fix(spv): align deposit sweep proof length with Bridge accumulated difficulty#3918
fix(spv): align deposit sweep proof length with Bridge accumulated difficulty#3918lionakhnazarov wants to merge 10 commits intothreshold-network:mainfrom
Conversation
- Added function to create block headers with specified difficulty. - Introduced method in to add headers for a range of heights based on dynamic difficulty. - Updated tests in to utilize the new difficulty handling, ensuring accurate proof range calculations across epochs. - Enhanced function to compute required confirmations based on actual header difficulties instead of fixed assumptions.
lrsaturnino
left a comment
lrsaturnino
left a comment
There was a problem hiding this comment.
Nice one! Just a couple of nits...
| requestedDiff = currentEpochDifficulty | ||
| case firstHeaderDiff.Cmp(previousEpochDifficulty) == 0: | ||
| requestedDiff = previousEpochDifficulty | ||
| default: |
There was a problem hiding this comment.
The default branch here silently returns false, which makes the caller log "proof goes outside the previous and current difficulty epochs" — but the real issue is the tx block was mined at min-difficulty.
On testnet4 this will cause silent retries with a misleading log. Could you add a logger.Warnf distinguishing this case? Something like "transaction block difficulty %s matches neither current (%s) nor previous (%s) epoch — may be unprovable if mined in a min-difficulty block."
There was a problem hiding this comment.
Missing a test for the scenario that motivated this whole PR — a tx block at min-difficulty where firstHeaderDiff matches neither epoch difficulty. Would be good to add a case with difficultyAtBlock(proofStartBlock) = big.NewInt(1) while epoch difficulties are much higher, expecting isProofWithinRelayRange=false.
2 participants
Updates the SPV maintainer’s getProofInfo logic so the number of Bitcoin headers in the SPV proof matches what Bridge.evaluateProofDifficulty requires: sum of per-header difficulty ≥ requestedDifficulty × txProofDifficultyFactor, with the first header matching relay current or previous epoch difficulty. Adds relay-window checks so the proof range stays in the previous epoch, current epoch, or spans previous→current only.
This fixes failures like Insufficient accumulated difficulty in header chain on chains where per-block work varies (e.g. testnet4 min-difficulty streaks), where a fixed block count × epoch-average math was wrong.
Changes
pkg/maintainer/spv/spv.go: implement proofRangeWithinRelayWindow; rewrite getProofInfo to walk headers from proof start, sum header.Difficulty(), resolve requestedDiff from first header vs relay difficulties.
pkg/maintainer/spv/spv_test.go + bitcoin_chain_test.go: populate mock headers with realistic Bits/difficulty; fix setCurrentAndPrevEpochDifficulty argument order; update expectations.
(if included) .github/workflows/contracts-ecdsa.yml: resolve accidental merge conflict markers in on: triggers.