The socket creation code in mysql_backend.c wasn't MySQL specific and it
could be used for all non-blocking network connections. Thus, it makes
sense to move it to a common file where other protocol modules can use
it.
The address resolution code now uses `getaddrinfo` to resolve all
addresses instead of manually handling wildcard hosts. This allows the
same code to be used for all addresses.
Both the listeners and servers now support IPv6 addresses.
The namedserverfilter does not yet use the new structures and needs to be
fixed in a following commit.
Thread-safe version of strerror; thread local buffer used for storing
the message. The performance penalty of a thread local buffer is not
likely to be significant, since this is only called in an error
situation that anyway is likely to interrupt the normal processing.
The SQLite database is now always created on disk. This will remove the
need to dump the database users from the in-memory database to the
persisted on-disk database.
This change will also make the authentication compatible with older SQLite
implementations which lack the URI-based database strings found in newer
versions.
The authenticators should have a similar way to print diagnostic
information as filter and routers do. This allows the authenticators to
print the users in their own format.
In the future, all the diagnostic entry points should be changed so that
they return a structure that contains the information in a standard
form. This information can then be formatted in different ways by other
modules.
MariaDB and others match grants first by exact hostname/IP and then by
wildcard. If there are no exact matches, the wildcard grant should be
picked. This can be tested by having different passwords for localhost and
remote address.
The SQLite based authentication should first check for an exact match and
then only after that should it try to match the hostname to a wildcard
grant.
The get_users function now combines the functionality of the old get_users
and get_all_users. This removes large parts of similar code.
Removed the listener resources as MySQLAuth was the only one that used it.
The user data is now stored inside a SQLite3 database. By storing the data
inside a database, we remove the restriction that the previous hashtable
based implementation had.
Currently the only situation where a user needs to be authenticated after
the initial authentication is when a COM_CHANGE_USER is being
executed. This was previously handled by directly calling a function in
the MySQLAuth authenticator.
The new entry in the API of the authenticators is very specific to MySQL
and should be reviewed once other protocols are added.
When the real root master server went down, it still received the master
status bit due to how the replication tree was built. The bit should only
be set for servers that are running.
Also fixed a false state change event when the master status bit was
manually cleared from the downed root master server.
The order of the servers in the service definition could break the
master_accept_reads functionality.
When the first server defined in the service is a slave, it will always be
picked as the first candidate for reads. The master would only be
considered as a candidate for reads if no previous candidate was
available. For this reason, the master_accept_reads only worked when the
first server in the list was the master.
GCC on CentOS6 thinks there is an array-bounds error in the sqlite
code. As that code is outside our hands, it is easiest to instruct
GCC not to treat it as an error.
Change to modutil_extract_SQL(), add pcre2_data to filter session.
The pattern is now jit-compiled for maximum speed. Move general
pcre2 error printing to a function and macro. Add instance-level
statistics so the filter always prints diagnostic info. Add a mention
of PCRE2 to release notes.
The routers no longer need to track the number of errors each DCB
receives. This is now done by the protocol modules.
The type of the DCB no longer needs to be checked in the handleError
implementation as the function is only called when a backend DCB fails.
Refactored common code into a reusable function. Now all of the backend
error handling uses the same function.
Moved responsibility of the DCB error handling tracking to the backend
protocol. The routers no longer need to manage the
`dcb->dcb_errhandle_called` variable of the failed DCB.
Removed calls to handleError with client DCBs as parameters. All of the
routers close the DCB given to handleError if it is a client DCB. The only
time the error handler would be called is when the routeQuery function
fails. The handleError call is redundant as the router already knows that
the session should be closed when it returns from routeQuery.
If one queried in MySQL MaxInfo 'show sessions' or 'show clients',
MaxScale would go in an endless loop and finally crash when memory
ran out. The reason is the rather confusing callback-based dcb-
iterating code. Adding one line fixes the issue, although the iteration
is still rather awkward with calling dcb_foreach for every session/
client.
