block/curl.c

   1 /*
   2  * QEMU Block driver for CURL images
   3  *
   4  * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "qemu-common.h"
  25 #include "block/block_int.h"
  26 #include <curl/curl.h>
  27
  28 // #define DEBUG
  29 // #define DEBUG_VERBOSE
  30
  31 #ifdef DEBUG_CURL
  32 #define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0)
  33 #else
  34 #define DPRINTF(fmt, ...) do { } while (0)
  35 #endif
  36
  37 #if LIBCURL_VERSION_NUM >= 0x071000
  38 /* The multi interface timer callback was introduced in 7.16.0 */
  39 #define NEED_CURL_TIMER_CALLBACK
  40 #endif
  41
  42 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
  43                    CURLPROTO_FTP | CURLPROTO_FTPS | \
  44                    CURLPROTO_TFTP)
  45
  46 #define CURL_NUM_STATES 8
  47 #define CURL_NUM_ACB    8
  48 #define SECTOR_SIZE     512
  49 #define READ_AHEAD_SIZE (256 * 1024)
  50
  51 #define FIND_RET_NONE   0
  52 #define FIND_RET_OK     1
  53 #define FIND_RET_WAIT   2
  54
  55 struct BDRVCURLState;
  56
  57 typedef struct CURLAIOCB {
  58     BlockDriverAIOCB common;
  59     QEMUBH *bh;
  60     QEMUIOVector *qiov;
  61
  62     int64_t sector_num;
  63     int nb_sectors;
  64
  65     size_t start;
  66     size_t end;
  67 } CURLAIOCB;
  68
  69 typedef struct CURLState
  70 {
  71     struct BDRVCURLState *s;
  72     CURLAIOCB *acb[CURL_NUM_ACB];
  73     CURL *curl;
  74     char *orig_buf;
  75     size_t buf_start;
  76     size_t buf_off;
  77     size_t buf_len;
  78     char range[128];
  79     char errmsg[CURL_ERROR_SIZE];
  80     char in_use;
  81 } CURLState;
  82
  83 typedef struct BDRVCURLState {
  84     CURLM *multi;
  85     QEMUTimer timer;
  86     size_t len;
  87     CURLState states[CURL_NUM_STATES];
  88     char *url;
  89     size_t readahead_size;
  90     bool accept_range;
  91 } BDRVCURLState;
  92
  93 static void curl_clean_state(CURLState *s);
  94 static void curl_multi_do(void *arg);
  95
  96 #ifdef NEED_CURL_TIMER_CALLBACK
  97 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
  98 {
  99     BDRVCURLState *s = opaque;
 100
 101     DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
 102     if (timeout_ms == -1) {
 103         timer_del(&s->timer);
 104     } else {
 105         int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
 106         timer_mod(&s->timer,
 107                   qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
 108     }
 109     return 0;
 110 }
 111 #endif
 112
 113 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 114                         void *s, void *sp)
 115 {
 116     DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
 117     switch (action) {
 118         case CURL_POLL_IN:
 119             qemu_aio_set_fd_handler(fd, curl_multi_do, NULL, s);
 120             break;
 121         case CURL_POLL_OUT:
 122             qemu_aio_set_fd_handler(fd, NULL, curl_multi_do, s);
 123             break;
 124         case CURL_POLL_INOUT:
 125             qemu_aio_set_fd_handler(fd, curl_multi_do, curl_multi_do, s);
 126             break;
 127         case CURL_POLL_REMOVE:
 128             qemu_aio_set_fd_handler(fd, NULL, NULL, NULL);
 129             break;
 130     }
 131
 132     return 0;
 133 }
 134
 135 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 136 {
 137     BDRVCURLState *s = opaque;
 138     size_t realsize = size * nmemb;
 139     const char *accept_line = "Accept-Ranges: bytes";
 140
 141     if (realsize >= strlen(accept_line)
 142         && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
 143         s->accept_range = true;
 144     }
 145
 146     return realsize;
 147 }
 148
 149 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 150 {
 151     CURLState *s = ((CURLState*)opaque);
 152     size_t realsize = size * nmemb;
 153     int i;
 154
 155     DPRINTF("CURL: Just reading %zd bytes\n", realsize);
 156
 157     if (!s || !s->orig_buf)
 158         goto read_end;
 159
 160     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
 161     s->buf_off += realsize;
 162
 163     for(i=0; i<CURL_NUM_ACB; i++) {
 164         CURLAIOCB *acb = s->acb[i];
 165
 166         if (!acb)
 167             continue;
 168
 169         if ((s->buf_off >= acb->end)) {
 170             qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
 171                                 acb->end - acb->start);
 172             acb->common.cb(acb->common.opaque, 0);
 173             qemu_aio_release(acb);
 174             s->acb[i] = NULL;
 175         }
 176     }
 177
 178 read_end:
 179     return realsize;
 180 }
 181
 182 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
 183                          CURLAIOCB *acb)
 184 {
 185     int i;
 186     size_t end = start + len;
 187
 188     for (i=0; i<CURL_NUM_STATES; i++) {
 189         CURLState *state = &s->states[i];
 190         size_t buf_end = (state->buf_start + state->buf_off);
 191         size_t buf_fend = (state->buf_start + state->buf_len);
 192
 193         if (!state->orig_buf)
 194             continue;
 195         if (!state->buf_off)
 196             continue;
 197
 198         // Does the existing buffer cover our section?
 199         if ((start >= state->buf_start) &&
 200             (start <= buf_end) &&
 201             (end >= state->buf_start) &&
 202             (end <= buf_end))
 203         {
 204             char *buf = state->orig_buf + (start - state->buf_start);
 205
 206             qemu_iovec_from_buf(acb->qiov, 0, buf, len);
 207             acb->common.cb(acb->common.opaque, 0);
 208
 209             return FIND_RET_OK;
 210         }
 211
 212         // Wait for unfinished chunks
 213         if ((start >= state->buf_start) &&
 214             (start <= buf_fend) &&
 215             (end >= state->buf_start) &&
 216             (end <= buf_fend))
 217         {
 218             int j;
 219
 220             acb->start = start - state->buf_start;
 221             acb->end = acb->start + len;
 222
 223             for (j=0; j<CURL_NUM_ACB; j++) {
 224                 if (!state->acb[j]) {
 225                     state->acb[j] = acb;
 226                     return FIND_RET_WAIT;
 227                 }
 228             }
 229         }
 230     }
 231
 232     return FIND_RET_NONE;
 233 }
 234
 235 static void curl_multi_read(BDRVCURLState *s)
 236 {
 237     int msgs_in_queue;
 238
 239     /* Try to find done transfers, so we can free the easy
 240      * handle again. */
 241     do {
 242         CURLMsg *msg;
 243         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 244
 245         if (!msg)
 246             break;
 247         if (msg->msg == CURLMSG_NONE)
 248             break;
 249
 250         switch (msg->msg) {
 251             case CURLMSG_DONE:
 252             {
 253                 CURLState *state = NULL;
 254                 curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE, (char**)&state);
 255
 256                 /* ACBs for successful messages get completed in curl_read_cb */
 257                 if (msg->data.result != CURLE_OK) {
 258                     int i;
 259                     for (i = 0; i < CURL_NUM_ACB; i++) {
 260                         CURLAIOCB *acb = state->acb[i];
 261
 262                         if (acb == NULL) {
 263                             continue;
 264                         }
 265
 266                         acb->common.cb(acb->common.opaque, -EIO);
 267                         qemu_aio_release(acb);
 268                         state->acb[i] = NULL;
 269                     }
 270                 }
 271
 272                 curl_clean_state(state);
 273                 break;
 274             }
 275             default:
 276                 msgs_in_queue = 0;
 277                 break;
 278         }
 279     } while(msgs_in_queue);
 280 }
 281
 282 static void curl_multi_do(void *arg)
 283 {
 284     BDRVCURLState *s = (BDRVCURLState *)arg;
 285     int running;
 286     int r;
 287
 288     if (!s->multi) {
 289         return;
 290     }
 291
 292     do {
 293         r = curl_multi_socket_all(s->multi, &running);
 294     } while(r == CURLM_CALL_MULTI_PERFORM);
 295
 296     curl_multi_read(s);
 297 }
 298
 299 static void curl_multi_timeout_do(void *arg)
 300 {
 301 #ifdef NEED_CURL_TIMER_CALLBACK
 302     BDRVCURLState *s = (BDRVCURLState *)arg;
 303     int running;
 304
 305     if (!s->multi) {
 306         return;
 307     }
 308
 309     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 310
 311     curl_multi_read(s);
 312 #else
 313     abort();
 314 #endif
 315 }
 316
 317 static CURLState *curl_init_state(BDRVCURLState *s)
 318 {
 319     CURLState *state = NULL;
 320     int i, j;
 321
 322     do {
 323         for (i=0; i<CURL_NUM_STATES; i++) {
 324             for (j=0; j<CURL_NUM_ACB; j++)
 325                 if (s->states[i].acb[j])
 326                     continue;
 327             if (s->states[i].in_use)
 328                 continue;
 329
 330             state = &s->states[i];
 331             state->in_use = 1;
 332             break;
 333         }
 334         if (!state) {
 335             g_usleep(100);
 336             curl_multi_do(s);
 337         }
 338     } while(!state);
 339
 340     if (state->curl)
 341         goto has_curl;
 342
 343     state->curl = curl_easy_init();
 344     if (!state->curl)
 345         return NULL;
 346     curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
 347     curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, 5);
 348     curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
 349     curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
 350     curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
 351     curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
 352     curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
 353     curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
 354     curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
 355     curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 356
 357     /* Restrict supported protocols to avoid security issues in the more
 358      * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
 359      * CVE-2013-0249.
 360      *
 361      * Restricting protocols is only supported from 7.19.4 upwards.
 362      */
 363 #if LIBCURL_VERSION_NUM >= 0x071304
 364     curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
 365     curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
 366 #endif
 367
 368 #ifdef DEBUG_VERBOSE
 369     curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
 370 #endif
 371
 372 has_curl:
 373
 374     state->s = s;
 375
 376     return state;
 377 }
 378
 379 static void curl_clean_state(CURLState *s)
 380 {
 381     if (s->s->multi)
 382         curl_multi_remove_handle(s->s->multi, s->curl);
 383     s->in_use = 0;
 384 }
 385
 386 static void curl_parse_filename(const char *filename, QDict *options,
 387                                 Error **errp)
 388 {
 389
 390     #define RA_OPTSTR ":readahead="
 391     char *file;
 392     char *ra;
 393     const char *ra_val;
 394     int parse_state = 0;
 395
 396     file = g_strdup(filename);
 397
 398     /* Parse a trailing ":readahead=#:" param, if present. */
 399     ra = file + strlen(file) - 1;
 400     while (ra >= file) {
 401         if (parse_state == 0) {
 402             if (*ra == ':') {
 403                 parse_state++;
 404             } else {
 405                 break;
 406             }
 407         } else if (parse_state == 1) {
 408             if (*ra > '9' || *ra < '0') {
 409                 char *opt_start = ra - strlen(RA_OPTSTR) + 1;
 410                 if (opt_start > file &&
 411                     strncmp(opt_start, RA_OPTSTR, strlen(RA_OPTSTR)) == 0) {
 412                     ra_val = ra + 1;
 413                     ra -= strlen(RA_OPTSTR) - 1;
 414                     *ra = '\0';
 415                     qdict_put(options, "readahead", qstring_from_str(ra_val));
 416                 }
 417                 break;
 418             }
 419         }
 420         ra--;
 421     }
 422
 423     qdict_put(options, "url", qstring_from_str(file));
 424
 425     g_free(file);
 426 }
 427
 428 static QemuOptsList runtime_opts = {
 429     .name = "curl",
 430     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 431     .desc = {
 432         {
 433             .name = "url",
 434             .type = QEMU_OPT_STRING,
 435             .help = "URL to open",
 436         },
 437         {
 438             .name = "readahead",
 439             .type = QEMU_OPT_SIZE,
 440             .help = "Readahead size",
 441         },
 442         { /* end of list */ }
 443     },
 444 };
 445
 446 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 447                      Error **errp)
 448 {
 449     BDRVCURLState *s = bs->opaque;
 450     CURLState *state = NULL;
 451     QemuOpts *opts;
 452     Error *local_err = NULL;
 453     const char *file;
 454     double d;
 455
 456     static int inited = 0;
 457
 458     if (flags & BDRV_O_RDWR) {
 459         qerror_report(ERROR_CLASS_GENERIC_ERROR,
 460                       "curl block device does not support writes");
 461         return -EROFS;
 462     }
 463
 464     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 465     qemu_opts_absorb_qdict(opts, options, &local_err);
 466     if (local_err) {
 467         qerror_report_err(local_err);
 468         error_free(local_err);
 469         goto out_noclean;
 470     }
 471
 472     s->readahead_size = qemu_opt_get_size(opts, "readahead", READ_AHEAD_SIZE);
 473     if ((s->readahead_size & 0x1ff) != 0) {
 474         fprintf(stderr, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512\n",
 475                 s->readahead_size);
 476         goto out_noclean;
 477     }
 478
 479     file = qemu_opt_get(opts, "url");
 480     if (file == NULL) {
 481         qerror_report(ERROR_CLASS_GENERIC_ERROR, "curl block driver requires "
 482                       "an 'url' option");
 483         goto out_noclean;
 484     }
 485
 486     if (!inited) {
 487         curl_global_init(CURL_GLOBAL_ALL);
 488         inited = 1;
 489     }
 490
 491     DPRINTF("CURL: Opening %s\n", file);
 492     s->url = g_strdup(file);
 493     state = curl_init_state(s);
 494     if (!state)
 495         goto out_noclean;
 496
 497     // Get file size
 498
 499     s->accept_range = false;
 500     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
 501     curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
 502                      curl_header_cb);
 503     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
 504     if (curl_easy_perform(state->curl))
 505         goto out;
 506     curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
 507     if (d)
 508         s->len = (size_t)d;
 509     else if(!s->len)
 510         goto out;
 511     if ((!strncasecmp(s->url, "http://", strlen("http://"))
 512         || !strncasecmp(s->url, "https://", strlen("https://")))
 513         && !s->accept_range) {
 514         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 515                 "Server does not support 'range' (byte ranges).");
 516         goto out;
 517     }
 518     DPRINTF("CURL: Size = %zd\n", s->len);
 519
 520     curl_clean_state(state);
 521     curl_easy_cleanup(state->curl);
 522     state->curl = NULL;
 523
 524     aio_timer_init(bdrv_get_aio_context(bs), &s->timer,
 525                    QEMU_CLOCK_REALTIME, SCALE_NS,
 526                    curl_multi_timeout_do, s);
 527
 528     // Now we know the file exists and its size, so let's
 529     // initialize the multi interface!
 530
 531     s->multi = curl_multi_init();
 532     curl_multi_setopt(s->multi, CURLMOPT_SOCKETDATA, s);
 533     curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
 534 #ifdef NEED_CURL_TIMER_CALLBACK
 535     curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
 536     curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
 537 #endif
 538     curl_multi_do(s);
 539
 540     qemu_opts_del(opts);
 541     return 0;
 542
 543 out:
 544     fprintf(stderr, "CURL: Error opening file: %s\n", state->errmsg);
 545     curl_easy_cleanup(state->curl);
 546     state->curl = NULL;
 547 out_noclean:
 548     g_free(s->url);
 549     qemu_opts_del(opts);
 550     return -EINVAL;
 551 }
 552
 553 static void curl_aio_cancel(BlockDriverAIOCB *blockacb)
 554 {
 555     // Do we have to implement canceling? Seems to work without...
 556 }
 557
 558 static const AIOCBInfo curl_aiocb_info = {
 559     .aiocb_size         = sizeof(CURLAIOCB),
 560     .cancel             = curl_aio_cancel,
 561 };
 562
 563
 564 static void curl_readv_bh_cb(void *p)
 565 {
 566     CURLState *state;
 567
 568     CURLAIOCB *acb = p;
 569     BDRVCURLState *s = acb->common.bs->opaque;
 570
 571     qemu_bh_delete(acb->bh);
 572     acb->bh = NULL;
 573
 574     size_t start = acb->sector_num * SECTOR_SIZE;
 575     size_t end;
 576
 577     // In case we have the requested data already (e.g. read-ahead),
 578     // we can just call the callback and be done.
 579     switch (curl_find_buf(s, start, acb->nb_sectors * SECTOR_SIZE, acb)) {
 580         case FIND_RET_OK:
 581             qemu_aio_release(acb);
 582             // fall through
 583         case FIND_RET_WAIT:
 584             return;
 585         default:
 586             break;
 587     }
 588
 589     // No cache found, so let's start a new request
 590     state = curl_init_state(s);
 591     if (!state) {
 592         acb->common.cb(acb->common.opaque, -EIO);
 593         qemu_aio_release(acb);
 594         return;
 595     }
 596
 597     acb->start = 0;
 598     acb->end = (acb->nb_sectors * SECTOR_SIZE);
 599
 600     state->buf_off = 0;
 601     if (state->orig_buf)
 602         g_free(state->orig_buf);
 603     state->buf_start = start;
 604     state->buf_len = acb->end + s->readahead_size;
 605     end = MIN(start + state->buf_len, s->len) - 1;
 606     state->orig_buf = g_malloc(state->buf_len);
 607     state->acb[0] = acb;
 608
 609     snprintf(state->range, 127, "%zd-%zd", start, end);
 610     DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
 611             (acb->nb_sectors * SECTOR_SIZE), start, state->range);
 612     curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
 613
 614     curl_multi_add_handle(s->multi, state->curl);
 615     curl_multi_do(s);
 616
 617 }
 618
 619 static BlockDriverAIOCB *curl_aio_readv(BlockDriverState *bs,
 620         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 621         BlockDriverCompletionFunc *cb, void *opaque)
 622 {
 623     CURLAIOCB *acb;
 624
 625     acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
 626
 627     acb->qiov = qiov;
 628     acb->sector_num = sector_num;
 629     acb->nb_sectors = nb_sectors;
 630
 631     acb->bh = qemu_bh_new(curl_readv_bh_cb, acb);
 632     qemu_bh_schedule(acb->bh);
 633     return &acb->common;
 634 }
 635
 636 static void curl_close(BlockDriverState *bs)
 637 {
 638     BDRVCURLState *s = bs->opaque;
 639     int i;
 640
 641     DPRINTF("CURL: Close\n");
 642     for (i=0; i<CURL_NUM_STATES; i++) {
 643         if (s->states[i].in_use)
 644             curl_clean_state(&s->states[i]);
 645         if (s->states[i].curl) {
 646             curl_easy_cleanup(s->states[i].curl);
 647             s->states[i].curl = NULL;
 648         }
 649         if (s->states[i].orig_buf) {
 650             g_free(s->states[i].orig_buf);
 651             s->states[i].orig_buf = NULL;
 652         }
 653     }
 654     if (s->multi)
 655         curl_multi_cleanup(s->multi);
 656
 657     timer_del(&s->timer);
 658
 659     g_free(s->url);
 660 }
 661
 662 static int64_t curl_getlength(BlockDriverState *bs)
 663 {
 664     BDRVCURLState *s = bs->opaque;
 665     return s->len;
 666 }
 667
 668 static BlockDriver bdrv_http = {
 669     .format_name            = "http",
 670     .protocol_name          = "http",
 671
 672     .instance_size          = sizeof(BDRVCURLState),
 673     .bdrv_parse_filename    = curl_parse_filename,
 674     .bdrv_file_open         = curl_open,
 675     .bdrv_close             = curl_close,
 676     .bdrv_getlength         = curl_getlength,
 677
 678     .bdrv_aio_readv         = curl_aio_readv,
 679 };
 680
 681 static BlockDriver bdrv_https = {
 682     .format_name            = "https",
 683     .protocol_name          = "https",
 684
 685     .instance_size          = sizeof(BDRVCURLState),
 686     .bdrv_parse_filename    = curl_parse_filename,
 687     .bdrv_file_open         = curl_open,
 688     .bdrv_close             = curl_close,
 689     .bdrv_getlength         = curl_getlength,
 690
 691     .bdrv_aio_readv         = curl_aio_readv,
 692 };
 693
 694 static BlockDriver bdrv_ftp = {
 695     .format_name            = "ftp",
 696     .protocol_name          = "ftp",
 697
 698     .instance_size          = sizeof(BDRVCURLState),
 699     .bdrv_parse_filename    = curl_parse_filename,
 700     .bdrv_file_open         = curl_open,
 701     .bdrv_close             = curl_close,
 702     .bdrv_getlength         = curl_getlength,
 703
 704     .bdrv_aio_readv         = curl_aio_readv,
 705 };
 706
 707 static BlockDriver bdrv_ftps = {
 708     .format_name            = "ftps",
 709     .protocol_name          = "ftps",
 710
 711     .instance_size          = sizeof(BDRVCURLState),
 712     .bdrv_parse_filename    = curl_parse_filename,
 713     .bdrv_file_open         = curl_open,
 714     .bdrv_close             = curl_close,
 715     .bdrv_getlength         = curl_getlength,
 716
 717     .bdrv_aio_readv         = curl_aio_readv,
 718 };
 719
 720 static BlockDriver bdrv_tftp = {
 721     .format_name            = "tftp",
 722     .protocol_name          = "tftp",
 723
 724     .instance_size          = sizeof(BDRVCURLState),
 725     .bdrv_parse_filename    = curl_parse_filename,
 726     .bdrv_file_open         = curl_open,
 727     .bdrv_close             = curl_close,
 728     .bdrv_getlength         = curl_getlength,
 729
 730     .bdrv_aio_readv         = curl_aio_readv,
 731 };
 732
 733 static void curl_block_init(void)
 734 {
 735     bdrv_register(&bdrv_http);
 736     bdrv_register(&bdrv_https);
 737     bdrv_register(&bdrv_ftp);
 738     bdrv_register(&bdrv_ftps);
 739     bdrv_register(&bdrv_tftp);
 740 }
 741
 742 block_init(curl_block_init);