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