Libav
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00001 /* 00002 * HTTP protocol for ffmpeg client 00003 * Copyright (c) 2000, 2001 Fabrice Bellard 00004 * 00005 * This file is part of FFmpeg. 00006 * 00007 * FFmpeg is free software; you can redistribute it and/or 00008 * modify it under the terms of the GNU Lesser General Public 00009 * License as published by the Free Software Foundation; either 00010 * version 2.1 of the License, or (at your option) any later version. 00011 * 00012 * FFmpeg is distributed in the hope that it will be useful, 00013 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 00015 * Lesser General Public License for more details. 00016 * 00017 * You should have received a copy of the GNU Lesser General Public 00018 * License along with FFmpeg; if not, write to the Free Software 00019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 00020 */ 00021 00022 #include "libavutil/avstring.h" 00023 #include "avformat.h" 00024 #include <unistd.h> 00025 #include <strings.h> 00026 #include "internal.h" 00027 #include "network.h" 00028 #include "os_support.h" 00029 #include "httpauth.h" 00030 00031 /* XXX: POST protocol is not completely implemented because ffmpeg uses 00032 only a subset of it. */ 00033 00034 /* used for protocol handling */ 00035 #define BUFFER_SIZE 1024 00036 #define URL_SIZE 4096 00037 #define MAX_REDIRECTS 8 00038 00039 typedef struct { 00040 URLContext *hd; 00041 unsigned char buffer[BUFFER_SIZE], *buf_ptr, *buf_end; 00042 int line_count; 00043 int http_code; 00044 int64_t chunksize; 00045 int64_t off, filesize; 00046 char location[URL_SIZE]; 00047 HTTPAuthState auth_state; 00048 } HTTPContext; 00049 00050 static int http_connect(URLContext *h, const char *path, const char *hoststr, 00051 const char *auth, int *new_location); 00052 static int http_write(URLContext *h, uint8_t *buf, int size); 00053 00054 00055 /* return non zero if error */ 00056 static int http_open_cnx(URLContext *h) 00057 { 00058 const char *path, *proxy_path; 00059 char hostname[1024], hoststr[1024]; 00060 char auth[1024]; 00061 char path1[1024]; 00062 char buf[1024]; 00063 int port, use_proxy, err, location_changed = 0, redirects = 0; 00064 HTTPAuthType cur_auth_type; 00065 HTTPContext *s = h->priv_data; 00066 URLContext *hd = NULL; 00067 00068 proxy_path = getenv("http_proxy"); 00069 use_proxy = (proxy_path != NULL) && !getenv("no_proxy") && 00070 av_strstart(proxy_path, "http://", NULL); 00071 00072 /* fill the dest addr */ 00073 redo: 00074 /* needed in any case to build the host string */ 00075 ff_url_split(NULL, 0, auth, sizeof(auth), hostname, sizeof(hostname), &port, 00076 path1, sizeof(path1), s->location); 00077 ff_url_join(hoststr, sizeof(hoststr), NULL, NULL, hostname, port, NULL); 00078 00079 if (use_proxy) { 00080 ff_url_split(NULL, 0, auth, sizeof(auth), hostname, sizeof(hostname), &port, 00081 NULL, 0, proxy_path); 00082 path = s->location; 00083 } else { 00084 if (path1[0] == '\0') 00085 path = "/"; 00086 else 00087 path = path1; 00088 } 00089 if (port < 0) 00090 port = 80; 00091 00092 ff_url_join(buf, sizeof(buf), "tcp", NULL, hostname, port, NULL); 00093 err = url_open(&hd, buf, URL_RDWR); 00094 if (err < 0) 00095 goto fail; 00096 00097 s->hd = hd; 00098 cur_auth_type = s->auth_state.auth_type; 00099 if (http_connect(h, path, hoststr, auth, &location_changed) < 0) 00100 goto fail; 00101 if (s->http_code == 401) { 00102 if (cur_auth_type == HTTP_AUTH_NONE && s->auth_state.auth_type != HTTP_AUTH_NONE) { 00103 url_close(hd); 00104 goto redo; 00105 } else 00106 goto fail; 00107 } 00108 if ((s->http_code == 302 || s->http_code == 303) && location_changed == 1) { 00109 /* url moved, get next */ 00110 url_close(hd); 00111 if (redirects++ >= MAX_REDIRECTS) 00112 return AVERROR(EIO); 00113 location_changed = 0; 00114 goto redo; 00115 } 00116 return 0; 00117 fail: 00118 if (hd) 00119 url_close(hd); 00120 return AVERROR(EIO); 00121 } 00122 00123 static int http_open(URLContext *h, const char *uri, int flags) 00124 { 00125 HTTPContext *s; 00126 int ret; 00127 00128 h->is_streamed = 1; 00129 00130 s = av_malloc(sizeof(HTTPContext)); 00131 if (!s) { 00132 return AVERROR(ENOMEM); 00133 } 00134 h->priv_data = s; 00135 s->filesize = -1; 00136 s->chunksize = -1; 00137 s->off = 0; 00138 memset(&s->auth_state, 0, sizeof(s->auth_state)); 00139 av_strlcpy(s->location, uri, URL_SIZE); 00140 00141 ret = http_open_cnx(h); 00142 if (ret != 0) 00143 av_free (s); 00144 return ret; 00145 } 00146 static int http_getc(HTTPContext *s) 00147 { 00148 int len; 00149 if (s->buf_ptr >= s->buf_end) { 00150 len = url_read(s->hd, s->buffer, BUFFER_SIZE); 00151 if (len < 0) { 00152 return AVERROR(EIO); 00153 } else if (len == 0) { 00154 return -1; 00155 } else { 00156 s->buf_ptr = s->buffer; 00157 s->buf_end = s->buffer + len; 00158 } 00159 } 00160 return *s->buf_ptr++; 00161 } 00162 00163 static int http_get_line(HTTPContext *s, char *line, int line_size) 00164 { 00165 int ch; 00166 char *q; 00167 00168 q = line; 00169 for(;;) { 00170 ch = http_getc(s); 00171 if (ch < 0) 00172 return AVERROR(EIO); 00173 if (ch == '\n') { 00174 /* process line */ 00175 if (q > line && q[-1] == '\r') 00176 q--; 00177 *q = '\0'; 00178 00179 return 0; 00180 } else { 00181 if ((q - line) < line_size - 1) 00182 *q++ = ch; 00183 } 00184 } 00185 } 00186 00187 static int process_line(URLContext *h, char *line, int line_count, 00188 int *new_location) 00189 { 00190 HTTPContext *s = h->priv_data; 00191 char *tag, *p; 00192 00193 /* end of header */ 00194 if (line[0] == '\0') 00195 return 0; 00196 00197 p = line; 00198 if (line_count == 0) { 00199 while (!isspace(*p) && *p != '\0') 00200 p++; 00201 while (isspace(*p)) 00202 p++; 00203 s->http_code = strtol(p, NULL, 10); 00204 00205 dprintf(NULL, "http_code=%d\n", s->http_code); 00206 00207 /* error codes are 4xx and 5xx, but regard 401 as a success, so we 00208 * don't abort until all headers have been parsed. */ 00209 if (s->http_code >= 400 && s->http_code < 600 && s->http_code != 401) 00210 return -1; 00211 } else { 00212 while (*p != '\0' && *p != ':') 00213 p++; 00214 if (*p != ':') 00215 return 1; 00216 00217 *p = '\0'; 00218 tag = line; 00219 p++; 00220 while (isspace(*p)) 00221 p++; 00222 if (!strcmp(tag, "Location")) { 00223 strcpy(s->location, p); 00224 *new_location = 1; 00225 } else if (!strcmp (tag, "Content-Length") && s->filesize == -1) { 00226 s->filesize = atoll(p); 00227 } else if (!strcmp (tag, "Content-Range")) { 00228 /* "bytes $from-$to/$document_size" */ 00229 const char *slash; 00230 if (!strncmp (p, "bytes ", 6)) { 00231 p += 6; 00232 s->off = atoll(p); 00233 if ((slash = strchr(p, '/')) && strlen(slash) > 0) 00234 s->filesize = atoll(slash+1); 00235 } 00236 h->is_streamed = 0; /* we _can_ in fact seek */ 00237 } else if (!strcmp (tag, "Transfer-Encoding") && !strncasecmp(p, "chunked", 7)) { 00238 s->filesize = -1; 00239 s->chunksize = 0; 00240 } else if (!strcmp (tag, "WWW-Authenticate")) { 00241 ff_http_auth_handle_header(&s->auth_state, tag, p); 00242 } else if (!strcmp (tag, "Authentication-Info")) { 00243 ff_http_auth_handle_header(&s->auth_state, tag, p); 00244 } 00245 } 00246 return 1; 00247 } 00248 00249 static int http_connect(URLContext *h, const char *path, const char *hoststr, 00250 const char *auth, int *new_location) 00251 { 00252 HTTPContext *s = h->priv_data; 00253 int post, err; 00254 char line[1024]; 00255 char *authstr = NULL; 00256 int64_t off = s->off; 00257 00258 00259 /* send http header */ 00260 post = h->flags & URL_WRONLY; 00261 authstr = ff_http_auth_create_response(&s->auth_state, auth, path, 00262 post ? "POST" : "GET"); 00263 snprintf(s->buffer, sizeof(s->buffer), 00264 "%s %s HTTP/1.1\r\n" 00265 "User-Agent: %s\r\n" 00266 "Accept: */*\r\n" 00267 "Range: bytes=%"PRId64"-\r\n" 00268 "Host: %s\r\n" 00269 "%s" 00270 "Connection: close\r\n" 00271 "%s" 00272 "\r\n", 00273 post ? "POST" : "GET", 00274 path, 00275 LIBAVFORMAT_IDENT, 00276 s->off, 00277 hoststr, 00278 authstr ? authstr : "", 00279 post ? "Transfer-Encoding: chunked\r\n" : ""); 00280 00281 av_freep(&authstr); 00282 if (http_write(h, s->buffer, strlen(s->buffer)) < 0) 00283 return AVERROR(EIO); 00284 00285 /* init input buffer */ 00286 s->buf_ptr = s->buffer; 00287 s->buf_end = s->buffer; 00288 s->line_count = 0; 00289 s->off = 0; 00290 s->filesize = -1; 00291 if (post) { 00292 /* always use chunked encoding for upload data */ 00293 s->chunksize = 0; 00294 return 0; 00295 } 00296 00297 /* wait for header */ 00298 for(;;) { 00299 if (http_get_line(s, line, sizeof(line)) < 0) 00300 return AVERROR(EIO); 00301 00302 dprintf(NULL, "header='%s'\n", line); 00303 00304 err = process_line(h, line, s->line_count, new_location); 00305 if (err < 0) 00306 return err; 00307 if (err == 0) 00308 break; 00309 s->line_count++; 00310 } 00311 00312 return (off == s->off) ? 0 : -1; 00313 } 00314 00315 00316 static int http_read(URLContext *h, uint8_t *buf, int size) 00317 { 00318 HTTPContext *s = h->priv_data; 00319 int len; 00320 00321 if (s->chunksize >= 0) { 00322 if (!s->chunksize) { 00323 char line[32]; 00324 00325 for(;;) { 00326 do { 00327 if (http_get_line(s, line, sizeof(line)) < 0) 00328 return AVERROR(EIO); 00329 } while (!*line); /* skip CR LF from last chunk */ 00330 00331 s->chunksize = strtoll(line, NULL, 16); 00332 00333 dprintf(NULL, "Chunked encoding data size: %"PRId64"'\n", s->chunksize); 00334 00335 if (!s->chunksize) 00336 return 0; 00337 break; 00338 } 00339 } 00340 size = FFMIN(size, s->chunksize); 00341 } 00342 /* read bytes from input buffer first */ 00343 len = s->buf_end - s->buf_ptr; 00344 if (len > 0) { 00345 if (len > size) 00346 len = size; 00347 memcpy(buf, s->buf_ptr, len); 00348 s->buf_ptr += len; 00349 } else { 00350 len = url_read(s->hd, buf, size); 00351 } 00352 if (len > 0) { 00353 s->off += len; 00354 if (s->chunksize > 0) 00355 s->chunksize -= len; 00356 } 00357 return len; 00358 } 00359 00360 /* used only when posting data */ 00361 static int http_write(URLContext *h, uint8_t *buf, int size) 00362 { 00363 char temp[11]; /* 32-bit hex + CRLF + nul */ 00364 int ret; 00365 char crlf[] = "\r\n"; 00366 HTTPContext *s = h->priv_data; 00367 00368 if (s->chunksize == -1) { 00369 /* headers are sent without any special encoding */ 00370 return url_write(s->hd, buf, size); 00371 } 00372 00373 /* silently ignore zero-size data since chunk encoding that would 00374 * signal EOF */ 00375 if (size > 0) { 00376 /* upload data using chunked encoding */ 00377 snprintf(temp, sizeof(temp), "%x\r\n", size); 00378 00379 if ((ret = url_write(s->hd, temp, strlen(temp))) < 0 || 00380 (ret = url_write(s->hd, buf, size)) < 0 || 00381 (ret = url_write(s->hd, crlf, sizeof(crlf) - 1)) < 0) 00382 return ret; 00383 } 00384 return size; 00385 } 00386 00387 static int http_close(URLContext *h) 00388 { 00389 int ret = 0; 00390 char footer[] = "0\r\n\r\n"; 00391 HTTPContext *s = h->priv_data; 00392 00393 /* signal end of chunked encoding if used */ 00394 if ((h->flags & URL_WRONLY) && s->chunksize != -1) { 00395 ret = url_write(s->hd, footer, sizeof(footer) - 1); 00396 ret = ret > 0 ? 0 : ret; 00397 } 00398 00399 url_close(s->hd); 00400 av_free(s); 00401 return ret; 00402 } 00403 00404 static int64_t http_seek(URLContext *h, int64_t off, int whence) 00405 { 00406 HTTPContext *s = h->priv_data; 00407 URLContext *old_hd = s->hd; 00408 int64_t old_off = s->off; 00409 uint8_t old_buf[BUFFER_SIZE]; 00410 int old_buf_size; 00411 00412 if (whence == AVSEEK_SIZE) 00413 return s->filesize; 00414 else if ((s->filesize == -1 && whence == SEEK_END) || h->is_streamed) 00415 return -1; 00416 00417 /* we save the old context in case the seek fails */ 00418 old_buf_size = s->buf_end - s->buf_ptr; 00419 memcpy(old_buf, s->buf_ptr, old_buf_size); 00420 s->hd = NULL; 00421 if (whence == SEEK_CUR) 00422 off += s->off; 00423 else if (whence == SEEK_END) 00424 off += s->filesize; 00425 s->off = off; 00426 00427 /* if it fails, continue on old connection */ 00428 if (http_open_cnx(h) < 0) { 00429 memcpy(s->buffer, old_buf, old_buf_size); 00430 s->buf_ptr = s->buffer; 00431 s->buf_end = s->buffer + old_buf_size; 00432 s->hd = old_hd; 00433 s->off = old_off; 00434 return -1; 00435 } 00436 url_close(old_hd); 00437 return off; 00438 } 00439 00440 static int 00441 http_get_file_handle(URLContext *h) 00442 { 00443 HTTPContext *s = h->priv_data; 00444 return url_get_file_handle(s->hd); 00445 } 00446 00447 URLProtocol http_protocol = { 00448 "http", 00449 http_open, 00450 http_read, 00451 http_write, 00452 http_seek, 00453 http_close, 00454 .url_get_file_handle = http_get_file_handle, 00455 };