2 * CRIS ELF shared library loader support.
4 * Program to load an elf binary on a linux system, and run it.
5 * References to symbols in sharable libraries can be resolved
6 * by either an ELF sharable library or a linux style of shared
9 * Copyright (C) 2002-2004, Axis Communications AB
12 * Author: Tobias Anderberg, <tobiasa@axis.com>
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * 2. The name of the above contributors may not be
20 * used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 /* Defined in resolve.S. */
39 extern int _dl_linux_resolve(void);
42 _dl_linux_resolver(struct elf_resolve *tpnt, int reloc_entry)
51 ELF_RELOC *this_reloc;
52 unsigned long instr_addr;
54 rel_addr = (char *)tpnt->dynamic_info[DT_JMPREL];
56 this_reloc = (ELF_RELOC *)(intptr_t)(rel_addr + reloc_entry);
57 symtab_index = ELF32_R_SYM(this_reloc->r_info);
59 symtab = (Elf32_Sym *)(intptr_t)tpnt->dynamic_info[DT_SYMTAB];
60 strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
61 symname = strtab + symtab[symtab_index].st_name;
63 /* Address of the jump instruction to fix up. */
64 instr_addr = ((unsigned long)this_reloc->r_offset +
65 (unsigned long)tpnt->loadaddr);
66 got_addr = (char **)instr_addr;
68 /* Get the address of the GOT entry. */
69 new_addr = _dl_find_hash(symname, tpnt->symbol_scope, tpnt, ELF_RTYPE_CLASS_PLT, NULL);
70 if (unlikely(!new_addr)) {
71 _dl_dprintf(2, "%s: Can't resolve symbol '%s'\n", _dl_progname, symname);
75 #if defined (__SUPPORT_LD_DEBUG__)
76 if (_dl_debug_bindings) {
77 _dl_dprintf(_dl_debug_file, "\nresolve function: %s", symname);
79 _dl_dprintf(_dl_debug_file,
80 "\n\tpatched: %x ==> %x @ %x\n",
81 *got_addr, new_addr, got_addr);
83 if (!_dl_debug_nofixups) {
90 return (unsigned long)new_addr;
94 _dl_parse(struct elf_resolve *tpnt, struct dyn_elf *scope,
95 unsigned long rel_addr, unsigned long rel_size,
96 int (*reloc_fnc)(struct elf_resolve *tpnt, struct dyn_elf *scope,
97 ELF_RELOC *rpnt, Elf32_Sym *symtab, char *strtab))
105 /* Parse the relocation information. */
106 rpnt = (ELF_RELOC *)(intptr_t)rel_addr;
107 rel_size /= sizeof(ELF_RELOC);
109 symtab = (Elf32_Sym *)(intptr_t)tpnt->dynamic_info[DT_SYMTAB];
110 strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
112 for (i = 0; i < rel_size; i++, rpnt++) {
115 symtab_index = ELF32_R_SYM(rpnt->r_info);
117 debug_sym(symtab, strtab, symtab_index);
118 debug_reloc(symtab, strtab, rpnt);
120 /* Pass over to actual relocation function. */
121 res = reloc_fnc(tpnt, scope, rpnt, symtab, strtab);
126 _dl_dprintf(2, "\n%s: ", _dl_progname);
129 _dl_dprintf(2, "symbol '%s': ",
130 strtab + symtab[symtab_index].st_name);
132 if (unlikely(res < 0)) {
133 int reloc_type = ELF32_R_TYPE(rpnt->r_info);
135 #if defined (__SUPPORT_LD_DEBUG__)
136 _dl_dprintf(2, "can't handle reloc type %s\n",
137 _dl_reltypes(reloc_type));
139 _dl_dprintf(2, "can't handle reloc type %x\n",
143 } else if (unlikely(res > 0)) {
144 _dl_dprintf(2, "can't resolve symbol\n");
153 _dl_do_reloc(struct elf_resolve *tpnt, struct dyn_elf *scope,
154 ELF_RELOC *rpnt, Elf32_Sym *symtab, char *strtab)
159 unsigned long *reloc_addr;
160 unsigned long symbol_addr;
161 #if defined (__SUPPORT_LD_DEBUG__)
162 unsigned long old_val;
164 struct symbol_ref sym_ref;
166 reloc_addr = (unsigned long *)(intptr_t)(tpnt->loadaddr + (unsigned long)rpnt->r_offset);
167 reloc_type = ELF32_R_TYPE(rpnt->r_info);
168 symtab_index = ELF32_R_SYM(rpnt->r_info);
170 sym_ref.sym = &symtab[symtab_index];
172 symname = strtab + symtab[symtab_index].st_name;
175 if (symtab[symtab_index].st_shndx != SHN_UNDEF &&
176 ELF32_ST_BIND(symtab[symtab_index].st_info) == STB_LOCAL) {
177 symbol_addr = (unsigned long)tpnt->loadaddr;
179 symbol_addr = (unsigned long)_dl_find_hash(symname, scope, tpnt,
180 elf_machine_type_class(reloc_type), &sym_ref);
183 if (unlikely(!symbol_addr && ELF32_ST_BIND(symtab[symtab_index].st_info) != STB_WEAK)) {
184 _dl_dprintf(2, "%s: can't resolve symbol '%s'\n", _dl_progname, symname);
188 symbol_addr += rpnt->r_addend;
191 #if defined (__SUPPORT_LD_DEBUG__)
192 old_val = *reloc_addr;
195 switch (reloc_type) {
198 case R_CRIS_GLOB_DAT:
199 case R_CRIS_JUMP_SLOT:
201 *reloc_addr = symbol_addr;
204 #if defined (__SUPPORT_LD_DEBUG__)
206 _dl_dprintf(_dl_debug_file,
207 "\n%s move %d bytes from %x to %x",
208 symname, symtab[symtab_index].st_size,
209 symbol_addr, reloc_addr);
212 _dl_memcpy((char *)reloc_addr,
214 symtab[symtab_index].st_size);
216 case R_CRIS_RELATIVE:
217 *reloc_addr = (unsigned long)tpnt->loadaddr + rpnt->r_addend;
220 return -1; /* Calls _dl_exit(1). */
223 #if defined (__SUPPORT_LD_DEBUG__)
224 if (_dl_debug_reloc && _dl_debug_detail)
225 _dl_dprintf(_dl_debug_file, "\n\tpatched: %x ==> %x @ %x\n",
226 old_val, *reloc_addr, reloc_addr);
233 _dl_do_lazy_reloc(struct elf_resolve *tpnt, struct dyn_elf *scope,
234 ELF_RELOC *rpnt, Elf32_Sym *symtab, char *strtab)
237 unsigned long *reloc_addr;
238 #if defined (__SUPPORT_LD_DEBUG__)
239 unsigned long old_val;
242 /* Don't care about these, just keep the compiler happy. */
247 reloc_addr = (unsigned long *)(intptr_t)(tpnt->loadaddr + (unsigned long)rpnt->r_offset);
248 reloc_type = ELF32_R_TYPE(rpnt->r_info);
250 #if defined (__SUPPORT_LD_DEBUG__)
251 old_val = *reloc_addr;
254 switch (reloc_type) {
257 case R_CRIS_JUMP_SLOT:
258 *reloc_addr += (unsigned long)tpnt->loadaddr;
261 return -1; /* Calls _dl_exit(1). */
264 #if defined (__SUPPORT_LD_DEBUG__)
265 if (_dl_debug_reloc && _dl_debug_detail)
266 _dl_dprintf(_dl_debug_file, "\n\tpatched: %x ==> %x @ %x\n",
267 old_val, *reloc_addr, reloc_addr);
273 /* External interface to the generic part of the dynamic linker. */
276 _dl_parse_lazy_relocation_information(struct dyn_elf *rpnt,
277 unsigned long rel_addr,
278 unsigned long rel_size)
280 (void)_dl_parse(rpnt->dyn, NULL, rel_addr, rel_size, _dl_do_lazy_reloc);
284 _dl_parse_relocation_information(struct dyn_elf *rpnt,
285 unsigned long rel_addr,
286 unsigned long rel_size)
288 return _dl_parse(rpnt->dyn, rpnt->dyn->symbol_scope, rel_addr, rel_size, _dl_do_reloc);