Struct EncryptedMessageV1

pub struct EncryptedMessageV1 {
    pub encrypted: AesGcmPayload,
    pub decryptors_by_curve: IndexMap<CurveType, DecryptorsByCurve>,
}

A PlaintextMessageV1 encrypted with “MultiPartyECIES” for a number of decryptors (public keys).

First, a PlaintextMessageV1 should be created, and encoded as manifest_sbor_encode(plaintext_message) to get the plaintext message payload bytes.

The plaintext message payload bytes are encrypted via (128-bit) AES-GCM with an ephemeral symmetric key.

The (128-bit) AES-GCM symmetric key is encrypted separately for each decryptor public key via (256-bit) AES-KeyWrap. AES-KeyWrap uses a key derived via a KDF (Key Derivation Function) using a shared secret. For each decryptor public key, we create a shared curve point G via static Diffie-Helman between the decryptor public key, and a per-transaction ephemeral public key for that curve type. We then use that shared secret with a key derivation function to create the (256-bit) KEK (Key Encrypting Key): KEK = HKDF(hash: Blake2b, secret: x co-ord of G, salt: [], length: 256 bits).

Note:

• For ECDH, the secret we use is the x coordinate of the shared public point, unhashed. This ECDH output is known as ASN1 X9.63 variant of ECDH. Be careful - libsecp256k1 uses another non-standard variant.
• We persist 128-bit symmetric keys because we wish to save on payload size, and:
  • 128-bit AES is considered secure enough for most use cases (EG bitcoin hash rate is only 2^93 / year)
  • It’s being used with a transient key - so a hypothetical successful attack would only decrypt one message

Fields

encrypted: AesGcmPayload

decryptors_by_curve: IndexMap<CurveType, DecryptorsByCurve>

Trait Implementations

impl Categorize<ManifestCustomValueKind> for EncryptedMessageV1

fn value_kind() -> ValueKind<ManifestCustomValueKind>

impl Clone for EncryptedMessageV1

fn clone(&self) -> EncryptedMessageV1

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EncryptedMessageV1

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

Formats the value using the given formatter.

impl<D> Decode<ManifestCustomValueKind, D> for EncryptedMessageV1

where D: Decoder<ManifestCustomValueKind>,

fn decode_body_with_value_kind( decoder: &mut D, value_kind: ValueKind<ManifestCustomValueKind>, ) -> Result<EncryptedMessageV1, DecodeError>

Decodes the type from the decoder, which should match a preloaded value kind.

impl Describe<ScryptoCustomTypeKind> for EncryptedMessageV1

const TYPE_ID: RustTypeId

The TYPE_ID should give a unique identifier for its SBOR schema type. An SBOR schema type capture details about the SBOR payload, how it should be interpreted, validated and displayed.

fn type_data() -> TypeData<ScryptoCustomTypeKind, RustTypeId>

Returns the local schema for the given type.

fn add_all_dependencies(aggregator: &mut TypeAggregator<ScryptoCustomTypeKind>)

For each type referenced in get_local_type_data, we need to ensure that the type and all of its own references get added to the aggregator.

impl<E> Encode<ManifestCustomValueKind, E> for EncryptedMessageV1

where E: Encoder<ManifestCustomValueKind>,

fn encode_value_kind(&self, encoder: &mut E) -> Result<(), EncodeError>

Encodes the SBOR value’s kind to the encoder

fn encode_body(&self, encoder: &mut E) -> Result<(), EncodeError>

Encodes the SBOR body of the type to the encoder.

impl PartialEq for EncryptedMessageV1

fn eq(&self, other: &EncryptedMessageV1) -> 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 SborTuple<ManifestCustomValueKind> for EncryptedMessageV1

fn get_length(&self) -> usize

impl Eq for EncryptedMessageV1

impl StructuralPartialEq for EncryptedMessageV1