Function alloc_mem

src/alloc_mem/va_syscall.rs:16–50

(size: usize)

) -> i32;

pub unsafe fn alloc_mem(size: usize) -> Result<*mut u8, String> {
    let mut base_address: *mut c_void = ptr::null_mut();
    let mut region_size: usize = size;

    const MEM_COMMIT: u32 = 0x0000_1000;
    const MEM_RESERVE: u32 = 0x0000_2000;
    const PAGE_EXECUTE_READWRITE: u32 = 0x40;

    // Indirect syscall via DInvoke: dynamically build and execute the syscall stub.
    let function_type: NtAllocateVirtualMemory;
    #[allow(unused_assignments)]
    let mut status: Option<i32> = None;

    // NtAllocateVirtualMemory(ProcessHandle = GetCurrentProcess())
    dinvoke::execute_syscall!(
        "NtAllocateVirtualMemory",
        function_type,
        status,
        HANDLE(-1isize as isize),          // ProcessHandle
        &mut base_address,                 // BaseAddress
        0,                                 // ZeroBits
        &mut region_size,                  // RegionSize
        MEM_COMMIT | MEM_RESERVE,          // AllocationType
        PAGE_EXECUTE_READWRITE,            // Protect
    );

    if status == Some(0) { // STATUS_SUCCESS
        Ok(base_address as *mut u8)
    } else {
        Err(match status {
            Some(code) => format!("NtAllocateVirtualMemory failed with status: 0x{:x}", code),
            None => "NtAllocateVirtualMemory syscall execution failed".to_string(),
        })
    }
}