rtld.h revision 6206:6b0ed502a8e7
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
49extern "C" {
50#endif
51
52
53/*
54 * Linked list of directories or filenames (built from colon separated string).
55 */
56typedef 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
65typedef 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 */
71typedef 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
128typedef 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
136typedef 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 */
155typedef 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 */
246typedef 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
258struct 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
287struct 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 */
435typedef 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 */
459typedef 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 */
481typedef struct {
482	union {
483		mutex_t		l_mutex;
484		rwlock_t	l_rwlock;
485	} u;
486} Rt_lock;
487
488typedef	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 */
495typedef 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 for pathnames of objects
518 * loaded into memory
519 */
520typedef struct {
521	const char	*fpn_name;	/* object name */
522	Rt_map		*fpn_lmp;	/* object link-map */
523	avl_node_t	fpn_avl;	/* avl book-keeping (see SGSOFFSETOF) */
524	uint_t		fpn_hash;	/* object name hash value */
525} FullpathNode;
526
527/*
528 * Define a mapping structure, which is maintained to describe each mapping
529 * of an object, ie. the text segment, data segment, bss segment, etc.
530 */
531typedef struct {
532	caddr_t		m_vaddr;	/* mapping address */
533	size_t		m_fsize;	/* backing file size */
534	size_t		m_msize;	/* mapping size */
535	int		m_perm;		/* mapping permissions */
536} Mmap;
537
538/*
539 * A given link-map can hold either a supplier or receiver copy
540 * relocation list, but not both. This union is used to overlap
541 * the space used for the two lists.
542 */
543typedef union {
544	Alist	*rtc_r;		/* receiver list (Rel_copy) */
545	APlist	*rtc_s;		/* supplier list (Rt_map *) */
546} Rt_map_copy;
547
548
549/*
550 * Link-map definition.
551 */
552struct rt_map {
553	/*
554	 * BEGIN: Exposed to rtld_db - don't move, don't delete
555	 */
556	Link_map	rt_public;	/* public data */
557	char		*rt_pathname;	/* full pathname of loaded object */
558	ulong_t		rt_padstart;	/* start of image (including padding) */
559	ulong_t		rt_padimlen;	/* size of image (including padding */
560	ulong_t		rt_msize;	/* total memory mapped */
561	uint_t		rt_flags;	/* state flags, see FLG below */
562	uint_t		rt_flags1;	/* state flags1, see FL1 below */
563	ulong_t		rt_tlsmodid;	/* TLS module id */
564	/*
565	 * END: Exposed to rtld_db - don't move, don't delete
566	 */
567	APlist		*rt_alias;	/* list of linked file names */
568	APlist		*rt_fpnode;	/* list of FullpathNode AVL nodes */
569	void		(*rt_init)();	/* address of _init */
570	void		(*rt_fini)();	/* address of _fini */
571	char		*rt_runpath;	/* LD_RUN_PATH and its equivalent */
572	Pnode		*rt_runlist;	/*	Pnode structures */
573	APlist		*rt_depends;	/* list of dependencies */
574	APlist		*rt_callers;	/* list of callers */
575	APlist		*rt_handles;	/* dlopen handles */
576	APlist		*rt_groups;	/* groups we're a member of */
577	ulong_t		rt_etext;	/* etext address */
578	struct fct	*rt_fct;	/* file class table for this object */
579	Sym		*(*rt_symintp)(); /* link map symbol interpreter */
580	void		*rt_priv;	/* private data, object type specific */
581	Lm_list		*rt_list;	/* link map list we belong to */
582	uint_t		rt_objfltrndx;	/* object filtees .dynamic index */
583	uint_t		rt_symsfltrcnt;	/* number of standard symbol filtees */
584	uint_t		rt_symafltrcnt;	/* number of auxiliary symbol filtees */
585	int		rt_mode;	/* usage mode, see RTLD mode flags */
586	int		rt_sortval;	/* temporary buffer to traverse graph */
587	uint_t		rt_cycgroup;	/* cyclic group */
588	dev_t		rt_stdev;	/* device id and inode number for .so */
589	ino_t		rt_stino;	/*	multiple inclusion checks */
590	char		*rt_origname;	/* original pathname of loaded object */
591	size_t		rt_dirsz;	/*	and its size */
592	Rt_map_copy	rt_copy;	/* list of copy relocations */
593	Audit_desc	*rt_auditors;	/* audit descriptor array */
594	Audit_info	*rt_audinfo;	/* audit information descriptor */
595	Syminfo		*rt_syminfo;	/* elf .syminfo section - here */
596					/*	because it is checked in */
597					/*	common code */
598	Addr		*rt_initarray;	/* .initarray table */
599	Addr		*rt_finiarray;	/* .finiarray table */
600	Addr		*rt_preinitarray; /* .preinitarray table */
601	Mmap		*rt_mmaps;	/* array of mapping information */
602	uint_t		rt_mmapcnt;	/*	and associated number */
603	uint_t		rt_initarraysz;	/* size of .initarray table */
604	uint_t		rt_finiarraysz;	/* size of .finiarray table */
605	uint_t		rt_preinitarraysz; /* size of .preinitarray table */
606	Dyninfo		*rt_dyninfo;	/* .dynamic information descriptors */
607	uint_t		rt_dyninfocnt;	/* count of dyninfo entries */
608	uint_t		rt_relacount;	/* no. of RELATIVE relocations */
609	uint_t		rt_idx;		/* hold index within linkmap list */
610	uint_t		rt_lazy;	/* lazy dependencies pending */
611	Rt_cond		*rt_condvar;	/*	variables */
612	Xword		rt_hwcap;	/* hardware capabilities */
613	Xword		rt_sfcap;	/* software capabilities */
614	thread_t	rt_threadid;	/* thread init/fini synchronization */
615	uint_t		rt_cntl;	/* link-map control list we belong to */
616	uint_t		rt_flags2;	/* state flags2, see FL2 below */
617};
618
619
620#ifdef _SYSCALL32
621/*
622 * Structure to allow 64-bit rtld_db to read 32-bit processes out of procfs.
623 */
624typedef union {
625	uint32_t	rtc_r;
626	uint32_t	rtc_s;
627} Rt_map_copy32;
628
629typedef struct rt_map32 {
630	/*
631	 * BEGIN: Exposed to rtld_db - don't move, don't delete
632	 */
633	Link_map32	rt_public;
634	uint32_t	rt_pathname;
635	uint32_t	rt_padstart;
636	uint32_t	rt_padimlen;
637	uint32_t	rt_msize;
638	uint32_t	rt_flags;
639	uint32_t	rt_flags1;
640	uint32_t	rt_tlsmodid;
641	/*
642	 * END: Exposed to rtld_db - don't move, don't delete
643	 */
644	uint32_t	rt_alias;
645	uint32_t	rt_fpnode;
646	uint32_t 	rt_init;
647	uint32_t	rt_fini;
648	uint32_t	rt_runpath;
649	uint32_t	rt_runlist;
650	uint32_t	rt_depends;
651	uint32_t	rt_callers;
652	uint32_t	rt_handles;
653	uint32_t	rt_groups;
654	uint32_t	rt_etext;
655	uint32_t	rt_fct;
656	uint32_t	rt_symintp;
657	uint32_t	rt_priv;
658	uint32_t 	rt_list;
659	uint32_t 	rt_objfltrndx;
660	uint32_t 	rt_symsfltrcnt;
661	uint32_t 	rt_symafltrcnt;
662	int32_t		rt_mode;
663	int32_t		rt_sortval;
664	uint32_t	rt_cycgroup;
665	uint32_t	rt_stdev;
666	uint32_t	rt_stino;
667	uint32_t	rt_origname;
668	uint32_t	rt_dirsz;
669	Rt_map_copy32	rt_copy;
670	uint32_t 	rt_auditors;
671	uint32_t 	rt_audinfo;
672	uint32_t	rt_syminfo;
673	uint32_t	rt_initarray;
674	uint32_t	rt_finiarray;
675	uint32_t	rt_preinitarray;
676	uint32_t	rt_mmaps;
677	uint32_t	rt_mmapcnt;
678	uint32_t	rt_initarraysz;
679	uint32_t	rt_finiarraysz;
680	uint32_t	rt_preinitarraysz;
681	uint32_t 	rt_dyninfo;
682	uint32_t 	rt_dyninfocnt;
683	uint32_t	rt_relacount;
684	uint32_t	rt_idx;
685	uint32_t	rt_lazy;
686	uint32_t	rt_condvar;
687	uint32_t	rt_hwcap;
688	uint32_t	rt_sfcap;
689	uint32_t	rt_threadid;
690	uint32_t	rt_cntl;
691	uint32_t	rt_flags2;
692} Rt_map32;
693
694#endif	/* _SYSCALL32 */
695
696/*
697 * Link map state flags.
698 */
699/*
700 * BEGIN: Exposed to rtld_db - don't move, don't delete
701 */
702#define	FLG_RT_ISMAIN	0x00000001	/* object represents main executable */
703#define	FLG_RT_IMGALLOC	0x00000002	/* image is allocated (not mmap'ed) */
704	/*
705	 * Available for r_debug version >= RTLD_DB_VERSION5
706	 */
707#define	FLG_RT_RELOCED	0x00000004	/* object has been relocated */
708/*
709 * END: Exposed to rtld_db - don't move, don't delete
710 */
711#define	FLG_RT_SETGROUP	0x00000008	/* group establishment required */
712#define	FLG_RT_HWCAP	0x00000010	/* process $HWCAP expansion */
713#define	FLG_RT_OBJECT	0x00000020	/* object processing (ie. .o's) */
714#define	FLG_RT_NEWLOAD	0x00000040	/* object is newly loaded */
715#define	FLG_RT_NODUMP	0x00000080	/* object can't be dldump(3x)'ed */
716#define	FLG_RT_DELETE	0x00000100	/* object can be deleted */
717#define	FLG_RT_ANALYZED	0x00000200	/* object has been analyzed */
718#define	FLG_RT_INITDONE	0x00000400	/* objects .init has been completed */
719#define	FLG_RT_TRANS	0x00000800	/* object is acting as a translator */
720#define	FLG_RT_FIXED	0x00001000	/* image location is fixed */
721#define	FLG_RT_PRELOAD	0x00002000	/* object was preloaded */
722#define	FLG_RT_ALTER	0x00004000	/* alternative object used */
723#define	FLG_RT_LOADFLTR	0x00008000	/* trigger filtee loading */
724#define	FLG_RT_AUDIT	0x00010000	/* object is an auditor */
725#define	FLG_RT_MODESET	0x00020000	/* MODE() has been initialized */
726#define	FLG_RT_ANALZING	0x00040000	/* object is being analyzed */
727#define	FLG_RT_INITFRST 0x00080000	/* execute .init first */
728#define	FLG_RT_NOOPEN	0x00100000	/* dlopen() not allowed */
729#define	FLG_RT_FINICLCT	0x00200000	/* fini has been collected (tsort) */
730#define	FLG_RT_INITCALL	0x00400000	/* objects .init has been called */
731#define	FLG_RT_SUNWBSS	0x00800000	/* object with PT_SUNWBSS, not mapped */
732#define	FLG_RT_OBJINTPO	0x01000000	/* object is a global interposer */
733#define	FLG_RT_SYMINTPO	0x02000000	/* object contains symbol interposer */
734#define	MSK_RT_INTPOSE	0x03000000	/* mask for all interposer */
735					/*	possibilities */
736#define	FLG_RT_MOVE	0x04000000	/* object needs move operation */
737#define	FLG_RT_TMPLIST	0x08000000	/* object is part of a temporary list */
738#define	FLG_RT_REGSYMS	0x10000000	/* object has DT_REGISTER entries */
739#define	FLG_RT_INITCLCT	0x20000000	/* init has been collected (tsort) */
740#define	FLG_RT_HANDLE	0x40000000	/* generate a handle for this object */
741#define	FLG_RT_RELOCING	0x80000000	/* object is being relocated */
742
743#define	FL1_RT_COPYTOOK	0x00000001	/* copy relocation taken */
744#define	FL1_RT_RELATIVE	0x00000002	/* relative path expansion required */
745#define	FL1_RT_CONFSET	0x00000004	/* object was loaded by crle(1) */
746#define	FL1_RT_NODEFLIB	0x00000008	/* ignore default library search */
747#define	FL1_RT_ENDFILTE	0x00000010	/* filtee terminates filters search */
748#define	FL1_RT_DISPREL	0x00000020	/* object has *disp* relocation */
749#define	FL1_RT_TEXTREL	0x00000040	/* DT_TEXTREL set in object */
750#define	FL1_RT_INITWAIT	0x00000080	/* threads are waiting on .init */
751#define	FL1_RT_LDDSTUB	0x00000100	/* identify lddstub */
752#define	FL1_RT_NOINIFIN	0x00000200	/* no .init or .fini exists */
753#define	FL1_RT_USED	0x00000400	/* symbol referenced from this object */
754#define	FL1_RT_SYMBOLIC	0x00000800	/* DF_SYMBOLIC was set - use */
755					/*	symbolic sym resolution */
756#define	FL1_RT_OBJSFLTR	0x00001000	/* object is acting as a standard */
757#define	FL1_RT_OBJAFLTR	0x00002000	/*	or auxiliary filter */
758#define	FL1_RT_SYMSFLTR	0x00004000	/* symbol is acting as a standard */
759#define	FL1_RT_SYMAFLTR	0x00008000	/*	or auxiliary filter */
760#define	MSK_RT_FILTER	0x0000f000	/* mask for all filter possibilities */
761
762#define	FL1_RT_TLSADD	0x00010000	/* objects TLS has been registered */
763#define	FL1_RT_TLSSTAT	0x00020000	/* object requires static TLS */
764#define	FL1_RT_DIRECT	0x00040000	/* object has DIRECT bindings enabled */
765#define	FL1_RT_GLOBAUD	0x00080000	/* establish global auditing */
766
767/*
768 * The following range of bits are reserved to hold LML_TFLG_AUD_ values
769 * (although the definitions themselves aren't used anywhere).
770 */
771#define	FL1_AUD_RS_STR	0x00100000	/* RESERVATION start for AU flags */
772#define	FL1_AUD_RS_END	0x80000000	/* RESERVATION end for AU flags */
773
774#define	FL2_RT_DTFLAGS	0x00000001	/* DT_FLAGS element exists */
775
776/*
777 * Flags for the tls_modactivity() routine
778 */
779#define	TM_FLG_MODADD	0x01		/* call tls_modadd() interface */
780#define	TM_FLG_MODREM	0x02		/* call tls_modrem() interface */
781
782/*
783 * Macros for getting to link_map data.
784 */
785#define	ADDR(X)		((X)->rt_public.l_addr)
786#define	NAME(X)		((X)->rt_public.l_name)
787#define	DYN(X)		((X)->rt_public.l_ld)
788#define	NEXT(X)		((X)->rt_public.l_next)
789#define	PREV(X)		((X)->rt_public.l_prev)
790#define	REFNAME(X)	((X)->rt_public.l_refname)
791
792/*
793 * Macros for getting to linker private data.
794 */
795#define	PATHNAME(X)	((X)->rt_pathname)
796#define	PADSTART(X)	((X)->rt_padstart)
797#define	PADIMLEN(X)	((X)->rt_padimlen)
798#define	MSIZE(X)	((X)->rt_msize)
799#define	FLAGS(X)	((X)->rt_flags)
800#define	FLAGS1(X)	((X)->rt_flags1)
801#define	FLAGS2(X)	((X)->rt_flags2)
802#define	TLSMODID(X)	((X)->rt_tlsmodid)
803
804#define	ALIAS(X)	((X)->rt_alias)
805#define	FPNODE(X)	((X)->rt_fpnode)
806#define	INIT(X)		((X)->rt_init)
807#define	FINI(X)		((X)->rt_fini)
808#define	RPATH(X)	((X)->rt_runpath)
809#define	RLIST(X)	((X)->rt_runlist)
810#define	DEPENDS(X)	((X)->rt_depends)
811#define	CALLERS(X)	((X)->rt_callers)
812#define	HANDLES(X)	((X)->rt_handles)
813#define	GROUPS(X)	((X)->rt_groups)
814#define	ETEXT(X)	((X)->rt_etext)
815#define	FCT(X)		((X)->rt_fct)
816#define	SYMINTP(X)	((X)->rt_symintp)
817#define	LIST(X)		((X)->rt_list)
818#define	OBJFLTRNDX(X)	((X)->rt_objfltrndx)
819#define	SYMSFLTRCNT(X)	((X)->rt_symsfltrcnt)
820#define	SYMAFLTRCNT(X)	((X)->rt_symafltrcnt)
821#define	MODE(X)		((X)->rt_mode)
822#define	SORTVAL(X)	((X)->rt_sortval)
823#define	CYCGROUP(X)	((X)->rt_cycgroup)
824#define	STDEV(X)	((X)->rt_stdev)
825#define	STINO(X)	((X)->rt_stino)
826#define	ORIGNAME(X)	((X)->rt_origname)
827#define	DIRSZ(X)	((X)->rt_dirsz)
828#define	COPY_R(X)	((X)->rt_copy.rtc_r)
829#define	COPY_S(X)	((X)->rt_copy.rtc_s)
830#define	AUDITORS(X)	((X)->rt_auditors)
831#define	AUDINFO(X)	((X)->rt_audinfo)
832#define	SYMINFO(X)	((X)->rt_syminfo)
833#define	INITARRAY(X)	((X)->rt_initarray)
834#define	FINIARRAY(X)	((X)->rt_finiarray)
835#define	PREINITARRAY(X)	((X)->rt_preinitarray)
836#define	MMAPS(X)	((X)->rt_mmaps)
837#define	MMAPCNT(X)	((X)->rt_mmapcnt)
838#define	INITARRAYSZ(X)	((X)->rt_initarraysz)
839#define	FINIARRAYSZ(X)	((X)->rt_finiarraysz)
840#define	PREINITARRAYSZ(X) ((X)->rt_preinitarraysz)
841#define	DYNINFO(X)	((X)->rt_dyninfo)
842#define	DYNINFOCNT(X)	((X)->rt_dyninfocnt)
843#define	RELACOUNT(X)	((X)->rt_relacount)
844#define	IDX(X)		((X)->rt_idx)
845#define	LAZY(X)		((X)->rt_lazy)
846#define	CONDVAR(X)	((X)->rt_condvar)
847#define	CNTL(X)		((X)->rt_cntl)
848#define	HWCAP(X)	((X)->rt_hwcap)
849#define	SFCAP(X)	((X)->rt_sfcap)
850#define	THREADID(X)	((X)->rt_threadid)
851
852/*
853 * Flags for tsorting.
854 */
855#define	RT_SORT_FWD	0x01		/* topological sort (.fini) */
856#define	RT_SORT_REV	0x02		/* reverse topological sort (.init) */
857#define	RT_SORT_DELETE	0x10		/* process FLG_RT_DELNEED objects */
858					/*	only (called via dlclose()) */
859#define	RT_SORT_INTPOSE	0x20		/* process interposer objects */
860
861/*
862 * Flags for lookup_sym (and hence find_sym) routines.
863 */
864#define	LKUP_DEFT	0x0000		/* simple lookup request */
865#define	LKUP_SPEC	0x0001		/* special ELF lookup (allows address */
866					/*	resolutions to plt[] entries) */
867#define	LKUP_LDOT	0x0002		/* indicates the original A_OUT */
868					/*	symbol had a leading `.' */
869#define	LKUP_FIRST	0x0004		/* lookup symbol in first link map */
870					/*	only */
871#define	LKUP_COPY	0x0008		/* lookup symbol for a COPY reloc, do */
872					/*	not bind to symbol at head */
873#define	LKUP_STDRELOC	0x0010		/* lookup originates from a standard */
874					/*	relocation (elf_reloc()) */
875#define	LKUP_SELF	0x0020		/* lookup symbol in ourself - undef */
876					/*	is valid */
877#define	LKUP_WEAK	0x0040		/* relocation reference is weak */
878#define	LKUP_NEXT	0x0080		/* request originates from RTLD_NEXT */
879#define	LKUP_NODESCENT	0x0100		/* don't descend through dependencies */
880#define	LKUP_NOFALLBACK	0x0200		/* don't fall back to loading */
881					/*	pending lazy dependencies */
882#define	LKUP_DIRECT	0x0400		/* direct binding request */
883#define	LKUP_SYMNDX	0x0800		/* establish symbol index */
884#define	LKUP_SINGLETON	0x1000		/* search for a singleton symbol */
885#define	LKUP_STANDARD	0x2000		/* standard lookup - originated from */
886					/* 	head link-map element */
887
888/*
889 * For the runtime linker to perform a symbol search, a number of data items
890 * related to the search are required.  An Slookup data structure is used to
891 * convey this data to lookup_sym(), and in special cases, to other core
892 * routines that provide the implementation details for lookup_sym()
893 *
894 * The symbol name (sl_name), the caller (sl_cmap), and the link-map from which
895 * to start the search (sl_imap) are fundamental to the symbol search.  The
896 * initial search link-map might get modified by the core routines that provide
897 * the implementation details for lookup_sym().  This modification accommodates
898 * requirements such as processing a handle, direct binding and interposition.
899 * The association between the caller and the potential destination also
900 * determines whether the destination is a candidate to search.
901 *
902 * The lookup identifier (sl_id) is used to identify a runtime linker operation.
903 * Within this operation, any lazy loads that fail are not re-examined.  This
904 * technique keeps the overhead of processing a failed lazy load to a minimum.
905 *
906 * Symbol searches that originate from a relocation record are accompanied by
907 * the relocation index (sl_rsymndx), the symbol reference (sl_rsym) and
908 * possibly the relocation type (sl_rtype).  This data provides for determining
909 * lazy loading, direct binding, and special symbol processing requirements
910 * such as copy relocations and singleton lookup.
911 *
912 * The symbols hash value is computed by lookup_sym, and propagated throughout
913 * the search engine.  Note, occasionally the Slookup data is passed to a core
914 * routine that provides the implementation details for lookup_sym(), ie.
915 * elf_find_sym(), in which case the caller must initialize the hash value.
916 *
917 * The symbols binding information is established by lookup_sym() when the
918 * symbols relocation type is supplied.  Weak bindings allow relocations to
919 * be set to zero should a symbol lookup fail.
920 *
921 * The flags allow the caller to control aspects of the search, including the
922 * interpretation of copy relocations, etc.  Note, a number of flag settings
923 * are established in lookup_sym() from attributes of the symbol reference.
924 */
925typedef struct {
926	const char	*sl_name;	/* symbol name */
927	Rt_map		*sl_cmap;	/* callers link-map */
928	Rt_map		*sl_imap;	/* initial link-map to search */
929	ulong_t		sl_id;		/* identifier for this lookup */
930	ulong_t		sl_hash;	/* symbol hash value */
931	ulong_t		sl_rsymndx;	/* referencing reloc symndx */
932	Sym		*sl_rsym;	/* referencing symbol */
933	uchar_t		sl_rtype;	/* relocation type associate with */
934					/*    symbol */
935	uchar_t		sl_bind;	/* symbols binding (returned) */
936	uint_t		sl_flags;	/* lookup flags */
937} Slookup;
938
939#define	SLOOKUP_INIT(sl, name, cmap, imap, id, hash, rsymndx, rsym, rtype, \
940    flags) \
941	(void) (sl.sl_name = (name), sl.sl_cmap = (cmap), sl.sl_imap = (imap), \
942	    sl.sl_id = (id), sl.sl_hash = (hash), sl.sl_rsymndx = (rsymndx), \
943	    sl.sl_rsym = (rsym), sl.sl_rtype = (rtype), sl.sl_bind = 0, \
944	    sl.sl_flags = (flags))
945
946/*
947 * Define a number of .plt lookup outcomes, for use in binding diagnostics.
948 */
949typedef	enum {
950	PLT_T_NONE = 0,
951	PLT_T_21D,
952	PLT_T_24D,
953	PLT_T_U32,
954	PLT_T_U44,
955	PLT_T_FULL,
956	PLT_T_FAR,
957	PLT_T_NUM			/* Must be last */
958} Pltbindtype;
959
960/*
961 * Prototypes.
962 */
963extern ulong_t		ld_entry_cnt;	/* counter bumped on each entry to */
964					/*    ld.so.1. */
965extern Lm_list		lml_main;	/* main's link map list */
966extern Lm_list		lml_rtld;	/* rtld's link map list */
967extern Lm_list		*lml_list[];
968
969extern Pltbindtype	elf_plt_write(uintptr_t, uintptr_t, void *, uintptr_t,
970			    Xword);
971extern Rt_map		*is_so_loaded(Lm_list *, const char *);
972extern Sym		*lookup_sym(Slookup *, Rt_map **, uint_t *);
973extern int		rt_dldump(Rt_map *, const char *, int, Addr);
974
975#ifdef	__cplusplus
976}
977#endif
978
979#endif /* _RTLD_H */
980