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
  25#include "qemu/osdep.h"
  26#include "qapi/error.h"
  27#include "qemu/error-report.h"
  28#include "qemu/module.h"
  29#include "qemu/option.h"
  30#include "block/block_int.h"
  31#include "qapi/qmp/qdict.h"
  32#include "qapi/qmp/qstring.h"
  33#include "crypto/secret.h"
  34#include <curl/curl.h>
  35#include "qemu/cutils.h"
  36#include "trace.h"
  37
  38// #define DEBUG_VERBOSE
  39
  40#define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
  41                   CURLPROTO_FTP | CURLPROTO_FTPS)
  42
  43#define CURL_NUM_STATES 8
  44#define CURL_NUM_ACB    8
  45#define CURL_TIMEOUT_MAX 10000
  46
  47#define CURL_BLOCK_OPT_URL       "url"
  48#define CURL_BLOCK_OPT_READAHEAD "readahead"
  49#define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
  50#define CURL_BLOCK_OPT_TIMEOUT "timeout"
  51#define CURL_BLOCK_OPT_COOKIE    "cookie"
  52#define CURL_BLOCK_OPT_COOKIE_SECRET "cookie-secret"
  53#define CURL_BLOCK_OPT_USERNAME "username"
  54#define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
  55#define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
  56#define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
  57
  58#define CURL_BLOCK_OPT_READAHEAD_DEFAULT (256 * 1024)
  59#define CURL_BLOCK_OPT_SSLVERIFY_DEFAULT true
  60#define CURL_BLOCK_OPT_TIMEOUT_DEFAULT 5
  61
  62struct BDRVCURLState;
  63struct CURLState;
  64
  65static bool libcurl_initialized;
  66
  67typedef struct CURLAIOCB {
  68    Coroutine *co;
  69    QEMUIOVector *qiov;
  70
  71    uint64_t offset;
  72    uint64_t bytes;
  73    int ret;
  74
  75    size_t start;
  76    size_t end;
  77} CURLAIOCB;
  78
  79typedef struct CURLSocket {
  80    int fd;
  81    struct BDRVCURLState *s;
  82} CURLSocket;
  83
  84typedef struct CURLState
  85{
  86    struct BDRVCURLState *s;
  87    CURLAIOCB *acb[CURL_NUM_ACB];
  88    CURL *curl;
  89    char *orig_buf;
  90    uint64_t buf_start;
  91    size_t buf_off;
  92    size_t buf_len;
  93    char range[128];
  94    char errmsg[CURL_ERROR_SIZE];
  95    char in_use;
  96} CURLState;
  97
  98typedef struct BDRVCURLState {
  99    CURLM *multi;
 100    QEMUTimer timer;
 101    uint64_t len;
 102    CURLState states[CURL_NUM_STATES];
 103    GHashTable *sockets; /* GINT_TO_POINTER(fd) -> socket */
 104    char *url;
 105    size_t readahead_size;
 106    bool sslverify;
 107    uint64_t timeout;
 108    char *cookie;
 109    bool accept_range;
 110    AioContext *aio_context;
 111    QemuMutex mutex;
 112    CoQueue free_state_waitq;
 113    char *username;
 114    char *password;
 115    char *proxyusername;
 116    char *proxypassword;
 117} BDRVCURLState;
 118
 119static void curl_clean_state(CURLState *s);
 120static void curl_multi_do(void *arg);
 121
 122static gboolean curl_drop_socket(void *key, void *value, void *opaque)
 123{
 124    CURLSocket *socket = value;
 125    BDRVCURLState *s = socket->s;
 126
 127    aio_set_fd_handler(s->aio_context, socket->fd, false,
 128                       NULL, NULL, NULL, NULL);
 129    return true;
 130}
 131
 132static void curl_drop_all_sockets(GHashTable *sockets)
 133{
 134    g_hash_table_foreach_remove(sockets, curl_drop_socket, NULL);
 135}
 136
 137/* Called from curl_multi_do_locked, with s->mutex held.  */
 138static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
 139{
 140    BDRVCURLState *s = opaque;
 141
 142    trace_curl_timer_cb(timeout_ms);
 143    if (timeout_ms == -1) {
 144        timer_del(&s->timer);
 145    } else {
 146        int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
 147        timer_mod(&s->timer,
 148                  qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
 149    }
 150    return 0;
 151}
 152
 153/* Called from curl_multi_do_locked, with s->mutex held.  */
 154static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 155                        void *userp, void *sp)
 156{
 157    BDRVCURLState *s;
 158    CURLState *state = NULL;
 159    CURLSocket *socket;
 160
 161    curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
 162    s = state->s;
 163
 164    socket = g_hash_table_lookup(s->sockets, GINT_TO_POINTER(fd));
 165    if (!socket) {
 166        socket = g_new0(CURLSocket, 1);
 167        socket->fd = fd;
 168        socket->s = s;
 169        g_hash_table_insert(s->sockets, GINT_TO_POINTER(fd), socket);
 170    }
 171
 172    trace_curl_sock_cb(action, (int)fd);
 173    switch (action) {
 174        case CURL_POLL_IN:
 175            aio_set_fd_handler(s->aio_context, fd, false,
 176                               curl_multi_do, NULL, NULL, socket);
 177            break;
 178        case CURL_POLL_OUT:
 179            aio_set_fd_handler(s->aio_context, fd, false,
 180                               NULL, curl_multi_do, NULL, socket);
 181            break;
 182        case CURL_POLL_INOUT:
 183            aio_set_fd_handler(s->aio_context, fd, false,
 184                               curl_multi_do, curl_multi_do, NULL, socket);
 185            break;
 186        case CURL_POLL_REMOVE:
 187            aio_set_fd_handler(s->aio_context, fd, false,
 188                               NULL, NULL, NULL, NULL);
 189            break;
 190    }
 191
 192    if (action == CURL_POLL_REMOVE) {
 193        g_hash_table_remove(s->sockets, GINT_TO_POINTER(fd));
 194    }
 195
 196    return 0;
 197}
 198
 199/* Called from curl_multi_do_locked, with s->mutex held.  */
 200static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 201{
 202    BDRVCURLState *s = opaque;
 203    size_t realsize = size * nmemb;
 204    const char *header = (char *)ptr;
 205    const char *end = header + realsize;
 206    const char *accept_ranges = "accept-ranges:";
 207    const char *bytes = "bytes";
 208
 209    if (realsize >= strlen(accept_ranges)
 210        && g_ascii_strncasecmp(header, accept_ranges,
 211                               strlen(accept_ranges)) == 0) {
 212
 213        char *p = strchr(header, ':') + 1;
 214
 215        /* Skip whitespace between the header name and value. */
 216        while (p < end && *p && g_ascii_isspace(*p)) {
 217            p++;
 218        }
 219
 220        if (end - p >= strlen(bytes)
 221            && strncmp(p, bytes, strlen(bytes)) == 0) {
 222
 223            /* Check that there is nothing but whitespace after the value. */
 224            p += strlen(bytes);
 225            while (p < end && *p && g_ascii_isspace(*p)) {
 226                p++;
 227            }
 228
 229            if (p == end || !*p) {
 230                s->accept_range = true;
 231            }
 232        }
 233    }
 234
 235    return realsize;
 236}
 237
 238/* Called from curl_multi_do_locked, with s->mutex held.  */
 239static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 240{
 241    CURLState *s = ((CURLState*)opaque);
 242    size_t realsize = size * nmemb;
 243
 244    trace_curl_read_cb(realsize);
 245
 246    if (!s || !s->orig_buf) {
 247        goto read_end;
 248    }
 249
 250    if (s->buf_off >= s->buf_len) {
 251        /* buffer full, read nothing */
 252        goto read_end;
 253    }
 254    realsize = MIN(realsize, s->buf_len - s->buf_off);
 255    memcpy(s->orig_buf + s->buf_off, ptr, realsize);
 256    s->buf_off += realsize;
 257
 258read_end:
 259    /* curl will error out if we do not return this value */
 260    return size * nmemb;
 261}
 262
 263/* Called with s->mutex held.  */
 264static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
 265                          CURLAIOCB *acb)
 266{
 267    int i;
 268    uint64_t end = start + len;
 269    uint64_t clamped_end = MIN(end, s->len);
 270    uint64_t clamped_len = clamped_end - start;
 271
 272    for (i=0; i<CURL_NUM_STATES; i++) {
 273        CURLState *state = &s->states[i];
 274        uint64_t buf_end = (state->buf_start + state->buf_off);
 275        uint64_t buf_fend = (state->buf_start + state->buf_len);
 276
 277        if (!state->orig_buf)
 278            continue;
 279        if (!state->buf_off)
 280            continue;
 281
 282        // Does the existing buffer cover our section?
 283        if ((start >= state->buf_start) &&
 284            (start <= buf_end) &&
 285            (clamped_end >= state->buf_start) &&
 286            (clamped_end <= buf_end))
 287        {
 288            char *buf = state->orig_buf + (start - state->buf_start);
 289
 290            qemu_iovec_from_buf(acb->qiov, 0, buf, clamped_len);
 291            if (clamped_len < len) {
 292                qemu_iovec_memset(acb->qiov, clamped_len, 0, len - clamped_len);
 293            }
 294            acb->ret = 0;
 295            return true;
 296        }
 297
 298        // Wait for unfinished chunks
 299        if (state->in_use &&
 300            (start >= state->buf_start) &&
 301            (start <= buf_fend) &&
 302            (clamped_end >= state->buf_start) &&
 303            (clamped_end <= buf_fend))
 304        {
 305            int j;
 306
 307            acb->start = start - state->buf_start;
 308            acb->end = acb->start + clamped_len;
 309
 310            for (j=0; j<CURL_NUM_ACB; j++) {
 311                if (!state->acb[j]) {
 312                    state->acb[j] = acb;
 313                    return true;
 314                }
 315            }
 316        }
 317    }
 318
 319    return false;
 320}
 321
 322/* Called with s->mutex held.  */
 323static void curl_multi_check_completion(BDRVCURLState *s)
 324{
 325    int msgs_in_queue;
 326
 327    /* Try to find done transfers, so we can free the easy
 328     * handle again. */
 329    for (;;) {
 330        CURLMsg *msg;
 331        msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 332
 333        /* Quit when there are no more completions */
 334        if (!msg)
 335            break;
 336
 337        if (msg->msg == CURLMSG_DONE) {
 338            int i;
 339            CURLState *state = NULL;
 340            bool error = msg->data.result != CURLE_OK;
 341
 342            curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
 343                              (char **)&state);
 344
 345            if (error) {
 346                static int errcount = 100;
 347
 348                /* Don't lose the original error message from curl, since
 349                 * it contains extra data.
 350                 */
 351                if (errcount > 0) {
 352                    error_report("curl: %s", state->errmsg);
 353                    if (--errcount == 0) {
 354                        error_report("curl: further errors suppressed");
 355                    }
 356                }
 357            }
 358
 359            for (i = 0; i < CURL_NUM_ACB; i++) {
 360                CURLAIOCB *acb = state->acb[i];
 361
 362                if (acb == NULL) {
 363                    continue;
 364                }
 365
 366                if (!error) {
 367                    /* Assert that we have read all data */
 368                    assert(state->buf_off >= acb->end);
 369
 370                    qemu_iovec_from_buf(acb->qiov, 0,
 371                                        state->orig_buf + acb->start,
 372                                        acb->end - acb->start);
 373
 374                    if (acb->end - acb->start < acb->bytes) {
 375                        size_t offset = acb->end - acb->start;
 376                        qemu_iovec_memset(acb->qiov, offset, 0,
 377                                          acb->bytes - offset);
 378                    }
 379                }
 380
 381                acb->ret = error ? -EIO : 0;
 382                state->acb[i] = NULL;
 383                qemu_mutex_unlock(&s->mutex);
 384                aio_co_wake(acb->co);
 385                qemu_mutex_lock(&s->mutex);
 386            }
 387
 388            curl_clean_state(state);
 389            break;
 390        }
 391    }
 392}
 393
 394/* Called with s->mutex held.  */
 395static void curl_multi_do_locked(CURLSocket *socket)
 396{
 397    BDRVCURLState *s = socket->s;
 398    int running;
 399    int r;
 400
 401    if (!s->multi) {
 402        return;
 403    }
 404
 405    do {
 406        r = curl_multi_socket_action(s->multi, socket->fd, 0, &running);
 407    } while (r == CURLM_CALL_MULTI_PERFORM);
 408}
 409
 410static void curl_multi_do(void *arg)
 411{
 412    CURLSocket *socket = arg;
 413    BDRVCURLState *s = socket->s;
 414
 415    qemu_mutex_lock(&s->mutex);
 416    curl_multi_do_locked(socket);
 417    curl_multi_check_completion(s);
 418    qemu_mutex_unlock(&s->mutex);
 419}
 420
 421static void curl_multi_timeout_do(void *arg)
 422{
 423    BDRVCURLState *s = (BDRVCURLState *)arg;
 424    int running;
 425
 426    if (!s->multi) {
 427        return;
 428    }
 429
 430    qemu_mutex_lock(&s->mutex);
 431    curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 432
 433    curl_multi_check_completion(s);
 434    qemu_mutex_unlock(&s->mutex);
 435}
 436
 437/* Called with s->mutex held.  */
 438static CURLState *curl_find_state(BDRVCURLState *s)
 439{
 440    CURLState *state = NULL;
 441    int i;
 442
 443    for (i = 0; i < CURL_NUM_STATES; i++) {
 444        if (!s->states[i].in_use) {
 445            state = &s->states[i];
 446            state->in_use = 1;
 447            break;
 448        }
 449    }
 450    return state;
 451}
 452
 453static int curl_init_state(BDRVCURLState *s, CURLState *state)
 454{
 455    if (!state->curl) {
 456        state->curl = curl_easy_init();
 457        if (!state->curl) {
 458            return -EIO;
 459        }
 460        curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
 461        curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
 462                         (long) s->sslverify);
 463        curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYHOST,
 464                         s->sslverify ? 2L : 0L);
 465        if (s->cookie) {
 466            curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
 467        }
 468        curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
 469        curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
 470                         (void *)curl_read_cb);
 471        curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
 472        curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
 473        curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
 474        curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
 475        curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
 476        curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
 477        curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 478
 479        if (s->username) {
 480            curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
 481        }
 482        if (s->password) {
 483            curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
 484        }
 485        if (s->proxyusername) {
 486            curl_easy_setopt(state->curl,
 487                             CURLOPT_PROXYUSERNAME, s->proxyusername);
 488        }
 489        if (s->proxypassword) {
 490            curl_easy_setopt(state->curl,
 491                             CURLOPT_PROXYPASSWORD, s->proxypassword);
 492        }
 493
 494        /* Restrict supported protocols to avoid security issues in the more
 495         * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
 496         * CVE-2013-0249.
 497         *
 498         * Restricting protocols is only supported from 7.19.4 upwards.
 499         */
 500#if LIBCURL_VERSION_NUM >= 0x071304
 501        curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
 502        curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
 503#endif
 504
 505#ifdef DEBUG_VERBOSE
 506        curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
 507#endif
 508    }
 509
 510    state->s = s;
 511
 512    return 0;
 513}
 514
 515/* Called with s->mutex held.  */
 516static void curl_clean_state(CURLState *s)
 517{
 518    int j;
 519    for (j = 0; j < CURL_NUM_ACB; j++) {
 520        assert(!s->acb[j]);
 521    }
 522
 523    if (s->s->multi)
 524        curl_multi_remove_handle(s->s->multi, s->curl);
 525
 526    s->in_use = 0;
 527
 528    qemu_co_enter_next(&s->s->free_state_waitq, &s->s->mutex);
 529}
 530
 531static void curl_parse_filename(const char *filename, QDict *options,
 532                                Error **errp)
 533{
 534    qdict_put_str(options, CURL_BLOCK_OPT_URL, filename);
 535}
 536
 537static void curl_detach_aio_context(BlockDriverState *bs)
 538{
 539    BDRVCURLState *s = bs->opaque;
 540    int i;
 541
 542    WITH_QEMU_LOCK_GUARD(&s->mutex) {
 543        curl_drop_all_sockets(s->sockets);
 544        for (i = 0; i < CURL_NUM_STATES; i++) {
 545            if (s->states[i].in_use) {
 546                curl_clean_state(&s->states[i]);
 547            }
 548            if (s->states[i].curl) {
 549                curl_easy_cleanup(s->states[i].curl);
 550                s->states[i].curl = NULL;
 551            }
 552            g_free(s->states[i].orig_buf);
 553            s->states[i].orig_buf = NULL;
 554        }
 555        if (s->multi) {
 556            curl_multi_cleanup(s->multi);
 557            s->multi = NULL;
 558        }
 559    }
 560
 561    timer_del(&s->timer);
 562}
 563
 564static void curl_attach_aio_context(BlockDriverState *bs,
 565                                    AioContext *new_context)
 566{
 567    BDRVCURLState *s = bs->opaque;
 568
 569    aio_timer_init(new_context, &s->timer,
 570                   QEMU_CLOCK_REALTIME, SCALE_NS,
 571                   curl_multi_timeout_do, s);
 572
 573    assert(!s->multi);
 574    s->multi = curl_multi_init();
 575    s->aio_context = new_context;
 576    curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
 577    curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
 578    curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
 579}
 580
 581static QemuOptsList runtime_opts = {
 582    .name = "curl",
 583    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 584    .desc = {
 585        {
 586            .name = CURL_BLOCK_OPT_URL,
 587            .type = QEMU_OPT_STRING,
 588            .help = "URL to open",
 589        },
 590        {
 591            .name = CURL_BLOCK_OPT_READAHEAD,
 592            .type = QEMU_OPT_SIZE,
 593            .help = "Readahead size",
 594        },
 595        {
 596            .name = CURL_BLOCK_OPT_SSLVERIFY,
 597            .type = QEMU_OPT_BOOL,
 598            .help = "Verify SSL certificate"
 599        },
 600        {
 601            .name = CURL_BLOCK_OPT_TIMEOUT,
 602            .type = QEMU_OPT_NUMBER,
 603            .help = "Curl timeout"
 604        },
 605        {
 606            .name = CURL_BLOCK_OPT_COOKIE,
 607            .type = QEMU_OPT_STRING,
 608            .help = "Pass the cookie or list of cookies with each request"
 609        },
 610        {
 611            .name = CURL_BLOCK_OPT_COOKIE_SECRET,
 612            .type = QEMU_OPT_STRING,
 613            .help = "ID of secret used as cookie passed with each request"
 614        },
 615        {
 616            .name = CURL_BLOCK_OPT_USERNAME,
 617            .type = QEMU_OPT_STRING,
 618            .help = "Username for HTTP auth"
 619        },
 620        {
 621            .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
 622            .type = QEMU_OPT_STRING,
 623            .help = "ID of secret used as password for HTTP auth",
 624        },
 625        {
 626            .name = CURL_BLOCK_OPT_PROXY_USERNAME,
 627            .type = QEMU_OPT_STRING,
 628            .help = "Username for HTTP proxy auth"
 629        },
 630        {
 631            .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
 632            .type = QEMU_OPT_STRING,
 633            .help = "ID of secret used as password for HTTP proxy auth",
 634        },
 635        { /* end of list */ }
 636    },
 637};
 638
 639
 640static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 641                     Error **errp)
 642{
 643    BDRVCURLState *s = bs->opaque;
 644    CURLState *state = NULL;
 645    QemuOpts *opts;
 646    const char *file;
 647    const char *cookie;
 648    const char *cookie_secret;
 649    double d;
 650    const char *secretid;
 651    const char *protocol_delimiter;
 652    int ret;
 653
 654    ret = bdrv_apply_auto_read_only(bs, "curl driver does not support writes",
 655                                    errp);
 656    if (ret < 0) {
 657        return ret;
 658    }
 659
 660    if (!libcurl_initialized) {
 661        ret = curl_global_init(CURL_GLOBAL_ALL);
 662        if (ret) {
 663            error_setg(errp, "libcurl initialization failed with %d", ret);
 664            return -EIO;
 665        }
 666        libcurl_initialized = true;
 667    }
 668
 669    qemu_mutex_init(&s->mutex);
 670    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 671    if (!qemu_opts_absorb_qdict(opts, options, errp)) {
 672        goto out_noclean;
 673    }
 674
 675    s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
 676                                          CURL_BLOCK_OPT_READAHEAD_DEFAULT);
 677    if ((s->readahead_size & 0x1ff) != 0) {
 678        error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
 679                   s->readahead_size);
 680        goto out_noclean;
 681    }
 682
 683    s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
 684                                     CURL_BLOCK_OPT_TIMEOUT_DEFAULT);
 685    if (s->timeout > CURL_TIMEOUT_MAX) {
 686        error_setg(errp, "timeout parameter is too large or negative");
 687        goto out_noclean;
 688    }
 689
 690    s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY,
 691                                     CURL_BLOCK_OPT_SSLVERIFY_DEFAULT);
 692
 693    cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
 694    cookie_secret = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE_SECRET);
 695
 696    if (cookie && cookie_secret) {
 697        error_setg(errp,
 698                   "curl driver cannot handle both cookie and cookie secret");
 699        goto out_noclean;
 700    }
 701
 702    if (cookie_secret) {
 703        s->cookie = qcrypto_secret_lookup_as_utf8(cookie_secret, errp);
 704        if (!s->cookie) {
 705            goto out_noclean;
 706        }
 707    } else {
 708        s->cookie = g_strdup(cookie);
 709    }
 710
 711    file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
 712    if (file == NULL) {
 713        error_setg(errp, "curl block driver requires an 'url' option");
 714        goto out_noclean;
 715    }
 716
 717    if (!strstart(file, bs->drv->protocol_name, &protocol_delimiter) ||
 718        !strstart(protocol_delimiter, "://", NULL))
 719    {
 720        error_setg(errp, "%s curl driver cannot handle the URL '%s' (does not "
 721                   "start with '%s://')", bs->drv->protocol_name, file,
 722                   bs->drv->protocol_name);
 723        goto out_noclean;
 724    }
 725
 726    s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
 727    secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
 728
 729    if (secretid) {
 730        s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
 731        if (!s->password) {
 732            goto out_noclean;
 733        }
 734    }
 735
 736    s->proxyusername = g_strdup(
 737        qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
 738    secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
 739    if (secretid) {
 740        s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
 741        if (!s->proxypassword) {
 742            goto out_noclean;
 743        }
 744    }
 745
 746    trace_curl_open(file);
 747    qemu_co_queue_init(&s->free_state_waitq);
 748    s->aio_context = bdrv_get_aio_context(bs);
 749    s->url = g_strdup(file);
 750    s->sockets = g_hash_table_new_full(NULL, NULL, NULL, g_free);
 751    qemu_mutex_lock(&s->mutex);
 752    state = curl_find_state(s);
 753    qemu_mutex_unlock(&s->mutex);
 754    if (!state) {
 755        goto out_noclean;
 756    }
 757
 758    // Get file size
 759
 760    if (curl_init_state(s, state) < 0) {
 761        goto out;
 762    }
 763
 764    s->accept_range = false;
 765    curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
 766    curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
 767                     curl_header_cb);
 768    curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
 769    if (curl_easy_perform(state->curl))
 770        goto out;
 771    if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
 772        goto out;
 773    }
 774    /* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
 775     * know or the size is zero. From 7.19.4 CURL returns -1 if size is not
 776     * known and zero if it is really zero-length file. */
 777#if LIBCURL_VERSION_NUM >= 0x071304
 778    if (d < 0) {
 779        pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 780                "Server didn't report file size.");
 781        goto out;
 782    }
 783#else
 784    if (d <= 0) {
 785        pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 786                "Unknown file size or zero-length file.");
 787        goto out;
 788    }
 789#endif
 790
 791    s->len = d;
 792
 793    if ((!strncasecmp(s->url, "http://", strlen("http://"))
 794        || !strncasecmp(s->url, "https://", strlen("https://")))
 795        && !s->accept_range) {
 796        pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 797                "Server does not support 'range' (byte ranges).");
 798        goto out;
 799    }
 800    trace_curl_open_size(s->len);
 801
 802    qemu_mutex_lock(&s->mutex);
 803    curl_clean_state(state);
 804    qemu_mutex_unlock(&s->mutex);
 805    curl_easy_cleanup(state->curl);
 806    state->curl = NULL;
 807
 808    curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
 809
 810    qemu_opts_del(opts);
 811    return 0;
 812
 813out:
 814    error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
 815    curl_easy_cleanup(state->curl);
 816    state->curl = NULL;
 817out_noclean:
 818    qemu_mutex_destroy(&s->mutex);
 819    g_free(s->cookie);
 820    g_free(s->url);
 821    g_free(s->username);
 822    g_free(s->proxyusername);
 823    g_free(s->proxypassword);
 824    curl_drop_all_sockets(s->sockets);
 825    g_hash_table_destroy(s->sockets);
 826    qemu_opts_del(opts);
 827    return -EINVAL;
 828}
 829
 830static void curl_setup_preadv(BlockDriverState *bs, CURLAIOCB *acb)
 831{
 832    CURLState *state;
 833    int running;
 834
 835    BDRVCURLState *s = bs->opaque;
 836
 837    uint64_t start = acb->offset;
 838    uint64_t end;
 839
 840    qemu_mutex_lock(&s->mutex);
 841
 842    // In case we have the requested data already (e.g. read-ahead),
 843    // we can just call the callback and be done.
 844    if (curl_find_buf(s, start, acb->bytes, acb)) {
 845        goto out;
 846    }
 847
 848    // No cache found, so let's start a new request
 849    for (;;) {
 850        state = curl_find_state(s);
 851        if (state) {
 852            break;
 853        }
 854        qemu_co_queue_wait(&s->free_state_waitq, &s->mutex);
 855    }
 856
 857    if (curl_init_state(s, state) < 0) {
 858        curl_clean_state(state);
 859        acb->ret = -EIO;
 860        goto out;
 861    }
 862
 863    acb->start = 0;
 864    acb->end = MIN(acb->bytes, s->len - start);
 865
 866    state->buf_off = 0;
 867    g_free(state->orig_buf);
 868    state->buf_start = start;
 869    state->buf_len = MIN(acb->end + s->readahead_size, s->len - start);
 870    end = start + state->buf_len - 1;
 871    state->orig_buf = g_try_malloc(state->buf_len);
 872    if (state->buf_len && state->orig_buf == NULL) {
 873        curl_clean_state(state);
 874        acb->ret = -ENOMEM;
 875        goto out;
 876    }
 877    state->acb[0] = acb;
 878
 879    snprintf(state->range, 127, "%" PRIu64 "-%" PRIu64, start, end);
 880    trace_curl_setup_preadv(acb->bytes, start, state->range);
 881    curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
 882
 883    if (curl_multi_add_handle(s->multi, state->curl) != CURLM_OK) {
 884        state->acb[0] = NULL;
 885        acb->ret = -EIO;
 886
 887        curl_clean_state(state);
 888        goto out;
 889    }
 890
 891    /* Tell curl it needs to kick things off */
 892    curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 893
 894out:
 895    qemu_mutex_unlock(&s->mutex);
 896}
 897
 898static int coroutine_fn curl_co_preadv(BlockDriverState *bs,
 899        uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 900{
 901    CURLAIOCB acb = {
 902        .co = qemu_coroutine_self(),
 903        .ret = -EINPROGRESS,
 904        .qiov = qiov,
 905        .offset = offset,
 906        .bytes = bytes
 907    };
 908
 909    curl_setup_preadv(bs, &acb);
 910    while (acb.ret == -EINPROGRESS) {
 911        qemu_coroutine_yield();
 912    }
 913    return acb.ret;
 914}
 915
 916static void curl_close(BlockDriverState *bs)
 917{
 918    BDRVCURLState *s = bs->opaque;
 919
 920    trace_curl_close();
 921    curl_detach_aio_context(bs);
 922    qemu_mutex_destroy(&s->mutex);
 923
 924    g_hash_table_destroy(s->sockets);
 925    g_free(s->cookie);
 926    g_free(s->url);
 927    g_free(s->username);
 928    g_free(s->proxyusername);
 929    g_free(s->proxypassword);
 930}
 931
 932static int64_t curl_getlength(BlockDriverState *bs)
 933{
 934    BDRVCURLState *s = bs->opaque;
 935    return s->len;
 936}
 937
 938static void curl_refresh_filename(BlockDriverState *bs)
 939{
 940    BDRVCURLState *s = bs->opaque;
 941
 942    /* "readahead" and "timeout" do not change the guest-visible data,
 943     * so ignore them */
 944    if (s->sslverify != CURL_BLOCK_OPT_SSLVERIFY_DEFAULT ||
 945        s->cookie || s->username || s->password || s->proxyusername ||
 946        s->proxypassword)
 947    {
 948        return;
 949    }
 950
 951    pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), s->url);
 952}
 953
 954
 955static const char *const curl_strong_runtime_opts[] = {
 956    CURL_BLOCK_OPT_URL,
 957    CURL_BLOCK_OPT_SSLVERIFY,
 958    CURL_BLOCK_OPT_COOKIE,
 959    CURL_BLOCK_OPT_COOKIE_SECRET,
 960    CURL_BLOCK_OPT_USERNAME,
 961    CURL_BLOCK_OPT_PASSWORD_SECRET,
 962    CURL_BLOCK_OPT_PROXY_USERNAME,
 963    CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
 964
 965    NULL
 966};
 967
 968static BlockDriver bdrv_http = {
 969    .format_name                = "http",
 970    .protocol_name              = "http",
 971
 972    .instance_size              = sizeof(BDRVCURLState),
 973    .bdrv_parse_filename        = curl_parse_filename,
 974    .bdrv_file_open             = curl_open,
 975    .bdrv_close                 = curl_close,
 976    .bdrv_getlength             = curl_getlength,
 977
 978    .bdrv_co_preadv             = curl_co_preadv,
 979
 980    .bdrv_detach_aio_context    = curl_detach_aio_context,
 981    .bdrv_attach_aio_context    = curl_attach_aio_context,
 982
 983    .bdrv_refresh_filename      = curl_refresh_filename,
 984    .strong_runtime_opts        = curl_strong_runtime_opts,
 985};
 986
 987static BlockDriver bdrv_https = {
 988    .format_name                = "https",
 989    .protocol_name              = "https",
 990
 991    .instance_size              = sizeof(BDRVCURLState),
 992    .bdrv_parse_filename        = curl_parse_filename,
 993    .bdrv_file_open             = curl_open,
 994    .bdrv_close                 = curl_close,
 995    .bdrv_getlength             = curl_getlength,
 996
 997    .bdrv_co_preadv             = curl_co_preadv,
 998
 999    .bdrv_detach_aio_context    = curl_detach_aio_context,
1000    .bdrv_attach_aio_context    = curl_attach_aio_context,
1001
1002    .bdrv_refresh_filename      = curl_refresh_filename,
1003    .strong_runtime_opts        = curl_strong_runtime_opts,
1004};
1005
1006static BlockDriver bdrv_ftp = {
1007    .format_name                = "ftp",
1008    .protocol_name              = "ftp",
1009
1010    .instance_size              = sizeof(BDRVCURLState),
1011    .bdrv_parse_filename        = curl_parse_filename,
1012    .bdrv_file_open             = curl_open,
1013    .bdrv_close                 = curl_close,
1014    .bdrv_getlength             = curl_getlength,
1015
1016    .bdrv_co_preadv             = curl_co_preadv,
1017
1018    .bdrv_detach_aio_context    = curl_detach_aio_context,
1019    .bdrv_attach_aio_context    = curl_attach_aio_context,
1020
1021    .bdrv_refresh_filename      = curl_refresh_filename,
1022    .strong_runtime_opts        = curl_strong_runtime_opts,
1023};
1024
1025static BlockDriver bdrv_ftps = {
1026    .format_name                = "ftps",
1027    .protocol_name              = "ftps",
1028
1029    .instance_size              = sizeof(BDRVCURLState),
1030    .bdrv_parse_filename        = curl_parse_filename,
1031    .bdrv_file_open             = curl_open,
1032    .bdrv_close                 = curl_close,
1033    .bdrv_getlength             = curl_getlength,
1034
1035    .bdrv_co_preadv             = curl_co_preadv,
1036
1037    .bdrv_detach_aio_context    = curl_detach_aio_context,
1038    .bdrv_attach_aio_context    = curl_attach_aio_context,
1039
1040    .bdrv_refresh_filename      = curl_refresh_filename,
1041    .strong_runtime_opts        = curl_strong_runtime_opts,
1042};
1043
1044static void curl_block_init(void)
1045{
1046    bdrv_register(&bdrv_http);
1047    bdrv_register(&bdrv_https);
1048    bdrv_register(&bdrv_ftp);
1049    bdrv_register(&bdrv_ftps);
1050}
1051
1052block_init(curl_block_init);
1053