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 *http_proxy_authmethod;
  66 static struct {
  67         const char *name;
  68         long curlauth_param;
  69 } proxy_authmethods[] = {
  70         { "basic", CURLAUTH_BASIC },
  71         { "digest", CURLAUTH_DIGEST },
  72         { "negotiate", CURLAUTH_GSSNEGOTIATE },
  73         { "ntlm", CURLAUTH_NTLM },
  74 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  75         { "anyauth", CURLAUTH_ANY },
  76 #endif
  77         /*
  78          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
  79          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
  80          * here, too
  81          */
  82 };
  83 static const char *curl_cookie_file;
  84 static int curl_save_cookies;
  85 struct credential http_auth = CREDENTIAL_INIT;
  86 static int http_proactive_auth;
  87 static const char *user_agent;
  88
  89 #if LIBCURL_VERSION_NUM >= 0x071700
  90 /* Use CURLOPT_KEYPASSWD as is */
  91 #elif LIBCURL_VERSION_NUM >= 0x070903
  92 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
  93 #else
  94 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
  95 #endif
  96
  97 static struct credential cert_auth = CREDENTIAL_INIT;
  98 static int ssl_cert_password_required;
  99 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 100 static unsigned long http_auth_methods = CURLAUTH_ANY;
 101 #endif
 102
 103 static struct curl_slist *pragma_header;
 104 static struct curl_slist *no_pragma_header;
 105
 106 static struct active_request_slot *active_queue_head;
 107
 108 static char *cached_accept_language;
 109
 110 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 111 {
 112         size_t size = eltsize * nmemb;
 113         struct buffer *buffer = buffer_;
 114
 115         if (size > buffer->buf.len - buffer->posn)
 116                 size = buffer->buf.len - buffer->posn;
 117         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 118         buffer->posn += size;
 119
 120         return size;
 121 }
 122
 123 #ifndef NO_CURL_IOCTL
 124 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 125 {
 126         struct buffer *buffer = clientp;
 127
 128         switch (cmd) {
 129         case CURLIOCMD_NOP:
 130                 return CURLIOE_OK;
 131
 132         case CURLIOCMD_RESTARTREAD:
 133                 buffer->posn = 0;
 134                 return CURLIOE_OK;
 135
 136         default:
 137                 return CURLIOE_UNKNOWNCMD;
 138         }
 139 }
 140 #endif
 141
 142 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 143 {
 144         size_t size = eltsize * nmemb;
 145         struct strbuf *buffer = buffer_;
 146
 147         strbuf_add(buffer, ptr, size);
 148         return size;
 149 }
 150
 151 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 152 {
 153         return eltsize * nmemb;
 154 }
 155
 156 static void closedown_active_slot(struct active_request_slot *slot)
 157 {
 158         active_requests--;
 159         slot->in_use = 0;
 160 }
 161
 162 static void finish_active_slot(struct active_request_slot *slot)
 163 {
 164         closedown_active_slot(slot);
 165         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 166
 167         if (slot->finished != NULL)
 168                 (*slot->finished) = 1;
 169
 170         /* Store slot results so they can be read after the slot is reused */
 171         if (slot->results != NULL) {
 172                 slot->results->curl_result = slot->curl_result;
 173                 slot->results->http_code = slot->http_code;
 174 #if LIBCURL_VERSION_NUM >= 0x070a08
 175                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 176                                   &slot->results->auth_avail);
 177 #else
 178                 slot->results->auth_avail = 0;
 179 #endif
 180         }
 181
 182         /* Run callback if appropriate */
 183         if (slot->callback_func != NULL)
 184                 slot->callback_func(slot->callback_data);
 185 }
 186
 187 #ifdef USE_CURL_MULTI
 188 static void process_curl_messages(void)
 189 {
 190         int num_messages;
 191         struct active_request_slot *slot;
 192         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 193
 194         while (curl_message != NULL) {
 195                 if (curl_message->msg == CURLMSG_DONE) {
 196                         int curl_result = curl_message->data.result;
 197                         slot = active_queue_head;
 198                         while (slot != NULL &&
 199                                slot->curl != curl_message->easy_handle)
 200                                 slot = slot->next;
 201                         if (slot != NULL) {
 202                                 curl_multi_remove_handle(curlm, slot->curl);
 203                                 slot->curl_result = curl_result;
 204                                 finish_active_slot(slot);
 205                         } else {
 206                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 207                         }
 208                 } else {
 209                         fprintf(stderr, "Unknown CURL message received: %d\n",
 210                                 (int)curl_message->msg);
 211                 }
 212                 curl_message = curl_multi_info_read(curlm, &num_messages);
 213         }
 214 }
 215 #endif
 216
 217 static int http_options(const char *var, const char *value, void *cb)
 218 {
 219         if (!strcmp("http.sslverify", var)) {
 220                 curl_ssl_verify = git_config_bool(var, value);
 221                 return 0;
 222         }
 223         if (!strcmp("http.sslcipherlist", var))
 224                 return git_config_string(&ssl_cipherlist, var, value);
 225         if (!strcmp("http.sslversion", var))
 226                 return git_config_string(&ssl_version, var, value);
 227         if (!strcmp("http.sslcert", var))
 228                 return git_config_string(&ssl_cert, var, value);
 229 #if LIBCURL_VERSION_NUM >= 0x070903
 230         if (!strcmp("http.sslkey", var))
 231                 return git_config_string(&ssl_key, var, value);
 232 #endif
 233 #if LIBCURL_VERSION_NUM >= 0x070908
 234         if (!strcmp("http.sslcapath", var))
 235                 return git_config_pathname(&ssl_capath, var, value);
 236 #endif
 237         if (!strcmp("http.sslcainfo", var))
 238                 return git_config_pathname(&ssl_cainfo, var, value);
 239         if (!strcmp("http.sslcertpasswordprotected", var)) {
 240                 ssl_cert_password_required = git_config_bool(var, value);
 241                 return 0;
 242         }
 243         if (!strcmp("http.ssltry", var)) {
 244                 curl_ssl_try = git_config_bool(var, value);
 245                 return 0;
 246         }
 247         if (!strcmp("http.minsessions", var)) {
 248                 min_curl_sessions = git_config_int(var, value);
 249 #ifndef USE_CURL_MULTI
 250                 if (min_curl_sessions > 1)
 251                         min_curl_sessions = 1;
 252 #endif
 253                 return 0;
 254         }
 255 #ifdef USE_CURL_MULTI
 256         if (!strcmp("http.maxrequests", var)) {
 257                 max_requests = git_config_int(var, value);
 258                 return 0;
 259         }
 260 #endif
 261         if (!strcmp("http.lowspeedlimit", var)) {
 262                 curl_low_speed_limit = (long)git_config_int(var, value);
 263                 return 0;
 264         }
 265         if (!strcmp("http.lowspeedtime", var)) {
 266                 curl_low_speed_time = (long)git_config_int(var, value);
 267                 return 0;
 268         }
 269
 270         if (!strcmp("http.noepsv", var)) {
 271                 curl_ftp_no_epsv = git_config_bool(var, value);
 272                 return 0;
 273         }
 274         if (!strcmp("http.proxy", var))
 275                 return git_config_string(&curl_http_proxy, var, value);
 276
 277         if (!strcmp("http.proxyauthmethod", var))
 278                 return git_config_string(&http_proxy_authmethod, var, value);
 279
 280         if (!strcmp("http.cookiefile", var))
 281                 return git_config_string(&curl_cookie_file, var, value);
 282         if (!strcmp("http.savecookies", var)) {
 283                 curl_save_cookies = git_config_bool(var, value);
 284                 return 0;
 285         }
 286
 287         if (!strcmp("http.postbuffer", var)) {
 288                 http_post_buffer = git_config_int(var, value);
 289                 if (http_post_buffer < LARGE_PACKET_MAX)
 290                         http_post_buffer = LARGE_PACKET_MAX;
 291                 return 0;
 292         }
 293
 294         if (!strcmp("http.useragent", var))
 295                 return git_config_string(&user_agent, var, value);
 296
 297         /* Fall back on the default ones */
 298         return git_default_config(var, value, cb);
 299 }
 300
 301 static void init_curl_http_auth(CURL *result)
 302 {
 303         if (!http_auth.username)
 304                 return;
 305
 306         credential_fill(&http_auth);
 307
 308 #if LIBCURL_VERSION_NUM >= 0x071301
 309         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 310         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 311 #else
 312         {
 313                 static struct strbuf up = STRBUF_INIT;
 314                 /*
 315                  * Note that we assume we only ever have a single set of
 316                  * credentials in a given program run, so we do not have
 317                  * to worry about updating this buffer, only setting its
 318                  * initial value.
 319                  */
 320                 if (!up.len)
 321                         strbuf_addf(&up, "%s:%s",
 322                                 http_auth.username, http_auth.password);
 323                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 324         }
 325 #endif
 326 }
 327
 328 /* *var must be free-able */
 329 static void var_override(const char **var, char *value)
 330 {
 331         if (value) {
 332                 free((void *)*var);
 333                 *var = xstrdup(value);
 334         }
 335 }
 336
 337 static void init_curl_proxy_auth(CURL *result)
 338 {
 339         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
 340
 341 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
 342         if (http_proxy_authmethod) {
 343                 int i;
 344                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
 345                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
 346                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
 347                                                 proxy_authmethods[i].curlauth_param);
 348                                 break;
 349                         }
 350                 }
 351                 if (i == ARRAY_SIZE(proxy_authmethods)) {
 352                         warning("unsupported proxy authentication method %s: using anyauth",
 353                                         http_proxy_authmethod);
 354                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 355                 }
 356         }
 357         else
 358                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 359 #endif
 360 }
 361
 362 static int has_cert_password(void)
 363 {
 364         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 365                 return 0;
 366         if (!cert_auth.password) {
 367                 cert_auth.protocol = xstrdup("cert");
 368                 cert_auth.username = xstrdup("");
 369                 cert_auth.path = xstrdup(ssl_cert);
 370                 credential_fill(&cert_auth);
 371         }
 372         return 1;
 373 }
 374
 375 #if LIBCURL_VERSION_NUM >= 0x071900
 376 static void set_curl_keepalive(CURL *c)
 377 {
 378         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 379 }
 380
 381 #elif LIBCURL_VERSION_NUM >= 0x071000
 382 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 383 {
 384         int ka = 1;
 385         int rc;
 386         socklen_t len = (socklen_t)sizeof(ka);
 387
 388         if (type != CURLSOCKTYPE_IPCXN)
 389                 return 0;
 390
 391         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 392         if (rc < 0)
 393                 warning("unable to set SO_KEEPALIVE on socket %s",
 394                         strerror(errno));
 395
 396         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 397 }
 398
 399 static void set_curl_keepalive(CURL *c)
 400 {
 401         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 402 }
 403
 404 #else
 405 static void set_curl_keepalive(CURL *c)
 406 {
 407         /* not supported on older curl versions */
 408 }
 409 #endif
 410
 411 static CURL *get_curl_handle(void)
 412 {
 413         CURL *result = curl_easy_init();
 414         long allowed_protocols = 0;
 415
 416         if (!result)
 417                 die("curl_easy_init failed");
 418
 419         if (!curl_ssl_verify) {
 420                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 421                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 422         } else {
 423                 /* Verify authenticity of the peer's certificate */
 424                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 425                 /* The name in the cert must match whom we tried to connect */
 426                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 427         }
 428
 429 #if LIBCURL_VERSION_NUM >= 0x070907
 430         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 431 #endif
 432 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 433         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 434 #endif
 435
 436         if (http_proactive_auth)
 437                 init_curl_http_auth(result);
 438
 439         if (getenv("GIT_SSL_VERSION"))
 440                 ssl_version = getenv("GIT_SSL_VERSION");
 441         if (ssl_version && *ssl_version) {
 442                 int i;
 443                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 444                         if (!strcmp(ssl_version, sslversions[i].name)) {
 445                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 446                                                  sslversions[i].ssl_version);
 447                                 break;
 448                         }
 449                 }
 450                 if (i == ARRAY_SIZE(sslversions))
 451                         warning("unsupported ssl version %s: using default",
 452                                 ssl_version);
 453         }
 454
 455         if (getenv("GIT_SSL_CIPHER_LIST"))
 456                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 457         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 458                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 459                                 ssl_cipherlist);
 460
 461         if (ssl_cert != NULL)
 462                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 463         if (has_cert_password())
 464                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 465 #if LIBCURL_VERSION_NUM >= 0x070903
 466         if (ssl_key != NULL)
 467                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 468 #endif
 469 #if LIBCURL_VERSION_NUM >= 0x070908
 470         if (ssl_capath != NULL)
 471                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 472 #endif
 473         if (ssl_cainfo != NULL)
 474                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 475
 476         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 477                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 478                                  curl_low_speed_limit);
 479                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 480                                  curl_low_speed_time);
 481         }
 482
 483         curl_easy_setopt(result, CURLOPT_FOLLOWLOCATION, 1);
 484         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 485 #if LIBCURL_VERSION_NUM >= 0x071301
 486         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 487 #elif LIBCURL_VERSION_NUM >= 0x071101
 488         curl_easy_setopt(result, CURLOPT_POST301, 1);
 489 #endif
 490 #if LIBCURL_VERSION_NUM >= 0x071304
 491         if (is_transport_allowed("http"))
 492                 allowed_protocols |= CURLPROTO_HTTP;
 493         if (is_transport_allowed("https"))
 494                 allowed_protocols |= CURLPROTO_HTTPS;
 495         if (is_transport_allowed("ftp"))
 496                 allowed_protocols |= CURLPROTO_FTP;
 497         if (is_transport_allowed("ftps"))
 498                 allowed_protocols |= CURLPROTO_FTPS;
 499         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS, allowed_protocols);
 500 #else
 501         if (transport_restrict_protocols())
 502                 warning("protocol restrictions not applied to curl redirects because\n"
 503                         "your curl version is too old (>= 7.19.4)");
 504 #endif
 505
 506         if (getenv("GIT_CURL_VERBOSE"))
 507                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 508
 509         curl_easy_setopt(result, CURLOPT_USERAGENT,
 510                 user_agent ? user_agent : git_user_agent());
 511
 512         if (curl_ftp_no_epsv)
 513                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 514
 515 #ifdef CURLOPT_USE_SSL
 516         if (curl_ssl_try)
 517                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 518 #endif
 519
 520         if (curl_http_proxy) {
 521                 curl_easy_setopt(result, CURLOPT_PROXY, curl_http_proxy);
 522 #if LIBCURL_VERSION_NUM >= 0x071800
 523                 if (starts_with(curl_http_proxy, "socks5"))
 524                         curl_easy_setopt(result,
 525                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
 526                 else if (starts_with(curl_http_proxy, "socks4a"))
 527                         curl_easy_setopt(result,
 528                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
 529                 else if (starts_with(curl_http_proxy, "socks"))
 530                         curl_easy_setopt(result,
 531                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
 532 #endif
 533         }
 534         init_curl_proxy_auth(result);
 535
 536         set_curl_keepalive(result);
 537
 538         return result;
 539 }
 540
 541 static void set_from_env(const char **var, const char *envname)
 542 {
 543         const char *val = getenv(envname);
 544         if (val)
 545                 *var = val;
 546 }
 547
 548 void http_init(struct remote *remote, const char *url, int proactive_auth)
 549 {
 550         char *low_speed_limit;
 551         char *low_speed_time;
 552         char *normalized_url;
 553         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 554
 555         config.section = "http";
 556         config.key = NULL;
 557         config.collect_fn = http_options;
 558         config.cascade_fn = git_default_config;
 559         config.cb = NULL;
 560
 561         http_is_verbose = 0;
 562         normalized_url = url_normalize(url, &config.url);
 563
 564         git_config(urlmatch_config_entry, &config);
 565         free(normalized_url);
 566
 567         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 568                 die("curl_global_init failed");
 569
 570         http_proactive_auth = proactive_auth;
 571
 572         if (remote && remote->http_proxy)
 573                 curl_http_proxy = xstrdup(remote->http_proxy);
 574
 575         if (remote)
 576                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
 577
 578         pragma_header = curl_slist_append(pragma_header, "Pragma: no-cache");
 579         no_pragma_header = curl_slist_append(no_pragma_header, "Pragma:");
 580
 581 #ifdef USE_CURL_MULTI
 582         {
 583                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
 584                 if (http_max_requests != NULL)
 585                         max_requests = atoi(http_max_requests);
 586         }
 587
 588         curlm = curl_multi_init();
 589         if (!curlm)
 590                 die("curl_multi_init failed");
 591 #endif
 592
 593         if (getenv("GIT_SSL_NO_VERIFY"))
 594                 curl_ssl_verify = 0;
 595
 596         set_from_env(&ssl_cert, "GIT_SSL_CERT");
 597 #if LIBCURL_VERSION_NUM >= 0x070903
 598         set_from_env(&ssl_key, "GIT_SSL_KEY");
 599 #endif
 600 #if LIBCURL_VERSION_NUM >= 0x070908
 601         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
 602 #endif
 603         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
 604
 605         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
 606
 607         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
 608         if (low_speed_limit != NULL)
 609                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
 610         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
 611         if (low_speed_time != NULL)
 612                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
 613
 614         if (curl_ssl_verify == -1)
 615                 curl_ssl_verify = 1;
 616
 617         curl_session_count = 0;
 618 #ifdef USE_CURL_MULTI
 619         if (max_requests < 1)
 620                 max_requests = DEFAULT_MAX_REQUESTS;
 621 #endif
 622
 623         if (getenv("GIT_CURL_FTP_NO_EPSV"))
 624                 curl_ftp_no_epsv = 1;
 625
 626         if (url) {
 627                 credential_from_url(&http_auth, url);
 628                 if (!ssl_cert_password_required &&
 629                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
 630                     starts_with(url, "https://"))
 631                         ssl_cert_password_required = 1;
 632         }
 633
 634 #ifndef NO_CURL_EASY_DUPHANDLE
 635         curl_default = get_curl_handle();
 636 #endif
 637 }
 638
 639 void http_cleanup(void)
 640 {
 641         struct active_request_slot *slot = active_queue_head;
 642
 643         while (slot != NULL) {
 644                 struct active_request_slot *next = slot->next;
 645                 if (slot->curl != NULL) {
 646 #ifdef USE_CURL_MULTI
 647                         curl_multi_remove_handle(curlm, slot->curl);
 648 #endif
 649                         curl_easy_cleanup(slot->curl);
 650                 }
 651                 free(slot);
 652                 slot = next;
 653         }
 654         active_queue_head = NULL;
 655
 656 #ifndef NO_CURL_EASY_DUPHANDLE
 657         curl_easy_cleanup(curl_default);
 658 #endif
 659
 660 #ifdef USE_CURL_MULTI
 661         curl_multi_cleanup(curlm);
 662 #endif
 663         curl_global_cleanup();
 664
 665         curl_slist_free_all(pragma_header);
 666         pragma_header = NULL;
 667
 668         curl_slist_free_all(no_pragma_header);
 669         no_pragma_header = NULL;
 670
 671         if (curl_http_proxy) {
 672                 free((void *)curl_http_proxy);
 673                 curl_http_proxy = NULL;
 674         }
 675
 676         free((void *)http_proxy_authmethod);
 677         http_proxy_authmethod = NULL;
 678
 679         if (cert_auth.password != NULL) {
 680                 memset(cert_auth.password, 0, strlen(cert_auth.password));
 681                 free(cert_auth.password);
 682                 cert_auth.password = NULL;
 683         }
 684         ssl_cert_password_required = 0;
 685
 686         free(cached_accept_language);
 687         cached_accept_language = NULL;
 688 }
 689
 690 struct active_request_slot *get_active_slot(void)
 691 {
 692         struct active_request_slot *slot = active_queue_head;
 693         struct active_request_slot *newslot;
 694
 695 #ifdef USE_CURL_MULTI
 696         int num_transfers;
 697
 698         /* Wait for a slot to open up if the queue is full */
 699         while (active_requests >= max_requests) {
 700                 curl_multi_perform(curlm, &num_transfers);
 701                 if (num_transfers < active_requests)
 702                         process_curl_messages();
 703         }
 704 #endif
 705
 706         while (slot != NULL && slot->in_use)
 707                 slot = slot->next;
 708
 709         if (slot == NULL) {
 710                 newslot = xmalloc(sizeof(*newslot));
 711                 newslot->curl = NULL;
 712                 newslot->in_use = 0;
 713                 newslot->next = NULL;
 714
 715                 slot = active_queue_head;
 716                 if (slot == NULL) {
 717                         active_queue_head = newslot;
 718                 } else {
 719                         while (slot->next != NULL)
 720                                 slot = slot->next;
 721                         slot->next = newslot;
 722                 }
 723                 slot = newslot;
 724         }
 725
 726         if (slot->curl == NULL) {
 727 #ifdef NO_CURL_EASY_DUPHANDLE
 728                 slot->curl = get_curl_handle();
 729 #else
 730                 slot->curl = curl_easy_duphandle(curl_default);
 731 #endif
 732                 curl_session_count++;
 733         }
 734
 735         active_requests++;
 736         slot->in_use = 1;
 737         slot->results = NULL;
 738         slot->finished = NULL;
 739         slot->callback_data = NULL;
 740         slot->callback_func = NULL;
 741         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
 742         if (curl_save_cookies)
 743                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
 744         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
 745         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
 746         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
 747         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
 748         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
 749         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
 750         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
 751         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
 752         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
 753         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
 754 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 755         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
 756 #endif
 757         if (http_auth.password)
 758                 init_curl_http_auth(slot->curl);
 759
 760         return slot;
 761 }
 762
 763 int start_active_slot(struct active_request_slot *slot)
 764 {
 765 #ifdef USE_CURL_MULTI
 766         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
 767         int num_transfers;
 768
 769         if (curlm_result != CURLM_OK &&
 770             curlm_result != CURLM_CALL_MULTI_PERFORM) {
 771                 active_requests--;
 772                 slot->in_use = 0;
 773                 return 0;
 774         }
 775
 776         /*
 777          * We know there must be something to do, since we just added
 778          * something.
 779          */
 780         curl_multi_perform(curlm, &num_transfers);
 781 #endif
 782         return 1;
 783 }
 784
 785 #ifdef USE_CURL_MULTI
 786 struct fill_chain {
 787         void *data;
 788         int (*fill)(void *);
 789         struct fill_chain *next;
 790 };
 791
 792 static struct fill_chain *fill_cfg;
 793
 794 void add_fill_function(void *data, int (*fill)(void *))
 795 {
 796         struct fill_chain *new = xmalloc(sizeof(*new));
 797         struct fill_chain **linkp = &fill_cfg;
 798         new->data = data;
 799         new->fill = fill;
 800         new->next = NULL;
 801         while (*linkp)
 802                 linkp = &(*linkp)->next;
 803         *linkp = new;
 804 }
 805
 806 void fill_active_slots(void)
 807 {
 808         struct active_request_slot *slot = active_queue_head;
 809
 810         while (active_requests < max_requests) {
 811                 struct fill_chain *fill;
 812                 for (fill = fill_cfg; fill; fill = fill->next)
 813                         if (fill->fill(fill->data))
 814                                 break;
 815
 816                 if (!fill)
 817                         break;
 818         }
 819
 820         while (slot != NULL) {
 821                 if (!slot->in_use && slot->curl != NULL
 822                         && curl_session_count > min_curl_sessions) {
 823                         curl_easy_cleanup(slot->curl);
 824                         slot->curl = NULL;
 825                         curl_session_count--;
 826                 }
 827                 slot = slot->next;
 828         }
 829 }
 830
 831 void step_active_slots(void)
 832 {
 833         int num_transfers;
 834         CURLMcode curlm_result;
 835
 836         do {
 837                 curlm_result = curl_multi_perform(curlm, &num_transfers);
 838         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
 839         if (num_transfers < active_requests) {
 840                 process_curl_messages();
 841                 fill_active_slots();
 842         }
 843 }
 844 #endif
 845
 846 void run_active_slot(struct active_request_slot *slot)
 847 {
 848 #ifdef USE_CURL_MULTI
 849         fd_set readfds;
 850         fd_set writefds;
 851         fd_set excfds;
 852         int max_fd;
 853         struct timeval select_timeout;
 854         int finished = 0;
 855
 856         slot->finished = &finished;
 857         while (!finished) {
 858                 step_active_slots();
 859
 860                 if (slot->in_use) {
 861 #if LIBCURL_VERSION_NUM >= 0x070f04
 862                         long curl_timeout;
 863                         curl_multi_timeout(curlm, &curl_timeout);
 864                         if (curl_timeout == 0) {
 865                                 continue;
 866                         } else if (curl_timeout == -1) {
 867                                 select_timeout.tv_sec  = 0;
 868                                 select_timeout.tv_usec = 50000;
 869                         } else {
 870                                 select_timeout.tv_sec  =  curl_timeout / 1000;
 871                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
 872                         }
 873 #else
 874                         select_timeout.tv_sec  = 0;
 875                         select_timeout.tv_usec = 50000;
 876 #endif
 877
 878                         max_fd = -1;
 879                         FD_ZERO(&readfds);
 880                         FD_ZERO(&writefds);
 881                         FD_ZERO(&excfds);
 882                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
 883
 884                         /*
 885                          * It can happen that curl_multi_timeout returns a pathologically
 886                          * long timeout when curl_multi_fdset returns no file descriptors
 887                          * to read.  See commit message for more details.
 888                          */
 889                         if (max_fd < 0 &&
 890                             (select_timeout.tv_sec > 0 ||
 891                              select_timeout.tv_usec > 50000)) {
 892                                 select_timeout.tv_sec  = 0;
 893                                 select_timeout.tv_usec = 50000;
 894                         }
 895
 896                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
 897                 }
 898         }
 899 #else
 900         while (slot->in_use) {
 901                 slot->curl_result = curl_easy_perform(slot->curl);
 902                 finish_active_slot(slot);
 903         }
 904 #endif
 905 }
 906
 907 static void release_active_slot(struct active_request_slot *slot)
 908 {
 909         closedown_active_slot(slot);
 910         if (slot->curl && curl_session_count > min_curl_sessions) {
 911 #ifdef USE_CURL_MULTI
 912                 curl_multi_remove_handle(curlm, slot->curl);
 913 #endif
 914                 curl_easy_cleanup(slot->curl);
 915                 slot->curl = NULL;
 916                 curl_session_count--;
 917         }
 918 #ifdef USE_CURL_MULTI
 919         fill_active_slots();
 920 #endif
 921 }
 922
 923 void finish_all_active_slots(void)
 924 {
 925         struct active_request_slot *slot = active_queue_head;
 926
 927         while (slot != NULL)
 928                 if (slot->in_use) {
 929                         run_active_slot(slot);
 930                         slot = active_queue_head;
 931                 } else {
 932                         slot = slot->next;
 933                 }
 934 }
 935
 936 /* Helpers for modifying and creating URLs */
 937 static inline int needs_quote(int ch)
 938 {
 939         if (((ch >= 'A') && (ch <= 'Z'))
 940                         || ((ch >= 'a') && (ch <= 'z'))
 941                         || ((ch >= '0') && (ch <= '9'))
 942                         || (ch == '/')
 943                         || (ch == '-')
 944                         || (ch == '.'))
 945                 return 0;
 946         return 1;
 947 }
 948
 949 static char *quote_ref_url(const char *base, const char *ref)
 950 {
 951         struct strbuf buf = STRBUF_INIT;
 952         const char *cp;
 953         int ch;
 954
 955         end_url_with_slash(&buf, base);
 956
 957         for (cp = ref; (ch = *cp) != 0; cp++)
 958                 if (needs_quote(ch))
 959                         strbuf_addf(&buf, "%%%02x", ch);
 960                 else
 961                         strbuf_addch(&buf, *cp);
 962
 963         return strbuf_detach(&buf, NULL);
 964 }
 965
 966 void append_remote_object_url(struct strbuf *buf, const char *url,
 967                               const char *hex,
 968                               int only_two_digit_prefix)
 969 {
 970         end_url_with_slash(buf, url);
 971
 972         strbuf_addf(buf, "objects/%.*s/", 2, hex);
 973         if (!only_two_digit_prefix)
 974                 strbuf_addf(buf, "%s", hex+2);
 975 }
 976
 977 char *get_remote_object_url(const char *url, const char *hex,
 978                             int only_two_digit_prefix)
 979 {
 980         struct strbuf buf = STRBUF_INIT;
 981         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
 982         return strbuf_detach(&buf, NULL);
 983 }
 984
 985 static int handle_curl_result(struct slot_results *results)
 986 {
 987         /*
 988          * If we see a failing http code with CURLE_OK, we have turned off
 989          * FAILONERROR (to keep the server's custom error response), and should
 990          * translate the code into failure here.
 991          */
 992         if (results->curl_result == CURLE_OK &&
 993             results->http_code >= 400) {
 994                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
 995                 /*
 996                  * Normally curl will already have put the "reason phrase"
 997                  * from the server into curl_errorstr; unfortunately without
 998                  * FAILONERROR it is lost, so we can give only the numeric
 999                  * status code.
1000                  */
1001                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1002                          "The requested URL returned error: %ld",
1003                          results->http_code);
1004         }
1005
1006         if (results->curl_result == CURLE_OK) {
1007                 credential_approve(&http_auth);
1008                 return HTTP_OK;
1009         } else if (missing_target(results))
1010                 return HTTP_MISSING_TARGET;
1011         else if (results->http_code == 401) {
1012                 if (http_auth.username && http_auth.password) {
1013                         credential_reject(&http_auth);
1014                         return HTTP_NOAUTH;
1015                 } else {
1016 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1017                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1018 #endif
1019                         return HTTP_REAUTH;
1020                 }
1021         } else {
1022 #if LIBCURL_VERSION_NUM >= 0x070c00
1023                 if (!curl_errorstr[0])
1024                         strlcpy(curl_errorstr,
1025                                 curl_easy_strerror(results->curl_result),
1026                                 sizeof(curl_errorstr));
1027 #endif
1028                 return HTTP_ERROR;
1029         }
1030 }
1031
1032 int run_one_slot(struct active_request_slot *slot,
1033                  struct slot_results *results)
1034 {
1035         slot->results = results;
1036         if (!start_active_slot(slot)) {
1037                 snprintf(curl_errorstr, sizeof(curl_errorstr),
1038                          "failed to start HTTP request");
1039                 return HTTP_START_FAILED;
1040         }
1041
1042         run_active_slot(slot);
1043         return handle_curl_result(results);
1044 }
1045
1046 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1047 {
1048         char *ptr;
1049         CURLcode ret;
1050
1051         strbuf_reset(buf);
1052         ret = curl_easy_getinfo(curl, info, &ptr);
1053         if (!ret && ptr)
1054                 strbuf_addstr(buf, ptr);
1055         return ret;
1056 }
1057
1058 /*
1059  * Check for and extract a content-type parameter. "raw"
1060  * should be positioned at the start of the potential
1061  * parameter, with any whitespace already removed.
1062  *
1063  * "name" is the name of the parameter. The value is appended
1064  * to "out".
1065  */
1066 static int extract_param(const char *raw, const char *name,
1067                          struct strbuf *out)
1068 {
1069         size_t len = strlen(name);
1070
1071         if (strncasecmp(raw, name, len))
1072                 return -1;
1073         raw += len;
1074
1075         if (*raw != '=')
1076                 return -1;
1077         raw++;
1078
1079         while (*raw && !isspace(*raw) && *raw != ';')
1080                 strbuf_addch(out, *raw++);
1081         return 0;
1082 }
1083
1084 /*
1085  * Extract a normalized version of the content type, with any
1086  * spaces suppressed, all letters lowercased, and no trailing ";"
1087  * or parameters.
1088  *
1089  * Note that we will silently remove even invalid whitespace. For
1090  * example, "text / plain" is specifically forbidden by RFC 2616,
1091  * but "text/plain" is the only reasonable output, and this keeps
1092  * our code simple.
1093  *
1094  * If the "charset" argument is not NULL, store the value of any
1095  * charset parameter there.
1096  *
1097  * Example:
1098  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1099  *   "text / plain" -> "text/plain"
1100  */
1101 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1102                                  struct strbuf *charset)
1103 {
1104         const char *p;
1105
1106         strbuf_reset(type);
1107         strbuf_grow(type, raw->len);
1108         for (p = raw->buf; *p; p++) {
1109                 if (isspace(*p))
1110                         continue;
1111                 if (*p == ';') {
1112                         p++;
1113                         break;
1114                 }
1115                 strbuf_addch(type, tolower(*p));
1116         }
1117
1118         if (!charset)
1119                 return;
1120
1121         strbuf_reset(charset);
1122         while (*p) {
1123                 while (isspace(*p) || *p == ';')
1124                         p++;
1125                 if (!extract_param(p, "charset", charset))
1126                         return;
1127                 while (*p && !isspace(*p))
1128                         p++;
1129         }
1130
1131         if (!charset->len && starts_with(type->buf, "text/"))
1132                 strbuf_addstr(charset, "ISO-8859-1");
1133 }
1134
1135 static void write_accept_language(struct strbuf *buf)
1136 {
1137         /*
1138          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1139          * that, q-value will be smaller than 0.001, the minimum q-value the
1140          * HTTP specification allows. See
1141          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1142          */
1143         const int MAX_DECIMAL_PLACES = 3;
1144         const int MAX_LANGUAGE_TAGS = 1000;
1145         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1146         char **language_tags = NULL;
1147         int num_langs = 0;
1148         const char *s = get_preferred_languages();
1149         int i;
1150         struct strbuf tag = STRBUF_INIT;
1151
1152         /* Don't add Accept-Language header if no language is preferred. */
1153         if (!s)
1154                 return;
1155
1156         /*
1157          * Split the colon-separated string of preferred languages into
1158          * language_tags array.
1159          */
1160         do {
1161                 /* collect language tag */
1162                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1163                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1164
1165                 /* skip .codeset, @modifier and any other unnecessary parts */
1166                 while (*s && *s != ':')
1167                         s++;
1168
1169                 if (tag.len) {
1170                         num_langs++;
1171                         REALLOC_ARRAY(language_tags, num_langs);
1172                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1173                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1174                                 break;
1175                 }
1176         } while (*s++);
1177
1178         /* write Accept-Language header into buf */
1179         if (num_langs) {
1180                 int last_buf_len = 0;
1181                 int max_q;
1182                 int decimal_places;
1183                 char q_format[32];
1184
1185                 /* add '*' */
1186                 REALLOC_ARRAY(language_tags, num_langs + 1);
1187                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1188
1189                 /* compute decimal_places */
1190                 for (max_q = 1, decimal_places = 0;
1191                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1192                      decimal_places++, max_q *= 10)
1193                         ;
1194
1195                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1196
1197                 strbuf_addstr(buf, "Accept-Language: ");
1198
1199                 for (i = 0; i < num_langs; i++) {
1200                         if (i > 0)
1201                                 strbuf_addstr(buf, ", ");
1202
1203                         strbuf_addstr(buf, language_tags[i]);
1204
1205                         if (i > 0)
1206                                 strbuf_addf(buf, q_format, max_q - i);
1207
1208                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1209                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1210                                 break;
1211                         }
1212
1213                         last_buf_len = buf->len;
1214                 }
1215         }
1216
1217         /* free language tags -- last one is a static '*' */
1218         for (i = 0; i < num_langs - 1; i++)
1219                 free(language_tags[i]);
1220         free(language_tags);
1221 }
1222
1223 /*
1224  * Get an Accept-Language header which indicates user's preferred languages.
1225  *
1226  * Examples:
1227  *   LANGUAGE= -> ""
1228  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1229  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1230  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1231  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1232  *   LANGUAGE= LANG=C -> ""
1233  */
1234 static const char *get_accept_language(void)
1235 {
1236         if (!cached_accept_language) {
1237                 struct strbuf buf = STRBUF_INIT;
1238                 write_accept_language(&buf);
1239                 if (buf.len > 0)
1240                         cached_accept_language = strbuf_detach(&buf, NULL);
1241         }
1242
1243         return cached_accept_language;
1244 }
1245
1246 static void http_opt_request_remainder(CURL *curl, off_t pos)
1247 {
1248         char buf[128];
1249         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1250         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1251 }
1252
1253 /* http_request() targets */
1254 #define HTTP_REQUEST_STRBUF     0
1255 #define HTTP_REQUEST_FILE       1
1256
1257 static int http_request(const char *url,
1258                         void *result, int target,
1259                         const struct http_get_options *options)
1260 {
1261         struct active_request_slot *slot;
1262         struct slot_results results;
1263         struct curl_slist *headers = NULL;
1264         struct strbuf buf = STRBUF_INIT;
1265         const char *accept_language;
1266         int ret;
1267
1268         slot = get_active_slot();
1269         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1270
1271         if (result == NULL) {
1272                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1273         } else {
1274                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1275                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1276
1277                 if (target == HTTP_REQUEST_FILE) {
1278                         off_t posn = ftello(result);
1279                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1280                                          fwrite);
1281                         if (posn > 0)
1282                                 http_opt_request_remainder(slot->curl, posn);
1283                 } else
1284                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1285                                          fwrite_buffer);
1286         }
1287
1288         accept_language = get_accept_language();
1289
1290         if (accept_language)
1291                 headers = curl_slist_append(headers, accept_language);
1292
1293         strbuf_addstr(&buf, "Pragma:");
1294         if (options && options->no_cache)
1295                 strbuf_addstr(&buf, " no-cache");
1296         if (options && options->keep_error)
1297                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1298
1299         headers = curl_slist_append(headers, buf.buf);
1300
1301         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1302         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1303         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "gzip");
1304
1305         ret = run_one_slot(slot, &results);
1306
1307         if (options && options->content_type) {
1308                 struct strbuf raw = STRBUF_INIT;
1309                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1310                 extract_content_type(&raw, options->content_type,
1311                                      options->charset);
1312                 strbuf_release(&raw);
1313         }
1314
1315         if (options && options->effective_url)
1316                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1317                                 options->effective_url);
1318
1319         curl_slist_free_all(headers);
1320         strbuf_release(&buf);
1321
1322         return ret;
1323 }
1324
1325 /*
1326  * Update the "base" url to a more appropriate value, as deduced by
1327  * redirects seen when requesting a URL starting with "url".
1328  *
1329  * The "asked" parameter is a URL that we asked curl to access, and must begin
1330  * with "base".
1331  *
1332  * The "got" parameter is the URL that curl reported to us as where we ended
1333  * up.
1334  *
1335  * Returns 1 if we updated the base url, 0 otherwise.
1336  *
1337  * Our basic strategy is to compare "base" and "asked" to find the bits
1338  * specific to our request. We then strip those bits off of "got" to yield the
1339  * new base. So for example, if our base is "http://example.com/foo.git",
1340  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1341  * with "https://other.example.com/foo.git/info/refs". We would want the
1342  * new URL to become "https://other.example.com/foo.git".
1343  *
1344  * Note that this assumes a sane redirect scheme. It's entirely possible
1345  * in the example above to end up at a URL that does not even end in
1346  * "info/refs".  In such a case we simply punt, as there is not much we can
1347  * do (and such a scheme is unlikely to represent a real git repository,
1348  * which means we are likely about to abort anyway).
1349  */
1350 static int update_url_from_redirect(struct strbuf *base,
1351                                     const char *asked,
1352                                     const struct strbuf *got)
1353 {
1354         const char *tail;
1355         size_t tail_len;
1356
1357         if (!strcmp(asked, got->buf))
1358                 return 0;
1359
1360         if (!skip_prefix(asked, base->buf, &tail))
1361                 die("BUG: update_url_from_redirect: %s is not a superset of %s",
1362                     asked, base->buf);
1363
1364         tail_len = strlen(tail);
1365
1366         if (got->len < tail_len ||
1367             strcmp(tail, got->buf + got->len - tail_len))
1368                 return 0; /* insane redirect scheme */
1369
1370         strbuf_reset(base);
1371         strbuf_add(base, got->buf, got->len - tail_len);
1372         return 1;
1373 }
1374
1375 static int http_request_reauth(const char *url,
1376                                void *result, int target,
1377                                struct http_get_options *options)
1378 {
1379         int ret = http_request(url, result, target, options);
1380
1381         if (options && options->effective_url && options->base_url) {
1382                 if (update_url_from_redirect(options->base_url,
1383                                              url, options->effective_url)) {
1384                         credential_from_url(&http_auth, options->base_url->buf);
1385                         url = options->effective_url->buf;
1386                 }
1387         }
1388
1389         if (ret != HTTP_REAUTH)
1390                 return ret;
1391
1392         /*
1393          * If we are using KEEP_ERROR, the previous request may have
1394          * put cruft into our output stream; we should clear it out before
1395          * making our next request. We only know how to do this for
1396          * the strbuf case, but that is enough to satisfy current callers.
1397          */
1398         if (options && options->keep_error) {
1399                 switch (target) {
1400                 case HTTP_REQUEST_STRBUF:
1401                         strbuf_reset(result);
1402                         break;
1403                 default:
1404                         die("BUG: HTTP_KEEP_ERROR is only supported with strbufs");
1405                 }
1406         }
1407
1408         credential_fill(&http_auth);
1409
1410         return http_request(url, result, target, options);
1411 }
1412
1413 int http_get_strbuf(const char *url,
1414                     struct strbuf *result,
1415                     struct http_get_options *options)
1416 {
1417         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1418 }
1419
1420 /*
1421  * Downloads a URL and stores the result in the given file.
1422  *
1423  * If a previous interrupted download is detected (i.e. a previous temporary
1424  * file is still around) the download is resumed.
1425  */
1426 static int http_get_file(const char *url, const char *filename,
1427                          struct http_get_options *options)
1428 {
1429         int ret;
1430         struct strbuf tmpfile = STRBUF_INIT;
1431         FILE *result;
1432
1433         strbuf_addf(&tmpfile, "%s.temp", filename);
1434         result = fopen(tmpfile.buf, "a");
1435         if (!result) {
1436                 error("Unable to open local file %s", tmpfile.buf);
1437                 ret = HTTP_ERROR;
1438                 goto cleanup;
1439         }
1440
1441         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1442         fclose(result);
1443
1444         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1445                 ret = HTTP_ERROR;
1446 cleanup:
1447         strbuf_release(&tmpfile);
1448         return ret;
1449 }
1450
1451 int http_fetch_ref(const char *base, struct ref *ref)
1452 {
1453         struct http_get_options options = {0};
1454         char *url;
1455         struct strbuf buffer = STRBUF_INIT;
1456         int ret = -1;
1457
1458         options.no_cache = 1;
1459
1460         url = quote_ref_url(base, ref->name);
1461         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1462                 strbuf_rtrim(&buffer);
1463                 if (buffer.len == 40)
1464                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
1465                 else if (starts_with(buffer.buf, "ref: ")) {
1466                         ref->symref = xstrdup(buffer.buf + 5);
1467                         ret = 0;
1468                 }
1469         }
1470
1471         strbuf_release(&buffer);
1472         free(url);
1473         return ret;
1474 }
1475
1476 /* Helpers for fetching packs */
1477 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1478 {
1479         char *url, *tmp;
1480         struct strbuf buf = STRBUF_INIT;
1481
1482         if (http_is_verbose)
1483                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1484
1485         end_url_with_slash(&buf, base_url);
1486         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1487         url = strbuf_detach(&buf, NULL);
1488
1489         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1490         tmp = strbuf_detach(&buf, NULL);
1491
1492         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1493                 error("Unable to get pack index %s", url);
1494                 free(tmp);
1495                 tmp = NULL;
1496         }
1497
1498         free(url);
1499         return tmp;
1500 }
1501
1502 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1503         unsigned char *sha1, const char *base_url)
1504 {
1505         struct packed_git *new_pack;
1506         char *tmp_idx = NULL;
1507         int ret;
1508
1509         if (has_pack_index(sha1)) {
1510                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
1511                 if (!new_pack)
1512                         return -1; /* parse_pack_index() already issued error message */
1513                 goto add_pack;
1514         }
1515
1516         tmp_idx = fetch_pack_index(sha1, base_url);
1517         if (!tmp_idx)
1518                 return -1;
1519
1520         new_pack = parse_pack_index(sha1, tmp_idx);
1521         if (!new_pack) {
1522                 unlink(tmp_idx);
1523                 free(tmp_idx);
1524
1525                 return -1; /* parse_pack_index() already issued error message */
1526         }
1527
1528         ret = verify_pack_index(new_pack);
1529         if (!ret) {
1530                 close_pack_index(new_pack);
1531                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
1532         }
1533         free(tmp_idx);
1534         if (ret)
1535                 return -1;
1536
1537 add_pack:
1538         new_pack->next = *packs_head;
1539         *packs_head = new_pack;
1540         return 0;
1541 }
1542
1543 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
1544 {
1545         struct http_get_options options = {0};
1546         int ret = 0, i = 0;
1547         char *url, *data;
1548         struct strbuf buf = STRBUF_INIT;
1549         unsigned char sha1[20];
1550
1551         end_url_with_slash(&buf, base_url);
1552         strbuf_addstr(&buf, "objects/info/packs");
1553         url = strbuf_detach(&buf, NULL);
1554
1555         options.no_cache = 1;
1556         ret = http_get_strbuf(url, &buf, &options);
1557         if (ret != HTTP_OK)
1558                 goto cleanup;
1559
1560         data = buf.buf;
1561         while (i < buf.len) {
1562                 switch (data[i]) {
1563                 case 'P':
1564                         i++;
1565                         if (i + 52 <= buf.len &&
1566                             starts_with(data + i, " pack-") &&
1567                             starts_with(data + i + 46, ".pack\n")) {
1568                                 get_sha1_hex(data + i + 6, sha1);
1569                                 fetch_and_setup_pack_index(packs_head, sha1,
1570                                                       base_url);
1571                                 i += 51;
1572                                 break;
1573                         }
1574                 default:
1575                         while (i < buf.len && data[i] != '\n')
1576                                 i++;
1577                 }
1578                 i++;
1579         }
1580
1581 cleanup:
1582         free(url);
1583         return ret;
1584 }
1585
1586 void release_http_pack_request(struct http_pack_request *preq)
1587 {
1588         if (preq->packfile != NULL) {
1589                 fclose(preq->packfile);
1590                 preq->packfile = NULL;
1591         }
1592         preq->slot = NULL;
1593         free(preq->url);
1594         free(preq);
1595 }
1596
1597 int finish_http_pack_request(struct http_pack_request *preq)
1598 {
1599         struct packed_git **lst;
1600         struct packed_git *p = preq->target;
1601         char *tmp_idx;
1602         size_t len;
1603         struct child_process ip = CHILD_PROCESS_INIT;
1604         const char *ip_argv[8];
1605
1606         close_pack_index(p);
1607
1608         fclose(preq->packfile);
1609         preq->packfile = NULL;
1610
1611         lst = preq->lst;
1612         while (*lst != p)
1613                 lst = &((*lst)->next);
1614         *lst = (*lst)->next;
1615
1616         if (!strip_suffix(preq->tmpfile, ".pack.temp", &len))
1617                 die("BUG: pack tmpfile does not end in .pack.temp?");
1618         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile);
1619
1620         ip_argv[0] = "index-pack";
1621         ip_argv[1] = "-o";
1622         ip_argv[2] = tmp_idx;
1623         ip_argv[3] = preq->tmpfile;
1624         ip_argv[4] = NULL;
1625
1626         ip.argv = ip_argv;
1627         ip.git_cmd = 1;
1628         ip.no_stdin = 1;
1629         ip.no_stdout = 1;
1630
1631         if (run_command(&ip)) {
1632                 unlink(preq->tmpfile);
1633                 unlink(tmp_idx);
1634                 free(tmp_idx);
1635                 return -1;
1636         }
1637
1638         unlink(sha1_pack_index_name(p->sha1));
1639
1640         if (finalize_object_file(preq->tmpfile, sha1_pack_name(p->sha1))
1641          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
1642                 free(tmp_idx);
1643                 return -1;
1644         }
1645
1646         install_packed_git(p);
1647         free(tmp_idx);
1648         return 0;
1649 }
1650
1651 struct http_pack_request *new_http_pack_request(
1652         struct packed_git *target, const char *base_url)
1653 {
1654         off_t prev_posn = 0;
1655         struct strbuf buf = STRBUF_INIT;
1656         struct http_pack_request *preq;
1657
1658         preq = xcalloc(1, sizeof(*preq));
1659         preq->target = target;
1660
1661         end_url_with_slash(&buf, base_url);
1662         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
1663                 sha1_to_hex(target->sha1));
1664         preq->url = strbuf_detach(&buf, NULL);
1665
1666         snprintf(preq->tmpfile, sizeof(preq->tmpfile), "%s.temp",
1667                 sha1_pack_name(target->sha1));
1668         preq->packfile = fopen(preq->tmpfile, "a");
1669         if (!preq->packfile) {
1670                 error("Unable to open local file %s for pack",
1671                       preq->tmpfile);
1672                 goto abort;
1673         }
1674
1675         preq->slot = get_active_slot();
1676         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
1677         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
1678         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
1679         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
1680                 no_pragma_header);
1681
1682         /*
1683          * If there is data present from a previous transfer attempt,
1684          * resume where it left off
1685          */
1686         prev_posn = ftello(preq->packfile);
1687         if (prev_posn>0) {
1688                 if (http_is_verbose)
1689                         fprintf(stderr,
1690                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
1691                                 sha1_to_hex(target->sha1), (uintmax_t)prev_posn);
1692                 http_opt_request_remainder(preq->slot->curl, prev_posn);
1693         }
1694
1695         return preq;
1696
1697 abort:
1698         free(preq->url);
1699         free(preq);
1700         return NULL;
1701 }
1702
1703 /* Helpers for fetching objects (loose) */
1704 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
1705                                void *data)
1706 {
1707         unsigned char expn[4096];
1708         size_t size = eltsize * nmemb;
1709         int posn = 0;
1710         struct http_object_request *freq =
1711                 (struct http_object_request *)data;
1712         do {
1713                 ssize_t retval = xwrite(freq->localfile,
1714                                         (char *) ptr + posn, size - posn);
1715                 if (retval < 0)
1716                         return posn;
1717                 posn += retval;
1718         } while (posn < size);
1719
1720         freq->stream.avail_in = size;
1721         freq->stream.next_in = (void *)ptr;
1722         do {
1723                 freq->stream.next_out = expn;
1724                 freq->stream.avail_out = sizeof(expn);
1725                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
1726                 git_SHA1_Update(&freq->c, expn,
1727                                 sizeof(expn) - freq->stream.avail_out);
1728         } while (freq->stream.avail_in && freq->zret == Z_OK);
1729         return size;
1730 }
1731
1732 struct http_object_request *new_http_object_request(const char *base_url,
1733         unsigned char *sha1)
1734 {
1735         char *hex = sha1_to_hex(sha1);
1736         const char *filename;
1737         char prevfile[PATH_MAX];
1738         int prevlocal;
1739         char prev_buf[PREV_BUF_SIZE];
1740         ssize_t prev_read = 0;
1741         off_t prev_posn = 0;
1742         struct http_object_request *freq;
1743
1744         freq = xcalloc(1, sizeof(*freq));
1745         hashcpy(freq->sha1, sha1);
1746         freq->localfile = -1;
1747
1748         filename = sha1_file_name(sha1);
1749         snprintf(freq->tmpfile, sizeof(freq->tmpfile),
1750                  "%s.temp", filename);
1751
1752         snprintf(prevfile, sizeof(prevfile), "%s.prev", filename);
1753         unlink_or_warn(prevfile);
1754         rename(freq->tmpfile, prevfile);
1755         unlink_or_warn(freq->tmpfile);
1756
1757         if (freq->localfile != -1)
1758                 error("fd leakage in start: %d", freq->localfile);
1759         freq->localfile = open(freq->tmpfile,
1760                                O_WRONLY | O_CREAT | O_EXCL, 0666);
1761         /*
1762          * This could have failed due to the "lazy directory creation";
1763          * try to mkdir the last path component.
1764          */
1765         if (freq->localfile < 0 && errno == ENOENT) {
1766                 char *dir = strrchr(freq->tmpfile, '/');
1767                 if (dir) {
1768                         *dir = 0;
1769                         mkdir(freq->tmpfile, 0777);
1770                         *dir = '/';
1771                 }
1772                 freq->localfile = open(freq->tmpfile,
1773                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
1774         }
1775
1776         if (freq->localfile < 0) {
1777                 error("Couldn't create temporary file %s: %s",
1778                       freq->tmpfile, strerror(errno));
1779                 goto abort;
1780         }
1781
1782         git_inflate_init(&freq->stream);
1783
1784         git_SHA1_Init(&freq->c);
1785
1786         freq->url = get_remote_object_url(base_url, hex, 0);
1787
1788         /*
1789          * If a previous temp file is present, process what was already
1790          * fetched.
1791          */
1792         prevlocal = open(prevfile, O_RDONLY);
1793         if (prevlocal != -1) {
1794                 do {
1795                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
1796                         if (prev_read>0) {
1797                                 if (fwrite_sha1_file(prev_buf,
1798                                                      1,
1799                                                      prev_read,
1800                                                      freq) == prev_read) {
1801                                         prev_posn += prev_read;
1802                                 } else {
1803                                         prev_read = -1;
1804                                 }
1805                         }
1806                 } while (prev_read > 0);
1807                 close(prevlocal);
1808         }
1809         unlink_or_warn(prevfile);
1810
1811         /*
1812          * Reset inflate/SHA1 if there was an error reading the previous temp
1813          * file; also rewind to the beginning of the local file.
1814          */
1815         if (prev_read == -1) {
1816                 memset(&freq->stream, 0, sizeof(freq->stream));
1817                 git_inflate_init(&freq->stream);
1818                 git_SHA1_Init(&freq->c);
1819                 if (prev_posn>0) {
1820                         prev_posn = 0;
1821                         lseek(freq->localfile, 0, SEEK_SET);
1822                         if (ftruncate(freq->localfile, 0) < 0) {
1823                                 error("Couldn't truncate temporary file %s: %s",
1824                                           freq->tmpfile, strerror(errno));
1825                                 goto abort;
1826                         }
1827                 }
1828         }
1829
1830         freq->slot = get_active_slot();
1831
1832         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
1833         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
1834         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
1835         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
1836         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
1837
1838         /*
1839          * If we have successfully processed data from a previous fetch
1840          * attempt, only fetch the data we don't already have.
1841          */
1842         if (prev_posn>0) {
1843                 if (http_is_verbose)
1844                         fprintf(stderr,
1845                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
1846                                 hex, (uintmax_t)prev_posn);
1847                 http_opt_request_remainder(freq->slot->curl, prev_posn);
1848         }
1849
1850         return freq;
1851
1852 abort:
1853         free(freq->url);
1854         free(freq);
1855         return NULL;
1856 }
1857
1858 void process_http_object_request(struct http_object_request *freq)
1859 {
1860         if (freq->slot == NULL)
1861                 return;
1862         freq->curl_result = freq->slot->curl_result;
1863         freq->http_code = freq->slot->http_code;
1864         freq->slot = NULL;
1865 }
1866
1867 int finish_http_object_request(struct http_object_request *freq)
1868 {
1869         struct stat st;
1870
1871         close(freq->localfile);
1872         freq->localfile = -1;
1873
1874         process_http_object_request(freq);
1875
1876         if (freq->http_code == 416) {
1877                 warning("requested range invalid; we may already have all the data.");
1878         } else if (freq->curl_result != CURLE_OK) {
1879                 if (stat(freq->tmpfile, &st) == 0)
1880                         if (st.st_size == 0)
1881                                 unlink_or_warn(freq->tmpfile);
1882                 return -1;
1883         }
1884
1885         git_inflate_end(&freq->stream);
1886         git_SHA1_Final(freq->real_sha1, &freq->c);
1887         if (freq->zret != Z_STREAM_END) {
1888                 unlink_or_warn(freq->tmpfile);
1889                 return -1;
1890         }
1891         if (hashcmp(freq->sha1, freq->real_sha1)) {
1892                 unlink_or_warn(freq->tmpfile);
1893                 return -1;
1894         }
1895         freq->rename =
1896                 finalize_object_file(freq->tmpfile, sha1_file_name(freq->sha1));
1897
1898         return freq->rename;
1899 }
1900
1901 void abort_http_object_request(struct http_object_request *freq)
1902 {
1903         unlink_or_warn(freq->tmpfile);
1904
1905         release_http_object_request(freq);
1906 }
1907
1908 void release_http_object_request(struct http_object_request *freq)
1909 {
1910         if (freq->localfile != -1) {
1911                 close(freq->localfile);
1912                 freq->localfile = -1;
1913         }
1914         if (freq->url != NULL) {
1915                 free(freq->url);
1916                 freq->url = NULL;
1917         }
1918         if (freq->slot != NULL) {
1919                 freq->slot->callback_func = NULL;
1920                 freq->slot->callback_data = NULL;
1921                 release_active_slot(freq->slot);
1922                 freq->slot = NULL;
1923         }
1924 }