Ask HN: Building a Meal Ministry App

2 points by bobblywobbles 5y ago ↗ HN

I'm looking to build a meal ministry application for people within a church community to come together and support one another in times of need.

Since I'd rather not build out a database of contact information that could be breachable in the future, I'd like to use Diffie-Hellman to ensure that only the people who have agreed to share a meal will send their contact information to each other. The encryption method seems within my reach, but due to each client having to save their private key, is this possible all within the browser?

Is localstorage, cookies, etc. a good option for saving the private key?

3 comments

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brodouevencode 5y ago ↗

Why not fetch on request? i.e.: when the transaction occurs then and only then do you pull from your data source and do what you need to do.

bobblywobbles 5y ago ↗

That's the intention, but for DH, the secret key needs to be stored on each client. My thought is the web browser needs to save the key locally in order that encryption/decryption can happen locally.

Not so sure DH is the optimal solution. Keeping secret keys untrusted is a bit of an anti-pattern.