diff --git a/channeldb/migration12/invoices.go b/channeldb/migration12/invoices.go new file mode 100644 index 00000000..7c08a9c9 --- /dev/null +++ b/channeldb/migration12/invoices.go @@ -0,0 +1,234 @@ +package migration12 + +import ( + "bytes" + "encoding/binary" + "io" + "time" + + "github.com/btcsuite/btcd/wire" + "github.com/lightningnetwork/lnd/lntypes" + "github.com/lightningnetwork/lnd/lnwire" + "github.com/lightningnetwork/lnd/tlv" +) + +const ( + // MaxMemoSize is maximum size of the memo field within invoices stored + // in the database. + MaxMemoSize = 1024 + + // maxReceiptSize is the maximum size of the payment receipt stored + // within the database along side incoming/outgoing invoices. + maxReceiptSize = 1024 + + // MaxPaymentRequestSize is the max size of a payment request for + // this invoice. + // TODO(halseth): determine the max length payment request when field + // lengths are final. + MaxPaymentRequestSize = 4096 + + memoType tlv.Type = 0 + payReqType tlv.Type = 1 + createTimeType tlv.Type = 2 + settleTimeType tlv.Type = 3 + addIndexType tlv.Type = 4 + settleIndexType tlv.Type = 5 + preimageType tlv.Type = 6 + valueType tlv.Type = 7 + cltvDeltaType tlv.Type = 8 + expiryType tlv.Type = 9 + paymentAddrType tlv.Type = 10 + featuresType tlv.Type = 11 + invStateType tlv.Type = 12 + amtPaidType tlv.Type = 13 +) + +var ( + // invoiceBucket is the name of the bucket within the database that + // stores all data related to invoices no matter their final state. + // Within the invoice bucket, each invoice is keyed by its invoice ID + // which is a monotonically increasing uint32. + invoiceBucket = []byte("invoices") + + // Big endian is the preferred byte order, due to cursor scans over + // integer keys iterating in order. + byteOrder = binary.BigEndian +) + +// ContractState describes the state the invoice is in. +type ContractState uint8 + +// ContractTerm is a companion struct to the Invoice struct. This struct houses +// the necessary conditions required before the invoice can be considered fully +// settled by the payee. +type ContractTerm struct { + // PaymentPreimage is the preimage which is to be revealed in the + // occasion that an HTLC paying to the hash of this preimage is + // extended. + PaymentPreimage lntypes.Preimage + + // Value is the expected amount of milli-satoshis to be paid to an HTLC + // which can be satisfied by the above preimage. + Value lnwire.MilliSatoshi + + // State describes the state the invoice is in. + State ContractState +} + +// Invoice is a payment invoice generated by a payee in order to request +// payment for some good or service. The inclusion of invoices within Lightning +// creates a payment work flow for merchants very similar to that of the +// existing financial system within PayPal, etc. Invoices are added to the +// database when a payment is requested, then can be settled manually once the +// payment is received at the upper layer. For record keeping purposes, +// invoices are never deleted from the database, instead a bit is toggled +// denoting the invoice has been fully settled. Within the database, all +// invoices must have a unique payment hash which is generated by taking the +// sha256 of the payment preimage. +type Invoice struct { + // Memo is an optional memo to be stored along side an invoice. The + // memo may contain further details pertaining to the invoice itself, + // or any other message which fits within the size constraints. + Memo []byte + + // PaymentRequest is an optional field where a payment request created + // for this invoice can be stored. + PaymentRequest []byte + + // FinalCltvDelta is the minimum required number of blocks before htlc + // expiry when the invoice is accepted. + FinalCltvDelta int32 + + // Expiry defines how long after creation this invoice should expire. + Expiry time.Duration + + // CreationDate is the exact time the invoice was created. + CreationDate time.Time + + // SettleDate is the exact time the invoice was settled. + SettleDate time.Time + + // Terms are the contractual payment terms of the invoice. Once all the + // terms have been satisfied by the payer, then the invoice can be + // considered fully fulfilled. + // + // TODO(roasbeef): later allow for multiple terms to fulfill the final + // invoice: payment fragmentation, etc. + Terms ContractTerm + + // AddIndex is an auto-incrementing integer that acts as a + // monotonically increasing sequence number for all invoices created. + // Clients can then use this field as a "checkpoint" of sorts when + // implementing a streaming RPC to notify consumers of instances where + // an invoice has been added before they re-connected. + // + // NOTE: This index starts at 1. + AddIndex uint64 + + // SettleIndex is an auto-incrementing integer that acts as a + // monotonically increasing sequence number for all settled invoices. + // Clients can then use this field as a "checkpoint" of sorts when + // implementing a streaming RPC to notify consumers of instances where + // an invoice has been settled before they re-connected. + // + // NOTE: This index starts at 1. + SettleIndex uint64 + + // AmtPaid is the final amount that we ultimately accepted for pay for + // this invoice. We specify this value independently as it's possible + // that the invoice originally didn't specify an amount, or the sender + // overpaid. + AmtPaid lnwire.MilliSatoshi + + // Htlcs records all htlcs that paid to this invoice. Some of these + // htlcs may have been marked as canceled. + Htlcs []byte +} + +// LegacyDeserializeInvoice decodes an invoice from the passed io.Reader using +// the pre-TLV serialization. +// +// nolint: dupl +func LegacyDeserializeInvoice(r io.Reader) (Invoice, error) { + var err error + invoice := Invoice{} + + // TODO(roasbeef): use read full everywhere + invoice.Memo, err = wire.ReadVarBytes(r, 0, MaxMemoSize, "") + if err != nil { + return invoice, err + } + _, err = wire.ReadVarBytes(r, 0, maxReceiptSize, "") + if err != nil { + return invoice, err + } + + invoice.PaymentRequest, err = wire.ReadVarBytes(r, 0, MaxPaymentRequestSize, "") + if err != nil { + return invoice, err + } + + if err := binary.Read(r, byteOrder, &invoice.FinalCltvDelta); err != nil { + return invoice, err + } + + var expiry int64 + if err := binary.Read(r, byteOrder, &expiry); err != nil { + return invoice, err + } + invoice.Expiry = time.Duration(expiry) + + birthBytes, err := wire.ReadVarBytes(r, 0, 300, "birth") + if err != nil { + return invoice, err + } + if err := invoice.CreationDate.UnmarshalBinary(birthBytes); err != nil { + return invoice, err + } + + settledBytes, err := wire.ReadVarBytes(r, 0, 300, "settled") + if err != nil { + return invoice, err + } + if err := invoice.SettleDate.UnmarshalBinary(settledBytes); err != nil { + return invoice, err + } + + if _, err := io.ReadFull(r, invoice.Terms.PaymentPreimage[:]); err != nil { + return invoice, err + } + var scratch [8]byte + if _, err := io.ReadFull(r, scratch[:]); err != nil { + return invoice, err + } + invoice.Terms.Value = lnwire.MilliSatoshi(byteOrder.Uint64(scratch[:])) + + if err := binary.Read(r, byteOrder, &invoice.Terms.State); err != nil { + return invoice, err + } + + if err := binary.Read(r, byteOrder, &invoice.AddIndex); err != nil { + return invoice, err + } + if err := binary.Read(r, byteOrder, &invoice.SettleIndex); err != nil { + return invoice, err + } + if err := binary.Read(r, byteOrder, &invoice.AmtPaid); err != nil { + return invoice, err + } + + invoice.Htlcs, err = deserializeHtlcs(r) + if err != nil { + return Invoice{}, err + } + + return invoice, nil +} + +// deserializeHtlcs reads a list of invoice htlcs from a reader and returns it +// as a flattened byte slice. +func deserializeHtlcs(r io.Reader) ([]byte, error) { + var b bytes.Buffer + _, err := io.Copy(&b, r) + return b.Bytes(), err +}