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                 "       -q              Redirect all HTTP requests to HTTPS\n"
 143 #endif
 144                 "       -h directory    Specify the document root, default is '.'\n"
 145                 "       -E string       Use given virtual URL as 404 error handler\n"
 146                 "       -I string       Use given filename as index for directories, multiple allowed\n"
 147                 "       -S              Do not follow symbolic links outside of the docroot\n"
 148                 "       -D              Do not allow directory listings, send 403 instead\n"
 149                 "       -R              Enable RFC1918 filter\n"
 150                 "       -n count        Maximum allowed number of concurrent script requests\n"
 151                 "       -N count        Maximum allowed number of concurrent connections\n"
 152 #ifdef HAVE_LUA
 153                 "       -l string       URL prefix for Lua handler, default is '/lua'\n"
 154                 "       -L file         Lua handler script, omit to disable Lua\n"
 155 #endif
 156 #ifdef HAVE_UBUS
 157                 "       -u string       URL prefix for UBUS via JSON-RPC handler\n"
 158                 "       -U file         Override ubus socket path\n"
 159                 "       -a              Do not authenticate JSON-RPC requests against UBUS session api\n"
 160                 "       -X              Enable CORS HTTP headers on JSON-RPC api\n"
 161 #endif
 162                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 163                 "       -y alias[=path] URL alias handle\n"
 164                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 165                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 166                 "       -T seconds      Network timeout in seconds, default is 30\n"
 167                 "       -k seconds      HTTP keepalive timeout\n"
 168                 "       -A seconds      TCP keepalive timeout, default is unset\n"
 169                 "       -d string       URL decode given string\n"
 170                 "       -r string       Specify basic auth realm\n"
 171                 "       -m string       MD5 crypt given string\n"
 172                 "\n", name
 173         );
 174         return 1;
 175 }
 176
 177 static void init_defaults_pre(void)
 178 {
 179         conf.script_timeout = 60;
 180         conf.network_timeout = 30;
 181         conf.http_keepalive = 20;
 182         conf.max_script_requests = 3;
 183         conf.max_connections = 100;
 184         conf.realm = "Protected Area";
 185         conf.cgi_prefix = "/cgi-bin";
 186         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 187         INIT_LIST_HEAD(&conf.cgi_alias);
 188         INIT_LIST_HEAD(&conf.lua_prefix);
 189 }
 190
 191 static void init_defaults_post(void)
 192 {
 193         uh_index_add("index.html");
 194         uh_index_add("index.htm");
 195         uh_index_add("default.html");
 196         uh_index_add("default.htm");
 197
 198         if (conf.cgi_prefix) {
 199                 char *str = malloc(strlen(conf.docroot) + strlen(conf.cgi_prefix) + 1);
 200
 201                 strcpy(str, conf.docroot);
 202                 strcat(str, conf.cgi_prefix);
 203                 conf.cgi_docroot_path = str;
 204                 conf.cgi_prefix_len = strlen(conf.cgi_prefix);
 205         };
 206 }
 207
 208 static void fixup_prefix(char *str)
 209 {
 210         int len;
 211
 212         if (!str || !str[0])
 213                 return;
 214
 215         len = strlen(str) - 1;
 216
 217         while (len >= 0 && str[len] == '/')
 218                 len--;
 219
 220         str[len + 1] = 0;
 221 }
 222
 223 #ifdef HAVE_LUA
 224 static void add_lua_prefix(const char *prefix, const char *handler) {
 225         struct lua_prefix *p;
 226         char *pprefix, *phandler;
 227
 228         p = calloc_a(sizeof(*p),
 229                      &pprefix, strlen(prefix) + 1,
 230                      &phandler, strlen(handler) + 1);
 231
 232         if (!p)
 233                 return;
 234
 235         p->prefix = strcpy(pprefix, prefix);
 236         p->handler = strcpy(phandler, handler);
 237
 238         list_add_tail(&p->list, &conf.lua_prefix);
 239 }
 240 #endif
 241
 242 int main(int argc, char **argv)
 243 {
 244         struct alias *alias;
 245         bool nofork = false;
 246         char *port;
 247         int opt, ch;
 248         int cur_fd;
 249         int bound = 0;
 250 #ifdef HAVE_TLS
 251         int n_tls = 0;
 252         const char *tls_key = NULL, *tls_crt = NULL;
 253 #endif
 254 #ifdef HAVE_LUA
 255         const char *lua_prefix = NULL, *lua_handler = NULL;
 256 #endif
 257
 258         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 259
 260         uh_dispatch_add(&cgi_dispatch);
 261         init_defaults_pre();
 262         signal(SIGPIPE, SIG_IGN);
 263
 264         while ((ch = getopt(argc, argv, "A:aC:c:Dd:E:fh:H:I:i:K:k:L:l:m:N:n:p:qRr:Ss:T:t:U:u:Xx:y:")) != -1) {
 265                 switch(ch) {
 266 #ifdef HAVE_TLS
 267                 case 'C':
 268                         tls_crt = optarg;
 269                         break;
 270
 271                 case 'K':
 272                         tls_key = optarg;
 273                         break;
 274
 275                 case 'q':
 276                         conf.tls_redirect = 1;
 277                         break;
 278
 279                 case 's':
 280                         n_tls++;
 281                         /* fall through */
 282 #else
 283                 case 'C':
 284                 case 'K':
 285                 case 'q':
 286                 case 's':
 287                         fprintf(stderr, "uhttpd: TLS support not compiled, "
 288                                         "ignoring -%c\n", ch);
 289                         break;
 290 #endif
 291                 case 'p':
 292                         optarg = strdup(optarg);
 293                         bound += add_listener_arg(optarg, (ch == 's'));
 294                         break;
 295
 296                 case 'h':
 297                         if (!realpath(optarg, uh_buf)) {
 298                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 299                                                 optarg, strerror(errno));
 300                                 exit(1);
 301                         }
 302                         conf.docroot = strdup(uh_buf);
 303                         break;
 304
 305                 case 'H':
 306                         if (uh_handler_add(optarg)) {
 307                                 fprintf(stderr, "Error: Failed to load handler script %s\n",
 308                                         optarg);
 309                                 exit(1);
 310                         }
 311                         break;
 312
 313                 case 'E':
 314                         if (optarg[0] != '/') {
 315                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 316                                                 optarg);
 317                                 exit(1);
 318                         }
 319                         conf.error_handler = optarg;
 320                         break;
 321
 322                 case 'I':
 323                         if (optarg[0] == '/') {
 324                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 325                                                 optarg);
 326                                 exit(1);
 327                         }
 328                         uh_index_add(optarg);
 329                         break;
 330
 331                 case 'S':
 332                         conf.no_symlinks = 1;
 333                         break;
 334
 335                 case 'D':
 336                         conf.no_dirlists = 1;
 337                         break;
 338
 339                 case 'R':
 340                         conf.rfc1918_filter = 1;
 341                         break;
 342
 343                 case 'n':
 344                         conf.max_script_requests = atoi(optarg);
 345                         break;
 346
 347                 case 'N':
 348                         conf.max_connections = atoi(optarg);
 349                         break;
 350
 351                 case 'x':
 352                         fixup_prefix(optarg);
 353                         conf.cgi_prefix = optarg;
 354                         break;
 355
 356                 case 'y':
 357                         alias = calloc(1, sizeof(*alias));
 358                         if (!alias) {
 359                                 fprintf(stderr, "Error: failed to allocate alias\n");
 360                                 exit(1);
 361                         }
 362                         alias->alias = strdup(optarg);
 363                         alias->path = strchr(alias->alias, '=');
 364                         if (alias->path)
 365                                 *alias->path++ = 0;
 366                         list_add(&alias->list, &conf.cgi_alias);
 367                         break;
 368
 369                 case 'i':
 370                         optarg = strdup(optarg);
 371                         port = strchr(optarg, '=');
 372                         if (optarg[0] != '.' || !port) {
 373                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 374                                                 optarg);
 375                                 exit(1);
 376                         }
 377
 378                         *port++ = 0;
 379                         uh_interpreter_add(optarg, port);
 380                         break;
 381
 382                 case 't':
 383                         conf.script_timeout = atoi(optarg);
 384                         break;
 385
 386                 case 'T':
 387                         conf.network_timeout = atoi(optarg);
 388                         break;
 389
 390                 case 'k':
 391                         conf.http_keepalive = atoi(optarg);
 392                         break;
 393
 394                 case 'A':
 395                         conf.tcp_keepalive = atoi(optarg);
 396                         break;
 397
 398                 case 'f':
 399                         nofork = 1;
 400                         break;
 401
 402                 case 'd':
 403                         optarg = strdup(optarg);
 404                         port = alloca(strlen(optarg) + 1);
 405                         if (!port)
 406                                 return -1;
 407
 408                         /* "decode" plus to space to retain compat */
 409                         for (opt = 0; optarg[opt]; opt++)
 410                                 if (optarg[opt] == '+')
 411                                         optarg[opt] = ' ';
 412
 413                         /* opt now contains strlen(optarg) -- no need to re-scan */
 414                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 415                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 416                                 return -1;
 417                         }
 418
 419                         printf("%s", port);
 420                         return 0;
 421                         break;
 422
 423                 /* basic auth realm */
 424                 case 'r':
 425                         conf.realm = optarg;
 426                         break;
 427
 428                 /* md5 crypt */
 429                 case 'm':
 430                         printf("%s\n", crypt(optarg, "$1$"));
 431                         return 0;
 432                         break;
 433
 434                 /* config file */
 435                 case 'c':
 436                         conf.file = optarg;
 437                         break;
 438
 439 #ifdef HAVE_LUA
 440                 case 'l':
 441                 case 'L':
 442                         if (ch == 'l') {
 443                                 if (lua_prefix)
 444                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 445                                                 ch, lua_prefix);
 446
 447                                 lua_prefix = optarg;
 448                         }
 449                         else {
 450                                 if (lua_handler)
 451                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 452                                                 ch, lua_handler);
 453
 454                                 lua_handler = optarg;
 455                         }
 456
 457                         if (lua_prefix && lua_handler) {
 458                                 add_lua_prefix(lua_prefix, lua_handler);
 459                                 lua_prefix = NULL;
 460                                 lua_handler = NULL;
 461                         }
 462
 463                         break;
 464 #else
 465                 case 'l':
 466                 case 'L':
 467                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 468                                         "ignoring -%c\n", ch);
 469                         break;
 470 #endif
 471 #ifdef HAVE_UBUS
 472                 case 'a':
 473                         conf.ubus_noauth = 1;
 474                         break;
 475
 476                 case 'u':
 477                         conf.ubus_prefix = optarg;
 478                         break;
 479
 480                 case 'U':
 481                         conf.ubus_socket = optarg;
 482                         break;
 483
 484                 case 'X':
 485                         conf.ubus_cors = 1;
 486                         break;
 487 #else
 488                 case 'a':
 489                 case 'u':
 490                 case 'U':
 491                 case 'X':
 492                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 493                                         "ignoring -%c\n", ch);
 494                         break;
 495 #endif
 496                 default:
 497                         return usage(argv[0]);
 498                 }
 499         }
 500
 501         uh_config_parse();
 502
 503         if (!conf.docroot) {
 504                 if (!realpath(".", uh_buf)) {
 505                         fprintf(stderr, "Error: Unable to determine work dir\n");
 506                         return 1;
 507                 }
 508                 conf.docroot = strdup(uh_buf);
 509         }
 510
 511         init_defaults_post();
 512
 513         if (!bound) {
 514                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 515                 return 1;
 516         }
 517
 518 #ifdef HAVE_TLS
 519         if (n_tls) {
 520                 if (!tls_crt || !tls_key) {
 521                         fprintf(stderr, "Please specify a certificate and "
 522                                         "a key file to enable SSL support\n");
 523                         return 1;
 524                 }
 525
 526                 if (uh_tls_init(tls_key, tls_crt))
 527                     return 1;
 528         }
 529 #endif
 530
 531 #ifdef HAVE_LUA
 532         if (lua_handler || lua_prefix) {
 533                 fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 534                 return 1;
 535         }
 536
 537         if (!list_empty(&conf.lua_prefix) && uh_plugin_init("uhttpd_lua.so"))
 538                 return 1;
 539 #endif
 540 #ifdef HAVE_UBUS
 541         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 542                 return 1;
 543 #endif
 544
 545         /* fork (if not disabled) */
 546         if (!nofork) {
 547                 switch (fork()) {
 548                 case -1:
 549                         perror("fork()");
 550                         exit(1);
 551
 552                 case 0:
 553                         /* daemon setup */
 554                         if (chdir("/"))
 555                                 perror("chdir()");
 556
 557                         cur_fd = open("/dev/null", O_WRONLY);
 558                         if (cur_fd > 0) {
 559                                 dup2(cur_fd, 0);
 560                                 dup2(cur_fd, 1);
 561                                 dup2(cur_fd, 2);
 562                         }
 563
 564                         break;
 565
 566                 default:
 567                         exit(0);
 568                 }
 569         }
 570
 571         return run_server();
 572 }