Provided by: libnss-ldap_264-2ubuntu2_i386 bug

NAME

       nss_ldap - LDAP nameservice provider

DESCRIPTION

       The nss_ldap module is a set of C library extensions which allows X.500
       and 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.)

       Features  of  the PADL nss_ldap module include support for both the RFC
       2307 and RFC 2307bis schema, a common  implementation  across  multiple
       platforms,  Kerberos and SSL security, configurable schema mapping, and
       configuration file compatibility with the pam_ldap(5) module.

       Because LDAP is a hierarchical directory service,  one  can  distribute
       the  information  in  a manner which reflects organizational structure.
       This contrasts with the flat, single domain policy  of  NIS.  LDAP  has
       many  of  the advantages of NIS+ (security and scalability) without the
       complexity.

       nss_ldap will work alongside existing NIS, NIS+, DNS and flat file name
       services.  More  importantly, because it builds as a shared library, it
       is not necessary to recompile any applications  to  take  advantage  of
       LDAP.

       The  present  version of nss_ldap supports AIX 4.3.3 and above, FreeBSD
       5.1, HP-UX 11i, Linux and Solaris 2.6 and above. Many  vendors  provide
       their  own LDAP nameservice providers, often also called nss_ldap. This
       manual page applies to the PADL nss_ldap module only. If you are  using
       a vendor provided module, consult the relevant documentation instead.

       The features supported by the version of nss_ldap depend on which flags
       were enabled when the software was built. Most features are enabled  in
       the   configuration   file,  described  below.  (The  location  of  the
       configuration file is configurable at compile time; the default path is
       /etc/ldap.conf.)   Also,  some  features  may be unavailable on certain
       operating systems or with certain LDAP libraries. For more information,
       consult your vendor.

CONFIGURATION

       nss_ldap  stores  its configuration in the ldap.conf file, the location
       of which is configurable at compile time.  (It  should  be  noted  that
       some  LDAP client libraries, such as OpenLDAP, also use a configuration
       file  of  the  same  name.   nss_ldap  supports  many   of   the   same
       configuration  file  options  as OpenLDAP, but it adds several that are
       specific to the functionality it provides.   Additionally,  it  is  not
       guaranteed  that nss_ldap will continue to match the configuration file
       semantics of OpenLDAP.  You may wish to use different files.)

       Configuration file options consist of a keyword followed by a space and
       any arguments. The following options are supported by both nss_ldap and
       the PADL pam_ldap module:

       host <name:port ...>
              Specifies the name(s) or IP address(es) of the LDAP server(s) to
              connect  to.  In  the  case  that nss_ldap is used for host name
              resolution, each server should be specified as an IP address  or
              name  that can be resolved without using LDAP.  Multiple servers
              may be specified, each separated by a space.  The failover  time
              depends on whether the LDAP client library supports configurable
              network or connect timeouts (see bind_timelimit below).

       base <base>
              Specifies the default base distinguished name (DN)  to  use  for
              searches.

       uri <ldap[is]://[name[:port]] ...>
              For  LDAP client libraries that support it, specifies the URI(s)
              of the LDAP server(s) to connect to. The URI scheme may be ldap,
              ldapi,   or  ldaps,  specifying  LDAP  over  TCP,  IPC  and  SSL
              respectively. If applicable, a port number can be specified; the
              default  port  number  for  the  selected  protocol  is  used if
              omitted. This option takes precedence over the host  option;  it
              is not possible to combine the two.

       ldap_version <version>
              Specifies  the  version  of  the LDAP protocol to use. Presently
              version must be 2 or 3.  The  default  is  to  use  the  maximum
              version supported by the client library.

       binddn <binddn>
              Specifies  the  distinguished  name  with  which  to bind to the
              directory server(s). This option is optional; the default is  to
              bind anonymously.

       bindpw <bindpw>
              Specifies  the  cleartext  credentials  with which to bind. This
              option is only applicable  when  used  with  binddn  above.  The
              default  is  no credential (anonymous bind). When binding to the
              directory using SASL or other  authentication  mechanisms  apart
              from simple binds, this option is not used.

       rootbinddn <binddn>
              This  option has the same syntax and effect as the binddn option
              above, except it applies when the effective user ID is zero.  If
              not  specified,  then  the  identity specified in binddn is used
              instead. Because the configuration file may be readable by  many
              users,   the   root  bind  DN  credentials  are  stored  in  the
              ldap.secret file instead. This  file  is  usually  in  the  same
              directory as the configuration file.

       port <port>
              Specifies  the  port to connect to; this option is used with the
              host option, and is ignored with the uri option.

       scope <sub|one|base>
              Specifies the search scope (subtree, one level or base  object).
              The  default scope is subtree; base scope is almost never useful
              for nameservice lookups.

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

       timelimit <timelimit>
              Specifies  the  time  limit  (in seconds) to use when performing
              searches. A value of zero (0), which is the default, is to  wait
              indefinitely for searches to be completed.

       bind_timelimit <timelimit>
              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 initial server connection
              only. (Server connections are otherwise cached.) Only some  LDAP
              client  libraries have the underlying functionality necessary to
              support this option. The default bind timelimit is 30 seconds.

       referrals <yes|no>
              Specifies whether automatic referral chasing should be  enabled.
              The default behaviour is specifed by the LDAP client library.

       restart <yes|no>
              Specifies  whether  the  LDAP client library should restart the
              select(2) system call when  interrupted.  This  feature  is  not
              supported by all client libraries.

       logdir <directory>
              Specifies  the  directory  used  for  logging by the LDAP client
              library. This feature is not supported by all client  libraries.

       debug <level>
              Specifies  the  debug  level used for logging by the LDAP client
              library. This feature is not supported by all client  libraries,
              and  does  not  apply  to  the  nss_ldap  and  pam_ldap  modules
              themselves (debugging, if  any,  is  configured  separately  and
              usually at compile time).

       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
              and StartTLS, and all related configuration options.

       sslpath <cert7_path>
              For the Netscape and Mozilla LDAP client  libraries  only,  this
              specifies the path to the X.509 certificate database.

       tls_checkpeer <yes|no>
              Specifies  whether  to require and verify the server certificate
              or not, when using SSL/TLS with  the  OpenLDAP  client  library.
              The  default  is  to  use  the  default  behaviour of the client
              library; for OpenLDAP 2.0 and earlier it is "no",  for  OpenLDAP
              2.1  and  later  it  is "yes". At least one of tls_cacertdir and
              tls_cacertfile is required if peer verification is enabled.

       tls_cacertdir <certificate_dir>
              Specifies the directory containing X.509 certificates  for  peer
              authentication.

       tls_cacertfile <certificate_file>
              Specifies   the   path   to   the  X.509  certificate  for  peer
              authentication.

       tls_randfile <entropy_file>
              Specifies the path to an entropy source.

       tls_ciphers <ciphers>
              Specifies  the  ciphers  to  use   for   TLS.   See   your   TLS
              implementation’s documentation for further information.

       tls_cert <certificate_file>
              Specifies  the path to the file containing the local certificate
              for client TLS authentication.

       tls_key <key_file>
              Specifies the path to the file containing the  private  key  for
              client TLS authentication.

       The following configuration options apply to nss_ldap only:

       bind_policy <hard_open|hard_init|soft>
              Specifies  the  policy to use for reconnecting to an unavailable
              LDAP server. The  default  is  hard_open,  which  reconnects  if
              opening  the  connection  to  the  directory  server  failed. By
              contrast, hard_init reconnects if  initializing  the  connection
              failed.  Initializing  may  not  actually  contact the directory
              server, and it is possible that a malformed  configuration  file
              will  trigger  reconnection. If soft is specified, then nss_ldap
              will return immediately on server failure. All "hard"  reconnect
              policies block with exponential backoff before retrying.

       nss_connect_policy <persist|oneshot>
              Determines whether nss_ldap persists connections. The default is
              for the connection to the LDAP server to remain open  after  the
              first request.

       idle_timelimit <timelimit>
              Specifies  the time (in seconds) after which nss_ldap will close
              connections to the directory server. The default is not to  time
              out connections.

       sasl_authid <authid>
              Specifies  the authorization identity to be used when performing
              SASL authentication.

       rootsasl_auth_id <authid>
              Specifies the authorization identity to be used when  performing
              SASL  authentication  as  root  (when  the  effective user ID is
              zero).

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

       rootuse_sasl <yes|no>
              Specifies  whether  SASL  authentication should be used when the
              effective user ID is zero.

       krb5_ccname <PREFIX:args>
              If nss_ldap is built with configurable GSS-API credentials cache
              name support, specifies the Kerberos credentials cache to use.

       nss_paged_results <yes|no>
               Enables support for paged results.

       pagesize <pagesize>
              When paged results are enabled (see above), specifies the number
              of entries to return in a single page. The default is 1000.

       nss_base_<map> <basedn?scope?filter>
              Specify the search  base,  scope  and  filter  to  be  used  for
              specific  maps.  (Note  that map forms part of the configuration
              file keyword  and  is  one  of  passwd,  shadow,  group,  hosts,
              services,    networks,   protocols,   rpc,   ethers,   netmasks,
              bootparams, aliases and netgroup.)  The  syntax  of  basedn  and
              scope  are the same as for the configuration file options of the
              same name, with the addition of being able to omit the  trailing
              suffix  of the base DN (in which case the global base DN will be
              appended instead).  The filter is a search filter to be added to
              the  default  search  filter  for  a specific map, such that the
              effective filter is the logical intersection  of  the  two.  The
              base  DN,  scope  and filter are separated with literal question
              marks (?) as given above; this is for compatibility with the DUA
              configuration  profile  schema  and  the  ldapprofile tool. This
              option may be specified multiple times.

       nss_map_attribute <from_attribute> <to_attribute>
              This  option  may  be  specified  multiple  times,  and  directs
              nss_ldap  to  use  the attribute to_attribute instead of the RFC
              2307 attribute from_attribute in all lookups.  If  nss_ldap  was
              built  without  schema  mapping  support,  then  this  option is
              ignored.

       nss_map_objectclass <from_objectclass> <to_objectclass>
              This  option  may  be  specified  multiple  times,  and  directs
              nss_ldap  to  use the object class to_objectclass instead of the
              RFC 2307 object  class  from_objectclass  in  all  lookups.   If
              nss_ldap  was  built  without  schema mapping support, then this
              option is ignored.

       nss_default_attribute_value <attribute> <value>
              Specifies the default value to use for  entries  that  lack  the
              specified  attribute.  This  option  may  be  specified multiple
              times, for different attributes.  If nss_ldap was built  without
              schema mapping support, then this option is ignored.

       nss_override_attribute_value <attribute> <value>
              Specifies  a  value  to  use  for  the  specified  attribute  in
              preference to that contained in the actual  entry.  This  option
              may  be  specified multiple times, for different attributes.  If
              nss_ldap was built without schema  mapping  support,  then  this
              option is ignored.

       nss_schema <rfc2307bis|rfc2307>
              If  the value of this option is  rfc2307bis then support for the
              RFC2307bis  schema  (distinguished  names  in  groups)  will  be
              enabled.

       nss_initgroups <backlink>
              This option directs the nss_ldap implementation of initgroups(3)
              to determine a user’s group membership by reading  the  memberOf
              attribute  of  their directory entry (and of any nested groups),
              rather than querying on uniqueMember. This may provide increased
              performance  with  certain  directory servers that have peculiar
              indexing configurations.  If  RFC2307bis  support  is  disabled,
              then this option is ignored.

       nss_initgroups_ignoreusers <user1,user2,...,userN>
              This option directs the nss_ldap implementation of initgroups(3)
              to return NSS_STATUS_NOTFOUND if called with a listed  users  as
              its argument.

       nss_getgrent_skipmembers <yes|no>
              Specifies  whether  or  not  to populate the members list in the
              group structure for group lookups.  If  very  large  groups  are
              present,  enabling this option will greatly increase perforance,
              at the cost of some lost functionality.  You  should  verify  no
              local applications rely on this information before enabling this
              on a production system.

       nss_srv_domain <domain>
              This option determines the DNS domain used  for  performing  SRV
              lookups.

AUTHOR

       The   nss_ldap   module   was   developed  by  PADL  Software  Pty  Ltd
       (www.padl.com).

FILES

       /etc/ldap.conf, /etc/ldap.secret, /etc/nsswitch.conf

SEE ALSO

       nsswitch.conf(5)

                                                                   nss_ldap(5)