Enum CryptoType 

#[non_exhaustive]
pub enum CryptoType {
    ElGamal,
    EciesP256,
    EciesX25519,
    EciesMlkem512X25519,
    EciesMlkem768X25519,
    EciesMlkem1024X25519,
}

An encryption algorithm a destination’s LeaseSet2 can advertise as usable – see I2pRouter::create_persistent_destination’s encryption_types parameter.

Values are libi2pd’s protocol-level CryptoKeyType (libi2pd/Identity.h). This covers only the advertised encryption capability, never the identity certificate, which is ElGamal either way (see I2pRouter::generate_keys).

An empty encryption_types slice already gets libi2pd’s hybrid default (ElGamal + ECIES-X25519, plus ML-KEM-768 on a post-quantum-capable backend); explicit values only ever narrow that. The EciesMlkem* variants are new enough that older peers may not understand a destination advertising one, so they trade reachability for long-term confidentiality.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

ElGamal

The original ElGamal scheme. For old persisted keys only.

EciesP256

ECIES on the P-256 curve with AES-256-CBC. Not widely used on the I2P network.

EciesX25519

ECIES-X25519-AEAD (ChaCha20/Poly1305). The I2P network’s current default.

EciesMlkem512X25519

ECIES-X25519-AEAD hybridized with ML-KEM-512 (NIST PQC category 1).

EciesMlkem768X25519

ECIES-X25519-AEAD hybridized with ML-KEM-768 (NIST PQC category 3).

EciesMlkem1024X25519

ECIES-X25519-AEAD hybridized with ML-KEM-1024 (NIST PQC category 5).

Implementations

impl CryptoType

pub fn is_supported(self) -> bool

Whether the linked crypto backend can actually perform this algorithm. Always true for the classical types; for the EciesMlkem* ones it runs a real generate/encapsulate/decapsulate round trip through libi2pd’s MLKEMKeys rather than checking a feature flag. Sub-millisecond but not free – cache it, don’t call it per connection. Needs no running router.

Check this before naming an EciesMlkem* type in create_persistent_destination: a LeaseSet2 advertising only algorithms this router cannot perform leaves the destination unreachable, with nothing in the address or the creation result to say so.

Trait Implementations

impl Clone for CryptoType

fn clone(&self) -> CryptoType

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for CryptoType

impl Debug for CryptoType

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

Formats the value using the given formatter.

impl Default for CryptoType

fn default() -> CryptoType

Returns the “default value” for a type.

impl Eq for CryptoType

impl PartialEq for CryptoType

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for CryptoType