diff --git a/internal/handshake/aead.go b/internal/handshake/aead.go index 693939ae..1baf5d6b 100644 --- a/internal/handshake/aead.go +++ b/internal/handshake/aead.go @@ -1,13 +1,12 @@ package handshake import ( - "crypto/cipher" "encoding/binary" "github.com/quic-go/quic-go/internal/protocol" ) -func createAEAD(suite *cipherSuite, trafficSecret []byte, v protocol.Version) cipher.AEAD { +func createAEAD(suite *cipherSuite, trafficSecret []byte, v protocol.Version) *xorNonceAEAD { keyLabel := hkdfLabelKeyV1 ivLabel := hkdfLabelIVV1 if v == protocol.Version2 { @@ -20,28 +19,26 @@ func createAEAD(suite *cipherSuite, trafficSecret []byte, v protocol.Version) ci } type longHeaderSealer struct { - aead cipher.AEAD + aead *xorNonceAEAD headerProtector headerProtector - - // use a single slice to avoid allocations - nonceBuf []byte + nonceBuf [8]byte } var _ LongHeaderSealer = &longHeaderSealer{} -func newLongHeaderSealer(aead cipher.AEAD, headerProtector headerProtector) LongHeaderSealer { +func newLongHeaderSealer(aead *xorNonceAEAD, headerProtector headerProtector) LongHeaderSealer { + if aead.NonceSize() != 8 { + panic("unexpected nonce size") + } return &longHeaderSealer{ aead: aead, headerProtector: headerProtector, - nonceBuf: make([]byte, aead.NonceSize()), } } func (s *longHeaderSealer) Seal(dst, src []byte, pn protocol.PacketNumber, ad []byte) []byte { - binary.BigEndian.PutUint64(s.nonceBuf[len(s.nonceBuf)-8:], uint64(pn)) - // The AEAD we're using here will be the qtls.aeadAESGCM13. - // It uses the nonce provided here and XOR it with the IV. - return s.aead.Seal(dst, s.nonceBuf, src, ad) + binary.BigEndian.PutUint64(s.nonceBuf[:], uint64(pn)) + return s.aead.Seal(dst, s.nonceBuf[:], src, ad) } func (s *longHeaderSealer) EncryptHeader(sample []byte, firstByte *byte, pnBytes []byte) { @@ -53,21 +50,23 @@ func (s *longHeaderSealer) Overhead() int { } type longHeaderOpener struct { - aead cipher.AEAD + aead *xorNonceAEAD headerProtector headerProtector highestRcvdPN protocol.PacketNumber // highest packet number received (which could be successfully unprotected) - // use a single slice to avoid allocations - nonceBuf []byte + // use a single array to avoid allocations + nonceBuf [8]byte } var _ LongHeaderOpener = &longHeaderOpener{} -func newLongHeaderOpener(aead cipher.AEAD, headerProtector headerProtector) LongHeaderOpener { +func newLongHeaderOpener(aead *xorNonceAEAD, headerProtector headerProtector) LongHeaderOpener { + if aead.NonceSize() != 8 { + panic("unexpected nonce size") + } return &longHeaderOpener{ aead: aead, headerProtector: headerProtector, - nonceBuf: make([]byte, aead.NonceSize()), } } @@ -76,10 +75,8 @@ func (o *longHeaderOpener) DecodePacketNumber(wirePN protocol.PacketNumber, wire } func (o *longHeaderOpener) Open(dst, src []byte, pn protocol.PacketNumber, ad []byte) ([]byte, error) { - binary.BigEndian.PutUint64(o.nonceBuf[len(o.nonceBuf)-8:], uint64(pn)) - // The AEAD we're using here will be the qtls.aeadAESGCM13. - // It uses the nonce provided here and XOR it with the IV. - dec, err := o.aead.Open(dst, o.nonceBuf, src, ad) + binary.BigEndian.PutUint64(o.nonceBuf[:], uint64(pn)) + dec, err := o.aead.Open(dst, o.nonceBuf[:], src, ad) if err == nil { o.highestRcvdPN = max(o.highestRcvdPN, pn) } else { diff --git a/internal/handshake/aead_test.go b/internal/handshake/aead_test.go index 4527e3e1..d2d58a02 100644 --- a/internal/handshake/aead_test.go +++ b/internal/handshake/aead_test.go @@ -33,8 +33,8 @@ var _ = Describe("Long Header AEAD", func() { aead, err := cipher.NewGCM(block) Expect(err).ToNot(HaveOccurred()) - return newLongHeaderSealer(aead, newHeaderProtector(cs, hpKey, true, v)), - newLongHeaderOpener(aead, newHeaderProtector(cs, hpKey, true, v)) + return newLongHeaderSealer(&xorNonceAEAD{aead: aead}, newHeaderProtector(cs, hpKey, true, v)), + newLongHeaderOpener(&xorNonceAEAD{aead: aead}, newHeaderProtector(cs, hpKey, true, v)) } Context("message encryption", func() { diff --git a/internal/handshake/cipher_suite.go b/internal/handshake/cipher_suite.go index 265231f0..d8a381da 100644 --- a/internal/handshake/cipher_suite.go +++ b/internal/handshake/cipher_suite.go @@ -18,7 +18,7 @@ type cipherSuite struct { ID uint16 Hash crypto.Hash KeyLen int - AEAD func(key, nonceMask []byte) cipher.AEAD + AEAD func(key, nonceMask []byte) *xorNonceAEAD } func (s cipherSuite) IVLen() int { return aeadNonceLength } @@ -36,7 +36,7 @@ func getCipherSuite(id uint16) *cipherSuite { } } -func aeadAESGCMTLS13(key, nonceMask []byte) cipher.AEAD { +func aeadAESGCMTLS13(key, nonceMask []byte) *xorNonceAEAD { if len(nonceMask) != aeadNonceLength { panic("tls: internal error: wrong nonce length") } @@ -54,7 +54,7 @@ func aeadAESGCMTLS13(key, nonceMask []byte) cipher.AEAD { return ret } -func aeadChaCha20Poly1305(key, nonceMask []byte) cipher.AEAD { +func aeadChaCha20Poly1305(key, nonceMask []byte) *xorNonceAEAD { if len(nonceMask) != aeadNonceLength { panic("tls: internal error: wrong nonce length") }