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
  34 char curl_errorstr[CURL_ERROR_SIZE];
  35
  36 static int curl_ssl_verify = -1;
  37 static int curl_ssl_try;
  38 static const char *ssl_cert;
  39 static const char *ssl_cipherlist;
  40 static const char *ssl_version;
  41 static struct {
  42         const char *name;
  43         long ssl_version;
  44 } sslversions[] = {
  45         { "sslv2", CURL_SSLVERSION_SSLv2 },
  46         { "sslv3", CURL_SSLVERSION_SSLv3 },
  47         { "tlsv1", CURL_SSLVERSION_TLSv1 },
  48 #if LIBCURL_VERSION_NUM >= 0x072200
  49         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
  50         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  51         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  52 #endif
  53 };
  54 #if LIBCURL_VERSION_NUM >= 0x070903
  55 static const char *ssl_key;
  56 #endif
  57 #if LIBCURL_VERSION_NUM >= 0x070908
  58 static const char *ssl_capath;
  59 #endif
  60 static const char *ssl_cainfo;
  61 static long curl_low_speed_limit = -1;
  62 static long curl_low_speed_time = -1;
  63 static int curl_ftp_no_epsv;
  64 static const char *curl_http_proxy;
  65 static const char *curl_cookie_file;
  66 static int curl_save_cookies;
  67 struct credential http_auth = CREDENTIAL_INIT;
  68 static int http_proactive_auth;
  69 static const char *user_agent;
  70
  71 #if LIBCURL_VERSION_NUM >= 0x071700
  72 /* Use CURLOPT_KEYPASSWD as is */
  73 #elif LIBCURL_VERSION_NUM >= 0x070903
  74 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  75 #else
  76 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  77 #endif
  78
  79 static struct credential cert_auth = CREDENTIAL_INIT;
  80 static int ssl_cert_password_required;
  81 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  82 static unsigned long http_auth_methods = CURLAUTH_ANY;
  83 #endif
  84
  85 static struct curl_slist *pragma_header;
  86 static struct curl_slist *no_pragma_header;
  87
  88 static struct active_request_slot *active_queue_head;
  89
  90 static char *cached_accept_language;
  91
  92 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
  93 {
  94         size_t size = eltsize * nmemb;
  95         struct buffer *buffer = buffer_;
  96
  97         if (size > buffer->buf.len - buffer->posn)
  98                 size = buffer->buf.len - buffer->posn;
  99         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 100         buffer->posn += size;
 101
 102         return size;
 103 }
 104
 105 #ifndef NO_CURL_IOCTL
 106 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 107 {
 108         struct buffer *buffer = clientp;
 109
 110         switch (cmd) {
 111         case CURLIOCMD_NOP:
 112                 return CURLIOE_OK;
 113
 114         case CURLIOCMD_RESTARTREAD:
 115                 buffer->posn = 0;
 116                 return CURLIOE_OK;
 117
 118         default:
 119                 return CURLIOE_UNKNOWNCMD;
 120         }
 121 }
 122 #endif
 123
 124 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 125 {
 126         size_t size = eltsize * nmemb;
 127         struct strbuf *buffer = buffer_;
 128
 129         strbuf_add(buffer, ptr, size);
 130         return size;
 131 }
 132
 133 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 134 {
 135         return eltsize * nmemb;
 136 }
 137
 138 static void closedown_active_slot(struct active_request_slot *slot)
 139 {
 140         active_requests--;
 141         slot->in_use = 0;
 142 }
 143
 144 static void finish_active_slot(struct active_request_slot *slot)
 145 {
 146         closedown_active_slot(slot);
 147         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 148
 149         if (slot->finished != NULL)
 150                 (*slot->finished) = 1;
 151
 152         /* Store slot results so they can be read after the slot is reused */
 153         if (slot->results != NULL) {
 154                 slot->results->curl_result = slot->curl_result;
 155                 slot->results->http_code = slot->http_code;
 156 #if LIBCURL_VERSION_NUM >= 0x070a08
 157                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 158                                   &slot->results->auth_avail);
 159 #else
 160                 slot->results->auth_avail = 0;
 161 #endif
 162         }
 163
 164         /* Run callback if appropriate */
 165         if (slot->callback_func != NULL)
 166                 slot->callback_func(slot->callback_data);
 167 }
 168
 169 #ifdef USE_CURL_MULTI
 170 static void process_curl_messages(void)
 171 {
 172         int num_messages;
 173         struct active_request_slot *slot;
 174         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 175
 176         while (curl_message != NULL) {
 177                 if (curl_message->msg == CURLMSG_DONE) {
 178                         int curl_result = curl_message->data.result;
 179                         slot = active_queue_head;
 180                         while (slot != NULL &&
 181                                slot->curl != curl_message->easy_handle)
 182                                 slot = slot->next;
 183                         if (slot != NULL) {
 184                                 curl_multi_remove_handle(curlm, slot->curl);
 185                                 slot->curl_result = curl_result;
 186                                 finish_active_slot(slot);
 187                         } else {
 188                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 189                         }
 190                 } else {
 191                         fprintf(stderr, "Unknown CURL message received: %d\n",
 192                                 (int)curl_message->msg);
 193                 }
 194                 curl_message = curl_multi_info_read(curlm, &num_messages);
 195         }
 196 }
 197 #endif
 198
 199 static int http_options(const char *var, const char *value, void *cb)
 200 {
 201         if (!strcmp("http.sslverify", var)) {
 202                 curl_ssl_verify = git_config_bool(var, value);
 203                 return 0;
 204         }
 205         if (!strcmp("http.sslcipherlist", var))
 206                 return git_config_string(&ssl_cipherlist, var, value);
 207         if (!strcmp("http.sslversion", var))
 208                 return git_config_string(&ssl_version, var, value);
 209         if (!strcmp("http.sslcert", var))
 210                 return git_config_string(&ssl_cert, var, value);
 211 #if LIBCURL_VERSION_NUM >= 0x070903
 212         if (!strcmp("http.sslkey", var))
 213                 return git_config_string(&ssl_key, var, value);
 214 #endif
 215 #if LIBCURL_VERSION_NUM >= 0x070908
 216         if (!strcmp("http.sslcapath", var))
 217                 return git_config_string(&ssl_capath, var, value);
 218 #endif
 219         if (!strcmp("http.sslcainfo", var))
 220                 return git_config_string(&ssl_cainfo, var, value);
 221         if (!strcmp("http.sslcertpasswordprotected", var)) {
 222                 ssl_cert_password_required = git_config_bool(var, value);
 223                 return 0;
 224         }
 225         if (!strcmp("http.ssltry", var)) {
 226                 curl_ssl_try = git_config_bool(var, value);
 227                 return 0;
 228         }
 229         if (!strcmp("http.minsessions", var)) {
 230                 min_curl_sessions = git_config_int(var, value);
 231 #ifndef USE_CURL_MULTI
 232                 if (min_curl_sessions > 1)
 233                         min_curl_sessions = 1;
 234 #endif
 235                 return 0;
 236         }
 237 #ifdef USE_CURL_MULTI
 238         if (!strcmp("http.maxrequests", var)) {
 239                 max_requests = git_config_int(var, value);
 240                 return 0;
 241         }
 242 #endif
 243         if (!strcmp("http.lowspeedlimit", var)) {
 244                 curl_low_speed_limit = (long)git_config_int(var, value);
 245                 return 0;
 246         }
 247         if (!strcmp("http.lowspeedtime", var)) {
 248                 curl_low_speed_time = (long)git_config_int(var, value);
 249                 return 0;
 250         }
 251
 252         if (!strcmp("http.noepsv", var)) {
 253                 curl_ftp_no_epsv = git_config_bool(var, value);
 254                 return 0;
 255         }
 256         if (!strcmp("http.proxy", var))
 257                 return git_config_string(&curl_http_proxy, var, value);
 258
 259         if (!strcmp("http.cookiefile", var))
 260                 return git_config_string(&curl_cookie_file, var, value);
 261         if (!strcmp("http.savecookies", var)) {
 262                 curl_save_cookies = git_config_bool(var, value);
 263                 return 0;
 264         }
 265
 266         if (!strcmp("http.postbuffer", var)) {
 267                 http_post_buffer = git_config_int(var, value);
 268                 if (http_post_buffer < LARGE_PACKET_MAX)
 269                         http_post_buffer = LARGE_PACKET_MAX;
 270                 return 0;
 271         }
 272
 273         if (!strcmp("http.useragent", var))
 274                 return git_config_string(&user_agent, var, value);
 275
 276         /* Fall back on the default ones */
 277         return git_default_config(var, value, cb);
 278 }
 279
 280 static void init_curl_http_auth(CURL *result)
 281 {
 282         if (!http_auth.username)
 283                 return;
 284
 285         credential_fill(&http_auth);
 286
 287 #if LIBCURL_VERSION_NUM >= 0x071301
 288         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 289         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 290 #else
 291         {
 292                 static struct strbuf up = STRBUF_INIT;
 293                 /*
 294                  * Note that we assume we only ever have a single set of
 295                  * credentials in a given program run, so we do not have
 296                  * to worry about updating this buffer, only setting its
 297                  * initial value.
 298                  */
 299                 if (!up.len)
 300                         strbuf_addf(&up, "%s:%s",
 301                                 http_auth.username, http_auth.password);
 302                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 303         }
 304 #endif
 305 }
 306
 307 static int has_cert_password(void)
 308 {
 309         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 310                 return 0;
 311         if (!cert_auth.password) {
 312                 cert_auth.protocol = xstrdup("cert");
 313                 cert_auth.username = xstrdup("");
 314                 cert_auth.path = xstrdup(ssl_cert);
 315                 credential_fill(&cert_auth);
 316         }
 317         return 1;
 318 }
 319
 320 #if LIBCURL_VERSION_NUM >= 0x071900
 321 static void set_curl_keepalive(CURL *c)
 322 {
 323         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 324 }
 325
 326 #elif LIBCURL_VERSION_NUM >= 0x071000
 327 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 328 {
 329         int ka = 1;
 330         int rc;
 331         socklen_t len = (socklen_t)sizeof(ka);
 332
 333         if (type != CURLSOCKTYPE_IPCXN)
 334                 return 0;
 335
 336         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 337         if (rc < 0)
 338                 warning("unable to set SO_KEEPALIVE on socket %s",
 339                         strerror(errno));
 340
 341         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 342 }
 343
 344 static void set_curl_keepalive(CURL *c)
 345 {
 346         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 347 }
 348
 349 #else
 350 static void set_curl_keepalive(CURL *c)
 351 {
 352         /* not supported on older curl versions */
 353 }
 354 #endif
 355
 356 static CURL *get_curl_handle(void)
 357 {
 358         CURL *result = curl_easy_init();
 359         long allowed_protocols = 0;
 360
 361         if (!result)
 362                 die("curl_easy_init failed");
 363
 364         if (!curl_ssl_verify) {
 365                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 366                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 367         } else {
 368                 /* Verify authenticity of the peer's certificate */
 369                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 370                 /* The name in the cert must match whom we tried to connect */
 371                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 372         }
 373
 374 #if LIBCURL_VERSION_NUM >= 0x070907
 375         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 376 #endif
 377 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 378         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 379 #endif
 380
 381         if (http_proactive_auth)
 382                 init_curl_http_auth(result);
 383
 384         if (getenv("GIT_SSL_VERSION"))
 385                 ssl_version = getenv("GIT_SSL_VERSION");
 386         if (ssl_version && *ssl_version) {
 387                 int i;
 388                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 389                         if (!strcmp(ssl_version, sslversions[i].name)) {
 390                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 391                                                  sslversions[i].ssl_version);
 392                                 break;
 393                         }
 394                 }
 395                 if (i == ARRAY_SIZE(sslversions))
 396                         warning("unsupported ssl version %s: using default",
 397                                 ssl_version);
 398         }
 399
 400         if (getenv("GIT_SSL_CIPHER_LIST"))
 401                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 402         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 403                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 404                                 ssl_cipherlist);
 405
 406         if (ssl_cert != NULL)
 407                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 408         if (has_cert_password())
 409                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 410 #if LIBCURL_VERSION_NUM >= 0x070903
 411         if (ssl_key != NULL)
 412                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 413 #endif
 414 #if LIBCURL_VERSION_NUM >= 0x070908
 415         if (ssl_capath != NULL)
 416                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 417 #endif
 418         if (ssl_cainfo != NULL)
 419                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 420
 421         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 422                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 423                                  curl_low_speed_limit);
 424                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 425                                  curl_low_speed_time);
 426         }
 427
 428         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 429         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 430 #if LIBCURL_VERSION_NUM >= 0x071301
 431         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 432 #elif LIBCURL_VERSION_NUM >= 0x071101
 433         curl_easy_setopt(result, CURLOPT_POST301, 1);
 434 #endif
 435 #if LIBCURL_VERSION_NUM >= 0x071304
 436         if (is_transport_allowed("http"))
 437                 allowed_protocols |= CURLPROTO_HTTP;
 438         if (is_transport_allowed("https"))
 439                 allowed_protocols |= CURLPROTO_HTTPS;
 440         if (is_transport_allowed("ftp"))
 441                 allowed_protocols |= CURLPROTO_FTP;
 442         if (is_transport_allowed("ftps"))
 443                 allowed_protocols |= CURLPROTO_FTPS;
 444         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 445 #else
 446         if (transport_restrict_protocols())
 447                 warning("protocol restrictions not applied to curl redirects because\n"
 448                         "your curl version is too old (>= 7.19.4)");
 449 #endif
 450
 451         if (getenv("GIT_CURL_VERBOSE"))
 452                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 453
 454         curl_easy_setopt(result, CURLOPT_USERAGENT,
 455                 user_agent ? user_agent : git_user_agent());
 456
 457         if (curl_ftp_no_epsv)
 458                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 459
 460 #ifdef CURLOPT_USE_SSL
 461         if (curl_ssl_try)
 462                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 463 #endif
 464
 465         if (curl_http_proxy) {
 466                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 467         }
 468 #if LIBCURL_VERSION_NUM >= 0x070a07
 469         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 470 #endif
 471
 472         set_curl_keepalive(result);
 473
 474         return result;
 475 }
 476
 477 static void set_from_env(const char **var, const char *envname)
 478 {
 479         const char *val = getenv(envname);
 480         if (val)
 481                 *var = val;
 482 }
 483
 484 void http_init(struct remote *remote, const char *url, int proactive_auth)
 485 {
 486         char *low_speed_limit;
 487         char *low_speed_time;
 488         char *normalized_url;
 489         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 490
 491         config.section = "http";
 492         config.key = NULL;
 493         config.collect_fn = http_options;
 494         config.cascade_fn = git_default_config;
 495         config.cb = NULL;
 496
 497         http_is_verbose = 0;
 498         normalized_url = url_normalize(url, &config.url);
 499
 500         git_config(urlmatch_config_entry, &config);
 501         free(normalized_url);
 502
 503         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 504                 die("curl_global_init failed");
 505
 506         http_proactive_auth = proactive_auth;
 507
 508         if (remote && remote->http_proxy)
 509                 curl_http_proxy = xstrdup(remote->http_proxy);
 510
 511         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 512         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 513
 514 #ifdef USE_CURL_MULTI
 515         {
 516                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 517                 if (http_max_requests != NULL)
 518                         max_requests = atoi(http_max_requests);
 519         }
 520
 521         curlm = curl_multi_init();
 522         if (!curlm)
 523                 die("curl_multi_init failed");
 524 #endif
 525
 526         if (getenv("GIT_SSL_NO_VERIFY"))
 527                 curl_ssl_verify = 0;
 528
 529         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 530 #if LIBCURL_VERSION_NUM >= 0x070903
 531         set_from_env(&ssl_key, "GIT_SSL_KEY");
 532 #endif
 533 #if LIBCURL_VERSION_NUM >= 0x070908
 534         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 535 #endif
 536         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 537
 538         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 539
 540         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 541         if (low_speed_limit != NULL)
 542                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 543         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 544         if (low_speed_time != NULL)
 545                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 546
 547         if (curl_ssl_verify == -1)
 548                 curl_ssl_verify = 1;
 549
 550         curl_session_count = 0;
 551 #ifdef USE_CURL_MULTI
 552         if (max_requests < 1)
 553                 max_requests = DEFAULT_MAX_REQUESTS;
 554 #endif
 555
 556         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 557                 curl_ftp_no_epsv = 1;
 558
 559         if (url) {
 560                 credential_from_url(&http_auth, url);
 561                 if (!ssl_cert_password_required &&
 562                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 563                     starts_with(url, "https://"))
 564                         ssl_cert_password_required = 1;
 565         }
 566
 567 #ifndef NO_CURL_EASY_DUPHANDLE
 568         curl_default = get_curl_handle();
 569 #endif
 570 }
 571
 572 void http_cleanup(void)
 573 {
 574         struct active_request_slot *slot = active_queue_head;
 575
 576         while (slot != NULL) {
 577                 struct active_request_slot *next = slot->next;
 578                 if (slot->curl != NULL) {
 579 #ifdef USE_CURL_MULTI
 580                         curl_multi_remove_handle(curlm, slot->curl);
 581 #endif
 582                         curl_easy_cleanup(slot->curl);
 583                 }
 584                 free(slot);
 585                 slot = next;
 586         }
 587         active_queue_head = NULL;
 588
 589 #ifndef NO_CURL_EASY_DUPHANDLE
 590         curl_easy_cleanup(curl_default);
 591 #endif
 592
 593 #ifdef USE_CURL_MULTI
 594         curl_multi_cleanup(curlm);
 595 #endif
 596         curl_global_cleanup();
 597
 598         curl_slist_free_all(pragma_header);
 599         pragma_header = NULL;
 600
 601         curl_slist_free_all(no_pragma_header);
 602         no_pragma_header = NULL;
 603
 604         if (curl_http_proxy) {
 605                 free((void *)curl_http_proxy);
 606                 curl_http_proxy = NULL;
 607         }
 608
 609         if (cert_auth.password != NULL) {
 610                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 611                 free(cert_auth.password);
 612                 cert_auth.password = NULL;
 613         }
 614         ssl_cert_password_required = 0;
 615
 616         free(cached_accept_language);
 617         cached_accept_language = NULL;
 618 }
 619
 620 struct active_request_slot *get_active_slot(void)
 621 {
 622         struct active_request_slot *slot = active_queue_head;
 623         struct active_request_slot *newslot;
 624
 625 #ifdef USE_CURL_MULTI
 626         int num_transfers;
 627
 628         /* Wait for a slot to open up if the queue is full */
 629         while (active_requests >= max_requests) {
 630                 curl_multi_perform(curlm, &num_transfers);
 631                 if (num_transfers < active_requests)
 632                         process_curl_messages();
 633         }
 634 #endif
 635
 636         while (slot != NULL && slot->in_use)
 637                 slot = slot->next;
 638
 639         if (slot == NULL) {
 640                 newslot = xmalloc(sizeof(*newslot));
 641                 newslot->curl = NULL;
 642                 newslot->in_use = 0;
 643                 newslot->next = NULL;
 644
 645                 slot = active_queue_head;
 646                 if (slot == NULL) {
 647                         active_queue_head = newslot;
 648                 } else {
 649                         while (slot->next != NULL)
 650                                 slot = slot->next;
 651                         slot->next = newslot;
 652                 }
 653                 slot = newslot;
 654         }
 655
 656         if (slot->curl == NULL) {
 657 #ifdef NO_CURL_EASY_DUPHANDLE
 658                 slot->curl = get_curl_handle();
 659 #else
 660                 slot->curl = curl_easy_duphandle(curl_default);
 661 #endif
 662                 curl_session_count++;
 663         }
 664
 665         active_requests++;
 666         slot->in_use = 1;
 667         slot->results = NULL;
 668         slot->finished = NULL;
 669         slot->callback_data = NULL;
 670         slot->callback_func = NULL;
 671         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 672         if (curl_save_cookies)
 673                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 674         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 675         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 676         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 677         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 678         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 679         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 680         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 681         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 682         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 683         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
 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                 xsnprintf(q_format, sizeof(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 static void http_opt_request_remainder(CURL *curl, off_t pos)
1177 {
1178         char buf[128];
1179         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1180         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1181 }
1182
1183 /* http_request() targets */
1184 #define HTTP_REQUEST_STRBUF     0
1185 #define HTTP_REQUEST_FILE       1
1186
1187 static int http_request(const char *url,
1188                         void *result, int target,
1189                         const struct http_get_options *options)
1190 {
1191         struct active_request_slot *slot;
1192         struct slot_results results;
1193         struct curl_slist *headers = NULL;
1194         struct strbuf buf = STRBUF_INIT;
1195         const char *accept_language;
1196         int ret;
1197
1198         slot = get_active_slot();
1199         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1200
1201         if (result == NULL) {
1202                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1203         } else {
1204                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1205                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1206
1207                 if (target == HTTP_REQUEST_FILE) {
1208                         off_t posn = ftello(result);
1209                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1210                                          fwrite);
1211                         if (posn > 0)
1212                                 http_opt_request_remainder(slot->curl, posn);
1213                 } else
1214                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1215                                          fwrite_buffer);
1216         }
1217
1218         accept_language = get_accept_language();
1219
1220         if (accept_language)
1221                 headers = curl_slist_append(headers, accept_language);
1222
1223         strbuf_addstr(&buf, "Pragma:");
1224         if (options && options->no_cache)
1225                 strbuf_addstr(&buf, " no-cache");
1226         if (options && options->keep_error)
1227                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1228
1229         headers = curl_slist_append(headers, buf.buf);
1230
1231         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1232         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1233         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1234
1235         ret = run_one_slot(slot, &results);
1236
1237         if (options && options->content_type) {
1238                 struct strbuf raw = STRBUF_INIT;
1239                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1240                 extract_content_type(&raw, options->content_type,
1241                                      options->charset);
1242                 strbuf_release(&raw);
1243         }
1244
1245         if (options && options->effective_url)
1246                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1247                                 options->effective_url);
1248
1249         curl_slist_free_all(headers);
1250         strbuf_release(&buf);
1251
1252         return ret;
1253 }
1254
1255 /*
1256  * Update the "base" url to a more appropriate value, as deduced by
1257  * redirects seen when requesting a URL starting with "url".
1258  *
1259  * The "asked" parameter is a URL that we asked curl to access, and must begin
1260  * with "base".
1261  *
1262  * The "got" parameter is the URL that curl reported to us as where we ended
1263  * up.
1264  *
1265  * Returns 1 if we updated the base url, 0 otherwise.
1266  *
1267  * Our basic strategy is to compare "base" and "asked" to find the bits
1268  * specific to our request. We then strip those bits off of "got" to yield the
1269  * new base. So for example, if our base is "http://example.com/foo.git",
1270  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1271  * with "https://other.example.com/foo.git/info/refs". We would want the
1272  * new URL to become "https://other.example.com/foo.git".
1273  *
1274  * Note that this assumes a sane redirect scheme. It's entirely possible
1275  * in the example above to end up at a URL that does not even end in
1276  * "info/refs".  In such a case we simply punt, as there is not much we can
1277  * do (and such a scheme is unlikely to represent a real git repository,
1278  * which means we are likely about to abort anyway).
1279  */
1280 static int update_url_from_redirect(struct strbuf *base,
1281                                     const char *asked,
1282                                     const struct strbuf *got)
1283 {
1284         const char *tail;
1285         size_t tail_len;
1286
1287         if (!strcmp(asked, got->buf))
1288                 return 0;
1289
1290         if (!skip_prefix(asked, base->buf, &tail))
1291                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1292                     asked, base->buf);
1293
1294         tail_len = strlen(tail);
1295
1296         if (got->len < tail_len ||
1297             strcmp(tail, got->buf + got->len - tail_len))
1298                 return 0; /* insane redirect scheme */
1299
1300         strbuf_reset(base);
1301         strbuf_add(base, got->buf, got->len - tail_len);
1302         return 1;
1303 }
1304
1305 static int http_request_reauth(const char *url,
1306                                void *result, int target,
1307                                struct http_get_options *options)
1308 {
1309         int ret = http_request(url, result, target, options);
1310
1311         if (options && options->effective_url && options->base_url) {
1312                 if (update_url_from_redirect(options->base_url,
1313                                              url, options->effective_url)) {
1314                         credential_from_url(&http_auth, options->base_url->buf);
1315                         url = options->effective_url->buf;
1316                 }
1317         }
1318
1319         if (ret != HTTP_REAUTH)
1320                 return ret;
1321
1322         /*
1323          * If we are using KEEP_ERROR, the previous request may have
1324          * put cruft into our output stream; we should clear it out before
1325          * making our next request. We only know how to do this for
1326          * the strbuf case, but that is enough to satisfy current callers.
1327          */
1328         if (options && options->keep_error) {
1329                 switch (target) {
1330                 case HTTP_REQUEST_STRBUF:
1331                         strbuf_reset(result);
1332                         break;
1333                 default:
1334                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1335                 }
1336         }
1337
1338         credential_fill(&http_auth);
1339
1340         return http_request(url, result, target, options);
1341 }
1342
1343 int http_get_strbuf(const char *url,
1344                     struct strbuf *result,
1345                     struct http_get_options *options)
1346 {
1347         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1348 }
1349
1350 /*
1351  * Downloads a URL and stores the result in the given file.
1352  *
1353  * If a previous interrupted download is detected (i.e. a previous temporary
1354  * file is still around) the download is resumed.
1355  */
1356 static int http_get_file(const char *url, const char *filename,
1357                          struct http_get_options *options)
1358 {
1359         int ret;
1360         struct strbuf tmpfile = STRBUF_INIT;
1361         FILE *result;
1362
1363         strbuf_addf(&tmpfile, "%s.temp", filename);
1364         result = fopen(tmpfile.buf, "a");
1365         if (!result) {
1366                 error("Unable to open local file %s", tmpfile.buf);
1367                 ret = HTTP_ERROR;
1368                 goto cleanup;
1369         }
1370
1371         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1372         fclose(result);
1373
1374         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1375                 ret = HTTP_ERROR;
1376 cleanup:
1377         strbuf_release(&tmpfile);
1378         return ret;
1379 }
1380
1381 int http_fetch_ref(const char *base, struct ref *ref)
1382 {
1383         struct http_get_options options = {0};
1384         char *url;
1385         struct strbuf buffer = STRBUF_INIT;
1386         int ret = -1;
1387
1388         options.no_cache = 1;
1389
1390         url = quote_ref_url(base, ref->name);
1391         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1392                 strbuf_rtrim(&buffer);
1393                 if (buffer.len == 40)
1394                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1395                 else if (starts_with(buffer.buf, "ref: ")) {
1396                         ref->symref = xstrdup(buffer.buf + 5);
1397                         ret = 0;
1398                 }
1399         }
1400
1401         strbuf_release(&buffer);
1402         free(url);
1403         return ret;
1404 }
1405
1406 /* Helpers for fetching packs */
1407 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1408 {
1409         char *url, *tmp;
1410         struct strbuf buf = STRBUF_INIT;
1411
1412         if (http_is_verbose)
1413                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1414
1415         end_url_with_slash(&buf, base_url);
1416         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1417         url = strbuf_detach(&buf, NULL);
1418
1419         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1420         tmp = strbuf_detach(&buf, NULL);
1421
1422         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1423                 error("Unable to get pack index %s", url);
1424                 free(tmp);
1425                 tmp = NULL;
1426         }
1427
1428         free(url);
1429         return tmp;
1430 }
1431
1432 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1433         unsigned char *sha1, const char *base_url)
1434 {
1435         struct packed_git *new_pack;
1436         char *tmp_idx = NULL;
1437         int ret;
1438
1439         if (has_pack_index(sha1)) {
1440                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1441                 if (!new_pack)
1442                         return -1; /* parse_pack_index() already issued error message */
1443                 goto add_pack;
1444         }
1445
1446         tmp_idx = fetch_pack_index(sha1, base_url);
1447         if (!tmp_idx)
1448                 return -1;
1449
1450         new_pack = parse_pack_index(sha1, tmp_idx);
1451         if (!new_pack) {
1452                 unlink(tmp_idx);
1453                 free(tmp_idx);
1454
1455                 return -1; /* parse_pack_index() already issued error message */
1456         }
1457
1458         ret = verify_pack_index(new_pack);
1459         if (!ret) {
1460                 close_pack_index(new_pack);
1461                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1462         }
1463         free(tmp_idx);
1464         if (ret)
1465                 return -1;
1466
1467 add_pack:
1468         new_pack->next = *packs_head;
1469         *packs_head = new_pack;
1470         return 0;
1471 }
1472
1473 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1474 {
1475         struct http_get_options options = {0};
1476         int ret = 0, i = 0;
1477         char *url, *data;
1478         struct strbuf buf = STRBUF_INIT;
1479         unsigned char sha1[20];
1480
1481         end_url_with_slash(&buf, base_url);
1482         strbuf_addstr(&buf, "objects/info/packs");
1483         url = strbuf_detach(&buf, NULL);
1484
1485         options.no_cache = 1;
1486         ret = http_get_strbuf(url, &buf, &options);
1487         if (ret != HTTP_OK)
1488                 goto cleanup;
1489
1490         data = buf.buf;
1491         while (i < buf.len) {
1492                 switch (data[i]) {
1493                 case 'P':
1494                         i++;
1495                         if (i + 52 <= buf.len &&
1496                             starts_with(data + i, " pack-") &&
1497                             starts_with(data + i + 46, ".pack\n")) {
1498                                 get_sha1_hex(data + i + 6, sha1);
1499                                 fetch_and_setup_pack_index(packs_head, sha1,
1500                                                       base_url);
1501                                 i += 51;
1502                                 break;
1503                         }
1504                 default:
1505                         while (i < buf.len && data[i] != '\n')
1506                                 i++;
1507                 }
1508                 i++;
1509         }
1510
1511 cleanup:
1512         free(url);
1513         return ret;
1514 }
1515
1516 void release_http_pack_request(struct http_pack_request *preq)
1517 {
1518         if (preq->packfile != NULL) {
1519                 fclose(preq->packfile);
1520                 preq->packfile = 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         size_t len;
1533         struct child_process ip = CHILD_PROCESS_INIT;
1534         const char *ip_argv[8];
1535
1536         close_pack_index(p);
1537
1538         fclose(preq->packfile);
1539         preq->packfile = NULL;
1540
1541         lst = preq->lst;
1542         while (*lst != p)
1543                 lst = &((*lst)->next);
1544         *lst = (*lst)->next;
1545
1546         if (!strip_suffix(preq->tmpfile, ".pack.temp", &len))
1547                 die("BUG: pack tmpfile does not end in .pack.temp?");
1548         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
1549
1550         ip_argv[0] = "index-pack";
1551         ip_argv[1] = "-o";
1552         ip_argv[2] = tmp_idx;
1553         ip_argv[3] = preq->tmpfile;
1554         ip_argv[4] = NULL;
1555
1556         ip.argv = ip_argv;
1557         ip.git_cmd = 1;
1558         ip.no_stdin = 1;
1559         ip.no_stdout = 1;
1560
1561         if (run_command(&ip)) {
1562                 unlink(preq->tmpfile);
1563                 unlink(tmp_idx);
1564                 free(tmp_idx);
1565                 return -1;
1566         }
1567
1568         unlink(sha1_pack_index_name(p->sha1));
1569
1570         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1571          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1572                 free(tmp_idx);
1573                 return -1;
1574         }
1575
1576         install_packed_git(p);
1577         free(tmp_idx);
1578         return 0;
1579 }
1580
1581 struct http_pack_request *new_http_pack_request(
1582         struct packed_git *target, const char *base_url)
1583 {
1584         off_t prev_posn = 0;
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 = ftello(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                 http_opt_request_remainder(preq->slot->curl, prev_posn);
1623         }
1624
1625         return preq;
1626
1627 abort:
1628         free(preq->url);
1629         free(preq);
1630         return NULL;
1631 }
1632
1633 /* Helpers for fetching objects (loose) */
1634 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1635                                void *data)
1636 {
1637         unsigned char expn[4096];
1638         size_t size = eltsize * nmemb;
1639         int posn = 0;
1640         struct http_object_request *freq =
1641                 (struct http_object_request *)data;
1642         do {
1643                 ssize_t retval = xwrite(freq->localfile,
1644                                         (char *) ptr + posn, size - posn);
1645                 if (retval < 0)
1646                         return posn;
1647                 posn += retval;
1648         } while (posn < size);
1649
1650         freq->stream.avail_in = size;
1651         freq->stream.next_in = (void *)ptr;
1652         do {
1653                 freq->stream.next_out = expn;
1654                 freq->stream.avail_out = sizeof(expn);
1655                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1656                 git_SHA1_Update(&freq->c, expn,
1657                                 sizeof(expn) - freq->stream.avail_out);
1658         } while (freq->stream.avail_in && freq->zret == Z_OK);
1659         return size;
1660 }
1661
1662 struct http_object_request *new_http_object_request(const char *base_url,
1663         unsigned char *sha1)
1664 {
1665         char *hex = sha1_to_hex(sha1);
1666         const char *filename;
1667         char prevfile[PATH_MAX];
1668         int prevlocal;
1669         char prev_buf[PREV_BUF_SIZE];
1670         ssize_t prev_read = 0;
1671         off_t prev_posn = 0;
1672         struct http_object_request *freq;
1673
1674         freq = xcalloc(1, sizeof(*freq));
1675         hashcpy(freq->sha1, sha1);
1676         freq->localfile = -1;
1677
1678         filename = sha1_file_name(sha1);
1679         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1680                  "%s.temp", filename);
1681
1682         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1683         unlink_or_warn(prevfile);
1684         rename(freq->tmpfile, prevfile);
1685         unlink_or_warn(freq->tmpfile);
1686
1687         if (freq->localfile != -1)
1688                 error("fd leakage in start: %d", freq->localfile);
1689         freq->localfile = open(freq->tmpfile,
1690                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1691         /*
1692          * This could have failed due to the "lazy directory creation";
1693          * try to mkdir the last path component.
1694          */
1695         if (freq->localfile < 0 && errno == ENOENT) {
1696                 char *dir = strrchr(freq->tmpfile, '/');
1697                 if (dir) {
1698                         *dir = 0;
1699                         mkdir(freq->tmpfile, 0777);
1700                         *dir = '/';
1701                 }
1702                 freq->localfile = open(freq->tmpfile,
1703                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1704         }
1705
1706         if (freq->localfile < 0) {
1707                 error("Couldn't create temporary file %s: %s",
1708                       freq->tmpfile, strerror(errno));
1709                 goto abort;
1710         }
1711
1712         git_inflate_init(&freq->stream);
1713
1714         git_SHA1_Init(&freq->c);
1715
1716         freq->url = get_remote_object_url(base_url, hex, 0);
1717
1718         /*
1719          * If a previous temp file is present, process what was already
1720          * fetched.
1721          */
1722         prevlocal = open(prevfile, O_RDONLY);
1723         if (prevlocal != -1) {
1724                 do {
1725                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1726                         if (prev_read>0) {
1727                                 if (fwrite_sha1_file(prev_buf,
1728                                                      1,
1729                                                      prev_read,
1730                                                      freq) == prev_read) {
1731                                         prev_posn += prev_read;
1732                                 } else {
1733                                         prev_read = -1;
1734                                 }
1735                         }
1736                 } while (prev_read > 0);
1737                 close(prevlocal);
1738         }
1739         unlink_or_warn(prevfile);
1740
1741         /*
1742          * Reset inflate/SHA1 if there was an error reading the previous temp
1743          * file; also rewind to the beginning of the local file.
1744          */
1745         if (prev_read == -1) {
1746                 memset(&freq->stream, 0, sizeof(freq->stream));
1747                 git_inflate_init(&freq->stream);
1748                 git_SHA1_Init(&freq->c);
1749                 if (prev_posn>0) {
1750                         prev_posn = 0;
1751                         lseek(freq->localfile, 0, SEEK_SET);
1752                         if (ftruncate(freq->localfile, 0) < 0) {
1753                                 error("Couldn't truncate temporary file %s: %s",
1754                                           freq->tmpfile, strerror(errno));
1755                                 goto abort;
1756                         }
1757                 }
1758         }
1759
1760         freq->slot = get_active_slot();
1761
1762         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1763         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1764         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1765         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1766         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1767
1768         /*
1769          * If we have successfully processed data from a previous fetch
1770          * attempt, only fetch the data we don't already have.
1771          */
1772         if (prev_posn>0) {
1773                 if (http_is_verbose)
1774                         fprintf(stderr,
1775                                 "Resuming fetch of object %s at byte %ld\n",
1776                                 hex, prev_posn);
1777                 http_opt_request_remainder(freq->slot->curl, prev_posn);
1778         }
1779
1780         return freq;
1781
1782 abort:
1783         free(freq->url);
1784         free(freq);
1785         return NULL;
1786 }
1787
1788 void process_http_object_request(struct http_object_request *freq)
1789 {
1790         if (freq->slot == NULL)
1791                 return;
1792         freq->curl_result = freq->slot->curl_result;
1793         freq->http_code = freq->slot->http_code;
1794         freq->slot = NULL;
1795 }
1796
1797 int finish_http_object_request(struct http_object_request *freq)
1798 {
1799         struct stat st;
1800
1801         close(freq->localfile);
1802         freq->localfile = -1;
1803
1804         process_http_object_request(freq);
1805
1806         if (freq->http_code == 416) {
1807                 warning("requested range invalid; we may already have all the data.");
1808         } else if (freq->curl_result != CURLE_OK) {
1809                 if (stat(freq->tmpfile, &st) == 0)
1810                         if (st.st_size == 0)
1811                                 unlink_or_warn(freq->tmpfile);
1812                 return -1;
1813         }
1814
1815         git_inflate_end(&freq->stream);
1816         git_SHA1_Final(freq->real_sha1, &freq->c);
1817         if (freq->zret != Z_STREAM_END) {
1818                 unlink_or_warn(freq->tmpfile);
1819                 return -1;
1820         }
1821         if (hashcmp(freq->sha1, freq->real_sha1)) {
1822                 unlink_or_warn(freq->tmpfile);
1823                 return -1;
1824         }
1825         freq->rename =
1826                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
1827
1828         return freq->rename;
1829 }
1830
1831 void abort_http_object_request(struct http_object_request *freq)
1832 {
1833         unlink_or_warn(freq->tmpfile);
1834
1835         release_http_object_request(freq);
1836 }
1837
1838 void release_http_object_request(struct http_object_request *freq)
1839 {
1840         if (freq->localfile != -1) {
1841                 close(freq->localfile);
1842                 freq->localfile = -1;
1843         }
1844         if (freq->url != NULL) {
1845                 free(freq->url);
1846                 freq->url = NULL;
1847         }
1848         if (freq->slot != NULL) {
1849                 freq->slot->callback_func = NULL;
1850                 freq->slot->callback_data = NULL;
1851                 release_active_slot(freq->slot);
1852                 freq->slot = NULL;
1853         }
1854 }