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Parsing HTTPSENDREQUESTEX'S LPINTERNET_BUFFERSA struct with Frida

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 This post is about how to read the LPINTERNET_BUFFERSA struct used by the Windows API HttpSendRequestExA. The background behind this post is answering an StackOverflow question but with a more detailed explanation. To perform this example, instead of writing an application I will use Internet Explorer and I will use FRIDA on it. That said, the definition of the struct used in HttpSendRequestExA/W is: typedef struct _INTERNET_BUFFERSA {      DWORD                     dwStructSize;      struct _INTERNET_BUFFERSA *Next;      LPCSTR                    lpcszHeader;      DWORD                     dwHeadersLength;      DWORD                     dwHeadersTotal;      LPVOID                    lpvBuffer;      DWORD                     dwBufferLength;      DWORD                     dwBufferTotal;      DWORD                     dwOffsetLow;      DWORD                     dwOffsetHigh; } INTERNET_BUFFERSA, *LPINTERNET_BUFFERSA; There are two things to note here, the first one is that the first mem