This adds a new testnet3 network with new genesis block, block one
ledger, treasury address, and network magic.
All consensus rules that were voted in by testnet2 are automatically
active on the new testnet3 without having to vote them in again.
Consequently, there are no consensus vote agendas defined for it.
This change begins the work of bringing committed filters to the
network consensus daemon. Committed filters are designed to enable
light wallets without many of the privacy issues associated with
server-side bloom filtering.
The new gcs package provides the primitives for creating and matching
against Golomb-coded sets (GCS) filters while the blockcf package
provides creation of filters and filter entries for data structures
found in blocks.
The wire package has been updated to define a new protocol version and
service flag for advertising CF support and includes types for the
following new messages: cfheaders, cfilter, cftypes, getcfheaders,
getcfilter, getcftypes. The peer package and server implementation
have been updated to include support for the new protocol version and
messages.
Filters are created using a collision probability of 2^-20 and are
saved to a new optional database index when running with committed
filter support enabled (the default). At first startup, if support is
not disabled, the index will be created and populated with filters and
filter headers for all preexisting blocks, and new filters will be
recorded for processed blocks.
Multiple filter types are supported. The regular filter commits to
output scripts and previous outpoints that any non-voting wallet will
require access to. Scripts and previous outpoints that can only be
spent by votes and revocations are not committed to the filter. The
extended filter is a supplementary filter which commits to all
transaction hashes and script data pushes from the input scripts of
non-coinbase regular and ticket purchase transactions. Creating these
filters is based on the algorithm defined by BIP0158 but is modified
to only commit "regular" data in stake transactions to prevent
committed filters from being used to create SPV voting wallets.
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.
Putting the test code in the same package makes it easier for forks
since they don't have to change the import paths as much and it also
gets rid of the need for internal_test.go to bridge.
This same thing should probably be done for the majority of the code
base.
This sync includes a new service flag named SFNodeBloom that a node is
required to use to indicate that it supports bloom filtering. This
includes a protocol version bump to 2 and a wire version bump to 0.1.0.
dcrd:
The SFNodeBloom flag is set by default. A new configuration option
--nopeerbloomfilters has been added to to disable bloom filtering.
Also, it corrects an issue with the mining state message where it was
using the network protocol version instead of having its own version.
SFNodeBloom is a new service flag that a node is required to use to
indicate that it supports bloom filtering. This includes a protocol
version bump to 70011 and a wire version bump to 0.3.0.
btcd:
The SFNodeBloom flag is set by default. A new configuration option
--nopeerbloomfilters has been added to to disable bloom filtering.
Any node advertising a version greater than or equal to 70011 that
attempts to use bloom filtering will be disconnected if bloom
filtering is disabled.
This mimics Bitcoin Core commit afb0ccaf9c9e4e8fac7db3564c4e19c9218c6b03
This commit contains the entire btcwire repository along with several
changes needed to move all of the files into the wire 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 btcwire test files have been changed to the
new location
- All references to btcwire as the package name have been chagned to
wire
- The coveralls badge has been removed since it unfortunately doesn't
support coverage of sub-packages
This is ongoing work toward #214.
