Add a new Wiretap encapsulation type for Cisco HDLC. Map the NetBSD

DLT_HDLC to it.

Make a separate dissector for Cisco HDLC, and add a dissector for Cisco
SLARP.  Have the PPP dissector call the Cisco HDLC dissector if the
address field is the Cisco HDLC unicast or multicast address.  Use the
Cisco HDLC dissector for the Cisco HDLC Wiretap encapsulation type.

Add a new dissector table "chdlctype", for Cisco HDLC packet types
(they're *almost* the same as Ethernet types, but 0x8035 is SLARP, not
Reverse ARP, and 0x2000 is the Cisco Discovery protocol, for example),
replacing "fr.chdlc".

Have a "chdlctype()" routine, similar to "ethertype()", used both by the
Cisco HDLC and Frame Relay dissectors.  Have a "chdlc_vals[]"
"value_string" table for Cisco HDLC types and protocol names.  Split the
packet type field in the Frame Relay dissector into separate SNAP and
Cisco HDLC fields, and give them the Ethernet type and Cisco HDLC type
"value_string" tables, respectively.

svn path=/trunk/; revision=3133

1 files changed, 306 insertions, 0 deletions

diff --git a/packet-chdlc.c b/packet-chdlc.c
new file mode 100644
index 0000000000..7c5d6d64aa
--- /dev/null
+++ b/packet-chdlc.c
@@ -0,0 +1,306 @@
+/* packet-chdlc.c
+ * Routines for Cisco HDLC packet disassembly
+ *
+ * $Id: packet-chdlc.c,v 1.1 2001/03/15 09:11:00 guy Exp $
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@zing.org>
+ *
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+
+#include <glib.h>
+#include "packet.h"
+#include "etypes.h"
+#include "resolv.h"
+#include "packet-chdlc.h"
+#include "packet-ip.h"
+
+/*
+ * See section 4.3.1 of RFC 1547, and
+ *
+ *	http://www.nethelp.no/net/cisco-hdlc.txt
+ */
+
+static int proto_chdlc = -1;
+static int hf_chdlc_addr = -1;
+static int hf_chdlc_proto = -1;
+
+static gint ett_chdlc = -1;
+
+static int proto_slarp = -1;
+static int hf_slarp_ptype = -1;
+static int hf_slarp_address = -1;
+static int hf_slarp_mysequence = -1;
+static int hf_slarp_yoursequence = -1;
+
+static gint ett_slarp = -1;
+
+/*
+ * Protocol types for the Cisco HDLC format.
+ *
+ * As per the above, according to RFC 1547, these are "standard 16 bit
+ * Ethernet protocol type code[s]", but 0x8035 is Reverse ARP, and
+ * that is (at least according to the Linux ISDN code) not the
+ * same as Cisco SLARP.
+ *
+ * In addition, 0x2000 is apparently the Cisco Discovery Protocol, but
+ * on Ethernet those are encapsulated inside SNAP with an OUI of
+ * OUI_CISCO, not OUI_ENCAP_ETHER.
+ *
+ * Perhaps we should set up a protocol table for those protocols
+ * that differ between Ethernet and Cisco HDLC, and have the PPP
+ * code first try that table and, if it finds nothing in that
+ * table, call "ethertype()".  (Unfortunately, that means that -
+ * assuming we had a Cisco SLARP dissector - said dissector were
+ * disabled, SLARP packets would be dissected as Reverse ARP
+ * packets, not as data.)
+ */
+#define CISCO_SLARP	0x8035	/* Cisco SLARP protocol */
+
+static dissector_table_t subdissector_table;
+
+static const value_string chdlc_address_vals[] = {
+	{CHDLC_ADDR_UNICAST,   "Unicast"},
+	{CHDLC_ADDR_MULTICAST, "Multicast"},
+	{0,                    NULL}
+};
+
+const value_string chdlc_vals[] = {
+	{0x2000,           "Cisco Discovery Protocol"},
+	{ETHERTYPE_IP,     "IP"},
+	{CISCO_SLARP,      "SLARP"},
+	{ETHERTYPE_DEC_LB, "DEC LanBridge"},
+	{ETHERTYPE_ATALK,  "Appletalk"},
+	{ETHERTYPE_AARP,   "AARP"},
+	{ETHERTYPE_IPX,    "Netware IPX/SPX"},
+	{0,                NULL}
+};
+
+void
+capture_chdlc( const u_char *pd, int offset, packet_counts *ld ) {
+  switch (pntohs(&pd[offset + 2])) {
+    case ETHERTYPE_IP:
+      capture_ip(pd, offset + 4, ld);
+      break;
+    default:
+      ld->other++;
+      break;
+  }
+}
+
+void
+chdlctype(guint16 chdlctype, tvbuff_t *tvb, int offset_after_chdlctype,
+	  packet_info *pinfo, proto_tree *tree, proto_tree *fh_tree,
+	  int chdlctype_id)
+{
+  tvbuff_t   *next_tvb;
+
+  if (tree) {
+    proto_tree_add_uint(fh_tree, chdlctype_id, tvb,
+			offset_after_chdlctype - 2, 2, chdlctype);
+  }
+
+  next_tvb = tvb_new_subset(tvb, offset_after_chdlctype, -1, -1);
+
+  /* do lookup with the subdissector table */
+  if (!dissector_try_port(subdissector_table, chdlctype, next_tvb, pinfo, tree)) {
+    if (check_col(pinfo->fd, COL_PROTOCOL))
+      col_add_fstr(pinfo->fd, COL_PROTOCOL, "0x%04x", chdlctype);
+    dissect_data(next_tvb, 0, pinfo, tree);
+  }
+}
+
+static void
+dissect_chdlc(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  proto_item *ti;
+  proto_tree *fh_tree = NULL;
+  guint8     addr;
+  guint16    proto;
+
+  if (check_col(pinfo->fd, COL_RES_DL_SRC))
+    col_set_str(pinfo->fd, COL_RES_DL_SRC, "N/A");
+  if (check_col(pinfo->fd, COL_RES_DL_DST))
+    col_set_str(pinfo->fd, COL_RES_DL_DST, "N/A");
+  if (check_col(pinfo->fd, COL_PROTOCOL))
+    col_set_str(pinfo->fd, COL_PROTOCOL, "CHDLC");
+  if (check_col(pinfo->fd, COL_INFO))
+    col_clear(pinfo->fd, COL_INFO);
+
+  addr = tvb_get_guint8(tvb, 0);
+  proto = tvb_get_ntohs(tvb, 2);
+
+  if (tree) {
+    ti = proto_tree_add_item(tree, proto_chdlc, tvb, 0, 4, FALSE);
+    fh_tree = proto_item_add_subtree(ti, ett_chdlc);
+
+    proto_tree_add_uint(fh_tree, hf_chdlc_addr, tvb, 0, 1, addr);
+  }
+
+  chdlctype(proto, tvb, 4, pinfo, tree, fh_tree, hf_chdlc_proto);
+}
+
+void
+proto_register_chdlc(void)
+{
+  static hf_register_info hf[] = {
+    { &hf_chdlc_addr,
+      { "Address", "chdlc.address", FT_UINT8, BASE_HEX,
+        VALS(chdlc_address_vals), 0x0, "" }},
+    { &hf_chdlc_proto,
+      { "Protocol", "chdlc.protocol", FT_UINT16, BASE_HEX,
+        VALS(chdlc_vals), 0x0, "" }},
+  };
+  static gint *ett[] = {
+    &ett_chdlc,
+  };
+
+  proto_chdlc = proto_register_protocol("Cisco HDLC", "CHDLC", "chdlc");
+  proto_register_field_array(proto_chdlc, hf, array_length(hf));
+  proto_register_subtree_array(ett, array_length(ett));
+
+/* subdissector code */
+  subdissector_table = register_dissector_table("chdlctype");
+
+  register_dissector("chdlc", dissect_chdlc, proto_chdlc);
+}
+
+void
+proto_reg_handoff_chdlc(void)
+{
+  dissector_add("wtap_encap", WTAP_ENCAP_CHDLC, dissect_chdlc, proto_chdlc);
+}
+
+#define SLARP_REQUEST	0
+#define SLARP_REPLY	1
+#define SLARP_LINECHECK	2
+
+static const value_string slarp_ptype_vals[] = {
+	{SLARP_REQUEST,   "Request"},
+	{SLARP_REPLY,     "Reply"},
+	{SLARP_LINECHECK, "Line keepalive"},
+	{0,               NULL}
+};
+
+static void
+dissect_slarp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+  proto_item *ti;
+  proto_tree *slarp_tree = NULL;
+  guint32 code;
+  guint32 mysequence;
+  guint32 yoursequence;
+
+  if (check_col(pinfo->fd, COL_PROTOCOL))
+    col_set_str(pinfo->fd, COL_PROTOCOL, "SLARP");
+  if (check_col(pinfo->fd, COL_INFO))
+    col_clear(pinfo->fd, COL_INFO);
+
+  code = tvb_get_ntohl(tvb, 0);
+
+  if (tree) {
+    ti = proto_tree_add_item(tree, proto_slarp, tvb, 0, 14, FALSE);
+    slarp_tree = proto_item_add_subtree(ti, ett_slarp);
+  }
+
+  switch (code) {
+
+  case SLARP_REQUEST:
+  case SLARP_REPLY:
+    if (check_col(pinfo->fd, COL_INFO)) {
+      col_add_fstr(pinfo->fd, COL_INFO, "%s, from %s, mask %s",
+        match_strval(code, slarp_ptype_vals),
+        get_hostname(tvb_get_ntohl(tvb, 4)),
+        ip_to_str(tvb_get_ptr(tvb, 8, 4)));
+    }
+    if (tree) {
+      proto_tree_add_uint(slarp_tree, hf_slarp_ptype, tvb, 0, 4, code);
+      proto_tree_add_item(slarp_tree, hf_slarp_address, tvb, 4, 4, FALSE);
+      proto_tree_add_text(slarp_tree, tvb, 8, 4,
+			  "Netmask: %s", ip_to_str(tvb_get_ptr(tvb, 8, 4)));
+    }
+    break;
+
+  case SLARP_LINECHECK:
+    mysequence = tvb_get_ntohl(tvb, 4);
+    yoursequence = tvb_get_ntohl(tvb, 8);
+    if (check_col(pinfo->fd, COL_INFO)) {
+      col_add_fstr(pinfo->fd, COL_INFO,
+        "%s, outgoing sequence %u, returned sequence %u",
+	match_strval(code, slarp_ptype_vals),
+        mysequence, yoursequence);
+    }
+    if (tree) {
+      proto_tree_add_uint(slarp_tree, hf_slarp_ptype, tvb, 0, 4, code);
+      proto_tree_add_uint(slarp_tree, hf_slarp_mysequence, tvb, 4, 4,
+			  mysequence);
+      proto_tree_add_uint(slarp_tree, hf_slarp_mysequence, tvb, 8, 4,
+			  yoursequence);
+    }
+    break;
+
+  default:
+    if (check_col(pinfo->fd, COL_INFO))
+      col_add_fstr(pinfo->fd, COL_INFO, "Unknown packet type 0x%08X", code);
+    if (tree) {
+      proto_tree_add_uint(slarp_tree, hf_slarp_ptype, tvb, 0, 4, code);
+      dissect_data(tvb, 4, pinfo, slarp_tree);
+    }
+    break;
+  }
+}
+
+void
+proto_register_slarp(void)
+{
+  static hf_register_info hf[] = {
+    { &hf_slarp_ptype,
+      { "Packet type", "slarp.ptype", FT_UINT32, BASE_DEC,
+        VALS(slarp_ptype_vals), 0x0, "" }},
+    { &hf_slarp_address,
+      { "Address", "slarp.address", FT_IPv4, BASE_NONE,
+        NULL, 0x0, "" }},
+    /* XXX - need an FT_ for netmasks, which is like FT_IPV4 but doesn't
+       get translated to a host name. */
+    { &hf_slarp_mysequence,
+      { "Outgoing sequence number", "slarp.mysequence", FT_UINT32, BASE_DEC,
+        NULL, 0x0, "" }},
+    { &hf_slarp_yoursequence,
+      { "Returned sequence number", "slarp.yoursequence", FT_UINT32, BASE_DEC,
+        NULL, 0x0, "" }},
+  };
+  static gint *ett[] = {
+    &ett_chdlc,
+  };
+
+  proto_slarp = proto_register_protocol("Cisco SLARP", "SLARP", "slarp");
+  proto_register_field_array(proto_slarp, hf, array_length(hf));
+  proto_register_subtree_array(ett, array_length(ett));
+}
+
+void
+proto_reg_handoff_slarp(void)
+{
+  dissector_add("chdlctype", CISCO_SLARP, dissect_slarp, proto_slarp);
+}