def __init__(self,
nca3,
section_header,
verify=False,
ifo=0,
buffer=65536):
self.nca = nca3
self.section_header = section_header
self.key = self.nca.body_key
self.nonce = pk_u64(self.section_header.section_ctr,
endianness='>')
self.section_offset = self.section_header.offset
self.section_size = self.section_header.size
self.fs_type = self.section_header.fs_type
self.crypto = self.section_header.crypto_type
self.ifo = ifo
self.buffer = buffer
if self.crypto in ('BTKR', 'XTS'):
raise NotImplementedError('BTKR/XTS not implemented')
super(NCA3.SectionInNCA3,
self).__init__(self.nca.f, self.section_offset,
self.section_size)
self.is_exefs = False
if self.fs_type == 'PFS0':
self.cont_offset = self.section_header.superblock.offset
self.cont_size = self.section_header.superblock.size
self.fs = HashTableWrappedPFS0(self.section_header.superblock,
self,
verify=verify)
if 'main.npdm' in self.fs.files:
self.is_exefs = True
elif self.fs_type == 'RomFS':
self.cont_offset = self.section_header.superblock.lvls[
IVFCSuperblock.IVFC_MAX_LEVEL - 1].offset
self.cont_size = self.section_header.superblock.lvls[
IVFCSuperblock.IVFC_MAX_LEVEL - 1].size
self.fs = HashTreeWrappedRomFS(self.section_header.superblock,
self,
verify=verify)
class SectionInNCA3(FileInContainer):
def __init__(self,
nca3,
section_header,
verify=False,
ifo=0,
buffer=65536):
self.nca = nca3
self.section_header = section_header
self.key = self.nca.body_key
self.nonce = pk_u64(self.section_header.section_ctr,
endianness='>')
self.section_offset = self.section_header.offset
self.section_size = self.section_header.size
self.fs_type = self.section_header.fs_type
self.crypto = self.section_header.crypto_type
self.ifo = ifo
self.buffer = buffer
if self.crypto in ('BTKR', 'XTS'):
raise NotImplementedError('BTKR/XTS not implemented')
super(NCA3.SectionInNCA3,
self).__init__(self.nca.f, self.section_offset,
self.section_size)
self.is_exefs = False
if self.fs_type == 'PFS0':
self.cont_offset = self.section_header.superblock.offset
self.cont_size = self.section_header.superblock.size
self.fs = HashTableWrappedPFS0(self.section_header.superblock,
self,
verify=verify)
if 'main.npdm' in self.fs.files:
self.is_exefs = True
elif self.fs_type == 'RomFS':
self.cont_offset = self.section_header.superblock.lvls[
IVFCSuperblock.IVFC_MAX_LEVEL - 1].offset
self.cont_size = self.section_header.superblock.lvls[
IVFCSuperblock.IVFC_MAX_LEVEL - 1].size
self.fs = HashTreeWrappedRomFS(self.section_header.superblock,
self,
verify=verify)
def update_ctr(self, off):
self.ctr = Counter.new(
64,
prefix=self.nonce,
initial_value=((self.section_offset + off) >> 4))
self.cipher = AES.new(self.key, AES.MODE_CTR, counter=self.ctr)
def seek(self, off):
if self.crypto == 'None' or self.crypto == 'BTKR' or self.crypto == 'XTS':
super(NCA3.SectionInNCA3, self).seek(self.ifo + off)
elif self.crypto == 'CTR':
block_offset = off & ~0xF
self.sector_offset = off & 0xF
super(NCA3.SectionInNCA3, self).seek(self.ifo + block_offset)
self.update_ctr(block_offset)
def read(self, length=None):
if self.crypto == 'None' or self.crypto == 'BTKR' or self.crypto == 'XTS':
data = super(NCA3.SectionInNCA3, self).read(length)
return data
elif self.crypto == 'CTR':
aligned_length = align_to(length + self.sector_offset, 0x10)
dec_data = self.cipher.decrypt(
super(NCA3.SectionInNCA3, self).read(aligned_length))
if aligned_length != length:
try:
return dec_data[self.sector_offset:length +
self.sector_offset]
finally: # Seek to what the offset should be if not for the crypto
self.seek(self.ifo + self.tell() - aligned_length +
length)
else:
return dec_data[:length]
def _decrypt_from_offset(self, off, size=None):
self.seek(off + self.ifo)
read = 0
while True:
buf = self.read(self.buffer)
if not buf:
break
if size and (read + len(buf) >= size):
yield buf[:size - read]
break
yield buf
read += len(buf)
def decrypt_raw(self):
for buf in self._decrypt_from_offset(0):
yield buf
def decrypt_raw_cont(self):
for buf in self._decrypt_from_offset(self.cont_offset,
self.cont_size):
yield buf
def extract_cont(self, dest=None):
self.fs.extract(dest, disp=False)