HOSTS.EQUIV(4-SysV) RISC/os Reference Manual  HOSTS.EQUIV(4-SysV)



NAME
     hosts.equiv - list of trusted hosts

DESCRIPTION
     hosts.equiv resides in directory /etc and contains a list of
     trusted hosts.  When an rlogin(1) or rsh(1C) request from
     such a host is made, and the initiator of the request is in
     /etc/passwd, then no further validity checking is done:
     rlogin does not prompt for a password, and rsh completes
     successfully.  Thus, a remote user is ``equivalenced'' to a
     local user with the same user name when the remote user is
     in hosts.equiv.

     The format of hosts.equiv is a list of names, as in this
     example:

           host1
           host2
           +@group1
           -@group2

     A line consisting of a simple host name means that anyone
     logging in from that host is trusted.  A line consisting of
     +@group means that all hosts in that network group are
     trusted.  A line consisting of -@group means that hosts in
     that group are not trusted.  Programs scan hosts.equiv
     linearly, and stop at the first hit (either positive for
     hostname and +@ entries, or negative for -@ entries).  A
     line consisting of a single + means that everyone is
     trusted.

     The .rhosts file has the same format as hosts.equiv. When
     user XXX executes rlogin or rsh, the .rhosts file from XXX's
     home directory is conceptually concatenated onto the end of
     hosts.equiv for permission checking.  However, -@ entries
     are not sticky.  If a user is excluded by a minus entry from
     hosts.equiv but included in .rhosts, then that user is con-
     sidered trusted.  In the special case when the user is root,
     then only the /.rhosts file is checked.

     It is also possible to have two entries (separated by a sin-
     gle space) on a line of these files.  In this case, if the
     remote host is equivalenced by the first entry, then the
     user named by the second entry is allowed to log in as any-
     one, that is, specify any name to the -l flag (provided that
     name is in the /etc/passwd file, of course).  Thus the entry

           sundown john

     in /etc/hosts.equiv allows john to log in from sundown as
     anyone.  The usual usage would be to put this entry in the
     .rhosts file in the home directory for bill. Then john may



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HOSTS.EQUIV(4-SysV) RISC/os Reference Manual  HOSTS.EQUIV(4-SysV)



     log in as bill when coming from sundown.  The second entry
     may be a netgroup, thus

           +@group1 +@group2

     allows any user in group2 coming from a host in group1 to
     log in as anyone.

FILES
     /etc/hosts.equiv
     ~/.rhosts

WARNING
     The references to network groups (+@ and -@ entries) in
     hosts.equiv and .rhosts are only supported when the netgroup
     file is supplied by the Network Information Service.

SEE ALSO
     netgroup(4), rhosts(4).

ORIGIN
     4.3 BSD

































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