Consensys / gnark

gnark is a fast zk-SNARK library that offers a high-level API to design circuits. The library is open source and developed under the Apache 2.0 license

https://hackmd.io/@gnark

Apache License 2.0

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fix: expmod precompile if modulus is 1 #1294

Closed ivokub closed 1 month ago

ivokub commented 1 month ago

Description

Even though EVM yellow paper defines 0^0=1, then this holds only if modulus is not 0 or 1. In either such case any exponentiation is 0.

Fixes LA audit Issue G

Type of change

[x] Bug fix (non-breaking change which fixes an issue)

How has this been tested?

[x] TestEdgeCases - changed the edge case test

How has this been benchmarked?

Not benchmarked

Checklist:

[x] I have performed a self-review of my code
[x] I have commented my code, particularly in hard-to-understand areas
[x] I have made corresponding changes to the documentation
[x] I have added tests that prove my fix is effective or that my feature works
[x] I did not modify files generated from templates
[x] golangci-lint does not output errors locally
[x] New and existing unit tests pass locally with my changes
[x] Any dependent changes have been merged and published in downstream modules