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  * simplify patch stolen from libbb without using strdup
   9  *
  10  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  11  *
  12  *****************************************************************************
  13  *
  14  * Typical usage:
  15  *   for non root user
  16  * httpd -p 8080 -h $HOME/public_html
  17  *   or for daemon start from rc script with uid=0:
  18  * httpd -u www
  19  * This is equivalent if www user have uid=80 to
  20  * httpd -p 80 -u 80 -h /www -c /etc/httpd.conf -r "Web Server Authentication"
  21  *
  22  *
  23  * When a url starts by "/cgi-bin/" it is assumed to be a cgi script.  The
  24  * server changes directory to the location of the script and executes it
  25  * after setting QUERY_STRING and other environment variables.
  26  *
  27  * Doc:
  28  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
  29  *
  30  * The applet can also be invoked as a url arg decoder and html text encoder
  31  * as follows:
  32  *  foo=`httpd -d $foo`           # decode "Hello%20World" as "Hello World"
  33  *  bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
  34  * Note that url encoding for arguments is not the same as html encoding for
  35  * presentation.  -d decodes a url-encoded argument while -e encodes in html
  36  * for page display.
  37  *
  38  * httpd.conf has the following format:
  39  *
  40  * H:/serverroot     # define the server root. It will override -h
  41  * A:172.20.         # Allow address from 172.20.0.0/16
  42  * A:10.0.0.0/25     # Allow any address from 10.0.0.0-10.0.0.127
  43  * A:10.0.0.0/255.255.255.128  # Allow any address that previous set
  44  * A:127.0.0.1       # Allow local loopback connections
  45  * D:*               # Deny from other IP connections
  46  * E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
  47  * I:index.html      # Show index.html when a directory is requested
  48  *
  49  * P:/url:[http://]hostname[:port]/new/path
  50  *                   # When /urlXXXXXX is requested, reverse proxy
  51  *                   # it to http://hostname[:port]/new/pathXXXXXX
  52  *
  53  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
  54  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
  55  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
  56  * .au:audio/basic   # additional mime type for audio.au files
  57  * *.php:/path/php   # running cgi.php scripts through an interpreter
  58  *
  59  * A/D may be as a/d or allow/deny - only first char matters.
  60  * Deny/Allow IP logic:
  61  *  - Default is to allow all (Allow all (A:*) is a no-op).
  62  *  - Deny rules take precedence over allow rules.
  63  *  - "Deny all" rule (D:*) is applied last.
  64  *
  65  * Example:
  66  *   1. Allow only specified addresses
  67  *     A:172.20          # Allow any address that begins with 172.20.
  68  *     A:10.10.          # Allow any address that begins with 10.10.
  69  *     A:127.0.0.1       # Allow local loopback connections
  70  *     D:*               # Deny from other IP connections
  71  *
  72  *   2. Only deny specified addresses
  73  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
  74  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
  75  *     A:*             # (optional line added for clarity)
  76  *
  77  * If a sub directory contains a config file it is parsed and merged with
  78  * any existing settings as if it was appended to the original configuration.
  79  *
  80  * subdir paths are relative to the containing subdir and thus cannot
  81  * affect the parent rules.
  82  *
  83  * Note that since the sub dir is parsed in the forked thread servicing the
  84  * subdir http request, any merge is discarded when the process exits.  As a
  85  * result, the subdir settings only have a lifetime of a single request.
  86  *
  87  * Custom error pages can contain an absolute path or be relative to
  88  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
  89  * page can only be defined in the root configuration file and are not taken
  90  * into account in local (directories) config files.
  91  *
  92  * If -c is not set, an attempt will be made to open the default
  93  * root configuration file.  If -c is set and the file is not found, the
  94  * server exits with an error.
  95  *
  96  */
  97
  98 #include "libbb.h"
  99 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
 100 #include <sys/sendfile.h>
 101 #endif
 102
 103 //#define DEBUG 1
 104 #define DEBUG 0
 105
 106 #define IOBUF_SIZE 8192    /* IO buffer */
 107
 108 /* amount of buffering in a pipe */
 109 #ifndef PIPE_BUF
 110 # define PIPE_BUF 4096
 111 #endif
 112 #if PIPE_BUF >= IOBUF_SIZE
 113 # error "PIPE_BUF >= IOBUF_SIZE"
 114 #endif
 115
 116 #define HEADER_READ_TIMEOUT 60
 117
 118 static const char default_path_httpd_conf[] ALIGN1 = "/etc";
 119 static const char httpd_conf[] ALIGN1 = "httpd.conf";
 120 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
 121
 122 typedef struct has_next_ptr {
 123         struct has_next_ptr *next;
 124 } has_next_ptr;
 125
 126 /* Must have "next" as a first member */
 127 typedef struct Htaccess {
 128         struct Htaccess *next;
 129         char *after_colon;
 130         char before_colon[1];  /* really bigger, must be last */
 131 } Htaccess;
 132
 133 /* Must have "next" as a first member */
 134 typedef struct Htaccess_IP {
 135         struct Htaccess_IP *next;
 136         unsigned ip;
 137         unsigned mask;
 138         int allow_deny;
 139 } Htaccess_IP;
 140
 141 /* Must have "next" as a first member */
 142 typedef struct Htaccess_Proxy {
 143         struct Htaccess_Proxy *next;
 144         char *url_from;
 145         char *host_port;
 146         char *url_to;
 147 } Htaccess_Proxy;
 148
 149 enum {
 150         HTTP_OK = 200,
 151         HTTP_PARTIAL_CONTENT = 206,
 152         HTTP_MOVED_TEMPORARILY = 302,
 153         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
 154         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
 155         HTTP_NOT_FOUND = 404,
 156         HTTP_FORBIDDEN = 403,
 157         HTTP_REQUEST_TIMEOUT = 408,
 158         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
 159         HTTP_INTERNAL_SERVER_ERROR = 500,
 160         HTTP_CONTINUE = 100,
 161 #if 0   /* future use */
 162         HTTP_SWITCHING_PROTOCOLS = 101,
 163         HTTP_CREATED = 201,
 164         HTTP_ACCEPTED = 202,
 165         HTTP_NON_AUTHORITATIVE_INFO = 203,
 166         HTTP_NO_CONTENT = 204,
 167         HTTP_MULTIPLE_CHOICES = 300,
 168         HTTP_MOVED_PERMANENTLY = 301,
 169         HTTP_NOT_MODIFIED = 304,
 170         HTTP_PAYMENT_REQUIRED = 402,
 171         HTTP_BAD_GATEWAY = 502,
 172         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
 173         HTTP_RESPONSE_SETSIZE = 0xffffffff
 174 #endif
 175 };
 176
 177 static const uint16_t http_response_type[] ALIGN2 = {
 178         HTTP_OK,
 179 #if ENABLE_FEATURE_HTTPD_RANGES
 180         HTTP_PARTIAL_CONTENT,
 181 #endif
 182         HTTP_MOVED_TEMPORARILY,
 183         HTTP_REQUEST_TIMEOUT,
 184         HTTP_NOT_IMPLEMENTED,
 185 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 186         HTTP_UNAUTHORIZED,
 187 #endif
 188         HTTP_NOT_FOUND,
 189         HTTP_BAD_REQUEST,
 190         HTTP_FORBIDDEN,
 191         HTTP_INTERNAL_SERVER_ERROR,
 192 #if 0   /* not implemented */
 193         HTTP_CREATED,
 194         HTTP_ACCEPTED,
 195         HTTP_NO_CONTENT,
 196         HTTP_MULTIPLE_CHOICES,
 197         HTTP_MOVED_PERMANENTLY,
 198         HTTP_NOT_MODIFIED,
 199         HTTP_BAD_GATEWAY,
 200         HTTP_SERVICE_UNAVAILABLE,
 201 #endif
 202 };
 203
 204 static const struct {
 205         const char *name;
 206         const char *info;
 207 } http_response[ARRAY_SIZE(http_response_type)] = {
 208         { "OK", NULL },
 209 #if ENABLE_FEATURE_HTTPD_RANGES
 210         { "Partial Content", NULL },
 211 #endif
 212         { "Found", NULL },
 213         { "Request Timeout", "No request appeared within 60 seconds" },
 214         { "Not Implemented", "The requested method is not recognized" },
 215 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 216         { "Unauthorized", "" },
 217 #endif
 218         { "Not Found", "The requested URL was not found" },
 219         { "Bad Request", "Unsupported method" },
 220         { "Forbidden", ""  },
 221         { "Internal Server Error", "Internal Server Error" },
 222 #if 0   /* not implemented */
 223         { "Created" },
 224         { "Accepted" },
 225         { "No Content" },
 226         { "Multiple Choices" },
 227         { "Moved Permanently" },
 228         { "Not Modified" },
 229         { "Bad Gateway", "" },
 230         { "Service Unavailable", "" },
 231 #endif
 232 };
 233
 234
 235 struct globals {
 236         int verbose;            /* must be int (used by getopt32) */
 237         smallint flg_deny_all;
 238
 239         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
 240         time_t last_mod;
 241         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
 242         const char *bind_addr_or_port;
 243
 244         const char *g_query;
 245         const char *configFile;
 246         const char *home_httpd;
 247         const char *index_page;
 248
 249         const char *found_mime_type;
 250         const char *found_moved_temporarily;
 251         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 252
 253         USE_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
 254         USE_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
 255         USE_FEATURE_HTTPD_CGI(char *referer;)
 256         USE_FEATURE_HTTPD_CGI(char *user_agent;)
 257         USE_FEATURE_HTTPD_CGI(char *http_accept;)
 258         USE_FEATURE_HTTPD_CGI(char *http_accept_language;)
 259
 260         off_t file_size;        /* -1 - unknown */
 261 #if ENABLE_FEATURE_HTTPD_RANGES
 262         off_t range_start;
 263         off_t range_end;
 264         off_t range_len;
 265 #endif
 266
 267 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 268         Htaccess *g_auth;       /* config user:password lines */
 269 #endif
 270 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 271         Htaccess *mime_a;       /* config mime types */
 272 #endif
 273 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 274         Htaccess *script_i;     /* config script interpreters */
 275 #endif
 276         char *iobuf;            /* [IOBUF_SIZE] */
 277 #define hdr_buf bb_common_bufsiz1
 278         char *hdr_ptr;
 279         int hdr_cnt;
 280 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 281         const char *http_error_page[ARRAY_SIZE(http_response_type)];
 282 #endif
 283 #if ENABLE_FEATURE_HTTPD_PROXY
 284         Htaccess_Proxy *proxy;
 285 #endif
 286 };
 287 #define G (*ptr_to_globals)
 288 #define verbose           (G.verbose          )
 289 #define flg_deny_all      (G.flg_deny_all     )
 290 #define rmt_ip            (G.rmt_ip           )
 291 #define bind_addr_or_port (G.bind_addr_or_port)
 292 #define g_query           (G.g_query          )
 293 #define configFile        (G.configFile       )
 294 #define home_httpd        (G.home_httpd       )
 295 #define index_page        (G.index_page       )
 296 #define found_mime_type   (G.found_mime_type  )
 297 #define found_moved_temporarily (G.found_moved_temporarily)
 298 #define last_mod          (G.last_mod         )
 299 #define ip_a_d            (G.ip_a_d           )
 300 #define g_realm           (G.g_realm          )
 301 #define remoteuser        (G.remoteuser       )
 302 #define referer           (G.referer          )
 303 #define user_agent        (G.user_agent       )
 304 #define http_accept       (G.http_accept      )
 305 #define http_accept_language (G.http_accept_language)
 306 #define file_size         (G.file_size        )
 307 #if ENABLE_FEATURE_HTTPD_RANGES
 308 #define range_start       (G.range_start      )
 309 #define range_end         (G.range_end        )
 310 #define range_len         (G.range_len        )
 311 #endif
 312 #define rmt_ip_str        (G.rmt_ip_str       )
 313 #define g_auth            (G.g_auth           )
 314 #define mime_a            (G.mime_a           )
 315 #define script_i          (G.script_i         )
 316 #define iobuf             (G.iobuf            )
 317 #define hdr_ptr           (G.hdr_ptr          )
 318 #define hdr_cnt           (G.hdr_cnt          )
 319 #define http_error_page   (G.http_error_page  )
 320 #define proxy             (G.proxy            )
 321 #define INIT_G() do { \
 322         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 323         USE_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
 324         bind_addr_or_port = "80"; \
 325         index_page = "index.html"; \
 326         file_size = -1; \
 327 } while (0)
 328
 329 #if !ENABLE_FEATURE_HTTPD_RANGES
 330 enum {
 331         range_start = 0,
 332         range_end = MAXINT(off_t) - 1,
 333         range_len = MAXINT(off_t),
 334 };
 335 #endif
 336
 337
 338 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
 339
 340 /* Prototypes */
 341 enum {
 342         SEND_HEADERS     = (1 << 0),
 343         SEND_BODY        = (1 << 1),
 344         SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
 345 };
 346 static void send_file_and_exit(const char *url, int what) NORETURN;
 347
 348 static void free_llist(has_next_ptr **pptr)
 349 {
 350         has_next_ptr *cur = *pptr;
 351         while (cur) {
 352                 has_next_ptr *t = cur;
 353                 cur = cur->next;
 354                 free(t);
 355         }
 356         *pptr = NULL;
 357 }
 358
 359 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 360  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 361  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 362 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 363 {
 364         free_llist((has_next_ptr**)pptr);
 365 }
 366 #endif
 367
 368 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 369 {
 370         free_llist((has_next_ptr**)pptr);
 371 }
 372
 373 /* Returns presumed mask width in bits or < 0 on error.
 374  * Updates strp, stores IP at provided pointer */
 375 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 376 {
 377         const char *p = *strp;
 378         int auto_mask = 8;
 379         unsigned ip = 0;
 380         int j;
 381
 382         if (*p == '/')
 383                 return -auto_mask;
 384
 385         for (j = 0; j < 4; j++) {
 386                 unsigned octet;
 387
 388                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
 389                         return -auto_mask;
 390                 octet = 0;
 391                 while (*p >= '0' && *p <= '9') {
 392                         octet *= 10;
 393                         octet += *p - '0';
 394                         if (octet > 255)
 395                                 return -auto_mask;
 396                         p++;
 397                 }
 398                 if (*p == '.')
 399                         p++;
 400                 if (*p != '/' && *p)
 401                         auto_mask += 8;
 402                 ip = (ip << 8) | octet;
 403         }
 404         if (*p) {
 405                 if (*p != endc)
 406                         return -auto_mask;
 407                 p++;
 408                 if (*p == '\0')
 409                         return -auto_mask;
 410         }
 411         *ipp = ip;
 412         *strp = p;
 413         return auto_mask;
 414 }
 415
 416 /* Returns 0 on success. Stores IP and mask at provided pointers */
 417 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 418 {
 419         int i;
 420         unsigned mask;
 421         char *p;
 422
 423         i = scan_ip(&str, ipp, '/');
 424         if (i < 0)
 425                 return i;
 426
 427         if (*str) {
 428                 /* there is /xxx after dotted-IP address */
 429                 i = bb_strtou(str, &p, 10);
 430                 if (*p == '.') {
 431                         /* 'xxx' itself is dotted-IP mask, parse it */
 432                         /* (return 0 (success) only if it has N.N.N.N form) */
 433                         return scan_ip(&str, maskp, '\0') - 32;
 434                 }
 435                 if (*p)
 436                         return -1;
 437         }
 438
 439         if (i > 32)
 440                 return -1;
 441
 442         if (sizeof(unsigned) == 4 && i == 32) {
 443                 /* mask >>= 32 below may not work */
 444                 mask = 0;
 445         } else {
 446                 mask = 0xffffffff;
 447                 mask >>= i;
 448         }
 449         /* i == 0 -> *maskp = 0x00000000
 450          * i == 1 -> *maskp = 0x80000000
 451          * i == 4 -> *maskp = 0xf0000000
 452          * i == 31 -> *maskp = 0xfffffffe
 453          * i == 32 -> *maskp = 0xffffffff */
 454         *maskp = (uint32_t)(~mask);
 455         return 0;
 456 }
 457
 458 /*
 459  * Parse configuration file into in-memory linked list.
 460  *
 461  * The first non-white character is examined to determine if the config line
 462  * is one of the following:
 463  *    .ext:mime/type   # new mime type not compiled into httpd
 464  *    [adAD]:from      # ip address allow/deny, * for wildcard
 465  *    /path:user:pass  # username/password
 466  *    Ennn:error.html  # error page for status nnn
 467  *    P:/url:[http://]hostname[:port]/new/path # reverse proxy
 468  *
 469  * Any previous IP rules are discarded.
 470  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
 471  * are also discarded.  That is, previous settings are retained if flag is
 472  * SUBDIR_PARSE.
 473  * Error pages are only parsed on the main config file.
 474  *
 475  * path   Path where to look for httpd.conf (without filename).
 476  * flag   Type of the parse request.
 477  */
 478 /* flag */
 479 #define FIRST_PARSE          0
 480 #define SUBDIR_PARSE         1
 481 #define SIGNALED_PARSE       2
 482 #define FIND_FROM_HTTPD_ROOT 3
 483 static void parse_conf(const char *path, int flag)
 484 {
 485         FILE *f;
 486 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 487         Htaccess *prev;
 488 #endif
 489 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 490  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 491  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 492         Htaccess *cur;
 493 #endif
 494         const char *filename = configFile;
 495         char buf[160];
 496         char *p, *p0;
 497         char *after_colon;
 498         Htaccess_IP *pip;
 499
 500         /* discard old rules */
 501         free_Htaccess_IP_list(&ip_a_d);
 502         flg_deny_all = 0;
 503 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 504  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 505  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 506         /* retain previous auth and mime config only for subdir parse */
 507         if (flag != SUBDIR_PARSE) {
 508 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 509                 free_Htaccess_list(&g_auth);
 510 #endif
 511 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 512                 free_Htaccess_list(&mime_a);
 513 #endif
 514 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 515                 free_Htaccess_list(&script_i);
 516 #endif
 517         }
 518 #endif
 519
 520         if (flag == SUBDIR_PARSE || filename == NULL) {
 521                 filename = alloca(strlen(path) + sizeof(httpd_conf) + 2);
 522                 sprintf((char *)filename, "%s/%s", path, httpd_conf);
 523         }
 524
 525         while ((f = fopen_for_read(filename)) == NULL) {
 526                 if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) {
 527                         /* config file not found, no changes to config */
 528                         return;
 529                 }
 530                 if (configFile && flag == FIRST_PARSE) /* if -c option given */
 531                         bb_simple_perror_msg_and_die(filename);
 532                 flag = FIND_FROM_HTTPD_ROOT;
 533                 filename = httpd_conf;
 534         }
 535
 536 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 537         prev = g_auth;
 538 #endif
 539         /* This could stand some work */
 540         while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) {
 541                 after_colon = NULL;
 542                 for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) {
 543                         if (!isspace(*p0)) {
 544                                 *p++ = *p0;
 545                                 if (*p0 == ':' && after_colon == NULL)
 546                                         after_colon = p;
 547                         }
 548                 }
 549                 *p = '\0';
 550
 551                 /* test for empty or strange line */
 552                 if (after_colon == NULL || *after_colon == '\0')
 553                         continue;
 554                 p0 = buf;
 555                 if (*p0 == 'd' || *p0 == 'a')
 556                         *p0 -= 0x20; /* a/d -> A/D */
 557                 if (*after_colon == '*') {
 558                         if (*p0 == 'D') {
 559                                 /* memorize "deny all" */
 560                                 flg_deny_all = 1;
 561                         }
 562                         /* skip assumed "A:*", it is a default anyway */
 563                         continue;
 564                 }
 565
 566                 if (*p0 == 'A' || *p0 == 'D') {
 567                         /* storing current config IP line */
 568                         pip = xzalloc(sizeof(Htaccess_IP));
 569                         if (scan_ip_mask(after_colon, &(pip->ip), &(pip->mask))) {
 570                                 /* IP{/mask} syntax error detected, protect all */
 571                                 *p0 = 'D';
 572                                 pip->mask = 0;
 573                         }
 574                         pip->allow_deny = *p0;
 575                         if (*p0 == 'D') {
 576                                 /* Deny:from_IP - prepend */
 577                                 pip->next = ip_a_d;
 578                                 ip_a_d = pip;
 579                         } else {
 580                                 /* A:from_IP - append (thus D precedes A) */
 581                                 Htaccess_IP *prev_IP = ip_a_d;
 582                                 if (prev_IP == NULL) {
 583                                         ip_a_d = pip;
 584                                 } else {
 585                                         while (prev_IP->next)
 586                                                 prev_IP = prev_IP->next;
 587                                         prev_IP->next = pip;
 588                                 }
 589                         }
 590                         continue;
 591                 }
 592
 593 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 594                 if (flag == FIRST_PARSE && *p0 == 'E') {
 595                         unsigned i;
 596                         int status = atoi(++p0); /* error status code */
 597                         if (status < HTTP_CONTINUE) {
 598                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 599                                 continue;
 600                         }
 601                         /* then error page; find matching status */
 602                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 603                                 if (http_response_type[i] == status) {
 604                                         /* We chdir to home_httpd, thus no need to
 605                                          * concat_path_file(home_httpd, after_colon)
 606                                          * here */
 607                                         http_error_page[i] = xstrdup(after_colon);
 608                                         break;
 609                                 }
 610                         }
 611                         continue;
 612                 }
 613 #endif
 614
 615 #if ENABLE_FEATURE_HTTPD_PROXY
 616                 if (flag == FIRST_PARSE && *p0 == 'P') {
 617                         /* P:/url:[http://]hostname[:port]/new/path */
 618                         char *url_from, *host_port, *url_to;
 619                         Htaccess_Proxy *proxy_entry;
 620
 621                         url_from = after_colon;
 622                         host_port = strchr(after_colon, ':');
 623                         if (host_port == NULL) {
 624                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 625                                 continue;
 626                         }
 627                         *host_port++ = '\0';
 628                         if (strncmp(host_port, "http://", 7) == 0)
 629                                 host_port += 7;
 630                         if (*host_port == '\0') {
 631                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 632                                 continue;
 633                         }
 634                         url_to = strchr(host_port, '/');
 635                         if (url_to == NULL) {
 636                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 637                                 continue;
 638                         }
 639                         *url_to = '\0';
 640                         proxy_entry = xzalloc(sizeof(Htaccess_Proxy));
 641                         proxy_entry->url_from = xstrdup(url_from);
 642                         proxy_entry->host_port = xstrdup(host_port);
 643                         *url_to = '/';
 644                         proxy_entry->url_to = xstrdup(url_to);
 645                         proxy_entry->next = proxy;
 646                         proxy = proxy_entry;
 647                         continue;
 648                 }
 649 #endif
 650
 651 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 652                 if (*p0 == '/') {
 653                         /* make full path from httpd root / current_path / config_line_path */
 654                         const char *tp = (flag == SUBDIR_PARSE ? path : "");
 655                         p0 = xmalloc(strlen(tp) + (after_colon - buf) + 2 + strlen(after_colon));
 656                         after_colon[-1] = '\0';
 657                         sprintf(p0, "/%s%s", tp, buf);
 658
 659                         /* looks like bb_simplify_path... */
 660                         tp = p = p0;
 661                         do {
 662                                 if (*p == '/') {
 663                                         if (*tp == '/') {    /* skip duplicate (or initial) slash */
 664                                                 continue;
 665                                         }
 666                                         if (*tp == '.') {
 667                                                 if (tp[1] == '/' || tp[1] == '\0') { /* remove extra '.' */
 668                                                         continue;
 669                                                 }
 670                                                 if ((tp[1] == '.') && (tp[2] == '/' || tp[2] == '\0')) {
 671                                                         ++tp;
 672                                                         if (p > p0) {
 673                                                                 while (*--p != '/') /* omit previous dir */
 674                                                                         continue;
 675                                                         }
 676                                                         continue;
 677                                                 }
 678                                         }
 679                                 }
 680                                 *++p = *tp;
 681                         } while (*++tp);
 682
 683                         if ((p == p0) || (*p != '/')) { /* not a trailing slash */
 684                                 ++p;                    /* so keep last character */
 685                         }
 686                         *p = ':';
 687                         strcpy(p + 1, after_colon);
 688                 }
 689 #endif
 690                 if (*p0 == 'I') {
 691                         index_page = xstrdup(after_colon);
 692                         continue;
 693                 }
 694
 695                 /* Do not allow jumping around using H in subdir's configs */
 696                 if (flag == FIRST_PARSE && *p0 == 'H') {
 697                         home_httpd = xstrdup(after_colon);
 698                         xchdir(home_httpd);
 699                         continue;
 700                 }
 701
 702 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 703  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 704  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 705                 /* storing current config line */
 706                 cur = xzalloc(sizeof(Htaccess) + strlen(p0));
 707                 strcpy(cur->before_colon, p0);
 708 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 709                 if (*p0 == '/') /* was malloced - see above */
 710                         free(p0);
 711 #endif
 712                 cur->after_colon = strchr(cur->before_colon, ':');
 713                 *cur->after_colon++ = '\0';
 714 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 715                 if (cur->before_colon[0] == '.') {
 716                         /* .mime line: prepend to mime_a list */
 717                         cur->next = mime_a;
 718                         mime_a = cur;
 719                         continue;
 720                 }
 721 #endif
 722 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 723                 if (cur->before_colon[0] == '*' && cur->before_colon[1] == '.') {
 724                         /* script interpreter line: prepend to script_i list */
 725                         cur->next = script_i;
 726                         script_i = cur;
 727                         continue;
 728                 }
 729 #endif
 730 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 731 //TODO: we do not test for leading "/"??
 732 //also, do we leak cur if BASIC_AUTH is off?
 733                 if (prev == NULL) {
 734                         /* first line */
 735                         g_auth = prev = cur;
 736                 } else {
 737                         /* sort path, if current length eq or bigger then move up */
 738                         Htaccess *prev_hti = g_auth;
 739                         size_t l = strlen(cur->before_colon);
 740                         Htaccess *hti;
 741
 742                         for (hti = prev_hti; hti; hti = hti->next) {
 743                                 if (l >= strlen(hti->before_colon)) {
 744                                         /* insert before hti */
 745                                         cur->next = hti;
 746                                         if (prev_hti != hti) {
 747                                                 prev_hti->next = cur;
 748                                         } else {
 749                                                 /* insert as top */
 750                                                 g_auth = cur;
 751                                         }
 752                                         break;
 753                                 }
 754                                 if (prev_hti != hti)
 755                                         prev_hti = prev_hti->next;
 756                         }
 757                         if (!hti) {       /* not inserted, add to bottom */
 758                                 prev->next = cur;
 759                                 prev = cur;
 760                         }
 761                 }
 762 #endif /* BASIC_AUTH */
 763 #endif /* BASIC_AUTH || MIME_TYPES || SCRIPT_INTERPR */
 764          } /* while (fgets) */
 765          fclose(f);
 766 }
 767
 768 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
 769 /*
 770  * Given a string, html-encode special characters.
 771  * This is used for the -e command line option to provide an easy way
 772  * for scripts to encode result data without confusing browsers.  The
 773  * returned string pointer is memory allocated by malloc().
 774  *
 775  * Returns a pointer to the encoded string (malloced).
 776  */
 777 static char *encodeString(const char *string)
 778 {
 779         /* take the simple route and encode everything */
 780         /* could possibly scan once to get length.     */
 781         int len = strlen(string);
 782         char *out = xmalloc(len * 6 + 1);
 783         char *p = out;
 784         char ch;
 785
 786         while ((ch = *string++)) {
 787                 /* very simple check for what to encode */
 788                 if (isalnum(ch))
 789                         *p++ = ch;
 790                 else
 791                         p += sprintf(p, "&#%d;", (unsigned char) ch);
 792         }
 793         *p = '\0';
 794         return out;
 795 }
 796 #endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
 797
 798 /*
 799  * Given a URL encoded string, convert it to plain ascii.
 800  * Since decoding always makes strings smaller, the decode is done in-place.
 801  * Thus, callers should xstrdup() the argument if they do not want the
 802  * argument modified.  The return is the original pointer, allowing this
 803  * function to be easily used as arguments to other functions.
 804  *
 805  * string    The first string to decode.
 806  * option_d  1 if called for httpd -d
 807  *
 808  * Returns a pointer to the decoded string (same as input).
 809  */
 810 static unsigned hex_to_bin(unsigned char c)
 811 {
 812         unsigned v;
 813
 814         v = c - '0';
 815         if (v <= 9)
 816                 return v;
 817         /* c | 0x20: letters to lower case, non-letters
 818          * to (potentially different) non-letters */
 819         v = (unsigned)(c | 0x20) - 'a';
 820         if (v <= 5)
 821                 return v + 10;
 822         return ~0;
 823 }
 824 /* For testing:
 825 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
 826 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 827 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 828 */
 829 static char *decodeString(char *orig, int option_d)
 830 {
 831         /* note that decoded string is always shorter than original */
 832         char *string = orig;
 833         char *ptr = string;
 834         char c;
 835
 836         while ((c = *ptr++) != '\0') {
 837                 unsigned v;
 838
 839                 if (option_d && c == '+') {
 840                         *string++ = ' ';
 841                         continue;
 842                 }
 843                 if (c != '%') {
 844                         *string++ = c;
 845                         continue;
 846                 }
 847                 v = hex_to_bin(ptr[0]);
 848                 if (v > 15) {
 849  bad_hex:
 850                         if (!option_d)
 851                                 return NULL;
 852                         *string++ = '%';
 853                         continue;
 854                 }
 855                 v = (v * 16) | hex_to_bin(ptr[1]);
 856                 if (v > 255)
 857                         goto bad_hex;
 858                 if (!option_d && (v == '/' || v == '\0')) {
 859                         /* caller takes it as indication of invalid
 860                          * (dangerous wrt exploits) chars */
 861                         return orig + 1;
 862                 }
 863                 *string++ = v;
 864                 ptr += 2;
 865         }
 866         *string = '\0';
 867         return orig;
 868 }
 869
 870 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 871 /*
 872  * Decode a base64 data stream as per rfc1521.
 873  * Note that the rfc states that non base64 chars are to be ignored.
 874  * Since the decode always results in a shorter size than the input,
 875  * it is OK to pass the input arg as an output arg.
 876  * Parameter: a pointer to a base64 encoded string.
 877  * Decoded data is stored in-place.
 878  */
 879 static void decodeBase64(char *Data)
 880 {
 881         const unsigned char *in = (const unsigned char *)Data;
 882         /* The decoded size will be at most 3/4 the size of the encoded */
 883         unsigned ch = 0;
 884         int i = 0;
 885
 886         while (*in) {
 887                 int t = *in++;
 888
 889                 if (t >= '0' && t <= '9')
 890                         t = t - '0' + 52;
 891                 else if (t >= 'A' && t <= 'Z')
 892                         t = t - 'A';
 893                 else if (t >= 'a' && t <= 'z')
 894                         t = t - 'a' + 26;
 895                 else if (t == '+')
 896                         t = 62;
 897                 else if (t == '/')
 898                         t = 63;
 899                 else if (t == '=')
 900                         t = 0;
 901                 else
 902                         continue;
 903
 904                 ch = (ch << 6) | t;
 905                 i++;
 906                 if (i == 4) {
 907                         *Data++ = (char) (ch >> 16);
 908                         *Data++ = (char) (ch >> 8);
 909                         *Data++ = (char) ch;
 910                         i = 0;
 911                 }
 912         }
 913         *Data = '\0';
 914 }
 915 #endif
 916
 917 /*
 918  * Create a listen server socket on the designated port.
 919  */
 920 static int openServer(void)
 921 {
 922         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 923         if (!errno && n && n <= 0xffff)
 924                 n = create_and_bind_stream_or_die(NULL, n);
 925         else
 926                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 927         xlisten(n, 9);
 928         return n;
 929 }
 930
 931 /*
 932  * Log the connection closure and exit.
 933  */
 934 static void log_and_exit(void) NORETURN;
 935 static void log_and_exit(void)
 936 {
 937         /* Paranoia. IE said to be buggy. It may send some extra data
 938          * or be confused by us just exiting without SHUT_WR. Oh well. */
 939         shutdown(1, SHUT_WR);
 940         /* Why??
 941         (this also messes up stdin when user runs httpd -i from terminal)
 942         ndelay_on(0);
 943         while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
 944                 continue;
 945         */
 946
 947         if (verbose > 2)
 948                 bb_error_msg("closed");
 949         _exit(xfunc_error_retval);
 950 }
 951
 952 /*
 953  * Create and send HTTP response headers.
 954  * The arguments are combined and sent as one write operation.  Note that
 955  * IE will puke big-time if the headers are not sent in one packet and the
 956  * second packet is delayed for any reason.
 957  * responseNum - the result code to send.
 958  */
 959 static void send_headers(int responseNum)
 960 {
 961         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 962
 963         const char *responseString = "";
 964         const char *infoString = NULL;
 965         const char *mime_type;
 966 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 967         const char *error_page = NULL;
 968 #endif
 969         unsigned i;
 970         time_t timer = time(0);
 971         char tmp_str[80];
 972         int len;
 973
 974         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 975                 if (http_response_type[i] == responseNum) {
 976                         responseString = http_response[i].name;
 977                         infoString = http_response[i].info;
 978 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 979                         error_page = http_error_page[i];
 980 #endif
 981                         break;
 982                 }
 983         }
 984         /* error message is HTML */
 985         mime_type = responseNum == HTTP_OK ?
 986                                 found_mime_type : "text/html";
 987
 988         if (verbose)
 989                 bb_error_msg("response:%u", responseNum);
 990
 991         /* emit the current date */
 992         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
 993         len = sprintf(iobuf,
 994                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
 995                         "Date: %s\r\nConnection: close\r\n",
 996                         responseNum, responseString, mime_type, tmp_str);
 997
 998 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 999         if (responseNum == HTTP_UNAUTHORIZED) {
1000                 len += sprintf(iobuf + len,
1001                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
1002                                 g_realm);
1003         }
1004 #endif
1005         if (responseNum == HTTP_MOVED_TEMPORARILY) {
1006                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
1007                                 found_moved_temporarily,
1008                                 (g_query ? "?" : ""),
1009                                 (g_query ? g_query : ""));
1010         }
1011
1012 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1013         if (error_page && access(error_page, R_OK) == 0) {
1014                 strcat(iobuf, "\r\n");
1015                 len += 2;
1016
1017                 if (DEBUG)
1018                         fprintf(stderr, "headers: '%s'\n", iobuf);
1019                 full_write(STDOUT_FILENO, iobuf, len);
1020                 if (DEBUG)
1021                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1022                 return send_file_and_exit(error_page, SEND_BODY);
1023         }
1024 #endif
1025
1026         if (file_size != -1) {    /* file */
1027                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1028 #if ENABLE_FEATURE_HTTPD_RANGES
1029                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1030                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"d-%"OFF_FMT"d/%"OFF_FMT"d\r\n",
1031                                         range_start,
1032                                         range_end,
1033                                         file_size);
1034                         file_size = range_end - range_start + 1;
1035                 }
1036 #endif
1037                 len += sprintf(iobuf + len,
1038 #if ENABLE_FEATURE_HTTPD_RANGES
1039                         "Accept-Ranges: bytes\r\n"
1040 #endif
1041                         "Last-Modified: %s\r\n%s %"OFF_FMT"d\r\n",
1042                                 tmp_str,
1043                                 "Content-length:",
1044                                 file_size
1045                 );
1046         }
1047         iobuf[len++] = '\r';
1048         iobuf[len++] = '\n';
1049         if (infoString) {
1050                 len += sprintf(iobuf + len,
1051                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1052                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1053                                 responseNum, responseString,
1054                                 responseNum, responseString, infoString);
1055         }
1056         if (DEBUG)
1057                 fprintf(stderr, "headers: '%s'\n", iobuf);
1058         if (full_write(STDOUT_FILENO, iobuf, len) != len) {
1059                 if (verbose > 1)
1060                         bb_perror_msg("error");
1061                 log_and_exit();
1062         }
1063 }
1064
1065 static void send_headers_and_exit(int responseNum) NORETURN;
1066 static void send_headers_and_exit(int responseNum)
1067 {
1068         send_headers(responseNum);
1069         log_and_exit();
1070 }
1071
1072 /*
1073  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1074  * '\n' is replaced with NUL.
1075  * Return number of characters read or 0 if nothing is read
1076  * ('\r' and '\n' are not counted).
1077  * Data is returned in iobuf.
1078  */
1079 static int get_line(void)
1080 {
1081         int count = 0;
1082         char c;
1083
1084         while (1) {
1085                 if (hdr_cnt <= 0) {
1086                         hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1087                         if (hdr_cnt <= 0)
1088                                 break;
1089                         hdr_ptr = hdr_buf;
1090                 }
1091                 iobuf[count] = c = *hdr_ptr++;
1092                 hdr_cnt--;
1093
1094                 if (c == '\r')
1095                         continue;
1096                 if (c == '\n') {
1097                         iobuf[count] = '\0';
1098                         return count;
1099                 }
1100                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1101                         count++;
1102         }
1103         return count;
1104 }
1105
1106 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1107
1108 /* gcc 4.2.1 fares better with NOINLINE */
1109 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
1110 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1111 {
1112         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1113         struct pollfd pfd[3];
1114         int out_cnt; /* we buffer a bit of initial CGI output */
1115         int count;
1116
1117         /* iobuf is used for CGI -> network data,
1118          * hdr_buf is for network -> CGI data (POSTDATA) */
1119
1120         /* If CGI dies, we still want to correctly finish reading its output
1121          * and send it to the peer. So please no SIGPIPEs! */
1122         signal(SIGPIPE, SIG_IGN);
1123
1124         // We inconsistently handle a case when more POSTDATA from network
1125         // is coming than we expected. We may give *some part* of that
1126         // extra data to CGI.
1127
1128         //if (hdr_cnt > post_len) {
1129         //      /* We got more POSTDATA from network than we expected */
1130         //      hdr_cnt = post_len;
1131         //}
1132         post_len -= hdr_cnt;
1133         /* post_len - number of POST bytes not yet read from network */
1134
1135         /* NB: breaking out of this loop jumps to log_and_exit() */
1136         out_cnt = 0;
1137         while (1) {
1138                 memset(pfd, 0, sizeof(pfd));
1139
1140                 pfd[FROM_CGI].fd = fromCgi_rd;
1141                 pfd[FROM_CGI].events = POLLIN;
1142
1143                 if (toCgi_wr) {
1144                         pfd[TO_CGI].fd = toCgi_wr;
1145                         if (hdr_cnt > 0) {
1146                                 pfd[TO_CGI].events = POLLOUT;
1147                         } else if (post_len > 0) {
1148                                 pfd[0].events = POLLIN;
1149                         } else {
1150                                 /* post_len <= 0 && hdr_cnt <= 0:
1151                                  * no more POST data to CGI,
1152                                  * let CGI see EOF on CGI's stdin */
1153                                 close(toCgi_wr);
1154                                 toCgi_wr = 0;
1155                         }
1156                 }
1157
1158                 /* Now wait on the set of sockets */
1159                 count = safe_poll(pfd, 3, -1);
1160                 if (count <= 0) {
1161 #if 0
1162                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1163                                 /* Weird. CGI didn't exit and no fd's
1164                                  * are ready, yet poll returned?! */
1165                                 continue;
1166                         }
1167                         if (DEBUG && WIFEXITED(status))
1168                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1169                         if (DEBUG && WIFSIGNALED(status))
1170                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1171 #endif
1172                         break;
1173                 }
1174
1175                 if (pfd[TO_CGI].revents) {
1176                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1177                         /* Have data from peer and can write to CGI */
1178                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1179                         /* Doesn't happen, we dont use nonblocking IO here
1180                          *if (count < 0 && errno == EAGAIN) {
1181                          *      ...
1182                          *} else */
1183                         if (count > 0) {
1184                                 hdr_ptr += count;
1185                                 hdr_cnt -= count;
1186                         } else {
1187                                 /* EOF/broken pipe to CGI, stop piping POST data */
1188                                 hdr_cnt = post_len = 0;
1189                         }
1190                 }
1191
1192                 if (pfd[0].revents) {
1193                         /* post_len > 0 && hdr_cnt == 0 here */
1194                         /* We expect data, prev data portion is eaten by CGI
1195                          * and there *is* data to read from the peer
1196                          * (POSTDATA) */
1197                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1198                         //count = safe_read(STDIN_FILENO, hdr_buf, count);
1199                         count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1200                         if (count > 0) {
1201                                 hdr_cnt = count;
1202                                 hdr_ptr = hdr_buf;
1203                                 post_len -= count;
1204                         } else {
1205                                 /* no more POST data can be read */
1206                                 post_len = 0;
1207                         }
1208                 }
1209
1210                 if (pfd[FROM_CGI].revents) {
1211                         /* There is something to read from CGI */
1212                         char *rbuf = iobuf;
1213
1214                         /* Are we still buffering CGI output? */
1215                         if (out_cnt >= 0) {
1216                                 /* HTTP_200[] has single "\r\n" at the end.
1217                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1218                                  * CGI scripts MUST send their own header terminated by
1219                                  * empty line, then data. That's why we have only one
1220                                  * <cr><lf> pair here. We will output "200 OK" line
1221                                  * if needed, but CGI still has to provide blank line
1222                                  * between header and body */
1223
1224                                 /* Must use safe_read, not full_read, because
1225                                  * CGI may output a few first bytes and then wait
1226                                  * for POSTDATA without closing stdout.
1227                                  * With full_read we may wait here forever. */
1228                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1229                                 if (count <= 0) {
1230                                         /* eof (or error) and there was no "HTTP",
1231                                          * so write it, then write received data */
1232                                         if (out_cnt) {
1233                                                 full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
1234                                                 full_write(STDOUT_FILENO, rbuf, out_cnt);
1235                                         }
1236                                         break; /* CGI stdout is closed, exiting */
1237                                 }
1238                                 out_cnt += count;
1239                                 count = 0;
1240                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1241                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1242                                         /* send "HTTP/1.0 " */
1243                                         if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
1244                                                 break;
1245                                         rbuf += 8; /* skip "Status: " */
1246                                         count = out_cnt - 8;
1247                                         out_cnt = -1; /* buffering off */
1248                                 } else if (out_cnt >= 4) {
1249                                         /* Did CGI add "HTTP"? */
1250                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1251                                                 /* there is no "HTTP", do it ourself */
1252                                                 if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1253                                                         break;
1254                                         }
1255                                         /* Commented out:
1256                                         if (!strstr(rbuf, "ontent-")) {
1257                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1258                                         }
1259                                          * Counter-example of valid CGI without Content-type:
1260                                          * echo -en "HTTP/1.0 302 Found\r\n"
1261                                          * echo -en "Location: http://www.busybox.net\r\n"
1262                                          * echo -en "\r\n"
1263                                          */
1264                                         count = out_cnt;
1265                                         out_cnt = -1; /* buffering off */
1266                                 }
1267                         } else {
1268                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1269                                 if (count <= 0)
1270                                         break;  /* eof (or error) */
1271                         }
1272                         if (full_write(STDOUT_FILENO, rbuf, count) != count)
1273                                 break;
1274                         if (DEBUG)
1275                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1276                 } /* if (pfd[FROM_CGI].revents) */
1277         } /* while (1) */
1278         log_and_exit();
1279 }
1280 #endif
1281
1282 #if ENABLE_FEATURE_HTTPD_CGI
1283
1284 static void setenv1(const char *name, const char *value)
1285 {
1286         setenv(name, value ? value : "", 1);
1287 }
1288
1289 /*
1290  * Spawn CGI script, forward CGI's stdin/out <=> network
1291  *
1292  * Environment variables are set up and the script is invoked with pipes
1293  * for stdin/stdout.  If a POST is being done the script is fed the POST
1294  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1295  *
1296  * Parameters:
1297  * const char *url              The requested URL (with leading /).
1298  * int post_len                 Length of the POST body.
1299  * const char *cookie           For set HTTP_COOKIE.
1300  * const char *content_type     For set CONTENT_TYPE.
1301  */
1302 static void send_cgi_and_exit(
1303                 const char *url,
1304                 const char *request,
1305                 int post_len,
1306                 const char *cookie,
1307                 const char *content_type) NORETURN;
1308 static void send_cgi_and_exit(
1309                 const char *url,
1310                 const char *request,
1311                 int post_len,
1312                 const char *cookie,
1313                 const char *content_type)
1314 {
1315         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1316         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1317         char *script;
1318         int pid;
1319
1320         /* Make a copy. NB: caller guarantees:
1321          * url[0] == '/', url[1] != '/' */
1322         url = xstrdup(url);
1323
1324         /*
1325          * We are mucking with environment _first_ and then vfork/exec,
1326          * this allows us to use vfork safely. Parent doesn't care about
1327          * these environment changes anyway.
1328          */
1329
1330         /* Check for [dirs/]script.cgi/PATH_INFO */
1331         script = (char*)url;
1332         while ((script = strchr(script + 1, '/')) != NULL) {
1333                 struct stat sb;
1334
1335                 *script = '\0';
1336                 if (!is_directory(url + 1, 1, &sb)) {
1337                         /* not directory, found script.cgi/PATH_INFO */
1338                         *script = '/';
1339                         break;
1340                 }
1341                 *script = '/'; /* is directory, find next '/' */
1342         }
1343         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1344         setenv1("REQUEST_METHOD", request);
1345         if (g_query) {
1346                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1347         } else {
1348                 setenv1("REQUEST_URI", url);
1349         }
1350         if (script != NULL)
1351                 *script = '\0';         /* cut off /PATH_INFO */
1352
1353         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1354         if (home_httpd[0] == '/') {
1355                 char *fullpath = concat_path_file(home_httpd, url);
1356                 setenv1("SCRIPT_FILENAME", fullpath);
1357         }
1358         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1359         setenv1("SCRIPT_NAME", url);
1360         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1361          * QUERY_STRING: The information which follows the ? in the URL
1362          * which referenced this script. This is the query information.
1363          * It should not be decoded in any fashion. This variable
1364          * should always be set when there is query information,
1365          * regardless of command line decoding. */
1366         /* (Older versions of bbox seem to do some decoding) */
1367         setenv1("QUERY_STRING", g_query);
1368         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1369         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1370         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1371         /* Having _separate_ variables for IP and port defeats
1372          * the purpose of having socket abstraction. Which "port"
1373          * are you using on Unix domain socket?
1374          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1375          * Oh well... */
1376         {
1377                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1378                 char *cp = strrchr(p, ':');
1379                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1380                         cp = NULL;
1381                 if (cp) *cp = '\0'; /* delete :PORT */
1382                 setenv1("REMOTE_ADDR", p);
1383                 if (cp) {
1384                         *cp = ':';
1385 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1386                         setenv1("REMOTE_PORT", cp + 1);
1387 #endif
1388                 }
1389         }
1390         setenv1("HTTP_USER_AGENT", user_agent);
1391         if (http_accept)
1392                 setenv1("HTTP_ACCEPT", http_accept);
1393         if (http_accept_language)
1394                 setenv1("HTTP_ACCEPT_LANGUAGE", http_accept_language);
1395         if (post_len)
1396                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1397         if (cookie)
1398                 setenv1("HTTP_COOKIE", cookie);
1399         if (content_type)
1400                 setenv1("CONTENT_TYPE", content_type);
1401 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1402         if (remoteuser) {
1403                 setenv1("REMOTE_USER", remoteuser);
1404                 putenv((char*)"AUTH_TYPE=Basic");
1405         }
1406 #endif
1407         if (referer)
1408                 setenv1("HTTP_REFERER", referer);
1409
1410         xpiped_pair(fromCgi);
1411         xpiped_pair(toCgi);
1412
1413         pid = vfork();
1414         if (pid < 0) {
1415                 /* TODO: log perror? */
1416                 log_and_exit();
1417         }
1418
1419         if (!pid) {
1420                 /* Child process */
1421                 char *argv[3];
1422
1423                 xfunc_error_retval = 242;
1424
1425                 /* NB: close _first_, then move fds! */
1426                 close(toCgi.wr);
1427                 close(fromCgi.rd);
1428                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1429                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1430                 /* User seeing stderr output can be a security problem.
1431                  * If CGI really wants that, it can always do dup itself. */
1432                 /* dup2(1, 2); */
1433
1434                 /* Chdiring to script's dir */
1435                 script = strrchr(url, '/');
1436                 if (script != url) { /* paranoia */
1437                         *script = '\0';
1438                         if (chdir(url + 1) != 0) {
1439                                 bb_perror_msg("chdir %s", url + 1);
1440                                 goto error_execing_cgi;
1441                         }
1442                         // not needed: *script = '/';
1443                 }
1444                 script++;
1445
1446                 /* set argv[0] to name without path */
1447                 argv[0] = script;
1448                 argv[1] = NULL;
1449
1450 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1451                 {
1452                         char *suffix = strrchr(script, '.');
1453
1454                         if (suffix) {
1455                                 Htaccess *cur;
1456                                 for (cur = script_i; cur; cur = cur->next) {
1457                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1458                                                 /* found interpreter name */
1459                                                 argv[0] = cur->after_colon;
1460                                                 argv[1] = script;
1461                                                 argv[2] = NULL;
1462                                                 break;
1463                                         }
1464                                 }
1465                         }
1466                 }
1467 #endif
1468                 /* restore default signal dispositions for CGI process */
1469                 bb_signals(0
1470                         | (1 << SIGCHLD)
1471                         | (1 << SIGPIPE)
1472                         | (1 << SIGHUP)
1473                         , SIG_DFL);
1474
1475                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1476                  * without any dir components and will only match a file
1477                  * in the current directory */
1478                 execv(argv[0], argv);
1479                 if (verbose)
1480                         bb_perror_msg("exec %s", argv[0]);
1481  error_execing_cgi:
1482                 /* send to stdout
1483                  * (we are CGI here, our stdout is pumped to the net) */
1484                 send_headers_and_exit(HTTP_NOT_FOUND);
1485         } /* end child */
1486
1487         /* Parent process */
1488
1489         /* Restore variables possibly changed by child */
1490         xfunc_error_retval = 0;
1491
1492         /* Pump data */
1493         close(fromCgi.wr);
1494         close(toCgi.rd);
1495         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1496 }
1497
1498 #endif          /* FEATURE_HTTPD_CGI */
1499
1500 /*
1501  * Send a file response to a HTTP request, and exit
1502  *
1503  * Parameters:
1504  * const char *url  The requested URL (with leading /).
1505  * what             What to send (headers/body/both).
1506  */
1507 static void send_file_and_exit(const char *url, int what)
1508 {
1509         static const char *const suffixTable[] = {
1510         /* Warning: shorter equivalent suffix in one line must be first */
1511                 ".htm.html", "text/html",
1512                 ".jpg.jpeg", "image/jpeg",
1513                 ".gif",      "image/gif",
1514                 ".png",      "image/png",
1515                 ".txt.h.c.cc.cpp", "text/plain",
1516                 ".css",      "text/css",
1517                 ".wav",      "audio/wav",
1518                 ".avi",      "video/x-msvideo",
1519                 ".qt.mov",   "video/quicktime",
1520                 ".mpe.mpeg", "video/mpeg",
1521                 ".mid.midi", "audio/midi",
1522                 ".mp3",      "audio/mpeg",
1523 #if 0                        /* unpopular */
1524                 ".au",       "audio/basic",
1525                 ".pac",      "application/x-ns-proxy-autoconfig",
1526                 ".vrml.wrl", "model/vrml",
1527 #endif
1528                 NULL
1529         };
1530
1531         char *suffix;
1532         int f;
1533         const char *const *table;
1534         const char *try_suffix;
1535         ssize_t count;
1536 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1537         off_t offset;
1538 #endif
1539
1540         /* If you want to know about EPIPE below
1541          * (happens if you abort downloads from local httpd): */
1542         signal(SIGPIPE, SIG_IGN);
1543
1544         suffix = strrchr(url, '.');
1545
1546         /* If not found, set default as "application/octet-stream";  */
1547         found_mime_type = "application/octet-stream";
1548         if (suffix) {
1549 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1550                 Htaccess *cur;
1551 #endif
1552                 for (table = suffixTable; *table; table += 2) {
1553                         try_suffix = strstr(table[0], suffix);
1554                         if (try_suffix) {
1555                                 try_suffix += strlen(suffix);
1556                                 if (*try_suffix == '\0' || *try_suffix == '.') {
1557                                         found_mime_type = table[1];
1558                                         break;
1559                                 }
1560                         }
1561                 }
1562 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1563                 for (cur = mime_a; cur; cur = cur->next) {
1564                         if (strcmp(cur->before_colon, suffix) == 0) {
1565                                 found_mime_type = cur->after_colon;
1566                                 break;
1567                         }
1568                 }
1569 #endif
1570         }
1571
1572         if (DEBUG)
1573                 bb_error_msg("sending file '%s' content-type: %s",
1574                         url, found_mime_type);
1575
1576         f = open(url, O_RDONLY);
1577         if (f < 0) {
1578                 if (DEBUG)
1579                         bb_perror_msg("can't open '%s'", url);
1580                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1581                  * IOW: it is unsafe to call send_headers_and_exit
1582                  * if what is SEND_BODY! Can recurse! */
1583                 if (what != SEND_BODY)
1584                         send_headers_and_exit(HTTP_NOT_FOUND);
1585                 log_and_exit();
1586         }
1587 #if ENABLE_FEATURE_HTTPD_RANGES
1588         if (what == SEND_BODY)
1589                 range_start = 0; /* err pages and ranges don't mix */
1590         range_len = MAXINT(off_t);
1591         if (range_start) {
1592                 if (!range_end) {
1593                         range_end = file_size - 1;
1594                 }
1595                 if (range_end < range_start
1596                  || lseek(f, range_start, SEEK_SET) != range_start
1597                 ) {
1598                         lseek(f, 0, SEEK_SET);
1599                         range_start = 0;
1600                 } else {
1601                         range_len = range_end - range_start + 1;
1602                         send_headers(HTTP_PARTIAL_CONTENT);
1603                         what = SEND_BODY;
1604                 }
1605         }
1606 #endif
1607
1608         if (what & SEND_HEADERS)
1609                 send_headers(HTTP_OK);
1610
1611 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1612         offset = range_start;
1613         do {
1614                 /* sz is rounded down to 64k */
1615                 ssize_t sz = MAXINT(ssize_t) - 0xffff;
1616                 USE_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1617                 count = sendfile(1, f, &offset, sz);
1618                 if (count < 0) {
1619                         if (offset == range_start)
1620                                 goto fallback;
1621                         goto fin;
1622                 }
1623                 USE_FEATURE_HTTPD_RANGES(range_len -= sz;)
1624         } while (count > 0 && range_len);
1625         log_and_exit();
1626
1627  fallback:
1628 #endif
1629         while ((count = safe_read(f, iobuf, IOBUF_SIZE)) > 0) {
1630                 ssize_t n;
1631                 USE_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1632                 n = full_write(STDOUT_FILENO, iobuf, count);
1633                 if (count != n)
1634                         break;
1635                 USE_FEATURE_HTTPD_RANGES(range_len -= count;)
1636                 if (!range_len)
1637                         break;
1638         }
1639 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1640  fin:
1641 #endif
1642         if (count < 0 && verbose > 1)
1643                 bb_perror_msg("error");
1644         log_and_exit();
1645 }
1646
1647 static int checkPermIP(void)
1648 {
1649         Htaccess_IP *cur;
1650
1651         for (cur = ip_a_d; cur; cur = cur->next) {
1652 #if DEBUG
1653                 fprintf(stderr,
1654                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1655                         rmt_ip_str,
1656                         (unsigned char)(cur->ip >> 24),
1657                         (unsigned char)(cur->ip >> 16),
1658                         (unsigned char)(cur->ip >> 8),
1659                         (unsigned char)(cur->ip),
1660                         (unsigned char)(cur->mask >> 24),
1661                         (unsigned char)(cur->mask >> 16),
1662                         (unsigned char)(cur->mask >> 8),
1663                         (unsigned char)(cur->mask)
1664                 );
1665 #endif
1666                 if ((rmt_ip & cur->mask) == cur->ip)
1667                         return (cur->allow_deny == 'A'); /* A -> 1 */
1668         }
1669
1670         return !flg_deny_all; /* depends on whether we saw "D:*" */
1671 }
1672
1673 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1674 /*
1675  * Config file entries are of the form "/<path>:<user>:<passwd>".
1676  * If config file has no prefix match for path, access is allowed.
1677  *
1678  * path                 The file path
1679  * user_and_passwd      "user:passwd" to validate
1680  *
1681  * Returns 1 if user_and_passwd is OK.
1682  */
1683 static int check_user_passwd(const char *path, const char *user_and_passwd)
1684 {
1685         Htaccess *cur;
1686         const char *prev = NULL;
1687
1688         for (cur = g_auth; cur; cur = cur->next) {
1689                 const char *dir_prefix;
1690                 size_t len;
1691
1692                 dir_prefix = cur->before_colon;
1693
1694                 /* WHY? */
1695                 /* If already saw a match, don't accept other different matches */
1696                 if (prev && strcmp(prev, dir_prefix) != 0)
1697                         continue;
1698
1699                 if (DEBUG)
1700                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
1701
1702                 /* If it's not a prefix match, continue searching */
1703                 len = strlen(dir_prefix);
1704                 if (len != 1 /* dir_prefix "/" matches all, don't need to check */
1705                  && (strncmp(dir_prefix, path, len) != 0
1706                     || (path[len] != '/' && path[len] != '\0'))
1707                 ) {
1708                         continue;
1709                 }
1710
1711                 /* Path match found */
1712                 prev = dir_prefix;
1713
1714                 if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1715                         char *md5_passwd;
1716
1717                         md5_passwd = strchr(cur->after_colon, ':');
1718                         if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
1719                          && md5_passwd[3] == '$' && md5_passwd[4]
1720                         ) {
1721                                 char *encrypted;
1722                                 int r, user_len_p1;
1723
1724                                 md5_passwd++;
1725                                 user_len_p1 = md5_passwd - cur->after_colon;
1726                                 /* comparing "user:" */
1727                                 if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
1728                                         continue;
1729                                 }
1730
1731                                 encrypted = pw_encrypt(
1732                                         user_and_passwd + user_len_p1 /* cleartext pwd from user */,
1733                                         md5_passwd /*salt */, 1 /* cleanup */);
1734                                 r = strcmp(encrypted, md5_passwd);
1735                                 free(encrypted);
1736                                 if (r == 0)
1737                                         goto set_remoteuser_var; /* Ok */
1738                                 continue;
1739                         }
1740                 }
1741
1742                 /* Comparing plaintext "user:pass" in one go */
1743                 if (strcmp(cur->after_colon, user_and_passwd) == 0) {
1744  set_remoteuser_var:
1745                         remoteuser = xstrndup(user_and_passwd,
1746                                         strchrnul(user_and_passwd, ':') - user_and_passwd);
1747                         return 1; /* Ok */
1748                 }
1749         } /* for */
1750
1751         /* 0(bad) if prev is set: matches were found but passwd was wrong */
1752         return (prev == NULL);
1753 }
1754 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1755
1756 #if ENABLE_FEATURE_HTTPD_PROXY
1757 static Htaccess_Proxy *find_proxy_entry(const char *url)
1758 {
1759         Htaccess_Proxy *p;
1760         for (p = proxy; p; p = p->next) {
1761                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1762                         return p;
1763         }
1764         return NULL;
1765 }
1766 #endif
1767
1768 /*
1769  * Handle timeouts
1770  */
1771 static void exit_on_signal(int sig) NORETURN;
1772 static void exit_on_signal(int sig UNUSED_PARAM)
1773 {
1774         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1775 }
1776
1777 /*
1778  * Handle an incoming http request and exit.
1779  */
1780 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
1781 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1782 {
1783         static const char request_GET[] ALIGN1 = "GET";
1784         struct stat sb;
1785         char *urlcopy;
1786         char *urlp;
1787         char *tptr;
1788 #if ENABLE_FEATURE_HTTPD_CGI
1789         static const char request_HEAD[] ALIGN1 = "HEAD";
1790         const char *prequest;
1791         char *cookie = NULL;
1792         char *content_type = NULL;
1793         unsigned long length = 0;
1794 #elif ENABLE_FEATURE_HTTPD_PROXY
1795 #define prequest request_GET
1796         unsigned long length = 0;
1797 #endif
1798 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1799         smallint authorized = -1;
1800 #endif
1801         smallint ip_allowed;
1802         char http_major_version;
1803 #if ENABLE_FEATURE_HTTPD_PROXY
1804         char http_minor_version;
1805         char *header_buf = header_buf; /* for gcc */
1806         char *header_ptr = header_ptr;
1807         Htaccess_Proxy *proxy_entry;
1808 #endif
1809
1810         /* Allocation of iobuf is postponed until now
1811          * (IOW, server process doesn't need to waste 8k) */
1812         iobuf = xmalloc(IOBUF_SIZE);
1813
1814         rmt_ip = 0;
1815         if (fromAddr->u.sa.sa_family == AF_INET) {
1816                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1817         }
1818 #if ENABLE_FEATURE_IPV6
1819         if (fromAddr->u.sa.sa_family == AF_INET6
1820          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1821          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1822          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1823                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1824 #endif
1825         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1826                 /* NB: can be NULL (user runs httpd -i by hand?) */
1827                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1828         }
1829         if (verbose) {
1830                 /* this trick makes -v logging much simpler */
1831                 if (rmt_ip_str)
1832                         applet_name = rmt_ip_str;
1833                 if (verbose > 2)
1834                         bb_error_msg("connected");
1835         }
1836
1837         /* Install timeout handler */
1838         signal_no_SA_RESTART_empty_mask(SIGALRM, exit_on_signal);
1839         alarm(HEADER_READ_TIMEOUT);
1840
1841         if (!get_line()) /* EOF or error or empty line */
1842                 send_headers_and_exit(HTTP_BAD_REQUEST);
1843
1844         /* Determine type of request (GET/POST) */
1845         urlp = strpbrk(iobuf, " \t");
1846         if (urlp == NULL)
1847                 send_headers_and_exit(HTTP_BAD_REQUEST);
1848         *urlp++ = '\0';
1849 #if ENABLE_FEATURE_HTTPD_CGI
1850         prequest = request_GET;
1851         if (strcasecmp(iobuf, prequest) != 0) {
1852                 prequest = request_HEAD;
1853                 if (strcasecmp(iobuf, prequest) != 0) {
1854                         prequest = "POST";
1855                         if (strcasecmp(iobuf, prequest) != 0)
1856                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1857                 }
1858         }
1859 #else
1860         if (strcasecmp(iobuf, request_GET) != 0)
1861                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1862 #endif
1863         urlp = skip_whitespace(urlp);
1864         if (urlp[0] != '/')
1865                 send_headers_and_exit(HTTP_BAD_REQUEST);
1866
1867         /* Find end of URL and parse HTTP version, if any */
1868         http_major_version = '0';
1869         USE_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1870         tptr = strchrnul(urlp, ' ');
1871         /* Is it " HTTP/"? */
1872         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1873                 http_major_version = tptr[6];
1874                 USE_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1875         }
1876         *tptr = '\0';
1877
1878         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1879         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1880         /*if (urlcopy == NULL)
1881          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1882         strcpy(urlcopy, urlp);
1883         /* NB: urlcopy ptr is never changed after this */
1884
1885         /* Extract url args if present */
1886         g_query = NULL;
1887         tptr = strchr(urlcopy, '?');
1888         if (tptr) {
1889                 *tptr++ = '\0';
1890                 g_query = tptr;
1891         }
1892
1893         /* Decode URL escape sequences */
1894         tptr = decodeString(urlcopy, 0);
1895         if (tptr == NULL)
1896                 send_headers_and_exit(HTTP_BAD_REQUEST);
1897         if (tptr == urlcopy + 1) {
1898                 /* '/' or NUL is encoded */
1899                 send_headers_and_exit(HTTP_NOT_FOUND);
1900         }
1901
1902         /* Canonicalize path */
1903         /* Algorithm stolen from libbb bb_simplify_path(),
1904          * but don't strdup, retain trailing slash, protect root */
1905         urlp = tptr = urlcopy;
1906         do {
1907                 if (*urlp == '/') {
1908                         /* skip duplicate (or initial) slash */
1909                         if (*tptr == '/') {
1910                                 continue;
1911                         }
1912                         if (*tptr == '.') {
1913                                 /* skip extra "/./" */
1914                                 if (tptr[1] == '/' || !tptr[1]) {
1915                                         continue;
1916                                 }
1917                                 /* "..": be careful */
1918                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1919                                         ++tptr;
1920                                         if (urlp == urlcopy) /* protect root */
1921                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1922                                         while (*--urlp != '/') /* omit previous dir */;
1923                                                 continue;
1924                                 }
1925                         }
1926                 }
1927                 *++urlp = *tptr;
1928         } while (*++tptr);
1929         *++urlp = '\0';       /* terminate after last character */
1930
1931         /* If URL is a directory, add '/' */
1932         if (urlp[-1] != '/') {
1933                 if (is_directory(urlcopy + 1, 1, &sb)) {
1934                         found_moved_temporarily = urlcopy;
1935                 }
1936         }
1937
1938         /* Log it */
1939         if (verbose > 1)
1940                 bb_error_msg("url:%s", urlcopy);
1941
1942         tptr = urlcopy;
1943         ip_allowed = checkPermIP();
1944         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1945                 /* have path1/path2 */
1946                 *tptr = '\0';
1947                 if (is_directory(urlcopy + 1, 1, &sb)) {
1948                         /* may have subdir config */
1949                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1950                         ip_allowed = checkPermIP();
1951                 }
1952                 *tptr = '/';
1953         }
1954
1955 #if ENABLE_FEATURE_HTTPD_PROXY
1956         proxy_entry = find_proxy_entry(urlcopy);
1957         if (proxy_entry)
1958                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1959 #endif
1960
1961         if (http_major_version >= '0') {
1962                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1963
1964                 /* Read until blank line for HTTP version specified, else parse immediate */
1965                 while (1) {
1966                         alarm(HEADER_READ_TIMEOUT);
1967                         if (!get_line())
1968                                 break; /* EOF or error or empty line */
1969                         if (DEBUG)
1970                                 bb_error_msg("header: '%s'", iobuf);
1971
1972 #if ENABLE_FEATURE_HTTPD_PROXY
1973                         /* We need 2 more bytes for yet another "\r\n" -
1974                          * see near fdprintf(proxy_fd...) further below */
1975                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1976                                 int len = strlen(iobuf);
1977                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1978                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1979                                 memcpy(header_ptr, iobuf, len);
1980                                 header_ptr += len;
1981                                 header_ptr[0] = '\r';
1982                                 header_ptr[1] = '\n';
1983                                 header_ptr += 2;
1984                         }
1985 #endif
1986
1987 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1988                         /* Try and do our best to parse more lines */
1989                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1990                                 /* extra read only for POST */
1991                                 if (prequest != request_GET
1992 #if ENABLE_FEATURE_HTTPD_CGI
1993                                  && prequest != request_HEAD
1994 #endif
1995                                 ) {
1996                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1997                                         if (!tptr[0])
1998                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1999                                         /* not using strtoul: it ignores leading minus! */
2000                                         length = bb_strtou(tptr, NULL, 10);
2001                                         /* length is "ulong", but we need to pass it to int later */
2002                                         if (errno || length > INT_MAX)
2003                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
2004                                 }
2005                         }
2006 #endif
2007 #if ENABLE_FEATURE_HTTPD_CGI
2008                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
2009                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
2010                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
2011                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
2012                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
2013                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
2014                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2015                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2016                         } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
2017                                 http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
2018                         } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
2019                                 http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
2020                         }
2021 #endif
2022 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2023                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2024                                 /* We only allow Basic credentials.
2025                                  * It shows up as "Authorization: Basic <user>:<passwd>" where
2026                                  * "<user>:<passwd>" is base64 encoded.
2027                                  */
2028                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2029                                 if (STRNCASECMP(tptr, "Basic") != 0)
2030                                         continue;
2031                                 tptr += sizeof("Basic")-1;
2032                                 /* decodeBase64() skips whitespace itself */
2033                                 decodeBase64(tptr);
2034                                 authorized = check_user_passwd(urlcopy, tptr);
2035                         }
2036 #endif
2037 #if ENABLE_FEATURE_HTTPD_RANGES
2038                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2039                                 /* We know only bytes=NNN-[MMM] */
2040                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2041                                 if (strncmp(s, "bytes=", 6) == 0) {
2042                                         s += sizeof("bytes=")-1;
2043                                         range_start = BB_STRTOOFF(s, &s, 10);
2044                                         if (s[0] != '-' || range_start < 0) {
2045                                                 range_start = 0;
2046                                         } else if (s[1]) {
2047                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2048                                                 if (errno || range_end < range_start)
2049                                                         range_start = 0;
2050                                         }
2051                                 }
2052                         }
2053 #endif
2054                 } /* while extra header reading */
2055         }
2056
2057         /* We are done reading headers, disable peer timeout */
2058         alarm(0);
2059
2060         if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || !ip_allowed) {
2061                 /* protect listing [/path]/httpd_conf or IP deny */
2062                 send_headers_and_exit(HTTP_FORBIDDEN);
2063         }
2064
2065 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2066         /* Case: no "Authorization:" was seen, but page does require passwd.
2067          * Check that with dummy user:pass */
2068         if (authorized < 0)
2069                 authorized = check_user_passwd(urlcopy, ":");
2070         if (!authorized)
2071                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2072 #endif
2073
2074         if (found_moved_temporarily) {
2075                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2076         }
2077
2078 #if ENABLE_FEATURE_HTTPD_PROXY
2079         if (proxy_entry != NULL) {
2080                 int proxy_fd;
2081                 len_and_sockaddr *lsa;
2082
2083                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2084                 if (proxy_fd < 0)
2085                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2086                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2087                 if (lsa == NULL)
2088                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2089                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2090                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2091                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2092                                 prequest, /* GET or POST */
2093                                 proxy_entry->url_to, /* url part 1 */
2094                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2095                                 (g_query ? "?" : ""), /* "?" (maybe) */
2096                                 (g_query ? g_query : ""), /* query string (maybe) */
2097                                 http_major_version, http_minor_version);
2098                 header_ptr[0] = '\r';
2099                 header_ptr[1] = '\n';
2100                 header_ptr += 2;
2101                 write(proxy_fd, header_buf, header_ptr - header_buf);
2102                 free(header_buf); /* on the order of 8k, free it */
2103                 /* cgi_io_loop_and_exit needs to have two disctinct fds */
2104                 cgi_io_loop_and_exit(proxy_fd, dup(proxy_fd), length);
2105         }
2106 #endif
2107
2108         tptr = urlcopy + 1;      /* skip first '/' */
2109
2110 #if ENABLE_FEATURE_HTTPD_CGI
2111         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2112                 if (tptr[8] == '\0') {
2113                         /* protect listing "cgi-bin/" */
2114                         send_headers_and_exit(HTTP_FORBIDDEN);
2115                 }
2116                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2117         }
2118 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2119         {
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         }
2130 #endif
2131         if (prequest != request_GET && prequest != request_HEAD) {
2132                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2133         }
2134 #endif  /* FEATURE_HTTPD_CGI */
2135
2136         if (urlp[-1] == '/')
2137                 strcpy(urlp, index_page);
2138         if (stat(tptr, &sb) == 0) {
2139                 file_size = sb.st_size;
2140                 last_mod = sb.st_mtime;
2141         }
2142 #if ENABLE_FEATURE_HTTPD_CGI
2143         else if (urlp[-1] == '/') {
2144                 /* It's a dir URL and there is no index.html
2145                  * Try cgi-bin/index.cgi */
2146                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2147                         urlp[0] = '\0';
2148                         g_query = urlcopy;
2149                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2150                 }
2151         }
2152 #endif
2153         /* else {
2154          *      fall through to send_file, it errors out if open fails
2155          * }
2156          */
2157
2158         send_file_and_exit(tptr,
2159 #if ENABLE_FEATURE_HTTPD_CGI
2160                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2161 #else
2162                 SEND_HEADERS_AND_BODY
2163 #endif
2164         );
2165 }
2166
2167 /*
2168  * The main http server function.
2169  * Given a socket, listen for new connections and farm out
2170  * the processing as a [v]forked process.
2171  * Never returns.
2172  */
2173 #if BB_MMU
2174 static void mini_httpd(int server_socket) NORETURN;
2175 static void mini_httpd(int server_socket)
2176 {
2177         /* NB: it's best to not use xfuncs in this loop before fork().
2178          * Otherwise server may die on transient errors (temporary
2179          * out-of-memory condition, etc), which is Bad(tm).
2180          * Try to do any dangerous calls after fork.
2181          */
2182         while (1) {
2183                 int n;
2184                 len_and_sockaddr fromAddr;
2185
2186                 /* Wait for connections... */
2187                 fromAddr.len = LSA_SIZEOF_SA;
2188                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2189
2190                 if (n < 0)
2191                         continue;
2192                 /* set the KEEPALIVE option to cull dead connections */
2193                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2194
2195                 if (fork() == 0) {
2196                         /* child */
2197 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2198                         /* Do not reload config on HUP */
2199                         signal(SIGHUP, SIG_IGN);
2200 #endif
2201                         close(server_socket);
2202                         xmove_fd(n, 0);
2203                         xdup2(0, 1);
2204
2205                         handle_incoming_and_exit(&fromAddr);
2206                 }
2207                 /* parent, or fork failed */
2208                 close(n);
2209         } /* while (1) */
2210         /* never reached */
2211 }
2212 #else
2213 static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
2214 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2215 {
2216         char *argv_copy[argc + 2];
2217
2218         argv_copy[0] = argv[0];
2219         argv_copy[1] = (char*)"-i";
2220         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2221
2222         /* NB: it's best to not use xfuncs in this loop before vfork().
2223          * Otherwise server may die on transient errors (temporary
2224          * out-of-memory condition, etc), which is Bad(tm).
2225          * Try to do any dangerous calls after fork.
2226          */
2227         while (1) {
2228                 int n;
2229                 len_and_sockaddr fromAddr;
2230
2231                 /* Wait for connections... */
2232                 fromAddr.len = LSA_SIZEOF_SA;
2233                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2234
2235                 if (n < 0)
2236                         continue;
2237                 /* set the KEEPALIVE option to cull dead connections */
2238                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2239
2240                 if (vfork() == 0) {
2241                         /* child */
2242 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2243                         /* Do not reload config on HUP */
2244                         signal(SIGHUP, SIG_IGN);
2245 #endif
2246                         close(server_socket);
2247                         xmove_fd(n, 0);
2248                         xdup2(0, 1);
2249
2250                         /* Run a copy of ourself in inetd mode */
2251                         re_exec(argv_copy);
2252                 }
2253                 /* parent, or vfork failed */
2254                 close(n);
2255         } /* while (1) */
2256         /* never reached */
2257 }
2258 #endif
2259
2260 /*
2261  * Process a HTTP connection on stdin/out.
2262  * Never returns.
2263  */
2264 static void mini_httpd_inetd(void) NORETURN;
2265 static void mini_httpd_inetd(void)
2266 {
2267         len_and_sockaddr fromAddr;
2268
2269         memset(&fromAddr, 0, sizeof(fromAddr));
2270         fromAddr.len = LSA_SIZEOF_SA;
2271         /* NB: can fail if user runs it by hand and types in http cmds */
2272         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2273         handle_incoming_and_exit(&fromAddr);
2274 }
2275
2276 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2277 static void sighup_handler(int sig)
2278 {
2279         parse_conf(default_path_httpd_conf, sig ? SIGNALED_PARSE : FIRST_PARSE);
2280         signal_SA_RESTART_empty_mask(SIGHUP, sighup_handler);
2281 }
2282 #endif
2283
2284 enum {
2285         c_opt_config_file = 0,
2286         d_opt_decode_url,
2287         h_opt_home_httpd,
2288         USE_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2289         USE_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2290         USE_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2291         USE_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2292         p_opt_port      ,
2293         p_opt_inetd     ,
2294         p_opt_foreground,
2295         p_opt_verbose   ,
2296         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2297         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2298         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2299         OPT_ENCODE_URL  = USE_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2300         OPT_REALM       = USE_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2301         OPT_MD5         = USE_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2302         OPT_SETUID      = USE_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2303         OPT_PORT        = 1 << p_opt_port,
2304         OPT_INETD       = 1 << p_opt_inetd,
2305         OPT_FOREGROUND  = 1 << p_opt_foreground,
2306         OPT_VERBOSE     = 1 << p_opt_verbose,
2307 };
2308
2309
2310 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2311 int httpd_main(int argc UNUSED_PARAM, char **argv)
2312 {
2313         int server_socket = server_socket; /* for gcc */
2314         unsigned opt;
2315         char *url_for_decode;
2316         USE_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2317         USE_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2318         USE_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2319         USE_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2320
2321         INIT_G();
2322
2323 #if ENABLE_LOCALE_SUPPORT
2324         /* Undo busybox.c: we want to speak English in http (dates etc) */
2325         setlocale(LC_TIME, "C");
2326 #endif
2327
2328         home_httpd = xrealloc_getcwd_or_warn(NULL);
2329         /* -v counts, -i implies -f */
2330         opt_complementary = "vv:if";
2331         /* We do not "absolutize" path given by -h (home) opt.
2332          * If user gives relative path in -h,
2333          * $SCRIPT_FILENAME will not be set. */
2334         opt = getopt32(argv, "c:d:h:"
2335                         USE_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2336                         USE_FEATURE_HTTPD_BASIC_AUTH("r:")
2337                         USE_FEATURE_HTTPD_AUTH_MD5("m:")
2338                         USE_FEATURE_HTTPD_SETUID("u:")
2339                         "p:ifv",
2340                         &configFile, &url_for_decode, &home_httpd
2341                         USE_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2342                         USE_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2343                         USE_FEATURE_HTTPD_AUTH_MD5(, &pass)
2344                         USE_FEATURE_HTTPD_SETUID(, &s_ugid)
2345                         , &bind_addr_or_port
2346                         , &verbose
2347                 );
2348         if (opt & OPT_DECODE_URL) {
2349                 fputs(decodeString(url_for_decode, 1), stdout);
2350                 return 0;
2351         }
2352 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2353         if (opt & OPT_ENCODE_URL) {
2354                 fputs(encodeString(url_for_encode), stdout);
2355                 return 0;
2356         }
2357 #endif
2358 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2359         if (opt & OPT_MD5) {
2360                 puts(pw_encrypt(pass, "$1$", 1));
2361                 return 0;
2362         }
2363 #endif
2364 #if ENABLE_FEATURE_HTTPD_SETUID
2365         if (opt & OPT_SETUID) {
2366                 xget_uidgid(&ugid, s_ugid);
2367         }
2368 #endif
2369
2370 #if !BB_MMU
2371         if (!(opt & OPT_FOREGROUND)) {
2372                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2373         }
2374 #endif
2375
2376         xchdir(home_httpd);
2377         if (!(opt & OPT_INETD)) {
2378                 signal(SIGCHLD, SIG_IGN);
2379                 server_socket = openServer();
2380 #if ENABLE_FEATURE_HTTPD_SETUID
2381                 /* drop privileges */
2382                 if (opt & OPT_SETUID) {
2383                         if (ugid.gid != (gid_t)-1) {
2384                                 if (setgroups(1, &ugid.gid) == -1)
2385                                         bb_perror_msg_and_die("setgroups");
2386                                 xsetgid(ugid.gid);
2387                         }
2388                         xsetuid(ugid.uid);
2389                 }
2390 #endif
2391         }
2392
2393 #if 0 /*was #if ENABLE_FEATURE_HTTPD_CGI*/
2394         /* User can do it himself: 'env - PATH="$PATH" httpd'
2395          * We don't do it because we don't want to screw users
2396          * which want to do
2397          * 'env - VAR1=val1 VAR2=val2 httpd'
2398          * and have VAR1 and VAR2 values visible in their CGIs.
2399          * Besides, it is also smaller. */
2400         {
2401                 char *p = getenv("PATH");
2402                 /* env strings themself are not freed, no need to xstrdup(p): */
2403                 clearenv();
2404                 if (p)
2405                         putenv(p - 5);
2406 //              if (!(opt & OPT_INETD))
2407 //                      setenv_long("SERVER_PORT", ???);
2408         }
2409 #endif
2410
2411 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2412         if (!(opt & OPT_INETD)) {
2413                 /* runs parse_conf() inside */
2414                 sighup_handler(0);
2415         } else
2416 #endif
2417         {
2418                 parse_conf(default_path_httpd_conf, FIRST_PARSE);
2419         }
2420
2421         xfunc_error_retval = 0;
2422         if (opt & OPT_INETD)
2423                 mini_httpd_inetd();
2424 #if BB_MMU
2425         if (!(opt & OPT_FOREGROUND))
2426                 bb_daemonize(0); /* don't change current directory */
2427         mini_httpd(server_socket); /* never returns */
2428 #else
2429         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2430 #endif
2431         /* return 0; */
2432 }