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/osdep.h"
  25 #include "qapi/error.h"
  26 #include "qemu-common.h"
  27 #include "qemu/error-report.h"
  28 #include "block/block_int.h"
  29 #include "qapi/qmp/qbool.h"
  30 #include "qapi/qmp/qstring.h"
  31 #include "crypto/secret.h"
  32 #include <curl/curl.h>
  33 #include "qemu/cutils.h"
  34
  35 // #define DEBUG_CURL
  36 // #define DEBUG_VERBOSE
  37
  38 #ifdef DEBUG_CURL
  39 #define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0)
  40 #else
  41 #define DPRINTF(fmt, ...) do { } while (0)
  42 #endif
  43
  44 #if LIBCURL_VERSION_NUM >= 0x071000
  45 /* The multi interface timer callback was introduced in 7.16.0 */
  46 #define NEED_CURL_TIMER_CALLBACK
  47 #define HAVE_SOCKET_ACTION
  48 #endif
  49
  50 #ifndef HAVE_SOCKET_ACTION
  51 /* If curl_multi_socket_action isn't available, define it statically here in
  52  * terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
  53  * less efficient but still safe. */
  54 static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
  55                                             curl_socket_t sockfd,
  56                                             int ev_bitmask,
  57                                             int *running_handles)
  58 {
  59     return curl_multi_socket(multi_handle, sockfd, running_handles);
  60 }
  61 #define curl_multi_socket_action __curl_multi_socket_action
  62 #endif
  63
  64 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
  65                    CURLPROTO_FTP | CURLPROTO_FTPS | \
  66                    CURLPROTO_TFTP)
  67
  68 #define CURL_NUM_STATES 8
  69 #define CURL_NUM_ACB    8
  70 #define SECTOR_SIZE     512
  71 #define READ_AHEAD_DEFAULT (256 * 1024)
  72 #define CURL_TIMEOUT_DEFAULT 5
  73 #define CURL_TIMEOUT_MAX 10000
  74
  75 #define FIND_RET_NONE   0
  76 #define FIND_RET_OK     1
  77 #define FIND_RET_WAIT   2
  78
  79 #define CURL_BLOCK_OPT_URL       "url"
  80 #define CURL_BLOCK_OPT_READAHEAD "readahead"
  81 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
  82 #define CURL_BLOCK_OPT_TIMEOUT "timeout"
  83 #define CURL_BLOCK_OPT_COOKIE    "cookie"
  84 #define CURL_BLOCK_OPT_USERNAME "username"
  85 #define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
  86 #define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
  87 #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
  88
  89 struct BDRVCURLState;
  90
  91 typedef struct CURLAIOCB {
  92     BlockAIOCB common;
  93     QEMUBH *bh;
  94     QEMUIOVector *qiov;
  95
  96     int64_t sector_num;
  97     int nb_sectors;
  98
  99     size_t start;
 100     size_t end;
 101 } CURLAIOCB;
 102
 103 typedef struct CURLState
 104 {
 105     struct BDRVCURLState *s;
 106     CURLAIOCB *acb[CURL_NUM_ACB];
 107     CURL *curl;
 108     curl_socket_t sock_fd;
 109     char *orig_buf;
 110     size_t buf_start;
 111     size_t buf_off;
 112     size_t buf_len;
 113     char range[128];
 114     char errmsg[CURL_ERROR_SIZE];
 115     char in_use;
 116 } CURLState;
 117
 118 typedef struct BDRVCURLState {
 119     CURLM *multi;
 120     QEMUTimer timer;
 121     size_t len;
 122     CURLState states[CURL_NUM_STATES];
 123     char *url;
 124     size_t readahead_size;
 125     bool sslverify;
 126     uint64_t timeout;
 127     char *cookie;
 128     bool accept_range;
 129     AioContext *aio_context;
 130     char *username;
 131     char *password;
 132     char *proxyusername;
 133     char *proxypassword;
 134 } BDRVCURLState;
 135
 136 static void curl_clean_state(CURLState *s);
 137 static void curl_multi_do(void *arg);
 138 static void curl_multi_read(void *arg);
 139
 140 #ifdef NEED_CURL_TIMER_CALLBACK
 141 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
 142 {
 143     BDRVCURLState *s = opaque;
 144
 145     DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
 146     if (timeout_ms == -1) {
 147         timer_del(&s->timer);
 148     } else {
 149         int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
 150         timer_mod(&s->timer,
 151                   qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
 152     }
 153     return 0;
 154 }
 155 #endif
 156
 157 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 158                         void *userp, void *sp)
 159 {
 160     BDRVCURLState *s;
 161     CURLState *state = NULL;
 162     curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
 163     state->sock_fd = fd;
 164     s = state->s;
 165
 166     DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
 167     switch (action) {
 168         case CURL_POLL_IN:
 169             aio_set_fd_handler(s->aio_context, fd, false,
 170                                curl_multi_read, NULL, state);
 171             break;
 172         case CURL_POLL_OUT:
 173             aio_set_fd_handler(s->aio_context, fd, false,
 174                                NULL, curl_multi_do, state);
 175             break;
 176         case CURL_POLL_INOUT:
 177             aio_set_fd_handler(s->aio_context, fd, false,
 178                                curl_multi_read, curl_multi_do, state);
 179             break;
 180         case CURL_POLL_REMOVE:
 181             aio_set_fd_handler(s->aio_context, fd, false,
 182                                NULL, NULL, NULL);
 183             break;
 184     }
 185
 186     return 0;
 187 }
 188
 189 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 190 {
 191     BDRVCURLState *s = opaque;
 192     size_t realsize = size * nmemb;
 193     const char *accept_line = "Accept-Ranges: bytes";
 194
 195     if (realsize >= strlen(accept_line)
 196         && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
 197         s->accept_range = true;
 198     }
 199
 200     return realsize;
 201 }
 202
 203 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 204 {
 205     CURLState *s = ((CURLState*)opaque);
 206     size_t realsize = size * nmemb;
 207     int i;
 208
 209     DPRINTF("CURL: Just reading %zd bytes\n", realsize);
 210
 211     if (!s || !s->orig_buf)
 212         return 0;
 213
 214     if (s->buf_off >= s->buf_len) {
 215         /* buffer full, read nothing */
 216         return 0;
 217     }
 218     realsize = MIN(realsize, s->buf_len - s->buf_off);
 219     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
 220     s->buf_off += realsize;
 221
 222     for(i=0; i<CURL_NUM_ACB; i++) {
 223         CURLAIOCB *acb = s->acb[i];
 224
 225         if (!acb)
 226             continue;
 227
 228         if ((s->buf_off >= acb->end)) {
 229             qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
 230                                 acb->end - acb->start);
 231             acb->common.cb(acb->common.opaque, 0);
 232             qemu_aio_unref(acb);
 233             s->acb[i] = NULL;
 234         }
 235     }
 236
 237     return realsize;
 238 }
 239
 240 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
 241                          CURLAIOCB *acb)
 242 {
 243     int i;
 244     size_t end = start + len;
 245
 246     for (i=0; i<CURL_NUM_STATES; i++) {
 247         CURLState *state = &s->states[i];
 248         size_t buf_end = (state->buf_start + state->buf_off);
 249         size_t buf_fend = (state->buf_start + state->buf_len);
 250
 251         if (!state->orig_buf)
 252             continue;
 253         if (!state->buf_off)
 254             continue;
 255
 256         // Does the existing buffer cover our section?
 257         if ((start >= state->buf_start) &&
 258             (start <= buf_end) &&
 259             (end >= state->buf_start) &&
 260             (end <= buf_end))
 261         {
 262             char *buf = state->orig_buf + (start - state->buf_start);
 263
 264             qemu_iovec_from_buf(acb->qiov, 0, buf, len);
 265             acb->common.cb(acb->common.opaque, 0);
 266
 267             return FIND_RET_OK;
 268         }
 269
 270         // Wait for unfinished chunks
 271         if (state->in_use &&
 272             (start >= state->buf_start) &&
 273             (start <= buf_fend) &&
 274             (end >= state->buf_start) &&
 275             (end <= buf_fend))
 276         {
 277             int j;
 278
 279             acb->start = start - state->buf_start;
 280             acb->end = acb->start + len;
 281
 282             for (j=0; j<CURL_NUM_ACB; j++) {
 283                 if (!state->acb[j]) {
 284                     state->acb[j] = acb;
 285                     return FIND_RET_WAIT;
 286                 }
 287             }
 288         }
 289     }
 290
 291     return FIND_RET_NONE;
 292 }
 293
 294 static void curl_multi_check_completion(BDRVCURLState *s)
 295 {
 296     int msgs_in_queue;
 297
 298     /* Try to find done transfers, so we can free the easy
 299      * handle again. */
 300     for (;;) {
 301         CURLMsg *msg;
 302         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 303
 304         /* Quit when there are no more completions */
 305         if (!msg)
 306             break;
 307
 308         if (msg->msg == CURLMSG_DONE) {
 309             CURLState *state = NULL;
 310             curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
 311                               (char **)&state);
 312
 313             /* ACBs for successful messages get completed in curl_read_cb */
 314             if (msg->data.result != CURLE_OK) {
 315                 int i;
 316                 static int errcount = 100;
 317
 318                 /* Don't lose the original error message from curl, since
 319                  * it contains extra data.
 320                  */
 321                 if (errcount > 0) {
 322                     error_report("curl: %s", state->errmsg);
 323                     if (--errcount == 0) {
 324                         error_report("curl: further errors suppressed");
 325                     }
 326                 }
 327
 328                 for (i = 0; i < CURL_NUM_ACB; i++) {
 329                     CURLAIOCB *acb = state->acb[i];
 330
 331                     if (acb == NULL) {
 332                         continue;
 333                     }
 334
 335                     acb->common.cb(acb->common.opaque, -EPROTO);
 336                     qemu_aio_unref(acb);
 337                     state->acb[i] = NULL;
 338                 }
 339             }
 340
 341             curl_clean_state(state);
 342             break;
 343         }
 344     }
 345 }
 346
 347 static void curl_multi_do(void *arg)
 348 {
 349     CURLState *s = (CURLState *)arg;
 350     int running;
 351     int r;
 352
 353     if (!s->s->multi) {
 354         return;
 355     }
 356
 357     do {
 358         r = curl_multi_socket_action(s->s->multi, s->sock_fd, 0, &running);
 359     } while(r == CURLM_CALL_MULTI_PERFORM);
 360
 361 }
 362
 363 static void curl_multi_read(void *arg)
 364 {
 365     CURLState *s = (CURLState *)arg;
 366
 367     curl_multi_do(arg);
 368     curl_multi_check_completion(s->s);
 369 }
 370
 371 static void curl_multi_timeout_do(void *arg)
 372 {
 373 #ifdef NEED_CURL_TIMER_CALLBACK
 374     BDRVCURLState *s = (BDRVCURLState *)arg;
 375     int running;
 376
 377     if (!s->multi) {
 378         return;
 379     }
 380
 381     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 382
 383     curl_multi_check_completion(s);
 384 #else
 385     abort();
 386 #endif
 387 }
 388
 389 static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
 390 {
 391     CURLState *state = NULL;
 392     int i, j;
 393
 394     do {
 395         for (i=0; i<CURL_NUM_STATES; i++) {
 396             for (j=0; j<CURL_NUM_ACB; j++)
 397                 if (s->states[i].acb[j])
 398                     continue;
 399             if (s->states[i].in_use)
 400                 continue;
 401
 402             state = &s->states[i];
 403             state->in_use = 1;
 404             break;
 405         }
 406         if (!state) {
 407             aio_poll(bdrv_get_aio_context(bs), true);
 408         }
 409     } while(!state);
 410
 411     if (!state->curl) {
 412         state->curl = curl_easy_init();
 413         if (!state->curl) {
 414             return NULL;
 415         }
 416         curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
 417         curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
 418                          (long) s->sslverify);
 419         if (s->cookie) {
 420             curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
 421         }
 422         curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
 423         curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
 424                          (void *)curl_read_cb);
 425         curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
 426         curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
 427         curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
 428         curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
 429         curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
 430         curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
 431         curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 432
 433         if (s->username) {
 434             curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
 435         }
 436         if (s->password) {
 437             curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
 438         }
 439         if (s->proxyusername) {
 440             curl_easy_setopt(state->curl,
 441                              CURLOPT_PROXYUSERNAME, s->proxyusername);
 442         }
 443         if (s->proxypassword) {
 444             curl_easy_setopt(state->curl,
 445                              CURLOPT_PROXYPASSWORD, s->proxypassword);
 446         }
 447
 448         /* Restrict supported protocols to avoid security issues in the more
 449          * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
 450          * CVE-2013-0249.
 451          *
 452          * Restricting protocols is only supported from 7.19.4 upwards.
 453          */
 454 #if LIBCURL_VERSION_NUM >= 0x071304
 455         curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
 456         curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
 457 #endif
 458
 459 #ifdef DEBUG_VERBOSE
 460         curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
 461 #endif
 462     }
 463
 464     state->s = s;
 465
 466     return state;
 467 }
 468
 469 static void curl_clean_state(CURLState *s)
 470 {
 471     if (s->s->multi)
 472         curl_multi_remove_handle(s->s->multi, s->curl);
 473     s->in_use = 0;
 474 }
 475
 476 static void curl_parse_filename(const char *filename, QDict *options,
 477                                 Error **errp)
 478 {
 479     qdict_put(options, CURL_BLOCK_OPT_URL, qstring_from_str(filename));
 480 }
 481
 482 static void curl_detach_aio_context(BlockDriverState *bs)
 483 {
 484     BDRVCURLState *s = bs->opaque;
 485     int i;
 486
 487     for (i = 0; i < CURL_NUM_STATES; i++) {
 488         if (s->states[i].in_use) {
 489             curl_clean_state(&s->states[i]);
 490         }
 491         if (s->states[i].curl) {
 492             curl_easy_cleanup(s->states[i].curl);
 493             s->states[i].curl = NULL;
 494         }
 495         g_free(s->states[i].orig_buf);
 496         s->states[i].orig_buf = NULL;
 497     }
 498     if (s->multi) {
 499         curl_multi_cleanup(s->multi);
 500         s->multi = NULL;
 501     }
 502
 503     timer_del(&s->timer);
 504 }
 505
 506 static void curl_attach_aio_context(BlockDriverState *bs,
 507                                     AioContext *new_context)
 508 {
 509     BDRVCURLState *s = bs->opaque;
 510
 511     aio_timer_init(new_context, &s->timer,
 512                    QEMU_CLOCK_REALTIME, SCALE_NS,
 513                    curl_multi_timeout_do, s);
 514
 515     assert(!s->multi);
 516     s->multi = curl_multi_init();
 517     s->aio_context = new_context;
 518     curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
 519 #ifdef NEED_CURL_TIMER_CALLBACK
 520     curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
 521     curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
 522 #endif
 523 }
 524
 525 static QemuOptsList runtime_opts = {
 526     .name = "curl",
 527     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 528     .desc = {
 529         {
 530             .name = CURL_BLOCK_OPT_URL,
 531             .type = QEMU_OPT_STRING,
 532             .help = "URL to open",
 533         },
 534         {
 535             .name = CURL_BLOCK_OPT_READAHEAD,
 536             .type = QEMU_OPT_SIZE,
 537             .help = "Readahead size",
 538         },
 539         {
 540             .name = CURL_BLOCK_OPT_SSLVERIFY,
 541             .type = QEMU_OPT_BOOL,
 542             .help = "Verify SSL certificate"
 543         },
 544         {
 545             .name = CURL_BLOCK_OPT_TIMEOUT,
 546             .type = QEMU_OPT_NUMBER,
 547             .help = "Curl timeout"
 548         },
 549         {
 550             .name = CURL_BLOCK_OPT_COOKIE,
 551             .type = QEMU_OPT_STRING,
 552             .help = "Pass the cookie or list of cookies with each request"
 553         },
 554         {
 555             .name = CURL_BLOCK_OPT_USERNAME,
 556             .type = QEMU_OPT_STRING,
 557             .help = "Username for HTTP auth"
 558         },
 559         {
 560             .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
 561             .type = QEMU_OPT_STRING,
 562             .help = "ID of secret used as password for HTTP auth",
 563         },
 564         {
 565             .name = CURL_BLOCK_OPT_PROXY_USERNAME,
 566             .type = QEMU_OPT_STRING,
 567             .help = "Username for HTTP proxy auth"
 568         },
 569         {
 570             .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
 571             .type = QEMU_OPT_STRING,
 572             .help = "ID of secret used as password for HTTP proxy auth",
 573         },
 574         { /* end of list */ }
 575     },
 576 };
 577
 578
 579 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 580                      Error **errp)
 581 {
 582     BDRVCURLState *s = bs->opaque;
 583     CURLState *state = NULL;
 584     QemuOpts *opts;
 585     Error *local_err = NULL;
 586     const char *file;
 587     const char *cookie;
 588     double d;
 589     const char *secretid;
 590
 591     static int inited = 0;
 592
 593     if (flags & BDRV_O_RDWR) {
 594         error_setg(errp, "curl block device does not support writes");
 595         return -EROFS;
 596     }
 597
 598     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 599     qemu_opts_absorb_qdict(opts, options, &local_err);
 600     if (local_err) {
 601         error_propagate(errp, local_err);
 602         goto out_noclean;
 603     }
 604
 605     s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
 606                                           READ_AHEAD_DEFAULT);
 607     if ((s->readahead_size & 0x1ff) != 0) {
 608         error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
 609                    s->readahead_size);
 610         goto out_noclean;
 611     }
 612
 613     s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
 614                                      CURL_TIMEOUT_DEFAULT);
 615     if (s->timeout > CURL_TIMEOUT_MAX) {
 616         error_setg(errp, "timeout parameter is too large or negative");
 617         goto out_noclean;
 618     }
 619
 620     s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
 621
 622     cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
 623     s->cookie = g_strdup(cookie);
 624
 625     file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
 626     if (file == NULL) {
 627         error_setg(errp, "curl block driver requires an 'url' option");
 628         goto out_noclean;
 629     }
 630
 631     s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
 632     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
 633
 634     if (secretid) {
 635         s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
 636         if (!s->password) {
 637             goto out_noclean;
 638         }
 639     }
 640
 641     s->proxyusername = g_strdup(
 642         qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
 643     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
 644     if (secretid) {
 645         s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
 646         if (!s->proxypassword) {
 647             goto out_noclean;
 648         }
 649     }
 650
 651     if (!inited) {
 652         curl_global_init(CURL_GLOBAL_ALL);
 653         inited = 1;
 654     }
 655
 656     DPRINTF("CURL: Opening %s\n", file);
 657     s->aio_context = bdrv_get_aio_context(bs);
 658     s->url = g_strdup(file);
 659     state = curl_init_state(bs, s);
 660     if (!state)
 661         goto out_noclean;
 662
 663     // Get file size
 664
 665     s->accept_range = false;
 666     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
 667     curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
 668                      curl_header_cb);
 669     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
 670     if (curl_easy_perform(state->curl))
 671         goto out;
 672     curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
 673     if (d)
 674         s->len = (size_t)d;
 675     else if(!s->len)
 676         goto out;
 677     if ((!strncasecmp(s->url, "http://", strlen("http://"))
 678         || !strncasecmp(s->url, "https://", strlen("https://")))
 679         && !s->accept_range) {
 680         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 681                 "Server does not support 'range' (byte ranges).");
 682         goto out;
 683     }
 684     DPRINTF("CURL: Size = %zd\n", s->len);
 685
 686     curl_clean_state(state);
 687     curl_easy_cleanup(state->curl);
 688     state->curl = NULL;
 689
 690     curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
 691
 692     qemu_opts_del(opts);
 693     return 0;
 694
 695 out:
 696     error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
 697     curl_easy_cleanup(state->curl);
 698     state->curl = NULL;
 699 out_noclean:
 700     g_free(s->cookie);
 701     g_free(s->url);
 702     qemu_opts_del(opts);
 703     return -EINVAL;
 704 }
 705
 706 static const AIOCBInfo curl_aiocb_info = {
 707     .aiocb_size         = sizeof(CURLAIOCB),
 708 };
 709
 710
 711 static void curl_readv_bh_cb(void *p)
 712 {
 713     CURLState *state;
 714     int running;
 715
 716     CURLAIOCB *acb = p;
 717     BDRVCURLState *s = acb->common.bs->opaque;
 718
 719     qemu_bh_delete(acb->bh);
 720     acb->bh = NULL;
 721
 722     size_t start = acb->sector_num * SECTOR_SIZE;
 723     size_t end;
 724
 725     // In case we have the requested data already (e.g. read-ahead),
 726     // we can just call the callback and be done.
 727     switch (curl_find_buf(s, start, acb->nb_sectors * SECTOR_SIZE, acb)) {
 728         case FIND_RET_OK:
 729             qemu_aio_unref(acb);
 730             // fall through
 731         case FIND_RET_WAIT:
 732             return;
 733         default:
 734             break;
 735     }
 736
 737     // No cache found, so let's start a new request
 738     state = curl_init_state(acb->common.bs, s);
 739     if (!state) {
 740         acb->common.cb(acb->common.opaque, -EIO);
 741         qemu_aio_unref(acb);
 742         return;
 743     }
 744
 745     acb->start = 0;
 746     acb->end = (acb->nb_sectors * SECTOR_SIZE);
 747
 748     state->buf_off = 0;
 749     g_free(state->orig_buf);
 750     state->buf_start = start;
 751     state->buf_len = acb->end + s->readahead_size;
 752     end = MIN(start + state->buf_len, s->len) - 1;
 753     state->orig_buf = g_try_malloc(state->buf_len);
 754     if (state->buf_len && state->orig_buf == NULL) {
 755         curl_clean_state(state);
 756         acb->common.cb(acb->common.opaque, -ENOMEM);
 757         qemu_aio_unref(acb);
 758         return;
 759     }
 760     state->acb[0] = acb;
 761
 762     snprintf(state->range, 127, "%zd-%zd", start, end);
 763     DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
 764             (acb->nb_sectors * SECTOR_SIZE), start, state->range);
 765     curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
 766
 767     curl_multi_add_handle(s->multi, state->curl);
 768
 769     /* Tell curl it needs to kick things off */
 770     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 771 }
 772
 773 static BlockAIOCB *curl_aio_readv(BlockDriverState *bs,
 774         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 775         BlockCompletionFunc *cb, void *opaque)
 776 {
 777     CURLAIOCB *acb;
 778
 779     acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
 780
 781     acb->qiov = qiov;
 782     acb->sector_num = sector_num;
 783     acb->nb_sectors = nb_sectors;
 784
 785     acb->bh = aio_bh_new(bdrv_get_aio_context(bs), curl_readv_bh_cb, acb);
 786     qemu_bh_schedule(acb->bh);
 787     return &acb->common;
 788 }
 789
 790 static void curl_close(BlockDriverState *bs)
 791 {
 792     BDRVCURLState *s = bs->opaque;
 793
 794     DPRINTF("CURL: Close\n");
 795     curl_detach_aio_context(bs);
 796
 797     g_free(s->cookie);
 798     g_free(s->url);
 799 }
 800
 801 static int64_t curl_getlength(BlockDriverState *bs)
 802 {
 803     BDRVCURLState *s = bs->opaque;
 804     return s->len;
 805 }
 806
 807 static BlockDriver bdrv_http = {
 808     .format_name                = "http",
 809     .protocol_name              = "http",
 810
 811     .instance_size              = sizeof(BDRVCURLState),
 812     .bdrv_parse_filename        = curl_parse_filename,
 813     .bdrv_file_open             = curl_open,
 814     .bdrv_close                 = curl_close,
 815     .bdrv_getlength             = curl_getlength,
 816
 817     .bdrv_aio_readv             = curl_aio_readv,
 818
 819     .bdrv_detach_aio_context    = curl_detach_aio_context,
 820     .bdrv_attach_aio_context    = curl_attach_aio_context,
 821 };
 822
 823 static BlockDriver bdrv_https = {
 824     .format_name                = "https",
 825     .protocol_name              = "https",
 826
 827     .instance_size              = sizeof(BDRVCURLState),
 828     .bdrv_parse_filename        = curl_parse_filename,
 829     .bdrv_file_open             = curl_open,
 830     .bdrv_close                 = curl_close,
 831     .bdrv_getlength             = curl_getlength,
 832
 833     .bdrv_aio_readv             = curl_aio_readv,
 834
 835     .bdrv_detach_aio_context    = curl_detach_aio_context,
 836     .bdrv_attach_aio_context    = curl_attach_aio_context,
 837 };
 838
 839 static BlockDriver bdrv_ftp = {
 840     .format_name                = "ftp",
 841     .protocol_name              = "ftp",
 842
 843     .instance_size              = sizeof(BDRVCURLState),
 844     .bdrv_parse_filename        = curl_parse_filename,
 845     .bdrv_file_open             = curl_open,
 846     .bdrv_close                 = curl_close,
 847     .bdrv_getlength             = curl_getlength,
 848
 849     .bdrv_aio_readv             = curl_aio_readv,
 850
 851     .bdrv_detach_aio_context    = curl_detach_aio_context,
 852     .bdrv_attach_aio_context    = curl_attach_aio_context,
 853 };
 854
 855 static BlockDriver bdrv_ftps = {
 856     .format_name                = "ftps",
 857     .protocol_name              = "ftps",
 858
 859     .instance_size              = sizeof(BDRVCURLState),
 860     .bdrv_parse_filename        = curl_parse_filename,
 861     .bdrv_file_open             = curl_open,
 862     .bdrv_close                 = curl_close,
 863     .bdrv_getlength             = curl_getlength,
 864
 865     .bdrv_aio_readv             = curl_aio_readv,
 866
 867     .bdrv_detach_aio_context    = curl_detach_aio_context,
 868     .bdrv_attach_aio_context    = curl_attach_aio_context,
 869 };
 870
 871 static BlockDriver bdrv_tftp = {
 872     .format_name                = "tftp",
 873     .protocol_name              = "tftp",
 874
 875     .instance_size              = sizeof(BDRVCURLState),
 876     .bdrv_parse_filename        = curl_parse_filename,
 877     .bdrv_file_open             = curl_open,
 878     .bdrv_close                 = curl_close,
 879     .bdrv_getlength             = curl_getlength,
 880
 881     .bdrv_aio_readv             = curl_aio_readv,
 882
 883     .bdrv_detach_aio_context    = curl_detach_aio_context,
 884     .bdrv_attach_aio_context    = curl_attach_aio_context,
 885 };
 886
 887 static void curl_block_init(void)
 888 {
 889     bdrv_register(&bdrv_http);
 890     bdrv_register(&bdrv_https);
 891     bdrv_register(&bdrv_ftp);
 892     bdrv_register(&bdrv_ftps);
 893     bdrv_register(&bdrv_tftp);
 894 }
 895
 896 block_init(curl_block_init);