xref: /titanic_41/usr/src/cmd/sgs/include/rtld.h (revision 0bb073995ac5a95bd35f2dd790df1ea3d8c2d507)
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 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef	_RTLD_H
28 #define	_RTLD_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*
33  * Global include file for the runtime linker.
34  */
35 #include <time.h>
36 #include <sgs.h>
37 #include <thread.h>
38 #include <synch.h>
39 #include <link.h>
40 #include <sys/avl.h>
41 #include <alist.h>
42 #include <libc_int.h>
43 
44 #ifdef	_SYSCALL32
45 #include <inttypes.h>
46 #endif
47 
48 #ifdef	__cplusplus
49 extern "C" {
50 #endif
51 
52 
53 /*
54  * Linked list of directories or filenames (built from colon separated string).
55  */
56 typedef struct pnode {
57 	const char	*p_name;
58 	const char	*p_oname;
59 	size_t		p_len;
60 	uint_t		p_orig;
61 	void		*p_info;
62 	struct pnode	*p_next;
63 } Pnode;
64 
65 typedef struct rt_map	Rt_map;
66 
67 /*
68  * A binding descriptor.  Establishes the binding relationship between two
69  * objects, the caller (originator) and the dependency (destination).
70  */
71 typedef struct {
72 	Rt_map		*b_caller;	/* caller (originator) of a binding */
73 	Rt_map		*b_depend;	/* dependency (destination) of a */
74 					/*	binding */
75 	uint_t		b_flags;	/* relationship of caller to the */
76 					/*	dependency */
77 } Bnd_desc;
78 
79 #define	BND_NEEDED	0x0001		/* caller NEEDED the dependency */
80 #define	BND_REFER	0x0002		/* caller relocation references the */
81 					/*	dependency */
82 #define	BND_FILTER	0x0004		/* pseudo binding to identify filter */
83 
84 /*
85  * Private structure for communication between rtld_db and rtld.
86  *
87  * We must bump the version number when ever an update in one of the
88  * structures/fields that rtld_db reads is updated.  This hopefully permits
89  * rtld_db implementations of the future to recognize core files produced on
90  * older systems and deal with these core files accordingly.
91  *
92  * As of version 'RTLD_DB_VERSION <= 2' the following fields were valid for core
93  * file examination (basically the public Link_map):
94  *
95  *		ADDR()
96  *		NAME()
97  *		DYN()
98  *		NEXT()
99  *		PREV()
100  *
101  * Valid fields for RTLD_DB_VERSION3
102  *
103  *		PATHNAME()
104  *		PADSTART()
105  *		PADIMLEN()
106  *		MSIZE()
107  *		FLAGS()
108  *		FLAGS1()
109  *
110  * Valid fields for RTLD_DB_VERSION4
111  *
112  *		TLSMODID()
113  *
114  * Valid fields for RTLD_DB_VERSION5
115  *
116  *		Added rtld_flags & FLG_RT_RELOCED to stable flags range
117  *
118  */
119 #define	R_RTLDDB_VERSION1	1	/* base version level - used for core */
120 					/*	file examination */
121 #define	R_RTLDDB_VERSION2	2	/* minor revision - not relevant for */
122 					/*	core files */
123 #define	R_RTLDDB_VERSION3	3
124 #define	R_RTLDDB_VERSION4	4
125 #define	R_RTLDDB_VERSION5	5
126 #define	R_RTLDDB_VERSION	R_RTLDDB_VERSION5	/* current version */
127 
128 typedef struct rtld_db_priv {
129 	struct r_debug	rtd_rdebug;	/* original r_debug structure */
130 	Word		rtd_version;	/* version no. */
131 	size_t		rtd_objpad;	/* padding around mmap()ed objects */
132 	List *		rtd_dynlmlst;	/* pointer to Dynlm_list */
133 } Rtld_db_priv;
134 
135 #ifdef _SYSCALL32
136 typedef struct rtld_db_priv32 {
137 	struct r_debug32 rtd_rdebug;	/* original r_debug structure */
138 	Elf32_Word	rtd_version;	/* version no. */
139 	Elf32_Word	rtd_objpad;	/* padding around mmap()ed objects */
140 	Elf32_Addr	rtd_dynlmlst;	/* pointer to Dynlm_list */
141 } Rtld_db_priv32;
142 #endif	/* _SYSCALL32 */
143 
144 /*
145  * External function definitions.  ld.so.1 must convey information to libc in
146  * regards to threading.  libc also provides routines for atexit() and message
147  * localization.  libc provides the necessary interfaces via its RTLDINFO
148  * structure and/or later _ld_libc() calls.
149  *
150  * These external functions are maintained for each link-map list, and used
151  * where appropriate.  The functions are associated with the object that
152  * provided them, so that should the object be deleted (say, from an alternative
153  * link-map), the functions can be removed.
154  */
155 typedef struct {
156 	Rt_map	*lc_lmp;			/* function provider */
157 	union {
158 		int		(*lc_func)();	/* external function pointer */
159 		uintptr_t	lc_val;		/* external value */
160 		char    	*lc_ptr;	/* external character pointer */
161 	} lc_un;
162 } Lc_desc;
163 
164 /*
165  * Link map list definition.  Link-maps are used to describe each loaded object.
166  * Lists of these link-maps describe the various namespaces within a process.
167  * The process executable and its dependencies are maintained on the lml_main
168  * list.  The runtime linker, and its dependencies are maintained on the
169  * lml_rtld list.  Additional lists can be created (see dlmopen()) for such
170  * things as auditors and their dependencies.
171  *
172  * Each link-map list maintains an Alist of one, or more, linked lists of
173  * link-maps.  For backward compatibility, the lm_head/lm_tail elements are
174  * initialized to the first linked-list of link-maps:
175  *
176  *      Lm_list
177  *    ----------
178  *   | lm_tail  | ------------------------------------
179  *   | lm_head  | --------------------                |
180  *   |          |                     |     Rt_map    |     Rt_map
181  *   |          |                     |     ------    |     ------
182  *   |          |          Alist       --> |      |   |--> |      |
183  *   |          |        ---------    |    |      | --     |      |
184  *   | lm_lists | ----> |         |   |    |      |    --> |      |
185  *   |          |       |---------|   |    |      |   |    |      |
186  *   |          |       | lc_head | --      ------    |     ------
187  *   |          |       | lc_tail | ------------------
188  *   |          |       |---------|
189  *                      | lc_head |
190  *                      | lc_tail |
191  *                      |---------|
192  *
193  * Multiple link-map lists exist to support the addition of lazy loaded
194  * families, filtee families, and dlopen() families.  The intent of these
195  * lists is to insure that a family of objects that are to be loaded are
196  * fully relocatable, and hence usable, before they become part of the main
197  * (al_data[0]) link-map control list.  This main link-map control list is
198  * the only list in existence when control is transferred to user code.
199  *
200  * During process initialization, the dynamic executable and its non-lazy
201  * dependencies are maintained on al_data[0].  If a new object is loaded, then
202  * this object is added to the next available control list [1], typically
203  * al_data[1].  Any dependencies of this object that have not already been
204  * loaded are added to the same control list.  Once all of the objects on the
205  * new control list have been successfully relocated, the objects are moved from
206  * the new control list to the highest control list to which objects of the new
207  * control list bound to, typically al_data[1] to al_data[0].
208  *
209  * Each loading scenario can be broken down as follows:
210  *
211  *  setup() - only the initial link-map control list is used:
212  *   i.	  create al_data[0]
213  *   ii.  add new link-map for main on al_data[0]
214  *   iii. analyze al_data[0] to add all non-lazy dependencies
215  *   iv.  relocate al_data[0] dependencies.
216  *
217  *  dlopen() - the initiator can only be the initial link-map control list:
218  *   i.   create al_data[1] from caller al_data[0]
219  *   ii.  add new link-map for the dlopen'ed object on al_data[1]
220  *   iii. analyze al_data[1] to add all non-lazy dependencies
221  *   iv.  relocate al_data[1] dependencies, and move to al_data[0].
222  *
223  *  filtee and lazy loading processing - the initiator can be any link-map
224  *  control list that is being relocated:
225  *   i.   create al_data[y] from caller al_data[x]
226  *   ii.  add new link-map for the new object on al_data[y]
227  *   iii. analyze al_data[y] to add all non-lazy dependencies
228  *   iv.  relocate al_data[y] dependencies, and move to al_data[x].
229  *
230  * This Alist therefore maintains a stack of link-map control lists.  The newest
231  * link-map control list can locate symbols within any of the former lists,
232  * however, control is not passed to a former list until the newest lists
233  * processing is complete.  Thus, objects can't bind to new objects until they
234  * have been fully analyzed and relocated.
235  *
236  * [1]  Note, additional link-map control list creation occurs after the head
237  * link-map object (typically the dynamic executable) has been relocated.  This
238  * staging is required to satisfy the binding requirements of copy relocations.
239  * Copy relocations, effectively, transfer the bindings of the copied data
240  * (say _iob in libc.so.1) to the copy location (_iob in the application).
241  * Thus an object that might bind to the original copy data must be redirected
242  * to the copy reference.  As the knowledge of a copy relocation having taken
243  * place is only known after relocating the application, link-map control list
244  * additions are suspended until after this relocation has completed.
245  */
246 typedef struct {
247 	Rt_map		*lc_head;
248 	Rt_map		*lc_tail;
249 	APlist		*lc_now;	/* pending promoted bind-now objects */
250 	uint_t		lc_flags;
251 } Lm_cntl;
252 
253 #define	LMC_FLG_ANALYZING	0x01	/* control list is being analyzed */
254 #define	LMC_FLG_RELOCATING	0x02	/* control list is being relocated */
255 #define	LMC_FLG_REANALYZE	0x04	/* repeat analysis (established when */
256 					/*	interposers are added */
257 
258 struct lm_list {
259 	/*
260 	 * BEGIN: Exposed to rtld_db - don't move, don't delete
261 	 */
262 	Rt_map		*lm_head;	/* linked list pointers to active */
263 	Rt_map		*lm_tail;	/*	link-map list */
264 	APlist		*lm_handle;	/* not used by rtld_db - but spacing */
265 					/*	is required for flags */
266 	Word		lm_flags;
267 	/*
268 	 * END: Exposed to rtld_db - don't move, don't delete
269 	 */
270 	Alist		*lm_rti;	/* list of RTLDINFO tables */
271 	Audit_list	*lm_alp;	/* audit list descriptor */
272 	avl_tree_t	*lm_fpavl;	/* avl tree of objects loaded */
273 	Alist		*lm_lists;	/* active and pending link-map lists */
274 	char		***lm_environ;	/* pointer to environment array */
275 	Word		lm_tflags;	/* transferable flags */
276 	uint_t		lm_obj;		/* total number of objs on link-map */
277 	uint_t		lm_init;	/* new obj since last init processing */
278 	uint_t		lm_lazy;	/* obj with pending lazy dependencies */
279 	uint_t		lm_tls;		/* new obj that require TLS */
280 	uint_t		lm_lmid;	/* unique link-map list identifier, */
281 	char		*lm_lmidstr;	/* and associated diagnostic string */
282 	APlist		*lm_actaudit;	/* list of pending audit activity */
283 	Lc_desc		lm_lcs[CI_MAX];	/* external libc functions */
284 };
285 
286 #ifdef	_SYSCALL32
287 struct lm_list32 {
288 	/*
289 	 * BEGIN: Exposed to rtld_db - don't move, don't delete
290 	 */
291 	Elf32_Addr	lm_head;
292 	Elf32_Addr	lm_tail;
293 	Elf32_Addr	lm_handle;
294 	Elf32_Word	lm_flags;
295 	/*
296 	 * END: Exposed to rtld_db - don't move, don't delete
297 	 */
298 	Elf32_Addr	lm_rti;
299 	Elf32_Addr	lm_fpavl;
300 	Elf32_Addr	lm_lists;
301 	Elf32_Addr	lm_environ;
302 	Elf32_Word	lm_tflags;
303 	uint_t		lm_obj;
304 	uint_t		lm_init;
305 	uint_t		lm_lazy;
306 	uint_t		lm_tls;
307 	uint_t		lm_lmid;
308 	Elf32_Addr	lm_lmidstr;
309 	Elf32_Addr	lm_actaudit;
310 	Elf32_Addr	lm_lcs[CI_MAX];
311 };
312 #endif /* _SYSCALL32 */
313 
314 /*
315  * Possible Link_map list flags (Lm_list.lm_flags)
316  */
317 /*
318  * BEGIN: Exposed to rtld_db - don't move, don't delete
319  */
320 #define	LML_FLG_BASELM		0x00000001	/* primary link-map */
321 #define	LML_FLG_RTLDLM		0x00000002	/* rtld link-map */
322 /*
323  * END: Exposed to rtld_db - don't move, don't delete
324  */
325 #define	LML_FLG_NOAUDIT		0x00000004	/* symbol auditing disabled */
326 #define	LML_FLG_PLTREL		0x00000008	/* deferred plt relocation */
327 						/* 	initialization */
328 						/*	(ld.so.1 only) */
329 #define	LML_FLG_HOLDLOCK	0x00000010	/* hold the rtld mutex lock */
330 #define	LML_FLG_ENVIRON		0x00000020	/* environ var initialized */
331 #define	LML_FLG_INTRPOSE	0x00000040	/* interposing objs on list */
332 #define	LML_FLG_LOCAUDIT	0x00000080	/* local auditors exists for */
333 						/*	this link-map list */
334 #define	LML_FLG_LOADAVAIL	0x00000100	/* load anything available */
335 #define	LML_FLG_IGNRELERR	0x00000200	/* ignore relocation errors - */
336 						/*	internal for crle(1) */
337 #define	LML_FLG_DBNOTIF		0x00000400	/* binding activity going on */
338 #define	LML_FLG_STARTREL	0x00000800	/* relocation started */
339 #define	LML_FLG_ATEXIT		0x00001000	/* atexit processing */
340 #define	LML_FLG_OBJADDED	0x00002000	/* object(s) added */
341 #define	LML_FLG_OBJDELETED	0x00004000	/* object(s) deleted */
342 #define	LML_FLG_OBJREEVAL	0x00008000	/* existing object(s) needs */
343 						/*	tsort reevaluation */
344 #define	LML_FLG_NOPENDGLBLAZY	0x00010000	/* no pending, global, lazy */
345 						/*	dependencies remain */
346 #define	LML_FLG_INTRPOSETSORT	0x00020000	/* interpose tsorting done */
347 #define	LML_FLG_AUDITNOTIFY	0x00040000	/* audit consistent required */
348 #define	LML_FLG_GROUPSEXIST	0x00080000	/* local groups exist */
349 
350 #define	LML_FLG_TRC_LDDSTUB	0x00100000	/* identify lddstub */
351 #define	LML_FLG_TRC_ENABLE	0x00200000	/* tracing enabled (ldd) */
352 #define	LML_FLG_TRC_WARN	0x00400000	/* print warnings for undefs */
353 #define	LML_FLG_TRC_VERBOSE	0x00800000	/* verbose (versioning) trace */
354 #define	LML_FLG_TRC_SEARCH	0x01000000	/* trace search paths */
355 #define	LML_FLG_TRC_UNREF	0x02000000	/* trace unreferenced */
356 						/*	dependencies */
357 #define	LML_FLG_TRC_UNUSED	0x04000000	/* trace unused dependencies */
358 #define	LML_FLG_TRC_INIT	0x08000000	/* print .init order */
359 #define	LML_FLG_TRC_NOUNRESWEAK	0x10000000	/* unresolved weak references */
360 						/*	are not allowed */
361 #define	LML_FLG_TRC_NOPAREXT	0x20000000	/* unresolved PARENT/EXTERN */
362 						/*	references are not */
363 						/*	allowed */
364 #define	LML_MSK_TRC		0xfff00000	/* tracing mask */
365 
366 /*
367  * Possible Link_map transferable flags (Lm_list.lm_tflags), i.e., link-map
368  * list flags that can be propagated to any new link-map list created.
369  */
370 #define	LML_TFLG_NOLAZYLD	0x00000001	/* lazy loading disabled */
371 #define	LML_TFLG_NODIRECT	0x00000002	/* direct bindings disabled */
372 
373 #define	LML_TFLG_LOADFLTR	0x00000008	/* trigger filtee loading */
374 
375 #define	LML_TFLG_AUD_PREINIT	0x00100000	/* preinit (audit) exists */
376 #define	LML_TFLG_AUD_OBJSEARCH	0x00200000	/* objsearch (audit) exists */
377 #define	LML_TFLG_AUD_OBJOPEN	0x00400000	/* objopen (audit) exists */
378 #define	LML_TFLG_AUD_OBJFILTER	0x00800000	/* objfilter (audit) exists */
379 #define	LML_TFLG_AUD_OBJCLOSE	0x01000000	/* objclose (audit) exists */
380 #define	LML_TFLG_AUD_SYMBIND	0x02000000	/* symbind (audit) exists */
381 #define	LML_TFLG_AUD_PLTENTER	0x04000000	/* pltenter (audit) exists */
382 #define	LML_TFLG_AUD_PLTEXIT	0x08000000	/* pltexit (audit) exists */
383 #define	LML_TFLG_AUD_ACTIVITY	0x10000000	/* activity (audit) exists */
384 
385 /*
386  * NOTE: Audit flags have duplicated FLAGS1() values.  If more audit flags are
387  * added, update the FLAGS1() reservation FL1_AUD_RS_STR to FL1_AUD_RS_END
388  * defined later.
389  */
390 #define	LML_TFLG_AUD_MASK	0xfff00000	/* audit interfaces mask */
391 
392 /*
393  * Define a Group Handle.
394  *
395  * The capability of ld.so.1 to associate a group of objects, look for symbols
396  * within that group, ensure that groups are isolated from one another (with
397  * regard to relocations), and to unload a group, centers around a handle.  This
398  * data structure is tracked from the link-map HANDLE(), and is the structure
399  * returned from dlopen(), and similar object loading capabilities such as
400  * filter/filtee processing.
401  *
402  * A handle keeps track of all the dependencies of the associated object.
403  * These dependencies may be added as objects are lazily loaded.  The core
404  * dependencies on the handle are the ldd(1) list of the associated object.
405  * The object assigned the handle, and the parent (or caller) who requested the
406  * handle are also maintained as dependencies on the handle.
407  *
408  * Presently, an object may have two handles, one requested with RTLD_FIRST
409  * and one without.
410  *
411  * A handle may be referenced by any number of parents (callers).  A reference
412  * count tracks the number.  A dlclose() operation drops the reference count,
413  * and when the count is zero, the handle is used to determine the family of
414  * objects to unload.  As bindings may occur to objects on the handle from
415  * other handles, it may not be possible to remove a complete family of
416  * objects or that handle itself.  Handles in this state are moved to an orphan
417  * list.  A handle on the orphan list is taken off the orphan list if the
418  * associated object is reopened.  Otherwise, the handle remains on the orphan
419  * list for the duration of the process.  The orphan list is inspected any time
420  * objects are unloaded, to determine if the orphaned objects can also be
421  * unloaded.
422  *
423  * Objects can be dlopened using RTLD_NOW.  This attribute requires that all
424  * relocations of the object, and its dependencies are processed immediately,
425  * before return to the caller.  Typically, an object is loaded without
426  * RTLD_NOW, and procedure linkage relocations are satisfied when their
427  * associated function is first called.  If an object is already loaded, and an
428  * RTLD_NOW request is made, then the object, and its dependencies, most undergo
429  * additional relocation processing.   This promotion from lazy binding to
430  * immediate binding is carried out using handles, as the handle defines the
431  * dependencies that must be processed.  A temporary handle is created for this
432  * purpose, and is discarded immediately after the promotion operation has been
433  * completed.
434  */
435 typedef struct {
436 	Alist		*gh_depends;	/* handle dependency list */
437 	Rt_map		*gh_ownlmp;	/* handle owners link-map */
438 	Lm_list		*gh_ownlml;	/* handle owners link-map list */
439 	uint_t		gh_refcnt;	/* handle reference count */
440 	uint_t		gh_flags;	/* handle flags (GPH_ values) */
441 } Grp_hdl;
442 
443 #define	GPH_ZERO	0x0001		/* special handle for dlopen(0) */
444 #define	GPH_LDSO	0x0002		/* special handle for ld.so.1 */
445 #define	GPH_FIRST	0x0004		/* dlsym() can only use originating */
446 					/*	dependency */
447 #define	GPH_FILTEE	0x0008		/* handle used to specify a filtee */
448 #define	GPH_INITIAL	0x0010		/* handle is initialized */
449 #define	GPH_NOPENDLAZY	0x0020		/* no pending lazy dependencies */
450 					/*	remain for this handle */
451 
452 /*
453  * Define a Group Descriptor.
454  *
455  * Each dependency associated with a group handle is maintained by a group
456  * descriptor.  The descriptor defines the associated dependency together with
457  * flags that indicate how the dependency can be used.
458  */
459 typedef struct {
460 	Rt_map *	gd_depend;	/* dependency */
461 	uint_t		gd_flags;	/* dependency flags (GPD_ values) */
462 } Grp_desc;
463 
464 #define	GPD_DLSYM	0x0001		/* dependency available to dlsym() */
465 #define	GPD_RELOC	0x0002		/* dependency available to satisfy */
466 					/*	relocation binding */
467 #define	GPD_ADDEPS	0x0004		/* dependencies of this dependency */
468 					/*	should be added to handle */
469 #define	GPD_PARENT	0x0008		/* dependency is a parent */
470 #define	GPD_FILTER	0x0010		/* dependency is our filter */
471 #define	GPD_PROMOTE	0x0020		/* dependency is our RTLD_NOW */
472 					/*	promoter */
473 #define	GPD_REMOVE	0x1000		/* descriptor is a candidate for */
474 					/*	removal from the group */
475 
476 /*
477  * Define threading structures.  For compatibility with libthread (T1_VERSION 1
478  * and TI_VERSION 2) our locking structure is sufficient to hold a mutex or a
479  * readers/writers lock.
480  */
481 typedef struct {
482 	union {
483 		mutex_t		l_mutex;
484 		rwlock_t	l_rwlock;
485 	} u;
486 } Rt_lock;
487 
488 typedef	cond_t	Rt_cond;
489 
490 /*
491  * Define a dynamic section information descriptor.  This parallels the entries
492  * in the .dynamic section and holds auxiliary information to implement lazy
493  * loading and filtee processing.
494  */
495 typedef struct {
496 	uint_t	di_flags;
497 	void	*di_info;
498 } Dyninfo;
499 
500 #define	FLG_DI_STDFLTR	0x00001		/* .dynamic entry for DT_FILTER */
501 #define	FLG_DI_AUXFLTR	0x00002		/* .dynamic entry for DT_AUXILIARY */
502 #define	FLG_DI_SYMFLTR	0x00004		/* .dynamic entry for DT_SYMFILTER */
503 					/*	and DT_SYMAUXILIARY */
504 #define	MSK_DI_FILTER	0x0000f		/* mask for all filter possibilities */
505 
506 #define	FLG_DI_POSFLAG1	0x00010		/* .dynamic entry for DT_POSFLAG_1 */
507 #define	FLG_DI_NEEDED	0x00020		/* .dynamic entry for DT_NEEDED */
508 #define	FLG_DI_LAZY	0x00100		/* lazy needed entry - preceded by */
509 					/*    DF_P1_LAZYLOAD (DT_POSFLAG_1) */
510 #define	FLG_DI_GROUP	0x00200		/* group needed entry - preceded by */
511 					/*    DF_P1_GROUPPERM (DT_POSFLAG_1) */
512 
513 #define	FLG_DI_LDD_DONE	0x01000		/* entry has been processed (ldd) */
514 #define	FLG_DI_LAZYFAIL	0x02000		/* the lazy loading of this entry */
515 					/*    failed */
516 /*
517  * Data structure to track AVL tree of pathnames.  This structure provides the
518  * basis of both the "not-found" node tree, and the "full-path" node tree.  Both
519  * of these trees persist for the life of a process, although the "not-found"
520  * tree may be moved aside during a dlopen() or dlsym() fall back operation.
521  */
522 typedef struct {
523 	const char	*pn_name;	/* path name */
524 	avl_node_t	pn_avl;		/* avl book-keeping (see SGSOFFSETOF) */
525 	uint_t		pn_hash;	/* path name hash value */
526 } PathNode;
527 
528 /*
529  * Data structure to track AVL tree for full path names of objects that are
530  * loaded into memory.
531  */
532 typedef struct {
533 	PathNode	fpn_node;	/* path node */
534 	Rt_map		*fpn_lmp;	/* object link-map */
535 } FullPathNode;
536 
537 /*
538  * Define a mapping structure, which is maintained to describe each mapping
539  * of an object, ie. the text segment, data segment, bss segment, etc.
540  */
541 typedef struct {
542 	caddr_t		m_vaddr;	/* mapping address */
543 	size_t		m_fsize;	/* backing file size */
544 	size_t		m_msize;	/* mapping size */
545 	int		m_perm;		/* mapping permissions */
546 } Mmap;
547 
548 /*
549  * A given link-map can hold either a supplier or receiver copy
550  * relocation list, but not both. This union is used to overlap
551  * the space used for the two lists.
552  */
553 typedef union {
554 	Alist	*rtc_r;		/* receiver list (Rel_copy) */
555 	APlist	*rtc_s;		/* supplier list (Rt_map *) */
556 } Rt_map_copy;
557 
558 
559 /*
560  * Link-map definition.
561  */
562 struct rt_map {
563 	/*
564 	 * BEGIN: Exposed to rtld_db - don't move, don't delete
565 	 */
566 	Link_map	rt_public;	/* public data */
567 	char		*rt_pathname;	/* full pathname of loaded object */
568 	ulong_t		rt_padstart;	/* start of image (including padding) */
569 	ulong_t		rt_padimlen;	/* size of image (including padding */
570 	ulong_t		rt_msize;	/* total memory mapped */
571 	uint_t		rt_flags;	/* state flags, see FLG below */
572 	uint_t		rt_flags1;	/* state flags1, see FL1 below */
573 	ulong_t		rt_tlsmodid;	/* TLS module id */
574 	/*
575 	 * END: Exposed to rtld_db - don't move, don't delete
576 	 */
577 	APlist		*rt_alias;	/* list of linked file names */
578 	APlist		*rt_fpnode;	/* list of FullpathNode AVL nodes */
579 	void		(*rt_init)();	/* address of _init */
580 	void		(*rt_fini)();	/* address of _fini */
581 	char		*rt_runpath;	/* LD_RUN_PATH and its equivalent */
582 	Pnode		*rt_runlist;	/*	Pnode structures */
583 	APlist		*rt_depends;	/* list of dependencies */
584 	APlist		*rt_callers;	/* list of callers */
585 	APlist		*rt_handles;	/* dlopen handles */
586 	APlist		*rt_groups;	/* groups we're a member of */
587 	ulong_t		rt_etext;	/* etext address */
588 	struct fct	*rt_fct;	/* file class table for this object */
589 	Sym		*(*rt_symintp)(); /* link map symbol interpreter */
590 	void		*rt_priv;	/* private data, object type specific */
591 	Lm_list		*rt_list;	/* link map list we belong to */
592 	uint_t		rt_objfltrndx;	/* object filtees .dynamic index */
593 	uint_t		rt_symsfltrcnt;	/* number of standard symbol filtees */
594 	uint_t		rt_symafltrcnt;	/* number of auxiliary symbol filtees */
595 	int		rt_mode;	/* usage mode, see RTLD mode flags */
596 	int		rt_sortval;	/* temporary buffer to traverse graph */
597 	uint_t		rt_cycgroup;	/* cyclic group */
598 	dev_t		rt_stdev;	/* device id and inode number for .so */
599 	ino_t		rt_stino;	/*	multiple inclusion checks */
600 	char		*rt_origname;	/* original pathname of loaded object */
601 	size_t		rt_dirsz;	/*	and its size */
602 	Rt_map_copy	rt_copy;	/* list of copy relocations */
603 	Audit_desc	*rt_auditors;	/* audit descriptor array */
604 	Audit_info	*rt_audinfo;	/* audit information descriptor */
605 	Syminfo		*rt_syminfo;	/* elf .syminfo section - here */
606 					/*	because it is checked in */
607 					/*	common code */
608 	Addr		*rt_initarray;	/* .initarray table */
609 	Addr		*rt_finiarray;	/* .finiarray table */
610 	Addr		*rt_preinitarray; /* .preinitarray table */
611 	Mmap		*rt_mmaps;	/* array of mapping information */
612 	uint_t		rt_mmapcnt;	/*	and associated number */
613 	uint_t		rt_initarraysz;	/* size of .initarray table */
614 	uint_t		rt_finiarraysz;	/* size of .finiarray table */
615 	uint_t		rt_preinitarraysz; /* size of .preinitarray table */
616 	Dyninfo		*rt_dyninfo;	/* .dynamic information descriptors */
617 	uint_t		rt_dyninfocnt;	/* count of dyninfo entries */
618 	uint_t		rt_relacount;	/* no. of RELATIVE relocations */
619 	uint_t		rt_idx;		/* hold index within linkmap list */
620 	uint_t		rt_lazy;	/* lazy dependencies pending */
621 	Rt_cond		*rt_condvar;	/*	variables */
622 	Xword		rt_hwcap;	/* hardware capabilities */
623 	Xword		rt_sfcap;	/* software capabilities */
624 	thread_t	rt_threadid;	/* thread init/fini synchronization */
625 	uint_t		rt_cntl;	/* link-map control list we belong to */
626 	uint_t		rt_flags2;	/* state flags2, see FL2 below */
627 };
628 
629 
630 #ifdef _SYSCALL32
631 /*
632  * Structure to allow 64-bit rtld_db to read 32-bit processes out of procfs.
633  */
634 typedef union {
635 	uint32_t	rtc_r;
636 	uint32_t	rtc_s;
637 } Rt_map_copy32;
638 
639 typedef struct rt_map32 {
640 	/*
641 	 * BEGIN: Exposed to rtld_db - don't move, don't delete
642 	 */
643 	Link_map32	rt_public;
644 	uint32_t	rt_pathname;
645 	uint32_t	rt_padstart;
646 	uint32_t	rt_padimlen;
647 	uint32_t	rt_msize;
648 	uint32_t	rt_flags;
649 	uint32_t	rt_flags1;
650 	uint32_t	rt_tlsmodid;
651 	/*
652 	 * END: Exposed to rtld_db - don't move, don't delete
653 	 */
654 	uint32_t	rt_alias;
655 	uint32_t	rt_fpnode;
656 	uint32_t 	rt_init;
657 	uint32_t	rt_fini;
658 	uint32_t	rt_runpath;
659 	uint32_t	rt_runlist;
660 	uint32_t	rt_depends;
661 	uint32_t	rt_callers;
662 	uint32_t	rt_handles;
663 	uint32_t	rt_groups;
664 	uint32_t	rt_etext;
665 	uint32_t	rt_fct;
666 	uint32_t	rt_symintp;
667 	uint32_t	rt_priv;
668 	uint32_t 	rt_list;
669 	uint32_t 	rt_objfltrndx;
670 	uint32_t 	rt_symsfltrcnt;
671 	uint32_t 	rt_symafltrcnt;
672 	int32_t		rt_mode;
673 	int32_t		rt_sortval;
674 	uint32_t	rt_cycgroup;
675 	uint32_t	rt_stdev;
676 	uint32_t	rt_stino;
677 	uint32_t	rt_origname;
678 	uint32_t	rt_dirsz;
679 	Rt_map_copy32	rt_copy;
680 	uint32_t 	rt_auditors;
681 	uint32_t 	rt_audinfo;
682 	uint32_t	rt_syminfo;
683 	uint32_t	rt_initarray;
684 	uint32_t	rt_finiarray;
685 	uint32_t	rt_preinitarray;
686 	uint32_t	rt_mmaps;
687 	uint32_t	rt_mmapcnt;
688 	uint32_t	rt_initarraysz;
689 	uint32_t	rt_finiarraysz;
690 	uint32_t	rt_preinitarraysz;
691 	uint32_t 	rt_dyninfo;
692 	uint32_t 	rt_dyninfocnt;
693 	uint32_t	rt_relacount;
694 	uint32_t	rt_idx;
695 	uint32_t	rt_lazy;
696 	uint32_t	rt_condvar;
697 	uint32_t	rt_hwcap;
698 	uint32_t	rt_sfcap;
699 	uint32_t	rt_threadid;
700 	uint32_t	rt_cntl;
701 	uint32_t	rt_flags2;
702 } Rt_map32;
703 
704 #endif	/* _SYSCALL32 */
705 
706 /*
707  * Link map state flags.
708  */
709 /*
710  * BEGIN: Exposed to rtld_db - don't move, don't delete
711  */
712 #define	FLG_RT_ISMAIN	0x00000001	/* object represents main executable */
713 #define	FLG_RT_IMGALLOC	0x00000002	/* image is allocated (not mmap'ed) */
714 	/*
715 	 * Available for r_debug version >= RTLD_DB_VERSION5
716 	 */
717 #define	FLG_RT_RELOCED	0x00000004	/* object has been relocated */
718 /*
719  * END: Exposed to rtld_db - don't move, don't delete
720  */
721 #define	FLG_RT_SETGROUP	0x00000008	/* group establishment required */
722 #define	FLG_RT_HWCAP	0x00000010	/* process $HWCAP expansion */
723 #define	FLG_RT_OBJECT	0x00000020	/* object processing (ie. .o's) */
724 #define	FLG_RT_NEWLOAD	0x00000040	/* object is newly loaded */
725 #define	FLG_RT_NODUMP	0x00000080	/* object can't be dldump(3x)'ed */
726 #define	FLG_RT_DELETE	0x00000100	/* object can be deleted */
727 #define	FLG_RT_ANALYZED	0x00000200	/* object has been analyzed */
728 #define	FLG_RT_INITDONE	0x00000400	/* objects .init has been completed */
729 #define	FLG_RT_TRANS	0x00000800	/* object is acting as a translator */
730 #define	FLG_RT_FIXED	0x00001000	/* image location is fixed */
731 #define	FLG_RT_PRELOAD	0x00002000	/* object was preloaded */
732 #define	FLG_RT_ALTER	0x00004000	/* alternative object used */
733 #define	FLG_RT_LOADFLTR	0x00008000	/* trigger filtee loading */
734 #define	FLG_RT_AUDIT	0x00010000	/* object is an auditor */
735 #define	FLG_RT_MODESET	0x00020000	/* MODE() has been initialized */
736 #define	FLG_RT_ANALZING	0x00040000	/* object is being analyzed */
737 #define	FLG_RT_INITFRST 0x00080000	/* execute .init first */
738 #define	FLG_RT_NOOPEN	0x00100000	/* dlopen() not allowed */
739 #define	FLG_RT_FINICLCT	0x00200000	/* fini has been collected (tsort) */
740 #define	FLG_RT_INITCALL	0x00400000	/* objects .init has been called */
741 #define	FLG_RT_SUNWBSS	0x00800000	/* object with PT_SUNWBSS, not mapped */
742 #define	FLG_RT_OBJINTPO	0x01000000	/* object is a global interposer */
743 #define	FLG_RT_SYMINTPO	0x02000000	/* object contains symbol interposer */
744 #define	MSK_RT_INTPOSE	0x03000000	/* mask for all interposer */
745 					/*	possibilities */
746 #define	FLG_RT_MOVE	0x04000000	/* object needs move operation */
747 #define	FLG_RT_TMPLIST	0x08000000	/* object is part of a temporary list */
748 #define	FLG_RT_REGSYMS	0x10000000	/* object has DT_REGISTER entries */
749 #define	FLG_RT_INITCLCT	0x20000000	/* init has been collected (tsort) */
750 #define	FLG_RT_HANDLE	0x40000000	/* generate a handle for this object */
751 #define	FLG_RT_RELOCING	0x80000000	/* object is being relocated */
752 
753 #define	FL1_RT_COPYTOOK	0x00000001	/* copy relocation taken */
754 #define	FL1_RT_RELATIVE	0x00000002	/* relative path expansion required */
755 #define	FL1_RT_CONFSET	0x00000004	/* object was loaded by crle(1) */
756 #define	FL1_RT_NODEFLIB	0x00000008	/* ignore default library search */
757 #define	FL1_RT_ENDFILTE	0x00000010	/* filtee terminates filters search */
758 #define	FL1_RT_DISPREL	0x00000020	/* object has *disp* relocation */
759 #define	FL1_RT_TEXTREL	0x00000040	/* DT_TEXTREL set in object */
760 #define	FL1_RT_INITWAIT	0x00000080	/* threads are waiting on .init */
761 #define	FL1_RT_LDDSTUB	0x00000100	/* identify lddstub */
762 #define	FL1_RT_NOINIFIN	0x00000200	/* no .init or .fini exists */
763 #define	FL1_RT_USED	0x00000400	/* symbol referenced from this object */
764 #define	FL1_RT_SYMBOLIC	0x00000800	/* DF_SYMBOLIC was set - use */
765 					/*	symbolic sym resolution */
766 #define	FL1_RT_OBJSFLTR	0x00001000	/* object is acting as a standard */
767 #define	FL1_RT_OBJAFLTR	0x00002000	/*	or auxiliary filter */
768 #define	FL1_RT_SYMSFLTR	0x00004000	/* symbol is acting as a standard */
769 #define	FL1_RT_SYMAFLTR	0x00008000	/*	or auxiliary filter */
770 #define	MSK_RT_FILTER	0x0000f000	/* mask for all filter possibilities */
771 
772 #define	FL1_RT_TLSADD	0x00010000	/* objects TLS has been registered */
773 #define	FL1_RT_TLSSTAT	0x00020000	/* object requires static TLS */
774 #define	FL1_RT_DIRECT	0x00040000	/* object has DIRECT bindings enabled */
775 #define	FL1_RT_GLOBAUD	0x00080000	/* establish global auditing */
776 
777 /*
778  * The following range of bits are reserved to hold LML_TFLG_AUD_ values
779  * (although the definitions themselves aren't used anywhere).
780  */
781 #define	FL1_AUD_RS_STR	0x00100000	/* RESERVATION start for AU flags */
782 #define	FL1_AUD_RS_END	0x80000000	/* RESERVATION end for AU flags */
783 
784 #define	FL2_RT_DTFLAGS	0x00000001	/* DT_FLAGS element exists */
785 
786 /*
787  * Flags for the tls_modactivity() routine
788  */
789 #define	TM_FLG_MODADD	0x01		/* call tls_modadd() interface */
790 #define	TM_FLG_MODREM	0x02		/* call tls_modrem() interface */
791 
792 /*
793  * Macros for getting to link_map data.
794  */
795 #define	ADDR(X)		((X)->rt_public.l_addr)
796 #define	NAME(X)		((X)->rt_public.l_name)
797 #define	DYN(X)		((X)->rt_public.l_ld)
798 #define	NEXT(X)		((X)->rt_public.l_next)
799 #define	PREV(X)		((X)->rt_public.l_prev)
800 #define	REFNAME(X)	((X)->rt_public.l_refname)
801 
802 /*
803  * Macros for getting to linker private data.
804  */
805 #define	PATHNAME(X)	((X)->rt_pathname)
806 #define	PADSTART(X)	((X)->rt_padstart)
807 #define	PADIMLEN(X)	((X)->rt_padimlen)
808 #define	MSIZE(X)	((X)->rt_msize)
809 #define	FLAGS(X)	((X)->rt_flags)
810 #define	FLAGS1(X)	((X)->rt_flags1)
811 #define	FLAGS2(X)	((X)->rt_flags2)
812 #define	TLSMODID(X)	((X)->rt_tlsmodid)
813 
814 #define	ALIAS(X)	((X)->rt_alias)
815 #define	FPNODE(X)	((X)->rt_fpnode)
816 #define	INIT(X)		((X)->rt_init)
817 #define	FINI(X)		((X)->rt_fini)
818 #define	RPATH(X)	((X)->rt_runpath)
819 #define	RLIST(X)	((X)->rt_runlist)
820 #define	DEPENDS(X)	((X)->rt_depends)
821 #define	CALLERS(X)	((X)->rt_callers)
822 #define	HANDLES(X)	((X)->rt_handles)
823 #define	GROUPS(X)	((X)->rt_groups)
824 #define	ETEXT(X)	((X)->rt_etext)
825 #define	FCT(X)		((X)->rt_fct)
826 #define	SYMINTP(X)	((X)->rt_symintp)
827 #define	LIST(X)		((X)->rt_list)
828 #define	OBJFLTRNDX(X)	((X)->rt_objfltrndx)
829 #define	SYMSFLTRCNT(X)	((X)->rt_symsfltrcnt)
830 #define	SYMAFLTRCNT(X)	((X)->rt_symafltrcnt)
831 #define	MODE(X)		((X)->rt_mode)
832 #define	SORTVAL(X)	((X)->rt_sortval)
833 #define	CYCGROUP(X)	((X)->rt_cycgroup)
834 #define	STDEV(X)	((X)->rt_stdev)
835 #define	STINO(X)	((X)->rt_stino)
836 #define	ORIGNAME(X)	((X)->rt_origname)
837 #define	DIRSZ(X)	((X)->rt_dirsz)
838 #define	COPY_R(X)	((X)->rt_copy.rtc_r)
839 #define	COPY_S(X)	((X)->rt_copy.rtc_s)
840 #define	AUDITORS(X)	((X)->rt_auditors)
841 #define	AUDINFO(X)	((X)->rt_audinfo)
842 #define	SYMINFO(X)	((X)->rt_syminfo)
843 #define	INITARRAY(X)	((X)->rt_initarray)
844 #define	FINIARRAY(X)	((X)->rt_finiarray)
845 #define	PREINITARRAY(X)	((X)->rt_preinitarray)
846 #define	MMAPS(X)	((X)->rt_mmaps)
847 #define	MMAPCNT(X)	((X)->rt_mmapcnt)
848 #define	INITARRAYSZ(X)	((X)->rt_initarraysz)
849 #define	FINIARRAYSZ(X)	((X)->rt_finiarraysz)
850 #define	PREINITARRAYSZ(X) ((X)->rt_preinitarraysz)
851 #define	DYNINFO(X)	((X)->rt_dyninfo)
852 #define	DYNINFOCNT(X)	((X)->rt_dyninfocnt)
853 #define	RELACOUNT(X)	((X)->rt_relacount)
854 #define	IDX(X)		((X)->rt_idx)
855 #define	LAZY(X)		((X)->rt_lazy)
856 #define	CONDVAR(X)	((X)->rt_condvar)
857 #define	CNTL(X)		((X)->rt_cntl)
858 #define	HWCAP(X)	((X)->rt_hwcap)
859 #define	SFCAP(X)	((X)->rt_sfcap)
860 #define	THREADID(X)	((X)->rt_threadid)
861 
862 /*
863  * Flags for tsorting.
864  */
865 #define	RT_SORT_FWD	0x01		/* topological sort (.fini) */
866 #define	RT_SORT_REV	0x02		/* reverse topological sort (.init) */
867 #define	RT_SORT_DELETE	0x10		/* process FLG_RT_DELNEED objects */
868 					/*	only (called via dlclose()) */
869 #define	RT_SORT_INTPOSE	0x20		/* process interposer objects */
870 
871 /*
872  * Flags for lookup_sym (and hence find_sym) routines.
873  */
874 #define	LKUP_DEFT	0x0000		/* simple lookup request */
875 #define	LKUP_SPEC	0x0001		/* special ELF lookup (allows address */
876 					/*	resolutions to plt[] entries) */
877 #define	LKUP_LDOT	0x0002		/* indicates the original A_OUT */
878 					/*	symbol had a leading `.' */
879 #define	LKUP_FIRST	0x0004		/* lookup symbol in first link map */
880 					/*	only */
881 #define	LKUP_COPY	0x0008		/* lookup symbol for a COPY reloc, do */
882 					/*	not bind to symbol at head */
883 #define	LKUP_STDRELOC	0x0010		/* lookup originates from a standard */
884 					/*	relocation (elf_reloc()) */
885 #define	LKUP_SELF	0x0020		/* lookup symbol in ourself - undef */
886 					/*	is valid */
887 #define	LKUP_WEAK	0x0040		/* relocation reference is weak */
888 #define	LKUP_NEXT	0x0080		/* request originates from RTLD_NEXT */
889 #define	LKUP_NODESCENT	0x0100		/* don't descend through dependencies */
890 #define	LKUP_NOFALLBACK	0x0200		/* don't fall back to loading */
891 					/*	pending lazy dependencies */
892 #define	LKUP_DIRECT	0x0400		/* direct binding request */
893 #define	LKUP_SYMNDX	0x0800		/* establish symbol index */
894 #define	LKUP_SINGLETON	0x1000		/* search for a singleton symbol */
895 #define	LKUP_STANDARD	0x2000		/* standard lookup - originated from */
896 					/* 	head link-map element */
897 
898 /*
899  * For the runtime linker to perform a symbol search, a number of data items
900  * related to the search are required.  An Slookup data structure is used to
901  * convey this data to lookup_sym(), and in special cases, to other core
902  * routines that provide the implementation details for lookup_sym()
903  *
904  * The symbol name (sl_name), the caller (sl_cmap), and the link-map from which
905  * to start the search (sl_imap) are fundamental to the symbol search.  The
906  * initial search link-map might get modified by the core routines that provide
907  * the implementation details for lookup_sym().  This modification accommodates
908  * requirements such as processing a handle, direct binding and interposition.
909  * The association between the caller and the potential destination also
910  * determines whether the destination is a candidate to search.
911  *
912  * The lookup identifier (sl_id) is used to identify a runtime linker operation.
913  * Within this operation, any lazy loads that fail are not re-examined.  This
914  * technique keeps the overhead of processing a failed lazy load to a minimum.
915  *
916  * Symbol searches that originate from a relocation record are accompanied by
917  * the relocation index (sl_rsymndx), the symbol reference (sl_rsym) and
918  * possibly the relocation type (sl_rtype).  This data provides for determining
919  * lazy loading, direct binding, and special symbol processing requirements
920  * such as copy relocations and singleton lookup.
921  *
922  * The symbols hash value is computed by lookup_sym, and propagated throughout
923  * the search engine.  Note, occasionally the Slookup data is passed to a core
924  * routine that provides the implementation details for lookup_sym(), ie.
925  * elf_find_sym(), in which case the caller must initialize the hash value.
926  *
927  * The symbols binding information is established by lookup_sym() when the
928  * symbols relocation type is supplied.  Weak bindings allow relocations to
929  * be set to zero should a symbol lookup fail.
930  *
931  * The flags allow the caller to control aspects of the search, including the
932  * interpretation of copy relocations, etc.  Note, a number of flag settings
933  * are established in lookup_sym() from attributes of the symbol reference.
934  */
935 typedef struct {
936 	const char	*sl_name;	/* symbol name */
937 	Rt_map		*sl_cmap;	/* callers link-map */
938 	Rt_map		*sl_imap;	/* initial link-map to search */
939 	ulong_t		sl_id;		/* identifier for this lookup */
940 	ulong_t		sl_hash;	/* symbol hash value */
941 	ulong_t		sl_rsymndx;	/* referencing reloc symndx */
942 	Sym		*sl_rsym;	/* referencing symbol */
943 	uchar_t		sl_rtype;	/* relocation type associate with */
944 					/*    symbol */
945 	uchar_t		sl_bind;	/* symbols binding (returned) */
946 	uint_t		sl_flags;	/* lookup flags */
947 } Slookup;
948 
949 #define	SLOOKUP_INIT(sl, name, cmap, imap, id, hash, rsymndx, rsym, rtype, \
950     flags) \
951 	(void) (sl.sl_name = (name), sl.sl_cmap = (cmap), sl.sl_imap = (imap), \
952 	    sl.sl_id = (id), sl.sl_hash = (hash), sl.sl_rsymndx = (rsymndx), \
953 	    sl.sl_rsym = (rsym), sl.sl_rtype = (rtype), sl.sl_bind = 0, \
954 	    sl.sl_flags = (flags))
955 
956 /*
957  * Define a number of .plt lookup outcomes, for use in binding diagnostics.
958  */
959 typedef	enum {
960 	PLT_T_NONE = 0,
961 	PLT_T_21D,
962 	PLT_T_24D,
963 	PLT_T_U32,
964 	PLT_T_U44,
965 	PLT_T_FULL,
966 	PLT_T_FAR,
967 	PLT_T_NUM			/* Must be last */
968 } Pltbindtype;
969 
970 /*
971  * Prototypes.
972  */
973 extern ulong_t		ld_entry_cnt;	/* counter bumped on each entry to */
974 					/*    ld.so.1. */
975 extern Lm_list		lml_main;	/* main's link map list */
976 extern Lm_list		lml_rtld;	/* rtld's link map list */
977 extern Lm_list		*lml_list[];
978 
979 extern Pltbindtype	elf_plt_write(uintptr_t, uintptr_t, void *, uintptr_t,
980 			    Xword);
981 extern Rt_map		*is_so_loaded(Lm_list *, const char *, int *);
982 extern Sym		*lookup_sym(Slookup *, Rt_map **, uint_t *, int *);
983 extern int		rt_dldump(Rt_map *, const char *, int, Addr);
984 
985 #ifdef	__cplusplus
986 }
987 #endif
988 
989 #endif /* _RTLD_H */
990