1/*-
2 * Copyright (c) 1998-2000 Doug Rabson
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/kern/link_elf.c 192859 2009-05-26 21:39:09Z sson $");
29
30#include "opt_ddb.h"
31#include "opt_gdb.h"
32#include "opt_mac.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#ifdef GPROF
37#include <sys/gmon.h>
38#endif
39#include <sys/kernel.h>
40#include <sys/lock.h>
41#include <sys/malloc.h>
42#include <sys/mutex.h>
43#include <sys/mount.h>
44#include <sys/proc.h>
45#include <sys/namei.h>
46#include <sys/fcntl.h>
47#include <sys/vnode.h>
48#include <sys/linker.h>
49
50#include <machine/elf.h>
51
52#include <security/mac/mac_framework.h>
53
54#include <vm/vm.h>
55#include <vm/vm_param.h>
56#ifdef SPARSE_MAPPING
57#include <vm/vm_object.h>
58#include <vm/vm_kern.h>
59#include <vm/vm_extern.h>
60#endif
61#include <vm/pmap.h>
62#include <vm/vm_map.h>
63
64#include <sys/link_elf.h>
65
66#ifdef DDB_CTF
67#include <net/zlib.h>
68#endif
69
70#include "linker_if.h"
71
72#define MAXSEGS 4
73
74typedef struct elf_file {
75 struct linker_file lf; /* Common fields */
76 int preloaded; /* Was file pre-loaded */
77 caddr_t address; /* Relocation address */
78#ifdef SPARSE_MAPPING
79 vm_object_t object; /* VM object to hold file pages */
80#endif
81 Elf_Dyn* dynamic; /* Symbol table etc. */
82 Elf_Hashelt nbuckets; /* DT_HASH info */
83 Elf_Hashelt nchains;
84 const Elf_Hashelt* buckets;
85 const Elf_Hashelt* chains;
86 caddr_t hash;
87 caddr_t strtab; /* DT_STRTAB */
88 int strsz; /* DT_STRSZ */
89 const Elf_Sym* symtab; /* DT_SYMTAB */
90 Elf_Addr* got; /* DT_PLTGOT */
91 const Elf_Rel* pltrel; /* DT_JMPREL */
92 int pltrelsize; /* DT_PLTRELSZ */
93 const Elf_Rela* pltrela; /* DT_JMPREL */
94 int pltrelasize; /* DT_PLTRELSZ */
95 const Elf_Rel* rel; /* DT_REL */
96 int relsize; /* DT_RELSZ */
97 const Elf_Rela* rela; /* DT_RELA */
98 int relasize; /* DT_RELASZ */
99 caddr_t modptr;
100 const Elf_Sym* ddbsymtab; /* The symbol table we are using */
101 long ddbsymcnt; /* Number of symbols */
102 caddr_t ddbstrtab; /* String table */
103 long ddbstrcnt; /* number of bytes in string table */
104 caddr_t symbase; /* malloc'ed symbold base */
105 caddr_t strbase; /* malloc'ed string base */
106 caddr_t ctftab; /* CTF table */
107 long ctfcnt; /* number of bytes in CTF table */
108 caddr_t ctfoff; /* CTF offset table */
109 caddr_t typoff; /* Type offset table */
110 long typlen; /* Number of type entries. */
111#ifdef GDB
112 struct link_map gdb; /* hooks for gdb */
113#endif
114} *elf_file_t;
115
116#include <kern/kern_ctf.c>
117
118static int link_elf_link_common_finish(linker_file_t);
119static int link_elf_link_preload(linker_class_t cls,
120 const char*, linker_file_t*);
121static int link_elf_link_preload_finish(linker_file_t);
122static int link_elf_load_file(linker_class_t, const char*, linker_file_t*);
123static int link_elf_lookup_symbol(linker_file_t, const char*,
124 c_linker_sym_t*);
125static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t*);
126static int link_elf_search_symbol(linker_file_t, caddr_t value,
127 c_linker_sym_t* sym, long* diffp);
128
129static void link_elf_unload_file(linker_file_t);
130static void link_elf_unload_preload(linker_file_t);
131static int link_elf_lookup_set(linker_file_t, const char *,
132 void ***, void ***, int *);
133static int link_elf_each_function_name(linker_file_t,
134 int (*)(const char *, void *),
135 void *);
136static int link_elf_each_function_nameval(linker_file_t,
137 linker_function_nameval_callback_t,
138 void *);
139static void link_elf_reloc_local(linker_file_t);
140static long link_elf_symtab_get(linker_file_t, const Elf_Sym **);
141static long link_elf_strtab_get(linker_file_t, caddr_t *);
142static Elf_Addr elf_lookup(linker_file_t lf, Elf_Size symidx, int deps);
143
144static kobj_method_t link_elf_methods[] = {
145 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol),
146 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values),
147 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol),
148 KOBJMETHOD(linker_unload, link_elf_unload_file),
149 KOBJMETHOD(linker_load_file, link_elf_load_file),
150 KOBJMETHOD(linker_link_preload, link_elf_link_preload),
151 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish),
152 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set),
153 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name),
154 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval),
155 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get),
156 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get),
157 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get),
158 { 0, 0 }
159};
160
161static struct linker_class link_elf_class = {
162#if ELF_TARG_CLASS == ELFCLASS32
163 "elf32",
164#else
165 "elf64",
166#endif
167 link_elf_methods, sizeof(struct elf_file)
168};
169
170static int parse_dynamic(elf_file_t ef);
171static int relocate_file(elf_file_t ef);
172static int link_elf_preload_parse_symbols(elf_file_t ef);
173
174#ifdef GDB
175static void r_debug_state(struct r_debug *dummy_one,
176 struct link_map *dummy_two);
177
178/*
179 * A list of loaded modules for GDB to use for loading symbols.
180 */
181struct r_debug r_debug;
182
183#define GDB_STATE(s) r_debug.r_state = s; r_debug_state(NULL, NULL);
184
185/*
186 * Function for the debugger to set a breakpoint on to gain control.
187 */
188static void
189r_debug_state(struct r_debug *dummy_one __unused,
190 struct link_map *dummy_two __unused)
191{
192}
193
194static void
195link_elf_add_gdb(struct link_map *l)
196{
197 struct link_map *prev;
198
199 l->l_next = NULL;
200
201 if (r_debug.r_map == NULL) {
202 /* Add first. */
203 l->l_prev = NULL;
204 r_debug.r_map = l;
205 } else {
206 /* Append to list. */
207 for (prev = r_debug.r_map; prev->l_next != NULL; prev = prev->l_next)
208 ;
209 l->l_prev = prev;
210 prev->l_next = l;
211 }
212}
213
214static void
215link_elf_delete_gdb(struct link_map *l)
216{
217 if (l->l_prev == NULL) {
218 /* Remove first. */
219 if ((r_debug.r_map = l->l_next) != NULL)
220 l->l_next->l_prev = NULL;
221 } else {
222 /* Remove any but first. */
223 if ((l->l_prev->l_next = l->l_next) != NULL)
224 l->l_next->l_prev = l->l_prev;
225 }
226}
227#endif /* GDB */
228
229#ifdef __ia64__
230Elf_Addr link_elf_get_gp(linker_file_t);
231#endif
232
233/*
234 * The kernel symbol table starts here.
235 */
236extern struct _dynamic _DYNAMIC;
237
238static void
239link_elf_error(const char *filename, const char *s)
240{
241 if (filename == NULL)
242 printf("kldload: %s\n", s);
243 else
244 printf("kldload: %s: %s\n", filename, s);
245}
246
247/*
248 * Actions performed after linking/loading both the preloaded kernel and any
249 * modules; whether preloaded or dynamicly loaded.
250 */
251static int
252link_elf_link_common_finish(linker_file_t lf)
253{
254#ifdef GDB
255 elf_file_t ef = (elf_file_t)lf;
256 char *newfilename;
257#endif
258 int error;
259
260 /* Notify MD code that a module is being loaded. */
261 error = elf_cpu_load_file(lf);
262 if (error)
263 return (error);
264
265#ifdef GDB
266 GDB_STATE(RT_ADD);
267 ef->gdb.l_addr = lf->address;
268 newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK);
269 strcpy(newfilename, lf->filename);
270 ef->gdb.l_name = newfilename;
271 ef->gdb.l_ld = ef->dynamic;
272 link_elf_add_gdb(&ef->gdb);
273 GDB_STATE(RT_CONSISTENT);
274#endif
275
276 return (0);
277}
278
279static void
280link_elf_init(void* arg)
281{
282 Elf_Dyn *dp;
283 caddr_t modptr, baseptr, sizeptr;
284 elf_file_t ef;
285 char *modname;
286
287 linker_add_class(&link_elf_class);
288
289 dp = (Elf_Dyn*) &_DYNAMIC;
290 modname = NULL;
291 modptr = preload_search_by_type("elf" __XSTRING(__ELF_WORD_SIZE) " kernel");
292 if (modptr == NULL)
293 modptr = preload_search_by_type("elf kernel");
294 if (modptr)
295 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
296 if (modname == NULL)
297 modname = "kernel";
298 linker_kernel_file = linker_make_file(modname, &link_elf_class);
299 if (linker_kernel_file == NULL)
300 panic("link_elf_init: Can't create linker structures for kernel");
301
302 ef = (elf_file_t) linker_kernel_file;
303 ef->preloaded = 1;
304 ef->address = 0;
305#ifdef SPARSE_MAPPING
306 ef->object = 0;
307#endif
308 ef->dynamic = dp;
309
310 if (dp)
311 parse_dynamic(ef);
312 linker_kernel_file->address = (caddr_t) KERNBASE;
313 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
314
315 if (modptr) {
316 ef->modptr = modptr;
317 baseptr = preload_search_info(modptr, MODINFO_ADDR);
318 if (baseptr)
319 linker_kernel_file->address = *(caddr_t *)baseptr;
320 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
321 if (sizeptr)
322 linker_kernel_file->size = *(size_t *)sizeptr;
323 }
324 (void)link_elf_preload_parse_symbols(ef);
325
326#ifdef GDB
327 r_debug.r_map = NULL;
328 r_debug.r_brk = r_debug_state;
329 r_debug.r_state = RT_CONSISTENT;
330#endif
331
332 (void)link_elf_link_common_finish(linker_kernel_file);
333 linker_kernel_file->flags |= LINKER_FILE_LINKED;
334}
335
336SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, 0);
337
338static int
339link_elf_preload_parse_symbols(elf_file_t ef)
340{
341 caddr_t pointer;
342 caddr_t ssym, esym, base;
343 caddr_t strtab;
344 int strcnt;
345 Elf_Sym* symtab;
346 int symcnt;
347
348 if (ef->modptr == NULL)
349 return 0;
350 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_SSYM);
351 if (pointer == NULL)
352 return 0;
353 ssym = *(caddr_t *)pointer;
354 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_ESYM);
355 if (pointer == NULL)
356 return 0;
357 esym = *(caddr_t *)pointer;
358
359 base = ssym;
360
361 symcnt = *(long *)base;
362 base += sizeof(long);
363 symtab = (Elf_Sym *)base;
364 base += roundup(symcnt, sizeof(long));
365
366 if (base > esym || base < ssym) {
367 printf("Symbols are corrupt!\n");
368 return EINVAL;
369 }
370
371 strcnt = *(long *)base;
372 base += sizeof(long);
373 strtab = base;
374 base += roundup(strcnt, sizeof(long));
375
376 if (base > esym || base < ssym) {
377 printf("Symbols are corrupt!\n");
378 return EINVAL;
379 }
380
381 ef->ddbsymtab = symtab;
382 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
383 ef->ddbstrtab = strtab;
384 ef->ddbstrcnt = strcnt;
385
386 return 0;
387}
388
389static int
390parse_dynamic(elf_file_t ef)
391{
392 Elf_Dyn *dp;
393 int plttype = DT_REL;
394
395 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
396 switch (dp->d_tag) {
397 case DT_HASH:
398 {
399 /* From src/libexec/rtld-elf/rtld.c */
400 const Elf_Hashelt *hashtab = (const Elf_Hashelt *)
401 (ef->address + dp->d_un.d_ptr);
402 ef->nbuckets = hashtab[0];
403 ef->nchains = hashtab[1];
404 ef->buckets = hashtab + 2;
405 ef->chains = ef->buckets + ef->nbuckets;
406 break;
407 }
408 case DT_STRTAB:
409 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
410 break;
411 case DT_STRSZ:
412 ef->strsz = dp->d_un.d_val;
413 break;
414 case DT_SYMTAB:
415 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
416 break;
417 case DT_SYMENT:
418 if (dp->d_un.d_val != sizeof(Elf_Sym))
419 return ENOEXEC;
420 break;
421 case DT_PLTGOT:
422 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
423 break;
424 case DT_REL:
425 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
426 break;
427 case DT_RELSZ:
428 ef->relsize = dp->d_un.d_val;
429 break;
430 case DT_RELENT:
431 if (dp->d_un.d_val != sizeof(Elf_Rel))
432 return ENOEXEC;
433 break;
434 case DT_JMPREL:
435 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
436 break;
437 case DT_PLTRELSZ:
438 ef->pltrelsize = dp->d_un.d_val;
439 break;
440 case DT_RELA:
441 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
442 break;
443 case DT_RELASZ:
444 ef->relasize = dp->d_un.d_val;
445 break;
446 case DT_RELAENT:
447 if (dp->d_un.d_val != sizeof(Elf_Rela))
448 return ENOEXEC;
449 break;
450 case DT_PLTREL:
451 plttype = dp->d_un.d_val;
452 if (plttype != DT_REL && plttype != DT_RELA)
453 return ENOEXEC;
454 break;
455#ifdef GDB
456 case DT_DEBUG:
457 dp->d_un.d_ptr = (Elf_Addr) &r_debug;
458 break;
459#endif
460 }
461 }
462
463 if (plttype == DT_RELA) {
464 ef->pltrela = (const Elf_Rela *) ef->pltrel;
465 ef->pltrel = NULL;
466 ef->pltrelasize = ef->pltrelsize;
467 ef->pltrelsize = 0;
468 }
469
470 ef->ddbsymtab = ef->symtab;
471 ef->ddbsymcnt = ef->nchains;
472 ef->ddbstrtab = ef->strtab;
473 ef->ddbstrcnt = ef->strsz;
474
475 return 0;
476}
477
478static int
479link_elf_link_preload(linker_class_t cls,
480 const char* filename, linker_file_t *result)
481{
482 caddr_t modptr, baseptr, sizeptr, dynptr;
483 char *type;
484 elf_file_t ef;
485 linker_file_t lf;
486 int error;
487 vm_offset_t dp;
488
489 /* Look to see if we have the file preloaded */
490 modptr = preload_search_by_name(filename);
491 if (modptr == NULL)
492 return ENOENT;
493
494 type = (char *)preload_search_info(modptr, MODINFO_TYPE);
495 baseptr = preload_search_info(modptr, MODINFO_ADDR);
496 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
497 dynptr = preload_search_info(modptr, MODINFO_METADATA|MODINFOMD_DYNAMIC);
498 if (type == NULL ||
499 (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 &&
500 strcmp(type, "elf module") != 0))
501 return (EFTYPE);
502 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
503 return (EINVAL);
504
505 lf = linker_make_file(filename, &link_elf_class);
506 if (lf == NULL) {
507 return ENOMEM;
508 }
509
510 ef = (elf_file_t) lf;
511 ef->preloaded = 1;
512 ef->modptr = modptr;
513 ef->address = *(caddr_t *)baseptr;
514#ifdef SPARSE_MAPPING
515 ef->object = 0;
516#endif
517 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
518 ef->dynamic = (Elf_Dyn *)dp;
519 lf->address = ef->address;
520 lf->size = *(size_t *)sizeptr;
521
522 error = parse_dynamic(ef);
523 if (error) {
524 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
525 return error;
526 }
527 link_elf_reloc_local(lf);
528 *result = lf;
529 return (0);
530}
531
532static int
533link_elf_link_preload_finish(linker_file_t lf)
534{
535 elf_file_t ef;
536 int error;
537
538 ef = (elf_file_t) lf;
539#if 0 /* this will be more trouble than it's worth for now */
540 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
541 if (dp->d_tag != DT_NEEDED)
542 continue;
543 modname = ef->strtab + dp->d_un.d_val;
544 error = linker_load_module(modname, lf);
545 if (error)
546 goto out;
547 }
548#endif
549 error = relocate_file(ef);
550 if (error)
551 return error;
552 (void)link_elf_preload_parse_symbols(ef);
553
554 return (link_elf_link_common_finish(lf));
555}
556
557static int
558link_elf_load_file(linker_class_t cls, const char* filename,
559 linker_file_t* result)
560{
561 struct nameidata nd;
562 struct thread* td = curthread; /* XXX */
563 Elf_Ehdr *hdr;
564 caddr_t firstpage;
565 int nbytes, i;
566 Elf_Phdr *phdr;
567 Elf_Phdr *phlimit;
568 Elf_Phdr *segs[MAXSEGS];
569 int nsegs;
570 Elf_Phdr *phdyn;
571 Elf_Phdr *phphdr;
572 caddr_t mapbase;
573 size_t mapsize;
574 Elf_Off base_offset;
575 Elf_Addr base_vaddr;
576 Elf_Addr base_vlimit;
577 int error = 0;
578 int resid, flags;
579 elf_file_t ef;
580 linker_file_t lf;
581 Elf_Shdr *shdr;
582 int symtabindex;
583 int symstrindex;
584 int symcnt;
585 int strcnt;
586 int vfslocked;
587
588 shdr = NULL;
589 lf = NULL;
590
591 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, filename, td);
592 flags = FREAD;
593 error = vn_open(&nd, &flags, 0, NULL);
594 if (error)
595 return error;
596 vfslocked = NDHASGIANT(&nd);
597 NDFREE(&nd, NDF_ONLY_PNBUF);
598 if (nd.ni_vp->v_type != VREG) {
599 error = ENOEXEC;
600 firstpage = NULL;
601 goto out;
602 }
603#ifdef MAC
604 error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp);
605 if (error) {
606 firstpage = NULL;
607 goto out;
608 }
609#endif
610
611 /*
612 * Read the elf header from the file.
613 */
614 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK);
615 if (firstpage == NULL) {
616 error = ENOMEM;
617 goto out;
618 }
619 hdr = (Elf_Ehdr *)firstpage;
620 error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0,
621 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
622 &resid, td);
623 nbytes = PAGE_SIZE - resid;
624 if (error)
625 goto out;
626
627 if (!IS_ELF(*hdr)) {
628 error = ENOEXEC;
629 goto out;
630 }
631
632 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
633 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
634 link_elf_error(filename, "Unsupported file layout");
635 error = ENOEXEC;
636 goto out;
637 }
638 if (hdr->e_ident[EI_VERSION] != EV_CURRENT
639 || hdr->e_version != EV_CURRENT) {
640 link_elf_error(filename, "Unsupported file version");
641 error = ENOEXEC;
642 goto out;
643 }
644 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
645 error = ENOSYS;
646 goto out;
647 }
648 if (hdr->e_machine != ELF_TARG_MACH) {
649 link_elf_error(filename, "Unsupported machine");
650 error = ENOEXEC;
651 goto out;
652 }
653
654 /*
655 * We rely on the program header being in the first page. This is
656 * not strictly required by the ABI specification, but it seems to
657 * always true in practice. And, it simplifies things considerably.
658 */
659 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
660 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
661 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
662 link_elf_error(filename, "Unreadable program headers");
663
664 /*
665 * Scan the program header entries, and save key information.
666 *
667 * We rely on there being exactly two load segments, text and data,
668 * in that order.
669 */
670 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
671 phlimit = phdr + hdr->e_phnum;
672 nsegs = 0;
673 phdyn = NULL;
674 phphdr = NULL;
675 while (phdr < phlimit) {
676 switch (phdr->p_type) {
677
678 case PT_LOAD:
679 if (nsegs == MAXSEGS) {
680 link_elf_error(filename, "Too many sections");
681 error = ENOEXEC;
682 goto out;
683 }
684 /*
685 * XXX: We just trust they come in right order ??
686 */
687 segs[nsegs] = phdr;
688 ++nsegs;
689 break;
690
691 case PT_PHDR:
692 phphdr = phdr;
693 break;
694
695 case PT_DYNAMIC:
696 phdyn = phdr;
697 break;
698
699 case PT_INTERP:
700 error = ENOSYS;
701 goto out;
702 }
703
704 ++phdr;
705 }
706 if (phdyn == NULL) {
707 link_elf_error(filename, "Object is not dynamically-linked");
708 error = ENOEXEC;
709 goto out;
710 }
711 if (nsegs == 0) {
712 link_elf_error(filename, "No sections");
713 error = ENOEXEC;
714 goto out;
715 }
716
717 /*
718 * Allocate the entire address space of the object, to stake out our
719 * contiguous region, and to establish the base address for relocation.
720 */
721 base_offset = trunc_page(segs[0]->p_offset);
722 base_vaddr = trunc_page(segs[0]->p_vaddr);
723 base_vlimit = round_page(segs[nsegs - 1]->p_vaddr +
724 segs[nsegs - 1]->p_memsz);
725 mapsize = base_vlimit - base_vaddr;
726
727 lf = linker_make_file(filename, &link_elf_class);
728 if (!lf) {
729 error = ENOMEM;
730 goto out;
731 }
732
733 ef = (elf_file_t) lf;
734#ifdef SPARSE_MAPPING
735 ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
736 if (ef->object == NULL) {
737 error = ENOMEM;
738 goto out;
739 }
740 ef->address = (caddr_t) vm_map_min(kernel_map);
741 error = vm_map_find(kernel_map, ef->object, 0,
742 (vm_offset_t *) &ef->address,
743 mapsize, 1,
744 VM_PROT_ALL, VM_PROT_ALL, 0);
745 if (error) {
746 vm_object_deallocate(ef->object);
747 ef->object = 0;
748 goto out;
749 }
750#else
751 ef->address = malloc(mapsize, M_LINKER, M_WAITOK);
752 if (!ef->address) {
753 error = ENOMEM;
754 goto out;
755 }
756#endif
757 mapbase = ef->address;
758
759 /*
760 * Read the text and data sections and zero the bss.
761 */
762 for (i = 0; i < nsegs; i++) {
763 caddr_t segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
764 error = vn_rdwr(UIO_READ, nd.ni_vp,
765 segbase, segs[i]->p_filesz, segs[i]->p_offset,
766 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
767 &resid, td);
768 if (error) {
769 goto out;
770 }
771 bzero(segbase + segs[i]->p_filesz,
772 segs[i]->p_memsz - segs[i]->p_filesz);
773
774#ifdef SPARSE_MAPPING
775 /*
776 * Wire down the pages
777 */
778 error = vm_map_wire(kernel_map,
779 (vm_offset_t) segbase,
780 (vm_offset_t) segbase + segs[i]->p_memsz,
781 VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
782 if (error != KERN_SUCCESS) {
783 error = ENOMEM;
784 goto out;
785 }
786#endif
787 }
788
789#ifdef GPROF
790 /* Update profiling information with the new text segment. */
791 mtx_lock(&Giant);
792 kmupetext((uintfptr_t)(mapbase + segs[0]->p_vaddr - base_vaddr +
793 segs[0]->p_memsz));
794 mtx_unlock(&Giant);
795#endif
796
797 ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
798
799 lf->address = ef->address;
800 lf->size = mapsize;
801
802 error = parse_dynamic(ef);
803 if (error)
804 goto out;
805 link_elf_reloc_local(lf);
806
807 VOP_UNLOCK(nd.ni_vp, 0);
808 error = linker_load_dependencies(lf);
809 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
810 if (error)
811 goto out;
812#if 0 /* this will be more trouble than it's worth for now */
813 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
814 if (dp->d_tag != DT_NEEDED)
815 continue;
816 modname = ef->strtab + dp->d_un.d_val;
817 error = linker_load_module(modname, lf);
818 if (error)
819 goto out;
820 }
821#endif
822 error = relocate_file(ef);
823 if (error)
824 goto out;
825
826 /* Try and load the symbol table if it's present. (you can strip it!) */
827 nbytes = hdr->e_shnum * hdr->e_shentsize;
828 if (nbytes == 0 || hdr->e_shoff == 0)
829 goto nosyms;
830 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
831 if (shdr == NULL) {
832 error = ENOMEM;
833 goto out;
834 }
835 error = vn_rdwr(UIO_READ, nd.ni_vp,
836 (caddr_t)shdr, nbytes, hdr->e_shoff,
837 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
838 &resid, td);
839 if (error)
840 goto out;
841 symtabindex = -1;
842 symstrindex = -1;
843 for (i = 0; i < hdr->e_shnum; i++) {
844 if (shdr[i].sh_type == SHT_SYMTAB) {
845 symtabindex = i;
846 symstrindex = shdr[i].sh_link;
847 }
848 }
849 if (symtabindex < 0 || symstrindex < 0)
850 goto nosyms;
851
852 symcnt = shdr[symtabindex].sh_size;
853 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK);
854 strcnt = shdr[symstrindex].sh_size;
855 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK);
856
857 if (ef->symbase == NULL || ef->strbase == NULL) {
858 error = ENOMEM;
859 goto out;
860 }
861 error = vn_rdwr(UIO_READ, nd.ni_vp,
862 ef->symbase, symcnt, shdr[symtabindex].sh_offset,
863 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
864 &resid, td);
865 if (error)
866 goto out;
867 error = vn_rdwr(UIO_READ, nd.ni_vp,
868 ef->strbase, strcnt, shdr[symstrindex].sh_offset,
869 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
870 &resid, td);
871 if (error)
872 goto out;
873
874 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
875 ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
876 ef->ddbstrcnt = strcnt;
877 ef->ddbstrtab = ef->strbase;
878
879 error = link_elf_link_common_finish(lf);
880 if (error)
881 goto out;
882
883nosyms:
884
885 *result = lf;
886
887out:
888 if (error && lf)
889 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
890 if (shdr)
891 free(shdr, M_LINKER);
892 if (firstpage)
893 free(firstpage, M_LINKER);
894 VOP_UNLOCK(nd.ni_vp, 0);
895 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
896 VFS_UNLOCK_GIANT(vfslocked);
897
898 return error;
899}
900
901static void
902link_elf_unload_file(linker_file_t file)
903{
904 elf_file_t ef = (elf_file_t) file;
905
906#ifdef GDB
907 if (ef->gdb.l_ld) {
908 GDB_STATE(RT_DELETE);
909 free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER);
910 link_elf_delete_gdb(&ef->gdb);
911 GDB_STATE(RT_CONSISTENT);
912 }
913#endif
914
915 /* Notify MD code that a module is being unloaded. */
916 elf_cpu_unload_file(file);
917
918 if (ef->preloaded) {
919 link_elf_unload_preload(file);
920 return;
921 }
922
923#ifdef SPARSE_MAPPING
924 if (ef->object) {
925 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
926 (vm_offset_t) ef->address
927 + (ef->object->size << PAGE_SHIFT));
928 }
929#else
930 if (ef->address)
931 free(ef->address, M_LINKER);
932#endif
933 if (ef->symbase)
934 free(ef->symbase, M_LINKER);
935 if (ef->strbase)
936 free(ef->strbase, M_LINKER);
937 if (ef->ctftab)
938 free(ef->ctftab, M_LINKER);
939 if (ef->ctfoff)
940 free(ef->ctfoff, M_LINKER);
941 if (ef->typoff)
942 free(ef->typoff, M_LINKER);
943}
944
945static void
946link_elf_unload_preload(linker_file_t file)
947{
948 if (file->filename)
949 preload_delete_name(file->filename);
950}
951
952static const char *
953symbol_name(elf_file_t ef, Elf_Size r_info)
954{
955 const Elf_Sym *ref;
956
957 if (ELF_R_SYM(r_info)) {
958 ref = ef->symtab + ELF_R_SYM(r_info);
959 return ef->strtab + ref->st_name;
960 } else
961 return NULL;
962}
963
964static int
965relocate_file(elf_file_t ef)
966{
967 const Elf_Rel *rellim;
968 const Elf_Rel *rel;
969 const Elf_Rela *relalim;
970 const Elf_Rela *rela;
971 const char *symname;
972
973 /* Perform relocations without addend if there are any: */
974 rel = ef->rel;
975 if (rel) {
976 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
977 while (rel < rellim) {
978 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
979 elf_lookup)) {
980 symname = symbol_name(ef, rel->r_info);
981 printf("link_elf: symbol %s undefined\n", symname);
982 return ENOENT;
983 }
984 rel++;
985 }
986 }
987
988 /* Perform relocations with addend if there are any: */
989 rela = ef->rela;
990 if (rela) {
991 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
992 while (rela < relalim) {
993 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
994 elf_lookup)) {
995 symname = symbol_name(ef, rela->r_info);
996 printf("link_elf: symbol %s undefined\n", symname);
997 return ENOENT;
998 }
999 rela++;
1000 }
1001 }
1002
1003 /* Perform PLT relocations without addend if there are any: */
1004 rel = ef->pltrel;
1005 if (rel) {
1006 rellim = (const Elf_Rel *)((const char *)ef->pltrel + ef->pltrelsize);
1007 while (rel < rellim) {
1008 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
1009 elf_lookup)) {
1010 symname = symbol_name(ef, rel->r_info);
1011 printf("link_elf: symbol %s undefined\n", symname);
1012 return ENOENT;
1013 }
1014 rel++;
1015 }
1016 }
1017
1018 /* Perform relocations with addend if there are any: */
1019 rela = ef->pltrela;
1020 if (rela) {
1021 relalim = (const Elf_Rela *)((const char *)ef->pltrela + ef->pltrelasize);
1022 while (rela < relalim) {
1023 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
1024 elf_lookup)) {
1025 symname = symbol_name(ef, rela->r_info);
1026 printf("link_elf: symbol %s undefined\n", symname);
1027 return ENOENT;
1028 }
1029 rela++;
1030 }
1031 }
1032
1033 return 0;
1034}
1035
1036/*
1037 * Hash function for symbol table lookup. Don't even think about changing
1038 * this. It is specified by the System V ABI.
1039 */
1040static unsigned long
1041elf_hash(const char *name)
1042{
1043 const unsigned char *p = (const unsigned char *) name;
1044 unsigned long h = 0;
1045 unsigned long g;
1046
1047 while (*p != '\0') {
1048 h = (h << 4) + *p++;
1049 if ((g = h & 0xf0000000) != 0)
1050 h ^= g >> 24;
1051 h &= ~g;
1052 }
1053 return h;
1054}
1055
1056static int
1057link_elf_lookup_symbol(linker_file_t lf, const char* name, c_linker_sym_t* sym)
1058{
1059 elf_file_t ef = (elf_file_t) lf;
1060 unsigned long symnum;
1061 const Elf_Sym* symp;
1062 const char *strp;
1063 unsigned long hash;
1064 int i;
1065
1066 /* If we don't have a hash, bail. */
1067 if (ef->buckets == NULL || ef->nbuckets == 0) {
1068 printf("link_elf_lookup_symbol: missing symbol hash table\n");
1069 return ENOENT;
1070 }
1071
1072 /* First, search hashed global symbols */
1073 hash = elf_hash(name);
1074 symnum = ef->buckets[hash % ef->nbuckets];
1075
1076 while (symnum != STN_UNDEF) {
1077 if (symnum >= ef->nchains) {
1078 printf("link_elf_lookup_symbol: corrupt symbol table\n");
1079 return ENOENT;
1080 }
1081
1082 symp = ef->symtab + symnum;
1083 if (symp->st_name == 0) {
1084 printf("link_elf_lookup_symbol: corrupt symbol table\n");
1085 return ENOENT;
1086 }
1087
1088 strp = ef->strtab + symp->st_name;
1089
1090 if (strcmp(name, strp) == 0) {
1091 if (symp->st_shndx != SHN_UNDEF ||
1092 (symp->st_value != 0 &&
1093 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
1094 *sym = (c_linker_sym_t) symp;
1095 return 0;
1096 } else
1097 return ENOENT;
1098 }
1099
1100 symnum = ef->chains[symnum];
1101 }
1102
1103 /* If we have not found it, look at the full table (if loaded) */
1104 if (ef->symtab == ef->ddbsymtab)
1105 return ENOENT;
1106
1107 /* Exhaustive search */
1108 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1109 strp = ef->ddbstrtab + symp->st_name;
1110 if (strcmp(name, strp) == 0) {
1111 if (symp->st_shndx != SHN_UNDEF ||
1112 (symp->st_value != 0 &&
1113 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
1114 *sym = (c_linker_sym_t) symp;
1115 return 0;
1116 } else
1117 return ENOENT;
1118 }
1119 }
1120
1121 return ENOENT;
1122}
1123
1124static int
1125link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, linker_symval_t* symval)
1126{
1127 elf_file_t ef = (elf_file_t) lf;
1128 const Elf_Sym* es = (const Elf_Sym*) sym;
1129
1130 if (es >= ef->symtab && es < (ef->symtab + ef->nchains)) {
1131 symval->name = ef->strtab + es->st_name;
1132 symval->value = (caddr_t) ef->address + es->st_value;
1133 symval->size = es->st_size;
1134 return 0;
1135 }
1136 if (ef->symtab == ef->ddbsymtab)
1137 return ENOENT;
1138 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1139 symval->name = ef->ddbstrtab + es->st_name;
1140 symval->value = (caddr_t) ef->address + es->st_value;
1141 symval->size = es->st_size;
1142 return 0;
1143 }
1144 return ENOENT;
1145}
1146
1147static int
1148link_elf_search_symbol(linker_file_t lf, caddr_t value,
1149 c_linker_sym_t* sym, long* diffp)
1150{
1151 elf_file_t ef = (elf_file_t) lf;
1152 u_long off = (uintptr_t) (void *) value;
1153 u_long diff = off;
1154 u_long st_value;
1155 const Elf_Sym* es;
1156 const Elf_Sym* best = 0;
1157 int i;
1158
1159 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1160 if (es->st_name == 0)
1161 continue;
1162 st_value = es->st_value + (uintptr_t) (void *) ef->address;
1163 if (off >= st_value) {
1164 if (off - st_value < diff) {
1165 diff = off - st_value;
1166 best = es;
1167 if (diff == 0)
1168 break;
1169 } else if (off - st_value == diff) {
1170 best = es;
1171 }
1172 }
1173 }
1174 if (best == 0)
1175 *diffp = off;
1176 else
1177 *diffp = diff;
1178 *sym = (c_linker_sym_t) best;
1179
1180 return 0;
1181}
1182
1183/*
1184 * Look up a linker set on an ELF system.
1185 */
1186static int
1187link_elf_lookup_set(linker_file_t lf, const char *name,
1188 void ***startp, void ***stopp, int *countp)
1189{
1190 c_linker_sym_t sym;
1191 linker_symval_t symval;
1192 char *setsym;
1193 void **start, **stop;
1194 int len, error = 0, count;
1195
1196 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
1197 setsym = malloc(len, M_LINKER, M_WAITOK);
1198 if (setsym == NULL)
1199 return ENOMEM;
1200
1201 /* get address of first entry */
1202 snprintf(setsym, len, "%s%s", "__start_set_", name);
1203 error = link_elf_lookup_symbol(lf, setsym, &sym);
1204 if (error)
1205 goto out;
1206 link_elf_symbol_values(lf, sym, &symval);
1207 if (symval.value == 0) {
1208 error = ESRCH;
1209 goto out;
1210 }
1211 start = (void **)symval.value;
1212
1213 /* get address of last entry */
1214 snprintf(setsym, len, "%s%s", "__stop_set_", name);
1215 error = link_elf_lookup_symbol(lf, setsym, &sym);
1216 if (error)
1217 goto out;
1218 link_elf_symbol_values(lf, sym, &symval);
1219 if (symval.value == 0) {
1220 error = ESRCH;
1221 goto out;
1222 }
1223 stop = (void **)symval.value;
1224
1225 /* and the number of entries */
1226 count = stop - start;
1227
1228 /* and copy out */
1229 if (startp)
1230 *startp = start;
1231 if (stopp)
1232 *stopp = stop;
1233 if (countp)
1234 *countp = count;
1235
1236out:
1237 free(setsym, M_LINKER);
1238 return error;
1239}
1240
1241static int
1242link_elf_each_function_name(linker_file_t file,
1243 int (*callback)(const char *, void *), void *opaque) {
1244 elf_file_t ef = (elf_file_t)file;
1245 const Elf_Sym* symp;
1246 int i, error;
1247
1248 /* Exhaustive search */
1249 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1250 if (symp->st_value != 0 &&
1251 ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1252 error = callback(ef->ddbstrtab + symp->st_name, opaque);
1253 if (error)
1254 return (error);
1255 }
1256 }
1257 return (0);
1258}
1259
1260static int
1261link_elf_each_function_nameval(linker_file_t file,
1262 linker_function_nameval_callback_t callback, void *opaque)
1263{
1264 linker_symval_t symval;
1265 elf_file_t ef = (elf_file_t)file;
1266 const Elf_Sym* symp;
1267 int i, error;
1268
1269 /* Exhaustive search */
1270 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1271 if (symp->st_value != 0 &&
1272 ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1273 error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval);
1274 if (error)
1275 return (error);
1276 error = callback(file, i, &symval, opaque);
1277 if (error)
1278 return (error);
1279 }
1280 }
1281 return (0);
1282}
1283
1284#ifdef __ia64__
1285/*
1286 * Each KLD has its own GP. The GP value for each load module is given by
1287 * DT_PLTGOT on ia64. We need GP to construct function descriptors, but
1288 * don't have direct access to the ELF file structure. The link_elf_get_gp()
1289 * function returns the GP given a pointer to a generic linker file struct.
1290 */
1291Elf_Addr
1292link_elf_get_gp(linker_file_t lf)
1293{
1294 elf_file_t ef = (elf_file_t)lf;
1295 return (Elf_Addr)ef->got;
1296}
1297#endif
1298
1299const Elf_Sym *
1300elf_get_sym(linker_file_t lf, Elf_Size symidx)
1301{
1302 elf_file_t ef = (elf_file_t)lf;
1303
1304 if (symidx >= ef->nchains)
1305 return (NULL);
1306 return (ef->symtab + symidx);
1307}
1308
1309const char *
1310elf_get_symname(linker_file_t lf, Elf_Size symidx)
1311{
1312 elf_file_t ef = (elf_file_t)lf;
1313 const Elf_Sym *sym;
1314
1315 if (symidx >= ef->nchains)
1316 return (NULL);
1317 sym = ef->symtab + symidx;
1318 return (ef->strtab + sym->st_name);
1319}
1320
1321/*
1322 * Symbol lookup function that can be used when the symbol index is known (ie
1323 * in relocations). It uses the symbol index instead of doing a fully fledged
1324 * hash table based lookup when such is valid. For example for local symbols.
1325 * This is not only more efficient, it's also more correct. It's not always
1326 * the case that the symbol can be found through the hash table.
1327 */
1328static Elf_Addr
1329elf_lookup(linker_file_t lf, Elf_Size symidx, int deps)
1330{
1331 elf_file_t ef = (elf_file_t)lf;
1332 const Elf_Sym *sym;
1333 const char *symbol;
1334
1335 /* Don't even try to lookup the symbol if the index is bogus. */
1336 if (symidx >= ef->nchains)
1337 return (0);
1338
1339 sym = ef->symtab + symidx;
1340
1341 /*
1342 * Don't do a full lookup when the symbol is local. It may even
1343 * fail because it may not be found through the hash table.
1344 */
1345 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
1346 /* Force lookup failure when we have an insanity. */
1347 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0)
1348 return (0);
1349 return ((Elf_Addr)ef->address + sym->st_value);
1350 }
1351
1352 /*
1353 * XXX we can avoid doing a hash table based lookup for global
1354 * symbols as well. This however is not always valid, so we'll
1355 * just do it the hard way for now. Performance tweaks can
1356 * always be added.
1357 */
1358
1359 symbol = ef->strtab + sym->st_name;
1360
1361 /* Force a lookup failure if the symbol name is bogus. */
1362 if (*symbol == 0)
1363 return (0);
1364
1365 return ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1366}
1367
1368static void
1369link_elf_reloc_local(linker_file_t lf)
1370{
1371 const Elf_Rel *rellim;
1372 const Elf_Rel *rel;
1373 const Elf_Rela *relalim;
1374 const Elf_Rela *rela;
1375 elf_file_t ef = (elf_file_t)lf;
1376
1377 /* Perform relocations without addend if there are any: */
1378 if ((rel = ef->rel) != NULL) {
1379 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
1380 while (rel < rellim) {
1381 elf_reloc_local(lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
1382 elf_lookup);
1383 rel++;
1384 }
1385 }
1386
1387 /* Perform relocations with addend if there are any: */
1388 if ((rela = ef->rela) != NULL) {
1389 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
1390 while (rela < relalim) {
1391 elf_reloc_local(lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
1392 elf_lookup);
1393 rela++;
1394 }
1395 }
1396}
1397
1398static long
1399link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1400{
1401 elf_file_t ef = (elf_file_t)lf;
1402
1403 *symtab = ef->ddbsymtab;
1404
1405 if (*symtab == NULL)
1406 return (0);
1407
1408 return (ef->ddbsymcnt);
1409}
1410
1411static long
1412link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1413{
1414 elf_file_t ef = (elf_file_t)lf;
1415
1416 *strtab = ef->ddbstrtab;
1417
1418 if (*strtab == NULL)
1419 return (0);
1420
1421 return (ef->ddbstrcnt);
1422}
2 * Copyright (c) 1998-2000 Doug Rabson
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/kern/link_elf.c 192859 2009-05-26 21:39:09Z sson $");
29
30#include "opt_ddb.h"
31#include "opt_gdb.h"
32#include "opt_mac.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#ifdef GPROF
37#include <sys/gmon.h>
38#endif
39#include <sys/kernel.h>
40#include <sys/lock.h>
41#include <sys/malloc.h>
42#include <sys/mutex.h>
43#include <sys/mount.h>
44#include <sys/proc.h>
45#include <sys/namei.h>
46#include <sys/fcntl.h>
47#include <sys/vnode.h>
48#include <sys/linker.h>
49
50#include <machine/elf.h>
51
52#include <security/mac/mac_framework.h>
53
54#include <vm/vm.h>
55#include <vm/vm_param.h>
56#ifdef SPARSE_MAPPING
57#include <vm/vm_object.h>
58#include <vm/vm_kern.h>
59#include <vm/vm_extern.h>
60#endif
61#include <vm/pmap.h>
62#include <vm/vm_map.h>
63
64#include <sys/link_elf.h>
65
66#ifdef DDB_CTF
67#include <net/zlib.h>
68#endif
69
70#include "linker_if.h"
71
72#define MAXSEGS 4
73
74typedef struct elf_file {
75 struct linker_file lf; /* Common fields */
76 int preloaded; /* Was file pre-loaded */
77 caddr_t address; /* Relocation address */
78#ifdef SPARSE_MAPPING
79 vm_object_t object; /* VM object to hold file pages */
80#endif
81 Elf_Dyn* dynamic; /* Symbol table etc. */
82 Elf_Hashelt nbuckets; /* DT_HASH info */
83 Elf_Hashelt nchains;
84 const Elf_Hashelt* buckets;
85 const Elf_Hashelt* chains;
86 caddr_t hash;
87 caddr_t strtab; /* DT_STRTAB */
88 int strsz; /* DT_STRSZ */
89 const Elf_Sym* symtab; /* DT_SYMTAB */
90 Elf_Addr* got; /* DT_PLTGOT */
91 const Elf_Rel* pltrel; /* DT_JMPREL */
92 int pltrelsize; /* DT_PLTRELSZ */
93 const Elf_Rela* pltrela; /* DT_JMPREL */
94 int pltrelasize; /* DT_PLTRELSZ */
95 const Elf_Rel* rel; /* DT_REL */
96 int relsize; /* DT_RELSZ */
97 const Elf_Rela* rela; /* DT_RELA */
98 int relasize; /* DT_RELASZ */
99 caddr_t modptr;
100 const Elf_Sym* ddbsymtab; /* The symbol table we are using */
101 long ddbsymcnt; /* Number of symbols */
102 caddr_t ddbstrtab; /* String table */
103 long ddbstrcnt; /* number of bytes in string table */
104 caddr_t symbase; /* malloc'ed symbold base */
105 caddr_t strbase; /* malloc'ed string base */
106 caddr_t ctftab; /* CTF table */
107 long ctfcnt; /* number of bytes in CTF table */
108 caddr_t ctfoff; /* CTF offset table */
109 caddr_t typoff; /* Type offset table */
110 long typlen; /* Number of type entries. */
111#ifdef GDB
112 struct link_map gdb; /* hooks for gdb */
113#endif
114} *elf_file_t;
115
116#include <kern/kern_ctf.c>
117
118static int link_elf_link_common_finish(linker_file_t);
119static int link_elf_link_preload(linker_class_t cls,
120 const char*, linker_file_t*);
121static int link_elf_link_preload_finish(linker_file_t);
122static int link_elf_load_file(linker_class_t, const char*, linker_file_t*);
123static int link_elf_lookup_symbol(linker_file_t, const char*,
124 c_linker_sym_t*);
125static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t*);
126static int link_elf_search_symbol(linker_file_t, caddr_t value,
127 c_linker_sym_t* sym, long* diffp);
128
129static void link_elf_unload_file(linker_file_t);
130static void link_elf_unload_preload(linker_file_t);
131static int link_elf_lookup_set(linker_file_t, const char *,
132 void ***, void ***, int *);
133static int link_elf_each_function_name(linker_file_t,
134 int (*)(const char *, void *),
135 void *);
136static int link_elf_each_function_nameval(linker_file_t,
137 linker_function_nameval_callback_t,
138 void *);
139static void link_elf_reloc_local(linker_file_t);
140static long link_elf_symtab_get(linker_file_t, const Elf_Sym **);
141static long link_elf_strtab_get(linker_file_t, caddr_t *);
142static Elf_Addr elf_lookup(linker_file_t lf, Elf_Size symidx, int deps);
143
144static kobj_method_t link_elf_methods[] = {
145 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol),
146 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values),
147 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol),
148 KOBJMETHOD(linker_unload, link_elf_unload_file),
149 KOBJMETHOD(linker_load_file, link_elf_load_file),
150 KOBJMETHOD(linker_link_preload, link_elf_link_preload),
151 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish),
152 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set),
153 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name),
154 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval),
155 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get),
156 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get),
157 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get),
158 { 0, 0 }
159};
160
161static struct linker_class link_elf_class = {
162#if ELF_TARG_CLASS == ELFCLASS32
163 "elf32",
164#else
165 "elf64",
166#endif
167 link_elf_methods, sizeof(struct elf_file)
168};
169
170static int parse_dynamic(elf_file_t ef);
171static int relocate_file(elf_file_t ef);
172static int link_elf_preload_parse_symbols(elf_file_t ef);
173
174#ifdef GDB
175static void r_debug_state(struct r_debug *dummy_one,
176 struct link_map *dummy_two);
177
178/*
179 * A list of loaded modules for GDB to use for loading symbols.
180 */
181struct r_debug r_debug;
182
183#define GDB_STATE(s) r_debug.r_state = s; r_debug_state(NULL, NULL);
184
185/*
186 * Function for the debugger to set a breakpoint on to gain control.
187 */
188static void
189r_debug_state(struct r_debug *dummy_one __unused,
190 struct link_map *dummy_two __unused)
191{
192}
193
194static void
195link_elf_add_gdb(struct link_map *l)
196{
197 struct link_map *prev;
198
199 l->l_next = NULL;
200
201 if (r_debug.r_map == NULL) {
202 /* Add first. */
203 l->l_prev = NULL;
204 r_debug.r_map = l;
205 } else {
206 /* Append to list. */
207 for (prev = r_debug.r_map; prev->l_next != NULL; prev = prev->l_next)
208 ;
209 l->l_prev = prev;
210 prev->l_next = l;
211 }
212}
213
214static void
215link_elf_delete_gdb(struct link_map *l)
216{
217 if (l->l_prev == NULL) {
218 /* Remove first. */
219 if ((r_debug.r_map = l->l_next) != NULL)
220 l->l_next->l_prev = NULL;
221 } else {
222 /* Remove any but first. */
223 if ((l->l_prev->l_next = l->l_next) != NULL)
224 l->l_next->l_prev = l->l_prev;
225 }
226}
227#endif /* GDB */
228
229#ifdef __ia64__
230Elf_Addr link_elf_get_gp(linker_file_t);
231#endif
232
233/*
234 * The kernel symbol table starts here.
235 */
236extern struct _dynamic _DYNAMIC;
237
238static void
239link_elf_error(const char *filename, const char *s)
240{
241 if (filename == NULL)
242 printf("kldload: %s\n", s);
243 else
244 printf("kldload: %s: %s\n", filename, s);
245}
246
247/*
248 * Actions performed after linking/loading both the preloaded kernel and any
249 * modules; whether preloaded or dynamicly loaded.
250 */
251static int
252link_elf_link_common_finish(linker_file_t lf)
253{
254#ifdef GDB
255 elf_file_t ef = (elf_file_t)lf;
256 char *newfilename;
257#endif
258 int error;
259
260 /* Notify MD code that a module is being loaded. */
261 error = elf_cpu_load_file(lf);
262 if (error)
263 return (error);
264
265#ifdef GDB
266 GDB_STATE(RT_ADD);
267 ef->gdb.l_addr = lf->address;
268 newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK);
269 strcpy(newfilename, lf->filename);
270 ef->gdb.l_name = newfilename;
271 ef->gdb.l_ld = ef->dynamic;
272 link_elf_add_gdb(&ef->gdb);
273 GDB_STATE(RT_CONSISTENT);
274#endif
275
276 return (0);
277}
278
279static void
280link_elf_init(void* arg)
281{
282 Elf_Dyn *dp;
283 caddr_t modptr, baseptr, sizeptr;
284 elf_file_t ef;
285 char *modname;
286
287 linker_add_class(&link_elf_class);
288
289 dp = (Elf_Dyn*) &_DYNAMIC;
290 modname = NULL;
291 modptr = preload_search_by_type("elf" __XSTRING(__ELF_WORD_SIZE) " kernel");
292 if (modptr == NULL)
293 modptr = preload_search_by_type("elf kernel");
294 if (modptr)
295 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
296 if (modname == NULL)
297 modname = "kernel";
298 linker_kernel_file = linker_make_file(modname, &link_elf_class);
299 if (linker_kernel_file == NULL)
300 panic("link_elf_init: Can't create linker structures for kernel");
301
302 ef = (elf_file_t) linker_kernel_file;
303 ef->preloaded = 1;
304 ef->address = 0;
305#ifdef SPARSE_MAPPING
306 ef->object = 0;
307#endif
308 ef->dynamic = dp;
309
310 if (dp)
311 parse_dynamic(ef);
312 linker_kernel_file->address = (caddr_t) KERNBASE;
313 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
314
315 if (modptr) {
316 ef->modptr = modptr;
317 baseptr = preload_search_info(modptr, MODINFO_ADDR);
318 if (baseptr)
319 linker_kernel_file->address = *(caddr_t *)baseptr;
320 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
321 if (sizeptr)
322 linker_kernel_file->size = *(size_t *)sizeptr;
323 }
324 (void)link_elf_preload_parse_symbols(ef);
325
326#ifdef GDB
327 r_debug.r_map = NULL;
328 r_debug.r_brk = r_debug_state;
329 r_debug.r_state = RT_CONSISTENT;
330#endif
331
332 (void)link_elf_link_common_finish(linker_kernel_file);
333 linker_kernel_file->flags |= LINKER_FILE_LINKED;
334}
335
336SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, 0);
337
338static int
339link_elf_preload_parse_symbols(elf_file_t ef)
340{
341 caddr_t pointer;
342 caddr_t ssym, esym, base;
343 caddr_t strtab;
344 int strcnt;
345 Elf_Sym* symtab;
346 int symcnt;
347
348 if (ef->modptr == NULL)
349 return 0;
350 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_SSYM);
351 if (pointer == NULL)
352 return 0;
353 ssym = *(caddr_t *)pointer;
354 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_ESYM);
355 if (pointer == NULL)
356 return 0;
357 esym = *(caddr_t *)pointer;
358
359 base = ssym;
360
361 symcnt = *(long *)base;
362 base += sizeof(long);
363 symtab = (Elf_Sym *)base;
364 base += roundup(symcnt, sizeof(long));
365
366 if (base > esym || base < ssym) {
367 printf("Symbols are corrupt!\n");
368 return EINVAL;
369 }
370
371 strcnt = *(long *)base;
372 base += sizeof(long);
373 strtab = base;
374 base += roundup(strcnt, sizeof(long));
375
376 if (base > esym || base < ssym) {
377 printf("Symbols are corrupt!\n");
378 return EINVAL;
379 }
380
381 ef->ddbsymtab = symtab;
382 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
383 ef->ddbstrtab = strtab;
384 ef->ddbstrcnt = strcnt;
385
386 return 0;
387}
388
389static int
390parse_dynamic(elf_file_t ef)
391{
392 Elf_Dyn *dp;
393 int plttype = DT_REL;
394
395 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
396 switch (dp->d_tag) {
397 case DT_HASH:
398 {
399 /* From src/libexec/rtld-elf/rtld.c */
400 const Elf_Hashelt *hashtab = (const Elf_Hashelt *)
401 (ef->address + dp->d_un.d_ptr);
402 ef->nbuckets = hashtab[0];
403 ef->nchains = hashtab[1];
404 ef->buckets = hashtab + 2;
405 ef->chains = ef->buckets + ef->nbuckets;
406 break;
407 }
408 case DT_STRTAB:
409 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
410 break;
411 case DT_STRSZ:
412 ef->strsz = dp->d_un.d_val;
413 break;
414 case DT_SYMTAB:
415 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
416 break;
417 case DT_SYMENT:
418 if (dp->d_un.d_val != sizeof(Elf_Sym))
419 return ENOEXEC;
420 break;
421 case DT_PLTGOT:
422 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
423 break;
424 case DT_REL:
425 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
426 break;
427 case DT_RELSZ:
428 ef->relsize = dp->d_un.d_val;
429 break;
430 case DT_RELENT:
431 if (dp->d_un.d_val != sizeof(Elf_Rel))
432 return ENOEXEC;
433 break;
434 case DT_JMPREL:
435 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
436 break;
437 case DT_PLTRELSZ:
438 ef->pltrelsize = dp->d_un.d_val;
439 break;
440 case DT_RELA:
441 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
442 break;
443 case DT_RELASZ:
444 ef->relasize = dp->d_un.d_val;
445 break;
446 case DT_RELAENT:
447 if (dp->d_un.d_val != sizeof(Elf_Rela))
448 return ENOEXEC;
449 break;
450 case DT_PLTREL:
451 plttype = dp->d_un.d_val;
452 if (plttype != DT_REL && plttype != DT_RELA)
453 return ENOEXEC;
454 break;
455#ifdef GDB
456 case DT_DEBUG:
457 dp->d_un.d_ptr = (Elf_Addr) &r_debug;
458 break;
459#endif
460 }
461 }
462
463 if (plttype == DT_RELA) {
464 ef->pltrela = (const Elf_Rela *) ef->pltrel;
465 ef->pltrel = NULL;
466 ef->pltrelasize = ef->pltrelsize;
467 ef->pltrelsize = 0;
468 }
469
470 ef->ddbsymtab = ef->symtab;
471 ef->ddbsymcnt = ef->nchains;
472 ef->ddbstrtab = ef->strtab;
473 ef->ddbstrcnt = ef->strsz;
474
475 return 0;
476}
477
478static int
479link_elf_link_preload(linker_class_t cls,
480 const char* filename, linker_file_t *result)
481{
482 caddr_t modptr, baseptr, sizeptr, dynptr;
483 char *type;
484 elf_file_t ef;
485 linker_file_t lf;
486 int error;
487 vm_offset_t dp;
488
489 /* Look to see if we have the file preloaded */
490 modptr = preload_search_by_name(filename);
491 if (modptr == NULL)
492 return ENOENT;
493
494 type = (char *)preload_search_info(modptr, MODINFO_TYPE);
495 baseptr = preload_search_info(modptr, MODINFO_ADDR);
496 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
497 dynptr = preload_search_info(modptr, MODINFO_METADATA|MODINFOMD_DYNAMIC);
498 if (type == NULL ||
499 (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 &&
500 strcmp(type, "elf module") != 0))
501 return (EFTYPE);
502 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
503 return (EINVAL);
504
505 lf = linker_make_file(filename, &link_elf_class);
506 if (lf == NULL) {
507 return ENOMEM;
508 }
509
510 ef = (elf_file_t) lf;
511 ef->preloaded = 1;
512 ef->modptr = modptr;
513 ef->address = *(caddr_t *)baseptr;
514#ifdef SPARSE_MAPPING
515 ef->object = 0;
516#endif
517 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
518 ef->dynamic = (Elf_Dyn *)dp;
519 lf->address = ef->address;
520 lf->size = *(size_t *)sizeptr;
521
522 error = parse_dynamic(ef);
523 if (error) {
524 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
525 return error;
526 }
527 link_elf_reloc_local(lf);
528 *result = lf;
529 return (0);
530}
531
532static int
533link_elf_link_preload_finish(linker_file_t lf)
534{
535 elf_file_t ef;
536 int error;
537
538 ef = (elf_file_t) lf;
539#if 0 /* this will be more trouble than it's worth for now */
540 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
541 if (dp->d_tag != DT_NEEDED)
542 continue;
543 modname = ef->strtab + dp->d_un.d_val;
544 error = linker_load_module(modname, lf);
545 if (error)
546 goto out;
547 }
548#endif
549 error = relocate_file(ef);
550 if (error)
551 return error;
552 (void)link_elf_preload_parse_symbols(ef);
553
554 return (link_elf_link_common_finish(lf));
555}
556
557static int
558link_elf_load_file(linker_class_t cls, const char* filename,
559 linker_file_t* result)
560{
561 struct nameidata nd;
562 struct thread* td = curthread; /* XXX */
563 Elf_Ehdr *hdr;
564 caddr_t firstpage;
565 int nbytes, i;
566 Elf_Phdr *phdr;
567 Elf_Phdr *phlimit;
568 Elf_Phdr *segs[MAXSEGS];
569 int nsegs;
570 Elf_Phdr *phdyn;
571 Elf_Phdr *phphdr;
572 caddr_t mapbase;
573 size_t mapsize;
574 Elf_Off base_offset;
575 Elf_Addr base_vaddr;
576 Elf_Addr base_vlimit;
577 int error = 0;
578 int resid, flags;
579 elf_file_t ef;
580 linker_file_t lf;
581 Elf_Shdr *shdr;
582 int symtabindex;
583 int symstrindex;
584 int symcnt;
585 int strcnt;
586 int vfslocked;
587
588 shdr = NULL;
589 lf = NULL;
590
591 NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE, UIO_SYSSPACE, filename, td);
592 flags = FREAD;
593 error = vn_open(&nd, &flags, 0, NULL);
594 if (error)
595 return error;
596 vfslocked = NDHASGIANT(&nd);
597 NDFREE(&nd, NDF_ONLY_PNBUF);
598 if (nd.ni_vp->v_type != VREG) {
599 error = ENOEXEC;
600 firstpage = NULL;
601 goto out;
602 }
603#ifdef MAC
604 error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp);
605 if (error) {
606 firstpage = NULL;
607 goto out;
608 }
609#endif
610
611 /*
612 * Read the elf header from the file.
613 */
614 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK);
615 if (firstpage == NULL) {
616 error = ENOMEM;
617 goto out;
618 }
619 hdr = (Elf_Ehdr *)firstpage;
620 error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0,
621 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
622 &resid, td);
623 nbytes = PAGE_SIZE - resid;
624 if (error)
625 goto out;
626
627 if (!IS_ELF(*hdr)) {
628 error = ENOEXEC;
629 goto out;
630 }
631
632 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
633 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
634 link_elf_error(filename, "Unsupported file layout");
635 error = ENOEXEC;
636 goto out;
637 }
638 if (hdr->e_ident[EI_VERSION] != EV_CURRENT
639 || hdr->e_version != EV_CURRENT) {
640 link_elf_error(filename, "Unsupported file version");
641 error = ENOEXEC;
642 goto out;
643 }
644 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
645 error = ENOSYS;
646 goto out;
647 }
648 if (hdr->e_machine != ELF_TARG_MACH) {
649 link_elf_error(filename, "Unsupported machine");
650 error = ENOEXEC;
651 goto out;
652 }
653
654 /*
655 * We rely on the program header being in the first page. This is
656 * not strictly required by the ABI specification, but it seems to
657 * always true in practice. And, it simplifies things considerably.
658 */
659 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
660 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
661 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
662 link_elf_error(filename, "Unreadable program headers");
663
664 /*
665 * Scan the program header entries, and save key information.
666 *
667 * We rely on there being exactly two load segments, text and data,
668 * in that order.
669 */
670 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
671 phlimit = phdr + hdr->e_phnum;
672 nsegs = 0;
673 phdyn = NULL;
674 phphdr = NULL;
675 while (phdr < phlimit) {
676 switch (phdr->p_type) {
677
678 case PT_LOAD:
679 if (nsegs == MAXSEGS) {
680 link_elf_error(filename, "Too many sections");
681 error = ENOEXEC;
682 goto out;
683 }
684 /*
685 * XXX: We just trust they come in right order ??
686 */
687 segs[nsegs] = phdr;
688 ++nsegs;
689 break;
690
691 case PT_PHDR:
692 phphdr = phdr;
693 break;
694
695 case PT_DYNAMIC:
696 phdyn = phdr;
697 break;
698
699 case PT_INTERP:
700 error = ENOSYS;
701 goto out;
702 }
703
704 ++phdr;
705 }
706 if (phdyn == NULL) {
707 link_elf_error(filename, "Object is not dynamically-linked");
708 error = ENOEXEC;
709 goto out;
710 }
711 if (nsegs == 0) {
712 link_elf_error(filename, "No sections");
713 error = ENOEXEC;
714 goto out;
715 }
716
717 /*
718 * Allocate the entire address space of the object, to stake out our
719 * contiguous region, and to establish the base address for relocation.
720 */
721 base_offset = trunc_page(segs[0]->p_offset);
722 base_vaddr = trunc_page(segs[0]->p_vaddr);
723 base_vlimit = round_page(segs[nsegs - 1]->p_vaddr +
724 segs[nsegs - 1]->p_memsz);
725 mapsize = base_vlimit - base_vaddr;
726
727 lf = linker_make_file(filename, &link_elf_class);
728 if (!lf) {
729 error = ENOMEM;
730 goto out;
731 }
732
733 ef = (elf_file_t) lf;
734#ifdef SPARSE_MAPPING
735 ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
736 if (ef->object == NULL) {
737 error = ENOMEM;
738 goto out;
739 }
740 ef->address = (caddr_t) vm_map_min(kernel_map);
741 error = vm_map_find(kernel_map, ef->object, 0,
742 (vm_offset_t *) &ef->address,
743 mapsize, 1,
744 VM_PROT_ALL, VM_PROT_ALL, 0);
745 if (error) {
746 vm_object_deallocate(ef->object);
747 ef->object = 0;
748 goto out;
749 }
750#else
751 ef->address = malloc(mapsize, M_LINKER, M_WAITOK);
752 if (!ef->address) {
753 error = ENOMEM;
754 goto out;
755 }
756#endif
757 mapbase = ef->address;
758
759 /*
760 * Read the text and data sections and zero the bss.
761 */
762 for (i = 0; i < nsegs; i++) {
763 caddr_t segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
764 error = vn_rdwr(UIO_READ, nd.ni_vp,
765 segbase, segs[i]->p_filesz, segs[i]->p_offset,
766 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
767 &resid, td);
768 if (error) {
769 goto out;
770 }
771 bzero(segbase + segs[i]->p_filesz,
772 segs[i]->p_memsz - segs[i]->p_filesz);
773
774#ifdef SPARSE_MAPPING
775 /*
776 * Wire down the pages
777 */
778 error = vm_map_wire(kernel_map,
779 (vm_offset_t) segbase,
780 (vm_offset_t) segbase + segs[i]->p_memsz,
781 VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
782 if (error != KERN_SUCCESS) {
783 error = ENOMEM;
784 goto out;
785 }
786#endif
787 }
788
789#ifdef GPROF
790 /* Update profiling information with the new text segment. */
791 mtx_lock(&Giant);
792 kmupetext((uintfptr_t)(mapbase + segs[0]->p_vaddr - base_vaddr +
793 segs[0]->p_memsz));
794 mtx_unlock(&Giant);
795#endif
796
797 ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
798
799 lf->address = ef->address;
800 lf->size = mapsize;
801
802 error = parse_dynamic(ef);
803 if (error)
804 goto out;
805 link_elf_reloc_local(lf);
806
807 VOP_UNLOCK(nd.ni_vp, 0);
808 error = linker_load_dependencies(lf);
809 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
810 if (error)
811 goto out;
812#if 0 /* this will be more trouble than it's worth for now */
813 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
814 if (dp->d_tag != DT_NEEDED)
815 continue;
816 modname = ef->strtab + dp->d_un.d_val;
817 error = linker_load_module(modname, lf);
818 if (error)
819 goto out;
820 }
821#endif
822 error = relocate_file(ef);
823 if (error)
824 goto out;
825
826 /* Try and load the symbol table if it's present. (you can strip it!) */
827 nbytes = hdr->e_shnum * hdr->e_shentsize;
828 if (nbytes == 0 || hdr->e_shoff == 0)
829 goto nosyms;
830 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
831 if (shdr == NULL) {
832 error = ENOMEM;
833 goto out;
834 }
835 error = vn_rdwr(UIO_READ, nd.ni_vp,
836 (caddr_t)shdr, nbytes, hdr->e_shoff,
837 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
838 &resid, td);
839 if (error)
840 goto out;
841 symtabindex = -1;
842 symstrindex = -1;
843 for (i = 0; i < hdr->e_shnum; i++) {
844 if (shdr[i].sh_type == SHT_SYMTAB) {
845 symtabindex = i;
846 symstrindex = shdr[i].sh_link;
847 }
848 }
849 if (symtabindex < 0 || symstrindex < 0)
850 goto nosyms;
851
852 symcnt = shdr[symtabindex].sh_size;
853 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK);
854 strcnt = shdr[symstrindex].sh_size;
855 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK);
856
857 if (ef->symbase == NULL || ef->strbase == NULL) {
858 error = ENOMEM;
859 goto out;
860 }
861 error = vn_rdwr(UIO_READ, nd.ni_vp,
862 ef->symbase, symcnt, shdr[symtabindex].sh_offset,
863 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
864 &resid, td);
865 if (error)
866 goto out;
867 error = vn_rdwr(UIO_READ, nd.ni_vp,
868 ef->strbase, strcnt, shdr[symstrindex].sh_offset,
869 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
870 &resid, td);
871 if (error)
872 goto out;
873
874 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
875 ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
876 ef->ddbstrcnt = strcnt;
877 ef->ddbstrtab = ef->strbase;
878
879 error = link_elf_link_common_finish(lf);
880 if (error)
881 goto out;
882
883nosyms:
884
885 *result = lf;
886
887out:
888 if (error && lf)
889 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
890 if (shdr)
891 free(shdr, M_LINKER);
892 if (firstpage)
893 free(firstpage, M_LINKER);
894 VOP_UNLOCK(nd.ni_vp, 0);
895 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
896 VFS_UNLOCK_GIANT(vfslocked);
897
898 return error;
899}
900
901static void
902link_elf_unload_file(linker_file_t file)
903{
904 elf_file_t ef = (elf_file_t) file;
905
906#ifdef GDB
907 if (ef->gdb.l_ld) {
908 GDB_STATE(RT_DELETE);
909 free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER);
910 link_elf_delete_gdb(&ef->gdb);
911 GDB_STATE(RT_CONSISTENT);
912 }
913#endif
914
915 /* Notify MD code that a module is being unloaded. */
916 elf_cpu_unload_file(file);
917
918 if (ef->preloaded) {
919 link_elf_unload_preload(file);
920 return;
921 }
922
923#ifdef SPARSE_MAPPING
924 if (ef->object) {
925 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
926 (vm_offset_t) ef->address
927 + (ef->object->size << PAGE_SHIFT));
928 }
929#else
930 if (ef->address)
931 free(ef->address, M_LINKER);
932#endif
933 if (ef->symbase)
934 free(ef->symbase, M_LINKER);
935 if (ef->strbase)
936 free(ef->strbase, M_LINKER);
937 if (ef->ctftab)
938 free(ef->ctftab, M_LINKER);
939 if (ef->ctfoff)
940 free(ef->ctfoff, M_LINKER);
941 if (ef->typoff)
942 free(ef->typoff, M_LINKER);
943}
944
945static void
946link_elf_unload_preload(linker_file_t file)
947{
948 if (file->filename)
949 preload_delete_name(file->filename);
950}
951
952static const char *
953symbol_name(elf_file_t ef, Elf_Size r_info)
954{
955 const Elf_Sym *ref;
956
957 if (ELF_R_SYM(r_info)) {
958 ref = ef->symtab + ELF_R_SYM(r_info);
959 return ef->strtab + ref->st_name;
960 } else
961 return NULL;
962}
963
964static int
965relocate_file(elf_file_t ef)
966{
967 const Elf_Rel *rellim;
968 const Elf_Rel *rel;
969 const Elf_Rela *relalim;
970 const Elf_Rela *rela;
971 const char *symname;
972
973 /* Perform relocations without addend if there are any: */
974 rel = ef->rel;
975 if (rel) {
976 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
977 while (rel < rellim) {
978 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
979 elf_lookup)) {
980 symname = symbol_name(ef, rel->r_info);
981 printf("link_elf: symbol %s undefined\n", symname);
982 return ENOENT;
983 }
984 rel++;
985 }
986 }
987
988 /* Perform relocations with addend if there are any: */
989 rela = ef->rela;
990 if (rela) {
991 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
992 while (rela < relalim) {
993 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
994 elf_lookup)) {
995 symname = symbol_name(ef, rela->r_info);
996 printf("link_elf: symbol %s undefined\n", symname);
997 return ENOENT;
998 }
999 rela++;
1000 }
1001 }
1002
1003 /* Perform PLT relocations without addend if there are any: */
1004 rel = ef->pltrel;
1005 if (rel) {
1006 rellim = (const Elf_Rel *)((const char *)ef->pltrel + ef->pltrelsize);
1007 while (rel < rellim) {
1008 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
1009 elf_lookup)) {
1010 symname = symbol_name(ef, rel->r_info);
1011 printf("link_elf: symbol %s undefined\n", symname);
1012 return ENOENT;
1013 }
1014 rel++;
1015 }
1016 }
1017
1018 /* Perform relocations with addend if there are any: */
1019 rela = ef->pltrela;
1020 if (rela) {
1021 relalim = (const Elf_Rela *)((const char *)ef->pltrela + ef->pltrelasize);
1022 while (rela < relalim) {
1023 if (elf_reloc(&ef->lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
1024 elf_lookup)) {
1025 symname = symbol_name(ef, rela->r_info);
1026 printf("link_elf: symbol %s undefined\n", symname);
1027 return ENOENT;
1028 }
1029 rela++;
1030 }
1031 }
1032
1033 return 0;
1034}
1035
1036/*
1037 * Hash function for symbol table lookup. Don't even think about changing
1038 * this. It is specified by the System V ABI.
1039 */
1040static unsigned long
1041elf_hash(const char *name)
1042{
1043 const unsigned char *p = (const unsigned char *) name;
1044 unsigned long h = 0;
1045 unsigned long g;
1046
1047 while (*p != '\0') {
1048 h = (h << 4) + *p++;
1049 if ((g = h & 0xf0000000) != 0)
1050 h ^= g >> 24;
1051 h &= ~g;
1052 }
1053 return h;
1054}
1055
1056static int
1057link_elf_lookup_symbol(linker_file_t lf, const char* name, c_linker_sym_t* sym)
1058{
1059 elf_file_t ef = (elf_file_t) lf;
1060 unsigned long symnum;
1061 const Elf_Sym* symp;
1062 const char *strp;
1063 unsigned long hash;
1064 int i;
1065
1066 /* If we don't have a hash, bail. */
1067 if (ef->buckets == NULL || ef->nbuckets == 0) {
1068 printf("link_elf_lookup_symbol: missing symbol hash table\n");
1069 return ENOENT;
1070 }
1071
1072 /* First, search hashed global symbols */
1073 hash = elf_hash(name);
1074 symnum = ef->buckets[hash % ef->nbuckets];
1075
1076 while (symnum != STN_UNDEF) {
1077 if (symnum >= ef->nchains) {
1078 printf("link_elf_lookup_symbol: corrupt symbol table\n");
1079 return ENOENT;
1080 }
1081
1082 symp = ef->symtab + symnum;
1083 if (symp->st_name == 0) {
1084 printf("link_elf_lookup_symbol: corrupt symbol table\n");
1085 return ENOENT;
1086 }
1087
1088 strp = ef->strtab + symp->st_name;
1089
1090 if (strcmp(name, strp) == 0) {
1091 if (symp->st_shndx != SHN_UNDEF ||
1092 (symp->st_value != 0 &&
1093 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
1094 *sym = (c_linker_sym_t) symp;
1095 return 0;
1096 } else
1097 return ENOENT;
1098 }
1099
1100 symnum = ef->chains[symnum];
1101 }
1102
1103 /* If we have not found it, look at the full table (if loaded) */
1104 if (ef->symtab == ef->ddbsymtab)
1105 return ENOENT;
1106
1107 /* Exhaustive search */
1108 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1109 strp = ef->ddbstrtab + symp->st_name;
1110 if (strcmp(name, strp) == 0) {
1111 if (symp->st_shndx != SHN_UNDEF ||
1112 (symp->st_value != 0 &&
1113 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
1114 *sym = (c_linker_sym_t) symp;
1115 return 0;
1116 } else
1117 return ENOENT;
1118 }
1119 }
1120
1121 return ENOENT;
1122}
1123
1124static int
1125link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, linker_symval_t* symval)
1126{
1127 elf_file_t ef = (elf_file_t) lf;
1128 const Elf_Sym* es = (const Elf_Sym*) sym;
1129
1130 if (es >= ef->symtab && es < (ef->symtab + ef->nchains)) {
1131 symval->name = ef->strtab + es->st_name;
1132 symval->value = (caddr_t) ef->address + es->st_value;
1133 symval->size = es->st_size;
1134 return 0;
1135 }
1136 if (ef->symtab == ef->ddbsymtab)
1137 return ENOENT;
1138 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1139 symval->name = ef->ddbstrtab + es->st_name;
1140 symval->value = (caddr_t) ef->address + es->st_value;
1141 symval->size = es->st_size;
1142 return 0;
1143 }
1144 return ENOENT;
1145}
1146
1147static int
1148link_elf_search_symbol(linker_file_t lf, caddr_t value,
1149 c_linker_sym_t* sym, long* diffp)
1150{
1151 elf_file_t ef = (elf_file_t) lf;
1152 u_long off = (uintptr_t) (void *) value;
1153 u_long diff = off;
1154 u_long st_value;
1155 const Elf_Sym* es;
1156 const Elf_Sym* best = 0;
1157 int i;
1158
1159 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1160 if (es->st_name == 0)
1161 continue;
1162 st_value = es->st_value + (uintptr_t) (void *) ef->address;
1163 if (off >= st_value) {
1164 if (off - st_value < diff) {
1165 diff = off - st_value;
1166 best = es;
1167 if (diff == 0)
1168 break;
1169 } else if (off - st_value == diff) {
1170 best = es;
1171 }
1172 }
1173 }
1174 if (best == 0)
1175 *diffp = off;
1176 else
1177 *diffp = diff;
1178 *sym = (c_linker_sym_t) best;
1179
1180 return 0;
1181}
1182
1183/*
1184 * Look up a linker set on an ELF system.
1185 */
1186static int
1187link_elf_lookup_set(linker_file_t lf, const char *name,
1188 void ***startp, void ***stopp, int *countp)
1189{
1190 c_linker_sym_t sym;
1191 linker_symval_t symval;
1192 char *setsym;
1193 void **start, **stop;
1194 int len, error = 0, count;
1195
1196 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
1197 setsym = malloc(len, M_LINKER, M_WAITOK);
1198 if (setsym == NULL)
1199 return ENOMEM;
1200
1201 /* get address of first entry */
1202 snprintf(setsym, len, "%s%s", "__start_set_", name);
1203 error = link_elf_lookup_symbol(lf, setsym, &sym);
1204 if (error)
1205 goto out;
1206 link_elf_symbol_values(lf, sym, &symval);
1207 if (symval.value == 0) {
1208 error = ESRCH;
1209 goto out;
1210 }
1211 start = (void **)symval.value;
1212
1213 /* get address of last entry */
1214 snprintf(setsym, len, "%s%s", "__stop_set_", name);
1215 error = link_elf_lookup_symbol(lf, setsym, &sym);
1216 if (error)
1217 goto out;
1218 link_elf_symbol_values(lf, sym, &symval);
1219 if (symval.value == 0) {
1220 error = ESRCH;
1221 goto out;
1222 }
1223 stop = (void **)symval.value;
1224
1225 /* and the number of entries */
1226 count = stop - start;
1227
1228 /* and copy out */
1229 if (startp)
1230 *startp = start;
1231 if (stopp)
1232 *stopp = stop;
1233 if (countp)
1234 *countp = count;
1235
1236out:
1237 free(setsym, M_LINKER);
1238 return error;
1239}
1240
1241static int
1242link_elf_each_function_name(linker_file_t file,
1243 int (*callback)(const char *, void *), void *opaque) {
1244 elf_file_t ef = (elf_file_t)file;
1245 const Elf_Sym* symp;
1246 int i, error;
1247
1248 /* Exhaustive search */
1249 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1250 if (symp->st_value != 0 &&
1251 ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1252 error = callback(ef->ddbstrtab + symp->st_name, opaque);
1253 if (error)
1254 return (error);
1255 }
1256 }
1257 return (0);
1258}
1259
1260static int
1261link_elf_each_function_nameval(linker_file_t file,
1262 linker_function_nameval_callback_t callback, void *opaque)
1263{
1264 linker_symval_t symval;
1265 elf_file_t ef = (elf_file_t)file;
1266 const Elf_Sym* symp;
1267 int i, error;
1268
1269 /* Exhaustive search */
1270 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1271 if (symp->st_value != 0 &&
1272 ELF_ST_TYPE(symp->st_info) == STT_FUNC) {
1273 error = link_elf_symbol_values(file, (c_linker_sym_t) symp, &symval);
1274 if (error)
1275 return (error);
1276 error = callback(file, i, &symval, opaque);
1277 if (error)
1278 return (error);
1279 }
1280 }
1281 return (0);
1282}
1283
1284#ifdef __ia64__
1285/*
1286 * Each KLD has its own GP. The GP value for each load module is given by
1287 * DT_PLTGOT on ia64. We need GP to construct function descriptors, but
1288 * don't have direct access to the ELF file structure. The link_elf_get_gp()
1289 * function returns the GP given a pointer to a generic linker file struct.
1290 */
1291Elf_Addr
1292link_elf_get_gp(linker_file_t lf)
1293{
1294 elf_file_t ef = (elf_file_t)lf;
1295 return (Elf_Addr)ef->got;
1296}
1297#endif
1298
1299const Elf_Sym *
1300elf_get_sym(linker_file_t lf, Elf_Size symidx)
1301{
1302 elf_file_t ef = (elf_file_t)lf;
1303
1304 if (symidx >= ef->nchains)
1305 return (NULL);
1306 return (ef->symtab + symidx);
1307}
1308
1309const char *
1310elf_get_symname(linker_file_t lf, Elf_Size symidx)
1311{
1312 elf_file_t ef = (elf_file_t)lf;
1313 const Elf_Sym *sym;
1314
1315 if (symidx >= ef->nchains)
1316 return (NULL);
1317 sym = ef->symtab + symidx;
1318 return (ef->strtab + sym->st_name);
1319}
1320
1321/*
1322 * Symbol lookup function that can be used when the symbol index is known (ie
1323 * in relocations). It uses the symbol index instead of doing a fully fledged
1324 * hash table based lookup when such is valid. For example for local symbols.
1325 * This is not only more efficient, it's also more correct. It's not always
1326 * the case that the symbol can be found through the hash table.
1327 */
1328static Elf_Addr
1329elf_lookup(linker_file_t lf, Elf_Size symidx, int deps)
1330{
1331 elf_file_t ef = (elf_file_t)lf;
1332 const Elf_Sym *sym;
1333 const char *symbol;
1334
1335 /* Don't even try to lookup the symbol if the index is bogus. */
1336 if (symidx >= ef->nchains)
1337 return (0);
1338
1339 sym = ef->symtab + symidx;
1340
1341 /*
1342 * Don't do a full lookup when the symbol is local. It may even
1343 * fail because it may not be found through the hash table.
1344 */
1345 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
1346 /* Force lookup failure when we have an insanity. */
1347 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0)
1348 return (0);
1349 return ((Elf_Addr)ef->address + sym->st_value);
1350 }
1351
1352 /*
1353 * XXX we can avoid doing a hash table based lookup for global
1354 * symbols as well. This however is not always valid, so we'll
1355 * just do it the hard way for now. Performance tweaks can
1356 * always be added.
1357 */
1358
1359 symbol = ef->strtab + sym->st_name;
1360
1361 /* Force a lookup failure if the symbol name is bogus. */
1362 if (*symbol == 0)
1363 return (0);
1364
1365 return ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1366}
1367
1368static void
1369link_elf_reloc_local(linker_file_t lf)
1370{
1371 const Elf_Rel *rellim;
1372 const Elf_Rel *rel;
1373 const Elf_Rela *relalim;
1374 const Elf_Rela *rela;
1375 elf_file_t ef = (elf_file_t)lf;
1376
1377 /* Perform relocations without addend if there are any: */
1378 if ((rel = ef->rel) != NULL) {
1379 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
1380 while (rel < rellim) {
1381 elf_reloc_local(lf, (Elf_Addr)ef->address, rel, ELF_RELOC_REL,
1382 elf_lookup);
1383 rel++;
1384 }
1385 }
1386
1387 /* Perform relocations with addend if there are any: */
1388 if ((rela = ef->rela) != NULL) {
1389 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
1390 while (rela < relalim) {
1391 elf_reloc_local(lf, (Elf_Addr)ef->address, rela, ELF_RELOC_RELA,
1392 elf_lookup);
1393 rela++;
1394 }
1395 }
1396}
1397
1398static long
1399link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1400{
1401 elf_file_t ef = (elf_file_t)lf;
1402
1403 *symtab = ef->ddbsymtab;
1404
1405 if (*symtab == NULL)
1406 return (0);
1407
1408 return (ef->ddbsymcnt);
1409}
1410
1411static long
1412link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1413{
1414 elf_file_t ef = (elf_file_t)lf;
1415
1416 *strtab = ef->ddbstrtab;
1417
1418 if (*strtab == NULL)
1419 return (0);
1420
1421 return (ef->ddbstrcnt);
1422}