freebsd-src/lib/libelf/libelf_ehdr.c
Joseph Koshy 3eb1a62e69 MFP4: Add an implementation of the ELF(3) and GELF(3) API set.
Bump __FreeBSD_version.

Reviewed by:	jb
2006-11-11 17:16:35 +00:00

126 lines
3.5 KiB
C

/*-
* Copyright (c) 2006 Joseph Koshy
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <assert.h>
#include <gelf.h>
#include <libelf.h>
#include <stdlib.h>
#include "_libelf.h"
#define EHDR_INIT(E,SZ) do { \
Elf##SZ##_Ehdr *eh = (E); \
eh->e_ident[EI_MAG0] = ELFMAG0; \
eh->e_ident[EI_MAG1] = ELFMAG1; \
eh->e_ident[EI_MAG2] = ELFMAG2; \
eh->e_ident[EI_MAG3] = ELFMAG3; \
eh->e_ident[EI_CLASS] = ELFCLASS##SZ; \
eh->e_ident[EI_DATA] = ELFDATANONE; \
eh->e_ident[EI_VERSION] = LIBELF_PRIVATE(version); \
eh->e_machine = EM_NONE; \
eh->e_type = ELF_K_NONE; \
eh->e_version = LIBELF_PRIVATE(version); \
} while (0)
void *
_libelf_ehdr(Elf *e, int ec, int allocate)
{
size_t fsz, msz;
void *ehdr;
void (*xlator)(char *_d, char *_s, size_t _c, int _swap);
assert(ec == ELFCLASS32 || ec == ELFCLASS64);
if (e == NULL || e->e_kind != ELF_K_ELF) {
LIBELF_SET_ERROR(ARGUMENT, 0);
return (NULL);
}
if (e->e_class != ELFCLASSNONE && e->e_class != ec) {
LIBELF_SET_ERROR(CLASS, 0);
return (NULL);
}
if (e->e_version != EV_CURRENT) {
LIBELF_SET_ERROR(VERSION, 0);
return (NULL);
}
if (e->e_class == ELFCLASSNONE)
e->e_class = ec;
if (ec == ELFCLASS32)
ehdr = (void *) e->e_u.e_elf.e_ehdr.e_ehdr32;
else
ehdr = (void *) e->e_u.e_elf.e_ehdr.e_ehdr64;
if (ehdr != NULL) /* already have a translated ehdr */
return (ehdr);
fsz = gelf_fsize(e, ELF_T_EHDR, (size_t) 1, e->e_version);
assert(fsz > 0);
if (e->e_cmd != ELF_C_WRITE && e->e_rawsize < fsz) {
LIBELF_SET_ERROR(HEADER, 0);
return (NULL);
}
msz = _libelf_msize(ELF_T_EHDR, ec, EV_CURRENT);
assert(msz > 0);
if ((ehdr = calloc((size_t) 1, msz)) == NULL) {
LIBELF_SET_ERROR(RESOURCE, 0);
return (NULL);
}
if (ec == ELFCLASS32) {
e->e_u.e_elf.e_ehdr.e_ehdr32 = ehdr;
EHDR_INIT(ehdr,32);
} else {
e->e_u.e_elf.e_ehdr.e_ehdr64 = ehdr;
EHDR_INIT(ehdr,64);
}
if (allocate)
e->e_flags |= ELF_F_DIRTY;
if (e->e_cmd == ELF_C_WRITE)
return (ehdr);
xlator = _libelf_get_translator(ELF_T_EHDR, ELF_TOMEMORY, ec);
(*xlator)(ehdr, e->e_rawfile, (size_t) 1,
e->e_byteorder != LIBELF_PRIVATE(byteorder));
return (ehdr);
}