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1 /*
2  * nghttp2 - HTTP/2 C Library
3  *
4  * Copyright (c) 2012 Tatsuhiro Tsujikawa
5  *
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:
13  *
14  * The above copyright notice and this permission notice shall be
15  * included in all copies or substantial portions of the Software.
16  *
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.
24  */
25 #ifndef NGHTTP2_FRAME_H
26 #define NGHTTP2_FRAME_H
27 
28 #ifdef HAVE_CONFIG_H
29 #  include <config.h>
30 #endif /* HAVE_CONFIG_H */
31 
32 #include <nghttp2/nghttp2.h>
33 #include "nghttp2_hd.h"
34 #include "nghttp2_buf.h"
35 
36 #define NGHTTP2_STREAM_ID_MASK ((1u << 31) - 1)
37 #define NGHTTP2_PRI_GROUP_ID_MASK ((1u << 31) - 1)
38 #define NGHTTP2_PRIORITY_MASK ((1u << 31) - 1)
39 #define NGHTTP2_WINDOW_SIZE_INCREMENT_MASK ((1u << 31) - 1)
40 #define NGHTTP2_SETTINGS_ID_MASK ((1 << 24) - 1)
41 
42 /* The number of bytes of frame header. */
43 #define NGHTTP2_FRAME_HDLEN 9
44 
45 #define NGHTTP2_MAX_FRAME_SIZE_MAX ((1 << 24) - 1)
46 #define NGHTTP2_MAX_FRAME_SIZE_MIN (1 << 14)
47 
48 #define NGHTTP2_MAX_PAYLOADLEN 16384
49 /* The one frame buffer length for transmission.  We may use several of
50    them to support CONTINUATION.  To account for Pad Length field, we
51    allocate extra 1 byte, which saves extra large memcopying. */
52 #define NGHTTP2_FRAMEBUF_CHUNKLEN                                              \
53   (NGHTTP2_FRAME_HDLEN + 1 + NGHTTP2_MAX_PAYLOADLEN)
54 
55 /* The default length of DATA frame payload. */
56 #define NGHTTP2_DATA_PAYLOADLEN NGHTTP2_MAX_FRAME_SIZE_MIN
57 
58 /* Maximum headers block size to send, calculated using
59    nghttp2_hd_deflate_bound().  This is the default value, and can be
60    overridden by nghttp2_option_set_max_send_header_block_length(). */
61 #define NGHTTP2_MAX_HEADERSLEN 65536
62 
63 /* The number of bytes for each SETTINGS entry */
64 #define NGHTTP2_FRAME_SETTINGS_ENTRY_LENGTH 6
65 
66 /* Length of priority related fields in HEADERS/PRIORITY frames */
67 #define NGHTTP2_PRIORITY_SPECLEN 5
68 
69 /* Maximum length of padding in bytes. */
70 #define NGHTTP2_MAX_PADLEN 256
71 
72 /* Union of extension frame payload */
73 typedef union {
74   nghttp2_ext_altsvc altsvc;
75   nghttp2_ext_origin origin;
76   nghttp2_ext_priority_update priority_update;
77 } nghttp2_ext_frame_payload;
78 
79 void nghttp2_frame_pack_frame_hd(uint8_t *buf, const nghttp2_frame_hd *hd);
80 
81 void nghttp2_frame_unpack_frame_hd(nghttp2_frame_hd *hd, const uint8_t *buf);
82 
83 /**
84  * Initializes frame header |hd| with given parameters.  Reserved bit
85  * is set to 0.
86  */
87 void nghttp2_frame_hd_init(nghttp2_frame_hd *hd, size_t length, uint8_t type,
88                            uint8_t flags, int32_t stream_id);
89 
90 /**
91  * Returns the number of priority field depending on the |flags|.  If
92  * |flags| has neither NGHTTP2_FLAG_PRIORITY_GROUP nor
93  * NGHTTP2_FLAG_PRIORITY_DEPENDENCY set, return 0.
94  */
95 size_t nghttp2_frame_priority_len(uint8_t flags);
96 
97 /**
98  * Packs the |pri_spec| in |buf|.  This function assumes |buf| has
99  * enough space for serialization.
100  */
101 void nghttp2_frame_pack_priority_spec(uint8_t *buf,
102                                       const nghttp2_priority_spec *pri_spec);
103 
104 /**
105  * Unpacks the priority specification from payload |payload| of length
106  * |payloadlen| to |pri_spec|.  The |flags| is used to determine what
107  * kind of priority specification is in |payload|.  This function
108  * assumes the |payload| contains whole priority specification.
109  */
110 void nghttp2_frame_unpack_priority_spec(nghttp2_priority_spec *pri_spec,
111                                         const uint8_t *payload);
112 
113 /*
114  * Returns the offset from the HEADERS frame payload where the
115  * compressed header block starts. The frame payload does not include
116  * frame header.
117  */
118 size_t nghttp2_frame_headers_payload_nv_offset(nghttp2_headers *frame);
119 
120 /*
121  * Packs HEADERS frame |frame| in wire format and store it in |bufs|.
122  * This function expands |bufs| as necessary to store frame.
123  *
124  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
125  * before calling this function.
126  *
127  * frame->hd.length is assigned after length is determined during
128  * packing process.  CONTINUATION frames are also serialized in this
129  * function. This function does not handle padding.
130  *
131  * This function returns 0 if it succeeds, or returns one of the
132  * following negative error codes:
133  *
134  * NGHTTP2_ERR_HEADER_COMP
135  *     The deflate operation failed.
136  * NGHTTP2_ERR_NOMEM
137  *     Out of memory.
138  */
139 int nghttp2_frame_pack_headers(nghttp2_bufs *bufs, nghttp2_headers *frame,
140                                nghttp2_hd_deflater *deflater);
141 
142 /*
143  * Unpacks HEADERS frame byte sequence into |frame|.  This function
144  * only unapcks bytes that come before name/value header block and
145  * after possible Pad Length field.
146  */
147 void nghttp2_frame_unpack_headers_payload(nghttp2_headers *frame,
148                                           const uint8_t *payload);
149 
150 /*
151  * Packs PRIORITY frame |frame| in wire format and store it in
152  * |bufs|.
153  *
154  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
155  * before calling this function.
156  */
157 void nghttp2_frame_pack_priority(nghttp2_bufs *bufs, nghttp2_priority *frame);
158 
159 /*
160  * Unpacks PRIORITY wire format into |frame|.
161  */
162 void nghttp2_frame_unpack_priority_payload(nghttp2_priority *frame,
163                                            const uint8_t *payload);
164 
165 /*
166  * Packs RST_STREAM frame |frame| in wire frame format and store it in
167  * |bufs|.
168  *
169  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
170  * before calling this function.
171  */
172 void nghttp2_frame_pack_rst_stream(nghttp2_bufs *bufs,
173                                    nghttp2_rst_stream *frame);
174 
175 /*
176  * Unpacks RST_STREAM frame byte sequence into |frame|.
177  */
178 void nghttp2_frame_unpack_rst_stream_payload(nghttp2_rst_stream *frame,
179                                              const uint8_t *payload);
180 
181 /*
182  * Packs SETTINGS frame |frame| in wire format and store it in
183  * |bufs|.
184  *
185  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
186  * before calling this function.
187  *
188  * This function returns 0 if it succeeds, or returns one of the
189  * following negative error codes:
190  *
191  * NGHTTP2_ERR_FRAME_SIZE_ERROR
192  *     The length of the frame is too large.
193  */
194 int nghttp2_frame_pack_settings(nghttp2_bufs *bufs, nghttp2_settings *frame);
195 
196 /*
197  * Packs the |iv|, which includes |niv| entries, in the |buf|,
198  * assuming the |buf| has at least 8 * |niv| bytes.
199  *
200  * Returns the number of bytes written into the |buf|.
201  */
202 size_t nghttp2_frame_pack_settings_payload(uint8_t *buf,
203                                            const nghttp2_settings_entry *iv,
204                                            size_t niv);
205 
206 void nghttp2_frame_unpack_settings_entry(nghttp2_settings_entry *iv,
207                                          const uint8_t *payload);
208 
209 /*
210  * Initializes payload of frame->settings.  The |frame| takes
211  * ownership of |iv|.
212  */
213 void nghttp2_frame_unpack_settings_payload(nghttp2_settings *frame,
214                                            nghttp2_settings_entry *iv,
215                                            size_t niv);
216 
217 /*
218  * Unpacks SETTINGS payload into |*iv_ptr|. The number of entries are
219  * assigned to the |*niv_ptr|. This function allocates enough memory
220  * to store the result in |*iv_ptr|. The caller is responsible to free
221  * |*iv_ptr| after its use.
222  *
223  * This function returns 0 if it succeeds or one of the following
224  * negative error codes:
225  *
226  * NGHTTP2_ERR_NOMEM
227  *     Out of memory.
228  */
229 int nghttp2_frame_unpack_settings_payload2(nghttp2_settings_entry **iv_ptr,
230                                            size_t *niv_ptr,
231                                            const uint8_t *payload,
232                                            size_t payloadlen, nghttp2_mem *mem);
233 
234 /*
235  * Packs PUSH_PROMISE frame |frame| in wire format and store it in
236  * |bufs|.  This function expands |bufs| as necessary to store
237  * frame.
238  *
239  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
240  * before calling this function.
241  *
242  * frame->hd.length is assigned after length is determined during
243  * packing process.  CONTINUATION frames are also serialized in this
244  * function. This function does not handle padding.
245  *
246  * This function returns 0 if it succeeds, or returns one of the
247  * following negative error codes:
248  *
249  * NGHTTP2_ERR_HEADER_COMP
250  *     The deflate operation failed.
251  * NGHTTP2_ERR_NOMEM
252  *     Out of memory.
253  */
254 int nghttp2_frame_pack_push_promise(nghttp2_bufs *bufs,
255                                     nghttp2_push_promise *frame,
256                                     nghttp2_hd_deflater *deflater);
257 
258 /*
259  * Unpacks PUSH_PROMISE frame byte sequence into |frame|.  This
260  * function only unapcks bytes that come before name/value header
261  * block and after possible Pad Length field.
262  */
263 void nghttp2_frame_unpack_push_promise_payload(nghttp2_push_promise *frame,
264                                                const uint8_t *payload);
265 
266 /*
267  * Packs PING frame |frame| in wire format and store it in
268  * |bufs|.
269  *
270  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
271  * before calling this function.
272  */
273 void nghttp2_frame_pack_ping(nghttp2_bufs *bufs, nghttp2_ping *frame);
274 
275 /*
276  * Unpacks PING wire format into |frame|.
277  */
278 void nghttp2_frame_unpack_ping_payload(nghttp2_ping *frame,
279                                        const uint8_t *payload);
280 
281 /*
282  * Packs GOAWAY frame |frame| in wire format and store it in |bufs|.
283  * This function expands |bufs| as necessary to store frame.
284  *
285  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
286  * before calling this function.
287  *
288  * This function returns 0 if it succeeds or one of the following
289  * negative error codes:
290  *
291  * NGHTTP2_ERR_NOMEM
292  *     Out of memory.
293  * NGHTTP2_ERR_FRAME_SIZE_ERROR
294  *     The length of the frame is too large.
295  */
296 int nghttp2_frame_pack_goaway(nghttp2_bufs *bufs, nghttp2_goaway *frame);
297 
298 /*
299  * Unpacks GOAWAY wire format into |frame|.  The |payload| of length
300  * |payloadlen| contains first 8 bytes of payload.  The
301  * |var_gift_payload| of length |var_gift_payloadlen| contains
302  * remaining payload and its buffer is gifted to the function and then
303  * |frame|.  The |var_gift_payloadlen| must be freed by
304  * nghttp2_frame_goaway_free().
305  */
306 void nghttp2_frame_unpack_goaway_payload(nghttp2_goaway *frame,
307                                          const uint8_t *payload,
308                                          uint8_t *var_gift_payload,
309                                          size_t var_gift_payloadlen);
310 
311 /*
312  * Unpacks GOAWAY wire format into |frame|.  This function only exists
313  * for unit test.  After allocating buffer for debug data, this
314  * function internally calls nghttp2_frame_unpack_goaway_payload().
315  *
316  * This function returns 0 if it succeeds, or one of the following
317  * negative error codes:
318  *
319  * NGHTTP2_ERR_NOMEM
320  *     Out of memory.
321  */
322 int nghttp2_frame_unpack_goaway_payload2(nghttp2_goaway *frame,
323                                          const uint8_t *payload,
324                                          size_t payloadlen, nghttp2_mem *mem);
325 
326 /*
327  * Packs WINDOW_UPDATE frame |frame| in wire frame format and store it
328  * in |bufs|.
329  *
330  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
331  * before calling this function.
332  */
333 void nghttp2_frame_pack_window_update(nghttp2_bufs *bufs,
334                                       nghttp2_window_update *frame);
335 
336 /*
337  * Unpacks WINDOW_UPDATE frame byte sequence into |frame|.
338  */
339 void nghttp2_frame_unpack_window_update_payload(nghttp2_window_update *frame,
340                                                 const uint8_t *payload);
341 
342 /*
343  * Packs ALTSVC frame |frame| in wire frame format and store it in
344  * |bufs|.
345  *
346  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
347  * before calling this function.
348  */
349 void nghttp2_frame_pack_altsvc(nghttp2_bufs *bufs, nghttp2_extension *ext);
350 
351 /*
352  * Unpacks ALTSVC wire format into |frame|.  The |payload| of
353  * |payloadlen| bytes contains frame payload.  This function assumes
354  * that frame->payload points to the nghttp2_ext_altsvc object.
355  */
356 void nghttp2_frame_unpack_altsvc_payload(nghttp2_extension *frame,
357                                          size_t origin_len, uint8_t *payload,
358                                          size_t payloadlen);
359 
360 /*
361  * Unpacks ALTSVC wire format into |frame|.  This function only exists
362  * for unit test.  After allocating buffer for fields, this function
363  * internally calls nghttp2_frame_unpack_altsvc_payload().
364  *
365  * This function returns 0 if it succeeds, or one of the following
366  * negative error codes:
367  *
368  * NGHTTP2_ERR_NOMEM
369  *     Out of memory.
370  * NGHTTP2_ERR_FRAME_SIZE_ERROR
371  *     The payload is too small.
372  */
373 int nghttp2_frame_unpack_altsvc_payload2(nghttp2_extension *frame,
374                                          const uint8_t *payload,
375                                          size_t payloadlen, nghttp2_mem *mem);
376 
377 /*
378  * Packs ORIGIN frame |frame| in wire frame format and store it in
379  * |bufs|.
380  *
381  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
382  * before calling this function.
383  *
384  * This function returns 0 if it succeeds, or one of the following
385  * negative error codes:
386  *
387  * NGHTTP2_ERR_FRAME_SIZE_ERROR
388  *     The length of the frame is too large.
389  */
390 int nghttp2_frame_pack_origin(nghttp2_bufs *bufs, nghttp2_extension *ext);
391 
392 /*
393  * Unpacks ORIGIN wire format into |frame|.  The |payload| of length
394  * |payloadlen| contains the frame payload.
395  *
396  * This function returns 0 if it succeeds, or one of the following
397  * negative error codes:
398  *
399  * NGHTTP2_ERR_NOMEM
400  *     Out of memory.
401  * NGHTTP2_ERR_FRAME_SIZE_ERROR
402  *     The payload is too small.
403  */
404 int nghttp2_frame_unpack_origin_payload(nghttp2_extension *frame,
405                                         const uint8_t *payload,
406                                         size_t payloadlen, nghttp2_mem *mem);
407 
408 /*
409  * Packs PRIORITY_UPDATE frame |frame| in wire frame format and store
410  * it in |bufs|.
411  *
412  * The caller must make sure that nghttp2_bufs_reset(bufs) is called
413  * before calling this function.
414  */
415 void nghttp2_frame_pack_priority_update(nghttp2_bufs *bufs,
416                                         nghttp2_extension *ext);
417 
418 /*
419  * Unpacks PRIORITY_UPDATE wire format into |frame|.  The |payload| of
420  * |payloadlen| bytes contains frame payload.  This function assumes
421  * that frame->payload points to the nghttp2_ext_priority_update
422  * object.
423  */
424 void nghttp2_frame_unpack_priority_update_payload(nghttp2_extension *frame,
425                                                   uint8_t *payload,
426                                                   size_t payloadlen);
427 
428 /*
429  * Initializes HEADERS frame |frame| with given values.  |frame| takes
430  * ownership of |nva|, so caller must not free it. If |stream_id| is
431  * not assigned yet, it must be -1.
432  */
433 void nghttp2_frame_headers_init(nghttp2_headers *frame, uint8_t flags,
434                                 int32_t stream_id, nghttp2_headers_category cat,
435                                 const nghttp2_priority_spec *pri_spec,
436                                 nghttp2_nv *nva, size_t nvlen);
437 
438 void nghttp2_frame_headers_free(nghttp2_headers *frame, nghttp2_mem *mem);
439 
440 void nghttp2_frame_priority_init(nghttp2_priority *frame, int32_t stream_id,
441                                  const nghttp2_priority_spec *pri_spec);
442 
443 void nghttp2_frame_priority_free(nghttp2_priority *frame);
444 
445 void nghttp2_frame_rst_stream_init(nghttp2_rst_stream *frame, int32_t stream_id,
446                                    uint32_t error_code);
447 
448 void nghttp2_frame_rst_stream_free(nghttp2_rst_stream *frame);
449 
450 /*
451  * Initializes PUSH_PROMISE frame |frame| with given values.  |frame|
452  * takes ownership of |nva|, so caller must not free it.
453  */
454 void nghttp2_frame_push_promise_init(nghttp2_push_promise *frame, uint8_t flags,
455                                      int32_t stream_id,
456                                      int32_t promised_stream_id,
457                                      nghttp2_nv *nva, size_t nvlen);
458 
459 void nghttp2_frame_push_promise_free(nghttp2_push_promise *frame,
460                                      nghttp2_mem *mem);
461 
462 /*
463  * Initializes SETTINGS frame |frame| with given values. |frame| takes
464  * ownership of |iv|, so caller must not free it. The |flags| are
465  * bitwise-OR of one or more of nghttp2_settings_flag.
466  */
467 void nghttp2_frame_settings_init(nghttp2_settings *frame, uint8_t flags,
468                                  nghttp2_settings_entry *iv, size_t niv);
469 
470 void nghttp2_frame_settings_free(nghttp2_settings *frame, nghttp2_mem *mem);
471 
472 /*
473  * Initializes PING frame |frame| with given values. If the
474  * |opqeue_data| is not NULL, it must point to 8 bytes memory region
475  * of data. The data pointed by |opaque_data| is copied. It can be
476  * NULL. In this case, 8 bytes NULL is used.
477  */
478 void nghttp2_frame_ping_init(nghttp2_ping *frame, uint8_t flags,
479                              const uint8_t *opque_data);
480 
481 void nghttp2_frame_ping_free(nghttp2_ping *frame);
482 
483 /*
484  * Initializes GOAWAY frame |frame| with given values. On success,
485  * this function takes ownership of |opaque_data|, so caller must not
486  * free it. If the |opaque_data_len| is 0, opaque_data could be NULL.
487  */
488 void nghttp2_frame_goaway_init(nghttp2_goaway *frame, int32_t last_stream_id,
489                                uint32_t error_code, uint8_t *opaque_data,
490                                size_t opaque_data_len);
491 
492 void nghttp2_frame_goaway_free(nghttp2_goaway *frame, nghttp2_mem *mem);
493 
494 void nghttp2_frame_window_update_init(nghttp2_window_update *frame,
495                                       uint8_t flags, int32_t stream_id,
496                                       int32_t window_size_increment);
497 
498 void nghttp2_frame_window_update_free(nghttp2_window_update *frame);
499 
500 void nghttp2_frame_extension_init(nghttp2_extension *frame, uint8_t type,
501                                   uint8_t flags, int32_t stream_id,
502                                   void *payload);
503 
504 void nghttp2_frame_extension_free(nghttp2_extension *frame);
505 
506 /*
507  * Initializes ALTSVC frame |frame| with given values.  This function
508  * assumes that frame->payload points to nghttp2_ext_altsvc object.
509  * Also |origin| and |field_value| are allocated in single buffer,
510  * starting |origin|.  On success, this function takes ownership of
511  * |origin|, so caller must not free it.
512  */
513 void nghttp2_frame_altsvc_init(nghttp2_extension *frame, int32_t stream_id,
514                                uint8_t *origin, size_t origin_len,
515                                uint8_t *field_value, size_t field_value_len);
516 
517 /*
518  * Frees up resources under |frame|.  This function does not free
519  * nghttp2_ext_altsvc object pointed by frame->payload.  This function
520  * only frees origin pointed by nghttp2_ext_altsvc.origin.  Therefore,
521  * other fields must be allocated in the same buffer with origin.
522  */
523 void nghttp2_frame_altsvc_free(nghttp2_extension *frame, nghttp2_mem *mem);
524 
525 /*
526  * Initializes ORIGIN frame |frame| with given values.  This function
527  * assumes that frame->payload points to nghttp2_ext_origin object.
528  * Also |ov| and the memory pointed by the field of its elements are
529  * allocated in single buffer, starting with |ov|.  On success, this
530  * function takes ownership of |ov|, so caller must not free it.
531  */
532 void nghttp2_frame_origin_init(nghttp2_extension *frame,
533                                nghttp2_origin_entry *ov, size_t nov);
534 
535 /*
536  * Frees up resources under |frame|.  This function does not free
537  * nghttp2_ext_origin object pointed by frame->payload.  This function
538  * only frees nghttp2_ext_origin.ov.  Therefore, other fields must be
539  * allocated in the same buffer with ov.
540  */
541 void nghttp2_frame_origin_free(nghttp2_extension *frame, nghttp2_mem *mem);
542 
543 /*
544  * Initializes PRIORITY_UPDATE frame |frame| with given values.  This
545  * function assumes that frame->payload points to
546  * nghttp2_ext_priority_update object.  On success, this function
547  * takes ownership of |field_value|, so caller must not free it.
548  */
549 void nghttp2_frame_priority_update_init(nghttp2_extension *frame,
550                                         int32_t stream_id, uint8_t *field_value,
551                                         size_t field_value_len);
552 
553 /*
554  * Frees up resources under |frame|.  This function does not free
555  * nghttp2_ext_priority_update object pointed by frame->payload.  This
556  * function only frees field_value pointed by
557  * nghttp2_ext_priority_update.field_value.
558  */
559 void nghttp2_frame_priority_update_free(nghttp2_extension *frame,
560                                         nghttp2_mem *mem);
561 
562 /*
563  * Returns the number of padding bytes after payload.  The total
564  * padding length is given in the |padlen|.  The returned value does
565  * not include the Pad Length field.  If |padlen| is 0, this function
566  * returns 0, regardless of frame->hd.flags.
567  */
568 size_t nghttp2_frame_trail_padlen(nghttp2_frame *frame, size_t padlen);
569 
570 void nghttp2_frame_data_init(nghttp2_data *frame, uint8_t flags,
571                              int32_t stream_id);
572 
573 void nghttp2_frame_data_free(nghttp2_data *frame);
574 
575 /*
576  * Makes copy of |iv| and return the copy. The |niv| is the number of
577  * entries in |iv|. This function returns the pointer to the copy if
578  * it succeeds, or NULL.
579  */
580 nghttp2_settings_entry *nghttp2_frame_iv_copy(const nghttp2_settings_entry *iv,
581                                               size_t niv, nghttp2_mem *mem);
582 
583 /*
584  * Sorts the |nva| in ascending order of name and value. If names are
585  * equivalent, sort them by value.
586  */
587 void nghttp2_nv_array_sort(nghttp2_nv *nva, size_t nvlen);
588 
589 /*
590  * Copies name/value pairs from |nva|, which contains |nvlen| pairs,
591  * to |*nva_ptr|, which is dynamically allocated so that all items can
592  * be stored.  The resultant name and value in nghttp2_nv are
593  * guaranteed to be NULL-terminated even if the input is not
594  * null-terminated.
595  *
596  * The |*nva_ptr| must be freed using nghttp2_nv_array_del().
597  *
598  * This function returns 0 if it succeeds or one of the following
599  * negative error codes:
600  *
601  * NGHTTP2_ERR_NOMEM
602  *     Out of memory.
603  */
604 int nghttp2_nv_array_copy(nghttp2_nv **nva_ptr, const nghttp2_nv *nva,
605                           size_t nvlen, nghttp2_mem *mem);
606 
607 /*
608  * Returns nonzero if the name/value pair |a| equals to |b|. The name
609  * is compared in case-sensitive, because we ensure that this function
610  * is called after the name is lower-cased.
611  */
612 int nghttp2_nv_equal(const nghttp2_nv *a, const nghttp2_nv *b);
613 
614 /*
615  * Frees |nva|.
616  */
617 void nghttp2_nv_array_del(nghttp2_nv *nva, nghttp2_mem *mem);
618 
619 /*
620  * Checks that the |iv|, which includes |niv| entries, does not have
621  * invalid values.
622  *
623  * This function returns nonzero if it succeeds, or 0.
624  */
625 int nghttp2_iv_check(const nghttp2_settings_entry *iv, size_t niv);
626 
627 /*
628  * Sets Pad Length field and flags and adjusts frame header position
629  * of each buffers in |bufs|.  The number of padding is given in the
630  * |padlen| including Pad Length field.  The |hd| is the frame header
631  * for the serialized data.  This function fills zeros padding region
632  * unless framehd_only is nonzero.
633  */
634 void nghttp2_frame_add_pad(nghttp2_bufs *bufs, nghttp2_frame_hd *hd,
635                            size_t padlen, int framehd_only);
636 
637 #endif /* NGHTTP2_FRAME_H */
638