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(1) request from such a host is made, and the initiator of the request is in /etc/passwd, then no further validity checking is done. That is, rlogin does not prompt for a password, and rsh completes successfully.  So a remote user is “equivalenced” to a local user with the same user ID 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 members of that network group are trusted.  A line consisting of −@group means that members of 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 considered 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 single space) on a line of these files.  In this case, if the remote user is equivalenced by the first entry, then that user is allowed to log in as any member of the second entry.  Thus

 sundown john

allows anyone from sundown to log in as john, and

 +@group1 +@group2

allows any member of netgroup1 to log in as a member of netgroup2.

FILES

/etc/hosts.equiv

SEE ALSO

rlogin(1), rsh(1), netgroup(5)

Sun Release 2.0  —  Last change: 1 February 1985