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 #define _BSD_SOURCE
  21 #define _GNU_SOURCE
  22 #define _XOPEN_SOURCE   700
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26
  27 #include <getopt.h>
  28 #include <errno.h>
  29 #include <netdb.h>
  30 #include <signal.h>
  31
  32 #include <libubox/usock.h>
  33
  34 #include "uhttpd.h"
  35 #include "tls.h"
  36
  37 char uh_buf[4096];
  38
  39 static int run_server(void)
  40 {
  41         uloop_init();
  42         uh_setup_listeners();
  43         uh_plugin_post_init();
  44         uloop_run();
  45
  46         return 0;
  47 }
  48
  49 static void uh_config_parse(void)
  50 {
  51         const char *path = conf.file;
  52         FILE *c;
  53         char line[512];
  54         char *col1;
  55         char *col2;
  56         char *eol;
  57
  58         if (!path)
  59                 path = "/etc/httpd.conf";
  60
  61         c = fopen(path, "r");
  62         if (!c)
  63                 return;
  64
  65         memset(line, 0, sizeof(line));
  66
  67         while (fgets(line, sizeof(line) - 1, c)) {
  68                 if ((line[0] == '/') && (strchr(line, ':') != NULL)) {
  69                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  70                                 !(col2 = strchr(col1, ':')) || (*col2++ = 0) ||
  71                                 !(eol = strchr(col2, '\n')) || (*eol++  = 0))
  72                                 continue;
  73
  74                         uh_auth_add(line, col1, col2);
  75                 } else if (!strncmp(line, "I:", 2)) {
  76                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  77                                 !(eol = strchr(col1, '\n')) || (*eol++  = 0))
  78                                 continue;
  79
  80                         uh_index_add(strdup(col1));
  81                 } else if (!strncmp(line, "E404:", 5)) {
  82                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  83                                 !(eol = strchr(col1, '\n')) || (*eol++  = 0))
  84                                 continue;
  85
  86                         conf.error_handler = strdup(col1);
  87                 }
  88                 else if ((line[0] == '*') && (strchr(line, ':') != NULL)) {
  89                         if (!(col1 = strchr(line, '*')) || (*col1++ = 0) ||
  90                                 !(col2 = strchr(col1, ':')) || (*col2++ = 0) ||
  91                                 !(eol = strchr(col2, '\n')) || (*eol++  = 0))
  92                                 continue;
  93
  94                         uh_interpreter_add(col1, col2);
  95                 }
  96         }
  97
  98         fclose(c);
  99 }
 100
 101 static int add_listener_arg(char *arg, bool tls)
 102 {
 103         char *host = NULL;
 104         char *port = arg;
 105         char *s;
 106         int l;
 107
 108         s = strrchr(arg, ':');
 109         if (s) {
 110                 host = arg;
 111                 port = s + 1;
 112                 *s = 0;
 113         }
 114
 115         if (host && *host == '[') {
 116                 l = strlen(host);
 117                 if (l >= 2) {
 118                         host[l-1] = 0;
 119                         host++;
 120                 }
 121         }
 122
 123         return uh_socket_bind(host, port, tls);
 124 }
 125
 126 static int usage(const char *name)
 127 {
 128         fprintf(stderr,
 129                 "Usage: %s -p [addr:]port -h docroot\n"
 130                 "       -f              Do not fork to background\n"
 131                 "       -c file         Configuration file, default is '/etc/httpd.conf'\n"
 132                 "       -p [addr:]port  Bind to specified address and port, multiple allowed\n"
 133 #ifdef HAVE_TLS
 134                 "       -s [addr:]port  Like -p but provide HTTPS on this port\n"
 135                 "       -C file         ASN.1 server certificate file\n"
 136                 "       -K file         ASN.1 server private key file\n"
 137 #endif
 138                 "       -h directory    Specify the document root, default is '.'\n"
 139                 "       -E string       Use given virtual URL as 404 error handler\n"
 140                 "       -I string       Use given filename as index for directories, multiple allowed\n"
 141                 "       -S              Do not follow symbolic links outside of the docroot\n"
 142                 "       -D              Do not allow directory listings, send 403 instead\n"
 143                 "       -R              Enable RFC1918 filter\n"
 144                 "       -n count        Maximum allowed number of concurrent script requests\n"
 145                 "       -N count        Maximum allowed number of concurrent connections\n"
 146 #ifdef HAVE_LUA
 147                 "       -l string       URL prefix for Lua handler, default is '/lua'\n"
 148                 "       -L file         Lua handler script, omit to disable Lua\n"
 149 #endif
 150 #ifdef HAVE_UBUS
 151                 "       -u string       URL prefix for UBUS via JSON-RPC handler\n"
 152                 "       -U file         Override ubus socket path\n"
 153                 "       -a              Do not authenticate JSON-RPC requests against UBUS session api\n"
 154 #endif
 155                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 156                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 157                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 158                 "       -T seconds      Network timeout in seconds, default is 30\n"
 159                 "       -k seconds      HTTP keepalive timeout\n"
 160                 "       -d string       URL decode given string\n"
 161                 "       -r string       Specify basic auth realm\n"
 162                 "       -m string       MD5 crypt given string\n"
 163                 "\n", name
 164         );
 165         return 1;
 166 }
 167
 168 static void init_defaults_pre(void)
 169 {
 170         conf.script_timeout = 60;
 171         conf.network_timeout = 30;
 172         conf.http_keepalive = 20;
 173         conf.max_script_requests = 3;
 174         conf.max_connections = 100;
 175         conf.realm = "Protected Area";
 176         conf.cgi_prefix = "/cgi-bin";
 177         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 178 }
 179
 180 static void init_defaults_post(void)
 181 {
 182         uh_index_add("index.html");
 183         uh_index_add("index.htm");
 184         uh_index_add("default.html");
 185         uh_index_add("default.htm");
 186
 187         if (conf.cgi_prefix) {
 188                 char *str = malloc(strlen(conf.docroot) + strlen(conf.cgi_prefix) + 1);
 189                 strcpy(str, conf.docroot);
 190                 strcat(str, conf.cgi_prefix);
 191                 conf.cgi_docroot_path = str;
 192         };
 193 }
 194
 195 static void fixup_prefix(char *str)
 196 {
 197         int len;
 198
 199         if (!str || !str[0])
 200                 return;
 201
 202         len = strlen(str) - 1;
 203
 204         while (len >= 0 && str[len] == '/')
 205                 len--;
 206
 207         str[len + 1] = 0;
 208 }
 209
 210 int main(int argc, char **argv)
 211 {
 212         bool nofork = false;
 213         char *port;
 214         int opt, ch;
 215         int cur_fd;
 216         int bound = 0;
 217
 218 #ifdef HAVE_TLS
 219         int n_tls = 0;
 220         const char *tls_key = NULL, *tls_crt = NULL;
 221 #endif
 222
 223         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 224
 225         uh_dispatch_add(&cgi_dispatch);
 226         init_defaults_pre();
 227         signal(SIGPIPE, SIG_IGN);
 228
 229         while ((ch = getopt(argc, argv, "afSDRC:K:E:I:p:s:h:c:l:L:d:r:m:n:N:x:i:t:k:T:A:u:U:")) != -1) {
 230                 switch(ch) {
 231 #ifdef HAVE_TLS
 232                 case 'C':
 233                         tls_crt = optarg;
 234                         break;
 235
 236                 case 'K':
 237                         tls_key = optarg;
 238                         break;
 239
 240                 case 's':
 241                         n_tls++;
 242                         /* fall through */
 243 #else
 244                 case 'C':
 245                 case 'K':
 246                 case 's':
 247                         fprintf(stderr, "uhttpd: TLS support not compiled, "
 248                                         "ignoring -%c\n", opt);
 249                         break;
 250 #endif
 251                 case 'p':
 252                         optarg = strdup(optarg);
 253                         bound += add_listener_arg(optarg, (ch == 's'));
 254                         break;
 255
 256                 case 'h':
 257                         if (!realpath(optarg, uh_buf)) {
 258                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 259                                                 optarg, strerror(errno));
 260                                 exit(1);
 261                         }
 262                         conf.docroot = strdup(uh_buf);
 263                         break;
 264
 265                 case 'E':
 266                         if (optarg[0] != '/') {
 267                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 268                                                 optarg);
 269                                 exit(1);
 270                         }
 271                         conf.error_handler = optarg;
 272                         break;
 273
 274                 case 'I':
 275                         if (optarg[0] == '/') {
 276                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 277                                                 optarg);
 278                                 exit(1);
 279                         }
 280                         uh_index_add(optarg);
 281                         break;
 282
 283                 case 'S':
 284                         conf.no_symlinks = 1;
 285                         break;
 286
 287                 case 'D':
 288                         conf.no_dirlists = 1;
 289                         break;
 290
 291                 case 'R':
 292                         conf.rfc1918_filter = 1;
 293                         break;
 294
 295                 case 'n':
 296                         conf.max_script_requests = atoi(optarg);
 297                         break;
 298
 299                 case 'N':
 300                         conf.max_connections = atoi(optarg);
 301                         break;
 302
 303                 case 'x':
 304                         fixup_prefix(optarg);
 305                         conf.cgi_prefix = optarg;
 306                         break;
 307
 308                 case 'i':
 309                         optarg = strdup(optarg);
 310                         port = strchr(optarg, '=');
 311                         if (optarg[0] != '.' || !port) {
 312                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 313                                                 optarg);
 314                                 exit(1);
 315                         }
 316
 317                         *port++ = 0;
 318                         uh_interpreter_add(optarg, port);
 319                         break;
 320
 321                 case 't':
 322                         conf.script_timeout = atoi(optarg);
 323                         break;
 324
 325                 case 'T':
 326                         conf.network_timeout = atoi(optarg);
 327                         break;
 328
 329                 case 'k':
 330                         conf.http_keepalive = atoi(optarg);
 331                         break;
 332
 333                 case 'A':
 334                         conf.tcp_keepalive = atoi(optarg);
 335                         break;
 336
 337                 case 'f':
 338                         nofork = 1;
 339                         break;
 340
 341                 case 'd':
 342                         optarg = strdup(optarg);
 343                         port = alloca(strlen(optarg) + 1);
 344                         if (!port)
 345                                 return -1;
 346
 347                         /* "decode" plus to space to retain compat */
 348                         for (opt = 0; optarg[opt]; opt++)
 349                                 if (optarg[opt] == '+')
 350                                         optarg[opt] = ' ';
 351
 352                         /* opt now contains strlen(optarg) -- no need to re-scan */
 353                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 354                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 355                                 return -1;
 356                         }
 357
 358                         printf("%s", port);
 359                         return 0;
 360                         break;
 361
 362                 /* basic auth realm */
 363                 case 'r':
 364                         conf.realm = optarg;
 365                         break;
 366
 367                 /* md5 crypt */
 368                 case 'm':
 369                         printf("%s\n", crypt(optarg, "$1$"));
 370                         return 0;
 371                         break;
 372
 373                 /* config file */
 374                 case 'c':
 375                         conf.file = optarg;
 376                         break;
 377
 378 #ifdef HAVE_LUA
 379                 case 'l':
 380                         conf.lua_prefix = optarg;
 381                         break;
 382
 383                 case 'L':
 384                         conf.lua_handler = optarg;
 385                         break;
 386 #else
 387                 case 'l':
 388                 case 'L':
 389                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 390                                         "ignoring -%c\n", opt);
 391                         break;
 392 #endif
 393 #ifdef HAVE_UBUS
 394                 case 'a':
 395                         conf.ubus_noauth = 1;
 396                         break;
 397
 398                 case 'u':
 399                         conf.ubus_prefix = optarg;
 400                         break;
 401
 402                 case 'U':
 403                         conf.ubus_socket = optarg;
 404                         break;
 405 #else
 406                 case 'a':
 407                 case 'u':
 408                 case 'U':
 409                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 410                                         "ignoring -%c\n", opt);
 411                         break;
 412 #endif
 413                 default:
 414                         return usage(argv[0]);
 415                 }
 416         }
 417
 418         uh_config_parse();
 419
 420         if (!conf.docroot) {
 421                 if (!realpath(".", uh_buf)) {
 422                         fprintf(stderr, "Error: Unable to determine work dir\n");
 423                         return 1;
 424                 }
 425                 conf.docroot = strdup(uh_buf);
 426         }
 427
 428         init_defaults_post();
 429
 430         if (!bound) {
 431                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 432                 return 1;
 433         }
 434
 435 #ifdef HAVE_TLS
 436         if (n_tls) {
 437                 if (!tls_crt || !tls_key) {
 438                         fprintf(stderr, "Please specify a certificate and "
 439                                         "a key file to enable SSL support\n");
 440                         return 1;
 441                 }
 442
 443                 if (uh_tls_init(tls_key, tls_crt))
 444                     return 1;
 445         }
 446 #endif
 447
 448 #ifdef HAVE_LUA
 449         if (conf.lua_handler || conf.lua_prefix) {
 450                 if (!conf.lua_handler || !conf.lua_prefix) {
 451                         fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 452                         return 1;
 453                 }
 454                 if (uh_plugin_init("uhttpd_lua.so"))
 455                         return 1;
 456         }
 457 #endif
 458 #ifdef HAVE_UBUS
 459         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 460                 return 1;
 461 #endif
 462
 463         /* fork (if not disabled) */
 464         if (!nofork) {
 465                 switch (fork()) {
 466                 case -1:
 467                         perror("fork()");
 468                         exit(1);
 469
 470                 case 0:
 471                         /* daemon setup */
 472                         if (chdir("/"))
 473                                 perror("chdir()");
 474
 475                         cur_fd = open("/dev/null", O_WRONLY);
 476                         if (cur_fd > 0) {
 477                                 dup2(cur_fd, 0);
 478                                 dup2(cur_fd, 1);
 479                                 dup2(cur_fd, 2);
 480                         }
 481
 482                         break;
 483
 484                 default:
 485                         exit(0);
 486                 }
 487         }
 488
 489         return run_server();
 490 }