Struct EncryptedMessage

pub struct EncryptedMessage { /* private fields */ }

A secure encrypted message using IETF ChaCha20-Poly1305 authenticated encryption.

EncryptedMessage represents data that has been encrypted using a symmetric key with the ChaCha20-Poly1305 AEAD (Authenticated Encryption with Associated Data) construction as specified in RFC-8439.

An EncryptedMessage contains:

• ciphertext: The encrypted data (same length as the original plaintext)
• aad: Additional Authenticated Data that is not encrypted but is authenticated (optional)
• nonce: A 12-byte number used once for this specific encryption operation
• auth: A 16-byte authentication tag that verifies the integrity of the message

The aad field is often used to include the Digest of the plaintext, which allows verification of the plaintext after decryption and preserves the unique identity of the data when used with structures like Gordian Envelope.

To facilitate decoding, it is recommended that the plaintext of an EncryptedMessage be tagged CBOR.

CDDL:

EncryptedMessage =
    #6.40002([ ciphertext: bstr, nonce: bstr, auth: bstr, ? aad: bstr ]) ; TAG_ENCRYPTED

Implementations

impl EncryptedMessage

pub fn new( ciphertext: impl Into<Vec<u8>>, aad: impl Into<Vec<u8>>, nonce: Nonce, auth: AuthenticationTag, ) -> Self

Restores an EncryptedMessage from its CBOR representation.

This is a low-level function that is not normally needed.

pub fn ciphertext(&self) -> &Vec<u8>

Returns a reference to the ciphertext data.

pub fn aad(&self) -> &Vec<u8>

Returns a reference to the additional authenticated data (AAD).

pub fn nonce(&self) -> &Nonce

Returns a reference to the nonce value used for encryption.

pub fn authentication_tag(&self) -> &AuthenticationTag

Returns a reference to the authentication tag value used for encryption.

pub fn opt_digest(&self) -> Option<Digest>

Returns an optional Digest instance if the AAD data can be parsed as CBOR.

pub fn has_digest(&self) -> bool

Returns true if the AAD data can be parsed as CBOR.

Trait Implementations

impl AsRef<EncryptedMessage> for EncryptedMessage

Implements AsRef<EncryptedMessage> to allow self-reference.

fn as_ref(&self) -> &EncryptedMessage

Converts this type into a shared reference of the (usually inferred) input type.

impl CBORTagged for EncryptedMessage

Implements CBORTagged to provide the CBOR tag for the EncryptedMessage.

fn cbor_tags() -> Vec<Tag>

Returns the CBOR tags associated with this type.

impl CBORTaggedDecodable for EncryptedMessage

Implements CBORTaggedDecodable to provide CBOR decoding functionality.

fn from_untagged_cbor(cbor: CBOR) -> Result<Self>

Creates an instance of this type by decoding it from untagged CBOR.

fn from_tagged_cbor(cbor: CBOR) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from tagged CBOR.

fn from_tagged_cbor_data(data: impl AsRef<[u8]>) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from binary encoded tagged CBOR.

fn from_untagged_cbor_data(data: impl AsRef<[u8]>) -> Result<Self, Error>

where Self: Sized,

Creates an instance of this type by decoding it from binary encoded untagged CBOR.

impl CBORTaggedEncodable for EncryptedMessage

Implements CBORTaggedEncodable to provide CBOR encoding functionality.

fn untagged_cbor(&self) -> CBOR

Returns the untagged CBOR encoding of this instance.

fn tagged_cbor(&self) -> CBOR

Returns the tagged CBOR encoding of this instance.

fn tagged_cbor_data(&self) -> Vec<u8>

Returns the tagged value in CBOR binary representation.

impl Clone for EncryptedMessage

fn clone(&self) -> EncryptedMessage

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for EncryptedMessage

Implements Debug formatting to display the message contents in a structured format.

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

Formats the value using the given formatter.

impl DigestProvider for EncryptedMessage

Implements DigestProvider to provide the digest stored in the AAD field.

fn digest(&self) -> Cow<'_, Digest>

Returns a digest that uniquely characterizes the content of the implementing type.

impl From<EncryptedMessage> for CBOR

Implements conversion from EncryptedMessage to CBOR for serialization.

fn from(value: EncryptedMessage) -> Self

Converts to this type from the input type.

impl PartialEq for EncryptedMessage

fn eq(&self, other: &EncryptedMessage) -> 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.

impl TryFrom<CBOR> for EncryptedMessage

Implements TryFrom<CBOR> for EncryptedMessage to support conversion from CBOR data.

type Error = Error

The type returned in the event of a conversion error.

fn try_from(cbor: CBOR) -> Result<Self>

Performs the conversion.

impl Eq for EncryptedMessage

impl StructuralPartialEq for EncryptedMessage