From: Brian Warner Date: Thu, 17 Apr 2008 20:09:22 +0000 (-0700) Subject: mutable WIP: merge in patches from current trunk X-Git-Tag: allmydata-tahoe-1.1.0~232 X-Git-Url: https://git.rkrishnan.org/architecture.txt?a=commitdiff_plain;h=157073d8d8f0958333e11a1fb8133003c4ca01d7;p=tahoe-lafs%2Ftahoe-lafs.git mutable WIP: merge in patches from current trunk --- diff --git a/src/allmydata/mutable.py b/src/allmydata/mutable.py deleted file mode 100644 index 29b10769..00000000 --- a/src/allmydata/mutable.py +++ /dev/null @@ -1,2470 +0,0 @@ - -import os, sys, struct, time, weakref -from itertools import count -from zope.interface import implements -from twisted.internet import defer -from twisted.python import failure -from twisted.application import service -from foolscap.eventual import eventually -from allmydata.interfaces import IMutableFileNode, IMutableFileURI, \ - IPublishStatus, IRetrieveStatus -from allmydata.util import base32, hashutil, mathutil, idlib, log -from allmydata.uri import WriteableSSKFileURI -from allmydata import hashtree, codec, storage -from allmydata.encode import NotEnoughPeersError -from pycryptopp.publickey import rsa -from pycryptopp.cipher.aes import AES - - -class NotMutableError(Exception): - pass - -class NeedMoreDataError(Exception): - def __init__(self, needed_bytes, encprivkey_offset, encprivkey_length): - Exception.__init__(self) - self.needed_bytes = needed_bytes # up through EOF - self.encprivkey_offset = encprivkey_offset - self.encprivkey_length = encprivkey_length - def __str__(self): - return "" % self.needed_bytes - -class UncoordinatedWriteError(Exception): - def __repr__(self): - return "<%s -- You, oh user, tried to change a file or directory at the same time as another process was trying to change it. To avoid data loss, don't do this. Please see docs/write_coordination.html for details.>" % (self.__class__.__name__,) - -class UnrecoverableFileError(Exception): - pass - -class CorruptShareError(Exception): - def __init__(self, peerid, shnum, reason): - self.args = (peerid, shnum, reason) - self.peerid = peerid - self.shnum = shnum - self.reason = reason - def __str__(self): - short_peerid = idlib.nodeid_b2a(self.peerid)[:8] - return "= HEADER_LENGTH, len(data) - prefix = data[:struct.calcsize(SIGNED_PREFIX)] - - (version, - seqnum, - root_hash, - IV, - k, N, segsize, datalen, - o) = unpack_header(data) - - assert version == 0 - if len(data) < o['share_hash_chain']: - raise NeedMoreDataError(o['share_hash_chain'], - o['enc_privkey'], o['EOF']-o['enc_privkey']) - - pubkey_s = data[HEADER_LENGTH:o['signature']] - signature = data[o['signature']:o['share_hash_chain']] - - return (seqnum, root_hash, IV, k, N, segsize, datalen, - pubkey_s, signature, prefix) - -def unpack_share(data): - assert len(data) >= HEADER_LENGTH - o = {} - (version, - seqnum, - root_hash, - IV, - k, N, segsize, datalen, - o['signature'], - o['share_hash_chain'], - o['block_hash_tree'], - o['share_data'], - o['enc_privkey'], - o['EOF']) = struct.unpack(HEADER, data[:HEADER_LENGTH]) - - assert version == 0 - if len(data) < o['EOF']: - raise NeedMoreDataError(o['EOF'], - o['enc_privkey'], o['EOF']-o['enc_privkey']) - - pubkey = data[HEADER_LENGTH:o['signature']] - signature = data[o['signature']:o['share_hash_chain']] - share_hash_chain_s = data[o['share_hash_chain']:o['block_hash_tree']] - share_hash_format = ">H32s" - hsize = struct.calcsize(share_hash_format) - assert len(share_hash_chain_s) % hsize == 0, len(share_hash_chain_s) - share_hash_chain = [] - for i in range(0, len(share_hash_chain_s), hsize): - chunk = share_hash_chain_s[i:i+hsize] - (hid, h) = struct.unpack(share_hash_format, chunk) - share_hash_chain.append( (hid, h) ) - share_hash_chain = dict(share_hash_chain) - block_hash_tree_s = data[o['block_hash_tree']:o['share_data']] - assert len(block_hash_tree_s) % 32 == 0, len(block_hash_tree_s) - block_hash_tree = [] - for i in range(0, len(block_hash_tree_s), 32): - block_hash_tree.append(block_hash_tree_s[i:i+32]) - - share_data = data[o['share_data']:o['enc_privkey']] - enc_privkey = data[o['enc_privkey']:o['EOF']] - - return (seqnum, root_hash, IV, k, N, segsize, datalen, - pubkey, signature, share_hash_chain, block_hash_tree, - share_data, enc_privkey) - -def unpack_share_data(verinfo, hash_and_data): - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, o_t) = verinfo - - # hash_and_data starts with the share_hash_chain, so figure out what the - # offsets really are - o = dict(o_t) - o_share_hash_chain = 0 - o_block_hash_tree = o['block_hash_tree'] - o['share_hash_chain'] - o_share_data = o['share_data'] - o['share_hash_chain'] - o_enc_privkey = o['enc_privkey'] - o['share_hash_chain'] - - share_hash_chain_s = hash_and_data[o_share_hash_chain:o_block_hash_tree] - share_hash_format = ">H32s" - hsize = struct.calcsize(share_hash_format) - assert len(share_hash_chain_s) % hsize == 0, len(share_hash_chain_s) - share_hash_chain = [] - for i in range(0, len(share_hash_chain_s), hsize): - chunk = share_hash_chain_s[i:i+hsize] - (hid, h) = struct.unpack(share_hash_format, chunk) - share_hash_chain.append( (hid, h) ) - share_hash_chain = dict(share_hash_chain) - block_hash_tree_s = hash_and_data[o_block_hash_tree:o_share_data] - assert len(block_hash_tree_s) % 32 == 0, len(block_hash_tree_s) - block_hash_tree = [] - for i in range(0, len(block_hash_tree_s), 32): - block_hash_tree.append(block_hash_tree_s[i:i+32]) - - share_data = hash_and_data[o_share_data:o_enc_privkey] - - return (share_hash_chain, block_hash_tree, share_data) - - -def pack_checkstring(seqnum, root_hash, IV): - return struct.pack(PREFIX, - 0, # version, - seqnum, - root_hash, - IV) - -def unpack_checkstring(checkstring): - cs_len = struct.calcsize(PREFIX) - version, seqnum, root_hash, IV = struct.unpack(PREFIX, checkstring[:cs_len]) - assert version == 0 # TODO: just ignore the share - return (seqnum, root_hash, IV) - -def pack_prefix(seqnum, root_hash, IV, - required_shares, total_shares, - segment_size, data_length): - prefix = struct.pack(SIGNED_PREFIX, - 0, # version, - seqnum, - root_hash, - IV, - - required_shares, - total_shares, - segment_size, - data_length, - ) - return prefix - -def pack_offsets(verification_key_length, signature_length, - share_hash_chain_length, block_hash_tree_length, - share_data_length, encprivkey_length): - post_offset = HEADER_LENGTH - offsets = {} - o1 = offsets['signature'] = post_offset + verification_key_length - o2 = offsets['share_hash_chain'] = o1 + signature_length - o3 = offsets['block_hash_tree'] = o2 + share_hash_chain_length - o4 = offsets['share_data'] = o3 + block_hash_tree_length - o5 = offsets['enc_privkey'] = o4 + share_data_length - o6 = offsets['EOF'] = o5 + encprivkey_length - - return struct.pack(">LLLLQQ", - offsets['signature'], - offsets['share_hash_chain'], - offsets['block_hash_tree'], - offsets['share_data'], - offsets['enc_privkey'], - offsets['EOF']) - -def pack_share(prefix, verification_key, signature, - share_hash_chain, block_hash_tree, - share_data, encprivkey): - share_hash_chain_s = "".join([struct.pack(">H32s", i, share_hash_chain[i]) - for i in sorted(share_hash_chain.keys())]) - for h in block_hash_tree: - assert len(h) == 32 - block_hash_tree_s = "".join(block_hash_tree) - - offsets = pack_offsets(len(verification_key), - len(signature), - len(share_hash_chain_s), - len(block_hash_tree_s), - len(share_data), - len(encprivkey)) - final_share = "".join([prefix, - offsets, - verification_key, - signature, - share_hash_chain_s, - block_hash_tree_s, - share_data, - encprivkey]) - return final_share - -class ServerMap: - """I record the placement of mutable shares. - - This object records which shares (of various versions) are located on - which servers. - - One purpose I serve is to inform callers about which versions of the - mutable file are recoverable and 'current'. - - A second purpose is to serve as a state marker for test-and-set - operations. I am passed out of retrieval operations and back into publish - operations, which means 'publish this new version, but only if nothing - has changed since I last retrieved this data'. This reduces the chances - of clobbering a simultaneous (uncoordinated) write. - """ - - def __init__(self): - # 'servermap' maps peerid to sets of (shnum, versionid, timestamp) - # tuples. Each 'versionid' is a (seqnum, root_hash, IV, segsize, - # datalength, k, N, signed_prefix, offsets) tuple - self.servermap = DictOfSets() - self.connections = {} # maps peerid to a RemoteReference - self.unreachable_peers = set() # peerids that didn't respond to queries - self.problems = [] # mostly for debugging - self.last_update_mode = None - self.last_update_time = 0 - - def dump(self, out=sys.stdout): - print >>out, "servermap:" - for (peerid, shares) in self.servermap.items(): - for (shnum, versionid, timestamp) in sorted(shares): - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = versionid - print >>out, ("[%s]: sh#%d seq%d-%s %d-of-%d len%d" % - (idlib.shortnodeid_b2a(peerid), shnum, - seqnum, base32.b2a(root_hash)[:4], k, N, - datalength)) - return out - - def make_versionmap(self): - """Return a dict that maps versionid to sets of (shnum, peerid, - timestamp) tuples.""" - versionmap = DictOfSets() - for (peerid, shares) in self.servermap.items(): - for (shnum, verinfo, timestamp) in shares: - versionmap.add(verinfo, (shnum, peerid, timestamp)) - return versionmap - - def shares_on_peer(self, peerid): - return set([shnum - for (shnum, versionid, timestamp) - in self.servermap.get(peerid, [])]) - - def version_on_peer(self, peerid, shnum): - shares = self.servermap.get(peerid, []) - for (sm_shnum, sm_versionid, sm_timestamp) in shares: - if sm_shnum == shnum: - return sm_versionid - return None - - def shares_available(self): - """Return a dict that maps versionid to tuples of - (num_distinct_shares, k) tuples.""" - versionmap = self.make_versionmap() - all_shares = {} - for versionid, shares in versionmap.items(): - s = set() - for (shnum, peerid, timestamp) in shares: - s.add(shnum) - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = versionid - all_shares[versionid] = (len(s), k) - return all_shares - - def highest_seqnum(self): - available = self.shares_available() - seqnums = [versionid[0] - for versionid in available.keys()] - seqnums.append(0) - return max(seqnums) - - def recoverable_versions(self): - """Return a set of versionids, one for each version that is currently - recoverable.""" - versionmap = self.make_versionmap() - - recoverable_versions = set() - for (verinfo, shares) in versionmap.items(): - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = verinfo - shnums = set([shnum for (shnum, peerid, timestamp) in shares]) - if len(shnums) >= k: - # this one is recoverable - recoverable_versions.add(verinfo) - - return recoverable_versions - - def unrecoverable_versions(self): - """Return a set of versionids, one for each version that is currently - unrecoverable.""" - versionmap = self.make_versionmap() - - unrecoverable_versions = set() - for (verinfo, shares) in versionmap.items(): - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = verinfo - shnums = set([shnum for (shnum, peerid, timestamp) in shares]) - if len(shnums) < k: - unrecoverable_versions.add(verinfo) - - return unrecoverable_versions - - def best_recoverable_version(self): - """Return a single versionid, for the so-called 'best' recoverable - version. Sequence number is the primary sort criteria, followed by - root hash. Returns None if there are no recoverable versions.""" - recoverable = list(self.recoverable_versions()) - recoverable.sort() - if recoverable: - return recoverable[-1] - return None - - def unrecoverable_newer_versions(self): - # Return a dict of versionid -> health, for versions that are - # unrecoverable and have later seqnums than any recoverable versions. - # These indicate that a write will lose data. - pass - - def needs_merge(self): - # return True if there are multiple recoverable versions with the - # same seqnum, meaning that MutableFileNode.read_best_version is not - # giving you the whole story, and that using its data to do a - # subsequent publish will lose information. - pass - - -class RetrieveStatus: - implements(IRetrieveStatus) - statusid_counter = count(0) - def __init__(self): - self.timings = {} - self.timings["fetch_per_server"] = {} - self.timings["cumulative_verify"] = 0.0 - self.sharemap = {} - self.problems = {} - self.active = True - self.storage_index = None - self.helper = False - self.encoding = ("?","?") - self.search_distance = None - self.size = None - self.status = "Not started" - self.progress = 0.0 - self.counter = self.statusid_counter.next() - self.started = time.time() - - def get_started(self): - return self.started - def get_storage_index(self): - return self.storage_index - def get_encoding(self): - return self.encoding - def get_search_distance(self): - return self.search_distance - def using_helper(self): - return self.helper - def get_size(self): - return self.size - def get_status(self): - return self.status - def get_progress(self): - return self.progress - def get_active(self): - return self.active - def get_counter(self): - return self.counter - - def set_storage_index(self, si): - self.storage_index = si - def set_helper(self, helper): - self.helper = helper - def set_encoding(self, k, n): - self.encoding = (k, n) - def set_search_distance(self, value): - self.search_distance = value - def set_size(self, size): - self.size = size - def set_status(self, status): - self.status = status - def set_progress(self, value): - self.progress = value - def set_active(self, value): - self.active = value - -MODE_CHECK = "query all peers" -MODE_ANYTHING = "one recoverable version" -MODE_WRITE = "replace all shares, probably" # not for initial creation -MODE_ENOUGH = "enough" - -class ServermapUpdater: - def __init__(self, filenode, servermap, mode=MODE_ENOUGH): - self._node = filenode - self._servermap = servermap - self.mode = mode - self._running = True - - self._storage_index = filenode.get_storage_index() - self._last_failure = None - - # how much data should we read? - # * if we only need the checkstring, then [0:75] - # * if we need to validate the checkstring sig, then [543ish:799ish] - # * if we need the verification key, then [107:436ish] - # * the offset table at [75:107] tells us about the 'ish' - # * if we need the encrypted private key, we want [-1216ish:] - # * but we can't read from negative offsets - # * the offset table tells us the 'ish', also the positive offset - # A future version of the SMDF slot format should consider using - # fixed-size slots so we can retrieve less data. For now, we'll just - # read 2000 bytes, which also happens to read enough actual data to - # pre-fetch a 9-entry dirnode. - self._read_size = 2000 - if mode == MODE_CHECK: - # we use unpack_prefix_and_signature, so we need 1k - self._read_size = 1000 - self._need_privkey = False - if mode == MODE_WRITE and not self._node._privkey: - self._need_privkey = True - - prefix = storage.si_b2a(self._storage_index)[:5] - self._log_number = log.msg("SharemapUpdater(%s): starting" % prefix) - - def log(self, *args, **kwargs): - if "parent" not in kwargs: - kwargs["parent"] = self._log_number - return log.msg(*args, **kwargs) - - def update(self): - """Update the servermap to reflect current conditions. Returns a - Deferred that fires with the servermap once the update has finished.""" - - # self._valid_versions is a set of validated verinfo tuples. We just - # use it to remember which versions had valid signatures, so we can - # avoid re-checking the signatures for each share. - self._valid_versions = set() - - # self.versionmap maps verinfo tuples to sets of (shnum, peerid, - # timestamp) tuples. This is used to figure out which versions might - # be retrievable, and to make the eventual data download faster. - self.versionmap = DictOfSets() - - self._started = time.time() - self._done_deferred = defer.Deferred() - - # first, which peers should be talk to? Any that were in our old - # servermap, plus "enough" others. - - self._queries_completed = 0 - - client = self._node._client - full_peerlist = client.get_permuted_peers("storage", - self._node._storage_index) - self.full_peerlist = full_peerlist # for use later, immutable - self.extra_peers = full_peerlist[:] # peers are removed as we use them - self._good_peers = set() # peers who had some shares - self._empty_peers = set() # peers who don't have any shares - self._bad_peers = set() # peers to whom our queries failed - - k = self._node.get_required_shares() - if k is None: - # make a guess - k = 3 - N = self._node.get_required_shares() - if N is None: - N = 10 - self.EPSILON = k - # we want to send queries to at least this many peers (although we - # might not wait for all of their answers to come back) - self.num_peers_to_query = k + self.EPSILON - - if self.mode == MODE_CHECK: - initial_peers_to_query = dict(full_peerlist) - must_query = set(initial_peers_to_query.keys()) - self.extra_peers = [] - elif self.mode == MODE_WRITE: - # we're planning to replace all the shares, so we want a good - # chance of finding them all. We will keep searching until we've - # seen epsilon that don't have a share. - self.num_peers_to_query = N + self.EPSILON - initial_peers_to_query, must_query = self._build_initial_querylist() - self.required_num_empty_peers = self.EPSILON - - # TODO: arrange to read lots of data from k-ish servers, to avoid - # the extra round trip required to read large directories. This - # might also avoid the round trip required to read the encrypted - # private key. - - else: - initial_peers_to_query, must_query = self._build_initial_querylist() - - # this is a set of peers that we are required to get responses from: - # they are peers who used to have a share, so we need to know where - # they currently stand, even if that means we have to wait for a - # silently-lost TCP connection to time out. We remove peers from this - # set as we get responses. - self._must_query = must_query - - # now initial_peers_to_query contains the peers that we should ask, - # self.must_query contains the peers that we must have heard from - # before we can consider ourselves finished, and self.extra_peers - # contains the overflow (peers that we should tap if we don't get - # enough responses) - - self._send_initial_requests(initial_peers_to_query) - return self._done_deferred - - def _build_initial_querylist(self): - initial_peers_to_query = {} - must_query = set() - for peerid in self._servermap.servermap.keys(): - ss = self._servermap.connections[peerid] - # we send queries to everyone who was already in the sharemap - initial_peers_to_query[peerid] = ss - # and we must wait for responses from them - must_query.add(peerid) - - while ((self.num_peers_to_query > len(initial_peers_to_query)) - and self.extra_peers): - (peerid, ss) = self.extra_peers.pop(0) - initial_peers_to_query[peerid] = ss - - return initial_peers_to_query, must_query - - def _send_initial_requests(self, peerlist): - self._queries_outstanding = set() - self._sharemap = DictOfSets() # shnum -> [(peerid, seqnum, R)..] - dl = [] - for (peerid, ss) in peerlist.items(): - self._queries_outstanding.add(peerid) - self._do_query(ss, peerid, self._storage_index, self._read_size) - - # control flow beyond this point: state machine. Receiving responses - # from queries is the input. We might send out more queries, or we - # might produce a result. - return None - - def _do_query(self, ss, peerid, storage_index, readsize): - self.log(format="sending query to [%(peerid)s], readsize=%(readsize)d", - peerid=idlib.shortnodeid_b2a(peerid), - readsize=readsize, - level=log.NOISY) - self._servermap.connections[peerid] = ss - started = time.time() - self._queries_outstanding.add(peerid) - d = self._do_read(ss, peerid, storage_index, [], [(0, readsize)]) - d.addCallback(self._got_results, peerid, readsize, (ss, storage_index), - started) - d.addErrback(self._query_failed, peerid) - # errors that aren't handled by _query_failed (and errors caused by - # _query_failed) get logged, but we still want to check for doneness. - d.addErrback(log.err) - d.addBoth(self._check_for_done) - d.addErrback(self._fatal_error) - return d - - def _do_read(self, ss, peerid, storage_index, shnums, readv): - d = ss.callRemote("slot_readv", storage_index, shnums, readv) - return d - - def _got_results(self, datavs, peerid, readsize, stuff, started): - lp = self.log(format="got result from [%(peerid)s], %(numshares)d shares", - peerid=idlib.shortnodeid_b2a(peerid), - numshares=len(datavs), - level=log.NOISY) - self._queries_outstanding.discard(peerid) - self._must_query.discard(peerid) - self._queries_completed += 1 - if not self._running: - self.log("but we're not running, so we'll ignore it") - return - - if datavs: - self._good_peers.add(peerid) - else: - self._empty_peers.add(peerid) - - last_verinfo = None - last_shnum = None - for shnum,datav in datavs.items(): - data = datav[0] - try: - verinfo = self._got_results_one_share(shnum, data, peerid) - last_verinfo = verinfo - last_shnum = shnum - except CorruptShareError, e: - # log it and give the other shares a chance to be processed - f = failure.Failure() - self.log("bad share: %s %s" % (f, f.value), level=log.WEIRD) - self._bad_peers.add(peerid) - self._last_failure = f - self._servermap.problems.append(f) - pass - - if self._need_privkey and last_verinfo: - # send them a request for the privkey. We send one request per - # server. - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = last_verinfo - o = dict(offsets_tuple) - - self._queries_outstanding.add(peerid) - readv = [ (o['enc_privkey'], (o['EOF'] - o['enc_privkey'])) ] - ss = self._servermap.connections[peerid] - d = self._do_read(ss, peerid, self._storage_index, - [last_shnum], readv) - d.addCallback(self._got_privkey_results, peerid, last_shnum) - d.addErrback(self._privkey_query_failed, peerid, last_shnum) - d.addErrback(log.err) - d.addCallback(self._check_for_done) - d.addErrback(self._fatal_error) - - # all done! - self.log("_got_results done", parent=lp) - - def _got_results_one_share(self, shnum, data, peerid): - self.log(format="_got_results: got shnum #%(shnum)d from peerid %(peerid)s", - shnum=shnum, - peerid=idlib.shortnodeid_b2a(peerid)) - - # this might raise NeedMoreDataError, if the pubkey and signature - # live at some weird offset. That shouldn't happen, so I'm going to - # treat it as a bad share. - (seqnum, root_hash, IV, k, N, segsize, datalength, - pubkey_s, signature, prefix) = unpack_prefix_and_signature(data) - - if not self._node._pubkey: - fingerprint = hashutil.ssk_pubkey_fingerprint_hash(pubkey_s) - assert len(fingerprint) == 32 - if fingerprint != self._node._fingerprint: - raise CorruptShareError(peerid, shnum, - "pubkey doesn't match fingerprint") - self._node._pubkey = self._deserialize_pubkey(pubkey_s) - - if self._need_privkey: - self._try_to_extract_privkey(data, peerid, shnum) - - (ig_version, ig_seqnum, ig_root_hash, ig_IV, ig_k, ig_N, - ig_segsize, ig_datalen, offsets) = unpack_header(data) - offsets_tuple = tuple( [(key,value) for key,value in offsets.items()] ) - - verinfo = (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) - - if verinfo not in self._valid_versions: - # it's a new pair. Verify the signature. - valid = self._node._pubkey.verify(prefix, signature) - if not valid: - raise CorruptShareError(peerid, shnum, "signature is invalid") - - # ok, it's a valid verinfo. Add it to the list of validated - # versions. - self.log(" found valid version %d-%s from %s-sh%d: %d-%d/%d/%d" - % (seqnum, base32.b2a(root_hash)[:4], - idlib.shortnodeid_b2a(peerid), shnum, - k, N, segsize, datalength)) - self._valid_versions.add(verinfo) - # We now know that this is a valid candidate verinfo. - - # Add the info to our servermap. - timestamp = time.time() - self._servermap.servermap.add(peerid, (shnum, verinfo, timestamp)) - # and the versionmap - self.versionmap.add(verinfo, (shnum, peerid, timestamp)) - return verinfo - - def _deserialize_pubkey(self, pubkey_s): - verifier = rsa.create_verifying_key_from_string(pubkey_s) - return verifier - - def _try_to_extract_privkey(self, data, peerid, shnum): - try: - r = unpack_share(data) - except NeedMoreDataError, e: - # this share won't help us. oh well. - offset = e.encprivkey_offset - length = e.encprivkey_length - self.log("shnum %d on peerid %s: share was too short (%dB) " - "to get the encprivkey; [%d:%d] ought to hold it" % - (shnum, idlib.shortnodeid_b2a(peerid), len(data), - offset, offset+length)) - # NOTE: if uncoordinated writes are taking place, someone might - # change the share (and most probably move the encprivkey) before - # we get a chance to do one of these reads and fetch it. This - # will cause us to see a NotEnoughPeersError(unable to fetch - # privkey) instead of an UncoordinatedWriteError . This is a - # nuisance, but it will go away when we move to DSA-based mutable - # files (since the privkey will be small enough to fit in the - # write cap). - - return - - (seqnum, root_hash, IV, k, N, segsize, datalen, - pubkey, signature, share_hash_chain, block_hash_tree, - share_data, enc_privkey) = r - - return self._try_to_validate_privkey(self, enc_privkey, peerid, shnum) - - def _try_to_validate_privkey(self, enc_privkey, peerid, shnum): - - alleged_privkey_s = self._node._decrypt_privkey(enc_privkey) - alleged_writekey = hashutil.ssk_writekey_hash(alleged_privkey_s) - if alleged_writekey != self._node.get_writekey(): - self.log("invalid privkey from %s shnum %d" % - (idlib.nodeid_b2a(peerid)[:8], shnum), level=log.WEIRD) - return - - # it's good - self.log("got valid privkey from shnum %d on peerid %s" % - (shnum, idlib.shortnodeid_b2a(peerid))) - privkey = rsa.create_signing_key_from_string(alleged_privkey_s) - self._node._populate_encprivkey(enc_privkey) - self._node._populate_privkey(privkey) - self._need_privkey = False - - - def _query_failed(self, f, peerid): - self.log("error during query: %s %s" % (f, f.value), level=log.WEIRD) - if not self._running: - return - self._must_query.discard(peerid) - self._queries_outstanding.discard(peerid) - self._bad_peers.add(peerid) - self._servermap.problems.append(f) - self._servermap.unreachable_peers.add(peerid) # TODO: overkill? - self._queries_completed += 1 - self._last_failure = f - - def _got_privkey_results(self, datavs, peerid, shnum): - self._queries_outstanding.discard(peerid) - if not self._need_privkey: - return - if shnum not in datavs: - self.log("privkey wasn't there when we asked it", level=log.WEIRD) - return - datav = datavs[shnum] - enc_privkey = datav[0] - self._try_to_validate_privkey(enc_privkey, peerid, shnum) - - def _privkey_query_failed(self, f, peerid, shnum): - self._queries_outstanding.discard(peerid) - self.log("error during privkey query: %s %s" % (f, f.value), - level=log.WEIRD) - if not self._running: - return - self._queries_outstanding.discard(peerid) - self._servermap.problems.append(f) - self._last_failure = f - - def _check_for_done(self, res): - # exit paths: - # return self._send_more_queries(outstanding) : send some more queries - # return self._done() : all done - # return : keep waiting, no new queries - - self.log(format=("_check_for_done, mode is '%(mode)s', " - "%(outstanding)d queries outstanding, " - "%(extra)d extra peers available, " - "%(must)d 'must query' peers left" - ), - mode=self.mode, - outstanding=len(self._queries_outstanding), - extra=len(self.extra_peers), - must=len(self._must_query), - ) - - if self._must_query: - # we are still waiting for responses from peers that used to have - # a share, so we must continue to wait. No additional queries are - # required at this time. - self.log("%d 'must query' peers left" % len(self._must_query)) - return - - if (not self._queries_outstanding and not self.extra_peers): - # all queries have retired, and we have no peers left to ask. No - # more progress can be made, therefore we are done. - self.log("all queries are retired, no extra peers: done") - return self._done() - - recoverable_versions = self._servermap.recoverable_versions() - unrecoverable_versions = self._servermap.unrecoverable_versions() - - # what is our completion policy? how hard should we work? - - if self.mode == MODE_ANYTHING: - if recoverable_versions: - self.log("MODE_ANYTHING and %d recoverable versions: done" - % len(recoverable_versions)) - return self._done() - - if self.mode == MODE_CHECK: - # we used self._must_query, and we know there aren't any - # responses still waiting, so that means we must be done - self.log("MODE_CHECK: done") - return self._done() - - MAX_IN_FLIGHT = 5 - if self.mode == MODE_ENOUGH: - # if we've queried k+epsilon servers, and we see a recoverable - # version, and we haven't seen any unrecoverable higher-seqnum'ed - # versions, then we're done. - - if self._queries_completed < self.num_peers_to_query: - self.log(format="ENOUGH, %(completed)d completed, %(query)d to query: need more", - completed=self._queries_completed, - query=self.num_peers_to_query) - return self._send_more_queries(MAX_IN_FLIGHT) - if not recoverable_versions: - self.log("ENOUGH, no recoverable versions: need more") - return self._send_more_queries(MAX_IN_FLIGHT) - highest_recoverable = max(recoverable_versions) - highest_recoverable_seqnum = highest_recoverable[0] - for unrec_verinfo in unrecoverable_versions: - if unrec_verinfo[0] > highest_recoverable_seqnum: - # there is evidence of a higher-seqnum version, but we - # don't yet see enough shares to recover it. Try harder. - # TODO: consider sending more queries. - # TODO: consider limiting the search distance - self.log("ENOUGH, evidence of higher seqnum: need more") - return self._send_more_queries(MAX_IN_FLIGHT) - # all the unrecoverable versions were old or concurrent with a - # recoverable version. Good enough. - self.log("ENOUGH: no higher-seqnum: done") - return self._done() - - if self.mode == MODE_WRITE: - # we want to keep querying until we've seen a few that don't have - # any shares, to be sufficiently confident that we've seen all - # the shares. This is still less work than MODE_CHECK, which asks - # every server in the world. - - if not recoverable_versions: - self.log("WRITE, no recoverable versions: need more") - return self._send_more_queries(MAX_IN_FLIGHT) - - last_found = -1 - last_not_responded = -1 - num_not_responded = 0 - num_not_found = 0 - states = [] - found_boundary = False - - for i,(peerid,ss) in enumerate(self.full_peerlist): - if peerid in self._bad_peers: - # query failed - states.append("x") - #self.log("loop [%s]: x" % idlib.shortnodeid_b2a(peerid)) - elif peerid in self._empty_peers: - # no shares - states.append("0") - #self.log("loop [%s]: 0" % idlib.shortnodeid_b2a(peerid)) - if last_found != -1: - num_not_found += 1 - if num_not_found >= self.EPSILON: - self.log("MODE_WRITE: found our boundary, %s" % - "".join(states)) - found_boundary = True - break - - elif peerid in self._good_peers: - # yes shares - states.append("1") - #self.log("loop [%s]: 1" % idlib.shortnodeid_b2a(peerid)) - last_found = i - num_not_found = 0 - else: - # not responded yet - states.append("?") - #self.log("loop [%s]: ?" % idlib.shortnodeid_b2a(peerid)) - last_not_responded = i - num_not_responded += 1 - - if found_boundary: - # we need to know that we've gotten answers from - # everybody to the left of here - if last_not_responded == -1: - # we're done - self.log("have all our answers") - # .. unless we're still waiting on the privkey - if self._need_privkey: - self.log("but we're still waiting for the privkey") - # if we found the boundary but we haven't yet found - # the privkey, we may need to look further. If - # somehow all the privkeys were corrupted (but the - # shares were readable), then this is likely to do an - # exhaustive search. - return self._send_more_queries(MAX_IN_FLIGHT) - return self._done() - # still waiting for somebody - return self._send_more_queries(num_not_responded) - - # if we hit here, we didn't find our boundary, so we're still - # waiting for peers - self.log("MODE_WRITE: no boundary yet, %s" % "".join(states)) - return self._send_more_queries(MAX_IN_FLIGHT) - - # otherwise, keep up to 5 queries in flight. TODO: this is pretty - # arbitrary, really I want this to be something like k - - # max(known_version_sharecounts) + some extra - self.log("catchall: need more") - return self._send_more_queries(MAX_IN_FLIGHT) - - def _send_more_queries(self, num_outstanding): - more_queries = [] - - while True: - self.log(format=" there are %(outstanding)d queries outstanding", - outstanding=len(self._queries_outstanding), - level=log.NOISY) - active_queries = len(self._queries_outstanding) + len(more_queries) - if active_queries >= num_outstanding: - break - if not self.extra_peers: - break - more_queries.append(self.extra_peers.pop(0)) - - self.log(format="sending %(more)d more queries: %(who)s", - more=len(more_queries), - who=" ".join(["[%s]" % idlib.shortnodeid_b2a(peerid) - for (peerid,ss) in more_queries]), - level=log.NOISY) - - for (peerid, ss) in more_queries: - self._do_query(ss, peerid, self._storage_index, self._read_size) - # we'll retrigger when those queries come back - - def _done(self): - if not self._running: - return - self._running = False - self._servermap.last_update_mode = self.mode - self._servermap.last_update_time = self._started - # the servermap will not be touched after this - eventually(self._done_deferred.callback, self._servermap) - - def _fatal_error(self, f): - self.log("fatal error", failure=f, level=log.WEIRD) - self._done_deferred.errback(f) - - -class Marker: - pass - -class Retrieve: - # this class is currently single-use. Eventually (in MDMF) we will make - # it multi-use, in which case you can call download(range) multiple - # times, and each will have a separate response chain. However the - # Retrieve object will remain tied to a specific version of the file, and - # will use a single ServerMap instance. - - def __init__(self, filenode, servermap, verinfo): - self._node = filenode - assert self._node._pubkey - self._storage_index = filenode.get_storage_index() - assert self._node._readkey - self._last_failure = None - prefix = storage.si_b2a(self._storage_index)[:5] - self._log_number = log.msg("Retrieve(%s): starting" % prefix) - self._outstanding_queries = {} # maps (peerid,shnum) to start_time - self._running = True - self._decoding = False - - self.servermap = servermap - assert self._node._pubkey - self.verinfo = verinfo - - def log(self, *args, **kwargs): - if "parent" not in kwargs: - kwargs["parent"] = self._log_number - return log.msg(*args, **kwargs) - - def download(self): - self._done_deferred = defer.Deferred() - - # first, which servers can we use? - versionmap = self.servermap.make_versionmap() - shares = versionmap[self.verinfo] - # this sharemap is consumed as we decide to send requests - self.remaining_sharemap = DictOfSets() - for (shnum, peerid, timestamp) in shares: - self.remaining_sharemap.add(shnum, peerid) - - self.shares = {} # maps shnum to validated blocks - - # how many shares do we need? - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = self.verinfo - assert len(self.remaining_sharemap) >= k - # we start with the lowest shnums we have available, since FEC is - # faster if we're using "primary shares" - self.active_shnums = set(sorted(self.remaining_sharemap.keys())[:k]) - for shnum in self.active_shnums: - # we use an arbitrary peer who has the share. If shares are - # doubled up (more than one share per peer), we could make this - # run faster by spreading the load among multiple peers. But the - # algorithm to do that is more complicated than I want to write - # right now, and a well-provisioned grid shouldn't have multiple - # shares per peer. - peerid = list(self.remaining_sharemap[shnum])[0] - self.get_data(shnum, peerid) - - # control flow beyond this point: state machine. Receiving responses - # from queries is the input. We might send out more queries, or we - # might produce a result. - - return self._done_deferred - - def get_data(self, shnum, peerid): - self.log(format="sending sh#%(shnum)d request to [%(peerid)s]", - shnum=shnum, - peerid=idlib.shortnodeid_b2a(peerid), - level=log.NOISY) - ss = self.servermap.connections[peerid] - started = time.time() - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = self.verinfo - offsets = dict(offsets_tuple) - # we read the checkstring, to make sure that the data we grab is from - # the right version. We also read the data, and the hashes necessary - # to validate them (share_hash_chain, block_hash_tree, share_data). - # We don't read the signature or the pubkey, since that was handled - # during the servermap phase, and we'll be comparing the share hash - # chain against the roothash that was validated back then. - readv = [ (0, struct.calcsize(SIGNED_PREFIX)), - (offsets['share_hash_chain'], - offsets['enc_privkey'] - offsets['share_hash_chain']), - ] - - m = Marker() - self._outstanding_queries[m] = (peerid, shnum, started) - - # ask the cache first - datav = [] - #for (offset, length) in readv: - # (data, timestamp) = self._node._cache.read(self.verinfo, shnum, - # offset, length) - # if data is not None: - # datav.append(data) - if len(datav) == len(readv): - self.log("got data from cache") - d = defer.succeed(datav) - else: - self.remaining_sharemap[shnum].remove(peerid) - d = self._do_read(ss, peerid, self._storage_index, [shnum], readv) - d.addCallback(self._fill_cache, readv) - - d.addCallback(self._got_results, m, peerid, started) - d.addErrback(self._query_failed, m, peerid) - # errors that aren't handled by _query_failed (and errors caused by - # _query_failed) get logged, but we still want to check for doneness. - def _oops(f): - self.log(format="problem in _query_failed for sh#%(shnum)d to %(peerid)s", - shnum=shnum, - peerid=idlib.shortnodeid_b2a(peerid), - failure=f, - level=log.WEIRD) - d.addErrback(_oops) - d.addBoth(self._check_for_done) - # any error during _check_for_done means the download fails. If the - # download is successful, _check_for_done will fire _done by itself. - d.addErrback(self._done) - d.addErrback(log.err) - return d # purely for testing convenience - - def _fill_cache(self, datavs, readv): - timestamp = time.time() - for shnum,datav in datavs.items(): - for i, (offset, length) in enumerate(readv): - data = datav[i] - self._node._cache.add(self.verinfo, shnum, offset, data, - timestamp) - return datavs - - def _do_read(self, ss, peerid, storage_index, shnums, readv): - # isolate the callRemote to a separate method, so tests can subclass - # Publish and override it - d = ss.callRemote("slot_readv", storage_index, shnums, readv) - return d - - def remove_peer(self, peerid): - for shnum in list(self.remaining_sharemap.keys()): - self.remaining_sharemap.discard(shnum, peerid) - - def _got_results(self, datavs, marker, peerid, started): - self.log(format="got results (%(shares)d shares) from [%(peerid)s]", - shares=len(datavs), - peerid=idlib.shortnodeid_b2a(peerid), - level=log.NOISY) - self._outstanding_queries.pop(marker, None) - if not self._running: - return - - # note that we only ask for a single share per query, so we only - # expect a single share back. On the other hand, we use the extra - # shares if we get them.. seems better than an assert(). - - for shnum,datav in datavs.items(): - (prefix, hash_and_data) = datav - try: - self._got_results_one_share(shnum, peerid, - prefix, hash_and_data) - except CorruptShareError, e: - # log it and give the other shares a chance to be processed - f = failure.Failure() - self.log("bad share: %s %s" % (f, f.value), level=log.WEIRD) - self.remove_peer(peerid) - self._last_failure = f - pass - # all done! - - def _got_results_one_share(self, shnum, peerid, - got_prefix, got_hash_and_data): - self.log("_got_results: got shnum #%d from peerid %s" - % (shnum, idlib.shortnodeid_b2a(peerid))) - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = self.verinfo - assert len(got_prefix) == len(prefix), (len(got_prefix), len(prefix)) - if got_prefix != prefix: - msg = "someone wrote to the data since we read the servermap: prefix changed" - raise UncoordinatedWriteError(msg) - (share_hash_chain, block_hash_tree, - share_data) = unpack_share_data(self.verinfo, got_hash_and_data) - - assert isinstance(share_data, str) - # build the block hash tree. SDMF has only one leaf. - leaves = [hashutil.block_hash(share_data)] - t = hashtree.HashTree(leaves) - if list(t) != block_hash_tree: - raise CorruptShareError(peerid, shnum, "block hash tree failure") - share_hash_leaf = t[0] - t2 = hashtree.IncompleteHashTree(N) - # root_hash was checked by the signature - t2.set_hashes({0: root_hash}) - try: - t2.set_hashes(hashes=share_hash_chain, - leaves={shnum: share_hash_leaf}) - except (hashtree.BadHashError, hashtree.NotEnoughHashesError, - IndexError), e: - msg = "corrupt hashes: %s" % (e,) - raise CorruptShareError(peerid, shnum, msg) - self.log(" data valid! len=%d" % len(share_data)) - # each query comes down to this: placing validated share data into - # self.shares - self.shares[shnum] = share_data - - def _query_failed(self, f, marker, peerid): - self.log(format="query to [%(peerid)s] failed", - peerid=idlib.shortnodeid_b2a(peerid), - level=log.NOISY) - self._outstanding_queries.pop(marker, None) - if not self._running: - return - self._last_failure = f - self.remove_peer(peerid) - self.log("error during query: %s %s" % (f, f.value), level=log.WEIRD) - - def _check_for_done(self, res): - # exit paths: - # return : keep waiting, no new queries - # return self._send_more_queries(outstanding) : send some more queries - # fire self._done(plaintext) : download successful - # raise exception : download fails - - self.log(format="_check_for_done: running=%(running)s, decoding=%(decoding)s", - running=self._running, decoding=self._decoding, - level=log.NOISY) - if not self._running: - return - if self._decoding: - return - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = self.verinfo - - if len(self.shares) < k: - # we don't have enough shares yet - return self._maybe_send_more_queries(k) - - # we have enough to finish. All the shares have had their hashes - # checked, so if something fails at this point, we don't know how - # to fix it, so the download will fail. - - self._decoding = True # avoid reentrancy - - d = defer.maybeDeferred(self._decode) - d.addCallback(self._decrypt, IV, self._node._readkey) - d.addBoth(self._done) - return d # purely for test convenience - - def _maybe_send_more_queries(self, k): - # we don't have enough shares yet. Should we send out more queries? - # There are some number of queries outstanding, each for a single - # share. If we can generate 'needed_shares' additional queries, we do - # so. If we can't, then we know this file is a goner, and we raise - # NotEnoughPeersError. - self.log(format=("_maybe_send_more_queries, have=%(have)d, k=%(k)d, " - "outstanding=%(outstanding)d"), - have=len(self.shares), k=k, - outstanding=len(self._outstanding_queries), - level=log.NOISY) - - remaining_shares = k - len(self.shares) - needed = remaining_shares - len(self._outstanding_queries) - if not needed: - # we have enough queries in flight already - - # TODO: but if they've been in flight for a long time, and we - # have reason to believe that new queries might respond faster - # (i.e. we've seen other queries come back faster, then consider - # sending out new queries. This could help with peers which have - # silently gone away since the servermap was updated, for which - # we're still waiting for the 15-minute TCP disconnect to happen. - self.log("enough queries are in flight, no more are needed", - level=log.NOISY) - return - - outstanding_shnums = set([shnum - for (peerid, shnum, started) - in self._outstanding_queries.values()]) - # prefer low-numbered shares, they are more likely to be primary - available_shnums = sorted(self.remaining_sharemap.keys()) - for shnum in available_shnums: - if shnum in outstanding_shnums: - # skip ones that are already in transit - continue - if shnum not in self.remaining_sharemap: - # no servers for that shnum. note that DictOfSets removes - # empty sets from the dict for us. - continue - peerid = list(self.remaining_sharemap[shnum])[0] - # get_data will remove that peerid from the sharemap, and add the - # query to self._outstanding_queries - self.get_data(shnum, peerid) - needed -= 1 - if not needed: - break - - # at this point, we have as many outstanding queries as we can. If - # needed!=0 then we might not have enough to recover the file. - if needed: - format = ("ran out of peers: " - "have %(have)d shares (k=%(k)d), " - "%(outstanding)d queries in flight, " - "need %(need)d more") - self.log(format=format, - have=len(self.shares), k=k, - outstanding=len(self._outstanding_queries), - need=needed, - level=log.WEIRD) - msg2 = format % {"have": len(self.shares), - "k": k, - "outstanding": len(self._outstanding_queries), - "need": needed, - } - raise NotEnoughPeersError("%s, last failure: %s" % - (msg2, self._last_failure)) - - return - - def _decode(self): - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = self.verinfo - - # shares_dict is a dict mapping shnum to share data, but the codec - # wants two lists. - shareids = []; shares = [] - for shareid, share in self.shares.items(): - shareids.append(shareid) - shares.append(share) - - assert len(shareids) >= k, len(shareids) - # zfec really doesn't want extra shares - shareids = shareids[:k] - shares = shares[:k] - - fec = codec.CRSDecoder() - params = "%d-%d-%d" % (segsize, k, N) - fec.set_serialized_params(params) - - self.log("params %s, we have %d shares" % (params, len(shares))) - self.log("about to decode, shareids=%s" % (shareids,)) - d = defer.maybeDeferred(fec.decode, shares, shareids) - def _done(buffers): - self.log(" decode done, %d buffers" % len(buffers)) - segment = "".join(buffers) - self.log(" joined length %d, datalength %d" % - (len(segment), datalength)) - segment = segment[:datalength] - self.log(" segment len=%d" % len(segment)) - return segment - def _err(f): - self.log(" decode failed: %s" % f) - return f - d.addCallback(_done) - d.addErrback(_err) - return d - - def _decrypt(self, crypttext, IV, readkey): - started = time.time() - key = hashutil.ssk_readkey_data_hash(IV, readkey) - decryptor = AES(key) - plaintext = decryptor.process(crypttext) - return plaintext - - def _done(self, res): - if not self._running: - return - self._running = False - # res is either the new contents, or a Failure - if isinstance(res, failure.Failure): - self.log("Retrieve done, with failure", failure=res) - else: - self.log("Retrieve done, success!: res=%s" % (res,)) - # remember the encoding parameters, use them again next time - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = self.verinfo - self._node._populate_required_shares(k) - self._node._populate_total_shares(N) - eventually(self._done_deferred.callback, res) - - -class PublishStatus: - implements(IPublishStatus) - statusid_counter = count(0) - def __init__(self): - self.timings = {} - self.timings["per_server"] = {} - self.privkey_from = None - self.peers_queried = None - self.sharemap = None # DictOfSets - self.problems = {} - self.active = True - self.storage_index = None - self.helper = False - self.encoding = ("?", "?") - self.initial_read_size = None - self.size = None - self.status = "Not started" - self.progress = 0.0 - self.counter = self.statusid_counter.next() - self.started = time.time() - - def add_per_server_time(self, peerid, op, elapsed): - assert op in ("read", "write") - if peerid not in self.timings["per_server"]: - self.timings["per_server"][peerid] = [] - self.timings["per_server"][peerid].append((op,elapsed)) - - def get_started(self): - return self.started - def get_storage_index(self): - return self.storage_index - def get_encoding(self): - return self.encoding - def using_helper(self): - return self.helper - def get_size(self): - return self.size - def get_status(self): - return self.status - def get_progress(self): - return self.progress - def get_active(self): - return self.active - def get_counter(self): - return self.counter - - def set_storage_index(self, si): - self.storage_index = si - def set_helper(self, helper): - self.helper = helper - def set_encoding(self, k, n): - self.encoding = (k, n) - def set_size(self, size): - self.size = size - def set_status(self, status): - self.status = status - def set_progress(self, value): - self.progress = value - def set_active(self, value): - self.active = value - -class Publish: - """I represent a single act of publishing the mutable file to the grid. I - will only publish my data if the servermap I am using still represents - the current state of the world. - - To make the initial publish, set servermap to None. - """ - - # we limit the segment size as usual to constrain our memory footprint. - # The max segsize is higher for mutable files, because we want to support - # dirnodes with up to 10k children, and each child uses about 330 bytes. - # If you actually put that much into a directory you'll be using a - # footprint of around 14MB, which is higher than we'd like, but it is - # more important right now to support large directories than to make - # memory usage small when you use them. Once we implement MDMF (with - # multiple segments), we will drop this back down, probably to 128KiB. - MAX_SEGMENT_SIZE = 3500000 - - def __init__(self, filenode, servermap): - self._node = filenode - self._servermap = servermap - self._storage_index = self._node.get_storage_index() - self._log_prefix = prefix = storage.si_b2a(self._storage_index)[:5] - num = self._node._client.log("Publish(%s): starting" % prefix) - self._log_number = num - self._running = True - - def log(self, *args, **kwargs): - if 'parent' not in kwargs: - kwargs['parent'] = self._log_number - return log.msg(*args, **kwargs) - - def log_err(self, *args, **kwargs): - if 'parent' not in kwargs: - kwargs['parent'] = self._log_number - return log.err(*args, **kwargs) - - def publish(self, newdata): - """Publish the filenode's current contents. Returns a Deferred that - fires (with None) when the publish has done as much work as it's ever - going to do, or errbacks with ConsistencyError if it detects a - simultaneous write. - """ - - # 1: generate shares (SDMF: files are small, so we can do it in RAM) - # 2: perform peer selection, get candidate servers - # 2a: send queries to n+epsilon servers, to determine current shares - # 2b: based upon responses, create target map - # 3: send slot_testv_and_readv_and_writev messages - # 4: as responses return, update share-dispatch table - # 4a: may need to run recovery algorithm - # 5: when enough responses are back, we're done - - self.log("starting publish, datalen is %s" % len(newdata)) - - self.done_deferred = defer.Deferred() - - self._writekey = self._node.get_writekey() - assert self._writekey, "need write capability to publish" - - # first, which servers will we publish to? We require that the - # servermap was updated in MODE_WRITE, so we can depend upon the - # peerlist computed by that process instead of computing our own. - if self._servermap: - assert self._servermap.last_update_mode == MODE_WRITE - # we will push a version that is one larger than anything present - # in the grid, according to the servermap. - self._new_seqnum = self._servermap.highest_seqnum() + 1 - else: - # If we don't have a servermap, that's because we're doing the - # initial publish - self._new_seqnum = 1 - self._servermap = ServerMap() - - self.log(format="new seqnum will be %(seqnum)d", - seqnum=self._new_seqnum, level=log.NOISY) - - # having an up-to-date servermap (or using a filenode that was just - # created for the first time) also guarantees that the following - # fields are available - self.readkey = self._node.get_readkey() - self.required_shares = self._node.get_required_shares() - assert self.required_shares is not None - self.total_shares = self._node.get_total_shares() - assert self.total_shares is not None - self._pubkey = self._node.get_pubkey() - assert self._pubkey - self._privkey = self._node.get_privkey() - assert self._privkey - self._encprivkey = self._node.get_encprivkey() - - client = self._node._client - full_peerlist = client.get_permuted_peers("storage", - self._storage_index) - self.full_peerlist = full_peerlist # for use later, immutable - self.bad_peers = set() # peerids who have errbacked/refused requests - - started = time.time() - dl = [] - for permutedid, (peerid, ss) in enumerate(partial_peerlist): - self._storage_servers[peerid] = ss - d = self._do_query(ss, peerid, storage_index) - d.addCallback(self._got_query_results, - peerid, permutedid, - reachable_peers, current_share_peers, started) - dl.append(d) - d = defer.DeferredList(dl) - d.addCallback(self._got_all_query_results, - total_shares, reachable_peers, - current_share_peers) - # TODO: add an errback too, probably to ignore that peer - - self.setup_encoding_parameters() - - self.surprised = False - - # we keep track of three tables. The first is our goal: which share - # we want to see on which servers. This is initially populated by the - # existing servermap. - self.goal = set() # pairs of (peerid, shnum) tuples - - # the second table is our list of outstanding queries: those which - # are in flight and may or may not be delivered, accepted, or - # acknowledged. Items are added to this table when the request is - # sent, and removed when the response returns (or errbacks). - self.outstanding = set() # (peerid, shnum) tuples - - # the third is a table of successes: share which have actually been - # placed. These are populated when responses come back with success. - # When self.placed == self.goal, we're done. - self.placed = set() # (peerid, shnum) tuples - - # we also keep a mapping from peerid to RemoteReference. Each time we - # pull a connection out of the full peerlist, we add it to this for - # use later. - self.connections = {} - - # we use the servermap to populate the initial goal: this way we will - # try to update each existing share in place. - for (peerid, shares) in self._servermap.servermap.items(): - for (shnum, versionid, timestamp) in shares: - self.goal.add( (peerid, shnum) ) - self.connections[peerid] = self._servermap.connections[peerid] - - # create the shares. We'll discard these as they are delivered. SMDF: - # we're allowed to hold everything in memory. - - d = self._encrypt_and_encode() - d.addCallback(self._generate_shares) - d.addCallback(self.loop) # trigger delivery - d.addErrback(self._fatal_error) - - return self.done_deferred - - def setup_encoding_parameters(self): - segment_size = min(self.MAX_SEGMENT_SIZE, len(self.newdata)) - # this must be a multiple of self.required_shares - segment_size = mathutil.next_multiple(segment_size, - self.required_shares) - self.segment_size = segment_size - if segment_size: - self.num_segments = mathutil.div_ceil(len(self.newdata), - segment_size) - else: - self.num_segments = 0 - assert self.num_segments in [0, 1,] # SDMF restrictions - - def _fatal_error(self, f): - self.log("error during loop", failure=f, level=log.SCARY) - self._done(f) - - def loop(self, ignored=None): - self.log("entering loop", level=log.NOISY) - self.update_goal() - # how far are we from our goal? - needed = self.goal - self.placed - self.outstanding - - if needed: - # we need to send out new shares - self.log(format="need to send %(needed)d new shares", - needed=len(needed), level=log.NOISY) - d = self._send_shares(needed) - d.addCallback(self.loop) - d.addErrback(self._fatal_error) - return - - if self.outstanding: - # queries are still pending, keep waiting - self.log(format="%(outstanding)d queries still outstanding", - outstanding=len(self.outstanding), - level=log.NOISY) - return - - # no queries outstanding, no placements needed: we're done - self.log("no queries outstanding, no placements needed: done", - level=log.OPERATIONAL) - return self._done(None) - - def log_goal(self, goal): - logmsg = [] - for (peerid, shnum) in goal: - logmsg.append("sh%d to [%s]" % (shnum, - idlib.shortnodeid_b2a(peerid))) - self.log("current goal: %s" % (", ".join(logmsg)), level=log.NOISY) - self.log("we are planning to push new seqnum=#%d" % self._new_seqnum, - level=log.NOISY) - - def update_goal(self): - # first, remove any bad peers from our goal - self.goal = set([ (peerid, shnum) - for (peerid, shnum) in self.goal - if peerid not in self.bad_peers ]) - - # find the homeless shares: - homefull_shares = set([shnum for (peerid, shnum) in self.goal]) - homeless_shares = set(range(self.total_shares)) - homefull_shares - homeless_shares = sorted(list(homeless_shares)) - # place them somewhere. We prefer unused servers at the beginning of - # the available peer list. - - if not homeless_shares: - return - - # if log.recording_noisy - if False: - self.log_goal(self.goal) - - # if an old share X is on a node, put the new share X there too. - # TODO: 1: redistribute shares to achieve one-per-peer, by copying - # shares from existing peers to new (less-crowded) ones. The - # old shares must still be updated. - # TODO: 2: move those shares instead of copying them, to reduce future - # update work - - # this is a bit CPU intensive but easy to analyze. We create a sort - # order for each peerid. If the peerid is marked as bad, we don't - # even put them in the list. Then we care about the number of shares - # which have already been assigned to them. After that we care about - # their permutation order. - old_assignments = DictOfSets() - for (peerid, shnum) in self.goal: - old_assignments.add(peerid, shnum) - - peerlist = [] - for i, (peerid, ss) in enumerate(self.full_peerlist): - entry = (len(old_assignments.get(peerid, [])), i, peerid, ss) - peerlist.append(entry) - peerlist.sort() - - new_assignments = [] - # we then index this peerlist with an integer, because we may have to - # wrap. We update the goal as we go. - i = 0 - for shnum in homeless_shares: - (ignored1, ignored2, peerid, ss) = peerlist[i] - self.goal.add( (peerid, shnum) ) - self.connections[peerid] = ss - i += 1 - if i >= len(peerlist): - i = 0 - - - - def _encrypt_and_encode(self): - # this returns a Deferred that fires with a list of (sharedata, - # sharenum) tuples. TODO: cache the ciphertext, only produce the - # shares that we care about. - self.log("_encrypt_and_encode") - - #started = time.time() - - key = hashutil.ssk_readkey_data_hash(self.salt, self.readkey) - enc = AES(key) - crypttext = enc.process(self.newdata) - assert len(crypttext) == len(self.newdata) - - #now = time.time() - #self._status.timings["encrypt"] = now - started - #started = now - - # now apply FEC - - fec = codec.CRSEncoder() - fec.set_params(self.segment_size, - self.required_shares, self.total_shares) - piece_size = fec.get_block_size() - crypttext_pieces = [None] * self.required_shares - for i in range(len(crypttext_pieces)): - offset = i * piece_size - piece = crypttext[offset:offset+piece_size] - piece = piece + "\x00"*(piece_size - len(piece)) # padding - crypttext_pieces[i] = piece - assert len(piece) == piece_size - - d = fec.encode(crypttext_pieces) - def _done_encoding(res): - #elapsed = time.time() - started - #self._status.timings["encode"] = elapsed - return res - d.addCallback(_done_encoding) - return d - - def _generate_shares(self, shares_and_shareids): - # this sets self.shares and self.root_hash - self.log("_generate_shares") - #started = time.time() - - # we should know these by now - privkey = self._privkey - encprivkey = self._encprivkey - pubkey = self._pubkey - - (shares, share_ids) = shares_and_shareids - - assert len(shares) == len(share_ids) - assert len(shares) == self.total_shares - all_shares = {} - block_hash_trees = {} - share_hash_leaves = [None] * len(shares) - for i in range(len(shares)): - share_data = shares[i] - shnum = share_ids[i] - all_shares[shnum] = share_data - - # build the block hash tree. SDMF has only one leaf. - leaves = [hashutil.block_hash(share_data)] - t = hashtree.HashTree(leaves) - block_hash_trees[shnum] = block_hash_tree = list(t) - share_hash_leaves[shnum] = t[0] - for leaf in share_hash_leaves: - assert leaf is not None - share_hash_tree = hashtree.HashTree(share_hash_leaves) - share_hash_chain = {} - for shnum in range(self.total_shares): - needed_hashes = share_hash_tree.needed_hashes(shnum) - share_hash_chain[shnum] = dict( [ (i, share_hash_tree[i]) - for i in needed_hashes ] ) - root_hash = share_hash_tree[0] - assert len(root_hash) == 32 - self.log("my new root_hash is %s" % base32.b2a(root_hash)) - - prefix = pack_prefix(self._new_seqnum, root_hash, self.salt, - self.required_shares, self.total_shares, - self.segment_size, len(self.newdata)) - - # now pack the beginning of the share. All shares are the same up - # to the signature, then they have divergent share hash chains, - # then completely different block hash trees + salt + share data, - # then they all share the same encprivkey at the end. The sizes - # of everything are the same for all shares. - - #sign_started = time.time() - signature = privkey.sign(prefix) - #self._status.timings["sign"] = time.time() - sign_started - - verification_key = pubkey.serialize() - - final_shares = {} - for shnum in range(self.total_shares): - final_share = pack_share(prefix, - verification_key, - signature, - share_hash_chain[shnum], - block_hash_trees[shnum], - all_shares[shnum], - encprivkey) - final_shares[shnum] = final_share - #elapsed = time.time() - started - #self._status.timings["pack"] = elapsed - self.shares = final_shares - self.root_hash = root_hash - - # we also need to build up the version identifier for what we're - # pushing. Extract the offsets from one of our shares. - assert final_shares - offsets = unpack_header(final_shares.values()[0])[-1] - offsets_tuple = tuple( [(key,value) for key,value in offsets.items()] ) - verinfo = (self._new_seqnum, root_hash, self.salt, - self.segment_size, len(self.newdata), - self.required_shares, self.total_shares, - prefix, offsets_tuple) - self.versioninfo = verinfo - - - - def _send_shares(self, needed): - self.log("_send_shares") - #started = time.time() - - # we're finally ready to send out our shares. If we encounter any - # surprises here, it's because somebody else is writing at the same - # time. (Note: in the future, when we remove the _query_peers() step - # and instead speculate about [or remember] which shares are where, - # surprises here are *not* indications of UncoordinatedWriteError, - # and we'll need to respond to them more gracefully.) - - # needed is a set of (peerid, shnum) tuples. The first thing we do is - # organize it by peerid. - - peermap = DictOfSets() - for (peerid, shnum) in needed: - peermap.add(peerid, shnum) - - # the next thing is to build up a bunch of test vectors. The - # semantics of Publish are that we perform the operation if the world - # hasn't changed since the ServerMap was constructed (more or less). - # For every share we're trying to place, we create a test vector that - # tests to see if the server*share still corresponds to the - # map. - - all_tw_vectors = {} # maps peerid to tw_vectors - sm = self._servermap.servermap - - for (peerid, shnum) in needed: - testvs = [] - for (old_shnum, old_versionid, old_timestamp) in sm.get(peerid,[]): - if old_shnum == shnum: - # an old version of that share already exists on the - # server, according to our servermap. We will create a - # request that attempts to replace it. - (old_seqnum, old_root_hash, old_salt, old_segsize, - old_datalength, old_k, old_N, old_prefix, - old_offsets_tuple) = old_versionid - old_checkstring = pack_checkstring(old_seqnum, - old_root_hash, - old_salt) - testv = (0, len(old_checkstring), "eq", old_checkstring) - testvs.append(testv) - break - if not testvs: - # add a testv that requires the share not exist - #testv = (0, 1, 'eq', "") - - # Unfortunately, foolscap-0.2.5 has a bug in the way inbound - # constraints are handled. If the same object is referenced - # multiple times inside the arguments, foolscap emits a - # 'reference' token instead of a distinct copy of the - # argument. The bug is that these 'reference' tokens are not - # accepted by the inbound constraint code. To work around - # this, we need to prevent python from interning the - # (constant) tuple, by creating a new copy of this vector - # each time. This bug is fixed in later versions of foolscap. - testv = tuple([0, 1, 'eq', ""]) - testvs.append(testv) - - # the write vector is simply the share - writev = [(0, self.shares[shnum])] - - if peerid not in all_tw_vectors: - all_tw_vectors[peerid] = {} - # maps shnum to (testvs, writevs, new_length) - assert shnum not in all_tw_vectors[peerid] - - all_tw_vectors[peerid][shnum] = (testvs, writev, None) - - # we read the checkstring back from each share, however we only use - # it to detect whether there was a new share that we didn't know - # about. The success or failure of the write will tell us whether - # there was a collision or not. If there is a collision, the first - # thing we'll do is update the servermap, which will find out what - # happened. We could conceivably reduce a roundtrip by using the - # readv checkstring to populate the servermap, but really we'd have - # to read enough data to validate the signatures too, so it wouldn't - # be an overall win. - read_vector = [(0, struct.calcsize(SIGNED_PREFIX))] - - # ok, send the messages! - started = time.time() - dl = [] - for (peerid, tw_vectors) in all_tw_vectors.items(): - - write_enabler = self._node.get_write_enabler(peerid) - renew_secret = self._node.get_renewal_secret(peerid) - cancel_secret = self._node.get_cancel_secret(peerid) - secrets = (write_enabler, renew_secret, cancel_secret) - shnums = tw_vectors.keys() - - d = self._do_testreadwrite(peerid, secrets, - tw_vectors, read_vector) - d.addCallbacks(self._got_write_answer, self._got_write_error, - callbackArgs=(peerid, shnums, started), - errbackArgs=(peerid, shnums, started)) - d.addErrback(self._fatal_error) - dl.append(d) - - d = defer.DeferredList(dl) - def _done_sending(res): - elapsed = time.time() - started - self._status.timings["push"] = elapsed - self._status.sharemap = dispatch_map - return res - d.addCallback(_done_sending) - d.addCallback(lambda res: (self._surprised, dispatch_map)) - return d - - def _do_testreadwrite(self, peerid, secrets, - tw_vectors, read_vector): - storage_index = self._storage_index - ss = self.connections[peerid] - - #print "SS[%s] is %s" % (idlib.shortnodeid_b2a(peerid), ss), ss.tracker.interfaceName - d = ss.callRemote("slot_testv_and_readv_and_writev", - storage_index, - secrets, - tw_vectors, - read_vector) - return d - - def _got_write_answer(self, answer, peerid, shnums, started): - lp = self.log("_got_write_answer from %s" % - idlib.shortnodeid_b2a(peerid)) - for shnum in shnums: - self.outstanding.discard( (peerid, shnum) ) - sm = self._servermap.servermap - - wrote, read_data = answer - - if not wrote: - self.log("our testv failed, so the write did not happen", - parent=lp, level=log.WEIRD) - self.surprised = True - self.bad_peers.add(peerid) # don't ask them again - # use the checkstring to add information to the log message - for (shnum,readv) in read_data.items(): - checkstring = readv[0] - (other_seqnum, - other_roothash, - other_salt) = unpack_checkstring(checkstring) - expected_version = self._servermap.version_on_peer(peerid, - shnum) - (seqnum, root_hash, IV, segsize, datalength, k, N, prefix, - offsets_tuple) = expected_version - self.log("somebody modified the share on us:" - " shnum=%d: I thought they had #%d:R=%s," - " but testv reported #%d:R=%s" % - (shnum, - seqnum, base32.b2a(root_hash)[:4], - other_seqnum, base32.b2a(other_roothash)[:4]), - parent=lp, level=log.NOISY) - # self.loop() will take care of finding new homes - return - - for shnum in shnums: - self.placed.add( (peerid, shnum) ) - # and update the servermap. We strip the old entry out.. - newset = set([ t - for t in sm.get(peerid, []) - if t[0] != shnum ]) - sm[peerid] = newset - # and add a new one - sm[peerid].add( (shnum, self.versioninfo, started) ) - - surprise_shares = set(read_data.keys()) - set(shnums) - if surprise_shares: - self.log("they had shares %s that we didn't know about" % - (list(surprise_shares),), - parent=lp, level=log.WEIRD) - self.surprised = True - return - - # self.loop() will take care of checking to see if we're done - return - - def _got_write_error(self, f, peerid, shnums, started): - for shnum in shnums: - self.outstanding.discard( (peerid, shnum) ) - self.bad_peers.add(peerid) - self.log(format="error while writing shares %(shnums)s to peerid %(peerid)s", - shnums=list(shnums), peerid=idlib.shortnodeid_b2a(peerid), - failure=f, - level=log.UNUSUAL) - # self.loop() will take care of checking to see if we're done - return - - - - def _log_dispatch_map(self, dispatch_map): - for shnum, places in dispatch_map.items(): - sent_to = [(idlib.shortnodeid_b2a(peerid), - seqnum, - base32.b2a(root_hash)[:4]) - for (peerid,seqnum,root_hash) in places] - self.log(" share %d sent to: %s" % (shnum, sent_to), - level=log.NOISY) - - def _maybe_recover(self, (surprised, dispatch_map)): - self.log("_maybe_recover, surprised=%s, dispatch_map:" % surprised, - level=log.NOISY) - self._log_dispatch_map(dispatch_map) - if not surprised: - self.log(" no recovery needed") - return - self.log("We need recovery!", level=log.WEIRD) - print "RECOVERY NOT YET IMPLEMENTED" - # but dispatch_map will help us do it - raise UncoordinatedWriteError("I was surprised!") - - def _done(self, res): - if not self._running: - return - self._running = False - #now = time.time() - #self._status.timings["total"] = now - self._started - #self._status.set_active(False) - #self._status.set_status("Done") - #self._status.set_progress(1.0) - self.done_deferred.callback(res) - return None - - def get_status(self): - return self._status - - - -# use client.create_mutable_file() to make one of these - -class MutableFileNode: - implements(IMutableFileNode) - publish_class = Publish - retrieve_class = Retrieve - SIGNATURE_KEY_SIZE = 2048 - DEFAULT_ENCODING = (3, 10) - - def __init__(self, client): - self._client = client - self._pubkey = None # filled in upon first read - self._privkey = None # filled in if we're mutable - # we keep track of the last encoding parameters that we use. These - # are updated upon retrieve, and used by publish. If we publish - # without ever reading (i.e. overwrite()), then we use these values. - (self._required_shares, self._total_shares) = self.DEFAULT_ENCODING - self._sharemap = {} # known shares, shnum-to-[nodeids] - self._cache = ResponseCache() - - self._current_data = None # SDMF: we're allowed to cache the contents - self._current_roothash = None # ditto - self._current_seqnum = None # ditto - - def __repr__(self): - return "<%s %x %s %s>" % (self.__class__.__name__, id(self), self.is_readonly() and 'RO' or 'RW', hasattr(self, '_uri') and self._uri.abbrev()) - - def init_from_uri(self, myuri): - # we have the URI, but we have not yet retrieved the public - # verification key, nor things like 'k' or 'N'. If and when someone - # wants to get our contents, we'll pull from shares and fill those - # in. - self._uri = IMutableFileURI(myuri) - if not self._uri.is_readonly(): - self._writekey = self._uri.writekey - self._readkey = self._uri.readkey - self._storage_index = self._uri.storage_index - self._fingerprint = self._uri.fingerprint - # the following values are learned during Retrieval - # self._pubkey - # self._required_shares - # self._total_shares - # and these are needed for Publish. They are filled in by Retrieval - # if possible, otherwise by the first peer that Publish talks to. - self._privkey = None - self._encprivkey = None - return self - - def create(self, initial_contents, keypair_generator=None): - """Call this when the filenode is first created. This will generate - the keys, generate the initial shares, wait until at least numpeers - are connected, allocate shares, and upload the initial - contents. Returns a Deferred that fires (with the MutableFileNode - instance you should use) when it completes. - """ - self._required_shares, self._total_shares = self.DEFAULT_ENCODING - - d = defer.maybeDeferred(self._generate_pubprivkeys, keypair_generator) - def _generated( (pubkey, privkey) ): - self._pubkey, self._privkey = pubkey, privkey - pubkey_s = self._pubkey.serialize() - privkey_s = self._privkey.serialize() - self._writekey = hashutil.ssk_writekey_hash(privkey_s) - self._encprivkey = self._encrypt_privkey(self._writekey, privkey_s) - self._fingerprint = hashutil.ssk_pubkey_fingerprint_hash(pubkey_s) - self._uri = WriteableSSKFileURI(self._writekey, self._fingerprint) - self._readkey = self._uri.readkey - self._storage_index = self._uri.storage_index - # TODO: seqnum/roothash: really we mean "doesn't matter since - # nobody knows about us yet" - self._current_seqnum = 0 - self._current_roothash = "\x00"*32 - return self._publish(initial_contents) - d.addCallback(_generated) - return d - - def _generate_pubprivkeys(self, keypair_generator): - if keypair_generator: - return keypair_generator(self.SIGNATURE_KEY_SIZE) - else: - # RSA key generation for a 2048 bit key takes between 0.8 and 3.2 secs - signer = rsa.generate(self.SIGNATURE_KEY_SIZE) - verifier = signer.get_verifying_key() - return verifier, signer - - def _encrypt_privkey(self, writekey, privkey): - enc = AES(writekey) - crypttext = enc.process(privkey) - return crypttext - - def _decrypt_privkey(self, enc_privkey): - enc = AES(self._writekey) - privkey = enc.process(enc_privkey) - return privkey - - def _populate(self, stuff): - # the Retrieval object calls this with values it discovers when - # downloading the slot. This is how a MutableFileNode that was - # created from a URI learns about its full key. - pass - - def _populate_pubkey(self, pubkey): - self._pubkey = pubkey - def _populate_required_shares(self, required_shares): - self._required_shares = required_shares - def _populate_total_shares(self, total_shares): - self._total_shares = total_shares - def _populate_seqnum(self, seqnum): - self._current_seqnum = seqnum - def _populate_root_hash(self, root_hash): - self._current_roothash = root_hash - - def _populate_privkey(self, privkey): - self._privkey = privkey - def _populate_encprivkey(self, encprivkey): - self._encprivkey = encprivkey - - - def get_write_enabler(self, peerid): - assert len(peerid) == 20 - return hashutil.ssk_write_enabler_hash(self._writekey, peerid) - def get_renewal_secret(self, peerid): - assert len(peerid) == 20 - crs = self._client.get_renewal_secret() - frs = hashutil.file_renewal_secret_hash(crs, self._storage_index) - return hashutil.bucket_renewal_secret_hash(frs, peerid) - def get_cancel_secret(self, peerid): - assert len(peerid) == 20 - ccs = self._client.get_cancel_secret() - fcs = hashutil.file_cancel_secret_hash(ccs, self._storage_index) - return hashutil.bucket_cancel_secret_hash(fcs, peerid) - - def get_writekey(self): - return self._writekey - def get_readkey(self): - return self._readkey - def get_storage_index(self): - return self._storage_index - def get_privkey(self): - return self._privkey - def get_encprivkey(self): - return self._encprivkey - def get_pubkey(self): - return self._pubkey - - def get_required_shares(self): - return self._required_shares - def get_total_shares(self): - return self._total_shares - - - def get_uri(self): - return self._uri.to_string() - def get_size(self): - return "?" # TODO: this is likely to cause problems, not being an int - def get_readonly(self): - if self.is_readonly(): - return self - ro = MutableFileNode(self._client) - ro.init_from_uri(self._uri.get_readonly()) - return ro - - def get_readonly_uri(self): - return self._uri.get_readonly().to_string() - - def is_mutable(self): - return self._uri.is_mutable() - def is_readonly(self): - return self._uri.is_readonly() - - def __hash__(self): - return hash((self.__class__, self._uri)) - def __cmp__(self, them): - if cmp(type(self), type(them)): - return cmp(type(self), type(them)) - if cmp(self.__class__, them.__class__): - return cmp(self.__class__, them.__class__) - return cmp(self._uri, them._uri) - - def get_verifier(self): - return IMutableFileURI(self._uri).get_verifier() - - def obtain_lock(self, res=None): - # stub, get real version from zooko's #265 patch - d = defer.Deferred() - d.callback(res) - return d - - def release_lock(self, res): - # stub - return res - - ############################ - - # methods exposed to the higher-layer application - - def update_servermap(self, old_map=None, mode=MODE_ENOUGH): - servermap = old_map or ServerMap() - d = self.obtain_lock() - d.addCallback(lambda res: - ServermapUpdater(self, servermap, mode).update()) - d.addBoth(self.release_lock) - return d - - def download_version(self, servermap, versionid): - """Returns a Deferred that fires with a string.""" - d = self.obtain_lock() - d.addCallback(lambda res: - Retrieve(self, servermap, versionid).download()) - d.addBoth(self.release_lock) - return d - - def publish(self, servermap, newdata): - assert self._pubkey, "update_servermap must be called before publish" - d = self.obtain_lock() - d.addCallback(lambda res: Publish(self, servermap).publish(newdata)) - # p = self.publish_class(self) - # self._client.notify_publish(p) - d.addBoth(self.release_lock) - return d - - def modify(self, modifier, *args, **kwargs): - """I use a modifier callback to apply a change to the mutable file. - I implement the following pseudocode:: - - obtain_mutable_filenode_lock() - while True: - update_servermap(MODE_WRITE) - old = retrieve_best_version() - new = modifier(old, *args, **kwargs) - if new == old: break - try: - publish(new) - except UncoordinatedWriteError: - continue - break - release_mutable_filenode_lock() - - The idea is that your modifier function can apply a delta of some - sort, and it will be re-run as necessary until it succeeds. The - modifier must inspect the old version to see whether its delta has - already been applied: if so it should return the contents unmodified. - """ - NotImplementedError - - ################################# - - def check(self): - verifier = self.get_verifier() - return self._client.getServiceNamed("checker").check(verifier) - - def download(self, target): - # fake it. TODO: make this cleaner. - d = self.download_to_data() - def _done(data): - target.open(len(data)) - target.write(data) - target.close() - return target.finish() - d.addCallback(_done) - return d - - def download_to_data(self): - d = self.obtain_lock() - d.addCallback(lambda res: self.update_servermap(mode=MODE_ENOUGH)) - def _updated(smap): - goal = smap.best_recoverable_version() - if not goal: - raise UnrecoverableFileError("no recoverable versions") - return self.download_version(smap, goal) - d.addCallback(_updated) - d.addBoth(self.release_lock) - return d - - def _publish(self, initial_contents): - p = Publish(self, None) - d = p.publish(initial_contents) - d.addCallback(lambda res: self) - return d - - def update(self, newdata): - d = self.obtain_lock() - d.addCallback(lambda res: self.update_servermap(mode=MODE_WRITE)) - d.addCallback(lambda smap: - Publish(self, smap).publish(newdata)) - d.addBoth(self.release_lock) - return d - - def overwrite(self, newdata): - return self.update(newdata) - - -class MutableWatcher(service.MultiService): - MAX_PUBLISH_STATUSES = 20 - MAX_RETRIEVE_STATUSES = 20 - name = "mutable-watcher" - - def __init__(self, stats_provider=None): - service.MultiService.__init__(self) - self.stats_provider = stats_provider - self._all_publish = weakref.WeakKeyDictionary() - self._recent_publish_status = [] - self._all_retrieve = weakref.WeakKeyDictionary() - self._recent_retrieve_status = [] - - def notify_publish(self, p): - self._all_publish[p] = None - self._recent_publish_status.append(p.get_status()) - if self.stats_provider: - self.stats_provider.count('mutable.files_published', 1) - #self.stats_provider.count('mutable.bytes_published', p._node.get_size()) - while len(self._recent_publish_status) > self.MAX_PUBLISH_STATUSES: - self._recent_publish_status.pop(0) - - def list_all_publish(self): - return self._all_publish.keys() - def list_active_publish(self): - return [p.get_status() for p in self._all_publish.keys() - if p.get_status().get_active()] - def list_recent_publish(self): - return self._recent_publish_status - - - def notify_retrieve(self, r): - self._all_retrieve[r] = None - self._recent_retrieve_status.append(r.get_status()) - if self.stats_provider: - self.stats_provider.count('mutable.files_retrieved', 1) - #self.stats_provider.count('mutable.bytes_retrieved', r._node.get_size()) - while len(self._recent_retrieve_status) > self.MAX_RETRIEVE_STATUSES: - self._recent_retrieve_status.pop(0) - - def list_all_retrieve(self): - return self._all_retrieve.keys() - def list_active_retrieve(self): - return [p.get_status() for p in self._all_retrieve.keys() - if p.get_status().get_active()] - def list_recent_retrieve(self): - return self._recent_retrieve_status - -class ResponseCache: - """I cache share data, to reduce the number of round trips used during - mutable file operations. All of the data in my cache is for a single - storage index, but I will keep information on multiple shares (and - multiple versions) for that storage index. - - My cache is indexed by a (verinfo, shnum) tuple. - - My cache entries contain a set of non-overlapping byteranges: (start, - data, timestamp) tuples. - """ - - def __init__(self): - self.cache = DictOfSets() - - def _does_overlap(self, x_start, x_length, y_start, y_length): - if x_start < y_start: - x_start, y_start = y_start, x_start - x_length, y_length = y_length, x_length - x_end = x_start + x_length - y_end = y_start + y_length - # this just returns a boolean. Eventually we'll want a form that - # returns a range. - if not x_length: - return False - if not y_length: - return False - if x_start >= y_end: - return False - if y_start >= x_end: - return False - return True - - - def _inside(self, x_start, x_length, y_start, y_length): - x_end = x_start + x_length - y_end = y_start + y_length - if x_start < y_start: - return False - if x_start >= y_end: - return False - if x_end < y_start: - return False - if x_end > y_end: - return False - return True - - def add(self, verinfo, shnum, offset, data, timestamp): - index = (verinfo, shnum) - self.cache.add(index, (offset, data, timestamp) ) - - def read(self, verinfo, shnum, offset, length): - """Try to satisfy a read request from cache. - Returns (data, timestamp), or (None, None) if the cache did not hold - the requested data. - """ - - # TODO: join multiple fragments, instead of only returning a hit if - # we have a fragment that contains the whole request - - index = (verinfo, shnum) - end = offset+length - for entry in self.cache.get(index, set()): - (e_start, e_data, e_timestamp) = entry - if self._inside(offset, length, e_start, len(e_data)): - want_start = offset - e_start - want_end = offset+length - e_start - return (e_data[want_start:want_end], e_timestamp) - return None, None - diff --git a/src/allmydata/test/test_mutable.py b/src/allmydata/test/test_mutable.py index 620f26e6..98e61cad 100644 --- a/src/allmydata/test/test_mutable.py +++ b/src/allmydata/test/test_mutable.py @@ -346,25 +346,27 @@ class MakeShares(unittest.TestCase): c = FakeClient() fn = FastMutableFileNode(c) CONTENTS = "some initial contents" - fn.create(CONTENTS) - p = mutable.Publish(fn) - r = mutable.Retrieve(fn) - # make some fake shares - shares_and_ids = ( ["%07d" % i for i in range(10)], range(10) ) - target_info = None - p._privkey = FakePrivKey(0) - p._encprivkey = "encprivkey" - p._pubkey = FakePubKey(0) - d = defer.maybeDeferred(p._generate_shares, - (shares_and_ids, - 3, 10, - 21, # segsize - len(CONTENTS), - target_info), - 3, # seqnum - "IV"*8) - def _done( (seqnum, root_hash, final_shares, target_info2) ): - self.failUnlessEqual(seqnum, 3) + d = fn.create(CONTENTS) + def _created(res): + p = Publish(fn, None) + self._p = p + p.newdata = CONTENTS + p.required_shares = 3 + p.total_shares = 10 + p.setup_encoding_parameters() + p._new_seqnum = 3 + p.salt = "SALT" * 4 + # make some fake shares + shares_and_ids = ( ["%07d" % i for i in range(10)], range(10) ) + p._privkey = fn.get_privkey() + p._encprivkey = fn.get_encprivkey() + p._pubkey = fn.get_pubkey() + return p._generate_shares(shares_and_ids) + d.addCallback(_created) + def _generated(res): + p = self._p + final_shares = p.shares + root_hash = p.root_hash self.failUnlessEqual(len(root_hash), 32) self.failUnless(isinstance(final_shares, dict)) self.failUnlessEqual(len(final_shares), 10)