Check block_timestamp always increases. #638
Merged
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
github-actions
bot
added
the
crate: evm_arithmetization
Nashtare
reviewed
Sep 18, 2024
| // In other words, we range-check `diff = timestamp - prev_timestamp - 1` | ||
| // between 0 and 2ˆ32. | ||
| let diff = builder.sub(timestamp, prev_timestamp); | ||
| let diff = builder.add_const(diff, F::NEG_ONE); |
There was a problem hiding this comment.
I don't think we should do a minus 1 here. Timestamp is UNIX based, in seconds if I'm correct. If a chain were to have a block time of < 1 sec this check would fail. We should probably allow for 0 diff.
Nashtare
approved these changes
Sep 18, 2024
muursh
reviewed
Sep 19, 2024
| ) { | ||
| // We check that timestamp >= prev_timestamp. | ||
| // In other words, we range-check `diff = timestamp - prev_timestamp` | ||
| // between 0 and 2ˆ32. |
There was a problem hiding this comment.
Suggested change
| // between 0 and 2ˆ32. | |
| // is between 0 and 2ˆ32. |
muursh
approved these changes
Sep 19, 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Outdated suggestions cannot be applied.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.
This PR aims at addressing #634.
In
create_block_circuit, it range-checksdiff = timestamp - parent_timestamp - 1between0and2ˆ32, as a way to ensuretimestamp > parent_timestamp.