545 lines
18 KiB
Go
545 lines
18 KiB
Go
// Copyright 2017 The go-ethereum Authors
|
|
// This file is part of go-ethereum.
|
|
//
|
|
// go-ethereum is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// go-ethereum is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
// faucet is a Ether faucet backed by a light client.
|
|
package main
|
|
|
|
//go:generate go-bindata -nometadata -o website.go faucet.html
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"encoding/json"
|
|
"flag"
|
|
"fmt"
|
|
"html/template"
|
|
"io/ioutil"
|
|
"math"
|
|
"math/big"
|
|
"net/http"
|
|
"net/url"
|
|
"os"
|
|
"path/filepath"
|
|
"strconv"
|
|
"strings"
|
|
"sync"
|
|
"time"
|
|
|
|
"github.com/ethereum/go-ethereum/accounts"
|
|
"github.com/ethereum/go-ethereum/accounts/keystore"
|
|
"github.com/ethereum/go-ethereum/common"
|
|
"github.com/ethereum/go-ethereum/core"
|
|
"github.com/ethereum/go-ethereum/core/types"
|
|
"github.com/ethereum/go-ethereum/eth"
|
|
"github.com/ethereum/go-ethereum/eth/downloader"
|
|
"github.com/ethereum/go-ethereum/ethclient"
|
|
"github.com/ethereum/go-ethereum/ethstats"
|
|
"github.com/ethereum/go-ethereum/les"
|
|
"github.com/ethereum/go-ethereum/log"
|
|
"github.com/ethereum/go-ethereum/node"
|
|
"github.com/ethereum/go-ethereum/p2p"
|
|
"github.com/ethereum/go-ethereum/p2p/discover"
|
|
"github.com/ethereum/go-ethereum/p2p/discv5"
|
|
"github.com/ethereum/go-ethereum/p2p/nat"
|
|
"github.com/ethereum/go-ethereum/params"
|
|
"golang.org/x/net/websocket"
|
|
)
|
|
|
|
var (
|
|
genesisFlag = flag.String("genesis", "", "Genesis json file to seed the chain with")
|
|
apiPortFlag = flag.Int("apiport", 8080, "Listener port for the HTTP API connection")
|
|
ethPortFlag = flag.Int("ethport", 30303, "Listener port for the devp2p connection")
|
|
bootFlag = flag.String("bootnodes", "", "Comma separated bootnode enode URLs to seed with")
|
|
netFlag = flag.Uint64("network", 0, "Network ID to use for the Ethereum protocol")
|
|
statsFlag = flag.String("ethstats", "", "Ethstats network monitoring auth string")
|
|
|
|
netnameFlag = flag.String("faucet.name", "", "Network name to assign to the faucet")
|
|
payoutFlag = flag.Int("faucet.amount", 1, "Number of Ethers to pay out per user request")
|
|
minutesFlag = flag.Int("faucet.minutes", 1440, "Number of minutes to wait between funding rounds")
|
|
tiersFlag = flag.Int("faucet.tiers", 3, "Number of funding tiers to enable (x3 time, x2.5 funds)")
|
|
|
|
accJSONFlag = flag.String("account.json", "", "Key json file to fund user requests with")
|
|
accPassFlag = flag.String("account.pass", "", "Decryption password to access faucet funds")
|
|
|
|
githubUser = flag.String("github.user", "", "GitHub user to authenticate with for Gist access")
|
|
githubToken = flag.String("github.token", "", "GitHub personal token to access Gists with")
|
|
|
|
captchaToken = flag.String("captcha.token", "", "Recaptcha site key to authenticate client side")
|
|
captchaSecret = flag.String("captcha.secret", "", "Recaptcha secret key to authenticate server side")
|
|
|
|
logFlag = flag.Int("loglevel", 3, "Log level to use for Ethereum and the faucet")
|
|
)
|
|
|
|
var (
|
|
ether = new(big.Int).Exp(big.NewInt(10), big.NewInt(18), nil)
|
|
)
|
|
|
|
func main() {
|
|
// Parse the flags and set up the logger to print everything requested
|
|
flag.Parse()
|
|
log.Root().SetHandler(log.LvlFilterHandler(log.Lvl(*logFlag), log.StreamHandler(os.Stderr, log.TerminalFormat(true))))
|
|
|
|
// Construct the payout tiers
|
|
amounts := make([]string, *tiersFlag)
|
|
periods := make([]string, *tiersFlag)
|
|
for i := 0; i < *tiersFlag; i++ {
|
|
// Calculate the amount for the next tier and format it
|
|
amount := float64(*payoutFlag) * math.Pow(2.5, float64(i))
|
|
amounts[i] = fmt.Sprintf("%s Ethers", strconv.FormatFloat(amount, 'f', -1, 64))
|
|
if amount == 1 {
|
|
amounts[i] = strings.TrimSuffix(amounts[i], "s")
|
|
}
|
|
// Calculate the period for the next tier and format it
|
|
period := *minutesFlag * int(math.Pow(3, float64(i)))
|
|
periods[i] = fmt.Sprintf("%d mins", period)
|
|
if period%60 == 0 {
|
|
period /= 60
|
|
periods[i] = fmt.Sprintf("%d hours", period)
|
|
|
|
if period%24 == 0 {
|
|
period /= 24
|
|
periods[i] = fmt.Sprintf("%d days", period)
|
|
}
|
|
}
|
|
if period == 1 {
|
|
periods[i] = strings.TrimSuffix(periods[i], "s")
|
|
}
|
|
}
|
|
// Load up and render the faucet website
|
|
tmpl, err := Asset("faucet.html")
|
|
if err != nil {
|
|
log.Crit("Failed to load the faucet template", "err", err)
|
|
}
|
|
website := new(bytes.Buffer)
|
|
err = template.Must(template.New("").Parse(string(tmpl))).Execute(website, map[string]interface{}{
|
|
"Network": *netnameFlag,
|
|
"Amounts": amounts,
|
|
"Periods": periods,
|
|
"Recaptcha": *captchaToken,
|
|
})
|
|
if err != nil {
|
|
log.Crit("Failed to render the faucet template", "err", err)
|
|
}
|
|
// Load and parse the genesis block requested by the user
|
|
blob, err := ioutil.ReadFile(*genesisFlag)
|
|
if err != nil {
|
|
log.Crit("Failed to read genesis block contents", "genesis", *genesisFlag, "err", err)
|
|
}
|
|
genesis := new(core.Genesis)
|
|
if err = json.Unmarshal(blob, genesis); err != nil {
|
|
log.Crit("Failed to parse genesis block json", "err", err)
|
|
}
|
|
// Convert the bootnodes to internal enode representations
|
|
var enodes []*discv5.Node
|
|
for _, boot := range strings.Split(*bootFlag, ",") {
|
|
if url, err := discv5.ParseNode(boot); err == nil {
|
|
enodes = append(enodes, url)
|
|
} else {
|
|
log.Error("Failed to parse bootnode URL", "url", boot, "err", err)
|
|
}
|
|
}
|
|
// Load up the account key and decrypt its password
|
|
if blob, err = ioutil.ReadFile(*accPassFlag); err != nil {
|
|
log.Crit("Failed to read account password contents", "file", *accPassFlag, "err", err)
|
|
}
|
|
pass := string(blob)
|
|
|
|
ks := keystore.NewKeyStore(filepath.Join(os.Getenv("HOME"), ".faucet", "keys"), keystore.StandardScryptN, keystore.StandardScryptP)
|
|
if blob, err = ioutil.ReadFile(*accJSONFlag); err != nil {
|
|
log.Crit("Failed to read account key contents", "file", *accJSONFlag, "err", err)
|
|
}
|
|
acc, err := ks.Import(blob, pass, pass)
|
|
if err != nil {
|
|
log.Crit("Failed to import faucet signer account", "err", err)
|
|
}
|
|
ks.Unlock(acc, pass)
|
|
|
|
// Assemble and start the faucet light service
|
|
faucet, err := newFaucet(genesis, *ethPortFlag, enodes, *netFlag, *statsFlag, ks, website.Bytes())
|
|
if err != nil {
|
|
log.Crit("Failed to start faucet", "err", err)
|
|
}
|
|
defer faucet.close()
|
|
|
|
if err := faucet.listenAndServe(*apiPortFlag); err != nil {
|
|
log.Crit("Failed to launch faucet API", "err", err)
|
|
}
|
|
}
|
|
|
|
// request represents an accepted funding request.
|
|
type request struct {
|
|
Username string `json:"username"` // GitHub user for displaying an avatar
|
|
Account common.Address `json:"account"` // Ethereum address being funded
|
|
Time time.Time `json:"time"` // Timestamp when te request was accepted
|
|
Tx *types.Transaction `json:"tx"` // Transaction funding the account
|
|
}
|
|
|
|
// faucet represents a crypto faucet backed by an Ethereum light client.
|
|
type faucet struct {
|
|
config *params.ChainConfig // Chain configurations for signing
|
|
stack *node.Node // Ethereum protocol stack
|
|
client *ethclient.Client // Client connection to the Ethereum chain
|
|
index []byte // Index page to serve up on the web
|
|
|
|
keystore *keystore.KeyStore // Keystore containing the single signer
|
|
account accounts.Account // Account funding user faucet requests
|
|
nonce uint64 // Current pending nonce of the faucet
|
|
price *big.Int // Current gas price to issue funds with
|
|
|
|
conns []*websocket.Conn // Currently live websocket connections
|
|
timeouts map[string]time.Time // History of users and their funding timeouts
|
|
reqs []*request // Currently pending funding requests
|
|
update chan struct{} // Channel to signal request updates
|
|
|
|
lock sync.RWMutex // Lock protecting the faucet's internals
|
|
}
|
|
|
|
func newFaucet(genesis *core.Genesis, port int, enodes []*discv5.Node, network uint64, stats string, ks *keystore.KeyStore, index []byte) (*faucet, error) {
|
|
// Assemble the raw devp2p protocol stack
|
|
stack, err := node.New(&node.Config{
|
|
Name: "geth",
|
|
Version: params.Version,
|
|
DataDir: filepath.Join(os.Getenv("HOME"), ".faucet"),
|
|
P2P: p2p.Config{
|
|
NAT: nat.Any(),
|
|
NoDiscovery: true,
|
|
DiscoveryV5: true,
|
|
ListenAddr: fmt.Sprintf(":%d", port),
|
|
DiscoveryV5Addr: fmt.Sprintf(":%d", port+1),
|
|
MaxPeers: 25,
|
|
BootstrapNodesV5: enodes,
|
|
},
|
|
})
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
// Assemble the Ethereum light client protocol
|
|
if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
|
|
cfg := eth.DefaultConfig
|
|
cfg.SyncMode = downloader.LightSync
|
|
cfg.NetworkId = network
|
|
cfg.Genesis = genesis
|
|
return les.New(ctx, &cfg)
|
|
}); err != nil {
|
|
return nil, err
|
|
}
|
|
// Assemble the ethstats monitoring and reporting service'
|
|
if stats != "" {
|
|
if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
|
|
var serv *les.LightEthereum
|
|
ctx.Service(&serv)
|
|
return ethstats.New(stats, nil, serv)
|
|
}); err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
// Boot up the client and ensure it connects to bootnodes
|
|
if err := stack.Start(); err != nil {
|
|
return nil, err
|
|
}
|
|
for _, boot := range enodes {
|
|
old, _ := discover.ParseNode(boot.String())
|
|
stack.Server().AddPeer(old)
|
|
}
|
|
// Attach to the client and retrieve and interesting metadatas
|
|
api, err := stack.Attach()
|
|
if err != nil {
|
|
stack.Stop()
|
|
return nil, err
|
|
}
|
|
client := ethclient.NewClient(api)
|
|
|
|
return &faucet{
|
|
config: genesis.Config,
|
|
stack: stack,
|
|
client: client,
|
|
index: index,
|
|
keystore: ks,
|
|
account: ks.Accounts()[0],
|
|
timeouts: make(map[string]time.Time),
|
|
update: make(chan struct{}, 1),
|
|
}, nil
|
|
}
|
|
|
|
// close terminates the Ethereum connection and tears down the faucet.
|
|
func (f *faucet) close() error {
|
|
return f.stack.Stop()
|
|
}
|
|
|
|
// listenAndServe registers the HTTP handlers for the faucet and boots it up
|
|
// for service user funding requests.
|
|
func (f *faucet) listenAndServe(port int) error {
|
|
go f.loop()
|
|
|
|
http.HandleFunc("/", f.webHandler)
|
|
http.Handle("/api", websocket.Handler(f.apiHandler))
|
|
|
|
return http.ListenAndServe(fmt.Sprintf(":%d", port), nil)
|
|
}
|
|
|
|
// webHandler handles all non-api requests, simply flattening and returning the
|
|
// faucet website.
|
|
func (f *faucet) webHandler(w http.ResponseWriter, r *http.Request) {
|
|
w.Write(f.index)
|
|
}
|
|
|
|
// apiHandler handles requests for Ether grants and transaction statuses.
|
|
func (f *faucet) apiHandler(conn *websocket.Conn) {
|
|
// Start tracking the connection and drop at the end
|
|
f.lock.Lock()
|
|
f.conns = append(f.conns, conn)
|
|
f.lock.Unlock()
|
|
|
|
defer func() {
|
|
f.lock.Lock()
|
|
for i, c := range f.conns {
|
|
if c == conn {
|
|
f.conns = append(f.conns[:i], f.conns[i+1:]...)
|
|
break
|
|
}
|
|
}
|
|
f.lock.Unlock()
|
|
}()
|
|
// Send a few initial stats to the client
|
|
balance, _ := f.client.BalanceAt(context.Background(), f.account.Address, nil)
|
|
nonce, _ := f.client.NonceAt(context.Background(), f.account.Address, nil)
|
|
|
|
websocket.JSON.Send(conn, map[string]interface{}{
|
|
"funds": balance.Div(balance, ether),
|
|
"funded": nonce,
|
|
"peers": f.stack.Server().PeerCount(),
|
|
"requests": f.reqs,
|
|
})
|
|
// Send the initial block to the client
|
|
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
|
|
header, err := f.client.HeaderByNumber(ctx, nil)
|
|
cancel()
|
|
|
|
if err != nil {
|
|
log.Error("Failed to retrieve latest header", "err", err)
|
|
} else {
|
|
websocket.JSON.Send(conn, header)
|
|
}
|
|
// Keep reading requests from the websocket until the connection breaks
|
|
for {
|
|
// Fetch the next funding request and validate against github
|
|
var msg struct {
|
|
URL string `json:"url"`
|
|
Tier uint `json:"tier"`
|
|
Captcha string `json:"captcha"`
|
|
}
|
|
if err := websocket.JSON.Receive(conn, &msg); err != nil {
|
|
return
|
|
}
|
|
if !strings.HasPrefix(msg.URL, "https://gist.github.com/") {
|
|
websocket.JSON.Send(conn, map[string]string{"error": "URL doesn't link to GitHub Gists"})
|
|
continue
|
|
}
|
|
if msg.Tier >= uint(*tiersFlag) {
|
|
websocket.JSON.Send(conn, map[string]string{"error": "Invalid funding tier requested"})
|
|
continue
|
|
}
|
|
log.Info("Faucet funds requested", "gist", msg.URL, "tier", msg.Tier)
|
|
|
|
// If captcha verifications are enabled, make sure we're not dealing with a robot
|
|
if *captchaToken != "" {
|
|
form := url.Values{}
|
|
form.Add("secret", *captchaSecret)
|
|
form.Add("response", msg.Captcha)
|
|
|
|
res, err := http.PostForm("https://www.google.com/recaptcha/api/siteverify", form)
|
|
if err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
continue
|
|
}
|
|
var result struct {
|
|
Success bool `json:"success"`
|
|
Errors json.RawMessage `json:"error-codes"`
|
|
}
|
|
err = json.NewDecoder(res.Body).Decode(&result)
|
|
res.Body.Close()
|
|
if err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
continue
|
|
}
|
|
if !result.Success {
|
|
log.Warn("Captcha verification failed", "err", string(result.Errors))
|
|
websocket.JSON.Send(conn, map[string]string{"error": "Beep-bop, you're a robot!"})
|
|
continue
|
|
}
|
|
}
|
|
// Retrieve the gist from the GitHub Gist APIs
|
|
parts := strings.Split(msg.URL, "/")
|
|
req, _ := http.NewRequest("GET", "https://api.github.com/gists/"+parts[len(parts)-1], nil)
|
|
if *githubUser != "" {
|
|
req.SetBasicAuth(*githubUser, *githubToken)
|
|
}
|
|
res, err := http.DefaultClient.Do(req)
|
|
if err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
continue
|
|
}
|
|
var gist struct {
|
|
Owner struct {
|
|
Login string `json:"login"`
|
|
} `json:"owner"`
|
|
Files map[string]struct {
|
|
Content string `json:"content"`
|
|
} `json:"files"`
|
|
}
|
|
err = json.NewDecoder(res.Body).Decode(&gist)
|
|
res.Body.Close()
|
|
if err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
continue
|
|
}
|
|
if gist.Owner.Login == "" {
|
|
websocket.JSON.Send(conn, map[string]string{"error": "Anonymous Gists not allowed"})
|
|
continue
|
|
}
|
|
// Iterate over all the files and look for Ethereum addresses
|
|
var address common.Address
|
|
for _, file := range gist.Files {
|
|
content := strings.TrimSpace(file.Content)
|
|
if len(content) == 2+common.AddressLength*2 {
|
|
address = common.HexToAddress(content)
|
|
}
|
|
}
|
|
if address == (common.Address{}) {
|
|
websocket.JSON.Send(conn, map[string]string{"error": "No Ethereum address found to fund"})
|
|
continue
|
|
}
|
|
// Validate the user's existence since the API is unhelpful here
|
|
if res, err = http.Head("https://github.com/" + gist.Owner.Login); err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
continue
|
|
}
|
|
res.Body.Close()
|
|
|
|
if res.StatusCode != 200 {
|
|
websocket.JSON.Send(conn, map[string]string{"error": "Invalid user... boom!"})
|
|
continue
|
|
}
|
|
// Ensure the user didn't request funds too recently
|
|
f.lock.Lock()
|
|
var (
|
|
fund bool
|
|
timeout time.Time
|
|
)
|
|
if timeout = f.timeouts[gist.Owner.Login]; time.Now().After(timeout) {
|
|
// User wasn't funded recently, create the funding transaction
|
|
amount := new(big.Int).Mul(big.NewInt(int64(*payoutFlag)), ether)
|
|
amount = new(big.Int).Mul(amount, new(big.Int).Exp(big.NewInt(5), big.NewInt(int64(msg.Tier)), nil))
|
|
amount = new(big.Int).Div(amount, new(big.Int).Exp(big.NewInt(2), big.NewInt(int64(msg.Tier)), nil))
|
|
|
|
tx := types.NewTransaction(f.nonce+uint64(len(f.reqs)), address, amount, big.NewInt(21000), f.price, nil)
|
|
signed, err := f.keystore.SignTx(f.account, tx, f.config.ChainId)
|
|
if err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
f.lock.Unlock()
|
|
continue
|
|
}
|
|
// Submit the transaction and mark as funded if successful
|
|
if err := f.client.SendTransaction(context.Background(), signed); err != nil {
|
|
websocket.JSON.Send(conn, map[string]string{"error": err.Error()})
|
|
f.lock.Unlock()
|
|
continue
|
|
}
|
|
f.reqs = append(f.reqs, &request{
|
|
Username: gist.Owner.Login,
|
|
Account: address,
|
|
Time: time.Now(),
|
|
Tx: signed,
|
|
})
|
|
f.timeouts[gist.Owner.Login] = time.Now().Add(time.Duration(*minutesFlag*int(math.Pow(3, float64(msg.Tier)))) * time.Minute)
|
|
fund = true
|
|
}
|
|
f.lock.Unlock()
|
|
|
|
// Send an error if too frequent funding, othewise a success
|
|
if !fund {
|
|
websocket.JSON.Send(conn, map[string]string{"error": fmt.Sprintf("%s left until next allowance", common.PrettyDuration(timeout.Sub(time.Now())))})
|
|
continue
|
|
}
|
|
websocket.JSON.Send(conn, map[string]string{"success": fmt.Sprintf("Funding request accepted for %s into %s", gist.Owner.Login, address.Hex())})
|
|
select {
|
|
case f.update <- struct{}{}:
|
|
default:
|
|
}
|
|
}
|
|
}
|
|
|
|
// loop keeps waiting for interesting events and pushes them out to connected
|
|
// websockets.
|
|
func (f *faucet) loop() {
|
|
// Wait for chain events and push them to clients
|
|
heads := make(chan *types.Header, 16)
|
|
sub, err := f.client.SubscribeNewHead(context.Background(), heads)
|
|
if err != nil {
|
|
log.Crit("Failed to subscribe to head events", "err", err)
|
|
}
|
|
defer sub.Unsubscribe()
|
|
|
|
for {
|
|
select {
|
|
case head := <-heads:
|
|
// New chain head arrived, query the current stats and stream to clients
|
|
balance, _ := f.client.BalanceAt(context.Background(), f.account.Address, nil)
|
|
balance = new(big.Int).Div(balance, ether)
|
|
|
|
price, _ := f.client.SuggestGasPrice(context.Background())
|
|
nonce, _ := f.client.NonceAt(context.Background(), f.account.Address, nil)
|
|
|
|
f.lock.Lock()
|
|
f.price, f.nonce = price, nonce
|
|
for len(f.reqs) > 0 && f.reqs[0].Tx.Nonce() < f.nonce {
|
|
f.reqs = f.reqs[1:]
|
|
}
|
|
f.lock.Unlock()
|
|
|
|
f.lock.RLock()
|
|
for _, conn := range f.conns {
|
|
if err := websocket.JSON.Send(conn, map[string]interface{}{
|
|
"funds": balance,
|
|
"funded": f.nonce,
|
|
"peers": f.stack.Server().PeerCount(),
|
|
"requests": f.reqs,
|
|
}); err != nil {
|
|
log.Warn("Failed to send stats to client", "err", err)
|
|
conn.Close()
|
|
continue
|
|
}
|
|
if err := websocket.JSON.Send(conn, head); err != nil {
|
|
log.Warn("Failed to send header to client", "err", err)
|
|
conn.Close()
|
|
}
|
|
}
|
|
f.lock.RUnlock()
|
|
|
|
case <-f.update:
|
|
// Pending requests updated, stream to clients
|
|
f.lock.RLock()
|
|
for _, conn := range f.conns {
|
|
if err := websocket.JSON.Send(conn, map[string]interface{}{"requests": f.reqs}); err != nil {
|
|
log.Warn("Failed to send requests to client", "err", err)
|
|
conn.Close()
|
|
}
|
|
}
|
|
f.lock.RUnlock()
|
|
}
|
|
}
|
|
}
|