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Diffstat (limited to 'REORG.TODO/elf/readlib.c')
-rw-r--r-- | REORG.TODO/elf/readlib.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/REORG.TODO/elf/readlib.c b/REORG.TODO/elf/readlib.c new file mode 100644 index 0000000000..d278a189b2 --- /dev/null +++ b/REORG.TODO/elf/readlib.c @@ -0,0 +1,212 @@ +/* Copyright (C) 1999-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Andreas Jaeger <aj@suse.de>, 1999 and + Jakub Jelinek <jakub@redhat.com>, 1999. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published + by the Free Software Foundation; version 2 of the License, or + (at your option) any later version. + + This program 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 a copy of the GNU General Public License + along with this program; if not, see <http://www.gnu.org/licenses/>. */ + +/* The code in this file and in readelflib is a heavily simplified + version of the readelf program that's part of the current binutils + development version. Besides the simplification, it has also been + modified to read some other file formats. */ + +#include <a.out.h> +#include <elf.h> +#include <error.h> +#include <libintl.h> +#include <link.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> +#include <sys/mman.h> +#include <sys/param.h> +#include <sys/stat.h> +#include <gnu/lib-names.h> + +#include <ldconfig.h> + +#define Elf32_CLASS ELFCLASS32 +#define Elf64_CLASS ELFCLASS64 + +struct known_names +{ + const char *soname; + int flag; +}; + +static struct known_names interpreters[] = +{ + { "/lib/" LD_SO, FLAG_ELF_LIBC6 }, +#ifdef SYSDEP_KNOWN_INTERPRETER_NAMES + SYSDEP_KNOWN_INTERPRETER_NAMES +#endif +}; + +static struct known_names known_libs[] = +{ + { LIBC_SO, FLAG_ELF_LIBC6 }, + { LIBM_SO, FLAG_ELF_LIBC6 }, +#ifdef SYSDEP_KNOWN_LIBRARY_NAMES + SYSDEP_KNOWN_LIBRARY_NAMES +#endif +}; + + +/* Check if string corresponds to a GDB Python file. */ +static bool +is_gdb_python_file (const char *name) +{ + size_t len = strlen (name); + return len > 7 && strcmp (name + len - 7, "-gdb.py") == 0; +} + +/* Returns 0 if everything is ok, != 0 in case of error. */ +int +process_file (const char *real_file_name, const char *file_name, + const char *lib, int *flag, unsigned int *osversion, + char **soname, int is_link, struct stat64 *stat_buf) +{ + FILE *file; + struct stat64 statbuf; + void *file_contents; + int ret; + ElfW(Ehdr) *elf_header; + struct exec *aout_header; + + ret = 0; + *flag = FLAG_ANY; + *soname = NULL; + + file = fopen (real_file_name, "rb"); + if (file == NULL) + { + /* No error for stale symlink. */ + if (is_link && strstr (file_name, ".so") != NULL) + return 1; + error (0, 0, _("Input file %s not found.\n"), file_name); + return 1; + } + + if (fstat64 (fileno (file), &statbuf) < 0) + { + error (0, 0, _("Cannot fstat file %s.\n"), file_name); + fclose (file); + return 1; + } + + /* Check that the file is large enough so that we can access the + information. We're only checking the size of the headers here. */ + if ((size_t) statbuf.st_size < sizeof (struct exec) + || (size_t) statbuf.st_size < sizeof (ElfW(Ehdr))) + { + if (statbuf.st_size == 0) + error (0, 0, _("File %s is empty, not checked."), file_name); + else + { + char buf[SELFMAG]; + size_t n = MIN (statbuf.st_size, SELFMAG); + if (fread (buf, n, 1, file) == 1 && memcmp (buf, ELFMAG, n) == 0) + error (0, 0, _("File %s is too small, not checked."), file_name); + } + fclose (file); + return 1; + } + + file_contents = mmap (0, statbuf.st_size, PROT_READ, MAP_SHARED, + fileno (file), 0); + if (file_contents == MAP_FAILED) + { + error (0, 0, _("Cannot mmap file %s.\n"), file_name); + fclose (file); + return 1; + } + + /* First check if this is an aout file. */ + aout_header = (struct exec *) file_contents; + if (N_MAGIC (*aout_header) == ZMAGIC +#ifdef QMAGIC /* Linuxism. */ + || N_MAGIC (*aout_header) == QMAGIC +#endif + ) + { + /* Aout files don't have a soname, just return the name + including the major number. */ + char *copy, *major, *dot; + copy = xstrdup (lib); + major = strstr (copy, ".so."); + if (major) + { + dot = strstr (major + 4, "."); + if (dot) + *dot = '\0'; + } + *soname = copy; + *flag = FLAG_LIBC4; + goto done; + } + + elf_header = (ElfW(Ehdr) *) file_contents; + if (memcmp (elf_header->e_ident, ELFMAG, SELFMAG) != 0) + { + /* The file is neither ELF nor aout. Check if it's a linker + script, like libc.so - otherwise complain. Only search the + beginning of the file. */ + size_t len = MIN (statbuf.st_size, 512); + if (memmem (file_contents, len, "GROUP", 5) == NULL + && memmem (file_contents, len, "GNU ld script", 13) == NULL + && !is_gdb_python_file (file_name)) + error (0, 0, _("%s is not an ELF file - it has the wrong magic bytes at the start.\n"), + file_name); + ret = 1; + } + /* Libraries have to be shared object files. */ + else if (elf_header->e_type != ET_DYN) + ret = 1; + else if (process_elf_file (file_name, lib, flag, osversion, soname, + file_contents, statbuf.st_size)) + ret = 1; + + done: + /* Clean up allocated memory and resources. */ + munmap (file_contents, statbuf.st_size); + fclose (file); + + *stat_buf = statbuf; + return ret; +} + +/* Returns made up soname if lib doesn't have explicit DT_SONAME. */ + +char * +implicit_soname (const char *lib, int flag) +{ + char *soname = xstrdup (lib); + + if ((flag & FLAG_TYPE_MASK) != FLAG_LIBC4) + return soname; + + /* Aout files don't have a soname, just return the name + including the major number. */ + char *major = strstr (soname, ".so."); + if (major) + { + char *dot = strstr (major + 4, "."); + if (dot) + *dot = '\0'; + } + return soname; +} + +/* Get architecture specific version of process_elf_file. */ +#include <readelflib.c> |