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
25 #include "qemu/osdep.h"
26 #include "qapi/error.h"
27 #include "qemu/error-report.h"
28 #include "qemu/module.h"
29 #include "qemu/option.h"
30 #include "block/block-io.h"
31 #include "block/block_int.h"
32 #include "qapi/qmp/qdict.h"
33 #include "qapi/qmp/qstring.h"
34 #include "crypto/secret.h"
35 #include <curl/curl.h>
36 #include "qemu/cutils.h"
37 #include "trace.h"
38
39 // #define DEBUG_VERBOSE
40
41 /* CURL 7.85.0 switches to a string based API for specifying
42 * the desired protocols.
43 */
44 #if LIBCURL_VERSION_NUM >= 0x075500
45 #define PROTOCOLS "HTTP,HTTPS,FTP,FTPS"
46 #else
47 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
48 CURLPROTO_FTP | CURLPROTO_FTPS)
49 #endif
50
51 #define CURL_NUM_STATES 8
52 #define CURL_NUM_ACB 8
53 #define CURL_TIMEOUT_MAX 10000
54
55 #define CURL_BLOCK_OPT_URL "url"
56 #define CURL_BLOCK_OPT_READAHEAD "readahead"
57 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
58 #define CURL_BLOCK_OPT_TIMEOUT "timeout"
59 #define CURL_BLOCK_OPT_COOKIE "cookie"
60 #define CURL_BLOCK_OPT_COOKIE_SECRET "cookie-secret"
61 #define CURL_BLOCK_OPT_USERNAME "username"
62 #define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
63 #define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
64 #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
65
66 #define CURL_BLOCK_OPT_READAHEAD_DEFAULT (256 * 1024)
67 #define CURL_BLOCK_OPT_SSLVERIFY_DEFAULT true
68 #define CURL_BLOCK_OPT_TIMEOUT_DEFAULT 5
69
70 struct BDRVCURLState;
71 struct CURLState;
72
73 static bool libcurl_initialized;
74
75 typedef struct CURLAIOCB {
76 Coroutine *co;
77 QEMUIOVector *qiov;
78
79 uint64_t offset;
80 uint64_t bytes;
81 int ret;
82
83 size_t start;
84 size_t end;
85 } CURLAIOCB;
86
87 typedef struct CURLSocket {
88 int fd;
89 struct BDRVCURLState *s;
90 } CURLSocket;
91
92 typedef struct CURLState
93 {
94 struct BDRVCURLState *s;
95 CURLAIOCB *acb[CURL_NUM_ACB];
96 CURL *curl;
97 char *orig_buf;
98 uint64_t buf_start;
99 size_t buf_off;
100 size_t buf_len;
101 char range[128];
102 char errmsg[CURL_ERROR_SIZE];
103 char in_use;
104 } CURLState;
105
106 typedef struct BDRVCURLState {
107 CURLM *multi;
108 QEMUTimer timer;
109 uint64_t len;
110 CURLState states[CURL_NUM_STATES];
111 GHashTable *sockets; /* GINT_TO_POINTER(fd) -> socket */
112 char *url;
113 size_t readahead_size;
114 bool sslverify;
115 uint64_t timeout;
116 char *cookie;
117 bool accept_range;
118 AioContext *aio_context;
119 QemuMutex mutex;
120 CoQueue free_state_waitq;
121 char *username;
122 char *password;
123 char *proxyusername;
124 char *proxypassword;
125 } BDRVCURLState;
126
127 static void curl_clean_state(CURLState *s);
128 static void curl_multi_do(void *arg);
129
curl_drop_socket(void * key,void * value,void * opaque)130 static gboolean curl_drop_socket(void *key, void *value, void *opaque)
131 {
132 CURLSocket *socket = value;
133 BDRVCURLState *s = socket->s;
134
135 aio_set_fd_handler(s->aio_context, socket->fd,
136 NULL, NULL, NULL, NULL, NULL);
137 return true;
138 }
139
curl_drop_all_sockets(GHashTable * sockets)140 static void curl_drop_all_sockets(GHashTable *sockets)
141 {
142 g_hash_table_foreach_remove(sockets, curl_drop_socket, NULL);
143 }
144
145 /* Called from curl_multi_do_locked, with s->mutex held. */
curl_timer_cb(CURLM * multi,long timeout_ms,void * opaque)146 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
147 {
148 BDRVCURLState *s = opaque;
149
150 trace_curl_timer_cb(timeout_ms);
151 if (timeout_ms == -1) {
152 timer_del(&s->timer);
153 } else {
154 int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
155 timer_mod(&s->timer,
156 qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
157 }
158 return 0;
159 }
160
161 /* Called from curl_multi_do_locked, with s->mutex held. */
curl_sock_cb(CURL * curl,curl_socket_t fd,int action,void * userp,void * sp)162 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
163 void *userp, void *sp)
164 {
165 BDRVCURLState *s;
166 CURLState *state = NULL;
167 CURLSocket *socket;
168
169 curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
170 s = state->s;
171
172 socket = g_hash_table_lookup(s->sockets, GINT_TO_POINTER(fd));
173 if (!socket) {
174 socket = g_new0(CURLSocket, 1);
175 socket->fd = fd;
176 socket->s = s;
177 g_hash_table_insert(s->sockets, GINT_TO_POINTER(fd), socket);
178 }
179
180 trace_curl_sock_cb(action, (int)fd);
181 switch (action) {
182 case CURL_POLL_IN:
183 aio_set_fd_handler(s->aio_context, fd,
184 curl_multi_do, NULL, NULL, NULL, socket);
185 break;
186 case CURL_POLL_OUT:
187 aio_set_fd_handler(s->aio_context, fd,
188 NULL, curl_multi_do, NULL, NULL, socket);
189 break;
190 case CURL_POLL_INOUT:
191 aio_set_fd_handler(s->aio_context, fd,
192 curl_multi_do, curl_multi_do,
193 NULL, NULL, socket);
194 break;
195 case CURL_POLL_REMOVE:
196 aio_set_fd_handler(s->aio_context, fd,
197 NULL, NULL, NULL, NULL, NULL);
198 break;
199 }
200
201 if (action == CURL_POLL_REMOVE) {
202 g_hash_table_remove(s->sockets, GINT_TO_POINTER(fd));
203 }
204
205 return 0;
206 }
207
208 /* Called from curl_multi_do_locked, with s->mutex held. */
curl_header_cb(void * ptr,size_t size,size_t nmemb,void * opaque)209 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
210 {
211 BDRVCURLState *s = opaque;
212 size_t realsize = size * nmemb;
213 const char *p = ptr;
214 const char *end = p + realsize;
215 const char *t = "accept-ranges : bytes "; /* A lowercase template */
216
217 /* check if header matches the "t" template */
218 for (;;) {
219 if (*t == ' ') { /* space in t matches any amount of isspace in p */
220 if (p < end && g_ascii_isspace(*p)) {
221 ++p;
222 } else {
223 ++t;
224 }
225 } else if (*t && p < end && *t == g_ascii_tolower(*p)) {
226 ++p, ++t;
227 } else {
228 break;
229 }
230 }
231
232 if (!*t && p == end) { /* if we managed to reach ends of both strings */
233 s->accept_range = true;
234 }
235
236 return realsize;
237 }
238
239 /* Called from curl_multi_do_locked, with s->mutex held. */
curl_read_cb(void * ptr,size_t size,size_t nmemb,void * opaque)240 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
241 {
242 CURLState *s = ((CURLState*)opaque);
243 size_t realsize = size * nmemb;
244
245 trace_curl_read_cb(realsize);
246
247 if (!s || !s->orig_buf) {
248 goto read_end;
249 }
250
251 if (s->buf_off >= s->buf_len) {
252 /* buffer full, read nothing */
253 goto read_end;
254 }
255 realsize = MIN(realsize, s->buf_len - s->buf_off);
256 memcpy(s->orig_buf + s->buf_off, ptr, realsize);
257 s->buf_off += realsize;
258
259 read_end:
260 /* curl will error out if we do not return this value */
261 return size * nmemb;
262 }
263
264 /* Called with s->mutex held. */
curl_find_buf(BDRVCURLState * s,uint64_t start,uint64_t len,CURLAIOCB * acb)265 static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
266 CURLAIOCB *acb)
267 {
268 int i;
269 uint64_t end = start + len;
270 uint64_t clamped_end = MIN(end, s->len);
271 uint64_t clamped_len = clamped_end - start;
272
273 for (i=0; i<CURL_NUM_STATES; i++) {
274 CURLState *state = &s->states[i];
275 uint64_t buf_end = (state->buf_start + state->buf_off);
276 uint64_t buf_fend = (state->buf_start + state->buf_len);
277
278 if (!state->orig_buf)
279 continue;
280 if (!state->buf_off)
281 continue;
282
283 // Does the existing buffer cover our section?
284 if ((start >= state->buf_start) &&
285 (start <= buf_end) &&
286 (clamped_end >= state->buf_start) &&
287 (clamped_end <= buf_end))
288 {
289 char *buf = state->orig_buf + (start - state->buf_start);
290
291 qemu_iovec_from_buf(acb->qiov, 0, buf, clamped_len);
292 if (clamped_len < len) {
293 qemu_iovec_memset(acb->qiov, clamped_len, 0, len - clamped_len);
294 }
295 acb->ret = 0;
296 return true;
297 }
298
299 // Wait for unfinished chunks
300 if (state->in_use &&
301 (start >= state->buf_start) &&
302 (start <= buf_fend) &&
303 (clamped_end >= state->buf_start) &&
304 (clamped_end <= buf_fend))
305 {
306 int j;
307
308 acb->start = start - state->buf_start;
309 acb->end = acb->start + clamped_len;
310
311 for (j=0; j<CURL_NUM_ACB; j++) {
312 if (!state->acb[j]) {
313 state->acb[j] = acb;
314 return true;
315 }
316 }
317 }
318 }
319
320 return false;
321 }
322
323 /* Called with s->mutex held. */
curl_multi_check_completion(BDRVCURLState * s)324 static void curl_multi_check_completion(BDRVCURLState *s)
325 {
326 int msgs_in_queue;
327
328 /* Try to find done transfers, so we can free the easy
329 * handle again. */
330 for (;;) {
331 CURLMsg *msg;
332 msg = curl_multi_info_read(s->multi, &msgs_in_queue);
333
334 /* Quit when there are no more completions */
335 if (!msg)
336 break;
337
338 if (msg->msg == CURLMSG_DONE) {
339 int i;
340 CURLState *state = NULL;
341 bool error = msg->data.result != CURLE_OK;
342
343 curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
344 (char **)&state);
345
346 if (error) {
347 static int errcount = 100;
348
349 /* Don't lose the original error message from curl, since
350 * it contains extra data.
351 */
352 if (errcount > 0) {
353 error_report("curl: %s", state->errmsg);
354 if (--errcount == 0) {
355 error_report("curl: further errors suppressed");
356 }
357 }
358 }
359
360 for (i = 0; i < CURL_NUM_ACB; i++) {
361 CURLAIOCB *acb = state->acb[i];
362
363 if (acb == NULL) {
364 continue;
365 }
366
367 if (!error) {
368 /* Assert that we have read all data */
369 assert(state->buf_off >= acb->end);
370
371 qemu_iovec_from_buf(acb->qiov, 0,
372 state->orig_buf + acb->start,
373 acb->end - acb->start);
374
375 if (acb->end - acb->start < acb->bytes) {
376 size_t offset = acb->end - acb->start;
377 qemu_iovec_memset(acb->qiov, offset, 0,
378 acb->bytes - offset);
379 }
380 }
381
382 acb->ret = error ? -EIO : 0;
383 state->acb[i] = NULL;
384 qemu_mutex_unlock(&s->mutex);
385 aio_co_wake(acb->co);
386 qemu_mutex_lock(&s->mutex);
387 }
388
389 curl_clean_state(state);
390 break;
391 }
392 }
393 }
394
395 /* Called with s->mutex held. */
curl_multi_do_locked(CURLSocket * socket)396 static void curl_multi_do_locked(CURLSocket *socket)
397 {
398 BDRVCURLState *s = socket->s;
399 int running;
400 int r;
401
402 if (!s->multi) {
403 return;
404 }
405
406 do {
407 r = curl_multi_socket_action(s->multi, socket->fd, 0, &running);
408 } while (r == CURLM_CALL_MULTI_PERFORM);
409 }
410
curl_multi_do(void * arg)411 static void curl_multi_do(void *arg)
412 {
413 CURLSocket *socket = arg;
414 BDRVCURLState *s = socket->s;
415
416 qemu_mutex_lock(&s->mutex);
417 curl_multi_do_locked(socket);
418 curl_multi_check_completion(s);
419 qemu_mutex_unlock(&s->mutex);
420 }
421
curl_multi_timeout_do(void * arg)422 static void curl_multi_timeout_do(void *arg)
423 {
424 BDRVCURLState *s = (BDRVCURLState *)arg;
425 int running;
426
427 if (!s->multi) {
428 return;
429 }
430
431 qemu_mutex_lock(&s->mutex);
432 curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
433
434 curl_multi_check_completion(s);
435 qemu_mutex_unlock(&s->mutex);
436 }
437
438 /* Called with s->mutex held. */
curl_find_state(BDRVCURLState * s)439 static CURLState *curl_find_state(BDRVCURLState *s)
440 {
441 CURLState *state = NULL;
442 int i;
443
444 for (i = 0; i < CURL_NUM_STATES; i++) {
445 if (!s->states[i].in_use) {
446 state = &s->states[i];
447 state->in_use = 1;
448 break;
449 }
450 }
451 return state;
452 }
453
curl_init_state(BDRVCURLState * s,CURLState * state)454 static int curl_init_state(BDRVCURLState *s, CURLState *state)
455 {
456 if (!state->curl) {
457 state->curl = curl_easy_init();
458 if (!state->curl) {
459 return -EIO;
460 }
461 if (curl_easy_setopt(state->curl, CURLOPT_URL, s->url) ||
462 curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
463 (long) s->sslverify) ||
464 curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYHOST,
465 s->sslverify ? 2L : 0L)) {
466 goto err;
467 }
468 if (s->cookie) {
469 if (curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie)) {
470 goto err;
471 }
472 }
473 if (curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout) ||
474 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
475 (void *)curl_read_cb) ||
476 curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state) ||
477 curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state) ||
478 curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1) ||
479 curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1) ||
480 curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1) ||
481 curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg) ||
482 curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1)) {
483 goto err;
484 }
485 if (s->username) {
486 if (curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username)) {
487 goto err;
488 }
489 }
490 if (s->password) {
491 if (curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password)) {
492 goto err;
493 }
494 }
495 if (s->proxyusername) {
496 if (curl_easy_setopt(state->curl,
497 CURLOPT_PROXYUSERNAME, s->proxyusername)) {
498 goto err;
499 }
500 }
501 if (s->proxypassword) {
502 if (curl_easy_setopt(state->curl,
503 CURLOPT_PROXYPASSWORD, s->proxypassword)) {
504 goto err;
505 }
506 }
507
508 /* Restrict supported protocols to avoid security issues in the more
509 * obscure protocols. For example, do not allow POP3/SMTP/IMAP see
510 * CVE-2013-0249.
511 *
512 * Restricting protocols is only supported from 7.19.4 upwards. Note:
513 * version 7.85.0 deprecates CURLOPT_*PROTOCOLS in favour of a string
514 * based CURLOPT_*PROTOCOLS_STR API.
515 */
516 #if LIBCURL_VERSION_NUM >= 0x075500
517 if (curl_easy_setopt(state->curl,
518 CURLOPT_PROTOCOLS_STR, PROTOCOLS) ||
519 curl_easy_setopt(state->curl,
520 CURLOPT_REDIR_PROTOCOLS_STR, PROTOCOLS)) {
521 goto err;
522 }
523 #elif LIBCURL_VERSION_NUM >= 0x071304
524 if (curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS) ||
525 curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS)) {
526 goto err;
527 }
528 #endif
529
530 #ifdef DEBUG_VERBOSE
531 if (curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1)) {
532 goto err;
533 }
534 #endif
535 }
536
537 state->s = s;
538
539 return 0;
540
541 err:
542 curl_easy_cleanup(state->curl);
543 state->curl = NULL;
544 return -EIO;
545 }
546
547 /* Called with s->mutex held. */
curl_clean_state(CURLState * s)548 static void curl_clean_state(CURLState *s)
549 {
550 int j;
551 for (j = 0; j < CURL_NUM_ACB; j++) {
552 assert(!s->acb[j]);
553 }
554
555 if (s->s->multi)
556 curl_multi_remove_handle(s->s->multi, s->curl);
557
558 s->in_use = 0;
559
560 qemu_co_enter_next(&s->s->free_state_waitq, &s->s->mutex);
561 }
562
curl_parse_filename(const char * filename,QDict * options,Error ** errp)563 static void curl_parse_filename(const char *filename, QDict *options,
564 Error **errp)
565 {
566 qdict_put_str(options, CURL_BLOCK_OPT_URL, filename);
567 }
568
curl_detach_aio_context(BlockDriverState * bs)569 static void curl_detach_aio_context(BlockDriverState *bs)
570 {
571 BDRVCURLState *s = bs->opaque;
572 int i;
573
574 WITH_QEMU_LOCK_GUARD(&s->mutex) {
575 curl_drop_all_sockets(s->sockets);
576 for (i = 0; i < CURL_NUM_STATES; i++) {
577 if (s->states[i].in_use) {
578 curl_clean_state(&s->states[i]);
579 }
580 if (s->states[i].curl) {
581 curl_easy_cleanup(s->states[i].curl);
582 s->states[i].curl = NULL;
583 }
584 g_free(s->states[i].orig_buf);
585 s->states[i].orig_buf = NULL;
586 }
587 if (s->multi) {
588 curl_multi_cleanup(s->multi);
589 s->multi = NULL;
590 }
591 }
592
593 timer_del(&s->timer);
594 }
595
curl_attach_aio_context(BlockDriverState * bs,AioContext * new_context)596 static void curl_attach_aio_context(BlockDriverState *bs,
597 AioContext *new_context)
598 {
599 BDRVCURLState *s = bs->opaque;
600
601 aio_timer_init(new_context, &s->timer,
602 QEMU_CLOCK_REALTIME, SCALE_NS,
603 curl_multi_timeout_do, s);
604
605 assert(!s->multi);
606 s->multi = curl_multi_init();
607 s->aio_context = new_context;
608 curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
609 curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
610 curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
611 }
612
613 static QemuOptsList runtime_opts = {
614 .name = "curl",
615 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
616 .desc = {
617 {
618 .name = CURL_BLOCK_OPT_URL,
619 .type = QEMU_OPT_STRING,
620 .help = "URL to open",
621 },
622 {
623 .name = CURL_BLOCK_OPT_READAHEAD,
624 .type = QEMU_OPT_SIZE,
625 .help = "Readahead size",
626 },
627 {
628 .name = CURL_BLOCK_OPT_SSLVERIFY,
629 .type = QEMU_OPT_BOOL,
630 .help = "Verify SSL certificate"
631 },
632 {
633 .name = CURL_BLOCK_OPT_TIMEOUT,
634 .type = QEMU_OPT_NUMBER,
635 .help = "Curl timeout"
636 },
637 {
638 .name = CURL_BLOCK_OPT_COOKIE,
639 .type = QEMU_OPT_STRING,
640 .help = "Pass the cookie or list of cookies with each request"
641 },
642 {
643 .name = CURL_BLOCK_OPT_COOKIE_SECRET,
644 .type = QEMU_OPT_STRING,
645 .help = "ID of secret used as cookie passed with each request"
646 },
647 {
648 .name = CURL_BLOCK_OPT_USERNAME,
649 .type = QEMU_OPT_STRING,
650 .help = "Username for HTTP auth"
651 },
652 {
653 .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
654 .type = QEMU_OPT_STRING,
655 .help = "ID of secret used as password for HTTP auth",
656 },
657 {
658 .name = CURL_BLOCK_OPT_PROXY_USERNAME,
659 .type = QEMU_OPT_STRING,
660 .help = "Username for HTTP proxy auth"
661 },
662 {
663 .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
664 .type = QEMU_OPT_STRING,
665 .help = "ID of secret used as password for HTTP proxy auth",
666 },
667 { /* end of list */ }
668 },
669 };
670
671
curl_open(BlockDriverState * bs,QDict * options,int flags,Error ** errp)672 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
673 Error **errp)
674 {
675 BDRVCURLState *s = bs->opaque;
676 CURLState *state = NULL;
677 QemuOpts *opts;
678 const char *file;
679 const char *cookie;
680 const char *cookie_secret;
681 /* CURL >= 7.55.0 uses curl_off_t for content length instead of a double */
682 #if LIBCURL_VERSION_NUM >= 0x073700
683 curl_off_t cl;
684 #else
685 double cl;
686 #endif
687 const char *secretid;
688 const char *protocol_delimiter;
689 int ret;
690
691 bdrv_graph_rdlock_main_loop();
692 ret = bdrv_apply_auto_read_only(bs, "curl driver does not support writes",
693 errp);
694 bdrv_graph_rdunlock_main_loop();
695 if (ret < 0) {
696 return ret;
697 }
698
699 if (!libcurl_initialized) {
700 ret = curl_global_init(CURL_GLOBAL_ALL);
701 if (ret) {
702 error_setg(errp, "libcurl initialization failed with %d", ret);
703 return -EIO;
704 }
705 libcurl_initialized = true;
706 }
707
708 qemu_mutex_init(&s->mutex);
709 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
710 if (!qemu_opts_absorb_qdict(opts, options, errp)) {
711 goto out_noclean;
712 }
713
714 s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
715 CURL_BLOCK_OPT_READAHEAD_DEFAULT);
716 if ((s->readahead_size & 0x1ff) != 0) {
717 error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
718 s->readahead_size);
719 goto out_noclean;
720 }
721
722 s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
723 CURL_BLOCK_OPT_TIMEOUT_DEFAULT);
724 if (s->timeout > CURL_TIMEOUT_MAX) {
725 error_setg(errp, "timeout parameter is too large or negative");
726 goto out_noclean;
727 }
728
729 s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY,
730 CURL_BLOCK_OPT_SSLVERIFY_DEFAULT);
731
732 cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
733 cookie_secret = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE_SECRET);
734
735 if (cookie && cookie_secret) {
736 error_setg(errp,
737 "curl driver cannot handle both cookie and cookie secret");
738 goto out_noclean;
739 }
740
741 if (cookie_secret) {
742 s->cookie = qcrypto_secret_lookup_as_utf8(cookie_secret, errp);
743 if (!s->cookie) {
744 goto out_noclean;
745 }
746 } else {
747 s->cookie = g_strdup(cookie);
748 }
749
750 file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
751 if (file == NULL) {
752 error_setg(errp, "curl block driver requires an 'url' option");
753 goto out_noclean;
754 }
755
756 if (!strstart(file, bs->drv->protocol_name, &protocol_delimiter) ||
757 !strstart(protocol_delimiter, "://", NULL))
758 {
759 error_setg(errp, "%s curl driver cannot handle the URL '%s' (does not "
760 "start with '%s://')", bs->drv->protocol_name, file,
761 bs->drv->protocol_name);
762 goto out_noclean;
763 }
764
765 s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
766 secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
767
768 if (secretid) {
769 s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
770 if (!s->password) {
771 goto out_noclean;
772 }
773 }
774
775 s->proxyusername = g_strdup(
776 qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
777 secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
778 if (secretid) {
779 s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
780 if (!s->proxypassword) {
781 goto out_noclean;
782 }
783 }
784
785 trace_curl_open(file);
786 qemu_co_queue_init(&s->free_state_waitq);
787 s->aio_context = bdrv_get_aio_context(bs);
788 s->url = g_strdup(file);
789 s->sockets = g_hash_table_new_full(NULL, NULL, NULL, g_free);
790 qemu_mutex_lock(&s->mutex);
791 state = curl_find_state(s);
792 qemu_mutex_unlock(&s->mutex);
793 if (!state) {
794 goto out_noclean;
795 }
796
797 // Get file size
798
799 if (curl_init_state(s, state) < 0) {
800 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
801 "curl library initialization failed.");
802 goto out;
803 }
804
805 s->accept_range = false;
806 if (curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1) ||
807 curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION, curl_header_cb) ||
808 curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s)) {
809 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
810 "curl library initialization failed.");
811 goto out;
812 }
813 if (curl_easy_perform(state->curl))
814 goto out;
815 /* CURL 7.55.0 deprecates CURLINFO_CONTENT_LENGTH_DOWNLOAD in favour of
816 * the *_T version which returns a more sensible type for content length.
817 */
818 #if LIBCURL_VERSION_NUM >= 0x073700
819 if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD_T, &cl)) {
820 goto out;
821 }
822 #else
823 if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &cl)) {
824 goto out;
825 }
826 #endif
827 /* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
828 * know or the size is zero. From 7.19.4 CURL returns -1 if size is not
829 * known and zero if it is really zero-length file. */
830 #if LIBCURL_VERSION_NUM >= 0x071304
831 if (cl < 0) {
832 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
833 "Server didn't report file size.");
834 goto out;
835 }
836 #else
837 if (cl <= 0) {
838 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
839 "Unknown file size or zero-length file.");
840 goto out;
841 }
842 #endif
843
844 s->len = cl;
845
846 if ((!strncasecmp(s->url, "http://", strlen("http://"))
847 || !strncasecmp(s->url, "https://", strlen("https://")))
848 && !s->accept_range) {
849 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
850 "Server does not support 'range' (byte ranges).");
851 goto out;
852 }
853 trace_curl_open_size(s->len);
854
855 qemu_mutex_lock(&s->mutex);
856 curl_clean_state(state);
857 qemu_mutex_unlock(&s->mutex);
858 curl_easy_cleanup(state->curl);
859 state->curl = NULL;
860
861 curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
862
863 qemu_opts_del(opts);
864 return 0;
865
866 out:
867 error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
868 curl_easy_cleanup(state->curl);
869 state->curl = NULL;
870 out_noclean:
871 qemu_mutex_destroy(&s->mutex);
872 g_free(s->cookie);
873 g_free(s->url);
874 g_free(s->username);
875 g_free(s->proxyusername);
876 g_free(s->proxypassword);
877 if (s->sockets) {
878 curl_drop_all_sockets(s->sockets);
879 g_hash_table_destroy(s->sockets);
880 }
881 qemu_opts_del(opts);
882 return -EINVAL;
883 }
884
curl_setup_preadv(BlockDriverState * bs,CURLAIOCB * acb)885 static void coroutine_fn curl_setup_preadv(BlockDriverState *bs, CURLAIOCB *acb)
886 {
887 CURLState *state;
888 int running;
889
890 BDRVCURLState *s = bs->opaque;
891
892 uint64_t start = acb->offset;
893 uint64_t end;
894
895 qemu_mutex_lock(&s->mutex);
896
897 // In case we have the requested data already (e.g. read-ahead),
898 // we can just call the callback and be done.
899 if (curl_find_buf(s, start, acb->bytes, acb)) {
900 goto out;
901 }
902
903 // No cache found, so let's start a new request
904 for (;;) {
905 state = curl_find_state(s);
906 if (state) {
907 break;
908 }
909 qemu_co_queue_wait(&s->free_state_waitq, &s->mutex);
910 }
911
912 if (curl_init_state(s, state) < 0) {
913 curl_clean_state(state);
914 acb->ret = -EIO;
915 goto out;
916 }
917
918 acb->start = 0;
919 acb->end = MIN(acb->bytes, s->len - start);
920
921 state->buf_off = 0;
922 g_free(state->orig_buf);
923 state->buf_start = start;
924 state->buf_len = MIN(acb->end + s->readahead_size, s->len - start);
925 end = start + state->buf_len - 1;
926 state->orig_buf = g_try_malloc(state->buf_len);
927 if (state->buf_len && state->orig_buf == NULL) {
928 curl_clean_state(state);
929 acb->ret = -ENOMEM;
930 goto out;
931 }
932 state->acb[0] = acb;
933
934 snprintf(state->range, 127, "%" PRIu64 "-%" PRIu64, start, end);
935 trace_curl_setup_preadv(acb->bytes, start, state->range);
936 if (curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range) ||
937 curl_multi_add_handle(s->multi, state->curl) != CURLM_OK) {
938 state->acb[0] = NULL;
939 acb->ret = -EIO;
940
941 curl_clean_state(state);
942 goto out;
943 }
944
945 /* Tell curl it needs to kick things off */
946 curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
947
948 out:
949 qemu_mutex_unlock(&s->mutex);
950 }
951
curl_co_preadv(BlockDriverState * bs,int64_t offset,int64_t bytes,QEMUIOVector * qiov,BdrvRequestFlags flags)952 static int coroutine_fn curl_co_preadv(BlockDriverState *bs,
953 int64_t offset, int64_t bytes, QEMUIOVector *qiov,
954 BdrvRequestFlags flags)
955 {
956 CURLAIOCB acb = {
957 .co = qemu_coroutine_self(),
958 .ret = -EINPROGRESS,
959 .qiov = qiov,
960 .offset = offset,
961 .bytes = bytes
962 };
963
964 curl_setup_preadv(bs, &acb);
965 while (acb.ret == -EINPROGRESS) {
966 qemu_coroutine_yield();
967 }
968 return acb.ret;
969 }
970
curl_close(BlockDriverState * bs)971 static void curl_close(BlockDriverState *bs)
972 {
973 BDRVCURLState *s = bs->opaque;
974
975 trace_curl_close();
976 curl_detach_aio_context(bs);
977 qemu_mutex_destroy(&s->mutex);
978
979 g_hash_table_destroy(s->sockets);
980 g_free(s->cookie);
981 g_free(s->url);
982 g_free(s->username);
983 g_free(s->proxyusername);
984 g_free(s->proxypassword);
985 }
986
curl_co_getlength(BlockDriverState * bs)987 static int64_t coroutine_fn curl_co_getlength(BlockDriverState *bs)
988 {
989 BDRVCURLState *s = bs->opaque;
990 return s->len;
991 }
992
curl_refresh_filename(BlockDriverState * bs)993 static void curl_refresh_filename(BlockDriverState *bs)
994 {
995 BDRVCURLState *s = bs->opaque;
996
997 /* "readahead" and "timeout" do not change the guest-visible data,
998 * so ignore them */
999 if (s->sslverify != CURL_BLOCK_OPT_SSLVERIFY_DEFAULT ||
1000 s->cookie || s->username || s->password || s->proxyusername ||
1001 s->proxypassword)
1002 {
1003 return;
1004 }
1005
1006 pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), s->url);
1007 }
1008
1009
1010 static const char *const curl_strong_runtime_opts[] = {
1011 CURL_BLOCK_OPT_URL,
1012 CURL_BLOCK_OPT_SSLVERIFY,
1013 CURL_BLOCK_OPT_COOKIE,
1014 CURL_BLOCK_OPT_COOKIE_SECRET,
1015 CURL_BLOCK_OPT_USERNAME,
1016 CURL_BLOCK_OPT_PASSWORD_SECRET,
1017 CURL_BLOCK_OPT_PROXY_USERNAME,
1018 CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
1019
1020 NULL
1021 };
1022
1023 static BlockDriver bdrv_http = {
1024 .format_name = "http",
1025 .protocol_name = "http",
1026
1027 .instance_size = sizeof(BDRVCURLState),
1028 .bdrv_parse_filename = curl_parse_filename,
1029 .bdrv_open = curl_open,
1030 .bdrv_close = curl_close,
1031 .bdrv_co_getlength = curl_co_getlength,
1032
1033 .bdrv_co_preadv = curl_co_preadv,
1034
1035 .bdrv_detach_aio_context = curl_detach_aio_context,
1036 .bdrv_attach_aio_context = curl_attach_aio_context,
1037
1038 .bdrv_refresh_filename = curl_refresh_filename,
1039 .strong_runtime_opts = curl_strong_runtime_opts,
1040 };
1041
1042 static BlockDriver bdrv_https = {
1043 .format_name = "https",
1044 .protocol_name = "https",
1045
1046 .instance_size = sizeof(BDRVCURLState),
1047 .bdrv_parse_filename = curl_parse_filename,
1048 .bdrv_open = curl_open,
1049 .bdrv_close = curl_close,
1050 .bdrv_co_getlength = curl_co_getlength,
1051
1052 .bdrv_co_preadv = curl_co_preadv,
1053
1054 .bdrv_detach_aio_context = curl_detach_aio_context,
1055 .bdrv_attach_aio_context = curl_attach_aio_context,
1056
1057 .bdrv_refresh_filename = curl_refresh_filename,
1058 .strong_runtime_opts = curl_strong_runtime_opts,
1059 };
1060
1061 static BlockDriver bdrv_ftp = {
1062 .format_name = "ftp",
1063 .protocol_name = "ftp",
1064
1065 .instance_size = sizeof(BDRVCURLState),
1066 .bdrv_parse_filename = curl_parse_filename,
1067 .bdrv_open = curl_open,
1068 .bdrv_close = curl_close,
1069 .bdrv_co_getlength = curl_co_getlength,
1070
1071 .bdrv_co_preadv = curl_co_preadv,
1072
1073 .bdrv_detach_aio_context = curl_detach_aio_context,
1074 .bdrv_attach_aio_context = curl_attach_aio_context,
1075
1076 .bdrv_refresh_filename = curl_refresh_filename,
1077 .strong_runtime_opts = curl_strong_runtime_opts,
1078 };
1079
1080 static BlockDriver bdrv_ftps = {
1081 .format_name = "ftps",
1082 .protocol_name = "ftps",
1083
1084 .instance_size = sizeof(BDRVCURLState),
1085 .bdrv_parse_filename = curl_parse_filename,
1086 .bdrv_open = curl_open,
1087 .bdrv_close = curl_close,
1088 .bdrv_co_getlength = curl_co_getlength,
1089
1090 .bdrv_co_preadv = curl_co_preadv,
1091
1092 .bdrv_detach_aio_context = curl_detach_aio_context,
1093 .bdrv_attach_aio_context = curl_attach_aio_context,
1094
1095 .bdrv_refresh_filename = curl_refresh_filename,
1096 .strong_runtime_opts = curl_strong_runtime_opts,
1097 };
1098
curl_block_init(void)1099 static void curl_block_init(void)
1100 {
1101 bdrv_register(&bdrv_http);
1102 bdrv_register(&bdrv_https);
1103 bdrv_register(&bdrv_ftp);
1104 bdrv_register(&bdrv_ftps);
1105 }
1106
1107 block_init(curl_block_init);
1108