Derive secrets from commitment points #96
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| @@ -285,6 +297,14 @@ impl Privkey { | |||
| pub fn pubkey(&self) -> Pubkey { | |||
| Pubkey::from(self.0.public_key(secp256k1_instance())) | |||
| } | |||
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| pub fn tweak<I: Into<[u8; 32]>>(&self, scalar: I) -> Self { | |||
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Since you only need ref of [u8; 32], AsRef is better than Into here.
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The problem I encountered is that https://doc.rust-lang.org/std/convert/trait.AsRef.html#tymethod.as_ref AsRef<[u8; 32]> is not automatically implemented for [u8; 32]. The automatic implementation of the rust compiler only works without the length 32. https://doc.rust-lang.org/std/convert/trait.AsRef.html#impl-AsRef%3C%5BT%5D%3E-for-%5BT%5D
| // Normally commitment number will be incremented after received a RevokeAndAck message. | ||
| // But here channel has not been etablished yet, so we will not receive RevokeAndAck message. | ||
| // We increment the commitment number here instead. | ||
| state.increment_local_commitment_number(); |
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Could you explain why this is no longer needed?
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This commit has relevant information about this change. 11f710b. TLDR is that I moved the code to on_channel_ready function. It has to be delayed to there because incrementing these numbers too soon may cause problems.
| // Normally commitment number will be incremented after sent a RevokeAndAck message. | ||
| // But here channel has not been etablished yet, so we will not send RevokeAndAck message. | ||
| // We increment the commitment number here instead. | ||
| self.increment_remote_commitment_number(); |
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Could you explain why this is no longer needed?
Before current local commitment number change and channel ready, we actually use the commitment number to derive secrets. Changing the commitment number too soon will make the secrets derived from different parties different.
Fixes #63