git.oblomov.eu Git - git/blob - http.c

   1 #include "git-compat-util.h"
   2 #include "http.h"
   3 #include "pack.h"
   4 #include "sideband.h"
   5 #include "run-command.h"
   6 #include "url.h"
   7 #include "urlmatch.h"
   8 #include "credential.h"
   9 #include "version.h"
  10 #include "pkt-line.h"
  11 #include "gettext.h"
  12 #include "transport.h"
  13
  14 int active_requests;
  15 int http_is_verbose;
  16 size_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  17
  18 #if LIBCURL_VERSION_NUM >= 0x070a06
  19 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  20 #endif
  21
  22 static int min_curl_sessions = 1;
  23 static int curl_session_count;
  24 #ifdef USE_CURL_MULTI
  25 static int max_requests = -1;
  26 static CURLM *curlm;
  27 #endif
  28 #ifndef NO_CURL_EASY_DUPHANDLE
  29 static CURL *curl_default;
  30 #endif
  31
  32 #define PREV_BUF_SIZE 4096
  33 #define RANGE_HEADER_SIZE 30
  34
  35 char curl_errorstr[CURL_ERROR_SIZE];
  36
  37 static int curl_ssl_verify = -1;
  38 static int curl_ssl_try;
  39 static const char *ssl_cert;
  40 static const char *ssl_cipherlist;
  41 static const char *ssl_version;
  42 static struct {
  43         const char *name;
  44         long ssl_version;
  45 } sslversions[] = {
  46         { "sslv2", CURL_SSLVERSION_SSLv2 },
  47         { "sslv3", CURL_SSLVERSION_SSLv3 },
  48         { "tlsv1", CURL_SSLVERSION_TLSv1 },
  49 #if LIBCURL_VERSION_NUM >= 0x072200
  50         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
  51         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  52         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  53 #endif
  54 };
  55 #if LIBCURL_VERSION_NUM >= 0x070903
  56 static const char *ssl_key;
  57 #endif
  58 #if LIBCURL_VERSION_NUM >= 0x070908
  59 static const char *ssl_capath;
  60 #endif
  61 static const char *ssl_cainfo;
  62 static long curl_low_speed_limit = -1;
  63 static long curl_low_speed_time = -1;
  64 static int curl_ftp_no_epsv;
  65 static const char *curl_http_proxy;
  66 static const char *curl_cookie_file;
  67 static int curl_save_cookies;
  68 struct credential http_auth = CREDENTIAL_INIT;
  69 static int http_proactive_auth;
  70 static const char *user_agent;
  71
  72 #if LIBCURL_VERSION_NUM >= 0x071700
  73 /* Use CURLOPT_KEYPASSWD as is */
  74 #elif LIBCURL_VERSION_NUM >= 0x070903
  75 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  76 #else
  77 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  78 #endif
  79
  80 static struct credential cert_auth = CREDENTIAL_INIT;
  81 static int ssl_cert_password_required;
  82 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  83 static unsigned long http_auth_methods = CURLAUTH_ANY;
  84 #endif
  85
  86 static struct curl_slist *pragma_header;
  87 static struct curl_slist *no_pragma_header;
  88
  89 static struct active_request_slot *active_queue_head;
  90
  91 static char *cached_accept_language;
  92
  93 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  94 {
  95         size_t size = eltsize * nmemb;
  96         struct buffer *buffer = buffer_;
  97
  98         if (size > buffer->buf.len - buffer->posn)
  99                 size = buffer->buf.len - buffer->posn;
 100         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 101         buffer->posn += size;
 102
 103         return size;
 104 }
 105
 106 #ifndef NO_CURL_IOCTL
 107 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 108 {
 109         struct buffer *buffer = clientp;
 110
 111         switch (cmd) {
 112         case CURLIOCMD_NOP:
 113                 return CURLIOE_OK;
 114
 115         case CURLIOCMD_RESTARTREAD:
 116                 buffer->posn = 0;
 117                 return CURLIOE_OK;
 118
 119         default:
 120                 return CURLIOE_UNKNOWNCMD;
 121         }
 122 }
 123 #endif
 124
 125 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 126 {
 127         size_t size = eltsize * nmemb;
 128         struct strbuf *buffer = buffer_;
 129
 130         strbuf_add(buffer, ptr, size);
 131         return size;
 132 }
 133
 134 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 135 {
 136         return eltsize * nmemb;
 137 }
 138
 139 static void closedown_active_slot(struct active_request_slot *slot)
 140 {
 141         active_requests--;
 142         slot->in_use = 0;
 143 }
 144
 145 static void finish_active_slot(struct active_request_slot *slot)
 146 {
 147         closedown_active_slot(slot);
 148         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 149
 150         if (slot->finished != NULL)
 151                 (*slot->finished) = 1;
 152
 153         /* Store slot results so they can be read after the slot is reused */
 154         if (slot->results != NULL) {
 155                 slot->results->curl_result = slot->curl_result;
 156                 slot->results->http_code = slot->http_code;
 157 #if LIBCURL_VERSION_NUM >= 0x070a08
 158                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 159                                   &slot->results->auth_avail);
 160 #else
 161                 slot->results->auth_avail = 0;
 162 #endif
 163         }
 164
 165         /* Run callback if appropriate */
 166         if (slot->callback_func != NULL)
 167                 slot->callback_func(slot->callback_data);
 168 }
 169
 170 #ifdef USE_CURL_MULTI
 171 static void process_curl_messages(void)
 172 {
 173         int num_messages;
 174         struct active_request_slot *slot;
 175         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 176
 177         while (curl_message != NULL) {
 178                 if (curl_message->msg == CURLMSG_DONE) {
 179                         int curl_result = curl_message->data.result;
 180                         slot = active_queue_head;
 181                         while (slot != NULL &&
 182                                slot->curl != curl_message->easy_handle)
 183                                 slot = slot->next;
 184                         if (slot != NULL) {
 185                                 curl_multi_remove_handle(curlm, slot->curl);
 186                                 slot->curl_result = curl_result;
 187                                 finish_active_slot(slot);
 188                         } else {
 189                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 190                         }
 191                 } else {
 192                         fprintf(stderr, "Unknown CURL message received: %d\n",
 193                                 (int)curl_message->msg);
 194                 }
 195                 curl_message = curl_multi_info_read(curlm, &num_messages);
 196         }
 197 }
 198 #endif
 199
 200 static int http_options(const char *var, const char *value, void *cb)
 201 {
 202         if (!strcmp("http.sslverify", var)) {
 203                 curl_ssl_verify = git_config_bool(var, value);
 204                 return 0;
 205         }
 206         if (!strcmp("http.sslcipherlist", var))
 207                 return git_config_string(&ssl_cipherlist, var, value);
 208         if (!strcmp("http.sslversion", var))
 209                 return git_config_string(&ssl_version, var, value);
 210         if (!strcmp("http.sslcert", var))
 211                 return git_config_string(&ssl_cert, var, value);
 212 #if LIBCURL_VERSION_NUM >= 0x070903
 213         if (!strcmp("http.sslkey", var))
 214                 return git_config_string(&ssl_key, var, value);
 215 #endif
 216 #if LIBCURL_VERSION_NUM >= 0x070908
 217         if (!strcmp("http.sslcapath", var))
 218                 return git_config_string(&ssl_capath, var, value);
 219 #endif
 220         if (!strcmp("http.sslcainfo", var))
 221                 return git_config_string(&ssl_cainfo, var, value);
 222         if (!strcmp("http.sslcertpasswordprotected", var)) {
 223                 ssl_cert_password_required = git_config_bool(var, value);
 224                 return 0;
 225         }
 226         if (!strcmp("http.ssltry", var)) {
 227                 curl_ssl_try = git_config_bool(var, value);
 228                 return 0;
 229         }
 230         if (!strcmp("http.minsessions", var)) {
 231                 min_curl_sessions = git_config_int(var, value);
 232 #ifndef USE_CURL_MULTI
 233                 if (min_curl_sessions > 1)
 234                         min_curl_sessions = 1;
 235 #endif
 236                 return 0;
 237         }
 238 #ifdef USE_CURL_MULTI
 239         if (!strcmp("http.maxrequests", var)) {
 240                 max_requests = git_config_int(var, value);
 241                 return 0;
 242         }
 243 #endif
 244         if (!strcmp("http.lowspeedlimit", var)) {
 245                 curl_low_speed_limit = (long)git_config_int(var, value);
 246                 return 0;
 247         }
 248         if (!strcmp("http.lowspeedtime", var)) {
 249                 curl_low_speed_time = (long)git_config_int(var, value);
 250                 return 0;
 251         }
 252
 253         if (!strcmp("http.noepsv", var)) {
 254                 curl_ftp_no_epsv = git_config_bool(var, value);
 255                 return 0;
 256         }
 257         if (!strcmp("http.proxy", var))
 258                 return git_config_string(&curl_http_proxy, var, value);
 259
 260         if (!strcmp("http.cookiefile", var))
 261                 return git_config_string(&curl_cookie_file, var, value);
 262         if (!strcmp("http.savecookies", var)) {
 263                 curl_save_cookies = git_config_bool(var, value);
 264                 return 0;
 265         }
 266
 267         if (!strcmp("http.postbuffer", var)) {
 268                 http_post_buffer = git_config_int(var, value);
 269                 if (http_post_buffer < LARGE_PACKET_MAX)
 270                         http_post_buffer = LARGE_PACKET_MAX;
 271                 return 0;
 272         }
 273
 274         if (!strcmp("http.useragent", var))
 275                 return git_config_string(&user_agent, var, value);
 276
 277         /* Fall back on the default ones */
 278         return git_default_config(var, value, cb);
 279 }
 280
 281 static void init_curl_http_auth(CURL *result)
 282 {
 283         if (!http_auth.username)
 284                 return;
 285
 286         credential_fill(&http_auth);
 287
 288 #if LIBCURL_VERSION_NUM >= 0x071301
 289         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 290         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 291 #else
 292         {
 293                 static struct strbuf up = STRBUF_INIT;
 294                 /*
 295                  * Note that we assume we only ever have a single set of
 296                  * credentials in a given program run, so we do not have
 297                  * to worry about updating this buffer, only setting its
 298                  * initial value.
 299                  */
 300                 if (!up.len)
 301                         strbuf_addf(&up, "%s:%s",
 302                                 http_auth.username, http_auth.password);
 303                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 304         }
 305 #endif
 306 }
 307
 308 static int has_cert_password(void)
 309 {
 310         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 311                 return 0;
 312         if (!cert_auth.password) {
 313                 cert_auth.protocol = xstrdup("cert");
 314                 cert_auth.username = xstrdup("");
 315                 cert_auth.path = xstrdup(ssl_cert);
 316                 credential_fill(&cert_auth);
 317         }
 318         return 1;
 319 }
 320
 321 #if LIBCURL_VERSION_NUM >= 0x071900
 322 static void set_curl_keepalive(CURL *c)
 323 {
 324         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 325 }
 326
 327 #elif LIBCURL_VERSION_NUM >= 0x071000
 328 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 329 {
 330         int ka = 1;
 331         int rc;
 332         socklen_t len = (socklen_t)sizeof(ka);
 333
 334         if (type != CURLSOCKTYPE_IPCXN)
 335                 return 0;
 336
 337         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 338         if (rc < 0)
 339                 warning("unable to set SO_KEEPALIVE on socket %s",
 340                         strerror(errno));
 341
 342         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 343 }
 344
 345 static void set_curl_keepalive(CURL *c)
 346 {
 347         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 348 }
 349
 350 #else
 351 static void set_curl_keepalive(CURL *c)
 352 {
 353         /* not supported on older curl versions */
 354 }
 355 #endif
 356
 357 static CURL *get_curl_handle(void)
 358 {
 359         CURL *result = curl_easy_init();
 360         long allowed_protocols = 0;
 361
 362         if (!result)
 363                 die("curl_easy_init failed");
 364
 365         if (!curl_ssl_verify) {
 366                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 367                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 368         } else {
 369                 /* Verify authenticity of the peer's certificate */
 370                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 371                 /* The name in the cert must match whom we tried to connect */
 372                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 373         }
 374
 375 #if LIBCURL_VERSION_NUM >= 0x070907
 376         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 377 #endif
 378 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 379         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 380 #endif
 381
 382         if (http_proactive_auth)
 383                 init_curl_http_auth(result);
 384
 385         if (getenv("GIT_SSL_VERSION"))
 386                 ssl_version = getenv("GIT_SSL_VERSION");
 387         if (ssl_version && *ssl_version) {
 388                 int i;
 389                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 390                         if (!strcmp(ssl_version, sslversions[i].name)) {
 391                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 392                                                  sslversions[i].ssl_version);
 393                                 break;
 394                         }
 395                 }
 396                 if (i == ARRAY_SIZE(sslversions))
 397                         warning("unsupported ssl version %s: using default",
 398                                 ssl_version);
 399         }
 400
 401         if (getenv("GIT_SSL_CIPHER_LIST"))
 402                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 403         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 404                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 405                                 ssl_cipherlist);
 406
 407         if (ssl_cert != NULL)
 408                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 409         if (has_cert_password())
 410                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 411 #if LIBCURL_VERSION_NUM >= 0x070903
 412         if (ssl_key != NULL)
 413                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 414 #endif
 415 #if LIBCURL_VERSION_NUM >= 0x070908
 416         if (ssl_capath != NULL)
 417                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 418 #endif
 419         if (ssl_cainfo != NULL)
 420                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 421
 422         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 423                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 424                                  curl_low_speed_limit);
 425                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 426                                  curl_low_speed_time);
 427         }
 428
 429         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 430         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 431 #if LIBCURL_VERSION_NUM >= 0x071301
 432         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 433 #elif LIBCURL_VERSION_NUM >= 0x071101
 434         curl_easy_setopt(result, CURLOPT_POST301, 1);
 435 #endif
 436 #if LIBCURL_VERSION_NUM >= 0x071304
 437         if (is_transport_allowed("http"))
 438                 allowed_protocols |= CURLPROTO_HTTP;
 439         if (is_transport_allowed("https"))
 440                 allowed_protocols |= CURLPROTO_HTTPS;
 441         if (is_transport_allowed("ftp"))
 442                 allowed_protocols |= CURLPROTO_FTP;
 443         if (is_transport_allowed("ftps"))
 444                 allowed_protocols |= CURLPROTO_FTPS;
 445         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 446 #else
 447         if (transport_restrict_protocols())
 448                 warning("protocol restrictions not applied to curl redirects because\n"
 449                         "your curl version is too old (>= 7.19.4)");
 450 #endif
 451
 452         if (getenv("GIT_CURL_VERBOSE"))
 453                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 454
 455         curl_easy_setopt(result, CURLOPT_USERAGENT,
 456                 user_agent ? user_agent : git_user_agent());
 457
 458         if (curl_ftp_no_epsv)
 459                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 460
 461 #ifdef CURLOPT_USE_SSL
 462         if (curl_ssl_try)
 463                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 464 #endif
 465
 466         if (curl_http_proxy) {
 467                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 468         }
 469 #if LIBCURL_VERSION_NUM >= 0x070a07
 470         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 471 #endif
 472
 473         set_curl_keepalive(result);
 474
 475         return result;
 476 }
 477
 478 static void set_from_env(const char **var, const char *envname)
 479 {
 480         const char *val = getenv(envname);
 481         if (val)
 482                 *var = val;
 483 }
 484
 485 void http_init(struct remote *remote, const char *url, int proactive_auth)
 486 {
 487         char *low_speed_limit;
 488         char *low_speed_time;
 489         char *normalized_url;
 490         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 491
 492         config.section = "http";
 493         config.key = NULL;
 494         config.collect_fn = http_options;
 495         config.cascade_fn = git_default_config;
 496         config.cb = NULL;
 497
 498         http_is_verbose = 0;
 499         normalized_url = url_normalize(url, &config.url);
 500
 501         git_config(urlmatch_config_entry, &config);
 502         free(normalized_url);
 503
 504         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 505                 die("curl_global_init failed");
 506
 507         http_proactive_auth = proactive_auth;
 508
 509         if (remote && remote->http_proxy)
 510                 curl_http_proxy = xstrdup(remote->http_proxy);
 511
 512         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 513         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 514
 515 #ifdef USE_CURL_MULTI
 516         {
 517                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 518                 if (http_max_requests != NULL)
 519                         max_requests = atoi(http_max_requests);
 520         }
 521
 522         curlm = curl_multi_init();
 523         if (!curlm)
 524                 die("curl_multi_init failed");
 525 #endif
 526
 527         if (getenv("GIT_SSL_NO_VERIFY"))
 528                 curl_ssl_verify = 0;
 529
 530         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 531 #if LIBCURL_VERSION_NUM >= 0x070903
 532         set_from_env(&ssl_key, "GIT_SSL_KEY");
 533 #endif
 534 #if LIBCURL_VERSION_NUM >= 0x070908
 535         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 536 #endif
 537         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 538
 539         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 540
 541         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 542         if (low_speed_limit != NULL)
 543                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 544         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 545         if (low_speed_time != NULL)
 546                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 547
 548         if (curl_ssl_verify == -1)
 549                 curl_ssl_verify = 1;
 550
 551         curl_session_count = 0;
 552 #ifdef USE_CURL_MULTI
 553         if (max_requests < 1)
 554                 max_requests = DEFAULT_MAX_REQUESTS;
 555 #endif
 556
 557         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 558                 curl_ftp_no_epsv = 1;
 559
 560         if (url) {
 561                 credential_from_url(&http_auth, url);
 562                 if (!ssl_cert_password_required &&
 563                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 564                     starts_with(url, "https://"))
 565                         ssl_cert_password_required = 1;
 566         }
 567
 568 #ifndef NO_CURL_EASY_DUPHANDLE
 569         curl_default = get_curl_handle();
 570 #endif
 571 }
 572
 573 void http_cleanup(void)
 574 {
 575         struct active_request_slot *slot = active_queue_head;
 576
 577         while (slot != NULL) {
 578                 struct active_request_slot *next = slot->next;
 579                 if (slot->curl != NULL) {
 580 #ifdef USE_CURL_MULTI
 581                         curl_multi_remove_handle(curlm, slot->curl);
 582 #endif
 583                         curl_easy_cleanup(slot->curl);
 584                 }
 585                 free(slot);
 586                 slot = next;
 587         }
 588         active_queue_head = NULL;
 589
 590 #ifndef NO_CURL_EASY_DUPHANDLE
 591         curl_easy_cleanup(curl_default);
 592 #endif
 593
 594 #ifdef USE_CURL_MULTI
 595         curl_multi_cleanup(curlm);
 596 #endif
 597         curl_global_cleanup();
 598
 599         curl_slist_free_all(pragma_header);
 600         pragma_header = NULL;
 601
 602         curl_slist_free_all(no_pragma_header);
 603         no_pragma_header = NULL;
 604
 605         if (curl_http_proxy) {
 606                 free((void *)curl_http_proxy);
 607                 curl_http_proxy = NULL;
 608         }
 609
 610         if (cert_auth.password != NULL) {
 611                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 612                 free(cert_auth.password);
 613                 cert_auth.password = NULL;
 614         }
 615         ssl_cert_password_required = 0;
 616
 617         free(cached_accept_language);
 618         cached_accept_language = NULL;
 619 }
 620
 621 struct active_request_slot *get_active_slot(void)
 622 {
 623         struct active_request_slot *slot = active_queue_head;
 624         struct active_request_slot *newslot;
 625
 626 #ifdef USE_CURL_MULTI
 627         int num_transfers;
 628
 629         /* Wait for a slot to open up if the queue is full */
 630         while (active_requests >= max_requests) {
 631                 curl_multi_perform(curlm, &num_transfers);
 632                 if (num_transfers < active_requests)
 633                         process_curl_messages();
 634         }
 635 #endif
 636
 637         while (slot != NULL && slot->in_use)
 638                 slot = slot->next;
 639
 640         if (slot == NULL) {
 641                 newslot = xmalloc(sizeof(*newslot));
 642                 newslot->curl = NULL;
 643                 newslot->in_use = 0;
 644                 newslot->next = NULL;
 645
 646                 slot = active_queue_head;
 647                 if (slot == NULL) {
 648                         active_queue_head = newslot;
 649                 } else {
 650                         while (slot->next != NULL)
 651                                 slot = slot->next;
 652                         slot->next = newslot;
 653                 }
 654                 slot = newslot;
 655         }
 656
 657         if (slot->curl == NULL) {
 658 #ifdef NO_CURL_EASY_DUPHANDLE
 659                 slot->curl = get_curl_handle();
 660 #else
 661                 slot->curl = curl_easy_duphandle(curl_default);
 662 #endif
 663                 curl_session_count++;
 664         }
 665
 666         active_requests++;
 667         slot->in_use = 1;
 668         slot->results = NULL;
 669         slot->finished = NULL;
 670         slot->callback_data = NULL;
 671         slot->callback_func = NULL;
 672         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 673         if (curl_save_cookies)
 674                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 675         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 676         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 677         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 678         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 679         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 680         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 681         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 682         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 683         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 684 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 685         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 686 #endif
 687         if (http_auth.password)
 688                 init_curl_http_auth(slot->curl);
 689
 690         return slot;
 691 }
 692
 693 int start_active_slot(struct active_request_slot *slot)
 694 {
 695 #ifdef USE_CURL_MULTI
 696         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 697         int num_transfers;
 698
 699         if (curlm_result != CURLM_OK &&
 700             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 701                 active_requests--;
 702                 slot->in_use = 0;
 703                 return 0;
 704         }
 705
 706         /*
 707          * We know there must be something to do, since we just added
 708          * something.
 709          */
 710         curl_multi_perform(curlm, &num_transfers);
 711 #endif
 712         return 1;
 713 }
 714
 715 #ifdef USE_CURL_MULTI
 716 struct fill_chain {
 717         void *data;
 718         int (*fill)(void *);
 719         struct fill_chain *next;
 720 };
 721
 722 static struct fill_chain *fill_cfg;
 723
 724 void add_fill_function(void *data, int (*fill)(void *))
 725 {
 726         struct fill_chain *new = xmalloc(sizeof(*new));
 727         struct fill_chain **linkp = &fill_cfg;
 728         new->data = data;
 729         new->fill = fill;
 730         new->next = NULL;
 731         while (*linkp)
 732                 linkp = &(*linkp)->next;
 733         *linkp = new;
 734 }
 735
 736 void fill_active_slots(void)
 737 {
 738         struct active_request_slot *slot = active_queue_head;
 739
 740         while (active_requests < max_requests) {
 741                 struct fill_chain *fill;
 742                 for (fill = fill_cfg; fill; fill = fill->next)
 743                         if (fill->fill(fill->data))
 744                                 break;
 745
 746                 if (!fill)
 747                         break;
 748         }
 749
 750         while (slot != NULL) {
 751                 if (!slot->in_use && slot->curl != NULL
 752                         && curl_session_count > min_curl_sessions) {
 753                         curl_easy_cleanup(slot->curl);
 754                         slot->curl = NULL;
 755                         curl_session_count--;
 756                 }
 757                 slot = slot->next;
 758         }
 759 }
 760
 761 void step_active_slots(void)
 762 {
 763         int num_transfers;
 764         CURLMcode curlm_result;
 765
 766         do {
 767                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 768         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 769         if (num_transfers < active_requests) {
 770                 process_curl_messages();
 771                 fill_active_slots();
 772         }
 773 }
 774 #endif
 775
 776 void run_active_slot(struct active_request_slot *slot)
 777 {
 778 #ifdef USE_CURL_MULTI
 779         fd_set readfds;
 780         fd_set writefds;
 781         fd_set excfds;
 782         int max_fd;
 783         struct timeval select_timeout;
 784         int finished = 0;
 785
 786         slot->finished = &finished;
 787         while (!finished) {
 788                 step_active_slots();
 789
 790                 if (slot->in_use) {
 791 #if LIBCURL_VERSION_NUM >= 0x070f04
 792                         long curl_timeout;
 793                         curl_multi_timeout(curlm, &curl_timeout);
 794                         if (curl_timeout == 0) {
 795                                 continue;
 796                         } else if (curl_timeout == -1) {
 797                                 select_timeout.tv_sec  = 0;
 798                                 select_timeout.tv_usec = 50000;
 799                         } else {
 800                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 801                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 802                         }
 803 #else
 804                         select_timeout.tv_sec  = 0;
 805                         select_timeout.tv_usec = 50000;
 806 #endif
 807
 808                         max_fd = -1;
 809                         FD_ZERO(&readfds);
 810                         FD_ZERO(&writefds);
 811                         FD_ZERO(&excfds);
 812                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 813
 814                         /*
 815                          * It can happen that curl_multi_timeout returns a pathologically
 816                          * long timeout when curl_multi_fdset returns no file descriptors
 817                          * to read.  See commit message for more details.
 818                          */
 819                         if (max_fd < 0 &&
 820                             (select_timeout.tv_sec > 0 ||
 821                              select_timeout.tv_usec > 50000)) {
 822                                 select_timeout.tv_sec  = 0;
 823                                 select_timeout.tv_usec = 50000;
 824                         }
 825
 826                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 827                 }
 828         }
 829 #else
 830         while (slot->in_use) {
 831                 slot->curl_result = curl_easy_perform(slot->curl);
 832                 finish_active_slot(slot);
 833         }
 834 #endif
 835 }
 836
 837 static void release_active_slot(struct active_request_slot *slot)
 838 {
 839         closedown_active_slot(slot);
 840         if (slot->curl && curl_session_count > min_curl_sessions) {
 841 #ifdef USE_CURL_MULTI
 842                 curl_multi_remove_handle(curlm, slot->curl);
 843 #endif
 844                 curl_easy_cleanup(slot->curl);
 845                 slot->curl = NULL;
 846                 curl_session_count--;
 847         }
 848 #ifdef USE_CURL_MULTI
 849         fill_active_slots();
 850 #endif
 851 }
 852
 853 void finish_all_active_slots(void)
 854 {
 855         struct active_request_slot *slot = active_queue_head;
 856
 857         while (slot != NULL)
 858                 if (slot->in_use) {
 859                         run_active_slot(slot);
 860                         slot = active_queue_head;
 861                 } else {
 862                         slot = slot->next;
 863                 }
 864 }
 865
 866 /* Helpers for modifying and creating URLs */
 867 static inline int needs_quote(int ch)
 868 {
 869         if (((ch >= 'A') && (ch <= 'Z'))
 870                         || ((ch >= 'a') && (ch <= 'z'))
 871                         || ((ch >= '0') && (ch <= '9'))
 872                         || (ch == '/')
 873                         || (ch == '-')
 874                         || (ch == '.'))
 875                 return 0;
 876         return 1;
 877 }
 878
 879 static char *quote_ref_url(const char *base, const char *ref)
 880 {
 881         struct strbuf buf = STRBUF_INIT;
 882         const char *cp;
 883         int ch;
 884
 885         end_url_with_slash(&buf, base);
 886
 887         for (cp = ref; (ch = *cp) != 0; cp++)
 888                 if (needs_quote(ch))
 889                         strbuf_addf(&buf, "%%%02x", ch);
 890                 else
 891                         strbuf_addch(&buf, *cp);
 892
 893         return strbuf_detach(&buf, NULL);
 894 }
 895
 896 void append_remote_object_url(struct strbuf *buf, const char *url,
 897                               const char *hex,
 898                               int only_two_digit_prefix)
 899 {
 900         end_url_with_slash(buf, url);
 901
 902         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 903         if (!only_two_digit_prefix)
 904                 strbuf_addf(buf, "%s", hex+2);
 905 }
 906
 907 char *get_remote_object_url(const char *url, const char *hex,
 908                             int only_two_digit_prefix)
 909 {
 910         struct strbuf buf = STRBUF_INIT;
 911         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 912         return strbuf_detach(&buf, NULL);
 913 }
 914
 915 static int handle_curl_result(struct slot_results *results)
 916 {
 917         /*
 918          * If we see a failing http code with CURLE_OK, we have turned off
 919          * FAILONERROR (to keep the server's custom error response), and should
 920          * translate the code into failure here.
 921          */
 922         if (results->curl_result == CURLE_OK &&
 923             results->http_code >= 400) {
 924                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 925                 /*
 926                  * Normally curl will already have put the "reason phrase"
 927                  * from the server into curl_errorstr; unfortunately without
 928                  * FAILONERROR it is lost, so we can give only the numeric
 929                  * status code.
 930                  */
 931                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 932                          "The requested URL returned error: %ld",
 933                          results->http_code);
 934         }
 935
 936         if (results->curl_result == CURLE_OK) {
 937                 credential_approve(&http_auth);
 938                 return HTTP_OK;
 939         } else if (missing_target(results))
 940                 return HTTP_MISSING_TARGET;
 941         else if (results->http_code == 401) {
 942                 if (http_auth.username && http_auth.password) {
 943                         credential_reject(&http_auth);
 944                         return HTTP_NOAUTH;
 945                 } else {
 946 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 947                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
 948 #endif
 949                         return HTTP_REAUTH;
 950                 }
 951         } else {
 952 #if LIBCURL_VERSION_NUM >= 0x070c00
 953                 if (!curl_errorstr[0])
 954                         strlcpy(curl_errorstr,
 955                                 curl_easy_strerror(results->curl_result),
 956                                 sizeof(curl_errorstr));
 957 #endif
 958                 return HTTP_ERROR;
 959         }
 960 }
 961
 962 int run_one_slot(struct active_request_slot *slot,
 963                  struct slot_results *results)
 964 {
 965         slot->results = results;
 966         if (!start_active_slot(slot)) {
 967                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 968                          "failed to start HTTP request");
 969                 return HTTP_START_FAILED;
 970         }
 971
 972         run_active_slot(slot);
 973         return handle_curl_result(results);
 974 }
 975
 976 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 977 {
 978         char *ptr;
 979         CURLcode ret;
 980
 981         strbuf_reset(buf);
 982         ret = curl_easy_getinfo(curl, info, &ptr);
 983         if (!ret && ptr)
 984                 strbuf_addstr(buf, ptr);
 985         return ret;
 986 }
 987
 988 /*
 989  * Check for and extract a content-type parameter. "raw"
 990  * should be positioned at the start of the potential
 991  * parameter, with any whitespace already removed.
 992  *
 993  * "name" is the name of the parameter. The value is appended
 994  * to "out".
 995  */
 996 static int extract_param(const char *raw, const char *name,
 997                          struct strbuf *out)
 998 {
 999         size_t len = strlen(name);
1000
1001         if (strncasecmp(raw, name, len))
1002                 return -1;
1003         raw += len;
1004
1005         if (*raw != '=')
1006                 return -1;
1007         raw++;
1008
1009         while (*raw && !isspace(*raw) && *raw != ';')
1010                 strbuf_addch(out, *raw++);
1011         return 0;
1012 }
1013
1014 /*
1015  * Extract a normalized version of the content type, with any
1016  * spaces suppressed, all letters lowercased, and no trailing ";"
1017  * or parameters.
1018  *
1019  * Note that we will silently remove even invalid whitespace. For
1020  * example, "text / plain" is specifically forbidden by RFC 2616,
1021  * but "text/plain" is the only reasonable output, and this keeps
1022  * our code simple.
1023  *
1024  * If the "charset" argument is not NULL, store the value of any
1025  * charset parameter there.
1026  *
1027  * Example:
1028  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1029  *   "text / plain" -> "text/plain"
1030  */
1031 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1032                                  struct strbuf *charset)
1033 {
1034         const char *p;
1035
1036         strbuf_reset(type);
1037         strbuf_grow(type, raw->len);
1038         for (p = raw->buf; *p; p++) {
1039                 if (isspace(*p))
1040                         continue;
1041                 if (*p == ';') {
1042                         p++;
1043                         break;
1044                 }
1045                 strbuf_addch(type, tolower(*p));
1046         }
1047
1048         if (!charset)
1049                 return;
1050
1051         strbuf_reset(charset);
1052         while (*p) {
1053                 while (isspace(*p) || *p == ';')
1054                         p++;
1055                 if (!extract_param(p, "charset", charset))
1056                         return;
1057                 while (*p && !isspace(*p))
1058                         p++;
1059         }
1060
1061         if (!charset->len && starts_with(type->buf, "text/"))
1062                 strbuf_addstr(charset, "ISO-8859-1");
1063 }
1064
1065 static void write_accept_language(struct strbuf *buf)
1066 {
1067         /*
1068          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1069          * that, q-value will be smaller than 0.001, the minimum q-value the
1070          * HTTP specification allows. See
1071          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1072          */
1073         const int MAX_DECIMAL_PLACES = 3;
1074         const int MAX_LANGUAGE_TAGS = 1000;
1075         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1076         char **language_tags = NULL;
1077         int num_langs = 0;
1078         const char *s = get_preferred_languages();
1079         int i;
1080         struct strbuf tag = STRBUF_INIT;
1081
1082         /* Don't add Accept-Language header if no language is preferred. */
1083         if (!s)
1084                 return;
1085
1086         /*
1087          * Split the colon-separated string of preferred languages into
1088          * language_tags array.
1089          */
1090         do {
1091                 /* collect language tag */
1092                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1093                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1094
1095                 /* skip .codeset, @modifier and any other unnecessary parts */
1096                 while (*s && *s != ':')
1097                         s++;
1098
1099                 if (tag.len) {
1100                         num_langs++;
1101                         REALLOC_ARRAY(language_tags, num_langs);
1102                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1103                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1104                                 break;
1105                 }
1106         } while (*s++);
1107
1108         /* write Accept-Language header into buf */
1109         if (num_langs) {
1110                 int last_buf_len = 0;
1111                 int max_q;
1112                 int decimal_places;
1113                 char q_format[32];
1114
1115                 /* add '*' */
1116                 REALLOC_ARRAY(language_tags, num_langs + 1);
1117                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1118
1119                 /* compute decimal_places */
1120                 for (max_q = 1, decimal_places = 0;
1121                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1122                      decimal_places++, max_q *= 10)
1123                         ;
1124
1125                 sprintf(q_format, ";q=0.%%0%dd", decimal_places);
1126
1127                 strbuf_addstr(buf, "Accept-Language: ");
1128
1129                 for (i = 0; i < num_langs; i++) {
1130                         if (i > 0)
1131                                 strbuf_addstr(buf, ", ");
1132
1133                         strbuf_addstr(buf, language_tags[i]);
1134
1135                         if (i > 0)
1136                                 strbuf_addf(buf, q_format, max_q - i);
1137
1138                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1139                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1140                                 break;
1141                         }
1142
1143                         last_buf_len = buf->len;
1144                 }
1145         }
1146
1147         /* free language tags -- last one is a static '*' */
1148         for (i = 0; i < num_langs - 1; i++)
1149                 free(language_tags[i]);
1150         free(language_tags);
1151 }
1152
1153 /*
1154  * Get an Accept-Language header which indicates user's preferred languages.
1155  *
1156  * Examples:
1157  *   LANGUAGE= -> ""
1158  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1159  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1160  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1161  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1162  *   LANGUAGE= LANG=C -> ""
1163  */
1164 static const char *get_accept_language(void)
1165 {
1166         if (!cached_accept_language) {
1167                 struct strbuf buf = STRBUF_INIT;
1168                 write_accept_language(&buf);
1169                 if (buf.len > 0)
1170                         cached_accept_language = strbuf_detach(&buf, NULL);
1171         }
1172
1173         return cached_accept_language;
1174 }
1175
1176 /* http_request() targets */
1177 #define HTTP_REQUEST_STRBUF     0
1178 #define HTTP_REQUEST_FILE       1
1179
1180 static int http_request(const char *url,
1181                         void *result, int target,
1182                         const struct http_get_options *options)
1183 {
1184         struct active_request_slot *slot;
1185         struct slot_results results;
1186         struct curl_slist *headers = NULL;
1187         struct strbuf buf = STRBUF_INIT;
1188         const char *accept_language;
1189         int ret;
1190
1191         slot = get_active_slot();
1192         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1193
1194         if (result == NULL) {
1195                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1196         } else {
1197                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1198                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1199
1200                 if (target == HTTP_REQUEST_FILE) {
1201                         long posn = ftell(result);
1202                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1203                                          fwrite);
1204                         if (posn > 0) {
1205                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1206                                 headers = curl_slist_append(headers, buf.buf);
1207                                 strbuf_reset(&buf);
1208                         }
1209                 } else
1210                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1211                                          fwrite_buffer);
1212         }
1213
1214         accept_language = get_accept_language();
1215
1216         if (accept_language)
1217                 headers = curl_slist_append(headers, accept_language);
1218
1219         strbuf_addstr(&buf, "Pragma:");
1220         if (options && options->no_cache)
1221                 strbuf_addstr(&buf, " no-cache");
1222         if (options && options->keep_error)
1223                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1224
1225         headers = curl_slist_append(headers, buf.buf);
1226
1227         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1228         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1229         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1230
1231         ret = run_one_slot(slot, &results);
1232
1233         if (options && options->content_type) {
1234                 struct strbuf raw = STRBUF_INIT;
1235                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1236                 extract_content_type(&raw, options->content_type,
1237                                      options->charset);
1238                 strbuf_release(&raw);
1239         }
1240
1241         if (options && options->effective_url)
1242                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1243                                 options->effective_url);
1244
1245         curl_slist_free_all(headers);
1246         strbuf_release(&buf);
1247
1248         return ret;
1249 }
1250
1251 /*
1252  * Update the "base" url to a more appropriate value, as deduced by
1253  * redirects seen when requesting a URL starting with "url".
1254  *
1255  * The "asked" parameter is a URL that we asked curl to access, and must begin
1256  * with "base".
1257  *
1258  * The "got" parameter is the URL that curl reported to us as where we ended
1259  * up.
1260  *
1261  * Returns 1 if we updated the base url, 0 otherwise.
1262  *
1263  * Our basic strategy is to compare "base" and "asked" to find the bits
1264  * specific to our request. We then strip those bits off of "got" to yield the
1265  * new base. So for example, if our base is "http://example.com/foo.git",
1266  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1267  * with "https://other.example.com/foo.git/info/refs". We would want the
1268  * new URL to become "https://other.example.com/foo.git".
1269  *
1270  * Note that this assumes a sane redirect scheme. It's entirely possible
1271  * in the example above to end up at a URL that does not even end in
1272  * "info/refs".  In such a case we simply punt, as there is not much we can
1273  * do (and such a scheme is unlikely to represent a real git repository,
1274  * which means we are likely about to abort anyway).
1275  */
1276 static int update_url_from_redirect(struct strbuf *base,
1277                                     const char *asked,
1278                                     const struct strbuf *got)
1279 {
1280         const char *tail;
1281         size_t tail_len;
1282
1283         if (!strcmp(asked, got->buf))
1284                 return 0;
1285
1286         if (!skip_prefix(asked, base->buf, &tail))
1287                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1288                     asked, base->buf);
1289
1290         tail_len = strlen(tail);
1291
1292         if (got->len < tail_len ||
1293             strcmp(tail, got->buf + got->len - tail_len))
1294                 return 0; /* insane redirect scheme */
1295
1296         strbuf_reset(base);
1297         strbuf_add(base, got->buf, got->len - tail_len);
1298         return 1;
1299 }
1300
1301 static int http_request_reauth(const char *url,
1302                                void *result, int target,
1303                                struct http_get_options *options)
1304 {
1305         int ret = http_request(url, result, target, options);
1306
1307         if (options && options->effective_url && options->base_url) {
1308                 if (update_url_from_redirect(options->base_url,
1309                                              url, options->effective_url)) {
1310                         credential_from_url(&http_auth, options->base_url->buf);
1311                         url = options->effective_url->buf;
1312                 }
1313         }
1314
1315         if (ret != HTTP_REAUTH)
1316                 return ret;
1317
1318         /*
1319          * If we are using KEEP_ERROR, the previous request may have
1320          * put cruft into our output stream; we should clear it out before
1321          * making our next request. We only know how to do this for
1322          * the strbuf case, but that is enough to satisfy current callers.
1323          */
1324         if (options && options->keep_error) {
1325                 switch (target) {
1326                 case HTTP_REQUEST_STRBUF:
1327                         strbuf_reset(result);
1328                         break;
1329                 default:
1330                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1331                 }
1332         }
1333
1334         credential_fill(&http_auth);
1335
1336         return http_request(url, result, target, options);
1337 }
1338
1339 int http_get_strbuf(const char *url,
1340                     struct strbuf *result,
1341                     struct http_get_options *options)
1342 {
1343         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1344 }
1345
1346 /*
1347  * Downloads a URL and stores the result in the given file.
1348  *
1349  * If a previous interrupted download is detected (i.e. a previous temporary
1350  * file is still around) the download is resumed.
1351  */
1352 static int http_get_file(const char *url, const char *filename,
1353                          struct http_get_options *options)
1354 {
1355         int ret;
1356         struct strbuf tmpfile = STRBUF_INIT;
1357         FILE *result;
1358
1359         strbuf_addf(&tmpfile, "%s.temp", filename);
1360         result = fopen(tmpfile.buf, "a");
1361         if (!result) {
1362                 error("Unable to open local file %s", tmpfile.buf);
1363                 ret = HTTP_ERROR;
1364                 goto cleanup;
1365         }
1366
1367         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1368         fclose(result);
1369
1370         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1371                 ret = HTTP_ERROR;
1372 cleanup:
1373         strbuf_release(&tmpfile);
1374         return ret;
1375 }
1376
1377 int http_fetch_ref(const char *base, struct ref *ref)
1378 {
1379         struct http_get_options options = {0};
1380         char *url;
1381         struct strbuf buffer = STRBUF_INIT;
1382         int ret = -1;
1383
1384         options.no_cache = 1;
1385
1386         url = quote_ref_url(base, ref->name);
1387         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1388                 strbuf_rtrim(&buffer);
1389                 if (buffer.len == 40)
1390                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1391                 else if (starts_with(buffer.buf, "ref: ")) {
1392                         ref->symref = xstrdup(buffer.buf + 5);
1393                         ret = 0;
1394                 }
1395         }
1396
1397         strbuf_release(&buffer);
1398         free(url);
1399         return ret;
1400 }
1401
1402 /* Helpers for fetching packs */
1403 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1404 {
1405         char *url, *tmp;
1406         struct strbuf buf = STRBUF_INIT;
1407
1408         if (http_is_verbose)
1409                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1410
1411         end_url_with_slash(&buf, base_url);
1412         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1413         url = strbuf_detach(&buf, NULL);
1414
1415         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1416         tmp = strbuf_detach(&buf, NULL);
1417
1418         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1419                 error("Unable to get pack index %s", url);
1420                 free(tmp);
1421                 tmp = NULL;
1422         }
1423
1424         free(url);
1425         return tmp;
1426 }
1427
1428 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1429         unsigned char *sha1, const char *base_url)
1430 {
1431         struct packed_git *new_pack;
1432         char *tmp_idx = NULL;
1433         int ret;
1434
1435         if (has_pack_index(sha1)) {
1436                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1437                 if (!new_pack)
1438                         return -1; /* parse_pack_index() already issued error message */
1439                 goto add_pack;
1440         }
1441
1442         tmp_idx = fetch_pack_index(sha1, base_url);
1443         if (!tmp_idx)
1444                 return -1;
1445
1446         new_pack = parse_pack_index(sha1, tmp_idx);
1447         if (!new_pack) {
1448                 unlink(tmp_idx);
1449                 free(tmp_idx);
1450
1451                 return -1; /* parse_pack_index() already issued error message */
1452         }
1453
1454         ret = verify_pack_index(new_pack);
1455         if (!ret) {
1456                 close_pack_index(new_pack);
1457                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1458         }
1459         free(tmp_idx);
1460         if (ret)
1461                 return -1;
1462
1463 add_pack:
1464         new_pack->next = *packs_head;
1465         *packs_head = new_pack;
1466         return 0;
1467 }
1468
1469 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1470 {
1471         struct http_get_options options = {0};
1472         int ret = 0, i = 0;
1473         char *url, *data;
1474         struct strbuf buf = STRBUF_INIT;
1475         unsigned char sha1[20];
1476
1477         end_url_with_slash(&buf, base_url);
1478         strbuf_addstr(&buf, "objects/info/packs");
1479         url = strbuf_detach(&buf, NULL);
1480
1481         options.no_cache = 1;
1482         ret = http_get_strbuf(url, &buf, &options);
1483         if (ret != HTTP_OK)
1484                 goto cleanup;
1485
1486         data = buf.buf;
1487         while (i < buf.len) {
1488                 switch (data[i]) {
1489                 case 'P':
1490                         i++;
1491                         if (i + 52 <= buf.len &&
1492                             starts_with(data + i, " pack-") &&
1493                             starts_with(data + i + 46, ".pack\n")) {
1494                                 get_sha1_hex(data + i + 6, sha1);
1495                                 fetch_and_setup_pack_index(packs_head, sha1,
1496                                                       base_url);
1497                                 i += 51;
1498                                 break;
1499                         }
1500                 default:
1501                         while (i < buf.len && data[i] != '\n')
1502                                 i++;
1503                 }
1504                 i++;
1505         }
1506
1507 cleanup:
1508         free(url);
1509         return ret;
1510 }
1511
1512 void release_http_pack_request(struct http_pack_request *preq)
1513 {
1514         if (preq->packfile != NULL) {
1515                 fclose(preq->packfile);
1516                 preq->packfile = NULL;
1517         }
1518         if (preq->range_header != NULL) {
1519                 curl_slist_free_all(preq->range_header);
1520                 preq->range_header = NULL;
1521         }
1522         preq->slot = NULL;
1523         free(preq->url);
1524         free(preq);
1525 }
1526
1527 int finish_http_pack_request(struct http_pack_request *preq)
1528 {
1529         struct packed_git **lst;
1530         struct packed_git *p = preq->target;
1531         char *tmp_idx;
1532         struct child_process ip = CHILD_PROCESS_INIT;
1533         const char *ip_argv[8];
1534
1535         close_pack_index(p);
1536
1537         fclose(preq->packfile);
1538         preq->packfile = NULL;
1539
1540         lst = preq->lst;
1541         while (*lst != p)
1542                 lst = &((*lst)->next);
1543         *lst = (*lst)->next;
1544
1545         tmp_idx = xstrdup(preq->tmpfile);
1546         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1547                ".idx.temp");
1548
1549         ip_argv[0] = "index-pack";
1550         ip_argv[1] = "-o";
1551         ip_argv[2] = tmp_idx;
1552         ip_argv[3] = preq->tmpfile;
1553         ip_argv[4] = NULL;
1554
1555         ip.argv = ip_argv;
1556         ip.git_cmd = 1;
1557         ip.no_stdin = 1;
1558         ip.no_stdout = 1;
1559
1560         if (run_command(&ip)) {
1561                 unlink(preq->tmpfile);
1562                 unlink(tmp_idx);
1563                 free(tmp_idx);
1564                 return -1;
1565         }
1566
1567         unlink(sha1_pack_index_name(p->sha1));
1568
1569         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1570          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1571                 free(tmp_idx);
1572                 return -1;
1573         }
1574
1575         install_packed_git(p);
1576         free(tmp_idx);
1577         return 0;
1578 }
1579
1580 struct http_pack_request *new_http_pack_request(
1581         struct packed_git *target, const char *base_url)
1582 {
1583         long prev_posn = 0;
1584         char range[RANGE_HEADER_SIZE];
1585         struct strbuf buf = STRBUF_INIT;
1586         struct http_pack_request *preq;
1587
1588         preq = xcalloc(1, sizeof(*preq));
1589         preq->target = target;
1590
1591         end_url_with_slash(&buf, base_url);
1592         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1593                 sha1_to_hex(target->sha1));
1594         preq->url = strbuf_detach(&buf, NULL);
1595
1596         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1597                 sha1_pack_name(target->sha1));
1598         preq->packfile = fopen(preq->tmpfile, "a");
1599         if (!preq->packfile) {
1600                 error("Unable to open local file %s for pack",
1601                       preq->tmpfile);
1602                 goto abort;
1603         }
1604
1605         preq->slot = get_active_slot();
1606         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1607         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1608         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1609         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1610                 no_pragma_header);
1611
1612         /*
1613          * If there is data present from a previous transfer attempt,
1614          * resume where it left off
1615          */
1616         prev_posn = ftell(preq->packfile);
1617         if (prev_posn>0) {
1618                 if (http_is_verbose)
1619                         fprintf(stderr,
1620                                 "Resuming fetch of pack %s at byte %ld\n",
1621                                 sha1_to_hex(target->sha1), prev_posn);
1622                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1623                 preq->range_header = curl_slist_append(NULL, range);
1624                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1625                         preq->range_header);
1626         }
1627
1628         return preq;
1629
1630 abort:
1631         free(preq->url);
1632         free(preq);
1633         return NULL;
1634 }
1635
1636 /* Helpers for fetching objects (loose) */
1637 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1638                                void *data)
1639 {
1640         unsigned char expn[4096];
1641         size_t size = eltsize * nmemb;
1642         int posn = 0;
1643         struct http_object_request *freq =
1644                 (struct http_object_request *)data;
1645         do {
1646                 ssize_t retval = xwrite(freq->localfile,
1647                                         (char *) ptr + posn, size - posn);
1648                 if (retval < 0)
1649                         return posn;
1650                 posn += retval;
1651         } while (posn < size);
1652
1653         freq->stream.avail_in = size;
1654         freq->stream.next_in = (void *)ptr;
1655         do {
1656                 freq->stream.next_out = expn;
1657                 freq->stream.avail_out = sizeof(expn);
1658                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1659                 git_SHA1_Update(&freq->c, expn,
1660                                 sizeof(expn) - freq->stream.avail_out);
1661         } while (freq->stream.avail_in && freq->zret == Z_OK);
1662         return size;
1663 }
1664
1665 struct http_object_request *new_http_object_request(const char *base_url,
1666         unsigned char *sha1)
1667 {
1668         char *hex = sha1_to_hex(sha1);
1669         const char *filename;
1670         char prevfile[PATH_MAX];
1671         int prevlocal;
1672         char prev_buf[PREV_BUF_SIZE];
1673         ssize_t prev_read = 0;
1674         long prev_posn = 0;
1675         char range[RANGE_HEADER_SIZE];
1676         struct curl_slist *range_header = NULL;
1677         struct http_object_request *freq;
1678
1679         freq = xcalloc(1, sizeof(*freq));
1680         hashcpy(freq->sha1, sha1);
1681         freq->localfile = -1;
1682
1683         filename = sha1_file_name(sha1);
1684         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1685                  "%s.temp", filename);
1686
1687         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1688         unlink_or_warn(prevfile);
1689         rename(freq->tmpfile, prevfile);
1690         unlink_or_warn(freq->tmpfile);
1691
1692         if (freq->localfile != -1)
1693                 error("fd leakage in start: %d", freq->localfile);
1694         freq->localfile = open(freq->tmpfile,
1695                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1696         /*
1697          * This could have failed due to the "lazy directory creation";
1698          * try to mkdir the last path component.
1699          */
1700         if (freq->localfile < 0 && errno == ENOENT) {
1701                 char *dir = strrchr(freq->tmpfile, '/');
1702                 if (dir) {
1703                         *dir = 0;
1704                         mkdir(freq->tmpfile, 0777);
1705                         *dir = '/';
1706                 }
1707                 freq->localfile = open(freq->tmpfile,
1708                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1709         }
1710
1711         if (freq->localfile < 0) {
1712                 error("Couldn't create temporary file %s: %s",
1713                       freq->tmpfile, strerror(errno));
1714                 goto abort;
1715         }
1716
1717         git_inflate_init(&freq->stream);
1718
1719         git_SHA1_Init(&freq->c);
1720
1721         freq->url = get_remote_object_url(base_url, hex, 0);
1722
1723         /*
1724          * If a previous temp file is present, process what was already
1725          * fetched.
1726          */
1727         prevlocal = open(prevfile, O_RDONLY);
1728         if (prevlocal != -1) {
1729                 do {
1730                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1731                         if (prev_read>0) {
1732                                 if (fwrite_sha1_file(prev_buf,
1733                                                      1,
1734                                                      prev_read,
1735                                                      freq) == prev_read) {
1736                                         prev_posn += prev_read;
1737                                 } else {
1738                                         prev_read = -1;
1739                                 }
1740                         }
1741                 } while (prev_read > 0);
1742                 close(prevlocal);
1743         }
1744         unlink_or_warn(prevfile);
1745
1746         /*
1747          * Reset inflate/SHA1 if there was an error reading the previous temp
1748          * file; also rewind to the beginning of the local file.
1749          */
1750         if (prev_read == -1) {
1751                 memset(&freq->stream, 0, sizeof(freq->stream));
1752                 git_inflate_init(&freq->stream);
1753                 git_SHA1_Init(&freq->c);
1754                 if (prev_posn>0) {
1755                         prev_posn = 0;
1756                         lseek(freq->localfile, 0, SEEK_SET);
1757                         if (ftruncate(freq->localfile, 0) < 0) {
1758                                 error("Couldn't truncate temporary file %s: %s",
1759                                           freq->tmpfile, strerror(errno));
1760                                 goto abort;
1761                         }
1762                 }
1763         }
1764
1765         freq->slot = get_active_slot();
1766
1767         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1768         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1769         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1770         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1771         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1772
1773         /*
1774          * If we have successfully processed data from a previous fetch
1775          * attempt, only fetch the data we don't already have.
1776          */
1777         if (prev_posn>0) {
1778                 if (http_is_verbose)
1779                         fprintf(stderr,
1780                                 "Resuming fetch of object %s at byte %ld\n",
1781                                 hex, prev_posn);
1782                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1783                 range_header = curl_slist_append(range_header, range);
1784                 curl_easy_setopt(freq->slot->curl,
1785                                  CURLOPT_HTTPHEADER, range_header);
1786         }
1787
1788         return freq;
1789
1790 abort:
1791         free(freq->url);
1792         free(freq);
1793         return NULL;
1794 }
1795
1796 void process_http_object_request(struct http_object_request *freq)
1797 {
1798         if (freq->slot == NULL)
1799                 return;
1800         freq->curl_result = freq->slot->curl_result;
1801         freq->http_code = freq->slot->http_code;
1802         freq->slot = NULL;
1803 }
1804
1805 int finish_http_object_request(struct http_object_request *freq)
1806 {
1807         struct stat st;
1808
1809         close(freq->localfile);
1810         freq->localfile = -1;
1811
1812         process_http_object_request(freq);
1813
1814         if (freq->http_code == 416) {
1815                 warning("requested range invalid; we may already have all the data.");
1816         } else if (freq->curl_result != CURLE_OK) {
1817                 if (stat(freq->tmpfile, &st) == 0)
1818                         if (st.st_size == 0)
1819                                 unlink_or_warn(freq->tmpfile);
1820                 return -1;
1821         }
1822
1823         git_inflate_end(&freq->stream);
1824         git_SHA1_Final(freq->real_sha1, &freq->c);
1825         if (freq->zret != Z_STREAM_END) {
1826                 unlink_or_warn(freq->tmpfile);
1827                 return -1;
1828         }
1829         if (hashcmp(freq->sha1, freq->real_sha1)) {
1830                 unlink_or_warn(freq->tmpfile);
1831                 return -1;
1832         }
1833         freq->rename =
1834                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
1835
1836         return freq->rename;
1837 }
1838
1839 void abort_http_object_request(struct http_object_request *freq)
1840 {
1841         unlink_or_warn(freq->tmpfile);
1842
1843         release_http_object_request(freq);
1844 }
1845
1846 void release_http_object_request(struct http_object_request *freq)
1847 {
1848         if (freq->localfile != -1) {
1849                 close(freq->localfile);
1850                 freq->localfile = -1;
1851         }
1852         if (freq->url != NULL) {
1853                 free(freq->url);
1854                 freq->url = NULL;
1855         }
1856         if (freq->slot != NULL) {
1857                 freq->slot->callback_func = NULL;
1858                 freq->slot->callback_data = NULL;
1859                 release_active_slot(freq->slot);
1860                 freq->slot = NULL;
1861         }
1862 }