check MTU of remote router

This commit is contained in:
orignal 2014-09-14 17:54:55 -04:00
parent 4e213550ff
commit 37e4bc8e5b
2 changed files with 29 additions and 3 deletions

View file

@ -12,6 +12,29 @@ namespace ssu
SSUData::SSUData (SSUSession& session):
m_Session (session), m_ResendTimer (session.m_Server.GetService ())
{
m_PacketSize = SSU_MAX_PACKET_SIZE;
auto remoteRouter = session.GetRemoteRouter ();
if (remoteRouter)
{
auto ssuAddress = remoteRouter->GetSSUAddress ();
if (ssuAddress && ssuAddress->mtu)
{
m_PacketSize = ssuAddress->mtu - IPV4_HEADER_SIZE - UDP_HEADER_SIZE;
if (m_PacketSize > 0)
{
// make sure packet size multiple of 16
m_PacketSize >>= 4;
m_PacketSize <<= 4;
if (m_PacketSize > (int)SSU_MAX_PACKET_SIZE) m_PacketSize = SSU_MAX_PACKET_SIZE;
LogPrint ("MTU=", ssuAddress->mtu, " packet size=", m_PacketSize);
}
else
{
LogPrint ("Unexpected MTU ", ssuAddress->mtu);
m_PacketSize = SSU_MAX_PACKET_SIZE;
}
}
}
}
SSUData::~SSUData ()
@ -245,7 +268,7 @@ namespace ssu
sentMessage->numResends = 0;
auto& fragments = sentMessage->fragments;
msgID = htobe32 (msgID);
size_t payloadSize = SSU_PACKET_SIZE - sizeof (SSUHeader) - 9; // 9 = flag + #frg(1) + messageID(4) + frag info (3)
size_t payloadSize = m_PacketSize - sizeof (SSUHeader) - 9; // 9 = flag + #frg(1) + messageID(4) + frag info (3)
size_t len = msg->GetLength ();
uint8_t * msgBuf = msg->GetSSUHeader ();