Fix draft-14 publish control lengths

Author: mondain

README.md

@@ -199,7 +199,7 @@ Current status as of March 13, 2026:
 - with `--forward 0`, the current client then waits for inbound `SUBSCRIBE_NAMESPACE` / `SUBSCRIBE`
 - the Cloudflare endpoints accepted setup and namespace announce in testing, but did not issue subscriptions, so the publish attempt timed out waiting for control-stream data
 - with `--forward 1`, `moq-relay.red5.net:8443` now progresses through `PUBLISH_OK` for the catalog and media tracks, after which the client begins sending object streams
-- `fb.mvfst.net:9448` accepts QUIC for draft-14 and draft-16, but the current draft-14 flow stalls after namespace acceptance and the current draft-16 flow is still rejected with MOQT application error `3` (`PROTOCOL_VIOLATION`) immediately after setup
+- `fb.mvfst.net:9448` now accepts the draft-14 publish flow end-to-end after switching `PUBLISH`, `PUBLISH_OK`, and `PUBLISH_ERROR` control messages to `u16` outer lengths; the current draft-16 flow is still rejected with MOQT application error `3` (`PROTOCOL_VIOLATION`) immediately after setup
 - `--paced` only affects media-object sends; it does not delay setup, namespace announce, or track publish requests
 
 ### Optional picoquic smoke test

docs/protocol-mapping.md

@@ -7,6 +7,7 @@ This project keeps `draft-ietf-moq-transport-14` as the primary publisher profil
 - Namespace subscription responses are modeled as the dedicated `SUBSCRIBE_NAMESPACE_OK` and `SUBSCRIBE_NAMESPACE_ERROR` flow.
 - Namespace overlap handling is documented against `NAMESPACE_PREFIX_OVERLAP`.
 - Publisher-side namespace acceptance is modeled with draft-14 style `PUBLISH_NAMESPACE_OK` and `PUBLISH_NAMESPACE_ERROR`.
+- Draft-14 control messages use a `u16` outer `Length` field, including `PUBLISH`, `PUBLISH_OK`, and `PUBLISH_ERROR`; only inner fields explicitly marked `(i)` remain QUIC varints.
 
 ## Draft-16 secondary assumptions
 

include/openmoq/publisher/transport/moqt_control_messages.h

@@ -127,6 +127,6 @@ std::vector<std::uint8_t> encode_object_stream(DraftVersion draft,
 bool decode_publish_namespace_ok(std::span<const std::uint8_t> bytes, PublishNamespaceOk& message);
 bool decode_publish_namespace_error(std::span<const std::uint8_t> bytes, PublishNamespaceError& message);
 bool decode_publish_ok(std::span<const std::uint8_t> bytes, DraftVersion draft, PublishOk& message);
-bool decode_publish_error(std::span<const std::uint8_t> bytes, PublishError& message);
+bool decode_publish_error(std::span<const std::uint8_t> bytes, DraftVersion draft, PublishError& message);
 
 }  // namespace openmoq::publisher::transport

src/transport/moqt_control_messages.cpp

@@ -257,8 +257,10 @@ bool next_control_message(std::span<const std::uint8_t> bytes, std::size_t& mess
         case kPublishType:
         case kPublishOkType:
         case kPublishErrorType: {
-            if ((type == kPublishOkType || type == kPublishErrorType || type == kPublishType) &&
-                offset + 2 <= bytes.size() && bytes[offset] == 0) {
+            if (type == kPublishType || type == kPublishOkType || type == kPublishErrorType) {
+                if (offset + 2 > bytes.size()) {
+                    return false;
+                }
                 const std::size_t payload_length =
                     (static_cast<std::size_t>(bytes[offset]) << 8) | static_cast<std::size_t>(bytes[offset + 1]);
                 message_size = offset + 2 + payload_length;
@@ -626,11 +628,7 @@ std::vector<std::uint8_t> encode_track_message(const TrackMessage& message) {
 
     std::vector<std::uint8_t> message_bytes;
     append_varint(message_bytes, kPublishType);
-    if (message.draft == DraftVersion::kDraft14) {
-        append_varint(message_bytes, payload.size());
-    } else {
-        append_uint16(message_bytes, static_cast<std::uint16_t>(payload.size()));
-    }
+    append_uint16(message_bytes, static_cast<std::uint16_t>(payload.size()));
     message_bytes.insert(message_bytes.end(), payload.begin(), payload.end());
     return message_bytes;
 }
@@ -717,10 +715,7 @@ bool decode_publish_namespace_error(std::span<const std::uint8_t> bytes, Publish
 bool decode_publish_ok(std::span<const std::uint8_t> bytes, DraftVersion draft, PublishOk& message) {
     std::size_t payload_offset = 0;
     std::size_t payload_length = 0;
-    const bool parsed =
-        draft == DraftVersion::kDraft14 ? parse_varint_length_message(bytes, kPublishOkType, payload_offset, payload_length)
-                                        : parse_uint16_length_message(bytes, kPublishOkType, payload_offset, payload_length);
-    if (!parsed) {
+    if (!parse_uint16_length_message(bytes, kPublishOkType, payload_offset, payload_length)) {
         return false;
     }
     if (payload_offset + payload_length > bytes.size()) {
@@ -791,10 +786,11 @@ bool decode_publish_ok(std::span<const std::uint8_t> bytes, DraftVersion draft,
     return offset == payload_end;
 }
 
-bool decode_publish_error(std::span<const std::uint8_t> bytes, PublishError& message) {
+bool decode_publish_error(std::span<const std::uint8_t> bytes, DraftVersion draft, PublishError& message) {
+    static_cast<void>(draft);
     std::size_t payload_offset = 0;
     std::size_t payload_length = 0;
-    if (!parse_varint_length_message(bytes, kPublishErrorType, payload_offset, payload_length)) {
+    if (!parse_uint16_length_message(bytes, kPublishErrorType, payload_offset, payload_length)) {
         return false;
     }
     if (payload_offset + payload_length > bytes.size()) {

src/transport/moqt_session.cpp

@@ -137,7 +137,7 @@ void trace_control_message(std::span<const std::uint8_t> message_bytes, openmoq:
         }
     } else if (message_type == 0x1f) {
         PublishError message;
-        if (decode_publish_error(message_bytes, message)) {
+        if (decode_publish_error(message_bytes, draft, message)) {
             std::cerr << " request_id=" << message.request_id << " error_code=" << message.error_code
                       << " reason=" << message.reason;
         }
@@ -262,7 +262,7 @@ TransportStatus collect_control_acknowledgements(PublisherTransport& transport,
                 ++publish_responses;
             } else if (message_type == 0x1f) {
                 PublishError message;
-                if (!decode_publish_error(message_bytes, message)) {
+                if (!decode_publish_error(message_bytes, draft, message)) {
                     return TransportStatus::failure("received invalid PUBLISH_ERROR");
                 }
                 return TransportStatus::failure("peer rejected track publish: " + message.reason);

tests/moqt_session_test.cpp

@@ -208,12 +208,7 @@ std::vector<std::uint8_t> encode_publish_ok_message(DraftVersion draft, std::uin
     }
 
     std::vector<std::uint8_t> message = encode_varint(0x1e);
-    if (draft == DraftVersion::kDraft14) {
-        const std::vector<std::uint8_t> length = encode_varint(payload.size());
-        message.insert(message.end(), length.begin(), length.end());
-    } else {
-        append_be16(message, static_cast<std::uint16_t>(payload.size()));
-    }
+    append_be16(message, static_cast<std::uint16_t>(payload.size()));
     message.insert(message.end(), payload.begin(), payload.end());
     return message;
 }