bootmii-autoloader/elf.c

48 lines
1.1 KiB
C

// Copyright 2008-2009 Segher Boessenkool <segher@kernel.crashing.org>
// This code is licensed to you under the terms of the GNU GPL, version 2;
// see file COPYING or http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt
#include "loader.h"
// Determine if a valid ELF image exists at the given memory location.
int valid_elf_image(void *addr)
{
u32 *header = addr;
return header[0] == 0x7f454c46 // ELF
&& header[1] == 0x01020100 // 32-bit, BE, ELF v1, SVR
&& header[4] == 0x00020014 // executable, PowerPC
&& header[5] == 1 // object file v1
&& (header[10] & 0xffff) == 32; // PHDR size
}
// Returns the entry point address.
void *load_elf_image(void *addr)
{
u32 *header = addr;
u32 *phdr = addr + header[7];
u32 n = header[11] >> 16;
u32 i;
for (i = 0; i < n; i++, phdr += 8) {
if (phdr[0] != 1) // PT_LOAD
continue;
u32 off = phdr[1];
void *dest = (void *)phdr[3];
u32 filesz = phdr[4];
u32 memsz = phdr[5];
memcpy(dest, addr + off, filesz);
memset(dest + filesz, 0, memsz - filesz);
sync_before_exec(dest, memsz);
}
return (void *)header[6];
}