e065249 Add unit test for outbound peer eviction (Suhas Daftuar) 5a6d00c Permit disconnection of outbound peers on bad/slow chains (Suhas Daftuar) c60fd71 Disconnecting from bad outbound peers in IBD (Suhas Daftuar) Pull request description: The first commit will disconnect an outbound peer that serves us a headers chain with insufficient work while we're in IBD. The second commit introduces a way to disconnect outbound peers whose chains fall out of sync with ours: For a given outbound peer, we check whether their best known block (which is known from the blocks they announce to us) has at least as much work as our tip. If it doesn't, we set a 20 minute timeout, and if we still haven't heard about a block with as much work as our tip had when we set the timeout, then we send a single getheaders message, and wait 2 more minutes. If after two minutes their best known block has insufficient work, we disconnect that peer. We protect 4 of our outbound peers (who provide some "good" headers chains, ie a chain with at least as much work as our tip at some point) from being subject to this logic, to prevent excessive network topology changes as a result of this algorithm, while still ensuring that we have a reasonable number of nodes not known to be on bogus chains. We also don't require our peers to be on the same chain as us, to prevent accidental partitioning of the network in the event of a chain split. Note that if our peers are ever on a more work chain than our tip, then we will download and validate it, and then either reorg to it, or learn of a consensus incompatibility with that peer and disconnect. This PR is designed to protect against peers that are on a less work chain which we may never try to download and validate. Tree-SHA512: 2e0169a1dd8a7fb95980573ac4a201924bffdd724c19afcab5efcef076fdbe1f2cec7dc5f5d7e0a6327216f56d3828884f73642e00c8534b56ec2bb4c854a656
Bitcoin Core integration/staging tree
What is Bitcoin?
Bitcoin is an experimental digital currency that enables instant payments to anyone, anywhere in the world. Bitcoin uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the network. Bitcoin Core is the name of open source software which enables the use of this currency.
For more information, as well as an immediately useable, binary version of the Bitcoin Core software, see https://bitcoin.org/en/download, or read the original whitepaper.
License
Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/licenses/MIT.
Development Process
The master
branch is regularly built and tested, but is not guaranteed to be
completely stable. Tags are created
regularly to indicate new official, stable release versions of Bitcoin Core.
The contribution workflow is described in CONTRIBUTING.md.
The developer mailing list should be used to discuss complicated or controversial changes before working on a patch set.
Developer IRC can be found on Freenode at #bitcoin-core-dev.
Testing
Testing and code review is the bottleneck for development; we get more pull requests than we can review and test on short notice. Please be patient and help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.
Automated Testing
Developers are strongly encouraged to write unit tests for new code, and to
submit new unit tests for old code. Unit tests can be compiled and run
(assuming they weren't disabled in configure) with: make check
. Further details on running
and extending unit tests can be found in /src/test/README.md.
There are also regression and integration tests, written
in Python, that are run automatically on the build server.
These tests can be run (if the test dependencies are installed) with: test/functional/test_runner.py
The Travis CI system makes sure that every pull request is built for Windows, Linux, and OS X, and that unit/sanity tests are run automatically.
Manual Quality Assurance (QA) Testing
Changes should be tested by somebody other than the developer who wrote the code. This is especially important for large or high-risk changes. It is useful to add a test plan to the pull request description if testing the changes is not straightforward.
Translations
Changes to translations as well as new translations can be submitted to Bitcoin Core's Transifex page.
Translations are periodically pulled from Transifex and merged into the git repository. See the translation process for details on how this works.
Important: We do not accept translation changes as GitHub pull requests because the next pull from Transifex would automatically overwrite them again.
Translators should also subscribe to the mailing list.