wireshark/epan/xdlc.h

133 lines
4.5 KiB
C

/* xdlc.h
* Define *DLC frame types, and routine to dissect the control field of
* a *DLC frame.
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#ifndef __XDLC_H__
#define __XDLC_H__
#include "ws_symbol_export.h"
/** @file
* Define *DLC frame types, and routine to dissect the control field of
* a *DLC frame.
*/
/*
* Low-order bits of first (extended) or only (basic) octet of control
* field, specifying the frame type.
*/
#define XDLC_I_MASK 0x01 /**< Mask to test for I or not I */
#define XDLC_I 0x00 /**< Information frames */
#define XDLC_S_U_MASK 0x03 /**< Mask to test for S or U */
#define XDLC_S 0x01 /**< Supervisory frames */
#define XDLC_U 0x03 /**< Unnumbered frames */
/*
* N(S) and N(R) fields, in basic and extended operation.
*/
#define XDLC_N_R_MASK 0xE0 /**< basic */
#define XDLC_N_R_SHIFT 5
#define XDLC_N_R_EXT_MASK 0xFE00 /**< extended */
#define XDLC_N_R_EXT_SHIFT 9
#define XDLC_N_S_MASK 0x0E /**< basic */
#define XDLC_N_S_SHIFT 1
#define XDLC_N_S_EXT_MASK 0x00FE /**< extended */
#define XDLC_N_S_EXT_SHIFT 1
/*
* Poll/Final bit, in basic and extended operation.
*/
#define XDLC_P_F 0x10 /**< basic */
#define XDLC_P_F_EXT 0x0100 /**< extended */
/*
* S-format frame types.
*/
#define XDLC_S_FTYPE_MASK 0x0C
#define XDLC_RR 0x00 /**< Receiver ready */
#define XDLC_RNR 0x04 /**< Receiver not ready */
#define XDLC_REJ 0x08 /**< Reject */
#define XDLC_SREJ 0x0C /**< Selective reject */
/*
* U-format modifiers.
*/
#define XDLC_U_MODIFIER_MASK 0xEC
#define XDLC_UI 0x00 /**< Unnumbered Information */
#define XDLC_UP 0x20 /**< Unnumbered Poll */
#define XDLC_DISC 0x40 /**< Disconnect (command) */
#define XDLC_RD 0x40 /**< Request Disconnect (response) */
#define XDLC_UA 0x60 /**< Unnumbered Acknowledge */
#define XDLC_SNRM 0x80 /**< Set Normal Response Mode */
#define XDLC_TEST 0xE0 /**< Test */
#define XDLC_SIM 0x04 /**< Set Initialization Mode (command) */
#define XDLC_RIM 0x04 /**< Request Initialization Mode (response) */
#define XDLC_FRMR 0x84 /**< Frame reject */
#define XDLC_CFGR 0xC4 /**< Configure */
#define XDLC_SARM 0x0C /**< Set Asynchronous Response Mode (command) */
#define XDLC_DM 0x0C /**< Disconnected mode (response) */
#define XDLC_SABM 0x2C /**< Set Asynchronous Balanced Mode */
#define XDLC_SARME 0x4C /**< Set Asynchronous Response Mode Extended */
#define XDLC_SABME 0x6C /**< Set Asynchronous Balanced Mode Extended */
#define XDLC_RESET 0x8C /**< Reset */
#define XDLC_XID 0xAC /**< Exchange identification */
#define XDLC_SNRME 0xCC /**< Set Normal Response Mode Extended */
#define XDLC_BCN 0xEC /**< Beacon */
/**
* This macro takes the control field of an xDLC frame, as returned by
* "get_xdlc_control()" or "dissect_xdlc_control()", and evaluates to
* TRUE if the frame is an "information" frame and FALSE if it isn't.
* Note that frames other than information frames can have data in them,
* e.g. TEST frames.
*/
#define XDLC_IS_INFORMATION(control) \
(((control) & XDLC_I_MASK) == XDLC_I || (control) == (XDLC_UI|XDLC_U))
/**
* This macro takes the control field of an xDLC frame, and a flag saying
* whether we're doing basic or extended operation, and evaluates to
* the length of that field (if it's an Unnumbered frame, or we're not
* in extended mode, it's 1 byte long, otherwise it's 2 bytes long).
*/
#define XDLC_CONTROL_LEN(control, is_extended) \
((((control) & XDLC_S_U_MASK) == XDLC_U || !(is_extended)) ? 1 : 2)
/**
* Structure containing pointers to hf_ values for various subfields of
* the control field.
*/
typedef struct {
int *hf_xdlc_n_r;
int *hf_xdlc_n_s;
int *hf_xdlc_p;
int *hf_xdlc_f;
int *hf_xdlc_s_ftype;
int *hf_xdlc_u_modifier_cmd;
int *hf_xdlc_u_modifier_resp;
int *hf_xdlc_ftype_i;
int *hf_xdlc_ftype_s_u;
} xdlc_cf_items;
extern const value_string ftype_vals[];
extern const value_string stype_vals[];
extern const value_string modifier_vals_cmd[];
extern const value_string modifier_vals_resp[];
extern int get_xdlc_control(const guint8 *pd, int offset, gboolean is_extended);
WS_DLL_PUBLIC int dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo,
proto_tree *xdlc_tree, int hf_xdlc_control, gint ett_xdlc_control,
const xdlc_cf_items *cf_items_nonext, const xdlc_cf_items *cf_items_ext,
const value_string *u_modifier_short_vals_cmd,
const value_string *u_modifier_short_vals_resp, gboolean is_response,
gboolean is_extended, gboolean append_info);
#endif