| /* Returns the file name and crc stored in the .gnu_debuglink if found. |
| Copyright (C) 2014 Red Hat, Inc. |
| This file is part of elfutils. |
| |
| This file is free software; you can redistribute it and/or modify |
| it under the terms of either |
| |
| * the GNU Lesser General Public License as published by the Free |
| Software Foundation; either version 3 of the License, or (at |
| your option) any later version |
| |
| or |
| |
| * the GNU General Public License as published by the Free |
| Software Foundation; either version 2 of the License, or (at |
| your option) any later version |
| |
| or both in parallel, as here. |
| |
| elfutils is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received copies of the GNU General Public License and |
| the GNU Lesser General Public License along with this program. If |
| not, see <http://www.gnu.org/licenses/>. */ |
| |
| #ifdef HAVE_CONFIG_H |
| # include <config.h> |
| #endif |
| |
| #include "libdwelfP.h" |
| |
| const char * |
| dwelf_elf_gnu_debuglink (Elf *elf, GElf_Word *crc) |
| { |
| size_t shstrndx; |
| if (elf_getshdrstrndx (elf, &shstrndx) < 0) |
| return NULL; |
| |
| Elf_Scn *scn = NULL; |
| while ((scn = elf_nextscn (elf, scn)) != NULL) |
| { |
| GElf_Shdr shdr_mem; |
| GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); |
| if (shdr == NULL) |
| return NULL; |
| |
| const char *name = elf_strptr (elf, shstrndx, shdr->sh_name); |
| if (name == NULL) |
| return NULL; |
| |
| if (!strcmp (name, ".gnu_debuglink")) |
| break; |
| } |
| |
| if (scn == NULL) |
| return NULL; |
| |
| /* Found the .gnu_debuglink section. Extract its contents. */ |
| Elf_Data *rawdata = elf_rawdata (scn, NULL); |
| if (rawdata == NULL) |
| return NULL; |
| |
| /* The CRC comes after the zero-terminated file name, |
| (aligned up to 4 bytes) at the end of the section data. */ |
| if (rawdata->d_size <= sizeof *crc |
| || memchr (rawdata->d_buf, '\0', rawdata->d_size - sizeof *crc) == NULL) |
| return NULL; |
| |
| Elf_Data crcdata = |
| { |
| .d_type = ELF_T_WORD, |
| .d_buf = crc, |
| .d_size = sizeof *crc, |
| .d_version = EV_CURRENT, |
| }; |
| Elf_Data conv = |
| { |
| .d_type = ELF_T_WORD, |
| .d_buf = rawdata->d_buf + rawdata->d_size - sizeof *crc, |
| .d_size = sizeof *crc, |
| .d_version = EV_CURRENT, |
| }; |
| |
| GElf_Ehdr ehdr_mem; |
| GElf_Ehdr *ehdr = gelf_getehdr (elf, &ehdr_mem); |
| if (ehdr == NULL) |
| return NULL; |
| |
| Elf_Data *d = gelf_xlatetom (elf, &crcdata, &conv, ehdr->e_ident[EI_DATA]); |
| if (d == NULL) |
| return NULL; |
| assert (d == &crcdata); |
| |
| return rawdata->d_buf; |
| } |
| INTDEF(dwelf_elf_gnu_debuglink) |