Kerberos - Add TCP support

scripts/base/protocols/krb/main.bro

@@ -71,12 +71,14 @@ redef record connection += {
 	krb: Info &optional;
 };
 
-const ports = { 88/udp };
+const udp_ports = { 88/udp, 750/udp };
+const tcp_ports = { 88/tcp, 750/tcp };
 
 event bro_init() &priority=5
 	{
 	Log::create_stream(KRB::LOG, [$columns=Info, $ev=log_krb]);
-	Analyzer::register_for_ports(Analyzer::ANALYZER_KRB, ports);
+	Analyzer::register_for_ports(Analyzer::ANALYZER_KRB, udp_ports);
+	Analyzer::register_for_ports(Analyzer::ANALYZER_KRB_TCP, tcp_ports);
 	}
 
 event krb_error(c: connection, msg: Error_Msg)

src/analyzer/protocol/krb/CMakeLists.txt

@@ -1,4 +1,3 @@
-
 include(BroPlugin)
 
 include_directories(BEFORE ${CMAKE_CURRENT_SOURCE_DIR}
@@ -10,3 +9,8 @@ bro_plugin_bif(types.bif)
 bro_plugin_bif(events.bif)
 bro_plugin_pac(krb.pac krb-protocol.pac krb-analyzer.pac)
 bro_plugin_end()
+
+bro_plugin_begin(Bro KRB_TCP)
+bro_plugin_cc(KRB_TCP.cc Plugin_TCP.cc)
+bro_plugin_pac(krb_TCP.pac krb-protocol.pac krb-analyzer.pac)
+bro_plugin_end()

src/analyzer/protocol/krb/KRB_TCP.cc

@@ -0,0 +1,66 @@
+// See the file "COPYING" in the main distribution directory for copyright.
+
+#include "KRB_TCP.h"
+#include "analyzer/protocol/tcp/TCP_Reassembler.h"
+#include "types.bif.h"
+#include "events.bif.h"
+
+using namespace analyzer::krb_tcp;
+
+KRB_Analyzer::KRB_Analyzer(Connection* conn)
+	: tcp::TCP_ApplicationAnalyzer("KRB_TCP", conn)
+	{
+	interp = new binpac::KRB_TCP::KRB_Conn(this);
+	had_gap = false;
+	}
+
+KRB_Analyzer::~KRB_Analyzer()
+	{
+	delete interp;
+	}
+
+void KRB_Analyzer::Done()
+	{
+	tcp::TCP_ApplicationAnalyzer::Done();
+
+	interp->FlowEOF(true);
+	interp->FlowEOF(false);
+	}
+
+void KRB_Analyzer::EndpointEOF(bool is_orig)
+	{
+	tcp::TCP_ApplicationAnalyzer::EndpointEOF(is_orig);
+	interp->FlowEOF(is_orig);
+	}
+
+void KRB_Analyzer::DeliverStream(int len, const u_char* data, bool orig)
+	{
+	tcp::TCP_ApplicationAnalyzer::DeliverStream(len, data, orig);
+
+	assert(TCP());
+	if ( TCP()->IsPartial() )
+		return;
+
+	if ( had_gap )
+		// If only one side had a content gap, we could still try to
+		// deliver data to the other side if the script layer can
+		// handle this.
+		return;
+
+	try
+		{
+		interp->NewData(orig, data, data + len);
+		}
+	catch ( const binpac::Exception& e )
+		{
+		printf("BinPAC Exception: %s\n", e.c_msg());
+		ProtocolViolation(e.c_msg());
+		}
+	}
+
+void KRB_Analyzer::Undelivered(uint64 seq, int len, bool orig)
+	{
+	tcp::TCP_ApplicationAnalyzer::Undelivered(seq, len, orig);
+	had_gap = true;
+	interp->NewGap(orig, len);
+	}

src/analyzer/protocol/krb/KRB_TCP.h

@@ -0,0 +1,37 @@
+// See the file "COPYING" in the main distribution directory for copyright.
+
+#ifndef ANALYZER_PROTOCOL_KRB_KRB_TCP_H
+#define ANALYZER_PROTOCOL_KRB_KRB_TCP_H
+
+#include "analyzer/protocol/tcp/TCP.h"
+
+#include "krb_TCP_pac.h"
+
+namespace analyzer { namespace krb_tcp {
+
+class KRB_Analyzer : public tcp::TCP_ApplicationAnalyzer {
+
+public:
+
+	KRB_Analyzer(Connection* conn);
+	virtual ~KRB_Analyzer();
+
+	virtual void Done();
+	virtual void DeliverStream(int len, const u_char* data, bool orig);
+	virtual void Undelivered(uint64 seq, int len, bool orig);
+
+	// Overriden from tcp::TCP_ApplicationAnalyzer.
+	virtual void EndpointEOF(bool is_orig);
+
+	static analyzer::Analyzer* Instantiate(Connection* conn)
+		{ return new KRB_Analyzer(conn); }
+
+protected:
+	
+	binpac::KRB_TCP::KRB_Conn* interp;
+	bool had_gap;
+};
+
+} } // namespace analyzer::* 
+
+#endif

src/analyzer/protocol/krb/Plugin_TCP.cc

@@ -0,0 +1,20 @@
+//See the file in the main distribution directory for copyright.
+
+#include "plugin/Plugin.h"
+#include "KRB_TCP.h"
+
+namespace plugin {
+	namespace Bro_KRB_TCP {
+		class Plugin : public plugin::Plugin {
+		public:
+			plugin::Configuration Configure()
+				{
+				AddComponent(new ::analyzer::Component("KRB_TCP", ::analyzer::krb_tcp::KRB_Analyzer::Instantiate));
+				plugin::Configuration config;
+				config.name = "Bro::KRB_TCP";
+				config.description = "Kerberos analyzer (TCP)";
+				return config;
+				}
+		} plugin;
+	}
+}

src/analyzer/protocol/krb/krb-analyzer.pac

@@ -1,12 +1,3 @@
-connection KRB_Conn(bro_analyzer: BroAnalyzer) {
-	upflow = KRB_Flow(true);
-	downflow = KRB_Flow(false);
-};
-
-flow KRB_Flow(is_orig: bool) {
-	datagram = KRB_PDU withcontext(connection, this);
-};
-
 %header{
 Val* GetTimeFromAsn1(const KRB_Time* atime);
 Val* GetTimeFromAsn1(StringVal* atime);
@@ -111,6 +102,7 @@ refine connection KRB_Conn += {
 
 	function proc_krb_kdc_req(msg: KRB_KDC_REQ): bool
 		%{
+		bro_analyzer()->ProtocolConfirmation();
 		if ( ( binary_to_int64(${msg.msg_type.data.content}) == 10 ) && ! krb_as_req )
 			return false;
 
@@ -266,6 +258,7 @@ refine connection KRB_Conn += {
 
  	function proc_krb_kdc_rep(msg: KRB_KDC_REP): bool
 		%{
+		bro_analyzer()->ProtocolConfirmation();
 		
 		if ( ( binary_to_int64(${msg.msg_type.data.content}) == 11 ) && ! krb_as_rep )
 			return false;
@@ -337,18 +330,21 @@ refine connection KRB_Conn += {
     
  	function proc_krb_ap_req(msg: KRB_AP_REQ): bool
 		%{
-			// Not implemented
+		bro_analyzer()->ProtocolConfirmation();
-    		return true;
+		// Not implemented
+   		return true;
    		%}
     
  	function proc_krb_ap_rep(msg: KRB_AP_REP): bool
 		%{
-			// Not implemented
+		bro_analyzer()->ProtocolConfirmation();
-    		return true;
+		// Not implemented
+   		return true;
    		%}
     
  	function proc_krb_error_msg(msg: KRB_ERROR_MSG): bool
 		%{
+		bro_analyzer()->ProtocolConfirmation();
 		if ( krb_error )
 			{
 			RecordVal* rv = new RecordVal(BifType::Record::KRB::Error_Msg);
@@ -431,20 +427,23 @@ refine connection KRB_Conn += {
     
  	function proc_krb_safe_msg(msg: KRB_SAFE_MSG): bool
 		%{
-			// Not implemented
+		bro_analyzer()->ProtocolConfirmation();
-    		return true;
+		// Not implemented
+   		return true;
    		%}
     
  	function proc_krb_priv_msg(msg: KRB_PRIV_MSG): bool
 		%{	
-			// Not implemented
+		bro_analyzer()->ProtocolConfirmation();
-    		return true;
+		// Not implemented
+   		return true;
    		%}
     
  	function proc_krb_cred_msg(msg: KRB_CRED_MSG): bool
 		%{
-			// Not implemented
+		bro_analyzer()->ProtocolConfirmation();
-    		return true;
+		// Not implemented
+   		return true;
    		%}
 
 	function debug_req_arg(msg: KRB_REQ_Arg_Data): bool

src/analyzer/protocol/krb/krb-protocol.pac

@@ -13,6 +13,11 @@ enum KRBMessageTypes {
 	KRB_ERROR = 30,
 };
 
+type KRB_PDU_TCP = record {
+	size: uint32;
+	pdu	: KRB_PDU;
+} &length=size+4 &byteorder=bigendian;
+
 type KRB_PDU = record {
 	app_meta  : ASN1EncodingMeta;
 	msg_type  : case (app_meta.tag - 96) of {

src/analyzer/protocol/krb/krb.pac

@@ -11,5 +11,15 @@ analyzer KRB withcontext {
 	flow:		KRB_Flow;
 };
 
+connection KRB_Conn(bro_analyzer: BroAnalyzer) {
+	upflow = KRB_Flow(true);
+	downflow = KRB_Flow(false);
+};
+
 %include krb-protocol.pac
+
+flow KRB_Flow(is_orig: bool) {
+	datagram = KRB_PDU withcontext(connection, this);
+};
+
 %include krb-analyzer.pac

src/analyzer/protocol/krb/krb_TCP.pac

@@ -0,0 +1,25 @@
+%include binpac.pac
+%include bro.pac
+
+%extern{
+#include "types.bif.h"
+#include "events.bif.h"
+%}
+
+analyzer KRB_TCP withcontext {
+	connection:	KRB_Conn;
+	flow:		KRB_Flow;
+};
+
+connection KRB_Conn(bro_analyzer: BroAnalyzer) {
+	upflow = KRB_Flow(true);
+	downflow = KRB_Flow(false);
+};
+
+%include krb-protocol.pac
+
+flow KRB_Flow(is_orig: bool) {
+	flowunit = KRB_PDU_TCP withcontext(connection, this);
+};
+
+%include krb-analyzer.pac