block/curl.c

   1 /*
   2  * QEMU Block driver for CURL images
   3  *
   4  * Copyright (c) 2009 Alexander Graf <[email protected]>
   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 DEBUG_CURL_PRINT 1
  40 #else
  41 #define DEBUG_CURL_PRINT 0
  42 #endif
  43 #define DPRINTF(fmt, ...)                                            \
  44     do {                                                             \
  45         if (DEBUG_CURL_PRINT) {                                      \
  46             fprintf(stderr, fmt, ## __VA_ARGS__);                    \
  47         }                                                            \
  48     } while (0)
  49
  50 #if LIBCURL_VERSION_NUM >= 0x071000
  51 /* The multi interface timer callback was introduced in 7.16.0 */
  52 #define NEED_CURL_TIMER_CALLBACK
  53 #define HAVE_SOCKET_ACTION
  54 #endif
  55
  56 #ifndef HAVE_SOCKET_ACTION
  57 /* If curl_multi_socket_action isn't available, define it statically here in
  58  * terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
  59  * less efficient but still safe. */
  60 static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
  61                                             curl_socket_t sockfd,
  62                                             int ev_bitmask,
  63                                             int *running_handles)
  64 {
  65     return curl_multi_socket(multi_handle, sockfd, running_handles);
  66 }
  67 #define curl_multi_socket_action __curl_multi_socket_action
  68 #endif
  69
  70 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
  71                    CURLPROTO_FTP | CURLPROTO_FTPS)
  72
  73 #define CURL_NUM_STATES 8
  74 #define CURL_NUM_ACB    8
  75 #define READ_AHEAD_DEFAULT (256 * 1024)
  76 #define CURL_TIMEOUT_DEFAULT 5
  77 #define CURL_TIMEOUT_MAX 10000
  78
  79 #define FIND_RET_NONE   0
  80 #define FIND_RET_OK     1
  81 #define FIND_RET_WAIT   2
  82
  83 #define CURL_BLOCK_OPT_URL       "url"
  84 #define CURL_BLOCK_OPT_READAHEAD "readahead"
  85 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
  86 #define CURL_BLOCK_OPT_TIMEOUT "timeout"
  87 #define CURL_BLOCK_OPT_COOKIE    "cookie"
  88 #define CURL_BLOCK_OPT_USERNAME "username"
  89 #define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
  90 #define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
  91 #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
  92
  93 struct BDRVCURLState;
  94
  95 typedef struct CURLAIOCB {
  96     BlockAIOCB common;
  97     QEMUIOVector *qiov;
  98
  99     int64_t sector_num;
 100     int nb_sectors;
 101
 102     size_t start;
 103     size_t end;
 104 } CURLAIOCB;
 105
 106 typedef struct CURLState
 107 {
 108     struct BDRVCURLState *s;
 109     CURLAIOCB *acb[CURL_NUM_ACB];
 110     CURL *curl;
 111     curl_socket_t sock_fd;
 112     char *orig_buf;
 113     size_t buf_start;
 114     size_t buf_off;
 115     size_t buf_len;
 116     char range[128];
 117     char errmsg[CURL_ERROR_SIZE];
 118     char in_use;
 119 } CURLState;
 120
 121 typedef struct BDRVCURLState {
 122     CURLM *multi;
 123     QEMUTimer timer;
 124     size_t len;
 125     CURLState states[CURL_NUM_STATES];
 126     char *url;
 127     size_t readahead_size;
 128     bool sslverify;
 129     uint64_t timeout;
 130     char *cookie;
 131     bool accept_range;
 132     AioContext *aio_context;
 133     char *username;
 134     char *password;
 135     char *proxyusername;
 136     char *proxypassword;
 137 } BDRVCURLState;
 138
 139 static void curl_clean_state(CURLState *s);
 140 static void curl_multi_do(void *arg);
 141 static void curl_multi_read(void *arg);
 142
 143 #ifdef NEED_CURL_TIMER_CALLBACK
 144 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
 145 {
 146     BDRVCURLState *s = opaque;
 147
 148     DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
 149     if (timeout_ms == -1) {
 150         timer_del(&s->timer);
 151     } else {
 152         int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
 153         timer_mod(&s->timer,
 154                   qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
 155     }
 156     return 0;
 157 }
 158 #endif
 159
 160 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 161                         void *userp, void *sp)
 162 {
 163     BDRVCURLState *s;
 164     CURLState *state = NULL;
 165     curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
 166     state->sock_fd = fd;
 167     s = state->s;
 168
 169     DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, (int)fd);
 170     switch (action) {
 171         case CURL_POLL_IN:
 172             aio_set_fd_handler(s->aio_context, fd, false,
 173                                curl_multi_read, NULL, state);
 174             break;
 175         case CURL_POLL_OUT:
 176             aio_set_fd_handler(s->aio_context, fd, false,
 177                                NULL, curl_multi_do, state);
 178             break;
 179         case CURL_POLL_INOUT:
 180             aio_set_fd_handler(s->aio_context, fd, false,
 181                                curl_multi_read, curl_multi_do, state);
 182             break;
 183         case CURL_POLL_REMOVE:
 184             aio_set_fd_handler(s->aio_context, fd, false,
 185                                NULL, NULL, NULL);
 186             break;
 187     }
 188
 189     return 0;
 190 }
 191
 192 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 193 {
 194     BDRVCURLState *s = opaque;
 195     size_t realsize = size * nmemb;
 196     const char *accept_line = "Accept-Ranges: bytes";
 197
 198     if (realsize >= strlen(accept_line)
 199         && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
 200         s->accept_range = true;
 201     }
 202
 203     return realsize;
 204 }
 205
 206 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 207 {
 208     CURLState *s = ((CURLState*)opaque);
 209     size_t realsize = size * nmemb;
 210     int i;
 211
 212     DPRINTF("CURL: Just reading %zd bytes\n", realsize);
 213
 214     if (!s || !s->orig_buf)
 215         return 0;
 216
 217     if (s->buf_off >= s->buf_len) {
 218         /* buffer full, read nothing */
 219         return 0;
 220     }
 221     realsize = MIN(realsize, s->buf_len - s->buf_off);
 222     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
 223     s->buf_off += realsize;
 224
 225     for(i=0; i<CURL_NUM_ACB; i++) {
 226         CURLAIOCB *acb = s->acb[i];
 227
 228         if (!acb)
 229             continue;
 230
 231         if ((s->buf_off >= acb->end)) {
 232             qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
 233                                 acb->end - acb->start);
 234             acb->common.cb(acb->common.opaque, 0);
 235             qemu_aio_unref(acb);
 236             s->acb[i] = NULL;
 237         }
 238     }
 239
 240     return realsize;
 241 }
 242
 243 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
 244                          CURLAIOCB *acb)
 245 {
 246     int i;
 247     size_t end = start + len;
 248
 249     for (i=0; i<CURL_NUM_STATES; i++) {
 250         CURLState *state = &s->states[i];
 251         size_t buf_end = (state->buf_start + state->buf_off);
 252         size_t buf_fend = (state->buf_start + state->buf_len);
 253
 254         if (!state->orig_buf)
 255             continue;
 256         if (!state->buf_off)
 257             continue;
 258
 259         // Does the existing buffer cover our section?
 260         if ((start >= state->buf_start) &&
 261             (start <= buf_end) &&
 262             (end >= state->buf_start) &&
 263             (end <= buf_end))
 264         {
 265             char *buf = state->orig_buf + (start - state->buf_start);
 266
 267             qemu_iovec_from_buf(acb->qiov, 0, buf, len);
 268             acb->common.cb(acb->common.opaque, 0);
 269
 270             return FIND_RET_OK;
 271         }
 272
 273         // Wait for unfinished chunks
 274         if (state->in_use &&
 275             (start >= state->buf_start) &&
 276             (start <= buf_fend) &&
 277             (end >= state->buf_start) &&
 278             (end <= buf_fend))
 279         {
 280             int j;
 281
 282             acb->start = start - state->buf_start;
 283             acb->end = acb->start + len;
 284
 285             for (j=0; j<CURL_NUM_ACB; j++) {
 286                 if (!state->acb[j]) {
 287                     state->acb[j] = acb;
 288                     return FIND_RET_WAIT;
 289                 }
 290             }
 291         }
 292     }
 293
 294     return FIND_RET_NONE;
 295 }
 296
 297 static void curl_multi_check_completion(BDRVCURLState *s)
 298 {
 299     int msgs_in_queue;
 300
 301     /* Try to find done transfers, so we can free the easy
 302      * handle again. */
 303     for (;;) {
 304         CURLMsg *msg;
 305         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 306
 307         /* Quit when there are no more completions */
 308         if (!msg)
 309             break;
 310
 311         if (msg->msg == CURLMSG_DONE) {
 312             CURLState *state = NULL;
 313             curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
 314                               (char **)&state);
 315
 316             /* ACBs for successful messages get completed in curl_read_cb */
 317             if (msg->data.result != CURLE_OK) {
 318                 int i;
 319                 static int errcount = 100;
 320
 321                 /* Don't lose the original error message from curl, since
 322                  * it contains extra data.
 323                  */
 324                 if (errcount > 0) {
 325                     error_report("curl: %s", state->errmsg);
 326                     if (--errcount == 0) {
 327                         error_report("curl: further errors suppressed");
 328                     }
 329                 }
 330
 331                 for (i = 0; i < CURL_NUM_ACB; i++) {
 332                     CURLAIOCB *acb = state->acb[i];
 333
 334                     if (acb == NULL) {
 335                         continue;
 336                     }
 337
 338                     acb->common.cb(acb->common.opaque, -EPROTO);
 339                     qemu_aio_unref(acb);
 340                     state->acb[i] = NULL;
 341                 }
 342             }
 343
 344             curl_clean_state(state);
 345             break;
 346         }
 347     }
 348 }
 349
 350 static void curl_multi_do(void *arg)
 351 {
 352     CURLState *s = (CURLState *)arg;
 353     int running;
 354     int r;
 355
 356     if (!s->s->multi) {
 357         return;
 358     }
 359
 360     do {
 361         r = curl_multi_socket_action(s->s->multi, s->sock_fd, 0, &running);
 362     } while(r == CURLM_CALL_MULTI_PERFORM);
 363
 364 }
 365
 366 static void curl_multi_read(void *arg)
 367 {
 368     CURLState *s = (CURLState *)arg;
 369
 370     curl_multi_do(arg);
 371     curl_multi_check_completion(s->s);
 372 }
 373
 374 static void curl_multi_timeout_do(void *arg)
 375 {
 376 #ifdef NEED_CURL_TIMER_CALLBACK
 377     BDRVCURLState *s = (BDRVCURLState *)arg;
 378     int running;
 379
 380     if (!s->multi) {
 381         return;
 382     }
 383
 384     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 385
 386     curl_multi_check_completion(s);
 387 #else
 388     abort();
 389 #endif
 390 }
 391
 392 static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
 393 {
 394     CURLState *state = NULL;
 395     int i, j;
 396
 397     do {
 398         for (i=0; i<CURL_NUM_STATES; i++) {
 399             for (j=0; j<CURL_NUM_ACB; j++)
 400                 if (s->states[i].acb[j])
 401                     continue;
 402             if (s->states[i].in_use)
 403                 continue;
 404
 405             state = &s->states[i];
 406             state->in_use = 1;
 407             break;
 408         }
 409         if (!state) {
 410             aio_poll(bdrv_get_aio_context(bs), true);
 411         }
 412     } while(!state);
 413
 414     if (!state->curl) {
 415         state->curl = curl_easy_init();
 416         if (!state->curl) {
 417             return NULL;
 418         }
 419         curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
 420         curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
 421                          (long) s->sslverify);
 422         if (s->cookie) {
 423             curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
 424         }
 425         curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
 426         curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
 427                          (void *)curl_read_cb);
 428         curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
 429         curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
 430         curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
 431         curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
 432         curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
 433         curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
 434         curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 435
 436         if (s->username) {
 437             curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
 438         }
 439         if (s->password) {
 440             curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
 441         }
 442         if (s->proxyusername) {
 443             curl_easy_setopt(state->curl,
 444                              CURLOPT_PROXYUSERNAME, s->proxyusername);
 445         }
 446         if (s->proxypassword) {
 447             curl_easy_setopt(state->curl,
 448                              CURLOPT_PROXYPASSWORD, s->proxypassword);
 449         }
 450
 451         /* Restrict supported protocols to avoid security issues in the more
 452          * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
 453          * CVE-2013-0249.
 454          *
 455          * Restricting protocols is only supported from 7.19.4 upwards.
 456          */
 457 #if LIBCURL_VERSION_NUM >= 0x071304
 458         curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
 459         curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
 460 #endif
 461
 462 #ifdef DEBUG_VERBOSE
 463         curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
 464 #endif
 465     }
 466
 467     state->s = s;
 468
 469     return state;
 470 }
 471
 472 static void curl_clean_state(CURLState *s)
 473 {
 474     if (s->s->multi)
 475         curl_multi_remove_handle(s->s->multi, s->curl);
 476     s->in_use = 0;
 477 }
 478
 479 static void curl_parse_filename(const char *filename, QDict *options,
 480                                 Error **errp)
 481 {
 482     qdict_put(options, CURL_BLOCK_OPT_URL, qstring_from_str(filename));
 483 }
 484
 485 static void curl_detach_aio_context(BlockDriverState *bs)
 486 {
 487     BDRVCURLState *s = bs->opaque;
 488     int i;
 489
 490     for (i = 0; i < CURL_NUM_STATES; i++) {
 491         if (s->states[i].in_use) {
 492             curl_clean_state(&s->states[i]);
 493         }
 494         if (s->states[i].curl) {
 495             curl_easy_cleanup(s->states[i].curl);
 496             s->states[i].curl = NULL;
 497         }
 498         g_free(s->states[i].orig_buf);
 499         s->states[i].orig_buf = NULL;
 500     }
 501     if (s->multi) {
 502         curl_multi_cleanup(s->multi);
 503         s->multi = NULL;
 504     }
 505
 506     timer_del(&s->timer);
 507 }
 508
 509 static void curl_attach_aio_context(BlockDriverState *bs,
 510                                     AioContext *new_context)
 511 {
 512     BDRVCURLState *s = bs->opaque;
 513
 514     aio_timer_init(new_context, &s->timer,
 515                    QEMU_CLOCK_REALTIME, SCALE_NS,
 516                    curl_multi_timeout_do, s);
 517
 518     assert(!s->multi);
 519     s->multi = curl_multi_init();
 520     s->aio_context = new_context;
 521     curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
 522 #ifdef NEED_CURL_TIMER_CALLBACK
 523     curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
 524     curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
 525 #endif
 526 }
 527
 528 static QemuOptsList runtime_opts = {
 529     .name = "curl",
 530     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 531     .desc = {
 532         {
 533             .name = CURL_BLOCK_OPT_URL,
 534             .type = QEMU_OPT_STRING,
 535             .help = "URL to open",
 536         },
 537         {
 538             .name = CURL_BLOCK_OPT_READAHEAD,
 539             .type = QEMU_OPT_SIZE,
 540             .help = "Readahead size",
 541         },
 542         {
 543             .name = CURL_BLOCK_OPT_SSLVERIFY,
 544             .type = QEMU_OPT_BOOL,
 545             .help = "Verify SSL certificate"
 546         },
 547         {
 548             .name = CURL_BLOCK_OPT_TIMEOUT,
 549             .type = QEMU_OPT_NUMBER,
 550             .help = "Curl timeout"
 551         },
 552         {
 553             .name = CURL_BLOCK_OPT_COOKIE,
 554             .type = QEMU_OPT_STRING,
 555             .help = "Pass the cookie or list of cookies with each request"
 556         },
 557         {
 558             .name = CURL_BLOCK_OPT_USERNAME,
 559             .type = QEMU_OPT_STRING,
 560             .help = "Username for HTTP auth"
 561         },
 562         {
 563             .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
 564             .type = QEMU_OPT_STRING,
 565             .help = "ID of secret used as password for HTTP auth",
 566         },
 567         {
 568             .name = CURL_BLOCK_OPT_PROXY_USERNAME,
 569             .type = QEMU_OPT_STRING,
 570             .help = "Username for HTTP proxy auth"
 571         },
 572         {
 573             .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
 574             .type = QEMU_OPT_STRING,
 575             .help = "ID of secret used as password for HTTP proxy auth",
 576         },
 577         { /* end of list */ }
 578     },
 579 };
 580
 581
 582 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 583                      Error **errp)
 584 {
 585     BDRVCURLState *s = bs->opaque;
 586     CURLState *state = NULL;
 587     QemuOpts *opts;
 588     Error *local_err = NULL;
 589     const char *file;
 590     const char *cookie;
 591     double d;
 592     const char *secretid;
 593
 594     static int inited = 0;
 595
 596     if (flags & BDRV_O_RDWR) {
 597         error_setg(errp, "curl block device does not support writes");
 598         return -EROFS;
 599     }
 600
 601     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 602     qemu_opts_absorb_qdict(opts, options, &local_err);
 603     if (local_err) {
 604         error_propagate(errp, local_err);
 605         goto out_noclean;
 606     }
 607
 608     s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
 609                                           READ_AHEAD_DEFAULT);
 610     if ((s->readahead_size & 0x1ff) != 0) {
 611         error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
 612                    s->readahead_size);
 613         goto out_noclean;
 614     }
 615
 616     s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
 617                                      CURL_TIMEOUT_DEFAULT);
 618     if (s->timeout > CURL_TIMEOUT_MAX) {
 619         error_setg(errp, "timeout parameter is too large or negative");
 620         goto out_noclean;
 621     }
 622
 623     s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
 624
 625     cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
 626     s->cookie = g_strdup(cookie);
 627
 628     file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
 629     if (file == NULL) {
 630         error_setg(errp, "curl block driver requires an 'url' option");
 631         goto out_noclean;
 632     }
 633
 634     s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
 635     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
 636
 637     if (secretid) {
 638         s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
 639         if (!s->password) {
 640             goto out_noclean;
 641         }
 642     }
 643
 644     s->proxyusername = g_strdup(
 645         qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
 646     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
 647     if (secretid) {
 648         s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
 649         if (!s->proxypassword) {
 650             goto out_noclean;
 651         }
 652     }
 653
 654     if (!inited) {
 655         curl_global_init(CURL_GLOBAL_ALL);
 656         inited = 1;
 657     }
 658
 659     DPRINTF("CURL: Opening %s\n", file);
 660     s->aio_context = bdrv_get_aio_context(bs);
 661     s->url = g_strdup(file);
 662     state = curl_init_state(bs, s);
 663     if (!state)
 664         goto out_noclean;
 665
 666     // Get file size
 667
 668     s->accept_range = false;
 669     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
 670     curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
 671                      curl_header_cb);
 672     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
 673     if (curl_easy_perform(state->curl))
 674         goto out;
 675     if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
 676         goto out;
 677     }
 678     /* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
 679      * know or the size is zero. From 7.19.4 CURL returns -1 if size is not
 680      * known and zero if it is realy zero-length file. */
 681 #if LIBCURL_VERSION_NUM >= 0x071304
 682     if (d < 0) {
 683         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 684                 "Server didn't report file size.");
 685         goto out;
 686     }
 687 #else
 688     if (d <= 0) {
 689         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 690                 "Unknown file size or zero-length file.");
 691         goto out;
 692     }
 693 #endif
 694
 695     s->len = (size_t)d;
 696
 697     if ((!strncasecmp(s->url, "http://", strlen("http://"))
 698         || !strncasecmp(s->url, "https://", strlen("https://")))
 699         && !s->accept_range) {
 700         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 701                 "Server does not support 'range' (byte ranges).");
 702         goto out;
 703     }
 704     DPRINTF("CURL: Size = %zd\n", s->len);
 705
 706     curl_clean_state(state);
 707     curl_easy_cleanup(state->curl);
 708     state->curl = NULL;
 709
 710     curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
 711
 712     qemu_opts_del(opts);
 713     return 0;
 714
 715 out:
 716     error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
 717     curl_easy_cleanup(state->curl);
 718     state->curl = NULL;
 719 out_noclean:
 720     g_free(s->cookie);
 721     g_free(s->url);
 722     qemu_opts_del(opts);
 723     return -EINVAL;
 724 }
 725
 726 static const AIOCBInfo curl_aiocb_info = {
 727     .aiocb_size         = sizeof(CURLAIOCB),
 728 };
 729
 730
 731 static void curl_readv_bh_cb(void *p)
 732 {
 733     CURLState *state;
 734     int running;
 735
 736     CURLAIOCB *acb = p;
 737     BDRVCURLState *s = acb->common.bs->opaque;
 738
 739     size_t start = acb->sector_num * BDRV_SECTOR_SIZE;
 740     size_t end;
 741
 742     // In case we have the requested data already (e.g. read-ahead),
 743     // we can just call the callback and be done.
 744     switch (curl_find_buf(s, start, acb->nb_sectors * BDRV_SECTOR_SIZE, acb)) {
 745         case FIND_RET_OK:
 746             qemu_aio_unref(acb);
 747             // fall through
 748         case FIND_RET_WAIT:
 749             return;
 750         default:
 751             break;
 752     }
 753
 754     // No cache found, so let's start a new request
 755     state = curl_init_state(acb->common.bs, s);
 756     if (!state) {
 757         acb->common.cb(acb->common.opaque, -EIO);
 758         qemu_aio_unref(acb);
 759         return;
 760     }
 761
 762     acb->start = 0;
 763     acb->end = (acb->nb_sectors * BDRV_SECTOR_SIZE);
 764
 765     state->buf_off = 0;
 766     g_free(state->orig_buf);
 767     state->buf_start = start;
 768     state->buf_len = acb->end + s->readahead_size;
 769     end = MIN(start + state->buf_len, s->len) - 1;
 770     state->orig_buf = g_try_malloc(state->buf_len);
 771     if (state->buf_len && state->orig_buf == NULL) {
 772         curl_clean_state(state);
 773         acb->common.cb(acb->common.opaque, -ENOMEM);
 774         qemu_aio_unref(acb);
 775         return;
 776     }
 777     state->acb[0] = acb;
 778
 779     snprintf(state->range, 127, "%zd-%zd", start, end);
 780     DPRINTF("CURL (AIO): Reading %llu at %zd (%s)\n",
 781             (acb->nb_sectors * BDRV_SECTOR_SIZE), start, state->range);
 782     curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
 783
 784     curl_multi_add_handle(s->multi, state->curl);
 785
 786     /* Tell curl it needs to kick things off */
 787     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 788 }
 789
 790 static BlockAIOCB *curl_aio_readv(BlockDriverState *bs,
 791         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 792         BlockCompletionFunc *cb, void *opaque)
 793 {
 794     CURLAIOCB *acb;
 795
 796     acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
 797
 798     acb->qiov = qiov;
 799     acb->sector_num = sector_num;
 800     acb->nb_sectors = nb_sectors;
 801
 802     aio_bh_schedule_oneshot(bdrv_get_aio_context(bs), curl_readv_bh_cb, acb);
 803     return &acb->common;
 804 }
 805
 806 static void curl_close(BlockDriverState *bs)
 807 {
 808     BDRVCURLState *s = bs->opaque;
 809
 810     DPRINTF("CURL: Close\n");
 811     curl_detach_aio_context(bs);
 812
 813     g_free(s->cookie);
 814     g_free(s->url);
 815 }
 816
 817 static int64_t curl_getlength(BlockDriverState *bs)
 818 {
 819     BDRVCURLState *s = bs->opaque;
 820     return s->len;
 821 }
 822
 823 static BlockDriver bdrv_http = {
 824     .format_name                = "http",
 825     .protocol_name              = "http",
 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_https = {
 840     .format_name                = "https",
 841     .protocol_name              = "https",
 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_ftp = {
 856     .format_name                = "ftp",
 857     .protocol_name              = "ftp",
 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_ftps = {
 872     .format_name                = "ftps",
 873     .protocol_name              = "ftps",
 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 }
 894
 895 block_init(curl_block_init);