1 /*
2  * Copyright (C) Nginx, Inc.
3  * Copyright (C) Valentin V. Bartenev
4  */
5 
6 
7 #ifndef _NGX_HTTP_V2_H_INCLUDED_
8 #define _NGX_HTTP_V2_H_INCLUDED_
9 
10 
11 #include <ngx_config.h>
12 #include <ngx_core.h>
13 #include <ngx_http.h>
14 
15 
16 #define NGX_HTTP_V2_ALPN_ADVERTISE       "\x02h2"
17 #define NGX_HTTP_V2_NPN_ADVERTISE        NGX_HTTP_V2_ALPN_ADVERTISE
18 
19 #define NGX_HTTP_V2_STATE_BUFFER_SIZE    16
20 
21 #define NGX_HTTP_V2_DEFAULT_FRAME_SIZE   (1 << 14)
22 #define NGX_HTTP_V2_MAX_FRAME_SIZE       ((1 << 24) - 1)
23 
24 #define NGX_HTTP_V2_INT_OCTETS           4
25 #define NGX_HTTP_V2_MAX_FIELD                                                 \
26     (127 + (1 << (NGX_HTTP_V2_INT_OCTETS - 1) * 7) - 1)
27 
28 #define NGX_HTTP_V2_STREAM_ID_SIZE       4
29 
30 #define NGX_HTTP_V2_FRAME_HEADER_SIZE    9
31 
32 /* frame types */
33 #define NGX_HTTP_V2_DATA_FRAME           0x0
34 #define NGX_HTTP_V2_HEADERS_FRAME        0x1
35 #define NGX_HTTP_V2_PRIORITY_FRAME       0x2
36 #define NGX_HTTP_V2_RST_STREAM_FRAME     0x3
37 #define NGX_HTTP_V2_SETTINGS_FRAME       0x4
38 #define NGX_HTTP_V2_PUSH_PROMISE_FRAME   0x5
39 #define NGX_HTTP_V2_PING_FRAME           0x6
40 #define NGX_HTTP_V2_GOAWAY_FRAME         0x7
41 #define NGX_HTTP_V2_WINDOW_UPDATE_FRAME  0x8
42 #define NGX_HTTP_V2_CONTINUATION_FRAME   0x9
43 
44 /* frame flags */
45 #define NGX_HTTP_V2_NO_FLAG              0x00
46 #define NGX_HTTP_V2_ACK_FLAG             0x01
47 #define NGX_HTTP_V2_END_STREAM_FLAG      0x01
48 #define NGX_HTTP_V2_END_HEADERS_FLAG     0x04
49 #define NGX_HTTP_V2_PADDED_FLAG          0x08
50 #define NGX_HTTP_V2_PRIORITY_FLAG        0x20
51 
52 #define NGX_HTTP_V2_MAX_WINDOW           ((1U << 31) - 1)
53 #define NGX_HTTP_V2_DEFAULT_WINDOW       65535
54 
55 #define NGX_HTTP_V2_DEFAULT_WEIGHT       16
56 
57 
58 typedef struct ngx_http_v2_connection_s   ngx_http_v2_connection_t;
59 typedef struct ngx_http_v2_node_s         ngx_http_v2_node_t;
60 typedef struct ngx_http_v2_out_frame_s    ngx_http_v2_out_frame_t;
61 
62 
63 typedef u_char *(*ngx_http_v2_handler_pt) (ngx_http_v2_connection_t *h2c,
64     u_char *pos, u_char *end);
65 
66 
67 typedef struct {
68     ngx_str_t                        name;
69     ngx_str_t                        value;
70 } ngx_http_v2_header_t;
71 
72 
73 typedef struct {
74     ngx_uint_t                       sid;
75     size_t                           length;
76     size_t                           padding;
77     unsigned                         flags:8;
78 
79     unsigned                         incomplete:1;
80     unsigned                         keep_pool:1;
81 
82     /* HPACK */
83     unsigned                         parse_name:1;
84     unsigned                         parse_value:1;
85     unsigned                         index:1;
86     ngx_http_v2_header_t             header;
87     size_t                           header_limit;
88     u_char                           field_state;
89     u_char                          *field_start;
90     u_char                          *field_end;
91     size_t                           field_rest;
92     ngx_pool_t                      *pool;
93 
94     ngx_http_v2_stream_t            *stream;
95 
96     u_char                           buffer[NGX_HTTP_V2_STATE_BUFFER_SIZE];
97     size_t                           buffer_used;
98     ngx_http_v2_handler_pt           handler;
99 } ngx_http_v2_state_t;
100 
101 
102 
103 typedef struct {
104     ngx_http_v2_header_t           **entries;
105 
106     ngx_uint_t                       added;
107     ngx_uint_t                       deleted;
108     ngx_uint_t                       reused;
109     ngx_uint_t                       allocated;
110 
111     size_t                           size;
112     size_t                           free;
113     u_char                          *storage;
114     u_char                          *pos;
115 } ngx_http_v2_hpack_t;
116 
117 
118 struct ngx_http_v2_connection_s {
119     ngx_connection_t                *connection;
120     ngx_http_connection_t           *http_connection;
121 
122     ngx_uint_t                       processing;
123     ngx_uint_t                       frames;
124     ngx_uint_t                       idle;
125     ngx_uint_t                       priority_limit;
126 
127     ngx_uint_t                       pushing;
128     ngx_uint_t                       concurrent_pushes;
129 
130     size_t                           send_window;
131     size_t                           recv_window;
132     size_t                           init_window;
133 
134     size_t                           frame_size;
135 
136     ngx_queue_t                      waiting;
137 
138     ngx_http_v2_state_t              state;
139 
140     ngx_http_v2_hpack_t              hpack;
141 
142     ngx_pool_t                      *pool;
143 
144     ngx_http_v2_out_frame_t         *free_frames;
145     ngx_connection_t                *free_fake_connections;
146 
147     ngx_http_v2_node_t             **streams_index;
148 
149     ngx_http_v2_out_frame_t         *last_out;
150 
151     ngx_queue_t                      dependencies;
152     ngx_queue_t                      closed;
153 
154     ngx_uint_t                       last_sid;
155     ngx_uint_t                       last_push;
156 
157     unsigned                         closed_nodes:8;
158     unsigned                         settings_ack:1;
159     unsigned                         table_update:1;
160     unsigned                         blocked:1;
161     unsigned                         goaway:1;
162     unsigned                         push_disabled:1;
163 };
164 
165 
166 struct ngx_http_v2_node_s {
167     ngx_uint_t                       id;
168     ngx_http_v2_node_t              *index;
169     ngx_http_v2_node_t              *parent;
170     ngx_queue_t                      queue;
171     ngx_queue_t                      children;
172     ngx_queue_t                      reuse;
173     ngx_uint_t                       rank;
174     ngx_uint_t                       weight;
175     double                           rel_weight;
176     ngx_http_v2_stream_t            *stream;
177 };
178 
179 
180 struct ngx_http_v2_stream_s {
181     ngx_http_request_t              *request;
182     ngx_http_v2_connection_t        *connection;
183     ngx_http_v2_node_t              *node;
184 
185     ngx_uint_t                       queued;
186 
187     /*
188      * A change to SETTINGS_INITIAL_WINDOW_SIZE could cause the
189      * send_window to become negative, hence it's signed.
190      */
191     ssize_t                          send_window;
192     size_t                           recv_window;
193 
194     ngx_buf_t                       *preread;
195 
196     ngx_uint_t                       frames;
197 
198     ngx_http_v2_out_frame_t         *free_frames;
199     ngx_chain_t                     *free_frame_headers;
200     ngx_chain_t                     *free_bufs;
201 
202     ngx_queue_t                      queue;
203 
204     ngx_array_t                     *cookies;
205 
206     ngx_pool_t                      *pool;
207 
208     unsigned                         waiting:1;
209     unsigned                         blocked:1;
210     unsigned                         exhausted:1;
211     unsigned                         in_closed:1;
212     unsigned                         out_closed:1;
213     unsigned                         rst_sent:1;
214     unsigned                         no_flow_control:1;
215     unsigned                         skip_data:1;
216 };
217 
218 
219 struct ngx_http_v2_out_frame_s {
220     ngx_http_v2_out_frame_t         *next;
221     ngx_chain_t                     *first;
222     ngx_chain_t                     *last;
223     ngx_int_t                      (*handler)(ngx_http_v2_connection_t *h2c,
224                                         ngx_http_v2_out_frame_t *frame);
225 
226     ngx_http_v2_stream_t            *stream;
227     size_t                           length;
228 
229     unsigned                         blocked:1;
230     unsigned                         fin:1;
231 };
232 
233 
234 static ngx_inline void
ngx_http_v2_queue_frame(ngx_http_v2_connection_t * h2c,ngx_http_v2_out_frame_t * frame)235 ngx_http_v2_queue_frame(ngx_http_v2_connection_t *h2c,
236     ngx_http_v2_out_frame_t *frame)
237 {
238     ngx_http_v2_out_frame_t  **out;
239 
240     for (out = &h2c->last_out; *out; out = &(*out)->next) {
241 
242         if ((*out)->blocked || (*out)->stream == NULL) {
243             break;
244         }
245 
246         if ((*out)->stream->node->rank < frame->stream->node->rank
247             || ((*out)->stream->node->rank == frame->stream->node->rank
248                 && (*out)->stream->node->rel_weight
249                    >= frame->stream->node->rel_weight))
250         {
251             break;
252         }
253     }
254 
255     frame->next = *out;
256     *out = frame;
257 }
258 
259 
260 static ngx_inline void
ngx_http_v2_queue_blocked_frame(ngx_http_v2_connection_t * h2c,ngx_http_v2_out_frame_t * frame)261 ngx_http_v2_queue_blocked_frame(ngx_http_v2_connection_t *h2c,
262     ngx_http_v2_out_frame_t *frame)
263 {
264     ngx_http_v2_out_frame_t  **out;
265 
266     for (out = &h2c->last_out; *out; out = &(*out)->next) {
267 
268         if ((*out)->blocked || (*out)->stream == NULL) {
269             break;
270         }
271     }
272 
273     frame->next = *out;
274     *out = frame;
275 }
276 
277 
278 static ngx_inline void
ngx_http_v2_queue_ordered_frame(ngx_http_v2_connection_t * h2c,ngx_http_v2_out_frame_t * frame)279 ngx_http_v2_queue_ordered_frame(ngx_http_v2_connection_t *h2c,
280     ngx_http_v2_out_frame_t *frame)
281 {
282     frame->next = h2c->last_out;
283     h2c->last_out = frame;
284 }
285 
286 
287 void ngx_http_v2_init(ngx_event_t *rev);
288 
289 ngx_int_t ngx_http_v2_read_request_body(ngx_http_request_t *r);
290 ngx_int_t ngx_http_v2_read_unbuffered_request_body(ngx_http_request_t *r);
291 
292 ngx_http_v2_stream_t *ngx_http_v2_push_stream(ngx_http_v2_stream_t *parent,
293     ngx_str_t *path);
294 
295 void ngx_http_v2_close_stream(ngx_http_v2_stream_t *stream, ngx_int_t rc);
296 
297 ngx_int_t ngx_http_v2_send_output_queue(ngx_http_v2_connection_t *h2c);
298 
299 
300 ngx_str_t *ngx_http_v2_get_static_name(ngx_uint_t index);
301 ngx_str_t *ngx_http_v2_get_static_value(ngx_uint_t index);
302 
303 ngx_int_t ngx_http_v2_get_indexed_header(ngx_http_v2_connection_t *h2c,
304     ngx_uint_t index, ngx_uint_t name_only);
305 ngx_int_t ngx_http_v2_add_header(ngx_http_v2_connection_t *h2c,
306     ngx_http_v2_header_t *header);
307 ngx_int_t ngx_http_v2_table_size(ngx_http_v2_connection_t *h2c, size_t size);
308 
309 
310 ngx_int_t ngx_http_v2_huff_decode(u_char *state, u_char *src, size_t len,
311     u_char **dst, ngx_uint_t last, ngx_log_t *log);
312 size_t ngx_http_v2_huff_encode(u_char *src, size_t len, u_char *dst,
313     ngx_uint_t lower);
314 
315 
316 #define ngx_http_v2_prefix(bits)  ((1 << (bits)) - 1)
317 
318 
319 #if (NGX_HAVE_NONALIGNED)
320 
321 #define ngx_http_v2_parse_uint16(p)  ntohs(*(uint16_t *) (p))
322 #define ngx_http_v2_parse_uint32(p)  ntohl(*(uint32_t *) (p))
323 
324 #else
325 
326 #define ngx_http_v2_parse_uint16(p)  ((p)[0] << 8 | (p)[1])
327 #define ngx_http_v2_parse_uint32(p)                                           \
328     ((uint32_t) (p)[0] << 24 | (p)[1] << 16 | (p)[2] << 8 | (p)[3])
329 
330 #endif
331 
332 #define ngx_http_v2_parse_length(p)  ((p) >> 8)
333 #define ngx_http_v2_parse_type(p)    ((p) & 0xff)
334 #define ngx_http_v2_parse_sid(p)     (ngx_http_v2_parse_uint32(p) & 0x7fffffff)
335 #define ngx_http_v2_parse_window(p)  (ngx_http_v2_parse_uint32(p) & 0x7fffffff)
336 
337 
338 #define ngx_http_v2_write_uint16_aligned(p, s)                                \
339     (*(uint16_t *) (p) = htons((uint16_t) (s)), (p) + sizeof(uint16_t))
340 #define ngx_http_v2_write_uint32_aligned(p, s)                                \
341     (*(uint32_t *) (p) = htonl((uint32_t) (s)), (p) + sizeof(uint32_t))
342 
343 #if (NGX_HAVE_NONALIGNED)
344 
345 #define ngx_http_v2_write_uint16  ngx_http_v2_write_uint16_aligned
346 #define ngx_http_v2_write_uint32  ngx_http_v2_write_uint32_aligned
347 
348 #else
349 
350 #define ngx_http_v2_write_uint16(p, s)                                        \
351     ((p)[0] = (u_char) ((s) >> 8),                                            \
352      (p)[1] = (u_char)  (s),                                                  \
353      (p) + sizeof(uint16_t))
354 
355 #define ngx_http_v2_write_uint32(p, s)                                        \
356     ((p)[0] = (u_char) ((s) >> 24),                                           \
357      (p)[1] = (u_char) ((s) >> 16),                                           \
358      (p)[2] = (u_char) ((s) >> 8),                                            \
359      (p)[3] = (u_char)  (s),                                                  \
360      (p) + sizeof(uint32_t))
361 
362 #endif
363 
364 #define ngx_http_v2_write_len_and_type(p, l, t)                               \
365     ngx_http_v2_write_uint32_aligned(p, (l) << 8 | (t))
366 
367 #define ngx_http_v2_write_sid  ngx_http_v2_write_uint32
368 
369 
370 #define ngx_http_v2_indexed(i)      (128 + (i))
371 #define ngx_http_v2_inc_indexed(i)  (64 + (i))
372 
373 #define ngx_http_v2_write_name(dst, src, len, tmp)                            \
374     ngx_http_v2_string_encode(dst, src, len, tmp, 1)
375 #define ngx_http_v2_write_value(dst, src, len, tmp)                           \
376     ngx_http_v2_string_encode(dst, src, len, tmp, 0)
377 
378 #define NGX_HTTP_V2_ENCODE_RAW            0
379 #define NGX_HTTP_V2_ENCODE_HUFF           0x80
380 
381 #define NGX_HTTP_V2_AUTHORITY_INDEX       1
382 
383 #define NGX_HTTP_V2_METHOD_INDEX          2
384 #define NGX_HTTP_V2_METHOD_GET_INDEX      2
385 #define NGX_HTTP_V2_METHOD_POST_INDEX     3
386 
387 #define NGX_HTTP_V2_PATH_INDEX            4
388 #define NGX_HTTP_V2_PATH_ROOT_INDEX       4
389 
390 #define NGX_HTTP_V2_SCHEME_HTTP_INDEX     6
391 #define NGX_HTTP_V2_SCHEME_HTTPS_INDEX    7
392 
393 #define NGX_HTTP_V2_STATUS_INDEX          8
394 #define NGX_HTTP_V2_STATUS_200_INDEX      8
395 #define NGX_HTTP_V2_STATUS_204_INDEX      9
396 #define NGX_HTTP_V2_STATUS_206_INDEX      10
397 #define NGX_HTTP_V2_STATUS_304_INDEX      11
398 #define NGX_HTTP_V2_STATUS_400_INDEX      12
399 #define NGX_HTTP_V2_STATUS_404_INDEX      13
400 #define NGX_HTTP_V2_STATUS_500_INDEX      14
401 
402 #define NGX_HTTP_V2_ACCEPT_ENCODING_INDEX 16
403 #define NGX_HTTP_V2_ACCEPT_LANGUAGE_INDEX 17
404 #define NGX_HTTP_V2_CONTENT_LENGTH_INDEX  28
405 #define NGX_HTTP_V2_CONTENT_TYPE_INDEX    31
406 #define NGX_HTTP_V2_DATE_INDEX            33
407 #define NGX_HTTP_V2_LAST_MODIFIED_INDEX   44
408 #define NGX_HTTP_V2_LOCATION_INDEX        46
409 #define NGX_HTTP_V2_SERVER_INDEX          54
410 #define NGX_HTTP_V2_USER_AGENT_INDEX      58
411 #define NGX_HTTP_V2_VARY_INDEX            59
412 
413 
414 u_char *ngx_http_v2_string_encode(u_char *dst, u_char *src, size_t len,
415     u_char *tmp, ngx_uint_t lower);
416 
417 
418 #endif /* _NGX_HTTP_V2_H_INCLUDED_ */
419