What's a good method/function to create a reversible hash?
I need to transmit some data over the wire and I don't want that data being plain text.
The text I'm sending needs to be reversed so I can't md5/sha256/etc...
What's a good way to encode a salted string?
You're looking for encryption.
What language are you using? You probably have a built-in encryption algorithm you can use.
The idea with hashing is that you can only go one-way.
[plain text]--->(HASH ALGORITHM)--->HASH
Whereas the idea with encryption is that you can use a key together with some plaintext to create a ciphertext. Then you can use the key on the ciphertext to retrieve the plaintext at any time:
[plain text] + [key] --->(ENCRYPTION ALGORITHM)-->[ciphertext] [ciphertext] + [key] --->(DECRYPTION ALGORITHM)-->[plain text]
The decryption algorithm for a given encryption algorithm is usually very similar to the encryption algorithm, and it allows for the retrieval of a plaintext message given a ciphertext and the correct key (ie password).
You want to use an encryption function, not a hash - which by definition is one-way.
The AES encryption algorithm would be a good start, as the is probably the most widely used one at present.
You don't want a hash, you want encryption. You should look at Blowfish.