bzip2: make -d actually work
[people/mcb30/busybox.git] / 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  *
47  * P:/url:[http://]hostname[:port]/new/path
48  *                   # When /urlXXXXXX is requested, reverse proxy
49  *                   # it to http://hostname[:port]/new/pathXXXXXX
50  *
51  * /cgi-bin:foo:bar  # Require user foo, pwd bar on urls starting with /cgi-bin/
52  * /adm:admin:setup  # Require user admin, pwd setup on urls starting with /adm/
53  * /adm:toor:PaSsWd  # or user toor, pwd PaSsWd on urls starting with /adm/
54  * .au:audio/basic   # additional mime type for audio.au files
55  * *.php:/path/php   # running cgi.php scripts through an interpreter
56  *
57  * A/D may be as a/d or allow/deny - first char case insensitive
58  * Deny IP rules take precedence over allow rules.
59  *
60  *
61  * The Deny/Allow IP logic:
62  *
63  *  - Default is to allow all.  No addresses are denied unless
64  *         denied with a D: rule.
65  *  - Order of Deny/Allow rules is significant
66  *  - Deny rules take precedence over allow rules.
67  *  - If a deny all rule (D:*) is used it acts as a catch-all for unmatched
68  *       addresses.
69  *  - Specification of Allow all (A:*) is a no-op
70  *
71  * Example:
72  *   1. Allow only specified addresses
73  *     A:172.20          # Allow any address that begins with 172.20.
74  *     A:10.10.          # Allow any address that begins with 10.10.
75  *     A:127.0.0.1       # Allow local loopback connections
76  *     D:*               # Deny from other IP connections
77  *
78  *   2. Only deny specified addresses
79  *     D:1.2.3.        # deny from 1.2.3.0 - 1.2.3.255
80  *     D:2.3.4.        # deny from 2.3.4.0 - 2.3.4.255
81  *     A:*             # (optional line added for clarity)
82  *
83  * If a sub directory contains a config file it is parsed and merged with
84  * any existing settings as if it was appended to the original configuration.
85  *
86  * subdir paths are relative to the containing subdir and thus cannot
87  * affect the parent rules.
88  *
89  * Note that since the sub dir is parsed in the forked thread servicing the
90  * subdir http request, any merge is discarded when the process exits.  As a
91  * result, the subdir settings only have a lifetime of a single request.
92  *
93  * Custom error pages can contain an absolute path or be relative to
94  * 'home_httpd'. Error pages are to be static files (no CGI or script). Error
95  * page can only be defined in the root configuration file and are not taken
96  * into account in local (directories) config files.
97  *
98  * If -c is not set, an attempt will be made to open the default
99  * root configuration file.  If -c is set and the file is not found, the
100  * server exits with an error.
101  *
102  */
103
104 #include "libbb.h"
105 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
106 #include <sys/sendfile.h>
107 #endif
108
109 //#define DEBUG 1
110 #define DEBUG 0
111
112 #define IOBUF_SIZE 8192    /* IO buffer */
113
114 /* amount of buffering in a pipe */
115 #ifndef PIPE_BUF
116 # define PIPE_BUF 4096
117 #endif
118 #if PIPE_BUF >= IOBUF_SIZE
119 # error "PIPE_BUF >= IOBUF_SIZE"
120 #endif
121
122 #define HEADER_READ_TIMEOUT 60
123
124 static const char default_path_httpd_conf[] ALIGN1 = "/etc";
125 static const char httpd_conf[] ALIGN1 = "httpd.conf";
126 static const char HTTP_200[] ALIGN1 = "HTTP/1.0 200 OK\r\n";
127
128 typedef struct has_next_ptr {
129         struct has_next_ptr *next;
130 } has_next_ptr;
131
132 /* Must have "next" as a first member */
133 typedef struct Htaccess {
134         struct Htaccess *next;
135         char *after_colon;
136         char before_colon[1];  /* really bigger, must be last */
137 } Htaccess;
138
139 /* Must have "next" as a first member */
140 typedef struct Htaccess_IP {
141         struct Htaccess_IP *next;
142         unsigned ip;
143         unsigned mask;
144         int allow_deny;
145 } Htaccess_IP;
146
147 /* Must have "next" as a first member */
148 typedef struct Htaccess_Proxy {
149         struct Htaccess_Proxy *next;
150         char *url_from;
151         char *host_port;
152         char *url_to;
153 } Htaccess_Proxy;
154
155 enum {
156         HTTP_OK = 200,
157         HTTP_PARTIAL_CONTENT = 206,
158         HTTP_MOVED_TEMPORARILY = 302,
159         HTTP_BAD_REQUEST = 400,       /* malformed syntax */
160         HTTP_UNAUTHORIZED = 401, /* authentication needed, respond with auth hdr */
161         HTTP_NOT_FOUND = 404,
162         HTTP_FORBIDDEN = 403,
163         HTTP_REQUEST_TIMEOUT = 408,
164         HTTP_NOT_IMPLEMENTED = 501,   /* used for unrecognized requests */
165         HTTP_INTERNAL_SERVER_ERROR = 500,
166         HTTP_CONTINUE = 100,
167 #if 0   /* future use */
168         HTTP_SWITCHING_PROTOCOLS = 101,
169         HTTP_CREATED = 201,
170         HTTP_ACCEPTED = 202,
171         HTTP_NON_AUTHORITATIVE_INFO = 203,
172         HTTP_NO_CONTENT = 204,
173         HTTP_MULTIPLE_CHOICES = 300,
174         HTTP_MOVED_PERMANENTLY = 301,
175         HTTP_NOT_MODIFIED = 304,
176         HTTP_PAYMENT_REQUIRED = 402,
177         HTTP_BAD_GATEWAY = 502,
178         HTTP_SERVICE_UNAVAILABLE = 503, /* overload, maintenance */
179         HTTP_RESPONSE_SETSIZE = 0xffffffff
180 #endif
181 };
182
183 static const uint16_t http_response_type[] ALIGN2 = {
184         HTTP_OK,
185 #if ENABLE_FEATURE_HTTPD_RANGES
186         HTTP_PARTIAL_CONTENT,
187 #endif
188         HTTP_MOVED_TEMPORARILY,
189         HTTP_REQUEST_TIMEOUT,
190         HTTP_NOT_IMPLEMENTED,
191 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
192         HTTP_UNAUTHORIZED,
193 #endif
194         HTTP_NOT_FOUND,
195         HTTP_BAD_REQUEST,
196         HTTP_FORBIDDEN,
197         HTTP_INTERNAL_SERVER_ERROR,
198 #if 0   /* not implemented */
199         HTTP_CREATED,
200         HTTP_ACCEPTED,
201         HTTP_NO_CONTENT,
202         HTTP_MULTIPLE_CHOICES,
203         HTTP_MOVED_PERMANENTLY,
204         HTTP_NOT_MODIFIED,
205         HTTP_BAD_GATEWAY,
206         HTTP_SERVICE_UNAVAILABLE,
207 #endif
208 };
209
210 static const struct {
211         const char *name;
212         const char *info;
213 } http_response[ARRAY_SIZE(http_response_type)] = {
214         { "OK", NULL },
215 #if ENABLE_FEATURE_HTTPD_RANGES
216         { "Partial Content", NULL },
217 #endif
218         { "Found", NULL },
219         { "Request Timeout", "No request appeared within 60 seconds" },
220         { "Not Implemented", "The requested method is not recognized" },
221 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
222         { "Unauthorized", "" },
223 #endif
224         { "Not Found", "The requested URL was not found" },
225         { "Bad Request", "Unsupported method" },
226         { "Forbidden", ""  },
227         { "Internal Server Error", "Internal Server Error" },
228 #if 0   /* not implemented */
229         { "Created" },
230         { "Accepted" },
231         { "No Content" },
232         { "Multiple Choices" },
233         { "Moved Permanently" },
234         { "Not Modified" },
235         { "Bad Gateway", "" },
236         { "Service Unavailable", "" },
237 #endif
238 };
239
240
241 struct globals {
242         int verbose;            /* must be int (used by getopt32) */
243         smallint flg_deny_all;
244
245         unsigned rmt_ip;        /* used for IP-based allow/deny rules */
246         time_t last_mod;
247         char *rmt_ip_str;       /* for $REMOTE_ADDR and $REMOTE_PORT */
248         const char *bind_addr_or_port;
249
250         const char *g_query;
251         const char *configFile;
252         const char *home_httpd;
253
254         const char *found_mime_type;
255         const char *found_moved_temporarily;
256         Htaccess_IP *ip_a_d;    /* config allow/deny lines */
257
258         USE_FEATURE_HTTPD_BASIC_AUTH(const char *g_realm;)
259         USE_FEATURE_HTTPD_BASIC_AUTH(char *remoteuser;)
260         USE_FEATURE_HTTPD_CGI(char *referer;)
261         USE_FEATURE_HTTPD_CGI(char *user_agent;)
262
263         off_t file_size;        /* -1 - unknown */
264 #if ENABLE_FEATURE_HTTPD_RANGES
265         off_t range_start;
266         off_t range_end;
267         off_t range_len;
268 #endif
269
270 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
271         Htaccess *g_auth;       /* config user:password lines */
272 #endif
273 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
274         Htaccess *mime_a;       /* config mime types */
275 #endif
276 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
277         Htaccess *script_i;     /* config script interpreters */
278 #endif
279         char *iobuf;            /* [IOBUF_SIZE] */
280 #define hdr_buf bb_common_bufsiz1
281         char *hdr_ptr;
282         int hdr_cnt;
283 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
284         const char *http_error_page[ARRAY_SIZE(http_response_type)];
285 #endif
286 #if ENABLE_FEATURE_HTTPD_PROXY
287         Htaccess_Proxy *proxy;
288 #endif
289 };
290 #define G (*ptr_to_globals)
291 #define verbose           (G.verbose          )
292 #define flg_deny_all      (G.flg_deny_all     )
293 #define rmt_ip            (G.rmt_ip           )
294 #define bind_addr_or_port (G.bind_addr_or_port)
295 #define g_query           (G.g_query          )
296 #define configFile        (G.configFile       )
297 #define home_httpd        (G.home_httpd       )
298 #define found_mime_type   (G.found_mime_type  )
299 #define found_moved_temporarily (G.found_moved_temporarily)
300 #define last_mod          (G.last_mod         )
301 #define ip_a_d            (G.ip_a_d           )
302 #define g_realm           (G.g_realm          )
303 #define remoteuser        (G.remoteuser       )
304 #define referer           (G.referer          )
305 #define user_agent        (G.user_agent       )
306 #define file_size         (G.file_size        )
307 #if ENABLE_FEATURE_HTTPD_RANGES
308 #define range_start       (G.range_start      )
309 #define range_end         (G.range_end        )
310 #define range_len         (G.range_len        )
311 #endif
312 #define rmt_ip_str        (G.rmt_ip_str       )
313 #define g_auth            (G.g_auth           )
314 #define mime_a            (G.mime_a           )
315 #define script_i          (G.script_i         )
316 #define iobuf             (G.iobuf            )
317 #define hdr_ptr           (G.hdr_ptr          )
318 #define hdr_cnt           (G.hdr_cnt          )
319 #define http_error_page   (G.http_error_page  )
320 #define proxy             (G.proxy            )
321 #define INIT_G() do { \
322         PTR_TO_GLOBALS = xzalloc(sizeof(G)); \
323         USE_FEATURE_HTTPD_BASIC_AUTH(g_realm = "Web Server Authentication";) \
324         bind_addr_or_port = "80"; \
325         file_size = -1; \
326 } while (0)
327
328 #if !ENABLE_FEATURE_HTTPD_RANGES
329 enum {
330         range_start = 0,
331         range_end = MAXINT(off_t) - 1,
332         range_len = MAXINT(off_t),
333 };
334 #endif
335
336
337 #define STRNCASECMP(a, str) strncasecmp((a), (str), sizeof(str)-1)
338
339 /* Prototypes */
340 static void send_file_and_exit(const char *url, int headers) ATTRIBUTE_NORETURN;
341
342 static void free_llist(has_next_ptr **pptr)
343 {
344         has_next_ptr *cur = *pptr;
345         while (cur) {
346                 has_next_ptr *t = cur;
347                 cur = cur->next;
348                 free(t);
349         }
350         *pptr = NULL;
351 }
352
353 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
354  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
355  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
356 static ALWAYS_INLINE void free_Htaccess_list(Htaccess **pptr)
357 {
358         free_llist((has_next_ptr**)pptr);
359 }
360 #endif
361
362 static ALWAYS_INLINE void free_Htaccess_IP_list(Htaccess_IP **pptr)
363 {
364         free_llist((has_next_ptr**)pptr);
365 }
366
367 /* Returns presumed mask width in bits or < 0 on error.
368  * Updates strp, stores IP at provided pointer */
369 static int scan_ip(const char **strp, unsigned *ipp, unsigned char endc)
370 {
371         const char *p = *strp;
372         int auto_mask = 8;
373         unsigned ip = 0;
374         int j;
375
376         if (*p == '/')
377                 return -auto_mask;
378
379         for (j = 0; j < 4; j++) {
380                 unsigned octet;
381
382                 if ((*p < '0' || *p > '9') && *p != '/' && *p)
383                         return -auto_mask;
384                 octet = 0;
385                 while (*p >= '0' && *p <= '9') {
386                         octet *= 10;
387                         octet += *p - '0';
388                         if (octet > 255)
389                                 return -auto_mask;
390                         p++;
391                 }
392                 if (*p == '.')
393                         p++;
394                 if (*p != '/' && *p)
395                         auto_mask += 8;
396                 ip = (ip << 8) | octet;
397         }
398         if (*p) {
399                 if (*p != endc)
400                         return -auto_mask;
401                 p++;
402                 if (*p == '\0')
403                         return -auto_mask;
404         }
405         *ipp = ip;
406         *strp = p;
407         return auto_mask;
408 }
409
410 /* Returns 0 on success. Stores IP and mask at provided pointers */
411 static int scan_ip_mask(const char *str, unsigned *ipp, unsigned *maskp)
412 {
413         int i;
414         unsigned mask;
415         char *p;
416
417         i = scan_ip(&str, ipp, '/');
418         if (i < 0)
419                 return i;
420
421         if (*str) {
422                 /* there is /xxx after dotted-IP address */
423                 i = bb_strtou(str, &p, 10);
424                 if (*p == '.') {
425                         /* 'xxx' itself is dotted-IP mask, parse it */
426                         /* (return 0 (success) only if it has N.N.N.N form) */
427                         return scan_ip(&str, maskp, '\0') - 32;
428                 }
429                 if (*p)
430                         return -1;
431         }
432
433         if (i > 32)
434                 return -1;
435
436         if (sizeof(unsigned) == 4 && i == 32) {
437                 /* mask >>= 32 below may not work */
438                 mask = 0;
439         } else {
440                 mask = 0xffffffff;
441                 mask >>= i;
442         }
443         /* i == 0 -> *maskp = 0x00000000
444          * i == 1 -> *maskp = 0x80000000
445          * i == 4 -> *maskp = 0xf0000000
446          * i == 31 -> *maskp = 0xfffffffe
447          * i == 32 -> *maskp = 0xffffffff */
448         *maskp = (uint32_t)(~mask);
449         return 0;
450 }
451
452 /*
453  * Parse configuration file into in-memory linked list.
454  *
455  * The first non-white character is examined to determine if the config line
456  * is one of the following:
457  *    .ext:mime/type   # new mime type not compiled into httpd
458  *    [adAD]:from      # ip address allow/deny, * for wildcard
459  *    /path:user:pass  # username/password
460  *    Ennn:error.html  # error page for status nnn
461  *    P:/url:[http://]hostname[:port]/new/path # reverse proxy
462  *
463  * Any previous IP rules are discarded.
464  * If the flag argument is not SUBDIR_PARSE then all /path and mime rules
465  * are also discarded.  That is, previous settings are retained if flag is
466  * SUBDIR_PARSE.
467  * Error pages are only parsed on the main config file.
468  *
469  * path   Path where to look for httpd.conf (without filename).
470  * flag   Type of the parse request.
471  */
472 /* flag */
473 #define FIRST_PARSE          0
474 #define SUBDIR_PARSE         1
475 #define SIGNALED_PARSE       2
476 #define FIND_FROM_HTTPD_ROOT 3
477 static void parse_conf(const char *path, int flag)
478 {
479         FILE *f;
480 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
481         Htaccess *prev;
482 #endif
483 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
484  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
485  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
486         Htaccess *cur;
487 #endif
488         const char *cf = configFile;
489         char buf[160];
490         char *p0;
491         char *c, *p;
492         Htaccess_IP *pip;
493
494         /* discard old rules */
495         free_Htaccess_IP_list(&ip_a_d);
496         flg_deny_all = 0;
497 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
498  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
499  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
500         /* retain previous auth and mime config only for subdir parse */
501         if (flag != SUBDIR_PARSE) {
502 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
503                 free_Htaccess_list(&g_auth);
504 #endif
505 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
506                 free_Htaccess_list(&mime_a);
507 #endif
508 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
509                 free_Htaccess_list(&script_i);
510 #endif
511         }
512 #endif
513
514         if (flag == SUBDIR_PARSE || cf == NULL) {
515                 cf = alloca(strlen(path) + sizeof(httpd_conf) + 2);
516                 sprintf((char *)cf, "%s/%s", path, httpd_conf);
517         }
518
519         while ((f = fopen(cf, "r")) == NULL) {
520                 if (flag == SUBDIR_PARSE || flag == FIND_FROM_HTTPD_ROOT) {
521                         /* config file not found, no changes to config */
522                         return;
523                 }
524                 if (configFile && flag == FIRST_PARSE) /* if -c option given */
525                         bb_simple_perror_msg_and_die(cf);
526                 flag = FIND_FROM_HTTPD_ROOT;
527                 cf = httpd_conf;
528         }
529
530 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
531         prev = g_auth;
532 #endif
533         /* This could stand some work */
534         while ((p0 = fgets(buf, sizeof(buf), f)) != NULL) {
535                 c = NULL;
536                 for (p = p0; *p0 != '\0' && *p0 != '#'; p0++) {
537                         if (!isspace(*p0)) {
538                                 *p++ = *p0;
539                                 if (*p0 == ':' && c == NULL)
540                                         c = p;
541                         }
542                 }
543                 *p = '\0';
544
545                 /* test for empty or strange line */
546                 if (c == NULL || *c == '\0')
547                         continue;
548                 p0 = buf;
549                 if (*p0 == 'd')
550                         *p0 = 'D';
551                 if (*c == '*') {
552                         if (*p0 == 'D') {
553                                 /* memorize deny all */
554                                 flg_deny_all = 1;
555                         }
556                         /* skip default other "word:*" config lines */
557                         continue;
558                 }
559
560                 if (*p0 == 'a')
561                         *p0 = 'A';
562                 if (*p0 == 'A' || *p0 == 'D') {
563                         /* storing current config IP line */
564                         pip = xzalloc(sizeof(Htaccess_IP));
565                         if (pip) {
566                                 if (scan_ip_mask(c, &(pip->ip), &(pip->mask))) {
567                                         /* syntax IP{/mask} error detected, protect all */
568                                         *p0 = 'D';
569                                         pip->mask = 0;
570                                 }
571                                 pip->allow_deny = *p0;
572                                 if (*p0 == 'D') {
573                                         /* Deny:from_IP move top */
574                                         pip->next = ip_a_d;
575                                         ip_a_d = pip;
576                                 } else {
577                                         /* add to bottom A:form_IP config line */
578                                         Htaccess_IP *prev_IP = ip_a_d;
579
580                                         if (prev_IP == NULL) {
581                                                 ip_a_d = pip;
582                                         } else {
583                                                 while (prev_IP->next)
584                                                         prev_IP = prev_IP->next;
585                                                 prev_IP->next = pip;
586                                         }
587                                 }
588                         }
589                         continue;
590                 }
591
592 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
593                 if (flag == FIRST_PARSE && *p0 == 'E') {
594                         int i;
595                         /* error status code */
596                         int status = atoi(++p0);
597                         /* c already points at the character following ':' in parse loop */
598                         /* c = strchr(p0, ':'); c++; */
599                         if (status < HTTP_CONTINUE) {
600                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
601                                 continue;
602                         }
603
604                         /* then error page; find matching status */
605                         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
606                                 if (http_response_type[i] == status) {
607                                         http_error_page[i] = concat_path_file((*c == '/') ? NULL : home_httpd, c);
608                                         break;
609                                 }
610                         }
611                         continue;
612                 }
613 #endif
614
615 #if ENABLE_FEATURE_HTTPD_PROXY
616                 if (flag == FIRST_PARSE && *p0 == 'P') {
617                         /* P:/url:[http://]hostname[:port]/new/path */
618                         char *url_from, *host_port, *url_to;
619                         Htaccess_Proxy *proxy_entry;
620
621                         url_from = c;
622                         host_port = strchr(c, ':');
623                         if (host_port == NULL) {
624                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
625                                 continue;
626                         }
627                         *host_port++ = '\0';
628                         if (strncmp(host_port, "http://", 7) == 0)
629                                 c += 7;
630                         if (*host_port == '\0') {
631                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
632                                 continue;
633                         }
634                         url_to = strchr(host_port, '/');
635                         if (url_to == NULL) {
636                                 bb_error_msg("config error '%s' in '%s'", buf, cf);
637                                 continue;
638                         }
639                         *url_to = '\0';
640                         proxy_entry = xzalloc(sizeof(Htaccess_Proxy));
641                         proxy_entry->url_from = xstrdup(url_from);
642                         proxy_entry->host_port = xstrdup(host_port);
643                         *url_to = '/';
644                         proxy_entry->url_to = xstrdup(url_to);
645                         proxy_entry->next = proxy;
646                         proxy = proxy_entry;
647                         continue;
648                 }
649 #endif
650
651 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
652                 if (*p0 == '/') {
653                         /* make full path from httpd root / current_path / config_line_path */
654                         cf = (flag == SUBDIR_PARSE ? path : "");
655                         p0 = xmalloc(strlen(cf) + (c - buf) + 2 + strlen(c));
656                         c[-1] = '\0';
657                         sprintf(p0, "/%s%s", cf, buf);
658
659                         /* another call bb_simplify_path */
660                         cf = p = p0;
661
662                         do {
663                                 if (*p == '/') {
664                                         if (*cf == '/') {    /* skip duplicate (or initial) slash */
665                                                 continue;
666                                         }
667                                         if (*cf == '.') {
668                                                 if (cf[1] == '/' || cf[1] == '\0') { /* remove extra '.' */
669                                                         continue;
670                                                 }
671                                                 if ((cf[1] == '.') && (cf[2] == '/' || cf[2] == '\0')) {
672                                                         ++cf;
673                                                         if (p > p0) {
674                                                                 while (*--p != '/') /* omit previous dir */;
675                                                         }
676                                                         continue;
677                                                 }
678                                         }
679                                 }
680                                 *++p = *cf;
681                         } while (*++cf);
682
683                         if ((p == p0) || (*p != '/')) {      /* not a trailing slash */
684                                 ++p;                             /* so keep last character */
685                         }
686                         *p = ':';
687                         strcpy(p + 1, c);
688                 }
689 #endif
690
691 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH \
692  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES \
693  || ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
694                 /* storing current config line */
695                 cur = xzalloc(sizeof(Htaccess) + strlen(p0));
696                 cf = strcpy(cur->before_colon, p0);
697 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
698                 if (*p0 == '/')
699                         free(p0);
700 #endif
701                 c = strchr(cf, ':');
702                 *c++ = '\0';
703                 cur->after_colon = c;
704 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
705                 if (*cf == '.') {
706                         /* config .mime line move top for overwrite previous */
707                         cur->next = mime_a;
708                         mime_a = cur;
709                         continue;
710                 }
711 #endif
712 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
713                 if (*cf == '*' && cf[1] == '.') {
714                         /* config script interpreter line move top for overwrite previous */
715                         cur->next = script_i;
716                         script_i = cur;
717                         continue;
718                 }
719 #endif
720 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
721                 if (prev == NULL) {
722                         /* first line */
723                         g_auth = prev = cur;
724                 } else {
725                         /* sort path, if current length eq or bigger then move up */
726                         Htaccess *prev_hti = g_auth;
727                         size_t l = strlen(cf);
728                         Htaccess *hti;
729
730                         for (hti = prev_hti; hti; hti = hti->next) {
731                                 if (l >= strlen(hti->before_colon)) {
732                                         /* insert before hti */
733                                         cur->next = hti;
734                                         if (prev_hti != hti) {
735                                                 prev_hti->next = cur;
736                                         } else {
737                                                 /* insert as top */
738                                                 g_auth = cur;
739                                         }
740                                         break;
741                                 }
742                                 if (prev_hti != hti)
743                                         prev_hti = prev_hti->next;
744                         }
745                         if (!hti) {       /* not inserted, add to bottom */
746                                 prev->next = cur;
747                                 prev = cur;
748                         }
749                 }
750 #endif /* BASIC_AUTH */
751 #endif /* BASIC_AUTH || MIME_TYPES || SCRIPT_INTERPR */
752          } /* while (fgets) */
753          fclose(f);
754 }
755
756 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
757 /*
758  * Given a string, html-encode special characters.
759  * This is used for the -e command line option to provide an easy way
760  * for scripts to encode result data without confusing browsers.  The
761  * returned string pointer is memory allocated by malloc().
762  *
763  * Returns a pointer to the encoded string (malloced).
764  */
765 static char *encodeString(const char *string)
766 {
767         /* take the simple route and encode everything */
768         /* could possibly scan once to get length.     */
769         int len = strlen(string);
770         char *out = xmalloc(len * 6 + 1);
771         char *p = out;
772         char ch;
773
774         while ((ch = *string++)) {
775                 /* very simple check for what to encode */
776                 if (isalnum(ch))
777                         *p++ = ch;
778                 else
779                         p += sprintf(p, "&#%d;", (unsigned char) ch);
780         }
781         *p = '\0';
782         return out;
783 }
784 #endif          /* FEATURE_HTTPD_ENCODE_URL_STR */
785
786 /*
787  * Given a URL encoded string, convert it to plain ascii.
788  * Since decoding always makes strings smaller, the decode is done in-place.
789  * Thus, callers should strdup() the argument if they do not want the
790  * argument modified.  The return is the original pointer, allowing this
791  * function to be easily used as arguments to other functions.
792  *
793  * string    The first string to decode.
794  * option_d  1 if called for httpd -d
795  *
796  * Returns a pointer to the decoded string (same as input).
797  */
798 static unsigned hex_to_bin(unsigned char c)
799 {
800         unsigned v;
801
802         v = c - '0';
803         if (v <= 9)
804                 return v;
805         /* c | 0x20: letters to lower case, non-letters
806          * to (potentially different) non-letters */
807         v = (unsigned)(c | 0x20) - 'a';
808         if (v <= 5)
809                 return v + 10;
810         return ~0;
811 }
812 /* For testing:
813 void t(char c) { printf("'%c'(%u) %u\n", c, c, hex_to_bin(c)); }
814 int main() { t(0x10); t(0x20); t('0'); t('9'); t('A'); t('F'); t('a'); t('f');
815 t('0'-1); t('9'+1); t('A'-1); t('F'+1); t('a'-1); t('f'+1); return 0; }
816 */
817 static char *decodeString(char *orig, int option_d)
818 {
819         /* note that decoded string is always shorter than original */
820         char *string = orig;
821         char *ptr = string;
822         char c;
823
824         while ((c = *ptr++) != '\0') {
825                 unsigned v;
826
827                 if (option_d && c == '+') {
828                         *string++ = ' ';
829                         continue;
830                 }
831                 if (c != '%') {
832                         *string++ = c;
833                         continue;
834                 }
835                 v = hex_to_bin(ptr[0]);
836                 if (v > 15) {
837  bad_hex:
838                         if (!option_d)
839                                 return NULL;
840                         *string++ = '%';
841                         continue;
842                 }
843                 v = (v * 16) | hex_to_bin(ptr[1]);
844                 if (v > 255)
845                         goto bad_hex;
846                 if (!option_d && (v == '/' || v == '\0')) {
847                         /* caller takes it as indication of invalid
848                          * (dangerous wrt exploits) chars */
849                         return orig + 1;
850                 }
851                 *string++ = v;
852                 ptr += 2;
853         }
854         *string = '\0';
855         return orig;
856 }
857
858 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
859 /*
860  * Decode a base64 data stream as per rfc1521.
861  * Note that the rfc states that non base64 chars are to be ignored.
862  * Since the decode always results in a shorter size than the input,
863  * it is OK to pass the input arg as an output arg.
864  * Parameter: a pointer to a base64 encoded string.
865  * Decoded data is stored in-place.
866  */
867 static void decodeBase64(char *Data)
868 {
869         const unsigned char *in = (const unsigned char *)Data;
870         /* The decoded size will be at most 3/4 the size of the encoded */
871         unsigned ch = 0;
872         int i = 0;
873
874         while (*in) {
875                 int t = *in++;
876
877                 if (t >= '0' && t <= '9')
878                         t = t - '0' + 52;
879                 else if (t >= 'A' && t <= 'Z')
880                         t = t - 'A';
881                 else if (t >= 'a' && t <= 'z')
882                         t = t - 'a' + 26;
883                 else if (t == '+')
884                         t = 62;
885                 else if (t == '/')
886                         t = 63;
887                 else if (t == '=')
888                         t = 0;
889                 else
890                         continue;
891
892                 ch = (ch << 6) | t;
893                 i++;
894                 if (i == 4) {
895                         *Data++ = (char) (ch >> 16);
896                         *Data++ = (char) (ch >> 8);
897                         *Data++ = (char) ch;
898                         i = 0;
899                 }
900         }
901         *Data = '\0';
902 }
903 #endif
904
905 /*
906  * Create a listen server socket on the designated port.
907  */
908 static int openServer(void)
909 {
910         unsigned n = bb_strtou(bind_addr_or_port, NULL, 10);
911         if (!errno && n && n <= 0xffff)
912                 n = create_and_bind_stream_or_die(NULL, n);
913         else
914                 n = create_and_bind_stream_or_die(bind_addr_or_port, 80);
915         xlisten(n, 9);
916         return n;
917 }
918
919 /*
920  * Log the connection closure and exit.
921  */
922 static void log_and_exit(void) ATTRIBUTE_NORETURN;
923 static void log_and_exit(void)
924 {
925         /* Paranoia. IE said to be buggy. It may send some extra data
926          * or be confused by us just exiting without SHUT_WR. Oh well. */
927         shutdown(1, SHUT_WR);
928         ndelay_on(0);
929         while (read(0, iobuf, IOBUF_SIZE) > 0)
930                 continue;
931
932         if (verbose > 2)
933                 bb_error_msg("closed");
934         _exit(xfunc_error_retval);
935 }
936
937 /*
938  * Create and send HTTP response headers.
939  * The arguments are combined and sent as one write operation.  Note that
940  * IE will puke big-time if the headers are not sent in one packet and the
941  * second packet is delayed for any reason.
942  * responseNum - the result code to send.
943  */
944 static void send_headers(int responseNum)
945 {
946         static const char RFC1123FMT[] ALIGN1 = "%a, %d %b %Y %H:%M:%S GMT";
947
948         const char *responseString = "";
949         const char *infoString = NULL;
950         const char *mime_type;
951 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
952         const char *error_page = 0;
953 #endif
954         unsigned i;
955         time_t timer = time(0);
956         char tmp_str[80];
957         int len;
958
959         for (i = 0; i < ARRAY_SIZE(http_response_type); i++) {
960                 if (http_response_type[i] == responseNum) {
961                         responseString = http_response[i].name;
962                         infoString = http_response[i].info;
963 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
964                         error_page = http_error_page[i];
965 #endif
966                         break;
967                 }
968         }
969         /* error message is HTML */
970         mime_type = responseNum == HTTP_OK ?
971                                 found_mime_type : "text/html";
972
973         if (verbose)
974                 bb_error_msg("response:%u", responseNum);
975
976         /* emit the current date */
977         strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&timer));
978         len = sprintf(iobuf,
979                         "HTTP/1.0 %d %s\r\nContent-type: %s\r\n"
980                         "Date: %s\r\nConnection: close\r\n",
981                         responseNum, responseString, mime_type, tmp_str);
982
983 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
984         if (responseNum == HTTP_UNAUTHORIZED) {
985                 len += sprintf(iobuf + len,
986                                 "WWW-Authenticate: Basic realm=\"%s\"\r\n",
987                                 g_realm);
988         }
989 #endif
990         if (responseNum == HTTP_MOVED_TEMPORARILY) {
991                 len += sprintf(iobuf + len, "Location: %s/%s%s\r\n",
992                                 found_moved_temporarily,
993                                 (g_query ? "?" : ""),
994                                 (g_query ? g_query : ""));
995         }
996
997 #if ENABLE_FEATURE_HTTPD_ERROR_PAGES
998         if (error_page && !access(error_page, R_OK)) {
999                 strcat(iobuf, "\r\n");
1000                 len += 2;
1001
1002                 if (DEBUG)
1003                         fprintf(stderr, "headers: '%s'\n", iobuf);
1004                 full_write(1, iobuf, len);
1005                 if (DEBUG)
1006                         fprintf(stderr, "writing error page: '%s'\n", error_page);
1007                 return send_file_and_exit(error_page, FALSE);
1008         }
1009 #endif
1010
1011         if (file_size != -1) {    /* file */
1012                 strftime(tmp_str, sizeof(tmp_str), RFC1123FMT, gmtime(&last_mod));
1013 #if ENABLE_FEATURE_HTTPD_RANGES
1014                 if (responseNum == HTTP_PARTIAL_CONTENT) {
1015                         len += sprintf(iobuf + len, "Content-Range: bytes %"OFF_FMT"d-%"OFF_FMT"d/%"OFF_FMT"d\r\n",
1016                                         range_start,
1017                                         range_end,
1018                                         file_size);
1019                         file_size = range_end - range_start + 1;
1020                 }
1021 #endif
1022                 len += sprintf(iobuf + len,
1023 #if ENABLE_FEATURE_HTTPD_RANGES
1024                         "Accept-Ranges: bytes\r\n"
1025 #endif
1026                         "Last-Modified: %s\r\n%s %"OFF_FMT"d\r\n",
1027                                 tmp_str,
1028                                 "Content-length:",
1029                                 file_size
1030                 );
1031         }
1032         iobuf[len++] = '\r';
1033         iobuf[len++] = '\n';
1034         if (infoString) {
1035                 len += sprintf(iobuf + len,
1036                                 "<HTML><HEAD><TITLE>%d %s</TITLE></HEAD>\n"
1037                                 "<BODY><H1>%d %s</H1>\n%s\n</BODY></HTML>\n",
1038                                 responseNum, responseString,
1039                                 responseNum, responseString, infoString);
1040         }
1041         if (DEBUG)
1042                 fprintf(stderr, "headers: '%s'\n", iobuf);
1043         if (full_write(1, iobuf, len) != len) {
1044                 if (verbose > 1)
1045                         bb_perror_msg("error");
1046                 log_and_exit();
1047         }
1048 }
1049
1050 static void send_headers_and_exit(int responseNum) ATTRIBUTE_NORETURN;
1051 static void send_headers_and_exit(int responseNum)
1052 {
1053         send_headers(responseNum);
1054         log_and_exit();
1055 }
1056
1057 /*
1058  * Read from the socket until '\n' or EOF. '\r' chars are removed.
1059  * '\n' is replaced with NUL.
1060  * Return number of characters read or 0 if nothing is read
1061  * ('\r' and '\n' are not counted).
1062  * Data is returned in iobuf.
1063  */
1064 static int get_line(void)
1065 {
1066         int count = 0;
1067         char c;
1068
1069         while (1) {
1070                 if (hdr_cnt <= 0) {
1071                         hdr_cnt = safe_read(0, hdr_buf, sizeof(hdr_buf));
1072                         if (hdr_cnt <= 0)
1073                                 break;
1074                         hdr_ptr = hdr_buf;
1075                 }
1076                 iobuf[count] = c = *hdr_ptr++;
1077                 hdr_cnt--;
1078
1079                 if (c == '\r')
1080                         continue;
1081                 if (c == '\n') {
1082                         iobuf[count] = '\0';
1083                         return count;
1084                 }
1085                 if (count < (IOBUF_SIZE - 1))      /* check overflow */
1086                         count++;
1087         }
1088         return count;
1089 }
1090
1091 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1092
1093 /* gcc 4.2.1 fares better with NOINLINE */
1094 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len) ATTRIBUTE_NORETURN;
1095 static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post_len)
1096 {
1097         enum { FROM_CGI = 1, TO_CGI = 2 }; /* indexes in pfd[] */
1098         struct pollfd pfd[3];
1099         int out_cnt; /* we buffer a bit of initial CGI output */
1100         int count;
1101
1102         /* iobuf is used for CGI -> network data,
1103          * hdr_buf is for network -> CGI data (POSTDATA) */
1104
1105         /* If CGI dies, we still want to correctly finish reading its output
1106          * and send it to the peer. So please no SIGPIPEs! */
1107         signal(SIGPIPE, SIG_IGN);
1108
1109         // We inconsistently handle a case when more POSTDATA from network
1110         // is coming than we expected. We may give *some part* of that
1111         // extra data to CGI.
1112
1113         //if (hdr_cnt > post_len) {
1114         //      /* We got more POSTDATA from network than we expected */
1115         //      hdr_cnt = post_len;
1116         //}
1117         post_len -= hdr_cnt;
1118         /* post_len - number of POST bytes not yet read from network */
1119
1120         /* NB: breaking out of this loop jumps to log_and_exit() */
1121         out_cnt = 0;
1122         while (1) {
1123                 memset(pfd, 0, sizeof(pfd));
1124
1125                 pfd[FROM_CGI].fd = fromCgi_rd;
1126                 pfd[FROM_CGI].events = POLLIN;
1127
1128                 if (toCgi_wr) {
1129                         pfd[TO_CGI].fd = toCgi_wr;
1130                         if (hdr_cnt > 0) {
1131                                 pfd[TO_CGI].events = POLLOUT;
1132                         } else if (post_len > 0) {
1133                                 pfd[0].events = POLLIN;
1134                         } else {
1135                                 /* post_len <= 0 && hdr_cnt <= 0:
1136                                  * no more POST data to CGI,
1137                                  * let CGI see EOF on CGI's stdin */
1138                                 close(toCgi_wr);
1139                                 toCgi_wr = 0;
1140                         }
1141                 }
1142
1143                 /* Now wait on the set of sockets */
1144                 count = safe_poll(pfd, 3, -1);
1145                 if (count <= 0) {
1146 #if 0
1147                         if (waitpid(pid, &status, WNOHANG) <= 0) {
1148                                 /* Weird. CGI didn't exit and no fd's
1149                                  * are ready, yet poll returned?! */
1150                                 continue;
1151                         }
1152                         if (DEBUG && WIFEXITED(status))
1153                                 bb_error_msg("CGI exited, status=%d", WEXITSTATUS(status));
1154                         if (DEBUG && WIFSIGNALED(status))
1155                                 bb_error_msg("CGI killed, signal=%d", WTERMSIG(status));
1156 #endif
1157                         break;
1158                 }
1159
1160                 if (pfd[TO_CGI].revents) {
1161                         /* hdr_cnt > 0 here due to the way pfd[TO_CGI].events set */
1162                         /* Have data from peer and can write to CGI */
1163                         count = safe_write(toCgi_wr, hdr_ptr, hdr_cnt);
1164                         /* Doesn't happen, we dont use nonblocking IO here
1165                          *if (count < 0 && errno == EAGAIN) {
1166                          *      ...
1167                          *} else */
1168                         if (count > 0) {
1169                                 hdr_ptr += count;
1170                                 hdr_cnt -= count;
1171                         } else {
1172                                 /* EOF/broken pipe to CGI, stop piping POST data */
1173                                 hdr_cnt = post_len = 0;
1174                         }
1175                 }
1176
1177                 if (pfd[0].revents) {
1178                         /* post_len > 0 && hdr_cnt == 0 here */
1179                         /* We expect data, prev data portion is eaten by CGI
1180                          * and there *is* data to read from the peer
1181                          * (POSTDATA) */
1182                         //count = post_len > (int)sizeof(hdr_buf) ? (int)sizeof(hdr_buf) : post_len;
1183                         //count = safe_read(0, hdr_buf, count);
1184                         count = safe_read(0, hdr_buf, sizeof(hdr_buf));
1185                         if (count > 0) {
1186                                 hdr_cnt = count;
1187                                 hdr_ptr = hdr_buf;
1188                                 post_len -= count;
1189                         } else {
1190                                 /* no more POST data can be read */
1191                                 post_len = 0;
1192                         }
1193                 }
1194
1195                 if (pfd[FROM_CGI].revents) {
1196                         /* There is something to read from CGI */
1197                         char *rbuf = iobuf;
1198
1199                         /* Are we still buffering CGI output? */
1200                         if (out_cnt >= 0) {
1201                                 /* HTTP_200[] has single "\r\n" at the end.
1202                                  * According to http://hoohoo.ncsa.uiuc.edu/cgi/out.html,
1203                                  * CGI scripts MUST send their own header terminated by
1204                                  * empty line, then data. That's why we have only one
1205                                  * <cr><lf> pair here. We will output "200 OK" line
1206                                  * if needed, but CGI still has to provide blank line
1207                                  * between header and body */
1208
1209                                 /* Must use safe_read, not full_read, because
1210                                  * CGI may output a few first bytes and then wait
1211                                  * for POSTDATA without closing stdout.
1212                                  * With full_read we may wait here forever. */
1213                                 count = safe_read(fromCgi_rd, rbuf + out_cnt, PIPE_BUF - 8);
1214                                 if (count <= 0) {
1215                                         /* eof (or error) and there was no "HTTP",
1216                                          * so write it, then write received data */
1217                                         if (out_cnt) {
1218                                                 full_write(1, HTTP_200, sizeof(HTTP_200)-1);
1219                                                 full_write(1, rbuf, out_cnt);
1220                                         }
1221                                         break; /* CGI stdout is closed, exiting */
1222                                 }
1223                                 out_cnt += count;
1224                                 count = 0;
1225                                 /* "Status" header format is: "Status: 302 Redirected\r\n" */
1226                                 if (out_cnt >= 8 && memcmp(rbuf, "Status: ", 8) == 0) {
1227                                         /* send "HTTP/1.0 " */
1228                                         if (full_write(1, HTTP_200, 9) != 9)
1229                                                 break;
1230                                         rbuf += 8; /* skip "Status: " */
1231                                         count = out_cnt - 8;
1232                                         out_cnt = -1; /* buffering off */
1233                                 } else if (out_cnt >= 4) {
1234                                         /* Did CGI add "HTTP"? */
1235                                         if (memcmp(rbuf, HTTP_200, 4) != 0) {
1236                                                 /* there is no "HTTP", do it ourself */
1237                                                 if (full_write(1, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1)
1238                                                         break;
1239                                         }
1240                                         /* Commented out:
1241                                         if (!strstr(rbuf, "ontent-")) {
1242                                                 full_write(s, "Content-type: text/plain\r\n\r\n", 28);
1243                                         }
1244                                          * Counter-example of valid CGI without Content-type:
1245                                          * echo -en "HTTP/1.0 302 Found\r\n"
1246                                          * echo -en "Location: http://www.busybox.net\r\n"
1247                                          * echo -en "\r\n"
1248                                          */
1249                                         count = out_cnt;
1250                                         out_cnt = -1; /* buffering off */
1251                                 }
1252                         } else {
1253                                 count = safe_read(fromCgi_rd, rbuf, PIPE_BUF);
1254                                 if (count <= 0)
1255                                         break;  /* eof (or error) */
1256                         }
1257                         if (full_write(1, rbuf, count) != count)
1258                                 break;
1259                         if (DEBUG)
1260                                 fprintf(stderr, "cgi read %d bytes: '%.*s'\n", count, count, rbuf);
1261                 } /* if (pfd[FROM_CGI].revents) */
1262         } /* while (1) */
1263         log_and_exit();
1264 }
1265 #endif
1266
1267 #if ENABLE_FEATURE_HTTPD_CGI
1268
1269 static void setenv1(const char *name, const char *value)
1270 {
1271         setenv(name, value ? value : "", 1);
1272 }
1273
1274 /*
1275  * Spawn CGI script, forward CGI's stdin/out <=> network
1276  *
1277  * Environment variables are set up and the script is invoked with pipes
1278  * for stdin/stdout.  If a POST is being done the script is fed the POST
1279  * data in addition to setting the QUERY_STRING variable (for GETs or POSTs).
1280  *
1281  * Parameters:
1282  * const char *url              The requested URL (with leading /).
1283  * int post_len                 Length of the POST body.
1284  * const char *cookie           For set HTTP_COOKIE.
1285  * const char *content_type     For set CONTENT_TYPE.
1286  */
1287 static void send_cgi_and_exit(
1288                 const char *url,
1289                 const char *request,
1290                 int post_len,
1291                 const char *cookie,
1292                 const char *content_type) ATTRIBUTE_NORETURN;
1293 static void send_cgi_and_exit(
1294                 const char *url,
1295                 const char *request,
1296                 int post_len,
1297                 const char *cookie,
1298                 const char *content_type)
1299 {
1300         struct { int rd; int wr; } fromCgi;  /* CGI -> httpd pipe */
1301         struct { int rd; int wr; } toCgi;    /* httpd -> CGI pipe */
1302         char *fullpath;
1303         char *script;
1304         char *purl;
1305         int pid;
1306
1307         /*
1308          * We are mucking with environment _first_ and then vfork/exec,
1309          * this allows us to use vfork safely. Parent don't care about
1310          * these environment changes anyway.
1311          */
1312
1313         /*
1314          * Find PATH_INFO.
1315          */
1316         purl = xstrdup(url);
1317         script = purl;
1318         while ((script = strchr(script + 1, '/')) != NULL) {
1319                 /* have script.cgi/PATH_INFO or dirs/script.cgi[/PATH_INFO] */
1320                 struct stat sb;
1321
1322                 *script = '\0';
1323                 if (!is_directory(purl + 1, 1, &sb)) {
1324                         /* not directory, found script.cgi/PATH_INFO */
1325                         *script = '/';
1326                         break;
1327                 }
1328                 *script = '/';          /* is directory, find next '/' */
1329         }
1330         setenv1("PATH_INFO", script);   /* set /PATH_INFO or "" */
1331         setenv1("REQUEST_METHOD", request);
1332         if (g_query) {
1333                 putenv(xasprintf("%s=%s?%s", "REQUEST_URI", purl, g_query));
1334         } else {
1335                 setenv1("REQUEST_URI", purl);
1336         }
1337         if (script != NULL)
1338                 *script = '\0';         /* cut off /PATH_INFO */
1339
1340         /* SCRIPT_FILENAME required by PHP in CGI mode */
1341         fullpath = concat_path_file(home_httpd, purl);
1342         setenv1("SCRIPT_FILENAME", fullpath);
1343         /* set SCRIPT_NAME as full path: /cgi-bin/dirs/script.cgi */
1344         setenv1("SCRIPT_NAME", purl);
1345         /* http://hoohoo.ncsa.uiuc.edu/cgi/env.html:
1346          * QUERY_STRING: The information which follows the ? in the URL
1347          * which referenced this script. This is the query information.
1348          * It should not be decoded in any fashion. This variable
1349          * should always be set when there is query information,
1350          * regardless of command line decoding. */
1351         /* (Older versions of bbox seem to do some decoding) */
1352         setenv1("QUERY_STRING", g_query);
1353         putenv((char*)"SERVER_SOFTWARE=busybox httpd/"BB_VER);
1354         putenv((char*)"SERVER_PROTOCOL=HTTP/1.0");
1355         putenv((char*)"GATEWAY_INTERFACE=CGI/1.1");
1356         /* Having _separate_ variables for IP and port defeats
1357          * the purpose of having socket abstraction. Which "port"
1358          * are you using on Unix domain socket?
1359          * IOW - REMOTE_PEER="1.2.3.4:56" makes much more sense.
1360          * Oh well... */
1361         {
1362                 char *p = rmt_ip_str ? rmt_ip_str : (char*)"";
1363                 char *cp = strrchr(p, ':');
1364                 if (ENABLE_FEATURE_IPV6 && cp && strchr(cp, ']'))
1365                         cp = NULL;
1366                 if (cp) *cp = '\0'; /* delete :PORT */
1367                 setenv1("REMOTE_ADDR", p);
1368                 if (cp) {
1369                         *cp = ':';
1370 #if ENABLE_FEATURE_HTTPD_SET_REMOTE_PORT_TO_ENV
1371                         setenv1("REMOTE_PORT", cp + 1);
1372 #endif
1373                 }
1374         }
1375         setenv1("HTTP_USER_AGENT", user_agent);
1376         if (post_len)
1377                 putenv(xasprintf("CONTENT_LENGTH=%d", post_len));
1378         if (cookie)
1379                 setenv1("HTTP_COOKIE", cookie);
1380         if (content_type)
1381                 setenv1("CONTENT_TYPE", content_type);
1382 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1383         if (remoteuser) {
1384                 setenv1("REMOTE_USER", remoteuser);
1385                 putenv((char*)"AUTH_TYPE=Basic");
1386         }
1387 #endif
1388         if (referer)
1389                 setenv1("HTTP_REFERER", referer);
1390
1391         xpipe(&fromCgi.rd);
1392         xpipe(&toCgi.rd);
1393
1394         pid = vfork();
1395         if (pid < 0) {
1396                 /* TODO: log perror? */
1397                 log_and_exit();
1398         }
1399
1400         if (!pid) {
1401                 /* Child process */
1402                 xfunc_error_retval = 242;
1403
1404                 xmove_fd(toCgi.rd, 0);  /* replace stdin with the pipe */
1405                 xmove_fd(fromCgi.wr, 1);  /* replace stdout with the pipe */
1406                 close(fromCgi.rd);
1407                 close(toCgi.wr);
1408                 /* User seeing stderr output can be a security problem.
1409                  * If CGI really wants that, it can always do dup itself. */
1410                 /* dup2(1, 2); */
1411
1412                 /* script must have absolute path */
1413                 script = strrchr(fullpath, '/');
1414                 if (!script)
1415                         goto error_execing_cgi;
1416                 *script = '\0';
1417                 /* chdiring to script's dir */
1418                 if (chdir(fullpath) == 0) {
1419                         char *argv[2];
1420 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1421                         char *interpr = NULL;
1422                         char *suffix = strrchr(purl, '.');
1423
1424                         if (suffix) {
1425                                 Htaccess *cur;
1426                                 for (cur = script_i; cur; cur = cur->next) {
1427                                         if (strcmp(cur->before_colon + 1, suffix) == 0) {
1428                                                 interpr = cur->after_colon;
1429                                                 break;
1430                                         }
1431                                 }
1432                         }
1433 #endif
1434                         *script = '/';
1435                         /* set argv[0] to name without path */
1436                         argv[0] = (char*)bb_basename(purl);
1437                         argv[1] = NULL;
1438 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
1439                         if (interpr)
1440                                 execv(interpr, argv);
1441                         else
1442 #endif
1443                                 execv(fullpath, argv);
1444                 }
1445  error_execing_cgi:
1446                 /* send to stdout
1447                  * (we are CGI here, our stdout is pumped to the net) */
1448                 send_headers_and_exit(HTTP_NOT_FOUND);
1449         } /* end child */
1450
1451         /* Parent process */
1452
1453         /* Restore variables possibly changed by child */
1454         xfunc_error_retval = 0;
1455
1456         /* Pump data */
1457         close(fromCgi.wr);
1458         close(toCgi.rd);
1459         cgi_io_loop_and_exit(fromCgi.rd, toCgi.wr, post_len);
1460 }
1461
1462 #endif          /* FEATURE_HTTPD_CGI */
1463
1464 /*
1465  * Send a file response to a HTTP request, and exit
1466  *
1467  * Parameters:
1468  * const char *url    The requested URL (with leading /).
1469  * headers            Don't send headers before if FALSE.
1470  */
1471 static void send_file_and_exit(const char *url, int headers)
1472 {
1473         static const char *const suffixTable[] = {
1474         /* Warning: shorter equivalent suffix in one line must be first */
1475                 ".htm.html", "text/html",
1476                 ".jpg.jpeg", "image/jpeg",
1477                 ".gif",      "image/gif",
1478                 ".png",      "image/png",
1479                 ".txt.h.c.cc.cpp", "text/plain",
1480                 ".css",      "text/css",
1481                 ".wav",      "audio/wav",
1482                 ".avi",      "video/x-msvideo",
1483                 ".qt.mov",   "video/quicktime",
1484                 ".mpe.mpeg", "video/mpeg",
1485                 ".mid.midi", "audio/midi",
1486                 ".mp3",      "audio/mpeg",
1487 #if 0                        /* unpopular */
1488                 ".au",       "audio/basic",
1489                 ".pac",      "application/x-ns-proxy-autoconfig",
1490                 ".vrml.wrl", "model/vrml",
1491 #endif
1492                 NULL
1493         };
1494
1495         char *suffix;
1496         int f;
1497         const char *const *table;
1498         const char *try_suffix;
1499         ssize_t count;
1500 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1501         off_t offset;
1502 #endif
1503
1504         suffix = strrchr(url, '.');
1505
1506         /* If not found, set default as "application/octet-stream";  */
1507         found_mime_type = "application/octet-stream";
1508         if (suffix) {
1509 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1510                 Htaccess *cur;
1511 #endif
1512                 for (table = suffixTable; *table; table += 2) {
1513                         try_suffix = strstr(table[0], suffix);
1514                         if (try_suffix) {
1515                                 try_suffix += strlen(suffix);
1516                                 if (*try_suffix == '\0' || *try_suffix == '.') {
1517                                         found_mime_type = table[1];
1518                                         break;
1519                                 }
1520                         }
1521                 }
1522 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_MIME_TYPES
1523                 for (cur = mime_a; cur; cur = cur->next) {
1524                         if (strcmp(cur->before_colon, suffix) == 0) {
1525                                 found_mime_type = cur->after_colon;
1526                                 break;
1527                         }
1528                 }
1529 #endif
1530         }
1531
1532         if (DEBUG)
1533                 bb_error_msg("sending file '%s' content-type: %s",
1534                         url, found_mime_type);
1535
1536         f = open(url, O_RDONLY);
1537         if (f < 0) {
1538                 if (DEBUG)
1539                         bb_perror_msg("cannot open '%s'", url);
1540                 if (headers)
1541                         send_headers_and_exit(HTTP_NOT_FOUND);
1542         }
1543 #if ENABLE_FEATURE_HTTPD_RANGES
1544         if (!headers)
1545                 range_start = 0; /* err pages and ranges don't mix */
1546         range_len = MAXINT(off_t);
1547         if (range_start) {
1548                 if (!range_end) {
1549                         range_end = file_size - 1;
1550                 }
1551                 if (range_end < range_start
1552                  || lseek(f, range_start, SEEK_SET) != range_start
1553                 ) {
1554                         lseek(f, 0, SEEK_SET);
1555                         range_start = 0;
1556                 } else {
1557                         range_len = range_end - range_start + 1;
1558                         send_headers(HTTP_PARTIAL_CONTENT);
1559                         headers = 0;
1560                 }
1561         }
1562 #endif
1563
1564         if (headers)
1565                 send_headers(HTTP_OK);
1566
1567         /* If you want to know about EPIPE below
1568          * (happens if you abort downloads from local httpd): */
1569         signal(SIGPIPE, SIG_IGN);
1570
1571 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1572         offset = range_start;
1573         do {
1574                 /* sz is rounded down to 64k */
1575                 ssize_t sz = MAXINT(ssize_t) - 0xffff;
1576                 USE_FEATURE_HTTPD_RANGES(if (sz > range_len) sz = range_len;)
1577                 count = sendfile(1, f, &offset, sz);
1578                 if (count < 0) {
1579                         if (offset == range_start)
1580                                 goto fallback;
1581                         goto fin;
1582                 }
1583                 USE_FEATURE_HTTPD_RANGES(range_len -= sz;)
1584         } while (count > 0 && range_len);
1585         log_and_exit();
1586
1587  fallback:
1588 #endif
1589         while ((count = safe_read(f, iobuf, IOBUF_SIZE)) > 0) {
1590                 ssize_t n;
1591                 USE_FEATURE_HTTPD_RANGES(if (count > range_len) count = range_len;)
1592                 n = full_write(1, iobuf, count);
1593                 if (count != n)
1594                         break;
1595                 USE_FEATURE_HTTPD_RANGES(range_len -= count;)
1596                 if (!range_len)
1597                         break;
1598         }
1599 #if ENABLE_FEATURE_HTTPD_USE_SENDFILE
1600  fin:
1601 #endif
1602         if (count < 0 && verbose > 1)
1603                 bb_perror_msg("error");
1604         log_and_exit();
1605 }
1606
1607 static int checkPermIP(void)
1608 {
1609         Htaccess_IP *cur;
1610
1611         /* This could stand some work */
1612         for (cur = ip_a_d; cur; cur = cur->next) {
1613 #if DEBUG
1614                 fprintf(stderr,
1615                         "checkPermIP: '%s' ? '%u.%u.%u.%u/%u.%u.%u.%u'\n",
1616                         rmt_ip_str,
1617                         (unsigned char)(cur->ip >> 24),
1618                         (unsigned char)(cur->ip >> 16),
1619                         (unsigned char)(cur->ip >> 8),
1620                         (unsigned char)(cur->ip),
1621                         (unsigned char)(cur->mask >> 24),
1622                         (unsigned char)(cur->mask >> 16),
1623                         (unsigned char)(cur->mask >> 8),
1624                         (unsigned char)(cur->mask)
1625                 );
1626 #endif
1627                 if ((rmt_ip & cur->mask) == cur->ip)
1628                         return cur->allow_deny == 'A';   /* Allow/Deny */
1629         }
1630
1631         /* if unconfigured, return 1 - access from all */
1632         return !flg_deny_all;
1633 }
1634
1635 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1636 /*
1637  * Check the permission file for access password protected.
1638  *
1639  * If config file isn't present, everything is allowed.
1640  * Entries are of the form you can see example from header source
1641  *
1642  * path      The file path.
1643  * request   User information to validate.
1644  *
1645  * Returns 1 if request is OK.
1646  */
1647 static int checkPerm(const char *path, const char *request)
1648 {
1649         Htaccess *cur;
1650         const char *p;
1651         const char *p0;
1652
1653         const char *prev = NULL;
1654
1655         /* This could stand some work */
1656         for (cur = g_auth; cur; cur = cur->next) {
1657                 size_t l;
1658
1659                 p0 = cur->before_colon;
1660                 if (prev != NULL && strcmp(prev, p0) != 0)
1661                         continue;       /* find next identical */
1662                 p = cur->after_colon;
1663                 if (DEBUG)
1664                         fprintf(stderr, "checkPerm: '%s' ? '%s'\n", p0, request);
1665
1666                 l = strlen(p0);
1667                 if (strncmp(p0, path, l) == 0
1668                  && (l == 1 || path[l] == '/' || path[l] == '\0')
1669                 ) {
1670                         char *u;
1671                         /* path match found.  Check request */
1672                         /* for check next /path:user:password */
1673                         prev = p0;
1674                         u = strchr(request, ':');
1675                         if (u == NULL) {
1676                                 /* bad request, ':' required */
1677                                 break;
1678                         }
1679
1680                         if (ENABLE_FEATURE_HTTPD_AUTH_MD5) {
1681                                 char *cipher;
1682                                 char *pp;
1683
1684                                 if (strncmp(p, request, u - request) != 0) {
1685                                         /* user doesn't match */
1686                                         continue;
1687                                 }
1688                                 pp = strchr(p, ':');
1689                                 if (pp && pp[1] == '$' && pp[2] == '1'
1690                                  && pp[3] == '$' && pp[4]
1691                                 ) {
1692                                         pp++;
1693                                         cipher = pw_encrypt(u+1, pp);
1694                                         if (strcmp(cipher, pp) == 0)
1695                                                 goto set_remoteuser_var;   /* Ok */
1696                                         /* unauthorized */
1697                                         continue;
1698                                 }
1699                         }
1700
1701                         if (strcmp(p, request) == 0) {
1702  set_remoteuser_var:
1703                                 remoteuser = strdup(request);
1704                                 if (remoteuser)
1705                                         remoteuser[u - request] = '\0';
1706                                 return 1;   /* Ok */
1707                         }
1708                         /* unauthorized */
1709                 }
1710         } /* for */
1711
1712         return prev == NULL;
1713 }
1714 #endif  /* FEATURE_HTTPD_BASIC_AUTH */
1715
1716 #if ENABLE_FEATURE_HTTPD_PROXY
1717 static Htaccess_Proxy *find_proxy_entry(const char *url)
1718 {
1719         Htaccess_Proxy *p;
1720         for (p = proxy; p; p = p->next) {
1721                 if (strncmp(url, p->url_from, strlen(p->url_from)) == 0)
1722                         return p;
1723         }
1724         return NULL;
1725 }
1726 #endif
1727
1728 /*
1729  * Handle timeouts
1730  */
1731 static void exit_on_signal(int sig) ATTRIBUTE_NORETURN;
1732 static void exit_on_signal(int sig)
1733 {
1734         send_headers_and_exit(HTTP_REQUEST_TIMEOUT);
1735 }
1736
1737 /*
1738  * Handle an incoming http request and exit.
1739  */
1740 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) ATTRIBUTE_NORETURN;
1741 static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr)
1742 {
1743         static const char request_GET[] ALIGN1 = "GET";
1744
1745         struct stat sb;
1746         char *urlcopy;
1747         char *urlp;
1748         char *tptr;
1749         int ip_allowed;
1750 #if ENABLE_FEATURE_HTTPD_CGI
1751         const char *prequest;
1752         char *cookie = NULL;
1753         char *content_type = NULL;
1754         unsigned long length = 0;
1755 #elif ENABLE_FEATURE_HTTPD_PROXY
1756 #define prequest request_GET
1757         unsigned long length = 0;
1758 #endif
1759         char http_major_version;
1760 #if ENABLE_FEATURE_HTTPD_PROXY
1761         char http_minor_version;
1762         char *header_buf = header_buf; /* for gcc */
1763         char *header_ptr = header_ptr;
1764         Htaccess_Proxy *proxy_entry;
1765 #endif
1766         struct sigaction sa;
1767 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1768         int credentials = -1;  /* if not required this is Ok */
1769 #endif
1770
1771         /* Allocation of iobuf is postponed until now
1772          * (IOW, server process doesn't need to waste 8k) */
1773         iobuf = xmalloc(IOBUF_SIZE);
1774
1775         rmt_ip = 0;
1776         if (fromAddr->sa.sa_family == AF_INET) {
1777                 rmt_ip = ntohl(fromAddr->sin.sin_addr.s_addr);
1778         }
1779 #if ENABLE_FEATURE_IPV6
1780         if (fromAddr->sa.sa_family == AF_INET6
1781          && fromAddr->sin6.sin6_addr.s6_addr32[0] == 0
1782          && fromAddr->sin6.sin6_addr.s6_addr32[1] == 0
1783          && ntohl(fromAddr->sin6.sin6_addr.s6_addr32[2]) == 0xffff)
1784                 rmt_ip = ntohl(fromAddr->sin6.sin6_addr.s6_addr32[3]);
1785 #endif
1786         if (ENABLE_FEATURE_HTTPD_CGI || DEBUG || verbose) {
1787                 rmt_ip_str = xmalloc_sockaddr2dotted(&fromAddr->sa);
1788         }
1789         if (verbose) {
1790                 /* this trick makes -v logging much simpler */
1791                 applet_name = rmt_ip_str;
1792                 if (verbose > 2)
1793                         bb_error_msg("connected");
1794         }
1795
1796         /* Install timeout handler */
1797         memset(&sa, 0, sizeof(sa));
1798         sa.sa_handler = exit_on_signal;
1799         /* sigemptyset(&sa.sa_mask); - memset should be enough */
1800         /*sa.sa_flags = 0; - no SA_RESTART */
1801         sigaction(SIGALRM, &sa, NULL);
1802         alarm(HEADER_READ_TIMEOUT);
1803
1804         if (!get_line()) /* EOF or error or empty line */
1805                 send_headers_and_exit(HTTP_BAD_REQUEST);
1806
1807         /* Determine type of request (GET/POST) */
1808         urlp = strpbrk(iobuf, " \t");
1809         if (urlp == NULL)
1810                 send_headers_and_exit(HTTP_BAD_REQUEST);
1811         *urlp++ = '\0';
1812 #if ENABLE_FEATURE_HTTPD_CGI
1813         prequest = request_GET;
1814         if (strcasecmp(iobuf, prequest) != 0) {
1815                 prequest = "POST";
1816                 if (strcasecmp(iobuf, prequest) != 0)
1817                         send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1818         }
1819 #else
1820         if (strcasecmp(iobuf, request_GET) != 0)
1821                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
1822 #endif
1823         urlp = skip_whitespace(urlp);
1824         if (urlp[0] != '/')
1825                 send_headers_and_exit(HTTP_BAD_REQUEST);
1826
1827         /* Find end of URL and parse HTTP version, if any */
1828         http_major_version = '0';
1829         USE_FEATURE_HTTPD_PROXY(http_minor_version = '0';)
1830         tptr = strchrnul(urlp, ' ');
1831         /* Is it " HTTP/"? */
1832         if (tptr[0] && strncmp(tptr + 1, HTTP_200, 5) == 0) {
1833                 http_major_version = tptr[6];
1834                 USE_FEATURE_HTTPD_PROXY(http_minor_version = tptr[8];)
1835         }
1836         *tptr = '\0';
1837
1838         /* Copy URL from after "GET "/"POST " to stack-allocated char[] */
1839         urlcopy = alloca((tptr - urlp) + sizeof("/index.html"));
1840         /*if (urlcopy == NULL)
1841          *      send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);*/
1842         strcpy(urlcopy, urlp);
1843         /* NB: urlcopy ptr is never changed after this */
1844
1845         /* Extract url args if present */
1846         g_query = NULL;
1847         tptr = strchr(urlcopy, '?');
1848         if (tptr) {
1849                 *tptr++ = '\0';
1850                 g_query = tptr;
1851         }
1852
1853         /* Decode URL escape sequences */
1854         tptr = decodeString(urlcopy, 0);
1855         if (tptr == NULL)
1856                 send_headers_and_exit(HTTP_BAD_REQUEST);
1857         if (tptr == urlcopy + 1) {
1858                 /* '/' or NUL is encoded */
1859                 send_headers_and_exit(HTTP_NOT_FOUND);
1860         }
1861
1862         /* Canonicalize path */
1863         /* Algorithm stolen from libbb bb_simplify_path(),
1864          * but don't strdup and reducing trailing slash and protect out root */
1865         urlp = tptr = urlcopy;
1866         do {
1867                 if (*urlp == '/') {
1868                         /* skip duplicate (or initial) slash */
1869                         if (*tptr == '/') {
1870                                 continue;
1871                         }
1872                         if (*tptr == '.') {
1873                                 /* skip extra '.' */
1874                                 if (tptr[1] == '/' || !tptr[1]) {
1875                                         continue;
1876                                 }
1877                                 /* '..': be careful */
1878                                 if (tptr[1] == '.' && (tptr[2] == '/' || !tptr[2])) {
1879                                         ++tptr;
1880                                         if (urlp == urlcopy) /* protect root */
1881                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1882                                         while (*--urlp != '/') /* omit previous dir */;
1883                                                 continue;
1884                                 }
1885                         }
1886                 }
1887                 *++urlp = *tptr;
1888         } while (*++tptr);
1889         *++urlp = '\0';       /* so keep last character */
1890         tptr = urlp;          /* end ptr */
1891
1892         /* If URL is a directory, add '/' */
1893         if (tptr[-1] != '/') {
1894                 if (is_directory(urlcopy + 1, 1, &sb)) {
1895                         found_moved_temporarily = urlcopy;
1896                 }
1897         }
1898
1899         /* Log it */
1900         if (verbose > 1)
1901                 bb_error_msg("url:%s", urlcopy);
1902
1903         tptr = urlcopy;
1904         ip_allowed = checkPermIP();
1905         while (ip_allowed && (tptr = strchr(tptr + 1, '/')) != NULL) {
1906                 /* have path1/path2 */
1907                 *tptr = '\0';
1908                 if (is_directory(urlcopy + 1, 1, &sb)) {
1909                         /* may be having subdir config */
1910                         parse_conf(urlcopy + 1, SUBDIR_PARSE);
1911                         ip_allowed = checkPermIP();
1912                 }
1913                 *tptr = '/';
1914         }
1915
1916 #if ENABLE_FEATURE_HTTPD_PROXY
1917         proxy_entry = find_proxy_entry(urlcopy);
1918         if (proxy_entry)
1919                 header_buf = header_ptr = xmalloc(IOBUF_SIZE);
1920 #endif
1921
1922         if (http_major_version >= '0') {
1923                 /* Request was with "... HTTP/nXXX", and n >= 0 */
1924
1925                 /* Read until blank line for HTTP version specified, else parse immediate */
1926                 while (1) {
1927                         alarm(HEADER_READ_TIMEOUT);
1928                         if (!get_line())
1929                                 break; /* EOF or error or empty line */
1930                         if (DEBUG)
1931                                 bb_error_msg("header: '%s'", iobuf);
1932
1933 #if ENABLE_FEATURE_HTTPD_PROXY
1934                         /* We need 2 more bytes for yet another "\r\n" -
1935                          * see near fdprintf(proxy_fd...) further below */
1936                         if (proxy_entry && (header_ptr - header_buf) < IOBUF_SIZE - 2) {
1937                                 int len = strlen(iobuf);
1938                                 if (len > IOBUF_SIZE - (header_ptr - header_buf) - 4)
1939                                         len = IOBUF_SIZE - (header_ptr - header_buf) - 4;
1940                                 memcpy(header_ptr, iobuf, len);
1941                                 header_ptr += len;
1942                                 header_ptr[0] = '\r';
1943                                 header_ptr[1] = '\n';
1944                                 header_ptr += 2;
1945                         }
1946 #endif
1947
1948 #if ENABLE_FEATURE_HTTPD_CGI || ENABLE_FEATURE_HTTPD_PROXY
1949                         /* Try and do our best to parse more lines */
1950                         if ((STRNCASECMP(iobuf, "Content-length:") == 0)) {
1951                                 /* extra read only for POST */
1952                                 if (prequest != request_GET) {
1953                                         tptr = iobuf + sizeof("Content-length:") - 1;
1954                                         if (!tptr[0])
1955                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1956                                         errno = 0;
1957                                         /* not using strtoul: it ignores leading minus! */
1958                                         length = strtol(tptr, &tptr, 10);
1959                                         /* length is "ulong", but we need to pass it to int later */
1960                                         /* so we check for negative or too large values in one go: */
1961                                         /* (long -> ulong conv caused negatives to be seen as > INT_MAX) */
1962                                         if (tptr[0] || errno || length > INT_MAX)
1963                                                 send_headers_and_exit(HTTP_BAD_REQUEST);
1964                                 }
1965                         }
1966 #endif
1967 #if ENABLE_FEATURE_HTTPD_CGI
1968                         else if (STRNCASECMP(iobuf, "Cookie:") == 0) {
1969                                 cookie = strdup(skip_whitespace(iobuf + sizeof("Cookie:")-1));
1970                         } else if (STRNCASECMP(iobuf, "Content-Type:") == 0) {
1971                                 content_type = strdup(skip_whitespace(iobuf + sizeof("Content-Type:")-1));
1972                         } else if (STRNCASECMP(iobuf, "Referer:") == 0) {
1973                                 referer = strdup(skip_whitespace(iobuf + sizeof("Referer:")-1));
1974                         } else if (STRNCASECMP(iobuf, "User-Agent:") == 0) {
1975                                 user_agent = strdup(skip_whitespace(iobuf + sizeof("User-Agent:")-1));
1976                         }
1977 #endif
1978 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
1979                         if (STRNCASECMP(iobuf, "Authorization:") == 0) {
1980                                 /* We only allow Basic credentials.
1981                                  * It shows up as "Authorization: Basic <userid:password>" where
1982                                  * the userid:password is base64 encoded.
1983                                  */
1984                                 tptr = skip_whitespace(iobuf + sizeof("Authorization:")-1);
1985                                 if (STRNCASECMP(tptr, "Basic") != 0)
1986                                         continue;
1987                                 tptr += sizeof("Basic")-1;
1988                                 /* decodeBase64() skips whitespace itself */
1989                                 decodeBase64(tptr);
1990                                 credentials = checkPerm(urlcopy, tptr);
1991                         }
1992 #endif          /* FEATURE_HTTPD_BASIC_AUTH */
1993 #if ENABLE_FEATURE_HTTPD_RANGES
1994                         if (STRNCASECMP(iobuf, "Range:") == 0) {
1995                                 /* We know only bytes=NNN-[MMM] */
1996                                 char *s = skip_whitespace(iobuf + sizeof("Range:")-1);
1997                                 if (strncmp(s, "bytes=", 6) == 0) {
1998                                         s += sizeof("bytes=")-1;
1999                                         range_start = BB_STRTOOFF(s, &s, 10);
2000                                         if (s[0] != '-' || range_start < 0) {
2001                                                 range_start = 0;
2002                                         } else if (s[1]) {
2003                                                 range_end = BB_STRTOOFF(s+1, NULL, 10);
2004                                                 if (errno || range_end < range_start)
2005                                                         range_start = 0;
2006                                         }
2007                                 }
2008                         }
2009 #endif
2010                 } /* while extra header reading */
2011         }
2012
2013         /* We are done reading headers, disable peer timeout */
2014         alarm(0);
2015
2016         if (strcmp(bb_basename(urlcopy), httpd_conf) == 0 || ip_allowed == 0) {
2017                 /* protect listing [/path]/httpd_conf or IP deny */
2018                 send_headers_and_exit(HTTP_FORBIDDEN);
2019         }
2020
2021 #if ENABLE_FEATURE_HTTPD_BASIC_AUTH
2022         if (credentials <= 0 && checkPerm(urlcopy, ":") == 0) {
2023                 send_headers_and_exit(HTTP_UNAUTHORIZED);
2024         }
2025 #endif
2026
2027         if (found_moved_temporarily) {
2028                 send_headers_and_exit(HTTP_MOVED_TEMPORARILY);
2029         }
2030
2031 #if ENABLE_FEATURE_HTTPD_PROXY
2032         if (proxy_entry != NULL) {
2033                 int proxy_fd;
2034                 len_and_sockaddr *lsa;
2035
2036                 proxy_fd = socket(AF_INET, SOCK_STREAM, 0);
2037                 if (proxy_fd < 0)
2038                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2039                 lsa = host2sockaddr(proxy_entry->host_port, 80);
2040                 if (lsa == NULL)
2041                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2042                 if (connect(proxy_fd, &lsa->sa, lsa->len) < 0)
2043                         send_headers_and_exit(HTTP_INTERNAL_SERVER_ERROR);
2044                 fdprintf(proxy_fd, "%s %s%s%s%s HTTP/%c.%c\r\n",
2045                                 prequest, /* GET or POST */
2046                                 proxy_entry->url_to, /* url part 1 */
2047                                 urlcopy + strlen(proxy_entry->url_from), /* url part 2 */
2048                                 (g_query ? "?" : ""), /* "?" (maybe) */
2049                                 (g_query ? g_query : ""), /* query string (maybe) */
2050                                 http_major_version, http_minor_version);
2051                 header_ptr[0] = '\r';
2052                 header_ptr[1] = '\n';
2053                 header_ptr += 2;
2054                 write(proxy_fd, header_buf, header_ptr - header_buf);
2055                 free(header_buf); /* on the order of 8k, free it */
2056                 /* cgi_io_loop_and_exit needs to have two disctinct fds */
2057                 cgi_io_loop_and_exit(proxy_fd, dup(proxy_fd), length);
2058         }
2059 #endif
2060
2061         tptr = urlcopy + 1;      /* skip first '/' */
2062
2063 #if ENABLE_FEATURE_HTTPD_CGI
2064         if (strncmp(tptr, "cgi-bin/", 8) == 0) {
2065                 if (tptr[8] == '\0') {
2066                         /* protect listing "cgi-bin/" */
2067                         send_headers_and_exit(HTTP_FORBIDDEN);
2068                 }
2069                 send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2070         }
2071 #if ENABLE_FEATURE_HTTPD_CONFIG_WITH_SCRIPT_INTERPR
2072         {
2073                 char *suffix = strrchr(tptr, '.');
2074                 if (suffix) {
2075                         Htaccess *cur;
2076                         for (cur = script_i; cur; cur = cur->next) {
2077                                 if (strcmp(cur->before_colon + 1, suffix) == 0) {
2078                                         send_cgi_and_exit(urlcopy, prequest, length, cookie, content_type);
2079                                 }
2080                         }
2081                 }
2082         }
2083 #endif
2084         if (prequest != request_GET) {
2085                 send_headers_and_exit(HTTP_NOT_IMPLEMENTED);
2086         }
2087 #endif  /* FEATURE_HTTPD_CGI */
2088
2089         if (urlp[-1] == '/')
2090                 strcpy(urlp, "index.html");
2091         if (stat(tptr, &sb) == 0) {
2092                 file_size = sb.st_size;
2093                 last_mod = sb.st_mtime;
2094         }
2095 #if ENABLE_FEATURE_HTTPD_CGI
2096         else if (urlp[-1] == '/') {
2097                 /* It's a dir URL and there is no index.html
2098                  * Try cgi-bin/index.cgi */
2099                 if (access("/cgi-bin/index.cgi"+1, X_OK) == 0) {
2100                         urlp[0] = '\0';
2101                         g_query = urlcopy;
2102                         send_cgi_and_exit("/cgi-bin/index.cgi", prequest, length, cookie, content_type);
2103                 }
2104         }
2105 #endif
2106         /* else {
2107          *      fall through to send_file, it errors out if open fails
2108          * }
2109          */
2110
2111         send_file_and_exit(tptr, TRUE);
2112 }
2113
2114 /*
2115  * The main http server function.
2116  * Given a socket, listen for new connections and farm out
2117  * the processing as a [v]forked process.
2118  * Never returns.
2119  */
2120 #if BB_MMU
2121 static void mini_httpd(int server_socket) ATTRIBUTE_NORETURN;
2122 static void mini_httpd(int server_socket)
2123 {
2124         /* NB: it's best to not use xfuncs in this loop before fork().
2125          * Otherwise server may die on transient errors (temporary
2126          * out-of-memory condition, etc), which is Bad(tm).
2127          * Try to do any dangerous calls after fork.
2128          */
2129         while (1) {
2130                 int n;
2131                 len_and_sockaddr fromAddr;
2132
2133                 /* Wait for connections... */
2134                 fromAddr.len = LSA_SIZEOF_SA;
2135                 n = accept(server_socket, &fromAddr.sa, &fromAddr.len);
2136
2137                 if (n < 0)
2138                         continue;
2139                 /* set the KEEPALIVE option to cull dead connections */
2140                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2141
2142                 if (fork() == 0) {
2143                         /* child */
2144 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2145                         /* Do not reload config on HUP */
2146                         signal(SIGHUP, SIG_IGN);
2147 #endif
2148                         close(server_socket);
2149                         xmove_fd(n, 0);
2150                         xdup2(0, 1);
2151
2152                         handle_incoming_and_exit(&fromAddr);
2153                 }
2154                 /* parent, or fork failed */
2155                 close(n);
2156         } /* while (1) */
2157         /* never reached */
2158 }
2159 #else
2160 static void mini_httpd_nommu(int server_socket, int argc, char **argv) ATTRIBUTE_NORETURN;
2161 static void mini_httpd_nommu(int server_socket, int argc, char **argv)
2162 {
2163         char *argv_copy[argc + 2];
2164
2165         argv_copy[0] = argv[0];
2166         argv_copy[1] = (char*)"-i";
2167         memcpy(&argv_copy[2], &argv[1], argc * sizeof(argv[0]));
2168
2169         /* NB: it's best to not use xfuncs in this loop before vfork().
2170          * Otherwise server may die on transient errors (temporary
2171          * out-of-memory condition, etc), which is Bad(tm).
2172          * Try to do any dangerous calls after fork.
2173          */
2174         while (1) {
2175                 int n;
2176                 len_and_sockaddr fromAddr;
2177
2178                 /* Wait for connections... */
2179                 fromAddr.len = LSA_SIZEOF_SA;
2180                 n = accept(server_socket, &fromAddr.sa, &fromAddr.len);
2181
2182                 if (n < 0)
2183                         continue;
2184                 /* set the KEEPALIVE option to cull dead connections */
2185                 setsockopt(n, SOL_SOCKET, SO_KEEPALIVE, &const_int_1, sizeof(const_int_1));
2186
2187                 if (vfork() == 0) {
2188                         /* child */
2189 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2190                         /* Do not reload config on HUP */
2191                         signal(SIGHUP, SIG_IGN);
2192 #endif
2193                         close(server_socket);
2194                         xmove_fd(n, 0);
2195                         xdup2(0, 1);
2196
2197                         /* Run a copy of ourself in inetd mode */
2198                         re_exec(argv_copy);
2199                 }
2200                 /* parent, or vfork failed */
2201                 close(n);
2202         } /* while (1) */
2203         /* never reached */
2204 }
2205 #endif
2206
2207 /*
2208  * Process a HTTP connection on stdin/out.
2209  * Never returns.
2210  */
2211 static void mini_httpd_inetd(void) ATTRIBUTE_NORETURN;
2212 static void mini_httpd_inetd(void)
2213 {
2214         len_and_sockaddr fromAddr;
2215
2216         fromAddr.len = LSA_SIZEOF_SA;
2217         getpeername(0, &fromAddr.sa, &fromAddr.len);
2218         handle_incoming_and_exit(&fromAddr);
2219 }
2220
2221 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2222 static void sighup_handler(int sig)
2223 {
2224         struct sigaction sa;
2225
2226         parse_conf(default_path_httpd_conf, sig == SIGHUP ? SIGNALED_PARSE : FIRST_PARSE);
2227
2228         memset(&sa, 0, sizeof(sa));
2229         sa.sa_handler = sighup_handler;
2230         /*sigemptyset(&sa.sa_mask); - memset should be enough */
2231         sa.sa_flags = SA_RESTART;
2232         sigaction(SIGHUP, &sa, NULL);
2233 }
2234 #endif
2235
2236 enum {
2237         c_opt_config_file = 0,
2238         d_opt_decode_url,
2239         h_opt_home_httpd,
2240         USE_FEATURE_HTTPD_ENCODE_URL_STR(e_opt_encode_url,)
2241         USE_FEATURE_HTTPD_BASIC_AUTH(    r_opt_realm     ,)
2242         USE_FEATURE_HTTPD_AUTH_MD5(      m_opt_md5       ,)
2243         USE_FEATURE_HTTPD_SETUID(        u_opt_setuid    ,)
2244         p_opt_port      ,
2245         p_opt_inetd     ,
2246         p_opt_foreground,
2247         p_opt_verbose   ,
2248         OPT_CONFIG_FILE = 1 << c_opt_config_file,
2249         OPT_DECODE_URL  = 1 << d_opt_decode_url,
2250         OPT_HOME_HTTPD  = 1 << h_opt_home_httpd,
2251         OPT_ENCODE_URL  = USE_FEATURE_HTTPD_ENCODE_URL_STR((1 << e_opt_encode_url)) + 0,
2252         OPT_REALM       = USE_FEATURE_HTTPD_BASIC_AUTH(    (1 << r_opt_realm     )) + 0,
2253         OPT_MD5         = USE_FEATURE_HTTPD_AUTH_MD5(      (1 << m_opt_md5       )) + 0,
2254         OPT_SETUID      = USE_FEATURE_HTTPD_SETUID(        (1 << u_opt_setuid    )) + 0,
2255         OPT_PORT        = 1 << p_opt_port,
2256         OPT_INETD       = 1 << p_opt_inetd,
2257         OPT_FOREGROUND  = 1 << p_opt_foreground,
2258         OPT_VERBOSE     = 1 << p_opt_verbose,
2259 };
2260
2261
2262 int httpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2263 int httpd_main(int argc, char **argv)
2264 {
2265         int server_socket = server_socket; /* for gcc */
2266         unsigned opt;
2267         char *url_for_decode;
2268         USE_FEATURE_HTTPD_ENCODE_URL_STR(const char *url_for_encode;)
2269         USE_FEATURE_HTTPD_SETUID(const char *s_ugid = NULL;)
2270         USE_FEATURE_HTTPD_SETUID(struct bb_uidgid_t ugid;)
2271         USE_FEATURE_HTTPD_AUTH_MD5(const char *pass;)
2272
2273         INIT_G();
2274
2275 #if ENABLE_LOCALE_SUPPORT
2276         /* Undo busybox.c: we want to speak English in http (dates etc) */
2277         setlocale(LC_TIME, "C");
2278 #endif
2279
2280         home_httpd = xrealloc_getcwd_or_warn(NULL);
2281         /* -v counts, -i implies -f */
2282         opt_complementary = "vv:if";
2283         /* We do not "absolutize" path given by -h (home) opt.
2284          * If user gives relative path in -h, $SCRIPT_FILENAME can end up
2285          * relative too. */
2286         opt = getopt32(argv, "c:d:h:"
2287                         USE_FEATURE_HTTPD_ENCODE_URL_STR("e:")
2288                         USE_FEATURE_HTTPD_BASIC_AUTH("r:")
2289                         USE_FEATURE_HTTPD_AUTH_MD5("m:")
2290                         USE_FEATURE_HTTPD_SETUID("u:")
2291                         "p:ifv",
2292                         &configFile, &url_for_decode, &home_httpd
2293                         USE_FEATURE_HTTPD_ENCODE_URL_STR(, &url_for_encode)
2294                         USE_FEATURE_HTTPD_BASIC_AUTH(, &g_realm)
2295                         USE_FEATURE_HTTPD_AUTH_MD5(, &pass)
2296                         USE_FEATURE_HTTPD_SETUID(, &s_ugid)
2297                         , &bind_addr_or_port
2298                         , &verbose
2299                 );
2300         if (opt & OPT_DECODE_URL) {
2301                 fputs(decodeString(url_for_decode, 1), stdout);
2302                 return 0;
2303         }
2304 #if ENABLE_FEATURE_HTTPD_ENCODE_URL_STR
2305         if (opt & OPT_ENCODE_URL) {
2306                 fputs(encodeString(url_for_encode), stdout);
2307                 return 0;
2308         }
2309 #endif
2310 #if ENABLE_FEATURE_HTTPD_AUTH_MD5
2311         if (opt & OPT_MD5) {
2312                 puts(pw_encrypt(pass, "$1$"));
2313                 return 0;
2314         }
2315 #endif
2316 #if ENABLE_FEATURE_HTTPD_SETUID
2317         if (opt & OPT_SETUID) {
2318                 if (!get_uidgid(&ugid, s_ugid, 1))
2319                         bb_error_msg_and_die("unrecognized user[:group] "
2320                                                 "name '%s'", s_ugid);
2321         }
2322 #endif
2323
2324 #if !BB_MMU
2325         if (!(opt & OPT_FOREGROUND)) {
2326                 bb_daemonize_or_rexec(0, argv); /* don't change current directory */
2327         }
2328 #endif
2329
2330         xchdir(home_httpd);
2331         if (!(opt & OPT_INETD)) {
2332                 signal(SIGCHLD, SIG_IGN);
2333                 server_socket = openServer();
2334 #if ENABLE_FEATURE_HTTPD_SETUID
2335                 /* drop privileges */
2336                 if (opt & OPT_SETUID) {
2337                         if (ugid.gid != (gid_t)-1) {
2338                                 if (setgroups(1, &ugid.gid) == -1)
2339                                         bb_perror_msg_and_die("setgroups");
2340                                 xsetgid(ugid.gid);
2341                         }
2342                         xsetuid(ugid.uid);
2343                 }
2344 #endif
2345         }
2346
2347 #if 0 /*was #if ENABLE_FEATURE_HTTPD_CGI*/
2348         /* User can do it himself: 'env - PATH="$PATH" httpd'
2349          * We don't do it because we don't want to screw users
2350          * which want to do
2351          * 'env - VAR1=val1 VAR2=val2 httpd'
2352          * and have VAR1 and VAR2 values visible in their CGIs.
2353          * Besides, it is also smaller. */
2354         {
2355                 char *p = getenv("PATH");
2356                 /* env strings themself are not freed, no need to strdup(p): */
2357                 clearenv();
2358                 if (p)
2359                         putenv(p - 5);
2360 //              if (!(opt & OPT_INETD))
2361 //                      setenv_long("SERVER_PORT", ???);
2362         }
2363 #endif
2364
2365 #if ENABLE_FEATURE_HTTPD_RELOAD_CONFIG_SIGHUP
2366         if (!(opt & OPT_INETD))
2367                 sighup_handler(0);
2368         else /* do not install HUP handler in inetd mode */
2369 #endif
2370                 parse_conf(default_path_httpd_conf, FIRST_PARSE);
2371
2372         xfunc_error_retval = 0;
2373         if (opt & OPT_INETD)
2374                 mini_httpd_inetd();
2375 #if BB_MMU
2376         if (!(opt & OPT_FOREGROUND))
2377                 bb_daemonize(0); /* don't change current directory */
2378         mini_httpd(server_socket); /* never returns */
2379 #else
2380         mini_httpd_nommu(server_socket, argc, argv); /* never returns */
2381 #endif
2382         /* return 0; */
2383 }