奇怪的結果從DecryptByPassphrase

Question

我想加密和解密表中的一列。我的代碼是這樣的：

drop table EncryptString 
go 
create table EncryptString(db int, String varchar(100)) 
go 
insert into EncryptString values (2, '123456789') 
go 
ALTER TABLE EncryptString 
ADD StringEncrypted varbinary(256); 
GO 

declare @Pass nvarchar(512) 
set @Pass = 'somepassword' 
update EncryptString set StringEncrypted = ENCRYPTBYPASSPHRASE(@Pass, String, 1,     convert(varbinary(128), db)) 
where db = 2 

select * From EncryptString 

SELECT db, StringEncrypted 
AS 'Encrypted String', CONVERT(nvarchar, 
DecryptByPassphrase('somepassword', StringEncrypted, 1 
, CONVERT(varbinary, db))) 
AS 'Decrypted String' FROM EncryptString 
WHERE db = 2; 

爲什麼我的 '解密的字符串' 是這樣的： ㈱㐳㘵㠷9

感謝

Answer 1

您加密varchar但隨後從轉換爲nvarchar解密時的二進制varchar表示。

即有效，你正在做的SELECT CAST(CAST('123456789' AS VARBINARY(30)) AS NVARCHAR(30))

如果你改變了解密位CONVERT(varchar它按預期工作。如果需要，您可以從varchar轉換爲nvarchar。