Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 1 | /* Generate ELF backend handle. |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 2 | Copyright (C) 2000-2014 Red Hat, Inc. |
| 3 | This file is part of elfutils. |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 4 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 5 | This file is free software; you can redistribute it and/or modify |
| 6 | it under the terms of either |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 7 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 8 | * the GNU Lesser General Public License as published by the Free |
| 9 | Software Foundation; either version 3 of the License, or (at |
| 10 | your option) any later version |
| 11 | |
| 12 | or |
| 13 | |
| 14 | * the GNU General Public License as published by the Free |
| 15 | Software Foundation; either version 2 of the License, or (at |
| 16 | your option) any later version |
| 17 | |
| 18 | or both in parallel, as here. |
| 19 | |
| 20 | elfutils is distributed in the hope that it will be useful, but |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 21 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 22 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 23 | General Public License for more details. |
| 24 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 25 | You should have received copies of the GNU General Public License and |
| 26 | the GNU Lesser General Public License along with this program. If |
| 27 | not, see <http://www.gnu.org/licenses/>. */ |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 28 | |
| 29 | #ifdef HAVE_CONFIG_H |
| 30 | # include <config.h> |
| 31 | #endif |
| 32 | |
| 33 | #include <assert.h> |
| 34 | #include <dlfcn.h> |
| 35 | #include <error.h> |
| 36 | #include <libelfP.h> |
| 37 | #include <dwarf.h> |
| 38 | #include <stdlib.h> |
| 39 | #include <string.h> |
| 40 | #include <stdio.h> |
| 41 | |
| 42 | #include <libeblP.h> |
| 43 | |
| 44 | |
| 45 | /* This table should contain the complete list of architectures as far |
| 46 | as the ELF specification is concerned. */ |
| 47 | /* XXX When things are stable replace the string pointers with char |
| 48 | arrays to avoid relocations. */ |
| 49 | static const struct |
| 50 | { |
| 51 | const char *dsoname; |
| 52 | const char *emulation; |
| 53 | const char *prefix; |
| 54 | int prefix_len; |
| 55 | int em; |
| 56 | int class; |
| 57 | int data; |
| 58 | } machines[] = |
| 59 | { |
| 60 | { "i386", "elf_i386", "i386", 4, EM_386, ELFCLASS32, ELFDATA2LSB }, |
| 61 | { "ia64", "elf_ia64", "ia64", 4, EM_IA_64, ELFCLASS64, ELFDATA2LSB }, |
| 62 | { "alpha", "elf_alpha", "alpha", 5, EM_ALPHA, ELFCLASS64, ELFDATA2LSB }, |
| 63 | { "x86_64", "elf_x86_64", "x86_64", 6, EM_X86_64, ELFCLASS64, ELFDATA2LSB }, |
| 64 | { "ppc", "elf_ppc", "ppc", 3, EM_PPC, ELFCLASS32, ELFDATA2MSB }, |
| 65 | { "ppc64", "elf_ppc64", "ppc64", 5, EM_PPC64, ELFCLASS64, ELFDATA2MSB }, |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 66 | { "tilegx", "elf_tilegx", "tilegx", 6, EM_TILEGX, ELFCLASS64, ELFDATA2LSB }, |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 67 | // XXX class and machine fields need to be filled in for all archs. |
| 68 | { "sh", "elf_sh", "sh", 2, EM_SH, 0, 0 }, |
| 69 | { "arm", "ebl_arm", "arm", 3, EM_ARM, 0, 0 }, |
| 70 | { "sparc", "elf_sparcv9", "sparc", 5, EM_SPARCV9, 0, 0 }, |
| 71 | { "sparc", "elf_sparc", "sparc", 5, EM_SPARC, 0, 0 }, |
| 72 | { "sparc", "elf_sparcv8plus", "sparc", 5, EM_SPARC32PLUS, 0, 0 }, |
| 73 | { "s390", "ebl_s390", "s390", 4, EM_S390, 0, 0 }, |
| 74 | |
| 75 | { "m32", "elf_m32", "m32", 3, EM_M32, 0, 0 }, |
| 76 | { "m68k", "elf_m68k", "m68k", 4, EM_68K, 0, 0 }, |
| 77 | { "m88k", "elf_m88k", "m88k", 4, EM_88K, 0, 0 }, |
| 78 | { "i860", "elf_i860", "i860", 4, EM_860, 0, 0 }, |
| 79 | { "s370", "ebl_s370", "s370", 4, EM_S370, 0, 0 }, |
| 80 | { "parisc", "elf_parisc", "parisc", 6, EM_PARISC, 0, 0 }, |
| 81 | { "vpp500", "elf_vpp500", "vpp500", 5, EM_VPP500, 0, 0 }, |
| 82 | { "sparc", "elf_v8plus", "v8plus", 6, EM_SPARC32PLUS, 0, 0 }, |
| 83 | { "i960", "elf_i960", "i960", 4, EM_960, 0, 0 }, |
| 84 | { "v800", "ebl_v800", "v800", 4, EM_V800, 0, 0 }, |
| 85 | { "fr20", "ebl_fr20", "fr20", 4, EM_FR20, 0, 0 }, |
| 86 | { "rh32", "ebl_rh32", "rh32", 4, EM_RH32, 0, 0 }, |
| 87 | { "rce", "ebl_rce", "rce", 3, EM_RCE, 0, 0 }, |
| 88 | { "tricore", "elf_tricore", "tricore", 7, EM_TRICORE, 0, 0 }, |
| 89 | { "arc", "elf_arc", "arc", 3, EM_ARC, 0, 0 }, |
| 90 | { "h8", "elf_h8_300", "h8_300", 6, EM_H8_300, 0, 0 }, |
| 91 | { "h8", "elf_h8_300h", "h8_300h", 6, EM_H8_300H, 0, 0 }, |
| 92 | { "h8", "elf_h8s", "h8s", 6, EM_H8S, 0, 0 }, |
| 93 | { "h8", "elf_h8_500", "h8_500", 6, EM_H8_500, 0, 0 }, |
| 94 | { "coldfire", "elf_coldfire", "coldfire", 8, EM_COLDFIRE, 0, 0 }, |
| 95 | { "m68k", "elf_68hc12", "68hc12", 6, EM_68HC12, 0, 0 }, |
| 96 | { "mma", "elf_mma", "mma", 3, EM_MMA, 0, 0 }, |
| 97 | { "pcp", "elf_pcp", "pcp", 3, EM_PCP, 0, 0 }, |
| 98 | { "ncpu", "elf_ncpu", "ncpu", 4, EM_NCPU, 0, 0 }, |
| 99 | { "ndr1", "elf_ndr1", "ndr1", 4, EM_NDR1, 0, 0 }, |
| 100 | { "starcore", "elf_starcore", "starcore", 8, EM_STARCORE, 0, 0 }, |
| 101 | { "me16", "elf_me16", "em16", 4, EM_ME16, 0, 0 }, |
| 102 | { "st100", "elf_st100", "st100", 5, EM_ST100, 0, 0 }, |
| 103 | { "tinyj", "elf_tinyj", "tinyj", 5, EM_TINYJ, 0, 0 }, |
| 104 | { "pdsp", "elf_pdsp", "pdsp", 4, EM_PDSP, 0, 0 }, |
| 105 | { "fx66", "elf_fx66", "fx66", 4, EM_FX66, 0, 0 }, |
| 106 | { "st9plus", "elf_st9plus", "st9plus", 7, EM_ST9PLUS, 0, 0 }, |
| 107 | { "st7", "elf_st7", "st7", 3, EM_ST7, 0, 0 }, |
| 108 | { "m68k", "elf_68hc16", "68hc16", 6, EM_68HC16, 0, 0 }, |
| 109 | { "m68k", "elf_68hc11", "68hc11", 6, EM_68HC11, 0, 0 }, |
| 110 | { "m68k", "elf_68hc08", "68hc08", 6, EM_68HC08, 0, 0 }, |
| 111 | { "m68k", "elf_68hc05", "68hc05", 6, EM_68HC05, 0, 0 }, |
| 112 | { "svx", "elf_svx", "svx", 3, EM_SVX, 0, 0 }, |
| 113 | { "st19", "elf_st19", "st19", 4, EM_ST19, 0, 0 }, |
| 114 | { "vax", "elf_vax", "vax", 3, EM_VAX, 0, 0 }, |
| 115 | { "cris", "elf_cris", "cris", 4, EM_CRIS, 0, 0 }, |
| 116 | { "javelin", "elf_javelin", "javelin", 7, EM_JAVELIN, 0, 0 }, |
| 117 | { "firepath", "elf_firepath", "firepath", 8, EM_FIREPATH, 0, 0 }, |
| 118 | { "zsp", "elf_zsp", "zsp", 3, EM_ZSP, 0, 0 }, |
| 119 | { "mmix", "elf_mmix", "mmix", 4, EM_MMIX, 0, 0 }, |
| 120 | { "hunay", "elf_huany", "huany", 5, EM_HUANY, 0, 0 }, |
| 121 | { "prism", "elf_prism", "prism", 5, EM_PRISM, 0, 0 }, |
| 122 | { "avr", "elf_avr", "avr", 3, EM_AVR, 0, 0 }, |
| 123 | { "fr30", "elf_fr30", "fr30", 4, EM_FR30, 0, 0 }, |
| 124 | { "dv10", "elf_dv10", "dv10", 4, EM_D10V, 0, 0 }, |
| 125 | { "dv30", "elf_dv30", "dv30", 4, EM_D30V, 0, 0 }, |
| 126 | { "v850", "elf_v850", "v850", 4, EM_V850, 0, 0 }, |
| 127 | { "m32r", "elf_m32r", "m32r", 4, EM_M32R, 0, 0 }, |
| 128 | { "mn10300", "elf_mn10300", "mn10300", 7, EM_MN10300, 0, 0 }, |
| 129 | { "mn10200", "elf_mn10200", "mn10200", 7, EM_MN10200, 0, 0 }, |
| 130 | { "pj", "elf_pj", "pj", 2, EM_PJ, 0, 0 }, |
| 131 | { "openrisc", "elf_openrisc", "openrisc", 8, EM_OPENRISC, 0, 0 }, |
| 132 | { "arc", "elf_arc_a5", "arc_a5", 6, EM_ARC_A5, 0, 0 }, |
| 133 | { "xtensa", "elf_xtensa", "xtensa", 6, EM_XTENSA, 0, 0 }, |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 134 | { "aarch64", "elf_aarch64", "aarch64", 7, EM_AARCH64, ELFCLASS64, 0 }, |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 135 | }; |
| 136 | #define nmachines (sizeof (machines) / sizeof (machines[0])) |
| 137 | |
| 138 | |
| 139 | /* Default callbacks. Mostly they just return the error value. */ |
| 140 | static const char *default_object_type_name (int ignore, char *buf, |
| 141 | size_t len); |
| 142 | static const char *default_reloc_type_name (int ignore, char *buf, size_t len); |
| 143 | static bool default_reloc_type_check (int ignore); |
| 144 | static bool default_reloc_valid_use (Elf *elf, int ignore); |
| 145 | static Elf_Type default_reloc_simple_type (Ebl *ebl, int ignore); |
| 146 | static bool default_gotpc_reloc_check (Elf *elf, int ignore); |
| 147 | static const char *default_segment_type_name (int ignore, char *buf, |
| 148 | size_t len); |
| 149 | static const char *default_section_type_name (int ignore, char *buf, |
| 150 | size_t len); |
| 151 | static const char *default_section_name (int ignore, int ignore2, char *buf, |
| 152 | size_t len); |
| 153 | static const char *default_machine_flag_name (Elf64_Word *ignore); |
| 154 | static bool default_machine_flag_check (Elf64_Word flags); |
| 155 | static bool default_machine_section_flag_check (GElf_Xword flags); |
| 156 | static const char *default_symbol_type_name (int ignore, char *buf, |
| 157 | size_t len); |
| 158 | static const char *default_symbol_binding_name (int ignore, char *buf, |
| 159 | size_t len); |
| 160 | static const char *default_dynamic_tag_name (int64_t ignore, char *buf, |
| 161 | size_t len); |
| 162 | static bool default_dynamic_tag_check (int64_t ignore); |
| 163 | static GElf_Word default_sh_flags_combine (GElf_Word flags1, GElf_Word flags2); |
| 164 | static const char *default_osabi_name (int ignore, char *buf, size_t len); |
| 165 | static void default_destr (struct ebl *ignore); |
| 166 | static const char *default_core_note_type_name (uint32_t, char *buf, |
| 167 | size_t len); |
| 168 | static const char *default_object_note_type_name (const char *name, uint32_t, |
| 169 | char *buf, size_t len); |
| 170 | static int default_core_note (const GElf_Nhdr *nhdr, const char *name, |
| 171 | GElf_Word *regs_offset, size_t *nregloc, |
| 172 | const Ebl_Register_Location **reglocs, |
| 173 | size_t *nitems, const Ebl_Core_Item **); |
| 174 | static int default_auxv_info (GElf_Xword a_type, |
| 175 | const char **name, const char **format); |
| 176 | static bool default_object_note (const char *name, uint32_t type, |
| 177 | uint32_t descsz, const char *desc); |
| 178 | static bool default_debugscn_p (const char *name); |
| 179 | static bool default_copy_reloc_p (int reloc); |
| 180 | static bool default_none_reloc_p (int reloc); |
| 181 | static bool default_relative_reloc_p (int reloc); |
| 182 | static bool default_check_special_symbol (Elf *elf, GElf_Ehdr *ehdr, |
| 183 | const GElf_Sym *sym, |
| 184 | const char *name, |
| 185 | const GElf_Shdr *destshdr); |
| 186 | static bool default_check_st_other_bits (unsigned char st_other); |
| 187 | static bool default_check_special_section (Ebl *, int, |
| 188 | const GElf_Shdr *, const char *); |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 189 | static bool default_bss_plt_p (Elf *elf); |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 190 | static int default_return_value_location (Dwarf_Die *functypedie, |
| 191 | const Dwarf_Op **locops); |
| 192 | static ssize_t default_register_info (Ebl *ebl, |
| 193 | int regno, char *name, size_t namelen, |
| 194 | const char **prefix, |
| 195 | const char **setname, |
| 196 | int *bits, int *type); |
| 197 | static int default_syscall_abi (Ebl *ebl, int *sp, int *pc, |
| 198 | int *callno, int args[6]); |
| 199 | static bool default_check_object_attribute (Ebl *ebl, const char *vendor, |
| 200 | int tag, uint64_t value, |
| 201 | const char **tag_name, |
| 202 | const char **value_name); |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 203 | static bool default_check_reloc_target_type (Ebl *ebl, Elf64_Word sh_type); |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 204 | static int default_abi_cfi (Ebl *ebl, Dwarf_CIE *abi_info); |
| 205 | |
| 206 | |
| 207 | static void |
| 208 | fill_defaults (Ebl *result) |
| 209 | { |
| 210 | result->object_type_name = default_object_type_name; |
| 211 | result->reloc_type_name = default_reloc_type_name; |
| 212 | result->reloc_type_check = default_reloc_type_check; |
| 213 | result->reloc_valid_use = default_reloc_valid_use; |
| 214 | result->reloc_simple_type = default_reloc_simple_type; |
| 215 | result->gotpc_reloc_check = default_gotpc_reloc_check; |
| 216 | result->segment_type_name = default_segment_type_name; |
| 217 | result->section_type_name = default_section_type_name; |
| 218 | result->section_name = default_section_name; |
| 219 | result->machine_flag_name = default_machine_flag_name; |
| 220 | result->machine_flag_check = default_machine_flag_check; |
| 221 | result->machine_section_flag_check = default_machine_section_flag_check; |
| 222 | result->check_special_section = default_check_special_section; |
| 223 | result->symbol_type_name = default_symbol_type_name; |
| 224 | result->symbol_binding_name = default_symbol_binding_name; |
| 225 | result->dynamic_tag_name = default_dynamic_tag_name; |
| 226 | result->dynamic_tag_check = default_dynamic_tag_check; |
| 227 | result->sh_flags_combine = default_sh_flags_combine; |
| 228 | result->osabi_name = default_osabi_name; |
| 229 | result->core_note_type_name = default_core_note_type_name; |
| 230 | result->object_note_type_name = default_object_note_type_name; |
| 231 | result->core_note = default_core_note; |
| 232 | result->auxv_info = default_auxv_info; |
| 233 | result->object_note = default_object_note; |
| 234 | result->debugscn_p = default_debugscn_p; |
| 235 | result->copy_reloc_p = default_copy_reloc_p; |
| 236 | result->none_reloc_p = default_none_reloc_p; |
| 237 | result->relative_reloc_p = default_relative_reloc_p; |
| 238 | result->check_special_symbol = default_check_special_symbol; |
| 239 | result->check_st_other_bits = default_check_st_other_bits; |
| 240 | result->bss_plt_p = default_bss_plt_p; |
| 241 | result->return_value_location = default_return_value_location; |
| 242 | result->register_info = default_register_info; |
| 243 | result->syscall_abi = default_syscall_abi; |
| 244 | result->check_object_attribute = default_check_object_attribute; |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 245 | result->check_reloc_target_type = default_check_reloc_target_type; |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 246 | result->disasm = NULL; |
| 247 | result->abi_cfi = default_abi_cfi; |
| 248 | result->destr = default_destr; |
| 249 | result->sysvhash_entrysize = sizeof (Elf32_Word); |
| 250 | } |
| 251 | |
| 252 | |
| 253 | /* Find an appropriate backend for the file associated with ELF. */ |
| 254 | static Ebl * |
| 255 | openbackend (elf, emulation, machine) |
| 256 | Elf *elf; |
| 257 | const char *emulation; |
| 258 | GElf_Half machine; |
| 259 | { |
| 260 | Ebl *result; |
| 261 | size_t cnt; |
| 262 | |
| 263 | /* First allocate the data structure for the result. We do this |
| 264 | here since this assures that the structure is always large |
| 265 | enough. */ |
| 266 | result = (Ebl *) calloc (1, sizeof (Ebl)); |
| 267 | if (result == NULL) |
| 268 | { |
| 269 | // XXX uncomment |
| 270 | // __libebl_seterror (ELF_E_NOMEM); |
| 271 | return NULL; |
| 272 | } |
| 273 | |
| 274 | /* Fill in the default callbacks. The initializer for the machine |
| 275 | specific module can overwrite the values. */ |
| 276 | fill_defaults (result); |
| 277 | |
| 278 | /* XXX Currently all we do is to look at 'e_machine' value in the |
| 279 | ELF header. With an internal mapping table from EM_* value to |
| 280 | DSO name we try to load the appropriate module to handle this |
| 281 | binary type. |
| 282 | |
| 283 | Multiple modules for the same machine type are possible and they |
| 284 | will be tried in sequence. The lookup process will only stop |
| 285 | when a module which can handle the machine type is found or all |
| 286 | available matching modules are tried. */ |
| 287 | for (cnt = 0; cnt < nmachines; ++cnt) |
| 288 | if ((emulation != NULL && strcmp (emulation, machines[cnt].emulation) == 0) |
| 289 | || (emulation == NULL && machines[cnt].em == machine)) |
| 290 | { |
| 291 | /* Well, we know the emulation name now. */ |
| 292 | result->emulation = machines[cnt].emulation; |
| 293 | |
| 294 | /* We access some data structures directly. Make sure the 32 and |
| 295 | 64 bit variants are laid out the same. */ |
| 296 | assert (offsetof (Elf32_Ehdr, e_machine) |
| 297 | == offsetof (Elf64_Ehdr, e_machine)); |
| 298 | assert (sizeof (((Elf32_Ehdr *) 0)->e_machine) |
| 299 | == sizeof (((Elf64_Ehdr *) 0)->e_machine)); |
| 300 | assert (offsetof (Elf, state.elf32.ehdr) |
| 301 | == offsetof (Elf, state.elf64.ehdr)); |
| 302 | |
| 303 | /* Prefer taking the information from the ELF file. */ |
| 304 | if (elf == NULL) |
| 305 | { |
| 306 | result->machine = machines[cnt].em; |
| 307 | result->class = machines[cnt].class; |
| 308 | result->data = machines[cnt].data; |
| 309 | } |
| 310 | else |
| 311 | { |
| 312 | result->machine = elf->state.elf32.ehdr->e_machine; |
| 313 | result->class = elf->state.elf32.ehdr->e_ident[EI_CLASS]; |
| 314 | result->data = elf->state.elf32.ehdr->e_ident[EI_DATA]; |
| 315 | } |
| 316 | |
| 317 | #ifndef LIBEBL_SUBDIR |
| 318 | # define LIBEBL_SUBDIR PACKAGE |
| 319 | #endif |
| 320 | #define ORIGINDIR "$ORIGIN/../$LIB/" LIBEBL_SUBDIR "/" |
| 321 | |
| 322 | /* Give it a try. At least the machine type matches. First |
| 323 | try to load the module. */ |
| 324 | char dsoname[100]; |
| 325 | strcpy (stpcpy (stpcpy (dsoname, ORIGINDIR "libebl_"), |
| 326 | machines[cnt].dsoname), |
| 327 | ".so"); |
| 328 | |
| 329 | void *h = dlopen (dsoname, RTLD_LAZY); |
| 330 | if (h == NULL) |
| 331 | { |
| 332 | strcpy (stpcpy (stpcpy (dsoname, "libebl_"), |
| 333 | machines[cnt].dsoname), |
| 334 | ".so"); |
| 335 | h = dlopen (dsoname, RTLD_LAZY); |
| 336 | } |
| 337 | |
| 338 | /* Try without an explicit path. */ |
| 339 | if (h != NULL) |
| 340 | { |
| 341 | /* We managed to load the object. Now see whether the |
| 342 | initialization function likes our file. */ |
| 343 | static const char version[] = MODVERSION; |
| 344 | const char *modversion; |
| 345 | ebl_bhinit_t initp; |
| 346 | char symname[machines[cnt].prefix_len + sizeof "_init"]; |
| 347 | |
| 348 | strcpy (mempcpy (symname, machines[cnt].prefix, |
| 349 | machines[cnt].prefix_len), "_init"); |
| 350 | |
| 351 | initp = (ebl_bhinit_t) dlsym (h, symname); |
| 352 | if (initp != NULL |
| 353 | && (modversion = initp (elf, machine, result, sizeof (Ebl))) |
| 354 | && strcmp (version, modversion) == 0) |
| 355 | { |
| 356 | /* We found a module to handle our file. */ |
| 357 | result->dlhandle = h; |
| 358 | result->elf = elf; |
| 359 | |
| 360 | /* A few entries are mandatory. */ |
| 361 | assert (result->name != NULL); |
| 362 | assert (result->destr != NULL); |
| 363 | |
| 364 | return result; |
| 365 | } |
| 366 | |
| 367 | /* Not the module we need. */ |
| 368 | (void) dlclose (h); |
| 369 | } |
| 370 | |
| 371 | /* We cannot find a DSO but the emulation/machine ID matches. |
| 372 | Return that information. */ |
| 373 | result->dlhandle = NULL; |
| 374 | result->elf = elf; |
| 375 | result->name = machines[cnt].prefix; |
| 376 | fill_defaults (result); |
| 377 | |
| 378 | return result; |
| 379 | } |
| 380 | |
| 381 | /* Nothing matched. We use only the default callbacks. */ |
| 382 | result->dlhandle = NULL; |
| 383 | result->elf = elf; |
| 384 | result->emulation = "<unknown>"; |
| 385 | result->name = "<unknown>"; |
| 386 | fill_defaults (result); |
| 387 | |
| 388 | return result; |
| 389 | } |
| 390 | |
| 391 | |
| 392 | /* Find an appropriate backend for the file associated with ELF. */ |
| 393 | Ebl * |
| 394 | ebl_openbackend (elf) |
| 395 | Elf *elf; |
| 396 | { |
| 397 | GElf_Ehdr ehdr_mem; |
| 398 | GElf_Ehdr *ehdr; |
| 399 | |
| 400 | /* Get the ELF header of the object. */ |
| 401 | ehdr = gelf_getehdr (elf, &ehdr_mem); |
| 402 | if (ehdr == NULL) |
| 403 | { |
| 404 | // XXX uncomment |
| 405 | // __libebl_seterror (elf_errno ()); |
| 406 | return NULL; |
| 407 | } |
| 408 | |
| 409 | return openbackend (elf, NULL, ehdr->e_machine); |
| 410 | } |
| 411 | |
| 412 | |
| 413 | /* Find backend without underlying ELF file. */ |
| 414 | Ebl * |
| 415 | ebl_openbackend_machine (machine) |
| 416 | GElf_Half machine; |
| 417 | { |
| 418 | return openbackend (NULL, NULL, machine); |
| 419 | } |
| 420 | |
| 421 | |
| 422 | /* Find backend with given emulation name. */ |
| 423 | Ebl * |
| 424 | ebl_openbackend_emulation (const char *emulation) |
| 425 | { |
| 426 | return openbackend (NULL, emulation, EM_NONE); |
| 427 | } |
| 428 | |
| 429 | |
| 430 | /* Default callbacks. Mostly they just return the error value. */ |
| 431 | static const char * |
| 432 | default_object_type_name (int ignore __attribute__ ((unused)), |
| 433 | char *buf __attribute__ ((unused)), |
| 434 | size_t len __attribute__ ((unused))) |
| 435 | { |
| 436 | return NULL; |
| 437 | } |
| 438 | |
| 439 | static const char * |
| 440 | default_reloc_type_name (int ignore __attribute__ ((unused)), |
| 441 | char *buf __attribute__ ((unused)), |
| 442 | size_t len __attribute__ ((unused))) |
| 443 | { |
| 444 | return NULL; |
| 445 | } |
| 446 | |
| 447 | static bool |
| 448 | default_reloc_type_check (int ignore __attribute__ ((unused))) |
| 449 | { |
| 450 | return false; |
| 451 | } |
| 452 | |
| 453 | static bool |
| 454 | default_reloc_valid_use (Elf *elf __attribute__ ((unused)), |
| 455 | int ignore __attribute__ ((unused))) |
| 456 | { |
| 457 | return false; |
| 458 | } |
| 459 | |
| 460 | static Elf_Type |
| 461 | default_reloc_simple_type (Ebl *eh __attribute__ ((unused)), |
| 462 | int ignore __attribute__ ((unused))) |
| 463 | { |
| 464 | return ELF_T_NUM; |
| 465 | } |
| 466 | |
| 467 | static bool |
| 468 | default_gotpc_reloc_check (Elf *elf __attribute__ ((unused)), |
| 469 | int ignore __attribute__ ((unused))) |
| 470 | { |
| 471 | return false; |
| 472 | } |
| 473 | |
| 474 | static const char * |
| 475 | default_segment_type_name (int ignore __attribute__ ((unused)), |
| 476 | char *buf __attribute__ ((unused)), |
| 477 | size_t len __attribute__ ((unused))) |
| 478 | { |
| 479 | return NULL; |
| 480 | } |
| 481 | |
| 482 | static const char * |
| 483 | default_section_type_name (int ignore __attribute__ ((unused)), |
| 484 | char *buf __attribute__ ((unused)), |
| 485 | size_t len __attribute__ ((unused))) |
| 486 | { |
| 487 | return NULL; |
| 488 | } |
| 489 | |
| 490 | static const char * |
| 491 | default_section_name (int ignore __attribute__ ((unused)), |
| 492 | int ignore2 __attribute__ ((unused)), |
| 493 | char *buf __attribute__ ((unused)), |
| 494 | size_t len __attribute__ ((unused))) |
| 495 | { |
| 496 | return NULL; |
| 497 | } |
| 498 | |
| 499 | static const char * |
| 500 | default_machine_flag_name (Elf64_Word *ignore __attribute__ ((unused))) |
| 501 | { |
| 502 | return NULL; |
| 503 | } |
| 504 | |
| 505 | static bool |
| 506 | default_machine_flag_check (Elf64_Word flags __attribute__ ((unused))) |
| 507 | { |
| 508 | return flags == 0; |
| 509 | } |
| 510 | |
| 511 | static bool |
| 512 | default_machine_section_flag_check (GElf_Xword flags) |
| 513 | { |
| 514 | return flags == 0; |
| 515 | } |
| 516 | |
| 517 | static bool |
| 518 | default_check_special_section (Ebl *ebl __attribute__ ((unused)), |
| 519 | int ndx __attribute__ ((unused)), |
| 520 | const GElf_Shdr *shdr __attribute__ ((unused)), |
| 521 | const char *sname __attribute__ ((unused))) |
| 522 | { |
| 523 | return false; |
| 524 | } |
| 525 | |
| 526 | static const char * |
| 527 | default_symbol_type_name (int ignore __attribute__ ((unused)), |
| 528 | char *buf __attribute__ ((unused)), |
| 529 | size_t len __attribute__ ((unused))) |
| 530 | { |
| 531 | return NULL; |
| 532 | } |
| 533 | |
| 534 | static const char * |
| 535 | default_symbol_binding_name (int ignore __attribute__ ((unused)), |
| 536 | char *buf __attribute__ ((unused)), |
| 537 | size_t len __attribute__ ((unused))) |
| 538 | { |
| 539 | return NULL; |
| 540 | } |
| 541 | |
| 542 | static const char * |
| 543 | default_dynamic_tag_name (int64_t ignore __attribute__ ((unused)), |
| 544 | char *buf __attribute__ ((unused)), |
| 545 | size_t len __attribute__ ((unused))) |
| 546 | { |
| 547 | return NULL; |
| 548 | } |
| 549 | |
| 550 | static bool |
| 551 | default_dynamic_tag_check (int64_t ignore __attribute__ ((unused))) |
| 552 | { |
| 553 | return false; |
| 554 | } |
| 555 | |
| 556 | static GElf_Word |
| 557 | default_sh_flags_combine (GElf_Word flags1, GElf_Word flags2) |
| 558 | { |
| 559 | return SH_FLAGS_COMBINE (flags1, flags2); |
| 560 | } |
| 561 | |
| 562 | static void |
| 563 | default_destr (struct ebl *ignore __attribute__ ((unused))) |
| 564 | { |
| 565 | } |
| 566 | |
| 567 | static const char * |
| 568 | default_osabi_name (int ignore __attribute__ ((unused)), |
| 569 | char *buf __attribute__ ((unused)), |
| 570 | size_t len __attribute__ ((unused))) |
| 571 | { |
| 572 | return NULL; |
| 573 | } |
| 574 | |
| 575 | static const char * |
| 576 | default_core_note_type_name (uint32_t ignore __attribute__ ((unused)), |
| 577 | char *buf __attribute__ ((unused)), |
| 578 | size_t len __attribute__ ((unused))) |
| 579 | { |
| 580 | return NULL; |
| 581 | } |
| 582 | |
| 583 | static int |
| 584 | default_auxv_info (GElf_Xword a_type __attribute__ ((unused)), |
| 585 | const char **name __attribute__ ((unused)), |
| 586 | const char **format __attribute__ ((unused))) |
| 587 | { |
| 588 | return 0; |
| 589 | } |
| 590 | |
| 591 | static int |
| 592 | default_core_note (const GElf_Nhdr *nhdr __attribute__ ((unused)), |
| 593 | const char *name __attribute__ ((unused)), |
| 594 | GElf_Word *ro __attribute__ ((unused)), |
| 595 | size_t *nregloc __attribute__ ((unused)), |
| 596 | const Ebl_Register_Location **reglocs |
| 597 | __attribute__ ((unused)), |
| 598 | size_t *nitems __attribute__ ((unused)), |
| 599 | const Ebl_Core_Item **items __attribute__ ((unused))) |
| 600 | { |
| 601 | return 0; |
| 602 | } |
| 603 | |
| 604 | static const char * |
| 605 | default_object_note_type_name (const char *name __attribute__ ((unused)), |
| 606 | uint32_t ignore __attribute__ ((unused)), |
| 607 | char *buf __attribute__ ((unused)), |
| 608 | size_t len __attribute__ ((unused))) |
| 609 | { |
| 610 | return NULL; |
| 611 | } |
| 612 | |
| 613 | static bool |
| 614 | default_object_note (const char *name __attribute__ ((unused)), |
| 615 | uint32_t type __attribute__ ((unused)), |
| 616 | uint32_t descsz __attribute__ ((unused)), |
| 617 | const char *desc __attribute__ ((unused))) |
| 618 | { |
| 619 | return NULL; |
| 620 | } |
| 621 | |
| 622 | static bool |
| 623 | default_debugscn_p (const char *name) |
| 624 | { |
| 625 | /* We know by default only about the DWARF debug sections which have |
| 626 | fixed names. */ |
| 627 | static const char *dwarf_scn_names[] = |
| 628 | { |
| 629 | /* DWARF 1 */ |
| 630 | ".debug", |
| 631 | ".line", |
| 632 | /* GNU DWARF 1 extensions */ |
| 633 | ".debug_srcinfo", |
| 634 | ".debug_sfnames", |
| 635 | /* DWARF 1.1 and DWARF 2 */ |
| 636 | ".debug_aranges", |
| 637 | ".debug_pubnames", |
| 638 | /* DWARF 2 */ |
| 639 | ".debug_info", |
| 640 | ".debug_abbrev", |
| 641 | ".debug_line", |
| 642 | ".debug_frame", |
| 643 | ".debug_str", |
| 644 | ".debug_loc", |
| 645 | ".debug_macinfo", |
| 646 | /* DWARF 3 */ |
| 647 | ".debug_ranges", |
| 648 | ".debug_pubtypes", |
| 649 | /* DWARF 4 */ |
| 650 | ".debug_types", |
| 651 | /* GDB DWARF 4 extension */ |
| 652 | ".gdb_index", |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 653 | /* GNU/DWARF 5 extension/proposal */ |
| 654 | ".debug_macro", |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 655 | /* SGI/MIPS DWARF 2 extensions */ |
| 656 | ".debug_weaknames", |
| 657 | ".debug_funcnames", |
| 658 | ".debug_typenames", |
| 659 | ".debug_varnames" |
| 660 | }; |
| 661 | const size_t ndwarf_scn_names = (sizeof (dwarf_scn_names) |
| 662 | / sizeof (dwarf_scn_names[0])); |
| 663 | for (size_t cnt = 0; cnt < ndwarf_scn_names; ++cnt) |
| 664 | if (strcmp (name, dwarf_scn_names[cnt]) == 0) |
| 665 | return true; |
| 666 | |
| 667 | return false; |
| 668 | } |
| 669 | |
| 670 | static bool |
| 671 | default_copy_reloc_p (int reloc __attribute__ ((unused))) |
| 672 | { |
| 673 | return false; |
| 674 | } |
| 675 | strong_alias (default_copy_reloc_p, default_none_reloc_p) |
| 676 | strong_alias (default_copy_reloc_p, default_relative_reloc_p) |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 677 | |
| 678 | static bool |
| 679 | default_check_special_symbol (Elf *elf __attribute__ ((unused)), |
| 680 | GElf_Ehdr *ehdr __attribute__ ((unused)), |
| 681 | const GElf_Sym *sym __attribute__ ((unused)), |
| 682 | const char *name __attribute__ ((unused)), |
| 683 | const GElf_Shdr *destshdr __attribute__ ((unused))) |
| 684 | { |
| 685 | return false; |
| 686 | } |
| 687 | |
| 688 | static bool |
| 689 | default_check_st_other_bits (unsigned char st_other __attribute__ ((unused))) |
| 690 | { |
| 691 | return false; |
| 692 | } |
| 693 | |
| 694 | |
| 695 | static bool |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 696 | default_bss_plt_p (Elf *elf __attribute__ ((unused))) |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 697 | { |
| 698 | return false; |
| 699 | } |
| 700 | |
| 701 | static int |
| 702 | default_return_value_location (Dwarf_Die *functypedie __attribute__ ((unused)), |
| 703 | const Dwarf_Op **locops __attribute__ ((unused))) |
| 704 | { |
| 705 | return -2; |
| 706 | } |
| 707 | |
| 708 | static ssize_t |
| 709 | default_register_info (Ebl *ebl __attribute__ ((unused)), |
| 710 | int regno, char *name, size_t namelen, |
| 711 | const char **prefix, |
| 712 | const char **setname, |
| 713 | int *bits, int *type) |
| 714 | { |
| 715 | if (name == NULL) |
| 716 | return 0; |
| 717 | |
| 718 | *setname = "???"; |
| 719 | *prefix = ""; |
| 720 | *bits = -1; |
| 721 | *type = DW_ATE_void; |
| 722 | return snprintf (name, namelen, "reg%d", regno); |
| 723 | } |
| 724 | |
| 725 | static int |
| 726 | default_syscall_abi (Ebl *ebl __attribute__ ((unused)), |
| 727 | int *sp, int *pc, int *callno, int args[6]) |
| 728 | { |
| 729 | *sp = *pc = *callno = -1; |
| 730 | args[0] = -1; |
| 731 | args[1] = -1; |
| 732 | args[2] = -1; |
| 733 | args[3] = -1; |
| 734 | args[4] = -1; |
| 735 | args[5] = -1; |
| 736 | return -1; |
| 737 | } |
| 738 | |
| 739 | static bool |
| 740 | default_check_object_attribute (Ebl *ebl __attribute__ ((unused)), |
| 741 | const char *vendor __attribute__ ((unused)), |
| 742 | int tag __attribute__ ((unused)), |
| 743 | uint64_t value __attribute__ ((unused)), |
| 744 | const char **tag_name, const char **value_name) |
| 745 | { |
| 746 | *tag_name = NULL; |
| 747 | *value_name = NULL; |
| 748 | return false; |
| 749 | } |
| 750 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 751 | static bool |
| 752 | default_check_reloc_target_type (Ebl *ebl __attribute__ ((unused)), |
| 753 | Elf64_Word sh_type __attribute__ ((unused))) |
| 754 | { |
| 755 | return false; |
| 756 | } |
| 757 | |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 758 | static int |
| 759 | default_abi_cfi (Ebl *ebl __attribute__ ((unused)), |
| 760 | Dwarf_CIE *abi_info __attribute__ ((unused))) |
| 761 | { |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame] | 762 | return -1; |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 763 | } |