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_set_headers(URLContext *h, const char *headers)
  71 {
  72     HTTPContext *s = h->priv_data;
  73
  74     av_freep(&s->headers);
  75     s->headers = av_strdup(headers);
  76 }
  77
  78 void ff_http_init_auth_state(URLContext *dest, const URLContext *src)
  79 {
  80     memcpy(&((HTTPContext*)dest->priv_data)->auth_state,
  81            &((HTTPContext*)src->priv_data)->auth_state, sizeof(HTTPAuthState));
  82 }
  83
  84 /* return non zero if error */
  85 static int http_open_cnx(URLContext *h)
  86 {
  87     const char *path, *proxy_path, *lower_proto = "tcp";
  88     char hostname[1024], hoststr[1024], proto[10];
  89     char auth[1024];
  90     char path1[1024];
  91     char buf[1024];
  92     int port, use_proxy, err, location_changed = 0, redirects = 0;
  93     HTTPAuthType cur_auth_type;
  94     HTTPContext *s = h->priv_data;
  95     URLContext *hd = NULL;
  96
  97     proxy_path = getenv("http_proxy");
  98     use_proxy = (proxy_path != NULL) && !getenv("no_proxy") &&
  99         av_strstart(proxy_path, "http://", NULL);
 100
 101     /* fill the dest addr */
 102  redo:
 103     /* needed in any case to build the host string */
 104     av_url_split(proto, sizeof(proto), auth, sizeof(auth),
 105                  hostname, sizeof(hostname), &port,
 106                  path1, sizeof(path1), s->location);
 107     ff_url_join(hoststr, sizeof(hoststr), NULL, NULL, hostname, port, NULL);
 108
 109     if (use_proxy) {
 110         av_url_split(NULL, 0, auth, sizeof(auth), hostname, sizeof(hostname), &port,
 111                      NULL, 0, proxy_path);
 112         path = s->location;
 113     } else {
 114         if (path1[0] == '\0')
 115             path = "/";
 116         else
 117             path = path1;
 118     }
 119     if (!strcmp(proto, "https")) {
 120         lower_proto = "tls";
 121         if (port < 0)
 122             port = 443;
 123     }
 124     if (port < 0)
 125         port = 80;
 126
 127     ff_url_join(buf, sizeof(buf), lower_proto, NULL, hostname, port, NULL);
 128     err = ffurl_open(&hd, buf, AVIO_FLAG_READ_WRITE);
 129     if (err < 0)
 130         goto fail;
 131
 132     s->hd = hd;
 133     cur_auth_type = s->auth_state.auth_type;
 134     if (http_connect(h, path, hoststr, auth, &location_changed) < 0)
 135         goto fail;
 136     if (s->http_code == 401) {
 137         if (cur_auth_type == HTTP_AUTH_NONE && s->auth_state.auth_type != HTTP_AUTH_NONE) {
 138             ffurl_close(hd);
 139             goto redo;
 140         } else
 141             goto fail;
 142     }
 143     if ((s->http_code == 301 || s->http_code == 302 || s->http_code == 303 || s->http_code == 307)
 144         && location_changed == 1) {
 145         /* url moved, get next */
 146         ffurl_close(hd);
 147         if (redirects++ >= MAX_REDIRECTS)
 148             return AVERROR(EIO);
 149         location_changed = 0;
 150         goto redo;
 151     }
 152     return 0;
 153  fail:
 154     if (hd)
 155         ffurl_close(hd);
 156     s->hd = NULL;
 157     return AVERROR(EIO);
 158 }
 159
 160 static int http_open(URLContext *h, const char *uri, int flags)
 161 {
 162     HTTPContext *s = h->priv_data;
 163
 164     h->is_streamed = 1;
 165
 166     s->filesize = -1;
 167     av_strlcpy(s->location, uri, sizeof(s->location));
 168
 169     if (s->headers) {
 170         int len = strlen(s->headers);
 171         if (len < 2 || strcmp("\r\n", s->headers + len - 2))
 172             av_log(h, AV_LOG_ERROR, "No trailing CRLF found in HTTP header.\n");
 173     }
 174
 175     return http_open_cnx(h);
 176 }
 177 static int http_getc(HTTPContext *s)
 178 {
 179     int len;
 180     if (s->buf_ptr >= s->buf_end) {
 181         len = ffurl_read(s->hd, s->buffer, BUFFER_SIZE);
 182         if (len < 0) {
 183             return AVERROR(EIO);
 184         } else if (len == 0) {
 185             return -1;
 186         } else {
 187             s->buf_ptr = s->buffer;
 188             s->buf_end = s->buffer + len;
 189         }
 190     }
 191     return *s->buf_ptr++;
 192 }
 193
 194 static int http_get_line(HTTPContext *s, char *line, int line_size)
 195 {
 196     int ch;
 197     char *q;
 198
 199     q = line;
 200     for(;;) {
 201         ch = http_getc(s);
 202         if (ch < 0)
 203             return AVERROR(EIO);
 204         if (ch == '\n') {
 205             /* process line */
 206             if (q > line && q[-1] == '\r')
 207                 q--;
 208             *q = '\0';
 209
 210             return 0;
 211         } else {
 212             if ((q - line) < line_size - 1)
 213                 *q++ = ch;
 214         }
 215     }
 216 }
 217
 218 static int process_line(URLContext *h, char *line, int line_count,
 219                         int *new_location)
 220 {
 221     HTTPContext *s = h->priv_data;
 222     char *tag, *p, *end;
 223
 224     /* end of header */
 225     if (line[0] == '\0')
 226         return 0;
 227
 228     p = line;
 229     if (line_count == 0) {
 230         while (!isspace(*p) && *p != '\0')
 231             p++;
 232         while (isspace(*p))
 233             p++;
 234         s->http_code = strtol(p, &end, 10);
 235
 236         av_dlog(NULL, "http_code=%d\n", s->http_code);
 237
 238         /* error codes are 4xx and 5xx, but regard 401 as a success, so we
 239          * don't abort until all headers have been parsed. */
 240         if (s->http_code >= 400 && s->http_code < 600 && s->http_code != 401) {
 241             end += strspn(end, SPACE_CHARS);
 242             av_log(h, AV_LOG_WARNING, "HTTP error %d %s\n",
 243                    s->http_code, end);
 244             return -1;
 245         }
 246     } else {
 247         while (*p != '\0' && *p != ':')
 248             p++;
 249         if (*p != ':')
 250             return 1;
 251
 252         *p = '\0';
 253         tag = line;
 254         p++;
 255         while (isspace(*p))
 256             p++;
 257         if (!av_strcasecmp(tag, "Location")) {
 258             strcpy(s->location, p);
 259             *new_location = 1;
 260         } else if (!av_strcasecmp (tag, "Content-Length") && s->filesize == -1) {
 261             s->filesize = atoll(p);
 262         } else if (!av_strcasecmp (tag, "Content-Range")) {
 263             /* "bytes $from-$to/$document_size" */
 264             const char *slash;
 265             if (!strncmp (p, "bytes ", 6)) {
 266                 p += 6;
 267                 s->off = atoll(p);
 268                 if ((slash = strchr(p, '/')) && strlen(slash) > 0)
 269                     s->filesize = atoll(slash+1);
 270             }
 271             h->is_streamed = 0; /* we _can_ in fact seek */
 272         } else if (!av_strcasecmp(tag, "Accept-Ranges") && !strncmp(p, "bytes", 5)) {
 273             h->is_streamed = 0;
 274         } else if (!av_strcasecmp (tag, "Transfer-Encoding") && !av_strncasecmp(p, "chunked", 7)) {
 275             s->filesize = -1;
 276             s->chunksize = 0;
 277         } else if (!av_strcasecmp (tag, "WWW-Authenticate")) {
 278             ff_http_auth_handle_header(&s->auth_state, tag, p);
 279         } else if (!av_strcasecmp (tag, "Authentication-Info")) {
 280             ff_http_auth_handle_header(&s->auth_state, tag, p);
 281         } else if (!av_strcasecmp (tag, "Connection")) {
 282             if (!strcmp(p, "close"))
 283                 s->willclose = 1;
 284         }
 285     }
 286     return 1;
 287 }
 288
 289 static inline int has_header(const char *str, const char *header)
 290 {
 291     /* header + 2 to skip over CRLF prefix. (make sure you have one!) */
 292     if (!str)
 293         return 0;
 294     return av_stristart(str, header + 2, NULL) || av_stristr(str, header);
 295 }
 296
 297 static int http_connect(URLContext *h, const char *path, const char *hoststr,
 298                         const char *auth, int *new_location)
 299 {
 300     HTTPContext *s = h->priv_data;
 301     int post, err;
 302     char line[1024];
 303     char headers[1024] = "";
 304     char *authstr = NULL;
 305     int64_t off = s->off;
 306     int len = 0;
 307
 308
 309     /* send http header */
 310     post = h->flags & AVIO_FLAG_WRITE;
 311     authstr = ff_http_auth_create_response(&s->auth_state, auth, path,
 312                                         post ? "POST" : "GET");
 313
 314     /* set default headers if needed */
 315     if (!has_header(s->headers, "\r\nUser-Agent: "))
 316        len += av_strlcatf(headers + len, sizeof(headers) - len,
 317                           "User-Agent: %s\r\n", LIBAVFORMAT_IDENT);
 318     if (!has_header(s->headers, "\r\nAccept: "))
 319         len += av_strlcpy(headers + len, "Accept: */*\r\n",
 320                           sizeof(headers) - len);
 321     if (!has_header(s->headers, "\r\nRange: "))
 322         len += av_strlcatf(headers + len, sizeof(headers) - len,
 323                            "Range: bytes=%"PRId64"-\r\n", s->off);
 324     if (!has_header(s->headers, "\r\nConnection: "))
 325         len += av_strlcpy(headers + len, "Connection: close\r\n",
 326                           sizeof(headers)-len);
 327     if (!has_header(s->headers, "\r\nHost: "))
 328         len += av_strlcatf(headers + len, sizeof(headers) - len,
 329                            "Host: %s\r\n", hoststr);
 330
 331     /* now add in custom headers */
 332     if (s->headers)
 333         av_strlcpy(headers + len, s->headers, sizeof(headers) - len);
 334
 335     snprintf(s->buffer, sizeof(s->buffer),
 336              "%s %s HTTP/1.1\r\n"
 337              "%s"
 338              "%s"
 339              "%s"
 340              "\r\n",
 341              post ? "POST" : "GET",
 342              path,
 343              post && s->chunksize >= 0 ? "Transfer-Encoding: chunked\r\n" : "",
 344              headers,
 345              authstr ? authstr : "");
 346
 347     av_freep(&authstr);
 348     if (ffurl_write(s->hd, s->buffer, strlen(s->buffer)) < 0)
 349         return AVERROR(EIO);
 350
 351     /* init input buffer */
 352     s->buf_ptr = s->buffer;
 353     s->buf_end = s->buffer;
 354     s->line_count = 0;
 355     s->off = 0;
 356     s->filesize = -1;
 357     s->willclose = 0;
 358     if (post) {
 359         /* Pretend that it did work. We didn't read any header yet, since
 360          * we've still to send the POST data, but the code calling this
 361          * function will check http_code after we return. */
 362         s->http_code = 200;
 363         return 0;
 364     }
 365     s->chunksize = -1;
 366
 367     /* wait for header */
 368     for(;;) {
 369         if (http_get_line(s, line, sizeof(line)) < 0)
 370             return AVERROR(EIO);
 371
 372         av_dlog(NULL, "header='%s'\n", line);
 373
 374         err = process_line(h, line, s->line_count, new_location);
 375         if (err < 0)
 376             return err;
 377         if (err == 0)
 378             break;
 379         s->line_count++;
 380     }
 381
 382     return (off == s->off) ? 0 : -1;
 383 }
 384
 385
 386 static int http_read(URLContext *h, uint8_t *buf, int size)
 387 {
 388     HTTPContext *s = h->priv_data;
 389     int len;
 390
 391     if (s->chunksize >= 0) {
 392         if (!s->chunksize) {
 393             char line[32];
 394
 395             for(;;) {
 396                 do {
 397                     if (http_get_line(s, line, sizeof(line)) < 0)
 398                         return AVERROR(EIO);
 399                 } while (!*line);    /* skip CR LF from last chunk */
 400
 401                 s->chunksize = strtoll(line, NULL, 16);
 402
 403                 av_dlog(NULL, "Chunked encoding data size: %"PRId64"'\n", s->chunksize);
 404
 405                 if (!s->chunksize)
 406                     return 0;
 407                 break;
 408             }
 409         }
 410         size = FFMIN(size, s->chunksize);
 411     }
 412     /* read bytes from input buffer first */
 413     len = s->buf_end - s->buf_ptr;
 414     if (len > 0) {
 415         if (len > size)
 416             len = size;
 417         memcpy(buf, s->buf_ptr, len);
 418         s->buf_ptr += len;
 419     } else {
 420         if (!s->willclose && s->filesize >= 0 && s->off >= s->filesize)
 421             return AVERROR_EOF;
 422         len = ffurl_read(s->hd, buf, size);
 423     }
 424     if (len > 0) {
 425         s->off += len;
 426         if (s->chunksize > 0)
 427             s->chunksize -= len;
 428     }
 429     return len;
 430 }
 431
 432 /* used only when posting data */
 433 static int http_write(URLContext *h, const uint8_t *buf, int size)
 434 {
 435     char temp[11] = "";  /* 32-bit hex + CRLF + nul */
 436     int ret;
 437     char crlf[] = "\r\n";
 438     HTTPContext *s = h->priv_data;
 439
 440     if (s->chunksize == -1) {
 441         /* non-chunked data is sent without any special encoding */
 442         return ffurl_write(s->hd, buf, size);
 443     }
 444
 445     /* silently ignore zero-size data since chunk encoding that would
 446      * signal EOF */
 447     if (size > 0) {
 448         /* upload data using chunked encoding */
 449         snprintf(temp, sizeof(temp), "%x\r\n", size);
 450
 451         if ((ret = ffurl_write(s->hd, temp, strlen(temp))) < 0 ||
 452             (ret = ffurl_write(s->hd, buf, size)) < 0 ||
 453             (ret = ffurl_write(s->hd, crlf, sizeof(crlf) - 1)) < 0)
 454             return ret;
 455     }
 456     return size;
 457 }
 458
 459 static int http_close(URLContext *h)
 460 {
 461     int ret = 0;
 462     char footer[] = "0\r\n\r\n";
 463     HTTPContext *s = h->priv_data;
 464
 465     /* signal end of chunked encoding if used */
 466     if ((h->flags & AVIO_FLAG_WRITE) && s->chunksize != -1) {
 467         ret = ffurl_write(s->hd, footer, sizeof(footer) - 1);
 468         ret = ret > 0 ? 0 : ret;
 469     }
 470
 471     if (s->hd)
 472         ffurl_close(s->hd);
 473     return ret;
 474 }
 475
 476 static int64_t http_seek(URLContext *h, int64_t off, int whence)
 477 {
 478     HTTPContext *s = h->priv_data;
 479     URLContext *old_hd = s->hd;
 480     int64_t old_off = s->off;
 481     uint8_t old_buf[BUFFER_SIZE];
 482     int old_buf_size;
 483
 484     if (whence == AVSEEK_SIZE)
 485         return s->filesize;
 486     else if ((s->filesize == -1 && whence == SEEK_END) || h->is_streamed)
 487         return -1;
 488
 489     /* we save the old context in case the seek fails */
 490     old_buf_size = s->buf_end - s->buf_ptr;
 491     memcpy(old_buf, s->buf_ptr, old_buf_size);
 492     s->hd = NULL;
 493     if (whence == SEEK_CUR)
 494         off += s->off;
 495     else if (whence == SEEK_END)
 496         off += s->filesize;
 497     s->off = off;
 498
 499     /* if it fails, continue on old connection */
 500     if (http_open_cnx(h) < 0) {
 501         memcpy(s->buffer, old_buf, old_buf_size);
 502         s->buf_ptr = s->buffer;
 503         s->buf_end = s->buffer + old_buf_size;
 504         s->hd = old_hd;
 505         s->off = old_off;
 506         return -1;
 507     }
 508     ffurl_close(old_hd);
 509     return off;
 510 }
 511
 512 static int
 513 http_get_file_handle(URLContext *h)
 514 {
 515     HTTPContext *s = h->priv_data;
 516     return ffurl_get_file_handle(s->hd);
 517 }
 518
 519 #if CONFIG_HTTP_PROTOCOL
 520 URLProtocol ff_http_protocol = {
 521     .name                = "http",
 522     .url_open            = http_open,
 523     .url_read            = http_read,
 524     .url_write           = http_write,
 525     .url_seek            = http_seek,
 526     .url_close           = http_close,
 527     .url_get_file_handle = http_get_file_handle,
 528     .priv_data_size      = sizeof(HTTPContext),
 529     .priv_data_class     = &httpcontext_class,
 530 };
 531 #endif
 532 #if CONFIG_HTTPS_PROTOCOL
 533 URLProtocol ff_https_protocol = {
 534     .name                = "https",
 535     .url_open            = http_open,
 536     .url_read            = http_read,
 537     .url_write           = http_write,
 538     .url_seek            = http_seek,
 539     .url_close           = http_close,
 540     .url_get_file_handle = http_get_file_handle,
 541     .priv_data_size      = sizeof(HTTPContext),
 542     .priv_data_class     = &httpcontext_class,
 543 };
 544 #endif