It handles plaintext authentication requests on behalf of the SASL library.
Now lets see the manual of saslauthd service.Manual saslauthd:NAME
saslauthd - sasl authentication serverSYNOPSIS
saslauthd -a authmech [-Tvdchlr] [-O option] [-m mux_path] [-n threads] [-s size] [-t timeout]DESCRIPTION
saslauthd is a daemon process that handles plaintext authentication requests on behalf of the SASL library.
The server fulfills two roles: it isolates all code requiring superuser privileges into a single process, and it can
be used to provide proxy authentication services to clients that do not understand SASL based authentication.
saslauthd should be started from the system boot scripts when going to multi-user mode. When running against a protected
authentication database (e.g. the shadow mechanism), it must be run as the superuser.
Options named by lower-case letters configure the server itself. Upper-case options control the behavior of specific
authentication mechanisms; their applicability to a particular authentication mechanism is described in the
AUTHENTICATION MECHANISMS section.
Use authmech as the authentication mechanism. (See the AUTHENTICATION MECHANISMS section below.) This parameter
A mechanism specific option (e.g. rimap hostname or config file path)
The remote host to be contacted by the rimap authentication mechanism. (Depricated, use -O instead)
Use path as the pathname to the named socket to listen on for connection requests. This must be an absolute
pathname, and MUST NOT include the trailing "/mux". Note that the default for this value is
"/var/state/saslauthd" (or what was specified at compile time) and that this directory must exist for saslauthd
Use threads processes for responding to authentication queries. (default: 5) A value of zero will indicate
that saslauthd should fork an individual process for each connection. This can solve leaks that occur in
Use size as the table size of the hash table (in kilobytes)
Use timeout as the expiration time of the authentication cache (in seconds)
-T Honour time-of-day login restrictions.
-h Show usage information
-c Enable cacheing of authentication credentials
-l Disable the use of a lock file for controlling access to accept().
-r Combine the realm with the login (with an '@' sign in between). e.g. login: "foo" realm: "bar" will get
passed as login: "foo@bar". Note that the realm will still be passed, which may lead to unexpected behavior.
-v Print the version number and available authentication mechanisms on standard error, then exit.
-d Debugging mode.
saslauthd logs it's activities via syslogd using the LOG_AUTH facility.AUTHENTICATION MECHANISMS
saslauthd supports one or more "authentication mechanisms", dependent upon the facilities provided by the underlying
operating system. The mechanism is selected by the -aho flag from the following list of choices:
Authenticate using the DCE authentication environment.
getpwent (All platforms)
Authenticate using the getpwent() library function. Typically this authenticates against the local password
file. See your systems getpwent(3) man page for details.
kerberos4 (All platforms)
Authenticate against the local Kerberos 4 realm. (See the NOTES section for caveats about this driver.)
kerberos5 (All platforms)
Authenticate against the local Kerberos 5 realm.
pam (Linux, Solaris)
Authenticate using Pluggable Authentication Modules (PAM).
rimap (All platforms)
Forward authentication requests to a remote IMAP server. This driver connects to a remote IMAP server,
specified using the -O flag, and attempts to login (via an IMAP 'LOGIN' command) using the credentials
supplied to the local server. If the remote authentication succeeds the local connection is also considered
to be authenticated. The remote connection is closed as soon as the tagged response from the 'LOGIN'
command is received from the remote server.
The option parameter to the -O flag describes the remote server to forward authentication requests to.
hostname can be a hostname (imap.example.com) or a dotted-quad IP address (192.168.0.1). The latter is
useful if the remote server is multi-homed and has network interfaces that are unreachable from the local
IMAP server. The remote host is contacted on the 'imap' service port. A non-default port can be specified
by appending a slash and the port name or number to the hostname argument.
The -O flag and argument are mandatory when using the rimap mechanism.
shadow (AIX, Irix, Linux, Solaris)
Authenticate against the local "shadow password file". The exact mechanism is system dependent.
saslauthd currently understands the getspnam() and getuserpw() library routines. Some systems honour the
sasldb (All platforms)
Authenticate against the SASL authentication database. Note that this is probabally not what you want to
be using, and is even disabled at compile-time by default. If you want to use sasldb with the SASL
library, you probably want to use the pwcheck_method of "auxprop" along with the sasldb auxprop plugin
ldap (All platforms that support OpenLDAP 2.0 or higher)
Authenticate against an ldap server. The ldap configuration parameters are read from
/usr/local/etc/saslauthd.conf. The location of this file can be changed with the -O parameter. See the
LDAP_SASLAUTHD file included with the distribution for the list of available parameters.
sia (Digital UNIX)
Authenticate using the Digital UNIX Security Integration Architecture (a.k.a. "enhanced security").NOTES
The kerberos4 authentication driver consumes considerable resources. To perform an authentication it must obtain a
ticket granting ticket from the TGT server on every authentication request. The Kerberos library routines that obtain
the TGT also create a local ticket file, on the reasonable assumption that you will want to save the TGT for use by
other Kerberos applications. These ticket files are unusable by saslauthd , however there is no way not to create
them. The overhead of creating and removing these ticket files can cause serious performance degradation on busy
servers. (Kerberos was never intended to be used in this manner, anyway.)FILES
/var/run/saslauthd/mux The default communications socket.
The default configuration file for ldap support.SEE ALSO
passwd(1), getpwent(3), getspnam(3), getuserpw(3), sasl_checkpass(3) sia_authenticate_user(3),