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                         free(optarg);
 332                         break;
 333
 334                 case 'h':
 335                         if (!realpath(optarg, uh_buf)) {
 336                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 337                                                 optarg, strerror(errno));
 338                                 exit(1);
 339                         }
 340                         conf.docroot = strdup(uh_buf);
 341                         break;
 342
 343                 case 'H':
 344                         if (uh_handler_add(optarg)) {
 345                                 fprintf(stderr, "Error: Failed to load handler script %s\n",
 346                                         optarg);
 347                                 exit(1);
 348                         }
 349                         break;
 350
 351                 case 'E':
 352                         if (optarg[0] != '/') {
 353                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 354                                                 optarg);
 355                                 exit(1);
 356                         }
 357                         conf.error_handler = optarg;
 358                         break;
 359
 360                 case 'I':
 361                         if (optarg[0] == '/') {
 362                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 363                                                 optarg);
 364                                 exit(1);
 365                         }
 366                         uh_index_add(optarg);
 367                         break;
 368
 369                 case 'b':
 370                         conf.dirlist_charset = optarg;
 371                         break;
 372
 373                 case 'S':
 374                         conf.no_symlinks = 1;
 375                         break;
 376
 377                 case 'D':
 378                         conf.no_dirlists = 1;
 379                         break;
 380
 381                 case 'R':
 382                         conf.rfc1918_filter = 1;
 383                         break;
 384
 385                 case 'n':
 386                         conf.max_script_requests = atoi(optarg);
 387                         break;
 388
 389                 case 'N':
 390                         conf.max_connections = atoi(optarg);
 391                         break;
 392
 393                 case 'x':
 394                         fixup_prefix(optarg);
 395                         conf.cgi_prefix = optarg;
 396                         break;
 397
 398                 case 'y':
 399                         alias = calloc(1, sizeof(*alias));
 400                         if (!alias) {
 401                                 fprintf(stderr, "Error: failed to allocate alias\n");
 402                                 exit(1);
 403                         }
 404                         alias->alias = strdup(optarg);
 405                         alias->path = strchr(alias->alias, '=');
 406                         if (alias->path)
 407                                 *alias->path++ = 0;
 408                         list_add(&alias->list, &conf.cgi_alias);
 409                         break;
 410
 411                 case 'i':
 412                         optarg = strdup(optarg);
 413                         port = strchr(optarg, '=');
 414                         if (optarg[0] != '.' || !port) {
 415                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 416                                                 optarg);
 417                                 exit(1);
 418                         }
 419
 420                         *port++ = 0;
 421                         uh_interpreter_add(optarg, port);
 422                         break;
 423
 424                 case 't':
 425                         conf.script_timeout = atoi(optarg);
 426                         break;
 427
 428                 case 'T':
 429                         conf.network_timeout = atoi(optarg);
 430                         break;
 431
 432                 case 'k':
 433                         conf.http_keepalive = atoi(optarg);
 434                         break;
 435
 436                 case 'A':
 437                         conf.tcp_keepalive = atoi(optarg);
 438                         break;
 439
 440                 case 'f':
 441                         nofork = 1;
 442                         break;
 443
 444                 case 'd':
 445                         optarg = strdup(optarg);
 446                         port = alloca(strlen(optarg) + 1);
 447                         if (!port)
 448                                 return -1;
 449
 450                         /* "decode" plus to space to retain compat */
 451                         for (opt = 0; optarg[opt]; opt++)
 452                                 if (optarg[opt] == '+')
 453                                         optarg[opt] = ' ';
 454
 455                         /* opt now contains strlen(optarg) -- no need to re-scan */
 456                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 457                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 458                                 return -1;
 459                         }
 460
 461                         printf("%s", port);
 462                         return 0;
 463                         break;
 464
 465                 /* basic auth realm */
 466                 case 'r':
 467                         conf.realm = optarg;
 468                         break;
 469
 470                 /* md5 crypt */
 471                 case 'm':
 472                         printf("%s\n", crypt(optarg, "$1$"));
 473                         return 0;
 474                         break;
 475
 476                 /* config file */
 477                 case 'c':
 478                         conf.file = optarg;
 479                         break;
 480
 481 #ifdef HAVE_LUA
 482                 case 'l':
 483                 case 'L':
 484                         if (ch == 'l') {
 485                                 if (lua_prefix)
 486                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 487                                                 ch, lua_prefix);
 488
 489                                 lua_prefix = optarg;
 490                         }
 491                         else {
 492                                 if (lua_handler)
 493                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 494                                                 ch, lua_handler);
 495
 496                                 lua_handler = optarg;
 497                         }
 498
 499                         if (lua_prefix && lua_handler) {
 500                                 add_lua_prefix(lua_prefix, lua_handler);
 501                                 lua_prefix = NULL;
 502                                 lua_handler = NULL;
 503                         }
 504
 505                         break;
 506 #else
 507                 case 'l':
 508                 case 'L':
 509                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 510                                         "ignoring -%c\n", ch);
 511                         break;
 512 #endif
 513 #ifdef HAVE_UCODE
 514                 case 'o':
 515                 case 'O':
 516                         if (ch == 'o') {
 517                                 if (ucode_prefix)
 518                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 519                                                 ch, ucode_prefix);
 520
 521                                 ucode_prefix = optarg;
 522                         }
 523                         else {
 524                                 if (ucode_handler)
 525                                         fprintf(stderr, "uhttpd: Ignoring previous -%c %s\n",
 526                                                 ch, ucode_handler);
 527
 528                                 ucode_handler = optarg;
 529                         }
 530
 531                         if (ucode_prefix && ucode_handler) {
 532                                 add_ucode_prefix(ucode_prefix, ucode_handler);
 533                                 ucode_prefix = NULL;
 534                                 ucode_handler = NULL;
 535                         }
 536
 537                         break;
 538 #else
 539                 case 'o':
 540                 case 'O':
 541                         fprintf(stderr, "uhttpd: ucode support not compiled, "
 542                                         "ignoring -%c\n", ch);
 543                         break;
 544 #endif
 545 #ifdef HAVE_UBUS
 546                 case 'a':
 547                         conf.ubus_noauth = 1;
 548                         break;
 549
 550                 case 'u':
 551                         conf.ubus_prefix = optarg;
 552                         break;
 553
 554                 case 'U':
 555                         conf.ubus_socket = optarg;
 556                         break;
 557
 558                 case 'X':
 559                         conf.ubus_cors = 1;
 560                         break;
 561
 562                 case 'e':
 563                         conf.events_retry = atoi(optarg);
 564                         break;
 565 #else
 566                 case 'a':
 567                 case 'u':
 568                 case 'U':
 569                 case 'X':
 570                 case 'e':
 571                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 572                                         "ignoring -%c\n", ch);
 573                         break;
 574 #endif
 575                 default:
 576                         return usage(argv[0]);
 577                 }
 578         }
 579
 580         uh_config_parse();
 581
 582         if (!conf.docroot) {
 583                 if (!realpath(".", uh_buf)) {
 584                         fprintf(stderr, "Error: Unable to determine work dir\n");
 585                         return 1;
 586                 }
 587                 conf.docroot = strdup(uh_buf);
 588         }
 589
 590         init_defaults_post();
 591
 592         if (!bound) {
 593                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 594                 return 1;
 595         }
 596
 597 #ifdef HAVE_TLS
 598         if (n_tls) {
 599                 if (!tls_crt || !tls_key) {
 600                         fprintf(stderr, "Please specify a certificate and "
 601                                         "a key file to enable SSL support\n");
 602                         return 1;
 603                 }
 604
 605                 if (uh_tls_init(tls_key, tls_crt, tls_ciphers))
 606                     return 1;
 607         }
 608 #endif
 609
 610 #ifdef HAVE_LUA
 611         if (lua_handler || lua_prefix) {
 612                 fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 613                 return 1;
 614         }
 615
 616         if (!list_empty(&conf.lua_prefix) && uh_plugin_init("uhttpd_lua.so"))
 617                 return 1;
 618 #endif
 619 #ifdef HAVE_UCODE
 620         if (ucode_handler || ucode_prefix) {
 621                 fprintf(stderr, "Need handler and prefix to enable ucode support\n");
 622                 return 1;
 623         }
 624
 625         if (!list_empty(&conf.ucode_prefix) && uh_plugin_init("uhttpd_ucode.so"))
 626                 return 1;
 627 #endif
 628 #ifdef HAVE_UBUS
 629         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 630                 return 1;
 631 #endif
 632
 633         /* fork (if not disabled) */
 634         if (!nofork) {
 635                 switch (fork()) {
 636                 case -1:
 637                         perror("fork()");
 638                         exit(1);
 639
 640                 case 0:
 641                         /* daemon setup */
 642                         if (chdir("/"))
 643                                 perror("chdir()");
 644
 645                         cur_fd = open("/dev/null", O_WRONLY);
 646                         if (cur_fd > 0) {
 647                                 dup2(cur_fd, 0);
 648                                 dup2(cur_fd, 1);
 649                                 dup2(cur_fd, 2);
 650                         }
 651
 652                         break;
 653
 654                 default:
 655                         exit(0);
 656                 }
 657         }
 658
 659         return run_server();
 660 }