NAME
identd — TCP/IP IDENT protocol server
SYNOPSIS
/usr/lbin/identd
[-i|
-w|-b]
[-t
seconds]
[-u
uid]
[-g
gid]
[-p
port]
[-a
address]
[-c
charset]
[-n]
[-o]
[-e]
[-l]
[-V]
[-m]
[-N]
[-d]
DESCRIPTION
identd
is a server which implements the
TCP/IP proposed standard IDENT
user identification protocol as specified in the
RFC 1413 document.
identd
operates by looking up specific
TCP/IP
connections and returning the user name of the
process owning the connection.
Arguments
- -i
The
-i
flag, which is the default mode, should be used when starting the
daemon from
inetd
with the "nowait" option in the
/etc/inetd.conf
file. Use of this mode will make
inetd
start one
identd
daemon for each connection request.
- -w
The
-w
flag should be used when starting the daemon from
inetd
with the "wait" option in the
/etc/inetd.conf
file.
The
identd
daemon will run either forever,
until a timeout, as specified by the
-t
flag, occurs.
- -b
The
-b
flag can be used to make the daemon run in standalone mode without
the assistance from
inetd.
This mode is the least preferred mode, and not supported by HP, since
a bug or any other fatal condition in the server will make it terminate
and it will then have to be restarted manually.
- -tseconds
The
-tseconds
option is used to specify the timeout limit. This is the number
of seconds a server started with the
-w
flag will wait for new connections before terminating. The server is
automatically restarted by
inetd
whenever a new connection is requested
if it has terminated. A suitable value for this is 120 (2 minutes), if
used. It defaults to no timeout.
That is, it will wait forever, or until a fatal condition occurs in
the server.
- -uuid
The
-uuid
option is used to specify a user id number which the
ident
server should
switch to after binding itself to the
TCP/IP
port if using the
-b
mode of operation.
- -ggid
The
-ggid
option is used to specify a group id number which the
ident
server should
switch to after binding itself to the
TCP/IP
port if using the
-b
mode of operation.
- -pport
The
-pport
option is used to specify an alternative port number to bind to if using
the
-b
mode of operation. It can be specified by name or by number. Defaults to the
IDENT
port (113).
- -aaddress
The
-aaddress
option is used to specify the local address to bind the socket to if using
the
-b
mode of operation.
Can only be specified by the IP address and not by the domain name.
The default value in IPv4 is
INADDR_ANY,
and in IPv6 it is
in6addr_any,
which normally represents all the local addresses.
- -V
The
-V
flag makes
identd
display the version number and the exit.
- -l
The
-l
flag tells
identd
to use the System logging daemon
syslogd
for logging purposes.
- -o
The
-o
flag tells
identd
to not reveal the operating system type it is run on and to instead
always return "OTHER".
- -e
The
-e
flag tells
identd
to always return
UNKNOWN-ERROR
instead of the
NO-USER
or
INVALID-PORT
errors.
- -ccharset
The
-ccharset
flags tells
identd
to add the optional (according to the IDENT protocol) character set
designator to the reply generated.
<charset>
should be a valid character
set as described in the MIME RFC in upper case characters.
- -n
The
-n
flags tells
identd
to always return user numbers instead of user names if you wish to
keep the user names a secret.
- -N
The
-N
flag makes
identd
check for a file
.noident
in each home directory for a user which the
daemon is about to return the user name for. It that file exists then the
daemon will give the error
HIDDEN-USER
instead of the normal
USERID
response.
- -m
The
-m
flag makes
identd
use a mode of operation that will allow multiple requests to be
processed per session. Each request is specified one per line and
the responses will be returned one per line. The connection will not
be closed until the connecting part closes its end of the line.
Please note that this mode violates the protocol specification as it currently stands.
- -d
The
-d
flag enables some debugging code that normally should
NOT
be enabled since that breaks the protocol and may reveal information
that should not be available to outsiders.
INSTALLATION
identd
is invoked either by the internet server (see
inetd(1M))
for requests to connect to the
IDENT
port as indicated by the
/etc/services
file (see
services(4))
when using the
-w
or
-i
modes of operation or started manually by using the
-b
mode of operation.
WARNINGS
The options
-w
and
-t
are currently not supported on HP-UX.
EXAMPLES
Since the server is located in
/usr/lbin/identd,
you can put either:
ident stream tcp6 wait bin /usr/lbin/identd identd -w -t120
or:
ident stream tcp6 nowait bin /usr/lbin/identd identd -i
into the
/etc/inetd.conf
file.
To start it using the unsupported
-b
mode of operation, you can put a line like this into the
/sbin/init.d/sendmail
file under the 'start' section:
/usr/lbin/identd -b -u2 -g2
This will cause
identd
to be started as daemon whenever
sendmail
is running. It will run in the background as user 2, group 2 (user
bin,
group
bin).