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_pathname(&ssl_capath, var, value);
 219 #endif
 220         if (!strcmp("http.sslcainfo", var))
 221                 return git_config_pathname(&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 #if LIBCURL_VERSION_NUM >= 0x071800
 469                 if (starts_with(curl_http_proxy, "socks5h"))
 470                         curl_easy_setopt(result,
 471                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
 472                 else if (starts_with(curl_http_proxy, "socks5"))
 473                         curl_easy_setopt(result,
 474                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
 475                 else if (starts_with(curl_http_proxy, "socks4a"))
 476                         curl_easy_setopt(result,
 477                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
 478                 else if (starts_with(curl_http_proxy, "socks"))
 479                         curl_easy_setopt(result,
 480                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
 481 #endif
 482         }
 483 #if LIBCURL_VERSION_NUM >= 0x070a07
 484         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 485 #endif
 486
 487         set_curl_keepalive(result);
 488
 489         return result;
 490 }
 491
 492 static void set_from_env(const char **var, const char *envname)
 493 {
 494         const char *val = getenv(envname);
 495         if (val)
 496                 *var = val;
 497 }
 498
 499 void http_init(struct remote *remote, const char *url, int proactive_auth)
 500 {
 501         char *low_speed_limit;
 502         char *low_speed_time;
 503         char *normalized_url;
 504         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 505
 506         config.section = "http";
 507         config.key = NULL;
 508         config.collect_fn = http_options;
 509         config.cascade_fn = git_default_config;
 510         config.cb = NULL;
 511
 512         http_is_verbose = 0;
 513         normalized_url = url_normalize(url, &config.url);
 514
 515         git_config(urlmatch_config_entry, &config);
 516         free(normalized_url);
 517
 518         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 519                 die("curl_global_init failed");
 520
 521         http_proactive_auth = proactive_auth;
 522
 523         if (remote && remote->http_proxy)
 524                 curl_http_proxy = xstrdup(remote->http_proxy);
 525
 526         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 527         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 528
 529 #ifdef USE_CURL_MULTI
 530         {
 531                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 532                 if (http_max_requests != NULL)
 533                         max_requests = atoi(http_max_requests);
 534         }
 535
 536         curlm = curl_multi_init();
 537         if (!curlm)
 538                 die("curl_multi_init failed");
 539 #endif
 540
 541         if (getenv("GIT_SSL_NO_VERIFY"))
 542                 curl_ssl_verify = 0;
 543
 544         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 545 #if LIBCURL_VERSION_NUM >= 0x070903
 546         set_from_env(&ssl_key, "GIT_SSL_KEY");
 547 #endif
 548 #if LIBCURL_VERSION_NUM >= 0x070908
 549         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 550 #endif
 551         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 552
 553         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 554
 555         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 556         if (low_speed_limit != NULL)
 557                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 558         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 559         if (low_speed_time != NULL)
 560                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 561
 562         if (curl_ssl_verify == -1)
 563                 curl_ssl_verify = 1;
 564
 565         curl_session_count = 0;
 566 #ifdef USE_CURL_MULTI
 567         if (max_requests < 1)
 568                 max_requests = DEFAULT_MAX_REQUESTS;
 569 #endif
 570
 571         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 572                 curl_ftp_no_epsv = 1;
 573
 574         if (url) {
 575                 credential_from_url(&http_auth, url);
 576                 if (!ssl_cert_password_required &&
 577                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 578                     starts_with(url, "https://"))
 579                         ssl_cert_password_required = 1;
 580         }
 581
 582 #ifndef NO_CURL_EASY_DUPHANDLE
 583         curl_default = get_curl_handle();
 584 #endif
 585 }
 586
 587 void http_cleanup(void)
 588 {
 589         struct active_request_slot *slot = active_queue_head;
 590
 591         while (slot != NULL) {
 592                 struct active_request_slot *next = slot->next;
 593                 if (slot->curl != NULL) {
 594 #ifdef USE_CURL_MULTI
 595                         curl_multi_remove_handle(curlm, slot->curl);
 596 #endif
 597                         curl_easy_cleanup(slot->curl);
 598                 }
 599                 free(slot);
 600                 slot = next;
 601         }
 602         active_queue_head = NULL;
 603
 604 #ifndef NO_CURL_EASY_DUPHANDLE
 605         curl_easy_cleanup(curl_default);
 606 #endif
 607
 608 #ifdef USE_CURL_MULTI
 609         curl_multi_cleanup(curlm);
 610 #endif
 611         curl_global_cleanup();
 612
 613         curl_slist_free_all(pragma_header);
 614         pragma_header = NULL;
 615
 616         curl_slist_free_all(no_pragma_header);
 617         no_pragma_header = NULL;
 618
 619         if (curl_http_proxy) {
 620                 free((void *)curl_http_proxy);
 621                 curl_http_proxy = NULL;
 622         }
 623
 624         if (cert_auth.password != NULL) {
 625                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 626                 free(cert_auth.password);
 627                 cert_auth.password = NULL;
 628         }
 629         ssl_cert_password_required = 0;
 630
 631         free(cached_accept_language);
 632         cached_accept_language = NULL;
 633 }
 634
 635 struct active_request_slot *get_active_slot(void)
 636 {
 637         struct active_request_slot *slot = active_queue_head;
 638         struct active_request_slot *newslot;
 639
 640 #ifdef USE_CURL_MULTI
 641         int num_transfers;
 642
 643         /* Wait for a slot to open up if the queue is full */
 644         while (active_requests >= max_requests) {
 645                 curl_multi_perform(curlm, &num_transfers);
 646                 if (num_transfers < active_requests)
 647                         process_curl_messages();
 648         }
 649 #endif
 650
 651         while (slot != NULL && slot->in_use)
 652                 slot = slot->next;
 653
 654         if (slot == NULL) {
 655                 newslot = xmalloc(sizeof(*newslot));
 656                 newslot->curl = NULL;
 657                 newslot->in_use = 0;
 658                 newslot->next = NULL;
 659
 660                 slot = active_queue_head;
 661                 if (slot == NULL) {
 662                         active_queue_head = newslot;
 663                 } else {
 664                         while (slot->next != NULL)
 665                                 slot = slot->next;
 666                         slot->next = newslot;
 667                 }
 668                 slot = newslot;
 669         }
 670
 671         if (slot->curl == NULL) {
 672 #ifdef NO_CURL_EASY_DUPHANDLE
 673                 slot->curl = get_curl_handle();
 674 #else
 675                 slot->curl = curl_easy_duphandle(curl_default);
 676 #endif
 677                 curl_session_count++;
 678         }
 679
 680         active_requests++;
 681         slot->in_use = 1;
 682         slot->results = NULL;
 683         slot->finished = NULL;
 684         slot->callback_data = NULL;
 685         slot->callback_func = NULL;
 686         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 687         if (curl_save_cookies)
 688                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 689         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 690         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 691         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 692         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 693         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 694         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 695         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 696         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 697         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 698 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 699         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 700 #endif
 701         if (http_auth.password)
 702                 init_curl_http_auth(slot->curl);
 703
 704         return slot;
 705 }
 706
 707 int start_active_slot(struct active_request_slot *slot)
 708 {
 709 #ifdef USE_CURL_MULTI
 710         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 711         int num_transfers;
 712
 713         if (curlm_result != CURLM_OK &&
 714             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 715                 active_requests--;
 716                 slot->in_use = 0;
 717                 return 0;
 718         }
 719
 720         /*
 721          * We know there must be something to do, since we just added
 722          * something.
 723          */
 724         curl_multi_perform(curlm, &num_transfers);
 725 #endif
 726         return 1;
 727 }
 728
 729 #ifdef USE_CURL_MULTI
 730 struct fill_chain {
 731         void *data;
 732         int (*fill)(void *);
 733         struct fill_chain *next;
 734 };
 735
 736 static struct fill_chain *fill_cfg;
 737
 738 void add_fill_function(void *data, int (*fill)(void *))
 739 {
 740         struct fill_chain *new = xmalloc(sizeof(*new));
 741         struct fill_chain **linkp = &fill_cfg;
 742         new->data = data;
 743         new->fill = fill;
 744         new->next = NULL;
 745         while (*linkp)
 746                 linkp = &(*linkp)->next;
 747         *linkp = new;
 748 }
 749
 750 void fill_active_slots(void)
 751 {
 752         struct active_request_slot *slot = active_queue_head;
 753
 754         while (active_requests < max_requests) {
 755                 struct fill_chain *fill;
 756                 for (fill = fill_cfg; fill; fill = fill->next)
 757                         if (fill->fill(fill->data))
 758                                 break;
 759
 760                 if (!fill)
 761                         break;
 762         }
 763
 764         while (slot != NULL) {
 765                 if (!slot->in_use && slot->curl != NULL
 766                         && curl_session_count > min_curl_sessions) {
 767                         curl_easy_cleanup(slot->curl);
 768                         slot->curl = NULL;
 769                         curl_session_count--;
 770                 }
 771                 slot = slot->next;
 772         }
 773 }
 774
 775 void step_active_slots(void)
 776 {
 777         int num_transfers;
 778         CURLMcode curlm_result;
 779
 780         do {
 781                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 782         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 783         if (num_transfers < active_requests) {
 784                 process_curl_messages();
 785                 fill_active_slots();
 786         }
 787 }
 788 #endif
 789
 790 void run_active_slot(struct active_request_slot *slot)
 791 {
 792 #ifdef USE_CURL_MULTI
 793         fd_set readfds;
 794         fd_set writefds;
 795         fd_set excfds;
 796         int max_fd;
 797         struct timeval select_timeout;
 798         int finished = 0;
 799
 800         slot->finished = &finished;
 801         while (!finished) {
 802                 step_active_slots();
 803
 804                 if (slot->in_use) {
 805 #if LIBCURL_VERSION_NUM >= 0x070f04
 806                         long curl_timeout;
 807                         curl_multi_timeout(curlm, &curl_timeout);
 808                         if (curl_timeout == 0) {
 809                                 continue;
 810                         } else if (curl_timeout == -1) {
 811                                 select_timeout.tv_sec  = 0;
 812                                 select_timeout.tv_usec = 50000;
 813                         } else {
 814                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 815                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 816                         }
 817 #else
 818                         select_timeout.tv_sec  = 0;
 819                         select_timeout.tv_usec = 50000;
 820 #endif
 821
 822                         max_fd = -1;
 823                         FD_ZERO(&readfds);
 824                         FD_ZERO(&writefds);
 825                         FD_ZERO(&excfds);
 826                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 827
 828                         /*
 829                          * It can happen that curl_multi_timeout returns a pathologically
 830                          * long timeout when curl_multi_fdset returns no file descriptors
 831                          * to read.  See commit message for more details.
 832                          */
 833                         if (max_fd < 0 &&
 834                             (select_timeout.tv_sec > 0 ||
 835                              select_timeout.tv_usec > 50000)) {
 836                                 select_timeout.tv_sec  = 0;
 837                                 select_timeout.tv_usec = 50000;
 838                         }
 839
 840                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 841                 }
 842         }
 843 #else
 844         while (slot->in_use) {
 845                 slot->curl_result = curl_easy_perform(slot->curl);
 846                 finish_active_slot(slot);
 847         }
 848 #endif
 849 }
 850
 851 static void release_active_slot(struct active_request_slot *slot)
 852 {
 853         closedown_active_slot(slot);
 854         if (slot->curl && curl_session_count > min_curl_sessions) {
 855 #ifdef USE_CURL_MULTI
 856                 curl_multi_remove_handle(curlm, slot->curl);
 857 #endif
 858                 curl_easy_cleanup(slot->curl);
 859                 slot->curl = NULL;
 860                 curl_session_count--;
 861         }
 862 #ifdef USE_CURL_MULTI
 863         fill_active_slots();
 864 #endif
 865 }
 866
 867 void finish_all_active_slots(void)
 868 {
 869         struct active_request_slot *slot = active_queue_head;
 870
 871         while (slot != NULL)
 872                 if (slot->in_use) {
 873                         run_active_slot(slot);
 874                         slot = active_queue_head;
 875                 } else {
 876                         slot = slot->next;
 877                 }
 878 }
 879
 880 /* Helpers for modifying and creating URLs */
 881 static inline int needs_quote(int ch)
 882 {
 883         if (((ch >= 'A') && (ch <= 'Z'))
 884                         || ((ch >= 'a') && (ch <= 'z'))
 885                         || ((ch >= '0') && (ch <= '9'))
 886                         || (ch == '/')
 887                         || (ch == '-')
 888                         || (ch == '.'))
 889                 return 0;
 890         return 1;
 891 }
 892
 893 static char *quote_ref_url(const char *base, const char *ref)
 894 {
 895         struct strbuf buf = STRBUF_INIT;
 896         const char *cp;
 897         int ch;
 898
 899         end_url_with_slash(&buf, base);
 900
 901         for (cp = ref; (ch = *cp) != 0; cp++)
 902                 if (needs_quote(ch))
 903                         strbuf_addf(&buf, "%%%02x", ch);
 904                 else
 905                         strbuf_addch(&buf, *cp);
 906
 907         return strbuf_detach(&buf, NULL);
 908 }
 909
 910 void append_remote_object_url(struct strbuf *buf, const char *url,
 911                               const char *hex,
 912                               int only_two_digit_prefix)
 913 {
 914         end_url_with_slash(buf, url);
 915
 916         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 917         if (!only_two_digit_prefix)
 918                 strbuf_addf(buf, "%s", hex+2);
 919 }
 920
 921 char *get_remote_object_url(const char *url, const char *hex,
 922                             int only_two_digit_prefix)
 923 {
 924         struct strbuf buf = STRBUF_INIT;
 925         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 926         return strbuf_detach(&buf, NULL);
 927 }
 928
 929 static int handle_curl_result(struct slot_results *results)
 930 {
 931         /*
 932          * If we see a failing http code with CURLE_OK, we have turned off
 933          * FAILONERROR (to keep the server's custom error response), and should
 934          * translate the code into failure here.
 935          */
 936         if (results->curl_result == CURLE_OK &&
 937             results->http_code >= 400) {
 938                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 939                 /*
 940                  * Normally curl will already have put the "reason phrase"
 941                  * from the server into curl_errorstr; unfortunately without
 942                  * FAILONERROR it is lost, so we can give only the numeric
 943                  * status code.
 944                  */
 945                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 946                          "The requested URL returned error: %ld",
 947                          results->http_code);
 948         }
 949
 950         if (results->curl_result == CURLE_OK) {
 951                 credential_approve(&http_auth);
 952                 return HTTP_OK;
 953         } else if (missing_target(results))
 954                 return HTTP_MISSING_TARGET;
 955         else if (results->http_code == 401) {
 956                 if (http_auth.username && http_auth.password) {
 957                         credential_reject(&http_auth);
 958                         return HTTP_NOAUTH;
 959                 } else {
 960 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 961                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
 962 #endif
 963                         return HTTP_REAUTH;
 964                 }
 965         } else {
 966 #if LIBCURL_VERSION_NUM >= 0x070c00
 967                 if (!curl_errorstr[0])
 968                         strlcpy(curl_errorstr,
 969                                 curl_easy_strerror(results->curl_result),
 970                                 sizeof(curl_errorstr));
 971 #endif
 972                 return HTTP_ERROR;
 973         }
 974 }
 975
 976 int run_one_slot(struct active_request_slot *slot,
 977                  struct slot_results *results)
 978 {
 979         slot->results = results;
 980         if (!start_active_slot(slot)) {
 981                 snprintf(curl_errorstr, sizeof(curl_errorstr),
 982                          "failed to start HTTP request");
 983                 return HTTP_START_FAILED;
 984         }
 985
 986         run_active_slot(slot);
 987         return handle_curl_result(results);
 988 }
 989
 990 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
 991 {
 992         char *ptr;
 993         CURLcode ret;
 994
 995         strbuf_reset(buf);
 996         ret = curl_easy_getinfo(curl, info, &ptr);
 997         if (!ret && ptr)
 998                 strbuf_addstr(buf, ptr);
 999         return ret;
1000 }
1001
1002 /*
1003  * Check for and extract a content-type parameter. "raw"
1004  * should be positioned at the start of the potential
1005  * parameter, with any whitespace already removed.
1006  *
1007  * "name" is the name of the parameter. The value is appended
1008  * to "out".
1009  */
1010 static int extract_param(const char *raw, const char *name,
1011                          struct strbuf *out)
1012 {
1013         size_t len = strlen(name);
1014
1015         if (strncasecmp(raw, name, len))
1016                 return -1;
1017         raw += len;
1018
1019         if (*raw != '=')
1020                 return -1;
1021         raw++;
1022
1023         while (*raw && !isspace(*raw) && *raw != ';')
1024                 strbuf_addch(out, *raw++);
1025         return 0;
1026 }
1027
1028 /*
1029  * Extract a normalized version of the content type, with any
1030  * spaces suppressed, all letters lowercased, and no trailing ";"
1031  * or parameters.
1032  *
1033  * Note that we will silently remove even invalid whitespace. For
1034  * example, "text / plain" is specifically forbidden by RFC 2616,
1035  * but "text/plain" is the only reasonable output, and this keeps
1036  * our code simple.
1037  *
1038  * If the "charset" argument is not NULL, store the value of any
1039  * charset parameter there.
1040  *
1041  * Example:
1042  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1043  *   "text / plain" -> "text/plain"
1044  */
1045 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1046                                  struct strbuf *charset)
1047 {
1048         const char *p;
1049
1050         strbuf_reset(type);
1051         strbuf_grow(type, raw->len);
1052         for (p = raw->buf; *p; p++) {
1053                 if (isspace(*p))
1054                         continue;
1055                 if (*p == ';') {
1056                         p++;
1057                         break;
1058                 }
1059                 strbuf_addch(type, tolower(*p));
1060         }
1061
1062         if (!charset)
1063                 return;
1064
1065         strbuf_reset(charset);
1066         while (*p) {
1067                 while (isspace(*p) || *p == ';')
1068                         p++;
1069                 if (!extract_param(p, "charset", charset))
1070                         return;
1071                 while (*p && !isspace(*p))
1072                         p++;
1073         }
1074
1075         if (!charset->len && starts_with(type->buf, "text/"))
1076                 strbuf_addstr(charset, "ISO-8859-1");
1077 }
1078
1079 static void write_accept_language(struct strbuf *buf)
1080 {
1081         /*
1082          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1083          * that, q-value will be smaller than 0.001, the minimum q-value the
1084          * HTTP specification allows. See
1085          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1086          */
1087         const int MAX_DECIMAL_PLACES = 3;
1088         const int MAX_LANGUAGE_TAGS = 1000;
1089         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1090         char **language_tags = NULL;
1091         int num_langs = 0;
1092         const char *s = get_preferred_languages();
1093         int i;
1094         struct strbuf tag = STRBUF_INIT;
1095
1096         /* Don't add Accept-Language header if no language is preferred. */
1097         if (!s)
1098                 return;
1099
1100         /*
1101          * Split the colon-separated string of preferred languages into
1102          * language_tags array.
1103          */
1104         do {
1105                 /* collect language tag */
1106                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1107                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1108
1109                 /* skip .codeset, @modifier and any other unnecessary parts */
1110                 while (*s && *s != ':')
1111                         s++;
1112
1113                 if (tag.len) {
1114                         num_langs++;
1115                         REALLOC_ARRAY(language_tags, num_langs);
1116                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1117                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1118                                 break;
1119                 }
1120         } while (*s++);
1121
1122         /* write Accept-Language header into buf */
1123         if (num_langs) {
1124                 int last_buf_len = 0;
1125                 int max_q;
1126                 int decimal_places;
1127                 char q_format[32];
1128
1129                 /* add '*' */
1130                 REALLOC_ARRAY(language_tags, num_langs + 1);
1131                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1132
1133                 /* compute decimal_places */
1134                 for (max_q = 1, decimal_places = 0;
1135                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1136                      decimal_places++, max_q *= 10)
1137                         ;
1138
1139                 sprintf(q_format, ";q=0.%%0%dd", decimal_places);
1140
1141                 strbuf_addstr(buf, "Accept-Language: ");
1142
1143                 for (i = 0; i < num_langs; i++) {
1144                         if (i > 0)
1145                                 strbuf_addstr(buf, ", ");
1146
1147                         strbuf_addstr(buf, language_tags[i]);
1148
1149                         if (i > 0)
1150                                 strbuf_addf(buf, q_format, max_q - i);
1151
1152                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1153                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1154                                 break;
1155                         }
1156
1157                         last_buf_len = buf->len;
1158                 }
1159         }
1160
1161         /* free language tags -- last one is a static '*' */
1162         for (i = 0; i < num_langs - 1; i++)
1163                 free(language_tags[i]);
1164         free(language_tags);
1165 }
1166
1167 /*
1168  * Get an Accept-Language header which indicates user's preferred languages.
1169  *
1170  * Examples:
1171  *   LANGUAGE= -> ""
1172  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1173  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1174  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1175  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1176  *   LANGUAGE= LANG=C -> ""
1177  */
1178 static const char *get_accept_language(void)
1179 {
1180         if (!cached_accept_language) {
1181                 struct strbuf buf = STRBUF_INIT;
1182                 write_accept_language(&buf);
1183                 if (buf.len > 0)
1184                         cached_accept_language = strbuf_detach(&buf, NULL);
1185         }
1186
1187         return cached_accept_language;
1188 }
1189
1190 /* http_request() targets */
1191 #define HTTP_REQUEST_STRBUF     0
1192 #define HTTP_REQUEST_FILE       1
1193
1194 static int http_request(const char *url,
1195                         void *result, int target,
1196                         const struct http_get_options *options)
1197 {
1198         struct active_request_slot *slot;
1199         struct slot_results results;
1200         struct curl_slist *headers = NULL;
1201         struct strbuf buf = STRBUF_INIT;
1202         const char *accept_language;
1203         int ret;
1204
1205         slot = get_active_slot();
1206         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1207
1208         if (result == NULL) {
1209                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1210         } else {
1211                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1212                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1213
1214                 if (target == HTTP_REQUEST_FILE) {
1215                         long posn = ftell(result);
1216                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1217                                          fwrite);
1218                         if (posn > 0) {
1219                                 strbuf_addf(&buf, "Range: bytes=%ld-", posn);
1220                                 headers = curl_slist_append(headers, buf.buf);
1221                                 strbuf_reset(&buf);
1222                         }
1223                 } else
1224                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1225                                          fwrite_buffer);
1226         }
1227
1228         accept_language = get_accept_language();
1229
1230         if (accept_language)
1231                 headers = curl_slist_append(headers, accept_language);
1232
1233         strbuf_addstr(&buf, "Pragma:");
1234         if (options && options->no_cache)
1235                 strbuf_addstr(&buf, " no-cache");
1236         if (options && options->keep_error)
1237                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1238
1239         headers = curl_slist_append(headers, buf.buf);
1240
1241         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1242         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1243         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1244
1245         ret = run_one_slot(slot, &results);
1246
1247         if (options && options->content_type) {
1248                 struct strbuf raw = STRBUF_INIT;
1249                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1250                 extract_content_type(&raw, options->content_type,
1251                                      options->charset);
1252                 strbuf_release(&raw);
1253         }
1254
1255         if (options && options->effective_url)
1256                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1257                                 options->effective_url);
1258
1259         curl_slist_free_all(headers);
1260         strbuf_release(&buf);
1261
1262         return ret;
1263 }
1264
1265 /*
1266  * Update the "base" url to a more appropriate value, as deduced by
1267  * redirects seen when requesting a URL starting with "url".
1268  *
1269  * The "asked" parameter is a URL that we asked curl to access, and must begin
1270  * with "base".
1271  *
1272  * The "got" parameter is the URL that curl reported to us as where we ended
1273  * up.
1274  *
1275  * Returns 1 if we updated the base url, 0 otherwise.
1276  *
1277  * Our basic strategy is to compare "base" and "asked" to find the bits
1278  * specific to our request. We then strip those bits off of "got" to yield the
1279  * new base. So for example, if our base is "http://example.com/foo.git",
1280  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1281  * with "https://other.example.com/foo.git/info/refs". We would want the
1282  * new URL to become "https://other.example.com/foo.git".
1283  *
1284  * Note that this assumes a sane redirect scheme. It's entirely possible
1285  * in the example above to end up at a URL that does not even end in
1286  * "info/refs".  In such a case we simply punt, as there is not much we can
1287  * do (and such a scheme is unlikely to represent a real git repository,
1288  * which means we are likely about to abort anyway).
1289  */
1290 static int update_url_from_redirect(struct strbuf *base,
1291                                     const char *asked,
1292                                     const struct strbuf *got)
1293 {
1294         const char *tail;
1295         size_t tail_len;
1296
1297         if (!strcmp(asked, got->buf))
1298                 return 0;
1299
1300         if (!skip_prefix(asked, base->buf, &tail))
1301                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1302                     asked, base->buf);
1303
1304         tail_len = strlen(tail);
1305
1306         if (got->len < tail_len ||
1307             strcmp(tail, got->buf + got->len - tail_len))
1308                 return 0; /* insane redirect scheme */
1309
1310         strbuf_reset(base);
1311         strbuf_add(base, got->buf, got->len - tail_len);
1312         return 1;
1313 }
1314
1315 static int http_request_reauth(const char *url,
1316                                void *result, int target,
1317                                struct http_get_options *options)
1318 {
1319         int ret = http_request(url, result, target, options);
1320
1321         if (options && options->effective_url && options->base_url) {
1322                 if (update_url_from_redirect(options->base_url,
1323                                              url, options->effective_url)) {
1324                         credential_from_url(&http_auth, options->base_url->buf);
1325                         url = options->effective_url->buf;
1326                 }
1327         }
1328
1329         if (ret != HTTP_REAUTH)
1330                 return ret;
1331
1332         /*
1333          * If we are using KEEP_ERROR, the previous request may have
1334          * put cruft into our output stream; we should clear it out before
1335          * making our next request. We only know how to do this for
1336          * the strbuf case, but that is enough to satisfy current callers.
1337          */
1338         if (options && options->keep_error) {
1339                 switch (target) {
1340                 case HTTP_REQUEST_STRBUF:
1341                         strbuf_reset(result);
1342                         break;
1343                 default:
1344                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1345                 }
1346         }
1347
1348         credential_fill(&http_auth);
1349
1350         return http_request(url, result, target, options);
1351 }
1352
1353 int http_get_strbuf(const char *url,
1354                     struct strbuf *result,
1355                     struct http_get_options *options)
1356 {
1357         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1358 }
1359
1360 /*
1361  * Downloads a URL and stores the result in the given file.
1362  *
1363  * If a previous interrupted download is detected (i.e. a previous temporary
1364  * file is still around) the download is resumed.
1365  */
1366 static int http_get_file(const char *url, const char *filename,
1367                          struct http_get_options *options)
1368 {
1369         int ret;
1370         struct strbuf tmpfile = STRBUF_INIT;
1371         FILE *result;
1372
1373         strbuf_addf(&tmpfile, "%s.temp", filename);
1374         result = fopen(tmpfile.buf, "a");
1375         if (!result) {
1376                 error("Unable to open local file %s", tmpfile.buf);
1377                 ret = HTTP_ERROR;
1378                 goto cleanup;
1379         }
1380
1381         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1382         fclose(result);
1383
1384         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1385                 ret = HTTP_ERROR;
1386 cleanup:
1387         strbuf_release(&tmpfile);
1388         return ret;
1389 }
1390
1391 int http_fetch_ref(const char *base, struct ref *ref)
1392 {
1393         struct http_get_options options = {0};
1394         char *url;
1395         struct strbuf buffer = STRBUF_INIT;
1396         int ret = -1;
1397
1398         options.no_cache = 1;
1399
1400         url = quote_ref_url(base, ref->name);
1401         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1402                 strbuf_rtrim(&buffer);
1403                 if (buffer.len == 40)
1404                         ret = get_sha1_hex(buffer.buf, ref->old_sha1);
1405                 else if (starts_with(buffer.buf, "ref: ")) {
1406                         ref->symref = xstrdup(buffer.buf + 5);
1407                         ret = 0;
1408                 }
1409         }
1410
1411         strbuf_release(&buffer);
1412         free(url);
1413         return ret;
1414 }
1415
1416 /* Helpers for fetching packs */
1417 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1418 {
1419         char *url, *tmp;
1420         struct strbuf buf = STRBUF_INIT;
1421
1422         if (http_is_verbose)
1423                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1424
1425         end_url_with_slash(&buf, base_url);
1426         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1427         url = strbuf_detach(&buf, NULL);
1428
1429         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1430         tmp = strbuf_detach(&buf, NULL);
1431
1432         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1433                 error("Unable to get pack index %s", url);
1434                 free(tmp);
1435                 tmp = NULL;
1436         }
1437
1438         free(url);
1439         return tmp;
1440 }
1441
1442 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1443         unsigned char *sha1, const char *base_url)
1444 {
1445         struct packed_git *new_pack;
1446         char *tmp_idx = NULL;
1447         int ret;
1448
1449         if (has_pack_index(sha1)) {
1450                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1451                 if (!new_pack)
1452                         return -1; /* parse_pack_index() already issued error message */
1453                 goto add_pack;
1454         }
1455
1456         tmp_idx = fetch_pack_index(sha1, base_url);
1457         if (!tmp_idx)
1458                 return -1;
1459
1460         new_pack = parse_pack_index(sha1, tmp_idx);
1461         if (!new_pack) {
1462                 unlink(tmp_idx);
1463                 free(tmp_idx);
1464
1465                 return -1; /* parse_pack_index() already issued error message */
1466         }
1467
1468         ret = verify_pack_index(new_pack);
1469         if (!ret) {
1470                 close_pack_index(new_pack);
1471                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1472         }
1473         free(tmp_idx);
1474         if (ret)
1475                 return -1;
1476
1477 add_pack:
1478         new_pack->next = *packs_head;
1479         *packs_head = new_pack;
1480         return 0;
1481 }
1482
1483 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1484 {
1485         struct http_get_options options = {0};
1486         int ret = 0, i = 0;
1487         char *url, *data;
1488         struct strbuf buf = STRBUF_INIT;
1489         unsigned char sha1[20];
1490
1491         end_url_with_slash(&buf, base_url);
1492         strbuf_addstr(&buf, "objects/info/packs");
1493         url = strbuf_detach(&buf, NULL);
1494
1495         options.no_cache = 1;
1496         ret = http_get_strbuf(url, &buf, &options);
1497         if (ret != HTTP_OK)
1498                 goto cleanup;
1499
1500         data = buf.buf;
1501         while (i < buf.len) {
1502                 switch (data[i]) {
1503                 case 'P':
1504                         i++;
1505                         if (i + 52 <= buf.len &&
1506                             starts_with(data + i, " pack-") &&
1507                             starts_with(data + i + 46, ".pack\n")) {
1508                                 get_sha1_hex(data + i + 6, sha1);
1509                                 fetch_and_setup_pack_index(packs_head, sha1,
1510                                                       base_url);
1511                                 i += 51;
1512                                 break;
1513                         }
1514                 default:
1515                         while (i < buf.len && data[i] != '\n')
1516                                 i++;
1517                 }
1518                 i++;
1519         }
1520
1521 cleanup:
1522         free(url);
1523         return ret;
1524 }
1525
1526 void release_http_pack_request(struct http_pack_request *preq)
1527 {
1528         if (preq->packfile != NULL) {
1529                 fclose(preq->packfile);
1530                 preq->packfile = NULL;
1531         }
1532         if (preq->range_header != NULL) {
1533                 curl_slist_free_all(preq->range_header);
1534                 preq->range_header = NULL;
1535         }
1536         preq->slot = NULL;
1537         free(preq->url);
1538         free(preq);
1539 }
1540
1541 int finish_http_pack_request(struct http_pack_request *preq)
1542 {
1543         struct packed_git **lst;
1544         struct packed_git *p = preq->target;
1545         char *tmp_idx;
1546         struct child_process ip = CHILD_PROCESS_INIT;
1547         const char *ip_argv[8];
1548
1549         close_pack_index(p);
1550
1551         fclose(preq->packfile);
1552         preq->packfile = NULL;
1553
1554         lst = preq->lst;
1555         while (*lst != p)
1556                 lst = &((*lst)->next);
1557         *lst = (*lst)->next;
1558
1559         tmp_idx = xstrdup(preq->tmpfile);
1560         strcpy(tmp_idx + strlen(tmp_idx) - strlen(".pack.temp"),
1561                ".idx.temp");
1562
1563         ip_argv[0] = "index-pack";
1564         ip_argv[1] = "-o";
1565         ip_argv[2] = tmp_idx;
1566         ip_argv[3] = preq->tmpfile;
1567         ip_argv[4] = NULL;
1568
1569         ip.argv = ip_argv;
1570         ip.git_cmd = 1;
1571         ip.no_stdin = 1;
1572         ip.no_stdout = 1;
1573
1574         if (run_command(&ip)) {
1575                 unlink(preq->tmpfile);
1576                 unlink(tmp_idx);
1577                 free(tmp_idx);
1578                 return -1;
1579         }
1580
1581         unlink(sha1_pack_index_name(p->sha1));
1582
1583         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1584          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1585                 free(tmp_idx);
1586                 return -1;
1587         }
1588
1589         install_packed_git(p);
1590         free(tmp_idx);
1591         return 0;
1592 }
1593
1594 struct http_pack_request *new_http_pack_request(
1595         struct packed_git *target, const char *base_url)
1596 {
1597         long prev_posn = 0;
1598         char range[RANGE_HEADER_SIZE];
1599         struct strbuf buf = STRBUF_INIT;
1600         struct http_pack_request *preq;
1601
1602         preq = xcalloc(1, sizeof(*preq));
1603         preq->target = target;
1604
1605         end_url_with_slash(&buf, base_url);
1606         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1607                 sha1_to_hex(target->sha1));
1608         preq->url = strbuf_detach(&buf, NULL);
1609
1610         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1611                 sha1_pack_name(target->sha1));
1612         preq->packfile = fopen(preq->tmpfile, "a");
1613         if (!preq->packfile) {
1614                 error("Unable to open local file %s for pack",
1615                       preq->tmpfile);
1616                 goto abort;
1617         }
1618
1619         preq->slot = get_active_slot();
1620         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1621         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1622         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1623         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1624                 no_pragma_header);
1625
1626         /*
1627          * If there is data present from a previous transfer attempt,
1628          * resume where it left off
1629          */
1630         prev_posn = ftell(preq->packfile);
1631         if (prev_posn>0) {
1632                 if (http_is_verbose)
1633                         fprintf(stderr,
1634                                 "Resuming fetch of pack %s at byte %ld\n",
1635                                 sha1_to_hex(target->sha1), prev_posn);
1636                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1637                 preq->range_header = curl_slist_append(NULL, range);
1638                 curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1639                         preq->range_header);
1640         }
1641
1642         return preq;
1643
1644 abort:
1645         free(preq->url);
1646         free(preq);
1647         return NULL;
1648 }
1649
1650 /* Helpers for fetching objects (loose) */
1651 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1652                                void *data)
1653 {
1654         unsigned char expn[4096];
1655         size_t size = eltsize * nmemb;
1656         int posn = 0;
1657         struct http_object_request *freq =
1658                 (struct http_object_request *)data;
1659         do {
1660                 ssize_t retval = xwrite(freq->localfile,
1661                                         (char *) ptr + posn, size - posn);
1662                 if (retval < 0)
1663                         return posn;
1664                 posn += retval;
1665         } while (posn < size);
1666
1667         freq->stream.avail_in = size;
1668         freq->stream.next_in = (void *)ptr;
1669         do {
1670                 freq->stream.next_out = expn;
1671                 freq->stream.avail_out = sizeof(expn);
1672                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1673                 git_SHA1_Update(&freq->c, expn,
1674                                 sizeof(expn) - freq->stream.avail_out);
1675         } while (freq->stream.avail_in && freq->zret == Z_OK);
1676         return size;
1677 }
1678
1679 struct http_object_request *new_http_object_request(const char *base_url,
1680         unsigned char *sha1)
1681 {
1682         char *hex = sha1_to_hex(sha1);
1683         const char *filename;
1684         char prevfile[PATH_MAX];
1685         int prevlocal;
1686         char prev_buf[PREV_BUF_SIZE];
1687         ssize_t prev_read = 0;
1688         long prev_posn = 0;
1689         char range[RANGE_HEADER_SIZE];
1690         struct curl_slist *range_header = NULL;
1691         struct http_object_request *freq;
1692
1693         freq = xcalloc(1, sizeof(*freq));
1694         hashcpy(freq->sha1, sha1);
1695         freq->localfile = -1;
1696
1697         filename = sha1_file_name(sha1);
1698         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1699                  "%s.temp", filename);
1700
1701         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1702         unlink_or_warn(prevfile);
1703         rename(freq->tmpfile, prevfile);
1704         unlink_or_warn(freq->tmpfile);
1705
1706         if (freq->localfile != -1)
1707                 error("fd leakage in start: %d", freq->localfile);
1708         freq->localfile = open(freq->tmpfile,
1709                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1710         /*
1711          * This could have failed due to the "lazy directory creation";
1712          * try to mkdir the last path component.
1713          */
1714         if (freq->localfile < 0 && errno == ENOENT) {
1715                 char *dir = strrchr(freq->tmpfile, '/');
1716                 if (dir) {
1717                         *dir = 0;
1718                         mkdir(freq->tmpfile, 0777);
1719                         *dir = '/';
1720                 }
1721                 freq->localfile = open(freq->tmpfile,
1722                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1723         }
1724
1725         if (freq->localfile < 0) {
1726                 error("Couldn't create temporary file %s: %s",
1727                       freq->tmpfile, strerror(errno));
1728                 goto abort;
1729         }
1730
1731         git_inflate_init(&freq->stream);
1732
1733         git_SHA1_Init(&freq->c);
1734
1735         freq->url = get_remote_object_url(base_url, hex, 0);
1736
1737         /*
1738          * If a previous temp file is present, process what was already
1739          * fetched.
1740          */
1741         prevlocal = open(prevfile, O_RDONLY);
1742         if (prevlocal != -1) {
1743                 do {
1744                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1745                         if (prev_read>0) {
1746                                 if (fwrite_sha1_file(prev_buf,
1747                                                      1,
1748                                                      prev_read,
1749                                                      freq) == prev_read) {
1750                                         prev_posn += prev_read;
1751                                 } else {
1752                                         prev_read = -1;
1753                                 }
1754                         }
1755                 } while (prev_read > 0);
1756                 close(prevlocal);
1757         }
1758         unlink_or_warn(prevfile);
1759
1760         /*
1761          * Reset inflate/SHA1 if there was an error reading the previous temp
1762          * file; also rewind to the beginning of the local file.
1763          */
1764         if (prev_read == -1) {
1765                 memset(&freq->stream, 0, sizeof(freq->stream));
1766                 git_inflate_init(&freq->stream);
1767                 git_SHA1_Init(&freq->c);
1768                 if (prev_posn>0) {
1769                         prev_posn = 0;
1770                         lseek(freq->localfile, 0, SEEK_SET);
1771                         if (ftruncate(freq->localfile, 0) < 0) {
1772                                 error("Couldn't truncate temporary file %s: %s",
1773                                           freq->tmpfile, strerror(errno));
1774                                 goto abort;
1775                         }
1776                 }
1777         }
1778
1779         freq->slot = get_active_slot();
1780
1781         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1782         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1783         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1784         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1785         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1786
1787         /*
1788          * If we have successfully processed data from a previous fetch
1789          * attempt, only fetch the data we don't already have.
1790          */
1791         if (prev_posn>0) {
1792                 if (http_is_verbose)
1793                         fprintf(stderr,
1794                                 "Resuming fetch of object %s at byte %ld\n",
1795                                 hex, prev_posn);
1796                 sprintf(range, "Range: bytes=%ld-", prev_posn);
1797                 range_header = curl_slist_append(range_header, range);
1798                 curl_easy_setopt(freq->slot->curl,
1799                                  CURLOPT_HTTPHEADER, range_header);
1800         }
1801
1802         return freq;
1803
1804 abort:
1805         free(freq->url);
1806         free(freq);
1807         return NULL;
1808 }
1809
1810 void process_http_object_request(struct http_object_request *freq)
1811 {
1812         if (freq->slot == NULL)
1813                 return;
1814         freq->curl_result = freq->slot->curl_result;
1815         freq->http_code = freq->slot->http_code;
1816         freq->slot = NULL;
1817 }
1818
1819 int finish_http_object_request(struct http_object_request *freq)
1820 {
1821         struct stat st;
1822
1823         close(freq->localfile);
1824         freq->localfile = -1;
1825
1826         process_http_object_request(freq);
1827
1828         if (freq->http_code == 416) {
1829                 warning("requested range invalid; we may already have all the data.");
1830         } else if (freq->curl_result != CURLE_OK) {
1831                 if (stat(freq->tmpfile, &st) == 0)
1832                         if (st.st_size == 0)
1833                                 unlink_or_warn(freq->tmpfile);
1834                 return -1;
1835         }
1836
1837         git_inflate_end(&freq->stream);
1838         git_SHA1_Final(freq->real_sha1, &freq->c);
1839         if (freq->zret != Z_STREAM_END) {
1840                 unlink_or_warn(freq->tmpfile);
1841                 return -1;
1842         }
1843         if (hashcmp(freq->sha1, freq->real_sha1)) {
1844                 unlink_or_warn(freq->tmpfile);
1845                 return -1;
1846         }
1847         freq->rename =
1848                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
1849
1850         return freq->rename;
1851 }
1852
1853 void abort_http_object_request(struct http_object_request *freq)
1854 {
1855         unlink_or_warn(freq->tmpfile);
1856
1857         release_http_object_request(freq);
1858 }
1859
1860 void release_http_object_request(struct http_object_request *freq)
1861 {
1862         if (freq->localfile != -1) {
1863                 close(freq->localfile);
1864                 freq->localfile = -1;
1865         }
1866         if (freq->url != NULL) {
1867                 free(freq->url);
1868                 freq->url = NULL;
1869         }
1870         if (freq->slot != NULL) {
1871                 freq->slot->callback_func = NULL;
1872                 freq->slot->callback_data = NULL;
1873                 release_active_slot(freq->slot);
1874                 freq->slot = NULL;
1875         }
1876 }