2 * nghttp2 - HTTP/2 C Library
4 * Copyright (c) 2012 Tatsuhiro Tsujikawa
6 * Permission is hereby granted, free of charge, to any person obtaining
7 * a copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice shall be
15 * included in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 #ifndef SHRPX_DOWNSTREAM_H
26 #define SHRPX_DOWNSTREAM_H
39 #include <nghttp2/nghttp2.h>
43 #include "shrpx_io_control.h"
44 #include "shrpx_log_config.h"
47 #include "allocator.h"
49 using namespace nghttp2;
54 class DownstreamConnection;
56 struct DownstreamAddrGroup;
57 struct DownstreamAddr;
61 FieldStore(BlockAllocator &balloc, size_t headers_initial_capacity)
65 header_key_prev_(false),
66 trailer_key_prev_(false) {
67 headers_.reserve(headers_initial_capacity);
70 const HeaderRefs &headers() const { return headers_; }
71 const HeaderRefs &trailers() const { return trailers_; }
73 HeaderRefs &headers() { return headers_; }
75 const void add_extra_buffer_size(size_t n) { buffer_size_ += n; }
76 size_t buffer_size() const { return buffer_size_; }
78 size_t num_fields() const { return headers_.size() + trailers_.size(); }
80 // Returns pointer to the header field with the name |name|. If
81 // multiple header have |name| as name, return last occurrence from
82 // the beginning. If no such header is found, returns nullptr.
83 const HeaderRefs::value_type *header(int32_t token) const;
84 HeaderRefs::value_type *header(int32_t token);
85 // Returns pointer to the header field with the name |name|. If no
86 // such header is found, returns nullptr.
87 const HeaderRefs::value_type *header(const StringRef &name) const;
89 void add_header_token(const StringRef &name, const StringRef &value,
90 bool no_index, int32_t token);
92 // Adds header field name |name|. First, the copy of header field
93 // name pointed by name.c_str() of length name.size() is made, and
95 void alloc_add_header_name(const StringRef &name);
97 void append_last_header_key(const char *data, size_t len);
98 void append_last_header_value(const char *data, size_t len);
100 bool header_key_prev() const { return header_key_prev_; }
102 // Parses content-length, and records it in the field. If there are
103 // multiple Content-Length, returns -1.
104 int parse_content_length();
107 void clear_headers();
109 void add_trailer_token(const StringRef &name, const StringRef &value,
110 bool no_index, int32_t token);
112 // Adds trailer field name |name|. First, the copy of trailer field
113 // name pointed by name.c_str() of length name.size() is made, and
115 void alloc_add_trailer_name(const StringRef &name);
117 void append_last_trailer_key(const char *data, size_t len);
118 void append_last_trailer_value(const char *data, size_t len);
120 bool trailer_key_prev() const { return trailer_key_prev_; }
122 // erase_content_length_and_transfer_encoding erases content-length
123 // and transfer-encoding header fields.
124 void erase_content_length_and_transfer_encoding();
126 // content-length, -1 if it is unknown.
127 int64_t content_length;
130 BlockAllocator &balloc_;
132 // trailer fields. For HTTP/1.1, trailer fields are only included
133 // with chunked encoding. For HTTP/2, there is no such limit.
134 HeaderRefs trailers_;
135 // Sum of the length of name and value in headers_ and trailers_.
136 // This could also be increased by add_extra_buffer_size() to take
137 // into account for request URI in case of HTTP/1.x request.
139 bool header_key_prev_;
140 bool trailer_key_prev_;
143 // Protocols allowed in HTTP/2 :protocol header field.
144 enum class ConnectProto {
150 Request(BlockAllocator &balloc)
153 unconsumed_body_length(0),
157 connect_proto(ConnectProto::NONE),
158 upgrade_request(false),
159 http2_upgrade_seen(false),
160 connection_close(false),
161 http2_expect_body(false),
163 forwarded_once(false) {}
165 void consume(size_t len) {
166 assert(unconsumed_body_length >= len);
167 unconsumed_body_length -= len;
170 bool regular_connect_method() const {
171 return method == HTTP_CONNECT && connect_proto == ConnectProto::NONE;
174 bool extended_connect_method() const {
175 return connect_proto != ConnectProto::NONE;
179 // Timestamp when all request header fields are received.
180 std::shared_ptr<Timestamp> tstamp;
181 // Request scheme. For HTTP/2, this is :scheme header field value.
182 // For HTTP/1.1, this is deduced from URI or connection.
184 // Request authority. This is HTTP/2 :authority header field value
185 // or host header field value. We may deduce it from absolute-form
186 // HTTP/1 request. We also store authority-form HTTP/1 request.
187 // This could be empty if request comes from HTTP/1.0 without Host
188 // header field and origin-form.
190 // Request path, including query component. For HTTP/1.1, this is
191 // request-target. For HTTP/2, this is :path header field value.
192 // For CONNECT request, this is empty.
194 // This is original authority which cannot be changed by per-pattern
196 StringRef orig_authority;
197 // This is original path which cannot be changed by per-pattern
200 // the length of request body received so far
201 int64_t recv_body_length;
202 // The number of bytes not consumed by the application yet.
203 size_t unconsumed_body_length;
205 // HTTP major and minor version
206 int http_major, http_minor;
207 // connect_proto specified in HTTP/2 :protocol pseudo header field
208 // which enables extended CONNECT method. This field is also set if
209 // WebSocket upgrade is requested in h1 frontend for convenience.
210 ConnectProto connect_proto;
211 // Returns true if the request is HTTP upgrade (HTTP Upgrade or
212 // CONNECT method). Upgrade to HTTP/2 is excluded. For HTTP/2
213 // Upgrade, check get_http2_upgrade_request().
214 bool upgrade_request;
215 // true if h2c is seen in Upgrade header field.
216 bool http2_upgrade_seen;
217 bool connection_close;
218 // true if this is HTTP/2, and request body is expected. Note that
219 // we don't take into account HTTP method here.
220 bool http2_expect_body;
221 // true if request does not have any information about authority.
222 // This happens when: For HTTP/2 request, :authority is missing.
223 // For HTTP/1 request, origin or asterisk form is used.
225 // true if backend selection is done for request once.
226 // orig_authority and orig_path have the authority and path which
227 // are used for the first backend selection.
232 Response(BlockAllocator &balloc)
235 unconsumed_body_length(0),
239 connection_close(false),
240 headers_only(false) {}
242 void consume(size_t len) {
243 assert(unconsumed_body_length >= len);
244 unconsumed_body_length -= len;
247 // returns true if a resource denoted by scheme, authority, and path
248 // has already been pushed.
249 bool is_resource_pushed(const StringRef &scheme, const StringRef &authority,
250 const StringRef &path) const {
251 if (!pushed_resources) {
254 return std::find(std::begin(*pushed_resources), std::end(*pushed_resources),
255 std::make_tuple(scheme, authority, path)) !=
256 std::end(*pushed_resources);
259 // remember that a resource denoted by scheme, authority, and path
261 void resource_pushed(const StringRef &scheme, const StringRef &authority,
262 const StringRef &path) {
263 if (!pushed_resources) {
264 pushed_resources = std::make_unique<
265 std::vector<std::tuple<StringRef, StringRef, StringRef>>>();
267 pushed_resources->emplace_back(scheme, authority, path);
271 // array of the tuple of scheme, authority, and path of pushed
272 // resource. This is required because RFC 8297 says that server
273 // typically includes header fields appeared in non-final response
274 // header fields in final response header fields. Without checking
275 // that a particular resource has already been pushed, or not, we
276 // end up pushing the same resource at least twice. It is unknown
277 // that we should use more complex data structure (e.g., std::set)
278 // to find the resources faster.
279 std::unique_ptr<std::vector<std::tuple<StringRef, StringRef, StringRef>>>
281 // the length of response body received so far
282 int64_t recv_body_length;
283 // The number of bytes not consumed by the application yet. This is
284 // mainly for HTTP/2 backend.
285 size_t unconsumed_body_length;
287 unsigned int http_status;
288 int http_major, http_minor;
289 bool connection_close;
290 // true if response only consists of HEADERS, and it bears
291 // END_STREAM. This is used to tell Http2Upstream that it can send
292 // response with single HEADERS with END_STREAM flag only.
296 enum class DownstreamState {
303 // header contains invalid header field. We can safely send error
304 // response (502) to a client.
306 // header fields in HTTP/1 request exceed the configuration limit.
307 // This state is only transitioned from INITIAL state, and solely
308 // used to signal 431 status code to the client.
309 HTTP1_REQUEST_HEADER_TOO_LARGE,
312 enum class DispatchState {
322 Downstream(Upstream *upstream, MemchunkPool *mcpool, int32_t stream_id);
324 void reset_upstream(Upstream *upstream);
325 Upstream *get_upstream() const;
326 void set_stream_id(int32_t stream_id);
327 int32_t get_stream_id() const;
328 void set_assoc_stream_id(int32_t stream_id);
329 int32_t get_assoc_stream_id() const;
330 void pause_read(IOCtrlReason reason);
331 int resume_read(IOCtrlReason reason, size_t consumed);
332 void force_resume_read();
333 // Set stream ID for downstream HTTP2 connection.
334 void set_downstream_stream_id(int32_t stream_id);
335 int32_t get_downstream_stream_id() const;
337 int attach_downstream_connection(std::unique_ptr<DownstreamConnection> dconn);
338 void detach_downstream_connection();
339 DownstreamConnection *get_downstream_connection();
340 // Returns dconn_ and nullifies dconn_.
341 std::unique_ptr<DownstreamConnection> pop_downstream_connection();
343 // Returns true if output buffer is full. If underlying dconn_ is
344 // NULL, this function always returns false.
345 bool request_buf_full();
346 // Returns true if upgrade (HTTP Upgrade or CONNECT) is succeeded in
347 // h1 backend. This should not depend on inspect_http1_response().
348 void check_upgrade_fulfilled_http1();
349 // Returns true if upgrade (HTTP Upgrade or CONNECT) is succeeded in
351 void check_upgrade_fulfilled_http2();
352 // Returns true if the upgrade is succeeded as a result of the call
353 // check_upgrade_fulfilled_http*(). HTTP/2 Upgrade is excluded.
354 bool get_upgraded() const;
355 // Inspects HTTP/2 request.
356 void inspect_http2_request();
357 // Inspects HTTP/1 request. This checks whether the request is
358 // upgrade request and tranfer-encoding etc.
359 void inspect_http1_request();
360 // Returns true if the request is HTTP Upgrade for HTTP/2
361 bool get_http2_upgrade_request() const;
362 // Returns the value of HTTP2-Settings request header field.
363 StringRef get_http2_settings() const;
365 // downstream request API
366 const Request &request() const { return req_; }
367 Request &request() { return req_; }
369 // Count number of crumbled cookies
370 size_t count_crumble_request_cookie();
371 // Crumbles (split cookie by ";") in request_headers_ and adds them
372 // in |nva|. Headers::no_index is inherited.
373 void crumble_request_cookie(std::vector<nghttp2_nv> &nva);
374 // Assembles request cookies. The opposite operation against
375 // crumble_request_cookie().
376 StringRef assemble_request_cookie();
379 set_request_start_time(std::chrono::high_resolution_clock::time_point time);
380 const std::chrono::high_resolution_clock::time_point &
381 get_request_start_time() const;
382 int push_request_headers();
383 bool get_chunked_request() const;
384 void set_chunked_request(bool f);
385 int push_upload_data_chunk(const uint8_t *data, size_t datalen);
386 int end_upload_data();
387 // Validates that received request body length and content-length
389 bool validate_request_recv_body_length() const;
390 void set_request_downstream_host(const StringRef &host);
391 bool expect_response_body() const;
392 bool expect_response_trailer() const;
393 void set_request_state(DownstreamState state);
394 DownstreamState get_request_state() const;
395 DefaultMemchunks *get_request_buf();
396 void set_request_pending(bool f);
397 bool get_request_pending() const;
398 void set_request_header_sent(bool f);
399 bool get_request_header_sent() const;
400 // Returns true if request is ready to be submitted to downstream.
401 // When sending pending request, get_request_pending() should be
402 // checked too because this function may return true when
403 // get_request_pending() returns false.
404 bool request_submission_ready() const;
406 DefaultMemchunks *get_blocked_request_buf();
407 bool get_blocked_request_data_eof() const;
408 void set_blocked_request_data_eof(bool f);
410 // downstream response API
411 const Response &response() const { return resp_; }
412 Response &response() { return resp_; }
414 // Rewrites the location response header field.
415 void rewrite_location_response_header(const StringRef &upstream_scheme);
417 bool get_chunked_response() const;
418 void set_chunked_response(bool f);
420 void set_response_state(DownstreamState state);
421 DownstreamState get_response_state() const;
422 DefaultMemchunks *get_response_buf();
423 bool response_buf_full();
424 // Validates that received response body length and content-length
426 bool validate_response_recv_body_length() const;
427 uint32_t get_response_rst_stream_error_code() const;
428 void set_response_rst_stream_error_code(uint32_t error_code);
429 // Inspects HTTP/1 response. This checks tranfer-encoding etc.
430 void inspect_http1_response();
431 // Clears some of member variables for response.
432 void reset_response();
433 // True if the response is non-final (1xx status code). Note that
434 // if connection was upgraded, 101 status code is treated as final.
435 bool get_non_final_response() const;
436 // True if protocol version used by client supports non final
437 // response. Only HTTP/1.1 and HTTP/2 clients support it.
438 bool supports_non_final_response() const;
439 void set_expect_final_response(bool f);
440 bool get_expect_final_response() const;
442 // Call this method when there is incoming data in downstream
446 // Resets upstream read timer. If it is active, timeout value is
447 // reset. If it is not active, timer will be started.
448 void reset_upstream_rtimer();
449 // Resets upstream write timer. If it is active, timeout value is
450 // reset. If it is not active, timer will be started. This
451 // function also resets read timer if it has been started.
452 void reset_upstream_wtimer();
453 // Makes sure that upstream write timer is started. If it has been
454 // started, do nothing. Otherwise, write timer will be started.
455 void ensure_upstream_wtimer();
456 // Disables upstream read timer.
457 void disable_upstream_rtimer();
458 // Disables upstream write timer.
459 void disable_upstream_wtimer();
461 // Downstream timer functions. They works in a similar way just
462 // like the upstream timer function.
463 void reset_downstream_rtimer();
464 void reset_downstream_wtimer();
465 void ensure_downstream_wtimer();
466 void disable_downstream_rtimer();
467 void disable_downstream_wtimer();
469 // Returns true if accesslog can be written for this downstream.
470 bool accesslog_ready() const;
472 // Increment retry count
474 // true if retry attempt should not be done.
475 bool no_more_retry() const;
477 DispatchState get_dispatch_state() const;
478 void set_dispatch_state(DispatchState s);
480 void attach_blocked_link(BlockedLink *l);
481 BlockedLink *detach_blocked_link();
483 // Returns true if downstream_connection can be detached and reused.
484 bool can_detach_downstream_connection() const;
486 DefaultMemchunks pop_response_buf();
488 BlockAllocator &get_block_allocator();
490 void add_rcbuf(nghttp2_rcbuf *rcbuf);
493 set_downstream_addr_group(const std::shared_ptr<DownstreamAddrGroup> &group);
494 void set_addr(const DownstreamAddr *addr);
496 const DownstreamAddr *get_addr() const;
498 void set_accesslog_written(bool f);
500 // Finds affinity cookie from request header fields. The name of
501 // cookie is given in |name|. If an affinity cookie is found, it is
502 // assigned to a member function, and is returned. If it is not
503 // found, or is malformed, returns 0.
504 uint32_t find_affinity_cookie(const StringRef &name);
505 // Set |h| as affinity cookie.
506 void renew_affinity_cookie(uint32_t h);
507 // Returns affinity cookie to send. If it does not need to be sent,
508 // for example, because the value is retrieved from a request header
510 uint32_t get_affinity_cookie_to_send() const;
512 void set_ws_key(const StringRef &key);
514 bool get_expect_100_continue() const;
521 Downstream *dlnext, *dlprev;
523 // the length of response body sent to upstream client
524 int64_t response_sent_body_length;
527 BlockAllocator balloc_;
529 std::vector<nghttp2_rcbuf *> rcbufs_;
534 std::chrono::high_resolution_clock::time_point request_start_time_;
536 // host we requested to downstream. This is used to rewrite
537 // location header field to decide the location should be rewritten
539 StringRef request_downstream_host_;
541 // Data arrived in frontend before sending header fields to backend
542 // are stored in this buffer.
543 DefaultMemchunks blocked_request_buf_;
544 DefaultMemchunks request_buf_;
545 DefaultMemchunks response_buf_;
547 // The Sec-WebSocket-Key field sent to the peer. This field is used
548 // if frontend uses RFC 8441 WebSocket bootstrapping via HTTP/2.
551 ev_timer upstream_rtimer_;
552 ev_timer upstream_wtimer_;
554 ev_timer downstream_rtimer_;
555 ev_timer downstream_wtimer_;
558 std::unique_ptr<DownstreamConnection> dconn_;
560 // only used by HTTP/2 upstream
561 BlockedLink *blocked_link_;
562 // The backend address used to fulfill this request. These are for
564 std::shared_ptr<DownstreamAddrGroup> group_;
565 const DownstreamAddr *addr_;
566 // How many times we tried in backend connection
568 // The stream ID in frontend connection
570 // The associated stream ID in frontend connection if this is pushed
572 int32_t assoc_stream_id_;
573 // stream ID in backend connection
574 int32_t downstream_stream_id_;
575 // RST_STREAM error_code from downstream HTTP2 connection
576 uint32_t response_rst_stream_error_code_;
577 // An affinity cookie value.
578 uint32_t affinity_cookie_;
580 DownstreamState request_state_;
582 DownstreamState response_state_;
583 // only used by HTTP/2 upstream
584 DispatchState dispatch_state_;
585 // true if the connection is upgraded (HTTP Upgrade or CONNECT),
586 // excluding upgrade to HTTP/2.
588 // true if backend request uses chunked transfer-encoding
589 bool chunked_request_;
590 // true if response to client uses chunked transfer-encoding
591 bool chunked_response_;
592 // true if we have not got final response code
593 bool expect_final_response_;
594 // true if downstream request is pending because backend connection
595 // has not been established or should be checked before use;
596 // currently used only with HTTP/2 connection.
597 bool request_pending_;
598 // true if downstream request header is considered to be sent.
599 bool request_header_sent_;
600 // true if access.log has been written.
601 bool accesslog_written_;
602 // true if affinity cookie is generated for this request.
603 bool new_affinity_cookie_;
604 // true if eof is received from client before sending header fields
606 bool blocked_request_data_eof_;
607 // true if request contains "expect: 100-continue" header field.
608 bool expect_100_continue_;
613 #endif // SHRPX_DOWNSTREAM_H