The goal of this API is to make it easy to use and misuse resistant. The bulk of the code using this API can be reused. With the only difference being the start() call and getting the server secret at the end when registering. When registering, the server passes a null/empty secret to start() since it doesn't have one yet. Also start() might not return a message. This is fine. It just means the other party sends the first message.
PAKE_USER_CLIENT
PAKE_USER_SERVER
PAKE_USER_A
| CPace (defined on multiplicative groups) | |
| CPace is the best balanced PAKE that I know of. CPace defined on ECC can be | |
| found here: | |
| https://gist.github.com/Sc00bz/545eb39a369b67242634bd9c3302627c | |
| Costs per step | |
| A: - *^^ | |
| B: *^ ^ |
| # Related to https://abyssdomain.expert/@filippo/109925743627302756 | |
| # // len(z) == len(x)... or len(z) <= len(x) and everything is based on len(z) | |
| # // z[] += x[] * y | |
| # // c = overflow (ie c is "z[len(z)]") | |
| # func addMulVVW(z, x []uint, y uint) (c uint) | |
| # { | |
| lea RSI,[x] # RSI = "&x" | |
| lea RDI,[z] # RDI = "&z" |
| BS-SPEKE (defined on multiplicative groups) | |
| BS-SPEKE is a modified B-SPEKE with blind salt (OPRF). Modified B-SPEKE is a | |
| similar change from SPEKE as from SPAKE2 to SPAKE2+ to make it augmented. Doing | |
| this saves a scalar point multiply vs original B-SPEKE with blind salt. BS-SPEKE | |
| is the best augmented PAKE that I know of. Only problem is there are no proofs, | |
| but it's not hard to take the SPEKE proof, add the OPAQUE proof for OPRF, and | |
| it's obvious that the augmented change makes it augmented. So if anyone knows | |
| how to formally state that in a proof, that would be awesome to have. BS-SPEKE | |
| defined on ECC can be found here: |
| Double BS-SPEKE | |
| Double BS-SPEKE is BS-SPEKE but with 3DH vs Noise-KN to make it a doubly | |
| augmented PAKE. Double BS-SPEKE is the best doubly augmented PAKE that I know | |
| of. Only problem is there are no proofs, but it's not hard to take the SPEKE | |
| proof, add the OPAQUE proof for OPRF, and it's obvious that the doubly augmented | |
| change makes it doubly augmented. So if anyone knows how to formally state that | |
| in a proof, that would be awesome to have. BS-SPEKE defined on multiplicative | |
| groups can be found here: | |
| https://gist.github.com/Sc00bz/ec1f5fcfd18533bf0d6bf31d1211d4b4 |