D_PASSWD(5) File Formats and Configurations D_PASSWD(5)

NAME

d_passwd - dial-up password file

SYNOPSIS

/etc/d_passwd

DESCRIPTION

A dial-up password is an additional password required of users who
access the computer through a modem or dial-up port. The correct
password must be entered before the user is granted access to the
computer.


d_passwd is an ASCII file which contains a list of executable
programs (typically shells) that require a dial-up password and the
associated encrypted passwords. When a user attempts to log in on any
of the ports listed in the dialups file (see dialups(5)), the login
program looks at the user's login entry stored in the passwd file
(see passwd(5)), and compares the login shell field to the entries in
d_passwd. These entries determine whether the user will be required
to supply a dial-up password.


Each entry in d_passwd is a single line of the form:

login-shell:password:


where

login-shell
The name of the login program that will require an
additional dial-up password.


password
An encrypted password. Users accessing the computer
through a dial-up port or modem using login-shell
will be required to enter this password before gaining
access to the computer.


d_passwd should be owned by the root user and the root group. The
file should have read and write permissions for the owner (root)
only.


If the user's login program in the passwd file is not found in
d_passwd or if the login shell field in passwd is empty, the user
must supply the default password. The default password is the entry
for /usr/bin/sh. If d_passwd has no entry for /usr/bin/sh, then those
users whose login shell field in passwd is empty or does not match
any entry in d_passwd will not be prompted for a dial-up password.


Dial-up logins are disabled if d_passwd has only the following entry:

/usr/bin/sh:*:

EXAMPLES

Example 1: Sample d_passwd file.

Here is a sample d_passwd file:


/usr/lib/uucp/uucico:q.mJzTnu8icF0:
/usr/bin/csh:6k/7KCFRPNVXg:
/usr/bin/ksh:9df/FDf.4jkRt:
/usr/bin/sh:41FuGVzGcDJlw:

Generating An Encrypted Password

The passwd (see passwd(1)) utility can be used to generate the
encrypted password for each login program. passwd generates encrypted
passwords for users and places the password in the shadow (see
shadow(5)) file. Passwords for the d_passwd file will need to be
generated by first adding a temporary user id using useradd (see
useradd(8)), and then using passwd(1) to generate the desired
password in the shadow file. Once the encrypted version of the
password has been created, it can be copied to the d_passwd file.


For example:

1. Type useradd tempuser and press Return. This creates a
user named tempuser.

2. Type passwd tempuser and press Return. This creates an
encrypted password for tempuser and places it in the
shadow file.

3. Find the entry for tempuser in the shadow file and copy
the encrypted password to the desired entry in the
d_passwd file.

4. Type userdel tempuser and press Return to delete tempuser.


These steps must be executed as the root user.

FILES

/etc/d_passwd
dial-up password file


/etc/dialups
list of dial-up ports requiring dial-up passwords


/etc/passwd
password file


/etc/shadow
shadow password file

SEE ALSO

passwd(1), dialups(5), passwd(5), shadow(5), useradd(8)

WARNINGS

When creating a new dial-up password, be sure to remain logged in on
at least one terminal while testing the new password. This ensures
that there is an available terminal from which you can correct any
mistakes that were made when the new password was added.

September 2, 2004 D_PASSWD(5)