The Miscreant project has been abandoned and archived.
The Rust implementation has been adapted into the new aes-siv crate which
implements both the AES-CMAC-SIV and AES-PMAC-SIV constructions:
https://github.com/RustCrypto/AEADs/tree/master/aes-siv
Please migrate to the aes-siv crate.
Alternatively see the aes-gcm-siv crate for a newer, faster construction
which provides similar properties: