git.oblomov.eu Git - git/blob - 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 *curl_http_version = NULL;
  52 static const char *ssl_cert;
  53 static const char *ssl_cipherlist;
  54 static const char *ssl_version;
  55 static struct {
  56         const char *name;
  57         long ssl_version;
  58 } sslversions[] = {
  59         { "sslv2", CURL_SSLVERSION_SSLv2 },
  60         { "sslv3", CURL_SSLVERSION_SSLv3 },
  61         { "tlsv1", CURL_SSLVERSION_TLSv1 },
  62 #if LIBCURL_VERSION_NUM >= 0x072200
  63         { "tlsv1.0", CURL_SSLVERSION_TLSv1_0 },
  64         { "tlsv1.1", CURL_SSLVERSION_TLSv1_1 },
  65         { "tlsv1.2", CURL_SSLVERSION_TLSv1_2 },
  66 #endif
  67 #if LIBCURL_VERSION_NUM >= 0x073400
  68         { "tlsv1.3", CURL_SSLVERSION_TLSv1_3 },
  69 #endif
  70 };
  71 #if LIBCURL_VERSION_NUM >= 0x070903
  72 static const char *ssl_key;
  73 #endif
  74 #if LIBCURL_VERSION_NUM >= 0x070908
  75 static const char *ssl_capath;
  76 #endif
  77 #if LIBCURL_VERSION_NUM >= 0x071304
  78 static const char *curl_no_proxy;
  79 #endif
  80 #if LIBCURL_VERSION_NUM >= 0x072c00
  81 static const char *ssl_pinnedkey;
  82 #endif
  83 static const char *ssl_cainfo;
  84 static long curl_low_speed_limit = -1;
  85 static long curl_low_speed_time = -1;
  86 static int curl_ftp_no_epsv;
  87 static const char *curl_http_proxy;
  88 static const char *http_proxy_authmethod;
  89 static struct {
  90         const char *name;
  91         long curlauth_param;
  92 } proxy_authmethods[] = {
  93         { "basic", CURLAUTH_BASIC },
  94         { "digest", CURLAUTH_DIGEST },
  95         { "negotiate", CURLAUTH_GSSNEGOTIATE },
  96         { "ntlm", CURLAUTH_NTLM },
  97 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
  98         { "anyauth", CURLAUTH_ANY },
  99 #endif
 100         /*
 101          * CURLAUTH_DIGEST_IE has no corresponding command-line option in
 102          * curl(1) and is not included in CURLAUTH_ANY, so we leave it out
 103          * here, too
 104          */
 105 };
 106 #ifdef CURLGSSAPI_DELEGATION_FLAG
 107 static const char *curl_deleg;
 108 static struct {
 109         const char *name;
 110         long curl_deleg_param;
 111 } curl_deleg_levels[] = {
 112         { "none", CURLGSSAPI_DELEGATION_NONE },
 113         { "policy", CURLGSSAPI_DELEGATION_POLICY_FLAG },
 114         { "always", CURLGSSAPI_DELEGATION_FLAG },
 115 };
 116 #endif
 117
 118 static struct credential proxy_auth = CREDENTIAL_INIT;
 119 static const char *curl_proxyuserpwd;
 120 static const char *curl_cookie_file;
 121 static int curl_save_cookies;
 122 struct credential http_auth = CREDENTIAL_INIT;
 123 static int http_proactive_auth;
 124 static const char *user_agent;
 125 static int curl_empty_auth = -1;
 126
 127 enum http_follow_config http_follow_config = HTTP_FOLLOW_INITIAL;
 128
 129 #if LIBCURL_VERSION_NUM >= 0x071700
 130 /* Use CURLOPT_KEYPASSWD as is */
 131 #elif LIBCURL_VERSION_NUM >= 0x070903
 132 #define CURLOPT_KEYPASSWD CURLOPT_SSLKEYPASSWD
 133 #else
 134 #define CURLOPT_KEYPASSWD CURLOPT_SSLCERTPASSWD
 135 #endif
 136
 137 static struct credential cert_auth = CREDENTIAL_INIT;
 138 static int ssl_cert_password_required;
 139 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 140 static unsigned long http_auth_methods = CURLAUTH_ANY;
 141 static int http_auth_methods_restricted;
 142 /* Modes for which empty_auth cannot actually help us. */
 143 static unsigned long empty_auth_useless =
 144         CURLAUTH_BASIC
 145 #ifdef CURLAUTH_DIGEST_IE
 146         | CURLAUTH_DIGEST_IE
 147 #endif
 148         | CURLAUTH_DIGEST;
 149 #endif
 150
 151 static struct curl_slist *pragma_header;
 152 static struct curl_slist *no_pragma_header;
 153 static struct curl_slist *extra_http_headers;
 154
 155 static struct active_request_slot *active_queue_head;
 156
 157 static char *cached_accept_language;
 158
 159 static char *http_ssl_backend;
 160
 161 static int http_schannel_check_revoke = 1;
 162 /*
 163  * With the backend being set to `schannel`, setting sslCAinfo would override
 164  * the Certificate Store in cURL v7.60.0 and later, which is not what we want
 165  * by default.
 166  */
 167 static int http_schannel_use_ssl_cainfo;
 168
 169 size_t fread_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 170 {
 171         size_t size = eltsize * nmemb;
 172         struct buffer *buffer = buffer_;
 173
 174         if (size > buffer->buf.len - buffer->posn)
 175                 size = buffer->buf.len - buffer->posn;
 176         memcpy(ptr, buffer->buf.buf + buffer->posn, size);
 177         buffer->posn += size;
 178
 179         return size;
 180 }
 181
 182 #ifndef NO_CURL_IOCTL
 183 curlioerr ioctl_buffer(CURL *handle, int cmd, void *clientp)
 184 {
 185         struct buffer *buffer = clientp;
 186
 187         switch (cmd) {
 188         case CURLIOCMD_NOP:
 189                 return CURLIOE_OK;
 190
 191         case CURLIOCMD_RESTARTREAD:
 192                 buffer->posn = 0;
 193                 return CURLIOE_OK;
 194
 195         default:
 196                 return CURLIOE_UNKNOWNCMD;
 197         }
 198 }
 199 #endif
 200
 201 size_t fwrite_buffer(char *ptr, size_t eltsize, size_t nmemb, void *buffer_)
 202 {
 203         size_t size = eltsize * nmemb;
 204         struct strbuf *buffer = buffer_;
 205
 206         strbuf_add(buffer, ptr, size);
 207         return size;
 208 }
 209
 210 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 211 {
 212         return eltsize * nmemb;
 213 }
 214
 215 static void closedown_active_slot(struct active_request_slot *slot)
 216 {
 217         active_requests--;
 218         slot->in_use = 0;
 219 }
 220
 221 static void finish_active_slot(struct active_request_slot *slot)
 222 {
 223         closedown_active_slot(slot);
 224         curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE, &slot->http_code);
 225
 226         if (slot->finished != NULL)
 227                 (*slot->finished) = 1;
 228
 229         /* Store slot results so they can be read after the slot is reused */
 230         if (slot->results != NULL) {
 231                 slot->results->curl_result = slot->curl_result;
 232                 slot->results->http_code = slot->http_code;
 233 #if LIBCURL_VERSION_NUM >= 0x070a08
 234                 curl_easy_getinfo(slot->curl, CURLINFO_HTTPAUTH_AVAIL,
 235                                   &slot->results->auth_avail);
 236 #else
 237                 slot->results->auth_avail = 0;
 238 #endif
 239
 240                 curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CONNECTCODE,
 241                         &slot->results->http_connectcode);
 242         }
 243
 244         /* Run callback if appropriate */
 245         if (slot->callback_func != NULL)
 246                 slot->callback_func(slot->callback_data);
 247 }
 248
 249 static void xmulti_remove_handle(struct active_request_slot *slot)
 250 {
 251 #ifdef USE_CURL_MULTI
 252         curl_multi_remove_handle(curlm, slot->curl);
 253 #endif
 254 }
 255
 256 #ifdef USE_CURL_MULTI
 257 static void process_curl_messages(void)
 258 {
 259         int num_messages;
 260         struct active_request_slot *slot;
 261         CURLMsg *curl_message = curl_multi_info_read(curlm, &num_messages);
 262
 263         while (curl_message != NULL) {
 264                 if (curl_message->msg == CURLMSG_DONE) {
 265                         int curl_result = curl_message->data.result;
 266                         slot = active_queue_head;
 267                         while (slot != NULL &&
 268                                slot->curl != curl_message->easy_handle)
 269                                 slot = slot->next;
 270                         if (slot != NULL) {
 271                                 xmulti_remove_handle(slot);
 272                                 slot->curl_result = curl_result;
 273                                 finish_active_slot(slot);
 274                         } else {
 275                                 fprintf(stderr, "Received DONE message for unknown request!\n");
 276                         }
 277                 } else {
 278                         fprintf(stderr, "Unknown CURL message received: %d\n",
 279                                 (int)curl_message->msg);
 280                 }
 281                 curl_message = curl_multi_info_read(curlm, &num_messages);
 282         }
 283 }
 284 #endif
 285
 286 static int http_options(const char *var, const char *value, void *cb)
 287 {
 288         if (!strcmp("http.version", var)) {
 289                 return git_config_string(&curl_http_version, var, value);
 290         }
 291         if (!strcmp("http.sslverify", var)) {
 292                 curl_ssl_verify = git_config_bool(var, value);
 293                 return 0;
 294         }
 295         if (!strcmp("http.sslcipherlist", var))
 296                 return git_config_string(&ssl_cipherlist, var, value);
 297         if (!strcmp("http.sslversion", var))
 298                 return git_config_string(&ssl_version, var, value);
 299         if (!strcmp("http.sslcert", var))
 300                 return git_config_pathname(&ssl_cert, var, value);
 301 #if LIBCURL_VERSION_NUM >= 0x070903
 302         if (!strcmp("http.sslkey", var))
 303                 return git_config_pathname(&ssl_key, var, value);
 304 #endif
 305 #if LIBCURL_VERSION_NUM >= 0x070908
 306         if (!strcmp("http.sslcapath", var))
 307                 return git_config_pathname(&ssl_capath, var, value);
 308 #endif
 309         if (!strcmp("http.sslcainfo", var))
 310                 return git_config_pathname(&ssl_cainfo, var, value);
 311         if (!strcmp("http.sslcertpasswordprotected", var)) {
 312                 ssl_cert_password_required = git_config_bool(var, value);
 313                 return 0;
 314         }
 315         if (!strcmp("http.ssltry", var)) {
 316                 curl_ssl_try = git_config_bool(var, value);
 317                 return 0;
 318         }
 319         if (!strcmp("http.sslbackend", var)) {
 320                 free(http_ssl_backend);
 321                 http_ssl_backend = xstrdup_or_null(value);
 322                 return 0;
 323         }
 324
 325         if (!strcmp("http.schannelcheckrevoke", var)) {
 326                 http_schannel_check_revoke = git_config_bool(var, value);
 327                 return 0;
 328         }
 329
 330         if (!strcmp("http.schannelusesslcainfo", var)) {
 331                 http_schannel_use_ssl_cainfo = git_config_bool(var, value);
 332                 return 0;
 333         }
 334
 335         if (!strcmp("http.minsessions", var)) {
 336                 min_curl_sessions = git_config_int(var, value);
 337 #ifndef USE_CURL_MULTI
 338                 if (min_curl_sessions > 1)
 339                         min_curl_sessions = 1;
 340 #endif
 341                 return 0;
 342         }
 343 #ifdef USE_CURL_MULTI
 344         if (!strcmp("http.maxrequests", var)) {
 345                 max_requests = git_config_int(var, value);
 346                 return 0;
 347         }
 348 #endif
 349         if (!strcmp("http.lowspeedlimit", var)) {
 350                 curl_low_speed_limit = (long)git_config_int(var, value);
 351                 return 0;
 352         }
 353         if (!strcmp("http.lowspeedtime", var)) {
 354                 curl_low_speed_time = (long)git_config_int(var, value);
 355                 return 0;
 356         }
 357
 358         if (!strcmp("http.noepsv", var)) {
 359                 curl_ftp_no_epsv = git_config_bool(var, value);
 360                 return 0;
 361         }
 362         if (!strcmp("http.proxy", var))
 363                 return git_config_string(&curl_http_proxy, var, value);
 364
 365         if (!strcmp("http.proxyauthmethod", var))
 366                 return git_config_string(&http_proxy_authmethod, var, value);
 367
 368         if (!strcmp("http.cookiefile", var))
 369                 return git_config_pathname(&curl_cookie_file, var, value);
 370         if (!strcmp("http.savecookies", var)) {
 371                 curl_save_cookies = git_config_bool(var, value);
 372                 return 0;
 373         }
 374
 375         if (!strcmp("http.postbuffer", var)) {
 376                 http_post_buffer = git_config_ssize_t(var, value);
 377                 if (http_post_buffer < 0)
 378                         warning(_("negative value for http.postbuffer; defaulting to %d"), LARGE_PACKET_MAX);
 379                 if (http_post_buffer < LARGE_PACKET_MAX)
 380                         http_post_buffer = LARGE_PACKET_MAX;
 381                 return 0;
 382         }
 383
 384         if (!strcmp("http.useragent", var))
 385                 return git_config_string(&user_agent, var, value);
 386
 387         if (!strcmp("http.emptyauth", var)) {
 388                 if (value && !strcmp("auto", value))
 389                         curl_empty_auth = -1;
 390                 else
 391                         curl_empty_auth = git_config_bool(var, value);
 392                 return 0;
 393         }
 394
 395         if (!strcmp("http.delegation", var)) {
 396 #ifdef CURLGSSAPI_DELEGATION_FLAG
 397                 return git_config_string(&curl_deleg, var, value);
 398 #else
 399                 warning(_("Delegation control is not supported with cURL < 7.22.0"));
 400                 return 0;
 401 #endif
 402         }
 403
 404         if (!strcmp("http.pinnedpubkey", var)) {
 405 #if LIBCURL_VERSION_NUM >= 0x072c00
 406                 return git_config_pathname(&ssl_pinnedkey, var, value);
 407 #else
 408                 warning(_("Public key pinning not supported with cURL < 7.44.0"));
 409                 return 0;
 410 #endif
 411         }
 412
 413         if (!strcmp("http.extraheader", var)) {
 414                 if (!value) {
 415                         return config_error_nonbool(var);
 416                 } else if (!*value) {
 417                         curl_slist_free_all(extra_http_headers);
 418                         extra_http_headers = NULL;
 419                 } else {
 420                         extra_http_headers =
 421                                 curl_slist_append(extra_http_headers, value);
 422                 }
 423                 return 0;
 424         }
 425
 426         if (!strcmp("http.followredirects", var)) {
 427                 if (value && !strcmp(value, "initial"))
 428                         http_follow_config = HTTP_FOLLOW_INITIAL;
 429                 else if (git_config_bool(var, value))
 430                         http_follow_config = HTTP_FOLLOW_ALWAYS;
 431                 else
 432                         http_follow_config = HTTP_FOLLOW_NONE;
 433                 return 0;
 434         }
 435
 436         /* Fall back on the default ones */
 437         return git_default_config(var, value, cb);
 438 }
 439
 440 static int curl_empty_auth_enabled(void)
 441 {
 442         if (curl_empty_auth >= 0)
 443                 return curl_empty_auth;
 444
 445 #ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
 446         /*
 447          * Our libcurl is too old to do AUTH_ANY in the first place;
 448          * just default to turning the feature off.
 449          */
 450 #else
 451         /*
 452          * In the automatic case, kick in the empty-auth
 453          * hack as long as we would potentially try some
 454          * method more exotic than "Basic" or "Digest".
 455          *
 456          * But only do this when this is our second or
 457          * subsequent request, as by then we know what
 458          * methods are available.
 459          */
 460         if (http_auth_methods_restricted &&
 461             (http_auth_methods & ~empty_auth_useless))
 462                 return 1;
 463 #endif
 464         return 0;
 465 }
 466
 467 static void init_curl_http_auth(CURL *result)
 468 {
 469         if (!http_auth.username || !*http_auth.username) {
 470                 if (curl_empty_auth_enabled())
 471                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
 472                 return;
 473         }
 474
 475         credential_fill(&http_auth);
 476
 477 #if LIBCURL_VERSION_NUM >= 0x071301
 478         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 479         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 480 #else
 481         {
 482                 static struct strbuf up = STRBUF_INIT;
 483                 /*
 484                  * Note that we assume we only ever have a single set of
 485                  * credentials in a given program run, so we do not have
 486                  * to worry about updating this buffer, only setting its
 487                  * initial value.
 488                  */
 489                 if (!up.len)
 490                         strbuf_addf(&up, "%s:%s",
 491                                 http_auth.username, http_auth.password);
 492                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 493         }
 494 #endif
 495 }
 496
 497 /* *var must be free-able */
 498 static void var_override(const char **var, char *value)
 499 {
 500         if (value) {
 501                 free((void *)*var);
 502                 *var = xstrdup(value);
 503         }
 504 }
 505
 506 static void set_proxyauth_name_password(CURL *result)
 507 {
 508 #if LIBCURL_VERSION_NUM >= 0x071301
 509                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
 510                         proxy_auth.username);
 511                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
 512                         proxy_auth.password);
 513 #else
 514                 struct strbuf s = STRBUF_INIT;
 515
 516                 strbuf_addstr_urlencode(&s, proxy_auth.username, 1);
 517                 strbuf_addch(&s, ':');
 518                 strbuf_addstr_urlencode(&s, proxy_auth.password, 1);
 519                 curl_proxyuserpwd = strbuf_detach(&s, NULL);
 520                 curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
 521 #endif
 522 }
 523
 524 static void init_curl_proxy_auth(CURL *result)
 525 {
 526         if (proxy_auth.username) {
 527                 if (!proxy_auth.password)
 528                         credential_fill(&proxy_auth);
 529                 set_proxyauth_name_password(result);
 530         }
 531
 532         var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
 533
 534 #if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
 535         if (http_proxy_authmethod) {
 536                 int i;
 537                 for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
 538                         if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
 539                                 curl_easy_setopt(result, CURLOPT_PROXYAUTH,
 540                                                 proxy_authmethods[i].curlauth_param);
 541                                 break;
 542                         }
 543                 }
 544                 if (i == ARRAY_SIZE(proxy_authmethods)) {
 545                         warning("unsupported proxy authentication method %s: using anyauth",
 546                                         http_proxy_authmethod);
 547                         curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 548                 }
 549         }
 550         else
 551                 curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 552 #endif
 553 }
 554
 555 static int has_cert_password(void)
 556 {
 557         if (ssl_cert == NULL || ssl_cert_password_required != 1)
 558                 return 0;
 559         if (!cert_auth.password) {
 560                 cert_auth.protocol = xstrdup("cert");
 561                 cert_auth.username = xstrdup("");
 562                 cert_auth.path = xstrdup(ssl_cert);
 563                 credential_fill(&cert_auth);
 564         }
 565         return 1;
 566 }
 567
 568 #if LIBCURL_VERSION_NUM >= 0x071900
 569 static void set_curl_keepalive(CURL *c)
 570 {
 571         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 572 }
 573
 574 #elif LIBCURL_VERSION_NUM >= 0x071000
 575 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 576 {
 577         int ka = 1;
 578         int rc;
 579         socklen_t len = (socklen_t)sizeof(ka);
 580
 581         if (type != CURLSOCKTYPE_IPCXN)
 582                 return 0;
 583
 584         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 585         if (rc < 0)
 586                 warning_errno("unable to set SO_KEEPALIVE on socket");
 587
 588         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 589 }
 590
 591 static void set_curl_keepalive(CURL *c)
 592 {
 593         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 594 }
 595
 596 #else
 597 static void set_curl_keepalive(CURL *c)
 598 {
 599         /* not supported on older curl versions */
 600 }
 601 #endif
 602
 603 static void redact_sensitive_header(struct strbuf *header)
 604 {
 605         const char *sensitive_header;
 606
 607         if (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
 608             skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header)) {
 609                 /* The first token is the type, which is OK to log */
 610                 while (isspace(*sensitive_header))
 611                         sensitive_header++;
 612                 while (*sensitive_header && !isspace(*sensitive_header))
 613                         sensitive_header++;
 614                 /* Everything else is opaque and possibly sensitive */
 615                 strbuf_setlen(header,  sensitive_header - header->buf);
 616                 strbuf_addstr(header, " <redacted>");
 617         } else if (cookies_to_redact.nr &&
 618                    skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
 619                 struct strbuf redacted_header = STRBUF_INIT;
 620                 char *cookie;
 621
 622                 while (isspace(*sensitive_header))
 623                         sensitive_header++;
 624
 625                 /*
 626                  * The contents of header starting from sensitive_header will
 627                  * subsequently be overridden, so it is fine to mutate this
 628                  * string (hence the assignment to "char *").
 629                  */
 630                 cookie = (char *) sensitive_header;
 631
 632                 while (cookie) {
 633                         char *equals;
 634                         char *semicolon = strstr(cookie, "; ");
 635                         if (semicolon)
 636                                 *semicolon = 0;
 637                         equals = strchrnul(cookie, '=');
 638                         if (!equals) {
 639                                 /* invalid cookie, just append and continue */
 640                                 strbuf_addstr(&redacted_header, cookie);
 641                                 continue;
 642                         }
 643                         *equals = 0; /* temporarily set to NUL for lookup */
 644                         if (string_list_lookup(&cookies_to_redact, cookie)) {
 645                                 strbuf_addstr(&redacted_header, cookie);
 646                                 strbuf_addstr(&redacted_header, "=<redacted>");
 647                         } else {
 648                                 *equals = '=';
 649                                 strbuf_addstr(&redacted_header, cookie);
 650                         }
 651                         if (semicolon) {
 652                                 /*
 653                                  * There are more cookies. (Or, for some
 654                                  * reason, the input string ends in "; ".)
 655                                  */
 656                                 strbuf_addstr(&redacted_header, "; ");
 657                                 cookie = semicolon + strlen("; ");
 658                         } else {
 659                                 cookie = NULL;
 660                         }
 661                 }
 662
 663                 strbuf_setlen(header, sensitive_header - header->buf);
 664                 strbuf_addbuf(header, &redacted_header);
 665         }
 666 }
 667
 668 static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
 669 {
 670         struct strbuf out = STRBUF_INIT;
 671         struct strbuf **headers, **header;
 672
 673         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 674                 text, (long)size, (long)size);
 675         trace_strbuf(&trace_curl, &out);
 676         strbuf_reset(&out);
 677         strbuf_add(&out, ptr, size);
 678         headers = strbuf_split_max(&out, '\n', 0);
 679
 680         for (header = headers; *header; header++) {
 681                 if (hide_sensitive_header)
 682                         redact_sensitive_header(*header);
 683                 strbuf_insert((*header), 0, text, strlen(text));
 684                 strbuf_insert((*header), strlen(text), ": ", 2);
 685                 strbuf_rtrim((*header));
 686                 strbuf_addch((*header), '\n');
 687                 trace_strbuf(&trace_curl, (*header));
 688         }
 689         strbuf_list_free(headers);
 690         strbuf_release(&out);
 691 }
 692
 693 static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
 694 {
 695         size_t i;
 696         struct strbuf out = STRBUF_INIT;
 697         unsigned int width = 60;
 698
 699         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 700                 text, (long)size, (long)size);
 701         trace_strbuf(&trace_curl, &out);
 702
 703         for (i = 0; i < size; i += width) {
 704                 size_t w;
 705
 706                 strbuf_reset(&out);
 707                 strbuf_addf(&out, "%s: ", text);
 708                 for (w = 0; (w < width) && (i + w < size); w++) {
 709                         unsigned char ch = ptr[i + w];
 710
 711                         strbuf_addch(&out,
 712                                        (ch >= 0x20) && (ch < 0x80)
 713                                        ? ch : '.');
 714                 }
 715                 strbuf_addch(&out, '\n');
 716                 trace_strbuf(&trace_curl, &out);
 717         }
 718         strbuf_release(&out);
 719 }
 720
 721 static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
 722 {
 723         const char *text;
 724         enum { NO_FILTER = 0, DO_FILTER = 1 };
 725
 726         switch (type) {
 727         case CURLINFO_TEXT:
 728                 trace_printf_key(&trace_curl, "== Info: %s", data);
 729                 break;
 730         case CURLINFO_HEADER_OUT:
 731                 text = "=> Send header";
 732                 curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
 733                 break;
 734         case CURLINFO_DATA_OUT:
 735                 if (trace_curl_data) {
 736                         text = "=> Send data";
 737                         curl_dump_data(text, (unsigned char *)data, size);
 738                 }
 739                 break;
 740         case CURLINFO_SSL_DATA_OUT:
 741                 if (trace_curl_data) {
 742                         text = "=> Send SSL data";
 743                         curl_dump_data(text, (unsigned char *)data, size);
 744                 }
 745                 break;
 746         case CURLINFO_HEADER_IN:
 747                 text = "<= Recv header";
 748                 curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
 749                 break;
 750         case CURLINFO_DATA_IN:
 751                 if (trace_curl_data) {
 752                         text = "<= Recv data";
 753                         curl_dump_data(text, (unsigned char *)data, size);
 754                 }
 755                 break;
 756         case CURLINFO_SSL_DATA_IN:
 757                 if (trace_curl_data) {
 758                         text = "<= Recv SSL data";
 759                         curl_dump_data(text, (unsigned char *)data, size);
 760                 }
 761                 break;
 762
 763         default:                /* we ignore unknown types by default */
 764                 return 0;
 765         }
 766         return 0;
 767 }
 768
 769 void setup_curl_trace(CURL *handle)
 770 {
 771         if (!trace_want(&trace_curl))
 772                 return;
 773         curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
 774         curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
 775         curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
 776 }
 777
 778 #ifdef CURLPROTO_HTTP
 779 static long get_curl_allowed_protocols(int from_user)
 780 {
 781         long allowed_protocols = 0;
 782
 783         if (is_transport_allowed("http", from_user))
 784                 allowed_protocols |= CURLPROTO_HTTP;
 785         if (is_transport_allowed("https", from_user))
 786                 allowed_protocols |= CURLPROTO_HTTPS;
 787         if (is_transport_allowed("ftp", from_user))
 788                 allowed_protocols |= CURLPROTO_FTP;
 789         if (is_transport_allowed("ftps", from_user))
 790                 allowed_protocols |= CURLPROTO_FTPS;
 791
 792         return allowed_protocols;
 793 }
 794 #endif
 795
 796 #if LIBCURL_VERSION_NUM >=0x072f00
 797 static int get_curl_http_version_opt(const char *version_string, long *opt)
 798 {
 799         int i;
 800         static struct {
 801                 const char *name;
 802                 long opt_token;
 803         } choice[] = {
 804                 { "HTTP/1.1", CURL_HTTP_VERSION_1_1 },
 805                 { "HTTP/2", CURL_HTTP_VERSION_2 }
 806         };
 807
 808         for (i = 0; i < ARRAY_SIZE(choice); i++) {
 809                 if (!strcmp(version_string, choice[i].name)) {
 810                         *opt = choice[i].opt_token;
 811                         return 0;
 812                 }
 813         }
 814
 815         warning("unknown value given to http.version: '%s'", version_string);
 816         return -1; /* not found */
 817 }
 818
 819 #endif
 820
 821 static CURL *get_curl_handle(void)
 822 {
 823         CURL *result = curl_easy_init();
 824
 825         if (!result)
 826                 die("curl_easy_init failed");
 827
 828         if (!curl_ssl_verify) {
 829                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 830                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 831         } else {
 832                 /* Verify authenticity of the peer's certificate */
 833                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 834                 /* The name in the cert must match whom we tried to connect */
 835                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 836         }
 837
 838 #if LIBCURL_VERSION_NUM >= 0x072f00 // 7.47.0
 839     if (curl_http_version) {
 840                 long opt;
 841                 if (!get_curl_http_version_opt(curl_http_version, &opt)) {
 842                         /* Set request use http version */
 843                         curl_easy_setopt(result, CURLOPT_HTTP_VERSION, opt);
 844                 }
 845     }
 846 #endif
 847
 848 #if LIBCURL_VERSION_NUM >= 0x070907
 849         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 850 #endif
 851 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 852         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 853 #endif
 854
 855 #ifdef CURLGSSAPI_DELEGATION_FLAG
 856         if (curl_deleg) {
 857                 int i;
 858                 for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
 859                         if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
 860                                 curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
 861                                                 curl_deleg_levels[i].curl_deleg_param);
 862                                 break;
 863                         }
 864                 }
 865                 if (i == ARRAY_SIZE(curl_deleg_levels))
 866                         warning("Unknown delegation method '%s': using default",
 867                                 curl_deleg);
 868         }
 869 #endif
 870
 871         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 872             !http_schannel_check_revoke) {
 873 #if LIBCURL_VERSION_NUM >= 0x072c00
 874                 curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
 875 #else
 876                 warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
 877 #endif
 878         }
 879
 880         if (http_proactive_auth)
 881                 init_curl_http_auth(result);
 882
 883         if (getenv("GIT_SSL_VERSION"))
 884                 ssl_version = getenv("GIT_SSL_VERSION");
 885         if (ssl_version && *ssl_version) {
 886                 int i;
 887                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 888                         if (!strcmp(ssl_version, sslversions[i].name)) {
 889                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 890                                                  sslversions[i].ssl_version);
 891                                 break;
 892                         }
 893                 }
 894                 if (i == ARRAY_SIZE(sslversions))
 895                         warning("unsupported ssl version %s: using default",
 896                                 ssl_version);
 897         }
 898
 899         if (getenv("GIT_SSL_CIPHER_LIST"))
 900                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 901         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 902                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 903                                 ssl_cipherlist);
 904
 905         if (ssl_cert != NULL)
 906                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 907         if (has_cert_password())
 908                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 909 #if LIBCURL_VERSION_NUM >= 0x070903
 910         if (ssl_key != NULL)
 911                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 912 #endif
 913 #if LIBCURL_VERSION_NUM >= 0x070908
 914         if (ssl_capath != NULL)
 915                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 916 #endif
 917 #if LIBCURL_VERSION_NUM >= 0x072c00
 918         if (ssl_pinnedkey != NULL)
 919                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 920 #endif
 921         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 922             !http_schannel_use_ssl_cainfo) {
 923                 curl_easy_setopt(result, CURLOPT_CAINFO, NULL);
 924 #if LIBCURL_VERSION_NUM >= 0x073400
 925                 curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, NULL);
 926 #endif
 927         } else if (ssl_cainfo != NULL)
 928                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 929
 930         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 931                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 932                                  curl_low_speed_limit);
 933                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 934                                  curl_low_speed_time);
 935         }
 936
 937         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 938 #if LIBCURL_VERSION_NUM >= 0x071301
 939         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 940 #elif LIBCURL_VERSION_NUM >= 0x071101
 941         curl_easy_setopt(result, CURLOPT_POST301, 1);
 942 #endif
 943 #ifdef CURLPROTO_HTTP
 944         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
 945                          get_curl_allowed_protocols(0));
 946         curl_easy_setopt(result, CURLOPT_PROTOCOLS,
 947                          get_curl_allowed_protocols(-1));
 948 #else
 949         warning(_("Protocol restrictions not supported with cURL < 7.19.4"));
 950 #endif
 951         if (getenv("GIT_CURL_VERBOSE"))
 952                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1L);
 953         setup_curl_trace(result);
 954         if (getenv("GIT_TRACE_CURL_NO_DATA"))
 955                 trace_curl_data = 0;
 956         if (getenv("GIT_REDACT_COOKIES")) {
 957                 string_list_split(&cookies_to_redact,
 958                                   getenv("GIT_REDACT_COOKIES"), ',', -1);
 959                 string_list_sort(&cookies_to_redact);
 960         }
 961
 962         curl_easy_setopt(result, CURLOPT_USERAGENT,
 963                 user_agent ? user_agent : git_user_agent());
 964
 965         if (curl_ftp_no_epsv)
 966                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 967
 968 #ifdef CURLOPT_USE_SSL
 969         if (curl_ssl_try)
 970                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 971 #endif
 972
 973         /*
 974          * CURL also examines these variables as a fallback; but we need to query
 975          * them here in order to decide whether to prompt for missing password (cf.
 976          * init_curl_proxy_auth()).
 977          *
 978          * Unlike many other common environment variables, these are historically
 979          * lowercase only. It appears that CURL did not know this and implemented
 980          * only uppercase variants, which was later corrected to take both - with
 981          * the exception of http_proxy, which is lowercase only also in CURL. As
 982          * the lowercase versions are the historical quasi-standard, they take
 983          * precedence here, as in CURL.
 984          */
 985         if (!curl_http_proxy) {
 986                 if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
 987                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
 988                         var_override(&curl_http_proxy, getenv("https_proxy"));
 989                 } else {
 990                         var_override(&curl_http_proxy, getenv("http_proxy"));
 991                 }
 992                 if (!curl_http_proxy) {
 993                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
 994                         var_override(&curl_http_proxy, getenv("all_proxy"));
 995                 }
 996         }
 997
 998         if (curl_http_proxy && curl_http_proxy[0] == '\0') {
 999                 /*
1000                  * Handle case with the empty http.proxy value here to keep
1001                  * common code clean.
1002                  * NB: empty option disables proxying at all.
1003                  */
1004                 curl_easy_setopt(result, CURLOPT_PROXY, "");
1005         } else if (curl_http_proxy) {
1006 #if LIBCURL_VERSION_NUM >= 0x071800
1007                 if (starts_with(curl_http_proxy, "socks5h"))
1008                         curl_easy_setopt(result,
1009                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
1010                 else if (starts_with(curl_http_proxy, "socks5"))
1011                         curl_easy_setopt(result,
1012                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
1013                 else if (starts_with(curl_http_proxy, "socks4a"))
1014                         curl_easy_setopt(result,
1015                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
1016                 else if (starts_with(curl_http_proxy, "socks"))
1017                         curl_easy_setopt(result,
1018                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
1019 #endif
1020 #if LIBCURL_VERSION_NUM >= 0x073400
1021                 else if (starts_with(curl_http_proxy, "https"))
1022                         curl_easy_setopt(result,
1023                                 CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
1024 #endif
1025                 if (strstr(curl_http_proxy, "://"))
1026                         credential_from_url(&proxy_auth, curl_http_proxy);
1027                 else {
1028                         struct strbuf url = STRBUF_INIT;
1029                         strbuf_addf(&url, "http://%s", curl_http_proxy);
1030                         credential_from_url(&proxy_auth, url.buf);
1031                         strbuf_release(&url);
1032                 }
1033
1034                 if (!proxy_auth.host)
1035                         die("Invalid proxy URL '%s'", curl_http_proxy);
1036
1037                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
1038 #if LIBCURL_VERSION_NUM >= 0x071304
1039                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
1040                 var_override(&curl_no_proxy, getenv("no_proxy"));
1041                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
1042 #endif
1043         }
1044         init_curl_proxy_auth(result);
1045
1046         set_curl_keepalive(result);
1047
1048         return result;
1049 }
1050
1051 static void set_from_env(const char **var, const char *envname)
1052 {
1053         const char *val = getenv(envname);
1054         if (val)
1055                 *var = val;
1056 }
1057
1058 void http_init(struct remote *remote, const char *url, int proactive_auth)
1059 {
1060         char *low_speed_limit;
1061         char *low_speed_time;
1062         char *normalized_url;
1063         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
1064
1065         config.section = "http";
1066         config.key = NULL;
1067         config.collect_fn = http_options;
1068         config.cascade_fn = git_default_config;
1069         config.cb = NULL;
1070
1071         http_is_verbose = 0;
1072         normalized_url = url_normalize(url, &config.url);
1073
1074         git_config(urlmatch_config_entry, &config);
1075         free(normalized_url);
1076
1077 #if LIBCURL_VERSION_NUM >= 0x073800
1078         if (http_ssl_backend) {
1079                 const curl_ssl_backend **backends;
1080                 struct strbuf buf = STRBUF_INIT;
1081                 int i;
1082
1083                 switch (curl_global_sslset(-1, http_ssl_backend, &backends)) {
1084                 case CURLSSLSET_UNKNOWN_BACKEND:
1085                         strbuf_addf(&buf, _("Unsupported SSL backend '%s'. "
1086                                             "Supported SSL backends:"),
1087                                             http_ssl_backend);
1088                         for (i = 0; backends[i]; i++)
1089                                 strbuf_addf(&buf, "\n\t%s", backends[i]->name);
1090                         die("%s", buf.buf);
1091                 case CURLSSLSET_NO_BACKENDS:
1092                         die(_("Could not set SSL backend to '%s': "
1093                               "cURL was built without SSL backends"),
1094                             http_ssl_backend);
1095                 case CURLSSLSET_TOO_LATE:
1096                         die(_("Could not set SSL backend to '%s': already set"),
1097                             http_ssl_backend);
1098                 case CURLSSLSET_OK:
1099                         break; /* Okay! */
1100                 }
1101         }
1102 #endif
1103
1104         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
1105                 die("curl_global_init failed");
1106
1107         http_proactive_auth = proactive_auth;
1108
1109         if (remote && remote->http_proxy)
1110                 curl_http_proxy = xstrdup(remote->http_proxy);
1111
1112         if (remote)
1113                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
1114
1115         pragma_header = curl_slist_append(http_copy_default_headers(),
1116                 "Pragma: no-cache");
1117         no_pragma_header = curl_slist_append(http_copy_default_headers(),
1118                 "Pragma:");
1119
1120 #ifdef USE_CURL_MULTI
1121         {
1122                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
1123                 if (http_max_requests != NULL)
1124                         max_requests = atoi(http_max_requests);
1125         }
1126
1127         curlm = curl_multi_init();
1128         if (!curlm)
1129                 die("curl_multi_init failed");
1130 #endif
1131
1132         if (getenv("GIT_SSL_NO_VERIFY"))
1133                 curl_ssl_verify = 0;
1134
1135         set_from_env(&ssl_cert, "GIT_SSL_CERT");
1136 #if LIBCURL_VERSION_NUM >= 0x070903
1137         set_from_env(&ssl_key, "GIT_SSL_KEY");
1138 #endif
1139 #if LIBCURL_VERSION_NUM >= 0x070908
1140         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
1141 #endif
1142         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
1143
1144         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
1145
1146         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
1147         if (low_speed_limit != NULL)
1148                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
1149         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
1150         if (low_speed_time != NULL)
1151                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
1152
1153         if (curl_ssl_verify == -1)
1154                 curl_ssl_verify = 1;
1155
1156         curl_session_count = 0;
1157 #ifdef USE_CURL_MULTI
1158         if (max_requests < 1)
1159                 max_requests = DEFAULT_MAX_REQUESTS;
1160 #endif
1161
1162         if (getenv("GIT_CURL_FTP_NO_EPSV"))
1163                 curl_ftp_no_epsv = 1;
1164
1165         if (url) {
1166                 credential_from_url(&http_auth, url);
1167                 if (!ssl_cert_password_required &&
1168                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
1169                     starts_with(url, "https://"))
1170                         ssl_cert_password_required = 1;
1171         }
1172
1173 #ifndef NO_CURL_EASY_DUPHANDLE
1174         curl_default = get_curl_handle();
1175 #endif
1176 }
1177
1178 void http_cleanup(void)
1179 {
1180         struct active_request_slot *slot = active_queue_head;
1181
1182         while (slot != NULL) {
1183                 struct active_request_slot *next = slot->next;
1184                 if (slot->curl != NULL) {
1185                         xmulti_remove_handle(slot);
1186                         curl_easy_cleanup(slot->curl);
1187                 }
1188                 free(slot);
1189                 slot = next;
1190         }
1191         active_queue_head = NULL;
1192
1193 #ifndef NO_CURL_EASY_DUPHANDLE
1194         curl_easy_cleanup(curl_default);
1195 #endif
1196
1197 #ifdef USE_CURL_MULTI
1198         curl_multi_cleanup(curlm);
1199 #endif
1200         curl_global_cleanup();
1201
1202         curl_slist_free_all(extra_http_headers);
1203         extra_http_headers = NULL;
1204
1205         curl_slist_free_all(pragma_header);
1206         pragma_header = NULL;
1207
1208         curl_slist_free_all(no_pragma_header);
1209         no_pragma_header = NULL;
1210
1211         if (curl_http_proxy) {
1212                 free((void *)curl_http_proxy);
1213                 curl_http_proxy = NULL;
1214         }
1215
1216         if (proxy_auth.password) {
1217                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1218                 FREE_AND_NULL(proxy_auth.password);
1219         }
1220
1221         free((void *)curl_proxyuserpwd);
1222         curl_proxyuserpwd = NULL;
1223
1224         free((void *)http_proxy_authmethod);
1225         http_proxy_authmethod = NULL;
1226
1227         if (cert_auth.password != NULL) {
1228                 memset(cert_auth.password, 0, strlen(cert_auth.password));
1229                 FREE_AND_NULL(cert_auth.password);
1230         }
1231         ssl_cert_password_required = 0;
1232
1233         FREE_AND_NULL(cached_accept_language);
1234 }
1235
1236 struct active_request_slot *get_active_slot(void)
1237 {
1238         struct active_request_slot *slot = active_queue_head;
1239         struct active_request_slot *newslot;
1240
1241 #ifdef USE_CURL_MULTI
1242         int num_transfers;
1243
1244         /* Wait for a slot to open up if the queue is full */
1245         while (active_requests >= max_requests) {
1246                 curl_multi_perform(curlm, &num_transfers);
1247                 if (num_transfers < active_requests)
1248                         process_curl_messages();
1249         }
1250 #endif
1251
1252         while (slot != NULL && slot->in_use)
1253                 slot = slot->next;
1254
1255         if (slot == NULL) {
1256                 newslot = xmalloc(sizeof(*newslot));
1257                 newslot->curl = NULL;
1258                 newslot->in_use = 0;
1259                 newslot->next = NULL;
1260
1261                 slot = active_queue_head;
1262                 if (slot == NULL) {
1263                         active_queue_head = newslot;
1264                 } else {
1265                         while (slot->next != NULL)
1266                                 slot = slot->next;
1267                         slot->next = newslot;
1268                 }
1269                 slot = newslot;
1270         }
1271
1272         if (slot->curl == NULL) {
1273 #ifdef NO_CURL_EASY_DUPHANDLE
1274                 slot->curl = get_curl_handle();
1275 #else
1276                 slot->curl = curl_easy_duphandle(curl_default);
1277 #endif
1278                 curl_session_count++;
1279         }
1280
1281         active_requests++;
1282         slot->in_use = 1;
1283         slot->results = NULL;
1284         slot->finished = NULL;
1285         slot->callback_data = NULL;
1286         slot->callback_func = NULL;
1287         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1288         if (curl_save_cookies)
1289                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1290         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1291         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1292         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1293         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1294         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1295         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1296         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1297         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1298         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1299         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1300
1301         /*
1302          * Default following to off unless "ALWAYS" is configured; this gives
1303          * callers a sane starting point, and they can tweak for individual
1304          * HTTP_FOLLOW_* cases themselves.
1305          */
1306         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1307                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1308         else
1309                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1310
1311 #if LIBCURL_VERSION_NUM >= 0x070a08
1312         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1313 #endif
1314 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1315         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1316 #endif
1317         if (http_auth.password || curl_empty_auth_enabled())
1318                 init_curl_http_auth(slot->curl);
1319
1320         return slot;
1321 }
1322
1323 int start_active_slot(struct active_request_slot *slot)
1324 {
1325 #ifdef USE_CURL_MULTI
1326         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1327         int num_transfers;
1328
1329         if (curlm_result != CURLM_OK &&
1330             curlm_result != CURLM_CALL_MULTI_PERFORM) {
1331                 warning("curl_multi_add_handle failed: %s",
1332                         curl_multi_strerror(curlm_result));
1333                 active_requests--;
1334                 slot->in_use = 0;
1335                 return 0;
1336         }
1337
1338         /*
1339          * We know there must be something to do, since we just added
1340          * something.
1341          */
1342         curl_multi_perform(curlm, &num_transfers);
1343 #endif
1344         return 1;
1345 }
1346
1347 #ifdef USE_CURL_MULTI
1348 struct fill_chain {
1349         void *data;
1350         int (*fill)(void *);
1351         struct fill_chain *next;
1352 };
1353
1354 static struct fill_chain *fill_cfg;
1355
1356 void add_fill_function(void *data, int (*fill)(void *))
1357 {
1358         struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
1359         struct fill_chain **linkp = &fill_cfg;
1360         new_fill->data = data;
1361         new_fill->fill = fill;
1362         new_fill->next = NULL;
1363         while (*linkp)
1364                 linkp = &(*linkp)->next;
1365         *linkp = new_fill;
1366 }
1367
1368 void fill_active_slots(void)
1369 {
1370         struct active_request_slot *slot = active_queue_head;
1371
1372         while (active_requests < max_requests) {
1373                 struct fill_chain *fill;
1374                 for (fill = fill_cfg; fill; fill = fill->next)
1375                         if (fill->fill(fill->data))
1376                                 break;
1377
1378                 if (!fill)
1379                         break;
1380         }
1381
1382         while (slot != NULL) {
1383                 if (!slot->in_use && slot->curl != NULL
1384                         && curl_session_count > min_curl_sessions) {
1385                         curl_easy_cleanup(slot->curl);
1386                         slot->curl = NULL;
1387                         curl_session_count--;
1388                 }
1389                 slot = slot->next;
1390         }
1391 }
1392
1393 void step_active_slots(void)
1394 {
1395         int num_transfers;
1396         CURLMcode curlm_result;
1397
1398         do {
1399                 curlm_result = curl_multi_perform(curlm, &num_transfers);
1400         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1401         if (num_transfers < active_requests) {
1402                 process_curl_messages();
1403                 fill_active_slots();
1404         }
1405 }
1406 #endif
1407
1408 void run_active_slot(struct active_request_slot *slot)
1409 {
1410 #ifdef USE_CURL_MULTI
1411         fd_set readfds;
1412         fd_set writefds;
1413         fd_set excfds;
1414         int max_fd;
1415         struct timeval select_timeout;
1416         int finished = 0;
1417
1418         slot->finished = &finished;
1419         while (!finished) {
1420                 step_active_slots();
1421
1422                 if (slot->in_use) {
1423 #if LIBCURL_VERSION_NUM >= 0x070f04
1424                         long curl_timeout;
1425                         curl_multi_timeout(curlm, &curl_timeout);
1426                         if (curl_timeout == 0) {
1427                                 continue;
1428                         } else if (curl_timeout == -1) {
1429                                 select_timeout.tv_sec  = 0;
1430                                 select_timeout.tv_usec = 50000;
1431                         } else {
1432                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1433                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1434                         }
1435 #else
1436                         select_timeout.tv_sec  = 0;
1437                         select_timeout.tv_usec = 50000;
1438 #endif
1439
1440                         max_fd = -1;
1441                         FD_ZERO(&readfds);
1442                         FD_ZERO(&writefds);
1443                         FD_ZERO(&excfds);
1444                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1445
1446                         /*
1447                          * It can happen that curl_multi_timeout returns a pathologically
1448                          * long timeout when curl_multi_fdset returns no file descriptors
1449                          * to read.  See commit message for more details.
1450                          */
1451                         if (max_fd < 0 &&
1452                             (select_timeout.tv_sec > 0 ||
1453                              select_timeout.tv_usec > 50000)) {
1454                                 select_timeout.tv_sec  = 0;
1455                                 select_timeout.tv_usec = 50000;
1456                         }
1457
1458                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1459                 }
1460         }
1461 #else
1462         while (slot->in_use) {
1463                 slot->curl_result = curl_easy_perform(slot->curl);
1464                 finish_active_slot(slot);
1465         }
1466 #endif
1467 }
1468
1469 static void release_active_slot(struct active_request_slot *slot)
1470 {
1471         closedown_active_slot(slot);
1472         if (slot->curl) {
1473                 xmulti_remove_handle(slot);
1474                 if (curl_session_count > min_curl_sessions) {
1475                         curl_easy_cleanup(slot->curl);
1476                         slot->curl = NULL;
1477                         curl_session_count--;
1478                 }
1479         }
1480 #ifdef USE_CURL_MULTI
1481         fill_active_slots();
1482 #endif
1483 }
1484
1485 void finish_all_active_slots(void)
1486 {
1487         struct active_request_slot *slot = active_queue_head;
1488
1489         while (slot != NULL)
1490                 if (slot->in_use) {
1491                         run_active_slot(slot);
1492                         slot = active_queue_head;
1493                 } else {
1494                         slot = slot->next;
1495                 }
1496 }
1497
1498 /* Helpers for modifying and creating URLs */
1499 static inline int needs_quote(int ch)
1500 {
1501         if (((ch >= 'A') && (ch <= 'Z'))
1502                         || ((ch >= 'a') && (ch <= 'z'))
1503                         || ((ch >= '0') && (ch <= '9'))
1504                         || (ch == '/')
1505                         || (ch == '-')
1506                         || (ch == '.'))
1507                 return 0;
1508         return 1;
1509 }
1510
1511 static char *quote_ref_url(const char *base, const char *ref)
1512 {
1513         struct strbuf buf = STRBUF_INIT;
1514         const char *cp;
1515         int ch;
1516
1517         end_url_with_slash(&buf, base);
1518
1519         for (cp = ref; (ch = *cp) != 0; cp++)
1520                 if (needs_quote(ch))
1521                         strbuf_addf(&buf, "%%%02x", ch);
1522                 else
1523                         strbuf_addch(&buf, *cp);
1524
1525         return strbuf_detach(&buf, NULL);
1526 }
1527
1528 void append_remote_object_url(struct strbuf *buf, const char *url,
1529                               const char *hex,
1530                               int only_two_digit_prefix)
1531 {
1532         end_url_with_slash(buf, url);
1533
1534         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1535         if (!only_two_digit_prefix)
1536                 strbuf_addstr(buf, hex + 2);
1537 }
1538
1539 char *get_remote_object_url(const char *url, const char *hex,
1540                             int only_two_digit_prefix)
1541 {
1542         struct strbuf buf = STRBUF_INIT;
1543         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1544         return strbuf_detach(&buf, NULL);
1545 }
1546
1547 static int handle_curl_result(struct slot_results *results)
1548 {
1549         /*
1550          * If we see a failing http code with CURLE_OK, we have turned off
1551          * FAILONERROR (to keep the server's custom error response), and should
1552          * translate the code into failure here.
1553          *
1554          * Likewise, if we see a redirect (30x code), that means we turned off
1555          * redirect-following, and we should treat the result as an error.
1556          */
1557         if (results->curl_result == CURLE_OK &&
1558             results->http_code >= 300) {
1559                 results->curl_result = CURLE_HTTP_RETURNED_ERROR;
1560                 /*
1561                  * Normally curl will already have put the "reason phrase"
1562                  * from the server into curl_errorstr; unfortunately without
1563                  * FAILONERROR it is lost, so we can give only the numeric
1564                  * status code.
1565                  */
1566                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1567                           "The requested URL returned error: %ld",
1568                           results->http_code);
1569         }
1570
1571         if (results->curl_result == CURLE_OK) {
1572                 credential_approve(&http_auth);
1573                 if (proxy_auth.password)
1574                         credential_approve(&proxy_auth);
1575                 return HTTP_OK;
1576         } else if (missing_target(results))
1577                 return HTTP_MISSING_TARGET;
1578         else if (results->http_code == 401) {
1579                 if (http_auth.username && http_auth.password) {
1580                         credential_reject(&http_auth);
1581                         return HTTP_NOAUTH;
1582                 } else {
1583 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1584                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1585                         if (results->auth_avail) {
1586                                 http_auth_methods &= results->auth_avail;
1587                                 http_auth_methods_restricted = 1;
1588                         }
1589 #endif
1590                         return HTTP_REAUTH;
1591                 }
1592         } else {
1593                 if (results->http_connectcode == 407)
1594                         credential_reject(&proxy_auth);
1595 #if LIBCURL_VERSION_NUM >= 0x070c00
1596                 if (!curl_errorstr[0])
1597                         strlcpy(curl_errorstr,
1598                                 curl_easy_strerror(results->curl_result),
1599                                 sizeof(curl_errorstr));
1600 #endif
1601                 return HTTP_ERROR;
1602         }
1603 }
1604
1605 int run_one_slot(struct active_request_slot *slot,
1606                  struct slot_results *results)
1607 {
1608         slot->results = results;
1609         if (!start_active_slot(slot)) {
1610                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1611                           "failed to start HTTP request");
1612                 return HTTP_START_FAILED;
1613         }
1614
1615         run_active_slot(slot);
1616         return handle_curl_result(results);
1617 }
1618
1619 struct curl_slist *http_copy_default_headers(void)
1620 {
1621         struct curl_slist *headers = NULL, *h;
1622
1623         for (h = extra_http_headers; h; h = h->next)
1624                 headers = curl_slist_append(headers, h->data);
1625
1626         return headers;
1627 }
1628
1629 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1630 {
1631         char *ptr;
1632         CURLcode ret;
1633
1634         strbuf_reset(buf);
1635         ret = curl_easy_getinfo(curl, info, &ptr);
1636         if (!ret && ptr)
1637                 strbuf_addstr(buf, ptr);
1638         return ret;
1639 }
1640
1641 /*
1642  * Check for and extract a content-type parameter. "raw"
1643  * should be positioned at the start of the potential
1644  * parameter, with any whitespace already removed.
1645  *
1646  * "name" is the name of the parameter. The value is appended
1647  * to "out".
1648  */
1649 static int extract_param(const char *raw, const char *name,
1650                          struct strbuf *out)
1651 {
1652         size_t len = strlen(name);
1653
1654         if (strncasecmp(raw, name, len))
1655                 return -1;
1656         raw += len;
1657
1658         if (*raw != '=')
1659                 return -1;
1660         raw++;
1661
1662         while (*raw && !isspace(*raw) && *raw != ';')
1663                 strbuf_addch(out, *raw++);
1664         return 0;
1665 }
1666
1667 /*
1668  * Extract a normalized version of the content type, with any
1669  * spaces suppressed, all letters lowercased, and no trailing ";"
1670  * or parameters.
1671  *
1672  * Note that we will silently remove even invalid whitespace. For
1673  * example, "text / plain" is specifically forbidden by RFC 2616,
1674  * but "text/plain" is the only reasonable output, and this keeps
1675  * our code simple.
1676  *
1677  * If the "charset" argument is not NULL, store the value of any
1678  * charset parameter there.
1679  *
1680  * Example:
1681  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1682  *   "text / plain" -> "text/plain"
1683  */
1684 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1685                                  struct strbuf *charset)
1686 {
1687         const char *p;
1688
1689         strbuf_reset(type);
1690         strbuf_grow(type, raw->len);
1691         for (p = raw->buf; *p; p++) {
1692                 if (isspace(*p))
1693                         continue;
1694                 if (*p == ';') {
1695                         p++;
1696                         break;
1697                 }
1698                 strbuf_addch(type, tolower(*p));
1699         }
1700
1701         if (!charset)
1702                 return;
1703
1704         strbuf_reset(charset);
1705         while (*p) {
1706                 while (isspace(*p) || *p == ';')
1707                         p++;
1708                 if (!extract_param(p, "charset", charset))
1709                         return;
1710                 while (*p && !isspace(*p))
1711                         p++;
1712         }
1713
1714         if (!charset->len && starts_with(type->buf, "text/"))
1715                 strbuf_addstr(charset, "ISO-8859-1");
1716 }
1717
1718 static void write_accept_language(struct strbuf *buf)
1719 {
1720         /*
1721          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1722          * that, q-value will be smaller than 0.001, the minimum q-value the
1723          * HTTP specification allows. See
1724          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1725          */
1726         const int MAX_DECIMAL_PLACES = 3;
1727         const int MAX_LANGUAGE_TAGS = 1000;
1728         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1729         char **language_tags = NULL;
1730         int num_langs = 0;
1731         const char *s = get_preferred_languages();
1732         int i;
1733         struct strbuf tag = STRBUF_INIT;
1734
1735         /* Don't add Accept-Language header if no language is preferred. */
1736         if (!s)
1737                 return;
1738
1739         /*
1740          * Split the colon-separated string of preferred languages into
1741          * language_tags array.
1742          */
1743         do {
1744                 /* collect language tag */
1745                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1746                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1747
1748                 /* skip .codeset, @modifier and any other unnecessary parts */
1749                 while (*s && *s != ':')
1750                         s++;
1751
1752                 if (tag.len) {
1753                         num_langs++;
1754                         REALLOC_ARRAY(language_tags, num_langs);
1755                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1756                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1757                                 break;
1758                 }
1759         } while (*s++);
1760
1761         /* write Accept-Language header into buf */
1762         if (num_langs) {
1763                 int last_buf_len = 0;
1764                 int max_q;
1765                 int decimal_places;
1766                 char q_format[32];
1767
1768                 /* add '*' */
1769                 REALLOC_ARRAY(language_tags, num_langs + 1);
1770                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1771
1772                 /* compute decimal_places */
1773                 for (max_q = 1, decimal_places = 0;
1774                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1775                      decimal_places++, max_q *= 10)
1776                         ;
1777
1778                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1779
1780                 strbuf_addstr(buf, "Accept-Language: ");
1781
1782                 for (i = 0; i < num_langs; i++) {
1783                         if (i > 0)
1784                                 strbuf_addstr(buf, ", ");
1785
1786                         strbuf_addstr(buf, language_tags[i]);
1787
1788                         if (i > 0)
1789                                 strbuf_addf(buf, q_format, max_q - i);
1790
1791                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1792                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1793                                 break;
1794                         }
1795
1796                         last_buf_len = buf->len;
1797                 }
1798         }
1799
1800         /* free language tags -- last one is a static '*' */
1801         for (i = 0; i < num_langs - 1; i++)
1802                 free(language_tags[i]);
1803         free(language_tags);
1804 }
1805
1806 /*
1807  * Get an Accept-Language header which indicates user's preferred languages.
1808  *
1809  * Examples:
1810  *   LANGUAGE= -> ""
1811  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1812  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1813  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1814  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1815  *   LANGUAGE= LANG=C -> ""
1816  */
1817 static const char *get_accept_language(void)
1818 {
1819         if (!cached_accept_language) {
1820                 struct strbuf buf = STRBUF_INIT;
1821                 write_accept_language(&buf);
1822                 if (buf.len > 0)
1823                         cached_accept_language = strbuf_detach(&buf, NULL);
1824         }
1825
1826         return cached_accept_language;
1827 }
1828
1829 static void http_opt_request_remainder(CURL *curl, off_t pos)
1830 {
1831         char buf[128];
1832         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1833         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1834 }
1835
1836 /* http_request() targets */
1837 #define HTTP_REQUEST_STRBUF     0
1838 #define HTTP_REQUEST_FILE       1
1839
1840 static int http_request(const char *url,
1841                         void *result, int target,
1842                         const struct http_get_options *options)
1843 {
1844         struct active_request_slot *slot;
1845         struct slot_results results;
1846         struct curl_slist *headers = http_copy_default_headers();
1847         struct strbuf buf = STRBUF_INIT;
1848         const char *accept_language;
1849         int ret;
1850
1851         slot = get_active_slot();
1852         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1853
1854         if (result == NULL) {
1855                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1856         } else {
1857                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1858                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1859
1860                 if (target == HTTP_REQUEST_FILE) {
1861                         off_t posn = ftello(result);
1862                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1863                                          fwrite);
1864                         if (posn > 0)
1865                                 http_opt_request_remainder(slot->curl, posn);
1866                 } else
1867                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1868                                          fwrite_buffer);
1869         }
1870
1871         accept_language = get_accept_language();
1872
1873         if (accept_language)
1874                 headers = curl_slist_append(headers, accept_language);
1875
1876         strbuf_addstr(&buf, "Pragma:");
1877         if (options && options->no_cache)
1878                 strbuf_addstr(&buf, " no-cache");
1879         if (options && options->initial_request &&
1880             http_follow_config == HTTP_FOLLOW_INITIAL)
1881                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1882
1883         headers = curl_slist_append(headers, buf.buf);
1884
1885         /* Add additional headers here */
1886         if (options && options->extra_headers) {
1887                 const struct string_list_item *item;
1888                 for_each_string_list_item(item, options->extra_headers) {
1889                         headers = curl_slist_append(headers, item->string);
1890                 }
1891         }
1892
1893         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1894         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1895         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
1896         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1897
1898         ret = run_one_slot(slot, &results);
1899
1900         if (options && options->content_type) {
1901                 struct strbuf raw = STRBUF_INIT;
1902                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1903                 extract_content_type(&raw, options->content_type,
1904                                      options->charset);
1905                 strbuf_release(&raw);
1906         }
1907
1908         if (options && options->effective_url)
1909                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1910                                 options->effective_url);
1911
1912         curl_slist_free_all(headers);
1913         strbuf_release(&buf);
1914
1915         return ret;
1916 }
1917
1918 /*
1919  * Update the "base" url to a more appropriate value, as deduced by
1920  * redirects seen when requesting a URL starting with "url".
1921  *
1922  * The "asked" parameter is a URL that we asked curl to access, and must begin
1923  * with "base".
1924  *
1925  * The "got" parameter is the URL that curl reported to us as where we ended
1926  * up.
1927  *
1928  * Returns 1 if we updated the base url, 0 otherwise.
1929  *
1930  * Our basic strategy is to compare "base" and "asked" to find the bits
1931  * specific to our request. We then strip those bits off of "got" to yield the
1932  * new base. So for example, if our base is "http://example.com/foo.git",
1933  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1934  * with "https://other.example.com/foo.git/info/refs". We would want the
1935  * new URL to become "https://other.example.com/foo.git".
1936  *
1937  * Note that this assumes a sane redirect scheme. It's entirely possible
1938  * in the example above to end up at a URL that does not even end in
1939  * "info/refs".  In such a case we die. There's not much we can do, such a
1940  * scheme is unlikely to represent a real git repository, and failing to
1941  * rewrite the base opens options for malicious redirects to do funny things.
1942  */
1943 static int update_url_from_redirect(struct strbuf *base,
1944                                     const char *asked,
1945                                     const struct strbuf *got)
1946 {
1947         const char *tail;
1948         size_t new_len;
1949
1950         if (!strcmp(asked, got->buf))
1951                 return 0;
1952
1953         if (!skip_prefix(asked, base->buf, &tail))
1954                 BUG("update_url_from_redirect: %s is not a superset of %s",
1955                     asked, base->buf);
1956
1957         new_len = got->len;
1958         if (!strip_suffix_mem(got->buf, &new_len, tail))
1959                 die(_("unable to update url base from redirection:\n"
1960                       "  asked for: %s\n"
1961                       "   redirect: %s"),
1962                     asked, got->buf);
1963
1964         strbuf_reset(base);
1965         strbuf_add(base, got->buf, new_len);
1966
1967         return 1;
1968 }
1969
1970 static int http_request_reauth(const char *url,
1971                                void *result, int target,
1972                                struct http_get_options *options)
1973 {
1974         int ret = http_request(url, result, target, options);
1975
1976         if (ret != HTTP_OK && ret != HTTP_REAUTH)
1977                 return ret;
1978
1979         if (options && options->effective_url && options->base_url) {
1980                 if (update_url_from_redirect(options->base_url,
1981                                              url, options->effective_url)) {
1982                         credential_from_url(&http_auth, options->base_url->buf);
1983                         url = options->effective_url->buf;
1984                 }
1985         }
1986
1987         if (ret != HTTP_REAUTH)
1988                 return ret;
1989
1990         /*
1991          * The previous request may have put cruft into our output stream; we
1992          * should clear it out before making our next request.
1993          */
1994         switch (target) {
1995         case HTTP_REQUEST_STRBUF:
1996                 strbuf_reset(result);
1997                 break;
1998         case HTTP_REQUEST_FILE:
1999                 if (fflush(result)) {
2000                         error_errno("unable to flush a file");
2001                         return HTTP_START_FAILED;
2002                 }
2003                 rewind(result);
2004                 if (ftruncate(fileno(result), 0) < 0) {
2005                         error_errno("unable to truncate a file");
2006                         return HTTP_START_FAILED;
2007                 }
2008                 break;
2009         default:
2010                 BUG("Unknown http_request target");
2011         }
2012
2013         credential_fill(&http_auth);
2014
2015         return http_request(url, result, target, options);
2016 }
2017
2018 int http_get_strbuf(const char *url,
2019                     struct strbuf *result,
2020                     struct http_get_options *options)
2021 {
2022         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
2023 }
2024
2025 /*
2026  * Downloads a URL and stores the result in the given file.
2027  *
2028  * If a previous interrupted download is detected (i.e. a previous temporary
2029  * file is still around) the download is resumed.
2030  */
2031 static int http_get_file(const char *url, const char *filename,
2032                          struct http_get_options *options)
2033 {
2034         int ret;
2035         struct strbuf tmpfile = STRBUF_INIT;
2036         FILE *result;
2037
2038         strbuf_addf(&tmpfile, "%s.temp", filename);
2039         result = fopen(tmpfile.buf, "a");
2040         if (!result) {
2041                 error("Unable to open local file %s", tmpfile.buf);
2042                 ret = HTTP_ERROR;
2043                 goto cleanup;
2044         }
2045
2046         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
2047         fclose(result);
2048
2049         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
2050                 ret = HTTP_ERROR;
2051 cleanup:
2052         strbuf_release(&tmpfile);
2053         return ret;
2054 }
2055
2056 int http_fetch_ref(const char *base, struct ref *ref)
2057 {
2058         struct http_get_options options = {0};
2059         char *url;
2060         struct strbuf buffer = STRBUF_INIT;
2061         int ret = -1;
2062
2063         options.no_cache = 1;
2064
2065         url = quote_ref_url(base, ref->name);
2066         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
2067                 strbuf_rtrim(&buffer);
2068                 if (buffer.len == 40)
2069                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
2070                 else if (starts_with(buffer.buf, "ref: ")) {
2071                         ref->symref = xstrdup(buffer.buf + 5);
2072                         ret = 0;
2073                 }
2074         }
2075
2076         strbuf_release(&buffer);
2077         free(url);
2078         return ret;
2079 }
2080
2081 /* Helpers for fetching packs */
2082 static char *fetch_pack_index(unsigned char *sha1, const char *base_url)
2083 {
2084         char *url, *tmp;
2085         struct strbuf buf = STRBUF_INIT;
2086
2087         if (http_is_verbose)
2088                 fprintf(stderr, "Getting index for pack %s\n", sha1_to_hex(sha1));
2089
2090         end_url_with_slash(&buf, base_url);
2091         strbuf_addf(&buf, "objects/pack/pack-%s.idx", sha1_to_hex(sha1));
2092         url = strbuf_detach(&buf, NULL);
2093
2094         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(sha1));
2095         tmp = strbuf_detach(&buf, NULL);
2096
2097         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
2098                 error("Unable to get pack index %s", url);
2099                 FREE_AND_NULL(tmp);
2100         }
2101
2102         free(url);
2103         return tmp;
2104 }
2105
2106 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
2107         unsigned char *sha1, const char *base_url)
2108 {
2109         struct packed_git *new_pack;
2110         char *tmp_idx = NULL;
2111         int ret;
2112
2113         if (has_pack_index(sha1)) {
2114                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
2115                 if (!new_pack)
2116                         return -1; /* parse_pack_index() already issued error message */
2117                 goto add_pack;
2118         }
2119
2120         tmp_idx = fetch_pack_index(sha1, base_url);
2121         if (!tmp_idx)
2122                 return -1;
2123
2124         new_pack = parse_pack_index(sha1, tmp_idx);
2125         if (!new_pack) {
2126                 unlink(tmp_idx);
2127                 free(tmp_idx);
2128
2129                 return -1; /* parse_pack_index() already issued error message */
2130         }
2131
2132         ret = verify_pack_index(new_pack);
2133         if (!ret) {
2134                 close_pack_index(new_pack);
2135                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
2136         }
2137         free(tmp_idx);
2138         if (ret)
2139                 return -1;
2140
2141 add_pack:
2142         new_pack->next = *packs_head;
2143         *packs_head = new_pack;
2144         return 0;
2145 }
2146
2147 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
2148 {
2149         struct http_get_options options = {0};
2150         int ret = 0, i = 0;
2151         char *url, *data;
2152         struct strbuf buf = STRBUF_INIT;
2153         unsigned char hash[GIT_MAX_RAWSZ];
2154         const unsigned hexsz = the_hash_algo->hexsz;
2155
2156         end_url_with_slash(&buf, base_url);
2157         strbuf_addstr(&buf, "objects/info/packs");
2158         url = strbuf_detach(&buf, NULL);
2159
2160         options.no_cache = 1;
2161         ret = http_get_strbuf(url, &buf, &options);
2162         if (ret != HTTP_OK)
2163                 goto cleanup;
2164
2165         data = buf.buf;
2166         while (i < buf.len) {
2167                 switch (data[i]) {
2168                 case 'P':
2169                         i++;
2170                         if (i + hexsz + 12 <= buf.len &&
2171                             starts_with(data + i, " pack-") &&
2172                             starts_with(data + i + hexsz + 6, ".pack\n")) {
2173                                 get_sha1_hex(data + i + 6, hash);
2174                                 fetch_and_setup_pack_index(packs_head, hash,
2175                                                       base_url);
2176                                 i += hexsz + 11;
2177                                 break;
2178                         }
2179                 default:
2180                         while (i < buf.len && data[i] != '\n')
2181                                 i++;
2182                 }
2183                 i++;
2184         }
2185
2186 cleanup:
2187         free(url);
2188         return ret;
2189 }
2190
2191 void release_http_pack_request(struct http_pack_request *preq)
2192 {
2193         if (preq->packfile != NULL) {
2194                 fclose(preq->packfile);
2195                 preq->packfile = NULL;
2196         }
2197         preq->slot = NULL;
2198         strbuf_release(&preq->tmpfile);
2199         free(preq->url);
2200         free(preq);
2201 }
2202
2203 int finish_http_pack_request(struct http_pack_request *preq)
2204 {
2205         struct packed_git **lst;
2206         struct packed_git *p = preq->target;
2207         char *tmp_idx;
2208         size_t len;
2209         struct child_process ip = CHILD_PROCESS_INIT;
2210
2211         close_pack_index(p);
2212
2213         fclose(preq->packfile);
2214         preq->packfile = NULL;
2215
2216         lst = preq->lst;
2217         while (*lst != p)
2218                 lst = &((*lst)->next);
2219         *lst = (*lst)->next;
2220
2221         if (!strip_suffix(preq->tmpfile.buf, ".pack.temp", &len))
2222                 BUG("pack tmpfile does not end in .pack.temp?");
2223         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile.buf);
2224
2225         argv_array_push(&ip.args, "index-pack");
2226         argv_array_pushl(&ip.args, "-o", tmp_idx, NULL);
2227         argv_array_push(&ip.args, preq->tmpfile.buf);
2228         ip.git_cmd = 1;
2229         ip.no_stdin = 1;
2230         ip.no_stdout = 1;
2231
2232         if (run_command(&ip)) {
2233                 unlink(preq->tmpfile.buf);
2234                 unlink(tmp_idx);
2235                 free(tmp_idx);
2236                 return -1;
2237         }
2238
2239         unlink(sha1_pack_index_name(p->sha1));
2240
2241         if (finalize_object_file(preq->tmpfile.buf, sha1_pack_name(p->sha1))
2242          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->sha1))) {
2243                 free(tmp_idx);
2244                 return -1;
2245         }
2246
2247         install_packed_git(the_repository, p);
2248         free(tmp_idx);
2249         return 0;
2250 }
2251
2252 struct http_pack_request *new_http_pack_request(
2253         struct packed_git *target, const char *base_url)
2254 {
2255         off_t prev_posn = 0;
2256         struct strbuf buf = STRBUF_INIT;
2257         struct http_pack_request *preq;
2258
2259         preq = xcalloc(1, sizeof(*preq));
2260         strbuf_init(&preq->tmpfile, 0);
2261         preq->target = target;
2262
2263         end_url_with_slash(&buf, base_url);
2264         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
2265                 sha1_to_hex(target->sha1));
2266         preq->url = strbuf_detach(&buf, NULL);
2267
2268         strbuf_addf(&preq->tmpfile, "%s.temp", sha1_pack_name(target->sha1));
2269         preq->packfile = fopen(preq->tmpfile.buf, "a");
2270         if (!preq->packfile) {
2271                 error("Unable to open local file %s for pack",
2272                       preq->tmpfile.buf);
2273                 goto abort;
2274         }
2275
2276         preq->slot = get_active_slot();
2277         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
2278         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
2279         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
2280         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
2281                 no_pragma_header);
2282
2283         /*
2284          * If there is data present from a previous transfer attempt,
2285          * resume where it left off
2286          */
2287         prev_posn = ftello(preq->packfile);
2288         if (prev_posn>0) {
2289                 if (http_is_verbose)
2290                         fprintf(stderr,
2291                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
2292                                 sha1_to_hex(target->sha1), (uintmax_t)prev_posn);
2293                 http_opt_request_remainder(preq->slot->curl, prev_posn);
2294         }
2295
2296         return preq;
2297
2298 abort:
2299         strbuf_release(&preq->tmpfile);
2300         free(preq->url);
2301         free(preq);
2302         return NULL;
2303 }
2304
2305 /* Helpers for fetching objects (loose) */
2306 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
2307                                void *data)
2308 {
2309         unsigned char expn[4096];
2310         size_t size = eltsize * nmemb;
2311         int posn = 0;
2312         struct http_object_request *freq = data;
2313         struct active_request_slot *slot = freq->slot;
2314
2315         if (slot) {
2316                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
2317                                                 &slot->http_code);
2318                 if (c != CURLE_OK)
2319                         BUG("curl_easy_getinfo for HTTP code failed: %s",
2320                                 curl_easy_strerror(c));
2321                 if (slot->http_code >= 300)
2322                         return size;
2323         }
2324
2325         do {
2326                 ssize_t retval = xwrite(freq->localfile,
2327                                         (char *) ptr + posn, size - posn);
2328                 if (retval < 0)
2329                         return posn;
2330                 posn += retval;
2331         } while (posn < size);
2332
2333         freq->stream.avail_in = size;
2334         freq->stream.next_in = (void *)ptr;
2335         do {
2336                 freq->stream.next_out = expn;
2337                 freq->stream.avail_out = sizeof(expn);
2338                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
2339                 git_SHA1_Update(&freq->c, expn,
2340                                 sizeof(expn) - freq->stream.avail_out);
2341         } while (freq->stream.avail_in && freq->zret == Z_OK);
2342         return size;
2343 }
2344
2345 struct http_object_request *new_http_object_request(const char *base_url,
2346                                                     const struct object_id *oid)
2347 {
2348         char *hex = oid_to_hex(oid);
2349         struct strbuf filename = STRBUF_INIT;
2350         struct strbuf prevfile = STRBUF_INIT;
2351         int prevlocal;
2352         char prev_buf[PREV_BUF_SIZE];
2353         ssize_t prev_read = 0;
2354         off_t prev_posn = 0;
2355         struct http_object_request *freq;
2356
2357         freq = xcalloc(1, sizeof(*freq));
2358         strbuf_init(&freq->tmpfile, 0);
2359         oidcpy(&freq->oid, oid);
2360         freq->localfile = -1;
2361
2362         loose_object_path(the_repository, &filename, oid);
2363         strbuf_addf(&freq->tmpfile, "%s.temp", filename.buf);
2364
2365         strbuf_addf(&prevfile, "%s.prev", filename.buf);
2366         unlink_or_warn(prevfile.buf);
2367         rename(freq->tmpfile.buf, prevfile.buf);
2368         unlink_or_warn(freq->tmpfile.buf);
2369         strbuf_release(&filename);
2370
2371         if (freq->localfile != -1)
2372                 error("fd leakage in start: %d", freq->localfile);
2373         freq->localfile = open(freq->tmpfile.buf,
2374                                O_WRONLY | O_CREAT | O_EXCL, 0666);
2375         /*
2376          * This could have failed due to the "lazy directory creation";
2377          * try to mkdir the last path component.
2378          */
2379         if (freq->localfile < 0 && errno == ENOENT) {
2380                 char *dir = strrchr(freq->tmpfile.buf, '/');
2381                 if (dir) {
2382                         *dir = 0;
2383                         mkdir(freq->tmpfile.buf, 0777);
2384                         *dir = '/';
2385                 }
2386                 freq->localfile = open(freq->tmpfile.buf,
2387                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
2388         }
2389
2390         if (freq->localfile < 0) {
2391                 error_errno("Couldn't create temporary file %s",
2392                             freq->tmpfile.buf);
2393                 goto abort;
2394         }
2395
2396         git_inflate_init(&freq->stream);
2397
2398         git_SHA1_Init(&freq->c);
2399
2400         freq->url = get_remote_object_url(base_url, hex, 0);
2401
2402         /*
2403          * If a previous temp file is present, process what was already
2404          * fetched.
2405          */
2406         prevlocal = open(prevfile.buf, O_RDONLY);
2407         if (prevlocal != -1) {
2408                 do {
2409                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
2410                         if (prev_read>0) {
2411                                 if (fwrite_sha1_file(prev_buf,
2412                                                      1,
2413                                                      prev_read,
2414                                                      freq) == prev_read) {
2415                                         prev_posn += prev_read;
2416                                 } else {
2417                                         prev_read = -1;
2418                                 }
2419                         }
2420                 } while (prev_read > 0);
2421                 close(prevlocal);
2422         }
2423         unlink_or_warn(prevfile.buf);
2424         strbuf_release(&prevfile);
2425
2426         /*
2427          * Reset inflate/SHA1 if there was an error reading the previous temp
2428          * file; also rewind to the beginning of the local file.
2429          */
2430         if (prev_read == -1) {
2431                 memset(&freq->stream, 0, sizeof(freq->stream));
2432                 git_inflate_init(&freq->stream);
2433                 git_SHA1_Init(&freq->c);
2434                 if (prev_posn>0) {
2435                         prev_posn = 0;
2436                         lseek(freq->localfile, 0, SEEK_SET);
2437                         if (ftruncate(freq->localfile, 0) < 0) {
2438                                 error_errno("Couldn't truncate temporary file %s",
2439                                             freq->tmpfile.buf);
2440                                 goto abort;
2441                         }
2442                 }
2443         }
2444
2445         freq->slot = get_active_slot();
2446
2447         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2448         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2449         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2450         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2451         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2452         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2453
2454         /*
2455          * If we have successfully processed data from a previous fetch
2456          * attempt, only fetch the data we don't already have.
2457          */
2458         if (prev_posn>0) {
2459                 if (http_is_verbose)
2460                         fprintf(stderr,
2461                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2462                                 hex, (uintmax_t)prev_posn);
2463                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2464         }
2465
2466         return freq;
2467
2468 abort:
2469         strbuf_release(&prevfile);
2470         free(freq->url);
2471         free(freq);
2472         return NULL;
2473 }
2474
2475 void process_http_object_request(struct http_object_request *freq)
2476 {
2477         if (freq->slot == NULL)
2478                 return;
2479         freq->curl_result = freq->slot->curl_result;
2480         freq->http_code = freq->slot->http_code;
2481         freq->slot = NULL;
2482 }
2483
2484 int finish_http_object_request(struct http_object_request *freq)
2485 {
2486         struct stat st;
2487         struct strbuf filename = STRBUF_INIT;
2488
2489         close(freq->localfile);
2490         freq->localfile = -1;
2491
2492         process_http_object_request(freq);
2493
2494         if (freq->http_code == 416) {
2495                 warning("requested range invalid; we may already have all the data.");
2496         } else if (freq->curl_result != CURLE_OK) {
2497                 if (stat(freq->tmpfile.buf, &st) == 0)
2498                         if (st.st_size == 0)
2499                                 unlink_or_warn(freq->tmpfile.buf);
2500                 return -1;
2501         }
2502
2503         git_inflate_end(&freq->stream);
2504         git_SHA1_Final(freq->real_oid.hash, &freq->c);
2505         if (freq->zret != Z_STREAM_END) {
2506                 unlink_or_warn(freq->tmpfile.buf);
2507                 return -1;
2508         }
2509         if (!oideq(&freq->oid, &freq->real_oid)) {
2510                 unlink_or_warn(freq->tmpfile.buf);
2511                 return -1;
2512         }
2513         loose_object_path(the_repository, &filename, &freq->oid);
2514         freq->rename = finalize_object_file(freq->tmpfile.buf, filename.buf);
2515         strbuf_release(&filename);
2516
2517         return freq->rename;
2518 }
2519
2520 void abort_http_object_request(struct http_object_request *freq)
2521 {
2522         unlink_or_warn(freq->tmpfile.buf);
2523
2524         release_http_object_request(freq);
2525 }
2526
2527 void release_http_object_request(struct http_object_request *freq)
2528 {
2529         if (freq->localfile != -1) {
2530                 close(freq->localfile);
2531                 freq->localfile = -1;
2532         }
2533         FREE_AND_NULL(freq->url);
2534         if (freq->slot != NULL) {
2535                 freq->slot->callback_func = NULL;
2536                 freq->slot->callback_data = NULL;
2537                 release_active_slot(freq->slot);
2538                 freq->slot = NULL;
2539         }
2540         strbuf_release(&freq->tmpfile);
2541 }