diff options
Diffstat (limited to 'xdlc.c')
| -rw-r--r-- | xdlc.c | 302 |
1 files changed, 126 insertions, 176 deletions
@@ -2,7 +2,7 @@ * Routines for use by various SDLC-derived protocols, such as HDLC * and its derivatives LAPB, IEEE 802.2 LLC, etc.. * - * $Id: xdlc.c,v 1.21 2003/09/02 19:18:52 guy Exp $ + * $Id: xdlc.c,v 1.22 2004/01/03 03:49:23 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs <gerald@ethereal.com> @@ -34,39 +34,19 @@ #include <epan/packet.h> #include "xdlc.h" -/* - * 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 */ +const value_string ftype_vals[] = { + { XDLC_I, "Information frame" }, + { XDLC_S, "Supervisory frame" }, + { XDLC_U, "Unnumbered frame" }, + { 0, NULL } +}; -static const value_string stype_vals[] = { - { XDLC_RR, "Receiver ready" }, - { XDLC_RNR, "Receiver not ready" }, - { XDLC_REJ, "Reject" }, - { XDLC_SREJ, "Selective reject" }, - { 0, NULL } +const value_string stype_vals[] = { + { XDLC_RR>>2, "Receiver ready" }, + { XDLC_RNR>>2, "Receiver not ready" }, + { XDLC_REJ>>2, "Reject" }, + { XDLC_SREJ>>2, "Selective reject" }, + { 0, NULL } }; static const value_string modifier_short_vals_cmd[] = { @@ -91,25 +71,25 @@ static const value_string modifier_short_vals_cmd[] = { { 0, NULL } }; -static const value_string modifier_vals_cmd[] = { - { XDLC_UI, "Unnumbered Information" }, - { XDLC_UP, "Unnumbered Poll" }, - { XDLC_DISC, "Disconnect" }, - { XDLC_UA, "Unnumbered Acknowledge" }, - { XDLC_SNRM, "Set Normal Response Mode" }, - { XDLC_TEST, "Test" }, - { XDLC_SIM, "Set Initialization Mode" }, - { XDLC_FRMR, "Frame reject" }, - { XDLC_CFGR, "Configure" }, - { XDLC_SARM, "Set Asynchronous Response Mode" }, - { XDLC_SABM, "Set Asynchronous Balanced Mode" }, - { XDLC_SARME, "Set Asynchronous Response Mode Extended" }, - { XDLC_SABME, "Set Asynchronous Balanced Mode Extended" }, - { XDLC_RESET, "Reset" }, - { XDLC_XID, "Exchange identification" }, - { XDLC_SNRME, "Set Normal Response Mode Extended" }, - { XDLC_BCN, "Beacon" }, - { 0, NULL } +const value_string modifier_vals_cmd[] = { + { XDLC_UI>>2, "Unnumbered Information" }, + { XDLC_UP>>2, "Unnumbered Poll" }, + { XDLC_DISC>>2, "Disconnect" }, + { XDLC_UA>>2, "Unnumbered Acknowledge" }, + { XDLC_SNRM>>2, "Set Normal Response Mode" }, + { XDLC_TEST>>2, "Test" }, + { XDLC_SIM>>2, "Set Initialization Mode" }, + { XDLC_FRMR>>2, "Frame reject" }, + { XDLC_CFGR>>2, "Configure" }, + { XDLC_SARM>>2, "Set Asynchronous Response Mode" }, + { XDLC_SABM>>2, "Set Asynchronous Balanced Mode" }, + { XDLC_SARME>>2, "Set Asynchronous Response Mode Extended" }, + { XDLC_SABME>>2, "Set Asynchronous Balanced Mode Extended" }, + { XDLC_RESET>>2, "Reset" }, + { XDLC_XID>>2, "Exchange identification" }, + { XDLC_SNRME>>2, "Set Normal Response Mode Extended" }, + { XDLC_BCN>>2, "Beacon" }, + { 0, NULL } }; static const value_string modifier_short_vals_resp[] = { @@ -133,25 +113,25 @@ static const value_string modifier_short_vals_resp[] = { { 0, NULL } }; -static const value_string modifier_vals_resp[] = { - { XDLC_UI, "Unnumbered Information" }, - { XDLC_UP, "Unnumbered Poll" }, - { XDLC_RD, "Request Disconnect" }, - { XDLC_UA, "Unnumbered Acknowledge" }, - { XDLC_SNRM, "Set Normal Response Mode" }, - { XDLC_TEST, "Test" }, - { XDLC_RIM, "Request Initialization Mode" }, - { XDLC_FRMR, "Frame reject" }, - { XDLC_CFGR, "Configure" }, - { XDLC_DM, "Disconnected mode" }, - { XDLC_SABM, "Set Asynchronous Balanced Mode" }, - { XDLC_SARME, "Set Asynchronous Response Mode Extended" }, - { XDLC_SABME, "Set Asynchronous Balanced Mode Extended" }, - { XDLC_RESET, "Reset" }, - { XDLC_XID, "Exchange identification" }, - { XDLC_SNRME, "Set Normal Response Mode Extended" }, - { XDLC_BCN, "Beacon" }, - { 0, NULL } +const value_string modifier_vals_resp[] = { + { XDLC_UI>>2, "Unnumbered Information" }, + { XDLC_UP>>2, "Unnumbered Poll" }, + { XDLC_RD>>2, "Request Disconnect" }, + { XDLC_UA>>2, "Unnumbered Acknowledge" }, + { XDLC_SNRM>>2, "Set Normal Response Mode" }, + { XDLC_TEST>>2, "Test" }, + { XDLC_RIM>>2, "Request Initialization Mode" }, + { XDLC_FRMR>>2, "Frame reject" }, + { XDLC_CFGR>>2, "Configure" }, + { XDLC_DM>>2, "Disconnected mode" }, + { XDLC_SABM>>2, "Set Asynchronous Balanced Mode" }, + { XDLC_SARME>>2, "Set Asynchronous Response Mode Extended" }, + { XDLC_SABME>>2, "Set Asynchronous Balanced Mode Extended" }, + { XDLC_RESET>>2, "Reset" }, + { XDLC_XID>>2, "Exchange identification" }, + { XDLC_SNRME>>2, "Set Normal Response Mode Extended" }, + { XDLC_BCN>>2, "Beacon" }, + { 0, NULL } }; int @@ -192,9 +172,14 @@ get_xdlc_control(const guchar *pd, int offset, int is_extended) 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, int is_response, int is_extended, int append_info) { guint16 control; + int control_len; + const xdlc_cf_items *cf_items; + char *control_format; + guint16 poll_final; char info[80]; proto_tree *tc, *control_tree; gchar *frame_type = NULL; @@ -203,13 +188,20 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, switch (tvb_get_guint8(tvb, offset) & 0x03) { case XDLC_S: + if (is_extended) { + control = tvb_get_letohs(tvb, offset); + control_len = 2; + cf_items = cf_items_ext; + control_format = "Control field: %s (0x%04X)"; + } else { + control = tvb_get_guint8(tvb, offset); + control_len = 1; + cf_items = cf_items_nonext; + control_format = "Control field: %s (0x%02X)"; + } /* * Supervisory frame. */ - if (is_extended) - control = tvb_get_letohs(tvb, offset); - else - control = tvb_get_guint8(tvb, offset); switch (control & XDLC_S_FTYPE_MASK) { case XDLC_RR: frame_type = "RR"; @@ -228,14 +220,16 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, break; } if (is_extended) { + poll_final = (control & XDLC_P_F_EXT); sprintf(info, "S%s, %sN(R) = %u", frame_type, - ((control & XDLC_P_F_EXT) ? + (poll_final ? (is_response ? "func = F, " : "func = P, ") : ""), (control & XDLC_N_R_EXT_MASK) >> XDLC_N_R_EXT_SHIFT); } else { + poll_final = (control & XDLC_P_F); sprintf(info, "S%s, %sN(R) = %u", frame_type, - ((control & XDLC_P_F) ? + (poll_final ? (is_response ? "func = F, " : "func = P, ") : ""), (control & XDLC_N_R_MASK) >> XDLC_N_R_SHIFT); @@ -248,49 +242,22 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, col_add_str(pinfo->cinfo, COL_INFO, info); } if (xdlc_tree) { - if (is_extended) { - tc = proto_tree_add_uint_format(xdlc_tree, hf_xdlc_control, tvb, - offset, 2, - control, - "Control field: %s (0x%04X)", info, control); - control_tree = proto_item_add_subtree(tc, ett_xdlc_control); - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_numeric_bitfield(control, XDLC_N_R_EXT_MASK, 2*8, - "N(R) = %u")); - if (control & XDLC_P_F_EXT) { - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_boolean_bitfield(control, XDLC_P_F_EXT, 2*8, - (is_response ? "Final" : "Poll"), NULL)); - } - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_enumerated_bitfield(control, XDLC_S_FTYPE_MASK, 2*8, - stype_vals, "Supervisory frame - %s")); - /* This will always say it's a supervisory frame */ - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_boolean_bitfield(control, 0x03, 2*8, - "Supervisory frame", NULL)); - } else { - tc = proto_tree_add_uint_format(xdlc_tree, hf_xdlc_control, tvb, - offset, 1, - control, - "Control field: %s (0x%02X)", info, control); - control_tree = proto_item_add_subtree(tc, ett_xdlc_control); - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_numeric_bitfield(control, XDLC_N_R_MASK, 1*8, - "N(R) = %u")); - if (control & XDLC_P_F) { - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_boolean_bitfield(control, XDLC_P_F, 1*8, - (is_response ? "Final" : "Poll"), NULL)); - } - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_enumerated_bitfield(control, XDLC_S_FTYPE_MASK, 1*8, - stype_vals, "%s")); - /* This will always say it's a supervisory frame */ - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_boolean_bitfield(control, 0x03, 1*8, - "Supervisory frame", NULL)); + tc = proto_tree_add_uint_format(xdlc_tree, hf_xdlc_control, tvb, + offset, control_len, control, control_format, info, control); + control_tree = proto_item_add_subtree(tc, ett_xdlc_control); + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_n_r, + tvb, offset, control_len, control); + if (poll_final) { + proto_tree_add_boolean(control_tree, + (is_response ? *cf_items->hf_xdlc_f : + *cf_items->hf_xdlc_p), + tvb, offset, control_len, control); } + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_s_ftype, + tvb, offset, control_len, control); + /* This will always say it's a supervisory frame */ + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_ftype_s_u, + tvb, offset, control_len, control); } break; @@ -306,6 +273,9 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, * need for it to be 2 bytes in extended operation. */ control = tvb_get_guint8(tvb, offset); + control_len = 1; + cf_items = cf_items_nonext; + control_format = "Control field: %s (0x%02X)"; if (is_response) { modifier = match_strval(control & XDLC_U_MODIFIER_MASK, modifier_short_vals_resp); @@ -315,8 +285,9 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, } if (modifier == NULL) modifier = "Unknown"; + poll_final = (control & XDLC_P_F); sprintf(info, "U%s, func = %s", - ((control & XDLC_P_F) ? + (poll_final ? (is_response ? " F" : " P") : ""), modifier); @@ -328,24 +299,22 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, col_add_str(pinfo->cinfo, COL_INFO, info); } if (xdlc_tree) { - tc = proto_tree_add_uint_format(xdlc_tree, hf_xdlc_control, tvb, - offset, 1, - control, - "Control field: %s (0x%02X)", info, control); + tc = proto_tree_add_uint_format(xdlc_tree, hf_xdlc_control, tvb, + offset, control_len, control, control_format, info, control); control_tree = proto_item_add_subtree(tc, ett_xdlc_control); - if (control & XDLC_P_F) { - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_boolean_bitfield(control, XDLC_P_F, 1*8, - (is_response ? "Final" : "Poll"), NULL)); + if (poll_final) { + proto_tree_add_boolean(control_tree, + (is_response ? *cf_items->hf_xdlc_f: + *cf_items->hf_xdlc_p), + tvb, offset, control_len, control); } - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_enumerated_bitfield(control, XDLC_U_MODIFIER_MASK, 1*8, - (is_response ? modifier_vals_resp : modifier_vals_cmd), - "%s")); + proto_tree_add_uint(control_tree, + (is_response ? *cf_items->hf_xdlc_u_modifier_resp : + *cf_items->hf_xdlc_u_modifier_cmd), + tvb, offset, control_len, control); /* This will always say it's an unnumbered frame */ - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_boolean_bitfield(control, 0x03, 1*8, - "Unnumbered frame", NULL)); + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_ftype_s_u, + tvb, offset, control_len, control); } break; @@ -353,16 +322,22 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, /* * Information frame. */ - if (is_extended) - control = tvb_get_letohs(tvb, offset); - else - control = tvb_get_guint8(tvb, offset); if (is_extended) { + control = tvb_get_letohs(tvb, offset); + control_len = 2; + cf_items = cf_items_ext; + control_format = "Control field: %s (0x%04X)"; + poll_final = (control & XDLC_P_F_EXT); sprintf(info, "I%s, N(R) = %u, N(S) = %u", ((control & XDLC_P_F_EXT) ? " P" : ""), (control & XDLC_N_R_EXT_MASK) >> XDLC_N_R_EXT_SHIFT, (control & XDLC_N_S_EXT_MASK) >> XDLC_N_S_EXT_SHIFT); } else { + control = tvb_get_guint8(tvb, offset); + control_len = 1; + cf_items = cf_items_nonext; + control_format = "Control field: %s (0x%02X)"; + poll_final = (control & XDLC_P_F); sprintf(info, "I%s, N(R) = %u, N(S) = %u", ((control & XDLC_P_F) ? " P" : ""), (control & XDLC_N_R_MASK) >> XDLC_N_R_SHIFT, @@ -377,46 +352,21 @@ dissect_xdlc_control(tvbuff_t *tvb, int offset, packet_info *pinfo, } if (xdlc_tree) { tc = proto_tree_add_uint_format(xdlc_tree, hf_xdlc_control, tvb, - offset, (is_extended) ? 2 : 1, - control, - (is_extended) ? "Control field: %s (0x%04X)" - : "Control field: %s (0x%02X)", - info, control); + offset, control_len, control, control_format, info, control); control_tree = proto_item_add_subtree(tc, ett_xdlc_control); - if (is_extended) { - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_numeric_bitfield(control, XDLC_N_R_EXT_MASK, 2*8, - "N(R) = %u")); - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_numeric_bitfield(control, XDLC_N_S_EXT_MASK, 2*8, - "N(S) = %u")); - if (control & XDLC_P_F_EXT) { - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_boolean_bitfield(control, XDLC_P_F_EXT, 2*8, - "Poll", NULL)); - } - /* This will always say it's an information frame */ - proto_tree_add_text(control_tree, tvb, offset, 2, - decode_boolean_bitfield(control, 0x01, 2*8, - NULL, "Information frame")); - } else { - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_numeric_bitfield(control, XDLC_N_R_MASK, 1*8, - "N(R) = %u")); - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_numeric_bitfield(control, XDLC_N_S_MASK, 1*8, - "N(S) = %u")); - if (control & XDLC_P_F) { - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_boolean_bitfield(control, XDLC_P_F, 1*8, - "Poll", NULL)); - } - /* This will always say it's an information frame */ - proto_tree_add_text(control_tree, tvb, offset, 1, - decode_boolean_bitfield(control, 0x01, 1*8, - NULL, "Information frame")); + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_n_r, + tvb, offset, control_len, control); + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_n_s, + tvb, offset, control_len, control); + if (poll_final) { + proto_tree_add_boolean(control_tree, *cf_items->hf_xdlc_p, + tvb, offset, control_len, control); } + /* This will always say it's an information frame */ + proto_tree_add_uint(control_tree, *cf_items->hf_xdlc_ftype_i, + tvb, offset, control_len, control); } + break; } return control; } |