-from foolscap.api import DeadReferenceError, RemoteException
+from zope.interface import implements
from twisted.internet import defer
-from allmydata import hashtree
+from foolscap.api import DeadReferenceError, RemoteException
+from allmydata import hashtree, codec, uri
+from allmydata.interfaces import IValidatedThingProxy, IVerifierURI
+from allmydata.hashtree import IncompleteHashTree
from allmydata.check_results import CheckResults
-from allmydata.immutable import download
from allmydata.uri import CHKFileVerifierURI
from allmydata.util.assertutil import precondition
-from allmydata.util import base32, deferredutil, dictutil, log
+from allmydata.util import base32, deferredutil, dictutil, log, mathutil
from allmydata.util.hashutil import file_renewal_secret_hash, \
file_cancel_secret_hash, bucket_renewal_secret_hash, \
- bucket_cancel_secret_hash
+ bucket_cancel_secret_hash, uri_extension_hash, CRYPTO_VAL_SIZE, \
+ block_hash
from allmydata.immutable import layout
+class IntegrityCheckReject(Exception):
+ pass
+class BadURIExtension(IntegrityCheckReject):
+ pass
+class BadURIExtensionHashValue(IntegrityCheckReject):
+ pass
+class BadOrMissingHash(IntegrityCheckReject):
+ pass
+class UnsupportedErasureCodec(BadURIExtension):
+ pass
+
+class ValidatedExtendedURIProxy:
+ implements(IValidatedThingProxy)
+ """ I am a front-end for a remote UEB (using a local ReadBucketProxy),
+ responsible for retrieving and validating the elements from the UEB."""
+
+ def __init__(self, readbucketproxy, verifycap, fetch_failures=None):
+ # fetch_failures is for debugging -- see test_encode.py
+ self._fetch_failures = fetch_failures
+ self._readbucketproxy = readbucketproxy
+ precondition(IVerifierURI.providedBy(verifycap), verifycap)
+ self._verifycap = verifycap
+
+ # required
+ self.segment_size = None
+ self.crypttext_root_hash = None
+ self.share_root_hash = None
+
+ # computed
+ self.block_size = None
+ self.share_size = None
+ self.num_segments = None
+ self.tail_data_size = None
+ self.tail_segment_size = None
+
+ # optional
+ self.crypttext_hash = None
+
+ def __str__(self):
+ return "<%s %s>" % (self.__class__.__name__, self._verifycap.to_string())
+
+ def _check_integrity(self, data):
+ h = uri_extension_hash(data)
+ if h != self._verifycap.uri_extension_hash:
+ msg = ("The copy of uri_extension we received from %s was bad: wanted %s, got %s" %
+ (self._readbucketproxy,
+ base32.b2a(self._verifycap.uri_extension_hash),
+ base32.b2a(h)))
+ if self._fetch_failures is not None:
+ self._fetch_failures["uri_extension"] += 1
+ raise BadURIExtensionHashValue(msg)
+ else:
+ return data
+
+ def _parse_and_validate(self, data):
+ self.share_size = mathutil.div_ceil(self._verifycap.size,
+ self._verifycap.needed_shares)
+
+ d = uri.unpack_extension(data)
+
+ # There are several kinds of things that can be found in a UEB.
+ # First, things that we really need to learn from the UEB in order to
+ # do this download. Next: things which are optional but not redundant
+ # -- if they are present in the UEB they will get used. Next, things
+ # that are optional and redundant. These things are required to be
+ # consistent: they don't have to be in the UEB, but if they are in
+ # the UEB then they will be checked for consistency with the
+ # already-known facts, and if they are inconsistent then an exception
+ # will be raised. These things aren't actually used -- they are just
+ # tested for consistency and ignored. Finally: things which are
+ # deprecated -- they ought not be in the UEB at all, and if they are
+ # present then a warning will be logged but they are otherwise
+ # ignored.
+
+ # First, things that we really need to learn from the UEB:
+ # segment_size, crypttext_root_hash, and share_root_hash.
+ self.segment_size = d['segment_size']
+
+ self.block_size = mathutil.div_ceil(self.segment_size,
+ self._verifycap.needed_shares)
+ self.num_segments = mathutil.div_ceil(self._verifycap.size,
+ self.segment_size)
+
+ self.tail_data_size = self._verifycap.size % self.segment_size
+ if not self.tail_data_size:
+ self.tail_data_size = self.segment_size
+ # padding for erasure code
+ self.tail_segment_size = mathutil.next_multiple(self.tail_data_size,
+ self._verifycap.needed_shares)
+
+ # Ciphertext hash tree root is mandatory, so that there is at most
+ # one ciphertext that matches this read-cap or verify-cap. The
+ # integrity check on the shares is not sufficient to prevent the
+ # original encoder from creating some shares of file A and other
+ # shares of file B.
+ self.crypttext_root_hash = d['crypttext_root_hash']
+
+ self.share_root_hash = d['share_root_hash']
+
+
+ # Next: things that are optional and not redundant: crypttext_hash
+ if d.has_key('crypttext_hash'):
+ self.crypttext_hash = d['crypttext_hash']
+ if len(self.crypttext_hash) != CRYPTO_VAL_SIZE:
+ raise BadURIExtension('crypttext_hash is required to be hashutil.CRYPTO_VAL_SIZE bytes, not %s bytes' % (len(self.crypttext_hash),))
+
+
+ # Next: things that are optional, redundant, and required to be
+ # consistent: codec_name, codec_params, tail_codec_params,
+ # num_segments, size, needed_shares, total_shares
+ if d.has_key('codec_name'):
+ if d['codec_name'] != "crs":
+ raise UnsupportedErasureCodec(d['codec_name'])
+
+ if d.has_key('codec_params'):
+ ucpss, ucpns, ucpts = codec.parse_params(d['codec_params'])
+ if ucpss != self.segment_size:
+ raise BadURIExtension("inconsistent erasure code params: "
+ "ucpss: %s != self.segment_size: %s" %
+ (ucpss, self.segment_size))
+ if ucpns != self._verifycap.needed_shares:
+ raise BadURIExtension("inconsistent erasure code params: ucpns: %s != "
+ "self._verifycap.needed_shares: %s" %
+ (ucpns, self._verifycap.needed_shares))
+ if ucpts != self._verifycap.total_shares:
+ raise BadURIExtension("inconsistent erasure code params: ucpts: %s != "
+ "self._verifycap.total_shares: %s" %
+ (ucpts, self._verifycap.total_shares))
+
+ if d.has_key('tail_codec_params'):
+ utcpss, utcpns, utcpts = codec.parse_params(d['tail_codec_params'])
+ if utcpss != self.tail_segment_size:
+ raise BadURIExtension("inconsistent erasure code params: utcpss: %s != "
+ "self.tail_segment_size: %s, self._verifycap.size: %s, "
+ "self.segment_size: %s, self._verifycap.needed_shares: %s"
+ % (utcpss, self.tail_segment_size, self._verifycap.size,
+ self.segment_size, self._verifycap.needed_shares))
+ if utcpns != self._verifycap.needed_shares:
+ raise BadURIExtension("inconsistent erasure code params: utcpns: %s != "
+ "self._verifycap.needed_shares: %s" % (utcpns,
+ self._verifycap.needed_shares))
+ if utcpts != self._verifycap.total_shares:
+ raise BadURIExtension("inconsistent erasure code params: utcpts: %s != "
+ "self._verifycap.total_shares: %s" % (utcpts,
+ self._verifycap.total_shares))
+
+ if d.has_key('num_segments'):
+ if d['num_segments'] != self.num_segments:
+ raise BadURIExtension("inconsistent num_segments: size: %s, "
+ "segment_size: %s, computed_num_segments: %s, "
+ "ueb_num_segments: %s" % (self._verifycap.size,
+ self.segment_size,
+ self.num_segments, d['num_segments']))
+
+ if d.has_key('size'):
+ if d['size'] != self._verifycap.size:
+ raise BadURIExtension("inconsistent size: URI size: %s, UEB size: %s" %
+ (self._verifycap.size, d['size']))
+
+ if d.has_key('needed_shares'):
+ if d['needed_shares'] != self._verifycap.needed_shares:
+ raise BadURIExtension("inconsistent needed shares: URI needed shares: %s, UEB "
+ "needed shares: %s" % (self._verifycap.total_shares,
+ d['needed_shares']))
+
+ if d.has_key('total_shares'):
+ if d['total_shares'] != self._verifycap.total_shares:
+ raise BadURIExtension("inconsistent total shares: URI total shares: %s, UEB "
+ "total shares: %s" % (self._verifycap.total_shares,
+ d['total_shares']))
+
+ # Finally, things that are deprecated and ignored: plaintext_hash,
+ # plaintext_root_hash
+ if d.get('plaintext_hash'):
+ log.msg("Found plaintext_hash in UEB. This field is deprecated for security reasons "
+ "and is no longer used. Ignoring. %s" % (self,))
+ if d.get('plaintext_root_hash'):
+ log.msg("Found plaintext_root_hash in UEB. This field is deprecated for security "
+ "reasons and is no longer used. Ignoring. %s" % (self,))
+
+ return self
+
+ def start(self):
+ """Fetch the UEB from bucket, compare its hash to the hash from
+ verifycap, then parse it. Returns a deferred which is called back
+ with self once the fetch is successful, or is erred back if it
+ fails."""
+ d = self._readbucketproxy.get_uri_extension()
+ d.addCallback(self._check_integrity)
+ d.addCallback(self._parse_and_validate)
+ return d
+
+class ValidatedReadBucketProxy(log.PrefixingLogMixin):
+ """I am a front-end for a remote storage bucket, responsible for
+ retrieving and validating data from that bucket.
+
+ My get_block() method is used by BlockDownloaders.
+ """
+
+ def __init__(self, sharenum, bucket, share_hash_tree, num_blocks,
+ block_size, share_size):
+ """ share_hash_tree is required to have already been initialized with
+ the root hash (the number-0 hash), using the share_root_hash from the
+ UEB"""
+ precondition(share_hash_tree[0] is not None, share_hash_tree)
+ prefix = "%d-%s-%s" % (sharenum, bucket,
+ base32.b2a_l(share_hash_tree[0][:8], 60))
+ log.PrefixingLogMixin.__init__(self,
+ facility="tahoe.immutable.download",
+ prefix=prefix)
+ self.sharenum = sharenum
+ self.bucket = bucket
+ self.share_hash_tree = share_hash_tree
+ self.num_blocks = num_blocks
+ self.block_size = block_size
+ self.share_size = share_size
+ self.block_hash_tree = hashtree.IncompleteHashTree(self.num_blocks)
+
+ def get_all_sharehashes(self):
+ """Retrieve and validate all the share-hash-tree nodes that are
+ included in this share, regardless of whether we need them to
+ validate the share or not. Each share contains a minimal Merkle tree
+ chain, but there is lots of overlap, so usually we'll be using hashes
+ from other shares and not reading every single hash from this share.
+ The Verifier uses this function to read and validate every single
+ hash from this share.
+
+ Call this (and wait for the Deferred it returns to fire) before
+ calling get_block() for the first time: this lets us check that the
+ share share contains enough hashes to validate its own data, and
+ avoids downloading any share hash twice.
+
+ I return a Deferred which errbacks upon failure, probably with
+ BadOrMissingHash."""
+
+ d = self.bucket.get_share_hashes()
+ def _got_share_hashes(sh):
+ sharehashes = dict(sh)
+ try:
+ self.share_hash_tree.set_hashes(sharehashes)
+ except IndexError, le:
+ raise BadOrMissingHash(le)
+ except (hashtree.BadHashError, hashtree.NotEnoughHashesError), le:
+ raise BadOrMissingHash(le)
+ d.addCallback(_got_share_hashes)
+ return d
+
+ def get_all_blockhashes(self):
+ """Retrieve and validate all the block-hash-tree nodes that are
+ included in this share. Each share contains a full Merkle tree, but
+ we usually only fetch the minimal subset necessary for any particular
+ block. This function fetches everything at once. The Verifier uses
+ this function to validate the block hash tree.
+
+ Call this (and wait for the Deferred it returns to fire) after
+ calling get_all_sharehashes() and before calling get_block() for the
+ first time: this lets us check that the share contains all block
+ hashes and avoids downloading them multiple times.
+
+ I return a Deferred which errbacks upon failure, probably with
+ BadOrMissingHash.
+ """
+
+ # get_block_hashes(anything) currently always returns everything
+ needed = list(range(len(self.block_hash_tree)))
+ d = self.bucket.get_block_hashes(needed)
+ def _got_block_hashes(blockhashes):
+ if len(blockhashes) < len(self.block_hash_tree):
+ raise BadOrMissingHash()
+ bh = dict(enumerate(blockhashes))
+
+ try:
+ self.block_hash_tree.set_hashes(bh)
+ except IndexError, le:
+ raise BadOrMissingHash(le)
+ except (hashtree.BadHashError, hashtree.NotEnoughHashesError), le:
+ raise BadOrMissingHash(le)
+ d.addCallback(_got_block_hashes)
+ return d
+
+ def get_all_crypttext_hashes(self, crypttext_hash_tree):
+ """Retrieve and validate all the crypttext-hash-tree nodes that are
+ in this share. Normally we don't look at these at all: the download
+ process fetches them incrementally as needed to validate each segment
+ of ciphertext. But this is a convenient place to give the Verifier a
+ function to validate all of these at once.
+
+ Call this with a new hashtree object for each share, initialized with
+ the crypttext hash tree root. I return a Deferred which errbacks upon
+ failure, probably with BadOrMissingHash.
+ """
+
+ # get_crypttext_hashes() always returns everything
+ d = self.bucket.get_crypttext_hashes()
+ def _got_crypttext_hashes(hashes):
+ if len(hashes) < len(crypttext_hash_tree):
+ raise BadOrMissingHash()
+ ct_hashes = dict(enumerate(hashes))
+ try:
+ crypttext_hash_tree.set_hashes(ct_hashes)
+ except IndexError, le:
+ raise BadOrMissingHash(le)
+ except (hashtree.BadHashError, hashtree.NotEnoughHashesError), le:
+ raise BadOrMissingHash(le)
+ d.addCallback(_got_crypttext_hashes)
+ return d
+
+ def get_block(self, blocknum):
+ # the first time we use this bucket, we need to fetch enough elements
+ # of the share hash tree to validate it from our share hash up to the
+ # hashroot.
+ if self.share_hash_tree.needed_hashes(self.sharenum):
+ d1 = self.bucket.get_share_hashes()
+ else:
+ d1 = defer.succeed([])
+
+ # We might need to grab some elements of our block hash tree, to
+ # validate the requested block up to the share hash.
+ blockhashesneeded = self.block_hash_tree.needed_hashes(blocknum, include_leaf=True)
+ # We don't need the root of the block hash tree, as that comes in the
+ # share tree.
+ blockhashesneeded.discard(0)
+ d2 = self.bucket.get_block_hashes(blockhashesneeded)
+
+ if blocknum < self.num_blocks-1:
+ thisblocksize = self.block_size
+ else:
+ thisblocksize = self.share_size % self.block_size
+ if thisblocksize == 0:
+ thisblocksize = self.block_size
+ d3 = self.bucket.get_block_data(blocknum,
+ self.block_size, thisblocksize)
+
+ dl = deferredutil.gatherResults([d1, d2, d3])
+ dl.addCallback(self._got_data, blocknum)
+ return dl
+
+ def _got_data(self, results, blocknum):
+ precondition(blocknum < self.num_blocks,
+ self, blocknum, self.num_blocks)
+ sharehashes, blockhashes, blockdata = results
+ try:
+ sharehashes = dict(sharehashes)
+ except ValueError, le:
+ le.args = tuple(le.args + (sharehashes,))
+ raise
+ blockhashes = dict(enumerate(blockhashes))
+
+ candidate_share_hash = None # in case we log it in the except block below
+ blockhash = None # in case we log it in the except block below
+
+ try:
+ if self.share_hash_tree.needed_hashes(self.sharenum):
+ # This will raise exception if the values being passed do not
+ # match the root node of self.share_hash_tree.
+ try:
+ self.share_hash_tree.set_hashes(sharehashes)
+ except IndexError, le:
+ # Weird -- sharehashes contained index numbers outside of
+ # the range that fit into this hash tree.
+ raise BadOrMissingHash(le)
+
+ # To validate a block we need the root of the block hash tree,
+ # which is also one of the leafs of the share hash tree, and is
+ # called "the share hash".
+ if not self.block_hash_tree[0]: # empty -- no root node yet
+ # Get the share hash from the share hash tree.
+ share_hash = self.share_hash_tree.get_leaf(self.sharenum)
+ if not share_hash:
+ # No root node in block_hash_tree and also the share hash
+ # wasn't sent by the server.
+ raise hashtree.NotEnoughHashesError
+ self.block_hash_tree.set_hashes({0: share_hash})
+
+ if self.block_hash_tree.needed_hashes(blocknum):
+ self.block_hash_tree.set_hashes(blockhashes)
+
+ blockhash = block_hash(blockdata)
+ self.block_hash_tree.set_hashes(leaves={blocknum: blockhash})
+ #self.log("checking block_hash(shareid=%d, blocknum=%d) len=%d "
+ # "%r .. %r: %s" %
+ # (self.sharenum, blocknum, len(blockdata),
+ # blockdata[:50], blockdata[-50:], base32.b2a(blockhash)))
+
+ except (hashtree.BadHashError, hashtree.NotEnoughHashesError), le:
+ # log.WEIRD: indicates undetected disk/network error, or more
+ # likely a programming error
+ self.log("hash failure in block=%d, shnum=%d on %s" %
+ (blocknum, self.sharenum, self.bucket))
+ if self.block_hash_tree.needed_hashes(blocknum):
+ self.log(""" failure occurred when checking the block_hash_tree.
+ This suggests that either the block data was bad, or that the
+ block hashes we received along with it were bad.""")
+ else:
+ self.log(""" the failure probably occurred when checking the
+ share_hash_tree, which suggests that the share hashes we
+ received from the remote peer were bad.""")
+ self.log(" have candidate_share_hash: %s" % bool(candidate_share_hash))
+ self.log(" block length: %d" % len(blockdata))
+ self.log(" block hash: %s" % base32.b2a_or_none(blockhash))
+ if len(blockdata) < 100:
+ self.log(" block data: %r" % (blockdata,))
+ else:
+ self.log(" block data start/end: %r .. %r" %
+ (blockdata[:50], blockdata[-50:]))
+ self.log(" share hash tree:\n" + self.share_hash_tree.dump())
+ self.log(" block hash tree:\n" + self.block_hash_tree.dump())
+ lines = []
+ for i,h in sorted(sharehashes.items()):
+ lines.append("%3d: %s" % (i, base32.b2a_or_none(h)))
+ self.log(" sharehashes:\n" + "\n".join(lines) + "\n")
+ lines = []
+ for i,h in blockhashes.items():
+ lines.append("%3d: %s" % (i, base32.b2a_or_none(h)))
+ log.msg(" blockhashes:\n" + "\n".join(lines) + "\n")
+ raise BadOrMissingHash(le)
+
+ # If we made it here, the block is good. If the hash trees didn't
+ # like what they saw, they would have raised a BadHashError, causing
+ # our caller to see a Failure and thus ignore this block (as well as
+ # dropping this bucket).
+ return blockdata
+
+
class Checker(log.PrefixingLogMixin):
"""I query all servers to see if M uniquely-numbered shares are
available.
object that was passed into my constructor whether this task has been
cancelled (by invoking its raise_if_cancelled() method).
"""
- def __init__(self, client, verifycap, servers, verify, add_lease, monitor):
+ def __init__(self, verifycap, servers, verify, add_lease, secret_holder,
+ monitor):
assert precondition(isinstance(verifycap, CHKFileVerifierURI), verifycap, type(verifycap))
- assert precondition(isinstance(servers, (set, frozenset)), servers)
- for (serverid, serverrref) in servers:
- assert precondition(isinstance(serverid, str))
- prefix = "%s" % base32.b2a_l(verifycap.storage_index[:8], 60)
+ prefix = "%s" % base32.b2a_l(verifycap.get_storage_index()[:8], 60)
log.PrefixingLogMixin.__init__(self, facility="tahoe.immutable.checker", prefix=prefix)
- self._client = client
self._verifycap = verifycap
self._monitor = monitor
self._verify = verify # bool: verify what the servers claim, or not?
self._add_lease = add_lease
- self._share_hash_tree = None
-
- frs = file_renewal_secret_hash(client.get_renewal_secret(),
- self._verifycap.storage_index)
+ frs = file_renewal_secret_hash(secret_holder.get_renewal_secret(),
+ self._verifycap.get_storage_index())
self.file_renewal_secret = frs
- fcs = file_cancel_secret_hash(client.get_cancel_secret(),
- self._verifycap.storage_index)
+ fcs = file_cancel_secret_hash(secret_holder.get_cancel_secret(),
+ self._verifycap.get_storage_index())
self.file_cancel_secret = fcs
- def _get_renewal_secret(self, peerid):
- return bucket_renewal_secret_hash(self.file_renewal_secret, peerid)
- def _get_cancel_secret(self, peerid):
- return bucket_cancel_secret_hash(self.file_cancel_secret, peerid)
+ def _get_renewal_secret(self, seed):
+ return bucket_renewal_secret_hash(self.file_renewal_secret, seed)
+ def _get_cancel_secret(self, seed):
+ return bucket_cancel_secret_hash(self.file_cancel_secret, seed)
- def _get_buckets(self, server, storageindex, serverid):
+ def _get_buckets(self, s, storageindex):
"""Return a deferred that eventually fires with ({sharenum: bucket},
serverid, success). In case the server is disconnected or returns a
Failure then it fires with ({}, serverid, False) (A server
that we want to track and report whether or not each server
responded.)"""
- d = server.callRemote("get_buckets", storageindex)
+ rref = s.get_rref()
+ lease_seed = s.get_lease_seed()
if self._add_lease:
- renew_secret = self._get_renewal_secret(serverid)
- cancel_secret = self._get_cancel_secret(serverid)
- d2 = server.callRemote("add_lease", storageindex,
- renew_secret, cancel_secret)
- dl = defer.DeferredList([d, d2], consumeErrors=True)
- def _done(res):
- [(get_success, get_result),
- (addlease_success, addlease_result)] = res
- # ignore remote IndexError on the add_lease call. Propagate
- # local errors and remote non-IndexErrors
- if addlease_success:
- return get_result
- if not addlease_result.check(RemoteException):
- # Propagate local errors
- return addlease_result
- if addlease_result.value.failure.check(IndexError):
- # tahoe=1.3.0 raised IndexError on non-existant
- # buckets, which we ignore
- return get_result
- # propagate remote errors that aren't IndexError, including
- # the unfortunate internal KeyError bug that <1.3.0 had.
- return addlease_result
- dl.addCallback(_done)
- d = dl
+ renew_secret = self._get_renewal_secret(lease_seed)
+ cancel_secret = self._get_cancel_secret(lease_seed)
+ d2 = rref.callRemote("add_lease", storageindex,
+ renew_secret, cancel_secret)
+ d2.addErrback(self._add_lease_failed, s.get_name(), storageindex)
+ d = rref.callRemote("get_buckets", storageindex)
def _wrap_results(res):
- return (res, serverid, True)
+ return (res, True)
def _trap_errs(f):
level = log.WEIRD
if f.check(DeadReferenceError):
level = log.UNUSUAL
- self.log("failure from server on 'get_buckets' the REMOTE failure was:", facility="tahoe.immutable.checker", failure=f, level=level, umid="3uuBUQ")
- return ({}, serverid, False)
+ self.log("failure from server on 'get_buckets' the REMOTE failure was:",
+ facility="tahoe.immutable.checker",
+ failure=f, level=level, umid="AX7wZQ")
+ return ({}, False)
d.addCallbacks(_wrap_results, _trap_errs)
return d
- def _download_and_verify(self, serverid, sharenum, bucket):
+ def _add_lease_failed(self, f, server_name, 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 [%(name)s]: %(f_value)s",
+ name=server_name,
+ f_value=str(f.value),
+ failure=f,
+ level=log.WEIRD, umid="atbAxw")
+ return
+ # local errors are cause for alarm
+ log.err(f,
+ format="local error in add_lease to [%(name)s]: %(f_value)s",
+ name=server_name,
+ f_value=str(f.value),
+ level=log.WEIRD, umid="hEGuQg")
+
+
+ def _download_and_verify(self, server, sharenum, bucket):
"""Start an attempt to download and verify every block in this bucket
and return a deferred that will eventually fire once the attempt
completes.
it will not errback -- it will fire normally with the indicated
results."""
- b = layout.ReadBucketProxy(bucket, serverid, self._verifycap.storage_index)
- veup = download.ValidatedExtendedURIProxy(b, self._verifycap)
+ vcap = self._verifycap
+ b = layout.ReadBucketProxy(bucket, server, vcap.get_storage_index())
+ veup = ValidatedExtendedURIProxy(b, vcap)
d = veup.start()
+ def _got_ueb(vup):
+ share_hash_tree = IncompleteHashTree(vcap.total_shares)
+ share_hash_tree.set_hashes({0: vup.share_root_hash})
+
+ vrbp = ValidatedReadBucketProxy(sharenum, b,
+ share_hash_tree,
+ vup.num_segments,
+ vup.block_size,
+ vup.share_size)
+
+ # note: normal download doesn't use get_all_sharehashes(),
+ # because it gets more data than necessary. We've discussed the
+ # security properties of having verification and download look
+ # identical (so the server couldn't, say, provide good responses
+ # for one and not the other), but I think that full verification
+ # is more important than defending against inconsistent server
+ # behavior. Besides, they can't pass the verifier without storing
+ # all the data, so there's not so much to be gained by behaving
+ # inconsistently.
+ d = vrbp.get_all_sharehashes()
+ # we fill share_hash_tree before fetching any blocks, so the
+ # block fetches won't send redundant share-hash-tree requests, to
+ # speed things up. Then we fetch+validate all the blockhashes.
+ d.addCallback(lambda ign: vrbp.get_all_blockhashes())
+
+ cht = IncompleteHashTree(vup.num_segments)
+ cht.set_hashes({0: vup.crypttext_root_hash})
+ d.addCallback(lambda ign: vrbp.get_all_crypttext_hashes(cht))
+
+ d.addCallback(lambda ign: vrbp)
+ return d
+ d.addCallback(_got_ueb)
+
+ def _discard_result(r):
+ assert isinstance(r, str), r
+ # to free up the RAM
+ return None
+
+ def _get_blocks(vrbp):
+ def _get_block(ign, blocknum):
+ db = vrbp.get_block(blocknum)
+ db.addCallback(_discard_result)
+ return db
+
+ dbs = defer.succeed(None)
+ for blocknum in range(veup.num_segments):
+ dbs.addCallback(_get_block, blocknum)
+
+ # The Deferred we return will fire after every block of this
+ # share has been downloaded and verified successfully, or else it
+ # will errback as soon as the first error is observed.
+ return dbs
+
+ d.addCallback(_get_blocks)
+
+ # if none of those errbacked, the blocks (and the hashes above them)
+ # are good
+ def _all_good(ign):
+ return (True, sharenum, None)
+ d.addCallback(_all_good)
+
+ # but if anything fails, we'll land here
def _errb(f):
# We didn't succeed at fetching and verifying all the blocks of
# this share. Handle each reason for failure differently.
return (False, sharenum, 'incompatible')
elif f.check(layout.LayoutInvalid,
layout.RidiculouslyLargeURIExtensionBlock,
- download.BadOrMissingHash,
- download.BadURIExtensionHashValue):
+ BadOrMissingHash,
+ BadURIExtensionHashValue):
return (False, sharenum, 'corrupt')
# if it wasn't one of those reasons, re-raise the error
return f
-
- def _got_ueb(vup):
- self._share_hash_tree = hashtree.IncompleteHashTree(self._verifycap.total_shares)
- self._share_hash_tree.set_hashes({0: vup.share_root_hash})
-
- vrbp = download.ValidatedReadBucketProxy(sharenum, b, self._share_hash_tree, vup.num_segments, vup.block_size, vup.share_size)
-
- ds = []
- for blocknum in range(vup.num_segments):
- def _discard_result(r):
- assert isinstance(r, str), r
- # to free up the RAM
- return None
- d2 = vrbp.get_block(blocknum)
- d2.addCallback(_discard_result)
- ds.append(d2)
-
- dl = deferredutil.gatherResults(ds)
- # dl will fire once every block of this share has been downloaded
- # and verified, or else it will errback.
-
- def _cb(result):
- return (True, sharenum, None)
-
- dl.addCallback(_cb)
- return dl
-
- d.addCallback(_got_ueb)
d.addErrback(_errb)
return d
- def _verify_server_shares(self, serverid, ss):
+ def _verify_server_shares(self, s):
""" Return a deferred which eventually fires with a tuple of
- (set(sharenum), serverid, set(corruptsharenum),
+ (set(sharenum), server, set(corruptsharenum),
set(incompatiblesharenum), success) showing all the shares verified
to be served by this server, and all the corrupt shares served by the
server, and all the incompatible shares served by the server. In case
then disconnected and ceased responding, or returned a failure, it is
still marked with the True flag for 'success'.
"""
- d = self._get_buckets(ss, self._verifycap.storage_index, serverid)
+ d = self._get_buckets(s, self._verifycap.get_storage_index())
def _got_buckets(result):
- bucketdict, serverid, success = result
+ bucketdict, success = result
shareverds = []
for (sharenum, bucket) in bucketdict.items():
- d = self._download_and_verify(serverid, sharenum, bucket)
+ d = self._download_and_verify(s, sharenum, bucket)
shareverds.append(d)
dl = deferredutil.gatherResults(shareverds)
corrupt.add(sharenum)
elif whynot == 'incompatible':
incompatible.add(sharenum)
- return (verified, serverid, corrupt, incompatible, success)
+ return (verified, s, corrupt, incompatible, success)
dl.addCallback(collect)
return dl
def _err(f):
f.trap(RemoteException, DeadReferenceError)
- return (set(), serverid, set(), set(), False)
+ return (set(), s, set(), set(), False)
d.addCallbacks(_got_buckets, _err)
return d
- def _check_server_shares(self, serverid, ss):
+ def _check_server_shares(self, s):
"""Return a deferred which eventually fires with a tuple of
- (set(sharenum), serverid, set(), set(), responded) showing all the
+ (set(sharenum), server, set(), set(), responded) showing all the
shares claimed to be served by this server. In case the server is
- disconnected then it fires with (set() serverid, set(), set(), False)
+ disconnected then it fires with (set(), server, set(), set(), False)
(a server disconnecting when we ask it for buckets is the same, for
our purposes, as a server that says it has none, except that we want
to track and report whether or not each server responded.)"""
def _curry_empty_corrupted(res):
- buckets, serverid, responded = res
- return (set(buckets), serverid, set(), set(), responded)
- d = self._get_buckets(ss, self._verifycap.storage_index, serverid)
+ buckets, responded = res
+ return (set(buckets), s, set(), set(), responded)
+ d = self._get_buckets(s, self._verifycap.get_storage_index())
d.addCallback(_curry_empty_corrupted)
return d
def _format_results(self, results):
- cr = CheckResults(self._verifycap, self._verifycap.storage_index)
- d = {}
- d['count-shares-needed'] = self._verifycap.needed_shares
- d['count-shares-expected'] = self._verifycap.total_shares
-
- verifiedshares = dictutil.DictOfSets() # {sharenum: set(serverid)}
- servers = {} # {serverid: set(sharenums)}
- corruptsharelocators = [] # (serverid, storageindex, sharenum)
- incompatiblesharelocators = [] # (serverid, storageindex, sharenum)
-
- for theseverifiedshares, thisserverid, thesecorruptshares, theseincompatibleshares, thisresponded in results:
- servers.setdefault(thisserverid, set()).update(theseverifiedshares)
- for sharenum in theseverifiedshares:
- verifiedshares.setdefault(sharenum, set()).add(thisserverid)
- for sharenum in thesecorruptshares:
- corruptsharelocators.append((thisserverid, self._verifycap.storage_index, sharenum))
- for sharenum in theseincompatibleshares:
- incompatiblesharelocators.append((thisserverid, self._verifycap.storage_index, sharenum))
-
- d['count-shares-good'] = len(verifiedshares)
- d['count-good-share-hosts'] = len([s for s in servers.keys() if servers[s]])
+ SI = self._verifycap.get_storage_index()
+
+ verifiedshares = dictutil.DictOfSets() # {sharenum: set(server)}
+ servers = {} # {server: set(sharenums)}
+ corruptshare_locators = [] # (server, storageindex, sharenum)
+ incompatibleshare_locators = [] # (server, storageindex, sharenum)
+ servers_responding = set() # server
+
+ for verified, server, corrupt, incompatible, responded in results:
+ servers.setdefault(server, set()).update(verified)
+ for sharenum in verified:
+ verifiedshares.setdefault(sharenum, set()).add(server)
+ for sharenum in corrupt:
+ corruptshare_locators.append((server, SI, sharenum))
+ for sharenum in incompatible:
+ incompatibleshare_locators.append((server, SI, sharenum))
+ if responded:
+ servers_responding.add(server)
+
+ good_share_hosts = len([s for s in servers.keys() if servers[s]])
assert len(verifiedshares) <= self._verifycap.total_shares, (verifiedshares.keys(), self._verifycap.total_shares)
if len(verifiedshares) == self._verifycap.total_shares:
- cr.set_healthy(True)
- cr.set_summary("Healthy")
+ healthy = True
+ summary = "Healthy"
else:
- cr.set_healthy(False)
- cr.set_summary("Not Healthy: %d shares (enc %d-of-%d)" %
- (len(verifiedshares),
- self._verifycap.needed_shares,
- self._verifycap.total_shares))
+ healthy = False
+ summary = ("Not Healthy: %d shares (enc %d-of-%d)" %
+ (len(verifiedshares),
+ self._verifycap.needed_shares,
+ self._verifycap.total_shares))
if len(verifiedshares) >= self._verifycap.needed_shares:
- cr.set_recoverable(True)
- d['count-recoverable-versions'] = 1
- d['count-unrecoverable-versions'] = 0
+ recoverable = 1
+ unrecoverable = 0
else:
- cr.set_recoverable(False)
- d['count-recoverable-versions'] = 0
- d['count-unrecoverable-versions'] = 1
-
- d['servers-responding'] = list(servers)
- d['sharemap'] = verifiedshares
- # no such thing as wrong shares of an immutable file
- d['count-wrong-shares'] = 0
- d['list-corrupt-shares'] = corruptsharelocators
- d['count-corrupt-shares'] = len(corruptsharelocators)
- d['list-incompatible-shares'] = incompatiblesharelocators
- d['count-incompatible-shares'] = len(incompatiblesharelocators)
-
+ recoverable = 0
+ unrecoverable = 1
# The file needs rebalancing if the set of servers that have at least
# one share is less than the number of uniquely-numbered shares
# available.
- cr.set_needs_rebalancing(d['count-good-share-hosts'] < d['count-shares-good'])
-
- cr.set_data(d)
+ # TODO: this may be wrong, see ticket #1115 comment:27 and ticket #1784.
+ needs_rebalancing = bool(good_share_hosts < len(verifiedshares))
+
+ cr = CheckResults(self._verifycap, SI,
+ healthy=healthy, recoverable=bool(recoverable),
+ needs_rebalancing=needs_rebalancing,
+ count_shares_needed=self._verifycap.needed_shares,
+ count_shares_expected=self._verifycap.total_shares,
+ count_shares_good=len(verifiedshares),
+ count_good_share_hosts=good_share_hosts,
+ count_recoverable_versions=recoverable,
+ count_unrecoverable_versions=unrecoverable,
+ servers_responding=list(servers_responding),
+ sharemap=verifiedshares,
+ count_wrong_shares=0, # no such thing, for immutable
+ list_corrupt_shares=corruptshare_locators,
+ count_corrupt_shares=len(corruptshare_locators),
+ list_incompatible_shares=incompatibleshare_locators,
+ count_incompatible_shares=len(incompatibleshare_locators),
+ summary=summary,
+ report=[],
+ share_problems=[],
+ servermap=None)
return cr
def start(self):
ds = []
if self._verify:
- for (serverid, ss) in self._servers:
- ds.append(self._verify_server_shares(serverid, ss))
+ for s in self._servers:
+ ds.append(self._verify_server_shares(s))
else:
- for (serverid, ss) in self._servers:
- ds.append(self._check_server_shares(serverid, ss))
+ for s in self._servers:
+ ds.append(self._check_server_shares(s))
return deferredutil.gatherResults(ds).addCallback(self._format_results)
projects / tahoe-lafs / tahoe-lafs.git / blobdiff