xref: /PHP-8.1/main/fopen_wrappers.c (revision df579ada)
1 /*
2    +----------------------------------------------------------------------+
3    | Copyright (c) The PHP Group                                          |
4    +----------------------------------------------------------------------+
5    | This source file is subject to version 3.01 of the PHP license,      |
6    | that is bundled with this package in the file LICENSE, and is        |
7    | available through the world-wide-web at the following url:           |
8    | https://www.php.net/license/3_01.txt                                 |
9    | If you did not receive a copy of the PHP license and are unable to   |
10    | obtain it through the world-wide-web, please send a note to          |
11    | license@php.net so we can mail you a copy immediately.               |
12    +----------------------------------------------------------------------+
13    | Authors: Rasmus Lerdorf <rasmus@lerdorf.on.ca>                       |
14    |          Jim Winstead <jimw@php.net>                                 |
15    +----------------------------------------------------------------------+
16  */
17 
18 /* {{{ includes */
19 #include "php.h"
20 #include "php_globals.h"
21 #include "SAPI.h"
22 
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <errno.h>
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <fcntl.h>
29 
30 #ifdef PHP_WIN32
31 #define O_RDONLY _O_RDONLY
32 #include "win32/param.h"
33 #else
34 #include <sys/param.h>
35 #endif
36 
37 #include "ext/standard/head.h"
38 #include "ext/standard/php_standard.h"
39 #include "zend_compile.h"
40 #include "php_network.h"
41 
42 #if HAVE_PWD_H
43 #include <pwd.h>
44 #endif
45 
46 #include <sys/types.h>
47 #if HAVE_SYS_SOCKET_H
48 #include <sys/socket.h>
49 #endif
50 
51 #ifdef PHP_WIN32
52 #include <winsock2.h>
53 #else
54 #include <netinet/in.h>
55 #include <netdb.h>
56 #if HAVE_ARPA_INET_H
57 #include <arpa/inet.h>
58 #endif
59 #endif
60 
61 #if defined(PHP_WIN32) || defined(__riscos__)
62 #undef AF_UNIX
63 #endif
64 
65 #if defined(AF_UNIX)
66 #include <sys/un.h>
67 #endif
68 /* }}} */
69 
70 /* {{{ OnUpdateBaseDir
71 Allows any change to open_basedir setting in during Startup and Shutdown events,
72 or a tightening during activation/runtime/deactivation */
ZEND_INI_MH(OnUpdateBaseDir)73 PHPAPI ZEND_INI_MH(OnUpdateBaseDir)
74 {
75 	char **p = (char **) ZEND_INI_GET_ADDR();
76 	char *pathbuf, *ptr, *end;
77 
78 	if (stage == PHP_INI_STAGE_STARTUP || stage == PHP_INI_STAGE_SHUTDOWN || stage == PHP_INI_STAGE_ACTIVATE || stage == PHP_INI_STAGE_DEACTIVATE) {
79 		/* We're in a PHP_INI_SYSTEM context, no restrictions */
80 		*p = new_value ? ZSTR_VAL(new_value) : NULL;
81 		return SUCCESS;
82 	}
83 
84 	/* Otherwise we're in runtime */
85 	if (!*p || !**p) {
86 		/* open_basedir not set yet, go ahead and give it a value */
87 		*p = ZSTR_VAL(new_value);
88 		return SUCCESS;
89 	}
90 
91 	/* Shortcut: When we have a open_basedir and someone tries to unset, we know it'll fail */
92 	if (!new_value || !*ZSTR_VAL(new_value)) {
93 		return FAILURE;
94 	}
95 
96 	/* Is the proposed open_basedir at least as restrictive as the current setting? */
97 	ptr = pathbuf = estrdup(ZSTR_VAL(new_value));
98 	while (ptr && *ptr) {
99 		end = strchr(ptr, DEFAULT_DIR_SEPARATOR);
100 		if (end != NULL) {
101 			*end = '\0';
102 			end++;
103 		}
104 		if (ptr[0] == '.' && ptr[1] == '.' && (ptr[2] == '\0' || IS_SLASH(ptr[2]))) {
105 			/* Don't allow paths with a leading .. path component to be set at runtime */
106 			efree(pathbuf);
107 			return FAILURE;
108 		}
109 		if (php_check_open_basedir_ex(ptr, 0) != 0) {
110 			/* At least one portion of this open_basedir is less restrictive than the prior one, FAIL */
111 			efree(pathbuf);
112 			return FAILURE;
113 		}
114 		ptr = end;
115 	}
116 	efree(pathbuf);
117 
118 	/* Everything checks out, set it */
119 	*p = ZSTR_VAL(new_value);
120 
121 	return SUCCESS;
122 }
123 /* }}} */
124 
125 /* {{{ php_check_specific_open_basedir
126 	When open_basedir is not NULL, check if the given filename is located in
127 	open_basedir. Returns -1 if error or not in the open_basedir, else 0.
128 	When open_basedir is NULL, always return 0.
129 */
php_check_specific_open_basedir(const char * basedir,const char * path)130 PHPAPI int php_check_specific_open_basedir(const char *basedir, const char *path)
131 {
132 	char resolved_name[MAXPATHLEN + 1];
133 	char resolved_basedir[MAXPATHLEN + 1];
134 	char local_open_basedir[MAXPATHLEN];
135 	char path_tmp[MAXPATHLEN + 1];
136 	char *path_file;
137 	size_t resolved_basedir_len;
138 	size_t resolved_name_len;
139 	size_t path_len;
140 	int nesting_level = 0;
141 
142 	/* Special case basedir==".": Use script-directory */
143 	if (strcmp(basedir, ".") || !VCWD_GETCWD(local_open_basedir, MAXPATHLEN)) {
144 		/* Else use the unmodified path */
145 		strlcpy(local_open_basedir, basedir, sizeof(local_open_basedir));
146 	}
147 
148 	path_len = strlen(path);
149 	if (path_len > (MAXPATHLEN - 1)) {
150 		/* empty and too long paths are invalid */
151 		return -1;
152 	}
153 
154 	/* normalize and expand path */
155 	if (expand_filepath(path, resolved_name) == NULL) {
156 		return -1;
157 	}
158 
159 	path_len = strlen(resolved_name);
160 	memcpy(path_tmp, resolved_name, path_len + 1); /* safe */
161 
162 	while (VCWD_REALPATH(path_tmp, resolved_name) == NULL) {
163 #if defined(PHP_WIN32) || defined(HAVE_SYMLINK)
164 		if (nesting_level == 0) {
165 			ssize_t ret;
166 			char buf[MAXPATHLEN];
167 
168 			ret = php_sys_readlink(path_tmp, buf, MAXPATHLEN - 1);
169 			if (ret == -1) {
170 				/* not a broken symlink, move along.. */
171 			} else {
172 				/* put the real path into the path buffer */
173 				memcpy(path_tmp, buf, ret);
174 				path_tmp[ret] = '\0';
175 			}
176 		}
177 #endif
178 
179 #ifdef PHP_WIN32
180 		path_file = strrchr(path_tmp, DEFAULT_SLASH);
181 		if (!path_file) {
182 			path_file = strrchr(path_tmp, '/');
183 		}
184 #else
185 		path_file = strrchr(path_tmp, DEFAULT_SLASH);
186 #endif
187 		if (!path_file) {
188 			/* none of the path components exist. definitely not in open_basedir.. */
189 			return -1;
190 		} else {
191 			path_len = path_file - path_tmp + 1;
192 #ifdef PHP_WIN32
193 			if (path_len > 1 && path_tmp[path_len - 2] == ':') {
194 				if (path_len != 3) {
195 					return -1;
196 				}
197 				/* this is c:\ */
198 				path_tmp[path_len] = '\0';
199 			} else {
200 				path_tmp[path_len - 1] = '\0';
201 			}
202 #else
203 			path_tmp[path_len - 1] = '\0';
204 #endif
205 		}
206 		if (*path_tmp == '\0') {
207 			/* Do not pass an empty string to realpath(), as this will resolve to CWD. */
208 			break;
209 		}
210 		nesting_level++;
211 	}
212 
213 	/* Resolve open_basedir to resolved_basedir */
214 	if (expand_filepath(local_open_basedir, resolved_basedir) != NULL) {
215 		size_t basedir_len = strlen(basedir);
216 		/* Handler for basedirs that end with a / */
217 		resolved_basedir_len = strlen(resolved_basedir);
218 #ifdef PHP_WIN32
219 		if (basedir[basedir_len - 1] == PHP_DIR_SEPARATOR || basedir[basedir_len - 1] == '/') {
220 #else
221 		if (basedir[basedir_len - 1] == PHP_DIR_SEPARATOR) {
222 #endif
223 			if (resolved_basedir[resolved_basedir_len - 1] != PHP_DIR_SEPARATOR) {
224 				resolved_basedir[resolved_basedir_len] = PHP_DIR_SEPARATOR;
225 				resolved_basedir[++resolved_basedir_len] = '\0';
226 			}
227 		} else {
228 				resolved_basedir[resolved_basedir_len++] = PHP_DIR_SEPARATOR;
229 				resolved_basedir[resolved_basedir_len] = '\0';
230 		}
231 
232 		resolved_name_len = strlen(resolved_name);
233 		if (path_tmp[path_len - 1] == PHP_DIR_SEPARATOR) {
234 			if (resolved_name[resolved_name_len - 1] != PHP_DIR_SEPARATOR) {
235 				resolved_name[resolved_name_len] = PHP_DIR_SEPARATOR;
236 				resolved_name[++resolved_name_len] = '\0';
237 			}
238 		}
239 
240 		/* Check the path */
241 #ifdef PHP_WIN32
242 		if (strncasecmp(resolved_basedir, resolved_name, resolved_basedir_len) == 0) {
243 #else
244 		if (strncmp(resolved_basedir, resolved_name, resolved_basedir_len) == 0) {
245 #endif
246 			if (resolved_name_len > resolved_basedir_len &&
247 				resolved_name[resolved_basedir_len - 1] != PHP_DIR_SEPARATOR) {
248 				return -1;
249 			} else {
250 				/* File is in the right directory */
251 				return 0;
252 			}
253 		} else {
254 			/* /openbasedir/ and /openbasedir are the same directory */
255 			if (resolved_basedir_len == (resolved_name_len + 1) && resolved_basedir[resolved_basedir_len - 1] == PHP_DIR_SEPARATOR) {
256 #ifdef PHP_WIN32
257 				if (strncasecmp(resolved_basedir, resolved_name, resolved_name_len) == 0) {
258 #else
259 				if (strncmp(resolved_basedir, resolved_name, resolved_name_len) == 0) {
260 #endif
261 					return 0;
262 				}
263 			}
264 			return -1;
265 		}
266 	} else {
267 		/* Unable to resolve the real path, return -1 */
268 		return -1;
269 	}
270 }
271 /* }}} */
272 
273 PHPAPI int php_check_open_basedir(const char *path)
274 {
275 	return php_check_open_basedir_ex(path, 1);
276 }
277 
278 /* {{{ php_check_open_basedir */
279 PHPAPI int php_check_open_basedir_ex(const char *path, int warn)
280 {
281 	/* Only check when open_basedir is available */
282 	if (PG(open_basedir) && *PG(open_basedir)) {
283 		char *pathbuf;
284 		char *ptr;
285 		char *end;
286 
287 		/* Check if the path is too long so we can give a more useful error
288 		* message. */
289 		if (strlen(path) > (MAXPATHLEN - 1)) {
290 			php_error_docref(NULL, E_WARNING, "File name is longer than the maximum allowed path length on this platform (%d): %s", MAXPATHLEN, path);
291 			errno = EINVAL;
292 			return -1;
293 		}
294 
295 		pathbuf = estrdup(PG(open_basedir));
296 
297 		ptr = pathbuf;
298 
299 		while (ptr && *ptr) {
300 			end = strchr(ptr, DEFAULT_DIR_SEPARATOR);
301 			if (end != NULL) {
302 				*end = '\0';
303 				end++;
304 			}
305 
306 			if (php_check_specific_open_basedir(ptr, path) == 0) {
307 				efree(pathbuf);
308 				return 0;
309 			}
310 
311 			ptr = end;
312 		}
313 		if (warn) {
314 			php_error_docref(NULL, E_WARNING, "open_basedir restriction in effect. File(%s) is not within the allowed path(s): (%s)", path, PG(open_basedir));
315 		}
316 		efree(pathbuf);
317 		errno = EPERM; /* we deny permission to open it */
318 		return -1;
319 	}
320 
321 	/* Nothing to check... */
322 	return 0;
323 }
324 /* }}} */
325 
326 /* {{{ php_fopen_and_set_opened_path */
327 static FILE *php_fopen_and_set_opened_path(const char *path, const char *mode, zend_string **opened_path)
328 {
329 	FILE *fp;
330 
331 	if (php_check_open_basedir((char *)path)) {
332 		return NULL;
333 	}
334 	fp = VCWD_FOPEN(path, mode);
335 	if (fp && opened_path) {
336 		//TODO :avoid reallocation
337 		char *tmp = expand_filepath_with_mode(path, NULL, NULL, 0, CWD_EXPAND);
338 		if (tmp) {
339 			*opened_path = zend_string_init(tmp, strlen(tmp), 0);
340 			efree(tmp);
341 		}
342 	}
343 	return fp;
344 }
345 /* }}} */
346 
347 /* {{{ php_fopen_primary_script */
348 PHPAPI int php_fopen_primary_script(zend_file_handle *file_handle)
349 {
350 	char *path_info;
351 	zend_string *filename = NULL;
352 	zend_string *resolved_path = NULL;
353 	size_t length;
354 	bool orig_display_errors;
355 
356 	memset(file_handle, 0, sizeof(zend_file_handle));
357 
358 	path_info = SG(request_info).request_uri;
359 #if HAVE_PWD_H
360 	if (PG(user_dir) && *PG(user_dir) && path_info && '/' == path_info[0] && '~' == path_info[1]) {
361 		char *s = strchr(path_info + 2, '/');
362 
363 		if (s) {			/* if there is no path name after the file, do not bother */
364 			char user[32];			/* to try open the directory */
365 			struct passwd *pw;
366 #if defined(ZTS) && defined(HAVE_GETPWNAM_R) && defined(_SC_GETPW_R_SIZE_MAX)
367 			struct passwd pwstruc;
368 			long pwbuflen = sysconf(_SC_GETPW_R_SIZE_MAX);
369 			char *pwbuf;
370 
371 			if (pwbuflen < 1) {
372 				return FAILURE;
373 			}
374 
375 			pwbuf = emalloc(pwbuflen);
376 #endif
377 			length = s - (path_info + 2);
378 			if (length > sizeof(user) - 1) {
379 				length = sizeof(user) - 1;
380 			}
381 			memcpy(user, path_info + 2, length);
382 			user[length] = '\0';
383 #if defined(ZTS) && defined(HAVE_GETPWNAM_R) && defined(_SC_GETPW_R_SIZE_MAX)
384 			if (getpwnam_r(user, &pwstruc, pwbuf, pwbuflen, &pw)) {
385 				efree(pwbuf);
386 				return FAILURE;
387 			}
388 #else
389 			pw = getpwnam(user);
390 #endif
391 			if (pw && pw->pw_dir) {
392 				filename = zend_strpprintf(0, "%s%c%s%c%s", pw->pw_dir, PHP_DIR_SEPARATOR, PG(user_dir), PHP_DIR_SEPARATOR, s + 1); /* Safe */
393 			} else if (SG(request_info).path_translated) {
394 				filename = zend_string_init(SG(request_info).path_translated,
395 					strlen(SG(request_info).path_translated), 0);
396 			}
397 #if defined(ZTS) && defined(HAVE_GETPWNAM_R) && defined(_SC_GETPW_R_SIZE_MAX)
398 			efree(pwbuf);
399 #endif
400 		}
401 	} else
402 #endif
403 	if (PG(doc_root) && path_info && (length = strlen(PG(doc_root))) &&
404 		IS_ABSOLUTE_PATH(PG(doc_root), length)) {
405 		size_t path_len = strlen(path_info);
406 		filename = zend_string_alloc(length + path_len + 2, 0);
407 		memcpy(ZSTR_VAL(filename), PG(doc_root), length);
408 		if (!IS_SLASH(ZSTR_VAL(filename)[length - 1])) {	/* length is never 0 */
409 			ZSTR_VAL(filename)[length++] = PHP_DIR_SEPARATOR;
410 		}
411 		if (IS_SLASH(path_info[0])) {
412 			length--;
413 		}
414 		strncpy(ZSTR_VAL(filename) + length, path_info, path_len + 1);
415 		ZSTR_LEN(filename) = length + path_len;
416 	} else if (SG(request_info).path_translated) {
417 		filename = zend_string_init(SG(request_info).path_translated,
418 			strlen(SG(request_info).path_translated), 0);
419 	}
420 
421 
422 	if (filename) {
423 		resolved_path = zend_resolve_path(filename);
424 	}
425 
426 	if (!resolved_path) {
427 		if (filename) {
428 			zend_string_release(filename);
429 		}
430 		/* we have to free SG(request_info).path_translated here because
431 		 * php_destroy_request_info assumes that it will get
432 		 * freed when the include_names hash is emptied, but
433 		 * we're not adding it in this case */
434 		if (SG(request_info).path_translated) {
435 			efree(SG(request_info).path_translated);
436 			SG(request_info).path_translated = NULL;
437 		}
438 		return FAILURE;
439 	}
440 	zend_string_release_ex(resolved_path, 0);
441 
442 	orig_display_errors = PG(display_errors);
443 	PG(display_errors) = 0;
444 	zend_stream_init_filename_ex(file_handle, filename);
445 	file_handle->primary_script = 1;
446 	if (filename) {
447 		zend_string_delref(filename);
448 	}
449 	if (zend_stream_open(file_handle) == FAILURE) {
450 		PG(display_errors) = orig_display_errors;
451 		if (SG(request_info).path_translated) {
452 			efree(SG(request_info).path_translated);
453 			SG(request_info).path_translated = NULL;
454 		}
455 		return FAILURE;
456 	}
457 	PG(display_errors) = orig_display_errors;
458 
459 	return SUCCESS;
460 }
461 /* }}} */
462 
463 static zend_string *tsrm_realpath_str(const char *path) {
464 	char *realpath = tsrm_realpath(path, NULL);
465 	if (!realpath) {
466 		return NULL;
467 	}
468 	zend_string *realpath_str = zend_string_init(realpath, strlen(realpath), 0);
469 	efree(realpath);
470 	return realpath_str;
471 }
472 
473 /* {{{ php_resolve_path
474  * Returns the realpath for given filename according to include path
475  */
476 PHPAPI zend_string *php_resolve_path(const char *filename, size_t filename_length, const char *path)
477 {
478 	zend_string *resolved_path;
479 	char trypath[MAXPATHLEN];
480 	const char *ptr, *end, *p;
481 	const char *actual_path;
482 	php_stream_wrapper *wrapper;
483 	zend_string *exec_filename;
484 
485 	if (!filename || CHECK_NULL_PATH(filename, filename_length)) {
486 		return NULL;
487 	}
488 
489 	/* Don't resolve paths which contain protocol (except of file://) */
490 	for (p = filename; isalnum((int)*p) || *p == '+' || *p == '-' || *p == '.'; p++);
491 	if ((*p == ':') && (p - filename > 1) && (p[1] == '/') && (p[2] == '/')) {
492 		wrapper = php_stream_locate_url_wrapper(filename, &actual_path, STREAM_OPEN_FOR_INCLUDE);
493 		if (wrapper == &php_plain_files_wrapper) {
494 			if ((resolved_path = tsrm_realpath_str(actual_path))) {
495 				return resolved_path;
496 			}
497 		}
498 		return NULL;
499 	}
500 
501 	if ((*filename == '.' &&
502 	     (IS_SLASH(filename[1]) ||
503 	      ((filename[1] == '.') && IS_SLASH(filename[2])))) ||
504 	    IS_ABSOLUTE_PATH(filename, filename_length) ||
505 #ifdef PHP_WIN32
506 		/* This should count as an absolute local path as well, however
507 		   IS_ABSOLUTE_PATH doesn't care about this path form till now. It
508 		   might be a big thing to extend, thus just a local handling for
509 		   now. */
510 		filename_length >=2 && IS_SLASH(filename[0]) && !IS_SLASH(filename[1]) ||
511 #endif
512 	    !path ||
513 	    !*path) {
514 		return tsrm_realpath_str(filename);
515 	}
516 
517 	ptr = path;
518 	while (ptr && *ptr) {
519 		/* Check for stream wrapper */
520 		int is_stream_wrapper = 0;
521 
522 		for (p = ptr; isalnum((int)*p) || *p == '+' || *p == '-' || *p == '.'; p++);
523 		if ((*p == ':') && (p - ptr > 1) && (p[1] == '/') && (p[2] == '/')) {
524 			/* .:// or ..:// is not a stream wrapper */
525 			if (p[-1] != '.' || p[-2] != '.' || p - 2 != ptr) {
526 				p += 3;
527 				is_stream_wrapper = 1;
528 			}
529 		}
530 		end = strchr(p, DEFAULT_DIR_SEPARATOR);
531 		if (end) {
532 			if (filename_length > (MAXPATHLEN - 2) || (end-ptr) > MAXPATHLEN || (end-ptr) + 1 + filename_length + 1 >= MAXPATHLEN) {
533 				ptr = end + 1;
534 				continue;
535 			}
536 			memcpy(trypath, ptr, end-ptr);
537 			trypath[end-ptr] = '/';
538 			memcpy(trypath+(end-ptr)+1, filename, filename_length+1);
539 			ptr = end+1;
540 		} else {
541 			size_t len = strlen(ptr);
542 
543 			if (filename_length > (MAXPATHLEN - 2) || len > MAXPATHLEN || len + 1 + filename_length + 1 >= MAXPATHLEN) {
544 				break;
545 			}
546 			memcpy(trypath, ptr, len);
547 			trypath[len] = '/';
548 			memcpy(trypath+len+1, filename, filename_length+1);
549 			ptr = NULL;
550 		}
551 		actual_path = trypath;
552 		if (is_stream_wrapper) {
553 			wrapper = php_stream_locate_url_wrapper(trypath, &actual_path, STREAM_OPEN_FOR_INCLUDE);
554 			if (!wrapper) {
555 				continue;
556 			} else if (wrapper != &php_plain_files_wrapper) {
557 				if (wrapper->wops->url_stat) {
558 					php_stream_statbuf ssb;
559 
560 					if (SUCCESS == wrapper->wops->url_stat(wrapper, trypath, PHP_STREAM_URL_STAT_QUIET, &ssb, NULL)) {
561 						return zend_string_init(trypath, strlen(trypath), 0);
562 					}
563 					if (EG(exception)) {
564 						return NULL;
565 					}
566 				}
567 				continue;
568 			}
569 		}
570 		if ((resolved_path = tsrm_realpath_str(actual_path))) {
571 			return resolved_path;
572 		}
573 	} /* end provided path */
574 
575 	/* check in calling scripts' current working directory as a fall back case
576 	 */
577 	if (zend_is_executing() &&
578 	    (exec_filename = zend_get_executed_filename_ex()) != NULL) {
579 		const char *exec_fname = ZSTR_VAL(exec_filename);
580 		size_t exec_fname_length = ZSTR_LEN(exec_filename);
581 
582 		while ((--exec_fname_length < SIZE_MAX) && !IS_SLASH(exec_fname[exec_fname_length]));
583 		if (exec_fname_length > 0 &&
584 			filename_length < (MAXPATHLEN - 2) &&
585 		    exec_fname_length + 1 + filename_length + 1 < MAXPATHLEN) {
586 			memcpy(trypath, exec_fname, exec_fname_length + 1);
587 			memcpy(trypath+exec_fname_length + 1, filename, filename_length+1);
588 			actual_path = trypath;
589 
590 			/* Check for stream wrapper */
591 			for (p = trypath; isalnum((int)*p) || *p == '+' || *p == '-' || *p == '.'; p++);
592 			if ((*p == ':') && (p - trypath > 1) && (p[1] == '/') && (p[2] == '/')) {
593 				wrapper = php_stream_locate_url_wrapper(trypath, &actual_path, STREAM_OPEN_FOR_INCLUDE);
594 				if (!wrapper) {
595 					return NULL;
596 				} else if (wrapper != &php_plain_files_wrapper) {
597 					if (wrapper->wops->url_stat) {
598 						php_stream_statbuf ssb;
599 
600 						if (SUCCESS == wrapper->wops->url_stat(wrapper, trypath, PHP_STREAM_URL_STAT_QUIET, &ssb, NULL)) {
601 							return zend_string_init(trypath, strlen(trypath), 0);
602 						}
603 						if (EG(exception)) {
604 							return NULL;
605 						}
606 					}
607 					return NULL;
608 				}
609 			}
610 
611 			return tsrm_realpath_str(actual_path);
612 		}
613 	}
614 
615 	return NULL;
616 }
617 /* }}} */
618 
619 /* {{{ php_fopen_with_path
620  * Tries to open a file with a PATH-style list of directories.
621  * If the filename starts with "." or "/", the path is ignored.
622  */
623 PHPAPI FILE *php_fopen_with_path(const char *filename, const char *mode, const char *path, zend_string **opened_path)
624 {
625 	char *pathbuf, *ptr, *end;
626 	char trypath[MAXPATHLEN];
627 	FILE *fp;
628 	size_t filename_length;
629 	zend_string *exec_filename;
630 
631 	if (opened_path) {
632 		*opened_path = NULL;
633 	}
634 
635 	if (!filename) {
636 		return NULL;
637 	}
638 
639 	filename_length = strlen(filename);
640 #ifndef PHP_WIN32
641 	(void) filename_length;
642 #endif
643 
644 	/* Relative path open */
645 	if ((*filename == '.')
646 	/* Absolute path open */
647 	 || IS_ABSOLUTE_PATH(filename, filename_length)
648 	 || (!path || !*path)
649 	) {
650 		return php_fopen_and_set_opened_path(filename, mode, opened_path);
651 	}
652 
653 	/* check in provided path */
654 	/* append the calling scripts' current working directory
655 	 * as a fall back case
656 	 */
657 	if (zend_is_executing() &&
658 	    (exec_filename = zend_get_executed_filename_ex()) != NULL) {
659 		const char *exec_fname = ZSTR_VAL(exec_filename);
660 		size_t exec_fname_length = ZSTR_LEN(exec_filename);
661 
662 		while ((--exec_fname_length < SIZE_MAX) && !IS_SLASH(exec_fname[exec_fname_length]));
663 		if ((exec_fname && exec_fname[0] == '[') || exec_fname_length <= 0) {
664 			/* [no active file] or no path */
665 			pathbuf = estrdup(path);
666 		} else {
667 			size_t path_length = strlen(path);
668 
669 			pathbuf = (char *) emalloc(exec_fname_length + path_length + 1 + 1);
670 			memcpy(pathbuf, path, path_length);
671 			pathbuf[path_length] = DEFAULT_DIR_SEPARATOR;
672 			memcpy(pathbuf + path_length + 1, exec_fname, exec_fname_length);
673 			pathbuf[path_length + exec_fname_length + 1] = '\0';
674 		}
675 	} else {
676 		pathbuf = estrdup(path);
677 	}
678 
679 	ptr = pathbuf;
680 
681 	while (ptr && *ptr) {
682 		end = strchr(ptr, DEFAULT_DIR_SEPARATOR);
683 		if (end != NULL) {
684 			*end = '\0';
685 			end++;
686 		}
687 		if (snprintf(trypath, MAXPATHLEN, "%s/%s", ptr, filename) >= MAXPATHLEN) {
688 			php_error_docref(NULL, E_NOTICE, "%s/%s path was truncated to %d", ptr, filename, MAXPATHLEN);
689 		}
690 		fp = php_fopen_and_set_opened_path(trypath, mode, opened_path);
691 		if (fp) {
692 			efree(pathbuf);
693 			return fp;
694 		}
695 		ptr = end;
696 	} /* end provided path */
697 
698 	efree(pathbuf);
699 	return NULL;
700 }
701 /* }}} */
702 
703 /* {{{ php_strip_url_passwd */
704 PHPAPI char *php_strip_url_passwd(char *url)
705 {
706 	char *p, *url_start;
707 
708 	if (url == NULL) {
709 		return "";
710 	}
711 
712 	p = url;
713 
714 	while (*p) {
715 		if (*p == ':' && *(p + 1) == '/' && *(p + 2) == '/') {
716 			/* found protocol */
717 			url_start = p = p + 3;
718 
719 			while (*p) {
720 				if (*p == '@') {
721 					int i;
722 
723 					for (i = 0; i < 3 && url_start < p; i++, url_start++) {
724 						*url_start = '.';
725 					}
726 					for (; *p; p++) {
727 						*url_start++ = *p;
728 					}
729 					*url_start=0;
730 					break;
731 				}
732 				p++;
733 			}
734 			return url;
735 		}
736 		p++;
737 	}
738 	return url;
739 }
740 /* }}} */
741 
742 /* {{{ expand_filepath */
743 PHPAPI char *expand_filepath(const char *filepath, char *real_path)
744 {
745 	return expand_filepath_ex(filepath, real_path, NULL, 0);
746 }
747 /* }}} */
748 
749 /* {{{ expand_filepath_ex */
750 PHPAPI char *expand_filepath_ex(const char *filepath, char *real_path, const char *relative_to, size_t relative_to_len)
751 {
752 	return expand_filepath_with_mode(filepath, real_path, relative_to, relative_to_len, CWD_FILEPATH);
753 }
754 /* }}} */
755 
756 /* {{{ expand_filepath_use_realpath */
757 PHPAPI char *expand_filepath_with_mode(const char *filepath, char *real_path, const char *relative_to, size_t relative_to_len, int realpath_mode)
758 {
759 	cwd_state new_state;
760 	char cwd[MAXPATHLEN];
761 	size_t copy_len;
762 	size_t path_len;
763 
764 	if (!filepath[0]) {
765 		return NULL;
766 	}
767 
768 	path_len = strlen(filepath);
769 
770 	if (IS_ABSOLUTE_PATH(filepath, path_len)) {
771 		cwd[0] = '\0';
772 	} else {
773 		const char *iam = SG(request_info).path_translated;
774 		const char *result;
775 		if (relative_to) {
776 			if (relative_to_len > MAXPATHLEN-1U) {
777 				return NULL;
778 			}
779 			result = relative_to;
780 			memcpy(cwd, relative_to, relative_to_len+1U);
781 		} else {
782 			result = VCWD_GETCWD(cwd, MAXPATHLEN);
783 		}
784 
785 		if (!result && (iam != filepath)) {
786 			int fdtest = -1;
787 
788 			fdtest = VCWD_OPEN(filepath, O_RDONLY);
789 			if (fdtest != -1) {
790 				/* return a relative file path if for any reason
791 				 * we cannot cannot getcwd() and the requested,
792 				 * relatively referenced file is accessible */
793 				copy_len = path_len > MAXPATHLEN - 1 ? MAXPATHLEN - 1 : path_len;
794 				if (real_path) {
795 					memcpy(real_path, filepath, copy_len);
796 					real_path[copy_len] = '\0';
797 				} else {
798 					real_path = estrndup(filepath, copy_len);
799 				}
800 				close(fdtest);
801 				return real_path;
802 			} else {
803 				cwd[0] = '\0';
804 			}
805 		} else if (!result) {
806 			cwd[0] = '\0';
807 		}
808 	}
809 
810 	new_state.cwd = estrdup(cwd);
811 	new_state.cwd_length = strlen(cwd);
812 
813 	if (virtual_file_ex(&new_state, filepath, NULL, realpath_mode)) {
814 		efree(new_state.cwd);
815 		return NULL;
816 	}
817 
818 	if (real_path) {
819 		copy_len = new_state.cwd_length > MAXPATHLEN - 1 ? MAXPATHLEN - 1 : new_state.cwd_length;
820 		memcpy(real_path, new_state.cwd, copy_len);
821 		real_path[copy_len] = '\0';
822 	} else {
823 		real_path = estrndup(new_state.cwd, new_state.cwd_length);
824 	}
825 	efree(new_state.cwd);
826 
827 	return real_path;
828 }
829 /* }}} */
830