Documentation
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Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // ErrOutputNotFound signals that the breached output could not be found // on the commitment transaction. ErrOutputNotFound = errors.New("unable to find output on commit tx") // ErrUnknownSweepAddrType signals that client provided an output that // was not p2wkh or p2wsh. ErrUnknownSweepAddrType = errors.New("sweep addr is not p2wkh or p2wsh") )
Functions ¶
func DisableLog ¶
func DisableLog()
DisableLog disables all library log output. Logging output is disabled by default until UseLogger is called.
Types ¶
type BlockFetcher ¶
type BlockFetcher interface {
// GetBlock fetches the block given the target block hash.
GetBlock(*chainhash.Hash) (*wire.MsgBlock, error)
}
BlockFetcher supports the ability to fetch blocks from the backend or network.
type BreachPunisher ¶
type BreachPunisher struct {
// contains filtered or unexported fields
}
BreachPunisher handles the responsibility of constructing and broadcasting justice transactions. Justice transactions are constructed from previously accepted state updates uploaded by the watchtower's clients.
func NewBreachPunisher ¶
func NewBreachPunisher(cfg *PunisherConfig) *BreachPunisher
NewBreachPunisher constructs a new BreachPunisher given a PunisherConfig.
func (*BreachPunisher) Punish ¶
func (p *BreachPunisher) Punish(desc *JusticeDescriptor, quit <-chan struct{}) error
Punish constructs a justice transaction given a JusticeDescriptor and publishes is it to the network.
type Config ¶
type Config struct {
// DB provides persistent access to the watchtower's accepted state
// updates such that they can be queried as new blocks arrive from the
// network.
DB DB
// EpochRegistrar supports the ability to register for events corresponding to
// newly created blocks.
EpochRegistrar EpochRegistrar
// BlockFetcher supports the ability to fetch blocks from the backend or
// network.
BlockFetcher BlockFetcher
// Punisher handles the responsibility of crafting and broadcasting
// justice transaction for any breached transactions.
Punisher Punisher
}
Config houses the Lookout's required resources to properly fulfill it's duty, including block fetching, querying accepted state updates, and construction and publication of justice transactions.
type DB ¶
type DB interface {
// GetLookoutTip returns the last block epoch at which the tower
// performed a match. If no match has been done, a nil epoch will be
// returned.
GetLookoutTip() (*chainntnfs.BlockEpoch, error)
// QueryMatches searches its database for any state updates matching the
// provided breach hints. If any matches are found, they will be
// returned along with encrypted blobs so that justice can be exacted.
QueryMatches([]wtdb.BreachHint) ([]wtdb.Match, error)
// SetLookoutTip writes the best epoch for which the watchtower has
// queried for breach hints.
SetLookoutTip(*chainntnfs.BlockEpoch) error
}
DB abstracts the required persistent calls expected by the lookout. DB provides the ability to search for state updates that correspond to breach transactions confirmed in a particular block.
type EpochRegistrar ¶
type EpochRegistrar interface {
// RegisterBlockEpochNtfn registers for a new block epoch subscription.
// The implementation must support historical dispatch, starting from
// the provided chainntnfs.BlockEpoch when it is non-nil. The
// notifications should be delivered in-order, and deliver reorged
// blocks.
RegisterBlockEpochNtfn(
*chainntnfs.BlockEpoch) (*chainntnfs.BlockEpochEvent, error)
}
EpochRegistrar supports the ability to register for events corresponding to newly created blocks.
type JusticeDescriptor ¶
type JusticeDescriptor struct {
// BreachedCommitTx is the commitment transaction that caused the breach
// to be detected.
BreachedCommitTx *wire.MsgTx
// SessionInfo contains the contract with the watchtower client and
// the prenegotiated terms they agreed to.
SessionInfo *wtdb.SessionInfo
// JusticeKit contains the decrypted blob and information required to
// construct the transaction scripts and witnesses.
JusticeKit *blob.JusticeKit
}
JusticeDescriptor contains the information required to sweep a breached channel on behalf of a victim. It supports the ability to create the justice transaction that sweeps the commitments and recover a cut of the channel for the watcher's eternal vigilance.
func (*JusticeDescriptor) CreateJusticeTxn ¶
func (p *JusticeDescriptor) CreateJusticeTxn() (*wire.MsgTx, error)
CreateJusticeTxn computes the justice transaction that sweeps a breaching commitment transaction. The justice transaction is constructed by assembling the witnesses using data provided by the client in a prior state update.
type Lookout ¶
type Lookout struct {
// contains filtered or unexported fields
}
Lookout will check any incoming blocks against the transactions found in the database, and in case of matches send the information needed to create a penalty transaction to the punisher.
type Punisher ¶
type Punisher interface {
// Punish accepts a JusticeDescriptor, constructs the justice
// transaction, and publishes the transaction to the network so it can
// be mined. The second parameter is a quit channel so that long-running
// operations required to track the confirmation of the transaction can
// be canceled on shutdown.
Punish(*JusticeDescriptor, <-chan struct{}) error
}
Punisher handles the construction and publication of justice transactions once they have been detected by the Service.
type PunisherConfig ¶
type PunisherConfig struct {
// PublishTx provides the ability to send a signed transaction to the
// network.
PublishTx func(*wire.MsgTx) error
}
PunisherConfig houses the resources required by the Punisher.
type Service ¶
type Service interface {
// Start safely starts up the Interface.
Start() error
// Stop safely stops the Interface.
Stop() error
}
Service abstracts the lookout functionality, supporting the ability to start and stop. All communication and actions are driven via the database or chain events.
Source Files