This commit implements most of BIP0143 by adding logic to implement the
new sighash calculation, signing, and additionally introduces the
HashCache optimization which eliminates the O(N^2) computational
complexity for the SIGHASH_ALL sighash type.
The HashCache struct is the equivalent to the existing SigCache struct,
but for caching the reusable midstate for transactions which are
spending segwitty outputs.
This commit modifies the logic within the block manager and service to
preferentially fetch transactions and blocks which include witness data
from fully upgraded peers.
Once the initial version handshake has completed, the server now tracks
which of the connected peers are witness enabled (they advertise
SFNodeWitness). From then on, if a peer is witness enabled, then btcd
will always request full witness data when fetching
transactions/blocks.
This commit modifies the base peer struct to ascertain when a peer is
able to understand the new witness encoding, and specify the peer’s
supported encoding explicitly before/after the version handshake.
This commit implements the new witness encoding/decoding for
transactions as specified by BIP0144. After segwit activation, a
special transaction encoding is used to signal to upgraded nodes that
the transaction being deserialized bares witness data. The prior
BtcEncode and BtcDecode methods have been extended to be aware of the
new signaling bytes and the encoding of witness data within
transactions.
Additionally, a new method has been added to calculate the “stripped
size” of a transaction/block which is defined as the size of a
transaction/block *excluding* any witness data.
This commit adds the new inventory types for segwit which are used by
the responder to explicitly request that transactions/blocks sent for a
particular inv hash should include all witness data.
This commit modifies the existing wire.Message interface to introduce a
new MessageEncoding variant which dictates the exact encoding to be
used when serializing and deserializing messages. Such an option is now
necessary due to the segwit soft-fork package, as btcd will need to be
able to optionally encode transactions/blocks without witness data to
un-upgraded peers.
Two new functions have been introduced: ReadMessageWithEncodingN and
WriteMessageWithEncodingN which wrap BtcDecode/BtcEncode with the
desired encoding format.
This commit introduces the new SFNodeWitness service bit which has been
added to the protocol as part of BIP0144. The new service bit allows
peers on the network to signal their acceptance and adherence to the
new rules defined as part of the segwit soft-fork package.
The IsBech32SegwitPrefix method takes a string prefix and
determines if it is a valid prefix for a Bech32 encoded segwit
address for any of the default or registered networks.
Version 0.15.0 of Bitcoin Core will include a new RPC command that will
allow us to obtain the amount of time (in seconds) that the server has
been running.
This modifies the goclean.sh script that is executed on Travis to
only run the tests without the race detector.
While it is nice to run the race detector on the tests, unfortunately
there is a limit to the number of goroutines that can be launched while
running it. Since Travis is now much slower than it once was, this
causes a ton of false positive failures.
This corrects the assertion in the decodeSpentTxOut function so it does
not improperly cause a panic when unwinding transactions during a reorg
under certain circumstances. In particular, the provided transaction
version that is passed when a stxo entry does not exist is now -1 in
order to properly distinguish it from the zero value.
It also updates the tests accordingly.
This was discovered by the reorg on testnet from block
00000000000018c58c2d2816f03dac327d975a18af6edf1a369df67ecddaf816 to
0000000000001c1161a367156465cc6226e9f862d9c585f94db5779fdf5455ff.
The btclog package has been changed to defining its own logging
interface (rather than seelog's) and provides a default implementation
for callers to use.
There are two primary advantages to the new logger implementation.
First, all log messages are created before the call returns. Compared
to seelog, this prevents data races when mutable variables are logged.
Second, the new logger does not implement any kind of artifical rate
limiting (what seelog refers to as "adaptive logging"). Log messages
are outputted as soon as possible and the application will appear to
perform much better when watching standard output.
Because log rotation is not a feature of the btclog logging
implementation, it is handled by the main package by importing a file
rotation package that provides an io.Reader interface for creating
output to a rotating file output. The rotator has been configured
with the same defaults that btcd previously used in the seelog config
(10MB file limits with maximum of 3 rolls) but now compresses newly
created roll files. Due to the high compressibility of log text, the
compressed files typically reduce to around 15-30% of the original
10MB file.
This slightly optimizes the NAF function by avoiding returning the
unused bit when there is not a carry.
It also adds a bunch of additional unit tests which I made while
debugging.
This modifies the normalize function of the internal field value to
both optimize it and address an issue where the reduction could
lead to an incorrect result with a small range of values. It also adds
tests to ensure the behavior is correct.
The following benchmark shows the relative speedups as a result of the
optimization on my system. In particular, the changes result in
approximately a 14% speedup in Normalize, which ultimately translates to
a 2% speedup in signature verifies.
benchmark old ns/op new ns/op delta
--------------------------------------------------------------------
BenchmarkAddJacobian 1364 1289 -5.50%
BenchmarkAddJacobianNotZOne 3150 3091 -1.87%
BenchmarkScalarBaseMult 134117 132816 -0.97%
BenchmarkScalarBaseMultLarge 135067 132966 -1.56%
BenchmarkScalarMult 411218 402217 -2.19%
BenchmarkSigVerify 671585 657833 -2.05%
BenchmarkFieldNormalize 36.0 31.0 -13.89%
The github markdown interpreter has been changed such that it no longer
allows spaces in between the brackets and parenthesis of links and now
requires a newline in between anchors and other formatting. This
updates all of the markdown files accordingly.
While here, it also corrects a couple of inconsistencies in some of the
README.md files.
This updates the GetNetworkInfoResult structure to include the latest
fields added to Core for compatibility purposes.
While here, also move the definitions of the subtypes for the result
before their use for consistency.
This changes the nonce generated to detect self connections over to use
pseudo randoms instead of a cryptographically random nonce.
There is really not a good reason for it to be cryptographically strong,
using the prng is much faster, and the prng also doesn't burn entropy.
This removes the field that tracks whether the version has been sent
since it is no longer used after the version negotiation was separated
from the main read and write code.
This commit modifies the existing block validation logic to examine the
current version bits state of the CSV soft-fork, enforcing the new
validation rules (BIPs 68, 112, and 113) accordingly based on the
current `ThesholdState`.
This commit publicly exports the CreateBlock function as it can be very
useful for generating blocks for tests. Additionally, the behavior of
the function has been modified slightly to build off of the genesis
block for the specified chain if the `prevBlock` paramter is nil.
This commit adds BIP-9 deployment parameters for all registered
networks for the CSV soft-fork package.
The mainnet and testnet parameters have been set in accordance to the
finalized BIPs.
For simnet, and the regression net, the activation date is back-dated
in order to allow signaling for the soft-fork at any time. Additionally
the expiration time for simnet and regrets has been set to
math.MaxInt64, meaning they’ll never expire.
Now that glide is used for version management and a specific commit of
the upstream repository can be locked it is no longer necessary to
maintain a fork of the package specifically to keep a stable dependency.
While here, update the glide dependency for btcutil as well since it was
switched to use the upstream path as well.
Invalid tokens: github had made some changes the past months, the old style is not rendering at all, so I fixed that for you.
Other contributors can do the same for all of the project's documents.
Thanks.
This modifies the goclean.sh script that is executed on Travis to
only run the tests once.
While it is nice to see coverage reports in the log, unfortunately it
appears that both the -race and -cover flags can't be used together, and
the tests have grown in complexity such that they are starting to get
close to TravisCI time limits.
This simplifies the code based on the recommendations of the gosimple
lint tool.
Also, it increases the deadline for the linters to run to 10 minutes and
reduces the number of threads that is uses. This is being done because
the Travis environment has become increasingly slower and it also seems
to be hampered by too many threads running concurrently.
This modifies the blockNode and BestState structs in the blockchain
package to store hashes directly instead of pointers to them and updates
callers to deal with the API change in the exported BestState struct.
In general, the preferred approach for hashes moving forward is to store
hash values in complex data structures, particularly those that will be
used for cache entries, and accept pointers to hashes in arguments to
functions.
Some of the reasoning behind making this change is:
- It is generally preferred to avoid storing pointers to data in cache
objects since doing so can easily lead to storing interior pointers
into other structs that then can't be GC'd
- Keeping the hash values directly in the block node provides better
cache locality
Since the code base is currently in the process of changing over to
decouple download and connection logic, but not all of the necessary
parts are updated yet, ensure blocks that are in the database, but do
not have an associated main chain block index entry, are treated as if
they do not exist for the purposes of chain connection and selection
logic.
This refactors the block index logic into a separate struct and
introduces an individual lock for it so it can be queried independent of
the chain lock.
This modifies the block node structure to include a couple of extra
fields needed to be able to reconstruct the block header from a node,
and exposes a new function from chain to fetch the block headers which
takes advantage of the new functionality to reconstruct the headers from
memory when possible. Finally, it updates both the p2p and RPC servers
to make use of the new function.
This is useful since many of the block header fields need to be kept in
order to form the block index anyways and storing the extra fields means
the database does not have to be consulted when headers are requested if
the associated node is still in memory.
The following timings show representative performance gains as measured
from one system:
new: Time to fetch 100000 headers: 59ms
old: Time to fetch 100000 headers: 4783ms
