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