search

lightningnetwork / lightning-onion

Onion Routed Micropayments for the Lightning Network
MIT License
397 stars 126 forks source link

fix generateCipherStream, initialize nonce #3

Closed david415 closed 7 years ago

david415 commented 7 years ago

the nonce isn't set!? https://github.com/lightningnetwork/lightning-onion/blob/master/sphinx.go#L337-L338

perhaps you could argue that setting the nonce isn't strictly necessary?

Roasbeef commented 7 years ago

Technically, the nonce is set, just to an initial value of all zeroes.

A nonce of all zeros is permissible as each generated intermediate key is never re-used. Within packet generation/processing chacha20 is used as a CSPRNG to generate a stream of random bytes by running the cipher with a fixed-size byte slice of all zeroes as input. As a result, the nonce is never incremented.

david415 commented 7 years ago

ok sounds good. sorry for the noise.