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keyexchange

package

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Versions in this module

v1

v1.12.6

Jul 15, 2026

Changes in this version

type Crypto

+ func (c *Crypto) WouldAcceptNonce(counter uint64) bool

v1.12.5

Jul 13, 2026

v1.12.4

Jun 29, 2026

v1.12.3

Jun 23, 2026

v1.12.2

Jun 22, 2026

v1.12.1

Jun 21, 2026

v1.12.0

Jun 21, 2026

Changes in this version

+ const AgedCryptoFastDropAge

+ const DecryptFailDropGrace

+ const DecryptFailDropThreshold

+ const DuplicateHandshakeDebounce

+ const HKDFInfo

+ const KeyExchangeReplyMinInterval

+ const KeyExchangeReplyStaleThreshold

+ const MaxCryptoPeers

+ const MaxRekeyAttempts

+ const OutsideWindowDropGrace

+ const OutsideWindowDropThreshold

+ const RekeyRelayFallbackAfter

+ const RekeyRetransmitInterval

+ const ReplayDropGrace

+ const ReplayDropThreshold

+ const ReplayWindowSize

+ const SalvageMaxAge

+ const SalvageMaxEntries

+ var ErrNoKey = errors.New("keyexchange: no key installed for peer")

+ var ErrNotReady = errors.New("keyexchange: crypto installed but not ready")

+ type Crypto struct

+ AEAD cipher.AEAD

+ Authenticated bool

+ CreatedAt time.Time

+ DecryptFailCount int

+ MaxRecvNonce uint64

+ Nonce uint64

+ NoncePrefix [4]byte

+ OutsideWindowCount int

+ PeerX25519Key [32]byte

+ Ready bool

+ ReplayBitmap [ReplayWindowSize / 64]uint64

+ ReplayCount int

+ ReplayMu sync.Mutex

+ Salvage []SalvageEntry

+ SalvageMu sync.Mutex

+ func (c *Crypto) CheckAndRecordNonce(counter uint64) bool

+ func (c *Crypto) SetReplayBit(counter uint64)

+ func (c *Crypto) UndoReplayBit(counter uint64)

+ type EventPublisher func(topic string, payload map[string]any)

+ type FrameSender func(peerNodeID uint32, addr *net.UDPAddr, frame []byte) error

+ type Manager struct

+ func New(store *Store) *Manager

+ func (m *Manager) BuildAuthFrame() []byte

+ func (m *Manager) BuildUnauthFrame() []byte

+ func (m *Manager) ClearPendingRekey(peerNodeID uint32)

+ func (m *Manager) ClearRekeyGaveUp(peerNodeID uint32)

+ func (m *Manager) DeriveSecret(peerPubKeyBytes []byte) (*Crypto, error)

+ func (m *Manager) GetPeerPubKey(nodeID uint32) (ed25519.PublicKey, error)

+ func (m *Manager) HandleAuthFrame(data []byte, from *net.UDPAddr, fromRelay bool) bool

+ func (m *Manager) HandleUnauthFrame(data []byte, from *net.UDPAddr, fromRelay bool) bool

+ func (m *Manager) HasIdentity() bool

+ func (m *Manager) HasPeerPubKey(nodeID uint32) bool

+ func (m *Manager) Identity() *crypto.Identity

+ func (m *Manager) InboundDecryptStale(peerNodeID uint32) bool

+ func (m *Manager) InjectPendingRekeyForTest(peerNodeID uint32, st *PendingRekeyState)

+ func (m *Manager) InvalidatePeerPubKey(nodeID uint32)

+ func (m *Manager) LastInboundDecryptHas(peerNodeID uint32) bool

+ func (m *Manager) Loop(ctx context.Context)

+ func (m *Manager) MarkPendingRekey(peerNodeID uint32) bool

+ func (m *Manager) MarkReplyKeyExchangeSent(peerNodeID uint32) bool

+ func (m *Manager) PeerInRekeyGaveUp(peerNodeID uint32) bool

+ func (m *Manager) PendingRekeyAttempts(peerNodeID uint32) int

+ func (m *Manager) PendingRekeyForTest(peerNodeID uint32) *PendingRekeyState

+ func (m *Manager) PendingRekeyHas(peerNodeID uint32) bool

+ func (m *Manager) PrivKey() *ecdh.PrivateKey

+ func (m *Manager) PubKey() []byte

+ func (m *Manager) RecordInboundDecrypt(peerNodeID uint32)

+ func (m *Manager) RekeyRetransmitTick()

+ func (m *Manager) RemovePeer(nodeID uint32)

+ func (m *Manager) ResetPendingRekeyAttempts(peerNodeID uint32)

+ func (m *Manager) SendKeyExchangeToNode(peerNodeID uint32)

+ func (m *Manager) SetAddrLookup(f PeerAddrLookup)

+ func (m *Manager) SetIdentity(id *crypto.Identity)

+ func (m *Manager) SetLastInboundDecryptForTest(peerNodeID uint32, t time.Time)

+ func (m *Manager) SetLocalNodeIDFn(f func() uint32)

+ func (m *Manager) SetPeerPubKey(nodeID uint32, pk ed25519.PublicKey)

+ func (m *Manager) SetPeerVerifyFunc(f VerifyFunc)

+ func (m *Manager) SetPostInstallHook(h PostInstallHook)

+ func (m *Manager) SetPreRetransmitHook(h PreRetransmitHook)

+ func (m *Manager) SetPublisher(p EventPublisher)

+ func (m *Manager) SetReplyWhitelist(nodeIDs []uint32)

+ func (m *Manager) SetReplyWhitelistMatchAll(on bool)

+ func (m *Manager) SetSender(s FrameSender)

+ func (m *Manager) SetX25519Keys(priv *ecdh.PrivateKey, pub []byte)

+ func (m *Manager) Store() *Store

+ type PeerAddrLookup func(peerNodeID uint32) *net.UDPAddr

+ type PendingRekeyState struct

+ Attempts int

+ FirstSentAt time.Time

+ LastSentAt time.Time

+ type PostInstallEvent struct

+ Authenticated bool

+ From *net.UDPAddr

+ FromRelay bool

+ HadCrypto bool

+ KeyChanged bool

+ NewCrypto *Crypto

+ OldCrypto *Crypto

+ PeerEd25519 ed25519.PublicKey

+ PeerNodeID uint32

+ type PostInstallHook func(ev PostInstallEvent)

+ type PreRetransmitHook func(peerNodeID uint32, attempt int)

+ type SalvageEntry struct

+ Plaintext []byte

+ When time.Time

+ type Store struct

+ EncryptFail atomic.Uint64

+ EncryptOK atomic.Uint64

+ func NewStore() *Store

+ func (s *Store) CompareAndDrop(peerNodeID uint32, expected *Crypto) bool

+ func (s *Store) DrainSalvage(c *Crypto) []SalvageEntry

+ func (s *Store) Drop(peerNodeID uint32)

+ func (s *Store) Get(peerNodeID uint32) *Crypto

+ func (s *Store) Has(peerNodeID uint32) bool

+ func (s *Store) Install(peerNodeID uint32, c *Crypto)

+ func (s *Store) IsReady(peerNodeID uint32) bool

+ func (s *Store) Len() int

+ func (s *Store) LocalNodeID() uint32

+ func (s *Store) PeerIDs() []uint32

+ func (s *Store) RecordSalvage(c *Crypto, plaintext []byte)

+ func (s *Store) SetLocalNodeID(id uint32)

+ func (s *Store) ShouldDropOnDecryptFail(peerNodeID uint32, c *Crypto) bool

+ func (s *Store) ShouldDropOnOutsideWindow(peerNodeID uint32, c *Crypto) bool

+ func (s *Store) ShouldDropOnReplay(peerNodeID uint32, c *Crypto) bool

+ type VerifyFunc func(nodeID uint32) (ed25519.PublicKey, error)