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