1 /*
2  *
3  * Copyright 2015 gRPC authors.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  */
18 
19 #include <grpc/support/port_platform.h>
20 
21 #include <string.h>
22 
23 #include "absl/strings/str_cat.h"
24 #include "absl/strings/str_format.h"
25 
26 #include <grpc/support/alloc.h>
27 #include <grpc/support/log.h>
28 
29 #include "src/core/ext/transport/chttp2/transport/internal.h"
30 #include "src/core/lib/profiling/timers.h"
31 #include "src/core/lib/slice/slice_string_helpers.h"
32 #include "src/core/lib/slice/slice_utils.h"
33 #include "src/core/lib/transport/http2_errors.h"
34 #include "src/core/lib/transport/static_metadata.h"
35 #include "src/core/lib/transport/status_conversion.h"
36 #include "src/core/lib/transport/timeout_encoding.h"
37 
38 using grpc_core::HPackParser;
39 
40 static grpc_error_handle init_frame_parser(grpc_chttp2_transport* t);
41 static grpc_error_handle init_header_frame_parser(grpc_chttp2_transport* t,
42                                                   int is_continuation);
43 static grpc_error_handle init_data_frame_parser(grpc_chttp2_transport* t);
44 static grpc_error_handle init_rst_stream_parser(grpc_chttp2_transport* t);
45 static grpc_error_handle init_settings_frame_parser(grpc_chttp2_transport* t);
46 static grpc_error_handle init_window_update_frame_parser(
47     grpc_chttp2_transport* t);
48 static grpc_error_handle init_ping_parser(grpc_chttp2_transport* t);
49 static grpc_error_handle init_goaway_parser(grpc_chttp2_transport* t);
50 static grpc_error_handle init_non_header_skip_frame_parser(
51     grpc_chttp2_transport* t);
52 
53 static grpc_error_handle parse_frame_slice(grpc_chttp2_transport* t,
54                                            const grpc_slice& slice,
55                                            int is_last);
56 
grpc_chttp2_perform_read(grpc_chttp2_transport * t,const grpc_slice & slice)57 grpc_error_handle grpc_chttp2_perform_read(grpc_chttp2_transport* t,
58                                            const grpc_slice& slice) {
59   const uint8_t* beg = GRPC_SLICE_START_PTR(slice);
60   const uint8_t* end = GRPC_SLICE_END_PTR(slice);
61   const uint8_t* cur = beg;
62   grpc_error_handle err;
63 
64   if (cur == end) return GRPC_ERROR_NONE;
65 
66   switch (t->deframe_state) {
67     case GRPC_DTS_CLIENT_PREFIX_0:
68     case GRPC_DTS_CLIENT_PREFIX_1:
69     case GRPC_DTS_CLIENT_PREFIX_2:
70     case GRPC_DTS_CLIENT_PREFIX_3:
71     case GRPC_DTS_CLIENT_PREFIX_4:
72     case GRPC_DTS_CLIENT_PREFIX_5:
73     case GRPC_DTS_CLIENT_PREFIX_6:
74     case GRPC_DTS_CLIENT_PREFIX_7:
75     case GRPC_DTS_CLIENT_PREFIX_8:
76     case GRPC_DTS_CLIENT_PREFIX_9:
77     case GRPC_DTS_CLIENT_PREFIX_10:
78     case GRPC_DTS_CLIENT_PREFIX_11:
79     case GRPC_DTS_CLIENT_PREFIX_12:
80     case GRPC_DTS_CLIENT_PREFIX_13:
81     case GRPC_DTS_CLIENT_PREFIX_14:
82     case GRPC_DTS_CLIENT_PREFIX_15:
83     case GRPC_DTS_CLIENT_PREFIX_16:
84     case GRPC_DTS_CLIENT_PREFIX_17:
85     case GRPC_DTS_CLIENT_PREFIX_18:
86     case GRPC_DTS_CLIENT_PREFIX_19:
87     case GRPC_DTS_CLIENT_PREFIX_20:
88     case GRPC_DTS_CLIENT_PREFIX_21:
89     case GRPC_DTS_CLIENT_PREFIX_22:
90     case GRPC_DTS_CLIENT_PREFIX_23:
91       while (cur != end && t->deframe_state != GRPC_DTS_FH_0) {
92         if (*cur != GRPC_CHTTP2_CLIENT_CONNECT_STRING[t->deframe_state]) {
93           return GRPC_ERROR_CREATE_FROM_CPP_STRING(absl::StrFormat(
94               "Connect string mismatch: expected '%c' (%d) got '%c' (%d) "
95               "at byte %d",
96               GRPC_CHTTP2_CLIENT_CONNECT_STRING[t->deframe_state],
97               static_cast<int>(static_cast<uint8_t>(
98                   GRPC_CHTTP2_CLIENT_CONNECT_STRING[t->deframe_state])),
99               *cur, static_cast<int>(*cur), t->deframe_state));
100         }
101         ++cur;
102         // NOLINTNEXTLINE(bugprone-misplaced-widening-cast)
103         t->deframe_state = static_cast<grpc_chttp2_deframe_transport_state>(
104             1 + static_cast<int>(t->deframe_state));
105       }
106       if (cur == end) {
107         return GRPC_ERROR_NONE;
108       }
109     dts_fh_0:
110       ABSL_FALLTHROUGH_INTENDED;
111     case GRPC_DTS_FH_0:
112       GPR_DEBUG_ASSERT(cur < end);
113       t->incoming_frame_size = (static_cast<uint32_t>(*cur)) << 16;
114       if (++cur == end) {
115         t->deframe_state = GRPC_DTS_FH_1;
116         return GRPC_ERROR_NONE;
117       }
118       ABSL_FALLTHROUGH_INTENDED;
119     case GRPC_DTS_FH_1:
120       GPR_DEBUG_ASSERT(cur < end);
121       t->incoming_frame_size |= (static_cast<uint32_t>(*cur)) << 8;
122       if (++cur == end) {
123         t->deframe_state = GRPC_DTS_FH_2;
124         return GRPC_ERROR_NONE;
125       }
126       ABSL_FALLTHROUGH_INTENDED;
127     case GRPC_DTS_FH_2:
128       GPR_DEBUG_ASSERT(cur < end);
129       t->incoming_frame_size |= *cur;
130       if (++cur == end) {
131         t->deframe_state = GRPC_DTS_FH_3;
132         return GRPC_ERROR_NONE;
133       }
134       ABSL_FALLTHROUGH_INTENDED;
135     case GRPC_DTS_FH_3:
136       GPR_DEBUG_ASSERT(cur < end);
137       t->incoming_frame_type = *cur;
138       if (++cur == end) {
139         t->deframe_state = GRPC_DTS_FH_4;
140         return GRPC_ERROR_NONE;
141       }
142       ABSL_FALLTHROUGH_INTENDED;
143     case GRPC_DTS_FH_4:
144       GPR_DEBUG_ASSERT(cur < end);
145       t->incoming_frame_flags = *cur;
146       if (++cur == end) {
147         t->deframe_state = GRPC_DTS_FH_5;
148         return GRPC_ERROR_NONE;
149       }
150       ABSL_FALLTHROUGH_INTENDED;
151     case GRPC_DTS_FH_5:
152       GPR_DEBUG_ASSERT(cur < end);
153       t->incoming_stream_id = ((static_cast<uint32_t>(*cur)) & 0x7f) << 24;
154       if (++cur == end) {
155         t->deframe_state = GRPC_DTS_FH_6;
156         return GRPC_ERROR_NONE;
157       }
158       ABSL_FALLTHROUGH_INTENDED;
159     case GRPC_DTS_FH_6:
160       GPR_DEBUG_ASSERT(cur < end);
161       t->incoming_stream_id |= (static_cast<uint32_t>(*cur)) << 16;
162       if (++cur == end) {
163         t->deframe_state = GRPC_DTS_FH_7;
164         return GRPC_ERROR_NONE;
165       }
166       ABSL_FALLTHROUGH_INTENDED;
167     case GRPC_DTS_FH_7:
168       GPR_DEBUG_ASSERT(cur < end);
169       t->incoming_stream_id |= (static_cast<uint32_t>(*cur)) << 8;
170       if (++cur == end) {
171         t->deframe_state = GRPC_DTS_FH_8;
172         return GRPC_ERROR_NONE;
173       }
174       ABSL_FALLTHROUGH_INTENDED;
175     case GRPC_DTS_FH_8:
176       GPR_DEBUG_ASSERT(cur < end);
177       t->incoming_stream_id |= (static_cast<uint32_t>(*cur));
178       t->deframe_state = GRPC_DTS_FRAME;
179       err = init_frame_parser(t);
180       if (err != GRPC_ERROR_NONE) {
181         return err;
182       }
183       if (t->incoming_frame_size == 0) {
184         err = parse_frame_slice(t, grpc_empty_slice(), 1);
185         if (err != GRPC_ERROR_NONE) {
186           return err;
187         }
188         t->incoming_stream = nullptr;
189         if (++cur == end) {
190           t->deframe_state = GRPC_DTS_FH_0;
191           return GRPC_ERROR_NONE;
192         }
193         goto dts_fh_0; /* loop */
194       } else if (t->flow_control->flow_control_enabled() &&
195                  t->incoming_frame_size >
196                      t->settings[GRPC_ACKED_SETTINGS]
197                                 [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE]) {
198         return GRPC_ERROR_CREATE_FROM_CPP_STRING(
199             absl::StrFormat("Frame size %d is larger than max frame size %d",
200                             t->incoming_frame_size,
201                             t->settings[GRPC_ACKED_SETTINGS]
202                                        [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE]));
203       }
204       if (++cur == end) {
205         return GRPC_ERROR_NONE;
206       }
207       ABSL_FALLTHROUGH_INTENDED;
208     case GRPC_DTS_FRAME:
209       GPR_DEBUG_ASSERT(cur < end);
210       if (static_cast<uint32_t>(end - cur) == t->incoming_frame_size) {
211         err = parse_frame_slice(
212             t,
213             grpc_slice_sub_no_ref(slice, static_cast<size_t>(cur - beg),
214                                   static_cast<size_t>(end - beg)),
215             1);
216         if (err != GRPC_ERROR_NONE) {
217           return err;
218         }
219         t->deframe_state = GRPC_DTS_FH_0;
220         t->incoming_stream = nullptr;
221         return GRPC_ERROR_NONE;
222       } else if (static_cast<uint32_t>(end - cur) > t->incoming_frame_size) {
223         size_t cur_offset = static_cast<size_t>(cur - beg);
224         err = parse_frame_slice(
225             t,
226             grpc_slice_sub_no_ref(slice, cur_offset,
227                                   cur_offset + t->incoming_frame_size),
228             1);
229         if (err != GRPC_ERROR_NONE) {
230           return err;
231         }
232         cur += t->incoming_frame_size;
233         t->incoming_stream = nullptr;
234         goto dts_fh_0; /* loop */
235       } else {
236         err = parse_frame_slice(
237             t,
238             grpc_slice_sub_no_ref(slice, static_cast<size_t>(cur - beg),
239                                   static_cast<size_t>(end - beg)),
240             0);
241         if (err != GRPC_ERROR_NONE) {
242           return err;
243         }
244         t->incoming_frame_size -= static_cast<uint32_t>(end - cur);
245         return GRPC_ERROR_NONE;
246       }
247       GPR_UNREACHABLE_CODE(return GRPC_ERROR_NONE);
248   }
249 
250   GPR_UNREACHABLE_CODE(return GRPC_ERROR_NONE);
251 }
252 
init_frame_parser(grpc_chttp2_transport * t)253 static grpc_error_handle init_frame_parser(grpc_chttp2_transport* t) {
254   if (t->is_first_frame &&
255       t->incoming_frame_type != GRPC_CHTTP2_FRAME_SETTINGS) {
256     return GRPC_ERROR_CREATE_FROM_CPP_STRING(absl::StrCat(
257         "Expected SETTINGS frame as the first frame, got frame type ",
258         t->incoming_frame_type));
259   }
260   t->is_first_frame = false;
261   if (t->expect_continuation_stream_id != 0) {
262     if (t->incoming_frame_type != GRPC_CHTTP2_FRAME_CONTINUATION) {
263       return GRPC_ERROR_CREATE_FROM_CPP_STRING(
264           absl::StrFormat("Expected CONTINUATION frame, got frame type %02x",
265                           t->incoming_frame_type));
266     }
267     if (t->expect_continuation_stream_id != t->incoming_stream_id) {
268       return GRPC_ERROR_CREATE_FROM_CPP_STRING(absl::StrFormat(
269           "Expected CONTINUATION frame for grpc_chttp2_stream %08x, got "
270           "grpc_chttp2_stream %08x",
271           t->expect_continuation_stream_id, t->incoming_stream_id));
272     }
273     return init_header_frame_parser(t, 1);
274   }
275   switch (t->incoming_frame_type) {
276     case GRPC_CHTTP2_FRAME_DATA:
277       return init_data_frame_parser(t);
278     case GRPC_CHTTP2_FRAME_HEADER:
279       return init_header_frame_parser(t, 0);
280     case GRPC_CHTTP2_FRAME_CONTINUATION:
281       return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
282           "Unexpected CONTINUATION frame");
283     case GRPC_CHTTP2_FRAME_RST_STREAM:
284       return init_rst_stream_parser(t);
285     case GRPC_CHTTP2_FRAME_SETTINGS:
286       return init_settings_frame_parser(t);
287     case GRPC_CHTTP2_FRAME_WINDOW_UPDATE:
288       return init_window_update_frame_parser(t);
289     case GRPC_CHTTP2_FRAME_PING:
290       return init_ping_parser(t);
291     case GRPC_CHTTP2_FRAME_GOAWAY:
292       return init_goaway_parser(t);
293     default:
294       if (GRPC_TRACE_FLAG_ENABLED(grpc_http_trace)) {
295         gpr_log(GPR_ERROR, "Unknown frame type %02x", t->incoming_frame_type);
296       }
297       return init_non_header_skip_frame_parser(t);
298   }
299 }
300 
skip_parser(void *,grpc_chttp2_transport *,grpc_chttp2_stream *,const grpc_slice &,int)301 static grpc_error_handle skip_parser(void* /*parser*/,
302                                      grpc_chttp2_transport* /*t*/,
303                                      grpc_chttp2_stream* /*s*/,
304                                      const grpc_slice& /*slice*/,
305                                      int /*is_last*/) {
306   return GRPC_ERROR_NONE;
307 }
308 
skip_header(grpc_mdelem md)309 grpc_error_handle skip_header(grpc_mdelem md) {
310   GRPC_MDELEM_UNREF(md);
311   return GRPC_ERROR_NONE;
312 }
313 
hpack_boundary_type(grpc_chttp2_transport * t,bool is_eoh)314 static HPackParser::Boundary hpack_boundary_type(grpc_chttp2_transport* t,
315                                                  bool is_eoh) {
316   if (is_eoh) {
317     if (t->header_eof) {
318       return HPackParser::Boundary::EndOfStream;
319     } else {
320       return HPackParser::Boundary::EndOfHeaders;
321     }
322   } else {
323     return HPackParser::Boundary::None;
324   }
325 }
326 
hpack_parser_log_info(grpc_chttp2_transport * t,HPackParser::LogInfo::Type type)327 static HPackParser::LogInfo hpack_parser_log_info(
328     grpc_chttp2_transport* t, HPackParser::LogInfo::Type type) {
329   return HPackParser::LogInfo{
330       t->incoming_stream_id,
331       type,
332       t->is_client,
333   };
334 }
335 
init_header_skip_frame_parser(grpc_chttp2_transport * t,HPackParser::Priority priority_type)336 static grpc_error_handle init_header_skip_frame_parser(
337     grpc_chttp2_transport* t, HPackParser::Priority priority_type) {
338   bool is_eoh = t->expect_continuation_stream_id != 0;
339   t->parser = grpc_chttp2_header_parser_parse;
340   t->parser_data = &t->hpack_parser;
341   t->hpack_parser.BeginFrame(
342       nullptr,
343       t->settings[GRPC_ACKED_SETTINGS]
344                  [GRPC_CHTTP2_SETTINGS_MAX_HEADER_LIST_SIZE],
345       hpack_boundary_type(t, is_eoh), priority_type,
346       hpack_parser_log_info(t, HPackParser::LogInfo::kDontKnow));
347   return GRPC_ERROR_NONE;
348 }
349 
init_non_header_skip_frame_parser(grpc_chttp2_transport * t)350 static grpc_error_handle init_non_header_skip_frame_parser(
351     grpc_chttp2_transport* t) {
352   t->parser = skip_parser;
353   return GRPC_ERROR_NONE;
354 }
355 
grpc_chttp2_parsing_become_skip_parser(grpc_chttp2_transport * t)356 void grpc_chttp2_parsing_become_skip_parser(grpc_chttp2_transport* t) {
357   if (t->parser == grpc_chttp2_header_parser_parse) {
358     t->hpack_parser.StopBufferingFrame();
359   } else {
360     t->parser = skip_parser;
361   }
362 }
363 
init_data_frame_parser(grpc_chttp2_transport * t)364 static grpc_error_handle init_data_frame_parser(grpc_chttp2_transport* t) {
365   // Update BDP accounting since we have received a data frame.
366   grpc_core::BdpEstimator* bdp_est = t->flow_control->bdp_estimator();
367   if (bdp_est) {
368     if (t->bdp_ping_blocked) {
369       t->bdp_ping_blocked = false;
370       GRPC_CHTTP2_REF_TRANSPORT(t, "bdp_ping");
371       schedule_bdp_ping_locked(t);
372     }
373     bdp_est->AddIncomingBytes(t->incoming_frame_size);
374   }
375   grpc_chttp2_stream* s =
376       grpc_chttp2_parsing_lookup_stream(t, t->incoming_stream_id);
377   grpc_error_handle err = GRPC_ERROR_NONE;
378   grpc_core::chttp2::FlowControlAction action;
379   if (s == nullptr) {
380     err = t->flow_control->RecvData(t->incoming_frame_size);
381     action = t->flow_control->MakeAction();
382   } else {
383     err = s->flow_control->RecvData(t->incoming_frame_size);
384     action = s->flow_control->MakeAction();
385   }
386   grpc_chttp2_act_on_flowctl_action(action, t, s);
387   if (err != GRPC_ERROR_NONE) {
388     goto error_handler;
389   }
390   if (s == nullptr) {
391     return init_non_header_skip_frame_parser(t);
392   }
393   s->received_bytes += t->incoming_frame_size;
394   s->stats.incoming.framing_bytes += 9;
395   if (err == GRPC_ERROR_NONE && s->read_closed) {
396     return init_non_header_skip_frame_parser(t);
397   }
398   if (err == GRPC_ERROR_NONE) {
399     err = grpc_chttp2_data_parser_begin_frame(
400         &s->data_parser, t->incoming_frame_flags, s->id, s);
401   }
402 error_handler:
403   intptr_t unused;
404   if (err == GRPC_ERROR_NONE) {
405     t->incoming_stream = s;
406     /* t->parser = grpc_chttp2_data_parser_parse;*/
407     t->parser = grpc_chttp2_data_parser_parse;
408     t->parser_data = &s->data_parser;
409     t->ping_state.last_ping_sent_time = GRPC_MILLIS_INF_PAST;
410     return GRPC_ERROR_NONE;
411   } else if (grpc_error_get_int(err, GRPC_ERROR_INT_STREAM_ID, &unused)) {
412     /* handle stream errors by closing the stream */
413     if (s != nullptr) {
414       grpc_chttp2_mark_stream_closed(t, s, true, false, err);
415     }
416     grpc_chttp2_add_rst_stream_to_next_write(t, t->incoming_stream_id,
417                                              GRPC_HTTP2_PROTOCOL_ERROR,
418                                              &s->stats.outgoing);
419     return init_non_header_skip_frame_parser(t);
420   } else {
421     return err;
422   }
423 }
424 
init_header_frame_parser(grpc_chttp2_transport * t,int is_continuation)425 static grpc_error_handle init_header_frame_parser(grpc_chttp2_transport* t,
426                                                   int is_continuation) {
427   const bool is_eoh =
428       (t->incoming_frame_flags & GRPC_CHTTP2_DATA_FLAG_END_HEADERS) != 0;
429   grpc_chttp2_stream* s;
430 
431   /* TODO(ctiller): when to increment header_frames_received? */
432 
433   if (is_eoh) {
434     t->expect_continuation_stream_id = 0;
435   } else {
436     t->expect_continuation_stream_id = t->incoming_stream_id;
437   }
438 
439   if (!is_continuation) {
440     t->header_eof =
441         (t->incoming_frame_flags & GRPC_CHTTP2_DATA_FLAG_END_STREAM) != 0;
442   }
443 
444   const auto priority_type = !is_continuation && (t->incoming_frame_flags &
445                                                   GRPC_CHTTP2_FLAG_HAS_PRIORITY)
446                                  ? HPackParser::Priority::Included
447                                  : HPackParser::Priority::None;
448 
449   t->ping_state.last_ping_sent_time = GRPC_MILLIS_INF_PAST;
450 
451   /* could be a new grpc_chttp2_stream or an existing grpc_chttp2_stream */
452   s = grpc_chttp2_parsing_lookup_stream(t, t->incoming_stream_id);
453   if (s == nullptr) {
454     if (GPR_UNLIKELY(is_continuation)) {
455       GRPC_CHTTP2_IF_TRACING(
456           gpr_log(GPR_ERROR,
457                   "grpc_chttp2_stream disbanded before CONTINUATION received"));
458       return init_header_skip_frame_parser(t, priority_type);
459     }
460     if (t->is_client) {
461       if (GPR_LIKELY((t->incoming_stream_id & 1) &&
462                      t->incoming_stream_id < t->next_stream_id)) {
463         /* this is an old (probably cancelled) grpc_chttp2_stream */
464       } else {
465         GRPC_CHTTP2_IF_TRACING(gpr_log(
466             GPR_ERROR, "ignoring new grpc_chttp2_stream creation on client"));
467       }
468       return init_header_skip_frame_parser(t, priority_type);
469     } else if (GPR_UNLIKELY(t->last_new_stream_id >= t->incoming_stream_id)) {
470       GRPC_CHTTP2_IF_TRACING(gpr_log(
471           GPR_ERROR,
472           "ignoring out of order new grpc_chttp2_stream request on server; "
473           "last grpc_chttp2_stream "
474           "id=%d, new grpc_chttp2_stream id=%d",
475           t->last_new_stream_id, t->incoming_stream_id));
476       return init_header_skip_frame_parser(t, priority_type);
477     } else if (GPR_UNLIKELY((t->incoming_stream_id & 1) == 0)) {
478       GRPC_CHTTP2_IF_TRACING(gpr_log(
479           GPR_ERROR,
480           "ignoring grpc_chttp2_stream with non-client generated index %d",
481           t->incoming_stream_id));
482       return init_header_skip_frame_parser(t, priority_type);
483     } else if (GPR_UNLIKELY(
484                    grpc_chttp2_stream_map_size(&t->stream_map) >=
485                    t->settings[GRPC_ACKED_SETTINGS]
486                               [GRPC_CHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS])) {
487       return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Max stream count exceeded");
488     }
489     t->last_new_stream_id = t->incoming_stream_id;
490     s = t->incoming_stream =
491         grpc_chttp2_parsing_accept_stream(t, t->incoming_stream_id);
492     if (GPR_UNLIKELY(s == nullptr)) {
493       GRPC_CHTTP2_IF_TRACING(
494           gpr_log(GPR_ERROR, "grpc_chttp2_stream not accepted"));
495       return init_header_skip_frame_parser(t, priority_type);
496     }
497     if (t->channelz_socket != nullptr) {
498       t->channelz_socket->RecordStreamStartedFromRemote();
499     }
500   } else {
501     t->incoming_stream = s;
502   }
503   GPR_DEBUG_ASSERT(s != nullptr);
504   s->stats.incoming.framing_bytes += 9;
505   if (GPR_UNLIKELY(s->read_closed)) {
506     GRPC_CHTTP2_IF_TRACING(gpr_log(
507         GPR_ERROR, "skipping already closed grpc_chttp2_stream header"));
508     t->incoming_stream = nullptr;
509     return init_header_skip_frame_parser(t, priority_type);
510   }
511   t->parser = grpc_chttp2_header_parser_parse;
512   t->parser_data = &t->hpack_parser;
513   if (t->header_eof) {
514     s->eos_received = true;
515   }
516   grpc_metadata_batch* incoming_metadata_buffer = nullptr;
517   HPackParser::LogInfo::Type frame_type = HPackParser::LogInfo::kDontKnow;
518   switch (s->header_frames_received) {
519     case 0:
520       if (t->is_client && t->header_eof) {
521         GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "parsing Trailers-Only"));
522         if (s->trailing_metadata_available != nullptr) {
523           *s->trailing_metadata_available = true;
524         }
525         incoming_metadata_buffer = &s->trailing_metadata_buffer;
526         frame_type = HPackParser::LogInfo::kTrailers;
527       } else {
528         GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "parsing initial_metadata"));
529         incoming_metadata_buffer = &s->initial_metadata_buffer;
530         frame_type = HPackParser::LogInfo::kHeaders;
531       }
532       break;
533     case 1:
534       GRPC_CHTTP2_IF_TRACING(gpr_log(GPR_INFO, "parsing trailing_metadata"));
535       incoming_metadata_buffer = &s->trailing_metadata_buffer;
536       frame_type = HPackParser::LogInfo::kTrailers;
537       break;
538     case 2:
539       gpr_log(GPR_ERROR, "too many header frames received");
540       return init_header_skip_frame_parser(t, priority_type);
541   }
542   t->hpack_parser.BeginFrame(
543       incoming_metadata_buffer,
544       t->settings[GRPC_ACKED_SETTINGS]
545                  [GRPC_CHTTP2_SETTINGS_MAX_HEADER_LIST_SIZE],
546       hpack_boundary_type(t, is_eoh), priority_type,
547       hpack_parser_log_info(t, frame_type));
548   return GRPC_ERROR_NONE;
549 }
550 
init_window_update_frame_parser(grpc_chttp2_transport * t)551 static grpc_error_handle init_window_update_frame_parser(
552     grpc_chttp2_transport* t) {
553   grpc_error_handle err = grpc_chttp2_window_update_parser_begin_frame(
554       &t->simple.window_update, t->incoming_frame_size,
555       t->incoming_frame_flags);
556   if (err != GRPC_ERROR_NONE) return err;
557   if (t->incoming_stream_id != 0) {
558     grpc_chttp2_stream* s = t->incoming_stream =
559         grpc_chttp2_parsing_lookup_stream(t, t->incoming_stream_id);
560     if (s == nullptr) {
561       return init_non_header_skip_frame_parser(t);
562     }
563     s->stats.incoming.framing_bytes += 9;
564   }
565   t->parser = grpc_chttp2_window_update_parser_parse;
566   t->parser_data = &t->simple.window_update;
567   return GRPC_ERROR_NONE;
568 }
569 
init_ping_parser(grpc_chttp2_transport * t)570 static grpc_error_handle init_ping_parser(grpc_chttp2_transport* t) {
571   grpc_error_handle err = grpc_chttp2_ping_parser_begin_frame(
572       &t->simple.ping, t->incoming_frame_size, t->incoming_frame_flags);
573   if (err != GRPC_ERROR_NONE) return err;
574   t->parser = grpc_chttp2_ping_parser_parse;
575   t->parser_data = &t->simple.ping;
576   return GRPC_ERROR_NONE;
577 }
578 
init_rst_stream_parser(grpc_chttp2_transport * t)579 static grpc_error_handle init_rst_stream_parser(grpc_chttp2_transport* t) {
580   grpc_error_handle err = grpc_chttp2_rst_stream_parser_begin_frame(
581       &t->simple.rst_stream, t->incoming_frame_size, t->incoming_frame_flags);
582   if (err != GRPC_ERROR_NONE) return err;
583   grpc_chttp2_stream* s = t->incoming_stream =
584       grpc_chttp2_parsing_lookup_stream(t, t->incoming_stream_id);
585   if (!t->incoming_stream) {
586     return init_non_header_skip_frame_parser(t);
587   }
588   s->stats.incoming.framing_bytes += 9;
589   t->parser = grpc_chttp2_rst_stream_parser_parse;
590   t->parser_data = &t->simple.rst_stream;
591   return GRPC_ERROR_NONE;
592 }
593 
init_goaway_parser(grpc_chttp2_transport * t)594 static grpc_error_handle init_goaway_parser(grpc_chttp2_transport* t) {
595   grpc_error_handle err = grpc_chttp2_goaway_parser_begin_frame(
596       &t->goaway_parser, t->incoming_frame_size, t->incoming_frame_flags);
597   if (err != GRPC_ERROR_NONE) return err;
598   t->parser = grpc_chttp2_goaway_parser_parse;
599   t->parser_data = &t->goaway_parser;
600   return GRPC_ERROR_NONE;
601 }
602 
init_settings_frame_parser(grpc_chttp2_transport * t)603 static grpc_error_handle init_settings_frame_parser(grpc_chttp2_transport* t) {
604   if (t->incoming_stream_id != 0) {
605     return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
606         "Settings frame received for grpc_chttp2_stream");
607   }
608 
609   grpc_error_handle err = grpc_chttp2_settings_parser_begin_frame(
610       &t->simple.settings, t->incoming_frame_size, t->incoming_frame_flags,
611       t->settings[GRPC_PEER_SETTINGS]);
612   if (err != GRPC_ERROR_NONE) {
613     return err;
614   }
615   if (t->incoming_frame_flags & GRPC_CHTTP2_FLAG_ACK) {
616     memcpy(t->settings[GRPC_ACKED_SETTINGS], t->settings[GRPC_SENT_SETTINGS],
617            GRPC_CHTTP2_NUM_SETTINGS * sizeof(uint32_t));
618     t->hpack_parser.hpack_table()->SetMaxBytes(
619         t->settings[GRPC_ACKED_SETTINGS]
620                    [GRPC_CHTTP2_SETTINGS_HEADER_TABLE_SIZE]);
621     t->sent_local_settings = false;
622   }
623   t->parser = grpc_chttp2_settings_parser_parse;
624   t->parser_data = &t->simple.settings;
625   return GRPC_ERROR_NONE;
626 }
627 
parse_frame_slice(grpc_chttp2_transport * t,const grpc_slice & slice,int is_last)628 static grpc_error_handle parse_frame_slice(grpc_chttp2_transport* t,
629                                            const grpc_slice& slice,
630                                            int is_last) {
631   grpc_chttp2_stream* s = t->incoming_stream;
632   grpc_error_handle err = t->parser(t->parser_data, t, s, slice, is_last);
633   intptr_t unused;
634   if (GPR_LIKELY(err == GRPC_ERROR_NONE)) {
635     return err;
636   } else if (grpc_error_get_int(err, GRPC_ERROR_INT_STREAM_ID, &unused)) {
637     if (GRPC_TRACE_FLAG_ENABLED(grpc_http_trace)) {
638       gpr_log(GPR_ERROR, "%s", grpc_error_std_string(err).c_str());
639     }
640     grpc_chttp2_parsing_become_skip_parser(t);
641     if (s) {
642       s->forced_close_error = err;
643       grpc_chttp2_add_rst_stream_to_next_write(t, t->incoming_stream_id,
644                                                GRPC_HTTP2_PROTOCOL_ERROR,
645                                                &s->stats.outgoing);
646     } else {
647       GRPC_ERROR_UNREF(err);
648     }
649   }
650   return err;
651 }
652