4deb922c9d
Although it is possible to get the command name for each msg type by creating an instances of the type and calling the Command method against it, it's slightly more efficient to simply allows callers to have direct access to the exported constants. This is currently really useful for the reject message since callers need to be able to examine the command type to determine whether or not the hash field needs to be included.
141 lines
4.2 KiB
Go
141 lines
4.2 KiB
Go
// Copyright (c) 2014 Conformal Systems LLC.
|
|
// Use of this source code is governed by an ISC
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package btcwire
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
)
|
|
|
|
// BloomUpdateType specifies how the filter is updated when a match is found
|
|
type BloomUpdateType uint8
|
|
|
|
const (
|
|
// BloomUpdateNone indicates the filter is not adjusted when a match is
|
|
// found.
|
|
BloomUpdateNone BloomUpdateType = 0
|
|
|
|
// BloomUpdateAll indicates if the filter matches any data element in a
|
|
// public key script, the outpoint is serialized and inserted into the
|
|
// filter.
|
|
BloomUpdateAll BloomUpdateType = 1
|
|
|
|
// BloomUpdateP2PubkeyOnly indicates if the filter matches a data
|
|
// element in a public key script and the script is of the standard
|
|
// pay-to-pubkey or multisig, the outpoint is serialized and inserted
|
|
// into the filter.
|
|
BloomUpdateP2PubkeyOnly BloomUpdateType = 2
|
|
)
|
|
|
|
const (
|
|
// MaxFilterLoadHashFuncs is the maximum number of hash functions to
|
|
// load into the Bloom filter.
|
|
MaxFilterLoadHashFuncs = 50
|
|
|
|
// MaxFilterLoadFilterSize is the maximum size in bytes a filter may be.
|
|
MaxFilterLoadFilterSize = 36000
|
|
)
|
|
|
|
// MsgFilterLoad implements the Message interface and represents a bitcoin
|
|
// filterload message which is used to reset a Bloom filter.
|
|
//
|
|
// This message was not added until protocol version BIP0037Version.
|
|
type MsgFilterLoad struct {
|
|
Filter []byte
|
|
HashFuncs uint32
|
|
Tweak uint32
|
|
Flags BloomUpdateType
|
|
}
|
|
|
|
// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
|
|
// This is part of the Message interface implementation.
|
|
func (msg *MsgFilterLoad) BtcDecode(r io.Reader, pver uint32) error {
|
|
if pver < BIP0037Version {
|
|
str := fmt.Sprintf("filterload message invalid for protocol "+
|
|
"version %d", pver)
|
|
return messageError("MsgFilterLoad.BtcDecode", str)
|
|
}
|
|
|
|
var err error
|
|
msg.Filter, err = readVarBytes(r, pver, MaxFilterLoadFilterSize,
|
|
"filterload filter size")
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
err = readElements(r, &msg.HashFuncs, &msg.Tweak, &msg.Flags)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if msg.HashFuncs > MaxFilterLoadHashFuncs {
|
|
str := fmt.Sprintf("too many filter hash functions for message "+
|
|
"[count %v, max %v]", msg.HashFuncs, MaxFilterLoadHashFuncs)
|
|
return messageError("MsgFilterLoad.BtcDecode", str)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
|
|
// This is part of the Message interface implementation.
|
|
func (msg *MsgFilterLoad) BtcEncode(w io.Writer, pver uint32) error {
|
|
if pver < BIP0037Version {
|
|
str := fmt.Sprintf("filterload message invalid for protocol "+
|
|
"version %d", pver)
|
|
return messageError("MsgFilterLoad.BtcEncode", str)
|
|
}
|
|
|
|
size := len(msg.Filter)
|
|
if size > MaxFilterLoadFilterSize {
|
|
str := fmt.Sprintf("filterload filter size too large for message "+
|
|
"[size %v, max %v]", size, MaxFilterLoadFilterSize)
|
|
return messageError("MsgFilterLoad.BtcEncode", str)
|
|
}
|
|
|
|
if msg.HashFuncs > MaxFilterLoadHashFuncs {
|
|
str := fmt.Sprintf("too many filter hash functions for message "+
|
|
"[count %v, max %v]", msg.HashFuncs, MaxFilterLoadHashFuncs)
|
|
return messageError("MsgFilterLoad.BtcEncode", str)
|
|
}
|
|
|
|
err := writeVarBytes(w, pver, msg.Filter)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
err = writeElements(w, msg.HashFuncs, msg.Tweak, msg.Flags)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Command returns the protocol command string for the message. This is part
|
|
// of the Message interface implementation.
|
|
func (msg *MsgFilterLoad) Command() string {
|
|
return CmdFilterLoad
|
|
}
|
|
|
|
// MaxPayloadLength returns the maximum length the payload can be for the
|
|
// receiver. This is part of the Message interface implementation.
|
|
func (msg *MsgFilterLoad) MaxPayloadLength(pver uint32) uint32 {
|
|
// Num filter bytes (varInt) + filter + 4 bytes hash funcs +
|
|
// 4 bytes tweak + 1 byte flags.
|
|
return uint32(VarIntSerializeSize(MaxFilterLoadFilterSize)) +
|
|
MaxFilterLoadFilterSize + 9
|
|
}
|
|
|
|
// NewMsgFilterLoad returns a new bitcoin filterload message that conforms to
|
|
// the Message interface. See MsgFilterLoad for details.
|
|
func NewMsgFilterLoad(filter []byte, hashFuncs uint32, tweak uint32, flags BloomUpdateType) *MsgFilterLoad {
|
|
return &MsgFilterLoad{
|
|
Filter: filter,
|
|
HashFuncs: hashFuncs,
|
|
Tweak: tweak,
|
|
Flags: flags,
|
|
}
|
|
}
|