xref: /illumos-gate/usr/src/cmd/sgs/rtld/common/setup.c (revision 7a6d80f1660abd4755c68cbd094d4a914681d26e)
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) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 /*
27  *	Copyright (c) 1988 AT&T
28  *	  All Rights Reserved
29  */
30 /*
31  * Copyright (c) 2012, Joyent, Inc.  All rights reserved.
32  * Copyright 2022 Oxide Computer Company
33  */
34 
35 /*
36  * Run time linker common setup.
37  *
38  * Called from _setup to get the process going at startup.
39  */
40 
41 #include	<stdlib.h>
42 #include	<fcntl.h>
43 #include	<stdio.h>
44 #include	<sys/types.h>
45 #include	<sys/stat.h>
46 #include	<sys/mman.h>
47 #include	<string.h>
48 #include	<unistd.h>
49 #include	<dlfcn.h>
50 #include	<sys/sysconfig.h>
51 #include	<sys/auxv.h>
52 #include	<debug.h>
53 #include	<conv.h>
54 #include	"_rtld.h"
55 #include	"_audit.h"
56 #include	"_elf.h"
57 #include	"msg.h"
58 
59 
60 extern int	_end, _edata, _etext;
61 extern void	_init(void);
62 extern int	_brk_unlocked(void *);
63 
64 /* needed for _brk_unlocked() */
65 void *_nd = &_end;
66 
67 /*
68  * Counters that are incremented every time an object is mapped/unmapped.
69  *
70  * Note that exec() will usually map 2 objects before we receive control,
71  * but this can be 1 if ld.so.1 is executed directly. We count one of these
72  * here, and add another as necessary in setup().
73  */
74 u_longlong_t	cnt_map = 1;
75 u_longlong_t	cnt_unmap = 0;
76 
77 
78 /*
79  * Define for the executable's interpreter.
80  * Usually it is ld.so.1, but for the first release of ICL binaries
81  * it is libc.so.1.  We keep this information so that we don't end
82  * up mapping libc twice if it is the interpreter.
83  */
84 static Interp _interp;
85 
86 /*
87  * LD_PRELOAD objects.
88  */
89 static int
90 preload(const char *str, Rt_map *mlmp, Rt_map **clmp)
91 {
92 	Alist		*palp = NULL;
93 	char		*objs, *ptr, *next;
94 	Word		lmflags = lml_main.lm_flags;
95 	int		lddstub;
96 
97 	DBG_CALL(Dbg_util_nl(&lml_main, DBG_NL_STD));
98 
99 	if ((objs = strdup(str)) == NULL)
100 		return (0);
101 
102 	/*
103 	 * Determine if we've been called from lddstub.
104 	 */
105 	lddstub = (lmflags & LML_FLG_TRC_ENABLE) &&
106 	    (FLAGS1(*clmp) & FL1_RT_LDDSTUB);
107 
108 
109 	for (ptr = strtok_r(objs, MSG_ORIG(MSG_STR_DELIMIT), &next);
110 	    ptr != NULL;
111 	    ptr = strtok_r(NULL, MSG_ORIG(MSG_STR_DELIMIT), &next)) {
112 		Rt_map	*nlmp = NULL;
113 		uint_t	flags;
114 
115 		DBG_CALL(Dbg_file_preload(&lml_main, ptr));
116 
117 		/*
118 		 * Establish the flags for loading each object.  If we're
119 		 * called via lddstub, then the first preloaded object is the
120 		 * object being inspected by ldd(1).  This object should not be
121 		 * marked as an interposer, as this object is intended to act
122 		 * as the target object of the process.
123 		 */
124 		if (lddstub)
125 			flags = FLG_RT_PRELOAD;
126 		else
127 			flags = (FLG_RT_PRELOAD | FLG_RT_OBJINTPO);
128 
129 		/*
130 		 * If this a secure application, then preload errors are
131 		 * reduced to warnings, as the errors are non-fatal.
132 		 */
133 		if (rtld_flags & RT_FL_SECURE)
134 			rtld_flags2 |= RT_FL2_FTL2WARN;
135 		if (expand_paths(*clmp, ptr, &palp, AL_CNT_NEEDED,
136 		    PD_FLG_EXTLOAD, 0) != 0)
137 			nlmp = load_one(&lml_main, ALIST_OFF_DATA, palp, *clmp,
138 			    MODE(mlmp), flags, 0, NULL);
139 		remove_alist(&palp, 0);
140 		if (rtld_flags & RT_FL_SECURE)
141 			rtld_flags2 &= ~RT_FL2_FTL2WARN;
142 		if (nlmp && (bind_one(*clmp, nlmp, BND_NEEDED) == 0))
143 			nlmp = NULL;
144 
145 		if (lddstub && nlmp) {
146 			lddstub = 0;
147 
148 			/*
149 			 * Fabricate a binding between the target shared object
150 			 * and lddstub so that the target object isn't called
151 			 * out from unused() processing.
152 			 */
153 			if (lmflags &
154 			    (LML_FLG_TRC_UNREF | LML_FLG_TRC_UNUSED)) {
155 				if (bind_one(*clmp, nlmp, BND_REFER) == 0)
156 					nlmp = NULL;
157 			}
158 
159 			/*
160 			 * By identifying lddstub as the caller, several
161 			 * confusing ldd() diagnostics get suppressed.  These
162 			 * diagnostics would reveal how the target shared object
163 			 * was found from lddstub.  Now that the real target is
164 			 * loaded, identify the target as the caller so that all
165 			 * ldd() diagnostics are enabled for subsequent objects.
166 			 */
167 			if (nlmp)
168 				*clmp = nlmp;
169 		}
170 
171 		/*
172 		 * If no error occurred with loading this object, indicate that
173 		 * this link-map list contains an interposer.
174 		 */
175 		if (nlmp == NULL) {
176 			if ((lmflags & LML_FLG_TRC_ENABLE) ||
177 			    (rtld_flags & RT_FL_SECURE))
178 				continue;
179 			else
180 				return (0);
181 		}
182 		if (flags & FLG_RT_OBJINTPO)
183 			lml_main.lm_flags |= LML_FLG_INTRPOSE;
184 
185 	}
186 
187 	free(palp);
188 	free(objs);
189 	return (1);
190 }
191 
192 Rt_map *
193 setup(char **envp, auxv_t *auxv, Word _flags, char *_platform, int _syspagsz,
194     char *_rtldname, ulong_t ld_base, ulong_t interp_base, int fd, Phdr *phdr,
195     char *execname, char **argv, uid_t uid, uid_t euid, gid_t gid, gid_t egid,
196     int auxflags, uint_t *hwcap)
197 {
198 	Rt_map			*rlmp, *mlmp, *clmp, **tobj = NULL;
199 	Ehdr			*ehdr;
200 	rtld_stat_t		status;
201 	int			features = 0, ldsoexec = 0;
202 	size_t			eaddr, esize;
203 	char			*str, *argvname;
204 	Word			lmflags;
205 	mmapobj_result_t	*mpp;
206 	Fdesc			fdr = { 0 }, fdm = { 0 };
207 	Rej_desc		rej = { 0 };
208 	APlist			*ealp = NULL;
209 
210 	/*
211 	 * Now that ld.so has relocated itself, initialize our own 'environ' so
212 	 * as to establish an address suitable for any libc requirements.
213 	 */
214 	_environ = (char **)((ulong_t)auxv - sizeof (char *));
215 	_init();
216 	_environ = envp;
217 
218 	/*
219 	 * Establish a base time.  Total time diagnostics start from entering
220 	 * ld.so.1 here, however the base time is reset each time the ld.so.1
221 	 * is re-entered.  Note also, there will be a large time associated
222 	 * with the first diagnostic from ld.so.1, as bootstrapping ld.so.1
223 	 * and establishing the liblddbg infrastructure takes some time.
224 	 */
225 	(void) gettimeofday(&DBG_TOTALTIME, NULL);
226 	DBG_DELTATIME = DBG_TOTALTIME;
227 
228 	/*
229 	 * Determine how ld.so.1 has been executed.
230 	 */
231 	if ((fd == -1) && (phdr == NULL)) {
232 		/*
233 		 * If we received neither the AT_EXECFD nor the AT_PHDR aux
234 		 * vector, ld.so.1 must have been invoked directly from the
235 		 * command line.
236 		 */
237 		ldsoexec = 1;
238 
239 		/*
240 		 * AT_SUN_EXECNAME provides the most precise name, if it is
241 		 * available, otherwise fall back to argv[0].  At this time,
242 		 * there is no process name.
243 		 */
244 		if (execname)
245 			rtldname = execname;
246 		else if (argv[0])
247 			rtldname = argv[0];
248 		else
249 			rtldname = (char *)MSG_INTL(MSG_STR_UNKNOWN);
250 	} else {
251 		/*
252 		 * Otherwise, we have a standard process.  AT_SUN_EXECNAME
253 		 * provides the most precise name, if it is available,
254 		 * otherwise fall back to argv[0].  Provided the application
255 		 * is already mapped, the process is the application, so
256 		 * simplify the application name for use in any diagnostics.
257 		 */
258 		if (execname)
259 			argvname = execname;
260 		else if (argv[0])
261 			argvname = execname = argv[0];
262 		else
263 			argvname = execname = (char *)MSG_INTL(MSG_STR_UNKNOWN);
264 
265 		if (fd == -1) {
266 			if ((str = strrchr(argvname, '/')) != NULL)
267 				procname = ++str;
268 			else
269 				procname = argvname;
270 		}
271 
272 		/*
273 		 * At this point, we don't know the runtime linkers full path
274 		 * name.  The _rtldname passed to us is the SONAME of the
275 		 * runtime linker, which is typically /lib/ld.so.1 no matter
276 		 * what the full path is.   Use this for now, we'll reset the
277 		 * runtime linkers name once the application is analyzed.
278 		 */
279 		if (_rtldname) {
280 			if ((str = strrchr(_rtldname, '/')) != NULL)
281 				rtldname = ++str;
282 			else
283 				rtldname = _rtldname;
284 		} else
285 			rtldname = (char *)MSG_INTL(MSG_STR_UNKNOWN);
286 
287 		/* exec() brought in two objects for us. Count the second one */
288 		cnt_map++;
289 	}
290 
291 	/*
292 	 * Initialize any global variables.
293 	 */
294 	at_flags = _flags;
295 
296 	if ((org_scapset->sc_plat = _platform) != NULL)
297 		org_scapset->sc_platsz = strlen(_platform);
298 
299 	if (org_scapset->sc_plat == NULL)
300 		platform_name(org_scapset);
301 	if (org_scapset->sc_mach == NULL)
302 		machine_name(org_scapset);
303 
304 	/*
305 	 * If pagesize is unspecified find its value.
306 	 */
307 	if ((syspagsz = _syspagsz) == 0)
308 		syspagsz = _sysconfig(_CONFIG_PAGESIZE);
309 
310 	/*
311 	 * Add the unused portion of the last data page to the free space list.
312 	 * The page size must be set before doing this.  Here, _end refers to
313 	 * the end of the runtime linkers bss.  Note that we do not use the
314 	 * unused data pages from any included .so's to supplement this free
315 	 * space as badly behaved .os's may corrupt this data space, and in so
316 	 * doing ruin our data.
317 	 */
318 	eaddr = S_DROUND((size_t)&_end);
319 	esize = eaddr % syspagsz;
320 	if (esize) {
321 		esize = syspagsz - esize;
322 		addfree((void *)eaddr, esize);
323 	}
324 
325 	/*
326 	 * Establish initial link-map list flags, and link-map list alists.
327 	 */
328 	if (alist_append(&lml_main.lm_lists, NULL, sizeof (Lm_cntl),
329 	    AL_CNT_LMLISTS) == NULL)
330 		return (0);
331 	lml_main.lm_flags |= LML_FLG_BASELM;
332 	lml_main.lm_lmid = LM_ID_BASE;
333 	lml_main.lm_lmidstr = (char *)MSG_ORIG(MSG_LMID_BASE);
334 
335 	if (alist_append(&lml_rtld.lm_lists, NULL, sizeof (Lm_cntl),
336 	    AL_CNT_LMLISTS) == NULL)
337 		return (0);
338 	lml_rtld.lm_flags |= (LML_FLG_RTLDLM | LML_FLG_HOLDLOCK);
339 	lml_rtld.lm_tflags |= LML_TFLG_NOAUDIT;
340 	lml_rtld.lm_lmid = LM_ID_LDSO;
341 	lml_rtld.lm_lmidstr = (char *)MSG_ORIG(MSG_LMID_LDSO);
342 
343 	/*
344 	 * Determine whether we have a secure executable.
345 	 */
346 	security(uid, euid, gid, egid, auxflags);
347 
348 	/*
349 	 * Make an initial pass of environment variables to pick off those
350 	 * related to locale processing.  At the same time, collect and save
351 	 * any LD_XXXX variables for later processing.  Note that this later
352 	 * processing will be skipped if ld.so.1 is invoked from the command
353 	 * line with -e LD_NOENVIRON.
354 	 */
355 	if (envp && (readenv_user((const char **)envp, &ealp) == 1))
356 		return (0);
357 
358 	/*
359 	 * If ld.so.1 has been invoked directly, process its arguments.
360 	 */
361 	if (ldsoexec) {
362 		/*
363 		 * Process any arguments that are specific to ld.so.1, and
364 		 * reorganize the process stack to effectively remove ld.so.1
365 		 * from the stack.  Reinitialize the environment pointer, as
366 		 * this pointer may have been shifted after skipping ld.so.1's
367 		 * arguments.
368 		 */
369 		if (rtld_getopt(argv, &envp, &auxv, &(lml_main.lm_flags),
370 		    &(lml_main.lm_tflags)) == 1) {
371 			eprintf(&lml_main, ERR_NONE, MSG_INTL(MSG_USG_BADOPT));
372 			return (0);
373 		}
374 		_environ = envp;
375 
376 		/*
377 		 * Open the object that ld.so.1 is to execute.
378 		 */
379 		argvname = execname = argv[0];
380 
381 		if ((fd = open(argvname, O_RDONLY)) == -1) {
382 			int	err = errno;
383 			eprintf(&lml_main, ERR_FATAL, MSG_INTL(MSG_SYS_OPEN),
384 			    argvname, strerror(err));
385 			return (0);
386 		}
387 	}
388 
389 	/*
390 	 * Having processed any ld.so.1 command line options, return to process
391 	 * any LD_XXXX environment variables.
392 	 */
393 	if (ealp) {
394 		if (((rtld_flags & RT_FL_NOENVIRON) == 0) &&
395 		    (procenv_user(ealp, &(lml_main.lm_flags),
396 		    &(lml_main.lm_tflags)) == 1))
397 			return (0);
398 		free(ealp);
399 	}
400 
401 	/*
402 	 * Initialize a hardware capability descriptor for use in comparing
403 	 * each loaded object.  The aux vector must provide AF_SUN_HWCAPVERIFY,
404 	 * as prior to this setting any hardware capabilities that were found
405 	 * could not be relied upon.
406 	 */
407 	if (auxflags & AF_SUN_HWCAPVERIFY) {
408 		rtld_flags2 |= RT_FL2_HWCAP;
409 		org_scapset->sc_hw_1 = (Xword)hwcap[0];
410 		org_scapset->sc_hw_2 = (Xword)hwcap[1];
411 		org_scapset->sc_hw_3 = (Xword)hwcap[2];
412 	}
413 
414 	/*
415 	 * Create a mapping descriptor for ld.so.1.  We can determine our
416 	 * two segments information from known symbols.
417 	 */
418 	if ((mpp = calloc(2, sizeof (mmapobj_result_t))) == NULL)
419 		return (0);
420 	mpp[0].mr_addr = (caddr_t)M_PTRUNC(ld_base);
421 	mpp[0].mr_msize = (caddr_t)&_etext - mpp[0].mr_addr;
422 	mpp[0].mr_fsize = mpp[0].mr_msize;
423 	mpp[0].mr_prot = (PROT_READ | PROT_EXEC);
424 
425 	mpp[1].mr_addr = (caddr_t)M_PTRUNC((uintptr_t)&r_debug);
426 	mpp[1].mr_msize = (caddr_t)&_end - mpp[1].mr_addr;
427 	mpp[1].mr_fsize = (caddr_t)&_edata - mpp[1].mr_addr;
428 	mpp[1].mr_prot = (PROT_READ | PROT_WRITE | PROT_EXEC);
429 
430 	if ((fdr.fd_nname = stravl_insert(_rtldname, 0, 0, 0)) == NULL)
431 		return (0);
432 	if ((rlmp = elf_new_lmp(&lml_rtld, ALIST_OFF_DATA, &fdr,
433 	    (Addr)mpp->mr_addr, (size_t)((uintptr_t)eaddr - (uintptr_t)ld_base),
434 	    NULL, NULL, NULL)) == NULL)
435 		return (0);
436 
437 	MMAPS(rlmp) = mpp;
438 	MMAPCNT(rlmp) = 2;
439 	PADSTART(rlmp) = (ulong_t)mpp[0].mr_addr;
440 	PADIMLEN(rlmp) = (ulong_t)mpp[0].mr_addr + (ulong_t)mpp[1].mr_addr +
441 	    (ulong_t)mpp[1].mr_msize;
442 
443 	MODE(rlmp) |= (RTLD_LAZY | RTLD_NODELETE | RTLD_GLOBAL | RTLD_WORLD);
444 	FLAGS(rlmp) |= (FLG_RT_ANALYZED | FLG_RT_RELOCED | FLG_RT_INITDONE |
445 	    FLG_RT_INITCLCT | FLG_RT_FINICLCT | FLG_RT_MODESET);
446 
447 	/*
448 	 * Initialize the runtime linkers information.
449 	 */
450 	interp = &_interp;
451 	interp->i_name = (char *)rtldname;
452 	interp->i_faddr = (caddr_t)ADDR(rlmp);
453 	ldso_plt_init(rlmp);
454 
455 	/*
456 	 * Map in the file, if exec has not already done so, or if the file
457 	 * was passed as an argument to an explicit execution of ld.so.1 from
458 	 * the command line.
459 	 */
460 	if (fd != -1) {
461 		/*
462 		 * Map the file.  Once the object is mapped we no longer need
463 		 * the file descriptor.
464 		 */
465 		(void) rtld_fstat(fd, &status);
466 		fdm.fd_oname = argvname;
467 		fdm.fd_ftp = map_obj(&lml_main, &fdm, status.st_size, argvname,
468 		    fd, &rej);
469 		(void) close(fd);
470 
471 		if (fdm.fd_ftp == NULL) {
472 			Conv_reject_desc_buf_t rej_buf;
473 
474 			eprintf(&lml_main, ERR_FATAL,
475 			    MSG_INTL(err_reject[rej.rej_type]), argvname,
476 			    conv_reject_desc(&rej, &rej_buf, M_MACH));
477 			return (0);
478 		}
479 
480 		/*
481 		 * Finish processing the loading of the file.
482 		 */
483 		if ((fdm.fd_nname = stravl_insert(argvname, 0, 0, 0)) == NULL)
484 			return (0);
485 		fdm.fd_dev = status.st_dev;
486 		fdm.fd_ino = status.st_ino;
487 
488 		if ((mlmp = load_file(&lml_main, ALIST_OFF_DATA, NULL, &fdm,
489 		    NULL)) == NULL)
490 			return (0);
491 
492 		/*
493 		 * We now have a process name for error diagnostics.
494 		 */
495 		if ((str = strrchr(argvname, '/')) != NULL)
496 			procname = ++str;
497 		else
498 			procname = argvname;
499 
500 		if (ldsoexec) {
501 			mmapobj_result_t	*mpp = MMAPS(mlmp);
502 			uint_t			mnum, mapnum = MMAPCNT(mlmp);
503 			void			*brkbase = NULL;
504 
505 			/*
506 			 * Since ld.so.1 was the primary executed object - the
507 			 * brk() base has not yet been initialized, we need to
508 			 * initialize it.  For an executable, initialize it to
509 			 * the end of the object.  For a shared object (ET_DYN)
510 			 * initialize it to the first page in memory.
511 			 */
512 			for (mnum = 0; mnum < mapnum; mnum++, mpp++)
513 				brkbase = mpp->mr_addr + mpp->mr_msize;
514 
515 			if (brkbase == NULL)
516 				brkbase = (void *)syspagsz;
517 
518 			if (_brk_unlocked(brkbase) == -1) {
519 				int	err = errno;
520 
521 				eprintf(&lml_main, ERR_FATAL,
522 				    MSG_INTL(MSG_SYS_BRK), argvname,
523 				    strerror(err));
524 				return (0);
525 			}
526 		}
527 	} else {
528 		if (phdr != NULL) {
529 			Phdr			*pptr;
530 			Off			i_offset = 0;
531 			Addr			base = 0;
532 			ulong_t			phsize;
533 			mmapobj_result_t	*mpp, *fmpp, *hmpp = NULL;
534 			uint_t			mapnum = 0;
535 			int			i;
536 			size_t			msize;
537 
538 			/*
539 			 * Using the executables phdr address determine the base
540 			 * address of the input file.  NOTE, this assumes the
541 			 * program headers and elf header are part of the same
542 			 * mapped segment.  Although this has held for many
543 			 * years now, it might be more flexible if the kernel
544 			 * gave use the ELF headers start address, rather than
545 			 * the Program headers.
546 			 *
547 			 * Determine from the ELF header if we're been called
548 			 * from a shared object or dynamic executable.  If the
549 			 * latter, then any addresses within the object are used
550 			 * as is.  Addresses within shared objects must be added
551 			 * to the process's base address.
552 			 */
553 			ehdr = (Ehdr *)((Addr)phdr - phdr->p_offset);
554 			phsize = ehdr->e_phentsize;
555 			if (ehdr->e_type == ET_DYN)
556 				base = (Addr)ehdr;
557 
558 			/*
559 			 * Allocate a mapping array to retain mapped segment
560 			 * information.
561 			 */
562 			if ((fmpp = mpp = calloc(ehdr->e_phnum,
563 			    sizeof (mmapobj_result_t))) == NULL)
564 				return (0);
565 
566 			/*
567 			 * Extract the needed information from the segment
568 			 * headers.
569 			 */
570 			for (i = 0, pptr = phdr; i < ehdr->e_phnum; i++) {
571 				if (pptr->p_type == PT_INTERP) {
572 					i_offset = pptr->p_offset;
573 					interp->i_faddr =
574 					    (caddr_t)interp_base;
575 				}
576 				if ((pptr->p_type == PT_LOAD) &&
577 				    (pptr->p_filesz || pptr->p_memsz)) {
578 					int	perm = (PROT_READ | PROT_EXEC);
579 					size_t	off;
580 
581 					if (i_offset && pptr->p_filesz &&
582 					    (i_offset >= pptr->p_offset) &&
583 					    (i_offset <=
584 					    (pptr->p_memsz + pptr->p_offset))) {
585 						interp->i_name = (char *)
586 						    pptr->p_vaddr + i_offset -
587 						    pptr->p_offset + base;
588 						i_offset = 0;
589 					}
590 
591 					if (pptr->p_flags & PF_W)
592 						perm |= PROT_WRITE;
593 
594 					/*
595 					 * Retain segments mapping info.  Round
596 					 * each segment to a page boundary, as
597 					 * this insures addresses are suitable
598 					 * for mprotect() if required.
599 					 */
600 					off = pptr->p_vaddr + base;
601 					if (hmpp == NULL) {
602 						hmpp = mpp;
603 						mpp->mr_addr = (caddr_t)ehdr;
604 					} else
605 						mpp->mr_addr = (caddr_t)off;
606 
607 					off -= (size_t)(uintptr_t)mpp->mr_addr;
608 					mpp->mr_msize = pptr->p_memsz + off;
609 					mpp->mr_fsize = pptr->p_filesz + off;
610 					mpp->mr_prot = perm;
611 
612 					mpp++, mapnum++;
613 				}
614 
615 				pptr = (Phdr *)((ulong_t)pptr + phsize);
616 			}
617 
618 			mpp--;
619 			msize = (size_t)(mpp->mr_addr + mpp->mr_msize) -
620 			    S_ALIGN((size_t)fmpp->mr_addr, syspagsz);
621 
622 			if ((fdm.fd_nname =
623 			    stravl_insert(execname, 0, 0, 0)) == NULL)
624 				return (0);
625 			if ((mlmp = elf_new_lmp(&lml_main, ALIST_OFF_DATA,
626 			    &fdm, (Addr)hmpp->mr_addr, msize,
627 			    NULL, NULL, NULL)) == NULL)
628 				return (0);
629 
630 			MMAPS(mlmp) = fmpp;
631 			MMAPCNT(mlmp) = mapnum;
632 			PADSTART(mlmp) = (ulong_t)fmpp->mr_addr;
633 			PADIMLEN(mlmp) = (ulong_t)fmpp->mr_addr +
634 			    (ulong_t)mpp->mr_addr + (ulong_t)mpp->mr_msize;
635 		}
636 	}
637 
638 	/*
639 	 * Establish the interpretors name as that defined within the initial
640 	 * object (executable).  This provides for ORIGIN processing of ld.so.1
641 	 * dependencies.  Note, the NAME() of the object remains that which was
642 	 * passed to us as the SONAME on execution.
643 	 */
644 	if (ldsoexec == 0) {
645 		size_t	len = strlen(interp->i_name);
646 
647 		if (expand(&interp->i_name, &len, 0, 0,
648 		    (PD_TKN_ISALIST | PD_TKN_CAP), rlmp) & PD_TKN_RESOLVED)
649 			fdr.fd_flags |= FLG_FD_RESOLVED;
650 	}
651 	fdr.fd_pname = interp->i_name;
652 	(void) fullpath(rlmp, &fdr);
653 
654 	/*
655 	 * The runtime linker acts as a filtee for various dl*() functions that
656 	 * are defined in libc (and libdl).  Make sure this standard name for
657 	 * the runtime linker is also registered in the FullPathNode AVL tree.
658 	 */
659 	(void) fpavl_insert(&lml_rtld, rlmp, _rtldname, 0);
660 
661 	/*
662 	 * Having established the true runtime linkers name, simplify the name
663 	 * for error diagnostics.
664 	 */
665 	if ((str = strrchr(PATHNAME(rlmp), '/')) != NULL)
666 		rtldname = ++str;
667 	else
668 		rtldname = PATHNAME(rlmp);
669 
670 	/*
671 	 * Expand the fullpath name of the application.  This typically occurs
672 	 * as a part of loading an object, but as the kernel probably mapped
673 	 * it in, complete this processing now.
674 	 */
675 	(void) fullpath(mlmp, 0);
676 
677 	/*
678 	 * Some troublesome programs will change the value of argv[0].  Dupping
679 	 * the process string protects us, and insures the string is left in
680 	 * any core files.
681 	 */
682 	if ((str = (char *)strdup(procname)) == NULL)
683 		return (0);
684 	procname = str;
685 
686 	FLAGS(mlmp) |= (FLG_RT_ISMAIN | FLG_RT_MODESET);
687 	FLAGS1(mlmp) |= FL1_RT_USED;
688 
689 	/*
690 	 * It's the responsibility of MAIN(crt0) to call it's _init and _fini
691 	 * section, therefore null out any INIT/FINI so that this object isn't
692 	 * collected during tsort processing.  And, if the application has no
693 	 * initarray or finiarray we can economize on establishing bindings.
694 	 */
695 	INIT(mlmp) = FINI(mlmp) = NULL;
696 	if ((INITARRAY(mlmp) == NULL) && (FINIARRAY(mlmp) == NULL))
697 		FLAGS1(mlmp) |= FL1_RT_NOINIFIN;
698 
699 	/*
700 	 * Identify lddstub if necessary.
701 	 */
702 	if (lml_main.lm_flags & LML_FLG_TRC_LDDSTUB)
703 		FLAGS1(mlmp) |= FL1_RT_LDDSTUB;
704 
705 	/*
706 	 * Retain our argument information for use in dlinfo.
707 	 */
708 	argsinfo.dla_argv = argv--;
709 	argsinfo.dla_argc = (long)*argv;
710 	argsinfo.dla_envp = envp;
711 	argsinfo.dla_auxv = auxv;
712 
713 	(void) enter(0);
714 
715 	/*
716 	 * Add our two main link-maps to the dynlm_list
717 	 */
718 	if (aplist_append(&dynlm_list, &lml_main, AL_CNT_DYNLIST) == NULL)
719 		return (0);
720 
721 	if (aplist_append(&dynlm_list, &lml_rtld, AL_CNT_DYNLIST) == NULL)
722 		return (0);
723 
724 	/*
725 	 * Reset the link-map counts for both lists.  The init count is used to
726 	 * track how many objects have pending init sections, this gets incre-
727 	 * mented each time an object is relocated.  Since ld.so.1 relocates
728 	 * itself, it's init count will remain zero.
729 	 * The object count is used to track how many objects have pending fini
730 	 * sections, as ld.so.1 handles its own fini we can zero its count.
731 	 */
732 	lml_main.lm_obj = 1;
733 	lml_rtld.lm_obj = 0;
734 
735 	/*
736 	 * Initialize debugger information structure.  Some parts of this
737 	 * structure were initialized statically.
738 	 */
739 	r_debug.rtd_rdebug.r_map = (Link_map *)lml_main.lm_head;
740 	r_debug.rtd_rdebug.r_ldsomap = (Link_map *)lml_rtld.lm_head;
741 	r_debug.rtd_rdebug.r_ldbase = r_debug.rtd_rdebug.r_ldsomap->l_addr;
742 	r_debug.rtd_dynlmlst = &dynlm_list;
743 
744 	/*
745 	 * Determine the dev/inode information for the executable to complete
746 	 * load_so() checking for those who might call dlopen(3c) on the
747 	 * executable .
748 	 */
749 	if (rtld_stat(PATHNAME(mlmp), &status) == 0) {
750 		STDEV(mlmp) = status.st_dev;
751 		STINO(mlmp) = status.st_ino;
752 	}
753 
754 	/*
755 	 * Initialize any configuration information.
756 	 */
757 	if (!(rtld_flags & RT_FL_NOCFG)) {
758 		if ((features = elf_config(mlmp)) == -1)
759 			return (0);
760 	}
761 
762 #if	defined(_ELF64)
763 	/*
764 	 * If this is a 64-bit process, determine whether this process has
765 	 * restricted the process address space to 32-bits.  Any dependencies
766 	 * that are restricted to a 32-bit address space can only be loaded if
767 	 * the executable has established this requirement.
768 	 */
769 	if (CAPSET(mlmp).sc_sf_1 & SF1_SUNW_ADDR32)
770 		rtld_flags2 |= RT_FL2_ADDR32;
771 #endif
772 	/*
773 	 * Establish any alternative capabilities, and validate this object
774 	 * if it defines it's own capabilities information.
775 	 */
776 	if (cap_alternative() == 0)
777 		return (0);
778 
779 	if (cap_check_lmp(mlmp, &rej) == 0) {
780 		if (lml_main.lm_flags & LML_FLG_TRC_ENABLE) {
781 			/* LINTED */
782 			(void) printf(MSG_INTL(ldd_warn[rej.rej_type]),
783 			    NAME(mlmp), rej.rej_str);
784 		} else {
785 			/* LINTED */
786 			eprintf(&lml_main, ERR_FATAL,
787 			    MSG_INTL(err_reject[rej.rej_type]),
788 			    NAME(mlmp), rej.rej_str);
789 			return (0);
790 		}
791 	}
792 
793 	/*
794 	 * Establish the modes of the initial object.  These modes are
795 	 * propagated to any preloaded objects and explicit shared library
796 	 * dependencies.
797 	 *
798 	 * If we're generating a configuration file using crle(1), remove
799 	 * any RTLD_NOW use, as we don't want to trigger any relocation proc-
800 	 * essing during crle(1)'s first past (this would just be unnecessary
801 	 * overhead).  Any filters are explicitly loaded, and thus RTLD_NOW is
802 	 * not required to trigger filter loading.
803 	 *
804 	 * Note, RTLD_NOW may have been established during analysis of the
805 	 * application had the application been built -z now.
806 	 */
807 	MODE(mlmp) |= (RTLD_NODELETE | RTLD_GLOBAL | RTLD_WORLD);
808 
809 	if (rtld_flags & RT_FL_CONFGEN) {
810 		MODE(mlmp) |= RTLD_CONFGEN;
811 		MODE(mlmp) &= ~RTLD_NOW;
812 		rtld_flags2 &= ~RT_FL2_BINDNOW;
813 	}
814 
815 	if ((MODE(mlmp) & RTLD_NOW) == 0) {
816 		if (rtld_flags2 & RT_FL2_BINDNOW)
817 			MODE(mlmp) |= RTLD_NOW;
818 		else
819 			MODE(mlmp) |= RTLD_LAZY;
820 	}
821 
822 	/*
823 	 * If debugging was requested initialize things now that any cache has
824 	 * been established.  A user can specify LD_DEBUG=help to discover the
825 	 * list of debugging tokens available without running the application.
826 	 * However, don't allow this setting from a configuration file.
827 	 *
828 	 * Note, to prevent recursion issues caused by loading and binding the
829 	 * debugging libraries themselves, a local debugging descriptor is
830 	 * initialized.  Once the debugging setup has completed, this local
831 	 * descriptor is copied to the global descriptor which effectively
832 	 * enables diagnostic output.
833 	 *
834 	 * Ignore any debugging request if we're being monitored by a process
835 	 * that expects the old getpid() initialization handshake.
836 	 */
837 	if ((rpl_debug || prm_debug) && ((rtld_flags & RT_FL_DEBUGGER) == 0)) {
838 		Dbg_desc	_dbg_desc = {0};
839 		struct timeval	total = DBG_TOTALTIME;
840 		struct timeval	delta = DBG_DELTATIME;
841 
842 		if (rpl_debug) {
843 			if (dbg_setup(rpl_debug, &_dbg_desc) == 0)
844 				return (0);
845 			if (_dbg_desc.d_extra & DBG_E_HELP_EXIT)
846 				rtldexit(&lml_main, 0);
847 		}
848 		if (prm_debug)
849 			(void) dbg_setup(prm_debug, &_dbg_desc);
850 
851 		*dbg_desc = _dbg_desc;
852 		DBG_TOTALTIME = total;
853 		DBG_DELTATIME = delta;
854 	}
855 
856 	/*
857 	 * Now that debugging is enabled generate any diagnostics from any
858 	 * previous events.
859 	 */
860 	if (DBG_ENABLED) {
861 		DBG_CALL(Dbg_cap_val(&lml_main, org_scapset, alt_scapset,
862 		    M_MACH));
863 		DBG_CALL(Dbg_file_config_dis(&lml_main, config->c_name,
864 		    features));
865 
866 		DBG_CALL(Dbg_file_ldso(rlmp, envp, auxv,
867 		    LIST(rlmp)->lm_lmidstr, ALIST_OFF_DATA));
868 
869 		if (THIS_IS_ELF(mlmp)) {
870 			DBG_CALL(Dbg_file_elf(&lml_main, PATHNAME(mlmp),
871 			    ADDR(mlmp), MSIZE(mlmp), LIST(mlmp)->lm_lmidstr,
872 			    ALIST_OFF_DATA));
873 		}
874 	}
875 
876 	/*
877 	 * Enable auditing.
878 	 */
879 	if (rpl_audit || prm_audit || profile_lib) {
880 		int		ndx;
881 		const char	*aud[3];
882 
883 		aud[0] = rpl_audit;
884 		aud[1] = prm_audit;
885 		aud[2] = profile_lib;
886 
887 		/*
888 		 * Any global auditing (set using LD_AUDIT or LD_PROFILE) that
889 		 * can't be established is non-fatal.
890 		 */
891 		if ((auditors = calloc(1, sizeof (Audit_desc))) == NULL)
892 			return (0);
893 
894 		for (ndx = 0; ndx < 3; ndx++) {
895 			if (aud[ndx]) {
896 				if ((auditors->ad_name =
897 				    strdup(aud[ndx])) == NULL)
898 					return (0);
899 				rtld_flags2 |= RT_FL2_FTL2WARN;
900 				(void) audit_setup(mlmp, auditors,
901 				    PD_FLG_EXTLOAD, NULL);
902 				rtld_flags2 &= ~RT_FL2_FTL2WARN;
903 			}
904 		}
905 		lml_main.lm_tflags |= auditors->ad_flags;
906 	}
907 	if (AUDITORS(mlmp)) {
908 		/*
909 		 * Any object required auditing (set with a DT_DEPAUDIT dynamic
910 		 * entry) that can't be established is fatal.
911 		 */
912 		if (FLAGS1(mlmp) & FL1_RT_GLOBAUD) {
913 			/*
914 			 * If this object requires global auditing, use the
915 			 * local auditing information to set the global
916 			 * auditing descriptor.  The effect is that a
917 			 * DT_DEPAUDIT act as an LD_AUDIT.
918 			 */
919 			if ((auditors == NULL) && ((auditors = calloc(1,
920 			    sizeof (Audit_desc))) == NULL))
921 				return (0);
922 
923 			auditors->ad_name = AUDITORS(mlmp)->ad_name;
924 			if (audit_setup(mlmp, auditors, 0, NULL) == 0)
925 				return (0);
926 			lml_main.lm_tflags |= auditors->ad_flags;
927 
928 			/*
929 			 * Clear the local auditor information.
930 			 */
931 			free((void *) AUDITORS(mlmp));
932 			AUDITORS(mlmp) = NULL;
933 
934 		} else {
935 			/*
936 			 * Establish any local auditing.
937 			 */
938 			if (audit_setup(mlmp, AUDITORS(mlmp), 0, NULL) == 0)
939 				return (0);
940 
941 			AFLAGS(mlmp) |= AUDITORS(mlmp)->ad_flags;
942 			lml_main.lm_flags |= LML_FLG_LOCAUDIT;
943 		}
944 	}
945 
946 	/*
947 	 * Explicitly add the initial object and ld.so.1 to those objects being
948 	 * audited.  Note, although the ld.so.1 link-map isn't auditable,
949 	 * establish a cookie for ld.so.1 as this may be bound to via the
950 	 * dl*() family.
951 	 */
952 	if ((lml_main.lm_tflags | AFLAGS(mlmp)) & LML_TFLG_AUD_MASK) {
953 		if (((audit_objopen(mlmp, mlmp) == 0) ||
954 		    (audit_objopen(mlmp, rlmp) == 0)) &&
955 		    (AFLAGS(mlmp) & LML_TFLG_AUD_MASK))
956 			return (0);
957 	}
958 
959 	/*
960 	 * Map in any preloadable shared objects.  Establish the caller as the
961 	 * head of the main link-map list.  In the case of being exercised from
962 	 * lddstub, the caller gets reassigned to the first target shared object
963 	 * so as to provide intuitive diagnostics from ldd().
964 	 *
965 	 * Note, it is valid to preload a 4.x shared object with a 5.0
966 	 * executable (or visa-versa), as this functionality is required by
967 	 * ldd(1).
968 	 */
969 	clmp = mlmp;
970 	if (rpl_preload && (preload(rpl_preload, mlmp, &clmp) == 0))
971 		return (0);
972 	if (prm_preload && (preload(prm_preload, mlmp, &clmp) == 0))
973 		return (0);
974 
975 	/*
976 	 * Load all dependent (needed) objects.
977 	 */
978 	if (analyze_lmc(&lml_main, ALIST_OFF_DATA, mlmp, mlmp, NULL) == NULL)
979 		return (0);
980 
981 	/*
982 	 * Relocate all the dependencies we've just added.
983 	 *
984 	 * If this process has been established via crle(1), the environment
985 	 * variable LD_CONFGEN will have been set.  crle(1) may create this
986 	 * process twice.  The first time crle only needs to gather dependency
987 	 * information.  The second time, is to dldump() the images.
988 	 *
989 	 * If we're only gathering dependencies, relocation is unnecessary.
990 	 * As crle(1) may be building an arbitrary family of objects, they may
991 	 * not fully relocate either.  Hence the relocation phase is not carried
992 	 * out now, but will be called by crle(1) once all objects have been
993 	 * loaded.
994 	 */
995 	if ((rtld_flags & RT_FL_CONFGEN) == 0) {
996 
997 		DBG_CALL(Dbg_util_nl(&lml_main, DBG_NL_STD));
998 
999 		if (relocate_lmc(&lml_main, ALIST_OFF_DATA, mlmp,
1000 		    mlmp, NULL) == 0)
1001 			return (0);
1002 
1003 		/*
1004 		 * Inform the debuggers that basic process initialization is
1005 		 * complete, and that the state of ld.so.1 (link-map lists,
1006 		 * etc.) is stable.  This handshake enables the debugger to
1007 		 * initialize themselves, and consequently allows the user to
1008 		 * set break points in .init code.
1009 		 *
1010 		 * Most new debuggers use librtld_db to monitor activity events.
1011 		 * Older debuggers indicated their presence by setting the
1012 		 * DT_DEBUG entry in the dynamic executable (see elf_new_lm()).
1013 		 * In this case, getpid() is called so that the debugger can
1014 		 * catch the system call.  This old mechanism has some
1015 		 * restrictions, as getpid() should not be called prior to
1016 		 * basic process initialization being completed.  This
1017 		 * restriction has become increasingly difficult to maintain,
1018 		 * as the use of auditors, LD_DEBUG, and the initialization
1019 		 * handshake with libc can result in "premature" getpid()
1020 		 * calls.  The use of this getpid() handshake is expected to
1021 		 * disappear at some point in the future, and there is intent
1022 		 * to work towards that goal.
1023 		 */
1024 		rd_event(&lml_main, RD_DLACTIVITY, RT_CONSISTENT);
1025 		rd_event(&lml_rtld, RD_DLACTIVITY, RT_CONSISTENT);
1026 
1027 		if (rtld_flags & RT_FL_DEBUGGER) {
1028 			r_debug.rtd_rdebug.r_flags |= RD_FL_ODBG;
1029 			(void) getpid();
1030 		}
1031 	}
1032 
1033 	/*
1034 	 * Indicate preinit activity, and call any auditing routines.  These
1035 	 * routines are called before initializing any threads via libc, or
1036 	 * before collecting the complete set of .inits on the primary link-map.
1037 	 * Although most libc interfaces are encapsulated in local routines
1038 	 * within libc, they have been known to escape (ie. call a .plt).  As
1039 	 * the appcert auditor uses preinit as a trigger to establish some
1040 	 * external interfaces to the main link-maps libc, we need to activate
1041 	 * this trigger before exercising any code within libc.  Additionally,
1042 	 * I wouldn't put it past an auditor to add additional objects to the
1043 	 * primary link-map.  Hence, we collect .inits after the audit call.
1044 	 */
1045 	rd_event(&lml_main, RD_PREINIT, 0);
1046 
1047 	if (aud_activity ||
1048 	    ((lml_main.lm_tflags | AFLAGS(mlmp)) & LML_TFLG_AUD_ACTIVITY))
1049 		audit_activity(mlmp, LA_ACT_CONSISTENT);
1050 	if (aud_preinit ||
1051 	    ((lml_main.lm_tflags | AFLAGS(mlmp)) & LML_TFLG_AUD_PREINIT))
1052 		audit_preinit(mlmp);
1053 
1054 	/*
1055 	 * If we're creating initial configuration information, we're done
1056 	 * now that the auditing step has been called.
1057 	 */
1058 	if (rtld_flags & RT_FL_CONFGEN) {
1059 		leave(LIST(mlmp), 0);
1060 		return (mlmp);
1061 	}
1062 
1063 	/*
1064 	 * Sort the .init sections of all objects we've added.  If we're
1065 	 * tracing we only need to execute this under ldd(1) with the -i or -u
1066 	 * options.
1067 	 */
1068 	lmflags = lml_main.lm_flags;
1069 	if (((lmflags & LML_FLG_TRC_ENABLE) == 0) ||
1070 	    (lmflags & (LML_FLG_TRC_INIT | LML_FLG_TRC_UNREF))) {
1071 		if ((tobj = tsort(mlmp, LIST(mlmp)->lm_init,
1072 		    RT_SORT_REV)) == (Rt_map **)S_ERROR)
1073 			return (0);
1074 	}
1075 
1076 	/*
1077 	 * If we are tracing we're done.  This is the one legitimate use of a
1078 	 * direct call to rtldexit() rather than return, as we don't want to
1079 	 * return and jump to the application.
1080 	 */
1081 	if (lmflags & LML_FLG_TRC_ENABLE) {
1082 		unused(&lml_main);
1083 		rtldexit(&lml_main, 0);
1084 	}
1085 
1086 	/*
1087 	 * Check if this instance of the linker should have a primary link
1088 	 * map.  This flag allows multiple copies of the -same- -version-
1089 	 * of the linker (and libc) to run in the same address space.
1090 	 *
1091 	 * Without this flag we only support one copy of the linker in a
1092 	 * process because by default the linker will always try to
1093 	 * initialize at one primary link map  The copy of libc which is
1094 	 * initialized on a primary link map will initialize global TLS
1095 	 * data which can be shared with other copies of libc in the
1096 	 * process.  The problem is that if there is more than one copy
1097 	 * of the linker, only one copy should link libc onto a primary
1098 	 * link map, otherwise libc will attempt to re-initialize global
1099 	 * TLS data.  So when a copy of the linker is loaded with this
1100 	 * flag set, it will not initialize any primary link maps since
1101 	 * presumably another copy of the linker will do this.
1102 	 *
1103 	 * Note that this flag only allows multiple copies of the -same-
1104 	 * -version- of the linker (and libc) to coexist.  This approach
1105 	 * will not work if we are trying to load different versions of
1106 	 * the linker and libc into the same process.  The reason for
1107 	 * this is that the format of the global TLS data may not be
1108 	 * the same for different versions of libc.  In this case each
1109 	 * different version of libc must have it's own primary link map
1110 	 * and be able to maintain it's own TLS data.  The only way this
1111 	 * can be done is by carefully managing TLS pointers on transitions
1112 	 * between code associated with each of the different linkers.
1113 	 * Note that this is actually what is done for processes in lx
1114 	 * branded zones.  Although in the lx branded zone case, the
1115 	 * other linker and libc are actually gld and glibc.  But the
1116 	 * same general TLS management mechanism used by the lx brand
1117 	 * would apply to any attempts to run multiple versions of the
1118 	 * solaris linker and libc in a single process.
1119 	 */
1120 	if (auxflags & AF_SUN_NOPLM)
1121 		rtld_flags2 |= RT_FL2_NOPLM;
1122 
1123 	/*
1124 	 * Establish any static TLS for this primary link-map.  Note, regardless
1125 	 * of whether TLS is available, an initial handshake occurs with libc to
1126 	 * indicate we're processing the primary link-map.  Having identified
1127 	 * the primary link-map, initialize threads.
1128 	 */
1129 	if (rt_get_extern(&lml_main, mlmp) == 0)
1130 		return (0);
1131 
1132 	if ((rtld_flags2 & RT_FL2_NOPLM) == 0) {
1133 		if (tls_statmod(&lml_main, mlmp) == 0)
1134 			return (0);
1135 		rt_thr_init(&lml_main);
1136 		rtld_flags2 |= RT_FL2_PLMSETUP;
1137 	} else {
1138 		rt_thr_init(&lml_main);
1139 	}
1140 
1141 	/*
1142 	 * Fire all dependencies .init sections.  Identify any unused
1143 	 * dependencies, and leave the runtime linker - effectively calling
1144 	 * the dynamic executables entry point.
1145 	 */
1146 	call_array(PREINITARRAY(mlmp), (uint_t)PREINITARRAYSZ(mlmp), mlmp,
1147 	    SHT_PREINIT_ARRAY);
1148 
1149 	if (tobj)
1150 		call_init(tobj, DBG_INIT_SORT);
1151 
1152 	rd_event(&lml_main, RD_POSTINIT, 0);
1153 
1154 	unused(&lml_main);
1155 
1156 	DBG_CALL(Dbg_util_call_main(mlmp));
1157 
1158 	rtld_flags |= (RT_FL_OPERATION | RT_FL_APPLIC);
1159 
1160 	leave(LIST(mlmp), 0);
1161 
1162 	return (mlmp);
1163 }
1164