networking/httpd.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * httpd implementation for busybox
   4  *
   5  * Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
   6  * Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   9  *
  10  *****************************************************************************
  11  *
  12  * Typical usage:
  13  * For non root user:
  14  *      httpd -p 8080 -h $HOME/public_html
  15  * For daemon start from rc script with uid=0:
  16  *      httpd -u www
  17  * which is equivalent to (assuming user www has uid 80):
  18  *      httpd -p 80 -u 80 -h $PWD -c /etc/httpd.conf -r "Web Server Authentication"
  19  *
  20  * When an url starts with "/cgi-bin/" it is assumed to be a cgi script.
  21  * The server changes directory to the location of the script and executes it
  22  * after setting QUERY_STRING and other environment variables.
  23  *
  24  * Doc:
  25  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
  26  *
  27  * The applet can also be invoked as an url arg decoder and html text encoder
  28  * as follows:
  29  *      foo=`httpd -d $foo`             # decode "Hello%20World" as "Hello World"
  30  *      bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
  31  * Note that url encoding for arguments is not the same as html encoding for
  32  * presentation.  -d decodes an url-encoded argument while -e encodes in html
  33  * for page display.
  34  *
  35  * httpd.conf has the following format:
  36  *
  37  * H:/serverroot     # define the server root. It will override -h
  38  * A:172.20.         # Allow address from 172.20.0.0/16
  39  * A:10.0.0.0/25     # Allow any address from 10.0.0.0-10.0.0.127
  40  * A:10.0.0.0/255.255.255.128  # Allow any address that previous set
  41  * A:127.0.0.1       # Allow local loopback connections
  42  * D:*               # Deny from other IP connections
  43  * E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
  44  * I:index.html      # Show index.html when a directory is requested
  45  *
  46  * P:/url:[http://]hostname[:port]/new/path
  47  *                   # When /urlXXXXXX is requested, reverse proxy
  48  *                   # it to http://hostname[:port]/new/pathXXXXXX
  49  *
  50  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
  51  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
  52  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
  53  * .au:audio/basic   # additional mime type for audio.au files
  54  * *.php:/path/php   # run xxx.php through an interpreter
  55  *
  56  * A/D may be as a/d or allow/deny - only first char matters.
  57  * Deny/Allow IP logic:
  58  *  - Default is to allow all (Allow all (A:*) is a no-op).
  59  *  - Deny rules take precedence over allow rules.
  60  *  - "Deny all" rule (D:*) is applied last.
  61  *
  62  * Example:
  63  *   1. Allow only specified addresses
  64  *     A:172.20          # Allow any address that begins with 172.20.
  65  *     A:10.10.          # Allow any address that begins with 10.10.
  66  *     A:127.0.0.1       # Allow local loopback connections
  67  *     D:*               # Deny from other IP connections
  68  *
  69  *   2. Only deny specified addresses
  70  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
  71  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
  72  *     A:*             # (optional line added for clarity)
  73  *
  74  * If a sub directory contains a config file it is parsed and merged with
  75  * any existing settings as if it was appended to the original configuration.
  76  *
  77  * subdir paths are relative to the containing subdir and thus cannot
  78  * affect the parent rules.
  79  *
  80  * Note that since the sub dir is parsed in the forked thread servicing the
  81  * subdir http request, any merge is discarded when the process exits.  As a
  82  * result, the subdir settings only have a lifetime of a single request.
  83  *
  84  * Custom error pages can contain an absolute path or be relative to
  85  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
  86  * page can only be defined in the root configuration file and are not taken
  87  * into account in local (directories) config files.
  88  *
  89  * If -c is not set, an attempt will be made to open the default
  90  * root configuration file.  If -c is set and the file is not found, the
  91  * server exits with an error.
  92  *
  93  */
  94  /* TODO: use TCP_CORK, parse_config() */
  95
  96 #include "libbb.h"
  97 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
  98 # include <sys/sendfile.h>
  99 #endif
 100 /* amount of buffering in a pipe */
 101 #ifndef PIPE_BUF
 102 # define PIPE_BUF 4096
 103 #endif
 104
 105 #define DEBUG 0
 106
 107 #define IOBUF_SIZE 8192
 108 #if PIPE_BUF >= IOBUF_SIZE
 109 # error "PIPE_BUF >= IOBUF_SIZE"
 110 #endif
 111
 112 #define HEADER_READ_TIMEOUT 60
 113
 114 static const char DEFAULT_PATH_HTTPD_CONF[] ALIGN1 = "/etc";
 115 static const char HTTPD_CONF[] ALIGN1 = "httpd.conf";
 116 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
 117 static const char index_html[] ALIGN1 = "index.html";
 118
 119 typedef struct has_next_ptr {
 120         struct has_next_ptr *next;
 121 } has_next_ptr;
 122
 123 /* Must have "next" as a first member */
 124 typedef struct Htaccess {
 125         struct Htaccess *next;
 126         char *after_colon;
 127         char before_colon[1];  /* really bigger, must be last */
 128 } Htaccess;
 129
 130 /* Must have "next" as a first member */
 131 typedef struct Htaccess_IP {
 132         struct Htaccess_IP *next;
 133         unsigned ip;
 134         unsigned mask;
 135         int allow_deny;
 136 } Htaccess_IP;
 137
 138 /* Must have "next" as a first member */
 139 typedef struct Htaccess_Proxy {
 140         struct Htaccess_Proxy *next;
 141         char *url_from;
 142         char *host_port;
 143         char *url_to;
 144 } Htaccess_Proxy;
 145
 146 enum {
 147         HTTP_OK = 200,
 148         HTTP_PARTIAL_CONTENT = 206,
 149         HTTP_MOVED_TEMPORARILY = 302,
 150         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
 151         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
 152         HTTP_NOT_FOUND = 404,
 153         HTTP_FORBIDDEN = 403,
 154         HTTP_REQUEST_TIMEOUT = 408,
 155         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
 156         HTTP_INTERNAL_SERVER_ERROR = 500,
 157         HTTP_CONTINUE = 100,
 158 #if 0   /* future use */
 159         HTTP_SWITCHING_PROTOCOLS = 101,
 160         HTTP_CREATED = 201,
 161         HTTP_ACCEPTED = 202,
 162         HTTP_NON_AUTHORITATIVE_INFO = 203,
 163         HTTP_NO_CONTENT = 204,
 164         HTTP_MULTIPLE_CHOICES = 300,
 165         HTTP_MOVED_PERMANENTLY = 301,
 166         HTTP_NOT_MODIFIED = 304,
 167         HTTP_PAYMENT_REQUIRED = 402,
 168         HTTP_BAD_GATEWAY = 502,
 169         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
 170 #endif
 171 };
 172
 173 static const uint16_t http_response_type[] ALIGN2 = {
 174         HTTP_OK,
 175 #if ENABLE_FEATURE_HTTPD_RANGES
 176         HTTP_PARTIAL_CONTENT,
 177 #endif
 178         HTTP_MOVED_TEMPORARILY,
 179         HTTP_REQUEST_TIMEOUT,
 180         HTTP_NOT_IMPLEMENTED,
 181 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 182         HTTP_UNAUTHORIZED,
 183 #endif
 184         HTTP_NOT_FOUND,
 185         HTTP_BAD_REQUEST,
 186         HTTP_FORBIDDEN,
 187         HTTP_INTERNAL_SERVER_ERROR,
 188 #if 0   /* not implemented */
 189         HTTP_CREATED,
 190         HTTP_ACCEPTED,
 191         HTTP_NO_CONTENT,
 192         HTTP_MULTIPLE_CHOICES,
 193         HTTP_MOVED_PERMANENTLY,
 194         HTTP_NOT_MODIFIED,
 195         HTTP_BAD_GATEWAY,
 196         HTTP_SERVICE_UNAVAILABLE,
 197 #endif
 198 };
 199
 200 static const struct {
 201         const char *name;
 202         const char *info;
 203 } http_response[ARRAY_SIZE(http_response_type)] = {
 204         { "OK", NULL },
 205 #if ENABLE_FEATURE_HTTPD_RANGES
 206         { "Partial Content", NULL },
 207 #endif
 208         { "Found", NULL },
 209         { "Request Timeout", "No request appeared within 60 seconds" },
 210         { "Not Implemented", "The requested method is not recognized" },
 211 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 212         { "Unauthorized", "" },
 213 #endif
 214         { "Not Found", "The requested URL was not found" },
 215         { "Bad Request", "Unsupported method" },
 216         { "Forbidden", ""  },
 217         { "Internal Server Error", "Internal Server Error" },
 218 #if 0   /* not implemented */
 219         { "Created" },
 220         { "Accepted" },
 221         { "No Content" },
 222         { "Multiple Choices" },
 223         { "Moved Permanently" },
 224         { "Not Modified" },
 225         { "Bad Gateway", "" },
 226         { "Service Unavailable", "" },
 227 #endif
 228 };
 229
 230 struct globals {
 231         int verbose;            /* must be int (used by getopt32) */
 232         smallint flg_deny_all;
 233
 234         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
 235         time_t last_mod;
 236         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
 237         const char *bind_addr_or_port;
 238
 239         const char *g_query;
 240         const char *opt_c_configFile;
 241         const char *home_httpd;
 242         const char *index_page;
 243
 244         const char *found_mime_type;
 245         const char *found_moved_temporarily;
 246         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 247
 248         IF_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
 249         IF_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
 250         IF_FEATURE_HTTPD_CGI(char *referer;)
 251         IF_FEATURE_HTTPD_CGI(char *user_agent;)
 252         IF_FEATURE_HTTPD_CGI(char *host;)
 253         IF_FEATURE_HTTPD_CGI(char *http_accept;)
 254         IF_FEATURE_HTTPD_CGI(char *http_accept_language;)
 255
 256         off_t file_size;        /* -1 - unknown */
 257 #if ENABLE_FEATURE_HTTPD_RANGES
 258         off_t range_start;
 259         off_t range_end;
 260         off_t range_len;
 261 #endif
 262
 263 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 264         Htaccess *g_auth;       /* config user:password lines */
 265 #endif
 266         Htaccess *mime_a;       /* config mime types */
 267 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 268         Htaccess *script_i;     /* config script interpreters */
 269 #endif
 270         char *iobuf;            /* [IOBUF_SIZE] */
 271 #define hdr_buf bb_common_bufsiz1
 272         char *hdr_ptr;
 273         int hdr_cnt;
 274 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 275         const char *http_error_page[ARRAY_SIZE(http_response_type)];
 276 #endif
 277 #if ENABLE_FEATURE_HTTPD_PROXY
 278         Htaccess_Proxy *proxy;
 279 #endif
 280 };
 281 #define G (*ptr_to_globals)
 282 #define verbose           (G.verbose          )
 283 #define flg_deny_all      (G.flg_deny_all     )
 284 #define rmt_ip            (G.rmt_ip           )
 285 #define bind_addr_or_port (G.bind_addr_or_port)
 286 #define g_query           (G.g_query          )
 287 #define opt_c_configFile  (G.opt_c_configFile )
 288 #define home_httpd        (G.home_httpd       )
 289 #define index_page        (G.index_page       )
 290 #define found_mime_type   (G.found_mime_type  )
 291 #define found_moved_temporarily (G.found_moved_temporarily)
 292 #define last_mod          (G.last_mod         )
 293 #define ip_a_d            (G.ip_a_d           )
 294 #define g_realm           (G.g_realm          )
 295 #define remoteuser        (G.remoteuser       )
 296 #define referer           (G.referer          )
 297 #define user_agent        (G.user_agent       )
 298 #define host              (G.host             )
 299 #define http_accept       (G.http_accept      )
 300 #define http_accept_language (G.http_accept_language)
 301 #define file_size         (G.file_size        )
 302 #if ENABLE_FEATURE_HTTPD_RANGES
 303 #define range_start       (G.range_start      )
 304 #define range_end         (G.range_end        )
 305 #define range_len         (G.range_len        )
 306 #else
 307 enum {
 308         range_start = 0,
 309         range_end = MAXINT(off_t) - 1,
 310         range_len = MAXINT(off_t),
 311 };
 312 #endif
 313 #define rmt_ip_str        (G.rmt_ip_str       )
 314 #define g_auth            (G.g_auth           )
 315 #define mime_a            (G.mime_a           )
 316 #define script_i          (G.script_i         )
 317 #define iobuf             (G.iobuf            )
 318 #define hdr_ptr           (G.hdr_ptr          )
 319 #define hdr_cnt           (G.hdr_cnt          )
 320 #define http_error_page   (G.http_error_page  )
 321 #define proxy             (G.proxy            )
 322 #define INIT_G() do { \
 323         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 324         IF_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
 325         bind_addr_or_port = "80"; \
 326         index_page = index_html; \
 327         file_size = -1; \
 328 } while (0)
 329
 330
 331 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
 332
 333 /* Prototypes */
 334 enum {
 335         SEND_HEADERS     = (1 << 0),
 336         SEND_BODY        = (1 << 1),
 337         SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
 338 };
 339 static void send_file_and_exit(const char *url, int what) NORETURN;
 340
 341 static void free_llist(has_next_ptr **pptr)
 342 {
 343         has_next_ptr *cur = *pptr;
 344         while (cur) {
 345                 has_next_ptr *t = cur;
 346                 cur = cur->next;
 347                 free(t);
 348         }
 349         *pptr = NULL;
 350 }
 351
 352 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 353 {
 354         free_llist((has_next_ptr**)pptr);
 355 }
 356
 357 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 358 {
 359         free_llist((has_next_ptr**)pptr);
 360 }
 361
 362 /* Returns presumed mask width in bits or < 0 on error.
 363  * Updates strp, stores IP at provided pointer */
 364 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 365 {
 366         const char *p = *strp;
 367         int auto_mask = 8;
 368         unsigned ip = 0;
 369         int j;
 370
 371         if (*p == '/')
 372                 return -auto_mask;
 373
 374         for (j = 0; j < 4; j++) {
 375                 unsigned octet;
 376
 377                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
 378                         return -auto_mask;
 379                 octet = 0;
 380                 while (*p >= '0' && *p <= '9') {
 381                         octet *= 10;
 382                         octet += *p - '0';
 383                         if (octet > 255)
 384                                 return -auto_mask;
 385                         p++;
 386                 }
 387                 if (*p == '.')
 388                         p++;
 389                 if (*p != '/' && *p)
 390                         auto_mask += 8;
 391                 ip = (ip << 8) | octet;
 392         }
 393         if (*p) {
 394                 if (*p != endc)
 395                         return -auto_mask;
 396                 p++;
 397                 if (*p == '\0')
 398                         return -auto_mask;
 399         }
 400         *ipp = ip;
 401         *strp = p;
 402         return auto_mask;
 403 }
 404
 405 /* Returns 0 on success. Stores IP and mask at provided pointers */
 406 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 407 {
 408         int i;
 409         unsigned mask;
 410         char *p;
 411
 412         i = scan_ip(&str, ipp, '/');
 413         if (i < 0)
 414                 return i;
 415
 416         if (*str) {
 417                 /* there is /xxx after dotted-IP address */
 418                 i = bb_strtou(str, &p, 10);
 419                 if (*p == '.') {
 420                         /* 'xxx' itself is dotted-IP mask, parse it */
 421                         /* (return 0 (success) only if it has N.N.N.N form) */
 422                         return scan_ip(&str, maskp, '\0') - 32;
 423                 }
 424                 if (*p)
 425                         return -1;
 426         }
 427
 428         if (i > 32)
 429                 return -1;
 430
 431         if (sizeof(unsigned) == 4 && i == 32) {
 432                 /* mask >>= 32 below may not work */
 433                 mask = 0;
 434         } else {
 435                 mask = 0xffffffff;
 436                 mask >>= i;
 437         }
 438         /* i == 0 -> *maskp = 0x00000000
 439          * i == 1 -> *maskp = 0x80000000
 440          * i == 4 -> *maskp = 0xf0000000
 441          * i == 31 -> *maskp = 0xfffffffe
 442          * i == 32 -> *maskp = 0xffffffff */
 443         *maskp = (uint32_t)(~mask);
 444         return 0;
 445 }
 446
 447 /*
 448  * Parse configuration file into in-memory linked list.
 449  *
 450  * Any previous IP rules are discarded.
 451  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
 452  * are also discarded.  That is, previous settings are retained if flag is
 453  * SUBDIR_PARSE.
 454  * Error pages are only parsed on the main config file.
 455  *
 456  * path   Path where to look for httpd.conf (without filename).
 457  * flag   Type of the parse request.
 458  */
 459 /* flag param: */
 460 enum {
 461         FIRST_PARSE    = 0, /* path will be "/etc" */
 462         SIGNALED_PARSE = 1, /* path will be "/etc" */
 463         SUBDIR_PARSE   = 2, /* path will be derived from URL */
 464 };
 465 static void parse_conf(const char *path, int flag)
 466 {
 467         /* internally used extra flag state */
 468         enum { TRY_CURDIR_PARSE = 3 };
 469
 470         FILE *f;
 471         const char *filename;
 472         char buf[160];
 473
 474         /* discard old rules */
 475         free_Htaccess_IP_list(&ip_a_d);
 476         flg_deny_all = 0;
 477         /* retain previous auth and mime config only for subdir parse */
 478         if (flag != SUBDIR_PARSE) {
 479                 free_Htaccess_list(&mime_a);
 480 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 481                 free_Htaccess_list(&g_auth);
 482 #endif
 483 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 484                 free_Htaccess_list(&script_i);
 485 #endif
 486         }
 487
 488         filename = opt_c_configFile;
 489         if (flag == SUBDIR_PARSE || filename == NULL) {
 490                 filename = alloca(strlen(path) + sizeof(HTTPD_CONF) + 2);
 491                 sprintf((char *)filename, "%s/%s", path, HTTPD_CONF);
 492         }
 493
 494         while ((f = fopen_for_read(filename)) == NULL) {
 495                 if (flag >= SUBDIR_PARSE) { /* SUBDIR or TRY_CURDIR */
 496                         /* config file not found, no changes to config */
 497                         return;
 498                 }
 499                 if (flag == FIRST_PARSE) {
 500                         /* -c CONFFILE given, but CONFFILE doesn't exist? */
 501                         if (opt_c_configFile)
 502                                 bb_simple_perror_msg_and_die(opt_c_configFile);
 503                         /* else: no -c, thus we looked at /etc/httpd.conf,
 504                          * and it's not there. try ./httpd.conf: */
 505                 }
 506                 flag = TRY_CURDIR_PARSE;
 507                 filename = HTTPD_CONF;
 508         }
 509
 510 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 511         /* in "/file:user:pass" lines, we prepend path in subdirs */
 512         if (flag != SUBDIR_PARSE)
 513                 path = "";
 514 #endif
 515         /* The lines can be:
 516          *
 517          * I:default_index_file
 518          * H:http_home
 519          * [AD]:IP[/mask]   # allow/deny, * for wildcard
 520          * Ennn:error.html  # error page for status nnn
 521          * P:/url:[http://]hostname[:port]/new/path # reverse proxy
 522          * .ext:mime/type   # mime type
 523          * *.php:/path/php  # run xxx.php through an interpreter
 524          * /file:user:pass  # username and password
 525          */
 526         while (fgets(buf, sizeof(buf), f) != NULL) {
 527                 unsigned strlen_buf;
 528                 unsigned char ch;
 529                 char *after_colon;
 530
 531                 { /* remove all whitespace, and # comments */
 532                         char *p, *p0;
 533
 534                         p0 = buf;
 535                         /* skip non-whitespace beginning. Often the whole line
 536                          * is non-whitespace. We want this case to work fast,
 537                          * without needless copying, therefore we don't merge
 538                          * this operation into next while loop. */
 539                         while ((ch = *p0) != '\0' && ch != '\n' && ch != '#'
 540                          && ch != ' ' && ch != '\t'
 541                         ) {
 542                                 p0++;
 543                         }
 544                         p = p0;
 545                         /* if we enter this loop, we have some whitespace.
 546                          * discard it */
 547                         while (ch != '\0' && ch != '\n' && ch != '#') {
 548                                 if (ch != ' ' && ch != '\t') {
 549                                         *p++ = ch;
 550                                 }
 551                                 ch = *++p0;
 552                         }
 553                         *p = '\0';
 554                         strlen_buf = p - buf;
 555                         if (strlen_buf == 0)
 556                                 continue; /* empty line */
 557                 }
 558
 559                 after_colon = strchr(buf, ':');
 560                 /* strange line? */
 561                 if (after_colon == NULL || *++after_colon == '\0')
 562                         goto config_error;
 563
 564                 ch = (buf[0] & ~0x20); /* toupper if it's a letter */
 565
 566                 if (ch == 'I') {
 567                         if (index_page != index_html)
 568                                 free((char*)index_page);
 569                         index_page = xstrdup(after_colon);
 570                         continue;
 571                 }
 572
 573                 /* do not allow jumping around using H in subdir's configs */
 574                 if (flag == FIRST_PARSE && ch == 'H') {
 575                         home_httpd = xstrdup(after_colon);
 576                         xchdir(home_httpd);
 577                         continue;
 578                 }
 579
 580                 if (ch == 'A' || ch == 'D') {
 581                         Htaccess_IP *pip;
 582
 583                         if (*after_colon == '*') {
 584                                 if (ch == 'D') {
 585                                         /* memorize "deny all" */
 586                                         flg_deny_all = 1;
 587                                 }
 588                                 /* skip assumed "A:*", it is a default anyway */
 589                                 continue;
 590                         }
 591                         /* store "allow/deny IP/mask" line */
 592                         pip = xzalloc(sizeof(*pip));
 593                         if (scan_ip_mask(after_colon, &pip->ip, &pip->mask)) {
 594                                 /* IP{/mask} syntax error detected, protect all */
 595                                 ch = 'D';
 596                                 pip->mask = 0;
 597                         }
 598                         pip->allow_deny = ch;
 599                         if (ch == 'D') {
 600                                 /* Deny:from_IP - prepend */
 601                                 pip->next = ip_a_d;
 602                                 ip_a_d = pip;
 603                         } else {
 604                                 /* A:from_IP - append (thus all D's precedes A's) */
 605                                 Htaccess_IP *prev_IP = ip_a_d;
 606                                 if (prev_IP == NULL) {
 607                                         ip_a_d = pip;
 608                                 } else {
 609                                         while (prev_IP->next)
 610                                                 prev_IP = prev_IP->next;
 611                                         prev_IP->next = pip;
 612                                 }
 613                         }
 614                         continue;
 615                 }
 616
 617 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 618                 if (flag == FIRST_PARSE && ch == 'E') {
 619                         unsigned i;
 620                         int status = atoi(buf + 1); /* error status code */
 621
 622                         if (status < HTTP_CONTINUE) {
 623                                 goto config_error;
 624                         }
 625                         /* then error page; find matching status */
 626                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 627                                 if (http_response_type[i] == status) {
 628                                         /* We chdir to home_httpd, thus no need to
 629                                          * concat_path_file(home_httpd, after_colon)
 630                                          * here */
 631                                         http_error_page[i] = xstrdup(after_colon);
 632                                         break;
 633                                 }
 634                         }
 635                         continue;
 636                 }
 637 #endif
 638
 639 #if ENABLE_FEATURE_HTTPD_PROXY
 640                 if (flag == FIRST_PARSE && ch == 'P') {
 641                         /* P:/url:[http://]hostname[:port]/new/path */
 642                         char *url_from, *host_port, *url_to;
 643                         Htaccess_Proxy *proxy_entry;
 644
 645                         url_from = after_colon;
 646                         host_port = strchr(after_colon, ':');
 647                         if (host_port == NULL) {
 648                                 goto config_error;
 649                         }
 650                         *host_port++ = '\0';
 651                         if (strncmp(host_port, "http://", 7) == 0)
 652                                 host_port += 7;
 653                         if (*host_port == '\0') {
 654                                 goto config_error;
 655                         }
 656                         url_to = strchr(host_port, '/');
 657                         if (url_to == NULL) {
 658                                 goto config_error;
 659                         }
 660                         *url_to = '\0';
 661                         proxy_entry = xzalloc(sizeof(*proxy_entry));
 662                         proxy_entry->url_from = xstrdup(url_from);
 663                         proxy_entry->host_port = xstrdup(host_port);
 664                         *url_to = '/';
 665                         proxy_entry->url_to = xstrdup(url_to);
 666                         proxy_entry->next = proxy;
 667                         proxy = proxy_entry;
 668                         continue;
 669                 }
 670 #endif
 671                 /* the rest of directives are non-alphabetic,
 672                  * must avoid using "toupper'ed" ch */
 673                 ch = buf[0];
 674
 675                 if (ch == '.' /* ".ext:mime/type" */
 676 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 677                  || (ch == '*' && buf[1] == '.') /* "*.php:/path/php" */
 678 #endif
 679                 ) {
 680                         char *p;
 681                         Htaccess *cur;
 682
 683                         cur = xzalloc(sizeof(*cur) /* includes space for NUL */ + strlen_buf);
 684                         strcpy(cur->before_colon, buf);
 685                         p = cur->before_colon + (after_colon - buf);
 686                         p[-1] = '\0';
 687                         cur->after_colon = p;
 688                         if (ch == '.') {
 689                                 /* .mime line: prepend to mime_a list */
 690                                 cur->next = mime_a;
 691                                 mime_a = cur;
 692                         }
 693 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 694                         else {
 695                                 /* script interpreter line: prepend to script_i list */
 696                                 cur->next = script_i;
 697                                 script_i = cur;
 698                         }
 699 #endif
 700                         continue;
 701                 }
 702
 703 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 704                 if (ch == '/') { /* "/file:user:pass" */
 705                         char *p;
 706                         Htaccess *cur;
 707                         unsigned file_len;
 708
 709                         /* note: path is "" unless we are in SUBDIR parse,
 710                          * otherwise it does NOT start with "/" */
 711                         cur = xzalloc(sizeof(*cur) /* includes space for NUL */
 712                                 + 1 + strlen(path)
 713                                 + strlen_buf
 714                                 );
 715                         /* form "/path/file" */
 716                         sprintf(cur->before_colon, "/%s%.*s",
 717                                 path,
 718                                 (int) (after_colon - buf - 1), /* includes "/", but not ":" */
 719                                 buf);
 720                         /* canonicalize it */
 721                         p = bb_simplify_abs_path_inplace(cur->before_colon);
 722                         file_len = p - cur->before_colon;
 723                         /* add "user:pass" after NUL */
 724                         strcpy(++p, after_colon);
 725                         cur->after_colon = p;
 726
 727                         /* insert cur into g_auth */
 728                         /* g_auth is sorted by decreased filename length */
 729                         {
 730                                 Htaccess *auth, **authp;
 731
 732                                 authp = &g_auth;
 733                                 while ((auth = *authp) != NULL) {
 734                                         if (file_len >= strlen(auth->before_colon)) {
 735                                                 /* insert cur before auth */
 736                                                 cur->next = auth;
 737                                                 break;
 738                                         }
 739                                         authp = &auth->next;
 740                                 }
 741                                 *authp = cur;
 742                         }
 743                         continue;
 744                 }
 745 #endif /* BASIC_AUTH */
 746
 747                 /* the line is not recognized */
 748  config_error:
 749                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 750          } /* while (fgets) */
 751
 752          fclose(f);
 753 }
 754
 755 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
 756 /*
 757  * Given a string, html-encode special characters.
 758  * This is used for the -e command line option to provide an easy way
 759  * for scripts to encode result data without confusing browsers.  The
 760  * returned string pointer is memory allocated by malloc().
 761  *
 762  * Returns a pointer to the encoded string (malloced).
 763  */
 764 static char *encodeString(const char *string)
 765 {
 766         /* take the simple route and encode everything */
 767         /* could possibly scan once to get length.     */
 768         int len = strlen(string);
 769         char *out = xmalloc(len * 6 + 1);
 770         char *p = out;
 771         char ch;
 772
 773         while ((ch = *string++) != '\0') {
 774                 /* very simple check for what to encode */
 775                 if (isalnum(ch))
 776                         *p++ = ch;
 777                 else
 778                         p += sprintf(p, "&#%d;", (unsigned char) ch);
 779         }
 780         *p = '\0';
 781         return out;
 782 }
 783 #endif
 784
 785 /*
 786  * Given a URL encoded string, convert it to plain ascii.
 787  * Since decoding always makes strings smaller, the decode is done in-place.
 788  * Thus, callers should xstrdup() the argument if they do not want the
 789  * argument modified.  The return is the original pointer, allowing this
 790  * function to be easily used as arguments to other functions.
 791  *
 792  * string    The first string to decode.
 793  * option_d  1 if called for httpd -d
 794  *
 795  * Returns a pointer to the decoded string (same as input).
 796  */
 797 static unsigned hex_to_bin(unsigned char c)
 798 {
 799         unsigned v;
 800
 801         v = c - '0';
 802         if (v <= 9)
 803                 return v;
 804         /* c | 0x20: letters to lower case, non-letters
 805          * to (potentially different) non-letters */
 806         v = (unsigned)(c | 0x20) - 'a';
 807         if (v <= 5)
 808                 return v + 10;
 809         return ~0;
 810 /* For testing:
 811 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
 812 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 813 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 814 */
 815 }
 816 static char *decodeString(char *orig, int option_d)
 817 {
 818         /* note that decoded string is always shorter than original */
 819         char *string = orig;
 820         char *ptr = string;
 821         char c;
 822
 823         while ((c = *ptr++) != '\0') {
 824                 unsigned v;
 825
 826                 if (option_d && c == '+') {
 827                         *string++ = ' ';
 828                         continue;
 829                 }
 830                 if (c != '%') {
 831                         *string++ = c;
 832                         continue;
 833                 }
 834                 v = hex_to_bin(ptr[0]);
 835                 if (v > 15) {
 836  bad_hex:
 837                         if (!option_d)
 838                                 return NULL;
 839                         *string++ = '%';
 840                         continue;
 841                 }
 842                 v = (v * 16) | hex_to_bin(ptr[1]);
 843                 if (v > 255)
 844                         goto bad_hex;
 845                 if (!option_d && (v == '/' || v == '\0')) {
 846                         /* caller takes it as indication of invalid
 847                          * (dangerous wrt exploits) chars */
 848                         return orig + 1;
 849                 }
 850                 *string++ = v;
 851                 ptr += 2;
 852         }
 853         *string = '\0';
 854         return orig;
 855 }
 856
 857 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 858 /*
 859  * Decode a base64 data stream as per rfc1521.
 860  * Note that the rfc states that non base64 chars are to be ignored.
 861  * Since the decode always results in a shorter size than the input,
 862  * it is OK to pass the input arg as an output arg.
 863  * Parameter: a pointer to a base64 encoded string.
 864  * Decoded data is stored in-place.
 865  */
 866 static void decodeBase64(char *Data)
 867 {
 868         const unsigned char *in = (const unsigned char *)Data;
 869         /* The decoded size will be at most 3/4 the size of the encoded */
 870         unsigned ch = 0;
 871         int i = 0;
 872
 873         while (*in) {
 874                 int t = *in++;
 875
 876                 if (t >= '0' && t <= '9')
 877                         t = t - '0' + 52;
 878                 else if (t >= 'A' && t <= 'Z')
 879                         t = t - 'A';
 880                 else if (t >= 'a' && t <= 'z')
 881                         t = t - 'a' + 26;
 882                 else if (t == '+')
 883                         t = 62;
 884                 else if (t == '/')
 885                         t = 63;
 886                 else if (t == '=')
 887                         t = 0;
 888                 else
 889                         continue;
 890
 891                 ch = (ch << 6) | t;
 892                 i++;
 893                 if (i == 4) {
 894                         *Data++ = (char) (ch >> 16);
 895                         *Data++ = (char) (ch >> 8);
 896                         *Data++ = (char) ch;
 897                         i = 0;
 898                 }
 899         }
 900         *Data = '\0';
 901 }
 902 #endif
 903
 904 /*
 905  * Create a listen server socket on the designated port.
 906  */
 907 static int openServer(void)
 908 {
 909         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 910         if (!errno && n && n <= 0xffff)
 911                 n = create_and_bind_stream_or_die(NULL, n);
 912         else
 913                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 914         xlisten(n, 9);
 915         return n;
 916 }
 917
 918 /*
 919  * Log the connection closure and exit.
 920  */
 921 static void log_and_exit(void) NORETURN;
 922 static void log_and_exit(void)
 923 {
 924         /* Paranoia. IE said to be buggy. It may send some extra data
 925          * or be confused by us just exiting without SHUT_WR. Oh well. */
 926         shutdown(1, SHUT_WR);
 927         /* Why??
 928         (this also messes up stdin when user runs httpd -i from terminal)
 929         ndelay_on(0);
 930         while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
 931                 continue;
 932         */
 933
 934         if (verbose > 2)
 935                 bb_error_msg("closed");
 936         _exit(xfunc_error_retval);
 937 }
 938
 939 /*
 940  * Create and send HTTP response headers.
 941  * The arguments are combined and sent as one write operation.  Note that
 942  * IE will puke big-time if the headers are not sent in one packet and the
 943  * second packet is delayed for any reason.
 944  * responseNum - the result code to send.
 945  */
 946 static void send_headers(int responseNum)
 947 {
 948         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 949
 950         const char *responseString = "";
 951         const char *infoString = NULL;
 952         const char *mime_type;
 953 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 954         const char *error_page = NULL;
 955 #endif
 956         unsigned i;
 957         time_t timer = time(NULL);
 958         char tmp_str[80];
 959         int len;
 960
 961         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 962                 if (http_response_type[i] == responseNum) {
 963                         responseString = http_response[i].name;
 964                         infoString = http_response[i].info;
 965 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 966                         error_page = http_error_page[i];
 967 #endif
 968                         break;
 969                 }
 970         }
 971         /* error message is HTML */
 972         mime_type = responseNum == HTTP_OK ?
 973                                 found_mime_type : "text/html";
 974
 975         if (verbose)
 976                 bb_error_msg("response:%u", responseNum);
 977
 978         /* emit the current date */
 979         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
 980         len = sprintf(iobuf,
 981                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
 982                         "Date: %s\r\nConnection: close\r\n",
 983                         responseNum, responseString, mime_type, tmp_str);
 984
 985 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 986         if (responseNum == HTTP_UNAUTHORIZED) {
 987                 len += sprintf(iobuf + len,
 988                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
 989                                 g_realm);
 990         }
 991 #endif
 992         if (responseNum == HTTP_MOVED_TEMPORARILY) {
 993                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
 994                                 found_moved_temporarily,
 995                                 (g_query ? "?" : ""),
 996                                 (g_query ? g_query : ""));
 997         }
 998
 999 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1000         if (error_page && access(error_page, R_OK) == 0) {
1001                 strcat(iobuf, "\r\n");
1002                 len += 2;
1003
1004                 if (DEBUG)
1005                         fprintf(stderr, "headers: '%s'\n", iobuf);
1006                 full_write(STDOUT_FILENO, iobuf, len);
1007                 if (DEBUG)
1008                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1009                 return send_file_and_exit(error_page, SEND_BODY);
1010         }
1011 #endif
1012
1013         if (file_size != -1) {    /* file */
1014                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1015 #if ENABLE_FEATURE_HTTPD_RANGES
1016                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1017                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"u-%"OFF_FMT"u/%"OFF_FMT"u\r\n",
1018                                         range_start,
1019                                         range_end,
1020                                         file_size);
1021                         file_size = range_end - range_start + 1;
1022                 }
1023 #endif
1024                 len += sprintf(iobuf + len,
1025 #if ENABLE_FEATURE_HTTPD_RANGES
1026                         "Accept-Ranges: bytes\r\n"
1027 #endif
1028                         "Last-Modified: %s\r\n%s %"OFF_FMT"u\r\n",
1029                                 tmp_str,
1030                                 "Content-length:",
1031                                 file_size
1032                 );
1033         }
1034         iobuf[len++] = '\r';
1035         iobuf[len++] = '\n';
1036         if (infoString) {
1037                 len += sprintf(iobuf + len,
1038                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1039                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1040                                 responseNum, responseString,
1041                                 responseNum, responseString, infoString);
1042         }
1043         if (DEBUG)
1044                 fprintf(stderr, "headers: '%s'\n", iobuf);
1045         if (full_write(STDOUT_FILENO, iobuf, len) != len) {
1046                 if (verbose > 1)
1047                         bb_perror_msg("error");
1048                 log_and_exit();
1049         }
1050 }
1051
1052 static void send_headers_and_exit(int responseNum) NORETURN;
1053 static void send_headers_and_exit(int responseNum)
1054 {
1055         send_headers(responseNum);
1056         log_and_exit();
1057 }
1058
1059 /*
1060  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1061  * '\n' is replaced with NUL.
1062  * Return number of characters read or 0 if nothing is read
1063  * ('\r' and '\n' are not counted).
1064  * Data is returned in iobuf.
1065  */
1066 static int get_line(void)
1067 {
1068         int count = 0;
1069         char c;
1070
1071         alarm(HEADER_READ_TIMEOUT);
1072         while (1) {
1073                 if (hdr_cnt <= 0) {
1074                         hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1075                         if (hdr_cnt <= 0)
1076                                 break;
1077                         hdr_ptr = hdr_buf;
1078                 }
1079                 iobuf[count] = c = *hdr_ptr++;
1080                 hdr_cnt--;
1081
1082                 if (c == '\r')
1083                         continue;
1084                 if (c == '\n') {
1085                         iobuf[count] = '\0';
1086                         break;
1087                 }
1088                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1089                         count++;
1090         }
1091         return count;
1092 }
1093
1094 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1095
1096 /* gcc 4.2.1 fares better with NOINLINE */
1097 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
1098 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1099 {
1100         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1101         struct pollfd pfd[3];
1102         int out_cnt; /* we buffer a bit of initial CGI output */
1103         int count;
1104
1105         /* iobuf is used for CGI -> network data,
1106          * hdr_buf is for network -> CGI data (POSTDATA) */
1107
1108         /* If CGI dies, we still want to correctly finish reading its output
1109          * and send it to the peer. So please no SIGPIPEs! */
1110         signal(SIGPIPE, SIG_IGN);
1111
1112         // We inconsistently handle a case when more POSTDATA from network
1113         // is coming than we expected. We may give *some part* of that
1114         // extra data to CGI.
1115
1116         //if (hdr_cnt > post_len) {
1117         //      /* We got more POSTDATA from network than we expected */
1118         //      hdr_cnt = post_len;
1119         //}
1120         post_len -= hdr_cnt;
1121         /* post_len - number of POST bytes not yet read from network */
1122
1123         /* NB: breaking out of this loop jumps to log_and_exit() */
1124         out_cnt = 0;
1125         while (1) {
1126                 memset(pfd, 0, sizeof(pfd));
1127
1128                 pfd[FROM_CGI].fd = fromCgi_rd;
1129                 pfd[FROM_CGI].events = POLLIN;
1130
1131                 if (toCgi_wr) {
1132                         pfd[TO_CGI].fd = toCgi_wr;
1133                         if (hdr_cnt > 0) {
1134                                 pfd[TO_CGI].events = POLLOUT;
1135                         } else if (post_len > 0) {
1136                                 pfd[0].events = POLLIN;
1137                         } else {
1138                                 /* post_len <= 0 && hdr_cnt <= 0:
1139                                  * no more POST data to CGI,
1140                                  * let CGI see EOF on CGI's stdin */
1141                                 if (toCgi_wr != fromCgi_rd)
1142                                         close(toCgi_wr);
1143                                 toCgi_wr = 0;
1144                         }
1145                 }
1146
1147                 /* Now wait on the set of sockets */
1148                 count = safe_poll(pfd, toCgi_wr ? TO_CGI+1 : FROM_CGI+1, -1);
1149                 if (count <= 0) {
1150 #if 0
1151                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1152                                 /* Weird. CGI didn't exit and no fd's
1153                                  * are ready, yet poll returned?! */
1154                                 continue;
1155                         }
1156                         if (DEBUG && WIFEXITED(status))
1157                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1158                         if (DEBUG && WIFSIGNALED(status))
1159                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1160 #endif
1161                         break;
1162                 }
1163
1164                 if (pfd[TO_CGI].revents) {
1165                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1166                         /* Have data from peer and can write to CGI */
1167                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1168                         /* Doesn't happen, we dont use nonblocking IO here
1169                          *if (count < 0 && errno == EAGAIN) {
1170                          *      ...
1171                          *} else */
1172                         if (count > 0) {
1173                                 hdr_ptr += count;
1174                                 hdr_cnt -= count;
1175                         } else {
1176                                 /* EOF/broken pipe to CGI, stop piping POST data */
1177                                 hdr_cnt = post_len = 0;
1178                         }
1179                 }
1180
1181                 if (pfd[0].revents) {
1182                         /* post_len > 0 && hdr_cnt == 0 here */
1183                         /* We expect data, prev data portion is eaten by CGI
1184                          * and there *is* data to read from the peer
1185                          * (POSTDATA) */
1186                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1187                         //count = safe_read(STDIN_FILENO, hdr_buf, count);
1188                         count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1189                         if (count > 0) {
1190                                 hdr_cnt = count;
1191                                 hdr_ptr = hdr_buf;
1192                                 post_len -= count;
1193                         } else {
1194                                 /* no more POST data can be read */
1195                                 post_len = 0;
1196                         }
1197                 }
1198
1199                 if (pfd[FROM_CGI].revents) {
1200                         /* There is something to read from CGI */
1201                         char *rbuf = iobuf;
1202
1203                         /* Are we still buffering CGI output? */
1204                         if (out_cnt >= 0) {
1205                                 /* HTTP_200[] has single "\r\n" at the end.
1206                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1207                                  * CGI scripts MUST send their own header terminated by
1208                                  * empty line, then data. That's why we have only one
1209                                  * <cr><lf> pair here. We will output "200 OK" line
1210                                  * if needed, but CGI still has to provide blank line
1211                                  * between header and body */
1212
1213                                 /* Must use safe_read, not full_read, because
1214                                  * CGI may output a few first bytes and then wait
1215                                  * for POSTDATA without closing stdout.
1216                                  * With full_read we may wait here forever. */
1217                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1218                                 if (count <= 0) {
1219                                         /* eof (or error) and there was no "HTTP",
1220                                          * so write it, then write received data */
1221                                         if (out_cnt) {
1222                                                 full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
1223                                                 full_write(STDOUT_FILENO, rbuf, out_cnt);
1224                                         }
1225                                         break; /* CGI stdout is closed, exiting */
1226                                 }
1227                                 out_cnt += count;
1228                                 count = 0;
1229                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1230                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1231                                         /* send "HTTP/1.0 " */
1232                                         if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
1233                                                 break;
1234                                         rbuf += 8; /* skip "Status: " */
1235                                         count = out_cnt - 8;
1236                                         out_cnt = -1; /* buffering off */
1237                                 } else if (out_cnt >= 4) {
1238                                         /* Did CGI add "HTTP"? */
1239                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1240                                                 /* there is no "HTTP", do it ourself */
1241                                                 if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1242                                                         break;
1243                                         }
1244                                         /* Commented out:
1245                                         if (!strstr(rbuf, "ontent-")) {
1246                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1247                                         }
1248                                          * Counter-example of valid CGI without Content-type:
1249                                          * echo -en "HTTP/1.0 302 Found\r\n"
1250                                          * echo -en "Location: http://www.busybox.net\r\n"
1251                                          * echo -en "\r\n"
1252                                          */
1253                                         count = out_cnt;
1254                                         out_cnt = -1; /* buffering off */
1255                                 }
1256                         } else {
1257                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1258                                 if (count <= 0)
1259                                         break;  /* eof (or error) */
1260                         }
1261                         if (full_write(STDOUT_FILENO, rbuf, count) != count)
1262                                 break;
1263                         if (DEBUG)
1264                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1265                 } /* if (pfd[FROM_CGI].revents) */
1266         } /* while (1) */
1267         log_and_exit();
1268 }
1269 #endif
1270
1271 #if ENABLE_FEATURE_HTTPD_CGI
1272
1273 static void setenv1(const char *name, const char *value)
1274 {
1275         setenv(name, value ? value : "", 1);
1276 }
1277
1278 /*
1279  * Spawn CGI script, forward CGI's stdin/out <=> network
1280  *
1281  * Environment variables are set up and the script is invoked with pipes
1282  * for stdin/stdout.  If a POST is being done the script is fed the POST
1283  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1284  *
1285  * Parameters:
1286  * const char *url              The requested URL (with leading /).
1287  * int post_len                 Length of the POST body.
1288  * const char *cookie           For set HTTP_COOKIE.
1289  * const char *content_type     For set CONTENT_TYPE.
1290  */
1291 static void send_cgi_and_exit(
1292                 const char *url,
1293                 const char *request,
1294                 int post_len,
1295                 const char *cookie,
1296                 const char *content_type) NORETURN;
1297 static void send_cgi_and_exit(
1298                 const char *url,
1299                 const char *request,
1300                 int post_len,
1301                 const char *cookie,
1302                 const char *content_type)
1303 {
1304         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1305         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1306         char *script;
1307         int pid;
1308
1309         /* Make a copy. NB: caller guarantees:
1310          * url[0] == '/', url[1] != '/' */
1311         url = xstrdup(url);
1312
1313         /*
1314          * We are mucking with environment _first_ and then vfork/exec,
1315          * this allows us to use vfork safely. Parent doesn't care about
1316          * these environment changes anyway.
1317          */
1318
1319         /* Check for [dirs/]script.cgi/PATH_INFO */
1320         script = (char*)url;
1321         while ((script = strchr(script + 1, '/')) != NULL) {
1322                 *script = '\0';
1323                 if (!is_directory(url + 1, 1, NULL)) {
1324                         /* not directory, found script.cgi/PATH_INFO */
1325                         *script = '/';
1326                         break;
1327                 }
1328                 *script = '/'; /* is directory, find next '/' */
1329         }
1330         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1331         setenv1("REQUEST_METHOD", request);
1332         if (g_query) {
1333                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1334         } else {
1335                 setenv1("REQUEST_URI", url);
1336         }
1337         if (script != NULL)
1338                 *script = '\0';         /* cut off /PATH_INFO */
1339
1340         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1341         if (home_httpd[0] == '/') {
1342                 char *fullpath = concat_path_file(home_httpd, url);
1343                 setenv1("SCRIPT_FILENAME", fullpath);
1344         }
1345         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1346         setenv1("SCRIPT_NAME", url);
1347         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1348          * QUERY_STRING: The information which follows the ? in the URL
1349          * which referenced this script. This is the query information.
1350          * It should not be decoded in any fashion. This variable
1351          * should always be set when there is query information,
1352          * regardless of command line decoding. */
1353         /* (Older versions of bbox seem to do some decoding) */
1354         setenv1("QUERY_STRING", g_query);
1355         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1356         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1357         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1358         /* Having _separate_ variables for IP and port defeats
1359          * the purpose of having socket abstraction. Which "port"
1360          * are you using on Unix domain socket?
1361          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1362          * Oh well... */
1363         {
1364                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1365                 char *cp = strrchr(p, ':');
1366                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1367                         cp = NULL;
1368                 if (cp) *cp = '\0'; /* delete :PORT */
1369                 setenv1("REMOTE_ADDR", p);
1370                 if (cp) {
1371                         *cp = ':';
1372 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1373                         setenv1("REMOTE_PORT", cp + 1);
1374 #endif
1375                 }
1376         }
1377         setenv1("HTTP_USER_AGENT", user_agent);
1378         if (http_accept)
1379                 setenv1("HTTP_ACCEPT", http_accept);
1380         if (http_accept_language)
1381                 setenv1("HTTP_ACCEPT_LANGUAGE", http_accept_language);
1382         if (post_len)
1383                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1384         if (cookie)
1385                 setenv1("HTTP_COOKIE", cookie);
1386         if (content_type)
1387                 setenv1("CONTENT_TYPE", content_type);
1388 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1389         if (remoteuser) {
1390                 setenv1("REMOTE_USER", remoteuser);
1391                 putenv((char*)"AUTH_TYPE=Basic");
1392         }
1393 #endif
1394         if (referer)
1395                 setenv1("HTTP_REFERER", referer);
1396         setenv1("HTTP_HOST", host); /* set to "" if NULL */
1397         /* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
1398          * just run "env SERVER_NAME=xyz httpd ..." instead */
1399
1400         xpiped_pair(fromCgi);
1401         xpiped_pair(toCgi);
1402
1403         pid = vfork();
1404         if (pid < 0) {
1405                 /* TODO: log perror? */
1406                 log_and_exit();
1407         }
1408
1409         if (!pid) {
1410                 /* Child process */
1411                 char *argv[3];
1412
1413                 xfunc_error_retval = 242;
1414
1415                 /* NB: close _first_, then move fds! */
1416                 close(toCgi.wr);
1417                 close(fromCgi.rd);
1418                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1419                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1420                 /* User seeing stderr output can be a security problem.
1421                  * If CGI really wants that, it can always do dup itself. */
1422                 /* dup2(1, 2); */
1423
1424                 /* Chdiring to script's dir */
1425                 script = strrchr(url, '/');
1426                 if (script != url) { /* paranoia */
1427                         *script = '\0';
1428                         if (chdir(url + 1) != 0) {
1429                                 bb_perror_msg("chdir(%s)", url + 1);
1430                                 goto error_execing_cgi;
1431                         }
1432                         // not needed: *script = '/';
1433                 }
1434                 script++;
1435
1436                 /* set argv[0] to name without path */
1437                 argv[0] = script;
1438                 argv[1] = NULL;
1439
1440 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1441                 {
1442                         char *suffix = strrchr(script, '.');
1443
1444                         if (suffix) {
1445                                 Htaccess *cur;
1446                                 for (cur = script_i; cur; cur = cur->next) {
1447                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1448                                                 /* found interpreter name */
1449                                                 argv[0] = cur->after_colon;
1450                                                 argv[1] = script;
1451                                                 argv[2] = NULL;
1452                                                 break;
1453                                         }
1454                                 }
1455                         }
1456                 }
1457 #endif
1458                 /* restore default signal dispositions for CGI process */
1459                 bb_signals(0
1460                         | (1 << SIGCHLD)
1461                         | (1 << SIGPIPE)
1462                         | (1 << SIGHUP)
1463                         , SIG_DFL);
1464
1465                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1466                  * without any dir components and will only match a file
1467                  * in the current directory */
1468                 execv(argv[0], argv);
1469                 if (verbose)
1470                         bb_perror_msg("can't execute '%s'", argv[0]);
1471  error_execing_cgi:
1472                 /* send to stdout
1473                  * (we are CGI here, our stdout is pumped to the net) */
1474                 send_headers_and_exit(HTTP_NOT_FOUND);
1475         } /* end child */
1476
1477         /* Parent process */
1478
1479         /* Restore variables possibly changed by child */
1480         xfunc_error_retval = 0;
1481
1482         /* Pump data */
1483         close(fromCgi.wr);
1484         close(toCgi.rd);
1485         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1486 }
1487
1488 #endif          /* FEATURE_HTTPD_CGI */
1489
1490 /*
1491  * Send a file response to a HTTP request, and exit
1492  *
1493  * Parameters:
1494  * const char *url  The requested URL (with leading /).
1495  * what             What to send (headers/body/both).
1496  */
1497 static NOINLINE void send_file_and_exit(const char *url, int what)
1498 {
1499         char *suffix;
1500         int fd;
1501         ssize_t count;
1502
1503         fd = open(url, O_RDONLY);
1504         if (fd < 0) {
1505                 if (DEBUG)
1506                         bb_perror_msg("can't open '%s'", url);
1507                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1508                  * IOW: it is unsafe to call send_headers_and_exit
1509                  * if what is SEND_BODY! Can recurse! */
1510                 if (what != SEND_BODY)
1511                         send_headers_and_exit(HTTP_NOT_FOUND);
1512                 log_and_exit();
1513         }
1514         /* If you want to know about EPIPE below
1515          * (happens if you abort downloads from local httpd): */
1516         signal(SIGPIPE, SIG_IGN);
1517
1518         /* If not found, default is "application/octet-stream" */
1519         found_mime_type = "application/octet-stream";
1520         suffix = strrchr(url, '.');
1521         if (suffix) {
1522                 static const char suffixTable[] ALIGN1 =
1523                         /* Shorter suffix must be first:
1524                          * ".html.htm" will fail for ".htm"
1525                          */
1526                         ".txt.h.c.cc.cpp\0" "text/plain\0"
1527                         /* .htm line must be after .h line */
1528                         ".htm.html\0" "text/html\0"
1529                         ".jpg.jpeg\0" "image/jpeg\0"
1530                         ".gif\0"      "image/gif\0"
1531                         ".png\0"      "image/png\0"
1532                         /* .css line must be after .c line */
1533                         ".css\0"      "text/css\0"
1534                         ".wav\0"      "audio/wav\0"
1535                         ".avi\0"      "video/x-msvideo\0"
1536                         ".qt.mov\0"   "video/quicktime\0"
1537                         ".mpe.mpeg\0" "video/mpeg\0"
1538                         ".mid.midi\0" "audio/midi\0"
1539                         ".mp3\0"      "audio/mpeg\0"
1540 #if 0  /* unpopular */
1541                         ".au\0"       "audio/basic\0"
1542                         ".pac\0"      "application/x-ns-proxy-autoconfig\0"
1543                         ".vrml.wrl\0" "model/vrml\0"
1544 #endif
1545                         /* compiler adds another "\0" here */
1546                 ;
1547                 Htaccess *cur;
1548
1549                 /* Examine built-in table */
1550                 const char *table = suffixTable;
1551                 const char *table_next;
1552                 for (; *table; table = table_next) {
1553                         const char *try_suffix;
1554                         const char *mime_type;
1555                         mime_type  = table + strlen(table) + 1;
1556                         table_next = mime_type + strlen(mime_type) + 1;
1557                         try_suffix = strstr(table, suffix);
1558                         if (!try_suffix)
1559                                 continue;
1560                         try_suffix += strlen(suffix);
1561                         if (*try_suffix == '\0' || *try_suffix == '.') {
1562                                 found_mime_type = mime_type;
1563                                 break;
1564                         }
1565                         /* Example: strstr(table, ".av") != NULL, but it
1566                          * does not match ".avi" after all and we end up here.
1567                          * The table is arranged so that in this case we know
1568                          * that it can't match anything in the following lines,
1569                          * and we stop the search: */
1570                         break;
1571                 }
1572                 /* ...then user's table */
1573                 for (cur = mime_a; cur; cur = cur->next) {
1574                         if (strcmp(cur->before_colon, suffix) == 0) {
1575                                 found_mime_type = cur->after_colon;
1576                                 break;
1577                         }
1578                 }
1579         }
1580
1581         if (DEBUG)
1582                 bb_error_msg("sending file '%s' content-type: %s",
1583                         url, found_mime_type);
1584
1585 #if ENABLE_FEATURE_HTTPD_RANGES
1586         if (what == SEND_BODY)
1587                 range_start = 0; /* err pages and ranges don't mix */
1588         range_len = MAXINT(off_t);
1589         if (range_start) {
1590                 if (!range_end) {
1591                         range_end = file_size - 1;
1592                 }
1593                 if (range_end < range_start
1594                  || lseek(fd, range_start, SEEK_SET) != range_start
1595                 ) {
1596                         lseek(fd, 0, SEEK_SET);
1597                         range_start = 0;
1598                 } else {
1599                         range_len = range_end - range_start + 1;
1600                         send_headers(HTTP_PARTIAL_CONTENT);
1601                         what = SEND_BODY;
1602                 }
1603         }
1604 #endif
1605         if (what & SEND_HEADERS)
1606                 send_headers(HTTP_OK);
1607 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1608         {
1609                 off_t offset = range_start;
1610                 while (1) {
1611                         /* sz is rounded down to 64k */
1612                         ssize_t sz = MAXINT(ssize_t) - 0xffff;
1613                         IF_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1614                         count = sendfile(STDOUT_FILENO, fd, &offset, sz);
1615                         if (count < 0) {
1616                                 if (offset == range_start)
1617                                         break; /* fall back to read/write loop */
1618                                 goto fin;
1619                         }
1620                         IF_FEATURE_HTTPD_RANGES(range_len -= sz;)
1621                         if (count == 0 || range_len == 0)
1622                                 log_and_exit();
1623                 }
1624         }
1625 #endif
1626         while ((count = safe_read(fd, iobuf, IOBUF_SIZE)) > 0) {
1627                 ssize_t n;
1628                 IF_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1629                 n = full_write(STDOUT_FILENO, iobuf, count);
1630                 if (count != n)
1631                         break;
1632                 IF_FEATURE_HTTPD_RANGES(range_len -= count;)
1633                 if (range_len == 0)
1634                         break;
1635         }
1636         if (count < 0) {
1637  IF_FEATURE_HTTPD_USE_SENDFILE(fin:)
1638                 if (verbose > 1)
1639                         bb_perror_msg("error");
1640         }
1641         log_and_exit();
1642 }
1643
1644 static int checkPermIP(void)
1645 {
1646         Htaccess_IP *cur;
1647
1648         for (cur = ip_a_d; cur; cur = cur->next) {
1649 #if DEBUG
1650                 fprintf(stderr,
1651                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1652                         rmt_ip_str,
1653                         (unsigned char)(cur->ip >> 24),
1654                         (unsigned char)(cur->ip >> 16),
1655                         (unsigned char)(cur->ip >> 8),
1656                         (unsigned char)(cur->ip),
1657                         (unsigned char)(cur->mask >> 24),
1658                         (unsigned char)(cur->mask >> 16),
1659                         (unsigned char)(cur->mask >> 8),
1660                         (unsigned char)(cur->mask)
1661                 );
1662 #endif
1663                 if ((rmt_ip & cur->mask) == cur->ip)
1664                         return (cur->allow_deny == 'A'); /* A -> 1 */
1665         }
1666
1667         return !flg_deny_all; /* depends on whether we saw "D:*" */
1668 }
1669
1670 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1671 /*
1672  * Config file entries are of the form "/<path>:<user>:<passwd>".
1673  * If config file has no prefix match for path, access is allowed.
1674  *
1675  * path                 The file path
1676  * user_and_passwd      "user:passwd" to validate
1677  *
1678  * Returns 1 if user_and_passwd is OK.
1679  */
1680 static int check_user_passwd(const char *path, const char *user_and_passwd)
1681 {
1682         Htaccess *cur;
1683         const char *prev = NULL;
1684
1685         for (cur = g_auth; cur; cur = cur->next) {
1686                 const char *dir_prefix;
1687                 size_t len;
1688
1689                 dir_prefix = cur->before_colon;
1690
1691                 /* WHY? */
1692                 /* If already saw a match, don't accept other different matches */
1693                 if (prev && strcmp(prev, dir_prefix) != 0)
1694                         continue;
1695
1696                 if (DEBUG)
1697                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
1698
1699                 /* If it's not a prefix match, continue searching */
1700                 len = strlen(dir_prefix);
1701                 if (len != 1 /* dir_prefix "/" matches all, don't need to check */
1702                  && (strncmp(dir_prefix, path, len) != 0
1703                     || (path[len] != '/' && path[len] != '\0'))
1704                 ) {
1705                         continue;
1706                 }
1707
1708                 /* Path match found */
1709                 prev = dir_prefix;
1710
1711                 if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1712                         char *md5_passwd;
1713
1714                         md5_passwd = strchr(cur->after_colon, ':');
1715                         if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
1716                          && md5_passwd[3] == '$' && md5_passwd[4]
1717                         ) {
1718                                 char *encrypted;
1719                                 int r, user_len_p1;
1720
1721                                 md5_passwd++;
1722                                 user_len_p1 = md5_passwd - cur->after_colon;
1723                                 /* comparing "user:" */
1724                                 if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
1725                                         continue;
1726                                 }
1727
1728                                 encrypted = pw_encrypt(
1729                                         user_and_passwd + user_len_p1 /* cleartext pwd from user */,
1730                                         md5_passwd /*salt */, 1 /* cleanup */);
1731                                 r = strcmp(encrypted, md5_passwd);
1732                                 free(encrypted);
1733                                 if (r == 0)
1734                                         goto set_remoteuser_var; /* Ok */
1735                                 continue;
1736                         }
1737                 }
1738
1739                 /* Comparing plaintext "user:pass" in one go */
1740                 if (strcmp(cur->after_colon, user_and_passwd) == 0) {
1741  set_remoteuser_var:
1742                         remoteuser = xstrndup(user_and_passwd,
1743                                         strchrnul(user_and_passwd, ':') - user_and_passwd);
1744                         return 1; /* Ok */
1745                 }
1746         } /* for */
1747
1748         /* 0(bad) if prev is set: matches were found but passwd was wrong */
1749         return (prev == NULL);
1750 }
1751 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1752
1753 #if ENABLE_FEATURE_HTTPD_PROXY
1754 static Htaccess_Proxy *find_proxy_entry(const char *url)
1755 {
1756         Htaccess_Proxy *p;
1757         for (p = proxy; p; p = p->next) {
1758                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1759                         return p;
1760         }
1761         return NULL;
1762 }
1763 #endif
1764
1765 /*
1766  * Handle timeouts
1767  */
1768 static void send_REQUEST_TIMEOUT_and_exit(int sig) NORETURN;
1769 static void send_REQUEST_TIMEOUT_and_exit(int sig UNUSED_PARAM)
1770 {
1771         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1772 }
1773
1774 /*
1775  * Handle an incoming http request and exit.
1776  */
1777 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
1778 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1779 {
1780         static const char request_GET[] ALIGN1 = "GET";
1781         struct stat sb;
1782         char *urlcopy;
1783         char *urlp;
1784         char *tptr;
1785 #if ENABLE_FEATURE_HTTPD_CGI
1786         static const char request_HEAD[] ALIGN1 = "HEAD";
1787         const char *prequest;
1788         char *cookie = NULL;
1789         char *content_type = NULL;
1790         unsigned long length = 0;
1791 #elif ENABLE_FEATURE_HTTPD_PROXY
1792 #define prequest request_GET
1793         unsigned long length = 0;
1794 #endif
1795 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1796         smallint authorized = -1;
1797 #endif
1798         smallint ip_allowed;
1799         char http_major_version;
1800 #if ENABLE_FEATURE_HTTPD_PROXY
1801         char http_minor_version;
1802         char *header_buf = header_buf; /* for gcc */
1803         char *header_ptr = header_ptr;
1804         Htaccess_Proxy *proxy_entry;
1805 #endif
1806
1807         /* Allocation of iobuf is postponed until now
1808          * (IOW, server process doesn't need to waste 8k) */
1809         iobuf = xmalloc(IOBUF_SIZE);
1810
1811         rmt_ip = 0;
1812         if (fromAddr->u.sa.sa_family == AF_INET) {
1813                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1814         }
1815 #if ENABLE_FEATURE_IPV6
1816         if (fromAddr->u.sa.sa_family == AF_INET6
1817          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1818          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1819          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1820                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1821 #endif
1822         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1823                 /* NB: can be NULL (user runs httpd -i by hand?) */
1824                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1825         }
1826         if (verbose) {
1827                 /* this trick makes -v logging much simpler */
1828                 if (rmt_ip_str)
1829                         applet_name = rmt_ip_str;
1830                 if (verbose > 2)
1831                         bb_error_msg("connected");
1832         }
1833
1834         /* Install timeout handler. get_line() needs it. */
1835         signal(SIGALRM, send_REQUEST_TIMEOUT_and_exit);
1836
1837         if (!get_line()) /* EOF or error or empty line */
1838                 send_headers_and_exit(HTTP_BAD_REQUEST);
1839
1840         /* Determine type of request (GET/POST) */
1841         urlp = strpbrk(iobuf, " \t");
1842         if (urlp == NULL)
1843                 send_headers_and_exit(HTTP_BAD_REQUEST);
1844         *urlp++ = '\0';
1845 #if ENABLE_FEATURE_HTTPD_CGI
1846         prequest = request_GET;
1847         if (strcasecmp(iobuf, prequest) != 0) {
1848                 prequest = request_HEAD;
1849                 if (strcasecmp(iobuf, prequest) != 0) {
1850                         prequest = "POST";
1851                         if (strcasecmp(iobuf, prequest) != 0)
1852                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1853                 }
1854         }
1855 #else
1856         if (strcasecmp(iobuf, request_GET) != 0)
1857                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1858 #endif
1859         urlp = skip_whitespace(urlp);
1860         if (urlp[0] != '/')
1861                 send_headers_and_exit(HTTP_BAD_REQUEST);
1862
1863         /* Find end of URL and parse HTTP version, if any */
1864         http_major_version = '0';
1865         IF_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1866         tptr = strchrnul(urlp, ' ');
1867         /* Is it " HTTP/"? */
1868         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1869                 http_major_version = tptr[6];
1870                 IF_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1871         }
1872         *tptr = '\0';
1873
1874         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1875         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1876         /*if (urlcopy == NULL)
1877          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1878         strcpy(urlcopy, urlp);
1879         /* NB: urlcopy ptr is never changed after this */
1880
1881         /* Extract url args if present */
1882         g_query = NULL;
1883         tptr = strchr(urlcopy, '?');
1884         if (tptr) {
1885                 *tptr++ = '\0';
1886                 g_query = tptr;
1887         }
1888
1889         /* Decode URL escape sequences */
1890         tptr = decodeString(urlcopy, 0);
1891         if (tptr == NULL)
1892                 send_headers_and_exit(HTTP_BAD_REQUEST);
1893         if (tptr == urlcopy + 1) {
1894                 /* '/' or NUL is encoded */
1895                 send_headers_and_exit(HTTP_NOT_FOUND);
1896         }
1897
1898         /* Canonicalize path */
1899         /* Algorithm stolen from libbb bb_simplify_path(),
1900          * but don't strdup, retain trailing slash, protect root */
1901         urlp = tptr = urlcopy;
1902         do {
1903                 if (*urlp == '/') {
1904                         /* skip duplicate (or initial) slash */
1905                         if (*tptr == '/') {
1906                                 continue;
1907                         }
1908                         if (*tptr == '.') {
1909                                 /* skip extra "/./" */
1910                                 if (tptr[1] == '/' || !tptr[1]) {
1911                                         continue;
1912                                 }
1913                                 /* "..": be careful */
1914                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1915                                         ++tptr;
1916                                         if (urlp == urlcopy) /* protect root */
1917                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1918                                         while (*--urlp != '/') /* omit previous dir */;
1919                                                 continue;
1920                                 }
1921                         }
1922                 }
1923                 *++urlp = *tptr;
1924         } while (*++tptr);
1925         *++urlp = '\0';       /* terminate after last character */
1926
1927         /* If URL is a directory, add '/' */
1928         if (urlp[-1] != '/') {
1929                 if (is_directory(urlcopy + 1, 1, NULL)) {
1930                         found_moved_temporarily = urlcopy;
1931                 }
1932         }
1933
1934         /* Log it */
1935         if (verbose > 1)
1936                 bb_error_msg("url:%s", urlcopy);
1937
1938         tptr = urlcopy;
1939         ip_allowed = checkPermIP();
1940         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1941                 /* have path1/path2 */
1942                 *tptr = '\0';
1943                 if (is_directory(urlcopy + 1, 1, NULL)) {
1944                         /* may have subdir config */
1945                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1946                         ip_allowed = checkPermIP();
1947                 }
1948                 *tptr = '/';
1949         }
1950
1951 #if ENABLE_FEATURE_HTTPD_PROXY
1952         proxy_entry = find_proxy_entry(urlcopy);
1953         if (proxy_entry)
1954                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1955 #endif
1956
1957         if (http_major_version >= '0') {
1958                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1959
1960                 /* Read until blank line */
1961                 while (1) {
1962                         if (!get_line())
1963                                 break; /* EOF or error or empty line */
1964                         if (DEBUG)
1965                                 bb_error_msg("header: '%s'", iobuf);
1966
1967 #if ENABLE_FEATURE_HTTPD_PROXY
1968                         /* We need 2 more bytes for yet another "\r\n" -
1969                          * see near fdprintf(proxy_fd...) further below */
1970                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1971                                 int len = strlen(iobuf);
1972                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1973                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1974                                 memcpy(header_ptr, iobuf, len);
1975                                 header_ptr += len;
1976                                 header_ptr[0] = '\r';
1977                                 header_ptr[1] = '\n';
1978                                 header_ptr += 2;
1979                         }
1980 #endif
1981
1982 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1983                         /* Try and do our best to parse more lines */
1984                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1985                                 /* extra read only for POST */
1986                                 if (prequest != request_GET
1987 # if ENABLE_FEATURE_HTTPD_CGI
1988                                  && prequest != request_HEAD
1989 # endif
1990                                 ) {
1991                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1992                                         if (!tptr[0])
1993                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1994                                         /* not using strtoul: it ignores leading minus! */
1995                                         length = bb_strtou(tptr, NULL, 10);
1996                                         /* length is "ulong", but we need to pass it to int later */
1997                                         if (errno || length > INT_MAX)
1998                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1999                                 }
2000                         }
2001 #endif
2002 #if ENABLE_FEATURE_HTTPD_CGI
2003                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
2004                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
2005                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
2006                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
2007                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
2008                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
2009                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2010                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2011                         } else if (STRNCASECMP(iobuf, "Host:") == 0) {
2012                                 host = xstrdup(skip_whitespace(iobuf + sizeof("Host:")-1));
2013                         } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
2014                                 http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
2015                         } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
2016                                 http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
2017                         }
2018 #endif
2019 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2020                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2021                                 /* We only allow Basic credentials.
2022                                  * It shows up as "Authorization: Basic <user>:<passwd>" where
2023                                  * "<user>:<passwd>" is base64 encoded.
2024                                  */
2025                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2026                                 if (STRNCASECMP(tptr, "Basic") != 0)
2027                                         continue;
2028                                 tptr += sizeof("Basic")-1;
2029                                 /* decodeBase64() skips whitespace itself */
2030                                 decodeBase64(tptr);
2031                                 authorized = check_user_passwd(urlcopy, tptr);
2032                         }
2033 #endif
2034 #if ENABLE_FEATURE_HTTPD_RANGES
2035                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2036                                 /* We know only bytes=NNN-[MMM] */
2037                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2038                                 if (strncmp(s, "bytes=", 6) == 0) {
2039                                         s += sizeof("bytes=")-1;
2040                                         range_start = BB_STRTOOFF(s, &s, 10);
2041                                         if (s[0] != '-' || range_start < 0) {
2042                                                 range_start = 0;
2043                                         } else if (s[1]) {
2044                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2045                                                 if (errno || range_end < range_start)
2046                                                         range_start = 0;
2047                                         }
2048                                 }
2049                         }
2050 #endif
2051                 } /* while extra header reading */
2052         }
2053
2054         /* We are done reading headers, disable peer timeout */
2055         alarm(0);
2056
2057         if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0 || !ip_allowed) {
2058                 /* protect listing [/path]/httpd.conf or IP deny */
2059                 send_headers_and_exit(HTTP_FORBIDDEN);
2060         }
2061
2062 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2063         /* Case: no "Authorization:" was seen, but page does require passwd.
2064          * Check that with dummy user:pass */
2065         if (authorized < 0)
2066                 authorized = check_user_passwd(urlcopy, ":");
2067         if (!authorized)
2068                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2069 #endif
2070
2071         if (found_moved_temporarily) {
2072                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2073         }
2074
2075 #if ENABLE_FEATURE_HTTPD_PROXY
2076         if (proxy_entry != NULL) {
2077                 int proxy_fd;
2078                 len_and_sockaddr *lsa;
2079
2080                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2081                 if (proxy_fd < 0)
2082                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2083                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2084                 if (lsa == NULL)
2085                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2086                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2087                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2088                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2089                                 prequest, /* GET or POST */
2090                                 proxy_entry->url_to, /* url part 1 */
2091                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2092                                 (g_query ? "?" : ""), /* "?" (maybe) */
2093                                 (g_query ? g_query : ""), /* query string (maybe) */
2094                                 http_major_version, http_minor_version);
2095                 header_ptr[0] = '\r';
2096                 header_ptr[1] = '\n';
2097                 header_ptr += 2;
2098                 write(proxy_fd, header_buf, header_ptr - header_buf);
2099                 free(header_buf); /* on the order of 8k, free it */
2100                 cgi_io_loop_and_exit(proxy_fd, proxy_fd, length);
2101         }
2102 #endif
2103
2104         tptr = urlcopy + 1;      /* skip first '/' */
2105
2106 #if ENABLE_FEATURE_HTTPD_CGI
2107         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2108                 if (tptr[8] == '\0') {
2109                         /* protect listing "cgi-bin/" */
2110                         send_headers_and_exit(HTTP_FORBIDDEN);
2111                 }
2112                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2113         }
2114 #endif
2115
2116         if (urlp[-1] == '/')
2117                 strcpy(urlp, index_page);
2118         if (stat(tptr, &sb) == 0) {
2119 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2120                 char *suffix = strrchr(tptr, '.');
2121                 if (suffix) {
2122                         Htaccess *cur;
2123                         for (cur = script_i; cur; cur = cur->next) {
2124                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2125                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2126                                 }
2127                         }
2128                 }
2129 #endif
2130                 file_size = sb.st_size;
2131                 last_mod = sb.st_mtime;
2132         }
2133 #if ENABLE_FEATURE_HTTPD_CGI
2134         else if (urlp[-1] == '/') {
2135                 /* It's a dir URL and there is no index.html
2136                  * Try cgi-bin/index.cgi */
2137                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2138                         urlp[0] = '\0';
2139                         g_query = urlcopy;
2140                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2141                 }
2142         }
2143         /* else fall through to send_file, it errors out if open fails: */
2144
2145         if (prequest != request_GET && prequest != request_HEAD) {
2146                 /* POST for files does not make sense */
2147                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2148         }
2149         send_file_and_exit(tptr,
2150                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2151         );
2152 #else
2153         send_file_and_exit(tptr, SEND_HEADERS_AND_BODY);
2154 #endif
2155 }
2156
2157 /*
2158  * The main http server function.
2159  * Given a socket, listen for new connections and farm out
2160  * the processing as a [v]forked process.
2161  * Never returns.
2162  */
2163 #if BB_MMU
2164 static void mini_httpd(int server_socket) NORETURN;
2165 static void mini_httpd(int server_socket)
2166 {
2167         /* NB: it's best to not use xfuncs in this loop before fork().
2168          * Otherwise server may die on transient errors (temporary
2169          * out-of-memory condition, etc), which is Bad(tm).
2170          * Try to do any dangerous calls after fork.
2171          */
2172         while (1) {
2173                 int n;
2174                 len_and_sockaddr fromAddr;
2175
2176                 /* Wait for connections... */
2177                 fromAddr.len = LSA_SIZEOF_SA;
2178                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2179                 if (n < 0)
2180                         continue;
2181
2182                 /* set the KEEPALIVE option to cull dead connections */
2183                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2184
2185                 if (fork() == 0) {
2186                         /* child */
2187                         /* Do not reload config on HUP */
2188                         signal(SIGHUP, SIG_IGN);
2189                         close(server_socket);
2190                         xmove_fd(n, 0);
2191                         xdup2(0, 1);
2192
2193                         handle_incoming_and_exit(&fromAddr);
2194                 }
2195                 /* parent, or fork failed */
2196                 close(n);
2197         } /* while (1) */
2198         /* never reached */
2199 }
2200 #else
2201 static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
2202 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2203 {
2204         char *argv_copy[argc + 2];
2205
2206         argv_copy[0] = argv[0];
2207         argv_copy[1] = (char*)"-i";
2208         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2209
2210         /* NB: it's best to not use xfuncs in this loop before vfork().
2211          * Otherwise server may die on transient errors (temporary
2212          * out-of-memory condition, etc), which is Bad(tm).
2213          * Try to do any dangerous calls after fork.
2214          */
2215         while (1) {
2216                 int n;
2217                 len_and_sockaddr fromAddr;
2218
2219                 /* Wait for connections... */
2220                 fromAddr.len = LSA_SIZEOF_SA;
2221                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2222                 if (n < 0)
2223                         continue;
2224
2225                 /* set the KEEPALIVE option to cull dead connections */
2226                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2227
2228                 if (vfork() == 0) {
2229                         /* child */
2230                         /* Do not reload config on HUP */
2231                         signal(SIGHUP, SIG_IGN);
2232                         close(server_socket);
2233                         xmove_fd(n, 0);
2234                         xdup2(0, 1);
2235
2236                         /* Run a copy of ourself in inetd mode */
2237                         re_exec(argv_copy);
2238                 }
2239                 /* parent, or vfork failed */
2240                 close(n);
2241         } /* while (1) */
2242         /* never reached */
2243 }
2244 #endif
2245
2246 /*
2247  * Process a HTTP connection on stdin/out.
2248  * Never returns.
2249  */
2250 static void mini_httpd_inetd(void) NORETURN;
2251 static void mini_httpd_inetd(void)
2252 {
2253         len_and_sockaddr fromAddr;
2254
2255         memset(&fromAddr, 0, sizeof(fromAddr));
2256         fromAddr.len = LSA_SIZEOF_SA;
2257         /* NB: can fail if user runs it by hand and types in http cmds */
2258         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2259         handle_incoming_and_exit(&fromAddr);
2260 }
2261
2262 static void sighup_handler(int sig UNUSED_PARAM)
2263 {
2264         parse_conf(DEFAULT_PATH_HTTPD_CONF, SIGNALED_PARSE);
2265 }
2266
2267 enum {
2268         c_opt_config_file = 0,
2269         d_opt_decode_url,
2270         h_opt_home_httpd,
2271         IF_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2272         IF_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2273         IF_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2274         IF_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2275         p_opt_port      ,
2276         p_opt_inetd     ,
2277         p_opt_foreground,
2278         p_opt_verbose   ,
2279         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2280         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2281         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2282         OPT_ENCODE_URL  = IF_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2283         OPT_REALM       = IF_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2284         OPT_MD5         = IF_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2285         OPT_SETUID      = IF_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2286         OPT_PORT        = 1 << p_opt_port,
2287         OPT_INETD       = 1 << p_opt_inetd,
2288         OPT_FOREGROUND  = 1 << p_opt_foreground,
2289         OPT_VERBOSE     = 1 << p_opt_verbose,
2290 };
2291
2292
2293 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2294 int httpd_main(int argc UNUSED_PARAM, char **argv)
2295 {
2296         int server_socket = server_socket; /* for gcc */
2297         unsigned opt;
2298         char *url_for_decode;
2299         IF_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2300         IF_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2301         IF_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2302         IF_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2303
2304         INIT_G();
2305
2306 #if ENABLE_LOCALE_SUPPORT
2307         /* Undo busybox.c: we want to speak English in http (dates etc) */
2308         setlocale(LC_TIME, "C");
2309 #endif
2310
2311         home_httpd = xrealloc_getcwd_or_warn(NULL);
2312         /* -v counts, -i implies -f */
2313         opt_complementary = "vv:if";
2314         /* We do not "absolutize" path given by -h (home) opt.
2315          * If user gives relative path in -h,
2316          * $SCRIPT_FILENAME will not be set. */
2317         opt = getopt32(argv, "c:d:h:"
2318                         IF_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2319                         IF_FEATURE_HTTPD_BASIC_AUTH("r:")
2320                         IF_FEATURE_HTTPD_AUTH_MD5("m:")
2321                         IF_FEATURE_HTTPD_SETUID("u:")
2322                         "p:ifv",
2323                         &opt_c_configFile, &url_for_decode, &home_httpd
2324                         IF_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2325                         IF_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2326                         IF_FEATURE_HTTPD_AUTH_MD5(, &pass)
2327                         IF_FEATURE_HTTPD_SETUID(, &s_ugid)
2328                         , &bind_addr_or_port
2329                         , &verbose
2330                 );
2331         if (opt & OPT_DECODE_URL) {
2332                 fputs(decodeString(url_for_decode, 1), stdout);
2333                 return 0;
2334         }
2335 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2336         if (opt & OPT_ENCODE_URL) {
2337                 fputs(encodeString(url_for_encode), stdout);
2338                 return 0;
2339         }
2340 #endif
2341 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2342         if (opt & OPT_MD5) {
2343                 char salt[sizeof("$1$XXXXXXXX")];
2344                 salt[0] = '$';
2345                 salt[1] = '1';
2346                 salt[2] = '$';
2347                 crypt_make_salt(salt + 3, 4, 0);
2348                 puts(pw_encrypt(pass, salt, 1));
2349                 return 0;
2350         }
2351 #endif
2352 #if ENABLE_FEATURE_HTTPD_SETUID
2353         if (opt & OPT_SETUID) {
2354                 xget_uidgid(&ugid, s_ugid);
2355         }
2356 #endif
2357
2358 #if !BB_MMU
2359         if (!(opt & OPT_FOREGROUND)) {
2360                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2361         }
2362 #endif
2363
2364         xchdir(home_httpd);
2365         if (!(opt & OPT_INETD)) {
2366                 signal(SIGCHLD, SIG_IGN);
2367                 server_socket = openServer();
2368 #if ENABLE_FEATURE_HTTPD_SETUID
2369                 /* drop privileges */
2370                 if (opt & OPT_SETUID) {
2371                         if (ugid.gid != (gid_t)-1) {
2372                                 if (setgroups(1, &ugid.gid) == -1)
2373                                         bb_perror_msg_and_die("setgroups");
2374                                 xsetgid(ugid.gid);
2375                         }
2376                         xsetuid(ugid.uid);
2377                 }
2378 #endif
2379         }
2380
2381 #if 0
2382         /* User can do it himself: 'env - PATH="$PATH" httpd'
2383          * We don't do it because we don't want to screw users
2384          * which want to do
2385          * 'env - VAR1=val1 VAR2=val2 httpd'
2386          * and have VAR1 and VAR2 values visible in their CGIs.
2387          * Besides, it is also smaller. */
2388         {
2389                 char *p = getenv("PATH");
2390                 /* env strings themself are not freed, no need to xstrdup(p): */
2391                 clearenv();
2392                 if (p)
2393                         putenv(p - 5);
2394 //              if (!(opt & OPT_INETD))
2395 //                      setenv_long("SERVER_PORT", ???);
2396         }
2397 #endif
2398
2399         parse_conf(DEFAULT_PATH_HTTPD_CONF, FIRST_PARSE);
2400         if (!(opt & OPT_INETD))
2401                 signal(SIGHUP, sighup_handler);
2402
2403         xfunc_error_retval = 0;
2404         if (opt & OPT_INETD)
2405                 mini_httpd_inetd();
2406 #if BB_MMU
2407         if (!(opt & OPT_FOREGROUND))
2408                 bb_daemonize(0); /* don't change current directory */
2409         mini_httpd(server_socket); /* never returns */
2410 #else
2411         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2412 #endif
2413         /* return 0; */
2414 }