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Sixth LSP Tip

Windows Winsock was build upon the concepts of BSD sockets, but Microsoft extended the API to support Windows specific socket operation, one neglected group of functions are the Winsock 2 extension function which you can get via WSAIoctlwith the SIO_GET_EXTENSION_FUNCTION_POINTER parameter. Some applications and services are using the extended functions to work with Winsock, and unless you intercept them as well, some applications will slip through.

A good example would be IIs and Squid, both are system services that are using the method AcceptEx, and if you need to intercept the accept function then you probably will need to intercept AcceptEx to cover all applications. Same logic goes to connect and ConnetEx.