Initial public busybox upstream commit
[busybox4maemo] / networking / httpd.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * httpd implementation for busybox
4  *
5  * Copyright (C) 2002,2003 Glenn Engel <glenne@engel.org>
6  * Copyright (C) 2003-2006 Vladimir Oleynik <dzo@simtreas.ru>
7  *
8  * simplify patch stolen from libbb without using strdup
9  *
10  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
11  *
12  *****************************************************************************
13  *
14  * Typical usage:
15  *   for non root user
16  * httpd -p 8080 -h $HOME/public_html
17  *   or for daemon start from rc script with uid=0:
18  * httpd -u www
19  * This is equivalent if www user have uid=80 to
20  * httpd -p 80 -u 80 -h /www -c /etc/httpd.conf -r "Web Server Authentication"
21  *
22  *
23  * When a url starts by "/cgi-bin/" it is assumed to be a cgi script.  The
24  * server changes directory to the location of the script and executes it
25  * after setting QUERY_STRING and other environment variables.
26  *
27  * Doc:
28  * "CGI Environment Variables": http://hoohoo.ncsa.uiuc.edu/cgi/env.html
29  *
30  * The server can also be invoked as a url arg decoder and html text encoder
31  * as follows:
32  *  foo=`httpd -d $foo`           # decode "Hello%20World" as "Hello World"
33  *  bar=`httpd -e "<Hello World>"`  # encode as "&#60Hello&#32World&#62"
34  * Note that url encoding for arguments is not the same as html encoding for
35  * presentation.  -d decodes a url-encoded argument while -e encodes in html
36  * for page display.
37  *
38  * httpd.conf has the following format:
39  *
40  * A:172.20.         # Allow address from 172.20.0.0/16
41  * A:10.0.0.0/25     # Allow any address from 10.0.0.0-10.0.0.127
42  * A:10.0.0.0/255.255.255.128  # Allow any address that previous set
43  * A:127.0.0.1       # Allow local loopback connections
44  * D:*               # Deny from other IP connections
45  * E404:/path/e404.html # /path/e404.html is the 404 (not found) error page
46  * I:index.html      # Show index.html when a directory is requested
47  *
48  * P:/url:[http://]hostname[:port]/new/path
49  *                   # When /urlXXXXXX is requested, reverse proxy
50  *                   # it to http://hostname[:port]/new/pathXXXXXX
51  *
52  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
53  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
54  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
55  * .au:audio/basic   # additional mime type for audio.au files
56  * *.php:/path/php   # running cgi.php scripts through an interpreter
57  *
58  * A/D may be as a/d or allow/deny - first char case insensitive
59  * Deny IP rules take precedence over allow rules.
60  *
61  *
62  * The Deny/Allow IP logic:
63  *
64  *  - Default is to allow all.  No addresses are denied unless
65  *         denied with a D: rule.
66  *  - Order of Deny/Allow rules is significant
67  *  - Deny rules take precedence over allow rules.
68  *  - If a deny all rule (D:*) is used it acts as a catch-all for unmatched
69  *       addresses.
70  *  - Specification of Allow all (A:*) is a no-op
71  *
72  * Example:
73  *   1. Allow only specified addresses
74  *     A:172.20          # Allow any address that begins with 172.20.
75  *     A:10.10.          # Allow any address that begins with 10.10.
76  *     A:127.0.0.1       # Allow local loopback connections
77  *     D:*               # Deny from other IP connections
78  *
79  *   2. Only deny specified addresses
80  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
81  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
82  *     A:*             # (optional line added for clarity)
83  *
84  * If a sub directory contains a config file it is parsed and merged with
85  * any existing settings as if it was appended to the original configuration.
86  *
87  * subdir paths are relative to the containing subdir and thus cannot
88  * affect the parent rules.
89  *
90  * Note that since the sub dir is parsed in the forked thread servicing the
91  * subdir http request, any merge is discarded when the process exits.  As a
92  * result, the subdir settings only have a lifetime of a single request.
93  *
94  * Custom error pages can contain an absolute path or be relative to
95  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
96  * page can only be defined in the root configuration file and are not taken
97  * into account in local (directories) config files.
98  *
99  * If -c is not set, an attempt will be made to open the default
100  * root configuration file.  If -c is set and the file is not found, the
101  * server exits with an error.
102  *
103  */
104
105 #include "libbb.h"
106 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
107 #include <sys/sendfile.h>
108 #endif
109
110 //#define DEBUG 1
111 #define DEBUG 0
112
113 #define IOBUF_SIZE 8192    /* IO buffer */
114
115 /* amount of buffering in a pipe */
116 #ifndef PIPE_BUF
117 # define PIPE_BUF 4096
118 #endif
119 #if PIPE_BUF >= IOBUF_SIZE
120 # error "PIPE_BUF >= IOBUF_SIZE"
121 #endif
122
123 #define HEADER_READ_TIMEOUT 60
124
125 static const char default_path_httpd_conf[] ALIGN1 = "/etc";
126 static const char httpd_conf[] ALIGN1 = "httpd.conf";
127 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
128
129 typedef struct has_next_ptr {
130         struct has_next_ptr *next;
131 } has_next_ptr;
132
133 /* Must have "next" as a first member */
134 typedef struct Htaccess {
135         struct Htaccess *next;
136         char *after_colon;
137         char before_colon[1];  /* really bigger, must be last */
138 } Htaccess;
139
140 /* Must have "next" as a first member */
141 typedef struct Htaccess_IP {
142         struct Htaccess_IP *next;
143         unsigned ip;
144         unsigned mask;
145         int allow_deny;
146 } Htaccess_IP;
147
148 /* Must have "next" as a first member */
149 typedef struct Htaccess_Proxy {
150         struct Htaccess_Proxy *next;
151         char *url_from;
152         char *host_port;
153         char *url_to;
154 } Htaccess_Proxy;
155
156 enum {
157         HTTP_OK = 200,
158         HTTP_PARTIAL_CONTENT = 206,
159         HTTP_MOVED_TEMPORARILY = 302,
160         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
161         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
162         HTTP_NOT_FOUND = 404,
163         HTTP_FORBIDDEN = 403,
164         HTTP_REQUEST_TIMEOUT = 408,
165         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
166         HTTP_INTERNAL_SERVER_ERROR = 500,
167         HTTP_CONTINUE = 100,
168 #if 0   /* future use */
169         HTTP_SWITCHING_PROTOCOLS = 101,
170         HTTP_CREATED = 201,
171         HTTP_ACCEPTED = 202,
172         HTTP_NON_AUTHORITATIVE_INFO = 203,
173         HTTP_NO_CONTENT = 204,
174         HTTP_MULTIPLE_CHOICES = 300,
175         HTTP_MOVED_PERMANENTLY = 301,
176         HTTP_NOT_MODIFIED = 304,
177         HTTP_PAYMENT_REQUIRED = 402,
178         HTTP_BAD_GATEWAY = 502,
179         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
180         HTTP_RESPONSE_SETSIZE = 0xffffffff
181 #endif
182 };
183
184 static const uint16_t http_response_type[] ALIGN2 = {
185         HTTP_OK,
186 #if ENABLE_FEATURE_HTTPD_RANGES
187         HTTP_PARTIAL_CONTENT,
188 #endif
189         HTTP_MOVED_TEMPORARILY,
190         HTTP_REQUEST_TIMEOUT,
191         HTTP_NOT_IMPLEMENTED,
192 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
193         HTTP_UNAUTHORIZED,
194 #endif
195         HTTP_NOT_FOUND,
196         HTTP_BAD_REQUEST,
197         HTTP_FORBIDDEN,
198         HTTP_INTERNAL_SERVER_ERROR,
199 #if 0   /* not implemented */
200         HTTP_CREATED,
201         HTTP_ACCEPTED,
202         HTTP_NO_CONTENT,
203         HTTP_MULTIPLE_CHOICES,
204         HTTP_MOVED_PERMANENTLY,
205         HTTP_NOT_MODIFIED,
206         HTTP_BAD_GATEWAY,
207         HTTP_SERVICE_UNAVAILABLE,
208 #endif
209 };
210
211 static const struct {
212         const char *name;
213         const char *info;
214 } http_response[ARRAY_SIZE(http_response_type)] = {
215         { "OK", NULL },
216 #if ENABLE_FEATURE_HTTPD_RANGES
217         { "Partial Content", NULL },
218 #endif
219         { "Found", NULL },
220         { "Request Timeout", "No request appeared within 60 seconds" },
221         { "Not Implemented", "The requested method is not recognized" },
222 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
223         { "Unauthorized", "" },
224 #endif
225         { "Not Found", "The requested URL was not found" },
226         { "Bad Request", "Unsupported method" },
227         { "Forbidden", ""  },
228         { "Internal Server Error", "Internal Server Error" },
229 #if 0   /* not implemented */
230         { "Created" },
231         { "Accepted" },
232         { "No Content" },
233         { "Multiple Choices" },
234         { "Moved Permanently" },
235         { "Not Modified" },
236         { "Bad Gateway", "" },
237         { "Service Unavailable", "" },
238 #endif
239 };
240
241
242 struct globals {
243         int verbose;            /* must be int (used by getopt32) */
244         smallint flg_deny_all;
245
246         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
247         time_t last_mod;
248         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
249         const char *bind_addr_or_port;
250
251         const char *g_query;
252         const char *configFile;
253         const char *home_httpd;
254         const char *index_page;
255
256         const char *found_mime_type;
257         const char *found_moved_temporarily;
258         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
259
260         USE_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
261         USE_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
262         USE_FEATURE_HTTPD_CGI(char *referer;)
263         USE_FEATURE_HTTPD_CGI(char *user_agent;)
264
265         off_t file_size;        /* -1 - unknown */
266 #if ENABLE_FEATURE_HTTPD_RANGES
267         off_t range_start;
268         off_t range_end;
269         off_t range_len;
270 #endif
271
272 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
273         Htaccess *g_auth;       /* config user:password lines */
274 #endif
275 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
276         Htaccess *mime_a;       /* config mime types */
277 #endif
278 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
279         Htaccess *script_i;     /* config script interpreters */
280 #endif
281         char *iobuf;            /* [IOBUF_SIZE] */
282 #define hdr_buf bb_common_bufsiz1
283         char *hdr_ptr;
284         int hdr_cnt;
285 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
286         const char *http_error_page[ARRAY_SIZE(http_response_type)];
287 #endif
288 #if ENABLE_FEATURE_HTTPD_PROXY
289         Htaccess_Proxy *proxy;
290 #endif
291 };
292 #define G (*ptr_to_globals)
293 #define verbose           (G.verbose          )
294 #define flg_deny_all      (G.flg_deny_all     )
295 #define rmt_ip            (G.rmt_ip           )
296 #define bind_addr_or_port (G.bind_addr_or_port)
297 #define g_query           (G.g_query          )
298 #define configFile        (G.configFile       )
299 #define home_httpd        (G.home_httpd       )
300 #define index_page        (G.index_page       )
301 #define found_mime_type   (G.found_mime_type  )
302 #define found_moved_temporarily (G.found_moved_temporarily)
303 #define last_mod          (G.last_mod         )
304 #define ip_a_d            (G.ip_a_d           )
305 #define g_realm           (G.g_realm          )
306 #define remoteuser        (G.remoteuser       )
307 #define referer           (G.referer          )
308 #define user_agent        (G.user_agent       )
309 #define file_size         (G.file_size        )
310 #if ENABLE_FEATURE_HTTPD_RANGES
311 #define range_start       (G.range_start      )
312 #define range_end         (G.range_end        )
313 #define range_len         (G.range_len        )
314 #endif
315 #define rmt_ip_str        (G.rmt_ip_str       )
316 #define g_auth            (G.g_auth           )
317 #define mime_a            (G.mime_a           )
318 #define script_i          (G.script_i         )
319 #define iobuf             (G.iobuf            )
320 #define hdr_ptr           (G.hdr_ptr          )
321 #define hdr_cnt           (G.hdr_cnt          )
322 #define http_error_page   (G.http_error_page  )
323 #define proxy             (G.proxy            )
324 #define INIT_G() do { \
325         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
326         USE_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
327         bind_addr_or_port = "80"; \
328         index_page = "index.html"; \
329         file_size = -1; \
330 } while (0)
331
332 #if !ENABLE_FEATURE_HTTPD_RANGES
333 enum {
334         range_start = 0,
335         range_end = MAXINT(off_t) - 1,
336         range_len = MAXINT(off_t),
337 };
338 #endif
339
340
341 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
342
343 /* Prototypes */
344 enum {
345         SEND_HEADERS     = (1 << 0),
346         SEND_BODY        = (1 << 1),
347         SEND_HEADERS_AND_BODY = SEND_HEADERS + SEND_BODY,
348 };
349 static void send_file_and_exit(const char *url, int what) ATTRIBUTE_NORETURN;
350
351 static void free_llist(has_next_ptr **pptr)
352 {
353         has_next_ptr *cur = *pptr;
354         while (cur) {
355                 has_next_ptr *t = cur;
356                 cur = cur->next;
357                 free(t);
358         }
359         *pptr = NULL;
360 }
361
362 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
363  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
364  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
365 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
366 {
367         free_llist((has_next_ptr**)pptr);
368 }
369 #endif
370
371 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
372 {
373         free_llist((has_next_ptr**)pptr);
374 }
375
376 /* Returns presumed mask width in bits or < 0 on error.
377  * Updates strp, stores IP at provided pointer */
378 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
379 {
380         const char *p = *strp;
381         int auto_mask = 8;
382         unsigned ip = 0;
383         int j;
384
385         if (*p == '/')
386                 return -auto_mask;
387
388         for (j = 0; j < 4; j++) {
389                 unsigned octet;
390
391                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
392                         return -auto_mask;
393                 octet = 0;
394                 while (*p >= '0' && *p <= '9') {
395                         octet *= 10;
396                         octet += *p - '0';
397                         if (octet > 255)
398                                 return -auto_mask;
399                         p++;
400                 }
401                 if (*p == '.')
402                         p++;
403                 if (*p != '/' && *p)
404                         auto_mask += 8;
405                 ip = (ip << 8) | octet;
406         }
407         if (*p) {
408                 if (*p != endc)
409                         return -auto_mask;
410                 p++;
411                 if (*p == '\0')
412                         return -auto_mask;
413         }
414         *ipp = ip;
415         *strp = p;
416         return auto_mask;
417 }
418
419 /* Returns 0 on success. Stores IP and mask at provided pointers */
420 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
421 {
422         int i;
423         unsigned mask;
424         char *p;
425
426         i = scan_ip(&str, ipp, '/');
427         if (i < 0)
428                 return i;
429
430         if (*str) {
431                 /* there is /xxx after dotted-IP address */
432                 i = bb_strtou(str, &p, 10);
433                 if (*p == '.') {
434                         /* 'xxx' itself is dotted-IP mask, parse it */
435                         /* (return 0 (success) only if it has N.N.N.N form) */
436                         return scan_ip(&str, maskp, '\0') - 32;
437                 }
438                 if (*p)
439                         return -1;
440         }
441
442         if (i > 32)
443                 return -1;
444
445         if (sizeof(unsigned) == 4 && i == 32) {
446                 /* mask >>= 32 below may not work */
447                 mask = 0;
448         } else {
449                 mask = 0xffffffff;
450                 mask >>= i;
451         }
452         /* i == 0 -> *maskp = 0x00000000
453          * i == 1 -> *maskp = 0x80000000
454          * i == 4 -> *maskp = 0xf0000000
455          * i == 31 -> *maskp = 0xfffffffe
456          * i == 32 -> *maskp = 0xffffffff */
457         *maskp = (uint32_t)(~mask);
458         return 0;
459 }
460
461 /*
462  * Parse configuration file into in-memory linked list.
463  *
464  * The first non-white character is examined to determine if the config line
465  * is one of the following:
466  *    .ext:mime/type   # new mime type not compiled into httpd
467  *    [adAD]:from      # ip address allow/deny, * for wildcard
468  *    /path:user:pass  # username/password
469  *    Ennn:error.html  # error page for status nnn
470  *    P:/url:[http://]hostname[:port]/new/path # reverse proxy
471  *
472  * Any previous IP rules are discarded.
473  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
474  * are also discarded.  That is, previous settings are retained if flag is
475  * SUBDIR_PARSE.
476  * Error pages are only parsed on the main config file.
477  *
478  * path   Path where to look for httpd.conf (without filename).
479  * flag   Type of the parse request.
480  */
481 /* flag */
482 #define FIRST_PARSE          0
483 #define SUBDIR_PARSE         1
484 #define SIGNALED_PARSE       2
485 #define FIND_FROM_HTTPD_ROOT 3
486 static void parse_conf(const char *path, int flag)
487 {
488         FILE *f;
489 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
490         Htaccess *prev;
491 #endif
492 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
493  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
494  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
495         Htaccess *cur;
496 #endif
497         const char *cf = configFile;
498         char buf[160];
499         char *p0;
500         char *c, *p;
501         Htaccess_IP *pip;
502
503         /* discard old rules */
504         free_Htaccess_IP_list(&ip_a_d);
505         flg_deny_all = 0;
506 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
507  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
508  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
509         /* retain previous auth and mime config only for subdir parse */
510         if (flag != SUBDIR_PARSE) {
511 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
512                 free_Htaccess_list(&g_auth);
513 #endif
514 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
515                 free_Htaccess_list(&mime_a);
516 #endif
517 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
518                 free_Htaccess_list(&script_i);
519 #endif
520         }
521 #endif
522
523         if (flag == SUBDIR_PARSE || cf == NULL) {
524                 cf = alloca(strlen(path) + sizeof(httpd_conf) + 2);
525                 sprintf((char *)cf, "%s/%s", path, httpd_conf);
526         }
527
528         while ((f = fopen(cf, "r")) == NULL) {
529                 if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) {
530                         /* config file not found, no changes to config */
531                         return;
532                 }
533                 if (configFile && flag == FIRST_PARSE) /* if -c option given */
534                         bb_simple_perror_msg_and_die(cf);
535                 flag = FIND_FROM_HTTPD_ROOT;
536                 cf = httpd_conf;
537         }
538
539 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
540         prev = g_auth;
541 #endif
542         /* This could stand some work */
543         while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) {
544                 c = NULL;
545                 for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) {
546                         if (!isspace(*p0)) {
547                                 *p++ = *p0;
548                                 if (*p0 == ':' && c == NULL)
549                                         c = p;
550                         }
551                 }
552                 *p = '\0';
553
554                 /* test for empty or strange line */
555                 if (c == NULL || *c == '\0')
556                         continue;
557                 p0 = buf;
558                 if (*p0 == 'd')
559                         *p0 = 'D';
560                 if (*c == '*') {
561                         if (*p0 == 'D') {
562                                 /* memorize deny all */
563                                 flg_deny_all = 1;
564                         }
565                         /* skip default other "word:*" config lines */
566                         continue;
567                 }
568
569                 if (*p0 == 'a')
570                         *p0 = 'A';
571                 if (*p0 == 'A' || *p0 == 'D') {
572                         /* storing current config IP line */
573                         pip = xzalloc(sizeof(Htaccess_IP));
574                         if (pip) {
575                                 if (scan_ip_mask(c, &(pip->ip), &(pip->mask))) {
576                                         /* syntax IP{/mask} error detected, protect all */
577                                         *p0 = 'D';
578                                         pip->mask = 0;
579                                 }
580                                 pip->allow_deny = *p0;
581                                 if (*p0 == 'D') {
582                                         /* Deny:from_IP move top */
583                                         pip->next = ip_a_d;
584                                         ip_a_d = pip;
585                                 } else {
586                                         /* add to bottom A:form_IP config line */
587                                         Htaccess_IP *prev_IP = ip_a_d;
588
589                                         if (prev_IP == NULL) {
590                                                 ip_a_d = pip;
591                                         } else {
592                                                 while (prev_IP->next)
593                                                         prev_IP = prev_IP->next;
594                                                 prev_IP->next = pip;
595                                         }
596                                 }
597                         }
598                         continue;
599                 }
600
601 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
602                 if (flag == FIRST_PARSE && *p0 == 'E') {
603                         int i;
604                         /* error status code */
605                         int status = atoi(++p0);
606                         /* c already points at the character following ':' in parse loop */
607                         /* c = strchr(p0, ':'); c++; */
608                         if (status < HTTP_CONTINUE) {
609                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
610                                 continue;
611                         }
612
613                         /* then error page; find matching status */
614                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
615                                 if (http_response_type[i] == status) {
616                                         http_error_page[i] = concat_path_file((*c == '/') ? NULL : home_httpd, c);
617                                         break;
618                                 }
619                         }
620                         continue;
621                 }
622 #endif
623
624 #if ENABLE_FEATURE_HTTPD_PROXY
625                 if (flag == FIRST_PARSE && *p0 == 'P') {
626                         /* P:/url:[http://]hostname[:port]/new/path */
627                         char *url_from, *host_port, *url_to;
628                         Htaccess_Proxy *proxy_entry;
629
630                         url_from = c;
631                         host_port = strchr(c, ':');
632                         if (host_port == NULL) {
633                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
634                                 continue;
635                         }
636                         *host_port++ = '\0';
637                         if (strncmp(host_port, "http://", 7) == 0)
638                                 host_port += 7;
639                         if (*host_port == '\0') {
640                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
641                                 continue;
642                         }
643                         url_to = strchr(host_port, '/');
644                         if (url_to == NULL) {
645                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
646                                 continue;
647                         }
648                         *url_to = '\0';
649                         proxy_entry = xzalloc(sizeof(Htaccess_Proxy));
650                         proxy_entry->url_from = xstrdup(url_from);
651                         proxy_entry->host_port = xstrdup(host_port);
652                         *url_to = '/';
653                         proxy_entry->url_to = xstrdup(url_to);
654                         proxy_entry->next = proxy;
655                         proxy = proxy_entry;
656                         continue;
657                 }
658 #endif
659
660 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
661                 if (*p0 == '/') {
662                         /* make full path from httpd root / current_path / config_line_path */
663                         cf = (flag == SUBDIR_PARSE ? path : "");
664                         p0 = xmalloc(strlen(cf) + (c - buf) + 2 + strlen(c));
665                         c[-1] = '\0';
666                         sprintf(p0, "/%s%s", cf, buf);
667
668                         /* another call bb_simplify_path */
669                         cf = p = p0;
670
671                         do {
672                                 if (*p == '/') {
673                                         if (*cf == '/') {    /* skip duplicate (or initial) slash */
674                                                 continue;
675                                         }
676                                         if (*cf == '.') {
677                                                 if (cf[1] == '/' || cf[1] == '\0') { /* remove extra '.' */
678                                                         continue;
679                                                 }
680                                                 if ((cf[1] == '.') && (cf[2] == '/' || cf[2] == '\0')) {
681                                                         ++cf;
682                                                         if (p > p0) {
683                                                                 while (*--p != '/') /* omit previous dir */;
684                                                         }
685                                                         continue;
686                                                 }
687                                         }
688                                 }
689                                 *++p = *cf;
690                         } while (*++cf);
691
692                         if ((p == p0) || (*p != '/')) {      /* not a trailing slash */
693                                 ++p;                             /* so keep last character */
694                         }
695                         *p = ':';
696                         strcpy(p + 1, c);
697                 }
698 #endif
699
700                 if (*p0 == 'I') {
701                         index_page = xstrdup(c);
702                         continue;
703                 }
704
705 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
706  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
707  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
708                 /* storing current config line */
709                 cur = xzalloc(sizeof(Htaccess) + strlen(p0));
710                 cf = strcpy(cur->before_colon, p0);
711 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
712                 if (*p0 == '/')
713                         free(p0);
714 #endif
715                 c = strchr(cf, ':');
716                 *c++ = '\0';
717                 cur->after_colon = c;
718 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
719                 if (*cf == '.') {
720                         /* config .mime line move top for overwrite previous */
721                         cur->next = mime_a;
722                         mime_a = cur;
723                         continue;
724                 }
725 #endif
726 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
727                 if (*cf == '*' && cf[1] == '.') {
728                         /* config script interpreter line move top for overwrite previous */
729                         cur->next = script_i;
730                         script_i = cur;
731                         continue;
732                 }
733 #endif
734 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
735                 if (prev == NULL) {
736                         /* first line */
737                         g_auth = prev = cur;
738                 } else {
739                         /* sort path, if current length eq or bigger then move up */
740                         Htaccess *prev_hti = g_auth;
741                         size_t l = strlen(cf);
742                         Htaccess *hti;
743
744                         for (hti = prev_hti; hti; hti = hti->next) {
745                                 if (l >= strlen(hti->before_colon)) {
746                                         /* insert before hti */
747                                         cur->next = hti;
748                                         if (prev_hti != hti) {
749                                                 prev_hti->next = cur;
750                                         } else {
751                                                 /* insert as top */
752                                                 g_auth = cur;
753                                         }
754                                         break;
755                                 }
756                                 if (prev_hti != hti)
757                                         prev_hti = prev_hti->next;
758                         }
759                         if (!hti) {       /* not inserted, add to bottom */
760                                 prev->next = cur;
761                                 prev = cur;
762                         }
763                 }
764 #endif /* BASIC_AUTH */
765 #endif /* BASIC_AUTH || MIME_TYPES || SCRIPT_INTERPR */
766          } /* while (fgets) */
767          fclose(f);
768 }
769
770 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
771 /*
772  * Given a string, html-encode special characters.
773  * This is used for the -e command line option to provide an easy way
774  * for scripts to encode result data without confusing browsers.  The
775  * returned string pointer is memory allocated by malloc().
776  *
777  * Returns a pointer to the encoded string (malloced).
778  */
779 static char *encodeString(const char *string)
780 {
781         /* take the simple route and encode everything */
782         /* could possibly scan once to get length.     */
783         int len = strlen(string);
784         char *out = xmalloc(len * 6 + 1);
785         char *p = out;
786         char ch;
787
788         while ((ch = *string++)) {
789                 /* very simple check for what to encode */
790                 if (isalnum(ch))
791                         *p++ = ch;
792                 else
793                         p += sprintf(p, "&#%d;", (unsigned char) ch);
794         }
795         *p = '\0';
796         return out;
797 }
798 #endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
799
800 /*
801  * Given a URL encoded string, convert it to plain ascii.
802  * Since decoding always makes strings smaller, the decode is done in-place.
803  * Thus, callers should strdup() the argument if they do not want the
804  * argument modified.  The return is the original pointer, allowing this
805  * function to be easily used as arguments to other functions.
806  *
807  * string    The first string to decode.
808  * option_d  1 if called for httpd -d
809  *
810  * Returns a pointer to the decoded string (same as input).
811  */
812 static unsigned hex_to_bin(unsigned char c)
813 {
814         unsigned v;
815
816         v = c - '0';
817         if (v <= 9)
818                 return v;
819         /* c | 0x20: letters to lower case, non-letters
820          * to (potentially different) non-letters */
821         v = (unsigned)(c | 0x20) - 'a';
822         if (v <= 5)
823                 return v + 10;
824         return ~0;
825 }
826 /* For testing:
827 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
828 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
829 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
830 */
831 static char *decodeString(char *orig, int option_d)
832 {
833         /* note that decoded string is always shorter than original */
834         char *string = orig;
835         char *ptr = string;
836         char c;
837
838         while ((c = *ptr++) != '\0') {
839                 unsigned v;
840
841                 if (option_d && c == '+') {
842                         *string++ = ' ';
843                         continue;
844                 }
845                 if (c != '%') {
846                         *string++ = c;
847                         continue;
848                 }
849                 v = hex_to_bin(ptr[0]);
850                 if (v > 15) {
851  bad_hex:
852                         if (!option_d)
853                                 return NULL;
854                         *string++ = '%';
855                         continue;
856                 }
857                 v = (v * 16) | hex_to_bin(ptr[1]);
858                 if (v > 255)
859                         goto bad_hex;
860                 if (!option_d && (v == '/' || v == '\0')) {
861                         /* caller takes it as indication of invalid
862                          * (dangerous wrt exploits) chars */
863                         return orig + 1;
864                 }
865                 *string++ = v;
866                 ptr += 2;
867         }
868         *string = '\0';
869         return orig;
870 }
871
872 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
873 /*
874  * Decode a base64 data stream as per rfc1521.
875  * Note that the rfc states that non base64 chars are to be ignored.
876  * Since the decode always results in a shorter size than the input,
877  * it is OK to pass the input arg as an output arg.
878  * Parameter: a pointer to a base64 encoded string.
879  * Decoded data is stored in-place.
880  */
881 static void decodeBase64(char *Data)
882 {
883         const unsigned char *in = (const unsigned char *)Data;
884         /* The decoded size will be at most 3/4 the size of the encoded */
885         unsigned ch = 0;
886         int i = 0;
887
888         while (*in) {
889                 int t = *in++;
890
891                 if (t >= '0' && t <= '9')
892                         t = t - '0' + 52;
893                 else if (t >= 'A' && t <= 'Z')
894                         t = t - 'A';
895                 else if (t >= 'a' && t <= 'z')
896                         t = t - 'a' + 26;
897                 else if (t == '+')
898                         t = 62;
899                 else if (t == '/')
900                         t = 63;
901                 else if (t == '=')
902                         t = 0;
903                 else
904                         continue;
905
906                 ch = (ch << 6) | t;
907                 i++;
908                 if (i == 4) {
909                         *Data++ = (char) (ch >> 16);
910                         *Data++ = (char) (ch >> 8);
911                         *Data++ = (char) ch;
912                         i = 0;
913                 }
914         }
915         *Data = '\0';
916 }
917 #endif
918
919 /*
920  * Create a listen server socket on the designated port.
921  */
922 static int openServer(void)
923 {
924         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
925         if (!errno && n && n <= 0xffff)
926                 n = create_and_bind_stream_or_die(NULL, n);
927         else
928                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
929         xlisten(n, 9);
930         return n;
931 }
932
933 /*
934  * Log the connection closure and exit.
935  */
936 static void log_and_exit(void) ATTRIBUTE_NORETURN;
937 static void log_and_exit(void)
938 {
939         /* Paranoia. IE said to be buggy. It may send some extra data
940          * or be confused by us just exiting without SHUT_WR. Oh well. */
941         shutdown(1, SHUT_WR);
942         ndelay_on(0);
943         while (read(0, iobuf, IOBUF_SIZE) > 0)
944                 continue;
945
946         if (verbose > 2)
947                 bb_error_msg("closed");
948         _exit(xfunc_error_retval);
949 }
950
951 /*
952  * Create and send HTTP response headers.
953  * The arguments are combined and sent as one write operation.  Note that
954  * IE will puke big-time if the headers are not sent in one packet and the
955  * second packet is delayed for any reason.
956  * responseNum - the result code to send.
957  */
958 static void send_headers(int responseNum)
959 {
960         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
961
962         const char *responseString = "";
963         const char *infoString = NULL;
964         const char *mime_type;
965 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
966         const char *error_page = NULL;
967 #endif
968         unsigned i;
969         time_t timer = time(0);
970         char tmp_str[80];
971         int len;
972
973         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
974                 if (http_response_type[i] == responseNum) {
975                         responseString = http_response[i].name;
976                         infoString = http_response[i].info;
977 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
978                         error_page = http_error_page[i];
979 #endif
980                         break;
981                 }
982         }
983         /* error message is HTML */
984         mime_type = responseNum == HTTP_OK ?
985                                 found_mime_type : "text/html";
986
987         if (verbose)
988                 bb_error_msg("response:%u", responseNum);
989
990         /* emit the current date */
991         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
992         len = sprintf(iobuf,
993                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
994                         "Date: %s\r\nConnection: close\r\n",
995                         responseNum, responseString, mime_type, tmp_str);
996
997 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
998         if (responseNum == HTTP_UNAUTHORIZED) {
999                 len += sprintf(iobuf + len,
1000                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
1001                                 g_realm);
1002         }
1003 #endif
1004         if (responseNum == HTTP_MOVED_TEMPORARILY) {
1005                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
1006                                 found_moved_temporarily,
1007                                 (g_query ? "?" : ""),
1008                                 (g_query ? g_query : ""));
1009         }
1010
1011 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
1012         if (error_page && !access(error_page, R_OK)) {
1013                 strcat(iobuf, "\r\n");
1014                 len += 2;
1015
1016                 if (DEBUG)
1017                         fprintf(stderr, "headers: '%s'\n", iobuf);
1018                 full_write(1, iobuf, len);
1019                 if (DEBUG)
1020                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1021                 return send_file_and_exit(error_page, SEND_BODY);
1022         }
1023 #endif
1024
1025         if (file_size != -1) {    /* file */
1026                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1027 #if ENABLE_FEATURE_HTTPD_RANGES
1028                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1029                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"d-%"OFF_FMT"d/%"OFF_FMT"d\r\n",
1030                                         range_start,
1031                                         range_end,
1032                                         file_size);
1033                         file_size = range_end - range_start + 1;
1034                 }
1035 #endif
1036                 len += sprintf(iobuf + len,
1037 #if ENABLE_FEATURE_HTTPD_RANGES
1038                         "Accept-Ranges: bytes\r\n"
1039 #endif
1040                         "Last-Modified: %s\r\n%s %"OFF_FMT"d\r\n",
1041                                 tmp_str,
1042                                 "Content-length:",
1043                                 file_size
1044                 );
1045         }
1046         iobuf[len++] = '\r';
1047         iobuf[len++] = '\n';
1048         if (infoString) {
1049                 len += sprintf(iobuf + len,
1050                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1051                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1052                                 responseNum, responseString,
1053                                 responseNum, responseString, infoString);
1054         }
1055         if (DEBUG)
1056                 fprintf(stderr, "headers: '%s'\n", iobuf);
1057         if (full_write(1, iobuf, len) != len) {
1058                 if (verbose > 1)
1059                         bb_perror_msg("error");
1060                 log_and_exit();
1061         }
1062 }
1063
1064 static void send_headers_and_exit(int responseNum) ATTRIBUTE_NORETURN;
1065 static void send_headers_and_exit(int responseNum)
1066 {
1067         send_headers(responseNum);
1068         log_and_exit();
1069 }
1070
1071 /*
1072  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1073  * '\n' is replaced with NUL.
1074  * Return number of characters read or 0 if nothing is read
1075  * ('\r' and '\n' are not counted).
1076  * Data is returned in iobuf.
1077  */
1078 static int get_line(void)
1079 {
1080         int count = 0;
1081         char c;
1082
1083         while (1) {
1084                 if (hdr_cnt <= 0) {
1085                         hdr_cnt = safe_read(0, hdr_buf, sizeof(hdr_buf));
1086                         if (hdr_cnt <= 0)
1087                                 break;
1088                         hdr_ptr = hdr_buf;
1089                 }
1090                 iobuf[count] = c = *hdr_ptr++;
1091                 hdr_cnt--;
1092
1093                 if (c == '\r')
1094                         continue;
1095                 if (c == '\n') {
1096                         iobuf[count] = '\0';
1097                         return count;
1098                 }
1099                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1100                         count++;
1101         }
1102         return count;
1103 }
1104
1105 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1106
1107 /* gcc 4.2.1 fares better with NOINLINE */
1108 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) ATTRIBUTE_NORETURN;
1109 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1110 {
1111         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1112         struct pollfd pfd[3];
1113         int out_cnt; /* we buffer a bit of initial CGI output */
1114         int count;
1115
1116         /* iobuf is used for CGI -> network data,
1117          * hdr_buf is for network -> CGI data (POSTDATA) */
1118
1119         /* If CGI dies, we still want to correctly finish reading its output
1120          * and send it to the peer. So please no SIGPIPEs! */
1121         signal(SIGPIPE, SIG_IGN);
1122
1123         // We inconsistently handle a case when more POSTDATA from network
1124         // is coming than we expected. We may give *some part* of that
1125         // extra data to CGI.
1126
1127         //if (hdr_cnt > post_len) {
1128         //      /* We got more POSTDATA from network than we expected */
1129         //      hdr_cnt = post_len;
1130         //}
1131         post_len -= hdr_cnt;
1132         /* post_len - number of POST bytes not yet read from network */
1133
1134         /* NB: breaking out of this loop jumps to log_and_exit() */
1135         out_cnt = 0;
1136         while (1) {
1137                 memset(pfd, 0, sizeof(pfd));
1138
1139                 pfd[FROM_CGI].fd = fromCgi_rd;
1140                 pfd[FROM_CGI].events = POLLIN;
1141
1142                 if (toCgi_wr) {
1143                         pfd[TO_CGI].fd = toCgi_wr;
1144                         if (hdr_cnt > 0) {
1145                                 pfd[TO_CGI].events = POLLOUT;
1146                         } else if (post_len > 0) {
1147                                 pfd[0].events = POLLIN;
1148                         } else {
1149                                 /* post_len <= 0 && hdr_cnt <= 0:
1150                                  * no more POST data to CGI,
1151                                  * let CGI see EOF on CGI's stdin */
1152                                 close(toCgi_wr);
1153                                 toCgi_wr = 0;
1154                         }
1155                 }
1156
1157                 /* Now wait on the set of sockets */
1158                 count = safe_poll(pfd, 3, -1);
1159                 if (count <= 0) {
1160 #if 0
1161                         if (safe_waitpid(pid, &status, WNOHANG) <= 0) {
1162                                 /* Weird. CGI didn't exit and no fd's
1163                                  * are ready, yet poll returned?! */
1164                                 continue;
1165                         }
1166                         if (DEBUG && WIFEXITED(status))
1167                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1168                         if (DEBUG && WIFSIGNALED(status))
1169                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1170 #endif
1171                         break;
1172                 }
1173
1174                 if (pfd[TO_CGI].revents) {
1175                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1176                         /* Have data from peer and can write to CGI */
1177                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1178                         /* Doesn't happen, we dont use nonblocking IO here
1179                          *if (count < 0 && errno == EAGAIN) {
1180                          *      ...
1181                          *} else */
1182                         if (count > 0) {
1183                                 hdr_ptr += count;
1184                                 hdr_cnt -= count;
1185                         } else {
1186                                 /* EOF/broken pipe to CGI, stop piping POST data */
1187                                 hdr_cnt = post_len = 0;
1188                         }
1189                 }
1190
1191                 if (pfd[0].revents) {
1192                         /* post_len > 0 && hdr_cnt == 0 here */
1193                         /* We expect data, prev data portion is eaten by CGI
1194                          * and there *is* data to read from the peer
1195                          * (POSTDATA) */
1196                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1197                         //count = safe_read(0, hdr_buf, count);
1198                         count = safe_read(0, hdr_buf, sizeof(hdr_buf));
1199                         if (count > 0) {
1200                                 hdr_cnt = count;
1201                                 hdr_ptr = hdr_buf;
1202                                 post_len -= count;
1203                         } else {
1204                                 /* no more POST data can be read */
1205                                 post_len = 0;
1206                         }
1207                 }
1208
1209                 if (pfd[FROM_CGI].revents) {
1210                         /* There is something to read from CGI */
1211                         char *rbuf = iobuf;
1212
1213                         /* Are we still buffering CGI output? */
1214                         if (out_cnt >= 0) {
1215                                 /* HTTP_200[] has single "\r\n" at the end.
1216                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1217                                  * CGI scripts MUST send their own header terminated by
1218                                  * empty line, then data. That's why we have only one
1219                                  * <cr><lf> pair here. We will output "200 OK" line
1220                                  * if needed, but CGI still has to provide blank line
1221                                  * between header and body */
1222
1223                                 /* Must use safe_read, not full_read, because
1224                                  * CGI may output a few first bytes and then wait
1225                                  * for POSTDATA without closing stdout.
1226                                  * With full_read we may wait here forever. */
1227                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1228                                 if (count <= 0) {
1229                                         /* eof (or error) and there was no "HTTP",
1230                                          * so write it, then write received data */
1231                                         if (out_cnt) {
1232                                                 full_write(1, HTTP_200, sizeof(HTTP_200)-1);
1233                                                 full_write(1, rbuf, out_cnt);
1234                                         }
1235                                         break; /* CGI stdout is closed, exiting */
1236                                 }
1237                                 out_cnt += count;
1238                                 count = 0;
1239                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1240                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1241                                         /* send "HTTP/1.0 " */
1242                                         if (full_write(1, HTTP_200, 9) != 9)
1243                                                 break;
1244                                         rbuf += 8; /* skip "Status: " */
1245                                         count = out_cnt - 8;
1246                                         out_cnt = -1; /* buffering off */
1247                                 } else if (out_cnt >= 4) {
1248                                         /* Did CGI add "HTTP"? */
1249                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1250                                                 /* there is no "HTTP", do it ourself */
1251                                                 if (full_write(1, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1252                                                         break;
1253                                         }
1254                                         /* Commented out:
1255                                         if (!strstr(rbuf, "ontent-")) {
1256                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1257                                         }
1258                                          * Counter-example of valid CGI without Content-type:
1259                                          * echo -en "HTTP/1.0 302 Found\r\n"
1260                                          * echo -en "Location: http://www.busybox.net\r\n"
1261                                          * echo -en "\r\n"
1262                                          */
1263                                         count = out_cnt;
1264                                         out_cnt = -1; /* buffering off */
1265                                 }
1266                         } else {
1267                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1268                                 if (count <= 0)
1269                                         break;  /* eof (or error) */
1270                         }
1271                         if (full_write(1, rbuf, count) != count)
1272                                 break;
1273                         if (DEBUG)
1274                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1275                 } /* if (pfd[FROM_CGI].revents) */
1276         } /* while (1) */
1277         log_and_exit();
1278 }
1279 #endif
1280
1281 #if ENABLE_FEATURE_HTTPD_CGI
1282
1283 static void setenv1(const char *name, const char *value)
1284 {
1285         setenv(name, value ? value : "", 1);
1286 }
1287
1288 /*
1289  * Spawn CGI script, forward CGI's stdin/out <=> network
1290  *
1291  * Environment variables are set up and the script is invoked with pipes
1292  * for stdin/stdout.  If a POST is being done the script is fed the POST
1293  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1294  *
1295  * Parameters:
1296  * const char *url              The requested URL (with leading /).
1297  * int post_len                 Length of the POST body.
1298  * const char *cookie           For set HTTP_COOKIE.
1299  * const char *content_type     For set CONTENT_TYPE.
1300  */
1301 static void send_cgi_and_exit(
1302                 const char *url,
1303                 const char *request,
1304                 int post_len,
1305                 const char *cookie,
1306                 const char *content_type) ATTRIBUTE_NORETURN;
1307 static void send_cgi_and_exit(
1308                 const char *url,
1309                 const char *request,
1310                 int post_len,
1311                 const char *cookie,
1312                 const char *content_type)
1313 {
1314         struct fd_pair fromCgi;  /* CGI -> httpd pipe */
1315         struct fd_pair toCgi;    /* httpd -> CGI pipe */
1316         char *fullpath;
1317         char *script;
1318         char *purl;
1319         int pid;
1320
1321         /*
1322          * We are mucking with environment _first_ and then vfork/exec,
1323          * this allows us to use vfork safely. Parent don't care about
1324          * these environment changes anyway.
1325          */
1326
1327         /*
1328          * Find PATH_INFO.
1329          */
1330         purl = xstrdup(url);
1331         script = purl;
1332         while ((script = strchr(script + 1, '/')) != NULL) {
1333                 /* have script.cgi/PATH_INFO or dirs/script.cgi[/PATH_INFO] */
1334                 struct stat sb;
1335
1336                 *script = '\0';
1337                 if (!is_directory(purl + 1, 1, &sb)) {
1338                         /* not directory, found script.cgi/PATH_INFO */
1339                         *script = '/';
1340                         break;
1341                 }
1342                 *script = '/';          /* is directory, find next '/' */
1343         }
1344         setenv1("PATH_INFO", script);   /* set /PATH_INFO or "" */
1345         setenv1("REQUEST_METHOD", request);
1346         if (g_query) {
1347                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", purl, g_query));
1348         } else {
1349                 setenv1("REQUEST_URI", purl);
1350         }
1351         if (script != NULL)
1352                 *script = '\0';         /* cut off /PATH_INFO */
1353
1354         /* SCRIPT_FILENAME required by PHP in CGI mode */
1355         fullpath = concat_path_file(home_httpd, purl);
1356         setenv1("SCRIPT_FILENAME", fullpath);
1357         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1358         setenv1("SCRIPT_NAME", purl);
1359         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1360          * QUERY_STRING: The information which follows the ? in the URL
1361          * which referenced this script. This is the query information.
1362          * It should not be decoded in any fashion. This variable
1363          * should always be set when there is query information,
1364          * regardless of command line decoding. */
1365         /* (Older versions of bbox seem to do some decoding) */
1366         setenv1("QUERY_STRING", g_query);
1367         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1368         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1369         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1370         /* Having _separate_ variables for IP and port defeats
1371          * the purpose of having socket abstraction. Which "port"
1372          * are you using on Unix domain socket?
1373          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1374          * Oh well... */
1375         {
1376                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1377                 char *cp = strrchr(p, ':');
1378                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1379                         cp = NULL;
1380                 if (cp) *cp = '\0'; /* delete :PORT */
1381                 setenv1("REMOTE_ADDR", p);
1382                 if (cp) {
1383                         *cp = ':';
1384 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1385                         setenv1("REMOTE_PORT", cp + 1);
1386 #endif
1387                 }
1388         }
1389         setenv1("HTTP_USER_AGENT", user_agent);
1390         if (post_len)
1391                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1392         if (cookie)
1393                 setenv1("HTTP_COOKIE", cookie);
1394         if (content_type)
1395                 setenv1("CONTENT_TYPE", content_type);
1396 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1397         if (remoteuser) {
1398                 setenv1("REMOTE_USER", remoteuser);
1399                 putenv((char*)"AUTH_TYPE=Basic");
1400         }
1401 #endif
1402         if (referer)
1403                 setenv1("HTTP_REFERER", referer);
1404
1405         xpiped_pair(fromCgi);
1406         xpiped_pair(toCgi);
1407
1408         pid = vfork();
1409         if (pid < 0) {
1410                 /* TODO: log perror? */
1411                 log_and_exit();
1412         }
1413
1414         if (!pid) {
1415                 /* Child process */
1416                 xfunc_error_retval = 242;
1417
1418                 /* NB: close _first_, then move fds! */
1419                 close(toCgi.wr);
1420                 close(fromCgi.rd);
1421                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1422                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1423                 /* User seeing stderr output can be a security problem.
1424                  * If CGI really wants that, it can always do dup itself. */
1425                 /* dup2(1, 2); */
1426
1427                 script = strrchr(fullpath, '/');
1428                 //fullpath is a result of concat_path_file and always has '/'
1429                 //if (!script)
1430                 //      goto error_execing_cgi;
1431                 *script = '\0';
1432                 /* chdiring to script's dir */
1433                 if (chdir(script == fullpath ? "/" : fullpath) == 0) {
1434                         char *argv[3];
1435
1436                         *script++ = '/'; /* repair fullpath */
1437                         /* set argv[0] to name without path */
1438                         argv[0] = script;
1439                         argv[1] = NULL;
1440
1441 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1442                         {
1443                                 char *suffix = strrchr(script, '.');
1444
1445                                 if (suffix) {
1446                                         Htaccess *cur;
1447                                         for (cur = script_i; cur; cur = cur->next) {
1448                                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
1449                                                         /* found interpreter name */
1450                                                         fullpath = cur->after_colon;
1451                                                         argv[0] = cur->after_colon;
1452                                                         argv[1] = script;
1453                                                         argv[2] = NULL;
1454                                                         break;
1455                                                 }
1456                                         }
1457                                 }
1458                         }
1459 #endif
1460                         /* restore default signal dispositions for CGI process */
1461                         signal(SIGCHLD, SIG_DFL);
1462                         signal(SIGPIPE, SIG_DFL);
1463                         signal(SIGHUP, SIG_DFL);
1464
1465                         execv(fullpath, argv);
1466                         if (verbose)
1467                                 bb_perror_msg("exec %s", fullpath);
1468                 } else if (verbose) {
1469                         bb_perror_msg("chdir %s", fullpath);
1470                 }
1471  //error_execing_cgi:
1472                 /* send to stdout
1473                  * (we are CGI here, our stdout is pumped to the net) */
1474                 send_headers_and_exit(HTTP_NOT_FOUND);
1475         } /* end child */
1476
1477         /* Parent process */
1478
1479         /* Restore variables possibly changed by child */
1480         xfunc_error_retval = 0;
1481
1482         /* Pump data */
1483         close(fromCgi.wr);
1484         close(toCgi.rd);
1485         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1486 }
1487
1488 #endif          /* FEATURE_HTTPD_CGI */
1489
1490 /*
1491  * Send a file response to a HTTP request, and exit
1492  *
1493  * Parameters:
1494  * const char *url  The requested URL (with leading /).
1495  * what             What to send (headers/body/both).
1496  */
1497 static void send_file_and_exit(const char *url, int what)
1498 {
1499         static const char *const suffixTable[] = {
1500         /* Warning: shorter equivalent suffix in one line must be first */
1501                 ".htm.html", "text/html",
1502                 ".jpg.jpeg", "image/jpeg",
1503                 ".gif",      "image/gif",
1504                 ".png",      "image/png",
1505                 ".txt.h.c.cc.cpp", "text/plain",
1506                 ".css",      "text/css",
1507                 ".wav",      "audio/wav",
1508                 ".avi",      "video/x-msvideo",
1509                 ".qt.mov",   "video/quicktime",
1510                 ".mpe.mpeg", "video/mpeg",
1511                 ".mid.midi", "audio/midi",
1512                 ".mp3",      "audio/mpeg",
1513 #if 0                        /* unpopular */
1514                 ".au",       "audio/basic",
1515                 ".pac",      "application/x-ns-proxy-autoconfig",
1516                 ".vrml.wrl", "model/vrml",
1517 #endif
1518                 NULL
1519         };
1520
1521         char *suffix;
1522         int f;
1523         const char *const *table;
1524         const char *try_suffix;
1525         ssize_t count;
1526 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1527         off_t offset;
1528 #endif
1529
1530         /* If you want to know about EPIPE below
1531          * (happens if you abort downloads from local httpd): */
1532         signal(SIGPIPE, SIG_IGN);
1533
1534         suffix = strrchr(url, '.');
1535
1536         /* If not found, set default as "application/octet-stream";  */
1537         found_mime_type = "application/octet-stream";
1538         if (suffix) {
1539 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1540                 Htaccess *cur;
1541 #endif
1542                 for (table = suffixTable; *table; table += 2) {
1543                         try_suffix = strstr(table[0], suffix);
1544                         if (try_suffix) {
1545                                 try_suffix += strlen(suffix);
1546                                 if (*try_suffix == '\0' || *try_suffix == '.') {
1547                                         found_mime_type = table[1];
1548                                         break;
1549                                 }
1550                         }
1551                 }
1552 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1553                 for (cur = mime_a; cur; cur = cur->next) {
1554                         if (strcmp(cur->before_colon, suffix) == 0) {
1555                                 found_mime_type = cur->after_colon;
1556                                 break;
1557                         }
1558                 }
1559 #endif
1560         }
1561
1562         if (DEBUG)
1563                 bb_error_msg("sending file '%s' content-type: %s",
1564                         url, found_mime_type);
1565
1566         f = open(url, O_RDONLY);
1567         if (f < 0) {
1568                 if (DEBUG)
1569                         bb_perror_msg("cannot open '%s'", url);
1570                 /* Error pages are sent by using send_file_and_exit(SEND_BODY).
1571                  * IOW: it is unsafe to call send_headers_and_exit
1572                  * if what is SEND_BODY! Can recurse! */
1573                 if (what != SEND_BODY)
1574                         send_headers_and_exit(HTTP_NOT_FOUND);
1575                 log_and_exit();
1576         }
1577 #if ENABLE_FEATURE_HTTPD_RANGES
1578         if (what == SEND_BODY)
1579                 range_start = 0; /* err pages and ranges don't mix */
1580         range_len = MAXINT(off_t);
1581         if (range_start) {
1582                 if (!range_end) {
1583                         range_end = file_size - 1;
1584                 }
1585                 if (range_end < range_start
1586                  || lseek(f, range_start, SEEK_SET) != range_start
1587                 ) {
1588                         lseek(f, 0, SEEK_SET);
1589                         range_start = 0;
1590                 } else {
1591                         range_len = range_end - range_start + 1;
1592                         send_headers(HTTP_PARTIAL_CONTENT);
1593                         what = SEND_BODY;
1594                 }
1595         }
1596 #endif
1597
1598         if (what & SEND_HEADERS)
1599                 send_headers(HTTP_OK);
1600
1601 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1602         offset = range_start;
1603         do {
1604                 /* sz is rounded down to 64k */
1605                 ssize_t sz = MAXINT(ssize_t) - 0xffff;
1606                 USE_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1607                 count = sendfile(1, f, &offset, sz);
1608                 if (count < 0) {
1609                         if (offset == range_start)
1610                                 goto fallback;
1611                         goto fin;
1612                 }
1613                 USE_FEATURE_HTTPD_RANGES(range_len -= sz;)
1614         } while (count > 0 && range_len);
1615         log_and_exit();
1616
1617  fallback:
1618 #endif
1619         while ((count = safe_read(f, iobuf, IOBUF_SIZE)) > 0) {
1620                 ssize_t n;
1621                 USE_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1622                 n = full_write(1, iobuf, count);
1623                 if (count != n)
1624                         break;
1625                 USE_FEATURE_HTTPD_RANGES(range_len -= count;)
1626                 if (!range_len)
1627                         break;
1628         }
1629 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1630  fin:
1631 #endif
1632         if (count < 0 && verbose > 1)
1633                 bb_perror_msg("error");
1634         log_and_exit();
1635 }
1636
1637 static int checkPermIP(void)
1638 {
1639         Htaccess_IP *cur;
1640
1641         /* This could stand some work */
1642         for (cur = ip_a_d; cur; cur = cur->next) {
1643 #if DEBUG
1644                 fprintf(stderr,
1645                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1646                         rmt_ip_str,
1647                         (unsigned char)(cur->ip >> 24),
1648                         (unsigned char)(cur->ip >> 16),
1649                         (unsigned char)(cur->ip >> 8),
1650                         (unsigned char)(cur->ip),
1651                         (unsigned char)(cur->mask >> 24),
1652                         (unsigned char)(cur->mask >> 16),
1653                         (unsigned char)(cur->mask >> 8),
1654                         (unsigned char)(cur->mask)
1655                 );
1656 #endif
1657                 if ((rmt_ip & cur->mask) == cur->ip)
1658                         return cur->allow_deny == 'A';   /* Allow/Deny */
1659         }
1660
1661         /* if unconfigured, return 1 - access from all */
1662         return !flg_deny_all;
1663 }
1664
1665 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1666 /*
1667  * Check the permission file for access password protected.
1668  *
1669  * If config file isn't present, everything is allowed.
1670  * Entries are of the form you can see example from header source
1671  *
1672  * path      The file path.
1673  * request   User information to validate.
1674  *
1675  * Returns 1 if request is OK.
1676  */
1677 static int checkPerm(const char *path, const char *request)
1678 {
1679         Htaccess *cur;
1680         const char *p;
1681         const char *p0;
1682
1683         const char *prev = NULL;
1684
1685         /* This could stand some work */
1686         for (cur = g_auth; cur; cur = cur->next) {
1687                 size_t l;
1688
1689                 p0 = cur->before_colon;
1690                 if (prev != NULL && strcmp(prev, p0) != 0)
1691                         continue;       /* find next identical */
1692                 p = cur->after_colon;
1693                 if (DEBUG)
1694                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", p0, request);
1695
1696                 l = strlen(p0);
1697                 if (strncmp(p0, path, l) == 0
1698                  && (l == 1 || path[l] == '/' || path[l] == '\0')
1699                 ) {
1700                         char *u;
1701                         /* path match found.  Check request */
1702                         /* for check next /path:user:password */
1703                         prev = p0;
1704                         u = strchr(request, ':');
1705                         if (u == NULL) {
1706                                 /* bad request, ':' required */
1707                                 break;
1708                         }
1709
1710                         if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1711                                 char *cipher;
1712                                 char *pp;
1713
1714                                 if (strncmp(p, request, u - request) != 0) {
1715                                         /* user doesn't match */
1716                                         continue;
1717                                 }
1718                                 pp = strchr(p, ':');
1719                                 if (pp && pp[1] == '$' && pp[2] == '1'
1720                                  && pp[3] == '$' && pp[4]
1721                                 ) {
1722                                         pp++;
1723                                         cipher = pw_encrypt(u+1, pp);
1724                                         if (strcmp(cipher, pp) == 0)
1725                                                 goto set_remoteuser_var;   /* Ok */
1726                                         /* unauthorized */
1727                                         continue;
1728                                 }
1729                         }
1730
1731                         if (strcmp(p, request) == 0) {
1732  set_remoteuser_var:
1733                                 remoteuser = strdup(request);
1734                                 if (remoteuser)
1735                                         remoteuser[u - request] = '\0';
1736                                 return 1;   /* Ok */
1737                         }
1738                         /* unauthorized */
1739                 }
1740         } /* for */
1741
1742         return prev == NULL;
1743 }
1744 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1745
1746 #if ENABLE_FEATURE_HTTPD_PROXY
1747 static Htaccess_Proxy *find_proxy_entry(const char *url)
1748 {
1749         Htaccess_Proxy *p;
1750         for (p = proxy; p; p = p->next) {
1751                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1752                         return p;
1753         }
1754         return NULL;
1755 }
1756 #endif
1757
1758 /*
1759  * Handle timeouts
1760  */
1761 static void exit_on_signal(int sig) ATTRIBUTE_NORETURN;
1762 static void exit_on_signal(int sig ATTRIBUTE_UNUSED)
1763 {
1764         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1765 }
1766
1767 /*
1768  * Handle an incoming http request and exit.
1769  */
1770 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) ATTRIBUTE_NORETURN;
1771 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1772 {
1773         static const char request_GET[] ALIGN1 = "GET";
1774         struct stat sb;
1775         char *urlcopy;
1776         char *urlp;
1777         char *tptr;
1778         int ip_allowed;
1779 #if ENABLE_FEATURE_HTTPD_CGI
1780         static const char request_HEAD[] ALIGN1 = "HEAD";
1781         const char *prequest;
1782         char *cookie = NULL;
1783         char *content_type = NULL;
1784         unsigned long length = 0;
1785 #elif ENABLE_FEATURE_HTTPD_PROXY
1786 #define prequest request_GET
1787         unsigned long length = 0;
1788 #endif
1789         char http_major_version;
1790 #if ENABLE_FEATURE_HTTPD_PROXY
1791         char http_minor_version;
1792         char *header_buf = header_buf; /* for gcc */
1793         char *header_ptr = header_ptr;
1794         Htaccess_Proxy *proxy_entry;
1795 #endif
1796 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1797         int credentials = -1;  /* if not required this is Ok */
1798 #endif
1799
1800         /* Allocation of iobuf is postponed until now
1801          * (IOW, server process doesn't need to waste 8k) */
1802         iobuf = xmalloc(IOBUF_SIZE);
1803
1804         rmt_ip = 0;
1805         if (fromAddr->u.sa.sa_family == AF_INET) {
1806                 rmt_ip = ntohl(fromAddr->u.sin.sin_addr.s_addr);
1807         }
1808 #if ENABLE_FEATURE_IPV6
1809         if (fromAddr->u.sa.sa_family == AF_INET6
1810          && fromAddr->u.sin6.sin6_addr.s6_addr32[0] == 0
1811          && fromAddr->u.sin6.sin6_addr.s6_addr32[1] == 0
1812          && ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1813                 rmt_ip = ntohl(fromAddr->u.sin6.sin6_addr.s6_addr32[3]);
1814 #endif
1815         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1816                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->u.sa);
1817         }
1818         if (verbose) {
1819                 /* this trick makes -v logging much simpler */
1820                 applet_name = rmt_ip_str;
1821                 if (verbose > 2)
1822                         bb_error_msg("connected");
1823         }
1824
1825         /* Install timeout handler */
1826         signal_no_SA_RESTART_empty_mask(SIGALRM, exit_on_signal);
1827         alarm(HEADER_READ_TIMEOUT);
1828
1829         if (!get_line()) /* EOF or error or empty line */
1830                 send_headers_and_exit(HTTP_BAD_REQUEST);
1831
1832         /* Determine type of request (GET/POST) */
1833         urlp = strpbrk(iobuf, " \t");
1834         if (urlp == NULL)
1835                 send_headers_and_exit(HTTP_BAD_REQUEST);
1836         *urlp++ = '\0';
1837 #if ENABLE_FEATURE_HTTPD_CGI
1838         prequest = request_GET;
1839         if (strcasecmp(iobuf, prequest) != 0) {
1840                 prequest = request_HEAD;
1841                 if (strcasecmp(iobuf, prequest) != 0) {
1842                         prequest = "POST";
1843                         if (strcasecmp(iobuf, prequest) != 0)
1844                                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1845                 }
1846         }
1847 #else
1848         if (strcasecmp(iobuf, request_GET) != 0)
1849                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1850 #endif
1851         urlp = skip_whitespace(urlp);
1852         if (urlp[0] != '/')
1853                 send_headers_and_exit(HTTP_BAD_REQUEST);
1854
1855         /* Find end of URL and parse HTTP version, if any */
1856         http_major_version = '0';
1857         USE_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1858         tptr = strchrnul(urlp, ' ');
1859         /* Is it " HTTP/"? */
1860         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1861                 http_major_version = tptr[6];
1862                 USE_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1863         }
1864         *tptr = '\0';
1865
1866         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1867         urlcopy = alloca((tptr - urlp) + 2 + strlen(index_page));
1868         /*if (urlcopy == NULL)
1869          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1870         strcpy(urlcopy, urlp);
1871         /* NB: urlcopy ptr is never changed after this */
1872
1873         /* Extract url args if present */
1874         g_query = NULL;
1875         tptr = strchr(urlcopy, '?');
1876         if (tptr) {
1877                 *tptr++ = '\0';
1878                 g_query = tptr;
1879         }
1880
1881         /* Decode URL escape sequences */
1882         tptr = decodeString(urlcopy, 0);
1883         if (tptr == NULL)
1884                 send_headers_and_exit(HTTP_BAD_REQUEST);
1885         if (tptr == urlcopy + 1) {
1886                 /* '/' or NUL is encoded */
1887                 send_headers_and_exit(HTTP_NOT_FOUND);
1888         }
1889
1890         /* Canonicalize path */
1891         /* Algorithm stolen from libbb bb_simplify_path(),
1892          * but don't strdup and reducing trailing slash and protect out root */
1893         urlp = tptr = urlcopy;
1894         do {
1895                 if (*urlp == '/') {
1896                         /* skip duplicate (or initial) slash */
1897                         if (*tptr == '/') {
1898                                 continue;
1899                         }
1900                         if (*tptr == '.') {
1901                                 /* skip extra '.' */
1902                                 if (tptr[1] == '/' || !tptr[1]) {
1903                                         continue;
1904                                 }
1905                                 /* '..': be careful */
1906                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1907                                         ++tptr;
1908                                         if (urlp == urlcopy) /* protect root */
1909                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1910                                         while (*--urlp != '/') /* omit previous dir */;
1911                                                 continue;
1912                                 }
1913                         }
1914                 }
1915                 *++urlp = *tptr;
1916         } while (*++tptr);
1917         *++urlp = '\0';       /* so keep last character */
1918         tptr = urlp;          /* end ptr */
1919
1920         /* If URL is a directory, add '/' */
1921         if (tptr[-1] != '/') {
1922                 if (is_directory(urlcopy + 1, 1, &sb)) {
1923                         found_moved_temporarily = urlcopy;
1924                 }
1925         }
1926
1927         /* Log it */
1928         if (verbose > 1)
1929                 bb_error_msg("url:%s", urlcopy);
1930
1931         tptr = urlcopy;
1932         ip_allowed = checkPermIP();
1933         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1934                 /* have path1/path2 */
1935                 *tptr = '\0';
1936                 if (is_directory(urlcopy + 1, 1, &sb)) {
1937                         /* may be having subdir config */
1938                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1939                         ip_allowed = checkPermIP();
1940                 }
1941                 *tptr = '/';
1942         }
1943
1944 #if ENABLE_FEATURE_HTTPD_PROXY
1945         proxy_entry = find_proxy_entry(urlcopy);
1946         if (proxy_entry)
1947                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1948 #endif
1949
1950         if (http_major_version >= '0') {
1951                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1952
1953                 /* Read until blank line for HTTP version specified, else parse immediate */
1954                 while (1) {
1955                         alarm(HEADER_READ_TIMEOUT);
1956                         if (!get_line())
1957                                 break; /* EOF or error or empty line */
1958                         if (DEBUG)
1959                                 bb_error_msg("header: '%s'", iobuf);
1960
1961 #if ENABLE_FEATURE_HTTPD_PROXY
1962                         /* We need 2 more bytes for yet another "\r\n" -
1963                          * see near fdprintf(proxy_fd...) further below */
1964                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1965                                 int len = strlen(iobuf);
1966                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1967                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1968                                 memcpy(header_ptr, iobuf, len);
1969                                 header_ptr += len;
1970                                 header_ptr[0] = '\r';
1971                                 header_ptr[1] = '\n';
1972                                 header_ptr += 2;
1973                         }
1974 #endif
1975
1976 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1977                         /* Try and do our best to parse more lines */
1978                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1979                                 /* extra read only for POST */
1980                                 if (prequest != request_GET
1981 #if ENABLE_FEATURE_HTTPD_CGI
1982                                  && prequest != request_HEAD
1983 #endif
1984                                 ) {
1985                                         tptr = skip_whitespace(iobuf + sizeof("Content-length:") - 1);
1986                                         if (!tptr[0])
1987                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1988                                         /* not using strtoul: it ignores leading minus! */
1989                                         length = bb_strtou(tptr, NULL, 10);
1990                                         /* length is "ulong", but we need to pass it to int later */
1991                                         if (errno || length > INT_MAX)
1992                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1993                                 }
1994                         }
1995 #endif
1996 #if ENABLE_FEATURE_HTTPD_CGI
1997                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
1998                                 cookie = strdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
1999                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
2000                                 content_type = strdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
2001                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
2002                                 referer = strdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
2003                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
2004                                 user_agent = strdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
2005                         }
2006 #endif
2007 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2008                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
2009                                 /* We only allow Basic credentials.
2010                                  * It shows up as "Authorization: Basic <userid:password>" where
2011                                  * the userid:password is base64 encoded.
2012                                  */
2013                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
2014                                 if (STRNCASECMP(tptr, "Basic") != 0)
2015                                         continue;
2016                                 tptr += sizeof("Basic")-1;
2017                                 /* decodeBase64() skips whitespace itself */
2018                                 decodeBase64(tptr);
2019                                 credentials = checkPerm(urlcopy, tptr);
2020                         }
2021 #endif          /* FEATURE_HTTPD_BASIC_AUTH */
2022 #if ENABLE_FEATURE_HTTPD_RANGES
2023                         if (STRNCASECMP(iobuf, "Range:") == 0) {
2024                                 /* We know only bytes=NNN-[MMM] */
2025                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
2026                                 if (strncmp(s, "bytes=", 6) == 0) {
2027                                         s += sizeof("bytes=")-1;
2028                                         range_start = BB_STRTOOFF(s, &s, 10);
2029                                         if (s[0] != '-' || range_start < 0) {
2030                                                 range_start = 0;
2031                                         } else if (s[1]) {
2032                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2033                                                 if (errno || range_end < range_start)
2034                                                         range_start = 0;
2035                                         }
2036                                 }
2037                         }
2038 #endif
2039                 } /* while extra header reading */
2040         }
2041
2042         /* We are done reading headers, disable peer timeout */
2043         alarm(0);
2044
2045         if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || ip_allowed == 0) {
2046                 /* protect listing [/path]/httpd_conf or IP deny */
2047                 send_headers_and_exit(HTTP_FORBIDDEN);
2048         }
2049
2050 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2051         if (credentials <= 0 && checkPerm(urlcopy, ":") == 0) {
2052                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2053         }
2054 #endif
2055
2056         if (found_moved_temporarily) {
2057                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2058         }
2059
2060 #if ENABLE_FEATURE_HTTPD_PROXY
2061         if (proxy_entry != NULL) {
2062                 int proxy_fd;
2063                 len_and_sockaddr *lsa;
2064
2065                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2066                 if (proxy_fd < 0)
2067                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2068                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2069                 if (lsa == NULL)
2070                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2071                 if (connect(proxy_fd, &lsa->u.sa, lsa->len) < 0)
2072                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2073                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2074                                 prequest, /* GET or POST */
2075                                 proxy_entry->url_to, /* url part 1 */
2076                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2077                                 (g_query ? "?" : ""), /* "?" (maybe) */
2078                                 (g_query ? g_query : ""), /* query string (maybe) */
2079                                 http_major_version, http_minor_version);
2080                 header_ptr[0] = '\r';
2081                 header_ptr[1] = '\n';
2082                 header_ptr += 2;
2083                 write(proxy_fd, header_buf, header_ptr - header_buf);
2084                 free(header_buf); /* on the order of 8k, free it */
2085                 /* cgi_io_loop_and_exit needs to have two disctinct fds */
2086                 cgi_io_loop_and_exit(proxy_fd, dup(proxy_fd), length);
2087         }
2088 #endif
2089
2090         tptr = urlcopy + 1;      /* skip first '/' */
2091
2092 #if ENABLE_FEATURE_HTTPD_CGI
2093         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2094                 if (tptr[8] == '\0') {
2095                         /* protect listing "cgi-bin/" */
2096                         send_headers_and_exit(HTTP_FORBIDDEN);
2097                 }
2098                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2099         }
2100 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2101         {
2102                 char *suffix = strrchr(tptr, '.');
2103                 if (suffix) {
2104                         Htaccess *cur;
2105                         for (cur = script_i; cur; cur = cur->next) {
2106                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2107                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2108                                 }
2109                         }
2110                 }
2111         }
2112 #endif
2113         if (prequest != request_GET && prequest != request_HEAD) {
2114                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2115         }
2116 #endif  /* FEATURE_HTTPD_CGI */
2117
2118         if (urlp[-1] == '/')
2119                 strcpy(urlp, index_page);
2120         if (stat(tptr, &sb) == 0) {
2121                 file_size = sb.st_size;
2122                 last_mod = sb.st_mtime;
2123         }
2124 #if ENABLE_FEATURE_HTTPD_CGI
2125         else if (urlp[-1] == '/') {
2126                 /* It's a dir URL and there is no index.html
2127                  * Try cgi-bin/index.cgi */
2128                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2129                         urlp[0] = '\0';
2130                         g_query = urlcopy;
2131                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2132                 }
2133         }
2134 #endif
2135         /* else {
2136          *      fall through to send_file, it errors out if open fails
2137          * }
2138          */
2139
2140         send_file_and_exit(tptr,
2141 #if ENABLE_FEATURE_HTTPD_CGI
2142                 (prequest != request_HEAD ? SEND_HEADERS_AND_BODY : SEND_HEADERS)
2143 #else
2144                 SEND_HEADERS_AND_BODY
2145 #endif
2146         );
2147 }
2148
2149 /*
2150  * The main http server function.
2151  * Given a socket, listen for new connections and farm out
2152  * the processing as a [v]forked process.
2153  * Never returns.
2154  */
2155 #if BB_MMU
2156 static void mini_httpd(int server_socket) ATTRIBUTE_NORETURN;
2157 static void mini_httpd(int server_socket)
2158 {
2159         /* NB: it's best to not use xfuncs in this loop before fork().
2160          * Otherwise server may die on transient errors (temporary
2161          * out-of-memory condition, etc), which is Bad(tm).
2162          * Try to do any dangerous calls after fork.
2163          */
2164         while (1) {
2165                 int n;
2166                 len_and_sockaddr fromAddr;
2167
2168                 /* Wait for connections... */
2169                 fromAddr.len = LSA_SIZEOF_SA;
2170                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2171
2172                 if (n < 0)
2173                         continue;
2174                 /* set the KEEPALIVE option to cull dead connections */
2175                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2176
2177                 if (fork() == 0) {
2178                         /* child */
2179 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2180                         /* Do not reload config on HUP */
2181                         signal(SIGHUP, SIG_IGN);
2182 #endif
2183                         close(server_socket);
2184                         xmove_fd(n, 0);
2185                         xdup2(0, 1);
2186
2187                         handle_incoming_and_exit(&fromAddr);
2188                 }
2189                 /* parent, or fork failed */
2190                 close(n);
2191         } /* while (1) */
2192         /* never reached */
2193 }
2194 #else
2195 static void mini_httpd_nommu(int server_socket, int argc, char **argv) ATTRIBUTE_NORETURN;
2196 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2197 {
2198         char *argv_copy[argc + 2];
2199
2200         argv_copy[0] = argv[0];
2201         argv_copy[1] = (char*)"-i";
2202         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2203
2204         /* NB: it's best to not use xfuncs in this loop before vfork().
2205          * Otherwise server may die on transient errors (temporary
2206          * out-of-memory condition, etc), which is Bad(tm).
2207          * Try to do any dangerous calls after fork.
2208          */
2209         while (1) {
2210                 int n;
2211                 len_and_sockaddr fromAddr;
2212
2213                 /* Wait for connections... */
2214                 fromAddr.len = LSA_SIZEOF_SA;
2215                 n = accept(server_socket, &fromAddr.u.sa, &fromAddr.len);
2216
2217                 if (n < 0)
2218                         continue;
2219                 /* set the KEEPALIVE option to cull dead connections */
2220                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2221
2222                 if (vfork() == 0) {
2223                         /* child */
2224 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2225                         /* Do not reload config on HUP */
2226                         signal(SIGHUP, SIG_IGN);
2227 #endif
2228                         close(server_socket);
2229                         xmove_fd(n, 0);
2230                         xdup2(0, 1);
2231
2232                         /* Run a copy of ourself in inetd mode */
2233                         re_exec(argv_copy);
2234                 }
2235                 /* parent, or vfork failed */
2236                 close(n);
2237         } /* while (1) */
2238         /* never reached */
2239 }
2240 #endif
2241
2242 /*
2243  * Process a HTTP connection on stdin/out.
2244  * Never returns.
2245  */
2246 static void mini_httpd_inetd(void) ATTRIBUTE_NORETURN;
2247 static void mini_httpd_inetd(void)
2248 {
2249         len_and_sockaddr fromAddr;
2250
2251         fromAddr.len = LSA_SIZEOF_SA;
2252         getpeername(0, &fromAddr.u.sa, &fromAddr.len);
2253         handle_incoming_and_exit(&fromAddr);
2254 }
2255
2256 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2257 static void sighup_handler(int sig)
2258 {
2259         parse_conf(default_path_httpd_conf, sig == SIGHUP ? SIGNALED_PARSE : FIRST_PARSE);
2260
2261         signal_SA_RESTART_empty_mask(SIGHUP, sighup_handler);
2262 }
2263 #endif
2264
2265 enum {
2266         c_opt_config_file = 0,
2267         d_opt_decode_url,
2268         h_opt_home_httpd,
2269         USE_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2270         USE_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2271         USE_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2272         USE_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2273         p_opt_port      ,
2274         p_opt_inetd     ,
2275         p_opt_foreground,
2276         p_opt_verbose   ,
2277         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2278         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2279         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2280         OPT_ENCODE_URL  = USE_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2281         OPT_REALM       = USE_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2282         OPT_MD5         = USE_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2283         OPT_SETUID      = USE_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2284         OPT_PORT        = 1 << p_opt_port,
2285         OPT_INETD       = 1 << p_opt_inetd,
2286         OPT_FOREGROUND  = 1 << p_opt_foreground,
2287         OPT_VERBOSE     = 1 << p_opt_verbose,
2288 };
2289
2290
2291 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2292 int httpd_main(int argc ATTRIBUTE_UNUSED, char **argv)
2293 {
2294         int server_socket = server_socket; /* for gcc */
2295         unsigned opt;
2296         char *url_for_decode;
2297         USE_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2298         USE_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2299         USE_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2300         USE_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2301
2302         INIT_G();
2303
2304 #if ENABLE_LOCALE_SUPPORT
2305         /* Undo busybox.c: we want to speak English in http (dates etc) */
2306         setlocale(LC_TIME, "C");
2307 #endif
2308
2309         home_httpd = xrealloc_getcwd_or_warn(NULL);
2310         /* -v counts, -i implies -f */
2311         opt_complementary = "vv:if";
2312         /* We do not "absolutize" path given by -h (home) opt.
2313          * If user gives relative path in -h, $SCRIPT_FILENAME can end up
2314          * relative too. */
2315         opt = getopt32(argv, "c:d:h:"
2316                         USE_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2317                         USE_FEATURE_HTTPD_BASIC_AUTH("r:")
2318                         USE_FEATURE_HTTPD_AUTH_MD5("m:")
2319                         USE_FEATURE_HTTPD_SETUID("u:")
2320                         "p:ifv",
2321                         &configFile, &url_for_decode, &home_httpd
2322                         USE_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2323                         USE_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2324                         USE_FEATURE_HTTPD_AUTH_MD5(, &pass)
2325                         USE_FEATURE_HTTPD_SETUID(, &s_ugid)
2326                         , &bind_addr_or_port
2327                         , &verbose
2328                 );
2329         if (opt & OPT_DECODE_URL) {
2330                 fputs(decodeString(url_for_decode, 1), stdout);
2331                 return 0;
2332         }
2333 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2334         if (opt & OPT_ENCODE_URL) {
2335                 fputs(encodeString(url_for_encode), stdout);
2336                 return 0;
2337         }
2338 #endif
2339 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2340         if (opt & OPT_MD5) {
2341                 puts(pw_encrypt(pass, "$1$"));
2342                 return 0;
2343         }
2344 #endif
2345 #if ENABLE_FEATURE_HTTPD_SETUID
2346         if (opt & OPT_SETUID) {
2347                 if (!get_uidgid(&ugid, s_ugid, 1))
2348                         bb_error_msg_and_die("unknown user[:group] "
2349                                                 "name '%s'", s_ugid);
2350         }
2351 #endif
2352
2353 #if !BB_MMU
2354         if (!(opt & OPT_FOREGROUND)) {
2355                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2356         }
2357 #endif
2358
2359         xchdir(home_httpd);
2360         if (!(opt & OPT_INETD)) {
2361                 signal(SIGCHLD, SIG_IGN);
2362                 server_socket = openServer();
2363 #if ENABLE_FEATURE_HTTPD_SETUID
2364                 /* drop privileges */
2365                 if (opt & OPT_SETUID) {
2366                         if (ugid.gid != (gid_t)-1) {
2367                                 if (setgroups(1, &ugid.gid) == -1)
2368                                         bb_perror_msg_and_die("setgroups");
2369                                 xsetgid(ugid.gid);
2370                         }
2371                         xsetuid(ugid.uid);
2372                 }
2373 #endif
2374         }
2375
2376 #if 0 /*was #if ENABLE_FEATURE_HTTPD_CGI*/
2377         /* User can do it himself: 'env - PATH="$PATH" httpd'
2378          * We don't do it because we don't want to screw users
2379          * which want to do
2380          * 'env - VAR1=val1 VAR2=val2 httpd'
2381          * and have VAR1 and VAR2 values visible in their CGIs.
2382          * Besides, it is also smaller. */
2383         {
2384                 char *p = getenv("PATH");
2385                 /* env strings themself are not freed, no need to strdup(p): */
2386                 clearenv();
2387                 if (p)
2388                         putenv(p - 5);
2389 //              if (!(opt & OPT_INETD))
2390 //                      setenv_long("SERVER_PORT", ???);
2391         }
2392 #endif
2393
2394 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2395         if (!(opt & OPT_INETD))
2396                 sighup_handler(0);
2397 #endif
2398         parse_conf(default_path_httpd_conf, FIRST_PARSE);
2399
2400         xfunc_error_retval = 0;
2401         if (opt & OPT_INETD)
2402                 mini_httpd_inetd();
2403 #if BB_MMU
2404         if (!(opt & OPT_FOREGROUND))
2405                 bb_daemonize(0); /* don't change current directory */
2406         mini_httpd(server_socket); /* never returns */
2407 #else
2408         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2409 #endif
2410         /* return 0; */
2411 }