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