diff --git a/internal/handshake/aead.go b/internal/handshake/aead.go
index 6ba2d561..673544e2 100644
--- a/internal/handshake/aead.go
+++ b/internal/handshake/aead.go
@@ -1,10 +1,13 @@
 package handshake
 
 import (
+	"crypto/aes"
 	"crypto/cipher"
 	"encoding/binary"
+	"fmt"
 
 	"github.com/lucas-clemente/quic-go/internal/protocol"
+	"github.com/marten-seemann/qtls"
 )
 
 type sealer struct {
@@ -86,3 +89,14 @@ func (o *longHeaderOpener) DecryptHeader(sample []byte, firstByte *byte, pnBytes
 		pnBytes[i] ^= o.hpMask[i+1]
 	}
 }
+
+func createAEAD(suite cipherSuite, trafficSecret []byte) (cipher.AEAD, cipher.Block) {
+	key := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic key", suite.KeyLen())
+	iv := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic iv", suite.IVLen())
+	hpKey := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic hp", suite.KeyLen())
+	hpDecrypter, err := aes.NewCipher(hpKey)
+	if err != nil {
+		panic(fmt.Sprintf("error creating new AES cipher: %s", err))
+	}
+	return suite.AEAD(key, iv), hpDecrypter
+}
diff --git a/internal/handshake/crypto_setup.go b/internal/handshake/crypto_setup.go
index 48c9bc4f..086e46b6 100644
--- a/internal/handshake/crypto_setup.go
+++ b/internal/handshake/crypto_setup.go
@@ -1,7 +1,6 @@
 package handshake
 
 import (
-	"crypto/aes"
 	"crypto/tls"
 	"errors"
 	"fmt"
@@ -483,23 +482,15 @@ func (h *cryptoSetup) ReadHandshakeMessage() ([]byte, error) {
 }
 
 func (h *cryptoSetup) SetReadKey(suite *qtls.CipherSuite, trafficSecret []byte) {
-	key := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic key", suite.KeyLen())
-	iv := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic iv", suite.IVLen())
-	hpKey := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic hp", suite.KeyLen())
-	hpDecrypter, err := aes.NewCipher(hpKey)
-	if err != nil {
-		panic(fmt.Sprintf("error creating new AES cipher: %s", err))
-	}
-
 	h.mutex.Lock()
 	switch h.readEncLevel {
 	case protocol.EncryptionInitial:
 		h.readEncLevel = protocol.EncryptionHandshake
-		h.handshakeOpener = newLongHeaderOpener(suite.AEAD(key, iv), hpDecrypter)
+		h.handshakeOpener = newLongHeaderOpener(createAEAD(suite, trafficSecret))
 		h.logger.Debugf("Installed Handshake Read keys")
 	case protocol.EncryptionHandshake:
 		h.readEncLevel = protocol.Encryption1RTT
-		h.aead.SetReadKey(suite.AEAD(key, iv), hpDecrypter)
+		h.aead.SetReadKey(suite, trafficSecret)
 		h.has1RTTOpener = true
 		h.logger.Debugf("Installed 1-RTT Read keys")
 	default:
@@ -510,23 +501,15 @@ func (h *cryptoSetup) SetReadKey(suite *qtls.CipherSuite, trafficSecret []byte)
 }
 
 func (h *cryptoSetup) SetWriteKey(suite *qtls.CipherSuite, trafficSecret []byte) {
-	key := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic key", suite.KeyLen())
-	iv := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic iv", suite.IVLen())
-	hpKey := qtls.HkdfExpandLabel(suite.Hash(), trafficSecret, []byte{}, "quic hp", suite.KeyLen())
-	hpEncrypter, err := aes.NewCipher(hpKey)
-	if err != nil {
-		panic(fmt.Sprintf("error creating new AES cipher: %s", err))
-	}
-
 	h.mutex.Lock()
 	switch h.writeEncLevel {
 	case protocol.EncryptionInitial:
 		h.writeEncLevel = protocol.EncryptionHandshake
-		h.handshakeSealer = newLongHeaderSealer(suite.AEAD(key, iv), hpEncrypter)
+		h.handshakeSealer = newLongHeaderSealer(createAEAD(suite, trafficSecret))
 		h.logger.Debugf("Installed Handshake Write keys")
 	case protocol.EncryptionHandshake:
 		h.writeEncLevel = protocol.Encryption1RTT
-		h.aead.SetWriteKey(suite.AEAD(key, iv), hpEncrypter)
+		h.aead.SetWriteKey(suite, trafficSecret)
 		h.has1RTTSealer = true
 		h.logger.Debugf("Installed 1-RTT Write keys")
 	default:
diff --git a/internal/handshake/qtls.go b/internal/handshake/qtls.go
index cd093142..52d0723f 100644
--- a/internal/handshake/qtls.go
+++ b/internal/handshake/qtls.go
@@ -1,6 +1,8 @@
 package handshake
 
 import (
+	"crypto"
+	"crypto/cipher"
 	"crypto/tls"
 	"net"
 	"time"
@@ -9,6 +11,13 @@ import (
 	"github.com/marten-seemann/qtls"
 )
 
+type cipherSuite interface {
+	Hash() crypto.Hash
+	KeyLen() int
+	IVLen() int
+	AEAD(key, nonce []byte) cipher.AEAD
+}
+
 type conn struct {
 	remoteAddr net.Addr
 }
diff --git a/internal/handshake/updatable_aead.go b/internal/handshake/updatable_aead.go
index 591f6677..1943da0c 100644
--- a/internal/handshake/updatable_aead.go
+++ b/internal/handshake/updatable_aead.go
@@ -84,10 +84,10 @@ func newUpdatableAEAD() *updatableAEAD {
 	return &updatableAEAD{}
 }
 
-func (a *updatableAEAD) SetReadKey(aead cipher.AEAD, hpDecrypter cipher.Block) {
-	a.ShortHeaderOpener = newShortHeaderOpener(aead, hpDecrypter)
+func (a *updatableAEAD) SetReadKey(suite cipherSuite, trafficSecret []byte) {
+	a.ShortHeaderOpener = newShortHeaderOpener(createAEAD(suite, trafficSecret))
 }
 
-func (a *updatableAEAD) SetWriteKey(aead cipher.AEAD, hpDecrypter cipher.Block) {
-	a.ShortHeaderSealer = newShortHeaderSealer(aead, hpDecrypter)
+func (a *updatableAEAD) SetWriteKey(suite cipherSuite, trafficSecret []byte) {
+	a.ShortHeaderSealer = newShortHeaderSealer(createAEAD(suite, trafficSecret))
 }
diff --git a/internal/handshake/updatable_aead_test.go b/internal/handshake/updatable_aead_test.go
index 19edd02a..05626de1 100644
--- a/internal/handshake/updatable_aead_test.go
+++ b/internal/handshake/updatable_aead_test.go
@@ -1,6 +1,7 @@
 package handshake
 
 import (
+	"crypto"
 	"crypto/aes"
 	"crypto/cipher"
 	"crypto/rand"
@@ -10,25 +11,29 @@ import (
 	. "github.com/onsi/gomega"
 )
 
+type mockCipherSuite struct{}
+
+var _ cipherSuite = &mockCipherSuite{}
+
+func (c *mockCipherSuite) Hash() crypto.Hash { return crypto.SHA256 }
+func (c *mockCipherSuite) KeyLen() int       { return 16 }
+func (c *mockCipherSuite) IVLen() int        { return 12 }
+func (c *mockCipherSuite) AEAD(key, _ []byte) cipher.AEAD {
+	block, err := aes.NewCipher(key)
+	Expect(err).ToNot(HaveOccurred())
+	gcm, err := cipher.NewGCM(block)
+	Expect(err).ToNot(HaveOccurred())
+	return gcm
+}
+
 var _ = Describe("Updatable AEAD", func() {
 	getAEAD := func() *updatableAEAD {
-		key := make([]byte, 16)
-		hpKey := make([]byte, 16)
-		rand.Read(key)
-		rand.Read(hpKey)
-		block, err := aes.NewCipher(key)
-		Expect(err).ToNot(HaveOccurred())
-		aead, err := cipher.NewGCM(block)
-		Expect(err).ToNot(HaveOccurred())
-		hpBlock, err := aes.NewCipher(hpKey)
-		Expect(err).ToNot(HaveOccurred())
-
-		iv := make([]byte, 12)
-		rand.Read(iv)
+		trafficSecret := make([]byte, 16)
+		rand.Read(trafficSecret)
 
 		u := newUpdatableAEAD()
-		u.SetReadKey(aead, hpBlock)
-		u.SetWriteKey(aead, hpBlock)
+		u.SetReadKey(&mockCipherSuite{}, trafficSecret)
+		u.SetWriteKey(&mockCipherSuite{}, trafficSecret)
 		return u
 	}