Merge pull request #1401 from TheBlueMatt/2022-02-0conf-round-two

[rust-lightning] / lightning / src / util / scid_utils.rs

diff --git a/lightning/src/util/scid_utils.rs b/lightning/src/util/scid_utils.rs
index 8552358c35ae8d8fe8532f66cd9346409405c2c5..676c303bfa8dc1384b404cfe355aa77d99990242 100644 (file)
--- a/lightning/src/util/scid_utils.rs
+++ b/lightning/src/util/scid_utils.rs
@@ -79,6 +79,10 @@ pub(crate) mod fake_scid {
        const MAX_NAMESPACES: u8 = 8; // We allocate 3 bits for the namespace identifier.
        const NAMESPACE_ID_BITMASK: u8 = 0b111;
 
+       const BLOCKS_PER_MONTH: u32 = 144 /* blocks per day */ * 30 /* days per month */;
+       pub(crate) const MAX_SCID_BLOCKS_FROM_NOW: u32 = BLOCKS_PER_MONTH;
+
+
        /// Fake scids are divided into namespaces, with each namespace having its own identifier between
        /// [0..7]. This allows us to identify what namespace a fake scid corresponds to upon HTLC
        /// receipt, and handle the HTLC accordingly. The namespace identifier is encrypted when encoded
@@ -100,7 +104,6 @@ pub(crate) mod fake_scid {
                        // Ensure we haven't created a namespace that doesn't fit into the 3 bits we've allocated for
                        // namespaces.
                        assert!((*self as u8) < MAX_NAMESPACES);
-                       const BLOCKS_PER_MONTH: u32 = 144 /* blocks per day */ * 30 /* days per month */;
                        let rand_bytes = keys_manager.get_secure_random_bytes();
 
                        let segwit_activation_height = segwit_activation_height(genesis_hash);
@@ -109,7 +112,7 @@ pub(crate) mod fake_scid {
                        // We want to ensure that this fake channel won't conflict with any transactions we haven't
                        // seen yet, in case `highest_seen_blockheight` is updated before we get full information
                        // about transactions confirmed in the given block.
-                       blocks_since_segwit_activation = blocks_since_segwit_activation.saturating_sub(BLOCKS_PER_MONTH);
+                       blocks_since_segwit_activation = blocks_since_segwit_activation.saturating_sub(MAX_SCID_BLOCKS_FROM_NOW);
 
                        let rand_for_height = u32::from_be_bytes(rand_bytes[..4].try_into().unwrap());
                        let fake_scid_height = segwit_activation_height + rand_for_height % (blocks_since_segwit_activation + 1);