package/uhttpd/src/uhttpd.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd - Main component
   3  *
   4  *   Copyright (C) 2010 Jo-Philipp Wich <xm@subsignal.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #define _XOPEN_SOURCE 500       /* crypt() */
  20
  21 #include "uhttpd.h"
  22 #include "uhttpd-utils.h"
  23 #include "uhttpd-file.h"
  24
  25 #ifdef HAVE_CGI
  26 #include "uhttpd-cgi.h"
  27 #endif
  28
  29 #ifdef HAVE_LUA
  30 #include "uhttpd-lua.h"
  31 #endif
  32
  33 #ifdef HAVE_TLS
  34 #include "uhttpd-tls.h"
  35 #endif
  36
  37
  38 static int run = 1;
  39
  40 static void uh_sigterm(int sig)
  41 {
  42         run = 0;
  43 }
  44
  45 static void uh_sigchld(int sig)
  46 {
  47         while( waitpid(-1, NULL, WNOHANG) > 0 ) { }
  48 }
  49
  50 static void uh_config_parse(struct config *conf)
  51 {
  52         FILE *c;
  53         char line[512];
  54         char *user = NULL;
  55         char *pass = NULL;
  56         char *eol  = NULL;
  57
  58         const char *path = conf->file ? conf->file : "/etc/httpd.conf";
  59
  60
  61         if( (c = fopen(path, "r")) != NULL )
  62         {
  63                 memset(line, 0, sizeof(line));
  64
  65                 while( fgets(line, sizeof(line) - 1, c) )
  66                 {
  67                         if( (line[0] == '/') && (strchr(line, ':') != NULL) )
  68                         {
  69                                 if( !(user = strchr(line, ':')) || (*user++ = 0) ||
  70                                     !(pass = strchr(user, ':')) || (*pass++ = 0) ||
  71                                         !(eol = strchr(pass, '\n')) || (*eol++  = 0) )
  72                                                 continue;
  73
  74                                 if( !uh_auth_add(line, user, pass) )
  75                                 {
  76                                         fprintf(stderr,
  77                                                 "Notice: No password set for user %s, ignoring "
  78                                                 "authentication on %s\n", user, line
  79                                         );
  80                                 }
  81                         }
  82                         else if( !strncmp(line, "I:", 2) )
  83                         {
  84                                 if( !(user = strchr(line, ':')) || (*user++ = 0) ||
  85                                     !(eol = strchr(user, '\n')) || (*eol++  = 0) )
  86                                         continue;
  87
  88                                 conf->index_file = strdup(user);
  89                         }
  90                         else if( !strncmp(line, "E404:", 5) )
  91                         {
  92                                 if( !(user = strchr(line, ':')) || (*user++ = 0) ||
  93                                     !(eol = strchr(user, '\n')) || (*eol++  = 0) )
  94                                                 continue;
  95
  96                                 conf->error_handler = strdup(user);
  97                         }
  98                 }
  99
 100                 fclose(c);
 101         }
 102 }
 103
 104 static int uh_socket_bind(
 105         fd_set *serv_fds, int *max_fd, const char *host, const char *port,
 106         struct addrinfo *hints, int do_tls, struct config *conf
 107 ) {
 108         int sock = -1;
 109         int yes = 1;
 110         int status;
 111         int bound = 0;
 112
 113         struct listener *l = NULL;
 114         struct addrinfo *addrs = NULL, *p = NULL;
 115
 116         if( (status = getaddrinfo(host, port, hints, &addrs)) != 0 )
 117         {
 118                 fprintf(stderr, "getaddrinfo(): %s\n", gai_strerror(status));
 119         }
 120
 121         /* try to bind a new socket to each found address */
 122         for( p = addrs; p; p = p->ai_next )
 123         {
 124                 /* get the socket */
 125                 if( (sock = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1 )
 126                 {
 127                         perror("socket()");
 128                         goto error;
 129                 }
 130
 131                 /* "address already in use" */
 132                 if( setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) == -1 )
 133                 {
 134                         perror("setsockopt()");
 135                         goto error;
 136                 }
 137
 138                 /* required to get parallel v4 + v6 working */
 139                 if( p->ai_family == AF_INET6 )
 140                 {
 141                         if( setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &yes, sizeof(yes)) == -1 )
 142                         {
 143                                 perror("setsockopt()");
 144                                 goto error;
 145                         }
 146                 }
 147
 148                 /* bind */
 149                 if( bind(sock, p->ai_addr, p->ai_addrlen) == -1 )
 150                 {
 151                         perror("bind()");
 152                         goto error;
 153                 }
 154
 155                 /* listen */
 156                 if( listen(sock, UH_LIMIT_CLIENTS) == -1 )
 157                 {
 158                         perror("listen()");
 159                         goto error;
 160                 }
 161
 162                 /* add listener to global list */
 163                 if( ! (l = uh_listener_add(sock, conf)) )
 164                 {
 165                         fprintf(stderr,
 166                                 "uh_listener_add(): Can not create more than "
 167                                 "%i listen sockets\n", UH_LIMIT_LISTENERS
 168                         );
 169
 170                         goto error;
 171                 }
 172
 173 #ifdef HAVE_TLS
 174                 /* init TLS */
 175                 l->tls = do_tls ? conf->tls : NULL;
 176 #endif
 177
 178                 /* add socket to server fd set */
 179                 FD_SET(sock, serv_fds);
 180                 fd_cloexec(sock);
 181                 *max_fd = max(*max_fd, sock);
 182
 183                 bound++;
 184                 continue;
 185
 186                 error:
 187                 if( sock > 0 )
 188                         close(sock);
 189         }
 190
 191         freeaddrinfo(addrs);
 192
 193         return bound;
 194 }
 195
 196 static struct http_request * uh_http_header_parse(struct client *cl, char *buffer, int buflen)
 197 {
 198         char *method  = &buffer[0];
 199         char *path    = NULL;
 200         char *version = NULL;
 201
 202         char *headers = NULL;
 203         char *hdrname = NULL;
 204         char *hdrdata = NULL;
 205
 206         int i;
 207         int hdrcount = 0;
 208
 209         static struct http_request req;
 210
 211         memset(&req, 0, sizeof(req));
 212
 213
 214         /* terminate initial header line */
 215         if( (headers = strfind(buffer, buflen, "\r\n", 2)) != NULL )
 216         {
 217                 buffer[buflen-1] = 0;
 218
 219                 *headers++ = 0;
 220                 *headers++ = 0;
 221
 222                 /* find request path */
 223                 if( (path = strchr(buffer, ' ')) != NULL )
 224                         *path++ = 0;
 225
 226                 /* find http version */
 227                 if( (path != NULL) && ((version = strchr(path, ' ')) != NULL) )
 228                         *version++ = 0;
 229
 230
 231                 /* check method */
 232                 if( strcmp(method, "GET") && strcmp(method, "HEAD") && strcmp(method, "POST") )
 233                 {
 234                         /* invalid method */
 235                         uh_http_response(cl, 405, "Method Not Allowed");
 236                         return NULL;
 237                 }
 238                 else
 239                 {
 240                         switch(method[0])
 241                         {
 242                                 case 'G':
 243                                         req.method = UH_HTTP_MSG_GET;
 244                                         break;
 245
 246                                 case 'H':
 247                                         req.method = UH_HTTP_MSG_HEAD;
 248                                         break;
 249
 250                                 case 'P':
 251                                         req.method = UH_HTTP_MSG_POST;
 252                                         break;
 253                         }
 254                 }
 255
 256                 /* check path */
 257                 if( !path || !strlen(path) )
 258                 {
 259                         /* malformed request */
 260                         uh_http_response(cl, 400, "Bad Request");
 261                         return NULL;
 262                 }
 263                 else
 264                 {
 265                         req.url = path;
 266                 }
 267
 268                 /* check version */
 269                 if( strcmp(version, "HTTP/0.9") && strcmp(version, "HTTP/1.0") && strcmp(version, "HTTP/1.1") )
 270                 {
 271                         /* unsupported version */
 272                         uh_http_response(cl, 400, "Bad Request");
 273                         return NULL;
 274                 }
 275                 else
 276                 {
 277                         req.version = strtof(&version[5], NULL);
 278                 }
 279
 280
 281                 /* process header fields */
 282                 for( i = (int)(headers - buffer); i < buflen; i++ )
 283                 {
 284                         /* found eol and have name + value, push out header tuple */
 285                         if( hdrname && hdrdata && (buffer[i] == '\r' || buffer[i] == '\n') )
 286                         {
 287                                 buffer[i] = 0;
 288
 289                                 /* store */
 290                                 if( (hdrcount + 1) < array_size(req.headers) )
 291                                 {
 292                                         req.headers[hdrcount++] = hdrname;
 293                                         req.headers[hdrcount++] = hdrdata;
 294
 295                                         hdrname = hdrdata = NULL;
 296                                 }
 297
 298                                 /* too large */
 299                                 else
 300                                 {
 301                                         uh_http_response(cl, 413, "Request Entity Too Large");
 302                                         return NULL;
 303                                 }
 304                         }
 305
 306                         /* have name but no value and found a colon, start of value */
 307                         else if( hdrname && !hdrdata && ((i+2) < buflen) &&
 308                                 (buffer[i] == ':') && (buffer[i+1] == ' ')
 309                         ) {
 310                                 buffer[i] = 0;
 311                                 hdrdata = &buffer[i+2];
 312                         }
 313
 314                         /* have no name and found [A-Z], start of name */
 315                         else if( !hdrname && isalpha(buffer[i]) && isupper(buffer[i]) )
 316                         {
 317                                 hdrname = &buffer[i];
 318                         }
 319                 }
 320
 321                 /* valid enough */
 322                 req.redirect_status = 200;
 323                 return &req;
 324         }
 325
 326         /* Malformed request */
 327         uh_http_response(cl, 400, "Bad Request");
 328         return NULL;
 329 }
 330
 331
 332 static struct http_request * uh_http_header_recv(struct client *cl)
 333 {
 334         static char buffer[UH_LIMIT_MSGHEAD];
 335         char *bufptr = &buffer[0];
 336         char *idxptr = NULL;
 337
 338         struct timeval timeout;
 339
 340         fd_set reader;
 341
 342         ssize_t blen = sizeof(buffer)-1;
 343         ssize_t rlen = 0;
 344
 345
 346         memset(buffer, 0, sizeof(buffer));
 347
 348         while( blen > 0 )
 349         {
 350                 FD_ZERO(&reader);
 351                 FD_SET(cl->socket, &reader);
 352
 353                 /* fail after 0.1s */
 354                 timeout.tv_sec  = 0;
 355                 timeout.tv_usec = 100000;
 356
 357                 /* check whether fd is readable */
 358                 if( select(cl->socket + 1, &reader, NULL, NULL, &timeout) > 0 )
 359                 {
 360                         /* receive data */
 361                         rlen = uh_tcp_peek(cl, bufptr, blen);
 362
 363                         if( rlen > 0 )
 364                         {
 365                                 if( (idxptr = strfind(buffer, sizeof(buffer), "\r\n\r\n", 4)) )
 366                                 {
 367                                         blen -= uh_tcp_recv(cl, bufptr, (int)(idxptr - bufptr) + 4);
 368
 369                                         /* header read complete ... */
 370                                         return uh_http_header_parse(cl, buffer, sizeof(buffer) - blen - 1);
 371                                 }
 372                                 else
 373                                 {
 374                                         rlen = uh_tcp_recv(cl, bufptr, rlen);
 375                                         blen -= rlen;
 376                                         bufptr += rlen;
 377                                 }
 378                         }
 379                         else
 380                         {
 381                                 /* invalid request (unexpected eof/timeout) */
 382                                 uh_http_response(cl, 408, "Request Timeout");
 383                                 return NULL;
 384                         }
 385                 }
 386                 else
 387                 {
 388                         /* invalid request (unexpected eof/timeout) */
 389                         uh_http_response(cl, 408, "Request Timeout");
 390                         return NULL;
 391                 }
 392         }
 393
 394         /* request entity too large */
 395         uh_http_response(cl, 413, "Request Entity Too Large");
 396         return NULL;
 397 }
 398
 399 static int uh_path_match(const char *prefix, const char *url)
 400 {
 401         if( (strstr(url, prefix) == url) &&
 402             ((prefix[strlen(prefix)-1] == '/') ||
 403                  (strlen(url) == strlen(prefix))   ||
 404                  (url[strlen(prefix)] == '/'))
 405         ) {
 406                 return 1;
 407         }
 408
 409         return 0;
 410 }
 411
 412
 413 int main (int argc, char **argv)
 414 {
 415 #ifdef HAVE_LUA
 416         /* Lua runtime */
 417         lua_State *L = NULL;
 418 #endif
 419
 420         /* master file descriptor list */
 421         fd_set used_fds, serv_fds, read_fds;
 422
 423         /* working structs */
 424         struct addrinfo hints;
 425         struct http_request *req;
 426         struct path_info *pin;
 427         struct client *cl;
 428         struct sigaction sa;
 429         struct config conf;
 430
 431         /* signal mask */
 432         sigset_t ss;
 433
 434         /* maximum file descriptor number */
 435         int new_fd, cur_fd, max_fd = 0;
 436
 437 #ifdef HAVE_TLS
 438         int tls = 0;
 439         int keys = 0;
 440 #endif
 441
 442         int bound = 0;
 443         int nofork = 0;
 444
 445         /* args */
 446         int opt;
 447         char bind[128];
 448         char *port = NULL;
 449
 450 #if defined(HAVE_TLS) || defined(HAVE_LUA)
 451         /* library handle */
 452         void *lib;
 453 #endif
 454
 455         /* clear the master and temp sets */
 456         FD_ZERO(&used_fds);
 457         FD_ZERO(&serv_fds);
 458         FD_ZERO(&read_fds);
 459
 460         /* handle SIGPIPE, SIGINT, SIGTERM, SIGCHLD */
 461         sa.sa_flags = 0;
 462         sigemptyset(&sa.sa_mask);
 463
 464         sa.sa_handler = SIG_IGN;
 465         sigaction(SIGPIPE, &sa, NULL);
 466
 467         sa.sa_handler = uh_sigchld;
 468         sigaction(SIGCHLD, &sa, NULL);
 469
 470         sa.sa_handler = uh_sigterm;
 471         sigaction(SIGINT,  &sa, NULL);
 472         sigaction(SIGTERM, &sa, NULL);
 473
 474         /* defer SIGCHLD */
 475         sigemptyset(&ss);
 476         sigaddset(&ss, SIGCHLD);
 477         sigprocmask(SIG_BLOCK, &ss, NULL);
 478
 479         /* prepare addrinfo hints */
 480         memset(&hints, 0, sizeof(hints));
 481         hints.ai_family   = AF_UNSPEC;
 482         hints.ai_socktype = SOCK_STREAM;
 483         hints.ai_flags    = AI_PASSIVE;
 484
 485         /* parse args */
 486         memset(&conf, 0, sizeof(conf));
 487         memset(bind, 0, sizeof(bind));
 488
 489 #ifdef HAVE_TLS
 490         /* load TLS plugin */
 491         if( ! (lib = dlopen("uhttpd_tls.so", RTLD_LAZY | RTLD_GLOBAL)) )
 492         {
 493                 fprintf(stderr,
 494                         "Notice: Unable to load TLS plugin - disabling SSL support! "
 495                         "(Reason: %s)\n", dlerror()
 496                 );
 497         }
 498         else
 499         {
 500                 /* resolve functions */
 501                 if( !(conf.tls_init   = dlsym(lib, "uh_tls_ctx_init"))      ||
 502                     !(conf.tls_cert   = dlsym(lib, "uh_tls_ctx_cert"))      ||
 503                     !(conf.tls_key    = dlsym(lib, "uh_tls_ctx_key"))       ||
 504                     !(conf.tls_free   = dlsym(lib, "uh_tls_ctx_free"))      ||
 505                         !(conf.tls_accept = dlsym(lib, "uh_tls_client_accept")) ||
 506                         !(conf.tls_close  = dlsym(lib, "uh_tls_client_close"))  ||
 507                         !(conf.tls_recv   = dlsym(lib, "uh_tls_client_recv"))   ||
 508                         !(conf.tls_send   = dlsym(lib, "uh_tls_client_send"))
 509                 ) {
 510                         fprintf(stderr,
 511                                 "Error: Failed to lookup required symbols "
 512                                 "in TLS plugin: %s\n", dlerror()
 513                         );
 514                         exit(1);
 515                 }
 516
 517                 /* init SSL context */
 518                 if( ! (conf.tls = conf.tls_init()) )
 519                 {
 520                         fprintf(stderr, "Error: Failed to initalize SSL context\n");
 521                         exit(1);
 522                 }
 523         }
 524 #endif
 525
 526         while( (opt = getopt(argc, argv,
 527                 "fSDC:K:E:I:p:s:h:c:l:L:d:r:m:x:t:T:")) > 0
 528         ) {
 529                 switch(opt)
 530                 {
 531                         /* [addr:]port */
 532                         case 'p':
 533                         case 's':
 534                                 if( (port = strrchr(optarg, ':')) != NULL )
 535                                 {
 536                                         if( (optarg[0] == '[') && (port > optarg) && (port[-1] == ']') )
 537                                                 memcpy(bind, optarg + 1,
 538                                                         min(sizeof(bind), (int)(port - optarg) - 2));
 539                                         else
 540                                                 memcpy(bind, optarg,
 541                                                         min(sizeof(bind), (int)(port - optarg)));
 542
 543                                         port++;
 544                                 }
 545                                 else
 546                                 {
 547                                         port = optarg;
 548                                 }
 549
 550 #ifdef HAVE_TLS
 551                                 if( opt == 's' )
 552                                 {
 553                                         if( !conf.tls )
 554                                         {
 555                                                 fprintf(stderr,
 556                                                         "Notice: TLS support is disabled, "
 557                                                         "ignoring '-s %s'\n", optarg
 558                                                 );
 559                                                 continue;
 560                                         }
 561
 562                                         tls = 1;
 563                                 }
 564 #endif
 565
 566                                 /* bind sockets */
 567                                 bound += uh_socket_bind(
 568                                         &serv_fds, &max_fd, bind[0] ? bind : NULL, port,
 569                                         &hints, (opt == 's'), &conf
 570                                 );
 571
 572                                 memset(bind, 0, sizeof(bind));
 573                                 break;
 574
 575 #ifdef HAVE_TLS
 576                         /* certificate */
 577                         case 'C':
 578                                 if( conf.tls )
 579                                 {
 580                                         if( conf.tls_cert(conf.tls, optarg) < 1 )
 581                                         {
 582                                                 fprintf(stderr,
 583                                                         "Error: Invalid certificate file given\n");
 584                                                 exit(1);
 585                                         }
 586
 587                                         keys++;
 588                                 }
 589
 590                                 break;
 591
 592                         /* key */
 593                         case 'K':
 594                                 if( conf.tls )
 595                                 {
 596                                         if( conf.tls_key(conf.tls, optarg) < 1 )
 597                                         {
 598                                                 fprintf(stderr,
 599                                                         "Error: Invalid private key file given\n");
 600                                                 exit(1);
 601                                         }
 602
 603                                         keys++;
 604                                 }
 605
 606                                 break;
 607 #endif
 608
 609                         /* docroot */
 610                         case 'h':
 611                                 if( ! realpath(optarg, conf.docroot) )
 612                                 {
 613                                         fprintf(stderr, "Error: Invalid directory %s: %s\n",
 614                                                 optarg, strerror(errno));
 615                                         exit(1);
 616                                 }
 617                                 break;
 618
 619                         /* error handler */
 620                         case 'E':
 621                                 if( (strlen(optarg) == 0) || (optarg[0] != '/') )
 622                                 {
 623                                         fprintf(stderr, "Error: Invalid error handler: %s\n",
 624                                                 optarg);
 625                                         exit(1);
 626                                 }
 627                                 conf.error_handler = optarg;
 628                                 break;
 629
 630                         /* index file */
 631                         case 'I':
 632                                 if( (strlen(optarg) == 0) || (optarg[0] == '/') )
 633                                 {
 634                                         fprintf(stderr, "Error: Invalid index page: %s\n",
 635                                                 optarg);
 636                                         exit(1);
 637                                 }
 638                                 conf.index_file = optarg;
 639                                 break;
 640
 641                         /* don't follow symlinks */
 642                         case 'S':
 643                                 conf.no_symlinks = 1;
 644                                 break;
 645
 646                         /* don't list directories */
 647                         case 'D':
 648                                 conf.no_dirlists = 1;
 649                                 break;
 650
 651 #ifdef HAVE_CGI
 652                         /* cgi prefix */
 653                         case 'x':
 654                                 conf.cgi_prefix = optarg;
 655                                 break;
 656 #endif
 657
 658 #ifdef HAVE_LUA
 659                         /* lua prefix */
 660                         case 'l':
 661                                 conf.lua_prefix = optarg;
 662                                 break;
 663
 664                         /* lua handler */
 665                         case 'L':
 666                                 conf.lua_handler = optarg;
 667                                 break;
 668 #endif
 669
 670 #if defined(HAVE_CGI) || defined(HAVE_LUA)
 671                         /* script timeout */
 672                         case 't':
 673                                 conf.script_timeout = atoi(optarg);
 674                                 break;
 675 #endif
 676
 677                         /* network timeout */
 678                         case 'T':
 679                                 conf.network_timeout = atoi(optarg);
 680                                 break;
 681
 682                         /* no fork */
 683                         case 'f':
 684                                 nofork = 1;
 685                                 break;
 686
 687                         /* urldecode */
 688                         case 'd':
 689                                 if( (port = malloc(strlen(optarg)+1)) != NULL )
 690                                 {
 691                                         memset(port, 0, strlen(optarg)+1);
 692                                         uh_urldecode(port, strlen(optarg), optarg, strlen(optarg));
 693                                         printf("%s", port);
 694                                         free(port);
 695                                         exit(0);
 696                                 }
 697                                 break;
 698
 699                         /* basic auth realm */
 700                         case 'r':
 701                                 conf.realm = optarg;
 702                                 break;
 703
 704                         /* md5 crypt */
 705                         case 'm':
 706                                 printf("%s\n", crypt(optarg, "$1$"));
 707                                 exit(0);
 708                                 break;
 709
 710                         /* config file */
 711                         case 'c':
 712                                 conf.file = optarg;
 713                                 break;
 714
 715                         default:
 716                                 fprintf(stderr,
 717                                         "Usage: %s -p [addr:]port [-h docroot]\n"
 718                                         "       -f              Do not fork to background\n"
 719                                         "       -c file         Configuration file, default is '/etc/httpd.conf'\n"
 720                                         "       -p [addr:]port  Bind to specified address and port, multiple allowed\n"
 721 #ifdef HAVE_TLS
 722                                         "       -s [addr:]port  Like -p but provide HTTPS on this port\n"
 723                                         "       -C file         ASN.1 server certificate file\n"
 724                                         "       -K file         ASN.1 server private key file\n"
 725 #endif
 726                                         "       -h directory    Specify the document root, default is '.'\n"
 727                                         "       -E string       Use given virtual URL as 404 error handler\n"
 728                                         "       -I string       Use given filename as index page for directories\n"
 729                                         "       -S              Do not follow symbolic links outside of the docroot\n"
 730                                         "       -D              Do not allow directory listings, send 403 instead\n"
 731 #ifdef HAVE_LUA
 732                                         "       -l string       URL prefix for Lua handler, default is '/lua'\n"
 733                                         "       -L file         Lua handler script, omit to disable Lua\n"
 734 #endif
 735 #ifdef HAVE_CGI
 736                                         "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 737 #endif
 738 #if defined(HAVE_CGI) || defined(HAVE_LUA)
 739                                         "       -t seconds      CGI and Lua script timeout in seconds, default is 60\n"
 740 #endif
 741                                         "       -T seconds      Network timeout in seconds, default is 30\n"
 742                                         "       -d string       URL decode given string\n"
 743                                         "       -r string       Specify basic auth realm\n"
 744                                         "       -m string       MD5 crypt given string\n"
 745                                         "\n", argv[0]
 746                                 );
 747
 748                                 exit(1);
 749                 }
 750         }
 751
 752 #ifdef HAVE_TLS
 753         if( (tls == 1) && (keys < 2) )
 754         {
 755                 fprintf(stderr, "Error: Missing private key or certificate file\n");
 756                 exit(1);
 757         }
 758 #endif
 759
 760         if( bound < 1 )
 761         {
 762                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 763                 exit(1);
 764         }
 765
 766         /* default docroot */
 767         if( !conf.docroot[0] && !realpath(".", conf.docroot) )
 768         {
 769                 fprintf(stderr, "Error: Can not determine default document root: %s\n",
 770                         strerror(errno));
 771                 exit(1);
 772         }
 773
 774         /* default realm */
 775         if( ! conf.realm )
 776                 conf.realm = "Protected Area";
 777
 778         /* config file */
 779         uh_config_parse(&conf);
 780
 781         /* default network timeout */
 782         if( conf.network_timeout <= 0 )
 783                 conf.network_timeout = 30;
 784
 785 #if defined(HAVE_CGI) || defined(HAVE_LUA)
 786         /* default script timeout */
 787         if( conf.script_timeout <= 0 )
 788                 conf.script_timeout = 60;
 789 #endif
 790
 791 #ifdef HAVE_CGI
 792         /* default cgi prefix */
 793         if( ! conf.cgi_prefix )
 794                 conf.cgi_prefix = "/cgi-bin";
 795 #endif
 796
 797 #ifdef HAVE_LUA
 798         /* load Lua plugin */
 799         if( ! (lib = dlopen("uhttpd_lua.so", RTLD_LAZY | RTLD_GLOBAL)) )
 800         {
 801                 fprintf(stderr,
 802                         "Notice: Unable to load Lua plugin - disabling Lua support! "
 803                         "(Reason: %s)\n", dlerror()
 804                 );
 805         }
 806         else
 807         {
 808                 /* resolve functions */
 809                 if( !(conf.lua_init    = dlsym(lib, "uh_lua_init"))    ||
 810                     !(conf.lua_close   = dlsym(lib, "uh_lua_close"))   ||
 811                     !(conf.lua_request = dlsym(lib, "uh_lua_request"))
 812                 ) {
 813                         fprintf(stderr,
 814                                 "Error: Failed to lookup required symbols "
 815                                 "in Lua plugin: %s\n", dlerror()
 816                         );
 817                         exit(1);
 818                 }
 819
 820                 /* init Lua runtime if handler is specified */
 821                 if( conf.lua_handler )
 822                 {
 823                         /* default lua prefix */
 824                         if( ! conf.lua_prefix )
 825                                 conf.lua_prefix = "/lua";
 826
 827                         L = conf.lua_init(conf.lua_handler);
 828                 }
 829         }
 830 #endif
 831
 832         /* fork (if not disabled) */
 833         if( ! nofork )
 834         {
 835                 switch( fork() )
 836                 {
 837                         case -1:
 838                                 perror("fork()");
 839                                 exit(1);
 840
 841                         case 0:
 842                                 /* daemon setup */
 843                                 if( chdir("/") )
 844                                         perror("chdir()");
 845
 846                                 if( (cur_fd = open("/dev/null", O_WRONLY)) > -1 )
 847                                         dup2(cur_fd, 0);
 848
 849                                 if( (cur_fd = open("/dev/null", O_RDONLY)) > -1 )
 850                                         dup2(cur_fd, 1);
 851
 852                                 if( (cur_fd = open("/dev/null", O_RDONLY)) > -1 )
 853                                         dup2(cur_fd, 2);
 854
 855                                 break;
 856
 857                         default:
 858                                 exit(0);
 859                 }
 860         }
 861
 862         /* backup server descriptor set */
 863         used_fds = serv_fds;
 864
 865         /* loop */
 866         while(run)
 867         {
 868                 /* create a working copy of the used fd set */
 869                 read_fds = used_fds;
 870
 871                 /* sleep until socket activity */
 872                 if( select(max_fd + 1, &read_fds, NULL, NULL, NULL) == -1 )
 873                 {
 874                         perror("select()");
 875                         exit(1);
 876                 }
 877
 878                 /* run through the existing connections looking for data to be read */
 879                 for( cur_fd = 0; cur_fd <= max_fd; cur_fd++ )
 880                 {
 881                         /* is a socket managed by us */
 882                         if( FD_ISSET(cur_fd, &read_fds) )
 883                         {
 884                                 /* is one of our listen sockets */
 885                                 if( FD_ISSET(cur_fd, &serv_fds) )
 886                                 {
 887                                         /* handle new connections */
 888                                         if( (new_fd = accept(cur_fd, NULL, 0)) != -1 )
 889                                         {
 890                                                 /* add to global client list */
 891                                                 if( (cl = uh_client_add(new_fd, uh_listener_lookup(cur_fd))) != NULL )
 892                                                 {
 893 #ifdef HAVE_TLS
 894                                                         /* setup client tls context */
 895                                                         if( conf.tls )
 896                                                                 conf.tls_accept(cl);
 897 #endif
 898
 899                                                         /* add client socket to global fdset */
 900                                                         FD_SET(new_fd, &used_fds);
 901                                                         fd_cloexec(new_fd);
 902                                                         max_fd = max(max_fd, new_fd);
 903                                                 }
 904
 905                                                 /* insufficient resources */
 906                                                 else
 907                                                 {
 908                                                         fprintf(stderr,
 909                                                                 "uh_client_add(): Can not manage more than "
 910                                                                 "%i client sockets, connection dropped\n",
 911                                                                 UH_LIMIT_CLIENTS
 912                                                         );
 913
 914                                                         close(new_fd);
 915                                                 }
 916                                         }
 917                                 }
 918
 919                                 /* is a client socket */
 920                                 else
 921                                 {
 922                                         if( ! (cl = uh_client_lookup(cur_fd)) )
 923                                         {
 924                                                 /* this should not happen! */
 925                                                 fprintf(stderr,
 926                                                         "uh_client_lookup(): No entry for fd %i!\n",
 927                                                         cur_fd);
 928
 929                                                 goto cleanup;
 930                                         }
 931
 932                                         /* parse message header */
 933                                         if( (req = uh_http_header_recv(cl)) != NULL )
 934                                         {
 935 #ifdef HAVE_LUA
 936                                                 /* Lua request? */
 937                                                 if( L && uh_path_match(conf.lua_prefix, req->url) )
 938                                                 {
 939                                                         conf.lua_request(cl, req, L);
 940                                                 }
 941                                                 else
 942 #endif
 943                                                 /* dispatch request */
 944                                                 if( (pin = uh_path_lookup(cl, req->url)) != NULL )
 945                                                 {
 946                                                         /* auth ok? */
 947                                                         if( uh_auth_check(cl, req, pin) )
 948                                                         {
 949 #ifdef HAVE_CGI
 950                                                                 if( uh_path_match(conf.cgi_prefix, pin->name) )
 951                                                                 {
 952                                                                         uh_cgi_request(cl, req, pin);
 953                                                                 }
 954                                                                 else
 955 #endif
 956                                                                 {
 957                                                                         uh_file_request(cl, req, pin);
 958                                                                 }
 959                                                         }
 960                                                 }
 961
 962                                                 /* 404 */
 963                                                 else
 964                                                 {
 965                                                         /* Try to invoke an error handler */
 966                                                         pin = uh_path_lookup(cl, conf.error_handler);
 967
 968                                                         if( pin && uh_auth_check(cl, req, pin) )
 969                                                         {
 970                                                                 req->redirect_status = 404;
 971
 972 #ifdef HAVE_CGI
 973                                                                 if( uh_path_match(conf.cgi_prefix, pin->name) )
 974                                                                 {
 975                                                                         uh_cgi_request(cl, req, pin);
 976                                                                 }
 977                                                                 else
 978 #endif
 979                                                                 {
 980                                                                         uh_file_request(cl, req, pin);
 981                                                                 }
 982                                                         }
 983                                                         else
 984                                                         {
 985                                                                 uh_http_sendhf(cl, 404, "Not Found",
 986                                                                         "No such file or directory");
 987                                                         }
 988                                                 }
 989                                         }
 990
 991                                         /* 400 */
 992                                         else
 993                                         {
 994                                                 uh_http_sendhf(cl, 400, "Bad Request",
 995                                                         "Malformed request received");
 996                                         }
 997
 998 #ifdef HAVE_TLS
 999                                         /* free client tls context */
1000                                         if( conf.tls )
1001                                                 conf.tls_close(cl);
1002 #endif
1003
1004                                         cleanup:
1005
1006                                         /* close client socket */
1007                                         close(cur_fd);
1008                                         FD_CLR(cur_fd, &used_fds);
1009
1010                                         /* remove from global client list */
1011                                         uh_client_remove(cur_fd);
1012                                 }
1013                         }
1014                 }
1015         }
1016
1017 #ifdef HAVE_LUA
1018         /* destroy the Lua state */
1019         if( L != NULL )
1020                 conf.lua_close(L);
1021 #endif
1022
1023         return 0;
1024 }
1025