main.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd
   3  *
   4  *   Copyright (C) 2010-2013 Jo-Philipp Wich <xm@subsignal.org>
   5  *   Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 #ifndef _DEFAULT_SOURCE
  21 # define _DEFAULT_SOURCE
  22 #endif
  23
  24 #define _BSD_SOURCE
  25 #define _GNU_SOURCE
  26 #define _XOPEN_SOURCE   700
  27 #include <sys/types.h>
  28 #include <sys/socket.h>
  29 #include <netinet/in.h>
  30
  31 #include <getopt.h>
  32 #include <errno.h>
  33 #include <netdb.h>
  34 #include <signal.h>
  35
  36 #include <libubox/usock.h>
  37 #include <libubox/utils.h>
  38
  39 #include "uhttpd.h"
  40 #include "tls.h"
  41
  42 char uh_buf[4096];
  43
  44 static int run_server(void)
  45 {
  46         uloop_init();
  47         uh_setup_listeners();
  48         uh_plugin_post_init();
  49         uloop_run();
  50
  51         return 0;
  52 }
  53
  54 static void uh_config_parse(void)
  55 {
  56         const char *path = conf.file;
  57         FILE *c;
  58         char line[512];
  59         char *col1;
  60         char *col2;
  61         char *eol;
  62
  63         if (!path)
  64                 path = "/etc/httpd.conf";
  65
  66         c = fopen(path, "r");
  67         if (!c)
  68                 return;
  69
  70         memset(line, 0, sizeof(line));
  71
  72         while (fgets(line, sizeof(line) - 1, c)) {
  73                 if ((line[0] == '/') && (strchr(line, ':') != NULL)) {
  74                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  75                                 !(col2 = strchr(col1, ':')) || (*col2++ = 0) ||
  76                                 !(eol = strchr(col2, '\n')) || (*eol++  = 0))
  77                                 continue;
  78
  79                         uh_auth_add(line, col1, col2);
  80                 } else if (!strncmp(line, "I:", 2)) {
  81                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  82                                 !(eol = strchr(col1, '\n')) || (*eol++  = 0))
  83                                 continue;
  84
  85                         uh_index_add(strdup(col1));
  86                 } else if (!strncmp(line, "E404:", 5)) {
  87                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  88                                 !(eol = strchr(col1, '\n')) || (*eol++  = 0))
  89                                 continue;
  90
  91                         conf.error_handler = strdup(col1);
  92                 }
  93                 else if ((line[0] == '*') && (strchr(line, ':') != NULL)) {
  94                         if (!(col1 = strchr(line, '*')) || (*col1++ = 0) ||
  95                                 !(col2 = strchr(col1, ':')) || (*col2++ = 0) ||
  96                                 !(eol = strchr(col2, '\n')) || (*eol++  = 0))
  97                                 continue;
  98
  99                         uh_interpreter_add(col1, col2);
 100                 }
 101         }
 102
 103         fclose(c);
 104 }
 105
 106 static int add_listener_arg(char *arg, bool tls)
 107 {
 108         char *host = NULL;
 109         char *port = arg;
 110         char *s;
 111         int l;
 112
 113         s = strrchr(arg, ':');
 114         if (s) {
 115                 host = arg;
 116                 port = s + 1;
 117                 *s = 0;
 118         }
 119
 120         if (host && *host == '[') {
 121                 l = strlen(host);
 122                 if (l >= 2) {
 123                         host[l-1] = 0;
 124                         host++;
 125                 }
 126         }
 127
 128         return uh_socket_bind(host, port, tls);
 129 }
 130
 131 static int usage(const char *name)
 132 {
 133         fprintf(stderr,
 134                 "Usage: %s -p [addr:]port -h docroot\n"
 135                 "       -f              Do not fork to background\n"
 136                 "       -c file         Configuration file, default is '/etc/httpd.conf'\n"
 137                 "       -p [addr:]port  Bind to specified address and port, multiple allowed\n"
 138 #ifdef HAVE_TLS
 139                 "       -s [addr:]port  Like -p but provide HTTPS on this port\n"
 140                 "       -C file         ASN.1 server certificate file\n"
 141                 "       -K file         ASN.1 server private key file\n"
 142                 "       -P ciphers      Colon separated list of allowed TLS ciphers\n"
 143                 "       -q              Redirect all HTTP requests to HTTPS\n"
 144 #endif
 145                 "       -h directory    Specify the document root, default is '.'\n"
 146                 "       -E string       Use given virtual URL as 404 error handler\n"
 147                 "       -I string       Use given filename as index for directories, multiple allowed\n"
 148                 "       -S              Do not follow symbolic links outside of the docroot\n"
 149                 "       -D              Do not allow directory listings, send 403 instead\n"
 150                 "       -R              Enable RFC1918 filter\n"
 151                 "       -n count        Maximum allowed number of concurrent script requests\n"
 152                 "       -N count        Maximum allowed number of concurrent connections\n"
 153 #ifdef HAVE_LUA
 154                 "       -l string       URL prefix for Lua handler, default is '/lua'\n"
 155                 "       -L file         Lua handler script, omit to disable Lua\n"
 156 #endif
 157 #ifdef HAVE_UBUS
 158                 "       -u string       URL prefix for UBUS via JSON-RPC handler\n"
 159                 "       -U file         Override ubus socket path\n"
 160                 "       -a              Do not authenticate JSON-RPC requests against UBUS session api\n"
 161                 "       -X              Enable CORS HTTP headers on JSON-RPC api\n"
 162                 "       -e              Events subscription reconnection time (retry value)\n"
 163 #endif
 164                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 165                 "       -y alias[=path] URL alias handle\n"
 166                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 167                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 168                 "       -T seconds      Network timeout in seconds, default is 30\n"
 169                 "       -k seconds      HTTP keepalive timeout\n"
 170                 "       -A seconds      TCP keepalive timeout, default is unset\n"
 171                 "       -d string       URL decode given string\n"
 172                 "       -r string       Specify basic auth realm\n"
 173                 "       -m string       MD5 crypt given string\n"
 174                 "\n", name
 175         );
 176         return 1;
 177 }
 178
 179 static void init_defaults_pre(void)
 180 {
 181         conf.script_timeout = 60;
 182         conf.network_timeout = 30;
 183         conf.http_keepalive = 20;
 184         conf.max_script_requests = 3;
 185         conf.max_connections = 100;
 186         conf.realm = "Protected Area";
 187         conf.cgi_prefix = "/cgi-bin";
 188         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 189         INIT_LIST_HEAD(&conf.cgi_alias);
 190         INIT_LIST_HEAD(&conf.lua_prefix);
 191 }
 192
 193 static void init_defaults_post(void)
 194 {
 195         uh_index_add("index.html");
 196         uh_index_add("index.htm");
 197         uh_index_add("default.html");
 198         uh_index_add("default.htm");
 199
 200         if (conf.cgi_prefix) {
 201                 char *str = malloc(strlen(conf.docroot) + strlen(conf.cgi_prefix) + 1);
 202
 203                 strcpy(str, conf.docroot);
 204                 strcat(str, conf.cgi_prefix);
 205                 conf.cgi_docroot_path = str;
 206                 conf.cgi_prefix_len = strlen(conf.cgi_prefix);
 207         };
 208 }
 209
 210 static void fixup_prefix(char *str)
 211 {
 212         int len;
 213
 214         if (!str || !str[0])
 215                 return;
 216
 217         len = strlen(str) - 1;
 218
 219         while (len >= 0 && str[len] == '/')
 220                 len--;
 221
 222         str[len + 1] = 0;
 223 }
 224
 225 #ifdef HAVE_LUA
 226 static void add_lua_prefix(const char *prefix, const char *handler) {
 227         struct lua_prefix *p;
 228         char *pprefix, *phandler;
 229
 230         p = calloc_a(sizeof(*p),
 231                      &pprefix, strlen(prefix) + 1,
 232                      &phandler, strlen(handler) + 1);
 233
 234         if (!p)
 235                 return;
 236
 237         p->prefix = strcpy(pprefix, prefix);
 238         p->handler = strcpy(phandler, handler);
 239
 240         list_add_tail(&p->list, &conf.lua_prefix);
 241 }
 242 #endif
 243
 244 int main(int argc, char **argv)
 245 {
 246         struct alias *alias;
 247         bool nofork = false;
 248         char *port;
 249         int opt, ch;
 250         int cur_fd;
 251         int bound = 0;
 252 #ifdef HAVE_TLS
 253         int n_tls = 0;
 254         const char *tls_key = NULL, *tls_crt = NULL, *tls_ciphers = NULL;
 255 #endif
 256 #ifdef HAVE_LUA
 257         const char *lua_prefix = NULL, *lua_handler = NULL;
 258 #endif
 259
 260         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 261
 262         uh_dispatch_add(&cgi_dispatch);
 263         init_defaults_pre();
 264         signal(SIGPIPE, SIG_IGN);
 265
 266         while ((ch = getopt(argc, argv, "A:aC:c:Dd:E:e:fh:H:I:i:K:k:L:l:m:N:n:P:p:qRr:Ss:T:t:U:u:Xx:y:")) != -1) {
 267                 switch(ch) {
 268 #ifdef HAVE_TLS
 269                 case 'C':
 270                         tls_crt = optarg;
 271                         break;
 272
 273                 case 'K':
 274                         tls_key = optarg;
 275                         break;
 276
 277                 case 'P':
 278                         tls_ciphers = optarg;
 279                         break;
 280
 281                 case 'q':
 282                         conf.tls_redirect = 1;
 283                         break;
 284
 285                 case 's':
 286                         n_tls++;
 287                         /* fall through */
 288 #else
 289                 case 'C':
 290                 case 'K':
 291                 case 'P':
 292                 case 'q':
 293                 case 's':
 294                         fprintf(stderr, "uhttpd: TLS support not compiled, "
 295                                         "ignoring -%c\n", ch);
 296                         break;
 297 #endif
 298                 case 'p':
 299                         optarg = strdup(optarg);
 300                         bound += add_listener_arg(optarg, (ch == 's'));
 301                         break;
 302
 303                 case 'h':
 304                         if (!realpath(optarg, uh_buf)) {
 305                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 306                                                 optarg, strerror(errno));
 307                                 exit(1);
 308                         }
 309                         conf.docroot = strdup(uh_buf);
 310                         break;
 311
 312                 case 'H':
 313                         if (uh_handler_add(optarg)) {
 314                                 fprintf(stderr, "Error: Failed to load handler script %s\n",
 315                                         optarg);
 316                                 exit(1);
 317                         }
 318                         break;
 319
 320                 case 'E':
 321                         if (optarg[0] != '/') {
 322                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 323                                                 optarg);
 324                                 exit(1);
 325                         }
 326                         conf.error_handler = optarg;
 327                         break;
 328
 329                 case 'I':
 330                         if (optarg[0] == '/') {
 331                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 332                                                 optarg);
 333                                 exit(1);
 334                         }
 335                         uh_index_add(optarg);
 336                         break;
 337
 338                 case 'S':
 339                         conf.no_symlinks = 1;
 340                         break;
 341
 342                 case 'D':
 343                         conf.no_dirlists = 1;
 344                         break;
 345
 346                 case 'R':
 347                         conf.rfc1918_filter = 1;
 348                         break;
 349
 350                 case 'n':
 351                         conf.max_script_requests = atoi(optarg);
 352                         break;
 353
 354                 case 'N':
 355                         conf.max_connections = atoi(optarg);
 356                         break;
 357
 358                 case 'x':
 359                         fixup_prefix(optarg);
 360                         conf.cgi_prefix = optarg;
 361                         break;
 362
 363                 case 'y':
 364                         alias = calloc(1, sizeof(*alias));
 365                         if (!alias) {
 366                                 fprintf(stderr, "Error: failed to allocate alias\n");
 367                                 exit(1);
 368                         }
 369                         alias->alias = strdup(optarg);
 370                         alias->path = strchr(alias->alias, '=');
 371                         if (alias->path)
 372                                 *alias->path++ = 0;
 373                         list_add(&alias->list, &conf.cgi_alias);
 374                         break;
 375
 376                 case 'i':
 377                         optarg = strdup(optarg);
 378                         port = strchr(optarg, '=');
 379                         if (optarg[0] != '.' || !port) {
 380                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 381                                                 optarg);
 382                                 exit(1);
 383                         }
 384
 385                         *port++ = 0;
 386                         uh_interpreter_add(optarg, port);
 387                         break;
 388
 389                 case 't':
 390                         conf.script_timeout = atoi(optarg);
 391                         break;
 392
 393                 case 'T':
 394                         conf.network_timeout = atoi(optarg);
 395                         break;
 396
 397                 case 'k':
 398                         conf.http_keepalive = atoi(optarg);
 399                         break;
 400
 401                 case 'A':
 402                         conf.tcp_keepalive = atoi(optarg);
 403                         break;
 404
 405                 case 'f':
 406                         nofork = 1;
 407                         break;
 408
 409                 case 'd':
 410                         optarg = strdup(optarg);
 411                         port = alloca(strlen(optarg) + 1);
 412                         if (!port)
 413                                 return -1;
 414
 415                         /* "decode" plus to space to retain compat */
 416                         for (opt = 0; optarg[opt]; opt++)
 417                                 if (optarg[opt] == '+')
 418                                         optarg[opt] = ' ';
 419
 420                         /* opt now contains strlen(optarg) -- no need to re-scan */
 421                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 422                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 423                                 return -1;
 424                         }
 425
 426                         printf("%s", port);
 427                         return 0;
 428                         break;
 429
 430                 /* basic auth realm */
 431                 case 'r':
 432                         conf.realm = optarg;
 433                         break;
 434
 435                 /* md5 crypt */
 436                 case 'm':
 437                         printf("%s\n", crypt(optarg, "$1$"));
 438                         return 0;
 439                         break;
 440
 441                 /* config file */
 442                 case 'c':
 443                         conf.file = optarg;
 444                         break;
 445
 446 #ifdef HAVE_LUA
 447                 case 'l':
 448                 case 'L':
 449                         if (ch == 'l') {
 450                                 if (lua_prefix)
 451                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 452                                                 ch, lua_prefix);
 453
 454                                 lua_prefix = optarg;
 455                         }
 456                         else {
 457                                 if (lua_handler)
 458                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 459                                                 ch, lua_handler);
 460
 461                                 lua_handler = optarg;
 462                         }
 463
 464                         if (lua_prefix && lua_handler) {
 465                                 add_lua_prefix(lua_prefix, lua_handler);
 466                                 lua_prefix = NULL;
 467                                 lua_handler = NULL;
 468                         }
 469
 470                         break;
 471 #else
 472                 case 'l':
 473                 case 'L':
 474                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 475                                         "ignoring -%c\n", ch);
 476                         break;
 477 #endif
 478 #ifdef HAVE_UBUS
 479                 case 'a':
 480                         conf.ubus_noauth = 1;
 481                         break;
 482
 483                 case 'u':
 484                         conf.ubus_prefix = optarg;
 485                         break;
 486
 487                 case 'U':
 488                         conf.ubus_socket = optarg;
 489                         break;
 490
 491                 case 'X':
 492                         conf.ubus_cors = 1;
 493                         break;
 494
 495                 case 'e':
 496                         conf.events_retry = atoi(optarg);
 497                         break;
 498 #else
 499                 case 'a':
 500                 case 'u':
 501                 case 'U':
 502                 case 'X':
 503                 case 'e':
 504                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 505                                         "ignoring -%c\n", ch);
 506                         break;
 507 #endif
 508                 default:
 509                         return usage(argv[0]);
 510                 }
 511         }
 512
 513         uh_config_parse();
 514
 515         if (!conf.docroot) {
 516                 if (!realpath(".", uh_buf)) {
 517                         fprintf(stderr, "Error: Unable to determine work dir\n");
 518                         return 1;
 519                 }
 520                 conf.docroot = strdup(uh_buf);
 521         }
 522
 523         init_defaults_post();
 524
 525         if (!bound) {
 526                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 527                 return 1;
 528         }
 529
 530 #ifdef HAVE_TLS
 531         if (n_tls) {
 532                 if (!tls_crt || !tls_key) {
 533                         fprintf(stderr, "Please specify a certificate and "
 534                                         "a key file to enable SSL support\n");
 535                         return 1;
 536                 }
 537
 538                 if (uh_tls_init(tls_key, tls_crt, tls_ciphers))
 539                     return 1;
 540         }
 541 #endif
 542
 543 #ifdef HAVE_LUA
 544         if (lua_handler || lua_prefix) {
 545                 fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 546                 return 1;
 547         }
 548
 549         if (!list_empty(&conf.lua_prefix) && uh_plugin_init("uhttpd_lua.so"))
 550                 return 1;
 551 #endif
 552 #ifdef HAVE_UBUS
 553         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 554                 return 1;
 555 #endif
 556
 557         /* fork (if not disabled) */
 558         if (!nofork) {
 559                 switch (fork()) {
 560                 case -1:
 561                         perror("fork()");
 562                         exit(1);
 563
 564                 case 0:
 565                         /* daemon setup */
 566                         if (chdir("/"))
 567                                 perror("chdir()");
 568
 569                         cur_fd = open("/dev/null", O_WRONLY);
 570                         if (cur_fd > 0) {
 571                                 dup2(cur_fd, 0);
 572                                 dup2(cur_fd, 1);
 573                                 dup2(cur_fd, 2);
 574                         }
 575
 576                         break;
 577
 578                 default:
 579                         exit(0);
 580                 }
 581         }
 582
 583         return run_server();
 584 }