Ask HN: Method for knowing if one-way-encrypted data is identical to another?
1Password does not provide functionality to sweep and remove all duplicates. The reason for that, it's not possible to compare encrypted entries, since it's using one-way encryption function. Meaning even two identical entries will have different signatures.
While there may be methods of working around with that, it is apparently engineering complexity barrier that they will not tackle. And they will not implement solution that will give 1Password too much access to the data either (to decrypt all with your key and tell which are duplicates). 1Password only sees encrypted data. The solution for comparing the duplicates has to be cryptographical.
My question to cryptography experts, when adding password entry to password database, can we generate some kind of hash to use later for comparing entries for being identical? Maybe hash unique within some special "seed", so we can compare entries encrypted with that seed. The algorithm/hash should satisfy requirement of not being reversible, and not open possibility to brute force cracking.
On a related note, almost every password manager including ones built into browsers and 1Password itself, all have "your password is too weak" recommendations. Does it mean they have that flag set at the time they encrypt the password?