Category Archives: Security

LDAP with auth_pam and Python to authenticate against MySQL

If that title looks familiar, it is because a few months ago I posted about LDAP with auth_pam and PHP to authenticate against MySQL.

The good news is that recompiling the connector for Python is a lot easier than for PHP. With PHP, the complexity was due to there being one monolithic package to recompile. The bad news is that there is a slight hitch with Python.

Skip down to the hitch and how to compile MySQLdb for use with auth_pam plugin.

As a quick reminder, here is a repeat of the background:

Background


There are two plugins that can be used. From the documentation, the two plugins are:

  • Full PAM plugin called auth_pam. This plugin uses dialog.so. It fully supports the PAM protocol with arbitrary communication between client and server.
  • Oracle-compatible PAM called auth_pam_compat. This plugin uses mysql_clear_password which is a part of Oracle MySQL client. It also has some limitations, such as, it supports only one password input. You must use -p option in order to pass the password to auth_pam_compat.

Percona’s MySQL client supports both plugins natively. That is, you can use auth_pam or auth_pam_compat and use the “mysql” tool (or “mysqldump”, or mysql_upgrade, etc.) and you are good to go. Given the choice, we would all use auth_pam, under which clients DO NOT use mysql_clear_password.

Not all clients support auth_pam, which is the main problem. Workarounds have called for using auth_pam_compat over SSL, which is a perfectly reasonable way to handle the risk of cleartext passwords – encrypt the connection.

However, what if you want to use auth_pam, and avoid cleartext passwords all together?

If you try to connect to MySQL using Python, you will receive this error: “Client does not support authentication protocol requested by server; consider upgrading MySQL client.”

Back in 2013, Percona posted about how to install and configure auth_pam and auth_pam_compat. The article explains how to recompile clients to get them to work:

The good news is that if the client uses libmysqlclient library to connect via MySQL, you can recompile the client’s source code to use the libmysqlclient library of Percona Server to make it compatible. This involves installing Percona Server development library, compiler tools, and development libraries followed by compiling and installing the client’s source code.

The Hitch


The hitch with Python is that there are a few different ways to connect to MySQL with Python. In fact, MySQL has written a Python connector, called mysql-connector-python. According to the documentation for mysql-connector-python:

It is written in pure Python and does not have any dependencies except for the Python Standard Library.

This means we cannot recompile mysql-connector-python to use the libmysqlclient library from Percona that supports auth_pam – because it does not use the libmysqlclient library.

However, mysql-connector-python is not the only way to connect MySQL to python. There is a mysqlclient-python package, which provides the MySQLdb module for connecting to MySQL. According to the documentation:

MySQLdb is a thin Python wrapper around _mysql

And the docs for the _mysql module say:

_mysql provides an interface which mostly implements the MySQL C API.

It is using the standard library, and we can recompile it. Here is a mirror of the Perl recompilation process for MySQL.

Recompiling MySQLdb to support auth_pam

Step 1

“Install Percona yum repository and Percona Server development library.” This is not a problem, do what you need to do to install Percona-Server-devel for your version.

Step 2

Install a package manager so you can build a package – optional, but useful, if you ever want to have this new client without having to recompile. As in the example, I chose the RPM package manager, so I installed rpm-build.

Step 3

“Download and install the source RPM for the client package.”

I did a web search for “mysqlclient-python source rpm” and found the rpmfind page containing many versions. If you click on the link in the “Package” column you will get to a page that has a link for the Source RPM. I chose the most recent (as of this writing) CentOS package.

So I downloaded the source RPM and installed it into the sources directory:

cd SRPMS
wget http://vault.centos.org/7.4.1708/os/Source/SPackages/MySQL-python-1.2.5-1.el7.src.rpm
cd ../SOURCES
rpm -Uvh MySQL-python-1.2.5-1.el7.src.rpm

This unpacks MySQL-python-1.2.5.zip and a patch file in the SOURCES directory and puts a spec file in the SPECS directory, so this is not as complicated as the PHP version.

Step 4

“Install compilers and dependencies”.
On my host I had no work to get any requirements installed (your mileage may vary – I had installed a lot of dependencies previously in my PHP test, and used the same machine). Make sure to include the Percona Server package for the /usr/lib64/mysql/plugin/dialog.so file:
yum install Percona-Server-server-55-5.5.55-rel38.8.el6.x86_64

Step 5

“Build the RPM file”.


rpmbuild -bb rpmbuild/SPECS/MySQL-python.spec

Then I installed my new package and tested it, and it worked!
# rpm -e MySQL-python
# rpm -Uvh /root/rpmbuild/RPMS/x86_64/MySQL-python-1.2.5-1.el6.x86_64.rpm
Preparing… ########################################### [100%]
1:MySQL-python ########################################### [100%]

I will not be continuing this experiment with any other clients (e.g. not going to try for Ruby) but I welcome others to do the same!

Lesson 09: Managing Users and Privileges in MySQL

Notes/errata/updates for Chapter 9:
See the official book errata at http://tahaghoghi.com/LearningMySQL/errata.php – Chapter 9 includes pages 297 – 350.

In the fourth paragraph of this chapter, starting with “Most applications don’t need superuser privileges for day-to-day activities” they give you some reasons why you want to create users without the SUPER privilege. There are better reasons than the book gives, which are at the MySQL Manual page for the SUPER privilege.

In the section “Creating and Using New Users” (p. 300) they say “There’s no limit on password length, but we recommend using eight or fewer characters because this avoids problems with system libraries on some platforms.” You should ignore this, this book was written in 2006 and modern system libraries can handle more than 8 characters in a password. Also ignore it when they say the same thing in the section “Understanding and Changing Passwords” (p. 324).

In the section “Creating a New Remote User” at the very end (p. 214), it talks about using % as a host wildcard character. I want to point out that if there are no ACL’s set for a given host, MySQL will reject ALL connections from that host – even “telnet host 3306” will fail. So if you avoid using %, you are slightly more secure.

In the “Anonymous Users” section (p. 315), one fact that is not mentioned is that for all users, including the anonymous user, any database named “test” or that starts with “test_” can be accessed and manipulated. So an anonymous user can create tables in the “test” database (or even “test_application”) and fill it full of data, causing a denial of service when the disk eventually fills up. This fact is mentioned later in the chapter in the “Default User Configuration” section under “Linux and Mac OS X”, but it should be known earlier.

The “mysqlaccess” utility described in the section of that name (p. 320) is usually not used. These days, folks prefer the pt-show-grants tool. Here is a blog post with some examples of pt-show-grants.

In the section on “Removing Users” (p. 324), it says that if all the privileges are revoked, and a user only has GRANT USAGE, “This means the user can still connect, but has no privileges when she does.” This is untrue, as mentioned before, everyone can access and manipulate databases starting with “test”.

The section “Managing Privileges with SQL” is deprecated (p. 339-346, up to and including “Activating Privileges”). It used to be, back when this was written, that few people used the GRANT statements and more people directly manipulated the tables. These days, it’s the other way around, and due to problems like SQL injection, there are safeguards in place – for example, if you change the host of a user with an ALTER TABLE on the mysql.user table, the user will have all privileges dropped. Just about the only thing direct querying is used for, is to find who has the Super_priv variable set to ‘Y’ in the user table.

Supplemental material: I have a video presentation on security which includes ACLs and there are accompanying PDF slides.

Topics covered:
Creating and dropping local and remote users
Different MySQL privileges
SUPER privilege
GRANT and REVOKE syntax
Hosts and wildcards
Anonymous and default users
Checking privileges
Password management
Basic user security
Resource limit controls

Reference/Quick Links for MySQL Marinate

MySQL Marinate – So you want to learn MySQL! – START HERE

Want to learn or refresh yourself on MySQL? MySQL Marinate is the FREE virtual self-study group is for you!

MySQL Marinate quick links if you know what it is all about.

This is for beginners – If you have no experience with MySQL, or if you are a developer that wants to learn how to administer MySQL, or an administrator that wants to learn how to query MySQL, this course is what you want. If you are not a beginner, you will likely still learn some nuances, and it will be easy and fast to do. If you have absolutely zero experience with MySQL, this is perfect for you. The first few chapters walk you through getting and installing MySQL, so all you need is a computer and the book.

The format of a virtual self-study group is as follows:
Each participant acquires the same textbook (Learning MySQL, the “butterfly O’Reilly book”, published 2007). You can acquire the textbook however you want (e.g. from the libary or from a friend, hard copy or online). Yes, the book is old, but SQL dates back to at least the 1970’s and the basics haven’t changed! There are notes and errata for each chapter so you will have updated information. The book looks like this:

O'Reilly Butterfly book picture

O’Reilly Butterfly book picture

Each participant commits to reading each chapter (we suggest one chapter per week as a good deadline), complete the exercises and post a link to the completed work.

Each participant obtains assistance by posting questions to the comments on a particular chapter.

Note: There is no classroom instruction.

How do I get started?

– Watch sheeri.com each week for the chapters to be posted.

– Get Learning MySQL
Acquire a book (the only item that may cost money). Simply acquire Learning MySQL – see if your local library has it, if someone is selling their copy, or buy it new.

– Start!
When your book arrives, start your virtual learning by reading one chapter per week. Complete the exercises; if you have any questions, comments or want to learn more in-depth, that’s what the comments for!

FAQs:
Q: Does this cover the Percona patch set or MariaDB forks?

A: This covers the basics of MySQL, which are applicable to Percona’s patched MySQL or MariaDB builds, as well as newer versions of MySQL.

Q: What do I need in order to complete the course?

A: All you need is the book and access to a computer, preferably one that you have control over. Windows, Mac OS X or Unix/Linux will work. A Chromebook or tablet is not recommended for this course.

Q: Where can I put completed assignments?

A: Completed assignments get uploaded to github. See How to Submit Homework

Q: The book was published in 2007. Isn’t that a bit old?

A: Yes! The basics are still accurate, and we will let you know what in the book is outdated. I have contacted O’Reilly, offering to produce a new edition, and they are not interested in updating the book. We will also have optional supplemental material (blog posts, videos, slides) for those who want to learn more right away. We are confident that this self-study course will make you ready to dive into other, more advanced material.

Soak it in!

Reference/Quick Links for MySQL Marinate

LDAP with auth_pam and PHP to authenticate against MySQL

Edited to add a link to the Python version.

In the quest to secure MySQL as well as ease the number of complicated passwords to remember, many organizations are looking into external authentication, especially using LDAP. For free and open source, Percona’s PAM authentication plugin is the standard option.

tl;dr is I go through how to compile php-cli for use with auth_pam plugin.

Background


There are two plugins that can be used. From the documentation, the two plugins are:

  • Full PAM plugin called auth_pam. This plugin uses dialog.so. It fully supports the PAM protocol with arbitrary communication between client and server.
  • Oracle-compatible PAM called auth_pam_compat. This plugin uses mysql_clear_password which is a part of Oracle MySQL client. It also has some limitations, such as, it supports only one password input. You must use -p option in order to pass the password to auth_pam_compat.

Percona’s MySQL client supports both plugins natively. That is, you can use auth_pam or auth_pam_compat and use the “mysql” tool (or “mysqldump”, or mysql_upgrade, etc.) and you are good to go. Given the choice, we would all use auth_pam, under which clients DO NOT use mysql_clear_password.

Not all clients support auth_pam, which is the main problem. Workarounds have called for using auth_pam_compat over SSL, which is a perfectly reasonable way to handle the risk of cleartext passwords – encrypt the connection.

However, what if you want to use auth_pam?

The problem with auth_pam

Back in 2013, Percona posted about how to install and configure auth_pam and auth_pam_compat. I will not rehash that setup, except to say that most organizations no longer use /etc/shadow, so the setup involves getting the correct /etc/pam.d/mysqld in place on the server.

That article has this gem:

As of now, only Percona Server’s mysql client and an older version of HeidiSQL(version 7), a GUI MySQL client for Windows, are able to authenticate over PAM via the auth_pam plugin by default.

So, if you try to connect to MySQL using Perl, PHP, Ruby, Python and the like, you will receive this error: “Client does not support authentication protocol requested by server; consider upgrading MySQL client.”

Fast forward 4 years, to now, and this is still an issue. Happily, the article goes on to explain how to recompile clients to get them to work:

The good news is that if the client uses libmysqlclient library to connect via MySQL, you can recompile the client’s source code to use the libmysqlclient library of Percona Server to make it compatible. This involves installing Percona Server development library, compiler tools, and development libraries followed by compiling and installing the client’s source code.

And, it helpfully goes step by step on how to recompile perl-DBD-mysql to get it working with LDAP authentication (as well as without – it still works for users who do not use LDAP).

But what if you are using PHP to connect to MySQL?

PHP and auth_pam


If you try to connect, you get this error:
SQLSTATE[HY000] [2054] The server requested authentication method unknown to the client

So let us try to mirror the perl recompilation process in PHP.

Step 1

“Install Percona yum repository and Percona Server development library.” This is not a problem, do what you need to do to install Percona-Server-devel for your version.

Step 2

Install a package manager so you can build a package – optional, but useful, if you ever want to have this new client without having to recompile. As in the example, I chose the RPM package manager, so I installed rpm-build.

Step 3

Download and install the source RPM for the client package. This is where I started running into trouble. What I did not realize was that PHP does not divide out its packages like Perl does. Well, it does, but php-mysqlnd is compiled as part of the core, even though it is a separate package.

Downloading the main PHP package


So I downloaded the source RPM for PHP at https://rpms.remirepo.net/SRPMS/, and installed it into the sources directory:
cd SRPMS
wget https://rpms.remirepo.net/SRPMS/php-7.0.22-2.remi.src.rpm
cd ../SOURCES
rpm -Uvh ../SRPMS/php-7.0.22-2.remi.src.rpm

This unpacks a main file, php-7.0.22.tar.xz, plus a bunch of supplemental files (like patches, etc).

What it does NOT contain is a spec file, which is critical for building the packages.

Getting a spec file


I searched around and found one at https://github.com/iuscommunity-pkg/php70u/blob/master/SPECS/php70u.spec – this is for 7.0.21, so beware of using different versions of spec files and source code. Once that was done, I changed the mysql lines to /usr/bin/mysql_config as per Choosing a MySQL library. Note that I went with the “not recommended” library, but in this case, we WANT to compile with libmysqlclient.

Compiling php-cli, not php-mysqlnd


In addition, I discovered that compiling php-mysqlnd with the new libraries did not work. Perhaps it was something I did wrong, as at that point I was still compiling the whole PHP package and every module in it.

However, what I *did* discover is that if I recompiled the php-cli package with libmysqlclient, I was able to get a connection via PHP using LDAP authentication, via a tool written by someone else – with no changes to the tool.

Final spec file


So here is the spec file I eventually came up with. I welcome any optimizations to be made!

Step 4

“Install compilers and dependencies”.
On my host I had to do a bunch of installations to get the requirements installed (your mileage may vary), including the Percona Server package for the /usr/lib64/mysql/plugin/dialog.so file:
yum install Percona-Server-server-55-5.5.55-rel38.8.el6.x86_64 libtool systemtap-sdt-devel unixODBC-devel

Step 5

“Build the RPM file”. Such an easy step, but it took about a week of back and forth with building the RPM file (which configures, tests and packages up everything), so I went between this step and updating the spec file a lot.


rpmbuild -bb /root/rpmbuild/SPECS/php-cli.spec

Then I installed my PHP file and tested it, and it worked!
# rpm -e php-cli –nodeps
# rpm -Uvh /root/rpmbuild/RPMS/x86_64/php70u-cli-7.0.22-2.ius.el6.x86_64.rpm –nodeps
Preparing… ########################################### [100%]
1:php70u-cli ########################################### [100%]

I hope you have similar success, and if you have updates to the spec files and lists of packages to install, please let me know!

Testing Advanced Log Flushing for Percona Audit

We use Percona’s <A HREF=”https://www.percona.com/doc/percona-server/5.5/management/audit_log_plugin.html”>audit log plugin</A> to keep a record of all our logins. Recently we did one of those tasks that everyone knows they should do, but few ever do: change the application user’s password.

When we change the application password, we add a new application user with the proper permissions and a new password, update the information in our repository and wait a while. Using this procedure, any failures mean the old user is used, and more importantly – failure does not impact the end user.

We check the audit logs to see if there were failures – if the user is still being used – when it is no longer in use, we can drop the user.

For reference, here are our settings:

[mysqlaudit]# grep audit /etc/my.cnf
# Percona audit plugin options
audit_log_format = JSON
audit_log_rotate_on_size = 1073741824 . #1G
audit_log_rotations = 10
audit_log_file = /var/log/mysqlaudit/audit.log
audit_log_buffer_size = 4194304
audit_log_strategy = ASYNCHRONOUS
audit_log_policy = LOGINS

This means that we automatically flush logs >1G, keeping 10 audit logs. The other option is to do manual flushing, but we do not want our log files to get very large, and we don’t need to keep audit logs for a very long time.

The ideal behavio – we update our app to the new user, and then flush the logs. That way we could start a new audit log and only have to search the current audit log for the old user. I’m sure people are thinking, “well, it’s set to rotate by size, not manually, so you just cannot do it.” However, binary logs are set the same way and FLUSH LOGS do indeed rotate logs manually, even when auto rotate by size is set.

The tl;dr is that there is currently no way to do this without restarting MySQL. The audit_log_rotate_on_size variable is not dynamic, so we could not set it to manual without restarting MySQL. Here are some other tests we did to see if we could force an audit log flush while using the auto rotate:

We tried moving the audit logs and flushing:

[ ~]# cd /var/log/mysqlaudit/
[mysqlaudit]# ls -l
total 1459572
-rw-rw—- 1 mysql mysql 420839439 Mar 31 11:04 audit.log
-rw-rw—- 1 mysql mysql 1073749720 Mar 25 08:50 audit.log.01
[mysqlaudit]# mv audit.log.01 audit.log.02
[mysqlaudit]# mv audit.log audit.log.01
[mysqlaudit]# ls
audit.log.01 audit.log.02

Don’t worry, this doesn’t affect writing the file – the inode is still in MySQL and it still writes to the file, now called audit.log.01:
[mysqlaudit]# ls -l
total 1459652
-rw-rw—- 1 mysql mysql 420925253 Mar 31 11:07 audit.log.01
-rw-rw—- 1 mysql mysql 1073749720 Mar 25 08:50 audit.log.02
[mysqlaudit]# ls -l
total 1459652
-rw-rw—- 1 mysql mysql 420925253 Mar 31 11:07 audit.log.01
-rw-rw—- 1 mysql mysql 1073749720 Mar 25 08:50 audit.log.02
[mysqlaudit]# mysql -u sheeri.cabral -p -e “FLUSH LOGS;”
Enter password:
[mysqlaudit]# ls -l
total 1459688
-rw-rw—- 1 mysql mysql 420958983 Mar 31 11:07 audit.log.01
-rw-rw—- 1 mysql mysql 1073749720 Mar 25 08:50 audit.log.02

Note that this also proves that “FLUSH LOGS” does not close and open the audit log.

Can we force it? Let’s try by setting the audit_log_policy to NONE and then to LOGINS (what we have it as by default):

[mysqlaudit]# mysql -u sheeri.cabral -p -e “set global audit_log_policy=NONE; set global audit_log_policy=LOGINS”
Enter password:
[mysqlaudit]# ls -l
total 1459768
-rw-rw—- 1 mysql mysql 421043317 Mar 31 11:10 audit.log.01
-rw-rw—- 1 mysql mysql 1073749720 Mar 25 08:50 audit.log.02

Here’s another failed test – let’s see if we can disable then enable the plugin:
[mysqlaudit]# mysql -u sheeri.cabral -p -e “UNINSTALL PLUGIN audit_log”
Enter password:
[mysqlaudit]# ls -rlth
total 1.4G
-rw-rw—- 1 mysql mysql 1.1G Mar 25 08:50 audit.log.01
-rw-rw—- 1 mysql mysql 403M Mar 31 11:44 audit.log
[mysqlaudit]# mysql -u sheeri.cabral -p -e “INSTALL PLUGIN audit_log SONAME ‘audit_log.so’; ”
Enter password:
ERROR 1125 (HY000) at line 1: Function ‘audit_log’ already exists
[mysqlaudit]# mysql -u sheeri.cabral -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1375345
Server version: 5.5.51-38.1-log Percona Server (GPL), Release 38.1, Revision b4a63b4

Copyright (c) 2009-2016 Percona LLC and/or its affiliates
Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type ‘help;’ or ‘\h’ for help. Type ‘\c’ to clear the current input statement.

[(none)]> \P grep -i audit
PAGER set to ‘grep -i audit’
[(none)]> SHOW PLUGINS;
| audit_log | DELETED | AUDIT | audit_log.so | GPL |
41 rows in set (0.00 sec)

[(none)]> INSTALL PLUGIN audit_log SONAME ‘audit_log.so’;
ERROR 1125 (HY000): Function ‘audit_log’ already exists

So, I ended up needing to restart MySQL if I wanted to re-enable the plugin.

Sometimes the failures are the most illuminating!

[I realize that the plugin probably could not hack FLUSH LOGS but it would be great to get FLUSH AUDIT or something similar…]

Generating a MySQL Password

One of the services our database engineers provide is adding users to MySQL. We have some nice Chef recipes, so all I have to do is update a few files, including adding in the MySQL password hash.

Now, when I added myself, I just logged into MySQL and generated a password hash. But when my SRE (systems reliability engineer) colleague needed to generate a password, he did not have a MySQL system he could login to.

The good news is it’s easy to generate a MySQL password hash. The MySQL password hash is simply a SHA1 hash of a SHA1 hash, with * at the beginning. Which means you do not need a MySQL database to create a MySQL password hash – all you need is a programming language that has a SHA1 function (well, and a concatenate function).

And I found it, of course, on this post at StackExchange (http://unix.stackexchange.com/a/234592/217471). So you don’t have to click through, here is what it says – and I have tested all these methods and I get the same password hash. I have changed their example of “right” to “PASSWORD HERE” so it’s more readable and obvious where the password goes, in case you copy and paste from here.

Some one-liners:

**MySQL** (may require you add -u(user) -p):

mysql -NBe "select password('PASSWORD HERE')"

**Python**:

python -c 'from hashlib import sha1; print "*" + sha1(sha1("PASSWORD HERE").digest()).hexdigest().upper()'

**Perl**:

perl -MDigest::SHA1=sha1_hex -MDigest::SHA1=sha1 -le ‘print “*”. uc sha1_hex(sha1(“PASSWORD HERE”))’

**PHP**:

php -r 'echo "*" . strtoupper(sha1(sha1("PASSWORD HERE", TRUE))). "\n";'

Hopefully these help you – they enabled my colleagues to easily generate what’s needed without having to find (or create) a MySQL instance that they can already login to.

What is an “unauthenticated user”?

Every so often we have a client worrying about unauthenticated users. For example, as part of the output of SHOW PROCESSLIST they will see:

+-----+----------------------+--------------------+------+---------+------+-------+------------------+
| Id  | User                 | Host               | db   | Command | Time | State | Info             |
+-----+----------------------+--------------------+------+---------+------+-------+------------------+
| 235 | unauthenticated user | 10.10.2.74:53216   | NULL | Connect | NULL | login | NULL             |
| 236 | unauthenticated user | 10.120.61.10:51721 | NULL | Connect | NULL | login | NULL             |
| 237 | user                 | localhost          | NULL | Query   | 0    | NULL  | show processlist |
+-----+----------------------+--------------------+------+---------+------+-------+------------------+

Who are these unauthenticated users, how do they get there, and why aren’t they authenticated?

The client-server handshake in MySQL is a 4-step process. Those familiar with mysql-proxy already know these steps, as there are four functions that a Lua script in mysql-proxy can override. The process is useful to know for figuring out exactly where a problem is when something breaks.

Step 1: Client sends connect request to server. There is no information here (as far as I can tell). However, it does mean that if you try to connect to a host and port of a mysqld server that is not available, you will get

ERROR 2003 (HY000): Can't connect to MySQL server on '[host]' (111)

Step 2: The server assigns a connection and sends back a handshake, which includes the server’s mysqld version, the thread id, the server host and port, the client host and port, and a “scramble buffer” (for salting authentication, I believe).

It is during Step 2 where the connections show up in SHOW PROCESSLIST. They have not been authenticated yet, but they are connected. If there are issues with authentication, connections will be stuck at this stage. Most often stuck connections are due to DNS not resolving properly, which the skip-name-resolve option will help with.

Step 3: Client sends authentication information, including the username, the password (salted and hashed) and default database to use. If the client sends an incorrect packet, or does not send authentication information within connect_timeout seconds, the server considers the connection aborted and increments its Aborted_connects status variable.

Step 4: Server sends back whether the authentication was successful or not. If the authentication was not successful, mysqld increments its Aborted_connects status variable and sends back an error message:

ERROR 1045 (28000): Access denied for user 'user'@'host' (using password: [YES/NO])

Hope this helps!

April 2007 Boston MySQL User Group Video

Using MySQL As Active DBMS for Monitoring Applications — Jacob Nikom.

Jacob presented this as a special preview at the April 2007 Boston MySQL User Group, and then presented it at the 2007 MySQL Users Conference and Expo.

The last in the “better late than never” series….

Download from http://www.technocation.org/videos/2007_04BostonUserGroup.wmv
or view right here:

MySQL Security Presentation at Boston MySQL User Group Meeting

The February Boston MySQL User Group meeting was great! I spoke about MySQL security; you can now download the slides and the video. I continue to be impressed with the sound quality of the video camera I have, I was pretty good about repeating the question folks asked, but you can clearly hear it in the audio (well, I could when I was wearing headphones, but I also have pretty bad hearing).

Special thanks to http://technocation.org for hosting the bandwidth for the videos.

Topics covered in the talk:
ACLs
Test dbs & anonymous accounts
OS files and permissions
Application data flow
SQL Injection
XSS (Cross-site scripting)

PDF of slides (1.4M):
http://www.sheeri.com/presentations/MySQLSecurity2007_02_08.pdf

Slides in Flash (107K):
http://www.sheeri.com/presentations/MySQLSecurity2007_02_08.swf

Video of presentation (large, 289M)
http://technocation.org/videos/original/mysqlsecurity2007_02_08large.wmv

Video of presentation (small, 27M)
http://technocation.org/videos/original/mysqlsecurity2007_02_08small.wmv

User Group Video Up, and Video Camera Review

Download the video at:

http://technocation.org/videos/original/BostonMySQLJanUserGroupBrianAkerLg.wmv
– 520 kbps, 320 x 240, 354M. Small size, low quality, but you can still see the slides and hear everything.

http://technocation.org/videos/original/BostonMySQLJanUserGroupBrianAkerSm.wmv – 45 kbps, 320 x 120, 29M. Small size, low quality, but you can still see the slides and hear everything.

Technocation, Inc. received a donation of a Sony Handycam DCR SR80 (http://tinyurl.com/yvyfam ), extra-long battery, microphone (proprietary Sony that goes with the camera).

In a short sentence: I am impressed. The sound quality (on the large version) is almost exactly what I heard. Granted, I have some hearing loss, but I forgot to bring the microphone, and you can still hear audience questions very well. The video quality is great, too. The hard disk is perfect, because files can be copied over or burned directly to DVD. It records in MPEG-4 format.

The 1 hour 38 minute talk took up less than 6 gigs of space raw (I forget how much exactly, but it cuts the files into 2G chunks, and there were 3). This gives at least 10 hours of recording time before needing to dump to disk. This is a very exciting prospect for the MySQL Conference and Expo at the end of April, I’ll be able to video a LOT.

Special thanks go to the User Group member (who may wish to remain anonymous, but I forgot his name anyway, so if he wishes to comment he can, or just e-mail me so I remember your name!) who talked to me about codecs and which programs to use, because they worked!

I was not quite ready for the start of the User Group, and had to run out to my car to get the tripod, so the first minute or so (until 1:25) is me setting up the tripod — I apologize for the movement.

You can see the “Night Shot” functionality early on, when I focus on Brian and turn it on. It does a great job, but loses a lot of color (1:53 until 1:59).

I was disappointed that when you connect the DC power supply, the video stops (so there’s a few hops int here).

Brian takes some slides, starts talking, and questions ensue. The basic slides were about MySQL’s internal architecture.

Some links:
MySQL and dual-master/circular replication
There’s a great article by Guiseppe Maxia at: http://www.onlamp.com/pub/a/onlamp/2006/04/20/advanced-mysql-replication.html

And a free chapter on Replication from Jeremy Zawodny’s
http://www.oreilly.com/catalog/hpmysql/chapter/ch07.pdf

Around 27:00 there is a reference to Jim Gray’s “Black Book”, which is entitled “Transaction Processing: Concepts and Techniques” and can be found here: http://tinyurl.com/2md3tb

http://forge.mysql.com/wiki/Top10SQLPerformanceTips