Struct CreatedFastCell 

pub struct CreatedFastCell {
    pub circ_id: u32,
    pub key_material: [u8; 20],
    pub derivative_key: [u8; 20],
    pub unused: Vec<u8>,
}

Response to CREATE_FAST circuit creation.

CREATED_FAST cells are sent by relays in response to CREATE_FAST cells. They contain the relay’s key material and a derivative key that proves the relay knows the shared secret.

Key Derivation

The shared key material is: client_key_material || relay_key_material This is used with KDF-TOR to derive encryption keys.

Wire Format

[ CircID ][ 6 (CREATED_FAST) ][ Key Material (20) ][ Derivative Key (20) ][ Padding ]

Fields

circ_id: u32

Circuit ID this response is for.

key_material: [u8; 20]

Relay’s random key material (20 bytes).

derivative_key: [u8; 20]

Hash proving relay knows the shared key (20 bytes).

unused: Vec<u8>

Unused padding bytes.

Implementations

impl CreatedFastCell

pub fn new(circ_id: u32, derivative_key: [u8; 20]) -> Self

Creates a new CREATED_FAST cell with random key material.

Arguments

• circ_id - Circuit ID this response is for
• derivative_key - Hash proving knowledge of shared key

pub fn with_key_material( circ_id: u32, key_material: [u8; 20], derivative_key: [u8; 20], ) -> Self

Creates a CREATED_FAST cell with specific key material.

Arguments

• circ_id - Circuit ID this response is for
• key_material - Relay’s 20 bytes of key material
• derivative_key - Hash proving knowledge of shared key

pub fn pack(&self, link_protocol: &LinkProtocol) -> Vec<u8>

Packs this cell into bytes for transmission.

pub fn unpack(payload: &[u8], circ_id: u32) -> Result<Self, Error>

Unpacks a CREATED_FAST cell from payload bytes.

Errors

Returns Error::Protocol if payload is too short.

Trait Implementations

impl Clone for CreatedFastCell

fn clone(&self) -> CreatedFastCell

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for CreatedFastCell

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

Formats the value using the given formatter.

impl PartialEq for CreatedFastCell

fn eq(&self, other: &CreatedFastCell) -> 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 StructuralPartialEq for CreatedFastCell