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 /*
 824  * Given a URL encoded string, convert it to plain ascii.
 825  * Since decoding always makes strings smaller, the decode is done in-place.
 826  * Thus, callers should xstrdup() the argument if they do not want the
 827  * argument modified.  The return is the original pointer, allowing this
 828  * function to be easily used as arguments to other functions.
 829  *
 830  * string    The first string to decode.
 831  * option_d  1 if called for httpd -d
 832  *
 833  * Returns a pointer to the decoded string (same as input).
 834  */
 835 static unsigned hex_to_bin(unsigned char c)
 836 {
 837         unsigned v;
 838
 839         v = c - '0';
 840         if (v <= 9)
 841                 return v;
 842         /* c | 0x20: letters to lower case, non-letters
 843          * to (potentially different) non-letters */
 844         v = (unsigned)(c | 0x20) - 'a';
 845         if (v <= 5)
 846                 return v + 10;
 847         return ~0;
 848 /* For testing:
 849 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
 850 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 851 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 852 */
 853 }
 854 static char *decodeString(char *orig, int option_d)
 855 {
 856         /* note that decoded string is always shorter than original */
 857         char *string = orig;
 858         char *ptr = string;
 859         char c;
 860
 861         while ((c = *ptr++) != '\0') {
 862                 unsigned v;
 863
 864                 if (option_d && c == '+') {
 865                         *string++ = ' ';
 866                         continue;
 867                 }
 868                 if (c != '%') {
 869                         *string++ = c;
 870                         continue;
 871                 }
 872                 v = hex_to_bin(ptr[0]);
 873                 if (v > 15) {
 874  bad_hex:
 875                         if (!option_d)
 876                                 return NULL;
 877                         *string++ = '%';
 878                         continue;
 879                 }
 880                 v = (v * 16) | hex_to_bin(ptr[1]);
 881                 if (v > 255)
 882                         goto bad_hex;
 883                 if (!option_d && (v == '/' || v == '\0')) {
 884                         /* caller takes it as indication of invalid
 885                          * (dangerous wrt exploits) chars */
 886                         return orig + 1;
 887                 }
 888                 *string++ = v;
 889                 ptr += 2;
 890         }
 891         *string = '\0';
 892         return orig;
 893 }
 894
 895 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 896 /*
 897  * Decode a base64 data stream as per rfc1521.
 898  * Note that the rfc states that non base64 chars are to be ignored.
 899  * Since the decode always results in a shorter size than the input,
 900  * it is OK to pass the input arg as an output arg.
 901  * Parameter: a pointer to a base64 encoded string.
 902  * Decoded data is stored in-place.
 903  */
 904 static void decodeBase64(char *Data)
 905 {
 906         const unsigned char *in = (const unsigned char *)Data;
 907         /* The decoded size will be at most 3/4 the size of the encoded */
 908         unsigned ch = 0;
 909         int i = 0;
 910
 911         while (*in) {
 912                 int t = *in++;
 913
 914                 if (t >= '0' && t <= '9')
 915                         t = t - '0' + 52;
 916                 else if (t >= 'A' && t <= 'Z')
 917                         t = t - 'A';
 918                 else if (t >= 'a' && t <= 'z')
 919                         t = t - 'a' + 26;
 920                 else if (t == '+')
 921                         t = 62;
 922                 else if (t == '/')
 923                         t = 63;
 924                 else if (t == '=')
 925                         t = 0;
 926                 else
 927                         continue;
 928
 929                 ch = (ch << 6) | t;
 930                 i++;
 931                 if (i == 4) {
 932                         *Data++ = (char) (ch >> 16);
 933                         *Data++ = (char) (ch >> 8);
 934                         *Data++ = (char) ch;
 935                         i = 0;
 936                 }
 937         }
 938         *Data = '\0';
 939 }
 940 #endif
 941
 942 /*
 943  * Create a listen server socket on the designated port.
 944  */
 945 static int openServer(void)
 946 {
 947         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 948         if (!errno && n && n <= 0xffff)
 949                 n = create_and_bind_stream_or_die(NULL, n);
 950         else
 951                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 952         xlisten(n, 9);
 953         return n;
 954 }
 955
 956 /*
 957  * Log the connection closure and exit.
 958  */
 959 static void log_and_exit(void) NORETURN;
 960 static void log_and_exit(void)
 961 {
 962         /* Paranoia. IE said to be buggy. It may send some extra data
 963          * or be confused by us just exiting without SHUT_WR. Oh well. */
 964         shutdown(1, SHUT_WR);
 965         /* Why??
 966         (this also messes up stdin when user runs httpd -i from terminal)
 967         ndelay_on(0);
 968         while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
 969                 continue;
 970         */
 971
 972         if (verbose > 2)
 973                 bb_error_msg("closed");
 974         _exit(xfunc_error_retval);
 975 }
 976
 977 /*
 978  * Create and send HTTP response headers.
 979  * The arguments are combined and sent as one write operation.  Note that
 980  * IE will puke big-time if the headers are not sent in one packet and the
 981  * second packet is delayed for any reason.
 982  * responseNum - the result code to send.
 983  */
 984 static void send_headers(int responseNum)
 985 {
 986         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 987
 988         const char *responseString = "";
 989         const char *infoString = NULL;
 990         const char *mime_type;
 991 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 992         const char *error_page = NULL;
 993 #endif
 994         unsigned i;
 995         time_t timer = time(NULL);
 996         char tmp_str[80];
 997         int len;
 998
 999         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
1000                 if (http_response_type[i] == responseNum) {
1001                         responseString = http_response[i].name;
1002                         infoString = http_response[i].info;
1003 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1004                         error_page = http_error_page[i];
1005 #endif
1006                         break;
1007                 }
1008         }
1009         /* error message is HTML */
1010         mime_type = responseNum == HTTP_OK ?
1011                                 found_mime_type : "text/html";
1012
1013         if (verbose)
1014                 bb_error_msg("response:%u", responseNum);
1015
1016         /* emit the current date */
1017         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
1018         len = sprintf(iobuf,
1019                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
1020                         "Date: %s\r\nConnection: close\r\n",
1021                         responseNum, responseString, mime_type, tmp_str);
1022
1023 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1024         if (responseNum == HTTP_UNAUTHORIZED) {
1025                 len += sprintf(iobuf + len,
1026                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
1027                                 g_realm);
1028         }
1029 #endif
1030         if (responseNum == HTTP_MOVED_TEMPORARILY) {
1031                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
1032                                 found_moved_temporarily,
1033                                 (g_query ? "?" : ""),
1034                                 (g_query ? g_query : ""));
1035         }
1036
1037 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1038         if (error_page && access(error_page, R_OK) == 0) {
1039                 strcat(iobuf, "\r\n");
1040                 len += 2;
1041
1042                 if (DEBUG)
1043                         fprintf(stderr, "headers: '%s'\n", iobuf);
1044                 full_write(STDOUT_FILENO, iobuf, len);
1045                 if (DEBUG)
1046                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1047                 return send_file_and_exit(error_page, SEND_BODY);
1048         }
1049 #endif
1050
1051         if (file_size != -1) {    /* file */
1052                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1053 #if ENABLE_FEATURE_HTTPD_RANGES
1054                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1055                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"u-%"OFF_FMT"u/%"OFF_FMT"u\r\n",
1056                                         range_start,
1057                                         range_end,
1058                                         file_size);
1059                         file_size = range_end - range_start + 1;
1060                 }
1061 #endif
1062                 len += sprintf(iobuf + len,
1063 #if ENABLE_FEATURE_HTTPD_RANGES
1064                         "Accept-Ranges: bytes\r\n"
1065 #endif
1066                         "Last-Modified: %s\r\n%s %"OFF_FMT"u\r\n",
1067                                 tmp_str,
1068                                 content_gzip ? "Transfer-length:" : "Content-length:",
1069                                 file_size
1070                 );
1071         }
1072
1073         if (content_gzip)
1074                 len += sprintf(iobuf + len, "Content-Encoding: gzip\r\n");
1075
1076         iobuf[len++] = '\r';
1077         iobuf[len++] = '\n';
1078         if (infoString) {
1079                 len += sprintf(iobuf + len,
1080                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1081                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1082                                 responseNum, responseString,
1083                                 responseNum, responseString, infoString);
1084         }
1085         if (DEBUG)
1086                 fprintf(stderr, "headers: '%s'\n", iobuf);
1087         if (full_write(STDOUT_FILENO, iobuf, len) != len) {
1088                 if (verbose > 1)
1089                         bb_perror_msg("error");
1090                 log_and_exit();
1091         }
1092 }
1093
1094 static void send_headers_and_exit(int responseNum) NORETURN;
1095 static void send_headers_and_exit(int responseNum)
1096 {
1097         IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
1098         send_headers(responseNum);
1099         log_and_exit();
1100 }
1101
1102 /*
1103  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1104  * '\n' is replaced with NUL.
1105  * Return number of characters read or 0 if nothing is read
1106  * ('\r' and '\n' are not counted).
1107  * Data is returned in iobuf.
1108  */
1109 static int get_line(void)
1110 {
1111         int count = 0;
1112         char c;
1113
1114         alarm(HEADER_READ_TIMEOUT);
1115         while (1) {
1116                 if (hdr_cnt <= 0) {
1117                         hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1118                         if (hdr_cnt <= 0)
1119                                 break;
1120                         hdr_ptr = hdr_buf;
1121                 }
1122                 iobuf[count] = c = *hdr_ptr++;
1123                 hdr_cnt--;
1124
1125                 if (c == '\r')
1126                         continue;
1127                 if (c == '\n') {
1128                         iobuf[count] = '\0';
1129                         break;
1130                 }
1131                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1132                         count++;
1133         }
1134         return count;
1135 }
1136
1137 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1138
1139 /* gcc 4.2.1 fares better with NOINLINE */
1140 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
1141 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1142 {
1143         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1144         struct pollfd pfd[3];
1145         int out_cnt; /* we buffer a bit of initial CGI output */
1146         int count;
1147
1148         /* iobuf is used for CGI -> network data,
1149          * hdr_buf is for network -> CGI data (POSTDATA) */
1150
1151         /* If CGI dies, we still want to correctly finish reading its output
1152          * and send it to the peer. So please no SIGPIPEs! */
1153         signal(SIGPIPE, SIG_IGN);
1154
1155         // We inconsistently handle a case when more POSTDATA from network
1156         // is coming than we expected. We may give *some part* of that
1157         // extra data to CGI.
1158
1159         //if (hdr_cnt > post_len) {
1160         //      /* We got more POSTDATA from network than we expected */
1161         //      hdr_cnt = post_len;
1162         //}
1163         post_len -= hdr_cnt;
1164         /* post_len - number of POST bytes not yet read from network */
1165
1166         /* NB: breaking out of this loop jumps to log_and_exit() */
1167         out_cnt = 0;
1168         while (1) {
1169                 memset(pfd, 0, sizeof(pfd));
1170
1171                 pfd[FROM_CGI].fd = fromCgi_rd;
1172                 pfd[FROM_CGI].events = POLLIN;
1173
1174                 if (toCgi_wr) {
1175                         pfd[TO_CGI].fd = toCgi_wr;
1176                         if (hdr_cnt > 0) {
1177                                 pfd[TO_CGI].events = POLLOUT;
1178                         } else if (post_len > 0) {
1179                                 pfd[0].events = POLLIN;
1180                         } else {
1181                                 /* post_len <= 0 && hdr_cnt <= 0:
1182                                  * no more POST data to CGI,
1183                                  * let CGI see EOF on CGI's stdin */
1184                                 if (toCgi_wr != fromCgi_rd)
1185                                         close(toCgi_wr);
1186                                 toCgi_wr = 0;
1187                         }
1188                 }
1189
1190                 /* Now wait on the set of sockets */
1191                 count = safe_poll(pfd, toCgi_wr ? TO_CGI+1 : FROM_CGI+1, -1);
1192                 if (count <= 0) {
1193 #if 0
1194                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1195                                 /* Weird. CGI didn't exit and no fd's
1196                                  * are ready, yet poll returned?! */
1197                                 continue;
1198                         }
1199                         if (DEBUG && WIFEXITED(status))
1200                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1201                         if (DEBUG && WIFSIGNALED(status))
1202                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1203 #endif
1204                         break;
1205                 }
1206
1207                 if (pfd[TO_CGI].revents) {
1208                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1209                         /* Have data from peer and can write to CGI */
1210                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1211                         /* Doesn't happen, we dont use nonblocking IO here
1212                          *if (count < 0 && errno == EAGAIN) {
1213                          *      ...
1214                          *} else */
1215                         if (count > 0) {
1216                                 hdr_ptr += count;
1217                                 hdr_cnt -= count;
1218                         } else {
1219                                 /* EOF/broken pipe to CGI, stop piping POST data */
1220                                 hdr_cnt = post_len = 0;
1221                         }
1222                 }
1223
1224                 if (pfd[0].revents) {
1225                         /* post_len > 0 && hdr_cnt == 0 here */
1226                         /* We expect data, prev data portion is eaten by CGI
1227                          * and there *is* data to read from the peer
1228                          * (POSTDATA) */
1229                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1230                         //count = safe_read(STDIN_FILENO, hdr_buf, count);
1231                         count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1232                         if (count > 0) {
1233                                 hdr_cnt = count;
1234                                 hdr_ptr = hdr_buf;
1235                                 post_len -= count;
1236                         } else {
1237                                 /* no more POST data can be read */
1238                                 post_len = 0;
1239                         }
1240                 }
1241
1242                 if (pfd[FROM_CGI].revents) {
1243                         /* There is something to read from CGI */
1244                         char *rbuf = iobuf;
1245
1246                         /* Are we still buffering CGI output? */
1247                         if (out_cnt >= 0) {
1248                                 /* HTTP_200[] has single "\r\n" at the end.
1249                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1250                                  * CGI scripts MUST send their own header terminated by
1251                                  * empty line, then data. That's why we have only one
1252                                  * <cr><lf> pair here. We will output "200 OK" line
1253                                  * if needed, but CGI still has to provide blank line
1254                                  * between header and body */
1255
1256                                 /* Must use safe_read, not full_read, because
1257                                  * CGI may output a few first bytes and then wait
1258                                  * for POSTDATA without closing stdout.
1259                                  * With full_read we may wait here forever. */
1260                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1261                                 if (count <= 0) {
1262                                         /* eof (or error) and there was no "HTTP",
1263                                          * so write it, then write received data */
1264                                         if (out_cnt) {
1265                                                 full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
1266                                                 full_write(STDOUT_FILENO, rbuf, out_cnt);
1267                                         }
1268                                         break; /* CGI stdout is closed, exiting */
1269                                 }
1270                                 out_cnt += count;
1271                                 count = 0;
1272                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1273                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1274                                         /* send "HTTP/1.0 " */
1275                                         if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
1276                                                 break;
1277                                         rbuf += 8; /* skip "Status: " */
1278                                         count = out_cnt - 8;
1279                                         out_cnt = -1; /* buffering off */
1280                                 } else if (out_cnt >= 4) {
1281                                         /* Did CGI add "HTTP"? */
1282                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1283                                                 /* there is no "HTTP", do it ourself */
1284                                                 if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1285                                                         break;
1286                                         }
1287                                         /* Commented out:
1288                                         if (!strstr(rbuf, "ontent-")) {
1289                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1290                                         }
1291                                          * Counter-example of valid CGI without Content-type:
1292                                          * echo -en "HTTP/1.0 302 Found\r\n"
1293                                          * echo -en "Location: http://www.busybox.net\r\n"
1294                                          * echo -en "\r\n"
1295                                          */
1296                                         count = out_cnt;
1297                                         out_cnt = -1; /* buffering off */
1298                                 }
1299                         } else {
1300                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1301                                 if (count <= 0)
1302                                         break;  /* eof (or error) */
1303                         }
1304                         if (full_write(STDOUT_FILENO, rbuf, count) != count)
1305                                 break;
1306                         if (DEBUG)
1307                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1308                 } /* if (pfd[FROM_CGI].revents) */
1309         } /* while (1) */
1310         log_and_exit();
1311 }
1312 #endif
1313
1314 #if ENABLE_FEATURE_HTTPD_CGI
1315
1316 static void setenv1(const char *name, const char *value)
1317 {
1318         setenv(name, value ? value : "", 1);
1319 }
1320
1321 /*
1322  * Spawn CGI script, forward CGI's stdin/out <=> network
1323  *
1324  * Environment variables are set up and the script is invoked with pipes
1325  * for stdin/stdout.  If a POST is being done the script is fed the POST
1326  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1327  *
1328  * Parameters:
1329  * const char *url              The requested URL (with leading /).
1330  * int post_len                 Length of the POST body.
1331  * const char *cookie           For set HTTP_COOKIE.
1332  * const char *content_type     For set CONTENT_TYPE.
1333  */
1334 static void send_cgi_and_exit(
1335                 const char *url,
1336                 const char *request,
1337                 int post_len,
1338                 const char *cookie,
1339                 const char *content_type) NORETURN;
1340 static void send_cgi_and_exit(
1341                 const char *url,
1342                 const char *request,
1343                 int post_len,
1344                 const char *cookie,
1345                 const char *content_type)
1346 {
1347         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1348         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1349         char *script;
1350         int pid;
1351
1352         /* Make a copy. NB: caller guarantees:
1353          * url[0] == '/', url[1] != '/' */
1354         url = xstrdup(url);
1355
1356         /*
1357          * We are mucking with environment _first_ and then vfork/exec,
1358          * this allows us to use vfork safely. Parent doesn't care about
1359          * these environment changes anyway.
1360          */
1361
1362         /* Check for [dirs/]script.cgi/PATH_INFO */
1363         script = (char*)url;
1364         while ((script = strchr(script + 1, '/')) != NULL) {
1365                 *script = '\0';
1366                 if (!is_directory(url + 1, 1, NULL)) {
1367                         /* not directory, found script.cgi/PATH_INFO */
1368                         *script = '/';
1369                         break;
1370                 }
1371                 *script = '/'; /* is directory, find next '/' */
1372         }
1373         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1374         setenv1("REQUEST_METHOD", request);
1375         if (g_query) {
1376                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1377         } else {
1378                 setenv1("REQUEST_URI", url);
1379         }
1380         if (script != NULL)
1381                 *script = '\0';         /* cut off /PATH_INFO */
1382
1383         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1384         if (home_httpd[0] == '/') {
1385                 char *fullpath = concat_path_file(home_httpd, url);
1386                 setenv1("SCRIPT_FILENAME", fullpath);
1387         }
1388         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1389         setenv1("SCRIPT_NAME", url);
1390         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1391          * QUERY_STRING: The information which follows the ? in the URL
1392          * which referenced this script. This is the query information.
1393          * It should not be decoded in any fashion. This variable
1394          * should always be set when there is query information,
1395          * regardless of command line decoding. */
1396         /* (Older versions of bbox seem to do some decoding) */
1397         setenv1("QUERY_STRING", g_query);
1398         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1399         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1400         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1401         /* Having _separate_ variables for IP and port defeats
1402          * the purpose of having socket abstraction. Which "port"
1403          * are you using on Unix domain socket?
1404          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1405          * Oh well... */
1406         {
1407                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1408                 char *cp = strrchr(p, ':');
1409                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1410                         cp = NULL;
1411                 if (cp) *cp = '\0'; /* delete :PORT */
1412                 setenv1("REMOTE_ADDR", p);
1413                 if (cp) {
1414                         *cp = ':';
1415 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1416                         setenv1("REMOTE_PORT", cp + 1);
1417 #endif
1418                 }
1419         }
1420         setenv1("HTTP_USER_AGENT", user_agent);
1421         if (http_accept)
1422                 setenv1("HTTP_ACCEPT", http_accept);
1423         if (http_accept_language)
1424                 setenv1("HTTP_ACCEPT_LANGUAGE", http_accept_language);
1425         if (post_len)
1426                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1427         if (cookie)
1428                 setenv1("HTTP_COOKIE", cookie);
1429         if (content_type)
1430                 setenv1("CONTENT_TYPE", content_type);
1431 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1432         if (remoteuser) {
1433                 setenv1("REMOTE_USER", remoteuser);
1434                 putenv((char*)"AUTH_TYPE=Basic");
1435         }
1436 #endif
1437         if (referer)
1438                 setenv1("HTTP_REFERER", referer);
1439         setenv1("HTTP_HOST", host); /* set to "" if NULL */
1440         /* setenv1("SERVER_NAME", safe_gethostname()); - don't do this,
1441          * just run "env SERVER_NAME=xyz httpd ..." instead */
1442
1443         xpiped_pair(fromCgi);
1444         xpiped_pair(toCgi);
1445
1446         pid = vfork();
1447         if (pid < 0) {
1448                 /* TODO: log perror? */
1449                 log_and_exit();
1450         }
1451
1452         if (!pid) {
1453                 /* Child process */
1454                 char *argv[3];
1455
1456                 xfunc_error_retval = 242;
1457
1458                 /* NB: close _first_, then move fds! */
1459                 close(toCgi.wr);
1460                 close(fromCgi.rd);
1461                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1462                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1463                 /* User seeing stderr output can be a security problem.
1464                  * If CGI really wants that, it can always do dup itself. */
1465                 /* dup2(1, 2); */
1466
1467                 /* Chdiring to script's dir */
1468                 script = strrchr(url, '/');
1469                 if (script != url) { /* paranoia */
1470                         *script = '\0';
1471                         if (chdir(url + 1) != 0) {
1472                                 bb_perror_msg("chdir(%s)", url + 1);
1473                                 goto error_execing_cgi;
1474                         }
1475                         // not needed: *script = '/';
1476                 }
1477                 script++;
1478
1479                 /* set argv[0] to name without path */
1480                 argv[0] = script;
1481                 argv[1] = NULL;
1482
1483 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1484                 {
1485                         char *suffix = strrchr(script, '.');
1486
1487                         if (suffix) {
1488                                 Htaccess *cur;
1489                                 for (cur = script_i; cur; cur = cur->next) {
1490                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1491                                                 /* found interpreter name */
1492                                                 argv[0] = cur->after_colon;
1493                                                 argv[1] = script;
1494                                                 argv[2] = NULL;
1495                                                 break;
1496                                         }
1497                                 }
1498                         }
1499                 }
1500 #endif
1501                 /* restore default signal dispositions for CGI process */
1502                 bb_signals(0
1503                         | (1 << SIGCHLD)
1504                         | (1 << SIGPIPE)
1505                         | (1 << SIGHUP)
1506                         , SIG_DFL);
1507
1508                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1509                  * without any dir components and will only match a file
1510                  * in the current directory */
1511                 execv(argv[0], argv);
1512                 if (verbose)
1513                         bb_perror_msg("can't execute '%s'", argv[0]);
1514  error_execing_cgi:
1515                 /* send to stdout
1516                  * (we are CGI here, our stdout is pumped to the net) */
1517                 send_headers_and_exit(HTTP_NOT_FOUND);
1518         } /* end child */
1519
1520         /* Parent process */
1521
1522         /* Restore variables possibly changed by child */
1523         xfunc_error_retval = 0;
1524
1525         /* Pump data */
1526         close(fromCgi.wr);
1527         close(toCgi.rd);
1528         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1529 }
1530
1531 #endif          /* FEATURE_HTTPD_CGI */
1532
1533 /*
1534  * Send a file response to a HTTP request, and exit
1535  *
1536  * Parameters:
1537  * const char *url  The requested URL (with leading /).
1538  * what             What to send (headers/body/both).
1539  */
1540 static NOINLINE void send_file_and_exit(const char *url, int what)
1541 {
1542         char *suffix;
1543         int fd;
1544         ssize_t count;
1545
1546         if (content_gzip) {
1547                 /* does <url>.gz exist? Then use it instead */
1548                 char *gzurl = xasprintf("%s.gz", url);
1549                 fd = open(gzurl, O_RDONLY);
1550                 free(gzurl);
1551                 if (fd != -1) {
1552                         struct stat sb;
1553                         fstat(fd, &sb);
1554                         file_size = sb.st_size;
1555                         last_mod = sb.st_mtime;
1556                 } else {
1557                         IF_FEATURE_HTTPD_GZIP(content_gzip = 0;)
1558                         fd = open(url, O_RDONLY);
1559                 }
1560         } else {
1561                 fd = open(url, O_RDONLY);
1562         }
1563         if (fd < 0) {
1564                 if (DEBUG)
1565                         bb_perror_msg("can't open '%s'", url);
1566                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1567                  * IOW: it is unsafe to call send_headers_and_exit
1568                  * if what is SEND_BODY! Can recurse! */
1569                 if (what != SEND_BODY)
1570                         send_headers_and_exit(HTTP_NOT_FOUND);
1571                 log_and_exit();
1572         }
1573         /* If you want to know about EPIPE below
1574          * (happens if you abort downloads from local httpd): */
1575         signal(SIGPIPE, SIG_IGN);
1576
1577         /* If not found, default is "application/octet-stream" */
1578         found_mime_type = "application/octet-stream";
1579         suffix = strrchr(url, '.');
1580         if (suffix) {
1581                 static const char suffixTable[] ALIGN1 =
1582                         /* Shorter suffix must be first:
1583                          * ".html.htm" will fail for ".htm"
1584                          */
1585                         ".txt.h.c.cc.cpp\0" "text/plain\0"
1586                         /* .htm line must be after .h line */
1587                         ".htm.html\0" "text/html\0"
1588                         ".jpg.jpeg\0" "image/jpeg\0"
1589                         ".gif\0"      "image/gif\0"
1590                         ".png\0"      "image/png\0"
1591                         /* .css line must be after .c line */
1592                         ".css\0"      "text/css\0"
1593                         ".wav\0"      "audio/wav\0"
1594                         ".avi\0"      "video/x-msvideo\0"
1595                         ".qt.mov\0"   "video/quicktime\0"
1596                         ".mpe.mpeg\0" "video/mpeg\0"
1597                         ".mid.midi\0" "audio/midi\0"
1598                         ".mp3\0"      "audio/mpeg\0"
1599 #if 0  /* unpopular */
1600                         ".au\0"       "audio/basic\0"
1601                         ".pac\0"      "application/x-ns-proxy-autoconfig\0"
1602                         ".vrml.wrl\0" "model/vrml\0"
1603 #endif
1604                         /* compiler adds another "\0" here */
1605                 ;
1606                 Htaccess *cur;
1607
1608                 /* Examine built-in table */
1609                 const char *table = suffixTable;
1610                 const char *table_next;
1611                 for (; *table; table = table_next) {
1612                         const char *try_suffix;
1613                         const char *mime_type;
1614                         mime_type  = table + strlen(table) + 1;
1615                         table_next = mime_type + strlen(mime_type) + 1;
1616                         try_suffix = strstr(table, suffix);
1617                         if (!try_suffix)
1618                                 continue;
1619                         try_suffix += strlen(suffix);
1620                         if (*try_suffix == '\0' || *try_suffix == '.') {
1621                                 found_mime_type = mime_type;
1622                                 break;
1623                         }
1624                         /* Example: strstr(table, ".av") != NULL, but it
1625                          * does not match ".avi" after all and we end up here.
1626                          * The table is arranged so that in this case we know
1627                          * that it can't match anything in the following lines,
1628                          * and we stop the search: */
1629                         break;
1630                 }
1631                 /* ...then user's table */
1632                 for (cur = mime_a; cur; cur = cur->next) {
1633                         if (strcmp(cur->before_colon, suffix) == 0) {
1634                                 found_mime_type = cur->after_colon;
1635                                 break;
1636                         }
1637                 }
1638         }
1639
1640         if (DEBUG)
1641                 bb_error_msg("sending file '%s' content-type: %s",
1642                         url, found_mime_type);
1643
1644 #if ENABLE_FEATURE_HTTPD_RANGES
1645         if (what == SEND_BODY /* err pages and ranges don't mix */
1646          || content_gzip /* we are sending compressed page: can't do ranges */  ///why?
1647         ) {
1648                 range_start = 0;
1649         }
1650         range_len = MAXINT(off_t);
1651         if (range_start) {
1652                 if (!range_end) {
1653                         range_end = file_size - 1;
1654                 }
1655                 if (range_end < range_start
1656                  || lseek(fd, range_start, SEEK_SET) != range_start
1657                 ) {
1658                         lseek(fd, 0, SEEK_SET);
1659                         range_start = 0;
1660                 } else {
1661                         range_len = range_end - range_start + 1;
1662                         send_headers(HTTP_PARTIAL_CONTENT);
1663                         what = SEND_BODY;
1664                 }
1665         }
1666 #endif
1667         if (what & SEND_HEADERS)
1668                 send_headers(HTTP_OK);
1669 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1670         {
1671                 off_t offset = range_start;
1672                 while (1) {
1673                         /* sz is rounded down to 64k */
1674                         ssize_t sz = MAXINT(ssize_t) - 0xffff;
1675                         IF_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1676                         count = sendfile(STDOUT_FILENO, fd, &offset, sz);
1677                         if (count < 0) {
1678                                 if (offset == range_start)
1679                                         break; /* fall back to read/write loop */
1680                                 goto fin;
1681                         }
1682                         IF_FEATURE_HTTPD_RANGES(range_len -= sz;)
1683                         if (count == 0 || range_len == 0)
1684                                 log_and_exit();
1685                 }
1686         }
1687 #endif
1688         while ((count = safe_read(fd, iobuf, IOBUF_SIZE)) > 0) {
1689                 ssize_t n;
1690                 IF_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1691                 n = full_write(STDOUT_FILENO, iobuf, count);
1692                 if (count != n)
1693                         break;
1694                 IF_FEATURE_HTTPD_RANGES(range_len -= count;)
1695                 if (range_len == 0)
1696                         break;
1697         }
1698         if (count < 0) {
1699  IF_FEATURE_HTTPD_USE_SENDFILE(fin:)
1700                 if (verbose > 1)
1701                         bb_perror_msg("error");
1702         }
1703         log_and_exit();
1704 }
1705
1706 static int checkPermIP(void)
1707 {
1708         Htaccess_IP *cur;
1709
1710         for (cur = ip_a_d; cur; cur = cur->next) {
1711 #if DEBUG
1712                 fprintf(stderr,
1713                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1714                         rmt_ip_str,
1715                         (unsigned char)(cur->ip >> 24),
1716                         (unsigned char)(cur->ip >> 16),
1717                         (unsigned char)(cur->ip >> 8),
1718                         (unsigned char)(cur->ip),
1719                         (unsigned char)(cur->mask >> 24),
1720                         (unsigned char)(cur->mask >> 16),
1721                         (unsigned char)(cur->mask >> 8),
1722                         (unsigned char)(cur->mask)
1723                 );
1724 #endif
1725                 if ((rmt_ip & cur->mask) == cur->ip)
1726                         return (cur->allow_deny == 'A'); /* A -> 1 */
1727         }
1728
1729         return !flg_deny_all; /* depends on whether we saw "D:*" */
1730 }
1731
1732 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1733 /*
1734  * Config file entries are of the form "/<path>:<user>:<passwd>".
1735  * If config file has no prefix match for path, access is allowed.
1736  *
1737  * path                 The file path
1738  * user_and_passwd      "user:passwd" to validate
1739  *
1740  * Returns 1 if user_and_passwd is OK.
1741  */
1742 static int check_user_passwd(const char *path, const char *user_and_passwd)
1743 {
1744         Htaccess *cur;
1745         const char *prev = NULL;
1746
1747         for (cur = g_auth; cur; cur = cur->next) {
1748                 const char *dir_prefix;
1749                 size_t len;
1750
1751                 dir_prefix = cur->before_colon;
1752
1753                 /* WHY? */
1754                 /* If already saw a match, don't accept other different matches */
1755                 if (prev && strcmp(prev, dir_prefix) != 0)
1756                         continue;
1757
1758                 if (DEBUG)
1759                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
1760
1761                 /* If it's not a prefix match, continue searching */
1762                 len = strlen(dir_prefix);
1763                 if (len != 1 /* dir_prefix "/" matches all, don't need to check */
1764                  && (strncmp(dir_prefix, path, len) != 0
1765                     || (path[len] != '/' && path[len] != '\0'))
1766                 ) {
1767                         continue;
1768                 }
1769
1770                 /* Path match found */
1771                 prev = dir_prefix;
1772
1773                 if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1774                         char *md5_passwd;
1775
1776                         md5_passwd = strchr(cur->after_colon, ':');
1777                         if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
1778                          && md5_passwd[3] == '$' && md5_passwd[4]
1779                         ) {
1780                                 char *encrypted;
1781                                 int r, user_len_p1;
1782
1783                                 md5_passwd++;
1784                                 user_len_p1 = md5_passwd - cur->after_colon;
1785                                 /* comparing "user:" */
1786                                 if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
1787                                         continue;
1788                                 }
1789
1790                                 encrypted = pw_encrypt(
1791                                         user_and_passwd + user_len_p1 /* cleartext pwd from user */,
1792                                         md5_passwd /*salt */, 1 /* cleanup */);
1793                                 r = strcmp(encrypted, md5_passwd);
1794                                 free(encrypted);
1795                                 if (r == 0)
1796                                         goto set_remoteuser_var; /* Ok */
1797                                 continue;
1798                         }
1799                 }
1800
1801                 /* Comparing plaintext "user:pass" in one go */
1802                 if (strcmp(cur->after_colon, user_and_passwd) == 0) {
1803  set_remoteuser_var:
1804                         remoteuser = xstrndup(user_and_passwd,
1805                                         strchrnul(user_and_passwd, ':') - user_and_passwd);
1806                         return 1; /* Ok */
1807                 }
1808         } /* for */
1809
1810         /* 0(bad) if prev is set: matches were found but passwd was wrong */
1811         return (prev == NULL);
1812 }
1813 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1814
1815 #if ENABLE_FEATURE_HTTPD_PROXY
1816 static Htaccess_Proxy *find_proxy_entry(const char *url)
1817 {
1818         Htaccess_Proxy *p;
1819         for (p = proxy; p; p = p->next) {
1820                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1821                         return p;
1822         }
1823         return NULL;
1824 }
1825 #endif
1826
1827 /*
1828  * Handle timeouts
1829  */
1830 static void send_REQUEST_TIMEOUT_and_exit(int sig) NORETURN;
1831 static void send_REQUEST_TIMEOUT_and_exit(int sig UNUSED_PARAM)
1832 {
1833         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1834 }
1835
1836 /*
1837  * Handle an incoming http request and exit.
1838  */
1839 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
1840 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1841 {
1842         static const char request_GET[] ALIGN1 = "GET";
1843         struct stat sb;
1844         char *urlcopy;
1845         char *urlp;
1846         char *tptr;
1847 #if ENABLE_FEATURE_HTTPD_CGI
1848         static const char request_HEAD[] ALIGN1 = "HEAD";
1849         const char *prequest;
1850         char *cookie = NULL;
1851         char *content_type = NULL;
1852         unsigned long length = 0;
1853 #elif ENABLE_FEATURE_HTTPD_PROXY
1854 #define prequest request_GET
1855         unsigned long length = 0;
1856 #endif
1857 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1858         smallint authorized = -1;
1859 #endif
1860         smallint ip_allowed;
1861         char http_major_version;
1862 #if ENABLE_FEATURE_HTTPD_PROXY
1863         char http_minor_version;
1864         char *header_buf = header_buf; /* for gcc */
1865         char *header_ptr = header_ptr;
1866         Htaccess_Proxy *proxy_entry;
1867 #endif
1868
1869         /* Allocation of iobuf is postponed until now
1870          * (IOW, server process doesn't need to waste 8k) */
1871         iobuf = xmalloc(IOBUF_SIZE);
1872
1873         rmt_ip = 0;
1874         if (fromAddr->u.sa.sa_family == AF_INET) {
1875                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1876         }
1877 #if ENABLE_FEATURE_IPV6
1878         if (fromAddr->u.sa.sa_family == AF_INET6
1879          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1880          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1881          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1882                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1883 #endif
1884         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1885                 /* NB: can be NULL (user runs httpd -i by hand?) */
1886                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1887         }
1888         if (verbose) {
1889                 /* this trick makes -v logging much simpler */
1890                 if (rmt_ip_str)
1891                         applet_name = rmt_ip_str;
1892                 if (verbose > 2)
1893                         bb_error_msg("connected");
1894         }
1895
1896         /* Install timeout handler. get_line() needs it. */
1897         signal(SIGALRM, send_REQUEST_TIMEOUT_and_exit);
1898
1899         if (!get_line()) /* EOF or error or empty line */
1900                 send_headers_and_exit(HTTP_BAD_REQUEST);
1901
1902         /* Determine type of request (GET/POST) */
1903         urlp = strpbrk(iobuf, " \t");
1904         if (urlp == NULL)
1905                 send_headers_and_exit(HTTP_BAD_REQUEST);
1906         *urlp++ = '\0';
1907 #if ENABLE_FEATURE_HTTPD_CGI
1908         prequest = request_GET;
1909         if (strcasecmp(iobuf, prequest) != 0) {
1910                 prequest = request_HEAD;
1911                 if (strcasecmp(iobuf, prequest) != 0) {
1912                         prequest = "POST";
1913                         if (strcasecmp(iobuf, prequest) != 0)
1914                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1915                 }
1916         }
1917 #else
1918         if (strcasecmp(iobuf, request_GET) != 0)
1919                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1920 #endif
1921         urlp = skip_whitespace(urlp);
1922         if (urlp[0] != '/')
1923                 send_headers_and_exit(HTTP_BAD_REQUEST);
1924
1925         /* Find end of URL and parse HTTP version, if any */
1926         http_major_version = '0';
1927         IF_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1928         tptr = strchrnul(urlp, ' ');
1929         /* Is it " HTTP/"? */
1930         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1931                 http_major_version = tptr[6];
1932                 IF_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1933         }
1934         *tptr = '\0';
1935
1936         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1937         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1938         /*if (urlcopy == NULL)
1939          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1940         strcpy(urlcopy, urlp);
1941         /* NB: urlcopy ptr is never changed after this */
1942
1943         /* Extract url args if present */
1944         g_query = NULL;
1945         tptr = strchr(urlcopy, '?');
1946         if (tptr) {
1947                 *tptr++ = '\0';
1948                 g_query = tptr;
1949         }
1950
1951         /* Decode URL escape sequences */
1952         tptr = decodeString(urlcopy, 0);
1953         if (tptr == NULL)
1954                 send_headers_and_exit(HTTP_BAD_REQUEST);
1955         if (tptr == urlcopy + 1) {
1956                 /* '/' or NUL is encoded */
1957                 send_headers_and_exit(HTTP_NOT_FOUND);
1958         }
1959
1960         /* Canonicalize path */
1961         /* Algorithm stolen from libbb bb_simplify_path(),
1962          * but don't strdup, retain trailing slash, protect root */
1963         urlp = tptr = urlcopy;
1964         do {
1965                 if (*urlp == '/') {
1966                         /* skip duplicate (or initial) slash */
1967                         if (*tptr == '/') {
1968                                 continue;
1969                         }
1970                         if (*tptr == '.') {
1971                                 /* skip extra "/./" */
1972                                 if (tptr[1] == '/' || !tptr[1]) {
1973                                         continue;
1974                                 }
1975                                 /* "..": be careful */
1976                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1977                                         ++tptr;
1978                                         if (urlp == urlcopy) /* protect root */
1979                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1980                                         while (*--urlp != '/') /* omit previous dir */;
1981                                                 continue;
1982                                 }
1983                         }
1984                 }
1985                 *++urlp = *tptr;
1986         } while (*++tptr);
1987         *++urlp = '\0';       /* terminate after last character */
1988
1989         /* If URL is a directory, add '/' */
1990         if (urlp[-1] != '/') {
1991                 if (is_directory(urlcopy + 1, 1, NULL)) {
1992                         found_moved_temporarily = urlcopy;
1993                 }
1994         }
1995
1996         /* Log it */
1997         if (verbose > 1)
1998                 bb_error_msg("url:%s", urlcopy);
1999
2000         tptr = urlcopy;
2001         ip_allowed = checkPermIP();
2002         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
2003                 /* have path1/path2 */
2004                 *tptr = '\0';
2005                 if (is_directory(urlcopy + 1, 1, NULL)) {
2006                         /* may have subdir config */
2007                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
2008                         ip_allowed = checkPermIP();
2009                 }
2010                 *tptr = '/';
2011         }
2012
2013 #if ENABLE_FEATURE_HTTPD_PROXY
2014         proxy_entry = find_proxy_entry(urlcopy);
2015         if (proxy_entry)
2016                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
2017 #endif
2018
2019         if (http_major_version >= '0') {
2020                 /* Request was with "... HTTP/nXXX", and n >= 0 */
2021
2022                 /* Read until blank line */
2023                 while (1) {
2024                         if (!get_line())
2025                                 break; /* EOF or error or empty line */
2026                         if (DEBUG)
2027                                 bb_error_msg("header: '%s'", iobuf);
2028
2029 #if ENABLE_FEATURE_HTTPD_PROXY
2030                         /* We need 2 more bytes for yet another "\r\n" -
2031                          * see near fdprintf(proxy_fd...) further below */
2032                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
2033                                 int len = strlen(iobuf);
2034                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
2035                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
2036                                 memcpy(header_ptr, iobuf, len);
2037                                 header_ptr += len;
2038                                 header_ptr[0] = '\r';
2039                                 header_ptr[1] = '\n';
2040                                 header_ptr += 2;
2041                         }
2042 #endif
2043
2044 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
2045                         /* Try and do our best to parse more lines */
2046                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
2047                                 /* extra read only for POST */
2048                                 if (prequest != request_GET
2049 # if ENABLE_FEATURE_HTTPD_CGI
2050                                  && prequest != request_HEAD
2051 # endif
2052                                 ) {
2053                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
2054                                         if (!tptr[0])
2055                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
2056                                         /* not using strtoul: it ignores leading minus! */
2057                                         length = bb_strtou(tptr, NULL, 10);
2058                                         /* length is "ulong", but we need to pass it to int later */
2059                                         if (errno || length > INT_MAX)
2060                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
2061                                 }
2062                         }
2063 #endif
2064 #if ENABLE_FEATURE_HTTPD_CGI
2065                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
2066                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
2067                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
2068                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
2069                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
2070                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
2071                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2072                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2073                         } else if (STRNCASECMP(iobuf, "Host:") == 0) {
2074                                 host = xstrdup(skip_whitespace(iobuf + sizeof("Host:")-1));
2075                         } else if (STRNCASECMP(iobuf, "Accept:") == 0) {
2076                                 http_accept = xstrdup(skip_whitespace(iobuf + sizeof("Accept:")-1));
2077                         } else if (STRNCASECMP(iobuf, "Accept-Language:") == 0) {
2078                                 http_accept_language = xstrdup(skip_whitespace(iobuf + sizeof("Accept-Language:")-1));
2079                         }
2080 #endif
2081 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2082                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2083                                 /* We only allow Basic credentials.
2084                                  * It shows up as "Authorization: Basic <user>:<passwd>" where
2085                                  * "<user>:<passwd>" is base64 encoded.
2086                                  */
2087                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2088                                 if (STRNCASECMP(tptr, "Basic") != 0)
2089                                         continue;
2090                                 tptr += sizeof("Basic")-1;
2091                                 /* decodeBase64() skips whitespace itself */
2092                                 decodeBase64(tptr);
2093                                 authorized = check_user_passwd(urlcopy, tptr);
2094                         }
2095 #endif
2096 #if ENABLE_FEATURE_HTTPD_RANGES
2097                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2098                                 /* We know only bytes=NNN-[MMM] */
2099                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2100                                 if (strncmp(s, "bytes=", 6) == 0) {
2101                                         s += sizeof("bytes=")-1;
2102                                         range_start = BB_STRTOOFF(s, &s, 10);
2103                                         if (s[0] != '-' || range_start < 0) {
2104                                                 range_start = 0;
2105                                         } else if (s[1]) {
2106                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2107                                                 if (errno || range_end < range_start)
2108                                                         range_start = 0;
2109                                         }
2110                                 }
2111                         }
2112 #endif
2113 #if ENABLE_FEATURE_HTTPD_GZIP
2114                         if (STRNCASECMP(iobuf, "Accept-Encoding:") == 0) {
2115                                 /* Note: we do not support "gzip;q=0"
2116                                  * method of _disabling_ gzip
2117                                  * delivery. No one uses that, though */
2118                                 const char *s = strstr(iobuf, "gzip");
2119                                 if (s) {
2120                                         // want more thorough checks?
2121                                         //if (s[-1] == ' '
2122                                         // || s[-1] == ','
2123                                         // || s[-1] == ':'
2124                                         //) {
2125                                                 content_gzip = 1;
2126                                         //}
2127                                 }
2128                         }
2129 #endif
2130                 } /* while extra header reading */
2131         }
2132
2133         /* We are done reading headers, disable peer timeout */
2134         alarm(0);
2135
2136         if (strcmp(bb_basename(urlcopy), HTTPD_CONF) == 0 || !ip_allowed) {
2137                 /* protect listing [/path]/httpd.conf or IP deny */
2138                 send_headers_and_exit(HTTP_FORBIDDEN);
2139         }
2140
2141 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2142         /* Case: no "Authorization:" was seen, but page does require passwd.
2143          * Check that with dummy user:pass */
2144         if (authorized < 0)
2145                 authorized = check_user_passwd(urlcopy, ":");
2146         if (!authorized)
2147                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2148 #endif
2149
2150         if (found_moved_temporarily) {
2151                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2152         }
2153
2154 #if ENABLE_FEATURE_HTTPD_PROXY
2155         if (proxy_entry != NULL) {
2156                 int proxy_fd;
2157                 len_and_sockaddr *lsa;
2158
2159                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2160                 if (proxy_fd < 0)
2161                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2162                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2163                 if (lsa == NULL)
2164                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2165                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2166                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2167                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2168                                 prequest, /* GET or POST */
2169                                 proxy_entry->url_to, /* url part 1 */
2170                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2171                                 (g_query ? "?" : ""), /* "?" (maybe) */
2172                                 (g_query ? g_query : ""), /* query string (maybe) */
2173                                 http_major_version, http_minor_version);
2174                 header_ptr[0] = '\r';
2175                 header_ptr[1] = '\n';
2176                 header_ptr += 2;
2177                 write(proxy_fd, header_buf, header_ptr - header_buf);
2178                 free(header_buf); /* on the order of 8k, free it */
2179                 cgi_io_loop_and_exit(proxy_fd, proxy_fd, length);
2180         }
2181 #endif
2182
2183         tptr = urlcopy + 1;      /* skip first '/' */
2184
2185 #if ENABLE_FEATURE_HTTPD_CGI
2186         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2187                 if (tptr[8] == '\0') {
2188                         /* protect listing "cgi-bin/" */
2189                         send_headers_and_exit(HTTP_FORBIDDEN);
2190                 }
2191                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2192         }
2193 #endif
2194
2195         if (urlp[-1] == '/')
2196                 strcpy(urlp, index_page);
2197         if (stat(tptr, &sb) == 0) {
2198 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2199                 char *suffix = strrchr(tptr, '.');
2200                 if (suffix) {
2201                         Htaccess *cur;
2202                         for (cur = script_i; cur; cur = cur->next) {
2203                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2204                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2205                                 }
2206                         }
2207                 }
2208 #endif
2209                 file_size = sb.st_size;
2210                 last_mod = sb.st_mtime;
2211         }
2212 #if ENABLE_FEATURE_HTTPD_CGI
2213         else if (urlp[-1] == '/') {
2214                 /* It's a dir URL and there is no index.html
2215                  * Try cgi-bin/index.cgi */
2216                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2217                         urlp[0] = '\0';
2218                         g_query = urlcopy;
2219                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2220                 }
2221         }
2222         /* else fall through to send_file, it errors out if open fails: */
2223
2224         if (prequest != request_GET && prequest != request_HEAD) {
2225                 /* POST for files does not make sense */
2226                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2227         }
2228         send_file_and_exit(tptr,
2229                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2230         );
2231 #else
2232         send_file_and_exit(tptr, SEND_HEADERS_AND_BODY);
2233 #endif
2234 }
2235
2236 /*
2237  * The main http server function.
2238  * Given a socket, listen for new connections and farm out
2239  * the processing as a [v]forked process.
2240  * Never returns.
2241  */
2242 #if BB_MMU
2243 static void mini_httpd(int server_socket) NORETURN;
2244 static void mini_httpd(int server_socket)
2245 {
2246         /* NB: it's best to not use xfuncs in this loop before fork().
2247          * Otherwise server may die on transient errors (temporary
2248          * out-of-memory condition, etc), which is Bad(tm).
2249          * Try to do any dangerous calls after fork.
2250          */
2251         while (1) {
2252                 int n;
2253                 len_and_sockaddr fromAddr;
2254
2255                 /* Wait for connections... */
2256                 fromAddr.len = LSA_SIZEOF_SA;
2257                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2258                 if (n < 0)
2259                         continue;
2260
2261                 /* set the KEEPALIVE option to cull dead connections */
2262                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2263
2264                 if (fork() == 0) {
2265                         /* child */
2266                         /* Do not reload config on HUP */
2267                         signal(SIGHUP, SIG_IGN);
2268                         close(server_socket);
2269                         xmove_fd(n, 0);
2270                         xdup2(0, 1);
2271
2272                         handle_incoming_and_exit(&fromAddr);
2273                 }
2274                 /* parent, or fork failed */
2275                 close(n);
2276         } /* while (1) */
2277         /* never reached */
2278 }
2279 #else
2280 static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
2281 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2282 {
2283         char *argv_copy[argc + 2];
2284
2285         argv_copy[0] = argv[0];
2286         argv_copy[1] = (char*)"-i";
2287         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2288
2289         /* NB: it's best to not use xfuncs in this loop before vfork().
2290          * Otherwise server may die on transient errors (temporary
2291          * out-of-memory condition, etc), which is Bad(tm).
2292          * Try to do any dangerous calls after fork.
2293          */
2294         while (1) {
2295                 int n;
2296                 len_and_sockaddr fromAddr;
2297
2298                 /* Wait for connections... */
2299                 fromAddr.len = LSA_SIZEOF_SA;
2300                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2301                 if (n < 0)
2302                         continue;
2303
2304                 /* set the KEEPALIVE option to cull dead connections */
2305                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2306
2307                 if (vfork() == 0) {
2308                         /* child */
2309                         /* Do not reload config on HUP */
2310                         signal(SIGHUP, SIG_IGN);
2311                         close(server_socket);
2312                         xmove_fd(n, 0);
2313                         xdup2(0, 1);
2314
2315                         /* Run a copy of ourself in inetd mode */
2316                         re_exec(argv_copy);
2317                 }
2318                 /* parent, or vfork failed */
2319                 close(n);
2320         } /* while (1) */
2321         /* never reached */
2322 }
2323 #endif
2324
2325 /*
2326  * Process a HTTP connection on stdin/out.
2327  * Never returns.
2328  */
2329 static void mini_httpd_inetd(void) NORETURN;
2330 static void mini_httpd_inetd(void)
2331 {
2332         len_and_sockaddr fromAddr;
2333
2334         memset(&fromAddr, 0, sizeof(fromAddr));
2335         fromAddr.len = LSA_SIZEOF_SA;
2336         /* NB: can fail if user runs it by hand and types in http cmds */
2337         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2338         handle_incoming_and_exit(&fromAddr);
2339 }
2340
2341 static void sighup_handler(int sig UNUSED_PARAM)
2342 {
2343         parse_conf(DEFAULT_PATH_HTTPD_CONF, SIGNALED_PARSE);
2344 }
2345
2346 enum {
2347         c_opt_config_file = 0,
2348         d_opt_decode_url,
2349         h_opt_home_httpd,
2350         IF_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2351         IF_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2352         IF_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2353         IF_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2354         p_opt_port      ,
2355         p_opt_inetd     ,
2356         p_opt_foreground,
2357         p_opt_verbose   ,
2358         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2359         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2360         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2361         OPT_ENCODE_URL  = IF_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2362         OPT_REALM       = IF_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2363         OPT_MD5         = IF_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2364         OPT_SETUID      = IF_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2365         OPT_PORT        = 1 << p_opt_port,
2366         OPT_INETD       = 1 << p_opt_inetd,
2367         OPT_FOREGROUND  = 1 << p_opt_foreground,
2368         OPT_VERBOSE     = 1 << p_opt_verbose,
2369 };
2370
2371
2372 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2373 int httpd_main(int argc UNUSED_PARAM, char **argv)
2374 {
2375         int server_socket = server_socket; /* for gcc */
2376         unsigned opt;
2377         char *url_for_decode;
2378         IF_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2379         IF_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2380         IF_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2381         IF_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2382
2383         INIT_G();
2384
2385 #if ENABLE_LOCALE_SUPPORT
2386         /* Undo busybox.c: we want to speak English in http (dates etc) */
2387         setlocale(LC_TIME, "C");
2388 #endif
2389
2390         home_httpd = xrealloc_getcwd_or_warn(NULL);
2391         /* -v counts, -i implies -f */
2392         opt_complementary = "vv:if";
2393         /* We do not "absolutize" path given by -h (home) opt.
2394          * If user gives relative path in -h,
2395          * $SCRIPT_FILENAME will not be set. */
2396         opt = getopt32(argv, "c:d:h:"
2397                         IF_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2398                         IF_FEATURE_HTTPD_BASIC_AUTH("r:")
2399                         IF_FEATURE_HTTPD_AUTH_MD5("m:")
2400                         IF_FEATURE_HTTPD_SETUID("u:")
2401                         "p:ifv",
2402                         &opt_c_configFile, &url_for_decode, &home_httpd
2403                         IF_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2404                         IF_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2405                         IF_FEATURE_HTTPD_AUTH_MD5(, &pass)
2406                         IF_FEATURE_HTTPD_SETUID(, &s_ugid)
2407                         , &bind_addr_or_port
2408                         , &verbose
2409                 );
2410         if (opt & OPT_DECODE_URL) {
2411                 fputs(decodeString(url_for_decode, 1), stdout);
2412                 return 0;
2413         }
2414 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2415         if (opt & OPT_ENCODE_URL) {
2416                 fputs(encodeString(url_for_encode), stdout);
2417                 return 0;
2418         }
2419 #endif
2420 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2421         if (opt & OPT_MD5) {
2422                 char salt[sizeof("$1$XXXXXXXX")];
2423                 salt[0] = '$';
2424                 salt[1] = '1';
2425                 salt[2] = '$';
2426                 crypt_make_salt(salt + 3, 4);
2427                 puts(pw_encrypt(pass, salt, 1));
2428                 return 0;
2429         }
2430 #endif
2431 #if ENABLE_FEATURE_HTTPD_SETUID
2432         if (opt & OPT_SETUID) {
2433                 xget_uidgid(&ugid, s_ugid);
2434         }
2435 #endif
2436
2437 #if !BB_MMU
2438         if (!(opt & OPT_FOREGROUND)) {
2439                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2440         }
2441 #endif
2442
2443         xchdir(home_httpd);
2444         if (!(opt & OPT_INETD)) {
2445                 signal(SIGCHLD, SIG_IGN);
2446                 server_socket = openServer();
2447 #if ENABLE_FEATURE_HTTPD_SETUID
2448                 /* drop privileges */
2449                 if (opt & OPT_SETUID) {
2450                         if (ugid.gid != (gid_t)-1) {
2451                                 if (setgroups(1, &ugid.gid) == -1)
2452                                         bb_perror_msg_and_die("setgroups");
2453                                 xsetgid(ugid.gid);
2454                         }
2455                         xsetuid(ugid.uid);
2456                 }
2457 #endif
2458         }
2459
2460 #if 0
2461         /* User can do it himself: 'env - PATH="$PATH" httpd'
2462          * We don't do it because we don't want to screw users
2463          * which want to do
2464          * 'env - VAR1=val1 VAR2=val2 httpd'
2465          * and have VAR1 and VAR2 values visible in their CGIs.
2466          * Besides, it is also smaller. */
2467         {
2468                 char *p = getenv("PATH");
2469                 /* env strings themself are not freed, no need to xstrdup(p): */
2470                 clearenv();
2471                 if (p)
2472                         putenv(p - 5);
2473 //              if (!(opt & OPT_INETD))
2474 //                      setenv_long("SERVER_PORT", ???);
2475         }
2476 #endif
2477
2478         parse_conf(DEFAULT_PATH_HTTPD_CONF, FIRST_PARSE);
2479         if (!(opt & OPT_INETD))
2480                 signal(SIGHUP, sighup_handler);
2481
2482         xfunc_error_retval = 0;
2483         if (opt & OPT_INETD)
2484                 mini_httpd_inetd();
2485 #if BB_MMU
2486         if (!(opt & OPT_FOREGROUND))
2487                 bb_daemonize(0); /* don't change current directory */
2488         mini_httpd(server_socket); /* never returns */
2489 #else
2490         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2491 #endif
2492         /* return 0; */
2493 }