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SQLSERVER对加密的存储过程、视图、触发器进行解密(推荐)

程序员文章站 2022-05-09 08:10:41
加密测试的存储过程 if exists(select 1 from sysobjects where type='p' and name='p_test') drop...

加密测试的存储过程

if exists(select 1 from sysobjects where type='p' and name='p_test')
drop procedure p_test
go
create procedure p_test(@username varchar(20),@msg varchar(20) output)
with encryption
as
begin
  if(select count(1) from custs where name=@username)>0
    set @msg='此用户名存在'
  else
    set @msg='此用户名不存在'
end

解密的存储过程

create procedure decryption(@procedure sysname = null)
as
set nocount on
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'',16,10)
 /**//*'+replicate(cast('*'as nvarchar(max)), 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, @intprocspace, 1)) ^
(unicode(substring(@fake_01, @intprocspace, 1)) ^
unicode(substring(@fake_encrypt_01, @intprocspace, 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,
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, @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
go
启用dac
sp_configure 'remote admin connections';
go
----0:仅允许本地连接使用 dac,1:允许远程连接使用 dac
sp_configure 'remote admin connections', 0;
go
reconfigure with override;
go 

文件——>新建——>数据库引擎查询

服务器名称:admin:.或者admin:服务器名称

登录进去执行解密操作

use test
exec decryption p_test
go

SQLSERVER对加密的存储过程、视图、触发器进行解密(推荐)

为了安全起见,不要在正式环境进行解密,避免在解密过程中将原存储过程损坏!

总结

以上所述是小编给大家介绍的sqlserver对加密的存储过程、视图、触发器进行解密,希望对大家有所帮助