import sys, time
+from zope.interface import implements
+from itertools import count
from twisted.internet import defer
from twisted.python import failure
-from foolscap.eventual import eventually
-from allmydata.util import base32, hashutil, idlib, log
-from allmydata import storage
+from foolscap.api import DeadReferenceError, RemoteException, eventually, \
+ fireEventually
+from allmydata.util import base32, hashutil, idlib, log, deferredutil
+from allmydata.util.dictutil import DictOfSets
+from allmydata.storage.server import si_b2a
+from allmydata.interfaces import IServermapUpdaterStatus
from pycryptopp.publickey import rsa
-from common import MODE_CHECK, MODE_ANYTHING, MODE_WRITE, MODE_ENOUGH, \
- DictOfSets, CorruptShareError, NeedMoreDataError
-from layout import unpack_prefix_and_signature, unpack_header, unpack_share
+from allmydata.mutable.common import MODE_CHECK, MODE_ANYTHING, MODE_WRITE, MODE_READ, \
+ CorruptShareError
+from allmydata.mutable.layout import SIGNED_PREFIX_LENGTH, MDMFSlotReadProxy
+
+class UpdateStatus:
+ implements(IServermapUpdaterStatus)
+ statusid_counter = count(0)
+ def __init__(self):
+ self.timings = {}
+ self.timings["per_server"] = {}
+ self.timings["cumulative_verify"] = 0.0
+ self.privkey_from = None
+ self.problems = {}
+ self.active = True
+ self.storage_index = None
+ self.mode = "?"
+ self.status = "Not started"
+ self.progress = 0.0
+ self.counter = self.statusid_counter.next()
+ self.started = time.time()
+ self.finished = None
+
+ def add_per_server_time(self, peerid, op, sent, elapsed):
+ assert op in ("query", "late", "privkey")
+ if peerid not in self.timings["per_server"]:
+ self.timings["per_server"][peerid] = []
+ self.timings["per_server"][peerid].append((op,sent,elapsed))
+
+ def get_started(self):
+ return self.started
+ def get_finished(self):
+ return self.finished
+ def get_storage_index(self):
+ return self.storage_index
+ def get_mode(self):
+ return self.mode
+ def get_servermap(self):
+ return self.servermap
+ def get_privkey_from(self):
+ return self.privkey_from
+ def using_helper(self):
+ return False
+ def get_size(self):
+ return "-NA-"
+ 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_mode(self, mode):
+ self.mode = mode
+ def set_privkey_from(self, peerid):
+ self.privkey_from = peerid
+ def set_status(self, status):
+ self.status = status
+ def set_progress(self, value):
+ self.progress = value
+ def set_active(self, value):
+ self.active = value
+ def set_finished(self, when):
+ self.finished = when
class ServerMap:
"""I record the placement of mutable shares.
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.
+
+ @ivar servermap: a dictionary, mapping a (peerid, shnum) tuple to a
+ (versionid, timestamp) tuple. Each 'versionid' is a
+ tuple of (seqnum, root_hash, IV, segsize, datalength,
+ k, N, signed_prefix, offsets)
+
+ @ivar connections: maps peerid to a RemoteReference
+
+ @ivar bad_shares: dict with keys of (peerid, shnum) tuples, describing
+ shares that I should ignore (because a previous user of
+ the servermap determined that they were invalid). The
+ updater only locates a certain number of shares: if
+ some of these turn out to have integrity problems and
+ are unusable, the caller will need to mark those shares
+ as bad, then re-update the servermap, then try again.
+ The dict maps (peerid, shnum) tuple to old checkstring.
"""
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.servermap = {}
+ self.connections = {}
self.unreachable_peers = set() # peerids that didn't respond to queries
+ self.reachable_peers = set() # peerids that did respond to queries
self.problems = [] # mostly for debugging
+ self.bad_shares = {} # maps (peerid,shnum) to old checkstring
self.last_update_mode = None
self.last_update_time = 0
+ self.update_data = {} # (verinfo,shnum) => data
+
+ def copy(self):
+ s = ServerMap()
+ s.servermap = self.servermap.copy() # tuple->tuple
+ s.connections = self.connections.copy() # str->RemoteReference
+ s.unreachable_peers = set(self.unreachable_peers)
+ s.reachable_peers = set(self.reachable_peers)
+ s.problems = self.problems[:]
+ s.bad_shares = self.bad_shares.copy() # tuple->str
+ s.last_update_mode = self.last_update_mode
+ s.last_update_time = self.last_update_time
+ return s
+
+ def mark_bad_share(self, peerid, shnum, checkstring):
+ """This share was found to be bad, either in the checkstring or
+ signature (detected during mapupdate), or deeper in the share
+ (detected at retrieve time). Remove it from our list of useful
+ shares, and remember that it is bad so we don't add it back again
+ later. We record the share's old checkstring (which might be
+ corrupted or badly signed) so that a repair operation can do the
+ test-and-set using it as a reference.
+ """
+ key = (peerid, shnum) # record checkstring
+ self.bad_shares[key] = checkstring
+ self.servermap.pop(key, None)
+
+ def add_new_share(self, peerid, shnum, verinfo, timestamp):
+ """We've written a new share out, replacing any that was there
+ before."""
+ key = (peerid, shnum)
+ self.bad_shares.pop(key, None)
+ self.servermap[key] = (verinfo, timestamp)
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))
+
+ for ( (peerid, shnum), (verinfo, timestamp) ) in self.servermap.items():
+ (seqnum, root_hash, IV, segsize, datalength, k, N, prefix,
+ offsets_tuple) = verinfo
+ 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))
+ if self.problems:
+ print >>out, "%d PROBLEMS" % len(self.problems)
+ for f in self.problems:
+ print >>out, str(f)
return out
+ def all_peers(self):
+ return set([peerid
+ for (peerid, shnum)
+ in self.servermap])
+
+ def all_peers_for_version(self, verinfo):
+ """Return a set of peerids that hold shares for the given version."""
+ return set([peerid
+ for ( (peerid, shnum), (verinfo2, timestamp) )
+ in self.servermap.items()
+ if verinfo == verinfo2])
+
+ def make_sharemap(self):
+ """Return a dict that maps shnum to a set of peerds that hold it."""
+ sharemap = DictOfSets()
+ for (peerid, shnum) in self.servermap:
+ sharemap.add(shnum, peerid)
+ return sharemap
+
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))
+ for ( (peerid, shnum), (verinfo, timestamp) ) in self.servermap.items():
+ 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, [])])
+ for (s_peerid, shnum)
+ in self.servermap
+ if s_peerid == 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
+ key = (peerid, shnum)
+ if key in self.servermap:
+ (verinfo, timestamp) = self.servermap[key]
+ return verinfo
return None
def shares_available(self):
- """Return a dict that maps versionid to tuples of
- (num_distinct_shares, k) tuples."""
+ """Return a dict that maps verinfo to tuples of
+ (num_distinct_shares, k, N) tuples."""
versionmap = self.make_versionmap()
all_shares = {}
- for versionid, shares in versionmap.items():
+ for verinfo, 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)
+ offsets_tuple) = verinfo
+ all_shares[verinfo] = (len(s), k, N)
return all_shares
def highest_seqnum(self):
available = self.shares_available()
- seqnums = [versionid[0]
- for versionid in available.keys()]
+ seqnums = [verinfo[0]
+ for verinfo in available.keys()]
seqnums.append(0)
return max(seqnums)
+ def summarize_version(self, verinfo):
+ """Take a versionid, return a string that describes it."""
+ (seqnum, root_hash, IV, segsize, datalength, k, N, prefix,
+ offsets_tuple) = verinfo
+ return "seq%d-%s" % (seqnum, base32.b2a(root_hash)[:4])
+
+ def summarize_versions(self):
+ """Return a string describing which versions we know about."""
+ versionmap = self.make_versionmap()
+ bits = []
+ for (verinfo, shares) in versionmap.items():
+ vstr = self.summarize_version(verinfo)
+ shnums = set([shnum for (shnum, peerid, timestamp) in shares])
+ bits.append("%d*%s" % (len(shnums), vstr))
+ return "/".join(bits)
+
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,
return recoverable[-1]
return None
+ def size_of_version(self, verinfo):
+ """Given a versionid (perhaps returned by best_recoverable_version),
+ return the size of the file in bytes."""
+ (seqnum, root_hash, IV, segsize, datalength, k, N, prefix,
+ offsets_tuple) = verinfo
+ return datalength
+
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
+ versionmap = self.make_versionmap()
+ healths = {} # maps verinfo to (found,k)
+ unrecoverable = set()
+ highest_recoverable_seqnum = -1
+ 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])
+ healths[verinfo] = (len(shnums),k)
+ if len(shnums) < k:
+ unrecoverable.add(verinfo)
+ else:
+ highest_recoverable_seqnum = max(seqnum,
+ highest_recoverable_seqnum)
+
+ newversions = {}
+ for verinfo in unrecoverable:
+ (seqnum, root_hash, IV, segsize, datalength, k, N, prefix,
+ offsets_tuple) = verinfo
+ if seqnum > highest_recoverable_seqnum:
+ newversions[verinfo] = healths[verinfo]
+
+ return newversions
+
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
+ recoverable_seqnums = [verinfo[0]
+ for verinfo in self.recoverable_versions()]
+ for seqnum in recoverable_seqnums:
+ if recoverable_seqnums.count(seqnum) > 1:
+ return True
+ return False
+
+
+ def get_update_data_for_share_and_verinfo(self, shnum, verinfo):
+ """
+ I return the update data for the given shnum
+ """
+ update_data = self.update_data[shnum]
+ update_datum = [i[1] for i in update_data if i[0] == verinfo][0]
+ return update_datum
+
+
+ def set_update_data_for_share_and_verinfo(self, shnum, verinfo, data):
+ """
+ I record the block hash tree for the given shnum.
+ """
+ self.update_data.setdefault(shnum , []).append((verinfo, data))
+
class ServermapUpdater:
- def __init__(self, filenode, servermap, mode=MODE_ENOUGH):
+ def __init__(self, filenode, storage_broker, monitor, servermap,
+ mode=MODE_READ, add_lease=False, update_range=None):
+ """I update a servermap, locating a sufficient number of useful
+ shares and remembering where they are located.
+
+ """
+
self._node = filenode
+ self._storage_broker = storage_broker
+ self._monitor = monitor
self._servermap = servermap
self.mode = mode
+ self._add_lease = add_lease
self._running = True
self._storage_index = filenode.get_storage_index()
self._last_failure = None
+ self._status = UpdateStatus()
+ self._status.set_storage_index(self._storage_index)
+ self._status.set_progress(0.0)
+ self._status.set_mode(mode)
+
+ self._servers_responded = set()
+
# how much data should we read?
+ # SDMF:
# * 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]
# * 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
+ # MDMF:
+ # * Checkstring? [0:72]
+ # * If we want to validate the checkstring, then [0:72], [143:?] --
+ # the offset table will tell us for sure.
+ # * If we need the verification key, we have to consult the offset
+ # table as well.
+ # At this point, we don't know which we are. Our filenode can
+ # tell us, but it might be lying -- in some cases, we're
+ # responsible for telling it which kind of file it is.
+ self._read_size = 4000
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:
+
+ if mode == MODE_WRITE and not self._node.get_privkey():
self._need_privkey = True
+ # check+repair: repair requires the privkey, so if we didn't happen
+ # to ask for it during the check, we'll have problems doing the
+ # publish.
+
+ self.fetch_update_data = False
+ if mode == MODE_WRITE and update_range:
+ # We're updating the servermap in preparation for an
+ # in-place file update, so we need to fetch some additional
+ # data from each share that we find.
+ assert len(update_range) == 2
+
+ self.start_segment = update_range[0]
+ self.end_segment = update_range[1]
+ self.fetch_update_data = True
+
+ prefix = si_b2a(self._storage_index)[:5]
+ self._log_number = log.msg(format="SharemapUpdater(%(si)s): starting (%(mode)s)",
+ si=prefix, mode=mode)
- prefix = storage.si_b2a(self._storage_index)[:5]
- self._log_number = log.msg("SharemapUpdater(%s): starting" % prefix)
+ def get_status(self):
+ return self._status
def log(self, *args, **kwargs):
if "parent" not in kwargs:
kwargs["parent"] = self._log_number
+ if "facility" not in kwargs:
+ kwargs["facility"] = "tahoe.mutable.mapupdate"
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._started = time.time()
+ self._status.set_active(True)
# self._valid_versions is a set of validated verinfo tuples. We just
# use it to remember which versions had valid signatures, so we can
# 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
self._queries_completed = 0
- client = self._node._client
- full_peerlist = client.get_permuted_peers("storage",
- self._node._storage_index)
+ sb = self._storage_broker
+ # All of the peers, permuted by the storage index, as usual.
+ full_peerlist = [(s.get_serverid(), s.get_rref())
+ for s in sb.get_servers_for_psi(self._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
+ self._readers = {} # peerid -> dict(sharewriters), filled in
+ # after responses come in.
k = self._node.get_required_shares()
+ # For what cases can these conditions work?
if k is None:
# make a guess
k = 3
- N = self._node.get_required_shares()
+ N = self._node.get_total_shares()
if N is None:
N = 10
self.EPSILON = k
self.num_peers_to_query = k + self.EPSILON
if self.mode == MODE_CHECK:
+ # We want to query all of the peers.
initial_peers_to_query = dict(full_peerlist)
must_query = set(initial_peers_to_query.keys())
self.extra_peers = []
# 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.
+ # We don't query all of the peers because that could take a while.
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
# might also avoid the round trip required to read the encrypted
# private key.
- else:
+ else: # MODE_READ, MODE_ANYTHING
+ # 2k peers is good enough.
initial_peers_to_query, must_query = self._build_initial_querylist()
# this is a set of peers that we are required to get responses 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)
+ # I guess that self._must_query is a subset of
+ # initial_peers_to_query?
+ assert set(must_query).issubset(set(initial_peers_to_query))
self._send_initial_requests(initial_peers_to_query)
+ self._status.timings["initial_queries"] = time.time() - self._started
return self._done_deferred
def _build_initial_querylist(self):
initial_peers_to_query = {}
must_query = set()
- for peerid in self._servermap.servermap.keys():
+ for peerid in self._servermap.all_peers():
ss = self._servermap.connections[peerid]
# we send queries to everyone who was already in the sharemap
initial_peers_to_query[peerid] = ss
return initial_peers_to_query, must_query
def _send_initial_requests(self, peerlist):
+ self._status.set_status("Sending %d initial queries" % len(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)
+ if not peerlist:
+ # there is nobody to ask, so we need to short-circuit the state
+ # machine.
+ d = defer.maybeDeferred(self._check_for_done, None)
+ d.addErrback(self._fatal_error)
+
# 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.
# 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)
+ d.addCallback(self._check_for_done)
return d
def _do_read(self, ss, peerid, storage_index, shnums, readv):
+ if self._add_lease:
+ # send an add-lease message in parallel. The results are handled
+ # separately. This is sent before the slot_readv() so that we can
+ # be sure the add_lease is retired by the time slot_readv comes
+ # back (this relies upon our knowledge that the server code for
+ # add_lease is synchronous).
+ renew_secret = self._node.get_renewal_secret(peerid)
+ cancel_secret = self._node.get_cancel_secret(peerid)
+ d2 = ss.callRemote("add_lease", storage_index,
+ renew_secret, cancel_secret)
+ # we ignore success
+ d2.addErrback(self._add_lease_failed, peerid, storage_index)
d = ss.callRemote("slot_readv", storage_index, shnums, readv)
return d
+
+ def _got_corrupt_share(self, e, shnum, peerid, data, lp):
+ """
+ I am called when a remote server returns a corrupt share in
+ response to one of our queries. By corrupt, I mean a share
+ without a valid signature. I then record the failure, notify the
+ server of the corruption, and record the share as bad.
+ """
+ f = failure.Failure(e)
+ self.log(format="bad share: %(f_value)s", f_value=str(f),
+ failure=f, parent=lp, level=log.WEIRD, umid="h5llHg")
+ # Notify the server that its share is corrupt.
+ self.notify_server_corruption(peerid, shnum, str(e))
+ # By flagging this as a bad peer, we won't count any of
+ # the other shares on that peer as valid, though if we
+ # happen to find a valid version string amongst those
+ # shares, we'll keep track of it so that we don't need
+ # to validate the signature on those again.
+ self._bad_peers.add(peerid)
+ self._last_failure = f
+ # XXX: Use the reader for this?
+ checkstring = data[:SIGNED_PREFIX_LENGTH]
+ self._servermap.mark_bad_share(peerid, shnum, checkstring)
+ self._servermap.problems.append(f)
+
+
+ def _cache_good_sharedata(self, verinfo, shnum, now, data):
+ """
+ If one of my queries returns successfully (which means that we
+ were able to and successfully did validate the signature), I
+ cache the data that we initially fetched from the storage
+ server. This will help reduce the number of roundtrips that need
+ to occur when the file is downloaded, or when the file is
+ updated.
+ """
+ if verinfo:
+ self._node._add_to_cache(verinfo, shnum, 0, data)
+
+
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
+ peerid=idlib.shortnodeid_b2a(peerid),
+ numshares=len(datavs))
+ now = time.time()
+ elapsed = now - started
+ def _done_processing(ignored=None):
+ self._queries_outstanding.discard(peerid)
+ self._servermap.reachable_peers.add(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")
+ self.log("but we're not running, so we'll ignore it", parent=lp)
+ _done_processing()
+ self._status.add_per_server_time(peerid, "late", started, elapsed)
return
+ self._status.add_per_server_time(peerid, "query", started, elapsed)
if datavs:
self._good_peers.add(peerid)
else:
self._empty_peers.add(peerid)
- last_verinfo = None
- last_shnum = None
+ ss, storage_index = stuff
+ ds = []
+
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)
+ reader = MDMFSlotReadProxy(ss,
+ storage_index,
+ shnum,
+ data)
+ self._readers.setdefault(peerid, dict())[shnum] = reader
+ # our goal, with each response, is to validate the version
+ # information and share data as best we can at this point --
+ # we do this by validating the signature. To do this, we
+ # need to do the following:
+ # - If we don't already have the public key, fetch the
+ # public key. We use this to validate the signature.
+ if not self._node.get_pubkey():
+ # fetch and set the public key.
+ d = reader.get_verification_key()
+ d.addCallback(lambda results, shnum=shnum, peerid=peerid:
+ self._try_to_set_pubkey(results, peerid, shnum, lp))
+ # XXX: Make self._pubkey_query_failed?
+ d.addErrback(lambda error, shnum=shnum, peerid=peerid, data=data:
+ self._got_corrupt_share(error, shnum, peerid, data, lp))
+ else:
+ # we already have the public key.
+ d = defer.succeed(None)
+
+ # Neither of these two branches return anything of
+ # consequence, so the first entry in our deferredlist will
+ # be None.
+
+ # - Next, we need the version information. We almost
+ # certainly got this by reading the first thousand or so
+ # bytes of the share on the storage server, so we
+ # shouldn't need to fetch anything at this step.
+ d2 = reader.get_verinfo()
+ d2.addErrback(lambda error, shnum=shnum, peerid=peerid, data=data:
+ self._got_corrupt_share(error, shnum, peerid, data, lp))
+ # - Next, we need the signature. For an SDMF share, it is
+ # likely that we fetched this when doing our initial fetch
+ # to get the version information. In MDMF, this lives at
+ # the end of the share, so unless the file is quite small,
+ # we'll need to do a remote fetch to get it.
+ d3 = reader.get_signature()
+ d3.addErrback(lambda error, shnum=shnum, peerid=peerid, data=data:
+ self._got_corrupt_share(error, shnum, peerid, data, lp))
+ # Once we have all three of these responses, we can move on
+ # to validating the signature
+
+ # Does the node already have a privkey? If not, we'll try to
+ # fetch it here.
+ if self._need_privkey:
+ d4 = reader.get_encprivkey()
+ d4.addCallback(lambda results, shnum=shnum, peerid=peerid:
+ self._try_to_validate_privkey(results, peerid, shnum, lp))
+ d4.addErrback(lambda error, shnum=shnum, peerid=peerid, data=data:
+ self._privkey_query_failed(error, shnum, data, lp))
+ else:
+ d4 = defer.succeed(None)
+
+
+ if self.fetch_update_data:
+ # fetch the block hash tree and first + last segment, as
+ # configured earlier.
+ # Then set them in wherever we happen to want to set
+ # them.
+ ds = []
+ # XXX: We do this above, too. Is there a good way to
+ # make the two routines share the value without
+ # introducing more roundtrips?
+ ds.append(reader.get_verinfo())
+ ds.append(reader.get_blockhashes())
+ ds.append(reader.get_block_and_salt(self.start_segment))
+ ds.append(reader.get_block_and_salt(self.end_segment))
+ d5 = deferredutil.gatherResults(ds)
+ d5.addCallback(self._got_update_results_one_share, shnum)
+ else:
+ d5 = defer.succeed(None)
+
+ dl = defer.DeferredList([d, d2, d3, d4, d5])
+ dl.addBoth(self._turn_barrier)
+ dl.addCallback(lambda results, shnum=shnum, peerid=peerid:
+ self._got_signature_one_share(results, shnum, peerid, lp))
+ dl.addErrback(lambda error, shnum=shnum, data=data:
+ self._got_corrupt_share(error, shnum, peerid, data, lp))
+ dl.addCallback(lambda verinfo, shnum=shnum, peerid=peerid, data=data:
+ self._cache_good_sharedata(verinfo, shnum, now, data))
+ ds.append(dl)
+ # dl is a deferred list that will fire when all of the shares
+ # that we found on this peer are done processing. When dl fires,
+ # we know that processing is done, so we can decrement the
+ # semaphore-like thing that we incremented earlier.
+ dl = defer.DeferredList(ds, fireOnOneErrback=True)
+ # Are we done? Done means that there are no more queries to
+ # send, that there are no outstanding queries, and that we
+ # haven't received any queries that are still processing. If we
+ # are done, self._check_for_done will cause the done deferred
+ # that we returned to our caller to fire, which tells them that
+ # they have a complete servermap, and that we won't be touching
+ # the servermap anymore.
+ dl.addCallback(_done_processing)
+ dl.addCallback(self._check_for_done)
+ dl.addErrback(self._fatal_error)
+ # all done!
+ self.log("_got_results done", parent=lp, level=log.NOISY)
+ return dl
- 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 _turn_barrier(self, result):
+ """
+ I help the servermap updater avoid the recursion limit issues
+ discussed in #237.
+ """
+ return fireEventually(result)
+
+
+ def _try_to_set_pubkey(self, pubkey_s, peerid, shnum, lp):
+ if self._node.get_pubkey():
+ return # don't go through this again if we don't have to
+ fingerprint = hashutil.ssk_pubkey_fingerprint_hash(pubkey_s)
+ assert len(fingerprint) == 32
+ if fingerprint != self._node.get_fingerprint():
+ raise CorruptShareError(peerid, shnum,
+ "pubkey doesn't match fingerprint")
+ self._node._populate_pubkey(self._deserialize_pubkey(pubkey_s))
+ assert self._node.get_pubkey()
- 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)
+ def notify_server_corruption(self, peerid, shnum, reason):
+ ss = self._servermap.connections[peerid]
+ ss.callRemoteOnly("advise_corrupt_share",
+ "mutable", self._storage_index, shnum, reason)
- (ig_version, ig_seqnum, ig_root_hash, ig_IV, ig_k, ig_N,
- ig_segsize, ig_datalen, offsets) = unpack_header(data)
+
+ def _got_signature_one_share(self, results, shnum, peerid, lp):
+ # It is our job to give versioninfo to our caller. We need to
+ # raise CorruptShareError if the share is corrupt for any
+ # reason, something that our caller will handle.
+ self.log(format="_got_results: got shnum #%(shnum)d from peerid %(peerid)s",
+ shnum=shnum,
+ peerid=idlib.shortnodeid_b2a(peerid),
+ level=log.NOISY,
+ parent=lp)
+ if not self._running:
+ # We can't process the results, since we can't touch the
+ # servermap anymore.
+ self.log("but we're not running anymore.")
+ return None
+
+ _, verinfo, signature, __, ___ = results
+ (seqnum,
+ root_hash,
+ saltish,
+ segsize,
+ datalen,
+ k,
+ n,
+ prefix,
+ offsets) = verinfo[1]
offsets_tuple = tuple( [(key,value) for key,value in offsets.items()] )
- verinfo = (seqnum, root_hash, IV, segsize, datalength, k, N, prefix,
+ # XXX: This should be done for us in the method, so
+ # presumably you can go in there and fix it.
+ verinfo = (seqnum,
+ root_hash,
+ saltish,
+ segsize,
+ datalen,
+ k,
+ n,
+ prefix,
offsets_tuple)
+ # This tuple uniquely identifies a share on the grid; we use it
+ # to keep track of the ones that we've already seen.
if verinfo not in self._valid_versions:
- # it's a new pair. Verify the signature.
- valid = self._node._pubkey.verify(prefix, signature)
+ # This is a new version tuple, and we need to validate it
+ # against the public key before keeping track of it.
+ assert self._node.get_pubkey()
+ valid = self._node.get_pubkey().verify(prefix, signature[1])
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.
+ 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, datalen),
+ parent=lp)
+ self._valid_versions.add(verinfo)
+ # We now know that this is a valid candidate verinfo. Whether or
+ # not this instance of it is valid is a matter for the next
+ # statement; at this point, we just know that if we see this
+ # version info again, that its signature checks out and that
+ # we're okay to skip the signature-checking step.
+
+ # (peerid, shnum) are bound in the method invocation.
+ if (peerid, shnum) in self._servermap.bad_shares:
+ # we've been told that the rest of the data in this share is
+ # unusable, so don't add it to the servermap.
+ self.log("but we've been told this is a bad share",
+ parent=lp, level=log.UNUSUAL)
+ return verinfo
# Add the info to our servermap.
timestamp = time.time()
- self._servermap.servermap.add(peerid, (shnum, verinfo, timestamp))
+ self._servermap.add_new_share(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).
+ def _got_update_results_one_share(self, results, share):
+ """
+ I record the update results in results.
+ """
+ assert len(results) == 4
+ verinfo, blockhashes, start, end = results
+ (seqnum,
+ root_hash,
+ saltish,
+ segsize,
+ datalen,
+ k,
+ n,
+ prefix,
+ offsets) = verinfo
+ offsets_tuple = tuple( [(key,value) for key,value in offsets.items()] )
- return
+ # XXX: This should be done for us in the method, so
+ # presumably you can go in there and fix it.
+ verinfo = (seqnum,
+ root_hash,
+ saltish,
+ segsize,
+ datalen,
+ k,
+ n,
+ prefix,
+ offsets_tuple)
- (seqnum, root_hash, IV, k, N, segsize, datalen,
- pubkey, signature, share_hash_chain, block_hash_tree,
- share_data, enc_privkey) = r
+ update_data = (blockhashes, start, end)
+ self._servermap.set_update_data_for_share_and_verinfo(share,
+ verinfo,
+ update_data)
- return self._try_to_validate_privkey(self, enc_privkey, peerid, shnum)
- def _try_to_validate_privkey(self, enc_privkey, peerid, shnum):
+ def _deserialize_pubkey(self, pubkey_s):
+ verifier = rsa.create_verifying_key_from_string(pubkey_s)
+ return verifier
+
+ def _try_to_validate_privkey(self, enc_privkey, peerid, shnum, lp):
+ """
+ Given a writekey from a remote server, I validate it against the
+ writekey stored in my node. If it is valid, then I set the
+ privkey and encprivkey properties of the node.
+ """
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)
+ (idlib.nodeid_b2a(peerid)[:8], shnum),
+ parent=lp, level=log.WEIRD, umid="aJVccw")
return
# it's good
self.log("got valid privkey from shnum %d on peerid %s" %
- (shnum, idlib.shortnodeid_b2a(peerid)))
+ (shnum, idlib.shortnodeid_b2a(peerid)),
+ parent=lp)
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
+ self._status.set_privkey_from(peerid)
+
+ def _add_lease_failed(self, f, peerid, storage_index):
+ # Older versions of Tahoe didn't handle the add-lease message very
+ # well: <=1.1.0 throws a NameError because it doesn't implement
+ # remote_add_lease(), 1.2.0/1.3.0 throw IndexError on unknown buckets
+ # (which is most of them, since we send add-lease to everybody,
+ # before we know whether or not they have any shares for us), and
+ # 1.2.0 throws KeyError even on known buckets due to an internal bug
+ # in the latency-measuring code.
+
+ # we want to ignore the known-harmless errors and log the others. In
+ # particular we want to log any local errors caused by coding
+ # problems.
+
+ if f.check(DeadReferenceError):
+ return
+ if f.check(RemoteException):
+ if f.value.failure.check(KeyError, IndexError, NameError):
+ # this may ignore a bit too much, but that only hurts us
+ # during debugging
+ return
+ self.log(format="error in add_lease from [%(peerid)s]: %(f_value)s",
+ peerid=idlib.shortnodeid_b2a(peerid),
+ f_value=str(f.value),
+ failure=f,
+ level=log.WEIRD, umid="iqg3mw")
+ return
+ # local errors are cause for alarm
+ log.err(f,
+ format="local error in add_lease to [%(peerid)s]: %(f_value)s",
+ peerid=idlib.shortnodeid_b2a(peerid),
+ f_value=str(f.value),
+ level=log.WEIRD, umid="ZWh6HA")
def _query_failed(self, f, peerid):
- self.log("error during query: %s %s" % (f, f.value), level=log.WEIRD)
if not self._running:
return
+ level = log.WEIRD
+ if f.check(DeadReferenceError):
+ level = log.UNUSUAL
+ self.log(format="error during query: %(f_value)s",
+ f_value=str(f.value), failure=f,
+ level=level, umid="IHXuQg")
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?
+ # a peerid could be in both ServerMap.reachable_peers and
+ # .unreachable_peers if they responded to our query, but then an
+ # exception was raised in _got_results.
+ self._servermap.unreachable_peers.add(peerid)
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):
+ def _privkey_query_failed(self, f, peerid, shnum, lp):
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)
+ level = log.WEIRD
+ if f.check(DeadReferenceError):
+ level = log.UNUSUAL
+ self.log(format="error during privkey query: %(f_value)s",
+ f_value=str(f.value), failure=f,
+ parent=lp, level=level, umid="McoJ5w")
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
+ lp = 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, "
+ "need_privkey=%(need_privkey)s"
+ ),
+ mode=self.mode,
+ outstanding=len(self._queries_outstanding),
+ extra=len(self.extra_peers),
+ must=len(self._must_query),
+ need_privkey=self._need_privkey,
+ level=log.NOISY,
+ )
- 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 not self._running:
+ self.log("but we're not running", parent=lp, level=log.NOISY)
+ return
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))
+ self.log("%d 'must query' peers left" % len(self._must_query),
+ level=log.NOISY, parent=lp)
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")
+ self.log("all queries are retired, no extra peers: done",
+ parent=lp)
return self._done()
recoverable_versions = self._servermap.recoverable_versions()
if self.mode == MODE_ANYTHING:
if recoverable_versions:
- self.log("MODE_ANYTHING and %d recoverable versions: done"
- % len(recoverable_versions))
+ self.log("%d recoverable versions: done"
+ % len(recoverable_versions),
+ parent=lp)
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")
+ self.log("done", parent=lp)
return self._done()
MAX_IN_FLIGHT = 5
- if self.mode == MODE_ENOUGH:
+ if self.mode == MODE_READ:
# 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",
+ self.log(format="%(completed)d completed, %(query)d to query: need more",
completed=self._queries_completed,
- query=self.num_peers_to_query)
+ query=self.num_peers_to_query,
+ level=log.NOISY, parent=lp)
return self._send_more_queries(MAX_IN_FLIGHT)
if not recoverable_versions:
- self.log("ENOUGH, no recoverable versions: need more")
+ self.log("no recoverable versions: need more",
+ level=log.NOISY, parent=lp)
return self._send_more_queries(MAX_IN_FLIGHT)
highest_recoverable = max(recoverable_versions)
highest_recoverable_seqnum = highest_recoverable[0]
# 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")
+ self.log("evidence of higher seqnum: need more",
+ level=log.UNUSUAL, parent=lp)
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")
+ self.log("no higher-seqnum: done", parent=lp)
return self._done()
if self.mode == MODE_WRITE:
# every server in the world.
if not recoverable_versions:
- self.log("WRITE, no recoverable versions: need more")
+ self.log("no recoverable versions: need more", parent=lp,
+ level=log.NOISY)
return self._send_more_queries(MAX_IN_FLIGHT)
last_found = -1
if last_found != -1:
num_not_found += 1
if num_not_found >= self.EPSILON:
- self.log("MODE_WRITE: found our boundary, %s" %
- "".join(states))
+ self.log("found our boundary, %s" %
+ "".join(states),
+ parent=lp, level=log.NOISY)
found_boundary = True
break
# everybody to the left of here
if last_not_responded == -1:
# we're done
- self.log("have all our answers")
+ self.log("have all our answers",
+ parent=lp, level=log.NOISY)
# .. unless we're still waiting on the privkey
if self._need_privkey:
- self.log("but we're still waiting for the privkey")
+ self.log("but we're still waiting for the privkey",
+ parent=lp, level=log.NOISY)
# 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
# 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))
+ self.log("no boundary yet, %s" % "".join(states), parent=lp,
+ level=log.NOISY)
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")
+ self.log("catchall: need more", parent=lp, level=log.NOISY)
return self._send_more_queries(MAX_IN_FLIGHT)
def _send_more_queries(self, num_outstanding):
def _done(self):
if not self._running:
+ self.log("not running; we're already done")
return
self._running = False
+ now = time.time()
+ elapsed = now - self._started
+ self._status.set_finished(now)
+ self._status.timings["total"] = elapsed
+ self._status.set_progress(1.0)
+ self._status.set_status("Finished")
+ self._status.set_active(False)
+
self._servermap.last_update_mode = self.mode
self._servermap.last_update_time = self._started
# the servermap will not be touched after this
+ self.log("servermap: %s" % self._servermap.summarize_versions())
+
eventually(self._done_deferred.callback, self._servermap)
def _fatal_error(self, f):
- self.log("fatal error", failure=f, level=log.WEIRD)
+ self.log("fatal error", failure=f, level=log.WEIRD, umid="1cNvlw")
self._done_deferred.errback(f)
+