David Wong

cryptologie.net

cryptography, security, and random thoughts

Hey! I'm David, cofounder of zkSecurity, research advisor at Archetype, and author of the Real-World Cryptography book. I was previously a cryptography architect of Mina at O(1) Labs, the security lead for Libra/Diem at Facebook, and a security engineer at the Cryptography Services of NCC Group. Welcome to my blog about cryptography, security, and other related topics.

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Using crypto to replace database access.

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A pretty fresh article on how you could use crypto to replace a lot of complicated schemes you might use on your website like password reset or mail confirmation:

https://neosmart.net/blog/2015/using-hmac-signatures-to-avoid-database-writes/

tl;dr: instead of creating a table for tokens, you could create the password reset url like this:

http://www.example.com/password_reset/?user=username&expires=15649848949849&[email protected]&token=

and at the place of the token you would put the output of a MAC. Checking the MAC again after receiving the url would confirm that YOU created that url and it has not been modified. Remember, MAC provides integrity and authentication. The author also provides a way to only render this usable once: use the original hashed password as a nonce.

suggested reads:
← back to all posts blog • 2015-02-16
currently reading:
Using crypto to replace database access.
02-16 blog
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Real-World Cryptography is available from Manning Publications.
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