mirror of
https://github.com/XRPLF/rippled.git
synced 2026-09-02 15:19:21 +00:00
f45cce80e6
SHAMap::addKnownNode() reports invalid() for the two kinds of node it does not hook into the map: an inner node arriving at kLeafDepth, a depth only a leaf may occupy, and a node whose ID does not match the position the descent stopped at. That is the verdict callers already handle as bad data, so neither counts as forward progress. Each emits one warning naming the node and where the descent stopped, matching the sibling branches beside them, and carries a SOMETIMES() hint for the fuzzer. The depth rule is spelled once, as a file-local isLeafDepth() that hasLeafNode() reads too. The verdict on a map-invalidating node belongs to the root hash that was asked for rather than to this copy of the tree, since every node from the root down hash-verified to get there: no peer can satisfy such a hash, retrying is futile, and it cannot arise by accident. A charge for it is a deterrent rather than a control even so, which the comment says, because the same node can reach a map through a fetch pack or an unsolicited object reply and neither passes through here. The depth test precedes the full-below cache lookup on the way down. That cache is keyed by node hash and shared by every map of a family, and a hash covers a node's children but not its depth, so the same subtree hash can be cached as complete at one depth and reached at kLeafDepth here. Testing the depth first is what keeps the verdict independent of whatever an unrelated map cached, which is the determinism the acquisition paths need from it. Skipping the shortcut at the deepest level only forgoes an optimization, and the depth it guards cannot occur in a real tree. Three tests drive the map through DeepChain's fill() and addOffendingNode(), so a case names the position no valid tree can occupy without spelling out the descent. They cover the map-invalidating node; the three ways a node cannot be hooked anywhere while leaving the map sound; and the same offending node with a full-below entry already in place, so the depth test is what has to reach the verdict. A file-local tallyIs() reads each verdict as counts, which leaves get()'s wording pinned in one place rather than at every site with a verdict to check.