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