Give the user the ability to decide how to decode USER DLTs

git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@14551 f5534014-38df-0310-8fa8-9805f1628bb7

1 files changed, 210 insertions, 0 deletions

diff --git a/epan/dissectors/packet-user_encap.c b/epan/dissectors/packet-user_encap.c
new file mode 100644
index 0000000000..79c474f570
--- /dev/null
+++ b/epan/dissectors/packet-user_encap.c
@@ -0,0 +1,210 @@
+/* packet-user_encap.c
+ * Allow users to specify the dissectors for USERn DLTs
+ * Luis E. Garcia Ontanon <luis.ontanon@gmail.com>
+ *
+ * $Id$
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@ethereal.com>
+ * Copyright 1998
+ *
+ *
+ * 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
+
+#include <glib.h>
+#include <epan/packet.h>
+#include <epan/prefs.h>
+#include <epan/report_err.h>
+
+#include <epan/dissectors/packet-sscop.h>
+
+typedef void (*encap_dissector_t)(tvbuff_t*,packet_info*,proto_tree*,dissector_handle_t);
+
+typedef struct _user_encap_t {
+	gchar* name;
+	gchar* abbr;
+	gchar* long_name;
+	
+	gchar* payload;
+	gchar* header;
+	gchar* trailer;
+	guint header_size;
+	guint trailer_size;
+	
+	int hfid;
+	
+	gint encap;
+	
+	encap_dissector_t encap_dissector;
+	dissector_t dissector;
+	
+	module_t* module;
+	
+	dissector_handle_t handle;
+	dissector_handle_t payload_handle;
+	dissector_handle_t header_handle;
+	dissector_handle_t trailer_handle;
+} user_encap_t;
+
+static const enum_val_t encap_types[] = {
+	{ "None", "No encpsulation", 0 },
+	{ "SSCOP" , "SSCOP", 1 },
+	{ NULL, NULL, 0 }
+};
+
+static const encap_dissector_t encap_dissectors[] = {
+	NULL,
+	dissect_sscop_and_payload
+};
+
+static void dissect_user(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree,guint id);
+
+static void dissect_user0(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,0); } 
+static void dissect_user1(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,1); } 
+static void dissect_user2(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,2); } 
+static void dissect_user3(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,3); } 
+static void dissect_user4(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,4); } 
+static void dissect_user5(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,5); } 
+static void dissect_user6(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,6); } 
+static void dissect_user7(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,7); } 
+static void dissect_user8(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,8); } 
+static void dissect_user9(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,9); } 
+static void dissect_user10(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,10); } 
+static void dissect_user11(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,11); } 
+static void dissect_user12(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,12); } 
+static void dissect_user13(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,13); } 
+static void dissect_user14(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,14); } 
+static void dissect_user15(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree) { dissect_user(tvb,pinfo,tree,15); } 
+
+user_encap_t encaps[] = {
+	{"USER0","user0","DLT_USER00","","","",0,0,-1,0,NULL,dissect_user0,NULL,NULL,NULL,NULL,NULL},
+	{"USER1","user1","DLT_USER01","","","",0,0,-1,0,NULL,dissect_user1,NULL,NULL,NULL,NULL,NULL},
+	{"USER2","user2","DLT_USER02","","","",0,0,-1,0,NULL,dissect_user2,NULL,NULL,NULL,NULL,NULL},
+	{"USER3","user3","DLT_USER03","","","",0,0,-1,0,NULL,dissect_user3,NULL,NULL,NULL,NULL,NULL},
+	{"USER4","user4","DLT_USER04","","","",0,0,-1,0,NULL,dissect_user4,NULL,NULL,NULL,NULL,NULL},
+	{"USER5","user5","DLT_USER05","","","",0,0,-1,0,NULL,dissect_user5,NULL,NULL,NULL,NULL,NULL},
+	{"USER6","user6","DLT_USER06","","","",0,0,-1,0,NULL,dissect_user6,NULL,NULL,NULL,NULL,NULL},
+	{"USER7","user7","DLT_USER07","","","",0,0,-1,0,NULL,dissect_user7,NULL,NULL,NULL,NULL,NULL},
+	{"USER8","user8","DLT_USER08","","","",0,0,-1,0,NULL,dissect_user8,NULL,NULL,NULL,NULL,NULL},
+	{"USER9","user9","DLT_USER09","","","",0,0,-1,0,NULL,dissect_user9,NULL,NULL,NULL,NULL,NULL},
+	{"USER10","user10","DLT_USER10","","","",0,0,-1,0,NULL,dissect_user10,NULL,NULL,NULL,NULL,NULL},
+	{"USER11","user11","DLT_USER11","","","",0,0,-1,0,NULL,dissect_user11,NULL,NULL,NULL,NULL,NULL},
+	{"USER12","user12","DLT_USER12","","","",0,0,-1,0,NULL,dissect_user12,NULL,NULL,NULL,NULL,NULL},
+	{"USER13","user13","DLT_USER13","","","",0,0,-1,0,NULL,dissect_user13,NULL,NULL,NULL,NULL,NULL},
+	{"USER14","user14","DLT_USER14","","","",0,0,-1,0,NULL,dissect_user14,NULL,NULL,NULL,NULL,NULL},
+	{"USER15","user15","DLT_USER15","","","",0,0,-1,0,NULL,dissect_user15,NULL,NULL,NULL,NULL,NULL},
+};
+
+static void dissect_user(tvbuff_t* tvb,packet_info* pinfo,proto_tree* tree,guint id) {
+	user_encap_t* encap = &(encaps[id]);
+	tvbuff_t* payload_tvb;
+	int offset = 0;
+	int len = tvb_reported_length(tvb) - (encap->header_size + encap->trailer_size);
+	
+	if (encap->encap_dissector) {
+		encap->encap_dissector(tvb,pinfo,tree,encap->payload_handle);
+		return;
+	}
+	
+	if (encap->header_size) {
+		tvbuff_t* hdr_tvb = tvb_new_subset(tvb, 0, encap->header_size, encap->header_size);
+		call_dissector(encap->header_handle, hdr_tvb, pinfo, tree);
+		offset = encap->header_size;
+	}
+	
+	payload_tvb = tvb_new_subset(tvb, encap->header_size, len, len);
+	call_dissector(encap->payload_handle, payload_tvb, pinfo, tree);
+
+	if (encap->trailer_size) {
+		tvbuff_t* trailer_tvb = tvb_new_subset(tvb, 0, encap->trailer_size, encap->trailer_size);
+		call_dissector(encap->trailer_handle, trailer_tvb, pinfo, tree);
+		offset = encap->trailer_size;
+	}
+}
+
+void proto_reg_handoff_user_encap(void)
+{
+	int i = 0;
+	static dissector_handle_t data_handle;
+	
+	data_handle = find_dissector("data");
+
+	do {
+		encaps[i].handle =  find_dissector(encaps[i].abbr);
+		dissector_add("wtap_encap", WTAP_ENCAP_USER0 + i, encaps[i].handle);
+
+		if(*(encaps[i].payload) != '\0') {
+			encaps[i].payload_handle = find_dissector(encaps[i].payload);
+			
+			if (encaps[i].payload_handle == NULL) {
+				encaps[i].payload_handle = data_handle;
+				report_failure("%s: No such proto: %s",encaps[i].long_name,encaps[i].payload);
+			}
+		} else {
+			encaps[i].payload_handle = data_handle;			
+		}
+
+		if(*(encaps[i].header) != '\0') {
+			encaps[i].header_handle = find_dissector(encaps[i].header);
+			
+			if (encaps[i].header_handle == NULL) {
+				encaps[i].header_handle = data_handle;
+				report_failure("%s: No such proto: %s",encaps[i].long_name,encaps[i].header);
+			}
+		} else {
+			encaps[i].header_handle = data_handle;			
+		}
+		
+		if(*(encaps[i].trailer) != '\0') {
+			encaps[i].trailer_handle = find_dissector(encaps[i].trailer);
+			
+			if (encaps[i].trailer_handle == NULL) {
+				encaps[i].trailer_handle = data_handle;
+				report_failure("%s: No such proto: %s",encaps[i].long_name,encaps[i].trailer);
+			}
+		} else {
+			encaps[i].trailer_handle = data_handle;			
+		}
+		
+		encaps[i].encap_dissector = encap_dissectors[encaps[i].encap];
+		
+		i++;
+	} while(i<16);
+	
+}
+
+void proto_register_user_encap(void)
+{
+	int i;
+	
+	for (i = 0; i < 16; i++) {
+		encaps[i].hfid = proto_register_protocol(encaps[i].name, encaps[i].long_name, encaps[i].abbr);
+		encaps[i].module = prefs_register_protocol(encaps[i].hfid, proto_reg_handoff_user_encap);
+		
+		prefs_register_string_preference(encaps[i].module, "payload","Payload", "Payload", &encaps[i].payload);
+		prefs_register_enum_preference(encaps[i].module, "encap","Encapsulation", "The encapsulation used", &encaps[i].encap, encap_types, FALSE);
+		prefs_register_uint_preference(encaps[i].module, "header_size","Header Size", "The size (in bytes) of the Header (0 if none)", 10, &encaps[i].header_size);
+		prefs_register_uint_preference(encaps[i].module, "trailer_size","Trailer Size", "The size (in bytes) of the Trailer (0 if none)", 10, &encaps[i].trailer_size);
+		prefs_register_string_preference(encaps[i].module, "header_proto","Header Protocol", "Header Protocol (used only when ecapsulation is not given)", &encaps[i].header);
+		prefs_register_string_preference(encaps[i].module, "trailer_proto","Trailer Protocol", "Trailer Protocol (used only when ecapsulation is not given)", &encaps[i].trailer);
+		
+		register_dissector(encaps[i].abbr, encaps[i].dissector, encaps[i].hfid);
+	}
+}