def add_function(self, function):
import peachpy.x86_64.function
assert isinstance(function, peachpy.x86_64.function.ABIFunction), \
"Function must be finalized with an ABI before its assembly can be used"
from peachpy.formats.macho.symbol import Symbol, SymbolType, SymbolDescription, SymbolVisibility, \
Relocation, RelocationType
from peachpy.util import roundup
encoded_function = function.encode()
code_offset = len(self.image.text_section.content)
code_padding = bytearray([encoded_function.code_section.alignment_byte] *
(roundup(code_offset, encoded_function.code_section.alignment) - code_offset))
self.image.text_section.content += code_padding
code_offset += len(code_padding)
self.image.text_section.content += encoded_function.code_section.content
self.image.text_section.alignment = \
max(self.image.text_section.alignment, encoded_function.code_section.alignment)
const_offset = self.image.const_section.content_size
const_padding = bytearray([encoded_function.const_section.alignment_byte] *
(roundup(const_offset, encoded_function.const_section.alignment) - const_offset))
self.image.const_section.content += const_padding
const_offset += len(const_padding)
self.image.const_section.content += encoded_function.const_section.content
self.image.const_section.alignment = \
max(self.image.const_section.alignment, encoded_function.const_section.alignment)
# Map from PeachPy symbol to Mach-O symbol
symbol_map = dict()
for symbol in encoded_function.const_section.symbols:
macho_symbol = Symbol("_" + function.mangled_name + "." + symbol.name,
SymbolType.section_relative, self.image.const_section,
const_offset + symbol.offset)
macho_symbol.description = SymbolDescription.defined
self.image.symbol_table.add_symbol(macho_symbol)
symbol_map[symbol] = macho_symbol
for relocation in encoded_function.code_section.relocations:
macho_relocation = Relocation(RelocationType.x86_64_signed, code_offset + relocation.offset, 4,
symbol_map[relocation.symbol], is_pc_relative=True)
relocation_addend = relocation.offset + 4 - relocation.program_counter
if relocation_addend != 0:
self.image.text_section.content[code_offset + relocation.offset] = relocation_addend & 0xFF
self.image.text_section.content[code_offset + relocation.offset + 1] = (relocation_addend >> 8) & 0xFF
self.image.text_section.content[code_offset + relocation.offset + 2] = (relocation_addend >> 16) & 0xFF
self.image.text_section.content[code_offset + relocation.offset + 3] = (relocation_addend >> 24) & 0xFF
self.image.text_section.relocations.append(macho_relocation)
function_symbol = Symbol("_" + function.mangled_name, SymbolType.section_relative, self.image.text_section,
value=code_offset)
function_symbol.description = SymbolDescription.defined
function_symbol.visibility = SymbolVisibility.external
self.image.symbol_table.add_symbol(function_symbol)
def add_function(self, function):
import peachpy.x86_64.function
assert isinstance(function, peachpy.x86_64.function.ABIFunction), \
"Function must be bindinded to an ABI before its assembly can be used"
from peachpy.util import roundup
from peachpy.formats.mscoff import Symbol, SymbolType, StorageClass, Relocation, RelocationType
encoded_function = function.encode()
code_offset = len(self.text_section.content)
code_padding = bytearray([encoded_function.code_section.alignment_byte] *
(roundup(code_offset, encoded_function.code_section.alignment) - code_offset))
code_offset += len(code_padding)
self.text_section.content += encoded_function.code_section.content
self.text_section.alignment = \
max(self.text_section.alignment, encoded_function.code_section.alignment)
rdata_offset = self.rdata_section.content_size
rdata_padding = bytearray([encoded_function.const_section.alignment_byte] *
(roundup(rdata_offset, encoded_function.const_section.alignment) - rdata_offset))
self.rdata_section.content += rdata_padding
rdata_offset += len(rdata_padding)
self.rdata_section.content += encoded_function.const_section.content
self.rdata_section.alignment = \
max(self.rdata_section.alignment, encoded_function.const_section.alignment)
# Map from PeachPy symbol to Mach-O symbol
symbol_map = dict()
for symbol in encoded_function.const_section.symbols:
mscoff_symbol = Symbol()
mscoff_symbol.name = symbol.name
mscoff_symbol.value = rdata_offset + symbol.offset
mscoff_symbol.section = self.rdata_section
mscoff_symbol.symbol_type = SymbolType.non_function
mscoff_symbol.storage_class = StorageClass.static
self.image.add_symbol(mscoff_symbol)
symbol_map[symbol] = mscoff_symbol
for relocation in encoded_function.code_section.relocations:
mscoff_relocation = Relocation(RelocationType.x86_64_relocation_offset32,
code_offset + relocation.offset,
symbol_map[relocation.symbol])
self.text_section.relocations.append(mscoff_relocation)
function_symbol = Symbol()
function_symbol.name = function.name
function_symbol.value = code_offset
function_symbol.section = self.text_section
function_symbol.symbol_type = SymbolType.function
function_symbol.storage_class = StorageClass.external
self.image.add_symbol(function_symbol)