During snap-sync, we request ranges of values: either a range of accounts or a range of storage values. For any large trie, e.g. the main account trie or a large storage trie, we cannot fetch everything at once.
Short version; we split it up and request in multiple stages. To do so, we use an origin field, to say "Give me all storage key/values where key > 0x20000000000000000". When the server fulfils this, the server provides the first key after origin, let's say 0x2e030000000000000 -- never providing the exact origin. However, the client-side needs to be able to verify that the 0x2e03.. indeed is the first one after 0x2000.., and therefore the attached proof concerns the origin, not the first key.
So, short-short version: the left-hand side of the proof relates to the origin, and is free-standing from the first leaf.
On the other hand, (pun intended), the right-hand side, there's no such 'gap' between "along what path does the proof walk" and the last provided leaf. The proof must prove the last element (unless there are no elements).
Therefore, we can simplify the semantics for trie.VerifyRangeProof by removing an argument. This doesn't make much difference in practice, but makes it so that we can remove some tests. The reason I am raising this is that the upcoming stacktrie-based verifier does not support such fancy features as standalone right-hand borders.
This change addresses an issue in snap sync, specifically when the entire sync process can be halted due to an encountered empty storage range.
Currently, on the snap sync client side, the response to an empty (partial) storage range is discarded as a non-delivery. However, this response can be a valid response, when the particular range requested does not contain any slots.
For instance, consider a large contract where the entire key space is divided into 16 chunks, and there are no available slots in the last chunk [0xf] -> [end]. When the node receives a request for this particular range, the response includes:
The proof with origin [0xf]
A nil storage slot set
If we simply discard this response, the finalization of the last range will be skipped, halting the entire sync process indefinitely. The test case TestSyncWithUnevenStorage can reproduce the scenario described above.
In addition, this change also defines the common variables MaxAddress and MaxHash.
This is a minor refactor in preparation of changes to range verifier. This PR contains no intentional functional changes but moves (and renames) the light.NodeSet
The EmptyRootHash and EmptyCodeHash are defined everywhere in the codebase, this PR replaces all of them with unified one defined in core/types package, and also defines constants for TxRoot, WithdrawalsRoot and UncleRoot
This PR makes it so that the snap server responds to trie heal requests when possible, even if the snapshot does not exist. The idea being that it might prolong the lifetime of a state root, so we don't have to pivot quite as often.
This enables the following linters
- typecheck
- unused
- staticcheck
- bidichk
- durationcheck
- exportloopref
- gosec
WIth a few exceptions.
- We use a deprecated protobuf in trezor. I didn't want to mess with that, since I cannot meaningfully test any changes there.
- The deprecated TypeMux is used in a few places still, so the warning for it is silenced for now.
- Using string type in context.WithValue is apparently wrong, one should use a custom type, to prevent collisions between different places in the hierarchy of callers. That should be fixed at some point, but may require some attention.
- The warnings for using weak random generator are squashed, since we use a lot of random without need for cryptographic guarantees.
This PR groups all built-in network flags together and list them in the command as a whole.
And all database path flags(datadir, ancient) are also grouped, since usually these two are
used together.
