usr/src/sys/net/if_llc.h

/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)if_llc.h    7.2 (Berkeley) %G%
 */

/*
 * IEEE 802.2 Link Level Control headers, for use in conjunction with
 * 802.{3,4,5} media access control methods.
 *
 * Headers here do not use bit fields due to shortcommings in many
 * compilers.
 */

struct llc {
        u_char  llc_dsap;
        u_char  llc_ssap;
        union {
            struct {
                u_char control;
                u_char format_id;
                u_char class;
                u_char window_x2;
            } type_u;
            struct {
                u_char num_snd_x2;
                u_char num_rcv_x2;
            } type_i;
            struct {
                u_char control;
                u_char num_rcv_x2;
            } type_s;
            struct {
                u_char control;
                u_char org_code[3];
                u_short ether_type;
            } type_snap;
        } llc_un;
};
#define llc_control llc_un.type_u.control
#define llc_fid llc_un.type_u.format_id
#define llc_class llc_un.type_u.class
#define llc_window llc_un.type_u.window_x2

#define LLC_UI          0x3
#define LLC_UI_P        0x13
#define LLC_XID         0xaf
#define LLC_XID_P       0xbf
#define LLC_TEST        0xe3
#define LLC_TEST_P      0xf3

#define LLC_ISO_LSAP    0xfe
#define LLC_SNAP_LSAP   0xaa