rlogind(1M) rlogind(1M)NAME rlogind - server for remote logins SYNOPSIS in.rlogind host.port ARGUMENTS host.port Specifies the client's host address (in hex) and port number (in decimal). DESCRIPTION rlogind is the server for the rlogin(1N) program. The server provides a remote login facility with authentication based on privileged port numbers. The rlogind command listens for service requests at the port indicated in the login service specification; see services(4N). When rlogind receives a service request, it initiates the following protocol. 1. The server checks the client's source port. If the port is not in the range 0 to 1023, the server aborts the connection. The client's host address (in hex) and port number (in decimal) are the arguments passed to rlogind. 2. The server checks the client's source address. If the address is associated with a host that has no corresponding entry in the host name database (see hosts(4N)), the server aborts the connection. Once it has checked the source port and address, rlogind allocates a pseudo terminal (see pty(7)), and manipulates file descriptors so that 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(1) program, invoked with the -r option. The login process then proceeds with authentication, as described in remshd(1M). If automatic authentication fails, it reprompts the user to login, as on a standard terminal line. The parent of the login process manipulates the master side of the pseudo 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(7) is invoked to provide CONTROL-S/CONTROL-D 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; (see environ(5)). January 1992 1
rlogind(1M) rlogind(1M)STATUS MESSAGES AND VALUES The rlogind command returns all diagnostic messages on the connection associated with the stderr, after which it closes any network connections. It indicates an error by a leading byte with a value of 1. Hostname for your address unknown. There is no entry in the host name database for the client's machine. Try again. A fork by the server failed. /bin/sh: ... Could not start the user's login shell. LIMITATIONS The authentication procedure used here assumes the integrity of each client machine and the connecting medium. This is insecure, but is useful in an ``open'' environment. FILES /etc/in.rlogind Executable file 2 January 1992