From 3b68a3ed1da6968d6123adc5c1140d4c96d1c5f3 Mon Sep 17 00:00:00 2001
From: Jakob Meier <meier-jakob@gmx.de>
Date: Fri, 15 Nov 2024 10:11:19 +0100
Subject: [PATCH] added optional crc check to space packet parsing

---
 src/fsfw/tmtcservices/SpacePacketParser.cpp | 10 ++++++++++
 src/fsfw/tmtcservices/SpacePacketParser.h   |  8 ++++++++
 2 files changed, 18 insertions(+)

diff --git a/src/fsfw/tmtcservices/SpacePacketParser.cpp b/src/fsfw/tmtcservices/SpacePacketParser.cpp
index 75db7a4e..440a988e 100644
--- a/src/fsfw/tmtcservices/SpacePacketParser.cpp
+++ b/src/fsfw/tmtcservices/SpacePacketParser.cpp
@@ -1,11 +1,16 @@
 #include <fsfw/serviceinterface/ServiceInterface.h>
 #include <fsfw/tmtcservices/SpacePacketParser.h>
+#include <fsfw/globalfunctions/CRC.h>
 
 #include <algorithm>
 
 SpacePacketParser::SpacePacketParser(std::vector<uint16_t> validPacketIds)
     : validPacketIds(validPacketIds) {}
 
+void SpacePacketParser::enableCrcCheck() {
+	checkCrc = true;
+}
+
 ReturnValue_t SpacePacketParser::parseSpacePackets(const uint8_t** buffer, const size_t maxSize,
                                                    FoundPacketInfo& packetInfo) {
   if (buffer == nullptr or nextStartIdx > maxSize) {
@@ -31,6 +36,11 @@ ReturnValue_t SpacePacketParser::parseSpacePackets(const uint8_t** buffer, const
     }
     *buffer += packetInfo.sizeFound;
     packetInfo.startIdx = localIdx + amountRead;
+    if (checkCrc) {
+    	if (CRC::crc16ccitt(bufPtr + localIdx, packetSize) != 0) {
+				return CRC_CHECK_FAILED;
+			}
+    }
     nextStartIdx = localIdx + amountRead + packetInfo.sizeFound;
     amountRead = nextStartIdx;
     return result;
diff --git a/src/fsfw/tmtcservices/SpacePacketParser.h b/src/fsfw/tmtcservices/SpacePacketParser.h
index ea0a2feb..ea780bed 100644
--- a/src/fsfw/tmtcservices/SpacePacketParser.h
+++ b/src/fsfw/tmtcservices/SpacePacketParser.h
@@ -25,6 +25,13 @@ class SpacePacketParser {
   static constexpr uint8_t INTERFACE_ID = CLASS_ID::SPACE_PACKET_PARSER;
   static constexpr ReturnValue_t NO_PACKET_FOUND = MAKE_RETURN_CODE(0x00);
   static constexpr ReturnValue_t SPLIT_PACKET = MAKE_RETURN_CODE(0x01);
+  static constexpr ReturnValue_t CRC_CHECK_FAILED = MAKE_RETURN_CODE(0x02);
+
+  /**
+   * brief If the last to bytes of a space packet hold a CRC16, this function can be used to enable
+   * 			 the CRC16 check when parsing the data.
+   */
+  void enableCrcCheck();
 
   /**
    * @brief   Parser constructor.
@@ -61,6 +68,7 @@ class SpacePacketParser {
   std::vector<uint16_t> validPacketIds;
   size_t nextStartIdx = 0;
   size_t amountRead = 0;
+  bool checkCrc = false;
 };
 
 #endif /* FRAMEWORK_TMTCSERVICES_PUSPARSER_H_ */