xref: /illumos-gate/usr/src/cmd/sgs/libelf/common/clscook.c (revision e7cbe64f7a72dae5cb44f100db60ca88f3313c65)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*	Copyright (c) 1988 AT&T	*/
23 /*	  All Rights Reserved  	*/
24 
25 
26 /*
27  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
28  * Use is subject to license terms.
29  */
30 
31 #pragma ident	"%Z%%M%	%I%	%E% SMI"
32 
33 /*
34  * This stuff used to live in cook.c, but was moved out to
35  * facilitate dual (Elf32 and Elf64) compilation.  See block
36  * comment in cook.c for more info.
37  */
38 
39 
40 #include "syn.h"
41 #include <string.h>
42 #include <ar.h>
43 #include <stdlib.h>
44 #include <errno.h>
45 #include "decl.h"
46 #include "member.h"
47 #include "msg.h"
48 
49 /*
50  * This module is compiled twice, the second time having
51  * -D_ELF64 defined.  The following set of macros, along
52  * with machelf.h, represent the differences between the
53  * two compilations.  Be careful *not* to add any class-
54  * dependent code (anything that has elf32 or elf64 in the
55  * name) to this code without hiding it behind a switch-
56  * able macro like these.
57  */
58 #if	defined(_ELF64)
59 #define	Snode		Snode64
60 #define	ELFCLASS	ELFCLASS64
61 #define	ElfField	Elf64
62 #define	_elf_snode_init	_elf64_snode_init
63 #define	_elf_prepscan	_elf64_prepscan
64 #define	_elf_cookscn	_elf64_cookscn
65 #define	_elf_mtype	_elf64_mtype
66 #define	_elf_msize	_elf64_msize
67 #define	elf_fsize	elf64_fsize
68 #define	_elf_snode	_elf64_snode
69 #define	_elf_ehdr	_elf64_ehdr
70 #define	elf_xlatetom	elf64_xlatetom
71 #define	_elf_phdr	_elf64_phdr
72 #define	_elf_shdr	_elf64_shdr
73 #define	_elf_prepscn	_elf64_prepscn
74 
75 #else  /* Elf32 */
76 #define	Snode		Snode32
77 #define	ELFCLASS	ELFCLASS32
78 #define	ElfField	Elf32
79 #define	_elf_snode_init	_elf32_snode_init
80 #define	_elf_prepscan	_elf32_prepscan
81 #define	_elf_cookscn	_elf32_cookscn
82 #define	_elf_mtype	_elf32_mtype
83 #define	_elf_msize	_elf32_msize
84 #define	elf_fsize	elf32_fsize
85 #define	_elf_snode	_elf32_snode
86 #define	_elf_ehdr	_elf32_ehdr
87 #define	elf_xlatetom	elf32_xlatetom
88 #define	_elf_phdr	_elf32_phdr
89 #define	_elf_shdr	_elf32_shdr
90 #define	_elf_prepscn	_elf32_prepscn
91 
92 #endif /* _ELF64 */
93 
94 
95 static Okay
96 _elf_prepscn(Elf *elf, size_t cnt)
97 {
98 	NOTE(ASSUMING_PROTECTED(*elf))
99 	Elf_Scn *	s;
100 	Elf_Scn *	end;
101 
102 	if (cnt == 0)
103 		return (OK_YES);
104 
105 	if ((s = malloc(cnt * sizeof (Elf_Scn))) == 0) {
106 		_elf_seterr(EMEM_SCN, errno);
107 		return (OK_NO);
108 	}
109 	NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*s))
110 	elf->ed_scntabsz = cnt;
111 	end = s + cnt;
112 	elf->ed_hdscn = s;
113 	do {
114 		*s = _elf_snode_init.sb_scn;
115 		s->s_elf = elf;
116 		s->s_next = s + 1;
117 		s->s_index = s - elf->ed_hdscn;
118 		s->s_shdr = (Shdr*)s->s_elf->ed_shdr + s->s_index;
119 		ELFMUTEXINIT(&s->s_mutex);
120 
121 		/*
122 		 * Section has not yet been cooked!
123 		 *
124 		 * We don't cook a section until it's data is actually
125 		 * referenced.
126 		 */
127 		s->s_myflags = 0;
128 	} while (++s < end);
129 
130 	elf->ed_tlscn = --s;
131 	s->s_next = 0;
132 
133 	/*
134 	 * Section index SHN_UNDEF (0) does not and cannot
135 	 * have a data buffer.  Fix it here.  Also mark the
136 	 * initial section as being allocated for the block
137 	 */
138 
139 	s = elf->ed_hdscn;
140 	s->s_myflags = SF_ALLOC;
141 	s->s_hdnode = 0;
142 	s->s_tlnode = 0;
143 	NOTE(NOW_VISIBLE_TO_OTHER_THREADS(*s))
144 	return (OK_YES);
145 }
146 
147 
148 Okay
149 _elf_cookscn(Elf_Scn * s)
150 {
151 	NOTE(ASSUMING_PROTECTED(*s, *(s->s_elf)))
152 	Elf *			elf;
153 	Shdr *			sh;
154 	register Dnode *	d = &s->s_dnode;
155 	size_t			fsz, msz;
156 	unsigned		work;
157 
158 	NOTE(NOW_INVISIBLE_TO_OTHER_THREADS(*d))
159 	s->s_hdnode = s->s_tlnode = d;
160 	s->s_err = 0;
161 	s->s_shflags = 0;
162 	s->s_uflags = 0;
163 
164 
165 	/*
166 	 * Prepare d_data for inspection, but don't actually
167 	 * translate data until needed.  Leave the READY
168 	 * flag off.  NOBITS sections see zero size.
169 	 */
170 	elf = s->s_elf;
171 	sh = s->s_shdr;
172 
173 	d->db_scn = s;
174 	d->db_off = sh->sh_offset;
175 	d->db_data.d_align = sh->sh_addralign;
176 	d->db_data.d_version = elf->ed_version;
177 	ELFACCESSDATA(work, _elf_work)
178 	d->db_data.d_type = _elf_mtype(elf, sh->sh_type, work);
179 	d->db_data.d_buf = 0;
180 	d->db_data.d_off = 0;
181 	fsz = elf_fsize(d->db_data.d_type, 1, elf->ed_version);
182 	msz = _elf_msize(d->db_data.d_type, elf->ed_version);
183 	d->db_data.d_size = (sh->sh_size / fsz) * msz;
184 	d->db_shsz = sh->sh_size;
185 	d->db_raw = 0;
186 	d->db_buf = 0;
187 	d->db_uflags = 0;
188 	d->db_myflags = 0;
189 	d->db_next = 0;
190 
191 	if (sh->sh_type != SHT_NOBITS)
192 		d->db_fsz = sh->sh_size;
193 	else
194 		d->db_fsz = 0;
195 
196 	s->s_myflags |= SF_READY;
197 
198 	NOTE(NOW_VISIBLE_TO_OTHER_THREADS(*d))
199 	return (OK_YES);
200 }
201 
202 
203 
204 Snode *
205 _elf_snode()
206 {
207 	register Snode	*s;
208 
209 	if ((s = malloc(sizeof (Snode))) == 0) {
210 		_elf_seterr(EMEM_SNODE, errno);
211 		return (0);
212 	}
213 	*s = _elf_snode_init;
214 	ELFMUTEXINIT(&s->sb_scn.s_mutex);
215 	s->sb_scn.s_myflags = SF_ALLOC | SF_READY;
216 	s->sb_scn.s_shdr = &s->sb_shdr;
217 	return (s);
218 }
219 
220 
221 
222 int
223 _elf_ehdr(Elf * elf, int inplace)
224 {
225 	NOTE(ASSUMING_PROTECTED(*elf))
226 	register size_t	fsz;		/* field size */
227 	Elf_Data	dst, src;
228 
229 	fsz = elf_fsize(ELF_T_EHDR, 1, elf->ed_version);
230 	if (fsz > elf->ed_fsz) {
231 		_elf_seterr(EFMT_EHDRSZ, 0);
232 		return (-1);
233 	}
234 	if (inplace && (fsz >= sizeof (Ehdr))) {
235 		/*
236 		 * The translated Ehdr will fit over the original Ehdr.
237 		 */
238 		/* LINTED */
239 		elf->ed_ehdr = (Ehdr *)elf->ed_ident;
240 		elf->ed_status = ES_COOKED;
241 	} else {
242 		elf->ed_ehdr = malloc(sizeof (Ehdr));
243 		if (elf->ed_ehdr == 0) {
244 			_elf_seterr(EMEM_EHDR, errno);
245 			return (-1);
246 		}
247 		elf->ed_myflags |= EDF_EHALLOC;
248 	}
249 
250 	/*
251 	 * Memory size >= fsz, because otherwise the memory version
252 	 * loses information and cannot accurately implement the
253 	 * file.
254 	 */
255 
256 	src.d_buf = (Elf_Void *)elf->ed_ident;
257 	src.d_type = ELF_T_EHDR;
258 	src.d_size = fsz;
259 	src.d_version = elf->ed_version;
260 	dst.d_buf = (Elf_Void *)elf->ed_ehdr;
261 	dst.d_size = sizeof (Ehdr);
262 	dst.d_version = EV_CURRENT;
263 
264 	if ((_elf_vm(elf, (size_t)0, fsz) != OK_YES) ||
265 	    (elf_xlatetom(&dst, &src, elf->ed_encode) == 0)) {
266 		if (elf->ed_myflags & EDF_EHALLOC) {
267 			elf->ed_myflags &= ~EDF_EHALLOC;
268 			free(elf->ed_ehdr);
269 		}
270 		elf->ed_ehdr = 0;
271 		return (-1);
272 	}
273 
274 	if (((Ehdr*)elf->ed_ehdr)->e_ident[EI_CLASS] != ELFCLASS) {
275 		_elf_seterr(EREQ_CLASS, 0);
276 		if (elf->ed_myflags & EDF_EHALLOC) {
277 			elf->ed_myflags &= ~EDF_EHALLOC;
278 			free(elf->ed_ehdr);
279 		}
280 		elf->ed_ehdr = 0;
281 		return (-1);
282 	}
283 
284 	if (((Ehdr*)elf->ed_ehdr)->e_version != elf->ed_version) {
285 		_elf_seterr(EFMT_VER2, 0);
286 		if (elf->ed_myflags & EDF_EHALLOC) {
287 			elf->ed_myflags &= ~EDF_EHALLOC;
288 			free(elf->ed_ehdr);
289 		}
290 		elf->ed_ehdr = 0;
291 		return (-1);
292 	}
293 
294 	return (0);
295 }
296 
297 
298 
299 int
300 _elf_phdr(Elf * elf, int inplace)
301 {
302 	NOTE(ASSUMING_PROTECTED(*elf))
303 	register size_t		fsz, msz;
304 	Elf_Data		dst, src;
305 	Ehdr *			eh = elf->ed_ehdr;	/* must be present */
306 	unsigned		work;
307 
308 	if (eh->e_phnum == 0)
309 		return (0);
310 
311 	fsz = elf_fsize(ELF_T_PHDR, 1, elf->ed_version);
312 	if (eh->e_phentsize != fsz) {
313 		_elf_seterr(EFMT_PHDRSZ, 0);
314 		return (-1);
315 	}
316 
317 	fsz *= eh->e_phnum;
318 	ELFACCESSDATA(work, _elf_work)
319 	msz = _elf_msize(ELF_T_PHDR, work) * eh->e_phnum;
320 	if ((eh->e_phoff == 0) ||
321 	    ((fsz + eh->e_phoff) > elf->ed_fsz)) {
322 		_elf_seterr(EFMT_PHTAB, 0);
323 		return (-1);
324 	}
325 
326 	if (inplace && fsz >= msz && eh->e_phoff % sizeof (ElfField) == 0) {
327 		elf->ed_phdr = (Elf_Void *)(elf->ed_ident + eh->e_phoff);
328 		elf->ed_status = ES_COOKED;
329 	} else {
330 		if ((elf->ed_phdr = malloc(msz)) == 0) {
331 			_elf_seterr(EMEM_PHDR, errno);
332 			return (-1);
333 		}
334 		elf->ed_myflags |= EDF_PHALLOC;
335 	}
336 	src.d_buf = (Elf_Void *)(elf->ed_ident + eh->e_phoff);
337 	src.d_type = ELF_T_PHDR;
338 	src.d_size = fsz;
339 	src.d_version = elf->ed_version;
340 	dst.d_buf = elf->ed_phdr;
341 	dst.d_size = msz;
342 	dst.d_version = work;
343 	if ((_elf_vm(elf, (size_t)eh->e_phoff, fsz) != OK_YES) ||
344 	    (elf_xlatetom(&dst, &src, elf->ed_encode) == 0)) {
345 		if (elf->ed_myflags & EDF_PHALLOC) {
346 			elf->ed_myflags &= ~EDF_PHALLOC;
347 			free(elf->ed_phdr);
348 		}
349 		elf->ed_phdr = 0;
350 		return (-1);
351 	}
352 	elf->ed_phdrsz = msz;
353 	return (0);
354 }
355 
356 
357 
358 int
359 _elf_shdr(Elf * elf, int inplace)
360 {
361 	NOTE(ASSUMING_PROTECTED(*elf))
362 	register size_t		fsz, msz;
363 	size_t			scncnt;
364 	Elf_Data		dst, src;
365 	register Ehdr		*eh = elf->ed_ehdr;	/* must be present */
366 
367 	if ((eh->e_shnum == 0) && (eh->e_shoff == 0))
368 		return (0);
369 
370 	fsz = elf_fsize(ELF_T_SHDR, 1, elf->ed_version);
371 	if (eh->e_shentsize != fsz) {
372 		_elf_seterr(EFMT_SHDRSZ, 0);
373 		return (-1);
374 	}
375 	/*
376 	 * If we are dealing with a file with 'extended section
377 	 * indexes' - then we need to load the first section
378 	 * header.  The actual section count is stored in
379 	 * Shdr[0].sh_size.
380 	 */
381 	if ((scncnt = eh->e_shnum) == 0) {
382 		Shdr	sh;
383 		if ((eh->e_shoff == 0) ||
384 		    (elf->ed_fsz <= eh->e_shoff) ||
385 		    (elf->ed_fsz - eh->e_shoff < fsz)) {
386 			_elf_seterr(EFMT_SHTAB, 0);
387 			return (-1);
388 		}
389 		src.d_buf = (Elf_Void *)(elf->ed_ident + eh->e_shoff);
390 		src.d_type = ELF_T_SHDR;
391 		src.d_size = fsz;
392 		src.d_version = elf->ed_version;
393 		dst.d_buf = (Elf_Void *)&sh;
394 		dst.d_size = sizeof (Shdr);
395 		dst.d_version = EV_CURRENT;
396 		if ((_elf_vm(elf, (size_t)eh->e_shoff, fsz) != OK_YES) ||
397 		    (elf_xlatetom(&dst, &src, elf->ed_encode) == 0)) {
398 			return (-1);
399 		}
400 		scncnt = sh.sh_size;
401 	}
402 
403 	fsz *= scncnt;
404 	msz = scncnt * sizeof (Shdr);
405 	if ((eh->e_shoff == 0) ||
406 	    (elf->ed_fsz <= eh->e_shoff) ||
407 	    (elf->ed_fsz - eh->e_shoff < fsz)) {
408 		_elf_seterr(EFMT_SHTAB, 0);
409 		return (-1);
410 	}
411 
412 	if (inplace && (fsz >= msz) &&
413 	    ((eh->e_shoff % sizeof (ElfField)) == 0)) {
414 		/* LINTED */
415 		elf->ed_shdr = (Shdr *)(elf->ed_ident + eh->e_shoff);
416 		elf->ed_status = ES_COOKED;
417 	} else {
418 		if ((elf->ed_shdr = malloc(msz)) == 0) {
419 			_elf_seterr(EMEM_SHDR, errno);
420 			return (-1);
421 		}
422 		elf->ed_myflags |= EDF_SHALLOC;
423 	}
424 	src.d_buf = (Elf_Void *)(elf->ed_ident + eh->e_shoff);
425 	src.d_type = ELF_T_SHDR;
426 	src.d_size = fsz;
427 	src.d_version = elf->ed_version;
428 	dst.d_buf = (Elf_Void *)elf->ed_shdr;
429 	dst.d_size = msz;
430 	dst.d_version = EV_CURRENT;
431 	if ((_elf_vm(elf, (size_t)eh->e_shoff, fsz) != OK_YES) ||
432 	    (elf_xlatetom(&dst, &src, elf->ed_encode) == 0) ||
433 	    (_elf_prepscn(elf, scncnt) != OK_YES)) {
434 		if (elf->ed_myflags & EDF_SHALLOC) {
435 			elf->ed_myflags &= ~EDF_SHALLOC;
436 			free(elf->ed_shdr);
437 		}
438 		elf->ed_shdr = 0;
439 		return (-1);
440 	}
441 	return (0);
442 }
443