lnd.xprv/lnwire/onion_error.go
2020-12-04 23:07:53 +08:00

1429 lines
41 KiB
Go

package lnwire
import (
"bufio"
"crypto/sha256"
"encoding/binary"
"fmt"
"io"
"bytes"
"github.com/davecgh/go-spew/spew"
"github.com/go-errors/errors"
"github.com/lightningnetwork/lnd/tlv"
)
// FailureMessage represents the onion failure object identified by its unique
// failure code.
type FailureMessage interface {
// Code returns a failure code describing the exact nature of the
// error.
Code() FailCode
// Error returns a human readable string describing the error. With
// this method, the FailureMessage interface meets the built-in error
// interface.
Error() string
}
// FailureMessageLength is the size of the failure message plus the size of
// padding. The FailureMessage message should always be EXACTLY this size.
const FailureMessageLength = 256
const (
// FlagBadOnion error flag describes an unparsable, encrypted by
// previous node.
FlagBadOnion FailCode = 0x8000
// FlagPerm error flag indicates a permanent failure.
FlagPerm FailCode = 0x4000
// FlagNode error flag indicates a node failure.
FlagNode FailCode = 0x2000
// FlagUpdate error flag indicates a new channel update is enclosed
// within the error.
FlagUpdate FailCode = 0x1000
)
// FailCode specifies the precise reason that an upstream HTLC was canceled.
// Each UpdateFailHTLC message carries a FailCode which is to be passed
// backwards, encrypted at each step back to the source of the HTLC within the
// route.
type FailCode uint16
// The currently defined onion failure types within this current version of the
// Lightning protocol.
const (
CodeNone FailCode = 0
CodeInvalidRealm = FlagBadOnion | 1
CodeTemporaryNodeFailure = FlagNode | 2
CodePermanentNodeFailure = FlagPerm | FlagNode | 2
CodeRequiredNodeFeatureMissing = FlagPerm | FlagNode | 3
CodeInvalidOnionVersion = FlagBadOnion | FlagPerm | 4
CodeInvalidOnionHmac = FlagBadOnion | FlagPerm | 5
CodeInvalidOnionKey = FlagBadOnion | FlagPerm | 6
CodeTemporaryChannelFailure = FlagUpdate | 7
CodePermanentChannelFailure = FlagPerm | 8
CodeRequiredChannelFeatureMissing = FlagPerm | 9
CodeUnknownNextPeer = FlagPerm | 10
CodeAmountBelowMinimum = FlagUpdate | 11
CodeFeeInsufficient = FlagUpdate | 12
CodeIncorrectCltvExpiry = FlagUpdate | 13
CodeExpiryTooSoon = FlagUpdate | 14
CodeChannelDisabled = FlagUpdate | 20
CodeIncorrectOrUnknownPaymentDetails = FlagPerm | 15
CodeIncorrectPaymentAmount = FlagPerm | 16
CodeFinalExpiryTooSoon FailCode = 17
CodeFinalIncorrectCltvExpiry FailCode = 18
CodeFinalIncorrectHtlcAmount FailCode = 19
CodeExpiryTooFar FailCode = 21
CodeInvalidOnionPayload = FlagPerm | 22
CodeMPPTimeout FailCode = 23
)
// String returns the string representation of the failure code.
func (c FailCode) String() string {
switch c {
case CodeInvalidRealm:
return "InvalidRealm"
case CodeTemporaryNodeFailure:
return "TemporaryNodeFailure"
case CodePermanentNodeFailure:
return "PermanentNodeFailure"
case CodeRequiredNodeFeatureMissing:
return "RequiredNodeFeatureMissing"
case CodeInvalidOnionVersion:
return "InvalidOnionVersion"
case CodeInvalidOnionHmac:
return "InvalidOnionHmac"
case CodeInvalidOnionKey:
return "InvalidOnionKey"
case CodeTemporaryChannelFailure:
return "TemporaryChannelFailure"
case CodePermanentChannelFailure:
return "PermanentChannelFailure"
case CodeRequiredChannelFeatureMissing:
return "RequiredChannelFeatureMissing"
case CodeUnknownNextPeer:
return "UnknownNextPeer"
case CodeAmountBelowMinimum:
return "AmountBelowMinimum"
case CodeFeeInsufficient:
return "FeeInsufficient"
case CodeIncorrectCltvExpiry:
return "IncorrectCltvExpiry"
case CodeIncorrectPaymentAmount:
return "IncorrectPaymentAmount"
case CodeExpiryTooSoon:
return "ExpiryTooSoon"
case CodeChannelDisabled:
return "ChannelDisabled"
case CodeIncorrectOrUnknownPaymentDetails:
return "IncorrectOrUnknownPaymentDetails"
case CodeFinalExpiryTooSoon:
return "FinalExpiryTooSoon"
case CodeFinalIncorrectCltvExpiry:
return "FinalIncorrectCltvExpiry"
case CodeFinalIncorrectHtlcAmount:
return "FinalIncorrectHtlcAmount"
case CodeExpiryTooFar:
return "ExpiryTooFar"
case CodeInvalidOnionPayload:
return "InvalidOnionPayload"
case CodeMPPTimeout:
return "MPPTimeout"
default:
return "<unknown>"
}
}
// FailInvalidRealm is returned if the realm byte is unknown.
//
// NOTE: May be returned by any node in the payment route.
type FailInvalidRealm struct{}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailInvalidRealm) Error() string {
return f.Code().String()
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailInvalidRealm) Code() FailCode {
return CodeInvalidRealm
}
// FailTemporaryNodeFailure is returned if an otherwise unspecified transient
// error occurs for the entire node.
//
// NOTE: May be returned by any node in the payment route.
type FailTemporaryNodeFailure struct{}
// Code returns the failure unique code.
// NOTE: Part of the FailureMessage interface.
func (f *FailTemporaryNodeFailure) Code() FailCode {
return CodeTemporaryNodeFailure
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailTemporaryNodeFailure) Error() string {
return f.Code().String()
}
// FailPermanentNodeFailure is returned if an otherwise unspecified permanent
// error occurs for the entire node.
//
// NOTE: May be returned by any node in the payment route.
type FailPermanentNodeFailure struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailPermanentNodeFailure) Code() FailCode {
return CodePermanentNodeFailure
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailPermanentNodeFailure) Error() string {
return f.Code().String()
}
// FailRequiredNodeFeatureMissing is returned if a node has requirement
// advertised in its node_announcement features which were not present in the
// onion.
//
// NOTE: May be returned by any node in the payment route.
type FailRequiredNodeFeatureMissing struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailRequiredNodeFeatureMissing) Code() FailCode {
return CodeRequiredNodeFeatureMissing
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailRequiredNodeFeatureMissing) Error() string {
return f.Code().String()
}
// FailPermanentChannelFailure is return if an otherwise unspecified permanent
// error occurs for the outgoing channel (eg. channel (recently).
//
// NOTE: May be returned by any node in the payment route.
type FailPermanentChannelFailure struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailPermanentChannelFailure) Code() FailCode {
return CodePermanentChannelFailure
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailPermanentChannelFailure) Error() string {
return f.Code().String()
}
// FailRequiredChannelFeatureMissing is returned if the outgoing channel has a
// requirement advertised in its channel announcement features which were not
// present in the onion.
//
// NOTE: May only be returned by intermediate nodes.
type FailRequiredChannelFeatureMissing struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailRequiredChannelFeatureMissing) Code() FailCode {
return CodeRequiredChannelFeatureMissing
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailRequiredChannelFeatureMissing) Error() string {
return f.Code().String()
}
// FailUnknownNextPeer is returned if the next peer specified by the onion is
// not known.
//
// NOTE: May only be returned by intermediate nodes.
type FailUnknownNextPeer struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailUnknownNextPeer) Code() FailCode {
return CodeUnknownNextPeer
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailUnknownNextPeer) Error() string {
return f.Code().String()
}
// FailIncorrectPaymentAmount is returned if the amount paid is less than the
// amount expected, the final node MUST fail the HTLC. If the amount paid is
// more than twice the amount expected, the final node SHOULD fail the HTLC.
// This allows the sender to reduce information leakage by altering the amount,
// without allowing accidental gross overpayment.
//
// NOTE: May only be returned by the final node in the path.
type FailIncorrectPaymentAmount struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailIncorrectPaymentAmount) Code() FailCode {
return CodeIncorrectPaymentAmount
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailIncorrectPaymentAmount) Error() string {
return f.Code().String()
}
// FailIncorrectDetails is returned for two reasons:
//
// 1) if the payment hash has already been paid, the final node MAY treat the
// payment hash as unknown, or may succeed in accepting the HTLC. If the
// payment hash is unknown, the final node MUST fail the HTLC.
//
// 2) if the amount paid is less than the amount expected, the final node MUST
// fail the HTLC. If the amount paid is more than twice the amount expected,
// the final node SHOULD fail the HTLC. This allows the sender to reduce
// information leakage by altering the amount, without allowing accidental
// gross overpayment.
//
// NOTE: May only be returned by the final node in the path.
type FailIncorrectDetails struct {
// amount is the value of the extended HTLC.
amount MilliSatoshi
// height is the block height when the htlc was received.
height uint32
}
// NewFailIncorrectDetails makes a new instance of the FailIncorrectDetails
// error bound to the specified HTLC amount and acceptance height.
func NewFailIncorrectDetails(amt MilliSatoshi,
height uint32) *FailIncorrectDetails {
return &FailIncorrectDetails{
amount: amt,
height: height,
}
}
// Amount is the value of the extended HTLC.
func (f *FailIncorrectDetails) Amount() MilliSatoshi {
return f.amount
}
// Height is the block height when the htlc was received.
func (f *FailIncorrectDetails) Height() uint32 {
return f.height
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailIncorrectDetails) Code() FailCode {
return CodeIncorrectOrUnknownPaymentDetails
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailIncorrectDetails) Error() string {
return fmt.Sprintf(
"%v(amt=%v, height=%v)", CodeIncorrectOrUnknownPaymentDetails,
f.amount, f.height,
)
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailIncorrectDetails) Decode(r io.Reader, pver uint32) error {
err := ReadElement(r, &f.amount)
switch {
// This is an optional tack on that was added later in the protocol. As
// a result, older nodes may not include this value. We'll account for
// this by checking for io.EOF here which means that no bytes were read
// at all.
case err == io.EOF:
return nil
case err != nil:
return err
}
// At a later stage, the height field was also tacked on. We need to
// check for io.EOF here as well.
err = ReadElement(r, &f.height)
switch {
case err == io.EOF:
return nil
case err != nil:
return err
}
return nil
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailIncorrectDetails) Encode(w io.Writer, pver uint32) error {
return WriteElements(w, f.amount, f.height)
}
// FailFinalExpiryTooSoon is returned if the cltv_expiry is too low, the final
// node MUST fail the HTLC.
//
// NOTE: May only be returned by the final node in the path.
type FailFinalExpiryTooSoon struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailFinalExpiryTooSoon) Code() FailCode {
return CodeFinalExpiryTooSoon
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailFinalExpiryTooSoon) Error() string {
return f.Code().String()
}
// NewFinalExpiryTooSoon creates new instance of the FailFinalExpiryTooSoon.
func NewFinalExpiryTooSoon() *FailFinalExpiryTooSoon {
return &FailFinalExpiryTooSoon{}
}
// FailInvalidOnionVersion is returned if the onion version byte is unknown.
//
// NOTE: May be returned only by intermediate nodes.
type FailInvalidOnionVersion struct {
// OnionSHA256 hash of the onion blob which haven't been proceeded.
OnionSHA256 [sha256.Size]byte
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailInvalidOnionVersion) Error() string {
return fmt.Sprintf("InvalidOnionVersion(onion_sha=%x)", f.OnionSHA256[:])
}
// NewInvalidOnionVersion creates new instance of the FailInvalidOnionVersion.
func NewInvalidOnionVersion(onion []byte) *FailInvalidOnionVersion {
return &FailInvalidOnionVersion{OnionSHA256: sha256.Sum256(onion)}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailInvalidOnionVersion) Code() FailCode {
return CodeInvalidOnionVersion
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailInvalidOnionVersion) Decode(r io.Reader, pver uint32) error {
return ReadElement(r, f.OnionSHA256[:])
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailInvalidOnionVersion) Encode(w io.Writer, pver uint32) error {
return WriteElement(w, f.OnionSHA256[:])
}
// FailInvalidOnionHmac is return if the onion HMAC is incorrect.
//
// NOTE: May only be returned by intermediate nodes.
type FailInvalidOnionHmac struct {
// OnionSHA256 hash of the onion blob which haven't been proceeded.
OnionSHA256 [sha256.Size]byte
}
// NewInvalidOnionHmac creates new instance of the FailInvalidOnionHmac.
func NewInvalidOnionHmac(onion []byte) *FailInvalidOnionHmac {
return &FailInvalidOnionHmac{OnionSHA256: sha256.Sum256(onion)}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailInvalidOnionHmac) Code() FailCode {
return CodeInvalidOnionHmac
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailInvalidOnionHmac) Decode(r io.Reader, pver uint32) error {
return ReadElement(r, f.OnionSHA256[:])
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailInvalidOnionHmac) Encode(w io.Writer, pver uint32) error {
return WriteElement(w, f.OnionSHA256[:])
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailInvalidOnionHmac) Error() string {
return fmt.Sprintf("InvalidOnionHMAC(onion_sha=%x)", f.OnionSHA256[:])
}
// FailInvalidOnionKey is return if the ephemeral key in the onion is
// unparsable.
//
// NOTE: May only be returned by intermediate nodes.
type FailInvalidOnionKey struct {
// OnionSHA256 hash of the onion blob which haven't been proceeded.
OnionSHA256 [sha256.Size]byte
}
// NewInvalidOnionKey creates new instance of the FailInvalidOnionKey.
func NewInvalidOnionKey(onion []byte) *FailInvalidOnionKey {
return &FailInvalidOnionKey{OnionSHA256: sha256.Sum256(onion)}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailInvalidOnionKey) Code() FailCode {
return CodeInvalidOnionKey
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailInvalidOnionKey) Decode(r io.Reader, pver uint32) error {
return ReadElement(r, f.OnionSHA256[:])
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailInvalidOnionKey) Encode(w io.Writer, pver uint32) error {
return WriteElement(w, f.OnionSHA256[:])
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailInvalidOnionKey) Error() string {
return fmt.Sprintf("InvalidOnionKey(onion_sha=%x)", f.OnionSHA256[:])
}
// parseChannelUpdateCompatabilityMode will attempt to parse a channel updated
// encoded into an onion error payload in two ways. First, we'll try the
// compatibility oriented version wherein we'll _skip_ the length prefixing on
// the channel update message. Older versions of c-lighting do this so we'll
// attempt to parse these messages in order to retain compatibility. If we're
// unable to pull out a fully valid version, then we'll fall back to the
// regular parsing mechanism which includes the length prefix an NO type byte.
func parseChannelUpdateCompatabilityMode(r *bufio.Reader,
chanUpdate *ChannelUpdate, pver uint32) error {
// We'll peek out two bytes from the buffer without advancing the
// buffer so we can decide how to parse the remainder of it.
maybeTypeBytes, err := r.Peek(2)
if err != nil {
return err
}
// Some nodes well prefix an additional set of bytes in front of their
// channel updates. These bytes will _almost_ always be 258 or the type
// of the ChannelUpdate message.
typeInt := binary.BigEndian.Uint16(maybeTypeBytes)
if typeInt == MsgChannelUpdate {
// At this point it's likely the case that this is a channel
// update message with its type prefixed, so we'll snip off the
// first two bytes and parse it as normal.
var throwAwayTypeBytes [2]byte
_, err := r.Read(throwAwayTypeBytes[:])
if err != nil {
return err
}
}
// At this pint, we've either decided to keep the entire thing, or snip
// off the first two bytes. In either case, we can just read it as
// normal.
return chanUpdate.Decode(r, pver)
}
// FailTemporaryChannelFailure is if an otherwise unspecified transient error
// occurs for the outgoing channel (eg. channel capacity reached, too many
// in-flight htlcs)
//
// NOTE: May only be returned by intermediate nodes.
type FailTemporaryChannelFailure struct {
// Update is used to update information about state of the channel
// which caused the failure.
//
// NOTE: This field is optional.
Update *ChannelUpdate
}
// NewTemporaryChannelFailure creates new instance of the FailTemporaryChannelFailure.
func NewTemporaryChannelFailure(update *ChannelUpdate) *FailTemporaryChannelFailure {
return &FailTemporaryChannelFailure{Update: update}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailTemporaryChannelFailure) Code() FailCode {
return CodeTemporaryChannelFailure
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailTemporaryChannelFailure) Error() string {
if f.Update == nil {
return f.Code().String()
}
return fmt.Sprintf("TemporaryChannelFailure(update=%v)",
spew.Sdump(f.Update))
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailTemporaryChannelFailure) Decode(r io.Reader, pver uint32) error {
var length uint16
err := ReadElement(r, &length)
if err != nil {
return err
}
if length != 0 {
f.Update = &ChannelUpdate{}
return parseChannelUpdateCompatabilityMode(
bufio.NewReader(r), f.Update, pver,
)
}
return nil
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailTemporaryChannelFailure) Encode(w io.Writer, pver uint32) error {
var payload []byte
if f.Update != nil {
var bw bytes.Buffer
if err := f.Update.Encode(&bw, pver); err != nil {
return err
}
payload = bw.Bytes()
}
if err := WriteElement(w, uint16(len(payload))); err != nil {
return err
}
_, err := w.Write(payload)
return err
}
// FailAmountBelowMinimum is returned if the HTLC does not reach the current
// minimum amount, we tell them the amount of the incoming HTLC and the current
// channel setting for the outgoing channel.
//
// NOTE: May only be returned by the intermediate nodes in the path.
type FailAmountBelowMinimum struct {
// HtlcMsat is the wrong amount of the incoming HTLC.
HtlcMsat MilliSatoshi
// Update is used to update information about state of the channel
// which caused the failure.
Update ChannelUpdate
}
// NewAmountBelowMinimum creates new instance of the FailAmountBelowMinimum.
func NewAmountBelowMinimum(htlcMsat MilliSatoshi,
update ChannelUpdate) *FailAmountBelowMinimum {
return &FailAmountBelowMinimum{
HtlcMsat: htlcMsat,
Update: update,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailAmountBelowMinimum) Code() FailCode {
return CodeAmountBelowMinimum
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailAmountBelowMinimum) Error() string {
return fmt.Sprintf("AmountBelowMinimum(amt=%v, update=%v", f.HtlcMsat,
spew.Sdump(f.Update))
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailAmountBelowMinimum) Decode(r io.Reader, pver uint32) error {
if err := ReadElement(r, &f.HtlcMsat); err != nil {
return err
}
var length uint16
if err := ReadElement(r, &length); err != nil {
return err
}
f.Update = ChannelUpdate{}
return parseChannelUpdateCompatabilityMode(
bufio.NewReader(r), &f.Update, pver,
)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailAmountBelowMinimum) Encode(w io.Writer, pver uint32) error {
if err := WriteElement(w, f.HtlcMsat); err != nil {
return err
}
return writeOnionErrorChanUpdate(w, &f.Update, pver)
}
// FailFeeInsufficient is returned if the HTLC does not pay sufficient fee, we
// tell them the amount of the incoming HTLC and the current channel setting
// for the outgoing channel.
//
// NOTE: May only be returned by intermediate nodes.
type FailFeeInsufficient struct {
// HtlcMsat is the wrong amount of the incoming HTLC.
HtlcMsat MilliSatoshi
// Update is used to update information about state of the channel
// which caused the failure.
Update ChannelUpdate
}
// NewFeeInsufficient creates new instance of the FailFeeInsufficient.
func NewFeeInsufficient(htlcMsat MilliSatoshi,
update ChannelUpdate) *FailFeeInsufficient {
return &FailFeeInsufficient{
HtlcMsat: htlcMsat,
Update: update,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailFeeInsufficient) Code() FailCode {
return CodeFeeInsufficient
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailFeeInsufficient) Error() string {
return fmt.Sprintf("FeeInsufficient(htlc_amt==%v, update=%v", f.HtlcMsat,
spew.Sdump(f.Update))
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailFeeInsufficient) Decode(r io.Reader, pver uint32) error {
if err := ReadElement(r, &f.HtlcMsat); err != nil {
return err
}
var length uint16
if err := ReadElement(r, &length); err != nil {
return err
}
f.Update = ChannelUpdate{}
return parseChannelUpdateCompatabilityMode(
bufio.NewReader(r), &f.Update, pver,
)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailFeeInsufficient) Encode(w io.Writer, pver uint32) error {
if err := WriteElement(w, f.HtlcMsat); err != nil {
return err
}
return writeOnionErrorChanUpdate(w, &f.Update, pver)
}
// FailIncorrectCltvExpiry is returned if outgoing cltv value does not match
// the update add htlc's cltv expiry minus cltv expiry delta for the outgoing
// channel, we tell them the cltv expiry and the current channel setting for
// the outgoing channel.
//
// NOTE: May only be returned by intermediate nodes.
type FailIncorrectCltvExpiry struct {
// CltvExpiry is the wrong absolute timeout in blocks, after which
// outgoing HTLC expires.
CltvExpiry uint32
// Update is used to update information about state of the channel
// which caused the failure.
Update ChannelUpdate
}
// NewIncorrectCltvExpiry creates new instance of the FailIncorrectCltvExpiry.
func NewIncorrectCltvExpiry(cltvExpiry uint32,
update ChannelUpdate) *FailIncorrectCltvExpiry {
return &FailIncorrectCltvExpiry{
CltvExpiry: cltvExpiry,
Update: update,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailIncorrectCltvExpiry) Code() FailCode {
return CodeIncorrectCltvExpiry
}
func (f *FailIncorrectCltvExpiry) Error() string {
return fmt.Sprintf("IncorrectCltvExpiry(expiry=%v, update=%v",
f.CltvExpiry, spew.Sdump(f.Update))
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailIncorrectCltvExpiry) Decode(r io.Reader, pver uint32) error {
if err := ReadElement(r, &f.CltvExpiry); err != nil {
return err
}
var length uint16
if err := ReadElement(r, &length); err != nil {
return err
}
f.Update = ChannelUpdate{}
return parseChannelUpdateCompatabilityMode(
bufio.NewReader(r), &f.Update, pver,
)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailIncorrectCltvExpiry) Encode(w io.Writer, pver uint32) error {
if err := WriteElement(w, f.CltvExpiry); err != nil {
return err
}
return writeOnionErrorChanUpdate(w, &f.Update, pver)
}
// FailExpiryTooSoon is returned if the ctlv-expiry is too near, we tell them
// the current channel setting for the outgoing channel.
//
// NOTE: May only be returned by intermediate nodes.
type FailExpiryTooSoon struct {
// Update is used to update information about state of the channel
// which caused the failure.
Update ChannelUpdate
}
// NewExpiryTooSoon creates new instance of the FailExpiryTooSoon.
func NewExpiryTooSoon(update ChannelUpdate) *FailExpiryTooSoon {
return &FailExpiryTooSoon{
Update: update,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailExpiryTooSoon) Code() FailCode {
return CodeExpiryTooSoon
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailExpiryTooSoon) Error() string {
return fmt.Sprintf("ExpiryTooSoon(update=%v", spew.Sdump(f.Update))
}
// Decode decodes the failure from l stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailExpiryTooSoon) Decode(r io.Reader, pver uint32) error {
var length uint16
if err := ReadElement(r, &length); err != nil {
return err
}
f.Update = ChannelUpdate{}
return parseChannelUpdateCompatabilityMode(
bufio.NewReader(r), &f.Update, pver,
)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailExpiryTooSoon) Encode(w io.Writer, pver uint32) error {
return writeOnionErrorChanUpdate(w, &f.Update, pver)
}
// FailChannelDisabled is returned if the channel is disabled, we tell them the
// current channel setting for the outgoing channel.
//
// NOTE: May only be returned by intermediate nodes.
type FailChannelDisabled struct {
// Flags least-significant bit must be set to 0 if the creating node
// corresponds to the first node in the previously sent channel
// announcement and 1 otherwise.
Flags uint16
// Update is used to update information about state of the channel
// which caused the failure.
Update ChannelUpdate
}
// NewChannelDisabled creates new instance of the FailChannelDisabled.
func NewChannelDisabled(flags uint16, update ChannelUpdate) *FailChannelDisabled {
return &FailChannelDisabled{
Flags: flags,
Update: update,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailChannelDisabled) Code() FailCode {
return CodeChannelDisabled
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailChannelDisabled) Error() string {
return fmt.Sprintf("ChannelDisabled(flags=%v, update=%v", f.Flags,
spew.Sdump(f.Update))
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailChannelDisabled) Decode(r io.Reader, pver uint32) error {
if err := ReadElement(r, &f.Flags); err != nil {
return err
}
var length uint16
if err := ReadElement(r, &length); err != nil {
return err
}
f.Update = ChannelUpdate{}
return parseChannelUpdateCompatabilityMode(
bufio.NewReader(r), &f.Update, pver,
)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailChannelDisabled) Encode(w io.Writer, pver uint32) error {
if err := WriteElement(w, f.Flags); err != nil {
return err
}
return writeOnionErrorChanUpdate(w, &f.Update, pver)
}
// FailFinalIncorrectCltvExpiry is returned if the outgoing_cltv_value does not
// match the ctlv_expiry of the HTLC at the final hop.
//
// NOTE: might be returned by final node only.
type FailFinalIncorrectCltvExpiry struct {
// CltvExpiry is the wrong absolute timeout in blocks, after which
// outgoing HTLC expires.
CltvExpiry uint32
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailFinalIncorrectCltvExpiry) Error() string {
return fmt.Sprintf("FinalIncorrectCltvExpiry(expiry=%v)", f.CltvExpiry)
}
// NewFinalIncorrectCltvExpiry creates new instance of the
// FailFinalIncorrectCltvExpiry.
func NewFinalIncorrectCltvExpiry(cltvExpiry uint32) *FailFinalIncorrectCltvExpiry {
return &FailFinalIncorrectCltvExpiry{
CltvExpiry: cltvExpiry,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailFinalIncorrectCltvExpiry) Code() FailCode {
return CodeFinalIncorrectCltvExpiry
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailFinalIncorrectCltvExpiry) Decode(r io.Reader, pver uint32) error {
return ReadElement(r, &f.CltvExpiry)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailFinalIncorrectCltvExpiry) Encode(w io.Writer, pver uint32) error {
return WriteElement(w, f.CltvExpiry)
}
// FailFinalIncorrectHtlcAmount is returned if the amt_to_forward is higher
// than incoming_htlc_amt of the HTLC at the final hop.
//
// NOTE: May only be returned by the final node.
type FailFinalIncorrectHtlcAmount struct {
// IncomingHTLCAmount is the wrong forwarded htlc amount.
IncomingHTLCAmount MilliSatoshi
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailFinalIncorrectHtlcAmount) Error() string {
return fmt.Sprintf("FinalIncorrectHtlcAmount(amt=%v)",
f.IncomingHTLCAmount)
}
// NewFinalIncorrectHtlcAmount creates new instance of the
// FailFinalIncorrectHtlcAmount.
func NewFinalIncorrectHtlcAmount(amount MilliSatoshi) *FailFinalIncorrectHtlcAmount {
return &FailFinalIncorrectHtlcAmount{
IncomingHTLCAmount: amount,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailFinalIncorrectHtlcAmount) Code() FailCode {
return CodeFinalIncorrectHtlcAmount
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailFinalIncorrectHtlcAmount) Decode(r io.Reader, pver uint32) error {
return ReadElement(r, &f.IncomingHTLCAmount)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *FailFinalIncorrectHtlcAmount) Encode(w io.Writer, pver uint32) error {
return WriteElement(w, f.IncomingHTLCAmount)
}
// FailExpiryTooFar is returned if the CLTV expiry in the HTLC is too far in the
// future.
//
// NOTE: May be returned by any node in the payment route.
type FailExpiryTooFar struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailExpiryTooFar) Code() FailCode {
return CodeExpiryTooFar
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailExpiryTooFar) Error() string {
return f.Code().String()
}
// InvalidOnionPayload is returned if the hop could not process the TLV payload
// enclosed in the onion.
type InvalidOnionPayload struct {
// Type is the TLV type that caused the specific failure.
Type uint64
// Offset is the byte offset within the payload where the failure
// occurred.
Offset uint16
}
// NewInvalidOnionPayload initializes a new InvalidOnionPayload failure.
func NewInvalidOnionPayload(typ uint64, offset uint16) *InvalidOnionPayload {
return &InvalidOnionPayload{
Type: typ,
Offset: offset,
}
}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *InvalidOnionPayload) Code() FailCode {
return CodeInvalidOnionPayload
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *InvalidOnionPayload) Error() string {
return fmt.Sprintf("%v(type=%v, offset=%d)",
f.Code(), f.Type, f.Offset)
}
// Decode decodes the failure from bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *InvalidOnionPayload) Decode(r io.Reader, pver uint32) error {
var buf [8]byte
typ, err := tlv.ReadVarInt(r, &buf)
if err != nil {
return err
}
f.Type = typ
return ReadElements(r, &f.Offset)
}
// Encode writes the failure in bytes stream.
//
// NOTE: Part of the Serializable interface.
func (f *InvalidOnionPayload) Encode(w io.Writer, pver uint32) error {
var buf [8]byte
if err := tlv.WriteVarInt(w, f.Type, &buf); err != nil {
return err
}
return WriteElements(w, f.Offset)
}
// FailMPPTimeout is returned if the complete amount for a multi part payment
// was not received within a reasonable time.
//
// NOTE: May only be returned by the final node in the path.
type FailMPPTimeout struct{}
// Code returns the failure unique code.
//
// NOTE: Part of the FailureMessage interface.
func (f *FailMPPTimeout) Code() FailCode {
return CodeMPPTimeout
}
// Returns a human readable string describing the target FailureMessage.
//
// NOTE: Implements the error interface.
func (f *FailMPPTimeout) Error() string {
return f.Code().String()
}
// DecodeFailure decodes, validates, and parses the lnwire onion failure, for
// the provided protocol version.
func DecodeFailure(r io.Reader, pver uint32) (FailureMessage, error) {
// First, we'll parse out the encapsulated failure message itself. This
// is a 2 byte length followed by the payload itself.
var failureLength uint16
if err := ReadElement(r, &failureLength); err != nil {
return nil, fmt.Errorf("unable to read error len: %v", err)
}
if failureLength > FailureMessageLength {
return nil, fmt.Errorf("failure message is too "+
"long: %v", failureLength)
}
failureData := make([]byte, failureLength)
if _, err := io.ReadFull(r, failureData); err != nil {
return nil, fmt.Errorf("unable to full read payload of "+
"%v: %v", failureLength, err)
}
dataReader := bytes.NewReader(failureData)
return DecodeFailureMessage(dataReader, pver)
}
// DecodeFailureMessage decodes just the failure message, ignoring any padding
// that may be present at the end.
func DecodeFailureMessage(r io.Reader, pver uint32) (FailureMessage, error) {
// Once we have the failure data, we can obtain the failure code from
// the first two bytes of the buffer.
var codeBytes [2]byte
if _, err := io.ReadFull(r, codeBytes[:]); err != nil {
return nil, fmt.Errorf("unable to read failure code: %v", err)
}
failCode := FailCode(binary.BigEndian.Uint16(codeBytes[:]))
// Create the empty failure by given code and populate the failure with
// additional data if needed.
failure, err := makeEmptyOnionError(failCode)
if err != nil {
return nil, fmt.Errorf("unable to make empty error: %v", err)
}
// Finally, if this failure has a payload, then we'll read that now as
// well.
switch f := failure.(type) {
case Serializable:
if err := f.Decode(r, pver); err != nil {
return nil, fmt.Errorf("unable to decode error "+
"update (type=%T): %v", failure, err)
}
}
return failure, nil
}
// EncodeFailure encodes, including the necessary onion failure header
// information.
func EncodeFailure(w io.Writer, failure FailureMessage, pver uint32) error {
var failureMessageBuffer bytes.Buffer
err := EncodeFailureMessage(&failureMessageBuffer, failure, pver)
if err != nil {
return err
}
// The combined size of this message must be below the max allowed
// failure message length.
failureMessage := failureMessageBuffer.Bytes()
if len(failureMessage) > FailureMessageLength {
return fmt.Errorf("failure message exceed max "+
"available size: %v", len(failureMessage))
}
// Finally, we'll add some padding in order to ensure that all failure
// messages are fixed size.
pad := make([]byte, FailureMessageLength-len(failureMessage))
return WriteElements(w,
uint16(len(failureMessage)),
failureMessage,
uint16(len(pad)),
pad,
)
}
// EncodeFailureMessage encodes just the failure message without adding a length
// and padding the message for the onion protocol.
func EncodeFailureMessage(w io.Writer, failure FailureMessage, pver uint32) error {
// First, we'll write out the error code itself into the failure
// buffer.
var codeBytes [2]byte
code := uint16(failure.Code())
binary.BigEndian.PutUint16(codeBytes[:], code)
_, err := w.Write(codeBytes[:])
if err != nil {
return err
}
// Next, some message have an additional message payload, if this is
// one of those types, then we'll also encode the error payload as
// well.
switch failure := failure.(type) {
case Serializable:
if err := failure.Encode(w, pver); err != nil {
return err
}
}
return nil
}
// makeEmptyOnionError creates a new empty onion error of the proper concrete
// type based on the passed failure code.
func makeEmptyOnionError(code FailCode) (FailureMessage, error) {
switch code {
case CodeInvalidRealm:
return &FailInvalidRealm{}, nil
case CodeTemporaryNodeFailure:
return &FailTemporaryNodeFailure{}, nil
case CodePermanentNodeFailure:
return &FailPermanentNodeFailure{}, nil
case CodeRequiredNodeFeatureMissing:
return &FailRequiredNodeFeatureMissing{}, nil
case CodePermanentChannelFailure:
return &FailPermanentChannelFailure{}, nil
case CodeRequiredChannelFeatureMissing:
return &FailRequiredChannelFeatureMissing{}, nil
case CodeUnknownNextPeer:
return &FailUnknownNextPeer{}, nil
case CodeIncorrectOrUnknownPaymentDetails:
return &FailIncorrectDetails{}, nil
case CodeIncorrectPaymentAmount:
return &FailIncorrectPaymentAmount{}, nil
case CodeFinalExpiryTooSoon:
return &FailFinalExpiryTooSoon{}, nil
case CodeInvalidOnionVersion:
return &FailInvalidOnionVersion{}, nil
case CodeInvalidOnionHmac:
return &FailInvalidOnionHmac{}, nil
case CodeInvalidOnionKey:
return &FailInvalidOnionKey{}, nil
case CodeTemporaryChannelFailure:
return &FailTemporaryChannelFailure{}, nil
case CodeAmountBelowMinimum:
return &FailAmountBelowMinimum{}, nil
case CodeFeeInsufficient:
return &FailFeeInsufficient{}, nil
case CodeIncorrectCltvExpiry:
return &FailIncorrectCltvExpiry{}, nil
case CodeExpiryTooSoon:
return &FailExpiryTooSoon{}, nil
case CodeChannelDisabled:
return &FailChannelDisabled{}, nil
case CodeFinalIncorrectCltvExpiry:
return &FailFinalIncorrectCltvExpiry{}, nil
case CodeFinalIncorrectHtlcAmount:
return &FailFinalIncorrectHtlcAmount{}, nil
case CodeExpiryTooFar:
return &FailExpiryTooFar{}, nil
case CodeInvalidOnionPayload:
return &InvalidOnionPayload{}, nil
case CodeMPPTimeout:
return &FailMPPTimeout{}, nil
default:
return nil, errors.Errorf("unknown error code: %v", code)
}
}
// writeOnionErrorChanUpdate writes out a ChannelUpdate using the onion error
// format. The format is that we first write out the true serialized length of
// the channel update, followed by the serialized channel update itself.
func writeOnionErrorChanUpdate(w io.Writer, chanUpdate *ChannelUpdate,
pver uint32) error {
// First, we encode the channel update in a temporary buffer in order
// to get the exact serialized size.
var b bytes.Buffer
if err := chanUpdate.Encode(&b, pver); err != nil {
return err
}
// Now that we know the size, we can write the length out in the main
// writer.
updateLen := b.Len()
if err := WriteElement(w, uint16(updateLen)); err != nil {
return err
}
// With the length written, we'll then write out the serialized channel
// update.
if _, err := w.Write(b.Bytes()); err != nil {
return err
}
return nil
}