[Feature Request] Search for public/private keypairs that use standard RFC 8032 formatting rather than Tor formatting

[yasuiniko]

Can this code be modified easily to search for non-Tor keypairs? C is not my strong suit and I haven't been able to decipher the code, but I can at least describe the desired modification.

If I understand correctly, there are a couple ways to represent the info (scalar a, key1 h, key2 A) needed to sign with ED25519. Tor designates (a, h) as its (priv, pub) keypair, and calculates A = a * G at sign-time, where G is the standard base point (a fixed known number). Many other implementations designate a different (priv, pub) keypair (seed, A), and calculate (a, h) = SHA512(seed) at sign-time.

I imagine the code currently uses this simplified algorithm:

1. Generate (seed, A) using some ed25519 library
2. Convert to the Tor keypair (a, h) = SHA512(seed)
3. Search public key h for the user-provided search prefixes

How hard would it be to allow the code to skip step 2 and search A instead of h for the search prefixes?

[yasuiniko]

oops this is a duplicate of #31 and you explained the difficulties and why you aren't working on it over there. closing this.