How are web site passwords encrypted by browsers?

Question

What are some platform-specific API's that web browsers use to securely save passwords with reversible encryption on local systems?

Since they must be able to reproduce the exact characters to pass up to a web site, the data can't be a one-way hash. My initial thought is there are system methods which utilize your current authentication data to perform encryption/decryption, but do not give access to applications to read it (your system login data) directly. I'm wondering what these are on different platforms (Windows, Linux, OS X) and how well they protect the information if the hard drive is accessed directly; i.e. a stolen laptop hard drive is placed into another computer or analyzed via a Live CD.

Answer 1

Here's how google chrome does it. Looks like they use CryptProtectData on windows.