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                 "       -b string       Use given charset for directory listings, default to UTF-8\n"
 148                 "       -I string       Use given filename as index for directories, multiple allowed\n"
 149                 "       -S              Do not follow symbolic links outside of the docroot\n"
 150                 "       -D              Do not allow directory listings, send 403 instead\n"
 151                 "       -R              Enable RFC1918 filter\n"
 152                 "       -n count        Maximum allowed number of concurrent script requests\n"
 153                 "       -N count        Maximum allowed number of concurrent connections\n"
 154 #ifdef HAVE_LUA
 155                 "       -l string       URL prefix for Lua handler\n"
 156                 "       -L file         Path to Lua handler script, -l and -L may be repeated in pairs\n"
 157 #endif
 158 #ifdef HAVE_UCODE
 159                 "       -o string       URL prefix for ucode handler\n"
 160                 "       -O file         Path to ucode handler script, -o and -O may be repeated in pairs\n"
 161 #endif
 162 #ifdef HAVE_UBUS
 163                 "       -u string       URL prefix for UBUS via JSON-RPC handler\n"
 164                 "       -U file         Override ubus socket path\n"
 165                 "       -a              Do not authenticate JSON-RPC requests against UBUS session api\n"
 166                 "       -X              Enable CORS HTTP headers on JSON-RPC api\n"
 167                 "       -e              Events subscription reconnection time (retry value)\n"
 168 #endif
 169                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 170                 "       -y alias[=path] URL alias handle\n"
 171                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 172                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 173                 "       -T seconds      Network timeout in seconds, default is 30\n"
 174                 "       -k seconds      HTTP keepalive timeout\n"
 175                 "       -A seconds      TCP keepalive timeout, default is unset\n"
 176                 "       -d string       URL decode given string\n"
 177                 "       -r string       Specify basic auth realm\n"
 178                 "       -m string       MD5 crypt given string\n"
 179                 "\n", name
 180         );
 181         return 1;
 182 }
 183
 184 static void init_defaults_pre(void)
 185 {
 186         conf.script_timeout = 60;
 187         conf.network_timeout = 30;
 188         conf.http_keepalive = 20;
 189         conf.max_script_requests = 3;
 190         conf.max_connections = 100;
 191         conf.realm = "Protected Area";
 192         conf.cgi_prefix = "/cgi-bin";
 193         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 194         INIT_LIST_HEAD(&conf.cgi_alias);
 195         INIT_LIST_HEAD(&conf.lua_prefix);
 196 #if HAVE_UCODE
 197         INIT_LIST_HEAD(&conf.ucode_prefix);
 198 #endif
 199 }
 200
 201 static void init_defaults_post(void)
 202 {
 203         uh_index_add("index.html");
 204         uh_index_add("index.htm");
 205         uh_index_add("default.html");
 206         uh_index_add("default.htm");
 207
 208         if (conf.cgi_prefix) {
 209                 char *str = malloc(strlen(conf.docroot) + strlen(conf.cgi_prefix) + 1);
 210
 211                 strcpy(str, conf.docroot);
 212                 strcat(str, conf.cgi_prefix);
 213                 conf.cgi_docroot_path = str;
 214                 conf.cgi_prefix_len = strlen(conf.cgi_prefix);
 215         };
 216 }
 217
 218 static void fixup_prefix(char *str)
 219 {
 220         int len;
 221
 222         if (!str || !str[0])
 223                 return;
 224
 225         len = strlen(str) - 1;
 226
 227         while (len >= 0 && str[len] == '/')
 228                 len--;
 229
 230         str[len + 1] = 0;
 231 }
 232
 233 #ifdef HAVE_LUA
 234 static void add_lua_prefix(const char *prefix, const char *handler) {
 235         struct lua_prefix *p;
 236         char *pprefix, *phandler;
 237
 238         p = calloc_a(sizeof(*p),
 239                      &pprefix, strlen(prefix) + 1,
 240                      &phandler, strlen(handler) + 1);
 241
 242         if (!p)
 243                 return;
 244
 245         p->prefix = strcpy(pprefix, prefix);
 246         p->handler = strcpy(phandler, handler);
 247
 248         list_add_tail(&p->list, &conf.lua_prefix);
 249 }
 250 #endif
 251
 252 #ifdef HAVE_UCODE
 253 static void add_ucode_prefix(const char *prefix, const char *handler) {
 254         struct ucode_prefix *p;
 255         char *pprefix, *phandler;
 256
 257         p = calloc_a(sizeof(*p),
 258                      &pprefix, strlen(prefix) + 1,
 259                      &phandler, strlen(handler) + 1);
 260
 261         if (!p)
 262                 return;
 263
 264         p->prefix = strcpy(pprefix, prefix);
 265         p->handler = strcpy(phandler, handler);
 266
 267         list_add_tail(&p->list, &conf.ucode_prefix);
 268 }
 269 #endif
 270
 271 int main(int argc, char **argv)
 272 {
 273         struct alias *alias;
 274         bool nofork = false;
 275         char *port;
 276         int opt, ch;
 277         int cur_fd;
 278         int bound = 0;
 279 #ifdef HAVE_TLS
 280         int n_tls = 0;
 281         const char *tls_key = NULL, *tls_crt = NULL, *tls_ciphers = NULL;
 282 #endif
 283 #ifdef HAVE_LUA
 284         const char *lua_prefix = NULL, *lua_handler = NULL;
 285 #endif
 286 #ifdef HAVE_UCODE
 287         const char *ucode_prefix = NULL, *ucode_handler = NULL;
 288 #endif
 289
 290         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 291
 292         uh_dispatch_add(&cgi_dispatch);
 293         init_defaults_pre();
 294         signal(SIGPIPE, SIG_IGN);
 295
 296         while ((ch = getopt(argc, argv, "A:ab:C:c:Dd:E:e:fh:H:I:i:K:k:L:l:m:N:n:O:o:P:p:qRr:Ss:T:t:U:u:Xx:y:")) != -1) {
 297                 switch(ch) {
 298 #ifdef HAVE_TLS
 299                 case 'C':
 300                         tls_crt = optarg;
 301                         break;
 302
 303                 case 'K':
 304                         tls_key = optarg;
 305                         break;
 306
 307                 case 'P':
 308                         tls_ciphers = optarg;
 309                         break;
 310
 311                 case 'q':
 312                         conf.tls_redirect = 1;
 313                         break;
 314
 315                 case 's':
 316                         n_tls++;
 317                         /* fall through */
 318 #else
 319                 case 'C':
 320                 case 'K':
 321                 case 'P':
 322                 case 'q':
 323                 case 's':
 324                         fprintf(stderr, "uhttpd: TLS support not compiled, "
 325                                         "ignoring -%c\n", ch);
 326                         break;
 327 #endif
 328                 case 'p':
 329                         optarg = strdup(optarg);
 330                         bound += add_listener_arg(optarg, (ch == 's'));
 331                         break;
 332
 333                 case 'h':
 334                         if (!realpath(optarg, uh_buf)) {
 335                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 336                                                 optarg, strerror(errno));
 337                                 exit(1);
 338                         }
 339                         conf.docroot = strdup(uh_buf);
 340                         break;
 341
 342                 case 'H':
 343                         if (uh_handler_add(optarg)) {
 344                                 fprintf(stderr, "Error: Failed to load handler script %s\n",
 345                                         optarg);
 346                                 exit(1);
 347                         }
 348                         break;
 349
 350                 case 'E':
 351                         if (optarg[0] != '/') {
 352                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 353                                                 optarg);
 354                                 exit(1);
 355                         }
 356                         conf.error_handler = optarg;
 357                         break;
 358
 359                 case 'I':
 360                         if (optarg[0] == '/') {
 361                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 362                                                 optarg);
 363                                 exit(1);
 364                         }
 365                         uh_index_add(optarg);
 366                         break;
 367
 368                 case 'b':
 369                         conf.dirlist_charset = optarg;
 370                         break;
 371
 372                 case 'S':
 373                         conf.no_symlinks = 1;
 374                         break;
 375
 376                 case 'D':
 377                         conf.no_dirlists = 1;
 378                         break;
 379
 380                 case 'R':
 381                         conf.rfc1918_filter = 1;
 382                         break;
 383
 384                 case 'n':
 385                         conf.max_script_requests = atoi(optarg);
 386                         break;
 387
 388                 case 'N':
 389                         conf.max_connections = atoi(optarg);
 390                         break;
 391
 392                 case 'x':
 393                         fixup_prefix(optarg);
 394                         conf.cgi_prefix = optarg;
 395                         break;
 396
 397                 case 'y':
 398                         alias = calloc(1, sizeof(*alias));
 399                         if (!alias) {
 400                                 fprintf(stderr, "Error: failed to allocate alias\n");
 401                                 exit(1);
 402                         }
 403                         alias->alias = strdup(optarg);
 404                         alias->path = strchr(alias->alias, '=');
 405                         if (alias->path)
 406                                 *alias->path++ = 0;
 407                         list_add(&alias->list, &conf.cgi_alias);
 408                         break;
 409
 410                 case 'i':
 411                         optarg = strdup(optarg);
 412                         port = strchr(optarg, '=');
 413                         if (optarg[0] != '.' || !port) {
 414                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 415                                                 optarg);
 416                                 exit(1);
 417                         }
 418
 419                         *port++ = 0;
 420                         uh_interpreter_add(optarg, port);
 421                         break;
 422
 423                 case 't':
 424                         conf.script_timeout = atoi(optarg);
 425                         break;
 426
 427                 case 'T':
 428                         conf.network_timeout = atoi(optarg);
 429                         break;
 430
 431                 case 'k':
 432                         conf.http_keepalive = atoi(optarg);
 433                         break;
 434
 435                 case 'A':
 436                         conf.tcp_keepalive = atoi(optarg);
 437                         break;
 438
 439                 case 'f':
 440                         nofork = 1;
 441                         break;
 442
 443                 case 'd':
 444                         optarg = strdup(optarg);
 445                         port = alloca(strlen(optarg) + 1);
 446                         if (!port)
 447                                 return -1;
 448
 449                         /* "decode" plus to space to retain compat */
 450                         for (opt = 0; optarg[opt]; opt++)
 451                                 if (optarg[opt] == '+')
 452                                         optarg[opt] = ' ';
 453
 454                         /* opt now contains strlen(optarg) -- no need to re-scan */
 455                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 456                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 457                                 return -1;
 458                         }
 459
 460                         printf("%s", port);
 461                         return 0;
 462                         break;
 463
 464                 /* basic auth realm */
 465                 case 'r':
 466                         conf.realm = optarg;
 467                         break;
 468
 469                 /* md5 crypt */
 470                 case 'm':
 471                         printf("%s\n", crypt(optarg, "$1$"));
 472                         return 0;
 473                         break;
 474
 475                 /* config file */
 476                 case 'c':
 477                         conf.file = optarg;
 478                         break;
 479
 480 #ifdef HAVE_LUA
 481                 case 'l':
 482                 case 'L':
 483                         if (ch == 'l') {
 484                                 if (lua_prefix)
 485                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 486                                                 ch, lua_prefix);
 487
 488                                 lua_prefix = optarg;
 489                         }
 490                         else {
 491                                 if (lua_handler)
 492                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 493                                                 ch, lua_handler);
 494
 495                                 lua_handler = optarg;
 496                         }
 497
 498                         if (lua_prefix && lua_handler) {
 499                                 add_lua_prefix(lua_prefix, lua_handler);
 500                                 lua_prefix = NULL;
 501                                 lua_handler = NULL;
 502                         }
 503
 504                         break;
 505 #else
 506                 case 'l':
 507                 case 'L':
 508                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 509                                         "ignoring -%c\n", ch);
 510                         break;
 511 #endif
 512 #ifdef HAVE_UCODE
 513                 case 'o':
 514                 case 'O':
 515                         if (ch == 'o') {
 516                                 if (ucode_prefix)
 517                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 518                                                 ch, ucode_prefix);
 519
 520                                 ucode_prefix = optarg;
 521                         }
 522                         else {
 523                                 if (ucode_handler)
 524                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 525                                                 ch, ucode_handler);
 526
 527                                 ucode_handler = optarg;
 528                         }
 529
 530                         if (ucode_prefix && ucode_handler) {
 531                                 add_ucode_prefix(ucode_prefix, ucode_handler);
 532                                 ucode_prefix = NULL;
 533                                 ucode_handler = NULL;
 534                         }
 535
 536                         break;
 537 #else
 538                 case 'o':
 539                 case 'O':
 540                         fprintf(stderr, "uhttpd: ucode support not compiled, "
 541                                         "ignoring -%c\n", ch);
 542                         break;
 543 #endif
 544 #ifdef HAVE_UBUS
 545                 case 'a':
 546                         conf.ubus_noauth = 1;
 547                         break;
 548
 549                 case 'u':
 550                         conf.ubus_prefix = optarg;
 551                         break;
 552
 553                 case 'U':
 554                         conf.ubus_socket = optarg;
 555                         break;
 556
 557                 case 'X':
 558                         conf.ubus_cors = 1;
 559                         break;
 560
 561                 case 'e':
 562                         conf.events_retry = atoi(optarg);
 563                         break;
 564 #else
 565                 case 'a':
 566                 case 'u':
 567                 case 'U':
 568                 case 'X':
 569                 case 'e':
 570                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 571                                         "ignoring -%c\n", ch);
 572                         break;
 573 #endif
 574                 default:
 575                         return usage(argv[0]);
 576                 }
 577         }
 578
 579         uh_config_parse();
 580
 581         if (!conf.docroot) {
 582                 if (!realpath(".", uh_buf)) {
 583                         fprintf(stderr, "Error: Unable to determine work dir\n");
 584                         return 1;
 585                 }
 586                 conf.docroot = strdup(uh_buf);
 587         }
 588
 589         init_defaults_post();
 590
 591         if (!bound) {
 592                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 593                 return 1;
 594         }
 595
 596 #ifdef HAVE_TLS
 597         if (n_tls) {
 598                 if (!tls_crt || !tls_key) {
 599                         fprintf(stderr, "Please specify a certificate and "
 600                                         "a key file to enable SSL support\n");
 601                         return 1;
 602                 }
 603
 604                 if (uh_tls_init(tls_key, tls_crt, tls_ciphers))
 605                     return 1;
 606         }
 607 #endif
 608
 609 #ifdef HAVE_LUA
 610         if (lua_handler || lua_prefix) {
 611                 fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 612                 return 1;
 613         }
 614
 615         if (!list_empty(&conf.lua_prefix) && uh_plugin_init("uhttpd_lua.so"))
 616                 return 1;
 617 #endif
 618 #ifdef HAVE_UCODE
 619         if (ucode_handler || ucode_prefix) {
 620                 fprintf(stderr, "Need handler and prefix to enable ucode support\n");
 621                 return 1;
 622         }
 623
 624         if (!list_empty(&conf.ucode_prefix) && uh_plugin_init("uhttpd_ucode.so"))
 625                 return 1;
 626 #endif
 627 #ifdef HAVE_UBUS
 628         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 629                 return 1;
 630 #endif
 631
 632         /* fork (if not disabled) */
 633         if (!nofork) {
 634                 switch (fork()) {
 635                 case -1:
 636                         perror("fork()");
 637                         exit(1);
 638
 639                 case 0:
 640                         /* daemon setup */
 641                         if (chdir("/"))
 642                                 perror("chdir()");
 643
 644                         cur_fd = open("/dev/null", O_WRONLY);
 645                         if (cur_fd > 0) {
 646                                 dup2(cur_fd, 0);
 647                                 dup2(cur_fd, 1);
 648                                 dup2(cur_fd, 2);
 649                         }
 650
 651                         break;
 652
 653                 default:
 654                         exit(0);
 655                 }
 656         }
 657
 658         return run_server();
 659 }