send the transport parameters in the TLS handshake

internal/handshake/params_negotiator.go

@@ -0,0 +1,109 @@
+package handshake
+
+import (
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"math"
+	"time"
+
+	"github.com/lucas-clemente/quic-go/internal/protocol"
+	"github.com/lucas-clemente/quic-go/internal/utils"
+)
+
+type paramsNegotiator struct {
+	paramsNegotiatorBase
+}
+
+var _ ParamsNegotiator = &paramsNegotiator{}
+
+// newParamsNegotiator creates a new connection parameters manager
+func newParamsNegotiator(pers protocol.Perspective, v protocol.VersionNumber, params *TransportParameters) *paramsNegotiator {
+	h := &paramsNegotiator{}
+	h.perspective = pers
+	h.version = v
+	h.init(params)
+	return h
+}
+
+func (h *paramsNegotiator) SetFromTransportParameters(params []transportParameter) error {
+	h.mutex.Lock()
+	defer h.mutex.Unlock()
+
+	var foundInitialMaxStreamData bool
+	var foundInitialMaxData bool
+	var foundInitialMaxStreamID bool
+	var foundIdleTimeout bool
+
+	for _, p := range params {
+		switch p.Parameter {
+		case initialMaxStreamDataParameterID:
+			foundInitialMaxStreamData = true
+			if len(p.Value) != 4 {
+				return fmt.Errorf("wrong length for initial_max_stream_data: %d (expected 4)", len(p.Value))
+			}
+			h.sendStreamFlowControlWindow = protocol.ByteCount(binary.BigEndian.Uint32(p.Value))
+			utils.Debugf("h.sendStreamFlowControlWindow: %#x", h.sendStreamFlowControlWindow)
+		case initialMaxDataParameterID:
+			foundInitialMaxData = true
+			if len(p.Value) != 4 {
+				return fmt.Errorf("wrong length for initial_max_data: %d (expected 4)", len(p.Value))
+			}
+			h.sendConnectionFlowControlWindow = protocol.ByteCount(binary.BigEndian.Uint32(p.Value))
+			utils.Debugf("h.sendConnectionFlowControlWindow: %#x", h.sendConnectionFlowControlWindow)
+		case initialMaxStreamIDParameterID:
+			foundInitialMaxStreamID = true
+			if len(p.Value) != 4 {
+				return fmt.Errorf("wrong length for initial_max_stream_id: %d (expected 4)", len(p.Value))
+			}
+			// TODO: handle this value
+		case idleTimeoutParameterID:
+			foundIdleTimeout = true
+			if len(p.Value) != 2 {
+				return fmt.Errorf("wrong length for idle_timeout: %d (expected 2)", len(p.Value))
+			}
+			val := time.Duration(binary.BigEndian.Uint16(p.Value)) * time.Second
+			h.idleConnectionStateLifetime = h.negotiateIdleConnectionStateLifetime(val)
+		case omitConnectionIDParameterID:
+			if len(p.Value) != 0 {
+				return fmt.Errorf("wrong length for omit_connection_id: %d (expected empty)", len(p.Value))
+			}
+			h.truncateConnectionID = true
+		}
+	}
+
+	if !(foundInitialMaxStreamData && foundInitialMaxData && foundInitialMaxStreamID && foundIdleTimeout) {
+		return errors.New("missing parameter")
+	}
+	return nil
+}
+
+func (h *paramsNegotiator) GetTransportParameters() []transportParameter {
+	initialMaxStreamData := make([]byte, 4)
+	binary.BigEndian.PutUint32(initialMaxStreamData, uint32(h.GetReceiveStreamFlowControlWindow()))
+	initialMaxData := make([]byte, 4)
+	binary.BigEndian.PutUint32(initialMaxData, uint32(h.GetReceiveConnectionFlowControlWindow()))
+	initialMaxStreamID := make([]byte, 4)
+	// TODO: use a reasonable value here
+	binary.BigEndian.PutUint32(initialMaxStreamID, math.MaxUint32)
+	idleTimeout := make([]byte, 2)
+	binary.BigEndian.PutUint16(idleTimeout, uint16(h.GetIdleConnectionStateLifetime().Seconds()))
+	params := []transportParameter{
+		{initialMaxStreamDataParameterID, initialMaxStreamData},
+		{initialMaxDataParameterID, initialMaxData},
+		{initialMaxStreamIDParameterID, initialMaxStreamID},
+		{idleTimeoutParameterID, idleTimeout},
+	}
+	h.mutex.RLock()
+	defer h.mutex.RUnlock()
+	if h.truncateConnectionID {
+		params = append(params, transportParameter{omitConnectionIDParameterID, []byte{}})
+	}
+	return params
+}
+
+func (h *paramsNegotiator) TruncateConnectionID() bool {
+	h.mutex.RLock()
+	defer h.mutex.RUnlock()
+	return h.truncateConnectionID
+}