1 files changed, 356 insertions, 0 deletions
diff --git a/src/crypto/tls/tls.go b/src/crypto/tls/tls.go
new file mode 100644
index 0000000..b529c70
--- /dev/null
+++ b/src/crypto/tls/tls.go
@@ -0,0 +1,356 @@
+// 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"
+)
+
+// 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.
+//
+// DialWithDialer uses context.Background internally; to specify the context,
+// use Dialer.DialContext with NetDialer set to the desired dialer.
+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) {
+	if netDialer.Timeout != 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, netDialer.Timeout)
+		defer cancel()
+	}
+
+	if !netDialer.Deadline.IsZero() {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithDeadline(ctx, netDialer.Deadline)
+		defer cancel()
+	}
+
+	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 err := conn.HandshakeContext(ctx); 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.
+//
+// Dial uses context.Background internally; to specify the context,
+// use DialContext.
+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")
+}