Struct Credential 

pub struct Credential {
    pub id: Vec<u8>,
    pub public_key: PublicKey,
    pub sign_count: u32,
    pub user_id: Vec<u8>,
    pub rp_id: String,
    pub created_at: SystemTime,
    pub backup_eligible: bool,
    pub backup_state: bool,
}

A registered credential persisted on the relying-party side after a successful registration ceremony.

The caller is responsible for storing this in a durable, server-side store keyed by id (the credential ID) and associated with user_id.

Fields

id: Vec<u8>

Opaque byte string that uniquely identifies this credential. Produced by the authenticator during registration.

public_key: PublicKey

The authenticator’s public key in the format signalled during registration.

sign_count: u32

Monotonically increasing counter maintained by the authenticator. Used to detect cloned authenticators.

user_id: Vec<u8>

Application-defined identifier for the user this credential belongs to.

rp_id: String

Relying party ID (e.g. "example.com"). Stored so authentication can verify the credential is bound to this RP.

created_at: SystemTime

When this credential was first registered.

backup_eligible: bool

Whether this credential is eligible for backup to a platform sync service (BE flag, §6.1 bit 3).

This value is immutable per spec — the authenticator sets it once at registration and it must not change in subsequent ceremonies. A change in backup_eligible between registration and authentication is treated as a credential substitution attempt and rejected with crate::error::WebAuthnError::BackupEligibilityChanged.

backup_state: bool

Whether this credential is currently backed up (BS flag, §6.1 bit 4).

This value may change between ceremonies as the user’s backup state varies. After a successful authentication ceremony, update this field to AuthenticationResult.backup_state before persisting the credential.

Trait Implementations

impl Clone for Credential

fn clone(&self) -> Credential

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Credential

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

Formats the value using the given formatter.