This commit implements the new block validation rules as defined by
BIP0141. The new rules include the constraints that if a block has
transactions with witness data, then there MUST be a commitment within
the conies transaction to the root of a new merkle tree which commits
to the wtxid of all transactions. Additionally, rather than limiting
the size of a block by size in bytes, blocks are now limited by their
total weight unit. Similarly, a newly define “sig op cost” is now used
to limit the signature validation cost of transactions found within
blocks.
This modifies the NewMsgTx function to accept the transaction version as
a parameter and updates all callers.
The reason for this change is so the transaction version can be bumped
in wire without breaking existing tests and to provide the caller with
the flexibility to create the specific transaction version they desire.
This adds a full-blown testing infrastructure in order to test consensus
validation rules. It is built around the idea of dynamically generating
full blocks that target specific rules linked together to form a block
chain. In order to properly test the rules, each test instance starts
with a valid block that is then modified in the specific way needed to
test a specific rule.
Blocks which exercise following rules have been added for this initial
version. These tests were largely ported from the original Java-based
'official' block acceptance tests as well as some additional tests
available in the Core python port. It is expected that further tests
can be added over time as consensus rules change.
* Enough valid blocks to have a stable base of mature coinbases to spend
for futher tests
* Basic forking and chain reorganization
* Double spends on forks
* Too much proof-of-work coinbase (extending main chain, in block that
forces a reorg, and in a valid fork)
* Max and too many signature operations via various combinations of
OP_CHECKSIG, OP_MULTISIG, OP_CHECKSIGVERIFY, and OP_MULTISIGVERIFY
* Too many and max signature operations with offending sigop after
invalid data push
* Max and too many signature operations via pay-to-script-hash redeem
scripts
* Attempt to spend tx created on a different fork
* Attempt to spend immature coinbase (on main chain and fork)
* Max size block and block that exceeds the max size
* Children of rejected blocks are either orphans or rejected
* Coinbase script too small and too large
* Max length coinbase script
* Attempt to spend tx in blocks that failed to connect
* Valid non-coinbase tx in place of coinbase
* Block with no transactions
* Invalid proof-of-work
* Block with a timestamp too far in the future
* Invalid merkle root
* Invalid proof-of-work limit (bits header field)
* Negative proof-of-work limit (bits header field)
* Two coinbase transactions
* Duplicate transactions
* Spend from transaction that does not exist
* Timestamp exactly at and one second after the median time
* Blocks with same hash via merkle root tricks
* Spend from transaction index that is out of range
* Transaction that spends more that its inputs provide
* Transaction with same hash as an existing tx that has not been
fully spent (BIP0030)
* Non-final coinbase and non-coinbase txns
* Max size block with canonical encoding which exceeds max size with
non-canonical encoding
* Spend from transaction earlier in same block
* Spend from transaction later in same block
* Double spend transaction from earlier in same block
* Coinbase that pays more than subsidy + fees
* Coinbase that includes subsidy + fees
* Invalid opcode in dead execution path
* Reorganization of txns with OP_RETURN outputs
* Spend of an OP_RETURN output
* Transaction with multiple OP_RETURN outputs
* Large max-sized block reorganization test (disabled by default since
it takes a long time and a lot of memory to run)
Finally, the README.md files in the main and docs directories have been
updated to reflect the use of the new testing framework.
This is mostly a backport of some of the same modifications made in
Decred along with a few additional things cleaned up. In particular,
this updates the code to make use of the new chainhash package.
Also, since this required API changes anyways and the hash algorithm is
no longer tied specifically to SHA, all other functions throughout the
code base which had "Sha" in their name have been changed to Hash so
they are not incorrectly implying the hash algorithm.
The following is an overview of the changes:
- Remove the wire.ShaHash type
- Update all references to wire.ShaHash to the new chainhash.Hash type
- Rename the following functions and update all references:
- wire.BlockHeader.BlockSha -> BlockHash
- wire.MsgBlock.BlockSha -> BlockHash
- wire.MsgBlock.TxShas -> TxHashes
- wire.MsgTx.TxSha -> TxHash
- blockchain.ShaHashToBig -> HashToBig
- peer.ShaFunc -> peer.HashFunc
- Rename all variables that included sha in their name to include hash
instead
- Update for function name changes in other dependent packages such as
btcutil
- Update copyright dates on all modified files
- Update glide.lock file to use the required version of btcutil
This commit is the first stage of several that are planned to convert
the blockchain package into a concurrent safe package that will
ultimately allow support for multi-peer download and concurrent chain
processing. The goal is to update btcd proper after each step so it can
take advantage of the enhancements as they are developed.
In addition to the aforementioned benefit, this staged approach has been
chosen since it is absolutely critical to maintain consensus.
Separating the changes into several stages makes it easier for reviewers
to logically follow what is happening and therefore helps prevent
consensus bugs. Naturally there are significant automated tests to help
prevent consensus issues as well.
The main focus of this stage is to convert the blockchain package to use
the new database interface and implement the chain-related functionality
which it no longer handles. It also aims to improve efficiency in
various areas by making use of the new database and chain capabilities.
The following is an overview of the chain changes:
- Update to use the new database interface
- Add chain-related functionality that the old database used to handle
- Main chain structure and state
- Transaction spend tracking
- Implement a new pruned unspent transaction output (utxo) set
- Provides efficient direct access to the unspent transaction outputs
- Uses a domain specific compression algorithm that understands the
standard transaction scripts in order to significantly compress them
- Removes reliance on the transaction index and paves the way toward
eventually enabling block pruning
- Modify the New function to accept a Config struct instead of
inidividual parameters
- Replace the old TxStore type with a new UtxoViewpoint type that makes
use of the new pruned utxo set
- Convert code to treat the new UtxoViewpoint as a rolling view that is
used between connects and disconnects to improve efficiency
- Make best chain state always set when the chain instance is created
- Remove now unnecessary logic for dealing with unset best state
- Make all exported functions concurrent safe
- Currently using a single chain state lock as it provides a straight
forward and easy to review path forward however this can be improved
with more fine grained locking
- Optimize various cases where full blocks were being loaded when only
the header is needed to help reduce the I/O load
- Add the ability for callers to get a snapshot of the current best
chain stats in a concurrent safe fashion
- Does not block callers while new blocks are being processed
- Make error messages that reference transaction outputs consistently
use <transaction hash>:<output index>
- Introduce a new AssertError type an convert internal consistency
checks to use it
- Update tests and examples to reflect the changes
- Add a full suite of tests to ensure correct functionality of the new
code
The following is an overview of the btcd changes:
- Update to use the new database and chain interfaces
- Temporarily remove all code related to the transaction index
- Temporarily remove all code related to the address index
- Convert all code that uses transaction stores to use the new utxo
view
- Rework several calls that required the block manager for safe
concurrency to use the chain package directly now that it is
concurrent safe
- Change all calls to obtain the best hash to use the new best state
snapshot capability from the chain package
- Remove workaround for limits on fetching height ranges since the new
database interface no longer imposes them
- Correct the gettxout RPC handler to return the best chain hash as
opposed the hash the txout was found in
- Optimize various RPC handlers:
- Change several of the RPC handlers to use the new chain snapshot
capability to avoid needlessly loading data
- Update several handlers to use new functionality to avoid accessing
the block manager so they are able to return the data without
blocking when the server is busy processing blocks
- Update non-verbose getblock to avoid deserialization and
serialization overhead
- Update getblockheader to request the block height directly from
chain and only load the header
- Update getdifficulty to use the new cached data from chain
- Update getmininginfo to use the new cached data from chain
- Update non-verbose getrawtransaction to avoid deserialization and
serialization overhead
- Update gettxout to use the new utxo store versus loading
full transactions using the transaction index
The following is an overview of the utility changes:
- Update addblock to use the new database and chain interfaces
- Update findcheckpoint to use the new database and chain interfaces
- Remove the dropafter utility which is no longer supported
NOTE: The transaction index and address index will be reimplemented in
another commit.
This commit converts all block height references to int32 instead of
int64. The current target block production rate is 10 mins per block
which means it will take roughly 40,800 years to reach the maximum
height an int32 affords. Even if the target rate were lowered to one
block per minute, it would still take roughly another 4,080 years to
reach the maximum.
In the mean time, there is no reason to use a larger type which results
in higher memory and disk space usage. However, for now, in order to
avoid having to reserialize a bunch of database information, the heights
are still serialized to the database as 8-byte uint64s.
This is being mainly being done in preparation for further upcoming
infrastructure changes which will use the smaller and more efficient
4-byte serialization in the database as well.
This commit contains the entire btcchain repository along with several
changes needed to move all of the files into the blockchain directory in
order to prepare it for merging. This does NOT update btcd or any of the
other packages to use the new location as that will be done separately.
- All import paths in the old btcchain test files have been changed to
the new location
- All references to btcchain as the package name have been changed to
blockchain
