aboutsummaryrefslogtreecommitdiff
path: root/lib/http2.c
blob: a4baca9f120decec25a863e7618203a0243e9af2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
/***************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
 *
 * This software is licensed as described in the file COPYING, which
 * you should have received as part of this distribution. The terms
 * are also available at http://curl.haxx.se/docs/copyright.html.
 *
 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
 * copies of the Software, and permit persons to whom the Software is
 * furnished to do so, under the terms of the COPYING file.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ***************************************************************************/

#include "curl_setup.h"

#ifdef USE_NGHTTP2
#define _MPRINTF_REPLACE
#include <curl/mprintf.h>

#include <nghttp2/nghttp2.h>
#include "urldata.h"
#include "http2.h"
#include "http.h"
#include "sendf.h"
#include "curl_base64.h"
#include "curl_memory.h"
#include "rawstr.h"

/* include memdebug.h last */
#include "memdebug.h"

#if (NGHTTP2_VERSION_NUM < 0x000300)
#error too old nghttp2 version, upgrade!
#endif

/*
 * HTTP2 handler interface. This isn't added to the general list of protocols
 * but will be used at run-time when the protocol is dynamically switched from
 * HTTP to HTTP2.
 */
const struct Curl_handler Curl_handler_http2 = {
  "HTTP2",                              /* scheme */
  ZERO_NULL,                            /* setup_connection */
  ZERO_NULL,                            /* do_it */
  ZERO_NULL     ,                       /* done */
  ZERO_NULL,                            /* do_more */
  ZERO_NULL,                            /* connect_it */
  ZERO_NULL,                            /* connecting */
  ZERO_NULL,                            /* doing */
  ZERO_NULL,                            /* proto_getsock */
  ZERO_NULL,                            /* doing_getsock */
  ZERO_NULL,                            /* domore_getsock */
  ZERO_NULL,                            /* perform_getsock */
  ZERO_NULL,                            /* disconnect */
  ZERO_NULL,                            /* readwrite */
  PORT_HTTP,                            /* defport */
  CURLPROTO_HTTP,                       /* protocol */
  PROTOPT_NONE                          /* flags */
};


/*
 * Store nghttp2 version info in this buffer, Prefix with a space.  Return
 * total length written.
 */
int Curl_http2_ver(char *p, size_t len)
{
  nghttp2_info *h2 = nghttp2_version(0);
  return snprintf(p, len, " nghttp2/%s", h2->version_str);
}

/*
 * The implementation of nghttp2_send_callback type. Here we write |data| with
 * size |length| to the network and return the number of bytes actually
 * written. See the documentation of nghttp2_send_callback for the details.
 */
static ssize_t send_callback(nghttp2_session *h2,
                             const uint8_t *data, size_t length, int flags,
                             void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  struct http_conn *httpc = &conn->proto.httpc;
  ssize_t written;
  CURLcode rc;
  (void)h2;
  (void)flags;

  rc = 0;
  written = ((Curl_send*)httpc->send_underlying)(conn, FIRSTSOCKET,
                                                 data, length, &rc);

  if(rc == CURLE_AGAIN) {
    return NGHTTP2_ERR_WOULDBLOCK;
  }

  if(written == -1) {
    failf(conn->data, "Failed sending HTTP2 data");
    return NGHTTP2_ERR_CALLBACK_FAILURE;
  }

  if(!written)
    return NGHTTP2_ERR_WOULDBLOCK;

  return written;
}

static int on_frame_recv(nghttp2_session *session, const nghttp2_frame *frame,
                         void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  struct http_conn *c = &conn->proto.httpc;
  int rv;
  (void)session;
  (void)frame;
  infof(conn->data, "on_frame_recv() was called with header %x\n",
        frame->hd.type);
  switch(frame->hd.type) {
  case NGHTTP2_HEADERS:
    if(frame->headers.cat != NGHTTP2_HCAT_RESPONSE)
      break;
    c->bodystarted = TRUE;
    Curl_add_buffer(c->header_recvbuf, "\r\n", 2);
    c->nread_header_recvbuf = c->len < c->header_recvbuf->size_used ?
      c->len : c->header_recvbuf->size_used;

    memcpy(c->mem, c->header_recvbuf->buffer, c->nread_header_recvbuf);

    c->mem += c->nread_header_recvbuf;
    c->len -= c->nread_header_recvbuf;
    break;
  case NGHTTP2_PUSH_PROMISE:
    rv = nghttp2_submit_rst_stream(session, NGHTTP2_FLAG_NONE,
                                   frame->hd.stream_id, NGHTTP2_CANCEL);
    if(nghttp2_is_fatal(rv)) {
      return rv;
    }
    break;
  }
  return 0;
}

static int on_invalid_frame_recv(nghttp2_session *session,
                                 const nghttp2_frame *frame,
                                 nghttp2_error_code error_code, void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  (void)session;
  (void)frame;
  infof(conn->data, "on_invalid_frame_recv() was called, error_code = %d\n",
        error_code);
  return 0;
}

static int on_data_chunk_recv(nghttp2_session *session, uint8_t flags,
                              int32_t stream_id,
                              const uint8_t *data, size_t len, void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  struct http_conn *c = &conn->proto.httpc;
  size_t nread;
  (void)session;
  (void)flags;
  (void)data;
  infof(conn->data, "on_data_chunk_recv() "
        "len = %u, stream = %x\n", len, stream_id);

  if(stream_id != c->stream_id) {
    return 0;
  }

  nread = c->len < len ? c->len : len;
  memcpy(c->mem, data, nread);

  c->mem += nread;
  c->len -= nread;

  infof(conn->data, "%zu data written\n", nread);

  if(nread < len) {
    c->data = data + nread;
    c->datalen = len - nread;
    return NGHTTP2_ERR_PAUSE;
  }
  return 0;
}

static int before_frame_send(nghttp2_session *session,
                             const nghttp2_frame *frame,
                             void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  struct http_conn *c = &conn->proto.httpc;
  (void)session;
  (void)frame;
  infof(conn->data, "before_frame_send() was called\n");
  if(frame->hd.type == NGHTTP2_HEADERS &&
     frame->headers.cat == NGHTTP2_HCAT_REQUEST) {
    /* Get stream ID of our request */
    c->stream_id = frame->hd.stream_id;
  }
  return 0;
}
static int on_frame_send(nghttp2_session *session,
                         const nghttp2_frame *frame,
                         void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  (void)session;
  (void)frame;
  infof(conn->data, "on_frame_send() was called\n");
  return 0;
}
static int on_frame_not_send(nghttp2_session *session,
                             const nghttp2_frame *frame,
                             int lib_error_code, void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  (void)session;
  (void)frame;
  infof(conn->data, "on_frame_not_send() was called, lib_error_code = %d\n",
        lib_error_code);
  return 0;
}
static int on_stream_close(nghttp2_session *session, int32_t stream_id,
                           nghttp2_error_code error_code, void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  struct http_conn *c = &conn->proto.httpc;
  (void)session;
  (void)stream_id;
  infof(conn->data, "on_stream_close() was called, error_code = %d\n",
        error_code);

  if(stream_id != c->stream_id) {
    return 0;
  }

  c->closed = TRUE;

  return 0;
}

static int on_unknown_frame_recv(nghttp2_session *session,
                                 const uint8_t *head, size_t headlen,
                                 const uint8_t *payload, size_t payloadlen,
                                 void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  (void)session;
  (void)head;
  (void)headlen;
  (void)payload;
  (void)payloadlen;
  infof(conn->data, "on_unknown_frame_recv() was called\n");
  return 0;
}
static int on_begin_headers(nghttp2_session *session,
                            const nghttp2_frame *frame, void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  (void)session;
  (void)frame;
  infof(conn->data, "on_begin_headers() was called\n");
  return 0;
}

static const char STATUS[] = ":status";

/* frame->hd.type is either NGHTTP2_HEADERS or NGHTTP2_PUSH_PROMISE */
static int on_header(nghttp2_session *session, const nghttp2_frame *frame,
                      const uint8_t *name, size_t namelen,
                      const uint8_t *value, size_t valuelen,
                      void *userp)
{
  struct connectdata *conn = (struct connectdata *)userp;
  struct http_conn *c = &conn->proto.httpc;
  (void)session;
  (void)frame;

  if(frame->hd.stream_id != c->stream_id) {
    return 0;
  }

  if(namelen == sizeof(":status") - 1 &&
     memcmp(STATUS, name, namelen) == 0) {
    snprintf(c->header_recvbuf->buffer, 13, "HTTP/2.0 %s", value);
    c->header_recvbuf->buffer[12] = '\r';
    return 0;
  }
  else {
    /* convert to a HTTP1-style header */
    infof(conn->data, "got header\n");
    Curl_add_buffer(c->header_recvbuf, name, namelen);
    Curl_add_buffer(c->header_recvbuf, ":", 1);
    Curl_add_buffer(c->header_recvbuf, value, valuelen);
    Curl_add_buffer(c->header_recvbuf, "\r\n", 2);
  }

  return 0; /* 0 is successful */
}

/*
 * This is all callbacks nghttp2 calls
 */
static const nghttp2_session_callbacks callbacks = {
  send_callback,         /* nghttp2_send_callback */
  NULL,                  /* nghttp2_recv_callback */
  on_frame_recv,         /* nghttp2_on_frame_recv_callback */
  on_invalid_frame_recv, /* nghttp2_on_invalid_frame_recv_callback */
  on_data_chunk_recv,    /* nghttp2_on_data_chunk_recv_callback */
  before_frame_send,     /* nghttp2_before_frame_send_callback */
  on_frame_send,         /* nghttp2_on_frame_send_callback */
  on_frame_not_send,     /* nghttp2_on_frame_not_send_callback */
  on_stream_close,       /* nghttp2_on_stream_close_callback */
  on_unknown_frame_recv, /* nghttp2_on_unknown_frame_recv_callback */
  on_begin_headers,      /* nghttp2_on_begin_headers_callback */
  on_header              /* nghttp2_on_header_callback */
};

/*
 * The HTTP2 settings we send in the Upgrade request
 */
static nghttp2_settings_entry settings[] = {
  { NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, 100 },
  { NGHTTP2_SETTINGS_INITIAL_WINDOW_SIZE, NGHTTP2_INITIAL_WINDOW_SIZE },
};

#define H2_BUFSIZE 4096

/*
 * Initialize nghttp2 for a Curl connection
 */
CURLcode Curl_http2_init(struct connectdata *conn)
{
  if(!conn->proto.httpc.h2) {
    int rc;
    conn->proto.httpc.inbuf = malloc(H2_BUFSIZE);
    if(conn->proto.httpc.inbuf == NULL)
      return CURLE_OUT_OF_MEMORY;

    /* The nghttp2 session is not yet setup, do it */
    rc = nghttp2_session_client_new(&conn->proto.httpc.h2,
                                    &callbacks, conn);
    if(rc) {
      failf(conn->data, "Couldn't initialize nghttp2!");
      return CURLE_OUT_OF_MEMORY; /* most likely at least */
    }
  }
  return CURLE_OK;
}

/*
 * Send a request using http2
 */
CURLcode Curl_http2_send_request(struct connectdata *conn)
{
  (void)conn;
  return CURLE_OK;
}

/*
 * Append headers to ask for a HTTP1.1 to HTTP2 upgrade.
 */
CURLcode Curl_http2_request_upgrade(Curl_send_buffer *req,
                                    struct connectdata *conn)
{
  CURLcode result;
  ssize_t binlen;
  char *base64;
  size_t blen;
  struct SingleRequest *k = &conn->data->req;
  uint8_t *binsettings = conn->proto.httpc.binsettings;

  Curl_http2_init(conn);

  /* As long as we have a fixed set of settings, we don't have to dynamically
   * figure out the base64 strings since it'll always be the same. However,
   * the settings will likely not be fixed every time in the future.
   */

  /* this returns number of bytes it wrote */
  binlen = nghttp2_pack_settings_payload(binsettings, H2_BINSETTINGS_LEN,
                                         settings,
                                         sizeof(settings)/sizeof(settings[0]));
  if(!binlen) {
    failf(conn->data, "nghttp2 unexpectedly failed on pack_settings_payload");
    return CURLE_FAILED_INIT;
  }
  conn->proto.httpc.binlen = binlen;

  result = Curl_base64_encode(conn->data, (const char *)binsettings, binlen,
                              &base64, &blen);
  if(result)
    return result;

  result = Curl_add_bufferf(req,
                            "Connection: Upgrade, HTTP2-Settings\r\n"
                            "Upgrade: %s\r\n"
                            "HTTP2-Settings: %s\r\n",
                            NGHTTP2_PROTO_VERSION_ID, base64);
  free(base64);

  k->upgr101 = UPGR101_REQUESTED;

  return result;
}

/*
 * If the read would block (EWOULDBLOCK) we return -1. Otherwise we return
 * a regular CURLcode value.
 */
static ssize_t http2_recv(struct connectdata *conn, int sockindex,
                          char *mem, size_t len, CURLcode *err)
{
  CURLcode rc;
  ssize_t rv;
  ssize_t nread;
  struct http_conn *httpc = &conn->proto.httpc;

  (void)sockindex; /* we always do HTTP2 on sockindex 0 */

  if(httpc->bodystarted &&
     httpc->nread_header_recvbuf < httpc->header_recvbuf->size_used) {
    size_t left =
      httpc->header_recvbuf->size_used - httpc->nread_header_recvbuf;
    size_t ncopy = len < left ? len : left;
    memcpy(mem, httpc->header_recvbuf->buffer + httpc->nread_header_recvbuf,
           ncopy);
    httpc->nread_header_recvbuf += ncopy;
    return ncopy;
  }

  if(httpc->data) {
    nread = len < httpc->datalen ? len : httpc->datalen;
    memcpy(mem, httpc->data, nread);

    httpc->data += nread;
    httpc->datalen -= nread;

    infof(conn->data, "%zu data written\n", nread);
    if(httpc->datalen == 0) {
      httpc->data = NULL;
      httpc->datalen = 0;
    }
    return nread;
  }

  conn->proto.httpc.mem = mem;
  conn->proto.httpc.len = len;

  infof(conn->data, "http2_recv: %d bytes buffer\n",
        conn->proto.httpc.len);

  rc = 0;
  nread = ((Curl_recv*)httpc->recv_underlying)(conn, FIRSTSOCKET,
                                               httpc->inbuf, H2_BUFSIZE, &rc);

  if(rc == CURLE_AGAIN) {
    *err = rc;
    return -1;
  }

  if(nread == -1) {
    failf(conn->data, "Failed receiving HTTP2 data");
    *err = rc;
    return 0;
  }

  infof(conn->data, "nread=%zd\n", nread);
  rv = nghttp2_session_mem_recv(httpc->h2,
                                (const uint8_t *)httpc->inbuf, nread);

  if(nghttp2_is_fatal((int)rv)) {
    failf(conn->data, "nghttp2_session_mem_recv() returned %d:%s\n",
          rv, nghttp2_strerror((int)rv));
    *err = CURLE_RECV_ERROR;
    return 0;
  }
  infof(conn->data, "nghttp2_session_mem_recv() returns %zd\n", rv);
  /* Always send pending frames in nghttp2 session, because
     nghttp2_session_mem_recv() may queue new frame */
  rv = nghttp2_session_send(httpc->h2);
  if(rv != 0) {
    *err = CURLE_SEND_ERROR;
    return 0;
  }
  if(len != httpc->len) {
    return len - conn->proto.httpc.len;
  }
  /* If stream is closed, return 0 to signal the http routine to close
     the connection */
  if(httpc->closed) {
    return 0;
  }
  *err = CURLE_AGAIN;
  return -1;
}

#define MAKE_NV(k, v)                                           \
  { (uint8_t*)k, (uint8_t*)v, sizeof(k) - 1, sizeof(v) - 1 }

#define MAKE_NV2(k, v, vlen)                            \
  { (uint8_t*)k, (uint8_t*)v, sizeof(k) - 1, vlen }

/* return number of received (decrypted) bytes */
static ssize_t http2_send(struct connectdata *conn, int sockindex,
                          const void *mem, size_t len, CURLcode *err)
{
  /*
   * BIG TODO: Currently, we send request in this function, but this
   * function is also used to send request body. It would be nice to
   * add dedicated function for request.
   */
  int rv;
  struct http_conn *httpc = &conn->proto.httpc;
  nghttp2_nv *nva;
  size_t nheader;
  size_t i;
  char *hdbuf = (char*)mem;
  char *end;
  (void)sockindex;

  infof(conn->data, "http2_send len=%zu\n", len);

  /* Calculate number of headers contained in [mem, mem + len) */
  /* Here, we assume the curl http code generate *correct* HTTP header
     field block */
  nheader = 0;
  for(i = 0; i < len; ++i) {
    if(hdbuf[i] == 0x0a) {
      ++nheader;
    }
  }
  /* We counted additional 2 \n in the first and last line. We need 3
     new headers: :method, :path and :scheme. Therefore we need one
     more space. */
  nheader += 1;
  nva = malloc(sizeof(nghttp2_nv) * nheader);
  if(nva == NULL) {
    *err = CURLE_OUT_OF_MEMORY;
    return -1;
  }
  /* Extract :method, :path from request line */
  end = strchr(hdbuf, ' ');
  nva[0].name = (unsigned char *)":method";
  nva[0].namelen = (uint16_t)strlen((char *)nva[0].name);
  nva[0].value = (unsigned char *)hdbuf;
  nva[0].valuelen = (uint16_t)(end - hdbuf);

  hdbuf = end + 1;

  end = strchr(hdbuf, ' ');
  nva[1].name = (unsigned char *)":path";
  nva[1].namelen = (uint16_t)strlen((char *)nva[1].name);
  nva[1].value = (unsigned char *)hdbuf;
  nva[1].valuelen = (uint16_t)(end - hdbuf);

  nva[2].name = (unsigned char *)":scheme";
  nva[2].namelen = (uint16_t)strlen((char *)nva[2].name);
  if(conn->handler->flags & PROTOPT_SSL)
    nva[2].value = (unsigned char *)"https";
  else
    nva[2].value = (unsigned char *)"http";
  nva[2].valuelen = (uint16_t)strlen((char *)nva[2].value);

  hdbuf = strchr(hdbuf, 0x0a);
  ++hdbuf;

  for(i = 3; i < nheader; ++i) {
    end = strchr(hdbuf, ':');
    assert(end);
    if(end - hdbuf == 4 && Curl_raw_nequal("host", hdbuf, 4)) {
      nva[i].name = (unsigned char *)":authority";
      nva[i].namelen = (uint16_t)strlen((char *)nva[i].name);
    }
    else {
      nva[i].name = (unsigned char *)hdbuf;
      nva[i].namelen = (uint16_t)(end - hdbuf);
    }
    hdbuf = end + 1;
    for(; *hdbuf == ' '; ++hdbuf);
    end = strchr(hdbuf, 0x0d);
    assert(end);
    nva[i].value = (unsigned char *)hdbuf;
    nva[i].valuelen = (uint16_t)(end - hdbuf);

    hdbuf = end + 2;
  }

  rv = nghttp2_submit_request(httpc->h2, 0, nva, nheader, NULL, NULL);

  free(nva);

  if(rv != 0) {
    *err = CURLE_SEND_ERROR;
    return -1;
  }

  rv = nghttp2_session_send(httpc->h2);

  if(rv != 0) {
    *err = CURLE_SEND_ERROR;
    return -1;
  }

  /* TODO: Still whole HEADERS frame may have not been sent because of
     EAGAIN. But I don't know how to setup to call
     nghttp2_session_send() when socket becomes writable. */

  return len;
}

int Curl_http2_switched(struct connectdata *conn)
{
  int rv;
  CURLcode rc;
  struct http_conn *httpc = &conn->proto.httpc;
  /* we are switched! */
  /* Don't know this is needed here at this moment. Original
     handler->flags is still useful. */
  /* conn->handler = &Curl_handler_http2; */
  httpc->recv_underlying = (recving)conn->recv[FIRSTSOCKET];
  httpc->send_underlying = (sending)conn->send[FIRSTSOCKET];
  conn->recv[FIRSTSOCKET] = http2_recv;
  conn->send[FIRSTSOCKET] = http2_send;
  infof(conn->data, "We have switched to HTTP2\n");
  httpc->bodystarted = FALSE;
  httpc->closed = FALSE;
  httpc->header_recvbuf = Curl_add_buffer_init();
  httpc->nread_header_recvbuf = 0;
  httpc->data = NULL;
  httpc->datalen = 0;

  conn->httpversion = 20;

  /* Put place holder for status line */
  Curl_add_buffer(httpc->header_recvbuf, "HTTP/2.0 200\r\n", 14);

  /* TODO: May get CURLE_AGAIN */
  rv = (int) ((Curl_send*)httpc->send_underlying)
    (conn, FIRSTSOCKET,
     NGHTTP2_CLIENT_CONNECTION_HEADER,
     NGHTTP2_CLIENT_CONNECTION_HEADER_LEN,
     &rc);
  assert(rv == 24);
  if(conn->data->req.upgr101 == UPGR101_RECEIVED) {
    /* stream 1 is opened implicitly on upgrade */
    httpc->stream_id = 1;
    /* queue SETTINGS frame (again) */
    rv = nghttp2_session_upgrade(httpc->h2, httpc->binsettings,
                                 httpc->binlen, NULL);
    if(rv != 0) {
      failf(conn->data, "nghttp2_session_upgrade() failed: %s(%d)",
            nghttp2_strerror(rv), rv);
      return -1;
    }
  }
  else {
    /* stream ID is unknown at this point */
    httpc->stream_id = -1;
    rv = nghttp2_submit_settings(httpc->h2, NGHTTP2_FLAG_NONE, NULL, 0);
    if(rv != 0) {
      failf(conn->data, "nghttp2_submit_settings() failed: %s(%d)",
            nghttp2_strerror(rv), rv);
      return -1;
    }
  }
  return 0;
}

#endif