]> git.proxmox.com Git - qemu.git/blob - block/curl.c
target-i386: ROR r8/r16 imm instruction fix
[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 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
38 CURLPROTO_FTP | CURLPROTO_FTPS | \
39 CURLPROTO_TFTP)
40
41 #define CURL_NUM_STATES 8
42 #define CURL_NUM_ACB 8
43 #define SECTOR_SIZE 512
44 #define READ_AHEAD_SIZE (256 * 1024)
45
46 #define FIND_RET_NONE 0
47 #define FIND_RET_OK 1
48 #define FIND_RET_WAIT 2
49
50 struct BDRVCURLState;
51
52 typedef struct CURLAIOCB {
53 BlockDriverAIOCB common;
54 QEMUBH *bh;
55 QEMUIOVector *qiov;
56
57 int64_t sector_num;
58 int nb_sectors;
59
60 size_t start;
61 size_t end;
62 } CURLAIOCB;
63
64 typedef struct CURLState
65 {
66 struct BDRVCURLState *s;
67 CURLAIOCB *acb[CURL_NUM_ACB];
68 CURL *curl;
69 char *orig_buf;
70 size_t buf_start;
71 size_t buf_off;
72 size_t buf_len;
73 char range[128];
74 char errmsg[CURL_ERROR_SIZE];
75 char in_use;
76 } CURLState;
77
78 typedef struct BDRVCURLState {
79 CURLM *multi;
80 size_t len;
81 CURLState states[CURL_NUM_STATES];
82 char *url;
83 size_t readahead_size;
84 } BDRVCURLState;
85
86 static void curl_clean_state(CURLState *s);
87 static void curl_multi_do(void *arg);
88 static int curl_aio_flush(void *opaque);
89
90 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
91 void *s, void *sp)
92 {
93 DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
94 switch (action) {
95 case CURL_POLL_IN:
96 qemu_aio_set_fd_handler(fd, curl_multi_do, NULL, curl_aio_flush, s);
97 break;
98 case CURL_POLL_OUT:
99 qemu_aio_set_fd_handler(fd, NULL, curl_multi_do, curl_aio_flush, s);
100 break;
101 case CURL_POLL_INOUT:
102 qemu_aio_set_fd_handler(fd, curl_multi_do, curl_multi_do,
103 curl_aio_flush, s);
104 break;
105 case CURL_POLL_REMOVE:
106 qemu_aio_set_fd_handler(fd, NULL, NULL, NULL, NULL);
107 break;
108 }
109
110 return 0;
111 }
112
113 static size_t curl_size_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
114 {
115 CURLState *s = ((CURLState*)opaque);
116 size_t realsize = size * nmemb;
117 size_t fsize;
118
119 if(sscanf(ptr, "Content-Length: %zd", &fsize) == 1) {
120 s->s->len = fsize;
121 }
122
123 return realsize;
124 }
125
126 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
127 {
128 CURLState *s = ((CURLState*)opaque);
129 size_t realsize = size * nmemb;
130 int i;
131
132 DPRINTF("CURL: Just reading %zd bytes\n", realsize);
133
134 if (!s || !s->orig_buf)
135 goto read_end;
136
137 memcpy(s->orig_buf + s->buf_off, ptr, realsize);
138 s->buf_off += realsize;
139
140 for(i=0; i<CURL_NUM_ACB; i++) {
141 CURLAIOCB *acb = s->acb[i];
142
143 if (!acb)
144 continue;
145
146 if ((s->buf_off >= acb->end)) {
147 qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
148 acb->end - acb->start);
149 acb->common.cb(acb->common.opaque, 0);
150 qemu_aio_release(acb);
151 s->acb[i] = NULL;
152 }
153 }
154
155 read_end:
156 return realsize;
157 }
158
159 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
160 CURLAIOCB *acb)
161 {
162 int i;
163 size_t end = start + len;
164
165 for (i=0; i<CURL_NUM_STATES; i++) {
166 CURLState *state = &s->states[i];
167 size_t buf_end = (state->buf_start + state->buf_off);
168 size_t buf_fend = (state->buf_start + state->buf_len);
169
170 if (!state->orig_buf)
171 continue;
172 if (!state->buf_off)
173 continue;
174
175 // Does the existing buffer cover our section?
176 if ((start >= state->buf_start) &&
177 (start <= buf_end) &&
178 (end >= state->buf_start) &&
179 (end <= buf_end))
180 {
181 char *buf = state->orig_buf + (start - state->buf_start);
182
183 qemu_iovec_from_buf(acb->qiov, 0, buf, len);
184 acb->common.cb(acb->common.opaque, 0);
185
186 return FIND_RET_OK;
187 }
188
189 // Wait for unfinished chunks
190 if ((start >= state->buf_start) &&
191 (start <= buf_fend) &&
192 (end >= state->buf_start) &&
193 (end <= buf_fend))
194 {
195 int j;
196
197 acb->start = start - state->buf_start;
198 acb->end = acb->start + len;
199
200 for (j=0; j<CURL_NUM_ACB; j++) {
201 if (!state->acb[j]) {
202 state->acb[j] = acb;
203 return FIND_RET_WAIT;
204 }
205 }
206 }
207 }
208
209 return FIND_RET_NONE;
210 }
211
212 static void curl_multi_do(void *arg)
213 {
214 BDRVCURLState *s = (BDRVCURLState *)arg;
215 int running;
216 int r;
217 int msgs_in_queue;
218
219 if (!s->multi)
220 return;
221
222 do {
223 r = curl_multi_socket_all(s->multi, &running);
224 } while(r == CURLM_CALL_MULTI_PERFORM);
225
226 /* Try to find done transfers, so we can free the easy
227 * handle again. */
228 do {
229 CURLMsg *msg;
230 msg = curl_multi_info_read(s->multi, &msgs_in_queue);
231
232 if (!msg)
233 break;
234 if (msg->msg == CURLMSG_NONE)
235 break;
236
237 switch (msg->msg) {
238 case CURLMSG_DONE:
239 {
240 CURLState *state = NULL;
241 curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE, (char**)&state);
242
243 /* ACBs for successful messages get completed in curl_read_cb */
244 if (msg->data.result != CURLE_OK) {
245 int i;
246 for (i = 0; i < CURL_NUM_ACB; i++) {
247 CURLAIOCB *acb = state->acb[i];
248
249 if (acb == NULL) {
250 continue;
251 }
252
253 acb->common.cb(acb->common.opaque, -EIO);
254 qemu_aio_release(acb);
255 state->acb[i] = NULL;
256 }
257 }
258
259 curl_clean_state(state);
260 break;
261 }
262 default:
263 msgs_in_queue = 0;
264 break;
265 }
266 } while(msgs_in_queue);
267 }
268
269 static CURLState *curl_init_state(BDRVCURLState *s)
270 {
271 CURLState *state = NULL;
272 int i, j;
273
274 do {
275 for (i=0; i<CURL_NUM_STATES; i++) {
276 for (j=0; j<CURL_NUM_ACB; j++)
277 if (s->states[i].acb[j])
278 continue;
279 if (s->states[i].in_use)
280 continue;
281
282 state = &s->states[i];
283 state->in_use = 1;
284 break;
285 }
286 if (!state) {
287 g_usleep(100);
288 curl_multi_do(s);
289 }
290 } while(!state);
291
292 if (state->curl)
293 goto has_curl;
294
295 state->curl = curl_easy_init();
296 if (!state->curl)
297 return NULL;
298 curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
299 curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, 5);
300 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
301 curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
302 curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
303 curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
304 curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
305 curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
306 curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
307 curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
308
309 /* Restrict supported protocols to avoid security issues in the more
310 * obscure protocols. For example, do not allow POP3/SMTP/IMAP see
311 * CVE-2013-0249.
312 *
313 * Restricting protocols is only supported from 7.19.4 upwards.
314 */
315 #if LIBCURL_VERSION_NUM >= 0x071304
316 curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
317 curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
318 #endif
319
320 #ifdef DEBUG_VERBOSE
321 curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
322 #endif
323
324 has_curl:
325
326 state->s = s;
327
328 return state;
329 }
330
331 static void curl_clean_state(CURLState *s)
332 {
333 if (s->s->multi)
334 curl_multi_remove_handle(s->s->multi, s->curl);
335 s->in_use = 0;
336 }
337
338 static void curl_parse_filename(const char *filename, QDict *options,
339 Error **errp)
340 {
341
342 #define RA_OPTSTR ":readahead="
343 char *file;
344 char *ra;
345 const char *ra_val;
346 int parse_state = 0;
347
348 file = g_strdup(filename);
349
350 /* Parse a trailing ":readahead=#:" param, if present. */
351 ra = file + strlen(file) - 1;
352 while (ra >= file) {
353 if (parse_state == 0) {
354 if (*ra == ':') {
355 parse_state++;
356 } else {
357 break;
358 }
359 } else if (parse_state == 1) {
360 if (*ra > '9' || *ra < '0') {
361 char *opt_start = ra - strlen(RA_OPTSTR) + 1;
362 if (opt_start > file &&
363 strncmp(opt_start, RA_OPTSTR, strlen(RA_OPTSTR)) == 0) {
364 ra_val = ra + 1;
365 ra -= strlen(RA_OPTSTR) - 1;
366 *ra = '\0';
367 qdict_put(options, "readahead", qstring_from_str(ra_val));
368 }
369 break;
370 }
371 }
372 ra--;
373 }
374
375 qdict_put(options, "url", qstring_from_str(file));
376
377 g_free(file);
378 }
379
380 static QemuOptsList runtime_opts = {
381 .name = "curl",
382 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
383 .desc = {
384 {
385 .name = "url",
386 .type = QEMU_OPT_STRING,
387 .help = "URL to open",
388 },
389 {
390 .name = "readahead",
391 .type = QEMU_OPT_SIZE,
392 .help = "Readahead size",
393 },
394 { /* end of list */ }
395 },
396 };
397
398 static int curl_open(BlockDriverState *bs, QDict *options, int flags)
399 {
400 BDRVCURLState *s = bs->opaque;
401 CURLState *state = NULL;
402 QemuOpts *opts;
403 Error *local_err = NULL;
404 const char *file;
405 double d;
406
407 static int inited = 0;
408
409 opts = qemu_opts_create_nofail(&runtime_opts);
410 qemu_opts_absorb_qdict(opts, options, &local_err);
411 if (error_is_set(&local_err)) {
412 qerror_report_err(local_err);
413 error_free(local_err);
414 goto out_noclean;
415 }
416
417 s->readahead_size = qemu_opt_get_size(opts, "readahead", READ_AHEAD_SIZE);
418 if ((s->readahead_size & 0x1ff) != 0) {
419 fprintf(stderr, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512\n",
420 s->readahead_size);
421 goto out_noclean;
422 }
423
424 file = qemu_opt_get(opts, "url");
425 if (file == NULL) {
426 qerror_report(ERROR_CLASS_GENERIC_ERROR, "curl block driver requires "
427 "an 'url' option");
428 goto out_noclean;
429 }
430
431 if (!inited) {
432 curl_global_init(CURL_GLOBAL_ALL);
433 inited = 1;
434 }
435
436 DPRINTF("CURL: Opening %s\n", file);
437 s->url = g_strdup(file);
438 state = curl_init_state(s);
439 if (!state)
440 goto out_noclean;
441
442 // Get file size
443
444 curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
445 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_size_cb);
446 if (curl_easy_perform(state->curl))
447 goto out;
448 curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
449 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
450 curl_easy_setopt(state->curl, CURLOPT_NOBODY, 0);
451 if (d)
452 s->len = (size_t)d;
453 else if(!s->len)
454 goto out;
455 DPRINTF("CURL: Size = %zd\n", s->len);
456
457 curl_clean_state(state);
458 curl_easy_cleanup(state->curl);
459 state->curl = NULL;
460
461 // Now we know the file exists and its size, so let's
462 // initialize the multi interface!
463
464 s->multi = curl_multi_init();
465 curl_multi_setopt( s->multi, CURLMOPT_SOCKETDATA, s);
466 curl_multi_setopt( s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb );
467 curl_multi_do(s);
468
469 qemu_opts_del(opts);
470 return 0;
471
472 out:
473 fprintf(stderr, "CURL: Error opening file: %s\n", state->errmsg);
474 curl_easy_cleanup(state->curl);
475 state->curl = NULL;
476 out_noclean:
477 g_free(s->url);
478 qemu_opts_del(opts);
479 return -EINVAL;
480 }
481
482 static int curl_aio_flush(void *opaque)
483 {
484 BDRVCURLState *s = opaque;
485 int i, j;
486
487 for (i=0; i < CURL_NUM_STATES; i++) {
488 for(j=0; j < CURL_NUM_ACB; j++) {
489 if (s->states[i].acb[j]) {
490 return 1;
491 }
492 }
493 }
494 return 0;
495 }
496
497 static void curl_aio_cancel(BlockDriverAIOCB *blockacb)
498 {
499 // Do we have to implement canceling? Seems to work without...
500 }
501
502 static const AIOCBInfo curl_aiocb_info = {
503 .aiocb_size = sizeof(CURLAIOCB),
504 .cancel = curl_aio_cancel,
505 };
506
507
508 static void curl_readv_bh_cb(void *p)
509 {
510 CURLState *state;
511
512 CURLAIOCB *acb = p;
513 BDRVCURLState *s = acb->common.bs->opaque;
514
515 qemu_bh_delete(acb->bh);
516 acb->bh = NULL;
517
518 size_t start = acb->sector_num * SECTOR_SIZE;
519 size_t end;
520
521 // In case we have the requested data already (e.g. read-ahead),
522 // we can just call the callback and be done.
523 switch (curl_find_buf(s, start, acb->nb_sectors * SECTOR_SIZE, acb)) {
524 case FIND_RET_OK:
525 qemu_aio_release(acb);
526 // fall through
527 case FIND_RET_WAIT:
528 return;
529 default:
530 break;
531 }
532
533 // No cache found, so let's start a new request
534 state = curl_init_state(s);
535 if (!state) {
536 acb->common.cb(acb->common.opaque, -EIO);
537 qemu_aio_release(acb);
538 return;
539 }
540
541 acb->start = 0;
542 acb->end = (acb->nb_sectors * SECTOR_SIZE);
543
544 state->buf_off = 0;
545 if (state->orig_buf)
546 g_free(state->orig_buf);
547 state->buf_start = start;
548 state->buf_len = acb->end + s->readahead_size;
549 end = MIN(start + state->buf_len, s->len) - 1;
550 state->orig_buf = g_malloc(state->buf_len);
551 state->acb[0] = acb;
552
553 snprintf(state->range, 127, "%zd-%zd", start, end);
554 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
555 (acb->nb_sectors * SECTOR_SIZE), start, state->range);
556 curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
557
558 curl_multi_add_handle(s->multi, state->curl);
559 curl_multi_do(s);
560
561 }
562
563 static BlockDriverAIOCB *curl_aio_readv(BlockDriverState *bs,
564 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
565 BlockDriverCompletionFunc *cb, void *opaque)
566 {
567 CURLAIOCB *acb;
568
569 acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
570
571 acb->qiov = qiov;
572 acb->sector_num = sector_num;
573 acb->nb_sectors = nb_sectors;
574
575 acb->bh = qemu_bh_new(curl_readv_bh_cb, acb);
576
577 if (!acb->bh) {
578 DPRINTF("CURL: qemu_bh_new failed\n");
579 return NULL;
580 }
581
582 qemu_bh_schedule(acb->bh);
583 return &acb->common;
584 }
585
586 static void curl_close(BlockDriverState *bs)
587 {
588 BDRVCURLState *s = bs->opaque;
589 int i;
590
591 DPRINTF("CURL: Close\n");
592 for (i=0; i<CURL_NUM_STATES; i++) {
593 if (s->states[i].in_use)
594 curl_clean_state(&s->states[i]);
595 if (s->states[i].curl) {
596 curl_easy_cleanup(s->states[i].curl);
597 s->states[i].curl = NULL;
598 }
599 if (s->states[i].orig_buf) {
600 g_free(s->states[i].orig_buf);
601 s->states[i].orig_buf = NULL;
602 }
603 }
604 if (s->multi)
605 curl_multi_cleanup(s->multi);
606 g_free(s->url);
607 }
608
609 static int64_t curl_getlength(BlockDriverState *bs)
610 {
611 BDRVCURLState *s = bs->opaque;
612 return s->len;
613 }
614
615 static BlockDriver bdrv_http = {
616 .format_name = "http",
617 .protocol_name = "http",
618
619 .instance_size = sizeof(BDRVCURLState),
620 .bdrv_parse_filename = curl_parse_filename,
621 .bdrv_file_open = curl_open,
622 .bdrv_close = curl_close,
623 .bdrv_getlength = curl_getlength,
624
625 .bdrv_aio_readv = curl_aio_readv,
626 };
627
628 static BlockDriver bdrv_https = {
629 .format_name = "https",
630 .protocol_name = "https",
631
632 .instance_size = sizeof(BDRVCURLState),
633 .bdrv_parse_filename = curl_parse_filename,
634 .bdrv_file_open = curl_open,
635 .bdrv_close = curl_close,
636 .bdrv_getlength = curl_getlength,
637
638 .bdrv_aio_readv = curl_aio_readv,
639 };
640
641 static BlockDriver bdrv_ftp = {
642 .format_name = "ftp",
643 .protocol_name = "ftp",
644
645 .instance_size = sizeof(BDRVCURLState),
646 .bdrv_parse_filename = curl_parse_filename,
647 .bdrv_file_open = curl_open,
648 .bdrv_close = curl_close,
649 .bdrv_getlength = curl_getlength,
650
651 .bdrv_aio_readv = curl_aio_readv,
652 };
653
654 static BlockDriver bdrv_ftps = {
655 .format_name = "ftps",
656 .protocol_name = "ftps",
657
658 .instance_size = sizeof(BDRVCURLState),
659 .bdrv_parse_filename = curl_parse_filename,
660 .bdrv_file_open = curl_open,
661 .bdrv_close = curl_close,
662 .bdrv_getlength = curl_getlength,
663
664 .bdrv_aio_readv = curl_aio_readv,
665 };
666
667 static BlockDriver bdrv_tftp = {
668 .format_name = "tftp",
669 .protocol_name = "tftp",
670
671 .instance_size = sizeof(BDRVCURLState),
672 .bdrv_parse_filename = curl_parse_filename,
673 .bdrv_file_open = curl_open,
674 .bdrv_close = curl_close,
675 .bdrv_getlength = curl_getlength,
676
677 .bdrv_aio_readv = curl_aio_readv,
678 };
679
680 static void curl_block_init(void)
681 {
682 bdrv_register(&bdrv_http);
683 bdrv_register(&bdrv_https);
684 bdrv_register(&bdrv_ftp);
685 bdrv_register(&bdrv_ftps);
686 bdrv_register(&bdrv_tftp);
687 }
688
689 block_init(curl_block_init);