Struct Aes256CbcHmacKey 

pub struct Aes256CbcHmacKey {
    pub(crate) key: Pin<Box<Array<u8, U64>>>,
}

Aes256CbcHmacKey is a symmetric encryption key consisting of two 256-bit keys, one for encryption and one for MAC

Fields

key: Pin<Box<Array<u8, U64>>>

The encryption and MAC keys, stored contiguously as enc_key || mac_key.

They are kept in one buffer rather than two so that the 64-byte composite form — the layout used by the byte serialization, by the Aes256CbcHmacSha256Aead cipher, and by this key’s COSE key view — can be borrowed instead of copied. Use Aes256CbcHmacKey::enc_key and Aes256CbcHmacKey::mac_key for zero-copy views of the individual halves.

Uses a pinned heap data structure, as noted in Pinned heap data

Implementations

impl Aes256CbcHmacKey

pub(crate) fn new(enc_key: &[u8; 32], mac_key: &[u8; 32]) -> Self

Builds a key from its two halves.

pub(crate) fn as_composite_key(&self) -> &[u8; 64]

Returns the 64-byte composite key (enc_key || mac_key), which is the layout expected by the Aes256CbcHmacSha256 and Aes256CbcHmacSha256Aead ciphers.

pub(crate) fn as_slice(&self) -> &[u8]

Returns the composite key as a slice. This is also this key’s legacy byte serialization.

pub(crate) fn enc_key(&self) -> &[u8; 32]

Returns a zero-copy view of the 256-bit encryption key.

pub(crate) fn mac_key(&self) -> &[u8; 32]

Returns a zero-copy view of the 256-bit MAC key.

pub(crate) fn key_id(&self) -> KeyId

Returns the key ID of this key.

Unlike the other COSE key types, this key has no field to store a key ID in — it is serialized as a bare 64-byte blob with no kid. The ID is therefore derived: it is the key’s own RFC 9679 thumbprint truncated to KEY_ID_SIZE bytes. Two keys with identical key material consequently share an ID, and a key’s ID is stable across serialization round-trips.

Trait Implementations

impl Clone for Aes256CbcHmacKey

fn clone(&self) -> Aes256CbcHmacKey

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl ConstantTimeEq for Aes256CbcHmacKey

fn ct_eq(&self, other: &Self) -> Choice

Determine if two items are equal.

fn ct_ne(&self, other: &Self) -> Choice

Determine if two items are NOT equal.

impl Debug for Aes256CbcHmacKey

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

Formats the value using the given formatter.

impl Drop for Aes256CbcHmacKey

fn drop(&mut self)

Executes the destructor for this type.

impl PartialEq for Aes256CbcHmacKey

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.