src/shrpx_spdy_upstream.cc

   1 /*
   2  * nghttp2 - HTTP/2 C Library
   3  *
   4  * Copyright (c) 2012 Tatsuhiro Tsujikawa
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining
   7  * a copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sublicense, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be
  15  * included in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  20  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  */
  25 #include "shrpx_spdy_upstream.h"
  26
  27 #include <netinet/tcp.h>
  28 #include <assert.h>
  29 #include <cerrno>
  30 #include <sstream>
  31
  32 #include <nghttp2/nghttp2.h>
  33
  34 #include "shrpx_client_handler.h"
  35 #include "shrpx_downstream.h"
  36 #include "shrpx_downstream_connection.h"
  37 #include "shrpx_config.h"
  38 #include "shrpx_http.h"
  39 #include "http2.h"
  40 #include "util.h"
  41 #include "template.h"
  42
  43 using namespace nghttp2;
  44
  45 namespace shrpx {
  46
  47 namespace {
  48 ssize_t send_callback(spdylay_session *session, const uint8_t *data, size_t len,
  49                       int flags, void *user_data) {
  50   auto upstream = static_cast<SpdyUpstream *>(user_data);
  51   auto handler = upstream->get_client_handler();
  52   auto wb = handler->get_wb();
  53
  54   if (wb->wleft() == 0) {
  55     return SPDYLAY_ERR_WOULDBLOCK;
  56   }
  57
  58   auto nread = wb->write(data, len);
  59
  60   return nread;
  61 }
  62 } // namespace
  63
  64 namespace {
  65 ssize_t recv_callback(spdylay_session *session, uint8_t *buf, size_t len,
  66                       int flags, void *user_data) {
  67   auto upstream = static_cast<SpdyUpstream *>(user_data);
  68   auto handler = upstream->get_client_handler();
  69   auto rb = handler->get_rb();
  70   auto rlimit = handler->get_rlimit();
  71
  72   if (rb->rleft() == 0) {
  73     return SPDYLAY_ERR_WOULDBLOCK;
  74   }
  75
  76   auto nread = std::min(rb->rleft(), len);
  77
  78   memcpy(buf, rb->pos, nread);
  79   rb->drain(nread);
  80   rlimit->startw();
  81
  82   return nread;
  83 }
  84 } // namespace
  85
  86 namespace {
  87 void on_stream_close_callback(spdylay_session *session, int32_t stream_id,
  88                               spdylay_status_code status_code,
  89                               void *user_data) {
  90   auto upstream = static_cast<SpdyUpstream *>(user_data);
  91   if (LOG_ENABLED(INFO)) {
  92     ULOG(INFO, upstream) << "Stream stream_id=" << stream_id
  93                          << " is being closed";
  94   }
  95   auto downstream = static_cast<Downstream *>(
  96       spdylay_session_get_stream_user_data(session, stream_id));
  97   if (!downstream) {
  98     return;
  99   }
 100
 101   upstream->consume(stream_id, downstream->get_request_datalen());
 102
 103   downstream->reset_request_datalen();
 104
 105   if (downstream->get_request_state() == Downstream::CONNECT_FAIL) {
 106     upstream->remove_downstream(downstream);
 107     // downstrea was deleted
 108
 109     return;
 110   }
 111
 112   downstream->set_request_state(Downstream::STREAM_CLOSED);
 113   if (downstream->get_response_state() == Downstream::MSG_COMPLETE) {
 114     // At this point, downstream response was read
 115     if (!downstream->get_upgraded() &&
 116         !downstream->get_response_connection_close()) {
 117       // Keep-alive
 118       downstream->detach_downstream_connection();
 119     }
 120     upstream->remove_downstream(downstream);
 121     // downstrea was deleted
 122
 123     return;
 124   }
 125
 126   // At this point, downstream read may be paused.
 127
 128   // If shrpx_downstream::push_request_headers() failed, the
 129   // error is handled here.
 130   upstream->remove_downstream(downstream);
 131   // downstrea was deleted
 132
 133   // How to test this case? Request sufficient large download
 134   // and make client send RST_STREAM after it gets first DATA
 135   // frame chunk.
 136 }
 137 } // namespace
 138
 139 namespace {
 140 void on_ctrl_recv_callback(spdylay_session *session, spdylay_frame_type type,
 141                            spdylay_frame *frame, void *user_data) {
 142   auto upstream = static_cast<SpdyUpstream *>(user_data);
 143   switch (type) {
 144   case SPDYLAY_SYN_STREAM: {
 145     if (LOG_ENABLED(INFO)) {
 146       ULOG(INFO, upstream) << "Received upstream SYN_STREAM stream_id="
 147                            << frame->syn_stream.stream_id;
 148     }
 149
 150     auto downstream = upstream->add_pending_downstream(
 151         frame->syn_stream.stream_id, frame->syn_stream.pri);
 152
 153     downstream->reset_upstream_rtimer();
 154
 155     auto nv = frame->syn_stream.nv;
 156
 157     if (LOG_ENABLED(INFO)) {
 158       std::stringstream ss;
 159       for (size_t i = 0; nv[i]; i += 2) {
 160         ss << TTY_HTTP_HD << nv[i] << TTY_RST << ": " << nv[i + 1] << "\n";
 161       }
 162       ULOG(INFO, upstream) << "HTTP request headers. stream_id="
 163                            << downstream->get_stream_id() << "\n" << ss.str();
 164     }
 165
 166     size_t num_headers = 0;
 167     size_t header_buffer = 0;
 168     for (size_t i = 0; nv[i]; i += 2) {
 169       ++num_headers;
 170       header_buffer += strlen(nv[i]) + strlen(nv[i + 1]);
 171     }
 172
 173     if (header_buffer > get_config()->header_field_buffer ||
 174         num_headers > get_config()->max_header_fields) {
 175       upstream->rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 176       return;
 177     }
 178
 179     for (size_t i = 0; nv[i]; i += 2) {
 180       downstream->add_request_header(nv[i], nv[i + 1]);
 181     }
 182
 183     if (downstream->index_request_headers() != 0) {
 184       if (upstream->error_reply(downstream, 400) != 0) {
 185         ULOG(FATAL, upstream) << "error_reply failed";
 186       }
 187       return;
 188     }
 189
 190     auto path = downstream->get_request_header(http2::HD__PATH);
 191     auto scheme = downstream->get_request_header(http2::HD__SCHEME);
 192     auto host = downstream->get_request_header(http2::HD__HOST);
 193     auto method = downstream->get_request_header(http2::HD__METHOD);
 194
 195     bool is_connect = method && "CONNECT" == method->value;
 196     if (!path || !host || !method || !http2::non_empty_value(host) ||
 197         !http2::non_empty_value(path) || !http2::non_empty_value(method) ||
 198         (!is_connect && (!scheme || !http2::non_empty_value(scheme)))) {
 199       upstream->rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 200       return;
 201     }
 202
 203     downstream->set_request_method(method->value);
 204     if (is_connect) {
 205       downstream->set_request_http2_authority(path->value);
 206     } else {
 207       downstream->set_request_http2_scheme(scheme->value);
 208       downstream->set_request_http2_authority(host->value);
 209       downstream->set_request_path(path->value);
 210     }
 211
 212     if (!(frame->syn_stream.hd.flags & SPDYLAY_CTRL_FLAG_FIN)) {
 213       downstream->set_request_http2_expect_body(true);
 214     }
 215
 216     downstream->inspect_http2_request();
 217
 218     downstream->set_request_state(Downstream::HEADER_COMPLETE);
 219     if (frame->syn_stream.hd.flags & SPDYLAY_CTRL_FLAG_FIN) {
 220       if (!downstream->validate_request_bodylen()) {
 221         upstream->rst_stream(downstream, SPDYLAY_PROTOCOL_ERROR);
 222         return;
 223       }
 224
 225       downstream->disable_upstream_rtimer();
 226       downstream->set_request_state(Downstream::MSG_COMPLETE);
 227     }
 228
 229     upstream->start_downstream(downstream);
 230
 231     break;
 232   }
 233   default:
 234     break;
 235   }
 236 }
 237 } // namespace
 238
 239 void SpdyUpstream::start_downstream(Downstream *downstream) {
 240   if (downstream_queue_.can_activate(
 241           downstream->get_request_http2_authority())) {
 242     initiate_downstream(downstream);
 243     return;
 244   }
 245
 246   downstream_queue_.mark_blocked(downstream);
 247 }
 248
 249 void SpdyUpstream::initiate_downstream(Downstream *downstream) {
 250   int rv = downstream->attach_downstream_connection(
 251       handler_->get_downstream_connection());
 252   if (rv != 0) {
 253     // If downstream connection fails, issue RST_STREAM.
 254     rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 255     downstream->set_request_state(Downstream::CONNECT_FAIL);
 256
 257     downstream_queue_.mark_failure(downstream);
 258
 259     return;
 260   }
 261   rv = downstream->push_request_headers();
 262   if (rv != 0) {
 263     rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 264
 265     downstream_queue_.mark_failure(downstream);
 266
 267     return;
 268   }
 269
 270   downstream_queue_.mark_active(downstream);
 271 }
 272
 273 namespace {
 274 void on_data_chunk_recv_callback(spdylay_session *session, uint8_t flags,
 275                                  int32_t stream_id, const uint8_t *data,
 276                                  size_t len, void *user_data) {
 277   auto upstream = static_cast<SpdyUpstream *>(user_data);
 278   auto downstream = static_cast<Downstream *>(
 279       spdylay_session_get_stream_user_data(session, stream_id));
 280
 281   if (!downstream) {
 282     upstream->consume(stream_id, len);
 283
 284     return;
 285   }
 286
 287   downstream->reset_upstream_rtimer();
 288
 289   if (downstream->push_upload_data_chunk(data, len) != 0) {
 290     upstream->rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 291
 292     upstream->consume(stream_id, len);
 293
 294     return;
 295   }
 296
 297   if (!upstream->get_flow_control()) {
 298     return;
 299   }
 300
 301   // If connection-level window control is not enabled (e.g,
 302   // spdy/3), spdylay_session_get_recv_data_length() is always
 303   // returns 0.
 304   if (spdylay_session_get_recv_data_length(session) >
 305       std::max(SPDYLAY_INITIAL_WINDOW_SIZE,
 306                1 << get_config()->http2_upstream_connection_window_bits)) {
 307     if (LOG_ENABLED(INFO)) {
 308       ULOG(INFO, upstream)
 309           << "Flow control error on connection: "
 310           << "recv_window_size="
 311           << spdylay_session_get_recv_data_length(session) << ", window_size="
 312           << (1 << get_config()->http2_upstream_connection_window_bits);
 313     }
 314     spdylay_session_fail_session(session, SPDYLAY_GOAWAY_PROTOCOL_ERROR);
 315     return;
 316   }
 317   if (spdylay_session_get_stream_recv_data_length(session, stream_id) >
 318       std::max(SPDYLAY_INITIAL_WINDOW_SIZE,
 319                1 << get_config()->http2_upstream_window_bits)) {
 320     if (LOG_ENABLED(INFO)) {
 321       ULOG(INFO, upstream) << "Flow control error: recv_window_size="
 322                            << spdylay_session_get_stream_recv_data_length(
 323                                   session, stream_id)
 324                            << ", initial_window_size="
 325                            << (1 << get_config()->http2_upstream_window_bits);
 326     }
 327     upstream->rst_stream(downstream, SPDYLAY_FLOW_CONTROL_ERROR);
 328     return;
 329   }
 330 }
 331 } // namespace
 332
 333 namespace {
 334 void on_data_recv_callback(spdylay_session *session, uint8_t flags,
 335                            int32_t stream_id, int32_t length, void *user_data) {
 336   auto upstream = static_cast<SpdyUpstream *>(user_data);
 337   auto downstream = static_cast<Downstream *>(
 338       spdylay_session_get_stream_user_data(session, stream_id));
 339   if (downstream && (flags & SPDYLAY_DATA_FLAG_FIN)) {
 340     if (!downstream->validate_request_bodylen()) {
 341       upstream->rst_stream(downstream, SPDYLAY_PROTOCOL_ERROR);
 342       return;
 343     }
 344
 345     downstream->disable_upstream_rtimer();
 346     downstream->end_upload_data();
 347     downstream->set_request_state(Downstream::MSG_COMPLETE);
 348   }
 349 }
 350 } // namespace
 351
 352 namespace {
 353 void on_ctrl_not_send_callback(spdylay_session *session,
 354                                spdylay_frame_type type, spdylay_frame *frame,
 355                                int error_code, void *user_data) {
 356   auto upstream = static_cast<SpdyUpstream *>(user_data);
 357   if (LOG_ENABLED(INFO)) {
 358     ULOG(INFO, upstream) << "Failed to send control frame type=" << type
 359                          << ", error_code=" << error_code << ":"
 360                          << spdylay_strerror(error_code);
 361   }
 362   if (type == SPDYLAY_SYN_REPLY && error_code != SPDYLAY_ERR_STREAM_CLOSED &&
 363       error_code != SPDYLAY_ERR_STREAM_CLOSING) {
 364     // To avoid stream hanging around, issue RST_STREAM.
 365     auto stream_id = frame->syn_reply.stream_id;
 366     // TODO Could be always nullptr
 367     auto downstream = static_cast<Downstream *>(
 368         spdylay_session_get_stream_user_data(session, stream_id));
 369     if (downstream) {
 370       upstream->rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 371     }
 372   }
 373 }
 374 } // namespace
 375
 376 namespace {
 377 void on_ctrl_recv_parse_error_callback(spdylay_session *session,
 378                                        spdylay_frame_type type,
 379                                        const uint8_t *head, size_t headlen,
 380                                        const uint8_t *payload,
 381                                        size_t payloadlen, int error_code,
 382                                        void *user_data) {
 383   auto upstream = static_cast<SpdyUpstream *>(user_data);
 384   if (LOG_ENABLED(INFO)) {
 385     ULOG(INFO, upstream) << "Failed to parse received control frame. type="
 386                          << type << ", error_code=" << error_code << ":"
 387                          << spdylay_strerror(error_code);
 388   }
 389 }
 390 } // namespace
 391
 392 namespace {
 393 void on_unknown_ctrl_recv_callback(spdylay_session *session,
 394                                    const uint8_t *head, size_t headlen,
 395                                    const uint8_t *payload, size_t payloadlen,
 396                                    void *user_data) {
 397   auto upstream = static_cast<SpdyUpstream *>(user_data);
 398   if (LOG_ENABLED(INFO)) {
 399     ULOG(INFO, upstream) << "Received unknown control frame.";
 400   }
 401 }
 402 } // namespace
 403
 404 namespace {
 405 // Infer upstream RST_STREAM status code from downstream HTTP/2
 406 // error code.
 407 uint32_t infer_upstream_rst_stream_status_code(uint32_t downstream_error_code) {
 408   // Only propagate *_REFUSED_STREAM so that upstream client can
 409   // resend request.
 410   if (downstream_error_code == NGHTTP2_REFUSED_STREAM) {
 411     return SPDYLAY_REFUSED_STREAM;
 412   } else {
 413     return SPDYLAY_INTERNAL_ERROR;
 414   }
 415 }
 416 } // namespace
 417
 418 SpdyUpstream::SpdyUpstream(uint16_t version, ClientHandler *handler)
 419     : downstream_queue_(
 420           get_config()->http2_proxy
 421               ? get_config()->downstream_connections_per_host
 422               : get_config()->downstream_proto == PROTO_HTTP
 423                     ? get_config()->downstream_connections_per_frontend
 424                     : 0,
 425           !get_config()->http2_proxy),
 426       handler_(handler), session_(nullptr) {
 427   spdylay_session_callbacks callbacks;
 428   memset(&callbacks, 0, sizeof(callbacks));
 429   callbacks.send_callback = send_callback;
 430   callbacks.recv_callback = recv_callback;
 431   callbacks.on_stream_close_callback = on_stream_close_callback;
 432   callbacks.on_ctrl_recv_callback = on_ctrl_recv_callback;
 433   callbacks.on_data_chunk_recv_callback = on_data_chunk_recv_callback;
 434   callbacks.on_data_recv_callback = on_data_recv_callback;
 435   callbacks.on_ctrl_not_send_callback = on_ctrl_not_send_callback;
 436   callbacks.on_ctrl_recv_parse_error_callback =
 437       on_ctrl_recv_parse_error_callback;
 438   callbacks.on_unknown_ctrl_recv_callback = on_unknown_ctrl_recv_callback;
 439
 440   int rv;
 441   rv = spdylay_session_server_new(&session_, version, &callbacks, this);
 442   assert(rv == 0);
 443
 444   uint32_t max_buffer = 65536;
 445   rv = spdylay_session_set_option(session_,
 446                                   SPDYLAY_OPT_MAX_RECV_CTRL_FRAME_BUFFER,
 447                                   &max_buffer, sizeof(max_buffer));
 448   assert(rv == 0);
 449
 450   if (version >= SPDYLAY_PROTO_SPDY3) {
 451     int val = 1;
 452     flow_control_ = true;
 453     initial_window_size_ = 1 << get_config()->http2_upstream_window_bits;
 454     rv = spdylay_session_set_option(
 455         session_, SPDYLAY_OPT_NO_AUTO_WINDOW_UPDATE2, &val, sizeof(val));
 456     assert(rv == 0);
 457   } else {
 458     flow_control_ = false;
 459     initial_window_size_ = 0;
 460   }
 461   // TODO Maybe call from outside?
 462   std::array<spdylay_settings_entry, 2> entry;
 463   entry[0].settings_id = SPDYLAY_SETTINGS_MAX_CONCURRENT_STREAMS;
 464   entry[0].value = get_config()->http2_max_concurrent_streams;
 465   entry[0].flags = SPDYLAY_ID_FLAG_SETTINGS_NONE;
 466
 467   entry[1].settings_id = SPDYLAY_SETTINGS_INITIAL_WINDOW_SIZE;
 468   entry[1].value = initial_window_size_;
 469   entry[1].flags = SPDYLAY_ID_FLAG_SETTINGS_NONE;
 470
 471   rv = spdylay_submit_settings(session_, SPDYLAY_FLAG_SETTINGS_NONE,
 472                                entry.data(), entry.size());
 473   assert(rv == 0);
 474
 475   if (version >= SPDYLAY_PROTO_SPDY3_1 &&
 476       get_config()->http2_upstream_connection_window_bits > 16) {
 477     int32_t delta = (1 << get_config()->http2_upstream_connection_window_bits) -
 478                     SPDYLAY_INITIAL_WINDOW_SIZE;
 479     rv = spdylay_submit_window_update(session_, 0, delta);
 480     assert(rv == 0);
 481   }
 482
 483   handler_->reset_upstream_read_timeout(
 484       get_config()->http2_upstream_read_timeout);
 485
 486   handler_->signal_write();
 487 }
 488
 489 SpdyUpstream::~SpdyUpstream() { spdylay_session_del(session_); }
 490
 491 int SpdyUpstream::on_read() {
 492   int rv = 0;
 493
 494   rv = spdylay_session_recv(session_);
 495   if (rv < 0) {
 496     if (rv != SPDYLAY_ERR_EOF) {
 497       ULOG(ERROR, this) << "spdylay_session_recv() returned error: "
 498                         << spdylay_strerror(rv);
 499     }
 500     return rv;
 501   }
 502
 503   handler_->signal_write();
 504
 505   return 0;
 506 }
 507
 508 // After this function call, downstream may be deleted.
 509 int SpdyUpstream::on_write() {
 510   int rv = 0;
 511
 512   rv = spdylay_session_send(session_);
 513   if (rv != 0) {
 514     ULOG(ERROR, this) << "spdylay_session_send() returned error: "
 515                       << spdylay_strerror(rv);
 516     return rv;
 517   }
 518
 519   if (spdylay_session_want_read(session_) == 0 &&
 520       spdylay_session_want_write(session_) == 0 &&
 521       handler_->get_wb()->rleft() == 0) {
 522     if (LOG_ENABLED(INFO)) {
 523       ULOG(INFO, this) << "No more read/write for this SPDY session";
 524     }
 525     return -1;
 526   }
 527   return 0;
 528 }
 529
 530 ClientHandler *SpdyUpstream::get_client_handler() const { return handler_; }
 531
 532 int SpdyUpstream::downstream_read(DownstreamConnection *dconn) {
 533   auto downstream = dconn->get_downstream();
 534
 535   if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
 536     // If upstream SPDY stream was closed, we just close downstream,
 537     // because there is no consumer now. Downstream connection is also
 538     // closed in this case.
 539     remove_downstream(downstream);
 540     // downstrea was deleted
 541
 542     return 0;
 543   }
 544
 545   if (downstream->get_response_state() == Downstream::MSG_RESET) {
 546     // The downstream stream was reset (canceled). In this case,
 547     // RST_STREAM to the upstream and delete downstream connection
 548     // here. Deleting downstream will be taken place at
 549     // on_stream_close_callback.
 550     rst_stream(downstream,
 551                infer_upstream_rst_stream_status_code(
 552                    downstream->get_response_rst_stream_error_code()));
 553     downstream->pop_downstream_connection();
 554     dconn = nullptr;
 555   } else if (downstream->get_response_state() == Downstream::MSG_BAD_HEADER) {
 556     if (error_reply(downstream, 502) != 0) {
 557       return -1;
 558     }
 559     downstream->pop_downstream_connection();
 560     // dconn was deleted
 561     dconn = nullptr;
 562   } else {
 563     auto rv = downstream->on_read();
 564     if (rv == SHRPX_ERR_EOF) {
 565       return downstream_eof(dconn);
 566     }
 567     if (rv != 0) {
 568       if (rv != SHRPX_ERR_NETWORK) {
 569         if (LOG_ENABLED(INFO)) {
 570           DCLOG(INFO, dconn) << "HTTP parser failure";
 571         }
 572       }
 573       return downstream_error(dconn, Downstream::EVENT_ERROR);
 574     }
 575     // Detach downstream connection early so that it could be reused
 576     // without hitting server's request timeout.
 577     if (downstream->get_response_state() == Downstream::MSG_COMPLETE &&
 578         !downstream->get_response_connection_close()) {
 579       // Keep-alive
 580       downstream->detach_downstream_connection();
 581     }
 582   }
 583
 584   handler_->signal_write();
 585   // At this point, downstream may be deleted.
 586
 587   return 0;
 588 }
 589
 590 int SpdyUpstream::downstream_write(DownstreamConnection *dconn) {
 591   int rv;
 592   rv = dconn->on_write();
 593   if (rv == SHRPX_ERR_NETWORK) {
 594     return downstream_error(dconn, Downstream::EVENT_ERROR);
 595   }
 596   if (rv != 0) {
 597     return -1;
 598   }
 599   return 0;
 600 }
 601
 602 int SpdyUpstream::downstream_eof(DownstreamConnection *dconn) {
 603   auto downstream = dconn->get_downstream();
 604
 605   if (LOG_ENABLED(INFO)) {
 606     DCLOG(INFO, dconn) << "EOF. stream_id=" << downstream->get_stream_id();
 607   }
 608   if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
 609     // If stream was closed already, we don't need to send reply at
 610     // the first place. We can delete downstream.
 611     remove_downstream(downstream);
 612     // downstream was deleted
 613
 614     return 0;
 615   }
 616
 617   // Delete downstream connection. If we don't delete it here, it will
 618   // be pooled in on_stream_close_callback.
 619   downstream->pop_downstream_connection();
 620   // dconn was deleted
 621   dconn = nullptr;
 622   // downstream wil be deleted in on_stream_close_callback.
 623   if (downstream->get_response_state() == Downstream::HEADER_COMPLETE) {
 624     // Server may indicate the end of the request by EOF
 625     if (LOG_ENABLED(INFO)) {
 626       ULOG(INFO, this) << "Downstream body was ended by EOF";
 627     }
 628     downstream->set_response_state(Downstream::MSG_COMPLETE);
 629
 630     // For tunneled connection, MSG_COMPLETE signals
 631     // downstream_data_read_callback to send RST_STREAM after pending
 632     // response body is sent. This is needed to ensure that RST_STREAM
 633     // is sent after all pending data are sent.
 634     on_downstream_body_complete(downstream);
 635   } else if (downstream->get_response_state() != Downstream::MSG_COMPLETE) {
 636     // If stream was not closed, then we set MSG_COMPLETE and let
 637     // on_stream_close_callback delete downstream.
 638     if (error_reply(downstream, 502) != 0) {
 639       return -1;
 640     }
 641   }
 642   handler_->signal_write();
 643   // At this point, downstream may be deleted.
 644   return 0;
 645 }
 646
 647 int SpdyUpstream::downstream_error(DownstreamConnection *dconn, int events) {
 648   auto downstream = dconn->get_downstream();
 649
 650   if (LOG_ENABLED(INFO)) {
 651     if (events & Downstream::EVENT_ERROR) {
 652       DCLOG(INFO, dconn) << "Downstream network/general error";
 653     } else {
 654       DCLOG(INFO, dconn) << "Timeout";
 655     }
 656     if (downstream->get_upgraded()) {
 657       DCLOG(INFO, dconn) << "Note: this is tunnel connection";
 658     }
 659   }
 660
 661   if (downstream->get_request_state() == Downstream::STREAM_CLOSED) {
 662     remove_downstream(downstream);
 663     // downstream was deleted
 664
 665     return 0;
 666   }
 667
 668   // Delete downstream connection. If we don't delete it here, it will
 669   // be pooled in on_stream_close_callback.
 670   downstream->pop_downstream_connection();
 671   // dconn was deleted
 672   dconn = nullptr;
 673
 674   if (downstream->get_response_state() == Downstream::MSG_COMPLETE) {
 675     // For SSL tunneling, we issue RST_STREAM. For other types of
 676     // stream, we don't have to do anything since response was
 677     // complete.
 678     if (downstream->get_upgraded()) {
 679       // We want "NO_ERROR" error code but SPDY does not have such
 680       // code for RST_STREAM.
 681       rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 682     }
 683   } else {
 684     if (downstream->get_response_state() == Downstream::HEADER_COMPLETE) {
 685       if (downstream->get_upgraded()) {
 686         on_downstream_body_complete(downstream);
 687       } else {
 688         rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
 689       }
 690     } else {
 691       unsigned int status;
 692       if (events & Downstream::EVENT_TIMEOUT) {
 693         status = 504;
 694       } else {
 695         status = 502;
 696       }
 697       if (error_reply(downstream, status) != 0) {
 698         return -1;
 699       }
 700     }
 701     downstream->set_response_state(Downstream::MSG_COMPLETE);
 702   }
 703   handler_->signal_write();
 704   // At this point, downstream may be deleted.
 705   return 0;
 706 }
 707
 708 int SpdyUpstream::rst_stream(Downstream *downstream, int status_code) {
 709   if (LOG_ENABLED(INFO)) {
 710     ULOG(INFO, this) << "RST_STREAM stream_id=" << downstream->get_stream_id();
 711   }
 712   int rv;
 713   rv = spdylay_submit_rst_stream(session_, downstream->get_stream_id(),
 714                                  status_code);
 715   if (rv < SPDYLAY_ERR_FATAL) {
 716     ULOG(FATAL, this) << "spdylay_submit_rst_stream() failed: "
 717                       << spdylay_strerror(rv);
 718     DIE();
 719   }
 720   return 0;
 721 }
 722
 723 namespace {
 724 ssize_t spdy_data_read_callback(spdylay_session *session, int32_t stream_id,
 725                                 uint8_t *buf, size_t length, int *eof,
 726                                 spdylay_data_source *source, void *user_data) {
 727   auto downstream = static_cast<Downstream *>(source->ptr);
 728   auto upstream = static_cast<SpdyUpstream *>(downstream->get_upstream());
 729   auto body = downstream->get_response_buf();
 730   assert(body);
 731
 732   auto dconn = downstream->get_downstream_connection();
 733
 734   if (body->rleft() == 0 && dconn &&
 735       downstream->get_response_state() != Downstream::MSG_COMPLETE) {
 736     // Try to read more if buffer is empty.  This will help small
 737     // buffer and make priority handling a bit better.
 738     if (upstream->downstream_read(dconn) != 0) {
 739       return SPDYLAY_ERR_CALLBACK_FAILURE;
 740     }
 741   }
 742
 743   auto nread = body->remove(buf, length);
 744   auto body_empty = body->rleft() == 0;
 745
 746   if (nread == 0 &&
 747       downstream->get_response_state() == Downstream::MSG_COMPLETE) {
 748     if (!downstream->get_upgraded()) {
 749       *eof = 1;
 750     } else {
 751       // For tunneling, issue RST_STREAM to finish the stream.
 752       if (LOG_ENABLED(INFO)) {
 753         ULOG(INFO, upstream)
 754             << "RST_STREAM to tunneled stream stream_id=" << stream_id;
 755       }
 756       upstream->rst_stream(
 757           downstream, infer_upstream_rst_stream_status_code(
 758                           downstream->get_response_rst_stream_error_code()));
 759     }
 760   }
 761
 762   if (body_empty) {
 763     downstream->disable_upstream_wtimer();
 764   } else {
 765     downstream->reset_upstream_wtimer();
 766   }
 767
 768   if (nread > 0 && downstream->resume_read(SHRPX_NO_BUFFER, nread) != 0) {
 769     return SPDYLAY_ERR_CALLBACK_FAILURE;
 770   }
 771
 772   if (nread == 0 && *eof != 1) {
 773     return SPDYLAY_ERR_DEFERRED;
 774   }
 775
 776   if (nread > 0) {
 777     downstream->add_response_sent_bodylen(nread);
 778   }
 779
 780   return nread;
 781 }
 782 } // namespace
 783
 784 int SpdyUpstream::error_reply(Downstream *downstream,
 785                               unsigned int status_code) {
 786   int rv;
 787   auto html = http::create_error_html(status_code);
 788   downstream->set_response_http_status(status_code);
 789   auto body = downstream->get_response_buf();
 790   body->append(html.c_str(), html.size());
 791   downstream->set_response_state(Downstream::MSG_COMPLETE);
 792
 793   spdylay_data_provider data_prd;
 794   data_prd.source.ptr = downstream;
 795   data_prd.read_callback = spdy_data_read_callback;
 796
 797   std::string content_length = util::utos(html.size());
 798   std::string status_string = http2::get_status_string(status_code);
 799   const char *nv[] = {":status",        status_string.c_str(),
 800                       ":version",       "http/1.1",
 801                       "content-type",   "text/html; charset=UTF-8",
 802                       "server",         get_config()->server_name,
 803                       "content-length", content_length.c_str(),
 804                       nullptr};
 805
 806   rv = spdylay_submit_response(session_, downstream->get_stream_id(), nv,
 807                                &data_prd);
 808   if (rv < SPDYLAY_ERR_FATAL) {
 809     ULOG(FATAL, this) << "spdylay_submit_response() failed: "
 810                       << spdylay_strerror(rv);
 811     return -1;
 812   }
 813
 814   return 0;
 815 }
 816
 817 Downstream *SpdyUpstream::add_pending_downstream(int32_t stream_id,
 818                                                  int32_t priority) {
 819   auto downstream = make_unique<Downstream>(this, handler_->get_mcpool(),
 820                                             stream_id, priority);
 821   spdylay_session_set_stream_user_data(session_, stream_id, downstream.get());
 822   auto res = downstream.get();
 823
 824   downstream_queue_.add_pending(std::move(downstream));
 825
 826   return res;
 827 }
 828
 829 void SpdyUpstream::remove_downstream(Downstream *downstream) {
 830   if (downstream->accesslog_ready()) {
 831     handler_->write_accesslog(downstream);
 832   }
 833
 834   spdylay_session_set_stream_user_data(session_, downstream->get_stream_id(),
 835                                        nullptr);
 836
 837   auto next_downstream = downstream_queue_.remove_and_get_blocked(downstream);
 838
 839   if (next_downstream) {
 840     initiate_downstream(next_downstream);
 841   }
 842 }
 843
 844 // WARNING: Never call directly or indirectly spdylay_session_send or
 845 // spdylay_session_recv. These calls may delete downstream.
 846 int SpdyUpstream::on_downstream_header_complete(Downstream *downstream) {
 847   if (downstream->get_non_final_response()) {
 848     // SPDY does not support non-final response.  We could send it
 849     // with HEADERS and final response in SYN_REPLY, but it is not
 850     // official way.
 851     downstream->clear_response_headers();
 852
 853     return 0;
 854   }
 855
 856   if (LOG_ENABLED(INFO)) {
 857     DLOG(INFO, downstream) << "HTTP response header completed";
 858   }
 859
 860   if (!get_config()->http2_proxy && !get_config()->client_proxy &&
 861       !get_config()->no_location_rewrite) {
 862     downstream->rewrite_location_response_header(
 863         downstream->get_request_http2_scheme());
 864   }
 865   size_t nheader = downstream->get_response_headers().size();
 866   // 8 means server, :status, :version and possible via header field.
 867   auto nv = make_unique<const char *[]>(
 868       nheader * 2 + 8 + get_config()->add_response_headers.size() * 2 + 1);
 869
 870   size_t hdidx = 0;
 871   std::string via_value;
 872   std::string status_string =
 873       http2::get_status_string(downstream->get_response_http_status());
 874   nv[hdidx++] = ":status";
 875   nv[hdidx++] = status_string.c_str();
 876   nv[hdidx++] = ":version";
 877   nv[hdidx++] = "HTTP/1.1";
 878   for (auto &hd : downstream->get_response_headers()) {
 879     if (hd.name.empty() || hd.name.c_str()[0] == ':') {
 880       continue;
 881     }
 882     switch (hd.token) {
 883     case http2::HD_CONNECTION:
 884     case http2::HD_KEEP_ALIVE:
 885     case http2::HD_PROXY_CONNECTION:
 886     case http2::HD_TRANSFER_ENCODING:
 887     case http2::HD_VIA:
 888     case http2::HD_SERVER:
 889       continue;
 890     }
 891
 892     nv[hdidx++] = hd.name.c_str();
 893     nv[hdidx++] = hd.value.c_str();
 894   }
 895
 896   if (!get_config()->http2_proxy && !get_config()->client_proxy) {
 897     nv[hdidx++] = "server";
 898     nv[hdidx++] = get_config()->server_name;
 899   } else {
 900     auto server = downstream->get_response_header(http2::HD_SERVER);
 901     if (server) {
 902       nv[hdidx++] = "server";
 903       nv[hdidx++] = server->value.c_str();
 904     }
 905   }
 906
 907   auto via = downstream->get_response_header(http2::HD_VIA);
 908   if (get_config()->no_via) {
 909     if (via) {
 910       nv[hdidx++] = "via";
 911       nv[hdidx++] = via->value.c_str();
 912     }
 913   } else {
 914     if (via) {
 915       via_value = via->value;
 916       via_value += ", ";
 917     }
 918     via_value += http::create_via_header_value(
 919         downstream->get_response_major(), downstream->get_response_minor());
 920     nv[hdidx++] = "via";
 921     nv[hdidx++] = via_value.c_str();
 922   }
 923
 924   for (auto &p : get_config()->add_response_headers) {
 925     nv[hdidx++] = p.first.c_str();
 926     nv[hdidx++] = p.second.c_str();
 927   }
 928
 929   nv[hdidx++] = 0;
 930   if (LOG_ENABLED(INFO)) {
 931     std::stringstream ss;
 932     for (size_t i = 0; nv[i]; i += 2) {
 933       ss << TTY_HTTP_HD << nv[i] << TTY_RST << ": " << nv[i + 1] << "\n";
 934     }
 935     ULOG(INFO, this) << "HTTP response headers. stream_id="
 936                      << downstream->get_stream_id() << "\n" << ss.str();
 937   }
 938   spdylay_data_provider data_prd;
 939   data_prd.source.ptr = downstream;
 940   data_prd.read_callback = spdy_data_read_callback;
 941
 942   int rv;
 943   rv = spdylay_submit_response(session_, downstream->get_stream_id(), nv.get(),
 944                                &data_prd);
 945   if (rv != 0) {
 946     ULOG(FATAL, this) << "spdylay_submit_response() failed";
 947     return -1;
 948   }
 949
 950   return 0;
 951 }
 952
 953 // WARNING: Never call directly or indirectly spdylay_session_send or
 954 // spdylay_session_recv. These calls may delete downstream.
 955 int SpdyUpstream::on_downstream_body(Downstream *downstream,
 956                                      const uint8_t *data, size_t len,
 957                                      bool flush) {
 958   auto body = downstream->get_response_buf();
 959   body->append(data, len);
 960
 961   if (flush) {
 962     spdylay_session_resume_data(session_, downstream->get_stream_id());
 963
 964     downstream->ensure_upstream_wtimer();
 965   }
 966
 967   return 0;
 968 }
 969
 970 // WARNING: Never call directly or indirectly spdylay_session_send or
 971 // spdylay_session_recv. These calls may delete downstream.
 972 int SpdyUpstream::on_downstream_body_complete(Downstream *downstream) {
 973   if (LOG_ENABLED(INFO)) {
 974     DLOG(INFO, downstream) << "HTTP response completed";
 975   }
 976
 977   if (!downstream->validate_response_bodylen()) {
 978     rst_stream(downstream, SPDYLAY_PROTOCOL_ERROR);
 979     downstream->set_response_connection_close(true);
 980     return 0;
 981   }
 982
 983   spdylay_session_resume_data(session_, downstream->get_stream_id());
 984   downstream->ensure_upstream_wtimer();
 985
 986   return 0;
 987 }
 988
 989 bool SpdyUpstream::get_flow_control() const { return flow_control_; }
 990
 991 void SpdyUpstream::pause_read(IOCtrlReason reason) {}
 992
 993 int SpdyUpstream::resume_read(IOCtrlReason reason, Downstream *downstream,
 994                               size_t consumed) {
 995   if (get_flow_control()) {
 996     assert(downstream->get_request_datalen() >= consumed);
 997
 998     if (consume(downstream->get_stream_id(), consumed) != 0) {
 999       return -1;
1000     }
1001
1002     downstream->dec_request_datalen(consumed);
1003   }
1004
1005   handler_->signal_write();
1006   return 0;
1007 }
1008
1009 int SpdyUpstream::on_downstream_abort_request(Downstream *downstream,
1010                                               unsigned int status_code) {
1011   int rv;
1012
1013   rv = error_reply(downstream, status_code);
1014
1015   if (rv != 0) {
1016     return -1;
1017   }
1018
1019   handler_->signal_write();
1020   return 0;
1021 }
1022
1023 int SpdyUpstream::consume(int32_t stream_id, size_t len) {
1024   int rv;
1025
1026   rv = spdylay_session_consume(session_, stream_id, len);
1027
1028   if (rv != 0) {
1029     ULOG(WARN, this) << "spdylay_session_consume() returned error: "
1030                      << spdylay_strerror(rv);
1031     return -1;
1032   }
1033
1034   return 0;
1035 }
1036
1037 int SpdyUpstream::on_timeout(Downstream *downstream) {
1038   if (LOG_ENABLED(INFO)) {
1039     ULOG(INFO, this) << "Stream timeout stream_id="
1040                      << downstream->get_stream_id();
1041   }
1042
1043   rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
1044
1045   return 0;
1046 }
1047
1048 void SpdyUpstream::on_handler_delete() {
1049   for (auto d = downstream_queue_.get_downstreams(); d; d = d->dlnext) {
1050     if (d->get_dispatch_state() == Downstream::DISPATCH_ACTIVE &&
1051         d->accesslog_ready()) {
1052       handler_->write_accesslog(d);
1053     }
1054   }
1055 }
1056
1057 int SpdyUpstream::on_downstream_reset(bool no_retry) {
1058   int rv;
1059
1060   for (auto downstream = downstream_queue_.get_downstreams(); downstream;
1061        downstream = downstream->dlnext) {
1062     if (downstream->get_dispatch_state() != Downstream::DISPATCH_ACTIVE) {
1063       continue;
1064     }
1065
1066     if (!downstream->request_submission_ready()) {
1067       rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
1068       downstream->pop_downstream_connection();
1069       continue;
1070     }
1071
1072     downstream->pop_downstream_connection();
1073
1074     downstream->add_retry();
1075
1076     if (no_retry || downstream->no_more_retry()) {
1077       goto fail;
1078     }
1079
1080     // downstream connection is clean; we can retry with new
1081     // downstream connection.
1082
1083     rv = downstream->attach_downstream_connection(
1084         handler_->get_downstream_connection());
1085     if (rv != 0) {
1086       goto fail;
1087     }
1088
1089     continue;
1090
1091   fail:
1092     if (on_downstream_abort_request(downstream, 503) != 0) {
1093       return -1;
1094     }
1095     downstream->pop_downstream_connection();
1096   }
1097
1098   handler_->signal_write();
1099
1100   return 0;
1101 }
1102
1103 } // namespace shrpx