http-backend.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "pkt-line.h"
   4 #include "object.h"
   5 #include "tag.h"
   6 #include "exec_cmd.h"
   7 #include "run-command.h"
   8 #include "string-list.h"
   9 #include "url.h"
  10 #include "argv-array.h"
  11
  12 static const char content_type[] = "Content-Type";
  13 static const char content_length[] = "Content-Length";
  14 static const char last_modified[] = "Last-Modified";
  15 static int getanyfile = 1;
  16 static unsigned long max_request_buffer = 10 * 1024 * 1024;
  17
  18 static struct string_list *query_params;
  19
  20 struct rpc_service {
  21         const char *name;
  22         const char *config_name;
  23         unsigned buffer_input : 1;
  24         signed enabled : 2;
  25 };
  26
  27 static struct rpc_service rpc_service[] = {
  28         { "upload-pack", "uploadpack", 1, 1 },
  29         { "receive-pack", "receivepack", 0, -1 },
  30 };
  31
  32 static struct string_list *get_parameters(void)
  33 {
  34         if (!query_params) {
  35                 const char *query = getenv("QUERY_STRING");
  36
  37                 query_params = xcalloc(1, sizeof(*query_params));
  38                 while (query && *query) {
  39                         char *name = url_decode_parameter_name(&query);
  40                         char *value = url_decode_parameter_value(&query);
  41                         struct string_list_item *i;
  42
  43                         i = string_list_lookup(query_params, name);
  44                         if (!i)
  45                                 i = string_list_insert(query_params, name);
  46                         else
  47                                 free(i->util);
  48                         i->util = value;
  49                 }
  50         }
  51         return query_params;
  52 }
  53
  54 static const char *get_parameter(const char *name)
  55 {
  56         struct string_list_item *i;
  57         i = string_list_lookup(get_parameters(), name);
  58         return i ? i->util : NULL;
  59 }
  60
  61 __attribute__((format (printf, 2, 3)))
  62 static void format_write(int fd, const char *fmt, ...)
  63 {
  64         static char buffer[1024];
  65
  66         va_list args;
  67         unsigned n;
  68
  69         va_start(args, fmt);
  70         n = vsnprintf(buffer, sizeof(buffer), fmt, args);
  71         va_end(args);
  72         if (n >= sizeof(buffer))
  73                 die("protocol error: impossibly long line");
  74
  75         write_or_die(fd, buffer, n);
  76 }
  77
  78 static void http_status(struct strbuf *hdr, unsigned code, const char *msg)
  79 {
  80         strbuf_addf(hdr, "Status: %u %s\r\n", code, msg);
  81 }
  82
  83 static void hdr_str(struct strbuf *hdr, const char *name, const char *value)
  84 {
  85         strbuf_addf(hdr, "%s: %s\r\n", name, value);
  86 }
  87
  88 static void hdr_int(struct strbuf *hdr, const char *name, uintmax_t value)
  89 {
  90         strbuf_addf(hdr, "%s: %" PRIuMAX "\r\n", name, value);
  91 }
  92
  93 static void hdr_date(struct strbuf *hdr, const char *name, unsigned long when)
  94 {
  95         const char *value = show_date(when, 0, DATE_MODE(RFC2822));
  96         hdr_str(hdr, name, value);
  97 }
  98
  99 static void hdr_nocache(struct strbuf *hdr)
 100 {
 101         hdr_str(hdr, "Expires", "Fri, 01 Jan 1980 00:00:00 GMT");
 102         hdr_str(hdr, "Pragma", "no-cache");
 103         hdr_str(hdr, "Cache-Control", "no-cache, max-age=0, must-revalidate");
 104 }
 105
 106 static void hdr_cache_forever(struct strbuf *hdr)
 107 {
 108         unsigned long now = time(NULL);
 109         hdr_date(hdr, "Date", now);
 110         hdr_date(hdr, "Expires", now + 31536000);
 111         hdr_str(hdr, "Cache-Control", "public, max-age=31536000");
 112 }
 113
 114 static void end_headers(struct strbuf *hdr)
 115 {
 116         strbuf_add(hdr, "\r\n", 2);
 117         write_or_die(1, hdr->buf, hdr->len);
 118         strbuf_release(hdr);
 119 }
 120
 121 __attribute__((format (printf, 2, 3)))
 122 static NORETURN void not_found(struct strbuf *hdr, const char *err, ...)
 123 {
 124         va_list params;
 125
 126         http_status(hdr, 404, "Not Found");
 127         hdr_nocache(hdr);
 128         end_headers(hdr);
 129
 130         va_start(params, err);
 131         if (err && *err)
 132                 vfprintf(stderr, err, params);
 133         va_end(params);
 134         exit(0);
 135 }
 136
 137 __attribute__((format (printf, 2, 3)))
 138 static NORETURN void forbidden(struct strbuf *hdr, const char *err, ...)
 139 {
 140         va_list params;
 141
 142         http_status(hdr, 403, "Forbidden");
 143         hdr_nocache(hdr);
 144         end_headers(hdr);
 145
 146         va_start(params, err);
 147         if (err && *err)
 148                 vfprintf(stderr, err, params);
 149         va_end(params);
 150         exit(0);
 151 }
 152
 153 static void select_getanyfile(struct strbuf *hdr)
 154 {
 155         if (!getanyfile)
 156                 forbidden(hdr, "Unsupported service: getanyfile");
 157 }
 158
 159 static void send_strbuf(struct strbuf *hdr,
 160                         const char *type, struct strbuf *buf)
 161 {
 162         hdr_int(hdr, content_length, buf->len);
 163         hdr_str(hdr, content_type, type);
 164         end_headers(hdr);
 165         write_or_die(1, buf->buf, buf->len);
 166 }
 167
 168 static void send_local_file(struct strbuf *hdr, const char *the_type,
 169                                 const char *name)
 170 {
 171         char *p = git_pathdup("%s", name);
 172         size_t buf_alloc = 8192;
 173         char *buf = xmalloc(buf_alloc);
 174         int fd;
 175         struct stat sb;
 176
 177         fd = open(p, O_RDONLY);
 178         if (fd < 0)
 179                 not_found(hdr, "Cannot open '%s': %s", p, strerror(errno));
 180         if (fstat(fd, &sb) < 0)
 181                 die_errno("Cannot stat '%s'", p);
 182
 183         hdr_int(hdr, content_length, sb.st_size);
 184         hdr_str(hdr, content_type, the_type);
 185         hdr_date(hdr, last_modified, sb.st_mtime);
 186         end_headers(hdr);
 187
 188         for (;;) {
 189                 ssize_t n = xread(fd, buf, buf_alloc);
 190                 if (n < 0)
 191                         die_errno("Cannot read '%s'", p);
 192                 if (!n)
 193                         break;
 194                 write_or_die(1, buf, n);
 195         }
 196         close(fd);
 197         free(buf);
 198         free(p);
 199 }
 200
 201 static void get_text_file(struct strbuf *hdr, char *name)
 202 {
 203         select_getanyfile(hdr);
 204         hdr_nocache(hdr);
 205         send_local_file(hdr, "text/plain", name);
 206 }
 207
 208 static void get_loose_object(struct strbuf *hdr, char *name)
 209 {
 210         select_getanyfile(hdr);
 211         hdr_cache_forever(hdr);
 212         send_local_file(hdr, "application/x-git-loose-object", name);
 213 }
 214
 215 static void get_pack_file(struct strbuf *hdr, char *name)
 216 {
 217         select_getanyfile(hdr);
 218         hdr_cache_forever(hdr);
 219         send_local_file(hdr, "application/x-git-packed-objects", name);
 220 }
 221
 222 static void get_idx_file(struct strbuf *hdr, char *name)
 223 {
 224         select_getanyfile(hdr);
 225         hdr_cache_forever(hdr);
 226         send_local_file(hdr, "application/x-git-packed-objects-toc", name);
 227 }
 228
 229 static void http_config(void)
 230 {
 231         int i, value = 0;
 232         struct strbuf var = STRBUF_INIT;
 233
 234         git_config_get_bool("http.getanyfile", &getanyfile);
 235         git_config_get_ulong("http.maxrequestbuffer", &max_request_buffer);
 236
 237         for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
 238                 struct rpc_service *svc = &rpc_service[i];
 239                 strbuf_addf(&var, "http.%s", svc->config_name);
 240                 if (!git_config_get_bool(var.buf, &value))
 241                         svc->enabled = value;
 242                 strbuf_reset(&var);
 243         }
 244
 245         strbuf_release(&var);
 246 }
 247
 248 static struct rpc_service *select_service(struct strbuf *hdr, const char *name)
 249 {
 250         const char *svc_name;
 251         struct rpc_service *svc = NULL;
 252         int i;
 253
 254         if (!skip_prefix(name, "git-", &svc_name))
 255                 forbidden(hdr, "Unsupported service: '%s'", name);
 256
 257         for (i = 0; i < ARRAY_SIZE(rpc_service); i++) {
 258                 struct rpc_service *s = &rpc_service[i];
 259                 if (!strcmp(s->name, svc_name)) {
 260                         svc = s;
 261                         break;
 262                 }
 263         }
 264
 265         if (!svc)
 266                 forbidden(hdr, "Unsupported service: '%s'", name);
 267
 268         if (svc->enabled < 0) {
 269                 const char *user = getenv("REMOTE_USER");
 270                 svc->enabled = (user && *user) ? 1 : 0;
 271         }
 272         if (!svc->enabled)
 273                 forbidden(hdr, "Service not enabled: '%s'", svc->name);
 274         return svc;
 275 }
 276
 277 /*
 278  * This is basically strbuf_read(), except that if we
 279  * hit max_request_buffer we die (we'd rather reject a
 280  * maliciously large request than chew up infinite memory).
 281  */
 282 static ssize_t read_request(int fd, unsigned char **out)
 283 {
 284         size_t len = 0, alloc = 8192;
 285         unsigned char *buf = xmalloc(alloc);
 286
 287         if (max_request_buffer < alloc)
 288                 max_request_buffer = alloc;
 289
 290         while (1) {
 291                 ssize_t cnt;
 292
 293                 cnt = read_in_full(fd, buf + len, alloc - len);
 294                 if (cnt < 0) {
 295                         free(buf);
 296                         return -1;
 297                 }
 298
 299                 /* partial read from read_in_full means we hit EOF */
 300                 len += cnt;
 301                 if (len < alloc) {
 302                         *out = buf;
 303                         return len;
 304                 }
 305
 306                 /* otherwise, grow and try again (if we can) */
 307                 if (alloc == max_request_buffer)
 308                         die("request was larger than our maximum size (%lu);"
 309                             " try setting GIT_HTTP_MAX_REQUEST_BUFFER",
 310                             max_request_buffer);
 311
 312                 alloc = alloc_nr(alloc);
 313                 if (alloc > max_request_buffer)
 314                         alloc = max_request_buffer;
 315                 REALLOC_ARRAY(buf, alloc);
 316         }
 317 }
 318
 319 static void inflate_request(const char *prog_name, int out, int buffer_input)
 320 {
 321         git_zstream stream;
 322         unsigned char *full_request = NULL;
 323         unsigned char in_buf[8192];
 324         unsigned char out_buf[8192];
 325         unsigned long cnt = 0;
 326
 327         memset(&stream, 0, sizeof(stream));
 328         git_inflate_init_gzip_only(&stream);
 329
 330         while (1) {
 331                 ssize_t n;
 332
 333                 if (buffer_input) {
 334                         if (full_request)
 335                                 n = 0; /* nothing left to read */
 336                         else
 337                                 n = read_request(0, &full_request);
 338                         stream.next_in = full_request;
 339                 } else {
 340                         n = xread(0, in_buf, sizeof(in_buf));
 341                         stream.next_in = in_buf;
 342                 }
 343
 344                 if (n <= 0)
 345                         die("request ended in the middle of the gzip stream");
 346                 stream.avail_in = n;
 347
 348                 while (0 < stream.avail_in) {
 349                         int ret;
 350
 351                         stream.next_out = out_buf;
 352                         stream.avail_out = sizeof(out_buf);
 353
 354                         ret = git_inflate(&stream, Z_NO_FLUSH);
 355                         if (ret != Z_OK && ret != Z_STREAM_END)
 356                                 die("zlib error inflating request, result %d", ret);
 357
 358                         n = stream.total_out - cnt;
 359                         if (write_in_full(out, out_buf, n) != n)
 360                                 die("%s aborted reading request", prog_name);
 361                         cnt += n;
 362
 363                         if (ret == Z_STREAM_END)
 364                                 goto done;
 365                 }
 366         }
 367
 368 done:
 369         git_inflate_end(&stream);
 370         close(out);
 371         free(full_request);
 372 }
 373
 374 static void copy_request(const char *prog_name, int out)
 375 {
 376         unsigned char *buf;
 377         ssize_t n = read_request(0, &buf);
 378         if (n < 0)
 379                 die_errno("error reading request body");
 380         if (write_in_full(out, buf, n) != n)
 381                 die("%s aborted reading request", prog_name);
 382         close(out);
 383         free(buf);
 384 }
 385
 386 static void run_service(const char **argv, int buffer_input)
 387 {
 388         const char *encoding = getenv("HTTP_CONTENT_ENCODING");
 389         const char *user = getenv("REMOTE_USER");
 390         const char *host = getenv("REMOTE_ADDR");
 391         int gzipped_request = 0;
 392         struct child_process cld = CHILD_PROCESS_INIT;
 393
 394         if (encoding && !strcmp(encoding, "gzip"))
 395                 gzipped_request = 1;
 396         else if (encoding && !strcmp(encoding, "x-gzip"))
 397                 gzipped_request = 1;
 398
 399         if (!user || !*user)
 400                 user = "anonymous";
 401         if (!host || !*host)
 402                 host = "(none)";
 403
 404         if (!getenv("GIT_COMMITTER_NAME"))
 405                 argv_array_pushf(&cld.env_array, "GIT_COMMITTER_NAME=%s", user);
 406         if (!getenv("GIT_COMMITTER_EMAIL"))
 407                 argv_array_pushf(&cld.env_array,
 408                                  "GIT_COMMITTER_EMAIL=%s@http.%s", user, host);
 409
 410         cld.argv = argv;
 411         if (buffer_input || gzipped_request)
 412                 cld.in = -1;
 413         cld.git_cmd = 1;
 414         if (start_command(&cld))
 415                 exit(1);
 416
 417         close(1);
 418         if (gzipped_request)
 419                 inflate_request(argv[0], cld.in, buffer_input);
 420         else if (buffer_input)
 421                 copy_request(argv[0], cld.in);
 422         else
 423                 close(0);
 424
 425         if (finish_command(&cld))
 426                 exit(1);
 427 }
 428
 429 static int show_text_ref(const char *name, const struct object_id *oid,
 430                          int flag, void *cb_data)
 431 {
 432         const char *name_nons = strip_namespace(name);
 433         struct strbuf *buf = cb_data;
 434         struct object *o = parse_object(oid->hash);
 435         if (!o)
 436                 return 0;
 437
 438         strbuf_addf(buf, "%s\t%s\n", oid_to_hex(oid), name_nons);
 439         if (o->type == OBJ_TAG) {
 440                 o = deref_tag(o, name, 0);
 441                 if (!o)
 442                         return 0;
 443                 strbuf_addf(buf, "%s\t%s^{}\n", oid_to_hex(&o->oid),
 444                             name_nons);
 445         }
 446         return 0;
 447 }
 448
 449 static void get_info_refs(struct strbuf *hdr, char *arg)
 450 {
 451         const char *service_name = get_parameter("service");
 452         struct strbuf buf = STRBUF_INIT;
 453
 454         hdr_nocache(hdr);
 455
 456         if (service_name) {
 457                 const char *argv[] = {NULL /* service name */,
 458                         "--stateless-rpc", "--advertise-refs",
 459                         ".", NULL};
 460                 struct rpc_service *svc = select_service(hdr, service_name);
 461
 462                 strbuf_addf(&buf, "application/x-git-%s-advertisement",
 463                         svc->name);
 464                 hdr_str(hdr, content_type, buf.buf);
 465                 end_headers(hdr);
 466
 467                 packet_write(1, "# service=git-%s\n", svc->name);
 468                 packet_flush(1);
 469
 470                 argv[0] = svc->name;
 471                 run_service(argv, 0);
 472
 473         } else {
 474                 select_getanyfile(hdr);
 475                 for_each_namespaced_ref(show_text_ref, &buf);
 476                 send_strbuf(hdr, "text/plain", &buf);
 477         }
 478         strbuf_release(&buf);
 479 }
 480
 481 static int show_head_ref(const char *refname, const struct object_id *oid,
 482                          int flag, void *cb_data)
 483 {
 484         struct strbuf *buf = cb_data;
 485
 486         if (flag & REF_ISSYMREF) {
 487                 struct object_id unused;
 488                 const char *target = resolve_ref_unsafe(refname,
 489                                                         RESOLVE_REF_READING,
 490                                                         unused.hash, NULL);
 491
 492                 if (target)
 493                         strbuf_addf(buf, "ref: %s\n", strip_namespace(target));
 494         } else {
 495                 strbuf_addf(buf, "%s\n", oid_to_hex(oid));
 496         }
 497
 498         return 0;
 499 }
 500
 501 static void get_head(struct strbuf *hdr, char *arg)
 502 {
 503         struct strbuf buf = STRBUF_INIT;
 504
 505         select_getanyfile(hdr);
 506         head_ref_namespaced(show_head_ref, &buf);
 507         send_strbuf(hdr, "text/plain", &buf);
 508         strbuf_release(&buf);
 509 }
 510
 511 static void get_info_packs(struct strbuf *hdr, char *arg)
 512 {
 513         size_t objdirlen = strlen(get_object_directory());
 514         struct strbuf buf = STRBUF_INIT;
 515         struct packed_git *p;
 516         size_t cnt = 0;
 517
 518         select_getanyfile(hdr);
 519         prepare_packed_git();
 520         for (p = packed_git; p; p = p->next) {
 521                 if (p->pack_local)
 522                         cnt++;
 523         }
 524
 525         strbuf_grow(&buf, cnt * 53 + 2);
 526         for (p = packed_git; p; p = p->next) {
 527                 if (p->pack_local)
 528                         strbuf_addf(&buf, "P %s\n", p->pack_name + objdirlen + 6);
 529         }
 530         strbuf_addch(&buf, '\n');
 531
 532         hdr_nocache(hdr);
 533         send_strbuf(hdr, "text/plain; charset=utf-8", &buf);
 534         strbuf_release(&buf);
 535 }
 536
 537 static void check_content_type(struct strbuf *hdr, const char *accepted_type)
 538 {
 539         const char *actual_type = getenv("CONTENT_TYPE");
 540
 541         if (!actual_type)
 542                 actual_type = "";
 543
 544         if (strcmp(actual_type, accepted_type)) {
 545                 http_status(hdr, 415, "Unsupported Media Type");
 546                 hdr_nocache(hdr);
 547                 end_headers(hdr);
 548                 format_write(1,
 549                         "Expected POST with Content-Type '%s',"
 550                         " but received '%s' instead.\n",
 551                         accepted_type, actual_type);
 552                 exit(0);
 553         }
 554 }
 555
 556 static void service_rpc(struct strbuf *hdr, char *service_name)
 557 {
 558         const char *argv[] = {NULL, "--stateless-rpc", ".", NULL};
 559         struct rpc_service *svc = select_service(hdr, service_name);
 560         struct strbuf buf = STRBUF_INIT;
 561
 562         strbuf_reset(&buf);
 563         strbuf_addf(&buf, "application/x-git-%s-request", svc->name);
 564         check_content_type(hdr, buf.buf);
 565
 566         hdr_nocache(hdr);
 567
 568         strbuf_reset(&buf);
 569         strbuf_addf(&buf, "application/x-git-%s-result", svc->name);
 570         hdr_str(hdr, content_type, buf.buf);
 571
 572         end_headers(hdr);
 573
 574         argv[0] = svc->name;
 575         run_service(argv, svc->buffer_input);
 576         strbuf_release(&buf);
 577 }
 578
 579 static int dead;
 580 static NORETURN void die_webcgi(const char *err, va_list params)
 581 {
 582         if (dead <= 1) {
 583                 struct strbuf hdr = STRBUF_INIT;
 584
 585                 vreportf("fatal: ", err, params);
 586
 587                 http_status(&hdr, 500, "Internal Server Error");
 588                 hdr_nocache(&hdr);
 589                 end_headers(&hdr);
 590         }
 591         exit(0); /* we successfully reported a failure ;-) */
 592 }
 593
 594 static int die_webcgi_recursing(void)
 595 {
 596         return dead++ > 1;
 597 }
 598
 599 static char* getdir(void)
 600 {
 601         struct strbuf buf = STRBUF_INIT;
 602         char *pathinfo = getenv("PATH_INFO");
 603         char *root = getenv("GIT_PROJECT_ROOT");
 604         char *path = getenv("PATH_TRANSLATED");
 605
 606         if (root && *root) {
 607                 if (!pathinfo || !*pathinfo)
 608                         die("GIT_PROJECT_ROOT is set but PATH_INFO is not");
 609                 if (daemon_avoid_alias(pathinfo))
 610                         die("'%s': aliased", pathinfo);
 611                 end_url_with_slash(&buf, root);
 612                 if (pathinfo[0] == '/')
 613                         pathinfo++;
 614                 strbuf_addstr(&buf, pathinfo);
 615                 return strbuf_detach(&buf, NULL);
 616         } else if (path && *path) {
 617                 return xstrdup(path);
 618         } else
 619                 die("No GIT_PROJECT_ROOT or PATH_TRANSLATED from server");
 620         return NULL;
 621 }
 622
 623 static struct service_cmd {
 624         const char *method;
 625         const char *pattern;
 626         void (*imp)(struct strbuf *, char *);
 627 } services[] = {
 628         {"GET", "/HEAD$", get_head},
 629         {"GET", "/info/refs$", get_info_refs},
 630         {"GET", "/objects/info/alternates$", get_text_file},
 631         {"GET", "/objects/info/http-alternates$", get_text_file},
 632         {"GET", "/objects/info/packs$", get_info_packs},
 633         {"GET", "/objects/[0-9a-f]{2}/[0-9a-f]{38}$", get_loose_object},
 634         {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.pack$", get_pack_file},
 635         {"GET", "/objects/pack/pack-[0-9a-f]{40}\\.idx$", get_idx_file},
 636
 637         {"POST", "/git-upload-pack$", service_rpc},
 638         {"POST", "/git-receive-pack$", service_rpc}
 639 };
 640
 641 static int bad_request(struct strbuf *hdr, const struct service_cmd *c)
 642 {
 643         const char *proto = getenv("SERVER_PROTOCOL");
 644
 645         if (proto && !strcmp(proto, "HTTP/1.1")) {
 646                 http_status(hdr, 405, "Method Not Allowed");
 647                 hdr_str(hdr, "Allow",
 648                         !strcmp(c->method, "GET") ? "GET, HEAD" : c->method);
 649         } else
 650                 http_status(hdr, 400, "Bad Request");
 651         hdr_nocache(hdr);
 652         end_headers(hdr);
 653         return 0;
 654 }
 655
 656 int cmd_main(int argc, const char **argv)
 657 {
 658         char *method = getenv("REQUEST_METHOD");
 659         char *dir;
 660         struct service_cmd *cmd = NULL;
 661         char *cmd_arg = NULL;
 662         int i;
 663         struct strbuf hdr = STRBUF_INIT;
 664
 665         set_die_routine(die_webcgi);
 666         set_die_is_recursing_routine(die_webcgi_recursing);
 667
 668         if (!method)
 669                 die("No REQUEST_METHOD from server");
 670         if (!strcmp(method, "HEAD"))
 671                 method = "GET";
 672         dir = getdir();
 673
 674         for (i = 0; i < ARRAY_SIZE(services); i++) {
 675                 struct service_cmd *c = &services[i];
 676                 regex_t re;
 677                 regmatch_t out[1];
 678
 679                 if (regcomp(&re, c->pattern, REG_EXTENDED))
 680                         die("Bogus regex in service table: %s", c->pattern);
 681                 if (!regexec(&re, dir, 1, out, 0)) {
 682                         size_t n;
 683
 684                         if (strcmp(method, c->method))
 685                                 return bad_request(&hdr, c);
 686
 687                         cmd = c;
 688                         n = out[0].rm_eo - out[0].rm_so;
 689                         cmd_arg = xmemdupz(dir + out[0].rm_so + 1, n - 1);
 690                         dir[out[0].rm_so] = 0;
 691                         break;
 692                 }
 693                 regfree(&re);
 694         }
 695
 696         if (!cmd)
 697                 not_found(&hdr, "Request not supported: '%s'", dir);
 698
 699         setup_path();
 700         if (!enter_repo(dir, 0))
 701                 not_found(&hdr, "Not a git repository: '%s'", dir);
 702         if (!getenv("GIT_HTTP_EXPORT_ALL") &&
 703             access("git-daemon-export-ok", F_OK) )
 704                 not_found(&hdr, "Repository not exported: '%s'", dir);
 705
 706         http_config();
 707         max_request_buffer = git_env_ulong("GIT_HTTP_MAX_REQUEST_BUFFER",
 708                                            max_request_buffer);
 709
 710         cmd->imp(&hdr, cmd_arg);
 711         return 0;
 712 }