ReadProcessMemory.cpp

/*
*	Module Name:
*		ReadProcessMemory.cpp
*
*	Abstract:
*		Reads a blob of memory from the specified process.
*
*	Author:
*		Nemanja (Nemi) Mulasmajic <nm@triplefault.io>
*			http://triplefault.io
*/
#pragma warning(disable: 4710)

#pragma warning(push, 0)
#include <Windows.h>
#include <stdio.h>
#pragma warning(pop)

/* 
*	The entry point.
*/
int main(int argc, char** argv)
{
	int status = -1;

	PCHAR LocalBuffer = NULL;
	HANDLE RemoteProcess = NULL;

	// Check for the right number of parameters passed in to this application.
	if (argc != 4)
	{
		printf(	"usage: app.exe [PID] [Address] [Size]\n"
				"\t-> \"%s\" 1337 0xDEADBEEF 100\n", argv[0]);

		goto Cleanup;
	}

	// Convert the argument strings to numbers.
	DWORD RemoteProcessId = strtoul(argv[1], NULL, 0);
	ULONG_PTR RemoteAddress = (ULONG_PTR)strtoull(argv[2], NULL, 0);
	DWORD BufferSize = strtoul(argv[3], NULL, 0);

	// Try to open the remote process with the ability to read virtual memory.
	RemoteProcess = OpenProcess(PROCESS_VM_READ, FALSE, RemoteProcessId);
	if (!RemoteProcess)
	{
		fprintf(stderr, "[-] ERROR: Couldn't open process %lu. OpenProcess failed with error: %lu.\n", RemoteProcessId, GetLastError());
		goto Cleanup;
	}

	// Create a place to store the bytes we're going to read from the target process.
	LocalBuffer = (PCHAR)malloc(BufferSize);
	if (!LocalBuffer)
	{
		fprintf(stderr, "[-] ERROR: Failed to allocate %lu bytes for memory read.\n", BufferSize);
		goto Cleanup;
	}

	SIZE_T BytesRead = 0;

	// Read the bytes from the remote process and store it in our local buffer.
	if (!ReadProcessMemory(RemoteProcess, (PVOID)RemoteAddress, LocalBuffer, BufferSize, &BytesRead) ||  BytesRead != BufferSize)
	{
		fprintf(stderr, "[-] ERROR: Failed to read %lu bytes from 0x%p in process %lu. ReadProcessMemory failed error: %lu.\n", BufferSize, (PVOID)RemoteAddress, RemoteProcessId, GetLastError());
		goto Cleanup;
	}
	
	printf("[+] Success: Read %lu bytes from 0x%p in process %lu.\n", BufferSize, (PVOID)RemoteAddress, RemoteProcessId);

	status = 0;

Cleanup:

	// Free allocated memory.
	if (LocalBuffer)
	{
		free(LocalBuffer);
		LocalBuffer = NULL;
	}

	// Close handle.
	if (RemoteProcess)
	{
		CloseHandle(RemoteProcess);
		RemoteProcess = NULL;
	}

	// Wait for [ENTER] key press to terminate the program.
	getchar();

	return status;
}