ldap.conf(5)
NAME
ldap.conf, .ldaprc - LDAP configuration file/environment variables
SYNOPSIS
/etc/ldap/ldap.conf, ldaprc, .ldaprc, $LDAP<option-name>
DESCRIPTION
If the environment variable LDAPNOINIT is defined, all defaulting is
disabled.
The ldap.conf configuration file is used to set system-wide defaults to
be applied when running ldap clients.
Users may create an optional configuration file, ldaprc or .ldaprc, in
their home directory which will be used to override the system-wide
defaults file. The file ldaprc in the current working directory is
also used.
Additional configuration files can be specified using the LDAPCONF and
LDAPRC environment variables. LDAPCONF may be set to the path of a
configuration file. This path can be absolute or relative to the
current working directory. The LDAPRC, if defined, should be the
basename of a file in the current working directory or in the user's
home directory.
Environmental variables may also be used to augment the file based
defaults. The name of the variable is the option name with an added
prefix of LDAP. For example, to define BASE via the environment, set
the variable LDAPBASE to the desired value.
Some options are user-only. Such options are ignored if present in the
ldap.conf (or file specified by LDAPCONF).
Thus the following files and variables are read, in order:
variable $LDAPNOINIT, and if that is not set:
system file /etc/ldap/ldap.conf,
user files $HOME/ldaprc, $HOME/.ldaprc, ./ldaprc,
system file $LDAPCONF,
user files $HOME/$LDAPRC, $HOME/.$LDAPRC, ./$LDAPRC,
variables $LDAP<uppercase option name>.
Settings late in the list override earlier ones.
SYNTAX
The configuration options are case-insensitive; their value, on a case
by case basis, may be case-sensitive.
Blank lines are ignored.
Lines beginning with a hash mark (`#') are comments, and ignored.
Valid lines are made of an option's name (a sequence of non-blanks,
conventionally written in uppercase, although not required), followed
by a value. The value starts with the first non-blank character after
the option's name, and terminates at the end of the line, or at the
last sequence of blanks before the end of the line. The tokenization
of the value, if any, is delegated to the handler(s) for that option,
if any. Quoting values that contain blanks may be incorrect, as the
quotes would become part of the value. For example,
# Wrong - erroneous quotes:
URI "ldap:// ldaps://"
# Right - space-separated list of URIs, without quotes:
URI ldap:// ldaps://
# Right - DN syntax needs quoting for Example, Inc:
BASE ou=IT staff,o="Example, Inc",c=US
# or:
BASE ou=IT staff,o=Example2C Inc,c=US
# Wrong - comment on same line as option:
DEREF never # Never follow aliases
A line cannot be longer than LINE_MAX, which should be more than 2000
bytes on all platforms. There is no mechanism to split a long line on
multiple lines, either for beautification or to overcome the above
limit.
OPTIONS
The different configuration options are:
URI <ldap[si]://[name[:port]] ...>
Specifies the URI(s) of an LDAP server(s) to which the LDAP
library should connect. The URI scheme may be any of ldap,
ldaps or ldapi, which refer to LDAP over TCP, LDAP over SSL
(TLS) and LDAP over IPC (UNIX domain sockets), respectively.
Each server's name can be specified as a domain-style name or an
IP address literal. Optionally, the server's name can followed
by a ':' and the port number the LDAP server is listening on.
If no port number is provided, the default port for the scheme
is used (389 for ldap://, 636 for ldaps://). For LDAP over IPC,
name is the name of the socket, and no port is required, nor
allowed; note that directory separators must be URL-encoded,
like any other characters that are special to URLs; so the
socket
/usr/local/var/ldapi
must be specified as
ldapi://%2Fusr%2Flocal%2Fvar%2Fldapi
A space separated list of URIs may be provided.
BASE <base>
Specifies the default base DN to use when performing ldap
operations. The base must be specified as a Distinguished Name
in LDAP format.
BINDDN <dn>
Specifies the default bind DN to use when performing ldap
operations. The bind DN must be specified as a Distinguished
Name in LDAP format. This is a user-only option.
DEREF <when>
Specifies how alias dereferencing is done when performing a
search. The <when> can be specified as one of the following
keywords:
never Aliases are never dereferenced. This is the default.
searching
Aliases are dereferenced in subordinates of the base
object, but not in locating the base object of the
search.
finding
Aliases are only dereferenced when locating the base
object of the search.
always Aliases are dereferenced both in searching and in
locating the base object of the search.
HOST <name[:port] ...>
Specifies the name(s) of an LDAP server(s) to which the
LDAP library should connect. Each server's name can be
specified as a domain-style name or an IP address and
optionally followed by a ':' and the port number the ldap
server is listening on. A space separated list of hosts
may be provided. HOST is deprecated in favor of URI.
NETWORK_TIMEOUT <integer>
Specifies the timeout (in seconds) after which the
poll(2)/select(2) following a connect(2) returns in case
of no activity.
PORT <port>
Specifies the default port used when connecting to LDAP
servers(s). The port may be specified as a number. PORT
is deprecated in favor of URI.
REFERRALS <on/true/yes/off/false/no>
Specifies if the client should automatically follow
referrals returned by LDAP servers. The default is on.
Note that the command line tools ldapsearch(1) &co always
override this option.
SIZELIMIT <integer>
Specifies a size limit (number of entries) to use when
performing searches. The number should be a non-negative
integer. SIZELIMIT of zero (0) specifies a request for
unlimited search size. Please note that the server may
still apply any server-side limit on the amount of
entries that can be returned by a search operation.
TIMELIMIT <integer>
Specifies a time limit (in seconds) to use when
performing searches. The number should be a non-negative
integer. TIMELIMIT of zero (0) specifies unlimited
search time to be used. Please note that the server may
still apply any server-side limit on the duration of a
search operation. VERSION {2|3} Specifies what version
of the LDAP protocol should be used.
TIMEOUT <integer>
Specifies a timeout (in seconds) after which calls to
synchronous LDAP APIs will abort if no response is
received. Also used for any ldap_result(3) calls where a
NULL timeout parameter is supplied.
SASL OPTIONS
If OpenLDAP is built with Simple Authentication and Security
Layer support, there are more options you can specify.
SASL_MECH <mechanism>
Specifies the SASL mechanism to use. This is a user-only
option.
SASL_REALM <realm>
Specifies the SASL realm. This is a user-only option.
SASL_AUTHCID <authcid>
Specifies the authentication identity. This is a user-
only option.
SASL_AUTHZID <authcid>
Specifies the proxy authorization identity. This is a
user-only option.
SASL_SECPROPS <properties>
Specifies Cyrus SASL security properties. The
<properties> can be specified as a comma-separated list
of the following:
none (without any other properties) causes the
properties defaults ("noanonymous,noplain") to be
cleared.
noplain
disables mechanisms susceptible to simple passive
attacks.
noactive
disables mechanisms susceptible to active attacks.
nodict disables mechanisms susceptible to passive
dictionary attacks.
noanonymous
disables mechanisms which support anonymous login.
forwardsec
requires forward secrecy between sessions.
passcred
requires mechanisms which pass client credentials
(and allows mechanisms which can pass credentials
to do so).
minssf=<factor>
specifies the minimum acceptable security strength
factor as an integer approximating the effective
key length used for encryption. 0 (zero) implies
no protection, 1 implies integrity protection
only, 56 allows DES or other weak ciphers, 112
allows triple DES and other strong ciphers, 128
allows RC4, Blowfish and other modern strong
ciphers. The default is 0.
maxssf=<factor>
specifies the maximum acceptable security strength
factor as an integer (see minssf description).
The default is INT_MAX.
maxbufsize=<factor>
specifies the maximum security layer receive
buffer size allowed. 0 disables security layers.
The default is 65536.
GSSAPI OPTIONS
If OpenLDAP is built with Generic Security Services Application
Programming Interface support, there are more options you can
specify.
GSSAPI_SIGN <on/true/yes/off/false/no>
Specifies if GSSAPI signing (GSS_C_INTEG_FLAG) should be
used. The default is off.
GSSAPI_ENCRYPT <on/true/yes/off/false/no>
Specifies if GSSAPI encryption (GSS_C_INTEG_FLAG and
GSS_C_CONF_FLAG) should be used. The default is off.
GSSAPI_ALLOW_REMOTE_PRINCIPAL <on/true/yes/off/false/no>
Specifies if GSSAPI based authentication should try to
form the target principal name out of the ldapServiceName
or dnsHostName attribute of the targets RootDSE entry.
The default is off.
TLS OPTIONS
If OpenLDAP is built with Transport Layer Security support,
there are more options you can specify. These options are used
when an ldaps:// URI is selected (by default or otherwise) or
when the application negotiates TLS by issuing the LDAP StartTLS
operation.
TLS_CACERT <filename>
Specifies the file that contains certificates for all of
the Certificate Authorities the client will recognize.
TLS_CACERTDIR <path>
Specifies the path of a directory that contains
Certificate Authority certificates in separate individual
files. The TLS_CACERT is always used before
TLS_CACERTDIR. This parameter is ignored with GnuTLS. On
Debian openldap is linked against GnuTLS.
When using Mozilla NSS, <path> may contain a Mozilla NSS
cert/key database. If <path> contains a Mozilla NSS
cert/key database and CA cert files, OpenLDAP will use
the cert/key database and will ignore the CA cert files.
TLS_CERT <filename>
Specifies the file that contains the client certificate.
This is a user-only option.
When using Mozilla NSS, if using a cert/key database
(specified with TLS_CACERTDIR), TLS_CERT specifies the
name of the certificate to use:
TLS_CERT Certificate for Sam Carter
If using a token other than the internal built in token,
specify the token name first, followed by a colon:
TLS_CERT my hardware device:Certificate for Sam Carter
Use certutil -L to list the certificates by name:
certutil -d /path/to/certdbdir -L
TLS_KEY <filename>
Specifies the file that contains the private key that
matches the certificate stored in the TLS_CERT file.
Currently, the private key must not be protected with a
password, so it is of critical importance that the key
file is protected carefully. This is a user-only option.
When using Mozilla NSS, TLS_KEY specifies the name of a
file that contains the password for the key for the
certificate specified with TLS_CERT. The modutil command
can be used to turn off password protection for the
cert/key database. For example, if TLS_CACERTDIR
specifies /home/scarter/.moznss as the location of the
cert/key database, use modutil to change the password to
the empty string:
modutil -dbdir ~/.moznss -changepw 'NSS Certificate DB'
You must have the old password, if any. Ignore the
WARNING about the running browser. Press 'Enter' for the
new password.
TLS_CIPHER_SUITE <cipher-suite-spec>
Specifies acceptable cipher suite and preference order.
<cipher-suite-spec> should be a cipher specification for
the TLS library in use (OpenSSL, GnuTLS, or Mozilla NSS).
Example:
OpenSSL:
TLS_CIPHER_SUITE HIGH:MEDIUM:+SSLv2
GnuTLS:
TLS_CIPHER_SUITE SECURE256:!AES-128-CBC
To check what ciphers a given spec selects in OpenSSL,
use:
openssl ciphers -v <cipher-suite-spec>
With GnuTLS the available specs can be found in the
manual page of gnutls-cli(1) (see the description of the
option --priority).
In older versions of GnuTLS, where gnutls-cli does not
support the option --priority, you can obtain the --- more
limited --- list of ciphers by calling:
gnutls-cli -l
When using Mozilla NSS, the OpenSSL cipher suite
specifications are used and translated into the format
used internally by Mozilla NSS. There isn't an easy way
to list the cipher suites from the command line. The
authoritative list is in the source code for Mozilla NSS
in the file sslinfo.c in the structure
static const SSLCipherSuiteInfo suiteInfo[]
TLS_PROTOCOL_MIN <major>[.<minor>]
Specifies minimum SSL/TLS protocol version that will be
negotiated. If the server doesn't support at least that
version, the SSL handshake will fail. To require TLS 1.x
or higher, set this option to 3.(x+1), e.g.,
TLS_PROTOCOL_MIN 3.2
would require TLS 1.1. Specifying a minimum that is
higher than that supported by the OpenLDAP implementation
will result in it requiring the highest level that it
does support. This parameter is ignored with GnuTLS.
TLS_RANDFILE <filename>
Specifies the file to obtain random bits from when
/dev/[u]random is not available. Generally set to the
name of the EGD/PRNGD socket. The environment variable
RANDFILE can also be used to specify the filename. This
parameter is ignored with GnuTLS and Mozilla NSS. On
Debian openldap is linked against GnuTLS.
TLS_REQCERT <level>
Specifies what checks to perform on server certificates
in a TLS session, if any. The <level> can be specified as
one of the following keywords:
never The client will not request or check any server
certificate.
allow The server certificate is requested. If no
certificate is provided, the session proceeds
normally. If a bad certificate is provided, it
will be ignored and the session proceeds normally.
try The server certificate is requested. If no
certificate is provided, the session proceeds
normally. If a bad certificate is provided, the
session is immediately terminated.
demand | hard
These keywords are equivalent. The server
certificate is requested. If no certificate is
provided, or a bad certificate is provided, the
session is immediately terminated. This is the
default setting.
TLS_CRLCHECK <level>
Specifies if the Certificate Revocation List (CRL) of the
CA should be used to verify if the server certificates
have not been revoked. This requires TLS_CACERTDIR
parameter to be set. This parameter is ignored with
GnuTLS and Mozilla NSS. On Debian openldap is linked
against GnuTLS. <level> can be specified as one of the
following keywords:
none No CRL checks are performed
peer Check the CRL of the peer certificate
all Check the CRL for a whole certificate chain
TLS_CRLFILE <filename>
Specifies the file containing a Certificate Revocation
List to be used to verify if the server certificates have
not been revoked. This parameter is only supported with
GnuTLS and Mozilla NSS.
ENVIRONMENT VARIABLES
LDAPNOINIT
disable all defaulting
LDAPCONF
path of a configuration file
LDAPRC basename of ldaprc file in $HOME or $CWD
LDAP<option-name>
Set <option-name> as from ldap.conf
FILES
/etc/ldap/ldap.conf
system-wide ldap configuration file
$HOME/ldaprc, $HOME/.ldaprc
user ldap configuration file
$CWD/ldaprc
local ldap configuration file
SEE ALSO
ldap(3), ldap_set_option(3), ldap_result(3), openssl(1), sasl(3)
AUTHOR
Kurt Zeilenga, The OpenLDAP Project
ACKNOWLEDGEMENTS
OpenLDAP Software is developed and maintained by The OpenLDAP Project <http://www.openldap.org/>. OpenLDAP Software is derived from University of Michigan LDAP 3.3 Release.
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