• HOME
• PRODUCTS
• DOWNLOADS
• LSP GUIDE
• CONTACT
• ABOUT

---

Retail products

---

Traffic interception SDK

Control every TCP/IP network connection

• Route connections via proxy
• Redirect connections and modify the data
• Block connections and applications

Learn More

SSL interception SDK

View SSL in plaintext and modify it

• View the SSL stream decrypted in plaintext
• Redirect SSL connection and modify decrypted data
• Browser shows "SSL lock" without warnings

Learn More

---

Documentation

---

extension.cpp Go to the documentation of this file. // THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF // ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO // THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A // PARTICULAR PURPOSE. // // Copyright (C) 2004 Microsoft Corporation. All Rights Reserved. // // Module Name: extension.cpp // // Description: // // This sample illustrates an IFS based LSP which implements basic proxying // capabilities. // // This file contains all of the Winsock extension functions that the LSP needs // to intercept in order to proxy connections. In terms of Winsock extension // functions this means only the ConnectEx function needs to be intercepted. // #include "lspdef.h" // // Function: LoadExtensionFunction // // Description: // This function dynamically loads the given extension function from the // underlying provider. Each extension function checks to see if the // corresponding extension function for the lower provider is loaded // before calling. If not, it will load it as needed. This is necessary // if the app loads the extension function for say TCP and then calls // that extension function on a UDP socket. Normally this isn't the case // but we're being defensive here. // BOOL LoadExtensionFunction( FARPROC **func, GUID ExtensionGuid, LPWSPIOCTL fnIoctl, SOCKET s ) { DWORD dwBytes; int rc, error; // Use the lower provider's WSPIoctl to load the extension function rc = fnIoctl( s, SIO_GET_EXTENSION_FUNCTION_POINTER, &ExtensionGuid, sizeof(GUID), func, sizeof(FARPROC), &dwBytes, NULL, NULL, NULL, &error ); if ( SOCKET_ERROR == rc ) { dbgprint("LoadExtensionFunction: WSAIoctl (SIO_GET_EXTENSION_FUNCTION) failed: %d", error); return FALSE; } else { return TRUE; } } // // Function: ExtConnectEx // // Description: // This is our provider's ConnectEx function. When an app calls WSAIoctl // to request the function pointer to ConnectEx, we intercept the call // and return a pointer to our extension function instead. This ConnectEx // implementation needs to perform the same proxying check that WSPConnect // does. // BOOL PASCAL FAR ExtConnectEx( IN SOCKET s, IN const struct sockaddr FAR *name, IN int namelen, IN PVOID lpSendBuffer OPTIONAL, IN DWORD dwSendDataLength, OUT LPDWORD lpdwBytesSent, IN LPOVERLAPPED lpOverlapped ) { SOCKET_CONTEXT *sockContext = NULL; SOCKADDR *proxyAddr = NULL; int Errno = NO_ERROR, proxyLen = 0, rc = FALSE; sockContext = FindSocketContext( s ); if ( NULL == sockContext ) { dbgprint("ExtConnectEx: FindSocketContext failed!"); Errno = WSAENOTSOCK; goto cleanup; } // Make sure we already have the extension function if ( NULL == sockContext->Provider->NextProcTableExt.lpfnConnectEx ) { GUID guidConnectEx = WSAID_CONNECTEX; rc = LoadExtensionFunction( (FARPROC **)&sockContext->Provider->NextProcTableExt.lpfnConnectEx, guidConnectEx, sockContext->Provider->NextProcTable.lpWSPIoctl, s ); if ( FALSE == rc ) { dbgprint("Next proc table ConnectEx == NULL!"); Errno = WSAEFAULT; goto cleanup; } } // See if the connect needs to be proxied FindDestinationAddress( sockContext, name, namelen, &proxyAddr, &proxyLen ); rc = sockContext->Provider->NextProcTableExt.lpfnConnectEx( s, proxyAddr, proxyLen, lpSendBuffer, dwSendDataLength, lpdwBytesSent, lpOverlapped ); cleanup: return rc; }

Copyright © 2009 Komodia Inc. All rights reserved

Home | Portfolio | Services | Articles | Blog