networking/httpd.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * httpd implementation for busybox
   4  *
   5  * Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
   6  * Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   9  *
  10  *****************************************************************************
  11  *
  12  * Typical usage:
  13  * For non root user:
  14  *      httpd -p 8080 -h $HOME/public_html
  15  * For daemon start from rc script with uid=0:
  16  *      httpd -u www
  17  * which is equivalent to (assuming user www has uid 80):
  18  *      httpd -p 80 -u 80 -h $PWD -c /etc/httpd.conf -r "Web Server Authentication"
  19  *
  20  * When an url starts with "/cgi-bin/" it is assumed to be a cgi script.
  21  * The server changes directory to the location of the script and executes it
  22  * after setting QUERY_STRING and other environment variables.
  23  *
  24  * If directory URL is given, no index.html is found and CGI support is enabled,
  25  * cgi-bin/index.cgi will be run. Directory to list is ../$QUERY_STRING.
  26  * See httpd_indexcgi.c for an example GCI code.
  27  *
  28  * Doc:
  29  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
  30  *
  31  * The applet can also be invoked as an url arg decoder and html text encoder
  32  * as follows:
  33  *      foo=`httpd -d $foo`             # decode "Hello%20World" as "Hello World"
  34  *      bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
  35  * Note that url encoding for arguments is not the same as html encoding for
  36  * presentation.  -d decodes an url-encoded argument while -e encodes in html
  37  * for page display.
  38  *
  39  * httpd.conf has the following format:
  40  *
  41  * H:/serverroot     # define the server root. It will override -h
  42  * A:172.20.         # Allow address from 172.20.0.0/16
  43  * A:10.0.0.0/25     # Allow any address from 10.0.0.0-10.0.0.127
  44  * A:10.0.0.0/255.255.255.128  # Allow any address that previous set
  45  * A:127.0.0.1       # Allow local loopback connections
  46  * D:*               # Deny from other IP connections
  47  * E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
  48  * I:index.html      # Show index.html when a directory is requested
  49  *
  50  * P:/url:[http://]hostname[:port]/new/path
  51  *                   # When /urlXXXXXX is requested, reverse proxy
  52  *                   # it to http://hostname[:port]/new/pathXXXXXX
  53  *
  54  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
  55  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
  56  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
  57  * .au:audio/basic   # additional mime type for audio.au files
  58  * *.php:/path/php   # run xxx.php through an interpreter
  59  *
  60  * A/D may be as a/d or allow/deny - only first char matters.
  61  * Deny/Allow IP logic:
  62  *  - Default is to allow all (Allow all (A:*) is a no-op).
  63  *  - Deny rules take precedence over allow rules.
  64  *  - "Deny all" rule (D:*) is applied last.
  65  *
  66  * Example:
  67  *   1. Allow only specified addresses
  68  *     A:172.20          # Allow any address that begins with 172.20.
  69  *     A:10.10.          # Allow any address that begins with 10.10.
  70  *     A:127.0.0.1       # Allow local loopback connections
  71  *     D:*               # Deny from other IP connections
  72  *
  73  *   2. Only deny specified addresses
  74  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
  75  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
  76  *     A:*             # (optional line added for clarity)
  77  *
  78  * If a sub directory contains config file, it is parsed and merged with
  79  * any existing settings as if it was appended to the original configuration.
  80  *
  81  * subdir paths are relative to the containing subdir and thus cannot
  82  * affect the parent rules.
  83  *
  84  * Note that since the sub dir is parsed in the forked thread servicing the
  85  * subdir http request, any merge is discarded when the process exits.  As a
  86  * result, the subdir settings only have a lifetime of a single request.
  87  *
  88  * Custom error pages can contain an absolute path or be relative to
  89  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
  90  * page can only be defined in the root configuration file and are not taken
  91  * into account in local (directories) config files.
  92  *
  93  * If -c is not set, an attempt will be made to open the default
  94  * root configuration file.  If -c is set and the file is not found, the
  95  * server exits with an error.
  96  *
  97  */
  98  /* TODO: use TCP_CORK, parse_config() */
  99
 100 //usage:#define httpd_trivial_usage
 101 //usage:       "[-ifv[v]]"
 102 //usage:       " [-c CONFFILE]"
 103 //usage:       " [-p [IP:]PORT]"
 104 //usage:        IF_FEATURE_HTTPD_SETUID(" [-u USER[:GRP]]")
 105 //usage:        IF_FEATURE_HTTPD_BASIC_AUTH(" [-r REALM]")
 106 //usage:       " [-h HOME]\n"
 107 //usage:       "or httpd -d/-e" IF_FEATURE_HTTPD_AUTH_MD5("/-m") " STRING"
 108 //usage:#define httpd_full_usage "\n\n"
 109 //usage:       "Listen for incoming HTTP requests\n"
 110 //usage:     "\n        -i              Inetd mode"
 111 //usage:     "\n        -f              Don't daemonize"
 112 //usage:     "\n        -v[v]           Verbose"
 113 //usage:     "\n        -p [IP:]PORT    Bind to IP:PORT (default *:80)"
 114 //usage:        IF_FEATURE_HTTPD_SETUID(
 115 //usage:     "\n        -u USER[:GRP]   Set uid/gid after binding to port")
 116 //usage:        IF_FEATURE_HTTPD_BASIC_AUTH(
 117 //usage:     "\n        -r REALM        Authentication Realm for Basic Authentication")
 118 //usage:     "\n        -h HOME         Home directory (default .)"
 119 //usage:     "\n        -c FILE         Configuration file (default {/etc,HOME}/httpd.conf)"
 120 //usage:        IF_FEATURE_HTTPD_AUTH_MD5(
 121 //usage:     "\n        -m STRING       MD5 crypt STRING")
 122 //usage:     "\n        -e STRING       HTML encode STRING"
 123 //usage:     "\n        -d STRING       URL decode STRING"
 124
 125 #include "libbb.h"
 126 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
 127 # include <sys/sendfile.h>
 128 #endif
 129 /* amount of buffering in a pipe */
 130 #ifndef PIPE_BUF
 131 # define PIPE_BUF 4096
 132 #endif
 133
 134 #define DEBUG 0
 135
 136 #define IOBUF_SIZE 8192
 137 #if PIPE_BUF >= IOBUF_SIZE
 138 # error "PIPE_BUF >= IOBUF_SIZE"
 139 #endif
 140
 141 #define HEADER_READ_TIMEOUT 60
 142
 143 static const char DEFAULT_PATH_HTTPD_CONF[] ALIGN1 = "/etc";
 144 static const char HTTPD_CONF[] ALIGN1 = "httpd.conf";
 145 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
 146 static const char index_html[] ALIGN1 = "index.html";
 147
 148 typedef struct has_next_ptr {
 149         struct has_next_ptr *next;
 150 } has_next_ptr;
 151
 152 /* Must have "next" as a first member */
 153 typedef struct Htaccess {
 154         struct Htaccess *next;
 155         char *after_colon;
 156         char before_colon[1];  /* really bigger, must be last */
 157 } Htaccess;
 158
 159 /* Must have "next" as a first member */
 160 typedef struct Htaccess_IP {
 161         struct Htaccess_IP *next;
 162         unsigned ip;
 163         unsigned mask;
 164         int allow_deny;
 165 } Htaccess_IP;
 166
 167 /* Must have "next" as a first member */
 168 typedef struct Htaccess_Proxy {
 169         struct Htaccess_Proxy *next;
 170         char *url_from;
 171         char *host_port;
 172         char *url_to;
 173 } Htaccess_Proxy;
 174
 175 enum {
 176         HTTP_OK = 200,
 177         HTTP_PARTIAL_CONTENT = 206,
 178         HTTP_MOVED_TEMPORARILY = 302,
 179         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
 180         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
 181         HTTP_NOT_FOUND = 404,
 182         HTTP_FORBIDDEN = 403,
 183         HTTP_REQUEST_TIMEOUT = 408,
 184         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
 185         HTTP_INTERNAL_SERVER_ERROR = 500,
 186         HTTP_CONTINUE = 100,
 187 #if 0   /* future use */
 188         HTTP_SWITCHING_PROTOCOLS = 101,
 189         HTTP_CREATED = 201,
 190         HTTP_ACCEPTED = 202,
 191         HTTP_NON_AUTHORITATIVE_INFO = 203,
 192         HTTP_NO_CONTENT = 204,
 193         HTTP_MULTIPLE_CHOICES = 300,
 194         HTTP_MOVED_PERMANENTLY = 301,
 195         HTTP_NOT_MODIFIED = 304,
 196         HTTP_PAYMENT_REQUIRED = 402,
 197         HTTP_BAD_GATEWAY = 502,
 198         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
 199 #endif
 200 };
 201
 202 static const uint16_t http_response_type[] ALIGN2 = {
 203         HTTP_OK,
 204 #if ENABLE_FEATURE_HTTPD_RANGES
 205         HTTP_PARTIAL_CONTENT,
 206 #endif
 207         HTTP_MOVED_TEMPORARILY,
 208         HTTP_REQUEST_TIMEOUT,
 209         HTTP_NOT_IMPLEMENTED,
 210 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 211         HTTP_UNAUTHORIZED,
 212 #endif
 213         HTTP_NOT_FOUND,
 214         HTTP_BAD_REQUEST,
 215         HTTP_FORBIDDEN,
 216         HTTP_INTERNAL_SERVER_ERROR,
 217 #if 0   /* not implemented */
 218         HTTP_CREATED,
 219         HTTP_ACCEPTED,
 220         HTTP_NO_CONTENT,
 221         HTTP_MULTIPLE_CHOICES,
 222         HTTP_MOVED_PERMANENTLY,
 223         HTTP_NOT_MODIFIED,
 224         HTTP_BAD_GATEWAY,
 225         HTTP_SERVICE_UNAVAILABLE,
 226 #endif
 227 };
 228
 229 static const struct {
 230         const char *name;
 231         const char *info;
 232 } http_response[ARRAY_SIZE(http_response_type)] = {
 233         { "OK", NULL },
 234 #if ENABLE_FEATURE_HTTPD_RANGES
 235         { "Partial Content", NULL },
 236 #endif
 237         { "Found", NULL },
 238         { "Request Timeout", "No request appeared within 60 seconds" },
 239         { "Not Implemented", "The requested method is not recognized" },
 240 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 241         { "Unauthorized", "" },
 242 #endif
 243         { "Not Found", "The requested URL was not found" },
 244         { "Bad Request", "Unsupported method" },
 245         { "Forbidden", ""  },
 246         { "Internal Server Error", "Internal Server Error" },
 247 #if 0   /* not implemented */
 248         { "Created" },
 249         { "Accepted" },
 250         { "No Content" },
 251         { "Multiple Choices" },
 252         { "Moved Permanently" },
 253         { "Not Modified" },
 254         { "Bad Gateway", "" },
 255         { "Service Unavailable", "" },
 256 #endif
 257 };
 258
 259 struct globals {
 260         int verbose;            /* must be int (used by getopt32) */
 261         smallint flg_deny_all;
 262
 263         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
 264         time_t last_mod;
 265         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
 266         const char *bind_addr_or_port;
 267
 268         const char *g_query;
 269         const char *opt_c_configFile;
 270         const char *home_httpd;
 271         const char *index_page;
 272
 273         const char *found_mime_type;
 274         const char *found_moved_temporarily;
 275         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 276
 277         IF_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
 278         IF_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
 279         IF_FEATURE_HTTPD_CGI(char *referer;)
 280         IF_FEATURE_HTTPD_CGI(char *user_agent;)
 281         IF_FEATURE_HTTPD_CGI(char *host;)
 282         IF_FEATURE_HTTPD_CGI(char *http_accept;)
 283         IF_FEATURE_HTTPD_CGI(char *http_accept_language;)
 284
 285         off_t file_size;        /* -1 - unknown */
 286 #if ENABLE_FEATURE_HTTPD_RANGES
 287         off_t range_start;
 288         off_t range_end;
 289         off_t range_len;
 290 #endif
 291
 292 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 293         Htaccess *g_auth;       /* config user:password lines */
 294 #endif
 295         Htaccess *mime_a;       /* config mime types */
 296 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 297         Htaccess *script_i;     /* config script interpreters */
 298 #endif
 299         char *iobuf;            /* [IOBUF_SIZE] */
 300 #define hdr_buf bb_common_bufsiz1
 301         char *hdr_ptr;
 302         int hdr_cnt;
 303 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 304         const char *http_error_page[ARRAY_SIZE(http_response_type)];
 305 #endif
 306 #if ENABLE_FEATURE_HTTPD_PROXY
 307         Htaccess_Proxy *proxy;
 308 #endif
 309 #if ENABLE_FEATURE_HTTPD_GZIP
 310         /* client can handle gzip / we are going to send gzip */
 311         smallint content_gzip;
 312 #endif
 313 };
 314 #define G (*ptr_to_globals)
 315 #define verbose           (G.verbose          )
 316 #define flg_deny_all      (G.flg_deny_all     )
 317 #define rmt_ip            (G.rmt_ip           )
 318 #define bind_addr_or_port (G.bind_addr_or_port)
 319 #define g_query           (G.g_query          )
 320 #define opt_c_configFile  (G.opt_c_configFile )
 321 #define home_httpd        (G.home_httpd       )
 322 #define index_page        (G.index_page       )
 323 #define found_mime_type   (G.found_mime_type  )
 324 #define found_moved_temporarily (G.found_moved_temporarily)
 325 #define last_mod          (G.last_mod         )
 326 #define ip_a_d            (G.ip_a_d           )
 327 #define g_realm           (G.g_realm          )
 328 #define remoteuser        (G.remoteuser       )
 329 #define referer           (G.referer          )
 330 #define user_agent        (G.user_agent       )
 331 #define host              (G.host             )
 332 #define http_accept       (G.http_accept      )
 333 #define http_accept_language (G.http_accept_language)
 334 #define file_size         (G.file_size        )
 335 #if ENABLE_FEATURE_HTTPD_RANGES
 336 #define range_start       (G.range_start      )
 337 #define range_end         (G.range_end        )
 338 #define range_len         (G.range_len        )
 339 #else
 340 enum {
 341         range_start = 0,
 342         range_end = MAXINT(off_t) - 1,
 343         range_len = MAXINT(off_t),
 344 };
 345 #endif
 346 #define rmt_ip_str        (G.rmt_ip_str       )
 347 #define g_auth            (G.g_auth           )
 348 #define mime_a            (G.mime_a           )
 349 #define script_i          (G.script_i         )
 350 #define iobuf             (G.iobuf            )
 351 #define hdr_ptr           (G.hdr_ptr          )
 352 #define hdr_cnt           (G.hdr_cnt          )
 353 #define http_error_page   (G.http_error_page  )
 354 #define proxy             (G.proxy            )
 355 #if ENABLE_FEATURE_HTTPD_GZIP
 356 # define content_gzip     (G.content_gzip     )
 357 #else
 358 # define content_gzip     0
 359 #endif
 360 #define INIT_G() do { \
 361         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 362         IF_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
 363         bind_addr_or_port = "80"; \
 364         index_page = index_html; \
 365         file_size = -1; \
 366 } while (0)
 367
 368
 369 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
 370
 371 /* Prototypes */
 372 enum {
 373         SEND_HEADERS     = (1 << 0),
 374         SEND_BODY        = (1 << 1),
 375         SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
 376 };
 377 static void send_file_and_exit(const char *url, int what) NORETURN;
 378
 379 static void free_llist(has_next_ptr **pptr)
 380 {
 381         has_next_ptr *cur = *pptr;
 382         while (cur) {
 383                 has_next_ptr *t = cur;
 384                 cur = cur->next;
 385                 free(t);
 386         }
 387         *pptr = NULL;
 388 }
 389
 390 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 391 {
 392         free_llist((has_next_ptr**)pptr);
 393 }
 394
 395 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 396 {
 397         free_llist((has_next_ptr**)pptr);
 398 }
 399
 400 /* Returns presumed mask width in bits or < 0 on error.
 401  * Updates strp, stores IP at provided pointer */
 402 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 403 {
 404         const char *p = *strp;
 405         int auto_mask = 8;
 406         unsigned ip = 0;
 407         int j;
 408
 409         if (*p == '/')
 410                 return -auto_mask;
 411
 412         for (j = 0; j < 4; j++) {
 413                 unsigned octet;
 414
 415                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
 416                         return -auto_mask;
 417                 octet = 0;
 418                 while (*p >= '0' && *p <= '9') {
 419                         octet *= 10;
 420                         octet += *p - '0';
 421                         if (octet > 255)
 422                                 return -auto_mask;
 423                         p++;
 424                 }
 425                 if (*p == '.')
 426                         p++;
 427                 if (*p != '/' && *p)
 428                         auto_mask += 8;
 429                 ip = (ip << 8) | octet;
 430         }
 431         if (*p) {
 432                 if (*p != endc)
 433                         return -auto_mask;
 434                 p++;
 435                 if (*p == '\0')
 436                         return -auto_mask;
 437         }
 438         *ipp = ip;
 439         *strp = p;
 440         return auto_mask;
 441 }
 442
 443 /* Returns 0 on success. Stores IP and mask at provided pointers */
 444 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 445 {
 446         int i;
 447         unsigned mask;
 448         char *p;
 449
 450         i = scan_ip(&str, ipp, '/');
 451         if (i < 0)
 452                 return i;
 453
 454         if (*str) {
 455                 /* there is /xxx after dotted-IP address */
 456                 i = bb_strtou(str, &p, 10);
 457                 if (*p == '.') {
 458                         /* 'xxx' itself is dotted-IP mask, parse it */
 459                         /* (return 0 (success) only if it has N.N.N.N form) */
 460                         return scan_ip(&str, maskp, '\0') - 32;
 461                 }
 462                 if (*p)
 463                         return -1;
 464         }
 465
 466         if (i > 32)
 467                 return -1;
 468
 469         if (sizeof(unsigned) == 4 && i == 32) {
 470                 /* mask >>= 32 below may not work */
 471                 mask = 0;
 472         } else {
 473                 mask = 0xffffffff;
 474                 mask >>= i;
 475         }
 476         /* i == 0 -> *maskp = 0x00000000
 477          * i == 1 -> *maskp = 0x80000000
 478          * i == 4 -> *maskp = 0xf0000000
 479          * i == 31 -> *maskp = 0xfffffffe
 480          * i == 32 -> *maskp = 0xffffffff */
 481         *maskp = (uint32_t)(~mask);
 482         return 0;
 483 }
 484
 485 /*
 486  * Parse configuration file into in-memory linked list.
 487  *
 488  * Any previous IP rules are discarded.
 489  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
 490  * are also discarded.  That is, previous settings are retained if flag is
 491  * SUBDIR_PARSE.
 492  * Error pages are only parsed on the main config file.
 493  *
 494  * path   Path where to look for httpd.conf (without filename).
 495  * flag   Type of the parse request.
 496  */
 497 /* flag param: */
 498 enum {
 499         FIRST_PARSE    = 0, /* path will be "/etc" */
 500         SIGNALED_PARSE = 1, /* path will be "/etc" */
 501         SUBDIR_PARSE   = 2, /* path will be derived from URL */
 502 };
 503 static void parse_conf(const char *path, int flag)
 504 {
 505         /* internally used extra flag state */
 506         enum { TRY_CURDIR_PARSE = 3 };
 507
 508         FILE *f;
 509         const char *filename;
 510         char buf[160];
 511
 512         /* discard old rules */
 513         free_Htaccess_IP_list(&ip_a_d);
 514         flg_deny_all = 0;
 515         /* retain previous auth and mime config only for subdir parse */
 516         if (flag != SUBDIR_PARSE) {
 517                 free_Htaccess_list(&mime_a);
 518 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 519                 free_Htaccess_list(&g_auth);
 520 #endif
 521 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 522                 free_Htaccess_list(&script_i);
 523 #endif
 524         }
 525
 526         filename = opt_c_configFile;
 527         if (flag == SUBDIR_PARSE || filename == NULL) {
 528                 filename = alloca(strlen(path) + sizeof(HTTPD_CONF) + 2);
 529                 sprintf((char *)filename, "%s/%s", path, HTTPD_CONF);
 530         }
 531
 532         while ((f = fopen_for_read(filename)) == NULL) {
 533                 if (flag >= SUBDIR_PARSE) { /* SUBDIR or TRY_CURDIR */
 534                         /* config file not found, no changes to config */
 535                         return;
 536                 }
 537                 if (flag == FIRST_PARSE) {
 538                         /* -c CONFFILE given, but CONFFILE doesn't exist? */
 539                         if (opt_c_configFile)
 540                                 bb_simple_perror_msg_and_die(opt_c_configFile);
 541                         /* else: no -c, thus we looked at /etc/httpd.conf,
 542                          * and it's not there. try ./httpd.conf: */
 543                 }
 544                 flag = TRY_CURDIR_PARSE;
 545                 filename = HTTPD_CONF;
 546         }
 547
 548 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 549         /* in "/file:user:pass" lines, we prepend path in subdirs */
 550         if (flag != SUBDIR_PARSE)
 551                 path = "";
 552 #endif
 553         /* The lines can be:
 554          *
 555          * I:default_index_file
 556          * H:http_home
 557          * [AD]:IP[/mask]   # allow/deny, * for wildcard
 558          * Ennn:error.html  # error page for status nnn
 559          * P:/url:[http://]hostname[:port]/new/path # reverse proxy
 560          * .ext:mime/type   # mime type
 561          * *.php:/path/php  # run xxx.php through an interpreter
 562          * /file:user:pass  # username and password
 563          */
 564         while (fgets(buf, sizeof(buf), f) != NULL) {
 565                 unsigned strlen_buf;
 566                 unsigned char ch;
 567                 char *after_colon;
 568
 569                 { /* remove all whitespace, and # comments */
 570                         char *p, *p0;
 571
 572                         p0 = buf;
 573                         /* skip non-whitespace beginning. Often the whole line
 574                          * is non-whitespace. We want this case to work fast,
 575                          * without needless copying, therefore we don't merge
 576                          * this operation into next while loop. */
 577                         while ((ch = *p0) != '\0' && ch != '\n' && ch != '#'
 578                          && ch != ' ' && ch != '\t'
 579                         ) {
 580                                 p0++;
 581                         }
 582                         p = p0;
 583                         /* if we enter this loop, we have some whitespace.
 584                          * discard it */
 585                         while (ch != '\0' && ch != '\n' && ch != '#') {
 586                                 if (ch != ' ' && ch != '\t') {
 587                                         *p++ = ch;
 588                                 }
 589                                 ch = *++p0;
 590                         }
 591                         *p = '\0';
 592                         strlen_buf = p - buf;
 593                         if (strlen_buf == 0)
 594                                 continue; /* empty line */
 595                 }
 596
 597                 after_colon = strchr(buf, ':');
 598                 /* strange line? */
 599                 if (after_colon == NULL || *++after_colon == '\0')
 600                         goto config_error;
 601
 602                 ch = (buf[0] & ~0x20); /* toupper if it's a letter */
 603
 604                 if (ch == 'I') {
 605                         if (index_page != index_html)
 606                                 free((char*)index_page);
 607                         index_page = xstrdup(after_colon);
 608                         continue;
 609                 }
 610
 611                 /* do not allow jumping around using H in subdir's configs */
 612                 if (flag == FIRST_PARSE && ch == 'H') {
 613                         home_httpd = xstrdup(after_colon);
 614                         xchdir(home_httpd);
 615                         continue;
 616                 }
 617
 618                 if (ch == 'A' || ch == 'D') {
 619                         Htaccess_IP *pip;
 620
 621                         if (*after_colon == '*') {
 622                                 if (ch == 'D') {
 623                                         /* memorize "deny all" */
 624                                         flg_deny_all = 1;
 625                                 }
 626                                 /* skip assumed "A:*", it is a default anyway */
 627                                 continue;
 628                         }
 629                         /* store "allow/deny IP/mask" line */
 630                         pip = xzalloc(sizeof(*pip));
 631                         if (scan_ip_mask(after_colon, &pip->ip, &pip->mask)) {
 632                                 /* IP{/mask} syntax error detected, protect all */
 633                                 ch = 'D';
 634                                 pip->mask = 0;
 635                         }
 636                         pip->allow_deny = ch;
 637                         if (ch == 'D') {
 638                                 /* Deny:from_IP - prepend */
 639                                 pip->next = ip_a_d;
 640                                 ip_a_d = pip;
 641                         } else {
 642                                 /* A:from_IP - append (thus all D's precedes A's) */
 643                                 Htaccess_IP *prev_IP = ip_a_d;
 644                                 if (prev_IP == NULL) {
 645                                         ip_a_d = pip;
 646                                 } else {
 647                                         while (prev_IP->next)
 648                                                 prev_IP = prev_IP->next;
 649                                         prev_IP->next = pip;
 650                                 }
 651                         }
 652                         continue;
 653                 }
 654
 655 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 656                 if (flag == FIRST_PARSE && ch == 'E') {
 657                         unsigned i;
 658                         int status = atoi(buf + 1); /* error status code */
 659
 660                         if (status < HTTP_CONTINUE) {
 661                                 goto config_error;
 662                         }
 663                         /* then error page; find matching status */
 664                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 665                                 if (http_response_type[i] == status) {
 666                                         /* We chdir to home_httpd, thus no need to
 667                                          * concat_path_file(home_httpd, after_colon)
 668                                          * here */
 669                                         http_error_page[i] = xstrdup(after_colon);
 670                                         break;
 671                                 }
 672                         }
 673                         continue;
 674                 }
 675 #endif
 676
 677 #if ENABLE_FEATURE_HTTPD_PROXY
 678                 if (flag == FIRST_PARSE && ch == 'P') {
 679                         /* P:/url:[http://]hostname[:port]/new/path */
 680                         char *url_from, *host_port, *url_to;
 681                         Htaccess_Proxy *proxy_entry;
 682
 683                         url_from = after_colon;
 684                         host_port = strchr(after_colon, ':');
 685                         if (host_port == NULL) {
 686                                 goto config_error;
 687                         }
 688                         *host_port++ = '\0';
 689                         if (strncmp(host_port, "http://", 7) == 0)
 690                                 host_port += 7;
 691                         if (*host_port == '\0') {
 692                                 goto config_error;
 693                         }
 694                         url_to = strchr(host_port, '/');
 695                         if (url_to == NULL) {
 696                                 goto config_error;
 697                         }
 698                         *url_to = '\0';
 699                         proxy_entry = xzalloc(sizeof(*proxy_entry));
 700                         proxy_entry->url_from = xstrdup(url_from);
 701                         proxy_entry->host_port = xstrdup(host_port);
 702                         *url_to = '/';
 703                         proxy_entry->url_to = xstrdup(url_to);
 704                         proxy_entry->next = proxy;
 705                         proxy = proxy_entry;
 706                         continue;
 707                 }
 708 #endif
 709                 /* the rest of directives are non-alphabetic,
 710                  * must avoid using "toupper'ed" ch */
 711                 ch = buf[0];
 712
 713                 if (ch == '.' /* ".ext:mime/type" */
 714 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 715                  || (ch == '*' && buf[1] == '.') /* "*.php:/path/php" */
 716 #endif
 717                 ) {
 718                         char *p;
 719                         Htaccess *cur;
 720
 721                         cur = xzalloc(sizeof(*cur) /* includes space for NUL */ + strlen_buf);
 722                         strcpy(cur->before_colon, buf);
 723                         p = cur->before_colon + (after_colon - buf);
 724                         p[-1] = '\0';
 725                         cur->after_colon = p;
 726                         if (ch == '.') {
 727                                 /* .mime line: prepend to mime_a list */
 728                                 cur->next = mime_a;
 729                                 mime_a = cur;
 730                         }
 731 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 732                         else {
 733                                 /* script interpreter line: prepend to script_i list */
 734                                 cur->next = script_i;
 735                                 script_i = cur;
 736                         }
 737 #endif
 738                         continue;
 739                 }
 740
 741 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 742                 if (ch == '/') { /* "/file:user:pass" */
 743                         char *p;
 744                         Htaccess *cur;
 745                         unsigned file_len;
 746
 747                         /* note: path is "" unless we are in SUBDIR parse,
 748                          * otherwise it does NOT start with "/" */
 749                         cur = xzalloc(sizeof(*cur) /* includes space for NUL */
 750                                 + 1 + strlen(path)
 751                                 + strlen_buf
 752                                 );
 753                         /* form "/path/file" */
 754                         sprintf(cur->before_colon, "/%s%.*s",
 755                                 path,
 756                                 (int) (after_colon - buf - 1), /* includes "/", but not ":" */
 757                                 buf);
 758                         /* canonicalize it */
 759                         p = bb_simplify_abs_path_inplace(cur->before_colon);
 760                         file_len = p - cur->before_colon;
 761                         /* add "user:pass" after NUL */
 762                         strcpy(++p, after_colon);
 763                         cur->after_colon = p;
 764
 765                         /* insert cur into g_auth */
 766                         /* g_auth is sorted by decreased filename length */
 767                         {
 768                                 Htaccess *auth, **authp;
 769
 770                                 authp = &g_auth;
 771                                 while ((auth = *authp) != NULL) {
 772                                         if (file_len >= strlen(auth->before_colon)) {
 773                                                 /* insert cur before auth */
 774                                                 cur->next = auth;
 775                                                 break;
 776                                         }
 777                                         authp = &auth->next;
 778                                 }
 779                                 *authp = cur;
 780                         }
 781                         continue;
 782                 }
 783 #endif /* BASIC_AUTH */
 784
 785                 /* the line is not recognized */
 786  config_error:
 787                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 788          } /* while (fgets) */
 789
 790          fclose(f);
 791 }
 792
 793 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
 794 /*
 795  * Given a string, html-encode special characters.
 796  * This is used for the -e command line option to provide an easy way
 797  * for scripts to encode result data without confusing browsers.  The
 798  * returned string pointer is memory allocated by malloc().
 799  *
 800  * Returns a pointer to the encoded string (malloced).
 801  */
 802 static char *encodeString(const char *string)
 803 {
 804         /* take the simple route and encode everything */
 805         /* could possibly scan once to get length.     */
 806         int len = strlen(string);
 807         char *out = xmalloc(len * 6 + 1);
 808         char *p = out;
 809         char ch;
 810
 811         while ((ch = *string++) != '\0') {
 812                 /* very simple check for what to encode */
 813                 if (isalnum(ch))
 814                         *p++ = ch;
 815                 else
 816                         p += sprintf(p, "&#%d;", (unsigned char) ch);
 817         }
 818         *p = '\0';
 819         return out;
 820 }
 821 #endif
 822
 823 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 824 /*
 825  * Decode a base64 data stream as per rfc1521.
 826  * Note that the rfc states that non base64 chars are to be ignored.
 827  * Since the decode always results in a shorter size than the input,
 828  * it is OK to pass the input arg as an output arg.
 829  * Parameter: a pointer to a base64 encoded string.
 830  * Decoded data is stored in-place.
 831  */
 832 static void decodeBase64(char *Data)
 833 {
 834         const unsigned char *in = (const unsigned char *)Data;
 835         /* The decoded size will be at most 3/4 the size of the encoded */
 836         unsigned ch = 0;
 837         int i = 0;
 838
 839         while (*in) {
 840                 int t = *in++;
 841
 842                 if (t >= '0' && t <= '9')
 843                         t = t - '0' + 52;
 844                 else if (t >= 'A' && t <= 'Z')
 845                         t = t - 'A';
 846                 else if (t >= 'a' && t <= 'z')
 847                         t = t - 'a' + 26;
 848                 else if (t == '+')
 849                         t = 62;
 850                 else if (t == '/')
 851                         t = 63;
 852                 else if (t == '=')
 853                         t = 0;
 854                 else
 855                         continue;
 856
 857                 ch = (ch << 6) | t;
 858                 i++;
 859                 if (i == 4) {
 860                         *Data++ = (char) (ch >> 16);
 861                         *Data++ = (char) (ch >> 8);
 862                         *Data++ = (char) ch;
 863                         i = 0;
 864                 }
 865         }
 866         *Data = '\0';
 867 }
 868 #endif
 869
 870 /*
 871  * Create a listen server socket on the designated port.
 872  */
 873 static int openServer(void)
 874 {
 875         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 876         if (!errno && n && n <= 0xffff)
 877                 n = create_and_bind_stream_or_die(NULL, n);
 878         else
 879                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 880         xlisten(n, 9);
 881         return n;
 882 }
 883
 884 /*
 885  * Log the connection closure and exit.
 886  */
 887 static void log_and_exit(void) NORETURN;
 888 static void log_and_exit(void)
 889 {
 890         /* Paranoia. IE said to be buggy. It may send some extra data
 891          * or be confused by us just exiting without SHUT_WR. Oh well. */
 892         shutdown(1, SHUT_WR);
 893         /* Why??
 894         (this also messes up stdin when user runs httpd -i from terminal)
 895         ndelay_on(0);
 896         while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
 897                 continue;
 898         */
 899
 900         if (verbose > 2)
 901                 bb_error_msg("closed");
 902         _exit(xfunc_error_retval);
 903 }
 904
 905 /*
 906  * Create and send HTTP response headers.
 907  * The arguments are combined and sent as one write operation.  Note that
 908  * IE will puke big-time if the headers are not sent in one packet and the
 909  * second packet is delayed for any reason.
 910  * responseNum - the result code to send.
 911  */
 912 static void send_headers(int responseNum)
 913 {
 914         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 915
 916         const char *responseString = "";
 917         const char *infoString = NULL;
 918         const char *mime_type;
 919 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 920         const char *error_page = NULL;
 921 #endif
 922         unsigned i;
 923         time_t timer = time(NULL);
 924         char tmp_str[80];
 925         int len;
 926
 927         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 928                 if (http_response_type[i] == responseNum) {
 929                         responseString = http_response[i].name;
 930                         infoString = http_response[i].info;
 931 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 932                         error_page = http_error_page[i];
 933 #endif
 934                         break;
 935                 }
 936         }
 937         /* error message is HTML */
 938         mime_type = responseNum == HTTP_OK ?
 939                                 found_mime_type : "text/html";
 940
 941         if (verbose)
 942                 bb_error_msg("response:%u", responseNum);
 943
 944         /* emit the current date */
 945         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
 946         len = sprintf(iobuf,
 947                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
 948                         "Date: %s\r\nConnection: close\r\n",
 949                         responseNum, responseString, mime_type, tmp_str);
 950
 951 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 952         if (responseNum == HTTP_UNAUTHORIZED) {
 953                 len += sprintf(iobuf + len,
 954                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
 955                                 g_realm);
 956         }
 957 #endif
 958         if (responseNum == HTTP_MOVED_TEMPORARILY) {
 959                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
 960                                 found_moved_temporarily,
 961                                 (g_query ? "?" : ""),
 962                                 (g_query ? g_query : ""));
 963         }
 964
 965 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 966         if (error_page && access(error_page, R_OK) == 0) {
 967                 strcat(iobuf, "\r\n");
 968                 len += 2;
 969
 970                 if (DEBUG)
 971                         fprintf(stderr, "headers: '%s'\n", iobuf);
 972                 full_write(STDOUT_FILENO, iobuf, len);
 973                 if (DEBUG)
 974                         fprintf(stderr, "writing error page: '%s'\n", error_page);
 975                 return send_file_and_exit(error_page, SEND_BODY);
 976         }
 977 #endif
 978
 979         if (file_size != -1) {    /* file */
 980                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
 981 #if ENABLE_FEATURE_HTTPD_RANGES
 982                 if (responseNum == HTTP_PARTIAL_CONTENT) {
 983                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"u-%"OFF_FMT"u/%"OFF_FMT"u\r\n",
 984                                         range_start,
 985                                         range_end,
 986                                         file_size);
 987                         file_size = range_end - range_start + 1;
 988                 }
 989 #endif
 990                 len += sprintf(iobuf + len,
 991 #if ENABLE_FEATURE_HTTPD_RANGES
 992                         "Accept-Ranges: bytes\r\n"
 993 #endif
 994                         "Last-Modified: %s\r\n%s %"OFF_FMT"u\r\n",
 995                                 tmp_str,
 996                                 content_gzip ? "Transfer-length:" : "Content-length:",
 997                                 file_size
 998                 );
 999         }
1000
1001         if (content_gzip)
1002                 len += sprintf(iobuf + len, "Content-Encoding: gzip\r\n");
1003
1004         iobuf[len++] = '\r';
1005         iobuf[len++] = '\n';
1006         if (infoString) {
1007                 len += sprintf(iobuf + len,
1008                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1009                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1010                                 responseNum, responseString,
1011                                 responseNum, responseString, infoString);
1012         }
1013         if (DEBUG)
1014                 fprintf(stderr, "headers: '%s'\n", iobuf);
1015         if (full_write(STDOUT_FILENO, iobuf, len) != len) {
1016                 if (verbose > 1)
1017                         bb_perror_msg("error");
1018                 log_and_exit();
1019         }
1020 }
1021
1022 static void send_headers_and_exit(int responseNum) NORETURN;
1023 static void send_headers_and_exit(int responseNum)
1024 {
1025         IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
1026         send_headers(responseNum);
1027         log_and_exit();
1028 }
1029
1030 /*
1031  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1032  * '\n' is replaced with NUL.
1033  * Return number of characters read or 0 if nothing is read
1034  * ('\r' and '\n' are not counted).
1035  * Data is returned in iobuf.
1036  */
1037 static int get_line(void)
1038 {
1039         int count = 0;
1040         char c;
1041
1042         alarm(HEADER_READ_TIMEOUT);
1043         while (1) {
1044                 if (hdr_cnt <= 0) {
1045                         hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1046                         if (hdr_cnt <= 0)
1047                                 break;
1048                         hdr_ptr = hdr_buf;
1049                 }
1050                 iobuf[count] = c = *hdr_ptr++;
1051                 hdr_cnt--;
1052
1053                 if (c == '\r')
1054                         continue;
1055                 if (c == '\n') {
1056                         iobuf[count] = '\0';
1057                         break;
1058                 }
1059                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1060                         count++;
1061         }
1062         return count;
1063 }
1064
1065 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1066
1067 /* gcc 4.2.1 fares better with NOINLINE */
1068 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
1069 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1070 {
1071         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1072         struct pollfd pfd[3];
1073         int out_cnt; /* we buffer a bit of initial CGI output */
1074         int count;
1075
1076         /* iobuf is used for CGI -> network data,
1077          * hdr_buf is for network -> CGI data (POSTDATA) */
1078
1079         /* If CGI dies, we still want to correctly finish reading its output
1080          * and send it to the peer. So please no SIGPIPEs! */
1081         signal(SIGPIPE, SIG_IGN);
1082
1083         // We inconsistently handle a case when more POSTDATA from network
1084         // is coming than we expected. We may give *some part* of that
1085         // extra data to CGI.
1086
1087         //if (hdr_cnt > post_len) {
1088         //      /* We got more POSTDATA from network than we expected */
1089         //      hdr_cnt = post_len;
1090         //}
1091         post_len -= hdr_cnt;
1092         /* post_len - number of POST bytes not yet read from network */
1093
1094         /* NB: breaking out of this loop jumps to log_and_exit() */
1095         out_cnt = 0;
1096         while (1) {
1097                 memset(pfd, 0, sizeof(pfd));
1098
1099                 pfd[FROM_CGI].fd = fromCgi_rd;
1100                 pfd[FROM_CGI].events = POLLIN;
1101
1102                 if (toCgi_wr) {
1103                         pfd[TO_CGI].fd = toCgi_wr;
1104                         if (hdr_cnt > 0) {
1105                                 pfd[TO_CGI].events = POLLOUT;
1106                         } else if (post_len > 0) {
1107                                 pfd[0].events = POLLIN;
1108                         } else {
1109                                 /* post_len <= 0 && hdr_cnt <= 0:
1110                                  * no more POST data to CGI,
1111                                  * let CGI see EOF on CGI's stdin */
1112                                 if (toCgi_wr != fromCgi_rd)
1113                                         close(toCgi_wr);
1114                                 toCgi_wr = 0;
1115                         }
1116                 }
1117
1118                 /* Now wait on the set of sockets */
1119                 count = safe_poll(pfd, toCgi_wr ? TO_CGI+1 : FROM_CGI+1, -1);
1120                 if (count <= 0) {
1121 #if 0
1122                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1123                                 /* Weird. CGI didn't exit and no fd's
1124                                  * are ready, yet poll returned?! */
1125                                 continue;
1126                         }
1127                         if (DEBUG && WIFEXITED(status))
1128                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1129                         if (DEBUG && WIFSIGNALED(status))
1130                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1131 #endif
1132                         break;
1133                 }
1134
1135                 if (pfd[TO_CGI].revents) {
1136                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1137                         /* Have data from peer and can write to CGI */
1138                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1139                         /* Doesn't happen, we dont use nonblocking IO here
1140                          *if (count < 0 && errno == EAGAIN) {
1141                          *      ...
1142                          *} else */
1143                         if (count > 0) {
1144                                 hdr_ptr += count;
1145                                 hdr_cnt -= count;
1146                         } else {
1147                                 /* EOF/broken pipe to CGI, stop piping POST data */
1148                                 hdr_cnt = post_len = 0;
1149                         }
1150                 }
1151
1152                 if (pfd[0].revents) {
1153                         /* post_len > 0 && hdr_cnt == 0 here */
1154                         /* We expect data, prev data portion is eaten by CGI
1155                          * and there *is* data to read from the peer
1156                          * (POSTDATA) */
1157                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1158                         //count = safe_read(STDIN_FILENO, hdr_buf, count);
1159                         count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1160                         if (count > 0) {
1161                                 hdr_cnt = count;
1162                                 hdr_ptr = hdr_buf;
1163                                 post_len -= count;
1164                         } else {
1165                                 /* no more POST data can be read */
1166                                 post_len = 0;
1167                         }
1168                 }
1169
1170                 if (pfd[FROM_CGI].revents) {
1171                         /* There is something to read from CGI */
1172                         char *rbuf = iobuf;
1173
1174                         /* Are we still buffering CGI output? */
1175                         if (out_cnt >= 0) {
1176                                 /* HTTP_200[] has single "\r\n" at the end.
1177                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1178                                  * CGI scripts MUST send their own header terminated by
1179                                  * empty line, then data. That's why we have only one
1180                                  * <cr><lf> pair here. We will output "200 OK" line
1181                                  * if needed, but CGI still has to provide blank line
1182                                  * between header and body */
1183
1184                                 /* Must use safe_read, not full_read, because
1185                                  * CGI may output a few first bytes and then wait
1186                                  * for POSTDATA without closing stdout.
1187                                  * With full_read we may wait here forever. */
1188                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1189                                 if (count <= 0) {
1190                                         /* eof (or error) and there was no "HTTP",
1191                                          * so write it, then write received data */
1192                                         if (out_cnt) {
1193                                                 full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
1194                                                 full_write(STDOUT_FILENO, rbuf, out_cnt);
1195                                         }
1196                                         break; /* CGI stdout is closed, exiting */
1197                                 }
1198                                 out_cnt += count;
1199                                 count = 0;
1200                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1201                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1202                                         /* send "HTTP/1.0 " */
1203                                         if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
1204                                                 break;
1205                                         rbuf += 8; /* skip "Status: " */
1206                                         count = out_cnt - 8;
1207                                         out_cnt = -1; /* buffering off */
1208                                 } else if (out_cnt >= 4) {
1209                                         /* Did CGI add "HTTP"? */
1210                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1211                                                 /* there is no "HTTP", do it ourself */
1212                                                 if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1213                                                         break;
1214                                         }
1215                                         /* Commented out:
1216                                         if (!strstr(rbuf, "ontent-")) {
1217                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1218                                         }
1219                                          * Counter-example of valid CGI without Content-type:
1220                                          * echo -en "HTTP/1.0 302 Found\r\n"
1221                                          * echo -en "Location: http://www.busybox.net\r\n"
1222                                          * echo -en "\r\n"
1223                                          */
1224                                         count = out_cnt;
1225                                         out_cnt = -1; /* buffering off */
1226                                 }
1227                         } else {
1228                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1229                                 if (count <= 0)
1230                                         break;  /* eof (or error) */
1231                         }
1232                         if (full_write(STDOUT_FILENO, rbuf, count) != count)
1233                                 break;
1234                         if (DEBUG)
1235                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1236                 } /* if (pfd[FROM_CGI].revents) */
1237         } /* while (1) */
1238         log_and_exit();
1239 }
1240 #endif
1241
1242 #if ENABLE_FEATURE_HTTPD_CGI
1243
1244 static void setenv1(const char *name, const char *value)
1245 {
1246         setenv(name, value ? value : "", 1);
1247 }
1248
1249 /*
1250  * Spawn CGI script, forward CGI's stdin/out <=> network
1251  *
1252  * Environment variables are set up and the script is invoked with pipes
1253  * for stdin/stdout.  If a POST is being done the script is fed the POST
1254  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1255  *
1256  * Parameters:
1257  * const char *url              The requested URL (with leading /).
1258  * int post_len                 Length of the POST body.
1259  * const char *cookie           For set HTTP_COOKIE.
1260  * const char *content_type     For set CONTENT_TYPE.
1261  */
1262 static void send_cgi_and_exit(
1263                 const char *url,
1264                 const char *request,
1265                 int post_len,
1266                 const char *cookie,
1267                 const char *content_type) NORETURN;
1268 static void send_cgi_and_exit(
1269                 const char *url,
1270                 const char *request,
1271                 int post_len,
1272                 const char *cookie,
1273                 const char *content_type)
1274 {
1275         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1276         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1277         char *script;
1278         int pid;
1279
1280         /* Make a copy. NB: caller guarantees:
1281          * url[0] == '/', url[1] != '/' */
1282         url = xstrdup(url);
1283
1284         /*
1285          * We are mucking with environment _first_ and then vfork/exec,
1286          * this allows us to use vfork safely. Parent doesn't care about
1287          * these environment changes anyway.
1288          */
1289
1290         /* Check for [dirs/]script.cgi/PATH_INFO */
1291         script = (char*)url;
1292         while ((script = strchr(script + 1, '/')) != NULL) {
1293                 *script = '\0';
1294                 if (!is_directory(url + 1, 1, NULL)) {
1295                         /* not directory, found script.cgi/PATH_INFO */
1296                         *script = '/';
1297                         break;
1298                 }
1299                 *script = '/'; /* is directory, find next '/' */
1300         }
1301         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1302         setenv1("REQUEST_METHOD", request);
1303         if (g_query) {
1304                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1305         } else {
1306                 setenv1("REQUEST_URI", url);
1307         }
1308         if (script != NULL)
1309                 *script = '\0';         /* cut off /PATH_INFO */
1310
1311         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1312         if (home_httpd[0] == '/') {
1313                 char *fullpath = concat_path_file(home_httpd, url);
1314                 setenv1("SCRIPT_FILENAME", fullpath);
1315         }
1316         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1317         setenv1("SCRIPT_NAME", url);
1318         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1319          * QUERY_STRING: The information which follows the ? in the URL
1320          * which referenced this script. This is the query information.
1321          * It should not be decoded in any fashion. This variable
1322          * should always be set when there is query information,
1323          * regardless of command line decoding. */
1324         /* (Older versions of bbox seem to do some decoding) */
1325         setenv1("QUERY_STRING", g_query);
1326         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1327         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1328         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1329         /* Having _separate_ variables for IP and port defeats
1330          * the purpose of having socket abstraction. Which "port"
1331          * are you using on Unix domain socket?
1332          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1333          * Oh well... */
1334         {
1335                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1336                 char *cp = strrchr(p, ':');
1337                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1338                         cp = NULL;
1339                 if (cp) *cp = '\0'; /* delete :PORT */
1340                 setenv1("REMOTE_ADDR", p);
1341                 if (cp) {
1342                         *cp = ':';
1343 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1344                         setenv1("REMOTE_PORT", cp + 1);
1345 #endif
1346                 }
1347         }
1348         setenv1("HTTP_USER_AGENT", user_agent);
1349         if (http_accept)
1350                 setenv1("HTTP_ACCEPT", http_accept);
1351         if (http_accept_language)
1352                 setenv1("HTTP_ACCEPT_LANGUAGE", http_accept_language);
1353         if (post_len)
1354                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1355         if (cookie)
1356                 setenv1("HTTP_COOKIE", cookie);
1357         if (content_type)
1358                 setenv1("CONTENT_TYPE", content_type);
1359 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1360         if (remoteuser) {
1361                 setenv1("REMOTE_USER", remoteuser);
1362                 putenv((char*)"AUTH_TYPE=Basic");
1363         }
1364 #endif
1365         if (referer)
1366                 setenv1("HTTP_REFERER", referer);
1367         setenv1("HTTP_HOST", host); /* set to "" if NULL */
1368         /* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
1369          * just run "env SERVER_NAME=xyz httpd ..." instead */
1370
1371         xpiped_pair(fromCgi);
1372         xpiped_pair(toCgi);
1373
1374         pid = vfork();
1375         if (pid < 0) {
1376                 /* TODO: log perror? */
1377                 log_and_exit();
1378         }
1379
1380         if (!pid) {
1381                 /* Child process */
1382                 char *argv[3];
1383
1384                 xfunc_error_retval = 242;
1385
1386                 /* NB: close _first_, then move fds! */
1387                 close(toCgi.wr);
1388                 close(fromCgi.rd);
1389                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1390                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1391                 /* User seeing stderr output can be a security problem.
1392                  * If CGI really wants that, it can always do dup itself. */
1393                 /* dup2(1, 2); */
1394
1395                 /* Chdiring to script's dir */
1396                 script = strrchr(url, '/');
1397                 if (script != url) { /* paranoia */
1398                         *script = '\0';
1399                         if (chdir(url + 1) != 0) {
1400                                 bb_perror_msg("chdir(%s)", url + 1);
1401                                 goto error_execing_cgi;
1402                         }
1403                         // not needed: *script = '/';
1404                 }
1405                 script++;
1406
1407                 /* set argv[0] to name without path */
1408                 argv[0] = script;
1409                 argv[1] = NULL;
1410
1411 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1412                 {
1413                         char *suffix = strrchr(script, '.');
1414
1415                         if (suffix) {
1416                                 Htaccess *cur;
1417                                 for (cur = script_i; cur; cur = cur->next) {
1418                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1419                                                 /* found interpreter name */
1420                                                 argv[0] = cur->after_colon;
1421                                                 argv[1] = script;
1422                                                 argv[2] = NULL;
1423                                                 break;
1424                                         }
1425                                 }
1426                         }
1427                 }
1428 #endif
1429                 /* restore default signal dispositions for CGI process */
1430                 bb_signals(0
1431                         | (1 << SIGCHLD)
1432                         | (1 << SIGPIPE)
1433                         | (1 << SIGHUP)
1434                         , SIG_DFL);
1435
1436                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1437                  * without any dir components and will only match a file
1438                  * in the current directory */
1439                 execv(argv[0], argv);
1440                 if (verbose)
1441                         bb_perror_msg("can't execute '%s'", argv[0]);
1442  error_execing_cgi:
1443                 /* send to stdout
1444                  * (we are CGI here, our stdout is pumped to the net) */
1445                 send_headers_and_exit(HTTP_NOT_FOUND);
1446         } /* end child */
1447
1448         /* Parent process */
1449
1450         /* Restore variables possibly changed by child */
1451         xfunc_error_retval = 0;
1452
1453         /* Pump data */
1454         close(fromCgi.wr);
1455         close(toCgi.rd);
1456         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1457 }
1458
1459 #endif          /* FEATURE_HTTPD_CGI */
1460
1461 /*
1462  * Send a file response to a HTTP request, and exit
1463  *
1464  * Parameters:
1465  * const char *url  The requested URL (with leading /).
1466  * what             What to send (headers/body/both).
1467  */
1468 static NOINLINE void send_file_and_exit(const char *url, int what)
1469 {
1470         char *suffix;
1471         int fd;
1472         ssize_t count;
1473
1474         if (content_gzip) {
1475                 /* does <url>.gz exist? Then use it instead */
1476                 char *gzurl = xasprintf("%s.gz", url);
1477                 fd = open(gzurl, O_RDONLY);
1478                 free(gzurl);
1479                 if (fd != -1) {
1480                         struct stat sb;
1481                         fstat(fd, &sb);
1482                         file_size = sb.st_size;
1483                         last_mod = sb.st_mtime;
1484                 } else {
1485                         IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
1486                         fd = open(url, O_RDONLY);
1487                 }
1488         } else {
1489                 fd = open(url, O_RDONLY);
1490         }
1491         if (fd < 0) {
1492                 if (DEBUG)
1493                         bb_perror_msg("can't open '%s'", url);
1494                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1495                  * IOW: it is unsafe to call send_headers_and_exit
1496                  * if what is SEND_BODY! Can recurse! */
1497                 if (what != SEND_BODY)
1498                         send_headers_and_exit(HTTP_NOT_FOUND);
1499                 log_and_exit();
1500         }
1501         /* If you want to know about EPIPE below
1502          * (happens if you abort downloads from local httpd): */
1503         signal(SIGPIPE, SIG_IGN);
1504
1505         /* If not found, default is "application/octet-stream" */
1506         found_mime_type = "application/octet-stream";
1507         suffix = strrchr(url, '.');
1508         if (suffix) {
1509                 static const char suffixTable[] ALIGN1 =
1510                         /* Shorter suffix must be first:
1511                          * ".html.htm" will fail for ".htm"
1512                          */
1513                         ".txt.h.c.cc.cpp\0" "text/plain\0"
1514                         /* .htm line must be after .h line */
1515                         ".htm.html\0" "text/html\0"
1516                         ".jpg.jpeg\0" "image/jpeg\0"
1517                         ".gif\0"      "image/gif\0"
1518                         ".png\0"      "image/png\0"
1519                         /* .css line must be after .c line */
1520                         ".css\0"      "text/css\0"
1521                         ".wav\0"      "audio/wav\0"
1522                         ".avi\0"      "video/x-msvideo\0"
1523                         ".qt.mov\0"   "video/quicktime\0"
1524                         ".mpe.mpeg\0" "video/mpeg\0"
1525                         ".mid.midi\0" "audio/midi\0"
1526                         ".mp3\0"      "audio/mpeg\0"
1527 #if 0  /* unpopular */
1528                         ".au\0"       "audio/basic\0"
1529                         ".pac\0"      "application/x-ns-proxy-autoconfig\0"
1530                         ".vrml.wrl\0" "model/vrml\0"
1531 #endif
1532                         /* compiler adds another "\0" here */
1533                 ;
1534                 Htaccess *cur;
1535
1536                 /* Examine built-in table */
1537                 const char *table = suffixTable;
1538                 const char *table_next;
1539                 for (; *table; table = table_next) {
1540                         const char *try_suffix;
1541                         const char *mime_type;
1542                         mime_type  = table + strlen(table) + 1;
1543                         table_next = mime_type + strlen(mime_type) + 1;
1544                         try_suffix = strstr(table, suffix);
1545                         if (!try_suffix)
1546                                 continue;
1547                         try_suffix += strlen(suffix);
1548                         if (*try_suffix == '\0' || *try_suffix == '.') {
1549                                 found_mime_type = mime_type;
1550                                 break;
1551                         }
1552                         /* Example: strstr(table, ".av") != NULL, but it
1553                          * does not match ".avi" after all and we end up here.
1554                          * The table is arranged so that in this case we know
1555                          * that it can't match anything in the following lines,
1556                          * and we stop the search: */
1557                         break;
1558                 }
1559                 /* ...then user's table */
1560                 for (cur = mime_a; cur; cur = cur->next) {
1561                         if (strcmp(cur->before_colon, suffix) == 0) {
1562                                 found_mime_type = cur->after_colon;
1563                                 break;
1564                         }
1565                 }
1566         }
1567
1568         if (DEBUG)
1569                 bb_error_msg("sending file '%s' content-type: %s",
1570                         url, found_mime_type);
1571
1572 #if ENABLE_FEATURE_HTTPD_RANGES
1573         if (what == SEND_BODY /* err pages and ranges don't mix */
1574          || content_gzip /* we are sending compressed page: can't do ranges */  ///why?
1575         ) {
1576                 range_start = 0;
1577         }
1578         range_len = MAXINT(off_t);
1579         if (range_start) {
1580                 if (!range_end) {
1581                         range_end = file_size - 1;
1582                 }
1583                 if (range_end < range_start
1584                  || lseek(fd, range_start, SEEK_SET) != range_start
1585                 ) {
1586                         lseek(fd, 0, SEEK_SET);
1587                         range_start = 0;
1588                 } else {
1589                         range_len = range_end - range_start + 1;
1590                         send_headers(HTTP_PARTIAL_CONTENT);
1591                         what = SEND_BODY;
1592                 }
1593         }
1594 #endif
1595         if (what & SEND_HEADERS)
1596                 send_headers(HTTP_OK);
1597 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1598         {
1599                 off_t offset = range_start;
1600                 while (1) {
1601                         /* sz is rounded down to 64k */
1602                         ssize_t sz = MAXINT(ssize_t) - 0xffff;
1603                         IF_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1604                         count = sendfile(STDOUT_FILENO, fd, &offset, sz);
1605                         if (count < 0) {
1606                                 if (offset == range_start)
1607                                         break; /* fall back to read/write loop */
1608                                 goto fin;
1609                         }
1610                         IF_FEATURE_HTTPD_RANGES(range_len -= sz;)
1611                         if (count == 0 || range_len == 0)
1612                                 log_and_exit();
1613                 }
1614         }
1615 #endif
1616         while ((count = safe_read(fd, iobuf, IOBUF_SIZE)) > 0) {
1617                 ssize_t n;
1618                 IF_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1619                 n = full_write(STDOUT_FILENO, iobuf, count);
1620                 if (count != n)
1621                         break;
1622                 IF_FEATURE_HTTPD_RANGES(range_len -= count;)
1623                 if (range_len == 0)
1624                         break;
1625         }
1626         if (count < 0) {
1627  IF_FEATURE_HTTPD_USE_SENDFILE(fin:)
1628                 if (verbose > 1)
1629                         bb_perror_msg("error");
1630         }
1631         log_and_exit();
1632 }
1633
1634 static int checkPermIP(void)
1635 {
1636         Htaccess_IP *cur;
1637
1638         for (cur = ip_a_d; cur; cur = cur->next) {
1639 #if DEBUG
1640                 fprintf(stderr,
1641                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1642                         rmt_ip_str,
1643                         (unsigned char)(cur->ip >> 24),
1644                         (unsigned char)(cur->ip >> 16),
1645                         (unsigned char)(cur->ip >> 8),
1646                         (unsigned char)(cur->ip),
1647                         (unsigned char)(cur->mask >> 24),
1648                         (unsigned char)(cur->mask >> 16),
1649                         (unsigned char)(cur->mask >> 8),
1650                         (unsigned char)(cur->mask)
1651                 );
1652 #endif
1653                 if ((rmt_ip & cur->mask) == cur->ip)
1654                         return (cur->allow_deny == 'A'); /* A -> 1 */
1655         }
1656
1657         return !flg_deny_all; /* depends on whether we saw "D:*" */
1658 }
1659
1660 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1661 /*
1662  * Config file entries are of the form "/<path>:<user>:<passwd>".
1663  * If config file has no prefix match for path, access is allowed.
1664  *
1665  * path                 The file path
1666  * user_and_passwd      "user:passwd" to validate
1667  *
1668  * Returns 1 if user_and_passwd is OK.
1669  */
1670 static int check_user_passwd(const char *path, const char *user_and_passwd)
1671 {
1672         Htaccess *cur;
1673         const char *prev = NULL;
1674
1675         for (cur = g_auth; cur; cur = cur->next) {
1676                 const char *dir_prefix;
1677                 size_t len;
1678
1679                 dir_prefix = cur->before_colon;
1680
1681                 /* WHY? */
1682                 /* If already saw a match, don't accept other different matches */
1683                 if (prev && strcmp(prev, dir_prefix) != 0)
1684                         continue;
1685
1686                 if (DEBUG)
1687                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
1688
1689                 /* If it's not a prefix match, continue searching */
1690                 len = strlen(dir_prefix);
1691                 if (len != 1 /* dir_prefix "/" matches all, don't need to check */
1692                  && (strncmp(dir_prefix, path, len) != 0
1693                     || (path[len] != '/' && path[len] != '\0'))
1694                 ) {
1695                         continue;
1696                 }
1697
1698                 /* Path match found */
1699                 prev = dir_prefix;
1700
1701                 if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1702                         char *md5_passwd;
1703
1704                         md5_passwd = strchr(cur->after_colon, ':');
1705                         if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
1706                          && md5_passwd[3] == '$' && md5_passwd[4]
1707                         ) {
1708                                 char *encrypted;
1709                                 int r, user_len_p1;
1710
1711                                 md5_passwd++;
1712                                 user_len_p1 = md5_passwd - cur->after_colon;
1713                                 /* comparing "user:" */
1714                                 if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
1715                                         continue;
1716                                 }
1717
1718                                 encrypted = pw_encrypt(
1719                                         user_and_passwd + user_len_p1 /* cleartext pwd from user */,
1720                                         md5_passwd /*salt */, 1 /* cleanup */);
1721                                 r = strcmp(encrypted, md5_passwd);
1722                                 free(encrypted);
1723                                 if (r == 0)
1724                                         goto set_remoteuser_var; /* Ok */
1725                                 continue;
1726                         }
1727                 }
1728
1729                 /* Comparing plaintext "user:pass" in one go */
1730                 if (strcmp(cur->after_colon, user_and_passwd) == 0) {
1731  set_remoteuser_var:
1732                         remoteuser = xstrndup(user_and_passwd,
1733                                         strchrnul(user_and_passwd, ':') - user_and_passwd);
1734                         return 1; /* Ok */
1735                 }
1736         } /* for */
1737
1738         /* 0(bad) if prev is set: matches were found but passwd was wrong */
1739         return (prev == NULL);
1740 }
1741 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1742
1743 #if ENABLE_FEATURE_HTTPD_PROXY
1744 static Htaccess_Proxy *find_proxy_entry(const char *url)
1745 {
1746         Htaccess_Proxy *p;
1747         for (p = proxy; p; p = p->next) {
1748                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1749                         return p;
1750         }
1751         return NULL;
1752 }
1753 #endif
1754
1755 /*
1756  * Handle timeouts
1757  */
1758 static void send_REQUEST_TIMEOUT_and_exit(int sig) NORETURN;
1759 static void send_REQUEST_TIMEOUT_and_exit(int sig UNUSED_PARAM)
1760 {
1761         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1762 }
1763
1764 /*
1765  * Handle an incoming http request and exit.
1766  */
1767 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
1768 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1769 {
1770         static const char request_GET[] ALIGN1 = "GET";
1771         struct stat sb;
1772         char *urlcopy;
1773         char *urlp;
1774         char *tptr;
1775 #if ENABLE_FEATURE_HTTPD_CGI
1776         static const char request_HEAD[] ALIGN1 = "HEAD";
1777         const char *prequest;
1778         char *cookie = NULL;
1779         char *content_type = NULL;
1780         unsigned long length = 0;
1781 #elif ENABLE_FEATURE_HTTPD_PROXY
1782 #define prequest request_GET
1783         unsigned long length = 0;
1784 #endif
1785 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1786         smallint authorized = -1;
1787 #endif
1788         smallint ip_allowed;
1789         char http_major_version;
1790 #if ENABLE_FEATURE_HTTPD_PROXY
1791         char http_minor_version;
1792         char *header_buf = header_buf; /* for gcc */
1793         char *header_ptr = header_ptr;
1794         Htaccess_Proxy *proxy_entry;
1795 #endif
1796
1797         /* Allocation of iobuf is postponed until now
1798          * (IOW, server process doesn't need to waste 8k) */
1799         iobuf = xmalloc(IOBUF_SIZE);
1800
1801         rmt_ip = 0;
1802         if (fromAddr->u.sa.sa_family == AF_INET) {
1803                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1804         }
1805 #if ENABLE_FEATURE_IPV6
1806         if (fromAddr->u.sa.sa_family == AF_INET6
1807          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1808          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1809          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1810                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1811 #endif
1812         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1813                 /* NB: can be NULL (user runs httpd -i by hand?) */
1814                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1815         }
1816         if (verbose) {
1817                 /* this trick makes -v logging much simpler */
1818                 if (rmt_ip_str)
1819                         applet_name = rmt_ip_str;
1820                 if (verbose > 2)
1821                         bb_error_msg("connected");
1822         }
1823
1824         /* Install timeout handler. get_line() needs it. */
1825         signal(SIGALRM, send_REQUEST_TIMEOUT_and_exit);
1826
1827         if (!get_line()) /* EOF or error or empty line */
1828                 send_headers_and_exit(HTTP_BAD_REQUEST);
1829
1830         /* Determine type of request (GET/POST) */
1831         urlp = strpbrk(iobuf, " \t");
1832         if (urlp == NULL)
1833                 send_headers_and_exit(HTTP_BAD_REQUEST);
1834         *urlp++ = '\0';
1835 #if ENABLE_FEATURE_HTTPD_CGI
1836         prequest = request_GET;
1837         if (strcasecmp(iobuf, prequest) != 0) {
1838                 prequest = request_HEAD;
1839                 if (strcasecmp(iobuf, prequest) != 0) {
1840                         prequest = "POST";
1841                         if (strcasecmp(iobuf, prequest) != 0)
1842                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1843                 }
1844         }
1845 #else
1846         if (strcasecmp(iobuf, request_GET) != 0)
1847                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1848 #endif
1849         urlp = skip_whitespace(urlp);
1850         if (urlp[0] != '/')
1851                 send_headers_and_exit(HTTP_BAD_REQUEST);
1852
1853         /* Find end of URL and parse HTTP version, if any */
1854         http_major_version = '0';
1855         IF_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1856         tptr = strchrnul(urlp, ' ');
1857         /* Is it " HTTP/"? */
1858         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1859                 http_major_version = tptr[6];
1860                 IF_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1861         }
1862         *tptr = '\0';
1863
1864         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1865         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1866         /*if (urlcopy == NULL)
1867          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1868         strcpy(urlcopy, urlp);
1869         /* NB: urlcopy ptr is never changed after this */
1870
1871         /* Extract url args if present */
1872         g_query = NULL;
1873         tptr = strchr(urlcopy, '?');
1874         if (tptr) {
1875                 *tptr++ = '\0';
1876                 g_query = tptr;
1877         }
1878
1879         /* Decode URL escape sequences */
1880         tptr = percent_decode_in_place(urlcopy, /*strict:*/ 1);
1881         if (tptr == NULL)
1882                 send_headers_and_exit(HTTP_BAD_REQUEST);
1883         if (tptr == urlcopy + 1) {
1884                 /* '/' or NUL is encoded */
1885                 send_headers_and_exit(HTTP_NOT_FOUND);
1886         }
1887
1888         /* Canonicalize path */
1889         /* Algorithm stolen from libbb bb_simplify_path(),
1890          * but don't strdup, retain trailing slash, protect root */
1891         urlp = tptr = urlcopy;
1892         do {
1893                 if (*urlp == '/') {
1894                         /* skip duplicate (or initial) slash */
1895                         if (*tptr == '/') {
1896                                 continue;
1897                         }
1898                         if (*tptr == '.') {
1899                                 /* skip extra "/./" */
1900                                 if (tptr[1] == '/' || !tptr[1]) {
1901                                         continue;
1902                                 }
1903                                 /* "..": be careful */
1904                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1905                                         ++tptr;
1906                                         if (urlp == urlcopy) /* protect root */
1907                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1908                                         while (*--urlp != '/') /* omit previous dir */;
1909                                                 continue;
1910                                 }
1911                         }
1912                 }
1913                 *++urlp = *tptr;
1914         } while (*++tptr);
1915         *++urlp = '\0';       /* terminate after last character */
1916
1917         /* If URL is a directory, add '/' */
1918         if (urlp[-1] != '/') {
1919                 if (is_directory(urlcopy + 1, 1, NULL)) {
1920                         found_moved_temporarily = urlcopy;
1921                 }
1922         }
1923
1924         /* Log it */
1925         if (verbose > 1)
1926                 bb_error_msg("url:%s", urlcopy);
1927
1928         tptr = urlcopy;
1929         ip_allowed = checkPermIP();
1930         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1931                 /* have path1/path2 */
1932                 *tptr = '\0';
1933                 if (is_directory(urlcopy + 1, 1, NULL)) {
1934                         /* may have subdir config */
1935                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1936                         ip_allowed = checkPermIP();
1937                 }
1938                 *tptr = '/';
1939         }
1940
1941 #if ENABLE_FEATURE_HTTPD_PROXY
1942         proxy_entry = find_proxy_entry(urlcopy);
1943         if (proxy_entry)
1944                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1945 #endif
1946
1947         if (http_major_version >= '0') {
1948                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1949
1950                 /* Read until blank line */
1951                 while (1) {
1952                         if (!get_line())
1953                                 break; /* EOF or error or empty line */
1954                         if (DEBUG)
1955                                 bb_error_msg("header: '%s'", iobuf);
1956
1957 #if ENABLE_FEATURE_HTTPD_PROXY
1958                         /* We need 2 more bytes for yet another "\r\n" -
1959                          * see near fdprintf(proxy_fd...) further below */
1960                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1961                                 int len = strlen(iobuf);
1962                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1963                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1964                                 memcpy(header_ptr, iobuf, len);
1965                                 header_ptr += len;
1966                                 header_ptr[0] = '\r';
1967                                 header_ptr[1] = '\n';
1968                                 header_ptr += 2;
1969                         }
1970 #endif
1971
1972 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1973                         /* Try and do our best to parse more lines */
1974                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1975                                 /* extra read only for POST */
1976                                 if (prequest != request_GET
1977 # if ENABLE_FEATURE_HTTPD_CGI
1978                                  && prequest != request_HEAD
1979 # endif
1980                                 ) {
1981                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1982                                         if (!tptr[0])
1983                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1984                                         /* not using strtoul: it ignores leading minus! */
1985                                         length = bb_strtou(tptr, NULL, 10);
1986                                         /* length is "ulong", but we need to pass it to int later */
1987                                         if (errno || length > INT_MAX)
1988                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1989                                 }
1990                         }
1991 #endif
1992 #if ENABLE_FEATURE_HTTPD_CGI
1993                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
1994                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
1995                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
1996                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
1997                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
1998                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
1999                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2000                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2001                         } else if (STRNCASECMP(iobuf, "Host:") == 0) {
2002                                 host = xstrdup(skip_whitespace(iobuf + sizeof("Host:")-1));
2003                         } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
2004                                 http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
2005                         } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
2006                                 http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
2007                         }
2008 #endif
2009 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2010                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2011                                 /* We only allow Basic credentials.
2012                                  * It shows up as "Authorization: Basic <user>:<passwd>" where
2013                                  * "<user>:<passwd>" is base64 encoded.
2014                                  */
2015                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2016                                 if (STRNCASECMP(tptr, "Basic") != 0)
2017                                         continue;
2018                                 tptr += sizeof("Basic")-1;
2019                                 /* decodeBase64() skips whitespace itself */
2020                                 decodeBase64(tptr);
2021                                 authorized = check_user_passwd(urlcopy, tptr);
2022                         }
2023 #endif
2024 #if ENABLE_FEATURE_HTTPD_RANGES
2025                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2026                                 /* We know only bytes=NNN-[MMM] */
2027                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2028                                 if (strncmp(s, "bytes=", 6) == 0) {
2029                                         s += sizeof("bytes=")-1;
2030                                         range_start = BB_STRTOOFF(s, &s, 10);
2031                                         if (s[0] != '-' || range_start < 0) {
2032                                                 range_start = 0;
2033                                         } else if (s[1]) {
2034                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2035                                                 if (errno || range_end < range_start)
2036                                                         range_start = 0;
2037                                         }
2038                                 }
2039                         }
2040 #endif
2041 #if ENABLE_FEATURE_HTTPD_GZIP
2042                         if (STRNCASECMP(iobuf, "Accept-Encoding:") == 0) {
2043                                 /* Note: we do not support "gzip;q=0"
2044                                  * method of _disabling_ gzip
2045                                  * delivery. No one uses that, though */
2046                                 const char *s = strstr(iobuf, "gzip");
2047                                 if (s) {
2048                                         // want more thorough checks?
2049                                         //if (s[-1] == ' '
2050                                         // || s[-1] == ','
2051                                         // || s[-1] == ':'
2052                                         //) {
2053                                                 content_gzip = 1;
2054                                         //}
2055                                 }
2056                         }
2057 #endif
2058                 } /* while extra header reading */
2059         }
2060
2061         /* We are done reading headers, disable peer timeout */
2062         alarm(0);
2063
2064         if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0 || !ip_allowed) {
2065                 /* protect listing [/path]/httpd.conf or IP deny */
2066                 send_headers_and_exit(HTTP_FORBIDDEN);
2067         }
2068
2069 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2070         /* Case: no "Authorization:" was seen, but page does require passwd.
2071          * Check that with dummy user:pass */
2072         if (authorized < 0)
2073                 authorized = check_user_passwd(urlcopy, ":");
2074         if (!authorized)
2075                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2076 #endif
2077
2078         if (found_moved_temporarily) {
2079                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2080         }
2081
2082 #if ENABLE_FEATURE_HTTPD_PROXY
2083         if (proxy_entry != NULL) {
2084                 int proxy_fd;
2085                 len_and_sockaddr *lsa;
2086
2087                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2088                 if (proxy_fd < 0)
2089                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2090                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2091                 if (lsa == NULL)
2092                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2093                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2094                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2095                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2096                                 prequest, /* GET or POST */
2097                                 proxy_entry->url_to, /* url part 1 */
2098                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2099                                 (g_query ? "?" : ""), /* "?" (maybe) */
2100                                 (g_query ? g_query : ""), /* query string (maybe) */
2101                                 http_major_version, http_minor_version);
2102                 header_ptr[0] = '\r';
2103                 header_ptr[1] = '\n';
2104                 header_ptr += 2;
2105                 write(proxy_fd, header_buf, header_ptr - header_buf);
2106                 free(header_buf); /* on the order of 8k, free it */
2107                 cgi_io_loop_and_exit(proxy_fd, 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                 if (n < 0)
2187                         continue;
2188
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                 if (n < 0)
2230                         continue;
2231
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(percent_decode_in_place(url_for_decode, /*strict:*/ 0), 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);
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 }