73db95c65c kernel: Make bitcoin-chainstate's block validation mirror submitblock's (TheCharlatan)
bb53ce9bda tests: Add functional test for submitting a previously pruned block (Greg Sanders)
1f7fc73825 rpc: Remove submitblock duplicate pre-check (TheCharlatan)
e62a8abd7d rpc: Remove submitblock invalid-duplicate precheck (TheCharlatan)
36dbebafb9 rpc: Remove submitblock coinbase pre-check (TheCharlatan)
Pull request description:
With the introduction of a mining ipc interface and the potential future introduction of a kernel library API it becomes increasingly important to offer common behaviour between them. An example of this is ProcessNewBlock, which is used by ipc, rpc, net_processing and (potentially) the kernel library. Having divergent behaviour on suggested pre-checks and checks for these functions is confusing to both developers and users and is a maintenance burden.
The rpc interface for ProcessNewBlock (submitblock) currently pre-checks if the block has a coinbase transaction and whether it has been processed before. While the current example binary for how to use the kernel library, bitcoin-chainstate, imitates these checks, the other interfaces do not.
The coinbase check is repeated again early during ProcessNewBlock. Pre-checking it may also shadow more fundamental problems with a block. In most cases the block header is checked first, before validating the transactions. Checking the coinbase first therefore masks potential issues with the header. Fix this by removing the pre-check.
Similary the duplicate checks are repeated early in the contextual checks of ProcessNewBlock. If duplicate blocks are detected much of their validation is skipped. Depending on the constitution of the block, validating the merkle root of the block is part of the more intensive workload when validating a block. This could be an argument for moving the pre-checks into block processing. In net_processing this would have a smaller effect however, since the block mutation check, which also validates the merkle root, is done before.
Testing spamming a node with valid, but duplicate unrequested blocks seems to exhaust a CPU thread, but does not seem to significantly impact keeping up with the tip. The benefits of adding these checks to net_processing are questionable, especially since there are other ways to trigger the more CPU-intensive checks without submitting a duplicate block. Since these DOS concerns apply even less to the RPC interface, which does not have banning mechanics built in, remove them too.
Finally, also remove the pre-checks from `bitcoin-chainstate.cpp`.
---
This PR is part of the [libbitcoinkernel project](https://github.com/bitcoin/bitcoin/issues/27587).
ACKs for top commit:
Sjors:
re-utACK 73db95c65c
achow101:
ACK 73db95c65c
instagibbs:
ACK 73db95c65c
mzumsande:
ACK 73db95c65c
Tree-SHA512: 2d02e851cf402ecf6a1968c058df3576aac407e200cbf922a1a6391b7f97b4f42c6d9f6b0a78b9d1af0a6d40bdd529a7b11a1e6d88885bd7b8b090f6d1411861
This tests the new submitblock behaviour that is introduced in the
previous commit: Submitting a previously pruned block should persist the
block's data again.
The coinbase check is repeated again early during ProcessNewBlock.
Pre-checking it may also shadow more fundamental problems with a block.
In most cases the block header is checked first, before validating the
transactions. Checking the coinbase first therefore masks potential
issues with the header. Fix this by removing the pre-check.
The pre-check was likely introduced on top of
ada0caa165 to fix UB in
GetWitnessCommitmentIndex in case a block's transactions are empty. This
code path could only be reached because of the call to
UpdateUncommittedBlockStructures in submitblock, but cannot be reached
through net_processing.
Add some functional test cases to cover the previous conditions that
lead to a "Block does not start with a coinbase" json rpc error being
returned.
---
With the introduction of a mining ipc interface and the potential future
introduction of a kernel library API it becomes increasingly important
to offer common behaviour between them. An example of this is
ProcessNewBlock, which is used by ipc, rpc, net_processing and
(potentially) the kernel library. Having divergent behaviour on
suggested pre-checks and checks for these functions is confusing to both
developers and users and is a maintenance burden.
The rpc interface for ProcessNewBlock (submitblock) currently pre-checks
if the block has a coinbase transaction and whether it has been
processed before. While the current example binary for how to use the
kernel library, bitcoin-chainstate, imitates these checks, the other
interfaces do not.
The added regtest option -test=bip94 is only used in the functional
test for BIP94.
This is done because the default regtest consensus rules
should aim to follow to mainnet, not testnet.
Previously, `wait_for_getheaders` would check whether a node had received **any**
getheaders message. This implied that, if a test needed to check for a specific block
hash within a headers message, it had to make sure that it was checking the desired message.
This normally involved having to manually clear `last_message`. This method, apart from being
too verbose, was error prone, given an undesired `getheaders` would make tests pass.
This adds the ability to check for a specific block_hash within the last `getheaders` message.
Included a test that checks if we call submitblock with
block.vtx.empty() then it throws an rpc deserialization error, currently
we only test if !block.vtx->IsCoinBase() throws an rpc deserialization
error
The previous diff touched most files in ./test/, so bump the headers to
avoid having to touch them again for a bump later.
-BEGIN VERIFY SCRIPT-
./contrib/devtools/copyright_header.py update ./test/
-END VERIFY SCRIPT-
Use object returned from add_p2p_connection to refer to
p2ps. Add a test class attribute if it needs to be used across
many methods. Don't use the p2p property.
Migrates the CScriptNum decode tests into a unit test, and moved some
changes made in #14816. Made possible by the integration of
test_framework unit testing in #18576. Further extends the original
test with larger ints, similar to the scriptnum_tests.cpp file. Adds
test to blocktools.py testing fn create_coinbase() with CScriptNum
decode.
1abcecc40c Tests: Use self.chain instead of 'regtest' in almost all current tests (Jorge Timón)
Pull request description:
Simply avoiding the hardcoded string in more places for consistency.
It can also allow for more easily reusing tests for other chains other than regtest.
Separated from #8994 .
Continues #16509 .
It is still not complete (ie to be complete, we need the -chain parameter in #16680 and make whether acceptnonstdtxs is allowed for that chain or not customizable for regtest [or for custom chains like in #8994 ] ). But while being incomplete like #16509 , it's quite simple to review and another step forward IMO.
ACKs for top commit:
Sjors:
re-ACK 1abcecc. I think it's an improvement even if incomplete and if some PR's might accidentally bring "regtest" back. Subsequent improvements hopefully don't have to touch 16 files.
elichai:
Code review ACK 1abcecc40c
ryanofsky:
Code review ACK 1abcecc40c.
ryanofsky:
Code review ACK 1abcecc40c
Tree-SHA512: 5620de6dab235ca8bd8670d6366c7b9f04f0e3ca9c5e7f87765b38e16ed80c17d7d1630c0d5fd7c5526f070830d94dc74cc2096d8ede87dc7180ed20569509ee
fa178a6385 [rpc] mining: Omit uninitialized currentblockweight, currentblocktx (MarcoFalke)
Pull request description:
Previously we'd report "0", which could be mistaken for a valid number. E.g. the number of transactions is 0 or the block weight is 0, whatever that means.
Tree-SHA512: ee94ab203a329e272211b726f4c23edec4b09c650ec363b77fd59ad9264165d73064f78ebb9e11b5c2c543b73c157752410a307655560531c7d5444d203aa0ea
Calling getblocktemplate without the segwit rule specified is most
likely a client error, since it results in lower fees for the miner.
Prevent this client error by failing getblocktemplate if called without
the segwit rule specified.
fa6ab8ada1 rpc: Return more specific reject reason for submitblock (MarcoFalke)
Pull request description:
The second commit in #13439 made the `TODO` in the first commit impossible to solve.
The meaning of `fNewBlock` changed from "This is the first time we process this block" to "We are about to write the new *valid* block".
So whenever `fNewBlock` is true, the block was valid. And whenever the `fNewBlock` is false, the block is either valid or invalid. If it was valid and not new, we know it is a `"duplicate"`. In all other cases, the `BIP22ValidationResult()` will return the reason why it is invalid.
Tree-SHA512: 4b6edf7a912339c3acb0fccfabbdd6d812a0321fb1639c244c2714e58dc119aa2b8c6bf8f7d61ea609a1b861bbc23f920370fcf989c48452721e259a8ce93d24
