[package] uhttpd:
[openwrt/svn-archive/archive.git] / package / uhttpd / src / uhttpd-utils.c
1 /*
2 * uhttpd - Tiny single-threaded httpd - Utility functions
3 *
4 * Copyright (C) 2010 Jo-Philipp Wich <xm@subsignal.org>
5 *
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19 #define _XOPEN_SOURCE 500 /* crypt() */
20 #define _BSD_SOURCE /* strcasecmp(), strncasecmp() */
21
22 #include "uhttpd.h"
23 #include "uhttpd-utils.h"
24
25 #ifdef HAVE_TLS
26 #include "uhttpd-tls.h"
27 #endif
28
29
30 static char *uh_index_files[] = {
31 "index.html",
32 "index.htm",
33 "default.html",
34 "default.htm"
35 };
36
37
38 const char * sa_straddr(void *sa)
39 {
40 static char str[INET6_ADDRSTRLEN];
41 struct sockaddr_in *v4 = (struct sockaddr_in *)sa;
42 struct sockaddr_in6 *v6 = (struct sockaddr_in6 *)sa;
43
44 if( v4->sin_family == AF_INET )
45 return inet_ntop(AF_INET, &(v4->sin_addr), str, sizeof(str));
46 else
47 return inet_ntop(AF_INET6, &(v6->sin6_addr), str, sizeof(str));
48 }
49
50 const char * sa_strport(void *sa)
51 {
52 static char str[6];
53 snprintf(str, sizeof(str), "%i", sa_port(sa));
54 return str;
55 }
56
57 int sa_port(void *sa)
58 {
59 return ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
60 }
61
62 /* Simple strstr() like function that takes len arguments for both haystack and needle. */
63 char *strfind(char *haystack, int hslen, const char *needle, int ndlen)
64 {
65 int match = 0;
66 int i, j;
67
68 for( i = 0; i < hslen; i++ )
69 {
70 if( haystack[i] == needle[0] )
71 {
72 match = ((ndlen == 1) || ((i + ndlen) <= hslen));
73
74 for( j = 1; (j < ndlen) && ((i + j) < hslen); j++ )
75 {
76 if( haystack[i+j] != needle[j] )
77 {
78 match = 0;
79 break;
80 }
81 }
82
83 if( match )
84 return &haystack[i];
85 }
86 }
87
88 return NULL;
89 }
90
91 /* interruptable select() */
92 int select_intr(int n, fd_set *r, fd_set *w, fd_set *e, struct timeval *t)
93 {
94 int rv;
95 sigset_t ssn, sso;
96
97 /* unblock SIGCHLD */
98 sigemptyset(&ssn);
99 sigaddset(&ssn, SIGCHLD);
100 sigprocmask(SIG_UNBLOCK, &ssn, &sso);
101
102 rv = select(n, r, w, e, t);
103
104 /* restore signal mask */
105 sigprocmask(SIG_SETMASK, &sso, NULL);
106
107 return rv;
108 }
109
110
111 int uh_tcp_send(struct client *cl, const char *buf, int len)
112 {
113 fd_set writer;
114 struct timeval timeout;
115
116 FD_ZERO(&writer);
117 FD_SET(cl->socket, &writer);
118
119 timeout.tv_sec = cl->server->conf->network_timeout;
120 timeout.tv_usec = 0;
121
122 if( select(cl->socket + 1, NULL, &writer, NULL, &timeout) > 0 )
123 {
124 #ifdef HAVE_TLS
125 if( cl->tls )
126 return cl->server->conf->tls_send(cl, (void *)buf, len);
127 else
128 #endif
129 return send(cl->socket, buf, len, 0);
130 }
131
132 return -1;
133 }
134
135 int uh_tcp_peek(struct client *cl, char *buf, int len)
136 {
137 int sz = uh_tcp_recv(cl, buf, len);
138
139 /* store received data in peek buffer */
140 if( sz > 0 )
141 {
142 cl->peeklen = sz;
143 memcpy(cl->peekbuf, buf, sz);
144 }
145
146 return sz;
147 }
148
149 int uh_tcp_recv(struct client *cl, char *buf, int len)
150 {
151 int sz = 0;
152 int rsz = 0;
153
154 /* first serve data from peek buffer */
155 if( cl->peeklen > 0 )
156 {
157 sz = min(cl->peeklen, len);
158 len -= sz; cl->peeklen -= sz;
159
160 memcpy(buf, cl->peekbuf, sz);
161 memmove(cl->peekbuf, &cl->peekbuf[sz], cl->peeklen);
162 }
163
164 /* caller wants more */
165 if( len > 0 )
166 {
167 #ifdef HAVE_TLS
168 if( cl->tls )
169 rsz = cl->server->conf->tls_recv(cl, (void *)&buf[sz], len);
170 else
171 #endif
172 rsz = recv(cl->socket, (void *)&buf[sz], len, 0);
173
174 if( (sz == 0) || (rsz > 0) )
175 sz += rsz;
176 }
177
178 return sz;
179 }
180
181 #define ensure(x) \
182 do { if( x < 0 ) return -1; } while(0)
183
184 int uh_http_sendhf(struct client *cl, int code, const char *summary, const char *fmt, ...)
185 {
186 va_list ap;
187
188 char buffer[UH_LIMIT_MSGHEAD];
189 int len;
190
191 len = snprintf(buffer, sizeof(buffer),
192 "HTTP/1.1 %03i %s\r\n"
193 "Connection: close\r\n"
194 "Content-Type: text/plain\r\n"
195 "Transfer-Encoding: chunked\r\n\r\n",
196 code, summary
197 );
198
199 ensure(uh_tcp_send(cl, buffer, len));
200
201 va_start(ap, fmt);
202 len = vsnprintf(buffer, sizeof(buffer), fmt, ap);
203 va_end(ap);
204
205 ensure(uh_http_sendc(cl, buffer, len));
206 ensure(uh_http_sendc(cl, NULL, 0));
207
208 return 0;
209 }
210
211
212 int uh_http_sendc(struct client *cl, const char *data, int len)
213 {
214 char chunk[8];
215 int clen;
216
217 if( len == -1 )
218 len = strlen(data);
219
220 if( len > 0 )
221 {
222 clen = snprintf(chunk, sizeof(chunk), "%X\r\n", len);
223 ensure(uh_tcp_send(cl, chunk, clen));
224 ensure(uh_tcp_send(cl, data, len));
225 ensure(uh_tcp_send(cl, "\r\n", 2));
226 }
227 else
228 {
229 ensure(uh_tcp_send(cl, "0\r\n\r\n", 5));
230 }
231
232 return 0;
233 }
234
235 int uh_http_sendf(
236 struct client *cl, struct http_request *req, const char *fmt, ...
237 ) {
238 va_list ap;
239 char buffer[UH_LIMIT_MSGHEAD];
240 int len;
241
242 va_start(ap, fmt);
243 len = vsnprintf(buffer, sizeof(buffer), fmt, ap);
244 va_end(ap);
245
246 if( (req != NULL) && (req->version > 1.0) )
247 ensure(uh_http_sendc(cl, buffer, len));
248 else if( len > 0 )
249 ensure(uh_tcp_send(cl, buffer, len));
250
251 return 0;
252 }
253
254 int uh_http_send(
255 struct client *cl, struct http_request *req, const char *buf, int len
256 ) {
257 if( len < 0 )
258 len = strlen(buf);
259
260 if( (req != NULL) && (req->version > 1.0) )
261 ensure(uh_http_sendc(cl, buf, len));
262 else if( len > 0 )
263 ensure(uh_tcp_send(cl, buf, len));
264
265 return 0;
266 }
267
268
269 int uh_urldecode(char *buf, int blen, const char *src, int slen)
270 {
271 int i;
272 int len = 0;
273
274 #define hex(x) \
275 (((x) <= '9') ? ((x) - '0') : \
276 (((x) <= 'F') ? ((x) - 'A' + 10) : \
277 ((x) - 'a' + 10)))
278
279 for( i = 0; (i <= slen) && (i <= blen); i++ )
280 {
281 if( src[i] == '%' )
282 {
283 if( ((i+2) <= slen) && isxdigit(src[i+1]) && isxdigit(src[i+2]) )
284 {
285 buf[len++] = (char)(16 * hex(src[i+1]) + hex(src[i+2]));
286 i += 2;
287 }
288 else
289 {
290 buf[len++] = '%';
291 }
292 }
293 else
294 {
295 buf[len++] = src[i];
296 }
297 }
298
299 return len;
300 }
301
302 int uh_urlencode(char *buf, int blen, const char *src, int slen)
303 {
304 int i;
305 int len = 0;
306 const char hex[] = "0123456789abcdef";
307
308 for( i = 0; (i <= slen) && (i <= blen); i++ )
309 {
310 if( isalnum(src[i]) || (src[i] == '-') || (src[i] == '_') ||
311 (src[i] == '.') || (src[i] == '~') )
312 {
313 buf[len++] = src[i];
314 }
315 else if( (len+3) <= blen )
316 {
317 buf[len++] = '%';
318 buf[len++] = hex[(src[i] >> 4) & 15];
319 buf[len++] = hex[(src[i] & 15) & 15];
320 }
321 else
322 {
323 break;
324 }
325 }
326
327 return len;
328 }
329
330 int uh_b64decode(char *buf, int blen, const unsigned char *src, int slen)
331 {
332 int i = 0;
333 int len = 0;
334
335 unsigned int cin = 0;
336 unsigned int cout = 0;
337
338
339 for( i = 0; (i <= slen) && (src[i] != 0); i++ )
340 {
341 cin = src[i];
342
343 if( (cin >= '0') && (cin <= '9') )
344 cin = cin - '0' + 52;
345 else if( (cin >= 'A') && (cin <= 'Z') )
346 cin = cin - 'A';
347 else if( (cin >= 'a') && (cin <= 'z') )
348 cin = cin - 'a' + 26;
349 else if( cin == '+' )
350 cin = 62;
351 else if( cin == '/' )
352 cin = 63;
353 else if( cin == '=' )
354 cin = 0;
355 else
356 continue;
357
358 cout = (cout << 6) | cin;
359
360 if( (i % 4) == 3 )
361 {
362 if( (len + 3) < blen )
363 {
364 buf[len++] = (char)(cout >> 16);
365 buf[len++] = (char)(cout >> 8);
366 buf[len++] = (char)(cout);
367 }
368 else
369 {
370 break;
371 }
372 }
373 }
374
375 buf[len++] = 0;
376 return len;
377 }
378
379 static char * canonpath(const char *path, char *path_resolved)
380 {
381 char path_copy[PATH_MAX];
382 char *path_cpy = path_copy;
383 char *path_res = path_resolved;
384
385 struct stat s;
386
387
388 /* relative -> absolute */
389 if( *path != '/' )
390 {
391 getcwd(path_copy, PATH_MAX);
392 strncat(path_copy, "/", PATH_MAX - strlen(path_copy));
393 strncat(path_copy, path, PATH_MAX - strlen(path_copy));
394 }
395 else
396 {
397 strncpy(path_copy, path, PATH_MAX);
398 }
399
400 /* normalize */
401 while( (*path_cpy != '\0') && (path_cpy < (path_copy + PATH_MAX - 2)) )
402 {
403 if( *path_cpy == '/' )
404 {
405 /* skip repeating / */
406 if( path_cpy[1] == '/' )
407 {
408 path_cpy++;
409 continue;
410 }
411
412 /* /./ or /../ */
413 else if( path_cpy[1] == '.' )
414 {
415 /* skip /./ */
416 if( (path_cpy[2] == '/') || (path_cpy[2] == '\0') )
417 {
418 path_cpy += 2;
419 continue;
420 }
421
422 /* collapse /x/../ */
423 else if( path_cpy[2] == '.' )
424 {
425 while( (path_res > path_resolved) && (*--path_res != '/') )
426 ;
427
428 path_cpy += 3;
429 continue;
430 }
431 }
432 }
433
434 *path_res++ = *path_cpy++;
435 }
436
437 /* remove trailing slash if not root / */
438 if( (path_res > (path_resolved+1)) && (path_res[-1] == '/') )
439 path_res--;
440 else if( path_res == path_resolved )
441 *path_res++ = '/';
442
443 *path_res = '\0';
444
445 /* test access */
446 if( !stat(path_resolved, &s) && (s.st_mode & S_IROTH) )
447 return path_resolved;
448
449 return NULL;
450 }
451
452 struct path_info * uh_path_lookup(struct client *cl, const char *url)
453 {
454 static char path_phys[PATH_MAX];
455 static char path_info[PATH_MAX];
456 static struct path_info p;
457
458 char buffer[UH_LIMIT_MSGHEAD];
459 char *docroot = cl->server->conf->docroot;
460 char *pathptr = NULL;
461
462 int no_sym = cl->server->conf->no_symlinks;
463 int i = 0;
464 struct stat s;
465
466
467 memset(path_phys, 0, sizeof(path_phys));
468 memset(path_info, 0, sizeof(path_info));
469 memset(buffer, 0, sizeof(buffer));
470 memset(&p, 0, sizeof(p));
471
472 /* copy docroot */
473 memcpy(buffer, docroot,
474 min(strlen(docroot), sizeof(buffer) - 1));
475
476 /* separate query string from url */
477 if( (pathptr = strchr(url, '?')) != NULL )
478 {
479 p.query = pathptr[1] ? pathptr + 1 : NULL;
480
481 /* urldecode component w/o query */
482 if( pathptr > url )
483 uh_urldecode(
484 &buffer[strlen(docroot)],
485 sizeof(buffer) - strlen(docroot) - 1,
486 url, (int)(pathptr - url) - 1
487 );
488 }
489
490 /* no query string, decode all of url */
491 else
492 {
493 uh_urldecode(
494 &buffer[strlen(docroot)],
495 sizeof(buffer) - strlen(docroot) - 1,
496 url, strlen(url)
497 );
498 }
499
500 /* create canon path */
501 for( i = strlen(buffer); i >= 0; i-- )
502 {
503 if( (buffer[i] == 0) || (buffer[i] == '/') )
504 {
505 memset(path_info, 0, sizeof(path_info));
506 memcpy(path_info, buffer, min(i + 1, sizeof(path_info) - 1));
507
508 if( no_sym ? realpath(path_info, path_phys)
509 : canonpath(path_info, path_phys)
510 ) {
511 memset(path_info, 0, sizeof(path_info));
512 memcpy(path_info, &buffer[i],
513 min(strlen(buffer) - i, sizeof(path_info) - 1));
514
515 break;
516 }
517 }
518 }
519
520 /* check whether found path is within docroot */
521 if( strncmp(path_phys, docroot, strlen(docroot)) ||
522 ((path_phys[strlen(docroot)] != 0) &&
523 (path_phys[strlen(docroot)] != '/'))
524 ) {
525 return NULL;
526 }
527
528 /* test current path */
529 if( ! stat(path_phys, &p.stat) )
530 {
531 /* is a regular file */
532 if( p.stat.st_mode & S_IFREG )
533 {
534 p.root = docroot;
535 p.phys = path_phys;
536 p.name = &path_phys[strlen(docroot)];
537 p.info = path_info[0] ? path_info : NULL;
538 }
539
540 /* is a directory */
541 else if( (p.stat.st_mode & S_IFDIR) && !strlen(path_info) )
542 {
543 /* ensure trailing slash */
544 if( path_phys[strlen(path_phys)-1] != '/' )
545 path_phys[strlen(path_phys)] = '/';
546
547 /* try to locate index file */
548 memset(buffer, 0, sizeof(buffer));
549 memcpy(buffer, path_phys, sizeof(buffer));
550 pathptr = &buffer[strlen(buffer)];
551
552 for( i = 0; i < array_size(uh_index_files); i++ )
553 {
554 strncat(buffer, uh_index_files[i], sizeof(buffer));
555
556 if( !stat(buffer, &s) && (s.st_mode & S_IFREG) )
557 {
558 memcpy(path_phys, buffer, sizeof(path_phys));
559 memcpy(&p.stat, &s, sizeof(p.stat));
560 break;
561 }
562
563 *pathptr = 0;
564 }
565
566 p.root = docroot;
567 p.phys = path_phys;
568 p.name = &path_phys[strlen(docroot)];
569 }
570 }
571
572 return p.phys ? &p : NULL;
573 }
574
575
576 static char uh_realms[UH_LIMIT_AUTHREALMS * sizeof(struct auth_realm)] = { 0 };
577 static int uh_realm_count = 0;
578
579 struct auth_realm * uh_auth_add(char *path, char *user, char *pass)
580 {
581 struct auth_realm *new = NULL;
582 struct passwd *pwd;
583 struct spwd *spwd;
584
585 if( uh_realm_count < UH_LIMIT_AUTHREALMS )
586 {
587 new = (struct auth_realm *)
588 &uh_realms[uh_realm_count * sizeof(struct auth_realm)];
589
590 memset(new, 0, sizeof(struct auth_realm));
591
592 memcpy(new->path, path,
593 min(strlen(path), sizeof(new->path) - 1));
594
595 memcpy(new->user, user,
596 min(strlen(user), sizeof(new->user) - 1));
597
598 /* given password refers to a passwd entry */
599 if( (strlen(pass) > 3) && !strncmp(pass, "$p$", 3) )
600 {
601 /* try to resolve shadow entry */
602 if( ((spwd = getspnam(&pass[3])) != NULL) && spwd->sp_pwdp )
603 {
604 memcpy(new->pass, spwd->sp_pwdp,
605 min(strlen(spwd->sp_pwdp), sizeof(new->pass) - 1));
606 }
607
608 /* try to resolve passwd entry */
609 else if( ((pwd = getpwnam(&pass[3])) != NULL) && pwd->pw_passwd &&
610 (pwd->pw_passwd[0] != '!') && (pwd->pw_passwd[0] != 0)
611 ) {
612 memcpy(new->pass, pwd->pw_passwd,
613 min(strlen(pwd->pw_passwd), sizeof(new->pass) - 1));
614 }
615 }
616
617 /* ordinary pwd */
618 else
619 {
620 memcpy(new->pass, pass,
621 min(strlen(pass), sizeof(new->pass) - 1));
622 }
623
624 uh_realm_count++;
625 }
626
627 return new;
628 }
629
630 int uh_auth_check(
631 struct client *cl, struct http_request *req, struct path_info *pi
632 ) {
633 int i, plen, rlen, protected;
634 char buffer[UH_LIMIT_MSGHEAD];
635 char *user = NULL;
636 char *pass = NULL;
637
638 struct auth_realm *realm = NULL;
639
640 plen = strlen(pi->name);
641 protected = 0;
642
643 /* check whether at least one realm covers the requested url */
644 for( i = 0; i < uh_realm_count; i++ )
645 {
646 realm = (struct auth_realm *)
647 &uh_realms[i * sizeof(struct auth_realm)];
648
649 rlen = strlen(realm->path);
650
651 if( (plen >= rlen) && !strncasecmp(pi->name, realm->path, rlen) )
652 {
653 req->realm = realm;
654 protected = 1;
655 break;
656 }
657 }
658
659 /* requested resource is covered by a realm */
660 if( protected )
661 {
662 /* try to get client auth info */
663 foreach_header(i, req->headers)
664 {
665 if( !strcasecmp(req->headers[i], "Authorization") &&
666 (strlen(req->headers[i+1]) > 6) &&
667 !strncasecmp(req->headers[i+1], "Basic ", 6)
668 ) {
669 memset(buffer, 0, sizeof(buffer));
670 uh_b64decode(buffer, sizeof(buffer) - 1,
671 (unsigned char *) &req->headers[i+1][6],
672 strlen(req->headers[i+1]) - 6);
673
674 if( (pass = strchr(buffer, ':')) != NULL )
675 {
676 user = buffer;
677 *pass++ = 0;
678 }
679
680 break;
681 }
682 }
683
684 /* have client auth */
685 if( user && pass )
686 {
687 /* find matching realm */
688 for( i = 0, realm = NULL; i < uh_realm_count; i++ )
689 {
690 realm = (struct auth_realm *)
691 &uh_realms[i * sizeof(struct auth_realm)];
692
693 rlen = strlen(realm->path);
694
695 if( (plen >= rlen) &&
696 !strncasecmp(pi->name, realm->path, rlen) &&
697 !strcmp(user, realm->user)
698 ) {
699 req->realm = realm;
700 break;
701 }
702
703 realm = NULL;
704 }
705
706 /* found a realm matching the username */
707 if( realm )
708 {
709 /* is a crypt passwd */
710 if( realm->pass[0] == '$' )
711 pass = crypt(pass, realm->pass);
712
713 /* check user pass */
714 if( !strcmp(pass, realm->pass) )
715 return 1;
716 }
717 }
718
719 /* 401 */
720 uh_http_sendf(cl, NULL,
721 "HTTP/%.1f 401 Authorization Required\r\n"
722 "WWW-Authenticate: Basic realm=\"%s\"\r\n"
723 "Content-Type: text/plain\r\n"
724 "Content-Length: 23\r\n\r\n"
725 "Authorization Required\n",
726 req->version, cl->server->conf->realm
727 );
728
729 return 0;
730 }
731
732 return 1;
733 }
734
735
736 static char uh_listeners[UH_LIMIT_LISTENERS * sizeof(struct listener)] = { 0 };
737 static char uh_clients[UH_LIMIT_CLIENTS * sizeof(struct client)] = { 0 };
738
739 static int uh_listener_count = 0;
740 static int uh_client_count = 0;
741
742
743 struct listener * uh_listener_add(int sock, struct config *conf)
744 {
745 struct listener *new = NULL;
746 socklen_t sl;
747
748 if( uh_listener_count < UH_LIMIT_LISTENERS )
749 {
750 new = (struct listener *)
751 &uh_listeners[uh_listener_count * sizeof(struct listener)];
752
753 new->socket = sock;
754 new->conf = conf;
755
756 /* get local endpoint addr */
757 sl = sizeof(struct sockaddr_in6);
758 memset(&(new->addr), 0, sl);
759 getsockname(sock, (struct sockaddr *) &(new->addr), &sl);
760
761 uh_listener_count++;
762 }
763
764 return new;
765 }
766
767 struct listener * uh_listener_lookup(int sock)
768 {
769 struct listener *cur = NULL;
770 int i;
771
772 for( i = 0; i < uh_listener_count; i++ )
773 {
774 cur = (struct listener *) &uh_listeners[i * sizeof(struct listener)];
775
776 if( cur->socket == sock )
777 return cur;
778 }
779
780 return NULL;
781 }
782
783
784 struct client * uh_client_add(int sock, struct listener *serv)
785 {
786 struct client *new = NULL;
787 socklen_t sl;
788
789 if( uh_client_count < UH_LIMIT_CLIENTS )
790 {
791 new = (struct client *)
792 &uh_clients[uh_client_count * sizeof(struct client)];
793
794 new->socket = sock;
795 new->server = serv;
796
797 /* get remote endpoint addr */
798 sl = sizeof(struct sockaddr_in6);
799 memset(&(new->peeraddr), 0, sl);
800 getpeername(sock, (struct sockaddr *) &(new->peeraddr), &sl);
801
802 /* get local endpoint addr */
803 sl = sizeof(struct sockaddr_in6);
804 memset(&(new->servaddr), 0, sl);
805 getsockname(sock, (struct sockaddr *) &(new->servaddr), &sl);
806
807 uh_client_count++;
808 }
809
810 return new;
811 }
812
813 struct client * uh_client_lookup(int sock)
814 {
815 struct client *cur = NULL;
816 int i;
817
818 for( i = 0; i < uh_client_count; i++ )
819 {
820 cur = (struct client *) &uh_clients[i * sizeof(struct client)];
821
822 if( cur->socket == sock )
823 return cur;
824 }
825
826 return NULL;
827 }
828
829 void uh_client_remove(int sock)
830 {
831 struct client *del = uh_client_lookup(sock);
832
833 if( del )
834 {
835 memmove(del, del + 1,
836 sizeof(uh_clients) - (int)((char *)del - uh_clients) - sizeof(struct client));
837
838 uh_client_count--;
839 }
840 }
841
842