create procedure decryptobject (@objectname varchar(50))
with encryption as
begin
declare @objectname1 varchar(100)
declare @sql1 nvarchar(4000),@sql2 nvarchar(4000),@sql3 nvarchar(4000),@sql4 nvarchar(4000),@sql5 nvarchar(4000),@sql6 nvarchar(4000),@sql7 nvarchar(4000),@sql8 nvarchar(4000),@sql9 nvarchar(4000),@sql10 nvarchar(4000)
declare @origsptext1 nvarchar(4000), @origsptext2 nvarchar(4000) , @origsptext3 nvarchar(4000), @resultsp nvarchar(4000)
declare @i int , @t bigint
declare @m int,@n int,@q int
declare @tablename varchar(255) --触发器所对应的表名
declare @trigtype varchar(6) --触发器类型
declare @type char(1) --对象类型：p-procedure ;v-view; t-trigger
declare @bb bit
select @i=count(1) from sysobjects where name = @objectname
if @i=0
begin
print 'object ' + @objectname + ' isnt exist!'--对象不存在
return
end
select @type= case xtype when 'tr' then 't' else xtype end from sysobjects where name = @objectname
if (@type<>'t' and @type<>'v' and @type<>'p')
begin
print 'object ' + @objectname + ' isnt procedure or trigger or view!'--没有所需要的对象类型
return
end
select @bb=encrypted from syscomments where id = object_id(@objectname)
select @m=max(colid) from syscomments where id = object_id(@objectname)
if @bb=0
begin
print 'object ' + @objectname + ' is not encrypted!'--对象没有加密
return
end
create table #temp(colid int,ctext varbinary(8000))
create table #tempresult(cctext nvarchar(4000))
insert #temp select colid,ctext from syscomments where id = object_id(@objectname)--get encrypted data 将加密信息存储于临时表中
if @type='t'--如果是触发子,则取得它的表名和类型
begin
set @tablename=(select sysobjects_1.name from dbo.sysobjects inner join dbo.sysobjects sysobjects_1 on dbo.sysobjects.parent_obj = sysobjects_1.id where (dbo.sysobjects.type = 'tr') and (dbo.sysobjects.name = @objectname))
set @trigtype=(select case when dbo.sysobjects.deltrig > 0 then 'delete' when dbo.sysobjects.instrig > 0 then 'insert' when dbo.sysobjects.updtrig > 0 then 'update' end from dbo.sysobjects inner join dbo.sysobjects sysobjects_1 on dbo.sysobjects.parent_obj = sysobjects_1.id where (dbo.sysobjects.type = 'tr') and (dbo.sysobjects.name = @objectname))
end
set @sql1=case @type--为修改原有的对象内容准备alter语句
when 'p' then 'alter procedure '+ @objectname +' with encryption as '
when 'v' then 'alter view '+ @objectname +' with encryption as select dbo.dtproperties.* from dbo.dtproperties'
when 't' then 'alter trigger '[email protected]+' on '+ @tablename+' with encryption for '[email protected]+' as print ''a'''
end
set @q=len(@sql1)
set @[email protected] +replicate('-',[email protected])
select @sql2=replicate('-',4000),@sql3=replicate('-',4000),@sql4=replicate('-',4000),@sql5=replicate('-',4000),@sql6=replicate('-',4000),@sql7=replicate('-',4000),@sql8=replicate('-',4000),@sql9=replicate('-',4000),@sql10=replicate('-',4000)
exec(@[email protected][email protected][email protected][email protected][email protected][email protected][email protected][email protected][email protected])
select @sql1='',@sql2='',@sql3='',@sql4='',@sql5='',@sql6='',@sql7='',@sql8='',@sql9='',@sql10=''
set @n=1 --从编号为1开始
while @n<[email protected]
begin
set @origsptext1=(select ctext from #temp where [email protected])--从临时表中取加密数据
set @origsptext3=(select ctext from syscomments where id=object_id(@objectname) and [email protected])--从修改过的对象取得对象数据
if @n=1--如果是第一次循环,则需要准备前面的开头部分的语句
begin
set @origsptext2=case @type
when 'p' then 'create procedure '+ @objectname +' with encryption as '
when 'v' then 'create view '+ @objectname +' with encryption as select dbo.dtproperties.* from dbo.dtproperties'
when 't' then 'create trigger '[email protected]+' on '+ @tablename+' with encryption for '[email protected]+' as print ''a'''
end
set @q=4000-len(@origsptext2)
set @[email protected]+replicate('-',@q)
end
else
begin
set @origsptext2=replicate('-', 4000)
end
set @i=1
set @resultsp = replicate(n'a', (datalength(@origsptext1) / 2))--fill temporary variable
while @i<=datalength(@origsptext1)/2
begin
--reverse encryption (xor original+bogus+bogus encrypted)
set @resultsp = stuff(@resultsp, @i, 1, nchar(
unicode(substring(@origsptext1, @i, 1)) ^
(
unicode(substring(@origsptext2, @i, 1)) ^ unicode(substring(@origsptext3, @i, 1))
)
)
)
set @[email protected]+1
end
if @n=1 begin set @[email protected] end
if @n=2 begin set @[email protected] end
if @n=3 begin set @[email protected] end
if @n=4 begin set @[email protected] end
if @n=5 begin set @[email protected] end
if @n=6 begin set @[email protected] end
if @n=7 begin set @[email protected] end
if @n=8 begin set @[email protected] end
if @n=9 begin set @[email protected] end
if @n=10 begin set @[email protected] end
insert into #tempresult values (@resultsp)--把解密数据放入结果表中
set @[email protected]+1--循环
end
drop table #temp--删除临时表
set @resultsp=case @type
when 'p' then 'drop procedure '+ @objectname
when 'v' then 'drop view '+ @objectname
when 't' then 'drop trigger '[email protected]
end
execute( @resultsp)--删除对象
--重新创建对象
if @n=1 begin exec(@sql1) end
if @n=2 begin exec(@sql1 + @sql2) end
if @n=3 begin exec(@sql1 + @[email protected] ) end
if @n=4 begin exec(@sql1 + @[email protected] + @sql4 ) end
if @n=5 begin exec(@sql1 + @[email protected] + @sql4 + @sql5) end
if @n=6 begin exec(@sql1 + @[email protected] + @sql4 + @sql5+ @sql6) end
if @n=7 begin exec(@sql1 + @[email protected] + @sql4 + @sql5+ @sql6+ @sql7 ) end
if @n=8 begin exec(@sql1 + @[email protected] + @sql4 + @sql5+ @sql6+ @sql7 + @sql8) end
if @n=9 begin exec(@sql1 + @[email protected] + @sql4 + @sql5+ @sql6+ @sql7 + @sql8 + @sql9) end
if @n=10 begin exec(@sql1 + @[email protected] + @sql4 + @sql5+ @sql6+ @sql7 + @sql8 + @sql8 + @sql10) end
select * from #tempresult--显示结果表
drop table #tempresult--删除结果表
end
--nchar 根据 unicode 标准所进行的定义，用给定整数代码返回 unicode 字符。
--语法 nchar ( integer_expression )
--参数
--integer_expression 介于 0 与 65535 之间的所有正整数。如果指定了超出此范围的值，将返回 null。
---------------------------------
--stuff 删除指定长度的字符并在指定的起始点插入另一组字符。
--语法 stuff ( character_expression , start , length , character_expression )
--参数
--character_expression 由字符数据组成的表达式。character_expression 可以是常量、变量，也可以是字符或二进制数据的列。
--start 是一个整形值，指定删除和插入的开始位置。如果 start 或 length 是负数，则返回空字符串。如果 start 比第一个 character_expression 长，则返回空字符串。
--length 是一个整数，指定要删除的字符数。如果 length 比第一个 character_expression 长，则最多删除到最后一个 character_expression 中的最后一个字符。
