Windows NT 4.0 source code leak
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/*++
Copyright (c) 1996 Microsoft Corporation
Module Name:
accept.c
Abstract:
This module contains accept routines for the Winsock 2 to
Winsock 1.1 Mapper Service Provider.
The following routines are exported by this module:
WSPAccept()
Author:
Keith Moore (keithmo) 29-May-1996
Revision History:
--*/
#include "precomp.h"
#pragma hdrstop
SOCKET
WSPAPI
WSPAccept(
IN SOCKET s,
OUT struct sockaddr FAR * addr,
IN OUT LPINT addrlen,
IN LPCONDITIONPROC lpfnCondition,
IN DWORD dwCallbackData,
OUT LPINT lpErrno
)
/*++
Routine Description:
This routine extracts the first connection on the queue of pending
connections on s, and checks it against the condition function, provided
the condition function is specified (i.e., not NULL). The condition
function must be executed in the same thread as this routine is. If the
condition function returns CF_ACCEPT, this routine creates a new socket
and performs any socket grouping as indicated by the result parameter g
in the condition function . Newly created sockets have the same
properties as s including network events registered with WSPAsyncSelect()
or with WSPEventSelect(), but not including the listening socket's group
ID, if any.
If the condition function returns CF_REJECT, this routine rejects the
connection request. If the client's accept/reject decision cannot be made
immediately, the condition function will return CF_DEFER to indicate that
no decision has been made, and no action about this connection request is
to be taken by the service provider. When the client is ready to take
action on the connection request, it will invoke WSPAccept() again and
return either CF_ACCEPT or CF_REJECT as a return value from the condition
function.
For sockets which are in the (default) blocking mode, if no pending
connections are present on the queue, WSPAccept() blocks the caller until
a connection is present. For sockets in a non-blocking mode, if this
function is called when no pending connections are present on the queue,
WSPAccept() returns the error code WSAEWOULDBLOCK as described below. The
accepted socket may not be used to accept more connections. The original
socket remains open.
The argument addr is a result parameter that is filled in with the address
of the connecting entity, as known to the service provider. The exact
format of the addr parameter is determined by the address family in which
the communication is occurring. The addrlen is a value-result parameter;
it will initially contain the amount of space pointed to by addr. On
return, it must contain the actual length (in bytes) of the address
returned by the service provider. This call is used with connection-
oriented socket types such as SOCK_STREAM. If addr and/or addrlen are
equal to NULL, then no information about the remote address of the
accepted socket is returned. Otherwise, these two parameters shall be
filled in regardless of whether the condition function is specified or
what it returns.
The prototype of the condition function is as follows:
int
CALLBACK
ConditionFunc(
IN LPWSABUF lpCallerId,
IN LPWSABUF lpCallerData,
IN OUT LPQOS lpSQOS,
IN OUT LPQOS lpGQOS,
IN LPWSABUF lpCalleeId,
IN LPWSABUF lpCalleeData,
OUT GROUP FAR * g,
IN DWORD dwCallbackData
);
The lpCallerId and lpCallerData are value parameters which must
contain the address of the connecting entity and any user data
that was sent along with the connection request, respectively.
If no caller ID or caller data is available, the corresponding
parameter will be NULL.
lpSQOS references the flow specs for socket s specified by the
caller, one for each direction, followed by any additional
provider-specific parameters. The sending or receiving flow spec
values will be ignored as appropriate for any unidirectional
sockets. A NULL value for lpSQOS indicates no caller supplied
QOS. QOS information may be returned if a QOS negotiation is to
occur.
lpGQOS references the flow specs for the socket group the caller
is to create, one for each direction, followed by any additional
provider-specific parameters. A NULL value for lpGQOS indicates
no caller-supplied group QOS. QOS information may be returned if
a QOS negotiation is to occur.
The lpCalleeId is a value parameter which contains the local
address of the connected entity. The lpCalleeData is a result
parameter used by the condition function to supply user data back
to the connecting entity. The storage for this data must be
provided by the service provider. lpCalleeData->len initially
contains the length of the buffer allocated by the service
provider and pointed to by lpCalleeData->buf. A value of zero
means passing user data back to the caller is not supported. The
condition function will copy up to lpCalleeData->len bytes of
data into lpCalleeData->buf , and then update lpCalleeData->len
to indicate the actual number of bytes transferred. If no user
data is to be passed back to the caller, the condition function
will set lpCalleeData->len to zero. The format of all address and
user data is specific to the address family to which the socket
belongs.
The result parameter g is assigned within the condition function
to indicate the following actions:
if &g is an existing socket group ID, add s to this
group, provided all the requirements set by this group
are met; or
if &g = SG_UNCONSTRAINED_GROUP, create an unconstrained
socket group and have s as the first member; or
if &g = SG_CONSTRAINED_GROUP, create a constrained
socket group and have s as the first member; or
if &g = zero, no group operation is performed.
Any set of sockets grouped together must be implemented by a
single service provider. For unconstrained groups, any set of
sockets may be grouped together. A constrained socket group may
consist only of connection-oriented sockets, and requires that
connections on all grouped sockets be to the same address on the
same host. For newly created socket groups, the new group ID
must be available for the WinSock SPI client to retrieve by
calling WSPGetSockOpt() with option SO_GROUP_ID. A socket group
and its associated ID remain valid until the last socket
belonging to this socket group is closed. Socket group IDs are
unique across all processes for a given service provider.
dwCallbackData is supplied to the condition function exactly as
supplied by the caller of WSPAccept().
Arguments:
s - A descriptor identifying a socket which is listening for connections
after a WSPListen().
addr - An optional pointer to a buffer which receives the address of the
connecting entity, as known to the service provider. The exact
format of the addr argument is determined by the address family
established when the socket was created.
addrlen - An optional pointer to an integer which contains the length of
the address addr.
lpfnCondition - The procedure instance address of an optional, WinSock 2
client- supplied condition function which will make an accept/reject
decision based on the caller information passed in as parameters,
and optionally create and/or join a socket group by assigning an
appropriate value to the result parameter, g, of this routine.
dwCallbackData - Callback data to be passed back to the WinSock 2 client
as a condition function parameter. This parameter is not interpreted
by the service provider.
lpErrno - A pointer to the error code.
Return Value:
If no error occurs, WSPAccept() returns a value of type SOCKET which is
a descriptor for the accepted socket. Otherwise, a value of
INVALID_SOCKET is returned, and a specific error code is available
in lpErrno. Valid error codes are:
--*/
{
PSOCKET_INFORMATION socketInfo;
PSOCKET_INFORMATION socketInfo2;
SOCKET ws1Handle;
SOCKET ws2Handle;
INT err;
SOCK_ENTER( "WSPAccept", (PVOID)s, (PVOID)addr, (PVOID)addrlen, lpfnCondition );
SOCK_ASSERT( lpErrno != NULL );
err = SockEnterApi( TRUE, FALSE );
if( err != NO_ERROR ) {
SOCK_EXIT( "WSPAccept", INVALID_SOCKET, TRUE );
*lpErrno = err;
return INVALID_SOCKET;
}
//
// Setup locals so we know how to cleanup on exit.
//
socketInfo = NULL;
socketInfo2 = NULL;
ws1Handle = INVALID_SOCKET;
ws2Handle = INVALID_SOCKET;
//
// Attempt to find the socket in our lookup table.
//
socketInfo = SockFindAndReferenceWS2Socket( s );
if( socketInfo == NULL || socketInfo->State == SocketStateClosing ) {
IF_DEBUG(ACCEPT) {
SOCK_PRINT((
"WSPAccept failed on %s handle: %lx\n",
socketInfo == NULL ? "unknown" : "closed",
s
));
}
if( socketInfo != NULL ) {
SockDereferenceSocket( socketInfo );
}
SOCK_EXIT( "WSPAccept", INVALID_SOCKET, TRUE );
*lpErrno = WSAENOTSOCK;
return INVALID_SOCKET;
}
//
// Let the hooker do its thang.
//
SockPrepareForBlockingHook( socketInfo );
SockPreApiCallout();
ws1Handle = socketInfo->Hooker->accept(
socketInfo->WS1Handle,
addr,
addrlen
);
if( ws1Handle == INVALID_SOCKET ) {
err = socketInfo->Hooker->WSAGetLastError();
SOCK_ASSERT( err != NO_ERROR );
SockPostApiCallout();
goto exit;
}
SockPostApiCallout();
//
// Create a new socket to use for the connection.
//
socketInfo2 = SockCreateSocket(
socketInfo->Hooker,
socketInfo->AddressFamily,
socketInfo->SocketType,
socketInfo->Protocol,
socketInfo->CreationFlags,
socketInfo->CatalogEntryId,
ws1Handle,
&err
);
if( socketInfo2 == NULL ) {
SOCK_ASSERT( err != NO_ERROR );
goto exit;
}
SOCK_ASSERT( ws1Handle == socketInfo2->WS1Handle );
//
// Reference the hooker so it doesn't go away prematurely.
//
SockReferenceHooker( socketInfo->Hooker );
//
// Success!
//
SOCK_ASSERT( err == NO_ERROR );
ws2Handle = socketInfo2->WS2Handle;
SOCK_ASSERT( ws2Handle != INVALID_SOCKET );
exit:
if( err != NO_ERROR ) {
if( socketInfo2 != NULL ) {
SockDereferenceSocket( socketInfo2 );
SockDereferenceSocket( socketInfo2 );
}
if( ws1Handle != INVALID_SOCKET ) {
SockPreApiCallout();
socketInfo->Hooker->closesocket( ws1Handle );
SockPostApiCallout();
}
*lpErrno = err;
ws2Handle = INVALID_SOCKET;
}
SockDereferenceSocket( socketInfo );
SOCK_EXIT( "WSPAccept", ws2Handle, (BOOL)( ws2Handle == INVALID_SOCKET ) );
return ws2Handle;
} // WSPAccept