Added PPPoE, PPTP, GRE, and ISAKMP dissectors.

svn path=/trunk/; revision=303

1 files changed, 237 insertions, 0 deletions

diff --git a/packet-gre.c b/packet-gre.c
new file mode 100644
index 0000000000..c03d8ddcbf
--- /dev/null
+++ b/packet-gre.c
@@ -0,0 +1,237 @@
+/* packet-gre.c
+ * Routines for the Generic Routing Encapsulation (GRE) protocol
+ * Brad Robel-Forrest <brad.robel-forrest@watchguard.com>
+ *
+ * $Id: packet-gre.c,v 1.1 1999/06/11 15:30:37 gram Exp $
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@unicom.net>
+ * 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.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+
+#include <netinet/in.h>
+#include <glib.h>
+#include "packet.h"
+
+/* bit positions for flags in header */
+#define GH_B_C		0x8000
+#define GH_B_R		0x4000
+#define GH_B_K		0x2000
+#define GH_B_S		0x1000
+#define GH_B_s		0x0800
+#define GH_B_RECUR	0x0700
+#define GH_P_A		0x0080	/* only in special PPTPized GRE header */
+#define GH_P_FLAGS	0x0078	/* only in special PPTPized GRE header */
+#define GH_R_FLAGS	0x00F8
+#define GH_B_VER	0x0007
+
+#define GRE_PPP		0x880B
+
+static int calc_len(guint16, int);
+static void add_flags_and_ver(proto_tree *, guint16, int, int);
+
+void
+dissect_gre(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
+  
+  guint16	flags_and_ver = pntohs(pd + offset);
+  guint16	type	      = pntohs(pd + offset + sizeof(flags_and_ver));
+  static const value_string typevals[] = {
+    { GRE_PPP, "PPP" },
+    { 0,       NULL  }
+  };
+
+  if (check_col(fd, COL_PROTOCOL))
+    col_add_str(fd, COL_PROTOCOL, "GRE");
+	
+  if (check_col(fd, COL_INFO)) {
+    if (type == GRE_PPP)
+      col_add_str(fd, COL_INFO, "Encapsulated PPP");
+    else
+      col_add_str(fd, COL_INFO, "Encapsulated unknown");
+  }
+		
+  if (fd->cap_len > offset && tree) {
+    int			is_ppp;
+    proto_item *	ti;
+    proto_tree *	gre_tree;
+
+    if (type == GRE_PPP) {
+      is_ppp = 1;
+      ti = proto_tree_add_item(tree, offset, calc_len(flags_and_ver, 1),
+	"Generic Routing Encapsulation (PPP)");
+      gre_tree = proto_tree_new();
+      proto_item_add_subtree(ti, gre_tree, ETT_GRE);
+      add_flags_and_ver(gre_tree, flags_and_ver, offset, 1);
+    }
+    else {
+      is_ppp = 0;
+      ti = proto_tree_add_item(tree, offset, calc_len(flags_and_ver, 1),
+	"Generic Routing Encapsulation");
+      gre_tree = proto_tree_new();
+      proto_item_add_subtree(ti, gre_tree, ETT_GRE);
+      add_flags_and_ver(gre_tree, flags_and_ver, offset, 0);
+    }
+
+    offset += sizeof(flags_and_ver);
+
+    proto_tree_add_item(gre_tree, offset, sizeof(type),
+			"Protocol Type: %s (%#04x)",
+			val_to_str(type, typevals, "Unknown"), type);
+    offset += sizeof(type);    
+
+    if (flags_and_ver & GH_B_C || flags_and_ver & GH_B_R) {
+      guint16 checksum = pntohs(pd + offset);
+      proto_tree_add_item(gre_tree, offset, sizeof(checksum),
+			  "Checksum: %u", checksum);
+      offset += sizeof(checksum);
+    }
+    
+    if (flags_and_ver & GH_B_C || flags_and_ver & GH_B_R) {
+      guint16 rtoffset = pntohs(pd + offset);
+      proto_tree_add_item(gre_tree, offset, sizeof(rtoffset),
+			  "Offset: %u", rtoffset);
+      offset += sizeof(rtoffset);
+    }
+
+    if (flags_and_ver & GH_B_K) {
+      if (is_ppp) {
+	guint16	paylen;
+	guint16 callid;
+	
+	paylen = pntohs(pd + offset);
+	proto_tree_add_item(gre_tree, offset, sizeof(paylen),
+			    "Payload length: %u", paylen);
+	offset += sizeof(paylen);
+
+	callid = pntohs(pd + offset);
+	proto_tree_add_item(gre_tree, offset, sizeof(callid),
+			    "Call ID: %u", callid);
+	offset += sizeof(callid);
+      }
+      else {
+	guint32 key = pntohl(pd + offset);
+	proto_tree_add_item(gre_tree, offset, sizeof(key),
+			    "Key: %u", key);
+	offset += sizeof(key);
+      }
+    }
+    
+    if (flags_and_ver & GH_B_S) {
+      guint32 seqnum = pntohl(pd + offset);
+      proto_tree_add_item(gre_tree, offset, sizeof(seqnum),
+			  "Sequence number: %u", seqnum);
+      offset += sizeof(seqnum);
+    }
+
+    if (is_ppp && flags_and_ver & GH_P_A) {
+      guint32 acknum = pntohl(pd + offset);
+      proto_tree_add_item(gre_tree, offset, sizeof(acknum),
+			  "Acknowledgement number: %u", acknum);
+      offset += sizeof(acknum);
+    }
+
+    if (flags_and_ver & GH_B_R) {
+      proto_tree_add_item(gre_tree, offset, sizeof(guint16),
+			  "Address family: %u", pntohs(pd + offset));
+      offset += sizeof(guint16);
+      proto_tree_add_item(gre_tree, offset, 1,
+			  "SRE offset: %u", pd[offset++]);
+      proto_tree_add_item(gre_tree, offset, 1,
+			  "SRE length: %u", pd[offset++]);
+    }
+
+    switch (type) {
+       case GRE_PPP:
+ 	dissect_payload_ppp(pd, offset, fd, tree);
+ 	break;
+      default:
+	dissect_data(pd, offset, fd, gre_tree);
+    }
+  }
+}
+
+static int
+calc_len(guint16 flags_and_ver, int is_ppp) {
+  
+  int	len = 4;
+  
+  if (flags_and_ver & GH_B_C || flags_and_ver & GH_B_R) len += 4;
+  if (flags_and_ver & GH_B_K) len += 4;
+  if (flags_and_ver & GH_B_S) len += 4;
+  if (is_ppp && flags_and_ver & GH_P_A) len += 4;
+  
+  return len;
+}
+
+static void
+add_flags_and_ver(proto_tree *tree, guint16 flags_and_ver, int offset, int is_ppp) {
+
+  proto_item *	ti;
+  proto_tree *	fv_tree;
+  int		nbits = sizeof(flags_and_ver) * 8;
+  
+  ti = proto_tree_add_item(tree, offset, 2, 
+			   "Flags and version: %#08x", flags_and_ver);
+  fv_tree = proto_tree_new();
+  proto_item_add_subtree(ti, fv_tree, ETT_GRE_FLAGS);
+  
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_boolean_bitfield(flags_and_ver, GH_B_C, nbits,
+					      "Checksum", "No checksum"));
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_boolean_bitfield(flags_and_ver, GH_B_R, nbits,
+					      "Routing", "No routing"));
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_boolean_bitfield(flags_and_ver, GH_B_K, nbits,
+					      "Key", "No key"));
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_boolean_bitfield(flags_and_ver, GH_B_S, nbits,
+					      "Sequence number", "No sequence number"));
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_boolean_bitfield(flags_and_ver, GH_B_s, nbits,
+					      "Strict source route", "No strict source route"));
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_numeric_bitfield(flags_and_ver, GH_B_RECUR, nbits,
+					      "Recursion control: %u"));
+  if (is_ppp) {
+    proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+			decode_boolean_bitfield(flags_and_ver, GH_P_A, nbits,
+						"Acknowledgment number", "No acknowledgment number"));
+    proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+			decode_numeric_bitfield(flags_and_ver, GH_P_FLAGS, nbits,
+						"Flags: %u"));
+  }
+  else {
+    proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+			decode_numeric_bitfield(flags_and_ver, GH_R_FLAGS, nbits,
+						"Flags: %u"));
+  }
+
+  proto_tree_add_item(fv_tree, offset, sizeof(flags_and_ver), "%s",
+		      decode_numeric_bitfield(flags_and_ver, GH_B_VER, nbits,
+					      "Version: %u"));
+ }
+