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
  25 #include "qemu/osdep.h"
  26 #include "qapi/error.h"
  27 #include "qemu/error-report.h"
  28 #include "qemu/option.h"
  29 #include "block/block_int.h"
  30 #include "qapi/qmp/qdict.h"
  31 #include "qapi/qmp/qstring.h"
  32 #include "crypto/secret.h"
  33 #include <curl/curl.h>
  34 #include "qemu/cutils.h"
  35 #include "trace.h"
  36
  37 // #define DEBUG_VERBOSE
  38
  39 #if LIBCURL_VERSION_NUM >= 0x071000
  40 /* The multi interface timer callback was introduced in 7.16.0 */
  41 #define NEED_CURL_TIMER_CALLBACK
  42 #define HAVE_SOCKET_ACTION
  43 #endif
  44
  45 #ifndef HAVE_SOCKET_ACTION
  46 /* If curl_multi_socket_action isn't available, define it statically here in
  47  * terms of curl_multi_socket. Note that ev_bitmask will be ignored, which is
  48  * less efficient but still safe. */
  49 static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
  50                                             curl_socket_t sockfd,
  51                                             int ev_bitmask,
  52                                             int *running_handles)
  53 {
  54     return curl_multi_socket(multi_handle, sockfd, running_handles);
  55 }
  56 #define curl_multi_socket_action __curl_multi_socket_action
  57 #endif
  58
  59 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
  60                    CURLPROTO_FTP | CURLPROTO_FTPS)
  61
  62 #define CURL_NUM_STATES 8
  63 #define CURL_NUM_ACB    8
  64 #define READ_AHEAD_DEFAULT (256 * 1024)
  65 #define CURL_TIMEOUT_DEFAULT 5
  66 #define CURL_TIMEOUT_MAX 10000
  67
  68 #define CURL_BLOCK_OPT_URL       "url"
  69 #define CURL_BLOCK_OPT_READAHEAD "readahead"
  70 #define CURL_BLOCK_OPT_SSLVERIFY "sslverify"
  71 #define CURL_BLOCK_OPT_TIMEOUT "timeout"
  72 #define CURL_BLOCK_OPT_COOKIE    "cookie"
  73 #define CURL_BLOCK_OPT_COOKIE_SECRET "cookie-secret"
  74 #define CURL_BLOCK_OPT_USERNAME "username"
  75 #define CURL_BLOCK_OPT_PASSWORD_SECRET "password-secret"
  76 #define CURL_BLOCK_OPT_PROXY_USERNAME "proxy-username"
  77 #define CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET "proxy-password-secret"
  78
  79 struct BDRVCURLState;
  80
  81 static bool libcurl_initialized;
  82
  83 typedef struct CURLAIOCB {
  84     Coroutine *co;
  85     QEMUIOVector *qiov;
  86
  87     uint64_t offset;
  88     uint64_t bytes;
  89     int ret;
  90
  91     size_t start;
  92     size_t end;
  93 } CURLAIOCB;
  94
  95 typedef struct CURLSocket {
  96     int fd;
  97     QLIST_ENTRY(CURLSocket) next;
  98 } CURLSocket;
  99
 100 typedef struct CURLState
 101 {
 102     struct BDRVCURLState *s;
 103     CURLAIOCB *acb[CURL_NUM_ACB];
 104     CURL *curl;
 105     QLIST_HEAD(, CURLSocket) sockets;
 106     char *orig_buf;
 107     uint64_t buf_start;
 108     size_t buf_off;
 109     size_t buf_len;
 110     char range[128];
 111     char errmsg[CURL_ERROR_SIZE];
 112     char in_use;
 113 } CURLState;
 114
 115 typedef struct BDRVCURLState {
 116     CURLM *multi;
 117     QEMUTimer timer;
 118     uint64_t len;
 119     CURLState states[CURL_NUM_STATES];
 120     char *url;
 121     size_t readahead_size;
 122     bool sslverify;
 123     uint64_t timeout;
 124     char *cookie;
 125     bool accept_range;
 126     AioContext *aio_context;
 127     QemuMutex mutex;
 128     CoQueue free_state_waitq;
 129     char *username;
 130     char *password;
 131     char *proxyusername;
 132     char *proxypassword;
 133 } BDRVCURLState;
 134
 135 static void curl_clean_state(CURLState *s);
 136 static void curl_multi_do(void *arg);
 137 static void curl_multi_read(void *arg);
 138
 139 #ifdef NEED_CURL_TIMER_CALLBACK
 140 /* Called from curl_multi_do_locked, with s->mutex held.  */
 141 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
 142 {
 143     BDRVCURLState *s = opaque;
 144
 145     trace_curl_timer_cb(timeout_ms);
 146     if (timeout_ms == -1) {
 147         timer_del(&s->timer);
 148     } else {
 149         int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
 150         timer_mod(&s->timer,
 151                   qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
 152     }
 153     return 0;
 154 }
 155 #endif
 156
 157 /* Called from curl_multi_do_locked, with s->mutex held.  */
 158 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
 159                         void *userp, void *sp)
 160 {
 161     BDRVCURLState *s;
 162     CURLState *state = NULL;
 163     CURLSocket *socket;
 164
 165     curl_easy_getinfo(curl, CURLINFO_PRIVATE, (char **)&state);
 166     s = state->s;
 167
 168     QLIST_FOREACH(socket, &state->sockets, next) {
 169         if (socket->fd == fd) {
 170             if (action == CURL_POLL_REMOVE) {
 171                 QLIST_REMOVE(socket, next);
 172                 g_free(socket);
 173             }
 174             break;
 175         }
 176     }
 177     if (!socket) {
 178         socket = g_new0(CURLSocket, 1);
 179         socket->fd = fd;
 180         QLIST_INSERT_HEAD(&state->sockets, socket, next);
 181     }
 182     socket = NULL;
 183
 184     trace_curl_sock_cb(action, (int)fd);
 185     switch (action) {
 186         case CURL_POLL_IN:
 187             aio_set_fd_handler(s->aio_context, fd, false,
 188                                curl_multi_read, NULL, NULL, state);
 189             break;
 190         case CURL_POLL_OUT:
 191             aio_set_fd_handler(s->aio_context, fd, false,
 192                                NULL, curl_multi_do, NULL, state);
 193             break;
 194         case CURL_POLL_INOUT:
 195             aio_set_fd_handler(s->aio_context, fd, false,
 196                                curl_multi_read, curl_multi_do, NULL, state);
 197             break;
 198         case CURL_POLL_REMOVE:
 199             aio_set_fd_handler(s->aio_context, fd, false,
 200                                NULL, NULL, NULL, NULL);
 201             break;
 202     }
 203
 204     return 0;
 205 }
 206
 207 /* Called from curl_multi_do_locked, with s->mutex held.  */
 208 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 209 {
 210     BDRVCURLState *s = opaque;
 211     size_t realsize = size * nmemb;
 212     const char *accept_line = "Accept-Ranges: bytes";
 213
 214     if (realsize >= strlen(accept_line)
 215         && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
 216         s->accept_range = true;
 217     }
 218
 219     return realsize;
 220 }
 221
 222 /* Called from curl_multi_do_locked, with s->mutex held.  */
 223 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
 224 {
 225     CURLState *s = ((CURLState*)opaque);
 226     size_t realsize = size * nmemb;
 227     int i;
 228
 229     trace_curl_read_cb(realsize);
 230
 231     if (!s || !s->orig_buf) {
 232         goto read_end;
 233     }
 234
 235     if (s->buf_off >= s->buf_len) {
 236         /* buffer full, read nothing */
 237         goto read_end;
 238     }
 239     realsize = MIN(realsize, s->buf_len - s->buf_off);
 240     memcpy(s->orig_buf + s->buf_off, ptr, realsize);
 241     s->buf_off += realsize;
 242
 243     for(i=0; i<CURL_NUM_ACB; i++) {
 244         CURLAIOCB *acb = s->acb[i];
 245
 246         if (!acb)
 247             continue;
 248
 249         if ((s->buf_off >= acb->end)) {
 250             size_t request_length = acb->bytes;
 251
 252             qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
 253                                 acb->end - acb->start);
 254
 255             if (acb->end - acb->start < request_length) {
 256                 size_t offset = acb->end - acb->start;
 257                 qemu_iovec_memset(acb->qiov, offset, 0,
 258                                   request_length - offset);
 259             }
 260
 261             acb->ret = 0;
 262             s->acb[i] = NULL;
 263             qemu_mutex_unlock(&s->s->mutex);
 264             aio_co_wake(acb->co);
 265             qemu_mutex_lock(&s->s->mutex);
 266         }
 267     }
 268
 269 read_end:
 270     /* curl will error out if we do not return this value */
 271     return size * nmemb;
 272 }
 273
 274 /* Called with s->mutex held.  */
 275 static bool curl_find_buf(BDRVCURLState *s, uint64_t start, uint64_t len,
 276                           CURLAIOCB *acb)
 277 {
 278     int i;
 279     uint64_t end = start + len;
 280     uint64_t clamped_end = MIN(end, s->len);
 281     uint64_t clamped_len = clamped_end - start;
 282
 283     for (i=0; i<CURL_NUM_STATES; i++) {
 284         CURLState *state = &s->states[i];
 285         uint64_t buf_end = (state->buf_start + state->buf_off);
 286         uint64_t buf_fend = (state->buf_start + state->buf_len);
 287
 288         if (!state->orig_buf)
 289             continue;
 290         if (!state->buf_off)
 291             continue;
 292
 293         // Does the existing buffer cover our section?
 294         if ((start >= state->buf_start) &&
 295             (start <= buf_end) &&
 296             (clamped_end >= state->buf_start) &&
 297             (clamped_end <= buf_end))
 298         {
 299             char *buf = state->orig_buf + (start - state->buf_start);
 300
 301             qemu_iovec_from_buf(acb->qiov, 0, buf, clamped_len);
 302             if (clamped_len < len) {
 303                 qemu_iovec_memset(acb->qiov, clamped_len, 0, len - clamped_len);
 304             }
 305             acb->ret = 0;
 306             return true;
 307         }
 308
 309         // Wait for unfinished chunks
 310         if (state->in_use &&
 311             (start >= state->buf_start) &&
 312             (start <= buf_fend) &&
 313             (clamped_end >= state->buf_start) &&
 314             (clamped_end <= buf_fend))
 315         {
 316             int j;
 317
 318             acb->start = start - state->buf_start;
 319             acb->end = acb->start + clamped_len;
 320
 321             for (j=0; j<CURL_NUM_ACB; j++) {
 322                 if (!state->acb[j]) {
 323                     state->acb[j] = acb;
 324                     return true;
 325                 }
 326             }
 327         }
 328     }
 329
 330     return false;
 331 }
 332
 333 /* Called with s->mutex held.  */
 334 static void curl_multi_check_completion(BDRVCURLState *s)
 335 {
 336     int msgs_in_queue;
 337
 338     /* Try to find done transfers, so we can free the easy
 339      * handle again. */
 340     for (;;) {
 341         CURLMsg *msg;
 342         msg = curl_multi_info_read(s->multi, &msgs_in_queue);
 343
 344         /* Quit when there are no more completions */
 345         if (!msg)
 346             break;
 347
 348         if (msg->msg == CURLMSG_DONE) {
 349             CURLState *state = NULL;
 350             curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
 351                               (char **)&state);
 352
 353             /* ACBs for successful messages get completed in curl_read_cb */
 354             if (msg->data.result != CURLE_OK) {
 355                 int i;
 356                 static int errcount = 100;
 357
 358                 /* Don't lose the original error message from curl, since
 359                  * it contains extra data.
 360                  */
 361                 if (errcount > 0) {
 362                     error_report("curl: %s", state->errmsg);
 363                     if (--errcount == 0) {
 364                         error_report("curl: further errors suppressed");
 365                     }
 366                 }
 367
 368                 for (i = 0; i < CURL_NUM_ACB; i++) {
 369                     CURLAIOCB *acb = state->acb[i];
 370
 371                     if (acb == NULL) {
 372                         continue;
 373                     }
 374
 375                     acb->ret = -EIO;
 376                     state->acb[i] = NULL;
 377                     qemu_mutex_unlock(&s->mutex);
 378                     aio_co_wake(acb->co);
 379                     qemu_mutex_lock(&s->mutex);
 380                 }
 381             }
 382
 383             curl_clean_state(state);
 384             break;
 385         }
 386     }
 387 }
 388
 389 /* Called with s->mutex held.  */
 390 static void curl_multi_do_locked(CURLState *s)
 391 {
 392     CURLSocket *socket, *next_socket;
 393     int running;
 394     int r;
 395
 396     if (!s->s->multi) {
 397         return;
 398     }
 399
 400     /* Need to use _SAFE because curl_multi_socket_action() may trigger
 401      * curl_sock_cb() which might modify this list */
 402     QLIST_FOREACH_SAFE(socket, &s->sockets, next, next_socket) {
 403         do {
 404             r = curl_multi_socket_action(s->s->multi, socket->fd, 0, &running);
 405         } while (r == CURLM_CALL_MULTI_PERFORM);
 406     }
 407 }
 408
 409 static void curl_multi_do(void *arg)
 410 {
 411     CURLState *s = (CURLState *)arg;
 412
 413     qemu_mutex_lock(&s->s->mutex);
 414     curl_multi_do_locked(s);
 415     qemu_mutex_unlock(&s->s->mutex);
 416 }
 417
 418 static void curl_multi_read(void *arg)
 419 {
 420     CURLState *s = (CURLState *)arg;
 421
 422     qemu_mutex_lock(&s->s->mutex);
 423     curl_multi_do_locked(s);
 424     curl_multi_check_completion(s->s);
 425     qemu_mutex_unlock(&s->s->mutex);
 426 }
 427
 428 static void curl_multi_timeout_do(void *arg)
 429 {
 430 #ifdef NEED_CURL_TIMER_CALLBACK
 431     BDRVCURLState *s = (BDRVCURLState *)arg;
 432     int running;
 433
 434     if (!s->multi) {
 435         return;
 436     }
 437
 438     qemu_mutex_lock(&s->mutex);
 439     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 440
 441     curl_multi_check_completion(s);
 442     qemu_mutex_unlock(&s->mutex);
 443 #else
 444     abort();
 445 #endif
 446 }
 447
 448 /* Called with s->mutex held.  */
 449 static CURLState *curl_find_state(BDRVCURLState *s)
 450 {
 451     CURLState *state = NULL;
 452     int i;
 453
 454     for (i = 0; i < CURL_NUM_STATES; i++) {
 455         if (!s->states[i].in_use) {
 456             state = &s->states[i];
 457             state->in_use = 1;
 458             break;
 459         }
 460     }
 461     return state;
 462 }
 463
 464 static int curl_init_state(BDRVCURLState *s, CURLState *state)
 465 {
 466     if (!state->curl) {
 467         state->curl = curl_easy_init();
 468         if (!state->curl) {
 469             return -EIO;
 470         }
 471         curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
 472         curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYPEER,
 473                          (long) s->sslverify);
 474         curl_easy_setopt(state->curl, CURLOPT_SSL_VERIFYHOST,
 475                          s->sslverify ? 2L : 0L);
 476         if (s->cookie) {
 477             curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
 478         }
 479         curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
 480         curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
 481                          (void *)curl_read_cb);
 482         curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
 483         curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
 484         curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
 485         curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
 486         curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
 487         curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
 488         curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
 489
 490         if (s->username) {
 491             curl_easy_setopt(state->curl, CURLOPT_USERNAME, s->username);
 492         }
 493         if (s->password) {
 494             curl_easy_setopt(state->curl, CURLOPT_PASSWORD, s->password);
 495         }
 496         if (s->proxyusername) {
 497             curl_easy_setopt(state->curl,
 498                              CURLOPT_PROXYUSERNAME, s->proxyusername);
 499         }
 500         if (s->proxypassword) {
 501             curl_easy_setopt(state->curl,
 502                              CURLOPT_PROXYPASSWORD, s->proxypassword);
 503         }
 504
 505         /* Restrict supported protocols to avoid security issues in the more
 506          * obscure protocols.  For example, do not allow POP3/SMTP/IMAP see
 507          * CVE-2013-0249.
 508          *
 509          * Restricting protocols is only supported from 7.19.4 upwards.
 510          */
 511 #if LIBCURL_VERSION_NUM >= 0x071304
 512         curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
 513         curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
 514 #endif
 515
 516 #ifdef DEBUG_VERBOSE
 517         curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
 518 #endif
 519     }
 520
 521     QLIST_INIT(&state->sockets);
 522     state->s = s;
 523
 524     return 0;
 525 }
 526
 527 /* Called with s->mutex held.  */
 528 static void curl_clean_state(CURLState *s)
 529 {
 530     int j;
 531     for (j = 0; j < CURL_NUM_ACB; j++) {
 532         assert(!s->acb[j]);
 533     }
 534
 535     if (s->s->multi)
 536         curl_multi_remove_handle(s->s->multi, s->curl);
 537
 538     while (!QLIST_EMPTY(&s->sockets)) {
 539         CURLSocket *socket = QLIST_FIRST(&s->sockets);
 540
 541         QLIST_REMOVE(socket, next);
 542         g_free(socket);
 543     }
 544
 545     s->in_use = 0;
 546
 547     qemu_co_enter_next(&s->s->free_state_waitq, &s->s->mutex);
 548 }
 549
 550 static void curl_parse_filename(const char *filename, QDict *options,
 551                                 Error **errp)
 552 {
 553     qdict_put_str(options, CURL_BLOCK_OPT_URL, filename);
 554 }
 555
 556 static void curl_detach_aio_context(BlockDriverState *bs)
 557 {
 558     BDRVCURLState *s = bs->opaque;
 559     int i;
 560
 561     qemu_mutex_lock(&s->mutex);
 562     for (i = 0; i < CURL_NUM_STATES; i++) {
 563         if (s->states[i].in_use) {
 564             curl_clean_state(&s->states[i]);
 565         }
 566         if (s->states[i].curl) {
 567             curl_easy_cleanup(s->states[i].curl);
 568             s->states[i].curl = NULL;
 569         }
 570         g_free(s->states[i].orig_buf);
 571         s->states[i].orig_buf = NULL;
 572     }
 573     if (s->multi) {
 574         curl_multi_cleanup(s->multi);
 575         s->multi = NULL;
 576     }
 577     qemu_mutex_unlock(&s->mutex);
 578
 579     timer_del(&s->timer);
 580 }
 581
 582 static void curl_attach_aio_context(BlockDriverState *bs,
 583                                     AioContext *new_context)
 584 {
 585     BDRVCURLState *s = bs->opaque;
 586
 587     aio_timer_init(new_context, &s->timer,
 588                    QEMU_CLOCK_REALTIME, SCALE_NS,
 589                    curl_multi_timeout_do, s);
 590
 591     assert(!s->multi);
 592     s->multi = curl_multi_init();
 593     s->aio_context = new_context;
 594     curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
 595 #ifdef NEED_CURL_TIMER_CALLBACK
 596     curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
 597     curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
 598 #endif
 599 }
 600
 601 static QemuOptsList runtime_opts = {
 602     .name = "curl",
 603     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
 604     .desc = {
 605         {
 606             .name = CURL_BLOCK_OPT_URL,
 607             .type = QEMU_OPT_STRING,
 608             .help = "URL to open",
 609         },
 610         {
 611             .name = CURL_BLOCK_OPT_READAHEAD,
 612             .type = QEMU_OPT_SIZE,
 613             .help = "Readahead size",
 614         },
 615         {
 616             .name = CURL_BLOCK_OPT_SSLVERIFY,
 617             .type = QEMU_OPT_BOOL,
 618             .help = "Verify SSL certificate"
 619         },
 620         {
 621             .name = CURL_BLOCK_OPT_TIMEOUT,
 622             .type = QEMU_OPT_NUMBER,
 623             .help = "Curl timeout"
 624         },
 625         {
 626             .name = CURL_BLOCK_OPT_COOKIE,
 627             .type = QEMU_OPT_STRING,
 628             .help = "Pass the cookie or list of cookies with each request"
 629         },
 630         {
 631             .name = CURL_BLOCK_OPT_COOKIE_SECRET,
 632             .type = QEMU_OPT_STRING,
 633             .help = "ID of secret used as cookie passed with each request"
 634         },
 635         {
 636             .name = CURL_BLOCK_OPT_USERNAME,
 637             .type = QEMU_OPT_STRING,
 638             .help = "Username for HTTP auth"
 639         },
 640         {
 641             .name = CURL_BLOCK_OPT_PASSWORD_SECRET,
 642             .type = QEMU_OPT_STRING,
 643             .help = "ID of secret used as password for HTTP auth",
 644         },
 645         {
 646             .name = CURL_BLOCK_OPT_PROXY_USERNAME,
 647             .type = QEMU_OPT_STRING,
 648             .help = "Username for HTTP proxy auth"
 649         },
 650         {
 651             .name = CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET,
 652             .type = QEMU_OPT_STRING,
 653             .help = "ID of secret used as password for HTTP proxy auth",
 654         },
 655         { /* end of list */ }
 656     },
 657 };
 658
 659
 660 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
 661                      Error **errp)
 662 {
 663     BDRVCURLState *s = bs->opaque;
 664     CURLState *state = NULL;
 665     QemuOpts *opts;
 666     Error *local_err = NULL;
 667     const char *file;
 668     const char *cookie;
 669     const char *cookie_secret;
 670     double d;
 671     const char *secretid;
 672     const char *protocol_delimiter;
 673     int ret;
 674
 675     ret = bdrv_apply_auto_read_only(bs, "curl driver does not support writes",
 676                                     errp);
 677     if (ret < 0) {
 678         return ret;
 679     }
 680
 681     if (!libcurl_initialized) {
 682         ret = curl_global_init(CURL_GLOBAL_ALL);
 683         if (ret) {
 684             error_setg(errp, "libcurl initialization failed with %d", ret);
 685             return -EIO;
 686         }
 687         libcurl_initialized = true;
 688     }
 689
 690     qemu_mutex_init(&s->mutex);
 691     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
 692     qemu_opts_absorb_qdict(opts, options, &local_err);
 693     if (local_err) {
 694         error_propagate(errp, local_err);
 695         goto out_noclean;
 696     }
 697
 698     s->readahead_size = qemu_opt_get_size(opts, CURL_BLOCK_OPT_READAHEAD,
 699                                           READ_AHEAD_DEFAULT);
 700     if ((s->readahead_size & 0x1ff) != 0) {
 701         error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
 702                    s->readahead_size);
 703         goto out_noclean;
 704     }
 705
 706     s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
 707                                      CURL_TIMEOUT_DEFAULT);
 708     if (s->timeout > CURL_TIMEOUT_MAX) {
 709         error_setg(errp, "timeout parameter is too large or negative");
 710         goto out_noclean;
 711     }
 712
 713     s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
 714
 715     cookie = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE);
 716     cookie_secret = qemu_opt_get(opts, CURL_BLOCK_OPT_COOKIE_SECRET);
 717
 718     if (cookie && cookie_secret) {
 719         error_setg(errp,
 720                    "curl driver cannot handle both cookie and cookie secret");
 721         goto out_noclean;
 722     }
 723
 724     if (cookie_secret) {
 725         s->cookie = qcrypto_secret_lookup_as_utf8(cookie_secret, errp);
 726         if (!s->cookie) {
 727             goto out_noclean;
 728         }
 729     } else {
 730         s->cookie = g_strdup(cookie);
 731     }
 732
 733     file = qemu_opt_get(opts, CURL_BLOCK_OPT_URL);
 734     if (file == NULL) {
 735         error_setg(errp, "curl block driver requires an 'url' option");
 736         goto out_noclean;
 737     }
 738
 739     if (!strstart(file, bs->drv->protocol_name, &protocol_delimiter) ||
 740         !strstart(protocol_delimiter, "://", NULL))
 741     {
 742         error_setg(errp, "%s curl driver cannot handle the URL '%s' (does not "
 743                    "start with '%s://')", bs->drv->protocol_name, file,
 744                    bs->drv->protocol_name);
 745         goto out_noclean;
 746     }
 747
 748     s->username = g_strdup(qemu_opt_get(opts, CURL_BLOCK_OPT_USERNAME));
 749     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PASSWORD_SECRET);
 750
 751     if (secretid) {
 752         s->password = qcrypto_secret_lookup_as_utf8(secretid, errp);
 753         if (!s->password) {
 754             goto out_noclean;
 755         }
 756     }
 757
 758     s->proxyusername = g_strdup(
 759         qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_USERNAME));
 760     secretid = qemu_opt_get(opts, CURL_BLOCK_OPT_PROXY_PASSWORD_SECRET);
 761     if (secretid) {
 762         s->proxypassword = qcrypto_secret_lookup_as_utf8(secretid, errp);
 763         if (!s->proxypassword) {
 764             goto out_noclean;
 765         }
 766     }
 767
 768     trace_curl_open(file);
 769     qemu_co_queue_init(&s->free_state_waitq);
 770     s->aio_context = bdrv_get_aio_context(bs);
 771     s->url = g_strdup(file);
 772     qemu_mutex_lock(&s->mutex);
 773     state = curl_find_state(s);
 774     qemu_mutex_unlock(&s->mutex);
 775     if (!state) {
 776         goto out_noclean;
 777     }
 778
 779     // Get file size
 780
 781     if (curl_init_state(s, state) < 0) {
 782         goto out;
 783     }
 784
 785     s->accept_range = false;
 786     curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
 787     curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
 788                      curl_header_cb);
 789     curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
 790     if (curl_easy_perform(state->curl))
 791         goto out;
 792     if (curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d)) {
 793         goto out;
 794     }
 795     /* Prior CURL 7.19.4 return value of 0 could mean that the file size is not
 796      * know or the size is zero. From 7.19.4 CURL returns -1 if size is not
 797      * known and zero if it is really zero-length file. */
 798 #if LIBCURL_VERSION_NUM >= 0x071304
 799     if (d < 0) {
 800         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 801                 "Server didn't report file size.");
 802         goto out;
 803     }
 804 #else
 805     if (d <= 0) {
 806         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 807                 "Unknown file size or zero-length file.");
 808         goto out;
 809     }
 810 #endif
 811
 812     s->len = d;
 813
 814     if ((!strncasecmp(s->url, "http://", strlen("http://"))
 815         || !strncasecmp(s->url, "https://", strlen("https://")))
 816         && !s->accept_range) {
 817         pstrcpy(state->errmsg, CURL_ERROR_SIZE,
 818                 "Server does not support 'range' (byte ranges).");
 819         goto out;
 820     }
 821     trace_curl_open_size(s->len);
 822
 823     qemu_mutex_lock(&s->mutex);
 824     curl_clean_state(state);
 825     qemu_mutex_unlock(&s->mutex);
 826     curl_easy_cleanup(state->curl);
 827     state->curl = NULL;
 828
 829     curl_attach_aio_context(bs, bdrv_get_aio_context(bs));
 830
 831     qemu_opts_del(opts);
 832     return 0;
 833
 834 out:
 835     error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
 836     curl_easy_cleanup(state->curl);
 837     state->curl = NULL;
 838 out_noclean:
 839     qemu_mutex_destroy(&s->mutex);
 840     g_free(s->cookie);
 841     g_free(s->url);
 842     g_free(s->username);
 843     g_free(s->proxyusername);
 844     g_free(s->proxypassword);
 845     qemu_opts_del(opts);
 846     return -EINVAL;
 847 }
 848
 849 static void curl_setup_preadv(BlockDriverState *bs, CURLAIOCB *acb)
 850 {
 851     CURLState *state;
 852     int running;
 853
 854     BDRVCURLState *s = bs->opaque;
 855
 856     uint64_t start = acb->offset;
 857     uint64_t end;
 858
 859     qemu_mutex_lock(&s->mutex);
 860
 861     // In case we have the requested data already (e.g. read-ahead),
 862     // we can just call the callback and be done.
 863     if (curl_find_buf(s, start, acb->bytes, acb)) {
 864         goto out;
 865     }
 866
 867     // No cache found, so let's start a new request
 868     for (;;) {
 869         state = curl_find_state(s);
 870         if (state) {
 871             break;
 872         }
 873         qemu_co_queue_wait(&s->free_state_waitq, &s->mutex);
 874     }
 875
 876     if (curl_init_state(s, state) < 0) {
 877         curl_clean_state(state);
 878         acb->ret = -EIO;
 879         goto out;
 880     }
 881
 882     acb->start = 0;
 883     acb->end = MIN(acb->bytes, s->len - start);
 884
 885     state->buf_off = 0;
 886     g_free(state->orig_buf);
 887     state->buf_start = start;
 888     state->buf_len = MIN(acb->end + s->readahead_size, s->len - start);
 889     end = start + state->buf_len - 1;
 890     state->orig_buf = g_try_malloc(state->buf_len);
 891     if (state->buf_len && state->orig_buf == NULL) {
 892         curl_clean_state(state);
 893         acb->ret = -ENOMEM;
 894         goto out;
 895     }
 896     state->acb[0] = acb;
 897
 898     snprintf(state->range, 127, "%" PRIu64 "-%" PRIu64, start, end);
 899     trace_curl_setup_preadv(acb->bytes, start, state->range);
 900     curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
 901
 902     curl_multi_add_handle(s->multi, state->curl);
 903
 904     /* Tell curl it needs to kick things off */
 905     curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
 906
 907 out:
 908     qemu_mutex_unlock(&s->mutex);
 909 }
 910
 911 static int coroutine_fn curl_co_preadv(BlockDriverState *bs,
 912         uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
 913 {
 914     CURLAIOCB acb = {
 915         .co = qemu_coroutine_self(),
 916         .ret = -EINPROGRESS,
 917         .qiov = qiov,
 918         .offset = offset,
 919         .bytes = bytes
 920     };
 921
 922     curl_setup_preadv(bs, &acb);
 923     while (acb.ret == -EINPROGRESS) {
 924         qemu_coroutine_yield();
 925     }
 926     return acb.ret;
 927 }
 928
 929 static void curl_close(BlockDriverState *bs)
 930 {
 931     BDRVCURLState *s = bs->opaque;
 932
 933     trace_curl_close();
 934     curl_detach_aio_context(bs);
 935     qemu_mutex_destroy(&s->mutex);
 936
 937     g_free(s->cookie);
 938     g_free(s->url);
 939     g_free(s->username);
 940     g_free(s->proxyusername);
 941     g_free(s->proxypassword);
 942 }
 943
 944 static int64_t curl_getlength(BlockDriverState *bs)
 945 {
 946     BDRVCURLState *s = bs->opaque;
 947     return s->len;
 948 }
 949
 950 static BlockDriver bdrv_http = {
 951     .format_name                = "http",
 952     .protocol_name              = "http",
 953
 954     .instance_size              = sizeof(BDRVCURLState),
 955     .bdrv_parse_filename        = curl_parse_filename,
 956     .bdrv_file_open             = curl_open,
 957     .bdrv_close                 = curl_close,
 958     .bdrv_getlength             = curl_getlength,
 959
 960     .bdrv_co_preadv             = curl_co_preadv,
 961
 962     .bdrv_detach_aio_context    = curl_detach_aio_context,
 963     .bdrv_attach_aio_context    = curl_attach_aio_context,
 964 };
 965
 966 static BlockDriver bdrv_https = {
 967     .format_name                = "https",
 968     .protocol_name              = "https",
 969
 970     .instance_size              = sizeof(BDRVCURLState),
 971     .bdrv_parse_filename        = curl_parse_filename,
 972     .bdrv_file_open             = curl_open,
 973     .bdrv_close                 = curl_close,
 974     .bdrv_getlength             = curl_getlength,
 975
 976     .bdrv_co_preadv             = curl_co_preadv,
 977
 978     .bdrv_detach_aio_context    = curl_detach_aio_context,
 979     .bdrv_attach_aio_context    = curl_attach_aio_context,
 980 };
 981
 982 static BlockDriver bdrv_ftp = {
 983     .format_name                = "ftp",
 984     .protocol_name              = "ftp",
 985
 986     .instance_size              = sizeof(BDRVCURLState),
 987     .bdrv_parse_filename        = curl_parse_filename,
 988     .bdrv_file_open             = curl_open,
 989     .bdrv_close                 = curl_close,
 990     .bdrv_getlength             = curl_getlength,
 991
 992     .bdrv_co_preadv             = curl_co_preadv,
 993
 994     .bdrv_detach_aio_context    = curl_detach_aio_context,
 995     .bdrv_attach_aio_context    = curl_attach_aio_context,
 996 };
 997
 998 static BlockDriver bdrv_ftps = {
 999     .format_name                = "ftps",
1000     .protocol_name              = "ftps",
1001
1002     .instance_size              = sizeof(BDRVCURLState),
1003     .bdrv_parse_filename        = curl_parse_filename,
1004     .bdrv_file_open             = curl_open,
1005     .bdrv_close                 = curl_close,
1006     .bdrv_getlength             = curl_getlength,
1007
1008     .bdrv_co_preadv             = curl_co_preadv,
1009
1010     .bdrv_detach_aio_context    = curl_detach_aio_context,
1011     .bdrv_attach_aio_context    = curl_attach_aio_context,
1012 };
1013
1014 static void curl_block_init(void)
1015 {
1016     bdrv_register(&bdrv_http);
1017     bdrv_register(&bdrv_https);
1018     bdrv_register(&bdrv_ftp);
1019     bdrv_register(&bdrv_ftps);
1020 }
1021
1022 block_init(curl_block_init);