Struct EchGreaseShape 

pub struct EchGreaseShape { /* private fields */ }

Available on crate features boring and crypto and std only.

The algorithms and lengths of an ECH GREASE extension, never its keys or bytes.

Apply with super::ClientHelloShape::with_ech_grease. GREASE must also be enabled with super::SslRef::set_enable_ech_grease, and TLS 1.3 must be offered. A usable real ECH configuration takes precedence; this shape only applies when BoringSSL falls back to GREASE. An unusable configuration still follows the native ECH rejection policy.

Each new handshake generates fresh X25519 encapsulation, random payload and config ID, independently of super::GreaseValues. A HelloRetryRequest reuses the first GREASE extension byte for byte. A new connection, including one made with real ECH retry configs, must be configured separately.

Implementations

impl EchGreaseShape

pub const ENCAPSULATED_KEY_LEN: usize = 32

The X25519 encapsulated key length. Other KEMs are not supported here.

pub const MIN_PAYLOAD_LEN: usize = 16

Minimum payload length, including the AEAD’s 16-byte tag.

pub const MAX_PAYLOAD_LEN: usize = 65_489

Largest payload that fits the TLS extensions block with ECH framing. The complete ClientHello must also fit its length prefixes: other extensions reduce the available space. If it does not fit, the handshake fails before writing a ClientHello.

pub fn new( cipher_suite: EchGreaseCipherSuite, payload_len: usize, ) -> Result<EchGreaseShape, ErrorStack>

Selects an exact payload length in bytes, including the AEAD tag. Lengths need not be multiples of 32.

pub fn from_wire( kdf_id: u16, aead_id: u16, encapsulated_key_len: usize, payload_len: usize, ) -> Result<EchGreaseShape, ErrorStack>

Validates algorithms and lengths retained from a captured extension. Accepts KDF 1, AEAD 1/2/3, and exactly 32 encapsulation bytes. No captured cryptographic bytes or config ID are accepted.

pub const fn cipher_suite(self) -> EchGreaseCipherSuite

The selected HPKE cipher suite.

pub const fn payload_len(self) -> usize

The exact wire payload length, including the AEAD tag.

Trait Implementations

impl Clone for EchGreaseShape

fn clone(&self) -> EchGreaseShape

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for EchGreaseShape

impl Debug for EchGreaseShape

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Eq for EchGreaseShape

impl Hash for EchGreaseShape

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for EchGreaseShape

fn eq(&self, other: &EchGreaseShape) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for EchGreaseShape