status-go/server/pairing/preflight/preflight.go

153 lines
3.0 KiB
Go

package preflight
import (
"crypto/tls"
"crypto/x509"
"fmt"
"net"
"net/http"
"net/url"
"strconv"
"sync"
"time"
"go.uber.org/zap"
"github.com/status-im/status-go/logutils"
"github.com/status-im/status-go/protocol/common"
"github.com/status-im/status-go/server"
)
const (
outboundCheck = "/outbound_check"
headerPing = "ping"
headerPong = "pong"
)
func preflightHandler(w http.ResponseWriter, r *http.Request) {
ping := r.Header.Get(headerPing)
if ping == "" {
http.Error(w, "no value in 'ping' header", http.StatusBadRequest)
}
w.Header().Set(headerPong, ping)
}
func makeCert(address net.IP) (*tls.Certificate, []byte, error) {
notBefore := time.Now()
notAfter := notBefore.Add(time.Minute)
return server.GenerateTLSCert(notBefore, notAfter, address.String())
}
func makeAndStartServer(cert *tls.Certificate, address net.IP) (string, func() error, error) {
wg := sync.WaitGroup{}
wg.Add(1)
waitForPortSet := func(int) {
wg.Done()
}
s := server.NewServer(
cert,
address.String(),
waitForPortSet,
logutils.ZapLogger().Named("Preflight Server"),
)
s.SetHandlers(server.HandlerPatternMap{outboundCheck: preflightHandler})
err := s.Start()
if err != nil {
return "", nil, err
}
wg.Wait()
return s.GetHostname() + ":" + strconv.Itoa(s.GetPort()), s.Stop, nil
}
func makeClient(certPem []byte) (*http.Client, error) {
rootCAs, err := x509.SystemCertPool()
if err != nil {
return nil, err
}
if ok := rootCAs.AppendCertsFromPEM(certPem); !ok {
return nil, fmt.Errorf("failed to append certPem to rootCAs")
}
tr := &http.Transport{
TLSClientConfig: &tls.Config{
MinVersion: tls.VersionTLS12,
InsecureSkipVerify: false, // MUST BE FALSE
RootCAs: rootCAs,
},
}
return &http.Client{Transport: tr}, nil
}
func makeOutboundCheck(c *http.Client, host string) error {
u := url.URL{
Scheme: "https",
Host: host,
Path: outboundCheck,
}
req, err := http.NewRequest("GET", u.String(), nil)
if err != nil {
return err
}
ping, err := common.RandomAlphanumericString(64)
if err != nil {
return err
}
req.Header.Set(headerPing, ping)
resp, err := c.Do(req)
if err != nil {
return err
}
if resp.StatusCode != http.StatusOK {
return fmt.Errorf("response status not ok, received '%d' : '%s'", resp.StatusCode, resp.Status)
}
pong := resp.Header.Get(headerPong)
if pong != ping {
return fmt.Errorf("ping should match pong: ping '%s', pong '%s'", ping, pong)
}
return nil
}
func CheckOutbound() error {
// cert stuff
outboundIP, err := server.GetOutboundIP()
if err != nil {
return err
}
cert, certPem, err := makeCert(outboundIP)
if err != nil {
return err
}
// server stuff
host, stop, err := makeAndStartServer(cert, outboundIP)
if err != nil {
return err
}
defer func() {
err := stop()
if err != nil {
logutils.ZapLogger().Error("error while stopping preflight serve", zap.Error(err))
}
}()
// Client stuff
c, err := makeClient(certPem)
if err != nil {
return err
}
return makeOutboundCheck(c, host)
}