pw_auth3pwauthadministrator defined password authentication routinesSYNTAX#include <pwauth.h>int pw_auth (char*command,char*user,intreason,char*input);DESCRIPTIONpw_auth
invokes the administrator defined functions for a given user.
command is the name of the
authentication program. It is retrieved from the user's password file
information. The string contains one or more executable file names,
delimited by semi-colons. Each program will be executed in the order
given. The command line arguments are given for each of the reasons
listed below.
user is the name of the user to be
authenticated, as given in the /etc/passwd file.
User entries are indexed by username. This allows non-unique user IDs
to be present and for each different username associated with that
user ID to have a different authentication program and information.
Each of the permissible authentication reasons is handled in a
potentially differenent manner. Unless otherwise mentioned, the
standard file descriptors 0, 1, and 2 are available for communicating
with the user. The real user ID may be used to determine the identity
of the user making the authentication request. reason is one of
PW_SUPerform authentication for the current real user ID
attempting to switch real user ID to the named user. The
authentication program will be invoked with a
option, followed by the username.
PW_LOGINPerform authentication for the named user creating a new
login session. The authentication program will be invoked with a
option, followed by the username.
PW_ADDCreate a new entry for the named user. This allows an
authentication program to initialize storage for a new user. The
authentication program will be invoked with a
option, followed by the username.
PW_CHANGEAlter an existing entry for the named user. This allows an
authentication program to alter the authentication information
for an existing user. The authentication program will be invoked
with a option, followed by the username.
PW_DELETEDelete authentication information for the named user. This
allows an authentication program to reclaim storage for a user
which is no longer authenticated using the authentication
program. The authentication program will be invoked with a
option, followed by the username.
PW_TELNETAuthenticate a user who is connecting to the system using
the telnet command. The
authentication program will be invoked with a
option, followed by the username.
PW_RLOGIN
Authenticate a user who is connecting to the system using the
rlogin command. The
authentication program will be invoked with a
option, followed by the username.
PW_FTP
Authenticate a user who is connecting to the system using the
ftp command. The authentication
program will be invoked with a option,
followed by the username. The standard file descriptors are not
available for communicating with the user. The standard input
file descriptor will be connected to the parent process, while
the other two output file descriptors will be connected to
/dev/null. The pw_auth function will pipe a single line of
data to the authentication program using file descriptor 0.
PW_REXEC
Authenticate a user who is connecting to the system using the
rexec command. The authentication
program will be invoked with a option,
followed by the username. The standard file descriptors are not
available for communicating with the remote user. The standard
input file descriptor will be connected to the parent process,
while the other two output file descriptors will be connected to
/dev/null. The pw_auth function will pipe a single line of
data to the authentication program using file descriptor 0.
The last argument is the authentication data which is used by the
PW_FTP and PW_REXEC reasons. It is treated as a single line
of text which is piped to the authentication program. When the reason
is PW_CHANGE, the value of input is the value of previous user name if the
user name is being changed.
CAVEATSThis function does not create the actual session. It only
indicates if the user should be allowed to create the session.
The network options are untested at this time.DIAGNOSTICS
The pw_auth function returns 0 if the
authentication program exited with a 0 exit code, and a non-zero value
otherwise.
SEE ALSOlogin1,
passwd1,
su1,
useradd8,
userdel8,
usermod8AUTHORJulianne Frances Haugh (jockgrrl@ix.netcom.com)