a4bcd687c934d47aa3922334e97e579caf5f8124 Improve tests using statistics (John Newbery) f424d601e1b6870e20bc60f5ccba36d2e210377b Add logging and addr rate limiting statistics (Pieter Wuille) b4ece8a1cda69cc268d39d21bba59c51fa2fb9ed Functional tests for addr rate limiting (Pieter Wuille) 5648138f5949013331c017c740646e2f4013bc24 Randomize the order of addr processing (Pieter Wuille) 0d64b8f709b4655d8702f810d4876cd8d96ded82 Rate limit the processing of incoming addr messages (Pieter Wuille) Pull request description: The rate at which IP addresses are rumoured (through ADDR and ADDRV2 messages) on the network seems to vary from 0 for some non-participating nodes, to 0.005-0.025 addr/s for recent Bitcoin Core nodes. However, the current codebase will happily accept and process an effectively unbounded rate from attackers. There are measures to limit the influence attackers can have on the addrman database (bucket restrictions based on source IPs), but still - there is no need to permit them to feed us addresses at a rate that's orders of magnitude larger than what is common on the network today, especially as it will cause us to spam our peers too. This PR implements a [token bucket](https://en.wikipedia.org/wiki/Token_bucket) based rate limiter, allowing an average of 0.1 addr/s per connection, with bursts up to 1000 addresses at once. Whitelisted peers as well as responses to GETADDR requests are exempt from the limit. New connections start with 1 token, so as to not interfere with the common practice of peers' self-announcement. ACKs for top commit: laanwj: ACK a4bcd687c934d47aa3922334e97e579caf5f8124 vasild: ACK a4bcd687c934d47aa3922334e97e579caf5f8124 jnewbery: ACK a4bcd687c934d47aa3922334e97e579caf5f8124 jonatack: ACK a4bcd687c934d47aa3922334e97e579caf5f8124 Tree-SHA512: b757de76ad78a53035b622944c4213b29b3b55d3d98bf23585afa84bfba10808299d858649f92269a16abfa75eb4366ea047eae3216f7e2f6d3c455782a16bea
Bitcoin Core integration/staging tree
For an immediately usable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/.
Further information about Bitcoin Core is available in the doc folder.
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 read the original Bitcoin 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 (see doc/build-*.md
for instructions) and tested, but it is not guaranteed to be
completely stable. Tags are created
regularly from release branches to indicate new official, stable release versions of Bitcoin Core.
The https://github.com/bitcoin-core/gui repository is used exclusively for the development of the GUI. Its master branch is identical in all monotree repositories. Release branches and tags do not exist, so please do not fork that repository unless it is for development reasons.
The contribution workflow is described in CONTRIBUTING.md and useful hints for developers can be found in doc/developer-notes.md.
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.
These tests can be run (if the test dependencies are installed) with: test/functional/test_runner.py
The CI (Continuous Integration) systems make sure that every pull request is built for Windows, Linux, and macOS, 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.