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/*
* Copyright (c) 1995, 1994, 1993, 1992, 1991, 1990
* Open Software Foundation, Inc.
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies and
* that both the copyright notice and this permission notice appear in
* supporting documentation, and that the name of ("OSF") or Open Software
* Foundation not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior permission.
*
* OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL OSF BE LIABLE FOR ANY
* SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* ACTION OF CONTRACT, NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE
*/
/*
* OSF Research Institute MK6.1 (unencumbered) 1/31/1995
*/
#include <alloca.h>
#include <mach/machine/vm_types.h>
#include <mach/exec/elf.h>
#include <mach/exec/exec.h>
int exec_load(exec_read_func_t *read, exec_read_exec_func_t *read_exec,
void *handle, exec_info_t *out_info)
{
vm_size_t actual;
Elf_Ehdr x;
Elf_Phdr *phdr, *ph;
vm_size_t phsize;
int i;
int result;
vm_offset_t loadbase = 0;
/* Read the ELF header. */
if ((result = (*read)(handle, 0, &x, sizeof(x), &actual)) != 0)
return result;
if (actual < sizeof(x))
return EX_NOT_EXECUTABLE;
if ((x.e_ident[EI_MAG0] != ELFMAG0) ||
(x.e_ident[EI_MAG1] != ELFMAG1) ||
(x.e_ident[EI_MAG2] != ELFMAG2) ||
(x.e_ident[EI_MAG3] != ELFMAG3))
return EX_NOT_EXECUTABLE;
/* Make sure the file is of the right architecture. */
if ((x.e_ident[EI_CLASS] != MY_ELF_CLASS) ||
(x.e_ident[EI_DATA] != MY_EI_DATA) ||
(x.e_machine != MY_E_MACHINE))
return EX_WRONG_ARCH;
/* Leave room for mmaps etc. before PIE binaries.
* Could add address randomization here. */
if (x.e_type == ET_DYN || x.e_type == ET_REL)
loadbase = 128 << 20;
/* XXX others */
out_info->entry = (vm_offset_t) x.e_entry + loadbase;
phsize = x.e_phnum * x.e_phentsize;
phdr = (Elf_Phdr *)alloca(phsize);
result = (*read)(handle, x.e_phoff, phdr, phsize, &actual);
if (result)
return result;
if (actual < phsize)
return EX_CORRUPT;
out_info->stack_prot = VM_PROT_ALL;
for (i = 0; i < x.e_phnum; i++)
{
ph = (Elf_Phdr *)((vm_offset_t)phdr + i * x.e_phentsize);
if (ph->p_type == PT_LOAD)
{
exec_sectype_t type = EXEC_SECTYPE_ALLOC |
EXEC_SECTYPE_LOAD;
if (ph->p_flags & PF_R) type |= EXEC_SECTYPE_READ;
if (ph->p_flags & PF_W) type |= EXEC_SECTYPE_WRITE;
if (ph->p_flags & PF_X) type |= EXEC_SECTYPE_EXECUTE;
result = (*read_exec)(handle,
ph->p_offset, ph->p_filesz,
ph->p_vaddr + loadbase, ph->p_memsz, type);
if (result)
return result;
} else if (ph->p_type == PT_GNU_STACK) {
out_info->stack_prot = 0;
if (ph->p_flags & PF_R) out_info->stack_prot |= VM_PROT_READ;
if (ph->p_flags & PF_W) out_info->stack_prot |= VM_PROT_WRITE;
if (ph->p_flags & PF_X) out_info->stack_prot |= VM_PROT_EXECUTE;
}
}
return 0;
}
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