networking/httpd.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * httpd implementation for busybox
   4  *
   5  * Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
   6  * Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
   7  *
   8  * simplify patch stolen from libbb without using strdup
   9  *
  10  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  11  *
  12  *****************************************************************************
  13  *
  14  * Typical usage:
  15  *   for non root user
  16  * httpd -p 8080 -h $HOME/public_html
  17  *   or for daemon start from rc script with uid=0:
  18  * httpd -u www
  19  * This is equivalent if www user have uid=80 to
  20  * httpd -p 80 -u 80 -h /www -c /etc/httpd.conf -r "Web Server Authentication"
  21  *
  22  *
  23  * When a url starts by "/cgi-bin/" it is assumed to be a cgi script.  The
  24  * server changes directory to the location of the script and executes it
  25  * after setting QUERY_STRING and other environment variables.
  26  *
  27  * Doc:
  28  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
  29  *
  30  * The applet can also be invoked as a url arg decoder and html text encoder
  31  * as follows:
  32  *  foo=`httpd -d $foo`           # decode "Hello%20World" as "Hello World"
  33  *  bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
  34  * Note that url encoding for arguments is not the same as html encoding for
  35  * presentation.  -d decodes a url-encoded argument while -e encodes in html
  36  * for page display.
  37  *
  38  * httpd.conf has the following format:
  39  *
  40  * 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 - only first char matters.
  59  * Deny/Allow IP logic:
  60  *  - Default is to allow all (Allow all (A:*) is a no-op).
  61  *  - Deny rules take precedence over allow rules.
  62  *  - "Deny all" rule (D:*) is applied last.
  63  *
  64  * Example:
  65  *   1. Allow only specified addresses
  66  *     A:172.20          # Allow any address that begins with 172.20.
  67  *     A:10.10.          # Allow any address that begins with 10.10.
  68  *     A:127.0.0.1       # Allow local loopback connections
  69  *     D:*               # Deny from other IP connections
  70  *
  71  *   2. Only deny specified addresses
  72  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
  73  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
  74  *     A:*             # (optional line added for clarity)
  75  *
  76  * If a sub directory contains a config file it is parsed and merged with
  77  * any existing settings as if it was appended to the original configuration.
  78  *
  79  * subdir paths are relative to the containing subdir and thus cannot
  80  * affect the parent rules.
  81  *
  82  * Note that since the sub dir is parsed in the forked thread servicing the
  83  * subdir http request, any merge is discarded when the process exits.  As a
  84  * result, the subdir settings only have a lifetime of a single request.
  85  *
  86  * Custom error pages can contain an absolute path or be relative to
  87  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
  88  * page can only be defined in the root configuration file and are not taken
  89  * into account in local (directories) config files.
  90  *
  91  * If -c is not set, an attempt will be made to open the default
  92  * root configuration file.  If -c is set and the file is not found, the
  93  * server exits with an error.
  94  *
  95  */
  96
  97 #include "libbb.h"
  98 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
  99 #include <sys/sendfile.h>
 100 #endif
 101
 102 //#define DEBUG 1
 103 #define DEBUG 0
 104
 105 #define IOBUF_SIZE 8192    /* IO buffer */
 106
 107 /* amount of buffering in a pipe */
 108 #ifndef PIPE_BUF
 109 # define PIPE_BUF 4096
 110 #endif
 111 #if PIPE_BUF >= IOBUF_SIZE
 112 # error "PIPE_BUF >= IOBUF_SIZE"
 113 #endif
 114
 115 #define HEADER_READ_TIMEOUT 60
 116
 117 static const char default_path_httpd_conf[] ALIGN1 = "/etc";
 118 static const char httpd_conf[] ALIGN1 = "httpd.conf";
 119 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
 120
 121 typedef struct has_next_ptr {
 122         struct has_next_ptr *next;
 123 } has_next_ptr;
 124
 125 /* Must have "next" as a first member */
 126 typedef struct Htaccess {
 127         struct Htaccess *next;
 128         char *after_colon;
 129         char before_colon[1];  /* really bigger, must be last */
 130 } Htaccess;
 131
 132 /* Must have "next" as a first member */
 133 typedef struct Htaccess_IP {
 134         struct Htaccess_IP *next;
 135         unsigned ip;
 136         unsigned mask;
 137         int allow_deny;
 138 } Htaccess_IP;
 139
 140 /* Must have "next" as a first member */
 141 typedef struct Htaccess_Proxy {
 142         struct Htaccess_Proxy *next;
 143         char *url_from;
 144         char *host_port;
 145         char *url_to;
 146 } Htaccess_Proxy;
 147
 148 enum {
 149         HTTP_OK = 200,
 150         HTTP_PARTIAL_CONTENT = 206,
 151         HTTP_MOVED_TEMPORARILY = 302,
 152         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
 153         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
 154         HTTP_NOT_FOUND = 404,
 155         HTTP_FORBIDDEN = 403,
 156         HTTP_REQUEST_TIMEOUT = 408,
 157         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
 158         HTTP_INTERNAL_SERVER_ERROR = 500,
 159         HTTP_CONTINUE = 100,
 160 #if 0   /* future use */
 161         HTTP_SWITCHING_PROTOCOLS = 101,
 162         HTTP_CREATED = 201,
 163         HTTP_ACCEPTED = 202,
 164         HTTP_NON_AUTHORITATIVE_INFO = 203,
 165         HTTP_NO_CONTENT = 204,
 166         HTTP_MULTIPLE_CHOICES = 300,
 167         HTTP_MOVED_PERMANENTLY = 301,
 168         HTTP_NOT_MODIFIED = 304,
 169         HTTP_PAYMENT_REQUIRED = 402,
 170         HTTP_BAD_GATEWAY = 502,
 171         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
 172         HTTP_RESPONSE_SETSIZE = 0xffffffff
 173 #endif
 174 };
 175
 176 static const uint16_t http_response_type[] ALIGN2 = {
 177         HTTP_OK,
 178 #if ENABLE_FEATURE_HTTPD_RANGES
 179         HTTP_PARTIAL_CONTENT,
 180 #endif
 181         HTTP_MOVED_TEMPORARILY,
 182         HTTP_REQUEST_TIMEOUT,
 183         HTTP_NOT_IMPLEMENTED,
 184 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 185         HTTP_UNAUTHORIZED,
 186 #endif
 187         HTTP_NOT_FOUND,
 188         HTTP_BAD_REQUEST,
 189         HTTP_FORBIDDEN,
 190         HTTP_INTERNAL_SERVER_ERROR,
 191 #if 0   /* not implemented */
 192         HTTP_CREATED,
 193         HTTP_ACCEPTED,
 194         HTTP_NO_CONTENT,
 195         HTTP_MULTIPLE_CHOICES,
 196         HTTP_MOVED_PERMANENTLY,
 197         HTTP_NOT_MODIFIED,
 198         HTTP_BAD_GATEWAY,
 199         HTTP_SERVICE_UNAVAILABLE,
 200 #endif
 201 };
 202
 203 static const struct {
 204         const char *name;
 205         const char *info;
 206 } http_response[ARRAY_SIZE(http_response_type)] = {
 207         { "OK", NULL },
 208 #if ENABLE_FEATURE_HTTPD_RANGES
 209         { "Partial Content", NULL },
 210 #endif
 211         { "Found", NULL },
 212         { "Request Timeout", "No request appeared within 60 seconds" },
 213         { "Not Implemented", "The requested method is not recognized" },
 214 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 215         { "Unauthorized", "" },
 216 #endif
 217         { "Not Found", "The requested URL was not found" },
 218         { "Bad Request", "Unsupported method" },
 219         { "Forbidden", ""  },
 220         { "Internal Server Error", "Internal Server Error" },
 221 #if 0   /* not implemented */
 222         { "Created" },
 223         { "Accepted" },
 224         { "No Content" },
 225         { "Multiple Choices" },
 226         { "Moved Permanently" },
 227         { "Not Modified" },
 228         { "Bad Gateway", "" },
 229         { "Service Unavailable", "" },
 230 #endif
 231 };
 232
 233
 234 struct globals {
 235         int verbose;            /* must be int (used by getopt32) */
 236         smallint flg_deny_all;
 237
 238         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
 239         time_t last_mod;
 240         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
 241         const char *bind_addr_or_port;
 242
 243         const char *g_query;
 244         const char *configFile;
 245         const char *home_httpd;
 246         const char *index_page;
 247
 248         const char *found_mime_type;
 249         const char *found_moved_temporarily;
 250         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
 251
 252         USE_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
 253         USE_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
 254         USE_FEATURE_HTTPD_CGI(char *referer;)
 255         USE_FEATURE_HTTPD_CGI(char *user_agent;)
 256
 257         off_t file_size;        /* -1 - unknown */
 258 #if ENABLE_FEATURE_HTTPD_RANGES
 259         off_t range_start;
 260         off_t range_end;
 261         off_t range_len;
 262 #endif
 263
 264 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 265         Htaccess *g_auth;       /* config user:password lines */
 266 #endif
 267 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 268         Htaccess *mime_a;       /* config mime types */
 269 #endif
 270 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 271         Htaccess *script_i;     /* config script interpreters */
 272 #endif
 273         char *iobuf;            /* [IOBUF_SIZE] */
 274 #define hdr_buf bb_common_bufsiz1
 275         char *hdr_ptr;
 276         int hdr_cnt;
 277 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 278         const char *http_error_page[ARRAY_SIZE(http_response_type)];
 279 #endif
 280 #if ENABLE_FEATURE_HTTPD_PROXY
 281         Htaccess_Proxy *proxy;
 282 #endif
 283 };
 284 #define G (*ptr_to_globals)
 285 #define verbose           (G.verbose          )
 286 #define flg_deny_all      (G.flg_deny_all     )
 287 #define rmt_ip            (G.rmt_ip           )
 288 #define bind_addr_or_port (G.bind_addr_or_port)
 289 #define g_query           (G.g_query          )
 290 #define configFile        (G.configFile       )
 291 #define home_httpd        (G.home_httpd       )
 292 #define index_page        (G.index_page       )
 293 #define found_mime_type   (G.found_mime_type  )
 294 #define found_moved_temporarily (G.found_moved_temporarily)
 295 #define last_mod          (G.last_mod         )
 296 #define ip_a_d            (G.ip_a_d           )
 297 #define g_realm           (G.g_realm          )
 298 #define remoteuser        (G.remoteuser       )
 299 #define referer           (G.referer          )
 300 #define user_agent        (G.user_agent       )
 301 #define file_size         (G.file_size        )
 302 #if ENABLE_FEATURE_HTTPD_RANGES
 303 #define range_start       (G.range_start      )
 304 #define range_end         (G.range_end        )
 305 #define range_len         (G.range_len        )
 306 #endif
 307 #define rmt_ip_str        (G.rmt_ip_str       )
 308 #define g_auth            (G.g_auth           )
 309 #define mime_a            (G.mime_a           )
 310 #define script_i          (G.script_i         )
 311 #define iobuf             (G.iobuf            )
 312 #define hdr_ptr           (G.hdr_ptr          )
 313 #define hdr_cnt           (G.hdr_cnt          )
 314 #define http_error_page   (G.http_error_page  )
 315 #define proxy             (G.proxy            )
 316 #define INIT_G() do { \
 317         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 318         USE_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
 319         bind_addr_or_port = "80"; \
 320         index_page = "index.html"; \
 321         file_size = -1; \
 322 } while (0)
 323
 324 #if !ENABLE_FEATURE_HTTPD_RANGES
 325 enum {
 326         range_start = 0,
 327         range_end = MAXINT(off_t) - 1,
 328         range_len = MAXINT(off_t),
 329 };
 330 #endif
 331
 332
 333 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
 334
 335 /* Prototypes */
 336 enum {
 337         SEND_HEADERS     = (1 << 0),
 338         SEND_BODY        = (1 << 1),
 339         SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
 340 };
 341 static void send_file_and_exit(const char *url, int what) NORETURN;
 342
 343 static void free_llist(has_next_ptr **pptr)
 344 {
 345         has_next_ptr *cur = *pptr;
 346         while (cur) {
 347                 has_next_ptr *t = cur;
 348                 cur = cur->next;
 349                 free(t);
 350         }
 351         *pptr = NULL;
 352 }
 353
 354 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 355  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 356  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 357 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
 358 {
 359         free_llist((has_next_ptr**)pptr);
 360 }
 361 #endif
 362
 363 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
 364 {
 365         free_llist((has_next_ptr**)pptr);
 366 }
 367
 368 /* Returns presumed mask width in bits or < 0 on error.
 369  * Updates strp, stores IP at provided pointer */
 370 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
 371 {
 372         const char *p = *strp;
 373         int auto_mask = 8;
 374         unsigned ip = 0;
 375         int j;
 376
 377         if (*p == '/')
 378                 return -auto_mask;
 379
 380         for (j = 0; j < 4; j++) {
 381                 unsigned octet;
 382
 383                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
 384                         return -auto_mask;
 385                 octet = 0;
 386                 while (*p >= '0' && *p <= '9') {
 387                         octet *= 10;
 388                         octet += *p - '0';
 389                         if (octet > 255)
 390                                 return -auto_mask;
 391                         p++;
 392                 }
 393                 if (*p == '.')
 394                         p++;
 395                 if (*p != '/' && *p)
 396                         auto_mask += 8;
 397                 ip = (ip << 8) | octet;
 398         }
 399         if (*p) {
 400                 if (*p != endc)
 401                         return -auto_mask;
 402                 p++;
 403                 if (*p == '\0')
 404                         return -auto_mask;
 405         }
 406         *ipp = ip;
 407         *strp = p;
 408         return auto_mask;
 409 }
 410
 411 /* Returns 0 on success. Stores IP and mask at provided pointers */
 412 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
 413 {
 414         int i;
 415         unsigned mask;
 416         char *p;
 417
 418         i = scan_ip(&str, ipp, '/');
 419         if (i < 0)
 420                 return i;
 421
 422         if (*str) {
 423                 /* there is /xxx after dotted-IP address */
 424                 i = bb_strtou(str, &p, 10);
 425                 if (*p == '.') {
 426                         /* 'xxx' itself is dotted-IP mask, parse it */
 427                         /* (return 0 (success) only if it has N.N.N.N form) */
 428                         return scan_ip(&str, maskp, '\0') - 32;
 429                 }
 430                 if (*p)
 431                         return -1;
 432         }
 433
 434         if (i > 32)
 435                 return -1;
 436
 437         if (sizeof(unsigned) == 4 && i == 32) {
 438                 /* mask >>= 32 below may not work */
 439                 mask = 0;
 440         } else {
 441                 mask = 0xffffffff;
 442                 mask >>= i;
 443         }
 444         /* i == 0 -> *maskp = 0x00000000
 445          * i == 1 -> *maskp = 0x80000000
 446          * i == 4 -> *maskp = 0xf0000000
 447          * i == 31 -> *maskp = 0xfffffffe
 448          * i == 32 -> *maskp = 0xffffffff */
 449         *maskp = (uint32_t)(~mask);
 450         return 0;
 451 }
 452
 453 /*
 454  * Parse configuration file into in-memory linked list.
 455  *
 456  * The first non-white character is examined to determine if the config line
 457  * is one of the following:
 458  *    .ext:mime/type   # new mime type not compiled into httpd
 459  *    [adAD]:from      # ip address allow/deny, * for wildcard
 460  *    /path:user:pass  # username/password
 461  *    Ennn:error.html  # error page for status nnn
 462  *    P:/url:[http://]hostname[:port]/new/path # reverse proxy
 463  *
 464  * Any previous IP rules are discarded.
 465  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
 466  * are also discarded.  That is, previous settings are retained if flag is
 467  * SUBDIR_PARSE.
 468  * Error pages are only parsed on the main config file.
 469  *
 470  * path   Path where to look for httpd.conf (without filename).
 471  * flag   Type of the parse request.
 472  */
 473 /* flag */
 474 #define FIRST_PARSE          0
 475 #define SUBDIR_PARSE         1
 476 #define SIGNALED_PARSE       2
 477 #define FIND_FROM_HTTPD_ROOT 3
 478 static void parse_conf(const char *path, int flag)
 479 {
 480         FILE *f;
 481 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 482         Htaccess *prev;
 483 #endif
 484 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 485  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 486  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 487         Htaccess *cur;
 488 #endif
 489         const char *filename = configFile;
 490         char buf[160];
 491         char *p, *p0;
 492         char *after_colon;
 493         Htaccess_IP *pip;
 494
 495         /* discard old rules */
 496         free_Htaccess_IP_list(&ip_a_d);
 497         flg_deny_all = 0;
 498 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 499  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 500  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 501         /* retain previous auth and mime config only for subdir parse */
 502         if (flag != SUBDIR_PARSE) {
 503 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 504                 free_Htaccess_list(&g_auth);
 505 #endif
 506 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 507                 free_Htaccess_list(&mime_a);
 508 #endif
 509 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 510                 free_Htaccess_list(&script_i);
 511 #endif
 512         }
 513 #endif
 514
 515         if (flag == SUBDIR_PARSE || filename == NULL) {
 516                 filename = alloca(strlen(path) + sizeof(httpd_conf) + 2);
 517                 sprintf((char *)filename, "%s/%s", path, httpd_conf);
 518         }
 519
 520         while ((f = fopen(filename, "r")) == NULL) {
 521                 if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) {
 522                         /* config file not found, no changes to config */
 523                         return;
 524                 }
 525                 if (configFile && flag == FIRST_PARSE) /* if -c option given */
 526                         bb_simple_perror_msg_and_die(filename);
 527                 flag = FIND_FROM_HTTPD_ROOT;
 528                 filename = httpd_conf;
 529         }
 530
 531 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 532         prev = g_auth;
 533 #endif
 534         /* This could stand some work */
 535         while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) {
 536                 after_colon = NULL;
 537                 for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) {
 538                         if (!isspace(*p0)) {
 539                                 *p++ = *p0;
 540                                 if (*p0 == ':' && after_colon == NULL)
 541                                         after_colon = p;
 542                         }
 543                 }
 544                 *p = '\0';
 545
 546                 /* test for empty or strange line */
 547                 if (after_colon == NULL || *after_colon == '\0')
 548                         continue;
 549                 p0 = buf;
 550                 if (*p0 == 'd' || *p0 == 'a')
 551                         *p0 -= 0x20; /* a/d -> A/D */
 552                 if (*after_colon == '*') {
 553                         if (*p0 == 'D') {
 554                                 /* memorize "deny all" */
 555                                 flg_deny_all = 1;
 556                         }
 557                         /* skip assumed "A:*", it is a default anyway */
 558                         continue;
 559                 }
 560
 561                 if (*p0 == 'A' || *p0 == 'D') {
 562                         /* storing current config IP line */
 563                         pip = xzalloc(sizeof(Htaccess_IP));
 564                         if (scan_ip_mask(after_colon, &(pip->ip), &(pip->mask))) {
 565                                 /* IP{/mask} syntax error detected, protect all */
 566                                 *p0 = 'D';
 567                                 pip->mask = 0;
 568                         }
 569                         pip->allow_deny = *p0;
 570                         if (*p0 == 'D') {
 571                                 /* Deny:from_IP - prepend */
 572                                 pip->next = ip_a_d;
 573                                 ip_a_d = pip;
 574                         } else {
 575                                 /* A:from_IP - append (thus D precedes A) */
 576                                 Htaccess_IP *prev_IP = ip_a_d;
 577                                 if (prev_IP == NULL) {
 578                                         ip_a_d = pip;
 579                                 } else {
 580                                         while (prev_IP->next)
 581                                                 prev_IP = prev_IP->next;
 582                                         prev_IP->next = pip;
 583                                 }
 584                         }
 585                         continue;
 586                 }
 587
 588 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 589                 if (flag == FIRST_PARSE && *p0 == 'E') {
 590                         unsigned i;
 591                         int status = atoi(++p0); /* error status code */
 592                         if (status < HTTP_CONTINUE) {
 593                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 594                                 continue;
 595                         }
 596                         /* then error page; find matching status */
 597                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 598                                 if (http_response_type[i] == status) {
 599                                         /* We chdir to home_httpd, thus no need to
 600                                          * concat_path_file(home_httpd, after_colon)
 601                                          * here */
 602                                         http_error_page[i] = xstrdup(after_colon);
 603                                         break;
 604                                 }
 605                         }
 606                         continue;
 607                 }
 608 #endif
 609
 610 #if ENABLE_FEATURE_HTTPD_PROXY
 611                 if (flag == FIRST_PARSE && *p0 == 'P') {
 612                         /* P:/url:[http://]hostname[:port]/new/path */
 613                         char *url_from, *host_port, *url_to;
 614                         Htaccess_Proxy *proxy_entry;
 615
 616                         url_from = after_colon;
 617                         host_port = strchr(after_colon, ':');
 618                         if (host_port == NULL) {
 619                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 620                                 continue;
 621                         }
 622                         *host_port++ = '\0';
 623                         if (strncmp(host_port, "http://", 7) == 0)
 624                                 host_port += 7;
 625                         if (*host_port == '\0') {
 626                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 627                                 continue;
 628                         }
 629                         url_to = strchr(host_port, '/');
 630                         if (url_to == NULL) {
 631                                 bb_error_msg("config error '%s' in '%s'", buf, filename);
 632                                 continue;
 633                         }
 634                         *url_to = '\0';
 635                         proxy_entry = xzalloc(sizeof(Htaccess_Proxy));
 636                         proxy_entry->url_from = xstrdup(url_from);
 637                         proxy_entry->host_port = xstrdup(host_port);
 638                         *url_to = '/';
 639                         proxy_entry->url_to = xstrdup(url_to);
 640                         proxy_entry->next = proxy;
 641                         proxy = proxy_entry;
 642                         continue;
 643                 }
 644 #endif
 645
 646 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 647                 if (*p0 == '/') {
 648                         /* make full path from httpd root / current_path / config_line_path */
 649                         const char *tp = (flag == SUBDIR_PARSE ? path : "");
 650                         p0 = xmalloc(strlen(tp) + (after_colon - buf) + 2 + strlen(after_colon));
 651                         after_colon[-1] = '\0';
 652                         sprintf(p0, "/%s%s", tp, buf);
 653
 654                         /* looks like bb_simplify_path... */
 655                         tp = p = p0;
 656                         do {
 657                                 if (*p == '/') {
 658                                         if (*tp == '/') {    /* skip duplicate (or initial) slash */
 659                                                 continue;
 660                                         }
 661                                         if (*tp == '.') {
 662                                                 if (tp[1] == '/' || tp[1] == '\0') { /* remove extra '.' */
 663                                                         continue;
 664                                                 }
 665                                                 if ((tp[1] == '.') && (tp[2] == '/' || tp[2] == '\0')) {
 666                                                         ++tp;
 667                                                         if (p > p0) {
 668                                                                 while (*--p != '/') /* omit previous dir */
 669                                                                         continue;
 670                                                         }
 671                                                         continue;
 672                                                 }
 673                                         }
 674                                 }
 675                                 *++p = *tp;
 676                         } while (*++tp);
 677
 678                         if ((p == p0) || (*p != '/')) { /* not a trailing slash */
 679                                 ++p;                    /* so keep last character */
 680                         }
 681                         *p = ':';
 682                         strcpy(p + 1, after_colon);
 683                 }
 684 #endif
 685                 if (*p0 == 'I') {
 686                         index_page = xstrdup(after_colon);
 687                         continue;
 688                 }
 689
 690 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
 691  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
 692  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 693                 /* storing current config line */
 694                 cur = xzalloc(sizeof(Htaccess) + strlen(p0));
 695                 strcpy(cur->before_colon, p0);
 696 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 697                 if (*p0 == '/') /* was malloced - see above */
 698                         free(p0);
 699 #endif
 700                 cur->after_colon = strchr(cur->before_colon, ':');
 701                 *cur->after_colon++ = '\0';
 702 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
 703                 if (cur->before_colon[0] == '.') {
 704                         /* .mime line: prepend to mime_a list */
 705                         cur->next = mime_a;
 706                         mime_a = cur;
 707                         continue;
 708                 }
 709 #endif
 710 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
 711                 if (cur->before_colon[0] == '*' && cur->before_colon[1] == '.') {
 712                         /* script interpreter line: prepend to script_i list */
 713                         cur->next = script_i;
 714                         script_i = cur;
 715                         continue;
 716                 }
 717 #endif
 718 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 719 //TODO: we do not test for leading "/"??
 720 //also, do we leak cur if BASIC_AUTH is off?
 721                 if (prev == NULL) {
 722                         /* first line */
 723                         g_auth = prev = cur;
 724                 } else {
 725                         /* sort path, if current length eq or bigger then move up */
 726                         Htaccess *prev_hti = g_auth;
 727                         size_t l = strlen(cur->before_colon);
 728                         Htaccess *hti;
 729
 730                         for (hti = prev_hti; hti; hti = hti->next) {
 731                                 if (l >= strlen(hti->before_colon)) {
 732                                         /* insert before hti */
 733                                         cur->next = hti;
 734                                         if (prev_hti != hti) {
 735                                                 prev_hti->next = cur;
 736                                         } else {
 737                                                 /* insert as top */
 738                                                 g_auth = cur;
 739                                         }
 740                                         break;
 741                                 }
 742                                 if (prev_hti != hti)
 743                                         prev_hti = prev_hti->next;
 744                         }
 745                         if (!hti) {       /* not inserted, add to bottom */
 746                                 prev->next = cur;
 747                                 prev = cur;
 748                         }
 749                 }
 750 #endif /* BASIC_AUTH */
 751 #endif /* BASIC_AUTH || MIME_TYPES || SCRIPT_INTERPR */
 752          } /* while (fgets) */
 753          fclose(f);
 754 }
 755
 756 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
 757 /*
 758  * Given a string, html-encode special characters.
 759  * This is used for the -e command line option to provide an easy way
 760  * for scripts to encode result data without confusing browsers.  The
 761  * returned string pointer is memory allocated by malloc().
 762  *
 763  * Returns a pointer to the encoded string (malloced).
 764  */
 765 static char *encodeString(const char *string)
 766 {
 767         /* take the simple route and encode everything */
 768         /* could possibly scan once to get length.     */
 769         int len = strlen(string);
 770         char *out = xmalloc(len * 6 + 1);
 771         char *p = out;
 772         char ch;
 773
 774         while ((ch = *string++)) {
 775                 /* very simple check for what to encode */
 776                 if (isalnum(ch))
 777                         *p++ = ch;
 778                 else
 779                         p += sprintf(p, "&#%d;", (unsigned char) ch);
 780         }
 781         *p = '\0';
 782         return out;
 783 }
 784 #endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
 785
 786 /*
 787  * Given a URL encoded string, convert it to plain ascii.
 788  * Since decoding always makes strings smaller, the decode is done in-place.
 789  * Thus, callers should xstrdup() the argument if they do not want the
 790  * argument modified.  The return is the original pointer, allowing this
 791  * function to be easily used as arguments to other functions.
 792  *
 793  * string    The first string to decode.
 794  * option_d  1 if called for httpd -d
 795  *
 796  * Returns a pointer to the decoded string (same as input).
 797  */
 798 static unsigned hex_to_bin(unsigned char c)
 799 {
 800         unsigned v;
 801
 802         v = c - '0';
 803         if (v <= 9)
 804                 return v;
 805         /* c | 0x20: letters to lower case, non-letters
 806          * to (potentially different) non-letters */
 807         v = (unsigned)(c | 0x20) - 'a';
 808         if (v <= 5)
 809                 return v + 10;
 810         return ~0;
 811 }
 812 /* For testing:
 813 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
 814 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
 815 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
 816 */
 817 static char *decodeString(char *orig, int option_d)
 818 {
 819         /* note that decoded string is always shorter than original */
 820         char *string = orig;
 821         char *ptr = string;
 822         char c;
 823
 824         while ((c = *ptr++) != '\0') {
 825                 unsigned v;
 826
 827                 if (option_d && c == '+') {
 828                         *string++ = ' ';
 829                         continue;
 830                 }
 831                 if (c != '%') {
 832                         *string++ = c;
 833                         continue;
 834                 }
 835                 v = hex_to_bin(ptr[0]);
 836                 if (v > 15) {
 837  bad_hex:
 838                         if (!option_d)
 839                                 return NULL;
 840                         *string++ = '%';
 841                         continue;
 842                 }
 843                 v = (v * 16) | hex_to_bin(ptr[1]);
 844                 if (v > 255)
 845                         goto bad_hex;
 846                 if (!option_d && (v == '/' || v == '\0')) {
 847                         /* caller takes it as indication of invalid
 848                          * (dangerous wrt exploits) chars */
 849                         return orig + 1;
 850                 }
 851                 *string++ = v;
 852                 ptr += 2;
 853         }
 854         *string = '\0';
 855         return orig;
 856 }
 857
 858 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 859 /*
 860  * Decode a base64 data stream as per rfc1521.
 861  * Note that the rfc states that non base64 chars are to be ignored.
 862  * Since the decode always results in a shorter size than the input,
 863  * it is OK to pass the input arg as an output arg.
 864  * Parameter: a pointer to a base64 encoded string.
 865  * Decoded data is stored in-place.
 866  */
 867 static void decodeBase64(char *Data)
 868 {
 869         const unsigned char *in = (const unsigned char *)Data;
 870         /* The decoded size will be at most 3/4 the size of the encoded */
 871         unsigned ch = 0;
 872         int i = 0;
 873
 874         while (*in) {
 875                 int t = *in++;
 876
 877                 if (t >= '0' && t <= '9')
 878                         t = t - '0' + 52;
 879                 else if (t >= 'A' && t <= 'Z')
 880                         t = t - 'A';
 881                 else if (t >= 'a' && t <= 'z')
 882                         t = t - 'a' + 26;
 883                 else if (t == '+')
 884                         t = 62;
 885                 else if (t == '/')
 886                         t = 63;
 887                 else if (t == '=')
 888                         t = 0;
 889                 else
 890                         continue;
 891
 892                 ch = (ch << 6) | t;
 893                 i++;
 894                 if (i == 4) {
 895                         *Data++ = (char) (ch >> 16);
 896                         *Data++ = (char) (ch >> 8);
 897                         *Data++ = (char) ch;
 898                         i = 0;
 899                 }
 900         }
 901         *Data = '\0';
 902 }
 903 #endif
 904
 905 /*
 906  * Create a listen server socket on the designated port.
 907  */
 908 static int openServer(void)
 909 {
 910         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
 911         if (!errno && n && n <= 0xffff)
 912                 n = create_and_bind_stream_or_die(NULL, n);
 913         else
 914                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
 915         xlisten(n, 9);
 916         return n;
 917 }
 918
 919 /*
 920  * Log the connection closure and exit.
 921  */
 922 static void log_and_exit(void) NORETURN;
 923 static void log_and_exit(void)
 924 {
 925         /* Paranoia. IE said to be buggy. It may send some extra data
 926          * or be confused by us just exiting without SHUT_WR. Oh well. */
 927         shutdown(1, SHUT_WR);
 928         /* Why??
 929         (this also messes up stdin when user runs httpd -i from terminal)
 930         ndelay_on(0);
 931         while (read(STDIN_FILENO, iobuf, IOBUF_SIZE) > 0)
 932                 continue;
 933         */
 934
 935         if (verbose > 2)
 936                 bb_error_msg("closed");
 937         _exit(xfunc_error_retval);
 938 }
 939
 940 /*
 941  * Create and send HTTP response headers.
 942  * The arguments are combined and sent as one write operation.  Note that
 943  * IE will puke big-time if the headers are not sent in one packet and the
 944  * second packet is delayed for any reason.
 945  * responseNum - the result code to send.
 946  */
 947 static void send_headers(int responseNum)
 948 {
 949         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
 950
 951         const char *responseString = "";
 952         const char *infoString = NULL;
 953         const char *mime_type;
 954 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 955         const char *error_page = NULL;
 956 #endif
 957         unsigned i;
 958         time_t timer = time(0);
 959         char tmp_str[80];
 960         int len;
 961
 962         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
 963                 if (http_response_type[i] == responseNum) {
 964                         responseString = http_response[i].name;
 965                         infoString = http_response[i].info;
 966 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
 967                         error_page = http_error_page[i];
 968 #endif
 969                         break;
 970                 }
 971         }
 972         /* error message is HTML */
 973         mime_type = responseNum == HTTP_OK ?
 974                                 found_mime_type : "text/html";
 975
 976         if (verbose)
 977                 bb_error_msg("response:%u", responseNum);
 978
 979         /* emit the current date */
 980         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
 981         len = sprintf(iobuf,
 982                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
 983                         "Date: %s\r\nConnection: close\r\n",
 984                         responseNum, responseString, mime_type, tmp_str);
 985
 986 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
 987         if (responseNum == HTTP_UNAUTHORIZED) {
 988                 len += sprintf(iobuf + len,
 989                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
 990                                 g_realm);
 991         }
 992 #endif
 993         if (responseNum == HTTP_MOVED_TEMPORARILY) {
 994                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
 995                                 found_moved_temporarily,
 996                                 (g_query ? "?" : ""),
 997                                 (g_query ? g_query : ""));
 998         }
 999
1000 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1001         if (error_page && access(error_page, R_OK) == 0) {
1002                 strcat(iobuf, "\r\n");
1003                 len += 2;
1004
1005                 if (DEBUG)
1006                         fprintf(stderr, "headers: '%s'\n", iobuf);
1007                 full_write(STDOUT_FILENO, iobuf, len);
1008                 if (DEBUG)
1009                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1010                 return send_file_and_exit(error_page, SEND_BODY);
1011         }
1012 #endif
1013
1014         if (file_size != -1) {    /* file */
1015                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1016 #if ENABLE_FEATURE_HTTPD_RANGES
1017                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1018                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"d-%"OFF_FMT"d/%"OFF_FMT"d\r\n",
1019                                         range_start,
1020                                         range_end,
1021                                         file_size);
1022                         file_size = range_end - range_start + 1;
1023                 }
1024 #endif
1025                 len += sprintf(iobuf + len,
1026 #if ENABLE_FEATURE_HTTPD_RANGES
1027                         "Accept-Ranges: bytes\r\n"
1028 #endif
1029                         "Last-Modified: %s\r\n%s %"OFF_FMT"d\r\n",
1030                                 tmp_str,
1031                                 "Content-length:",
1032                                 file_size
1033                 );
1034         }
1035         iobuf[len++] = '\r';
1036         iobuf[len++] = '\n';
1037         if (infoString) {
1038                 len += sprintf(iobuf + len,
1039                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1040                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1041                                 responseNum, responseString,
1042                                 responseNum, responseString, infoString);
1043         }
1044         if (DEBUG)
1045                 fprintf(stderr, "headers: '%s'\n", iobuf);
1046         if (full_write(STDOUT_FILENO, iobuf, len) != len) {
1047                 if (verbose > 1)
1048                         bb_perror_msg("error");
1049                 log_and_exit();
1050         }
1051 }
1052
1053 static void send_headers_and_exit(int responseNum) NORETURN;
1054 static void send_headers_and_exit(int responseNum)
1055 {
1056         send_headers(responseNum);
1057         log_and_exit();
1058 }
1059
1060 /*
1061  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1062  * '\n' is replaced with NUL.
1063  * Return number of characters read or 0 if nothing is read
1064  * ('\r' and '\n' are not counted).
1065  * Data is returned in iobuf.
1066  */
1067 static int get_line(void)
1068 {
1069         int count = 0;
1070         char c;
1071
1072         while (1) {
1073                 if (hdr_cnt <= 0) {
1074                         hdr_cnt = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1075                         if (hdr_cnt <= 0)
1076                                 break;
1077                         hdr_ptr = hdr_buf;
1078                 }
1079                 iobuf[count] = c = *hdr_ptr++;
1080                 hdr_cnt--;
1081
1082                 if (c == '\r')
1083                         continue;
1084                 if (c == '\n') {
1085                         iobuf[count] = '\0';
1086                         return count;
1087                 }
1088                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1089                         count++;
1090         }
1091         return count;
1092 }
1093
1094 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1095
1096 /* gcc 4.2.1 fares better with NOINLINE */
1097 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) NORETURN;
1098 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1099 {
1100         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1101         struct pollfd pfd[3];
1102         int out_cnt; /* we buffer a bit of initial CGI output */
1103         int count;
1104
1105         /* iobuf is used for CGI -> network data,
1106          * hdr_buf is for network -> CGI data (POSTDATA) */
1107
1108         /* If CGI dies, we still want to correctly finish reading its output
1109          * and send it to the peer. So please no SIGPIPEs! */
1110         signal(SIGPIPE, SIG_IGN);
1111
1112         // We inconsistently handle a case when more POSTDATA from network
1113         // is coming than we expected. We may give *some part* of that
1114         // extra data to CGI.
1115
1116         //if (hdr_cnt > post_len) {
1117         //      /* We got more POSTDATA from network than we expected */
1118         //      hdr_cnt = post_len;
1119         //}
1120         post_len -= hdr_cnt;
1121         /* post_len - number of POST bytes not yet read from network */
1122
1123         /* NB: breaking out of this loop jumps to log_and_exit() */
1124         out_cnt = 0;
1125         while (1) {
1126                 memset(pfd, 0, sizeof(pfd));
1127
1128                 pfd[FROM_CGI].fd = fromCgi_rd;
1129                 pfd[FROM_CGI].events = POLLIN;
1130
1131                 if (toCgi_wr) {
1132                         pfd[TO_CGI].fd = toCgi_wr;
1133                         if (hdr_cnt > 0) {
1134                                 pfd[TO_CGI].events = POLLOUT;
1135                         } else if (post_len > 0) {
1136                                 pfd[0].events = POLLIN;
1137                         } else {
1138                                 /* post_len <= 0 && hdr_cnt <= 0:
1139                                  * no more POST data to CGI,
1140                                  * let CGI see EOF on CGI's stdin */
1141                                 close(toCgi_wr);
1142                                 toCgi_wr = 0;
1143                         }
1144                 }
1145
1146                 /* Now wait on the set of sockets */
1147                 count = safe_poll(pfd, 3, -1);
1148                 if (count <= 0) {
1149 #if 0
1150                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1151                                 /* Weird. CGI didn't exit and no fd's
1152                                  * are ready, yet poll returned?! */
1153                                 continue;
1154                         }
1155                         if (DEBUG && WIFEXITED(status))
1156                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1157                         if (DEBUG && WIFSIGNALED(status))
1158                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1159 #endif
1160                         break;
1161                 }
1162
1163                 if (pfd[TO_CGI].revents) {
1164                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1165                         /* Have data from peer and can write to CGI */
1166                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1167                         /* Doesn't happen, we dont use nonblocking IO here
1168                          *if (count < 0 && errno == EAGAIN) {
1169                          *      ...
1170                          *} else */
1171                         if (count > 0) {
1172                                 hdr_ptr += count;
1173                                 hdr_cnt -= count;
1174                         } else {
1175                                 /* EOF/broken pipe to CGI, stop piping POST data */
1176                                 hdr_cnt = post_len = 0;
1177                         }
1178                 }
1179
1180                 if (pfd[0].revents) {
1181                         /* post_len > 0 && hdr_cnt == 0 here */
1182                         /* We expect data, prev data portion is eaten by CGI
1183                          * and there *is* data to read from the peer
1184                          * (POSTDATA) */
1185                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1186                         //count = safe_read(STDIN_FILENO, hdr_buf, count);
1187                         count = safe_read(STDIN_FILENO, hdr_buf, sizeof(hdr_buf));
1188                         if (count > 0) {
1189                                 hdr_cnt = count;
1190                                 hdr_ptr = hdr_buf;
1191                                 post_len -= count;
1192                         } else {
1193                                 /* no more POST data can be read */
1194                                 post_len = 0;
1195                         }
1196                 }
1197
1198                 if (pfd[FROM_CGI].revents) {
1199                         /* There is something to read from CGI */
1200                         char *rbuf = iobuf;
1201
1202                         /* Are we still buffering CGI output? */
1203                         if (out_cnt >= 0) {
1204                                 /* HTTP_200[] has single "\r\n" at the end.
1205                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1206                                  * CGI scripts MUST send their own header terminated by
1207                                  * empty line, then data. That's why we have only one
1208                                  * <cr><lf> pair here. We will output "200 OK" line
1209                                  * if needed, but CGI still has to provide blank line
1210                                  * between header and body */
1211
1212                                 /* Must use safe_read, not full_read, because
1213                                  * CGI may output a few first bytes and then wait
1214                                  * for POSTDATA without closing stdout.
1215                                  * With full_read we may wait here forever. */
1216                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1217                                 if (count <= 0) {
1218                                         /* eof (or error) and there was no "HTTP",
1219                                          * so write it, then write received data */
1220                                         if (out_cnt) {
1221                                                 full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1);
1222                                                 full_write(STDOUT_FILENO, rbuf, out_cnt);
1223                                         }
1224                                         break; /* CGI stdout is closed, exiting */
1225                                 }
1226                                 out_cnt += count;
1227                                 count = 0;
1228                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1229                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1230                                         /* send "HTTP/1.0 " */
1231                                         if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9)
1232                                                 break;
1233                                         rbuf += 8; /* skip "Status: " */
1234                                         count = out_cnt - 8;
1235                                         out_cnt = -1; /* buffering off */
1236                                 } else if (out_cnt >= 4) {
1237                                         /* Did CGI add "HTTP"? */
1238                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1239                                                 /* there is no "HTTP", do it ourself */
1240                                                 if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1241                                                         break;
1242                                         }
1243                                         /* Commented out:
1244                                         if (!strstr(rbuf, "ontent-")) {
1245                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1246                                         }
1247                                          * Counter-example of valid CGI without Content-type:
1248                                          * echo -en "HTTP/1.0 302 Found\r\n"
1249                                          * echo -en "Location: http://www.busybox.net\r\n"
1250                                          * echo -en "\r\n"
1251                                          */
1252                                         count = out_cnt;
1253                                         out_cnt = -1; /* buffering off */
1254                                 }
1255                         } else {
1256                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1257                                 if (count <= 0)
1258                                         break;  /* eof (or error) */
1259                         }
1260                         if (full_write(STDOUT_FILENO, rbuf, count) != count)
1261                                 break;
1262                         if (DEBUG)
1263                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1264                 } /* if (pfd[FROM_CGI].revents) */
1265         } /* while (1) */
1266         log_and_exit();
1267 }
1268 #endif
1269
1270 #if ENABLE_FEATURE_HTTPD_CGI
1271
1272 static void setenv1(const char *name, const char *value)
1273 {
1274         setenv(name, value ? value : "", 1);
1275 }
1276
1277 /*
1278  * Spawn CGI script, forward CGI's stdin/out <=> network
1279  *
1280  * Environment variables are set up and the script is invoked with pipes
1281  * for stdin/stdout.  If a POST is being done the script is fed the POST
1282  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1283  *
1284  * Parameters:
1285  * const char *url              The requested URL (with leading /).
1286  * int post_len                 Length of the POST body.
1287  * const char *cookie           For set HTTP_COOKIE.
1288  * const char *content_type     For set CONTENT_TYPE.
1289  */
1290 static void send_cgi_and_exit(
1291                 const char *url,
1292                 const char *request,
1293                 int post_len,
1294                 const char *cookie,
1295                 const char *content_type) NORETURN;
1296 static void send_cgi_and_exit(
1297                 const char *url,
1298                 const char *request,
1299                 int post_len,
1300                 const char *cookie,
1301                 const char *content_type)
1302 {
1303         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1304         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1305         char *script;
1306         int pid;
1307
1308         /* Make a copy. NB: caller guarantees:
1309          * url[0] == '/', url[1] != '/' */
1310         url = xstrdup(url);
1311
1312         /*
1313          * We are mucking with environment _first_ and then vfork/exec,
1314          * this allows us to use vfork safely. Parent doesn't care about
1315          * these environment changes anyway.
1316          */
1317
1318         /* Check for [dirs/]script.cgi/PATH_INFO */
1319         script = (char*)url;
1320         while ((script = strchr(script + 1, '/')) != NULL) {
1321                 struct stat sb;
1322
1323                 *script = '\0';
1324                 if (!is_directory(url + 1, 1, &sb)) {
1325                         /* not directory, found script.cgi/PATH_INFO */
1326                         *script = '/';
1327                         break;
1328                 }
1329                 *script = '/'; /* is directory, find next '/' */
1330         }
1331         setenv1("PATH_INFO", script);   /* set to /PATH_INFO or "" */
1332         setenv1("REQUEST_METHOD", request);
1333         if (g_query) {
1334                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", url, g_query));
1335         } else {
1336                 setenv1("REQUEST_URI", url);
1337         }
1338         if (script != NULL)
1339                 *script = '\0';         /* cut off /PATH_INFO */
1340
1341         /* SCRIPT_FILENAME is required by PHP in CGI mode */
1342         if (home_httpd[0] == '/') {
1343                 char *fullpath = concat_path_file(home_httpd, url);
1344                 setenv1("SCRIPT_FILENAME", fullpath);
1345         }
1346         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1347         setenv1("SCRIPT_NAME", url);
1348         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1349          * QUERY_STRING: The information which follows the ? in the URL
1350          * which referenced this script. This is the query information.
1351          * It should not be decoded in any fashion. This variable
1352          * should always be set when there is query information,
1353          * regardless of command line decoding. */
1354         /* (Older versions of bbox seem to do some decoding) */
1355         setenv1("QUERY_STRING", g_query);
1356         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1357         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1358         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1359         /* Having _separate_ variables for IP and port defeats
1360          * the purpose of having socket abstraction. Which "port"
1361          * are you using on Unix domain socket?
1362          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1363          * Oh well... */
1364         {
1365                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1366                 char *cp = strrchr(p, ':');
1367                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1368                         cp = NULL;
1369                 if (cp) *cp = '\0'; /* delete :PORT */
1370                 setenv1("REMOTE_ADDR", p);
1371                 if (cp) {
1372                         *cp = ':';
1373 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1374                         setenv1("REMOTE_PORT", cp + 1);
1375 #endif
1376                 }
1377         }
1378         setenv1("HTTP_USER_AGENT", user_agent);
1379         if (post_len)
1380                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1381         if (cookie)
1382                 setenv1("HTTP_COOKIE", cookie);
1383         if (content_type)
1384                 setenv1("CONTENT_TYPE", content_type);
1385 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1386         if (remoteuser) {
1387                 setenv1("REMOTE_USER", remoteuser);
1388                 putenv((char*)"AUTH_TYPE=Basic");
1389         }
1390 #endif
1391         if (referer)
1392                 setenv1("HTTP_REFERER", referer);
1393
1394         xpiped_pair(fromCgi);
1395         xpiped_pair(toCgi);
1396
1397         pid = vfork();
1398         if (pid < 0) {
1399                 /* TODO: log perror? */
1400                 log_and_exit();
1401         }
1402
1403         if (!pid) {
1404                 /* Child process */
1405                 char *argv[3];
1406
1407                 xfunc_error_retval = 242;
1408
1409                 /* NB: close _first_, then move fds! */
1410                 close(toCgi.wr);
1411                 close(fromCgi.rd);
1412                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1413                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1414                 /* User seeing stderr output can be a security problem.
1415                  * If CGI really wants that, it can always do dup itself. */
1416                 /* dup2(1, 2); */
1417
1418                 /* Chdiring to script's dir */
1419                 script = strrchr(url, '/');
1420                 if (script != url) { /* paranoia */
1421                         *script = '\0';
1422                         if (chdir(url + 1) != 0) {
1423                                 bb_perror_msg("chdir %s", url + 1);
1424                                 goto error_execing_cgi;
1425                         }
1426                         // not needed: *script = '/';
1427                 }
1428                 script++;
1429
1430                 /* set argv[0] to name without path */
1431                 argv[0] = script;
1432                 argv[1] = NULL;
1433
1434 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1435                 {
1436                         char *suffix = strrchr(script, '.');
1437
1438                         if (suffix) {
1439                                 Htaccess *cur;
1440                                 for (cur = script_i; cur; cur = cur->next) {
1441                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1442                                                 /* found interpreter name */
1443                                                 argv[0] = cur->after_colon;
1444                                                 argv[1] = script;
1445                                                 argv[2] = NULL;
1446                                                 break;
1447                                         }
1448                                 }
1449                         }
1450                 }
1451 #endif
1452                 /* restore default signal dispositions for CGI process */
1453                 bb_signals(0
1454                         | (1 << SIGCHLD)
1455                         | (1 << SIGPIPE)
1456                         | (1 << SIGHUP)
1457                         , SIG_DFL);
1458
1459                 /* _NOT_ execvp. We do not search PATH. argv[0] is a filename
1460                  * without any dir components and will only match a file
1461                  * in the current directory */
1462                 execv(argv[0], argv);
1463                 if (verbose)
1464                         bb_perror_msg("exec %s", argv[0]);
1465  error_execing_cgi:
1466                 /* send to stdout
1467                  * (we are CGI here, our stdout is pumped to the net) */
1468                 send_headers_and_exit(HTTP_NOT_FOUND);
1469         } /* end child */
1470
1471         /* Parent process */
1472
1473         /* Restore variables possibly changed by child */
1474         xfunc_error_retval = 0;
1475
1476         /* Pump data */
1477         close(fromCgi.wr);
1478         close(toCgi.rd);
1479         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1480 }
1481
1482 #endif          /* FEATURE_HTTPD_CGI */
1483
1484 /*
1485  * Send a file response to a HTTP request, and exit
1486  *
1487  * Parameters:
1488  * const char *url  The requested URL (with leading /).
1489  * what             What to send (headers/body/both).
1490  */
1491 static void send_file_and_exit(const char *url, int what)
1492 {
1493         static const char *const suffixTable[] = {
1494         /* Warning: shorter equivalent suffix in one line must be first */
1495                 ".htm.html", "text/html",
1496                 ".jpg.jpeg", "image/jpeg",
1497                 ".gif",      "image/gif",
1498                 ".png",      "image/png",
1499                 ".txt.h.c.cc.cpp", "text/plain",
1500                 ".css",      "text/css",
1501                 ".wav",      "audio/wav",
1502                 ".avi",      "video/x-msvideo",
1503                 ".qt.mov",   "video/quicktime",
1504                 ".mpe.mpeg", "video/mpeg",
1505                 ".mid.midi", "audio/midi",
1506                 ".mp3",      "audio/mpeg",
1507 #if 0                        /* unpopular */
1508                 ".au",       "audio/basic",
1509                 ".pac",      "application/x-ns-proxy-autoconfig",
1510                 ".vrml.wrl", "model/vrml",
1511 #endif
1512                 NULL
1513         };
1514
1515         char *suffix;
1516         int f;
1517         const char *const *table;
1518         const char *try_suffix;
1519         ssize_t count;
1520 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1521         off_t offset;
1522 #endif
1523
1524         /* If you want to know about EPIPE below
1525          * (happens if you abort downloads from local httpd): */
1526         signal(SIGPIPE, SIG_IGN);
1527
1528         suffix = strrchr(url, '.');
1529
1530         /* If not found, set default as "application/octet-stream";  */
1531         found_mime_type = "application/octet-stream";
1532         if (suffix) {
1533 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1534                 Htaccess *cur;
1535 #endif
1536                 for (table = suffixTable; *table; table += 2) {
1537                         try_suffix = strstr(table[0], suffix);
1538                         if (try_suffix) {
1539                                 try_suffix += strlen(suffix);
1540                                 if (*try_suffix == '\0' || *try_suffix == '.') {
1541                                         found_mime_type = table[1];
1542                                         break;
1543                                 }
1544                         }
1545                 }
1546 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1547                 for (cur = mime_a; cur; cur = cur->next) {
1548                         if (strcmp(cur->before_colon, suffix) == 0) {
1549                                 found_mime_type = cur->after_colon;
1550                                 break;
1551                         }
1552                 }
1553 #endif
1554         }
1555
1556         if (DEBUG)
1557                 bb_error_msg("sending file '%s' content-type: %s",
1558                         url, found_mime_type);
1559
1560         f = open(url, O_RDONLY);
1561         if (f < 0) {
1562                 if (DEBUG)
1563                         bb_perror_msg("cannot open '%s'", url);
1564                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1565                  * IOW: it is unsafe to call send_headers_and_exit
1566                  * if what is SEND_BODY! Can recurse! */
1567                 if (what != SEND_BODY)
1568                         send_headers_and_exit(HTTP_NOT_FOUND);
1569                 log_and_exit();
1570         }
1571 #if ENABLE_FEATURE_HTTPD_RANGES
1572         if (what == SEND_BODY)
1573                 range_start = 0; /* err pages and ranges don't mix */
1574         range_len = MAXINT(off_t);
1575         if (range_start) {
1576                 if (!range_end) {
1577                         range_end = file_size - 1;
1578                 }
1579                 if (range_end < range_start
1580                  || lseek(f, range_start, SEEK_SET) != range_start
1581                 ) {
1582                         lseek(f, 0, SEEK_SET);
1583                         range_start = 0;
1584                 } else {
1585                         range_len = range_end - range_start + 1;
1586                         send_headers(HTTP_PARTIAL_CONTENT);
1587                         what = SEND_BODY;
1588                 }
1589         }
1590 #endif
1591
1592         if (what & SEND_HEADERS)
1593                 send_headers(HTTP_OK);
1594
1595 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1596         offset = range_start;
1597         do {
1598                 /* sz is rounded down to 64k */
1599                 ssize_t sz = MAXINT(ssize_t) - 0xffff;
1600                 USE_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1601                 count = sendfile(1, f, &offset, sz);
1602                 if (count < 0) {
1603                         if (offset == range_start)
1604                                 goto fallback;
1605                         goto fin;
1606                 }
1607                 USE_FEATURE_HTTPD_RANGES(range_len -= sz;)
1608         } while (count > 0 && range_len);
1609         log_and_exit();
1610
1611  fallback:
1612 #endif
1613         while ((count = safe_read(f, iobuf, IOBUF_SIZE)) > 0) {
1614                 ssize_t n;
1615                 USE_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1616                 n = full_write(STDOUT_FILENO, iobuf, count);
1617                 if (count != n)
1618                         break;
1619                 USE_FEATURE_HTTPD_RANGES(range_len -= count;)
1620                 if (!range_len)
1621                         break;
1622         }
1623 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1624  fin:
1625 #endif
1626         if (count < 0 && verbose > 1)
1627                 bb_perror_msg("error");
1628         log_and_exit();
1629 }
1630
1631 static int checkPermIP(void)
1632 {
1633         Htaccess_IP *cur;
1634
1635         for (cur = ip_a_d; cur; cur = cur->next) {
1636 #if DEBUG
1637                 fprintf(stderr,
1638                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1639                         rmt_ip_str,
1640                         (unsigned char)(cur->ip >> 24),
1641                         (unsigned char)(cur->ip >> 16),
1642                         (unsigned char)(cur->ip >> 8),
1643                         (unsigned char)(cur->ip),
1644                         (unsigned char)(cur->mask >> 24),
1645                         (unsigned char)(cur->mask >> 16),
1646                         (unsigned char)(cur->mask >> 8),
1647                         (unsigned char)(cur->mask)
1648                 );
1649 #endif
1650                 if ((rmt_ip & cur->mask) == cur->ip)
1651                         return (cur->allow_deny == 'A'); /* A -> 1 */
1652         }
1653
1654         return !flg_deny_all; /* depends on whether we saw "D:*" */
1655 }
1656
1657 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1658 /*
1659  * Config file entries are of the form "/<path>:<user>:<passwd>".
1660  * If config file has no prefix match for path, access is allowed.
1661  *
1662  * path                 The file path
1663  * user_and_passwd      "user:passwd" to validate
1664  *
1665  * Returns 1 if user_and_passwd is OK.
1666  */
1667 static int check_user_passwd(const char *path, const char *user_and_passwd)
1668 {
1669         Htaccess *cur;
1670         const char *prev = NULL;
1671
1672         for (cur = g_auth; cur; cur = cur->next) {
1673                 const char *dir_prefix;
1674                 size_t len;
1675
1676                 dir_prefix = cur->before_colon;
1677
1678                 /* WHY? */
1679                 /* If already saw a match, don't accept other different matches */
1680                 if (prev && strcmp(prev, dir_prefix) != 0)
1681                         continue;
1682
1683                 if (DEBUG)
1684                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", dir_prefix, user_and_passwd);
1685
1686                 /* If it's not a prefix match, continue searching */
1687                 len = strlen(dir_prefix);
1688                 if (len != 1 /* dir_prefix "/" matches all, don't need to check */
1689                  && (strncmp(dir_prefix, path, len) != 0
1690                     || (path[len] != '/' && path[len] != '\0'))
1691                 ) {
1692                         continue;
1693                 }
1694
1695                 /* Path match found */
1696                 prev = dir_prefix;
1697
1698                 if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1699                         char *md5_passwd;
1700
1701                         md5_passwd = strchr(cur->after_colon, ':');
1702                         if (md5_passwd && md5_passwd[1] == '$' && md5_passwd[2] == '1'
1703                          && md5_passwd[3] == '$' && md5_passwd[4]
1704                         ) {
1705                                 char *encrypted;
1706                                 int r, user_len_p1;
1707
1708                                 md5_passwd++;
1709                                 user_len_p1 = md5_passwd - cur->after_colon;
1710                                 /* comparing "user:" */
1711                                 if (strncmp(cur->after_colon, user_and_passwd, user_len_p1) != 0) {
1712                                         continue;
1713                                 }
1714
1715                                 encrypted = pw_encrypt(
1716                                         user_and_passwd + user_len_p1 /* cleartext pwd from user */,
1717                                         md5_passwd /*salt */, 1 /* cleanup */);
1718                                 r = strcmp(encrypted, md5_passwd);
1719                                 free(encrypted);
1720                                 if (r == 0)
1721                                         goto set_remoteuser_var; /* Ok */
1722                                 continue;
1723                         }
1724                 }
1725
1726                 /* Comparing plaintext "user:pass" in one go */
1727                 if (strcmp(cur->after_colon, user_and_passwd) == 0) {
1728  set_remoteuser_var:
1729                         remoteuser = xstrndup(user_and_passwd,
1730                                         strchrnul(user_and_passwd, ':') - user_and_passwd);
1731                         return 1; /* Ok */
1732                 }
1733         } /* for */
1734
1735         /* 0(bad) if prev is set: matches were found but passwd was wrong */
1736         return (prev == NULL);
1737 }
1738 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1739
1740 #if ENABLE_FEATURE_HTTPD_PROXY
1741 static Htaccess_Proxy *find_proxy_entry(const char *url)
1742 {
1743         Htaccess_Proxy *p;
1744         for (p = proxy; p; p = p->next) {
1745                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1746                         return p;
1747         }
1748         return NULL;
1749 }
1750 #endif
1751
1752 /*
1753  * Handle timeouts
1754  */
1755 static void exit_on_signal(int sig) NORETURN;
1756 static void exit_on_signal(int sig UNUSED_PARAM)
1757 {
1758         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1759 }
1760
1761 /*
1762  * Handle an incoming http request and exit.
1763  */
1764 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) NORETURN;
1765 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1766 {
1767         static const char request_GET[] ALIGN1 = "GET";
1768         struct stat sb;
1769         char *urlcopy;
1770         char *urlp;
1771         char *tptr;
1772 #if ENABLE_FEATURE_HTTPD_CGI
1773         static const char request_HEAD[] ALIGN1 = "HEAD";
1774         const char *prequest;
1775         char *cookie = NULL;
1776         char *content_type = NULL;
1777         unsigned long length = 0;
1778 #elif ENABLE_FEATURE_HTTPD_PROXY
1779 #define prequest request_GET
1780         unsigned long length = 0;
1781 #endif
1782 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1783         smallint authorized = -1;
1784 #endif
1785         smallint ip_allowed;
1786         char http_major_version;
1787 #if ENABLE_FEATURE_HTTPD_PROXY
1788         char http_minor_version;
1789         char *header_buf = header_buf; /* for gcc */
1790         char *header_ptr = header_ptr;
1791         Htaccess_Proxy *proxy_entry;
1792 #endif
1793
1794         /* Allocation of iobuf is postponed until now
1795          * (IOW, server process doesn't need to waste 8k) */
1796         iobuf = xmalloc(IOBUF_SIZE);
1797
1798         rmt_ip = 0;
1799         if (fromAddr->u.sa.sa_family == AF_INET) {
1800                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1801         }
1802 #if ENABLE_FEATURE_IPV6
1803         if (fromAddr->u.sa.sa_family == AF_INET6
1804          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1805          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1806          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1807                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1808 #endif
1809         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1810                 /* NB: can be NULL (user runs httpd -i by hand?) */
1811                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1812         }
1813         if (verbose) {
1814                 /* this trick makes -v logging much simpler */
1815                 if (rmt_ip_str)
1816                         applet_name = rmt_ip_str;
1817                 if (verbose > 2)
1818                         bb_error_msg("connected");
1819         }
1820
1821         /* Install timeout handler */
1822         signal_no_SA_RESTART_empty_mask(SIGALRM, exit_on_signal);
1823         alarm(HEADER_READ_TIMEOUT);
1824
1825         if (!get_line()) /* EOF or error or empty line */
1826                 send_headers_and_exit(HTTP_BAD_REQUEST);
1827
1828         /* Determine type of request (GET/POST) */
1829         urlp = strpbrk(iobuf, " \t");
1830         if (urlp == NULL)
1831                 send_headers_and_exit(HTTP_BAD_REQUEST);
1832         *urlp++ = '\0';
1833 #if ENABLE_FEATURE_HTTPD_CGI
1834         prequest = request_GET;
1835         if (strcasecmp(iobuf, prequest) != 0) {
1836                 prequest = request_HEAD;
1837                 if (strcasecmp(iobuf, prequest) != 0) {
1838                         prequest = "POST";
1839                         if (strcasecmp(iobuf, prequest) != 0)
1840                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1841                 }
1842         }
1843 #else
1844         if (strcasecmp(iobuf, request_GET) != 0)
1845                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1846 #endif
1847         urlp = skip_whitespace(urlp);
1848         if (urlp[0] != '/')
1849                 send_headers_and_exit(HTTP_BAD_REQUEST);
1850
1851         /* Find end of URL and parse HTTP version, if any */
1852         http_major_version = '0';
1853         USE_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1854         tptr = strchrnul(urlp, ' ');
1855         /* Is it " HTTP/"? */
1856         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1857                 http_major_version = tptr[6];
1858                 USE_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1859         }
1860         *tptr = '\0';
1861
1862         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1863         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1864         /*if (urlcopy == NULL)
1865          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1866         strcpy(urlcopy, urlp);
1867         /* NB: urlcopy ptr is never changed after this */
1868
1869         /* Extract url args if present */
1870         g_query = NULL;
1871         tptr = strchr(urlcopy, '?');
1872         if (tptr) {
1873                 *tptr++ = '\0';
1874                 g_query = tptr;
1875         }
1876
1877         /* Decode URL escape sequences */
1878         tptr = decodeString(urlcopy, 0);
1879         if (tptr == NULL)
1880                 send_headers_and_exit(HTTP_BAD_REQUEST);
1881         if (tptr == urlcopy + 1) {
1882                 /* '/' or NUL is encoded */
1883                 send_headers_and_exit(HTTP_NOT_FOUND);
1884         }
1885
1886         /* Canonicalize path */
1887         /* Algorithm stolen from libbb bb_simplify_path(),
1888          * but don't strdup, retain trailing slash, protect root */
1889         urlp = tptr = urlcopy;
1890         do {
1891                 if (*urlp == '/') {
1892                         /* skip duplicate (or initial) slash */
1893                         if (*tptr == '/') {
1894                                 continue;
1895                         }
1896                         if (*tptr == '.') {
1897                                 /* skip extra "/./" */
1898                                 if (tptr[1] == '/' || !tptr[1]) {
1899                                         continue;
1900                                 }
1901                                 /* "..": be careful */
1902                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1903                                         ++tptr;
1904                                         if (urlp == urlcopy) /* protect root */
1905                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1906                                         while (*--urlp != '/') /* omit previous dir */;
1907                                                 continue;
1908                                 }
1909                         }
1910                 }
1911                 *++urlp = *tptr;
1912         } while (*++tptr);
1913         *++urlp = '\0';       /* terminate after last character */
1914
1915         /* If URL is a directory, add '/' */
1916         if (urlp[-1] != '/') {
1917                 if (is_directory(urlcopy + 1, 1, &sb)) {
1918                         found_moved_temporarily = urlcopy;
1919                 }
1920         }
1921
1922         /* Log it */
1923         if (verbose > 1)
1924                 bb_error_msg("url:%s", urlcopy);
1925
1926         tptr = urlcopy;
1927         ip_allowed = checkPermIP();
1928         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1929                 /* have path1/path2 */
1930                 *tptr = '\0';
1931                 if (is_directory(urlcopy + 1, 1, &sb)) {
1932                         /* may have subdir config */
1933                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1934                         ip_allowed = checkPermIP();
1935                 }
1936                 *tptr = '/';
1937         }
1938
1939 #if ENABLE_FEATURE_HTTPD_PROXY
1940         proxy_entry = find_proxy_entry(urlcopy);
1941         if (proxy_entry)
1942                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1943 #endif
1944
1945         if (http_major_version >= '0') {
1946                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1947
1948                 /* Read until blank line for HTTP version specified, else parse immediate */
1949                 while (1) {
1950                         alarm(HEADER_READ_TIMEOUT);
1951                         if (!get_line())
1952                                 break; /* EOF or error or empty line */
1953                         if (DEBUG)
1954                                 bb_error_msg("header: '%s'", iobuf);
1955
1956 #if ENABLE_FEATURE_HTTPD_PROXY
1957                         /* We need 2 more bytes for yet another "\r\n" -
1958                          * see near fdprintf(proxy_fd...) further below */
1959                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1960                                 int len = strlen(iobuf);
1961                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1962                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1963                                 memcpy(header_ptr, iobuf, len);
1964                                 header_ptr += len;
1965                                 header_ptr[0] = '\r';
1966                                 header_ptr[1] = '\n';
1967                                 header_ptr += 2;
1968                         }
1969 #endif
1970
1971 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1972                         /* Try and do our best to parse more lines */
1973                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1974                                 /* extra read only for POST */
1975                                 if (prequest != request_GET
1976 #if ENABLE_FEATURE_HTTPD_CGI
1977                                  && prequest != request_HEAD
1978 #endif
1979                                 ) {
1980                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1981                                         if (!tptr[0])
1982                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1983                                         /* not using strtoul: it ignores leading minus! */
1984                                         length = bb_strtou(tptr, NULL, 10);
1985                                         /* length is "ulong", but we need to pass it to int later */
1986                                         if (errno || length > INT_MAX)
1987                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1988                                 }
1989                         }
1990 #endif
1991 #if ENABLE_FEATURE_HTTPD_CGI
1992                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
1993                                 cookie = xstrdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
1994                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
1995                                 content_type = xstrdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
1996                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
1997                                 referer = xstrdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
1998                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
1999                                 user_agent = xstrdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2000                         }
2001 #endif
2002 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2003                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2004                                 /* We only allow Basic credentials.
2005                                  * It shows up as "Authorization: Basic <user>:<passwd>" where
2006                                  * "<user>:<passwd>" is base64 encoded.
2007                                  */
2008                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2009                                 if (STRNCASECMP(tptr, "Basic") != 0)
2010                                         continue;
2011                                 tptr += sizeof("Basic")-1;
2012                                 /* decodeBase64() skips whitespace itself */
2013                                 decodeBase64(tptr);
2014                                 authorized = check_user_passwd(urlcopy, tptr);
2015                         }
2016 #endif
2017 #if ENABLE_FEATURE_HTTPD_RANGES
2018                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2019                                 /* We know only bytes=NNN-[MMM] */
2020                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2021                                 if (strncmp(s, "bytes=", 6) == 0) {
2022                                         s += sizeof("bytes=")-1;
2023                                         range_start = BB_STRTOOFF(s, &s, 10);
2024                                         if (s[0] != '-' || range_start < 0) {
2025                                                 range_start = 0;
2026                                         } else if (s[1]) {
2027                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2028                                                 if (errno || range_end < range_start)
2029                                                         range_start = 0;
2030                                         }
2031                                 }
2032                         }
2033 #endif
2034                 } /* while extra header reading */
2035         }
2036
2037         /* We are done reading headers, disable peer timeout */
2038         alarm(0);
2039
2040         if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || !ip_allowed) {
2041                 /* protect listing [/path]/httpd_conf or IP deny */
2042                 send_headers_and_exit(HTTP_FORBIDDEN);
2043         }
2044
2045 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2046         /* Case: no "Authorization:" was seen, but page does require passwd.
2047          * Check that with dummy user:pass */
2048         if (authorized < 0)
2049                 authorized = check_user_passwd(urlcopy, ":");
2050         if (!authorized)
2051                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2052 #endif
2053
2054         if (found_moved_temporarily) {
2055                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2056         }
2057
2058 #if ENABLE_FEATURE_HTTPD_PROXY
2059         if (proxy_entry != NULL) {
2060                 int proxy_fd;
2061                 len_and_sockaddr *lsa;
2062
2063                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2064                 if (proxy_fd < 0)
2065                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2066                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2067                 if (lsa == NULL)
2068                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2069                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2070                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2071                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2072                                 prequest, /* GET or POST */
2073                                 proxy_entry->url_to, /* url part 1 */
2074                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2075                                 (g_query ? "?" : ""), /* "?" (maybe) */
2076                                 (g_query ? g_query : ""), /* query string (maybe) */
2077                                 http_major_version, http_minor_version);
2078                 header_ptr[0] = '\r';
2079                 header_ptr[1] = '\n';
2080                 header_ptr += 2;
2081                 write(proxy_fd, header_buf, header_ptr - header_buf);
2082                 free(header_buf); /* on the order of 8k, free it */
2083                 /* cgi_io_loop_and_exit needs to have two disctinct fds */
2084                 cgi_io_loop_and_exit(proxy_fd, dup(proxy_fd), length);
2085         }
2086 #endif
2087
2088         tptr = urlcopy + 1;      /* skip first '/' */
2089
2090 #if ENABLE_FEATURE_HTTPD_CGI
2091         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2092                 if (tptr[8] == '\0') {
2093                         /* protect listing "cgi-bin/" */
2094                         send_headers_and_exit(HTTP_FORBIDDEN);
2095                 }
2096                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2097         }
2098 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2099         {
2100                 char *suffix = strrchr(tptr, '.');
2101                 if (suffix) {
2102                         Htaccess *cur;
2103                         for (cur = script_i; cur; cur = cur->next) {
2104                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2105                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2106                                 }
2107                         }
2108                 }
2109         }
2110 #endif
2111         if (prequest != request_GET && prequest != request_HEAD) {
2112                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2113         }
2114 #endif  /* FEATURE_HTTPD_CGI */
2115
2116         if (urlp[-1] == '/')
2117                 strcpy(urlp, index_page);
2118         if (stat(tptr, &sb) == 0) {
2119                 file_size = sb.st_size;
2120                 last_mod = sb.st_mtime;
2121         }
2122 #if ENABLE_FEATURE_HTTPD_CGI
2123         else if (urlp[-1] == '/') {
2124                 /* It's a dir URL and there is no index.html
2125                  * Try cgi-bin/index.cgi */
2126                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2127                         urlp[0] = '\0';
2128                         g_query = urlcopy;
2129                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2130                 }
2131         }
2132 #endif
2133         /* else {
2134          *      fall through to send_file, it errors out if open fails
2135          * }
2136          */
2137
2138         send_file_and_exit(tptr,
2139 #if ENABLE_FEATURE_HTTPD_CGI
2140                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2141 #else
2142                 SEND_HEADERS_AND_BODY
2143 #endif
2144         );
2145 }
2146
2147 /*
2148  * The main http server function.
2149  * Given a socket, listen for new connections and farm out
2150  * the processing as a [v]forked process.
2151  * Never returns.
2152  */
2153 #if BB_MMU
2154 static void mini_httpd(int server_socket) NORETURN;
2155 static void mini_httpd(int server_socket)
2156 {
2157         /* NB: it's best to not use xfuncs in this loop before fork().
2158          * Otherwise server may die on transient errors (temporary
2159          * out-of-memory condition, etc), which is Bad(tm).
2160          * Try to do any dangerous calls after fork.
2161          */
2162         while (1) {
2163                 int n;
2164                 len_and_sockaddr fromAddr;
2165
2166                 /* Wait for connections... */
2167                 fromAddr.len = LSA_SIZEOF_SA;
2168                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2169
2170                 if (n < 0)
2171                         continue;
2172                 /* set the KEEPALIVE option to cull dead connections */
2173                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2174
2175                 if (fork() == 0) {
2176                         /* child */
2177 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2178                         /* Do not reload config on HUP */
2179                         signal(SIGHUP, SIG_IGN);
2180 #endif
2181                         close(server_socket);
2182                         xmove_fd(n, 0);
2183                         xdup2(0, 1);
2184
2185                         handle_incoming_and_exit(&fromAddr);
2186                 }
2187                 /* parent, or fork failed */
2188                 close(n);
2189         } /* while (1) */
2190         /* never reached */
2191 }
2192 #else
2193 static void mini_httpd_nommu(int server_socket, int argc, char **argv) NORETURN;
2194 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2195 {
2196         char *argv_copy[argc + 2];
2197
2198         argv_copy[0] = argv[0];
2199         argv_copy[1] = (char*)"-i";
2200         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2201
2202         /* NB: it's best to not use xfuncs in this loop before vfork().
2203          * Otherwise server may die on transient errors (temporary
2204          * out-of-memory condition, etc), which is Bad(tm).
2205          * Try to do any dangerous calls after fork.
2206          */
2207         while (1) {
2208                 int n;
2209                 len_and_sockaddr fromAddr;
2210
2211                 /* Wait for connections... */
2212                 fromAddr.len = LSA_SIZEOF_SA;
2213                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2214
2215                 if (n < 0)
2216                         continue;
2217                 /* set the KEEPALIVE option to cull dead connections */
2218                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2219
2220                 if (vfork() == 0) {
2221                         /* child */
2222 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2223                         /* Do not reload config on HUP */
2224                         signal(SIGHUP, SIG_IGN);
2225 #endif
2226                         close(server_socket);
2227                         xmove_fd(n, 0);
2228                         xdup2(0, 1);
2229
2230                         /* Run a copy of ourself in inetd mode */
2231                         re_exec(argv_copy);
2232                 }
2233                 /* parent, or vfork failed */
2234                 close(n);
2235         } /* while (1) */
2236         /* never reached */
2237 }
2238 #endif
2239
2240 /*
2241  * Process a HTTP connection on stdin/out.
2242  * Never returns.
2243  */
2244 static void mini_httpd_inetd(void) NORETURN;
2245 static void mini_httpd_inetd(void)
2246 {
2247         len_and_sockaddr fromAddr;
2248
2249         memset(&fromAddr, 0, sizeof(fromAddr));
2250         fromAddr.len = LSA_SIZEOF_SA;
2251         /* NB: can fail if user runs it by hand and types in http cmds */
2252         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2253         handle_incoming_and_exit(&fromAddr);
2254 }
2255
2256 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2257 static void sighup_handler(int sig)
2258 {
2259         parse_conf(default_path_httpd_conf, sig == SIGHUP ? SIGNALED_PARSE : FIRST_PARSE);
2260
2261         signal_SA_RESTART_empty_mask(SIGHUP, sighup_handler);
2262 }
2263 #endif
2264
2265 enum {
2266         c_opt_config_file = 0,
2267         d_opt_decode_url,
2268         h_opt_home_httpd,
2269         USE_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2270         USE_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2271         USE_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2272         USE_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2273         p_opt_port      ,
2274         p_opt_inetd     ,
2275         p_opt_foreground,
2276         p_opt_verbose   ,
2277         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2278         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2279         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2280         OPT_ENCODE_URL  = USE_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2281         OPT_REALM       = USE_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2282         OPT_MD5         = USE_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2283         OPT_SETUID      = USE_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2284         OPT_PORT        = 1 << p_opt_port,
2285         OPT_INETD       = 1 << p_opt_inetd,
2286         OPT_FOREGROUND  = 1 << p_opt_foreground,
2287         OPT_VERBOSE     = 1 << p_opt_verbose,
2288 };
2289
2290
2291 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2292 int httpd_main(int argc UNUSED_PARAM, char **argv)
2293 {
2294         int server_socket = server_socket; /* for gcc */
2295         unsigned opt;
2296         char *url_for_decode;
2297         USE_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2298         USE_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2299         USE_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2300         USE_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2301
2302         INIT_G();
2303
2304 #if ENABLE_LOCALE_SUPPORT
2305         /* Undo busybox.c: we want to speak English in http (dates etc) */
2306         setlocale(LC_TIME, "C");
2307 #endif
2308
2309         home_httpd = xrealloc_getcwd_or_warn(NULL);
2310         /* -v counts, -i implies -f */
2311         opt_complementary = "vv:if";
2312         /* We do not "absolutize" path given by -h (home) opt.
2313          * If user gives relative path in -h,
2314          * $SCRIPT_FILENAME will not be set. */
2315         opt = getopt32(argv, "c:d:h:"
2316                         USE_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2317                         USE_FEATURE_HTTPD_BASIC_AUTH("r:")
2318                         USE_FEATURE_HTTPD_AUTH_MD5("m:")
2319                         USE_FEATURE_HTTPD_SETUID("u:")
2320                         "p:ifv",
2321                         &configFile, &url_for_decode, &home_httpd
2322                         USE_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2323                         USE_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2324                         USE_FEATURE_HTTPD_AUTH_MD5(, &pass)
2325                         USE_FEATURE_HTTPD_SETUID(, &s_ugid)
2326                         , &bind_addr_or_port
2327                         , &verbose
2328                 );
2329         if (opt & OPT_DECODE_URL) {
2330                 fputs(decodeString(url_for_decode, 1), stdout);
2331                 return 0;
2332         }
2333 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2334         if (opt & OPT_ENCODE_URL) {
2335                 fputs(encodeString(url_for_encode), stdout);
2336                 return 0;
2337         }
2338 #endif
2339 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2340         if (opt & OPT_MD5) {
2341                 puts(pw_encrypt(pass, "$1$", 1));
2342                 return 0;
2343         }
2344 #endif
2345 #if ENABLE_FEATURE_HTTPD_SETUID
2346         if (opt & OPT_SETUID) {
2347                 if (!get_uidgid(&ugid, s_ugid, 1))
2348                         bb_error_msg_and_die("unknown user[:group] "
2349                                                 "name '%s'", s_ugid);
2350         }
2351 #endif
2352
2353 #if !BB_MMU
2354         if (!(opt & OPT_FOREGROUND)) {
2355                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2356         }
2357 #endif
2358
2359         xchdir(home_httpd);
2360         if (!(opt & OPT_INETD)) {
2361                 signal(SIGCHLD, SIG_IGN);
2362                 server_socket = openServer();
2363 #if ENABLE_FEATURE_HTTPD_SETUID
2364                 /* drop privileges */
2365                 if (opt & OPT_SETUID) {
2366                         if (ugid.gid != (gid_t)-1) {
2367                                 if (setgroups(1, &ugid.gid) == -1)
2368                                         bb_perror_msg_and_die("setgroups");
2369                                 xsetgid(ugid.gid);
2370                         }
2371                         xsetuid(ugid.uid);
2372                 }
2373 #endif
2374         }
2375
2376 #if 0 /*was #if ENABLE_FEATURE_HTTPD_CGI*/
2377         /* User can do it himself: 'env - PATH="$PATH" httpd'
2378          * We don't do it because we don't want to screw users
2379          * which want to do
2380          * 'env - VAR1=val1 VAR2=val2 httpd'
2381          * and have VAR1 and VAR2 values visible in their CGIs.
2382          * Besides, it is also smaller. */
2383         {
2384                 char *p = getenv("PATH");
2385                 /* env strings themself are not freed, no need to xstrdup(p): */
2386                 clearenv();
2387                 if (p)
2388                         putenv(p - 5);
2389 //              if (!(opt & OPT_INETD))
2390 //                      setenv_long("SERVER_PORT", ???);
2391         }
2392 #endif
2393
2394 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2395         if (!(opt & OPT_INETD))
2396                 sighup_handler(0);
2397 #endif
2398         parse_conf(default_path_httpd_conf, FIRST_PARSE);
2399
2400         xfunc_error_retval = 0;
2401         if (opt & OPT_INETD)
2402                 mini_httpd_inetd();
2403 #if BB_MMU
2404         if (!(opt & OPT_FOREGROUND))
2405                 bb_daemonize(0); /* don't change current directory */
2406         mini_httpd(server_socket); /* never returns */
2407 #else
2408         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2409 #endif
2410         /* return 0; */
2411 }