MDEV-8409: Changing file-key-management-encryption-algorithm causes crash and no real info why
Analysis: Both bugs has two different error cases. Firstly, at startup
when server reads latest checkpoint but requested key_version,
key management plugin or encryption algorithm or method is not found
leading corrupted log entry. Secondly, similarly when reading system
tablespace if requested key_version, key management plugin or encryption
algorithm or method is not found leading buffer pool page corruption.
Fix: Firsly, when reading checkpoint at startup check if the log record
may be encrypted and if we find that it could be encrypted, print error
message and do not start server. Secondly, if page is buffer pool seems
corrupted but we find out that there is crypt_info, print additional
error message before asserting.
Added new dynamic configuration variable innodb_buf_dump_status_frequency
to configure how often buffer pool dump status is printed in the logs.
A number between [0, 100] that tells how oftern buffer pool dump status
in percentages should be printed. E.g. 10 means that buffer pool dump
status is printed when every 10% of number of buffer pool pages are
dumped. Default is 0 (only start and end status is printed).
Analysis: Problem is that both encrypted tables and compressed tables use
FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION to store
required metadata. Furhermore, for only compressed tables currently
code skips compression.
Fixes:
- Only encrypted pages store key_version to FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION,
no need to fix
- Only compressed pages store compression algorithm to FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION,
no need to fix as they have different page type FIL_PAGE_PAGE_COMPRESSED
- Compressed and encrypted pages now use a new page type FIL_PAGE_PAGE_COMPRESSED_ENCRYPTED and
key_version is stored on FIL header offset FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION and compression
method is stored after FIL header similar way as compressed size, so that first
FIL_PAGE_COMPRESSED_SIZE is stored followed by FIL_PAGE_COMPRESSION_METHOD
- Fix buf_page_encrypt_before_write function to really compress pages if compression is enabled
- Fix buf_page_decrypt_after_read function to really decompress pages if compression is used
- Small style fixes
This is an addendum to the fix for MDEV-7026. The ARM memory model is
similar to that of PowerPC and thus needs the same semantics with
respect to memory barriers. That is, os_atomic_test_and_set_*_release()
must be a store with a release barrier followed by a full
barrier. Unlike x86 using __sync_lock_test_and_set() which is
implemented as “exclusive load with acquire barriers + exclusive store”
is insufficient in contexts where os_atomic_test_and_set_*_release()
macros are used.
Analysis: Problem was that we did try to read from tablespace
that was being dropped.
Fixed by introducing a new function to find a tablespace only
if it is not being dropped currently and adding this check
before trying to read pages from tablespace.
Analysis: At fil_spage_get_space there is small change that space
is found from tablespace list but we have not yet created node
for it (and added it to space->chain) and as we hold fil_system
mutex here fil_node_create can't continue.
Fixed by allowing UT_LIST_GET_LEN(space->chain) == 0|| 1 and
introducint two new functions that access filespace list
and before returning space check that node is also created.
Make sure that when we publish the crypt_data we access the
memory cache of the tablespace crypt_data. Make sure that
crypt_data is stored whenever it is really needed.
All this is not yet enough in my opinion because:
sql/encryption.cc has DBUG_ASSERT(scheme->type == 1) i.e.
crypt_data->type == CRYPT_SCHEME_1
However, for InnoDB point of view we have global crypt_data
for every tablespace. When we change variables on crypt_data
we take mutex. However, when we use crypt_data for
encryption/decryption we use pointer to this global
structure and no mutex to protect against changes on
crypt_data.
Tablespace encryption starts in fil_crypt_start_encrypting_space
from crypt_data that has crypt_data->type = CRYPT_SCHEME_UNENCRYPTED
and later we write page 0 CRYPT_SCHEME_1 and finally whe publish
that to memory cache.
Analysis: Problem was that tablespaces not encrypted might not have
crypt_data stored on disk.
Fixed by always creating crypt_data to memory cache of the tablespace.
MDEV-8138: strange results from encrypt-and-grep test
Analysis: crypt_data->type is not updated correctly on memory
cache. This caused problem with state tranfer on
encrypted => unencrypted => encrypted.
Fixed by updating memory cache of crypt_data->type correctly based on
current srv_encrypt_tables value to either CRYPT_SCHEME_1 or
CRYPT_SCHEME_UNENCRYPTED.
* Extract it into the "encryption_scheme" service.
* Make these engines to use the service, remove duplicate code.
* Change MY_AES_xxx error codes, to return them safely
from encryption_scheme_encrypt/decrypt without conflicting
with ENCRYPTION_SCHEME_KEY_INVALID error
Analysis: Problem was that we did create crypt data for encrypted table but
this new crypt data was not written to page 0. Instead a default crypt data
was written to page 0 at table creation.
Fixed by explicitly writing new crypt data to page 0 after successfull
table creation.
With changes:
* update tests to pass (new encryption/encryption_key_id syntax).
* not merged the code that makes engine aware of the encryption mode
(CRYPT_SCHEME_1_CBC, CRYPT_SCHEME_1_CTR, storing it on disk, etc),
because now the encryption plugin is handling it.
* compression+encryption did not work in either branch before the
merge - and it does not work after the merge. it might be more
broken after the merge though - some of that code was not merged.
* page checksumming code was not moved (moving of page checksumming
from fil_space_encrypt() to fil_space_decrypt was not merged).
* restored deleted lines in buf_page_get_frame(), otherwise
innodb_scrub test failed.
* no --encryption-algorithm option anymore
* encrypt/decrypt methods in the encryption plugin
* ecnrypt/decrypt methods in the encryption_km service
* file_km plugin has --file-key-management-encryption-algorithm
* debug_km always uses aes_cbc
* example_km changes between aes_cbc and aes_ecb for different key versions
Step 3:
-- Make encrytion_algorithm changeable by SUPER
-- Remove AES_ECB method from encryption_algorithms
-- Support AES method change by storing used method on InnoDB/XtraDB objects
-- Store used AES method to crypt_data as different crypt types
-- Store used AES method to redo/undo logs and checkpoint
-- Store used AES method on every encrypted page after key_version
-- Add test
Step 2:
-- Introduce temporal memory array to buffer pool where to allocate
temporary memory for encryption/compression
-- Rename PAGE_ENCRYPTION -> ENCRYPTION
-- Rename PAGE_ENCRYPTION_KEY -> ENCRYPTION_KEY
-- Rename innodb_default_page_encryption_key -> innodb_default_encryption_key
-- Allow enable/disable encryption for tables by changing
ENCRYPTION to enum having values DEFAULT, ON, OFF
-- In create table store crypt_data if ENCRYPTION is ON or OFF
-- Do not crypt tablespaces having ENCRYPTION=OFF
-- Store encryption mode to crypt_data and redo-log
Step 1:
-- Remove page encryption from dictionary (per table
encryption will be handled by storing crypt_data to page 0)
-- Remove encryption/compression from os0file and all functions
before that (compression will be added to buf0buf.cc)
-- Use same CRYPT_SCHEME_1 for all encryption methods
-- Do some code cleanups to confort InnoDB coding style
