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1 //
2 // Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
3 //
4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6 //
7 // Official repository: https://github.com/boostorg/beast
8 //
9 
10 #ifndef BOOST_BEAST_WEBSOCKET_IMPL_STREAM_IMPL_HPP
11 #define BOOST_BEAST_WEBSOCKET_IMPL_STREAM_IMPL_HPP
12 
13 #include <boost/beast/websocket/rfc6455.hpp>
14 #include <boost/beast/websocket/detail/frame.hpp>
15 #include <boost/beast/websocket/detail/hybi13.hpp>
16 #include <boost/beast/websocket/detail/mask.hpp>
17 #include <boost/beast/websocket/detail/pmd_extension.hpp>
18 #include <boost/beast/websocket/detail/prng.hpp>
19 #include <boost/beast/websocket/detail/service.hpp>
20 #include <boost/beast/websocket/detail/soft_mutex.hpp>
21 #include <boost/beast/websocket/detail/utf8_checker.hpp>
22 #include <boost/beast/http/read.hpp>
23 #include <boost/beast/http/write.hpp>
24 #include <boost/beast/http/rfc7230.hpp>
25 #include <boost/beast/core/buffers_cat.hpp>
26 #include <boost/beast/core/buffers_prefix.hpp>
27 #include <boost/beast/core/buffers_suffix.hpp>
28 #include <boost/beast/core/flat_static_buffer.hpp>
29 #include <boost/beast/core/saved_handler.hpp>
30 #include <boost/beast/core/static_buffer.hpp>
31 #include <boost/beast/core/stream_traits.hpp>
32 #include <boost/beast/core/detail/clamp.hpp>
33 #include <boost/asio/steady_timer.hpp>
34 #include <boost/core/empty_value.hpp>
35 #include <boost/enable_shared_from_this.hpp>
36 #include <boost/shared_ptr.hpp>
37 #include <boost/optional.hpp>
38 
39 namespace boost {
40 namespace beast {
41 namespace websocket {
42 
43 template<
44     class NextLayer, bool deflateSupported>
45 struct stream<NextLayer, deflateSupported>::impl_type
46     : boost::empty_value<NextLayer>
47     , detail::service::impl_type
48     , detail::impl_base<deflateSupported>
49 {
streamboost::beast::websocket::stream::impl_type50     NextLayer& stream() noexcept
51     {
52         return this->boost::empty_value<
53             NextLayer>::get();
54     }
55 
56     boost::weak_ptr<impl_type>
weak_from_thisboost::beast::websocket::stream::impl_type57     weak_from_this()
58     {
59         return boost::static_pointer_cast<
60             impl_type>(this->detail::service::
61                 impl_type::shared_from_this());
62     }
63 
64     boost::shared_ptr<impl_type>
shared_thisboost::beast::websocket::stream::impl_type65     shared_this()
66     {
67         return boost::static_pointer_cast<
68             impl_type>(this->detail::service::
69                 impl_type::shared_from_this());
70     }
71 
72     net::steady_timer       timer;          // used for timeouts
73     close_reason            cr;             // set from received close frame
74     control_cb_type         ctrl_cb;        // control callback
75 
76     std::size_t             rd_msg_max      /* max message size */ = 16 * 1024 * 1024;
77     std::uint64_t           rd_size         /* total size of current message so far */ = 0;
78     std::uint64_t           rd_remain       /* message frame bytes left in current frame */ = 0;
79     detail::frame_header    rd_fh;          // current frame header
80     detail::prepared_key    rd_key;         // current stateful mask key
81     detail::frame_buffer    rd_fb;          // to write control frames (during reads)
82     detail::utf8_checker    rd_utf8;        // to validate utf8
83     static_buffer<
84         +tcp_frame_size>    rd_buf;         // buffer for reads
85     detail::opcode          rd_op           /* current message binary or text */ = detail::opcode::text;
86     bool                    rd_cont         /* `true` if the next frame is a continuation */ = false;
87     bool                    rd_done         /* set when a message is done */ = true;
88     bool                    rd_close        /* did we read a close frame? */ = false;
89     detail::soft_mutex      rd_block;       // op currently reading
90 
91     role_type               role            /* server or client */ = role_type::client;
92     status                  status_         /* state of the object */ = status::closed;
93 
94     detail::soft_mutex      wr_block;       // op currently writing
95     bool                    wr_close        /* did we write a close frame? */ = false;
96     bool                    wr_cont         /* next write is a continuation */ = false;
97     bool                    wr_frag         /* autofrag the current message */ = false;
98     bool                    wr_frag_opt     /* autofrag option setting */ = true;
99     bool                    wr_compress;    /* compress current message */
100     bool                    wr_compress_opt /* compress message setting */ = true;
101     detail::opcode          wr_opcode       /* message type */ = detail::opcode::text;
102     std::unique_ptr<
103         std::uint8_t[]>     wr_buf;         // write buffer
104     std::size_t             wr_buf_size     /* write buffer size (current message) */ = 0;
105     std::size_t             wr_buf_opt      /* write buffer size option setting */ = 4096;
106     detail::fh_buffer       wr_fb;          // header buffer used for writes
107 
108     saved_handler           op_rd;          // paused read op
109     saved_handler           op_wr;          // paused write op
110     saved_handler           op_ping;        // paused ping op
111     saved_handler           op_idle_ping;   // paused idle ping op
112     saved_handler           op_close;       // paused close op
113     saved_handler           op_r_rd;        // paused read op (async read)
114     saved_handler           op_r_close;     // paused close op (async read)
115 
116     bool    idle_pinging = false;
117     bool    secure_prng_ = true;
118     bool    ec_delivered = false;
119     bool    timed_out = false;
120     int     idle_counter = 0;
121 
122     detail::decorator       decorator_opt;  // Decorator for HTTP messages
123     timeout                 timeout_opt;    // Timeout/idle settings
124 
125     template<class... Args>
impl_typeboost::beast::websocket::stream::impl_type126     impl_type(Args&&... args)
127         : boost::empty_value<NextLayer>(
128             boost::empty_init_t{},
129             std::forward<Args>(args)...)
130         , detail::service::impl_type(
131             this->get_context(
132                 this->boost::empty_value<NextLayer>::get().get_executor()))
133         , timer(this->boost::empty_value<NextLayer>::get().get_executor())
134     {
135         timeout_opt.handshake_timeout = none();
136         timeout_opt.idle_timeout = none();
137         timeout_opt.keep_alive_pings = false;
138     }
139 
140     void
shutdownboost::beast::websocket::stream::impl_type141     shutdown() override
142     {
143         op_rd.reset();
144         op_wr.reset();
145         op_ping.reset();
146         op_idle_ping.reset();
147         op_close.reset();
148         op_r_rd.reset();
149         op_r_close.reset();
150     }
151 
152     void
openboost::beast::websocket::stream::impl_type153     open(role_type role_)
154     {
155         // VFALCO TODO analyze and remove dupe code in reset()
156         timer.expires_at(never());
157         timed_out = false;
158         cr.code = close_code::none;
159         role = role_;
160         status_ = status::open;
161         rd_remain = 0;
162         rd_cont = false;
163         rd_done = true;
164         // Can't clear this because accept uses it
165         //rd_buf.reset();
166         rd_fh.fin = false;
167         rd_close = false;
168         wr_close = false;
169         // These should not be necessary, because all completion
170         // handlers must be allowed to execute otherwise the
171         // stream exhibits undefined behavior.
172         wr_block.reset();
173         rd_block.reset();
174 
175         wr_cont = false;
176         wr_buf_size = 0;
177 
178         this->open_pmd(role);
179     }
180 
181     void
closeboost::beast::websocket::stream::impl_type182     close()
183     {
184         timer.cancel();
185         wr_buf.reset();
186         this->close_pmd();
187     }
188 
189     void
resetboost::beast::websocket::stream::impl_type190     reset()
191     {
192         BOOST_ASSERT(status_ != status::open);
193         timer.expires_at(never());
194         cr.code = close_code::none;
195         rd_remain = 0;
196         rd_cont = false;
197         rd_done = true;
198         rd_buf.consume(rd_buf.size());
199         rd_fh.fin = false;
200         rd_close = false;
201         wr_close = false;
202         wr_cont = false;
203         // These should not be necessary, because all completion
204         // handlers must be allowed to execute otherwise the
205         // stream exhibits undefined behavior.
206         wr_block.reset();
207         rd_block.reset();
208 
209         // VFALCO Is this needed?
210         timer.cancel();
211     }
212 
213     void
time_outboost::beast::websocket::stream::impl_type214     time_out()
215     {
216         timed_out = true;
217         change_status(status::closed);
218         close_socket(get_lowest_layer(stream()));
219     }
220 
221     // Called just before sending
222     // the first frame of each message
223     void
begin_msgboost::beast::websocket::stream::impl_type224     begin_msg()
225     {
226         wr_frag = wr_frag_opt;
227         wr_compress =
228             this->pmd_enabled() && wr_compress_opt;
229 
230         // Maintain the write buffer
231         if( this->pmd_enabled() ||
232             role == role_type::client)
233         {
234             if(! wr_buf ||
235                 wr_buf_size != wr_buf_opt)
236             {
237                 wr_buf_size = wr_buf_opt;
238                 wr_buf = boost::make_unique_noinit<
239                     std::uint8_t[]>(wr_buf_size);
240             }
241         }
242         else
243         {
244             wr_buf_size = wr_buf_opt;
245             wr_buf.reset();
246         }
247 
248         //
249     }
250 
251     //--------------------------------------------------------------------------
252 
253     template<class Decorator>
254     request_type
255     build_request(
256         detail::sec_ws_key_type& key,
257         string_view host, string_view target,
258         Decorator const& decorator);
259 
260     void
261     on_response(
262         response_type const& res,
263         detail::sec_ws_key_type const& key,
264         error_code& ec);
265 
266     template<class Body, class Allocator, class Decorator>
267     response_type
268     build_response(
269         http::request<Body,
270             http::basic_fields<Allocator>> const& req,
271         Decorator const& decorator,
272         error_code& result);
273 
274     // Attempt to read a complete frame header.
275     // Returns `false` if more bytes are needed
276     template<class DynamicBuffer>
277     bool
278     parse_fh(detail::frame_header& fh,
279         DynamicBuffer& b, error_code& ec);
280 
281     std::uint32_t
create_maskboost::beast::websocket::stream::impl_type282     create_mask()
283     {
284         auto g = detail::make_prng(secure_prng_);
285         for(;;)
286             if(auto key = g())
287                 return key;
288     }
289 
290     template<class DynamicBuffer>
291     std::size_t
read_size_hint_dbboost::beast::websocket::stream::impl_type292     read_size_hint_db(DynamicBuffer& buffer) const
293     {
294         auto const initial_size = (std::min)(
295             +tcp_frame_size,
296             buffer.max_size() - buffer.size());
297         if(initial_size == 0)
298             return 1; // buffer is full
299         return this->read_size_hint_pmd(
300             initial_size, rd_done, rd_remain, rd_fh);
301     }
302 
303     template<class DynamicBuffer>
304     void
305     write_ping(DynamicBuffer& db,
306         detail::opcode code, ping_data const& data);
307 
308     template<class DynamicBuffer>
309     void
310     write_close(DynamicBuffer& db, close_reason const& cr);
311 
312     //--------------------------------------------------------------------------
313 
314     void
set_optionboost::beast::websocket::stream::impl_type315     set_option(timeout const& opt)
316     {
317         if( opt.handshake_timeout == none() &&
318             opt.idle_timeout == none())
319         {
320             // turn timer off
321             timer.cancel();
322             timer.expires_at(never());
323         }
324 
325         timeout_opt = opt;
326     }
327 
328     // Determine if an operation should stop and
329     // deliver an error code to the completion handler.
330     //
331     // This function must be called at the beginning
332     // of every composed operation, and every time a
333     // composed operation receives an intermediate
334     // completion.
335     //
336     bool
check_stop_nowboost::beast::websocket::stream::impl_type337     check_stop_now(error_code& ec)
338     {
339         // Deliver the timeout to the first caller
340         if(timed_out)
341         {
342             timed_out = false;
343             ec = beast::error::timeout;
344             return true;
345         }
346 
347         // If the stream is closed then abort
348         if( status_ == status::closed ||
349             status_ == status::failed)
350         {
351             //BOOST_ASSERT(ec_delivered);
352             ec = net::error::operation_aborted;
353             return true;
354         }
355 
356         // If no error then keep going
357         if(! ec)
358             return false;
359 
360         // Is this the first error seen?
361         if(ec_delivered)
362         {
363             // No, so abort
364             ec = net::error::operation_aborted;
365             return true;
366         }
367 
368         // Deliver the error to the completion handler
369         ec_delivered = true;
370         if(status_ != status::closed)
371             status_ = status::failed;
372         return true;
373     }
374 
375     // Change the status of the stream
376     void
change_statusboost::beast::websocket::stream::impl_type377     change_status(status new_status)
378     {
379         switch(new_status)
380         {
381         case status::handshake:
382             break;
383 
384         case status::open:
385             break;
386 
387         case status::closing:
388             //BOOST_ASSERT(status_ == status::open);
389             break;
390 
391         case status::failed:
392         case status::closed:
393             // this->close(); // Is this right?
394             break;
395 
396         default:
397             break;
398         }
399         status_ = new_status;
400     }
401 
402     // Called to disarm the idle timeout counter
403     void
reset_idleboost::beast::websocket::stream::impl_type404     reset_idle()
405     {
406         idle_counter = 0;
407     }
408 
409     // Maintain the expiration timer
410     template<class Executor>
411     void
update_timerboost::beast::websocket::stream::impl_type412     update_timer(Executor const& ex)
413     {
414         switch(status_)
415         {
416         case status::handshake:
417             BOOST_ASSERT(idle_counter == 0);
418             if(! is_timer_set() &&
419                 timeout_opt.handshake_timeout != none())
420             {
421                 timer.expires_after(
422                     timeout_opt.handshake_timeout);
423 
424                 BOOST_ASIO_HANDLER_LOCATION((
425                     __FILE__, __LINE__,
426                     "websocket::check_stop_now"
427                     ));
428 
429                 timer.async_wait(
430                     timeout_handler<Executor>(
431                         ex, this->weak_from_this()));
432             }
433             break;
434 
435         case status::open:
436             if(timeout_opt.idle_timeout != none())
437             {
438                 idle_counter = 0;
439                 if(timeout_opt.keep_alive_pings)
440                     timer.expires_after(
441                         timeout_opt.idle_timeout / 2);
442                 else
443                     timer.expires_after(
444                         timeout_opt.idle_timeout);
445 
446                 BOOST_ASIO_HANDLER_LOCATION((
447                     __FILE__, __LINE__,
448                     "websocket::check_stop_now"
449                     ));
450 
451                 timer.async_wait(
452                     timeout_handler<Executor>(
453                         ex, this->weak_from_this()));
454             }
455             else
456             {
457                 timer.cancel();
458                 timer.expires_at(never());
459             }
460             break;
461 
462         case status::closing:
463             if(timeout_opt.handshake_timeout != none())
464             {
465                 idle_counter = 0;
466                 timer.expires_after(
467                     timeout_opt.handshake_timeout);
468 
469                 BOOST_ASIO_HANDLER_LOCATION((
470                     __FILE__, __LINE__,
471                     "websocket::check_stop_now"
472                     ));
473 
474                 timer.async_wait(
475                     timeout_handler<Executor>(
476                         ex, this->weak_from_this()));
477             }
478             else
479             {
480                 // VFALCO This assert goes off when there's also
481                 // a pending read with the timer set. The bigger
482                 // fix is to give close its own timeout, instead
483                 // of using the handshake timeout.
484                 // BOOST_ASSERT(! is_timer_set());
485             }
486             break;
487 
488         case status::failed:
489         case status::closed:
490             // this->close(); // Is this right?
491             timer.cancel();
492             timer.expires_at(never());
493             break;
494         }
495     }
496 
497 private:
498     template<class Executor>
499     static net::execution_context&
get_contextboost::beast::websocket::stream::impl_type500     get_context(Executor const& ex,
501         typename std::enable_if< net::execution::is_executor<Executor>::value >::type* = 0)
502     {
503         return net::query(ex, net::execution::context);
504     }
505 
506     template<class Executor>
507     static net::execution_context&
get_contextboost::beast::websocket::stream::impl_type508     get_context(Executor const& ex,
509         typename std::enable_if< !net::execution::is_executor<Executor>::value >::type* = 0)
510     {
511         return ex.context();
512     }
513 
514     bool
is_timer_setboost::beast::websocket::stream::impl_type515     is_timer_set() const
516     {
517         return timer.expiry() != never();
518     }
519 
520     template<class Executor>
521     class timeout_handler
522         : boost::empty_value<Executor>
523     {
524         boost::weak_ptr<impl_type> wp_;
525 
526     public:
timeout_handler(Executor const & ex,boost::weak_ptr<impl_type> && wp)527         timeout_handler(
528             Executor const& ex,
529             boost::weak_ptr<impl_type>&& wp)
530             : boost::empty_value<Executor>(
531                 boost::empty_init_t{}, ex)
532             , wp_(std::move(wp))
533         {
534         }
535 
536         using executor_type = Executor;
537 
538         executor_type
get_executor() const539         get_executor() const noexcept
540         {
541             return this->get();
542         }
543 
544         void
operator ()(error_code ec)545         operator()(error_code ec)
546         {
547             // timer canceled?
548             if(ec == net::error::operation_aborted)
549                 return;
550             BOOST_ASSERT(! ec);
551 
552             // stream destroyed?
553             auto sp = wp_.lock();
554             if(! sp)
555                 return;
556             auto& impl = *sp;
557 
558             switch(impl.status_)
559             {
560             case status::handshake:
561                 impl.time_out();
562                 return;
563 
564             case status::open:
565                 // timeout was disabled
566                 if(impl.timeout_opt.idle_timeout == none())
567                     return;
568 
569                 if( impl.timeout_opt.keep_alive_pings &&
570                     impl.idle_counter < 1)
571                 {
572                     {
573                         BOOST_ASIO_HANDLER_LOCATION((
574                             __FILE__, __LINE__,
575                             "websocket::timeout_handler"
576                             ));
577 
578                         idle_ping_op<Executor>(sp, get_executor());
579                     }
580                     ++impl.idle_counter;
581                     impl.timer.expires_after(
582                         impl.timeout_opt.idle_timeout / 2);
583 
584                     {
585                         BOOST_ASIO_HANDLER_LOCATION((
586                             __FILE__, __LINE__,
587                             "websocket::timeout_handler"
588                             ));
589 
590                         impl.timer.async_wait(std::move(*this));
591                     }
592                     return;
593                 }
594 
595                 impl.time_out();
596                 return;
597 
598             case status::closing:
599                 impl.time_out();
600                 return;
601 
602             case status::closed:
603             case status::failed:
604                 // nothing to do?
605                 return;
606             }
607         }
608     };
609 };
610 
611 //--------------------------------------------------------------------------
612 //
613 // client
614 //
615 //--------------------------------------------------------------------------
616 
617 template<class NextLayer, bool deflateSupported>
618 template<class Decorator>
619 request_type
620 stream<NextLayer, deflateSupported>::impl_type::
build_request(detail::sec_ws_key_type & key,string_view host,string_view target,Decorator const & decorator)621 build_request(
622     detail::sec_ws_key_type& key,
623     string_view host, string_view target,
624     Decorator const& decorator)
625 {
626     request_type req;
627     req.target(target);
628     req.version(11);
629     req.method(http::verb::get);
630     req.set(http::field::host, host);
631     req.set(http::field::upgrade, "websocket");
632     req.set(http::field::connection, "upgrade");
633     detail::make_sec_ws_key(key);
634     req.set(http::field::sec_websocket_key, key);
635     req.set(http::field::sec_websocket_version, "13");
636     this->build_request_pmd(req);
637     decorator_opt(req);
638     decorator(req);
639     return req;
640 }
641 
642 // Called when the WebSocket Upgrade response is received
643 template<class NextLayer, bool deflateSupported>
644 void
645 stream<NextLayer, deflateSupported>::impl_type::
on_response(response_type const & res,detail::sec_ws_key_type const & key,error_code & ec)646 on_response(
647     response_type const& res,
648     detail::sec_ws_key_type const& key,
649     error_code& ec)
650 {
651     auto const err =
652         [&](error e)
653         {
654             ec = e;
655         };
656     if(res.result() != http::status::switching_protocols)
657         return err(error::upgrade_declined);
658     if(res.version() != 11)
659         return err(error::bad_http_version);
660     {
661         auto const it = res.find(http::field::connection);
662         if(it == res.end())
663             return err(error::no_connection);
664         if(! http::token_list{it->value()}.exists("upgrade"))
665             return err(error::no_connection_upgrade);
666     }
667     {
668         auto const it = res.find(http::field::upgrade);
669         if(it == res.end())
670             return err(error::no_upgrade);
671         if(! http::token_list{it->value()}.exists("websocket"))
672             return err(error::no_upgrade_websocket);
673     }
674     {
675         auto const it = res.find(
676             http::field::sec_websocket_accept);
677         if(it == res.end())
678             return err(error::no_sec_accept);
679         detail::sec_ws_accept_type acc;
680         detail::make_sec_ws_accept(acc, key);
681         if(acc.compare(it->value()) != 0)
682             return err(error::bad_sec_accept);
683     }
684 
685     ec = {};
686     this->on_response_pmd(res);
687     this->open(role_type::client);
688 }
689 
690 //------------------------------------------------------------------------------
691 
692 // Attempt to read a complete frame header.
693 // Returns `false` if more bytes are needed
694 template<class NextLayer, bool deflateSupported>
695 template<class DynamicBuffer>
696 bool
697 stream<NextLayer, deflateSupported>::impl_type::
parse_fh(detail::frame_header & fh,DynamicBuffer & b,error_code & ec)698 parse_fh(
699     detail::frame_header& fh,
700     DynamicBuffer& b,
701     error_code& ec)
702 {
703     if(buffer_bytes(b.data()) < 2)
704     {
705         // need more bytes
706         ec = {};
707         return false;
708     }
709     buffers_suffix<typename
710         DynamicBuffer::const_buffers_type> cb{
711             b.data()};
712     std::size_t need;
713     {
714         std::uint8_t tmp[2];
715         cb.consume(net::buffer_copy(
716             net::buffer(tmp), cb));
717         fh.len = tmp[1] & 0x7f;
718         switch(fh.len)
719         {
720             case 126: need = 2; break;
721             case 127: need = 8; break;
722             default:
723                 need = 0;
724         }
725         fh.mask = (tmp[1] & 0x80) != 0;
726         if(fh.mask)
727             need += 4;
728         if(buffer_bytes(cb) < need)
729         {
730             // need more bytes
731             ec = {};
732             return false;
733         }
734         fh.op   = static_cast<
735             detail::opcode>(tmp[0] & 0x0f);
736         fh.fin  = (tmp[0] & 0x80) != 0;
737         fh.rsv1 = (tmp[0] & 0x40) != 0;
738         fh.rsv2 = (tmp[0] & 0x20) != 0;
739         fh.rsv3 = (tmp[0] & 0x10) != 0;
740     }
741     switch(fh.op)
742     {
743     case detail::opcode::binary:
744     case detail::opcode::text:
745         if(rd_cont)
746         {
747             // new data frame when continuation expected
748             ec = error::bad_data_frame;
749             return false;
750         }
751         if(fh.rsv2 || fh.rsv3 ||
752             ! this->rd_deflated(fh.rsv1))
753         {
754             // reserved bits not cleared
755             ec = error::bad_reserved_bits;
756             return false;
757         }
758         break;
759 
760     case detail::opcode::cont:
761         if(! rd_cont)
762         {
763             // continuation without an active message
764             ec = error::bad_continuation;
765             return false;
766         }
767         if(fh.rsv1 || fh.rsv2 || fh.rsv3)
768         {
769             // reserved bits not cleared
770             ec = error::bad_reserved_bits;
771             return false;
772         }
773         break;
774 
775     default:
776         if(detail::is_reserved(fh.op))
777         {
778             // reserved opcode
779             ec = error::bad_opcode;
780             return false;
781         }
782         if(! fh.fin)
783         {
784             // fragmented control message
785             ec = error::bad_control_fragment;
786             return false;
787         }
788         if(fh.len > 125)
789         {
790             // invalid length for control message
791             ec = error::bad_control_size;
792             return false;
793         }
794         if(fh.rsv1 || fh.rsv2 || fh.rsv3)
795         {
796             // reserved bits not cleared
797             ec = error::bad_reserved_bits;
798             return false;
799         }
800         break;
801     }
802     if(role == role_type::server && ! fh.mask)
803     {
804         // unmasked frame from client
805         ec = error::bad_unmasked_frame;
806         return false;
807     }
808     if(role == role_type::client && fh.mask)
809     {
810         // masked frame from server
811         ec = error::bad_masked_frame;
812         return false;
813     }
814     if(detail::is_control(fh.op) &&
815         buffer_bytes(cb) < need + fh.len)
816     {
817         // Make the entire control frame payload
818         // get read in before we return `true`
819         return false;
820     }
821     switch(fh.len)
822     {
823     case 126:
824     {
825 
826         std::uint16_t len_be;
827         BOOST_ASSERT(buffer_bytes(cb) >= sizeof(len_be));
828         cb.consume(net::buffer_copy(
829             net::mutable_buffer(&len_be, sizeof(len_be)), cb));
830         fh.len = endian::big_to_native(len_be);
831         if(fh.len < 126)
832         {
833             // length not canonical
834             ec = error::bad_size;
835             return false;
836         }
837         break;
838     }
839     case 127:
840     {
841         std::uint64_t len_be;
842         BOOST_ASSERT(buffer_bytes(cb) >= sizeof(len_be));
843         cb.consume(net::buffer_copy(
844             net::mutable_buffer(&len_be, sizeof(len_be)), cb));
845         fh.len = endian::big_to_native(len_be);
846         if(fh.len < 65536)
847         {
848             // length not canonical
849             ec = error::bad_size;
850             return false;
851         }
852         break;
853     }
854     }
855     if(fh.mask)
856     {
857         std::uint32_t key_le;
858         BOOST_ASSERT(buffer_bytes(cb) >= sizeof(key_le));
859         cb.consume(net::buffer_copy(
860             net::mutable_buffer(&key_le, sizeof(key_le)), cb));
861         fh.key = endian::little_to_native(key_le);
862         detail::prepare_key(rd_key, fh.key);
863     }
864     else
865     {
866         // initialize this otherwise operator== breaks
867         fh.key = 0;
868     }
869     if(! detail::is_control(fh.op))
870     {
871         if(fh.op != detail::opcode::cont)
872         {
873             rd_size = 0;
874             rd_op = fh.op;
875         }
876         else
877         {
878             if(rd_size > (std::numeric_limits<
879                 std::uint64_t>::max)() - fh.len)
880             {
881                 // message size exceeds configured limit
882                 ec = error::message_too_big;
883                 return false;
884             }
885         }
886         if(! this->rd_deflated())
887         {
888             if(rd_msg_max && beast::detail::sum_exceeds(
889                 rd_size, fh.len, rd_msg_max))
890             {
891                 // message size exceeds configured limit
892                 ec = error::message_too_big;
893                 return false;
894             }
895         }
896         rd_cont = ! fh.fin;
897         rd_remain = fh.len;
898     }
899     b.consume(b.size() - buffer_bytes(cb));
900     ec = {};
901     return true;
902 }
903 
904 template<class NextLayer, bool deflateSupported>
905 template<class DynamicBuffer>
906 void
907 stream<NextLayer, deflateSupported>::impl_type::
write_ping(DynamicBuffer & db,detail::opcode code,ping_data const & data)908 write_ping(DynamicBuffer& db,
909     detail::opcode code, ping_data const& data)
910 {
911     detail::frame_header fh;
912     fh.op = code;
913     fh.fin = true;
914     fh.rsv1 = false;
915     fh.rsv2 = false;
916     fh.rsv3 = false;
917     fh.len = data.size();
918     fh.mask = role == role_type::client;
919     if(fh.mask)
920         fh.key = create_mask();
921     detail::write(db, fh);
922     if(data.empty())
923         return;
924     detail::prepared_key key;
925     if(fh.mask)
926         detail::prepare_key(key, fh.key);
927     auto mb = db.prepare(data.size());
928     net::buffer_copy(mb,
929         net::const_buffer(
930             data.data(), data.size()));
931     if(fh.mask)
932         detail::mask_inplace(mb, key);
933     db.commit(data.size());
934 }
935 
936 template<class NextLayer, bool deflateSupported>
937 template<class DynamicBuffer>
938 void
939 stream<NextLayer, deflateSupported>::impl_type::
write_close(DynamicBuffer & db,close_reason const & cr)940 write_close(DynamicBuffer& db, close_reason const& cr)
941 {
942     using namespace boost::endian;
943     detail::frame_header fh;
944     fh.op = detail::opcode::close;
945     fh.fin = true;
946     fh.rsv1 = false;
947     fh.rsv2 = false;
948     fh.rsv3 = false;
949     fh.len = cr.code == close_code::none ?
950         0 : 2 + cr.reason.size();
951     if(role == role_type::client)
952     {
953         fh.mask = true;
954         fh.key = create_mask();
955     }
956     else
957     {
958         fh.mask = false;
959     }
960     detail::write(db, fh);
961     if(cr.code != close_code::none)
962     {
963         detail::prepared_key key;
964         if(fh.mask)
965             detail::prepare_key(key, fh.key);
966         {
967             auto code_be = endian::native_to_big<std::uint16_t>(cr.code);
968             auto mb = db.prepare(2);
969             net::buffer_copy(mb,
970                 net::const_buffer(&code_be, sizeof(code_be)));
971             if(fh.mask)
972                 detail::mask_inplace(mb, key);
973             db.commit(2);
974         }
975         if(! cr.reason.empty())
976         {
977             auto mb = db.prepare(cr.reason.size());
978             net::buffer_copy(mb,
979                 net::const_buffer(
980                     cr.reason.data(), cr.reason.size()));
981             if(fh.mask)
982                 detail::mask_inplace(mb, key);
983             db.commit(cr.reason.size());
984         }
985     }
986 }
987 
988 } // websocket
989 } // beast
990 } // boost
991 
992 #endif
993