TUN-4597: Add a QUIC server skeleton

- Added a QUIC server to accept streams
- Unit test for this server also tests ALPN
- Temporary echo capability for HTTP ConnectionType

vendor/github.com/marten-seemann/qtls-go1-16/ticket.go

@@ -0,0 +1,259 @@
+// Copyright 2012 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 qtls
+
+import (
+	"bytes"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/hmac"
+	"crypto/sha256"
+	"crypto/subtle"
+	"errors"
+	"io"
+	"time"
+
+	"golang.org/x/crypto/cryptobyte"
+)
+
+// sessionState contains the information that is serialized into a session
+// ticket in order to later resume a connection.
+type sessionState struct {
+	vers         uint16
+	cipherSuite  uint16
+	createdAt    uint64
+	masterSecret []byte // opaque master_secret<1..2^16-1>;
+	// struct { opaque certificate<1..2^24-1> } Certificate;
+	certificates [][]byte // Certificate certificate_list<0..2^24-1>;
+
+	// usedOldKey is true if the ticket from which this session came from
+	// was encrypted with an older key and thus should be refreshed.
+	usedOldKey bool
+}
+
+func (m *sessionState) marshal() []byte {
+	var b cryptobyte.Builder
+	b.AddUint16(m.vers)
+	b.AddUint16(m.cipherSuite)
+	addUint64(&b, m.createdAt)
+	b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddBytes(m.masterSecret)
+	})
+	b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+		for _, cert := range m.certificates {
+			b.AddUint24LengthPrefixed(func(b *cryptobyte.Builder) {
+				b.AddBytes(cert)
+			})
+		}
+	})
+	return b.BytesOrPanic()
+}
+
+func (m *sessionState) unmarshal(data []byte) bool {
+	*m = sessionState{usedOldKey: m.usedOldKey}
+	s := cryptobyte.String(data)
+	if ok := s.ReadUint16(&m.vers) &&
+		s.ReadUint16(&m.cipherSuite) &&
+		readUint64(&s, &m.createdAt) &&
+		readUint16LengthPrefixed(&s, &m.masterSecret) &&
+		len(m.masterSecret) != 0; !ok {
+		return false
+	}
+	var certList cryptobyte.String
+	if !s.ReadUint24LengthPrefixed(&certList) {
+		return false
+	}
+	for !certList.Empty() {
+		var cert []byte
+		if !readUint24LengthPrefixed(&certList, &cert) {
+			return false
+		}
+		m.certificates = append(m.certificates, cert)
+	}
+	return s.Empty()
+}
+
+// sessionStateTLS13 is the content of a TLS 1.3 session ticket. Its first
+// version (revision = 0) doesn't carry any of the information needed for 0-RTT
+// validation and the nonce is always empty.
+// version (revision = 1) carries the max_early_data_size sent in the ticket.
+// version (revision = 2) carries the ALPN sent in the ticket.
+type sessionStateTLS13 struct {
+	// uint8 version  = 0x0304;
+	// uint8 revision = 2;
+	cipherSuite      uint16
+	createdAt        uint64
+	resumptionSecret []byte      // opaque resumption_master_secret<1..2^8-1>;
+	certificate      Certificate // CertificateEntry certificate_list<0..2^24-1>;
+	maxEarlyData     uint32
+	alpn             string
+
+	appData []byte
+}
+
+func (m *sessionStateTLS13) marshal() []byte {
+	var b cryptobyte.Builder
+	b.AddUint16(VersionTLS13)
+	b.AddUint8(2) // revision
+	b.AddUint16(m.cipherSuite)
+	addUint64(&b, m.createdAt)
+	b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddBytes(m.resumptionSecret)
+	})
+	marshalCertificate(&b, m.certificate)
+	b.AddUint32(m.maxEarlyData)
+	b.AddUint8LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddBytes([]byte(m.alpn))
+	})
+	b.AddUint16LengthPrefixed(func(b *cryptobyte.Builder) {
+		b.AddBytes(m.appData)
+	})
+	return b.BytesOrPanic()
+}
+
+func (m *sessionStateTLS13) unmarshal(data []byte) bool {
+	*m = sessionStateTLS13{}
+	s := cryptobyte.String(data)
+	var version uint16
+	var revision uint8
+	var alpn []byte
+	ret := s.ReadUint16(&version) &&
+		version == VersionTLS13 &&
+		s.ReadUint8(&revision) &&
+		revision == 2 &&
+		s.ReadUint16(&m.cipherSuite) &&
+		readUint64(&s, &m.createdAt) &&
+		readUint8LengthPrefixed(&s, &m.resumptionSecret) &&
+		len(m.resumptionSecret) != 0 &&
+		unmarshalCertificate(&s, &m.certificate) &&
+		s.ReadUint32(&m.maxEarlyData) &&
+		readUint8LengthPrefixed(&s, &alpn) &&
+		readUint16LengthPrefixed(&s, &m.appData) &&
+		s.Empty()
+	m.alpn = string(alpn)
+	return ret
+}
+
+func (c *Conn) encryptTicket(state []byte) ([]byte, error) {
+	if len(c.ticketKeys) == 0 {
+		return nil, errors.New("tls: internal error: session ticket keys unavailable")
+	}
+
+	encrypted := make([]byte, ticketKeyNameLen+aes.BlockSize+len(state)+sha256.Size)
+	keyName := encrypted[:ticketKeyNameLen]
+	iv := encrypted[ticketKeyNameLen : ticketKeyNameLen+aes.BlockSize]
+	macBytes := encrypted[len(encrypted)-sha256.Size:]
+
+	if _, err := io.ReadFull(c.config.rand(), iv); err != nil {
+		return nil, err
+	}
+	key := c.ticketKeys[0]
+	copy(keyName, key.keyName[:])
+	block, err := aes.NewCipher(key.aesKey[:])
+	if err != nil {
+		return nil, errors.New("tls: failed to create cipher while encrypting ticket: " + err.Error())
+	}
+	cipher.NewCTR(block, iv).XORKeyStream(encrypted[ticketKeyNameLen+aes.BlockSize:], state)
+
+	mac := hmac.New(sha256.New, key.hmacKey[:])
+	mac.Write(encrypted[:len(encrypted)-sha256.Size])
+	mac.Sum(macBytes[:0])
+
+	return encrypted, nil
+}
+
+func (c *Conn) decryptTicket(encrypted []byte) (plaintext []byte, usedOldKey bool) {
+	if len(encrypted) < ticketKeyNameLen+aes.BlockSize+sha256.Size {
+		return nil, false
+	}
+
+	keyName := encrypted[:ticketKeyNameLen]
+	iv := encrypted[ticketKeyNameLen : ticketKeyNameLen+aes.BlockSize]
+	macBytes := encrypted[len(encrypted)-sha256.Size:]
+	ciphertext := encrypted[ticketKeyNameLen+aes.BlockSize : len(encrypted)-sha256.Size]
+
+	keyIndex := -1
+	for i, candidateKey := range c.ticketKeys {
+		if bytes.Equal(keyName, candidateKey.keyName[:]) {
+			keyIndex = i
+			break
+		}
+	}
+	if keyIndex == -1 {
+		return nil, false
+	}
+	key := &c.ticketKeys[keyIndex]
+
+	mac := hmac.New(sha256.New, key.hmacKey[:])
+	mac.Write(encrypted[:len(encrypted)-sha256.Size])
+	expected := mac.Sum(nil)
+
+	if subtle.ConstantTimeCompare(macBytes, expected) != 1 {
+		return nil, false
+	}
+
+	block, err := aes.NewCipher(key.aesKey[:])
+	if err != nil {
+		return nil, false
+	}
+	plaintext = make([]byte, len(ciphertext))
+	cipher.NewCTR(block, iv).XORKeyStream(plaintext, ciphertext)
+
+	return plaintext, keyIndex > 0
+}
+
+func (c *Conn) getSessionTicketMsg(appData []byte) (*newSessionTicketMsgTLS13, error) {
+	m := new(newSessionTicketMsgTLS13)
+
+	var certsFromClient [][]byte
+	for _, cert := range c.peerCertificates {
+		certsFromClient = append(certsFromClient, cert.Raw)
+	}
+	state := sessionStateTLS13{
+		cipherSuite:      c.cipherSuite,
+		createdAt:        uint64(c.config.time().Unix()),
+		resumptionSecret: c.resumptionSecret,
+		certificate: Certificate{
+			Certificate:                 certsFromClient,
+			OCSPStaple:                  c.ocspResponse,
+			SignedCertificateTimestamps: c.scts,
+		},
+		appData: appData,
+		alpn:    c.clientProtocol,
+	}
+	if c.extraConfig != nil {
+		state.maxEarlyData = c.extraConfig.MaxEarlyData
+	}
+	var err error
+	m.label, err = c.encryptTicket(state.marshal())
+	if err != nil {
+		return nil, err
+	}
+	m.lifetime = uint32(maxSessionTicketLifetime / time.Second)
+	if c.extraConfig != nil {
+		m.maxEarlyData = c.extraConfig.MaxEarlyData
+	}
+	return m, nil
+}
+
+// GetSessionTicket generates a new session ticket.
+// It should only be called after the handshake completes.
+// It can only be used for servers, and only if the alternative record layer is set.
+// The ticket may be nil if config.SessionTicketsDisabled is set,
+// or if the client isn't able to receive session tickets.
+func (c *Conn) GetSessionTicket(appData []byte) ([]byte, error) {
+	if c.isClient || !c.handshakeComplete() || c.extraConfig == nil || c.extraConfig.AlternativeRecordLayer == nil {
+		return nil, errors.New("GetSessionTicket is only valid for servers after completion of the handshake, and if an alternative record layer is set.")
+	}
+	if c.config.SessionTicketsDisabled {
+		return nil, nil
+	}
+
+	m, err := c.getSessionTicketMsg(appData)
+	if err != nil {
+		return nil, err
+	}
+	return m.marshal(), nil
+}