networking/httpd.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * httpd implementation for busybox
   4  *
   5  * Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
   6  * Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * simplify patch stolen from libbb without using strdup
   9  *
  10  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  11  *
  12  *****************************************************************************
  13  *
  14  * Typical usage:
  15  *   for non root user
  16  * httpd -p 8080 -h $HOME/public_html
  17  *   or for daemon start from rc script with uid=0:
  18  * httpd -u www
  19  * This is equivalent if www user have uid=80 to
  20  * httpd -p 80 -u 80 -h /www -c /etc/httpd.conf -r "Web Server Authentication"
  21  *
  22  *
  23  * When a url starts by "/cgi-bin/" it is assumed to be a cgi script.  The
  24  * server changes directory to the location of the script and executes it
  25  * after setting QUERY_STRING and other environment variables.
  26  *
  27  * Doc:
  28  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
  29  *
  30  * The server can also be invoked as a url arg decoder and html text encoder
  31  * as follows:
  32  *  foo=`httpd -d $foo`           # decode "Hello%20World" as "Hello World"
  33  *  bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
  34  * Note that url encoding for arguments is not the same as html encoding for
  35  * presentation.  -d decodes a url-encoded argument while -e encodes in html
  36  * for page display.
  37  *
  38  * httpd.conf has the following format:
  39  *
  40  * A:172.20.         # Allow address from 172.20.0.0/16
  41  * A:10.0.0.0/25     # Allow any address from 10.0.0.0-10.0.0.127
  42  * A:10.0.0.0/255.255.255.128  # Allow any address that previous set
  43  * A:127.0.0.1       # Allow local loopback connections
  44  * D:*               # Deny from other IP connections
  45  * E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
  46  * I:index.html      # Show index.html when a directory is requested
  47  *
  48  * P:/url:[http://]hostname[:port]/new/path
  49  *                   # When /urlXXXXXX is requested, reverse proxy
  50  *                   # it to http://hostname[:port]/new/pathXXXXXX
  51  *
  52  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
  53  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
  54  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
  55  * .au:audio/basic   # additional mime type for audio.au files
  56  * *.php:/path/php   # running cgi.php scripts through an interpreter
  57  *
  58  * A/D may be as a/d or allow/deny - first char case insensitive
  59  * Deny IP rules take precedence over allow rules.
  60  *
  61  *
  62  * The Deny/Allow IP logic:
  63  *
  64  *  - Default is to allow all.  No addresses are denied unless
  65  *         denied with a D: rule.
  66  *  - Order of Deny/Allow rules is significant
  67  *  - Deny rules take precedence over allow rules.
  68  *  - If a deny all rule (D:*) is used it acts as a catch-all for unmatched
  69  *       addresses.
  70  *  - Specification of Allow all (A:*) is a no-op
  71  *
  72  * Example:
  73  *   1. Allow only specified addresses
  74  *     A:172.20          # Allow any address that begins with 172.20.
  75  *     A:10.10.          # Allow any address that begins with 10.10.
  76  *     A:127.0.0.1       # Allow local loopback connections
  77  *     D:*               # Deny from other IP connections
  78  *
  79  *   2. Only deny specified addresses
  80  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
  81  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
  82  *     A:*             # (optional line added for clarity)
  83  *
  84  * If a sub directory contains a config file it is parsed and merged with
  85  * any existing settings as if it was appended to the original configuration.
  86  *
  87  * subdir paths are relative to the containing subdir and thus cannot
  88  * affect the parent rules.
  89  *
  90  * Note that since the sub dir is parsed in the forked thread servicing the
  91  * subdir http request, any merge is discarded when the process exits.  As a
  92  * result, the subdir settings only have a lifetime of a single request.
  93  *
  94  * Custom error pages can contain an absolute path or be relative to
  95  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
  96  * page can only be defined in the root configuration file and are not taken
  97  * into account in local (directories) config files.
  98  *
  99  * If -c is not set, an attempt will be made to open the default
 100  * root configuration file.  If -c is set and the file is not found, the
 101  * server exits with an error.
 102  *
 103  */
 104
 105 #include "libbb.h"
 106 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
 107 #include <sys/sendfile.h>
 108 #endif
 109
 110 //#define DEBUG 1
 111 #define DEBUG 0
 112
 113 #define IOBUF_SIZE 8192    /* IO buffer */
 114
 115 /* amount of buffering in a pipe */
 116 #ifndef PIPE_BUF
 117 # define PIPE_BUF 4096
 118 #endif
 119 #if PIPE_BUF >= IOBUF_SIZE
 120 # error "PIPE_BUF >= IOBUF_SIZE"
 121 #endif
 122
 123 #define HEADER_READ_TIMEOUT 60
 124
 125 static const char default_path_httpd_conf[] ALIGN1 = "/etc";
 126 static const char httpd_conf[] ALIGN1 = "httpd.conf";
 127 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
 128
 129 typedef struct has_next_ptr {
 130         struct has_next_ptr *next;
 131 } has_next_ptr;
 132
 133 /* Must have "next" as a first member */
 134 typedef struct Htaccess {
 135         struct Htaccess *next;
 136         char *after_colon;
 137         char before_colon[1];  /* really bigger, must be last */
 138 } Htaccess;
 139
 140 /* Must have "next" as a first member */
 141 typedef struct Htaccess_IP {
 142         struct Htaccess_IP *next;
 143         unsigned ip;
 144         unsigned mask;
 145         int allow_deny;
 146 } Htaccess_IP;
 147
 148 /* Must have "next" as a first member */
 149 typedef struct Htaccess_Proxy {
 150         struct Htaccess_Proxy *next;
 151         char *url_from;
 152         char *host_port;
 153         char *url_to;
 154 } Htaccess_Proxy;
 155
 156 enum {
 157         HTTP_OK = 200,
 158         HTTP_PARTIAL_CONTENT = 206,
 159         HTTP_MOVED_TEMPORARILY = 302,
 160         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
 161         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
 162         HTTP_NOT_FOUND = 404,
 163         HTTP_FORBIDDEN = 403,
 164         HTTP_REQUEST_TIMEOUT = 408,
 165         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
 166         HTTP_INTERNAL_SERVER_ERROR = 500,
 167         HTTP_CONTINUE = 100,
 168 #if 0   /* future use */
 169         HTTP_SWITCHING_PROTOCOLS = 101,
 170         HTTP_CREATED = 201,
 171         HTTP_ACCEPTED = 202,
 172         HTTP_NON_AUTHORITATIVE_INFO = 203,
 173         HTTP_NO_CONTENT = 204,
 174         HTTP_MULTIPLE_CHOICES = 300,
 175         HTTP_MOVED_PERMANENTLY = 301,
 176         HTTP_NOT_MODIFIED = 304,
 177         HTTP_PAYMENT_REQUIRED = 402,
 178         HTTP_BAD_GATEWAY = 502,
 179         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
 180         HTTP_RESPONSE_SETSIZE = 0xffffffff
 181 #endif
 182 };
 183
 184 static const uint16_t http_response_type[] ALIGN2 = {
 185         HTTP_OK,
 186 #if ENABLE_FEATURE_HTTPD_RANGES
 187         HTTP_PARTIAL_CONTENT,
 188 #endif
 189         HTTP_MOVED_TEMPORARILY,
 190         HTTP_REQUEST_TIMEOUT,
 191         HTTP_NOT_IMPLEMENTED,
 192 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 193         HTTP_UNAUTHORIZED,
 194 #endif
 195         HTTP_NOT_FOUND,
 196         HTTP_BAD_REQUEST,
 197         HTTP_FORBIDDEN,
 198         HTTP_INTERNAL_SERVER_ERROR,
 199 #if 0   /* not implemented */
 200         HTTP_CREATED,
 201         HTTP_ACCEPTED,
 202         HTTP_NO_CONTENT,
 203         HTTP_MULTIPLE_CHOICES,
 204         HTTP_MOVED_PERMANENTLY,
 205         HTTP_NOT_MODIFIED,
 206         HTTP_BAD_GATEWAY,
 207         HTTP_SERVICE_UNAVAILABLE,
 208 #endif
 209 };
 210
 211 static const struct {
 212         const char *name;
 213         const char *info;
 214 } http_response[ARRAY_SIZE(http_response_type)] = {
 215         { "OK", NULL },
 216 #if ENABLE_FEATURE_HTTPD_RANGES
 217         { "Partial Content", NULL },
 218 #endif
 219         { "Found", NULL },
 220         { "Request Timeout", "No request appeared within 60 seconds" },
 221         { "Not Implemented", "The requested method is not recognized" },
 222 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 223         { "Unauthorized", "" },
 224 #endif
 225         { "Not Found", "The requested URL was not found" },
 226         { "Bad Request", "Unsupported method" },
 227         { "Forbidden", ""  },
 228         { "Internal Server Error", "Internal Server Error" },
 229 #if 0   /* not implemented */
 230         { "Created" },
 231         { "Accepted" },
 232         { "No Content" },
 233         { "Multiple Choices" },
 234         { "Moved Permanently" },
 235         { "Not Modified" },
 236         { "Bad Gateway", "" },
 237         { "Service Unavailable", "" },
 238 #endif
 239 };
 240
 241
 242 struct globals {
 243         int verbose;            /* must be int (used by getopt32) */
 244         smallint flg_deny_all;
 245
 246         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
 247         time_t last_mod;
 248         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
 249         const char *bind_addr_or_port;
 250
 251         const char *g_query;
 252         const char *configFile;
 253         const char *home_httpd;
 254         const char *index_page;
 255
 256         const char *found_mime_type;
 257         const char *found_moved_temporarily;
 258         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 259
 260         USE_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
 261         USE_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
 262         USE_FEATURE_HTTPD_CGI(char *referer;)
 263         USE_FEATURE_HTTPD_CGI(char *user_agent;)
 264
 265         off_t file_size;        /* -1 - unknown */
 266 #if ENABLE_FEATURE_HTTPD_RANGES
 267         off_t range_start;
 268         off_t range_end;
 269         off_t range_len;
 270 #endif
 271
 272 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 273         Htaccess *g_auth;       /* config user:password lines */
 274 #endif
 275 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 276         Htaccess *mime_a;       /* config mime types */
 277 #endif
 278 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 279         Htaccess *script_i;     /* config script interpreters */
 280 #endif
 281         char *iobuf;            /* [IOBUF_SIZE] */
 282 #define hdr_buf bb_common_bufsiz1
 283         char *hdr_ptr;
 284         int hdr_cnt;
 285 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 286         const char *http_error_page[ARRAY_SIZE(http_response_type)];
 287 #endif
 288 #if ENABLE_FEATURE_HTTPD_PROXY
 289         Htaccess_Proxy *proxy;
 290 #endif
 291 };
 292 #define G (*ptr_to_globals)
 293 #define verbose           (G.verbose          )
 294 #define flg_deny_all      (G.flg_deny_all     )
 295 #define rmt_ip            (G.rmt_ip           )
 296 #define bind_addr_or_port (G.bind_addr_or_port)
 297 #define g_query           (G.g_query          )
 298 #define configFile        (G.configFile       )
 299 #define home_httpd        (G.home_httpd       )
 300 #define index_page        (G.index_page       )
 301 #define found_mime_type   (G.found_mime_type  )
 302 #define found_moved_temporarily (G.found_moved_temporarily)
 303 #define last_mod          (G.last_mod         )
 304 #define ip_a_d            (G.ip_a_d           )
 305 #define g_realm           (G.g_realm          )
 306 #define remoteuser        (G.remoteuser       )
 307 #define referer           (G.referer          )
 308 #define user_agent        (G.user_agent       )
 309 #define file_size         (G.file_size        )
 310 #if ENABLE_FEATURE_HTTPD_RANGES
 311 #define range_start       (G.range_start      )
 312 #define range_end         (G.range_end        )
 313 #define range_len         (G.range_len        )
 314 #endif
 315 #define rmt_ip_str        (G.rmt_ip_str       )
 316 #define g_auth            (G.g_auth           )
 317 #define mime_a            (G.mime_a           )
 318 #define script_i          (G.script_i         )
 319 #define iobuf             (G.iobuf            )
 320 #define hdr_ptr           (G.hdr_ptr          )
 321 #define hdr_cnt           (G.hdr_cnt          )
 322 #define http_error_page   (G.http_error_page  )
 323 #define proxy             (G.proxy            )
 324 #define INIT_G() do { \
 325         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 326         USE_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
 327         bind_addr_or_port = "80"; \
 328         index_page = "index.html"; \
 329         file_size = -1; \
 330 } while (0)
 331
 332 #if !ENABLE_FEATURE_HTTPD_RANGES
 333 enum {
 334         range_start = 0,
 335         range_end = MAXINT(off_t) - 1,
 336         range_len = MAXINT(off_t),
 337 };
 338 #endif
 339
 340
 341 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
 342
 343 /* Prototypes */
 344 enum {
 345         SEND_HEADERS     = (1 << 0),
 346         SEND_BODY        = (1 << 1),
 347         SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
 348 };
 349 static void send_file_and_exit(const char *url, int what) ATTRIBUTE_NORETURN;
 350
 351 static void free_llist(has_next_ptr **pptr)
 352 {
 353         has_next_ptr *cur = *pptr;
 354         while (cur) {
 355                 has_next_ptr *t = cur;
 356                 cur = cur->next;
 357                 free(t);
 358         }
 359         *pptr = NULL;
 360 }
 361
 362 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 363  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 364  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 365 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 366 {
 367         free_llist((has_next_ptr**)pptr);
 368 }
 369 #endif
 370
 371 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 372 {
 373         free_llist((has_next_ptr**)pptr);
 374 }
 375
 376 /* Returns presumed mask width in bits or < 0 on error.
 377  * Updates strp, stores IP at provided pointer */
 378 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 379 {
 380         const char *p = *strp;
 381         int auto_mask = 8;
 382         unsigned ip = 0;
 383         int j;
 384
 385         if (*p == '/')
 386                 return -auto_mask;
 387
 388         for (j = 0; j < 4; j++) {
 389                 unsigned octet;
 390
 391                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
 392                         return -auto_mask;
 393                 octet = 0;
 394                 while (*p >= '0' && *p <= '9') {
 395                         octet *= 10;
 396                         octet += *p - '0';
 397                         if (octet > 255)
 398                                 return -auto_mask;
 399                         p++;
 400                 }
 401                 if (*p == '.')
 402                         p++;
 403                 if (*p != '/' && *p)
 404                         auto_mask += 8;
 405                 ip = (ip << 8) | octet;
 406         }
 407         if (*p) {
 408                 if (*p != endc)
 409                         return -auto_mask;
 410                 p++;
 411                 if (*p == '\0')
 412                         return -auto_mask;
 413         }
 414         *ipp = ip;
 415         *strp = p;
 416         return auto_mask;
 417 }
 418
 419 /* Returns 0 on success. Stores IP and mask at provided pointers */
 420 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 421 {
 422         int i;
 423         unsigned mask;
 424         char *p;
 425
 426         i = scan_ip(&str, ipp, '/');
 427         if (i < 0)
 428                 return i;
 429
 430         if (*str) {
 431                 /* there is /xxx after dotted-IP address */
 432                 i = bb_strtou(str, &p, 10);
 433                 if (*p == '.') {
 434                         /* 'xxx' itself is dotted-IP mask, parse it */
 435                         /* (return 0 (success) only if it has N.N.N.N form) */
 436                         return scan_ip(&str, maskp, '\0') - 32;
 437                 }
 438                 if (*p)
 439                         return -1;
 440         }
 441
 442         if (i > 32)
 443                 return -1;
 444
 445         if (sizeof(unsigned) == 4 && i == 32) {
 446                 /* mask >>= 32 below may not work */
 447                 mask = 0;
 448         } else {
 449                 mask = 0xffffffff;
 450                 mask >>= i;
 451         }
 452         /* i == 0 -> *maskp = 0x00000000
 453          * i == 1 -> *maskp = 0x80000000
 454          * i == 4 -> *maskp = 0xf0000000
 455          * i == 31 -> *maskp = 0xfffffffe
 456          * i == 32 -> *maskp = 0xffffffff */
 457         *maskp = (uint32_t)(~mask);
 458         return 0;
 459 }
 460
 461 /*
 462  * Parse configuration file into in-memory linked list.
 463  *
 464  * The first non-white character is examined to determine if the config line
 465  * is one of the following:
 466  *    .ext:mime/type   # new mime type not compiled into httpd
 467  *    [adAD]:from      # ip address allow/deny, * for wildcard
 468  *    /path:user:pass  # username/password
 469  *    Ennn:error.html  # error page for status nnn
 470  *    P:/url:[http://]hostname[:port]/new/path # reverse proxy
 471  *
 472  * Any previous IP rules are discarded.
 473  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
 474  * are also discarded.  That is, previous settings are retained if flag is
 475  * SUBDIR_PARSE.
 476  * Error pages are only parsed on the main config file.
 477  *
 478  * path   Path where to look for httpd.conf (without filename).
 479  * flag   Type of the parse request.
 480  */
 481 /* flag */
 482 #define FIRST_PARSE          0
 483 #define SUBDIR_PARSE         1
 484 #define SIGNALED_PARSE       2
 485 #define FIND_FROM_HTTPD_ROOT 3
 486 static void parse_conf(const char *path, int flag)
 487 {
 488         FILE *f;
 489 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 490         Htaccess *prev;
 491 #endif
 492 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 493  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 494  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 495         Htaccess *cur;
 496 #endif
 497         const char *cf = configFile;
 498         char buf[160];
 499         char *p0;
 500         char *c, *p;
 501         Htaccess_IP *pip;
 502
 503         /* discard old rules */
 504         free_Htaccess_IP_list(&ip_a_d);
 505         flg_deny_all = 0;
 506 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 507  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 508  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 509         /* retain previous auth and mime config only for subdir parse */
 510         if (flag != SUBDIR_PARSE) {
 511 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 512                 free_Htaccess_list(&g_auth);
 513 #endif
 514 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 515                 free_Htaccess_list(&mime_a);
 516 #endif
 517 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 518                 free_Htaccess_list(&script_i);
 519 #endif
 520         }
 521 #endif
 522
 523         if (flag == SUBDIR_PARSE || cf == NULL) {
 524                 cf = alloca(strlen(path) + sizeof(httpd_conf) + 2);
 525                 sprintf((char *)cf, "%s/%s", path, httpd_conf);
 526         }
 527
 528         while ((f = fopen(cf, "r")) == NULL) {
 529                 if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) {
 530                         /* config file not found, no changes to config */
 531                         return;
 532                 }
 533                 if (configFile && flag == FIRST_PARSE) /* if -c option given */
 534                         bb_simple_perror_msg_and_die(cf);
 535                 flag = FIND_FROM_HTTPD_ROOT;
 536                 cf = httpd_conf;
 537         }
 538
 539 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 540         prev = g_auth;
 541 #endif
 542         /* This could stand some work */
 543         while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) {
 544                 c = NULL;
 545                 for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) {
 546                         if (!isspace(*p0)) {
 547                                 *p++ = *p0;
 548                                 if (*p0 == ':' && c == NULL)
 549                                         c = p;
 550                         }
 551                 }
 552                 *p = '\0';
 553
 554                 /* test for empty or strange line */
 555                 if (c == NULL || *c == '\0')
 556                         continue;
 557                 p0 = buf;
 558                 if (*p0 == 'd')
 559                         *p0 = 'D';
 560                 if (*c == '*') {
 561                         if (*p0 == 'D') {
 562                                 /* memorize deny all */
 563                                 flg_deny_all = 1;
 564                         }
 565                         /* skip default other "word:*" config lines */
 566                         continue;
 567                 }
 568
 569                 if (*p0 == 'a')
 570                         *p0 = 'A';
 571                 if (*p0 == 'A' || *p0 == 'D') {
 572                         /* storing current config IP line */
 573                         pip = xzalloc(sizeof(Htaccess_IP));
 574                         if (pip) {
 575                                 if (scan_ip_mask(c, &(pip->ip), &(pip->mask))) {
 576                                         /* syntax IP{/mask} error detected, protect all */
 577                                         *p0 = 'D';
 578                                         pip->mask = 0;
 579                                 }
 580                                 pip->allow_deny = *p0;
 581                                 if (*p0 == 'D') {
 582                                         /* Deny:from_IP move top */
 583                                         pip->next = ip_a_d;
 584                                         ip_a_d = pip;
 585                                 } else {
 586                                         /* add to bottom A:form_IP config line */
 587                                         Htaccess_IP *prev_IP = ip_a_d;
 588
 589                                         if (prev_IP == NULL) {
 590                                                 ip_a_d = pip;
 591                                         } else {
 592                                                 while (prev_IP->next)
 593                                                         prev_IP = prev_IP->next;
 594                                                 prev_IP->next = pip;
 595                                         }
 596                                 }
 597                         }
 598                         continue;
 599                 }
 600
 601 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 602                 if (flag == FIRST_PARSE && *p0 == 'E') {
 603                         unsigned i;
 604                         /* error status code */
 605                         int status = atoi(++p0);
 606                         /* c already points at the character following ':' in parse loop */
 607                         /* c = strchr(p0, ':'); c++; */
 608                         if (status < HTTP_CONTINUE) {
 609                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
 610                                 continue;
 611                         }
 612
 613                         /* then error page; find matching status */
 614                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 615                                 if (http_response_type[i] == status) {
 616                                         // We chdir to home_httpd, thus no need to
 617                                         // concat_path_file(home_httpd, c)
 618                                         //if (c[0] == '/' || home_httpd[0] != '/')
 619                                                 http_error_page[i] = xstrdup(c);
 620                                         //else
 621                                         //      http_error_page[i] = concat_path_file(home_httpd, c);
 622                                         break;
 623                                 }
 624                         }
 625                         continue;
 626                 }
 627 #endif
 628
 629 #if ENABLE_FEATURE_HTTPD_PROXY
 630                 if (flag == FIRST_PARSE && *p0 == 'P') {
 631                         /* P:/url:[http://]hostname[:port]/new/path */
 632                         char *url_from, *host_port, *url_to;
 633                         Htaccess_Proxy *proxy_entry;
 634
 635                         url_from = c;
 636                         host_port = strchr(c, ':');
 637                         if (host_port == NULL) {
 638                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
 639                                 continue;
 640                         }
 641                         *host_port++ = '\0';
 642                         if (strncmp(host_port, "http://", 7) == 0)
 643                                 host_port += 7;
 644                         if (*host_port == '\0') {
 645                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
 646                                 continue;
 647                         }
 648                         url_to = strchr(host_port, '/');
 649                         if (url_to == NULL) {
 650                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
 651                                 continue;
 652                         }
 653                         *url_to = '\0';
 654                         proxy_entry = xzalloc(sizeof(Htaccess_Proxy));
 655                         proxy_entry->url_from = xstrdup(url_from);
 656                         proxy_entry->host_port = xstrdup(host_port);
 657                         *url_to = '/';
 658                         proxy_entry->url_to = xstrdup(url_to);
 659                         proxy_entry->next = proxy;
 660                         proxy = proxy_entry;
 661                         continue;
 662                 }
 663 #endif
 664
 665 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 666                 if (*p0 == '/') {
 667                         /* make full path from httpd root / current_path / config_line_path */
 668                         cf = (flag == SUBDIR_PARSE ? path : "");
 669                         p0 = xmalloc(strlen(cf) + (c - buf) + 2 + strlen(c));
 670                         c[-1] = '\0';
 671                         sprintf(p0, "/%s%s", cf, buf);
 672
 673                         /* another call bb_simplify_path */
 674                         cf = p = p0;
 675
 676                         do {
 677                                 if (*p == '/') {
 678                                         if (*cf == '/') {    /* skip duplicate (or initial) slash */
 679                                                 continue;
 680                                         }
 681                                         if (*cf == '.') {
 682                                                 if (cf[1] == '/' || cf[1] == '\0') { /* remove extra '.' */
 683                                                         continue;
 684                                                 }
 685                                                 if ((cf[1] == '.') && (cf[2] == '/' || cf[2] == '\0')) {
 686                                                         ++cf;
 687                                                         if (p > p0) {
 688                                                                 while (*--p != '/') /* omit previous dir */;
 689                                                         }
 690                                                         continue;
 691                                                 }
 692                                         }
 693                                 }
 694                                 *++p = *cf;
 695                         } while (*++cf);
 696
 697                         if ((p == p0) || (*p != '/')) {      /* not a trailing slash */
 698                                 ++p;                             /* so keep last character */
 699                         }
 700                         *p = ':';
 701                         strcpy(p + 1, c);
 702                 }
 703 #endif
 704
 705                 if (*p0 == 'I') {
 706                         index_page = xstrdup(c);
 707                         continue;
 708                 }
 709
 710 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 711  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 712  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 713                 /* storing current config line */
 714                 cur = xzalloc(sizeof(Htaccess) + strlen(p0));
 715                 cf = strcpy(cur->before_colon, p0);
 716 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 717                 if (*p0 == '/')
 718                         free(p0);
 719 #endif
 720                 c = strchr(cf, ':');
 721                 *c++ = '\0';
 722                 cur->after_colon = c;
 723 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 724                 if (*cf == '.') {
 725                         /* config .mime line move top for overwrite previous */
 726                         cur->next = mime_a;
 727                         mime_a = cur;
 728                         continue;
 729                 }
 730 #endif
 731 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 732                 if (*cf == '*' && cf[1] == '.') {
 733                         /* config script interpreter line move top for overwrite previous */
 734                         cur->next = script_i;
 735                         script_i = cur;
 736                         continue;
 737                 }
 738 #endif
 739 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 740                 if (prev == NULL) {
 741                         /* first line */
 742                         g_auth = prev = cur;
 743                 } else {
 744                         /* sort path, if current length eq or bigger then move up */
 745                         Htaccess *prev_hti = g_auth;
 746                         size_t l = strlen(cf);
 747                         Htaccess *hti;
 748
 749                         for (hti = prev_hti; hti; hti = hti->next) {
 750                                 if (l >= strlen(hti->before_colon)) {
 751                                         /* insert before hti */
 752                                         cur->next = hti;
 753                                         if (prev_hti != hti) {
 754                                                 prev_hti->next = cur;
 755                                         } else {
 756                                                 /* insert as top */
 757                                                 g_auth = cur;
 758                                         }
 759                                         break;
 760                                 }
 761                                 if (prev_hti != hti)
 762                                         prev_hti = prev_hti->next;
 763                         }
 764                         if (!hti) {       /* not inserted, add to bottom */
 765                                 prev->next = cur;
 766                                 prev = cur;
 767                         }
 768                 }
 769 #endif /* BASIC_AUTH */
 770 #endif /* BASIC_AUTH || MIME_TYPES || SCRIPT_INTERPR */
 771          } /* while (fgets) */
 772          fclose(f);
 773 }
 774
 775 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
 776 /*
 777  * Given a string, html-encode special characters.
 778  * This is used for the -e command line option to provide an easy way
 779  * for scripts to encode result data without confusing browsers.  The
 780  * returned string pointer is memory allocated by malloc().
 781  *
 782  * Returns a pointer to the encoded string (malloced).
 783  */
 784 static char *encodeString(const char *string)
 785 {
 786         /* take the simple route and encode everything */
 787         /* could possibly scan once to get length.     */
 788         int len = strlen(string);
 789         char *out = xmalloc(len * 6 + 1);
 790         char *p = out;
 791         char ch;
 792
 793         while ((ch = *string++)) {
 794                 /* very simple check for what to encode */
 795                 if (isalnum(ch))
 796                         *p++ = ch;
 797                 else
 798                         p += sprintf(p, "&#%d;", (unsigned char) ch);
 799         }
 800         *p = '\0';
 801         return out;
 802 }
 803 #endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
 804
 805 /*
 806  * Given a URL encoded string, convert it to plain ascii.
 807  * Since decoding always makes strings smaller, the decode is done in-place.
 808  * Thus, callers should xstrdup() the argument if they do not want the
 809  * argument modified.  The return is the original pointer, allowing this
 810  * function to be easily used as arguments to other functions.
 811  *
 812  * string    The first string to decode.
 813  * option_d  1 if called for httpd -d
 814  *
 815  * Returns a pointer to the decoded string (same as input).
 816  */
 817 static unsigned hex_to_bin(unsigned char c)
 818 {
 819         unsigned v;
 820
 821         v = c - '0';
 822         if (v <= 9)
 823                 return v;
 824         /* c | 0x20: letters to lower case, non-letters
 825          * to (potentially different) non-letters */
 826         v = (unsigned)(c | 0x20) - 'a';
 827         if (v <= 5)
 828                 return v + 10;
 829         return ~0;
 830 }
 831 /* For testing:
 832 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
 833 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 834 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 835 */
 836 static char *decodeString(char *orig, int option_d)
 837 {
 838         /* note that decoded string is always shorter than original */
 839         char *string = orig;
 840         char *ptr = string;
 841         char c;
 842
 843         while ((c = *ptr++) != '\0') {
 844                 unsigned v;
 845
 846                 if (option_d && c == '+') {
 847                         *string++ = ' ';
 848                         continue;
 849                 }
 850                 if (c != '%') {
 851                         *string++ = c;
 852                         continue;
 853                 }
 854                 v = hex_to_bin(ptr[0]);
 855                 if (v > 15) {
 856  bad_hex:
 857                         if (!option_d)
 858                                 return NULL;
 859                         *string++ = '%';
 860                         continue;
 861                 }
 862                 v = (v * 16) | hex_to_bin(ptr[1]);
 863                 if (v > 255)
 864                         goto bad_hex;
 865                 if (!option_d && (v == '/' || v == '\0')) {
 866                         /* caller takes it as indication of invalid
 867                          * (dangerous wrt exploits) chars */
 868                         return orig + 1;
 869                 }
 870                 *string++ = v;
 871                 ptr += 2;
 872         }
 873         *string = '\0';
 874         return orig;
 875 }
 876
 877 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 878 /*
 879  * Decode a base64 data stream as per rfc1521.
 880  * Note that the rfc states that non base64 chars are to be ignored.
 881  * Since the decode always results in a shorter size than the input,
 882  * it is OK to pass the input arg as an output arg.
 883  * Parameter: a pointer to a base64 encoded string.
 884  * Decoded data is stored in-place.
 885  */
 886 static void decodeBase64(char *Data)
 887 {
 888         const unsigned char *in = (const unsigned char *)Data;
 889         /* The decoded size will be at most 3/4 the size of the encoded */
 890         unsigned ch = 0;
 891         int i = 0;
 892
 893         while (*in) {
 894                 int t = *in++;
 895
 896                 if (t >= '0' && t <= '9')
 897                         t = t - '0' + 52;
 898                 else if (t >= 'A' && t <= 'Z')
 899                         t = t - 'A';
 900                 else if (t >= 'a' && t <= 'z')
 901                         t = t - 'a' + 26;
 902                 else if (t == '+')
 903                         t = 62;
 904                 else if (t == '/')
 905                         t = 63;
 906                 else if (t == '=')
 907                         t = 0;
 908                 else
 909                         continue;
 910
 911                 ch = (ch << 6) | t;
 912                 i++;
 913                 if (i == 4) {
 914                         *Data++ = (char) (ch >> 16);
 915                         *Data++ = (char) (ch >> 8);
 916                         *Data++ = (char) ch;
 917                         i = 0;
 918                 }
 919         }
 920         *Data = '\0';
 921 }
 922 #endif
 923
 924 /*
 925  * Create a listen server socket on the designated port.
 926  */
 927 static int openServer(void)
 928 {
 929         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 930         if (!errno && n && n <= 0xffff)
 931                 n = create_and_bind_stream_or_die(NULL, n);
 932         else
 933                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 934         xlisten(n, 9);
 935         return n;
 936 }
 937
 938 /*
 939  * Log the connection closure and exit.
 940  */
 941 static void log_and_exit(void) ATTRIBUTE_NORETURN;
 942 static void log_and_exit(void)
 943 {
 944         /* Paranoia. IE said to be buggy. It may send some extra data
 945          * or be confused by us just exiting without SHUT_WR. Oh well. */
 946         shutdown(1, SHUT_WR);
 947         ndelay_on(0);
 948         while (read(0, iobuf, IOBUF_SIZE) > 0)
 949                 continue;
 950
 951         if (verbose > 2)
 952                 bb_error_msg("closed");
 953         _exit(xfunc_error_retval);
 954 }
 955
 956 /*
 957  * Create and send HTTP response headers.
 958  * The arguments are combined and sent as one write operation.  Note that
 959  * IE will puke big-time if the headers are not sent in one packet and the
 960  * second packet is delayed for any reason.
 961  * responseNum - the result code to send.
 962  */
 963 static void send_headers(int responseNum)
 964 {
 965         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 966
 967         const char *responseString = "";
 968         const char *infoString = NULL;
 969         const char *mime_type;
 970 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 971         const char *error_page = NULL;
 972 #endif
 973         unsigned i;
 974         time_t timer = time(0);
 975         char tmp_str[80];
 976         int len;
 977
 978         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 979                 if (http_response_type[i] == responseNum) {
 980                         responseString = http_response[i].name;
 981                         infoString = http_response[i].info;
 982 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 983                         error_page = http_error_page[i];
 984 #endif
 985                         break;
 986                 }
 987         }
 988         /* error message is HTML */
 989         mime_type = responseNum == HTTP_OK ?
 990                                 found_mime_type : "text/html";
 991
 992         if (verbose)
 993                 bb_error_msg("response:%u", responseNum);
 994
 995         /* emit the current date */
 996         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
 997         len = sprintf(iobuf,
 998                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
 999                         "Date: %s\r\nConnection: close\r\n",
1000                         responseNum, responseString, mime_type, tmp_str);
1001
1002 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1003         if (responseNum == HTTP_UNAUTHORIZED) {
1004                 len += sprintf(iobuf + len,
1005                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
1006                                 g_realm);
1007         }
1008 #endif
1009         if (responseNum == HTTP_MOVED_TEMPORARILY) {
1010                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
1011                                 found_moved_temporarily,
1012                                 (g_query ? "?" : ""),
1013                                 (g_query ? g_query : ""));
1014         }
1015
1016 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1017         if (error_page && access(error_page, R_OK) == 0) {
1018                 strcat(iobuf, "\r\n");
1019                 len += 2;
1020
1021                 if (DEBUG)
1022                         fprintf(stderr, "headers: '%s'\n", iobuf);
1023                 full_write(1, iobuf, len);
1024                 if (DEBUG)
1025                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1026                 return send_file_and_exit(error_page, SEND_BODY);
1027         }
1028 #endif
1029
1030         if (file_size != -1) {    /* file */
1031                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1032 #if ENABLE_FEATURE_HTTPD_RANGES
1033                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1034                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"d-%"OFF_FMT"d/%"OFF_FMT"d\r\n",
1035                                         range_start,
1036                                         range_end,
1037                                         file_size);
1038                         file_size = range_end - range_start + 1;
1039                 }
1040 #endif
1041                 len += sprintf(iobuf + len,
1042 #if ENABLE_FEATURE_HTTPD_RANGES
1043                         "Accept-Ranges: bytes\r\n"
1044 #endif
1045                         "Last-Modified: %s\r\n%s %"OFF_FMT"d\r\n",
1046                                 tmp_str,
1047                                 "Content-length:",
1048                                 file_size
1049                 );
1050         }
1051         iobuf[len++] = '\r';
1052         iobuf[len++] = '\n';
1053         if (infoString) {
1054                 len += sprintf(iobuf + len,
1055                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1056                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1057                                 responseNum, responseString,
1058                                 responseNum, responseString, infoString);
1059         }
1060         if (DEBUG)
1061                 fprintf(stderr, "headers: '%s'\n", iobuf);
1062         if (full_write(1, iobuf, len) != len) {
1063                 if (verbose > 1)
1064                         bb_perror_msg("error");
1065                 log_and_exit();
1066         }
1067 }
1068
1069 static void send_headers_and_exit(int responseNum) ATTRIBUTE_NORETURN;
1070 static void send_headers_and_exit(int responseNum)
1071 {
1072         send_headers(responseNum);
1073         log_and_exit();
1074 }
1075
1076 /*
1077  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1078  * '\n' is replaced with NUL.
1079  * Return number of characters read or 0 if nothing is read
1080  * ('\r' and '\n' are not counted).
1081  * Data is returned in iobuf.
1082  */
1083 static int get_line(void)
1084 {
1085         int count = 0;
1086         char c;
1087
1088         while (1) {
1089                 if (hdr_cnt <= 0) {
1090                         hdr_cnt = safe_read(0, hdr_buf, sizeof(hdr_buf));
1091                         if (hdr_cnt <= 0)
1092                                 break;
1093                         hdr_ptr = hdr_buf;
1094                 }
1095                 iobuf[count] = c = *hdr_ptr++;
1096                 hdr_cnt--;
1097
1098                 if (c == '\r')
1099                         continue;
1100                 if (c == '\n') {
1101                         iobuf[count] = '\0';
1102                         return count;
1103                 }
1104                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1105                         count++;
1106         }
1107         return count;
1108 }
1109
1110 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1111
1112 /* gcc 4.2.1 fares better with NOINLINE */
1113 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) ATTRIBUTE_NORETURN;
1114 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1115 {
1116         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1117         struct pollfd pfd[3];
1118         int out_cnt; /* we buffer a bit of initial CGI output */
1119         int count;
1120
1121         /* iobuf is used for CGI -> network data,
1122          * hdr_buf is for network -> CGI data (POSTDATA) */
1123
1124         /* If CGI dies, we still want to correctly finish reading its output
1125          * and send it to the peer. So please no SIGPIPEs! */
1126         signal(SIGPIPE, SIG_IGN);
1127
1128         // We inconsistently handle a case when more POSTDATA from network
1129         // is coming than we expected. We may give *some part* of that
1130         // extra data to CGI.
1131
1132         //if (hdr_cnt > post_len) {
1133         //      /* We got more POSTDATA from network than we expected */
1134         //      hdr_cnt = post_len;
1135         //}
1136         post_len -= hdr_cnt;
1137         /* post_len - number of POST bytes not yet read from network */
1138
1139         /* NB: breaking out of this loop jumps to log_and_exit() */
1140         out_cnt = 0;
1141         while (1) {
1142                 memset(pfd, 0, sizeof(pfd));
1143
1144                 pfd[FROM_CGI].fd = fromCgi_rd;
1145                 pfd[FROM_CGI].events = POLLIN;
1146
1147                 if (toCgi_wr) {
1148                         pfd[TO_CGI].fd = toCgi_wr;
1149                         if (hdr_cnt > 0) {
1150                                 pfd[TO_CGI].events = POLLOUT;
1151                         } else if (post_len > 0) {
1152                                 pfd[0].events = POLLIN;
1153                         } else {
1154                                 /* post_len <= 0 && hdr_cnt <= 0:
1155                                  * no more POST data to CGI,
1156                                  * let CGI see EOF on CGI's stdin */
1157                                 close(toCgi_wr);
1158                                 toCgi_wr = 0;
1159                         }
1160                 }
1161
1162                 /* Now wait on the set of sockets */
1163                 count = safe_poll(pfd, 3, -1);
1164                 if (count <= 0) {
1165 #if 0
1166                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1167                                 /* Weird. CGI didn't exit and no fd's
1168                                  * are ready, yet poll returned?! */
1169                                 continue;
1170                         }
1171                         if (DEBUG && WIFEXITED(status))
1172                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1173                         if (DEBUG && WIFSIGNALED(status))
1174                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1175 #endif
1176                         break;
1177                 }
1178
1179                 if (pfd[TO_CGI].revents) {
1180                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1181                         /* Have data from peer and can write to CGI */
1182                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1183                         /* Doesn't happen, we dont use nonblocking IO here
1184                          *if (count < 0 && errno == EAGAIN) {
1185                          *      ...
1186                          *} else */
1187                         if (count > 0) {
1188                                 hdr_ptr += count;
1189                                 hdr_cnt -= count;
1190                         } else {
1191                                 /* EOF/broken pipe to CGI, stop piping POST data */
1192                                 hdr_cnt = post_len = 0;
1193                         }
1194                 }
1195
1196                 if (pfd[0].revents) {
1197                         /* post_len > 0 && hdr_cnt == 0 here */
1198                         /* We expect data, prev data portion is eaten by CGI
1199                          * and there *is* data to read from the peer
1200                          * (POSTDATA) */
1201                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1202                         //count = safe_read(0, hdr_buf, count);
1203                         count = safe_read(0, hdr_buf, sizeof(hdr_buf));
1204                         if (count > 0) {
1205                                 hdr_cnt = count;
1206                                 hdr_ptr = hdr_buf;
1207                                 post_len -= count;
1208                         } else {
1209                                 /* no more POST data can be read */
1210                                 post_len = 0;
1211                         }
1212                 }
1213
1214                 if (pfd[FROM_CGI].revents) {
1215                         /* There is something to read from CGI */
1216                         char *rbuf = iobuf;
1217
1218                         /* Are we still buffering CGI output? */
1219                         if (out_cnt >= 0) {
1220                                 /* HTTP_200[] has single "\r\n" at the end.
1221                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1222                                  * CGI scripts MUST send their own header terminated by
1223                                  * empty line, then data. That's why we have only one
1224                                  * <cr><lf> pair here. We will output "200 OK" line
1225                                  * if needed, but CGI still has to provide blank line
1226                                  * between header and body */
1227
1228                                 /* Must use safe_read, not full_read, because
1229                                  * CGI may output a few first bytes and then wait
1230                                  * for POSTDATA without closing stdout.
1231                                  * With full_read we may wait here forever. */
1232                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1233                                 if (count <= 0) {
1234                                         /* eof (or error) and there was no "HTTP",
1235                                          * so write it, then write received data */
1236                                         if (out_cnt) {
1237                                                 full_write(1, HTTP_200, sizeof(HTTP_200)-1);
1238                                                 full_write(1, rbuf, out_cnt);
1239                                         }
1240                                         break; /* CGI stdout is closed, exiting */
1241                                 }
1242                                 out_cnt += count;
1243                                 count = 0;
1244                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1245                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1246                                         /* send "HTTP/1.0 " */
1247                                         if (full_write(1, HTTP_200, 9) != 9)
1248                                                 break;
1249                                         rbuf += 8; /* skip "Status: " */
1250                                         count = out_cnt - 8;
1251                                         out_cnt = -1; /* buffering off */
1252                                 } else if (out_cnt >= 4) {
1253                                         /* Did CGI add "HTTP"? */
1254                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1255                                                 /* there is no "HTTP", do it ourself */
1256                                                 if (full_write(1, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1257                                                         break;
1258                                         }
1259                                         /* Commented out:
1260                                         if (!strstr(rbuf, "ontent-")) {
1261                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1262                                         }
1263                                          * Counter-example of valid CGI without Content-type:
1264                                          * echo -en "HTTP/1.0 302 Found\r\n"
1265                                          * echo -en "Location: http://www.busybox.net\r\n"
1266                                          * echo -en "\r\n"
1267                                          */
1268                                         count = out_cnt;
1269                                         out_cnt = -1; /* buffering off */
1270                                 }
1271                         } else {
1272                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1273                                 if (count <= 0)
1274                                         break;  /* eof (or error) */
1275                         }
1276                         if (full_write(1, rbuf, count) != count)
1277                                 break;
1278                         if (DEBUG)
1279                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1280                 } /* if (pfd[FROM_CGI].revents) */
1281         } /* while (1) */
1282         log_and_exit();
1283 }
1284 #endif
1285
1286 #if ENABLE_FEATURE_HTTPD_CGI
1287
1288 static void setenv1(const char *name, const char *value)
1289 {
1290         setenv(name, value ? value : "", 1);
1291 }
1292
1293 /*
1294  * Spawn CGI script, forward CGI's stdin/out <=> network
1295  *
1296  * Environment variables are set up and the script is invoked with pipes
1297  * for stdin/stdout.  If a POST is being done the script is fed the POST
1298  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1299  *
1300  * Parameters:
1301  * const char *url              The requested URL (with leading /).
1302  * int post_len                 Length of the POST body.
1303  * const char *cookie           For set HTTP_COOKIE.
1304  * const char *content_type     For set CONTENT_TYPE.
1305  */
1306 static void send_cgi_and_exit(
1307                 const char *url,
1308                 const char *request,
1309                 int post_len,
1310                 const char *cookie,
1311                 const char *content_type) ATTRIBUTE_NORETURN;
1312 static void send_cgi_and_exit(
1313                 const char *url,
1314                 const char *request,
1315                 int post_len,
1316                 const char *cookie,
1317                 const char *content_type)
1318 {
1319         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1320         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1321         char *script;
1322         int pid;
1323
1324         /* Make a copy. NB: caller guarantees:
1325          * url[0] == '/', url[1] != '/' */
1326         url = xstrdup(url);
1327
1328         /*
1329          * We are mucking with environment _first_ and then vfork/exec,
1330          * this allows us to use vfork safely. Parent doesn't care about
1331          * these environment changes anyway.
1332          */
1333
1334         /* Check for [dirs/]script.cgi/PATH_INFO */
1335         script = (char*)url;
1336         while ((script = strchr(script + 1, '/')) != NULL) {
1337                 struct stat sb;
1338
1339                 *script = '\0';
1340                 if (!is_directory(url + 1, 1, &sb)) {
1341                         /* not directory, found script.cgi/PATH_INFO */
1342                         *script = '/';
1343                         break;
1344                 }
1345                 *script = '/'; /* is directory, find next '/' */
1346         }
1347         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1348         setenv1("REQUEST_METHOD", request);
1349         if (g_query) {
1350                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1351         } else {
1352                 setenv1("REQUEST_URI", url);
1353         }
1354         if (script != NULL)
1355                 *script = '\0';         /* cut off /PATH_INFO */
1356
1357         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1358         if (home_httpd[0] == '/') {
1359                 char *fullpath = concat_path_file(home_httpd, url);
1360                 setenv1("SCRIPT_FILENAME", fullpath);
1361         }
1362         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1363         setenv1("SCRIPT_NAME", url);
1364         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1365          * QUERY_STRING: The information which follows the ? in the URL
1366          * which referenced this script. This is the query information.
1367          * It should not be decoded in any fashion. This variable
1368          * should always be set when there is query information,
1369          * regardless of command line decoding. */
1370         /* (Older versions of bbox seem to do some decoding) */
1371         setenv1("QUERY_STRING", g_query);
1372         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1373         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1374         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1375         /* Having _separate_ variables for IP and port defeats
1376          * the purpose of having socket abstraction. Which "port"
1377          * are you using on Unix domain socket?
1378          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1379          * Oh well... */
1380         {
1381                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1382                 char *cp = strrchr(p, ':');
1383                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1384                         cp = NULL;
1385                 if (cp) *cp = '\0'; /* delete :PORT */
1386                 setenv1("REMOTE_ADDR", p);
1387                 if (cp) {
1388                         *cp = ':';
1389 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1390                         setenv1("REMOTE_PORT", cp + 1);
1391 #endif
1392                 }
1393         }
1394         setenv1("HTTP_USER_AGENT", user_agent);
1395         if (post_len)
1396                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1397         if (cookie)
1398                 setenv1("HTTP_COOKIE", cookie);
1399         if (content_type)
1400                 setenv1("CONTENT_TYPE", content_type);
1401 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1402         if (remoteuser) {
1403                 setenv1("REMOTE_USER", remoteuser);
1404                 putenv((char*)"AUTH_TYPE=Basic");
1405         }
1406 #endif
1407         if (referer)
1408                 setenv1("HTTP_REFERER", referer);
1409
1410         xpiped_pair(fromCgi);
1411         xpiped_pair(toCgi);
1412
1413         pid = vfork();
1414         if (pid < 0) {
1415                 /* TODO: log perror? */
1416                 log_and_exit();
1417         }
1418
1419         if (!pid) {
1420                 /* Child process */
1421                 char *argv[3];
1422
1423                 xfunc_error_retval = 242;
1424
1425                 /* NB: close _first_, then move fds! */
1426                 close(toCgi.wr);
1427                 close(fromCgi.rd);
1428                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1429                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1430                 /* User seeing stderr output can be a security problem.
1431                  * If CGI really wants that, it can always do dup itself. */
1432                 /* dup2(1, 2); */
1433
1434                 /* Chdiring to script's dir */
1435                 script = strrchr(url, '/');
1436                 if (script != url) { /* paranoia */
1437                         *script = '\0';
1438                         if (chdir(url + 1) != 0) {
1439                                 bb_perror_msg("chdir %s", url + 1);
1440                                 goto error_execing_cgi;
1441                         }
1442                         // not needed: *script = '/';
1443                 }
1444                 script++;
1445
1446                 /* set argv[0] to name without path */
1447                 argv[0] = script;
1448                 argv[1] = NULL;
1449
1450 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1451                 {
1452                         char *suffix = strrchr(script, '.');
1453
1454                         if (suffix) {
1455                                 Htaccess *cur;
1456                                 for (cur = script_i; cur; cur = cur->next) {
1457                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1458                                                 /* found interpreter name */
1459                                                 argv[0] = cur->after_colon;
1460                                                 argv[1] = script;
1461                                                 argv[2] = NULL;
1462                                                 break;
1463                                         }
1464                                 }
1465                         }
1466                 }
1467 #endif
1468                 /* restore default signal dispositions for CGI process */
1469                 bb_signals(0
1470                         | (1 << SIGCHLD)
1471                         | (1 << SIGPIPE)
1472                         | (1 << SIGHUP)
1473                         , SIG_DFL);
1474
1475                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1476                  * without any dir components and will only match a file
1477                  * in the current directory */
1478                 execv(argv[0], argv);
1479                 if (verbose)
1480                         bb_perror_msg("exec %s", argv[0]);
1481  error_execing_cgi:
1482                 /* send to stdout
1483                  * (we are CGI here, our stdout is pumped to the net) */
1484                 send_headers_and_exit(HTTP_NOT_FOUND);
1485         } /* end child */
1486
1487         /* Parent process */
1488
1489         /* Restore variables possibly changed by child */
1490         xfunc_error_retval = 0;
1491
1492         /* Pump data */
1493         close(fromCgi.wr);
1494         close(toCgi.rd);
1495         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1496 }
1497
1498 #endif          /* FEATURE_HTTPD_CGI */
1499
1500 /*
1501  * Send a file response to a HTTP request, and exit
1502  *
1503  * Parameters:
1504  * const char *url  The requested URL (with leading /).
1505  * what             What to send (headers/body/both).
1506  */
1507 static void send_file_and_exit(const char *url, int what)
1508 {
1509         static const char *const suffixTable[] = {
1510         /* Warning: shorter equivalent suffix in one line must be first */
1511                 ".htm.html", "text/html",
1512                 ".jpg.jpeg", "image/jpeg",
1513                 ".gif",      "image/gif",
1514                 ".png",      "image/png",
1515                 ".txt.h.c.cc.cpp", "text/plain",
1516                 ".css",      "text/css",
1517                 ".wav",      "audio/wav",
1518                 ".avi",      "video/x-msvideo",
1519                 ".qt.mov",   "video/quicktime",
1520                 ".mpe.mpeg", "video/mpeg",
1521                 ".mid.midi", "audio/midi",
1522                 ".mp3",      "audio/mpeg",
1523 #if 0                        /* unpopular */
1524                 ".au",       "audio/basic",
1525                 ".pac",      "application/x-ns-proxy-autoconfig",
1526                 ".vrml.wrl", "model/vrml",
1527 #endif
1528                 NULL
1529         };
1530
1531         char *suffix;
1532         int f;
1533         const char *const *table;
1534         const char *try_suffix;
1535         ssize_t count;
1536 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1537         off_t offset;
1538 #endif
1539
1540         /* If you want to know about EPIPE below
1541          * (happens if you abort downloads from local httpd): */
1542         signal(SIGPIPE, SIG_IGN);
1543
1544         suffix = strrchr(url, '.');
1545
1546         /* If not found, set default as "application/octet-stream";  */
1547         found_mime_type = "application/octet-stream";
1548         if (suffix) {
1549 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1550                 Htaccess *cur;
1551 #endif
1552                 for (table = suffixTable; *table; table += 2) {
1553                         try_suffix = strstr(table[0], suffix);
1554                         if (try_suffix) {
1555                                 try_suffix += strlen(suffix);
1556                                 if (*try_suffix == '\0' || *try_suffix == '.') {
1557                                         found_mime_type = table[1];
1558                                         break;
1559                                 }
1560                         }
1561                 }
1562 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1563                 for (cur = mime_a; cur; cur = cur->next) {
1564                         if (strcmp(cur->before_colon, suffix) == 0) {
1565                                 found_mime_type = cur->after_colon;
1566                                 break;
1567                         }
1568                 }
1569 #endif
1570         }
1571
1572         if (DEBUG)
1573                 bb_error_msg("sending file '%s' content-type: %s",
1574                         url, found_mime_type);
1575
1576         f = open(url, O_RDONLY);
1577         if (f < 0) {
1578                 if (DEBUG)
1579                         bb_perror_msg("cannot open '%s'", url);
1580                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1581                  * IOW: it is unsafe to call send_headers_and_exit
1582                  * if what is SEND_BODY! Can recurse! */
1583                 if (what != SEND_BODY)
1584                         send_headers_and_exit(HTTP_NOT_FOUND);
1585                 log_and_exit();
1586         }
1587 #if ENABLE_FEATURE_HTTPD_RANGES
1588         if (what == SEND_BODY)
1589                 range_start = 0; /* err pages and ranges don't mix */
1590         range_len = MAXINT(off_t);
1591         if (range_start) {
1592                 if (!range_end) {
1593                         range_end = file_size - 1;
1594                 }
1595                 if (range_end < range_start
1596                  || lseek(f, range_start, SEEK_SET) != range_start
1597                 ) {
1598                         lseek(f, 0, SEEK_SET);
1599                         range_start = 0;
1600                 } else {
1601                         range_len = range_end - range_start + 1;
1602                         send_headers(HTTP_PARTIAL_CONTENT);
1603                         what = SEND_BODY;
1604                 }
1605         }
1606 #endif
1607
1608         if (what & SEND_HEADERS)
1609                 send_headers(HTTP_OK);
1610
1611 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1612         offset = range_start;
1613         do {
1614                 /* sz is rounded down to 64k */
1615                 ssize_t sz = MAXINT(ssize_t) - 0xffff;
1616                 USE_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1617                 count = sendfile(1, f, &offset, sz);
1618                 if (count < 0) {
1619                         if (offset == range_start)
1620                                 goto fallback;
1621                         goto fin;
1622                 }
1623                 USE_FEATURE_HTTPD_RANGES(range_len -= sz;)
1624         } while (count > 0 && range_len);
1625         log_and_exit();
1626
1627  fallback:
1628 #endif
1629         while ((count = safe_read(f, iobuf, IOBUF_SIZE)) > 0) {
1630                 ssize_t n;
1631                 USE_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1632                 n = full_write(1, iobuf, count);
1633                 if (count != n)
1634                         break;
1635                 USE_FEATURE_HTTPD_RANGES(range_len -= count;)
1636                 if (!range_len)
1637                         break;
1638         }
1639 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1640  fin:
1641 #endif
1642         if (count < 0 && verbose > 1)
1643                 bb_perror_msg("error");
1644         log_and_exit();
1645 }
1646
1647 static int checkPermIP(void)
1648 {
1649         Htaccess_IP *cur;
1650
1651         /* This could stand some work */
1652         for (cur = ip_a_d; cur; cur = cur->next) {
1653 #if DEBUG
1654                 fprintf(stderr,
1655                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1656                         rmt_ip_str,
1657                         (unsigned char)(cur->ip >> 24),
1658                         (unsigned char)(cur->ip >> 16),
1659                         (unsigned char)(cur->ip >> 8),
1660                         (unsigned char)(cur->ip),
1661                         (unsigned char)(cur->mask >> 24),
1662                         (unsigned char)(cur->mask >> 16),
1663                         (unsigned char)(cur->mask >> 8),
1664                         (unsigned char)(cur->mask)
1665                 );
1666 #endif
1667                 if ((rmt_ip & cur->mask) == cur->ip)
1668                         return cur->allow_deny == 'A';   /* Allow/Deny */
1669         }
1670
1671         /* if unconfigured, return 1 - access from all */
1672         return !flg_deny_all;
1673 }
1674
1675 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1676 /*
1677  * Check the permission file for access password protected.
1678  *
1679  * If config file isn't present, everything is allowed.
1680  * Entries are of the form you can see example from header source
1681  *
1682  * path      The file path.
1683  * request   User information to validate.
1684  *
1685  * Returns 1 if request is OK.
1686  */
1687 static int checkPerm(const char *path, const char *request)
1688 {
1689         Htaccess *cur;
1690         const char *p;
1691         const char *p0;
1692
1693         const char *prev = NULL;
1694
1695         /* This could stand some work */
1696         for (cur = g_auth; cur; cur = cur->next) {
1697                 size_t l;
1698
1699                 p0 = cur->before_colon;
1700                 if (prev != NULL && strcmp(prev, p0) != 0)
1701                         continue;       /* find next identical */
1702                 p = cur->after_colon;
1703                 if (DEBUG)
1704                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", p0, request);
1705
1706                 l = strlen(p0);
1707                 if (strncmp(p0, path, l) == 0
1708                  && (l == 1 || path[l] == '/' || path[l] == '\0')
1709                 ) {
1710                         char *u;
1711                         /* path match found.  Check request */
1712                         /* for check next /path:user:password */
1713                         prev = p0;
1714                         u = strchr(request, ':');
1715                         if (u == NULL) {
1716                                 /* bad request, ':' required */
1717                                 break;
1718                         }
1719
1720                         if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1721                                 char *cipher;
1722                                 char *pp;
1723
1724                                 if (strncmp(p, request, u - request) != 0) {
1725                                         /* user doesn't match */
1726                                         continue;
1727                                 }
1728                                 pp = strchr(p, ':');
1729                                 if (pp && pp[1] == '$' && pp[2] == '1'
1730                                  && pp[3] == '$' && pp[4]
1731                                 ) {
1732                                         pp++;
1733                                         cipher = pw_encrypt(u+1, pp);
1734                                         if (strcmp(cipher, pp) == 0)
1735                                                 goto set_remoteuser_var;   /* Ok */
1736                                         /* unauthorized */
1737                                         continue;
1738                                 }
1739                         }
1740
1741                         if (strcmp(p, request) == 0) {
1742  set_remoteuser_var:
1743                                 remoteuser = xstrndup(request, u - request);
1744                                 return 1;   /* Ok */
1745                         }
1746                         /* unauthorized */
1747                 }
1748         } /* for */
1749
1750         return prev == NULL;
1751 }
1752 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1753
1754 #if ENABLE_FEATURE_HTTPD_PROXY
1755 static Htaccess_Proxy *find_proxy_entry(const char *url)
1756 {
1757         Htaccess_Proxy *p;
1758         for (p = proxy; p; p = p->next) {
1759                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1760                         return p;
1761         }
1762         return NULL;
1763 }
1764 #endif
1765
1766 /*
1767  * Handle timeouts
1768  */
1769 static void exit_on_signal(int sig) ATTRIBUTE_NORETURN;
1770 static void exit_on_signal(int sig ATTRIBUTE_UNUSED)
1771 {
1772         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1773 }
1774
1775 /*
1776  * Handle an incoming http request and exit.
1777  */
1778 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) ATTRIBUTE_NORETURN;
1779 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1780 {
1781         static const char request_GET[] ALIGN1 = "GET";
1782         struct stat sb;
1783         char *urlcopy;
1784         char *urlp;
1785         char *tptr;
1786         int ip_allowed;
1787 #if ENABLE_FEATURE_HTTPD_CGI
1788         static const char request_HEAD[] ALIGN1 = "HEAD";
1789         const char *prequest;
1790         char *cookie = NULL;
1791         char *content_type = NULL;
1792         unsigned long length = 0;
1793 #elif ENABLE_FEATURE_HTTPD_PROXY
1794 #define prequest request_GET
1795         unsigned long length = 0;
1796 #endif
1797         char http_major_version;
1798 #if ENABLE_FEATURE_HTTPD_PROXY
1799         char http_minor_version;
1800         char *header_buf = header_buf; /* for gcc */
1801         char *header_ptr = header_ptr;
1802         Htaccess_Proxy *proxy_entry;
1803 #endif
1804 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1805         int credentials = -1;  /* if not required this is Ok */
1806 #endif
1807
1808         /* Allocation of iobuf is postponed until now
1809          * (IOW, server process doesn't need to waste 8k) */
1810         iobuf = xmalloc(IOBUF_SIZE);
1811
1812         rmt_ip = 0;
1813         if (fromAddr->u.sa.sa_family == AF_INET) {
1814                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1815         }
1816 #if ENABLE_FEATURE_IPV6
1817         if (fromAddr->u.sa.sa_family == AF_INET6
1818          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1819          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1820          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1821                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1822 #endif
1823         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1824                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1825         }
1826         if (verbose) {
1827                 /* this trick makes -v logging much simpler */
1828                 applet_name = rmt_ip_str;
1829                 if (verbose > 2)
1830                         bb_error_msg("connected");
1831         }
1832
1833         /* Install timeout handler */
1834         signal_no_SA_RESTART_empty_mask(SIGALRM, exit_on_signal);
1835         alarm(HEADER_READ_TIMEOUT);
1836
1837         if (!get_line()) /* EOF or error or empty line */
1838                 send_headers_and_exit(HTTP_BAD_REQUEST);
1839
1840         /* Determine type of request (GET/POST) */
1841         urlp = strpbrk(iobuf, " \t");
1842         if (urlp == NULL)
1843                 send_headers_and_exit(HTTP_BAD_REQUEST);
1844         *urlp++ = '\0';
1845 #if ENABLE_FEATURE_HTTPD_CGI
1846         prequest = request_GET;
1847         if (strcasecmp(iobuf, prequest) != 0) {
1848                 prequest = request_HEAD;
1849                 if (strcasecmp(iobuf, prequest) != 0) {
1850                         prequest = "POST";
1851                         if (strcasecmp(iobuf, prequest) != 0)
1852                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1853                 }
1854         }
1855 #else
1856         if (strcasecmp(iobuf, request_GET) != 0)
1857                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1858 #endif
1859         urlp = skip_whitespace(urlp);
1860         if (urlp[0] != '/')
1861                 send_headers_and_exit(HTTP_BAD_REQUEST);
1862
1863         /* Find end of URL and parse HTTP version, if any */
1864         http_major_version = '0';
1865         USE_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1866         tptr = strchrnul(urlp, ' ');
1867         /* Is it " HTTP/"? */
1868         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1869                 http_major_version = tptr[6];
1870                 USE_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1871         }
1872         *tptr = '\0';
1873
1874         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1875         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1876         /*if (urlcopy == NULL)
1877          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1878         strcpy(urlcopy, urlp);
1879         /* NB: urlcopy ptr is never changed after this */
1880
1881         /* Extract url args if present */
1882         g_query = NULL;
1883         tptr = strchr(urlcopy, '?');
1884         if (tptr) {
1885                 *tptr++ = '\0';
1886                 g_query = tptr;
1887         }
1888
1889         /* Decode URL escape sequences */
1890         tptr = decodeString(urlcopy, 0);
1891         if (tptr == NULL)
1892                 send_headers_and_exit(HTTP_BAD_REQUEST);
1893         if (tptr == urlcopy + 1) {
1894                 /* '/' or NUL is encoded */
1895                 send_headers_and_exit(HTTP_NOT_FOUND);
1896         }
1897
1898         /* Canonicalize path */
1899         /* Algorithm stolen from libbb bb_simplify_path(),
1900          * but don't strdup, retain trailing slash, protect root */
1901         urlp = tptr = urlcopy;
1902         do {
1903                 if (*urlp == '/') {
1904                         /* skip duplicate (or initial) slash */
1905                         if (*tptr == '/') {
1906                                 continue;
1907                         }
1908                         if (*tptr == '.') {
1909                                 /* skip extra "/./" */
1910                                 if (tptr[1] == '/' || !tptr[1]) {
1911                                         continue;
1912                                 }
1913                                 /* "..": be careful */
1914                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1915                                         ++tptr;
1916                                         if (urlp == urlcopy) /* protect root */
1917                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1918                                         while (*--urlp != '/') /* omit previous dir */;
1919                                                 continue;
1920                                 }
1921                         }
1922                 }
1923                 *++urlp = *tptr;
1924         } while (*++tptr);
1925         *++urlp = '\0';       /* terminate after last character */
1926
1927         /* If URL is a directory, add '/' */
1928         if (urlp[-1] != '/') {
1929                 if (is_directory(urlcopy + 1, 1, &sb)) {
1930                         found_moved_temporarily = urlcopy;
1931                 }
1932         }
1933
1934         /* Log it */
1935         if (verbose > 1)
1936                 bb_error_msg("url:%s", urlcopy);
1937
1938         tptr = urlcopy;
1939         ip_allowed = checkPermIP();
1940         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1941                 /* have path1/path2 */
1942                 *tptr = '\0';
1943                 if (is_directory(urlcopy + 1, 1, &sb)) {
1944                         /* may be having subdir config */
1945                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1946                         ip_allowed = checkPermIP();
1947                 }
1948                 *tptr = '/';
1949         }
1950
1951 #if ENABLE_FEATURE_HTTPD_PROXY
1952         proxy_entry = find_proxy_entry(urlcopy);
1953         if (proxy_entry)
1954                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1955 #endif
1956
1957         if (http_major_version >= '0') {
1958                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1959
1960                 /* Read until blank line for HTTP version specified, else parse immediate */
1961                 while (1) {
1962                         alarm(HEADER_READ_TIMEOUT);
1963                         if (!get_line())
1964                                 break; /* EOF or error or empty line */
1965                         if (DEBUG)
1966                                 bb_error_msg("header: '%s'", iobuf);
1967
1968 #if ENABLE_FEATURE_HTTPD_PROXY
1969                         /* We need 2 more bytes for yet another "\r\n" -
1970                          * see near fdprintf(proxy_fd...) further below */
1971                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1972                                 int len = strlen(iobuf);
1973                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1974                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1975                                 memcpy(header_ptr, iobuf, len);
1976                                 header_ptr += len;
1977                                 header_ptr[0] = '\r';
1978                                 header_ptr[1] = '\n';
1979                                 header_ptr += 2;
1980                         }
1981 #endif
1982
1983 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1984                         /* Try and do our best to parse more lines */
1985                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1986                                 /* extra read only for POST */
1987                                 if (prequest != request_GET
1988 #if ENABLE_FEATURE_HTTPD_CGI
1989                                  && prequest != request_HEAD
1990 #endif
1991                                 ) {
1992                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1993                                         if (!tptr[0])
1994                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1995                                         /* not using strtoul: it ignores leading minus! */
1996                                         length = bb_strtou(tptr, NULL, 10);
1997                                         /* length is "ulong", but we need to pass it to int later */
1998                                         if (errno || length > INT_MAX)
1999                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
2000                                 }
2001                         }
2002 #endif
2003 #if ENABLE_FEATURE_HTTPD_CGI
2004                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
2005                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
2006                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
2007                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
2008                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
2009                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
2010                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2011                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2012                         }
2013 #endif
2014 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2015                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2016                                 /* We only allow Basic credentials.
2017                                  * It shows up as "Authorization: Basic <userid:password>" where
2018                                  * the userid:password is base64 encoded.
2019                                  */
2020                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2021                                 if (STRNCASECMP(tptr, "Basic") != 0)
2022                                         continue;
2023                                 tptr += sizeof("Basic")-1;
2024                                 /* decodeBase64() skips whitespace itself */
2025                                 decodeBase64(tptr);
2026                                 credentials = checkPerm(urlcopy, tptr);
2027                         }
2028 #endif          /* FEATURE_HTTPD_BASIC_AUTH */
2029 #if ENABLE_FEATURE_HTTPD_RANGES
2030                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2031                                 /* We know only bytes=NNN-[MMM] */
2032                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2033                                 if (strncmp(s, "bytes=", 6) == 0) {
2034                                         s += sizeof("bytes=")-1;
2035                                         range_start = BB_STRTOOFF(s, &s, 10);
2036                                         if (s[0] != '-' || range_start < 0) {
2037                                                 range_start = 0;
2038                                         } else if (s[1]) {
2039                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2040                                                 if (errno || range_end < range_start)
2041                                                         range_start = 0;
2042                                         }
2043                                 }
2044                         }
2045 #endif
2046                 } /* while extra header reading */
2047         }
2048
2049         /* We are done reading headers, disable peer timeout */
2050         alarm(0);
2051
2052         if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || ip_allowed == 0) {
2053                 /* protect listing [/path]/httpd_conf or IP deny */
2054                 send_headers_and_exit(HTTP_FORBIDDEN);
2055         }
2056
2057 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2058         if (credentials <= 0 && checkPerm(urlcopy, ":") == 0) {
2059                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2060         }
2061 #endif
2062
2063         if (found_moved_temporarily) {
2064                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2065         }
2066
2067 #if ENABLE_FEATURE_HTTPD_PROXY
2068         if (proxy_entry != NULL) {
2069                 int proxy_fd;
2070                 len_and_sockaddr *lsa;
2071
2072                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2073                 if (proxy_fd < 0)
2074                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2075                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2076                 if (lsa == NULL)
2077                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2078                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2079                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2080                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2081                                 prequest, /* GET or POST */
2082                                 proxy_entry->url_to, /* url part 1 */
2083                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2084                                 (g_query ? "?" : ""), /* "?" (maybe) */
2085                                 (g_query ? g_query : ""), /* query string (maybe) */
2086                                 http_major_version, http_minor_version);
2087                 header_ptr[0] = '\r';
2088                 header_ptr[1] = '\n';
2089                 header_ptr += 2;
2090                 write(proxy_fd, header_buf, header_ptr - header_buf);
2091                 free(header_buf); /* on the order of 8k, free it */
2092                 /* cgi_io_loop_and_exit needs to have two disctinct fds */
2093                 cgi_io_loop_and_exit(proxy_fd, dup(proxy_fd), length);
2094         }
2095 #endif
2096
2097         tptr = urlcopy + 1;      /* skip first '/' */
2098
2099 #if ENABLE_FEATURE_HTTPD_CGI
2100         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2101                 if (tptr[8] == '\0') {
2102                         /* protect listing "cgi-bin/" */
2103                         send_headers_and_exit(HTTP_FORBIDDEN);
2104                 }
2105                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2106         }
2107 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2108         {
2109                 char *suffix = strrchr(tptr, '.');
2110                 if (suffix) {
2111                         Htaccess *cur;
2112                         for (cur = script_i; cur; cur = cur->next) {
2113                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2114                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2115                                 }
2116                         }
2117                 }
2118         }
2119 #endif
2120         if (prequest != request_GET && prequest != request_HEAD) {
2121                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2122         }
2123 #endif  /* FEATURE_HTTPD_CGI */
2124
2125         if (urlp[-1] == '/')
2126                 strcpy(urlp, index_page);
2127         if (stat(tptr, &sb) == 0) {
2128                 file_size = sb.st_size;
2129                 last_mod = sb.st_mtime;
2130         }
2131 #if ENABLE_FEATURE_HTTPD_CGI
2132         else if (urlp[-1] == '/') {
2133                 /* It's a dir URL and there is no index.html
2134                  * Try cgi-bin/index.cgi */
2135                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2136                         urlp[0] = '\0';
2137                         g_query = urlcopy;
2138                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2139                 }
2140         }
2141 #endif
2142         /* else {
2143          *      fall through to send_file, it errors out if open fails
2144          * }
2145          */
2146
2147         send_file_and_exit(tptr,
2148 #if ENABLE_FEATURE_HTTPD_CGI
2149                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2150 #else
2151                 SEND_HEADERS_AND_BODY
2152 #endif
2153         );
2154 }
2155
2156 /*
2157  * The main http server function.
2158  * Given a socket, listen for new connections and farm out
2159  * the processing as a [v]forked process.
2160  * Never returns.
2161  */
2162 #if BB_MMU
2163 static void mini_httpd(int server_socket) ATTRIBUTE_NORETURN;
2164 static void mini_httpd(int server_socket)
2165 {
2166         /* NB: it's best to not use xfuncs in this loop before fork().
2167          * Otherwise server may die on transient errors (temporary
2168          * out-of-memory condition, etc), which is Bad(tm).
2169          * Try to do any dangerous calls after fork.
2170          */
2171         while (1) {
2172                 int n;
2173                 len_and_sockaddr fromAddr;
2174
2175                 /* Wait for connections... */
2176                 fromAddr.len = LSA_SIZEOF_SA;
2177                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2178
2179                 if (n < 0)
2180                         continue;
2181                 /* set the KEEPALIVE option to cull dead connections */
2182                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2183
2184                 if (fork() == 0) {
2185                         /* child */
2186 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2187                         /* Do not reload config on HUP */
2188                         signal(SIGHUP, SIG_IGN);
2189 #endif
2190                         close(server_socket);
2191                         xmove_fd(n, 0);
2192                         xdup2(0, 1);
2193
2194                         handle_incoming_and_exit(&fromAddr);
2195                 }
2196                 /* parent, or fork failed */
2197                 close(n);
2198         } /* while (1) */
2199         /* never reached */
2200 }
2201 #else
2202 static void mini_httpd_nommu(int server_socket, int argc, char **argv) ATTRIBUTE_NORETURN;
2203 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2204 {
2205         char *argv_copy[argc + 2];
2206
2207         argv_copy[0] = argv[0];
2208         argv_copy[1] = (char*)"-i";
2209         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2210
2211         /* NB: it's best to not use xfuncs in this loop before vfork().
2212          * Otherwise server may die on transient errors (temporary
2213          * out-of-memory condition, etc), which is Bad(tm).
2214          * Try to do any dangerous calls after fork.
2215          */
2216         while (1) {
2217                 int n;
2218                 len_and_sockaddr fromAddr;
2219
2220                 /* Wait for connections... */
2221                 fromAddr.len = LSA_SIZEOF_SA;
2222                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2223
2224                 if (n < 0)
2225                         continue;
2226                 /* set the KEEPALIVE option to cull dead connections */
2227                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2228
2229                 if (vfork() == 0) {
2230                         /* child */
2231 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2232                         /* Do not reload config on HUP */
2233                         signal(SIGHUP, SIG_IGN);
2234 #endif
2235                         close(server_socket);
2236                         xmove_fd(n, 0);
2237                         xdup2(0, 1);
2238
2239                         /* Run a copy of ourself in inetd mode */
2240                         re_exec(argv_copy);
2241                 }
2242                 /* parent, or vfork failed */
2243                 close(n);
2244         } /* while (1) */
2245         /* never reached */
2246 }
2247 #endif
2248
2249 /*
2250  * Process a HTTP connection on stdin/out.
2251  * Never returns.
2252  */
2253 static void mini_httpd_inetd(void) ATTRIBUTE_NORETURN;
2254 static void mini_httpd_inetd(void)
2255 {
2256         len_and_sockaddr fromAddr;
2257
2258         fromAddr.len = LSA_SIZEOF_SA;
2259         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2260         handle_incoming_and_exit(&fromAddr);
2261 }
2262
2263 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2264 static void sighup_handler(int sig)
2265 {
2266         parse_conf(default_path_httpd_conf, sig == SIGHUP ? SIGNALED_PARSE : FIRST_PARSE);
2267
2268         signal_SA_RESTART_empty_mask(SIGHUP, sighup_handler);
2269 }
2270 #endif
2271
2272 enum {
2273         c_opt_config_file = 0,
2274         d_opt_decode_url,
2275         h_opt_home_httpd,
2276         USE_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2277         USE_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2278         USE_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2279         USE_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2280         p_opt_port      ,
2281         p_opt_inetd     ,
2282         p_opt_foreground,
2283         p_opt_verbose   ,
2284         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2285         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2286         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2287         OPT_ENCODE_URL  = USE_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2288         OPT_REALM       = USE_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2289         OPT_MD5         = USE_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2290         OPT_SETUID      = USE_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2291         OPT_PORT        = 1 << p_opt_port,
2292         OPT_INETD       = 1 << p_opt_inetd,
2293         OPT_FOREGROUND  = 1 << p_opt_foreground,
2294         OPT_VERBOSE     = 1 << p_opt_verbose,
2295 };
2296
2297
2298 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2299 int httpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
2300 {
2301         int server_socket = server_socket; /* for gcc */
2302         unsigned opt;
2303         char *url_for_decode;
2304         USE_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2305         USE_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2306         USE_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2307         USE_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2308
2309         INIT_G();
2310
2311 #if ENABLE_LOCALE_SUPPORT
2312         /* Undo busybox.c: we want to speak English in http (dates etc) */
2313         setlocale(LC_TIME, "C");
2314 #endif
2315
2316         home_httpd = xrealloc_getcwd_or_warn(NULL);
2317         /* -v counts, -i implies -f */
2318         opt_complementary = "vv:if";
2319         /* We do not "absolutize" path given by -h (home) opt.
2320          * If user gives relative path in -h,
2321          * $SCRIPT_FILENAME will not be set. */
2322         opt = getopt32(argv, "c:d:h:"
2323                         USE_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2324                         USE_FEATURE_HTTPD_BASIC_AUTH("r:")
2325                         USE_FEATURE_HTTPD_AUTH_MD5("m:")
2326                         USE_FEATURE_HTTPD_SETUID("u:")
2327                         "p:ifv",
2328                         &configFile, &url_for_decode, &home_httpd
2329                         USE_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2330                         USE_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2331                         USE_FEATURE_HTTPD_AUTH_MD5(, &pass)
2332                         USE_FEATURE_HTTPD_SETUID(, &s_ugid)
2333                         , &bind_addr_or_port
2334                         , &verbose
2335                 );
2336         if (opt & OPT_DECODE_URL) {
2337                 fputs(decodeString(url_for_decode, 1), stdout);
2338                 return 0;
2339         }
2340 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2341         if (opt & OPT_ENCODE_URL) {
2342                 fputs(encodeString(url_for_encode), stdout);
2343                 return 0;
2344         }
2345 #endif
2346 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2347         if (opt & OPT_MD5) {
2348                 puts(pw_encrypt(pass, "$1$"));
2349                 return 0;
2350         }
2351 #endif
2352 #if ENABLE_FEATURE_HTTPD_SETUID
2353         if (opt & OPT_SETUID) {
2354                 if (!get_uidgid(&ugid, s_ugid, 1))
2355                         bb_error_msg_and_die("unknown user[:group] "
2356                                                 "name '%s'", s_ugid);
2357         }
2358 #endif
2359
2360 #if !BB_MMU
2361         if (!(opt & OPT_FOREGROUND)) {
2362                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2363         }
2364 #endif
2365
2366         xchdir(home_httpd);
2367         if (!(opt & OPT_INETD)) {
2368                 signal(SIGCHLD, SIG_IGN);
2369                 server_socket = openServer();
2370 #if ENABLE_FEATURE_HTTPD_SETUID
2371                 /* drop privileges */
2372                 if (opt & OPT_SETUID) {
2373                         if (ugid.gid != (gid_t)-1) {
2374                                 if (setgroups(1, &ugid.gid) == -1)
2375                                         bb_perror_msg_and_die("setgroups");
2376                                 xsetgid(ugid.gid);
2377                         }
2378                         xsetuid(ugid.uid);
2379                 }
2380 #endif
2381         }
2382
2383 #if 0 /*was #if ENABLE_FEATURE_HTTPD_CGI*/
2384         /* User can do it himself: 'env - PATH="$PATH" httpd'
2385          * We don't do it because we don't want to screw users
2386          * which want to do
2387          * 'env - VAR1=val1 VAR2=val2 httpd'
2388          * and have VAR1 and VAR2 values visible in their CGIs.
2389          * Besides, it is also smaller. */
2390         {
2391                 char *p = getenv("PATH");
2392                 /* env strings themself are not freed, no need to xstrdup(p): */
2393                 clearenv();
2394                 if (p)
2395                         putenv(p - 5);
2396 //              if (!(opt & OPT_INETD))
2397 //                      setenv_long("SERVER_PORT", ???);
2398         }
2399 #endif
2400
2401 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2402         if (!(opt & OPT_INETD))
2403                 sighup_handler(0);
2404 #endif
2405         parse_conf(default_path_httpd_conf, FIRST_PARSE);
2406
2407         xfunc_error_retval = 0;
2408         if (opt & OPT_INETD)
2409                 mini_httpd_inetd();
2410 #if BB_MMU
2411         if (!(opt & OPT_FOREGROUND))
2412                 bb_daemonize(0); /* don't change current directory */
2413         mini_httpd(server_socket); /* never returns */
2414 #else
2415         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2416 #endif
2417         /* return 0; */
2418 }