xref: /qemu/block/curl.c (revision 9b89cdb2a5064a87b8a7172fa1748d46aa37a9df)
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_int.h"
31  #include "qapi/qmp/qdict.h"
32  #include "qapi/qmp/qstring.h"
33  #include "crypto/secret.h"
34  #include <curl/curl.h>
35  #include "qemu/cutils.h"
36  #include "trace.h"
37  
38  // #define DEBUG_VERBOSE
39  
40  #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
41                     CURLPROTO_FTP | CURLPROTO_FTPS)
42  
43  #define CURL_NUM_STATES 8
44  #define CURL_NUM_ACB    8
45  #define CURL_TIMEOUT_MAX 10000
46  
47  #define CURL_BLOCK_OPT_URL       "url"
48  #define CURL_BLOCK_OPT_READAHEAD "readahead"
49  #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
50  #define CURL_BLOCK_OPT_TIMEOUT "timeout"
51  #define CURL_BLOCK_OPT_COOKIE    "cookie"
52  #define CURL_BLOCK_OPT_COOKIE_SECRET "cookie-secret"
53  #define CURL_BLOCK_OPT_USERNAME "username"
54  #define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
55  #define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
56  #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
57  
58  #define CURL_BLOCK_OPT_READAHEAD_DEFAULT (256 * 1024)
59  #define CURL_BLOCK_OPT_SSLVERIFY_DEFAULT true
60  #define CURL_BLOCK_OPT_TIMEOUT_DEFAULT 5
61  
62  struct BDRVCURLState;
63  struct CURLState;
64  
65  static bool libcurl_initialized;
66  
67  typedef struct CURLAIOCB {
68      Coroutine *co;
69      QEMUIOVector *qiov;
70  
71      uint64_t offset;
72      uint64_t bytes;
73      int ret;
74  
75      size_t start;
76      size_t end;
77  } CURLAIOCB;
78  
79  typedef struct CURLSocket {
80      int fd;
81      struct BDRVCURLState *s;
82  } CURLSocket;
83  
84  typedef struct CURLState
85  {
86      struct BDRVCURLState *s;
87      CURLAIOCB *acb[CURL_NUM_ACB];
88      CURL *curl;
89      char *orig_buf;
90      uint64_t buf_start;
91      size_t buf_off;
92      size_t buf_len;
93      char range[128];
94      char errmsg[CURL_ERROR_SIZE];
95      char in_use;
96  } CURLState;
97  
98  typedef struct BDRVCURLState {
99      CURLM *multi;
100      QEMUTimer timer;
101      uint64_t len;
102      CURLState states[CURL_NUM_STATES];
103      GHashTable *sockets; /* GINT_TO_POINTER(fd) -> socket */
104      char *url;
105      size_t readahead_size;
106      bool sslverify;
107      uint64_t timeout;
108      char *cookie;
109      bool accept_range;
110      AioContext *aio_context;
111      QemuMutex mutex;
112      CoQueue free_state_waitq;
113      char *username;
114      char *password;
115      char *proxyusername;
116      char *proxypassword;
117  } BDRVCURLState;
118  
119  static void curl_clean_state(CURLState *s);
120  static void curl_multi_do(void *arg);
121  
122  static gboolean curl_drop_socket(void *key, void *value, void *opaque)
123  {
124      CURLSocket *socket = value;
125      BDRVCURLState *s = socket->s;
126  
127      aio_set_fd_handler(s->aio_context, socket->fd, false,
128                         NULL, NULL, NULL, NULL);
129      return true;
130  }
131  
132  static void curl_drop_all_sockets(GHashTable *sockets)
133  {
134      g_hash_table_foreach_remove(sockets, curl_drop_socket, NULL);
135  }
136  
137  /* Called from curl_multi_do_locked, with s->mutex held.  */
138  static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
139  {
140      BDRVCURLState *s = opaque;
141  
142      trace_curl_timer_cb(timeout_ms);
143      if (timeout_ms == -1) {
144          timer_del(&s->timer);
145      } else {
146          int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
147          timer_mod(&s->timer,
148                    qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
149      }
150      return 0;
151  }
152  
153  /* Called from curl_multi_do_locked, with s->mutex held.  */
154  static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
155                          void *userp, void *sp)
156  {
157      BDRVCURLState *s;
158      CURLState *state = NULL;
159      CURLSocket *socket;
160  
161      curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
162      s = state->s;
163  
164      socket = g_hash_table_lookup(s->sockets, GINT_TO_POINTER(fd));
165      if (!socket) {
166          socket = g_new0(CURLSocket, 1);
167          socket->fd = fd;
168          socket->s = s;
169          g_hash_table_insert(s->sockets, GINT_TO_POINTER(fd), socket);
170      }
171  
172      trace_curl_sock_cb(action, (int)fd);
173      switch (action) {
174          case CURL_POLL_IN:
175              aio_set_fd_handler(s->aio_context, fd, false,
176                                 curl_multi_do, NULL, NULL, socket);
177              break;
178          case CURL_POLL_OUT:
179              aio_set_fd_handler(s->aio_context, fd, false,
180                                 NULL, curl_multi_do, NULL, socket);
181              break;
182          case CURL_POLL_INOUT:
183              aio_set_fd_handler(s->aio_context, fd, false,
184                                 curl_multi_do, curl_multi_do, NULL, socket);
185              break;
186          case CURL_POLL_REMOVE:
187              aio_set_fd_handler(s->aio_context, fd, false,
188                                 NULL, NULL, NULL, NULL);
189              break;
190      }
191  
192      if (action == CURL_POLL_REMOVE) {
193          g_hash_table_remove(s->sockets, GINT_TO_POINTER(fd));
194      }
195  
196      return 0;
197  }
198  
199  /* Called from curl_multi_do_locked, with s->mutex held.  */
200  static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
201  {
202      BDRVCURLState *s = opaque;
203      size_t realsize = size * nmemb;
204      const char *header = (char *)ptr;
205      const char *end = header + realsize;
206      const char *accept_ranges = "accept-ranges:";
207      const char *bytes = "bytes";
208  
209      if (realsize >= strlen(accept_ranges)
210          && g_ascii_strncasecmp(header, accept_ranges,
211                                 strlen(accept_ranges)) == 0) {
212  
213          char *p = strchr(header, ':') + 1;
214  
215          /* Skip whitespace between the header name and value. */
216          while (p < end && *p && g_ascii_isspace(*p)) {
217              p++;
218          }
219  
220          if (end - p >= strlen(bytes)
221              && strncmp(p, bytes, strlen(bytes)) == 0) {
222  
223              /* Check that there is nothing but whitespace after the value. */
224              p += strlen(bytes);
225              while (p < end && *p && g_ascii_isspace(*p)) {
226                  p++;
227              }
228  
229              if (p == end || !*p) {
230                  s->accept_range = true;
231              }
232          }
233      }
234  
235      return realsize;
236  }
237  
238  /* Called from curl_multi_do_locked, with s->mutex held.  */
239  static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
240  {
241      CURLState *s = ((CURLState*)opaque);
242      size_t realsize = size * nmemb;
243  
244      trace_curl_read_cb(realsize);
245  
246      if (!s || !s->orig_buf) {
247          goto read_end;
248      }
249  
250      if (s->buf_off >= s->buf_len) {
251          /* buffer full, read nothing */
252          goto read_end;
253      }
254      realsize = MIN(realsize, s->buf_len - s->buf_off);
255      memcpy(s->orig_buf + s->buf_off, ptr, realsize);
256      s->buf_off += realsize;
257  
258  read_end:
259      /* curl will error out if we do not return this value */
260      return size * nmemb;
261  }
262  
263  /* Called with s->mutex held.  */
264  static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
265                            CURLAIOCB *acb)
266  {
267      int i;
268      uint64_t end = start + len;
269      uint64_t clamped_end = MIN(end, s->len);
270      uint64_t clamped_len = clamped_end - start;
271  
272      for (i=0; i<CURL_NUM_STATES; i++) {
273          CURLState *state = &s->states[i];
274          uint64_t buf_end = (state->buf_start + state->buf_off);
275          uint64_t buf_fend = (state->buf_start + state->buf_len);
276  
277          if (!state->orig_buf)
278              continue;
279          if (!state->buf_off)
280              continue;
281  
282          // Does the existing buffer cover our section?
283          if ((start >= state->buf_start) &&
284              (start <= buf_end) &&
285              (clamped_end >= state->buf_start) &&
286              (clamped_end <= buf_end))
287          {
288              char *buf = state->orig_buf + (start - state->buf_start);
289  
290              qemu_iovec_from_buf(acb->qiov, 0, buf, clamped_len);
291              if (clamped_len < len) {
292                  qemu_iovec_memset(acb->qiov, clamped_len, 0, len - clamped_len);
293              }
294              acb->ret = 0;
295              return true;
296          }
297  
298          // Wait for unfinished chunks
299          if (state->in_use &&
300              (start >= state->buf_start) &&
301              (start <= buf_fend) &&
302              (clamped_end >= state->buf_start) &&
303              (clamped_end <= buf_fend))
304          {
305              int j;
306  
307              acb->start = start - state->buf_start;
308              acb->end = acb->start + clamped_len;
309  
310              for (j=0; j<CURL_NUM_ACB; j++) {
311                  if (!state->acb[j]) {
312                      state->acb[j] = acb;
313                      return true;
314                  }
315              }
316          }
317      }
318  
319      return false;
320  }
321  
322  /* Called with s->mutex held.  */
323  static void curl_multi_check_completion(BDRVCURLState *s)
324  {
325      int msgs_in_queue;
326  
327      /* Try to find done transfers, so we can free the easy
328       * handle again. */
329      for (;;) {
330          CURLMsg *msg;
331          msg = curl_multi_info_read(s->multi, &msgs_in_queue);
332  
333          /* Quit when there are no more completions */
334          if (!msg)
335              break;
336  
337          if (msg->msg == CURLMSG_DONE) {
338              int i;
339              CURLState *state = NULL;
340              bool error = msg->data.result != CURLE_OK;
341  
342              curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
343                                (char **)&state);
344  
345              if (error) {
346                  static int errcount = 100;
347  
348                  /* Don't lose the original error message from curl, since
349                   * it contains extra data.
350                   */
351                  if (errcount > 0) {
352                      error_report("curl: %s", state->errmsg);
353                      if (--errcount == 0) {
354                          error_report("curl: further errors suppressed");
355                      }
356                  }
357              }
358  
359              for (i = 0; i < CURL_NUM_ACB; i++) {
360                  CURLAIOCB *acb = state->acb[i];
361  
362                  if (acb == NULL) {
363                      continue;
364                  }
365  
366                  if (!error) {
367                      /* Assert that we have read all data */
368                      assert(state->buf_off >= acb->end);
369  
370                      qemu_iovec_from_buf(acb->qiov, 0,
371                                          state->orig_buf + acb->start,
372                                          acb->end - acb->start);
373  
374                      if (acb->end - acb->start < acb->bytes) {
375                          size_t offset = acb->end - acb->start;
376                          qemu_iovec_memset(acb->qiov, offset, 0,
377                                            acb->bytes - offset);
378                      }
379                  }
380  
381                  acb->ret = error ? -EIO : 0;
382                  state->acb[i] = NULL;
383                  qemu_mutex_unlock(&s->mutex);
384                  aio_co_wake(acb->co);
385                  qemu_mutex_lock(&s->mutex);
386              }
387  
388              curl_clean_state(state);
389              break;
390          }
391      }
392  }
393  
394  /* Called with s->mutex held.  */
395  static void curl_multi_do_locked(CURLSocket *socket)
396  {
397      BDRVCURLState *s = socket->s;
398      int running;
399      int r;
400  
401      if (!s->multi) {
402          return;
403      }
404  
405      do {
406          r = curl_multi_socket_action(s->multi, socket->fd, 0, &running);
407      } while (r == CURLM_CALL_MULTI_PERFORM);
408  }
409  
410  static void curl_multi_do(void *arg)
411  {
412      CURLSocket *socket = arg;
413      BDRVCURLState *s = socket->s;
414  
415      qemu_mutex_lock(&s->mutex);
416      curl_multi_do_locked(socket);
417      curl_multi_check_completion(s);
418      qemu_mutex_unlock(&s->mutex);
419  }
420  
421  static void curl_multi_timeout_do(void *arg)
422  {
423      BDRVCURLState *s = (BDRVCURLState *)arg;
424      int running;
425  
426      if (!s->multi) {
427          return;
428      }
429  
430      qemu_mutex_lock(&s->mutex);
431      curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
432  
433      curl_multi_check_completion(s);
434      qemu_mutex_unlock(&s->mutex);
435  }
436  
437  /* Called with s->mutex held.  */
438  static CURLState *curl_find_state(BDRVCURLState *s)
439  {
440      CURLState *state = NULL;
441      int i;
442  
443      for (i = 0; i < CURL_NUM_STATES; i++) {
444          if (!s->states[i].in_use) {
445              state = &s->states[i];
446              state->in_use = 1;
447              break;
448          }
449      }
450      return state;
451  }
452  
453  static int curl_init_state(BDRVCURLState *s, CURLState *state)
454  {
455      if (!state->curl) {
456          state->curl = curl_easy_init();
457          if (!state->curl) {
458              return -EIO;
459          }
460          curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
461          curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
462                           (long) s->sslverify);
463          curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYHOST,
464                           s->sslverify ? 2L : 0L);
465          if (s->cookie) {
466              curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
467          }
468          curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
469          curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
470                           (void *)curl_read_cb);
471          curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
472          curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
473          curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
474          curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
475          curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
476          curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
477          curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
478  
479          if (s->username) {
480              curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
481          }
482          if (s->password) {
483              curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
484          }
485          if (s->proxyusername) {
486              curl_easy_setopt(state->curl,
487                               CURLOPT_PROXYUSERNAME, s->proxyusername);
488          }
489          if (s->proxypassword) {
490              curl_easy_setopt(state->curl,
491                               CURLOPT_PROXYPASSWORD, s->proxypassword);
492          }
493  
494          /* Restrict supported protocols to avoid security issues in the more
495           * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
496           * CVE-2013-0249.
497           *
498           * Restricting protocols is only supported from 7.19.4 upwards.
499           */
500  #if LIBCURL_VERSION_NUM >= 0x071304
501          curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
502          curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
503  #endif
504  
505  #ifdef DEBUG_VERBOSE
506          curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
507  #endif
508      }
509  
510      state->s = s;
511  
512      return 0;
513  }
514  
515  /* Called with s->mutex held.  */
516  static void curl_clean_state(CURLState *s)
517  {
518      int j;
519      for (j = 0; j < CURL_NUM_ACB; j++) {
520          assert(!s->acb[j]);
521      }
522  
523      if (s->s->multi)
524          curl_multi_remove_handle(s->s->multi, s->curl);
525  
526      s->in_use = 0;
527  
528      qemu_co_enter_next(&s->s->free_state_waitq, &s->s->mutex);
529  }
530  
531  static void curl_parse_filename(const char *filename, QDict *options,
532                                  Error **errp)
533  {
534      qdict_put_str(options, CURL_BLOCK_OPT_URL, filename);
535  }
536  
537  static void curl_detach_aio_context(BlockDriverState *bs)
538  {
539      BDRVCURLState *s = bs->opaque;
540      int i;
541  
542      WITH_QEMU_LOCK_GUARD(&s->mutex) {
543          curl_drop_all_sockets(s->sockets);
544          for (i = 0; i < CURL_NUM_STATES; i++) {
545              if (s->states[i].in_use) {
546                  curl_clean_state(&s->states[i]);
547              }
548              if (s->states[i].curl) {
549                  curl_easy_cleanup(s->states[i].curl);
550                  s->states[i].curl = NULL;
551              }
552              g_free(s->states[i].orig_buf);
553              s->states[i].orig_buf = NULL;
554          }
555          if (s->multi) {
556              curl_multi_cleanup(s->multi);
557              s->multi = NULL;
558          }
559      }
560  
561      timer_del(&s->timer);
562  }
563  
564  static void curl_attach_aio_context(BlockDriverState *bs,
565                                      AioContext *new_context)
566  {
567      BDRVCURLState *s = bs->opaque;
568  
569      aio_timer_init(new_context, &s->timer,
570                     QEMU_CLOCK_REALTIME, SCALE_NS,
571                     curl_multi_timeout_do, s);
572  
573      assert(!s->multi);
574      s->multi = curl_multi_init();
575      s->aio_context = new_context;
576      curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
577      curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
578      curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
579  }
580  
581  static QemuOptsList runtime_opts = {
582      .name = "curl",
583      .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
584      .desc = {
585          {
586              .name = CURL_BLOCK_OPT_URL,
587              .type = QEMU_OPT_STRING,
588              .help = "URL to open",
589          },
590          {
591              .name = CURL_BLOCK_OPT_READAHEAD,
592              .type = QEMU_OPT_SIZE,
593              .help = "Readahead size",
594          },
595          {
596              .name = CURL_BLOCK_OPT_SSLVERIFY,
597              .type = QEMU_OPT_BOOL,
598              .help = "Verify SSL certificate"
599          },
600          {
601              .name = CURL_BLOCK_OPT_TIMEOUT,
602              .type = QEMU_OPT_NUMBER,
603              .help = "Curl timeout"
604          },
605          {
606              .name = CURL_BLOCK_OPT_COOKIE,
607              .type = QEMU_OPT_STRING,
608              .help = "Pass the cookie or list of cookies with each request"
609          },
610          {
611              .name = CURL_BLOCK_OPT_COOKIE_SECRET,
612              .type = QEMU_OPT_STRING,
613              .help = "ID of secret used as cookie passed with each request"
614          },
615          {
616              .name = CURL_BLOCK_OPT_USERNAME,
617              .type = QEMU_OPT_STRING,
618              .help = "Username for HTTP auth"
619          },
620          {
621              .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
622              .type = QEMU_OPT_STRING,
623              .help = "ID of secret used as password for HTTP auth",
624          },
625          {
626              .name = CURL_BLOCK_OPT_PROXY_USERNAME,
627              .type = QEMU_OPT_STRING,
628              .help = "Username for HTTP proxy auth"
629          },
630          {
631              .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
632              .type = QEMU_OPT_STRING,
633              .help = "ID of secret used as password for HTTP proxy auth",
634          },
635          { /* end of list */ }
636      },
637  };
638  
639  
640  static int curl_open(BlockDriverState *bs, QDict *options, int flags,
641                       Error **errp)
642  {
643      BDRVCURLState *s = bs->opaque;
644      CURLState *state = NULL;
645      QemuOpts *opts;
646      const char *file;
647      const char *cookie;
648      const char *cookie_secret;
649      double d;
650      const char *secretid;
651      const char *protocol_delimiter;
652      int ret;
653  
654      ret = bdrv_apply_auto_read_only(bs, "curl driver does not support writes",
655                                      errp);
656      if (ret < 0) {
657          return ret;
658      }
659  
660      if (!libcurl_initialized) {
661          ret = curl_global_init(CURL_GLOBAL_ALL);
662          if (ret) {
663              error_setg(errp, "libcurl initialization failed with %d", ret);
664              return -EIO;
665          }
666          libcurl_initialized = true;
667      }
668  
669      qemu_mutex_init(&s->mutex);
670      opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
671      if (!qemu_opts_absorb_qdict(opts, options, errp)) {
672          goto out_noclean;
673      }
674  
675      s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
676                                            CURL_BLOCK_OPT_READAHEAD_DEFAULT);
677      if ((s->readahead_size & 0x1ff) != 0) {
678          error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
679                     s->readahead_size);
680          goto out_noclean;
681      }
682  
683      s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
684                                       CURL_BLOCK_OPT_TIMEOUT_DEFAULT);
685      if (s->timeout > CURL_TIMEOUT_MAX) {
686          error_setg(errp, "timeout parameter is too large or negative");
687          goto out_noclean;
688      }
689  
690      s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY,
691                                       CURL_BLOCK_OPT_SSLVERIFY_DEFAULT);
692  
693      cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
694      cookie_secret = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE_SECRET);
695  
696      if (cookie && cookie_secret) {
697          error_setg(errp,
698                     "curl driver cannot handle both cookie and cookie secret");
699          goto out_noclean;
700      }
701  
702      if (cookie_secret) {
703          s->cookie = qcrypto_secret_lookup_as_utf8(cookie_secret, errp);
704          if (!s->cookie) {
705              goto out_noclean;
706          }
707      } else {
708          s->cookie = g_strdup(cookie);
709      }
710  
711      file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
712      if (file == NULL) {
713          error_setg(errp, "curl block driver requires an 'url' option");
714          goto out_noclean;
715      }
716  
717      if (!strstart(file, bs->drv->protocol_name, &protocol_delimiter) ||
718          !strstart(protocol_delimiter, "://", NULL))
719      {
720          error_setg(errp, "%s curl driver cannot handle the URL '%s' (does not "
721                     "start with '%s://')", bs->drv->protocol_name, file,
722                     bs->drv->protocol_name);
723          goto out_noclean;
724      }
725  
726      s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
727      secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
728  
729      if (secretid) {
730          s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
731          if (!s->password) {
732              goto out_noclean;
733          }
734      }
735  
736      s->proxyusername = g_strdup(
737          qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
738      secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
739      if (secretid) {
740          s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
741          if (!s->proxypassword) {
742              goto out_noclean;
743          }
744      }
745  
746      trace_curl_open(file);
747      qemu_co_queue_init(&s->free_state_waitq);
748      s->aio_context = bdrv_get_aio_context(bs);
749      s->url = g_strdup(file);
750      s->sockets = g_hash_table_new_full(NULL, NULL, NULL, g_free);
751      qemu_mutex_lock(&s->mutex);
752      state = curl_find_state(s);
753      qemu_mutex_unlock(&s->mutex);
754      if (!state) {
755          goto out_noclean;
756      }
757  
758      // Get file size
759  
760      if (curl_init_state(s, state) < 0) {
761          goto out;
762      }
763  
764      s->accept_range = false;
765      curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
766      curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
767                       curl_header_cb);
768      curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
769      if (curl_easy_perform(state->curl))
770          goto out;
771      if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
772          goto out;
773      }
774      /* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
775       * know or the size is zero. From 7.19.4 CURL returns -1 if size is not
776       * known and zero if it is really zero-length file. */
777  #if LIBCURL_VERSION_NUM >= 0x071304
778      if (d < 0) {
779          pstrcpy(state->errmsg, CURL_ERROR_SIZE,
780                  "Server didn't report file size.");
781          goto out;
782      }
783  #else
784      if (d <= 0) {
785          pstrcpy(state->errmsg, CURL_ERROR_SIZE,
786                  "Unknown file size or zero-length file.");
787          goto out;
788      }
789  #endif
790  
791      s->len = d;
792  
793      if ((!strncasecmp(s->url, "http://", strlen("http://"))
794          || !strncasecmp(s->url, "https://", strlen("https://")))
795          && !s->accept_range) {
796          pstrcpy(state->errmsg, CURL_ERROR_SIZE,
797                  "Server does not support 'range' (byte ranges).");
798          goto out;
799      }
800      trace_curl_open_size(s->len);
801  
802      qemu_mutex_lock(&s->mutex);
803      curl_clean_state(state);
804      qemu_mutex_unlock(&s->mutex);
805      curl_easy_cleanup(state->curl);
806      state->curl = NULL;
807  
808      curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
809  
810      qemu_opts_del(opts);
811      return 0;
812  
813  out:
814      error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
815      curl_easy_cleanup(state->curl);
816      state->curl = NULL;
817  out_noclean:
818      qemu_mutex_destroy(&s->mutex);
819      g_free(s->cookie);
820      g_free(s->url);
821      g_free(s->username);
822      g_free(s->proxyusername);
823      g_free(s->proxypassword);
824      curl_drop_all_sockets(s->sockets);
825      g_hash_table_destroy(s->sockets);
826      qemu_opts_del(opts);
827      return -EINVAL;
828  }
829  
830  static void curl_setup_preadv(BlockDriverState *bs, CURLAIOCB *acb)
831  {
832      CURLState *state;
833      int running;
834  
835      BDRVCURLState *s = bs->opaque;
836  
837      uint64_t start = acb->offset;
838      uint64_t end;
839  
840      qemu_mutex_lock(&s->mutex);
841  
842      // In case we have the requested data already (e.g. read-ahead),
843      // we can just call the callback and be done.
844      if (curl_find_buf(s, start, acb->bytes, acb)) {
845          goto out;
846      }
847  
848      // No cache found, so let's start a new request
849      for (;;) {
850          state = curl_find_state(s);
851          if (state) {
852              break;
853          }
854          qemu_co_queue_wait(&s->free_state_waitq, &s->mutex);
855      }
856  
857      if (curl_init_state(s, state) < 0) {
858          curl_clean_state(state);
859          acb->ret = -EIO;
860          goto out;
861      }
862  
863      acb->start = 0;
864      acb->end = MIN(acb->bytes, s->len - start);
865  
866      state->buf_off = 0;
867      g_free(state->orig_buf);
868      state->buf_start = start;
869      state->buf_len = MIN(acb->end + s->readahead_size, s->len - start);
870      end = start + state->buf_len - 1;
871      state->orig_buf = g_try_malloc(state->buf_len);
872      if (state->buf_len && state->orig_buf == NULL) {
873          curl_clean_state(state);
874          acb->ret = -ENOMEM;
875          goto out;
876      }
877      state->acb[0] = acb;
878  
879      snprintf(state->range, 127, "%" PRIu64 "-%" PRIu64, start, end);
880      trace_curl_setup_preadv(acb->bytes, start, state->range);
881      curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
882  
883      if (curl_multi_add_handle(s->multi, state->curl) != CURLM_OK) {
884          state->acb[0] = NULL;
885          acb->ret = -EIO;
886  
887          curl_clean_state(state);
888          goto out;
889      }
890  
891      /* Tell curl it needs to kick things off */
892      curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
893  
894  out:
895      qemu_mutex_unlock(&s->mutex);
896  }
897  
898  static int coroutine_fn curl_co_preadv(BlockDriverState *bs,
899          int64_t offset, int64_t bytes, QEMUIOVector *qiov,
900          BdrvRequestFlags flags)
901  {
902      CURLAIOCB acb = {
903          .co = qemu_coroutine_self(),
904          .ret = -EINPROGRESS,
905          .qiov = qiov,
906          .offset = offset,
907          .bytes = bytes
908      };
909  
910      curl_setup_preadv(bs, &acb);
911      while (acb.ret == -EINPROGRESS) {
912          qemu_coroutine_yield();
913      }
914      return acb.ret;
915  }
916  
917  static void curl_close(BlockDriverState *bs)
918  {
919      BDRVCURLState *s = bs->opaque;
920  
921      trace_curl_close();
922      curl_detach_aio_context(bs);
923      qemu_mutex_destroy(&s->mutex);
924  
925      g_hash_table_destroy(s->sockets);
926      g_free(s->cookie);
927      g_free(s->url);
928      g_free(s->username);
929      g_free(s->proxyusername);
930      g_free(s->proxypassword);
931  }
932  
933  static int64_t curl_getlength(BlockDriverState *bs)
934  {
935      BDRVCURLState *s = bs->opaque;
936      return s->len;
937  }
938  
939  static void curl_refresh_filename(BlockDriverState *bs)
940  {
941      BDRVCURLState *s = bs->opaque;
942  
943      /* "readahead" and "timeout" do not change the guest-visible data,
944       * so ignore them */
945      if (s->sslverify != CURL_BLOCK_OPT_SSLVERIFY_DEFAULT ||
946          s->cookie || s->username || s->password || s->proxyusername ||
947          s->proxypassword)
948      {
949          return;
950      }
951  
952      pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), s->url);
953  }
954  
955  
956  static const char *const curl_strong_runtime_opts[] = {
957      CURL_BLOCK_OPT_URL,
958      CURL_BLOCK_OPT_SSLVERIFY,
959      CURL_BLOCK_OPT_COOKIE,
960      CURL_BLOCK_OPT_COOKIE_SECRET,
961      CURL_BLOCK_OPT_USERNAME,
962      CURL_BLOCK_OPT_PASSWORD_SECRET,
963      CURL_BLOCK_OPT_PROXY_USERNAME,
964      CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
965  
966      NULL
967  };
968  
969  static BlockDriver bdrv_http = {
970      .format_name                = "http",
971      .protocol_name              = "http",
972  
973      .instance_size              = sizeof(BDRVCURLState),
974      .bdrv_parse_filename        = curl_parse_filename,
975      .bdrv_file_open             = curl_open,
976      .bdrv_close                 = curl_close,
977      .bdrv_getlength             = curl_getlength,
978  
979      .bdrv_co_preadv             = curl_co_preadv,
980  
981      .bdrv_detach_aio_context    = curl_detach_aio_context,
982      .bdrv_attach_aio_context    = curl_attach_aio_context,
983  
984      .bdrv_refresh_filename      = curl_refresh_filename,
985      .strong_runtime_opts        = curl_strong_runtime_opts,
986  };
987  
988  static BlockDriver bdrv_https = {
989      .format_name                = "https",
990      .protocol_name              = "https",
991  
992      .instance_size              = sizeof(BDRVCURLState),
993      .bdrv_parse_filename        = curl_parse_filename,
994      .bdrv_file_open             = curl_open,
995      .bdrv_close                 = curl_close,
996      .bdrv_getlength             = curl_getlength,
997  
998      .bdrv_co_preadv             = curl_co_preadv,
999  
1000      .bdrv_detach_aio_context    = curl_detach_aio_context,
1001      .bdrv_attach_aio_context    = curl_attach_aio_context,
1002  
1003      .bdrv_refresh_filename      = curl_refresh_filename,
1004      .strong_runtime_opts        = curl_strong_runtime_opts,
1005  };
1006  
1007  static BlockDriver bdrv_ftp = {
1008      .format_name                = "ftp",
1009      .protocol_name              = "ftp",
1010  
1011      .instance_size              = sizeof(BDRVCURLState),
1012      .bdrv_parse_filename        = curl_parse_filename,
1013      .bdrv_file_open             = curl_open,
1014      .bdrv_close                 = curl_close,
1015      .bdrv_getlength             = curl_getlength,
1016  
1017      .bdrv_co_preadv             = curl_co_preadv,
1018  
1019      .bdrv_detach_aio_context    = curl_detach_aio_context,
1020      .bdrv_attach_aio_context    = curl_attach_aio_context,
1021  
1022      .bdrv_refresh_filename      = curl_refresh_filename,
1023      .strong_runtime_opts        = curl_strong_runtime_opts,
1024  };
1025  
1026  static BlockDriver bdrv_ftps = {
1027      .format_name                = "ftps",
1028      .protocol_name              = "ftps",
1029  
1030      .instance_size              = sizeof(BDRVCURLState),
1031      .bdrv_parse_filename        = curl_parse_filename,
1032      .bdrv_file_open             = curl_open,
1033      .bdrv_close                 = curl_close,
1034      .bdrv_getlength             = curl_getlength,
1035  
1036      .bdrv_co_preadv             = curl_co_preadv,
1037  
1038      .bdrv_detach_aio_context    = curl_detach_aio_context,
1039      .bdrv_attach_aio_context    = curl_attach_aio_context,
1040  
1041      .bdrv_refresh_filename      = curl_refresh_filename,
1042      .strong_runtime_opts        = curl_strong_runtime_opts,
1043  };
1044  
1045  static void curl_block_init(void)
1046  {
1047      bdrv_register(&bdrv_http);
1048      bdrv_register(&bdrv_https);
1049      bdrv_register(&bdrv_ftp);
1050      bdrv_register(&bdrv_ftps);
1051  }
1052  
1053  block_init(curl_block_init);
1054