1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2014, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23#include "curl_setup.h"
24
25#include "strtoofft.h"
26#include "strequal.h"
27#include "rawstr.h"
28
29#ifdef HAVE_NETINET_IN_H
30#include <netinet/in.h>
31#endif
32#ifdef HAVE_NETDB_H
33#include <netdb.h>
34#endif
35#ifdef HAVE_ARPA_INET_H
36#include <arpa/inet.h>
37#endif
38#ifdef HAVE_NET_IF_H
39#include <net/if.h>
40#endif
41#ifdef HAVE_SYS_IOCTL_H
42#include <sys/ioctl.h>
43#endif
44#ifdef HAVE_SIGNAL_H
45#include <signal.h>
46#endif
47
48#ifdef HAVE_SYS_PARAM_H
49#include <sys/param.h>
50#endif
51
52#ifdef HAVE_SYS_SELECT_H
53#include <sys/select.h>
54#endif
55
56#ifndef HAVE_SOCKET
57#error "We can't compile without socket() support!"
58#endif
59
60#include "urldata.h"
61#include <curl/curl.h>
62#include "netrc.h"
63
64#include "content_encoding.h"
65#include "hostip.h"
66#include "transfer.h"
67#include "sendf.h"
68#include "speedcheck.h"
69#include "progress.h"
70#include "http.h"
71#include "url.h"
72#include "getinfo.h"
73#include "vtls/vtls.h"
74#include "http_digest.h"
75#include "curl_ntlm.h"
76#include "http_negotiate.h"
77#include "share.h"
78#include "curl_memory.h"
79#include "select.h"
80#include "multiif.h"
81#include "connect.h"
82#include "non-ascii.h"
83
84#define _MPRINTF_REPLACE /* use our functions only */
85#include <curl/mprintf.h>
86
87/* The last #include file should be: */
88#include "memdebug.h"
89
90/*
91 * This function will call the read callback to fill our buffer with data
92 * to upload.
93 */
94CURLcode Curl_fillreadbuffer(struct connectdata *conn, int bytes, int *nreadp)
95{
96  struct SessionHandle *data = conn->data;
97  size_t buffersize = (size_t)bytes;
98  int nread;
99#ifdef CURL_DOES_CONVERSIONS
100  bool sending_http_headers = FALSE;
101
102  if(conn->handler->protocol&(PROTO_FAMILY_HTTP|CURLPROTO_RTSP)) {
103    const struct HTTP *http = data->req.protop;
104
105    if(http->sending == HTTPSEND_REQUEST)
106      /* We're sending the HTTP request headers, not the data.
107         Remember that so we don't re-translate them into garbage. */
108      sending_http_headers = TRUE;
109  }
110#endif
111
112  if(data->req.upload_chunky) {
113    /* if chunked Transfer-Encoding */
114    buffersize -= (8 + 2 + 2);   /* 32bit hex + CRLF + CRLF */
115    data->req.upload_fromhere += (8 + 2); /* 32bit hex + CRLF */
116  }
117
118  /* this function returns a size_t, so we typecast to int to prevent warnings
119     with picky compilers */
120  nread = (int)conn->fread_func(data->req.upload_fromhere, 1,
121                                buffersize, conn->fread_in);
122
123  if(nread == CURL_READFUNC_ABORT) {
124    failf(data, "operation aborted by callback");
125    *nreadp = 0;
126    return CURLE_ABORTED_BY_CALLBACK;
127  }
128  else if(nread == CURL_READFUNC_PAUSE) {
129
130    if(conn->handler->flags & PROTOPT_NONETWORK) {
131      /* protocols that work without network cannot be paused. This is
132         actually only FILE:// just now, and it can't pause since the transfer
133         isn't done using the "normal" procedure. */
134      failf(data, "Read callback asked for PAUSE when not supported!");
135      return CURLE_READ_ERROR;
136    }
137    else {
138      struct SingleRequest *k = &data->req;
139      /* CURL_READFUNC_PAUSE pauses read callbacks that feed socket writes */
140      k->keepon |= KEEP_SEND_PAUSE; /* mark socket send as paused */
141      if(data->req.upload_chunky) {
142        /* Back out the preallocation done above */
143        data->req.upload_fromhere -= (8 + 2);
144      }
145      *nreadp = 0;
146    }
147    return CURLE_OK; /* nothing was read */
148  }
149  else if((size_t)nread > buffersize) {
150    /* the read function returned a too large value */
151    *nreadp = 0;
152    failf(data, "read function returned funny value");
153    return CURLE_READ_ERROR;
154  }
155
156  if(!data->req.forbidchunk && data->req.upload_chunky) {
157    /* if chunked Transfer-Encoding
158     *    build chunk:
159     *
160     *        <HEX SIZE> CRLF
161     *        <DATA> CRLF
162     */
163    /* On non-ASCII platforms the <DATA> may or may not be
164       translated based on set.prefer_ascii while the protocol
165       portion must always be translated to the network encoding.
166       To further complicate matters, line end conversion might be
167       done later on, so we need to prevent CRLFs from becoming
168       CRCRLFs if that's the case.  To do this we use bare LFs
169       here, knowing they'll become CRLFs later on.
170     */
171
172    char hexbuffer[11];
173    const char *endofline_native;
174    const char *endofline_network;
175    int hexlen;
176
177    if(
178#ifdef CURL_DO_LINEEND_CONV
179       (data->set.prefer_ascii) ||
180#endif
181       (data->set.crlf)) {
182      /* \n will become \r\n later on */
183      endofline_native  = "\n";
184      endofline_network = "\x0a";
185    }
186    else {
187      endofline_native  = "\r\n";
188      endofline_network = "\x0d\x0a";
189    }
190    hexlen = snprintf(hexbuffer, sizeof(hexbuffer),
191                      "%x%s", nread, endofline_native);
192
193    /* move buffer pointer */
194    data->req.upload_fromhere -= hexlen;
195    nread += hexlen;
196
197    /* copy the prefix to the buffer, leaving out the NUL */
198    memcpy(data->req.upload_fromhere, hexbuffer, hexlen);
199
200    /* always append ASCII CRLF to the data */
201    memcpy(data->req.upload_fromhere + nread,
202           endofline_network,
203           strlen(endofline_network));
204
205#ifdef CURL_DOES_CONVERSIONS
206    CURLcode res;
207    int length;
208    if(data->set.prefer_ascii) {
209      /* translate the protocol and data */
210      length = nread;
211    }
212    else {
213      /* just translate the protocol portion */
214      length = strlen(hexbuffer);
215    }
216    res = Curl_convert_to_network(data, data->req.upload_fromhere, length);
217    /* Curl_convert_to_network calls failf if unsuccessful */
218    if(res)
219      return(res);
220#endif /* CURL_DOES_CONVERSIONS */
221
222    if((nread - hexlen) == 0)
223      /* mark this as done once this chunk is transferred */
224      data->req.upload_done = TRUE;
225
226    nread+=(int)strlen(endofline_native); /* for the added end of line */
227  }
228#ifdef CURL_DOES_CONVERSIONS
229  else if((data->set.prefer_ascii) && (!sending_http_headers)) {
230    CURLcode res;
231    res = Curl_convert_to_network(data, data->req.upload_fromhere, nread);
232    /* Curl_convert_to_network calls failf if unsuccessful */
233    if(res != CURLE_OK)
234      return(res);
235  }
236#endif /* CURL_DOES_CONVERSIONS */
237
238  *nreadp = nread;
239
240  return CURLE_OK;
241}
242
243
244/*
245 * Curl_readrewind() rewinds the read stream. This is typically used for HTTP
246 * POST/PUT with multi-pass authentication when a sending was denied and a
247 * resend is necessary.
248 */
249CURLcode Curl_readrewind(struct connectdata *conn)
250{
251  struct SessionHandle *data = conn->data;
252
253  conn->bits.rewindaftersend = FALSE; /* we rewind now */
254
255  /* explicitly switch off sending data on this connection now since we are
256     about to restart a new transfer and thus we want to avoid inadvertently
257     sending more data on the existing connection until the next transfer
258     starts */
259  data->req.keepon &= ~KEEP_SEND;
260
261  /* We have sent away data. If not using CURLOPT_POSTFIELDS or
262     CURLOPT_HTTPPOST, call app to rewind
263  */
264  if(data->set.postfields ||
265     (data->set.httpreq == HTTPREQ_POST_FORM))
266    ; /* do nothing */
267  else {
268    if(data->set.seek_func) {
269      int err;
270
271      err = (data->set.seek_func)(data->set.seek_client, 0, SEEK_SET);
272      if(err) {
273        failf(data, "seek callback returned error %d", (int)err);
274        return CURLE_SEND_FAIL_REWIND;
275      }
276    }
277    else if(data->set.ioctl_func) {
278      curlioerr err;
279
280      err = (data->set.ioctl_func)(data, CURLIOCMD_RESTARTREAD,
281                                   data->set.ioctl_client);
282      infof(data, "the ioctl callback returned %d\n", (int)err);
283
284      if(err) {
285        /* FIXME: convert to a human readable error message */
286        failf(data, "ioctl callback returned error %d", (int)err);
287        return CURLE_SEND_FAIL_REWIND;
288      }
289    }
290    else {
291      /* If no CURLOPT_READFUNCTION is used, we know that we operate on a
292         given FILE * stream and we can actually attempt to rewind that
293         ourselves with fseek() */
294      if(data->set.fread_func == (curl_read_callback)fread) {
295        if(-1 != fseek(data->set.in, 0, SEEK_SET))
296          /* successful rewind */
297          return CURLE_OK;
298      }
299
300      /* no callback set or failure above, makes us fail at once */
301      failf(data, "necessary data rewind wasn't possible");
302      return CURLE_SEND_FAIL_REWIND;
303    }
304  }
305  return CURLE_OK;
306}
307
308static int data_pending(const struct connectdata *conn)
309{
310  /* in the case of libssh2, we can never be really sure that we have emptied
311     its internal buffers so we MUST always try until we get EAGAIN back */
312  return conn->handler->protocol&(CURLPROTO_SCP|CURLPROTO_SFTP) ||
313#if defined(USE_NGHTTP2)
314    Curl_ssl_data_pending(conn, FIRSTSOCKET) ||
315    /* For HTTP/2, we may read up everything including responde body
316       with header fields in Curl_http_readwrite_headers. If no
317       content-length is provided, curl waits for the connection
318       close, which we emulate it using conn->proto.httpc.closed =
319       TRUE. The thing is if we read everything, then http2_recv won't
320       be called and we cannot signal the HTTP/2 stream has closed. As
321       a workaround, we return nonzero here to call http2_recv. */
322    ((conn->handler->protocol&PROTO_FAMILY_HTTP) && conn->httpversion == 20 &&
323     conn->proto.httpc.closed);
324#else
325    Curl_ssl_data_pending(conn, FIRSTSOCKET);
326#endif
327}
328
329static void read_rewind(struct connectdata *conn,
330                        size_t thismuch)
331{
332  DEBUGASSERT(conn->read_pos >= thismuch);
333
334  conn->read_pos -= thismuch;
335  conn->bits.stream_was_rewound = TRUE;
336
337#ifdef DEBUGBUILD
338  {
339    char buf[512 + 1];
340    size_t show;
341
342    show = CURLMIN(conn->buf_len - conn->read_pos, sizeof(buf)-1);
343    if(conn->master_buffer) {
344      memcpy(buf, conn->master_buffer + conn->read_pos, show);
345      buf[show] = '\0';
346    }
347    else {
348      buf[0] = '\0';
349    }
350
351    DEBUGF(infof(conn->data,
352                 "Buffer after stream rewind (read_pos = %zu): [%s]\n",
353                 conn->read_pos, buf));
354  }
355#endif
356}
357
358/*
359 * Check to see if CURLOPT_TIMECONDITION was met by comparing the time of the
360 * remote document with the time provided by CURLOPT_TIMEVAL
361 */
362bool Curl_meets_timecondition(struct SessionHandle *data, time_t timeofdoc)
363{
364  if((timeofdoc == 0) || (data->set.timevalue == 0))
365    return TRUE;
366
367  switch(data->set.timecondition) {
368  case CURL_TIMECOND_IFMODSINCE:
369  default:
370    if(timeofdoc <= data->set.timevalue) {
371      infof(data,
372            "The requested document is not new enough\n");
373      data->info.timecond = TRUE;
374      return FALSE;
375    }
376    break;
377  case CURL_TIMECOND_IFUNMODSINCE:
378    if(timeofdoc >= data->set.timevalue) {
379      infof(data,
380            "The requested document is not old enough\n");
381      data->info.timecond = TRUE;
382      return FALSE;
383    }
384    break;
385  }
386
387  return TRUE;
388}
389
390/*
391 * Go ahead and do a read if we have a readable socket or if
392 * the stream was rewound (in which case we have data in a
393 * buffer)
394 */
395static CURLcode readwrite_data(struct SessionHandle *data,
396                               struct connectdata *conn,
397                               struct SingleRequest *k,
398                               int *didwhat, bool *done)
399{
400  CURLcode result = CURLE_OK;
401  ssize_t nread; /* number of bytes read */
402  size_t excess = 0; /* excess bytes read */
403  bool is_empty_data = FALSE;
404  bool readmore = FALSE; /* used by RTP to signal for more data */
405
406  *done = FALSE;
407
408  /* This is where we loop until we have read everything there is to
409     read or we get a CURLE_AGAIN */
410  do {
411    size_t buffersize = data->set.buffer_size?
412      data->set.buffer_size : BUFSIZE;
413    size_t bytestoread = buffersize;
414
415    if(k->size != -1 && !k->header) {
416      /* make sure we don't read "too much" if we can help it since we
417         might be pipelining and then someone else might want to read what
418         follows! */
419      curl_off_t totalleft = k->size - k->bytecount;
420      if(totalleft < (curl_off_t)bytestoread)
421        bytestoread = (size_t)totalleft;
422    }
423
424    if(bytestoread) {
425      /* receive data from the network! */
426      result = Curl_read(conn, conn->sockfd, k->buf, bytestoread, &nread);
427
428      /* read would've blocked */
429      if(CURLE_AGAIN == result)
430        break; /* get out of loop */
431
432      if(result>0)
433        return result;
434    }
435    else {
436      /* read nothing but since we wanted nothing we consider this an OK
437         situation to proceed from */
438      nread = 0;
439    }
440
441    if((k->bytecount == 0) && (k->writebytecount == 0)) {
442      Curl_pgrsTime(data, TIMER_STARTTRANSFER);
443      if(k->exp100 > EXP100_SEND_DATA)
444        /* set time stamp to compare with when waiting for the 100 */
445        k->start100 = Curl_tvnow();
446    }
447
448    *didwhat |= KEEP_RECV;
449    /* indicates data of zero size, i.e. empty file */
450    is_empty_data = ((nread == 0) && (k->bodywrites == 0)) ? TRUE : FALSE;
451
452    /* NUL terminate, allowing string ops to be used */
453    if(0 < nread || is_empty_data) {
454      k->buf[nread] = 0;
455    }
456    else if(0 >= nread) {
457      /* if we receive 0 or less here, the server closed the connection
458         and we bail out from this! */
459      DEBUGF(infof(data, "nread <= 0, server closed connection, bailing\n"));
460      k->keepon &= ~KEEP_RECV;
461      break;
462    }
463
464    /* Default buffer to use when we write the buffer, it may be changed
465       in the flow below before the actual storing is done. */
466    k->str = k->buf;
467
468    if(conn->handler->readwrite) {
469      result = conn->handler->readwrite(data, conn, &nread, &readmore);
470      if(result)
471        return result;
472      if(readmore)
473        break;
474    }
475
476#ifndef CURL_DISABLE_HTTP
477    /* Since this is a two-state thing, we check if we are parsing
478       headers at the moment or not. */
479    if(k->header) {
480      /* we are in parse-the-header-mode */
481      bool stop_reading = FALSE;
482      result = Curl_http_readwrite_headers(data, conn, &nread, &stop_reading);
483      if(result)
484        return result;
485
486      if(conn->handler->readwrite &&
487         (k->maxdownload <= 0 && nread > 0)) {
488        result = conn->handler->readwrite(data, conn, &nread, &readmore);
489        if(result)
490          return result;
491        if(readmore)
492          break;
493      }
494
495      if(stop_reading) {
496        /* We've stopped dealing with input, get out of the do-while loop */
497
498        if(nread > 0) {
499          if(Curl_multi_pipeline_enabled(conn->data->multi)) {
500            infof(data,
501                  "Rewinding stream by : %zd"
502                  " bytes on url %s (zero-length body)\n",
503                  nread, data->state.path);
504            read_rewind(conn, (size_t)nread);
505          }
506          else {
507            infof(data,
508                  "Excess found in a non pipelined read:"
509                  " excess = %zd"
510                  " url = %s (zero-length body)\n",
511                  nread, data->state.path);
512          }
513        }
514
515        break;
516      }
517    }
518#endif /* CURL_DISABLE_HTTP */
519
520
521    /* This is not an 'else if' since it may be a rest from the header
522       parsing, where the beginning of the buffer is headers and the end
523       is non-headers. */
524    if(k->str && !k->header && (nread > 0 || is_empty_data)) {
525
526#ifndef CURL_DISABLE_HTTP
527      if(0 == k->bodywrites && !is_empty_data) {
528        /* These checks are only made the first time we are about to
529           write a piece of the body */
530        if(conn->handler->protocol&(PROTO_FAMILY_HTTP|CURLPROTO_RTSP)) {
531          /* HTTP-only checks */
532
533          if(data->req.newurl) {
534            if(conn->bits.close) {
535              /* Abort after the headers if "follow Location" is set
536                 and we're set to close anyway. */
537              k->keepon &= ~KEEP_RECV;
538              *done = TRUE;
539              return CURLE_OK;
540            }
541            /* We have a new url to load, but since we want to be able
542               to re-use this connection properly, we read the full
543               response in "ignore more" */
544            k->ignorebody = TRUE;
545            infof(data, "Ignoring the response-body\n");
546          }
547          if(data->state.resume_from && !k->content_range &&
548             (data->set.httpreq==HTTPREQ_GET) &&
549             !k->ignorebody) {
550            /* we wanted to resume a download, although the server doesn't
551             * seem to support this and we did this with a GET (if it
552             * wasn't a GET we did a POST or PUT resume) */
553            failf(data, "HTTP server doesn't seem to support "
554                  "byte ranges. Cannot resume.");
555            return CURLE_RANGE_ERROR;
556          }
557
558          if(data->set.timecondition && !data->state.range) {
559            /* A time condition has been set AND no ranges have been
560               requested. This seems to be what chapter 13.3.4 of
561               RFC 2616 defines to be the correct action for a
562               HTTP/1.1 client */
563
564            if(!Curl_meets_timecondition(data, k->timeofdoc)) {
565              *done = TRUE;
566              /* We're simulating a http 304 from server so we return
567                 what should have been returned from the server */
568              data->info.httpcode = 304;
569              infof(data, "Simulate a HTTP 304 response!\n");
570              /* we abort the transfer before it is completed == we ruin the
571                 re-use ability. Close the connection */
572              connclose(conn, "Simulated 304 handling");
573              return CURLE_OK;
574            }
575          } /* we have a time condition */
576
577        } /* this is HTTP or RTSP */
578      } /* this is the first time we write a body part */
579#endif /* CURL_DISABLE_HTTP */
580
581      k->bodywrites++;
582
583      /* pass data to the debug function before it gets "dechunked" */
584      if(data->set.verbose) {
585        if(k->badheader) {
586          Curl_debug(data, CURLINFO_DATA_IN, data->state.headerbuff,
587                     (size_t)k->hbuflen, conn);
588          if(k->badheader == HEADER_PARTHEADER)
589            Curl_debug(data, CURLINFO_DATA_IN,
590                       k->str, (size_t)nread, conn);
591        }
592        else
593          Curl_debug(data, CURLINFO_DATA_IN,
594                     k->str, (size_t)nread, conn);
595      }
596
597#ifndef CURL_DISABLE_HTTP
598      if(k->chunk) {
599        /*
600         * Here comes a chunked transfer flying and we need to decode this
601         * properly.  While the name says read, this function both reads
602         * and writes away the data. The returned 'nread' holds the number
603         * of actual data it wrote to the client.
604         */
605
606        CHUNKcode res =
607          Curl_httpchunk_read(conn, k->str, nread, &nread);
608
609        if(CHUNKE_OK < res) {
610          if(CHUNKE_WRITE_ERROR == res) {
611            failf(data, "Failed writing data");
612            return CURLE_WRITE_ERROR;
613          }
614          failf(data, "%s in chunked-encoding", Curl_chunked_strerror(res));
615          return CURLE_RECV_ERROR;
616        }
617        else if(CHUNKE_STOP == res) {
618          size_t dataleft;
619          /* we're done reading chunks! */
620          k->keepon &= ~KEEP_RECV; /* read no more */
621
622          /* There are now possibly N number of bytes at the end of the
623             str buffer that weren't written to the client.
624
625             We DO care about this data if we are pipelining.
626             Push it back to be read on the next pass. */
627
628          dataleft = conn->chunk.dataleft;
629          if(dataleft != 0) {
630            infof(conn->data, "Leftovers after chunking: %zu bytes\n",
631                  dataleft);
632            if(Curl_multi_pipeline_enabled(conn->data->multi)) {
633              /* only attempt the rewind if we truly are pipelining */
634              infof(conn->data, "Rewinding %zu bytes\n",dataleft);
635              read_rewind(conn, dataleft);
636            }
637          }
638        }
639        /* If it returned OK, we just keep going */
640      }
641#endif   /* CURL_DISABLE_HTTP */
642
643      /* Account for body content stored in the header buffer */
644      if(k->badheader && !k->ignorebody) {
645        DEBUGF(infof(data, "Increasing bytecount by %zu from hbuflen\n",
646                     k->hbuflen));
647        k->bytecount += k->hbuflen;
648      }
649
650      if((-1 != k->maxdownload) &&
651         (k->bytecount + nread >= k->maxdownload)) {
652
653        excess = (size_t)(k->bytecount + nread - k->maxdownload);
654        if(excess > 0 && !k->ignorebody) {
655          if(Curl_multi_pipeline_enabled(conn->data->multi)) {
656            /* The 'excess' amount below can't be more than BUFSIZE which
657               always will fit in a size_t */
658            infof(data,
659                  "Rewinding stream by : %zu"
660                  " bytes on url %s (size = %" CURL_FORMAT_CURL_OFF_T
661                  ", maxdownload = %" CURL_FORMAT_CURL_OFF_T
662                  ", bytecount = %" CURL_FORMAT_CURL_OFF_T ", nread = %zd)\n",
663                  excess, data->state.path,
664                  k->size, k->maxdownload, k->bytecount, nread);
665            read_rewind(conn, excess);
666          }
667          else {
668            infof(data,
669                  "Excess found in a non pipelined read:"
670                  " excess = %zu"
671                  ", size = %" CURL_FORMAT_CURL_OFF_T
672                  ", maxdownload = %" CURL_FORMAT_CURL_OFF_T
673                  ", bytecount = %" CURL_FORMAT_CURL_OFF_T "\n",
674                  excess, k->size, k->maxdownload, k->bytecount);
675          }
676        }
677
678        nread = (ssize_t) (k->maxdownload - k->bytecount);
679        if(nread < 0 ) /* this should be unusual */
680          nread = 0;
681
682        k->keepon &= ~KEEP_RECV; /* we're done reading */
683      }
684
685      k->bytecount += nread;
686
687      Curl_pgrsSetDownloadCounter(data, k->bytecount);
688
689      if(!k->chunk && (nread || k->badheader || is_empty_data)) {
690        /* If this is chunky transfer, it was already written */
691
692        if(k->badheader && !k->ignorebody) {
693          /* we parsed a piece of data wrongly assuming it was a header
694             and now we output it as body instead */
695
696          /* Don't let excess data pollute body writes */
697          if(k->maxdownload == -1 || (curl_off_t)k->hbuflen <= k->maxdownload)
698            result = Curl_client_write(conn, CLIENTWRITE_BODY,
699                                       data->state.headerbuff,
700                                       k->hbuflen);
701          else
702            result = Curl_client_write(conn, CLIENTWRITE_BODY,
703                                       data->state.headerbuff,
704                                       (size_t)k->maxdownload);
705
706          if(result)
707            return result;
708        }
709        if(k->badheader < HEADER_ALLBAD) {
710          /* This switch handles various content encodings. If there's an
711             error here, be sure to check over the almost identical code
712             in http_chunks.c.
713             Make sure that ALL_CONTENT_ENCODINGS contains all the
714             encodings handled here. */
715#ifdef HAVE_LIBZ
716          switch (conn->data->set.http_ce_skip ?
717                  IDENTITY : k->auto_decoding) {
718          case IDENTITY:
719#endif
720            /* This is the default when the server sends no
721               Content-Encoding header. See Curl_readwrite_init; the
722               memset() call initializes k->auto_decoding to zero. */
723            if(!k->ignorebody) {
724
725#ifndef CURL_DISABLE_POP3
726              if(conn->handler->protocol&PROTO_FAMILY_POP3)
727                result = Curl_pop3_write(conn, k->str, nread);
728              else
729#endif /* CURL_DISABLE_POP3 */
730
731                result = Curl_client_write(conn, CLIENTWRITE_BODY, k->str,
732                                           nread);
733            }
734#ifdef HAVE_LIBZ
735            break;
736
737          case DEFLATE:
738            /* Assume CLIENTWRITE_BODY; headers are not encoded. */
739            if(!k->ignorebody)
740              result = Curl_unencode_deflate_write(conn, k, nread);
741            break;
742
743          case GZIP:
744            /* Assume CLIENTWRITE_BODY; headers are not encoded. */
745            if(!k->ignorebody)
746              result = Curl_unencode_gzip_write(conn, k, nread);
747            break;
748
749          case COMPRESS:
750          default:
751            failf (data, "Unrecognized content encoding type. "
752                   "libcurl understands `identity', `deflate' and `gzip' "
753                   "content encodings.");
754            result = CURLE_BAD_CONTENT_ENCODING;
755            break;
756          }
757#endif
758        }
759        k->badheader = HEADER_NORMAL; /* taken care of now */
760
761        if(result)
762          return result;
763      }
764
765    } /* if(! header and data to read ) */
766
767    if(conn->handler->readwrite &&
768       (excess > 0 && !conn->bits.stream_was_rewound)) {
769      /* Parse the excess data */
770      k->str += nread;
771      nread = (ssize_t)excess;
772
773      result = conn->handler->readwrite(data, conn, &nread, &readmore);
774      if(result)
775        return result;
776
777      if(readmore)
778        k->keepon |= KEEP_RECV; /* we're not done reading */
779      break;
780    }
781
782    if(is_empty_data) {
783      /* if we received nothing, the server closed the connection and we
784         are done */
785      k->keepon &= ~KEEP_RECV;
786    }
787
788  } while(data_pending(conn));
789
790  if(((k->keepon & (KEEP_RECV|KEEP_SEND)) == KEEP_SEND) &&
791     conn->bits.close ) {
792    /* When we've read the entire thing and the close bit is set, the server
793       may now close the connection. If there's now any kind of sending going
794       on from our side, we need to stop that immediately. */
795    infof(data, "we are done reading and this is set to close, stop send\n");
796    k->keepon &= ~KEEP_SEND; /* no writing anymore either */
797  }
798
799  return CURLE_OK;
800}
801
802/*
803 * Send data to upload to the server, when the socket is writable.
804 */
805static CURLcode readwrite_upload(struct SessionHandle *data,
806                                 struct connectdata *conn,
807                                 struct SingleRequest *k,
808                                 int *didwhat)
809{
810  ssize_t i, si;
811  ssize_t bytes_written;
812  CURLcode result;
813  ssize_t nread; /* number of bytes read */
814  bool sending_http_headers = FALSE;
815
816  if((k->bytecount == 0) && (k->writebytecount == 0))
817    Curl_pgrsTime(data, TIMER_STARTTRANSFER);
818
819  *didwhat |= KEEP_SEND;
820
821  /*
822   * We loop here to do the READ and SEND loop until we run out of
823   * data to send or until we get EWOULDBLOCK back
824   *
825   * FIXME: above comment is misleading. Currently no looping is
826   * actually done in do-while loop below.
827   */
828  do {
829
830    /* only read more data if there's no upload data already
831       present in the upload buffer */
832    if(0 == data->req.upload_present) {
833      /* init the "upload from here" pointer */
834      data->req.upload_fromhere = k->uploadbuf;
835
836      if(!k->upload_done) {
837        /* HTTP pollution, this should be written nicer to become more
838           protocol agnostic. */
839        int fillcount;
840        struct HTTP *http = data->req.protop;
841
842        if((k->exp100 == EXP100_SENDING_REQUEST) &&
843           (http->sending == HTTPSEND_BODY)) {
844          /* If this call is to send body data, we must take some action:
845             We have sent off the full HTTP 1.1 request, and we shall now
846             go into the Expect: 100 state and await such a header */
847          k->exp100 = EXP100_AWAITING_CONTINUE; /* wait for the header */
848          k->keepon &= ~KEEP_SEND;         /* disable writing */
849          k->start100 = Curl_tvnow();       /* timeout count starts now */
850          *didwhat &= ~KEEP_SEND;  /* we didn't write anything actually */
851
852          /* set a timeout for the multi interface */
853          Curl_expire(data, data->set.expect_100_timeout);
854          break;
855        }
856
857        if(conn->handler->protocol&(PROTO_FAMILY_HTTP|CURLPROTO_RTSP)) {
858          if(http->sending == HTTPSEND_REQUEST)
859            /* We're sending the HTTP request headers, not the data.
860               Remember that so we don't change the line endings. */
861            sending_http_headers = TRUE;
862          else
863            sending_http_headers = FALSE;
864        }
865
866        result = Curl_fillreadbuffer(conn, BUFSIZE, &fillcount);
867        if(result)
868          return result;
869
870        nread = (ssize_t)fillcount;
871      }
872      else
873        nread = 0; /* we're done uploading/reading */
874
875      if(!nread && (k->keepon & KEEP_SEND_PAUSE)) {
876        /* this is a paused transfer */
877        break;
878      }
879      else if(nread<=0) {
880        /* done */
881        k->keepon &= ~KEEP_SEND; /* we're done writing */
882
883        if(conn->bits.rewindaftersend) {
884          result = Curl_readrewind(conn);
885          if(result)
886            return result;
887        }
888        break;
889      }
890
891      /* store number of bytes available for upload */
892      data->req.upload_present = nread;
893
894#ifndef CURL_DISABLE_SMTP
895      if(conn->handler->protocol & PROTO_FAMILY_SMTP) {
896        result = Curl_smtp_escape_eob(conn, nread);
897        if(result)
898          return result;
899      }
900      else
901#endif /* CURL_DISABLE_SMTP */
902
903      /* convert LF to CRLF if so asked */
904      if((!sending_http_headers) && (
905#ifdef CURL_DO_LINEEND_CONV
906         /* always convert if we're FTPing in ASCII mode */
907         (data->set.prefer_ascii) ||
908#endif
909         (data->set.crlf))) {
910        if(data->state.scratch == NULL)
911          data->state.scratch = malloc(2*BUFSIZE);
912        if(data->state.scratch == NULL) {
913          failf (data, "Failed to alloc scratch buffer!");
914          return CURLE_OUT_OF_MEMORY;
915        }
916        /*
917         * ASCII/EBCDIC Note: This is presumably a text (not binary)
918         * transfer so the data should already be in ASCII.
919         * That means the hex values for ASCII CR (0x0d) & LF (0x0a)
920         * must be used instead of the escape sequences \r & \n.
921         */
922        for(i = 0, si = 0; i < nread; i++, si++) {
923          if(data->req.upload_fromhere[i] == 0x0a) {
924            data->state.scratch[si++] = 0x0d;
925            data->state.scratch[si] = 0x0a;
926            if(!data->set.crlf) {
927              /* we're here only because FTP is in ASCII mode...
928                 bump infilesize for the LF we just added */
929              data->state.infilesize++;
930            }
931          }
932          else
933            data->state.scratch[si] = data->req.upload_fromhere[i];
934        }
935        if(si != nread) {
936          /* only perform the special operation if we really did replace
937             anything */
938          nread = si;
939
940          /* upload from the new (replaced) buffer instead */
941          data->req.upload_fromhere = data->state.scratch;
942
943          /* set the new amount too */
944          data->req.upload_present = nread;
945        }
946      }
947    } /* if 0 == data->req.upload_present */
948    else {
949      /* We have a partial buffer left from a previous "round". Use
950         that instead of reading more data */
951    }
952
953    /* write to socket (send away data) */
954    result = Curl_write(conn,
955                        conn->writesockfd,     /* socket to send to */
956                        data->req.upload_fromhere, /* buffer pointer */
957                        data->req.upload_present,  /* buffer size */
958                        &bytes_written);           /* actually sent */
959
960    if(result)
961      return result;
962
963    if(data->set.verbose)
964      /* show the data before we change the pointer upload_fromhere */
965      Curl_debug(data, CURLINFO_DATA_OUT, data->req.upload_fromhere,
966                 (size_t)bytes_written, conn);
967
968    k->writebytecount += bytes_written;
969
970    if(k->writebytecount == data->state.infilesize) {
971      /* we have sent all data we were supposed to */
972      k->upload_done = TRUE;
973      infof(data, "We are completely uploaded and fine\n");
974    }
975
976    if(data->req.upload_present != bytes_written) {
977      /* we only wrote a part of the buffer (if anything), deal with it! */
978
979      /* store the amount of bytes left in the buffer to write */
980      data->req.upload_present -= bytes_written;
981
982      /* advance the pointer where to find the buffer when the next send
983         is to happen */
984      data->req.upload_fromhere += bytes_written;
985    }
986    else {
987      /* we've uploaded that buffer now */
988      data->req.upload_fromhere = k->uploadbuf;
989      data->req.upload_present = 0; /* no more bytes left */
990
991      if(k->upload_done) {
992        /* switch off writing, we're done! */
993        k->keepon &= ~KEEP_SEND; /* we're done writing */
994      }
995    }
996
997    Curl_pgrsSetUploadCounter(data, k->writebytecount);
998
999  } WHILE_FALSE; /* just to break out from! */
1000
1001  return CURLE_OK;
1002}
1003
1004/*
1005 * Curl_readwrite() is the low-level function to be called when data is to
1006 * be read and written to/from the connection.
1007 */
1008CURLcode Curl_readwrite(struct connectdata *conn,
1009                        bool *done)
1010{
1011  struct SessionHandle *data = conn->data;
1012  struct SingleRequest *k = &data->req;
1013  CURLcode result;
1014  int didwhat=0;
1015
1016  curl_socket_t fd_read;
1017  curl_socket_t fd_write;
1018  int select_res = conn->cselect_bits;
1019
1020  conn->cselect_bits = 0;
1021
1022  /* only use the proper socket if the *_HOLD bit is not set simultaneously as
1023     then we are in rate limiting state in that transfer direction */
1024
1025  if((k->keepon & KEEP_RECVBITS) == KEEP_RECV)
1026    fd_read = conn->sockfd;
1027  else
1028    fd_read = CURL_SOCKET_BAD;
1029
1030  if((k->keepon & KEEP_SENDBITS) == KEEP_SEND)
1031    fd_write = conn->writesockfd;
1032  else
1033    fd_write = CURL_SOCKET_BAD;
1034
1035  if(!select_res) /* Call for select()/poll() only, if read/write/error
1036                     status is not known. */
1037    select_res = Curl_socket_ready(fd_read, fd_write, 0);
1038
1039  if(select_res == CURL_CSELECT_ERR) {
1040    failf(data, "select/poll returned error");
1041    return CURLE_SEND_ERROR;
1042  }
1043
1044  /* We go ahead and do a read if we have a readable socket or if
1045     the stream was rewound (in which case we have data in a
1046     buffer) */
1047  if((k->keepon & KEEP_RECV) &&
1048     ((select_res & CURL_CSELECT_IN) || conn->bits.stream_was_rewound)) {
1049
1050    result = readwrite_data(data, conn, k, &didwhat, done);
1051    if(result || *done)
1052      return result;
1053  }
1054
1055  /* If we still have writing to do, we check if we have a writable socket. */
1056  if((k->keepon & KEEP_SEND) && (select_res & CURL_CSELECT_OUT)) {
1057    /* write */
1058
1059    result = readwrite_upload(data, conn, k, &didwhat);
1060    if(result)
1061      return result;
1062  }
1063
1064  k->now = Curl_tvnow();
1065  if(didwhat) {
1066    /* Update read/write counters */
1067    if(k->bytecountp)
1068      *k->bytecountp = k->bytecount; /* read count */
1069    if(k->writebytecountp)
1070      *k->writebytecountp = k->writebytecount; /* write count */
1071  }
1072  else {
1073    /* no read no write, this is a timeout? */
1074    if(k->exp100 == EXP100_AWAITING_CONTINUE) {
1075      /* This should allow some time for the header to arrive, but only a
1076         very short time as otherwise it'll be too much wasted time too
1077         often. */
1078
1079      /* Quoting RFC2616, section "8.2.3 Use of the 100 (Continue) Status":
1080
1081         Therefore, when a client sends this header field to an origin server
1082         (possibly via a proxy) from which it has never seen a 100 (Continue)
1083         status, the client SHOULD NOT wait for an indefinite period before
1084         sending the request body.
1085
1086      */
1087
1088      long ms = Curl_tvdiff(k->now, k->start100);
1089      if(ms >= data->set.expect_100_timeout) {
1090        /* we've waited long enough, continue anyway */
1091        k->exp100 = EXP100_SEND_DATA;
1092        k->keepon |= KEEP_SEND;
1093        infof(data, "Done waiting for 100-continue\n");
1094      }
1095    }
1096  }
1097
1098  if(Curl_pgrsUpdate(conn))
1099    result = CURLE_ABORTED_BY_CALLBACK;
1100  else
1101    result = Curl_speedcheck(data, k->now);
1102  if(result)
1103    return result;
1104
1105  if(k->keepon) {
1106    if(0 > Curl_timeleft(data, &k->now, FALSE)) {
1107      if(k->size != -1) {
1108        failf(data, "Operation timed out after %ld milliseconds with %"
1109              CURL_FORMAT_CURL_OFF_T " out of %"
1110              CURL_FORMAT_CURL_OFF_T " bytes received",
1111              Curl_tvdiff(k->now, data->progress.t_startsingle), k->bytecount,
1112              k->size);
1113      }
1114      else {
1115        failf(data, "Operation timed out after %ld milliseconds with %"
1116              CURL_FORMAT_CURL_OFF_T " bytes received",
1117              Curl_tvdiff(k->now, data->progress.t_startsingle), k->bytecount);
1118      }
1119      return CURLE_OPERATION_TIMEDOUT;
1120    }
1121  }
1122  else {
1123    /*
1124     * The transfer has been performed. Just make some general checks before
1125     * returning.
1126     */
1127
1128    if(!(data->set.opt_no_body) && (k->size != -1) &&
1129       (k->bytecount != k->size) &&
1130#ifdef CURL_DO_LINEEND_CONV
1131       /* Most FTP servers don't adjust their file SIZE response for CRLFs,
1132          so we'll check to see if the discrepancy can be explained
1133          by the number of CRLFs we've changed to LFs.
1134       */
1135       (k->bytecount != (k->size + data->state.crlf_conversions)) &&
1136#endif /* CURL_DO_LINEEND_CONV */
1137       !data->req.newurl) {
1138      failf(data, "transfer closed with %" CURL_FORMAT_CURL_OFF_T
1139            " bytes remaining to read",
1140            k->size - k->bytecount);
1141      return CURLE_PARTIAL_FILE;
1142    }
1143    else if(!(data->set.opt_no_body) &&
1144            k->chunk &&
1145            (conn->chunk.state != CHUNK_STOP)) {
1146      /*
1147       * In chunked mode, return an error if the connection is closed prior to
1148       * the empty (terminating) chunk is read.
1149       *
1150       * The condition above used to check for
1151       * conn->proto.http->chunk.datasize != 0 which is true after reading
1152       * *any* chunk, not just the empty chunk.
1153       *
1154       */
1155      failf(data, "transfer closed with outstanding read data remaining");
1156      return CURLE_PARTIAL_FILE;
1157    }
1158    if(Curl_pgrsUpdate(conn))
1159      return CURLE_ABORTED_BY_CALLBACK;
1160  }
1161
1162  /* Now update the "done" boolean we return */
1163  *done = (0 == (k->keepon&(KEEP_RECV|KEEP_SEND|
1164                            KEEP_RECV_PAUSE|KEEP_SEND_PAUSE))) ? TRUE : FALSE;
1165
1166  return CURLE_OK;
1167}
1168
1169/*
1170 * Curl_single_getsock() gets called by the multi interface code when the app
1171 * has requested to get the sockets for the current connection. This function
1172 * will then be called once for every connection that the multi interface
1173 * keeps track of. This function will only be called for connections that are
1174 * in the proper state to have this information available.
1175 */
1176int Curl_single_getsock(const struct connectdata *conn,
1177                        curl_socket_t *sock, /* points to numsocks number
1178                                                of sockets */
1179                        int numsocks)
1180{
1181  const struct SessionHandle *data = conn->data;
1182  int bitmap = GETSOCK_BLANK;
1183  unsigned sockindex = 0;
1184
1185  if(conn->handler->perform_getsock)
1186    return conn->handler->perform_getsock(conn, sock, numsocks);
1187
1188  if(numsocks < 2)
1189    /* simple check but we might need two slots */
1190    return GETSOCK_BLANK;
1191
1192  /* don't include HOLD and PAUSE connections */
1193  if((data->req.keepon & KEEP_RECVBITS) == KEEP_RECV) {
1194
1195    DEBUGASSERT(conn->sockfd != CURL_SOCKET_BAD);
1196
1197    bitmap |= GETSOCK_READSOCK(sockindex);
1198    sock[sockindex] = conn->sockfd;
1199  }
1200
1201  /* don't include HOLD and PAUSE connections */
1202  if((data->req.keepon & KEEP_SENDBITS) == KEEP_SEND) {
1203
1204    if((conn->sockfd != conn->writesockfd) ||
1205       !(data->req.keepon & KEEP_RECV)) {
1206      /* only if they are not the same socket or we didn't have a readable
1207         one, we increase index */
1208      if(data->req.keepon & KEEP_RECV)
1209        sockindex++; /* increase index if we need two entries */
1210
1211      DEBUGASSERT(conn->writesockfd != CURL_SOCKET_BAD);
1212
1213      sock[sockindex] = conn->writesockfd;
1214    }
1215
1216    bitmap |= GETSOCK_WRITESOCK(sockindex);
1217  }
1218
1219  return bitmap;
1220}
1221
1222/*
1223 * Determine optimum sleep time based on configured rate, current rate,
1224 * and packet size.
1225 * Returns value in milliseconds.
1226 *
1227 * The basic idea is to adjust the desired rate up/down in this method
1228 * based on whether we are running too slow or too fast.  Then, calculate
1229 * how many milliseconds to wait for the next packet to achieve this new
1230 * rate.
1231 */
1232long Curl_sleep_time(curl_off_t rate_bps, curl_off_t cur_rate_bps,
1233                             int pkt_size)
1234{
1235  curl_off_t min_sleep = 0;
1236  curl_off_t rv = 0;
1237
1238  if(rate_bps == 0)
1239    return 0;
1240
1241  /* If running faster than about .1% of the desired speed, slow
1242   * us down a bit.  Use shift instead of division as the 0.1%
1243   * cutoff is arbitrary anyway.
1244   */
1245  if(cur_rate_bps > (rate_bps + (rate_bps >> 10))) {
1246    /* running too fast, decrease target rate by 1/64th of rate */
1247    rate_bps -= rate_bps >> 6;
1248    min_sleep = 1;
1249  }
1250  else if(cur_rate_bps < (rate_bps - (rate_bps >> 10))) {
1251    /* running too slow, increase target rate by 1/64th of rate */
1252    rate_bps += rate_bps >> 6;
1253  }
1254
1255  /* Determine number of milliseconds to wait until we do
1256   * the next packet at the adjusted rate.  We should wait
1257   * longer when using larger packets, for instance.
1258   */
1259  rv = ((curl_off_t)((pkt_size * 8) * 1000) / rate_bps);
1260
1261  /* Catch rounding errors and always slow down at least 1ms if
1262   * we are running too fast.
1263   */
1264  if(rv < min_sleep)
1265    rv = min_sleep;
1266
1267  /* Bound value to fit in 'long' on 32-bit platform.  That's
1268   * plenty long enough anyway!
1269   */
1270  if(rv > 0x7fffffff)
1271    rv = 0x7fffffff;
1272
1273  return (long)rv;
1274}
1275
1276/*
1277 * Curl_pretransfer() is called immediately before a transfer starts.
1278 */
1279CURLcode Curl_pretransfer(struct SessionHandle *data)
1280{
1281  CURLcode res;
1282  if(!data->change.url) {
1283    /* we can't do anything without URL */
1284    failf(data, "No URL set!");
1285    return CURLE_URL_MALFORMAT;
1286  }
1287
1288  /* Init the SSL session ID cache here. We do it here since we want to do it
1289     after the *_setopt() calls (that could specify the size of the cache) but
1290     before any transfer takes place. */
1291  res = Curl_ssl_initsessions(data, data->set.ssl.max_ssl_sessions);
1292  if(res)
1293    return res;
1294
1295  data->set.followlocation=0; /* reset the location-follow counter */
1296  data->state.this_is_a_follow = FALSE; /* reset this */
1297  data->state.errorbuf = FALSE; /* no error has occurred */
1298  data->state.httpversion = 0; /* don't assume any particular server version */
1299
1300  data->state.ssl_connect_retry = FALSE;
1301
1302  data->state.authproblem = FALSE;
1303  data->state.authhost.want = data->set.httpauth;
1304  data->state.authproxy.want = data->set.proxyauth;
1305  Curl_safefree(data->info.wouldredirect);
1306  data->info.wouldredirect = NULL;
1307
1308  /* If there is a list of cookie files to read, do it now! */
1309  if(data->change.cookielist)
1310    Curl_cookie_loadfiles(data);
1311
1312  /* If there is a list of host pairs to deal with */
1313  if(data->change.resolve)
1314    res = Curl_loadhostpairs(data);
1315
1316  if(!res) {
1317    /* Allow data->set.use_port to set which port to use. This needs to be
1318     * disabled for example when we follow Location: headers to URLs using
1319     * different ports! */
1320    data->state.allow_port = TRUE;
1321
1322#if defined(HAVE_SIGNAL) && defined(SIGPIPE) && !defined(HAVE_MSG_NOSIGNAL)
1323    /*************************************************************
1324     * Tell signal handler to ignore SIGPIPE
1325     *************************************************************/
1326    if(!data->set.no_signal)
1327      data->state.prev_signal = signal(SIGPIPE, SIG_IGN);
1328#endif
1329
1330    Curl_initinfo(data); /* reset session-specific information "variables" */
1331    Curl_pgrsStartNow(data);
1332
1333    if(data->set.timeout)
1334      Curl_expire(data, data->set.timeout);
1335
1336    if(data->set.connecttimeout)
1337      Curl_expire(data, data->set.connecttimeout);
1338
1339    /* In case the handle is re-used and an authentication method was picked
1340       in the session we need to make sure we only use the one(s) we now
1341       consider to be fine */
1342    data->state.authhost.picked &= data->state.authhost.want;
1343    data->state.authproxy.picked &= data->state.authproxy.want;
1344  }
1345
1346  return res;
1347}
1348
1349/*
1350 * Curl_posttransfer() is called immediately after a transfer ends
1351 */
1352CURLcode Curl_posttransfer(struct SessionHandle *data)
1353{
1354#if defined(HAVE_SIGNAL) && defined(SIGPIPE) && !defined(HAVE_MSG_NOSIGNAL)
1355  /* restore the signal handler for SIGPIPE before we get back */
1356  if(!data->set.no_signal)
1357    signal(SIGPIPE, data->state.prev_signal);
1358#else
1359  (void)data; /* unused parameter */
1360#endif
1361
1362  return CURLE_OK;
1363}
1364
1365#ifndef CURL_DISABLE_HTTP
1366/*
1367 * strlen_url() returns the length of the given URL if the spaces within the
1368 * URL were properly URL encoded.
1369 */
1370static size_t strlen_url(const char *url)
1371{
1372  const char *ptr;
1373  size_t newlen=0;
1374  bool left=TRUE; /* left side of the ? */
1375
1376  for(ptr=url; *ptr; ptr++) {
1377    switch(*ptr) {
1378    case '?':
1379      left=FALSE;
1380      /* fall through */
1381    default:
1382      newlen++;
1383      break;
1384    case ' ':
1385      if(left)
1386        newlen+=3;
1387      else
1388        newlen++;
1389      break;
1390    }
1391  }
1392  return newlen;
1393}
1394
1395/* strcpy_url() copies a url to a output buffer and URL-encodes the spaces in
1396 * the source URL accordingly.
1397 */
1398static void strcpy_url(char *output, const char *url)
1399{
1400  /* we must add this with whitespace-replacing */
1401  bool left=TRUE;
1402  const char *iptr;
1403  char *optr = output;
1404  for(iptr = url;    /* read from here */
1405      *iptr;         /* until zero byte */
1406      iptr++) {
1407    switch(*iptr) {
1408    case '?':
1409      left=FALSE;
1410      /* fall through */
1411    default:
1412      *optr++=*iptr;
1413      break;
1414    case ' ':
1415      if(left) {
1416        *optr++='%'; /* add a '%' */
1417        *optr++='2'; /* add a '2' */
1418        *optr++='0'; /* add a '0' */
1419      }
1420      else
1421        *optr++='+'; /* add a '+' here */
1422      break;
1423    }
1424  }
1425  *optr=0; /* zero terminate output buffer */
1426
1427}
1428
1429/*
1430 * Returns true if the given URL is absolute (as opposed to relative)
1431 */
1432static bool is_absolute_url(const char *url)
1433{
1434  char prot[16]; /* URL protocol string storage */
1435  char letter;   /* used for a silly sscanf */
1436
1437  return (2 == sscanf(url, "%15[^?&/:]://%c", prot, &letter)) ? TRUE : FALSE;
1438}
1439
1440/*
1441 * Concatenate a relative URL to a base URL making it absolute.
1442 * URL-encodes any spaces.
1443 * The returned pointer must be freed by the caller unless NULL
1444 * (returns NULL on out of memory).
1445 */
1446static char *concat_url(const char *base, const char *relurl)
1447{
1448  /***
1449   TRY to append this new path to the old URL
1450   to the right of the host part. Oh crap, this is doomed to cause
1451   problems in the future...
1452  */
1453  char *newest;
1454  char *protsep;
1455  char *pathsep;
1456  size_t newlen;
1457
1458  const char *useurl = relurl;
1459  size_t urllen;
1460
1461  /* we must make our own copy of the URL to play with, as it may
1462     point to read-only data */
1463  char *url_clone=strdup(base);
1464
1465  if(!url_clone)
1466    return NULL; /* skip out of this NOW */
1467
1468  /* protsep points to the start of the host name */
1469  protsep=strstr(url_clone, "//");
1470  if(!protsep)
1471    protsep=url_clone;
1472  else
1473    protsep+=2; /* pass the slashes */
1474
1475  if('/' != relurl[0]) {
1476    int level=0;
1477
1478    /* First we need to find out if there's a ?-letter in the URL,
1479       and cut it and the right-side of that off */
1480    pathsep = strchr(protsep, '?');
1481    if(pathsep)
1482      *pathsep=0;
1483
1484    /* we have a relative path to append to the last slash if there's one
1485       available, or if the new URL is just a query string (starts with a
1486       '?')  we append the new one at the end of the entire currently worked
1487       out URL */
1488    if(useurl[0] != '?') {
1489      pathsep = strrchr(protsep, '/');
1490      if(pathsep)
1491        *pathsep=0;
1492    }
1493
1494    /* Check if there's any slash after the host name, and if so, remember
1495       that position instead */
1496    pathsep = strchr(protsep, '/');
1497    if(pathsep)
1498      protsep = pathsep+1;
1499    else
1500      protsep = NULL;
1501
1502    /* now deal with one "./" or any amount of "../" in the newurl
1503       and act accordingly */
1504
1505    if((useurl[0] == '.') && (useurl[1] == '/'))
1506      useurl+=2; /* just skip the "./" */
1507
1508    while((useurl[0] == '.') &&
1509          (useurl[1] == '.') &&
1510          (useurl[2] == '/')) {
1511      level++;
1512      useurl+=3; /* pass the "../" */
1513    }
1514
1515    if(protsep) {
1516      while(level--) {
1517        /* cut off one more level from the right of the original URL */
1518        pathsep = strrchr(protsep, '/');
1519        if(pathsep)
1520          *pathsep=0;
1521        else {
1522          *protsep=0;
1523          break;
1524        }
1525      }
1526    }
1527  }
1528  else {
1529    /* We got a new absolute path for this server */
1530
1531    if((relurl[0] == '/') && (relurl[1] == '/')) {
1532      /* the new URL starts with //, just keep the protocol part from the
1533         original one */
1534      *protsep=0;
1535      useurl = &relurl[2]; /* we keep the slashes from the original, so we
1536                              skip the new ones */
1537    }
1538    else {
1539      /* cut off the original URL from the first slash, or deal with URLs
1540         without slash */
1541      pathsep = strchr(protsep, '/');
1542      if(pathsep) {
1543        /* When people use badly formatted URLs, such as
1544           "http://www.url.com?dir=/home/daniel" we must not use the first
1545           slash, if there's a ?-letter before it! */
1546        char *sep = strchr(protsep, '?');
1547        if(sep && (sep < pathsep))
1548          pathsep = sep;
1549        *pathsep=0;
1550      }
1551      else {
1552        /* There was no slash. Now, since we might be operating on a badly
1553           formatted URL, such as "http://www.url.com?id=2380" which doesn't
1554           use a slash separator as it is supposed to, we need to check for a
1555           ?-letter as well! */
1556        pathsep = strchr(protsep, '?');
1557        if(pathsep)
1558          *pathsep=0;
1559      }
1560    }
1561  }
1562
1563  /* If the new part contains a space, this is a mighty stupid redirect
1564     but we still make an effort to do "right". To the left of a '?'
1565     letter we replace each space with %20 while it is replaced with '+'
1566     on the right side of the '?' letter.
1567  */
1568  newlen = strlen_url(useurl);
1569
1570  urllen = strlen(url_clone);
1571
1572  newest = malloc(urllen + 1 + /* possible slash */
1573                  newlen + 1 /* zero byte */);
1574
1575  if(!newest) {
1576    free(url_clone); /* don't leak this */
1577    return NULL;
1578  }
1579
1580  /* copy over the root url part */
1581  memcpy(newest, url_clone, urllen);
1582
1583  /* check if we need to append a slash */
1584  if(('/' == useurl[0]) || (protsep && !*protsep) || ('?' == useurl[0]))
1585    ;
1586  else
1587    newest[urllen++]='/';
1588
1589  /* then append the new piece on the right side */
1590  strcpy_url(&newest[urllen], useurl);
1591
1592  free(url_clone);
1593
1594  return newest;
1595}
1596#endif /* CURL_DISABLE_HTTP */
1597
1598/*
1599 * Curl_follow() handles the URL redirect magic. Pass in the 'newurl' string
1600 * as given by the remote server and set up the new URL to request.
1601 */
1602CURLcode Curl_follow(struct SessionHandle *data,
1603                     char *newurl, /* this 'newurl' is the Location: string,
1604                                      and it must be malloc()ed before passed
1605                                      here */
1606                     followtype type) /* see transfer.h */
1607{
1608#ifdef CURL_DISABLE_HTTP
1609  (void)data;
1610  (void)newurl;
1611  (void)type;
1612  /* Location: following will not happen when HTTP is disabled */
1613  return CURLE_TOO_MANY_REDIRECTS;
1614#else
1615
1616  /* Location: redirect */
1617  bool disallowport = FALSE;
1618
1619  if(type == FOLLOW_REDIR) {
1620    if((data->set.maxredirs != -1) &&
1621        (data->set.followlocation >= data->set.maxredirs)) {
1622      failf(data,"Maximum (%ld) redirects followed", data->set.maxredirs);
1623      return CURLE_TOO_MANY_REDIRECTS;
1624    }
1625
1626    /* mark the next request as a followed location: */
1627    data->state.this_is_a_follow = TRUE;
1628
1629    data->set.followlocation++; /* count location-followers */
1630
1631    if(data->set.http_auto_referer) {
1632      /* We are asked to automatically set the previous URL as the referer
1633         when we get the next URL. We pick the ->url field, which may or may
1634         not be 100% correct */
1635
1636      if(data->change.referer_alloc) {
1637        Curl_safefree(data->change.referer);
1638        data->change.referer_alloc = FALSE;
1639      }
1640
1641      data->change.referer = strdup(data->change.url);
1642      if(!data->change.referer)
1643        return CURLE_OUT_OF_MEMORY;
1644      data->change.referer_alloc = TRUE; /* yes, free this later */
1645    }
1646  }
1647
1648  if(!is_absolute_url(newurl))  {
1649    /***
1650     *DANG* this is an RFC 2068 violation. The URL is supposed
1651     to be absolute and this doesn't seem to be that!
1652     */
1653    char *absolute = concat_url(data->change.url, newurl);
1654    if(!absolute)
1655      return CURLE_OUT_OF_MEMORY;
1656    free(newurl);
1657    newurl = absolute;
1658  }
1659  else {
1660    /* This is an absolute URL, don't allow the custom port number */
1661    disallowport = TRUE;
1662
1663    if(strchr(newurl, ' ')) {
1664      /* This new URL contains at least one space, this is a mighty stupid
1665         redirect but we still make an effort to do "right". */
1666      char *newest;
1667      size_t newlen = strlen_url(newurl);
1668
1669      newest = malloc(newlen+1); /* get memory for this */
1670      if(!newest)
1671        return CURLE_OUT_OF_MEMORY;
1672      strcpy_url(newest, newurl); /* create a space-free URL */
1673
1674      free(newurl); /* that was no good */
1675      newurl = newest; /* use this instead now */
1676    }
1677
1678  }
1679
1680  if(type == FOLLOW_FAKE) {
1681    /* we're only figuring out the new url if we would've followed locations
1682       but now we're done so we can get out! */
1683    data->info.wouldredirect = newurl;
1684    return CURLE_OK;
1685  }
1686
1687  if(disallowport)
1688    data->state.allow_port = FALSE;
1689
1690  if(data->change.url_alloc) {
1691    Curl_safefree(data->change.url);
1692    data->change.url_alloc = FALSE;
1693  }
1694
1695  data->change.url = newurl;
1696  data->change.url_alloc = TRUE;
1697  newurl = NULL; /* don't free! */
1698
1699  infof(data, "Issue another request to this URL: '%s'\n", data->change.url);
1700
1701  /*
1702   * We get here when the HTTP code is 300-399 (and 401). We need to perform
1703   * differently based on exactly what return code there was.
1704   *
1705   * News from 7.10.6: we can also get here on a 401 or 407, in case we act on
1706   * a HTTP (proxy-) authentication scheme other than Basic.
1707   */
1708  switch(data->info.httpcode) {
1709    /* 401 - Act on a WWW-Authenticate, we keep on moving and do the
1710       Authorization: XXXX header in the HTTP request code snippet */
1711    /* 407 - Act on a Proxy-Authenticate, we keep on moving and do the
1712       Proxy-Authorization: XXXX header in the HTTP request code snippet */
1713    /* 300 - Multiple Choices */
1714    /* 306 - Not used */
1715    /* 307 - Temporary Redirect */
1716  default:  /* for all above (and the unknown ones) */
1717    /* Some codes are explicitly mentioned since I've checked RFC2616 and they
1718     * seem to be OK to POST to.
1719     */
1720    break;
1721  case 301: /* Moved Permanently */
1722    /* (quote from RFC7231, section 6.4.2)
1723     *
1724     * Note: For historical reasons, a user agent MAY change the request
1725     * method from POST to GET for the subsequent request.  If this
1726     * behavior is undesired, the 307 (Temporary Redirect) status code
1727     * can be used instead.
1728     *
1729     * ----
1730     *
1731     * Many webservers expect this, so these servers often answers to a POST
1732     * request with an error page. To be sure that libcurl gets the page that
1733     * most user agents would get, libcurl has to force GET.
1734     *
1735     * This behaviour is forbidden by RFC1945 and the obsolete RFC2616, and
1736     * can be overridden with CURLOPT_POSTREDIR.
1737     */
1738    if((data->set.httpreq == HTTPREQ_POST
1739        || data->set.httpreq == HTTPREQ_POST_FORM)
1740       && !(data->set.keep_post & CURL_REDIR_POST_301)) {
1741      infof(data, "Switch from POST to GET\n");
1742      data->set.httpreq = HTTPREQ_GET;
1743    }
1744    break;
1745  case 302: /* Found */
1746    /* (quote from RFC7231, section 6.4.3)
1747     *
1748     * Note: For historical reasons, a user agent MAY change the request
1749     * method from POST to GET for the subsequent request.  If this
1750     * behavior is undesired, the 307 (Temporary Redirect) status code
1751     * can be used instead.
1752     *
1753     * ----
1754     *
1755     * Many webservers expect this, so these servers often answers to a POST
1756     * request with an error page. To be sure that libcurl gets the page that
1757     * most user agents would get, libcurl has to force GET.
1758     *
1759     * This behaviour is forbidden by RFC1945 and the obsolete RFC2616, and
1760     * can be overridden with CURLOPT_POSTREDIR.
1761     */
1762    if((data->set.httpreq == HTTPREQ_POST
1763        || data->set.httpreq == HTTPREQ_POST_FORM)
1764       && !(data->set.keep_post & CURL_REDIR_POST_302)) {
1765      infof(data, "Switch from POST to GET\n");
1766      data->set.httpreq = HTTPREQ_GET;
1767    }
1768    break;
1769
1770  case 303: /* See Other */
1771    /* Disable both types of POSTs, unless the user explicitely
1772       asks for POST after POST */
1773    if(data->set.httpreq != HTTPREQ_GET
1774      && !(data->set.keep_post & CURL_REDIR_POST_303)) {
1775      data->set.httpreq = HTTPREQ_GET; /* enforce GET request */
1776      infof(data, "Disables POST, goes with %s\n",
1777            data->set.opt_no_body?"HEAD":"GET");
1778    }
1779    break;
1780  case 304: /* Not Modified */
1781    /* 304 means we did a conditional request and it was "Not modified".
1782     * We shouldn't get any Location: header in this response!
1783     */
1784    break;
1785  case 305: /* Use Proxy */
1786    /* (quote from RFC2616, section 10.3.6):
1787     * "The requested resource MUST be accessed through the proxy given
1788     * by the Location field. The Location field gives the URI of the
1789     * proxy.  The recipient is expected to repeat this single request
1790     * via the proxy. 305 responses MUST only be generated by origin
1791     * servers."
1792     */
1793    break;
1794  }
1795  Curl_pgrsTime(data, TIMER_REDIRECT);
1796  Curl_pgrsResetTimesSizes(data);
1797
1798  return CURLE_OK;
1799#endif /* CURL_DISABLE_HTTP */
1800}
1801
1802CURLcode
1803Curl_reconnect_request(struct connectdata **connp)
1804{
1805  CURLcode result = CURLE_OK;
1806  struct connectdata *conn = *connp;
1807  struct SessionHandle *data = conn->data;
1808
1809  /* This was a re-use of a connection and we got a write error in the
1810   * DO-phase. Then we DISCONNECT this connection and have another attempt to
1811   * CONNECT and then DO again! The retry cannot possibly find another
1812   * connection to re-use, since we only keep one possible connection for
1813   * each.  */
1814
1815  infof(data, "Re-used connection seems dead, get a new one\n");
1816
1817  connclose(conn, "Reconnect dead connection"); /* enforce close */
1818  result = Curl_done(&conn, result, FALSE); /* we are so done with this */
1819
1820  /* conn may no longer be a good pointer, clear it to avoid mistakes by
1821     parent functions */
1822  *connp = NULL;
1823
1824  /*
1825   * According to bug report #1330310. We need to check for CURLE_SEND_ERROR
1826   * here as well. I figure this could happen when the request failed on a FTP
1827   * connection and thus Curl_done() itself tried to use the connection
1828   * (again). Slight Lack of feedback in the report, but I don't think this
1829   * extra check can do much harm.
1830   */
1831  if((CURLE_OK == result) || (CURLE_SEND_ERROR == result)) {
1832    bool async;
1833    bool protocol_done = TRUE;
1834
1835    /* Now, redo the connect and get a new connection */
1836    result = Curl_connect(data, connp, &async, &protocol_done);
1837    if(CURLE_OK == result) {
1838      /* We have connected or sent away a name resolve query fine */
1839
1840      conn = *connp; /* setup conn to again point to something nice */
1841      if(async) {
1842        /* Now, if async is TRUE here, we need to wait for the name
1843           to resolve */
1844        result = Curl_resolver_wait_resolv(conn, NULL);
1845        if(result)
1846          return result;
1847
1848        /* Resolved, continue with the connection */
1849        result = Curl_async_resolved(conn, &protocol_done);
1850        if(result)
1851          return result;
1852      }
1853    }
1854  }
1855
1856  return result;
1857}
1858
1859/* Returns CURLE_OK *and* sets '*url' if a request retry is wanted.
1860
1861   NOTE: that the *url is malloc()ed. */
1862CURLcode Curl_retry_request(struct connectdata *conn,
1863                            char **url)
1864{
1865  struct SessionHandle *data = conn->data;
1866
1867  *url = NULL;
1868
1869  /* if we're talking upload, we can't do the checks below, unless the protocol
1870     is HTTP as when uploading over HTTP we will still get a response */
1871  if(data->set.upload &&
1872     !(conn->handler->protocol&(PROTO_FAMILY_HTTP|CURLPROTO_RTSP)))
1873    return CURLE_OK;
1874
1875  if(/* workaround for broken TLS servers */ data->state.ssl_connect_retry ||
1876      ((data->req.bytecount +
1877        data->req.headerbytecount == 0) &&
1878        conn->bits.reuse &&
1879        !data->set.opt_no_body &&
1880       data->set.rtspreq != RTSPREQ_RECEIVE)) {
1881    /* We got no data, we attempted to re-use a connection and yet we want a
1882       "body". This might happen if the connection was left alive when we were
1883       done using it before, but that was closed when we wanted to read from
1884       it again. Bad luck. Retry the same request on a fresh connect! */
1885    infof(conn->data, "Connection died, retrying a fresh connect\n");
1886    *url = strdup(conn->data->change.url);
1887    if(!*url)
1888      return CURLE_OUT_OF_MEMORY;
1889
1890    connclose(conn, "retry"); /* close this connection */
1891    conn->bits.retry = TRUE; /* mark this as a connection we're about
1892                                to retry. Marking it this way should
1893                                prevent i.e HTTP transfers to return
1894                                error just because nothing has been
1895                                transferred! */
1896
1897
1898    if(conn->handler->protocol&PROTO_FAMILY_HTTP) {
1899      struct HTTP *http = data->req.protop;
1900      if(http->writebytecount)
1901        return Curl_readrewind(conn);
1902    }
1903  }
1904  return CURLE_OK;
1905}
1906
1907/*
1908 * Curl_setup_transfer() is called to setup some basic properties for the
1909 * upcoming transfer.
1910 */
1911void
1912Curl_setup_transfer(
1913  struct connectdata *conn, /* connection data */
1914  int sockindex,            /* socket index to read from or -1 */
1915  curl_off_t size,          /* -1 if unknown at this point */
1916  bool getheader,           /* TRUE if header parsing is wanted */
1917  curl_off_t *bytecountp,   /* return number of bytes read or NULL */
1918  int writesockindex,       /* socket index to write to, it may very well be
1919                               the same we read from. -1 disables */
1920  curl_off_t *writecountp   /* return number of bytes written or NULL */
1921  )
1922{
1923  struct SessionHandle *data;
1924  struct SingleRequest *k;
1925
1926  DEBUGASSERT(conn != NULL);
1927
1928  data = conn->data;
1929  k = &data->req;
1930
1931  DEBUGASSERT((sockindex <= 1) && (sockindex >= -1));
1932
1933  /* now copy all input parameters */
1934  conn->sockfd = sockindex == -1 ?
1935      CURL_SOCKET_BAD : conn->sock[sockindex];
1936  conn->writesockfd = writesockindex == -1 ?
1937      CURL_SOCKET_BAD:conn->sock[writesockindex];
1938  k->getheader = getheader;
1939
1940  k->size = size;
1941  k->bytecountp = bytecountp;
1942  k->writebytecountp = writecountp;
1943
1944  /* The code sequence below is placed in this function just because all
1945     necessary input is not always known in do_complete() as this function may
1946     be called after that */
1947
1948  if(!k->getheader) {
1949    k->header = FALSE;
1950    if(size > 0)
1951      Curl_pgrsSetDownloadSize(data, size);
1952  }
1953  /* we want header and/or body, if neither then don't do this! */
1954  if(k->getheader || !data->set.opt_no_body) {
1955
1956    if(conn->sockfd != CURL_SOCKET_BAD)
1957      k->keepon |= KEEP_RECV;
1958
1959    if(conn->writesockfd != CURL_SOCKET_BAD) {
1960      struct HTTP *http = data->req.protop;
1961      /* HTTP 1.1 magic:
1962
1963         Even if we require a 100-return code before uploading data, we might
1964         need to write data before that since the REQUEST may not have been
1965         finished sent off just yet.
1966
1967         Thus, we must check if the request has been sent before we set the
1968         state info where we wait for the 100-return code
1969      */
1970      if((data->state.expect100header) &&
1971         (conn->handler->protocol&PROTO_FAMILY_HTTP) &&
1972         (http->sending == HTTPSEND_BODY)) {
1973        /* wait with write until we either got 100-continue or a timeout */
1974        k->exp100 = EXP100_AWAITING_CONTINUE;
1975        k->start100 = Curl_tvnow();
1976
1977        /* Set a timeout for the multi interface. Add the inaccuracy margin so
1978           that we don't fire slightly too early and get denied to run. */
1979        Curl_expire(data, data->set.expect_100_timeout);
1980      }
1981      else {
1982        if(data->state.expect100header)
1983          /* when we've sent off the rest of the headers, we must await a
1984             100-continue but first finish sending the request */
1985          k->exp100 = EXP100_SENDING_REQUEST;
1986
1987        /* enable the write bit when we're not waiting for continue */
1988        k->keepon |= KEEP_SEND;
1989      }
1990    } /* if(conn->writesockfd != CURL_SOCKET_BAD) */
1991  } /* if(k->getheader || !data->set.opt_no_body) */
1992
1993}
1994