xref: /illumos-gate/usr/src/cmd/sgs/rtld/common/paths.c (revision 602ca9ea)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  *	Copyright (c) 1988 AT&T
24  *	  All Rights Reserved
25  *
26  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 /*
32  * PATH setup and search directory functions.
33  */
34 #include	"_synonyms.h"
35 
36 #include	<stdio.h>
37 #include	<limits.h>
38 #include	<fcntl.h>
39 #include	<string.h>
40 #include	<sys/systeminfo.h>
41 #include	<debug.h>
42 #include	<conv.h>
43 #include	"_rtld.h"
44 #include	"msg.h"
45 
46 /*
47  * Given a search rule type, return a list of directories to search according
48  * to the specified rule.
49  */
50 static Pnode *
51 get_dir_list(uchar_t rules, Rt_map *lmp, uint_t flags)
52 {
53 	Pnode *		dirlist = (Pnode *)0;
54 	Lm_list *	lml = LIST(lmp);
55 	int		search;
56 
57 	/*
58 	 * Determine whether ldd -s is in effect - ignore when we're searching
59 	 * for audit libraries as these will be added to their own link-map.
60 	 */
61 	if ((lml->lm_flags & LML_FLG_TRC_SEARCH) &&
62 	    ((FLAGS1(lmp) & FL1_RT_LDDSTUB) == 0) &&
63 	    ((flags & FLG_RT_AUDIT) == 0))
64 		search = 1;
65 	else
66 		search = 0;
67 
68 	switch (rules) {
69 	case RPLENV:
70 		/*
71 		 * Initialize the replaceable environment variable
72 		 * (LD_LIBRARY_PATH) search path list.  Note, we always call
73 		 * Dbg_libs_path() so that every library lookup diagnostic can
74 		 * be preceded with the appropriate search path information.
75 		 */
76 		if (rpl_libpath) {
77 			uint_t	mode = (LA_SER_LIBPATH | PN_FLG_UNIQUE);
78 
79 			/*
80 			 * Note, this path may have originated from the users
81 			 * environment or from a configuration file.
82 			 */
83 			if (env_info & ENV_INF_PATHCFG)
84 				mode |= LA_SER_CONFIG;
85 
86 			DBG_CALL(Dbg_libs_path(lml, rpl_libpath, mode,
87 			    config->c_name));
88 
89 			/*
90 			 * For ldd(1) -s, indicate the search paths that'll
91 			 * be used.  If this is a secure program then some
92 			 * search paths may be ignored, therefore reset the
93 			 * rpl_libdirs pointer each time so that the
94 			 * diagnostics related to these unsecure directories
95 			 * will be output for each image loaded.
96 			 */
97 			if (search) {
98 				const char	*fmt;
99 
100 				if (env_info & ENV_INF_PATHCFG)
101 					fmt = MSG_INTL(MSG_LDD_PTH_LIBPATHC);
102 				else
103 					fmt = MSG_INTL(MSG_LDD_PTH_LIBPATH);
104 
105 				(void) printf(fmt, rpl_libpath, config->c_name);
106 			}
107 			if (rpl_libdirs && (rtld_flags & RT_FL_SECURE) &&
108 			    (search || DBG_ENABLED)) {
109 				free(rpl_libdirs);
110 				rpl_libdirs = 0;
111 			}
112 			if (!rpl_libdirs) {
113 				/*
114 				 * If this is a secure application we need to
115 				 * be selective over what directories we use.
116 				 */
117 				rpl_libdirs = expand_paths(lmp, rpl_libpath,
118 				    mode, PN_TKN_HWCAP);
119 			}
120 			dirlist = rpl_libdirs;
121 		}
122 		break;
123 	case PRMENV:
124 		/*
125 		 * Initialize the permanent (LD_LIBRARY_PATH) search path list.
126 		 * This can only originate from a configuration file.  To be
127 		 * consistent with the debugging display of DEFENV (above),
128 		 * always call Dbg_libs_path().
129 		 */
130 		if (prm_libpath) {
131 			uint_t	mode =
132 			    (LA_SER_LIBPATH | LA_SER_CONFIG | PN_FLG_UNIQUE);
133 
134 			DBG_CALL(Dbg_libs_path(lml, prm_libpath, mode,
135 			    config->c_name));
136 
137 			/*
138 			 * For ldd(1) -s, indicate the search paths that'll
139 			 * be used.  If this is a secure program then some
140 			 * search paths may be ignored, therefore reset the
141 			 * prm_libdirs pointer each time so that the
142 			 * diagnostics related to these unsecure directories
143 			 * will be output for each image loaded.
144 			 */
145 			if (search)
146 				(void) printf(MSG_INTL(MSG_LDD_PTH_LIBPATHC),
147 				    prm_libpath, config->c_name);
148 			if (prm_libdirs && (rtld_flags & RT_FL_SECURE) &&
149 			    (search || DBG_ENABLED)) {
150 				free(prm_libdirs);
151 				prm_libdirs = 0;
152 			}
153 			if (!prm_libdirs) {
154 				/*
155 				 * If this is a secure application we need to
156 				 * be selective over what directories we use.
157 				 */
158 				prm_libdirs = expand_paths(lmp, prm_libpath,
159 				    mode, PN_TKN_HWCAP);
160 			}
161 			dirlist = prm_libdirs;
162 		}
163 		break;
164 	case RUNPATH:
165 		/*
166 		 * Initialize the runpath search path list.  To be consistent
167 		 * with the debugging display of DEFENV (above), always call
168 		 * Dbg_libs_path().
169 		 */
170 		if (RPATH(lmp)) {
171 			DBG_CALL(Dbg_libs_path(lml, RPATH(lmp), LA_SER_RUNPATH,
172 			    NAME(lmp)));
173 
174 			/*
175 			 * For ldd(1) -s, indicate the search paths that'll
176 			 * be used.  If this is a secure program then some
177 			 * search paths may be ignored, therefore reset the
178 			 * runlist pointer each time so that the diagnostics
179 			 * related to these unsecure directories will be
180 			 * output for each image loaded.
181 			 */
182 			if (search)
183 				(void) printf(MSG_INTL(MSG_LDD_PTH_RUNPATH),
184 				    RPATH(lmp), NAME(lmp));
185 			if (RLIST(lmp) && (rtld_flags & RT_FL_SECURE) &&
186 			    (search || DBG_ENABLED)) {
187 				free(RLIST(lmp));
188 				RLIST(lmp) = 0;
189 			}
190 			if (!(RLIST(lmp)))
191 				/*
192 				 * If this is a secure application we need to
193 				 * be selective over what directories we use.
194 				 */
195 				RLIST(lmp) = expand_paths(lmp, RPATH(lmp),
196 				    LA_SER_RUNPATH, PN_TKN_HWCAP);
197 			dirlist = RLIST(lmp);
198 		}
199 		break;
200 	case DEFAULT:
201 		if ((FLAGS1(lmp) & FL1_RT_NODEFLIB) == 0) {
202 			if ((rtld_flags & RT_FL_SECURE) &&
203 			    (flags & (FLG_RT_PRELOAD | FLG_RT_AUDIT)))
204 				dirlist = LM_SECURE_DIRS(lmp);
205 			else
206 				dirlist = LM_DFLT_DIRS(lmp);
207 		}
208 
209 		/*
210 		 * For ldd(1) -s, indicate the default paths that'll be used.
211 		 */
212 		if (dirlist && (search || DBG_ENABLED)) {
213 			Pnode *	pnp = dirlist;
214 			int	num = 0;
215 
216 			if (search)
217 				(void) printf(MSG_INTL(MSG_LDD_PTH_BGNDFL));
218 			for (; pnp && pnp->p_name; pnp = pnp->p_next, num++) {
219 				if (search) {
220 					const char	*fmt;
221 
222 					if (num) {
223 						fmt =
224 						    MSG_ORIG(MSG_LDD_FMT_PATHN);
225 					} else {
226 						fmt =
227 						    MSG_ORIG(MSG_LDD_FMT_PATH1);
228 					}
229 					(void) printf(fmt, pnp->p_name);
230 				} else
231 					DBG_CALL(Dbg_libs_path(lml, pnp->p_name,
232 					    pnp->p_orig, config->c_name));
233 			}
234 			/* BEGIN CSTYLED */
235 			if (search) {
236 				if (dirlist->p_orig & LA_SER_CONFIG)
237 				    (void) printf(MSG_INTL(MSG_LDD_PTH_ENDDFLC),
238 					config->c_name);
239 				else
240 				    (void) printf(MSG_INTL(MSG_LDD_PTH_ENDDFL));
241 			}
242 			/* END CSTYLED */
243 		}
244 		break;
245 	default:
246 		break;
247 	}
248 	return (dirlist);
249 }
250 
251 /*
252  * Get the next dir in the search rules path.
253  */
254 Pnode *
255 get_next_dir(Pnode ** dirlist, Rt_map * lmp, uint_t flags)
256 {
257 	static unsigned char	*rules = NULL;
258 
259 	/*
260 	 * Search rules consist of one or more directories names. If this is a
261 	 * new search, then start at the beginning of the search rules.
262 	 * Otherwise traverse the list of directories that make up the rule.
263 	 */
264 	if (!*dirlist) {
265 		rules = search_rules;
266 	} else {
267 		if ((*dirlist = (*dirlist)->p_next) != 0)
268 			return (*dirlist);
269 		else
270 			rules++;
271 	}
272 
273 	while (*rules) {
274 		if ((*dirlist = get_dir_list(*rules, lmp, flags)) != 0)
275 			return (*dirlist);
276 		else
277 			rules++;
278 	}
279 
280 	/*
281 	 * If we got here, no more directories to search, return NULL.
282 	 */
283 	return (NULL);
284 }
285 
286 /*
287  * Process a directory (runpath) or filename (needed or filter) string looking
288  * for tokens to expand.  Allocate a new buffer for the string.
289  */
290 uint_t
291 expand(char **name, size_t *len, char **list, uint_t orig, uint_t omit,
292     Rt_map *lmp)
293 {
294 	char	_name[PATH_MAX];
295 	char	*token = 0, *oname, *optr, *_optr, *nptr, * _list;
296 	size_t	olen = 0, nlen = 0, _len;
297 	int	isaflag = 0;
298 	uint_t	flags = 0;
299 	Lm_list	*lml = LIST(lmp);
300 
301 	optr = _optr = oname = *name;
302 	nptr = _name;
303 
304 	while ((olen < *len) && (nlen < PATH_MAX)) {
305 		uint_t	_flags;
306 
307 		if ((*optr != '$') || ((olen - *len) == 1)) {
308 			/*
309 			 * When expanding paths while a configuration file
310 			 * exists that contains directory information, determine
311 			 * whether the path contains "./".  If so, we'll resolve
312 			 * the path later to remove these relative entries.
313 			 */
314 			if ((rtld_flags & RT_FL_DIRCFG) &&
315 			    (orig & LA_SER_MASK) && (*optr == '/') &&
316 			    (optr != oname) && (*(optr - 1) == '.'))
317 				flags |= TKN_DOTSLASH;
318 
319 			olen++, optr++;
320 			continue;
321 		}
322 
323 		/*
324 		 * Copy any string we've presently passed over to the new
325 		 * buffer.
326 		 */
327 		if ((_len = (optr - _optr)) != 0) {
328 			if ((nlen += _len) < PATH_MAX) {
329 				(void) strncpy(nptr, _optr, _len);
330 				nptr = nptr + _len;
331 			} else {
332 				eprintf(lml, ERR_FATAL,
333 				    MSG_INTL(MSG_ERR_EXPAND1), NAME(lmp),
334 				    oname);
335 				return (0);
336 			}
337 		}
338 
339 		/*
340 		 * Skip the token delimiter and determine if a reserved token
341 		 * match is found.
342 		 */
343 		olen++, optr++;
344 		_flags = 0;
345 		token = 0;
346 
347 		if (strncmp(optr, MSG_ORIG(MSG_TKN_ORIGIN),
348 		    MSG_TKN_ORIGIN_SIZE) == 0) {
349 			token = (char *)MSG_ORIG(MSG_TKN_ORIGIN);
350 
351 			/*
352 			 * $ORIGIN expansion is required.  Determine this
353 			 * objects basename.  Expansion of $ORIGIN is allowed
354 			 * for secure applications but must be checked by the
355 			 * caller to insure the expanded path matches a
356 			 * registered secure name.
357 			 */
358 			if (((omit & PN_TKN_ORIGIN) == 0) &&
359 			    (((_len = DIRSZ(lmp)) != 0) ||
360 			    ((_len = fullpath(lmp, 0)) != 0))) {
361 				if ((nlen += _len) < PATH_MAX) {
362 					(void) strncpy(nptr,
363 					    ORIGNAME(lmp), _len);
364 					nptr = nptr +_len;
365 					olen += MSG_TKN_ORIGIN_SIZE;
366 					optr += MSG_TKN_ORIGIN_SIZE;
367 					_flags |= PN_TKN_ORIGIN;
368 				} else {
369 					eprintf(lml, ERR_FATAL,
370 					    MSG_INTL(MSG_ERR_EXPAND1),
371 					    NAME(lmp), oname);
372 					return (0);
373 				}
374 			}
375 
376 		} else if (strncmp(optr, MSG_ORIG(MSG_TKN_PLATFORM),
377 		    MSG_TKN_PLATFORM_SIZE) == 0) {
378 			token = (char *)MSG_ORIG(MSG_TKN_PLATFORM);
379 
380 			/*
381 			 * $PLATFORM expansion required.  This would have been
382 			 * established from the AT_SUN_PLATFORM aux vector, but
383 			 * if not attempt to get it from sysconf().
384 			 */
385 			if (((omit & PN_TKN_PLATFORM) == 0) &&
386 			    ((platform == 0) && (platform_sz == 0))) {
387 				char	_info[SYS_NMLN];
388 				long	_size;
389 
390 				_size = sysinfo(SI_PLATFORM, _info, SYS_NMLN);
391 				if ((_size != -1) &&
392 				    ((platform = malloc((size_t)_size)) != 0)) {
393 					(void) strcpy(platform, _info);
394 					platform_sz = (size_t)_size - 1;
395 				}
396 			}
397 			if (((omit & PN_TKN_PLATFORM) == 0) &&
398 			    (platform != 0)) {
399 				if ((nlen += platform_sz) < PATH_MAX) {
400 					(void) strncpy(nptr, platform,
401 					    platform_sz);
402 					nptr = nptr + platform_sz;
403 					olen += MSG_TKN_PLATFORM_SIZE;
404 					optr += MSG_TKN_PLATFORM_SIZE;
405 					_flags |= PN_TKN_PLATFORM;
406 				} else {
407 					eprintf(lml, ERR_FATAL,
408 					    MSG_INTL(MSG_ERR_EXPAND1),
409 					    NAME(lmp), oname);
410 					return (0);
411 				}
412 			}
413 
414 		} else if (strncmp(optr, MSG_ORIG(MSG_TKN_OSNAME),
415 		    MSG_TKN_OSNAME_SIZE) == 0) {
416 			token = (char *)MSG_ORIG(MSG_TKN_OSNAME);
417 
418 			/*
419 			 * $OSNAME expansion required.  This is established
420 			 * from the sysname[] returned by uname(2).
421 			 */
422 			if (((omit & PN_TKN_OSNAME) == 0) && (uts == 0))
423 				uts = conv_uts();
424 
425 			if (((omit & PN_TKN_OSNAME) == 0) &&
426 			    (uts && uts->uts_osnamesz)) {
427 				if ((nlen += uts->uts_osnamesz) < PATH_MAX) {
428 					(void) strncpy(nptr, uts->uts_osname,
429 					    uts->uts_osnamesz);
430 					nptr = nptr + uts->uts_osnamesz;
431 					olen += MSG_TKN_OSNAME_SIZE;
432 					optr += MSG_TKN_OSNAME_SIZE;
433 					_flags |= PN_TKN_OSNAME;
434 				} else {
435 					eprintf(lml, ERR_FATAL,
436 					    MSG_INTL(MSG_ERR_EXPAND1),
437 					    NAME(lmp), oname);
438 					return (0);
439 				}
440 			}
441 
442 		} else if (strncmp(optr, MSG_ORIG(MSG_TKN_OSREL),
443 		    MSG_TKN_OSREL_SIZE) == 0) {
444 			token = (char *)MSG_ORIG(MSG_TKN_OSREL);
445 
446 			/*
447 			 * $OSREL expansion required.  This is established
448 			 * from the release[] returned by uname(2).
449 			 */
450 			if (((omit & PN_TKN_OSREL) == 0) && (uts == 0))
451 				uts = conv_uts();
452 
453 			if (((omit & PN_TKN_OSREL) == 0) &&
454 			    (uts && uts->uts_osrelsz)) {
455 				if ((nlen += uts->uts_osrelsz) < PATH_MAX) {
456 					(void) strncpy(nptr, uts->uts_osrel,
457 					    uts->uts_osrelsz);
458 					nptr = nptr + uts->uts_osrelsz;
459 					olen += MSG_TKN_OSREL_SIZE;
460 					optr += MSG_TKN_OSREL_SIZE;
461 					_flags |= PN_TKN_OSREL;
462 				} else {
463 					eprintf(lml, ERR_FATAL,
464 					    MSG_INTL(MSG_ERR_EXPAND1),
465 					    NAME(lmp), oname);
466 					return (0);
467 				}
468 			}
469 
470 		} else if ((strncmp(optr, MSG_ORIG(MSG_TKN_ISALIST),
471 		    MSG_TKN_ISALIST_SIZE) == 0)) {
472 			int	ok;
473 			token = (char *)MSG_ORIG(MSG_TKN_ISALIST);
474 
475 			/*
476 			 * $ISALIST expansion required.  When accompanied with
477 			 * a list pointer, this routine updates that pointer
478 			 * with the new list of potential candidates.  Without
479 			 * this list pointer, only the first expansion is
480 			 * provided.  NOTE, that two $ISLIST expansions within
481 			 * the same path aren't supported.
482 			 */
483 			if ((omit & PN_TKN_ISALIST) || isaflag++)
484 				ok = 0;
485 			else
486 				ok = 1;
487 
488 			if (ok && (isa == 0))
489 				isa = conv_isalist();
490 
491 			if (ok && isa && isa->isa_listsz) {
492 				size_t	no, mlen, tlen, hlen = olen - 1;
493 				char	*lptr;
494 				Isa_opt *opt = isa->isa_opt;
495 
496 				if ((nlen += opt->isa_namesz) < PATH_MAX) {
497 					(void) strncpy(nptr,  opt->isa_name,
498 					    opt->isa_namesz);
499 					nptr = nptr + opt->isa_namesz;
500 					olen += MSG_TKN_ISALIST_SIZE;
501 					optr += MSG_TKN_ISALIST_SIZE;
502 					_flags |= PN_TKN_ISALIST;
503 				} else {
504 					eprintf(lml, ERR_FATAL,
505 					    MSG_INTL(MSG_ERR_EXPAND1),
506 					    NAME(lmp), oname);
507 					return (0);
508 				}
509 
510 				if (list) {
511 					tlen = *len - olen;
512 					mlen = ((hlen + tlen) *
513 					    (isa->isa_optno - 1)) +
514 					    isa->isa_listsz - opt->isa_namesz +
515 					    strlen(*list);
516 					if ((_list = lptr = malloc(mlen)) == 0)
517 						return (0);
518 
519 					for (no = 1, opt++; no < isa->isa_optno;
520 					    no++, opt++) {
521 						(void) strncpy(lptr, *name,
522 						    hlen);
523 						lptr = lptr + hlen;
524 						(void) strncpy(lptr,
525 						    opt->isa_name,
526 						    opt->isa_namesz);
527 						lptr = lptr + opt->isa_namesz;
528 						(void) strncpy(lptr, optr,
529 						    tlen);
530 						lptr = lptr + tlen;
531 						*lptr++ = ':';
532 					}
533 					if (**list)
534 						(void) strcpy(lptr, *list);
535 					else
536 						*--lptr = '\0';
537 				}
538 			}
539 
540 		} else if (strncmp(optr, MSG_ORIG(MSG_TKN_HWCAP),
541 		    MSG_TKN_HWCAP_SIZE) == 0) {
542 			char	*bptr = nptr - 1;
543 			char	*eptr = optr + MSG_TKN_HWCAP_SIZE;
544 			token = (char *)MSG_ORIG(MSG_TKN_HWCAP);
545 
546 			/*
547 			 * $HWCAP expansion required.  For compatibility with
548 			 * older environments, only expand this token when hard-
549 			 * ware capability information is available.   This
550 			 * expansion is only allowed for non-simple pathnames
551 			 * (must contain a '/'), with the token itself being the
552 			 * last element of the path.  Therefore, all we need do
553 			 * is test the existence of the string "/$HWCAP\0".
554 			 */
555 			if (((omit & PN_TKN_HWCAP) == 0) &&
556 			    (rtld_flags2 & RT_FL2_HWCAP) &&
557 			    ((bptr > _name) && (*bptr == '/') &&
558 			    ((*eptr == '\0') || (*eptr == ':')))) {
559 				/*
560 				 * Decrement the present pointer so that the
561 				 * directories trailing "/" gets nuked later.
562 				 */
563 				nptr--, nlen--;
564 				olen += MSG_TKN_HWCAP_SIZE;
565 				optr += MSG_TKN_HWCAP_SIZE;
566 				_flags |= PN_TKN_HWCAP;
567 			}
568 
569 		} else {
570 			/*
571 			 * If reserved token was not found, copy the
572 			 * character.
573 			 */
574 			*nptr++ = '$';
575 			nlen++;
576 		}
577 
578 		/*
579 		 * If reserved token was found, and could not be expanded,
580 		 * diagnose the error condition.
581 		 */
582 		if (token) {
583 			if (_flags)
584 				flags |= _flags;
585 			else {
586 				char	buf[PATH_MAX], *str;
587 
588 				/*
589 				 * Note, the original string we're expanding
590 				 * might contain a number of ':' separated
591 				 * paths.  Isolate the path we're processing to
592 				 * provide a more precise error diagnostic.
593 				 */
594 				if (str = strchr(oname, ':')) {
595 					size_t	slen = str - oname;
596 
597 					(void) strncpy(buf, oname, slen);
598 					buf[slen] = '\0';
599 					str = buf;
600 				} else
601 					str = oname;
602 
603 				eprintf(lml, ERR_FATAL,
604 				    MSG_INTL(MSG_ERR_EXPAND2), NAME(lmp),
605 				    str, token);
606 				return (0);
607 			}
608 		}
609 		_optr = optr;
610 	}
611 
612 	/*
613 	 * First make sure the current length is shorter than PATH_MAX.  We may
614 	 * arrive here if the given path contains '$' characters which are not
615 	 * the lead of a reserved token.
616 	 */
617 	if (nlen >= PATH_MAX) {
618 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ERR_EXPAND1), NAME(lmp),
619 		    oname);
620 		return (0);
621 	}
622 
623 	/*
624 	 * If any ISALIST processing has occurred not only do we return the
625 	 * expanded node we're presently working on, but we can also update the
626 	 * remaining list so that it is effectively prepended with this node
627 	 * expanded to all remaining ISALIST options.  Note that we can only
628 	 * handle one ISALIST per node.  For more than one ISALIST to be
629 	 * processed we'd need a better algorithm than above to replace the
630 	 * newly generated list.  Whether we want to encourage the number of
631 	 * pathname permutations this would provide is another question. So, for
632 	 * now if more than one ISALIST is encountered we return the original
633 	 * node untouched.
634 	 */
635 	if (isa && isaflag) {
636 		if (isaflag == 1) {
637 			if (list)
638 				*list = _list;
639 		} else {
640 			flags &= ~PN_TKN_ISALIST;
641 
642 			if ((nptr = calloc(1, (*len + 1))) == 0)
643 				return (0);
644 			(void) strncpy(nptr, *name, *len);
645 			*name = nptr;
646 
647 			return (TKN_NONE);
648 		}
649 	}
650 
651 	/*
652 	 * Copy any remaining string. Terminate the new string with a null as
653 	 * this string can be displayed via debugging diagnostics.
654 	 */
655 	if ((_len = (optr - _optr)) != 0) {
656 		if ((nlen += _len) < PATH_MAX) {
657 			(void) strncpy(nptr, _optr, _len);
658 			nptr = nptr + _len;
659 		} else {
660 			eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ERR_EXPAND1),
661 			    NAME(lmp), oname);
662 			return (0);
663 		}
664 	}
665 	*nptr = '\0';
666 
667 	/*
668 	 * A path that has been expanded, is typically used to create full
669 	 * pathnames for objects that will be opened.  The final pathname is
670 	 * resolved to simplify it, and set the stage for possible $ORIGIN
671 	 * processing.  Therefore, it's usually unnecessary to resolve the path
672 	 * at this point.  However, if a configuration file, containing
673 	 * directory information is in use, then we might need to lookup this
674 	 * path in the configuration file.  To keep the number of pathname
675 	 * resolutions to a minimum, only resolve paths that contain "./".  The
676 	 * use of "$ORIGIN/../lib" will probably only match a configuration file
677 	 * entry after resolution.
678 	 */
679 	if (list && ((rtld_flags & (RT_FL_DIRCFG | RT_FL_EXECNAME)) ==
680 	    (RT_FL_DIRCFG | RT_FL_EXECNAME)) && (flags & TKN_DOTSLASH)) {
681 		int	len;
682 
683 		if ((len = resolvepath(_name, _name, (PATH_MAX - 1))) >= 0) {
684 			nlen = (size_t)len;
685 			_name[nlen] = '\0';
686 		}
687 	}
688 
689 	/*
690 	 * Allocate permanent storage for the new string and return to the user.
691 	 */
692 	if ((nptr = malloc(nlen + 1)) == 0)
693 		return (0);
694 	(void) strcpy(nptr, _name);
695 	*name = nptr;
696 	*len = nlen;
697 
698 	/*
699 	 * Return an indication of any token expansion that may have occurred.
700 	 * Under security, any pathname expanded with the $ORIGIN token must be
701 	 * validated against any registered secure directories.
702 	 */
703 	return (flags ? flags : TKN_NONE);
704 }
705 
706 /*
707  * Determine whether a pathname is secure.
708  */
709 static int
710 is_path_secure(char *opath, Rt_map *clmp, uint_t info, uint_t flags)
711 {
712 	Pnode	*sdir = LM_SECURE_DIRS(LIST(clmp)->lm_head);
713 	char	buffer[PATH_MAX], *npath;
714 	Lm_list	*lml;
715 
716 	/*
717 	 * If a pathname originates from a configuration file, use it.  The use
718 	 * of a configuration file is already validated for secure applications,
719 	 * so if we're using a configuration file, we must be able to use all
720 	 * that it defines.
721 	 */
722 	if (info & LA_SER_CONFIG)
723 		return (1);
724 
725 	if ((info & LA_SER_MASK) == 0) {
726 		char	*str;
727 
728 		/*
729 		 * If the pathname specifies a file (rather than a directory),
730 		 * peel off the file before making the comparison.
731 		 */
732 		str = strrchr(opath, '/');
733 
734 		/*
735 		 * A simple filename (one containing no "/") is fine, as this
736 		 * will be combined with search paths to determine the complete
737 		 * path.  Other paths are checked:
738 		 *
739 		 *   .	a full path (one starting with "/") is fine, provided
740 		 *	it isn't a preload/audit path.
741 		 *   .  any $ORIGIN expansion
742 		 *   .	any relative path
743 		 */
744 		if (((str == 0) || ((*opath == '/') && (str != opath) &&
745 		    ((info & PN_FLG_EXTLOAD) == 0))) &&
746 		    ((flags & PN_TKN_ORIGIN) == 0))
747 			return (1);
748 
749 		if (str == opath)
750 			npath = (char *)MSG_ORIG(MSG_STR_SLASH);
751 		else {
752 			size_t	size;
753 
754 			if ((size = str - opath) >= PATH_MAX)
755 				return (0);
756 
757 			(void) strncpy(buffer, opath, size);
758 			buffer[size] = '\0';
759 			npath = buffer;
760 		}
761 	} else {
762 		/*
763 		 * A search path, i.e., RPATH, configuration file path, etc. is
764 		 * used as is.  Exceptions to this are:
765 		 *
766 		 *   .	LD_LIBRARY_PATH
767 		 *   .	any $ORIGIN expansion
768 		 *   .	any relative path
769 		 */
770 		if (((info & LA_SER_LIBPATH) == 0) && (*opath == '/') &&
771 		    ((flags & PN_TKN_ORIGIN) == 0))
772 			return (1);
773 
774 		npath = (char *)opath;
775 	}
776 
777 	while (sdir) {
778 		if (strcmp(npath, sdir->p_name) == 0)
779 			return (1);
780 		sdir = sdir->p_next;
781 	}
782 
783 	lml = LIST(clmp);
784 
785 	/*
786 	 * The path is insecure, so depending on the caller, provide a
787 	 * diagnostic.  Preloaded, or audit libraries generate a warning, as
788 	 * the process will run without them.
789 	 */
790 	if (info & PN_FLG_EXTLOAD) {
791 		if (lml->lm_flags & LML_FLG_TRC_ENABLE) {
792 			if ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0)
793 				(void) printf(MSG_INTL(MSG_LDD_FIL_ILLEGAL),
794 				    opath);
795 		} else
796 			eprintf(lml, ERR_WARNING, MSG_INTL(MSG_SEC_ILLEGAL),
797 			    opath);
798 
799 		return (0);
800 	}
801 
802 	/*
803 	 * Explicit file references are fatal.
804 	 */
805 	if ((info & LA_SER_MASK) == 0) {
806 		if (lml->lm_flags & LML_FLG_TRC_ENABLE) {
807 			/* BEGIN CSTYLED */
808 			if ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0) {
809 			    if (lml->lm_flags &
810 				(LML_FLG_TRC_VERBOSE | LML_FLG_TRC_SEARCH))
811 				    (void) printf(MSG_INTL(MSG_LDD_FIL_FIND),
812 					opath, NAME(clmp));
813 
814 			    if (((rtld_flags & RT_FL_SILENCERR) == 0) ||
815 				(lml->lm_flags & LML_FLG_TRC_VERBOSE))
816 				    (void) printf(MSG_INTL(MSG_LDD_FIL_ILLEGAL),
817 					opath);
818 			}
819 			/* END CSTYLED */
820 		} else
821 			eprintf(lml, ERR_FATAL, MSG_INTL(MSG_SYS_OPEN), opath,
822 			    strerror(EACCES));
823 	} else {
824 		/*
825 		 * Search paths.
826 		 */
827 		DBG_CALL(Dbg_libs_ignore(lml, opath));
828 		if ((lml->lm_flags & LML_FLG_TRC_SEARCH) &&
829 		    ((FLAGS1(clmp) & FL1_RT_LDDSTUB) == 0))
830 			(void) printf(MSG_INTL(MSG_LDD_PTH_IGNORE), opath);
831 	}
832 	return (0);
833 }
834 
835 /*
836  * Determine whether a path already exists within the callers Pnode list.
837  */
838 inline static uint_t
839 is_path_unique(Pnode *pnp, const char *path)
840 {
841 	for (; pnp; pnp = pnp->p_next) {
842 		if (pnp->p_len && (strcmp(pnp->p_name, path) == 0))
843 			return (PN_FLG_DUPLICAT);
844 	}
845 	return (0);
846 }
847 
848 /*
849  * Expand one or more pathnames.  This routine is called for all path strings,
850  * i.e., NEEDED, rpaths, default search paths, configuration file search paths,
851  * filtees, etc.  The path may be a single pathname, or a colon separated list
852  * of pathnames.  Each individual pathname is processed for possible reserved
853  * token expansion.  All string nodes are maintained in allocated memory
854  * (regardless of whether they are constant (":"), or token expanded) to
855  * simplify pnode removal.
856  *
857  * The info argument passes in auxiliary information regarding the callers
858  * intended use of the pathnames.  This information may be maintained in the
859  * pnode element produced to describe the pathname (i.e., LA_SER_LIBPATH etc.),
860  * or may be used to determine additional security or diagnostic processing.
861  */
862 Pnode *
863 expand_paths(Rt_map *clmp, const char *list, uint_t orig, uint_t omit)
864 {
865 	char	*str, *olist = 0, *nlist = (char *)list;
866 	Pnode	*pnp, *npnp, *opnp;
867 	int	fnull = FALSE;	/* TRUE if empty final path segment seen */
868 	uint_t	unique = 0;
869 
870 	for (pnp = opnp = 0, str = nlist; *nlist || fnull; str = nlist) {
871 		char	*ostr;
872 		size_t	len, olen;
873 		uint_t	tkns = 0;
874 
875 		if (*nlist == ';')
876 			++nlist, ++str;
877 		if ((*nlist == ':') || fnull) {
878 			/* If not a final null segment, check following one */
879 			fnull = !(fnull || *(nlist + 1));
880 
881 			if (*nlist)
882 				nlist++;
883 
884 			/*
885 			 * When the shell sees a null PATH segment, it
886 			 * treats it as if it were the cwd (.). We mimic
887 			 * this behavior for LD_LIBRARY_PATH and runpaths
888 			 * (mainly for backwards compatibility with previous
889 			 * behavior). For other paths, this makes no sense,
890 			 * so we simply ignore the segment.
891 			 */
892 			if (!(orig & (LA_SER_LIBPATH | LA_SER_RUNPATH)))
893 				continue; /* Process next segment */
894 
895 			if ((str = strdup(MSG_ORIG(MSG_FMT_CWD))) == NULL)
896 				return (NULL);
897 			len = MSG_FMT_CWD_SIZE;
898 
899 		} else {
900 			char	*elist;
901 
902 			len = 0;
903 			while (*nlist && (*nlist != ':') && (*nlist != ';')) {
904 				nlist++, len++;
905 			}
906 
907 			/* Check for a following final null segment */
908 			fnull = (*nlist == ':') && !*(nlist + 1);
909 
910 			if (*nlist)
911 				nlist++;
912 
913 			/*
914 			 * Expand the captured string.  Besides expanding the
915 			 * present path/file entry, we may have a new list to
916 			 * deal with (ISALIST expands to multiple new entries).
917 			 */
918 			elist = nlist;
919 			ostr = str;
920 			olen = len;
921 			if ((tkns = expand(&str, &len, &elist, orig, omit,
922 			    clmp)) == 0)
923 				continue;
924 
925 			if (elist != nlist) {
926 				if (olist)
927 					free(olist);
928 				nlist = olist = elist;
929 			}
930 		}
931 
932 		/*
933 		 * If this a secure application, validation of the expanded
934 		 * pathname may be necessary.
935 		 */
936 		if (rtld_flags & RT_FL_SECURE) {
937 			if (is_path_secure(str, clmp, orig, tkns) == 0) {
938 				free(str);
939 				continue;
940 			}
941 		}
942 
943 		/*
944 		 * If required, ensure that the string is unique.  For search
945 		 * paths such as LD_LIBRARY_PATH, users often inherit multiple
946 		 * paths which result in unnecessary duplication.  Note, if
947 		 * we're debugging, any duplicate entry is retained and flagged
948 		 * so that the entry can be diagnosed later as part of unused
949 		 * processing.
950 		 */
951 		if (orig & PN_FLG_UNIQUE) {
952 			Word	tracing;
953 
954 			tracing = LIST(clmp)->lm_flags &
955 			    (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED);
956 			unique = is_path_unique(pnp, str);
957 
958 			/*
959 			 * Note, use the debug strings rpl_debug and prm_debug
960 			 * as an indicator that debugging has been requested,
961 			 * rather than DBG_ENABLE(), as the initial use of
962 			 * LD_LIBRARY_PATH occurs in preparation for loading
963 			 * our debugging library.
964 			 */
965 			if ((unique == PN_FLG_DUPLICAT) && (tracing == 0) &&
966 			    (rpl_debug == 0) && (prm_debug == 0)) {
967 				free(str);
968 				continue;
969 			}
970 		}
971 
972 		/*
973 		 * Allocate a new Pnode for this string.
974 		 */
975 		if ((npnp = calloc(1, sizeof (Pnode))) == 0) {
976 			free(str);
977 			return (NULL);
978 		}
979 		if (opnp == 0)
980 			pnp = npnp;
981 		else
982 			opnp->p_next = npnp;
983 
984 		if (tkns & PN_TKN_MASK) {
985 			char	*oname;
986 
987 			/*
988 			 * If this is a pathname, and any token expansion
989 			 * occurred, maintain the original string for possible
990 			 * diagnostic use.
991 			 */
992 			if ((oname = malloc(olen + 1)) == 0) {
993 				free(str);
994 				return (NULL);
995 			}
996 			(void) strncpy(oname, ostr, olen);
997 			oname[olen] = '\0';
998 			npnp->p_oname = oname;
999 		}
1000 		npnp->p_name = str;
1001 		npnp->p_len = len;
1002 		npnp->p_orig = (orig & LA_SER_MASK) | unique |
1003 		    (tkns & PN_TKN_MASK);
1004 
1005 		opnp = npnp;
1006 	}
1007 
1008 	if (olist)
1009 		free(olist);
1010 
1011 	return (pnp);
1012 }
1013