1fa6411dde
8a3b6f3387refactor: make Transport::ReceivedBytes just return success/fail (Pieter Wuille)bb4aab90fdnet: move message conversion to wire bytes from PushMessage to SocketSendData (Pieter Wuille)a1a1060fd6net: measure send buffer fullness based on memory usage (Pieter Wuille)009ff8d650fuzz: add bidirectional fragmented transport test (Pieter Wuille)fb2c5edb79net: make V1Transport implicitly use current chainparams (Pieter Wuille)0de48fe858net: abstract sending side of transport serialization further (Pieter Wuille)649a83c7f7refactor: rename Transport class receive functions (Pieter Wuille)27f9ba23efnet: add V1Transport lock protecting receive state (Pieter Wuille)93594e42c3refactor: merge transport serializer and deserializer into Transport class (Pieter Wuille) Pull request description: This PR furthers the P2P message serialization/deserialization abstraction introduced in #16202 and #16562, in preparation for introducing the BIP324 v2 transport (making this part of #27634). However, nothing in this PR is BIP324-specific, and it contains a number of independently useful improvements. The overall idea is to have a single object in every `CNode` (called `m_transport`) that is responsible for converting sent messages to wire bytes, and for converting received wire bytes back to messages, while having as little as possible knowledge about this conversion process in higher-level net code. To accomplish that, there is an abstract `Transport` class with (currently) a single `V1Transport` implementation. Structurally, the above is accomplished by: * Merging the `TransportDeserializer` and `TransportSerializer` classes into a single `Transport` class, which encompasses both the sending and receiving side. For `V1Transport` these two sides are entirely separate, but this assumption doesn't hold for the BIP324 transport where e.g. the sending encryption key depends on the DH key negotiation data received from the other side. Merging the two means a future `V2Transport` can handle all this interaction without callers needing to be aware. * Removing the assumption that each message is sent using a computed header followed by (unmodified) data bytes. To achieve that, the sending side of `Transport` mirrors what the receiver side does: callers can set a message to be sent, then ask what bytes must be sent out, and then allowing them to transition to the next message. * Adding internal locks to protect the sending and receiving state of the `V1Transport` implementation. I believe these aren't strictly needed (opinions welcome) as there is no real way to use `Transport` objects in a multi-threaded fashion without some form of external synchronization (e.g. "get next bytes to send" isn't meaningful to call from multiple threads at the same time without mechanism to control the order they'll actually get sent). Still, I feel it's cleaner to make the object responsible for its own consistency (as we definitely do not want the entire object to be under a single external GUARDED_BY, as that'd prevent simultaneous sending and receiving). * Moving the conversion of messages to bytes on the sending side from `PushMessage` to `SocketSendData`, which is needed to deal with the fact that a transport may not immediately be able to send messages. This PR is not a refactor, though some commits are. Among the semantic changes are: * Changing the send buffer pushback mechanism to trigger based on the memory usage of the buffer rather than the amount of bytes to be sent. This is both closer to the desired behavior, and makes the buffering independent from transport details (which is why it's included here). * When optimistic send is not applicable, the V1 message checksum calculation now runs in the net thread rather than the message handling thread. I believe that's generally an improvement, as the message handling thread is far more computationally bottlenecked already. * The checksum calculation now runs under the `CNode::cs_vSend` lock, which does mean no two checksum calculations for messages sent to the same node can run in parallel, even if running in separate threads. Despite that limitation, having the checksum for non-optimistic sends moved in the net thread is still an improvement, I believe. * Statistics for per-message-type sent bytes are now updated when the bytes are actually handed to the OS rather than in `PushMessage`. This is because the actual serialized sizes aren't known until they've gone through the transport object. A fuzz test of the entire `V1Transport` is included. More elaborate rationale for each of the changes can be found in the commit messages. ACKs for top commit: theStack: re-ACK8a3b6f3387vasild: ACK8a3b6f3387dergoegge: Code review ACK8a3b6f3387Tree-SHA512: 26e9a6df47f1dd3e3f3edb4874edf365728e5a8bbc9d0d4d71fb6000cb2dfde5574902c47ffcf825af6743922f2ff9d31a5a38942a196f4ca6669122e15e42e4
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.