xref: /openbmc/qemu/block/curl.c (revision b969526a)
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 "qemu/error-report.h"
26 #include "block/block_int.h"
27 #include "qapi/qmp/qbool.h"
28 #include "qapi/qmp/qstring.h"
29 #include <curl/curl.h>
30 
31 // #define DEBUG_CURL
32 // #define DEBUG_VERBOSE
33 
34 #ifdef DEBUG_CURL
35 #define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0)
36 #else
37 #define DPRINTF(fmt, ...) do { } while (0)
38 #endif
39 
40 #if LIBCURL_VERSION_NUM >= 0x071000
41 /* The multi interface timer callback was introduced in 7.16.0 */
42 #define NEED_CURL_TIMER_CALLBACK
43 #define HAVE_SOCKET_ACTION
44 #endif
45 
46 #ifndef HAVE_SOCKET_ACTION
47 /* If curl_multi_socket_action isn't available, define it statically here in
48  * terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
49  * less efficient but still safe. */
50 static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
51                                             curl_socket_t sockfd,
52                                             int ev_bitmask,
53                                             int *running_handles)
54 {
55     return curl_multi_socket(multi_handle, sockfd, running_handles);
56 }
57 #define curl_multi_socket_action __curl_multi_socket_action
58 #endif
59 
60 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
61                    CURLPROTO_FTP | CURLPROTO_FTPS | \
62                    CURLPROTO_TFTP)
63 
64 #define CURL_NUM_STATES 8
65 #define CURL_NUM_ACB    8
66 #define SECTOR_SIZE     512
67 #define READ_AHEAD_DEFAULT (256 * 1024)
68 #define CURL_TIMEOUT_DEFAULT 5
69 #define CURL_TIMEOUT_MAX 10000
70 
71 #define FIND_RET_NONE   0
72 #define FIND_RET_OK     1
73 #define FIND_RET_WAIT   2
74 
75 #define CURL_BLOCK_OPT_URL       "url"
76 #define CURL_BLOCK_OPT_READAHEAD "readahead"
77 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
78 #define CURL_BLOCK_OPT_TIMEOUT "timeout"
79 #define CURL_BLOCK_OPT_COOKIE    "cookie"
80 
81 struct BDRVCURLState;
82 
83 typedef struct CURLAIOCB {
84     BlockAIOCB common;
85     QEMUBH *bh;
86     QEMUIOVector *qiov;
87 
88     int64_t sector_num;
89     int nb_sectors;
90 
91     size_t start;
92     size_t end;
93 } CURLAIOCB;
94 
95 typedef struct CURLState
96 {
97     struct BDRVCURLState *s;
98     CURLAIOCB *acb[CURL_NUM_ACB];
99     CURL *curl;
100     curl_socket_t sock_fd;
101     char *orig_buf;
102     size_t buf_start;
103     size_t buf_off;
104     size_t buf_len;
105     char range[128];
106     char errmsg[CURL_ERROR_SIZE];
107     char in_use;
108 } CURLState;
109 
110 typedef struct BDRVCURLState {
111     CURLM *multi;
112     QEMUTimer timer;
113     size_t len;
114     CURLState states[CURL_NUM_STATES];
115     char *url;
116     size_t readahead_size;
117     bool sslverify;
118     uint64_t timeout;
119     char *cookie;
120     bool accept_range;
121     AioContext *aio_context;
122 } BDRVCURLState;
123 
124 static void curl_clean_state(CURLState *s);
125 static void curl_multi_do(void *arg);
126 static void curl_multi_read(void *arg);
127 
128 #ifdef NEED_CURL_TIMER_CALLBACK
129 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
130 {
131     BDRVCURLState *s = opaque;
132 
133     DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
134     if (timeout_ms == -1) {
135         timer_del(&s->timer);
136     } else {
137         int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
138         timer_mod(&s->timer,
139                   qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
140     }
141     return 0;
142 }
143 #endif
144 
145 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
146                         void *userp, void *sp)
147 {
148     BDRVCURLState *s;
149     CURLState *state = NULL;
150     curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
151     state->sock_fd = fd;
152     s = state->s;
153 
154     DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
155     switch (action) {
156         case CURL_POLL_IN:
157             aio_set_fd_handler(s->aio_context, fd, false,
158                                curl_multi_read, NULL, state);
159             break;
160         case CURL_POLL_OUT:
161             aio_set_fd_handler(s->aio_context, fd, false,
162                                NULL, curl_multi_do, state);
163             break;
164         case CURL_POLL_INOUT:
165             aio_set_fd_handler(s->aio_context, fd, false,
166                                curl_multi_read, curl_multi_do, state);
167             break;
168         case CURL_POLL_REMOVE:
169             aio_set_fd_handler(s->aio_context, fd, false,
170                                NULL, NULL, NULL);
171             break;
172     }
173 
174     return 0;
175 }
176 
177 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
178 {
179     BDRVCURLState *s = opaque;
180     size_t realsize = size * nmemb;
181     const char *accept_line = "Accept-Ranges: bytes";
182 
183     if (realsize >= strlen(accept_line)
184         && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
185         s->accept_range = true;
186     }
187 
188     return realsize;
189 }
190 
191 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
192 {
193     CURLState *s = ((CURLState*)opaque);
194     size_t realsize = size * nmemb;
195     int i;
196 
197     DPRINTF("CURL: Just reading %zd bytes\n", realsize);
198 
199     if (!s || !s->orig_buf)
200         return 0;
201 
202     if (s->buf_off >= s->buf_len) {
203         /* buffer full, read nothing */
204         return 0;
205     }
206     realsize = MIN(realsize, s->buf_len - s->buf_off);
207     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
208     s->buf_off += realsize;
209 
210     for(i=0; i<CURL_NUM_ACB; i++) {
211         CURLAIOCB *acb = s->acb[i];
212 
213         if (!acb)
214             continue;
215 
216         if ((s->buf_off >= acb->end)) {
217             qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
218                                 acb->end - acb->start);
219             acb->common.cb(acb->common.opaque, 0);
220             qemu_aio_unref(acb);
221             s->acb[i] = NULL;
222         }
223     }
224 
225     return realsize;
226 }
227 
228 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
229                          CURLAIOCB *acb)
230 {
231     int i;
232     size_t end = start + len;
233 
234     for (i=0; i<CURL_NUM_STATES; i++) {
235         CURLState *state = &s->states[i];
236         size_t buf_end = (state->buf_start + state->buf_off);
237         size_t buf_fend = (state->buf_start + state->buf_len);
238 
239         if (!state->orig_buf)
240             continue;
241         if (!state->buf_off)
242             continue;
243 
244         // Does the existing buffer cover our section?
245         if ((start >= state->buf_start) &&
246             (start <= buf_end) &&
247             (end >= state->buf_start) &&
248             (end <= buf_end))
249         {
250             char *buf = state->orig_buf + (start - state->buf_start);
251 
252             qemu_iovec_from_buf(acb->qiov, 0, buf, len);
253             acb->common.cb(acb->common.opaque, 0);
254 
255             return FIND_RET_OK;
256         }
257 
258         // Wait for unfinished chunks
259         if (state->in_use &&
260             (start >= state->buf_start) &&
261             (start <= buf_fend) &&
262             (end >= state->buf_start) &&
263             (end <= buf_fend))
264         {
265             int j;
266 
267             acb->start = start - state->buf_start;
268             acb->end = acb->start + len;
269 
270             for (j=0; j<CURL_NUM_ACB; j++) {
271                 if (!state->acb[j]) {
272                     state->acb[j] = acb;
273                     return FIND_RET_WAIT;
274                 }
275             }
276         }
277     }
278 
279     return FIND_RET_NONE;
280 }
281 
282 static void curl_multi_check_completion(BDRVCURLState *s)
283 {
284     int msgs_in_queue;
285 
286     /* Try to find done transfers, so we can free the easy
287      * handle again. */
288     for (;;) {
289         CURLMsg *msg;
290         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
291 
292         /* Quit when there are no more completions */
293         if (!msg)
294             break;
295 
296         if (msg->msg == CURLMSG_DONE) {
297             CURLState *state = NULL;
298             curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
299                               (char **)&state);
300 
301             /* ACBs for successful messages get completed in curl_read_cb */
302             if (msg->data.result != CURLE_OK) {
303                 int i;
304                 static int errcount = 100;
305 
306                 /* Don't lose the original error message from curl, since
307                  * it contains extra data.
308                  */
309                 if (errcount > 0) {
310                     error_report("curl: %s", state->errmsg);
311                     if (--errcount == 0) {
312                         error_report("curl: further errors suppressed");
313                     }
314                 }
315 
316                 for (i = 0; i < CURL_NUM_ACB; i++) {
317                     CURLAIOCB *acb = state->acb[i];
318 
319                     if (acb == NULL) {
320                         continue;
321                     }
322 
323                     acb->common.cb(acb->common.opaque, -EPROTO);
324                     qemu_aio_unref(acb);
325                     state->acb[i] = NULL;
326                 }
327             }
328 
329             curl_clean_state(state);
330             break;
331         }
332     }
333 }
334 
335 static void curl_multi_do(void *arg)
336 {
337     CURLState *s = (CURLState *)arg;
338     int running;
339     int r;
340 
341     if (!s->s->multi) {
342         return;
343     }
344 
345     do {
346         r = curl_multi_socket_action(s->s->multi, s->sock_fd, 0, &running);
347     } while(r == CURLM_CALL_MULTI_PERFORM);
348 
349 }
350 
351 static void curl_multi_read(void *arg)
352 {
353     CURLState *s = (CURLState *)arg;
354 
355     curl_multi_do(arg);
356     curl_multi_check_completion(s->s);
357 }
358 
359 static void curl_multi_timeout_do(void *arg)
360 {
361 #ifdef NEED_CURL_TIMER_CALLBACK
362     BDRVCURLState *s = (BDRVCURLState *)arg;
363     int running;
364 
365     if (!s->multi) {
366         return;
367     }
368 
369     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
370 
371     curl_multi_check_completion(s);
372 #else
373     abort();
374 #endif
375 }
376 
377 static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
378 {
379     CURLState *state = NULL;
380     int i, j;
381 
382     do {
383         for (i=0; i<CURL_NUM_STATES; i++) {
384             for (j=0; j<CURL_NUM_ACB; j++)
385                 if (s->states[i].acb[j])
386                     continue;
387             if (s->states[i].in_use)
388                 continue;
389 
390             state = &s->states[i];
391             state->in_use = 1;
392             break;
393         }
394         if (!state) {
395             aio_poll(bdrv_get_aio_context(bs), true);
396         }
397     } while(!state);
398 
399     if (!state->curl) {
400         state->curl = curl_easy_init();
401         if (!state->curl) {
402             return NULL;
403         }
404         curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
405         curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
406                          (long) s->sslverify);
407         if (s->cookie) {
408             curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
409         }
410         curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
411         curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
412                          (void *)curl_read_cb);
413         curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
414         curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
415         curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
416         curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
417         curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
418         curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
419         curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
420 
421         /* Restrict supported protocols to avoid security issues in the more
422          * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
423          * CVE-2013-0249.
424          *
425          * Restricting protocols is only supported from 7.19.4 upwards.
426          */
427 #if LIBCURL_VERSION_NUM >= 0x071304
428         curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
429         curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
430 #endif
431 
432 #ifdef DEBUG_VERBOSE
433         curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
434 #endif
435     }
436 
437     state->s = s;
438 
439     return state;
440 }
441 
442 static void curl_clean_state(CURLState *s)
443 {
444     if (s->s->multi)
445         curl_multi_remove_handle(s->s->multi, s->curl);
446     s->in_use = 0;
447 }
448 
449 static void curl_parse_filename(const char *filename, QDict *options,
450                                 Error **errp)
451 {
452     qdict_put(options, CURL_BLOCK_OPT_URL, qstring_from_str(filename));
453 }
454 
455 static void curl_detach_aio_context(BlockDriverState *bs)
456 {
457     BDRVCURLState *s = bs->opaque;
458     int i;
459 
460     for (i = 0; i < CURL_NUM_STATES; i++) {
461         if (s->states[i].in_use) {
462             curl_clean_state(&s->states[i]);
463         }
464         if (s->states[i].curl) {
465             curl_easy_cleanup(s->states[i].curl);
466             s->states[i].curl = NULL;
467         }
468         g_free(s->states[i].orig_buf);
469         s->states[i].orig_buf = NULL;
470     }
471     if (s->multi) {
472         curl_multi_cleanup(s->multi);
473         s->multi = NULL;
474     }
475 
476     timer_del(&s->timer);
477 }
478 
479 static void curl_attach_aio_context(BlockDriverState *bs,
480                                     AioContext *new_context)
481 {
482     BDRVCURLState *s = bs->opaque;
483 
484     aio_timer_init(new_context, &s->timer,
485                    QEMU_CLOCK_REALTIME, SCALE_NS,
486                    curl_multi_timeout_do, s);
487 
488     assert(!s->multi);
489     s->multi = curl_multi_init();
490     s->aio_context = new_context;
491     curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
492 #ifdef NEED_CURL_TIMER_CALLBACK
493     curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
494     curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
495 #endif
496 }
497 
498 static QemuOptsList runtime_opts = {
499     .name = "curl",
500     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
501     .desc = {
502         {
503             .name = CURL_BLOCK_OPT_URL,
504             .type = QEMU_OPT_STRING,
505             .help = "URL to open",
506         },
507         {
508             .name = CURL_BLOCK_OPT_READAHEAD,
509             .type = QEMU_OPT_SIZE,
510             .help = "Readahead size",
511         },
512         {
513             .name = CURL_BLOCK_OPT_SSLVERIFY,
514             .type = QEMU_OPT_BOOL,
515             .help = "Verify SSL certificate"
516         },
517         {
518             .name = CURL_BLOCK_OPT_TIMEOUT,
519             .type = QEMU_OPT_NUMBER,
520             .help = "Curl timeout"
521         },
522         {
523             .name = CURL_BLOCK_OPT_COOKIE,
524             .type = QEMU_OPT_STRING,
525             .help = "Pass the cookie or list of cookies with each request"
526         },
527         { /* end of list */ }
528     },
529 };
530 
531 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
532                      Error **errp)
533 {
534     BDRVCURLState *s = bs->opaque;
535     CURLState *state = NULL;
536     QemuOpts *opts;
537     Error *local_err = NULL;
538     const char *file;
539     const char *cookie;
540     double d;
541 
542     static int inited = 0;
543 
544     if (flags & BDRV_O_RDWR) {
545         error_setg(errp, "curl block device does not support writes");
546         return -EROFS;
547     }
548 
549     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
550     qemu_opts_absorb_qdict(opts, options, &local_err);
551     if (local_err) {
552         error_propagate(errp, local_err);
553         goto out_noclean;
554     }
555 
556     s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
557                                           READ_AHEAD_DEFAULT);
558     if ((s->readahead_size & 0x1ff) != 0) {
559         error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
560                    s->readahead_size);
561         goto out_noclean;
562     }
563 
564     s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
565                                      CURL_TIMEOUT_DEFAULT);
566     if (s->timeout > CURL_TIMEOUT_MAX) {
567         error_setg(errp, "timeout parameter is too large or negative");
568         goto out_noclean;
569     }
570 
571     s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
572 
573     cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
574     s->cookie = g_strdup(cookie);
575 
576     file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
577     if (file == NULL) {
578         error_setg(errp, "curl block driver requires an 'url' option");
579         goto out_noclean;
580     }
581 
582     if (!inited) {
583         curl_global_init(CURL_GLOBAL_ALL);
584         inited = 1;
585     }
586 
587     DPRINTF("CURL: Opening %s\n", file);
588     s->aio_context = bdrv_get_aio_context(bs);
589     s->url = g_strdup(file);
590     state = curl_init_state(bs, s);
591     if (!state)
592         goto out_noclean;
593 
594     // Get file size
595 
596     s->accept_range = false;
597     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
598     curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
599                      curl_header_cb);
600     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
601     if (curl_easy_perform(state->curl))
602         goto out;
603     curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
604     if (d)
605         s->len = (size_t)d;
606     else if(!s->len)
607         goto out;
608     if ((!strncasecmp(s->url, "http://", strlen("http://"))
609         || !strncasecmp(s->url, "https://", strlen("https://")))
610         && !s->accept_range) {
611         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
612                 "Server does not support 'range' (byte ranges).");
613         goto out;
614     }
615     DPRINTF("CURL: Size = %zd\n", s->len);
616 
617     curl_clean_state(state);
618     curl_easy_cleanup(state->curl);
619     state->curl = NULL;
620 
621     curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
622 
623     qemu_opts_del(opts);
624     return 0;
625 
626 out:
627     error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
628     curl_easy_cleanup(state->curl);
629     state->curl = NULL;
630 out_noclean:
631     g_free(s->cookie);
632     g_free(s->url);
633     qemu_opts_del(opts);
634     return -EINVAL;
635 }
636 
637 static const AIOCBInfo curl_aiocb_info = {
638     .aiocb_size         = sizeof(CURLAIOCB),
639 };
640 
641 
642 static void curl_readv_bh_cb(void *p)
643 {
644     CURLState *state;
645     int running;
646 
647     CURLAIOCB *acb = p;
648     BDRVCURLState *s = acb->common.bs->opaque;
649 
650     qemu_bh_delete(acb->bh);
651     acb->bh = NULL;
652 
653     size_t start = acb->sector_num * SECTOR_SIZE;
654     size_t end;
655 
656     // In case we have the requested data already (e.g. read-ahead),
657     // we can just call the callback and be done.
658     switch (curl_find_buf(s, start, acb->nb_sectors * SECTOR_SIZE, acb)) {
659         case FIND_RET_OK:
660             qemu_aio_unref(acb);
661             // fall through
662         case FIND_RET_WAIT:
663             return;
664         default:
665             break;
666     }
667 
668     // No cache found, so let's start a new request
669     state = curl_init_state(acb->common.bs, s);
670     if (!state) {
671         acb->common.cb(acb->common.opaque, -EIO);
672         qemu_aio_unref(acb);
673         return;
674     }
675 
676     acb->start = 0;
677     acb->end = (acb->nb_sectors * SECTOR_SIZE);
678 
679     state->buf_off = 0;
680     g_free(state->orig_buf);
681     state->buf_start = start;
682     state->buf_len = acb->end + s->readahead_size;
683     end = MIN(start + state->buf_len, s->len) - 1;
684     state->orig_buf = g_try_malloc(state->buf_len);
685     if (state->buf_len && state->orig_buf == NULL) {
686         curl_clean_state(state);
687         acb->common.cb(acb->common.opaque, -ENOMEM);
688         qemu_aio_unref(acb);
689         return;
690     }
691     state->acb[0] = acb;
692 
693     snprintf(state->range, 127, "%zd-%zd", start, end);
694     DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
695             (acb->nb_sectors * SECTOR_SIZE), start, state->range);
696     curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
697 
698     curl_multi_add_handle(s->multi, state->curl);
699 
700     /* Tell curl it needs to kick things off */
701     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
702 }
703 
704 static BlockAIOCB *curl_aio_readv(BlockDriverState *bs,
705         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
706         BlockCompletionFunc *cb, void *opaque)
707 {
708     CURLAIOCB *acb;
709 
710     acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
711 
712     acb->qiov = qiov;
713     acb->sector_num = sector_num;
714     acb->nb_sectors = nb_sectors;
715 
716     acb->bh = aio_bh_new(bdrv_get_aio_context(bs), curl_readv_bh_cb, acb);
717     qemu_bh_schedule(acb->bh);
718     return &acb->common;
719 }
720 
721 static void curl_close(BlockDriverState *bs)
722 {
723     BDRVCURLState *s = bs->opaque;
724 
725     DPRINTF("CURL: Close\n");
726     curl_detach_aio_context(bs);
727 
728     g_free(s->cookie);
729     g_free(s->url);
730 }
731 
732 static int64_t curl_getlength(BlockDriverState *bs)
733 {
734     BDRVCURLState *s = bs->opaque;
735     return s->len;
736 }
737 
738 static BlockDriver bdrv_http = {
739     .format_name                = "http",
740     .protocol_name              = "http",
741 
742     .instance_size              = sizeof(BDRVCURLState),
743     .bdrv_parse_filename        = curl_parse_filename,
744     .bdrv_file_open             = curl_open,
745     .bdrv_close                 = curl_close,
746     .bdrv_getlength             = curl_getlength,
747 
748     .bdrv_aio_readv             = curl_aio_readv,
749 
750     .bdrv_detach_aio_context    = curl_detach_aio_context,
751     .bdrv_attach_aio_context    = curl_attach_aio_context,
752 };
753 
754 static BlockDriver bdrv_https = {
755     .format_name                = "https",
756     .protocol_name              = "https",
757 
758     .instance_size              = sizeof(BDRVCURLState),
759     .bdrv_parse_filename        = curl_parse_filename,
760     .bdrv_file_open             = curl_open,
761     .bdrv_close                 = curl_close,
762     .bdrv_getlength             = curl_getlength,
763 
764     .bdrv_aio_readv             = curl_aio_readv,
765 
766     .bdrv_detach_aio_context    = curl_detach_aio_context,
767     .bdrv_attach_aio_context    = curl_attach_aio_context,
768 };
769 
770 static BlockDriver bdrv_ftp = {
771     .format_name                = "ftp",
772     .protocol_name              = "ftp",
773 
774     .instance_size              = sizeof(BDRVCURLState),
775     .bdrv_parse_filename        = curl_parse_filename,
776     .bdrv_file_open             = curl_open,
777     .bdrv_close                 = curl_close,
778     .bdrv_getlength             = curl_getlength,
779 
780     .bdrv_aio_readv             = curl_aio_readv,
781 
782     .bdrv_detach_aio_context    = curl_detach_aio_context,
783     .bdrv_attach_aio_context    = curl_attach_aio_context,
784 };
785 
786 static BlockDriver bdrv_ftps = {
787     .format_name                = "ftps",
788     .protocol_name              = "ftps",
789 
790     .instance_size              = sizeof(BDRVCURLState),
791     .bdrv_parse_filename        = curl_parse_filename,
792     .bdrv_file_open             = curl_open,
793     .bdrv_close                 = curl_close,
794     .bdrv_getlength             = curl_getlength,
795 
796     .bdrv_aio_readv             = curl_aio_readv,
797 
798     .bdrv_detach_aio_context    = curl_detach_aio_context,
799     .bdrv_attach_aio_context    = curl_attach_aio_context,
800 };
801 
802 static BlockDriver bdrv_tftp = {
803     .format_name                = "tftp",
804     .protocol_name              = "tftp",
805 
806     .instance_size              = sizeof(BDRVCURLState),
807     .bdrv_parse_filename        = curl_parse_filename,
808     .bdrv_file_open             = curl_open,
809     .bdrv_close                 = curl_close,
810     .bdrv_getlength             = curl_getlength,
811 
812     .bdrv_aio_readv             = curl_aio_readv,
813 
814     .bdrv_detach_aio_context    = curl_detach_aio_context,
815     .bdrv_attach_aio_context    = curl_attach_aio_context,
816 };
817 
818 static void curl_block_init(void)
819 {
820     bdrv_register(&bdrv_http);
821     bdrv_register(&bdrv_https);
822     bdrv_register(&bdrv_ftp);
823     bdrv_register(&bdrv_ftps);
824     bdrv_register(&bdrv_tftp);
825 }
826 
827 block_init(curl_block_init);
828