xref: /titanic_41/usr/src/cmd/sgs/rtld/common/_a.out.h (revision 16dd44c265271a75647fb0bb41109bb7c585a526)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 #ifndef	_A_DOT_OUT_DOT_H
27 #define	_A_DOT_OUT_DOT_H
28 
29 #include <sys/types.h>
30 #include <sys/mman.h>
31 #include <a.out.h>
32 #include <_rtld.h>
33 
34 #ifdef	__cplusplus
35 extern "C" {
36 #endif
37 
38 #define	max(a, b)	((a) < (b) ? (b) : (a))
39 
40 typedef struct link_dynamic	Link_dynamic;
41 
42 /*
43  * Extern functions for a.out format file class.
44  */
45 extern	ulong_t	aout_bndr(caddr_t);
46 extern	int	aout_get_mmap(Lm_list *, mmapobj_result_t *);
47 extern	Sym	*aout_lookup_sym(Slookup *, Rt_map **, uint_t *, int *);
48 extern	Rt_map	*aout_new_lmp(Lm_list *, Aliste, Fdesc *, Addr, size_t, void *,
49 		    int *);
50 extern	void	aout_plt_write(caddr_t, ulong_t);
51 extern	int	aout_reloc(Rt_map *, uint_t, int *, APlist **);
52 extern	void	aout_rtbndr(caddr_t);
53 extern	Fct	*aout_verify(caddr_t, size_t, Fdesc *, const char *,
54 		    Rej_desc *);
55 
56 /*
57  * Private data for an a.out format file class.
58  */
59 typedef struct _rt_aout_private {
60 	struct link_dynamic	*lm_ld;		/* 4.x aout dynamic pointer */
61 	struct ld_private	*lm_lpd;	/* private aout object area */
62 } Rt_aoutp;
63 
64 /*
65  * Special defines for a.out format file class.
66  */
67 #ifndef NULL
68 #define	NULL	0
69 #endif
70 #define	N_UNDF	0x0		/* undefined */
71 #define	N_ABS	0x2		/* absolute */
72 #define	N_COMM	0x12		/* common (internal to ld) */
73 #define	N_EXT	01		/* external bit, or'ed in */
74 
75 /*
76  * Format of a symbol table entry.
77  */
78 struct	nlist {
79 	union {
80 		char	*n_name;		/* for use when in-core */
81 		long	n_strx;		/* index into file string table */
82 	} n_un;
83 	uchar_t 	n_type;		/* type flag (N_TEXT,..)  */
84 	char		n_other;	/* unused */
85 	short		n_desc;		/* see <stab.h> */
86 	ulong_t		n_value;	/* value of symbol (or sdb offset) */
87 };
88 
89 /*
90  * Link editor public definitions.
91  */
92 
93 #ifndef _link_h
94 #define	_link_h
95 
96 /*
97  * Structure describing logical name and requirements on an object
98  * which is to be loaded dynamically.
99  */
100 struct old_link_object {
101 	char	*lo_name;		/* name of object */
102 	int	lo_library : 1,		/* searched for by library rules */
103 		lo_unused : 31;
104 	short	lo_major;		/* major version number */
105 	short	lo_minor;		/* minor version number */
106 };
107 
108 struct link_object {
109 	long	lo_name;		/* name (often relative) */
110 	int	lo_library : 1,		/* searched for by library rules */
111 		lo_unused : 31;
112 	short	lo_major;		/* major version number */
113 	short	lo_minor;		/* minor version number */
114 	long	lo_next;		/* next one (often relative) */
115 };
116 typedef	struct	link_object Lnk_obj;
117 
118 /*
119  * Structure describing name and placement of dynamically loaded
120  * objects in a process' address space.
121  */
122 typedef struct a_link_map	A_link_map;
123 
124 struct a_link_map {
125 	caddr_t	lm_addr;		/* address at which object mapped */
126 	char	*lm_name;		/* full name of loaded object */
127 	struct	a_link_map *lm_next;	/* next object in map */
128 	struct	link_object *lm_lop;	/* link object that got us here */
129 	caddr_t lm_lob;			/* base address for said link object */
130 	int	lm_rwt : 1;		/* text is read/write */
131 	struct	link_dynamic *lm_ld;	/* dynamic structure */
132 	caddr_t	lm_lpd;			/* loader private data */
133 };
134 
135 /*
136  * Version 1 of dynamic linking information.  With the exception of
137  * ld_loaded (determined at execution time) and ld_stab_hash (a special
138  * case of relocation handled at execution time), the values in this
139  * structure reflect offsets from the containing link_dynamic structure.
140  */
141 struct link_dynamic_1 {
142 	struct	a_link_map *ld_loaded;	/* list of loaded objects */
143 	long	ld_need;		/* list of needed objects */
144 	long	ld_rules;		/* search rules for library objects */
145 	long	ld_got;			/* global offset table */
146 	long	ld_plt;			/* procedure linkage table */
147 	long	ld_rel;			/* relocation table */
148 	long	ld_hash;		/* symbol hash table */
149 	long	ld_stab;		/* symbol table itself */
150 	long	(*ld_stab_hash)();	/* "pointer" to symbol hash function */
151 	long	ld_buckets;		/* number of hash buckets */
152 	long	ld_symbols;		/* symbol strings */
153 	long	ld_symb_size;		/* size of symbol strings */
154 	long	ld_text;		/* size of text area */
155 };
156 
157 struct link_dynamic_2 {
158 	struct	a_link_map *ld_loaded;	/* list of loaded objects */
159 	long	ld_need;		/* list of needed objects */
160 	long	ld_rules;		/* search rules for library objects */
161 	long	ld_got;			/* global offset table */
162 	long	ld_plt;			/* procedure linkage table */
163 	long	ld_rel;			/* relocation table */
164 	long	ld_hash;		/* symbol hash table */
165 	long	ld_stab;		/* symbol table itself */
166 	long	(*ld_stab_hash)();	/* "pointer" to symbol hash function */
167 	long	ld_buckets;		/* number of hash buckets */
168 	long	ld_symbols;		/* symbol strings */
169 	long	ld_symb_size;		/* size of symbol strings */
170 	long	ld_text;		/* size of text area */
171 	long	ld_plt_sz;		/* size of procedure linkage table */
172 };
173 
174 /*
175  * Structure pointing to run time allocated common symbols and
176  * its string.
177  */
178 struct rtc_symb {
179 	struct	nlist *rtc_sp;		/* symbol for common */
180 	struct	rtc_symb *rtc_next;	/* next common */
181 };
182 
183 /*
184  * Debugger interface structure.
185  */
186 struct 	ld_debug {
187 	int	ldd_version;		/* version # of interface */
188 	int	ldd_in_debugger;	/* a debugger is running us */
189 	int	ldd_sym_loaded;		/* we loaded some symbols */
190 	char    *ldd_bp_addr;		/* place for ld-generated bpt */
191 	int	ldd_bp_inst;		/* instruction which was there */
192 	struct rtc_symb *ldd_cp;	/* commons we built */
193 };
194 
195 /*
196  * Structure associated with each object which may be or which requires
197  * execution-time link editing.  Used by the run-time linkage editor to
198  * identify needed objects and symbol definitions and references.
199  */
200 struct 	old_link_dynamic {
201 	int	ld_version;		/* version # of this structure */
202 	union {
203 		struct link_dynamic_1 ld_1;
204 	} ld_un;
205 
206 	int	in_debugging;
207 	int	sym_loaded;
208 	char    *bp_addr;
209 	int	bp_inst;
210 	struct rtc_symb *cp; 		/* pointer to an array of runtime */
211 					/* allocated common symbols. */
212 };
213 
214 struct	link_dynamic {
215 	int	ld_version;		/* version # of this structure */
216 	struct 	ld_debug *ldd;
217 	union {
218 		struct link_dynamic_1 *ld_1;
219 		struct link_dynamic_2 *ld_2;
220 	} ld_un;
221 };
222 
223 
224 /*
225  * Get size of relocations.
226  */
227 #define	GETGOTSZ(x)	(x->ld_version < 2 ?				\
228 			((struct old_link_dynamic *)x)->v1.ld_plt -	\
229 			((struct old_link_dynamic *)x)->v1.ld_got :	\
230 			(x)->v2->ld_plt - (x)->v2->ld_got)
231 
232 #define	GETPLTSZ(x)	(x->ld_version < 2 ?				\
233 			((struct old_link_dynamic *)x)->v1.ld_rel -	\
234 			((struct old_link_dynamic *)x)->v1.ld_plt :	\
235 			(x)->v2->ld_rel - (x)->v2->ld_plt)
236 
237 #define	GETRELSZ(x)	(x->ld_version < 2 ?				\
238 			((struct old_link_dynamic *)x)->v1.ld_hash -	\
239 			((struct old_link_dynamic *)x)->v1.ld_rel :	\
240 			(x)->v2->ld_hash - (x)->v2->ld_rel)
241 
242 #define	GETHASHSZ(x)	(x->ld_version < 2 ?				\
243 			((struct old_link_dynamic *)x)->v1.ld_stab -	\
244 			((struct old_link_dynamic *)x)->v1.ld_hash :	\
245 			(x)->v2->ld_stab - (x)->v2->ld_hash)
246 
247 #define	GETSTABSZ(x)	(x->ld_version < 2 ?				\
248 			((struct old_link_dynamic *)x)->v1.ld_symbols -\
249 			((struct old_link_dynamic *)x)->v1.ld_stab :	\
250 			(x)->v2->ld_symbols - (x)->v2->ld_stab)
251 
252 #undef v2
253 #undef v1
254 
255 #endif /* !_link_h */
256 
257 #define	MAIN_BASE 0x2000	/* base address of a.out in 4.x system */
258 
259 /*
260  * Macros for getting to linker a.out format private data.
261  */
262 #define	AOUTPRV(X)	((X)->rt_priv)
263 #define	AOUTDYN(X)	(((Rt_aoutp *)(X)->rt_priv)->lm_ld)
264 #define	LM2LP(X)	((struct ld_private *)((Rt_aoutp *) \
265 				(X)->rt_priv)->lm_lpd)
266 #define	TEXTBASE(X)	(LM2LP(X)->lp_textbase)
267 
268 /*
269  * Most of the above macros are used from AOUT specific routines, however there
270  * are a couple of instances where we need to ensure the file being processed
271  * is AOUT before dereferencing the macro.
272  */
273 #define	THIS_IS_AOUT(X)		(FCT(X) == &aout_fct)
274 
275 /*
276  * Code collapsing macros.
277  */
278 #define	v2 ld_un.ld_2
279 #define	v1 ld_un.ld_1
280 #define	JMPOFF(x)	(x)->v2->ld_plt
281 #define	RELOCOFF(x)	(x)->v2->ld_rel
282 #define	HASHOFF(x)	(x)->v2->ld_hash
283 #define	SYMOFF(x)	(x)->v2->ld_stab
284 #define	STROFF(x)	(x)->v2->ld_symbols
285 
286 struct jbind {
287 	int	jb_inst[3];	/* need 4 instructions for jump slot */
288 };
289 
290 struct fshash {
291 	int	fssymbno;	/* ordinal symbol number */
292 	int	next;		/* index to the hash array pointed by fs_hash */
293 };
294 
295 /*
296  * Sparc relocation types.
297  */
298 enum reloc_type
299 {
300 	RELOC_8,	RELOC_16,	RELOC_32,	/* simplest relocs */
301 	RELOC_DISP8,	RELOC_DISP16,	RELOC_DISP32,	/* Disp's (pc-rel) */
302 	RELOC_WDISP30,	RELOC_WDISP22,			/* SR word disp's */
303 	RELOC_HI22,	RELOC_22,			/* SR 22-bit relocs */
304 	RELOC_13,	RELOC_LO10,			/* SR 13&10-bit reloc */
305 	RELOC_SFA_BASE,	RELOC_SFA_OFF13,		/* SR S.F.A. relocs */
306 	RELOC_BASE10,	RELOC_BASE13,	RELOC_BASE22,	/* base_relative pic */
307 	RELOC_PC10,	RELOC_PC22,			/* special pc-rel pic */
308 	RELOC_JMP_TBL,					/* jmp_tbl_rel in pic */
309 	RELOC_SEGOFF16,					/* Shlib off-in-seg */
310 	RELOC_GLOB_DAT, RELOC_JMP_SLOT, RELOC_RELATIVE	/* rtld relocs */
311 };
312 
313 /*
314  * Format of a relocation datum.
315  */
316 #define	r_symbolnum 	r_index
317 
318 struct	relocation_info		/* used when header.a_machtype == M_SPARC */
319 {
320 	ulong_t		r_address;	/* relocation addr (offset in seg) */
321 	uint_t 		r_index   :24;	/* segment index or symbol index */
322 	uint_t 		r_extern  : 1;	/* if F, r_index==SEG#; if T, SYM idx */
323 	int			  : 2;	/* <unused> */
324 	enum reloc_type r_type    : 5;	/* type of relocation to perform */
325 	long		r_addend;	/* addend for relocation value */
326 };
327 
328 struct ld_private {
329 	struct	jbind *lp_plt;		/* procedure linkage table */
330 	struct	relocation_info *lp_rp;	/* relocation table */
331 	struct	fshash *lp_hash;	/* hash table */
332 	struct	nlist *lp_symtab;	/* symbol table */
333 	char	*lp_symstr;		/* symbol strings */
334 	caddr_t	lp_textbase;		/* base address for text addressing */
335 	struct	nlist *(*lp_interp)();	/* link map interpreter */
336 	long	lp_refcnt;		/* reference count of link map */
337 	struct 	dl_object *lp_dlp;	/* pointer to a dlopen object */
338 	caddr_t	lp_symbol_base;		/* base address for symbols */
339 };
340 
341 
342 /*
343  * Offsets of various sections of an object file.
344  */
345 #define	PAGSIZ		0x02000
346 #define	SEGSIZ		PAGSIZ
347 
348 #define	N_TXTOFF(x) \
349 	/* text segment */ \
350 	((x).a_magic == ZMAGIC ? 0 : sizeof (struct exec))
351 
352 #define	N_SYMOFF(x) \
353 	/* symbol table */ \
354 	(N_TXTOFF(x) + (x).a_text + (x).a_data + (x).a_trsize + (x).a_drsize)
355 
356 #define	SIZE(x) \
357 	/* round to segment size */ \
358 	(M_SROUND((x).a_text) + (x).a_data + (x).a_bss)
359 
360 #ifdef	__cplusplus
361 }
362 #endif
363 
364 #endif	/* _A_DOT_OUT_DOT_H */
365