Author: ZmnSCPxj 2020-03-24 08:27:27
Published on: 2020-03-24T08:27:27+00:00
In a conversation between ZmnSCPxj and Subhra, ZmnSCPxj discusses an issue regarding the LND protocol. ZmnSCPxj explains that A and B form an HTLC where the payment is "irrevocably committed". B then looks at the HTLC data and checks whether it knows the preimage to the payment hash. If B does not know the preimage, and there is no forwarding data (B is the final hop), then B responds with "incorrect or unknown payment details", and A waits for the channel state to advance. ZmnSCPxj also mentions that money gets locked temporarily in the HTLC but was freed soon afterwards as fast as B and A can advance the channel state. When asked how one can mimic a griefing attack scenario in LND, ZmnSCPxj suggests modifying the LND code directly or asking LND developers for any available hooks. In C-Lightning, a plugin must be installed, and you may devise some way for the plugin to know what payment hash you want to grief. Then, the plugin hooks into `htlc_accepted` handler, performs a `waitblockheight` command, and waits for the target block height to grief for before returning from the `htlc_accepted` handler.
Updated on: 2023-06-03T00:12:58.649978+00:00