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                 "       -X              Enable CORS HTTP headers on JSON-RPC api\n"
 155 #endif
 156                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 157                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 158                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 159                 "       -T seconds      Network timeout in seconds, default is 30\n"
 160                 "       -k seconds      HTTP keepalive timeout\n"
 161                 "       -d string       URL decode given string\n"
 162                 "       -r string       Specify basic auth realm\n"
 163                 "       -m string       MD5 crypt given string\n"
 164                 "\n", name
 165         );
 166         return 1;
 167 }
 168
 169 static void init_defaults_pre(void)
 170 {
 171         conf.script_timeout = 60;
 172         conf.network_timeout = 30;
 173         conf.http_keepalive = 20;
 174         conf.max_script_requests = 3;
 175         conf.max_connections = 100;
 176         conf.realm = "Protected Area";
 177         conf.cgi_prefix = "/cgi-bin";
 178         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 179 }
 180
 181 static void init_defaults_post(void)
 182 {
 183         uh_index_add("index.html");
 184         uh_index_add("index.htm");
 185         uh_index_add("default.html");
 186         uh_index_add("default.htm");
 187
 188         if (conf.cgi_prefix) {
 189                 char *str = malloc(strlen(conf.docroot) + strlen(conf.cgi_prefix) + 1);
 190                 strcpy(str, conf.docroot);
 191                 strcat(str, conf.cgi_prefix);
 192                 conf.cgi_docroot_path = str;
 193         };
 194 }
 195
 196 static void fixup_prefix(char *str)
 197 {
 198         int len;
 199
 200         if (!str || !str[0])
 201                 return;
 202
 203         len = strlen(str) - 1;
 204
 205         while (len >= 0 && str[len] == '/')
 206                 len--;
 207
 208         str[len + 1] = 0;
 209 }
 210
 211 int main(int argc, char **argv)
 212 {
 213         bool nofork = false;
 214         char *port;
 215         int opt, ch;
 216         int cur_fd;
 217         int bound = 0;
 218
 219 #ifdef HAVE_TLS
 220         int n_tls = 0;
 221         const char *tls_key = NULL, *tls_crt = NULL;
 222 #endif
 223
 224         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 225
 226         uh_dispatch_add(&cgi_dispatch);
 227         init_defaults_pre();
 228         signal(SIGPIPE, SIG_IGN);
 229
 230         while ((ch = getopt(argc, argv, "afSDRXC:K:E:I:p:s:h:c:l:L:d:r:m:n:N:x:i:t:k:T:A:u:U:")) != -1) {
 231                 switch(ch) {
 232 #ifdef HAVE_TLS
 233                 case 'C':
 234                         tls_crt = optarg;
 235                         break;
 236
 237                 case 'K':
 238                         tls_key = optarg;
 239                         break;
 240
 241                 case 's':
 242                         n_tls++;
 243                         /* fall through */
 244 #else
 245                 case 'C':
 246                 case 'K':
 247                 case 's':
 248                         fprintf(stderr, "uhttpd: TLS support not compiled, "
 249                                         "ignoring -%c\n", opt);
 250                         break;
 251 #endif
 252                 case 'p':
 253                         optarg = strdup(optarg);
 254                         bound += add_listener_arg(optarg, (ch == 's'));
 255                         break;
 256
 257                 case 'h':
 258                         if (!realpath(optarg, uh_buf)) {
 259                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 260                                                 optarg, strerror(errno));
 261                                 exit(1);
 262                         }
 263                         conf.docroot = strdup(uh_buf);
 264                         break;
 265
 266                 case 'E':
 267                         if (optarg[0] != '/') {
 268                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 269                                                 optarg);
 270                                 exit(1);
 271                         }
 272                         conf.error_handler = optarg;
 273                         break;
 274
 275                 case 'I':
 276                         if (optarg[0] == '/') {
 277                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 278                                                 optarg);
 279                                 exit(1);
 280                         }
 281                         uh_index_add(optarg);
 282                         break;
 283
 284                 case 'S':
 285                         conf.no_symlinks = 1;
 286                         break;
 287
 288                 case 'D':
 289                         conf.no_dirlists = 1;
 290                         break;
 291
 292                 case 'R':
 293                         conf.rfc1918_filter = 1;
 294                         break;
 295
 296                 case 'n':
 297                         conf.max_script_requests = atoi(optarg);
 298                         break;
 299
 300                 case 'N':
 301                         conf.max_connections = atoi(optarg);
 302                         break;
 303
 304                 case 'x':
 305                         fixup_prefix(optarg);
 306                         conf.cgi_prefix = optarg;
 307                         break;
 308
 309                 case 'i':
 310                         optarg = strdup(optarg);
 311                         port = strchr(optarg, '=');
 312                         if (optarg[0] != '.' || !port) {
 313                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 314                                                 optarg);
 315                                 exit(1);
 316                         }
 317
 318                         *port++ = 0;
 319                         uh_interpreter_add(optarg, port);
 320                         break;
 321
 322                 case 't':
 323                         conf.script_timeout = atoi(optarg);
 324                         break;
 325
 326                 case 'T':
 327                         conf.network_timeout = atoi(optarg);
 328                         break;
 329
 330                 case 'k':
 331                         conf.http_keepalive = atoi(optarg);
 332                         break;
 333
 334                 case 'A':
 335                         conf.tcp_keepalive = atoi(optarg);
 336                         break;
 337
 338                 case 'f':
 339                         nofork = 1;
 340                         break;
 341
 342                 case 'd':
 343                         optarg = strdup(optarg);
 344                         port = alloca(strlen(optarg) + 1);
 345                         if (!port)
 346                                 return -1;
 347
 348                         /* "decode" plus to space to retain compat */
 349                         for (opt = 0; optarg[opt]; opt++)
 350                                 if (optarg[opt] == '+')
 351                                         optarg[opt] = ' ';
 352
 353                         /* opt now contains strlen(optarg) -- no need to re-scan */
 354                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 355                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 356                                 return -1;
 357                         }
 358
 359                         printf("%s", port);
 360                         return 0;
 361                         break;
 362
 363                 /* basic auth realm */
 364                 case 'r':
 365                         conf.realm = optarg;
 366                         break;
 367
 368                 /* md5 crypt */
 369                 case 'm':
 370                         printf("%s\n", crypt(optarg, "$1$"));
 371                         return 0;
 372                         break;
 373
 374                 /* config file */
 375                 case 'c':
 376                         conf.file = optarg;
 377                         break;
 378
 379 #ifdef HAVE_LUA
 380                 case 'l':
 381                         conf.lua_prefix = optarg;
 382                         break;
 383
 384                 case 'L':
 385                         conf.lua_handler = optarg;
 386                         break;
 387 #else
 388                 case 'l':
 389                 case 'L':
 390                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 391                                         "ignoring -%c\n", opt);
 392                         break;
 393 #endif
 394 #ifdef HAVE_UBUS
 395                 case 'a':
 396                         conf.ubus_noauth = 1;
 397                         break;
 398
 399                 case 'u':
 400                         conf.ubus_prefix = optarg;
 401                         break;
 402
 403                 case 'U':
 404                         conf.ubus_socket = optarg;
 405                         break;
 406
 407                 case 'X':
 408                         conf.ubus_cors = 1;
 409                         break;
 410 #else
 411                 case 'a':
 412                 case 'u':
 413                 case 'U':
 414                 case 'X':
 415                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 416                                         "ignoring -%c\n", opt);
 417                         break;
 418 #endif
 419                 default:
 420                         return usage(argv[0]);
 421                 }
 422         }
 423
 424         uh_config_parse();
 425
 426         if (!conf.docroot) {
 427                 if (!realpath(".", uh_buf)) {
 428                         fprintf(stderr, "Error: Unable to determine work dir\n");
 429                         return 1;
 430                 }
 431                 conf.docroot = strdup(uh_buf);
 432         }
 433
 434         init_defaults_post();
 435
 436         if (!bound) {
 437                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 438                 return 1;
 439         }
 440
 441 #ifdef HAVE_TLS
 442         if (n_tls) {
 443                 if (!tls_crt || !tls_key) {
 444                         fprintf(stderr, "Please specify a certificate and "
 445                                         "a key file to enable SSL support\n");
 446                         return 1;
 447                 }
 448
 449                 if (uh_tls_init(tls_key, tls_crt))
 450                     return 1;
 451         }
 452 #endif
 453
 454 #ifdef HAVE_LUA
 455         if (conf.lua_handler || conf.lua_prefix) {
 456                 if (!conf.lua_handler || !conf.lua_prefix) {
 457                         fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 458                         return 1;
 459                 }
 460                 if (uh_plugin_init("uhttpd_lua.so"))
 461                         return 1;
 462         }
 463 #endif
 464 #ifdef HAVE_UBUS
 465         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 466                 return 1;
 467 #endif
 468
 469         /* fork (if not disabled) */
 470         if (!nofork) {
 471                 switch (fork()) {
 472                 case -1:
 473                         perror("fork()");
 474                         exit(1);
 475
 476                 case 0:
 477                         /* daemon setup */
 478                         if (chdir("/"))
 479                                 perror("chdir()");
 480
 481                         cur_fd = open("/dev/null", O_WRONLY);
 482                         if (cur_fd > 0) {
 483                                 dup2(cur_fd, 0);
 484                                 dup2(cur_fd, 1);
 485                                 dup2(cur_fd, 2);
 486                         }
 487
 488                         break;
 489
 490                 default:
 491                         exit(0);
 492                 }
 493         }
 494
 495         return run_server();
 496 }