package lnwire import ( "fmt" "io" "github.com/roasbeef/btcd/wire" "google.golang.org/grpc/codes" ) // ErrorCode represents the short error code for each of the defined errors // within the Lightning Network protocol spec. type ErrorCode uint16 // ToGrpcCode is used to generate gRPC specific code which will be propagated // to the ln rpc client. This code is used to have more detailed view of what // goes wrong and also in order to have the ability pragmatically determine // the error and take specific actions on the client side. func (e ErrorCode) ToGrpcCode() codes.Code { return (codes.Code)(e) + 100 } const ( // ErrorMaxPendingChannels is returned by remote peer when the number // of active pending channels exceeds their maximum policy limit. ErrorMaxPendingChannels ErrorCode = 1 ) // ErrorGeneric represents a generic error bound to an exact channel. The // message format is purposefully general in order to allow expression of a wide // array of possible errors. Each ErrorGeneric message is directed at a particular // open channel referenced by ChannelPoint. type ErrorGeneric struct { // ChannelPoint references the active channel in which the error // occurred within. A ChannelPoint of zeroHash:0 denotes this error // applies to the entire established connection. ChannelPoint *wire.OutPoint // PendingChannelID allows peers communicate errors in the context of a // particular pending channel. With this field, once a peer reads an // ErrorGeneric message with the PendingChannelID field set, then they // can forward the error to the fundingManager who can handle it // properly. PendingChannelID uint64 // Code is the short error ID which describes the nature of the error. Code ErrorCode // Problem is a human-readable string further elaborating upon the // nature of the exact error. The maximum allowed length of this // message is 8192 bytes. Problem string } // NewErrorGeneric creates a new ErrorGeneric message. func NewErrorGeneric() *ErrorGeneric { return &ErrorGeneric{} } // A compile time check to ensure ErrorGeneric implements the lnwire.Message // interface. var _ Message = (*ErrorGeneric)(nil) // Decode deserializes a serialized ErrorGeneric message stored in the // passed io.Reader observing the specified protocol version. // // This is part of the lnwire.Message interface. func (c *ErrorGeneric) Decode(r io.Reader, pver uint32) error { // ChannelPoint(8) // Problem err := readElements(r, &c.ChannelPoint, &c.Code, &c.Problem, &c.PendingChannelID, ) if err != nil { return err } return nil } // Encode serializes the target ErrorGeneric into the passed io.Writer // observing the protocol version specified. // // This is part of the lnwire.Message interface. func (c *ErrorGeneric) Encode(w io.Writer, pver uint32) error { err := writeElements(w, c.ChannelPoint, c.Code, c.Problem, c.PendingChannelID, ) if err != nil { return err } return nil } // Command returns the integer uniquely identifying an ErrorGeneric message on // the wire. // // This is part of the lnwire.Message interface. func (c *ErrorGeneric) Command() uint32 { return CmdErrorGeneric } // MaxPayloadLength returns the maximum allowed payload size for a // ErrorGeneric complete message observing the specified protocol version. // // This is part of the lnwire.Message interface. func (c *ErrorGeneric) MaxPayloadLength(uint32) uint32 { // 8+8192 return 8208 } // Validate performs any necessary sanity checks to ensure all fields present // on the ErrorGeneric are valid. // // This is part of the lnwire.Message interface. func (c *ErrorGeneric) Validate() error { if len(c.Problem) > 8192 { return fmt.Errorf("problem string length too long") } // We're good! return nil }