388 lines
12 KiB
Go
388 lines
12 KiB
Go
// Copyright 2009 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
// Package tls partially implements TLS 1.2, as specified in RFC 5246,
|
|
// and TLS 1.3, as specified in RFC 8446.
|
|
package tls
|
|
|
|
// BUG(agl): The crypto/tls package only implements some countermeasures
|
|
// against Lucky13 attacks on CBC-mode encryption, and only on SHA1
|
|
// variants. See http://www.isg.rhul.ac.uk/tls/TLStiming.pdf and
|
|
// https://www.imperialviolet.org/2013/02/04/luckythirteen.html.
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"crypto"
|
|
"crypto/ecdsa"
|
|
"crypto/ed25519"
|
|
"crypto/rsa"
|
|
"crypto/x509"
|
|
"encoding/pem"
|
|
"errors"
|
|
"fmt"
|
|
"net"
|
|
"os"
|
|
"strings"
|
|
"time"
|
|
)
|
|
|
|
// Server returns a new TLS server side connection
|
|
// using conn as the underlying transport.
|
|
// The configuration config must be non-nil and must include
|
|
// at least one certificate or else set GetCertificate.
|
|
func Server(conn net.Conn, config *Config) *Conn {
|
|
c := &Conn{
|
|
conn: conn,
|
|
config: config,
|
|
}
|
|
c.handshakeFn = c.serverHandshake
|
|
return c
|
|
}
|
|
|
|
// Client returns a new TLS client side connection
|
|
// using conn as the underlying transport.
|
|
// The config cannot be nil: users must set either ServerName or
|
|
// InsecureSkipVerify in the config.
|
|
func Client(conn net.Conn, config *Config) *Conn {
|
|
c := &Conn{
|
|
conn: conn,
|
|
config: config,
|
|
isClient: true,
|
|
}
|
|
c.handshakeFn = c.clientHandshake
|
|
return c
|
|
}
|
|
|
|
// A listener implements a network listener (net.Listener) for TLS connections.
|
|
type listener struct {
|
|
net.Listener
|
|
config *Config
|
|
}
|
|
|
|
// Accept waits for and returns the next incoming TLS connection.
|
|
// The returned connection is of type *Conn.
|
|
func (l *listener) Accept() (net.Conn, error) {
|
|
c, err := l.Listener.Accept()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return Server(c, l.config), nil
|
|
}
|
|
|
|
// NewListener creates a Listener which accepts connections from an inner
|
|
// Listener and wraps each connection with Server.
|
|
// The configuration config must be non-nil and must include
|
|
// at least one certificate or else set GetCertificate.
|
|
func NewListener(inner net.Listener, config *Config) net.Listener {
|
|
l := new(listener)
|
|
l.Listener = inner
|
|
l.config = config
|
|
return l
|
|
}
|
|
|
|
// Listen creates a TLS listener accepting connections on the
|
|
// given network address using net.Listen.
|
|
// The configuration config must be non-nil and must include
|
|
// at least one certificate or else set GetCertificate.
|
|
func Listen(network, laddr string, config *Config) (net.Listener, error) {
|
|
if config == nil || len(config.Certificates) == 0 &&
|
|
config.GetCertificate == nil && config.GetConfigForClient == nil {
|
|
return nil, errors.New("tls: neither Certificates, GetCertificate, nor GetConfigForClient set in Config")
|
|
}
|
|
l, err := net.Listen(network, laddr)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return NewListener(l, config), nil
|
|
}
|
|
|
|
type timeoutError struct{}
|
|
|
|
func (timeoutError) Error() string { return "tls: DialWithDialer timed out" }
|
|
func (timeoutError) Timeout() bool { return true }
|
|
func (timeoutError) Temporary() bool { return true }
|
|
|
|
// DialWithDialer connects to the given network address using dialer.Dial and
|
|
// then initiates a TLS handshake, returning the resulting TLS connection. Any
|
|
// timeout or deadline given in the dialer apply to connection and TLS
|
|
// handshake as a whole.
|
|
//
|
|
// DialWithDialer interprets a nil configuration as equivalent to the zero
|
|
// configuration; see the documentation of Config for the defaults.
|
|
func DialWithDialer(dialer *net.Dialer, network, addr string, config *Config) (*Conn, error) {
|
|
return dial(context.Background(), dialer, network, addr, config)
|
|
}
|
|
|
|
func dial(ctx context.Context, netDialer *net.Dialer, network, addr string, config *Config) (*Conn, error) {
|
|
// We want the Timeout and Deadline values from dialer to cover the
|
|
// whole process: TCP connection and TLS handshake. This means that we
|
|
// also need to start our own timers now.
|
|
timeout := netDialer.Timeout
|
|
|
|
if !netDialer.Deadline.IsZero() {
|
|
deadlineTimeout := time.Until(netDialer.Deadline)
|
|
if timeout == 0 || deadlineTimeout < timeout {
|
|
timeout = deadlineTimeout
|
|
}
|
|
}
|
|
|
|
// hsErrCh is non-nil if we might not wait for Handshake to complete.
|
|
var hsErrCh chan error
|
|
if timeout != 0 || ctx.Done() != nil {
|
|
hsErrCh = make(chan error, 2)
|
|
}
|
|
if timeout != 0 {
|
|
timer := time.AfterFunc(timeout, func() {
|
|
hsErrCh <- timeoutError{}
|
|
})
|
|
defer timer.Stop()
|
|
}
|
|
|
|
rawConn, err := netDialer.DialContext(ctx, network, addr)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
colonPos := strings.LastIndex(addr, ":")
|
|
if colonPos == -1 {
|
|
colonPos = len(addr)
|
|
}
|
|
hostname := addr[:colonPos]
|
|
|
|
if config == nil {
|
|
config = defaultConfig()
|
|
}
|
|
// If no ServerName is set, infer the ServerName
|
|
// from the hostname we're connecting to.
|
|
if config.ServerName == "" {
|
|
// Make a copy to avoid polluting argument or default.
|
|
c := config.Clone()
|
|
c.ServerName = hostname
|
|
config = c
|
|
}
|
|
|
|
conn := Client(rawConn, config)
|
|
|
|
if hsErrCh == nil {
|
|
err = conn.Handshake()
|
|
} else {
|
|
go func() {
|
|
hsErrCh <- conn.Handshake()
|
|
}()
|
|
|
|
select {
|
|
case <-ctx.Done():
|
|
err = ctx.Err()
|
|
case err = <-hsErrCh:
|
|
if err != nil {
|
|
// If the error was due to the context
|
|
// closing, prefer the context's error, rather
|
|
// than some random network teardown error.
|
|
if e := ctx.Err(); e != nil {
|
|
err = e
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if err != nil {
|
|
rawConn.Close()
|
|
return nil, err
|
|
}
|
|
|
|
return conn, nil
|
|
}
|
|
|
|
// Dial connects to the given network address using net.Dial
|
|
// and then initiates a TLS handshake, returning the resulting
|
|
// TLS connection.
|
|
// Dial interprets a nil configuration as equivalent to
|
|
// the zero configuration; see the documentation of Config
|
|
// for the defaults.
|
|
func Dial(network, addr string, config *Config) (*Conn, error) {
|
|
return DialWithDialer(new(net.Dialer), network, addr, config)
|
|
}
|
|
|
|
// Dialer dials TLS connections given a configuration and a Dialer for the
|
|
// underlying connection.
|
|
type Dialer struct {
|
|
// NetDialer is the optional dialer to use for the TLS connections'
|
|
// underlying TCP connections.
|
|
// A nil NetDialer is equivalent to the net.Dialer zero value.
|
|
NetDialer *net.Dialer
|
|
|
|
// Config is the TLS configuration to use for new connections.
|
|
// A nil configuration is equivalent to the zero
|
|
// configuration; see the documentation of Config for the
|
|
// defaults.
|
|
Config *Config
|
|
}
|
|
|
|
// Dial connects to the given network address and initiates a TLS
|
|
// handshake, returning the resulting TLS connection.
|
|
//
|
|
// The returned Conn, if any, will always be of type *Conn.
|
|
func (d *Dialer) Dial(network, addr string) (net.Conn, error) {
|
|
return d.DialContext(context.Background(), network, addr)
|
|
}
|
|
|
|
func (d *Dialer) netDialer() *net.Dialer {
|
|
if d.NetDialer != nil {
|
|
return d.NetDialer
|
|
}
|
|
return new(net.Dialer)
|
|
}
|
|
|
|
// DialContext connects to the given network address and initiates a TLS
|
|
// handshake, returning the resulting TLS connection.
|
|
//
|
|
// The provided Context must be non-nil. If the context expires before
|
|
// the connection is complete, an error is returned. Once successfully
|
|
// connected, any expiration of the context will not affect the
|
|
// connection.
|
|
//
|
|
// The returned Conn, if any, will always be of type *Conn.
|
|
func (d *Dialer) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
|
|
c, err := dial(ctx, d.netDialer(), network, addr, d.Config)
|
|
if err != nil {
|
|
// Don't return c (a typed nil) in an interface.
|
|
return nil, err
|
|
}
|
|
return c, nil
|
|
}
|
|
|
|
// LoadX509KeyPair reads and parses a public/private key pair from a pair
|
|
// of files. The files must contain PEM encoded data. The certificate file
|
|
// may contain intermediate certificates following the leaf certificate to
|
|
// form a certificate chain. On successful return, Certificate.Leaf will
|
|
// be nil because the parsed form of the certificate is not retained.
|
|
func LoadX509KeyPair(certFile, keyFile string) (Certificate, error) {
|
|
certPEMBlock, err := os.ReadFile(certFile)
|
|
if err != nil {
|
|
return Certificate{}, err
|
|
}
|
|
keyPEMBlock, err := os.ReadFile(keyFile)
|
|
if err != nil {
|
|
return Certificate{}, err
|
|
}
|
|
return X509KeyPair(certPEMBlock, keyPEMBlock)
|
|
}
|
|
|
|
// X509KeyPair parses a public/private key pair from a pair of
|
|
// PEM encoded data. On successful return, Certificate.Leaf will be nil because
|
|
// the parsed form of the certificate is not retained.
|
|
func X509KeyPair(certPEMBlock, keyPEMBlock []byte) (Certificate, error) {
|
|
fail := func(err error) (Certificate, error) { return Certificate{}, err }
|
|
|
|
var cert Certificate
|
|
var skippedBlockTypes []string
|
|
for {
|
|
var certDERBlock *pem.Block
|
|
certDERBlock, certPEMBlock = pem.Decode(certPEMBlock)
|
|
if certDERBlock == nil {
|
|
break
|
|
}
|
|
if certDERBlock.Type == "CERTIFICATE" {
|
|
cert.Certificate = append(cert.Certificate, certDERBlock.Bytes)
|
|
} else {
|
|
skippedBlockTypes = append(skippedBlockTypes, certDERBlock.Type)
|
|
}
|
|
}
|
|
|
|
if len(cert.Certificate) == 0 {
|
|
if len(skippedBlockTypes) == 0 {
|
|
return fail(errors.New("tls: failed to find any PEM data in certificate input"))
|
|
}
|
|
if len(skippedBlockTypes) == 1 && strings.HasSuffix(skippedBlockTypes[0], "PRIVATE KEY") {
|
|
return fail(errors.New("tls: failed to find certificate PEM data in certificate input, but did find a private key; PEM inputs may have been switched"))
|
|
}
|
|
return fail(fmt.Errorf("tls: failed to find \"CERTIFICATE\" PEM block in certificate input after skipping PEM blocks of the following types: %v", skippedBlockTypes))
|
|
}
|
|
|
|
skippedBlockTypes = skippedBlockTypes[:0]
|
|
var keyDERBlock *pem.Block
|
|
for {
|
|
keyDERBlock, keyPEMBlock = pem.Decode(keyPEMBlock)
|
|
if keyDERBlock == nil {
|
|
if len(skippedBlockTypes) == 0 {
|
|
return fail(errors.New("tls: failed to find any PEM data in key input"))
|
|
}
|
|
if len(skippedBlockTypes) == 1 && skippedBlockTypes[0] == "CERTIFICATE" {
|
|
return fail(errors.New("tls: found a certificate rather than a key in the PEM for the private key"))
|
|
}
|
|
return fail(fmt.Errorf("tls: failed to find PEM block with type ending in \"PRIVATE KEY\" in key input after skipping PEM blocks of the following types: %v", skippedBlockTypes))
|
|
}
|
|
if keyDERBlock.Type == "PRIVATE KEY" || strings.HasSuffix(keyDERBlock.Type, " PRIVATE KEY") {
|
|
break
|
|
}
|
|
skippedBlockTypes = append(skippedBlockTypes, keyDERBlock.Type)
|
|
}
|
|
|
|
// We don't need to parse the public key for TLS, but we so do anyway
|
|
// to check that it looks sane and matches the private key.
|
|
x509Cert, err := x509.ParseCertificate(cert.Certificate[0])
|
|
if err != nil {
|
|
return fail(err)
|
|
}
|
|
|
|
cert.PrivateKey, err = parsePrivateKey(keyDERBlock.Bytes)
|
|
if err != nil {
|
|
return fail(err)
|
|
}
|
|
|
|
switch pub := x509Cert.PublicKey.(type) {
|
|
case *rsa.PublicKey:
|
|
priv, ok := cert.PrivateKey.(*rsa.PrivateKey)
|
|
if !ok {
|
|
return fail(errors.New("tls: private key type does not match public key type"))
|
|
}
|
|
if pub.N.Cmp(priv.N) != 0 {
|
|
return fail(errors.New("tls: private key does not match public key"))
|
|
}
|
|
case *ecdsa.PublicKey:
|
|
priv, ok := cert.PrivateKey.(*ecdsa.PrivateKey)
|
|
if !ok {
|
|
return fail(errors.New("tls: private key type does not match public key type"))
|
|
}
|
|
if pub.X.Cmp(priv.X) != 0 || pub.Y.Cmp(priv.Y) != 0 {
|
|
return fail(errors.New("tls: private key does not match public key"))
|
|
}
|
|
case ed25519.PublicKey:
|
|
priv, ok := cert.PrivateKey.(ed25519.PrivateKey)
|
|
if !ok {
|
|
return fail(errors.New("tls: private key type does not match public key type"))
|
|
}
|
|
if !bytes.Equal(priv.Public().(ed25519.PublicKey), pub) {
|
|
return fail(errors.New("tls: private key does not match public key"))
|
|
}
|
|
default:
|
|
return fail(errors.New("tls: unknown public key algorithm"))
|
|
}
|
|
|
|
return cert, nil
|
|
}
|
|
|
|
// Attempt to parse the given private key DER block. OpenSSL 0.9.8 generates
|
|
// PKCS #1 private keys by default, while OpenSSL 1.0.0 generates PKCS #8 keys.
|
|
// OpenSSL ecparam generates SEC1 EC private keys for ECDSA. We try all three.
|
|
func parsePrivateKey(der []byte) (crypto.PrivateKey, error) {
|
|
if key, err := x509.ParsePKCS1PrivateKey(der); err == nil {
|
|
return key, nil
|
|
}
|
|
if key, err := x509.ParsePKCS8PrivateKey(der); err == nil {
|
|
switch key := key.(type) {
|
|
case *rsa.PrivateKey, *ecdsa.PrivateKey, ed25519.PrivateKey:
|
|
return key, nil
|
|
default:
|
|
return nil, errors.New("tls: found unknown private key type in PKCS#8 wrapping")
|
|
}
|
|
}
|
|
if key, err := x509.ParseECPrivateKey(der); err == nil {
|
|
return key, nil
|
|
}
|
|
|
|
return nil, errors.New("tls: failed to parse private key")
|
|
}
|