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wireshark/packet-fr.c
Guy Harris ee5ca25d31 Include files from the "epan" directory and subdirectories thereof with 
"epan/..." pathnames, so as to avoid collisions with header files in any
of the directories in which we look (e.g., "proto.h", as some other
package has its own "proto.h" file which it installs in the top-level
include directory).

Don't add "-I" flags to search "epan", as that's no longer necessary
(and we want includes of "epan" headers to fail if the "epan/" is left
out, so that we don't re-introduce includes lacking "epan/").

svn path=/trunk/; revision=4586
2002-01-21 07:37:49 +00:00

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/* packet-fr.c
* Routines for Frame Relay dissection
*
* Copyright 2001, Paul Ionescu <paul@acorp.ro>
*
* $Id: packet-fr.c,v 1.28 2002/01/21 07:36:34 guy Exp $
*
* 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.
*
* References:
*
* http://www.protocols.com/pbook/frame.htm
* http://www.frforum.com/5000/Approved/FRF.3/FRF.3.2.pdf
* ITU Recommendation Q.933
* RFC-1490
* RFC-2427
* Cisco encapsulation
* http://www.trillium.com/whats-new/wp_frmrly.html
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <glib.h>
#include <epan/packet.h>
#include "packet-osi.h"
#include "packet-llc.h"
#include "packet-chdlc.h"
#include "xdlc.h"
#include "etypes.h"
#include "oui.h"
#include "nlpid.h"
#include "greproto.h"
#include <epan/conversation.h>
/*
* Bits in the address field.
*/
#define FRELAY_DLCI 0xfcf0 /* 2 byte DLCI Address */
#define FRELAY_CR 0x0200 /* Command/Response bit */
#define FRELAY_EA 0x0001 /* Address Extension bit */
#define FRELAY_FECN 0x0008 /* Forward Explicit Congestion Notification */
#define FRELAY_BECN 0x0004 /* Backward Explicit Congestion Notification */
#define FRELAY_DE 0x0002 /* Discard Eligibility */
#define FRELAY_DC 0x0002 /* Control bits */
/*
* Extract the DLCI from the address field.
*/
#define EXTRACT_DLCI(addr) ((((addr)&0xfc00) >> 6) | (((addr)&0xf0) >> 4))
#define FROM_DCE 0x80 /* for direction setting */
static gint proto_fr = -1;
static gint ett_fr = -1;
static gint hf_fr_dlci = -1;
static gint hf_fr_cr = -1;
static gint hf_fr_becn = -1;
static gint hf_fr_fecn = -1;
static gint hf_fr_de = -1;
static gint hf_fr_ea = -1;
static gint hf_fr_dc = -1;
static gint hf_fr_nlpid = -1;
static gint hf_fr_oui = -1;
static gint hf_fr_pid = -1;
static gint hf_fr_snaptype = -1;
static gint hf_fr_chdlctype = -1;
static dissector_handle_t data_handle;
static const true_false_string cmd_string = {
"Command",
"Response"
};
static const true_false_string ctrl_string = {
"DLCI Address",
"Control"
};
static const true_false_string ea_string = {
"Last Octet",
"More Follows"
};
/*
* This isn't the same as "nlpid_vals[]"; 0x08 is Q.933, not Q.931,
* and 0x09 is LMI, not Q.2931, and we assume that it's an initial
* protocol identifier, so 0x01 is T.70, not X.29.
*/
static const value_string fr_nlpid_vals[] = {
{ NLPID_NULL, "NULL" },
{ NLPID_IPI_T_70, "T.70" }, /* XXX - IPI, or SPI? */
{ NLPID_X_633, "X.633" },
{ NLPID_Q_931, "Q.933" },
{ NLPID_LMI, "LMI" },
{ NLPID_Q_2119, "Q.2119" },
{ NLPID_SNAP, "SNAP" },
{ NLPID_ISO8473_CLNP, "CLNP" },
{ NLPID_ISO9542_ESIS, "ESIS" },
{ NLPID_ISO10589_ISIS, "ISIS" },
{ NLPID_ISO10747_IDRP, "IDRP" },
{ NLPID_ISO9542X25_ESIS, "ESIS (X.25)" },
{ NLPID_ISO10030, "ISO 10030" },
{ NLPID_ISO11577, "ISO 11577" },
{ NLPID_COMPRESSED, "Data compression protocol" },
{ NLPID_IP, "IP" },
{ NLPID_IP6, "IPv6" },
{ NLPID_PPP, "PPP" },
{ 0, NULL },
};
static dissector_table_t fr_subdissector_table;
static void dissect_fr_nlpid(tvbuff_t *tvb, int offset, packet_info *pinfo,
proto_tree *tree, proto_item *ti,
proto_tree *fr_tree, guint8 fr_ctrl);
static void dissect_lapf(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
static void dissect_fr_xid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree);
static void dissect_fr(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_item *ti = NULL;
proto_tree *fr_tree = NULL;
guint16 fr_header,fr_type,offset=2; /* default header length of FR is 2 bytes */
guint16 address;
char buf[32];
guint8 fr_ctrl;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
col_set_str(pinfo->cinfo, COL_PROTOCOL, "FR");
if (pinfo->pseudo_header->x25.flags & FROM_DCE) {
if(check_col(pinfo->cinfo, COL_RES_DL_DST))
col_set_str(pinfo->cinfo, COL_RES_DL_DST, "DTE");
if(check_col(pinfo->cinfo, COL_RES_DL_SRC))
col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "DCE");
}
else {
if(check_col(pinfo->cinfo, COL_RES_DL_DST))
col_set_str(pinfo->cinfo, COL_RES_DL_DST, "DCE");
if(check_col(pinfo->cinfo, COL_RES_DL_SRC))
col_set_str(pinfo->cinfo, COL_RES_DL_SRC, "DTE");
}
/*XXX We should check the EA bits and use that to generate the address. */
fr_header = tvb_get_ntohs(tvb, 0);
fr_ctrl = tvb_get_guint8( tvb, 2);
address = EXTRACT_DLCI(fr_header);
if (check_col(pinfo->cinfo, COL_INFO))
col_add_fstr(pinfo->cinfo, COL_INFO, "DLCI %u", address);
if (tree) {
ti = proto_tree_add_protocol_format(tree, proto_fr, tvb, 0, 3, "Frame Relay");
fr_tree = proto_item_add_subtree(ti, ett_fr);
decode_bitfield_value(buf, fr_header, FRELAY_DLCI, 16);
proto_tree_add_uint_format(fr_tree, hf_fr_dlci, tvb, 0, 2, address,
"%sDLCI: %u", buf, address);
proto_tree_add_boolean(fr_tree, hf_fr_cr, tvb, 0, offset, fr_header);
proto_tree_add_boolean(fr_tree, hf_fr_fecn, tvb, 0, offset, fr_header);
proto_tree_add_boolean(fr_tree, hf_fr_becn, tvb, 0, offset, fr_header);
proto_tree_add_boolean(fr_tree, hf_fr_de, tvb, 0, offset, fr_header);
proto_tree_add_boolean(fr_tree, hf_fr_ea, tvb, 0, offset, fr_header);
}
if (fr_ctrl == XDLC_U) {
if (tree) {
proto_tree_add_text(fr_tree, tvb, offset, 0, "------- Q.933 Encapsulation -------");
/*
* XXX - if we're going to show this as Unnumbered
* Information, should we just hand it to
* "dissect_xdlc_control()"?
*/
proto_tree_add_text(fr_tree, tvb, offset, 1, "Unnumbered Information");
}
offset++;
SET_ADDRESS(&pinfo->dl_src, AT_DLCI, 2, (guint8*)&address);
dissect_fr_nlpid(tvb, offset, pinfo, tree, ti, fr_tree, fr_ctrl);
} else {
if (address == 0) {
/* this must be some sort of lapf on DLCI 0 for SVC */
/* because DLCI 0 is rezerved for LMI and SVC signaling encaplulated in lapf */
/* and LMI is transmitted in unnumbered information (03) */
/* so this must be lapf (guessing) */
dissect_lapf(tvb_new_subset(tvb,offset,-1,-1),pinfo,tree);
return;
}
if (fr_ctrl == (XDLC_U|XDLC_XID)) {
dissect_fr_xid(tvb_new_subset(tvb,offset,-1,-1),pinfo,tree);
return;
}
/*
* If the data does not start with unnumbered information (03) and
* the DLCI# is not 0, then there may be Cisco Frame Relay encapsulation.
*/
proto_tree_add_text(fr_tree, tvb, offset, 0, "------- Cisco Encapsulation -------");
fr_type = tvb_get_ntohs(tvb, offset);
if (ti != NULL) {
/* Include the Cisco HDLC type in the top-level protocol
tree item. */
proto_item_set_len(ti, offset+2);
}
chdlctype(fr_type, tvb, offset+2, pinfo, tree, fr_tree, hf_fr_chdlctype);
}
}
static void dissect_fr_uncompressed(tvbuff_t *tvb, packet_info *pinfo,
proto_tree *tree)
{
proto_item *ti = NULL;
proto_tree *fr_tree = NULL;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
col_set_str(pinfo->cinfo, COL_PROTOCOL, "FR");
if (check_col(pinfo->cinfo, COL_INFO))
col_clear(pinfo->cinfo, COL_INFO);
if (tree) {
ti = proto_tree_add_protocol_format(tree, proto_fr, tvb, 0, 4, "Frame Relay");
fr_tree = proto_item_add_subtree(ti, ett_fr);
}
dissect_fr_nlpid(tvb, 0, pinfo, tree, ti, fr_tree, XDLC_U);
}
static void dissect_fr_nlpid(tvbuff_t *tvb, int offset, packet_info *pinfo,
proto_tree *tree, proto_item *ti,
proto_tree *fr_tree, guint8 fr_ctrl)
{
guint8 fr_nlpid;
tvbuff_t *next_tvb;
fr_nlpid = tvb_get_guint8 (tvb,offset);
if (fr_nlpid == 0) {
if (tree)
proto_tree_add_text(fr_tree, tvb, offset, 1, "Padding");
offset++;
if (ti != NULL) {
/* Include the padding in the top-level protocol tree item. */
proto_item_set_len(ti, offset);
}
fr_nlpid=tvb_get_guint8( tvb,offset);
}
/*
* OSI network layer protocols consider the NLPID to be part
* of the frame, so we'll pass it as part of the payload and,
* if the protocol is one of those, add it as a hidden item here.
*/
next_tvb = tvb_new_subset(tvb,offset,-1,-1);
if (dissector_try_port(osinl_subdissector_table, fr_nlpid, next_tvb,
pinfo, tree)) {
/*
* Yes, we got a match. Add the NLPID as a hidden item,
* so you can, at least, filter on it.
*/
if (tree)
proto_tree_add_uint_hidden(fr_tree, hf_fr_nlpid,
tvb, offset, 1, fr_nlpid );
return;
}
/*
* All other protocols don't.
*
* XXX - not true for Q.933 and LMI, but we don't yet have a
* Q.933 dissector (it'd be similar to the Q.931 dissector,
* but I don't think it'd be identical, although it's less
* different than is the Q.2931 dissector), and the LMI
* dissector doesn't yet put the protocol discriminator
* (NLPID) into the tree.
*
* Note that an NLPID of 0x08 for Q.933 could either be a
* Q.933 signaling message or a message for a protocol
* identified by a 2-octet layer 2 protocol type and a
* 2-octet layer 3 protocol type, those protocol type
* octets having the values from octets 6, 6a, 7, and 7a
* of a Q.931 low layer compatibility information element
* (section 4.5.19 of Q.931; Q.933 says they have the values
* from a Q.933 low layer compatibility information element,
* but Q.933 low layer compatibility information elements
* don't have protocol values in them).
*
* Assuming that, as Q.933 seems to imply, that Q.933 messages
* look just like Q.931 messages except where it explicitly
* says they differ, then the octet after the NLPID would,
* in a Q.933 message, have its upper 4 bits zero (that's
* the length of the call reference value, in Q.931, and
* is limited to 15 or fewer octets). As appears to be the case,
* octet 6 of a Q.931 low layer compatibility element has the
* 0x40 bit set, so you can distinguish between a Q.933
* message and an encapsulated packet by checking whether
* the upper 4 bits of the octet after the NLPID are zero.
*
* To handle this, we'd handle Q.933's NLPID specially, which
* we'd want to do anyway, so that we give it a tvbuff that
* includes the NLPID.
*/
if (tree)
proto_tree_add_uint(fr_tree, hf_fr_nlpid, tvb, offset, 1, fr_nlpid );
offset++;
switch (fr_nlpid) {
case NLPID_SNAP:
if (ti != NULL) {
/* Include the NLPID and SNAP header in the top-level
protocol tree item. */
proto_item_set_len(ti, offset+5);
}
dissect_snap(tvb, offset, pinfo, tree, fr_tree, fr_ctrl,
hf_fr_oui, hf_fr_snaptype, hf_fr_pid, 0);
return;
default:
if (ti != NULL) {
/* Include the NLPID in the top-level protocol tree item. */
proto_item_set_len(ti, offset);
}
next_tvb = tvb_new_subset(tvb,offset,-1,-1);
if (!dissector_try_port(fr_subdissector_table,fr_nlpid,
next_tvb, pinfo, tree))
call_dissector(data_handle,next_tvb, pinfo, tree);
break;
}
}
static void dissect_lapf(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree_add_text(tree, tvb, 0, 0, "Frame relay lapf not yet implemented");
call_dissector(data_handle,tvb_new_subset(tvb,0,-1,-1),pinfo,tree);
}
static void dissect_fr_xid(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree_add_text(tree, tvb, 0, 0, "Frame relay xid not yet implemented");
call_dissector(data_handle,tvb_new_subset(tvb,0,-1,-1),pinfo,tree);
}
/* Register the protocol with Ethereal */
void proto_register_fr(void)
{
static hf_register_info hf[] = {
{ &hf_fr_dlci, {
"DLCI", "fr.dlci", FT_UINT16, BASE_DEC,
NULL, FRELAY_DLCI, "Data-Link Connection Identifier", HFILL }},
{ &hf_fr_cr, {
"CR", "fr.cr", FT_BOOLEAN, 16, TFS(&cmd_string),
FRELAY_CR, "Command/Response", HFILL }},
{ &hf_fr_dc, {
"DC", "fr.dc", FT_BOOLEAN, 16, TFS(&ctrl_string),
FRELAY_CR, "Address/Control", HFILL }},
{ &hf_fr_fecn, {
"FECN", "fr.fecn", FT_BOOLEAN, 16,
NULL, FRELAY_FECN, "Forward Explicit Congestion Notification", HFILL }},
{ &hf_fr_becn, {
"BECN", "fr.becn", FT_BOOLEAN, 16,
NULL, FRELAY_BECN, "Backward Explicit Congestion Notification", HFILL }},
{ &hf_fr_de, {
"DE", "fr.de", FT_BOOLEAN, 16,
NULL, FRELAY_DE, "Discard Eligibility", HFILL }},
{ &hf_fr_ea, {
"EA", "fr.ea", FT_BOOLEAN, 16, TFS(&ea_string),
FRELAY_EA, "Extended Address", HFILL }},
{ &hf_fr_nlpid, {
"NLPID", "fr.nlpid", FT_UINT8, BASE_HEX,
VALS(fr_nlpid_vals), 0x0, "FrameRelay Encapsulated Protocol NLPID", HFILL }},
{ &hf_fr_oui, {
"Organization Code", "fr.snap.oui", FT_UINT24, BASE_HEX,
VALS(oui_vals), 0x0, "", HFILL }},
{ &hf_fr_pid, {
"Protocol ID", "fr.snap.pid", FT_UINT16, BASE_HEX,
NULL, 0x0, "", HFILL }},
{ &hf_fr_snaptype, {
"Type", "fr.snaptype", FT_UINT16, BASE_HEX,
VALS(etype_vals), 0x0, "FrameRelay SNAP Encapsulated Protocol", HFILL }},
{ &hf_fr_chdlctype, {
"Type", "fr.chdlctype", FT_UINT16, BASE_HEX,
VALS(chdlc_vals), 0x0, "FrameRelay Cisco HDLC Encapsulated Protocol", HFILL }},
};
/* Setup protocol subtree array */
static gint *ett[] = {
&ett_fr,
};
proto_fr = proto_register_protocol("Frame Relay", "FR", "fr");
proto_register_field_array(proto_fr, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
fr_subdissector_table = register_dissector_table("fr.ietf",
"Frame Relay NLPID", FT_UINT8, BASE_HEX);
register_dissector("fr", dissect_fr_uncompressed, proto_fr);
}
void proto_reg_handoff_fr(void)
{
dissector_handle_t fr_handle;
fr_handle = create_dissector_handle(dissect_fr, proto_fr);
dissector_add("wtap_encap", WTAP_ENCAP_FRELAY, fr_handle);
dissector_add("gre.proto", GRE_FR, fr_handle);
data_handle = find_dissector("data");
}
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