Existe uma maneira rápida de localizar todas as colunas no SQL Server 2008 R2 que são criptografadas/têm dados criptografados?

Supondo que você esteja falando sobre dados criptografados com chaves do SQL Server, existe uma maneira de encontrar essas colunas.

A Key_name()função retornará o nome da chave usada para a criptografia para esse valor específico e retornará NULL se não houver nada criptografado com uma chave "conhecida" (de terceiros ou simples não criptografada).

Com esse conhecimento podemos testar cada coluna para ver se contém pelo menos uma linha que tenha um valor varbinary que retorne um nome de chave

funcionalidade de key_name()

--create a test database
CREATE DATABASE [Test_ENCR]
GO

--change context
USE [Test_ENCR]
GO


--because it's possible to encrypt different rows with different keys I'll create 2 keys for this demo
-- Create a symmetric key
CREATE SYMMETRIC KEY symmetricKey1
   WITH ALGORITHM = AES_128
   ENCRYPTION BY PASSWORD = 'password01!';
GO

-- Create a second key
CREATE SYMMETRIC KEY symmetricKey2 
   WITH ALGORITHM = AES_128
   ENCRYPTION BY PASSWORD = 'password02!';
GO



--create a table that will have a column holding:
--1: encrypted row with key1
--2: encrypted row with key2
--3: a non encrypted just varbinary value

CREATE TABLE encryptedTable
(ID int IDENTITY PRIMARY KEY,
EncryptedCol varbinary(256) NOT NULL);
GO


-- open key1
OPEN SYMMETRIC KEY symmetricKey1 
    DECRYPTION BY PASSWORD = 'password01!';
GO

-- open key2
OPEN SYMMETRIC KEY symmetricKey2 
    DECRYPTION BY PASSWORD = 'password02!';
GO

--insert encrypted data with key1
INSERT INTO encryptedTable(encryptedCol)
VALUES ( ENCRYPTBYKEY (Key_GUID('symmetricKey1'), 'EncryptedText1'));
GO

--insert encrypted data with key2
INSERT INTO encryptedTable(encryptedCol)
VALUES ( ENCRYPTBYKEY (Key_GUID('symmetricKey2'), 'EncryptedText2'));
GO


--insert just varbinary data
INSERT INTO encryptedTable(encryptedCol)
VALUES (CONVERT(varbinary(256),'NotEncryptedTextJustVarBinary'))



--have a look, without the key, all varbinary for you.
SELECT * FROM encryptedTable
GO

resultados:

--Return all key_names
SELECT DISTINCT     key_name(encryptedcol), 
                    EncryptedCol 
FROM encryptedTable;

resultados:

Como implementá-lo para encontrar colunas criptografadas

--How do we dynamically find all the columns that have at least one row with a encrypted value?

-- first we will find all tables and column with a varbinary datatype
-- then we will test all those columns with a simple select
-- If the key_name() function returns a value, the column and table name are stored together with the keyname

--create a table to hold all varbinary columns and tables
CREATE TABLE #TablesWithVarbinCols (    ID int IDENTITY,
                                TableName nvarchar(128),
                                ColumnName nvarchar(128)
                                );

--create a table to hold the end result
CREATE TABLE #TablesWithEncryption (
                                TableName nvarchar(128),
                                ColumnName nvarchar(128),
                                KeyName varchar(128)
                                );


--find and store all table and column names of user tables containing a varbinary column
INSERT INTO #TablesWithVarbinCols (TableName,ColumnName)
SELECT      o.[name] as TableName,
            c.[name] as ColumnName
FROM        sys.objects o
INNER JOIN  sys.columns c
ON          o.[object_id]=c.[object_id] 
INNER JOIN  sys.types t
ON          c.system_type_id=t.system_type_id
WHERE       o.[type]='U'
AND         t.name=N'varbinary'
AND         c.max_length > -1;


DECLARE @col nvarchar(256)
DECLARE @tab nvarchar(256)
DECLARE @c int = 1
DECLARE @MaxC int
DECLARE @SQL varchar(max)

SELECT @MaxC=MAX(ID)
FROM #TablesWithVarbinCols

--loop the previous result and create a simple select statement with a key_name() is not null where clause. 
--If you have a result, store the details
WHILE @c <= @MaxC
BEGIN
    SELECT  @Tab=TableName,
         @col=ColumnName
    FROM    #TablesWithVarbinCols
    WHERE   ID=@c

    SET @SQL='  INSERT INTO #TablesWithEncryption (TableName, ColumnName, KeyName)
                SELECT DISTINCT '''+@Tab +''',''' +@col +''', key_name('+@Col +') from '+ @tab +' 
                WHERE key_name('+@Col +') is not null;'
    exec (@SQL)

    DELETE
    FROM #TablesWithVarbinCols
    WHERE id=@c;
    SET @c=@c+1
END

--select the result
SELECT * FROM #TablesWithEncryption;

resultados:

--cleanup
DROP TABLE #TablesWithVarbinCols;
DROP TABLE #TablesWithEncryption;

O problema com a criptografia no nível da célula é que a coluna em si não é realmente criptografada, são os dados contidos nessa coluna. As próprias colunas são apenas colunas varbinárias (porque é isso que é necessário) e podem conter dados completamente legíveis. É o uso das funções ENCRYPTBY*e DECRYPTBY*que realmente tornam os dados criptografados.

Você pode começar simplesmente consultando a exibição sys.columns para todas as colunas que são varbinárias:

select
  object_name(a.object_id) [objectname]
  ,a.name [columnname]
  ,a.column_id
from
   sys.columns a
   join sys.types b on (a.system_type_id = b.system_type_id)
where
   b.name = N'varbinary';

Caso contrário, você precisará revisar seu código para identificar onde as funções de criptografia/descriptografia estão sendo usadas:

select
   object_name(object_id) [objectname]
   ,definition
from
   sys.sql_modules
where
   definition like N'%ENCRYPT%' 
   OR definition like N'%DECRYPT%';

Execute a consulta abaixo em um banco de dados específico

select 
    t.name as [Table],
    c.name as [Column], 
    c.encryption_type_desc
from   
    sys.all_columns c inner join
    sys.tables t on c.object_id = t.object_id
where  
    c.encryption_type is not null 
order by
    t.name,
    c.name

Ligeiramente alterado de

https://social.msdn.microsoft.com/Forums/sqlserver/en-US/ca9d8360-5d7e-4de1-abe6-ce1afda595a9/how-to-find-which-table-columns-are-encrypted?forum=sqlsecurity

Você pode localizar as colunas criptografadas com keys\certificates pesquisando todas as colunas varbinary e verificando uma chave de criptografia com a função KEY_NAME.

No entanto, este processo é um pouco caro e demorado. Se você precisar localizar essas colunas regularmente, sugiro "marcar" as colunas com propriedades estendidas. Podemos desenvolver a solução de Edward Dortland e "marcar" as colunas encontradas com propriedades estendidas como criptografado, encryptkey e encryptcert.

--create a table to hold all varbinary columns and tables
CREATE TABLE #TablesWithVarbinCols (    ID int IDENTITY,
                            SchemaName nvarchar(128),
                            TableName nvarchar(128),
                            ColumnName nvarchar(128)
                            );

--find and store all table and column names of user tables containing a 
varbinary column
INSERT INTO #TablesWithVarbinCols (SchemaName,TableName,ColumnName)
SELECT      s.[name] as SchemaName,
            o.[name] as TableName,
            c.[name] as ColumnName
FROM        sys.objects o
INNER JOIN  sys.schemas s
ON          s.[schema_id] = o.[schema_id]
INNER JOIN  sys.columns c
ON          o.[object_id]=c.[object_id] 
INNER JOIN  sys.types t
ON          c.system_type_id=t.system_type_id
WHERE       o.[type]='U'
AND         t.name=N'varbinary'
AND         c.max_length > -1;

DECLARE @sch nvarchar(128)
DECLARE @col nvarchar(256)
DECLARE @tab nvarchar(256)
DECLARE @key nvarchar(256)
DECLARE @cert nvarchar(256)
DECLARE @c int = 1
DECLARE @MaxC int
DECLARE @SQL nvarchar(max)

SELECT @MaxC=MAX(ID)
FROM #TablesWithVarbinCols

--loop the previous result and create a simple select statement with a 
key_name() is not null where clause. 
--If you have a result, store the details
WHILE @c <= @MaxC
BEGIN
    SET @key = NULL;
    SELECT  @sch=SchemaName,
            @Tab=TableName,
            @col=ColumnName
    FROM    #TablesWithVarbinCols
    WHERE   ID=@c


SET @SQL='SELECT DISTINCT @key= key_name('+@Col +') from '+ @tab +' 
            WHERE key_name('+@Col +') is not null;'


exec sp_executesql @SQL, N'@key nvarchar(256) out', @key out

SELECT @cert =  c.name 
from sys.symmetric_keys sk
join sys.key_encryptions ke
    on
    sk.symmetric_key_id= ke.key_id
join sys.certificates c
    on
    ke.thumbprint=c.thumbprint
where sk.name = @key


IF (@key IS NOT NULL)
BEGIN

    SET @SQL=
    'EXEC sp_addextendedproperty @name = N''encrypted'', @value = N''1'', '+
    '@level0type = N''Schema'', @level0name = '''+@Sch+''', '+
    '@level1type = N''Table'', @level1name = '''+@tab+''','+
    '@level2type = N''Column'', @level2name = '''+@col+'''
    '

    EXEC sp_executesql @SQL

    SET @SQL=
    'EXEC sp_addextendedproperty @name = N''encryptkey'', @value = '''+@key+''', '+
    '@level0type = N''Schema'', @level0name = '''+@Sch+''', '+
    '@level1type = N''Table'', @level1name = '''+@tab+''','+
    '@level2type = N''Column'', @level2name = '''+@col+'''
    '

    EXEC sp_executesql @SQL

    SET @SQL=
    'EXEC sp_addextendedproperty @name = N''encryptcert'', @value = '''+@cert+''', '+
    '@level0type = N''Schema'', @level0name = '''+@Sch+''', '+
    '@level1type = N''Table'', @level1name = '''+@tab+''','+
    '@level2type = N''Column'', @level2name = '''+@col+'''
    '

    EXEC sp_executesql @SQL

END

DELETE
FROM #TablesWithVarbinCols
WHERE id=@c;
SET @c=@c+1

END

drop table #TablesWithVarbinCols

Em seguida, podemos encontrar facilmente as colunas criptografadas pesquisando as propriedades estendidas.

--Adjust WHERE clause depending on what tags you are looking for
SELECT
   SCHEMA_NAME(tbl.schema_id) AS SchemaName,    
   tbl.name AS TableName, 
   clmns.name AS ColumnName,
  p.name AS ExtendedPropertyName,    --remove for programming
   CAST(p.value AS sql_variant) AS ExtendedPropertyValue
FROM
   sys.tables AS tbl
   INNER JOIN sys.all_columns AS clmns ON clmns.object_id=tbl.object_id
   INNER JOIN sys.extended_properties AS p ON p.major_id=tbl.object_id AND p.minor_id=clmns.column_id AND p.class=1
WHERE p.name in ('encrypted','encryptkey','encryptcert')