Struct KariRecipient 

pub struct KariRecipient {
    pub issuer_der: Vec<u8>,
    pub serial: Vec<u8>,
    pub curve: KariCurve,
    pub kdf: KariKdf,
    pub recipient_pub_bytes: Vec<u8>,
    pub ephemeral_scalar: Vec<u8>,
}

One KARI recipient slot the writer will emit. The recipient is identified by their X.509 certificate (issuer + serial — KARI RecipientEncryptedKey IAS form), and recipient_pub_bytes carries their public key in the curve’s encoded form (SEC1 uncompressed for P-256 / P-384 / P-521, raw 32-byte u-coordinate for X25519).

Fields

issuer_der: Vec<u8>

Recipient certificate’s issuer DER (a SEQUENCE — same shape as super::cms_build::RecipientIdRef::IssuerAndSerial::issuer_der).

serial: Vec<u8>

Recipient cert’s serial number INTEGER body bytes.

curve: KariCurve

Curve the recipient’s keypair lives on. Determines the ECDH primitive + ephemeral keypair shape the writer will emit.

kdf: KariKdf

KDF binding the writer will encode in KeyAgreeRecipientInfo.keyEncryptionAlgorithm. Defaults via the per-curve constructors to super::kari::KariCurve::default_kdf: RFC 5753 §7.1.4 X9.63 with the matching hash for NIST curves; RFC 8418 §2.1 X9.63-SHA-256 for X25519. Use the x25519_hkdf_* constructors to switch X25519 to the modern RFC 8418 §2.2 HKDF binding.

recipient_pub_bytes: Vec<u8>

Recipient’s encoded public key. SEC1 uncompressed point for NIST curves; raw 32-byte u-coordinate for X25519.

ephemeral_scalar: Vec<u8>

Ephemeral private scalar used for THIS recipient’s wrap. Each recipient gets its own ephemeral keypair so the writer can mix curves across recipients in a single envelope (one KARI per curve / ephemeral). Tests pin to a deterministic value; production callers should use a fresh random scalar per recipient.

Implementations

impl KariRecipient

pub fn p256( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_sec1: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Build a P-256 recipient (X9.63-SHA-256 KDF per RFC 5753 §7.1.4).

pub fn p384( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_sec1: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Build a P-384 recipient (X9.63-SHA-384 KDF per RFC 5753 §7.1.4).

pub fn p521( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_sec1: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-16: build a P-521 recipient (X9.63-SHA-512 KDF per RFC 5753 §7.1.4 — dhSinglePass-stdDH-sha512kdf-scheme, OID 1.3.132.1.11.3).

pub fn x25519( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x25519: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Build an X25519 recipient with the legacy X9.63-SHA-256 KDF binding (RFC 8418 §2.1).

pub fn x25519_hkdf_sha256( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x25519: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-16: build an X25519 recipient with the modern HKDF-SHA-256 KDF binding (RFC 8418 §2.2 — dhSinglePass-stdDH-hkdf-sha256-scheme, smime-alg 19).

pub fn x25519_hkdf_sha384( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x25519: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-16: build an X25519 recipient with HKDF-SHA-384 (RFC 8418 §2.2 — dhSinglePass-stdDH-hkdf-sha384-scheme, smime-alg 20).

pub fn x25519_hkdf_sha512( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x25519: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-16: build an X25519 recipient with HKDF-SHA-512 (RFC 8418 §2.2 — dhSinglePass-stdDH-hkdf-sha512-scheme, smime-alg 21).

pub fn x448( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x448: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-24: build an X448 recipient with the default X9.63-SHA-512 KDF binding (RFC 8418 §2.1 — dhSinglePass-stdDH-sha512kdf-scheme). recipient_pub_x448 is the recipient’s 56-byte raw u-coordinate; ephemeral_scalar is the 56-byte ephemeral private key (RFC 7748 §5 clamping is applied by the underlying x448 crate at scalar load).

pub fn x448_hkdf_sha256( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x448: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-24: build an X448 recipient with the modern HKDF-SHA-256 KDF binding (RFC 8418 §2.2 — dhSinglePass-stdDH-hkdf-sha256-scheme, smime-alg 19). Same shape as Self::x448 but with the HKDF flavour swapped in.

pub fn x448_hkdf_sha384( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x448: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-24: build an X448 recipient with HKDF-SHA-384 (RFC 8418 §2.2 — dhSinglePass-stdDH-hkdf-sha384-scheme, smime-alg 20).

pub fn x448_hkdf_sha512( issuer_der: Vec<u8>, serial: Vec<u8>, recipient_pub_x448: Vec<u8>, ephemeral_scalar: Vec<u8>, ) -> Self

Round-24: build an X448 recipient with HKDF-SHA-512 (RFC 8418 §2.2 — dhSinglePass-stdDH-hkdf-sha512-scheme, smime-alg 21 — the security-strength match for X448’s 224-bit level under HKDF).

Trait Implementations

impl Clone for KariRecipient

fn clone(&self) -> KariRecipient

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for KariRecipient

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

Formats the value using the given formatter.