2 * Copyright (c) 1998 Doug Rabson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
26 * $FreeBSD: src/sys/kern/link_elf.c,v 1.24 1999/12/24 15:33:36 bde Exp $
27 * $DragonFly: src/sys/kern/link_elf.c,v 1.15 2004/11/12 00:09:23 dillon Exp $
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/systm.h>
33 #include <sys/malloc.h>
35 #include <sys/nlookup.h>
36 #include <sys/fcntl.h>
37 #include <sys/vnode.h>
38 #include <sys/linker.h>
39 #include <machine/elf.h>
42 #include <vm/vm_param.h>
43 #include <vm/vm_zone.h>
46 #include <vm/vm_object.h>
47 #include <vm/vm_kern.h>
48 #include <vm/vm_extern.h>
51 #include <vm/vm_map.h>
53 static int link_elf_load_module(const char*, linker_file_t*);
54 static int link_elf_load_file(const char*, linker_file_t*);
55 static int link_elf_lookup_symbol(linker_file_t, const char*,
57 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t*);
58 static int link_elf_search_symbol(linker_file_t, caddr_t value,
59 c_linker_sym_t* sym, long* diffp);
61 static void link_elf_unload_file(linker_file_t);
62 static void link_elf_unload_module(linker_file_t);
63 static int link_elf_lookup_set(linker_file_t, const char *,
64 void ***, void ***, int *);
67 static struct linker_class_ops link_elf_class_ops = {
71 static struct linker_file_ops link_elf_file_ops = {
72 link_elf_lookup_symbol,
73 link_elf_symbol_values,
74 link_elf_search_symbol,
79 static struct linker_file_ops link_elf_module_ops = {
80 link_elf_lookup_symbol,
81 link_elf_symbol_values,
82 link_elf_search_symbol,
83 link_elf_unload_module,
86 typedef struct elf_file {
87 caddr_t address; /* Relocation address */
89 vm_object_t object; /* VM object to hold file pages */
91 const Elf_Dyn* dynamic; /* Symbol table etc. */
92 Elf_Off nbuckets; /* DT_HASH info */
94 const Elf_Off* buckets;
95 const Elf_Off* chains;
97 caddr_t strtab; /* DT_STRTAB */
98 int strsz; /* DT_STRSZ */
99 const Elf_Sym* symtab; /* DT_SYMTAB */
100 Elf_Addr* got; /* DT_PLTGOT */
101 const Elf_Rel* pltrel; /* DT_JMPREL */
102 int pltrelsize; /* DT_PLTRELSZ */
103 const Elf_Rela* pltrela; /* DT_JMPREL */
104 int pltrelasize; /* DT_PLTRELSZ */
105 const Elf_Rel* rel; /* DT_REL */
106 int relsize; /* DT_RELSZ */
107 const Elf_Rela* rela; /* DT_RELA */
108 int relasize; /* DT_RELASZ */
110 const Elf_Sym* ddbsymtab; /* The symbol table we are using */
111 long ddbsymcnt; /* Number of symbols */
112 caddr_t ddbstrtab; /* String table */
113 long ddbstrcnt; /* number of bytes in string table */
114 caddr_t symbase; /* malloc'ed symbold base */
115 caddr_t strbase; /* malloc'ed string base */
118 static int parse_dynamic(linker_file_t lf);
119 static int load_dependancies(linker_file_t lf);
120 static int relocate_file(linker_file_t lf);
121 static int parse_module_symbols(linker_file_t lf);
124 * The kernel symbol table starts here.
126 extern struct _dynamic _DYNAMIC;
129 link_elf_init(void* arg)
132 caddr_t modptr, baseptr, sizeptr;
136 #if ELF_TARG_CLASS == ELFCLASS32
137 linker_add_class("elf32", NULL, &link_elf_class_ops);
139 linker_add_class("elf64", NULL, &link_elf_class_ops);
142 dp = (Elf_Dyn*) &_DYNAMIC;
144 ef = malloc(sizeof(struct elf_file), M_LINKER, M_NOWAIT);
146 panic("link_elf_init: Can't create linker structures for kernel");
147 bzero(ef, sizeof(*ef));
150 #ifdef SPARSE_MAPPING
155 modptr = preload_search_by_type("elf kernel");
157 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
160 linker_kernel_file = linker_make_file(modname, ef, &link_elf_file_ops);
161 if (linker_kernel_file == NULL)
162 panic("link_elf_init: Can't create linker structures for kernel");
163 parse_dynamic(linker_kernel_file);
164 linker_kernel_file->address = (caddr_t) KERNBASE;
165 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
169 baseptr = preload_search_info(modptr, MODINFO_ADDR);
171 linker_kernel_file->address = *(caddr_t *)baseptr;
172 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
174 linker_kernel_file->size = *(size_t *)sizeptr;
176 (void)parse_module_symbols(linker_kernel_file);
177 linker_current_file = linker_kernel_file;
178 linker_kernel_file->flags |= LINKER_FILE_LINKED;
182 SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, 0);
185 parse_module_symbols(linker_file_t lf)
187 elf_file_t ef = lf->priv;
189 caddr_t ssym, esym, base;
195 if (ef->modptr == NULL)
197 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_SSYM);
200 ssym = *(caddr_t *)pointer;
201 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_ESYM);
204 esym = *(caddr_t *)pointer;
208 symcnt = *(long *)base;
209 base += sizeof(long);
210 symtab = (Elf_Sym *)base;
211 base += roundup(symcnt, sizeof(long));
213 if (base > esym || base < ssym) {
214 printf("Symbols are corrupt!\n");
218 strcnt = *(long *)base;
219 base += sizeof(long);
221 base += roundup(strcnt, sizeof(long));
223 if (base > esym || base < ssym) {
224 printf("Symbols are corrupt!\n");
228 ef->ddbsymtab = symtab;
229 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
230 ef->ddbstrtab = strtab;
231 ef->ddbstrcnt = strcnt;
237 parse_dynamic(linker_file_t lf)
239 elf_file_t ef = lf->priv;
241 int plttype = DT_REL;
243 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
247 /* From src/libexec/rtld-elf/rtld.c */
248 const Elf_Off *hashtab = (const Elf_Off *)
249 (ef->address + dp->d_un.d_ptr);
250 ef->nbuckets = hashtab[0];
251 ef->nchains = hashtab[1];
252 ef->buckets = hashtab + 2;
253 ef->chains = ef->buckets + ef->nbuckets;
257 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
260 ef->strsz = dp->d_un.d_val;
263 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
266 if (dp->d_un.d_val != sizeof(Elf_Sym))
270 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
273 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
276 ef->relsize = dp->d_un.d_val;
279 if (dp->d_un.d_val != sizeof(Elf_Rel))
283 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
286 ef->pltrelsize = dp->d_un.d_val;
289 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
292 ef->relasize = dp->d_un.d_val;
295 if (dp->d_un.d_val != sizeof(Elf_Rela))
299 plttype = dp->d_un.d_val;
300 if (plttype != DT_REL && plttype != DT_RELA)
306 if (plttype == DT_RELA) {
307 ef->pltrela = (const Elf_Rela *) ef->pltrel;
309 ef->pltrelasize = ef->pltrelsize;
313 ef->ddbsymtab = ef->symtab;
314 ef->ddbsymcnt = ef->nchains;
315 ef->ddbstrtab = ef->strtab;
316 ef->ddbstrcnt = ef->strsz;
322 link_elf_error(const char *s)
324 printf("kldload: %s\n", s);
328 link_elf_load_module(const char *filename, linker_file_t *result)
330 caddr_t modptr, baseptr, sizeptr, dynptr;
338 * Look to see if we have the module preloaded.
340 modptr = preload_search_by_name(filename);
342 return (link_elf_load_file(filename, result));
344 /* It's preloaded, check we can handle it and collect information */
345 type = (char *)preload_search_info(modptr, MODINFO_TYPE);
346 baseptr = preload_search_info(modptr, MODINFO_ADDR);
347 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
348 dynptr = preload_search_info(modptr, MODINFO_METADATA|MODINFOMD_DYNAMIC);
349 if (type == NULL || strcmp(type, "elf module") != 0)
351 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
354 ef = malloc(sizeof(struct elf_file), M_LINKER, M_WAITOK);
357 bzero(ef, sizeof(*ef));
359 ef->address = *(caddr_t *)baseptr;
360 #ifdef SPARSE_MAPPING
363 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
364 ef->dynamic = (Elf_Dyn *)dp;
365 lf = linker_make_file(filename, ef, &link_elf_module_ops);
370 lf->address = ef->address;
371 lf->size = *(size_t *)sizeptr;
373 error = parse_dynamic(lf);
375 linker_file_unload(lf);
378 error = load_dependancies(lf);
380 linker_file_unload(lf);
383 error = relocate_file(lf);
385 linker_file_unload(lf);
388 (void)parse_module_symbols(lf);
389 lf->flags |= LINKER_FILE_LINKED;
395 link_elf_load_file(const char* filename, linker_file_t* result)
397 struct nlookupdata nd;
398 struct thread *td = curthread; /* XXX */
399 struct proc *p = td->td_proc;
414 Elf_Addr base_vlimit;
427 if (p->p_ucred == NULL) {
428 printf("link_elf_load_file: cannot load '%s' from filesystem"
429 " this early\n", filename);
434 pathname = linker_search_path(filename);
435 if (pathname == NULL)
438 error = nlookup_init(&nd, pathname, UIO_SYSSPACE, NLC_FOLLOW|NLC_LOCKVP);
440 error = vn_open(&nd, NULL, FREAD, 0);
441 free(pathname, M_LINKER);
447 nd.nl_open_vp = NULL;
451 * Read the elf header from the file.
453 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK);
454 if (firstpage == NULL) {
458 hdr = (Elf_Ehdr *)firstpage;
459 error = vn_rdwr(UIO_READ, vp, firstpage, PAGE_SIZE, 0,
460 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
461 nbytes = PAGE_SIZE - resid;
470 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
471 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
472 link_elf_error("Unsupported file layout");
476 if (hdr->e_ident[EI_VERSION] != EV_CURRENT
477 || hdr->e_version != EV_CURRENT) {
478 link_elf_error("Unsupported file version");
482 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
483 link_elf_error("Unsupported file type");
487 if (hdr->e_machine != ELF_TARG_MACH) {
488 link_elf_error("Unsupported machine");
494 * We rely on the program header being in the first page. This is
495 * not strictly required by the ABI specification, but it seems to
496 * always true in practice. And, it simplifies things considerably.
498 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
499 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
500 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
501 link_elf_error("Unreadable program headers");
504 * Scan the program header entries, and save key information.
506 * We rely on there being exactly two load segments, text and data,
509 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
510 phlimit = phdr + hdr->e_phnum;
514 while (phdr < phlimit) {
515 switch (phdr->p_type) {
519 link_elf_error("Too many sections");
539 link_elf_error("Object is not dynamically-linked");
545 * Allocate the entire address space of the object, to stake out our
546 * contiguous region, and to establish the base address for relocation.
548 base_offset = trunc_page(segs[0]->p_offset);
549 base_vaddr = trunc_page(segs[0]->p_vaddr);
550 base_vlimit = round_page(segs[1]->p_vaddr + segs[1]->p_memsz);
551 mapsize = base_vlimit - base_vaddr;
553 ef = malloc(sizeof(struct elf_file), M_LINKER, M_WAITOK);
554 bzero(ef, sizeof(*ef));
555 #ifdef SPARSE_MAPPING
556 ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
557 if (ef->object == NULL) {
562 vm_object_reference(ef->object);
563 ef->address = (caddr_t) vm_map_min(kernel_map);
564 error = vm_map_find(kernel_map, ef->object, 0,
565 (vm_offset_t *) &ef->address,
567 VM_PROT_ALL, VM_PROT_ALL, 0);
569 vm_object_deallocate(ef->object);
574 ef->address = malloc(mapsize, M_LINKER, M_WAITOK);
576 mapbase = ef->address;
579 * Read the text and data sections and zero the bss.
581 for (i = 0; i < 2; i++) {
582 caddr_t segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
583 error = vn_rdwr(UIO_READ, vp,
584 segbase, segs[i]->p_filesz, segs[i]->p_offset,
585 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
587 #ifdef SPARSE_MAPPING
588 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
589 (vm_offset_t) ef->address
590 + (ef->object->size << PAGE_SHIFT));
591 vm_object_deallocate(ef->object);
593 free(ef->address, M_LINKER);
598 bzero(segbase + segs[i]->p_filesz,
599 segs[i]->p_memsz - segs[i]->p_filesz);
601 #ifdef SPARSE_MAPPING
603 * Wire down the pages
605 vm_map_wire(kernel_map,
606 (vm_offset_t) segbase,
607 (vm_offset_t) segbase + segs[i]->p_memsz,
612 ef->dynamic = (const Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
614 lf = linker_make_file(filename, ef, &link_elf_file_ops);
616 #ifdef SPARSE_MAPPING
617 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
618 (vm_offset_t) ef->address
619 + (ef->object->size << PAGE_SHIFT));
620 vm_object_deallocate(ef->object);
622 free(ef->address, M_LINKER);
628 lf->address = ef->address;
631 error = parse_dynamic(lf);
634 error = load_dependancies(lf);
637 error = relocate_file(lf);
641 /* Try and load the symbol table if it's present. (you can strip it!) */
642 nbytes = hdr->e_shnum * hdr->e_shentsize;
643 if (nbytes == 0 || hdr->e_shoff == 0)
645 shdr = malloc(nbytes, M_LINKER, M_WAITOK);
651 error = vn_rdwr(UIO_READ, vp,
652 (caddr_t)shdr, nbytes, hdr->e_shoff,
653 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
658 for (i = 0; i < hdr->e_shnum; i++) {
659 if (shdr[i].sh_type == SHT_SYMTAB) {
661 symstrindex = shdr[i].sh_link;
664 if (symtabindex < 0 || symstrindex < 0)
667 symcnt = shdr[symtabindex].sh_size;
668 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK);
669 strcnt = shdr[symstrindex].sh_size;
670 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK);
672 if (ef->symbase == NULL || ef->strbase == NULL) {
676 error = vn_rdwr(UIO_READ, vp,
677 ef->symbase, symcnt, shdr[symtabindex].sh_offset,
678 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
681 error = vn_rdwr(UIO_READ, vp,
682 ef->strbase, strcnt, shdr[symstrindex].sh_offset,
683 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
687 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
688 ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
689 ef->ddbstrcnt = strcnt;
690 ef->ddbstrtab = ef->strbase;
692 lf->flags |= LINKER_FILE_LINKED;
700 linker_file_unload(lf);
702 free(shdr, M_LINKER);
704 free(firstpage, M_LINKER);
705 VOP_UNLOCK(vp, 0, td);
706 vn_close(vp, FREAD, td);
712 link_elf_unload_file(linker_file_t file)
714 elf_file_t ef = file->priv;
717 #ifdef SPARSE_MAPPING
719 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
720 (vm_offset_t) ef->address
721 + (ef->object->size << PAGE_SHIFT));
722 vm_object_deallocate(ef->object);
726 free(ef->address, M_LINKER);
729 free(ef->symbase, M_LINKER);
731 free(ef->strbase, M_LINKER);
737 link_elf_unload_module(linker_file_t file)
739 elf_file_t ef = file->priv;
744 preload_delete_name(file->filename);
748 load_dependancies(linker_file_t lf)
750 elf_file_t ef = lf->priv;
757 * All files are dependant on /kernel.
759 if (linker_kernel_file) {
760 linker_kernel_file->refs++;
761 linker_file_add_dependancy(lf, linker_kernel_file);
764 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
765 if (dp->d_tag == DT_NEEDED) {
766 name = ef->strtab + dp->d_un.d_val;
768 error = linker_load_file(name, &lfdep);
771 error = linker_file_add_dependancy(lf, lfdep);
782 symbol_name(elf_file_t ef, Elf_Word r_info)
786 if (ELF_R_SYM(r_info)) {
787 ref = ef->symtab + ELF_R_SYM(r_info);
788 return ef->strtab + ref->st_name;
794 relocate_file(linker_file_t lf)
796 elf_file_t ef = lf->priv;
797 const Elf_Rel *rellim;
799 const Elf_Rela *relalim;
800 const Elf_Rela *rela;
803 /* Perform relocations without addend if there are any: */
806 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
807 while (rel < rellim) {
808 symname = symbol_name(ef, rel->r_info);
809 if (elf_reloc(lf, rel, ELF_RELOC_REL, symname)) {
810 printf("link_elf: symbol %s undefined\n", symname);
817 /* Perform relocations with addend if there are any: */
820 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
821 while (rela < relalim) {
822 symname = symbol_name(ef, rela->r_info);
823 if (elf_reloc(lf, rela, ELF_RELOC_RELA, symname)) {
824 printf("link_elf: symbol %s undefined\n", symname);
831 /* Perform PLT relocations without addend if there are any: */
834 rellim = (const Elf_Rel *)((const char *)ef->pltrel + ef->pltrelsize);
835 while (rel < rellim) {
836 symname = symbol_name(ef, rel->r_info);
837 if (elf_reloc(lf, rel, ELF_RELOC_REL, symname)) {
838 printf("link_elf: symbol %s undefined\n", symname);
845 /* Perform relocations with addend if there are any: */
848 relalim = (const Elf_Rela *)((const char *)ef->pltrela + ef->pltrelasize);
849 while (rela < relalim) {
850 symname = symbol_name(ef, rela->r_info);
851 if (elf_reloc(lf, rela, ELF_RELOC_RELA, symname)) {
852 printf("link_elf: symbol %s undefined\n", symname);
863 * Hash function for symbol table lookup. Don't even think about changing
864 * this. It is specified by the System V ABI.
867 elf_hash(const char *name)
869 const unsigned char *p = (const unsigned char *) name;
875 if ((g = h & 0xf0000000) != 0)
883 link_elf_lookup_symbol(linker_file_t lf, const char* name, c_linker_sym_t* sym)
885 elf_file_t ef = lf->priv;
886 unsigned long symnum;
892 /* First, search hashed global symbols */
893 hash = elf_hash(name);
894 symnum = ef->buckets[hash % ef->nbuckets];
896 while (symnum != STN_UNDEF) {
897 if (symnum >= ef->nchains) {
898 printf("link_elf_lookup_symbol: corrupt symbol table\n");
902 symp = ef->symtab + symnum;
903 if (symp->st_name == 0) {
904 printf("link_elf_lookup_symbol: corrupt symbol table\n");
908 strp = ef->strtab + symp->st_name;
910 if (strcmp(name, strp) == 0) {
911 if (symp->st_shndx != SHN_UNDEF ||
912 (symp->st_value != 0 &&
913 ELF_ST_TYPE(symp->st_info) == STT_FUNC)
915 *sym = (c_linker_sym_t) symp;
922 symnum = ef->chains[symnum];
925 /* If we have not found it, look at the full table (if loaded) */
926 if (ef->symtab == ef->ddbsymtab)
929 /* Exhaustive search */
930 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
931 strp = ef->ddbstrtab + symp->st_name;
932 if (strcmp(name, strp) == 0) {
933 if (symp->st_shndx != SHN_UNDEF ||
934 (symp->st_value != 0 &&
935 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
936 *sym = (c_linker_sym_t) symp;
947 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, linker_symval_t* symval)
949 elf_file_t ef = lf->priv;
950 const Elf_Sym* es = (const Elf_Sym*) sym;
952 if (es >= ef->symtab && ((es - ef->symtab) < ef->nchains)) {
953 symval->name = ef->strtab + es->st_name;
954 symval->value = (caddr_t) ef->address + es->st_value;
955 symval->size = es->st_size;
958 if (ef->symtab == ef->ddbsymtab)
960 if (es >= ef->ddbsymtab && ((es - ef->ddbsymtab) < ef->ddbsymcnt)) {
961 symval->name = ef->ddbstrtab + es->st_name;
962 symval->value = (caddr_t) ef->address + es->st_value;
963 symval->size = es->st_size;
970 link_elf_search_symbol(linker_file_t lf, caddr_t value,
971 c_linker_sym_t* sym, long* diffp)
973 elf_file_t ef = lf->priv;
974 u_long off = (uintptr_t) (void *) value;
978 const Elf_Sym* best = 0;
981 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
982 if (es->st_name == 0)
984 st_value = es->st_value + (uintptr_t) (void *) ef->address;
985 if (off >= st_value) {
986 if (off - st_value < diff) {
987 diff = off - st_value;
991 } else if (off - st_value == diff) {
1000 *sym = (c_linker_sym_t) best;
1006 * Look up a linker set on an ELF system.
1009 link_elf_lookup_set(linker_file_t lf, const char *name,
1010 void ***startp, void ***stopp, int *countp)
1013 linker_symval_t symval;
1015 void **start, **stop;
1016 int len, error = 0, count;
1018 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
1019 setsym = malloc(len, M_LINKER, M_WAITOK);
1023 /* get address of first entry */
1024 snprintf(setsym, len, "%s%s", "__start_set_", name);
1025 error = link_elf_lookup_symbol(lf, setsym, &sym);
1028 link_elf_symbol_values(lf, sym, &symval);
1029 if (symval.value == 0) {
1033 start = (void **)symval.value;
1035 /* get address of last entry */
1036 snprintf(setsym, len, "%s%s", "__stop_set_", name);
1037 error = link_elf_lookup_symbol(lf, setsym, &sym);
1040 link_elf_symbol_values(lf, sym, &symval);
1041 if (symval.value == 0) {
1045 stop = (void **)symval.value;
1047 /* and the number of entries */
1048 count = stop - start;
1059 free(setsym, M_LINKER);