Fix getParameter()

seladb · Oct 3, 2023 · 6502dcb · 6502dcb
1 parent 9ffc140
commit 6502dcb
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Showing 3 changed files with 24 additions and 12 deletions.
diff --git a/Packet++/header/S7commLayer.h b/Packet++/header/S7commLayer.h
@@ -47,7 +47,7 @@ namespace pcpp
 
 	  public:
 		S7CommParameter() {}
-		uint8_t *getData() { return m_Data; }
+		uint8_t *getData() const { return m_Data; }
 		size_t getDataLength() const { return m_DataLen; }
 
 	  private:
@@ -126,7 +126,7 @@ namespace pcpp
 		 */
 		uint8_t getErrorClass() const;
 
-		S7CommParameter *getParameter() const;
+		const S7CommParameter *getParameter();
 
 		/**
 		 * Set the value of the message type
@@ -207,6 +207,9 @@ namespace pcpp
 			}
 			return nullptr;
 		}
+
+		size_t getS7commHeaderLength() const;
+
 		S7CommParameter* m_Parameter;
 	};
 

diff --git a/Packet++/src/S7commLayer.cpp b/Packet++/src/S7commLayer.cpp
@@ -102,16 +102,24 @@ namespace pcpp
 
 	void S7commLayer::setErrorClass(uint8_t error_class) const { getS7commAckDataHeader()->error_class = error_class; }
 
-	S7CommParameter *S7commLayer::getParameter() const
+	const S7CommParameter *S7commLayer::getParameter()
 	{
-		S7CommParameter *m_Parameter = nullptr;
-
-		uint8_t *payload = m_Data + getHeaderLen() - getParamLength() -getDataLen();//- getHeaderLen() + parameterLen; //;+ parameterLen;
-		size_t payloadLen = m_DataLen - getHeaderLen() + getParamLength() + getDataLength();
-
-		m_Parameter = new S7CommParameter(payload, payloadLen);
+		if (!m_Parameter)
+		{
+			uint8_t *payload = m_Data + getS7commHeaderLength();
+			m_Parameter = new S7CommParameter(payload, getParamLength());
+		}
 
 		return m_Parameter;
 	}
 
+	size_t S7commLayer::getS7commHeaderLength() const
+	{
+		if (getS7commHeader()->msg_type == 0x03)
+		{
+			return sizeof(s7comm_ack_data_hdr);
+		}
+		return sizeof(s7commhdr);
+	}
+
 } // namespace pcpp
diff --git a/Tests/Packet++Test/Tests/S7commTests.cpp b/Tests/Packet++Test/Tests/S7commTests.cpp
@@ -4,7 +4,6 @@
 #include "Packet.h"
 #include "S7commLayer.h"
 #include "SystemUtils.h"
-#include <stdio.h>
 
 PTF_TEST_CASE(S7commLayerTest)
 {
@@ -26,8 +25,10 @@ PTF_TEST_CASE(S7commLayerTest)
 	PTF_ASSERT_EQUAL(s7commLayer->getHeaderLen(), 0xea);
 	PTF_ASSERT_EQUAL(s7commLayer->toString(),
 					 "S7comm Layer, msg_type: 7, pdu_ref: 64779, param_length: 12, data_length: 212");
-	std::cout << (s7commLayer->getParameter()->getDataLength()) << std::endl;
-	std::cout << (s7commLayer->getParameter()->getData()) << std::endl;
+
+	PTF_ASSERT_EQUAL(s7commLayer->getParameter()->getDataLength(), 12);
+	uint8_t expectedParameterData[] = { 0x00, 0x01, 0x12, 0x08, 0x12, 0x84, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00 };
+	PTF_ASSERT_BUF_COMPARE(s7commLayer->getParameter()->getData(), expectedParameterData, 12);
 
 	pcpp::S7commLayer newS7commPacket(0x09, 0xfd0c, 13, 213);