5 #include <netinet/in.h>
6 #include <netinet/tcp.h>
12 #include <sys/epoll.h>
13 #include <sys/sendfile.h>
14 #include <sys/socket.h>
15 #include <sys/types.h>
27 #include "accesslog.h"
29 #include "metacube2.h"
36 #ifndef SO_MAX_PACING_RATE
37 #define SO_MAX_PACING_RATE 47
42 extern AccessLogThread *access_log;
46 inline bool is_equal(timespec a, timespec b)
48 return a.tv_sec == b.tv_sec &&
49 a.tv_nsec == b.tv_nsec;
52 inline bool is_earlier(timespec a, timespec b)
54 if (a.tv_sec != b.tv_sec)
55 return a.tv_sec < b.tv_sec;
56 return a.tv_nsec < b.tv_nsec;
63 epoll_fd = epoll_create(1024); // Size argument is ignored.
65 log_perror("epoll_fd");
75 vector<ClientStats> Server::get_client_stats() const
77 vector<ClientStats> ret;
79 lock_guard<mutex> lock(mu);
80 for (const auto &fd_and_client : clients) {
81 ret.push_back(fd_and_client.second.get_stats());
86 vector<HLSZombie> Server::get_hls_zombies()
88 vector<HLSZombie> ret;
91 if (clock_gettime(CLOCK_MONOTONIC_COARSE, &now) == -1) {
92 log_perror("clock_gettime(CLOCK_MONOTONIC_COARSE)");
96 lock_guard<mutex> lock(mu);
97 for (auto it = hls_zombies.begin(); it != hls_zombies.end(); ) {
98 if (is_earlier(it->second.expires, now)) {
99 hls_zombies.erase(it++);
101 ret.push_back(it->second);
108 void Server::do_work()
110 while (!should_stop()) {
111 // Wait until there's activity on at least one of the fds,
112 // or 20 ms (about one frame at 50 fps) has elapsed.
114 // We could in theory wait forever and rely on wakeup()
115 // from add_client_deferred() and add_data_deferred(),
116 // but wakeup is a pretty expensive operation, and the
117 // two threads might end up fighting over a lock, so it's
118 // seemingly (much) more efficient to just have a timeout here.
119 int nfds = epoll_pwait(epoll_fd, events, EPOLL_MAX_EVENTS, EPOLL_TIMEOUT_MS, &sigset_without_usr1_block);
120 if (nfds == -1 && errno != EINTR) {
121 log_perror("epoll_wait");
125 lock_guard<mutex> lock(mu); // We release the mutex between iterations.
127 process_queued_data();
129 // Process each client where we have socket activity.
130 for (int i = 0; i < nfds; ++i) {
131 Client *client = reinterpret_cast<Client *>(events[i].data.ptr);
133 if (events[i].events & (EPOLLERR | EPOLLRDHUP | EPOLLHUP)) {
134 close_client(client);
138 process_client(client);
141 // Process each client where its stream has new data,
142 // even if there was no socket activity.
143 for (unique_ptr<Stream> &stream : streams) {
144 vector<Client *> to_process;
145 swap(stream->to_process, to_process);
146 for (Client *client : to_process) {
147 process_client(client);
151 // Finally, go through each client to see if it's timed out
152 // in the READING_REQUEST state. (Seemingly there are clients
153 // that can hold sockets up for days at a time without sending
155 timespec timeout_time;
156 if (clock_gettime(CLOCK_MONOTONIC_COARSE, &timeout_time) == -1) {
157 log_perror("clock_gettime(CLOCK_MONOTONIC_COARSE)");
160 timeout_time.tv_sec -= REQUEST_READ_TIMEOUT_SEC;
161 while (!clients_ordered_by_connect_time.empty()) {
162 const pair<timespec, int> &connect_time_and_fd = clients_ordered_by_connect_time.front();
164 // See if we have reached the end of clients to process.
165 if (is_earlier(timeout_time, connect_time_and_fd.first)) {
169 // If this client doesn't exist anymore, just ignore it
170 // (it was deleted earlier).
171 auto client_it = clients.find(connect_time_and_fd.second);
172 if (client_it == clients.end()) {
173 clients_ordered_by_connect_time.pop();
176 Client *client = &client_it->second;
177 if (!is_equal(client->connect_time, connect_time_and_fd.first)) {
178 // Another client has taken this fd in the meantime.
179 clients_ordered_by_connect_time.pop();
183 if (client->state != Client::READING_REQUEST) {
184 // Only READING_REQUEST can time out.
185 clients_ordered_by_connect_time.pop();
190 close_client(client);
191 clients_ordered_by_connect_time.pop();
196 CubemapStateProto Server::serialize(unordered_map<const string *, size_t> *short_response_pool)
198 // We don't serialize anything queued, so empty the queues.
199 process_queued_data();
201 // Set all clients in a consistent state before serializing
202 // (ie., they have no remaining lost data). Otherwise, increasing
203 // the backlog could take clients into a newly valid area of the backlog,
204 // sending a stream of zeros instead of skipping the data as it should.
206 // TODO: Do this when clients are added back from serialized state instead;
207 // it would probably be less wasteful.
208 for (auto &fd_and_client : clients) {
209 skip_lost_data(&fd_and_client.second);
212 CubemapStateProto serialized;
213 for (const auto &fd_and_client : clients) {
214 serialized.add_clients()->MergeFrom(fd_and_client.second.serialize(short_response_pool));
216 for (unique_ptr<Stream> &stream : streams) {
217 serialized.add_streams()->MergeFrom(stream->serialize());
219 for (const auto &key_and_zombie : hls_zombies) {
220 HLSZombieProto *proto = serialized.add_hls_zombies();
221 proto->set_key(key_and_zombie.first);
223 const HLSZombie &zombie = key_and_zombie.second;
224 proto->set_remote_addr(zombie.remote_addr);
225 proto->set_url(zombie.url);
226 proto->set_referer(zombie.referer);
227 proto->set_user_agent(zombie.user_agent);
228 proto->set_expires_sec(zombie.expires.tv_sec);
229 proto->set_expires_nsec(zombie.expires.tv_nsec);
234 void Server::add_client_deferred(int sock, Acceptor *acceptor)
236 lock_guard<mutex> lock(queued_clients_mutex);
237 queued_add_clients.push_back(std::make_pair(sock, acceptor));
240 void Server::add_client(int sock, Acceptor *acceptor)
242 const bool is_tls = acceptor->is_tls();
243 auto inserted = clients.insert(make_pair(sock, Client(sock)));
244 assert(inserted.second == true); // Should not already exist.
245 Client *client_ptr = &inserted.first->second;
247 start_client_timeout_timer(client_ptr);
249 // Start listening on data from this socket.
252 // Even in the initial state (READING_REQUEST), TLS needs to
253 // send data for the handshake, and thus might end up needing
254 // to know about EPOLLOUT.
255 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLRDHUP;
257 // EPOLLOUT will be added once we go out of READING_REQUEST.
258 ev.events = EPOLLIN | EPOLLET | EPOLLRDHUP;
260 ev.data.ptr = client_ptr;
261 if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sock, &ev) == -1) {
262 log_perror("epoll_ctl(EPOLL_CTL_ADD)");
267 assert(tls_server_contexts.count(acceptor));
268 client_ptr->tls_context = tls_accept(tls_server_contexts[acceptor]);
269 if (client_ptr->tls_context == nullptr) {
270 log(ERROR, "tls_accept() failed");
271 close_client(client_ptr);
274 tls_make_exportable(client_ptr->tls_context, 1);
277 process_client(client_ptr);
280 void Server::add_client_from_serialized(const ClientProto &client, const vector<shared_ptr<const string>> &short_responses)
282 lock_guard<mutex> lock(mu);
284 int stream_index = lookup_stream_by_url(client.url());
285 if (stream_index == -1) {
286 assert(client.state() != Client::SENDING_DATA);
289 stream = streams[stream_index].get();
291 auto inserted = clients.insert(make_pair(client.sock(), Client(client, short_responses, stream)));
292 assert(inserted.second == true); // Should not already exist.
293 Client *client_ptr = &inserted.first->second;
295 // Connection timestamps must be nondecreasing.
296 assert(clients_ordered_by_connect_time.empty() ||
297 !is_earlier(client_ptr->connect_time, clients_ordered_by_connect_time.back().first));
298 clients_ordered_by_connect_time.push(make_pair(client_ptr->connect_time, client.sock()));
300 // Start listening on data from this socket.
302 if (client.state() == Client::READING_REQUEST) {
303 // See the corresponding comment in Server::add_client().
304 if (client.has_tls_context()) {
305 ev.events = EPOLLIN | EPOLLOUT | EPOLLET | EPOLLRDHUP;
307 ev.events = EPOLLIN | EPOLLET | EPOLLRDHUP;
310 // If we don't have more data for this client, we'll be putting it into
311 // the sleeping array again soon.
312 ev.events = EPOLLOUT | EPOLLET | EPOLLRDHUP;
314 ev.data.ptr = client_ptr;
315 if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, client.sock(), &ev) == -1) {
316 log_perror("epoll_ctl(EPOLL_CTL_ADD)");
320 if (client_ptr->state == Client::WAITING_FOR_KEYFRAME ||
321 client_ptr->state == Client::PREBUFFERING ||
322 (client_ptr->state == Client::SENDING_DATA &&
323 client_ptr->stream_pos == client_ptr->stream->bytes_received)) {
324 client_ptr->stream->put_client_to_sleep(client_ptr);
326 process_client(client_ptr);
330 void Server::start_client_timeout_timer(Client *client)
332 // Connection timestamps must be nondecreasing. I can't find any guarantee
333 // that even the monotonic clock can't go backwards by a small amount
334 // (think switching between CPUs with non-synchronized TSCs), so if
335 // this actually should happen, we hack around it by fudging
337 if (clock_gettime(CLOCK_MONOTONIC_COARSE, &client->connect_time) == -1) {
338 log_perror("clock_gettime(CLOCK_MONOTONIC_COARSE)");
340 if (!clients_ordered_by_connect_time.empty() &&
341 is_earlier(client->connect_time, clients_ordered_by_connect_time.back().first)) {
342 client->connect_time = clients_ordered_by_connect_time.back().first;
344 clients_ordered_by_connect_time.push(make_pair(client->connect_time, client->sock));
348 int Server::lookup_stream_by_url(const string &url) const
350 const auto stream_url_it = stream_url_map.find(url);
351 if (stream_url_it == stream_url_map.end()) {
354 return stream_url_it->second;
357 int Server::add_stream(const string &url,
358 const string &hls_url,
360 size_t prebuffering_bytes,
361 Stream::Encoding encoding,
362 Stream::Encoding src_encoding,
363 unsigned hls_frag_duration,
364 size_t hls_backlog_margin,
365 const string &allow_origin)
367 lock_guard<mutex> lock(mu);
368 stream_url_map.insert(make_pair(url, streams.size()));
369 if (!hls_url.empty()) {
370 stream_hls_url_map.insert(make_pair(hls_url, streams.size()));
372 streams.emplace_back(new Stream(url, backlog_size, prebuffering_bytes, encoding, src_encoding, hls_frag_duration, hls_backlog_margin, allow_origin));
373 return streams.size() - 1;
376 int Server::add_stream_from_serialized(const StreamProto &stream, int data_fd)
378 lock_guard<mutex> lock(mu);
379 stream_url_map.insert(make_pair(stream.url(), streams.size()));
380 // stream_hls_url_map will be updated in register_hls_url(), since it is not part
381 // of the serialized state (it will always be picked out from the configuration).
382 streams.emplace_back(new Stream(stream, data_fd));
383 return streams.size() - 1;
386 void Server::add_hls_zombie_from_serialized(const HLSZombieProto &zombie_proto)
388 lock_guard<mutex> lock(mu);
390 zombie.remote_addr = zombie_proto.remote_addr();
391 zombie.url = zombie_proto.url();
392 zombie.referer = zombie_proto.referer();
393 zombie.user_agent = zombie_proto.user_agent();
394 zombie.expires.tv_sec = zombie_proto.expires_sec();
395 zombie.expires.tv_nsec = zombie_proto.expires_nsec();
396 hls_zombies[zombie_proto.key()] = move(zombie);
399 void Server::set_backlog_size(int stream_index, size_t new_size)
401 lock_guard<mutex> lock(mu);
402 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
403 streams[stream_index]->set_backlog_size(new_size);
406 void Server::set_prebuffering_bytes(int stream_index, size_t new_amount)
408 lock_guard<mutex> lock(mu);
409 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
410 streams[stream_index]->prebuffering_bytes = new_amount;
413 void Server::set_encoding(int stream_index, Stream::Encoding encoding)
415 lock_guard<mutex> lock(mu);
416 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
417 streams[stream_index]->encoding = encoding;
420 void Server::set_src_encoding(int stream_index, Stream::Encoding encoding)
422 lock_guard<mutex> lock(mu);
423 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
424 streams[stream_index]->src_encoding = encoding;
427 void Server::set_hls_frag_duration(int stream_index, unsigned hls_frag_duration)
429 lock_guard<mutex> lock(mu);
430 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
431 streams[stream_index]->hls_frag_duration = hls_frag_duration;
434 void Server::set_hls_backlog_margin(int stream_index, size_t hls_backlog_margin)
436 lock_guard<mutex> lock(mu);
437 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
438 assert(hls_backlog_margin < streams[stream_index]->backlog_size);
439 streams[stream_index]->hls_backlog_margin = hls_backlog_margin;
442 void Server::set_allow_origin(int stream_index, const string &allow_origin)
444 lock_guard<mutex> lock(mu);
445 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
446 streams[stream_index]->allow_origin = allow_origin;
449 void Server::register_hls_url(int stream_index, const string &hls_url)
451 lock_guard<mutex> lock(mu);
452 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
453 assert(!hls_url.empty());
454 stream_hls_url_map.insert(make_pair(hls_url, stream_index));
457 void Server::set_header(int stream_index, const string &http_header, const string &stream_header)
459 lock_guard<mutex> lock(mu);
460 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
461 streams[stream_index]->set_header(http_header, stream_header);
464 void Server::set_unavailable(int stream_index)
466 lock_guard<mutex> lock(mu);
467 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
468 streams[stream_index]->set_unavailable();
471 void Server::set_pacing_rate(int stream_index, uint32_t pacing_rate)
473 lock_guard<mutex> lock(mu);
474 assert(clients.empty());
475 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
476 streams[stream_index]->pacing_rate = pacing_rate;
479 void Server::add_gen204(const std::string &url, const std::string &allow_origin)
481 lock_guard<mutex> lock(mu);
482 assert(clients.empty());
483 ping_url_map[url] = allow_origin;
486 void Server::create_tls_context_for_acceptor(const Acceptor *acceptor)
488 assert(acceptor->is_tls());
490 bool is_server = true;
491 TLSContext *server_context = tls_create_context(is_server, TLS_V12);
493 const string &cert = acceptor->get_certificate_chain();
494 int num_cert = tls_load_certificates(server_context, reinterpret_cast<const unsigned char *>(cert.data()), cert.size());
495 assert(num_cert > 0); // Should have been checked by config earlier.
497 const string &key = acceptor->get_private_key();
498 int num_key = tls_load_private_key(server_context, reinterpret_cast<const unsigned char *>(key.data()), key.size());
499 assert(num_key > 0); // Should have been checked by config earlier.
501 tls_server_contexts.insert(make_pair(acceptor, server_context));
504 void Server::add_data_deferred(int stream_index, const char *data, size_t bytes, uint16_t metacube_flags, const RationalPTS &pts)
506 assert(stream_index >= 0 && stream_index < ssize_t(streams.size()));
507 streams[stream_index]->add_data_deferred(data, bytes, metacube_flags, pts);
510 // See the .h file for postconditions after this function.
511 void Server::process_client(Client *client)
513 switch (client->state) {
514 case Client::READING_REQUEST: {
515 if (client->tls_context != nullptr && !client->in_ktls_mode) {
516 if (send_pending_tls_data(client)) {
517 // send_pending_tls_data() hit postconditions #1 or #4.
523 // Try to read more of the request.
526 if (client->tls_context == nullptr || client->in_ktls_mode) {
527 ret = read_plain_data(client, buf, sizeof(buf));
529 // read_plain_data() hit postconditions #1 or #2.
533 ret = read_tls_data(client, buf, sizeof(buf));
535 // read_tls_data() hit postconditions #1, #2 or #4.
540 RequestParseStatus status = wait_for_double_newline(&client->request, buf, ret);
543 case RP_OUT_OF_SPACE:
544 log(WARNING, "[%s] Client sent overlong request!", client->remote_addr.c_str());
545 close_client(client);
547 case RP_NOT_FINISHED_YET:
548 // OK, we don't have the entire header yet. Fine; we'll get it later.
549 // See if there's more data for us.
550 goto read_request_again;
552 log(WARNING, "[%s] Junk data after request!", client->remote_addr.c_str());
553 close_client(client);
559 assert(status == RP_FINISHED);
561 int error_code = parse_request(client);
562 if (error_code == 200) {
563 if (client->serving_hls_playlist) {
564 construct_hls_playlist(client);
566 construct_stream_header(client);
568 } else if (error_code == 204) {
569 construct_204(client);
571 construct_error(client, error_code);
574 // We've changed states, so fall through.
575 assert(client->state == Client::SENDING_SHORT_RESPONSE ||
576 client->state == Client::SENDING_HEADER);
578 case Client::SENDING_SHORT_RESPONSE:
579 case Client::SENDING_HEADER: {
580 sending_header_or_short_response_again:
583 ret = write(client->sock,
584 client->header_or_short_response->data() + client->header_or_short_response_bytes_sent,
585 client->header_or_short_response->size() - client->header_or_short_response_bytes_sent);
586 } while (ret == -1 && errno == EINTR);
588 if (ret == -1 && errno == EAGAIN) {
589 // We're out of socket space, so now we're at the “low edge” of epoll's
590 // edge triggering. epoll will tell us when there is more room, so for now,
592 // This is postcondition #4.
597 // Error! Postcondition #1.
599 close_client(client);
603 client->header_or_short_response_bytes_sent += ret;
604 assert(client->header_or_short_response_bytes_sent <= client->header_or_short_response->size());
606 if (client->header_or_short_response_bytes_sent < client->header_or_short_response->size()) {
607 // We haven't sent all yet. Fine; go another round.
608 goto sending_header_or_short_response_again;
611 // We're done sending the header or error! Clear it to release some memory.
612 client->header_or_short_response = nullptr;
613 client->header_or_short_response_holder.clear();
614 client->header_or_short_response_ref.reset();
616 if (client->state == Client::SENDING_SHORT_RESPONSE) {
617 if (more_requests(client)) {
618 // We're done sending the error, but should keep on reading new requests.
619 goto read_request_again;
621 // We're done sending the error, so now close.
622 // This is postcondition #1.
623 close_client(client);
628 Stream *stream = client->stream;
629 hls_zombies.erase(client->get_hls_zombie_key());
630 if (client->stream_pos == Client::STREAM_POS_AT_START) {
631 // Start sending from the beginning of the backlog.
632 client->stream_pos = min<size_t>(
633 stream->bytes_received - stream->backlog_size,
635 client->state = Client::SENDING_DATA;
637 } else if (client->stream_pos_end != Client::STREAM_POS_NO_END) {
638 // We're sending a fragment, and should have all of it,
639 // so start sending right away.
640 assert(ssize_t(client->stream_pos) >= 0);
641 client->state = Client::SENDING_DATA;
643 } else if (stream->prebuffering_bytes == 0) {
644 // Start sending from the first keyframe we get. In other
645 // words, we won't send any of the backlog, but we'll start
646 // sending immediately as we get the next keyframe block.
647 // Note that this is functionally identical to the next if branch,
648 // except that we save a binary search.
649 assert(client->stream_pos == Client::STREAM_POS_AT_END);
650 assert(client->stream_pos_end == Client::STREAM_POS_NO_END);
651 client->stream_pos = stream->bytes_received;
652 client->state = Client::WAITING_FOR_KEYFRAME;
654 // We're not going to send anything to the client before we have
655 // N bytes. However, this wait might be boring; we can just as well
656 // use it to send older data if we have it. We use lower_bound()
657 // so that we are conservative and never add extra latency over just
658 // waiting (assuming CBR or nearly so); otherwise, we could want e.g.
659 // 100 kB prebuffer but end up sending a 10 MB GOP.
660 assert(client->stream_pos == Client::STREAM_POS_AT_END);
661 assert(client->stream_pos_end == Client::STREAM_POS_NO_END);
662 deque<uint64_t>::const_iterator starting_point_it =
663 lower_bound(stream->suitable_starting_points.begin(),
664 stream->suitable_starting_points.end(),
665 stream->bytes_received - stream->prebuffering_bytes);
666 if (starting_point_it == stream->suitable_starting_points.end()) {
667 // None found. Just put us at the end, and then wait for the
668 // first keyframe to appear.
669 client->stream_pos = stream->bytes_received;
670 client->state = Client::WAITING_FOR_KEYFRAME;
672 client->stream_pos = *starting_point_it;
673 client->state = Client::PREBUFFERING;
679 case Client::WAITING_FOR_KEYFRAME: {
680 Stream *stream = client->stream;
681 if (stream->suitable_starting_points.empty() ||
682 client->stream_pos > stream->suitable_starting_points.back()) {
683 // We haven't received a keyframe since this stream started waiting,
684 // so keep on waiting for one.
685 // This is postcondition #3.
686 stream->put_client_to_sleep(client);
689 client->stream_pos = stream->suitable_starting_points.back();
690 client->state = Client::PREBUFFERING;
693 case Client::PREBUFFERING: {
695 Stream *stream = client->stream;
696 size_t bytes_to_send = stream->bytes_received - client->stream_pos;
697 assert(bytes_to_send <= stream->backlog_size);
698 if (bytes_to_send < stream->prebuffering_bytes) {
699 // We don't have enough bytes buffered to start this client yet.
700 // This is postcondition #3.
701 stream->put_client_to_sleep(client);
704 client->state = Client::SENDING_DATA;
707 case Client::SENDING_DATA: {
709 skip_lost_data(client);
710 Stream *stream = client->stream;
713 size_t bytes_to_send;
714 if (client->stream_pos_end == Client::STREAM_POS_NO_END) {
715 bytes_to_send = stream->bytes_received - client->stream_pos;
717 bytes_to_send = client->stream_pos_end - client->stream_pos;
719 assert(bytes_to_send <= stream->backlog_size);
720 if (bytes_to_send == 0) {
721 if (client->stream_pos == client->stream_pos_end) { // We have a definite end, and we're at it.
722 // Add (or overwrite) a HLS zombie.
724 if (clock_gettime(CLOCK_MONOTONIC_COARSE, &now) == -1) {
725 log_perror("clock_gettime(CLOCK_MONOTONIC_COARSE)");
728 zombie.remote_addr = client->remote_addr;
729 zombie.referer = client->referer;
730 zombie.user_agent = client->user_agent;
731 zombie.url = client->stream->url + "?frag=<idle>";
732 zombie.expires = now;
733 zombie.expires.tv_sec += client->stream->hls_frag_duration * 3;
734 hls_zombies[client->get_hls_zombie_key()] = move(zombie);
736 if (more_requests(client)) {
737 // We're done sending the fragment, but should keep on reading new requests.
738 goto read_request_again;
740 // We're done sending the fragment, so now close.
741 // This is postcondition #1.
742 close_client(client);
748 // See if we need to split across the circular buffer.
749 bool more_data = false;
750 if ((client->stream_pos % stream->backlog_size) + bytes_to_send > stream->backlog_size) {
751 bytes_to_send = stream->backlog_size - (client->stream_pos % stream->backlog_size);
757 off_t offset = client->stream_pos % stream->backlog_size;
758 ret = sendfile(client->sock, stream->data_fd, &offset, bytes_to_send);
759 } while (ret == -1 && errno == EINTR);
761 if (ret == -1 && errno == EAGAIN) {
762 // We're out of socket space, so return; epoll will wake us up
763 // when there is more room.
764 // This is postcondition #4.
768 // Error, close; postcondition #1.
769 log_perror("sendfile");
770 close_client(client);
773 client->stream_pos += ret;
774 client->bytes_sent += ret;
776 assert(client->stream_pos_end == Client::STREAM_POS_NO_END || client->stream_pos <= client->stream_pos_end);
777 if (client->stream_pos == client->stream_pos_end) {
778 goto sending_data_again; // Will see that bytes_to_send == 0 and end.
779 } else if (client->stream_pos == stream->bytes_received) {
780 // We don't have any more data for this client, so put it to sleep.
781 // This is postcondition #3.
782 stream->put_client_to_sleep(client);
783 } else if (more_data && size_t(ret) == bytes_to_send) {
784 goto sending_data_again;
786 // We'll also get here for postcondition #4 (similar to the EAGAIN path above).
796 void flush_pending_data(int sock)
798 // Flush pending data, which would otherwise wait for the 200ms TCP_CORK timer
799 // to elapsed; does not cancel out TCP_CORK (since that still takes priority),
800 // but does a one-off flush.
802 if (setsockopt(sock, SOL_TCP, TCP_NODELAY, &one, sizeof(one)) == -1) {
803 log_perror("setsockopt(TCP_NODELAY)");
804 // Can still continue.
810 bool Server::send_pending_tls_data(Client *client)
812 // See if there's data from the TLS library to write.
813 if (client->tls_data_to_send == nullptr) {
814 client->tls_data_to_send = tls_get_write_buffer(client->tls_context, &client->tls_data_left_to_send);
815 if (client->tls_data_to_send == nullptr) {
816 // Really no data to send.
824 ret = write(client->sock, client->tls_data_to_send, client->tls_data_left_to_send);
825 } while (ret == -1 && errno == EINTR);
826 assert(ret < 0 || size_t(ret) <= client->tls_data_left_to_send);
828 if (ret == -1 && errno == EAGAIN) {
829 // We're out of socket space, so now we're at the “low edge” of epoll's
830 // edge triggering. epoll will tell us when there is more room, so for now,
832 // This is postcondition #4.
836 // Error! Postcondition #1.
838 close_client(client);
841 if (ret > 0 && size_t(ret) == client->tls_data_left_to_send) {
842 // All data has been sent, so we don't need to go to sleep
843 // (although we are likely to do so immediately afterwards,
844 // due to lack of client data).
845 tls_buffer_clear(client->tls_context);
846 client->tls_data_to_send = nullptr;
848 // Flush the data we just wrote, since the client probably
849 // is waiting for it.
850 flush_pending_data(client->sock);
854 // More data to send, so try again.
855 client->tls_data_to_send += ret;
856 client->tls_data_left_to_send -= ret;
857 goto send_data_again;
860 int Server::read_plain_data(Client *client, char *buf, size_t max_size)
864 ret = read(client->sock, buf, max_size);
865 } while (ret == -1 && errno == EINTR);
867 if (ret == -1 && errno == EAGAIN) {
868 // No more data right now. Nothing to do.
869 // This is postcondition #2.
874 close_client(client);
878 // OK, the socket is closed.
879 close_client(client);
886 int Server::read_tls_data(Client *client, char *buf, size_t max_size)
889 assert(!client->in_ktls_mode);
893 ret = read(client->sock, buf, max_size);
894 } while (ret == -1 && errno == EINTR);
896 if (ret == -1 && errno == EAGAIN) {
897 // No more data right now. Nothing to do.
898 // This is postcondition #2.
903 close_client(client);
907 // OK, the socket is closed.
908 close_client(client);
912 // Give it to the TLS library.
913 int err = tls_consume_stream(client->tls_context, reinterpret_cast<const unsigned char *>(buf), ret, nullptr);
915 log_tls_error("tls_consume_stream", err);
916 close_client(client);
920 // Not consumed any data. See if we can read more.
924 // Read any decrypted data available for us. (We can reuse buf, since it's free now.)
925 ret = tls_read(client->tls_context, reinterpret_cast<unsigned char *>(buf), max_size);
927 // No decrypted data for us yet, but there might be some more handshaking
928 // to send. Do that if needed, then look for more data.
929 if (send_pending_tls_data(client)) {
930 // send_pending_tls_data() hit postconditions #1 or #4.
936 log_tls_error("tls_read", ret);
937 close_client(client);
941 if (tls_established(client->tls_context)) {
942 // We're ready to enter kTLS mode, unless we still have some
943 // handshake data to send (which then must be sent as non-kTLS).
944 if (send_pending_tls_data(client)) {
945 // send_pending_tls_data() hit postconditions #1 or #4.
948 int err = tls_make_ktls(client->tls_context, client->sock); // Don't overwrite ret.
950 log_tls_error("tls_make_ktls", ret);
951 close_client(client);
954 client->in_ktls_mode = true;
961 // See if there's some data we've lost. Ideally, we should drop to a block boundary,
962 // but resync will be the mux's problem.
963 void Server::skip_lost_data(Client *client)
965 Stream *stream = client->stream;
966 if (stream == nullptr) {
969 size_t bytes_to_send = stream->bytes_received - client->stream_pos;
970 if (bytes_to_send > stream->backlog_size) {
971 size_t bytes_lost = bytes_to_send - stream->backlog_size;
972 client->bytes_lost += bytes_lost;
973 ++client->num_loss_events;
974 if (!client->close_after_response) {
975 assert(client->stream_pos_end != Client::STREAM_POS_NO_END);
977 // We've already sent a Content-Length, so we can't just skip data.
978 // Close the connection immediately and hope the other side
979 // is able to figure out that there was an error and it needs to skip.
980 client->close_after_response = true;
981 client->stream_pos = client->stream_pos_end;
983 client->stream_pos = stream->bytes_received - stream->backlog_size;
988 int Server::parse_request(Client *client)
990 vector<string> lines = split_lines(client->request);
991 client->request.clear();
993 return 400; // Bad request (empty).
996 // Parse the headers, for logging purposes.
997 HTTPHeaderMultimap headers = extract_headers(lines, client->remote_addr);
998 const auto referer_it = headers.find("Referer");
999 if (referer_it != headers.end()) {
1000 client->referer = referer_it->second;
1002 const auto user_agent_it = headers.find("User-Agent");
1003 if (user_agent_it != headers.end()) {
1004 client->user_agent = user_agent_it->second;
1006 const auto x_playback_session_id_it = headers.find("X-Playback-Session-Id");
1007 if (x_playback_session_id_it != headers.end()) {
1008 client->x_playback_session_id = x_playback_session_id_it->second;
1010 client->x_playback_session_id.clear();
1013 vector<string> request_tokens = split_tokens(lines[0]);
1014 if (request_tokens.size() < 3) {
1015 return 400; // Bad request (empty).
1017 if (request_tokens[0] != "GET") {
1018 return 400; // Should maybe be 405 instead?
1021 string url = request_tokens[1];
1023 if (url.size() > 8 && url.find("?backlog") == url.size() - 8) {
1024 client->stream_pos = Client::STREAM_POS_AT_START;
1025 url = url.substr(0, url.size() - 8);
1027 size_t pos = url.find("?frag=");
1028 if (pos != string::npos) {
1029 // Parse an endpoint of the type /stream.mp4?frag=1234-5678.
1030 const char *ptr = url.c_str() + pos + 6;
1032 // "?frag=header" is special.
1033 if (strcmp(ptr, "header") == 0) {
1034 client->stream_pos = Client::STREAM_POS_HEADER_ONLY;
1035 client->stream_pos_end = -1;
1038 long long frag_start = strtol(ptr, &endptr, 10);
1039 if (ptr == endptr || frag_start < 0 || frag_start == LLONG_MAX) {
1040 return 400; // Bad request.
1042 if (*endptr != '-') {
1043 return 400; // Bad request.
1047 long long frag_end = strtol(ptr, &endptr, 10);
1048 if (ptr == endptr || frag_end < frag_start || frag_end == LLONG_MAX) {
1049 return 400; // Bad request.
1052 if (*endptr != '\0') {
1053 return 400; // Bad request.
1056 client->stream_pos = frag_start;
1057 client->stream_pos_end = frag_end;
1059 url = url.substr(0, pos);
1061 client->stream_pos = -1;
1062 client->stream_pos_end = -1;
1066 // Figure out if we're supposed to close the socket after we've delivered the response.
1067 string protocol = request_tokens[2];
1068 if (protocol.find("HTTP/") != 0) {
1069 return 400; // Bad request.
1071 client->close_after_response = false;
1072 client->http_11 = true;
1073 if (protocol == "HTTP/1.0") {
1074 // No persistent connections.
1075 client->close_after_response = true;
1076 client->http_11 = false;
1078 const auto connection_it = headers.find("Connection");
1079 if (connection_it != headers.end() && connection_it->second == "close") {
1080 client->close_after_response = true;
1084 const auto stream_url_map_it = stream_url_map.find(url);
1085 if (stream_url_map_it != stream_url_map.end()) {
1086 // Serve a regular stream..
1087 client->stream = streams[stream_url_map_it->second].get();
1088 client->serving_hls_playlist = false;
1090 const auto stream_hls_url_map_it = stream_hls_url_map.find(url);
1091 if (stream_hls_url_map_it != stream_hls_url_map.end()) {
1092 // Serve HLS playlist.
1093 client->stream = streams[stream_hls_url_map_it->second].get();
1094 client->serving_hls_playlist = true;
1096 const auto ping_url_map_it = ping_url_map.find(url);
1097 if (ping_url_map_it == ping_url_map.end()) {
1098 return 404; // Not found.
1100 // Serve a ping (204 no error).
1106 Stream *stream = client->stream;
1108 if (client->serving_hls_playlist) {
1109 if (stream->encoding == Stream::STREAM_ENCODING_METACUBE) {
1110 // This doesn't make any sense, and is hard to implement, too.
1117 if (client->stream_pos_end == Client::STREAM_POS_NO_END) {
1118 if (stream->unavailable) {
1119 return 503; // Service unavailable.
1122 // This stream won't end, so we don't have a content-length,
1123 // and can just as well tell the client it's Connection: close
1124 // (otherwise, we'd have to implement chunking TE for no good reason).
1125 client->close_after_response = true;
1127 if (stream->encoding == Stream::STREAM_ENCODING_METACUBE) {
1128 // This doesn't make any sense, and is hard to implement, too.
1129 return 416; // Range not satisfiable.
1132 // Check that we have the requested fragment in our backlog.
1133 size_t buffer_end = stream->bytes_received;
1134 size_t buffer_start = (buffer_end <= stream->backlog_size) ? 0 : buffer_end - stream->backlog_size;
1136 if (client->stream_pos_end > buffer_end ||
1137 client->stream_pos < buffer_start) {
1138 return 416; // Range not satisfiable.
1142 client->stream = stream;
1143 if (setsockopt(client->sock, SOL_SOCKET, SO_MAX_PACING_RATE, &client->stream->pacing_rate, sizeof(client->stream->pacing_rate)) == -1) {
1144 if (client->stream->pacing_rate != ~0U) {
1145 log_perror("setsockopt(SO_MAX_PACING_RATE)");
1148 client->request.clear();
1153 void Server::construct_stream_header(Client *client)
1155 Stream *stream = client->stream;
1156 string response = stream->http_header;
1157 if (client->stream_pos == Client::STREAM_POS_HEADER_ONLY) {
1159 snprintf(buf, sizeof(buf), "Content-Length: %zu\r\n", stream->stream_header.size());
1160 response.append(buf);
1161 } else if (client->stream_pos_end != Client::STREAM_POS_NO_END) {
1163 snprintf(buf, sizeof(buf), "Content-Length: %" PRIu64 "\r\n", client->stream_pos_end - client->stream_pos);
1164 response.append(buf);
1166 if (client->http_11) {
1167 assert(response.find("HTTP/1.0") == 0);
1168 response[7] = '1'; // Change to HTTP/1.1.
1169 if (client->close_after_response) {
1170 response.append("Connection: close\r\n");
1173 assert(client->close_after_response);
1175 if (!stream->allow_origin.empty()) {
1176 response.append("Access-Control-Allow-Origin: ");
1177 response.append(stream->allow_origin);
1178 response.append("\r\n");
1180 if (stream->encoding == Stream::STREAM_ENCODING_RAW) {
1181 response.append("\r\n");
1182 } else if (stream->encoding == Stream::STREAM_ENCODING_METACUBE) {
1183 response.append("Content-Encoding: metacube\r\n\r\n");
1184 if (!stream->stream_header.empty()) {
1185 metacube2_block_header hdr;
1186 memcpy(hdr.sync, METACUBE2_SYNC, sizeof(hdr.sync));
1187 hdr.size = htonl(stream->stream_header.size());
1188 hdr.flags = htons(METACUBE_FLAGS_HEADER);
1189 hdr.csum = htons(metacube2_compute_crc(&hdr));
1190 response.append(string(reinterpret_cast<char *>(&hdr), sizeof(hdr)));
1195 if (client->stream_pos == Client::STREAM_POS_HEADER_ONLY) {
1196 client->state = Client::SENDING_SHORT_RESPONSE;
1197 response.append(stream->stream_header);
1199 client->state = Client::SENDING_HEADER;
1200 if (client->stream_pos_end == Client::STREAM_POS_NO_END) { // Fragments don't contain stream headers.
1201 response.append(stream->stream_header);
1205 client->header_or_short_response_holder = move(response);
1206 client->header_or_short_response = &client->header_or_short_response_holder;
1209 change_epoll_events(client, EPOLLOUT | EPOLLET | EPOLLRDHUP);
1212 void Server::construct_error(Client *client, int error_code)
1215 if (client->http_11 && client->close_after_response) {
1216 snprintf(error, sizeof(error),
1217 "HTTP/1.1 %d Error\r\nContent-Type: text/plain\r\nConnection: close\r\n\r\nSomething went wrong. Sorry.\r\n",
1220 snprintf(error, sizeof(error),
1221 "HTTP/1.%d %d Error\r\nContent-Type: text/plain\r\nContent-Length: 30\r\n\r\nSomething went wrong. Sorry.\r\n",
1222 client->http_11, error_code);
1224 client->header_or_short_response_holder = error;
1225 client->header_or_short_response = &client->header_or_short_response_holder;
1228 client->state = Client::SENDING_SHORT_RESPONSE;
1229 change_epoll_events(client, EPOLLOUT | EPOLLET | EPOLLRDHUP);
1232 void Server::construct_hls_playlist(Client *client)
1234 Stream *stream = client->stream;
1235 shared_ptr<const string> *cache;
1236 if (client->http_11) {
1237 if (client->close_after_response) {
1238 cache = &stream->hls_playlist_http11_close;
1240 cache = &stream->hls_playlist_http11_persistent;
1243 assert(client->close_after_response);
1244 cache = &stream->hls_playlist_http10;
1247 if (*cache == nullptr) {
1248 *cache = stream->generate_hls_playlist(client->http_11, client->close_after_response);
1250 client->header_or_short_response_ref = *cache;
1251 client->header_or_short_response = cache->get();
1254 client->state = Client::SENDING_SHORT_RESPONSE;
1255 change_epoll_events(client, EPOLLOUT | EPOLLET | EPOLLRDHUP);
1258 void Server::construct_204(Client *client)
1260 const auto ping_url_map_it = ping_url_map.find(client->url);
1261 assert(ping_url_map_it != ping_url_map.end());
1264 if (client->http_11) {
1265 response = "HTTP/1.1 204 No Content\r\n";
1266 if (client->close_after_response) {
1267 response.append("Connection: close\r\n");
1270 response = "HTTP/1.0 204 No Content\r\n";
1271 assert(client->close_after_response);
1273 if (!ping_url_map_it->second.empty()) {
1274 response.append("Access-Control-Allow-Origin: ");
1275 response.append(ping_url_map_it->second);
1276 response.append("\r\n");
1278 response.append("\r\n");
1280 client->header_or_short_response_holder = move(response);
1281 client->header_or_short_response = &client->header_or_short_response_holder;
1284 client->state = Client::SENDING_SHORT_RESPONSE;
1285 change_epoll_events(client, EPOLLOUT | EPOLLET | EPOLLRDHUP);
1291 void delete_from(vector<T> *v, T elem)
1293 typename vector<T>::iterator new_end = remove(v->begin(), v->end(), elem);
1294 v->erase(new_end, v->end());
1297 void send_ktls_close(int sock)
1299 uint8_t record_type = 21; // Alert.
1301 1, // Warning level (but still fatal!).
1305 int cmsg_len = sizeof(record_type);
1306 char buf[CMSG_SPACE(cmsg_len)];
1309 msg.msg_control = buf;
1310 msg.msg_controllen = sizeof(buf);
1311 cmsghdr *cmsg = CMSG_FIRSTHDR(&msg);
1312 cmsg->cmsg_level = SOL_TLS;
1313 cmsg->cmsg_type = TLS_SET_RECORD_TYPE;
1314 cmsg->cmsg_len = CMSG_LEN(cmsg_len);
1315 *CMSG_DATA(cmsg) = record_type;
1316 msg.msg_controllen = cmsg->cmsg_len;
1319 msg_iov.iov_base = body;
1320 msg_iov.iov_len = sizeof(body);
1321 msg.msg_iov = &msg_iov;
1326 err = sendmsg(sock, &msg, 0);
1327 } while (err == -1 && errno == EINTR); // Ignore all other errors.
1332 void Server::close_client(Client *client)
1334 if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, client->sock, nullptr) == -1) {
1335 log_perror("epoll_ctl(EPOLL_CTL_DEL)");
1339 // This client could be sleeping, so we'll need to fix that. (Argh, O(n).)
1340 if (client->stream != nullptr) {
1341 delete_from(&client->stream->sleeping_clients, client);
1342 delete_from(&client->stream->to_process, client);
1345 if (client->tls_context) {
1346 if (client->in_ktls_mode) {
1347 // Keep GnuTLS happy.
1348 send_ktls_close(client->sock);
1350 tls_destroy_context(client->tls_context);
1353 // Log to access_log.
1354 access_log->write(client->get_stats());
1357 safe_close(client->sock);
1359 clients.erase(client->sock);
1362 void Server::change_epoll_events(Client *client, uint32_t events)
1366 ev.data.ptr = client;
1368 if (epoll_ctl(epoll_fd, EPOLL_CTL_MOD, client->sock, &ev) == -1) {
1369 log_perror("epoll_ctl(EPOLL_CTL_MOD)");
1374 bool Server::more_requests(Client *client)
1376 if (client->close_after_response) {
1380 // Log to access_log.
1381 access_log->write(client->get_stats());
1383 flush_pending_data(client->sock);
1385 // Switch states and reset the parsers. We don't reset statistics.
1386 client->state = Client::READING_REQUEST;
1387 client->url.clear();
1388 client->stream = NULL;
1389 client->header_or_short_response = nullptr;
1390 client->header_or_short_response_holder.clear();
1391 client->header_or_short_response_ref.reset();
1392 client->header_or_short_response_bytes_sent = 0;
1393 client->bytes_sent = 0;
1394 start_client_timeout_timer(client);
1396 change_epoll_events(client, EPOLLIN | EPOLLET | EPOLLRDHUP); // No TLS handshake, so no EPOLLOUT needed.
1401 void Server::process_queued_data()
1404 lock_guard<mutex> lock(queued_clients_mutex);
1406 for (const pair<int, Acceptor *> &id_and_acceptor : queued_add_clients) {
1407 add_client(id_and_acceptor.first, id_and_acceptor.second);
1409 queued_add_clients.clear();
1412 for (unique_ptr<Stream> &stream : streams) {
1413 stream->process_queued_data();