chaincfg

README

chaincfg

[] (https://travis-ci.org/btcsuite/btcd) ![ISC License] (http://img.shields.io/badge/license-ISC-blue.svg)

Package chaincfg defines chain configuration parameters for the three standard Bitcoin networks and provides the ability for callers to define their own custom Bitcoin networks.

Although this package was primarily written for btcd, it has intentionally been designed so it can be used as a standalone package for any projects needing to use parameters for the standard Bitcoin networks or for projects needing to define their own network.

Sample Use

package main

import (
	"flag"
	"fmt"
	"log"

	"github.com/btcsuite/btcutil"
	"github.com/btcsuite/btcd/chaincfg"
)

var testnet = flag.Bool("testnet", false, "operate on the testnet Bitcoin network")

// By default (without -testnet), use mainnet.
var chainParams = &chaincfg.MainNetParams

func main() {
	flag.Parse()

	// Modify active network parameters if operating on testnet.
	if *testnet {
		chainParams = &chaincfg.TestNet3Params
	}

	// later...

	// Create and print new payment address, specific to the active network.
	pubKeyHash := make([]byte, 20)
	addr, err := btcutil.NewAddressPubKeyHash(pubKeyHash, chainParams)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Println(addr)
}

Documentation

[] (http://godoc.org/github.com/btcsuite/btcd/chaincfg)

Full go doc style documentation for the project can be viewed online without installing this package by using the GoDoc site here.

You can also view the documentation locally once the package is installed with the godoc tool by running godoc -http=":6060" and pointing your browser to http://localhost:6060/pkg/github.com/btcsuite/btcd/chaincfg

Installation

$ go get github.com/btcsuite/btcd/chaincfg

GPG Verification Key

All official release tags are signed by Conformal so users can ensure the code has not been tampered with and is coming from the btcsuite developers. To verify the signature perform the following:

• Download the public key from the Conformal website at https://opensource.conformal.com/GIT-GPG-KEY-conformal.txt

• Import the public key into your GPG keyring:

  gpg --import GIT-GPG-KEY-conformal.txt
  

• Verify the release tag with the following command where TAG_NAME is a placeholder for the specific tag:

  git tag -v TAG_NAME
  

License

Package chaincfg is licensed under the copyfree ISC License.

Documentation

Overview

Package chaincfg defines chain configuration parameters.

In addition to the main Bitcoin network, which is intended for the transfer of monetary value, there also exists two currently active standard networks: regression test and testnet (version 3). These networks are incompatible with each other (each sharing a different genesis block) and software should handle errors where input intended for one network is used on an application instance running on a different network.

For library packages, chaincfg provides the ability to lookup chain parameters and encoding magics when passed a *Params. Older APIs not updated to the new convention of passing a *Params may lookup the parameters for a wire.BitcoinNet using ParamsForNet, but be aware that this usage is deprecated and will be removed from chaincfg in the future.

For main packages, a (typically global) var may be assigned the address of one of the standard Param vars for use as the application's "active" network. When a network parameter is needed, it may then be looked up through this variable (either directly, or hidden in a library call).

package main

import (
        "flag"
        "fmt"
        "log"

        "github.com/CryptocurrencyCabal/btcutil"
        "github.com/CryptocurrencyCabal/htcd/chaincfg"
)

var testnet = flag.Bool("testnet", false, "operate on the testnet Bitcoin network")

// By default (without -testnet), use mainnet.
var chainParams = &chaincfg.MainNetParams

func main() {
        flag.Parse()

        // Modify active network parameters if operating on testnet.
        if *testnet {
                chainParams = &chaincfg.TestNet3Params
        }

        // later...

        // Create and print new payment address, specific to the active network.
        pubKeyHash := make([]byte, 20)
        addr, err := btcutil.NewAddressPubKeyHash(pubKeyHash, chainParams)
        if err != nil {
                log.Fatal(err)
        }
        fmt.Println(addr)
}

If an application does not use one of the three standard Bitcoin networks, a new Params struct may be created which defines the parameters for the non-standard network. As a general rule of thumb, all network parameters should be unique to the network, but parameter collisions can still occur (unfortunately, this is the case with regtest and testnet3 sharing magics).

Index

• Variables
• func HDPrivateKeyToPublicKeyID(id []byte) ([]byte, error)
• func IsPubKeyHashAddrID(id byte) bool
• func IsScriptHashAddrID(id byte) bool
• func Register(params *Params) error
• type Checkpoint
• type Params

Variables

var (
	// ErrDuplicateNet describes an error where the parameters for a Bitcoin
	// network could not be set due to the network already being a standard
	// network or previously-registered into this package.
	ErrDuplicateNet = errors.New("duplicate Bitcoin network")

	// ErrUnknownHDKeyID describes an error where the provided id which
	// is intended to identify the network for a hierarchical deterministic
	// private extended key is not registered.
	ErrUnknownHDKeyID = errors.New("unknown hd private extended key bytes")
)

var HooNetParams = Params{
	Name:        "hoonet",
	Net:         wire.HooNet,
	DefaultPort: "8333",

	GenesisBlock:           &genesisBlock,
	GenesisHash:            &genesisHash,
	PowLimit:               mainPowLimit,
	PowLimitBits:           0x1d00ffff,
	SubsidyHalvingInterval: 210000,
	ResetMinDifficulty:     false,
	GenerateSupported:      false,

	Checkpoints: []Checkpoint{},

	BlockEnforceNumRequired: 750,
	BlockRejectNumRequired:  950,
	BlockUpgradeNumToCheck:  1000,

	RelayNonStdTxs: false,

	PubKeyHashAddrID: 0x00,
	ScriptHashAddrID: 0x05,
	PrivateKeyID:     0x80,

	HDPrivateKeyID: [4]byte{0x04, 0x88, 0xad, 0xe4},
	HDPublicKeyID:  [4]byte{0x04, 0x88, 0xb2, 0x1e},

	HDCoinType: 0,
}

HooNetParams defines the network parameters for the HooCoin network.

var MainNetParams = Params{
	Name:        "mainnet",
	Net:         wire.MainNet,
	DefaultPort: "8333",

	GenesisBlock:           &genesisBlock,
	GenesisHash:            &genesisHash,
	PowLimit:               mainPowLimit,
	PowLimitBits:           0x1d00ffff,
	SubsidyHalvingInterval: 210000,
	ResetMinDifficulty:     false,
	GenerateSupported:      false,

	Checkpoints: []Checkpoint{
		{11111, newShaHashFromStr("0000000069e244f73d78e8fd29ba2fd2ed618bd6fa2ee92559f542fdb26e7c1d")},
		{33333, newShaHashFromStr("000000002dd5588a74784eaa7ab0507a18ad16a236e7b1ce69f00d7ddfb5d0a6")},
		{74000, newShaHashFromStr("0000000000573993a3c9e41ce34471c079dcf5f52a0e824a81e7f953b8661a20")},
		{105000, newShaHashFromStr("00000000000291ce28027faea320c8d2b054b2e0fe44a773f3eefb151d6bdc97")},
		{134444, newShaHashFromStr("00000000000005b12ffd4cd315cd34ffd4a594f430ac814c91184a0d42d2b0fe")},
		{168000, newShaHashFromStr("000000000000099e61ea72015e79632f216fe6cb33d7899acb35b75c8303b763")},
		{193000, newShaHashFromStr("000000000000059f452a5f7340de6682a977387c17010ff6e6c3bd83ca8b1317")},
		{210000, newShaHashFromStr("000000000000048b95347e83192f69cf0366076336c639f9b7228e9ba171342e")},
		{216116, newShaHashFromStr("00000000000001b4f4b433e81ee46494af945cf96014816a4e2370f11b23df4e")},
		{225430, newShaHashFromStr("00000000000001c108384350f74090433e7fcf79a606b8e797f065b130575932")},
		{250000, newShaHashFromStr("000000000000003887df1f29024b06fc2200b55f8af8f35453d7be294df2d214")},
		{267300, newShaHashFromStr("000000000000000a83fbd660e918f218bf37edd92b748ad940483c7c116179ac")},
		{279000, newShaHashFromStr("0000000000000001ae8c72a0b0c301f67e3afca10e819efa9041e458e9bd7e40")},
		{300255, newShaHashFromStr("0000000000000000162804527c6e9b9f0563a280525f9d08c12041def0a0f3b2")},
		{319400, newShaHashFromStr("000000000000000021c6052e9becade189495d1c539aa37c58917305fd15f13b")},
		{343185, newShaHashFromStr("0000000000000000072b8bf361d01a6ba7d445dd024203fafc78768ed4368554")},
		{352940, newShaHashFromStr("000000000000000010755df42dba556bb72be6a32f3ce0b6941ce4430152c9ff")},
	},

	BlockEnforceNumRequired: 750,
	BlockRejectNumRequired:  950,
	BlockUpgradeNumToCheck:  1000,

	RelayNonStdTxs: false,

	PubKeyHashAddrID: 0x00,
	ScriptHashAddrID: 0x05,
	PrivateKeyID:     0x80,

	HDPrivateKeyID: [4]byte{0x04, 0x88, 0xad, 0xe4},
	HDPublicKeyID:  [4]byte{0x04, 0x88, 0xb2, 0x1e},

	HDCoinType: 0,
}

MainNetParams defines the network parameters for the main Bitcoin network.

var RegressionNetParams = Params{
	Name:        "regtest",
	Net:         wire.TestNet,
	DefaultPort: "18444",

	GenesisBlock:           &regTestGenesisBlock,
	GenesisHash:            &regTestGenesisHash,
	PowLimit:               regressionPowLimit,
	PowLimitBits:           0x207fffff,
	SubsidyHalvingInterval: 150,
	ResetMinDifficulty:     true,
	GenerateSupported:      true,

	Checkpoints: nil,

	BlockEnforceNumRequired: 750,
	BlockRejectNumRequired:  950,
	BlockUpgradeNumToCheck:  1000,

	RelayNonStdTxs: true,

	PubKeyHashAddrID: 0x6f,
	ScriptHashAddrID: 0xc4,
	PrivateKeyID:     0xef,

	HDPrivateKeyID: [4]byte{0x04, 0x35, 0x83, 0x94},
	HDPublicKeyID:  [4]byte{0x04, 0x35, 0x87, 0xcf},

	HDCoinType: 1,
}

RegressionNetParams defines the network parameters for the regression test Bitcoin network. Not to be confused with the test Bitcoin network (version 3), this network is sometimes simply called "testnet".

var SimNetParams = Params{
	Name:        "simnet",
	Net:         wire.SimNet,
	DefaultPort: "18555",

	GenesisBlock:           &simNetGenesisBlock,
	GenesisHash:            &simNetGenesisHash,
	PowLimit:               simNetPowLimit,
	PowLimitBits:           0x207fffff,
	SubsidyHalvingInterval: 210000,
	ResetMinDifficulty:     true,
	GenerateSupported:      true,

	Checkpoints: nil,

	BlockEnforceNumRequired: 51,
	BlockRejectNumRequired:  75,
	BlockUpgradeNumToCheck:  100,

	RelayNonStdTxs: true,

	PubKeyHashAddrID: 0x3f,
	ScriptHashAddrID: 0x7b,
	PrivateKeyID:     0x64,

	HDPrivateKeyID: [4]byte{0x04, 0x20, 0xb9, 0x00},
	HDPublicKeyID:  [4]byte{0x04, 0x20, 0xbd, 0x3a},

	HDCoinType: 115,
}

SimNetParams defines the network parameters for the simulation test Bitcoin network. This network is similar to the normal test network except it is intended for private use within a group of individuals doing simulation testing. The functionality is intended to differ in that the only nodes which are specifically specified are used to create the network rather than following normal discovery rules. This is important as otherwise it would just turn into another public testnet.

var TestNet3Params = Params{
	Name:        "testnet3",
	Net:         wire.TestNet3,
	DefaultPort: "18333",

	GenesisBlock:           &testNet3GenesisBlock,
	GenesisHash:            &testNet3GenesisHash,
	PowLimit:               testNet3PowLimit,
	PowLimitBits:           0x1d00ffff,
	SubsidyHalvingInterval: 210000,
	ResetMinDifficulty:     true,
	GenerateSupported:      false,

	Checkpoints: []Checkpoint{
		{546, newShaHashFromStr("000000002a936ca763904c3c35fce2f3556c559c0214345d31b1bcebf76acb70")},
	},

	BlockEnforceNumRequired: 51,
	BlockRejectNumRequired:  75,
	BlockUpgradeNumToCheck:  100,

	RelayNonStdTxs: true,

	PubKeyHashAddrID: 0x6f,
	ScriptHashAddrID: 0xc4,
	PrivateKeyID:     0xef,

	HDPrivateKeyID: [4]byte{0x04, 0x35, 0x83, 0x94},
	HDPublicKeyID:  [4]byte{0x04, 0x35, 0x87, 0xcf},

	HDCoinType: 1,
}

TestNet3Params defines the network parameters for the test Bitcoin network (version 3). Not to be confused with the regression test network, this network is sometimes simply called "testnet".

Functions

func HDPrivateKeyToPublicKeyID

func HDPrivateKeyToPublicKeyID(id []byte) ([]byte, error)

HDPrivateKeyToPublicKeyID accepts a private hierarchical deterministic extended key id and returns the associated public key id. When the provided id is not registered, the ErrUnknownHDKeyID error will be returned.

func IsPubKeyHashAddrID

func IsPubKeyHashAddrID(id byte) bool

IsPubKeyHashAddrID returns whether the id is an identifier known to prefix a pay-to-pubkey-hash address on any default or registered network. This is used when decoding an address string into a specific address type. It is up to the caller to check both this and IsScriptHashAddrID and decide whether an address is a pubkey hash address, script hash address, neither, or undeterminable (if both return true).

func IsScriptHashAddrID

func IsScriptHashAddrID(id byte) bool

IsScriptHashAddrID returns whether the id is an identifier known to prefix a pay-to-script-hash address on any default or registered network. This is used when decoding an address string into a specific address type. It is up to the caller to check both this and IsPubKeyHashAddrID and decide whether an address is a pubkey hash address, script hash address, neither, or undeterminable (if both return true).

func Register

func Register(params *Params) error

Register registers the network parameters for a Bitcoin network. This may error with ErrDuplicateNet if the network is already registered (either due to a previous Register call, or the network being one of the default networks).

Network parameters should be registered into this package by a main package as early as possible. Then, library packages may lookup networks or network parameters based on inputs and work regardless of the network being standard or not.

Types

type Checkpoint

type Checkpoint struct {
	Height int32
	Hash   *wire.ShaHash
}

Checkpoint identifies a known good point in the block chain. Using checkpoints allows a few optimizations for old blocks during initial download and also prevents forks from old blocks.

Each checkpoint is selected based upon several factors. See the documentation for blockchain.IsCheckpointCandidate for details on the selection criteria.

type Params

type Params struct {
	Name        string
	Net         wire.BitcoinNet
	DefaultPort string

	// Chain parameters
	GenesisBlock           *wire.MsgBlock
	GenesisHash            *wire.ShaHash
	PowLimit               *big.Int
	PowLimitBits           uint32
	SubsidyHalvingInterval int32
	ResetMinDifficulty     bool
	GenerateSupported      bool

	// Checkpoints ordered from oldest to newest.
	Checkpoints []Checkpoint

	// Enforce current block version once network has
	// upgraded.  This is part of BIP0034.
	BlockEnforceNumRequired uint64

	// Reject previous block versions once network has
	// upgraded.  This is part of BIP0034.
	BlockRejectNumRequired uint64

	// The number of nodes to check.  This is part of BIP0034.
	BlockUpgradeNumToCheck uint64

	// Mempool parameters
	RelayNonStdTxs bool

	// Address encoding magics
	PubKeyHashAddrID byte // First byte of a P2PKH address
	ScriptHashAddrID byte // First byte of a P2SH address
	PrivateKeyID     byte // First byte of a WIF private key

	// BIP32 hierarchical deterministic extended key magics
	HDPrivateKeyID [4]byte
	HDPublicKeyID  [4]byte

	// BIP44 coin type used in the hierarchical deterministic path for
	// address generation.
	HDCoinType uint32
}

Params defines a Bitcoin network by its parameters. These parameters may be used by Bitcoin applications to differentiate networks as well as addresses and keys for one network from those intended for use on another network.