37095c7dc4
385f5a4c3feb716fcf3f2b4823535df6da6bb67b p2p: Don't query DNS seeds when both IPv4 and IPv6 are unreachable (Martin Zumsande) 91f0a7fbb79fe81a75370a4b60dcdd2e55edfa81 p2p: add only reachable addresses to addrman (Martin Zumsande) Pull request description: Currently, `-onlynet` does not work well in connection with initial peer discovery, because DNS seeds only resolve to IPv6 and IPv4 adresses: With `-onlynet=i2p`, we would load clearnet addresses from DNS seeds into addrman, be content our addrman isn't empty so we don't try to query hardcoded seeds (although these exist for i2p!), and never attempt to make an automatic outbound connection. With `-onlynet=onion` and `-proxy` set, we wouldn't load addresses via DNS, but will make AddrFetch connections (through a tor exit node) to a random clearnet peer the DNS seed resolves to (see https://github.com/bitcoin/bitcoin/issues/6808#issuecomment-147652505), thus breaching the `-onlynet` preference of the user - this has been reported in the two issues listed below. This PR proposes two changes: 1.) Don't load addresses that are unreachable (so that we wouldn't connect to them) into addrman. This is already the case for addresses received via p2p addr messages, this PR implements the same for addresses received from DNS seeds and fixed seeds. This means that in the case of `-onlynet=onion`, we wouldn't load fixed seed IPv4 addresses into addrman, only the onion ones. 2.) Skip trying the DNS seeds if neither IPv4 nor IPv6 are reachable and move directly to adding the hardcoded seeds from networks we can connect to. This is done by soft-setting `-dnsseed` to 0 in this case, unless `-dnsseed=1` was explicitly specified, in which case we abort with an `InitError`. Fixes #6808 Fixes #12344 ACKs for top commit: naumenkogs: utACK 385f5a4c3feb716fcf3f2b4823535df6da6bb67b vasild: ACK 385f5a4c3feb716fcf3f2b4823535df6da6bb67b Tree-SHA512: 33a8c29faccb2d9b937b017dba4ef72c10e05e458ccf258f1aed3893bcc37c2e984ec8de998d2ecfa54282abbf44a132e97d98bbcc24a0dcf1871566016a9b91
Bitcoin Core integration/staging tree
For an immediately usable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/.
What is Bitcoin Core?
Bitcoin Core connects to the Bitcoin peer-to-peer network to download and fully validate blocks and transactions. It also includes a wallet and graphical user interface, which can be optionally built.
Further information about Bitcoin Core is available in the doc folder.
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.