http.c

   1 #include "git-compat-util.h"
   2 #include "http.h"
   3 #include "config.h"
   4 #include "pack.h"
   5 #include "sideband.h"
   6 #include "run-command.h"
   7 #include "url.h"
   8 #include "urlmatch.h"
   9 #include "credential.h"
  10 #include "version.h"
  11 #include "pkt-line.h"
  12 #include "gettext.h"
  13 #include "transport.h"
  14 #include "packfile.h"
  15 #include "protocol.h"
  16 #include "string-list.h"
  17 #include "object-store.h"
  18
  19 static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
  20 static int trace_curl_data = 1;
  21 static struct string_list cookies_to_redact = STRING_LIST_INIT_DUP;
  22 #if LIBCURL_VERSION_NUM >= 0x070a08
  23 long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
  24 #else
  25 long int git_curl_ipresolve;
  26 #endif
  27 int active_requests;
  28 int http_is_verbose;
  29 ssize_t http_post_buffer = 16 * LARGE_PACKET_MAX;
  30
  31 #if LIBCURL_VERSION_NUM >= 0x070a06
  32 #define LIBCURL_CAN_HANDLE_AUTH_ANY
  33 #endif
  34
  35 static int min_curl_sessions = 1;
  36 static int curl_session_count;
  37 #ifdef USE_CURL_MULTI
  38 static int max_requests = -1;
  39 static CURLM *curlm;
  40 #endif
  41 #ifndef NO_CURL_EASY_DUPHANDLE
  42 static CURL *curl_default;
  43 #endif
  44
  45 #define PREV_BUF_SIZE 4096
  46
  47 char curl_errorstr[CURL_ERROR_SIZE];
  48
  49 static int curl_ssl_verify = -1;
  50 static int curl_ssl_try;
  51 static const char *ssl_cert;
  52 static const char *ssl_cipherlist;
  53 static const char *ssl_version;
  54 static struct {
  55         const char *name;
  56         long ssl_version;
  57 } sslversions[] = {
  58         { "sslv2", CURL_SSLVERSION_SSLv2 },
  59         { "sslv3", CURL_SSLVERSION_SSLv3 },
  60         { "tlsv1", CURL_SSLVERSION_TLSv1 },
  61 #if LIBCURL_VERSION_NUM >= 0x072200
  62         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
  63         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  64         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  65 #endif
  66 #if LIBCURL_VERSION_NUM >= 0x073400
  67         { "tlsv1.3", CURL_SSLVERSION_TLSv1_3 },
  68 #endif
  69 };
  70 #if LIBCURL_VERSION_NUM >= 0x070903
  71 static const char *ssl_key;
  72 #endif
  73 #if LIBCURL_VERSION_NUM >= 0x070908
  74 static const char *ssl_capath;
  75 #endif
  76 #if LIBCURL_VERSION_NUM >= 0x071304
  77 static const char *curl_no_proxy;
  78 #endif
  79 #if LIBCURL_VERSION_NUM >= 0x072c00
  80 static const char *ssl_pinnedkey;
  81 #endif
  82 static const char *ssl_cainfo;
  83 static long curl_low_speed_limit = -1;
  84 static long curl_low_speed_time = -1;
  85 static int curl_ftp_no_epsv;
  86 static const char *curl_http_proxy;
  87 static const char *http_proxy_authmethod;
  88 static struct {
  89         const char *name;
  90         long curlauth_param;
  91 } proxy_authmethods[] = {
  92         { "basic", CURLAUTH_BASIC },
  93         { "digest", CURLAUTH_DIGEST },
  94         { "negotiate", CURLAUTH_GSSNEGOTIATE },
  95         { "ntlm", CURLAUTH_NTLM },
  96 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  97         { "anyauth", CURLAUTH_ANY },
  98 #endif
  99         /*
 100          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
 101          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
 102          * here, too
 103          */
 104 };
 105 #ifdef CURLGSSAPI_DELEGATION_FLAG
 106 static const char *curl_deleg;
 107 static struct {
 108         const char *name;
 109         long curl_deleg_param;
 110 } curl_deleg_levels[] = {
 111         { "none", CURLGSSAPI_DELEGATION_NONE },
 112         { "policy", CURLGSSAPI_DELEGATION_POLICY_FLAG },
 113         { "always", CURLGSSAPI_DELEGATION_FLAG },
 114 };
 115 #endif
 116
 117 static struct credential proxy_auth = CREDENTIAL_INIT;
 118 static const char *curl_proxyuserpwd;
 119 static const char *curl_cookie_file;
 120 static int curl_save_cookies;
 121 struct credential http_auth = CREDENTIAL_INIT;
 122 static int http_proactive_auth;
 123 static const char *user_agent;
 124 static int curl_empty_auth = -1;
 125
 126 enum http_follow_config http_follow_config = HTTP_FOLLOW_INITIAL;
 127
 128 #if LIBCURL_VERSION_NUM >= 0x071700
 129 /* Use CURLOPT_KEYPASSWD as is */
 130 #elif LIBCURL_VERSION_NUM >= 0x070903
 131 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
 132 #else
 133 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
 134 #endif
 135
 136 static struct credential cert_auth = CREDENTIAL_INIT;
 137 static int ssl_cert_password_required;
 138 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 139 static unsigned long http_auth_methods = CURLAUTH_ANY;
 140 static int http_auth_methods_restricted;
 141 /* Modes for which empty_auth cannot actually help us. */
 142 static unsigned long empty_auth_useless =
 143         CURLAUTH_BASIC
 144 #ifdef CURLAUTH_DIGEST_IE
 145         | CURLAUTH_DIGEST_IE
 146 #endif
 147         | CURLAUTH_DIGEST;
 148 #endif
 149
 150 static struct curl_slist *pragma_header;
 151 static struct curl_slist *no_pragma_header;
 152 static struct curl_slist *extra_http_headers;
 153
 154 static struct active_request_slot *active_queue_head;
 155
 156 static char *cached_accept_language;
 157
 158 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 159 {
 160         size_t size = eltsize * nmemb;
 161         struct buffer *buffer = buffer_;
 162
 163         if (size > buffer->buf.len - buffer->posn)
 164                 size = buffer->buf.len - buffer->posn;
 165         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 166         buffer->posn += size;
 167
 168         return size;
 169 }
 170
 171 #ifndef NO_CURL_IOCTL
 172 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 173 {
 174         struct buffer *buffer = clientp;
 175
 176         switch (cmd) {
 177         case CURLIOCMD_NOP:
 178                 return CURLIOE_OK;
 179
 180         case CURLIOCMD_RESTARTREAD:
 181                 buffer->posn = 0;
 182                 return CURLIOE_OK;
 183
 184         default:
 185                 return CURLIOE_UNKNOWNCMD;
 186         }
 187 }
 188 #endif
 189
 190 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 191 {
 192         size_t size = eltsize * nmemb;
 193         struct strbuf *buffer = buffer_;
 194
 195         strbuf_add(buffer, ptr, size);
 196         return size;
 197 }
 198
 199 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 200 {
 201         return eltsize * nmemb;
 202 }
 203
 204 static void closedown_active_slot(struct active_request_slot *slot)
 205 {
 206         active_requests--;
 207         slot->in_use = 0;
 208 }
 209
 210 static void finish_active_slot(struct active_request_slot *slot)
 211 {
 212         closedown_active_slot(slot);
 213         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 214
 215         if (slot->finished != NULL)
 216                 (*slot->finished) = 1;
 217
 218         /* Store slot results so they can be read after the slot is reused */
 219         if (slot->results != NULL) {
 220                 slot->results->curl_result = slot->curl_result;
 221                 slot->results->http_code = slot->http_code;
 222 #if LIBCURL_VERSION_NUM >= 0x070a08
 223                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 224                                   &slot->results->auth_avail);
 225 #else
 226                 slot->results->auth_avail = 0;
 227 #endif
 228
 229                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
 230                         &slot->results->http_connectcode);
 231         }
 232
 233         /* Run callback if appropriate */
 234         if (slot->callback_func != NULL)
 235                 slot->callback_func(slot->callback_data);
 236 }
 237
 238 static void xmulti_remove_handle(struct active_request_slot *slot)
 239 {
 240 #ifdef USE_CURL_MULTI
 241         curl_multi_remove_handle(curlm, slot->curl);
 242 #endif
 243 }
 244
 245 #ifdef USE_CURL_MULTI
 246 static void process_curl_messages(void)
 247 {
 248         int num_messages;
 249         struct active_request_slot *slot;
 250         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 251
 252         while (curl_message != NULL) {
 253                 if (curl_message->msg == CURLMSG_DONE) {
 254                         int curl_result = curl_message->data.result;
 255                         slot = active_queue_head;
 256                         while (slot != NULL &&
 257                                slot->curl != curl_message->easy_handle)
 258                                 slot = slot->next;
 259                         if (slot != NULL) {
 260                                 xmulti_remove_handle(slot);
 261                                 slot->curl_result = curl_result;
 262                                 finish_active_slot(slot);
 263                         } else {
 264                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 265                         }
 266                 } else {
 267                         fprintf(stderr, "Unknown CURL message received: %d\n",
 268                                 (int)curl_message->msg);
 269                 }
 270                 curl_message = curl_multi_info_read(curlm, &num_messages);
 271         }
 272 }
 273 #endif
 274
 275 static int http_options(const char *var, const char *value, void *cb)
 276 {
 277         if (!strcmp("http.sslverify", var)) {
 278                 curl_ssl_verify = git_config_bool(var, value);
 279                 return 0;
 280         }
 281         if (!strcmp("http.sslcipherlist", var))
 282                 return git_config_string(&ssl_cipherlist, var, value);
 283         if (!strcmp("http.sslversion", var))
 284                 return git_config_string(&ssl_version, var, value);
 285         if (!strcmp("http.sslcert", var))
 286                 return git_config_pathname(&ssl_cert, var, value);
 287 #if LIBCURL_VERSION_NUM >= 0x070903
 288         if (!strcmp("http.sslkey", var))
 289                 return git_config_pathname(&ssl_key, var, value);
 290 #endif
 291 #if LIBCURL_VERSION_NUM >= 0x070908
 292         if (!strcmp("http.sslcapath", var))
 293                 return git_config_pathname(&ssl_capath, var, value);
 294 #endif
 295         if (!strcmp("http.sslcainfo", var))
 296                 return git_config_pathname(&ssl_cainfo, var, value);
 297         if (!strcmp("http.sslcertpasswordprotected", var)) {
 298                 ssl_cert_password_required = git_config_bool(var, value);
 299                 return 0;
 300         }
 301         if (!strcmp("http.ssltry", var)) {
 302                 curl_ssl_try = git_config_bool(var, value);
 303                 return 0;
 304         }
 305         if (!strcmp("http.minsessions", var)) {
 306                 min_curl_sessions = git_config_int(var, value);
 307 #ifndef USE_CURL_MULTI
 308                 if (min_curl_sessions > 1)
 309                         min_curl_sessions = 1;
 310 #endif
 311                 return 0;
 312         }
 313 #ifdef USE_CURL_MULTI
 314         if (!strcmp("http.maxrequests", var)) {
 315                 max_requests = git_config_int(var, value);
 316                 return 0;
 317         }
 318 #endif
 319         if (!strcmp("http.lowspeedlimit", var)) {
 320                 curl_low_speed_limit = (long)git_config_int(var, value);
 321                 return 0;
 322         }
 323         if (!strcmp("http.lowspeedtime", var)) {
 324                 curl_low_speed_time = (long)git_config_int(var, value);
 325                 return 0;
 326         }
 327
 328         if (!strcmp("http.noepsv", var)) {
 329                 curl_ftp_no_epsv = git_config_bool(var, value);
 330                 return 0;
 331         }
 332         if (!strcmp("http.proxy", var))
 333                 return git_config_string(&curl_http_proxy, var, value);
 334
 335         if (!strcmp("http.proxyauthmethod", var))
 336                 return git_config_string(&http_proxy_authmethod, var, value);
 337
 338         if (!strcmp("http.cookiefile", var))
 339                 return git_config_pathname(&curl_cookie_file, var, value);
 340         if (!strcmp("http.savecookies", var)) {
 341                 curl_save_cookies = git_config_bool(var, value);
 342                 return 0;
 343         }
 344
 345         if (!strcmp("http.postbuffer", var)) {
 346                 http_post_buffer = git_config_ssize_t(var, value);
 347                 if (http_post_buffer < 0)
 348                         warning(_("negative value for http.postbuffer; defaulting to %d"), LARGE_PACKET_MAX);
 349                 if (http_post_buffer < LARGE_PACKET_MAX)
 350                         http_post_buffer = LARGE_PACKET_MAX;
 351                 return 0;
 352         }
 353
 354         if (!strcmp("http.useragent", var))
 355                 return git_config_string(&user_agent, var, value);
 356
 357         if (!strcmp("http.emptyauth", var)) {
 358                 if (value && !strcmp("auto", value))
 359                         curl_empty_auth = -1;
 360                 else
 361                         curl_empty_auth = git_config_bool(var, value);
 362                 return 0;
 363         }
 364
 365         if (!strcmp("http.delegation", var)) {
 366 #ifdef CURLGSSAPI_DELEGATION_FLAG
 367                 return git_config_string(&curl_deleg, var, value);
 368 #else
 369                 warning(_("Delegation control is not supported with cURL < 7.22.0"));
 370                 return 0;
 371 #endif
 372         }
 373
 374         if (!strcmp("http.pinnedpubkey", var)) {
 375 #if LIBCURL_VERSION_NUM >= 0x072c00
 376                 return git_config_pathname(&ssl_pinnedkey, var, value);
 377 #else
 378                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
 379                 return 0;
 380 #endif
 381         }
 382
 383         if (!strcmp("http.extraheader", var)) {
 384                 if (!value) {
 385                         return config_error_nonbool(var);
 386                 } else if (!*value) {
 387                         curl_slist_free_all(extra_http_headers);
 388                         extra_http_headers = NULL;
 389                 } else {
 390                         extra_http_headers =
 391                                 curl_slist_append(extra_http_headers, value);
 392                 }
 393                 return 0;
 394         }
 395
 396         if (!strcmp("http.followredirects", var)) {
 397                 if (value && !strcmp(value, "initial"))
 398                         http_follow_config = HTTP_FOLLOW_INITIAL;
 399                 else if (git_config_bool(var, value))
 400                         http_follow_config = HTTP_FOLLOW_ALWAYS;
 401                 else
 402                         http_follow_config = HTTP_FOLLOW_NONE;
 403                 return 0;
 404         }
 405
 406         /* Fall back on the default ones */
 407         return git_default_config(var, value, cb);
 408 }
 409
 410 static int curl_empty_auth_enabled(void)
 411 {
 412         if (curl_empty_auth >= 0)
 413                 return curl_empty_auth;
 414
 415 #ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
 416         /*
 417          * Our libcurl is too old to do AUTH_ANY in the first place;
 418          * just default to turning the feature off.
 419          */
 420 #else
 421         /*
 422          * In the automatic case, kick in the empty-auth
 423          * hack as long as we would potentially try some
 424          * method more exotic than "Basic" or "Digest".
 425          *
 426          * But only do this when this is our second or
 427          * subsequent request, as by then we know what
 428          * methods are available.
 429          */
 430         if (http_auth_methods_restricted &&
 431             (http_auth_methods & ~empty_auth_useless))
 432                 return 1;
 433 #endif
 434         return 0;
 435 }
 436
 437 static void init_curl_http_auth(CURL *result)
 438 {
 439         if (!http_auth.username || !*http_auth.username) {
 440                 if (curl_empty_auth_enabled())
 441                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
 442                 return;
 443         }
 444
 445         credential_fill(&http_auth);
 446
 447 #if LIBCURL_VERSION_NUM >= 0x071301
 448         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 449         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 450 #else
 451         {
 452                 static struct strbuf up = STRBUF_INIT;
 453                 /*
 454                  * Note that we assume we only ever have a single set of
 455                  * credentials in a given program run, so we do not have
 456                  * to worry about updating this buffer, only setting its
 457                  * initial value.
 458                  */
 459                 if (!up.len)
 460                         strbuf_addf(&up, "%s:%s",
 461                                 http_auth.username, http_auth.password);
 462                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 463         }
 464 #endif
 465 }
 466
 467 /* *var must be free-able */
 468 static void var_override(const char **var, char *value)
 469 {
 470         if (value) {
 471                 free((void *)*var);
 472                 *var = xstrdup(value);
 473         }
 474 }
 475
 476 static void set_proxyauth_name_password(CURL *result)
 477 {
 478 #if LIBCURL_VERSION_NUM >= 0x071301
 479                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
 480                         proxy_auth.username);
 481                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
 482                         proxy_auth.password);
 483 #else
 484                 struct strbuf s = STRBUF_INIT;
 485
 486                 strbuf_addstr_urlencode(&s, proxy_auth.username, 1);
 487                 strbuf_addch(&s, ':');
 488                 strbuf_addstr_urlencode(&s, proxy_auth.password, 1);
 489                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
 490                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
 491 #endif
 492 }
 493
 494 static void init_curl_proxy_auth(CURL *result)
 495 {
 496         if (proxy_auth.username) {
 497                 if (!proxy_auth.password)
 498                         credential_fill(&proxy_auth);
 499                 set_proxyauth_name_password(result);
 500         }
 501
 502         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
 503
 504 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
 505         if (http_proxy_authmethod) {
 506                 int i;
 507                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
 508                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
 509                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
 510                                                 proxy_authmethods[i].curlauth_param);
 511                                 break;
 512                         }
 513                 }
 514                 if (i == ARRAY_SIZE(proxy_authmethods)) {
 515                         warning("unsupported proxy authentication method %s: using anyauth",
 516                                         http_proxy_authmethod);
 517                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 518                 }
 519         }
 520         else
 521                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 522 #endif
 523 }
 524
 525 static int has_cert_password(void)
 526 {
 527         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 528                 return 0;
 529         if (!cert_auth.password) {
 530                 cert_auth.protocol = xstrdup("cert");
 531                 cert_auth.username = xstrdup("");
 532                 cert_auth.path = xstrdup(ssl_cert);
 533                 credential_fill(&cert_auth);
 534         }
 535         return 1;
 536 }
 537
 538 #if LIBCURL_VERSION_NUM >= 0x071900
 539 static void set_curl_keepalive(CURL *c)
 540 {
 541         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 542 }
 543
 544 #elif LIBCURL_VERSION_NUM >= 0x071000
 545 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 546 {
 547         int ka = 1;
 548         int rc;
 549         socklen_t len = (socklen_t)sizeof(ka);
 550
 551         if (type != CURLSOCKTYPE_IPCXN)
 552                 return 0;
 553
 554         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 555         if (rc < 0)
 556                 warning_errno("unable to set SO_KEEPALIVE on socket");
 557
 558         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 559 }
 560
 561 static void set_curl_keepalive(CURL *c)
 562 {
 563         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 564 }
 565
 566 #else
 567 static void set_curl_keepalive(CURL *c)
 568 {
 569         /* not supported on older curl versions */
 570 }
 571 #endif
 572
 573 static void redact_sensitive_header(struct strbuf *header)
 574 {
 575         const char *sensitive_header;
 576
 577         if (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
 578             skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header)) {
 579                 /* The first token is the type, which is OK to log */
 580                 while (isspace(*sensitive_header))
 581                         sensitive_header++;
 582                 while (*sensitive_header && !isspace(*sensitive_header))
 583                         sensitive_header++;
 584                 /* Everything else is opaque and possibly sensitive */
 585                 strbuf_setlen(header,  sensitive_header - header->buf);
 586                 strbuf_addstr(header, " <redacted>");
 587         } else if (cookies_to_redact.nr &&
 588                    skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
 589                 struct strbuf redacted_header = STRBUF_INIT;
 590                 char *cookie;
 591
 592                 while (isspace(*sensitive_header))
 593                         sensitive_header++;
 594
 595                 /*
 596                  * The contents of header starting from sensitive_header will
 597                  * subsequently be overridden, so it is fine to mutate this
 598                  * string (hence the assignment to "char *").
 599                  */
 600                 cookie = (char *) sensitive_header;
 601
 602                 while (cookie) {
 603                         char *equals;
 604                         char *semicolon = strstr(cookie, "; ");
 605                         if (semicolon)
 606                                 *semicolon = 0;
 607                         equals = strchrnul(cookie, '=');
 608                         if (!equals) {
 609                                 /* invalid cookie, just append and continue */
 610                                 strbuf_addstr(&redacted_header, cookie);
 611                                 continue;
 612                         }
 613                         *equals = 0; /* temporarily set to NUL for lookup */
 614                         if (string_list_lookup(&cookies_to_redact, cookie)) {
 615                                 strbuf_addstr(&redacted_header, cookie);
 616                                 strbuf_addstr(&redacted_header, "=<redacted>");
 617                         } else {
 618                                 *equals = '=';
 619                                 strbuf_addstr(&redacted_header, cookie);
 620                         }
 621                         if (semicolon) {
 622                                 /*
 623                                  * There are more cookies. (Or, for some
 624                                  * reason, the input string ends in "; ".)
 625                                  */
 626                                 strbuf_addstr(&redacted_header, "; ");
 627                                 cookie = semicolon + strlen("; ");
 628                         } else {
 629                                 cookie = NULL;
 630                         }
 631                 }
 632
 633                 strbuf_setlen(header, sensitive_header - header->buf);
 634                 strbuf_addbuf(header, &redacted_header);
 635         }
 636 }
 637
 638 static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
 639 {
 640         struct strbuf out = STRBUF_INIT;
 641         struct strbuf **headers, **header;
 642
 643         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 644                 text, (long)size, (long)size);
 645         trace_strbuf(&trace_curl, &out);
 646         strbuf_reset(&out);
 647         strbuf_add(&out, ptr, size);
 648         headers = strbuf_split_max(&out, '\n', 0);
 649
 650         for (header = headers; *header; header++) {
 651                 if (hide_sensitive_header)
 652                         redact_sensitive_header(*header);
 653                 strbuf_insert((*header), 0, text, strlen(text));
 654                 strbuf_insert((*header), strlen(text), ": ", 2);
 655                 strbuf_rtrim((*header));
 656                 strbuf_addch((*header), '\n');
 657                 trace_strbuf(&trace_curl, (*header));
 658         }
 659         strbuf_list_free(headers);
 660         strbuf_release(&out);
 661 }
 662
 663 static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
 664 {
 665         size_t i;
 666         struct strbuf out = STRBUF_INIT;
 667         unsigned int width = 60;
 668
 669         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 670                 text, (long)size, (long)size);
 671         trace_strbuf(&trace_curl, &out);
 672
 673         for (i = 0; i < size; i += width) {
 674                 size_t w;
 675
 676                 strbuf_reset(&out);
 677                 strbuf_addf(&out, "%s: ", text);
 678                 for (w = 0; (w < width) && (i + w < size); w++) {
 679                         unsigned char ch = ptr[i + w];
 680
 681                         strbuf_addch(&out,
 682                                        (ch >= 0x20) && (ch < 0x80)
 683                                        ? ch : '.');
 684                 }
 685                 strbuf_addch(&out, '\n');
 686                 trace_strbuf(&trace_curl, &out);
 687         }
 688         strbuf_release(&out);
 689 }
 690
 691 static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
 692 {
 693         const char *text;
 694         enum { NO_FILTER = 0, DO_FILTER = 1 };
 695
 696         switch (type) {
 697         case CURLINFO_TEXT:
 698                 trace_printf_key(&trace_curl, "== Info: %s", data);
 699                 break;
 700         case CURLINFO_HEADER_OUT:
 701                 text = "=> Send header";
 702                 curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
 703                 break;
 704         case CURLINFO_DATA_OUT:
 705                 if (trace_curl_data) {
 706                         text = "=> Send data";
 707                         curl_dump_data(text, (unsigned char *)data, size);
 708                 }
 709                 break;
 710         case CURLINFO_SSL_DATA_OUT:
 711                 if (trace_curl_data) {
 712                         text = "=> Send SSL data";
 713                         curl_dump_data(text, (unsigned char *)data, size);
 714                 }
 715                 break;
 716         case CURLINFO_HEADER_IN:
 717                 text = "<= Recv header";
 718                 curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
 719                 break;
 720         case CURLINFO_DATA_IN:
 721                 if (trace_curl_data) {
 722                         text = "<= Recv data";
 723                         curl_dump_data(text, (unsigned char *)data, size);
 724                 }
 725                 break;
 726         case CURLINFO_SSL_DATA_IN:
 727                 if (trace_curl_data) {
 728                         text = "<= Recv SSL data";
 729                         curl_dump_data(text, (unsigned char *)data, size);
 730                 }
 731                 break;
 732
 733         default:                /* we ignore unknown types by default */
 734                 return 0;
 735         }
 736         return 0;
 737 }
 738
 739 void setup_curl_trace(CURL *handle)
 740 {
 741         if (!trace_want(&trace_curl))
 742                 return;
 743         curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
 744         curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
 745         curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
 746 }
 747
 748 #ifdef CURLPROTO_HTTP
 749 static long get_curl_allowed_protocols(int from_user)
 750 {
 751         long allowed_protocols = 0;
 752
 753         if (is_transport_allowed("http", from_user))
 754                 allowed_protocols |= CURLPROTO_HTTP;
 755         if (is_transport_allowed("https", from_user))
 756                 allowed_protocols |= CURLPROTO_HTTPS;
 757         if (is_transport_allowed("ftp", from_user))
 758                 allowed_protocols |= CURLPROTO_FTP;
 759         if (is_transport_allowed("ftps", from_user))
 760                 allowed_protocols |= CURLPROTO_FTPS;
 761
 762         return allowed_protocols;
 763 }
 764 #endif
 765
 766 static CURL *get_curl_handle(void)
 767 {
 768         CURL *result = curl_easy_init();
 769
 770         if (!result)
 771                 die("curl_easy_init failed");
 772
 773         if (!curl_ssl_verify) {
 774                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 775                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 776         } else {
 777                 /* Verify authenticity of the peer's certificate */
 778                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 779                 /* The name in the cert must match whom we tried to connect */
 780                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 781         }
 782
 783 #if LIBCURL_VERSION_NUM >= 0x070907
 784         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 785 #endif
 786 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 787         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 788 #endif
 789
 790 #ifdef CURLGSSAPI_DELEGATION_FLAG
 791         if (curl_deleg) {
 792                 int i;
 793                 for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
 794                         if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
 795                                 curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
 796                                                 curl_deleg_levels[i].curl_deleg_param);
 797                                 break;
 798                         }
 799                 }
 800                 if (i == ARRAY_SIZE(curl_deleg_levels))
 801                         warning("Unknown delegation method '%s': using default",
 802                                 curl_deleg);
 803         }
 804 #endif
 805
 806         if (http_proactive_auth)
 807                 init_curl_http_auth(result);
 808
 809         if (getenv("GIT_SSL_VERSION"))
 810                 ssl_version = getenv("GIT_SSL_VERSION");
 811         if (ssl_version && *ssl_version) {
 812                 int i;
 813                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 814                         if (!strcmp(ssl_version, sslversions[i].name)) {
 815                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 816                                                  sslversions[i].ssl_version);
 817                                 break;
 818                         }
 819                 }
 820                 if (i == ARRAY_SIZE(sslversions))
 821                         warning("unsupported ssl version %s: using default",
 822                                 ssl_version);
 823         }
 824
 825         if (getenv("GIT_SSL_CIPHER_LIST"))
 826                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 827         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 828                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 829                                 ssl_cipherlist);
 830
 831         if (ssl_cert != NULL)
 832                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 833         if (has_cert_password())
 834                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 835 #if LIBCURL_VERSION_NUM >= 0x070903
 836         if (ssl_key != NULL)
 837                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 838 #endif
 839 #if LIBCURL_VERSION_NUM >= 0x070908
 840         if (ssl_capath != NULL)
 841                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 842 #endif
 843 #if LIBCURL_VERSION_NUM >= 0x072c00
 844         if (ssl_pinnedkey != NULL)
 845                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 846 #endif
 847         if (ssl_cainfo != NULL)
 848                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 849
 850         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 851                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 852                                  curl_low_speed_limit);
 853                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 854                                  curl_low_speed_time);
 855         }
 856
 857         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 858 #if LIBCURL_VERSION_NUM >= 0x071301
 859         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 860 #elif LIBCURL_VERSION_NUM >= 0x071101
 861         curl_easy_setopt(result, CURLOPT_POST301, 1);
 862 #endif
 863 #ifdef CURLPROTO_HTTP
 864         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
 865                          get_curl_allowed_protocols(0));
 866         curl_easy_setopt(result, CURLOPT_PROTOCOLS,
 867                          get_curl_allowed_protocols(-1));
 868 #else
 869         warning("protocol restrictions not applied to curl redirects because\n"
 870                 "your curl version is too old (>= 7.19.4)");
 871 #endif
 872         if (getenv("GIT_CURL_VERBOSE"))
 873                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1L);
 874         setup_curl_trace(result);
 875         if (getenv("GIT_TRACE_CURL_NO_DATA"))
 876                 trace_curl_data = 0;
 877         if (getenv("GIT_REDACT_COOKIES")) {
 878                 string_list_split(&cookies_to_redact,
 879                                   getenv("GIT_REDACT_COOKIES"), ',', -1);
 880                 string_list_sort(&cookies_to_redact);
 881         }
 882
 883         curl_easy_setopt(result, CURLOPT_USERAGENT,
 884                 user_agent ? user_agent : git_user_agent());
 885
 886         if (curl_ftp_no_epsv)
 887                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 888
 889 #ifdef CURLOPT_USE_SSL
 890         if (curl_ssl_try)
 891                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 892 #endif
 893
 894         /*
 895          * CURL also examines these variables as a fallback; but we need to query
 896          * them here in order to decide whether to prompt for missing password (cf.
 897          * init_curl_proxy_auth()).
 898          *
 899          * Unlike many other common environment variables, these are historically
 900          * lowercase only. It appears that CURL did not know this and implemented
 901          * only uppercase variants, which was later corrected to take both - with
 902          * the exception of http_proxy, which is lowercase only also in CURL. As
 903          * the lowercase versions are the historical quasi-standard, they take
 904          * precedence here, as in CURL.
 905          */
 906         if (!curl_http_proxy) {
 907                 if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
 908                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
 909                         var_override(&curl_http_proxy, getenv("https_proxy"));
 910                 } else {
 911                         var_override(&curl_http_proxy, getenv("http_proxy"));
 912                 }
 913                 if (!curl_http_proxy) {
 914                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
 915                         var_override(&curl_http_proxy, getenv("all_proxy"));
 916                 }
 917         }
 918
 919         if (curl_http_proxy && curl_http_proxy[0] == '\0') {
 920                 /*
 921                  * Handle case with the empty http.proxy value here to keep
 922                  * common code clean.
 923                  * NB: empty option disables proxying at all.
 924                  */
 925                 curl_easy_setopt(result, CURLOPT_PROXY, "");
 926         } else if (curl_http_proxy) {
 927 #if LIBCURL_VERSION_NUM >= 0x071800
 928                 if (starts_with(curl_http_proxy, "socks5h"))
 929                         curl_easy_setopt(result,
 930                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
 931                 else if (starts_with(curl_http_proxy, "socks5"))
 932                         curl_easy_setopt(result,
 933                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
 934                 else if (starts_with(curl_http_proxy, "socks4a"))
 935                         curl_easy_setopt(result,
 936                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
 937                 else if (starts_with(curl_http_proxy, "socks"))
 938                         curl_easy_setopt(result,
 939                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
 940 #endif
 941 #if LIBCURL_VERSION_NUM >= 0x073400
 942                 else if (starts_with(curl_http_proxy, "https"))
 943                         curl_easy_setopt(result,
 944                                 CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
 945 #endif
 946                 if (strstr(curl_http_proxy, "://"))
 947                         credential_from_url(&proxy_auth, curl_http_proxy);
 948                 else {
 949                         struct strbuf url = STRBUF_INIT;
 950                         strbuf_addf(&url, "http://%s", curl_http_proxy);
 951                         credential_from_url(&proxy_auth, url.buf);
 952                         strbuf_release(&url);
 953                 }
 954
 955                 if (!proxy_auth.host)
 956                         die("Invalid proxy URL '%s'", curl_http_proxy);
 957
 958                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
 959 #if LIBCURL_VERSION_NUM >= 0x071304
 960                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
 961                 var_override(&curl_no_proxy, getenv("no_proxy"));
 962                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
 963 #endif
 964         }
 965         init_curl_proxy_auth(result);
 966
 967         set_curl_keepalive(result);
 968
 969         return result;
 970 }
 971
 972 static void set_from_env(const char **var, const char *envname)
 973 {
 974         const char *val = getenv(envname);
 975         if (val)
 976                 *var = val;
 977 }
 978
 979 void http_init(struct remote *remote, const char *url, int proactive_auth)
 980 {
 981         char *low_speed_limit;
 982         char *low_speed_time;
 983         char *normalized_url;
 984         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
 985
 986         config.section = "http";
 987         config.key = NULL;
 988         config.collect_fn = http_options;
 989         config.cascade_fn = git_default_config;
 990         config.cb = NULL;
 991
 992         http_is_verbose = 0;
 993         normalized_url = url_normalize(url, &config.url);
 994
 995         git_config(urlmatch_config_entry, &config);
 996         free(normalized_url);
 997
 998         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
 999                 die("curl_global_init failed");
1000
1001         http_proactive_auth = proactive_auth;
1002
1003         if (remote && remote->http_proxy)
1004                 curl_http_proxy = xstrdup(remote->http_proxy);
1005
1006         if (remote)
1007                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
1008
1009         pragma_header = curl_slist_append(http_copy_default_headers(),
1010                 "Pragma: no-cache");
1011         no_pragma_header = curl_slist_append(http_copy_default_headers(),
1012                 "Pragma:");
1013
1014 #ifdef USE_CURL_MULTI
1015         {
1016                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
1017                 if (http_max_requests != NULL)
1018                         max_requests = atoi(http_max_requests);
1019         }
1020
1021         curlm = curl_multi_init();
1022         if (!curlm)
1023                 die("curl_multi_init failed");
1024 #endif
1025
1026         if (getenv("GIT_SSL_NO_VERIFY"))
1027                 curl_ssl_verify = 0;
1028
1029         set_from_env(&ssl_cert, "GIT_SSL_CERT");
1030 #if LIBCURL_VERSION_NUM >= 0x070903
1031         set_from_env(&ssl_key, "GIT_SSL_KEY");
1032 #endif
1033 #if LIBCURL_VERSION_NUM >= 0x070908
1034         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
1035 #endif
1036         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
1037
1038         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
1039
1040         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
1041         if (low_speed_limit != NULL)
1042                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
1043         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
1044         if (low_speed_time != NULL)
1045                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
1046
1047         if (curl_ssl_verify == -1)
1048                 curl_ssl_verify = 1;
1049
1050         curl_session_count = 0;
1051 #ifdef USE_CURL_MULTI
1052         if (max_requests < 1)
1053                 max_requests = DEFAULT_MAX_REQUESTS;
1054 #endif
1055
1056         if (getenv("GIT_CURL_FTP_NO_EPSV"))
1057                 curl_ftp_no_epsv = 1;
1058
1059         if (url) {
1060                 credential_from_url(&http_auth, url);
1061                 if (!ssl_cert_password_required &&
1062                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
1063                     starts_with(url, "https://"))
1064                         ssl_cert_password_required = 1;
1065         }
1066
1067 #ifndef NO_CURL_EASY_DUPHANDLE
1068         curl_default = get_curl_handle();
1069 #endif
1070 }
1071
1072 void http_cleanup(void)
1073 {
1074         struct active_request_slot *slot = active_queue_head;
1075
1076         while (slot != NULL) {
1077                 struct active_request_slot *next = slot->next;
1078                 if (slot->curl != NULL) {
1079                         xmulti_remove_handle(slot);
1080                         curl_easy_cleanup(slot->curl);
1081                 }
1082                 free(slot);
1083                 slot = next;
1084         }
1085         active_queue_head = NULL;
1086
1087 #ifndef NO_CURL_EASY_DUPHANDLE
1088         curl_easy_cleanup(curl_default);
1089 #endif
1090
1091 #ifdef USE_CURL_MULTI
1092         curl_multi_cleanup(curlm);
1093 #endif
1094         curl_global_cleanup();
1095
1096         curl_slist_free_all(extra_http_headers);
1097         extra_http_headers = NULL;
1098
1099         curl_slist_free_all(pragma_header);
1100         pragma_header = NULL;
1101
1102         curl_slist_free_all(no_pragma_header);
1103         no_pragma_header = NULL;
1104
1105         if (curl_http_proxy) {
1106                 free((void *)curl_http_proxy);
1107                 curl_http_proxy = NULL;
1108         }
1109
1110         if (proxy_auth.password) {
1111                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1112                 FREE_AND_NULL(proxy_auth.password);
1113         }
1114
1115         free((void *)curl_proxyuserpwd);
1116         curl_proxyuserpwd = NULL;
1117
1118         free((void *)http_proxy_authmethod);
1119         http_proxy_authmethod = NULL;
1120
1121         if (cert_auth.password != NULL) {
1122                 memset(cert_auth.password, 0, strlen(cert_auth.password));
1123                 FREE_AND_NULL(cert_auth.password);
1124         }
1125         ssl_cert_password_required = 0;
1126
1127         FREE_AND_NULL(cached_accept_language);
1128 }
1129
1130 struct active_request_slot *get_active_slot(void)
1131 {
1132         struct active_request_slot *slot = active_queue_head;
1133         struct active_request_slot *newslot;
1134
1135 #ifdef USE_CURL_MULTI
1136         int num_transfers;
1137
1138         /* Wait for a slot to open up if the queue is full */
1139         while (active_requests >= max_requests) {
1140                 curl_multi_perform(curlm, &num_transfers);
1141                 if (num_transfers < active_requests)
1142                         process_curl_messages();
1143         }
1144 #endif
1145
1146         while (slot != NULL && slot->in_use)
1147                 slot = slot->next;
1148
1149         if (slot == NULL) {
1150                 newslot = xmalloc(sizeof(*newslot));
1151                 newslot->curl = NULL;
1152                 newslot->in_use = 0;
1153                 newslot->next = NULL;
1154
1155                 slot = active_queue_head;
1156                 if (slot == NULL) {
1157                         active_queue_head = newslot;
1158                 } else {
1159                         while (slot->next != NULL)
1160                                 slot = slot->next;
1161                         slot->next = newslot;
1162                 }
1163                 slot = newslot;
1164         }
1165
1166         if (slot->curl == NULL) {
1167 #ifdef NO_CURL_EASY_DUPHANDLE
1168                 slot->curl = get_curl_handle();
1169 #else
1170                 slot->curl = curl_easy_duphandle(curl_default);
1171 #endif
1172                 curl_session_count++;
1173         }
1174
1175         active_requests++;
1176         slot->in_use = 1;
1177         slot->results = NULL;
1178         slot->finished = NULL;
1179         slot->callback_data = NULL;
1180         slot->callback_func = NULL;
1181         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1182         if (curl_save_cookies)
1183                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1184         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1185         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1186         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1187         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1188         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1189         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1190         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1191         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1192         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1193         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1194
1195         /*
1196          * Default following to off unless "ALWAYS" is configured; this gives
1197          * callers a sane starting point, and they can tweak for individual
1198          * HTTP_FOLLOW_* cases themselves.
1199          */
1200         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1201                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1202         else
1203                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1204
1205 #if LIBCURL_VERSION_NUM >= 0x070a08
1206         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1207 #endif
1208 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1209         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1210 #endif
1211         if (http_auth.password || curl_empty_auth_enabled())
1212                 init_curl_http_auth(slot->curl);
1213
1214         return slot;
1215 }
1216
1217 int start_active_slot(struct active_request_slot *slot)
1218 {
1219 #ifdef USE_CURL_MULTI
1220         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1221         int num_transfers;
1222
1223         if (curlm_result != CURLM_OK &&
1224             curlm_result != CURLM_CALL_MULTI_PERFORM) {
1225                 warning("curl_multi_add_handle failed: %s",
1226                         curl_multi_strerror(curlm_result));
1227                 active_requests--;
1228                 slot->in_use = 0;
1229                 return 0;
1230         }
1231
1232         /*
1233          * We know there must be something to do, since we just added
1234          * something.
1235          */
1236         curl_multi_perform(curlm, &num_transfers);
1237 #endif
1238         return 1;
1239 }
1240
1241 #ifdef USE_CURL_MULTI
1242 struct fill_chain {
1243         void *data;
1244         int (*fill)(void *);
1245         struct fill_chain *next;
1246 };
1247
1248 static struct fill_chain *fill_cfg;
1249
1250 void add_fill_function(void *data, int (*fill)(void *))
1251 {
1252         struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
1253         struct fill_chain **linkp = &fill_cfg;
1254         new_fill->data = data;
1255         new_fill->fill = fill;
1256         new_fill->next = NULL;
1257         while (*linkp)
1258                 linkp = &(*linkp)->next;
1259         *linkp = new_fill;
1260 }
1261
1262 void fill_active_slots(void)
1263 {
1264         struct active_request_slot *slot = active_queue_head;
1265
1266         while (active_requests < max_requests) {
1267                 struct fill_chain *fill;
1268                 for (fill = fill_cfg; fill; fill = fill->next)
1269                         if (fill->fill(fill->data))
1270                                 break;
1271
1272                 if (!fill)
1273                         break;
1274         }
1275
1276         while (slot != NULL) {
1277                 if (!slot->in_use && slot->curl != NULL
1278                         && curl_session_count > min_curl_sessions) {
1279                         curl_easy_cleanup(slot->curl);
1280                         slot->curl = NULL;
1281                         curl_session_count--;
1282                 }
1283                 slot = slot->next;
1284         }
1285 }
1286
1287 void step_active_slots(void)
1288 {
1289         int num_transfers;
1290         CURLMcode curlm_result;
1291
1292         do {
1293                 curlm_result = curl_multi_perform(curlm, &num_transfers);
1294         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1295         if (num_transfers < active_requests) {
1296                 process_curl_messages();
1297                 fill_active_slots();
1298         }
1299 }
1300 #endif
1301
1302 void run_active_slot(struct active_request_slot *slot)
1303 {
1304 #ifdef USE_CURL_MULTI
1305         fd_set readfds;
1306         fd_set writefds;
1307         fd_set excfds;
1308         int max_fd;
1309         struct timeval select_timeout;
1310         int finished = 0;
1311
1312         slot->finished = &finished;
1313         while (!finished) {
1314                 step_active_slots();
1315
1316                 if (slot->in_use) {
1317 #if LIBCURL_VERSION_NUM >= 0x070f04
1318                         long curl_timeout;
1319                         curl_multi_timeout(curlm, &curl_timeout);
1320                         if (curl_timeout == 0) {
1321                                 continue;
1322                         } else if (curl_timeout == -1) {
1323                                 select_timeout.tv_sec  = 0;
1324                                 select_timeout.tv_usec = 50000;
1325                         } else {
1326                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1327                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1328                         }
1329 #else
1330                         select_timeout.tv_sec  = 0;
1331                         select_timeout.tv_usec = 50000;
1332 #endif
1333
1334                         max_fd = -1;
1335                         FD_ZERO(&readfds);
1336                         FD_ZERO(&writefds);
1337                         FD_ZERO(&excfds);
1338                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1339
1340                         /*
1341                          * It can happen that curl_multi_timeout returns a pathologically
1342                          * long timeout when curl_multi_fdset returns no file descriptors
1343                          * to read.  See commit message for more details.
1344                          */
1345                         if (max_fd < 0 &&
1346                             (select_timeout.tv_sec > 0 ||
1347                              select_timeout.tv_usec > 50000)) {
1348                                 select_timeout.tv_sec  = 0;
1349                                 select_timeout.tv_usec = 50000;
1350                         }
1351
1352                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1353                 }
1354         }
1355 #else
1356         while (slot->in_use) {
1357                 slot->curl_result = curl_easy_perform(slot->curl);
1358                 finish_active_slot(slot);
1359         }
1360 #endif
1361 }
1362
1363 static void release_active_slot(struct active_request_slot *slot)
1364 {
1365         closedown_active_slot(slot);
1366         if (slot->curl) {
1367                 xmulti_remove_handle(slot);
1368                 if (curl_session_count > min_curl_sessions) {
1369                         curl_easy_cleanup(slot->curl);
1370                         slot->curl = NULL;
1371                         curl_session_count--;
1372                 }
1373         }
1374 #ifdef USE_CURL_MULTI
1375         fill_active_slots();
1376 #endif
1377 }
1378
1379 void finish_all_active_slots(void)
1380 {
1381         struct active_request_slot *slot = active_queue_head;
1382
1383         while (slot != NULL)
1384                 if (slot->in_use) {
1385                         run_active_slot(slot);
1386                         slot = active_queue_head;
1387                 } else {
1388                         slot = slot->next;
1389                 }
1390 }
1391
1392 /* Helpers for modifying and creating URLs */
1393 static inline int needs_quote(int ch)
1394 {
1395         if (((ch >= 'A') && (ch <= 'Z'))
1396                         || ((ch >= 'a') && (ch <= 'z'))
1397                         || ((ch >= '0') && (ch <= '9'))
1398                         || (ch == '/')
1399                         || (ch == '-')
1400                         || (ch == '.'))
1401                 return 0;
1402         return 1;
1403 }
1404
1405 static char *quote_ref_url(const char *base, const char *ref)
1406 {
1407         struct strbuf buf = STRBUF_INIT;
1408         const char *cp;
1409         int ch;
1410
1411         end_url_with_slash(&buf, base);
1412
1413         for (cp = ref; (ch = *cp) != 0; cp++)
1414                 if (needs_quote(ch))
1415                         strbuf_addf(&buf, "%%%02x", ch);
1416                 else
1417                         strbuf_addch(&buf, *cp);
1418
1419         return strbuf_detach(&buf, NULL);
1420 }
1421
1422 void append_remote_object_url(struct strbuf *buf, const char *url,
1423                               const char *hex,
1424                               int only_two_digit_prefix)
1425 {
1426         end_url_with_slash(buf, url);
1427
1428         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1429         if (!only_two_digit_prefix)
1430                 strbuf_addstr(buf, hex + 2);
1431 }
1432
1433 char *get_remote_object_url(const char *url, const char *hex,
1434                             int only_two_digit_prefix)
1435 {
1436         struct strbuf buf = STRBUF_INIT;
1437         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1438         return strbuf_detach(&buf, NULL);
1439 }
1440
1441 static int handle_curl_result(struct slot_results *results)
1442 {
1443         /*
1444          * If we see a failing http code with CURLE_OK, we have turned off
1445          * FAILONERROR (to keep the server's custom error response), and should
1446          * translate the code into failure here.
1447          *
1448          * Likewise, if we see a redirect (30x code), that means we turned off
1449          * redirect-following, and we should treat the result as an error.
1450          */
1451         if (results->curl_result == CURLE_OK &&
1452             results->http_code >= 300) {
1453                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
1454                 /*
1455                  * Normally curl will already have put the "reason phrase"
1456                  * from the server into curl_errorstr; unfortunately without
1457                  * FAILONERROR it is lost, so we can give only the numeric
1458                  * status code.
1459                  */
1460                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1461                           "The requested URL returned error: %ld",
1462                           results->http_code);
1463         }
1464
1465         if (results->curl_result == CURLE_OK) {
1466                 credential_approve(&http_auth);
1467                 if (proxy_auth.password)
1468                         credential_approve(&proxy_auth);
1469                 return HTTP_OK;
1470         } else if (missing_target(results))
1471                 return HTTP_MISSING_TARGET;
1472         else if (results->http_code == 401) {
1473                 if (http_auth.username && http_auth.password) {
1474                         credential_reject(&http_auth);
1475                         return HTTP_NOAUTH;
1476                 } else {
1477 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1478                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1479                         if (results->auth_avail) {
1480                                 http_auth_methods &= results->auth_avail;
1481                                 http_auth_methods_restricted = 1;
1482                         }
1483 #endif
1484                         return HTTP_REAUTH;
1485                 }
1486         } else {
1487                 if (results->http_connectcode == 407)
1488                         credential_reject(&proxy_auth);
1489 #if LIBCURL_VERSION_NUM >= 0x070c00
1490                 if (!curl_errorstr[0])
1491                         strlcpy(curl_errorstr,
1492                                 curl_easy_strerror(results->curl_result),
1493                                 sizeof(curl_errorstr));
1494 #endif
1495                 return HTTP_ERROR;
1496         }
1497 }
1498
1499 int run_one_slot(struct active_request_slot *slot,
1500                  struct slot_results *results)
1501 {
1502         slot->results = results;
1503         if (!start_active_slot(slot)) {
1504                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1505                           "failed to start HTTP request");
1506                 return HTTP_START_FAILED;
1507         }
1508
1509         run_active_slot(slot);
1510         return handle_curl_result(results);
1511 }
1512
1513 struct curl_slist *http_copy_default_headers(void)
1514 {
1515         struct curl_slist *headers = NULL, *h;
1516
1517         for (h = extra_http_headers; h; h = h->next)
1518                 headers = curl_slist_append(headers, h->data);
1519
1520         return headers;
1521 }
1522
1523 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1524 {
1525         char *ptr;
1526         CURLcode ret;
1527
1528         strbuf_reset(buf);
1529         ret = curl_easy_getinfo(curl, info, &ptr);
1530         if (!ret && ptr)
1531                 strbuf_addstr(buf, ptr);
1532         return ret;
1533 }
1534
1535 /*
1536  * Check for and extract a content-type parameter. "raw"
1537  * should be positioned at the start of the potential
1538  * parameter, with any whitespace already removed.
1539  *
1540  * "name" is the name of the parameter. The value is appended
1541  * to "out".
1542  */
1543 static int extract_param(const char *raw, const char *name,
1544                          struct strbuf *out)
1545 {
1546         size_t len = strlen(name);
1547
1548         if (strncasecmp(raw, name, len))
1549                 return -1;
1550         raw += len;
1551
1552         if (*raw != '=')
1553                 return -1;
1554         raw++;
1555
1556         while (*raw && !isspace(*raw) && *raw != ';')
1557                 strbuf_addch(out, *raw++);
1558         return 0;
1559 }
1560
1561 /*
1562  * Extract a normalized version of the content type, with any
1563  * spaces suppressed, all letters lowercased, and no trailing ";"
1564  * or parameters.
1565  *
1566  * Note that we will silently remove even invalid whitespace. For
1567  * example, "text / plain" is specifically forbidden by RFC 2616,
1568  * but "text/plain" is the only reasonable output, and this keeps
1569  * our code simple.
1570  *
1571  * If the "charset" argument is not NULL, store the value of any
1572  * charset parameter there.
1573  *
1574  * Example:
1575  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1576  *   "text / plain" -> "text/plain"
1577  */
1578 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1579                                  struct strbuf *charset)
1580 {
1581         const char *p;
1582
1583         strbuf_reset(type);
1584         strbuf_grow(type, raw->len);
1585         for (p = raw->buf; *p; p++) {
1586                 if (isspace(*p))
1587                         continue;
1588                 if (*p == ';') {
1589                         p++;
1590                         break;
1591                 }
1592                 strbuf_addch(type, tolower(*p));
1593         }
1594
1595         if (!charset)
1596                 return;
1597
1598         strbuf_reset(charset);
1599         while (*p) {
1600                 while (isspace(*p) || *p == ';')
1601                         p++;
1602                 if (!extract_param(p, "charset", charset))
1603                         return;
1604                 while (*p && !isspace(*p))
1605                         p++;
1606         }
1607
1608         if (!charset->len && starts_with(type->buf, "text/"))
1609                 strbuf_addstr(charset, "ISO-8859-1");
1610 }
1611
1612 static void write_accept_language(struct strbuf *buf)
1613 {
1614         /*
1615          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1616          * that, q-value will be smaller than 0.001, the minimum q-value the
1617          * HTTP specification allows. See
1618          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1619          */
1620         const int MAX_DECIMAL_PLACES = 3;
1621         const int MAX_LANGUAGE_TAGS = 1000;
1622         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1623         char **language_tags = NULL;
1624         int num_langs = 0;
1625         const char *s = get_preferred_languages();
1626         int i;
1627         struct strbuf tag = STRBUF_INIT;
1628
1629         /* Don't add Accept-Language header if no language is preferred. */
1630         if (!s)
1631                 return;
1632
1633         /*
1634          * Split the colon-separated string of preferred languages into
1635          * language_tags array.
1636          */
1637         do {
1638                 /* collect language tag */
1639                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1640                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1641
1642                 /* skip .codeset, @modifier and any other unnecessary parts */
1643                 while (*s && *s != ':')
1644                         s++;
1645
1646                 if (tag.len) {
1647                         num_langs++;
1648                         REALLOC_ARRAY(language_tags, num_langs);
1649                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1650                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1651                                 break;
1652                 }
1653         } while (*s++);
1654
1655         /* write Accept-Language header into buf */
1656         if (num_langs) {
1657                 int last_buf_len = 0;
1658                 int max_q;
1659                 int decimal_places;
1660                 char q_format[32];
1661
1662                 /* add '*' */
1663                 REALLOC_ARRAY(language_tags, num_langs + 1);
1664                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1665
1666                 /* compute decimal_places */
1667                 for (max_q = 1, decimal_places = 0;
1668                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1669                      decimal_places++, max_q *= 10)
1670                         ;
1671
1672                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1673
1674                 strbuf_addstr(buf, "Accept-Language: ");
1675
1676                 for (i = 0; i < num_langs; i++) {
1677                         if (i > 0)
1678                                 strbuf_addstr(buf, ", ");
1679
1680                         strbuf_addstr(buf, language_tags[i]);
1681
1682                         if (i > 0)
1683                                 strbuf_addf(buf, q_format, max_q - i);
1684
1685                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1686                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1687                                 break;
1688                         }
1689
1690                         last_buf_len = buf->len;
1691                 }
1692         }
1693
1694         /* free language tags -- last one is a static '*' */
1695         for (i = 0; i < num_langs - 1; i++)
1696                 free(language_tags[i]);
1697         free(language_tags);
1698 }
1699
1700 /*
1701  * Get an Accept-Language header which indicates user's preferred languages.
1702  *
1703  * Examples:
1704  *   LANGUAGE= -> ""
1705  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1706  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1707  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1708  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1709  *   LANGUAGE= LANG=C -> ""
1710  */
1711 static const char *get_accept_language(void)
1712 {
1713         if (!cached_accept_language) {
1714                 struct strbuf buf = STRBUF_INIT;
1715                 write_accept_language(&buf);
1716                 if (buf.len > 0)
1717                         cached_accept_language = strbuf_detach(&buf, NULL);
1718         }
1719
1720         return cached_accept_language;
1721 }
1722
1723 static void http_opt_request_remainder(CURL *curl, off_t pos)
1724 {
1725         char buf[128];
1726         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1727         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1728 }
1729
1730 /* http_request() targets */
1731 #define HTTP_REQUEST_STRBUF     0
1732 #define HTTP_REQUEST_FILE       1
1733
1734 static int http_request(const char *url,
1735                         void *result, int target,
1736                         const struct http_get_options *options)
1737 {
1738         struct active_request_slot *slot;
1739         struct slot_results results;
1740         struct curl_slist *headers = http_copy_default_headers();
1741         struct strbuf buf = STRBUF_INIT;
1742         const char *accept_language;
1743         int ret;
1744
1745         slot = get_active_slot();
1746         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1747
1748         if (result == NULL) {
1749                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1750         } else {
1751                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1752                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1753
1754                 if (target == HTTP_REQUEST_FILE) {
1755                         off_t posn = ftello(result);
1756                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1757                                          fwrite);
1758                         if (posn > 0)
1759                                 http_opt_request_remainder(slot->curl, posn);
1760                 } else
1761                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1762                                          fwrite_buffer);
1763         }
1764
1765         accept_language = get_accept_language();
1766
1767         if (accept_language)
1768                 headers = curl_slist_append(headers, accept_language);
1769
1770         strbuf_addstr(&buf, "Pragma:");
1771         if (options && options->no_cache)
1772                 strbuf_addstr(&buf, " no-cache");
1773         if (options && options->keep_error)
1774                 curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1775         if (options && options->initial_request &&
1776             http_follow_config == HTTP_FOLLOW_INITIAL)
1777                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1778
1779         headers = curl_slist_append(headers, buf.buf);
1780
1781         /* Add additional headers here */
1782         if (options && options->extra_headers) {
1783                 const struct string_list_item *item;
1784                 for_each_string_list_item(item, options->extra_headers) {
1785                         headers = curl_slist_append(headers, item->string);
1786                 }
1787         }
1788
1789         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1790         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1791         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
1792
1793         ret = run_one_slot(slot, &results);
1794
1795         if (options && options->content_type) {
1796                 struct strbuf raw = STRBUF_INIT;
1797                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1798                 extract_content_type(&raw, options->content_type,
1799                                      options->charset);
1800                 strbuf_release(&raw);
1801         }
1802
1803         if (options && options->effective_url)
1804                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1805                                 options->effective_url);
1806
1807         curl_slist_free_all(headers);
1808         strbuf_release(&buf);
1809
1810         return ret;
1811 }
1812
1813 /*
1814  * Update the "base" url to a more appropriate value, as deduced by
1815  * redirects seen when requesting a URL starting with "url".
1816  *
1817  * The "asked" parameter is a URL that we asked curl to access, and must begin
1818  * with "base".
1819  *
1820  * The "got" parameter is the URL that curl reported to us as where we ended
1821  * up.
1822  *
1823  * Returns 1 if we updated the base url, 0 otherwise.
1824  *
1825  * Our basic strategy is to compare "base" and "asked" to find the bits
1826  * specific to our request. We then strip those bits off of "got" to yield the
1827  * new base. So for example, if our base is "http://example.com/foo.git",
1828  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1829  * with "https://other.example.com/foo.git/info/refs". We would want the
1830  * new URL to become "https://other.example.com/foo.git".
1831  *
1832  * Note that this assumes a sane redirect scheme. It's entirely possible
1833  * in the example above to end up at a URL that does not even end in
1834  * "info/refs".  In such a case we die. There's not much we can do, such a
1835  * scheme is unlikely to represent a real git repository, and failing to
1836  * rewrite the base opens options for malicious redirects to do funny things.
1837  */
1838 static int update_url_from_redirect(struct strbuf *base,
1839                                     const char *asked,
1840                                     const struct strbuf *got)
1841 {
1842         const char *tail;
1843         size_t new_len;
1844
1845         if (!strcmp(asked, got->buf))
1846                 return 0;
1847
1848         if (!skip_prefix(asked, base->buf, &tail))
1849                 BUG("update_url_from_redirect: %s is not a superset of %s",
1850                     asked, base->buf);
1851
1852         new_len = got->len;
1853         if (!strip_suffix_mem(got->buf, &new_len, tail))
1854                 die(_("unable to update url base from redirection:\n"
1855                       "  asked for: %s\n"
1856                       "   redirect: %s"),
1857                     asked, got->buf);
1858
1859         strbuf_reset(base);
1860         strbuf_add(base, got->buf, new_len);
1861
1862         return 1;
1863 }
1864
1865 static int http_request_reauth(const char *url,
1866                                void *result, int target,
1867                                struct http_get_options *options)
1868 {
1869         int ret = http_request(url, result, target, options);
1870
1871         if (ret != HTTP_OK && ret != HTTP_REAUTH)
1872                 return ret;
1873
1874         if (options && options->effective_url && options->base_url) {
1875                 if (update_url_from_redirect(options->base_url,
1876                                              url, options->effective_url)) {
1877                         credential_from_url(&http_auth, options->base_url->buf);
1878                         url = options->effective_url->buf;
1879                 }
1880         }
1881
1882         if (ret != HTTP_REAUTH)
1883                 return ret;
1884
1885         /*
1886          * If we are using KEEP_ERROR, the previous request may have
1887          * put cruft into our output stream; we should clear it out before
1888          * making our next request. We only know how to do this for
1889          * the strbuf case, but that is enough to satisfy current callers.
1890          */
1891         if (options && options->keep_error) {
1892                 switch (target) {
1893                 case HTTP_REQUEST_STRBUF:
1894                         strbuf_reset(result);
1895                         break;
1896                 default:
1897                         BUG("HTTP_KEEP_ERROR is only supported with strbufs");
1898                 }
1899         }
1900
1901         credential_fill(&http_auth);
1902
1903         return http_request(url, result, target, options);
1904 }
1905
1906 int http_get_strbuf(const char *url,
1907                     struct strbuf *result,
1908                     struct http_get_options *options)
1909 {
1910         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
1911 }
1912
1913 /*
1914  * Downloads a URL and stores the result in the given file.
1915  *
1916  * If a previous interrupted download is detected (i.e. a previous temporary
1917  * file is still around) the download is resumed.
1918  */
1919 static int http_get_file(const char *url, const char *filename,
1920                          struct http_get_options *options)
1921 {
1922         int ret;
1923         struct strbuf tmpfile = STRBUF_INIT;
1924         FILE *result;
1925
1926         strbuf_addf(&tmpfile, "%s.temp", filename);
1927         result = fopen(tmpfile.buf, "a");
1928         if (!result) {
1929                 error("Unable to open local file %s", tmpfile.buf);
1930                 ret = HTTP_ERROR;
1931                 goto cleanup;
1932         }
1933
1934         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
1935         fclose(result);
1936
1937         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
1938                 ret = HTTP_ERROR;
1939 cleanup:
1940         strbuf_release(&tmpfile);
1941         return ret;
1942 }
1943
1944 int http_fetch_ref(const char *base, struct ref *ref)
1945 {
1946         struct http_get_options options = {0};
1947         char *url;
1948         struct strbuf buffer = STRBUF_INIT;
1949         int ret = -1;
1950
1951         options.no_cache = 1;
1952
1953         url = quote_ref_url(base, ref->name);
1954         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
1955                 strbuf_rtrim(&buffer);
1956                 if (buffer.len == 40)
1957                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
1958                 else if (starts_with(buffer.buf, "ref: ")) {
1959                         ref->symref = xstrdup(buffer.buf + 5);
1960                         ret = 0;
1961                 }
1962         }
1963
1964         strbuf_release(&buffer);
1965         free(url);
1966         return ret;
1967 }
1968
1969 /* Helpers for fetching packs */
1970 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
1971 {
1972         char *url, *tmp;
1973         struct strbuf buf = STRBUF_INIT;
1974
1975         if (http_is_verbose)
1976                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
1977
1978         end_url_with_slash(&buf, base_url);
1979         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
1980         url = strbuf_detach(&buf, NULL);
1981
1982         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
1983         tmp = strbuf_detach(&buf, NULL);
1984
1985         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
1986                 error("Unable to get pack index %s", url);
1987                 FREE_AND_NULL(tmp);
1988         }
1989
1990         free(url);
1991         return tmp;
1992 }
1993
1994 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
1995         unsigned char *sha1, const char *base_url)
1996 {
1997         struct packed_git *new_pack;
1998         char *tmp_idx = NULL;
1999         int ret;
2000
2001         if (has_pack_index(sha1)) {
2002                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
2003                 if (!new_pack)
2004                         return -1; /* parse_pack_index() already issued error message */
2005                 goto add_pack;
2006         }
2007
2008         tmp_idx = fetch_pack_index(sha1, base_url);
2009         if (!tmp_idx)
2010                 return -1;
2011
2012         new_pack = parse_pack_index(sha1, tmp_idx);
2013         if (!new_pack) {
2014                 unlink(tmp_idx);
2015                 free(tmp_idx);
2016
2017                 return -1; /* parse_pack_index() already issued error message */
2018         }
2019
2020         ret = verify_pack_index(new_pack);
2021         if (!ret) {
2022                 close_pack_index(new_pack);
2023                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
2024         }
2025         free(tmp_idx);
2026         if (ret)
2027                 return -1;
2028
2029 add_pack:
2030         new_pack->next = *packs_head;
2031         *packs_head = new_pack;
2032         return 0;
2033 }
2034
2035 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
2036 {
2037         struct http_get_options options = {0};
2038         int ret = 0, i = 0;
2039         char *url, *data;
2040         struct strbuf buf = STRBUF_INIT;
2041         unsigned char hash[GIT_MAX_RAWSZ];
2042         const unsigned hexsz = the_hash_algo->hexsz;
2043
2044         end_url_with_slash(&buf, base_url);
2045         strbuf_addstr(&buf, "objects/info/packs");
2046         url = strbuf_detach(&buf, NULL);
2047
2048         options.no_cache = 1;
2049         ret = http_get_strbuf(url, &buf, &options);
2050         if (ret != HTTP_OK)
2051                 goto cleanup;
2052
2053         data = buf.buf;
2054         while (i < buf.len) {
2055                 switch (data[i]) {
2056                 case 'P':
2057                         i++;
2058                         if (i + hexsz + 12 <= buf.len &&
2059                             starts_with(data + i, " pack-") &&
2060                             starts_with(data + i + hexsz + 6, ".pack\n")) {
2061                                 get_sha1_hex(data + i + 6, hash);
2062                                 fetch_and_setup_pack_index(packs_head, hash,
2063                                                       base_url);
2064                                 i += hexsz + 11;
2065                                 break;
2066                         }
2067                 default:
2068                         while (i < buf.len && data[i] != '\n')
2069                                 i++;
2070                 }
2071                 i++;
2072         }
2073
2074 cleanup:
2075         free(url);
2076         return ret;
2077 }
2078
2079 void release_http_pack_request(struct http_pack_request *preq)
2080 {
2081         if (preq->packfile != NULL) {
2082                 fclose(preq->packfile);
2083                 preq->packfile = NULL;
2084         }
2085         preq->slot = NULL;
2086         strbuf_release(&preq->tmpfile);
2087         free(preq->url);
2088         free(preq);
2089 }
2090
2091 int finish_http_pack_request(struct http_pack_request *preq)
2092 {
2093         struct packed_git **lst;
2094         struct packed_git *p = preq->target;
2095         char *tmp_idx;
2096         size_t len;
2097         struct child_process ip = CHILD_PROCESS_INIT;
2098
2099         close_pack_index(p);
2100
2101         fclose(preq->packfile);
2102         preq->packfile = NULL;
2103
2104         lst = preq->lst;
2105         while (*lst != p)
2106                 lst = &((*lst)->next);
2107         *lst = (*lst)->next;
2108
2109         if (!strip_suffix(preq->tmpfile.buf, ".pack.temp", &len))
2110                 BUG("pack tmpfile does not end in .pack.temp?");
2111         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile.buf);
2112
2113         argv_array_push(&ip.args, "index-pack");
2114         argv_array_pushl(&ip.args, "-o", tmp_idx, NULL);
2115         argv_array_push(&ip.args, preq->tmpfile.buf);
2116         ip.git_cmd = 1;
2117         ip.no_stdin = 1;
2118         ip.no_stdout = 1;
2119
2120         if (run_command(&ip)) {
2121                 unlink(preq->tmpfile.buf);
2122                 unlink(tmp_idx);
2123                 free(tmp_idx);
2124                 return -1;
2125         }
2126
2127         unlink(sha1_pack_index_name(p->sha1));
2128
2129         if (finalize_object_file(preq->tmpfile.buf, sha1_pack_name(p->sha1))
2130          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
2131                 free(tmp_idx);
2132                 return -1;
2133         }
2134
2135         install_packed_git(the_repository, p);
2136         free(tmp_idx);
2137         return 0;
2138 }
2139
2140 struct http_pack_request *new_http_pack_request(
2141         struct packed_git *target, const char *base_url)
2142 {
2143         off_t prev_posn = 0;
2144         struct strbuf buf = STRBUF_INIT;
2145         struct http_pack_request *preq;
2146
2147         preq = xcalloc(1, sizeof(*preq));
2148         strbuf_init(&preq->tmpfile, 0);
2149         preq->target = target;
2150
2151         end_url_with_slash(&buf, base_url);
2152         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
2153                 sha1_to_hex(target->sha1));
2154         preq->url = strbuf_detach(&buf, NULL);
2155
2156         strbuf_addf(&preq->tmpfile, "%s.temp", sha1_pack_name(target->sha1));
2157         preq->packfile = fopen(preq->tmpfile.buf, "a");
2158         if (!preq->packfile) {
2159                 error("Unable to open local file %s for pack",
2160                       preq->tmpfile.buf);
2161                 goto abort;
2162         }
2163
2164         preq->slot = get_active_slot();
2165         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
2166         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
2167         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
2168         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
2169                 no_pragma_header);
2170
2171         /*
2172          * If there is data present from a previous transfer attempt,
2173          * resume where it left off
2174          */
2175         prev_posn = ftello(preq->packfile);
2176         if (prev_posn>0) {
2177                 if (http_is_verbose)
2178                         fprintf(stderr,
2179                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
2180                                 sha1_to_hex(target->sha1), (uintmax_t)prev_posn);
2181                 http_opt_request_remainder(preq->slot->curl, prev_posn);
2182         }
2183
2184         return preq;
2185
2186 abort:
2187         strbuf_release(&preq->tmpfile);
2188         free(preq->url);
2189         free(preq);
2190         return NULL;
2191 }
2192
2193 /* Helpers for fetching objects (loose) */
2194 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
2195                                void *data)
2196 {
2197         unsigned char expn[4096];
2198         size_t size = eltsize * nmemb;
2199         int posn = 0;
2200         struct http_object_request *freq = data;
2201         struct active_request_slot *slot = freq->slot;
2202
2203         if (slot) {
2204                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
2205                                                 &slot->http_code);
2206                 if (c != CURLE_OK)
2207                         BUG("curl_easy_getinfo for HTTP code failed: %s",
2208                                 curl_easy_strerror(c));
2209                 if (slot->http_code >= 300)
2210                         return size;
2211         }
2212
2213         do {
2214                 ssize_t retval = xwrite(freq->localfile,
2215                                         (char *) ptr + posn, size - posn);
2216                 if (retval < 0)
2217                         return posn;
2218                 posn += retval;
2219         } while (posn < size);
2220
2221         freq->stream.avail_in = size;
2222         freq->stream.next_in = (void *)ptr;
2223         do {
2224                 freq->stream.next_out = expn;
2225                 freq->stream.avail_out = sizeof(expn);
2226                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
2227                 git_SHA1_Update(&freq->c, expn,
2228                                 sizeof(expn) - freq->stream.avail_out);
2229         } while (freq->stream.avail_in && freq->zret == Z_OK);
2230         return size;
2231 }
2232
2233 struct http_object_request *new_http_object_request(const char *base_url,
2234         unsigned char *sha1)
2235 {
2236         char *hex = sha1_to_hex(sha1);
2237         struct strbuf filename = STRBUF_INIT;
2238         struct strbuf prevfile = STRBUF_INIT;
2239         int prevlocal;
2240         char prev_buf[PREV_BUF_SIZE];
2241         ssize_t prev_read = 0;
2242         off_t prev_posn = 0;
2243         struct http_object_request *freq;
2244
2245         freq = xcalloc(1, sizeof(*freq));
2246         strbuf_init(&freq->tmpfile, 0);
2247         hashcpy(freq->sha1, sha1);
2248         freq->localfile = -1;
2249
2250         sha1_file_name(the_repository, &filename, sha1);
2251         strbuf_addf(&freq->tmpfile, "%s.temp", filename.buf);
2252
2253         strbuf_addf(&prevfile, "%s.prev", filename.buf);
2254         unlink_or_warn(prevfile.buf);
2255         rename(freq->tmpfile.buf, prevfile.buf);
2256         unlink_or_warn(freq->tmpfile.buf);
2257         strbuf_release(&filename);
2258
2259         if (freq->localfile != -1)
2260                 error("fd leakage in start: %d", freq->localfile);
2261         freq->localfile = open(freq->tmpfile.buf,
2262                                O_WRONLY | O_CREAT | O_EXCL, 0666);
2263         /*
2264          * This could have failed due to the "lazy directory creation";
2265          * try to mkdir the last path component.
2266          */
2267         if (freq->localfile < 0 && errno == ENOENT) {
2268                 char *dir = strrchr(freq->tmpfile.buf, '/');
2269                 if (dir) {
2270                         *dir = 0;
2271                         mkdir(freq->tmpfile.buf, 0777);
2272                         *dir = '/';
2273                 }
2274                 freq->localfile = open(freq->tmpfile.buf,
2275                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
2276         }
2277
2278         if (freq->localfile < 0) {
2279                 error_errno("Couldn't create temporary file %s",
2280                             freq->tmpfile.buf);
2281                 goto abort;
2282         }
2283
2284         git_inflate_init(&freq->stream);
2285
2286         git_SHA1_Init(&freq->c);
2287
2288         freq->url = get_remote_object_url(base_url, hex, 0);
2289
2290         /*
2291          * If a previous temp file is present, process what was already
2292          * fetched.
2293          */
2294         prevlocal = open(prevfile.buf, O_RDONLY);
2295         if (prevlocal != -1) {
2296                 do {
2297                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
2298                         if (prev_read>0) {
2299                                 if (fwrite_sha1_file(prev_buf,
2300                                                      1,
2301                                                      prev_read,
2302                                                      freq) == prev_read) {
2303                                         prev_posn += prev_read;
2304                                 } else {
2305                                         prev_read = -1;
2306                                 }
2307                         }
2308                 } while (prev_read > 0);
2309                 close(prevlocal);
2310         }
2311         unlink_or_warn(prevfile.buf);
2312         strbuf_release(&prevfile);
2313
2314         /*
2315          * Reset inflate/SHA1 if there was an error reading the previous temp
2316          * file; also rewind to the beginning of the local file.
2317          */
2318         if (prev_read == -1) {
2319                 memset(&freq->stream, 0, sizeof(freq->stream));
2320                 git_inflate_init(&freq->stream);
2321                 git_SHA1_Init(&freq->c);
2322                 if (prev_posn>0) {
2323                         prev_posn = 0;
2324                         lseek(freq->localfile, 0, SEEK_SET);
2325                         if (ftruncate(freq->localfile, 0) < 0) {
2326                                 error_errno("Couldn't truncate temporary file %s",
2327                                             freq->tmpfile.buf);
2328                                 goto abort;
2329                         }
2330                 }
2331         }
2332
2333         freq->slot = get_active_slot();
2334
2335         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2336         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2337         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2338         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2339         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2340         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2341
2342         /*
2343          * If we have successfully processed data from a previous fetch
2344          * attempt, only fetch the data we don't already have.
2345          */
2346         if (prev_posn>0) {
2347                 if (http_is_verbose)
2348                         fprintf(stderr,
2349                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2350                                 hex, (uintmax_t)prev_posn);
2351                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2352         }
2353
2354         return freq;
2355
2356 abort:
2357         strbuf_release(&prevfile);
2358         free(freq->url);
2359         free(freq);
2360         return NULL;
2361 }
2362
2363 void process_http_object_request(struct http_object_request *freq)
2364 {
2365         if (freq->slot == NULL)
2366                 return;
2367         freq->curl_result = freq->slot->curl_result;
2368         freq->http_code = freq->slot->http_code;
2369         freq->slot = NULL;
2370 }
2371
2372 int finish_http_object_request(struct http_object_request *freq)
2373 {
2374         struct stat st;
2375         struct strbuf filename = STRBUF_INIT;
2376
2377         close(freq->localfile);
2378         freq->localfile = -1;
2379
2380         process_http_object_request(freq);
2381
2382         if (freq->http_code == 416) {
2383                 warning("requested range invalid; we may already have all the data.");
2384         } else if (freq->curl_result != CURLE_OK) {
2385                 if (stat(freq->tmpfile.buf, &st) == 0)
2386                         if (st.st_size == 0)
2387                                 unlink_or_warn(freq->tmpfile.buf);
2388                 return -1;
2389         }
2390
2391         git_inflate_end(&freq->stream);
2392         git_SHA1_Final(freq->real_sha1, &freq->c);
2393         if (freq->zret != Z_STREAM_END) {
2394                 unlink_or_warn(freq->tmpfile.buf);
2395                 return -1;
2396         }
2397         if (hashcmp(freq->sha1, freq->real_sha1)) {
2398                 unlink_or_warn(freq->tmpfile.buf);
2399                 return -1;
2400         }
2401         sha1_file_name(the_repository, &filename, freq->sha1);
2402         freq->rename = finalize_object_file(freq->tmpfile.buf, filename.buf);
2403         strbuf_release(&filename);
2404
2405         return freq->rename;
2406 }
2407
2408 void abort_http_object_request(struct http_object_request *freq)
2409 {
2410         unlink_or_warn(freq->tmpfile.buf);
2411
2412         release_http_object_request(freq);
2413 }
2414
2415 void release_http_object_request(struct http_object_request *freq)
2416 {
2417         if (freq->localfile != -1) {
2418                 close(freq->localfile);
2419                 freq->localfile = -1;
2420         }
2421         if (freq->url != NULL) {
2422                 FREE_AND_NULL(freq->url);
2423         }
2424         if (freq->slot != NULL) {
2425                 freq->slot->callback_func = NULL;
2426                 freq->slot->callback_data = NULL;
2427                 release_active_slot(freq->slot);
2428                 freq->slot = NULL;
2429         }
2430         strbuf_release(&freq->tmpfile);
2431 }