一 什么是DAC
sql Server 2005 为管理员提供了一种特殊的诊断连接,以供在无法与服务器建立标准连接时使用。即使在 sql Server 不响应标准连接请求时,管理员也可以使用这种连接访问 sql Server,以便执行诊断查询并解决问题。命令行界面 (sqlcmd) 通过使用特殊的管理员开关 (-A),提供并支持这种专用管理员连接 (DAC)。
二如何使用DAC登录到服务器
1 本机DAC登录
命令行方式下执行 sqlcmd -A -S sql服务器名
2 远程DAC登录
1) 打开远程DAC选项
'程序'->'sql Server2005'-> '配置工具'-> 'sql Server 外围应用配置器'-> '功能的外围应用配置器'-> 'DataBase Engine'-> 'DAC' -> '启用远程DAC'
2) 登录到远程服务器
sqlcmd -A -S 192.168.0.1 -U sa -P 123456
3 登录后,可以通过查询动态管理视图来诊断问题 1.使用 DAC 与服务器连接
在 sql Server Management Stu@R_502_410@ 中,不打开其他 DAC,单击工具栏上的“数据库引擎查询”。
在“连接到数据库引擎”对话框的“服务器名称”框中,键入 ADMIN:,并在其后继续键入服务器实例的名称。例如,若要连接到名为 ACCT\PAYABLE 的服务器实例,请键入 ADMIN:ACCT\PAYABLE。
完成“身份验证”部分(提供 sysadmin 组成员的凭据),然后单击“连接”。将建立连接。 2.DAC设置可以连接, 0 - 指明仅允许本地连接使用 DAC
1 - 指明允许远程连接使用 DAC
sp_configure 'remote admin connections',1;
GO
RECONFIGURE;
GO 在STU@R_502_410@ DAC模试下执行或在sqlcmd -A -o c:\1.txt模式下执行,输出文件
代码如下:
DECLARE @return_value int EXEC @return_value = [dbo].[sp_undecrypt]
@procedure = testencry,
@revfl = 0 SELECT 'Return Value' = @return_value GO
@procedure = testencry,
@revfl = 0 SELECT 'Return Value' = @return_value GO
解密存储过程如下:
代码如下:
1 Create PROCEDURE [dbo].[sp_undecrypt]
2 (@procedure sysname = NULL,@revfl int = 1)
3 AS
4 /**//*
5 王成辉翻译整理,转贴请注明出自微软BI开拓者www.windbi.com
6 调用形式为:
7 exec dbo.sp__windbi$decrypt @procedure,0
8 如果第二个参数使用1的话,会给出该存储过程的一些提示。
9 --版本4.0 修正存储过程过长解密出来是空白的问题
*/
SET NOCOUNT ON
IF @revfl = 1
BEGIN
PRINT '警告:该存储过程会删除并重建原始的存储过程。'
PRINT ' 在运行该存储过程之前确保你的数据库有一个备份。'
PRINT ' 该存储过程通常应该运行在产品环境的一个备份的非产品环境下。'
PRINT ' 为了运行这个存储过程,将参数@refl的值更改为0。'
RETURN 0
END
DECLARE @intProcSpace bigint,@t bigint,@maxColID smallint,@procNameLength int
select @maxColID = max(subobjid) FROM
sys.sysobjvalues WHERE objid = object_id(@procedure)
--select @maxColID as 'Rows in sys.sysobjvalues'
select @procNameLength = datalength(@procedure) + 29
DECLARE @real_01 nvarchar(max)
DECLARE @fake_01 nvarchar(max)
DECLARE @fake_encrypt_01 nvarchar(max)
DECLARE @real_decrypt_01 nvarchar(max),@real_decrypt_01a nvarchar(max)
declare @objtype varchar(2),@ParentName nvarchar(max)
select @real_decrypt_01a = ''
--提取对象的类型如是存储过程还是函数,如果是触发器,还要得到其父对象的名称
select @objtype=type,@parentname=object_name(parent_object_id)
from sys.objects where [object_id]=object_id(@procedure)
-- 从sys.sysobjvalues里提出加密的imageval记录
SET @real_01=(SELECT top 1 imageval FROM sys.sysobjvalues WHERE objid =
object_id(@procedure) and valclass = 1 order by subobjid) --创建一个临时表
create table #output ( [ident] [int] IDENTITY (1,1) NOT NULL,
[real_decrypt] NVARCHAR(MAX) )
--开始一个事务,稍后回滚
BEGIN TRAN
--更改原始的存储过程,用短横线替换
if @objtype='P'
SET @fake_01='ALTER PROCEDURE '+ @procedure +' WITH ENCRYPTION AS select 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='FN'
SET @fake_01='ALTER FUNCTION '+ @procedure +'() RETURNS INT WITH ENCRYPTION AS BEGIN RETURN 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/ END'
else if @objtype='V'
SET @fake_01='ALTER view '+ @procedure +' WITH ENCRYPTION AS select 1 as col
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='TR'
SET @fake_01='ALTER trigger '+ @procedure +' ON '+@parentname+'WITH ENCRYPTION AFTER INSERT AS RAISERROR (''N'',16,10)
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
EXECUTE (@fake_01)
--从sys.sysobjvalues里提出加密的假的
SET @fake_encrypt_01=(SELECT top 1 imageval FROM sys.sysobjvalues WHERE objid =
object_id(@procedure) and valclass = 1 order by subobjid )
if @objtype='P'
SET @fake_01='Create PROCEDURE '+ @procedure +' WITH ENCRYPTION AS select 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='FN'
SET @fake_01='CREATE FUNCTION '+ @procedure +'() RETURNS INT WITH ENCRYPTION AS BEGIN RETURN 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/ END'
else if @objtype='V'
SET @fake_01='Create view '+ @procedure +' WITH ENCRYPTION AS select 1 as col
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='TR'
SET @fake_01='Create trigger '+ @procedure +' ON '+@parentname+'WITH ENCRYPTION AFTER INSERT AS RAISERROR (''N'',datalength(@real_01) /2 - @procNameLength)+'*/'
--开始计数
SET @intProcSpace=1
--使用字符填充临时变量
SET @real_decrypt_01 = replicate(cast('A'as nvarchar(max)),(datalength(@real_01) /2 ))
--循环设置每一个变量,创建真正的变量
--每次一个字节
SET @intProcSpace=1
--如有必要,遍历每个@real_xx变量并解密
WHILE @intProcSpace<=(datalength(@real_01)/2)
BEGIN
--真的和假的和加密的假的进行异或处理
SET @real_decrypt_01 = stuff(@real_decrypt_01,@intProcSpace,1,
NCHAR(UNICODE(substring(@real_01,1)) ^
(UNICODE(substring(@fake_01,1)) ^
UNICODE(substring(@fake_encrypt_01,1)))))
SET @intProcSpace=@intProcSpace+1
END
--通过sp_helptext逻辑向表#output里插入变量
insert #output (real_decrypt) select @real_decrypt_01
--select real_decrypt AS '#output chek' from #output --测试
-- -------------------------------------
--开始从sp_helptext提取
-- -------------------------------------
declare @dbname sysname
,@BlankSpaceAdded int
,@BasePos int
,@CurrentPos int
,@TextLength int
,@LineId int
,@AddOnLen int
,@LFCR int --回车换行的长度
,@DefinedLength int
,@SyscomText nvarchar(max)
,@Line nvarchar(255)
Select @DefinedLength = 255
SELECT @BlankSpaceAdded = 0 --跟踪行结束的空格。注意Len函数忽略了多余的空格
CREATE TABLE #CommentText
(LineId int
,Text nvarchar(255) collate database_default)
--使用#output代替sys.sysobjvalues
DECLARE ms_crs_syscom CURSOR LOCAL
FOR SELECT real_decrypt from #output
ORDER BY ident
FOR READ ONLY
--获取文本
SELECT @LFCR = 2
SELECT @LineId = 1
OPEN ms_crs_syscom
FETCH NEXT FROM ms_crs_syscom into @SyscomText
WHILE @@fetch_status >= 0
BEGIN
SELECT @BasePos = 1
SELECT @CurrentPos = 1
SELECT @TextLength = LEN(@SyscomText)
WHILE @CurrentPos != 0
BEGIN
--通过回车查找行的结束
SELECT @CurrentPos = CHARINDEX(char(13)+char(10),@SyscomText,
@BasePos)
--如果找到回车
IF @CurrentPos != 0
BEGIN
--如果@Lines的长度的新值比设置的大就插入@Lines目前的内容并继续
While (isnull(LEN(@Line),0) + @BlankSpaceAdded +
@CurrentPos-@BasePos + @LFCR) > @DefinedLength
BEGIN
SELECT @AddOnLen = @DefinedLength-(isnull(LEN(@Line),0) +
@BlankSpaceAdded)
INSERT #CommentText VALUES
( @LineId,
isnull(@Line,N'') + isnull(SUBSTRING(@SyscomText,
@BasePos,@AddOnLen),N''))
SELECT @Line = NULL,@LineId = @LineId + 1,
@BasePos = @BasePos + @AddOnLen,@BlankSpaceAdded = 0
END
SELECT @Line = isnull(@Line,N'') +
isnull(SUBSTRING(@SyscomText,@BasePos,@CurrentPos-@BasePos + @LFCR),N'')
SELECT @BasePos = @CurrentPos+2
INSERT #CommentText VALUES( @LineId,@Line )
SELECT @LineId = @LineId + 1
SELECT @Line = NULL
END
ELSE
--如果回车没找到
BEGIN
IF @BasePos <= @TextLength
BEGIN
--如果@Lines长度的新值大于定义的长度
While (isnull(LEN(@Line),0) + @BlankSpaceAdded +
@TextLength-@BasePos+1 ) > @DefinedLength
BEGIN
SELECT @AddOnLen = @DefinedLength -
(isnull(LEN(@Line),0) + @BlankSpaceAdded)
INSERT #CommentText VALUES
( @LineId,@BlankSpaceAdded =
0
END
SELECT @Line = isnull(@Line,@TextLength-@BasePos+1 ),N'')
if LEN(@Line) < @DefinedLength and charindex(' ',
@SyscomText,@TextLength+1 ) > 0
BEGIN
SELECT @Line = @Line + ' ',@BlankSpaceAdded = 1
END
END
END
END
FETCH NEXT FROM ms_crs_syscom into @SyscomText
END
IF @Line is NOT NULL
INSERT #CommentText VALUES( @LineId,@Line )
select Text from #CommentText order by LineId
CLOSE ms_crs_syscom
DEALLOCATE ms_crs_syscom
DROP TABLE #CommentText
-- -------------------------------------
--结束从sp_helptext提取
-- -------------------------------------
--删除用短横线创建的存储过程并重建原始的存储过程
ROLLBACK TRAN
DROP TABLE #output
2 (@procedure sysname = NULL,@revfl int = 1)
3 AS
4 /**//*
5 王成辉翻译整理,转贴请注明出自微软BI开拓者www.windbi.com
6 调用形式为:
7 exec dbo.sp__windbi$decrypt @procedure,0
8 如果第二个参数使用1的话,会给出该存储过程的一些提示。
9 --版本4.0 修正存储过程过长解密出来是空白的问题
*/
SET NOCOUNT ON
IF @revfl = 1
BEGIN
PRINT '警告:该存储过程会删除并重建原始的存储过程。'
PRINT ' 在运行该存储过程之前确保你的数据库有一个备份。'
PRINT ' 该存储过程通常应该运行在产品环境的一个备份的非产品环境下。'
PRINT ' 为了运行这个存储过程,将参数@refl的值更改为0。'
RETURN 0
END
DECLARE @intProcSpace bigint,@t bigint,@maxColID smallint,@procNameLength int
select @maxColID = max(subobjid) FROM
sys.sysobjvalues WHERE objid = object_id(@procedure)
--select @maxColID as 'Rows in sys.sysobjvalues'
select @procNameLength = datalength(@procedure) + 29
DECLARE @real_01 nvarchar(max)
DECLARE @fake_01 nvarchar(max)
DECLARE @fake_encrypt_01 nvarchar(max)
DECLARE @real_decrypt_01 nvarchar(max),@real_decrypt_01a nvarchar(max)
declare @objtype varchar(2),@ParentName nvarchar(max)
select @real_decrypt_01a = ''
--提取对象的类型如是存储过程还是函数,如果是触发器,还要得到其父对象的名称
select @objtype=type,@parentname=object_name(parent_object_id)
from sys.objects where [object_id]=object_id(@procedure)
-- 从sys.sysobjvalues里提出加密的imageval记录
SET @real_01=(SELECT top 1 imageval FROM sys.sysobjvalues WHERE objid =
object_id(@procedure) and valclass = 1 order by subobjid) --创建一个临时表
create table #output ( [ident] [int] IDENTITY (1,1) NOT NULL,
[real_decrypt] NVARCHAR(MAX) )
--开始一个事务,稍后回滚
BEGIN TRAN
--更改原始的存储过程,用短横线替换
if @objtype='P'
SET @fake_01='ALTER PROCEDURE '+ @procedure +' WITH ENCRYPTION AS select 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='FN'
SET @fake_01='ALTER FUNCTION '+ @procedure +'() RETURNS INT WITH ENCRYPTION AS BEGIN RETURN 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/ END'
else if @objtype='V'
SET @fake_01='ALTER view '+ @procedure +' WITH ENCRYPTION AS select 1 as col
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='TR'
SET @fake_01='ALTER trigger '+ @procedure +' ON '+@parentname+'WITH ENCRYPTION AFTER INSERT AS RAISERROR (''N'',16,10)
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
EXECUTE (@fake_01)
--从sys.sysobjvalues里提出加密的假的
SET @fake_encrypt_01=(SELECT top 1 imageval FROM sys.sysobjvalues WHERE objid =
object_id(@procedure) and valclass = 1 order by subobjid )
if @objtype='P'
SET @fake_01='Create PROCEDURE '+ @procedure +' WITH ENCRYPTION AS select 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='FN'
SET @fake_01='CREATE FUNCTION '+ @procedure +'() RETURNS INT WITH ENCRYPTION AS BEGIN RETURN 1
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/ END'
else if @objtype='V'
SET @fake_01='Create view '+ @procedure +' WITH ENCRYPTION AS select 1 as col
/**//*'+REPLICATE(cast('*'as nvarchar(max)),datalength(@real_01) /2 - @procNameLength)+'*/'
else if @objtype='TR'
SET @fake_01='Create trigger '+ @procedure +' ON '+@parentname+'WITH ENCRYPTION AFTER INSERT AS RAISERROR (''N'',datalength(@real_01) /2 - @procNameLength)+'*/'
--开始计数
SET @intProcSpace=1
--使用字符填充临时变量
SET @real_decrypt_01 = replicate(cast('A'as nvarchar(max)),(datalength(@real_01) /2 ))
--循环设置每一个变量,创建真正的变量
--每次一个字节
SET @intProcSpace=1
--如有必要,遍历每个@real_xx变量并解密
WHILE @intProcSpace<=(datalength(@real_01)/2)
BEGIN
--真的和假的和加密的假的进行异或处理
SET @real_decrypt_01 = stuff(@real_decrypt_01,@intProcSpace,1,
NCHAR(UNICODE(substring(@real_01,1)) ^
(UNICODE(substring(@fake_01,1)) ^
UNICODE(substring(@fake_encrypt_01,1)))))
SET @intProcSpace=@intProcSpace+1
END
--通过sp_helptext逻辑向表#output里插入变量
insert #output (real_decrypt) select @real_decrypt_01
--select real_decrypt AS '#output chek' from #output --测试
-- -------------------------------------
--开始从sp_helptext提取
-- -------------------------------------
declare @dbname sysname
,@BlankSpaceAdded int
,@BasePos int
,@CurrentPos int
,@TextLength int
,@LineId int
,@AddOnLen int
,@LFCR int --回车换行的长度
,@DefinedLength int
,@SyscomText nvarchar(max)
,@Line nvarchar(255)
Select @DefinedLength = 255
SELECT @BlankSpaceAdded = 0 --跟踪行结束的空格。注意Len函数忽略了多余的空格
CREATE TABLE #CommentText
(LineId int
,Text nvarchar(255) collate database_default)
--使用#output代替sys.sysobjvalues
DECLARE ms_crs_syscom CURSOR LOCAL
FOR SELECT real_decrypt from #output
ORDER BY ident
FOR READ ONLY
--获取文本
SELECT @LFCR = 2
SELECT @LineId = 1
OPEN ms_crs_syscom
FETCH NEXT FROM ms_crs_syscom into @SyscomText
WHILE @@fetch_status >= 0
BEGIN
SELECT @BasePos = 1
SELECT @CurrentPos = 1
SELECT @TextLength = LEN(@SyscomText)
WHILE @CurrentPos != 0
BEGIN
--通过回车查找行的结束
SELECT @CurrentPos = CHARINDEX(char(13)+char(10),@SyscomText,
@BasePos)
--如果找到回车
IF @CurrentPos != 0
BEGIN
--如果@Lines的长度的新值比设置的大就插入@Lines目前的内容并继续
While (isnull(LEN(@Line),0) + @BlankSpaceAdded +
@CurrentPos-@BasePos + @LFCR) > @DefinedLength
BEGIN
SELECT @AddOnLen = @DefinedLength-(isnull(LEN(@Line),0) +
@BlankSpaceAdded)
INSERT #CommentText VALUES
( @LineId,
isnull(@Line,N'') + isnull(SUBSTRING(@SyscomText,
@BasePos,@AddOnLen),N''))
SELECT @Line = NULL,@LineId = @LineId + 1,
@BasePos = @BasePos + @AddOnLen,@BlankSpaceAdded = 0
END
SELECT @Line = isnull(@Line,N'') +
isnull(SUBSTRING(@SyscomText,@BasePos,@CurrentPos-@BasePos + @LFCR),N'')
SELECT @BasePos = @CurrentPos+2
INSERT #CommentText VALUES( @LineId,@Line )
SELECT @LineId = @LineId + 1
SELECT @Line = NULL
END
ELSE
--如果回车没找到
BEGIN
IF @BasePos <= @TextLength
BEGIN
--如果@Lines长度的新值大于定义的长度
While (isnull(LEN(@Line),0) + @BlankSpaceAdded +
@TextLength-@BasePos+1 ) > @DefinedLength
BEGIN
SELECT @AddOnLen = @DefinedLength -
(isnull(LEN(@Line),0) + @BlankSpaceAdded)
INSERT #CommentText VALUES
( @LineId,@BlankSpaceAdded =
0
END
SELECT @Line = isnull(@Line,@TextLength-@BasePos+1 ),N'')
if LEN(@Line) < @DefinedLength and charindex(' ',
@SyscomText,@TextLength+1 ) > 0
BEGIN
SELECT @Line = @Line + ' ',@BlankSpaceAdded = 1
END
END
END
END
FETCH NEXT FROM ms_crs_syscom into @SyscomText
END
IF @Line is NOT NULL
INSERT #CommentText VALUES( @LineId,@Line )
select Text from #CommentText order by LineId
CLOSE ms_crs_syscom
DEALLOCATE ms_crs_syscom
DROP TABLE #CommentText
-- -------------------------------------
--结束从sp_helptext提取
-- -------------------------------------
--删除用短横线创建的存储过程并重建原始的存储过程
ROLLBACK TRAN
DROP TABLE #output