def test_concat(self):
"Test that we can concatenate output and retrieve the objects back out."
self._oso(self.test_objects)
fob = StringIO()
for ob in self.test_objects:
dump(ob, fob)
fob.seek(0)
obs2 = []
try:
while True:
obs2.append(load(fob))
except EOFError:
pass
assert obs2 == self.test_objects
def recvfrom(self, bufsize, flags=0):
if self.type != socket.SOCK_DGRAM:
return _BaseSocket.recvfrom(self, bufsize, flags)
if not self._proxyconn:
self.bind(("", 0))
buf = BytesIO(_BaseSocket.recv(self, bufsize + 1024, flags))
buf.seek(2, 1)
frag = buf.read(1)
if ord(frag):
raise NotImplementedError("Received UDP packet fragment")
fromhost, fromport = self._read_SOCKS5_address(buf)
if self.proxy_peername:
peerhost, peerport = self.proxy_peername
if fromhost != peerhost or peerport not in (0, fromport):
raise socket.error(EAGAIN, "Packet filtered")
return (buf.read(bufsize), (fromhost, fromport))
def load(self, dis=None):
# Search all slots for any we can read, decrypt that,
# and pick the newest one (in unlikely case of dups)
# reset
self.current.clear()
self.overrides.clear()
self.my_pos = 0
self.is_dirty = 0
self.capacity = 0
# 4k, but last 32 bytes are a SHA (itself encrypted)
global _tmp
buf = bytearray(4)
empty = 0
for pos in SLOTS:
if dis:
dis.progress_bar_show(
(pos - SLOTS.start) / (SLOTS.stop - SLOTS.start))
gc.collect()
SF.read(pos, buf)
if buf[0] == buf[1] == buf[2] == buf[3] == 0xff:
# erased (probably)
empty += 1
continue
# check if first 2 bytes makes sense for JSON
aes = self.get_aes(pos)
chk = aes.copy().cipher(b'{"')
if chk != buf[0:2]:
# doesn't look like JSON meant for me
continue
# probably good, read it
chk = sha256()
aes = aes.cipher
expect = None
with SFFile(pos, length=4096, pre_erased=True) as fd:
for i in range(4096 / 32):
b = aes(fd.read(32))
if i != 127:
_tmp[i * 32:(i * 32) + 32] = b
chk.update(b)
else:
expect = b
try:
# verify checksum in last 32 bytes
assert expect == chk.digest()
# loads() can't work from a byte array, and converting to
# bytes here would copy it; better to use file emulation.
fd = BytesIO(_tmp)
d = ujson.load(fd)
self.capacity = fd.seek(0, 1) / 4096 # .tell() is missing
except:
# One in 65k or so chance to come here w/ garbage decoded, so
# not an error.
continue
got_age = d.get('_age', 0)
if got_age > self.current.get('_age', -1):
# likely winner
self.current = d
self.my_pos = pos
#print("NV: data @ %d w/ age=%d" % (pos, got_age))
else:
# stale data seen; clean it up.
assert self.current['_age'] > 0
#print("NV: cleanup @ %d" % pos)
SF.sector_erase(pos)
SF.wait_done()
# 4k is a large object, sigh, for us right now. cleanup
gc.collect()
# done, if we found something
if self.my_pos:
return
# nothing found.
self.my_pos = 0
self.current = self.default_values()
if empty == len(SLOTS):
# Whole thing is blank. Bad for plausible deniability. Write 3 slots
# with garbage. They will be wasted space until it fills.
blks = list(SLOTS)
shuffle(blks)
for pos in blks[0:3]:
for i in range(0, 4096, 256):
h = ngu.random.bytes(256)
SF.wait_done()
SF.write(pos + i, h)