4 ms·
Doesn't work, because you can reasonably brute-force possible gifts.
by garaetjjte 4y ago
Doesn't work, because you can reasonably brute-force possible gifts.
- Liron 4y agoYeah I'm not sure what's the best protocol that's actually zero-knowledge here, but since we both trusted each other to only want to find out whether or not our gifts were the same, and otherwise to not spoil the surprise, this did the job.
- kevinventullo 4y agoYou could write a script that does the hash comparison for you and simply outputs “Yes” or “No” for whether the hashes are identical.
- soonerroadie 4y agoYou could just write a script that lets you write an input and your spouse writes an input and then compares the two inputs without showing them - no need for hashing at all.
- lights0123 4y agoYou could reveal the hash letter-by-letter and stop as soon as a letter differs so there's more possibilities.
- teaearlgraycold 4y ago> stop as soon as a letter differs Oops - you just exposed a timing attack side channel
- mbauman 4y agoYou can similarly brute force mutual acquaintances in TFA
- 10000truths 4y agoSure, but the example is contrived, as it serves to illustrate the point in an easily digestible (heh) way. In real world applications, both the possible messages and the possible hashes would be way too large to brute force.
- xigoi 4y agoBut why would you do it?
- kjeetgill 4y agoI think the point is just that this is a misleading example of zero-knowledge proofs which are meaningful different cryptographically.