Add test to check that all settings frames are acked
diff --git a/tools/http2_interop/s6.5.go b/tools/http2_interop/s6.5.go
index 32468ab..4295c46 100644
--- a/tools/http2_interop/s6.5.go
+++ b/tools/http2_interop/s6.5.go
@@ -1,6 +1,7 @@
package http2interop
import (
+ "fmt"
"time"
)
@@ -30,3 +31,60 @@
return nil
}
+
+// Section 6.5.3 says all settings frames must be acked.
+func testAllSettingsFramesAcked(ctx *HTTP2InteropCtx) error {
+ conn, err := connect(ctx)
+ if err != nil {
+ return err
+ }
+ defer conn.Close()
+ conn.SetDeadline(time.Now().Add(defaultTimeout))
+
+ sf := &SettingsFrame{}
+ if err := http2Connect(conn, sf); err != nil {
+ return err
+ }
+
+ // The spec says "The values in the SETTINGS frame MUST be processed in the order they
+ // appear. [...] Once all values have been processed, the recipient MUST immediately
+ // emit a SETTINGS frame with the ACK flag set." From my understanding, processing all
+ // of no values warrants an ack per frame.
+ for i := 0; i < 10; i++ {
+ if err := streamFrame(conn, sf); err != nil {
+ return err
+ }
+ }
+
+ var settingsFramesReceived = 0
+ // The server by default sends a settings frame as part of the handshake, and another
+ // after the receipt of the initial settings frame as part of our conneection preface.
+ // This means we expected 1 + 1 + 10 = 12 settings frames in return, with all but the
+ // first having the ack bit.
+ for settingsFramesReceived < 12 {
+ f, err := parseFrame(conn)
+ if err != nil {
+ return err
+ }
+
+ // Other frames come down the wire too, including window update. Just ignore those.
+ if f, ok := f.(*SettingsFrame); ok {
+ settingsFramesReceived += 1
+ if settingsFramesReceived == 1 {
+ if f.Header.Flags&SETTINGS_FLAG_ACK > 0 {
+ return fmt.Errorf("settings frame should not have used ack: %v")
+ }
+ continue
+ }
+
+ if f.Header.Flags&SETTINGS_FLAG_ACK == 0 {
+ return fmt.Errorf("settings frame should have used ack: %v", f)
+ }
+ if len(f.Params) != 0 {
+ return fmt.Errorf("settings ack cannot have params: %v", f)
+ }
+ }
+ }
+
+ return nil
+}