crytic/caracalStatic Analyzer for Starknet smart contracts
Caracal is a static analyzer tool over the SIERRA representation for Starknet smart contracts.
Precompiled binaries are available on our releases page. If you are using Cairo compiler 1.x.x uses the binary v0.1.x otherwise if you are using the Cairo compiler 2.x.x uses v0.2.x.
You need the Rust compiler and Cargo. Building from git:
cargo install --git https://github.com/crytic/caracal --profile release --force
Building from a local copy:
git clone https://github.com/crytic/caracal
cd caracal
cargo install --path . --profile release --force
List detectors:
caracal detectors
List printers:
caracal printers
To use with a standalone cairo file and you have a local cairo compiler binary it's enough to point it to the file. Otherwise otherwise a bundled compiler is used and you need to pass the path to the corelib library either with the --corelib cli option or by setting the CORELIB_PATH environment variable.
Run detectors:
caracal detect path/file/to/analyze
caracal detect path/file/to/analyze --corelib path/to/corelib/src
Run printers:
caracal print path/file/to/analyze --printer printer_to_use --corelib path/to/corelib/src
If you have a cairo project with multiple files and contracts you may need to specify which contracts with --contract-path. The local cairo compiler binary is used if available otherwise a bundled compiler is used. In the latter case you also need to specify the corelib as explained above for the standalone case. The path is the directory where cairo_project.toml resides.
Run detectors:
caracal detect path/to/dir
caracal detect path/to/dir --contract-path token::myerc20::... token::myerc721::...
Run printers:
caracal print path/to/dir --printer printer_to_use
If you have a project that uses Scarb you need to add the following in Scarb.toml:
[[target.starknet-contract]]
sierra = true
[cairo]
sierra-replace-ids = true
Then pass the path to the directory where Scarb.toml resides. Run detectors:
caracal detect path/to/dir
Run printers:
caracal print path/to/dir --printer printer_to_use
The Cairo column represent the compiler version(s) for which the detector is valid.
cfg: Export the CFG of each function to a .dot filecallgraph: Export function call graph to a .dot fileCheck the wiki on the following topics:
| Num | Detector | What it Detects | Impact | Confidence | Cairo |
|---|
| 1 | controlled-library-call | Library calls with a user controlled class hash | High | Medium | 1 & 2 |
| 2 | unchecked-l1-handler-from | Detect L1 handlers without from address check | High | Medium | 1 & 2 |
| 3 | felt252-unsafe-arithmetic | Detect user controlled operations with felt252 type, which is not overflow/underflow safe | Medium | Medium | 1 & 2 |
| 4 | reentrancy | Detect when a storage variable is read before an external call and written after | Medium | Medium | 1 & 2 |
| 5 | read-only-reentrancy | Detect when a view function read a storage variable written after an external call | Medium | Medium | 1 & 2 |
| 6 | unused-events | Events defined but not emitted | Medium | Medium | 1 & 2 |
| 7 | unused-return | Unused return values | Medium | Medium | 1 & 2 |
| 8 | unenforced-view | Function has view decorator but modifies state | Medium | Medium | 1 |
| 9 | tx-origin | Detect usage of the transaction origin address as access control | Medium | Medium | 2 |
| 10 | unused-arguments | Unused arguments | Low | Medium | 1 & 2 |
| 11 | reentrancy-benign | Detect when a storage variable is written after an external call but not read before | Low | Medium | 1 & 2 |
| 12 | reentrancy-events | Detect when an event is emitted after an external call leading to out-of-order events | Low | Medium | 1 & 2 |
| 13 | dead-code | Private functions never used | Low | Medium | 1 & 2 |
| 14 | use-after-pop-front | Detect use of an array or a span after removing element(s) | Low | Medium | 1 & 2 |