p2p: cherry-pick commits from geth for peering issues #1267
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Node discovery periodically revalidates the nodes in its table by sending PING, checking if they are still alive. I recently noticed some issues with the implementation of this process, which can cause strange results such as nodes dropping unexpectedly, certain nodes not getting revalidated often enough, and bad results being returned to incoming FINDNODE queries. In this change, the revalidation process is improved with the following logic: - We maintain two 'revalidation lists' containing the table nodes, named 'fast' and 'slow'. - The process chooses random nodes from each list on a randomized interval, the interval being faster for the 'fast' list, and performs revalidation for the chosen node. - Whenever a node is newly inserted into the table, it goes into the 'fast' list. Once validation passes, it transfers to the 'slow' list. If a request fails, or the node changes endpoint, it transfers back into 'fast'. - livenessChecks is incremented by one for successful checks. Unlike the old implementation, we will not drop the node on the first failing check. We instead quickly decay the livenessChecks give it another chance. - Order of nodes in bucket doesn't matter anymore. I am also adding a debug API endpoint to dump the node table content. Co-authored-by: Martin HS <[email protected]>
In #29572, I assumed the revalidation list that the node is contained in could only ever be changed by the outcome of a revalidation request. But turns out that's not true: if the node gets removed due to FINDNODE failure, it will also be removed from the list it is in. This causes a crash. The invariant is: while node is in table, it is always in exactly one of the two lists. So it seems best to store a pointer to the current list within the node itself.
enode.Node has separate accessor functions for getting the IP, UDP port and TCP port. These methods performed separate checks for attributes set in the ENR. With this PR, the accessor methods will now return cached information, and the endpoint is determined when the node is created. The logic to determine the preferred endpoint is now more correct, and considers how 'global' each address is when both IPv4 and IPv6 addresses are present in the ENR.
It seems the semantic differences between addFoundNode and addInboundNode were lost in (and are unsure if is available) whereas addInboundNode is for adding nodes that have contacted the local node and we can verify they are active. handleAddNode seems to be the consolidation of those two methods, yet it bumps the node in the bucket (updating it's IP addr) even if the node was not an inbound. This PR fixes this. It wasn't originally caught in tests like TestTable_addSeenNode because the manipulation of the node object actually modified the node value used by the test. New logic is added to reject non-inbound updates unless the sequence number of the (signed) ENR increases. Inbound updates, which are published by the updated node itself, are always accepted. If an inbound update changes the endpoint, the node will be revalidated on an expedited schedule. Co-authored-by: Felix Lange <[email protected]>
Here we clean up internal uses of type discover.node, converting most code to use enode.Node instead. The discover.node type used to be the canonical representation of network hosts before ENR was introduced. Most code worked with *node to avoid conversions when interacting with Table methods. Since *node also contains internal state of Table and is a mutable type, using *node outside of Table code is prone to data races. It's also cleaner not having to wrap/unwrap *enode.Node all the time. discover.node has been renamed to tableNode to clarify its purpose. While here, we also change most uses of net.UDPAddr into netip.AddrPort. While this is technically a separate refactoring from the *node -> *enode.Node change, it is more convenient because *enode.Node handles IP addresses as netip.Addr. The switch to package netip in discovery would've happened very soon anyway. The change to netip.AddrPort stops at certain interface points. For example, since package p2p/netutil has not been converted to use netip.Addr yet, we still have to convert to net.IP/net.UDPAddr in a few places.
Co-authored-by: Stefan <[email protected]>
pratikspatil024
added
the
do not squash and merge
cffls
approved these changes
Jun 13, 2024
manav2401
approved these changes
Jun 13, 2024
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Description
cherry-pickd the following PRs from geth for peering issues
ethereum/go-ethereum#29572
ethereum/go-ethereum#29864
ethereum/go-ethereum#29801
ethereum/go-ethereum#29827
ethereum/go-ethereum#29836
ethereum/go-ethereum#29844
ethereum/go-ethereum#29235
Changes
Breaking changes
Please complete this section if any breaking changes have been made, otherwise delete it
Nodes audience
In case this PR includes changes that must be applied only to a subset of nodes, please specify how you handled it (e.g. by adding a flag with a default value...)
Checklist
Cross repository changes
Testing
Manual tests
Please complete this section with the steps you performed if you ran manual tests for this functionality, otherwise delete it
Additional comments
Please post additional comments in this section if you have them, otherwise delete it