Oracle 透明数据加密（TDE）的常见任务

dingdingfish2023-09-23 15:21

环境准备

一个容器数据库，带一个PDB：orclpdb1。

目前没有进行任何加密设置。

sql 复制代码 
SQL> show pdbs;

    CON_ID CON_NAME                       OPEN MODE  RESTRICTED
---------- ------------------------------ ---------- ----------
         2 PDB$SEED                       READ ONLY  NO
         3 ORCLPDB1                       READ WRITE NO

SQL> show parameter wallet_root;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
wallet_root                          string

SQL> show parameter tde_configuration

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
tde_configuration                    string

配置Key Store

connect / as sysdba
ALTER SYSTEM SET wallet_root='$ORACLE_BASE/wallet' SCOPE=SPFILE;
shutdown immediate;
startup
!mkdir $ORACLE_BASE/wallet
ALTER SYSTEM SET tde_configuration="keystore_configuration=file"  SCOPE=BOTH;

目前位置，$ORACLE_BASE/wallet中还没有任何文件。

创建Key Store

sql 复制代码 
connect / as sysdba
ADMINISTER KEY MANAGEMENT CREATE KEYSTORE IDENTIFIED BY keypwd;

此时，key store文件有了：

bash 复制代码 
SQL> !ls $ORACLE_BASE/wallet
tde

SQL> !ls $ORACLE_BASE/wallet/tde
ewallet.p12

但key store的状态是关闭的：

sql 复制代码 
SQL> select con_id, status from V$ENCRYPTION_WALLET;

    CON_ID STATUS
---------- ------------------------------
         1 CLOSED
         2 CLOSED
         3 CLOSED

打开key store：

sql 复制代码 
ADMINISTER KEY MANAGEMENT SET KEYSTORE OPEN IDENTIFIED BY keypwd;

此时，根数据库的key store状态变成OPEN_NO_MASTER_KEY：

sql 复制代码 
SQL> select con_id, status from V$ENCRYPTION_WALLET;

    CON_ID STATUS
---------- ------------------------------
         1 OPEN_NO_MASTER_KEY
         2 CLOSED
         3 CLOSED

创建Master Key：

sql 复制代码 
ADMINISTER KEY MANAGEMENT SET KEY 
FORCE KEYSTORE
IDENTIFIED BY keypwd 
WITH BACKUP USING 'mekbkp';

我们可以看到备份，而且key store的状态变为：

sql 复制代码 
SQL> !ls $ORACLE_BASE/wallet/tde
ewallet_2023091407054383_mekbkp.p12  ewallet.p12

SQL> select con_id, status from V$ENCRYPTION_WALLET;

    CON_ID STATUS
---------- ------------------------------
         1 OPEN
         2 CLOSED
         3 CLOSED

当前系统表状态

Oracle 19c Advanced Security Guide 文档列出了TDE相关的系统表。我们大致看一下。

V$ENCRYPTION_WALLET和key store相关：

sql 复制代码 
SQL>
set lines 120
col status for a10
select CON_ID, WRL_TYPE, STATUS, WALLET_TYPE, WALLET_ORDER, KEYSTORE_MODE from V$ENCRYPTION_WALLET;

    CON_ID WRL_TYPE             STATUS     WALLET_TYPE          WALLET_OR KEYSTORE
---------- -------------------- ---------- -------------------- --------- --------
         1 FILE                 OPEN       PASSWORD             SINGLE    NONE
         2 FILE                 CLOSED     UNKNOWN              SINGLE    UNITED
         3 FILE                 CLOSED     UNKNOWN              SINGLE    UNITED

V$DATABASE_KEY_INFO与系统表空间加密有关：

sql 复制代码 
SQL> select * from V$DATABASE_KEY_INFO;

ENCRYPT ENCRYPTEDKEY
------- ------------------------------------------------------------------------------------------------
MASTERKEYID                      MAS     CON_ID
-------------------------------- --- ----------
AES128  77B4410C25AFD59E983669101DE55EB20000000000000000000000000000000000000000000000000000000000000000
24F4F8FE12434F18BF88049E85E70C82 YES          1

NONE    000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000 NO           2

NONE    000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000 NO           3

V$ENCRYPTION_KEYS和master key有关：

sql 复制代码 
col creation_time for a20
col activation_time for a20
col creator_pdbname for a12
col origin for a10
alter session set nls_date_format = 'MM/DD/YYYY HH24:MI';
select cast(creation_time as date) as creation_time, cast(activation_time as date) as activation_time , key_use, keystore_type, origin, backed_up, creator_pdbname from V$ENCRYPTION_KEYS;

CREATION_TIME        ACTIVATION_TIME      KEY_USE    KEYSTORE_TYPE     ORIGIN     BACKED_UP CREATOR_PDBN
-------------------- -------------------- ---------- ----------------- ---------- --------- ------------
09/14/2023 07:05     09/14/2023 07:05     TDE IN PDB SOFTWARE KEYSTORE LOCAL      NO        CDB$ROOT

加解密PDB中的表空间

连接到PDB。

sql 复制代码 
SQL> connect sys@orclpdb1 as sysdba
Enter password:
Connected.

目前PDB中还没有master key，因此无法加密：

sql 复制代码 
SQL> alter tablespace users encryption online encrypt;
alter tablespace users encryption online encrypt
*
ERROR at line 1:
ORA-28361: master key not yet set

SQL> select status from V$ENCRYPTION_WALLET;

STATUS
----------
CLOSED

设置PDB中的master key：

sql 复制代码 
ADMINISTER KEY MANAGEMENT SET KEYSTORE OPEN IDENTIFIED BY keypwd;
ADMINISTER KEY MANAGEMENT SET KEY IDENTIFIED BY keypwd WITH BACKUP USING 'pdbmekbkp';

现在PDB的master key已经设置好：

sql 复制代码 
SQL> select status from V$ENCRYPTION_WALLET;

STATUS
------------------------------
OPEN

SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 16
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 08:42 ewallet.p12

现在加解密都没有问题了：

sql 复制代码 
-- 在线加密
SQL> alter tablespace users encryption online encrypt;

Tablespace altered.

SQL> alter tablespace users encryption online decrypt;

Tablespace altered.

-- 离线加密
SQL> alter tablespace users offline;

Tablespace altered.

SQL> alter tablespace users encryption offline encrypt;

Tablespace altered.

SQL> alter tablespace users online;

Tablespace altered.

当前系统表状态

以下SQL语句均在CDB$ROOT中执行。

V$ENCRYPTION_WALLET和key store相关，其中PDB相关的行变化了：

sql 复制代码 
SQL>
set lines 120
col status for a10
select CON_ID, WRL_TYPE, STATUS, WALLET_TYPE, WALLET_ORDER, KEYSTORE_MODE from V$ENCRYPTION_WALLET;

    CON_ID WRL_TYPE             STATUS     WALLET_TYPE          WALLET_OR KEYSTORE
---------- -------------------- ---------- -------------------- --------- --------
         1 FILE                 OPEN       PASSWORD             SINGLE    NONE
         2 FILE                 CLOSED     UNKNOWN              SINGLE    UNITED
         3 FILE                 OPEN       PASSWORD             SINGLE    UNITED

V$DATABASE_KEY_INFO与系统表空间加密有关，也是和PDB相关的行变化了：

sql 复制代码 
SQL> select * from V$DATABASE_KEY_INFO;

ENCRYPT ENCRYPTEDKEY
------- ------------------------------------------------------------------------------------------------
MASTERKEYID                      MAS     CON_ID
-------------------------------- --- ----------
AES128  77B4410C25AFD59E983669101DE55EB20000000000000000000000000000000000000000000000000000000000000000
24F4F8FE12434F18BF88049E85E70C82 YES          1

NONE    000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
00000000000000000000000000000000 NO           2

AES128  69A8A389784AFCD06F84FE3EB12F3E8A0000000000000000000000000000000000000000000000000000000000000000
64D9F54F8A354F36BFECB3955CDD77DA YES          3

V$ENCRYPTION_KEYS和master key有关：

sql 复制代码 
col creation_time for a20
col activation_time for a20
col creator_pdbname for a12
col origin for a10
alter session set nls_date_format = 'MM/DD/YYYY HH24:MI';
select cast(creation_time as date) as creation_time, cast(activation_time as date) as activation_time , key_use, keystore_type, origin, backed_up, creator_pdbname from V$ENCRYPTION_KEYS;

CREATION_TIME        ACTIVATION_TIME      KEY_USE    KEYSTORE_TYPE     ORIGIN     BACKED_UP CREATOR_PDBN
-------------------- -------------------- ---------- ----------------- ---------- --------- ------------
09/14/2023 07:05     09/14/2023 07:05     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       CDB$ROOT
09/14/2023 08:42     09/14/2023 08:42     TDE IN PDB SOFTWARE KEYSTORE LOCAL      NO        ORCLPDB1

以下SQL语句均在PDB中执行：

sql 复制代码 
SQL> select encrypted from user_tablespaces where tablespace_name = 'USERS';

ENC
---
YES

SQL> select TS#, ENCRYPTIONALG, ENCRYPTEDTS, STATUS, CON_ID from V$ENCRYPTED_TABLESPACES;

       TS# ENCRYPT ENC STATUS         CON_ID
---------- ------- --- ---------- ----------
         5 AES128  YES NORMAL              3

Key Store改为自动登录

目前表空间可以加解密，但有一个问题。即如果数据库重启，我们还需要手工打开Key Store。

sql 复制代码 
connect / as sysdba
ADMINISTER KEY MANAGEMENT CREATE 
AUTO_LOGIN KEYSTORE FROM KEYSTORE
IDENTIFIED BY keypwd;

现在Key Store的WALLET_TYPE由PASSWORD变为AUTOLOGIN：

sql 复制代码 
set lines 120
col status for a10
select CON_ID, WRL_TYPE, STATUS, WALLET_TYPE, WALLET_ORDER, KEYSTORE_MODE from V$ENCRYPTION_WALLET;


    CON_ID WRL_TYPE             STATUS     WALLET_TYPE          WALLET_OR KEYSTORE
---------- -------------------- ---------- -------------------- --------- --------
         1 FILE                 OPEN       AUTOLOGIN            SINGLE    NONE
         2 FILE                 OPEN       AUTOLOGIN            SINGLE    UNITED
         3 FILE                 OPEN       AUTOLOGIN            SINGLE    UNITED

重启数据库后，Key Store状态自动变为打开：

sql 复制代码 
SQL> select status from V$ENCRYPTION_WALLET;

STATUS
----------
OPEN
OPEN
OPEN

SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 24
-rw-------. 1 oracle oinstall 5512 Sep 14 08:59 cwallet.sso
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 08:42 ewallet.p12

自动登录的Key Store文件为cwallet.sso。

备份Key Store

此操作需在CDB$ROOT中进行，否则报错：

sql 复制代码 
SQL> ADMINISTER KEY MANAGEMENT BACKUP KEYSTORE USING 'bkp230914' IDENTIFIED BY keypwd;
ADMINISTER KEY MANAGEMENT BACKUP KEYSTORE USING 'bkp230914' IDENTIFIED BY keypwd
*
ERROR at line 1:
ORA-65040: operation not allowed from within a pluggable database

必须用FORCE KEYSTORE子句：

sql 复制代码 
SQL> ADMINISTER KEY MANAGEMENT BACKUP KEYSTORE USING 'bkp230914' IDENTIFIED BY keypwd;
ADMINISTER KEY MANAGEMENT BACKUP KEYSTORE USING 'bkp230914' IDENTIFIED BY keypwd
*
ERROR at line 1:
ORA-28417: password-based keystore is not open


SQL> ADMINISTER KEY MANAGEMENT BACKUP KEYSTORE USING 'bkp230914' FORCE KEYSTORE IDENTIFIED BY keypwd;

keystore altered.

查看生成的备份文件，看来在tag中加入日期是多此一举：

sql 复制代码 
SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 32
-rw-------. 1 oracle oinstall 5512 Sep 14 09:04 cwallet.sso
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:04 ewallet_2023091409040585_bkp230914.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:04 ewallet.p12

也可以备份到指定位置：

sql 复制代码 
SQL> connect / as sysdba;
Connected.
SQL> ADMINISTER KEY MANAGEMENT BACKUP KEYSTORE USING 'bkp230914' FORCE KEYSTORE IDENTIFIED BY keypwd to '/tmp';

keystore altered.

SQL> !ls /tmp/*bkp*
/tmp/ewallet_2023091402173955_bkp230914.p12

修改Wallet类型为Local Auto Login

当前类型为Auto Login，但Local Auto Login更安全，因为只能在本机使用。

sql 复制代码 
SQL> select WALLET_TYPE from V$ENCRYPTION_WALLET;

WALLET_TYPE
--------------------
AUTOLOGIN

过程：

sql 复制代码 
-- 关闭key store
SQL> administer key management set keystore close;
keystore altered.

SQL> show parameter wallet_root

NAME                                 TYPE        VALUE
------------------------------------ ----------- ----------------------------------
wallet_root                          string      /u01/app/oracle/admin/ORCL/wallet

-- 必须将原有的auto login key store移走，否则后续建立时报错
-- ORA-46630: keystore cannot be created at the specified location
SQL> !cd /u01/app/oracle/admin/ORCL/wallet
SQL> !mv cwallet.sso cwallet.sso.bak

SQL> administer key management set keystore open force keystore identified by keypwd;
keystore altered.

SQL> administer key management create local auto_login keystore from keystore identified by keypwd;
keystore altered.

修改Key Store的口令

修改口令可以不备份，但必须使用FORCE KEYSTORE打开Key Store：

sql 复制代码 
connect / as sysdba

ADMINISTER KEY MANAGEMENT ALTER KEYSTORE PASSWORD 
FORCE KEYSTORE
IDENTIFIED BY
keypwd 
SET newkeypwd;

修改口令不影响加解密操作。

不知为何，修改口令时，第一次不要求备份，而第二次要求：

sql 复制代码 
ADMINISTER KEY MANAGEMENT ALTER KEYSTORE PASSWORD
FORCE KEYSTORE
IDENTIFIED BY
newkeypwd
  5  SET keypwd;
ADMINISTER KEY MANAGEMENT ALTER KEYSTORE PASSWORD
*
ERROR at line 1:
ORA-46631: keystore needs to be backed up

SQL>
ADMINISTER KEY MANAGEMENT ALTER KEYSTORE PASSWORD 
FORCE KEYSTORE
IDENTIFIED BY
newkeypwd 
SET keypwd
WITH BACKUP USING 'chgpwd';

SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 40
-rw-------. 1 oracle oinstall 5512 Sep 14 09:20 cwallet.sso
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:04 ewallet_2023091409040585_bkp230914.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:20 ewallet_2023091409204262_chgpwd.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:20 ewallet.p12

Master Key的 Rekey（轮换）

Rekey操作会新建一个master key，并激活他。

CDB$ROOT和PDB有各自的Master Key，本例仅针对PDB。

sql 复制代码 
SQL> alter session set container=orclpdb1;
Session altered.

col creation_time for a20
col activation_time for a20
col creator_pdbname for a12
col origin for a10
alter session set nls_date_format = 'MM/DD/YYYY HH24:MI';
select cast(creation_time as date) as creation_time, cast(activation_time as date) as activation_time , key_use, keystore_type, origin, backed_up, creator_pdbname from V$ENCRYPTION_KEYS;

CREATION_TIME        ACTIVATION_TIME      KEY_USE    KEYSTORE_TYPE     ORIGIN     BACKED_UP CREATOR_PDBN
-------------------- -------------------- ---------- ----------------- ---------- --------- ------------
09/14/2023 08:42     09/14/2023 08:42     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       ORCLPDB1

执行rekey操作：

sql 复制代码 
ADMINISTER KEY MANAGEMENT 
SET ENCRYPTION KEY
FORCE KEYSTORE
IDENTIFIED BY keypwd
WITH BACKUP USING 'mekrekey';

keystore altered.

SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 48
-rw-------. 1 oracle oinstall 6776 Sep 14 09:28 cwallet.sso
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:04 ewallet_2023091409040585_bkp230914.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:20 ewallet_2023091409204262_chgpwd.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:28 ewallet_2023091409281769_mekrekey.p12
-rw-------. 1 oracle oinstall 6731 Sep 14 09:28 ewallet.p12

此时，V$ENCRYPTION_KEYS表新增了一条记录：

sql 复制代码 
CREATION_TIME        ACTIVATION_TIME      KEY_USE    KEYSTORE_TYPE     ORIGIN     BACKED_UP CREATOR_PDBN
-------------------- -------------------- ---------- ----------------- ---------- --------- ------------
09/14/2023 08:42     09/14/2023 08:42     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       ORCLPDB1
09/14/2023 09:28     09/14/2023 09:28     TDE IN PDB SOFTWARE KEYSTORE LOCAL      NO        ORCLPDB1

很容易猜到，ACTIVATION_TIME最新，BACKED_UP为NO的应该就是当前的Master Key。

加密Key的Rekey

本例也是针对PDB。

Master Key的rekey不会重新解密和加密数据，但DEK（Data Encryption Key）的rekey会。

表空间加密使用alter tablespace，表加密则使用alter table。本例为前者，并使用在线的rekey：

sql 复制代码 
SQL> alter tablespace users encryption rekey;

Tablespace altered.

Elapsed: 00:01:23.42

创建和激活Master Key

这个分两步进行的操作实际就是Rekey的过程。

虽然也可以针对CDB$ROOT，但本例针对PDB。

sql 复制代码 
SQL>
ADMINISTER KEY MANAGEMENT CREATE KEY 
USING TAG 'newmek'
FORCE KEYSTORE
IDENTIFIED BY keypwd
WITH BACKUP USING 'newmek';

SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 60
-rw-------. 1 oracle oinstall 8216 Sep 14 09:58 cwallet.sso
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:04 ewallet_2023091409040585_bkp230914.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:20 ewallet_2023091409204262_chgpwd.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:28 ewallet_2023091409281769_mekrekey.p12
-rw-------. 1 oracle oinstall 6731 Sep 14 09:58 ewallet_2023091409580241_newmek.p12
-rw-------. 1 oracle oinstall 8171 Sep 14 09:58 ewallet.p12

可以，看到此Master Key并没有激活（ACTIVATION_TIME为空）：

sql 复制代码 
CREATION_TIME        ACTIVATION_TIME      KEY_USE    KEYSTORE_TYPE     ORIGIN     BACKED_UP CREATOR_PDBN
-------------------- -------------------- ---------- ----------------- ---------- --------- ------------
09/14/2023 09:28     09/14/2023 09:28     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       ORCLPDB1
09/14/2023 08:42     09/14/2023 08:42     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       ORCLPDB1
09/14/2023 09:58                          TDE IN PDB SOFTWARE KEYSTORE LOCAL      NO        ORCLPDB1

激活Master Key：

sql 复制代码 
SQL> select key_id from V$ENCRYPTION_KEYS where ACTIVATION_TIME is null;

KEY_ID
------------------------------------------------------------------------------
AYgYXF7JY08WvylfJIZ44LUAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

SQL>
ADMINISTER KEY MANAGEMENT USE KEY
'AYgYXF7JY08WvylfJIZ44LUAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
FORCE KEYSTORE
IDENTIFIED BY keypwd
WITH BACKUP USING 'newmek';

keystore altered.

SQL> !ls -l1 $ORACLE_BASE/wallet/tde
total 68
-rw-------. 1 oracle oinstall 8216 Sep 14 10:11 cwallet.sso
-rw-------. 1 oracle oinstall 2555 Sep 14 07:05 ewallet_2023091407054383_mekbkp.p12
-rw-------. 1 oracle oinstall 3995 Sep 14 08:42 ewallet_2023091408425331_pdbmekbkp.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:04 ewallet_2023091409040585_bkp230914.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:20 ewallet_2023091409204262_chgpwd.p12
-rw-------. 1 oracle oinstall 5467 Sep 14 09:28 ewallet_2023091409281769_mekrekey.p12
-rw-------. 1 oracle oinstall 6731 Sep 14 09:58 ewallet_2023091409580241_newmek.p12
-rw-------. 1 oracle oinstall 8171 Sep 14 10:11 ewallet_2023091410112509_newmek.p12
-rw-------. 1 oracle oinstall 8171 Sep 14 10:11 ewallet.p12

系统表中的状态变了。

sql 复制代码 
CREATION_TIME        ACTIVATION_TIME      KEY_USE    KEYSTORE_TYPE     ORIGIN     BACKED_UP CREATOR_PDBN
-------------------- -------------------- ---------- ----------------- ---------- --------- ------------
09/14/2023 09:28     09/14/2023 09:28     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       ORCLPDB1
09/14/2023 08:42     09/14/2023 08:42     TDE IN PDB SOFTWARE KEYSTORE LOCAL      YES       ORCLPDB1
09/14/2023 09:58     09/14/2023 10:11     TDE IN PDB SOFTWARE KEYSTORE LOCAL      NO        ORCLPDB1

参考

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