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Diffstat (limited to 'epan/xdlc.h')
| -rw-r--r-- | epan/xdlc.h | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/epan/xdlc.h b/epan/xdlc.h new file mode 100644 index 0000000000..fc924ef6ee --- /dev/null +++ b/epan/xdlc.h @@ -0,0 +1,140 @@ +/* xdlc.h + * Define *DLC frame types, and routine to dissect the control field of + * a *DLC frame. + * + * $Id$ + * + * Ethereal - Network traffic analyzer + * By Gerald Combs <gerald@ethereal.com> + * Copyright 1998 Gerald Combs + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#ifndef __XDLC_H__ +#define __XDLC_H__ + +/* + * 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 guchar *pd, int offset, int extended); + +extern 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, int is_response, + int is_extended, int append_info); + +#endif |