Require compare (not read) access to entry attr for compare ops

doc/man/man5/slapd-sock.5

@@ -186,11 +186,8 @@ to the underlying program.
 The
 .B compare
 operation requires 
-.B read (=r)
-access (FIXME: wouldn't 
 .B compare (=c)
-be a more appropriate choice?)
-to the 
+access to the 
 .B entry
 pseudo-attribute
 of the object whose value is being asserted;

servers/slapd/back-sock/compare.c

@@ -48,7 +48,7 @@ sock_back_compare(
 	e.e_private = NULL;
 
 	if ( ! access_allowed( op, &e,
-		entry, NULL, ACL_READ, NULL ) )
+		entry, NULL, ACL_COMPARE, NULL ) )
 	{
 		send_ldap_error( op, rs, LDAP_INSUFFICIENT_ACCESS, NULL );
 		return -1;