http.con commit Merge branch 'bc/hash-independent-tests-part-5' (0281733)
   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
  19static struct trace_key trace_curl = TRACE_KEY_INIT(CURL);
  20static int trace_curl_data = 1;
  21static struct string_list cookies_to_redact = STRING_LIST_INIT_DUP;
  22#if LIBCURL_VERSION_NUM >= 0x070a08
  23long int git_curl_ipresolve = CURL_IPRESOLVE_WHATEVER;
  24#else
  25long int git_curl_ipresolve;
  26#endif
  27int active_requests;
  28int http_is_verbose;
  29ssize_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
  35static int min_curl_sessions = 1;
  36static int curl_session_count;
  37#ifdef USE_CURL_MULTI
  38static int max_requests = -1;
  39static CURLM *curlm;
  40#endif
  41#ifndef NO_CURL_EASY_DUPHANDLE
  42static CURL *curl_default;
  43#endif
  44
  45#define PREV_BUF_SIZE 4096
  46
  47char curl_errorstr[CURL_ERROR_SIZE];
  48
  49static int curl_ssl_verify = -1;
  50static int curl_ssl_try;
  51static const char *curl_http_version = NULL;
  52static const char *ssl_cert;
  53static const char *ssl_cipherlist;
  54static const char *ssl_version;
  55static 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
  72static const char *ssl_key;
  73#endif
  74#if LIBCURL_VERSION_NUM >= 0x070908
  75static const char *ssl_capath;
  76#endif
  77#if LIBCURL_VERSION_NUM >= 0x071304
  78static const char *curl_no_proxy;
  79#endif
  80#if LIBCURL_VERSION_NUM >= 0x072c00
  81static const char *ssl_pinnedkey;
  82#endif
  83static const char *ssl_cainfo;
  84static long curl_low_speed_limit = -1;
  85static long curl_low_speed_time = -1;
  86static int curl_ftp_no_epsv;
  87static const char *curl_http_proxy;
  88static const char *http_proxy_authmethod;
  89static 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
 107static const char *curl_deleg;
 108static 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
 118static struct credential proxy_auth = CREDENTIAL_INIT;
 119static const char *curl_proxyuserpwd;
 120static const char *curl_cookie_file;
 121static int curl_save_cookies;
 122struct credential http_auth = CREDENTIAL_INIT;
 123static int http_proactive_auth;
 124static const char *user_agent;
 125static int curl_empty_auth = -1;
 126
 127enum 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
 137static struct credential cert_auth = CREDENTIAL_INIT;
 138static int ssl_cert_password_required;
 139#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 140static unsigned long http_auth_methods = CURLAUTH_ANY;
 141static int http_auth_methods_restricted;
 142/* Modes for which empty_auth cannot actually help us. */
 143static 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
 151static struct curl_slist *pragma_header;
 152static struct curl_slist *no_pragma_header;
 153static struct curl_slist *extra_http_headers;
 154
 155static struct active_request_slot *active_queue_head;
 156
 157static char *cached_accept_language;
 158
 159static char *http_ssl_backend;
 160
 161static 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 */
 167static int http_schannel_use_ssl_cainfo;
 168
 169size_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
 183curlioerr 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
 201size_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
 210size_t fwrite_null(char *ptr, size_t eltsize, size_t nmemb, void *strbuf)
 211{
 212        return nmemb;
 213}
 214
 215static void closedown_active_slot(struct active_request_slot *slot)
 216{
 217        active_requests--;
 218        slot->in_use = 0;
 219}
 220
 221static 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
 249static 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
 257static 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
 286static int http_options(const char *var, const char *value, void *cb)
 287{
 288        if (!strcmp("http.version", var)) {
 289                return git_config_string(&curl_http_version, var, value);
 290        }
 291        if (!strcmp("http.sslverify", var)) {
 292                curl_ssl_verify = git_config_bool(var, value);
 293                return 0;
 294        }
 295        if (!strcmp("http.sslcipherlist", var))
 296                return git_config_string(&ssl_cipherlist, var, value);
 297        if (!strcmp("http.sslversion", var))
 298                return git_config_string(&ssl_version, var, value);
 299        if (!strcmp("http.sslcert", var))
 300                return git_config_pathname(&ssl_cert, var, value);
 301#if LIBCURL_VERSION_NUM >= 0x070903
 302        if (!strcmp("http.sslkey", var))
 303                return git_config_pathname(&ssl_key, var, value);
 304#endif
 305#if LIBCURL_VERSION_NUM >= 0x070908
 306        if (!strcmp("http.sslcapath", var))
 307                return git_config_pathname(&ssl_capath, var, value);
 308#endif
 309        if (!strcmp("http.sslcainfo", var))
 310                return git_config_pathname(&ssl_cainfo, var, value);
 311        if (!strcmp("http.sslcertpasswordprotected", var)) {
 312                ssl_cert_password_required = git_config_bool(var, value);
 313                return 0;
 314        }
 315        if (!strcmp("http.ssltry", var)) {
 316                curl_ssl_try = git_config_bool(var, value);
 317                return 0;
 318        }
 319        if (!strcmp("http.sslbackend", var)) {
 320                free(http_ssl_backend);
 321                http_ssl_backend = xstrdup_or_null(value);
 322                return 0;
 323        }
 324
 325        if (!strcmp("http.schannelcheckrevoke", var)) {
 326                http_schannel_check_revoke = git_config_bool(var, value);
 327                return 0;
 328        }
 329
 330        if (!strcmp("http.schannelusesslcainfo", var)) {
 331                http_schannel_use_ssl_cainfo = git_config_bool(var, value);
 332                return 0;
 333        }
 334
 335        if (!strcmp("http.minsessions", var)) {
 336                min_curl_sessions = git_config_int(var, value);
 337#ifndef USE_CURL_MULTI
 338                if (min_curl_sessions > 1)
 339                        min_curl_sessions = 1;
 340#endif
 341                return 0;
 342        }
 343#ifdef USE_CURL_MULTI
 344        if (!strcmp("http.maxrequests", var)) {
 345                max_requests = git_config_int(var, value);
 346                return 0;
 347        }
 348#endif
 349        if (!strcmp("http.lowspeedlimit", var)) {
 350                curl_low_speed_limit = (long)git_config_int(var, value);
 351                return 0;
 352        }
 353        if (!strcmp("http.lowspeedtime", var)) {
 354                curl_low_speed_time = (long)git_config_int(var, value);
 355                return 0;
 356        }
 357
 358        if (!strcmp("http.noepsv", var)) {
 359                curl_ftp_no_epsv = git_config_bool(var, value);
 360                return 0;
 361        }
 362        if (!strcmp("http.proxy", var))
 363                return git_config_string(&curl_http_proxy, var, value);
 364
 365        if (!strcmp("http.proxyauthmethod", var))
 366                return git_config_string(&http_proxy_authmethod, var, value);
 367
 368        if (!strcmp("http.cookiefile", var))
 369                return git_config_pathname(&curl_cookie_file, var, value);
 370        if (!strcmp("http.savecookies", var)) {
 371                curl_save_cookies = git_config_bool(var, value);
 372                return 0;
 373        }
 374
 375        if (!strcmp("http.postbuffer", var)) {
 376                http_post_buffer = git_config_ssize_t(var, value);
 377                if (http_post_buffer < 0)
 378                        warning(_("negative value for http.postbuffer; defaulting to %d"), LARGE_PACKET_MAX);
 379                if (http_post_buffer < LARGE_PACKET_MAX)
 380                        http_post_buffer = LARGE_PACKET_MAX;
 381                return 0;
 382        }
 383
 384        if (!strcmp("http.useragent", var))
 385                return git_config_string(&user_agent, var, value);
 386
 387        if (!strcmp("http.emptyauth", var)) {
 388                if (value && !strcmp("auto", value))
 389                        curl_empty_auth = -1;
 390                else
 391                        curl_empty_auth = git_config_bool(var, value);
 392                return 0;
 393        }
 394
 395        if (!strcmp("http.delegation", var)) {
 396#ifdef CURLGSSAPI_DELEGATION_FLAG
 397                return git_config_string(&curl_deleg, var, value);
 398#else
 399                warning(_("Delegation control is not supported with cURL < 7.22.0"));
 400                return 0;
 401#endif
 402        }
 403
 404        if (!strcmp("http.pinnedpubkey", var)) {
 405#if LIBCURL_VERSION_NUM >= 0x072c00
 406                return git_config_pathname(&ssl_pinnedkey, var, value);
 407#else
 408                warning(_("Public key pinning not supported with cURL < 7.44.0"));
 409                return 0;
 410#endif
 411        }
 412
 413        if (!strcmp("http.extraheader", var)) {
 414                if (!value) {
 415                        return config_error_nonbool(var);
 416                } else if (!*value) {
 417                        curl_slist_free_all(extra_http_headers);
 418                        extra_http_headers = NULL;
 419                } else {
 420                        extra_http_headers =
 421                                curl_slist_append(extra_http_headers, value);
 422                }
 423                return 0;
 424        }
 425
 426        if (!strcmp("http.followredirects", var)) {
 427                if (value && !strcmp(value, "initial"))
 428                        http_follow_config = HTTP_FOLLOW_INITIAL;
 429                else if (git_config_bool(var, value))
 430                        http_follow_config = HTTP_FOLLOW_ALWAYS;
 431                else
 432                        http_follow_config = HTTP_FOLLOW_NONE;
 433                return 0;
 434        }
 435
 436        /* Fall back on the default ones */
 437        return git_default_config(var, value, cb);
 438}
 439
 440static int curl_empty_auth_enabled(void)
 441{
 442        if (curl_empty_auth >= 0)
 443                return curl_empty_auth;
 444
 445#ifndef LIBCURL_CAN_HANDLE_AUTH_ANY
 446        /*
 447         * Our libcurl is too old to do AUTH_ANY in the first place;
 448         * just default to turning the feature off.
 449         */
 450#else
 451        /*
 452         * In the automatic case, kick in the empty-auth
 453         * hack as long as we would potentially try some
 454         * method more exotic than "Basic" or "Digest".
 455         *
 456         * But only do this when this is our second or
 457         * subsequent request, as by then we know what
 458         * methods are available.
 459         */
 460        if (http_auth_methods_restricted &&
 461            (http_auth_methods & ~empty_auth_useless))
 462                return 1;
 463#endif
 464        return 0;
 465}
 466
 467static void init_curl_http_auth(CURL *result)
 468{
 469        if (!http_auth.username || !*http_auth.username) {
 470                if (curl_empty_auth_enabled())
 471                        curl_easy_setopt(result, CURLOPT_USERPWD, ":");
 472                return;
 473        }
 474
 475        credential_fill(&http_auth);
 476
 477#if LIBCURL_VERSION_NUM >= 0x071301
 478        curl_easy_setopt(result, CURLOPT_USERNAME, http_auth.username);
 479        curl_easy_setopt(result, CURLOPT_PASSWORD, http_auth.password);
 480#else
 481        {
 482                static struct strbuf up = STRBUF_INIT;
 483                /*
 484                 * Note that we assume we only ever have a single set of
 485                 * credentials in a given program run, so we do not have
 486                 * to worry about updating this buffer, only setting its
 487                 * initial value.
 488                 */
 489                if (!up.len)
 490                        strbuf_addf(&up, "%s:%s",
 491                                http_auth.username, http_auth.password);
 492                curl_easy_setopt(result, CURLOPT_USERPWD, up.buf);
 493        }
 494#endif
 495}
 496
 497/* *var must be free-able */
 498static void var_override(const char **var, char *value)
 499{
 500        if (value) {
 501                free((void *)*var);
 502                *var = xstrdup(value);
 503        }
 504}
 505
 506static void set_proxyauth_name_password(CURL *result)
 507{
 508#if LIBCURL_VERSION_NUM >= 0x071301
 509                curl_easy_setopt(result, CURLOPT_PROXYUSERNAME,
 510                        proxy_auth.username);
 511                curl_easy_setopt(result, CURLOPT_PROXYPASSWORD,
 512                        proxy_auth.password);
 513#else
 514                struct strbuf s = STRBUF_INIT;
 515
 516                strbuf_addstr_urlencode(&s, proxy_auth.username,
 517                                        is_rfc3986_unreserved);
 518                strbuf_addch(&s, ':');
 519                strbuf_addstr_urlencode(&s, proxy_auth.password,
 520                                        is_rfc3986_unreserved);
 521                curl_proxyuserpwd = strbuf_detach(&s, NULL);
 522                curl_easy_setopt(result, CURLOPT_PROXYUSERPWD, curl_proxyuserpwd);
 523#endif
 524}
 525
 526static void init_curl_proxy_auth(CURL *result)
 527{
 528        if (proxy_auth.username) {
 529                if (!proxy_auth.password)
 530                        credential_fill(&proxy_auth);
 531                set_proxyauth_name_password(result);
 532        }
 533
 534        var_override(&http_proxy_authmethod, getenv("GIT_HTTP_PROXY_AUTHMETHOD"));
 535
 536#if LIBCURL_VERSION_NUM >= 0x070a07 /* CURLOPT_PROXYAUTH and CURLAUTH_ANY */
 537        if (http_proxy_authmethod) {
 538                int i;
 539                for (i = 0; i < ARRAY_SIZE(proxy_authmethods); i++) {
 540                        if (!strcmp(http_proxy_authmethod, proxy_authmethods[i].name)) {
 541                                curl_easy_setopt(result, CURLOPT_PROXYAUTH,
 542                                                proxy_authmethods[i].curlauth_param);
 543                                break;
 544                        }
 545                }
 546                if (i == ARRAY_SIZE(proxy_authmethods)) {
 547                        warning("unsupported proxy authentication method %s: using anyauth",
 548                                        http_proxy_authmethod);
 549                        curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 550                }
 551        }
 552        else
 553                curl_easy_setopt(result, CURLOPT_PROXYAUTH, CURLAUTH_ANY);
 554#endif
 555}
 556
 557static int has_cert_password(void)
 558{
 559        if (ssl_cert == NULL || ssl_cert_password_required != 1)
 560                return 0;
 561        if (!cert_auth.password) {
 562                cert_auth.protocol = xstrdup("cert");
 563                cert_auth.username = xstrdup("");
 564                cert_auth.path = xstrdup(ssl_cert);
 565                credential_fill(&cert_auth);
 566        }
 567        return 1;
 568}
 569
 570#if LIBCURL_VERSION_NUM >= 0x071900
 571static void set_curl_keepalive(CURL *c)
 572{
 573        curl_easy_setopt(c, CURLOPT_TCP_KEEPALIVE, 1);
 574}
 575
 576#elif LIBCURL_VERSION_NUM >= 0x071000
 577static int sockopt_callback(void *client, curl_socket_t fd, curlsocktype type)
 578{
 579        int ka = 1;
 580        int rc;
 581        socklen_t len = (socklen_t)sizeof(ka);
 582
 583        if (type != CURLSOCKTYPE_IPCXN)
 584                return 0;
 585
 586        rc = setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, (void *)&ka, len);
 587        if (rc < 0)
 588                warning_errno("unable to set SO_KEEPALIVE on socket");
 589
 590        return 0; /* CURL_SOCKOPT_OK only exists since curl 7.21.5 */
 591}
 592
 593static void set_curl_keepalive(CURL *c)
 594{
 595        curl_easy_setopt(c, CURLOPT_SOCKOPTFUNCTION, sockopt_callback);
 596}
 597
 598#else
 599static void set_curl_keepalive(CURL *c)
 600{
 601        /* not supported on older curl versions */
 602}
 603#endif
 604
 605static void redact_sensitive_header(struct strbuf *header)
 606{
 607        const char *sensitive_header;
 608
 609        if (skip_prefix(header->buf, "Authorization:", &sensitive_header) ||
 610            skip_prefix(header->buf, "Proxy-Authorization:", &sensitive_header)) {
 611                /* The first token is the type, which is OK to log */
 612                while (isspace(*sensitive_header))
 613                        sensitive_header++;
 614                while (*sensitive_header && !isspace(*sensitive_header))
 615                        sensitive_header++;
 616                /* Everything else is opaque and possibly sensitive */
 617                strbuf_setlen(header,  sensitive_header - header->buf);
 618                strbuf_addstr(header, " <redacted>");
 619        } else if (cookies_to_redact.nr &&
 620                   skip_prefix(header->buf, "Cookie:", &sensitive_header)) {
 621                struct strbuf redacted_header = STRBUF_INIT;
 622                char *cookie;
 623
 624                while (isspace(*sensitive_header))
 625                        sensitive_header++;
 626
 627                /*
 628                 * The contents of header starting from sensitive_header will
 629                 * subsequently be overridden, so it is fine to mutate this
 630                 * string (hence the assignment to "char *").
 631                 */
 632                cookie = (char *) sensitive_header;
 633
 634                while (cookie) {
 635                        char *equals;
 636                        char *semicolon = strstr(cookie, "; ");
 637                        if (semicolon)
 638                                *semicolon = 0;
 639                        equals = strchrnul(cookie, '=');
 640                        if (!equals) {
 641                                /* invalid cookie, just append and continue */
 642                                strbuf_addstr(&redacted_header, cookie);
 643                                continue;
 644                        }
 645                        *equals = 0; /* temporarily set to NUL for lookup */
 646                        if (string_list_lookup(&cookies_to_redact, cookie)) {
 647                                strbuf_addstr(&redacted_header, cookie);
 648                                strbuf_addstr(&redacted_header, "=<redacted>");
 649                        } else {
 650                                *equals = '=';
 651                                strbuf_addstr(&redacted_header, cookie);
 652                        }
 653                        if (semicolon) {
 654                                /*
 655                                 * There are more cookies. (Or, for some
 656                                 * reason, the input string ends in "; ".)
 657                                 */
 658                                strbuf_addstr(&redacted_header, "; ");
 659                                cookie = semicolon + strlen("; ");
 660                        } else {
 661                                cookie = NULL;
 662                        }
 663                }
 664
 665                strbuf_setlen(header, sensitive_header - header->buf);
 666                strbuf_addbuf(header, &redacted_header);
 667        }
 668}
 669
 670static void curl_dump_header(const char *text, unsigned char *ptr, size_t size, int hide_sensitive_header)
 671{
 672        struct strbuf out = STRBUF_INIT;
 673        struct strbuf **headers, **header;
 674
 675        strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 676                text, (long)size, (long)size);
 677        trace_strbuf(&trace_curl, &out);
 678        strbuf_reset(&out);
 679        strbuf_add(&out, ptr, size);
 680        headers = strbuf_split_max(&out, '\n', 0);
 681
 682        for (header = headers; *header; header++) {
 683                if (hide_sensitive_header)
 684                        redact_sensitive_header(*header);
 685                strbuf_insert((*header), 0, text, strlen(text));
 686                strbuf_insert((*header), strlen(text), ": ", 2);
 687                strbuf_rtrim((*header));
 688                strbuf_addch((*header), '\n');
 689                trace_strbuf(&trace_curl, (*header));
 690        }
 691        strbuf_list_free(headers);
 692        strbuf_release(&out);
 693}
 694
 695static void curl_dump_data(const char *text, unsigned char *ptr, size_t size)
 696{
 697        size_t i;
 698        struct strbuf out = STRBUF_INIT;
 699        unsigned int width = 60;
 700
 701        strbuf_addf(&out, "%s, %10.10ld bytes (0x%8.8lx)\n",
 702                text, (long)size, (long)size);
 703        trace_strbuf(&trace_curl, &out);
 704
 705        for (i = 0; i < size; i += width) {
 706                size_t w;
 707
 708                strbuf_reset(&out);
 709                strbuf_addf(&out, "%s: ", text);
 710                for (w = 0; (w < width) && (i + w < size); w++) {
 711                        unsigned char ch = ptr[i + w];
 712
 713                        strbuf_addch(&out,
 714                                       (ch >= 0x20) && (ch < 0x80)
 715                                       ? ch : '.');
 716                }
 717                strbuf_addch(&out, '\n');
 718                trace_strbuf(&trace_curl, &out);
 719        }
 720        strbuf_release(&out);
 721}
 722
 723static int curl_trace(CURL *handle, curl_infotype type, char *data, size_t size, void *userp)
 724{
 725        const char *text;
 726        enum { NO_FILTER = 0, DO_FILTER = 1 };
 727
 728        switch (type) {
 729        case CURLINFO_TEXT:
 730                trace_printf_key(&trace_curl, "== Info: %s", data);
 731                break;
 732        case CURLINFO_HEADER_OUT:
 733                text = "=> Send header";
 734                curl_dump_header(text, (unsigned char *)data, size, DO_FILTER);
 735                break;
 736        case CURLINFO_DATA_OUT:
 737                if (trace_curl_data) {
 738                        text = "=> Send data";
 739                        curl_dump_data(text, (unsigned char *)data, size);
 740                }
 741                break;
 742        case CURLINFO_SSL_DATA_OUT:
 743                if (trace_curl_data) {
 744                        text = "=> Send SSL data";
 745                        curl_dump_data(text, (unsigned char *)data, size);
 746                }
 747                break;
 748        case CURLINFO_HEADER_IN:
 749                text = "<= Recv header";
 750                curl_dump_header(text, (unsigned char *)data, size, NO_FILTER);
 751                break;
 752        case CURLINFO_DATA_IN:
 753                if (trace_curl_data) {
 754                        text = "<= Recv data";
 755                        curl_dump_data(text, (unsigned char *)data, size);
 756                }
 757                break;
 758        case CURLINFO_SSL_DATA_IN:
 759                if (trace_curl_data) {
 760                        text = "<= Recv SSL data";
 761                        curl_dump_data(text, (unsigned char *)data, size);
 762                }
 763                break;
 764
 765        default:                /* we ignore unknown types by default */
 766                return 0;
 767        }
 768        return 0;
 769}
 770
 771void setup_curl_trace(CURL *handle)
 772{
 773        if (!trace_want(&trace_curl))
 774                return;
 775        curl_easy_setopt(handle, CURLOPT_VERBOSE, 1L);
 776        curl_easy_setopt(handle, CURLOPT_DEBUGFUNCTION, curl_trace);
 777        curl_easy_setopt(handle, CURLOPT_DEBUGDATA, NULL);
 778}
 779
 780#ifdef CURLPROTO_HTTP
 781static long get_curl_allowed_protocols(int from_user)
 782{
 783        long allowed_protocols = 0;
 784
 785        if (is_transport_allowed("http", from_user))
 786                allowed_protocols |= CURLPROTO_HTTP;
 787        if (is_transport_allowed("https", from_user))
 788                allowed_protocols |= CURLPROTO_HTTPS;
 789        if (is_transport_allowed("ftp", from_user))
 790                allowed_protocols |= CURLPROTO_FTP;
 791        if (is_transport_allowed("ftps", from_user))
 792                allowed_protocols |= CURLPROTO_FTPS;
 793
 794        return allowed_protocols;
 795}
 796#endif
 797
 798#if LIBCURL_VERSION_NUM >=0x072f00
 799static int get_curl_http_version_opt(const char *version_string, long *opt)
 800{
 801        int i;
 802        static struct {
 803                const char *name;
 804                long opt_token;
 805        } choice[] = {
 806                { "HTTP/1.1", CURL_HTTP_VERSION_1_1 },
 807                { "HTTP/2", CURL_HTTP_VERSION_2 }
 808        };
 809
 810        for (i = 0; i < ARRAY_SIZE(choice); i++) {
 811                if (!strcmp(version_string, choice[i].name)) {
 812                        *opt = choice[i].opt_token;
 813                        return 0;
 814                }
 815        }
 816
 817        warning("unknown value given to http.version: '%s'", version_string);
 818        return -1; /* not found */
 819}
 820
 821#endif
 822
 823static CURL *get_curl_handle(void)
 824{
 825        CURL *result = curl_easy_init();
 826
 827        if (!result)
 828                die("curl_easy_init failed");
 829
 830        if (!curl_ssl_verify) {
 831                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 0);
 832                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 0);
 833        } else {
 834                /* Verify authenticity of the peer's certificate */
 835                curl_easy_setopt(result, CURLOPT_SSL_VERIFYPEER, 1);
 836                /* The name in the cert must match whom we tried to connect */
 837                curl_easy_setopt(result, CURLOPT_SSL_VERIFYHOST, 2);
 838        }
 839
 840#if LIBCURL_VERSION_NUM >= 0x072f00 // 7.47.0
 841    if (curl_http_version) {
 842                long opt;
 843                if (!get_curl_http_version_opt(curl_http_version, &opt)) {
 844                        /* Set request use http version */
 845                        curl_easy_setopt(result, CURLOPT_HTTP_VERSION, opt);
 846                }
 847    }
 848#endif
 849
 850#if LIBCURL_VERSION_NUM >= 0x070907
 851        curl_easy_setopt(result, CURLOPT_NETRC, CURL_NETRC_OPTIONAL);
 852#endif
 853#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
 854        curl_easy_setopt(result, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 855#endif
 856
 857#ifdef CURLGSSAPI_DELEGATION_FLAG
 858        if (curl_deleg) {
 859                int i;
 860                for (i = 0; i < ARRAY_SIZE(curl_deleg_levels); i++) {
 861                        if (!strcmp(curl_deleg, curl_deleg_levels[i].name)) {
 862                                curl_easy_setopt(result, CURLOPT_GSSAPI_DELEGATION,
 863                                                curl_deleg_levels[i].curl_deleg_param);
 864                                break;
 865                        }
 866                }
 867                if (i == ARRAY_SIZE(curl_deleg_levels))
 868                        warning("Unknown delegation method '%s': using default",
 869                                curl_deleg);
 870        }
 871#endif
 872
 873        if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 874            !http_schannel_check_revoke) {
 875#if LIBCURL_VERSION_NUM >= 0x072c00
 876                curl_easy_setopt(result, CURLOPT_SSL_OPTIONS, CURLSSLOPT_NO_REVOKE);
 877#else
 878                warning(_("CURLSSLOPT_NO_REVOKE not supported with cURL < 7.44.0"));
 879#endif
 880        }
 881
 882        if (http_proactive_auth)
 883                init_curl_http_auth(result);
 884
 885        if (getenv("GIT_SSL_VERSION"))
 886                ssl_version = getenv("GIT_SSL_VERSION");
 887        if (ssl_version && *ssl_version) {
 888                int i;
 889                for (i = 0; i < ARRAY_SIZE(sslversions); i++) {
 890                        if (!strcmp(ssl_version, sslversions[i].name)) {
 891                                curl_easy_setopt(result, CURLOPT_SSLVERSION,
 892                                                 sslversions[i].ssl_version);
 893                                break;
 894                        }
 895                }
 896                if (i == ARRAY_SIZE(sslversions))
 897                        warning("unsupported ssl version %s: using default",
 898                                ssl_version);
 899        }
 900
 901        if (getenv("GIT_SSL_CIPHER_LIST"))
 902                ssl_cipherlist = getenv("GIT_SSL_CIPHER_LIST");
 903        if (ssl_cipherlist != NULL && *ssl_cipherlist)
 904                curl_easy_setopt(result, CURLOPT_SSL_CIPHER_LIST,
 905                                ssl_cipherlist);
 906
 907        if (ssl_cert != NULL)
 908                curl_easy_setopt(result, CURLOPT_SSLCERT, ssl_cert);
 909        if (has_cert_password())
 910                curl_easy_setopt(result, CURLOPT_KEYPASSWD, cert_auth.password);
 911#if LIBCURL_VERSION_NUM >= 0x070903
 912        if (ssl_key != NULL)
 913                curl_easy_setopt(result, CURLOPT_SSLKEY, ssl_key);
 914#endif
 915#if LIBCURL_VERSION_NUM >= 0x070908
 916        if (ssl_capath != NULL)
 917                curl_easy_setopt(result, CURLOPT_CAPATH, ssl_capath);
 918#endif
 919#if LIBCURL_VERSION_NUM >= 0x072c00
 920        if (ssl_pinnedkey != NULL)
 921                curl_easy_setopt(result, CURLOPT_PINNEDPUBLICKEY, ssl_pinnedkey);
 922#endif
 923        if (http_ssl_backend && !strcmp("schannel", http_ssl_backend) &&
 924            !http_schannel_use_ssl_cainfo) {
 925                curl_easy_setopt(result, CURLOPT_CAINFO, NULL);
 926#if LIBCURL_VERSION_NUM >= 0x073400
 927                curl_easy_setopt(result, CURLOPT_PROXY_CAINFO, NULL);
 928#endif
 929        } else if (ssl_cainfo != NULL)
 930                curl_easy_setopt(result, CURLOPT_CAINFO, ssl_cainfo);
 931
 932        if (curl_low_speed_limit > 0 && curl_low_speed_time > 0) {
 933                curl_easy_setopt(result, CURLOPT_LOW_SPEED_LIMIT,
 934                                 curl_low_speed_limit);
 935                curl_easy_setopt(result, CURLOPT_LOW_SPEED_TIME,
 936                                 curl_low_speed_time);
 937        }
 938
 939        curl_easy_setopt(result, CURLOPT_MAXREDIRS, 20);
 940#if LIBCURL_VERSION_NUM >= 0x071301
 941        curl_easy_setopt(result, CURLOPT_POSTREDIR, CURL_REDIR_POST_ALL);
 942#elif LIBCURL_VERSION_NUM >= 0x071101
 943        curl_easy_setopt(result, CURLOPT_POST301, 1);
 944#endif
 945#ifdef CURLPROTO_HTTP
 946        curl_easy_setopt(result, CURLOPT_REDIR_PROTOCOLS,
 947                         get_curl_allowed_protocols(0));
 948        curl_easy_setopt(result, CURLOPT_PROTOCOLS,
 949                         get_curl_allowed_protocols(-1));
 950#else
 951        warning(_("Protocol restrictions not supported with cURL < 7.19.4"));
 952#endif
 953        if (getenv("GIT_CURL_VERBOSE"))
 954                curl_easy_setopt(result, CURLOPT_VERBOSE, 1L);
 955        setup_curl_trace(result);
 956        if (getenv("GIT_TRACE_CURL_NO_DATA"))
 957                trace_curl_data = 0;
 958        if (getenv("GIT_REDACT_COOKIES")) {
 959                string_list_split(&cookies_to_redact,
 960                                  getenv("GIT_REDACT_COOKIES"), ',', -1);
 961                string_list_sort(&cookies_to_redact);
 962        }
 963
 964        curl_easy_setopt(result, CURLOPT_USERAGENT,
 965                user_agent ? user_agent : git_user_agent());
 966
 967        if (curl_ftp_no_epsv)
 968                curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);
 969
 970#ifdef CURLOPT_USE_SSL
 971        if (curl_ssl_try)
 972                curl_easy_setopt(result, CURLOPT_USE_SSL, CURLUSESSL_TRY);
 973#endif
 974
 975        /*
 976         * CURL also examines these variables as a fallback; but we need to query
 977         * them here in order to decide whether to prompt for missing password (cf.
 978         * init_curl_proxy_auth()).
 979         *
 980         * Unlike many other common environment variables, these are historically
 981         * lowercase only. It appears that CURL did not know this and implemented
 982         * only uppercase variants, which was later corrected to take both - with
 983         * the exception of http_proxy, which is lowercase only also in CURL. As
 984         * the lowercase versions are the historical quasi-standard, they take
 985         * precedence here, as in CURL.
 986         */
 987        if (!curl_http_proxy) {
 988                if (http_auth.protocol && !strcmp(http_auth.protocol, "https")) {
 989                        var_override(&curl_http_proxy, getenv("HTTPS_PROXY"));
 990                        var_override(&curl_http_proxy, getenv("https_proxy"));
 991                } else {
 992                        var_override(&curl_http_proxy, getenv("http_proxy"));
 993                }
 994                if (!curl_http_proxy) {
 995                        var_override(&curl_http_proxy, getenv("ALL_PROXY"));
 996                        var_override(&curl_http_proxy, getenv("all_proxy"));
 997                }
 998        }
 999
1000        if (curl_http_proxy && curl_http_proxy[0] == '\0') {
1001                /*
1002                 * Handle case with the empty http.proxy value here to keep
1003                 * common code clean.
1004                 * NB: empty option disables proxying at all.
1005                 */
1006                curl_easy_setopt(result, CURLOPT_PROXY, "");
1007        } else if (curl_http_proxy) {
1008#if LIBCURL_VERSION_NUM >= 0x071800
1009                if (starts_with(curl_http_proxy, "socks5h"))
1010                        curl_easy_setopt(result,
1011                                CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
1012                else if (starts_with(curl_http_proxy, "socks5"))
1013                        curl_easy_setopt(result,
1014                                CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
1015                else if (starts_with(curl_http_proxy, "socks4a"))
1016                        curl_easy_setopt(result,
1017                                CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4A);
1018                else if (starts_with(curl_http_proxy, "socks"))
1019                        curl_easy_setopt(result,
1020                                CURLOPT_PROXYTYPE, CURLPROXY_SOCKS4);
1021#endif
1022#if LIBCURL_VERSION_NUM >= 0x073400
1023                else if (starts_with(curl_http_proxy, "https"))
1024                        curl_easy_setopt(result,
1025                                CURLOPT_PROXYTYPE, CURLPROXY_HTTPS);
1026#endif
1027                if (strstr(curl_http_proxy, "://"))
1028                        credential_from_url(&proxy_auth, curl_http_proxy);
1029                else {
1030                        struct strbuf url = STRBUF_INIT;
1031                        strbuf_addf(&url, "http://%s", curl_http_proxy);
1032                        credential_from_url(&proxy_auth, url.buf);
1033                        strbuf_release(&url);
1034                }
1035
1036                if (!proxy_auth.host)
1037                        die("Invalid proxy URL '%s'", curl_http_proxy);
1038
1039                curl_easy_setopt(result, CURLOPT_PROXY, proxy_auth.host);
1040#if LIBCURL_VERSION_NUM >= 0x071304
1041                var_override(&curl_no_proxy, getenv("NO_PROXY"));
1042                var_override(&curl_no_proxy, getenv("no_proxy"));
1043                curl_easy_setopt(result, CURLOPT_NOPROXY, curl_no_proxy);
1044#endif
1045        }
1046        init_curl_proxy_auth(result);
1047
1048        set_curl_keepalive(result);
1049
1050        return result;
1051}
1052
1053static void set_from_env(const char **var, const char *envname)
1054{
1055        const char *val = getenv(envname);
1056        if (val)
1057                *var = val;
1058}
1059
1060void http_init(struct remote *remote, const char *url, int proactive_auth)
1061{
1062        char *low_speed_limit;
1063        char *low_speed_time;
1064        char *normalized_url;
1065        struct urlmatch_config config = { STRING_LIST_INIT_DUP };
1066
1067        config.section = "http";
1068        config.key = NULL;
1069        config.collect_fn = http_options;
1070        config.cascade_fn = git_default_config;
1071        config.cb = NULL;
1072
1073        http_is_verbose = 0;
1074        normalized_url = url_normalize(url, &config.url);
1075
1076        git_config(urlmatch_config_entry, &config);
1077        free(normalized_url);
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
1180void 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        curl_slist_free_all(extra_http_headers);
1205        extra_http_headers = NULL;
1206
1207        curl_slist_free_all(pragma_header);
1208        pragma_header = NULL;
1209
1210        curl_slist_free_all(no_pragma_header);
1211        no_pragma_header = NULL;
1212
1213        if (curl_http_proxy) {
1214                free((void *)curl_http_proxy);
1215                curl_http_proxy = NULL;
1216        }
1217
1218        if (proxy_auth.password) {
1219                memset(proxy_auth.password, 0, strlen(proxy_auth.password));
1220                FREE_AND_NULL(proxy_auth.password);
1221        }
1222
1223        free((void *)curl_proxyuserpwd);
1224        curl_proxyuserpwd = NULL;
1225
1226        free((void *)http_proxy_authmethod);
1227        http_proxy_authmethod = NULL;
1228
1229        if (cert_auth.password != NULL) {
1230                memset(cert_auth.password, 0, strlen(cert_auth.password));
1231                FREE_AND_NULL(cert_auth.password);
1232        }
1233        ssl_cert_password_required = 0;
1234
1235        FREE_AND_NULL(cached_accept_language);
1236}
1237
1238struct active_request_slot *get_active_slot(void)
1239{
1240        struct active_request_slot *slot = active_queue_head;
1241        struct active_request_slot *newslot;
1242
1243#ifdef USE_CURL_MULTI
1244        int num_transfers;
1245
1246        /* Wait for a slot to open up if the queue is full */
1247        while (active_requests >= max_requests) {
1248                curl_multi_perform(curlm, &num_transfers);
1249                if (num_transfers < active_requests)
1250                        process_curl_messages();
1251        }
1252#endif
1253
1254        while (slot != NULL && slot->in_use)
1255                slot = slot->next;
1256
1257        if (slot == NULL) {
1258                newslot = xmalloc(sizeof(*newslot));
1259                newslot->curl = NULL;
1260                newslot->in_use = 0;
1261                newslot->next = NULL;
1262
1263                slot = active_queue_head;
1264                if (slot == NULL) {
1265                        active_queue_head = newslot;
1266                } else {
1267                        while (slot->next != NULL)
1268                                slot = slot->next;
1269                        slot->next = newslot;
1270                }
1271                slot = newslot;
1272        }
1273
1274        if (slot->curl == NULL) {
1275#ifdef NO_CURL_EASY_DUPHANDLE
1276                slot->curl = get_curl_handle();
1277#else
1278                slot->curl = curl_easy_duphandle(curl_default);
1279#endif
1280                curl_session_count++;
1281        }
1282
1283        active_requests++;
1284        slot->in_use = 1;
1285        slot->results = NULL;
1286        slot->finished = NULL;
1287        slot->callback_data = NULL;
1288        slot->callback_func = NULL;
1289        curl_easy_setopt(slot->curl, CURLOPT_COOKIEFILE, curl_cookie_file);
1290        if (curl_save_cookies)
1291                curl_easy_setopt(slot->curl, CURLOPT_COOKIEJAR, curl_cookie_file);
1292        curl_easy_setopt(slot->curl, CURLOPT_HTTPHEADER, pragma_header);
1293        curl_easy_setopt(slot->curl, CURLOPT_ERRORBUFFER, curl_errorstr);
1294        curl_easy_setopt(slot->curl, CURLOPT_CUSTOMREQUEST, NULL);
1295        curl_easy_setopt(slot->curl, CURLOPT_READFUNCTION, NULL);
1296        curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, NULL);
1297        curl_easy_setopt(slot->curl, CURLOPT_POSTFIELDS, NULL);
1298        curl_easy_setopt(slot->curl, CURLOPT_UPLOAD, 0);
1299        curl_easy_setopt(slot->curl, CURLOPT_HTTPGET, 1);
1300        curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 1);
1301        curl_easy_setopt(slot->curl, CURLOPT_RANGE, NULL);
1302
1303        /*
1304         * Default following to off unless "ALWAYS" is configured; this gives
1305         * callers a sane starting point, and they can tweak for individual
1306         * HTTP_FOLLOW_* cases themselves.
1307         */
1308        if (http_follow_config == HTTP_FOLLOW_ALWAYS)
1309                curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 1);
1310        else
1311                curl_easy_setopt(slot->curl, CURLOPT_FOLLOWLOCATION, 0);
1312
1313#if LIBCURL_VERSION_NUM >= 0x070a08
1314        curl_easy_setopt(slot->curl, CURLOPT_IPRESOLVE, git_curl_ipresolve);
1315#endif
1316#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1317        curl_easy_setopt(slot->curl, CURLOPT_HTTPAUTH, http_auth_methods);
1318#endif
1319        if (http_auth.password || curl_empty_auth_enabled())
1320                init_curl_http_auth(slot->curl);
1321
1322        return slot;
1323}
1324
1325int start_active_slot(struct active_request_slot *slot)
1326{
1327#ifdef USE_CURL_MULTI
1328        CURLMcode curlm_result = curl_multi_add_handle(curlm, slot->curl);
1329        int num_transfers;
1330
1331        if (curlm_result != CURLM_OK &&
1332            curlm_result != CURLM_CALL_MULTI_PERFORM) {
1333                warning("curl_multi_add_handle failed: %s",
1334                        curl_multi_strerror(curlm_result));
1335                active_requests--;
1336                slot->in_use = 0;
1337                return 0;
1338        }
1339
1340        /*
1341         * We know there must be something to do, since we just added
1342         * something.
1343         */
1344        curl_multi_perform(curlm, &num_transfers);
1345#endif
1346        return 1;
1347}
1348
1349#ifdef USE_CURL_MULTI
1350struct fill_chain {
1351        void *data;
1352        int (*fill)(void *);
1353        struct fill_chain *next;
1354};
1355
1356static struct fill_chain *fill_cfg;
1357
1358void add_fill_function(void *data, int (*fill)(void *))
1359{
1360        struct fill_chain *new_fill = xmalloc(sizeof(*new_fill));
1361        struct fill_chain **linkp = &fill_cfg;
1362        new_fill->data = data;
1363        new_fill->fill = fill;
1364        new_fill->next = NULL;
1365        while (*linkp)
1366                linkp = &(*linkp)->next;
1367        *linkp = new_fill;
1368}
1369
1370void fill_active_slots(void)
1371{
1372        struct active_request_slot *slot = active_queue_head;
1373
1374        while (active_requests < max_requests) {
1375                struct fill_chain *fill;
1376                for (fill = fill_cfg; fill; fill = fill->next)
1377                        if (fill->fill(fill->data))
1378                                break;
1379
1380                if (!fill)
1381                        break;
1382        }
1383
1384        while (slot != NULL) {
1385                if (!slot->in_use && slot->curl != NULL
1386                        && curl_session_count > min_curl_sessions) {
1387                        curl_easy_cleanup(slot->curl);
1388                        slot->curl = NULL;
1389                        curl_session_count--;
1390                }
1391                slot = slot->next;
1392        }
1393}
1394
1395void step_active_slots(void)
1396{
1397        int num_transfers;
1398        CURLMcode curlm_result;
1399
1400        do {
1401                curlm_result = curl_multi_perform(curlm, &num_transfers);
1402        } while (curlm_result == CURLM_CALL_MULTI_PERFORM);
1403        if (num_transfers < active_requests) {
1404                process_curl_messages();
1405                fill_active_slots();
1406        }
1407}
1408#endif
1409
1410void run_active_slot(struct active_request_slot *slot)
1411{
1412#ifdef USE_CURL_MULTI
1413        fd_set readfds;
1414        fd_set writefds;
1415        fd_set excfds;
1416        int max_fd;
1417        struct timeval select_timeout;
1418        int finished = 0;
1419
1420        slot->finished = &finished;
1421        while (!finished) {
1422                step_active_slots();
1423
1424                if (slot->in_use) {
1425#if LIBCURL_VERSION_NUM >= 0x070f04
1426                        long curl_timeout;
1427                        curl_multi_timeout(curlm, &curl_timeout);
1428                        if (curl_timeout == 0) {
1429                                continue;
1430                        } else if (curl_timeout == -1) {
1431                                select_timeout.tv_sec  = 0;
1432                                select_timeout.tv_usec = 50000;
1433                        } else {
1434                                select_timeout.tv_sec  =  curl_timeout / 1000;
1435                                select_timeout.tv_usec = (curl_timeout % 1000) * 1000;
1436                        }
1437#else
1438                        select_timeout.tv_sec  = 0;
1439                        select_timeout.tv_usec = 50000;
1440#endif
1441
1442                        max_fd = -1;
1443                        FD_ZERO(&readfds);
1444                        FD_ZERO(&writefds);
1445                        FD_ZERO(&excfds);
1446                        curl_multi_fdset(curlm, &readfds, &writefds, &excfds, &max_fd);
1447
1448                        /*
1449                         * It can happen that curl_multi_timeout returns a pathologically
1450                         * long timeout when curl_multi_fdset returns no file descriptors
1451                         * to read.  See commit message for more details.
1452                         */
1453                        if (max_fd < 0 &&
1454                            (select_timeout.tv_sec > 0 ||
1455                             select_timeout.tv_usec > 50000)) {
1456                                select_timeout.tv_sec  = 0;
1457                                select_timeout.tv_usec = 50000;
1458                        }
1459
1460                        select(max_fd+1, &readfds, &writefds, &excfds, &select_timeout);
1461                }
1462        }
1463#else
1464        while (slot->in_use) {
1465                slot->curl_result = curl_easy_perform(slot->curl);
1466                finish_active_slot(slot);
1467        }
1468#endif
1469}
1470
1471static void release_active_slot(struct active_request_slot *slot)
1472{
1473        closedown_active_slot(slot);
1474        if (slot->curl) {
1475                xmulti_remove_handle(slot);
1476                if (curl_session_count > min_curl_sessions) {
1477                        curl_easy_cleanup(slot->curl);
1478                        slot->curl = NULL;
1479                        curl_session_count--;
1480                }
1481        }
1482#ifdef USE_CURL_MULTI
1483        fill_active_slots();
1484#endif
1485}
1486
1487void finish_all_active_slots(void)
1488{
1489        struct active_request_slot *slot = active_queue_head;
1490
1491        while (slot != NULL)
1492                if (slot->in_use) {
1493                        run_active_slot(slot);
1494                        slot = active_queue_head;
1495                } else {
1496                        slot = slot->next;
1497                }
1498}
1499
1500/* Helpers for modifying and creating URLs */
1501static inline int needs_quote(int ch)
1502{
1503        if (((ch >= 'A') && (ch <= 'Z'))
1504                        || ((ch >= 'a') && (ch <= 'z'))
1505                        || ((ch >= '0') && (ch <= '9'))
1506                        || (ch == '/')
1507                        || (ch == '-')
1508                        || (ch == '.'))
1509                return 0;
1510        return 1;
1511}
1512
1513static char *quote_ref_url(const char *base, const char *ref)
1514{
1515        struct strbuf buf = STRBUF_INIT;
1516        const char *cp;
1517        int ch;
1518
1519        end_url_with_slash(&buf, base);
1520
1521        for (cp = ref; (ch = *cp) != 0; cp++)
1522                if (needs_quote(ch))
1523                        strbuf_addf(&buf, "%%%02x", ch);
1524                else
1525                        strbuf_addch(&buf, *cp);
1526
1527        return strbuf_detach(&buf, NULL);
1528}
1529
1530void append_remote_object_url(struct strbuf *buf, const char *url,
1531                              const char *hex,
1532                              int only_two_digit_prefix)
1533{
1534        end_url_with_slash(buf, url);
1535
1536        strbuf_addf(buf, "objects/%.*s/", 2, hex);
1537        if (!only_two_digit_prefix)
1538                strbuf_addstr(buf, hex + 2);
1539}
1540
1541char *get_remote_object_url(const char *url, const char *hex,
1542                            int only_two_digit_prefix)
1543{
1544        struct strbuf buf = STRBUF_INIT;
1545        append_remote_object_url(&buf, url, hex, only_two_digit_prefix);
1546        return strbuf_detach(&buf, NULL);
1547}
1548
1549void normalize_curl_result(CURLcode *result, long http_code,
1550                           char *errorstr, size_t errorlen)
1551{
1552        /*
1553         * If we see a failing http code with CURLE_OK, we have turned off
1554         * FAILONERROR (to keep the server's custom error response), and should
1555         * translate the code into failure here.
1556         *
1557         * Likewise, if we see a redirect (30x code), that means we turned off
1558         * redirect-following, and we should treat the result as an error.
1559         */
1560        if (*result == CURLE_OK && http_code >= 300) {
1561                *result = CURLE_HTTP_RETURNED_ERROR;
1562                /*
1563                 * Normally curl will already have put the "reason phrase"
1564                 * from the server into curl_errorstr; unfortunately without
1565                 * FAILONERROR it is lost, so we can give only the numeric
1566                 * status code.
1567                 */
1568                xsnprintf(errorstr, errorlen,
1569                          "The requested URL returned error: %ld",
1570                          http_code);
1571        }
1572}
1573
1574static int handle_curl_result(struct slot_results *results)
1575{
1576        normalize_curl_result(&results->curl_result, results->http_code,
1577                              curl_errorstr, sizeof(curl_errorstr));
1578
1579        if (results->curl_result == CURLE_OK) {
1580                credential_approve(&http_auth);
1581                if (proxy_auth.password)
1582                        credential_approve(&proxy_auth);
1583                return HTTP_OK;
1584        } else if (missing_target(results))
1585                return HTTP_MISSING_TARGET;
1586        else if (results->http_code == 401) {
1587                if (http_auth.username && http_auth.password) {
1588                        credential_reject(&http_auth);
1589                        return HTTP_NOAUTH;
1590                } else {
1591#ifdef LIBCURL_CAN_HANDLE_AUTH_ANY
1592                        http_auth_methods &= ~CURLAUTH_GSSNEGOTIATE;
1593                        if (results->auth_avail) {
1594                                http_auth_methods &= results->auth_avail;
1595                                http_auth_methods_restricted = 1;
1596                        }
1597#endif
1598                        return HTTP_REAUTH;
1599                }
1600        } else {
1601                if (results->http_connectcode == 407)
1602                        credential_reject(&proxy_auth);
1603#if LIBCURL_VERSION_NUM >= 0x070c00
1604                if (!curl_errorstr[0])
1605                        strlcpy(curl_errorstr,
1606                                curl_easy_strerror(results->curl_result),
1607                                sizeof(curl_errorstr));
1608#endif
1609                return HTTP_ERROR;
1610        }
1611}
1612
1613int run_one_slot(struct active_request_slot *slot,
1614                 struct slot_results *results)
1615{
1616        slot->results = results;
1617        if (!start_active_slot(slot)) {
1618                xsnprintf(curl_errorstr, sizeof(curl_errorstr),
1619                          "failed to start HTTP request");
1620                return HTTP_START_FAILED;
1621        }
1622
1623        run_active_slot(slot);
1624        return handle_curl_result(results);
1625}
1626
1627struct curl_slist *http_copy_default_headers(void)
1628{
1629        struct curl_slist *headers = NULL, *h;
1630
1631        for (h = extra_http_headers; h; h = h->next)
1632                headers = curl_slist_append(headers, h->data);
1633
1634        return headers;
1635}
1636
1637static 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 */
1657static 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 */
1692static 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
1726static 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 */
1825static 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
1837static 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
1848static 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 */
1951static 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
1978static 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
2026int 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 */
2039static 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;
2059cleanup:
2060        strbuf_release(&tmpfile);
2061        return ret;
2062}
2063
2064int 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 */
2090static 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
2114static 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
2149add_pack:
2150        new_pack->next = *packs_head;
2151        *packs_head = new_pack;
2152        return 0;
2153}
2154
2155int 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
2187cleanup:
2188        free(url);
2189        return ret;
2190}
2191
2192void 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
2204int 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
2253struct 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
2300abort:
2301        strbuf_release(&preq->tmpfile);
2302        free(preq->url);
2303        free(preq);
2304        return NULL;
2305}
2306
2307/* Helpers for fetching objects (loose) */
2308static 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
2347struct 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
2470abort:
2471        strbuf_release(&prevfile);
2472        free(freq->url);
2473        free(freq);
2474        return NULL;
2475}
2476
2477void 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
2486int 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
2522void 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
2529void 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}