2 * QEMU Block driver for CURL images
4 * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
24 #include "qemu-common.h"
25 #include "block/block_int.h"
26 #include "qapi/qmp/qbool.h"
27 #include <curl/curl.h>
30 // #define DEBUG_VERBOSE
33 #define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0)
35 #define DPRINTF(fmt, ...) do { } while (0)
38 #if LIBCURL_VERSION_NUM >= 0x071000
39 /* The multi interface timer callback was introduced in 7.16.0 */
40 #define NEED_CURL_TIMER_CALLBACK
41 #define HAVE_SOCKET_ACTION
44 #ifndef HAVE_SOCKET_ACTION
45 /* If curl_multi_socket_action isn't available, define it statically here in
46 * terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
47 * less efficient but still safe. */
48 static CURLMcode
__curl_multi_socket_action(CURLM
*multi_handle
,
53 return curl_multi_socket(multi_handle
, sockfd
, running_handles
);
55 #define curl_multi_socket_action __curl_multi_socket_action
58 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
59 CURLPROTO_FTP | CURLPROTO_FTPS | \
62 #define CURL_NUM_STATES 8
63 #define CURL_NUM_ACB 8
64 #define SECTOR_SIZE 512
65 #define READ_AHEAD_DEFAULT (256 * 1024)
67 #define FIND_RET_NONE 0
69 #define FIND_RET_WAIT 2
71 #define CURL_BLOCK_OPT_URL "url"
72 #define CURL_BLOCK_OPT_READAHEAD "readahead"
73 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
77 typedef struct CURLAIOCB
{
78 BlockDriverAIOCB common
;
89 typedef struct CURLState
91 struct BDRVCURLState
*s
;
92 CURLAIOCB
*acb
[CURL_NUM_ACB
];
94 curl_socket_t sock_fd
;
100 char errmsg
[CURL_ERROR_SIZE
];
104 typedef struct BDRVCURLState
{
108 CURLState states
[CURL_NUM_STATES
];
110 size_t readahead_size
;
113 AioContext
*aio_context
;
116 static void curl_clean_state(CURLState
*s
);
117 static void curl_multi_do(void *arg
);
118 static void curl_multi_read(void *arg
);
120 #ifdef NEED_CURL_TIMER_CALLBACK
121 static int curl_timer_cb(CURLM
*multi
, long timeout_ms
, void *opaque
)
123 BDRVCURLState
*s
= opaque
;
125 DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms
);
126 if (timeout_ms
== -1) {
127 timer_del(&s
->timer
);
129 int64_t timeout_ns
= (int64_t)timeout_ms
* 1000 * 1000;
131 qemu_clock_get_ns(QEMU_CLOCK_REALTIME
) + timeout_ns
);
137 static int curl_sock_cb(CURL
*curl
, curl_socket_t fd
, int action
,
138 void *userp
, void *sp
)
141 CURLState
*state
= NULL
;
142 curl_easy_getinfo(curl
, CURLINFO_PRIVATE
, (char **)&state
);
146 DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action
, fd
);
149 aio_set_fd_handler(s
->aio_context
, fd
, curl_multi_read
,
153 aio_set_fd_handler(s
->aio_context
, fd
, NULL
, curl_multi_do
, state
);
155 case CURL_POLL_INOUT
:
156 aio_set_fd_handler(s
->aio_context
, fd
, curl_multi_read
,
157 curl_multi_do
, state
);
159 case CURL_POLL_REMOVE
:
160 aio_set_fd_handler(s
->aio_context
, fd
, NULL
, NULL
, NULL
);
167 static size_t curl_header_cb(void *ptr
, size_t size
, size_t nmemb
, void *opaque
)
169 BDRVCURLState
*s
= opaque
;
170 size_t realsize
= size
* nmemb
;
171 const char *accept_line
= "Accept-Ranges: bytes";
173 if (realsize
>= strlen(accept_line
)
174 && strncmp((char *)ptr
, accept_line
, strlen(accept_line
)) == 0) {
175 s
->accept_range
= true;
181 static size_t curl_read_cb(void *ptr
, size_t size
, size_t nmemb
, void *opaque
)
183 CURLState
*s
= ((CURLState
*)opaque
);
184 size_t realsize
= size
* nmemb
;
187 DPRINTF("CURL: Just reading %zd bytes\n", realsize
);
189 if (!s
|| !s
->orig_buf
)
192 if (s
->buf_off
>= s
->buf_len
) {
193 /* buffer full, read nothing */
196 realsize
= MIN(realsize
, s
->buf_len
- s
->buf_off
);
197 memcpy(s
->orig_buf
+ s
->buf_off
, ptr
, realsize
);
198 s
->buf_off
+= realsize
;
200 for(i
=0; i
<CURL_NUM_ACB
; i
++) {
201 CURLAIOCB
*acb
= s
->acb
[i
];
206 if ((s
->buf_off
>= acb
->end
)) {
207 qemu_iovec_from_buf(acb
->qiov
, 0, s
->orig_buf
+ acb
->start
,
208 acb
->end
- acb
->start
);
209 acb
->common
.cb(acb
->common
.opaque
, 0);
210 qemu_aio_release(acb
);
218 static int curl_find_buf(BDRVCURLState
*s
, size_t start
, size_t len
,
222 size_t end
= start
+ len
;
224 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
225 CURLState
*state
= &s
->states
[i
];
226 size_t buf_end
= (state
->buf_start
+ state
->buf_off
);
227 size_t buf_fend
= (state
->buf_start
+ state
->buf_len
);
229 if (!state
->orig_buf
)
234 // Does the existing buffer cover our section?
235 if ((start
>= state
->buf_start
) &&
236 (start
<= buf_end
) &&
237 (end
>= state
->buf_start
) &&
240 char *buf
= state
->orig_buf
+ (start
- state
->buf_start
);
242 qemu_iovec_from_buf(acb
->qiov
, 0, buf
, len
);
243 acb
->common
.cb(acb
->common
.opaque
, 0);
248 // Wait for unfinished chunks
250 (start
>= state
->buf_start
) &&
251 (start
<= buf_fend
) &&
252 (end
>= state
->buf_start
) &&
257 acb
->start
= start
- state
->buf_start
;
258 acb
->end
= acb
->start
+ len
;
260 for (j
=0; j
<CURL_NUM_ACB
; j
++) {
261 if (!state
->acb
[j
]) {
263 return FIND_RET_WAIT
;
269 return FIND_RET_NONE
;
272 static void curl_multi_check_completion(BDRVCURLState
*s
)
276 /* Try to find done transfers, so we can free the easy
280 msg
= curl_multi_info_read(s
->multi
, &msgs_in_queue
);
282 /* Quit when there are no more completions */
286 if (msg
->msg
== CURLMSG_DONE
) {
287 CURLState
*state
= NULL
;
288 curl_easy_getinfo(msg
->easy_handle
, CURLINFO_PRIVATE
,
291 /* ACBs for successful messages get completed in curl_read_cb */
292 if (msg
->data
.result
!= CURLE_OK
) {
294 for (i
= 0; i
< CURL_NUM_ACB
; i
++) {
295 CURLAIOCB
*acb
= state
->acb
[i
];
301 acb
->common
.cb(acb
->common
.opaque
, -EIO
);
302 qemu_aio_release(acb
);
303 state
->acb
[i
] = NULL
;
307 curl_clean_state(state
);
313 static void curl_multi_do(void *arg
)
315 CURLState
*s
= (CURLState
*)arg
;
324 r
= curl_multi_socket_action(s
->s
->multi
, s
->sock_fd
, 0, &running
);
325 } while(r
== CURLM_CALL_MULTI_PERFORM
);
329 static void curl_multi_read(void *arg
)
331 CURLState
*s
= (CURLState
*)arg
;
334 curl_multi_check_completion(s
->s
);
337 static void curl_multi_timeout_do(void *arg
)
339 #ifdef NEED_CURL_TIMER_CALLBACK
340 BDRVCURLState
*s
= (BDRVCURLState
*)arg
;
347 curl_multi_socket_action(s
->multi
, CURL_SOCKET_TIMEOUT
, 0, &running
);
349 curl_multi_check_completion(s
);
355 static CURLState
*curl_init_state(BDRVCURLState
*s
)
357 CURLState
*state
= NULL
;
361 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
362 for (j
=0; j
<CURL_NUM_ACB
; j
++)
363 if (s
->states
[i
].acb
[j
])
365 if (s
->states
[i
].in_use
)
368 state
= &s
->states
[i
];
373 aio_poll(state
->s
->aio_context
, true);
378 state
->curl
= curl_easy_init();
382 curl_easy_setopt(state
->curl
, CURLOPT_URL
, s
->url
);
383 curl_easy_setopt(state
->curl
, CURLOPT_SSL_VERIFYPEER
,
384 (long) s
->sslverify
);
385 curl_easy_setopt(state
->curl
, CURLOPT_TIMEOUT
, 5);
386 curl_easy_setopt(state
->curl
, CURLOPT_WRITEFUNCTION
,
387 (void *)curl_read_cb
);
388 curl_easy_setopt(state
->curl
, CURLOPT_WRITEDATA
, (void *)state
);
389 curl_easy_setopt(state
->curl
, CURLOPT_PRIVATE
, (void *)state
);
390 curl_easy_setopt(state
->curl
, CURLOPT_AUTOREFERER
, 1);
391 curl_easy_setopt(state
->curl
, CURLOPT_FOLLOWLOCATION
, 1);
392 curl_easy_setopt(state
->curl
, CURLOPT_NOSIGNAL
, 1);
393 curl_easy_setopt(state
->curl
, CURLOPT_ERRORBUFFER
, state
->errmsg
);
394 curl_easy_setopt(state
->curl
, CURLOPT_FAILONERROR
, 1);
396 /* Restrict supported protocols to avoid security issues in the more
397 * obscure protocols. For example, do not allow POP3/SMTP/IMAP see
400 * Restricting protocols is only supported from 7.19.4 upwards.
402 #if LIBCURL_VERSION_NUM >= 0x071304
403 curl_easy_setopt(state
->curl
, CURLOPT_PROTOCOLS
, PROTOCOLS
);
404 curl_easy_setopt(state
->curl
, CURLOPT_REDIR_PROTOCOLS
, PROTOCOLS
);
408 curl_easy_setopt(state
->curl
, CURLOPT_VERBOSE
, 1);
417 static void curl_clean_state(CURLState
*s
)
420 curl_multi_remove_handle(s
->s
->multi
, s
->curl
);
424 static void curl_parse_filename(const char *filename
, QDict
*options
,
427 qdict_put(options
, CURL_BLOCK_OPT_URL
, qstring_from_str(filename
));
430 static void curl_detach_aio_context(BlockDriverState
*bs
)
432 BDRVCURLState
*s
= bs
->opaque
;
435 for (i
= 0; i
< CURL_NUM_STATES
; i
++) {
436 if (s
->states
[i
].in_use
) {
437 curl_clean_state(&s
->states
[i
]);
439 if (s
->states
[i
].curl
) {
440 curl_easy_cleanup(s
->states
[i
].curl
);
441 s
->states
[i
].curl
= NULL
;
443 g_free(s
->states
[i
].orig_buf
);
444 s
->states
[i
].orig_buf
= NULL
;
447 curl_multi_cleanup(s
->multi
);
451 timer_del(&s
->timer
);
454 static void curl_attach_aio_context(BlockDriverState
*bs
,
455 AioContext
*new_context
)
457 BDRVCURLState
*s
= bs
->opaque
;
459 aio_timer_init(new_context
, &s
->timer
,
460 QEMU_CLOCK_REALTIME
, SCALE_NS
,
461 curl_multi_timeout_do
, s
);
464 s
->multi
= curl_multi_init();
465 s
->aio_context
= new_context
;
466 curl_multi_setopt(s
->multi
, CURLMOPT_SOCKETFUNCTION
, curl_sock_cb
);
467 #ifdef NEED_CURL_TIMER_CALLBACK
468 curl_multi_setopt(s
->multi
, CURLMOPT_TIMERDATA
, s
);
469 curl_multi_setopt(s
->multi
, CURLMOPT_TIMERFUNCTION
, curl_timer_cb
);
473 static QemuOptsList runtime_opts
= {
475 .head
= QTAILQ_HEAD_INITIALIZER(runtime_opts
.head
),
478 .name
= CURL_BLOCK_OPT_URL
,
479 .type
= QEMU_OPT_STRING
,
480 .help
= "URL to open",
483 .name
= CURL_BLOCK_OPT_READAHEAD
,
484 .type
= QEMU_OPT_SIZE
,
485 .help
= "Readahead size",
488 .name
= CURL_BLOCK_OPT_SSLVERIFY
,
489 .type
= QEMU_OPT_BOOL
,
490 .help
= "Verify SSL certificate"
492 { /* end of list */ }
496 static int curl_open(BlockDriverState
*bs
, QDict
*options
, int flags
,
499 BDRVCURLState
*s
= bs
->opaque
;
500 CURLState
*state
= NULL
;
502 Error
*local_err
= NULL
;
506 static int inited
= 0;
508 if (flags
& BDRV_O_RDWR
) {
509 error_setg(errp
, "curl block device does not support writes");
513 opts
= qemu_opts_create(&runtime_opts
, NULL
, 0, &error_abort
);
514 qemu_opts_absorb_qdict(opts
, options
, &local_err
);
516 error_propagate(errp
, local_err
);
520 s
->readahead_size
= qemu_opt_get_size(opts
, CURL_BLOCK_OPT_READAHEAD
,
522 if ((s
->readahead_size
& 0x1ff) != 0) {
523 error_setg(errp
, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
528 s
->sslverify
= qemu_opt_get_bool(opts
, CURL_BLOCK_OPT_SSLVERIFY
, true);
530 file
= qemu_opt_get(opts
, CURL_BLOCK_OPT_URL
);
532 error_setg(errp
, "curl block driver requires an 'url' option");
537 curl_global_init(CURL_GLOBAL_ALL
);
541 DPRINTF("CURL: Opening %s\n", file
);
542 s
->aio_context
= bdrv_get_aio_context(bs
);
543 s
->url
= g_strdup(file
);
544 state
= curl_init_state(s
);
550 s
->accept_range
= false;
551 curl_easy_setopt(state
->curl
, CURLOPT_NOBODY
, 1);
552 curl_easy_setopt(state
->curl
, CURLOPT_HEADERFUNCTION
,
554 curl_easy_setopt(state
->curl
, CURLOPT_HEADERDATA
, s
);
555 if (curl_easy_perform(state
->curl
))
557 curl_easy_getinfo(state
->curl
, CURLINFO_CONTENT_LENGTH_DOWNLOAD
, &d
);
562 if ((!strncasecmp(s
->url
, "http://", strlen("http://"))
563 || !strncasecmp(s
->url
, "https://", strlen("https://")))
564 && !s
->accept_range
) {
565 pstrcpy(state
->errmsg
, CURL_ERROR_SIZE
,
566 "Server does not support 'range' (byte ranges).");
569 DPRINTF("CURL: Size = %zd\n", s
->len
);
571 curl_clean_state(state
);
572 curl_easy_cleanup(state
->curl
);
575 curl_attach_aio_context(bs
, bdrv_get_aio_context(bs
));
581 error_setg(errp
, "CURL: Error opening file: %s", state
->errmsg
);
582 curl_easy_cleanup(state
->curl
);
590 static void curl_aio_cancel(BlockDriverAIOCB
*blockacb
)
592 // Do we have to implement canceling? Seems to work without...
595 static const AIOCBInfo curl_aiocb_info
= {
596 .aiocb_size
= sizeof(CURLAIOCB
),
597 .cancel
= curl_aio_cancel
,
601 static void curl_readv_bh_cb(void *p
)
607 BDRVCURLState
*s
= acb
->common
.bs
->opaque
;
609 qemu_bh_delete(acb
->bh
);
612 size_t start
= acb
->sector_num
* SECTOR_SIZE
;
615 // In case we have the requested data already (e.g. read-ahead),
616 // we can just call the callback and be done.
617 switch (curl_find_buf(s
, start
, acb
->nb_sectors
* SECTOR_SIZE
, acb
)) {
619 qemu_aio_release(acb
);
627 // No cache found, so let's start a new request
628 state
= curl_init_state(s
);
630 acb
->common
.cb(acb
->common
.opaque
, -EIO
);
631 qemu_aio_release(acb
);
636 acb
->end
= (acb
->nb_sectors
* SECTOR_SIZE
);
639 g_free(state
->orig_buf
);
640 state
->buf_start
= start
;
641 state
->buf_len
= acb
->end
+ s
->readahead_size
;
642 end
= MIN(start
+ state
->buf_len
, s
->len
) - 1;
643 state
->orig_buf
= g_try_malloc(state
->buf_len
);
644 if (state
->buf_len
&& state
->orig_buf
== NULL
) {
645 curl_clean_state(state
);
646 acb
->common
.cb(acb
->common
.opaque
, -ENOMEM
);
647 qemu_aio_release(acb
);
652 snprintf(state
->range
, 127, "%zd-%zd", start
, end
);
653 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
654 (acb
->nb_sectors
* SECTOR_SIZE
), start
, state
->range
);
655 curl_easy_setopt(state
->curl
, CURLOPT_RANGE
, state
->range
);
657 curl_multi_add_handle(s
->multi
, state
->curl
);
659 /* Tell curl it needs to kick things off */
660 curl_multi_socket_action(s
->multi
, CURL_SOCKET_TIMEOUT
, 0, &running
);
663 static BlockDriverAIOCB
*curl_aio_readv(BlockDriverState
*bs
,
664 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
665 BlockDriverCompletionFunc
*cb
, void *opaque
)
669 acb
= qemu_aio_get(&curl_aiocb_info
, bs
, cb
, opaque
);
672 acb
->sector_num
= sector_num
;
673 acb
->nb_sectors
= nb_sectors
;
675 acb
->bh
= aio_bh_new(bdrv_get_aio_context(bs
), curl_readv_bh_cb
, acb
);
676 qemu_bh_schedule(acb
->bh
);
680 static void curl_close(BlockDriverState
*bs
)
682 BDRVCURLState
*s
= bs
->opaque
;
684 DPRINTF("CURL: Close\n");
685 curl_detach_aio_context(bs
);
690 static int64_t curl_getlength(BlockDriverState
*bs
)
692 BDRVCURLState
*s
= bs
->opaque
;
696 static BlockDriver bdrv_http
= {
697 .format_name
= "http",
698 .protocol_name
= "http",
700 .instance_size
= sizeof(BDRVCURLState
),
701 .bdrv_parse_filename
= curl_parse_filename
,
702 .bdrv_file_open
= curl_open
,
703 .bdrv_close
= curl_close
,
704 .bdrv_getlength
= curl_getlength
,
706 .bdrv_aio_readv
= curl_aio_readv
,
708 .bdrv_detach_aio_context
= curl_detach_aio_context
,
709 .bdrv_attach_aio_context
= curl_attach_aio_context
,
712 static BlockDriver bdrv_https
= {
713 .format_name
= "https",
714 .protocol_name
= "https",
716 .instance_size
= sizeof(BDRVCURLState
),
717 .bdrv_parse_filename
= curl_parse_filename
,
718 .bdrv_file_open
= curl_open
,
719 .bdrv_close
= curl_close
,
720 .bdrv_getlength
= curl_getlength
,
722 .bdrv_aio_readv
= curl_aio_readv
,
724 .bdrv_detach_aio_context
= curl_detach_aio_context
,
725 .bdrv_attach_aio_context
= curl_attach_aio_context
,
728 static BlockDriver bdrv_ftp
= {
729 .format_name
= "ftp",
730 .protocol_name
= "ftp",
732 .instance_size
= sizeof(BDRVCURLState
),
733 .bdrv_parse_filename
= curl_parse_filename
,
734 .bdrv_file_open
= curl_open
,
735 .bdrv_close
= curl_close
,
736 .bdrv_getlength
= curl_getlength
,
738 .bdrv_aio_readv
= curl_aio_readv
,
740 .bdrv_detach_aio_context
= curl_detach_aio_context
,
741 .bdrv_attach_aio_context
= curl_attach_aio_context
,
744 static BlockDriver bdrv_ftps
= {
745 .format_name
= "ftps",
746 .protocol_name
= "ftps",
748 .instance_size
= sizeof(BDRVCURLState
),
749 .bdrv_parse_filename
= curl_parse_filename
,
750 .bdrv_file_open
= curl_open
,
751 .bdrv_close
= curl_close
,
752 .bdrv_getlength
= curl_getlength
,
754 .bdrv_aio_readv
= curl_aio_readv
,
756 .bdrv_detach_aio_context
= curl_detach_aio_context
,
757 .bdrv_attach_aio_context
= curl_attach_aio_context
,
760 static BlockDriver bdrv_tftp
= {
761 .format_name
= "tftp",
762 .protocol_name
= "tftp",
764 .instance_size
= sizeof(BDRVCURLState
),
765 .bdrv_parse_filename
= curl_parse_filename
,
766 .bdrv_file_open
= curl_open
,
767 .bdrv_close
= curl_close
,
768 .bdrv_getlength
= curl_getlength
,
770 .bdrv_aio_readv
= curl_aio_readv
,
772 .bdrv_detach_aio_context
= curl_detach_aio_context
,
773 .bdrv_attach_aio_context
= curl_attach_aio_context
,
776 static void curl_block_init(void)
778 bdrv_register(&bdrv_http
);
779 bdrv_register(&bdrv_https
);
780 bdrv_register(&bdrv_ftp
);
781 bdrv_register(&bdrv_ftps
);
782 bdrv_register(&bdrv_tftp
);
785 block_init(curl_block_init
);