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0.1.0 (current) Rating: Positive Thoroughness: Low Understanding: Medium

Approved without comment by kpcyrd on 2021-11-19


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does-not-implement-crypto (implies crypto-safe)

Inspection reveals that the crate in question does not attempt to implement any cryptographic algorithms on its own.

Note that certification of this does not require an expert on all forms of cryptography: it's expected for crates we import to be "good enough" citizens, so they'll at least be forthcoming if they try to implement something cryptographic. When in doubt, please ask an expert.

crypto-safe
Implied by other criteria

All crypto algorithms in this crate have been reviewed by a relevant expert.

Note: If a crate does not implement crypto, use does-not-implement-crypto, which implies crypto-safe, but does not require expert review in order to audit for.

rule-of-two-safe-to-deploy (implies safe-to-deploy)

This is a stronger requirement than the built-in safe-to-deploy criteria, motivated by Chromium's rule-of-two related requirements: https://chromium.googlesource.com/chromium/src/+/master/docs/security/rule-of-2.md#unsafe-code-in-safe-languages

This crate will not introduce a serious security vulnerability to production software exposed to untrusted input.

Auditors are not required to perform a full logic review of the entire crate. Rather, they must review enough to fully reason about the behavior of all unsafe blocks and usage of powerful imports. For any reasonable usage of the crate in real-world software, an attacker must not be able to manipulate the runtime behavior of these sections in an exploitable or surprising way.

Ideally, ambient capabilities (e.g. filesystem access) are hardened against manipulation and consistent with the advertised behavior of the crate. However, some discretion is permitted. In such cases, the nature of the discretion should be recorded in the notes field of the audit record.

Any unsafe code in this crate must, in general, be kept well-contained, and documentation must exist to describe how Rust's invariants are being upheld despite the unsafe block(s). Nontrivial uses of unsafe must be reviewed by an expert in Rust's unsafety guarantees/non-guarantees.

For crates which generate deployed code (e.g. build dependencies or procedural macros), reasonable usage of the crate should output code which meets the above criteria.

safe-to-deploy (implies safe-to-run)
Implied by other criteria

This crate will not introduce a serious security vulnerability to production software exposed to untrusted input. More…

safe-to-run
Implied by other criteria

This crate can be compiled, run, and tested on a local workstation or in controlled automation without surprising consequences. More…

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