/src/PcapPlusPlus/Packet++/header/GtpLayer.h

Source (jump to first uncovered line)
#pragma once

#include "Layer.h"

/// @file


/**
 * \namespace pcpp
 * \brief The main namespace for the PcapPlusPlus lib
 */
namespace pcpp
{

#pragma pack(push, 1)
  /**
   * @struct gtpv1_header
   * GTP v1 common message header
   */
  struct gtpv1_header
  {
#if (BYTE_ORDER == LITTLE_ENDIAN)
    /** A 1-bit value that states whether there is a N-PDU number optional field */
    uint8_t npduNumberFlag:1,
    /** A 1-bit value that states whether there is a Sequence Number optional field */
    sequenceNumberFlag:1,
    /** A 1-bit value that states whether there is an extension header optional field */
    extensionHeaderFlag:1,
    /** Reserved bit */
    reserved:1,
    /** A 1-bit value that differentiates GTP (value 1) from GTP' (value 0) */
    protocolType:1,
    /** GTP version */
    version:3;
#else
    /** GTP version */
    uint8_t version:3,
    /** A 1-bit value that differentiates GTP (value 1) from GTP' (value 0) */
    protocolType:1,
    /** Reserved bit */
    reserved:1,
    /** A 1-bit value that states whether there is an extension header optional field */
    extensionHeaderFlag:1,
    /** A 1-bit value that states whether there is a Sequence Number optional field */
    sequenceNumberFlag:1,
    /** A 1-bit value that states whether there is a N-PDU number optional field */
    npduNumberFlag:1;
#endif
    /** An 8-bit field that indicates the type of GTP message */
    uint8_t messageType;

    /** A 16-bit field that indicates the length of the payload in bytes (rest of the packet following the mandatory 8-byte GTP header). Includes the optional fields */
    uint16_t messageLength;

    /** Tunnel endpoint identifier - A 32-bit(4-octet) field used to multiplex different connections in the same GTP tunnel */
    uint32_t teid;
  };

#pragma pack(pop)

  /**
   * An enum representing the possible GTP v1 message types.
   * All of the message types except for #GtpV1_GPDU are considered GTP-C messages. #GtpV1_GPDU is considered a GTP-U message
   */
  enum GtpV1MessageType
  {
    /** GTPv1 Message Type Unknown */
    GtpV1_MessageTypeUnknown = 0,
    /** Echo Request */
    GtpV1_EchoRequest = 1,
    /** Echo Response */
    GtpV1_EchoResponse = 2,
    /** Version Not Supported */
    GtpV1_VersionNotSupported = 3,
    /** Node Alive Request */
    GtpV1_NodeAliveRequest = 4,
    /** Node Alive Response */
    GtpV1_NodeAliveResponse = 5,
    /** Redirection Request */
    GtpV1_RedirectionRequest = 6,
    /** Create PDP Context Request */
    GtpV1_CreatePDPContextRequest = 7,
    /** Create PDP Context Response */
    GtpV1_CreatePDPContextResponse = 16,
    /** Update PDP Context Request */
    GtpV1_UpdatePDPContextRequest = 17,
    /** Update PDP Context Response */
    GtpV1_UpdatePDPContextResponse = 18,
    /** Delete PDP Context Request */
    GtpV1_DeletePDPContextRequest = 19,
    /** Delete PDP Context Response */
    GtpV1_DeletePDPContextResponse = 20,
    /** Initiate PDP Context Activation Request */
    GtpV1_InitiatePDPContextActivationRequest = 22,
    /** Initiate PDP Context Activation Response */
    GtpV1_InitiatePDPContextActivationResponse = 23,
    /** Error Indication */
    GtpV1_ErrorIndication = 26,
    /** PDU Notification Request */
    GtpV1_PDUNotificationRequest = 27,
    /** PDU Notification Response */
    GtpV1_PDUNotificationResponse = 28,
    /** PDU Notification Reject Request */
    GtpV1_PDUNotificationRejectRequest = 29,
    /** PDU Notification Reject Response */
    GtpV1_PDUNotificationRejectResponse = 30,
    /** Supported Extensions Header Notification */
    GtpV1_SupportedExtensionsHeaderNotification = 31,
    /** Send Routing for GPRS Request */
    GtpV1_SendRoutingforGPRSRequest = 32,
    /** Send Routing for GPRS Response */
    GtpV1_SendRoutingforGPRSResponse = 33,
    /** Failure Report Request */
    GtpV1_FailureReportRequest = 34,
    /** Failure Report Response */
    GtpV1_FailureReportResponse = 35,
    /** Note MS Present Request */
    GtpV1_NoteMSPresentRequest = 36,
    /** Note MS Present Response */
    GtpV1_NoteMSPresentResponse = 37,
    /** Identification Request */
    GtpV1_IdentificationRequest = 38,
    /** Identification Response */
    GtpV1_IdentificationResponse = 39,
    /** SGSN Context Request */
    GtpV1_SGSNContextRequest = 50,
    /** SGSN Context Response */
    GtpV1_SGSNContextResponse = 51,
    /** SGSN Context Acknowledge */
    GtpV1_SGSNContextAcknowledge = 52,
    /** Forward Relocation Request */
    GtpV1_ForwardRelocationRequest = 53,
    /** Forward Relocation Response */
    GtpV1_ForwardRelocationResponse = 54,
    /** Forward Relocation Complete */
    GtpV1_ForwardRelocationComplete = 55,
    /** Relocation Cancel Request */
    GtpV1_RelocationCancelRequest = 56,
    /** Relocation Cancel Response */
    GtpV1_RelocationCancelResponse = 57,
    /** Forward SRNS Context */
    GtpV1_ForwardSRNSContext = 58,
    /** Forward Relocation Complete Acknowledge */
    GtpV1_ForwardRelocationCompleteAcknowledge = 59,
    /** Forward SRNS Context Acknowledge */
    GtpV1_ForwardSRNSContextAcknowledge = 60,
    /** UE Registration Request */
    GtpV1_UERegistrationRequest = 61,
    /** UE Registration Response */
    GtpV1_UERegistrationResponse = 62,
    /** RAN Information Relay */
    GtpV1_RANInformationRelay = 70,
    /** MBMS Notification Request */
    GtpV1_MBMSNotificationRequest = 96,
    /** MBMS Notification Response */
    GtpV1_MBMSNotificationResponse = 97,
    /** MBMS Notification Reject Request */
    GtpV1_MBMSNotificationRejectRequest = 98,
    /** MBMS Notification Reject Response */
    GtpV1_MBMSNotificationRejectResponse = 99,
    /** Create MBMS Notification Request */
    GtpV1_CreateMBMSNotificationRequest = 100,
    /** Create MBMS Notification Response */
    GtpV1_CreateMBMSNotificationResponse = 101,
    /** Update MBMS Notification Request */
    GtpV1_UpdateMBMSNotificationRequest = 102,
    /** Update MBMS Notification Response */
    GtpV1_UpdateMBMSNotificationResponse = 103,
    /** Delete MBMS Notification Request */
    GtpV1_DeleteMBMSNotificationRequest = 104,
    /** Delete MBMS Notification Response */
    GtpV1_DeleteMBMSNotificationResponse = 105,
    /** MBMS Registration Request */
    GtpV1_MBMSRegistrationRequest = 112,
    /** MBMS Registration Response */
    GtpV1_MBMSRegistrationResponse = 113,
    /** MBMS De-Registration Request */
    GtpV1_MBMSDeRegistrationRequest = 114,
    /** MBMS De-Registration Response */
    GtpV1_MBMSDeRegistrationResponse = 115,
    /** MBMS Session Start Request */
    GtpV1_MBMSSessionStartRequest = 116,
    /** MBMS Session Start Response */
    GtpV1_MBMSSessionStartResponse = 117,
    /** MBMS Session Stop Request */
    GtpV1_MBMSSessionStopRequest = 118,
    /** MBMS Session Stop Response */
    GtpV1_MBMSSessionStopResponse = 119,
    /** MBMS Session Update Request */
    GtpV1_MBMSSessionUpdateRequest = 120,
    /** MBMS Session Update Response */
    GtpV1_MBMSSessionUpdateResponse = 121,
    /** MS Info Change Request */
    GtpV1_MSInfoChangeRequest = 128,
    /** MS Info Change Response */
    GtpV1_MSInfoChangeResponse = 129,
    /** Data Record Transfer Request */
    GtpV1_DataRecordTransferRequest = 240,
    /** Data Record Transfer Response */
    GtpV1_DataRecordTransferResponse = 241,
    /** End Marker */
    GtpV1_EndMarker = 254,
    /** G-PDU */
    GtpV1_GPDU = 255
  };


  /**
   * @class GtpV1Layer
   * A class representing the [GTP v1](https://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol) protocol.
   */
  class GtpV1Layer : public Layer
  {
  private:
    struct gtpv1_header_extra
    {
      uint16_t sequenceNumber;
      uint8_t npduNumber;
      uint8_t nextExtensionHeader;
    };

    gtpv1_header_extra* getHeaderExtra() const;

    void init(GtpV1MessageType messageType, uint32_t teid, bool setSeqNum, uint16_t seqNum, bool setNpduNum, uint8_t npduNum);

  public:

    /**
     * @class GtpExtension
     * A class that represents [GTP header extensions](https://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol)
     */
    class GtpExtension
    {
      friend class GtpV1Layer;

    private:
      uint8_t* m_Data;
      size_t m_DataLen;
      uint8_t m_ExtType;

      GtpExtension(uint8_t* data, size_t dataLen, uint8_t type);

      void setNextHeaderType(uint8_t nextHeaderType);

      static GtpExtension createGtpExtension(uint8_t* data, size_t dataLen, uint8_t extType, uint16_t content);

    public:

      /**
       * An empty c'tor that creates an empty object, meaning one that isNull() returns "true")
       */
      GtpExtension();

      /**
       * A copy c'tor for this class
       * @param[in] other The GTP extension to copy from
       */
      GtpExtension(const GtpExtension& other);

      /**
       * An assignment operator for this class
       * @param[in] other The extension to assign from
       * @return A reference to the assignee
       */
      GtpExtension& operator=(const GtpExtension& other);

      /**
       * @return Instances of this class may be initialized as empty, meaning they don't contain any data. In
       * these cases this method returns true
       */
      bool isNull() const;

      /**
       * @return The extension type. If the object is empty a value of zero is returned
       */
      uint8_t getExtensionType() const;

      /**
       * @return The total length of the extension including the length and next extension type fields.
       * If the object is empty a value of zero is returned
       */
      size_t getTotalLength() const;

      /**
       * @return The length of the extension's content, excluding the extension length and next extension type fields.
       * If the object is empty a value of zero is returned
       */
      size_t getContentLength() const;

      /**
       * @return A byte array that includes the extension's content. The length of this array can be determined by
       * getContentLength(). If the object is empty a null value is returned
       */
      uint8_t* getContent() const;

      /**
       * @return The extension type of the next header. If there are no more header extensions or if this object is empty
       * a value of zero is returned
       */
      uint8_t getNextExtensionHeaderType() const;

      /**
       * @return An instance of this class representing the next extension header, if exists in the message. If there are
       * no more header extensions or if this object is empty an empty instance of GtpExtension is returned, meaning
       * one that GtpExtension#isNull() returns "true"
       */
      GtpExtension getNextExtension() const;
    }; // GtpExtension

    virtual ~GtpV1Layer() {}

     /** A constructor that creates the layer from an existing packet raw data
     * @param[in] data A pointer to the raw data
     * @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
     */
    GtpV1Layer(uint8_t* data, size_t dataLen, Layer* prevLayer, Packet* packet) : Layer(data, dataLen, prevLayer, packet) { m_Protocol = GTPv1; }

    /**
     * A constructor that creates a new GTPv1 layer and sets the message type and the TEID value
     * @param[in] messageType The GTPv1 message type to be set in the newly created layer
     * @param[in] teid The TEID value to be set in the newly created layer
     */
    GtpV1Layer(GtpV1MessageType messageType, uint32_t teid);

    /**
     * A constructor that creates a new GTPv1 layer and sets various parameters
     * @param[in] messageType The GTPv1 message type to be set in the newly created layer
     * @param[in] teid The TEID value to be set in the newly created layer
     * @param[in] setSeqNum A flag indicating whether to set a sequence number. If set to "false" then the parameter "seqNum" will be ignored
     * @param[in] seqNum The sequence number to be set in the newly created later. If "setSeqNum" is set to false this parameter will be ignored
     * @param[in] setNpduNum A flag indicating whether to set the N-PDU number. If set to "false" then the parameter "npduNum" will be ignored
     * @param[in] npduNum The N-PDU number to be set in the newly created later. If "setNpduNum" is set to false this parameter will be ignored
     */
    GtpV1Layer(GtpV1MessageType messageType, uint32_t teid, bool setSeqNum, uint16_t seqNum, bool setNpduNum, uint8_t npduNum);

    /**
     * A static method that takes a byte array and detects whether it is a GTP v1 message
     * @param[in] data A byte array
     * @param[in] dataSize The byte array size (in bytes)
     * @return True if the data is identified as GTP v1 message (GTP-C or GTP-U)
     */
    static bool isGTPv1(const uint8_t* data, size_t dataSize);

    /**
     * @return The GTP v1 common header structure. Notice this points directly to the data, so every change will change the actual packet data
     */
    gtpv1_header* getHeader() const { return (gtpv1_header*)m_Data; }

    /**
     * Get the sequence number if exists on the message (sequence number is an optional field in GTP messages)
     * @param[out] seqNumber Set with the sequence number value if exists in the layer. Otherwise remains unchanged
     * @return True if the sequence number field exists in layer, in which case seqNumber is set with the value.
     * Or false otherwise
     */
    bool getSequenceNumber(uint16_t& seqNumber) const;

    /**
     * Set a sequence number
     * @param[in] seqNumber The sequence number to set
     * @return True if the value was set successfully, false otherwise. In case of failure a corresponding error message will be written to log
     */
    bool setSequenceNumber(const uint16_t seqNumber);

    /**
     * Get the N-PDU number if exists on the message (N-PDU number is an optional field in GTP messages)
     * @param[out] npduNum Set with the N-PDU number value if exists in the layer. Otherwise remains unchanged
     * @return True if the N-PDU number field exists in layer, in which case npduNum is set with the value.
     * Or false otherwise
     */
    bool getNpduNumber(uint8_t& npduNum) const;

    /**
     * Set an N-PDU number
     * @param[in] npduNum The N-PDU number to set
     * @return True if the value was set successfully, false otherwise. In case of failure a corresponding error message will be written to log
     */
    bool setNpduNumber(const uint8_t npduNum);

    /**
     * Get the type of the next header extension if exists on the message (extensions are optional in GTP messages)
     * @param[out] nextExtType Set with the next header extension type if exists in layer. Otherwise remains unchanged
     * @return True if the message contains header extensions, in which case nextExtType is set to the next
     * header extension type. If there are no header extensions false is returned and nextExtType remains unchanged
     */
    bool getNextExtensionHeaderType(uint8_t& nextExtType) const;

    /**
     * @return An object that represents the next extension header, if exists in the message. If there are no extensions
     * an empty object is returned, meaning an object which GtpExtension#isNull() returns "true"
     */
    GtpExtension getNextExtension() const;

    /**
     * Add a GTPv1 header extension. It is assumed that the extension is 4 bytes in length and its content is 2 bytes in length.
     * If you need a different content size please reach out to me. This method takes care of extending the layer to make room for
     * the new extension and also sets the relevant flags and fields
     * @param[in] extensionType The type of the new extension
     * @param[in] extensionContent A 2-byte long content
     * @return An object representing the newly added extension. If there was an error adding the extension a null object will be
     * returned (meaning GtpExtension#isNull() will return "true") and a corresponding error message will be written to log
     */
    GtpExtension addExtension(uint8_t extensionType, uint16_t extensionContent);

    /**
     * @return The message type of this GTP packet
     */
    GtpV1MessageType getMessageType() const;

    /**
     * @return A string representation of the packet's message type
     */
    std::string getMessageTypeAsString() const;

    /**
     * @return True if this is a GTP-U message, false otherwise
     */
    bool isGTPUMessage() const;

    /**
     * @return True if this is a GTP-C message, false otherwise
     */
    bool isGTPCMessage() const;

    /**
     * A static method that checks whether the port is considered as GTPv1
     * @param[in] port The port number to be checked
     * @return True if the port matches those associated with the BGP protocol
     */
    static bool isGTPv1Port(uint16_t port) { return port == 2152 /* GTP-U */ || port == 2123 /* GTP-C */; }


    // implement abstract methods

    /**
     * Identifies the following next layers for GTP-U packets: IPv4Layer, IPv6Layer. Otherwise sets PayloadLayer
     */
    void parseNextLayer();

    /**
     * @return The size of the GTP header. For GTP-C packets the size is determined by the value of
     * gtpv1_header#messageLength and for GTP-U the size only includes the GTP header itself (meaning
     * the size of gtpv1_header plus the size of the optional fields such as sequence number, N-PDU
     * or extensions if exist)
     */
    size_t getHeaderLen() const;

    /**
     * Calculate the following fields:
     * - gtpv1_header#messageLength
     */
    void computeCalculateFields();

    std::string toString() const;

    OsiModelLayer getOsiModelLayer() const { return OsiModelTransportLayer; }
  };
}

Coverage Report

Created: 2024-02-25 06:29

Line	Count	Source (jump to first uncovered line)
1		#pragma once
2
3		#include "Layer.h"
4
5		/// @file
6
7
8		/**
9		* \namespace pcpp
10		* \brief The main namespace for the PcapPlusPlus lib
11		*/
12		namespace pcpp
13		{
14
15		#pragma pack(push, 1)
16		/**
17		* @struct gtpv1_header
18		* GTP v1 common message header
19		*/
20		struct gtpv1_header
21		{
22		#if (BYTE_ORDER == LITTLE_ENDIAN)
23		/** A 1-bit value that states whether there is a N-PDU number optional field */
24		uint8_t npduNumberFlag:1,
25		/** A 1-bit value that states whether there is a Sequence Number optional field */
26		sequenceNumberFlag:1,
27		/** A 1-bit value that states whether there is an extension header optional field */
28		extensionHeaderFlag:1,
29		/** Reserved bit */
30		reserved:1,
31		/** A 1-bit value that differentiates GTP (value 1) from GTP' (value 0) */
32		protocolType:1,
33		/** GTP version */
34		version:3;
35		#else
36		/** GTP version */
37		uint8_t version:3,
38		/** A 1-bit value that differentiates GTP (value 1) from GTP' (value 0) */
39		protocolType:1,
40		/** Reserved bit */
41		reserved:1,
42		/** A 1-bit value that states whether there is an extension header optional field */
43		extensionHeaderFlag:1,
44		/** A 1-bit value that states whether there is a Sequence Number optional field */
45		sequenceNumberFlag:1,
46		/** A 1-bit value that states whether there is a N-PDU number optional field */
47		npduNumberFlag:1;
48		#endif
49		/** An 8-bit field that indicates the type of GTP message */
50		uint8_t messageType;
51
52		/** A 16-bit field that indicates the length of the payload in bytes (rest of the packet following the mandatory 8-byte GTP header). Includes the optional fields */
53		uint16_t messageLength;
54
55		/** Tunnel endpoint identifier - A 32-bit(4-octet) field used to multiplex different connections in the same GTP tunnel */
56		uint32_t teid;
57		};
58
59		#pragma pack(pop)
60
61		/**
62		* An enum representing the possible GTP v1 message types.
63		* All of the message types except for #GtpV1_GPDU are considered GTP-C messages. #GtpV1_GPDU is considered a GTP-U message
64		*/
65		enum GtpV1MessageType
66		{
67		/** GTPv1 Message Type Unknown */
68		GtpV1_MessageTypeUnknown = 0,
69		/** Echo Request */
70		GtpV1_EchoRequest = 1,
71		/** Echo Response */
72		GtpV1_EchoResponse = 2,
73		/** Version Not Supported */
74		GtpV1_VersionNotSupported = 3,
75		/** Node Alive Request */
76		GtpV1_NodeAliveRequest = 4,
77		/** Node Alive Response */
78		GtpV1_NodeAliveResponse = 5,
79		/** Redirection Request */
80		GtpV1_RedirectionRequest = 6,
81		/** Create PDP Context Request */
82		GtpV1_CreatePDPContextRequest = 7,
83		/** Create PDP Context Response */
84		GtpV1_CreatePDPContextResponse = 16,
85		/** Update PDP Context Request */
86		GtpV1_UpdatePDPContextRequest = 17,
87		/** Update PDP Context Response */
88		GtpV1_UpdatePDPContextResponse = 18,
89		/** Delete PDP Context Request */
90		GtpV1_DeletePDPContextRequest = 19,
91		/** Delete PDP Context Response */
92		GtpV1_DeletePDPContextResponse = 20,
93		/** Initiate PDP Context Activation Request */
94		GtpV1_InitiatePDPContextActivationRequest = 22,
95		/** Initiate PDP Context Activation Response */
96		GtpV1_InitiatePDPContextActivationResponse = 23,
97		/** Error Indication */
98		GtpV1_ErrorIndication = 26,
99		/** PDU Notification Request */
100		GtpV1_PDUNotificationRequest = 27,
101		/** PDU Notification Response */
102		GtpV1_PDUNotificationResponse = 28,
103		/** PDU Notification Reject Request */
104		GtpV1_PDUNotificationRejectRequest = 29,
105		/** PDU Notification Reject Response */
106		GtpV1_PDUNotificationRejectResponse = 30,
107		/** Supported Extensions Header Notification */
108		GtpV1_SupportedExtensionsHeaderNotification = 31,
109		/** Send Routing for GPRS Request */
110		GtpV1_SendRoutingforGPRSRequest = 32,
111		/** Send Routing for GPRS Response */
112		GtpV1_SendRoutingforGPRSResponse = 33,
113		/** Failure Report Request */
114		GtpV1_FailureReportRequest = 34,
115		/** Failure Report Response */
116		GtpV1_FailureReportResponse = 35,
117		/** Note MS Present Request */
118		GtpV1_NoteMSPresentRequest = 36,
119		/** Note MS Present Response */
120		GtpV1_NoteMSPresentResponse = 37,
121		/** Identification Request */
122		GtpV1_IdentificationRequest = 38,
123		/** Identification Response */
124		GtpV1_IdentificationResponse = 39,
125		/** SGSN Context Request */
126		GtpV1_SGSNContextRequest = 50,
127		/** SGSN Context Response */
128		GtpV1_SGSNContextResponse = 51,
129		/** SGSN Context Acknowledge */
130		GtpV1_SGSNContextAcknowledge = 52,
131		/** Forward Relocation Request */
132		GtpV1_ForwardRelocationRequest = 53,
133		/** Forward Relocation Response */
134		GtpV1_ForwardRelocationResponse = 54,
135		/** Forward Relocation Complete */
136		GtpV1_ForwardRelocationComplete = 55,
137		/** Relocation Cancel Request */
138		GtpV1_RelocationCancelRequest = 56,
139		/** Relocation Cancel Response */
140		GtpV1_RelocationCancelResponse = 57,
141		/** Forward SRNS Context */
142		GtpV1_ForwardSRNSContext = 58,
143		/** Forward Relocation Complete Acknowledge */
144		GtpV1_ForwardRelocationCompleteAcknowledge = 59,
145		/** Forward SRNS Context Acknowledge */
146		GtpV1_ForwardSRNSContextAcknowledge = 60,
147		/** UE Registration Request */
148		GtpV1_UERegistrationRequest = 61,
149		/** UE Registration Response */
150		GtpV1_UERegistrationResponse = 62,
151		/** RAN Information Relay */
152		GtpV1_RANInformationRelay = 70,
153		/** MBMS Notification Request */
154		GtpV1_MBMSNotificationRequest = 96,
155		/** MBMS Notification Response */
156		GtpV1_MBMSNotificationResponse = 97,
157		/** MBMS Notification Reject Request */
158		GtpV1_MBMSNotificationRejectRequest = 98,
159		/** MBMS Notification Reject Response */
160		GtpV1_MBMSNotificationRejectResponse = 99,
161		/** Create MBMS Notification Request */
162		GtpV1_CreateMBMSNotificationRequest = 100,
163		/** Create MBMS Notification Response */
164		GtpV1_CreateMBMSNotificationResponse = 101,
165		/** Update MBMS Notification Request */
166		GtpV1_UpdateMBMSNotificationRequest = 102,
167		/** Update MBMS Notification Response */
168		GtpV1_UpdateMBMSNotificationResponse = 103,
169		/** Delete MBMS Notification Request */
170		GtpV1_DeleteMBMSNotificationRequest = 104,
171		/** Delete MBMS Notification Response */
172		GtpV1_DeleteMBMSNotificationResponse = 105,
173		/** MBMS Registration Request */
174		GtpV1_MBMSRegistrationRequest = 112,
175		/** MBMS Registration Response */
176		GtpV1_MBMSRegistrationResponse = 113,
177		/** MBMS De-Registration Request */
178		GtpV1_MBMSDeRegistrationRequest = 114,
179		/** MBMS De-Registration Response */
180		GtpV1_MBMSDeRegistrationResponse = 115,
181		/** MBMS Session Start Request */
182		GtpV1_MBMSSessionStartRequest = 116,
183		/** MBMS Session Start Response */
184		GtpV1_MBMSSessionStartResponse = 117,
185		/** MBMS Session Stop Request */
186		GtpV1_MBMSSessionStopRequest = 118,
187		/** MBMS Session Stop Response */
188		GtpV1_MBMSSessionStopResponse = 119,
189		/** MBMS Session Update Request */
190		GtpV1_MBMSSessionUpdateRequest = 120,
191		/** MBMS Session Update Response */
192		GtpV1_MBMSSessionUpdateResponse = 121,
193		/** MS Info Change Request */
194		GtpV1_MSInfoChangeRequest = 128,
195		/** MS Info Change Response */
196		GtpV1_MSInfoChangeResponse = 129,
197		/** Data Record Transfer Request */
198		GtpV1_DataRecordTransferRequest = 240,
199		/** Data Record Transfer Response */
200		GtpV1_DataRecordTransferResponse = 241,
201		/** End Marker */
202		GtpV1_EndMarker = 254,
203		/** G-PDU */
204		GtpV1_GPDU = 255
205		};
206
207
208		/**
209		* @class GtpV1Layer
210		* A class representing the [GTP v1](https://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol) protocol.
211		*/
212		class GtpV1Layer : public Layer
213		{
214		private:
215		struct gtpv1_header_extra
216		{
217		uint16_t sequenceNumber;
218		uint8_t npduNumber;
219		uint8_t nextExtensionHeader;
220		};
221
222		gtpv1_header_extra* getHeaderExtra() const;
223
224		void init(GtpV1MessageType messageType, uint32_t teid, bool setSeqNum, uint16_t seqNum, bool setNpduNum, uint8_t npduNum);
225
226		public:
227
228		/**
229		* @class GtpExtension
230		* A class that represents [GTP header extensions](https://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol)
231		*/
232		class GtpExtension
233		{
234		friend class GtpV1Layer;
235
236		private:
237		uint8_t* m_Data;
238		size_t m_DataLen;
239		uint8_t m_ExtType;
240
241		GtpExtension(uint8_t* data, size_t dataLen, uint8_t type);
242
243		void setNextHeaderType(uint8_t nextHeaderType);
244
245		static GtpExtension createGtpExtension(uint8_t* data, size_t dataLen, uint8_t extType, uint16_t content);
246
247		public:
248
249		/**
250		* An empty c'tor that creates an empty object, meaning one that isNull() returns "true")
251		*/
252		GtpExtension();
253
254		/**
255		* A copy c'tor for this class
256		* @param[in] other The GTP extension to copy from
257		*/
258		GtpExtension(const GtpExtension& other);
259
260		/**
261		* An assignment operator for this class
262		* @param[in] other The extension to assign from
263		* @return A reference to the assignee
264		*/
265		GtpExtension& operator=(const GtpExtension& other);
266
267		/**
268		* @return Instances of this class may be initialized as empty, meaning they don't contain any data. In
269		* these cases this method returns true
270		*/
271		bool isNull() const;
272
273		/**
274		* @return The extension type. If the object is empty a value of zero is returned
275		*/
276		uint8_t getExtensionType() const;
277
278		/**
279		* @return The total length of the extension including the length and next extension type fields.
280		* If the object is empty a value of zero is returned
281		*/
282		size_t getTotalLength() const;
283
284		/**
285		* @return The length of the extension's content, excluding the extension length and next extension type fields.
286		* If the object is empty a value of zero is returned
287		*/
288		size_t getContentLength() const;
289
290		/**
291		* @return A byte array that includes the extension's content. The length of this array can be determined by
292		* getContentLength(). If the object is empty a null value is returned
293		*/
294		uint8_t* getContent() const;
295
296		/**
297		* @return The extension type of the next header. If there are no more header extensions or if this object is empty
298		* a value of zero is returned
299		*/
300		uint8_t getNextExtensionHeaderType() const;
301
302		/**
303		* @return An instance of this class representing the next extension header, if exists in the message. If there are
304		* no more header extensions or if this object is empty an empty instance of GtpExtension is returned, meaning
305		* one that GtpExtension#isNull() returns "true"
306		*/
307		GtpExtension getNextExtension() const;
308		}; // GtpExtension
309
310	0	virtual ~GtpV1Layer() {}
311
312		/** A constructor that creates the layer from an existing packet raw data
313		* @param[in] data A pointer to the raw data
314		* @param[in] dataLen Size of the data in bytes
315		* @param[in] prevLayer A pointer to the previous layer
316		* @param[in] packet A pointer to the Packet instance where layer will be stored in
317		*/
318	33.5k	GtpV1Layer(uint8_t* data, size_t dataLen, Layer* prevLayer, Packet* packet) : Layer(data, dataLen, prevLayer, packet) { m_Protocol = GTPv1; }
319
320		/**
321		* A constructor that creates a new GTPv1 layer and sets the message type and the TEID value
322		* @param[in] messageType The GTPv1 message type to be set in the newly created layer
323		* @param[in] teid The TEID value to be set in the newly created layer
324		*/
325		GtpV1Layer(GtpV1MessageType messageType, uint32_t teid);
326
327		/**
328		* A constructor that creates a new GTPv1 layer and sets various parameters
329		* @param[in] messageType The GTPv1 message type to be set in the newly created layer
330		* @param[in] teid The TEID value to be set in the newly created layer
331		* @param[in] setSeqNum A flag indicating whether to set a sequence number. If set to "false" then the parameter "seqNum" will be ignored
332		* @param[in] seqNum The sequence number to be set in the newly created later. If "setSeqNum" is set to false this parameter will be ignored
333		* @param[in] setNpduNum A flag indicating whether to set the N-PDU number. If set to "false" then the parameter "npduNum" will be ignored
334		* @param[in] npduNum The N-PDU number to be set in the newly created later. If "setNpduNum" is set to false this parameter will be ignored
335		*/
336		GtpV1Layer(GtpV1MessageType messageType, uint32_t teid, bool setSeqNum, uint16_t seqNum, bool setNpduNum, uint8_t npduNum);
337
338		/**
339		* A static method that takes a byte array and detects whether it is a GTP v1 message
340		* @param[in] data A byte array
341		* @param[in] dataSize The byte array size (in bytes)
342		* @return True if the data is identified as GTP v1 message (GTP-C or GTP-U)
343		*/
344		static bool isGTPv1(const uint8_t* data, size_t dataSize);
345
346		/**
347		* @return The GTP v1 common header structure. Notice this points directly to the data, so every change will change the actual packet data
348		*/
349	151k	gtpv1_header* getHeader() const { return (gtpv1_header*)m_Data; }
350
351		/**
352		* Get the sequence number if exists on the message (sequence number is an optional field in GTP messages)
353		* @param[out] seqNumber Set with the sequence number value if exists in the layer. Otherwise remains unchanged
354		* @return True if the sequence number field exists in layer, in which case seqNumber is set with the value.
355		* Or false otherwise
356		*/
357		bool getSequenceNumber(uint16_t& seqNumber) const;
358
359		/**
360		* Set a sequence number
361		* @param[in] seqNumber The sequence number to set
362		* @return True if the value was set successfully, false otherwise. In case of failure a corresponding error message will be written to log
363		*/
364		bool setSequenceNumber(const uint16_t seqNumber);
365
366		/**
367		* Get the N-PDU number if exists on the message (N-PDU number is an optional field in GTP messages)
368		* @param[out] npduNum Set with the N-PDU number value if exists in the layer. Otherwise remains unchanged
369		* @return True if the N-PDU number field exists in layer, in which case npduNum is set with the value.
370		* Or false otherwise
371		*/
372		bool getNpduNumber(uint8_t& npduNum) const;
373
374		/**
375		* Set an N-PDU number
376		* @param[in] npduNum The N-PDU number to set
377		* @return True if the value was set successfully, false otherwise. In case of failure a corresponding error message will be written to log
378		*/
379		bool setNpduNumber(const uint8_t npduNum);
380
381		/**
382		* Get the type of the next header extension if exists on the message (extensions are optional in GTP messages)
383		* @param[out] nextExtType Set with the next header extension type if exists in layer. Otherwise remains unchanged
384		* @return True if the message contains header extensions, in which case nextExtType is set to the next
385		* header extension type. If there are no header extensions false is returned and nextExtType remains unchanged
386		*/
387		bool getNextExtensionHeaderType(uint8_t& nextExtType) const;
388
389		/**
390		* @return An object that represents the next extension header, if exists in the message. If there are no extensions
391		* an empty object is returned, meaning an object which GtpExtension#isNull() returns "true"
392		*/
393		GtpExtension getNextExtension() const;
394
395		/**
396		* Add a GTPv1 header extension. It is assumed that the extension is 4 bytes in length and its content is 2 bytes in length.
397		* If you need a different content size please reach out to me. This method takes care of extending the layer to make room for
398		* the new extension and also sets the relevant flags and fields
399		* @param[in] extensionType The type of the new extension
400		* @param[in] extensionContent A 2-byte long content
401		* @return An object representing the newly added extension. If there was an error adding the extension a null object will be
402		* returned (meaning GtpExtension#isNull() will return "true") and a corresponding error message will be written to log
403		*/
404		GtpExtension addExtension(uint8_t extensionType, uint16_t extensionContent);
405
406		/**
407		* @return The message type of this GTP packet
408		*/
409		GtpV1MessageType getMessageType() const;
410
411		/**
412		* @return A string representation of the packet's message type
413		*/
414		std::string getMessageTypeAsString() const;
415
416		/**
417		* @return True if this is a GTP-U message, false otherwise
418		*/
419		bool isGTPUMessage() const;
420
421		/**
422		* @return True if this is a GTP-C message, false otherwise
423		*/
424		bool isGTPCMessage() const;
425
426		/**
427		* A static method that checks whether the port is considered as GTPv1
428		* @param[in] port The port number to be checked
429		* @return True if the port matches those associated with the BGP protocol
430		*/
431	264k	static bool isGTPv1Port(uint16_t port) { return port == 2152 /* GTP-U / \|\| port == 2123 / GTP-C */; }
432
433
434		// implement abstract methods
435
436		/**
437		* Identifies the following next layers for GTP-U packets: IPv4Layer, IPv6Layer. Otherwise sets PayloadLayer
438		*/
439		void parseNextLayer();
440
441		/**
442		* @return The size of the GTP header. For GTP-C packets the size is determined by the value of
443		* gtpv1_header#messageLength and for GTP-U the size only includes the GTP header itself (meaning
444		* the size of gtpv1_header plus the size of the optional fields such as sequence number, N-PDU
445		* or extensions if exist)
446		*/
447		size_t getHeaderLen() const;
448
449		/**
450		* Calculate the following fields:
451		* - gtpv1_header#messageLength
452		*/
453		void computeCalculateFields();
454
455		std::string toString() const;
456
457	4.65k	OsiModelLayer getOsiModelLayer() const { return OsiModelTransportLayer; }
458		};
459		}