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 string_list extra_http_headers = STRING_LIST_INIT_DUP;
 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 / eltsize;
 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 nmemb;
 208 }
 209
 210 size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 211 {
 212         return 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                         string_list_clear(&extra_http_headers, 0);
 418                 } else {
 419                         string_list_append(&extra_http_headers, value);
 420                 }
 421                 return 0;
 422         }
 423
 424         if (!strcmp("http.followredirects", var)) {
 425                 if (value && !strcmp(value, "initial"))
 426                         http_follow_config = HTTP_FOLLOW_INITIAL;
 427                 else if (git_config_bool(var, value))
 428                         http_follow_config = HTTP_FOLLOW_ALWAYS;
 429                 else
 430                         http_follow_config = HTTP_FOLLOW_NONE;
 431                 return 0;
 432         }
 433
 434         /* Fall back on the default ones */
 435         return git_default_config(var, value, cb);
 436 }
 437
 438 static int curl_empty_auth_enabled(void)
 439 {
 440         if (curl_empty_auth >= 0)
 441                 return curl_empty_auth;
 442
 443 #ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
 444         /*
 445          * Our libcurl is too old to do AUTH_ANY in the first place;
 446          * just default to turning the feature off.
 447          */
 448 #else
 449         /*
 450          * In the automatic case, kick in the empty-auth
 451          * hack as long as we would potentially try some
 452          * method more exotic than "Basic" or "Digest".
 453          *
 454          * But only do this when this is our second or
 455          * subsequent request, as by then we know what
 456          * methods are available.
 457          */
 458         if (http_auth_methods_restricted &&
 459             (http_auth_methods & ~empty_auth_useless))
 460                 return 1;
 461 #endif
 462         return 0;
 463 }
 464
 465 static void init_curl_http_auth(CURL *result)
 466 {
 467         if (!http_auth.username || !*http_auth.username) {
 468                 if (curl_empty_auth_enabled())
 469                         curl_easy_setopt(result, CURLOPT_USERPWD, ":");
 470                 return;
 471         }
 472
 473         credential_fill(&http_auth);
 474
 475 #if LIBCURL_VERSION_NUM >= 0x071301
 476         curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 477         curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 478 #else
 479         {
 480                 static struct strbuf up = STRBUF_INIT;
 481                 /*
 482                  * Note that we assume we only ever have a single set of
 483                  * credentials in a given program run, so we do not have
 484                  * to worry about updating this buffer, only setting its
 485                  * initial value.
 486                  */
 487                 if (!up.len)
 488                         strbuf_addf(&up, "%s:%s",
 489                                 http_auth.username, http_auth.password);
 490                 curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 491         }
 492 #endif
 493 }
 494
 495 /* *var must be free-able */
 496 static void var_override(const char **var, char *value)
 497 {
 498         if (value) {
 499                 free((void *)*var);
 500                 *var = xstrdup(value);
 501         }
 502 }
 503
 504 static void set_proxyauth_name_password(CURL *result)
 505 {
 506 #if LIBCURL_VERSION_NUM >= 0x071301
 507                 curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
 508                         proxy_auth.username);
 509                 curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
 510                         proxy_auth.password);
 511 #else
 512                 struct strbuf s = STRBUF_INIT;
 513
 514                 strbuf_addstr_urlencode(&s, proxy_auth.username,
 515                                         is_rfc3986_unreserved);
 516                 strbuf_addch(&s, ':');
 517                 strbuf_addstr_urlencode(&s, proxy_auth.password,
 518                                         is_rfc3986_unreserved);
 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.host = xstrdup("");
 562                 cert_auth.username = xstrdup("");
 563                 cert_auth.path = xstrdup(ssl_cert);
 564                 credential_fill(&cert_auth);
 565         }
 566         return 1;
 567 }
 568
 569 #if LIBCURL_VERSION_NUM >= 0x071900
 570 static void set_curl_keepalive(CURL *c)
 571 {
 572         curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 573 }
 574
 575 #elif LIBCURL_VERSION_NUM >= 0x071000
 576 static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 577 {
 578         int ka = 1;
 579         int rc;
 580         socklen_t len = (socklen_t)sizeof(ka);
 581
 582         if (type != CURLSOCKTYPE_IPCXN)
 583                 return 0;
 584
 585         rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 586         if (rc < 0)
 587                 warning_errno("unable to set SO_KEEPALIVE on socket");
 588
 589         return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 590 }
 591
 592 static void set_curl_keepalive(CURL *c)
 593 {
 594         curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 595 }
 596
 597 #else
 598 static void set_curl_keepalive(CURL *c)
 599 {
 600         /* not supported on older curl versions */
 601 }
 602 #endif
 603
 604 static void redact_sensitive_header(struct strbuf *header)
 605 {
 606         const char *sensitive_header;
 607
 608         if (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
 609             skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header)) {
 610                 /* The first token is the type, which is OK to log */
 611                 while (isspace(*sensitive_header))
 612                         sensitive_header++;
 613                 while (*sensitive_header && !isspace(*sensitive_header))
 614                         sensitive_header++;
 615                 /* Everything else is opaque and possibly sensitive */
 616                 strbuf_setlen(header,  sensitive_header - header->buf);
 617                 strbuf_addstr(header, " <redacted>");
 618         } else if (cookies_to_redact.nr &&
 619                    skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
 620                 struct strbuf redacted_header = STRBUF_INIT;
 621                 char *cookie;
 622
 623                 while (isspace(*sensitive_header))
 624                         sensitive_header++;
 625
 626                 /*
 627                  * The contents of header starting from sensitive_header will
 628                  * subsequently be overridden, so it is fine to mutate this
 629                  * string (hence the assignment to "char *").
 630                  */
 631                 cookie = (char *) sensitive_header;
 632
 633                 while (cookie) {
 634                         char *equals;
 635                         char *semicolon = strstr(cookie, "; ");
 636                         if (semicolon)
 637                                 *semicolon = 0;
 638                         equals = strchrnul(cookie, '=');
 639                         if (!equals) {
 640                                 /* invalid cookie, just append and continue */
 641                                 strbuf_addstr(&redacted_header, cookie);
 642                                 continue;
 643                         }
 644                         *equals = 0; /* temporarily set to NUL for lookup */
 645                         if (string_list_lookup(&cookies_to_redact, cookie)) {
 646                                 strbuf_addstr(&redacted_header, cookie);
 647                                 strbuf_addstr(&redacted_header, "=<redacted>");
 648                         } else {
 649                                 *equals = '=';
 650                                 strbuf_addstr(&redacted_header, cookie);
 651                         }
 652                         if (semicolon) {
 653                                 /*
 654                                  * There are more cookies. (Or, for some
 655                                  * reason, the input string ends in "; ".)
 656                                  */
 657                                 strbuf_addstr(&redacted_header, "; ");
 658                                 cookie = semicolon + strlen("; ");
 659                         } else {
 660                                 cookie = NULL;
 661                         }
 662                 }
 663
 664                 strbuf_setlen(header, sensitive_header - header->buf);
 665                 strbuf_addbuf(header, &redacted_header);
 666         }
 667 }
 668
 669 static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
 670 {
 671         struct strbuf out = STRBUF_INIT;
 672         struct strbuf **headers, **header;
 673
 674         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 675                 text, (long)size, (long)size);
 676         trace_strbuf(&trace_curl, &out);
 677         strbuf_reset(&out);
 678         strbuf_add(&out, ptr, size);
 679         headers = strbuf_split_max(&out, '\n', 0);
 680
 681         for (header = headers; *header; header++) {
 682                 if (hide_sensitive_header)
 683                         redact_sensitive_header(*header);
 684                 strbuf_insertstr((*header), 0, text);
 685                 strbuf_insertstr((*header), strlen(text), ": ");
 686                 strbuf_rtrim((*header));
 687                 strbuf_addch((*header), '\n');
 688                 trace_strbuf(&trace_curl, (*header));
 689         }
 690         strbuf_list_free(headers);
 691         strbuf_release(&out);
 692 }
 693
 694 static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
 695 {
 696         size_t i;
 697         struct strbuf out = STRBUF_INIT;
 698         unsigned int width = 60;
 699
 700         strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 701                 text, (long)size, (long)size);
 702         trace_strbuf(&trace_curl, &out);
 703
 704         for (i = 0; i < size; i += width) {
 705                 size_t w;
 706
 707                 strbuf_reset(&out);
 708                 strbuf_addf(&out, "%s: ", text);
 709                 for (w = 0; (w < width) && (i + w < size); w++) {
 710                         unsigned char ch = ptr[i + w];
 711
 712                         strbuf_addch(&out,
 713                                        (ch >= 0x20) && (ch < 0x80)
 714                                        ? ch : '.');
 715                 }
 716                 strbuf_addch(&out, '\n');
 717                 trace_strbuf(&trace_curl, &out);
 718         }
 719         strbuf_release(&out);
 720 }
 721
 722 static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
 723 {
 724         const char *text;
 725         enum { NO_FILTER = 0, DO_FILTER = 1 };
 726
 727         switch (type) {
 728         case CURLINFO_TEXT:
 729                 trace_printf_key(&trace_curl, "== Info: %s", data);
 730                 break;
 731         case CURLINFO_HEADER_OUT:
 732                 text = "=> Send header";
 733                 curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
 734                 break;
 735         case CURLINFO_DATA_OUT:
 736                 if (trace_curl_data) {
 737                         text = "=> Send data";
 738                         curl_dump_data(text, (unsigned char *)data, size);
 739                 }
 740                 break;
 741         case CURLINFO_SSL_DATA_OUT:
 742                 if (trace_curl_data) {
 743                         text = "=> Send SSL data";
 744                         curl_dump_data(text, (unsigned char *)data, size);
 745                 }
 746                 break;
 747         case CURLINFO_HEADER_IN:
 748                 text = "<= Recv header";
 749                 curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
 750                 break;
 751         case CURLINFO_DATA_IN:
 752                 if (trace_curl_data) {
 753                         text = "<= Recv data";
 754                         curl_dump_data(text, (unsigned char *)data, size);
 755                 }
 756                 break;
 757         case CURLINFO_SSL_DATA_IN:
 758                 if (trace_curl_data) {
 759                         text = "<= Recv SSL data";
 760                         curl_dump_data(text, (unsigned char *)data, size);
 761                 }
 762                 break;
 763
 764         default:                /* we ignore unknown types by default */
 765                 return 0;
 766         }
 767         return 0;
 768 }
 769
 770 void setup_curl_trace(CURL *handle)
 771 {
 772         if (!trace_want(&trace_curl))
 773                 return;
 774         curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
 775         curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
 776         curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
 777 }
 778
 779 #ifdef CURLPROTO_HTTP
 780 static long get_curl_allowed_protocols(int from_user)
 781 {
 782         long allowed_protocols = 0;
 783
 784         if (is_transport_allowed("http", from_user))
 785                 allowed_protocols |= CURLPROTO_HTTP;
 786         if (is_transport_allowed("https", from_user))
 787                 allowed_protocols |= CURLPROTO_HTTPS;
 788         if (is_transport_allowed("ftp", from_user))
 789                 allowed_protocols |= CURLPROTO_FTP;
 790         if (is_transport_allowed("ftps", from_user))
 791                 allowed_protocols |= CURLPROTO_FTPS;
 792
 793         return allowed_protocols;
 794 }
 795 #endif
 796
 797 #if LIBCURL_VERSION_NUM >=0x072f00
 798 static int get_curl_http_version_opt(const char *version_string, long *opt)
 799 {
 800         int i;
 801         static struct {
 802                 const char *name;
 803                 long opt_token;
 804         } choice[] = {
 805                 { "HTTP/1.1", CURL_HTTP_VERSION_1_1 },
 806                 { "HTTP/2", CURL_HTTP_VERSION_2 }
 807         };
 808
 809         for (i = 0; i < ARRAY_SIZE(choice); i++) {
 810                 if (!strcmp(version_string, choice[i].name)) {
 811                         *opt = choice[i].opt_token;
 812                         return 0;
 813                 }
 814         }
 815
 816         warning("unknown value given to http.version: '%s'", version_string);
 817         return -1; /* not found */
 818 }
 819
 820 #endif
 821
 822 static CURL *get_curl_handle(void)
 823 {
 824         CURL *result = curl_easy_init();
 825
 826         if (!result)
 827                 die("curl_easy_init failed");
 828
 829         if (!curl_ssl_verify) {
 830                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 831                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 832         } else {
 833                 /* Verify authenticity of the peer's certificate */
 834                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 835                 /* The name in the cert must match whom we tried to connect */
 836                 curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 837         }
 838
 839 #if LIBCURL_VERSION_NUM >= 0x072f00 // 7.47.0
 840     if (curl_http_version) {
 841                 long opt;
 842                 if (!get_curl_http_version_opt(curl_http_version, &opt)) {
 843                         /* Set request use http version */
 844                         curl_easy_setopt(result, CURLOPT_HTTP_VERSION, opt);
 845                 }
 846     }
 847 #endif
 848
 849 #if LIBCURL_VERSION_NUM >= 0x070907
 850         curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 851 #endif
 852 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 853         curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 854 #endif
 855
 856 #ifdef CURLGSSAPI_DELEGATION_FLAG
 857         if (curl_deleg) {
 858                 int i;
 859                 for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
 860                         if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
 861                                 curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
 862                                                 curl_deleg_levels[i].curl_deleg_param);
 863                                 break;
 864                         }
 865                 }
 866                 if (i == ARRAY_SIZE(curl_deleg_levels))
 867                         warning("Unknown delegation method '%s': using default",
 868                                 curl_deleg);
 869         }
 870 #endif
 871
 872         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 873             !http_schannel_check_revoke) {
 874 #if LIBCURL_VERSION_NUM >= 0x072c00
 875                 curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
 876 #else
 877                 warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
 878 #endif
 879         }
 880
 881         if (http_proactive_auth)
 882                 init_curl_http_auth(result);
 883
 884         if (getenv("GIT_SSL_VERSION"))
 885                 ssl_version = getenv("GIT_SSL_VERSION");
 886         if (ssl_version && *ssl_version) {
 887                 int i;
 888                 for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 889                         if (!strcmp(ssl_version, sslversions[i].name)) {
 890                                 curl_easy_setopt(result, CURLOPT_SSLVERSION,
 891                                                  sslversions[i].ssl_version);
 892                                 break;
 893                         }
 894                 }
 895                 if (i == ARRAY_SIZE(sslversions))
 896                         warning("unsupported ssl version %s: using default",
 897                                 ssl_version);
 898         }
 899
 900         if (getenv("GIT_SSL_CIPHER_LIST"))
 901                 ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 902         if (ssl_cipherlist != NULL && *ssl_cipherlist)
 903                 curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 904                                 ssl_cipherlist);
 905
 906         if (ssl_cert != NULL)
 907                 curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 908         if (has_cert_password())
 909                 curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 910 #if LIBCURL_VERSION_NUM >= 0x070903
 911         if (ssl_key != NULL)
 912                 curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 913 #endif
 914 #if LIBCURL_VERSION_NUM >= 0x070908
 915         if (ssl_capath != NULL)
 916                 curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 917 #endif
 918 #if LIBCURL_VERSION_NUM >= 0x072c00
 919         if (ssl_pinnedkey != NULL)
 920                 curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 921 #endif
 922         if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 923             !http_schannel_use_ssl_cainfo) {
 924                 curl_easy_setopt(result, CURLOPT_CAINFO, NULL);
 925 #if LIBCURL_VERSION_NUM >= 0x073400
 926                 curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, NULL);
 927 #endif
 928         } else if (ssl_cainfo != NULL)
 929                 curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 930
 931         if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 932                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 933                                  curl_low_speed_limit);
 934                 curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 935                                  curl_low_speed_time);
 936         }
 937
 938         curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 939 #if LIBCURL_VERSION_NUM >= 0x071301
 940         curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 941 #elif LIBCURL_VERSION_NUM >= 0x071101
 942         curl_easy_setopt(result, CURLOPT_POST301, 1);
 943 #endif
 944 #ifdef CURLPROTO_HTTP
 945         curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
 946                          get_curl_allowed_protocols(0));
 947         curl_easy_setopt(result, CURLOPT_PROTOCOLS,
 948                          get_curl_allowed_protocols(-1));
 949 #else
 950         warning(_("Protocol restrictions not supported with cURL < 7.19.4"));
 951 #endif
 952         if (getenv("GIT_CURL_VERBOSE"))
 953                 curl_easy_setopt(result, CURLOPT_VERBOSE, 1L);
 954         setup_curl_trace(result);
 955         if (getenv("GIT_TRACE_CURL_NO_DATA"))
 956                 trace_curl_data = 0;
 957         if (getenv("GIT_REDACT_COOKIES")) {
 958                 string_list_split(&cookies_to_redact,
 959                                   getenv("GIT_REDACT_COOKIES"), ',', -1);
 960                 string_list_sort(&cookies_to_redact);
 961         }
 962
 963         curl_easy_setopt(result, CURLOPT_USERAGENT,
 964                 user_agent ? user_agent : git_user_agent());
 965
 966         if (curl_ftp_no_epsv)
 967                 curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 968
 969 #ifdef CURLOPT_USE_SSL
 970         if (curl_ssl_try)
 971                 curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 972 #endif
 973
 974         /*
 975          * CURL also examines these variables as a fallback; but we need to query
 976          * them here in order to decide whether to prompt for missing password (cf.
 977          * init_curl_proxy_auth()).
 978          *
 979          * Unlike many other common environment variables, these are historically
 980          * lowercase only. It appears that CURL did not know this and implemented
 981          * only uppercase variants, which was later corrected to take both - with
 982          * the exception of http_proxy, which is lowercase only also in CURL. As
 983          * the lowercase versions are the historical quasi-standard, they take
 984          * precedence here, as in CURL.
 985          */
 986         if (!curl_http_proxy) {
 987                 if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
 988                         var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
 989                         var_override(&curl_http_proxy, getenv("https_proxy"));
 990                 } else {
 991                         var_override(&curl_http_proxy, getenv("http_proxy"));
 992                 }
 993                 if (!curl_http_proxy) {
 994                         var_override(&curl_http_proxy, getenv("ALL_PROXY"));
 995                         var_override(&curl_http_proxy, getenv("all_proxy"));
 996                 }
 997         }
 998
 999         if (curl_http_proxy && curl_http_proxy[0] == '\0') {
1000                 /*
1001                  * Handle case with the empty http.proxy value here to keep
1002                  * common code clean.
1003                  * NB: empty option disables proxying at all.
1004                  */
1005                 curl_easy_setopt(result, CURLOPT_PROXY, "");
1006         } else if (curl_http_proxy) {
1007 #if LIBCURL_VERSION_NUM >= 0x071800
1008                 if (starts_with(curl_http_proxy, "socks5h"))
1009                         curl_easy_setopt(result,
1010                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
1011                 else if (starts_with(curl_http_proxy, "socks5"))
1012                         curl_easy_setopt(result,
1013                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
1014                 else if (starts_with(curl_http_proxy, "socks4a"))
1015                         curl_easy_setopt(result,
1016                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
1017                 else if (starts_with(curl_http_proxy, "socks"))
1018                         curl_easy_setopt(result,
1019                                 CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
1020 #endif
1021 #if LIBCURL_VERSION_NUM >= 0x073400
1022                 else if (starts_with(curl_http_proxy, "https"))
1023                         curl_easy_setopt(result,
1024                                 CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
1025 #endif
1026                 if (strstr(curl_http_proxy, "://"))
1027                         credential_from_url(&proxy_auth, curl_http_proxy);
1028                 else {
1029                         struct strbuf url = STRBUF_INIT;
1030                         strbuf_addf(&url, "http://%s", curl_http_proxy);
1031                         credential_from_url(&proxy_auth, url.buf);
1032                         strbuf_release(&url);
1033                 }
1034
1035                 if (!proxy_auth.host)
1036                         die("Invalid proxy URL '%s'", curl_http_proxy);
1037
1038                 curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
1039 #if LIBCURL_VERSION_NUM >= 0x071304
1040                 var_override(&curl_no_proxy, getenv("NO_PROXY"));
1041                 var_override(&curl_no_proxy, getenv("no_proxy"));
1042                 curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
1043 #endif
1044         }
1045         init_curl_proxy_auth(result);
1046
1047         set_curl_keepalive(result);
1048
1049         return result;
1050 }
1051
1052 static void set_from_env(const char **var, const char *envname)
1053 {
1054         const char *val = getenv(envname);
1055         if (val)
1056                 *var = val;
1057 }
1058
1059 void http_init(struct remote *remote, const char *url, int proactive_auth)
1060 {
1061         char *low_speed_limit;
1062         char *low_speed_time;
1063         char *normalized_url;
1064         struct urlmatch_config config = { STRING_LIST_INIT_DUP };
1065
1066         config.section = "http";
1067         config.key = NULL;
1068         config.collect_fn = http_options;
1069         config.cascade_fn = git_default_config;
1070         config.cb = NULL;
1071
1072         http_is_verbose = 0;
1073         normalized_url = url_normalize(url, &config.url);
1074
1075         git_config(urlmatch_config_entry, &config);
1076         free(normalized_url);
1077         string_list_clear(&config.vars, 1);
1078
1079 #if LIBCURL_VERSION_NUM >= 0x073800
1080         if (http_ssl_backend) {
1081                 const curl_ssl_backend **backends;
1082                 struct strbuf buf = STRBUF_INIT;
1083                 int i;
1084
1085                 switch (curl_global_sslset(-1, http_ssl_backend, &backends)) {
1086                 case CURLSSLSET_UNKNOWN_BACKEND:
1087                         strbuf_addf(&buf, _("Unsupported SSL backend '%s'. "
1088                                             "Supported SSL backends:"),
1089                                             http_ssl_backend);
1090                         for (i = 0; backends[i]; i++)
1091                                 strbuf_addf(&buf, "\n\t%s", backends[i]->name);
1092                         die("%s", buf.buf);
1093                 case CURLSSLSET_NO_BACKENDS:
1094                         die(_("Could not set SSL backend to '%s': "
1095                               "cURL was built without SSL backends"),
1096                             http_ssl_backend);
1097                 case CURLSSLSET_TOO_LATE:
1098                         die(_("Could not set SSL backend to '%s': already set"),
1099                             http_ssl_backend);
1100                 case CURLSSLSET_OK:
1101                         break; /* Okay! */
1102                 }
1103         }
1104 #endif
1105
1106         if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK)
1107                 die("curl_global_init failed");
1108
1109         http_proactive_auth = proactive_auth;
1110
1111         if (remote && remote->http_proxy)
1112                 curl_http_proxy = xstrdup(remote->http_proxy);
1113
1114         if (remote)
1115                 var_override(&http_proxy_authmethod, remote->http_proxy_authmethod);
1116
1117         pragma_header = curl_slist_append(http_copy_default_headers(),
1118                 "Pragma: no-cache");
1119         no_pragma_header = curl_slist_append(http_copy_default_headers(),
1120                 "Pragma:");
1121
1122 #ifdef USE_CURL_MULTI
1123         {
1124                 char *http_max_requests = getenv("GIT_HTTP_MAX_REQUESTS");
1125                 if (http_max_requests != NULL)
1126                         max_requests = atoi(http_max_requests);
1127         }
1128
1129         curlm = curl_multi_init();
1130         if (!curlm)
1131                 die("curl_multi_init failed");
1132 #endif
1133
1134         if (getenv("GIT_SSL_NO_VERIFY"))
1135                 curl_ssl_verify = 0;
1136
1137         set_from_env(&ssl_cert, "GIT_SSL_CERT");
1138 #if LIBCURL_VERSION_NUM >= 0x070903
1139         set_from_env(&ssl_key, "GIT_SSL_KEY");
1140 #endif
1141 #if LIBCURL_VERSION_NUM >= 0x070908
1142         set_from_env(&ssl_capath, "GIT_SSL_CAPATH");
1143 #endif
1144         set_from_env(&ssl_cainfo, "GIT_SSL_CAINFO");
1145
1146         set_from_env(&user_agent, "GIT_HTTP_USER_AGENT");
1147
1148         low_speed_limit = getenv("GIT_HTTP_LOW_SPEED_LIMIT");
1149         if (low_speed_limit != NULL)
1150                 curl_low_speed_limit = strtol(low_speed_limit, NULL, 10);
1151         low_speed_time = getenv("GIT_HTTP_LOW_SPEED_TIME");
1152         if (low_speed_time != NULL)
1153                 curl_low_speed_time = strtol(low_speed_time, NULL, 10);
1154
1155         if (curl_ssl_verify == -1)
1156                 curl_ssl_verify = 1;
1157
1158         curl_session_count = 0;
1159 #ifdef USE_CURL_MULTI
1160         if (max_requests < 1)
1161                 max_requests = DEFAULT_MAX_REQUESTS;
1162 #endif
1163
1164         if (getenv("GIT_CURL_FTP_NO_EPSV"))
1165                 curl_ftp_no_epsv = 1;
1166
1167         if (url) {
1168                 credential_from_url(&http_auth, url);
1169                 if (!ssl_cert_password_required &&
1170                     getenv("GIT_SSL_CERT_PASSWORD_PROTECTED") &&
1171                     starts_with(url, "https://"))
1172                         ssl_cert_password_required = 1;
1173         }
1174
1175 #ifndef NO_CURL_EASY_DUPHANDLE
1176         curl_default = get_curl_handle();
1177 #endif
1178 }
1179
1180 void http_cleanup(void)
1181 {
1182         struct active_request_slot *slot = active_queue_head;
1183
1184         while (slot != NULL) {
1185                 struct active_request_slot *next = slot->next;
1186                 if (slot->curl != NULL) {
1187                         xmulti_remove_handle(slot);
1188                         curl_easy_cleanup(slot->curl);
1189                 }
1190                 free(slot);
1191                 slot = next;
1192         }
1193         active_queue_head = NULL;
1194
1195 #ifndef NO_CURL_EASY_DUPHANDLE
1196         curl_easy_cleanup(curl_default);
1197 #endif
1198
1199 #ifdef USE_CURL_MULTI
1200         curl_multi_cleanup(curlm);
1201 #endif
1202         curl_global_cleanup();
1203
1204         string_list_clear(&extra_http_headers, 0);
1205
1206         curl_slist_free_all(pragma_header);
1207         pragma_header = NULL;
1208
1209         curl_slist_free_all(no_pragma_header);
1210         no_pragma_header = NULL;
1211
1212         if (curl_http_proxy) {
1213                 free((void *)curl_http_proxy);
1214                 curl_http_proxy = NULL;
1215         }
1216
1217         if (proxy_auth.password) {
1218                 memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1219                 FREE_AND_NULL(proxy_auth.password);
1220         }
1221
1222         free((void *)curl_proxyuserpwd);
1223         curl_proxyuserpwd = NULL;
1224
1225         free((void *)http_proxy_authmethod);
1226         http_proxy_authmethod = NULL;
1227
1228         if (cert_auth.password != NULL) {
1229                 memset(cert_auth.password, 0, strlen(cert_auth.password));
1230                 FREE_AND_NULL(cert_auth.password);
1231         }
1232         ssl_cert_password_required = 0;
1233
1234         FREE_AND_NULL(cached_accept_language);
1235 }
1236
1237 struct active_request_slot *get_active_slot(void)
1238 {
1239         struct active_request_slot *slot = active_queue_head;
1240         struct active_request_slot *newslot;
1241
1242 #ifdef USE_CURL_MULTI
1243         int num_transfers;
1244
1245         /* Wait for a slot to open up if the queue is full */
1246         while (active_requests >= max_requests) {
1247                 curl_multi_perform(curlm, &num_transfers);
1248                 if (num_transfers < active_requests)
1249                         process_curl_messages();
1250         }
1251 #endif
1252
1253         while (slot != NULL && slot->in_use)
1254                 slot = slot->next;
1255
1256         if (slot == NULL) {
1257                 newslot = xmalloc(sizeof(*newslot));
1258                 newslot->curl = NULL;
1259                 newslot->in_use = 0;
1260                 newslot->next = NULL;
1261
1262                 slot = active_queue_head;
1263                 if (slot == NULL) {
1264                         active_queue_head = newslot;
1265                 } else {
1266                         while (slot->next != NULL)
1267                                 slot = slot->next;
1268                         slot->next = newslot;
1269                 }
1270                 slot = newslot;
1271         }
1272
1273         if (slot->curl == NULL) {
1274 #ifdef NO_CURL_EASY_DUPHANDLE
1275                 slot->curl = get_curl_handle();
1276 #else
1277                 slot->curl = curl_easy_duphandle(curl_default);
1278 #endif
1279                 curl_session_count++;
1280         }
1281
1282         active_requests++;
1283         slot->in_use = 1;
1284         slot->results = NULL;
1285         slot->finished = NULL;
1286         slot->callback_data = NULL;
1287         slot->callback_func = NULL;
1288         curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1289         if (curl_save_cookies)
1290                 curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1291         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1292         curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1293         curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1294         curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1295         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1296         curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1297         curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1298         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1299         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1300         curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1301
1302         /*
1303          * Default following to off unless "ALWAYS" is configured; this gives
1304          * callers a sane starting point, and they can tweak for individual
1305          * HTTP_FOLLOW_* cases themselves.
1306          */
1307         if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1308                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1309         else
1310                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1311
1312 #if LIBCURL_VERSION_NUM >= 0x070a08
1313         curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1314 #endif
1315 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1316         curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1317 #endif
1318         if (http_auth.password || curl_empty_auth_enabled())
1319                 init_curl_http_auth(slot->curl);
1320
1321         return slot;
1322 }
1323
1324 int start_active_slot(struct active_request_slot *slot)
1325 {
1326 #ifdef USE_CURL_MULTI
1327         CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1328         int num_transfers;
1329
1330         if (curlm_result != CURLM_OK &&
1331             curlm_result != CURLM_CALL_MULTI_PERFORM) {
1332                 warning("curl_multi_add_handle failed: %s",
1333                         curl_multi_strerror(curlm_result));
1334                 active_requests--;
1335                 slot->in_use = 0;
1336                 return 0;
1337         }
1338
1339         /*
1340          * We know there must be something to do, since we just added
1341          * something.
1342          */
1343         curl_multi_perform(curlm, &num_transfers);
1344 #endif
1345         return 1;
1346 }
1347
1348 #ifdef USE_CURL_MULTI
1349 struct fill_chain {
1350         void *data;
1351         int (*fill)(void *);
1352         struct fill_chain *next;
1353 };
1354
1355 static struct fill_chain *fill_cfg;
1356
1357 void add_fill_function(void *data, int (*fill)(void *))
1358 {
1359         struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
1360         struct fill_chain **linkp = &fill_cfg;
1361         new_fill->data = data;
1362         new_fill->fill = fill;
1363         new_fill->next = NULL;
1364         while (*linkp)
1365                 linkp = &(*linkp)->next;
1366         *linkp = new_fill;
1367 }
1368
1369 void fill_active_slots(void)
1370 {
1371         struct active_request_slot *slot = active_queue_head;
1372
1373         while (active_requests < max_requests) {
1374                 struct fill_chain *fill;
1375                 for (fill = fill_cfg; fill; fill = fill->next)
1376                         if (fill->fill(fill->data))
1377                                 break;
1378
1379                 if (!fill)
1380                         break;
1381         }
1382
1383         while (slot != NULL) {
1384                 if (!slot->in_use && slot->curl != NULL
1385                         && curl_session_count > min_curl_sessions) {
1386                         curl_easy_cleanup(slot->curl);
1387                         slot->curl = NULL;
1388                         curl_session_count--;
1389                 }
1390                 slot = slot->next;
1391         }
1392 }
1393
1394 void step_active_slots(void)
1395 {
1396         int num_transfers;
1397         CURLMcode curlm_result;
1398
1399         do {
1400                 curlm_result = curl_multi_perform(curlm, &num_transfers);
1401         } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1402         if (num_transfers < active_requests) {
1403                 process_curl_messages();
1404                 fill_active_slots();
1405         }
1406 }
1407 #endif
1408
1409 void run_active_slot(struct active_request_slot *slot)
1410 {
1411 #ifdef USE_CURL_MULTI
1412         fd_set readfds;
1413         fd_set writefds;
1414         fd_set excfds;
1415         int max_fd;
1416         struct timeval select_timeout;
1417         int finished = 0;
1418
1419         slot->finished = &finished;
1420         while (!finished) {
1421                 step_active_slots();
1422
1423                 if (slot->in_use) {
1424 #if LIBCURL_VERSION_NUM >= 0x070f04
1425                         long curl_timeout;
1426                         curl_multi_timeout(curlm, &curl_timeout);
1427                         if (curl_timeout == 0) {
1428                                 continue;
1429                         } else if (curl_timeout == -1) {
1430                                 select_timeout.tv_sec  = 0;
1431                                 select_timeout.tv_usec = 50000;
1432                         } else {
1433                                 select_timeout.tv_sec  =  curl_timeout / 1000;
1434                                 select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1435                         }
1436 #else
1437                         select_timeout.tv_sec  = 0;
1438                         select_timeout.tv_usec = 50000;
1439 #endif
1440
1441                         max_fd = -1;
1442                         FD_ZERO(&readfds);
1443                         FD_ZERO(&writefds);
1444                         FD_ZERO(&excfds);
1445                         curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1446
1447                         /*
1448                          * It can happen that curl_multi_timeout returns a pathologically
1449                          * long timeout when curl_multi_fdset returns no file descriptors
1450                          * to read.  See commit message for more details.
1451                          */
1452                         if (max_fd < 0 &&
1453                             (select_timeout.tv_sec > 0 ||
1454                              select_timeout.tv_usec > 50000)) {
1455                                 select_timeout.tv_sec  = 0;
1456                                 select_timeout.tv_usec = 50000;
1457                         }
1458
1459                         select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1460                 }
1461         }
1462 #else
1463         while (slot->in_use) {
1464                 slot->curl_result = curl_easy_perform(slot->curl);
1465                 finish_active_slot(slot);
1466         }
1467 #endif
1468 }
1469
1470 static void release_active_slot(struct active_request_slot *slot)
1471 {
1472         closedown_active_slot(slot);
1473         if (slot->curl) {
1474                 xmulti_remove_handle(slot);
1475                 if (curl_session_count > min_curl_sessions) {
1476                         curl_easy_cleanup(slot->curl);
1477                         slot->curl = NULL;
1478                         curl_session_count--;
1479                 }
1480         }
1481 #ifdef USE_CURL_MULTI
1482         fill_active_slots();
1483 #endif
1484 }
1485
1486 void finish_all_active_slots(void)
1487 {
1488         struct active_request_slot *slot = active_queue_head;
1489
1490         while (slot != NULL)
1491                 if (slot->in_use) {
1492                         run_active_slot(slot);
1493                         slot = active_queue_head;
1494                 } else {
1495                         slot = slot->next;
1496                 }
1497 }
1498
1499 /* Helpers for modifying and creating URLs */
1500 static inline int needs_quote(int ch)
1501 {
1502         if (((ch >= 'A') && (ch <= 'Z'))
1503                         || ((ch >= 'a') && (ch <= 'z'))
1504                         || ((ch >= '0') && (ch <= '9'))
1505                         || (ch == '/')
1506                         || (ch == '-')
1507                         || (ch == '.'))
1508                 return 0;
1509         return 1;
1510 }
1511
1512 static char *quote_ref_url(const char *base, const char *ref)
1513 {
1514         struct strbuf buf = STRBUF_INIT;
1515         const char *cp;
1516         int ch;
1517
1518         end_url_with_slash(&buf, base);
1519
1520         for (cp = ref; (ch = *cp) != 0; cp++)
1521                 if (needs_quote(ch))
1522                         strbuf_addf(&buf, "%%%02x", ch);
1523                 else
1524                         strbuf_addch(&buf, *cp);
1525
1526         return strbuf_detach(&buf, NULL);
1527 }
1528
1529 void append_remote_object_url(struct strbuf *buf, const char *url,
1530                               const char *hex,
1531                               int only_two_digit_prefix)
1532 {
1533         end_url_with_slash(buf, url);
1534
1535         strbuf_addf(buf, "objects/%.*s/", 2, hex);
1536         if (!only_two_digit_prefix)
1537                 strbuf_addstr(buf, hex + 2);
1538 }
1539
1540 char *get_remote_object_url(const char *url, const char *hex,
1541                             int only_two_digit_prefix)
1542 {
1543         struct strbuf buf = STRBUF_INIT;
1544         append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1545         return strbuf_detach(&buf, NULL);
1546 }
1547
1548 void normalize_curl_result(CURLcode *result, long http_code,
1549                            char *errorstr, size_t errorlen)
1550 {
1551         /*
1552          * If we see a failing http code with CURLE_OK, we have turned off
1553          * FAILONERROR (to keep the server's custom error response), and should
1554          * translate the code into failure here.
1555          *
1556          * Likewise, if we see a redirect (30x code), that means we turned off
1557          * redirect-following, and we should treat the result as an error.
1558          */
1559         if (*result == CURLE_OK && http_code >= 300) {
1560                 *result = CURLE_HTTP_RETURNED_ERROR;
1561                 /*
1562                  * Normally curl will already have put the "reason phrase"
1563                  * from the server into curl_errorstr; unfortunately without
1564                  * FAILONERROR it is lost, so we can give only the numeric
1565                  * status code.
1566                  */
1567                 xsnprintf(errorstr, errorlen,
1568                           "The requested URL returned error: %ld",
1569                           http_code);
1570         }
1571 }
1572
1573 static int handle_curl_result(struct slot_results *results)
1574 {
1575         normalize_curl_result(&results->curl_result, results->http_code,
1576                               curl_errorstr, sizeof(curl_errorstr));
1577
1578         if (results->curl_result == CURLE_OK) {
1579                 credential_approve(&http_auth);
1580                 if (proxy_auth.password)
1581                         credential_approve(&proxy_auth);
1582                 return HTTP_OK;
1583         } else if (missing_target(results))
1584                 return HTTP_MISSING_TARGET;
1585         else if (results->http_code == 401) {
1586                 if (http_auth.username && http_auth.password) {
1587                         credential_reject(&http_auth);
1588                         return HTTP_NOAUTH;
1589                 } else {
1590 #ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1591                         http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1592                         if (results->auth_avail) {
1593                                 http_auth_methods &= results->auth_avail;
1594                                 http_auth_methods_restricted = 1;
1595                         }
1596 #endif
1597                         return HTTP_REAUTH;
1598                 }
1599         } else {
1600                 if (results->http_connectcode == 407)
1601                         credential_reject(&proxy_auth);
1602 #if LIBCURL_VERSION_NUM >= 0x070c00
1603                 if (!curl_errorstr[0])
1604                         strlcpy(curl_errorstr,
1605                                 curl_easy_strerror(results->curl_result),
1606                                 sizeof(curl_errorstr));
1607 #endif
1608                 return HTTP_ERROR;
1609         }
1610 }
1611
1612 int run_one_slot(struct active_request_slot *slot,
1613                  struct slot_results *results)
1614 {
1615         slot->results = results;
1616         if (!start_active_slot(slot)) {
1617                 xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1618                           "failed to start HTTP request");
1619                 return HTTP_START_FAILED;
1620         }
1621
1622         run_active_slot(slot);
1623         return handle_curl_result(results);
1624 }
1625
1626 struct curl_slist *http_copy_default_headers(void)
1627 {
1628         struct curl_slist *headers = NULL;
1629         const struct string_list_item *item;
1630
1631         for_each_string_list_item(item, &extra_http_headers)
1632                 headers = curl_slist_append(headers, item->string);
1633
1634         return headers;
1635 }
1636
1637 static CURLcode curlinfo_strbuf(CURL *curl, CURLINFO info, struct strbuf *buf)
1638 {
1639         char *ptr;
1640         CURLcode ret;
1641
1642         strbuf_reset(buf);
1643         ret = curl_easy_getinfo(curl, info, &ptr);
1644         if (!ret && ptr)
1645                 strbuf_addstr(buf, ptr);
1646         return ret;
1647 }
1648
1649 /*
1650  * Check for and extract a content-type parameter. "raw"
1651  * should be positioned at the start of the potential
1652  * parameter, with any whitespace already removed.
1653  *
1654  * "name" is the name of the parameter. The value is appended
1655  * to "out".
1656  */
1657 static int extract_param(const char *raw, const char *name,
1658                          struct strbuf *out)
1659 {
1660         size_t len = strlen(name);
1661
1662         if (strncasecmp(raw, name, len))
1663                 return -1;
1664         raw += len;
1665
1666         if (*raw != '=')
1667                 return -1;
1668         raw++;
1669
1670         while (*raw && !isspace(*raw) && *raw != ';')
1671                 strbuf_addch(out, *raw++);
1672         return 0;
1673 }
1674
1675 /*
1676  * Extract a normalized version of the content type, with any
1677  * spaces suppressed, all letters lowercased, and no trailing ";"
1678  * or parameters.
1679  *
1680  * Note that we will silently remove even invalid whitespace. For
1681  * example, "text / plain" is specifically forbidden by RFC 2616,
1682  * but "text/plain" is the only reasonable output, and this keeps
1683  * our code simple.
1684  *
1685  * If the "charset" argument is not NULL, store the value of any
1686  * charset parameter there.
1687  *
1688  * Example:
1689  *   "TEXT/PLAIN; charset=utf-8" -> "text/plain", "utf-8"
1690  *   "text / plain" -> "text/plain"
1691  */
1692 static void extract_content_type(struct strbuf *raw, struct strbuf *type,
1693                                  struct strbuf *charset)
1694 {
1695         const char *p;
1696
1697         strbuf_reset(type);
1698         strbuf_grow(type, raw->len);
1699         for (p = raw->buf; *p; p++) {
1700                 if (isspace(*p))
1701                         continue;
1702                 if (*p == ';') {
1703                         p++;
1704                         break;
1705                 }
1706                 strbuf_addch(type, tolower(*p));
1707         }
1708
1709         if (!charset)
1710                 return;
1711
1712         strbuf_reset(charset);
1713         while (*p) {
1714                 while (isspace(*p) || *p == ';')
1715                         p++;
1716                 if (!extract_param(p, "charset", charset))
1717                         return;
1718                 while (*p && !isspace(*p))
1719                         p++;
1720         }
1721
1722         if (!charset->len && starts_with(type->buf, "text/"))
1723                 strbuf_addstr(charset, "ISO-8859-1");
1724 }
1725
1726 static void write_accept_language(struct strbuf *buf)
1727 {
1728         /*
1729          * MAX_DECIMAL_PLACES must not be larger than 3. If it is larger than
1730          * that, q-value will be smaller than 0.001, the minimum q-value the
1731          * HTTP specification allows. See
1732          * http://tools.ietf.org/html/rfc7231#section-5.3.1 for q-value.
1733          */
1734         const int MAX_DECIMAL_PLACES = 3;
1735         const int MAX_LANGUAGE_TAGS = 1000;
1736         const int MAX_ACCEPT_LANGUAGE_HEADER_SIZE = 4000;
1737         char **language_tags = NULL;
1738         int num_langs = 0;
1739         const char *s = get_preferred_languages();
1740         int i;
1741         struct strbuf tag = STRBUF_INIT;
1742
1743         /* Don't add Accept-Language header if no language is preferred. */
1744         if (!s)
1745                 return;
1746
1747         /*
1748          * Split the colon-separated string of preferred languages into
1749          * language_tags array.
1750          */
1751         do {
1752                 /* collect language tag */
1753                 for (; *s && (isalnum(*s) || *s == '_'); s++)
1754                         strbuf_addch(&tag, *s == '_' ? '-' : *s);
1755
1756                 /* skip .codeset, @modifier and any other unnecessary parts */
1757                 while (*s && *s != ':')
1758                         s++;
1759
1760                 if (tag.len) {
1761                         num_langs++;
1762                         REALLOC_ARRAY(language_tags, num_langs);
1763                         language_tags[num_langs - 1] = strbuf_detach(&tag, NULL);
1764                         if (num_langs >= MAX_LANGUAGE_TAGS - 1) /* -1 for '*' */
1765                                 break;
1766                 }
1767         } while (*s++);
1768
1769         /* write Accept-Language header into buf */
1770         if (num_langs) {
1771                 int last_buf_len = 0;
1772                 int max_q;
1773                 int decimal_places;
1774                 char q_format[32];
1775
1776                 /* add '*' */
1777                 REALLOC_ARRAY(language_tags, num_langs + 1);
1778                 language_tags[num_langs++] = "*"; /* it's OK; this won't be freed */
1779
1780                 /* compute decimal_places */
1781                 for (max_q = 1, decimal_places = 0;
1782                      max_q < num_langs && decimal_places <= MAX_DECIMAL_PLACES;
1783                      decimal_places++, max_q *= 10)
1784                         ;
1785
1786                 xsnprintf(q_format, sizeof(q_format), ";q=0.%%0%dd", decimal_places);
1787
1788                 strbuf_addstr(buf, "Accept-Language: ");
1789
1790                 for (i = 0; i < num_langs; i++) {
1791                         if (i > 0)
1792                                 strbuf_addstr(buf, ", ");
1793
1794                         strbuf_addstr(buf, language_tags[i]);
1795
1796                         if (i > 0)
1797                                 strbuf_addf(buf, q_format, max_q - i);
1798
1799                         if (buf->len > MAX_ACCEPT_LANGUAGE_HEADER_SIZE) {
1800                                 strbuf_remove(buf, last_buf_len, buf->len - last_buf_len);
1801                                 break;
1802                         }
1803
1804                         last_buf_len = buf->len;
1805                 }
1806         }
1807
1808         /* free language tags -- last one is a static '*' */
1809         for (i = 0; i < num_langs - 1; i++)
1810                 free(language_tags[i]);
1811         free(language_tags);
1812 }
1813
1814 /*
1815  * Get an Accept-Language header which indicates user's preferred languages.
1816  *
1817  * Examples:
1818  *   LANGUAGE= -> ""
1819  *   LANGUAGE=ko:en -> "Accept-Language: ko, en; q=0.9, *; q=0.1"
1820  *   LANGUAGE=ko_KR.UTF-8:sr@latin -> "Accept-Language: ko-KR, sr; q=0.9, *; q=0.1"
1821  *   LANGUAGE=ko LANG=en_US.UTF-8 -> "Accept-Language: ko, *; q=0.1"
1822  *   LANGUAGE= LANG=en_US.UTF-8 -> "Accept-Language: en-US, *; q=0.1"
1823  *   LANGUAGE= LANG=C -> ""
1824  */
1825 static const char *get_accept_language(void)
1826 {
1827         if (!cached_accept_language) {
1828                 struct strbuf buf = STRBUF_INIT;
1829                 write_accept_language(&buf);
1830                 if (buf.len > 0)
1831                         cached_accept_language = strbuf_detach(&buf, NULL);
1832         }
1833
1834         return cached_accept_language;
1835 }
1836
1837 static void http_opt_request_remainder(CURL *curl, off_t pos)
1838 {
1839         char buf[128];
1840         xsnprintf(buf, sizeof(buf), "%"PRIuMAX"-", (uintmax_t)pos);
1841         curl_easy_setopt(curl, CURLOPT_RANGE, buf);
1842 }
1843
1844 /* http_request() targets */
1845 #define HTTP_REQUEST_STRBUF     0
1846 #define HTTP_REQUEST_FILE       1
1847
1848 static int http_request(const char *url,
1849                         void *result, int target,
1850                         const struct http_get_options *options)
1851 {
1852         struct active_request_slot *slot;
1853         struct slot_results results;
1854         struct curl_slist *headers = http_copy_default_headers();
1855         struct strbuf buf = STRBUF_INIT;
1856         const char *accept_language;
1857         int ret;
1858
1859         slot = get_active_slot();
1860         curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1861
1862         if (result == NULL) {
1863                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
1864         } else {
1865                 curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
1866                 curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
1867
1868                 if (target == HTTP_REQUEST_FILE) {
1869                         off_t posn = ftello(result);
1870                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1871                                          fwrite);
1872                         if (posn > 0)
1873                                 http_opt_request_remainder(slot->curl, posn);
1874                 } else
1875                         curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION,
1876                                          fwrite_buffer);
1877         }
1878
1879         accept_language = get_accept_language();
1880
1881         if (accept_language)
1882                 headers = curl_slist_append(headers, accept_language);
1883
1884         strbuf_addstr(&buf, "Pragma:");
1885         if (options && options->no_cache)
1886                 strbuf_addstr(&buf, " no-cache");
1887         if (options && options->initial_request &&
1888             http_follow_config == HTTP_FOLLOW_INITIAL)
1889                 curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1890
1891         headers = curl_slist_append(headers, buf.buf);
1892
1893         /* Add additional headers here */
1894         if (options && options->extra_headers) {
1895                 const struct string_list_item *item;
1896                 for_each_string_list_item(item, options->extra_headers) {
1897                         headers = curl_slist_append(headers, item->string);
1898                 }
1899         }
1900
1901         curl_easy_setopt(slot->curl, CURLOPT_URL, url);
1902         curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, headers);
1903         curl_easy_setopt(slot->curl, CURLOPT_ENCODING, "");
1904         curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
1905
1906         ret = run_one_slot(slot, &results);
1907
1908         if (options && options->content_type) {
1909                 struct strbuf raw = STRBUF_INIT;
1910                 curlinfo_strbuf(slot->curl, CURLINFO_CONTENT_TYPE, &raw);
1911                 extract_content_type(&raw, options->content_type,
1912                                      options->charset);
1913                 strbuf_release(&raw);
1914         }
1915
1916         if (options && options->effective_url)
1917                 curlinfo_strbuf(slot->curl, CURLINFO_EFFECTIVE_URL,
1918                                 options->effective_url);
1919
1920         curl_slist_free_all(headers);
1921         strbuf_release(&buf);
1922
1923         return ret;
1924 }
1925
1926 /*
1927  * Update the "base" url to a more appropriate value, as deduced by
1928  * redirects seen when requesting a URL starting with "url".
1929  *
1930  * The "asked" parameter is a URL that we asked curl to access, and must begin
1931  * with "base".
1932  *
1933  * The "got" parameter is the URL that curl reported to us as where we ended
1934  * up.
1935  *
1936  * Returns 1 if we updated the base url, 0 otherwise.
1937  *
1938  * Our basic strategy is to compare "base" and "asked" to find the bits
1939  * specific to our request. We then strip those bits off of "got" to yield the
1940  * new base. So for example, if our base is "http://example.com/foo.git",
1941  * and we ask for "http://example.com/foo.git/info/refs", we might end up
1942  * with "https://other.example.com/foo.git/info/refs". We would want the
1943  * new URL to become "https://other.example.com/foo.git".
1944  *
1945  * Note that this assumes a sane redirect scheme. It's entirely possible
1946  * in the example above to end up at a URL that does not even end in
1947  * "info/refs".  In such a case we die. There's not much we can do, such a
1948  * scheme is unlikely to represent a real git repository, and failing to
1949  * rewrite the base opens options for malicious redirects to do funny things.
1950  */
1951 static int update_url_from_redirect(struct strbuf *base,
1952                                     const char *asked,
1953                                     const struct strbuf *got)
1954 {
1955         const char *tail;
1956         size_t new_len;
1957
1958         if (!strcmp(asked, got->buf))
1959                 return 0;
1960
1961         if (!skip_prefix(asked, base->buf, &tail))
1962                 BUG("update_url_from_redirect: %s is not a superset of %s",
1963                     asked, base->buf);
1964
1965         new_len = got->len;
1966         if (!strip_suffix_mem(got->buf, &new_len, tail))
1967                 die(_("unable to update url base from redirection:\n"
1968                       "  asked for: %s\n"
1969                       "   redirect: %s"),
1970                     asked, got->buf);
1971
1972         strbuf_reset(base);
1973         strbuf_add(base, got->buf, new_len);
1974
1975         return 1;
1976 }
1977
1978 static int http_request_reauth(const char *url,
1979                                void *result, int target,
1980                                struct http_get_options *options)
1981 {
1982         int ret = http_request(url, result, target, options);
1983
1984         if (ret != HTTP_OK && ret != HTTP_REAUTH)
1985                 return ret;
1986
1987         if (options && options->effective_url && options->base_url) {
1988                 if (update_url_from_redirect(options->base_url,
1989                                              url, options->effective_url)) {
1990                         credential_from_url(&http_auth, options->base_url->buf);
1991                         url = options->effective_url->buf;
1992                 }
1993         }
1994
1995         if (ret != HTTP_REAUTH)
1996                 return ret;
1997
1998         /*
1999          * The previous request may have put cruft into our output stream; we
2000          * should clear it out before making our next request.
2001          */
2002         switch (target) {
2003         case HTTP_REQUEST_STRBUF:
2004                 strbuf_reset(result);
2005                 break;
2006         case HTTP_REQUEST_FILE:
2007                 if (fflush(result)) {
2008                         error_errno("unable to flush a file");
2009                         return HTTP_START_FAILED;
2010                 }
2011                 rewind(result);
2012                 if (ftruncate(fileno(result), 0) < 0) {
2013                         error_errno("unable to truncate a file");
2014                         return HTTP_START_FAILED;
2015                 }
2016                 break;
2017         default:
2018                 BUG("Unknown http_request target");
2019         }
2020
2021         credential_fill(&http_auth);
2022
2023         return http_request(url, result, target, options);
2024 }
2025
2026 int http_get_strbuf(const char *url,
2027                     struct strbuf *result,
2028                     struct http_get_options *options)
2029 {
2030         return http_request_reauth(url, result, HTTP_REQUEST_STRBUF, options);
2031 }
2032
2033 /*
2034  * Downloads a URL and stores the result in the given file.
2035  *
2036  * If a previous interrupted download is detected (i.e. a previous temporary
2037  * file is still around) the download is resumed.
2038  */
2039 static int http_get_file(const char *url, const char *filename,
2040                          struct http_get_options *options)
2041 {
2042         int ret;
2043         struct strbuf tmpfile = STRBUF_INIT;
2044         FILE *result;
2045
2046         strbuf_addf(&tmpfile, "%s.temp", filename);
2047         result = fopen(tmpfile.buf, "a");
2048         if (!result) {
2049                 error("Unable to open local file %s", tmpfile.buf);
2050                 ret = HTTP_ERROR;
2051                 goto cleanup;
2052         }
2053
2054         ret = http_request_reauth(url, result, HTTP_REQUEST_FILE, options);
2055         fclose(result);
2056
2057         if (ret == HTTP_OK && finalize_object_file(tmpfile.buf, filename))
2058                 ret = HTTP_ERROR;
2059 cleanup:
2060         strbuf_release(&tmpfile);
2061         return ret;
2062 }
2063
2064 int http_fetch_ref(const char *base, struct ref *ref)
2065 {
2066         struct http_get_options options = {0};
2067         char *url;
2068         struct strbuf buffer = STRBUF_INIT;
2069         int ret = -1;
2070
2071         options.no_cache = 1;
2072
2073         url = quote_ref_url(base, ref->name);
2074         if (http_get_strbuf(url, &buffer, &options) == HTTP_OK) {
2075                 strbuf_rtrim(&buffer);
2076                 if (buffer.len == the_hash_algo->hexsz)
2077                         ret = get_oid_hex(buffer.buf, &ref->old_oid);
2078                 else if (starts_with(buffer.buf, "ref: ")) {
2079                         ref->symref = xstrdup(buffer.buf + 5);
2080                         ret = 0;
2081                 }
2082         }
2083
2084         strbuf_release(&buffer);
2085         free(url);
2086         return ret;
2087 }
2088
2089 /* Helpers for fetching packs */
2090 static char *fetch_pack_index(unsigned char *hash, const char *base_url)
2091 {
2092         char *url, *tmp;
2093         struct strbuf buf = STRBUF_INIT;
2094
2095         if (http_is_verbose)
2096                 fprintf(stderr, "Getting index for pack %s\n", hash_to_hex(hash));
2097
2098         end_url_with_slash(&buf, base_url);
2099         strbuf_addf(&buf, "objects/pack/pack-%s.idx", hash_to_hex(hash));
2100         url = strbuf_detach(&buf, NULL);
2101
2102         strbuf_addf(&buf, "%s.temp", sha1_pack_index_name(hash));
2103         tmp = strbuf_detach(&buf, NULL);
2104
2105         if (http_get_file(url, tmp, NULL) != HTTP_OK) {
2106                 error("Unable to get pack index %s", url);
2107                 FREE_AND_NULL(tmp);
2108         }
2109
2110         free(url);
2111         return tmp;
2112 }
2113
2114 static int fetch_and_setup_pack_index(struct packed_git **packs_head,
2115         unsigned char *sha1, const char *base_url)
2116 {
2117         struct packed_git *new_pack;
2118         char *tmp_idx = NULL;
2119         int ret;
2120
2121         if (has_pack_index(sha1)) {
2122                 new_pack = parse_pack_index(sha1, sha1_pack_index_name(sha1));
2123                 if (!new_pack)
2124                         return -1; /* parse_pack_index() already issued error message */
2125                 goto add_pack;
2126         }
2127
2128         tmp_idx = fetch_pack_index(sha1, base_url);
2129         if (!tmp_idx)
2130                 return -1;
2131
2132         new_pack = parse_pack_index(sha1, tmp_idx);
2133         if (!new_pack) {
2134                 unlink(tmp_idx);
2135                 free(tmp_idx);
2136
2137                 return -1; /* parse_pack_index() already issued error message */
2138         }
2139
2140         ret = verify_pack_index(new_pack);
2141         if (!ret) {
2142                 close_pack_index(new_pack);
2143                 ret = finalize_object_file(tmp_idx, sha1_pack_index_name(sha1));
2144         }
2145         free(tmp_idx);
2146         if (ret)
2147                 return -1;
2148
2149 add_pack:
2150         new_pack->next = *packs_head;
2151         *packs_head = new_pack;
2152         return 0;
2153 }
2154
2155 int http_get_info_packs(const char *base_url, struct packed_git **packs_head)
2156 {
2157         struct http_get_options options = {0};
2158         int ret = 0;
2159         char *url;
2160         const char *data;
2161         struct strbuf buf = STRBUF_INIT;
2162         struct object_id oid;
2163
2164         end_url_with_slash(&buf, base_url);
2165         strbuf_addstr(&buf, "objects/info/packs");
2166         url = strbuf_detach(&buf, NULL);
2167
2168         options.no_cache = 1;
2169         ret = http_get_strbuf(url, &buf, &options);
2170         if (ret != HTTP_OK)
2171                 goto cleanup;
2172
2173         data = buf.buf;
2174         while (*data) {
2175                 if (skip_prefix(data, "P pack-", &data) &&
2176                     !parse_oid_hex(data, &oid, &data) &&
2177                     skip_prefix(data, ".pack", &data) &&
2178                     (*data == '\n' || *data == '\0')) {
2179                         fetch_and_setup_pack_index(packs_head, oid.hash, base_url);
2180                 } else {
2181                         data = strchrnul(data, '\n');
2182                 }
2183                 if (*data)
2184                         data++; /* skip past newline */
2185         }
2186
2187 cleanup:
2188         free(url);
2189         return ret;
2190 }
2191
2192 void release_http_pack_request(struct http_pack_request *preq)
2193 {
2194         if (preq->packfile != NULL) {
2195                 fclose(preq->packfile);
2196                 preq->packfile = NULL;
2197         }
2198         preq->slot = NULL;
2199         strbuf_release(&preq->tmpfile);
2200         free(preq->url);
2201         free(preq);
2202 }
2203
2204 int finish_http_pack_request(struct http_pack_request *preq)
2205 {
2206         struct packed_git **lst;
2207         struct packed_git *p = preq->target;
2208         char *tmp_idx;
2209         size_t len;
2210         struct child_process ip = CHILD_PROCESS_INIT;
2211
2212         close_pack_index(p);
2213
2214         fclose(preq->packfile);
2215         preq->packfile = NULL;
2216
2217         lst = preq->lst;
2218         while (*lst != p)
2219                 lst = &((*lst)->next);
2220         *lst = (*lst)->next;
2221
2222         if (!strip_suffix(preq->tmpfile.buf, ".pack.temp", &len))
2223                 BUG("pack tmpfile does not end in .pack.temp?");
2224         tmp_idx = xstrfmt("%.*s.idx.temp", (int)len, preq->tmpfile.buf);
2225
2226         argv_array_push(&ip.args, "index-pack");
2227         argv_array_pushl(&ip.args, "-o", tmp_idx, NULL);
2228         argv_array_push(&ip.args, preq->tmpfile.buf);
2229         ip.git_cmd = 1;
2230         ip.no_stdin = 1;
2231         ip.no_stdout = 1;
2232
2233         if (run_command(&ip)) {
2234                 unlink(preq->tmpfile.buf);
2235                 unlink(tmp_idx);
2236                 free(tmp_idx);
2237                 return -1;
2238         }
2239
2240         unlink(sha1_pack_index_name(p->hash));
2241
2242         if (finalize_object_file(preq->tmpfile.buf, sha1_pack_name(p->hash))
2243          || finalize_object_file(tmp_idx, sha1_pack_index_name(p->hash))) {
2244                 free(tmp_idx);
2245                 return -1;
2246         }
2247
2248         install_packed_git(the_repository, p);
2249         free(tmp_idx);
2250         return 0;
2251 }
2252
2253 struct http_pack_request *new_http_pack_request(
2254         struct packed_git *target, const char *base_url)
2255 {
2256         off_t prev_posn = 0;
2257         struct strbuf buf = STRBUF_INIT;
2258         struct http_pack_request *preq;
2259
2260         preq = xcalloc(1, sizeof(*preq));
2261         strbuf_init(&preq->tmpfile, 0);
2262         preq->target = target;
2263
2264         end_url_with_slash(&buf, base_url);
2265         strbuf_addf(&buf, "objects/pack/pack-%s.pack",
2266                 hash_to_hex(target->hash));
2267         preq->url = strbuf_detach(&buf, NULL);
2268
2269         strbuf_addf(&preq->tmpfile, "%s.temp", sha1_pack_name(target->hash));
2270         preq->packfile = fopen(preq->tmpfile.buf, "a");
2271         if (!preq->packfile) {
2272                 error("Unable to open local file %s for pack",
2273                       preq->tmpfile.buf);
2274                 goto abort;
2275         }
2276
2277         preq->slot = get_active_slot();
2278         curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
2279         curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
2280         curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
2281         curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
2282                 no_pragma_header);
2283
2284         /*
2285          * If there is data present from a previous transfer attempt,
2286          * resume where it left off
2287          */
2288         prev_posn = ftello(preq->packfile);
2289         if (prev_posn>0) {
2290                 if (http_is_verbose)
2291                         fprintf(stderr,
2292                                 "Resuming fetch of pack %s at byte %"PRIuMAX"\n",
2293                                 hash_to_hex(target->hash),
2294                                 (uintmax_t)prev_posn);
2295                 http_opt_request_remainder(preq->slot->curl, prev_posn);
2296         }
2297
2298         return preq;
2299
2300 abort:
2301         strbuf_release(&preq->tmpfile);
2302         free(preq->url);
2303         free(preq);
2304         return NULL;
2305 }
2306
2307 /* Helpers for fetching objects (loose) */
2308 static size_t fwrite_sha1_file(char *ptr, size_t eltsize, size_t nmemb,
2309                                void *data)
2310 {
2311         unsigned char expn[4096];
2312         size_t size = eltsize * nmemb;
2313         int posn = 0;
2314         struct http_object_request *freq = data;
2315         struct active_request_slot *slot = freq->slot;
2316
2317         if (slot) {
2318                 CURLcode c = curl_easy_getinfo(slot->curl, CURLINFO_HTTP_CODE,
2319                                                 &slot->http_code);
2320                 if (c != CURLE_OK)
2321                         BUG("curl_easy_getinfo for HTTP code failed: %s",
2322                                 curl_easy_strerror(c));
2323                 if (slot->http_code >= 300)
2324                         return nmemb;
2325         }
2326
2327         do {
2328                 ssize_t retval = xwrite(freq->localfile,
2329                                         (char *) ptr + posn, size - posn);
2330                 if (retval < 0)
2331                         return posn / eltsize;
2332                 posn += retval;
2333         } while (posn < size);
2334
2335         freq->stream.avail_in = size;
2336         freq->stream.next_in = (void *)ptr;
2337         do {
2338                 freq->stream.next_out = expn;
2339                 freq->stream.avail_out = sizeof(expn);
2340                 freq->zret = git_inflate(&freq->stream, Z_SYNC_FLUSH);
2341                 the_hash_algo->update_fn(&freq->c, expn,
2342                                          sizeof(expn) - freq->stream.avail_out);
2343         } while (freq->stream.avail_in && freq->zret == Z_OK);
2344         return nmemb;
2345 }
2346
2347 struct http_object_request *new_http_object_request(const char *base_url,
2348                                                     const struct object_id *oid)
2349 {
2350         char *hex = oid_to_hex(oid);
2351         struct strbuf filename = STRBUF_INIT;
2352         struct strbuf prevfile = STRBUF_INIT;
2353         int prevlocal;
2354         char prev_buf[PREV_BUF_SIZE];
2355         ssize_t prev_read = 0;
2356         off_t prev_posn = 0;
2357         struct http_object_request *freq;
2358
2359         freq = xcalloc(1, sizeof(*freq));
2360         strbuf_init(&freq->tmpfile, 0);
2361         oidcpy(&freq->oid, oid);
2362         freq->localfile = -1;
2363
2364         loose_object_path(the_repository, &filename, oid);
2365         strbuf_addf(&freq->tmpfile, "%s.temp", filename.buf);
2366
2367         strbuf_addf(&prevfile, "%s.prev", filename.buf);
2368         unlink_or_warn(prevfile.buf);
2369         rename(freq->tmpfile.buf, prevfile.buf);
2370         unlink_or_warn(freq->tmpfile.buf);
2371         strbuf_release(&filename);
2372
2373         if (freq->localfile != -1)
2374                 error("fd leakage in start: %d", freq->localfile);
2375         freq->localfile = open(freq->tmpfile.buf,
2376                                O_WRONLY | O_CREAT | O_EXCL, 0666);
2377         /*
2378          * This could have failed due to the "lazy directory creation";
2379          * try to mkdir the last path component.
2380          */
2381         if (freq->localfile < 0 && errno == ENOENT) {
2382                 char *dir = strrchr(freq->tmpfile.buf, '/');
2383                 if (dir) {
2384                         *dir = 0;
2385                         mkdir(freq->tmpfile.buf, 0777);
2386                         *dir = '/';
2387                 }
2388                 freq->localfile = open(freq->tmpfile.buf,
2389                                        O_WRONLY | O_CREAT | O_EXCL, 0666);
2390         }
2391
2392         if (freq->localfile < 0) {
2393                 error_errno("Couldn't create temporary file %s",
2394                             freq->tmpfile.buf);
2395                 goto abort;
2396         }
2397
2398         git_inflate_init(&freq->stream);
2399
2400         the_hash_algo->init_fn(&freq->c);
2401
2402         freq->url = get_remote_object_url(base_url, hex, 0);
2403
2404         /*
2405          * If a previous temp file is present, process what was already
2406          * fetched.
2407          */
2408         prevlocal = open(prevfile.buf, O_RDONLY);
2409         if (prevlocal != -1) {
2410                 do {
2411                         prev_read = xread(prevlocal, prev_buf, PREV_BUF_SIZE);
2412                         if (prev_read>0) {
2413                                 if (fwrite_sha1_file(prev_buf,
2414                                                      1,
2415                                                      prev_read,
2416                                                      freq) == prev_read) {
2417                                         prev_posn += prev_read;
2418                                 } else {
2419                                         prev_read = -1;
2420                                 }
2421                         }
2422                 } while (prev_read > 0);
2423                 close(prevlocal);
2424         }
2425         unlink_or_warn(prevfile.buf);
2426         strbuf_release(&prevfile);
2427
2428         /*
2429          * Reset inflate/SHA1 if there was an error reading the previous temp
2430          * file; also rewind to the beginning of the local file.
2431          */
2432         if (prev_read == -1) {
2433                 memset(&freq->stream, 0, sizeof(freq->stream));
2434                 git_inflate_init(&freq->stream);
2435                 the_hash_algo->init_fn(&freq->c);
2436                 if (prev_posn>0) {
2437                         prev_posn = 0;
2438                         lseek(freq->localfile, 0, SEEK_SET);
2439                         if (ftruncate(freq->localfile, 0) < 0) {
2440                                 error_errno("Couldn't truncate temporary file %s",
2441                                             freq->tmpfile.buf);
2442                                 goto abort;
2443                         }
2444                 }
2445         }
2446
2447         freq->slot = get_active_slot();
2448
2449         curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
2450         curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
2451         curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
2452         curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);
2453         curl_easy_setopt(freq->slot->curl, CURLOPT_URL, freq->url);
2454         curl_easy_setopt(freq->slot->curl, CURLOPT_HTTPHEADER, no_pragma_header);
2455
2456         /*
2457          * If we have successfully processed data from a previous fetch
2458          * attempt, only fetch the data we don't already have.
2459          */
2460         if (prev_posn>0) {
2461                 if (http_is_verbose)
2462                         fprintf(stderr,
2463                                 "Resuming fetch of object %s at byte %"PRIuMAX"\n",
2464                                 hex, (uintmax_t)prev_posn);
2465                 http_opt_request_remainder(freq->slot->curl, prev_posn);
2466         }
2467
2468         return freq;
2469
2470 abort:
2471         strbuf_release(&prevfile);
2472         free(freq->url);
2473         free(freq);
2474         return NULL;
2475 }
2476
2477 void process_http_object_request(struct http_object_request *freq)
2478 {
2479         if (freq->slot == NULL)
2480                 return;
2481         freq->curl_result = freq->slot->curl_result;
2482         freq->http_code = freq->slot->http_code;
2483         freq->slot = NULL;
2484 }
2485
2486 int finish_http_object_request(struct http_object_request *freq)
2487 {
2488         struct stat st;
2489         struct strbuf filename = STRBUF_INIT;
2490
2491         close(freq->localfile);
2492         freq->localfile = -1;
2493
2494         process_http_object_request(freq);
2495
2496         if (freq->http_code == 416) {
2497                 warning("requested range invalid; we may already have all the data.");
2498         } else if (freq->curl_result != CURLE_OK) {
2499                 if (stat(freq->tmpfile.buf, &st) == 0)
2500                         if (st.st_size == 0)
2501                                 unlink_or_warn(freq->tmpfile.buf);
2502                 return -1;
2503         }
2504
2505         git_inflate_end(&freq->stream);
2506         the_hash_algo->final_fn(freq->real_oid.hash, &freq->c);
2507         if (freq->zret != Z_STREAM_END) {
2508                 unlink_or_warn(freq->tmpfile.buf);
2509                 return -1;
2510         }
2511         if (!oideq(&freq->oid, &freq->real_oid)) {
2512                 unlink_or_warn(freq->tmpfile.buf);
2513                 return -1;
2514         }
2515         loose_object_path(the_repository, &filename, &freq->oid);
2516         freq->rename = finalize_object_file(freq->tmpfile.buf, filename.buf);
2517         strbuf_release(&filename);
2518
2519         return freq->rename;
2520 }
2521
2522 void abort_http_object_request(struct http_object_request *freq)
2523 {
2524         unlink_or_warn(freq->tmpfile.buf);
2525
2526         release_http_object_request(freq);
2527 }
2528
2529 void release_http_object_request(struct http_object_request *freq)
2530 {
2531         if (freq->localfile != -1) {
2532                 close(freq->localfile);
2533                 freq->localfile = -1;
2534         }
2535         FREE_AND_NULL(freq->url);
2536         if (freq->slot != NULL) {
2537                 freq->slot->callback_func = NULL;
2538                 freq->slot->callback_data = NULL;
2539                 release_active_slot(freq->slot);
2540                 freq->slot = NULL;
2541         }
2542         strbuf_release(&freq->tmpfile);
2543 }