networking/httpd.c

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