int CSocket::Connect (CIPAddress &rForeignIP, u16 nForeignPort)
{
if (nForeignPort == 0)
{
return -1;
}
assert (m_pTransportLayer != 0);
if (m_hConnection >= 0)
{
if (m_nProtocol != IPPROTO_UDP)
{
return -1;
}
m_pTransportLayer->Disconnect (m_hConnection);
m_hConnection = -1;
}
assert (m_pNetConfig != 0);
if ( m_pNetConfig->GetIPAddress ()->IsNull () // from null source address
&& !( m_nProtocol == IPPROTO_UDP // only UDP broadcasts are allowed
&& rForeignIP.IsBroadcast ()))
{
return -1;
}
m_hConnection = m_pTransportLayer->Connect (rForeignIP, nForeignPort, m_nOwnPort, m_nProtocol);
return m_hConnection >= 0 ? 0 : m_hConnection;
}
int CUDPConnection::SendTo (const void *pData, unsigned nLength, int nFlags,
CIPAddress &rForeignIP, u16 nForeignPort)
{
if (m_nErrno < 0)
{
int nErrno = m_nErrno;
m_nErrno = 0;
return nErrno;
}
if (m_bActiveOpen)
{
// ignore rForeignIP and nForeignPort
return Send (pData, nLength, nFlags);
}
if ( nFlags != 0
&& nFlags != MSG_DONTWAIT)
{
return -1;
}
unsigned nPacketLength = sizeof (TUDPHeader) + nLength; // may wrap
if ( nPacketLength <= sizeof (TUDPHeader)
|| nPacketLength > FRAME_BUFFER_SIZE)
{
return -1;
}
assert (m_pNetConfig != 0);
if ( !m_bBroadcastsAllowed
&& ( rForeignIP.IsBroadcast ()
|| rForeignIP == *m_pNetConfig->GetBroadcastAddress ()))
{
return -1;
}
u8 PacketBuffer[nPacketLength];
TUDPHeader *pHeader = (TUDPHeader *) PacketBuffer;
pHeader->nSourcePort = le2be16 (m_nOwnPort);
pHeader->nDestPort = le2be16 (nForeignPort);
pHeader->nLength = le2be16 (nPacketLength);
pHeader->nChecksum = 0;
assert (pData != 0);
assert (nLength > 0);
memcpy (PacketBuffer+sizeof (TUDPHeader), pData, nLength);
m_Checksum.SetSourceAddress (*m_pNetConfig->GetIPAddress ());
m_Checksum.SetDestinationAddress (rForeignIP);
pHeader->nChecksum = m_Checksum.Calculate (PacketBuffer, nPacketLength);
assert (m_pNetworkLayer != 0);
boolean bOK = m_pNetworkLayer->Send (rForeignIP, PacketBuffer, nPacketLength, IPPROTO_UDP);
return bOK ? nLength : -1;
}
int CUDPConnection::PacketReceived (const void *pPacket, unsigned nLength,
CIPAddress &rSenderIP, CIPAddress &rReceiverIP, int nProtocol)
{
if (nProtocol != IPPROTO_UDP)
{
return 0;
}
if (nLength <= sizeof (TUDPHeader))
{
return -1;
}
TUDPHeader *pHeader = (TUDPHeader *) pPacket;
if (m_nOwnPort != be2le16 (pHeader->nDestPort))
{
return 0;
}
assert (m_pNetConfig != 0);
u16 nSourcePort = be2le16 (pHeader->nSourcePort);
if (m_bActiveOpen)
{
if (m_nForeignPort != nSourcePort)
{
return 0;
}
if ( m_ForeignIP != rSenderIP
&& !m_ForeignIP.IsBroadcast ()
&& m_ForeignIP != *m_pNetConfig->GetBroadcastAddress ())
{
return 0;
}
}
if (nLength < be2le16 (pHeader->nLength))
{
return -1;
}
if (pHeader->nChecksum != UDP_CHECKSUM_NONE)
{
m_Checksum.SetSourceAddress (rSenderIP);
m_Checksum.SetDestinationAddress (rReceiverIP);
if (m_Checksum.Calculate (pPacket, nLength) != CHECKSUM_OK)
{
return -1;
}
}
if ( !m_bBroadcastsAllowed
&& ( rReceiverIP.IsBroadcast ()
|| rReceiverIP == *m_pNetConfig->GetBroadcastAddress ()))
{
return 1;
}
nLength -= sizeof (TUDPHeader);
assert (nLength > 0);
TUDPPrivateData *pData = new TUDPPrivateData;
assert (pData != 0);
rSenderIP.CopyTo (pData->SourceAddress);
pData->nSourcePort = nSourcePort;
m_RxQueue.Enqueue ((u8 *) pPacket + sizeof (TUDPHeader), nLength, pData);
m_Event.Set ();
return 1;
}
