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
 107         s = strrchr(arg, ':');
 108         if (s) {
 109                 host = arg;
 110                 port = s + 1;
 111                 *s = 0;
 112         }
 113
 114         return uh_socket_bind(host, port, tls);
 115 }
 116
 117 static int usage(const char *name)
 118 {
 119         fprintf(stderr,
 120                 "Usage: %s -p [addr:]port -h docroot\n"
 121                 "       -f              Do not fork to background\n"
 122                 "       -c file         Configuration file, default is '/etc/httpd.conf'\n"
 123                 "       -p [addr:]port  Bind to specified address and port, multiple allowed\n"
 124 #ifdef HAVE_TLS
 125                 "       -s [addr:]port  Like -p but provide HTTPS on this port\n"
 126                 "       -C file         ASN.1 server certificate file\n"
 127                 "       -K file         ASN.1 server private key file\n"
 128 #endif
 129                 "       -h directory    Specify the document root, default is '.'\n"
 130                 "       -E string       Use given virtual URL as 404 error handler\n"
 131                 "       -I string       Use given filename as index for directories, multiple allowed\n"
 132                 "       -S              Do not follow symbolic links outside of the docroot\n"
 133                 "       -D              Do not allow directory listings, send 403 instead\n"
 134                 "       -R              Enable RFC1918 filter\n"
 135                 "       -n count        Maximum allowed number of concurrent script requests\n"
 136                 "       -N count        Maximum allowed number of concurrent connections\n"
 137 #ifdef HAVE_LUA
 138                 "       -l string       URL prefix for Lua handler, default is '/lua'\n"
 139                 "       -L file         Lua handler script, omit to disable Lua\n"
 140 #endif
 141 #ifdef HAVE_UBUS
 142                 "       -u string       URL prefix for HTTP/JSON handler\n"
 143                 "       -U file         Override ubus socket path\n"
 144 #endif
 145                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 146                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 147                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 148                 "       -T seconds      Network timeout in seconds, default is 30\n"
 149                 "       -k seconds              HTTP keepalive timeout\n"
 150                 "       -d string       URL decode given string\n"
 151                 "       -r string       Specify basic auth realm\n"
 152                 "       -m string       MD5 crypt given string\n"
 153                 "\n", name
 154         );
 155         return 1;
 156 }
 157
 158 static void init_defaults(void)
 159 {
 160         conf.script_timeout = 60;
 161         conf.network_timeout = 30;
 162         conf.http_keepalive = 20;
 163         conf.max_script_requests = 3;
 164         conf.max_connections = 100;
 165         conf.realm = "Protected Area";
 166         conf.cgi_prefix = "/cgi-bin";
 167         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 168
 169         uh_index_add("index.html");
 170         uh_index_add("index.htm");
 171         uh_index_add("default.html");
 172         uh_index_add("default.htm");
 173 }
 174
 175 static void fixup_prefix(char *str)
 176 {
 177         int len;
 178
 179         if (!str || !str[0])
 180                 return;
 181
 182         len = strlen(str) - 1;
 183
 184         while (len > 0 && str[len] == '/')
 185                 len--;
 186
 187         str[len + 1] = 0;
 188 }
 189
 190 int main(int argc, char **argv)
 191 {
 192         bool nofork = false;
 193         char *port;
 194         int opt, ch;
 195         int cur_fd;
 196         int bound = 0;
 197
 198 #ifdef HAVE_TLS
 199         int n_tls = 0;
 200         const char *tls_key = NULL, *tls_crt = NULL;
 201 #endif
 202
 203         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 204
 205         uh_dispatch_add(&cgi_dispatch);
 206         init_defaults();
 207         signal(SIGPIPE, SIG_IGN);
 208
 209         while ((ch = getopt(argc, argv, "fSDRC:K:E:I:p:s:h:c:l:L:d:r:m:n:N:x:i:t:k:T:A:u:U:")) != -1) {
 210                 switch(ch) {
 211 #ifdef HAVE_TLS
 212                 case 'C':
 213                         tls_crt = optarg;
 214                         break;
 215
 216                 case 'K':
 217                         tls_key = optarg;
 218                         break;
 219
 220                 case 's':
 221                         n_tls++;
 222                         /* fall through */
 223 #else
 224                 case 'C':
 225                 case 'K':
 226                 case 's':
 227                         fprintf(stderr, "uhttpd: TLS support not compiled, "
 228                                         "ignoring -%c\n", opt);
 229                         break;
 230 #endif
 231                 case 'p':
 232                         bound += add_listener_arg(optarg, (ch == 's'));
 233                         break;
 234
 235                 case 'h':
 236                         if (!realpath(optarg, uh_buf)) {
 237                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 238                                                 optarg, strerror(errno));
 239                                 exit(1);
 240                         }
 241                         conf.docroot = strdup(uh_buf);
 242                         break;
 243
 244                 case 'E':
 245                         if (optarg[0] != '/') {
 246                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 247                                                 optarg);
 248                                 exit(1);
 249                         }
 250                         conf.error_handler = optarg;
 251                         break;
 252
 253                 case 'I':
 254                         if (optarg[0] == '/') {
 255                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 256                                                 optarg);
 257                                 exit(1);
 258                         }
 259                         uh_index_add(optarg);
 260                         break;
 261
 262                 case 'S':
 263                         conf.no_symlinks = 1;
 264                         break;
 265
 266                 case 'D':
 267                         conf.no_dirlists = 1;
 268                         break;
 269
 270                 case 'R':
 271                         conf.rfc1918_filter = 1;
 272                         break;
 273
 274                 case 'n':
 275                         conf.max_script_requests = atoi(optarg);
 276                         break;
 277
 278                 case 'N':
 279                         conf.max_connections = atoi(optarg);
 280                         break;
 281
 282                 case 'x':
 283                         fixup_prefix(optarg);
 284                         conf.cgi_prefix = optarg;
 285                         break;
 286
 287                 case 'i':
 288                         port = strchr(optarg, '=');
 289                         if (optarg[0] != '.' || !port) {
 290                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 291                                                 optarg);
 292                                 exit(1);
 293                         }
 294
 295                         *port++ = 0;
 296                         uh_interpreter_add(optarg, port);
 297                         break;
 298
 299                 case 't':
 300                         conf.script_timeout = atoi(optarg);
 301                         break;
 302
 303                 case 'T':
 304                         conf.network_timeout = atoi(optarg);
 305                         break;
 306
 307                 case 'k':
 308                         conf.http_keepalive = atoi(optarg);
 309                         break;
 310
 311                 case 'A':
 312                         conf.tcp_keepalive = atoi(optarg);
 313                         break;
 314
 315                 case 'f':
 316                         nofork = 1;
 317                         break;
 318
 319                 case 'd':
 320                         port = alloca(strlen(optarg) + 1);
 321                         if (!port)
 322                                 return -1;
 323
 324                         /* "decode" plus to space to retain compat */
 325                         for (opt = 0; optarg[opt]; opt++)
 326                                 if (optarg[opt] == '+')
 327                                         optarg[opt] = ' ';
 328
 329                         /* opt now contains strlen(optarg) -- no need to re-scan */
 330                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 331                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 332                                 return -1;
 333                         }
 334
 335                         printf("%s", port);
 336                         break;
 337
 338                 /* basic auth realm */
 339                 case 'r':
 340                         conf.realm = optarg;
 341                         break;
 342
 343                 /* md5 crypt */
 344                 case 'm':
 345                         printf("%s\n", crypt(optarg, "$1$"));
 346                         return 0;
 347                         break;
 348
 349                 /* config file */
 350                 case 'c':
 351                         conf.file = optarg;
 352                         break;
 353
 354 #ifdef HAVE_LUA
 355                 case 'l':
 356                         conf.lua_prefix = optarg;
 357                         break;
 358
 359                 case 'L':
 360                         conf.lua_handler = optarg;
 361                         break;
 362 #else
 363                 case 'l':
 364                 case 'L':
 365                         fprintf(stderr, "uhttpd: Lua support not compiled, "
 366                                         "ignoring -%c\n", opt);
 367                         break;
 368 #endif
 369 #ifdef HAVE_UBUS
 370                 case 'u':
 371                         conf.ubus_prefix = optarg;
 372                         break;
 373
 374                 case 'U':
 375                         conf.ubus_socket = optarg;
 376                         break;
 377 #else
 378                 case 'u':
 379                 case 'U':
 380                         fprintf(stderr, "uhttpd: UBUS support not compiled, "
 381                                         "ignoring -%c\n", opt);
 382                         break;
 383 #endif
 384                 default:
 385                         return usage(argv[0]);
 386                 }
 387         }
 388
 389         uh_config_parse();
 390
 391         if (!bound) {
 392                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 393                 return 1;
 394         }
 395
 396 #ifdef HAVE_TLS
 397         if (n_tls) {
 398                 if (!tls_crt || !tls_key) {
 399                         fprintf(stderr, "Please specify a certificate and "
 400                                         "a key file to enable SSL support\n");
 401                         return 1;
 402                 }
 403
 404                 if (uh_tls_init(tls_key, tls_crt))
 405                     return 1;
 406         }
 407 #endif
 408
 409 #ifdef HAVE_LUA
 410         if (conf.lua_handler || conf.lua_prefix) {
 411                 if (!conf.lua_handler || !conf.lua_prefix) {
 412                         fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 413                         return 1;
 414                 }
 415                 if (uh_plugin_init("uhttpd_lua.so"))
 416                         return 1;
 417         }
 418 #endif
 419 #ifdef HAVE_UBUS
 420         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 421                 return 1;
 422 #endif
 423
 424         /* fork (if not disabled) */
 425         if (!nofork) {
 426                 switch (fork()) {
 427                 case -1:
 428                         perror("fork()");
 429                         exit(1);
 430
 431                 case 0:
 432                         /* daemon setup */
 433                         if (chdir("/"))
 434                                 perror("chdir()");
 435
 436                         cur_fd = open("/dev/null", O_WRONLY);
 437                         if (cur_fd > 0) {
 438                                 dup2(cur_fd, 0);
 439                                 dup2(cur_fd, 1);
 440                                 dup2(cur_fd, 2);
 441                         }
 442
 443                         break;
 444
 445                 default:
 446                         exit(0);
 447                 }
 448         }
 449
 450         return run_server();
 451 }