silverstripe-framework: RFC: Deprecate and warn against using bad PasswordEncyptors

Affected Version

4.3.x / 5.0

Description

Currently we have several terrible options for password hashing:

• MySQLOldPassword
• MySQLPassword
• None
• PhpHash
• PhpLegacyHash

The MySQL “old” option is awful, and can be reversed with ~50 lines of C code, and the “new” version doesn’t seem to hold up to much scrutiny either.

I have no idea why we offer a “none” option. We should never encourage this.

PHPHash (and the extension LegacyHash) uses PHPs hash function. This is not suitable to password hashing purposes - these hashes are designed for efficiency - the opposite of what you want for passwords.

All of those are insufficient methods for hashing passwords.

Proposal

We mark all these "encryptor"s (hashers) as deprecated and show a warning (in dev mode? Only while logged in as admin?) if they are being used.