Re^3: Eliminate server-side state to obviate cookies

Then you switch from needing to store a session ID in a database to needing to store and manage a private key. Not only that, but I can't imagine the ending size being less than the 160-bits needed for SHA1 (or 256 or 512 bits, if you want more secure hashes).

I'll continue looking for a solution that's better than cookies + secure ID + database.

"There is no shame in being self-taught, only in not trying to learn in the first place." -- Atrus, Myst: The Book of D'ni.

Comment on Re^3: Eliminate server-side state to obviate cookies

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Re^4: Eliminate server-side state to obviate cookies by tmoertel (Chaplain) on Jul 05, 2005 at 18:50 UTC
Why do you think it is so difficult? All you need is a single secret on the server. Then you can compute a signature as the hash of the secret plus the outgoing state plus a random salt. The signature, salt, and state are emitted in the response. When a request comes in, verify its signature by comparing it to the hash of the server's secret plus the client's salt and state. Easy as pie. If you're paranoid, you can add timestamps, rotate secrets, and use public-key signatures, none of which makes the job much more difficult. And, even if you do consider it more difficult, why does it matter for the day-to-day web programmer? This stuff is part of the web-app framework and invisible to end programmers. Cheers, Tom Tom Moertel : Blog / Talks / CPAN / LectroTest / PXSL / Coffee / Movie Rating Decoder	[reply]

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Re^4: Eliminate server-side state to obviate cookies
by tmoertel (Chaplain) on Jul 05, 2005 at 18:50 UTC

All you need is a single secret on the server. Then you can compute a signature as the hash of the secret plus the outgoing state plus a random salt. The signature, salt, and state are emitted in the response. When a request comes in, verify its signature by comparing it to the hash of the server's secret plus the client's salt and state.

Easy as pie.

If you're paranoid, you can add timestamps, rotate secrets, and use public-key signatures, none of which makes the job much more difficult. And, even if you do consider it more difficult, why does it matter for the day-to-day web programmer? This stuff is part of the web-app framework and invisible to end programmers.

Cheers,
Tom

Tom Moertel : Blog / Talks / CPAN / LectroTest / PXSL / Coffee / Movie Rating Decoder

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