libavformat/http.c

   1 /*
   2  * HTTP protocol for avconv client
   3  * Copyright (c) 2000, 2001 Fabrice Bellard
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * Libav is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include "libavutil/avstring.h"
  23 #include "avformat.h"
  24 #include <unistd.h>
  25 #include "internal.h"
  26 #include "network.h"
  27 #include "http.h"
  28 #include "os_support.h"
  29 #include "httpauth.h"
  30 #include "url.h"
  31 #include "libavutil/opt.h"
  32
  33 /* XXX: POST protocol is not completely implemented because avconv uses
  34    only a subset of it. */
  35
  36 /* used for protocol handling */
  37 #define BUFFER_SIZE 1024
  38 #define MAX_REDIRECTS 8
  39
  40 typedef struct {
  41     const AVClass *class;
  42     URLContext *hd;
  43     unsigned char buffer[BUFFER_SIZE], *buf_ptr, *buf_end;
  44     int line_count;
  45     int http_code;
  46     int64_t chunksize;      /**< Used if "Transfer-Encoding: chunked" otherwise -1. */
  47     int64_t off, filesize;
  48     char location[MAX_URL_SIZE];
  49     HTTPAuthState auth_state;
  50     char *headers;
  51     int willclose;          /**< Set if the server correctly handles Connection: close and will close the connection after feeding us the content. */
  52 } HTTPContext;
  53
  54 #define OFFSET(x) offsetof(HTTPContext, x)
  55 static const AVOption options[] = {
  56 {"chunksize", "use chunked transfer-encoding for posts, -1 disables it, 0 enables it", OFFSET(chunksize), AV_OPT_TYPE_INT64, {.dbl = 0}, -1, 0 }, /* Default to 0, for chunked POSTs */
  57 {"headers", "custom HTTP headers, can override built in default headers", OFFSET(headers), AV_OPT_TYPE_STRING },
  58 {NULL}
  59 };
  60 static const AVClass httpcontext_class = {
  61     .class_name     = "HTTP",
  62     .item_name      = av_default_item_name,
  63     .option         = options,
  64     .version        = LIBAVUTIL_VERSION_INT,
  65 };
  66
  67 static int http_connect(URLContext *h, const char *path, const char *hoststr,
  68                         const char *auth, int *new_location);
  69
  70 void ff_http_init_auth_state(URLContext *dest, const URLContext *src)
  71 {
  72     memcpy(&((HTTPContext*)dest->priv_data)->auth_state,
  73            &((HTTPContext*)src->priv_data)->auth_state, sizeof(HTTPAuthState));
  74 }
  75
  76 /* return non zero if error */
  77 static int http_open_cnx(URLContext *h)
  78 {
  79     const char *path, *proxy_path, *lower_proto = "tcp";
  80     char hostname[1024], hoststr[1024], proto[10];
  81     char auth[1024];
  82     char path1[1024];
  83     char buf[1024];
  84     int port, use_proxy, err, location_changed = 0, redirects = 0;
  85     HTTPAuthType cur_auth_type;
  86     HTTPContext *s = h->priv_data;
  87     URLContext *hd = NULL;
  88
  89     proxy_path = getenv("http_proxy");
  90     use_proxy = (proxy_path != NULL) && !getenv("no_proxy") &&
  91         av_strstart(proxy_path, "http://", NULL);
  92
  93     /* fill the dest addr */
  94  redo:
  95     /* needed in any case to build the host string */
  96     av_url_split(proto, sizeof(proto), auth, sizeof(auth),
  97                  hostname, sizeof(hostname), &port,
  98                  path1, sizeof(path1), s->location);
  99     ff_url_join(hoststr, sizeof(hoststr), NULL, NULL, hostname, port, NULL);
 100
 101     if (use_proxy) {
 102         av_url_split(NULL, 0, auth, sizeof(auth), hostname, sizeof(hostname), &port,
 103                      NULL, 0, proxy_path);
 104         path = s->location;
 105     } else {
 106         if (path1[0] == '\0')
 107             path = "/";
 108         else
 109             path = path1;
 110     }
 111     if (!strcmp(proto, "https")) {
 112         lower_proto = "tls";
 113         if (port < 0)
 114             port = 443;
 115     }
 116     if (port < 0)
 117         port = 80;
 118
 119     ff_url_join(buf, sizeof(buf), lower_proto, NULL, hostname, port, NULL);
 120     err = ffurl_open(&hd, buf, AVIO_FLAG_READ_WRITE);
 121     if (err < 0)
 122         goto fail;
 123
 124     s->hd = hd;
 125     cur_auth_type = s->auth_state.auth_type;
 126     if (http_connect(h, path, hoststr, auth, &location_changed) < 0)
 127         goto fail;
 128     if (s->http_code == 401) {
 129         if (cur_auth_type == HTTP_AUTH_NONE && s->auth_state.auth_type != HTTP_AUTH_NONE) {
 130             ffurl_close(hd);
 131             goto redo;
 132         } else
 133             goto fail;
 134     }
 135     if ((s->http_code == 301 || s->http_code == 302 || s->http_code == 303 || s->http_code == 307)
 136         && location_changed == 1) {
 137         /* url moved, get next */
 138         ffurl_close(hd);
 139         if (redirects++ >= MAX_REDIRECTS)
 140             return AVERROR(EIO);
 141         location_changed = 0;
 142         goto redo;
 143     }
 144     return 0;
 145  fail:
 146     if (hd)
 147         ffurl_close(hd);
 148     s->hd = NULL;
 149     return AVERROR(EIO);
 150 }
 151
 152 static int http_open(URLContext *h, const char *uri, int flags)
 153 {
 154     HTTPContext *s = h->priv_data;
 155
 156     h->is_streamed = 1;
 157
 158     s->filesize = -1;
 159     av_strlcpy(s->location, uri, sizeof(s->location));
 160
 161     if (s->headers) {
 162         int len = strlen(s->headers);
 163         if (len < 2 || strcmp("\r\n", s->headers + len - 2))
 164             av_log(h, AV_LOG_ERROR, "No trailing CRLF found in HTTP header.\n");
 165     }
 166
 167     return http_open_cnx(h);
 168 }
 169 static int http_getc(HTTPContext *s)
 170 {
 171     int len;
 172     if (s->buf_ptr >= s->buf_end) {
 173         len = ffurl_read(s->hd, s->buffer, BUFFER_SIZE);
 174         if (len < 0) {
 175             return AVERROR(EIO);
 176         } else if (len == 0) {
 177             return -1;
 178         } else {
 179             s->buf_ptr = s->buffer;
 180             s->buf_end = s->buffer + len;
 181         }
 182     }
 183     return *s->buf_ptr++;
 184 }
 185
 186 static int http_get_line(HTTPContext *s, char *line, int line_size)
 187 {
 188     int ch;
 189     char *q;
 190
 191     q = line;
 192     for(;;) {
 193         ch = http_getc(s);
 194         if (ch < 0)
 195             return AVERROR(EIO);
 196         if (ch == '\n') {
 197             /* process line */
 198             if (q > line && q[-1] == '\r')
 199                 q--;
 200             *q = '\0';
 201
 202             return 0;
 203         } else {
 204             if ((q - line) < line_size - 1)
 205                 *q++ = ch;
 206         }
 207     }
 208 }
 209
 210 static int process_line(URLContext *h, char *line, int line_count,
 211                         int *new_location)
 212 {
 213     HTTPContext *s = h->priv_data;
 214     char *tag, *p, *end;
 215
 216     /* end of header */
 217     if (line[0] == '\0')
 218         return 0;
 219
 220     p = line;
 221     if (line_count == 0) {
 222         while (!isspace(*p) && *p != '\0')
 223             p++;
 224         while (isspace(*p))
 225             p++;
 226         s->http_code = strtol(p, &end, 10);
 227
 228         av_dlog(NULL, "http_code=%d\n", s->http_code);
 229
 230         /* error codes are 4xx and 5xx, but regard 401 as a success, so we
 231          * don't abort until all headers have been parsed. */
 232         if (s->http_code >= 400 && s->http_code < 600 && s->http_code != 401) {
 233             end += strspn(end, SPACE_CHARS);
 234             av_log(h, AV_LOG_WARNING, "HTTP error %d %s\n",
 235                    s->http_code, end);
 236             return -1;
 237         }
 238     } else {
 239         while (*p != '\0' && *p != ':')
 240             p++;
 241         if (*p != ':')
 242             return 1;
 243
 244         *p = '\0';
 245         tag = line;
 246         p++;
 247         while (isspace(*p))
 248             p++;
 249         if (!av_strcasecmp(tag, "Location")) {
 250             strcpy(s->location, p);
 251             *new_location = 1;
 252         } else if (!av_strcasecmp (tag, "Content-Length") && s->filesize == -1) {
 253             s->filesize = atoll(p);
 254         } else if (!av_strcasecmp (tag, "Content-Range")) {
 255             /* "bytes $from-$to/$document_size" */
 256             const char *slash;
 257             if (!strncmp (p, "bytes ", 6)) {
 258                 p += 6;
 259                 s->off = atoll(p);
 260                 if ((slash = strchr(p, '/')) && strlen(slash) > 0)
 261                     s->filesize = atoll(slash+1);
 262             }
 263             h->is_streamed = 0; /* we _can_ in fact seek */
 264         } else if (!av_strcasecmp(tag, "Accept-Ranges") && !strncmp(p, "bytes", 5)) {
 265             h->is_streamed = 0;
 266         } else if (!av_strcasecmp (tag, "Transfer-Encoding") && !av_strncasecmp(p, "chunked", 7)) {
 267             s->filesize = -1;
 268             s->chunksize = 0;
 269         } else if (!av_strcasecmp (tag, "WWW-Authenticate")) {
 270             ff_http_auth_handle_header(&s->auth_state, tag, p);
 271         } else if (!av_strcasecmp (tag, "Authentication-Info")) {
 272             ff_http_auth_handle_header(&s->auth_state, tag, p);
 273         } else if (!av_strcasecmp (tag, "Connection")) {
 274             if (!strcmp(p, "close"))
 275                 s->willclose = 1;
 276         }
 277     }
 278     return 1;
 279 }
 280
 281 static inline int has_header(const char *str, const char *header)
 282 {
 283     /* header + 2 to skip over CRLF prefix. (make sure you have one!) */
 284     if (!str)
 285         return 0;
 286     return av_stristart(str, header + 2, NULL) || av_stristr(str, header);
 287 }
 288
 289 static int http_connect(URLContext *h, const char *path, const char *hoststr,
 290                         const char *auth, int *new_location)
 291 {
 292     HTTPContext *s = h->priv_data;
 293     int post, err;
 294     char line[1024];
 295     char headers[1024] = "";
 296     char *authstr = NULL;
 297     int64_t off = s->off;
 298     int len = 0;
 299
 300
 301     /* send http header */
 302     post = h->flags & AVIO_FLAG_WRITE;
 303     authstr = ff_http_auth_create_response(&s->auth_state, auth, path,
 304                                         post ? "POST" : "GET");
 305
 306     /* set default headers if needed */
 307     if (!has_header(s->headers, "\r\nUser-Agent: "))
 308        len += av_strlcatf(headers + len, sizeof(headers) - len,
 309                           "User-Agent: %s\r\n", LIBAVFORMAT_IDENT);
 310     if (!has_header(s->headers, "\r\nAccept: "))
 311         len += av_strlcpy(headers + len, "Accept: */*\r\n",
 312                           sizeof(headers) - len);
 313     if (!has_header(s->headers, "\r\nRange: "))
 314         len += av_strlcatf(headers + len, sizeof(headers) - len,
 315                            "Range: bytes=%"PRId64"-\r\n", s->off);
 316     if (!has_header(s->headers, "\r\nConnection: "))
 317         len += av_strlcpy(headers + len, "Connection: close\r\n",
 318                           sizeof(headers)-len);
 319     if (!has_header(s->headers, "\r\nHost: "))
 320         len += av_strlcatf(headers + len, sizeof(headers) - len,
 321                            "Host: %s\r\n", hoststr);
 322
 323     /* now add in custom headers */
 324     if (s->headers)
 325         av_strlcpy(headers + len, s->headers, sizeof(headers) - len);
 326
 327     snprintf(s->buffer, sizeof(s->buffer),
 328              "%s %s HTTP/1.1\r\n"
 329              "%s"
 330              "%s"
 331              "%s"
 332              "\r\n",
 333              post ? "POST" : "GET",
 334              path,
 335              post && s->chunksize >= 0 ? "Transfer-Encoding: chunked\r\n" : "",
 336              headers,
 337              authstr ? authstr : "");
 338
 339     av_freep(&authstr);
 340     if (ffurl_write(s->hd, s->buffer, strlen(s->buffer)) < 0)
 341         return AVERROR(EIO);
 342
 343     /* init input buffer */
 344     s->buf_ptr = s->buffer;
 345     s->buf_end = s->buffer;
 346     s->line_count = 0;
 347     s->off = 0;
 348     s->filesize = -1;
 349     s->willclose = 0;
 350     if (post) {
 351         /* Pretend that it did work. We didn't read any header yet, since
 352          * we've still to send the POST data, but the code calling this
 353          * function will check http_code after we return. */
 354         s->http_code = 200;
 355         return 0;
 356     }
 357     s->chunksize = -1;
 358
 359     /* wait for header */
 360     for(;;) {
 361         if (http_get_line(s, line, sizeof(line)) < 0)
 362             return AVERROR(EIO);
 363
 364         av_dlog(NULL, "header='%s'\n", line);
 365
 366         err = process_line(h, line, s->line_count, new_location);
 367         if (err < 0)
 368             return err;
 369         if (err == 0)
 370             break;
 371         s->line_count++;
 372     }
 373
 374     return (off == s->off) ? 0 : -1;
 375 }
 376
 377
 378 static int http_read(URLContext *h, uint8_t *buf, int size)
 379 {
 380     HTTPContext *s = h->priv_data;
 381     int len;
 382
 383     if (s->chunksize >= 0) {
 384         if (!s->chunksize) {
 385             char line[32];
 386
 387             for(;;) {
 388                 do {
 389                     if (http_get_line(s, line, sizeof(line)) < 0)
 390                         return AVERROR(EIO);
 391                 } while (!*line);    /* skip CR LF from last chunk */
 392
 393                 s->chunksize = strtoll(line, NULL, 16);
 394
 395                 av_dlog(NULL, "Chunked encoding data size: %"PRId64"'\n", s->chunksize);
 396
 397                 if (!s->chunksize)
 398                     return 0;
 399                 break;
 400             }
 401         }
 402         size = FFMIN(size, s->chunksize);
 403     }
 404     /* read bytes from input buffer first */
 405     len = s->buf_end - s->buf_ptr;
 406     if (len > 0) {
 407         if (len > size)
 408             len = size;
 409         memcpy(buf, s->buf_ptr, len);
 410         s->buf_ptr += len;
 411     } else {
 412         if (!s->willclose && s->filesize >= 0 && s->off >= s->filesize)
 413             return AVERROR_EOF;
 414         len = ffurl_read(s->hd, buf, size);
 415     }
 416     if (len > 0) {
 417         s->off += len;
 418         if (s->chunksize > 0)
 419             s->chunksize -= len;
 420     }
 421     return len;
 422 }
 423
 424 /* used only when posting data */
 425 static int http_write(URLContext *h, const uint8_t *buf, int size)
 426 {
 427     char temp[11] = "";  /* 32-bit hex + CRLF + nul */
 428     int ret;
 429     char crlf[] = "\r\n";
 430     HTTPContext *s = h->priv_data;
 431
 432     if (s->chunksize == -1) {
 433         /* non-chunked data is sent without any special encoding */
 434         return ffurl_write(s->hd, buf, size);
 435     }
 436
 437     /* silently ignore zero-size data since chunk encoding that would
 438      * signal EOF */
 439     if (size > 0) {
 440         /* upload data using chunked encoding */
 441         snprintf(temp, sizeof(temp), "%x\r\n", size);
 442
 443         if ((ret = ffurl_write(s->hd, temp, strlen(temp))) < 0 ||
 444             (ret = ffurl_write(s->hd, buf, size)) < 0 ||
 445             (ret = ffurl_write(s->hd, crlf, sizeof(crlf) - 1)) < 0)
 446             return ret;
 447     }
 448     return size;
 449 }
 450
 451 static int http_close(URLContext *h)
 452 {
 453     int ret = 0;
 454     char footer[] = "0\r\n\r\n";
 455     HTTPContext *s = h->priv_data;
 456
 457     /* signal end of chunked encoding if used */
 458     if ((h->flags & AVIO_FLAG_WRITE) && s->chunksize != -1) {
 459         ret = ffurl_write(s->hd, footer, sizeof(footer) - 1);
 460         ret = ret > 0 ? 0 : ret;
 461     }
 462
 463     if (s->hd)
 464         ffurl_close(s->hd);
 465     return ret;
 466 }
 467
 468 static int64_t http_seek(URLContext *h, int64_t off, int whence)
 469 {
 470     HTTPContext *s = h->priv_data;
 471     URLContext *old_hd = s->hd;
 472     int64_t old_off = s->off;
 473     uint8_t old_buf[BUFFER_SIZE];
 474     int old_buf_size;
 475
 476     if (whence == AVSEEK_SIZE)
 477         return s->filesize;
 478     else if ((s->filesize == -1 && whence == SEEK_END) || h->is_streamed)
 479         return -1;
 480
 481     /* we save the old context in case the seek fails */
 482     old_buf_size = s->buf_end - s->buf_ptr;
 483     memcpy(old_buf, s->buf_ptr, old_buf_size);
 484     s->hd = NULL;
 485     if (whence == SEEK_CUR)
 486         off += s->off;
 487     else if (whence == SEEK_END)
 488         off += s->filesize;
 489     s->off = off;
 490
 491     /* if it fails, continue on old connection */
 492     if (http_open_cnx(h) < 0) {
 493         memcpy(s->buffer, old_buf, old_buf_size);
 494         s->buf_ptr = s->buffer;
 495         s->buf_end = s->buffer + old_buf_size;
 496         s->hd = old_hd;
 497         s->off = old_off;
 498         return -1;
 499     }
 500     ffurl_close(old_hd);
 501     return off;
 502 }
 503
 504 static int
 505 http_get_file_handle(URLContext *h)
 506 {
 507     HTTPContext *s = h->priv_data;
 508     return ffurl_get_file_handle(s->hd);
 509 }
 510
 511 #if CONFIG_HTTP_PROTOCOL
 512 URLProtocol ff_http_protocol = {
 513     .name                = "http",
 514     .url_open            = http_open,
 515     .url_read            = http_read,
 516     .url_write           = http_write,
 517     .url_seek            = http_seek,
 518     .url_close           = http_close,
 519     .url_get_file_handle = http_get_file_handle,
 520     .priv_data_size      = sizeof(HTTPContext),
 521     .priv_data_class     = &httpcontext_class,
 522 };
 523 #endif
 524 #if CONFIG_HTTPS_PROTOCOL
 525 URLProtocol ff_https_protocol = {
 526     .name                = "https",
 527     .url_open            = http_open,
 528     .url_read            = http_read,
 529     .url_write           = http_write,
 530     .url_seek            = http_seek,
 531     .url_close           = http_close,
 532     .url_get_file_handle = http_get_file_handle,
 533     .priv_data_size      = sizeof(HTTPContext),
 534     .priv_data_class     = &httpcontext_class,
 535 };
 536 #endif