pase

Documentation

Overview

Package pase implements the device (responder) side of Matter PASE — the Secure Channel exchange that turns the setup passcode into an encrypted session, using SPAKE2+ (spec §4.13 / §3.10):

commissioner → PBKDFParamRequest    →  we reply PBKDFParamResponse (salt, iter)
commissioner → Pake1 (pA)           →  we reply Pake2 (pB, cB)
commissioner → Pake3 (cA)           →  we verify and reply StatusReport

On success both sides hold the shared secret Ke, from which the session keys are derived. Those keys then encrypt the operational exchanges.

Index

• type Established
• type Responder
  • func New(log *logger.Logger, passcode uint32) (*Responder, error)
  • func (r *Responder) Handle(in *message.Inbound) []message.Outbound
  • func (r *Responder) TakeEstablished() (*Established, bool)

Types

type Established

type Established struct {
	I2R                  []byte
	R2I                  []byte
	AttestationChallenge []byte
	LocalSessionID       uint16 // our responder session id
	PeerSessionID        uint16 // the commissioner's session id
}

Established carries the outcome of a successful PASE handshake: the session keys and the two session ids, for the secure (encrypted) session layer.

type Responder

type Responder struct {
	// contains filtered or unexported fields
}

Responder runs one PASE handshake at a time (a commissioning window admits a single commissioner).

func New

func New(log *logger.Logger, passcode uint32) (*Responder, error)

New builds a responder and precomputes the SPAKE2+ verifier (w0, L) from the passcode with a fresh salt — exactly what a device stores when its commissioning window opens.

func (*Responder) Handle

func (r *Responder) Handle(in *message.Inbound) []message.Outbound

Handle processes one inbound Secure Channel message and returns the messages to send back (already with the right exchange id and a piggybacked ack).

func (*Responder) TakeEstablished

func (r *Responder) TakeEstablished() (*Established, bool)

TakeEstablished returns (and clears) the session established by the last successful Pake3, if any.