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 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 CURLSocket {
 107     int fd;
 108     QLIST_ENTRY(CURLSocket) next;
 109 } CURLSocket;
 110
 111 typedef struct CURLState
 112 {
 113     struct BDRVCURLState *s;
 114     CURLAIOCB *acb[CURL_NUM_ACB];
 115     CURL *curl;
 116     QLIST_HEAD(, CURLSocket) sockets;
 117     char *orig_buf;
 118     size_t buf_start;
 119     size_t buf_off;
 120     size_t buf_len;
 121     char range[128];
 122     char errmsg[CURL_ERROR_SIZE];
 123     char in_use;
 124 } CURLState;
 125
 126 typedef struct BDRVCURLState {
 127     CURLM *multi;
 128     QEMUTimer timer;
 129     size_t len;
 130     CURLState states[CURL_NUM_STATES];
 131     char *url;
 132     size_t readahead_size;
 133     bool sslverify;
 134     uint64_t timeout;
 135     char *cookie;
 136     bool accept_range;
 137     AioContext *aio_context;
 138     char *username;
 139     char *password;
 140     char *proxyusername;
 141     char *proxypassword;
 142 } BDRVCURLState;
 143
 144 static void curl_clean_state(CURLState *s);
 145 static void curl_multi_do(void *arg);
 146 static void curl_multi_read(void *arg);
 147
 148 #ifdef NEED_CURL_TIMER_CALLBACK
 149 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
 150 {
 151     BDRVCURLState *s = opaque;
 152
 153     DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
 154     if (timeout_ms == -1) {
 155         timer_del(&s->timer);
 156     } else {
 157         int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
 158         timer_mod(&s->timer,
 159                   qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
 160     }
 161     return 0;
 162 }
 163 #endif
 164
 165 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 166                         void *userp, void *sp)
 167 {
 168     BDRVCURLState *s;
 169     CURLState *state = NULL;
 170     CURLSocket *socket;
 171
 172     curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
 173     s = state->s;
 174
 175     QLIST_FOREACH(socket, &state->sockets, next) {
 176         if (socket->fd == fd) {
 177             if (action == CURL_POLL_REMOVE) {
 178                 QLIST_REMOVE(socket, next);
 179                 g_free(socket);
 180             }
 181             break;
 182         }
 183     }
 184     if (!socket) {
 185         socket = g_new0(CURLSocket, 1);
 186         socket->fd = fd;
 187         QLIST_INSERT_HEAD(&state->sockets, socket, next);
 188     }
 189     socket = NULL;
 190
 191     DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, (int)fd);
 192     switch (action) {
 193         case CURL_POLL_IN:
 194             aio_set_fd_handler(s->aio_context, fd, false,
 195                                curl_multi_read, NULL, state);
 196             break;
 197         case CURL_POLL_OUT:
 198             aio_set_fd_handler(s->aio_context, fd, false,
 199                                NULL, curl_multi_do, state);
 200             break;
 201         case CURL_POLL_INOUT:
 202             aio_set_fd_handler(s->aio_context, fd, false,
 203                                curl_multi_read, curl_multi_do, state);
 204             break;
 205         case CURL_POLL_REMOVE:
 206             aio_set_fd_handler(s->aio_context, fd, false,
 207                                NULL, NULL, NULL);
 208             break;
 209     }
 210
 211     return 0;
 212 }
 213
 214 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 215 {
 216     BDRVCURLState *s = opaque;
 217     size_t realsize = size * nmemb;
 218     const char *accept_line = "Accept-Ranges: bytes";
 219
 220     if (realsize >= strlen(accept_line)
 221         && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
 222         s->accept_range = true;
 223     }
 224
 225     return realsize;
 226 }
 227
 228 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 229 {
 230     CURLState *s = ((CURLState*)opaque);
 231     size_t realsize = size * nmemb;
 232     int i;
 233
 234     DPRINTF("CURL: Just reading %zd bytes\n", realsize);
 235
 236     if (!s || !s->orig_buf) {
 237         goto read_end;
 238     }
 239
 240     if (s->buf_off >= s->buf_len) {
 241         /* buffer full, read nothing */
 242         goto read_end;
 243     }
 244     realsize = MIN(realsize, s->buf_len - s->buf_off);
 245     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
 246     s->buf_off += realsize;
 247
 248     for(i=0; i<CURL_NUM_ACB; i++) {
 249         CURLAIOCB *acb = s->acb[i];
 250
 251         if (!acb)
 252             continue;
 253
 254         if ((s->buf_off >= acb->end)) {
 255             qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
 256                                 acb->end - acb->start);
 257             acb->common.cb(acb->common.opaque, 0);
 258             qemu_aio_unref(acb);
 259             s->acb[i] = NULL;
 260         }
 261     }
 262
 263 read_end:
 264     /* curl will error out if we do not return this value */
 265     return size * nmemb;
 266 }
 267
 268 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
 269                          CURLAIOCB *acb)
 270 {
 271     int i;
 272     size_t end = start + len;
 273
 274     for (i=0; i<CURL_NUM_STATES; i++) {
 275         CURLState *state = &s->states[i];
 276         size_t buf_end = (state->buf_start + state->buf_off);
 277         size_t buf_fend = (state->buf_start + state->buf_len);
 278
 279         if (!state->orig_buf)
 280             continue;
 281         if (!state->buf_off)
 282             continue;
 283
 284         // Does the existing buffer cover our section?
 285         if ((start >= state->buf_start) &&
 286             (start <= buf_end) &&
 287             (end >= state->buf_start) &&
 288             (end <= buf_end))
 289         {
 290             char *buf = state->orig_buf + (start - state->buf_start);
 291
 292             qemu_iovec_from_buf(acb->qiov, 0, buf, len);
 293             acb->common.cb(acb->common.opaque, 0);
 294
 295             return FIND_RET_OK;
 296         }
 297
 298         // Wait for unfinished chunks
 299         if (state->in_use &&
 300             (start >= state->buf_start) &&
 301             (start <= buf_fend) &&
 302             (end >= state->buf_start) &&
 303             (end <= buf_fend))
 304         {
 305             int j;
 306
 307             acb->start = start - state->buf_start;
 308             acb->end = acb->start + len;
 309
 310             for (j=0; j<CURL_NUM_ACB; j++) {
 311                 if (!state->acb[j]) {
 312                     state->acb[j] = acb;
 313                     return FIND_RET_WAIT;
 314                 }
 315             }
 316         }
 317     }
 318
 319     return FIND_RET_NONE;
 320 }
 321
 322 static void curl_multi_check_completion(BDRVCURLState *s)
 323 {
 324     int msgs_in_queue;
 325
 326     /* Try to find done transfers, so we can free the easy
 327      * handle again. */
 328     for (;;) {
 329         CURLMsg *msg;
 330         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 331
 332         /* Quit when there are no more completions */
 333         if (!msg)
 334             break;
 335
 336         if (msg->msg == CURLMSG_DONE) {
 337             CURLState *state = NULL;
 338             curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
 339                               (char **)&state);
 340
 341             /* ACBs for successful messages get completed in curl_read_cb */
 342             if (msg->data.result != CURLE_OK) {
 343                 int i;
 344                 static int errcount = 100;
 345
 346                 /* Don't lose the original error message from curl, since
 347                  * it contains extra data.
 348                  */
 349                 if (errcount > 0) {
 350                     error_report("curl: %s", state->errmsg);
 351                     if (--errcount == 0) {
 352                         error_report("curl: further errors suppressed");
 353                     }
 354                 }
 355
 356                 for (i = 0; i < CURL_NUM_ACB; i++) {
 357                     CURLAIOCB *acb = state->acb[i];
 358
 359                     if (acb == NULL) {
 360                         continue;
 361                     }
 362
 363                     acb->common.cb(acb->common.opaque, -EPROTO);
 364                     qemu_aio_unref(acb);
 365                     state->acb[i] = NULL;
 366                 }
 367             }
 368
 369             curl_clean_state(state);
 370             break;
 371         }
 372     }
 373 }
 374
 375 static void curl_multi_do(void *arg)
 376 {
 377     CURLState *s = (CURLState *)arg;
 378     CURLSocket *socket, *next_socket;
 379     int running;
 380     int r;
 381
 382     if (!s->s->multi) {
 383         return;
 384     }
 385
 386     /* Need to use _SAFE because curl_multi_socket_action() may trigger
 387      * curl_sock_cb() which might modify this list */
 388     QLIST_FOREACH_SAFE(socket, &s->sockets, next, next_socket) {
 389         do {
 390             r = curl_multi_socket_action(s->s->multi, socket->fd, 0, &running);
 391         } while (r == CURLM_CALL_MULTI_PERFORM);
 392     }
 393 }
 394
 395 static void curl_multi_read(void *arg)
 396 {
 397     CURLState *s = (CURLState *)arg;
 398
 399     curl_multi_do(arg);
 400     curl_multi_check_completion(s->s);
 401 }
 402
 403 static void curl_multi_timeout_do(void *arg)
 404 {
 405 #ifdef NEED_CURL_TIMER_CALLBACK
 406     BDRVCURLState *s = (BDRVCURLState *)arg;
 407     int running;
 408
 409     if (!s->multi) {
 410         return;
 411     }
 412
 413     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 414
 415     curl_multi_check_completion(s);
 416 #else
 417     abort();
 418 #endif
 419 }
 420
 421 static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
 422 {
 423     CURLState *state = NULL;
 424     int i, j;
 425
 426     do {
 427         for (i=0; i<CURL_NUM_STATES; i++) {
 428             for (j=0; j<CURL_NUM_ACB; j++)
 429                 if (s->states[i].acb[j])
 430                     continue;
 431             if (s->states[i].in_use)
 432                 continue;
 433
 434             state = &s->states[i];
 435             state->in_use = 1;
 436             break;
 437         }
 438         if (!state) {
 439             aio_poll(bdrv_get_aio_context(bs), true);
 440         }
 441     } while(!state);
 442
 443     if (!state->curl) {
 444         state->curl = curl_easy_init();
 445         if (!state->curl) {
 446             return NULL;
 447         }
 448         curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
 449         curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
 450                          (long) s->sslverify);
 451         if (s->cookie) {
 452             curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
 453         }
 454         curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
 455         curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
 456                          (void *)curl_read_cb);
 457         curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
 458         curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
 459         curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
 460         curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
 461         curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
 462         curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
 463         curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 464
 465         if (s->username) {
 466             curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
 467         }
 468         if (s->password) {
 469             curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
 470         }
 471         if (s->proxyusername) {
 472             curl_easy_setopt(state->curl,
 473                              CURLOPT_PROXYUSERNAME, s->proxyusername);
 474         }
 475         if (s->proxypassword) {
 476             curl_easy_setopt(state->curl,
 477                              CURLOPT_PROXYPASSWORD, s->proxypassword);
 478         }
 479
 480         /* Restrict supported protocols to avoid security issues in the more
 481          * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
 482          * CVE-2013-0249.
 483          *
 484          * Restricting protocols is only supported from 7.19.4 upwards.
 485          */
 486 #if LIBCURL_VERSION_NUM >= 0x071304
 487         curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
 488         curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
 489 #endif
 490
 491 #ifdef DEBUG_VERBOSE
 492         curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
 493 #endif
 494     }
 495
 496     QLIST_INIT(&state->sockets);
 497     state->s = s;
 498
 499     return state;
 500 }
 501
 502 static void curl_clean_state(CURLState *s)
 503 {
 504     if (s->s->multi)
 505         curl_multi_remove_handle(s->s->multi, s->curl);
 506
 507     while (!QLIST_EMPTY(&s->sockets)) {
 508         CURLSocket *socket = QLIST_FIRST(&s->sockets);
 509
 510         QLIST_REMOVE(socket, next);
 511         g_free(socket);
 512     }
 513
 514     s->in_use = 0;
 515 }
 516
 517 static void curl_parse_filename(const char *filename, QDict *options,
 518                                 Error **errp)
 519 {
 520     qdict_put(options, CURL_BLOCK_OPT_URL, qstring_from_str(filename));
 521 }
 522
 523 static void curl_detach_aio_context(BlockDriverState *bs)
 524 {
 525     BDRVCURLState *s = bs->opaque;
 526     int i;
 527
 528     for (i = 0; i < CURL_NUM_STATES; i++) {
 529         if (s->states[i].in_use) {
 530             curl_clean_state(&s->states[i]);
 531         }
 532         if (s->states[i].curl) {
 533             curl_easy_cleanup(s->states[i].curl);
 534             s->states[i].curl = NULL;
 535         }
 536         g_free(s->states[i].orig_buf);
 537         s->states[i].orig_buf = NULL;
 538     }
 539     if (s->multi) {
 540         curl_multi_cleanup(s->multi);
 541         s->multi = NULL;
 542     }
 543
 544     timer_del(&s->timer);
 545 }
 546
 547 static void curl_attach_aio_context(BlockDriverState *bs,
 548                                     AioContext *new_context)
 549 {
 550     BDRVCURLState *s = bs->opaque;
 551
 552     aio_timer_init(new_context, &s->timer,
 553                    QEMU_CLOCK_REALTIME, SCALE_NS,
 554                    curl_multi_timeout_do, s);
 555
 556     assert(!s->multi);
 557     s->multi = curl_multi_init();
 558     s->aio_context = new_context;
 559     curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
 560 #ifdef NEED_CURL_TIMER_CALLBACK
 561     curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
 562     curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
 563 #endif
 564 }
 565
 566 static QemuOptsList runtime_opts = {
 567     .name = "curl",
 568     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 569     .desc = {
 570         {
 571             .name = CURL_BLOCK_OPT_URL,
 572             .type = QEMU_OPT_STRING,
 573             .help = "URL to open",
 574         },
 575         {
 576             .name = CURL_BLOCK_OPT_READAHEAD,
 577             .type = QEMU_OPT_SIZE,
 578             .help = "Readahead size",
 579         },
 580         {
 581             .name = CURL_BLOCK_OPT_SSLVERIFY,
 582             .type = QEMU_OPT_BOOL,
 583             .help = "Verify SSL certificate"
 584         },
 585         {
 586             .name = CURL_BLOCK_OPT_TIMEOUT,
 587             .type = QEMU_OPT_NUMBER,
 588             .help = "Curl timeout"
 589         },
 590         {
 591             .name = CURL_BLOCK_OPT_COOKIE,
 592             .type = QEMU_OPT_STRING,
 593             .help = "Pass the cookie or list of cookies with each request"
 594         },
 595         {
 596             .name = CURL_BLOCK_OPT_USERNAME,
 597             .type = QEMU_OPT_STRING,
 598             .help = "Username for HTTP auth"
 599         },
 600         {
 601             .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
 602             .type = QEMU_OPT_STRING,
 603             .help = "ID of secret used as password for HTTP auth",
 604         },
 605         {
 606             .name = CURL_BLOCK_OPT_PROXY_USERNAME,
 607             .type = QEMU_OPT_STRING,
 608             .help = "Username for HTTP proxy auth"
 609         },
 610         {
 611             .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
 612             .type = QEMU_OPT_STRING,
 613             .help = "ID of secret used as password for HTTP proxy auth",
 614         },
 615         { /* end of list */ }
 616     },
 617 };
 618
 619
 620 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 621                      Error **errp)
 622 {
 623     BDRVCURLState *s = bs->opaque;
 624     CURLState *state = NULL;
 625     QemuOpts *opts;
 626     Error *local_err = NULL;
 627     const char *file;
 628     const char *cookie;
 629     double d;
 630     const char *secretid;
 631
 632     static int inited = 0;
 633
 634     if (flags & BDRV_O_RDWR) {
 635         error_setg(errp, "curl block device does not support writes");
 636         return -EROFS;
 637     }
 638
 639     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 640     qemu_opts_absorb_qdict(opts, options, &local_err);
 641     if (local_err) {
 642         error_propagate(errp, local_err);
 643         goto out_noclean;
 644     }
 645
 646     s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
 647                                           READ_AHEAD_DEFAULT);
 648     if ((s->readahead_size & 0x1ff) != 0) {
 649         error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
 650                    s->readahead_size);
 651         goto out_noclean;
 652     }
 653
 654     s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
 655                                      CURL_TIMEOUT_DEFAULT);
 656     if (s->timeout > CURL_TIMEOUT_MAX) {
 657         error_setg(errp, "timeout parameter is too large or negative");
 658         goto out_noclean;
 659     }
 660
 661     s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
 662
 663     cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
 664     s->cookie = g_strdup(cookie);
 665
 666     file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
 667     if (file == NULL) {
 668         error_setg(errp, "curl block driver requires an 'url' option");
 669         goto out_noclean;
 670     }
 671
 672     s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
 673     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
 674
 675     if (secretid) {
 676         s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
 677         if (!s->password) {
 678             goto out_noclean;
 679         }
 680     }
 681
 682     s->proxyusername = g_strdup(
 683         qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
 684     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
 685     if (secretid) {
 686         s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
 687         if (!s->proxypassword) {
 688             goto out_noclean;
 689         }
 690     }
 691
 692     if (!inited) {
 693         curl_global_init(CURL_GLOBAL_ALL);
 694         inited = 1;
 695     }
 696
 697     DPRINTF("CURL: Opening %s\n", file);
 698     s->aio_context = bdrv_get_aio_context(bs);
 699     s->url = g_strdup(file);
 700     state = curl_init_state(bs, s);
 701     if (!state)
 702         goto out_noclean;
 703
 704     // Get file size
 705
 706     s->accept_range = false;
 707     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
 708     curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
 709                      curl_header_cb);
 710     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
 711     if (curl_easy_perform(state->curl))
 712         goto out;
 713     if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
 714         goto out;
 715     }
 716     /* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
 717      * know or the size is zero. From 7.19.4 CURL returns -1 if size is not
 718      * known and zero if it is realy zero-length file. */
 719 #if LIBCURL_VERSION_NUM >= 0x071304
 720     if (d < 0) {
 721         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 722                 "Server didn't report file size.");
 723         goto out;
 724     }
 725 #else
 726     if (d <= 0) {
 727         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 728                 "Unknown file size or zero-length file.");
 729         goto out;
 730     }
 731 #endif
 732
 733     s->len = (size_t)d;
 734
 735     if ((!strncasecmp(s->url, "http://", strlen("http://"))
 736         || !strncasecmp(s->url, "https://", strlen("https://")))
 737         && !s->accept_range) {
 738         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 739                 "Server does not support 'range' (byte ranges).");
 740         goto out;
 741     }
 742     DPRINTF("CURL: Size = %zd\n", s->len);
 743
 744     curl_clean_state(state);
 745     curl_easy_cleanup(state->curl);
 746     state->curl = NULL;
 747
 748     curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
 749
 750     qemu_opts_del(opts);
 751     return 0;
 752
 753 out:
 754     error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
 755     curl_easy_cleanup(state->curl);
 756     state->curl = NULL;
 757 out_noclean:
 758     g_free(s->cookie);
 759     g_free(s->url);
 760     qemu_opts_del(opts);
 761     return -EINVAL;
 762 }
 763
 764 static const AIOCBInfo curl_aiocb_info = {
 765     .aiocb_size         = sizeof(CURLAIOCB),
 766 };
 767
 768
 769 static void curl_readv_bh_cb(void *p)
 770 {
 771     CURLState *state;
 772     int running;
 773
 774     CURLAIOCB *acb = p;
 775     BDRVCURLState *s = acb->common.bs->opaque;
 776
 777     size_t start = acb->sector_num * BDRV_SECTOR_SIZE;
 778     size_t end;
 779
 780     // In case we have the requested data already (e.g. read-ahead),
 781     // we can just call the callback and be done.
 782     switch (curl_find_buf(s, start, acb->nb_sectors * BDRV_SECTOR_SIZE, acb)) {
 783         case FIND_RET_OK:
 784             qemu_aio_unref(acb);
 785             // fall through
 786         case FIND_RET_WAIT:
 787             return;
 788         default:
 789             break;
 790     }
 791
 792     // No cache found, so let's start a new request
 793     state = curl_init_state(acb->common.bs, s);
 794     if (!state) {
 795         acb->common.cb(acb->common.opaque, -EIO);
 796         qemu_aio_unref(acb);
 797         return;
 798     }
 799
 800     acb->start = 0;
 801     acb->end = (acb->nb_sectors * BDRV_SECTOR_SIZE);
 802
 803     state->buf_off = 0;
 804     g_free(state->orig_buf);
 805     state->buf_start = start;
 806     state->buf_len = acb->end + s->readahead_size;
 807     end = MIN(start + state->buf_len, s->len) - 1;
 808     state->orig_buf = g_try_malloc(state->buf_len);
 809     if (state->buf_len && state->orig_buf == NULL) {
 810         curl_clean_state(state);
 811         acb->common.cb(acb->common.opaque, -ENOMEM);
 812         qemu_aio_unref(acb);
 813         return;
 814     }
 815     state->acb[0] = acb;
 816
 817     snprintf(state->range, 127, "%zd-%zd", start, end);
 818     DPRINTF("CURL (AIO): Reading %llu at %zd (%s)\n",
 819             (acb->nb_sectors * BDRV_SECTOR_SIZE), start, state->range);
 820     curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
 821
 822     curl_multi_add_handle(s->multi, state->curl);
 823
 824     /* Tell curl it needs to kick things off */
 825     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 826 }
 827
 828 static BlockAIOCB *curl_aio_readv(BlockDriverState *bs,
 829         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 830         BlockCompletionFunc *cb, void *opaque)
 831 {
 832     CURLAIOCB *acb;
 833
 834     acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
 835
 836     acb->qiov = qiov;
 837     acb->sector_num = sector_num;
 838     acb->nb_sectors = nb_sectors;
 839
 840     aio_bh_schedule_oneshot(bdrv_get_aio_context(bs), curl_readv_bh_cb, acb);
 841     return &acb->common;
 842 }
 843
 844 static void curl_close(BlockDriverState *bs)
 845 {
 846     BDRVCURLState *s = bs->opaque;
 847
 848     DPRINTF("CURL: Close\n");
 849     curl_detach_aio_context(bs);
 850
 851     g_free(s->cookie);
 852     g_free(s->url);
 853 }
 854
 855 static int64_t curl_getlength(BlockDriverState *bs)
 856 {
 857     BDRVCURLState *s = bs->opaque;
 858     return s->len;
 859 }
 860
 861 static BlockDriver bdrv_http = {
 862     .format_name                = "http",
 863     .protocol_name              = "http",
 864
 865     .instance_size              = sizeof(BDRVCURLState),
 866     .bdrv_parse_filename        = curl_parse_filename,
 867     .bdrv_file_open             = curl_open,
 868     .bdrv_close                 = curl_close,
 869     .bdrv_getlength             = curl_getlength,
 870
 871     .bdrv_aio_readv             = curl_aio_readv,
 872
 873     .bdrv_detach_aio_context    = curl_detach_aio_context,
 874     .bdrv_attach_aio_context    = curl_attach_aio_context,
 875 };
 876
 877 static BlockDriver bdrv_https = {
 878     .format_name                = "https",
 879     .protocol_name              = "https",
 880
 881     .instance_size              = sizeof(BDRVCURLState),
 882     .bdrv_parse_filename        = curl_parse_filename,
 883     .bdrv_file_open             = curl_open,
 884     .bdrv_close                 = curl_close,
 885     .bdrv_getlength             = curl_getlength,
 886
 887     .bdrv_aio_readv             = curl_aio_readv,
 888
 889     .bdrv_detach_aio_context    = curl_detach_aio_context,
 890     .bdrv_attach_aio_context    = curl_attach_aio_context,
 891 };
 892
 893 static BlockDriver bdrv_ftp = {
 894     .format_name                = "ftp",
 895     .protocol_name              = "ftp",
 896
 897     .instance_size              = sizeof(BDRVCURLState),
 898     .bdrv_parse_filename        = curl_parse_filename,
 899     .bdrv_file_open             = curl_open,
 900     .bdrv_close                 = curl_close,
 901     .bdrv_getlength             = curl_getlength,
 902
 903     .bdrv_aio_readv             = curl_aio_readv,
 904
 905     .bdrv_detach_aio_context    = curl_detach_aio_context,
 906     .bdrv_attach_aio_context    = curl_attach_aio_context,
 907 };
 908
 909 static BlockDriver bdrv_ftps = {
 910     .format_name                = "ftps",
 911     .protocol_name              = "ftps",
 912
 913     .instance_size              = sizeof(BDRVCURLState),
 914     .bdrv_parse_filename        = curl_parse_filename,
 915     .bdrv_file_open             = curl_open,
 916     .bdrv_close                 = curl_close,
 917     .bdrv_getlength             = curl_getlength,
 918
 919     .bdrv_aio_readv             = curl_aio_readv,
 920
 921     .bdrv_detach_aio_context    = curl_detach_aio_context,
 922     .bdrv_attach_aio_context    = curl_attach_aio_context,
 923 };
 924
 925 static void curl_block_init(void)
 926 {
 927     bdrv_register(&bdrv_http);
 928     bdrv_register(&bdrv_https);
 929     bdrv_register(&bdrv_ftp);
 930     bdrv_register(&bdrv_ftps);
 931 }
 932
 933 block_init(curl_block_init);