586 lines
17 KiB
C
586 lines
17 KiB
C
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/*++
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Copyright (c) 1999, Microsoft Corporation
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Module Name:
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sample\socket.c
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Assumes an IPv4 IPADDRESS for now...
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Abstract:
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The file contains functions to deal with sockets.
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Assumes an IPv4 IPADDRESS for now...
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--*/
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#include "pchsample.h"
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#pragma hdrstop
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#define START_SAMPLE_IO() ENTER_SAMPLE_API()
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#define FINISH_SAMPLE_IO() LEAVE_SAMPLE_API()
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////////////////////////////////////////
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// CALLBACKFUNCTIONS
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////////////////////////////////////////
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VOID
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WINAPI
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SocketCallbackSendCompletion (
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IN DWORD dwErr,
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IN DWORD dwNumSent,
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IN LPOVERLAPPED lpOverlapped
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)
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/*++
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Routine Description
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This routine is invoked by the I/O system upon completion of an
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operation. Runs in the context of an RTUTILS.DLL worker thread.
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Locks
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None.
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Arguments:
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dwErr system-supplied error code
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dwNumSent system-supplied byte-count
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lpOverlapped caller-supplied context area
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Return Value:
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None.
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--*/
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{
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PPACKET pPacket = CONTAINING_RECORD(lpOverlapped, PACKET, oOverlapped);
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TRACE3(ENTER, "Entering SocketCallbackSendCompletion: %u %u 0x%08x",
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dwErr, dwNumSent, lpOverlapped);
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PacketDisplay(pPacket);
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if ((dwErr != NO_ERROR) or // operation aborted
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(dwNumSent != pPacket->wsaBuffer.len)) // data not sent entirely
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{
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TRACE1(NETWORK, "Error %u sending packet", dwErr);
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LOGERR0(SENDTO_FAILED, dwErr);
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}
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PacketDestroy(pPacket); // destroy the packet structure
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TRACE0(LEAVE, "Leaving SocketCallbackSendCompletion");
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FINISH_SAMPLE_IO();
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}
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////////////////////////////////////////
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// APIFUNCTIONS
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////////////////////////////////////////
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DWORD
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SocketCreate (
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IN IPADDRESS ipAddress,
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IN HANDLE hEvent,
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OUT SOCKET *psSocket)
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/*++
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Routine Description
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Creates a socket.
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Locks
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None
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Arguments
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ipAddress ip address to bind the socket to
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hEvent the event to set when a packet arrives
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psSocket address of the socket to create
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Return Value
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NO_ERROR success
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Error Code o/w
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--*/
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{
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DWORD dwErr = NO_ERROR;
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PCHAR pszBuffer;
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SOCKADDR_IN sinSockAddr;
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BOOL bDontLinger, bReuse, bLoopback;
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struct linger lLinger = { 0, 0 };
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UCHAR ucTTL;
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struct ip_mreq imMulticast;
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// validate parameters
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if ((!psSocket or (*psSocket != INVALID_SOCKET)) or
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!IP_VALID(ipAddress) or
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(hEvent is INVALID_HANDLE_VALUE))
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return ERROR_INVALID_PARAMETER;
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// default return value
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*psSocket = INVALID_SOCKET;
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pszBuffer = INET_NTOA(ipAddress);
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do // breakout loop
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{
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// create socket
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*psSocket = WSASocket(AF_INET, // address family
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SOCK_RAW, // type
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PROTO_IP_SAMPLE, // protocol
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NULL,
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0,
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WSA_FLAG_OVERLAPPED);
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if(*psSocket is INVALID_SOCKET)
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{
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dwErr = WSAGetLastError();
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TRACE0(NETWORK, "Could not create socket");
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break;
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}
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// associate the socket with our I/O completion port. the callback
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// function is invoked when an overlapped I/O operation completes.
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// this would be the send operation!
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dwErr = SetIoCompletionProc((HANDLE) *psSocket,
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SocketCallbackSendCompletion);
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if (dwErr != NO_ERROR)
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{
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TRACE0(NETWORK, "Could not associate callback function");
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break;
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}
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// set SO_LINGER to off
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// do not linger on close waiting for unsent data to be sent
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bDontLinger = TRUE;
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if (setsockopt(*psSocket,
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SOL_SOCKET,
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SO_DONTLINGER,
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(const char *) &bDontLinger,
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sizeof(BOOL)) is SOCKET_ERROR)
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{
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TRACE2(NETWORK,
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"Error %u setting linger option on %s, continuing...",
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WSAGetLastError(), pszBuffer);
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}
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// set to SO_REUSEADDR
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// allow socket to be bound to an address that is already in use
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bReuse = TRUE;
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if (setsockopt(*psSocket,
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SOL_SOCKET,
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SO_REUSEADDR,
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(const char *) &bReuse,
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sizeof(BOOL)) is SOCKET_ERROR)
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{
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TRACE2(NETWORK,
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"Error %u seting reuse option on %s, continuing...",
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WSAGetLastError(), pszBuffer);
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}
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// bind to the specified IPv4 addresses
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ZeroMemory(&sinSockAddr, sizeof(SOCKADDR_IN));
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sinSockAddr.sin_family = AF_INET;
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sinSockAddr.sin_addr.s_addr = ipAddress;
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sinSockAddr.sin_port = 0;
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if (bind(*psSocket, (LPSOCKADDR) &sinSockAddr, sizeof(SOCKADDR_IN))
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is SOCKET_ERROR)
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{
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dwErr = WSAGetLastError();
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TRACE0(NETWORK, "Could not bind socket");
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LOGERR1(BIND_IF_FAILED, pszBuffer, dwErr);
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break;
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}
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// allow multicast traffic to be sent out this interface
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if (setsockopt(*psSocket,
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IPPROTO_IP,
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IP_MULTICAST_IF,
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(const char *) &sinSockAddr.sin_addr,
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sizeof(IN_ADDR)) is SOCKET_ERROR)
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{
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dwErr = WSAGetLastError();
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TRACE2(NETWORK,
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"Error %u setting interface %s as multicast...",
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dwErr, pszBuffer);
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LOGERR1(SET_MCAST_IF_FAILED, pszBuffer, dwErr);
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break;
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}
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// set loopback to ignore self generated packets.
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bLoopback = FALSE;
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if (setsockopt(*psSocket,
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IPPROTO_IP,
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IP_MULTICAST_LOOP,
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(const char *) &bLoopback,
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sizeof(BOOL)) is SOCKET_ERROR)
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{
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TRACE2(NETWORK,
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"Error %u setting loopback to FALSE on %s, continuing...",
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WSAGetLastError(), pszBuffer);
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}
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// set TTL to 1 to restrict packet to within subnet (default anyway)
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ucTTL = 1;
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if (setsockopt(*psSocket,
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IPPROTO_IP,
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IP_MULTICAST_TTL,
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(const char *) &ucTTL,
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sizeof(UCHAR)) is SOCKET_ERROR)
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{
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TRACE2(NETWORK,
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"Error %u setting mcast ttl to 1 on %s, continuing...",
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WSAGetLastError(), pszBuffer);
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}
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// join the multicast session on SAMPLE_PROTOCOL_MULTICAST_GROUP.
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imMulticast.imr_multiaddr.s_addr = SAMPLE_PROTOCOL_MULTICAST_GROUP;
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imMulticast.imr_interface.s_addr = ipAddress;
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if (setsockopt(*psSocket,
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IPPROTO_IP,
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IP_ADD_MEMBERSHIP,
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(const char *) &imMulticast,
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sizeof(struct ip_mreq)) is SOCKET_ERROR)
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{
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dwErr = WSAGetLastError();
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TRACE0(NETWORK, "Could not join multicast group on socket");
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LOGERR1(JOIN_GROUP_FAILED, pszBuffer, dwErr);
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break;
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}
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// associate hReceiveEvent with the receive network event
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if (WSAEventSelect(*psSocket, (WSAEVENT) hEvent, FD_READ)
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is SOCKET_ERROR)
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{
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dwErr = WSAGetLastError();
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TRACE1(NETWORK, "Error %u calling WSAEventSelect()", dwErr);
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LOGERR0(EVENTSELECT_FAILED, dwErr);
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break;
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}
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} while(FALSE);
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if (dwErr != NO_ERROR)
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{
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TRACE2(NETWORK, "Error %u creating socket for %s", dwErr, pszBuffer);
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LOGERR0(CREATE_SOCKET_FAILED, dwErr);
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SocketDestroy(*psSocket);
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*psSocket = INVALID_SOCKET;
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}
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return dwErr;
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}
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DWORD
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SocketDestroy (
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IN SOCKET sSocket)
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/*++
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Routine Description
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Closes a socket.
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Locks
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None
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Arguments
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sSocket the socket to close
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Return Value
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NO_ERROR success
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Error Code o/w
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--*/
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{
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DWORD dwErr = NO_ERROR;
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if (sSocket is INVALID_SOCKET)
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return NO_ERROR;
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/*
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// closing a socket with closesocket also cancels the association and
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// selection of network events specified in WSAEventSelect. redundant!
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if (WSAEventSelect(sSocket, (WSAEVENT) NULL, 0) is SOCKET_ERROR)
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{
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dwErr = WSAGetLastError();
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TRACE1(NETWORK, "Error %u clearing socket-event association", dwErr);
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LOGERR0(EVENTSELECT_FAILED, dwErr);
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}
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*/
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// close the socket
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if (closesocket(sSocket) != NO_ERROR)
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{
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dwErr = WSAGetLastError();
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TRACE1(NETWORK, "Error %u closing socket", dwErr);
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LOGERR0(DESTROY_SOCKET_FAILED, dwErr);
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}
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return dwErr;
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}
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DWORD
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SocketSend (
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IN SOCKET sSocket,
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IN IPADDRESS ipDestination,
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IN PPACKET pPacket)
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/*++
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Routine Description
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Send a packet to its destination and destroy it.
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Asynchronous.
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Locks
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None
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Arguments
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sSocket the socket to send the packet over
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ipDestination the packet's destination
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pPacket the packet to send out
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Return Value
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NO_ERROR success
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Error Code o/w
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--*/
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{
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DWORD dwErr = NO_ERROR;
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SOCKADDR_IN sinDestination;
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DWORD dwScratch;
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if (!START_SAMPLE_IO()) { return ERROR_CAN_NOT_COMPLETE; }
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// validate parameters
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if ((sSocket is INVALID_SOCKET) or !pPacket)
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return ERROR_INVALID_PARAMETER;
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ZeroMemory(&sinDestination, sizeof(SOCKADDR_IN));
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sinDestination.sin_family = AF_INET;
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sinDestination.sin_addr.s_addr = ipDestination;
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sinDestination.sin_port = 0;
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dwErr = WSASendTo(sSocket,
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&(pPacket->wsaBuffer), // buffer and length
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1, // only one wsabuf exists
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&dwScratch, // unused
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0, // no flags
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(PSOCKADDR) &sinDestination,
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sizeof(SOCKADDR_IN),
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&pPacket->oOverlapped, // context upon completion
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NULL); // no completion routine
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// completion routine (SocketCallbackSendCompletion) queued
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if (((dwErr is SOCKET_ERROR) and (WSAGetLastError() is WSA_IO_PENDING)) or
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(dwErr is NO_ERROR))
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{
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return NO_ERROR;
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}
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// completion routine (SocketCallbackSendCompletion) not queued
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dwErr = WSAGetLastError();
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TRACE1(NETWORK, "Error %u sending packet", dwErr);
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LOGERR0(SENDTO_FAILED, dwErr);
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FINISH_SAMPLE_IO();
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return dwErr;
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}
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DWORD
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SocketReceive (
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IN SOCKET sSocket,
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IN PPACKET pPacket)
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/*++
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Routine Description
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Receive a packet on a socket.
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This routine is written so that it could dynamically allocate a buffer,
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not knowing a priori the maximum size of the protocol's packet. It is
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synchronous, treating sSocket as a non overlapped socket.
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Locks
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None
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Arguments
|
||
|
|
sSocket the socket to send the packet over
|
||
|
|
pPacket the packet to send out
|
||
|
|
|
||
|
|
Return Value
|
||
|
|
NO_ERROR success
|
||
|
|
Error Code o/w
|
||
|
|
|
||
|
|
--*/
|
||
|
|
#define IPv4_PREVIEW_SIZE 4
|
||
|
|
#define IPv4_LENGTH_OFFSET 2
|
||
|
|
{
|
||
|
|
DWORD dwErr = NO_ERROR;
|
||
|
|
BYTE rgbyPreview[IPv4_PREVIEW_SIZE];
|
||
|
|
DWORD dwNumReceived, dwFlags;
|
||
|
|
INT iSourceLength;
|
||
|
|
SOCKADDR_IN sinSource;
|
||
|
|
DWORD dwPacketLength;
|
||
|
|
|
||
|
|
// validate parameters
|
||
|
|
if ((sSocket is INVALID_SOCKET) or !pPacket)
|
||
|
|
return ERROR_INVALID_PARAMETER;
|
||
|
|
|
||
|
|
do // breakout loop
|
||
|
|
{
|
||
|
|
// read enuf to figure length
|
||
|
|
pPacket->wsaBuffer.buf = rgbyPreview;
|
||
|
|
pPacket->wsaBuffer.len = IPv4_PREVIEW_SIZE;
|
||
|
|
dwFlags = MSG_PEEK;
|
||
|
|
iSourceLength = sizeof(SOCKADDR_IN);
|
||
|
|
|
||
|
|
dwErr = WSARecvFrom(sSocket,
|
||
|
|
&(pPacket->wsaBuffer), // buffer and length
|
||
|
|
1, // only one wsabuf exists
|
||
|
|
&dwNumReceived, // # bytes received
|
||
|
|
&dwFlags, // flags
|
||
|
|
(PSOCKADDR) &sinSource,
|
||
|
|
&iSourceLength,
|
||
|
|
NULL, // no context
|
||
|
|
NULL); // no completion routine
|
||
|
|
if (dwErr != SOCKET_ERROR) // there should have been an error
|
||
|
|
break;
|
||
|
|
dwErr = WSAGetLastError();
|
||
|
|
if (dwErr != WSAEMSGSIZE) // of this kind
|
||
|
|
break;
|
||
|
|
if (dwNumReceived != pPacket->wsaBuffer.len)
|
||
|
|
{
|
||
|
|
dwErr = ERROR_CAN_NOT_COMPLETE;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
// calculate the packet length
|
||
|
|
dwPacketLength = ntohs(*((PUSHORT)(rgbyPreview + IPv4_LENGTH_OFFSET)));
|
||
|
|
if (dwPacketLength > MAX_PACKET_LENGTH)
|
||
|
|
{
|
||
|
|
dwErr = ERROR_CAN_NOT_COMPLETE;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
// read the entire packet, the buffer could be dynamically allocated
|
||
|
|
pPacket->wsaBuffer.buf = pPacket->rgbyBuffer;
|
||
|
|
pPacket->wsaBuffer.len = dwPacketLength;
|
||
|
|
dwFlags = 0;
|
||
|
|
iSourceLength = sizeof(SOCKADDR_IN);
|
||
|
|
|
||
|
|
dwErr = WSARecvFrom(sSocket,
|
||
|
|
&(pPacket->wsaBuffer), // buffer and length
|
||
|
|
1, // only one wsabuf exists
|
||
|
|
&dwNumReceived, // # bytes received
|
||
|
|
&dwFlags, // flags
|
||
|
|
(PSOCKADDR) &sinSource,
|
||
|
|
&iSourceLength,
|
||
|
|
NULL, // no context
|
||
|
|
NULL); // no completion routine
|
||
|
|
if (dwErr is SOCKET_ERROR)
|
||
|
|
{
|
||
|
|
dwErr = WSAGetLastError();
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
if (dwPacketLength != dwNumReceived)
|
||
|
|
{
|
||
|
|
dwErr = ERROR_CAN_NOT_COMPLETE;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
pPacket->ipSource = sinSource.sin_addr.s_addr;
|
||
|
|
pPacket->wsaBuffer.len = dwNumReceived;
|
||
|
|
|
||
|
|
dwErr = NO_ERROR;
|
||
|
|
} while (FALSE);
|
||
|
|
|
||
|
|
if (dwErr != NO_ERROR)
|
||
|
|
{
|
||
|
|
TRACE1(NETWORK, "Error %u receiving packet", dwErr);
|
||
|
|
LOGERR0(RECVFROM_FAILED, dwErr);
|
||
|
|
}
|
||
|
|
|
||
|
|
return dwErr;
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
|
||
|
|
BOOL
|
||
|
|
SocketReceiveEvent (
|
||
|
|
IN SOCKET sSocket)
|
||
|
|
/*++
|
||
|
|
|
||
|
|
Routine Description
|
||
|
|
Indicates whether a receive event occured on a socket. The recording
|
||
|
|
of network events commences when WSAEventSelect is called with a
|
||
|
|
nonzero lNetworkEvents parameter (i.e. the socket is activated) and
|
||
|
|
remains in effect until another call is made to WSAEventSelect with the
|
||
|
|
lNetworkEvents parameter set to zero (i.e. the socket is deactivated).
|
||
|
|
|
||
|
|
Locks
|
||
|
|
None
|
||
|
|
|
||
|
|
Arguments
|
||
|
|
sSocket the socket to check for packet reception
|
||
|
|
|
||
|
|
Return Value
|
||
|
|
TRUE receive event did occur
|
||
|
|
FALSE o/w
|
||
|
|
|
||
|
|
--*/
|
||
|
|
{
|
||
|
|
DWORD dwErr = NO_ERROR;
|
||
|
|
WSANETWORKEVENTS wsaEvent;
|
||
|
|
|
||
|
|
// validate parameters
|
||
|
|
if (sSocket is INVALID_SOCKET)
|
||
|
|
return ERROR_INVALID_PARAMETER;
|
||
|
|
|
||
|
|
do // breakout loop
|
||
|
|
{
|
||
|
|
// enumerate network events to see if any packets have arrived on
|
||
|
|
dwErr = WSAEnumNetworkEvents(sSocket, NULL, &wsaEvent);
|
||
|
|
if (dwErr != NO_ERROR)
|
||
|
|
{
|
||
|
|
TRACE1(NETWORK, "Error %u enumerating network events", dwErr);
|
||
|
|
LOGERR0(ENUM_NETWORK_EVENTS_FAILED, dwErr);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
// see if the input bit is set
|
||
|
|
if (!(wsaEvent.lNetworkEvents & FD_READ))
|
||
|
|
{
|
||
|
|
dwErr = SOCKET_ERROR;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
// the input bit is set, now see if there was an error
|
||
|
|
dwErr = wsaEvent.iErrorCode[FD_READ_BIT];
|
||
|
|
if (dwErr != NO_ERROR)
|
||
|
|
{
|
||
|
|
TRACE1(NETWORK, "Error %u in input record", dwErr);
|
||
|
|
LOGERR0(INPUT_RECORD_ERROR, dwErr);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
} while (FALSE);
|
||
|
|
|
||
|
|
if (dwErr is NO_ERROR)
|
||
|
|
return TRUE;
|
||
|
|
|
||
|
|
return FALSE;
|
||
|
|
}
|