d_passwd(4)
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 execut-
able 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(4)), the login program looks at
the user's login entry stored in the passwd file (see
passwd(4)), 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
A 13-character 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 follow-
ing 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 gen-
erates encrypted passwords for users and places the password
in the shadow (see shadow(4)) file. Passwords for the
d_passwd file will need to be generated by first adding a
temporary user id using useradd (see useradd(1M)), and
then using passwd(1) to generate the desired password in
the shadow file. Once the encrypted version of the pass-
word 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), useradd(1M), dialups(4), passwd(4), shadow(4)
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.
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