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