libraries/pcappp/include/pcapplusplus/RawSocketDevice.h

165 lines
8.3 KiB
C++

#ifndef PCAPPP_RAW_SOCKET_DEVICE
#define PCAPPP_RAW_SOCKET_DEVICE
/// @file
#include "IpAddress.h"
#include "Device.h"
/**
* \namespace pcpp
* \brief The main namespace for the PcapPlusPlus lib
*/
namespace pcpp
{
/**
* @class RawSocketDevice
* A class that wraps the raw socket functionality. A raw socket is a network socket that allows direct sending and receiving
* of IP packets without any protocol-specific transport layer formatting
* (taken from Wikipedia: https://en.wikipedia.org/wiki/Network_socket#Raw_socket).
* This wrapper class enables creation of a raw socket, binding it to a network interface, and then receiving and sending
* packets on it. Current implementation supports only Windows and Linux because other platforms provide poor support for raw
* sockets making them practically unusable. There are also major differences between Linux and Windows in raw socket
* implementation, let's mention some of the:
* - On Windows administrative privileges are required for raw sockets creation, meaning the process running the code
* has to have these privileges. In Linux 'sudo' is required
* - On Windows raw sockets are implemented in L3, meaning the L2 (Ethernet) layer is omitted by the socket and only L3 and
* up are visible to the user. On Linux raw sockets are implemented on L2, meaning all layers (including the Ethernet
* data) are visible to the user.
* - On Windows sending packets is not supported, a raw socket can only receive packets. On Linux both send and receive are
* supported
* - Linux doesn't require binding to a specific network interface for receiving packets, but it does require binding
* for sending packets. Windows requires binding for receiving packets. For the sake of keeping a unified and simple cross-platform interface
* this class requires binding for both Linux and Windows, on both send and receive
*
* More details about opening the raw socket, receiving and sending packets are explained in the corresponding class methods.
* Raw sockets are supported for both IPv4 and IPv6, so you can create and bind raw sockets to each of the two.
* Also, there is no limit on the number of sockets opened for a specific IP address or network interface, so you can
* create multiple instances of this class and bind all of them to the same interface and IP address.
*/
class RawSocketDevice : public IDevice
{
public:
/**
* An enum for reporting packet receive results
*/
enum RecvPacketResult
{
/** Receive success */
RecvSuccess = 0,
/** Receive timeout - timeout expired without any packets being captured */
RecvTimeout = 1,
/** Receive would block - in non-blocking mode if there are no packets in the rx queue the receive method will return immediately with this return value */
RecvWouldBlock = 2,
/** Receive error, usually will be followed by an error log */
RecvError = 3
};
/*
* A c'tor for this class. This c'tor doesn't create the raw socket, but rather initializes internal structures. The actual
* raw socket creation is done in the open() method. Each raw socket is bound to a network interface which means
* packets will be received and sent from only from this network interface only
* @param[in] interfaceIP The network interface IP to bind the raw socket to. It can be either an IPv4 or IPv6 address
* (both are supported in raw sockets)
*/
RawSocketDevice(const IPAddress& interfaceIP);
/**
* A d'tor for this class. It closes the raw socket if not previously closed by calling close()
*/
~RawSocketDevice();
/**
* Receive a packet on the raw socket. This method has several modes of operation:
* - Blocking/non-blocking - in blocking mode the method will not return until a packet is received on the socket
* or until the timeout expires. In non-blocking mode it will return immediately and in case no packets are on the
* receive queue RawSocketDevice#RecvWouldBlock will be returned. Unless specified otherwise, the default value is
* blocking mode
* - Receive timeout - in blocking mode, the user can set a timeout to wait until a packet is received. If the timeout
* expires and no packets were received, the method will return RawSocketDevice#RecvTimeout. The default value is a
* negative value which means no timeout
*
* There is a slight difference on this method's behavior between Windows and Linux around how packets are received.
* On Linux the received packet contains all layers starting from the L2 (Ethernet). However on Windows raw socket are
* integrated in L3 level so the received packet contains only L3 (IP) layer and up.
* @param[out] rawPacket An empty packet instance where the received packet data will be written to
* @param[in] blocking Indicates whether to run in blocking or non-blocking mode. Default value is blocking
* @param[in] timeout When in blocking mode, specifies the timeout [in seconds] to wait for a packet. If timeout expired
* and no packets were captured the method will return RawSocketDevice#RecvTimeout. Zero or negative values mean no
* timeout. The default value is no timeout
* @return The method returns one on the following values:
* - RawSocketDevice#RecvSuccess is returned if a packet was received successfully
* - RawSocketDevice#RecvTimeout is returned if in blocking mode and timeout expired
* - RawSocketDevice#RecvWouldBlock is returned if in non-blocking mode and no packets were captured
* - RawSocketDevice#RecvError is returned if an error occurred such as device is not opened or the recv operation
* returned some error. A log message will be followed specifying the error and error code
*/
RecvPacketResult receivePacket(RawPacket& rawPacket, bool blocking = true, int timeout = -1);
/**
* Receive packets into a packet vector for a certain amount of time. This method starts a timer and invokes the
* receivePacket() method in blocking mode repeatedly until the timeout expires. All packets received successfully are
* put into a packet vector
* @param[out] packetVec The packet vector to add the received packet to
* @param[in] timeout Timeout in seconds to receive packets on the raw socket
* @param[out] failedRecv Number of receive attempts that failed
* @return The number of packets received successfully
*/
int receivePackets(RawPacketVector& packetVec, int timeout, int& failedRecv);
/**
* Send an Ethernet packet to the network. L2 protocols other than Ethernet are not supported in raw sockets.
* The entire packet is sent as is, including the original Ethernet and IP data.
* This method is only supported in Linux as Windows doesn't allow sending packets from raw sockets. Using
* it from other platforms will also return "false" with a corresponding error log message
* @param[in] rawPacket The packet to send
* @return True if packet was sent successfully or false if the socket is not open, if the packet is not Ethernet or
* if there was a failure sending the packet
*/
bool sendPacket(const RawPacket* rawPacket);
/**
* Send a set of Ethernet packets to the network. L2 protocols other than Ethernet are not supported by raw sockets.
* The entire packet is sent as is, including the original Ethernet and IP data.
* This method is only supported in Linux as Windows doesn't allow sending packets from raw sockets. Using it from
* other platforms will return "false" with an appropriate error log message
* @param[in] packetVec The set of packets to send
* @return The number of packets sent successfully. For packets that weren't sent successfully there will be a
* corresponding error message printed to log
*/
int sendPackets(const RawPacketVector& packetVec);
// overridden methods
/**
* Open the device by creating a raw socket and binding it to the network interface specified in the c'tor
* @return True if device was opened successfully, false otherwise with a corresponding error log message
*/
virtual bool open();
/**
* Close the raw socket
*/
virtual void close();
private:
enum SocketFamily
{
Ethernet = 0,
IPv4 = 1,
IPv6 = 2
};
SocketFamily m_SockFamily;
void* m_Socket;
IPAddress m_InterfaceIP;
RecvPacketResult getError(int& errorCode) const;
};
}
#endif // PCAPPP_RAW_SOCKET_DEVICE