Initial commit.

Godeps/Godeps.json

@@ -0,0 +1,12 @@
+{
+	"ImportPath": "git.crumpington.com/public/ttunnel",
+	"GoVersion": "go1.9",
+	"GodepVersion": "v79",
+	"Deps": [
+		{
+			"ImportPath": "github.com/BurntSushi/toml",
+			"Comment": "v0.2.0-21-g9906417",
+			"Rev": "99064174e013895bbd9b025c31100bd1d9b590ca"
+		}
+	]
+}

Godeps/Readme

@@ -0,0 +1,5 @@
+This directory tree is generated automatically by godep.
+
+Please do not edit.
+
+See https://github.com/tools/godep for more information.

bin/ttunnel.go

@@ -0,0 +1,7 @@
+package main
+
+import "git.crumpington.com/public/ttunnel"
+
+func main() {
+	ttunnel.Main()
+}

client.go

@@ -0,0 +1,88 @@
+package ttunnel
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"io"
+	"log"
+	"net"
+	"strings"
+
+	"github.com/BurntSushi/toml"
+)
+
+type ClientConfig struct {
+	Listen   string
+	Server   string // Must be IP:port.
+	Password string
+	password []byte
+}
+
+func (cc ClientConfig) ServerIP() string {
+	return strings.Split(cc.Server, ":")[0]
+}
+
+// RunClient runs a client using the named configuration.
+func RunClient(path string) {
+	conf := ClientConfig{}
+	if _, err := toml.DecodeFile(path, &conf); err != nil {
+		log.Printf("Failed to load config file %s: %v", path, err)
+		return
+	}
+	conf.password = []byte(conf.Password)
+
+	_, certBuf := genCerts(conf.password, conf.ServerIP())
+
+	// Create a certificate pool for the client.
+	certPool := x509.NewCertPool()
+	if !certPool.AppendCertsFromPEM(certBuf) {
+		log.Printf("Failed to append certificate to pool.")
+		return
+	}
+
+	// Create the client configuration.
+	config := tls.Config{RootCAs: certPool}
+
+	// Accept connections on the local port.
+	ln, err := net.Listen("tcp", conf.Listen)
+	if err != nil {
+		log.Printf("Failed to listen on %s: %v", conf.Listen, err)
+		return
+	}
+
+	// Accept connections forever.
+	for {
+		lConn, err := ln.Accept()
+		if err != nil {
+			log.Printf("Failed to accept connection: %v", err)
+			continue
+		}
+		go clientHandler(conf, lConn, &config)
+	}
+}
+
+func clientHandler(conf ClientConfig, lConn net.Conn, config *tls.Config) {
+	// Dial remote server.
+	rConn, err := tls.Dial("tcp", conf.Server, config)
+	if err != nil {
+		log.Printf("Error dialing server %s: %v", conf.Server, err)
+		goto closeConns
+	}
+
+	// Send password.
+	if _, err = rConn.Write(conf.password); err != nil {
+		log.Printf("Error sending password: %v", err)
+		goto closeConns
+	}
+
+	// Forward traffic.
+	go io.Copy(lConn, rConn)
+	go io.Copy(rConn, lConn)
+	return
+
+closeConns:
+	lConn.Close()
+	if rConn != nil {
+		rConn.Close()
+	}
+}

gencerts.go

@@ -0,0 +1,72 @@
+package ttunnel
+
+import (
+	"bytes"
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"math/big"
+	"net"
+	"time"
+)
+
+func genCerts(password []byte, ip string) ([]byte, []byte) {
+	reader := NewRandReader(password)
+	defer reader.Close()
+
+	// Generate a private key.
+	priv, err := ecdsa.GenerateKey(elliptic.P521(), reader)
+	if err != nil {
+		panic("Failed to generate ECDSA key")
+	}
+
+	// Parse the IP address.
+	ipAddr := net.ParseIP(ip)
+	if ipAddr == nil {
+		panic("Invalid IP address: " + ip)
+	}
+
+	keyUsage := x509.KeyUsageKeyEncipherment |
+		x509.KeyUsageDigitalSignature |
+		x509.KeyUsageCertSign
+
+	template := x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		Subject:      pkix.Name{Organization: []string{"Acme Co"}},
+		NotBefore:    time.Unix(0, 0),
+		NotAfter:     time.Unix(0, 0).Add(200 * 365 * 24 * time.Hour),
+		KeyUsage:     keyUsage,
+		ExtKeyUsage:  []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		IsCA:         true,
+
+		BasicConstraintsValid: true,
+	}
+
+	template.IPAddresses = append(template.IPAddresses, ipAddr)
+
+	// Create the certificate.
+	derBytes, err := x509.CreateCertificate(
+		reader, &template, &template, &priv.PublicKey, priv)
+	if err != nil {
+		panic("Failed to create certificate: " + err.Error())
+	}
+
+	certBuf := new(bytes.Buffer)
+	pem.Encode(certBuf, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+
+	// Create the private keyl.
+	keyBuf := new(bytes.Buffer)
+	privBuf, err := x509.MarshalECPrivateKey(priv)
+	if err != nil {
+		panic("Failed to marshal ECDSA key: " + err.Error())
+	}
+	pem.Encode(keyBuf,
+		&pem.Block{
+			Type:  "RSA PRIVATE KEY",
+			Bytes: privBuf,
+		})
+
+	return keyBuf.Bytes(), certBuf.Bytes()
+}

gencerts_test.go

@@ -0,0 +1,22 @@
+package ttunnel
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestGenCertsMatch(t *testing.T) {
+	password := []byte("FlufHojNacMuabciCaiHijTinleHicAj")
+	ip := "192.168.0.102"
+
+	key1, cert1 := genCerts(password, ip)
+	key2, cert2 := genCerts(password, ip)
+
+	if !bytes.Equal(key1, key2) {
+		t.Fatal("Keys not equal")
+	}
+
+	if !bytes.Equal(cert1, cert2) {
+		t.Fatalf("Certs not equal: \n%s\n!=\n%s", string(cert1), string(cert2))
+	}
+}

main.go

@@ -0,0 +1,33 @@
+package ttunnel
+
+import (
+	"fmt"
+	"log"
+	"os"
+)
+
+var mainUsage = fmt.Sprintf(`Usage: %s command config-file
+
+Available commands:
+  server
+  client
+`, os.Args[0])
+
+func Main() {
+	if len(os.Args) != 3 {
+		log.Println(mainUsage)
+		os.Exit(1)
+	}
+
+	switch os.Args[1] {
+	case "server":
+		RunServer(os.Args[2])
+
+	case "client":
+		RunClient(os.Args[2])
+
+	default:
+		log.Println(mainUsage)
+		os.Exit(1)
+	}
+}

randreader.go

@@ -0,0 +1,66 @@
+package ttunnel
+
+import (
+	"crypto/sha512"
+	"hash"
+)
+
+// In order to generate matching certificates on a client and server, we need a
+// deterministic reader for random data. The reader is seeded with the
+// password and uses multiple hashings to generate additional bytes.
+type RandReader struct {
+	seed   []byte
+	close  chan bool
+	closed bool
+	stream chan byte
+	h      hash.Hash
+}
+
+func NewRandReader(seed []byte) *RandReader {
+	rr := RandReader{
+		seed:   seed,
+		close:  make(chan bool),
+		closed: false,
+		stream: make(chan byte),
+		h:      sha512.New(),
+	}
+	go rr.run()
+	return &rr
+}
+
+func (rr *RandReader) run() {
+	buf := []byte{}
+
+	for {
+		_, _ = rr.h.Write(rr.seed) // Never returns an error (see docs).
+		buf = buf[:]
+		buf = rr.h.Sum(buf)
+
+		for _, b := range buf {
+			select {
+			case <-rr.close:
+				rr.closed = true
+				return
+
+			case rr.stream <- b:
+				// Continue
+			}
+		}
+	}
+}
+
+func (rr *RandReader) Read(p []byte) (n int, err error) {
+	if rr.closed {
+		panic("Reading from closed RandReader")
+	}
+
+	for i := range p {
+		p[i] = <-rr.stream
+	}
+
+	return len(p), nil
+}
+
+func (rr *RandReader) Close() {
+	rr.close <- true
+}

randreader_test.go

@@ -0,0 +1,27 @@
+package ttunnel
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestRandReader(t *testing.T) {
+	seed := []byte("oushBafepGochCotlekcebvallAwJedd")
+	rr1 := NewRandReader(seed)
+	rr2 := NewRandReader(seed)
+
+	defer rr1.Close()
+	defer rr2.Close()
+
+	// Read some long buffers.
+	b1 := make([]byte, 32768)
+	b2 := make([]byte, 32768)
+
+	for i := 0; i < 8; i++ {
+		rr1.Read(b1)
+		rr2.Read(b2)
+		if !bytes.Equal(b1, b2) {
+			t.Fatal("Not equal!")
+		}
+	}
+}

server.go

@@ -0,0 +1,91 @@
+package ttunnel
+
+import (
+	"crypto/subtle"
+	"crypto/tls"
+	"io"
+	"log"
+	"net"
+	"strings"
+
+	"github.com/BurntSushi/toml"
+)
+
+type ServerConfig struct {
+	Listen   string // Must be IP:port.
+	Forward  string
+	Password string
+	password []byte
+}
+
+func (sc ServerConfig) IP() string {
+	return strings.Split(sc.Listen, ":")[0]
+}
+
+func RunServer(path string) {
+	conf := ServerConfig{}
+	_, err := toml.DecodeFile(path, &conf)
+	if err != nil {
+		log.Printf("Failed to load config file %s: %v", path, err)
+		return
+	}
+	conf.password = []byte(conf.Password)
+
+	keyBuf, certBuf := genCerts(conf.password, conf.IP())
+	cert, err := tls.X509KeyPair(certBuf, keyBuf)
+	if err != nil {
+		log.Printf("Failed to create X509 key pair: %v", err)
+		return
+	}
+
+	// Create TLS configuration for the server.
+	config := tls.Config{Certificates: []tls.Certificate{cert}}
+
+	// Accept connections on the given address.
+	ln, err := tls.Listen("tcp", conf.Listen, &config)
+	if err != nil {
+		log.Printf("Failed to listen on %s: %v", conf.Listen, err)
+		return
+	}
+
+	for {
+		conn, err := ln.Accept()
+		if err != nil {
+			log.Printf("Failed to accept connection: %v", err)
+			continue
+		}
+
+		go serverHandler(conn, conf)
+	}
+}
+
+func serverHandler(conn net.Conn, conf ServerConfig) {
+	var err error
+	var cConn net.Conn // Client connection.
+
+	buf := make([]byte, len(conf.Password))
+	if _, err = conn.Read(buf); err != nil {
+		log.Printf("Failed to read password: %v", err)
+		goto closeConn
+	}
+
+	if subtle.ConstantTimeCompare(buf, conf.password) != 1 {
+		log.Printf("Invalid password provided")
+		goto closeConn
+	}
+
+	// Connect to the remote address for the client.
+	cConn, err = net.Dial("tcp", conf.Forward)
+	if err != nil {
+		log.Printf("Failed to connect to host %s: %v", conf.Forward, err)
+		goto closeConn
+	}
+
+	// Forward traffic.
+	go io.Copy(cConn, conn)
+	go io.Copy(conn, cConn)
+	return
+
+closeConn:
+	conn.Close()
+}

vendor/github.com/BurntSushi/toml/.gitignore

@@ -0,0 +1,5 @@
+TAGS
+tags
+.*.swp
+tomlcheck/tomlcheck
+toml.test

vendor/github.com/BurntSushi/toml/.travis.yml

@@ -0,0 +1,15 @@
+language: go
+go:
+  - 1.1
+  - 1.2
+  - 1.3
+  - 1.4
+  - 1.5
+  - 1.6
+  - tip
+install:
+  - go install ./...
+  - go get github.com/BurntSushi/toml-test
+script:
+  - export PATH="$PATH:$HOME/gopath/bin"
+  - make test

vendor/github.com/BurntSushi/toml/COMPATIBLE

@@ -0,0 +1,3 @@
+Compatible with TOML version
+[v0.2.0](https://github.com/mojombo/toml/blob/master/versions/toml-v0.2.0.md)
+

vendor/github.com/BurntSushi/toml/COPYING

@@ -0,0 +1,14 @@
+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+                    Version 2, December 2004
+
+ Copyright (C) 2004 Sam Hocevar <sam@hocevar.net>
+
+ Everyone is permitted to copy and distribute verbatim or modified
+ copies of this license document, and changing it is allowed as long
+ as the name is changed.
+
+            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. You just DO WHAT THE FUCK YOU WANT TO.
+

vendor/github.com/BurntSushi/toml/Makefile

@@ -0,0 +1,19 @@
+install:
+	go install ./...
+
+test: install
+	go test -v
+	toml-test toml-test-decoder
+	toml-test -encoder toml-test-encoder
+
+fmt:
+	gofmt -w *.go */*.go
+	colcheck *.go */*.go
+
+tags:
+	find ./ -name '*.go' -print0 | xargs -0 gotags > TAGS
+
+push:
+	git push origin master
+	git push github master
+

vendor/github.com/BurntSushi/toml/README.md

@@ -0,0 +1,220 @@
+## TOML parser and encoder for Go with reflection
+
+TOML stands for Tom's Obvious, Minimal Language. This Go package provides a
+reflection interface similar to Go's standard library `json` and `xml` 
+packages. This package also supports the `encoding.TextUnmarshaler` and
+`encoding.TextMarshaler` interfaces so that you can define custom data 
+representations. (There is an example of this below.)
+
+Spec: https://github.com/mojombo/toml
+
+Compatible with TOML version
+[v0.2.0](https://github.com/toml-lang/toml/blob/master/versions/en/toml-v0.2.0.md)
+
+Documentation: http://godoc.org/github.com/BurntSushi/toml
+
+Installation:
+
+```bash
+go get github.com/BurntSushi/toml
+```
+
+Try the toml validator:
+
+```bash
+go get github.com/BurntSushi/toml/cmd/tomlv
+tomlv some-toml-file.toml
+```
+
+[![Build status](https://api.travis-ci.org/BurntSushi/toml.png)](https://travis-ci.org/BurntSushi/toml)
+
+
+### Testing
+
+This package passes all tests in
+[toml-test](https://github.com/BurntSushi/toml-test) for both the decoder
+and the encoder.
+
+### Examples
+
+This package works similarly to how the Go standard library handles `XML`
+and `JSON`. Namely, data is loaded into Go values via reflection.
+
+For the simplest example, consider some TOML file as just a list of keys
+and values:
+
+```toml
+Age = 25
+Cats = [ "Cauchy", "Plato" ]
+Pi = 3.14
+Perfection = [ 6, 28, 496, 8128 ]
+DOB = 1987-07-05T05:45:00Z
+```
+
+Which could be defined in Go as:
+
+```go
+type Config struct {
+  Age int
+  Cats []string
+  Pi float64
+  Perfection []int
+  DOB time.Time // requires `import time`
+}
+```
+
+And then decoded with:
+
+```go
+var conf Config
+if _, err := toml.Decode(tomlData, &conf); err != nil {
+  // handle error
+}
+```
+
+You can also use struct tags if your struct field name doesn't map to a TOML
+key value directly:
+
+```toml
+some_key_NAME = "wat"
+```
+
+```go
+type TOML struct {
+  ObscureKey string `toml:"some_key_NAME"`
+}
+```
+
+### Using the `encoding.TextUnmarshaler` interface
+
+Here's an example that automatically parses duration strings into 
+`time.Duration` values:
+
+```toml
+[[song]]
+name = "Thunder Road"
+duration = "4m49s"
+
+[[song]]
+name = "Stairway to Heaven"
+duration = "8m03s"
+```
+
+Which can be decoded with:
+
+```go
+type song struct {
+  Name     string
+  Duration duration
+}
+type songs struct {
+  Song []song
+}
+var favorites songs
+if _, err := toml.Decode(blob, &favorites); err != nil {
+  log.Fatal(err)
+}
+
+for _, s := range favorites.Song {
+  fmt.Printf("%s (%s)\n", s.Name, s.Duration)
+}
+```
+
+And you'll also need a `duration` type that satisfies the 
+`encoding.TextUnmarshaler` interface:
+
+```go
+type duration struct {
+	time.Duration
+}
+
+func (d *duration) UnmarshalText(text []byte) error {
+	var err error
+	d.Duration, err = time.ParseDuration(string(text))
+	return err
+}
+```
+
+### More complex usage
+
+Here's an example of how to load the example from the official spec page:
+
+```toml
+# This is a TOML document. Boom.
+
+title = "TOML Example"
+
+[owner]
+name = "Tom Preston-Werner"
+organization = "GitHub"
+bio = "GitHub Cofounder & CEO\nLikes tater tots and beer."
+dob = 1979-05-27T07:32:00Z # First class dates? Why not?
+
+[database]
+server = "192.168.1.1"
+ports = [ 8001, 8001, 8002 ]
+connection_max = 5000
+enabled = true
+
+[servers]
+
+  # You can indent as you please. Tabs or spaces. TOML don't care.
+  [servers.alpha]
+  ip = "10.0.0.1"
+  dc = "eqdc10"
+
+  [servers.beta]
+  ip = "10.0.0.2"
+  dc = "eqdc10"
+
+[clients]
+data = [ ["gamma", "delta"], [1, 2] ] # just an update to make sure parsers support it
+
+# Line breaks are OK when inside arrays
+hosts = [
+  "alpha",
+  "omega"
+]
+```
+
+And the corresponding Go types are:
+
+```go
+type tomlConfig struct {
+	Title string
+	Owner ownerInfo
+	DB database `toml:"database"`
+	Servers map[string]server
+	Clients clients
+}
+
+type ownerInfo struct {
+	Name string
+	Org string `toml:"organization"`
+	Bio string
+	DOB time.Time
+}
+
+type database struct {
+	Server string
+	Ports []int
+	ConnMax int `toml:"connection_max"`
+	Enabled bool
+}
+
+type server struct {
+	IP string
+	DC string
+}
+
+type clients struct {
+	Data [][]interface{}
+	Hosts []string
+}
+```
+
+Note that a case insensitive match will be tried if an exact match can't be
+found.
+
+A working example of the above can be found in `_examples/example.{go,toml}`.
+

vendor/github.com/BurntSushi/toml/decode.go

@@ -0,0 +1,509 @@
+package toml
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"math"
+	"reflect"
+	"strings"
+	"time"
+)
+
+func e(format string, args ...interface{}) error {
+	return fmt.Errorf("toml: "+format, args...)
+}
+
+// Unmarshaler is the interface implemented by objects that can unmarshal a
+// TOML description of themselves.
+type Unmarshaler interface {
+	UnmarshalTOML(interface{}) error
+}
+
+// Unmarshal decodes the contents of `p` in TOML format into a pointer `v`.
+func Unmarshal(p []byte, v interface{}) error {
+	_, err := Decode(string(p), v)
+	return err
+}
+
+// Primitive is a TOML value that hasn't been decoded into a Go value.
+// When using the various `Decode*` functions, the type `Primitive` may
+// be given to any value, and its decoding will be delayed.
+//
+// A `Primitive` value can be decoded using the `PrimitiveDecode` function.
+//
+// The underlying representation of a `Primitive` value is subject to change.
+// Do not rely on it.
+//
+// N.B. Primitive values are still parsed, so using them will only avoid
+// the overhead of reflection. They can be useful when you don't know the
+// exact type of TOML data until run time.
+type Primitive struct {
+	undecoded interface{}
+	context   Key
+}
+
+// DEPRECATED!
+//
+// Use MetaData.PrimitiveDecode instead.
+func PrimitiveDecode(primValue Primitive, v interface{}) error {
+	md := MetaData{decoded: make(map[string]bool)}
+	return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// PrimitiveDecode is just like the other `Decode*` functions, except it
+// decodes a TOML value that has already been parsed. Valid primitive values
+// can *only* be obtained from values filled by the decoder functions,
+// including this method. (i.e., `v` may contain more `Primitive`
+// values.)
+//
+// Meta data for primitive values is included in the meta data returned by
+// the `Decode*` functions with one exception: keys returned by the Undecoded
+// method will only reflect keys that were decoded. Namely, any keys hidden
+// behind a Primitive will be considered undecoded. Executing this method will
+// update the undecoded keys in the meta data. (See the example.)
+func (md *MetaData) PrimitiveDecode(primValue Primitive, v interface{}) error {
+	md.context = primValue.context
+	defer func() { md.context = nil }()
+	return md.unify(primValue.undecoded, rvalue(v))
+}
+
+// Decode will decode the contents of `data` in TOML format into a pointer
+// `v`.
+//
+// TOML hashes correspond to Go structs or maps. (Dealer's choice. They can be
+// used interchangeably.)
+//
+// TOML arrays of tables correspond to either a slice of structs or a slice
+// of maps.
+//
+// TOML datetimes correspond to Go `time.Time` values.
+//
+// All other TOML types (float, string, int, bool and array) correspond
+// to the obvious Go types.
+//
+// An exception to the above rules is if a type implements the
+// encoding.TextUnmarshaler interface. In this case, any primitive TOML value
+// (floats, strings, integers, booleans and datetimes) will be converted to
+// a byte string and given to the value's UnmarshalText method. See the
+// Unmarshaler example for a demonstration with time duration strings.
+//
+// Key mapping
+//
+// TOML keys can map to either keys in a Go map or field names in a Go
+// struct. The special `toml` struct tag may be used to map TOML keys to
+// struct fields that don't match the key name exactly. (See the example.)
+// A case insensitive match to struct names will be tried if an exact match
+// can't be found.
+//
+// The mapping between TOML values and Go values is loose. That is, there
+// may exist TOML values that cannot be placed into your representation, and
+// there may be parts of your representation that do not correspond to
+// TOML values. This loose mapping can be made stricter by using the IsDefined
+// and/or Undecoded methods on the MetaData returned.
+//
+// This decoder will not handle cyclic types. If a cyclic type is passed,
+// `Decode` will not terminate.
+func Decode(data string, v interface{}) (MetaData, error) {
+	rv := reflect.ValueOf(v)
+	if rv.Kind() != reflect.Ptr {
+		return MetaData{}, e("Decode of non-pointer %s", reflect.TypeOf(v))
+	}
+	if rv.IsNil() {
+		return MetaData{}, e("Decode of nil %s", reflect.TypeOf(v))
+	}
+	p, err := parse(data)
+	if err != nil {
+		return MetaData{}, err
+	}
+	md := MetaData{
+		p.mapping, p.types, p.ordered,
+		make(map[string]bool, len(p.ordered)), nil,
+	}
+	return md, md.unify(p.mapping, indirect(rv))
+}
+
+// DecodeFile is just like Decode, except it will automatically read the
+// contents of the file at `fpath` and decode it for you.
+func DecodeFile(fpath string, v interface{}) (MetaData, error) {
+	bs, err := ioutil.ReadFile(fpath)
+	if err != nil {
+		return MetaData{}, err
+	}
+	return Decode(string(bs), v)
+}
+
+// DecodeReader is just like Decode, except it will consume all bytes
+// from the reader and decode it for you.
+func DecodeReader(r io.Reader, v interface{}) (MetaData, error) {
+	bs, err := ioutil.ReadAll(r)
+	if err != nil {
+		return MetaData{}, err
+	}
+	return Decode(string(bs), v)
+}
+
+// unify performs a sort of type unification based on the structure of `rv`,
+// which is the client representation.
+//
+// Any type mismatch produces an error. Finding a type that we don't know
+// how to handle produces an unsupported type error.
+func (md *MetaData) unify(data interface{}, rv reflect.Value) error {
+
+	// Special case. Look for a `Primitive` value.
+	if rv.Type() == reflect.TypeOf((*Primitive)(nil)).Elem() {
+		// Save the undecoded data and the key context into the primitive
+		// value.
+		context := make(Key, len(md.context))
+		copy(context, md.context)
+		rv.Set(reflect.ValueOf(Primitive{
+			undecoded: data,
+			context:   context,
+		}))
+		return nil
+	}
+
+	// Special case. Unmarshaler Interface support.
+	if rv.CanAddr() {
+		if v, ok := rv.Addr().Interface().(Unmarshaler); ok {
+			return v.UnmarshalTOML(data)
+		}
+	}
+
+	// Special case. Handle time.Time values specifically.
+	// TODO: Remove this code when we decide to drop support for Go 1.1.
+	// This isn't necessary in Go 1.2 because time.Time satisfies the encoding
+	// interfaces.
+	if rv.Type().AssignableTo(rvalue(time.Time{}).Type()) {
+		return md.unifyDatetime(data, rv)
+	}
+
+	// Special case. Look for a value satisfying the TextUnmarshaler interface.
+	if v, ok := rv.Interface().(TextUnmarshaler); ok {
+		return md.unifyText(data, v)
+	}
+	// BUG(burntsushi)
+	// The behavior here is incorrect whenever a Go type satisfies the
+	// encoding.TextUnmarshaler interface but also corresponds to a TOML
+	// hash or array. In particular, the unmarshaler should only be applied
+	// to primitive TOML values. But at this point, it will be applied to
+	// all kinds of values and produce an incorrect error whenever those values
+	// are hashes or arrays (including arrays of tables).
+
+	k := rv.Kind()
+
+	// laziness
+	if k >= reflect.Int && k <= reflect.Uint64 {
+		return md.unifyInt(data, rv)
+	}
+	switch k {
+	case reflect.Ptr:
+		elem := reflect.New(rv.Type().Elem())
+		err := md.unify(data, reflect.Indirect(elem))
+		if err != nil {
+			return err
+		}
+		rv.Set(elem)
+		return nil
+	case reflect.Struct:
+		return md.unifyStruct(data, rv)
+	case reflect.Map:
+		return md.unifyMap(data, rv)
+	case reflect.Array:
+		return md.unifyArray(data, rv)
+	case reflect.Slice:
+		return md.unifySlice(data, rv)
+	case reflect.String:
+		return md.unifyString(data, rv)
+	case reflect.Bool:
+		return md.unifyBool(data, rv)
+	case reflect.Interface:
+		// we only support empty interfaces.
+		if rv.NumMethod() > 0 {
+			return e("unsupported type %s", rv.Type())
+		}
+		return md.unifyAnything(data, rv)
+	case reflect.Float32:
+		fallthrough
+	case reflect.Float64:
+		return md.unifyFloat64(data, rv)
+	}
+	return e("unsupported type %s", rv.Kind())
+}
+
+func (md *MetaData) unifyStruct(mapping interface{}, rv reflect.Value) error {
+	tmap, ok := mapping.(map[string]interface{})
+	if !ok {
+		if mapping == nil {
+			return nil
+		}
+		return e("type mismatch for %s: expected table but found %T",
+			rv.Type().String(), mapping)
+	}
+
+	for key, datum := range tmap {
+		var f *field
+		fields := cachedTypeFields(rv.Type())
+		for i := range fields {
+			ff := &fields[i]
+			if ff.name == key {
+				f = ff
+				break
+			}
+			if f == nil && strings.EqualFold(ff.name, key) {
+				f = ff
+			}
+		}
+		if f != nil {
+			subv := rv
+			for _, i := range f.index {
+				subv = indirect(subv.Field(i))
+			}
+			if isUnifiable(subv) {
+				md.decoded[md.context.add(key).String()] = true
+				md.context = append(md.context, key)
+				if err := md.unify(datum, subv); err != nil {
+					return err
+				}
+				md.context = md.context[0 : len(md.context)-1]
+			} else if f.name != "" {
+				// Bad user! No soup for you!
+				return e("cannot write unexported field %s.%s",
+					rv.Type().String(), f.name)
+			}
+		}
+	}
+	return nil
+}
+
+func (md *MetaData) unifyMap(mapping interface{}, rv reflect.Value) error {
+	tmap, ok := mapping.(map[string]interface{})
+	if !ok {
+		if tmap == nil {
+			return nil
+		}
+		return badtype("map", mapping)
+	}
+	if rv.IsNil() {
+		rv.Set(reflect.MakeMap(rv.Type()))
+	}
+	for k, v := range tmap {
+		md.decoded[md.context.add(k).String()] = true
+		md.context = append(md.context, k)
+
+		rvkey := indirect(reflect.New(rv.Type().Key()))
+		rvval := reflect.Indirect(reflect.New(rv.Type().Elem()))
+		if err := md.unify(v, rvval); err != nil {
+			return err
+		}
+		md.context = md.context[0 : len(md.context)-1]
+
+		rvkey.SetString(k)
+		rv.SetMapIndex(rvkey, rvval)
+	}
+	return nil
+}
+
+func (md *MetaData) unifyArray(data interface{}, rv reflect.Value) error {
+	datav := reflect.ValueOf(data)
+	if datav.Kind() != reflect.Slice {
+		if !datav.IsValid() {
+			return nil
+		}
+		return badtype("slice", data)
+	}
+	sliceLen := datav.Len()
+	if sliceLen != rv.Len() {
+		return e("expected array length %d; got TOML array of length %d",
+			rv.Len(), sliceLen)
+	}
+	return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySlice(data interface{}, rv reflect.Value) error {
+	datav := reflect.ValueOf(data)
+	if datav.Kind() != reflect.Slice {
+		if !datav.IsValid() {
+			return nil
+		}
+		return badtype("slice", data)
+	}
+	n := datav.Len()
+	if rv.IsNil() || rv.Cap() < n {
+		rv.Set(reflect.MakeSlice(rv.Type(), n, n))
+	}
+	rv.SetLen(n)
+	return md.unifySliceArray(datav, rv)
+}
+
+func (md *MetaData) unifySliceArray(data, rv reflect.Value) error {
+	sliceLen := data.Len()
+	for i := 0; i < sliceLen; i++ {
+		v := data.Index(i).Interface()
+		sliceval := indirect(rv.Index(i))
+		if err := md.unify(v, sliceval); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (md *MetaData) unifyDatetime(data interface{}, rv reflect.Value) error {
+	if _, ok := data.(time.Time); ok {
+		rv.Set(reflect.ValueOf(data))
+		return nil
+	}
+	return badtype("time.Time", data)
+}
+
+func (md *MetaData) unifyString(data interface{}, rv reflect.Value) error {
+	if s, ok := data.(string); ok {
+		rv.SetString(s)
+		return nil
+	}
+	return badtype("string", data)
+}
+
+func (md *MetaData) unifyFloat64(data interface{}, rv reflect.Value) error {
+	if num, ok := data.(float64); ok {
+		switch rv.Kind() {
+		case reflect.Float32:
+			fallthrough
+		case reflect.Float64:
+			rv.SetFloat(num)
+		default:
+			panic("bug")
+		}
+		return nil
+	}
+	return badtype("float", data)
+}
+
+func (md *MetaData) unifyInt(data interface{}, rv reflect.Value) error {
+	if num, ok := data.(int64); ok {
+		if rv.Kind() >= reflect.Int && rv.Kind() <= reflect.Int64 {
+			switch rv.Kind() {
+			case reflect.Int, reflect.Int64:
+				// No bounds checking necessary.
+			case reflect.Int8:
+				if num < math.MinInt8 || num > math.MaxInt8 {
+					return e("value %d is out of range for int8", num)
+				}
+			case reflect.Int16:
+				if num < math.MinInt16 || num > math.MaxInt16 {
+					return e("value %d is out of range for int16", num)
+				}
+			case reflect.Int32:
+				if num < math.MinInt32 || num > math.MaxInt32 {
+					return e("value %d is out of range for int32", num)
+				}
+			}
+			rv.SetInt(num)
+		} else if rv.Kind() >= reflect.Uint && rv.Kind() <= reflect.Uint64 {
+			unum := uint64(num)
+			switch rv.Kind() {
+			case reflect.Uint, reflect.Uint64:
+				// No bounds checking necessary.
+			case reflect.Uint8:
+				if num < 0 || unum > math.MaxUint8 {
+					return e("value %d is out of range for uint8", num)
+				}
+			case reflect.Uint16:
+				if num < 0 || unum > math.MaxUint16 {
+					return e("value %d is out of range for uint16", num)
+				}
+			case reflect.Uint32:
+				if num < 0 || unum > math.MaxUint32 {
+					return e("value %d is out of range for uint32", num)
+				}
+			}
+			rv.SetUint(unum)
+		} else {
+			panic("unreachable")
+		}
+		return nil
+	}
+	return badtype("integer", data)
+}
+
+func (md *MetaData) unifyBool(data interface{}, rv reflect.Value) error {
+	if b, ok := data.(bool); ok {
+		rv.SetBool(b)
+		return nil
+	}
+	return badtype("boolean", data)
+}
+
+func (md *MetaData) unifyAnything(data interface{}, rv reflect.Value) error {
+	rv.Set(reflect.ValueOf(data))
+	return nil
+}
+
+func (md *MetaData) unifyText(data interface{}, v TextUnmarshaler) error {
+	var s string
+	switch sdata := data.(type) {
+	case TextMarshaler:
+		text, err := sdata.MarshalText()
+		if err != nil {
+			return err
+		}
+		s = string(text)
+	case fmt.Stringer:
+		s = sdata.String()
+	case string:
+		s = sdata
+	case bool:
+		s = fmt.Sprintf("%v", sdata)
+	case int64:
+		s = fmt.Sprintf("%d", sdata)
+	case float64:
+		s = fmt.Sprintf("%f", sdata)
+	default:
+		return badtype("primitive (string-like)", data)
+	}
+	if err := v.UnmarshalText([]byte(s)); err != nil {
+		return err
+	}
+	return nil
+}
+
+// rvalue returns a reflect.Value of `v`. All pointers are resolved.
+func rvalue(v interface{}) reflect.Value {
+	return indirect(reflect.ValueOf(v))
+}
+
+// indirect returns the value pointed to by a pointer.
+// Pointers are followed until the value is not a pointer.
+// New values are allocated for each nil pointer.
+//
+// An exception to this rule is if the value satisfies an interface of
+// interest to us (like encoding.TextUnmarshaler).
+func indirect(v reflect.Value) reflect.Value {
+	if v.Kind() != reflect.Ptr {
+		if v.CanSet() {
+			pv := v.Addr()
+			if _, ok := pv.Interface().(TextUnmarshaler); ok {
+				return pv
+			}
+		}
+		return v
+	}
+	if v.IsNil() {
+		v.Set(reflect.New(v.Type().Elem()))
+	}
+	return indirect(reflect.Indirect(v))
+}
+
+func isUnifiable(rv reflect.Value) bool {
+	if rv.CanSet() {
+		return true
+	}
+	if _, ok := rv.Interface().(TextUnmarshaler); ok {
+		return true
+	}
+	return false
+}
+
+func badtype(expected string, data interface{}) error {
+	return e("cannot load TOML value of type %T into a Go %s", data, expected)
+}

vendor/github.com/BurntSushi/toml/decode_meta.go

@@ -0,0 +1,121 @@
+package toml
+
+import "strings"
+
+// MetaData allows access to meta information about TOML data that may not
+// be inferrable via reflection. In particular, whether a key has been defined
+// and the TOML type of a key.
+type MetaData struct {
+	mapping map[string]interface{}
+	types   map[string]tomlType
+	keys    []Key
+	decoded map[string]bool
+	context Key // Used only during decoding.
+}
+
+// IsDefined returns true if the key given exists in the TOML data. The key
+// should be specified hierarchially. e.g.,
+//
+//	// access the TOML key 'a.b.c'
+//	IsDefined("a", "b", "c")
+//
+// IsDefined will return false if an empty key given. Keys are case sensitive.
+func (md *MetaData) IsDefined(key ...string) bool {
+	if len(key) == 0 {
+		return false
+	}
+
+	var hash map[string]interface{}
+	var ok bool
+	var hashOrVal interface{} = md.mapping
+	for _, k := range key {
+		if hash, ok = hashOrVal.(map[string]interface{}); !ok {
+			return false
+		}
+		if hashOrVal, ok = hash[k]; !ok {
+			return false
+		}
+	}
+	return true
+}
+
+// Type returns a string representation of the type of the key specified.
+//
+// Type will return the empty string if given an empty key or a key that
+// does not exist. Keys are case sensitive.
+func (md *MetaData) Type(key ...string) string {
+	fullkey := strings.Join(key, ".")
+	if typ, ok := md.types[fullkey]; ok {
+		return typ.typeString()
+	}
+	return ""
+}
+
+// Key is the type of any TOML key, including key groups. Use (MetaData).Keys
+// to get values of this type.
+type Key []string
+
+func (k Key) String() string {
+	return strings.Join(k, ".")
+}
+
+func (k Key) maybeQuotedAll() string {
+	var ss []string
+	for i := range k {
+		ss = append(ss, k.maybeQuoted(i))
+	}
+	return strings.Join(ss, ".")
+}
+
+func (k Key) maybeQuoted(i int) string {
+	quote := false
+	for _, c := range k[i] {
+		if !isBareKeyChar(c) {
+			quote = true
+			break
+		}
+	}
+	if quote {
+		return "\"" + strings.Replace(k[i], "\"", "\\\"", -1) + "\""
+	}
+	return k[i]
+}
+
+func (k Key) add(piece string) Key {
+	newKey := make(Key, len(k)+1)
+	copy(newKey, k)
+	newKey[len(k)] = piece
+	return newKey
+}
+
+// Keys returns a slice of every key in the TOML data, including key groups.
+// Each key is itself a slice, where the first element is the top of the
+// hierarchy and the last is the most specific.
+//
+// The list will have the same order as the keys appeared in the TOML data.
+//
+// All keys returned are non-empty.
+func (md *MetaData) Keys() []Key {
+	return md.keys
+}
+
+// Undecoded returns all keys that have not been decoded in the order in which
+// they appear in the original TOML document.
+//
+// This includes keys that haven't been decoded because of a Primitive value.
+// Once the Primitive value is decoded, the keys will be considered decoded.
+//
+// Also note that decoding into an empty interface will result in no decoding,
+// and so no keys will be considered decoded.
+//
+// In this sense, the Undecoded keys correspond to keys in the TOML document
+// that do not have a concrete type in your representation.
+func (md *MetaData) Undecoded() []Key {
+	undecoded := make([]Key, 0, len(md.keys))
+	for _, key := range md.keys {
+		if !md.decoded[key.String()] {
+			undecoded = append(undecoded, key)
+		}
+	}
+	return undecoded
+}

vendor/github.com/BurntSushi/toml/doc.go

@@ -0,0 +1,27 @@
+/*
+Package toml provides facilities for decoding and encoding TOML configuration
+files via reflection. There is also support for delaying decoding with
+the Primitive type, and querying the set of keys in a TOML document with the
+MetaData type.
+
+The specification implemented: https://github.com/mojombo/toml
+
+The sub-command github.com/BurntSushi/toml/cmd/tomlv can be used to verify
+whether a file is a valid TOML document. It can also be used to print the
+type of each key in a TOML document.
+
+Testing
+
+There are two important types of tests used for this package. The first is
+contained inside '*_test.go' files and uses the standard Go unit testing
+framework. These tests are primarily devoted to holistically testing the
+decoder and encoder.
+
+The second type of testing is used to verify the implementation's adherence
+to the TOML specification. These tests have been factored into their own
+project: https://github.com/BurntSushi/toml-test
+
+The reason the tests are in a separate project is so that they can be used by
+any implementation of TOML. Namely, it is language agnostic.
+*/
+package toml

vendor/github.com/BurntSushi/toml/encode.go

@@ -0,0 +1,568 @@
+package toml
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+)
+
+type tomlEncodeError struct{ error }
+
+var (
+	errArrayMixedElementTypes = errors.New(
+		"toml: cannot encode array with mixed element types")
+	errArrayNilElement = errors.New(
+		"toml: cannot encode array with nil element")
+	errNonString = errors.New(
+		"toml: cannot encode a map with non-string key type")
+	errAnonNonStruct = errors.New(
+		"toml: cannot encode an anonymous field that is not a struct")
+	errArrayNoTable = errors.New(
+		"toml: TOML array element cannot contain a table")
+	errNoKey = errors.New(
+		"toml: top-level values must be Go maps or structs")
+	errAnything = errors.New("") // used in testing
+)
+
+var quotedReplacer = strings.NewReplacer(
+	"\t", "\\t",
+	"\n", "\\n",
+	"\r", "\\r",
+	"\"", "\\\"",
+	"\\", "\\\\",
+)
+
+// Encoder controls the encoding of Go values to a TOML document to some
+// io.Writer.
+//
+// The indentation level can be controlled with the Indent field.
+type Encoder struct {
+	// A single indentation level. By default it is two spaces.
+	Indent string
+
+	// hasWritten is whether we have written any output to w yet.
+	hasWritten bool
+	w          *bufio.Writer
+}
+
+// NewEncoder returns a TOML encoder that encodes Go values to the io.Writer
+// given. By default, a single indentation level is 2 spaces.
+func NewEncoder(w io.Writer) *Encoder {
+	return &Encoder{
+		w:      bufio.NewWriter(w),
+		Indent: "  ",
+	}
+}
+
+// Encode writes a TOML representation of the Go value to the underlying
+// io.Writer. If the value given cannot be encoded to a valid TOML document,
+// then an error is returned.
+//
+// The mapping between Go values and TOML values should be precisely the same
+// as for the Decode* functions. Similarly, the TextMarshaler interface is
+// supported by encoding the resulting bytes as strings. (If you want to write
+// arbitrary binary data then you will need to use something like base64 since
+// TOML does not have any binary types.)
+//
+// When encoding TOML hashes (i.e., Go maps or structs), keys without any
+// sub-hashes are encoded first.
+//
+// If a Go map is encoded, then its keys are sorted alphabetically for
+// deterministic output. More control over this behavior may be provided if
+// there is demand for it.
+//
+// Encoding Go values without a corresponding TOML representation---like map
+// types with non-string keys---will cause an error to be returned. Similarly
+// for mixed arrays/slices, arrays/slices with nil elements, embedded
+// non-struct types and nested slices containing maps or structs.
+// (e.g., [][]map[string]string is not allowed but []map[string]string is OK
+// and so is []map[string][]string.)
+func (enc *Encoder) Encode(v interface{}) error {
+	rv := eindirect(reflect.ValueOf(v))
+	if err := enc.safeEncode(Key([]string{}), rv); err != nil {
+		return err
+	}
+	return enc.w.Flush()
+}
+
+func (enc *Encoder) safeEncode(key Key, rv reflect.Value) (err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			if terr, ok := r.(tomlEncodeError); ok {
+				err = terr.error
+				return
+			}
+			panic(r)
+		}
+	}()
+	enc.encode(key, rv)
+	return nil
+}
+
+func (enc *Encoder) encode(key Key, rv reflect.Value) {
+	// Special case. Time needs to be in ISO8601 format.
+	// Special case. If we can marshal the type to text, then we used that.
+	// Basically, this prevents the encoder for handling these types as
+	// generic structs (or whatever the underlying type of a TextMarshaler is).
+	switch rv.Interface().(type) {
+	case time.Time, TextMarshaler:
+		enc.keyEqElement(key, rv)
+		return
+	}
+
+	k := rv.Kind()
+	switch k {
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32,
+		reflect.Int64,
+		reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32,
+		reflect.Uint64,
+		reflect.Float32, reflect.Float64, reflect.String, reflect.Bool:
+		enc.keyEqElement(key, rv)
+	case reflect.Array, reflect.Slice:
+		if typeEqual(tomlArrayHash, tomlTypeOfGo(rv)) {
+			enc.eArrayOfTables(key, rv)
+		} else {
+			enc.keyEqElement(key, rv)
+		}
+	case reflect.Interface:
+		if rv.IsNil() {
+			return
+		}
+		enc.encode(key, rv.Elem())
+	case reflect.Map:
+		if rv.IsNil() {
+			return
+		}
+		enc.eTable(key, rv)
+	case reflect.Ptr:
+		if rv.IsNil() {
+			return
+		}
+		enc.encode(key, rv.Elem())
+	case reflect.Struct:
+		enc.eTable(key, rv)
+	default:
+		panic(e("unsupported type for key '%s': %s", key, k))
+	}
+}
+
+// eElement encodes any value that can be an array element (primitives and
+// arrays).
+func (enc *Encoder) eElement(rv reflect.Value) {
+	switch v := rv.Interface().(type) {
+	case time.Time:
+		// Special case time.Time as a primitive. Has to come before
+		// TextMarshaler below because time.Time implements
+		// encoding.TextMarshaler, but we need to always use UTC.
+		enc.wf(v.UTC().Format("2006-01-02T15:04:05Z"))
+		return
+	case TextMarshaler:
+		// Special case. Use text marshaler if it's available for this value.
+		if s, err := v.MarshalText(); err != nil {
+			encPanic(err)
+		} else {
+			enc.writeQuoted(string(s))
+		}
+		return
+	}
+	switch rv.Kind() {
+	case reflect.Bool:
+		enc.wf(strconv.FormatBool(rv.Bool()))
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32,
+		reflect.Int64:
+		enc.wf(strconv.FormatInt(rv.Int(), 10))
+	case reflect.Uint, reflect.Uint8, reflect.Uint16,
+		reflect.Uint32, reflect.Uint64:
+		enc.wf(strconv.FormatUint(rv.Uint(), 10))
+	case reflect.Float32:
+		enc.wf(floatAddDecimal(strconv.FormatFloat(rv.Float(), 'f', -1, 32)))
+	case reflect.Float64:
+		enc.wf(floatAddDecimal(strconv.FormatFloat(rv.Float(), 'f', -1, 64)))
+	case reflect.Array, reflect.Slice:
+		enc.eArrayOrSliceElement(rv)
+	case reflect.Interface:
+		enc.eElement(rv.Elem())
+	case reflect.String:
+		enc.writeQuoted(rv.String())
+	default:
+		panic(e("unexpected primitive type: %s", rv.Kind()))
+	}
+}
+
+// By the TOML spec, all floats must have a decimal with at least one
+// number on either side.
+func floatAddDecimal(fstr string) string {
+	if !strings.Contains(fstr, ".") {
+		return fstr + ".0"
+	}
+	return fstr
+}
+
+func (enc *Encoder) writeQuoted(s string) {
+	enc.wf("\"%s\"", quotedReplacer.Replace(s))
+}
+
+func (enc *Encoder) eArrayOrSliceElement(rv reflect.Value) {
+	length := rv.Len()
+	enc.wf("[")
+	for i := 0; i < length; i++ {
+		elem := rv.Index(i)
+		enc.eElement(elem)
+		if i != length-1 {
+			enc.wf(", ")
+		}
+	}
+	enc.wf("]")
+}
+
+func (enc *Encoder) eArrayOfTables(key Key, rv reflect.Value) {
+	if len(key) == 0 {
+		encPanic(errNoKey)
+	}
+	for i := 0; i < rv.Len(); i++ {
+		trv := rv.Index(i)
+		if isNil(trv) {
+			continue
+		}
+		panicIfInvalidKey(key)
+		enc.newline()
+		enc.wf("%s[[%s]]", enc.indentStr(key), key.maybeQuotedAll())
+		enc.newline()
+		enc.eMapOrStruct(key, trv)
+	}
+}
+
+func (enc *Encoder) eTable(key Key, rv reflect.Value) {
+	panicIfInvalidKey(key)
+	if len(key) == 1 {
+		// Output an extra new line between top-level tables.
+		// (The newline isn't written if nothing else has been written though.)
+		enc.newline()
+	}
+	if len(key) > 0 {
+		enc.wf("%s[%s]", enc.indentStr(key), key.maybeQuotedAll())
+		enc.newline()
+	}
+	enc.eMapOrStruct(key, rv)
+}
+
+func (enc *Encoder) eMapOrStruct(key Key, rv reflect.Value) {
+	switch rv := eindirect(rv); rv.Kind() {
+	case reflect.Map:
+		enc.eMap(key, rv)
+	case reflect.Struct:
+		enc.eStruct(key, rv)
+	default:
+		panic("eTable: unhandled reflect.Value Kind: " + rv.Kind().String())
+	}
+}
+
+func (enc *Encoder) eMap(key Key, rv reflect.Value) {
+	rt := rv.Type()
+	if rt.Key().Kind() != reflect.String {
+		encPanic(errNonString)
+	}
+
+	// Sort keys so that we have deterministic output. And write keys directly
+	// underneath this key first, before writing sub-structs or sub-maps.
+	var mapKeysDirect, mapKeysSub []string
+	for _, mapKey := range rv.MapKeys() {
+		k := mapKey.String()
+		if typeIsHash(tomlTypeOfGo(rv.MapIndex(mapKey))) {
+			mapKeysSub = append(mapKeysSub, k)
+		} else {
+			mapKeysDirect = append(mapKeysDirect, k)
+		}
+	}
+
+	var writeMapKeys = func(mapKeys []string) {
+		sort.Strings(mapKeys)
+		for _, mapKey := range mapKeys {
+			mrv := rv.MapIndex(reflect.ValueOf(mapKey))
+			if isNil(mrv) {
+				// Don't write anything for nil fields.
+				continue
+			}
+			enc.encode(key.add(mapKey), mrv)
+		}
+	}
+	writeMapKeys(mapKeysDirect)
+	writeMapKeys(mapKeysSub)
+}
+
+func (enc *Encoder) eStruct(key Key, rv reflect.Value) {
+	// Write keys for fields directly under this key first, because if we write
+	// a field that creates a new table, then all keys under it will be in that
+	// table (not the one we're writing here).
+	rt := rv.Type()
+	var fieldsDirect, fieldsSub [][]int
+	var addFields func(rt reflect.Type, rv reflect.Value, start []int)
+	addFields = func(rt reflect.Type, rv reflect.Value, start []int) {
+		for i := 0; i < rt.NumField(); i++ {
+			f := rt.Field(i)
+			// skip unexported fields
+			if f.PkgPath != "" && !f.Anonymous {
+				continue
+			}
+			frv := rv.Field(i)
+			if f.Anonymous {
+				t := f.Type
+				switch t.Kind() {
+				case reflect.Struct:
+					// Treat anonymous struct fields with
+					// tag names as though they are not
+					// anonymous, like encoding/json does.
+					if getOptions(f.Tag).name == "" {
+						addFields(t, frv, f.Index)
+						continue
+					}
+				case reflect.Ptr:
+					if t.Elem().Kind() == reflect.Struct &&
+						getOptions(f.Tag).name == "" {
+						if !frv.IsNil() {
+							addFields(t.Elem(), frv.Elem(), f.Index)
+						}
+						continue
+					}
+					// Fall through to the normal field encoding logic below
+					// for non-struct anonymous fields.
+				}
+			}
+
+			if typeIsHash(tomlTypeOfGo(frv)) {
+				fieldsSub = append(fieldsSub, append(start, f.Index...)<