Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
[qemu.git] / 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 error_setg(errp, "curl block device does not support writes");
460 return -EROFS;
461 }
462
463 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
464 qemu_opts_absorb_qdict(opts, options, &local_err);
465 if (local_err) {
466 error_propagate(errp, local_err);
467 goto out_noclean;
468 }
469
470 s->readahead_size = qemu_opt_get_size(opts, "readahead", READ_AHEAD_SIZE);
471 if ((s->readahead_size & 0x1ff) != 0) {
472 error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
473 s->readahead_size);
474 goto out_noclean;
475 }
476
477 file = qemu_opt_get(opts, "url");
478 if (file == NULL) {
479 error_setg(errp, "curl block driver requires an 'url' option");
480 goto out_noclean;
481 }
482
483 if (!inited) {
484 curl_global_init(CURL_GLOBAL_ALL);
485 inited = 1;
486 }
487
488 DPRINTF("CURL: Opening %s\n", file);
489 s->url = g_strdup(file);
490 state = curl_init_state(s);
491 if (!state)
492 goto out_noclean;
493
494 // Get file size
495
496 s->accept_range = false;
497 curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
498 curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
499 curl_header_cb);
500 curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
501 if (curl_easy_perform(state->curl))
502 goto out;
503 curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
504 if (d)
505 s->len = (size_t)d;
506 else if(!s->len)
507 goto out;
508 if ((!strncasecmp(s->url, "http://", strlen("http://"))
509 || !strncasecmp(s->url, "https://", strlen("https://")))
510 && !s->accept_range) {
511 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
512 "Server does not support 'range' (byte ranges).");
513 goto out;
514 }
515 DPRINTF("CURL: Size = %zd\n", s->len);
516
517 curl_clean_state(state);
518 curl_easy_cleanup(state->curl);
519 state->curl = NULL;
520
521 aio_timer_init(bdrv_get_aio_context(bs), &s->timer,
522 QEMU_CLOCK_REALTIME, SCALE_NS,
523 curl_multi_timeout_do, s);
524
525 // Now we know the file exists and its size, so let's
526 // initialize the multi interface!
527
528 s->multi = curl_multi_init();
529 curl_multi_setopt(s->multi, CURLMOPT_SOCKETDATA, s);
530 curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
531 #ifdef NEED_CURL_TIMER_CALLBACK
532 curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
533 curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
534 #endif
535 curl_multi_do(s);
536
537 qemu_opts_del(opts);
538 return 0;
539
540 out:
541 fprintf(stderr, "CURL: Error opening file: %s\n", state->errmsg);
542 curl_easy_cleanup(state->curl);
543 state->curl = NULL;
544 out_noclean:
545 g_free(s->url);
546 qemu_opts_del(opts);
547 return -EINVAL;
548 }
549
550 static void curl_aio_cancel(BlockDriverAIOCB *blockacb)
551 {
552 // Do we have to implement canceling? Seems to work without...
553 }
554
555 static const AIOCBInfo curl_aiocb_info = {
556 .aiocb_size = sizeof(CURLAIOCB),
557 .cancel = curl_aio_cancel,
558 };
559
560
561 static void curl_readv_bh_cb(void *p)
562 {
563 CURLState *state;
564
565 CURLAIOCB *acb = p;
566 BDRVCURLState *s = acb->common.bs->opaque;
567
568 qemu_bh_delete(acb->bh);
569 acb->bh = NULL;
570
571 size_t start = acb->sector_num * SECTOR_SIZE;
572 size_t end;
573
574 // In case we have the requested data already (e.g. read-ahead),
575 // we can just call the callback and be done.
576 switch (curl_find_buf(s, start, acb->nb_sectors * SECTOR_SIZE, acb)) {
577 case FIND_RET_OK:
578 qemu_aio_release(acb);
579 // fall through
580 case FIND_RET_WAIT:
581 return;
582 default:
583 break;
584 }
585
586 // No cache found, so let's start a new request
587 state = curl_init_state(s);
588 if (!state) {
589 acb->common.cb(acb->common.opaque, -EIO);
590 qemu_aio_release(acb);
591 return;
592 }
593
594 acb->start = 0;
595 acb->end = (acb->nb_sectors * SECTOR_SIZE);
596
597 state->buf_off = 0;
598 if (state->orig_buf)
599 g_free(state->orig_buf);
600 state->buf_start = start;
601 state->buf_len = acb->end + s->readahead_size;
602 end = MIN(start + state->buf_len, s->len) - 1;
603 state->orig_buf = g_malloc(state->buf_len);
604 state->acb[0] = acb;
605
606 snprintf(state->range, 127, "%zd-%zd", start, end);
607 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
608 (acb->nb_sectors * SECTOR_SIZE), start, state->range);
609 curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
610
611 curl_multi_add_handle(s->multi, state->curl);
612 curl_multi_do(s);
613
614 }
615
616 static BlockDriverAIOCB *curl_aio_readv(BlockDriverState *bs,
617 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
618 BlockDriverCompletionFunc *cb, void *opaque)
619 {
620 CURLAIOCB *acb;
621
622 acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
623
624 acb->qiov = qiov;
625 acb->sector_num = sector_num;
626 acb->nb_sectors = nb_sectors;
627
628 acb->bh = qemu_bh_new(curl_readv_bh_cb, acb);
629 qemu_bh_schedule(acb->bh);
630 return &acb->common;
631 }
632
633 static void curl_close(BlockDriverState *bs)
634 {
635 BDRVCURLState *s = bs->opaque;
636 int i;
637
638 DPRINTF("CURL: Close\n");
639 for (i=0; i<CURL_NUM_STATES; i++) {
640 if (s->states[i].in_use)
641 curl_clean_state(&s->states[i]);
642 if (s->states[i].curl) {
643 curl_easy_cleanup(s->states[i].curl);
644 s->states[i].curl = NULL;
645 }
646 if (s->states[i].orig_buf) {
647 g_free(s->states[i].orig_buf);
648 s->states[i].orig_buf = NULL;
649 }
650 }
651 if (s->multi)
652 curl_multi_cleanup(s->multi);
653
654 timer_del(&s->timer);
655
656 g_free(s->url);
657 }
658
659 static int64_t curl_getlength(BlockDriverState *bs)
660 {
661 BDRVCURLState *s = bs->opaque;
662 return s->len;
663 }
664
665 static BlockDriver bdrv_http = {
666 .format_name = "http",
667 .protocol_name = "http",
668
669 .instance_size = sizeof(BDRVCURLState),
670 .bdrv_parse_filename = curl_parse_filename,
671 .bdrv_file_open = curl_open,
672 .bdrv_close = curl_close,
673 .bdrv_getlength = curl_getlength,
674
675 .bdrv_aio_readv = curl_aio_readv,
676 };
677
678 static BlockDriver bdrv_https = {
679 .format_name = "https",
680 .protocol_name = "https",
681
682 .instance_size = sizeof(BDRVCURLState),
683 .bdrv_parse_filename = curl_parse_filename,
684 .bdrv_file_open = curl_open,
685 .bdrv_close = curl_close,
686 .bdrv_getlength = curl_getlength,
687
688 .bdrv_aio_readv = curl_aio_readv,
689 };
690
691 static BlockDriver bdrv_ftp = {
692 .format_name = "ftp",
693 .protocol_name = "ftp",
694
695 .instance_size = sizeof(BDRVCURLState),
696 .bdrv_parse_filename = curl_parse_filename,
697 .bdrv_file_open = curl_open,
698 .bdrv_close = curl_close,
699 .bdrv_getlength = curl_getlength,
700
701 .bdrv_aio_readv = curl_aio_readv,
702 };
703
704 static BlockDriver bdrv_ftps = {
705 .format_name = "ftps",
706 .protocol_name = "ftps",
707
708 .instance_size = sizeof(BDRVCURLState),
709 .bdrv_parse_filename = curl_parse_filename,
710 .bdrv_file_open = curl_open,
711 .bdrv_close = curl_close,
712 .bdrv_getlength = curl_getlength,
713
714 .bdrv_aio_readv = curl_aio_readv,
715 };
716
717 static BlockDriver bdrv_tftp = {
718 .format_name = "tftp",
719 .protocol_name = "tftp",
720
721 .instance_size = sizeof(BDRVCURLState),
722 .bdrv_parse_filename = curl_parse_filename,
723 .bdrv_file_open = curl_open,
724 .bdrv_close = curl_close,
725 .bdrv_getlength = curl_getlength,
726
727 .bdrv_aio_readv = curl_aio_readv,
728 };
729
730 static void curl_block_init(void)
731 {
732 bdrv_register(&bdrv_http);
733 bdrv_register(&bdrv_https);
734 bdrv_register(&bdrv_ftp);
735 bdrv_register(&bdrv_ftps);
736 bdrv_register(&bdrv_tftp);
737 }
738
739 block_init(curl_block_init);