https://hackerone.com/reports/991106
> It’s possible to use UDP gossip protocol to amplify DDoS attacks. An attacker
> can spoof IP address in UDP packet when sending PullRequest to the node.
> There's no any validation if provided source IP address is not spoofed and
> the node can send much larger PullResponse to victim's IP. As I checked,
> PullRequest is about 290 bytes, while PullResponse is about 10 kB. It means
> that amplification is about 34x. This way an attacker can easily perform DDoS
> attack both on Solana node and third-party server.
>
> To prevent it, need for example to implement ping-pong mechanism similar as
> in Ethereum: Before accepting requests from remote client needs to validate
> his IP. Local node sends Ping packet to the remote node and it needs to reply
> with Pong packet that contains hash of matching Ping packet. Content of Ping
> packet is unpredictable. If hash from Pong packet matches, local node can
> remember IP where Ping packet was sent as correct and allow further
> communication.
>
> More info:
> https://github.com/ethereum/devp2p/blob/master/discv4.md#endpoint-proof
> https://github.com/ethereum/devp2p/blob/master/discv4.md#wire-protocol
The commit adds a PingCache, which maintains records of remote nodes
which have returned a valid response to a ping message, and on-the-fly
ping messages pending a pong response from the remote node.
When handling pull-requests, those from addresses which have not passed
the ping-pong check are filtered out, and additionally ping packets are
added for addresses which need to be (re)verified.
crds_gossip tests start large networks, which with large thread-pools
will exhaust system resources, causing failures in ci tests:
https://buildkite.com/solana-labs/solana/builds/31953
The commit limits size of thread-pools in the test.
Based on run-time profiles, the majority time of new_pull_requests is
spent building bloom filters, in hashing and bit-vec ops.
This commit builds crds filters in parallel using rayon constructs. The
added benchmark shows ~5x speedup (4-core machine, 8 threads).
* Batch process pull responses
* Generate pull requests at 1/2 rate
* Do filtering work of process_pull_response in read lock
Only take write lock to insert if needed.
* filter messages that are likely to be pushed from the response
* tests
* tests
* wait to start filtering responses, and push stats to influx
* wait to start filtering responses, and push stats to influx
* reduce the timers to match the publish self timeout
* fmt
* fmt
* Add CrdsValue timeout checks on Pull Responses
* Allow older values to enter Crds as long as a ContactInfo exists
* Allow staked contact infos to be inserted into crds if they haven't expired
* Try and handle oveflows
* Fix test
* Some comments
* Fix compile
* fix test deadlock
* Add a test for processing timed out values received via pull response
* Remove Blobs and switch to Packets
* Fix some gossip messages not respecting MTU size
* Failure to serialize is not fatal
* Add log macros
* Remove unused extern
* Apparently macro use is required
* Explicitly scope macro
* Fix test compile
* Coalesce gossip pull requests and serve them in batches
* batch all filters and immediately respond to messages in gossip
* Fix tests
* make download_from_replicator perform a greedy recv
* fixed bloom filter math
* Add split each pull request into multiple pulls with different filters
* Rework CrdsFilter to generate all possible masks to cover the keyspace
* Limit the bloom sizes such that each pull request is no larger than mtu
* Be able to create bank snapshots
* fix clippy
* load snapshot on start
* regenerate account index from the storage
* Remove rc feature dependency
* cleanup
* save snapshot for slot 0
* Add Epoch Slots to gossip
* Add new gossip structure to support Repair
* remove unnecessary clones
* Setup dummy fast repair in repair_service
* PR comments
* move core tests to core
* remove window
* fix up flaky tests
* test_entryfication needs a singly-threaded banking_stage
* move core benches to core
* remove unnecessary dependencies
* remove core as a member for now, test it like runtime
* stop running tests twice
* remove duplicate runs of tests in perf
behzad nouri
Michael Vines
sakridge
anatoly yakovenko
Kristofer Peterson
Sagar Dhawan
Pankaj Garg
Justin Starry
Sathish
Rob Walker
carllin
Greg Fitzgerald
