驱动挂载物理页代码示例
使用的实验环境为32位xp系统在101012分页模式下
此实验用于测试对分页模式的掌握程度
代码思路如下:
- 获取目标进程的cr3
- 在目标进程中申请新的物理页
- 拆分新申请的物理页的线性地址
- 通过差分出的内容获取pte
- 将pte写入到要挂载的线性地址的pte中(这个线性地址也可以为不同cr3中的线性地址,这种情况下就可以两个进程共享同一物理页但是要把pte和pde都挂载好)
- 此时目标线性地址和新申请的线性地址映射为同一物理页
样例代码:
#include <ntddk.h>
#define NTSTRSAFE_LIB
#include <ntstrsafe.h>
#include <intrin.h>VOID Unload(PDRIVER_OBJECT pDriver) {KdPrint(("unload"));}NTSTATUS DriverEntry(PDRIVER_OBJECT pDriver, PUNICODE_STRING pRegPath) {NTSTATUS status = STATUS_SUCCESS;pDriver->DriverUnload = Unload;KdPrint(("begin"));//417 01 00 17DWORD32 new_va = 0x417000;DWORD32 new_cr3 = 0x02e96000;DWORD32 old_cr3 = 0x0;DWORD32* pdt_va = (DWORD32*)0xc0300000;UCHAR* ptt_va = (UCHAR*)0xc0000000;//拆分new_vaKdPrint(("开始拆分线性地址"));DWORD32 new_va_10_1 = new_va >> 0x16;DWORD32 new_va_10_2 = new_va << 0xa;new_va_10_2 >>= 0x16;DWORD32 new_va_12 = new_va && 0x00000fff;KdPrint(("10:0x%x, 10:0x%x, 12:0x%x \r\n", new_va_10_1, new_va_10_2, new_va_12));//挂载物理页KdPrint(("开始挂载物理页"));KIRQL irql = KeRaiseIrqlToDpcLevel();old_cr3 = __readcr3();__writecr3(new_cr3);KeLowerIrql(irql);DWORD32* pte = (ptt_va + ((new_va_10_1 << 12) + (new_va_10_2 << 2)));KdPrint(("0x%p\r\n",pte));DWORD32* new_pte = (DWORD32*)(ptt_va + 4);KdPrint(("0x%p\r\n", new_pte));*new_pte = *pte;irql = KeRaiseIrqlToDpcLevel();__writecr3(old_cr3);KeLowerIrql(irql);/*DWORD32* cr3_va = (DWORD32*)0xc0300000;for (size_t i = 0; i < 1024; i++){KdPrint(("%d: 0x%x", i, cr3_va[i]));}*/return status;
}