The re-init is expensive, so skip it if there is no need.
Also, add an even faster fuzz target utxo_snapshot_invalid, which does
not need any re-init at all.
fa6fe43207 net: Clarify that m_addr_local is only set once (MarcoFalke)
Pull request description:
The function is supposed to be only called once when the version msg arrives (a single time). Calling it twice would be an internal logic bug. However, the `LogError` in this function has many issues:
* If the error happens in tests, as is the case for the buggy fuzz test, it will go unnoticed
* It is dead code, unless a bug is introduced to execute it
Fix all issues by using `Assume(!m_addr_local.IsValid())` instead. Idea taken from https://github.com/bitcoin/bitcoin/pull/30364#discussion_r1680530382
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Tree-SHA512: 8c1e8c524768f4f36cc50110ae54ee423e057a963ff78f736f3bf92df1ce5af28e3e0149153780897944e1d5c22ddbca9dac9865d9f4d44afffa152bc8559405
It is expensive to construct, and only one test uses it.
Fix both issues by disallowing the construction and moving it to the
single test that uses it.
86b38529d5 qa: a fuzz target for the block index database (Antoine Poinsot)
Pull request description:
This introduces a small fuzz target for `CBlockTreeDB` which asserts a few invariants by using an in-memory LevelDb.
ACKs for top commit:
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Tree-SHA512: ab75b4ae1c7e0a4b15f8a6ceffdf509fbc79833e6ea073ecef68558d53b83663d1b30362aaa2d77c22b8890a572f5b1d4b1c5abbca483c8c8f9b1fb5b276a59a
00618e8745 assumeutxo: Drop block height from metadata (Fabian Jahr)
Pull request description:
Fixes https://github.com/bitcoin/bitcoin/issues/30514 which has more context and shows how the issue can be reproduced. Since the value in question is removed, there is no test to add to reproduce anything.
This is an alternative approach to #30516 with much of the [code being suggested there](https://github.com/bitcoin/bitcoin/pull/30516#discussion_r1689146902).
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Tree-SHA512: db9575247bae838ad7742a27a216faaf55bb11e022f9afdd05752bb09bbf9614717d0ad64304ff5722a16bf41d8dea888af544e4ae26dcaa528c1add0269a4a8
2925bd537c refactor: use c++20 std::views::reverse instead of reverse_iterator.h (stickies-v)
Pull request description:
C++20 introduces [`std::ranges::views::reverse`](https://en.cppreference.com/w/cpp/ranges/reverse_view), which allows us to drop our own `reverse_iterator.h` implementation and also makes it easier to chain views (even though I think we currently don't use this).
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Tree-SHA512: 567666ec44af5d1beb7a271836bcc89c4c577abc77f522fcc18bc6d4de516ae9b0df766d0bfa6dd217569e6878331c2aee1d9815620860375e3510dad7fed476
589db872e1 validation: don't erase coins cache on prune flushes (Andrew Toth)
0e8918755f Add linked-list test to CCoinsViewCache::SanityCheck (Pieter Wuille)
05cf4e1875 coins: move Sync logic to CoinsViewCacheCursor (Andrew Toth)
7825b8b9ae coins: pass linked list of flagged entries to BatchWrite (Andrew Toth)
a14edada8a test: add cache entry linked list tests (Andrew Toth)
24ce37cb86 coins: track flagged cache entries in linked list (Andrew Toth)
58b7ed156d coins: call ClearFlags in CCoinsCacheEntry destructor (Andrew Toth)
8bd3959fea refactor: require self and sentinel parameters for AddFlags (Andrew Toth)
75f36d241d refactor: add CoinsCachePair alias (Andrew Toth)
f08faeade2 refactor: move flags to private uint8_t and rename to m_flags (Andrew Toth)
4e4fb4cbab refactor: disallow setting flags in CCoinsCacheEntry constructors (Andrew Toth)
8737c0cefa refactor: encapsulate flags setting with AddFlags and ClearFlags (Andrew Toth)
9715d3bf1e refactor: encapsulate flags get access for all other checks (Andrew Toth)
df34a94e57 refactor: encapsulate flags access for dirty and fresh checks (Andrew Toth)
Pull request description:
Since https://github.com/bitcoin/bitcoin/pull/17487 we no longer need to clear the coins cache when syncing to disk. A warm coins cache significantly speeds up block connection, and only needs to be fully flushed when nearing the `dbcache` limit.
For frequent pruning flushes there's no need to empty the cache and kill connect block speed. However, simply using `Sync` in place of `Flush` actually slows down a pruned full IBD with a high `dbcache` value. This is because as the cache grows, sync takes longer since every coin in the cache is scanned to check if it's dirty. For frequent prune flushes and a large cache this constant scanning starts to really slow IBD down, and just emptying the cache on every prune becomes faster.
To fix this, we can add two pointers to each cache entry and construct a doubly linked list of dirty entries. We can then only iterate through all dirty entries on each `Sync`, and simply clear the pointers after.
With this approach a full IBD with `dbcache=16384` and `prune=550` was 32% faster than master. For default `dbcache=450` speedup was ~9%. All benchmarks were run with `stopatheight=800000`.
| | prune | dbcache | time | max RSS | speedup |
|-----------:|----------:|------------:|--------:|-------------:|--------------:|
| master | 550 | 16384 | 8:52:57 | 2,417,464k | - |
| branch | 550 | 16384 | 6:01:00 | 16,216,736k | 32% |
| branch | 550 | 450 | 8:05:08 | 2,818,072k | 8.8% |
| master | 10000 | 5000 | 8:19:59 | 2,962,752k | - |
| branch | 10000 | 5000| 5:56:39 | 6,179,764k | 28.8% |
| master | 0 | 16384 | 4:51:53 | 14,726,408k | - |
| branch | 0 | 16384 | 4:43:11 | 16,526,348k | 2.7% |
| master | 0 | 450 | 7:08:07 | 3,005,892k | - |
| branch | 0 | 450 | 6:57:24 | 3,013,556k |2.6%|
While the 2 pointers add memory to each cache entry, it did not slow down IBD. For non-pruned IBD results were similar for this branch and master. When I performed the initial IBD, the full UTXO set could be held in memory when using the max `dbcache` value. For non-pruned IBD with max `dbcache` to tip ended up using 12% more memory, but it was also 2.7% faster somehow. For smaller `dbcache` values the `dbcache` limit is respected so does not consume more memory, and the potentially more frequent flushes were not significant enough to cause any slowdown.
For reviewers, the commits in order do the following:
First 4 commits encapsulate all accesses to `flags` on cache entries, and then the 5th makes `flags` private.
Commits `refactor: add CoinsCachePair alias` to `coins: call ClearFlags in CCoinsCacheEntry destructor` create the linked list head nodes and cache entry self references and pass them into `AddFlags`.
Commit `coins: track flagged cache entries in linked list` actually adds the entries into a linked list when they are flagged DIRTY or FRESH and removes them from the linked list when they are destroyed or the flags are cleared manually. However, the linked list is not yet used anywhere.
Commit `test: add cache entry linked list tests` adds unit tests for the linked list.
Commit `coins: pass linked list of flagged entries to BatchWrite` uses the linked list to iterate through DIRTY entries instead of using the entire coins cache.
Commit `validation: don't erase coins cache on prune flushes` uses `Sync` instead of `Flush` for pruning flushes, so the cache is no longer cleared.
Inspired by [this comment](https://github.com/bitcoin/bitcoin/pull/15265#issuecomment-457720636).
Fixes https://github.com/bitcoin/bitcoin/issues/11315.
ACKs for top commit:
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Tree-SHA512: 23b2bc01c83edacb5b39aa60bb0b766de9a74ce17f0c59bf13b97b4328a7b758ad9aff6581c3ca88e2973f7658380651530d497444f48d6e22ea0bfc51cc921d
6bfa26048d testnet: Add timewarp attack prevention for Testnet4 (Fabian Jahr)
0100907ca1 testnet: Add Testnet4 difficulty adjustment rules fix (Fabian Jahr)
74a04f9e7a testnet: Introduce Testnet4 (Fabian Jahr)
Pull request description:
To supplement the [ongoing conceptual discussion about a testnet reset](https://groups.google.com/g/bitcoindev/c/9bL00vRj7OU/m/9yCPo3uUBwAJ) I have drafted a move to v4 including a fix to the difficulty adjustment mechanism, which was part of the motivation that started the discussion.
Conceptual considerations:
- The conceptual discussion about doing a testnet4 or softforking the fix into testnet3 is outside of the scope of this PR and I would ask reviewers to contribute their opinions on this on the ML instead. However, I am happy to adapt this PR to a softfork change on testnet3 if there is consensus for that instead.
- The difficulty adjustment fix suggested here touches the `CalculateNextWorkRequired` function and uses the same logic used in `GetNextWorkRequired` to find the last previous block that was not mined with difficulty 1 under the exceptionf. An alternative fix briefly mentioned on the mailing list by Jameson Lopp would be to "restrict the special testnet minimum difficulty rule so that it can't be triggered on the block right before a difficulty retarget". That would also fix the issue but I find my suggestion here a bit more elegant.
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tACK 6bfa26048d
Tree-SHA512: 0b8b69a621406a944da5be551b863d065358ba94d85dd3b80d83c412660e230ee93b27316081fbee9b4851cc4ff8585db64c7dfa26cb5148ac835663f2712c3d
ec973dd197 refactor: remove un-tested early returns (josibake)
72a5822d43 tests: add tests for KeyPair (josibake)
cebb08b121 refactor: move SignSchnorr to KeyPair (josibake)
c39fd39ba8 crypto: add KeyPair wrapper class (josibake)
5d507a0091 tests: add key tweak smoke test (josibake)
f14900b6e4 bench: add benchmark for signing with a taptweak (josibake)
Pull request description:
Broken out from #28201
---
The wallet returns an untweaked internal key for taproot outputs. If the output commits to a tree of scripts, this key needs to be tweaked with the merkle root. Even if the output does not commit to a tree of scripts, BIP341/342 recommend commiting to a hash of the public key.
Previously, this logic for applying the taptweak was implemented in the `CKey::SignSchnorr` method.
This PR moves introduces a KeyPair class which wraps a `secp256k1_keypair` type and refactors SignSchnorr to use this new KeyPair. The KeyPair class is created with an optional merkle_root argument and the logic from BIP341 is applied depending on the state of the merkle_root argument.
The motivation for this refactor is to be able to use the tap tweak logic outside of signing, e.g. in silent payments when retrieving the private key (see #28201).
Outside of silent payments, since we almost always convert a `CKey` to a `secp256k1_keypair` when doing anything with taproot keys, it seems generally useful to have a way to model this type in our code base.
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Tree-SHA512: 34947e3eac39bd959807fa21b6045191fc80113bd650f6f08606e4bcd89aa17d6afd48dd034f6741ac4ff304b104fa8c1c1898e297467edcf262d5f97425da7b
6714276d72 miniscript: Use `ToIntegral` instead of `ParseInt64` (brunoerg)
Pull request description:
Currently, miniscript code uses `ParseInt64` function for `after`, `older`, `multi` and `thresh` fragments. It means that a leading `+` or whitespace, among other things, are accepted into the fragments. However, these cases are not useful and cause Bitcoin Core to behave differently compared to other miniscript implementations (see https://github.com/brunoerg/bitcoinfuzz/issues/34). This PR fixes it.
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utACK 6714276d72
Tree-SHA512: d9eeb93f380f346d636513eeaf26865285e7b0907b8ed258fe1e02153a9eb69d484c82180eb1c78b0ed77ad5f0e5b244be6672c2f890b1d9fddc9e844bee6dde
e9de0a76b9 doc: release note for 30212 (willcl-ark)
87b1880525 rpc: clarify ALREADY_IN_CHAIN rpc errors (willcl-ark)
Pull request description:
Closes: #19363
Renaming this error improves clarity around the returned error both internally and externally when a transactions' outputs are already found in the utxo set (`TransactionError::ALREADY_IN_CHAIN -> TransactionError::ALREADY_IN_UTXO_SET`)
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Code review ACK e9de0a76b9.
Tree-SHA512: 7d2617200909790340951fe56a241448f9ce511900777cb2a712e8b9c0778a27d1f912b460f82335844224f1abb4322bc898ca076440959edade55c082a09237
fa895c7283 mingw: Document mode wbx workaround (MarcoFalke)
fa359255fe Add -blocksxor boolean option (MarcoFalke)
fa7f7ac040 Return XOR AutoFile from BlockManager::Open*File() (MarcoFalke)
Pull request description:
Currently the *.dat files in the blocksdir store the data received from remote peers as-is. This may be problematic when a program other than Bitcoin Core tries to interpret them by accident. For example, an anti-virus program or other program may scan them and move them into quarantine, or delete them, or corrupt them. This may cause Bitcoin Core to fail a reorg, or fail to reply to block requests (via P2P, RPC, REST, ...).
Fix this, similar to https://github.com/bitcoin/bitcoin/pull/6650, by rolling a random XOR pattern over the dat files when writing or reading them.
Obviously this can only protect against programs that accidentally and unintentionally are trying to mess with the dat files. Any program that intentionally wants to mess with the dat files can still trivially do so.
The XOR pattern is only applied when the blocksdir is freshly created, and there is an option to disable it (on creation), so that people can disable it, if needed.
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Re-ACK fa895c7283
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ACK fa895c7283
Tree-SHA512: c92a6a717da83bc33a9b8671a779eeefde2c63b192362ba1d71e6535ee31d08e2802b74acc908345197de9daac6930e4771595ee25b09acd5a67f7ea34854720
172c1ad026 test: expand LimitOrphan and EraseForPeer coverage (Greg Sanders)
28dbe218fe refactor: move orphanage constants to header file (Greg Sanders)
Pull request description:
Inspired by refactorings in #30000 as the coverage appeared a bit sparse.
Added some minimal border value testing, timeouts, and tightened existing assertions.
ACKs for top commit:
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Tree-SHA512: e8fa9b1de6a8617612bbe9b132c9c0c9b5a651ec94fd8c91042a34a8c91c5f9fa7ec4175b47e2b97d1320d452c23775be671a9970613533e68e81937539a7d70
When using `sendrawtransaction` the ALREADY_IN_CHAIN error help string
may be confusing.
Rename TransactionError::ALREADY_IN_CHAIN to
TransactionError::ALREADY_IN_UTXO_SET and update the rpc help string.
Remove backwards compatibility alias as no longer required.
chainparams.cpp - workaround for MSVC bug triggering C7595 - Calling consteval constructors in initializer lists fails, but works on GCC (13.2.0) & Clang (17.0.6).
Complements uint256::FromHex() nicely in that it naturally does all error checking at compile time and so doesn't need to return an std::optional.
Will be used in the following 2 commits to replace many calls to uint256S(). uint256S() calls taking C-string literals are littered throughout the codebase and executed at runtime to perform parsing unless a given optimizer was surprisingly efficient. While this may not be a hot spot, it's better hygiene in C++20 to store the parsed data blob directly in the binary, without any parsing at runtime.
bf0efb4fc7 scripted-diff: Modernize naming of nChainTx and nTxCount (Fabian Jahr)
72e5d1be1f test: Add basic check for nChainTx type (Fabian Jahr)
dc2938e979 chainparams: Change nChainTx to uint64_t (Fabian Jahr)
Pull request description:
This picks up the work from #29331 and closes #29258.
This simply changes the type and addresses the comments from #29331 by changing the type in all relevant places and removing unnecessary casts. This also adds an extremely simple unit test.
Additionally this modernizes the name of `nChainTx` which helps reviewers check all use of the symbol and can make silent merge conflicts.
ACKs for top commit:
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reACK bf0efb4fc7 via range-diff
Tree-SHA512: ee4020926d0800236fe655d0c7b127215ab36b553b04d5f91494f4b7fac6e1cfe7ee298b07c0983db5a3f4786932acaa54f5fd2ccd45f2fcdcfa13427358dc3b
bbcee5a0d6 clusterlin: improve rechunking in LinearizationChunking (optimization) (Pieter Wuille)
04d7a04ea4 clusterlin: add MergeLinearizations function + fuzz test + benchmark (Pieter Wuille)
4f8958d756 clusterlin: add PostLinearize + benchmarks + fuzz tests (Pieter Wuille)
0e2812d293 clusterlin: add algorithms for connectedness/connected components (Pieter Wuille)
0e52728a2d clusterlin: rename Intersect -> IntersectPrefixes (Pieter Wuille)
Pull request description:
Part of cluster mempool: #30289
Depends on #30126, and was split off from it. #28676 depends on this.
This adds the algorithms for merging & postprocessing linearizations.
The `PostLinearize(depgraph, linearization)` function performs an in-place improvement of `linearization`, using two iterations of the [Linearization post-processing](https://delvingbitcoin.org/t/linearization-post-processing-o-n-2-fancy-chunking/201/8) algorithm. The first running from back to front, the second from front to back.
The `MergeLinearizations(depgraph, linearization1, linearization2)` function computes a new linearization for the provided cluster, given two existing linearizations for that cluster, which is at least as good as both inputs. The algorithm is described at a high level in [merging incomparable linearizations](https://delvingbitcoin.org/t/merging-incomparable-linearizations/209).
For background and references, see [Introduction to cluster linearization](https://delvingbitcoin.org/t/introduction-to-cluster-linearization/1032).
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Tree-SHA512: d2b5a3f132d1ef22ddf9c56421ab8b397efe45b3c4c705548dda56f5b39fe4b8f57a0d2a4c65b338462d80bb5b9b84a9a39efa1b4f390420a8005ce31817774e
73e3fa10b4 doc + test: Correct uint256 hex string endianness (Hodlinator)
Pull request description:
This PR is a follow-up to #30436.
Only changes test-code and modifies/adds comments.
Byte order of hex string representation was wrongfully documented as little-endian, but are in fact closer to "big-endian" (endianness is a memory-order concept rather than a numeric concept). `[arith_]uint256` both store their data in arrays with little-endian byte order (`arith_uint256` has host byte order within each `uint32_t` element).
**uint256_tests.cpp** - Avoid using variable from the left side of the condition in the right side. Credits to @maflcko: https://github.com/bitcoin/bitcoin/pull/30436#discussion_r1688273553
**setup_common.cpp** - Skip needless ArithToUint256-conversion. Credits to @stickies-v: https://github.com/bitcoin/bitcoin/pull/30436#discussion_r1688621638
---
<details>
<summary>
## Logical reasoning for endianness
</summary>
1. Comparing an `arith_uint256` (`base_uint<256>`) to a `uint64_t` compares the beginning of the array, and verifies the remaining elements are zero.
```C++
template <unsigned int BITS>
bool base_uint<BITS>::EqualTo(uint64_t b) const
{
for (int i = WIDTH - 1; i >= 2; i--) {
if (pn[i])
return false;
}
if (pn[1] != (b >> 32))
return false;
if (pn[0] != (b & 0xfffffffful))
return false;
return true;
}
```
...that is consistent with little endian ordering of the array.
2. They have the same endianness (but `arith_*` has host-ordering of each `uint32_t` element):
```C++
arith_uint256 UintToArith256(const uint256 &a)
{
arith_uint256 b;
for(int x=0; x<b.WIDTH; ++x)
b.pn[x] = ReadLE32(a.begin() + x*4);
return b;
}
```
### String conversions
The reversal of order which happens when converting hex-strings <=> uint256 means strings are actually closer to big-endian, see the end of `base_blob<BITS>::SetHexDeprecated`:
```C++
unsigned char* p1 = m_data.data();
unsigned char* pend = p1 + WIDTH;
while (digits > 0 && p1 < pend) {
*p1 = ::HexDigit(trimmed[--digits]);
if (digits > 0) {
*p1 |= ((unsigned char)::HexDigit(trimmed[--digits]) << 4);
p1++;
}
}
```
Same reversal here:
```C++
template <unsigned int BITS>
std::string base_blob<BITS>::GetHex() const
{
uint8_t m_data_rev[WIDTH];
for (int i = 0; i < WIDTH; ++i) {
m_data_rev[i] = m_data[WIDTH - 1 - i];
}
return HexStr(m_data_rev);
}
```
It now makes sense to me that `SetHexDeprecated`, upon receiving a shorter hex string that requires zero-padding, would pad as if the missing hex chars where towards the end of the little-endian byte array, as they are the most significant bytes. "Big-endian" string representation is also consistent with the case where `SetHexDeprecated` receives too many hex digits and discards the leftmost ones, as a form of integer narrowing takes place.
### How I got it wrong in #30436
Previously I used the less than (`<`) comparison to prove endianness, but for `uint256` it uses `memcmp` and thereby gives priority to the *lower* bytes at the beginning of the array.
```C++
constexpr int Compare(const base_blob& other) const { return std::memcmp(m_data.data(), other.m_data.data(), WIDTH); }
```
`arith_uint256` is different in that it begins by comparing the bytes from the end, as it is using little endian representation, where the bytes toward the end are more significant.
```C++
template <unsigned int BITS>
int base_uint<BITS>::CompareTo(const base_uint<BITS>& b) const
{
for (int i = WIDTH - 1; i >= 0; i--) {
if (pn[i] < b.pn[i])
return -1;
if (pn[i] > b.pn[i])
return 1;
}
return 0;
}
```
(The commit documents that `base_blob::Compare()` is doing lexicographic ordering unlike the `arith_*`-variant which is doing numeric ordering).
</details>
ACKs for top commit:
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Code review ACK 73e3fa10b4
Tree-SHA512: 121630c37ab01aa7f7097f10322ab37da3cbc0696a6bbdbf2bbd6db180dc5938c7ed91003aaa2df7cf4a4106f973f5118ba541b5e077cf3588aa641bbd528f4e
Follow-up to #30436.
uint256 string representation was wrongfully documented as little-endian due to them being reversed by GetHex() etc, and base_blob::Compare() giving most significance to the beginning of the internal array. They are closer to "big-endian", but this commit tries to be even more precise than that.
uint256_tests.cpp - Avoid using variable from the left side of the condition in the right side.
setup_common.cpp - Skip needless ArithToUint256-conversion.
Sanity check that using CKey/CPubKey directly vs using secp256k1_keypair objects
returns the same results for BIP341 key tweaking.
Co-authored-by: l0rinc <pap.lorinc@gmail.com>
75648cea5a test: add P2A ProduceSignature coverage (Greg Sanders)
7998ce6b20 Add release note for P2A output feature (Greg Sanders)
71c9b02a04 test: add P2A coverage for decodescript (Greg Sanders)
1349e9ec15 test: Add anchor mempool acceptance test (Greg Sanders)
9d89209937 policy: stop 3rd party wtxid malleability of anchor spend (Greg Sanders)
b60aaf8b23 policy: make anchor spend standard (Greg Sanders)
455fca86cf policy: Add OP_1 <0x4e73> as a standard output type (Greg Sanders)
Pull request description:
This is a sub-feature taken out of the original proposal for ephemeral anchors #30239
This PR makes *spending* of `OP_1 <0x4e73>` (i.e. `bc1pfeessrawgf`) standard. Creation of this output type is already standard.
Any future witness output types are considered relay-standard to create, but not to spend. This preserves upgrade hooks, such as a completely new output type for a softfork such as BIP341. It also gives us a bit of room to use a new output type for policy uses.
This particular sized witness program has no other known use-cases (https://bitcoin.stackexchange.com/a/110664/17078), s it affords insufficient cryptographic security for a secure commitment to data, such as a script or a public key. This makes this type of output "keyless", or unauthenticated.
As a witness program, the `scriptSig` of the input MUST be blank, by BIP141. This helps ensure txid-stability of the spending transaction, which may be required for smart contracting wallets. If we do not use segwit, a miner can simply insert an `OP_NOP` in the `scriptSig` without effecting the result of program execution.
An additional relay restriction is to disallow non-empty witness data, which an adversary may use to penalize the "honest" transactor when RBF'ing the transaction due to the incremental fee requirement of RBF rules.
The intended use-case for this output type is to "anchor" the transaction with a spending child to bring exogenous CPFP fees into the transaction package, encouraging the inclusion of the package in a block. The minimal size of creation and spending of this output makes it an attractive contrast to outputs like `p2sh(OP_TRUE)` and `p2wsh(OP_TRUE)` which
are significantly larger in vbyte terms.
Combined with TRUC transactions which limits the size of child transactions significantly, this is an attractive option for presigned transactions that need to be fee-bumped after the fact.
ACKs for top commit:
sdaftuar:
utACK 75648cea5a
theStack:
re-ACK 75648cea5a
ismaelsadeeq:
re-ACK 75648cea5a via [diff](e7ce6dc070..75648cea5a)
glozow:
ACK 75648cea5a
tdb3:
ACK 75648cea5a
Tree-SHA512: d529de23d20857e6cdb40fa611d0446b49989eaafed06c28280e8fd1897f1ed8d89a4eabbec1bbf8df3d319910066c3dbbba5a70a87ff0b2967d5205db32ad1e
