analyzer: make http3/quic handling more reliable

analyzer/udp/internal/quic/payload_test.go

@@ -0,0 +1,39 @@
+package quic
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestExtractCryptoFrames_Interleaved(t *testing.T) {
+	// PADDING, CRYPTO(offset=0,"abc"), PING, STREAM(len=2), CRYPTO(offset=3,"de")
+	payload := []byte{
+		0x00,
+		0x06, 0x00, 0x03, 'a', 'b', 'c',
+		0x01,
+		0x0a, 0x01, 0x02, 'z', 'z',
+		0x06, 0x03, 0x02, 'd', 'e',
+	}
+
+	frames, err := extractCryptoFrames(bytes.NewReader(payload))
+	if err != nil {
+		t.Fatalf("extractCryptoFrames() error = %v", err)
+	}
+	if len(frames) != 2 {
+		t.Fatalf("extractCryptoFrames() len = %d, want 2", len(frames))
+	}
+	if frames[0].Offset != 0 || string(frames[0].Data) != "abc" {
+		t.Fatalf("frame0 = %+v, want offset=0 data=abc", frames[0])
+	}
+	if frames[1].Offset != 3 || string(frames[1].Data) != "de" {
+		t.Fatalf("frame1 = %+v, want offset=3 data=de", frames[1])
+	}
+}
+
+func TestExtractCryptoFrames_UnsupportedFrame(t *testing.T) {
+	// 0x20 is currently unsupported in this parser.
+	_, err := extractCryptoFrames(bytes.NewReader([]byte{0x20}))
+	if err == nil {
+		t.Fatal("extractCryptoFrames() error = nil, want non-nil")
+	}
+}