mirror of
https://github.com/octoleo/syncthing.git
synced 2024-12-31 05:51:50 +00:00
This changes the TLS and certificate handling in a few ways: - We always use TLS 1.2, both for sync connections (as previously) and the GUI/REST/discovery stuff. This is a tightening of the requirements on the GUI. AS far as I can tell from caniusethis.com every browser from 2013 and forward supports TLS 1.2, so I think we should be fine. - We always greate ECDSA certificates. Previously we'd create ECDSA-with-RSA certificates for sync connections and pure RSA certificates for the web stuff. The new default is more modern and the same everywhere. These certificates are OK in TLS 1.2. - We use the Go CPU detection stuff to choose the cipher suites to use, indirectly. The TLS package uses CPU capabilities probing to select either AES-GCM (fast if we have AES-NI) or ChaCha20 (faster if we don't). These CPU detection things aren't exported though, so the tlsutil package now does a quick TLS handshake with itself as part of init(). If the chosen cipher suite was AES-GCM we prioritize that, otherwise we prefer ChaCha20. Some might call this ugly. I think it's awesome.
This commit is contained in:
Jakob Borg
GitHub
parent
c0be9987d0
commit
8519a24ba6
@ -121,7 +121,7 @@ func main() {
|
||||
cert, err := tls.LoadX509KeyPair(certFile, keyFile)
|
||||
if err != nil {
|
||||
log.Println("Failed to load keypair. Generating one, this might take a while...")
|
||||
cert, err = tlsutil.NewCertificate(certFile, keyFile, "stdiscosrv", 0)
|
||||
cert, err = tlsutil.NewCertificate(certFile, keyFile, "stdiscosrv")
|
||||
if err != nil {
|
||||
log.Fatalln("Failed to generate X509 key pair:", err)
|
||||
}
|
||||
|
||||
@ -636,7 +636,7 @@ func createTestCertificate() tls.Certificate {
|
||||
}
|
||||
|
||||
certFile, keyFile := filepath.Join(tmpDir, "cert.pem"), filepath.Join(tmpDir, "key.pem")
|
||||
cert, err := tlsutil.NewCertificate(certFile, keyFile, "relaypoolsrv", 3072)
|
||||
cert, err := tlsutil.NewCertificate(certFile, keyFile, "relaypoolsrv")
|
||||
if err != nil {
|
||||
log.Fatalln("Failed to create test X509 key pair:", err)
|
||||
}
|
||||
|
||||
@ -166,7 +166,7 @@ func main() {
|
||||
cert, err := tls.LoadX509KeyPair(certFile, keyFile)
|
||||
if err != nil {
|
||||
log.Println("Failed to load keypair. Generating one, this might take a while...")
|
||||
cert, err = tlsutil.NewCertificate(certFile, keyFile, "strelaysrv", 3072)
|
||||
cert, err = tlsutil.NewCertificate(certFile, keyFile, "strelaysrv")
|
||||
if err != nil {
|
||||
log.Fatalln("Failed to generate X509 key pair:", err)
|
||||
}
|
||||
|
||||
@ -185,28 +185,13 @@ func (s *apiService) getListener(guiCfg config.GUIConfiguration) (net.Listener,
|
||||
name = tlsDefaultCommonName
|
||||
}
|
||||
|
||||
cert, err = tlsutil.NewCertificate(s.httpsCertFile, s.httpsKeyFile, name, httpsRSABits)
|
||||
cert, err = tlsutil.NewCertificate(s.httpsCertFile, s.httpsKeyFile, name)
|
||||
}
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
tlsCfg := &tls.Config{
|
||||
Certificates: []tls.Certificate{cert},
|
||||
MinVersion: tls.VersionTLS10, // No SSLv3
|
||||
CipherSuites: []uint16{
|
||||
// No RC4
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_3DES_EDE_CBC_SHA,
|
||||
},
|
||||
}
|
||||
tlsCfg := tlsutil.SecureDefault()
|
||||
tlsCfg.Certificates = []tls.Certificate{cert}
|
||||
|
||||
if guiCfg.Network() == "unix" {
|
||||
// When listening on a UNIX socket we should unlink before bind,
|
||||
|
||||
@ -78,8 +78,6 @@ const (
|
||||
const (
|
||||
bepProtocolName = "bep/1.0"
|
||||
tlsDefaultCommonName = "syncthing"
|
||||
httpsRSABits = 2048
|
||||
bepRSABits = 0 // 384 bit ECDSA used instead
|
||||
defaultEventTimeout = time.Minute
|
||||
maxSystemErrors = 5
|
||||
initialSystemLog = 10
|
||||
@ -471,7 +469,7 @@ func generate(generateDir string) {
|
||||
l.Warnln("Key exists; will not overwrite.")
|
||||
l.Infoln("Device ID:", protocol.NewDeviceID(cert.Certificate[0]))
|
||||
} else {
|
||||
cert, err = tlsutil.NewCertificate(certFile, keyFile, tlsDefaultCommonName, bepRSABits)
|
||||
cert, err = tlsutil.NewCertificate(certFile, keyFile, tlsDefaultCommonName)
|
||||
if err != nil {
|
||||
l.Fatalln("Create certificate:", err)
|
||||
}
|
||||
@ -639,7 +637,7 @@ func syncthingMain(runtimeOptions RuntimeOptions) {
|
||||
cert, err := tls.LoadX509KeyPair(locations[locCertFile], locations[locKeyFile])
|
||||
if err != nil {
|
||||
l.Infof("Generating ECDSA key and certificate for %s...", tlsDefaultCommonName)
|
||||
cert, err = tlsutil.NewCertificate(locations[locCertFile], locations[locKeyFile], tlsDefaultCommonName, bepRSABits)
|
||||
cert, err = tlsutil.NewCertificate(locations[locCertFile], locations[locKeyFile], tlsDefaultCommonName)
|
||||
if err != nil {
|
||||
l.Fatalln(err)
|
||||
}
|
||||
@ -680,30 +678,6 @@ func syncthingMain(runtimeOptions RuntimeOptions) {
|
||||
}()
|
||||
}
|
||||
|
||||
// The TLS configuration is used for both the listening socket and outgoing
|
||||
// connections.
|
||||
|
||||
tlsCfg := &tls.Config{
|
||||
Certificates: []tls.Certificate{cert},
|
||||
NextProtos: []string{bepProtocolName},
|
||||
ClientAuth: tls.RequestClientCert,
|
||||
SessionTicketsDisabled: true,
|
||||
InsecureSkipVerify: true,
|
||||
MinVersion: tls.VersionTLS12,
|
||||
CipherSuites: []uint16{
|
||||
tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
|
||||
},
|
||||
}
|
||||
|
||||
perf := cpuBench(3, 150*time.Millisecond, true)
|
||||
l.Infof("Hashing performance is %.02f MB/s", perf)
|
||||
|
||||
@ -794,6 +768,16 @@ func syncthingMain(runtimeOptions RuntimeOptions) {
|
||||
cachedDiscovery := discover.NewCachingMux()
|
||||
mainService.Add(cachedDiscovery)
|
||||
|
||||
// The TLS configuration is used for both the listening socket and outgoing
|
||||
// connections.
|
||||
|
||||
tlsCfg := tlsutil.SecureDefault()
|
||||
tlsCfg.Certificates = []tls.Certificate{cert}
|
||||
tlsCfg.NextProtos = []string{bepProtocolName}
|
||||
tlsCfg.ClientAuth = tls.RequestClientCert
|
||||
tlsCfg.SessionTicketsDisabled = true
|
||||
tlsCfg.InsecureSkipVerify = true
|
||||
|
||||
// Start connection management
|
||||
|
||||
connectionsService := connections.NewService(cfg, myID, m, tlsCfg, cachedDiscovery, bepProtocolName, tlsDefaultCommonName)
|
||||
|
||||
@ -110,9 +110,8 @@ func TestGlobalOverHTTPS(t *testing.T) {
|
||||
t.Fatal(err)
|
||||
}
|
||||
|
||||
// Generate a server certificate, using fewer bits than usual to hurry the
|
||||
// process along a bit.
|
||||
cert, err := tlsutil.NewCertificate(dir+"/cert.pem", dir+"/key.pem", "syncthing", 1024)
|
||||
// Generate a server certificate.
|
||||
cert, err := tlsutil.NewCertificate(dir+"/cert.pem", dir+"/key.pem", "syncthing")
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
@ -176,9 +175,8 @@ func TestGlobalAnnounce(t *testing.T) {
|
||||
t.Fatal(err)
|
||||
}
|
||||
|
||||
// Generate a server certificate, using fewer bits than usual to hurry the
|
||||
// process along a bit.
|
||||
cert, err := tlsutil.NewCertificate(dir+"/cert.pem", dir+"/key.pem", "syncthing", 1024)
|
||||
// Generate a server certificate.
|
||||
cert, err := tlsutil.NewCertificate(dir+"/cert.pem", dir+"/key.pem", "syncthing")
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
|
||||
@ -27,17 +27,74 @@ var (
|
||||
ErrIdentificationFailed = fmt.Errorf("failed to identify socket type")
|
||||
)
|
||||
|
||||
// NewCertificate generates and returns a new TLS certificate. If tlsRSABits
|
||||
// is greater than zero we generate an RSA certificate with the specified
|
||||
// number of bits. Otherwise we create a 384 bit ECDSA certificate.
|
||||
func NewCertificate(certFile, keyFile, tlsDefaultCommonName string, tlsRSABits int) (tls.Certificate, error) {
|
||||
var priv interface{}
|
||||
var err error
|
||||
if tlsRSABits > 0 {
|
||||
priv, err = rsa.GenerateKey(rand.Reader, tlsRSABits)
|
||||
} else {
|
||||
priv, err = ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
|
||||
var (
|
||||
// The list of cipher suites we will use / suggest for TLS connections.
|
||||
// This is built based on the component slices below, depending on what
|
||||
// the hardware prefers.
|
||||
cipherSuites []uint16
|
||||
|
||||
// Suites that are good and fast on hardware with AES-NI. These are
|
||||
// reordered from the Go default to put the 256 bit ciphers above the
|
||||
// 128 bit ones - because that looks cooler, even though there is
|
||||
// probably no relevant difference in strength yet.
|
||||
gcmSuites = []uint16{
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
|
||||
}
|
||||
|
||||
// Suites that are good and fast on hardware *without* AES-NI.
|
||||
chaChaSuites = []uint16{
|
||||
tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
|
||||
}
|
||||
|
||||
// The rest of the suites, minus DES stuff.
|
||||
otherSuites = []uint16{
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
|
||||
tls.TLS_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_AES_256_CBC_SHA,
|
||||
}
|
||||
)
|
||||
|
||||
func init() {
|
||||
// Creates the list of ciper suites that SecureDefault uses.
|
||||
cipherSuites = buildCipherSuites()
|
||||
}
|
||||
|
||||
// SecureDefault returns a tls.Config with reasonable, secure defaults set.
|
||||
func SecureDefault() *tls.Config {
|
||||
// paranoia
|
||||
cs := make([]uint16, len(cipherSuites))
|
||||
copy(cs, cipherSuites)
|
||||
|
||||
return &tls.Config{
|
||||
// TLS 1.2 is the minimum we accept
|
||||
MinVersion: tls.VersionTLS12,
|
||||
// We want the longer curves at the front, because that's more
|
||||
// secure (so the web tells me, don't ask me to explain the
|
||||
// details).
|
||||
CurvePreferences: []tls.CurveID{tls.CurveP521, tls.CurveP384, tls.CurveP256},
|
||||
// The cipher suite lists built above.
|
||||
CipherSuites: cs,
|
||||
// We've put some thought into this choice and would like it to
|
||||
// matter.
|
||||
PreferServerCipherSuites: true,
|
||||
}
|
||||
}
|
||||
|
||||
// NewCertificate generates and returns a new TLS certificate.
|
||||
func NewCertificate(certFile, keyFile, commonName string) (tls.Certificate, error) {
|
||||
priv, err := ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
|
||||
if err != nil {
|
||||
return tls.Certificate{}, fmt.Errorf("generate key: %s", err)
|
||||
}
|
||||
@ -48,11 +105,11 @@ func NewCertificate(certFile, keyFile, tlsDefaultCommonName string, tlsRSABits i
|
||||
template := x509.Certificate{
|
||||
SerialNumber: new(big.Int).SetInt64(rand.Int63()),
|
||||
Subject: pkix.Name{
|
||||
CommonName: tlsDefaultCommonName,
|
||||
CommonName: commonName,
|
||||
},
|
||||
NotBefore: notBefore,
|
||||
NotAfter: notAfter,
|
||||
|
||||
NotBefore: notBefore,
|
||||
NotAfter: notAfter,
|
||||
SignatureAlgorithm: x509.ECDSAWithSHA256,
|
||||
KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
|
||||
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth, x509.ExtKeyUsageClientAuth},
|
||||
BasicConstraintsValid: true,
|
||||
@ -185,3 +242,79 @@ func pemBlockForKey(priv interface{}) (*pem.Block, error) {
|
||||
return nil, fmt.Errorf("unknown key type")
|
||||
}
|
||||
}
|
||||
|
||||
// buildCipherSuites returns a list of cipher suites with either AES-GCM or
|
||||
// ChaCha20 at the top. This takes advantage of the CPU detection that the
|
||||
// TLS package does to create an optimal cipher suite list for the current
|
||||
// hardware.
|
||||
func buildCipherSuites() []uint16 {
|
||||
pref := preferredCipherSuite()
|
||||
for _, suite := range gcmSuites {
|
||||
if suite == pref {
|
||||
// Go preferred an AES-GCM suite. Use those first.
|
||||
return append(gcmSuites, append(chaChaSuites, otherSuites...)...)
|
||||
}
|
||||
}
|
||||
// Use ChaCha20 at the top, then AES-GCM etc.
|
||||
return append(chaChaSuites, append(gcmSuites, otherSuites...)...)
|
||||
}
|
||||
|
||||
// preferredCipherSuite returns the cipher suite that is selected for a TLS
|
||||
// connection made with the Go defaults to ourselves. This is (currently,
|
||||
// probably) either a ChaCha20 suite or an AES-GCM suite, depending on what
|
||||
// the CPU detection has decided is fastest on this hardware.
|
||||
//
|
||||
// The function will return zero if something odd happens, and there's no
|
||||
// guarantee what cipher suite would be chosen anyway, so the return value
|
||||
// should be taken with a grain of salt.
|
||||
func preferredCipherSuite() uint16 {
|
||||
// This is one of our certs from NewCertificate above, to avoid having
|
||||
// to generate one at init time just for this function.
|
||||
crtBs := []byte(`-----BEGIN CERTIFICATE-----
|
||||
MIIBXDCCAQOgAwIBAgIIQUODl2/bE4owCgYIKoZIzj0EAwIwFDESMBAGA1UEAxMJ
|
||||
c3luY3RoaW5nMB4XDTE4MTAxNDA2MjU0M1oXDTQ5MTIzMTIzNTk1OVowFDESMBAG
|
||||
A1UEAxMJc3luY3RoaW5nMFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEMqP+1lL4
|
||||
0s/xtI3ygExzYc/GvLHr0qetpBrUVHaDwS/cR1yXDsYaJpJcUNtrf1XK49IlpWW1
|
||||
Ds8seQsSg7/9BaM/MD0wDgYDVR0PAQH/BAQDAgWgMB0GA1UdJQQWMBQGCCsGAQUF
|
||||
BwMBBggrBgEFBQcDAjAMBgNVHRMBAf8EAjAAMAoGCCqGSM49BAMCA0cAMEQCIFxY
|
||||
MDBA92FKqZYSZjmfdIbT1OI6S9CnAFvL/pJZJwNuAiAV7osre2NiCHtXABOvsGrH
|
||||
vKWqDvXcHr6Tlo+LmTAdyg==
|
||||
-----END CERTIFICATE-----
|
||||
`)
|
||||
keyBs := []byte(`-----BEGIN EC PRIVATE KEY-----
|
||||
MHcCAQEEIHtPxVHlj6Bhi9RgSR2/lAtIQ7APM9wmpaJAcds6TD2CoAoGCCqGSM49
|
||||
AwEHoUQDQgAEMqP+1lL40s/xtI3ygExzYc/GvLHr0qetpBrUVHaDwS/cR1yXDsYa
|
||||
JpJcUNtrf1XK49IlpWW1Ds8seQsSg7/9BQ==
|
||||
-----END EC PRIVATE KEY-----
|
||||
`)
|
||||
|
||||
cert, err := tls.X509KeyPair(crtBs, keyBs)
|
||||
if err != nil {
|
||||
return 0
|
||||
}
|
||||
|
||||
serverCfg := &tls.Config{
|
||||
MinVersion: tls.VersionTLS12,
|
||||
PreferServerCipherSuites: true,
|
||||
Certificates: []tls.Certificate{cert},
|
||||
}
|
||||
|
||||
clientCfg := &tls.Config{
|
||||
MinVersion: tls.VersionTLS12,
|
||||
InsecureSkipVerify: true,
|
||||
}
|
||||
|
||||
c0, c1 := net.Pipe()
|
||||
|
||||
c := tls.Client(c0, clientCfg)
|
||||
go func() {
|
||||
c.Handshake()
|
||||
}()
|
||||
|
||||
s := tls.Server(c1, serverCfg)
|
||||
if err := s.Handshake(); err != nil {
|
||||
return 0
|
||||
}
|
||||
|
||||
return c.ConnectionState().CipherSuite
|
||||
}
|
||||
|
||||
@ -11,6 +11,7 @@ package tlsutil
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"crypto/tls"
|
||||
"io"
|
||||
"net"
|
||||
"testing"
|
||||
@ -74,6 +75,53 @@ func TestUnionedConnection(t *testing.T) {
|
||||
}
|
||||
}
|
||||
|
||||
func TestCheckCipherSuites(t *testing.T) {
|
||||
// This is the set of cipher suites we expect - only the order should
|
||||
// differ.
|
||||
allSuites := []uint16{
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_AES_128_GCM_SHA256,
|
||||
tls.TLS_RSA_WITH_AES_256_GCM_SHA384,
|
||||
tls.TLS_RSA_WITH_AES_128_CBC_SHA256,
|
||||
tls.TLS_RSA_WITH_AES_128_CBC_SHA,
|
||||
tls.TLS_RSA_WITH_AES_256_CBC_SHA,
|
||||
}
|
||||
|
||||
suites := buildCipherSuites()
|
||||
|
||||
if len(suites) != len(allSuites) {
|
||||
t.Fatal("should get a list representing all suites")
|
||||
}
|
||||
|
||||
// Check that the returned list of suites doesn't contain anything
|
||||
// unexpecteds and is free from duplicates.
|
||||
seen := make(map[uint16]struct{})
|
||||
nextSuite:
|
||||
for _, s0 := range suites {
|
||||
if _, ok := seen[s0]; ok {
|
||||
t.Fatal("duplicate suite", s0)
|
||||
}
|
||||
for _, s1 := range allSuites {
|
||||
if s0 == s1 {
|
||||
seen[s0] = struct{}{}
|
||||
continue nextSuite
|
||||
}
|
||||
}
|
||||
t.Fatal("got unknown suite", s0)
|
||||
}
|
||||
}
|
||||
|
||||
type fakeAccepter struct {
|
||||
data []byte
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user