diff options
Diffstat (limited to 'src/strip.c')
| -rw-r--r-- | src/strip.c | 1769 |
1 files changed, 0 insertions, 1769 deletions
diff --git a/src/strip.c b/src/strip.c deleted file mode 100644 index e5c4289c..00000000 --- a/src/strip.c +++ /dev/null @@ -1,1769 +0,0 @@ -/* Discard section not used at runtime from object files. - Copyright (C) 2000, 2001, 2002, 2003, 2004 Red Hat, Inc. - Written by Ulrich Drepper <drepper@redhat.com>, 2000. - - This program is Open Source software; you can redistribute it and/or - modify it under the terms of the Open Software License version 1.0 as - published by the Open Source Initiative. - - You should have received a copy of the Open Software License along - with this program; if not, you may obtain a copy of the Open Software - License version 1.0 from http://www.opensource.org/licenses/osl.php or - by writing the Open Source Initiative c/o Lawrence Rosen, Esq., - 3001 King Ranch Road, Ukiah, CA 95482. */ - -#ifdef HAVE_CONFIG_H -# include <config.h> -#endif - -#include <argp.h> -#include <assert.h> -#include <byteswap.h> -#include <endian.h> -#include <error.h> -#include <fcntl.h> -#include <gelf.h> -#include <libelf.h> -#include <libintl.h> -#include <locale.h> -#include <mcheck.h> -#include <stdbool.h> -#include <stdio.h> -#include <stdio_ext.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include <sys/param.h> -#include <sys/time.h> - -#include <elf-knowledge.h> -#include <libebl.h> -#include <system.h> - - -/* Name and version of program. */ -static void print_version (FILE *stream, struct argp_state *state); -void (*argp_program_version_hook) (FILE *, struct argp_state *) = print_version; - - -/* Values for the parameters which have no short form. */ -#define OPT_REMOVE_COMMENT 0x100 -#define OPT_PERMISSIVE 0x101 - - -/* Definitions of arguments for argp functions. */ -static const struct argp_option options[] = -{ - { NULL, 0, NULL, 0, N_("Output selection:") }, - { NULL, 'o', "FILE", 0, N_("Place stripped output into FILE") }, - { NULL, 'f', "FILE", 0, N_("Extract the removed sections into FILE") }, - - { NULL, 0, NULL, 0, N_("Output options:") }, - { "strip-debug", 'g', NULL, 0, N_("Remove all debugging symbols") }, - { "preserve-dates", 'p', NULL, 0, - N_("Copy modified/access timestamps to the output") }, - { "remove-comment", OPT_REMOVE_COMMENT, NULL, 0, - N_("Remove .comment section") }, - { "permissive", OPT_PERMISSIVE, NULL, 0, - N_("Relax a few rules to handle slightly broken ELF files") }, - { NULL, 0, NULL, 0, NULL } -}; - -/* Short description of program. */ -static const char doc[] = N_("Discard symbols from object files."); - -/* Strings for arguments in help texts. */ -static const char args_doc[] = N_("[FILE...]"); - -/* Prototype for option handler. */ -static error_t parse_opt (int key, char *arg, struct argp_state *state); - -/* Function to print some extra text in the help message. */ -static char *more_help (int key, const char *text, void *input); - -/* Data structure to communicate with argp functions. */ -static struct argp argp = -{ - options, parse_opt, args_doc, doc, NULL, more_help -}; - - -/* Print symbols in file named FNAME. */ -static int process_file (const char *fname); - -/* Handle one ELF file. */ -static int handle_elf (int fd, Elf *elf, const char *prefix, - const char *fname, mode_t mode, struct timeval tvp[2]); - -/* Handle all files contained in the archive. */ -static int handle_ar (int fd, Elf *elf, const char *prefix, const char *fname, - struct timeval tvp[2]); - -#define INTERNAL_ERROR(fname) \ - error (EXIT_FAILURE, 0, gettext ("%s: INTERNAL ERROR %d (%s-%s): %s"), \ - fname, __LINE__, VERSION, __DATE__, elf_errmsg (-1)) - - -/* Name of the output file. */ -static const char *output_fname; - -/* Name of the debug output file. */ -static const char *debug_fname; - -/* If true output files shall have same date as the input file. */ -static bool preserve_dates; - -/* If true .comment sections will be removed. */ -static bool remove_comment; - -/* If true remove all debug sections. */ -static bool remove_debug; - -/* If true relax some ELF rules for input files. */ -static bool permissive; - - -int -main (int argc, char *argv[]) -{ - int remaining; - int result = 0; - - /* Make memory leak detection possible. */ - mtrace (); - - /* We use no threads here which can interfere with handling a stream. */ - __fsetlocking (stdin, FSETLOCKING_BYCALLER); - __fsetlocking (stdout, FSETLOCKING_BYCALLER); - __fsetlocking (stderr, FSETLOCKING_BYCALLER); - - /* Set locale. */ - setlocale (LC_ALL, ""); - - /* Make sure the message catalog can be found. */ - bindtextdomain (PACKAGE, LOCALEDIR); - - /* Initialize the message catalog. */ - textdomain (PACKAGE); - - /* Parse and process arguments. */ - argp_parse (&argp, argc, argv, 0, &remaining, NULL); - - /* Tell the library which version we are expecting. */ - elf_version (EV_CURRENT); - - if (remaining == argc) - /* The user didn't specify a name so we use a.out. */ - result = process_file ("a.out"); - else - { - /* If we have seen the `-o' or '-f' option there must be exactly one - input file. */ - if ((output_fname != NULL || debug_fname != NULL) - && remaining + 1 < argc) - error (EXIT_FAILURE, 0, gettext ("\ -Only one input file allowed together with '-o' and '-f'")); - - /* Process all the remaining files. */ - do - result |= process_file (argv[remaining]); - while (++remaining < argc); - } - - return result; -} - - -/* Print the version information. */ -static void -print_version (FILE *stream, struct argp_state *state) -{ - fprintf (stream, "strip (%s) %s\n", PACKAGE_NAME, VERSION); - fprintf (stream, gettext ("\ -Copyright (C) %s Red Hat, Inc.\n\ -This is free software; see the source for copying conditions. There is NO\n\ -warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n\ -"), "2004"); - fprintf (stream, gettext ("Written by %s.\n"), "Ulrich Drepper"); -} - - -/* Handle program arguments. */ -static error_t -parse_opt (int key, char *arg, struct argp_state *state) -{ - switch (key) - { - case 'f': - debug_fname = arg; - break; - - case 'o': - output_fname = arg; - break; - - case 'p': - preserve_dates = true; - break; - - case OPT_REMOVE_COMMENT: - remove_comment = true; - break; - - case 'g': - remove_debug = true; - break; - - case OPT_PERMISSIVE: - permissive = true; - break; - - default: - return ARGP_ERR_UNKNOWN; - } - return 0; -} - - -static char * -more_help (int key, const char *text, void *input) -{ - char *buf; - - switch (key) - { - case ARGP_KEY_HELP_EXTRA: - /* We print some extra information. */ - if (asprintf (&buf, gettext ("Please report bugs to %s.\n"), - PACKAGE_BUGREPORT) < 0) - buf = NULL; - return buf; - - default: - break; - } - return (char *) text; -} - - -static int -process_file (const char *fname) -{ - /* If we have to preserve the modify and access timestamps get them - now. We cannot use fstat() after opening the file since the open - would change the access time. */ - struct stat64 pre_st; - struct timeval tv[2]; - again: - if (preserve_dates) - { - if (stat64 (fname, &pre_st) != 0) - { - error (0, errno, gettext ("cannot stat input file \"%s\""), fname); - return 1; - } - - /* If we have to preserve the timestamp, we need it in the - format utimes() understands. */ - TIMESPEC_TO_TIMEVAL (&tv[0], &pre_st.st_atim); - TIMESPEC_TO_TIMEVAL (&tv[1], &pre_st.st_mtim); - } - - /* Open the file. */ - int fd = open (fname, O_RDWR); - if (fd == -1) - { - error (0, errno, gettext ("while opening \"%s\""), fname); - return 1; - } - - /* We always use fstat() even if we called stat() before. This is - done to make sure the information returned by stat() is for the - same file. */ - struct stat64 st; - if (fstat64 (fd, &st) != 0) - { - error (0, errno, gettext ("cannot stat input file \"%s\""), fname); - return 1; - } - /* Paranoid mode on. */ - if (preserve_dates - && (st.st_ino != pre_st.st_ino || st.st_dev != pre_st.st_dev)) - { - /* We detected a race. Try again. */ - close (fd); - goto again; - } - - /* Now get the ELF descriptor. */ - Elf *elf = elf_begin (fd, ELF_C_RDWR, NULL); - int result; - switch (elf_kind (elf)) - { - case ELF_K_ELF: - result = handle_elf (fd, elf, NULL, fname, st.st_mode & ACCESSPERMS, - preserve_dates ? tv : NULL); - break; - - case ELF_K_AR: - /* It is not possible to strip the content of an archive direct - the output to a specific file. */ - if (unlikely (output_fname != NULL)) - { - error (0, 0, gettext ("%s: cannot use -o when stripping archive"), - fname); - result = 1; - } - else - result = handle_ar (fd, elf, NULL, fname, preserve_dates ? tv : NULL); - break; - - default: - error (0, 0, gettext ("%s: File format not recognized"), fname); - result = 1; - break; - } - - if (unlikely (elf_end (elf) != 0)) - INTERNAL_ERROR (fname); - - close (fd); - - return result; -} - - -/* Maximum size of array allocated on stack. */ -#define MAX_STACK_ALLOC (400 * 1024) - - -static uint32_t -crc32_file (int fd, uint32_t *resp) -{ - unsigned char buffer[1024 * 8]; - uint32_t crc = 0; - ssize_t count; - - /* We have to rewind. */ - if (lseek (fd, 0, SEEK_SET) < 0) - return 1; - - while ((count = TEMP_FAILURE_RETRY (read (fd, buffer, sizeof (buffer)))) > 0) - crc = crc32 (crc, buffer, count); - - *resp = crc; - - return count != 0; -} - - -static int -handle_elf (int fd, Elf *elf, const char *prefix, const char *fname, - mode_t mode, struct timeval tvp[2]) -{ - size_t prefix_len = prefix == NULL ? 0 : strlen (prefix); - size_t fname_len = strlen (fname) + 1; - char *fullname = alloca (prefix_len + 1 + fname_len); - char *cp = fullname; - Elf *newelf; - Elf *debugelf = NULL; - char *tmp_debug_fname = NULL; - int result = 0; - GElf_Ehdr ehdr_mem; - GElf_Ehdr *ehdr; - size_t shstrndx; - size_t shnum; - struct shdr_info - { - Elf_Scn *scn; - GElf_Shdr shdr; - Elf_Data *data; - const char *name; - Elf32_Word idx; /* Index in new file. */ - Elf32_Word old_sh_link; /* Original value of shdr.sh_link. */ - Elf32_Word symtab_idx; - Elf32_Word version_idx; - Elf32_Word group_idx; - Elf32_Word group_cnt; - Elf_Scn *newscn; - struct Ebl_Strent *se; - Elf32_Word *newsymidx; - } *shdr_info = NULL; - Elf_Scn *scn; - size_t cnt; - size_t idx; - bool changes; - GElf_Ehdr newehdr_mem; - GElf_Ehdr *newehdr; - GElf_Ehdr debugehdr_mem; - GElf_Ehdr *debugehdr; - struct Ebl_Strtab *shst = NULL; - uint32_t debug_crc; - bool any_symtab_changes = false; - Elf_Data *shstrtab_data = NULL; - - /* Create the full name of the file. */ - if (prefix != NULL) - { - cp = mempcpy (cp, prefix, prefix_len); - *cp++ = ':'; - } - memcpy (cp, fname, fname_len); - - /* If we are not replacing the input file open a new file here. */ - if (output_fname != NULL) - { - fd = open (output_fname, O_RDWR | O_CREAT, mode); - if (unlikely (fd == -1)) - { - error (0, errno, gettext ("cannot open `%s'"), output_fname); - return 1; - } - } - - int debug_fd = -1; - - /* Get the EBL handling. The -g option is currently the only reason - we need EBL so dont open the backend unless necessary. */ - Ebl *ebl = NULL; - if (remove_debug) - { - ebl = ebl_openbackend (elf); - if (ebl == NULL) - { - error (0, errno, gettext ("cannot open EBL backend")); - result = 1; - goto fail; - } - } - - /* Open the additional file the debug information will be stored in. */ - if (debug_fname != NULL) - { - /* Create a temporary file name. We do not want to overwrite - the debug file if the file would not contain any - information. */ - size_t debug_fname_len = strlen (debug_fname); - tmp_debug_fname = (char *) alloca (debug_fname_len + sizeof (".XXXXXX")); - strcpy (mempcpy (tmp_debug_fname, debug_fname, debug_fname_len), - ".XXXXXX"); - - debug_fd = mkstemp (tmp_debug_fname); - if (unlikely (debug_fd == -1)) - { - error (0, errno, gettext ("cannot open `%s'"), debug_fname); - result = 1; - goto fail; - } - } - - /* Get the information from the old file. */ - ehdr = gelf_getehdr (elf, &ehdr_mem); - if (ehdr == NULL) - INTERNAL_ERROR (fname); - - /* Get the section header string table index. */ - if (unlikely (elf_getshstrndx (elf, &shstrndx) < 0)) - error (EXIT_FAILURE, 0, - gettext ("cannot get section header string table index")); - - /* We now create a new ELF descriptor for the same file. We - construct it almost exactly in the same way with some information - dropped. */ - if (output_fname != NULL) - newelf = elf_begin (fd, ELF_C_WRITE_MMAP, NULL); - else - newelf = elf_clone (elf, ELF_C_EMPTY); - - if (unlikely (gelf_newehdr (newelf, gelf_getclass (elf)) == 0) - || (ehdr->e_type != ET_REL - && unlikely (gelf_newphdr (newelf, ehdr->e_phnum) == 0))) - { - error (0, 0, gettext ("cannot create new file `%s': %s"), - output_fname, elf_errmsg (-1)); - goto fail; - } - - /* Copy over the old program header if needed. */ - if (ehdr->e_type != ET_REL) - for (cnt = 0; cnt < ehdr->e_phnum; ++cnt) - { - GElf_Phdr phdr_mem; - GElf_Phdr *phdr; - - phdr = gelf_getphdr (elf, cnt, &phdr_mem); - if (phdr == NULL - || unlikely (gelf_update_phdr (newelf, cnt, phdr) == 0)) - INTERNAL_ERROR (fname); - } - - if (debug_fname != NULL) - { - /* Also create an ELF descriptor for the debug file */ - debugelf = elf_begin (debug_fd, ELF_C_WRITE_MMAP, NULL); - if (unlikely (gelf_newehdr (debugelf, gelf_getclass (elf)) == 0) - || (ehdr->e_type != ET_REL - && unlikely (gelf_newphdr (debugelf, ehdr->e_phnum) == 0))) - { - error (0, 0, gettext ("cannot create new file `%s': %s"), - debug_fname, elf_errmsg (-1)); - goto fail_close; - } - - /* Copy over the old program header if needed. */ - if (ehdr->e_type != ET_REL) - for (cnt = 0; cnt < ehdr->e_phnum; ++cnt) - { - GElf_Phdr phdr_mem; - GElf_Phdr *phdr; - - phdr = gelf_getphdr (elf, cnt, &phdr_mem); - if (phdr == NULL - || unlikely (gelf_update_phdr (debugelf, cnt, phdr) == 0)) - INTERNAL_ERROR (fname); - } - } - - /* Number of sections. */ - if (unlikely (elf_getshnum (elf, &shnum) < 0)) - { - error (0, 0, gettext ("cannot determine number of sections: %s"), - elf_errmsg (-1)); - goto fail_close; - } - - /* Storage for section information. We leave room for two more - entries since we unconditionally create a section header string - table. Maybe some weird tool created an ELF file without one. - The other one is used for the debug link section. */ - if ((shnum + 2) * sizeof (struct shdr_info) > MAX_STACK_ALLOC) - shdr_info = (struct shdr_info *) xcalloc (shnum + 2, - sizeof (struct shdr_info)); - else - { - shdr_info = (struct shdr_info *) alloca ((shnum + 2) - * sizeof (struct shdr_info)); - memset (shdr_info, '\0', (shnum + 2) * sizeof (struct shdr_info)); - } - - /* Prepare section information data structure. */ - scn = NULL; - cnt = 1; - while ((scn = elf_nextscn (elf, scn)) != NULL) - { - /* This should always be true (i.e., there should not be any - holes in the numbering). */ - assert (elf_ndxscn (scn) == cnt); - - shdr_info[cnt].scn = scn; - - /* Get the header. */ - if (gelf_getshdr (scn, &shdr_info[cnt].shdr) == NULL) - INTERNAL_ERROR (fname); - - /* Get the name of the section. */ - shdr_info[cnt].name = elf_strptr (elf, shstrndx, - shdr_info[cnt].shdr.sh_name); - if (shdr_info[cnt].name == NULL) - { - error (0, 0, gettext ("illformed file `%s'"), fname); - goto fail_close; - } - - /* Mark them as present but not yet investigated. */ - shdr_info[cnt].idx = 1; - - /* Remember the shdr.sh_link value. */ - shdr_info[cnt].old_sh_link = shdr_info[cnt].shdr.sh_link; - - /* Sections in files other than relocatable object files which - are not loaded can be freely moved by us. In relocatable - object files everything can be moved. */ - if (ehdr->e_type == ET_REL - || (shdr_info[cnt].shdr.sh_flags & SHF_ALLOC) == 0) - shdr_info[cnt].shdr.sh_offset = 0; - - /* If this is an extended section index table store an - appropriate reference. */ - if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB_SHNDX)) - { - assert (shdr_info[shdr_info[cnt].shdr.sh_link].symtab_idx == 0); - shdr_info[shdr_info[cnt].shdr.sh_link].symtab_idx = cnt; - } - else if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_GROUP)) - { - Elf32_Word *grpref; - size_t inner; - - /* Cross-reference the sections contained in the section - group. */ - shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL); - if (shdr_info[cnt].data == NULL) - INTERNAL_ERROR (fname); - - /* XXX Fix for unaligned access. */ - grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf; - for (inner = 1; - inner < shdr_info[cnt].data->d_size / sizeof (Elf32_Word); - ++inner) - shdr_info[grpref[inner]].group_idx = cnt; - - if (inner == 1 || (inner == 2 && (grpref[0] & GRP_COMDAT) == 0)) - /* If the section group contains only one element and this - is n COMDAT section we can drop it right away. */ - shdr_info[cnt].idx = 0; - else - shdr_info[cnt].group_cnt = inner - 1; - } - else if (unlikely (shdr_info[cnt].shdr.sh_type == SHT_GNU_versym)) - { - assert (shdr_info[shdr_info[cnt].shdr.sh_link].version_idx == 0); - shdr_info[shdr_info[cnt].shdr.sh_link].version_idx = cnt; - } - - /* If this section is part of a group make sure it is not - discarded right away. */ - if ((shdr_info[cnt].shdr.sh_flags & SHF_GROUP) != 0) - { - assert (shdr_info[cnt].group_idx != 0); - - if (shdr_info[shdr_info[cnt].group_idx].idx == 0) - { - /* The section group section will be removed. */ - shdr_info[cnt].group_idx = 0; - shdr_info[cnt].shdr.sh_flags &= ~SHF_GROUP; - } - } - - /* Increment the counter. */ - ++cnt; - } - - /* Now determine which sections can go away. The general rule is that - all sections which are not used at runtime are stripped out. But - there are a few exceptions: - - - special sections named ".comment" and ".note" are kept - - OS or architecture specific sections are kept since we might not - know how to handle them - - if a section is referred to from a section which is not removed - in the sh_link or sh_info element it cannot be removed either - */ - for (cnt = 1; cnt < shnum; ++cnt) - /* Check whether the section can be removed. */ - if (SECTION_STRIP_P (ebl, elf, ehdr, &shdr_info[cnt].shdr, - shdr_info[cnt].name, remove_comment, remove_debug)) - { - /* For now assume this section will be removed. */ - shdr_info[cnt].idx = 0; - - idx = shdr_info[cnt].group_idx; - while (idx != 0) - { - /* If the references section group is a normal section - group and has one element remaining, or if it is an - empty COMDAT section group it is removed. */ - bool is_comdat; - - /* The section group data is already loaded. */ - assert (shdr_info[idx].data != NULL); - - is_comdat = (((Elf32_Word *) shdr_info[idx].data->d_buf)[0] - & GRP_COMDAT) != 0; - - --shdr_info[idx].group_cnt; - if ((!is_comdat && shdr_info[idx].group_cnt == 1) - || (is_comdat && shdr_info[idx].group_cnt == 0)) - { - shdr_info[idx].idx = 0; - /* Continue recursively. */ - idx = shdr_info[idx].group_idx; - } - else - break; - } - } - - /* Mark the SHT_NULL section as handled. */ - shdr_info[0].idx = 2; - - - /* Handle exceptions: section groups and cross-references. We might - have to repeat this a few times since the resetting of the flag - might propagate. */ - do - { - changes = false; - - for (cnt = 1; cnt < shnum; ++cnt) - { - if (shdr_info[cnt].idx == 0) - { - /* If a relocation section is marked as being removed make - sure the section it is relocating is removed, too. */ - if ((shdr_info[cnt].shdr.sh_type == SHT_REL - || shdr_info[cnt].shdr.sh_type == SHT_RELA) - && shdr_info[shdr_info[cnt].shdr.sh_info].idx != 0) - shdr_info[cnt].idx = 1; - } - - if (shdr_info[cnt].idx == 1) - { - /* The content of symbol tables we don't remove must not - reference any section which we do remove. Otherwise - we cannot remove the section. */ - if (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM - || shdr_info[cnt].shdr.sh_type == SHT_SYMTAB) - { - Elf_Data *symdata; - Elf_Data *xndxdata; - size_t elsize; - - /* Make sure the data is loaded. */ - if (shdr_info[cnt].data == NULL) - { - shdr_info[cnt].data - = elf_getdata (shdr_info[cnt].scn, NULL); - if (shdr_info[cnt].data == NULL) - INTERNAL_ERROR (fname); - } - symdata = shdr_info[cnt].data; - - /* If there is an extended section index table load it - as well. */ - if (shdr_info[cnt].symtab_idx != 0 - && shdr_info[shdr_info[cnt].symtab_idx].data == NULL) - { - assert (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB); - - shdr_info[shdr_info[cnt].symtab_idx].data - = elf_getdata (shdr_info[shdr_info[cnt].symtab_idx].scn, - NULL); - if (shdr_info[shdr_info[cnt].symtab_idx].data == NULL) - INTERNAL_ERROR (fname); - } - xndxdata = shdr_info[shdr_info[cnt].symtab_idx].data; - - /* Go through all symbols and make sure the section they - reference is not removed. */ - elsize = gelf_fsize (elf, ELF_T_SYM, 1, ehdr->e_version); - - for (size_t inner = 0; - inner < shdr_info[cnt].data->d_size / elsize; - ++inner) - { - GElf_Sym sym_mem; - Elf32_Word xndx; - GElf_Sym *sym; - size_t scnidx; - - sym = gelf_getsymshndx (symdata, xndxdata, inner, - &sym_mem, &xndx); - if (sym == NULL) - INTERNAL_ERROR (fname); - - scnidx = sym->st_shndx; - if (scnidx == SHN_UNDEF || scnidx >= shnum - || (scnidx >= SHN_LORESERVE - && scnidx <= SHN_HIRESERVE - && scnidx != SHN_XINDEX) - /* Don't count in the section symbols. */ - || GELF_ST_TYPE (sym->st_info) == STT_SECTION) - /* This is no section index, leave it alone. */ - continue; - else if (scnidx == SHN_XINDEX) - scnidx = xndx; - - if (shdr_info[scnidx].idx == 0) - { - /* Mark this section as used. */ - shdr_info[scnidx].idx = 1; - changes |= scnidx < cnt; - } - } - } - - /* Cross referencing happens: - - for the cases the ELF specification says. That are - + SHT_DYNAMIC in sh_link to string table - + SHT_HASH in sh_link to symbol table - + SHT_REL and SHT_RELA in sh_link to symbol table - + SHT_SYMTAB and SHT_DYNSYM in sh_link to string table - + SHT_GROUP in sh_link to symbol table - + SHT_SYMTAB_SHNDX in sh_link to symbol table - Other (OS or architecture-specific) sections might as - well use this field so we process it unconditionally. - - references inside section groups - - specially marked references in sh_info if the SHF_INFO_LINK - flag is set - */ - - if (shdr_info[shdr_info[cnt].shdr.sh_link].idx == 0) - { - shdr_info[shdr_info[cnt].shdr.sh_link].idx = 1; - changes |= shdr_info[cnt].shdr.sh_link < cnt; - } - - /* Handle references through sh_info. */ - if (SH_INFO_LINK_P (&shdr_info[cnt].shdr) - && shdr_info[shdr_info[cnt].shdr.sh_info].idx == 0) - { - shdr_info[shdr_info[cnt].shdr.sh_info].idx = 1; - changes |= shdr_info[cnt].shdr.sh_info < cnt; - } - - /* Mark the section as investigated. */ - shdr_info[cnt].idx = 2; - } - } - } - while (changes); - - /* Write out a copy of all the sections to the debug output file. - The ones that are not removed in the stripped file are SHT_NOBITS */ - if (debug_fname != NULL) - { - for (cnt = 1; cnt < shnum; ++cnt) - { - Elf_Data *debugdata; - GElf_Shdr debugshdr; - int discard_section; - - scn = elf_newscn (debugelf); - if (scn == NULL) - error (EXIT_FAILURE, 0, - gettext ("while generating output file: %s"), - elf_errmsg (-1)); - - discard_section = shdr_info[cnt].idx > 0 && cnt != ehdr->e_shstrndx; - - /* Set the section header in the new file. */ - debugshdr = shdr_info[cnt].shdr; - if (discard_section) - debugshdr.sh_type = SHT_NOBITS; - - if (unlikely (gelf_update_shdr (scn, &debugshdr)) == 0) - /* There cannot be any overflows. */ - INTERNAL_ERROR (fname); - - /* Get the data from the old file if necessary. */ - if (shdr_info[cnt].data == NULL) - { - shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL); - if (shdr_info[cnt].data == NULL) - INTERNAL_ERROR (fname); - } - - /* Set the data. This is done by copying from the old file. */ - debugdata = elf_newdata (scn); - if (debugdata == NULL) - INTERNAL_ERROR (fname); - - /* Copy the structure. */ - *debugdata = *shdr_info[cnt].data; - if (discard_section) - debugdata->d_buf = NULL; - } - - /* Finish the ELF header. Fill in the fields not handled by - libelf from the old file. */ - debugehdr = gelf_getehdr (debugelf, &debugehdr_mem); - if (debugehdr == NULL) - INTERNAL_ERROR (fname); - - memcpy (debugehdr->e_ident, ehdr->e_ident, EI_NIDENT); - debugehdr->e_type = ehdr->e_type; - debugehdr->e_machine = ehdr->e_machine; - debugehdr->e_version = ehdr->e_version; - debugehdr->e_entry = ehdr->e_entry; - debugehdr->e_flags = ehdr->e_flags; - debugehdr->e_shstrndx = ehdr->e_shstrndx; - - if (unlikely (gelf_update_ehdr (debugelf, debugehdr)) == 0) - { - error (0, 0, gettext ("%s: error while creating ELF header: %s"), - debug_fname, elf_errmsg (-1)); - result = 1; - goto fail_close; - } - - /* Finally write the file. */ - if (unlikely (elf_update (debugelf, ELF_C_WRITE)) == -1) - { - error (0, 0, gettext ("while writing `%s': %s"), - debug_fname, elf_errmsg (-1)); - result = 1; - goto fail_close; - } - - /* Create the real output file. First rename, then change the - mode. */ - if (rename (tmp_debug_fname, debug_fname) != 0 - || fchmod (debug_fd, mode) != 0) - { - error (0, errno, gettext ("while creating '%s'"), debug_fname); - result = 1; - goto fail_close; - } - - /* The temporary file does not exist anymore. */ - tmp_debug_fname = NULL; - - /* Compute the checksum which we will add to the executable. */ - if (crc32_file (debug_fd, &debug_crc) != 0) - { - error (0, errno, - gettext ("while computing checksum for debug information")); - unlink (debug_fname); - result = 1; - goto fail_close; - } - - } - - /* Mark the section header string table as unused, we will create - a new one. */ - shdr_info[shstrndx].idx = 0; - - /* We need a string table for the section headers. */ - shst = ebl_strtabinit (true); - if (shst == NULL) - error (EXIT_FAILURE, errno, gettext ("while preparing output for `%s'"), - output_fname ?: fname); - - /* Assign new section numbers. */ - shdr_info[0].idx = 0; - for (cnt = idx = 1; cnt < shnum; ++cnt) - if (shdr_info[cnt].idx > 0) - { - shdr_info[cnt].idx = idx++; - - /* Create a new section. */ - shdr_info[cnt].newscn = elf_newscn (newelf); - if (shdr_info[cnt].newscn == NULL) - error (EXIT_FAILURE, 0, gettext ("while generating output file: %s"), - elf_errmsg (-1)); - - assert (elf_ndxscn (shdr_info[cnt].newscn) == shdr_info[cnt].idx); - - /* Add this name to the section header string table. */ - shdr_info[cnt].se = ebl_strtabadd (shst, shdr_info[cnt].name, 0); - } - - /* Test whether we are doing anything at all. */ - if (cnt == idx) - /* Nope, all removable sections are already gone. */ - goto fail_close; - - /* Create the reference to the file with the debug info. */ - if (debug_fname != NULL) - { - char *debug_basename; - off_t crc_offset; - - /* Add the section header string table section name. */ - shdr_info[cnt].se = ebl_strtabadd (shst, ".gnu_debuglink", 15); - shdr_info[cnt].idx = idx++; - - /* Create the section header. */ - shdr_info[cnt].shdr.sh_type = SHT_PROGBITS; - shdr_info[cnt].shdr.sh_flags = 0; - shdr_info[cnt].shdr.sh_addr = 0; - shdr_info[cnt].shdr.sh_link = SHN_UNDEF; - shdr_info[cnt].shdr.sh_info = SHN_UNDEF; - shdr_info[cnt].shdr.sh_entsize = 0; - shdr_info[cnt].shdr.sh_addralign = 4; - /* We set the offset to zero here. Before we write the ELF file the - field must have the correct value. This is done in the final - loop over all section. Then we have all the information needed. */ - shdr_info[cnt].shdr.sh_offset = 0; - - /* Create the section. */ - shdr_info[cnt].newscn = elf_newscn (newelf); - if (shdr_info[cnt].newscn == NULL) - error (EXIT_FAILURE, 0, - gettext ("while create section header section: %s"), - elf_errmsg (-1)); - assert (elf_ndxscn (shdr_info[cnt].newscn) == shdr_info[cnt].idx); - - shdr_info[cnt].data = elf_newdata (shdr_info[cnt].newscn); - if (shdr_info[cnt].data == NULL) - error (EXIT_FAILURE, 0, gettext ("cannot allocate section data: %s"), - elf_errmsg (-1)); - - debug_basename = basename (debug_fname); - crc_offset = strlen (debug_basename) + 1; - /* Align to 4 byte boundary */ - crc_offset = ((crc_offset - 1) & ~3) + 4; - - shdr_info[cnt].data->d_align = 4; - shdr_info[cnt].shdr.sh_size = shdr_info[cnt].data->d_size - = crc_offset + 4; - shdr_info[cnt].data->d_buf = xcalloc (1, shdr_info[cnt].data->d_size); - - strcpy (shdr_info[cnt].data->d_buf, debug_basename); - /* Store the crc value in the correct byteorder */ - if ((__BYTE_ORDER == __LITTLE_ENDIAN - && ehdr->e_ident[EI_DATA] == ELFDATA2MSB) - || (__BYTE_ORDER == __BIG_ENDIAN - && ehdr->e_ident[EI_DATA] == ELFDATA2LSB)) - debug_crc = bswap_32 (debug_crc); - memcpy ((char *)shdr_info[cnt].data->d_buf + crc_offset, - (char *) &debug_crc, 4); - - /* One more section done. */ - ++cnt; - } - - /* Index of the section header table in the shdr_info array. */ - size_t shdridx = cnt; - - /* Add the section header string table section name. */ - shdr_info[cnt].se = ebl_strtabadd (shst, ".shstrtab", 10); - shdr_info[cnt].idx = idx; - - /* Create the section header. */ - shdr_info[cnt].shdr.sh_type = SHT_STRTAB; - shdr_info[cnt].shdr.sh_flags = 0; - shdr_info[cnt].shdr.sh_addr = 0; - shdr_info[cnt].shdr.sh_link = SHN_UNDEF; - shdr_info[cnt].shdr.sh_info = SHN_UNDEF; - shdr_info[cnt].shdr.sh_entsize = 0; - /* We set the offset to zero here. Before we write the ELF file the - field must have the correct value. This is done in the final - loop over all section. Then we have all the information needed. */ - shdr_info[cnt].shdr.sh_offset = 0; - shdr_info[cnt].shdr.sh_addralign = 1; - - /* Create the section. */ - shdr_info[cnt].newscn = elf_newscn (newelf); - if (shdr_info[cnt].newscn == NULL) - error (EXIT_FAILURE, 0, - gettext ("while create section header section: %s"), - elf_errmsg (-1)); - assert (elf_ndxscn (shdr_info[cnt].newscn) == idx); - - /* Finalize the string table and fill in the correct indices in the - section headers. */ - shstrtab_data = elf_newdata (shdr_info[cnt].newscn); - if (shstrtab_data == NULL) - error (EXIT_FAILURE, 0, - gettext ("while create section header string table: %s"), - elf_errmsg (-1)); - ebl_strtabfinalize (shst, shstrtab_data); - - /* We have to set the section size. */ - shdr_info[cnt].shdr.sh_size = shstrtab_data->d_size; - - /* Update the section information. */ - GElf_Off lastoffset = 0; - for (cnt = 1; cnt <= shdridx; ++cnt) - if (shdr_info[cnt].idx > 0) - { - Elf_Data *newdata; - - scn = elf_getscn (newelf, shdr_info[cnt].idx); - assert (scn != NULL); - - /* Update the name. */ - shdr_info[cnt].shdr.sh_name = ebl_strtaboffset (shdr_info[cnt].se); - - /* Update the section header from the input file. Some fields - might be section indeces which now have to be adjusted. */ - if (shdr_info[cnt].shdr.sh_link != 0) - shdr_info[cnt].shdr.sh_link = - shdr_info[shdr_info[cnt].shdr.sh_link].idx; - - if (shdr_info[cnt].shdr.sh_type == SHT_GROUP) - { - assert (shdr_info[cnt].data != NULL); - - Elf32_Word *grpref = (Elf32_Word *) shdr_info[cnt].data->d_buf; - for (size_t inner = 0; - inner < shdr_info[cnt].data->d_size / sizeof (Elf32_Word); - ++inner) - grpref[inner] = shdr_info[grpref[inner]].idx; - } - - /* Handle the SHT_REL, SHT_RELA, and SHF_INFO_LINK flag. */ - if (SH_INFO_LINK_P (&shdr_info[cnt].shdr)) - shdr_info[cnt].shdr.sh_info = - shdr_info[shdr_info[cnt].shdr.sh_info].idx; - - /* Get the data from the old file if necessary. We already - created the data for the section header string table. */ - if (cnt < shnum) - { - if (shdr_info[cnt].data == NULL) - { - shdr_info[cnt].data = elf_getdata (shdr_info[cnt].scn, NULL); - if (shdr_info[cnt].data == NULL) - INTERNAL_ERROR (fname); - } - - /* Set the data. This is done by copying from the old file. */ - newdata = elf_newdata (scn); - if (newdata == NULL) - INTERNAL_ERROR (fname); - - /* Copy the structure. */ - *newdata = *shdr_info[cnt].data; - - /* We know the size. */ - shdr_info[cnt].shdr.sh_size = shdr_info[cnt].data->d_size; - - /* We have to adjust symtol tables. The st_shndx member might - have to be updated. */ - if (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM - || shdr_info[cnt].shdr.sh_type == SHT_SYMTAB) - { - Elf_Data *versiondata = NULL; - Elf_Data *shndxdata = NULL; - - size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, - ehdr->e_version); - - if (shdr_info[cnt].symtab_idx != 0) - { - assert (shdr_info[cnt].shdr.sh_type == SHT_SYMTAB_SHNDX); - /* This section has extended section information. - We have to modify that information, too. */ - shndxdata = elf_getdata (shdr_info[shdr_info[cnt].symtab_idx].scn, - NULL); - - assert ((versiondata->d_size / sizeof (Elf32_Word)) - >= shdr_info[cnt].data->d_size / elsize); - } - - if (shdr_info[cnt].version_idx != 0) - { - assert (shdr_info[cnt].shdr.sh_type == SHT_DYNSYM); - /* This section has associated version - information. We have to modify that - information, too. */ - versiondata = elf_getdata (shdr_info[shdr_info[cnt].version_idx].scn, - NULL); - - assert ((versiondata->d_size / sizeof (GElf_Versym)) - >= shdr_info[cnt].data->d_size / elsize); - } - - shdr_info[cnt].newsymidx - = (Elf32_Word *) xcalloc (shdr_info[cnt].data->d_size - / elsize, sizeof (Elf32_Word)); - - bool last_was_local = true; - size_t destidx; - size_t inner; - for (destidx = inner = 1; - inner < shdr_info[cnt].data->d_size / elsize; - ++inner) - { - Elf32_Word sec; - GElf_Sym sym_mem; - Elf32_Word xshndx; - GElf_Sym *sym = gelf_getsymshndx (shdr_info[cnt].data, - shndxdata, inner, - &sym_mem, &xshndx); - if (sym == NULL) - INTERNAL_ERROR (fname); - - if (sym->st_shndx == SHN_UNDEF - || (sym->st_shndx >= shnum - && sym->st_shndx != SHN_XINDEX)) - { - /* This is no section index, leave it alone - unless it is moved. */ - if (destidx != inner - && gelf_update_symshndx (shdr_info[cnt].data, - shndxdata, - destidx, sym, - xshndx) == 0) - INTERNAL_ERROR (fname); - - shdr_info[cnt].newsymidx[inner] = destidx++; - - if (last_was_local - && GELF_ST_BIND (sym->st_info) != STB_LOCAL) - { - last_was_local = false; - shdr_info[cnt].shdr.sh_info = destidx - 1; - } - - continue; - } - - /* Get the full section index, if necessary from the - XINDEX table. */ - if (sym->st_shndx != SHN_XINDEX) - sec = shdr_info[sym->st_shndx].idx; - else - { - assert (shndxdata != NULL); - - sec = shdr_info[xshndx].idx; - } - - if (sec != 0) - { - GElf_Section nshndx; - Elf32_Word nxshndx; - - if (sec < SHN_LORESERVE) - { - nshndx = sec; - nxshndx = 0; - } - else - { - nshndx = SHN_XINDEX; - nxshndx = sec; - } - - assert (sec < SHN_LORESERVE || shndxdata != NULL); - - if ((inner != destidx || nshndx != sym->st_shndx - || (shndxdata != NULL && nxshndx != xshndx)) - && (sym->st_shndx = nshndx, - gelf_update_symshndx (shdr_info[cnt].data, - shndxdata, - destidx, sym, - nxshndx) == 0)) - INTERNAL_ERROR (fname); - - shdr_info[cnt].newsymidx[inner] = destidx++; - - if (last_was_local - && GELF_ST_BIND (sym->st_info) != STB_LOCAL) - { - last_was_local = false; - shdr_info[cnt].shdr.sh_info = destidx - 1; - } - } - else - /* This is a section symbol for a section which has - been removed. */ - assert (GELF_ST_TYPE (sym->st_info) == STT_SECTION); - } - - if (destidx != inner) - { - /* The size of the symbol table changed. */ - shdr_info[cnt].shdr.sh_size = newdata->d_size - = destidx * elsize; - any_symtab_changes = true; - } - else - { - /* The symbol table didn't really change. */ - free (shdr_info[cnt].newsymidx); - shdr_info[cnt].newsymidx = NULL; - } - } - } - - /* If we have to, compute the offset of the section. */ - if (shdr_info[cnt].shdr.sh_offset == 0) - shdr_info[cnt].shdr.sh_offset - = ((lastoffset + shdr_info[cnt].shdr.sh_addralign - 1) - & ~((GElf_Off) (shdr_info[cnt].shdr.sh_addralign - 1))); - - /* Set the section header in the new file. */ - if (unlikely (gelf_update_shdr (scn, &shdr_info[cnt].shdr) == 0)) - /* There cannot be any overflows. */ - INTERNAL_ERROR (fname); - - /* Remember the last section written so far. */ - GElf_Off filesz = (shdr_info[cnt].shdr.sh_type != SHT_NOBITS - ? shdr_info[cnt].shdr.sh_size : 0); - if (lastoffset < shdr_info[cnt].shdr.sh_offset + filesz) - lastoffset = shdr_info[cnt].shdr.sh_offset + filesz; - } - - /* Adjust symbol references if symbol tables changed. */ - if (any_symtab_changes) - { - /* Find all relocation sections which use this - symbol table. */ - for (cnt = 1; cnt <= shdridx; ++cnt) - { - if (shdr_info[cnt].idx == 0) - /* Ignore sections which are discarded. */ - continue; - - if (shdr_info[cnt].shdr.sh_type == SHT_REL - || shdr_info[cnt].shdr.sh_type == SHT_RELA) - { - /* If the symbol table hasn't changed, do not do anything. */ - if (shdr_info[shdr_info[cnt].old_sh_link].newsymidx == NULL) - continue; - - Elf32_Word *newsymidx - = shdr_info[shdr_info[cnt].old_sh_link].newsymidx; - Elf_Data *d = elf_getdata (elf_getscn (newelf, - shdr_info[cnt].idx), - NULL); - assert (d != NULL); - size_t nrels = (shdr_info[cnt].shdr.sh_size - / shdr_info[cnt].shdr.sh_entsize); - - if (shdr_info[cnt].shdr.sh_type == SHT_REL) - for (size_t relidx = 0; relidx < nrels; ++relidx) - { - GElf_Rel rel_mem; - if (gelf_getrel (d, relidx, &rel_mem) == NULL) - INTERNAL_ERROR (fname); - - size_t symidx = GELF_R_SYM (rel_mem.r_info); - if (newsymidx[symidx] != symidx) - { - rel_mem.r_info - = GELF_R_INFO (newsymidx[symidx], - GELF_R_TYPE (rel_mem.r_info)); - - if (gelf_update_rel (d, relidx, &rel_mem) == 0) - INTERNAL_ERROR (fname); - } - } - else - for (size_t relidx = 0; relidx < nrels; ++relidx) - { - GElf_Rela rel_mem; - if (gelf_getrela (d, relidx, &rel_mem) == NULL) - INTERNAL_ERROR (fname); - - size_t symidx = GELF_R_SYM (rel_mem.r_info); - if (newsymidx[symidx] != symidx) - { - rel_mem.r_info - = GELF_R_INFO (newsymidx[symidx], - GELF_R_TYPE (rel_mem.r_info)); - - if (gelf_update_rela (d, relidx, &rel_mem) == 0) - INTERNAL_ERROR (fname); - } - } - } - else if (shdr_info[cnt].shdr.sh_type == SHT_HASH) - { - /* We have to recompute the hash table. */ - Elf32_Word symtabidx = shdr_info[cnt].old_sh_link; - - /* We do not have to do anything if the symbol table was - not changed. */ - if (shdr_info[symtabidx].newsymidx == NULL) - continue; - - /* The symbol version section in the new file. */ - scn = elf_getscn (newelf, shdr_info[cnt].idx); - - /* The symbol table data. */ - Elf_Data *symd = elf_getdata (elf_getscn (newelf, - shdr_info[symtabidx].idx), - NULL); - assert (symd != NULL); - - /* The hash table data. */ - Elf_Data *hashd = elf_getdata (scn, NULL); - assert (hashd != NULL); - - if (shdr_info[cnt].shdr.sh_entsize == sizeof (Elf32_Word)) - { - /* Sane arches first. */ - Elf32_Word *bucket = (Elf32_Word *) hashd->d_buf; - - size_t strshndx = shdr_info[symtabidx].old_sh_link; - size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, - ehdr->e_version); - - /* Convert to the correct byte order. */ - if (gelf_xlatetom (newelf, hashd, hashd, - BYTE_ORDER == LITTLE_ENDIAN - ? ELFDATA2LSB : ELFDATA2MSB) == NULL) - INTERNAL_ERROR (fname); - - /* Adjust the nchain value. The symbol table size - changed. We keep the same size for the bucket array. */ - bucket[1] = symd->d_size / elsize; - Elf32_Word nbucket = bucket[0]; - bucket += 2; - Elf32_Word *chain = bucket + nbucket; - - /* New size of the section. */ - GElf_Shdr shdr_mem; - GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); - shdr->sh_size = hashd->d_size - = (2 + symd->d_size / elsize + nbucket) - * sizeof (Elf32_Word); - (void) gelf_update_shdr (scn, shdr); - - /* Clear the arrays. */ - memset (bucket, '\0', - (symd->d_size / elsize + nbucket) - * sizeof (Elf32_Word)); - - for (size_t inner = shdr_info[symtabidx].shdr.sh_info; - inner < symd->d_size / elsize; ++inner) - { - GElf_Sym sym_mem; - GElf_Sym *sym = gelf_getsym (symd, inner, &sym_mem); - assert (sym != NULL); - - const char *name = elf_strptr (elf, strshndx, - sym->st_name); - assert (name != NULL); - size_t hidx = elf_hash (name) % nbucket; - - if (bucket[hidx] == 0) - bucket[hidx] = inner; - else - { - hidx = bucket[hidx]; - - while (chain[hidx] != 0) - hidx = chain[hidx]; - - chain[hidx] = inner; - } - } - } - else - { - /* Alpha and S390 64-bit use 64-bit SHT_HASH entries. */ - assert (shdr_info[cnt].shdr.sh_entsize - == sizeof (Elf64_Xword)); - - Elf64_Xword *bucket = (Elf64_Xword *) hashd->d_buf; - - size_t strshndx = shdr_info[symtabidx].old_sh_link; - size_t elsize = gelf_fsize (elf, ELF_T_SYM, 1, - ehdr->e_version); - - /* Convert to the correct byte order. */ - if (gelf_xlatetom (newelf, hashd, hashd, - BYTE_ORDER == LITTLE_ENDIAN - ? ELFDATA2LSB : ELFDATA2MSB) == NULL) - INTERNAL_ERROR (fname); - - /* Adjust the nchain value. The symbol table size - changed. We keep the same size for the bucket array. */ - bucket[1] = symd->d_size / elsize; - Elf64_Xword nbucket = bucket[0]; - bucket += 2; - Elf64_Xword *chain = bucket + nbucket; - - /* New size of the section. */ - GElf_Shdr shdr_mem; - GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); - shdr->sh_size = hashd->d_size - = (2 + symd->d_size / elsize + nbucket) - * sizeof (Elf64_Xword); - (void) gelf_update_shdr (scn, shdr); - - /* Clear the arrays. */ - memset (bucket, '\0', - (symd->d_size / elsize + nbucket) - * sizeof (Elf64_Xword)); - - for (size_t inner = shdr_info[symtabidx].shdr.sh_info; - inner < symd->d_size / elsize; ++inner) - { - GElf_Sym sym_mem; - GElf_Sym *sym = gelf_getsym (symd, inner, &sym_mem); - assert (sym != NULL); - - const char *name = elf_strptr (elf, strshndx, - sym->st_name); - assert (name != NULL); - size_t hidx = elf_hash (name) % nbucket; - - if (bucket[hidx] == 0) - bucket[hidx] = inner; - else - { - hidx = bucket[hidx]; - - while (chain[hidx] != 0) - hidx = chain[hidx]; - - chain[hidx] = inner; - } - } - } - - /* Convert back to the file byte order. */ - if (gelf_xlatetof (newelf, hashd, hashd, - BYTE_ORDER == LITTLE_ENDIAN - ? ELFDATA2LSB : ELFDATA2MSB) == NULL) - INTERNAL_ERROR (fname); - } - else if (shdr_info[cnt].shdr.sh_type == SHT_GNU_versym) - { - /* If the symbol table changed we have to adjust the - entries. */ - Elf32_Word symtabidx = shdr_info[cnt].old_sh_link; - - /* We do not have to do anything if the symbol table was - not changed. */ - if (shdr_info[symtabidx].newsymidx == NULL) - continue; - - /* The symbol version section in the new file. */ - scn = elf_getscn (newelf, shdr_info[cnt].idx); - - /* The symbol table data. */ - Elf_Data *symd = elf_getdata (elf_getscn (newelf, - shdr_info[symtabidx].idx), - NULL); - assert (symd != NULL); - - /* The version symbol data. */ - Elf_Data *verd = elf_getdata (scn, NULL); - assert (verd != NULL); - - /* Convert to the correct byte order. */ - if (gelf_xlatetom (newelf, verd, verd, - BYTE_ORDER == LITTLE_ENDIAN - ? ELFDATA2LSB : ELFDATA2MSB) == NULL) - INTERNAL_ERROR (fname); - - /* The symbol version array. */ - GElf_Half *verstab = (GElf_Half *) verd->d_buf; - - /* New indices of the symbols. */ - Elf32_Word *newsymidx = shdr_info[symtabidx].newsymidx; - - /* Walk through the list and */ - size_t elsize = gelf_fsize (elf, verd->d_type, 1, - ehdr->e_version); - for (size_t inner = 1; inner < verd->d_size / elsize; ++inner) - if (newsymidx[inner] != 0) - /* Overwriting the same array works since the - reordering can only move entries to lower indices - in the array. */ - verstab[newsymidx[inner]] = verstab[inner]; - - /* New size of the section. */ - GElf_Shdr shdr_mem; - GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); - shdr->sh_size = verd->d_size - = gelf_fsize (newelf, verd->d_type, - symd->d_size / gelf_fsize (elf, symd->d_type, 1, - ehdr->e_version), - ehdr->e_version); - (void) gelf_update_shdr (scn, shdr); - - /* Convert back to the file byte order. */ - if (gelf_xlatetof (newelf, verd, verd, - BYTE_ORDER == LITTLE_ENDIAN - ? ELFDATA2LSB : ELFDATA2MSB) == NULL) - INTERNAL_ERROR (fname); - } - else if (shdr_info[cnt].shdr.sh_type == SHT_GROUP) - { - /* Check whether the associated symbol table changed. */ - if (shdr_info[shdr_info[cnt].old_sh_link].newsymidx != NULL) - { - /* Yes the symbol table changed. Update the section - header of the section group. */ - scn = elf_getscn (newelf, shdr_info[cnt].idx); - GElf_Shdr shdr_mem; - GElf_Shdr *shdr = gelf_getshdr (scn, &shdr_mem); - assert (shdr != NULL); - - size_t stabidx = shdr_info[cnt].old_sh_link; - shdr->sh_info = shdr_info[stabidx].newsymidx[shdr->sh_info]; - - (void) gelf_update_shdr (scn, shdr); - } - } - } - } - - /* Finally finish the ELF header. Fill in the fields not handled by - libelf from the old file. */ - newehdr = gelf_getehdr (newelf, &newehdr_mem); - if (newehdr == NULL) - INTERNAL_ERROR (fname); - - memcpy (newehdr->e_ident, ehdr->e_ident, EI_NIDENT); - newehdr->e_type = ehdr->e_type; - newehdr->e_machine = ehdr->e_machine; - newehdr->e_version = ehdr->e_version; - newehdr->e_entry = ehdr->e_entry; - newehdr->e_flags = ehdr->e_flags; - newehdr->e_phoff = ehdr->e_phoff; - /* We need to position the section header table. */ - const size_t offsize = gelf_fsize (elf, ELF_T_OFF, 1, EV_CURRENT); - newehdr->e_shoff = ((shdr_info[shdridx].shdr.sh_offset - + shdr_info[shdridx].shdr.sh_size + offsize - 1) - & ~((GElf_Off) (offsize - 1))); - newehdr->e_shentsize = gelf_fsize (elf, ELF_T_SHDR, 1, EV_CURRENT); - - /* The new section header string table index. */ - if (likely (idx < SHN_HIRESERVE) && likely (idx != SHN_XINDEX)) - newehdr->e_shstrndx = idx; - else - { - /* The index does not fit in the ELF header field. */ - shdr_info[0].scn = elf_getscn (elf, 0); - - if (gelf_getshdr (shdr_info[0].scn, &shdr_info[0].shdr) == NULL) - INTERNAL_ERROR (fname); - - shdr_info[0].shdr.sh_link = idx; - (void) gelf_update_shdr (shdr_info[0].scn, &shdr_info[0].shdr); - - newehdr->e_shstrndx = SHN_XINDEX; - } - - if (gelf_update_ehdr (newelf, newehdr) == 0) - { - error (0, 0, gettext ("%s: error while creating ELF header: %s"), - fname, elf_errmsg (-1)); - return 1; - } - - /* We have everything from the old file. */ - if (elf_cntl (elf, ELF_C_FDDONE) != 0) - { - error (0, 0, gettext ("%s: error while reading the file: %s"), - fname, elf_errmsg (-1)); - return 1; - } - - /* The ELF library better follows our layout when this is not a - relocatable object file. */ - elf_flagelf (newelf, ELF_C_SET, - (ehdr->e_type != ET_REL ? ELF_F_LAYOUT : 0) - | (permissive ? ELF_F_PERMISSIVE : 0)); - - /* Finally write the file. */ - if (elf_update (newelf, ELF_C_WRITE) == -1) - { - error (0, 0, gettext ("while writing `%s': %s"), - fname, elf_errmsg (-1)); - result = 1; - } - - fail_close: - if (shdr_info != NULL) - { - /* For some sections we might have created an table to map symbol - table indices. */ - if (any_symtab_changes) - for (cnt = 1; cnt <= shdridx; ++cnt) - free (shdr_info[cnt].newsymidx); - - /* Free the memory. */ - if ((shnum + 2) * sizeof (struct shdr_info) > MAX_STACK_ALLOC) - free (shdr_info); - } - - /* Free other resources. */ - if (shstrtab_data != NULL) - free (shstrtab_data->d_buf); - if (shst != NULL) - ebl_strtabfree (shst); - - /* That was it. Close the descriptors. */ - if (elf_end (newelf) != 0) - { - error (0, 0, gettext ("error while finishing `%s': %s"), fname, - elf_errmsg (-1)); - result = 1; - } - - if (debugelf != NULL && elf_end (debugelf) != 0) - { - error (0, 0, gettext ("error while finishing `%s': %s"), debug_fname, - elf_errmsg (-1)); - result = 1; - } - - fail: - /* Close the EBL backend. */ - if (ebl != NULL) - ebl_closebackend (ebl); - - /* Close debug file descriptor, if opened */ - if (debug_fd >= 0) - { - if (tmp_debug_fname != NULL) - unlink (tmp_debug_fname); - close (debug_fd); - } - - /* If requested, preserve the timestamp. */ - if (tvp != NULL) - { - if (futimes (fd, tvp) != 0) - { - error (0, errno, gettext ("\ -cannot set access and modification date of \"%s\""), - output_fname ?: fname); - result = 1; - } - } - - /* Close the file descriptor if we created a new file. */ - if (output_fname != NULL) - close (fd); - - return result; -} - - -static int -handle_ar (int fd, Elf *elf, const char *prefix, const char *fname, - struct timeval tvp[2]) -{ - size_t prefix_len = prefix == NULL ? 0 : strlen (prefix); - size_t fname_len = strlen (fname) + 1; - char new_prefix[prefix_len + 1 + fname_len]; - char *cp = new_prefix; - - /* Create the full name of the file. */ - if (prefix != NULL) - { - cp = mempcpy (cp, prefix, prefix_len); - *cp++ = ':'; - } - memcpy (cp, fname, fname_len); - - - /* Process all the files contained in the archive. */ - Elf *subelf; - Elf_Cmd cmd = ELF_C_RDWR; - int result = 0; - while ((subelf = elf_begin (fd, cmd, elf)) != NULL) - { - /* The the header for this element. */ - Elf_Arhdr *arhdr = elf_getarhdr (subelf); - - if (elf_kind (subelf) == ELF_K_ELF) - result |= handle_elf (fd, subelf, new_prefix, arhdr->ar_name, 0, NULL); - else if (elf_kind (subelf) == ELF_K_AR) - result |= handle_ar (fd, subelf, new_prefix, arhdr->ar_name, NULL); - - /* Get next archive element. */ - cmd = elf_next (subelf); - if (unlikely (elf_end (subelf) != 0)) - INTERNAL_ERROR (fname); - } - - if (tvp != NULL) - { - if (unlikely (futimes (fd, tvp) != 0)) - { - error (0, errno, gettext ("\ -cannot set access and modification date of \"%s\""), fname); - result = 1; - } - } - - if (unlikely (close (fd) != 0)) - error (EXIT_FAILURE, errno, gettext ("while closing `%s'"), fname); - - return result; -} |