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