Send a GREASE capsule immediately after datagram visitor registration.
PiperOrigin-RevId: 401377746
diff --git a/quic/core/http/quic_spdy_stream.cc b/quic/core/http/quic_spdy_stream.cc
index 98422e0..c25d33a 100644
--- a/quic/core/http/quic_spdy_stream.cc
+++ b/quic/core/http/quic_spdy_stream.cc
@@ -1447,6 +1447,21 @@
WriteOrBufferBody(serialized_capsule.AsStringView(), /*fin=*/fin);
}
+void QuicSpdyStream::WriteGreaseCapsule() {
+ // GREASE capsulde IDs have a form of 41 * N + 23.
+ QuicRandom* random = spdy_session_->connection()->random_generator();
+ uint64_t type = random->InsecureRandUint64() >> 4;
+ type = (type / 41) * 41 + 23;
+ QUICHE_DCHECK_EQ((type - 23) % 41, 0u);
+
+ constexpr size_t kMaxLength = 64;
+ size_t length = random->InsecureRandUint64() % kMaxLength;
+ std::string bytes(length, '\0');
+ random->InsecureRandBytes(&bytes[0], bytes.size());
+ Capsule capsule = Capsule::Unknown(type, bytes);
+ WriteCapsule(capsule, /*fin=*/false);
+}
+
MessageStatus QuicSpdyStream::SendHttp3Datagram(
absl::optional<QuicDatagramContextId> context_id,
absl::string_view payload) {
@@ -1557,12 +1572,19 @@
if (context_id.has_value()) {
const bool is_client_context = context_id.value() % 2 == 0;
if (is_client == is_client_context) {
+ QuicConnection::ScopedPacketFlusher flusher(
+ spdy_session_->connection());
+ WriteGreaseCapsule();
WriteCapsule(Capsule::RegisterDatagramContext(
context_id.value(), format_type, format_additional_data));
+ WriteGreaseCapsule();
}
} else if (is_client) {
+ QuicConnection::ScopedPacketFlusher flusher(spdy_session_->connection());
+ WriteGreaseCapsule();
WriteCapsule(Capsule::RegisterDatagramNoContext(format_type,
format_additional_data));
+ WriteGreaseCapsule();
}
}
}
diff --git a/quic/core/http/quic_spdy_stream.h b/quic/core/http/quic_spdy_stream.h
index 6a9f71f..7ea2d1d 100644
--- a/quic/core/http/quic_spdy_stream.h
+++ b/quic/core/http/quic_spdy_stream.h
@@ -345,6 +345,8 @@
// Writes |capsule| onto the DATA stream.
void WriteCapsule(const Capsule& capsule, bool fin = false);
+ void WriteGreaseCapsule();
+
protected:
// Called when the received headers are too large. By default this will
// reset the stream.
