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
;
115 static void curl_clean_state(CURLState
*s
);
116 static void curl_multi_do(void *arg
);
117 static void curl_multi_read(void *arg
);
119 #ifdef NEED_CURL_TIMER_CALLBACK
120 static int curl_timer_cb(CURLM
*multi
, long timeout_ms
, void *opaque
)
122 BDRVCURLState
*s
= opaque
;
124 DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms
);
125 if (timeout_ms
== -1) {
126 timer_del(&s
->timer
);
128 int64_t timeout_ns
= (int64_t)timeout_ms
* 1000 * 1000;
130 qemu_clock_get_ns(QEMU_CLOCK_REALTIME
) + timeout_ns
);
136 static int curl_sock_cb(CURL
*curl
, curl_socket_t fd
, int action
,
139 CURLState
*state
= NULL
;
140 curl_easy_getinfo(curl
, CURLINFO_PRIVATE
, (char **)&state
);
143 DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action
, fd
);
146 qemu_aio_set_fd_handler(fd
, curl_multi_read
, NULL
, state
);
149 qemu_aio_set_fd_handler(fd
, NULL
, curl_multi_do
, state
);
151 case CURL_POLL_INOUT
:
152 qemu_aio_set_fd_handler(fd
, curl_multi_read
, curl_multi_do
, state
);
154 case CURL_POLL_REMOVE
:
155 qemu_aio_set_fd_handler(fd
, NULL
, NULL
, NULL
);
162 static size_t curl_header_cb(void *ptr
, size_t size
, size_t nmemb
, void *opaque
)
164 BDRVCURLState
*s
= opaque
;
165 size_t realsize
= size
* nmemb
;
166 const char *accept_line
= "Accept-Ranges: bytes";
168 if (realsize
>= strlen(accept_line
)
169 && strncmp((char *)ptr
, accept_line
, strlen(accept_line
)) == 0) {
170 s
->accept_range
= true;
176 static size_t curl_read_cb(void *ptr
, size_t size
, size_t nmemb
, void *opaque
)
178 CURLState
*s
= ((CURLState
*)opaque
);
179 size_t realsize
= size
* nmemb
;
182 DPRINTF("CURL: Just reading %zd bytes\n", realsize
);
184 if (!s
|| !s
->orig_buf
)
187 if (s
->buf_off
>= s
->buf_len
) {
188 /* buffer full, read nothing */
191 realsize
= MIN(realsize
, s
->buf_len
- s
->buf_off
);
192 memcpy(s
->orig_buf
+ s
->buf_off
, ptr
, realsize
);
193 s
->buf_off
+= realsize
;
195 for(i
=0; i
<CURL_NUM_ACB
; i
++) {
196 CURLAIOCB
*acb
= s
->acb
[i
];
201 if ((s
->buf_off
>= acb
->end
)) {
202 qemu_iovec_from_buf(acb
->qiov
, 0, s
->orig_buf
+ acb
->start
,
203 acb
->end
- acb
->start
);
204 acb
->common
.cb(acb
->common
.opaque
, 0);
205 qemu_aio_release(acb
);
213 static int curl_find_buf(BDRVCURLState
*s
, size_t start
, size_t len
,
217 size_t end
= start
+ len
;
219 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
220 CURLState
*state
= &s
->states
[i
];
221 size_t buf_end
= (state
->buf_start
+ state
->buf_off
);
222 size_t buf_fend
= (state
->buf_start
+ state
->buf_len
);
224 if (!state
->orig_buf
)
229 // Does the existing buffer cover our section?
230 if ((start
>= state
->buf_start
) &&
231 (start
<= buf_end
) &&
232 (end
>= state
->buf_start
) &&
235 char *buf
= state
->orig_buf
+ (start
- state
->buf_start
);
237 qemu_iovec_from_buf(acb
->qiov
, 0, buf
, len
);
238 acb
->common
.cb(acb
->common
.opaque
, 0);
243 // Wait for unfinished chunks
245 (start
>= state
->buf_start
) &&
246 (start
<= buf_fend
) &&
247 (end
>= state
->buf_start
) &&
252 acb
->start
= start
- state
->buf_start
;
253 acb
->end
= acb
->start
+ len
;
255 for (j
=0; j
<CURL_NUM_ACB
; j
++) {
256 if (!state
->acb
[j
]) {
258 return FIND_RET_WAIT
;
264 return FIND_RET_NONE
;
267 static void curl_multi_check_completion(BDRVCURLState
*s
)
271 /* Try to find done transfers, so we can free the easy
275 msg
= curl_multi_info_read(s
->multi
, &msgs_in_queue
);
277 /* Quit when there are no more completions */
281 if (msg
->msg
== CURLMSG_DONE
) {
282 CURLState
*state
= NULL
;
283 curl_easy_getinfo(msg
->easy_handle
, CURLINFO_PRIVATE
,
286 /* ACBs for successful messages get completed in curl_read_cb */
287 if (msg
->data
.result
!= CURLE_OK
) {
289 for (i
= 0; i
< CURL_NUM_ACB
; i
++) {
290 CURLAIOCB
*acb
= state
->acb
[i
];
296 acb
->common
.cb(acb
->common
.opaque
, -EIO
);
297 qemu_aio_release(acb
);
298 state
->acb
[i
] = NULL
;
302 curl_clean_state(state
);
308 static void curl_multi_do(void *arg
)
310 CURLState
*s
= (CURLState
*)arg
;
319 r
= curl_multi_socket_action(s
->s
->multi
, s
->sock_fd
, 0, &running
);
320 } while(r
== CURLM_CALL_MULTI_PERFORM
);
324 static void curl_multi_read(void *arg
)
326 CURLState
*s
= (CURLState
*)arg
;
329 curl_multi_check_completion(s
->s
);
332 static void curl_multi_timeout_do(void *arg
)
334 #ifdef NEED_CURL_TIMER_CALLBACK
335 BDRVCURLState
*s
= (BDRVCURLState
*)arg
;
342 curl_multi_socket_action(s
->multi
, CURL_SOCKET_TIMEOUT
, 0, &running
);
344 curl_multi_check_completion(s
);
350 static CURLState
*curl_init_state(BDRVCURLState
*s
)
352 CURLState
*state
= NULL
;
356 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
357 for (j
=0; j
<CURL_NUM_ACB
; j
++)
358 if (s
->states
[i
].acb
[j
])
360 if (s
->states
[i
].in_use
)
363 state
= &s
->states
[i
];
373 state
->curl
= curl_easy_init();
377 curl_easy_setopt(state
->curl
, CURLOPT_URL
, s
->url
);
378 curl_easy_setopt(state
->curl
, CURLOPT_SSL_VERIFYPEER
,
379 (long) s
->sslverify
);
380 curl_easy_setopt(state
->curl
, CURLOPT_TIMEOUT
, 5);
381 curl_easy_setopt(state
->curl
, CURLOPT_WRITEFUNCTION
,
382 (void *)curl_read_cb
);
383 curl_easy_setopt(state
->curl
, CURLOPT_WRITEDATA
, (void *)state
);
384 curl_easy_setopt(state
->curl
, CURLOPT_PRIVATE
, (void *)state
);
385 curl_easy_setopt(state
->curl
, CURLOPT_AUTOREFERER
, 1);
386 curl_easy_setopt(state
->curl
, CURLOPT_FOLLOWLOCATION
, 1);
387 curl_easy_setopt(state
->curl
, CURLOPT_NOSIGNAL
, 1);
388 curl_easy_setopt(state
->curl
, CURLOPT_ERRORBUFFER
, state
->errmsg
);
389 curl_easy_setopt(state
->curl
, CURLOPT_FAILONERROR
, 1);
391 /* Restrict supported protocols to avoid security issues in the more
392 * obscure protocols. For example, do not allow POP3/SMTP/IMAP see
395 * Restricting protocols is only supported from 7.19.4 upwards.
397 #if LIBCURL_VERSION_NUM >= 0x071304
398 curl_easy_setopt(state
->curl
, CURLOPT_PROTOCOLS
, PROTOCOLS
);
399 curl_easy_setopt(state
->curl
, CURLOPT_REDIR_PROTOCOLS
, PROTOCOLS
);
403 curl_easy_setopt(state
->curl
, CURLOPT_VERBOSE
, 1);
412 static void curl_clean_state(CURLState
*s
)
415 curl_multi_remove_handle(s
->s
->multi
, s
->curl
);
419 static void curl_parse_filename(const char *filename
, QDict
*options
,
422 qdict_put(options
, CURL_BLOCK_OPT_URL
, qstring_from_str(filename
));
425 static QemuOptsList runtime_opts
= {
427 .head
= QTAILQ_HEAD_INITIALIZER(runtime_opts
.head
),
430 .name
= CURL_BLOCK_OPT_URL
,
431 .type
= QEMU_OPT_STRING
,
432 .help
= "URL to open",
435 .name
= CURL_BLOCK_OPT_READAHEAD
,
436 .type
= QEMU_OPT_SIZE
,
437 .help
= "Readahead size",
440 .name
= CURL_BLOCK_OPT_SSLVERIFY
,
441 .type
= QEMU_OPT_BOOL
,
442 .help
= "Verify SSL certificate"
444 { /* end of list */ }
448 static int curl_open(BlockDriverState
*bs
, QDict
*options
, int flags
,
451 BDRVCURLState
*s
= bs
->opaque
;
452 CURLState
*state
= NULL
;
454 Error
*local_err
= NULL
;
458 static int inited
= 0;
460 if (flags
& BDRV_O_RDWR
) {
461 error_setg(errp
, "curl block device does not support writes");
465 opts
= qemu_opts_create(&runtime_opts
, NULL
, 0, &error_abort
);
466 qemu_opts_absorb_qdict(opts
, options
, &local_err
);
468 error_propagate(errp
, local_err
);
472 s
->readahead_size
= qemu_opt_get_size(opts
, CURL_BLOCK_OPT_READAHEAD
,
474 if ((s
->readahead_size
& 0x1ff) != 0) {
475 error_setg(errp
, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
480 s
->sslverify
= qemu_opt_get_bool(opts
, CURL_BLOCK_OPT_SSLVERIFY
, true);
482 file
= qemu_opt_get(opts
, CURL_BLOCK_OPT_URL
);
484 error_setg(errp
, "curl block driver requires an 'url' option");
489 curl_global_init(CURL_GLOBAL_ALL
);
493 DPRINTF("CURL: Opening %s\n", file
);
494 s
->url
= g_strdup(file
);
495 state
= curl_init_state(s
);
501 s
->accept_range
= false;
502 curl_easy_setopt(state
->curl
, CURLOPT_NOBODY
, 1);
503 curl_easy_setopt(state
->curl
, CURLOPT_HEADERFUNCTION
,
505 curl_easy_setopt(state
->curl
, CURLOPT_HEADERDATA
, s
);
506 if (curl_easy_perform(state
->curl
))
508 curl_easy_getinfo(state
->curl
, CURLINFO_CONTENT_LENGTH_DOWNLOAD
, &d
);
513 if ((!strncasecmp(s
->url
, "http://", strlen("http://"))
514 || !strncasecmp(s
->url
, "https://", strlen("https://")))
515 && !s
->accept_range
) {
516 pstrcpy(state
->errmsg
, CURL_ERROR_SIZE
,
517 "Server does not support 'range' (byte ranges).");
520 DPRINTF("CURL: Size = %zd\n", s
->len
);
522 curl_clean_state(state
);
523 curl_easy_cleanup(state
->curl
);
526 aio_timer_init(bdrv_get_aio_context(bs
), &s
->timer
,
527 QEMU_CLOCK_REALTIME
, SCALE_NS
,
528 curl_multi_timeout_do
, s
);
530 // Now we know the file exists and its size, so let's
531 // initialize the multi interface!
533 s
->multi
= curl_multi_init();
534 curl_multi_setopt(s
->multi
, CURLMOPT_SOCKETFUNCTION
, curl_sock_cb
);
535 #ifdef NEED_CURL_TIMER_CALLBACK
536 curl_multi_setopt(s
->multi
, CURLMOPT_TIMERDATA
, s
);
537 curl_multi_setopt(s
->multi
, CURLMOPT_TIMERFUNCTION
, curl_timer_cb
);
544 error_setg(errp
, "CURL: Error opening file: %s", state
->errmsg
);
545 curl_easy_cleanup(state
->curl
);
553 static void curl_aio_cancel(BlockDriverAIOCB
*blockacb
)
555 // Do we have to implement canceling? Seems to work without...
558 static const AIOCBInfo curl_aiocb_info
= {
559 .aiocb_size
= sizeof(CURLAIOCB
),
560 .cancel
= curl_aio_cancel
,
564 static void curl_readv_bh_cb(void *p
)
570 BDRVCURLState
*s
= acb
->common
.bs
->opaque
;
572 qemu_bh_delete(acb
->bh
);
575 size_t start
= acb
->sector_num
* SECTOR_SIZE
;
578 // In case we have the requested data already (e.g. read-ahead),
579 // we can just call the callback and be done.
580 switch (curl_find_buf(s
, start
, acb
->nb_sectors
* SECTOR_SIZE
, acb
)) {
582 qemu_aio_release(acb
);
590 // No cache found, so let's start a new request
591 state
= curl_init_state(s
);
593 acb
->common
.cb(acb
->common
.opaque
, -EIO
);
594 qemu_aio_release(acb
);
599 acb
->end
= (acb
->nb_sectors
* SECTOR_SIZE
);
603 g_free(state
->orig_buf
);
604 state
->buf_start
= start
;
605 state
->buf_len
= acb
->end
+ s
->readahead_size
;
606 end
= MIN(start
+ state
->buf_len
, s
->len
) - 1;
607 state
->orig_buf
= g_malloc(state
->buf_len
);
610 snprintf(state
->range
, 127, "%zd-%zd", start
, end
);
611 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
612 (acb
->nb_sectors
* SECTOR_SIZE
), start
, state
->range
);
613 curl_easy_setopt(state
->curl
, CURLOPT_RANGE
, state
->range
);
615 curl_multi_add_handle(s
->multi
, state
->curl
);
617 /* Tell curl it needs to kick things off */
618 curl_multi_socket_action(s
->multi
, CURL_SOCKET_TIMEOUT
, 0, &running
);
621 static BlockDriverAIOCB
*curl_aio_readv(BlockDriverState
*bs
,
622 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
623 BlockDriverCompletionFunc
*cb
, void *opaque
)
627 acb
= qemu_aio_get(&curl_aiocb_info
, bs
, cb
, opaque
);
630 acb
->sector_num
= sector_num
;
631 acb
->nb_sectors
= nb_sectors
;
633 acb
->bh
= qemu_bh_new(curl_readv_bh_cb
, acb
);
634 qemu_bh_schedule(acb
->bh
);
638 static void curl_close(BlockDriverState
*bs
)
640 BDRVCURLState
*s
= bs
->opaque
;
643 DPRINTF("CURL: Close\n");
644 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
645 if (s
->states
[i
].in_use
)
646 curl_clean_state(&s
->states
[i
]);
647 if (s
->states
[i
].curl
) {
648 curl_easy_cleanup(s
->states
[i
].curl
);
649 s
->states
[i
].curl
= NULL
;
651 if (s
->states
[i
].orig_buf
) {
652 g_free(s
->states
[i
].orig_buf
);
653 s
->states
[i
].orig_buf
= NULL
;
657 curl_multi_cleanup(s
->multi
);
659 timer_del(&s
->timer
);
664 static int64_t curl_getlength(BlockDriverState
*bs
)
666 BDRVCURLState
*s
= bs
->opaque
;
670 static BlockDriver bdrv_http
= {
671 .format_name
= "http",
672 .protocol_name
= "http",
674 .instance_size
= sizeof(BDRVCURLState
),
675 .bdrv_parse_filename
= curl_parse_filename
,
676 .bdrv_file_open
= curl_open
,
677 .bdrv_close
= curl_close
,
678 .bdrv_getlength
= curl_getlength
,
680 .bdrv_aio_readv
= curl_aio_readv
,
683 static BlockDriver bdrv_https
= {
684 .format_name
= "https",
685 .protocol_name
= "https",
687 .instance_size
= sizeof(BDRVCURLState
),
688 .bdrv_parse_filename
= curl_parse_filename
,
689 .bdrv_file_open
= curl_open
,
690 .bdrv_close
= curl_close
,
691 .bdrv_getlength
= curl_getlength
,
693 .bdrv_aio_readv
= curl_aio_readv
,
696 static BlockDriver bdrv_ftp
= {
697 .format_name
= "ftp",
698 .protocol_name
= "ftp",
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
,
709 static BlockDriver bdrv_ftps
= {
710 .format_name
= "ftps",
711 .protocol_name
= "ftps",
713 .instance_size
= sizeof(BDRVCURLState
),
714 .bdrv_parse_filename
= curl_parse_filename
,
715 .bdrv_file_open
= curl_open
,
716 .bdrv_close
= curl_close
,
717 .bdrv_getlength
= curl_getlength
,
719 .bdrv_aio_readv
= curl_aio_readv
,
722 static BlockDriver bdrv_tftp
= {
723 .format_name
= "tftp",
724 .protocol_name
= "tftp",
726 .instance_size
= sizeof(BDRVCURLState
),
727 .bdrv_parse_filename
= curl_parse_filename
,
728 .bdrv_file_open
= curl_open
,
729 .bdrv_close
= curl_close
,
730 .bdrv_getlength
= curl_getlength
,
732 .bdrv_aio_readv
= curl_aio_readv
,
735 static void curl_block_init(void)
737 bdrv_register(&bdrv_http
);
738 bdrv_register(&bdrv_https
);
739 bdrv_register(&bdrv_ftp
);
740 bdrv_register(&bdrv_ftps
);
741 bdrv_register(&bdrv_tftp
);
744 block_init(curl_block_init
);