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#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libmcpu.h>
#include <mcpu-elf.h>
#include "mcpu-melf.h"
typedef struct fixture_shdr
{
__mpu_uint32_t name;
__mpu_uint32_t type;
__mpu_uint64_t flags;
__mpu_uint64_t addr;
__mpu_uint64_t offset;
__mpu_uint64_t size;
__mpu_uint32_t link;
__mpu_uint32_t info;
__mpu_uint64_t align;
__mpu_uint64_t entsize;
} fixture_shdr;
static void
get_shdr( const unsigned char *p, int data, fixture_shdr *sh )
{
memset( sh, 0, sizeof( *sh ) );
sh->name = cpu_melf_get32( p + MELF64_SHDR_SH_NAME_OFF, data );
sh->type = cpu_melf_get32( p + MELF64_SHDR_SH_TYPE_OFF, data );
sh->flags = cpu_melf_get64( p + MELF64_SHDR_SH_FLAGS_OFF, data );
sh->addr = cpu_melf_get64( p + MELF64_SHDR_SH_ADDR_OFF, data );
sh->offset = cpu_melf_get64( p + MELF64_SHDR_SH_OFFSET_OFF, data );
sh->size = cpu_melf_get64( p + MELF64_SHDR_SH_SIZE_OFF, data );
sh->link = cpu_melf_get32( p + MELF64_SHDR_SH_LINK_OFF, data );
sh->info = cpu_melf_get32( p + MELF64_SHDR_SH_INFO_OFF, data );
sh->align = cpu_melf_get64( p + MELF64_SHDR_SH_ADDRALIGN_OFF, data );
sh->entsize = cpu_melf_get64( p + MELF64_SHDR_SH_ENTSIZE_OFF, data );
} /* End of get_shdr() */
static void
put_shdr( unsigned char *p, int data, const fixture_shdr *sh )
{
memset( p, 0, MELF64_SHDR_SIZE );
cpu_melf_put32( p + MELF64_SHDR_SH_NAME_OFF, sh->name, data );
cpu_melf_put32( p + MELF64_SHDR_SH_TYPE_OFF, sh->type, data );
cpu_melf_put64( p + MELF64_SHDR_SH_FLAGS_OFF, sh->flags, data );
cpu_melf_put64( p + MELF64_SHDR_SH_ADDR_OFF, sh->addr, data );
cpu_melf_put64( p + MELF64_SHDR_SH_OFFSET_OFF, sh->offset, data );
cpu_melf_put64( p + MELF64_SHDR_SH_SIZE_OFF, sh->size, data );
cpu_melf_put32( p + MELF64_SHDR_SH_LINK_OFF, sh->link, data );
cpu_melf_put32( p + MELF64_SHDR_SH_INFO_OFF, sh->info, data );
cpu_melf_put64( p + MELF64_SHDR_SH_ADDRALIGN_OFF, sh->align, data );
cpu_melf_put64( p + MELF64_SHDR_SH_ENTSIZE_OFF, sh->entsize, data );
} /* End of put_shdr() */
static const char *
name_at( const unsigned char *table, size_t size, __mpu_uint32_t offset )
{
const unsigned char *p;
if( offset >= size )
return( NULL );
p = table + offset;
if( !memchr( p, 0, size - offset ) )
return( NULL );
return( (const char *)p );
} /* End of name_at() */
int
main( int argc, char **argv )
{
unsigned char *file = NULL;
unsigned char *out = NULL;
fixture_shdr *sh = NULL;
const unsigned char *old_shstr;
size_t file_size = 0;
size_t old_shstr_size;
size_t new_shstr_size;
size_t i;
size_t text_index = 0;
int data;
int overflow = 0;
__mpu_uint64_t old_shoff;
__mpu_uint64_t cur;
__mpu_uint64_t new_shoff;
__mpu_uint64_t total;
__mpu_uint16_t shnum;
__mpu_uint16_t shentsize;
__mpu_uint16_t shstrndx;
fixture_shdr strtab;
fixture_shdr symtab;
fixture_shdr shstr;
unsigned char symbols[2 * MELF64_SYM_SIZE];
const char fixture_strtab[] = "\0fixture_symbol\0";
const char strtab_name[] = ".strtab";
const char symtab_name[] = ".symtab";
char err[256];
int rc = EXIT_FAILURE;
if( argc != 3 )
{
fprintf( stderr, "usage: %s INPUT-ET_EXEC-OR-ET_DYN OUTPUT\n", argv[0] );
return( EXIT_FAILURE );
}
if( cpu_melf_readall( argv[1], &file, &file_size, err, sizeof( err ) ) )
{
fprintf( stderr, "%s\n", err );
return( EXIT_FAILURE );
}
if( file_size < MELF64_EHDR_SIZE ||
file[MELF_EI_MAG0] != MELFMAG0 || file[MELF_EI_MAG1] != MELFMAG1 ||
file[MELF_EI_MAG2] != MELFMAG2 || file[MELF_EI_MAG3] != MELFMAG3 ||
file[MELF_EI_CLASS] != MELF_CLASS_64 )
goto out;
data = file[MELF_EI_DATA];
if( data != MELF_DATA_LSB && data != MELF_DATA_MSB )
goto out;
{
__mpu_uint16_t type = cpu_melf_get16(
file + MELF64_EHDR_E_TYPE_OFF, data );
if( type != MELF_ET_EXEC && type != MELF_ET_DYN )
goto out;
}
old_shoff = cpu_melf_get64( file + MELF64_EHDR_E_SHOFF_OFF, data );
shnum = cpu_melf_get16( file + MELF64_EHDR_E_SHNUM_OFF, data );
shentsize = cpu_melf_get16( file + MELF64_EHDR_E_SHENTSIZE_OFF, data );
shstrndx = cpu_melf_get16( file + MELF64_EHDR_E_SHSTRNDX_OFF, data );
if( !shnum || shnum > UINT16_MAX - 2 || shentsize != MELF64_SHDR_SIZE ||
shstrndx >= shnum ||
!cpu_melf_span( file_size, old_shoff,
(__mpu_uint64_t)shnum * MELF64_SHDR_SIZE ) )
goto out;
sh = (fixture_shdr *)calloc( (size_t)shnum + 2, sizeof( *sh ) );
if( !sh )
goto out;
for( i = 0; i < shnum; ++i )
get_shdr( file + (size_t)old_shoff + i * MELF64_SHDR_SIZE,
data, &sh[i] );
if( sh[shstrndx].type != MELF_SHT_STRTAB ||
!cpu_melf_span( file_size, sh[shstrndx].offset,
sh[shstrndx].size ) ||
sh[shstrndx].size > SIZE_MAX )
goto out;
old_shstr = file + (size_t)sh[shstrndx].offset;
old_shstr_size = (size_t)sh[shstrndx].size;
for( i = 1; i < shnum; ++i )
{
const char *name = name_at( old_shstr, old_shstr_size, sh[i].name );
if( !name )
goto out;
if( !strcmp( name, MELF_SEC_TEXT ) )
text_index = i;
}
if( !text_index )
goto out;
cur = old_shoff;
memset( &strtab, 0, sizeof( strtab ) );
strtab.type = MELF_SHT_STRTAB;
strtab.offset = cur;
strtab.size = sizeof( fixture_strtab );
strtab.align = 1;
cur += strtab.size;
cur = cpu_melf_align_up( cur, 8, &overflow );
if( overflow )
goto out;
memset( &symtab, 0, sizeof( symtab ) );
symtab.type = MELF_SHT_SYMTAB;
symtab.offset = cur;
symtab.size = sizeof( symbols );
symtab.link = shnum;
symtab.info = 1;
symtab.align = 8;
symtab.entsize = MELF64_SYM_SIZE;
cur += symtab.size;
if( old_shstr_size > SIZE_MAX - sizeof( strtab_name ) ||
old_shstr_size + sizeof( strtab_name ) > SIZE_MAX - sizeof( symtab_name ) )
goto out;
new_shstr_size = old_shstr_size + sizeof( strtab_name ) +
sizeof( symtab_name );
shstr = sh[shstrndx];
shstr.offset = cur;
shstr.size = new_shstr_size;
cur += new_shstr_size;
new_shoff = cpu_melf_align_up( cur, 8, &overflow );
if( overflow || new_shoff > UINT64_MAX -
(__mpu_uint64_t)( shnum + 2 ) * MELF64_SHDR_SIZE )
goto out;
total = new_shoff + (__mpu_uint64_t)( shnum + 2 ) * MELF64_SHDR_SIZE;
if( total > SIZE_MAX )
goto out;
out = (unsigned char *)calloc( (size_t)total, 1 );
if( !out )
goto out;
memcpy( out, file, (size_t)old_shoff );
memcpy( out + (size_t)strtab.offset, fixture_strtab,
sizeof( fixture_strtab ) );
memset( symbols, 0, sizeof( symbols ) );
cpu_melf_put32( symbols + MELF64_SYM_SIZE + MELF64_SYM_ST_NAME_OFF,
1, data );
symbols[MELF64_SYM_SIZE + MELF64_SYM_ST_INFO_OFF] =
MELF64_ST_INFO( MELF_STB_GLOBAL, MELF_STT_FUNC );
symbols[MELF64_SYM_SIZE + MELF64_SYM_ST_OTHER_OFF] = MELF_STV_DEFAULT;
cpu_melf_put16( symbols + MELF64_SYM_SIZE + MELF64_SYM_ST_SHNDX_OFF,
(__mpu_uint16_t)text_index, data );
cpu_melf_put64( symbols + MELF64_SYM_SIZE + MELF64_SYM_ST_VALUE_OFF,
sh[text_index].addr, data );
memcpy( out + (size_t)symtab.offset, symbols, sizeof( symbols ) );
memcpy( out + (size_t)shstr.offset, old_shstr, old_shstr_size );
memcpy( out + (size_t)shstr.offset + old_shstr_size,
strtab_name, sizeof( strtab_name ) );
memcpy( out + (size_t)shstr.offset + old_shstr_size + sizeof( strtab_name ),
symtab_name, sizeof( symtab_name ) );
strtab.name = (__mpu_uint32_t)old_shstr_size;
symtab.name = (__mpu_uint32_t)( old_shstr_size + sizeof( strtab_name ) );
sh[shstrndx] = shstr;
sh[shnum] = strtab;
sh[shnum + 1] = symtab;
for( i = 0; i < (size_t)shnum + 2; ++i )
put_shdr( out + (size_t)new_shoff + i * MELF64_SHDR_SIZE,
data, &sh[i] );
cpu_melf_put64( out + MELF64_EHDR_E_SHOFF_OFF, new_shoff, data );
cpu_melf_put16( out + MELF64_EHDR_E_SHNUM_OFF,
(__mpu_uint16_t)( shnum + 2 ), data );
if( cpu_melf_writeall( argv[2], out, (size_t)total, err, sizeof( err ) ) )
{
fprintf( stderr, "%s\n", err );
goto out;
}
rc = EXIT_SUCCESS;
out:
free( out );
free( sh );
free( file );
return( rc );
} /* End of main() */
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