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 an 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 an 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 an 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   # run xxx.php 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  /* TODO: use TCP_CORK, parse_config() */
  98
  99 #include "libbb.h"
 100 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
 101 # include <sys/sendfile.h>
 102 #endif
 103
 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 static const char index_html[] ALIGN1 = "index.html";
 235
 236
 237 struct globals {
 238         int verbose;            /* must be int (used by getopt32) */
 239         smallint flg_deny_all;
 240
 241         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
 242         time_t last_mod;
 243         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
 244         const char *bind_addr_or_port;
 245
 246         const char *g_query;
 247         const char *opt_c_configFile;
 248         const char *home_httpd;
 249         const char *index_page;
 250
 251         const char *found_mime_type;
 252         const char *found_moved_temporarily;
 253         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 254
 255         IF_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
 256         IF_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
 257         IF_FEATURE_HTTPD_CGI(char *referer;)
 258         IF_FEATURE_HTTPD_CGI(char *user_agent;)
 259         IF_FEATURE_HTTPD_CGI(char *host;)
 260         IF_FEATURE_HTTPD_CGI(char *http_accept;)
 261         IF_FEATURE_HTTPD_CGI(char *http_accept_language;)
 262
 263         off_t file_size;        /* -1 - unknown */
 264 #if ENABLE_FEATURE_HTTPD_RANGES
 265         off_t range_start;
 266         off_t range_end;
 267         off_t range_len;
 268 #endif
 269
 270 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 271         Htaccess *g_auth;       /* config user:password lines */
 272 #endif
 273         Htaccess *mime_a;       /* config mime types */
 274 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 275         Htaccess *script_i;     /* config script interpreters */
 276 #endif
 277         char *iobuf;            /* [IOBUF_SIZE] */
 278 #define hdr_buf bb_common_bufsiz1
 279         char *hdr_ptr;
 280         int hdr_cnt;
 281 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 282         const char *http_error_page[ARRAY_SIZE(http_response_type)];
 283 #endif
 284 #if ENABLE_FEATURE_HTTPD_PROXY
 285         Htaccess_Proxy *proxy;
 286 #endif
 287 };
 288 #define G (*ptr_to_globals)
 289 #define verbose           (G.verbose          )
 290 #define flg_deny_all      (G.flg_deny_all     )
 291 #define rmt_ip            (G.rmt_ip           )
 292 #define bind_addr_or_port (G.bind_addr_or_port)
 293 #define g_query           (G.g_query          )
 294 #define opt_c_configFile  (G.opt_c_configFile )
 295 #define home_httpd        (G.home_httpd       )
 296 #define index_page        (G.index_page       )
 297 #define found_mime_type   (G.found_mime_type  )
 298 #define found_moved_temporarily (G.found_moved_temporarily)
 299 #define last_mod          (G.last_mod         )
 300 #define ip_a_d            (G.ip_a_d           )
 301 #define g_realm           (G.g_realm          )
 302 #define remoteuser        (G.remoteuser       )
 303 #define referer           (G.referer          )
 304 #define user_agent        (G.user_agent       )
 305 #define host              (G.host             )
 306 #define http_accept       (G.http_accept      )
 307 #define http_accept_language (G.http_accept_language)
 308 #define file_size         (G.file_size        )
 309 #if ENABLE_FEATURE_HTTPD_RANGES
 310 #define range_start       (G.range_start      )
 311 #define range_end         (G.range_end        )
 312 #define range_len         (G.range_len        )
 313 #else
 314 enum {
 315         range_start = 0,
 316         range_end = MAXINT(off_t) - 1,
 317         range_len = MAXINT(off_t),
 318 };
 319 #endif
 320 #define rmt_ip_str        (G.rmt_ip_str       )
 321 #define g_auth            (G.g_auth           )
 322 #define mime_a            (G.mime_a           )
 323 #define script_i          (G.script_i         )
 324 #define iobuf             (G.iobuf            )
 325 #define hdr_ptr           (G.hdr_ptr          )
 326 #define hdr_cnt           (G.hdr_cnt          )
 327 #define http_error_page   (G.http_error_page  )
 328 #define proxy             (G.proxy            )
 329 #define INIT_G() do { \
 330         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 331         IF_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
 332         bind_addr_or_port = "80"; \
 333         index_page = index_html; \
 334         file_size = -1; \
 335 } while (0)
 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 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 360 {
 361         free_llist((has_next_ptr**)pptr);
 362 }
 363
 364 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 365 {
 366         free_llist((has_next_ptr**)pptr);
 367 }
 368
 369 /* Returns presumed mask width in bits or < 0 on error.
 370  * Updates strp, stores IP at provided pointer */
 371 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 372 {
 373         const char *p = *strp;
 374         int auto_mask = 8;
 375         unsigned ip = 0;
 376         int j;
 377
 378         if (*p == '/')
 379                 return -auto_mask;
 380
 381         for (j = 0; j < 4; j++) {
 382                 unsigned octet;
 383
 384                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
 385                         return -auto_mask;
 386                 octet = 0;
 387                 while (*p >= '0' && *p <= '9') {
 388                         octet *= 10;
 389                         octet += *p - '0';
 390                         if (octet > 255)
 391                                 return -auto_mask;
 392                         p++;
 393                 }
 394                 if (*p == '.')
 395                         p++;
 396                 if (*p != '/' && *p)
 397                         auto_mask += 8;
 398                 ip = (ip << 8) | octet;
 399         }
 400         if (*p) {
 401                 if (*p != endc)
 402                         return -auto_mask;
 403                 p++;
 404                 if (*p == '\0')
 405                         return -auto_mask;
 406         }
 407         *ipp = ip;
 408         *strp = p;
 409         return auto_mask;
 410 }
 411
 412 /* Returns 0 on success. Stores IP and mask at provided pointers */
 413 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 414 {
 415         int i;
 416         unsigned mask;
 417         char *p;
 418
 419         i = scan_ip(&str, ipp, '/');
 420         if (i < 0)
 421                 return i;
 422
 423         if (*str) {
 424                 /* there is /xxx after dotted-IP address */
 425                 i = bb_strtou(str, &p, 10);
 426                 if (*p == '.') {
 427                         /* 'xxx' itself is dotted-IP mask, parse it */
 428                         /* (return 0 (success) only if it has N.N.N.N form) */
 429                         return scan_ip(&str, maskp, '\0') - 32;
 430                 }
 431                 if (*p)
 432                         return -1;
 433         }
 434
 435         if (i > 32)
 436                 return -1;
 437
 438         if (sizeof(unsigned) == 4 && i == 32) {
 439                 /* mask >>= 32 below may not work */
 440                 mask = 0;
 441         } else {
 442                 mask = 0xffffffff;
 443                 mask >>= i;
 444         }
 445         /* i == 0 -> *maskp = 0x00000000
 446          * i == 1 -> *maskp = 0x80000000
 447          * i == 4 -> *maskp = 0xf0000000
 448          * i == 31 -> *maskp = 0xfffffffe
 449          * i == 32 -> *maskp = 0xffffffff */
 450         *maskp = (uint32_t)(~mask);
 451         return 0;
 452 }
 453
 454 /*
 455  * Parse configuration file into in-memory linked list.
 456  *
 457  * Any previous IP rules are discarded.
 458  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
 459  * are also discarded.  That is, previous settings are retained if flag is
 460  * SUBDIR_PARSE.
 461  * Error pages are only parsed on the main config file.
 462  *
 463  * path   Path where to look for httpd.conf (without filename).
 464  * flag   Type of the parse request.
 465  */
 466 /* flag param: */
 467 enum {
 468         FIRST_PARSE    = 0, /* path will be "/etc" */
 469         SIGNALED_PARSE = 1, /* path will be "/etc" */
 470         SUBDIR_PARSE   = 2, /* path will be derived from URL */
 471 };
 472 static void parse_conf(const char *path, int flag)
 473 {
 474         /* internally used extra flag state */
 475         enum { TRY_CURDIR_PARSE = 3 };
 476
 477         FILE *f;
 478         const char *filename;
 479         char buf[160];
 480
 481         /* discard old rules */
 482         free_Htaccess_IP_list(&ip_a_d);
 483         flg_deny_all = 0;
 484         /* retain previous auth and mime config only for subdir parse */
 485         if (flag != SUBDIR_PARSE) {
 486                 free_Htaccess_list(&mime_a);
 487 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 488                 free_Htaccess_list(&g_auth);
 489 #endif
 490 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 491                 free_Htaccess_list(&script_i);
 492 #endif
 493         }
 494
 495         filename = opt_c_configFile;
 496         if (flag == SUBDIR_PARSE || filename == NULL) {
 497                 filename = alloca(strlen(path) + sizeof(HTTPD_CONF) + 2);
 498                 sprintf((char *)filename, "%s/%s", path, HTTPD_CONF);
 499         }
 500
 501         while ((f = fopen_for_read(filename)) == NULL) {
 502                 if (flag >= SUBDIR_PARSE) { /* SUBDIR or TRY_CURDIR */
 503                         /* config file not found, no changes to config */
 504                         return;
 505                 }
 506                 if (flag == FIRST_PARSE) {
 507                         /* -c CONFFILE given, but CONFFILE doesn't exist? */
 508                         if (opt_c_configFile)
 509                                 bb_simple_perror_msg_and_die(opt_c_configFile);
 510                         /* else: no -c, thus we looked at /etc/httpd.conf,
 511                          * and it's not there. try ./httpd.conf: */
 512                 }
 513                 flag = TRY_CURDIR_PARSE;
 514                 filename = HTTPD_CONF;
 515         }
 516
 517 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 518         /* in "/file:user:pass" lines, we prepend path in subdirs */
 519         if (flag != SUBDIR_PARSE)
 520                 path = "";
 521 #endif
 522         /* The lines can be:
 523          *
 524          * I:default_index_file
 525          * H:http_home
 526          * [AD]:IP[/mask]   # allow/deny, * for wildcard
 527          * Ennn:error.html  # error page for status nnn
 528          * P:/url:[http://]hostname[:port]/new/path # reverse proxy
 529          * .ext:mime/type   # mime type
 530          * *.php:/path/php  # run xxx.php through an interpreter
 531          * /file:user:pass  # username and password
 532          */
 533         while (fgets(buf, sizeof(buf), f) != NULL) {
 534                 unsigned strlen_buf;
 535                 unsigned char ch;
 536                 char *after_colon;
 537
 538                 { /* remove all whitespace, and # comments */
 539                         char *p, *p0;
 540
 541                         p0 = buf;
 542                         /* skip non-whitespace beginning. Often the whole line
 543                          * is non-whitespace. We want this case to work fast,
 544                          * without needless copying, therefore we don't merge
 545                          * this operation into next while loop. */
 546                         while ((ch = *p0) != '\0' && ch != '\n' && ch != '#'
 547                          && ch != ' ' && ch != '\t'
 548                         ) {
 549                                 p0++;
 550                         }
 551                         p = p0;
 552                         /* if we enter this loop, we have some whitespace.
 553                          * discard it */
 554                         while (ch != '\0' && ch != '\n' && ch != '#') {
 555                                 if (ch != ' ' && ch != '\t') {
 556                                         *p++ = ch;
 557                                 }
 558                                 ch = *++p0;
 559                         }
 560                         *p = '\0';
 561                         strlen_buf = p - buf;
 562                         if (strlen_buf == 0)
 563                                 continue; /* empty line */
 564                 }
 565
 566                 after_colon = strchr(buf, ':');
 567                 /* strange line? */
 568                 if (after_colon == NULL || *++after_colon == '\0')
 569                         goto config_error;
 570
 571                 ch = (buf[0] & ~0x20); /* toupper if it's a letter */
 572
 573                 if (ch == 'I') {
 574                         if (index_page != index_html)
 575                                 free((char*)index_page);
 576                         index_page = xstrdup(after_colon);
 577                         continue;
 578                 }
 579
 580                 /* do not allow jumping around using H in subdir's configs */
 581                 if (flag == FIRST_PARSE && ch == 'H') {
 582                         home_httpd = xstrdup(after_colon);
 583                         xchdir(home_httpd);
 584                         continue;
 585                 }
 586
 587                 if (ch == 'A' || ch == 'D') {
 588                         Htaccess_IP *pip;
 589
 590                         if (*after_colon == '*') {
 591                                 if (ch == 'D') {
 592                                         /* memorize "deny all" */
 593                                         flg_deny_all = 1;
 594                                 }
 595                                 /* skip assumed "A:*", it is a default anyway */
 596                                 continue;
 597                         }
 598                         /* store "allow/deny IP/mask" line */
 599                         pip = xzalloc(sizeof(*pip));
 600                         if (scan_ip_mask(after_colon, &pip->ip, &pip->mask)) {
 601                                 /* IP{/mask} syntax error detected, protect all */
 602                                 ch = 'D';
 603                                 pip->mask = 0;
 604                         }
 605                         pip->allow_deny = ch;
 606                         if (ch == 'D') {
 607                                 /* Deny:from_IP - prepend */
 608                                 pip->next = ip_a_d;
 609                                 ip_a_d = pip;
 610                         } else {
 611                                 /* A:from_IP - append (thus all D's precedes A's) */
 612                                 Htaccess_IP *prev_IP = ip_a_d;
 613                                 if (prev_IP == NULL) {
 614                                         ip_a_d = pip;
 615                                 } else {
 616                                         while (prev_IP->next)
 617                                                 prev_IP = prev_IP->next;
 618                                         prev_IP->next = pip;
 619                                 }
 620                         }
 621                         continue;
 622                 }
 623
 624 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 625                 if (flag == FIRST_PARSE && ch == 'E') {
 626                         unsigned i;
 627                         int status = atoi(buf + 1); /* error status code */
 628
 629                         if (status < HTTP_CONTINUE) {
 630                                 goto config_error;
 631                         }
 632                         /* then error page; find matching status */
 633                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 634                                 if (http_response_type[i] == status) {
 635                                         /* We chdir to home_httpd, thus no need to
 636                                          * concat_path_file(home_httpd, after_colon)
 637                                          * here */
 638                                         http_error_page[i] = xstrdup(after_colon);
 639                                         break;
 640                                 }
 641                         }
 642                         continue;
 643                 }
 644 #endif
 645
 646 #if ENABLE_FEATURE_HTTPD_PROXY
 647                 if (flag == FIRST_PARSE && ch == 'P') {
 648                         /* P:/url:[http://]hostname[:port]/new/path */
 649                         char *url_from, *host_port, *url_to;
 650                         Htaccess_Proxy *proxy_entry;
 651
 652                         url_from = after_colon;
 653                         host_port = strchr(after_colon, ':');
 654                         if (host_port == NULL) {
 655                                 goto config_error;
 656                         }
 657                         *host_port++ = '\0';
 658                         if (strncmp(host_port, "http://", 7) == 0)
 659                                 host_port += 7;
 660                         if (*host_port == '\0') {
 661                                 goto config_error;
 662                         }
 663                         url_to = strchr(host_port, '/');
 664                         if (url_to == NULL) {
 665                                 goto config_error;
 666                         }
 667                         *url_to = '\0';
 668                         proxy_entry = xzalloc(sizeof(*proxy_entry));
 669                         proxy_entry->url_from = xstrdup(url_from);
 670                         proxy_entry->host_port = xstrdup(host_port);
 671                         *url_to = '/';
 672                         proxy_entry->url_to = xstrdup(url_to);
 673                         proxy_entry->next = proxy;
 674                         proxy = proxy_entry;
 675                         continue;
 676                 }
 677 #endif
 678                 /* the rest of directives are non-alphabetic,
 679                  * must avoid using "toupper'ed" ch */
 680                 ch = buf[0];
 681
 682                 if (ch == '.' /* ".ext:mime/type" */
 683 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 684                  || (ch == '*' && buf[1] == '.') /* "*.php:/path/php" */
 685 #endif
 686                 ) {
 687                         char *p;
 688                         Htaccess *cur;
 689
 690                         cur = xzalloc(sizeof(*cur) /* includes space for NUL */ + strlen_buf);
 691                         strcpy(cur->before_colon, buf);
 692                         p = cur->before_colon + (after_colon - buf);
 693                         p[-1] = '\0';
 694                         cur->after_colon = p;
 695                         if (ch == '.') {
 696                                 /* .mime line: prepend to mime_a list */
 697                                 cur->next = mime_a;
 698                                 mime_a = cur;
 699                         }
 700 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 701                         else {
 702                                 /* script interpreter line: prepend to script_i list */
 703                                 cur->next = script_i;
 704                                 script_i = cur;
 705                         }
 706 #endif
 707                         continue;
 708                 }
 709
 710 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 711                 if (ch == '/') { /* "/file:user:pass" */
 712                         char *p;
 713                         Htaccess *cur;
 714                         unsigned file_len;
 715
 716                         /* note: path is "" unless we are in SUBDIR parse,
 717                          * otherwise it does NOT start with "/" */
 718                         cur = xzalloc(sizeof(*cur) /* includes space for NUL */
 719                                 + 1 + strlen(path)
 720                                 + strlen_buf
 721                                 );
 722                         /* form "/path/file" */
 723                         sprintf(cur->before_colon, "/%s%.*s",
 724                                 path,
 725                                 (int) (after_colon - buf - 1), /* includes "/", but not ":" */
 726                                 buf);
 727                         /* canonicalize it */
 728                         p = bb_simplify_abs_path_inplace(cur->before_colon);
 729                         file_len = p - cur->before_colon;
 730                         /* add "user:pass" after NUL */
 731                         strcpy(++p, after_colon);
 732                         cur->after_colon = p;
 733
 734                         /* insert cur into g_auth */
 735                         /* g_auth is sorted by decreased filename length */
 736                         {
 737                                 Htaccess *auth, **authp;
 738
 739                                 authp = &g_auth;
 740                                 while ((auth = *authp) != NULL) {
 741                                         if (file_len >= strlen(auth->before_colon)) {
 742                                                 /* insert cur before auth */
 743                                                 cur->next = auth;
 744                                                 break;
 745                                         }
 746                                         authp = &auth->next;
 747                                 }
 748                                 *authp = cur;
 749                         }
 750                         continue;
 751                 }
 752 #endif /* BASIC_AUTH */
 753
 754                 /* the line is not recognized */
 755  config_error:
 756                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 757          } /* while (fgets) */
 758
 759          fclose(f);
 760 }
 761
 762 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
 763 /*
 764  * Given a string, html-encode special characters.
 765  * This is used for the -e command line option to provide an easy way
 766  * for scripts to encode result data without confusing browsers.  The
 767  * returned string pointer is memory allocated by malloc().
 768  *
 769  * Returns a pointer to the encoded string (malloced).
 770  */
 771 static char *encodeString(const char *string)
 772 {
 773         /* take the simple route and encode everything */
 774         /* could possibly scan once to get length.     */
 775         int len = strlen(string);
 776         char *out = xmalloc(len * 6 + 1);
 777         char *p = out;
 778         char ch;
 779
 780         while ((ch = *string++)) {
 781                 /* very simple check for what to encode */
 782                 if (isalnum(ch))
 783                         *p++ = ch;
 784                 else
 785                         p += sprintf(p, "&#%d;", (unsigned char) ch);
 786         }
 787         *p = '\0';
 788         return out;
 789 }
 790 #endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
 791
 792 /*
 793  * Given a URL encoded string, convert it to plain ascii.
 794  * Since decoding always makes strings smaller, the decode is done in-place.
 795  * Thus, callers should xstrdup() the argument if they do not want the
 796  * argument modified.  The return is the original pointer, allowing this
 797  * function to be easily used as arguments to other functions.
 798  *
 799  * string    The first string to decode.
 800  * option_d  1 if called for httpd -d
 801  *
 802  * Returns a pointer to the decoded string (same as input).
 803  */
 804 static unsigned hex_to_bin(unsigned char c)
 805 {
 806         unsigned v;
 807
 808         v = c - '0';
 809         if (v <= 9)
 810                 return v;
 811         /* c | 0x20: letters to lower case, non-letters
 812          * to (potentially different) non-letters */
 813         v = (unsigned)(c | 0x20) - 'a';
 814         if (v <= 5)
 815                 return v + 10;
 816         return ~0;
 817 }
 818 /* For testing:
 819 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
 820 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 821 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 822 */
 823 static char *decodeString(char *orig, int option_d)
 824 {
 825         /* note that decoded string is always shorter than original */
 826         char *string = orig;
 827         char *ptr = string;
 828         char c;
 829
 830         while ((c = *ptr++) != '\0') {
 831                 unsigned v;
 832
 833                 if (option_d && c == '+') {
 834                         *string++ = ' ';
 835                         continue;
 836                 }
 837                 if (c != '%') {
 838                         *string++ = c;
 839                         continue;
 840                 }
 841                 v = hex_to_bin(ptr[0]);
 842                 if (v > 15) {
 843  bad_hex:
 844                         if (!option_d)
 845                                 return NULL;
 846                         *string++ = '%';
 847                         continue;
 848                 }
 849                 v = (v * 16) | hex_to_bin(ptr[1]);
 850                 if (v > 255)
 851                         goto bad_hex;
 852                 if (!option_d && (v == '/' || v == '\0')) {
 853                         /* caller takes it as indication of invalid
 854                          * (dangerous wrt exploits) chars */
 855                         return orig + 1;
 856                 }
 857                 *string++ = v;
 858                 ptr += 2;
 859         }
 860         *string = '\0';
 861         return orig;
 862 }
 863
 864 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 865 /*
 866  * Decode a base64 data stream as per rfc1521.
 867  * Note that the rfc states that non base64 chars are to be ignored.
 868  * Since the decode always results in a shorter size than the input,
 869  * it is OK to pass the input arg as an output arg.
 870  * Parameter: a pointer to a base64 encoded string.
 871  * Decoded data is stored in-place.
 872  */
 873 static void decodeBase64(char *Data)
 874 {
 875         const unsigned char *in = (const unsigned char *)Data;
 876         /* The decoded size will be at most 3/4 the size of the encoded */
 877         unsigned ch = 0;
 878         int i = 0;
 879
 880         while (*in) {
 881                 int t = *in++;
 882
 883                 if (t >= '0' && t <= '9')
 884                         t = t - '0' + 52;
 885                 else if (t >= 'A' && t <= 'Z')
 886                         t = t - 'A';
 887                 else if (t >= 'a' && t <= 'z')
 888                         t = t - 'a' + 26;
 889                 else if (t == '+')
 890                         t = 62;
 891                 else if (t == '/')
 892                         t = 63;
 893                 else if (t == '=')
 894                         t = 0;
 895                 else
 896                         continue;
 897
 898                 ch = (ch << 6) | t;
 899                 i++;
 900                 if (i == 4) {
 901                         *Data++ = (char) (ch >> 16);
 902                         *Data++ = (char) (ch >> 8);
 903                         *Data++ = (char) ch;
 904                         i = 0;
 905                 }
 906         }
 907         *Data = '\0';
 908 }
 909 #endif
 910
 911 /*
 912  * Create a listen server socket on the designated port.
 913  */
 914 static int openServer(void)
 915 {
 916         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 917         if (!errno && n && n <= 0xffff)
 918                 n = create_and_bind_stream_or_die(NULL, n);
 919         else
 920                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 921         xlisten(n, 9);
 922         return n;
 923 }
 924
 925 /*
 926  * Log the connection closure and exit.
 927  */
 928 static void log_and_exit(void) NORETURN;
 929 static void log_and_exit(void)
 930 {
 931         /* Paranoia. IE said to be buggy. It may send some extra data
 932          * or be confused by us just exiting without SHUT_WR. Oh well. */
 933         shutdown(1, SHUT_WR);
 934         /* Why??
 935         (this also messes up stdin when user runs httpd -i from terminal)
 936         ndelay_on(0);
 937         while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
 938                 continue;
 939         */
 940
 941         if (verbose > 2)
 942                 bb_error_msg("closed");
 943         _exit(xfunc_error_retval);
 944 }
 945
 946 /*
 947  * Create and send HTTP response headers.
 948  * The arguments are combined and sent as one write operation.  Note that
 949  * IE will puke big-time if the headers are not sent in one packet and the
 950  * second packet is delayed for any reason.
 951  * responseNum - the result code to send.
 952  */
 953 static void send_headers(int responseNum)
 954 {
 955         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 956
 957         const char *responseString = "";
 958         const char *infoString = NULL;
 959         const char *mime_type;
 960 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 961         const char *error_page = NULL;
 962 #endif
 963         unsigned i;
 964         time_t timer = time(NULL);
 965         char tmp_str[80];
 966         int len;
 967
 968         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 969                 if (http_response_type[i] == responseNum) {
 970                         responseString = http_response[i].name;
 971                         infoString = http_response[i].info;
 972 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 973                         error_page = http_error_page[i];
 974 #endif
 975                         break;
 976                 }
 977         }
 978         /* error message is HTML */
 979         mime_type = responseNum == HTTP_OK ?
 980                                 found_mime_type : "text/html";
 981
 982         if (verbose)
 983                 bb_error_msg("response:%u", responseNum);
 984
 985         /* emit the current date */
 986         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
 987         len = sprintf(iobuf,
 988                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
 989                         "Date: %s\r\nConnection: close\r\n",
 990                         responseNum, responseString, mime_type, tmp_str);
 991
 992 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 993         if (responseNum == HTTP_UNAUTHORIZED) {
 994                 len += sprintf(iobuf + len,
 995                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
 996                                 g_realm);
 997         }
 998 #endif
 999         if (responseNum == HTTP_MOVED_TEMPORARILY) {
1000                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
1001                                 found_moved_temporarily,
1002                                 (g_query ? "?" : ""),
1003                                 (g_query ? g_query : ""));
1004         }
1005
1006 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1007         if (error_page && access(error_page, R_OK) == 0) {
1008                 strcat(iobuf, "\r\n");
1009                 len += 2;
1010
1011                 if (DEBUG)
1012                         fprintf(stderr, "headers: '%s'\n", iobuf);
1013                 full_write(STDOUT_FILENO, iobuf, len);
1014                 if (DEBUG)
1015                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1016                 return send_file_and_exit(error_page, SEND_BODY);
1017         }
1018 #endif
1019
1020         if (file_size != -1) {    /* file */
1021                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1022 #if ENABLE_FEATURE_HTTPD_RANGES
1023                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1024                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"u-%"OFF_FMT"u/%"OFF_FMT"u\r\n",
1025                                         range_start,
1026                                         range_end,
1027                                         file_size);
1028                         file_size = range_end - range_start + 1;
1029                 }
1030 #endif
1031                 len += sprintf(iobuf + len,
1032 #if ENABLE_FEATURE_HTTPD_RANGES
1033                         "Accept-Ranges: bytes\r\n"
1034 #endif
1035                         "Last-Modified: %s\r\n%s %"OFF_FMT"u\r\n",
1036                                 tmp_str,
1037                                 "Content-length:",
1038                                 file_size
1039                 );
1040         }
1041         iobuf[len++] = '\r';
1042         iobuf[len++] = '\n';
1043         if (infoString) {
1044                 len += sprintf(iobuf + len,
1045                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1046                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1047                                 responseNum, responseString,
1048                                 responseNum, responseString, infoString);
1049         }
1050         if (DEBUG)
1051                 fprintf(stderr, "headers: '%s'\n", iobuf);
1052         if (full_write(STDOUT_FILENO, iobuf, len) != len) {
1053                 if (verbose > 1)
1054                         bb_perror_msg("error");
1055                 log_and_exit();
1056         }
1057 }
1058
1059 static void send_headers_and_exit(int responseNum) NORETURN;
1060 static void send_headers_and_exit(int responseNum)
1061 {
1062         send_headers(responseNum);
1063         log_and_exit();
1064 }
1065
1066 /*
1067  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1068  * '\n' is replaced with NUL.
1069  * Return number of characters read or 0 if nothing is read
1070  * ('\r' and '\n' are not counted).
1071  * Data is returned in iobuf.
1072  */
1073 static int get_line(void)
1074 {
1075         int count = 0;
1076         char c;
1077
1078         alarm(HEADER_READ_TIMEOUT);
1079         while (1) {
1080                 if (hdr_cnt <= 0) {
1081                         hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1082                         if (hdr_cnt <= 0)
1083                                 break;
1084                         hdr_ptr = hdr_buf;
1085                 }
1086                 iobuf[count] = c = *hdr_ptr++;
1087                 hdr_cnt--;
1088
1089                 if (c == '\r')
1090                         continue;
1091                 if (c == '\n') {
1092                         iobuf[count] = '\0';
1093                         break;
1094                 }
1095                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1096                         count++;
1097         }
1098         return count;
1099 }
1100
1101 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1102
1103 /* gcc 4.2.1 fares better with NOINLINE */
1104 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
1105 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1106 {
1107         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1108         struct pollfd pfd[3];
1109         int out_cnt; /* we buffer a bit of initial CGI output */
1110         int count;
1111
1112         /* iobuf is used for CGI -> network data,
1113          * hdr_buf is for network -> CGI data (POSTDATA) */
1114
1115         /* If CGI dies, we still want to correctly finish reading its output
1116          * and send it to the peer. So please no SIGPIPEs! */
1117         signal(SIGPIPE, SIG_IGN);
1118
1119         // We inconsistently handle a case when more POSTDATA from network
1120         // is coming than we expected. We may give *some part* of that
1121         // extra data to CGI.
1122
1123         //if (hdr_cnt > post_len) {
1124         //      /* We got more POSTDATA from network than we expected */
1125         //      hdr_cnt = post_len;
1126         //}
1127         post_len -= hdr_cnt;
1128         /* post_len - number of POST bytes not yet read from network */
1129
1130         /* NB: breaking out of this loop jumps to log_and_exit() */
1131         out_cnt = 0;
1132         while (1) {
1133                 memset(pfd, 0, sizeof(pfd));
1134
1135                 pfd[FROM_CGI].fd = fromCgi_rd;
1136                 pfd[FROM_CGI].events = POLLIN;
1137
1138                 if (toCgi_wr) {
1139                         pfd[TO_CGI].fd = toCgi_wr;
1140                         if (hdr_cnt > 0) {
1141                                 pfd[TO_CGI].events = POLLOUT;
1142                         } else if (post_len > 0) {
1143                                 pfd[0].events = POLLIN;
1144                         } else {
1145                                 /* post_len <= 0 && hdr_cnt <= 0:
1146                                  * no more POST data to CGI,
1147                                  * let CGI see EOF on CGI's stdin */
1148                                 close(toCgi_wr);
1149                                 toCgi_wr = 0;
1150                         }
1151                 }
1152
1153                 /* Now wait on the set of sockets */
1154                 count = safe_poll(pfd, 3, -1);
1155                 if (count <= 0) {
1156 #if 0
1157                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1158                                 /* Weird. CGI didn't exit and no fd's
1159                                  * are ready, yet poll returned?! */
1160                                 continue;
1161                         }
1162                         if (DEBUG && WIFEXITED(status))
1163                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1164                         if (DEBUG && WIFSIGNALED(status))
1165                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1166 #endif
1167                         break;
1168                 }
1169
1170                 if (pfd[TO_CGI].revents) {
1171                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1172                         /* Have data from peer and can write to CGI */
1173                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1174                         /* Doesn't happen, we dont use nonblocking IO here
1175                          *if (count < 0 && errno == EAGAIN) {
1176                          *      ...
1177                          *} else */
1178                         if (count > 0) {
1179                                 hdr_ptr += count;
1180                                 hdr_cnt -= count;
1181                         } else {
1182                                 /* EOF/broken pipe to CGI, stop piping POST data */
1183                                 hdr_cnt = post_len = 0;
1184                         }
1185                 }
1186
1187                 if (pfd[0].revents) {
1188                         /* post_len > 0 && hdr_cnt == 0 here */
1189                         /* We expect data, prev data portion is eaten by CGI
1190                          * and there *is* data to read from the peer
1191                          * (POSTDATA) */
1192                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1193                         //count = safe_read(STDIN_FILENO, hdr_buf, count);
1194                         count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1195                         if (count > 0) {
1196                                 hdr_cnt = count;
1197                                 hdr_ptr = hdr_buf;
1198                                 post_len -= count;
1199                         } else {
1200                                 /* no more POST data can be read */
1201                                 post_len = 0;
1202                         }
1203                 }
1204
1205                 if (pfd[FROM_CGI].revents) {
1206                         /* There is something to read from CGI */
1207                         char *rbuf = iobuf;
1208
1209                         /* Are we still buffering CGI output? */
1210                         if (out_cnt >= 0) {
1211                                 /* HTTP_200[] has single "\r\n" at the end.
1212                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1213                                  * CGI scripts MUST send their own header terminated by
1214                                  * empty line, then data. That's why we have only one
1215                                  * <cr><lf> pair here. We will output "200 OK" line
1216                                  * if needed, but CGI still has to provide blank line
1217                                  * between header and body */
1218
1219                                 /* Must use safe_read, not full_read, because
1220                                  * CGI may output a few first bytes and then wait
1221                                  * for POSTDATA without closing stdout.
1222                                  * With full_read we may wait here forever. */
1223                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1224                                 if (count <= 0) {
1225                                         /* eof (or error) and there was no "HTTP",
1226                                          * so write it, then write received data */
1227                                         if (out_cnt) {
1228                                                 full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
1229                                                 full_write(STDOUT_FILENO, rbuf, out_cnt);
1230                                         }
1231                                         break; /* CGI stdout is closed, exiting */
1232                                 }
1233                                 out_cnt += count;
1234                                 count = 0;
1235                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1236                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1237                                         /* send "HTTP/1.0 " */
1238                                         if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
1239                                                 break;
1240                                         rbuf += 8; /* skip "Status: " */
1241                                         count = out_cnt - 8;
1242                                         out_cnt = -1; /* buffering off */
1243                                 } else if (out_cnt >= 4) {
1244                                         /* Did CGI add "HTTP"? */
1245                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1246                                                 /* there is no "HTTP", do it ourself */
1247                                                 if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1248                                                         break;
1249                                         }
1250                                         /* Commented out:
1251                                         if (!strstr(rbuf, "ontent-")) {
1252                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1253                                         }
1254                                          * Counter-example of valid CGI without Content-type:
1255                                          * echo -en "HTTP/1.0 302 Found\r\n"
1256                                          * echo -en "Location: http://www.busybox.net\r\n"
1257                                          * echo -en "\r\n"
1258                                          */
1259                                         count = out_cnt;
1260                                         out_cnt = -1; /* buffering off */
1261                                 }
1262                         } else {
1263                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1264                                 if (count <= 0)
1265                                         break;  /* eof (or error) */
1266                         }
1267                         if (full_write(STDOUT_FILENO, rbuf, count) != count)
1268                                 break;
1269                         if (DEBUG)
1270                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1271                 } /* if (pfd[FROM_CGI].revents) */
1272         } /* while (1) */
1273         log_and_exit();
1274 }
1275 #endif
1276
1277 #if ENABLE_FEATURE_HTTPD_CGI
1278
1279 static void setenv1(const char *name, const char *value)
1280 {
1281         setenv(name, value ? value : "", 1);
1282 }
1283
1284 /*
1285  * Spawn CGI script, forward CGI's stdin/out <=> network
1286  *
1287  * Environment variables are set up and the script is invoked with pipes
1288  * for stdin/stdout.  If a POST is being done the script is fed the POST
1289  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1290  *
1291  * Parameters:
1292  * const char *url              The requested URL (with leading /).
1293  * int post_len                 Length of the POST body.
1294  * const char *cookie           For set HTTP_COOKIE.
1295  * const char *content_type     For set CONTENT_TYPE.
1296  */
1297 static void send_cgi_and_exit(
1298                 const char *url,
1299                 const char *request,
1300                 int post_len,
1301                 const char *cookie,
1302                 const char *content_type) NORETURN;
1303 static void send_cgi_and_exit(
1304                 const char *url,
1305                 const char *request,
1306                 int post_len,
1307                 const char *cookie,
1308                 const char *content_type)
1309 {
1310         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1311         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1312         char *script;
1313         int pid;
1314
1315         /* Make a copy. NB: caller guarantees:
1316          * url[0] == '/', url[1] != '/' */
1317         url = xstrdup(url);
1318
1319         /*
1320          * We are mucking with environment _first_ and then vfork/exec,
1321          * this allows us to use vfork safely. Parent doesn't care about
1322          * these environment changes anyway.
1323          */
1324
1325         /* Check for [dirs/]script.cgi/PATH_INFO */
1326         script = (char*)url;
1327         while ((script = strchr(script + 1, '/')) != NULL) {
1328                 *script = '\0';
1329                 if (!is_directory(url + 1, 1, NULL)) {
1330                         /* not directory, found script.cgi/PATH_INFO */
1331                         *script = '/';
1332                         break;
1333                 }
1334                 *script = '/'; /* is directory, find next '/' */
1335         }
1336         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1337         setenv1("REQUEST_METHOD", request);
1338         if (g_query) {
1339                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1340         } else {
1341                 setenv1("REQUEST_URI", url);
1342         }
1343         if (script != NULL)
1344                 *script = '\0';         /* cut off /PATH_INFO */
1345
1346         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1347         if (home_httpd[0] == '/') {
1348                 char *fullpath = concat_path_file(home_httpd, url);
1349                 setenv1("SCRIPT_FILENAME", fullpath);
1350         }
1351         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1352         setenv1("SCRIPT_NAME", url);
1353         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1354          * QUERY_STRING: The information which follows the ? in the URL
1355          * which referenced this script. This is the query information.
1356          * It should not be decoded in any fashion. This variable
1357          * should always be set when there is query information,
1358          * regardless of command line decoding. */
1359         /* (Older versions of bbox seem to do some decoding) */
1360         setenv1("QUERY_STRING", g_query);
1361         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1362         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1363         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1364         /* Having _separate_ variables for IP and port defeats
1365          * the purpose of having socket abstraction. Which "port"
1366          * are you using on Unix domain socket?
1367          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1368          * Oh well... */
1369         {
1370                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1371                 char *cp = strrchr(p, ':');
1372                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1373                         cp = NULL;
1374                 if (cp) *cp = '\0'; /* delete :PORT */
1375                 setenv1("REMOTE_ADDR", p);
1376                 if (cp) {
1377                         *cp = ':';
1378 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1379                         setenv1("REMOTE_PORT", cp + 1);
1380 #endif
1381                 }
1382         }
1383         setenv1("HTTP_USER_AGENT", user_agent);
1384         if (http_accept)
1385                 setenv1("HTTP_ACCEPT", http_accept);
1386         if (http_accept_language)
1387                 setenv1("HTTP_ACCEPT_LANGUAGE", http_accept_language);
1388         if (post_len)
1389                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1390         if (cookie)
1391                 setenv1("HTTP_COOKIE", cookie);
1392         if (content_type)
1393                 setenv1("CONTENT_TYPE", content_type);
1394 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1395         if (remoteuser) {
1396                 setenv1("REMOTE_USER", remoteuser);
1397                 putenv((char*)"AUTH_TYPE=Basic");
1398         }
1399 #endif
1400         if (referer)
1401                 setenv1("HTTP_REFERER", referer);
1402         setenv1("HTTP_HOST", host); /* set to "" if NULL */
1403         /* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
1404          * just run "env SERVER_NAME=xyz httpd ..." instead */
1405
1406         xpiped_pair(fromCgi);
1407         xpiped_pair(toCgi);
1408
1409         pid = vfork();
1410         if (pid < 0) {
1411                 /* TODO: log perror? */
1412                 log_and_exit();
1413         }
1414
1415         if (!pid) {
1416                 /* Child process */
1417                 char *argv[3];
1418
1419                 xfunc_error_retval = 242;
1420
1421                 /* NB: close _first_, then move fds! */
1422                 close(toCgi.wr);
1423                 close(fromCgi.rd);
1424                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1425                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1426                 /* User seeing stderr output can be a security problem.
1427                  * If CGI really wants that, it can always do dup itself. */
1428                 /* dup2(1, 2); */
1429
1430                 /* Chdiring to script's dir */
1431                 script = strrchr(url, '/');
1432                 if (script != url) { /* paranoia */
1433                         *script = '\0';
1434                         if (chdir(url + 1) != 0) {
1435                                 bb_perror_msg("chdir %s", url + 1);
1436                                 goto error_execing_cgi;
1437                         }
1438                         // not needed: *script = '/';
1439                 }
1440                 script++;
1441
1442                 /* set argv[0] to name without path */
1443                 argv[0] = script;
1444                 argv[1] = NULL;
1445
1446 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1447                 {
1448                         char *suffix = strrchr(script, '.');
1449
1450                         if (suffix) {
1451                                 Htaccess *cur;
1452                                 for (cur = script_i; cur; cur = cur->next) {
1453                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1454                                                 /* found interpreter name */
1455                                                 argv[0] = cur->after_colon;
1456                                                 argv[1] = script;
1457                                                 argv[2] = NULL;
1458                                                 break;
1459                                         }
1460                                 }
1461                         }
1462                 }
1463 #endif
1464                 /* restore default signal dispositions for CGI process */
1465                 bb_signals(0
1466                         | (1 << SIGCHLD)
1467                         | (1 << SIGPIPE)
1468                         | (1 << SIGHUP)
1469                         , SIG_DFL);
1470
1471                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1472                  * without any dir components and will only match a file
1473                  * in the current directory */
1474                 execv(argv[0], argv);
1475                 if (verbose)
1476                         bb_perror_msg("exec %s", argv[0]);
1477  error_execing_cgi:
1478                 /* send to stdout
1479                  * (we are CGI here, our stdout is pumped to the net) */
1480                 send_headers_and_exit(HTTP_NOT_FOUND);
1481         } /* end child */
1482
1483         /* Parent process */
1484
1485         /* Restore variables possibly changed by child */
1486         xfunc_error_retval = 0;
1487
1488         /* Pump data */
1489         close(fromCgi.wr);
1490         close(toCgi.rd);
1491         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1492 }
1493
1494 #endif          /* FEATURE_HTTPD_CGI */
1495
1496 /*
1497  * Send a file response to a HTTP request, and exit
1498  *
1499  * Parameters:
1500  * const char *url  The requested URL (with leading /).
1501  * what             What to send (headers/body/both).
1502  */
1503 static NOINLINE void send_file_and_exit(const char *url, int what)
1504 {
1505         char *suffix;
1506         int fd;
1507         ssize_t count;
1508
1509         fd = open(url, O_RDONLY);
1510         if (fd < 0) {
1511                 if (DEBUG)
1512                         bb_perror_msg("can't open '%s'", url);
1513                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1514                  * IOW: it is unsafe to call send_headers_and_exit
1515                  * if what is SEND_BODY! Can recurse! */
1516                 if (what != SEND_BODY)
1517                         send_headers_and_exit(HTTP_NOT_FOUND);
1518                 log_and_exit();
1519         }
1520         /* If you want to know about EPIPE below
1521          * (happens if you abort downloads from local httpd): */
1522         signal(SIGPIPE, SIG_IGN);
1523
1524         /* If not found, default is "application/octet-stream" */
1525         found_mime_type = "application/octet-stream";
1526         suffix = strrchr(url, '.');
1527         if (suffix) {
1528                 static const char suffixTable[] ALIGN1 =
1529                         /* Shorter suffix must be first:
1530                          * ".html.htm" will fail for ".htm"
1531                          */
1532                         ".txt.h.c.cc.cpp\0" "text/plain\0"
1533                         /* .htm line must be after .h line */
1534                         ".htm.html\0" "text/html\0"
1535                         ".jpg.jpeg\0" "image/jpeg\0"
1536                         ".gif\0"      "image/gif\0"
1537                         ".png\0"      "image/png\0"
1538                         /* .css line must be after .c line */
1539                         ".css\0"      "text/css\0"
1540                         ".wav\0"      "audio/wav\0"
1541                         ".avi\0"      "video/x-msvideo\0"
1542                         ".qt.mov\0"   "video/quicktime\0"
1543                         ".mpe.mpeg\0" "video/mpeg\0"
1544                         ".mid.midi\0" "audio/midi\0"
1545                         ".mp3\0"      "audio/mpeg\0"
1546 #if 0  /* unpopular */
1547                         ".au\0"       "audio/basic\0"
1548                         ".pac\0"      "application/x-ns-proxy-autoconfig\0"
1549                         ".vrml.wrl\0" "model/vrml\0"
1550 #endif
1551                         /* compiler adds another "\0" here */
1552                 ;
1553                 Htaccess *cur;
1554
1555                 /* Examine built-in table */
1556                 const char *table = suffixTable;
1557                 const char *table_next;
1558                 for (; *table; table = table_next) {
1559                         const char *try_suffix;
1560                         const char *mime_type;
1561                         mime_type  = table + strlen(table) + 1;
1562                         table_next = mime_type + strlen(mime_type) + 1;
1563                         try_suffix = strstr(table, suffix);
1564                         if (!try_suffix)
1565                                 continue;
1566                         try_suffix += strlen(suffix);
1567                         if (*try_suffix == '\0' || *try_suffix == '.') {
1568                                 found_mime_type = mime_type;
1569                                 break;
1570                         }
1571                         /* Example: strstr(table, ".av") != NULL, but it
1572                          * does not match ".avi" after all and we end up here.
1573                          * The table is arranged so that in this case we know
1574                          * that it can't match anything in the following lines,
1575                          * and we stop the search: */
1576                         break;
1577                 }
1578                 /* ...then user's table */
1579                 for (cur = mime_a; cur; cur = cur->next) {
1580                         if (strcmp(cur->before_colon, suffix) == 0) {
1581                                 found_mime_type = cur->after_colon;
1582                                 break;
1583                         }
1584                 }
1585         }
1586
1587         if (DEBUG)
1588                 bb_error_msg("sending file '%s' content-type: %s",
1589                         url, found_mime_type);
1590
1591 #if ENABLE_FEATURE_HTTPD_RANGES
1592         if (what == SEND_BODY)
1593                 range_start = 0; /* err pages and ranges don't mix */
1594         range_len = MAXINT(off_t);
1595         if (range_start) {
1596                 if (!range_end) {
1597                         range_end = file_size - 1;
1598                 }
1599                 if (range_end < range_start
1600                  || lseek(fd, range_start, SEEK_SET) != range_start
1601                 ) {
1602                         lseek(fd, 0, SEEK_SET);
1603                         range_start = 0;
1604                 } else {
1605                         range_len = range_end - range_start + 1;
1606                         send_headers(HTTP_PARTIAL_CONTENT);
1607                         what = SEND_BODY;
1608                 }
1609         }
1610 #endif
1611         if (what & SEND_HEADERS)
1612                 send_headers(HTTP_OK);
1613 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1614         {
1615                 off_t offset = range_start;
1616                 while (1) {
1617                         /* sz is rounded down to 64k */
1618                         ssize_t sz = MAXINT(ssize_t) - 0xffff;
1619                         IF_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1620                         count = sendfile(STDOUT_FILENO, fd, &offset, sz);
1621                         if (count < 0) {
1622                                 if (offset == range_start)
1623                                         break; /* fall back to read/write loop */
1624                                 goto fin;
1625                         }
1626                         IF_FEATURE_HTTPD_RANGES(range_len -= sz;)
1627                         if (count == 0 || range_len == 0)
1628                                 log_and_exit();
1629                 }
1630         }
1631 #endif
1632         while ((count = safe_read(fd, iobuf, IOBUF_SIZE)) > 0) {
1633                 ssize_t n;
1634                 IF_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1635                 n = full_write(STDOUT_FILENO, iobuf, count);
1636                 if (count != n)
1637                         break;
1638                 IF_FEATURE_HTTPD_RANGES(range_len -= count;)
1639                 if (range_len == 0)
1640                         break;
1641         }
1642         if (count < 0) {
1643  IF_FEATURE_HTTPD_USE_SENDFILE(fin:)
1644                 if (verbose > 1)
1645                         bb_perror_msg("error");
1646         }
1647         log_and_exit();
1648 }
1649
1650 static int checkPermIP(void)
1651 {
1652         Htaccess_IP *cur;
1653
1654         for (cur = ip_a_d; cur; cur = cur->next) {
1655 #if DEBUG
1656                 fprintf(stderr,
1657                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1658                         rmt_ip_str,
1659                         (unsigned char)(cur->ip >> 24),
1660                         (unsigned char)(cur->ip >> 16),
1661                         (unsigned char)(cur->ip >> 8),
1662                         (unsigned char)(cur->ip),
1663                         (unsigned char)(cur->mask >> 24),
1664                         (unsigned char)(cur->mask >> 16),
1665                         (unsigned char)(cur->mask >> 8),
1666                         (unsigned char)(cur->mask)
1667                 );
1668 #endif
1669                 if ((rmt_ip & cur->mask) == cur->ip)
1670                         return (cur->allow_deny == 'A'); /* A -> 1 */
1671         }
1672
1673         return !flg_deny_all; /* depends on whether we saw "D:*" */
1674 }
1675
1676 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1677 /*
1678  * Config file entries are of the form "/<path>:<user>:<passwd>".
1679  * If config file has no prefix match for path, access is allowed.
1680  *
1681  * path                 The file path
1682  * user_and_passwd      "user:passwd" to validate
1683  *
1684  * Returns 1 if user_and_passwd is OK.
1685  */
1686 static int check_user_passwd(const char *path, const char *user_and_passwd)
1687 {
1688         Htaccess *cur;
1689         const char *prev = NULL;
1690
1691         for (cur = g_auth; cur; cur = cur->next) {
1692                 const char *dir_prefix;
1693                 size_t len;
1694
1695                 dir_prefix = cur->before_colon;
1696
1697                 /* WHY? */
1698                 /* If already saw a match, don't accept other different matches */
1699                 if (prev && strcmp(prev, dir_prefix) != 0)
1700                         continue;
1701
1702                 if (DEBUG)
1703                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
1704
1705                 /* If it's not a prefix match, continue searching */
1706                 len = strlen(dir_prefix);
1707                 if (len != 1 /* dir_prefix "/" matches all, don't need to check */
1708                  && (strncmp(dir_prefix, path, len) != 0
1709                     || (path[len] != '/' && path[len] != '\0'))
1710                 ) {
1711                         continue;
1712                 }
1713
1714                 /* Path match found */
1715                 prev = dir_prefix;
1716
1717                 if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1718                         char *md5_passwd;
1719
1720                         md5_passwd = strchr(cur->after_colon, ':');
1721                         if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
1722                          && md5_passwd[3] == '$' && md5_passwd[4]
1723                         ) {
1724                                 char *encrypted;
1725                                 int r, user_len_p1;
1726
1727                                 md5_passwd++;
1728                                 user_len_p1 = md5_passwd - cur->after_colon;
1729                                 /* comparing "user:" */
1730                                 if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
1731                                         continue;
1732                                 }
1733
1734                                 encrypted = pw_encrypt(
1735                                         user_and_passwd + user_len_p1 /* cleartext pwd from user */,
1736                                         md5_passwd /*salt */, 1 /* cleanup */);
1737                                 r = strcmp(encrypted, md5_passwd);
1738                                 free(encrypted);
1739                                 if (r == 0)
1740                                         goto set_remoteuser_var; /* Ok */
1741                                 continue;
1742                         }
1743                 }
1744
1745                 /* Comparing plaintext "user:pass" in one go */
1746                 if (strcmp(cur->after_colon, user_and_passwd) == 0) {
1747  set_remoteuser_var:
1748                         remoteuser = xstrndup(user_and_passwd,
1749                                         strchrnul(user_and_passwd, ':') - user_and_passwd);
1750                         return 1; /* Ok */
1751                 }
1752         } /* for */
1753
1754         /* 0(bad) if prev is set: matches were found but passwd was wrong */
1755         return (prev == NULL);
1756 }
1757 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1758
1759 #if ENABLE_FEATURE_HTTPD_PROXY
1760 static Htaccess_Proxy *find_proxy_entry(const char *url)
1761 {
1762         Htaccess_Proxy *p;
1763         for (p = proxy; p; p = p->next) {
1764                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1765                         return p;
1766         }
1767         return NULL;
1768 }
1769 #endif
1770
1771 /*
1772  * Handle timeouts
1773  */
1774 static void send_REQUEST_TIMEOUT_and_exit(int sig) NORETURN;
1775 static void send_REQUEST_TIMEOUT_and_exit(int sig UNUSED_PARAM)
1776 {
1777         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1778 }
1779
1780 /*
1781  * Handle an incoming http request and exit.
1782  */
1783 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
1784 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1785 {
1786         static const char request_GET[] ALIGN1 = "GET";
1787         struct stat sb;
1788         char *urlcopy;
1789         char *urlp;
1790         char *tptr;
1791 #if ENABLE_FEATURE_HTTPD_CGI
1792         static const char request_HEAD[] ALIGN1 = "HEAD";
1793         const char *prequest;
1794         char *cookie = NULL;
1795         char *content_type = NULL;
1796         unsigned long length = 0;
1797 #elif ENABLE_FEATURE_HTTPD_PROXY
1798 #define prequest request_GET
1799         unsigned long length = 0;
1800 #endif
1801 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1802         smallint authorized = -1;
1803 #endif
1804         smallint ip_allowed;
1805         char http_major_version;
1806 #if ENABLE_FEATURE_HTTPD_PROXY
1807         char http_minor_version;
1808         char *header_buf = header_buf; /* for gcc */
1809         char *header_ptr = header_ptr;
1810         Htaccess_Proxy *proxy_entry;
1811 #endif
1812
1813         /* Allocation of iobuf is postponed until now
1814          * (IOW, server process doesn't need to waste 8k) */
1815         iobuf = xmalloc(IOBUF_SIZE);
1816
1817         rmt_ip = 0;
1818         if (fromAddr->u.sa.sa_family == AF_INET) {
1819                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1820         }
1821 #if ENABLE_FEATURE_IPV6
1822         if (fromAddr->u.sa.sa_family == AF_INET6
1823          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1824          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1825          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1826                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1827 #endif
1828         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1829                 /* NB: can be NULL (user runs httpd -i by hand?) */
1830                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1831         }
1832         if (verbose) {
1833                 /* this trick makes -v logging much simpler */
1834                 if (rmt_ip_str)
1835                         applet_name = rmt_ip_str;
1836                 if (verbose > 2)
1837                         bb_error_msg("connected");
1838         }
1839
1840         /* Install timeout handler. get_line() needs it. */
1841         signal(SIGALRM, send_REQUEST_TIMEOUT_and_exit);
1842
1843         if (!get_line()) /* EOF or error or empty line */
1844                 send_headers_and_exit(HTTP_BAD_REQUEST);
1845
1846         /* Determine type of request (GET/POST) */
1847         urlp = strpbrk(iobuf, " \t");
1848         if (urlp == NULL)
1849                 send_headers_and_exit(HTTP_BAD_REQUEST);
1850         *urlp++ = '\0';
1851 #if ENABLE_FEATURE_HTTPD_CGI
1852         prequest = request_GET;
1853         if (strcasecmp(iobuf, prequest) != 0) {
1854                 prequest = request_HEAD;
1855                 if (strcasecmp(iobuf, prequest) != 0) {
1856                         prequest = "POST";
1857                         if (strcasecmp(iobuf, prequest) != 0)
1858                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1859                 }
1860         }
1861 #else
1862         if (strcasecmp(iobuf, request_GET) != 0)
1863                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1864 #endif
1865         urlp = skip_whitespace(urlp);
1866         if (urlp[0] != '/')
1867                 send_headers_and_exit(HTTP_BAD_REQUEST);
1868
1869         /* Find end of URL and parse HTTP version, if any */
1870         http_major_version = '0';
1871         IF_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1872         tptr = strchrnul(urlp, ' ');
1873         /* Is it " HTTP/"? */
1874         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1875                 http_major_version = tptr[6];
1876                 IF_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1877         }
1878         *tptr = '\0';
1879
1880         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1881         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1882         /*if (urlcopy == NULL)
1883          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1884         strcpy(urlcopy, urlp);
1885         /* NB: urlcopy ptr is never changed after this */
1886
1887         /* Extract url args if present */
1888         g_query = NULL;
1889         tptr = strchr(urlcopy, '?');
1890         if (tptr) {
1891                 *tptr++ = '\0';
1892                 g_query = tptr;
1893         }
1894
1895         /* Decode URL escape sequences */
1896         tptr = decodeString(urlcopy, 0);
1897         if (tptr == NULL)
1898                 send_headers_and_exit(HTTP_BAD_REQUEST);
1899         if (tptr == urlcopy + 1) {
1900                 /* '/' or NUL is encoded */
1901                 send_headers_and_exit(HTTP_NOT_FOUND);
1902         }
1903
1904         /* Canonicalize path */
1905         /* Algorithm stolen from libbb bb_simplify_path(),
1906          * but don't strdup, retain trailing slash, protect root */
1907         urlp = tptr = urlcopy;
1908         do {
1909                 if (*urlp == '/') {
1910                         /* skip duplicate (or initial) slash */
1911                         if (*tptr == '/') {
1912                                 continue;
1913                         }
1914                         if (*tptr == '.') {
1915                                 /* skip extra "/./" */
1916                                 if (tptr[1] == '/' || !tptr[1]) {
1917                                         continue;
1918                                 }
1919                                 /* "..": be careful */
1920                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1921                                         ++tptr;
1922                                         if (urlp == urlcopy) /* protect root */
1923                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1924                                         while (*--urlp != '/') /* omit previous dir */;
1925                                                 continue;
1926                                 }
1927                         }
1928                 }
1929                 *++urlp = *tptr;
1930         } while (*++tptr);
1931         *++urlp = '\0';       /* terminate after last character */
1932
1933         /* If URL is a directory, add '/' */
1934         if (urlp[-1] != '/') {
1935                 if (is_directory(urlcopy + 1, 1, NULL)) {
1936                         found_moved_temporarily = urlcopy;
1937                 }
1938         }
1939
1940         /* Log it */
1941         if (verbose > 1)
1942                 bb_error_msg("url:%s", urlcopy);
1943
1944         tptr = urlcopy;
1945         ip_allowed = checkPermIP();
1946         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1947                 /* have path1/path2 */
1948                 *tptr = '\0';
1949                 if (is_directory(urlcopy + 1, 1, NULL)) {
1950                         /* may have subdir config */
1951                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1952                         ip_allowed = checkPermIP();
1953                 }
1954                 *tptr = '/';
1955         }
1956
1957 #if ENABLE_FEATURE_HTTPD_PROXY
1958         proxy_entry = find_proxy_entry(urlcopy);
1959         if (proxy_entry)
1960                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1961 #endif
1962
1963         if (http_major_version >= '0') {
1964                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1965
1966                 /* Read until blank line for HTTP version specified, else parse immediate */
1967                 while (1) {
1968                         if (!get_line())
1969                                 break; /* EOF or error or empty line */
1970                         if (DEBUG)
1971                                 bb_error_msg("header: '%s'", iobuf);
1972
1973 #if ENABLE_FEATURE_HTTPD_PROXY
1974                         /* We need 2 more bytes for yet another "\r\n" -
1975                          * see near fdprintf(proxy_fd...) further below */
1976                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1977                                 int len = strlen(iobuf);
1978                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1979                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1980                                 memcpy(header_ptr, iobuf, len);
1981                                 header_ptr += len;
1982                                 header_ptr[0] = '\r';
1983                                 header_ptr[1] = '\n';
1984                                 header_ptr += 2;
1985                         }
1986 #endif
1987
1988 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1989                         /* Try and do our best to parse more lines */
1990                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1991                                 /* extra read only for POST */
1992                                 if (prequest != request_GET
1993 #if ENABLE_FEATURE_HTTPD_CGI
1994                                  && prequest != request_HEAD
1995 #endif
1996                                 ) {
1997                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1998                                         if (!tptr[0])
1999                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
2000                                         /* not using strtoul: it ignores leading minus! */
2001                                         length = bb_strtou(tptr, NULL, 10);
2002                                         /* length is "ulong", but we need to pass it to int later */
2003                                         if (errno || length > INT_MAX)
2004                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
2005                                 }
2006                         }
2007 #endif
2008 #if ENABLE_FEATURE_HTTPD_CGI
2009                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
2010                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
2011                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
2012                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
2013                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
2014                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
2015                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2016                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2017                         } else if (STRNCASECMP(iobuf, "Host:") == 0) {
2018                                 host = xstrdup(skip_whitespace(iobuf + sizeof("Host:")-1));
2019                         } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
2020                                 http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
2021                         } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
2022                                 http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
2023                         }
2024 #endif
2025 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2026                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2027                                 /* We only allow Basic credentials.
2028                                  * It shows up as "Authorization: Basic <user>:<passwd>" where
2029                                  * "<user>:<passwd>" is base64 encoded.
2030                                  */
2031                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2032                                 if (STRNCASECMP(tptr, "Basic") != 0)
2033                                         continue;
2034                                 tptr += sizeof("Basic")-1;
2035                                 /* decodeBase64() skips whitespace itself */
2036                                 decodeBase64(tptr);
2037                                 authorized = check_user_passwd(urlcopy, tptr);
2038                         }
2039 #endif
2040 #if ENABLE_FEATURE_HTTPD_RANGES
2041                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2042                                 /* We know only bytes=NNN-[MMM] */
2043                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2044                                 if (strncmp(s, "bytes=", 6) == 0) {
2045                                         s += sizeof("bytes=")-1;
2046                                         range_start = BB_STRTOOFF(s, &s, 10);
2047                                         if (s[0] != '-' || range_start < 0) {
2048                                                 range_start = 0;
2049                                         } else if (s[1]) {
2050                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2051                                                 if (errno || range_end < range_start)
2052                                                         range_start = 0;
2053                                         }
2054                                 }
2055                         }
2056 #endif
2057                 } /* while extra header reading */
2058         }
2059
2060         /* We are done reading headers, disable peer timeout */
2061         alarm(0);
2062
2063         if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0 || !ip_allowed) {
2064                 /* protect listing [/path]/httpd.conf or IP deny */
2065                 send_headers_and_exit(HTTP_FORBIDDEN);
2066         }
2067
2068 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2069         /* Case: no "Authorization:" was seen, but page does require passwd.
2070          * Check that with dummy user:pass */
2071         if (authorized < 0)
2072                 authorized = check_user_passwd(urlcopy, ":");
2073         if (!authorized)
2074                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2075 #endif
2076
2077         if (found_moved_temporarily) {
2078                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2079         }
2080
2081 #if ENABLE_FEATURE_HTTPD_PROXY
2082         if (proxy_entry != NULL) {
2083                 int proxy_fd;
2084                 len_and_sockaddr *lsa;
2085
2086                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2087                 if (proxy_fd < 0)
2088                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2089                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2090                 if (lsa == NULL)
2091                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2092                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2093                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2094                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2095                                 prequest, /* GET or POST */
2096                                 proxy_entry->url_to, /* url part 1 */
2097                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2098                                 (g_query ? "?" : ""), /* "?" (maybe) */
2099                                 (g_query ? g_query : ""), /* query string (maybe) */
2100                                 http_major_version, http_minor_version);
2101                 header_ptr[0] = '\r';
2102                 header_ptr[1] = '\n';
2103                 header_ptr += 2;
2104                 write(proxy_fd, header_buf, header_ptr - header_buf);
2105                 free(header_buf); /* on the order of 8k, free it */
2106                 /* cgi_io_loop_and_exit needs to have two distinct fds */
2107                 cgi_io_loop_and_exit(proxy_fd, dup(proxy_fd), length);
2108         }
2109 #endif
2110
2111         tptr = urlcopy + 1;      /* skip first '/' */
2112
2113 #if ENABLE_FEATURE_HTTPD_CGI
2114         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2115                 if (tptr[8] == '\0') {
2116                         /* protect listing "cgi-bin/" */
2117                         send_headers_and_exit(HTTP_FORBIDDEN);
2118                 }
2119                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2120         }
2121 #endif
2122
2123         if (urlp[-1] == '/')
2124                 strcpy(urlp, index_page);
2125         if (stat(tptr, &sb) == 0) {
2126 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2127                 char *suffix = strrchr(tptr, '.');
2128                 if (suffix) {
2129                         Htaccess *cur;
2130                         for (cur = script_i; cur; cur = cur->next) {
2131                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2132                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2133                                 }
2134                         }
2135                 }
2136 #endif
2137                 file_size = sb.st_size;
2138                 last_mod = sb.st_mtime;
2139         }
2140 #if ENABLE_FEATURE_HTTPD_CGI
2141         else if (urlp[-1] == '/') {
2142                 /* It's a dir URL and there is no index.html
2143                  * Try cgi-bin/index.cgi */
2144                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2145                         urlp[0] = '\0';
2146                         g_query = urlcopy;
2147                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2148                 }
2149         }
2150         /* else fall through to send_file, it errors out if open fails: */
2151
2152         if (prequest != request_GET && prequest != request_HEAD) {
2153                 /* POST for files does not make sense */
2154                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2155         }
2156         send_file_and_exit(tptr,
2157                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2158         );
2159 #else
2160         send_file_and_exit(tptr, SEND_HEADERS_AND_BODY);
2161 #endif
2162 }
2163
2164 /*
2165  * The main http server function.
2166  * Given a socket, listen for new connections and farm out
2167  * the processing as a [v]forked process.
2168  * Never returns.
2169  */
2170 #if BB_MMU
2171 static void mini_httpd(int server_socket) NORETURN;
2172 static void mini_httpd(int server_socket)
2173 {
2174         /* NB: it's best to not use xfuncs in this loop before fork().
2175          * Otherwise server may die on transient errors (temporary
2176          * out-of-memory condition, etc), which is Bad(tm).
2177          * Try to do any dangerous calls after fork.
2178          */
2179         while (1) {
2180                 int n;
2181                 len_and_sockaddr fromAddr;
2182
2183                 /* Wait for connections... */
2184                 fromAddr.len = LSA_SIZEOF_SA;
2185                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2186
2187                 if (n < 0)
2188                         continue;
2189                 /* set the KEEPALIVE option to cull dead connections */
2190                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2191
2192                 if (fork() == 0) {
2193                         /* child */
2194                         /* Do not reload config on HUP */
2195                         signal(SIGHUP, SIG_IGN);
2196                         close(server_socket);
2197                         xmove_fd(n, 0);
2198                         xdup2(0, 1);
2199
2200                         handle_incoming_and_exit(&fromAddr);
2201                 }
2202                 /* parent, or fork failed */
2203                 close(n);
2204         } /* while (1) */
2205         /* never reached */
2206 }
2207 #else
2208 static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
2209 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2210 {
2211         char *argv_copy[argc + 2];
2212
2213         argv_copy[0] = argv[0];
2214         argv_copy[1] = (char*)"-i";
2215         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2216
2217         /* NB: it's best to not use xfuncs in this loop before vfork().
2218          * Otherwise server may die on transient errors (temporary
2219          * out-of-memory condition, etc), which is Bad(tm).
2220          * Try to do any dangerous calls after fork.
2221          */
2222         while (1) {
2223                 int n;
2224                 len_and_sockaddr fromAddr;
2225
2226                 /* Wait for connections... */
2227                 fromAddr.len = LSA_SIZEOF_SA;
2228                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2229
2230                 if (n < 0)
2231                         continue;
2232                 /* set the KEEPALIVE option to cull dead connections */
2233                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2234
2235                 if (vfork() == 0) {
2236                         /* child */
2237                         /* Do not reload config on HUP */
2238                         signal(SIGHUP, SIG_IGN);
2239                         close(server_socket);
2240                         xmove_fd(n, 0);
2241                         xdup2(0, 1);
2242
2243                         /* Run a copy of ourself in inetd mode */
2244                         re_exec(argv_copy);
2245                 }
2246                 /* parent, or vfork failed */
2247                 close(n);
2248         } /* while (1) */
2249         /* never reached */
2250 }
2251 #endif
2252
2253 /*
2254  * Process a HTTP connection on stdin/out.
2255  * Never returns.
2256  */
2257 static void mini_httpd_inetd(void) NORETURN;
2258 static void mini_httpd_inetd(void)
2259 {
2260         len_and_sockaddr fromAddr;
2261
2262         memset(&fromAddr, 0, sizeof(fromAddr));
2263         fromAddr.len = LSA_SIZEOF_SA;
2264         /* NB: can fail if user runs it by hand and types in http cmds */
2265         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2266         handle_incoming_and_exit(&fromAddr);
2267 }
2268
2269 static void sighup_handler(int sig UNUSED_PARAM)
2270 {
2271         parse_conf(DEFAULT_PATH_HTTPD_CONF, SIGNALED_PARSE);
2272 }
2273
2274 enum {
2275         c_opt_config_file = 0,
2276         d_opt_decode_url,
2277         h_opt_home_httpd,
2278         IF_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2279         IF_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2280         IF_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2281         IF_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2282         p_opt_port      ,
2283         p_opt_inetd     ,
2284         p_opt_foreground,
2285         p_opt_verbose   ,
2286         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2287         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2288         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2289         OPT_ENCODE_URL  = IF_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2290         OPT_REALM       = IF_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2291         OPT_MD5         = IF_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2292         OPT_SETUID      = IF_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2293         OPT_PORT        = 1 << p_opt_port,
2294         OPT_INETD       = 1 << p_opt_inetd,
2295         OPT_FOREGROUND  = 1 << p_opt_foreground,
2296         OPT_VERBOSE     = 1 << p_opt_verbose,
2297 };
2298
2299
2300 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2301 int httpd_main(int argc UNUSED_PARAM, char **argv)
2302 {
2303         int server_socket = server_socket; /* for gcc */
2304         unsigned opt;
2305         char *url_for_decode;
2306         IF_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2307         IF_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2308         IF_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2309         IF_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2310
2311         INIT_G();
2312
2313 #if ENABLE_LOCALE_SUPPORT
2314         /* Undo busybox.c: we want to speak English in http (dates etc) */
2315         setlocale(LC_TIME, "C");
2316 #endif
2317
2318         home_httpd = xrealloc_getcwd_or_warn(NULL);
2319         /* -v counts, -i implies -f */
2320         opt_complementary = "vv:if";
2321         /* We do not "absolutize" path given by -h (home) opt.
2322          * If user gives relative path in -h,
2323          * $SCRIPT_FILENAME will not be set. */
2324         opt = getopt32(argv, "c:d:h:"
2325                         IF_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2326                         IF_FEATURE_HTTPD_BASIC_AUTH("r:")
2327                         IF_FEATURE_HTTPD_AUTH_MD5("m:")
2328                         IF_FEATURE_HTTPD_SETUID("u:")
2329                         "p:ifv",
2330                         &opt_c_configFile, &url_for_decode, &home_httpd
2331                         IF_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2332                         IF_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2333                         IF_FEATURE_HTTPD_AUTH_MD5(, &pass)
2334                         IF_FEATURE_HTTPD_SETUID(, &s_ugid)
2335                         , &bind_addr_or_port
2336                         , &verbose
2337                 );
2338         if (opt & OPT_DECODE_URL) {
2339                 fputs(decodeString(url_for_decode, 1), stdout);
2340                 return 0;
2341         }
2342 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2343         if (opt & OPT_ENCODE_URL) {
2344                 fputs(encodeString(url_for_encode), stdout);
2345                 return 0;
2346         }
2347 #endif
2348 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2349         if (opt & OPT_MD5) {
2350                 char salt[sizeof("$1$XXXXXXXX")];
2351                 salt[0] = '$';
2352                 salt[1] = '1';
2353                 salt[2] = '$';
2354                 crypt_make_salt(salt + 3, 4, 0);
2355                 puts(pw_encrypt(pass, salt, 1));
2356                 return 0;
2357         }
2358 #endif
2359 #if ENABLE_FEATURE_HTTPD_SETUID
2360         if (opt & OPT_SETUID) {
2361                 xget_uidgid(&ugid, s_ugid);
2362         }
2363 #endif
2364
2365 #if !BB_MMU
2366         if (!(opt & OPT_FOREGROUND)) {
2367                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2368         }
2369 #endif
2370
2371         xchdir(home_httpd);
2372         if (!(opt & OPT_INETD)) {
2373                 signal(SIGCHLD, SIG_IGN);
2374                 server_socket = openServer();
2375 #if ENABLE_FEATURE_HTTPD_SETUID
2376                 /* drop privileges */
2377                 if (opt & OPT_SETUID) {
2378                         if (ugid.gid != (gid_t)-1) {
2379                                 if (setgroups(1, &ugid.gid) == -1)
2380                                         bb_perror_msg_and_die("setgroups");
2381                                 xsetgid(ugid.gid);
2382                         }
2383                         xsetuid(ugid.uid);
2384                 }
2385 #endif
2386         }
2387
2388 #if 0
2389         /* User can do it himself: 'env - PATH="$PATH" httpd'
2390          * We don't do it because we don't want to screw users
2391          * which want to do
2392          * 'env - VAR1=val1 VAR2=val2 httpd'
2393          * and have VAR1 and VAR2 values visible in their CGIs.
2394          * Besides, it is also smaller. */
2395         {
2396                 char *p = getenv("PATH");
2397                 /* env strings themself are not freed, no need to xstrdup(p): */
2398                 clearenv();
2399                 if (p)
2400                         putenv(p - 5);
2401 //              if (!(opt & OPT_INETD))
2402 //                      setenv_long("SERVER_PORT", ???);
2403         }
2404 #endif
2405
2406         parse_conf(DEFAULT_PATH_HTTPD_CONF, FIRST_PARSE);
2407         if (!(opt & OPT_INETD))
2408                 signal(SIGHUP, sighup_handler);
2409
2410         xfunc_error_retval = 0;
2411         if (opt & OPT_INETD)
2412                 mini_httpd_inetd();
2413 #if BB_MMU
2414         if (!(opt & OPT_FOREGROUND))
2415                 bb_daemonize(0); /* don't change current directory */
2416         mini_httpd(server_socket); /* never returns */
2417 #else
2418         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2419 #endif
2420         /* return 0; */
2421 }