REXECD(8N)              COMMAND REFERENCE              REXECD(8N)



NAME
     rexecd - remote execution server

SYNOPSIS
     /etc/rexecd

DESCRIPTION
     Rexecd is the server for the rexec(3n) routine.  The server
     provides remote execution facilities with authentication
     based on user names and encrypted passwords.

     Rexecd is started by inetd(8n) when a service requests at
     the port indicated in the ``exec'' service specification;
     see services(5n).  When a service request is received the
     following protocol is initiated:

          1.The server reads characters from the socket up to a
            null (`\0') byte.  The resultant string is
            interpreted as an ASCII number, base 10.

          2.If the number received in step 1 is non-zero, it is
            interpreted as the port number of a secondary stream
            to be used for the stderr.  A second connection is
            then created to the specified port on the client's
            machine.

          3.A null terminated user name of at most 16 characters
            is retrieved on the initial socket.

          4.A null terminated, encrypted, password of at most 16
            characters is retrieved on the initial socket.

          5.A null terminated command to be passed to a shell is
            retrieved on the initial socket.  The length of the
            command is limited by the upper bound on the size of
            the system's argument list.

          6.Rexecd then validates the user as is done at login
            time and, if the authentication was successful,
            changes to the user's home directory, and establishes
            the user and group protections of the user.  If any
            of these steps fail the connection is aborted with a
            diagnostic message returned.

          7.A null byte is returned on the connection associated
            with the stderr and the command line is passed to the
            normal login shell of the user.  The shell inherits
            the network connections established by rexecd.

DIAGNOSTICS
     All diagnostic messages are returned on the connection
     associated with the stderr, after which any network



Printed 4/6/89                                                  1

REXECD(8N)              COMMAND REFERENCE              REXECD(8N)



     connections are closed.  An error is indicated by a leading
     byte with a value of 1 (0 is returned in step 7 above upon
     successful completion of all the steps prior to the command
     execution).

     username too long
                    The name is longer than 16 characters.

     password too long
                    The password is longer than 16 characters.

     command too long
                    The command line passed exceeds the size of
                    the argument list (as configured into the
                    system).

     Login incorrect.
                    No password file entry for the user name
                    existed or the wrong password was supplied.

     No remote directory.
                    The chdir command to the home directory
                    failed.

     Try again.     A fork by the server failed.

     /bin/sh: ...   The user's login shell could not be started.

RETURN VALUE
     [0]            Rexecd is running.

     [1]            Rexecd is not running.

     [USAGE]        Incorrect command line syntax. Execution
                    terminated.

     [P_ERR]        A system error occurred. Execution
                    terminated.  See intro(2) for more
                    information on system errors.

     [NP_WARN]      An error warranting a warning message
                    occurred. Execution continues.

SEE ALSO
     rexec(3n), and inetd(8n).










Printed 4/6/89                                                  2

%%index%%
na:312,84;
sy:396,217;
de:613,2475;
di:3088,299;3771,1133;
rv:4904,704;
se:5608,145;
%%index%%000000000118