https://datatracker.ietf.org/doc/html/draft-josefsson-tls-curve25519-06#appendix-A.2 gives the following as a secret key / public key combo:
S_a = 0x6A2CB91DA5FB77B12A99C0EB872F4CDF
4566B25172C1163C7DA518730A6D0770
P_a = 85 20 F0 09 89 30 A7 54 74 8B 7D DC B4 3E F7 5A
0D BF 3A 0D 26 38 1A F4 EB A4 A9 8E AA 9B 4E 6A
https://www.rfc-editor.org/rfc/rfc7748#section-6.1 gives another secret key / public key combo:
Alice's private key, a:
77076d0a7318a57d3c16c17251b26645df4c2f87ebc0992ab177fba51db92c2a
Alice's public key, X25519(a, 9):
8520f0098930a754748b7ddcb43ef75a0dbf3a0d26381af4eba4a98eaa9b4e6a
Note how the public key is the same for both but the secret key is not.
sodium_crypto_box _publickey_from_secretkey seems to concur with the RFC but not the IETF Draft:
My question is... what is the RFC doing that the draft is not?
I ask because I have an implementation that is giving me the correct public key from the secret key in the IETF Draft and I'm wanting to make it so that I can use that same implementation to get the public key from the secret key in the IETF RFC. But, more than that, I'm just curious.
Thanks!