def pack(self):
"""Return a string representation of this keyring."""
items = self.recognized + self.unrecognized
# Scramble all the items, just to make sure that no broken
# implementations rely on their oreder.
getCommonPRNG().shuffle(items)
encoded = []
for tp, val in items:
encoded.append(struct.pack("!BH", tp, len(val)))
encoded.append(val)
return "".join(encoded)
def pack(self):
"""Return a string representation of this keyring."""
items = self.recognized+self.unrecognized
# Scramble all the items, just to make sure that no broken
# implementations rely on their oreder.
getCommonPRNG().shuffle(items)
encoded = []
for tp, val in items:
encoded.append(struct.pack("!BH", tp, len(val)))
encoded.append(val)
return "".join(encoded)
def getFragments(self, s, paddingPRNG=None):
"""Given a string of length self.length, whiten it, pad it,
and fragmment it. Return a list of the fragments, in order.
(Note -- after building the fragment packets, be sure to shuffle
them into a random order.)"""
if paddingPRNG is None:
paddingPRNG = getCommonPRNG()
self.getFEC()
assert len(s) == self.length
s = whiten(s)
s += paddingPRNG.getBytes(self.paddingLen)
assert len(s) == self.paddedLen
chunks = []
for i in xrange(self.nChunks):
chunks.append( s[i*self.chunkSize:(i+1)*self.chunkSize] )
del s
fragments = []
for i in xrange(self.nChunks):
blocks = []
for j in xrange(self.k):
blocks.append( chunks[i][j*self.fragCapacity:
(j+1)*self.fragCapacity] )
chunks[i] = None
for j in xrange(self.n):
fragments.append( self.fec.encode(j, blocks) )
return fragments
def getFragments(self, s, paddingPRNG=None):
"""Given a string of length self.length, whiten it, pad it,
and fragmment it. Return a list of the fragments, in order.
(Note -- after building the fragment packets, be sure to shuffle
them into a random order.)"""
if paddingPRNG is None:
paddingPRNG = getCommonPRNG()
self.getFEC()
assert len(s) == self.length
s = whiten(s)
s += paddingPRNG.getBytes(self.paddingLen)
assert len(s) == self.paddedLen
chunks = []
for i in xrange(self.nChunks):
chunks.append(s[i * self.chunkSize:(i + 1) * self.chunkSize])
del s
fragments = []
for i in xrange(self.nChunks):
blocks = []
for j in xrange(self.k):
blocks.append(chunks[i][j * self.fragCapacity:(j + 1) *
self.fragCapacity])
chunks[i] = None
for j in xrange(self.n):
fragments.append(self.fec.encode(j, blocks))
return fragments
def getBatch(self):
n = self._getBatchSize()
count = self.count()
if n == 0 or count == 0:
return []
msgProbability = n / float(count)
rng = getCommonPRNG()
return rng.shuffle([h for h in self.getAllMessages() if rng.getFloat() < msgProbability])
def pickRandom(self, count=None):
"""Returns a list of 'count' handles to messages in this filestore.
The messages are chosen randomly, and returned in a random order.
If there are fewer than 'count' messages in the filestore,
all the messages will be included."""
handles = self.getAllMessages() # handles locking
return getCommonPRNG().shuffle(handles, count)
def openNewMessage(self):
"""Returns (file, handle) tuple to create a new message. Once
you're done writing, you must call finishMessage to
commit your changes, or abortMessage to reject them."""
while 1:
f, handle = getCommonPRNG().openNewFile(self.dir, "inp_", 1,
"msg_")
return f, handle
raise AssertionError # unreached; appease pychecker
def openNewMessage(self):
"""Returns (file, handle) tuple to create a new message. Once
you're done writing, you must call finishMessage to
commit your changes, or abortMessage to reject them."""
while 1:
f, handle = getCommonPRNG().openNewFile(self.dir, "inp_", 1,
"msg_")
return f, handle
raise AssertionError # unreached; appease pychecker
def __init__(self, s=None, isJunk=0, callback=None):
if isJunk:
self.s = getCommonPRNG().getBytes(1<<15)
else:
self.s = s
self.j = isJunk
self.cb = callback
self._failed = 0
self._succeeded = 0
def __init__(self, s=None, isJunk=0, callback=None):
if isJunk:
self.s = getCommonPRNG().getBytes(1 << 15)
else:
self.s = s
self.j = isJunk
self.cb = callback
self._failed = 0
self._succeeded = 0
def pickRandom(self, count=None):
"""Returns a list of 'count' handles to messages in this filestore.
The messages are chosen randomly, and returned in a random order.
If there are fewer than 'count' messages in the filestore,
all the messages will be included."""
handles = self.getAllMessages() # handles locking
return getCommonPRNG().shuffle(handles, count)
def getBatch(self):
n = self._getBatchSize()
count = self.count()
if n == 0 or count == 0:
return []
msgProbability = n / float(count)
rng = getCommonPRNG()
return rng.shuffle([
h for h in self.getAllMessages() if rng.getFloat() < msgProbability
])
def _writeEncryptedFile(fname, password, magic, data):
"""Write 'data' into an encrypted file named 'fname', replacing it
if necessary. Encrypts the data with the password 'password',
and uses the filetype 'magic'."""
assert len(magic) == MAGIC_LEN
prng = getCommonPRNG()
length = struct.pack("!L", len(data))
paddingLen = ceilDiv(len(data), 1024)*1024 - len(data)
padding = prng.getBytes(paddingLen)
data = "".join([length,data,padding])
salt = prng.getBytes(SALT_LEN)
key = sha1(salt+password+salt)[:AES_KEY_LEN]
digest = sha1("".join([data,salt,magic]))
encrypted = ctr_crypt(data+digest, key)
contents = "".join([magic,"\x00",salt,encrypted])
writeFile(fname, armorText(contents,
"TYPE III KEYRING", [("Version","0.1")]))
def _writeEncryptedFile(fname, password, magic, data):
"""Write 'data' into an encrypted file named 'fname', replacing it
if necessary. Encrypts the data with the password 'password',
and uses the filetype 'magic'."""
assert len(magic) == MAGIC_LEN
prng = getCommonPRNG()
length = struct.pack("!L", len(data))
paddingLen = ceilDiv(len(data), 1024) * 1024 - len(data)
padding = prng.getBytes(paddingLen)
data = "".join([length, data, padding])
salt = prng.getBytes(SALT_LEN)
key = sha1(salt + password + salt)[:AES_KEY_LEN]
digest = sha1("".join([data, salt, magic]))
encrypted = ctr_crypt(data + digest, key)
contents = "".join([magic, "\x00", salt, encrypted])
writeFile(fname,
armorText(contents, "TYPE III KEYRING", [("Version", "0.1")]))
def getBatch(self):
msgProbability = self._getFraction()
rng = getCommonPRNG()
return rng.shuffle([
h for h in self.getAllMessages() if rng.getFloat() < msgProbability
])
def __init__(self):
self.contents = getCommonPRNG().getBytes(1<<15)
def __init__(self):
self.contents = getCommonPRNG().getBytes(1 << 15)
def getBatch(self):
msgProbability = self._getFraction()
rng = getCommonPRNG()
return rng.shuffle([ h for h in self.getAllMessages()
if rng.getFloat() < msgProbability ])