nghttpx: Add experimental websocket with extended CONNECT

genheaderfunc.py

@@ -9,6 +9,7 @@ HEADERS = [
     ':scheme',
     ':status',
     ':host', # for spdy
+    ':protocol',
     'expect',
     'host',
     'if-modified-since',
@@ -31,6 +32,7 @@ HEADERS = [
     "user-agent",
     "date",
     "content-type",
+    "sec-websocket-accept",
     # disallowed h1 headers
     'connection',
     'keep-alive',

src/http2.cc

@@ -438,6 +438,11 @@ void copy_headers_to_nva_internal(std::vector<nghttp2_nv> &nva,
       kv = &(*it_via);
       it_via = it;
       break;
+    case HD_SEC_WEBSOCKET_ACCEPT:
+      if (flags & HDOP_STRIP_SEC_WEBSOCKET_ACCEPT) {
+        continue;
+      }
+      break;
     }
     nva.push_back(
         make_nv_internal(kv->name, kv->value, kv->no_index, nv_flags));
@@ -821,6 +826,11 @@ int lookup_token(const uint8_t *name, size_t namelen) {
         return HD_FORWARDED;
       }
       break;
+    case 'l':
+      if (util::streq_l(":protoco", name, 8)) {
+        return HD__PROTOCOL;
+      }
+      break;
     }
     break;
   case 10:
@@ -926,6 +936,15 @@ int lookup_token(const uint8_t *name, size_t namelen) {
       break;
     }
     break;
+  case 20:
+    switch (name[19]) {
+    case 't':
+      if (util::streq_l("sec-websocket-accep", name, 19)) {
+        return HD_SEC_WEBSOCKET_ACCEPT;
+      }
+      break;
+    }
+    break;
   }
   return -1;
 }
@@ -1313,7 +1332,8 @@ std::string path_join(const StringRef &base_path, const StringRef &base_query,
 }
 
 bool expect_response_body(int status_code) {
-  return status_code / 100 != 1 && status_code != 304 && status_code != 204;
+  return status_code == 101 ||
+         (status_code / 100 != 1 && status_code != 304 && status_code != 204);
 }
 
 bool expect_response_body(const std::string &method, int status_code) {

src/http2.h

@@ -206,6 +206,8 @@ enum HeaderBuildOp {
   // Strip above all header fields.
   HDOP_STRIP_ALL = HDOP_STRIP_FORWARDED | HDOP_STRIP_X_FORWARDED_FOR |
                    HDOP_STRIP_X_FORWARDED_PROTO | HDOP_STRIP_VIA,
+  // Sec-WebSocket-Accept header field must be stripped.
+  HDOP_STRIP_SEC_WEBSOCKET_ACCEPT = 1 << 4,
 };
 
 // Appends headers in |headers| to |nv|.  |headers| must be indexed
@@ -293,6 +295,7 @@ enum {
   HD__HOST,
   HD__METHOD,
   HD__PATH,
+  HD__PROTOCOL,
   HD__SCHEME,
   HD__STATUS,
   HD_ACCEPT_ENCODING,
@@ -313,6 +316,7 @@ enum {
   HD_LINK,
   HD_LOCATION,
   HD_PROXY_CONNECTION,
+  HD_SEC_WEBSOCKET_ACCEPT,
   HD_SERVER,
   HD_TE,
   HD_TRAILER,

src/shrpx_client_handler.cc

@@ -978,7 +978,7 @@ ClientHandler::get_downstream_connection(int &err, Downstream *downstream) {
     StringRef path;
     // CONNECT method does not have path.  But we requires path in
     // host-path mapping.  As workaround, we assume that path is "/".
-    if (req.method != HTTP_CONNECT) {
+    if (!req.regular_connect_method()) {
       path = req.path;
     }
 

src/shrpx_downstream.cc

@@ -722,7 +722,12 @@ bool Downstream::validate_response_recv_body_length() const {
 
 void Downstream::check_upgrade_fulfilled() {
   if (req_.method == HTTP_CONNECT) {
+    if (req_.connect_proto) {
+      // TODO For websocket, check Sec-WebSocket-Accept header field.
+      upgraded_ = resp_.http_status == 101;
+    } else {
       upgraded_ = 200 <= resp_.http_status && resp_.http_status < 300;
+    }
 
     return;
   }

src/shrpx_downstream.h

@@ -134,6 +134,12 @@ private:
   bool trailer_key_prev_;
 };
 
+// Protocols allowed in HTTP/2 :protocol header field.
+enum shrpx_connect_proto {
+  CONNECT_PROTO_NONE,
+  CONNECT_PROTO_WEBSOCKET,
+};
+
 struct Request {
   Request(BlockAllocator &balloc)
       : fs(balloc, 16),
@@ -153,6 +159,14 @@ struct Request {
     unconsumed_body_length -= len;
   }
 
+  bool regular_connect_method() const {
+    return method == HTTP_CONNECT && !connect_proto;
+  }
+
+  bool extended_connect_method() const {
+    return method == HTTP_CONNECT && connect_proto;
+  }
+
   FieldStore fs;
   // Timestamp when all request header fields are received.
   std::shared_ptr<Timestamp> tstamp;
@@ -176,6 +190,9 @@ struct Request {
   int method;
   // HTTP major and minor version
   int http_major, http_minor;
+  // connect_protocol specified in HTTP/2 :protocol pseudo header
+  // field which enables extended CONNECT method.
+  int connect_proto;
   // Returns true if the request is HTTP upgrade (HTTP Upgrade or
   // CONNECT method).  Upgrade to HTTP/2 is excluded.  For HTTP/2
   // Upgrade, check get_http2_upgrade_request().

src/shrpx_http2_downstream_connection.cc

@@ -250,7 +250,7 @@ int Http2DownstreamConnection::push_request_headers() {
   auto &http2conf = config->http2;
 
   auto no_host_rewrite = httpconf.no_host_rewrite || config->http2_proxy ||
-                         req.method == HTTP_CONNECT;
+                         req.regular_connect_method();
 
   // http2session_ has already in CONNECTED state, so we can get
   // addr_idx here.
@@ -288,7 +288,7 @@ int Http2DownstreamConnection::push_request_headers() {
   nva.push_back(
       http2::make_nv_ls_nocopy(":method", http2::to_method_string(req.method)));
 
-  if (req.method != HTTP_CONNECT) {
+  if (!req.regular_connect_method()) {
     assert(!req.scheme.empty());
 
     auto addr = http2session_->get_addr();
@@ -339,7 +339,7 @@ int Http2DownstreamConnection::push_request_headers() {
   if (fwdconf.params) {
     auto params = fwdconf.params;
 
-    if (config->http2_proxy || req.method == HTTP_CONNECT) {
+    if (config->http2_proxy || req.regular_connect_method()) {
       params &= ~FORWARDED_PROTO;
     }
 
@@ -380,7 +380,7 @@ int Http2DownstreamConnection::push_request_headers() {
     nva.push_back(http2::make_nv_ls_nocopy("x-forwarded-for", xff->value));
   }
 
-  if (!config->http2_proxy && req.method != HTTP_CONNECT) {
+  if (!config->http2_proxy && !req.regular_connect_method()) {
     auto xfp = xfpconf.strip_incoming
                    ? nullptr
                    : req.fs.header(http2::HD_X_FORWARDED_PROTO);

src/shrpx_http2_upstream.cc

@@ -391,6 +391,19 @@ int Http2Upstream::on_request_headers(Downstream *downstream,
     }
   }
 
+  if (!config->http2_proxy) {
+    auto connect_proto = req.fs.header(http2::HD__PROTOCOL);
+    if (connect_proto) {
+      if (connect_proto->value != "websocket") {
+        if (error_reply(downstream, 400) != 0) {
+          return NGHTTP2_ERR_TEMPORAL_CALLBACK_FAILURE;
+        }
+        return 0;
+      }
+      req.connect_proto = CONNECT_PROTO_WEBSOCKET;
+    }
+  }
+
   if (!(frame->hd.flags & NGHTTP2_FLAG_END_STREAM)) {
     req.http2_expect_body = true;
   } else if (req.fs.content_length == -1) {
@@ -1001,8 +1014,8 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
   flow_control_ = true;
 
   // TODO Maybe call from outside?
-  std::array<nghttp2_settings_entry, 3> entry;
+  std::array<nghttp2_settings_entry, 4> entry;
-  size_t nentry = 2;
+  size_t nentry = 3;
 
   entry[0].settings_id = NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS;
   entry[0].value = http2conf.upstream.max_concurrent_streams;
@@ -1014,6 +1027,9 @@ Http2Upstream::Http2Upstream(ClientHandler *handler)
     entry[1].value = http2conf.upstream.window_size;
   }
 
+  entry[2].settings_id = NGHTTP2_SETTINGS_ENABLE_CONNECT_PROTOCOL;
+  entry[2].value = 1;
+
   if (http2conf.upstream.decoder_dynamic_table_size !=
       NGHTTP2_DEFAULT_HEADER_TABLE_SIZE) {
     entry[nentry].settings_id = NGHTTP2_SETTINGS_HEADER_TABLE_SIZE;
@@ -1662,11 +1678,11 @@ int Http2Upstream::on_downstream_header_complete(Downstream *downstream) {
   nva.reserve(resp.fs.headers().size() + 5 +
               httpconf.add_response_headers.size());
 
+  if (downstream->get_non_final_response()) {
     auto response_status = http2::stringify_status(balloc, resp.http_status);
 
     nva.push_back(http2::make_nv_ls_nocopy(":status", response_status));
 
-  if (downstream->get_non_final_response()) {
     http2::copy_headers_to_nva_nocopy(nva, resp.fs.headers(),
                                       http2::HDOP_STRIP_ALL);
 
@@ -1688,8 +1704,19 @@ int Http2Upstream::on_downstream_header_complete(Downstream *downstream) {
     return 0;
   }
 
-  http2::copy_headers_to_nva_nocopy(
+  auto striphd_flags = http2::HDOP_STRIP_ALL & ~http2::HDOP_STRIP_VIA;
-      nva, resp.fs.headers(), http2::HDOP_STRIP_ALL & ~http2::HDOP_STRIP_VIA);
+  StringRef response_status;
+
+  if (req.connect_proto && resp.http_status == 101) {
+    response_status = http2::stringify_status(balloc, 200);
+    striphd_flags |= http2::HDOP_STRIP_SEC_WEBSOCKET_ACCEPT;
+  } else {
+    response_status = http2::stringify_status(balloc, resp.http_status);
+  }
+
+  nva.push_back(http2::make_nv_ls_nocopy(":status", response_status));
+
+  http2::copy_headers_to_nva_nocopy(nva, resp.fs.headers(), striphd_flags);
 
   if (!config->http2_proxy && !httpconf.no_server_rewrite) {
     nva.push_back(http2::make_nv_ls_nocopy("server", httpconf.server_name));
@@ -1700,7 +1727,7 @@ int Http2Upstream::on_downstream_header_complete(Downstream *downstream) {
     }
   }
 
-  if (req.method != HTTP_CONNECT || !downstream->get_upgraded()) {
+  if (!req.regular_connect_method() || !downstream->get_upgraded()) {
     auto affinity_cookie = downstream->get_affinity_cookie_to_send();
     if (affinity_cookie) {
       auto dconn = downstream->get_downstream_connection();
@@ -1874,7 +1901,7 @@ int Http2Upstream::on_downstream_abort_request_with_https_redirect(
 
 int Http2Upstream::redirect_to_https(Downstream *downstream) {
   auto &req = downstream->request();
-  if (req.method == HTTP_CONNECT || req.scheme != "http") {
+  if (req.regular_connect_method() || req.scheme != "http") {
     return error_reply(downstream, 400);
   }
 

src/shrpx_http_downstream_connection.cc

@@ -484,7 +484,7 @@ int HttpDownstreamConnection::push_request_headers() {
 
   auto &balloc = downstream_->get_block_allocator();
 
-  auto connect_method = req.method == HTTP_CONNECT;
+  auto connect_method = req.regular_connect_method();
 
   auto config = get_config();
   auto &httpconf = config->http;
@@ -508,7 +508,8 @@ int HttpDownstreamConnection::push_request_headers() {
   auto buf = downstream_->get_request_buf();
 
   // Assume that method and request path do not contain \r\n.
-  auto meth = http2::to_method_string(req.method);
+  auto meth = http2::to_method_string(
+      req.connect_proto == CONNECT_PROTO_WEBSOCKET ? HTTP_GET : req.method);
   buf->append(meth);
   buf->append(' ');
 
@@ -552,7 +553,8 @@ int HttpDownstreamConnection::push_request_headers() {
 
   // set transfer-encoding only when content-length is unknown and
   // request body is expected.
-  if (!connect_method && req.http2_expect_body && req.fs.content_length == -1) {
+  if (req.method != HTTP_CONNECT && req.http2_expect_body &&
+      req.fs.content_length == -1) {
     downstream_->set_chunked_request(true);
     buf->append("Transfer-Encoding: chunked\r\n");
   }
@@ -561,7 +563,11 @@ int HttpDownstreamConnection::push_request_headers() {
     buf->append("Connection: close\r\n");
   }
 
-  if (!connect_method && req.upgrade_request) {
+  if (req.connect_proto == CONNECT_PROTO_WEBSOCKET) {
+    // TODO Generate Sec-WebSocket-Key
+    buf->append("Upgrade: websocket\r\nConnection: "
+                "Upgrade\r\nSec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ==\r\n");
+  } else if (!connect_method && req.upgrade_request) {
     auto connection = req.fs.header(http2::HD_CONNECTION);
     if (connection) {
       buf->append("Connection: ");
@@ -693,7 +699,7 @@ int HttpDownstreamConnection::push_request_headers() {
   // Don't call signal_write() if we anticipate request body.  We call
   // signal_write() when we received request body chunk, and it
   // enables us to send headers and data in one writev system call.
-  if (connect_method ||
+  if (connect_method || req.connect_proto ||
       (!req.http2_expect_body && req.fs.content_length == 0)) {
     signal_write();
   }
@@ -901,7 +907,7 @@ int htp_hdrs_completecb(http_parser *htp) {
       return -1;
     }
   } else if (resp.http_status / 100 == 1 ||
-             (resp.http_status == 200 && req.method == HTTP_CONNECT)) {
+             (resp.http_status == 200 && req.regular_connect_method())) {
     if (resp.fs.header(http2::HD_CONTENT_LENGTH) ||
         resp.fs.header(http2::HD_TRANSFER_ENCODING)) {
       return -1;