Example #1
0
// This example demonstrates creating a script which pays to a bitcoin address.
// It also prints the created script hex and uses the DisasmString function to
// display the disassembled script.
func ExamplePayToAddrScript() {
	// Parse the address to send the coins to into a btcutil.Address
	// which is useful to ensure the accuracy of the address and determine
	// the address type.  It is also required for the upcoming call to
	// PayToAddrScript.
	addressStr := "12gpXQVcCL2qhTNQgyLVdCFG2Qs2px98nV"
	address, err := btcutil.DecodeAddress(addressStr, &chaincfg.MainNetParams)
	if err != nil {
		fmt.Println(err)
		return
	}

	// Create a public key script that pays to the address.
	script, err := txscript.PayToAddrScript(address)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Printf("Script Hex: %x\n", script)

	disasm, err := txscript.DisasmString(script)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Println("Script Disassembly:", disasm)

	// Output:
	// Script Hex: 76a914128004ff2fcaf13b2b91eb654b1dc2b674f7ec6188ac
	// Script Disassembly: OP_DUP OP_HASH160 128004ff2fcaf13b2b91eb654b1dc2b674f7ec61 OP_EQUALVERIFY OP_CHECKSIG
}
Example #2
0
func TestLimitAndSkipFetchTxsForAddr(t *testing.T) {
	testDb, err := setUpTestDb(t, "tstdbtxaddr")
	if err != nil {
		t.Errorf("Failed to open test database %v", err)
		return
	}
	defer testDb.cleanUpFunc()

	// Insert a block with some fake test transactions. The block will have
	// 10 copies of a fake transaction involving same address.
	addrString := "1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa"
	targetAddr, err := btcutil.DecodeAddress(addrString, &chaincfg.MainNetParams)
	if err != nil {
		t.Fatalf("Unable to decode test address: %v", err)
	}
	outputScript, err := txscript.PayToAddrScript(targetAddr)
	if err != nil {
		t.Fatalf("Unable make test pkScript %v", err)
	}
	fakeTxOut := wire.NewTxOut(10, outputScript)
	var emptyHash wire.ShaHash
	fakeHeader := wire.NewBlockHeader(&emptyHash, &emptyHash, 1, 1)
	msgBlock := wire.NewMsgBlock(fakeHeader)
	for i := 0; i < 10; i++ {
		mtx := wire.NewMsgTx()
		mtx.AddTxOut(fakeTxOut)
		msgBlock.AddTransaction(mtx)
	}

	// Insert the test block into the DB.
	testBlock := btcutil.NewBlock(msgBlock)
	newheight, err := testDb.db.InsertBlock(testBlock)
	if err != nil {
		t.Fatalf("Unable to insert block into db: %v", err)
	}

	// Create and insert an address index for out test addr.
	txLoc, _ := testBlock.TxLoc()
	index := make(database.BlockAddrIndex)
	for i := range testBlock.Transactions() {
		var hash160 [ripemd160.Size]byte
		scriptAddr := targetAddr.ScriptAddress()
		copy(hash160[:], scriptAddr[:])
		index[hash160] = append(index[hash160], &txLoc[i])
	}
	blkSha := testBlock.Sha()
	err = testDb.db.UpdateAddrIndexForBlock(blkSha, newheight, index)
	if err != nil {
		t.Fatalf("UpdateAddrIndexForBlock: failed to index"+
			" addrs for block #%d (%s) "+
			"err %v", newheight, blkSha, err)
		return
	}

	// Try skipping the first 4 results, should get 6 in return.
	txReply, txSkipped, err := testDb.db.FetchTxsForAddr(targetAddr, 4, 100000, false)
	if err != nil {
		t.Fatalf("Unable to fetch transactions for address: %v", err)
	}
	if txSkipped != 4 {
		t.Fatalf("Did not correctly return skipped amount"+
			" got %v txs, expected %v", txSkipped, 4)
	}
	if len(txReply) != 6 {
		t.Fatalf("Did not correctly skip forward in txs for address reply"+
			" got %v txs, expected %v", len(txReply), 6)
	}

	// Limit the number of results to 3.
	txReply, txSkipped, err = testDb.db.FetchTxsForAddr(targetAddr, 0, 3, false)
	if err != nil {
		t.Fatalf("Unable to fetch transactions for address: %v", err)
	}
	if txSkipped != 0 {
		t.Fatalf("Did not correctly return skipped amount"+
			" got %v txs, expected %v", txSkipped, 0)
	}
	if len(txReply) != 3 {
		t.Fatalf("Did not correctly limit in txs for address reply"+
			" got %v txs, expected %v", len(txReply), 3)
	}

	// Skip 1, limit 5.
	txReply, txSkipped, err = testDb.db.FetchTxsForAddr(targetAddr, 1, 5, false)
	if err != nil {
		t.Fatalf("Unable to fetch transactions for address: %v", err)
	}
	if txSkipped != 1 {
		t.Fatalf("Did not correctly return skipped amount"+
			" got %v txs, expected %v", txSkipped, 1)
	}
	if len(txReply) != 5 {
		t.Fatalf("Did not correctly limit in txs for address reply"+
			" got %v txs, expected %v", len(txReply), 5)
	}
}
Example #3
0
// loadConfig initializes and parses the config using a config file and command
// line options.
//
// The configuration proceeds as follows:
// 	1) Start with a default config with sane settings
// 	2) Pre-parse the command line to check for an alternative config file
// 	3) Load configuration file overwriting defaults with any specified options
// 	4) Parse CLI options and overwrite/add any specified options
//
// The above results in btcd functioning properly without any config settings
// while still allowing the user to override settings with config files and
// command line options.  Command line options always take precedence.
func loadConfig() (*config, []string, error) {
	// Default config.
	cfg := config{
		ConfigFile:        defaultConfigFile,
		DebugLevel:        defaultLogLevel,
		MaxPeers:          defaultMaxPeers,
		BanDuration:       defaultBanDuration,
		RPCMaxClients:     defaultMaxRPCClients,
		RPCMaxWebsockets:  defaultMaxRPCWebsockets,
		DataDir:           defaultDataDir,
		LogDir:            defaultLogDir,
		DbType:            defaultDbType,
		RPCKey:            defaultRPCKeyFile,
		RPCCert:           defaultRPCCertFile,
		MinRelayTxFee:     defaultMinRelayTxFee.ToBTC(),
		FreeTxRelayLimit:  defaultFreeTxRelayLimit,
		BlockMinSize:      defaultBlockMinSize,
		BlockMaxSize:      defaultBlockMaxSize,
		BlockPrioritySize: defaultBlockPrioritySize,
		SigCacheMaxSize:   defaultSigCacheMaxSize,
		MaxOrphanTxs:      maxOrphanTransactions,
		Generate:          defaultGenerate,
		AddrIndex:         defaultAddrIndex,
	}

	// Service options which are only added on Windows.
	serviceOpts := serviceOptions{}

	// Pre-parse the command line options to see if an alternative config
	// file or the version flag was specified.  Any errors aside from the
	// help message error can be ignored here since they will be caught by
	// the final parse below.
	preCfg := cfg
	preParser := newConfigParser(&preCfg, &serviceOpts, flags.HelpFlag)
	_, err := preParser.Parse()
	if err != nil {
		if e, ok := err.(*flags.Error); ok && e.Type == flags.ErrHelp {
			fmt.Fprintln(os.Stderr, err)
			return nil, nil, err
		}
	}

	// Show the version and exit if the version flag was specified.
	appName := filepath.Base(os.Args[0])
	appName = strings.TrimSuffix(appName, filepath.Ext(appName))
	usageMessage := fmt.Sprintf("Use %s -h to show usage", appName)
	if preCfg.ShowVersion {
		fmt.Println(appName, "version", version())
		os.Exit(0)
	}

	// Perform service command and exit if specified.  Invalid service
	// commands show an appropriate error.  Only runs on Windows since
	// the runServiceCommand function will be nil when not on Windows.
	if serviceOpts.ServiceCommand != "" && runServiceCommand != nil {
		err := runServiceCommand(serviceOpts.ServiceCommand)
		if err != nil {
			fmt.Fprintln(os.Stderr, err)
		}
		os.Exit(0)
	}

	// Load additional config from file.
	var configFileError error
	parser := newConfigParser(&cfg, &serviceOpts, flags.Default)
	if !(preCfg.RegressionTest || preCfg.SimNet) || preCfg.ConfigFile !=
		defaultConfigFile {

		err := flags.NewIniParser(parser).ParseFile(preCfg.ConfigFile)
		if err != nil {
			if _, ok := err.(*os.PathError); !ok {
				fmt.Fprintf(os.Stderr, "Error parsing config "+
					"file: %v\n", err)
				fmt.Fprintln(os.Stderr, usageMessage)
				return nil, nil, err
			}
			configFileError = err
		}
	}

	// Don't add peers from the config file when in regression test mode.
	if preCfg.RegressionTest && len(cfg.AddPeers) > 0 {
		cfg.AddPeers = nil
	}

	// Parse command line options again to ensure they take precedence.
	remainingArgs, err := parser.Parse()
	if err != nil {
		if e, ok := err.(*flags.Error); !ok || e.Type != flags.ErrHelp {
			fmt.Fprintln(os.Stderr, usageMessage)
		}
		return nil, nil, err
	}

	// Create the home directory if it doesn't already exist.
	funcName := "loadConfig"
	err = os.MkdirAll(btcdHomeDir, 0700)
	if err != nil {
		// Show a nicer error message if it's because a symlink is
		// linked to a directory that does not exist (probably because
		// it's not mounted).
		if e, ok := err.(*os.PathError); ok && os.IsExist(err) {
			if link, lerr := os.Readlink(e.Path); lerr == nil {
				str := "is symlink %s -> %s mounted?"
				err = fmt.Errorf(str, e.Path, link)
			}
		}

		str := "%s: Failed to create home directory: %v"
		err := fmt.Errorf(str, funcName, err)
		fmt.Fprintln(os.Stderr, err)
		return nil, nil, err
	}

	// Multiple networks can't be selected simultaneously.
	numNets := 0
	// Count number of network flags passed; assign active network params
	// while we're at it
	if cfg.TestNet3 {
		numNets++
		activeNetParams = &testNet3Params
	}
	if cfg.RegressionTest {
		numNets++
		activeNetParams = &regressionNetParams
	}
	if cfg.SimNet {
		numNets++
		// Also disable dns seeding on the simulation test network.
		activeNetParams = &simNetParams
		cfg.DisableDNSSeed = true
	}
	if numNets > 1 {
		str := "%s: The testnet, regtest, and simnet params can't be " +
			"used together -- choose one of the three"
		err := fmt.Errorf(str, funcName)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Append the network type to the data directory so it is "namespaced"
	// per network.  In addition to the block database, there are other
	// pieces of data that are saved to disk such as address manager state.
	// All data is specific to a network, so namespacing the data directory
	// means each individual piece of serialized data does not have to
	// worry about changing names per network and such.
	cfg.DataDir = cleanAndExpandPath(cfg.DataDir)
	cfg.DataDir = filepath.Join(cfg.DataDir, netName(activeNetParams))

	// Append the network type to the log directory so it is "namespaced"
	// per network in the same fashion as the data directory.
	cfg.LogDir = cleanAndExpandPath(cfg.LogDir)
	cfg.LogDir = filepath.Join(cfg.LogDir, netName(activeNetParams))

	// Special show command to list supported subsystems and exit.
	if cfg.DebugLevel == "show" {
		fmt.Println("Supported subsystems", supportedSubsystems())
		os.Exit(0)
	}

	// Initialize logging at the default logging level.
	initSeelogLogger(filepath.Join(cfg.LogDir, defaultLogFilename))
	setLogLevels(defaultLogLevel)

	// Parse, validate, and set debug log level(s).
	if err := parseAndSetDebugLevels(cfg.DebugLevel); err != nil {
		err := fmt.Errorf("%s: %v", funcName, err.Error())
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Validate database type.
	if !validDbType(cfg.DbType) {
		str := "%s: The specified database type [%v] is invalid -- " +
			"supported types %v"
		err := fmt.Errorf(str, funcName, cfg.DbType, knownDbTypes)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	if cfg.AddrIndex && cfg.DropAddrIndex {
		err := fmt.Errorf("addrindex and dropaddrindex cannot be " +
			"activated at the same")
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Memdb does not currently support the addrindex.
	if cfg.DbType == "memdb" && cfg.AddrIndex {
		err := fmt.Errorf("memdb does not currently support the addrindex")
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Validate profile port number
	if cfg.Profile != "" {
		profilePort, err := strconv.Atoi(cfg.Profile)
		if err != nil || profilePort < 1024 || profilePort > 65535 {
			str := "%s: The profile port must be between 1024 and 65535"
			err := fmt.Errorf(str, funcName)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}
	}

	// Don't allow ban durations that are too short.
	if cfg.BanDuration < time.Duration(time.Second) {
		str := "%s: The banduration option may not be less than 1s -- parsed [%v]"
		err := fmt.Errorf(str, funcName, cfg.BanDuration)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// --addPeer and --connect do not mix.
	if len(cfg.AddPeers) > 0 && len(cfg.ConnectPeers) > 0 {
		str := "%s: the --addpeer and --connect options can not be " +
			"mixed"
		err := fmt.Errorf(str, funcName)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// --proxy or --connect without --listen disables listening.
	if (cfg.Proxy != "" || len(cfg.ConnectPeers) > 0) &&
		len(cfg.Listeners) == 0 {
		cfg.DisableListen = true
	}

	// Connect means no DNS seeding.
	if len(cfg.ConnectPeers) > 0 {
		cfg.DisableDNSSeed = true
	}

	// Add the default listener if none were specified. The default
	// listener is all addresses on the listen port for the network
	// we are to connect to.
	if len(cfg.Listeners) == 0 {
		cfg.Listeners = []string{
			net.JoinHostPort("", activeNetParams.DefaultPort),
		}
	}

	// Check to make sure limited and admin users don't have the same username
	if cfg.RPCUser == cfg.RPCLimitUser && cfg.RPCUser != "" {
		str := "%s: --rpcuser and --rpclimituser must not specify the " +
			"same username"
		err := fmt.Errorf(str, funcName)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Check to make sure limited and admin users don't have the same password
	if cfg.RPCPass == cfg.RPCLimitPass && cfg.RPCPass != "" {
		str := "%s: --rpcpass and --rpclimitpass must not specify the " +
			"same password"
		err := fmt.Errorf(str, funcName)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// The RPC server is disabled if no username or password is provided.
	if (cfg.RPCUser == "" || cfg.RPCPass == "") &&
		(cfg.RPCLimitUser == "" || cfg.RPCLimitPass == "") {
		cfg.DisableRPC = true
	}

	// Default RPC to listen on localhost only.
	if !cfg.DisableRPC && len(cfg.RPCListeners) == 0 {
		addrs, err := net.LookupHost("localhost")
		if err != nil {
			return nil, nil, err
		}
		cfg.RPCListeners = make([]string, 0, len(addrs))
		for _, addr := range addrs {
			addr = net.JoinHostPort(addr, activeNetParams.rpcPort)
			cfg.RPCListeners = append(cfg.RPCListeners, addr)
		}
	}

	// Validate the the minrelaytxfee.
	cfg.minRelayTxFee, err = btcutil.NewAmount(cfg.MinRelayTxFee)
	if err != nil {
		str := "%s: invalid minrelaytxfee: %v"
		err := fmt.Errorf(str, funcName, err)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Limit the max block size to a sane value.
	if cfg.BlockMaxSize < blockMaxSizeMin || cfg.BlockMaxSize >
		blockMaxSizeMax {

		str := "%s: The blockmaxsize option must be in between %d " +
			"and %d -- parsed [%d]"
		err := fmt.Errorf(str, funcName, blockMaxSizeMin,
			blockMaxSizeMax, cfg.BlockMaxSize)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Limit the max orphan count to a sane vlue.
	if cfg.MaxOrphanTxs < 0 {
		str := "%s: The maxorphantx option may not be less than 0 " +
			"-- parsed [%d]"
		err := fmt.Errorf(str, funcName, cfg.MaxOrphanTxs)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Limit the block priority and minimum block sizes to max block size.
	cfg.BlockPrioritySize = minUint32(cfg.BlockPrioritySize, cfg.BlockMaxSize)
	cfg.BlockMinSize = minUint32(cfg.BlockMinSize, cfg.BlockMaxSize)

	// Check getwork keys are valid and saved parsed versions.
	cfg.miningAddrs = make([]btcutil.Address, 0, len(cfg.GetWorkKeys)+
		len(cfg.MiningAddrs))
	for _, strAddr := range cfg.GetWorkKeys {
		addr, err := btcutil.DecodeAddress(strAddr,
			activeNetParams.Params)
		if err != nil {
			str := "%s: getworkkey '%s' failed to decode: %v"
			err := fmt.Errorf(str, funcName, strAddr, err)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}
		if !addr.IsForNet(activeNetParams.Params) {
			str := "%s: getworkkey '%s' is on the wrong network"
			err := fmt.Errorf(str, funcName, strAddr)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}
		cfg.miningAddrs = append(cfg.miningAddrs, addr)
	}

	// Check mining addresses are valid and saved parsed versions.
	for _, strAddr := range cfg.MiningAddrs {
		addr, err := btcutil.DecodeAddress(strAddr, activeNetParams.Params)
		if err != nil {
			str := "%s: mining address '%s' failed to decode: %v"
			err := fmt.Errorf(str, funcName, strAddr, err)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}
		if !addr.IsForNet(activeNetParams.Params) {
			str := "%s: mining address '%s' is on the wrong network"
			err := fmt.Errorf(str, funcName, strAddr)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}
		cfg.miningAddrs = append(cfg.miningAddrs, addr)
	}

	// Ensure there is at least one mining address when the generate flag is
	// set.
	if cfg.Generate && len(cfg.MiningAddrs) == 0 {
		str := "%s: the generate flag is set, but there are no mining " +
			"addresses specified "
		err := fmt.Errorf(str, funcName)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Add default port to all listener addresses if needed and remove
	// duplicate addresses.
	cfg.Listeners = normalizeAddresses(cfg.Listeners,
		activeNetParams.DefaultPort)

	// Add default port to all rpc listener addresses if needed and remove
	// duplicate addresses.
	cfg.RPCListeners = normalizeAddresses(cfg.RPCListeners,
		activeNetParams.rpcPort)

	// Only allow TLS to be disabled if the RPC is bound to localhost
	// addresses.
	if !cfg.DisableRPC && cfg.DisableTLS {
		allowedTLSListeners := map[string]struct{}{
			"localhost": struct{}{},
			"127.0.0.1": struct{}{},
			"::1":       struct{}{},
		}
		for _, addr := range cfg.RPCListeners {
			host, _, err := net.SplitHostPort(addr)
			if err != nil {
				str := "%s: RPC listen interface '%s' is " +
					"invalid: %v"
				err := fmt.Errorf(str, funcName, addr, err)
				fmt.Fprintln(os.Stderr, err)
				fmt.Fprintln(os.Stderr, usageMessage)
				return nil, nil, err
			}
			if _, ok := allowedTLSListeners[host]; !ok {
				str := "%s: the --notls option may not be used " +
					"when binding RPC to non localhost " +
					"addresses: %s"
				err := fmt.Errorf(str, funcName, addr)
				fmt.Fprintln(os.Stderr, err)
				fmt.Fprintln(os.Stderr, usageMessage)
				return nil, nil, err
			}
		}
	}

	// Add default port to all added peer addresses if needed and remove
	// duplicate addresses.
	cfg.AddPeers = normalizeAddresses(cfg.AddPeers,
		activeNetParams.DefaultPort)
	cfg.ConnectPeers = normalizeAddresses(cfg.ConnectPeers,
		activeNetParams.DefaultPort)

	// Tor stream isolation requires either proxy or onion proxy to be set.
	if cfg.TorIsolation && cfg.Proxy == "" && cfg.OnionProxy == "" {
		str := "%s: Tor stream isolation requires either proxy or " +
			"onionproxy to be set"
		err := fmt.Errorf(str, funcName)
		fmt.Fprintln(os.Stderr, err)
		fmt.Fprintln(os.Stderr, usageMessage)
		return nil, nil, err
	}

	// Setup dial and DNS resolution (lookup) functions depending on the
	// specified options.  The default is to use the standard net.Dial
	// function as well as the system DNS resolver.  When a proxy is
	// specified, the dial function is set to the proxy specific dial
	// function and the lookup is set to use tor (unless --noonion is
	// specified in which case the system DNS resolver is used).
	cfg.dial = net.Dial
	cfg.lookup = net.LookupIP
	if cfg.Proxy != "" {
		_, _, err := net.SplitHostPort(cfg.Proxy)
		if err != nil {
			str := "%s: Proxy address '%s' is invalid: %v"
			err := fmt.Errorf(str, funcName, cfg.Proxy, err)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}

		if cfg.TorIsolation &&
			(cfg.ProxyUser != "" || cfg.ProxyPass != "") {
			btcdLog.Warn("Tor isolation set -- overriding " +
				"specified proxy user credentials")
		}

		proxy := &socks.Proxy{
			Addr:         cfg.Proxy,
			Username:     cfg.ProxyUser,
			Password:     cfg.ProxyPass,
			TorIsolation: cfg.TorIsolation,
		}
		cfg.dial = proxy.Dial
		if !cfg.NoOnion {
			cfg.lookup = func(host string) ([]net.IP, error) {
				return torLookupIP(host, cfg.Proxy)
			}
		}
	}

	// Setup onion address dial and DNS resolution (lookup) functions
	// depending on the specified options.  The default is to use the
	// same dial and lookup functions selected above.  However, when an
	// onion-specific proxy is specified, the onion address dial and
	// lookup functions are set to use the onion-specific proxy while
	// leaving the normal dial and lookup functions as selected above.
	// This allows .onion address traffic to be routed through a different
	// proxy than normal traffic.
	if cfg.OnionProxy != "" {
		_, _, err := net.SplitHostPort(cfg.OnionProxy)
		if err != nil {
			str := "%s: Onion proxy address '%s' is invalid: %v"
			err := fmt.Errorf(str, funcName, cfg.OnionProxy, err)
			fmt.Fprintln(os.Stderr, err)
			fmt.Fprintln(os.Stderr, usageMessage)
			return nil, nil, err
		}

		if cfg.TorIsolation &&
			(cfg.OnionProxyUser != "" || cfg.OnionProxyPass != "") {
			btcdLog.Warn("Tor isolation set -- overriding " +
				"specified onionproxy user credentials ")
		}

		cfg.oniondial = func(a, b string) (net.Conn, error) {
			proxy := &socks.Proxy{
				Addr:         cfg.OnionProxy,
				Username:     cfg.OnionProxyUser,
				Password:     cfg.OnionProxyPass,
				TorIsolation: cfg.TorIsolation,
			}
			return proxy.Dial(a, b)
		}
		cfg.onionlookup = func(host string) ([]net.IP, error) {
			return torLookupIP(host, cfg.OnionProxy)
		}
	} else {
		cfg.oniondial = cfg.dial
		cfg.onionlookup = cfg.lookup
	}

	// Specifying --noonion means the onion address dial and DNS resolution
	// (lookup) functions result in an error.
	if cfg.NoOnion {
		cfg.oniondial = func(a, b string) (net.Conn, error) {
			return nil, errors.New("tor has been disabled")
		}
		cfg.onionlookup = func(a string) ([]net.IP, error) {
			return nil, errors.New("tor has been disabled")
		}
	}

	// Warn about missing config file only after all other configuration is
	// done.  This prevents the warning on help messages and invalid
	// options.  Note this should go directly before the return.
	if configFileError != nil {
		btcdLog.Warnf("%v", configFileError)
	}

	return &cfg, remainingArgs, nil
}