From: Brian Warner Date: Fri, 20 Jul 2007 01:21:44 +0000 (-0700) Subject: upload: refactor to enable streaming upload. not all tests pass yet X-Git-Url: https://git.rkrishnan.org/%5B/%5D%20//%22%22?a=commitdiff_plain;h=9af506900b7f7c0ce96b07083e1b08cf2d8b0217;p=tahoe-lafs%2Ftahoe-lafs.git upload: refactor to enable streaming upload. not all tests pass yet --- diff --git a/src/allmydata/encode.py b/src/allmydata/encode.py index ce470c95..3290aec7 100644 --- a/src/allmydata/encode.py +++ b/src/allmydata/encode.py @@ -88,20 +88,19 @@ class Encoder(object): self.TOTAL_SHARES = n self.uri_extension_data = {} + def set_size(self, size): + self.file_size = size + def set_params(self, encoding_parameters): k,d,n = encoding_parameters self.NEEDED_SHARES = k self.SHARES_OF_HAPPINESS = d self.TOTAL_SHARES = n - def setup(self, infile, encryption_key): - self.infile = infile - assert isinstance(encryption_key, str) - assert len(encryption_key) == 16 # AES-128 - self.key = encryption_key - infile.seek(0, 2) - self.file_size = infile.tell() - infile.seek(0, 0) + def set_uploadable(self, uploadable): + self._uploadable = uploadable + + def setup(self): self.num_shares = self.TOTAL_SHARES self.required_shares = self.NEEDED_SHARES @@ -111,10 +110,13 @@ class Encoder(object): # this must be a multiple of self.required_shares self.segment_size = mathutil.next_multiple(self.segment_size, self.required_shares) - self.setup_codec() + self._setup_codec() - def setup_codec(self): + def _setup_codec(self): assert self.segment_size % self.required_shares == 0 + self.num_segments = mathutil.div_ceil(self.file_size, + self.segment_size) + self._codec = CRSEncoder() self._codec.set_params(self.segment_size, self.required_shares, self.num_shares) @@ -125,8 +127,9 @@ class Encoder(object): data['size'] = self.file_size data['segment_size'] = self.segment_size - data['num_segments'] = mathutil.div_ceil(self.file_size, - self.segment_size) + self.share_size = mathutil.div_ceil(self.file_size, + self.required_shares) + data['num_segments'] = self.num_segments data['needed_shares'] = self.required_shares data['total_shares'] = self.num_shares @@ -147,8 +150,13 @@ class Encoder(object): self.required_shares, self.num_shares) data['tail_codec_params'] = self._tail_codec.get_serialized_params() - def set_uri_extension_data(self, uri_extension_data): - self.uri_extension_data.update(uri_extension_data) + def get_serialized_params(self): + return self._codec.get_serialized_params() + + def set_encryption_key(self, key): + assert isinstance(key, str) + assert len(key) == 16 # AES-128 + self.key = key def get_share_size(self): share_size = mathutil.div_ceil(self.file_size, self.required_shares) @@ -158,6 +166,8 @@ class Encoder(object): return 0 def get_block_size(self): return self._codec.get_block_size() + def get_num_segments(self): + return self.num_segments def set_shareholders(self, landlords): assert isinstance(landlords, dict) @@ -167,14 +177,11 @@ class Encoder(object): def start(self): #paddedsize = self._size + mathutil.pad_size(self._size, self.needed_shares) - self.num_segments = mathutil.div_ceil(self.file_size, - self.segment_size) - self.share_size = mathutil.div_ceil(self.file_size, - self.required_shares) + self._plaintext_hasher = hashutil.plaintext_hasher() self._plaintext_hashes = [] + self._crypttext_hasher = hashutil.crypttext_hasher() self._crypttext_hashes = [] self.setup_encryption() - self.setup_codec() # TODO: duplicate call? d = defer.succeed(None) for l in self.landlords.values(): @@ -185,8 +192,13 @@ class Encoder(object): # captures the slot, not the value #d.addCallback(lambda res: self.do_segment(i)) # use this form instead: - d.addCallback(lambda res, i=i: self.do_segment(i)) - d.addCallback(lambda res: self.do_tail_segment(self.num_segments-1)) + d.addCallback(lambda res, i=i: self._encode_segment(i)) + d.addCallback(self._send_segment, i) + last_segnum = self.num_segments - 1 + d.addCallback(lambda res: self._encode_tail_segment(last_segnum)) + d.addCallback(self._send_segment, last_segnum) + + d.addCallback(lambda res: self.finish_flat_hashes()) d.addCallback(lambda res: self.send_plaintext_hash_tree_to_all_shareholders()) @@ -195,6 +207,7 @@ class Encoder(object): d.addCallback(lambda res: self.send_all_subshare_hash_trees()) d.addCallback(lambda res: self.send_all_share_hash_trees()) d.addCallback(lambda res: self.send_uri_extension_to_all_shareholders()) + d.addCallback(lambda res: self.close_all_shareholders()) d.addCallbacks(lambda res: self.done(), self.err) return d @@ -209,9 +222,9 @@ class Encoder(object): # that we sent to that landlord. self.share_root_hashes = [None] * self.num_shares - def do_segment(self, segnum): - chunks = [] + def _encode_segment(self, segnum): codec = self._codec + # the ICodecEncoder API wants to receive a total of self.segment_size # bytes on each encode() call, broken up into a number of # identically-sized pieces. Due to the way the codec algorithm works, @@ -228,8 +241,8 @@ class Encoder(object): # of additional shares which can be substituted if the primary ones # are unavailable - plaintext_hasher = hashutil.plaintext_segment_hasher() - crypttext_hasher = hashutil.crypttext_segment_hasher() + plaintext_segment_hasher = hashutil.plaintext_segment_hasher() + crypttext_segment_hasher = hashutil.crypttext_segment_hasher() # memory footprint: we only hold a tiny piece of the plaintext at any # given time. We build up a segment's worth of cryptttext, then hand @@ -238,56 +251,92 @@ class Encoder(object): # 10MiB. Lowering max_segment_size to, say, 100KiB would drop the # footprint to 500KiB at the expense of more hash-tree overhead. - for i in range(self.required_shares): - input_piece = self.infile.read(input_piece_size) - # non-tail segments should be the full segment size - assert len(input_piece) == input_piece_size - plaintext_hasher.update(input_piece) - encrypted_piece = self.cryptor.encrypt(input_piece) - assert len(encrypted_piece) == len(input_piece) - crypttext_hasher.update(encrypted_piece) - - chunks.append(encrypted_piece) - - self._plaintext_hashes.append(plaintext_hasher.digest()) - self._crypttext_hashes.append(crypttext_hasher.digest()) - - d = codec.encode(chunks) # during this call, we hit 5*segsize memory - del chunks - d.addCallback(self._encoded_segment, segnum) + d = self._gather_data(self.required_shares, input_piece_size, + plaintext_segment_hasher, + crypttext_segment_hasher) + def _done(chunks): + for c in chunks: + assert len(c) == input_piece_size + self._plaintext_hashes.append(plaintext_segment_hasher.digest()) + self._crypttext_hashes.append(crypttext_segment_hasher.digest()) + # during this call, we hit 5*segsize memory + return codec.encode(chunks) + d.addCallback(_done) return d - def do_tail_segment(self, segnum): - chunks = [] + def _encode_tail_segment(self, segnum): + codec = self._tail_codec input_piece_size = codec.get_block_size() - plaintext_hasher = hashutil.plaintext_segment_hasher() - crypttext_hasher = hashutil.crypttext_segment_hasher() - - for i in range(self.required_shares): - input_piece = self.infile.read(input_piece_size) - plaintext_hasher.update(input_piece) - encrypted_piece = self.cryptor.encrypt(input_piece) - assert len(encrypted_piece) == len(input_piece) - crypttext_hasher.update(encrypted_piece) - - if len(encrypted_piece) < input_piece_size: - # padding - pad_size = (input_piece_size - len(encrypted_piece)) - encrypted_piece += ('\x00' * pad_size) - - chunks.append(encrypted_piece) - - self._plaintext_hashes.append(plaintext_hasher.digest()) - self._crypttext_hashes.append(crypttext_hasher.digest()) + plaintext_segment_hasher = hashutil.plaintext_segment_hasher() + crypttext_segment_hasher = hashutil.crypttext_segment_hasher() + + d = self._gather_data(self.required_shares, input_piece_size, + plaintext_segment_hasher, + crypttext_segment_hasher, + allow_short=True) + def _done(chunks): + for c in chunks: + # a short trailing chunk will have been padded by + # _gather_data + assert len(c) == input_piece_size + self._plaintext_hashes.append(plaintext_segment_hasher.digest()) + self._crypttext_hashes.append(crypttext_segment_hasher.digest()) + return codec.encode(chunks) + d.addCallback(_done) + return d - d = codec.encode(chunks) - del chunks - d.addCallback(self._encoded_segment, segnum) + def _gather_data(self, num_chunks, input_chunk_size, + plaintext_segment_hasher, crypttext_segment_hasher, + allow_short=False, + previous_chunks=[]): + """Return a Deferred that will fire when the required number of + chunks have been read (and hashed and encrypted). The Deferred fires + with the combination of any 'previous_chunks' and the new chunks + which were gathered.""" + + if not num_chunks: + return defer.succeed(previous_chunks) + + d = self._uploadable.read(input_chunk_size) + def _got(data): + encrypted_pieces = [] + length = 0 + # we use data.pop(0) instead of 'for input_piece in data' to save + # memory: each piece is destroyed as soon as we're done with it. + while data: + input_piece = data.pop(0) + length += len(input_piece) + plaintext_segment_hasher.update(input_piece) + self._plaintext_hasher.update(input_piece) + encrypted_piece = self.cryptor.encrypt(input_piece) + assert len(encrypted_piece) == len(input_piece) + crypttext_segment_hasher.update(encrypted_piece) + self._crypttext_hasher.update(encrypted_piece) + encrypted_pieces.append(encrypted_piece) + + if allow_short: + if length < input_chunk_size: + # padding + pad_size = input_chunk_size - length + encrypted_pieces.append('\x00' * pad_size) + else: + # non-tail segments should be the full segment size + assert length == input_chunk_size + + encrypted_piece = "".join(encrypted_pieces) + return previous_chunks + [encrypted_piece] + + d.addCallback(_got) + d.addCallback(lambda chunks: + self._gather_data(num_chunks-1, input_chunk_size, + plaintext_segment_hasher, + crypttext_segment_hasher, + allow_short, chunks)) return d - def _encoded_segment(self, (shares, shareids), segnum): + def _send_segment(self, (shares, shareids), segnum): # To generate the URI, we must generate the roothash, so we must # generate all shares, even if we aren't actually giving them to # anybody. This means that the set of shares we create will be equal @@ -354,6 +403,12 @@ class Encoder(object): d0.addErrback(_eatNotEnoughPeersError) return d + def finish_flat_hashes(self): + plaintext_hash = self._plaintext_hasher.digest() + crypttext_hash = self._crypttext_hasher.digest() + self.uri_extension_data["plaintext_hash"] = plaintext_hash + self.uri_extension_data["crypttext_hash"] = crypttext_hash + def send_plaintext_hash_tree_to_all_shareholders(self): log.msg("%s sending plaintext hash tree" % self) t = HashTree(self._plaintext_hashes) @@ -445,6 +500,10 @@ class Encoder(object): def send_uri_extension_to_all_shareholders(self): log.msg("%s: sending uri_extension" % self) + for k in ('crypttext_root_hash', 'crypttext_hash', + 'plaintext_root_hash', 'plaintext_hash', + ): + assert k in self.uri_extension_data uri_extension = uri.pack_extension(self.uri_extension_data) self.uri_extension_hash = hashutil.uri_extension_hash(uri_extension) dl = [] diff --git a/src/allmydata/interfaces.py b/src/allmydata/interfaces.py index 2b4f4829..1d4d2468 100644 --- a/src/allmydata/interfaces.py +++ b/src/allmydata/interfaces.py @@ -679,14 +679,54 @@ class IDownloader(Interface): when the download is finished, or errbacks if something went wrong.""" class IUploadable(Interface): - def get_filehandle(): - """Return a filehandle from which the data to be uploaded can be - read. It must implement .read, .seek, and .tell (since the latter two - are used to determine the length of the data).""" - def close_filehandle(f): - """The upload is finished. This provides the same filehandle as was - returned by get_filehandle. This is an appropriate place to close the - filehandle.""" + def get_size(): + """Return a Deferred that will fire with the length of the data to be + uploaded, in bytes. This will be called before the data is actually + used, to compute encoding parameters. + """ + + def get_encryption_key(encoding_parameters): + """Return a Deferred that fires with a 16-byte AES key. This key will + be used to encrypt the data. The key will also be hashed to derive + the StorageIndex. 'encoding_parameters' is a string which indicates + how the data will be encoded (codec name, blocksize, number of + shares): Uploadables may wish to use these parameters while computing + the encryption key. + + Uploadables which want to achieve convergence should hash their file + contents and the encoding_parameters to form the key (which of course + requires a full pass over the data). Uploadables can use the + upload.ConvergentUploadMixin class to achieve this automatically. + + Uploadables which do not care about convergence (or do not wish to + make multiple passes over the data) can simply return a + strongly-random 16 byte string. + """ + + def read(length): + """Return a Deferred that fires with a list of strings (perhaps with + only a single element) which, when concatenated together, contain the + next 'length' bytes of data. If EOF is near, this may provide fewer + than 'length' bytes. The total number of bytes provided by read() + before it signals EOF must equal the size provided by get_size(). + + If the data must be acquired through multiple internal read + operations, returning a list instead of a single string may help to + reduce string copies. + + 'length' will typically be equal to (min(get_size(),1MB)/req_shares), + so a 10kB file means length=3kB, 100kB file means length=30kB, + and >=1MB file means length=300kB. + + This method provides for a single full pass through the data. Later + use cases may desire multiple passes or access to only parts of the + data (such as a mutable file making small edits-in-place). This API + will be expanded once those use cases are better understood. + """ + + def close(): + """The upload is finished, and whatever filehandle was in use may be + closed.""" class IUploader(Interface): def upload(uploadable): diff --git a/src/allmydata/test/test_web.py b/src/allmydata/test/test_web.py index b6182949..0b5046ff 100644 --- a/src/allmydata/test/test_web.py +++ b/src/allmydata/test/test_web.py @@ -55,12 +55,15 @@ class MyUploader(service.Service): self.files = files def upload(self, uploadable): - f = uploadable.get_filehandle() - data = f.read() - uri = str(uri_counter.next()) - self.files[uri] = data - uploadable.close_filehandle(f) - return defer.succeed(uri) + d = uploadable.get_size() + d.addCallback(lambda size: uploadable.read(size)) + d.addCallback(lambda data: "".join(data)) + def _got_data(data): + uri = str(uri_counter.next()) + self.files[uri] = data + uploadable.close() + d.addCallback(_got_data) + return d class MyDirectoryNode(dirnode.MutableDirectoryNode): @@ -94,15 +97,18 @@ class MyDirectoryNode(dirnode.MutableDirectoryNode): return defer.succeed(None) def add_file(self, name, uploadable): - f = uploadable.get_filehandle() - data = f.read() - uri = str(uri_counter.next()) - self._my_files[uri] = data - self._my_nodes[uri] = MyFileNode(uri, self._my_client) - uploadable.close_filehandle(f) - - self.children[name] = uri - return defer.succeed(self._my_nodes[uri]) + d = uploadable.get_size() + d.addCallback(lambda size: uploadable.read(size)) + d.addCallback(lambda data: "".join(data)) + def _got_data(data): + uri = str(uri_counter.next()) + self._my_files[uri] = data + self._my_nodes[uri] = MyFileNode(uri, self._my_client) + self.children[name] = uri + uploadable.close() + return self._my_nodes[uri] + d.addCallback(_got_data) + return d def delete(self, name): def _try(): diff --git a/src/allmydata/upload.py b/src/allmydata/upload.py index bebb4649..af37309d 100644 --- a/src/allmydata/upload.py +++ b/src/allmydata/upload.py @@ -1,3 +1,5 @@ + +import os from zope.interface import implements from twisted.python import log from twisted.internet import defer @@ -8,7 +10,6 @@ from allmydata.util import idlib, hashutil from allmydata import encode, storage, hashtree from allmydata.uri import pack_uri, pack_lit from allmydata.interfaces import IUploadable, IUploader -from allmydata.Crypto.Cipher import AES from cStringIO import StringIO import collections, random @@ -83,94 +84,39 @@ class PeerTracker: self.buckets.update(b) return (alreadygot, set(b.keys())) -class FileUploader: - - def __init__(self, client, options={}): - self._client = client - self._options = options - - def set_params(self, encoding_parameters): - self._encoding_parameters = encoding_parameters - - needed_shares, shares_of_happiness, total_shares = encoding_parameters - self.needed_shares = needed_shares - self.shares_of_happiness = shares_of_happiness - self.total_shares = total_shares - - def set_filehandle(self, filehandle): - self._filehandle = filehandle - filehandle.seek(0, 2) - self._size = filehandle.tell() - filehandle.seek(0) - - def set_id_strings(self, crypttext_hash, plaintext_hash): - assert isinstance(crypttext_hash, str) - assert len(crypttext_hash) == 32 - self._crypttext_hash = crypttext_hash - assert isinstance(plaintext_hash, str) - assert len(plaintext_hash) == 32 - self._plaintext_hash = plaintext_hash - - def set_encryption_key(self, key): - assert isinstance(key, str) - assert len(key) == 16 # AES-128 - self._encryption_key = key - - def start(self): - """Start uploading the file. - - The source of the data to be uploaded must have been set before this - point by calling set_filehandle(). - - This method returns a Deferred that will fire with the URI (a - string).""" - - log.msg("starting upload [%s]" % (idlib.b2a(self._crypttext_hash),)) - assert self.needed_shares - - # create the encoder, so we can know how large the shares will be - share_size, block_size = self.setup_encoder() - - d = self._locate_all_shareholders(share_size, block_size) - d.addCallback(self._send_shares) - d.addCallback(self._compute_uri) - return d - - def setup_encoder(self): - self._encoder = encode.Encoder(self._options) - self._encoder.set_params(self._encoding_parameters) - self._encoder.setup(self._filehandle, self._encryption_key) - share_size = self._encoder.get_share_size() - block_size = self._encoder.get_block_size() - return share_size, block_size +class Tahoe3PeerSelector: - def _locate_all_shareholders(self, share_size, block_size): + def get_shareholders(self, client, + storage_index, share_size, block_size, + num_segments, total_shares, shares_of_happiness): """ @return: a set of PeerTracker instances that have agreed to hold some shares for us """ + + self.total_shares = total_shares + self.shares_of_happiness = shares_of_happiness + # we are responsible for locating the shareholders. self._encoder is # responsible for handling the data and sending out the shares. - peers = self._client.get_permuted_peers(self._crypttext_hash) + peers = client.get_permuted_peers(storage_index) assert peers - # TODO: eek, don't pull this from here, find a better way. gross. - num_segments = self._encoder.uri_extension_data['num_segments'] - ht = hashtree.IncompleteHashTree(self.total_shares) # this needed_hashes computation should mirror # Encoder.send_all_share_hash_trees. We use an IncompleteHashTree # (instead of a HashTree) because we don't require actual hashing # just to count the levels. + ht = hashtree.IncompleteHashTree(total_shares) num_share_hashes = len(ht.needed_hashes(0, include_leaf=True)) trackers = [ PeerTracker(peerid, permutedid, conn, share_size, block_size, num_segments, num_share_hashes, - self._crypttext_hash) + storage_index) for permutedid, peerid, conn in peers ] self.usable_peers = set(trackers) # this set shrinks over time self.used_peers = set() # while this set grows - self.unallocated_sharenums = set(range(self.total_shares)) # this one shrinks + self.unallocated_sharenums = set(range(total_shares)) # this one shrinks return self._locate_more_shareholders() @@ -181,18 +127,23 @@ class FileUploader: def _located_some_shareholders(self, res): log.msg("_located_some_shareholders") - log.msg(" still need homes for %d shares, still have %d usable peers" % (len(self.unallocated_sharenums), len(self.usable_peers))) + log.msg(" still need homes for %d shares, still have %d usable peers" + % (len(self.unallocated_sharenums), len(self.usable_peers))) if not self.unallocated_sharenums: # Finished allocating places for all shares. - log.msg("%s._locate_all_shareholders() Finished allocating places for all shares." % self) + log.msg("%s._locate_all_shareholders() " + "Finished allocating places for all shares." % self) log.msg("used_peers is %s" % (self.used_peers,)) return self.used_peers if not self.usable_peers: # Ran out of peers who have space. - log.msg("%s._locate_all_shareholders() Ran out of peers who have space." % self) - if len(self.unallocated_sharenums) < (self.total_shares - self.shares_of_happiness): + log.msg("%s._locate_all_shareholders() " + "Ran out of peers who have space." % self) + margin = self.total_shares - self.shares_of_happiness + if len(self.unallocated_sharenums) < margin: # But we allocated places for enough shares. - log.msg("%s._locate_all_shareholders() But we allocated places for enough shares.") + log.msg("%s._locate_all_shareholders() " + "But we allocated places for enough shares.") return self.used_peers raise encode.NotEnoughPeersError # we need to keep trying @@ -201,7 +152,10 @@ class FileUploader: def _create_ring_of_things(self): PEER = 1 # must sort later than SHARE, for consistency with download SHARE = 0 - ring_of_things = [] # a list of (position_in_ring, whatami, x) where whatami is SHARE if x is a sharenum or else PEER if x is a PeerTracker instance + # ring_of_things is a list of (position_in_ring, whatami, x) where + # whatami is SHARE if x is a sharenum or else PEER if x is a + # PeerTracker instance + ring_of_things = [] ring_of_things.extend([ (peer.permutedid, PEER, peer,) for peer in self.usable_peers ]) shares = [ (i * 2**160 / self.total_shares, SHARE, i) @@ -258,7 +212,11 @@ class FileUploader: # sets into sets.Set on us, even when we're using 2.4 alreadygot = set(alreadygot) allocated = set(allocated) - #log.msg("%s._got_response(%s, %s, %s): self.unallocated_sharenums: %s, unhandled: %s" % (self, (alreadygot, allocated), peer, shares_we_requested, self.unallocated_sharenums, shares_we_requested - alreadygot - allocated)) + #log.msg("%s._got_response(%s, %s, %s): " + # "self.unallocated_sharenums: %s, unhandled: %s" + # % (self, (alreadygot, allocated), peer, shares_we_requested, + # self.unallocated_sharenums, + # shares_we_requested - alreadygot - allocated)) self.unallocated_sharenums -= alreadygot self.unallocated_sharenums -= allocated @@ -266,15 +224,90 @@ class FileUploader: self.used_peers.add(peer) if shares_we_requested - alreadygot - allocated: - #log.msg("%s._got_response(%s, %s, %s): self.unallocated_sharenums: %s, unhandled: %s HE'S FULL" % (self, (alreadygot, allocated), peer, shares_we_requested, self.unallocated_sharenums, shares_we_requested - alreadygot - allocated)) # Then he didn't accept some of the shares, so he's full. + + #log.msg("%s._got_response(%s, %s, %s): " + # "self.unallocated_sharenums: %s, unhandled: %s HE'S FULL" + # % (self, + # (alreadygot, allocated), peer, shares_we_requested, + # self.unallocated_sharenums, + # shares_we_requested - alreadygot - allocated)) self.usable_peers.remove(peer) def _got_error(self, f, peer): log.msg("%s._got_error(%s, %s)" % (self, f, peer,)) self.usable_peers.remove(peer) - def _send_shares(self, used_peers): + +class CHKUploader: + peer_selector_class = Tahoe3PeerSelector + + def __init__(self, client, uploadable, options={}): + self._client = client + self._uploadable = IUploadable(uploadable) + self._options = options + + def set_params(self, encoding_parameters): + self._encoding_parameters = encoding_parameters + + needed_shares, shares_of_happiness, total_shares = encoding_parameters + self.needed_shares = needed_shares + self.shares_of_happiness = shares_of_happiness + self.total_shares = total_shares + + def start(self): + """Start uploading the file. + + This method returns a Deferred that will fire with the URI (a + string).""" + + log.msg("starting upload of %s" % self._uploadable) + + d = self._uploadable.get_size() + d.addCallback(self.setup_encoder) + d.addCallback(self._uploadable.get_encryption_key) + d.addCallback(self.setup_keys) + d.addCallback(self.locate_all_shareholders) + d.addCallback(self.set_shareholders) + d.addCallback(lambda res: self._encoder.start()) + d.addCallback(self._compute_uri) + return d + + def setup_encoder(self, size): + self._size = size + self._encoder = encode.Encoder(self._options) + self._encoder.set_size(size) + self._encoder.set_params(self._encoding_parameters) + self._encoder.set_uploadable(self._uploadable) + self._encoder.setup() + return self._encoder.get_serialized_params() + + def setup_keys(self, key): + assert isinstance(key, str) + assert len(key) == 16 # AES-128 + self._encryption_key = key + self._encoder.set_encryption_key(key) + storage_index = hashutil.storage_index_chk_hash(key) + assert isinstance(storage_index, str) + # TODO: is there any point to having the SI be longer than the key? + # There's certainly no extra entropy to be had.. + assert len(storage_index) == 32 # SHA-256 + self._storage_index = storage_index + log.msg(" upload SI is [%s]" % (idlib.b2a(storage_index,))) + + + def locate_all_shareholders(self, ignored=None): + peer_selector = self.peer_selector_class() + share_size = self._encoder.get_share_size() + block_size = self._encoder.get_block_size() + num_segments = self._encoder.get_num_segments() + gs = peer_selector.get_shareholders + d = gs(self._client, + self._storage_index, share_size, block_size, + num_segments, self.total_shares, self.shares_of_happiness) + return d + + def set_shareholders(self, used_peers): """ @param used_peers: a sequence of PeerTracker objects """ @@ -287,14 +320,8 @@ class FileUploader: assert len(buckets) == sum([len(peer.buckets) for peer in used_peers]) self._encoder.set_shareholders(buckets) - uri_extension_data = {} - uri_extension_data['crypttext_hash'] = self._crypttext_hash - uri_extension_data['plaintext_hash'] = self._plaintext_hash - self._encoder.set_uri_extension_data(uri_extension_data) - return self._encoder.start() - def _compute_uri(self, uri_extension_hash): - return pack_uri(storage_index=self._crypttext_hash, + return pack_uri(storage_index=self._storage_index, key=self._encryption_key, uri_extension_hash=uri_extension_hash, needed_shares=self.needed_shares, @@ -302,55 +329,101 @@ class FileUploader: size=self._size, ) +def read_this_many_bytes(uploadable, size, prepend_data=[]): + d = uploadable.read(size) + def _got(data): + assert isinstance(list) + bytes = sum([len(piece) for piece in data]) + assert bytes > 0 + assert bytes <= size + remaining = size - bytes + if remaining: + return read_this_many_bytes(uploadable, remaining, + prepend_data + data) + return prepend_data + data + d.addCallback(_got) + return d + class LiteralUploader: - def __init__(self, client, options={}): + def __init__(self, client, uploadable, options={}): self._client = client + self._uploadable = IUploadable(uploadable) self._options = options - def set_filehandle(self, filehandle): - self._filehandle = filehandle + def set_params(self, encoding_parameters): + pass def start(self): - self._filehandle.seek(0) - data = self._filehandle.read() - return defer.succeed(pack_lit(data)) + d = self._uploadable.get_size() + d.addCallback(lambda size: read_this_many_bytes(self._uploadable, size)) + d.addCallback(lambda data: pack_lit("".join(data))) + return d + def close(self): + pass -class FileName: - implements(IUploadable) - def __init__(self, filename): - self._filename = filename - def get_filehandle(self): - return open(self._filename, "rb") - def close_filehandle(self, f): - f.close() -class Data: - implements(IUploadable) - def __init__(self, data): - self._data = data - def get_filehandle(self): - return StringIO(self._data) - def close_filehandle(self, f): - pass +class ConvergentUploadMixin: + # to use this, the class it is mixed in to must have a seekable + # filehandle named self._filehandle -class FileHandle: + def get_encryption_key(self, encoding_parameters): + f = self._filehandle + enckey_hasher = hashutil.key_hasher() + #enckey_hasher.update(encoding_parameters) # TODO + f.seek(0) + BLOCKSIZE = 64*1024 + while True: + data = f.read(BLOCKSIZE) + if not data: + break + enckey_hasher.update(data) + enckey = enckey_hasher.digest()[:16] + f.seek(0) + return defer.succeed(enckey) + +class NonConvergentUploadMixin: + def get_encryption_key(self, encoding_parameters): + return defer.succeed(os.urandom(16)) + + +class FileHandle(ConvergentUploadMixin): implements(IUploadable) + def __init__(self, filehandle): self._filehandle = filehandle - def get_filehandle(self): - return self._filehandle - def close_filehandle(self, f): + + def get_size(self): + self._filehandle.seek(0,2) + size = self._filehandle.tell() + self._filehandle.seek(0) + return defer.succeed(size) + + def read(self, length): + return defer.succeed([self._filehandle.read(length)]) + + def close(self): # the originator of the filehandle reserves the right to close it pass +class FileName(FileHandle): + def __init__(self, filename): + FileHandle.__init__(self, open(filename, "rb")) + def close(self): + FileHandle.close(self) + self._filehandle.close() + +class Data(FileHandle): + def __init__(self, data): + FileHandle.__init__(self, StringIO(data)) + class Uploader(service.MultiService): """I am a service that allows file uploading. """ implements(IUploader) name = "uploader" - uploader_class = FileUploader + uploader_class = CHKUploader URI_LIT_SIZE_THRESHOLD = 55 DEFAULT_ENCODING_PARAMETERS = (25, 75, 100) @@ -360,65 +433,23 @@ class Uploader(service.MultiService): # 'total' is the total number of shares created by encoding. If everybody # has room then this is is how many we will upload. - def compute_id_strings(self, f): - # return a list of (plaintext_hash, encryptionkey, crypttext_hash) - plaintext_hasher = hashutil.plaintext_hasher() - enckey_hasher = hashutil.key_hasher() - f.seek(0) - BLOCKSIZE = 64*1024 - while True: - data = f.read(BLOCKSIZE) - if not data: - break - plaintext_hasher.update(data) - enckey_hasher.update(data) - plaintext_hash = plaintext_hasher.digest() - enckey = enckey_hasher.digest() - - # now make a second pass to determine the crypttext_hash. It would be - # nice to make this involve fewer passes. - crypttext_hasher = hashutil.crypttext_hasher() - key = enckey[:16] - cryptor = AES.new(key=key, mode=AES.MODE_CTR, - counterstart="\x00"*16) - f.seek(0) - while True: - data = f.read(BLOCKSIZE) - if not data: - break - crypttext_hasher.update(cryptor.encrypt(data)) - crypttext_hash = crypttext_hasher.digest() - - # and leave the file pointer at the beginning - f.seek(0) - - return plaintext_hash, key, crypttext_hash - - def upload(self, f, options={}): + def upload(self, uploadable, options={}): # this returns the URI assert self.parent assert self.running - f = IUploadable(f) - fh = f.get_filehandle() - fh.seek(0,2) - size = fh.tell() - fh.seek(0) - if size <= self.URI_LIT_SIZE_THRESHOLD: - u = LiteralUploader(self.parent, options) - u.set_filehandle(fh) - else: - u = self.uploader_class(self.parent, options) - u.set_filehandle(fh) - encoding_parameters = self.parent.get_encoding_parameters() - if not encoding_parameters: - encoding_parameters = self.DEFAULT_ENCODING_PARAMETERS - u.set_params(encoding_parameters) - plaintext_hash, key, crypttext_hash = self.compute_id_strings(fh) - u.set_encryption_key(key) - u.set_id_strings(crypttext_hash, plaintext_hash) - d = u.start() + uploadable = IUploadable(uploadable) + d = uploadable.get_size() + def _got_size(size): + uploader_class = self.uploader_class + if size <= self.URI_LIT_SIZE_THRESHOLD: + uploader_class = LiteralUploader + uploader = self.uploader_class(self.parent, uploadable, options) + uploader.set_params(self.parent.get_encoding_parameters() + or self.DEFAULT_ENCODING_PARAMETERS) + return uploader.start() + d.addCallback(_got_size) def _done(res): - f.close_filehandle(fh) + uploadable.close() return res d.addBoth(_done) return d diff --git a/src/allmydata/util/hashutil.py b/src/allmydata/util/hashutil.py index db8c937c..62042c4b 100644 --- a/src/allmydata/util/hashutil.py +++ b/src/allmydata/util/hashutil.py @@ -22,6 +22,9 @@ def tagged_pair_hash(tag, val1, val2): def tagged_hasher(tag): return SHA256.new(netstring(tag)) +def storage_index_chk_hash(data): + return tagged_hash("allmydata_CHK_storage_index_v1", data) + def block_hash(data): return tagged_hash("allmydata_encoded_subshare_v1", data) def block_hasher():