2024-02-21 14:52:47 +03:00

157 lines
4.1 KiB
C++

/*
* Copyright (c) 2017, Matias Fontanini
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following disclaimer
* in the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifndef TINS_TCP_IP_ACK_TRACKER_H
#define TINS_TCP_IP_ACK_TRACKER_H
#include <tins/config.h>
#ifdef TINS_HAVE_ACK_TRACKER
#include <vector>
#include <boost/icl/interval_set.hpp>
#include <tins/macros.h>
namespace Tins {
class PDU;
namespace TCPIP {
/**
* \brief Represents an acknowledged segment range
*
* The interval represented by this range is a closed interval [first, last].
*/
class TINS_API AckedRange {
public:
typedef boost::icl::discrete_interval<uint32_t> interval_type;
/**
* \brief Constructs an acked range
*
* \param first The first acked byte
* \param last The last acked byte (inclusive)
*/
AckedRange(uint32_t first, uint32_t last);
/**
* \brief Gets the next acked interval in this range
*
* If has_next() == false, then this returns an empty interval
*/
interval_type next();
/**
* Indicates whether there is still some non-consumed acked-interval in this
* range
*/
bool has_next() const;
/**
* Gets the first index acked by this range
*/
uint32_t first() const;
/**
* Gets the last index acked by this range
*/
uint32_t last() const;
private:
uint32_t first_;
uint32_t last_;
};
/**
* \brief Allows tracking acknowledged intervals in a TCP stream
*/
class TINS_API AckTracker {
public:
/**
* The type used to store ACKed intervals
*/
typedef boost::icl::interval_set<uint32_t> interval_set_type;
/**
* Default constructor
*/
AckTracker();
/**
* \brief Construct an instance using some attributes
*
* \param intial_ack The initial ACK number to use
* \param use_sack Indicate whether to use Selective ACKs to track ACK numbers
*/
AckTracker(uint32_t initial_ack, bool use_sack = true);
/**
* \brief Process a packet
*/
void process_packet(const PDU& packet);
/**
* \brief Indicates whether Selective ACKs should be processed
*/
void use_sack();
/**
* Retrieves the current ACK number in this tracker
*/
uint32_t ack_number() const;
/**
* \brief Retrieves all acked intervals by Selective ACKs
*/
const interval_set_type& acked_intervals() const;
/**
* \brief Indicates whether the given segment has been already ACKed
*
* \param sequence_number The segment's sequence number
* \param length The segment's length
*/
bool is_segment_acked(uint32_t sequence_number, uint32_t length) const;
private:
void process_sack(const std::vector<uint32_t>& sack);
void cleanup_sacked_intervals(uint32_t old_ack, uint32_t new_ack);
interval_set_type acked_intervals_;
uint32_t ack_number_;
bool use_sack_;
};
} // TCPIP
} // Tins
#endif // TINS_HAVE_ACK_TRACKER
#endif // TINS_TCP_IP_ACK_TRACKER_H