tahoe-lafs/src/allmydata/mutable/servermap.py

1045 lines
44 KiB
Python

import sys, time
from zope.interface import implements
from itertools import count
from twisted.internet import defer
from twisted.python import failure
from foolscap.api import DeadReferenceError, RemoteException, eventually
from allmydata.util import base32, hashutil, idlib, log
from allmydata.util.dictutil import DictOfSets
from allmydata.storage.server import si_b2a
from allmydata.interfaces import IServermapUpdaterStatus
from pycryptopp.publickey import rsa
from allmydata.mutable.common import MODE_CHECK, MODE_ANYTHING, MODE_WRITE, MODE_READ, \
CorruptShareError, NeedMoreDataError
from allmydata.mutable.layout import unpack_prefix_and_signature, unpack_header, unpack_share, \
SIGNED_PREFIX_LENGTH
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.
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.
@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):
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
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, 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, 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 (s_peerid, shnum)
in self.servermap
if s_peerid == peerid])
def version_on_peer(self, peerid, shnum):
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 verinfo to tuples of
(num_distinct_shares, k, N) tuples."""
versionmap = self.make_versionmap()
all_shares = {}
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) = verinfo
all_shares[verinfo] = (len(s), k, N)
return all_shares
def highest_seqnum(self):
available = self.shares_available()
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,
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 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.
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.
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
class ServermapUpdater:
def __init__(self, filenode, storage_broker, monitor, servermap,
mode=MODE_READ, add_lease=False):
"""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?
# * 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 4000 bytes, which also happens to read enough actual data to
# pre-fetch an 18-entry dirnode.
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.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.
prefix = si_b2a(self._storage_index)[:5]
self._log_number = log.msg(format="SharemapUpdater(%(si)s): starting (%(mode)s)",
si=prefix, mode=mode)
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
# 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._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
sb = self._storage_broker
full_peerlist = sb.get_servers_for_index(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
k = self._node.get_required_shares()
if k is None:
# make a guess
k = 3
N = self._node.get_total_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)
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.all_peers():
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._status.set_status("Sending %d initial queries" % len(peerlist))
self._queries_outstanding = set()
self._sharemap = DictOfSets() # shnum -> [(peerid, seqnum, R)..]
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.
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):
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_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)
now = time.time()
elapsed = now - started
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", parent=lp,
level=log.NOISY)
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
for shnum,datav in datavs.items():
data = datav[0]
try:
verinfo = self._got_results_one_share(shnum, data, peerid, lp)
last_verinfo = verinfo
last_shnum = shnum
self._node._add_to_cache(verinfo, shnum, 0, data)
except CorruptShareError, e:
# log it and give the other shares a chance to be processed
f = failure.Failure()
self.log(format="bad share: %(f_value)s", f_value=str(f.value),
failure=f, parent=lp, level=log.WEIRD, umid="h5llHg")
self.notify_server_corruption(peerid, shnum, str(e))
self._bad_peers.add(peerid)
self._last_failure = f
checkstring = data[:SIGNED_PREFIX_LENGTH]
self._servermap.mark_bad_share(peerid, shnum, checkstring)
self._servermap.problems.append(f)
pass
self._status.timings["cumulative_verify"] += (time.time() - now)
if self._need_privkey and last_verinfo:
# send them a request for the privkey. We send one request per
# server.
lp2 = self.log("sending privkey request",
parent=lp, level=log.NOISY)
(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]
privkey_started = time.time()
d = self._do_read(ss, peerid, self._storage_index,
[last_shnum], readv)
d.addCallback(self._got_privkey_results, peerid, last_shnum,
privkey_started, lp2)
d.addErrback(self._privkey_query_failed, peerid, last_shnum, lp2)
d.addErrback(log.err)
d.addCallback(self._check_for_done)
d.addErrback(self._fatal_error)
# all done!
self.log("_got_results done", parent=lp, level=log.NOISY)
def notify_server_corruption(self, peerid, shnum, reason):
ss = self._servermap.connections[peerid]
ss.callRemoteOnly("advise_corrupt_share",
"mutable", self._storage_index, shnum, reason)
def _got_results_one_share(self, shnum, data, peerid, lp):
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)
# 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.get_pubkey():
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))
if self._need_privkey:
self._try_to_extract_privkey(data, peerid, shnum, lp)
(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.get_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),
parent=lp)
self._valid_versions.add(verinfo)
# We now know that this is a valid candidate verinfo.
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.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, lp):
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),
parent=lp)
# 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 NotEnoughSharesError(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(enc_privkey, peerid, shnum, lp)
def _try_to_validate_privkey(self, enc_privkey, peerid, shnum, lp):
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),
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)),
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):
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)
# 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, started, lp):
now = time.time()
elapsed = now - started
self._status.add_per_server_time(peerid, "privkey", started, elapsed)
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, umid="VA9uDQ")
return
datav = datavs[shnum]
enc_privkey = datav[0]
self._try_to_validate_privkey(enc_privkey, peerid, shnum, lp)
def _privkey_query_failed(self, f, peerid, shnum, lp):
self._queries_outstanding.discard(peerid)
if not self._running:
return
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,
)
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),
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",
parent=lp)
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("%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("done", parent=lp)
return self._done()
MAX_IN_FLIGHT = 5
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="%(completed)d completed, %(query)d to query: need more",
completed=self._queries_completed,
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("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]
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("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("no higher-seqnum: done", parent=lp)
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("no recoverable versions: need more", parent=lp,
level=log.NOISY)
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("found our boundary, %s" %
"".join(states),
parent=lp, level=log.NOISY)
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",
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",
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
# 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("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", parent=lp, level=log.NOISY)
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
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, umid="1cNvlw")
self._done_deferred.errback(f)