02306cc915
ef501a63d9consensus: document merkle mutation root invariant (Lőrinc) Pull request description: **Problem:** `ComputeMerkleRoot`'s optional mutation flag and the reasoning behind its per-level check are undocumented, and the behavior is only exercised indirectly by merkle_test through random duplications and old-vs-new comparisons, so a refactor could silently change it, as the discussions in #22046 and #28430 illustrate. **Fix:** Document the flag on the function declaration, explain inside the inner loop why the mutation check runs at every tree level even after a duplicate is found, and add direct API coverage for the CVE-2012-2459 construction. **Coverage check:** Both `merkle_test` and the new `merkle_test_mutated_return_value` would fail under a refactor that stops the outer reduction once mutation is detected, e.g.: <details><summary>Hypothetical regression</summary> ```patch diff --git a/src/consensus/merkle.cpp b/src/consensus/merkle.cpp index dfa23cf897..40bc3f8efa 100644 --- a/src/consensus/merkle.cpp +++ b/src/consensus/merkle.cpp @@ -59,6 +59,7 @@ uint256 ComputeMerkleRoot(std::vector<uint256> hashes, bool* mutated) { if (hashes[pos] == hashes[pos + 1]) mutation = true; } } + if (mutation) break; if (hashes.size() & 1) { hashes.push_back(hashes.back()); } ``` </details> Fixes #28457 ACKs for top commit: optout21: reACKef501a63d9achow101: ACKef501a63d9w0xlt: reACKef501a63d9hodlinator: ACKef501a63d9Tree-SHA512: 5a54eed071079a0a37333d5ba7c2d8eb81ae318ee4c84e15e3c050198daea6282453d4f7727b75f7dab90696b3d9bc946b8b33e6456a7f190b2297c15aca390c
Bitcoin Core integration/staging tree
For an immediately usable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/.
What is Bitcoin Core?
Bitcoin Core connects to the Bitcoin peer-to-peer network to download and fully validate blocks and transactions. It also includes a wallet and graphical user interface, which can be optionally built.
Further information about Bitcoin Core is available in the doc folder.
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completely stable. Tags are created
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There are also regression and integration tests, written
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Translations
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