pwdauthd - server for authenticating passwords
This program is available with the Security software installation
option. Refer to for information on how to install optional software.
pwdauthd is a server that determines authentication for users and
groups. It handles authentication requests from pwdauth(3) and
grpauth(). Communication to and from pwdauthd is by means of RPC
calls. The server is passed a filename and a password. It returns an
integer value that specifies whether the password is valid. The possi-
ble return values are PWA_VALID if the name is valid, PWA_INVALID if
the name is invalid, and PWA_UNKNOWN if validity cannot be determined
because no adjunct files are present.
If pwdauthd is serving pwdauth, it determines whether the
passwd.adjunct file exists. If not, it returns PWA_UNKNOWN. In this
case, pwdauth knows to check the /etc/passwd file. Otherwise, the
server calls getpwanam() (see getpwaent(3)) to get the entry for file-
name in either the local or the Network Information Service (NIS) file
for passwd.adjunct. If the encrypted password guess matches the
encrypted password from the file, pwdauthd returns PWA_VALID. If the
passwords do not match, it returns PWA_INVALID.
If pwdauthd is serving grpauth(), it determines whether the
group.adjunct file exists. If not, it returns PWA_UNKNOWN. In this
case, grpauth() knows to check the /etc/group file. Otherwise, the
server calls getgranam() (see getgraent(3)) to get the entry for file-
name in either the local or the NIS file for group.adjunct. If the
encrypted password guess matches the encrypted password from the file,
pwdauthd returns PWA_VALID. If the passwords do not match, it returns
getgraent(3), getpwaent(3), pwdauth(3)
The Network Information Service (NIS) was formerly known as Sun Yellow
Pages (YP). The functionality of the two remains the same; only the
name has changed.
21 December 1987 PWDAUTHD(8C)