github.com/megatontech/mynoteforgo@v0.0.0-20200507084910-5d0c6ea6e890/源码/crypto/tls/tls_test.go (about)

     1  // Copyright 2012 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package tls
     6  
     7  import (
     8  	"bytes"
     9  	"crypto/x509"
    10  	"encoding/json"
    11  	"errors"
    12  	"fmt"
    13  	"internal/testenv"
    14  	"io"
    15  	"io/ioutil"
    16  	"math"
    17  	"net"
    18  	"os"
    19  	"reflect"
    20  	"strings"
    21  	"sync"
    22  	"testing"
    23  	"time"
    24  )
    25  
    26  var savedSupportedSignatureAlgorithmsTLS12 = supportedSignatureAlgorithmsTLS12
    27  
    28  func init() {
    29  	// TLS 1.3 is opt-in for Go 1.12, and RSA-PSS is disabled in TLS 1.2, but we
    30  	// want to run most tests with both enabled. TestTLS13Switch below and the
    31  	// "PSS-Disabled" recordings test the disabled behavior. See Issue 30055.
    32  	tls13Support.Do(func() {}) // defuse the sync.Once
    33  	tls13Support.cached = true
    34  	supportedSignatureAlgorithmsTLS12 = supportedSignatureAlgorithms
    35  }
    36  
    37  var rsaCertPEM = `-----BEGIN CERTIFICATE-----
    38  MIIB0zCCAX2gAwIBAgIJAI/M7BYjwB+uMA0GCSqGSIb3DQEBBQUAMEUxCzAJBgNV
    39  BAYTAkFVMRMwEQYDVQQIDApTb21lLVN0YXRlMSEwHwYDVQQKDBhJbnRlcm5ldCBX
    40  aWRnaXRzIFB0eSBMdGQwHhcNMTIwOTEyMjE1MjAyWhcNMTUwOTEyMjE1MjAyWjBF
    41  MQswCQYDVQQGEwJBVTETMBEGA1UECAwKU29tZS1TdGF0ZTEhMB8GA1UECgwYSW50
    42  ZXJuZXQgV2lkZ2l0cyBQdHkgTHRkMFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBANLJ
    43  hPHhITqQbPklG3ibCVxwGMRfp/v4XqhfdQHdcVfHap6NQ5Wok/4xIA+ui35/MmNa
    44  rtNuC+BdZ1tMuVCPFZcCAwEAAaNQME4wHQYDVR0OBBYEFJvKs8RfJaXTH08W+SGv
    45  zQyKn0H8MB8GA1UdIwQYMBaAFJvKs8RfJaXTH08W+SGvzQyKn0H8MAwGA1UdEwQF
    46  MAMBAf8wDQYJKoZIhvcNAQEFBQADQQBJlffJHybjDGxRMqaRmDhX0+6v02TUKZsW
    47  r5QuVbpQhH6u+0UgcW0jp9QwpxoPTLTWGXEWBBBurxFwiCBhkQ+V
    48  -----END CERTIFICATE-----
    49  `
    50  
    51  var rsaKeyPEM = `-----BEGIN RSA PRIVATE KEY-----
    52  MIIBOwIBAAJBANLJhPHhITqQbPklG3ibCVxwGMRfp/v4XqhfdQHdcVfHap6NQ5Wo
    53  k/4xIA+ui35/MmNartNuC+BdZ1tMuVCPFZcCAwEAAQJAEJ2N+zsR0Xn8/Q6twa4G
    54  6OB1M1WO+k+ztnX/1SvNeWu8D6GImtupLTYgjZcHufykj09jiHmjHx8u8ZZB/o1N
    55  MQIhAPW+eyZo7ay3lMz1V01WVjNKK9QSn1MJlb06h/LuYv9FAiEA25WPedKgVyCW
    56  SmUwbPw8fnTcpqDWE3yTO3vKcebqMSsCIBF3UmVue8YU3jybC3NxuXq3wNm34R8T
    57  xVLHwDXh/6NJAiEAl2oHGGLz64BuAfjKrqwz7qMYr9HCLIe/YsoWq/olzScCIQDi
    58  D2lWusoe2/nEqfDVVWGWlyJ7yOmqaVm/iNUN9B2N2g==
    59  -----END RSA PRIVATE KEY-----
    60  `
    61  
    62  // keyPEM is the same as rsaKeyPEM, but declares itself as just
    63  // "PRIVATE KEY", not "RSA PRIVATE KEY".  https://golang.org/issue/4477
    64  var keyPEM = `-----BEGIN PRIVATE KEY-----
    65  MIIBOwIBAAJBANLJhPHhITqQbPklG3ibCVxwGMRfp/v4XqhfdQHdcVfHap6NQ5Wo
    66  k/4xIA+ui35/MmNartNuC+BdZ1tMuVCPFZcCAwEAAQJAEJ2N+zsR0Xn8/Q6twa4G
    67  6OB1M1WO+k+ztnX/1SvNeWu8D6GImtupLTYgjZcHufykj09jiHmjHx8u8ZZB/o1N
    68  MQIhAPW+eyZo7ay3lMz1V01WVjNKK9QSn1MJlb06h/LuYv9FAiEA25WPedKgVyCW
    69  SmUwbPw8fnTcpqDWE3yTO3vKcebqMSsCIBF3UmVue8YU3jybC3NxuXq3wNm34R8T
    70  xVLHwDXh/6NJAiEAl2oHGGLz64BuAfjKrqwz7qMYr9HCLIe/YsoWq/olzScCIQDi
    71  D2lWusoe2/nEqfDVVWGWlyJ7yOmqaVm/iNUN9B2N2g==
    72  -----END PRIVATE KEY-----
    73  `
    74  
    75  var ecdsaCertPEM = `-----BEGIN CERTIFICATE-----
    76  MIIB/jCCAWICCQDscdUxw16XFDAJBgcqhkjOPQQBMEUxCzAJBgNVBAYTAkFVMRMw
    77  EQYDVQQIEwpTb21lLVN0YXRlMSEwHwYDVQQKExhJbnRlcm5ldCBXaWRnaXRzIFB0
    78  eSBMdGQwHhcNMTIxMTE0MTI0MDQ4WhcNMTUxMTE0MTI0MDQ4WjBFMQswCQYDVQQG
    79  EwJBVTETMBEGA1UECBMKU29tZS1TdGF0ZTEhMB8GA1UEChMYSW50ZXJuZXQgV2lk
    80  Z2l0cyBQdHkgTHRkMIGbMBAGByqGSM49AgEGBSuBBAAjA4GGAAQBY9+my9OoeSUR
    81  lDQdV/x8LsOuLilthhiS1Tz4aGDHIPwC1mlvnf7fg5lecYpMCrLLhauAc1UJXcgl
    82  01xoLuzgtAEAgv2P/jgytzRSpUYvgLBt1UA0leLYBy6mQQbrNEuqT3INapKIcUv8
    83  XxYP0xMEUksLPq6Ca+CRSqTtrd/23uTnapkwCQYHKoZIzj0EAQOBigAwgYYCQXJo
    84  A7Sl2nLVf+4Iu/tAX/IF4MavARKC4PPHK3zfuGfPR3oCCcsAoz3kAzOeijvd0iXb
    85  H5jBImIxPL4WxQNiBTexAkF8D1EtpYuWdlVQ80/h/f4pBcGiXPqX5h2PQSQY7hP1
    86  +jwM1FGS4fREIOvlBYr/SzzQRtwrvrzGYxDEDbsC0ZGRnA==
    87  -----END CERTIFICATE-----
    88  `
    89  
    90  var ecdsaKeyPEM = `-----BEGIN EC PARAMETERS-----
    91  BgUrgQQAIw==
    92  -----END EC PARAMETERS-----
    93  -----BEGIN EC PRIVATE KEY-----
    94  MIHcAgEBBEIBrsoKp0oqcv6/JovJJDoDVSGWdirrkgCWxrprGlzB9o0X8fV675X0
    95  NwuBenXFfeZvVcwluO7/Q9wkYoPd/t3jGImgBwYFK4EEACOhgYkDgYYABAFj36bL
    96  06h5JRGUNB1X/Hwuw64uKW2GGJLVPPhoYMcg/ALWaW+d/t+DmV5xikwKssuFq4Bz
    97  VQldyCXTXGgu7OC0AQCC/Y/+ODK3NFKlRi+AsG3VQDSV4tgHLqZBBus0S6pPcg1q
    98  kohxS/xfFg/TEwRSSws+roJr4JFKpO2t3/be5OdqmQ==
    99  -----END EC PRIVATE KEY-----
   100  `
   101  
   102  var keyPairTests = []struct {
   103  	algo string
   104  	cert string
   105  	key  string
   106  }{
   107  	{"ECDSA", ecdsaCertPEM, ecdsaKeyPEM},
   108  	{"RSA", rsaCertPEM, rsaKeyPEM},
   109  	{"RSA-untyped", rsaCertPEM, keyPEM}, // golang.org/issue/4477
   110  }
   111  
   112  func TestX509KeyPair(t *testing.T) {
   113  	t.Parallel()
   114  	var pem []byte
   115  	for _, test := range keyPairTests {
   116  		pem = []byte(test.cert + test.key)
   117  		if _, err := X509KeyPair(pem, pem); err != nil {
   118  			t.Errorf("Failed to load %s cert followed by %s key: %s", test.algo, test.algo, err)
   119  		}
   120  		pem = []byte(test.key + test.cert)
   121  		if _, err := X509KeyPair(pem, pem); err != nil {
   122  			t.Errorf("Failed to load %s key followed by %s cert: %s", test.algo, test.algo, err)
   123  		}
   124  	}
   125  }
   126  
   127  func TestX509KeyPairErrors(t *testing.T) {
   128  	_, err := X509KeyPair([]byte(rsaKeyPEM), []byte(rsaCertPEM))
   129  	if err == nil {
   130  		t.Fatalf("X509KeyPair didn't return an error when arguments were switched")
   131  	}
   132  	if subStr := "been switched"; !strings.Contains(err.Error(), subStr) {
   133  		t.Fatalf("Expected %q in the error when switching arguments to X509KeyPair, but the error was %q", subStr, err)
   134  	}
   135  
   136  	_, err = X509KeyPair([]byte(rsaCertPEM), []byte(rsaCertPEM))
   137  	if err == nil {
   138  		t.Fatalf("X509KeyPair didn't return an error when both arguments were certificates")
   139  	}
   140  	if subStr := "certificate"; !strings.Contains(err.Error(), subStr) {
   141  		t.Fatalf("Expected %q in the error when both arguments to X509KeyPair were certificates, but the error was %q", subStr, err)
   142  	}
   143  
   144  	const nonsensePEM = `
   145  -----BEGIN NONSENSE-----
   146  Zm9vZm9vZm9v
   147  -----END NONSENSE-----
   148  `
   149  
   150  	_, err = X509KeyPair([]byte(nonsensePEM), []byte(nonsensePEM))
   151  	if err == nil {
   152  		t.Fatalf("X509KeyPair didn't return an error when both arguments were nonsense")
   153  	}
   154  	if subStr := "NONSENSE"; !strings.Contains(err.Error(), subStr) {
   155  		t.Fatalf("Expected %q in the error when both arguments to X509KeyPair were nonsense, but the error was %q", subStr, err)
   156  	}
   157  }
   158  
   159  func TestX509MixedKeyPair(t *testing.T) {
   160  	if _, err := X509KeyPair([]byte(rsaCertPEM), []byte(ecdsaKeyPEM)); err == nil {
   161  		t.Error("Load of RSA certificate succeeded with ECDSA private key")
   162  	}
   163  	if _, err := X509KeyPair([]byte(ecdsaCertPEM), []byte(rsaKeyPEM)); err == nil {
   164  		t.Error("Load of ECDSA certificate succeeded with RSA private key")
   165  	}
   166  }
   167  
   168  func newLocalListener(t testing.TB) net.Listener {
   169  	ln, err := net.Listen("tcp", "127.0.0.1:0")
   170  	if err != nil {
   171  		ln, err = net.Listen("tcp6", "[::1]:0")
   172  	}
   173  	if err != nil {
   174  		t.Fatal(err)
   175  	}
   176  	return ln
   177  }
   178  
   179  func TestDialTimeout(t *testing.T) {
   180  	if testing.Short() {
   181  		t.Skip("skipping in short mode")
   182  	}
   183  	listener := newLocalListener(t)
   184  
   185  	addr := listener.Addr().String()
   186  	defer listener.Close()
   187  
   188  	complete := make(chan bool)
   189  	defer close(complete)
   190  
   191  	go func() {
   192  		conn, err := listener.Accept()
   193  		if err != nil {
   194  			t.Error(err)
   195  			return
   196  		}
   197  		<-complete
   198  		conn.Close()
   199  	}()
   200  
   201  	dialer := &net.Dialer{
   202  		Timeout: 10 * time.Millisecond,
   203  	}
   204  
   205  	var err error
   206  	if _, err = DialWithDialer(dialer, "tcp", addr, nil); err == nil {
   207  		t.Fatal("DialWithTimeout completed successfully")
   208  	}
   209  
   210  	if !isTimeoutError(err) {
   211  		t.Errorf("resulting error not a timeout: %v\nType %T: %#v", err, err, err)
   212  	}
   213  }
   214  
   215  func isTimeoutError(err error) bool {
   216  	if ne, ok := err.(net.Error); ok {
   217  		return ne.Timeout()
   218  	}
   219  	return false
   220  }
   221  
   222  // tests that Conn.Read returns (non-zero, io.EOF) instead of
   223  // (non-zero, nil) when a Close (alertCloseNotify) is sitting right
   224  // behind the application data in the buffer.
   225  func TestConnReadNonzeroAndEOF(t *testing.T) {
   226  	// This test is racy: it assumes that after a write to a
   227  	// localhost TCP connection, the peer TCP connection can
   228  	// immediately read it. Because it's racy, we skip this test
   229  	// in short mode, and then retry it several times with an
   230  	// increasing sleep in between our final write (via srv.Close
   231  	// below) and the following read.
   232  	if testing.Short() {
   233  		t.Skip("skipping in short mode")
   234  	}
   235  	var err error
   236  	for delay := time.Millisecond; delay <= 64*time.Millisecond; delay *= 2 {
   237  		if err = testConnReadNonzeroAndEOF(t, delay); err == nil {
   238  			return
   239  		}
   240  	}
   241  	t.Error(err)
   242  }
   243  
   244  func testConnReadNonzeroAndEOF(t *testing.T, delay time.Duration) error {
   245  	ln := newLocalListener(t)
   246  	defer ln.Close()
   247  
   248  	srvCh := make(chan *Conn, 1)
   249  	var serr error
   250  	go func() {
   251  		sconn, err := ln.Accept()
   252  		if err != nil {
   253  			serr = err
   254  			srvCh <- nil
   255  			return
   256  		}
   257  		serverConfig := testConfig.Clone()
   258  		srv := Server(sconn, serverConfig)
   259  		if err := srv.Handshake(); err != nil {
   260  			serr = fmt.Errorf("handshake: %v", err)
   261  			srvCh <- nil
   262  			return
   263  		}
   264  		srvCh <- srv
   265  	}()
   266  
   267  	clientConfig := testConfig.Clone()
   268  	// In TLS 1.3, alerts are encrypted and disguised as application data, so
   269  	// the opportunistic peek won't work.
   270  	clientConfig.MaxVersion = VersionTLS12
   271  	conn, err := Dial("tcp", ln.Addr().String(), clientConfig)
   272  	if err != nil {
   273  		t.Fatal(err)
   274  	}
   275  	defer conn.Close()
   276  
   277  	srv := <-srvCh
   278  	if srv == nil {
   279  		return serr
   280  	}
   281  
   282  	buf := make([]byte, 6)
   283  
   284  	srv.Write([]byte("foobar"))
   285  	n, err := conn.Read(buf)
   286  	if n != 6 || err != nil || string(buf) != "foobar" {
   287  		return fmt.Errorf("Read = %d, %v, data %q; want 6, nil, foobar", n, err, buf)
   288  	}
   289  
   290  	srv.Write([]byte("abcdef"))
   291  	srv.Close()
   292  	time.Sleep(delay)
   293  	n, err = conn.Read(buf)
   294  	if n != 6 || string(buf) != "abcdef" {
   295  		return fmt.Errorf("Read = %d, buf= %q; want 6, abcdef", n, buf)
   296  	}
   297  	if err != io.EOF {
   298  		return fmt.Errorf("Second Read error = %v; want io.EOF", err)
   299  	}
   300  	return nil
   301  }
   302  
   303  func TestTLSUniqueMatches(t *testing.T) {
   304  	ln := newLocalListener(t)
   305  	defer ln.Close()
   306  
   307  	serverTLSUniques := make(chan []byte)
   308  	go func() {
   309  		for i := 0; i < 2; i++ {
   310  			sconn, err := ln.Accept()
   311  			if err != nil {
   312  				t.Error(err)
   313  				return
   314  			}
   315  			serverConfig := testConfig.Clone()
   316  			serverConfig.MaxVersion = VersionTLS12 // TLSUnique is not defined in TLS 1.3
   317  			srv := Server(sconn, serverConfig)
   318  			if err := srv.Handshake(); err != nil {
   319  				t.Error(err)
   320  				return
   321  			}
   322  			serverTLSUniques <- srv.ConnectionState().TLSUnique
   323  		}
   324  	}()
   325  
   326  	clientConfig := testConfig.Clone()
   327  	clientConfig.ClientSessionCache = NewLRUClientSessionCache(1)
   328  	conn, err := Dial("tcp", ln.Addr().String(), clientConfig)
   329  	if err != nil {
   330  		t.Fatal(err)
   331  	}
   332  	if !bytes.Equal(conn.ConnectionState().TLSUnique, <-serverTLSUniques) {
   333  		t.Error("client and server channel bindings differ")
   334  	}
   335  	conn.Close()
   336  
   337  	conn, err = Dial("tcp", ln.Addr().String(), clientConfig)
   338  	if err != nil {
   339  		t.Fatal(err)
   340  	}
   341  	defer conn.Close()
   342  	if !conn.ConnectionState().DidResume {
   343  		t.Error("second session did not use resumption")
   344  	}
   345  	if !bytes.Equal(conn.ConnectionState().TLSUnique, <-serverTLSUniques) {
   346  		t.Error("client and server channel bindings differ when session resumption is used")
   347  	}
   348  }
   349  
   350  func TestVerifyHostname(t *testing.T) {
   351  	testenv.MustHaveExternalNetwork(t)
   352  
   353  	c, err := Dial("tcp", "www.google.com:https", nil)
   354  	if err != nil {
   355  		t.Fatal(err)
   356  	}
   357  	if err := c.VerifyHostname("www.google.com"); err != nil {
   358  		t.Fatalf("verify www.google.com: %v", err)
   359  	}
   360  	if err := c.VerifyHostname("www.yahoo.com"); err == nil {
   361  		t.Fatalf("verify www.yahoo.com succeeded")
   362  	}
   363  
   364  	c, err = Dial("tcp", "www.google.com:https", &Config{InsecureSkipVerify: true})
   365  	if err != nil {
   366  		t.Fatal(err)
   367  	}
   368  	if err := c.VerifyHostname("www.google.com"); err == nil {
   369  		t.Fatalf("verify www.google.com succeeded with InsecureSkipVerify=true")
   370  	}
   371  }
   372  
   373  func TestVerifyHostnameResumed(t *testing.T) {
   374  	t.Run("TLSv12", func(t *testing.T) { testVerifyHostnameResumed(t, VersionTLS12) })
   375  	t.Run("TLSv13", func(t *testing.T) { testVerifyHostnameResumed(t, VersionTLS13) })
   376  }
   377  
   378  func testVerifyHostnameResumed(t *testing.T, version uint16) {
   379  	testenv.MustHaveExternalNetwork(t)
   380  
   381  	config := &Config{
   382  		MaxVersion:         version,
   383  		ClientSessionCache: NewLRUClientSessionCache(32),
   384  	}
   385  	for i := 0; i < 2; i++ {
   386  		c, err := Dial("tcp", "mail.google.com:https", config)
   387  		if err != nil {
   388  			t.Fatalf("Dial #%d: %v", i, err)
   389  		}
   390  		cs := c.ConnectionState()
   391  		if i > 0 && !cs.DidResume {
   392  			t.Fatalf("Subsequent connection unexpectedly didn't resume")
   393  		}
   394  		if cs.Version != version {
   395  			t.Fatalf("Unexpectedly negotiated version %x", cs.Version)
   396  		}
   397  		if cs.VerifiedChains == nil {
   398  			t.Fatalf("Dial #%d: cs.VerifiedChains == nil", i)
   399  		}
   400  		if err := c.VerifyHostname("mail.google.com"); err != nil {
   401  			t.Fatalf("verify mail.google.com #%d: %v", i, err)
   402  		}
   403  		// Give the client a chance to read the server session tickets.
   404  		c.SetReadDeadline(time.Now().Add(500 * time.Millisecond))
   405  		if _, err := c.Read(make([]byte, 1)); err != nil {
   406  			if err, ok := err.(net.Error); !ok || !err.Timeout() {
   407  				t.Fatal(err)
   408  			}
   409  		}
   410  		c.Close()
   411  	}
   412  }
   413  
   414  func TestConnCloseBreakingWrite(t *testing.T) {
   415  	ln := newLocalListener(t)
   416  	defer ln.Close()
   417  
   418  	srvCh := make(chan *Conn, 1)
   419  	var serr error
   420  	var sconn net.Conn
   421  	go func() {
   422  		var err error
   423  		sconn, err = ln.Accept()
   424  		if err != nil {
   425  			serr = err
   426  			srvCh <- nil
   427  			return
   428  		}
   429  		serverConfig := testConfig.Clone()
   430  		srv := Server(sconn, serverConfig)
   431  		if err := srv.Handshake(); err != nil {
   432  			serr = fmt.Errorf("handshake: %v", err)
   433  			srvCh <- nil
   434  			return
   435  		}
   436  		srvCh <- srv
   437  	}()
   438  
   439  	cconn, err := net.Dial("tcp", ln.Addr().String())
   440  	if err != nil {
   441  		t.Fatal(err)
   442  	}
   443  	defer cconn.Close()
   444  
   445  	conn := &changeImplConn{
   446  		Conn: cconn,
   447  	}
   448  
   449  	clientConfig := testConfig.Clone()
   450  	tconn := Client(conn, clientConfig)
   451  	if err := tconn.Handshake(); err != nil {
   452  		t.Fatal(err)
   453  	}
   454  
   455  	srv := <-srvCh
   456  	if srv == nil {
   457  		t.Fatal(serr)
   458  	}
   459  	defer sconn.Close()
   460  
   461  	connClosed := make(chan struct{})
   462  	conn.closeFunc = func() error {
   463  		close(connClosed)
   464  		return nil
   465  	}
   466  
   467  	inWrite := make(chan bool, 1)
   468  	var errConnClosed = errors.New("conn closed for test")
   469  	conn.writeFunc = func(p []byte) (n int, err error) {
   470  		inWrite <- true
   471  		<-connClosed
   472  		return 0, errConnClosed
   473  	}
   474  
   475  	closeReturned := make(chan bool, 1)
   476  	go func() {
   477  		<-inWrite
   478  		tconn.Close() // test that this doesn't block forever.
   479  		closeReturned <- true
   480  	}()
   481  
   482  	_, err = tconn.Write([]byte("foo"))
   483  	if err != errConnClosed {
   484  		t.Errorf("Write error = %v; want errConnClosed", err)
   485  	}
   486  
   487  	<-closeReturned
   488  	if err := tconn.Close(); err != errClosed {
   489  		t.Errorf("Close error = %v; want errClosed", err)
   490  	}
   491  }
   492  
   493  func TestConnCloseWrite(t *testing.T) {
   494  	ln := newLocalListener(t)
   495  	defer ln.Close()
   496  
   497  	clientDoneChan := make(chan struct{})
   498  
   499  	serverCloseWrite := func() error {
   500  		sconn, err := ln.Accept()
   501  		if err != nil {
   502  			return fmt.Errorf("accept: %v", err)
   503  		}
   504  		defer sconn.Close()
   505  
   506  		serverConfig := testConfig.Clone()
   507  		srv := Server(sconn, serverConfig)
   508  		if err := srv.Handshake(); err != nil {
   509  			return fmt.Errorf("handshake: %v", err)
   510  		}
   511  		defer srv.Close()
   512  
   513  		data, err := ioutil.ReadAll(srv)
   514  		if err != nil {
   515  			return err
   516  		}
   517  		if len(data) > 0 {
   518  			return fmt.Errorf("Read data = %q; want nothing", data)
   519  		}
   520  
   521  		if err := srv.CloseWrite(); err != nil {
   522  			return fmt.Errorf("server CloseWrite: %v", err)
   523  		}
   524  
   525  		// Wait for clientCloseWrite to finish, so we know we
   526  		// tested the CloseWrite before we defer the
   527  		// sconn.Close above, which would also cause the
   528  		// client to unblock like CloseWrite.
   529  		<-clientDoneChan
   530  		return nil
   531  	}
   532  
   533  	clientCloseWrite := func() error {
   534  		defer close(clientDoneChan)
   535  
   536  		clientConfig := testConfig.Clone()
   537  		conn, err := Dial("tcp", ln.Addr().String(), clientConfig)
   538  		if err != nil {
   539  			return err
   540  		}
   541  		if err := conn.Handshake(); err != nil {
   542  			return err
   543  		}
   544  		defer conn.Close()
   545  
   546  		if err := conn.CloseWrite(); err != nil {
   547  			return fmt.Errorf("client CloseWrite: %v", err)
   548  		}
   549  
   550  		if _, err := conn.Write([]byte{0}); err != errShutdown {
   551  			return fmt.Errorf("CloseWrite error = %v; want errShutdown", err)
   552  		}
   553  
   554  		data, err := ioutil.ReadAll(conn)
   555  		if err != nil {
   556  			return err
   557  		}
   558  		if len(data) > 0 {
   559  			return fmt.Errorf("Read data = %q; want nothing", data)
   560  		}
   561  		return nil
   562  	}
   563  
   564  	errChan := make(chan error, 2)
   565  
   566  	go func() { errChan <- serverCloseWrite() }()
   567  	go func() { errChan <- clientCloseWrite() }()
   568  
   569  	for i := 0; i < 2; i++ {
   570  		select {
   571  		case err := <-errChan:
   572  			if err != nil {
   573  				t.Fatal(err)
   574  			}
   575  		case <-time.After(10 * time.Second):
   576  			t.Fatal("deadlock")
   577  		}
   578  	}
   579  
   580  	// Also test CloseWrite being called before the handshake is
   581  	// finished:
   582  	{
   583  		ln2 := newLocalListener(t)
   584  		defer ln2.Close()
   585  
   586  		netConn, err := net.Dial("tcp", ln2.Addr().String())
   587  		if err != nil {
   588  			t.Fatal(err)
   589  		}
   590  		defer netConn.Close()
   591  		conn := Client(netConn, testConfig.Clone())
   592  
   593  		if err := conn.CloseWrite(); err != errEarlyCloseWrite {
   594  			t.Errorf("CloseWrite error = %v; want errEarlyCloseWrite", err)
   595  		}
   596  	}
   597  }
   598  
   599  func TestWarningAlertFlood(t *testing.T) {
   600  	ln := newLocalListener(t)
   601  	defer ln.Close()
   602  
   603  	server := func() error {
   604  		sconn, err := ln.Accept()
   605  		if err != nil {
   606  			return fmt.Errorf("accept: %v", err)
   607  		}
   608  		defer sconn.Close()
   609  
   610  		serverConfig := testConfig.Clone()
   611  		srv := Server(sconn, serverConfig)
   612  		if err := srv.Handshake(); err != nil {
   613  			return fmt.Errorf("handshake: %v", err)
   614  		}
   615  		defer srv.Close()
   616  
   617  		_, err = ioutil.ReadAll(srv)
   618  		if err == nil {
   619  			return errors.New("unexpected lack of error from server")
   620  		}
   621  		const expected = "too many ignored"
   622  		if str := err.Error(); !strings.Contains(str, expected) {
   623  			return fmt.Errorf("expected error containing %q, but saw: %s", expected, str)
   624  		}
   625  
   626  		return nil
   627  	}
   628  
   629  	errChan := make(chan error, 1)
   630  	go func() { errChan <- server() }()
   631  
   632  	clientConfig := testConfig.Clone()
   633  	clientConfig.MaxVersion = VersionTLS12 // there are no warning alerts in TLS 1.3
   634  	conn, err := Dial("tcp", ln.Addr().String(), clientConfig)
   635  	if err != nil {
   636  		t.Fatal(err)
   637  	}
   638  	defer conn.Close()
   639  	if err := conn.Handshake(); err != nil {
   640  		t.Fatal(err)
   641  	}
   642  
   643  	for i := 0; i < maxUselessRecords+1; i++ {
   644  		conn.sendAlert(alertNoRenegotiation)
   645  	}
   646  
   647  	if err := <-errChan; err != nil {
   648  		t.Fatal(err)
   649  	}
   650  }
   651  
   652  func TestCloneFuncFields(t *testing.T) {
   653  	const expectedCount = 5
   654  	called := 0
   655  
   656  	c1 := Config{
   657  		Time: func() time.Time {
   658  			called |= 1 << 0
   659  			return time.Time{}
   660  		},
   661  		GetCertificate: func(*ClientHelloInfo) (*Certificate, error) {
   662  			called |= 1 << 1
   663  			return nil, nil
   664  		},
   665  		GetClientCertificate: func(*CertificateRequestInfo) (*Certificate, error) {
   666  			called |= 1 << 2
   667  			return nil, nil
   668  		},
   669  		GetConfigForClient: func(*ClientHelloInfo) (*Config, error) {
   670  			called |= 1 << 3
   671  			return nil, nil
   672  		},
   673  		VerifyPeerCertificate: func(rawCerts [][]byte, verifiedChains [][]*x509.Certificate) error {
   674  			called |= 1 << 4
   675  			return nil
   676  		},
   677  	}
   678  
   679  	c2 := c1.Clone()
   680  
   681  	c2.Time()
   682  	c2.GetCertificate(nil)
   683  	c2.GetClientCertificate(nil)
   684  	c2.GetConfigForClient(nil)
   685  	c2.VerifyPeerCertificate(nil, nil)
   686  
   687  	if called != (1<<expectedCount)-1 {
   688  		t.Fatalf("expected %d calls but saw calls %b", expectedCount, called)
   689  	}
   690  }
   691  
   692  func TestCloneNonFuncFields(t *testing.T) {
   693  	var c1 Config
   694  	v := reflect.ValueOf(&c1).Elem()
   695  
   696  	typ := v.Type()
   697  	for i := 0; i < typ.NumField(); i++ {
   698  		f := v.Field(i)
   699  		if !f.CanSet() {
   700  			// unexported field; not cloned.
   701  			continue
   702  		}
   703  
   704  		// testing/quick can't handle functions or interfaces and so
   705  		// isn't used here.
   706  		switch fn := typ.Field(i).Name; fn {
   707  		case "Rand":
   708  			f.Set(reflect.ValueOf(io.Reader(os.Stdin)))
   709  		case "Time", "GetCertificate", "GetConfigForClient", "VerifyPeerCertificate", "GetClientCertificate":
   710  			// DeepEqual can't compare functions. If you add a
   711  			// function field to this list, you must also change
   712  			// TestCloneFuncFields to ensure that the func field is
   713  			// cloned.
   714  		case "Certificates":
   715  			f.Set(reflect.ValueOf([]Certificate{
   716  				{Certificate: [][]byte{{'b'}}},
   717  			}))
   718  		case "NameToCertificate":
   719  			f.Set(reflect.ValueOf(map[string]*Certificate{"a": nil}))
   720  		case "RootCAs", "ClientCAs":
   721  			f.Set(reflect.ValueOf(x509.NewCertPool()))
   722  		case "ClientSessionCache":
   723  			f.Set(reflect.ValueOf(NewLRUClientSessionCache(10)))
   724  		case "KeyLogWriter":
   725  			f.Set(reflect.ValueOf(io.Writer(os.Stdout)))
   726  		case "NextProtos":
   727  			f.Set(reflect.ValueOf([]string{"a", "b"}))
   728  		case "ServerName":
   729  			f.Set(reflect.ValueOf("b"))
   730  		case "ClientAuth":
   731  			f.Set(reflect.ValueOf(VerifyClientCertIfGiven))
   732  		case "InsecureSkipVerify", "SessionTicketsDisabled", "DynamicRecordSizingDisabled", "PreferServerCipherSuites":
   733  			f.Set(reflect.ValueOf(true))
   734  		case "MinVersion", "MaxVersion":
   735  			f.Set(reflect.ValueOf(uint16(VersionTLS12)))
   736  		case "SessionTicketKey":
   737  			f.Set(reflect.ValueOf([32]byte{}))
   738  		case "CipherSuites":
   739  			f.Set(reflect.ValueOf([]uint16{1, 2}))
   740  		case "CurvePreferences":
   741  			f.Set(reflect.ValueOf([]CurveID{CurveP256}))
   742  		case "Renegotiation":
   743  			f.Set(reflect.ValueOf(RenegotiateOnceAsClient))
   744  		default:
   745  			t.Errorf("all fields must be accounted for, but saw unknown field %q", fn)
   746  		}
   747  	}
   748  
   749  	c2 := c1.Clone()
   750  	// DeepEqual also compares unexported fields, thus c2 needs to have run
   751  	// serverInit in order to be DeepEqual to c1. Cloning it and discarding
   752  	// the result is sufficient.
   753  	c2.Clone()
   754  
   755  	if !reflect.DeepEqual(&c1, c2) {
   756  		t.Errorf("clone failed to copy a field")
   757  	}
   758  }
   759  
   760  // changeImplConn is a net.Conn which can change its Write and Close
   761  // methods.
   762  type changeImplConn struct {
   763  	net.Conn
   764  	writeFunc func([]byte) (int, error)
   765  	closeFunc func() error
   766  }
   767  
   768  func (w *changeImplConn) Write(p []byte) (n int, err error) {
   769  	if w.writeFunc != nil {
   770  		return w.writeFunc(p)
   771  	}
   772  	return w.Conn.Write(p)
   773  }
   774  
   775  func (w *changeImplConn) Close() error {
   776  	if w.closeFunc != nil {
   777  		return w.closeFunc()
   778  	}
   779  	return w.Conn.Close()
   780  }
   781  
   782  func throughput(b *testing.B, version uint16, totalBytes int64, dynamicRecordSizingDisabled bool) {
   783  	ln := newLocalListener(b)
   784  	defer ln.Close()
   785  
   786  	N := b.N
   787  
   788  	// Less than 64KB because Windows appears to use a TCP rwin < 64KB.
   789  	// See Issue #15899.
   790  	const bufsize = 32 << 10
   791  
   792  	go func() {
   793  		buf := make([]byte, bufsize)
   794  		for i := 0; i < N; i++ {
   795  			sconn, err := ln.Accept()
   796  			if err != nil {
   797  				// panic rather than synchronize to avoid benchmark overhead
   798  				// (cannot call b.Fatal in goroutine)
   799  				panic(fmt.Errorf("accept: %v", err))
   800  			}
   801  			serverConfig := testConfig.Clone()
   802  			serverConfig.CipherSuites = nil // the defaults may prefer faster ciphers
   803  			serverConfig.DynamicRecordSizingDisabled = dynamicRecordSizingDisabled
   804  			srv := Server(sconn, serverConfig)
   805  			if err := srv.Handshake(); err != nil {
   806  				panic(fmt.Errorf("handshake: %v", err))
   807  			}
   808  			if _, err := io.CopyBuffer(srv, srv, buf); err != nil {
   809  				panic(fmt.Errorf("copy buffer: %v", err))
   810  			}
   811  		}
   812  	}()
   813  
   814  	b.SetBytes(totalBytes)
   815  	clientConfig := testConfig.Clone()
   816  	clientConfig.CipherSuites = nil // the defaults may prefer faster ciphers
   817  	clientConfig.DynamicRecordSizingDisabled = dynamicRecordSizingDisabled
   818  	clientConfig.MaxVersion = version
   819  
   820  	buf := make([]byte, bufsize)
   821  	chunks := int(math.Ceil(float64(totalBytes) / float64(len(buf))))
   822  	for i := 0; i < N; i++ {
   823  		conn, err := Dial("tcp", ln.Addr().String(), clientConfig)
   824  		if err != nil {
   825  			b.Fatal(err)
   826  		}
   827  		for j := 0; j < chunks; j++ {
   828  			_, err := conn.Write(buf)
   829  			if err != nil {
   830  				b.Fatal(err)
   831  			}
   832  			_, err = io.ReadFull(conn, buf)
   833  			if err != nil {
   834  				b.Fatal(err)
   835  			}
   836  		}
   837  		conn.Close()
   838  	}
   839  }
   840  
   841  func BenchmarkThroughput(b *testing.B) {
   842  	for _, mode := range []string{"Max", "Dynamic"} {
   843  		for size := 1; size <= 64; size <<= 1 {
   844  			name := fmt.Sprintf("%sPacket/%dMB", mode, size)
   845  			b.Run(name, func(b *testing.B) {
   846  				b.Run("TLSv12", func(b *testing.B) {
   847  					throughput(b, VersionTLS12, int64(size<<20), mode == "Max")
   848  				})
   849  				b.Run("TLSv13", func(b *testing.B) {
   850  					throughput(b, VersionTLS13, int64(size<<20), mode == "Max")
   851  				})
   852  			})
   853  		}
   854  	}
   855  }
   856  
   857  type slowConn struct {
   858  	net.Conn
   859  	bps int
   860  }
   861  
   862  func (c *slowConn) Write(p []byte) (int, error) {
   863  	if c.bps == 0 {
   864  		panic("too slow")
   865  	}
   866  	t0 := time.Now()
   867  	wrote := 0
   868  	for wrote < len(p) {
   869  		time.Sleep(100 * time.Microsecond)
   870  		allowed := int(time.Since(t0).Seconds()*float64(c.bps)) / 8
   871  		if allowed > len(p) {
   872  			allowed = len(p)
   873  		}
   874  		if wrote < allowed {
   875  			n, err := c.Conn.Write(p[wrote:allowed])
   876  			wrote += n
   877  			if err != nil {
   878  				return wrote, err
   879  			}
   880  		}
   881  	}
   882  	return len(p), nil
   883  }
   884  
   885  func latency(b *testing.B, version uint16, bps int, dynamicRecordSizingDisabled bool) {
   886  	ln := newLocalListener(b)
   887  	defer ln.Close()
   888  
   889  	N := b.N
   890  
   891  	go func() {
   892  		for i := 0; i < N; i++ {
   893  			sconn, err := ln.Accept()
   894  			if err != nil {
   895  				// panic rather than synchronize to avoid benchmark overhead
   896  				// (cannot call b.Fatal in goroutine)
   897  				panic(fmt.Errorf("accept: %v", err))
   898  			}
   899  			serverConfig := testConfig.Clone()
   900  			serverConfig.DynamicRecordSizingDisabled = dynamicRecordSizingDisabled
   901  			srv := Server(&slowConn{sconn, bps}, serverConfig)
   902  			if err := srv.Handshake(); err != nil {
   903  				panic(fmt.Errorf("handshake: %v", err))
   904  			}
   905  			io.Copy(srv, srv)
   906  		}
   907  	}()
   908  
   909  	clientConfig := testConfig.Clone()
   910  	clientConfig.DynamicRecordSizingDisabled = dynamicRecordSizingDisabled
   911  	clientConfig.MaxVersion = version
   912  
   913  	buf := make([]byte, 16384)
   914  	peek := make([]byte, 1)
   915  
   916  	for i := 0; i < N; i++ {
   917  		conn, err := Dial("tcp", ln.Addr().String(), clientConfig)
   918  		if err != nil {
   919  			b.Fatal(err)
   920  		}
   921  		// make sure we're connected and previous connection has stopped
   922  		if _, err := conn.Write(buf[:1]); err != nil {
   923  			b.Fatal(err)
   924  		}
   925  		if _, err := io.ReadFull(conn, peek); err != nil {
   926  			b.Fatal(err)
   927  		}
   928  		if _, err := conn.Write(buf); err != nil {
   929  			b.Fatal(err)
   930  		}
   931  		if _, err = io.ReadFull(conn, peek); err != nil {
   932  			b.Fatal(err)
   933  		}
   934  		conn.Close()
   935  	}
   936  }
   937  
   938  func BenchmarkLatency(b *testing.B) {
   939  	for _, mode := range []string{"Max", "Dynamic"} {
   940  		for _, kbps := range []int{200, 500, 1000, 2000, 5000} {
   941  			name := fmt.Sprintf("%sPacket/%dkbps", mode, kbps)
   942  			b.Run(name, func(b *testing.B) {
   943  				b.Run("TLSv12", func(b *testing.B) {
   944  					latency(b, VersionTLS12, kbps*1000, mode == "Max")
   945  				})
   946  				b.Run("TLSv13", func(b *testing.B) {
   947  					latency(b, VersionTLS13, kbps*1000, mode == "Max")
   948  				})
   949  			})
   950  		}
   951  	}
   952  }
   953  
   954  func TestConnectionStateMarshal(t *testing.T) {
   955  	cs := &ConnectionState{}
   956  	_, err := json.Marshal(cs)
   957  	if err != nil {
   958  		t.Errorf("json.Marshal failed on ConnectionState: %v", err)
   959  	}
   960  }
   961  
   962  func TestConnectionState(t *testing.T) {
   963  	issuer, err := x509.ParseCertificate(testRSACertificateIssuer)
   964  	if err != nil {
   965  		panic(err)
   966  	}
   967  	rootCAs := x509.NewCertPool()
   968  	rootCAs.AddCert(issuer)
   969  
   970  	now := func() time.Time { return time.Unix(1476984729, 0) }
   971  
   972  	const alpnProtocol = "golang"
   973  	const serverName = "example.golang"
   974  	var scts = [][]byte{[]byte("dummy sct 1"), []byte("dummy sct 2")}
   975  	var ocsp = []byte("dummy ocsp")
   976  
   977  	for _, v := range []uint16{VersionTLS12, VersionTLS13} {
   978  		var name string
   979  		switch v {
   980  		case VersionTLS12:
   981  			name = "TLSv12"
   982  		case VersionTLS13:
   983  			name = "TLSv13"
   984  		}
   985  		t.Run(name, func(t *testing.T) {
   986  			config := &Config{
   987  				Time:         now,
   988  				Rand:         zeroSource{},
   989  				Certificates: make([]Certificate, 1),
   990  				MaxVersion:   v,
   991  				RootCAs:      rootCAs,
   992  				ClientCAs:    rootCAs,
   993  				ClientAuth:   RequireAndVerifyClientCert,
   994  				NextProtos:   []string{alpnProtocol},
   995  				ServerName:   serverName,
   996  			}
   997  			config.Certificates[0].Certificate = [][]byte{testRSACertificate}
   998  			config.Certificates[0].PrivateKey = testRSAPrivateKey
   999  			config.Certificates[0].SignedCertificateTimestamps = scts
  1000  			config.Certificates[0].OCSPStaple = ocsp
  1001  
  1002  			ss, cs, err := testHandshake(t, config, config)
  1003  			if err != nil {
  1004  				t.Fatalf("Handshake failed: %v", err)
  1005  			}
  1006  
  1007  			if ss.Version != v || cs.Version != v {
  1008  				t.Errorf("Got versions %x (server) and %x (client), expected %x", ss.Version, cs.Version, v)
  1009  			}
  1010  
  1011  			if !ss.HandshakeComplete || !cs.HandshakeComplete {
  1012  				t.Errorf("Got HandshakeComplete %v (server) and %v (client), expected true", ss.HandshakeComplete, cs.HandshakeComplete)
  1013  			}
  1014  
  1015  			if ss.DidResume || cs.DidResume {
  1016  				t.Errorf("Got DidResume %v (server) and %v (client), expected false", ss.DidResume, cs.DidResume)
  1017  			}
  1018  
  1019  			if ss.CipherSuite == 0 || cs.CipherSuite == 0 {
  1020  				t.Errorf("Got invalid cipher suite: %v (server) and %v (client)", ss.CipherSuite, cs.CipherSuite)
  1021  			}
  1022  
  1023  			if ss.NegotiatedProtocol != alpnProtocol || cs.NegotiatedProtocol != alpnProtocol {
  1024  				t.Errorf("Got negotiated protocol %q (server) and %q (client), expected %q", ss.NegotiatedProtocol, cs.NegotiatedProtocol, alpnProtocol)
  1025  			}
  1026  
  1027  			if !cs.NegotiatedProtocolIsMutual {
  1028  				t.Errorf("Got false NegotiatedProtocolIsMutual on the client side")
  1029  			}
  1030  			// NegotiatedProtocolIsMutual on the server side is unspecified.
  1031  
  1032  			if ss.ServerName != serverName {
  1033  				t.Errorf("Got server name %q, expected %q", ss.ServerName, serverName)
  1034  			}
  1035  			if cs.ServerName != "" {
  1036  				t.Errorf("Got unexpected server name on the client side")
  1037  			}
  1038  
  1039  			if len(ss.PeerCertificates) != 1 || len(cs.PeerCertificates) != 1 {
  1040  				t.Errorf("Got %d (server) and %d (client) peer certificates, expected %d", len(ss.PeerCertificates), len(cs.PeerCertificates), 1)
  1041  			}
  1042  
  1043  			if len(ss.VerifiedChains) != 1 || len(cs.VerifiedChains) != 1 {
  1044  				t.Errorf("Got %d (server) and %d (client) verified chains, expected %d", len(ss.VerifiedChains), len(cs.VerifiedChains), 1)
  1045  			} else if len(ss.VerifiedChains[0]) != 2 || len(cs.VerifiedChains[0]) != 2 {
  1046  				t.Errorf("Got %d (server) and %d (client) long verified chain, expected %d", len(ss.VerifiedChains[0]), len(cs.VerifiedChains[0]), 2)
  1047  			}
  1048  
  1049  			if len(cs.SignedCertificateTimestamps) != 2 {
  1050  				t.Errorf("Got %d SCTs, expected %d", len(cs.SignedCertificateTimestamps), 2)
  1051  			}
  1052  			if !bytes.Equal(cs.OCSPResponse, ocsp) {
  1053  				t.Errorf("Got OCSPs %x, expected %x", cs.OCSPResponse, ocsp)
  1054  			}
  1055  			// Only TLS 1.3 supports OCSP and SCTs on client certs.
  1056  			if v == VersionTLS13 {
  1057  				if len(ss.SignedCertificateTimestamps) != 2 {
  1058  					t.Errorf("Got %d client SCTs, expected %d", len(ss.SignedCertificateTimestamps), 2)
  1059  				}
  1060  				if !bytes.Equal(ss.OCSPResponse, ocsp) {
  1061  					t.Errorf("Got client OCSPs %x, expected %x", ss.OCSPResponse, ocsp)
  1062  				}
  1063  			}
  1064  
  1065  			if v == VersionTLS13 {
  1066  				if ss.TLSUnique != nil || cs.TLSUnique != nil {
  1067  					t.Errorf("Got TLSUnique %x (server) and %x (client), expected nil in TLS 1.3", ss.TLSUnique, cs.TLSUnique)
  1068  				}
  1069  			} else {
  1070  				if ss.TLSUnique == nil || cs.TLSUnique == nil {
  1071  					t.Errorf("Got TLSUnique %x (server) and %x (client), expected non-nil", ss.TLSUnique, cs.TLSUnique)
  1072  				}
  1073  			}
  1074  		})
  1075  	}
  1076  }
  1077  
  1078  // TestEscapeRoute tests that the library will still work if support for TLS 1.3
  1079  // is dropped later in the Go 1.12 cycle.
  1080  func TestEscapeRoute(t *testing.T) {
  1081  	defer func(savedSupportedVersions []uint16) {
  1082  		supportedVersions = savedSupportedVersions
  1083  	}(supportedVersions)
  1084  	supportedVersions = []uint16{
  1085  		VersionTLS12,
  1086  		VersionTLS11,
  1087  		VersionTLS10,
  1088  		VersionSSL30,
  1089  	}
  1090  
  1091  	expectVersion(t, testConfig, testConfig, VersionTLS12)
  1092  }
  1093  
  1094  func expectVersion(t *testing.T, clientConfig, serverConfig *Config, v uint16) {
  1095  	ss, cs, err := testHandshake(t, clientConfig, serverConfig)
  1096  	if err != nil {
  1097  		t.Fatalf("Handshake failed: %v", err)
  1098  	}
  1099  	if ss.Version != v {
  1100  		t.Errorf("Server negotiated version %x, expected %x", cs.Version, v)
  1101  	}
  1102  	if cs.Version != v {
  1103  		t.Errorf("Client negotiated version %x, expected %x", cs.Version, v)
  1104  	}
  1105  }
  1106  
  1107  // TestTLS13Switch checks the behavior of GODEBUG=tls13=[0|1]. See Issue 30055.
  1108  func TestTLS13Switch(t *testing.T) {
  1109  	defer func(savedGODEBUG string) {
  1110  		os.Setenv("GODEBUG", savedGODEBUG)
  1111  	}(os.Getenv("GODEBUG"))
  1112  
  1113  	os.Setenv("GODEBUG", "tls13=0")
  1114  	tls13Support.Once = sync.Once{} // reset the cache
  1115  
  1116  	tls12Config := testConfig.Clone()
  1117  	tls12Config.MaxVersion = VersionTLS12
  1118  	expectVersion(t, testConfig, testConfig, VersionTLS12)
  1119  	expectVersion(t, tls12Config, testConfig, VersionTLS12)
  1120  	expectVersion(t, testConfig, tls12Config, VersionTLS12)
  1121  	expectVersion(t, tls12Config, tls12Config, VersionTLS12)
  1122  
  1123  	os.Setenv("GODEBUG", "tls13=1")
  1124  	tls13Support.Once = sync.Once{} // reset the cache
  1125  
  1126  	expectVersion(t, testConfig, testConfig, VersionTLS13)
  1127  	expectVersion(t, tls12Config, testConfig, VersionTLS12)
  1128  	expectVersion(t, testConfig, tls12Config, VersionTLS12)
  1129  	expectVersion(t, tls12Config, tls12Config, VersionTLS12)
  1130  }
  1131  
  1132  // Issue 28744: Ensure that we don't modify memory
  1133  // that Config doesn't own such as Certificates.
  1134  func TestBuildNameToCertificate_doesntModifyCertificates(t *testing.T) {
  1135  	c0 := Certificate{
  1136  		Certificate: [][]byte{testRSACertificate},
  1137  		PrivateKey:  testRSAPrivateKey,
  1138  	}
  1139  	c1 := Certificate{
  1140  		Certificate: [][]byte{testSNICertificate},
  1141  		PrivateKey:  testRSAPrivateKey,
  1142  	}
  1143  	config := testConfig.Clone()
  1144  	config.Certificates = []Certificate{c0, c1}
  1145  
  1146  	config.BuildNameToCertificate()
  1147  	got := config.Certificates
  1148  	want := []Certificate{c0, c1}
  1149  	if !reflect.DeepEqual(got, want) {
  1150  		t.Fatalf("Certificates were mutated by BuildNameToCertificate\nGot: %#v\nWant: %#v\n", got, want)
  1151  	}
  1152  }