Xtrabackup doesn't accept sha256 passwords

[Jaime Sicam]

my.cnf:
[mysqld]
default-authentication-plugin=sha256_password

Create a user with SHA 256 password:
mysql> set old_passwords=2;
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> set password for user@'%' = password('secret');
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

Run xtrabackup 2.4.4:
[root@localhost ~]# innobackupex --host=127.0.0.1 --user=shaman --password=secret /backups/
161006 02:52:26 innobackupex: Starting the backup operation

IMPORTANT: Please check that the backup run completes successfully.
           At the end of a successful backup run innobackupex
           prints "completed OK!".

perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
 LANGUAGE = (unset),
 LC_ALL = (unset),
 LC_CTYPE = "UTF-8",
 LANG = "en_US.UTF-8"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
161006 02:52:26 version_check Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup;host=127.0.0.1;mysql_socket=/var/lib/mysql/mysql.sock' as 'shaman' (using password: YES).
Failed to connect to MySQL server: DBI connect(';mysql_read_default_group=xtrabackup;host=127.0.0.1;mysql_socket=/var/lib/mysql/mysql.sock','shaman',...) failed: Client does not support authentication protocol requested by server; consider upgrading MySQL client at - line 1314
161006 02:52:26 Connecting to MySQL server host: 127.0.0.1, user: shaman, password: set, port: 0, socket: /var/lib/mysql/mysql.sock
Failed to connect to MySQL server: Authentication plugin 'sha256_password' cannot be loaded: /usr/lib/plugin/sha256_password.so: cannot open shared object file: No such file or directory.

Do note that sha256_password is a built-in plugin

[Sergei Glushchenko (sergei.glushchenko)]

This bug report related to bug 1546872 and patch will fix both of them.

There are two cases when sha256 passwords are allowed:

1. Connection is encrypted with SSL (works both with client built with YaSSL and OpenSSL)
2. Client is built with OpenSSL and server is started with private-key-path/public-key-path specified

Both don't work currently.

The fix will:

1. Allow to build xtrabackup with SSL support (with choice of YaSSL or OpenSSL)
2. Link sha256 plugin

Changes need to be done in packaging:

1. Make sure RPM and DEB versions build xtrabackup with system OpenSSL
2. Build binary tarball with YaSSL (or provide several versions for different distros) -- to be decided

[Sergei Glushchenko (sergei.glushchenko)]

  - https://github.com/percona/percona-xtrabackup/pull/256
  - https://github.com/percona/percona-xtrabackup/pull/257

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PXB-766