated if  it  is
              too  long;  in  particular,  it  can be of length zero (if length is zero or offset
              falls out of the original string)

       ${attr#word}
              remove the shortest possible match of word from the left of the attribute value

       ${attr##word}
              remove the longest possible match of word from the  left  of  the  attribute  value
              (pynslcd only)

       ${attr%word}
              remove  the  shortest  possible match of word from the right of the attribute value
              (pynslcd only)

       ${attr%%word}
              remove the longest possible match of word from the right  of  the  attribute  value
              (pynslcd only)

       Only  the # matching expression is supported in nslcd and only with the ? wildcard symbol.
       The pynslcd implementation supports full matching.

       Quote ("), dollar ($) and backslash (\) characters should be escaped with a backslash (\).

       The expressions are inspected to automatically fetch the appropriate attributes from LDAP.
       Some examples to demonstrate how these expressions may be used in attribute mapping:

       "${shadowFlag:-0}"
              use the shadowFlag attribute, using the value 0 as default

       "${homeDirectory:-/home/$uid}"
              use the uid attribute to build a homeDirectory value if that attribute is missing

       "${isDisabled:+100}"
              if the isDisabled attribute is set, return 100, otherwise leave value empty

       "${userPassword#{crypt\}}"
              strip  the  {crypt}  prefix from the userPassword attribute, returning the raw hash
              value

FILES

       /etc/nslcd.conf
              the main configuration file

       /etc/nsswitch.conf
              Name Service Switch configuration file

SEE ALSO

       nslcd(8), nsswitch.conf(5)

AUTHOR

       This manual was written by Arthur de Jong <arthur@arthurdejong.org> and is  based  on  the
       nss_ldap(5) manual developed by PADL Software Pty Ltd.