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.
* cmd, core: resolve scheme from a read-write database
* cmd, core, eth: move the scheme check in the ethereum constructor
* cmd/geth: dump should in ro mode
* cmd: reverts
This change
- Removes the owner-notion from a stacktrie; the owner is only ever needed for comitting to the database, but the commit-function, the `writeFn` is provided by the caller, so the caller can just set the owner into the `writeFn` instead of having it passed through the stacktrie.
- Removes the `encoding.BinaryMarshaler`/`encoding.BinaryUnmarshaler` interface from stacktrie. We're not using it, and it is doubtful whether anyone downstream is either.
Adding a space beween function opOrigin() and opcCaller() in instruciton.go.
Adding a space beween function opkeccak256() and opAddress() in instruciton.go.
When MatcherSession encounters an error, it attempts to close the session.
Closing waits for all goroutines to finish, including the 'distributor'. However, the
distributor will not exit until all requests have returned.
This patch fixes the issue by delivering the (empty) result to the distributor
before calling Close().
* cmd/evm: improve flags handling
This fixes some issues with flags in cmd/evm. The supported flags did not
actually show up in help output because they weren't categorized. I'm also
adding the VM-related flags to the run command here so they can be given
after the subcommand name. So it can be run like this now:
./evm run --code 6001 --debug
* cmd/evm: enable all forks by default in run command
The default genesis was just empty with no forks at all, which is annoying because
contracts will be relying on opcodes introduced in a fork. So this changes the default to
have all forks enabled.
* core/asm: fix some issues in the assembler
This fixes minor bugs in the old assembler:
- It is now possible to have comments on the same line as an instruction.
- Errors for invalid numbers in the jump instruction are reported better
- Line numbers in errors were off by one
