Struct CapabilityToken 

pub struct CapabilityToken {
    pub version: u8,
    pub issuer: Vec<u8>,
    pub audience: Option<Vec<u8>>,
    pub scopes: Vec<String>,
    pub expires_at: u64,
    pub nonce: String,
    pub proofs: Vec<ProofLink>,
    pub signature: Vec<u8>,
}

A CLASP capability token.

Token format: cap_<base64url(messagepack(CapabilityToken))>

Tokens form delegation chains where each child can only narrow the parent’s scopes, never widen them.

Fields

version: u8

Token version (currently 1)

issuer: Vec<u8>

Issuer’s public key (Ed25519, 32 bytes)

audience: Option<Vec<u8>>

Audience public key (None = bearer token)

scopes: Vec<String>

Scopes granted (same “action:pattern” format as existing CLASP scopes)

expires_at: u64

Expiration time (Unix timestamp, seconds)

nonce: String

Unique nonce to prevent replay

proofs: Vec<ProofLink>

Proof chain: signatures of parent tokens in the delegation chain

signature: Vec<u8>

Signature over the token payload (by issuer)

Implementations

impl CapabilityToken

pub fn create_root( signing_key: &SigningKey, scopes: Vec<String>, expires_at: u64, audience: Option<Vec<u8>>, ) -> Result<Self>

Create and sign a new root capability token (no parent).

pub fn delegate( &self, child_signing_key: &SigningKey, child_scopes: Vec<String>, expires_at: u64, audience: Option<Vec<u8>>, ) -> Result<Self>

Delegate this token to create a child with narrower scopes.

The child token can only have scopes that are a subset of this token’s scopes.

pub fn verify_signature(&self) -> Result<()>

Verify this token’s signature

pub fn is_expired(&self) -> bool

Check if the token is expired

pub fn chain_depth(&self) -> usize

Get the delegation chain depth. Chain depth is bounded at validation time. See pentest CAP-03: Chain Depth Bypass

pub fn encode(&self) -> Result<String>

Encode to the cap_<base64> wire format

pub fn decode(token: &str) -> Result<Self>

Decode from the cap_<base64> wire format

Trait Implementations

impl Clone for CapabilityToken

fn clone(&self) -> CapabilityToken

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CapabilityToken

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for CapabilityToken

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for CapabilityToken

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.