RLOGIND(8c,C) AIX TCP/IP User's Guide RLOGIND(8c,C)
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rlogind
PURPOSE
Provides the server function for the rlogin command.
SYNTAX
/etc/rlogind ---|
DESCRIPTION
The rlogind command is the server for the rlogin program. The server provides
a remote login facility with verification based on privileged port numbers from
trusted hosts.
This command listens for service requests at the port indicated in the login
service specification, see "rc.tcpip, rc.tcpip.local." When a service request
is received, the following protocol is initiated:
1. The server checks the client's source port. If the port is not in the
range 0-1023, the server breaks the connection.
2. The server checks the client's source address and requests the
corresponding host name (refer to gethostbyaddr, in the AIX Operating
System Technical Reference, "hosts" and "named"). If the hostname cannot
be determined, the dot-notation representation of the host address is used.
Once the source port and address have been checked, the rlogind command
allocates a pseudo-terminal (refer to pty in the AIX Operating System Technical
Reference) and manipulates file descriptors so the slave half of the
pseudo-terminal becomes the stdin, stdout, and stderr for a login process. The
login process is an instance of the login program. The login process then
proceeds with the verification process as described in "rshd," but if automatic
authentication fails, it re-prompts the user to log in as one finds on a
standard terminal line.
The parent of the login process manipulates the master side of the
pseduo-terminal, operating as an intermediary between the login process and the
client instance of the rlogin program. In normal operation, the packet
protocol described in pty is invoked to provide Ctrl S/Ctrl Q type facilities
and propagate interrupt signals to the remote programs. The login process
propagates the client terminal's baud rate and terminal type, as found in the
environment variable, TERM. The screen or window size of the terminal is
requested from the client, and window size changes from the client are
propagated to the pseudo-terminal.
Processed October 29, 1990 RLOGIND(8c,C) 1
RLOGIND(8c,C) AIX TCP/IP User's Guide RLOGIND(8c,C)
Note: The verification procedure used here assumes the integrity of each
client machine and the connecting medium. This is insecure, but is useful in
an open environment.
MESSAGES
All diagnostic messages are returned on the connection associated with the
stderr, after which any network connections are closed. An error is indicated
by a leading byte with a value of 1.
RELATED INFORMATION
In this book: "rlogin"
login, refer to AIX Operating System Command Reference
pty, refer to AIX Operating System Technical Reference
syslogd, refer to AIX Operating System Technical Reference
Processed October 29, 1990 RLOGIND(8c,C) 2