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 1.16 2005/03/03 19:50:33 hsu 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 *);
66 static struct linker_class_ops link_elf_class_ops = {
70 static struct linker_file_ops link_elf_file_ops = {
71 link_elf_lookup_symbol,
72 link_elf_symbol_values,
73 link_elf_search_symbol,
78 static struct linker_file_ops link_elf_module_ops = {
79 link_elf_lookup_symbol,
80 link_elf_symbol_values,
81 link_elf_search_symbol,
82 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 | M_ZERO);
146 panic("link_elf_init: Can't create linker structures for kernel");
149 #ifdef SPARSE_MAPPING
154 modptr = preload_search_by_type("elf kernel");
156 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
159 linker_kernel_file = linker_make_file(modname, ef, &link_elf_file_ops);
160 if (linker_kernel_file == NULL)
161 panic("link_elf_init: Can't create linker structures for kernel");
162 parse_dynamic(linker_kernel_file);
163 linker_kernel_file->address = (caddr_t) KERNBASE;
164 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
168 baseptr = preload_search_info(modptr, MODINFO_ADDR);
170 linker_kernel_file->address = *(caddr_t *)baseptr;
171 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
173 linker_kernel_file->size = *(size_t *)sizeptr;
175 parse_module_symbols(linker_kernel_file);
176 linker_current_file = linker_kernel_file;
177 linker_kernel_file->flags |= LINKER_FILE_LINKED;
181 SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_SECOND, link_elf_init, 0);
184 parse_module_symbols(linker_file_t lf)
186 elf_file_t ef = lf->priv;
188 caddr_t ssym, esym, base;
194 if (ef->modptr == NULL)
196 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_SSYM);
199 ssym = *(caddr_t *)pointer;
200 pointer = preload_search_info(ef->modptr, MODINFO_METADATA|MODINFOMD_ESYM);
203 esym = *(caddr_t *)pointer;
207 symcnt = *(long *)base;
208 base += sizeof(long);
209 symtab = (Elf_Sym *)base;
210 base += roundup(symcnt, sizeof(long));
212 if (base > esym || base < ssym) {
213 printf("Symbols are corrupt!\n");
217 strcnt = *(long *)base;
218 base += sizeof(long);
220 base += roundup(strcnt, sizeof(long));
222 if (base > esym || base < ssym) {
223 printf("Symbols are corrupt!\n");
227 ef->ddbsymtab = symtab;
228 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
229 ef->ddbstrtab = strtab;
230 ef->ddbstrcnt = strcnt;
236 parse_dynamic(linker_file_t lf)
238 elf_file_t ef = lf->priv;
240 int plttype = DT_REL;
242 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
246 /* From src/libexec/rtld-elf/rtld.c */
247 const Elf_Off *hashtab = (const Elf_Off *)
248 (ef->address + dp->d_un.d_ptr);
249 ef->nbuckets = hashtab[0];
250 ef->nchains = hashtab[1];
251 ef->buckets = hashtab + 2;
252 ef->chains = ef->buckets + ef->nbuckets;
256 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
259 ef->strsz = dp->d_un.d_val;
262 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
265 if (dp->d_un.d_val != sizeof(Elf_Sym))
269 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
272 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
275 ef->relsize = dp->d_un.d_val;
278 if (dp->d_un.d_val != sizeof(Elf_Rel))
282 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
285 ef->pltrelsize = dp->d_un.d_val;
288 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
291 ef->relasize = dp->d_un.d_val;
294 if (dp->d_un.d_val != sizeof(Elf_Rela))
298 plttype = dp->d_un.d_val;
299 if (plttype != DT_REL && plttype != DT_RELA)
305 if (plttype == DT_RELA) {
306 ef->pltrela = (const Elf_Rela *) ef->pltrel;
308 ef->pltrelasize = ef->pltrelsize;
312 ef->ddbsymtab = ef->symtab;
313 ef->ddbsymcnt = ef->nchains;
314 ef->ddbstrtab = ef->strtab;
315 ef->ddbstrcnt = ef->strsz;
321 link_elf_error(const char *s)
323 printf("kldload: %s\n", s);
327 link_elf_load_module(const char *filename, linker_file_t *result)
329 caddr_t modptr, baseptr, sizeptr, dynptr;
337 * Look to see if we have the module preloaded.
339 modptr = preload_search_by_name(filename);
341 return (link_elf_load_file(filename, result));
343 /* It's preloaded, check we can handle it and collect information */
344 type = (char *)preload_search_info(modptr, MODINFO_TYPE);
345 baseptr = preload_search_info(modptr, MODINFO_ADDR);
346 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
347 dynptr = preload_search_info(modptr, MODINFO_METADATA|MODINFOMD_DYNAMIC);
348 if (type == NULL || strcmp(type, "elf module") != 0)
350 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
353 ef = malloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
357 ef->address = *(caddr_t *)baseptr;
358 #ifdef SPARSE_MAPPING
361 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
362 ef->dynamic = (Elf_Dyn *)dp;
363 lf = linker_make_file(filename, ef, &link_elf_module_ops);
368 lf->address = ef->address;
369 lf->size = *(size_t *)sizeptr;
371 error = parse_dynamic(lf);
373 linker_file_unload(lf);
376 error = load_dependancies(lf);
378 linker_file_unload(lf);
381 error = relocate_file(lf);
383 linker_file_unload(lf);
386 parse_module_symbols(lf);
387 lf->flags |= LINKER_FILE_LINKED;
393 link_elf_load_file(const char* filename, linker_file_t* result)
395 struct nlookupdata nd;
396 struct thread *td = curthread; /* XXX */
397 struct proc *p = td->td_proc;
412 Elf_Addr base_vlimit;
425 if (p->p_ucred == NULL) {
426 printf("link_elf_load_file: cannot load '%s' from filesystem"
427 " this early\n", filename);
432 pathname = linker_search_path(filename);
433 if (pathname == NULL)
436 error = nlookup_init(&nd, pathname, UIO_SYSSPACE, NLC_FOLLOW|NLC_LOCKVP);
438 error = vn_open(&nd, NULL, FREAD, 0);
439 free(pathname, M_LINKER);
445 nd.nl_open_vp = NULL;
449 * Read the elf header from the file.
451 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK);
452 if (firstpage == NULL) {
456 hdr = (Elf_Ehdr *)firstpage;
457 error = vn_rdwr(UIO_READ, vp, firstpage, PAGE_SIZE, 0,
458 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
459 nbytes = PAGE_SIZE - resid;
468 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
469 || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
470 link_elf_error("Unsupported file layout");
474 if (hdr->e_ident[EI_VERSION] != EV_CURRENT
475 || hdr->e_version != EV_CURRENT) {
476 link_elf_error("Unsupported file version");
480 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
481 link_elf_error("Unsupported file type");
485 if (hdr->e_machine != ELF_TARG_MACH) {
486 link_elf_error("Unsupported machine");
492 * We rely on the program header being in the first page. This is
493 * not strictly required by the ABI specification, but it seems to
494 * always true in practice. And, it simplifies things considerably.
496 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
497 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
498 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
499 link_elf_error("Unreadable program headers");
502 * Scan the program header entries, and save key information.
504 * We rely on there being exactly two load segments, text and data,
507 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
508 phlimit = phdr + hdr->e_phnum;
512 while (phdr < phlimit) {
513 switch (phdr->p_type) {
517 link_elf_error("Too many sections");
537 link_elf_error("Object is not dynamically-linked");
543 * Allocate the entire address space of the object, to stake out our
544 * contiguous region, and to establish the base address for relocation.
546 base_offset = trunc_page(segs[0]->p_offset);
547 base_vaddr = trunc_page(segs[0]->p_vaddr);
548 base_vlimit = round_page(segs[1]->p_vaddr + segs[1]->p_memsz);
549 mapsize = base_vlimit - base_vaddr;
551 ef = malloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
552 #ifdef SPARSE_MAPPING
553 ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
554 if (ef->object == NULL) {
559 vm_object_reference(ef->object);
560 ef->address = (caddr_t) vm_map_min(kernel_map);
561 error = vm_map_find(kernel_map, ef->object, 0,
562 (vm_offset_t *) &ef->address,
564 VM_PROT_ALL, VM_PROT_ALL, 0);
566 vm_object_deallocate(ef->object);
571 ef->address = malloc(mapsize, M_LINKER, M_WAITOK);
573 mapbase = ef->address;
576 * Read the text and data sections and zero the bss.
578 for (i = 0; i < 2; i++) {
579 caddr_t segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
580 error = vn_rdwr(UIO_READ, vp,
581 segbase, segs[i]->p_filesz, segs[i]->p_offset,
582 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
584 #ifdef SPARSE_MAPPING
585 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
586 (vm_offset_t) ef->address
587 + (ef->object->size << PAGE_SHIFT));
588 vm_object_deallocate(ef->object);
590 free(ef->address, M_LINKER);
595 bzero(segbase + segs[i]->p_filesz,
596 segs[i]->p_memsz - segs[i]->p_filesz);
598 #ifdef SPARSE_MAPPING
600 * Wire down the pages
602 vm_map_wire(kernel_map,
603 (vm_offset_t) segbase,
604 (vm_offset_t) segbase + segs[i]->p_memsz,
609 ef->dynamic = (const Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
611 lf = linker_make_file(filename, ef, &link_elf_file_ops);
613 #ifdef SPARSE_MAPPING
614 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
615 (vm_offset_t) ef->address
616 + (ef->object->size << PAGE_SHIFT));
617 vm_object_deallocate(ef->object);
619 free(ef->address, M_LINKER);
625 lf->address = ef->address;
628 error = parse_dynamic(lf);
631 error = load_dependancies(lf);
634 error = relocate_file(lf);
638 /* Try and load the symbol table if it's present. (you can strip it!) */
639 nbytes = hdr->e_shnum * hdr->e_shentsize;
640 if (nbytes == 0 || hdr->e_shoff == 0)
642 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
647 error = vn_rdwr(UIO_READ, vp,
648 (caddr_t)shdr, nbytes, hdr->e_shoff,
649 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
654 for (i = 0; i < hdr->e_shnum; i++) {
655 if (shdr[i].sh_type == SHT_SYMTAB) {
657 symstrindex = shdr[i].sh_link;
660 if (symtabindex < 0 || symstrindex < 0)
663 symcnt = shdr[symtabindex].sh_size;
664 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK);
665 strcnt = shdr[symstrindex].sh_size;
666 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK);
668 if (ef->symbase == NULL || ef->strbase == NULL) {
672 error = vn_rdwr(UIO_READ, vp,
673 ef->symbase, symcnt, shdr[symtabindex].sh_offset,
674 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
677 error = vn_rdwr(UIO_READ, vp,
678 ef->strbase, strcnt, shdr[symstrindex].sh_offset,
679 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid, td);
683 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
684 ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
685 ef->ddbstrcnt = strcnt;
686 ef->ddbstrtab = ef->strbase;
688 lf->flags |= LINKER_FILE_LINKED;
696 linker_file_unload(lf);
698 free(shdr, M_LINKER);
700 free(firstpage, M_LINKER);
701 VOP_UNLOCK(vp, 0, td);
702 vn_close(vp, FREAD, td);
708 link_elf_unload_file(linker_file_t file)
710 elf_file_t ef = file->priv;
713 #ifdef SPARSE_MAPPING
715 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
716 (vm_offset_t) ef->address
717 + (ef->object->size << PAGE_SHIFT));
718 vm_object_deallocate(ef->object);
722 free(ef->address, M_LINKER);
725 free(ef->symbase, M_LINKER);
727 free(ef->strbase, M_LINKER);
733 link_elf_unload_module(linker_file_t file)
735 elf_file_t ef = file->priv;
740 preload_delete_name(file->filename);
744 load_dependancies(linker_file_t lf)
746 elf_file_t ef = lf->priv;
753 * All files are dependant on /kernel.
755 if (linker_kernel_file) {
756 linker_kernel_file->refs++;
757 linker_file_add_dependancy(lf, linker_kernel_file);
760 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
761 if (dp->d_tag == DT_NEEDED) {
762 name = ef->strtab + dp->d_un.d_val;
764 error = linker_load_file(name, &lfdep);
767 error = linker_file_add_dependancy(lf, lfdep);
778 symbol_name(elf_file_t ef, Elf_Word r_info)
782 if (ELF_R_SYM(r_info)) {
783 ref = ef->symtab + ELF_R_SYM(r_info);
784 return ef->strtab + ref->st_name;
790 relocate_file(linker_file_t lf)
792 elf_file_t ef = lf->priv;
793 const Elf_Rel *rellim;
795 const Elf_Rela *relalim;
796 const Elf_Rela *rela;
799 /* Perform relocations without addend if there are any: */
802 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
803 while (rel < rellim) {
804 symname = symbol_name(ef, rel->r_info);
805 if (elf_reloc(lf, rel, ELF_RELOC_REL, symname)) {
806 printf("link_elf: symbol %s undefined\n", symname);
813 /* Perform relocations with addend if there are any: */
816 relalim = (const Elf_Rela *)((const char *)ef->rela + ef->relasize);
817 while (rela < relalim) {
818 symname = symbol_name(ef, rela->r_info);
819 if (elf_reloc(lf, rela, ELF_RELOC_RELA, symname)) {
820 printf("link_elf: symbol %s undefined\n", symname);
827 /* Perform PLT relocations without addend if there are any: */
830 rellim = (const Elf_Rel *)((const char *)ef->pltrel + ef->pltrelsize);
831 while (rel < rellim) {
832 symname = symbol_name(ef, rel->r_info);
833 if (elf_reloc(lf, rel, ELF_RELOC_REL, symname)) {
834 printf("link_elf: symbol %s undefined\n", symname);
841 /* Perform relocations with addend if there are any: */
844 relalim = (const Elf_Rela *)((const char *)ef->pltrela + ef->pltrelasize);
845 while (rela < relalim) {
846 symname = symbol_name(ef, rela->r_info);
847 if (elf_reloc(lf, rela, ELF_RELOC_RELA, symname)) {
848 printf("link_elf: symbol %s undefined\n", symname);
859 * Hash function for symbol table lookup. Don't even think about changing
860 * this. It is specified by the System V ABI.
863 elf_hash(const char *name)
865 const unsigned char *p = (const unsigned char *) name;
871 if ((g = h & 0xf0000000) != 0)
879 link_elf_lookup_symbol(linker_file_t lf, const char* name, c_linker_sym_t* sym)
881 elf_file_t ef = lf->priv;
882 unsigned long symnum;
888 /* First, search hashed global symbols */
889 hash = elf_hash(name);
890 symnum = ef->buckets[hash % ef->nbuckets];
892 while (symnum != STN_UNDEF) {
893 if (symnum >= ef->nchains) {
894 printf("link_elf_lookup_symbol: corrupt symbol table\n");
898 symp = ef->symtab + symnum;
899 if (symp->st_name == 0) {
900 printf("link_elf_lookup_symbol: corrupt symbol table\n");
904 strp = ef->strtab + symp->st_name;
906 if (strcmp(name, strp) == 0) {
907 if (symp->st_shndx != SHN_UNDEF ||
908 (symp->st_value != 0 &&
909 ELF_ST_TYPE(symp->st_info) == STT_FUNC)
911 *sym = (c_linker_sym_t) symp;
918 symnum = ef->chains[symnum];
921 /* If we have not found it, look at the full table (if loaded) */
922 if (ef->symtab == ef->ddbsymtab)
925 /* Exhaustive search */
926 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
927 strp = ef->ddbstrtab + symp->st_name;
928 if (strcmp(name, strp) == 0) {
929 if (symp->st_shndx != SHN_UNDEF ||
930 (symp->st_value != 0 &&
931 ELF_ST_TYPE(symp->st_info) == STT_FUNC)) {
932 *sym = (c_linker_sym_t) symp;
943 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym, linker_symval_t* symval)
945 elf_file_t ef = lf->priv;
946 const Elf_Sym* es = (const Elf_Sym*) sym;
948 if (es >= ef->symtab && ((es - ef->symtab) < ef->nchains)) {
949 symval->name = ef->strtab + es->st_name;
950 symval->value = (caddr_t) ef->address + es->st_value;
951 symval->size = es->st_size;
954 if (ef->symtab == ef->ddbsymtab)
956 if (es >= ef->ddbsymtab && ((es - ef->ddbsymtab) < ef->ddbsymcnt)) {
957 symval->name = ef->ddbstrtab + es->st_name;
958 symval->value = (caddr_t) ef->address + es->st_value;
959 symval->size = es->st_size;
966 link_elf_search_symbol(linker_file_t lf, caddr_t value,
967 c_linker_sym_t* sym, long* diffp)
969 elf_file_t ef = lf->priv;
970 u_long off = (uintptr_t) (void *) value;
974 const Elf_Sym* best = 0;
977 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
978 if (es->st_name == 0)
980 st_value = es->st_value + (uintptr_t) (void *) ef->address;
981 if (off >= st_value) {
982 if (off - st_value < diff) {
983 diff = off - st_value;
987 } else if (off - st_value == diff) {
996 *sym = (c_linker_sym_t) best;
1002 * Look up a linker set on an ELF system.
1005 link_elf_lookup_set(linker_file_t lf, const char *name,
1006 void ***startp, void ***stopp, int *countp)
1009 linker_symval_t symval;
1011 void **start, **stop;
1012 int len, error = 0, count;
1014 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
1015 setsym = malloc(len, M_LINKER, M_WAITOK);
1019 /* get address of first entry */
1020 snprintf(setsym, len, "%s%s", "__start_set_", name);
1021 error = link_elf_lookup_symbol(lf, setsym, &sym);
1024 link_elf_symbol_values(lf, sym, &symval);
1025 if (symval.value == 0) {
1029 start = (void **)symval.value;
1031 /* get address of last entry */
1032 snprintf(setsym, len, "%s%s", "__stop_set_", name);
1033 error = link_elf_lookup_symbol(lf, setsym, &sym);
1036 link_elf_symbol_values(lf, sym, &symval);
1037 if (symval.value == 0) {
1041 stop = (void **)symval.value;
1043 /* and the number of entries */
1044 count = stop - start;
1055 free(setsym, M_LINKER);