Add threshold for disabling from_future_htlc#3293
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When funding a transaction using `from_future_htlc`, we are taking the risk that the remote node doesn't fulfill the corresponding HTLCs. If we detect that too many peers fail such HTLCs, this may indicate a bug on the wallet side, so we automatically disable `from_future_htlc` to limit our exposure. We also ensure that nodes that already had one suspicious payment are blacklisted for other payments. This issue can happen when wallet users use multiple devices in unsupported scenarios.
pm47
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Apr 17, 2026
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LGTM.
My only comment is that it is not possible to independently (e.g. from a monitoring/alert point of view) tell whether we are currently rejecting all otf fundings, as it becomes dependent from the configuration. I think it's acceptable and not worth adding more complexity.
pm47
approved these changes
Apr 17, 2026
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When funding a transaction using
from_future_htlc, we are taking the risk that the remote node doesn't fulfill the corresponding HTLCs. If we detect that too many peers fail such HTLCs, this may indicate a bug on the wallet side, so we automatically disablefrom_future_htlcto limit our exposure.We also ensure that nodes that already had one suspicious payment are blacklisted for other payments. This issue can happen when wallet users use multiple devices in unsupported scenarios.