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         const char *tls_key = NULL, *tls_crt = NULL;
 193         bool nofork = false;
 194         char *port;
 195         int opt, ch;
 196         int cur_fd;
 197         int bound = 0;
 198         int n_tls = 0;
 199
 200         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 201
 202         uh_dispatch_add(&cgi_dispatch);
 203         init_defaults();
 204         signal(SIGPIPE, SIG_IGN);
 205
 206         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) {
 207                 bool tls = false;
 208
 209                 switch(ch) {
 210                 case 's':
 211                         n_tls++;
 212                         tls = true;
 213                         /* fall through */
 214                 case 'p':
 215                         bound += add_listener_arg(optarg, tls);
 216                         break;
 217
 218                 case 'h':
 219                         if (!realpath(optarg, uh_buf)) {
 220                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 221                                                 optarg, strerror(errno));
 222                                 exit(1);
 223                         }
 224                         conf.docroot = strdup(uh_buf);
 225                         break;
 226
 227                 case 'E':
 228                         if (optarg[0] != '/') {
 229                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 230                                                 optarg);
 231                                 exit(1);
 232                         }
 233                         conf.error_handler = optarg;
 234                         break;
 235
 236                 case 'I':
 237                         if (optarg[0] == '/') {
 238                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 239                                                 optarg);
 240                                 exit(1);
 241                         }
 242                         uh_index_add(optarg);
 243                         break;
 244
 245                 case 'S':
 246                         conf.no_symlinks = 1;
 247                         break;
 248
 249                 case 'D':
 250                         conf.no_dirlists = 1;
 251                         break;
 252
 253                 case 'R':
 254                         conf.rfc1918_filter = 1;
 255                         break;
 256
 257                 case 'n':
 258                         conf.max_script_requests = atoi(optarg);
 259                         break;
 260
 261                 case 'N':
 262                         conf.max_connections = atoi(optarg);
 263                         break;
 264
 265                 case 'x':
 266                         fixup_prefix(optarg);
 267                         conf.cgi_prefix = optarg;
 268                         break;
 269
 270                 case 'i':
 271                         port = strchr(optarg, '=');
 272                         if (optarg[0] != '.' || !port) {
 273                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 274                                                 optarg);
 275                                 exit(1);
 276                         }
 277
 278                         *port++ = 0;
 279                         uh_interpreter_add(optarg, port);
 280                         break;
 281
 282                 case 't':
 283                         conf.script_timeout = atoi(optarg);
 284                         break;
 285
 286                 case 'T':
 287                         conf.network_timeout = atoi(optarg);
 288                         break;
 289
 290                 case 'k':
 291                         conf.http_keepalive = atoi(optarg);
 292                         break;
 293
 294                 case 'A':
 295                         conf.tcp_keepalive = atoi(optarg);
 296                         break;
 297
 298                 case 'f':
 299                         nofork = 1;
 300                         break;
 301
 302                 case 'd':
 303                         port = alloca(strlen(optarg) + 1);
 304                         if (!port)
 305                                 return -1;
 306
 307                         /* "decode" plus to space to retain compat */
 308                         for (opt = 0; optarg[opt]; opt++)
 309                                 if (optarg[opt] == '+')
 310                                         optarg[opt] = ' ';
 311
 312                         /* opt now contains strlen(optarg) -- no need to re-scan */
 313                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 314                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 315                                 return -1;
 316                         }
 317
 318                         printf("%s", port);
 319                         break;
 320
 321                 /* basic auth realm */
 322                 case 'r':
 323                         conf.realm = optarg;
 324                         break;
 325
 326                 /* md5 crypt */
 327                 case 'm':
 328                         printf("%s\n", crypt(optarg, "$1$"));
 329                         return 0;
 330                         break;
 331
 332                 /* config file */
 333                 case 'c':
 334                         conf.file = optarg;
 335                         break;
 336
 337                 case 'C':
 338                         tls_crt = optarg;
 339                         break;
 340
 341                 case 'K':
 342                         tls_key = optarg;
 343                         break;
 344 #ifdef HAVE_LUA
 345                 case 'l':
 346                         conf.lua_prefix = optarg;
 347                         break;
 348
 349                 case 'L':
 350                         conf.lua_handler = optarg;
 351                         break;
 352 #endif
 353 #ifdef HAVE_UBUS
 354                 case 'u':
 355                         conf.ubus_prefix = optarg;
 356                         break;
 357
 358                 case 'U':
 359                         conf.ubus_socket = optarg;
 360                         break;
 361 #endif
 362                 default:
 363                         return usage(argv[0]);
 364                 }
 365         }
 366
 367         uh_config_parse();
 368
 369         if (!bound) {
 370                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 371                 return 1;
 372         }
 373
 374         if (n_tls) {
 375                 if (!tls_crt || !tls_key) {
 376                         fprintf(stderr, "Please specify a certificate and "
 377                                         "a key file to enable SSL support\n");
 378                         return 1;
 379                 }
 380
 381 #ifdef HAVE_TLS
 382                 if (uh_tls_init(tls_key, tls_crt))
 383                     return 1;
 384 #else
 385                 fprintf(stderr, "Error: TLS support not compiled in.\n");
 386                 return 1;
 387 #endif
 388         }
 389
 390 #ifdef HAVE_LUA
 391         if (conf.lua_handler || conf.lua_prefix) {
 392                 if (!conf.lua_handler || !conf.lua_prefix) {
 393                         fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 394                         return 1;
 395                 }
 396                 if (uh_plugin_init("uhttpd_lua.so"))
 397                         return 1;
 398         }
 399 #endif
 400 #ifdef HAVE_UBUS
 401         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 402                 return 1;
 403 #endif
 404
 405         /* fork (if not disabled) */
 406         if (!nofork) {
 407                 switch (fork()) {
 408                 case -1:
 409                         perror("fork()");
 410                         exit(1);
 411
 412                 case 0:
 413                         /* daemon setup */
 414                         if (chdir("/"))
 415                                 perror("chdir()");
 416
 417                         cur_fd = open("/dev/null", O_WRONLY);
 418                         if (cur_fd > 0) {
 419                                 dup2(cur_fd, 0);
 420                                 dup2(cur_fd, 1);
 421                                 dup2(cur_fd, 2);
 422                         }
 423
 424                         break;
 425
 426                 default:
 427                         exit(0);
 428                 }
 429         }
 430
 431         return run_server();
 432 }