xref: /titanic_41/usr/src/cmd/sgs/rtld/common/_a.out.h (revision 6a634c9dca3093f3922e4b7ab826d7bdf17bf78e)
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) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 #ifndef	_A_DOT_OUT_DOT_H
26 #define	_A_DOT_OUT_DOT_H
27 
28 #include <sys/types.h>
29 #include <sys/mman.h>
30 #include <a.out.h>
31 #include <_rtld.h>
32 
33 #ifdef	__cplusplus
34 extern "C" {
35 #endif
36 
37 #define	max(a, b)	((a) < (b) ? (b) : (a))
38 
39 typedef struct link_dynamic	Link_dynamic;
40 
41 /*
42  * Extern functions for a.out format file class.
43  */
44 extern	ulong_t	aout_bndr(caddr_t);
45 extern	int	aout_get_mmap(Lm_list *, mmapobj_result_t *);
46 extern	int	aout_lookup_sym(Slookup *, Sresult *, uint_t *, int *);
47 extern	Rt_map	*aout_new_lmp(Lm_list *, Aliste, Fdesc *, Addr, size_t, void *,
48 		    Rt_map *, int *);
49 extern	void	aout_plt_write(caddr_t, ulong_t);
50 extern	int	aout_reloc(Rt_map *, uint_t, int *, APlist **);
51 extern	void	aout_rtbndr(caddr_t);
52 extern	Fct	*aout_verify(caddr_t, size_t, Fdesc *, const char *,
53 		    Rej_desc *);
54 
55 /*
56  * Private data for an a.out format file class.
57  */
58 typedef struct _rt_aout_private {
59 	struct link_dynamic	*lm_ld;		/* 4.x aout dynamic pointer */
60 	struct ld_private	*lm_lpd;	/* private aout object area */
61 } Rt_aoutp;
62 
63 /*
64  * Special defines for a.out format file class.
65  */
66 #ifndef NULL
67 #define	NULL	0
68 #endif
69 #define	N_UNDF	0x0		/* undefined */
70 #define	N_ABS	0x2		/* absolute */
71 #define	N_COMM	0x12		/* common (internal to ld) */
72 #define	N_EXT	01		/* external bit, or'ed in */
73 
74 /*
75  * Format of a symbol table entry.
76  */
77 struct	nlist {
78 	union {
79 		char	*n_name;		/* for use when in-core */
80 		long	n_strx;		/* index into file string table */
81 	} n_un;
82 	uchar_t 	n_type;		/* type flag (N_TEXT,..)  */
83 	char		n_other;	/* unused */
84 	short		n_desc;		/* see <stab.h> */
85 	ulong_t		n_value;	/* value of symbol (or sdb offset) */
86 };
87 
88 /*
89  * Link editor public definitions.
90  */
91 
92 #ifndef _link_h
93 #define	_link_h
94 
95 /*
96  * Structure describing logical name and requirements on an object
97  * which is to be loaded dynamically.
98  */
99 struct old_link_object {
100 	char	*lo_name;		/* name of object */
101 	int	lo_library : 1,		/* searched for by library rules */
102 		lo_unused : 31;
103 	short	lo_major;		/* major version number */
104 	short	lo_minor;		/* minor version number */
105 };
106 
107 struct link_object {
108 	long	lo_name;		/* name (often relative) */
109 	int	lo_library : 1,		/* searched for by library rules */
110 		lo_unused : 31;
111 	short	lo_major;		/* major version number */
112 	short	lo_minor;		/* minor version number */
113 	long	lo_next;		/* next one (often relative) */
114 };
115 typedef	struct	link_object Lnk_obj;
116 
117 /*
118  * Structure describing name and placement of dynamically loaded
119  * objects in a process' address space.
120  */
121 typedef struct a_link_map	A_link_map;
122 
123 struct a_link_map {
124 	caddr_t	lm_addr;		/* address at which object mapped */
125 	char	*lm_name;		/* full name of loaded object */
126 	struct	a_link_map *lm_next;	/* next object in map */
127 	struct	link_object *lm_lop;	/* link object that got us here */
128 	caddr_t lm_lob;			/* base address for said link object */
129 	int	lm_rwt : 1;		/* text is read/write */
130 	struct	link_dynamic *lm_ld;	/* dynamic structure */
131 	caddr_t	lm_lpd;			/* loader private data */
132 };
133 
134 /*
135  * Version 1 of dynamic linking information.  With the exception of
136  * ld_loaded (determined at execution time) and ld_stab_hash (a special
137  * case of relocation handled at execution time), the values in this
138  * structure reflect offsets from the containing link_dynamic structure.
139  */
140 struct link_dynamic_1 {
141 	struct	a_link_map *ld_loaded;	/* list of loaded objects */
142 	long	ld_need;		/* list of needed objects */
143 	long	ld_rules;		/* search rules for library objects */
144 	long	ld_got;			/* global offset table */
145 	long	ld_plt;			/* procedure linkage table */
146 	long	ld_rel;			/* relocation table */
147 	long	ld_hash;		/* symbol hash table */
148 	long	ld_stab;		/* symbol table itself */
149 	long	(*ld_stab_hash)();	/* "pointer" to symbol hash function */
150 	long	ld_buckets;		/* number of hash buckets */
151 	long	ld_symbols;		/* symbol strings */
152 	long	ld_symb_size;		/* size of symbol strings */
153 	long	ld_text;		/* size of text area */
154 };
155 
156 struct link_dynamic_2 {
157 	struct	a_link_map *ld_loaded;	/* list of loaded objects */
158 	long	ld_need;		/* list of needed objects */
159 	long	ld_rules;		/* search rules for library objects */
160 	long	ld_got;			/* global offset table */
161 	long	ld_plt;			/* procedure linkage table */
162 	long	ld_rel;			/* relocation table */
163 	long	ld_hash;		/* symbol hash table */
164 	long	ld_stab;		/* symbol table itself */
165 	long	(*ld_stab_hash)();	/* "pointer" to symbol hash function */
166 	long	ld_buckets;		/* number of hash buckets */
167 	long	ld_symbols;		/* symbol strings */
168 	long	ld_symb_size;		/* size of symbol strings */
169 	long	ld_text;		/* size of text area */
170 	long	ld_plt_sz;		/* size of procedure linkage table */
171 };
172 
173 /*
174  * Structure pointing to run time allocated common symbols and
175  * its string.
176  */
177 struct rtc_symb {
178 	struct	nlist *rtc_sp;		/* symbol for common */
179 	struct	rtc_symb *rtc_next;	/* next common */
180 };
181 
182 /*
183  * Debugger interface structure.
184  */
185 struct 	ld_debug {
186 	int	ldd_version;		/* version # of interface */
187 	int	ldd_in_debugger;	/* a debugger is running us */
188 	int	ldd_sym_loaded;		/* we loaded some symbols */
189 	char    *ldd_bp_addr;		/* place for ld-generated bpt */
190 	int	ldd_bp_inst;		/* instruction which was there */
191 	struct rtc_symb *ldd_cp;	/* commons we built */
192 };
193 
194 /*
195  * Structure associated with each object which may be or which requires
196  * execution-time link editing.  Used by the run-time linkage editor to
197  * identify needed objects and symbol definitions and references.
198  */
199 struct 	old_link_dynamic {
200 	int	ld_version;		/* version # of this structure */
201 	union {
202 		struct link_dynamic_1 ld_1;
203 	} ld_un;
204 
205 	int	in_debugging;
206 	int	sym_loaded;
207 	char    *bp_addr;
208 	int	bp_inst;
209 	struct rtc_symb *cp; 		/* pointer to an array of runtime */
210 					/* allocated common symbols. */
211 };
212 
213 struct	link_dynamic {
214 	int	ld_version;		/* version # of this structure */
215 	struct 	ld_debug *ldd;
216 	union {
217 		struct link_dynamic_1 *ld_1;
218 		struct link_dynamic_2 *ld_2;
219 	} ld_un;
220 };
221 
222 
223 /*
224  * Get size of relocations.
225  */
226 #define	GETGOTSZ(x)	(x->ld_version < 2 ?				\
227 			((struct old_link_dynamic *)x)->v1.ld_plt -	\
228 			((struct old_link_dynamic *)x)->v1.ld_got :	\
229 			(x)->v2->ld_plt - (x)->v2->ld_got)
230 
231 #define	GETPLTSZ(x)	(x->ld_version < 2 ?				\
232 			((struct old_link_dynamic *)x)->v1.ld_rel -	\
233 			((struct old_link_dynamic *)x)->v1.ld_plt :	\
234 			(x)->v2->ld_rel - (x)->v2->ld_plt)
235 
236 #define	GETRELSZ(x)	(x->ld_version < 2 ?				\
237 			((struct old_link_dynamic *)x)->v1.ld_hash -	\
238 			((struct old_link_dynamic *)x)->v1.ld_rel :	\
239 			(x)->v2->ld_hash - (x)->v2->ld_rel)
240 
241 #define	GETHASHSZ(x)	(x->ld_version < 2 ?				\
242 			((struct old_link_dynamic *)x)->v1.ld_stab -	\
243 			((struct old_link_dynamic *)x)->v1.ld_hash :	\
244 			(x)->v2->ld_stab - (x)->v2->ld_hash)
245 
246 #define	GETSTABSZ(x)	(x->ld_version < 2 ?				\
247 			((struct old_link_dynamic *)x)->v1.ld_symbols -\
248 			((struct old_link_dynamic *)x)->v1.ld_stab :	\
249 			(x)->v2->ld_symbols - (x)->v2->ld_stab)
250 
251 #undef v2
252 #undef v1
253 
254 #endif /* !_link_h */
255 
256 #define	MAIN_BASE 0x2000	/* base address of a.out in 4.x system */
257 
258 /*
259  * Macros for getting to linker a.out format private data.
260  */
261 #define	AOUTPRV(X)	((X)->rt_priv)
262 #define	AOUTDYN(X)	(((Rt_aoutp *)(X)->rt_priv)->lm_ld)
263 #define	LM2LP(X)	((struct ld_private *)((Rt_aoutp *) \
264 				(X)->rt_priv)->lm_lpd)
265 #define	TEXTBASE(X)	(LM2LP(X)->lp_textbase)
266 
267 /*
268  * Most of the above macros are used from AOUT specific routines, however there
269  * are a couple of instances where we need to ensure the file being processed
270  * is AOUT before dereferencing the macro.
271  */
272 #define	THIS_IS_AOUT(X)		(FCT(X) == &aout_fct)
273 
274 /*
275  * Code collapsing macros.
276  */
277 #define	v2 ld_un.ld_2
278 #define	v1 ld_un.ld_1
279 #define	JMPOFF(x)	(x)->v2->ld_plt
280 #define	RELOCOFF(x)	(x)->v2->ld_rel
281 #define	HASHOFF(x)	(x)->v2->ld_hash
282 #define	SYMOFF(x)	(x)->v2->ld_stab
283 #define	STROFF(x)	(x)->v2->ld_symbols
284 
285 struct jbind {
286 	int	jb_inst[3];	/* need 4 instructions for jump slot */
287 };
288 
289 struct fshash {
290 	int	fssymbno;	/* ordinal symbol number */
291 	int	next;		/* index to the hash array pointed by fs_hash */
292 };
293 
294 /*
295  * Sparc relocation types.
296  */
297 enum reloc_type
298 {
299 	RELOC_8,	RELOC_16,	RELOC_32,	/* simplest relocs */
300 	RELOC_DISP8,	RELOC_DISP16,	RELOC_DISP32,	/* Disp's (pc-rel) */
301 	RELOC_WDISP30,	RELOC_WDISP22,			/* SR word disp's */
302 	RELOC_HI22,	RELOC_22,			/* SR 22-bit relocs */
303 	RELOC_13,	RELOC_LO10,			/* SR 13&10-bit reloc */
304 	RELOC_SFA_BASE,	RELOC_SFA_OFF13,		/* SR S.F.A. relocs */
305 	RELOC_BASE10,	RELOC_BASE13,	RELOC_BASE22,	/* base_relative pic */
306 	RELOC_PC10,	RELOC_PC22,			/* special pc-rel pic */
307 	RELOC_JMP_TBL,					/* jmp_tbl_rel in pic */
308 	RELOC_SEGOFF16,					/* Shlib off-in-seg */
309 	RELOC_GLOB_DAT, RELOC_JMP_SLOT, RELOC_RELATIVE	/* rtld relocs */
310 };
311 
312 /*
313  * Format of a relocation datum.
314  */
315 #define	r_symbolnum 	r_index
316 
317 struct	relocation_info		/* used when header.a_machtype == M_SPARC */
318 {
319 	ulong_t		r_address;	/* relocation addr (offset in seg) */
320 	uint_t 		r_index   :24;	/* segment index or symbol index */
321 	uint_t 		r_extern  : 1;	/* if F, r_index==SEG#; if T, SYM idx */
322 	int			  : 2;	/* <unused> */
323 	enum reloc_type r_type    : 5;	/* type of relocation to perform */
324 	long		r_addend;	/* addend for relocation value */
325 };
326 
327 struct ld_private {
328 	struct	jbind *lp_plt;		/* procedure linkage table */
329 	struct	relocation_info *lp_rp;	/* relocation table */
330 	struct	fshash *lp_hash;	/* hash table */
331 	struct	nlist *lp_symtab;	/* symbol table */
332 	char	*lp_symstr;		/* symbol strings */
333 	caddr_t	lp_textbase;		/* base address for text addressing */
334 	struct	nlist *(*lp_interp)();	/* link map interpreter */
335 	long	lp_refcnt;		/* reference count of link map */
336 	struct 	dl_object *lp_dlp;	/* pointer to a dlopen object */
337 	caddr_t	lp_symbol_base;		/* base address for symbols */
338 };
339 
340 
341 /*
342  * Offsets of various sections of an object file.
343  */
344 #define	PAGSIZ		0x02000
345 #define	SEGSIZ		PAGSIZ
346 
347 #define	N_TXTOFF(x) \
348 	/* text segment */ \
349 	((x).a_magic == ZMAGIC ? 0 : sizeof (struct exec))
350 
351 #define	N_SYMOFF(x) \
352 	/* symbol table */ \
353 	(N_TXTOFF(x) + (x).a_text + (x).a_data + (x).a_trsize + (x).a_drsize)
354 
355 #define	SIZE(x) \
356 	/* round to segment size */ \
357 	(M_SROUND((x).a_text) + (x).a_data + (x).a_bss)
358 
359 #ifdef	__cplusplus
360 }
361 #endif
362 
363 #endif	/* _A_DOT_OUT_DOT_H */
364