Leaked source code of windows server 2003
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317 lines
8.6 KiB

#include "stdafx.h"
SYNC_COUNTER Q931SyncCounter;
ASYNC_ACCEPT Q931AsyncAccept;
SOCKADDR_IN Q931ListenSocketAddress;
HANDLE Q931LoopbackRedirectHandle;
static
HRESULT
Q931AsyncAcceptFunctionInternal (
IN PVOID Context,
IN SOCKET Socket,
IN SOCKADDR_IN * LocalAddress,
IN SOCKADDR_IN * RemoteAddress
);
void
Q931AsyncAcceptFunction (
IN PVOID Context,
IN SOCKET Socket,
IN SOCKADDR_IN * LocalAddress,
IN SOCKADDR_IN * RemoteAddress
)
{
HRESULT Result;
Result = Q931AsyncAcceptFunctionInternal (
Context,
Socket,
LocalAddress,
RemoteAddress
);
if (S_OK != Result) {
if (INVALID_SOCKET != Socket) {
closesocket (Socket);
Socket = INVALID_SOCKET;
}
}
}
static
HRESULT
Q931AsyncAcceptFunctionInternal (
IN PVOID Context,
IN SOCKET Socket,
IN SOCKADDR_IN * LocalAddress,
IN SOCKADDR_IN * RemoteAddress
)
{
CALL_BRIDGE * CallBridge;
HRESULT Result;
NAT_KEY_SESSION_MAPPING_EX_INFORMATION RedirectInformation;
ULONG RedirectInformationLength;
ULONG Error;
DWORD BestInterfaceAddress;
DebugF (_T("Q931: ----------------------------------------------------------------------\n"));
#if DBG
ExposeTimingWindow ();
#endif
// a new Q.931 connection has been accepted from the network.
// first, we determine the original addresses of the transport connection.
// if the connection was redirected to our socket (due to NAT),
// then the query of the NAT redirect table will yield the original transport addresses.
// if an errant client has connected to our service, well, we really didn't
// intend for that to happen, so we just immediately close the socket.
assert (NatHandle);
RedirectInformationLength = sizeof (RedirectInformation);
Result = NatLookupAndQueryInformationSessionMapping (
NatHandle,
IPPROTO_TCP,
LocalAddress -> sin_addr.s_addr,
LocalAddress -> sin_port,
RemoteAddress -> sin_addr.s_addr,
RemoteAddress -> sin_port,
&RedirectInformation,
&RedirectInformationLength,
NatKeySessionMappingExInformation);
if (STATUS_SUCCESS != STATUS_SUCCESS) {
DebugError (Result, _T("Q931: New connection was accepted, but it is not in the NAT redirect table -- connection will be rejected.\n"));
return Result;
}
Error = GetBestInterfaceAddress (ntohl (RedirectInformation.DestinationAddress), &BestInterfaceAddress);
if (ERROR_SUCCESS != Error) {
if (WSAEHOSTUNREACH == Error) {
Error = RasAutoDialSharedConnection ();
if (ERROR_SUCCESS != Error) {
DebugF (_T("Q931: RasAutoDialSharedConnection failed. Error=%d\n"), Error);
}
} else {
DebugError (Error, _T("LDAP: Failed to get interface address for the destination.\n"));
return HRESULT_FROM_WIN32 (Error);
}
}
// based on the source address of the socket, we decide whether the connection
// came from an internal or external client. this will govern later decisions
// on how the call is routed.
#if DBG
BOOL IsPrivateOrLocalSource;
BOOL IsPublicDestination;
Result = ::IsPrivateAddress (ntohl (RedirectInformation.SourceAddress), &IsPrivateOrLocalSource);
if (S_OK != Result) {
return Result;
}
IsPrivateOrLocalSource = IsPrivateOrLocalSource || ::NhIsLocalAddress (RedirectInformation.SourceAddress);
Result = ::IsPublicAddress (ntohl (RedirectInformation.DestinationAddress), &IsPublicDestination);
if (S_OK != Result) {
return Result;
}
if (::NhIsLocalAddress (RedirectInformation.SourceAddress) &&
::NhIsLocalAddress (RedirectInformation.DestinationAddress)) {
Debug (_T("Q931: New LOCAL connection.\n"));
} else {
if (IsPrivateOrLocalSource && IsPublicDestination) {
Debug (_T("Q931: New OUTBOUND connection.\n"));
} else {
Debug (_T("Q931: New INBOUND connection.\n"));
}
}
#endif // DBG
DebugF (_T("Q931: Connection redirected: (%08X:%04X -> %08X:%04X) => (%08X:%04X -> %08X:%04X).\n"),
ntohl (RedirectInformation.SourceAddress),
ntohs (RedirectInformation.SourcePort),
ntohl (RedirectInformation.DestinationAddress),
ntohs (RedirectInformation.DestinationPort),
ntohl (RedirectInformation.NewSourceAddress),
ntohs (RedirectInformation.NewSourcePort),
ntohl (RedirectInformation.NewDestinationAddress),
ntohs (RedirectInformation.NewDestinationPort));
CallBridge = new CALL_BRIDGE (&RedirectInformation);
if (!CallBridge) {
DebugF (_T("Q931: Failed to allocate CALL_BRIDGE.\n"));
return E_OUTOFMEMORY;
}
CallBridge -> AddRef ();
// Add the call-bridge to the list. Doing so makes an additional reference
// to the object, which is retained until the object is destroyed by calling
// RemoveCallBridge.
if (CallBridgeList.InsertCallBridge (CallBridge) == S_OK) {
// should we check the local address or the caller's address ?
// The problem is that if someone tries to connect to the
// external IP address from inside, they will still probably succeed
Result = CallBridge -> Initialize (
Socket,
LocalAddress,
RemoteAddress,
&RedirectInformation
);
if (Result != S_OK) {
CallBridge -> TerminateExternal ();
DebugF (_T("Q931: 0x%x accepted new client, but failed to initialize.\n"), CallBridge);
// Probably there was something wrong with just this
// Init failure. Continue to accept more Q.931 connections.
}
}
CallBridge -> Release ();
return Result;
}
HRESULT
Q931CreateBindSocket (
void
)
{
HRESULT Result;
SOCKADDR_IN SocketAddress;
SocketAddress.sin_family = AF_INET;
SocketAddress.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
SocketAddress.sin_port = htons (0); // request dynamic port
Result = Q931AsyncAccept.StartIo (
&SocketAddress,
Q931AsyncAcceptFunction,
NULL
);
if (Result != S_OK) {
DebugError (Result, _T("Q931: Failed to create and bind socket.\n"));
return Result;
}
DebugF (_T("Q931: Asynchronous Accept started.\n"));
Result = Q931AsyncAccept.GetListenSocketAddress (&Q931ListenSocketAddress);
if (Result != S_OK) {
DebugError (Result, _T("Q931: Failed to get listen socket address.\n"));
return Result;
}
return S_OK;
}
void
Q931CloseSocket (
void
)
{
ZeroMemory ((PVOID)&Q931ListenSocketAddress, sizeof (SOCKADDR_IN));
Q931AsyncAccept.StopWait ();
}
HRESULT
Q931StartLoopbackRedirect (
void
)
{
NTSTATUS Status;
Status = NatCreateDynamicAdapterRestrictedPortRedirect (
NatRedirectFlagLoopback | NatRedirectFlagSendOnly,
IPPROTO_TCP,
htons (Q931_TSAP_IP_TCP),
Q931ListenSocketAddress.sin_addr.s_addr,
Q931ListenSocketAddress.sin_port,
::NhMapAddressToAdapter (htonl (INADDR_LOOPBACK)),
MAX_LISTEN_BACKLOG,
&Q931LoopbackRedirectHandle);
if (Status != STATUS_SUCCESS) {
Q931LoopbackRedirectHandle = NULL;
DebugError (Status, _T("Q931: Failed to create local dynamic redirect.\n"));
return (HRESULT)Status;
}
DebugF (_T("Q931: Connections traversing loopback interface to port %04X will be redirected to %08X:%04X.\n"),
Q931_TSAP_IP_TCP,
SOCKADDR_IN_PRINTF (&Q931ListenSocketAddress));
return (HRESULT) Status;
}
void
Q931StopLoopbackRedirect (
void
)
{
if (Q931LoopbackRedirectHandle) {
NatCancelDynamicRedirect (Q931LoopbackRedirectHandle);
Q931LoopbackRedirectHandle = NULL;
}
}