[34mFri Feb 19 15:53:35 2016 +0100[m [33m6b09122[32m (HEAD -> tcp-next)[m [34minternet: added tcp-bytes-in-flight test [35m [Natale Patriciello][m diff --git a/src/internet/test/tcp-bytes-in-flight-test.cc b/src/internet/test/tcp-bytes-in-flight-test.cc new file mode 100644 index 0000000..d46bfe6 --- /dev/null +++ b/src/internet/test/tcp-bytes-in-flight-test.cc @@ -0,0 +1,220 @@ +/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */ +/* + * Copyright (c) 2016 Natale Patriciello + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation; + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include "tcp-general-test.h" +#include "ns3/node.h" +#include "ns3/log.h" +#include "tcp-error-model.h" + +namespace ns3 { + +NS_LOG_COMPONENT_DEFINE ("TcpBytesInFlightTestSuite"); + +/** + * \brief Check the value of BytesInFlight against a home-made guess + * + * The guess is made wrt to segments that travel the network; we have, + * in theory, the possibility to know the real amount of bytes in flight. However + * this value is useless, since the sender bases its guess on the received ACK. + * + * \see Tx + * \see BytesInFlightTrace + */ +class TcpBytesInFlightTest : public TcpGeneralTest +{ +public: + TcpBytesInFlightTest (const std::string &desc, std::vector &toDrop); + +protected: + virtual Ptr CreateReceiverErrorModel (); + virtual void Rx (const Ptr p, const TcpHeader&h, SocketWho who); + virtual void Tx (const Ptr p, const TcpHeader&h, SocketWho who); + virtual void BytesInFlightTrace (uint32_t oldValue, uint32_t newValue); + + void PktDropped (const Ipv4Header &ipH, const TcpHeader& tcpH, Ptr p); + + void FinalChecks (); + +private: + uint32_t m_realBytesInFlight; + uint32_t m_guessedBytesInFlight; + uint32_t m_dupAckRecv; + SequenceNumber32 m_lastAckRecv; + SequenceNumber32 m_greatestSeqSent; + std::vector m_toDrop; // List of SequenceNumber to drop +}; + +TcpBytesInFlightTest::TcpBytesInFlightTest (const std::string &desc, std::vector &toDrop) + : TcpGeneralTest (desc, 500, 30, Seconds (0.01), Seconds (0.05), Seconds (2.0), + 0xffffffff,1, 500), + m_realBytesInFlight (0), + m_guessedBytesInFlight (0), + m_dupAckRecv (0), + m_lastAckRecv (1), + m_greatestSeqSent (0), + m_toDrop (toDrop) +{ +} + +Ptr +TcpBytesInFlightTest::CreateReceiverErrorModel () +{ + Ptr m_errorModel = CreateObject (); + for (std::vector::iterator it = m_toDrop.begin (); it != m_toDrop.end (); ++it) + { + m_errorModel->AddSeqToKill (SequenceNumber32 (*it)); + } + + m_errorModel->SetDropCallback (MakeCallback (&TcpBytesInFlightTest::PktDropped, this)); + + return m_errorModel; +} + +void +TcpBytesInFlightTest::PktDropped (const Ipv4Header &ipH, const TcpHeader &tcpH, + Ptr p) +{ + NS_LOG_DEBUG ("Drop seq= " << tcpH.GetSequenceNumber () << " size " << p->GetSize ()); + + // These bytes leave the world, they were not loved by anyone + m_realBytesInFlight -= p->GetSize (); +} + +void +TcpBytesInFlightTest::Rx (const Ptr p, const TcpHeader &h, SocketWho who) +{ + if (who == RECEIVER) + { + // Received has got data; bytes are not in flight anymore + m_realBytesInFlight -= p->GetSize (); + } + else if (who == SENDER) + { + if (h.GetAckNumber () > m_lastAckRecv) + { // New ack + uint32_t diff = h.GetAckNumber () - m_lastAckRecv; + NS_LOG_DEBUG ("Recv ACK=" << h.GetAckNumber ()); + + if (m_dupAckRecv > 0) + { // Previously we got some ACKs + if (h.GetAckNumber () >= m_greatestSeqSent) + { // This an ACK which acknowledge all the window + diff -= (m_dupAckRecv * GetSegSize (SENDER)); + + if (diff > m_guessedBytesInFlight) + { + // Our home-made guess is influenced also by retransmission + // so make sure that this does not overflow + diff = m_guessedBytesInFlight; + } + + m_dupAckRecv = 0; + } + else + { + // Partial ACK: Update the dupAck received count + m_dupAckRecv -= diff / GetSegSize (SENDER); + } + } + + if ((h.GetFlags () & TcpHeader::FIN) != 0 + || m_guessedBytesInFlight + 1 == diff) + { // received the ACK for the FIN (which includes 1 spurious byte) + diff -= 1; + } + m_guessedBytesInFlight -= diff; + m_lastAckRecv = h.GetAckNumber (); + NS_LOG_DEBUG ("Update m_guessedBytesInFlight to " << + m_guessedBytesInFlight); + } + else if (h.GetAckNumber () == m_lastAckRecv + && m_lastAckRecv != SequenceNumber32 (1) + && (h.GetFlags () & TcpHeader::FIN) == 0) + { + // For each dupack I should guess that a segment has been received + // Please do not count FIN and SYN/ACK as dupacks + m_guessedBytesInFlight -= GetSegSize (SENDER); + m_dupAckRecv++; + NS_LOG_DEBUG ("Dupack received, Update m_guessedBytesInFlight to " << + m_guessedBytesInFlight); + } + + } +} + +void +TcpBytesInFlightTest::Tx (const Ptr p, const TcpHeader &h, SocketWho who) +{ + if (who == SENDER) + { + m_realBytesInFlight += p->GetSize (); + if (m_greatestSeqSent <= h.GetSequenceNumber ()) + { // This is not a retransmission + m_guessedBytesInFlight += p->GetSize (); + m_greatestSeqSent = h.GetSequenceNumber (); + } + + // TODO: Maybe we need to account retransmission in another variable, + // such as m_guessedRetransOut ? + + NS_LOG_DEBUG ("TX size=" << p->GetSize () << " seq=" << h.GetSequenceNumber () << + " m_guessedBytesInFlight=" << m_guessedBytesInFlight); + } +} + +void +TcpBytesInFlightTest::BytesInFlightTrace (uint32_t oldValue, uint32_t newValue) +{ + NS_LOG_DEBUG ("Socket BytesInFlight=" << newValue << + " mine is=" << m_guessedBytesInFlight); + NS_TEST_ASSERT_MSG_EQ (m_guessedBytesInFlight, newValue, + "Guessed and measured bytes in flight differs"); +} + +void +TcpBytesInFlightTest::FinalChecks () +{ + NS_TEST_ASSERT_MSG_EQ (m_guessedBytesInFlight, 0, + "Still present bytes in flight at the end of the transmission"); +} + +//----------------------------------------------------------------------------- + +static class TcpBytesInFlightTestSuite : public TestSuite +{ +public: + TcpBytesInFlightTestSuite () : TestSuite ("tcp-bytes-in-flight-test", UNIT) + { + std::vector toDrop; + AddTestCase (new TcpBytesInFlightTest ("BytesInFlight value, no drop", toDrop), + TestCase::QUICK); + toDrop.push_back (4001); + AddTestCase (new TcpBytesInFlightTest ("BytesInFlight value, one drop", toDrop), + TestCase::QUICK); + toDrop.push_back (4001); + AddTestCase (new TcpBytesInFlightTest ("BytesInFlight value, two drop of same segment", toDrop), + TestCase::QUICK); + toDrop.pop_back (); + toDrop.push_back (4501); + AddTestCase (new TcpBytesInFlightTest ("BytesInFlight value, two drop of consecutive segments", toDrop), + TestCase::QUICK); + } +} g_tcpBytesInFlightTestSuite; + +} // namespace ns3 diff --git a/src/internet/wscript b/src/internet/wscript index 7f1e1d7..f1ed99b 100644 --- a/src/internet/wscript +++ b/src/internet/wscript @@ -243,6 +243,7 @@ def build(bld): 'test/tcp-hybla-test.cc', 'test/tcp-zero-window-test.cc', 'test/tcp-pkts-acked-test.cc', + 'test/tcp-bytes-in-flight-test.cc', 'test/udp-test.cc', 'test/ipv6-address-generator-test-suite.cc', 'test/ipv6-dual-stack-test-suite.cc',