Expand description

RustCrypto: TLS Codec

MIT licensed Project Chat Rust Version


This crate implements the TLS codec as defined in RFC 8446 as well as some extensions required by MLS.

With the derive feature TlsSerialize and TlsDeserialize can be derived.

The crate also provides the following data structures that implement TLS serialization/deserialization

  • u8, u16, u32, u64
  • TlsVecU8, TlsVecU16, TlsVecU32
  • SecretTlsVecU8, SecretTlsVecU16, SecretTlsVecU32 The same as the TlsVec* versions but it implements zeroize, requiring the elements to implement zeroize as well.
  • TlsSliceU8, TlsSliceU16, TlsSliceU32 are lightweight wrapper for slices that allow to serialize them without having to create a TlsVec*.
  • TlsByteSliceU8, TlsByteSliceU16, TlsByteSliceU32, and TlsByteVecU8, TlsByteVecU16, TlsByteVecU32 are provided with optimized implementations for byte vectors.
  • [u8; l], for l ∈ [1..128]
  • Serialize for Option<T> where T: Serialize
  • Deserialize for Option<T> where T: Deserialize
  • Serialize for (T, U) and (T, U, V) where T, U, V implement Serialize`
  • Deserialize for (T, U) and (T, U, V) where T, U, V implement Deserialize`

Minimum Supported Rust Version

This crate requires Rust 1.56 at a minimum.

We may change the MSRV in the future, but it will be accompanied by a minor version bump.


Licensed under either of:

at your option.


Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.


use tls_codec::{TlsVecU8, Serialize, Deserialize};
let mut b = &[1u8, 4, 77, 88, 1, 99] as &[u8];

let a = u8::tls_deserialize(&mut b).expect("Unable to tls_deserialize");
assert_eq!(1, a);
println!("b: {:?}", b);
let v = TlsVecU8::<u8>::tls_deserialize(&mut b).expect("Unable to tls_deserialize");
assert_eq!(&[77, 88, 1, 99], v.as_slice());



Errors that are thrown by this crate.


The Deserialize trait defines functions to deserialize a byte slice to a struct or enum.

The Serialize trait provides functions to serialize a struct or enum.

The Size trait needs to be implemented by any struct that should be efficiently serialized. This allows to collect the length of a serialized structure before allocating memory.

Derive Macros