Add COTP layer (seladb#1146)

* create COTP * create COTP tests * Add COTP to README.md * small changes * add override * add comment to cotphdr * add comment to cotp * fix type * create COTP * create COTP tests * small changes * add override * add comment to cotphdr * add comment to cotp * fix type * Changed COTP value * Renaming to camel case (in parameters, constructor, ...) * Remove unnecessary elements, modify to check the values (type, length), modify the values in tests * add explicit to constructor and override to getOsiModellLayer * Update README.md with COTP * create COTP * create COTP tests * Add COTP to README.md * small changes * add override * add comment to cotphdr * add comment to cotp * fix type * create COTP * create COTP tests * small changes * add override * add comment to cotphdr * add comment to cotp * fix type * Changed COTP value * Renaming to camel case (in parameters, constructor, ...) * Remove unnecessary elements, modify to check the values (type, length), modify the values in tests * add explicit to constructor and override to getOsiModellLayer * Update README.md with COTP * create COTP * create COTP tests * create COTP * Changed COTP value * Remove unnecessary elements, modify to check the values (type, length), modify the values in tests * add explicit to constructor and override to getOsiModellLayer * add back new lines at the end of the files * added new lines, renaming and delete unnecessary things. * remove static keyword * remove static keyword * static keyword * delete unused parameters from TpktLayer.cpp * delete unused variables * modify test * rename cotp * rename tpkt_cotp files * modify comment * modify test --------- Co-authored-by: Vörös Vivien <[email protected]>
sashashura · Jul 19, 2023 · 886dedc · 886dedc
1 parent 694c65d
commit 886dedc
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Showing 14 changed files with 262 additions and 23 deletions.
diff --git a/Packet++/CMakeLists.txt b/Packet++/CMakeLists.txt
@@ -3,6 +3,7 @@ add_library(
   $<TARGET_OBJECTS:hash-library>
   src/ArpLayer.cpp
   src/BgpLayer.cpp
+  src/CotpLayer.cpp
   src/DhcpLayer.cpp
   src/DhcpV6Layer.cpp
   src/DnsLayer.cpp
@@ -64,6 +65,7 @@ add_library(
 set(public_headers
     header/ArpLayer.h
     header/BgpLayer.h
+    header/CotpLayer.h
     header/DhcpLayer.h
     header/DhcpV6Layer.h
     header/DnsLayerEnums.h

diff --git a/Packet++/header/CotpLayer.h b/Packet++/header/CotpLayer.h
@@ -0,0 +1,120 @@
+#ifndef PCAPPLUSPLUS_COTPLAYER_H
+#define PCAPPLUSPLUS_COTPLAYER_H
+
+#include "EthLayer.h"
+#include "Layer.h"
+
+namespace pcpp
+{
+
+/**
+ * @struct cotphdr
+ * Represents a COTP protocol header
+ */
+#pragma pack(push, 1)
+	typedef struct
+	{
+		/** length */
+		uint8_t length;
+		/** PDU type identifier */
+		uint8_t pduType ;
+		/** TPDU number sequence*/
+		uint8_t tpduNumber;
+	} cotphdr;
+#pragma pack(pop)
+
+	/**
+	 * @class CotpLayer
+	 * Represents a COTP (Connection Oriented Transport Protocol)
+	 */
+	class CotpLayer : public Layer
+	{
+	  public:
+		/**
+		 * A constructor that creates the layer from an existing packet raw data
+		 * @param[in] data A pointer to the raw data (will be casted to @ref cotphdr)
+		 * @param[in] dataLen Size of the data in bytes
+		 * @param[in] prevLayer A pointer to the previous layer
+		 * @param[in] packet A pointer to the Packet instance where layer will be stored in
+		 */
+		CotpLayer(uint8_t *data, size_t dataLen, Layer *prevLayer, Packet *packet)
+			: Layer(data, dataLen, prevLayer, packet)
+		{
+			m_Protocol = COTP;
+		}
+
+		/**
+		 * A constructor that allocates a new COTP header
+		 * @param[in] tpduNumber Protocol TPDU number
+		 */
+		explicit CotpLayer(uint8_t tpduNumber);
+
+		virtual ~CotpLayer() {}
+
+		/**
+		 * @return COTP length
+		 */
+		uint8_t getLength() const;
+
+		/**
+		 * @return COTP PDU type
+		 */
+		uint8_t getPduType() const;
+
+		/**
+		 * @return COTP TPDU number
+		 */
+		uint8_t getTpduNumber() const;
+
+		/**
+		 * @return Size of @ref cotphdr
+		 */
+		size_t getHeaderLen() const override { return sizeof(cotphdr); }
+
+		/**
+		 * Set the value of the length
+		 * @param[in] length The value of the length
+		 */
+		void setLength(uint8_t length) const;
+
+		/**
+		 * Set the value of the version
+		 * @param[in] pduType The number of the PDU type
+		 */
+		void setPduType(uint8_t pduType) const;
+
+		/**
+		 * Set the value of the version
+		 * @param[in] tpduNumber The value of the TPDU number
+		 */
+		void setTpduNumber(uint8_t tpduNumber) const;
+
+		/**
+		 * Does nothing for this layer
+		 */
+		void computeCalculateFields() override {}
+
+		/**
+		 * Currently parses the rest of the packet as a generic payload (PayloadLayer)
+		 */
+		void parseNextLayer() override;
+
+		/**
+		 * A static method that takes a byte array and detects whether it is a COTP
+		 * @param[in] data A byte array
+		 * @param[in] dataSize The byte array size (in bytes)
+		 * @return True if the data looks like a valid COTP layer
+		 */
+		static bool isDataValid(const uint8_t *data, size_t dataSize);
+
+		std::string toString() const override;
+
+		OsiModelLayer getOsiModelLayer() const override { return OsiModelTransportLayer; }
+
+	  private:
+		cotphdr *getCotpHeader() const { return (cotphdr *)m_Data; }
+	};
+
+} // namespace pcpp
+
+#endif // PCAPPLUSPLUS_COTPLAYER_H
diff --git a/Packet++/header/ProtocolType.h b/Packet++/header/ProtocolType.h
@@ -317,6 +317,11 @@ namespace pcpp
 	 */
 	const ProtocolType VRRPv3 = 0x2000000000000;
 
+	/**
+	 * COTP protocol
+	 */
+	const ProtocolType COTP = 0x900000000000;
+
 	/**
 	 * An enum representing OSI model layers
 	 */

diff --git a/Packet++/header/TpktLayer.h b/Packet++/header/TpktLayer.h
@@ -96,7 +96,7 @@ namespace pcpp
 		void computeCalculateFields() override {}
 
 		/**
-		 * Currently parses the rest of the packet as a generic payload (PayloadLayer)
+		 * Currently parses the rest of the packet as a COTP protocol or generic payload (PayloadLayer)
 		 */
 		void parseNextLayer() override;
 

diff --git a/Packet++/src/CotpLayer.cpp b/Packet++/src/CotpLayer.cpp
@@ -0,0 +1,60 @@
+#include "../header/CotpLayer.h"
+#include "EndianPortable.h"
+#include <PayloadLayer.h>
+#include <cstring>
+#include <iostream>
+#include <sstream>
+
+namespace pcpp
+{
+
+	pcpp::CotpLayer::CotpLayer(uint8_t tpduNumber)
+	{
+		const size_t headerLen = sizeof(cotphdr);
+		m_DataLen = headerLen;
+		m_Data = new uint8_t[headerLen];
+		memset(m_Data, 0, headerLen);
+		cotphdr *cotpHdr = (cotphdr *)m_Data;
+		cotpHdr->length = 0x02;
+		cotpHdr->pduType = 0x0f;
+		cotpHdr->tpduNumber = tpduNumber;
+		m_Protocol = COTP;
+	}
+
+	std::string CotpLayer::toString() const
+	{
+		return "Cotp Layer";
+	}
+
+	uint8_t CotpLayer::getLength() const { return getCotpHeader()->length; }
+
+	uint8_t CotpLayer::getPduType() const { return getCotpHeader()->pduType; }
+
+	uint8_t CotpLayer::getTpduNumber() const { return getCotpHeader()->tpduNumber; }
+
+	void CotpLayer::setLength(uint8_t length) const { getCotpHeader()->length = length; }
+
+	void CotpLayer::setPduType(uint8_t pduType) const { getCotpHeader()->pduType = pduType; }
+
+	void CotpLayer::setTpduNumber(uint8_t tpduNumber) const { getCotpHeader()->tpduNumber = tpduNumber; }
+
+	bool CotpLayer::isDataValid(const uint8_t *data, size_t dataSize)
+	{
+		if (!data || dataSize < sizeof(cotphdr))
+			return false;
+
+		return  data[1] == 0xf0 && data[0] == 2;
+	}
+
+	void CotpLayer::parseNextLayer()
+	{
+		size_t headerLen = getHeaderLen();
+		if (m_DataLen <= headerLen)
+			return;
+
+		uint8_t *payload = m_Data + headerLen;
+		size_t payloadLen = m_DataLen - headerLen;
+
+		m_NextLayer = new PayloadLayer(payload, payloadLen, this, m_Packet);
+	}
+} // namespace pcpp
diff --git a/Packet++/src/TpktLayer.cpp b/Packet++/src/TpktLayer.cpp
@@ -1,6 +1,7 @@
 #include "TpktLayer.h"
 #include "EndianPortable.h"
 #include "TcpLayer.h"
+#include "CotpLayer.h"
 #include "PayloadLayer.h"
 #include <iostream>
 #include <sstream>
@@ -48,7 +49,11 @@ namespace pcpp
 
 		uint8_t *payload = m_Data + headerLen;
 		size_t payloadLen = m_DataLen - headerLen;
-		m_NextLayer = new PayloadLayer(payload, payloadLen, this, m_Packet);
+
+		if (CotpLayer::isDataValid(payload, payloadLen)) {
+			m_NextLayer = new CotpLayer(payload, payloadLen, this, m_Packet);
+		} else
+			m_NextLayer = new PayloadLayer(payload, payloadLen, this, m_Packet);
 	}
 
 } // namespace pcpp
diff --git a/README.md b/README.md
@@ -230,35 +230,36 @@ PcapPlusPlus currently supports parsing, editing and creation of packets of the
 
 ### Transport Layer (L4)
 
-24. GTP (v1)
-25. IPSec AH & ESP - parsing only (no editing capabilities)
-26. TCP
-27. TPKT
-28. UDP
+24. COTP
+25. GTP (v1)
+26. IPSec AH & ESP - parsing only (no editing capabilities)
+27. TCP
+28. TPKT
+29. UDP
 
 ### Session Layer (L5)
 
-29. SDP
-30. SIP
+30. SDP
+31. SIP
 
 ### Presentation Layer (L6)
 
-31. SSL/TLS - parsing only (no editing capabilities)
+32. SSL/TLS - parsing only (no editing capabilities)
 
 ### Application Layer (L7)
 
-32. BGP (v4)
-33. DHCP
-34. DHCPv6
-35. DNS
-36. FTP
-37. HTTP headers (request & response)
-38. NTP (v3, v4)
-39. Radius
-40. SOME/IP
-41. SSH - parsing only (no editing capabilities)
-42. Telnet - parsing only (no editing capabilities)
-43. Generic payload
+33.  BGP (v4)
+34. DHCP
+35. DHCPv6
+36. DNS
+37. FTP
+38. HTTP headers (request & response)
+39. NTP (v3, v4)
+40. Radius
+41. SOME/IP
+42. SSH - parsing only (no editing capabilities)
+43. Telnet - parsing only (no editing capabilities)
+44. Generic payload
 
 ## DPDK And PF_RING Support
 

diff --git a/Tests/Packet++Test/CMakeLists.txt b/Tests/Packet++Test/CMakeLists.txt
@@ -2,6 +2,7 @@ add_executable(
   Packet++Test
   main.cpp
   Tests/BgpTests.cpp
+  Tests/CotpTests.cpp
   Tests/DhcpTests.cpp
   Tests/DhcpV6Tests.cpp
   Tests/DnsTests.cpp

diff --git a/Tests/Packet++Test/PacketExamples/tpkt.dat → ...Packet++Test/PacketExamples/tpkt_cotp.dat b/Tests/Packet++Test/PacketExamples/tpkt.dat → ...Packet++Test/PacketExamples/tpkt_cotp.dat
diff --git a/Tests/Packet++Test/PacketExamples/cotp.pcap → ...acket++Test/PacketExamples/tpkt_cotp.pcap b/Tests/Packet++Test/PacketExamples/cotp.pcap → ...acket++Test/PacketExamples/tpkt_cotp.pcap
diff --git a/Tests/Packet++Test/TestDefinition.h b/Tests/Packet++Test/TestDefinition.h
@@ -235,3 +235,6 @@ PTF_TEST_CASE(TpktLayerTest);
 // Implemented in VrrpTests.cpp
 PTF_TEST_CASE(VrrpParsingTest);
 PTF_TEST_CASE(VrrpCreateAndEditTest);
+
+//Implemented in CotpTests.cpp
+PTF_TEST_CASE(CotpLayerTest);
diff --git a/Tests/Packet++Test/Tests/CotpTests.cpp b/Tests/Packet++Test/Tests/CotpTests.cpp
@@ -0,0 +1,40 @@
+#include "../TestDefinition.h"
+#include "../Utils/TestUtils.h"
+#include "CotpLayer.h"
+#include "Packet.h"
+#include "SystemUtils.h"
+
+using namespace std;
+
+PTF_TEST_CASE(CotpLayerTest)
+{
+	timeval time;
+	gettimeofday(&time, nullptr);
+
+	READ_FILE_AND_CREATE_PACKET(1, "PacketExamples/tpkt_cotp.dat");
+
+	pcpp::Packet cotpPacket(&rawPacket1);
+	PTF_ASSERT_TRUE(cotpPacket.isPacketOfType(pcpp::COTP));
+	auto cotpLayer = cotpPacket.getLayerOfType<pcpp::CotpLayer>();
+	PTF_ASSERT_NOT_NULL(cotpLayer);
+	PTF_ASSERT_EQUAL(cotpLayer->getNextLayer()->getProtocol(), pcpp::GenericPayload, enum);
+	PTF_ASSERT_EQUAL(cotpLayer->getHeaderLen(), 3);
+	PTF_ASSERT_EQUAL(cotpLayer->getLength(), 0x02);
+	PTF_ASSERT_EQUAL(cotpLayer->getPduType(), 0xf0);
+	PTF_ASSERT_EQUAL(cotpLayer->getTpduNumber(), 0x80);
+	PTF_ASSERT_EQUAL(cotpLayer->toString(), "Cotp Layer");
+
+	pcpp::CotpLayer newCotpPacket(120);
+	PTF_ASSERT_EQUAL(newCotpPacket.getHeaderLen(), 3);
+	PTF_ASSERT_EQUAL(newCotpPacket.getLength(), 0x02);
+	PTF_ASSERT_EQUAL(newCotpPacket.getPduType(), 0x0f);
+	PTF_ASSERT_EQUAL(newCotpPacket.getTpduNumber(), 0x78);
+
+	newCotpPacket.setLength((uint8_t)4);
+	newCotpPacket.setPduType((uint8_t)210);
+	newCotpPacket.setTpduNumber((uint8_t)125);
+	PTF_ASSERT_EQUAL(newCotpPacket.getLength(), 0x04);
+	PTF_ASSERT_EQUAL(newCotpPacket.getPduType(), 0xd2);
+	PTF_ASSERT_EQUAL(newCotpPacket.getTpduNumber(), 0x7d);
+
+} // CotpLayerTest
diff --git a/Tests/Packet++Test/Tests/TpktTests.cpp b/Tests/Packet++Test/Tests/TpktTests.cpp
@@ -11,7 +11,7 @@ PTF_TEST_CASE(TpktLayerTest)
 	timeval time;
 	gettimeofday(&time, nullptr);
 
-	READ_FILE_AND_CREATE_PACKET(1, "PacketExamples/tpkt.dat");
+	READ_FILE_AND_CREATE_PACKET(1, "PacketExamples/tpkt_cotp.dat");
 
 	pcpp::Packet TpktPacketNoOptions(&rawPacket1);
 	PTF_ASSERT_TRUE(TpktPacketNoOptions.isPacketOfType(pcpp::TPKT));

diff --git a/Tests/Packet++Test/main.cpp b/Tests/Packet++Test/main.cpp
@@ -309,5 +309,7 @@ int main(int argc, char* argv[])
 	PTF_RUN_TEST(VrrpParsingTest, "vrrp");
 	PTF_RUN_TEST(VrrpCreateAndEditTest, "vrrp");
 
+	PTF_RUN_TEST(CotpLayerTest, "cotp");
+
 	PTF_END_RUNNING_TESTS;
 }