Why you should use salted user password hashes¶
By using this extension, you get rid of plain-text passwords or MD5 password hashes for user records in TYPO3. MD5 hashes are no longer safe to use for passwords. Using rainbow tables is widely spread these days and retrieving an according valid plain-text password is just a matter of time. With salted hashes, an attacker needs to create separate rainbow tables for each salt. The salt itself is different for each stored password hash. So retrieving plain-text passwords for all user records in a TYPO3 installation is quite expensive in terms of complexity.
You still are advised to use well-chosen passwords. Avoid wordlist entries; use arbitrary complex non-wordlist passwords/passphrases.
Supported hashing methods¶
The extension provides several types of hashing method:
- Portable PHP password hashing This method allows to exchange salted hashes with other CMS like Drupal or Wordpress as they support phpass too. This is the format of previously generated salted user passwords by extension t3sec_saltedpw. This method is derived from a third-party library. Portable PHP password hashing method is available in any environment, TYPO3 4.3 will run with. It’s the default and recommended setting. .
- MD5 salted hashing This method allows to use Salted user password hashes for other server daemon authentications (mailserver, etc.) too. Use this setting if you need to authenticate other services against TYPO3 user records. This method uses PHP standard capabilities.
- Blowfish salted hashing This method provides increased security in comparison to MD5 salted hashing. Use this setting if you have higher requirements on password security. You might want to execute the Unit Tests brought together with this extension; if tests in blowfish test suite fail, your server installation most probably does not support blowfish. Once you’ve chosen blowfish hashing, you need to make sure blowfish is available on the server you might move to in future. Otherwise, users won’t be able to login any longer.
- PBKDF2 key derivation This method provides increased security in comparison to MD5 salted hashing. Use this setting if you have higher requirements on password security. This requires a PHP > 5.5.0.
Due to the nature of salted user password hashes, the server needs to have a plain-text password to check against stored salted user password hashes of a database user record during authentication. This requires a transfer of the plain-text password from a user’s browser to the TYPO3 server.
You obviously want to send the password over an encrypted channel. According possibilities are the usage of either SSL with your web server or the TYPO3 system extension rsaauth.