download: refactor handling of URI Extension Block and crypttext hash tree, simplify things

Refactor into a class the logic of asking each server in turn until one of them gives an answer 
that validates.  It is called ValidatedThingObtainer.

Refactor the downloading and verification of the URI Extension Block into a class named 
ValidatedExtendedURIProxy.

The new logic of validating UEBs is minimalist: it doesn't require the UEB to contain any 
unncessary information, but of course it still accepts such information for backwards 
compatibility (so that this new download code is able to download files uploaded with old, and 
for that matter with current, upload code).

The new logic of validating UEBs follows the practice of doing all validation up front.  This 
practice advises one to isolate the validation of incoming data into one place, so that all of 
the rest of the code can assume only valid data.

If any redundant information is present in the UEB+URI, the new code cross-checks and asserts 
that it is all fully consistent.  This closes some issues where the uploader could have 
uploaded inconsistent redundant data, which would probably have caused the old downloader to 
simply reject that download after getting a Python exception, but perhaps could have caused 
greater harm to the old downloader.

I removed the notion of selecting an erasure codec from codec.py based on the string that was 
passed in the UEB.  Currently "crs" is the only such string that works, so 
"_assert(codec_name == 'crs')" is simpler and more explicit.  This is also in keeping with the 
"validate up front" strategy -- now if someone sets a different string than "crs" in their UEB, 
the downloader will reject the download in the "validate this UEB" function instead of in a 
separate "select the codec instance" function.

I removed the code to check plaintext hashes and plaintext Merkle Trees.  Uploaders do not 
produce this information any more (since it potentially exposes confidential information about 
the file), and the unit tests for it were disabled.  The downloader before this patch would 
check that plaintext hash or plaintext merkle tree if they were present, but not complain if 
they were absent.  The new downloader in this patch complains if they are present and doesn't 
check them.  (We might in the future re-introduce such hashes over the plaintext, but encrypt 
the hashes which are stored in the UEB to preserve confidentiality.  This would be a double-
check on the correctness of our own source code -- the current Merkle Tree over the ciphertext 
is already sufficient to guarantee the integrity of the download unless there is a bug in our 
Merkle Tree or AES implementation.) 

This patch increases the lines-of-code count by 8 (from 17,770 to 17,778), and reduces the 
uncovered-by-tests lines-of-code count by 24 (from 1408 to 1384).  Those numbers would be more 
meaningful if we omitted src/allmydata/util/ from the test-coverage statistics.
This commit is contained in:
Zooko O'Whielacronx 2008-12-05 08:17:54 -07:00
parent a0b5b5ab2b
commit b315619d6b
13 changed files with 518 additions and 463 deletions

View File

@ -7,59 +7,6 @@ from allmydata.util.assertutil import precondition
from allmydata.interfaces import ICodecEncoder, ICodecDecoder
import zfec
class ReplicatingEncoder(object):
implements(ICodecEncoder)
ENCODER_TYPE = "rep"
def set_params(self, data_size, required_shares, max_shares):
assert data_size % required_shares == 0
assert required_shares <= max_shares
self.data_size = data_size
self.required_shares = required_shares
self.max_shares = max_shares
def get_encoder_type(self):
return self.ENCODER_TYPE
def get_serialized_params(self):
return "%d" % self.required_shares
def get_block_size(self):
return self.data_size
def encode(self, inshares, desired_shareids=None):
assert isinstance(inshares, list)
for inshare in inshares:
assert isinstance(inshare, str)
assert self.required_shares * len(inshare) == self.data_size
data = "".join(inshares)
if desired_shareids is None:
desired_shareids = range(self.max_shares)
shares = [data for i in desired_shareids]
return defer.succeed((shares, desired_shareids))
class ReplicatingDecoder(object):
implements(ICodecDecoder)
def set_serialized_params(self, params):
self.required_shares = int(params)
def get_needed_shares(self):
return self.required_shares
def decode(self, some_shares, their_shareids):
assert len(some_shares) == self.required_shares
assert len(some_shares) == len(their_shareids)
data = some_shares[0]
chunksize = mathutil.div_ceil(len(data), self.required_shares)
numchunks = mathutil.div_ceil(len(data), chunksize)
l = [ data[i:i+chunksize] for i in range(0, len(data), chunksize) ]
return defer.succeed(l)
class CRSEncoder(object):
implements(ICodecEncoder)
ENCODER_TYPE = "crs"
@ -76,6 +23,9 @@ class CRSEncoder(object):
def get_encoder_type(self):
return self.ENCODER_TYPE
def get_params(self):
return (self.data_size, self.required_shares, self.max_shares)
def get_serialized_params(self):
return "%d-%d-%d" % (self.data_size, self.required_shares,
self.max_shares)
@ -98,11 +48,10 @@ class CRSEncoder(object):
class CRSDecoder(object):
implements(ICodecDecoder)
def set_serialized_params(self, params):
pieces = params.split("-")
self.data_size = int(pieces[0])
self.required_shares = int(pieces[1])
self.max_shares = int(pieces[2])
def set_params(self, data_size, required_shares, max_shares):
self.data_size = data_size
self.required_shares = required_shares
self.max_shares = max_shares
self.chunk_size = self.required_shares
self.num_chunks = mathutil.div_ceil(self.data_size, self.chunk_size)
@ -121,13 +70,6 @@ class CRSDecoder(object):
[int(s) for s in their_shareids])
return defer.succeed(data)
all_encoders = {
ReplicatingEncoder.ENCODER_TYPE: (ReplicatingEncoder, ReplicatingDecoder),
CRSEncoder.ENCODER_TYPE: (CRSEncoder, CRSDecoder),
}
def get_decoder_by_name(name):
decoder_class = all_encoders[name][1]
return decoder_class()
def parse_params(serializedparams):
pieces = serializedparams.split("-")
return int(pieces[0]), int(pieces[1]), int(pieces[2])

View File

@ -16,7 +16,7 @@ from allmydata.util import hashutil, mathutil, base32, log
from allmydata.util.hashutil import netstring
from allmydata.util.limiter import ConcurrencyLimiter
from allmydata.util.netstring import split_netstring
from allmydata.uri import NewDirectoryURI
from allmydata.uri import NewDirectoryURI, LiteralFileURI, from_string
from pycryptopp.cipher.aes import AES
class Deleter:
@ -202,6 +202,8 @@ class NewDirectoryNode:
assert isinstance(metadata, dict)
rwcap = child.get_uri() # might be RO if the child is not writeable
rocap = child.get_readonly_uri()
assert isinstance(rocap, str), rocap
assert isinstance(rwcap, str), rwcap
entry = "".join([netstring(name.encode("utf-8")),
netstring(rocap),
netstring(self._encrypt_rwcap(rwcap)),
@ -579,7 +581,8 @@ class DeepStats:
self.add("count-files")
size = node.get_size()
self.histogram("size-files-histogram", size)
if node.get_uri().startswith("URI:LIT:"):
theuri = from_string(node.get_uri())
if isinstance(theuri, LiteralFileURI):
self.add("count-literal-files")
self.add("size-literal-files", size)
else:

View File

@ -384,7 +384,7 @@ class IncompleteHashTree(CompleteBinaryTreeMixin, list):
for i in new_hashes:
if self[i]:
if self[i] != new_hashes[i]:
msg = "new hash does not match existing hash at "
msg = "new hash %s does not match existing hash %s at " % (base32.b2a(new_hashes[i]), base32.b2a(self[i]))
msg += self._name_hash(i)
raise BadHashError(msg)
else:

View File

@ -11,7 +11,9 @@ from twisted.python import log
from allmydata import storage
from allmydata.checker_results import CheckerResults
from allmydata.immutable import download
from allmydata.uri import CHKFileURI
from allmydata.util import hashutil
from allmydata.util.assertutil import _assert, precondition
class SimpleCHKFileChecker:
"""Return a list of (needed, total, found, sharemap), where sharemap maps
@ -68,7 +70,7 @@ class SimpleCHKFileChecker:
pass
def _done(self, res):
r = CheckerResults(self.uri, self.storage_index)
r = CheckerResults(self.uri.to_string(), self.storage_index)
report = []
healthy = bool(len(self.found_shares) >= self.total_shares)
r.set_healthy(healthy)
@ -129,7 +131,7 @@ class VerifyingOutput:
results.set_recoverable(False)
results.set_summary("Not Healthy")
def setup_hashtrees(self, plaintext_hashtree, crypttext_hashtree):
def got_crypttext_hash_tree(self, crypttext_hashtree):
self._crypttext_hash_tree = crypttext_hashtree
def write_segment(self, crypttext):
@ -162,10 +164,11 @@ class SimpleCHKFileVerifier(download.FileDownloader):
# remaining shareholders, and it cannot verify the plaintext.
check_plaintext_hash = False
def __init__(self, client, uri, storage_index, k, N, size, ueb_hash):
def __init__(self, client, u, storage_index, k, N, size, ueb_hash):
precondition(isinstance(u, CHKFileURI), u)
self._client = client
self._uri = uri
self._uri = u
self._storage_index = storage_index
self._uri_extension_hash = ueb_hash
self._total_shares = N
@ -175,7 +178,7 @@ class SimpleCHKFileVerifier(download.FileDownloader):
self._si_s = storage.si_b2a(self._storage_index)
self.init_logging()
self._check_results = r = CheckerResults(self._uri, self._storage_index)
self._check_results = r = CheckerResults(self._uri.to_string(), self._storage_index)
r.set_data({"count-shares-needed": k,
"count-shares-expected": N,
})
@ -226,9 +229,7 @@ class SimpleCHKFileVerifier(download.FileDownloader):
d.addCallback(self._got_all_shareholders)
# now get the uri_extension block from somebody and validate it
d.addCallback(self._obtain_uri_extension)
d.addCallback(self._got_uri_extension)
d.addCallback(self._get_hashtrees)
d.addCallback(self._create_validated_buckets)
d.addCallback(self._get_crypttext_hash_tree)
# once we know that, we can download blocks from everybody
d.addCallback(self._download_all_segments)
d.addCallback(self._done)

View File

@ -8,10 +8,10 @@ from foolscap import DeadReferenceError
from foolscap.eventual import eventually
from allmydata.util import base32, mathutil, hashutil, log, observer
from allmydata.util.assertutil import _assert
from allmydata.util.assertutil import _assert, precondition
from allmydata import codec, hashtree, storage, uri
from allmydata.interfaces import IDownloadTarget, IDownloader, IFileURI, \
IDownloadStatus, IDownloadResults, NotEnoughSharesError
from allmydata.interfaces import IDownloadTarget, IDownloader, IFileURI, IVerifierURI, \
IDownloadStatus, IDownloadResults, IValidatedThingProxy, NotEnoughSharesError
from allmydata.immutable import layout
from pycryptopp.cipher.aes import AES
@ -26,7 +26,7 @@ class BadURIExtensionHashValue(IntegrityCheckError):
pass
class BadURIExtension(IntegrityCheckError):
pass
class BadPlaintextHashValue(IntegrityCheckError):
class UnsupportedErasureCodec(BadURIExtension):
pass
class BadCrypttextHashValue(IntegrityCheckError):
pass
@ -50,11 +50,9 @@ class Output:
self.downloadable = downloadable
self._decryptor = AES(key)
self._crypttext_hasher = hashutil.crypttext_hasher()
self._plaintext_hasher = hashutil.plaintext_hasher()
self.length = 0
self.total_length = total_length
self._segment_number = 0
self._plaintext_hash_tree = None
self._crypttext_hash_tree = None
self._opened = False
self._log_parent = log_parent
@ -68,9 +66,8 @@ class Output:
kwargs["facility"] = "download.output"
return log.msg(*args, **kwargs)
def setup_hashtrees(self, plaintext_hashtree, crypttext_hashtree):
self._plaintext_hash_tree = plaintext_hashtree
self._crypttext_hash_tree = crypttext_hashtree
def got_crypttext_hash_tree(self, crypttext_hash_tree):
self._crypttext_hash_tree = crypttext_hash_tree
def write_segment(self, crypttext):
self.length += len(crypttext)
@ -94,18 +91,6 @@ class Output:
del crypttext
# now we're back down to 1*segment_size.
self._plaintext_hasher.update(plaintext)
if self._plaintext_hash_tree:
ph = hashutil.plaintext_segment_hasher()
ph.update(plaintext)
plaintext_leaves = {self._segment_number: ph.digest()}
self.log(format="plaintext leaf hash (%(bytes)sB) [%(segnum)d] is %(hash)s",
bytes=len(plaintext),
segnum=self._segment_number, hash=base32.b2a(ph.digest()),
level=log.NOISY)
self._plaintext_hash_tree.set_hashes(leaves=plaintext_leaves)
self._segment_number += 1
# We're still at 1*segment_size. The Downloadable is responsible for
# any memory usage beyond this.
@ -127,14 +112,230 @@ class Output:
def close(self):
self.crypttext_hash = self._crypttext_hasher.digest()
self.plaintext_hash = self._plaintext_hasher.digest()
self.log("download finished, closing IDownloadable", level=log.NOISY)
self.downloadable.close()
def finish(self):
return self.downloadable.finish()
class ValidatedBucket:
class ValidatedThingObtainer:
def __init__(self, validatedthingproxies, debugname, log_id):
self._validatedthingproxies = validatedthingproxies
self._debugname = debugname
self._log_id = log_id
def _bad(self, f, validatedthingproxy):
level = log.WEIRD
if f.check(DeadReferenceError):
level = log.UNUSUAL
log.msg(parent=self._log_id, facility="tahoe.immutable.download",
format="operation %(op)s from validatedthingproxy %(validatedthingproxy)s failed",
op=self._debugname, validatedthingproxy=str(validatedthingproxy),
failure=f, level=level, umid="JGXxBA")
if not self._validatedthingproxies:
raise NotEnoughSharesError("ran out of peers, last error was %s" % (f,))
# try again with a different one
return self._try_the_next_one()
def _try_the_next_one(self):
vtp = self._validatedthingproxies.pop(0)
d = vtp.start() # start() obtains, validates, and callsback-with the thing or else errbacks
d.addErrback(self._bad, vtp)
return d
def start(self):
return self._try_the_next_one()
class ValidatedCrypttextHashTreeProxy:
implements(IValidatedThingProxy)
""" I am a front-end for a remote crypttext hash tree using a local ReadBucketProxy -- I use
its get_crypttext_hashes() method and offer the Validated Thing protocol (i.e., I have a
start() method that fires with self once I get a valid one). """
def __init__(self, readbucketproxy, crypttext_hash_tree, fetch_failures=None):
# fetch_failures is for debugging -- see test_encode.py
self._readbucketproxy = readbucketproxy
self._fetch_failures = fetch_failures
self._crypttext_hash_tree = crypttext_hash_tree
def _validate(self, proposal):
ct_hashes = dict(list(enumerate(proposal)))
try:
self._crypttext_hash_tree.set_hashes(ct_hashes)
except hashtree.BadHashError:
if self._fetch_failures is not None:
self._fetch_failures["crypttext_hash_tree"] += 1
raise
return self
def start(self):
d = self._readbucketproxy.startIfNecessary()
d.addCallback(lambda ignored: self._readbucketproxy.get_crypttext_hashes())
d.addCallback(self._validate)
return d
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.num_segments = 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 = hashutil.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):
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.num_segments = mathutil.div_ceil(self._verifycap.size, self.segment_size)
tail_data_size = self._verifycap.size % self.segment_size
if not tail_data_size:
tail_data_size = self.segment_size
# padding for erasure code
self.tail_segment_size = mathutil.next_multiple(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) != hashutil.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.startIfNecessary()
d.addCallback(lambda ignored: self._readbucketproxy.get_uri_extension())
d.addCallback(self._check_integrity)
d.addCallback(self._parse_and_validate)
return d
class ValidatedReadBucketProxy:
"""I am a front-end for a remote storage bucket, responsible for
retrieving and validating data from that bucket.
@ -142,13 +343,14 @@ class ValidatedBucket:
"""
def __init__(self, sharenum, bucket,
share_hash_tree, roothash,
share_hash_tree, share_root_hash,
num_blocks):
""" share_root_hash is the root of the share hash tree; share_root_hash is stored in the UEB """
self.sharenum = sharenum
self.bucket = bucket
self._share_hash = None # None means not validated yet
self.share_hash_tree = share_hash_tree
self._roothash = roothash
self._share_root_hash = share_root_hash
self.block_hash_tree = hashtree.IncompleteHashTree(num_blocks)
self.started = False
@ -191,7 +393,7 @@ class ValidatedBucket:
try:
if not self._share_hash:
sh = dict(sharehashes)
sh[0] = self._roothash # always use our own root, from the URI
sh[0] = self._share_root_hash # always use our own root, from the URI
sht = self.share_hash_tree
if sht.get_leaf_index(self.sharenum) not in sh:
raise hashtree.NotEnoughHashesError
@ -231,7 +433,7 @@ class ValidatedBucket:
else:
log.msg(" block data start/end: %r .. %r" %
(blockdata[:50], blockdata[-50:]))
log.msg(" root hash: %s" % base32.b2a(self._roothash))
log.msg(" root hash: %s" % base32.b2a(self._share_root_hash))
log.msg(" share hash tree:\n" + self.share_hash_tree.dump())
log.msg(" block hash tree:\n" + self.block_hash_tree.dump())
lines = []
@ -426,19 +628,16 @@ class DownloadStatus:
class FileDownloader:
implements(IPushProducer)
check_crypttext_hash = True
check_plaintext_hash = True
_status = None
def __init__(self, client, u, downloadable):
precondition(isinstance(u, uri.CHKFileURI), u)
self._client = client
u = IFileURI(u)
self._uri = u
self._storage_index = u.storage_index
self._uri_extension_hash = u.uri_extension_hash
self._total_shares = u.total_shares
self._size = u.size
self._num_needed_shares = u.needed_shares
self._vup = None # ValidatedExtendedURIProxy
self._si_s = storage.si_b2a(self._storage_index)
self.init_logging()
@ -447,13 +646,13 @@ class FileDownloader:
self._status = s = DownloadStatus()
s.set_status("Starting")
s.set_storage_index(self._storage_index)
s.set_size(self._size)
s.set_size(self._uri.size)
s.set_helper(False)
s.set_active(True)
self._results = DownloadResults()
s.set_results(self._results)
self._results.file_size = self._size
self._results.file_size = self._uri.size
self._results.timings["servers_peer_selection"] = {}
self._results.timings["fetch_per_server"] = {}
self._results.timings["cumulative_fetch"] = 0.0
@ -466,22 +665,16 @@ class FileDownloader:
if IConsumer.providedBy(downloadable):
downloadable.registerProducer(self, True)
self._downloadable = downloadable
self._output = Output(downloadable, u.key, self._size, self._log_number,
self._output = Output(downloadable, u.key, self._uri.size, self._log_number,
self._status)
self.active_buckets = {} # k: shnum, v: bucket
self._share_buckets = [] # list of (sharenum, bucket) tuples
self._share_vbuckets = {} # k: shnum, v: set of ValidatedBuckets
self._uri_extension_sources = []
self._uri_extension_data = None
self._fetch_failures = {"uri_extension": 0, "crypttext_hash_tree": 0, }
self._fetch_failures = {"uri_extension": 0,
"plaintext_hashroot": 0,
"plaintext_hashtree": 0,
"crypttext_hashroot": 0,
"crypttext_hashtree": 0,
}
self._crypttext_hash_tree = None
def init_logging(self):
self._log_prefix = prefix = storage.si_b2a(self._storage_index)[:5]
@ -523,16 +716,15 @@ class FileDownloader:
self._status.set_active(False)
def start(self):
assert isinstance(self._uri, uri.CHKFileURI), (self._uri, type(self._uri))
self.log("starting download")
# first step: who should we download from?
d = defer.maybeDeferred(self._get_all_shareholders)
d.addCallback(self._got_all_shareholders)
# now get the uri_extension block from somebody and validate it
# now get the uri_extension block from somebody and integrity check it and parse and validate its contents
d.addCallback(self._obtain_uri_extension)
d.addCallback(self._got_uri_extension)
d.addCallback(self._get_hashtrees)
d.addCallback(self._create_validated_buckets)
d.addCallback(self._get_crypttext_hash_tree)
# once we know that, we can download blocks from everybody
d.addCallback(self._download_all_segments)
def _finished(res):
@ -582,7 +774,7 @@ class FileDownloader:
for sharenum, bucket in buckets.iteritems():
b = layout.ReadBucketProxy(bucket, peerid, self._si_s)
self.add_share_bucket(sharenum, b)
self._uri_extension_sources.append(b)
if self._results:
if peerid not in self._results.servermap:
self._results.servermap[peerid] = set()
@ -603,7 +795,7 @@ class FileDownloader:
shnum = vbucket.sharenum
del self.active_buckets[shnum]
s = self._share_vbuckets[shnum]
# s is a set of ValidatedBucket instances
# s is a set of ValidatedReadBucketProxy instances
s.remove(vbucket)
# ... which might now be empty
if not s:
@ -612,22 +804,21 @@ class FileDownloader:
del self._share_vbuckets[shnum]
def _got_all_shareholders(self, res):
assert isinstance(self._uri, uri.CHKFileURI), (self._uri, type(self._uri))
if self._results:
now = time.time()
self._results.timings["peer_selection"] = now - self._started
if len(self._share_buckets) < self._num_needed_shares:
if len(self._share_buckets) < self._uri.needed_shares:
raise NotEnoughSharesError
#for s in self._share_vbuckets.values():
# for vb in s:
# assert isinstance(vb, ValidatedBucket), \
# "vb is %s but should be a ValidatedBucket" % (vb,)
def _unpack_uri_extension_data(self, data):
return uri.unpack_extension(data)
# assert isinstance(vb, ValidatedReadBucketProxy), \
# "vb is %s but should be a ValidatedReadBucketProxy" % (vb,)
def _obtain_uri_extension(self, ignored):
assert isinstance(self._uri, uri.CHKFileURI), self._uri
# all shareholders are supposed to have a copy of uri_extension, and
# all are supposed to be identical. We compute the hash of the data
# that comes back, and compare it against the version in our URI. If
@ -635,171 +826,64 @@ class FileDownloader:
if self._status:
self._status.set_status("Obtaining URI Extension")
self._uri_extension_fetch_started = time.time()
def _validate(proposal, bucket):
h = hashutil.uri_extension_hash(proposal)
if h != self._uri_extension_hash:
self._fetch_failures["uri_extension"] += 1
msg = ("The copy of uri_extension we received from "
"%s was bad: wanted %s, got %s" %
(bucket,
base32.b2a(self._uri_extension_hash),
base32.b2a(h)))
self.log(msg, level=log.SCARY, umid="jnkTtQ")
raise BadURIExtensionHashValue(msg)
return self._unpack_uri_extension_data(proposal)
return self._obtain_validated_thing(None,
self._uri_extension_sources,
"uri_extension",
"get_uri_extension", (), _validate)
uri_extension_fetch_started = time.time()
def _obtain_validated_thing(self, ignored, sources, name, methname, args,
validatorfunc):
if not sources:
raise NotEnoughSharesError("started with zero peers while fetching "
"%s" % name)
bucket = sources[0]
sources = sources[1:]
#d = bucket.callRemote(methname, *args)
d = bucket.startIfNecessary()
d.addCallback(lambda res: getattr(bucket, methname)(*args))
d.addCallback(validatorfunc, bucket)
def _bad(f):
level = log.WEIRD
if f.check(DeadReferenceError):
level = log.UNUSUAL
self.log(format="operation %(op)s from vbucket %(vbucket)s failed",
op=name, vbucket=str(bucket),
failure=f, level=level, umid="JGXxBA")
if not sources:
raise NotEnoughSharesError("ran out of peers, last error was %s"
% (f,))
# try again with a different one
return self._obtain_validated_thing(None, sources, name,
methname, args, validatorfunc)
d.addErrback(_bad)
return d
def _got_uri_extension(self, uri_extension_data):
if self._results:
elapsed = time.time() - self._uri_extension_fetch_started
self._results.timings["uri_extension"] = elapsed
d = self._uri_extension_data = uri_extension_data
self._codec = codec.get_decoder_by_name(d['codec_name'])
self._codec.set_serialized_params(d['codec_params'])
self._tail_codec = codec.get_decoder_by_name(d['codec_name'])
self._tail_codec.set_serialized_params(d['tail_codec_params'])
crypttext_hash = d.get('crypttext_hash', None) # optional
if crypttext_hash:
assert isinstance(crypttext_hash, str)
assert len(crypttext_hash) == 32
self._crypttext_hash = crypttext_hash
self._plaintext_hash = d.get('plaintext_hash', None) # optional
self._roothash = d['share_root_hash']
self._segment_size = segment_size = d['segment_size']
self._total_segments = mathutil.div_ceil(self._size, segment_size)
self._current_segnum = 0
self._share_hashtree = hashtree.IncompleteHashTree(d['total_shares'])
self._share_hashtree.set_hashes({0: self._roothash})
def _get_hashtrees(self, res):
self._get_hashtrees_started = time.time()
if self._status:
self._status.set_status("Retrieving Hash Trees")
d = defer.maybeDeferred(self._get_plaintext_hashtrees)
d.addCallback(self._get_crypttext_hashtrees)
d.addCallback(self._setup_hashtrees)
return d
def _get_plaintext_hashtrees(self):
# plaintext hashes are optional. If the root isn't in the UEB, then
# the share will be holding an empty list. We don't even bother
# fetching it.
if "plaintext_root_hash" not in self._uri_extension_data:
self._plaintext_hashtree = None
return
def _validate_plaintext_hashtree(proposal, bucket):
if proposal[0] != self._uri_extension_data['plaintext_root_hash']:
self._fetch_failures["plaintext_hashroot"] += 1
msg = ("The copy of the plaintext_root_hash we received from"
" %s was bad" % bucket)
raise BadPlaintextHashValue(msg)
pt_hashtree = hashtree.IncompleteHashTree(self._total_segments)
pt_hashes = dict(list(enumerate(proposal)))
try:
pt_hashtree.set_hashes(pt_hashes)
except hashtree.BadHashError:
# the hashes they gave us were not self-consistent, even
# though the root matched what we saw in the uri_extension
# block
self._fetch_failures["plaintext_hashtree"] += 1
raise
self._plaintext_hashtree = pt_hashtree
d = self._obtain_validated_thing(None,
self._uri_extension_sources,
"plaintext_hashes",
"get_plaintext_hashes", (),
_validate_plaintext_hashtree)
return d
def _get_crypttext_hashtrees(self, res):
# 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.
if "crypttext_root_hash" not in self._uri_extension_data:
raise BadURIExtension("URI Extension block did not have the ciphertext hash tree root")
def _validate_crypttext_hashtree(proposal, bucket):
if proposal[0] != self._uri_extension_data['crypttext_root_hash']:
self._fetch_failures["crypttext_hashroot"] += 1
msg = ("The copy of the crypttext_root_hash we received from"
" %s was bad" % bucket)
raise BadCrypttextHashValue(msg)
ct_hashtree = hashtree.IncompleteHashTree(self._total_segments)
ct_hashes = dict(list(enumerate(proposal)))
try:
ct_hashtree.set_hashes(ct_hashes)
except hashtree.BadHashError:
self._fetch_failures["crypttext_hashtree"] += 1
raise
ct_hashtree.set_hashes(ct_hashes)
self._crypttext_hashtree = ct_hashtree
d = self._obtain_validated_thing(None,
self._uri_extension_sources,
"crypttext_hashes",
"get_crypttext_hashes", (),
_validate_crypttext_hashtree)
return d
def _setup_hashtrees(self, res):
self._output.setup_hashtrees(self._plaintext_hashtree,
self._crypttext_hashtree)
if self._results:
elapsed = time.time() - self._get_hashtrees_started
self._results.timings["hashtrees"] = elapsed
def _create_validated_buckets(self, ignored=None):
self._share_vbuckets = {}
vups = []
for sharenum, bucket in self._share_buckets:
vbucket = ValidatedBucket(sharenum, bucket,
self._share_hashtree,
self._roothash,
self._total_segments)
s = self._share_vbuckets.setdefault(sharenum, set())
s.add(vbucket)
vups.append(ValidatedExtendedURIProxy(bucket, self._uri.get_verifier(), self._fetch_failures))
vto = ValidatedThingObtainer(vups, debugname="vups", log_id=self._log_number)
d = vto.start()
def _got_uri_extension(vup):
precondition(isinstance(vup, ValidatedExtendedURIProxy), vup)
if self._results:
elapsed = time.time() - uri_extension_fetch_started
self._results.timings["uri_extension"] = elapsed
self._vup = vup
self._codec = codec.CRSDecoder()
self._codec.set_params(self._vup.segment_size, self._uri.needed_shares, self._uri.total_shares)
self._tail_codec = codec.CRSDecoder()
self._tail_codec.set_params(self._vup.tail_segment_size, self._uri.needed_shares, self._uri.total_shares)
self._current_segnum = 0
self._share_hashtree = hashtree.IncompleteHashTree(self._uri.total_shares)
self._share_hashtree.set_hashes({0: vup.share_root_hash})
self._crypttext_hash_tree = hashtree.IncompleteHashTree(self._vup.num_segments)
self._crypttext_hash_tree.set_hashes({0: self._vup.crypttext_root_hash})
d.addCallback(_got_uri_extension)
return d
def _get_crypttext_hash_tree(self, res):
vchtps = []
for sharenum, bucket in self._share_buckets:
vchtp = ValidatedCrypttextHashTreeProxy(bucket, self._crypttext_hash_tree, self._fetch_failures)
vchtps.append(vchtp)
_get_crypttext_hash_tree_started = time.time()
if self._status:
self._status.set_status("Retrieving crypttext hash tree")
vto = ValidatedThingObtainer(vchtps , debugname="vchtps", log_id=self._log_number)
d = vto.start()
def _got_crypttext_hash_tree(res):
self._crypttext_hash_tree = res._crypttext_hash_tree
self._output.got_crypttext_hash_tree(self._crypttext_hash_tree)
if self._results:
elapsed = time.time() - _get_crypttext_hash_tree_started
self._results.timings["hashtrees"] = elapsed
d.addCallback(_got_crypttext_hash_tree)
return d
def _activate_enough_buckets(self):
"""either return a mapping from shnum to a ValidatedBucket that can
"""either return a mapping from shnum to a ValidatedReadBucketProxy that can
provide data for that share, or raise NotEnoughSharesError"""
assert isinstance(self._uri, uri.CHKFileURI), self._uri
while len(self.active_buckets) < self._num_needed_shares:
while len(self.active_buckets) < self._uri.needed_shares:
# need some more
handled_shnums = set(self.active_buckets.keys())
available_shnums = set(self._share_vbuckets.keys())
@ -815,23 +899,31 @@ class FileDownloader:
def _download_all_segments(self, res):
# the promise: upon entry to this function, self._share_vbuckets
# contains enough buckets to complete the download, and some extra
# ones to tolerate some buckets dropping out or having errors.
# self._share_vbuckets is a dictionary that maps from shnum to a set
# of ValidatedBuckets, which themselves are wrappers around
# RIBucketReader references.
self.active_buckets = {} # k: shnum, v: ValidatedBucket instance
for sharenum, bucket in self._share_buckets:
vbucket = ValidatedReadBucketProxy(sharenum, bucket,
self._share_hashtree,
self._vup.share_root_hash,
self._vup.num_segments)
s = self._share_vbuckets.setdefault(sharenum, set())
s.add(vbucket)
# after the above code, self._share_vbuckets contains enough
# buckets to complete the download, and some extra ones to
# tolerate some buckets dropping out or having
# errors. self._share_vbuckets is a dictionary that maps from
# shnum to a set of ValidatedBuckets, which themselves are
# wrappers around RIBucketReader references.
self.active_buckets = {} # k: shnum, v: ValidatedReadBucketProxy instance
self._started_fetching = time.time()
d = defer.succeed(None)
for segnum in range(self._total_segments-1):
for segnum in range(self._vup.num_segments-1):
d.addCallback(self._download_segment, segnum)
# this pause, at the end of write, prevents pre-fetch from
# happening until the consumer is ready for more data.
d.addCallback(self._check_for_pause)
d.addCallback(self._download_tail_segment, self._total_segments-1)
d.addCallback(self._download_tail_segment, self._vup.num_segments-1)
return d
def _check_for_pause(self, res):
@ -844,15 +936,16 @@ class FileDownloader:
return res
def _download_segment(self, res, segnum):
assert isinstance(self._uri, uri.CHKFileURI), self._uri
if self._status:
self._status.set_status("Downloading segment %d of %d" %
(segnum+1, self._total_segments))
(segnum+1, self._vup.num_segments))
self.log("downloading seg#%d of %d (%d%%)"
% (segnum, self._total_segments,
100.0 * segnum / self._total_segments))
% (segnum, self._vup.num_segments,
100.0 * segnum / self._vup.num_segments))
# memory footprint: when the SegmentDownloader finishes pulling down
# all shares, we have 1*segment_size of usage.
segmentdler = SegmentDownloader(self, segnum, self._num_needed_shares,
segmentdler = SegmentDownloader(self, segnum, self._uri.needed_shares,
self._results)
started = time.time()
d = segmentdler.start()
@ -904,10 +997,11 @@ class FileDownloader:
return d
def _download_tail_segment(self, res, segnum):
assert isinstance(self._uri, uri.CHKFileURI), self._uri
self.log("downloading seg#%d of %d (%d%%)"
% (segnum, self._total_segments,
100.0 * segnum / self._total_segments))
segmentdler = SegmentDownloader(self, segnum, self._num_needed_shares,
% (segnum, self._vup.num_segments,
100.0 * segnum / self._vup.num_segments))
segmentdler = SegmentDownloader(self, segnum, self._uri.needed_shares,
self._results)
started = time.time()
d = segmentdler.start()
@ -940,8 +1034,8 @@ class FileDownloader:
del buffers
# we never send empty segments. If the data was an exact multiple
# of the segment size, the last segment will be full.
pad_size = mathutil.pad_size(self._size, self._segment_size)
tail_size = self._segment_size - pad_size
pad_size = mathutil.pad_size(self._uri.size, self._vup.segment_size)
tail_size = self._vup.segment_size - pad_size
segment = segment[:tail_size]
started_decrypt = time.time()
self._output.write_segment(segment)
@ -952,24 +1046,20 @@ class FileDownloader:
return d
def _done(self, res):
assert isinstance(self._uri, uri.CHKFileURI), self._uri
self.log("download done")
if self._results:
now = time.time()
self._results.timings["total"] = now - self._started
self._results.timings["segments"] = now - self._started_fetching
self._output.close()
if self.check_crypttext_hash and self._crypttext_hash:
_assert(self._crypttext_hash == self._output.crypttext_hash,
if self._vup.crypttext_hash:
_assert(self._vup.crypttext_hash == self._output.crypttext_hash,
"bad crypttext_hash: computed=%s, expected=%s" %
(base32.b2a(self._output.crypttext_hash),
base32.b2a(self._crypttext_hash)))
if self.check_plaintext_hash and self._plaintext_hash:
_assert(self._plaintext_hash == self._output.plaintext_hash,
"bad plaintext_hash: computed=%s, expected=%s" %
(base32.b2a(self._output.plaintext_hash),
base32.b2a(self._plaintext_hash)))
_assert(self._output.length == self._size,
got=self._output.length, expected=self._size)
base32.b2a(self._vup.crypttext_hash)))
_assert(self._output.length == self._uri.size,
got=self._output.length, expected=self._uri.size)
return self._output.finish()
def get_download_status(self):
@ -1043,12 +1133,6 @@ class ConsumerAdapter:
implements(IDownloadTarget, IConsumer)
def __init__(self, consumer):
self._consumer = consumer
self._when_finished = observer.OneShotObserverList()
def when_finished(self):
# I think this is unused, along with self._when_finished . But I need
# to trace the error paths to be sure.
return self._when_finished.when_fired()
def registerProducer(self, producer, streaming):
self._consumer.registerProducer(producer, streaming)
@ -1060,10 +1144,10 @@ class ConsumerAdapter:
def write(self, data):
self._consumer.write(data)
def close(self):
self._when_finished.fire(None)
pass
def fail(self, why):
self._when_finished.fire(why)
pass
def register_canceller(self, cb):
pass
def finish(self):

View File

@ -150,12 +150,12 @@ class Encoder(object):
# it. If the tail is short, we use a different codec instance. In
# addition, the tail codec must be fed data which has been padded out
# to the right size.
self.tail_size = self.file_size % self.segment_size
if not self.tail_size:
self.tail_size = self.segment_size
tail_size = self.file_size % self.segment_size
if not tail_size:
tail_size = self.segment_size
# the tail codec is responsible for encoding tail_size bytes
padded_tail_size = mathutil.next_multiple(self.tail_size,
padded_tail_size = mathutil.next_multiple(tail_size,
self.required_shares)
self._tail_codec = CRSEncoder()
self._tail_codec.set_params(padded_tail_size,

View File

@ -9,6 +9,7 @@ from foolscap.eventual import eventually
from allmydata.interfaces import IFileNode, IFileURI, ICheckable, \
IDownloadTarget
from allmydata.util import log, base32
from allmydata.uri import from_string as uri_from_string
from allmydata.immutable.checker import SimpleCHKFileChecker, \
SimpleCHKFileVerifier
from allmydata.immutable import download
@ -191,17 +192,18 @@ class FileNode(_ImmutableFileNodeBase):
# SimpleCHKFileVerifier, have it call monitor.raise_if_cancelled()
# before sending each request.
storage_index = self.u.storage_index
assert IFileURI.providedBy(self.u), self.u
k = self.u.needed_shares
N = self.u.total_shares
size = self.u.size
ueb_hash = self.u.uri_extension_hash
if verify:
v = self.verifier_class(self._client,
self.get_uri(), storage_index,
uri_from_string(self.get_uri()), storage_index,
k, N, size, ueb_hash)
else:
v = self.checker_class(self._client,
self.get_uri(), storage_index,
uri_from_string(self.get_uri()), storage_index,
k, N)
return v.start()

View File

@ -959,6 +959,9 @@ class ICodecEncoder(Interface):
may be invoked.
"""
def get_params():
"""Return the 3-tuple of data_size, required_shares, max_shares"""
def get_encoder_type():
"""Return a short string that describes the type of this encoder.
@ -967,23 +970,6 @@ class ICodecEncoder(Interface):
encoder class, and this encoder is an instance of that class.
"""
def get_serialized_params(): # TODO: maybe, maybe not
"""Return a string that describes the parameters of this encoder.
This string can be passed to the decoder to prepare it for handling
the encoded shares we create. It might contain more information than
was presented to set_params(), if there is some flexibility of
parameter choice.
This string is intended to be embedded in the URI, so there are
several restrictions on its contents. At the moment I'm thinking that
this means it may contain hex digits and hyphens, and nothing else.
The idea is that the URI contains something like '%s:%s:%s' %
(encoder.get_encoder_name(), encoder.get_serialized_params(),
b2a(crypttext_hash)), and this is enough information to construct a
compatible decoder.
"""
def get_block_size():
"""Return the length of the shares that encode() will produce.
"""
@ -1093,13 +1079,12 @@ class ICodecEncoder(Interface):
class ICodecDecoder(Interface):
def set_serialized_params(params):
"""Set up the parameters of this encoder, from a string returned by
encoder.get_serialized_params()."""
def set_params(data_size, required_shares, max_shares):
"""Set the params. They have to be exactly the same ones that were used for encoding. """
def get_needed_shares():
"""Return the number of shares needed to reconstruct the data.
set_serialized_params() is required to be called before this."""
set_params() is required to be called before this."""
def decode(some_shares, their_shareids):
"""Decode a partial list of shares into data.
@ -2159,6 +2144,10 @@ class RIKeyGenerator(RemoteInterface):
class FileTooLargeError(Exception):
pass
class IValidatedThingProxy(Interface):
def start():
""" Acquire a thing and validate it. Return a deferred which is eventually fired with
self if the thing is valid or errbacked if it can't be acquired or validated. """
class InsufficientVersionError(Exception):
def __init__(self, needed, got):

View File

@ -494,10 +494,9 @@ class Retrieve:
shares = shares[:k]
fec = codec.CRSDecoder()
params = "%d-%d-%d" % (segsize, k, N)
fec.set_serialized_params(params)
fec.set_params(segsize, k, N)
self.log("params %s, we have %d shares" % (params, len(shares)))
self.log("params %s, we have %d shares" % ((segsize, k, N), len(shares)))
self.log("about to decode, shareids=%s" % (shareids,))
d = defer.maybeDeferred(fec.decode, shares, shareids)
def _done(buffers):

View File

@ -2,17 +2,18 @@
import os
from twisted.trial import unittest
from twisted.python import log
from allmydata.codec import ReplicatingEncoder, ReplicatingDecoder, CRSEncoder, CRSDecoder
from allmydata.codec import CRSEncoder, CRSDecoder
import random
from allmydata.util import mathutil
class Tester:
class T(unittest.TestCase):
def do_test(self, size, required_shares, max_shares, fewer_shares=None):
data0s = [os.urandom(mathutil.div_ceil(size, required_shares)) for i in range(required_shares)]
enc = self.enc_class()
enc = CRSEncoder()
enc.set_params(size, required_shares, max_shares)
serialized_params = enc.get_serialized_params()
log.msg("serialized_params: %s" % serialized_params)
params = enc.get_params()
assert params == (size, required_shares, max_shares)
log.msg("params: %s" % (params,))
d = enc.encode(data0s)
def _done_encoding_all((shares, shareids)):
self.failUnlessEqual(len(shares), max_shares)
@ -28,8 +29,8 @@ class Tester:
d.addCallback(_check_fewer_shares)
def _decode((shares, shareids)):
dec = self.dec_class()
dec.set_serialized_params(serialized_params)
dec = CRSDecoder()
dec.set_params(*params)
d1 = dec.decode(shares, shareids)
return d1
@ -72,8 +73,8 @@ class Tester:
sharesl2 = random.sample(zip(self.shares, self.shareids), required_shares)
shares2 = [ x[0] for x in sharesl2 ]
shareids2 = [ x[1] for x in sharesl2 ]
dec = self.dec_class()
dec.set_serialized_params(serialized_params)
dec = CRSDecoder()
dec.set_params(*params)
d1 = dec.decode(shares1, shareids1)
d1.addCallback(_check_data)
d1.addCallback(lambda res: dec.decode(shares2, shareids2))
@ -91,12 +92,3 @@ class Tester:
def test_encode2(self):
return self.do_test(125, 25, 100, 90)
class Replicating(unittest.TestCase, Tester):
enc_class = ReplicatingEncoder
dec_class = ReplicatingDecoder
class CRS(unittest.TestCase, Tester):
enc_class = CRSEncoder
dec_class = CRSDecoder

View File

@ -1,4 +1,3 @@
from zope.interface import implements
from twisted.trial import unittest
from twisted.internet import defer, reactor
@ -7,7 +6,7 @@ from twisted.python.failure import Failure
from foolscap import eventual
from allmydata import hashtree, uri
from allmydata.immutable import encode, upload, download
from allmydata.util import hashutil
from allmydata.util import base32, hashutil
from allmydata.util.assertutil import _assert
from allmydata.interfaces import IStorageBucketWriter, IStorageBucketReader, NotEnoughSharesError
import common_util as testutil
@ -22,7 +21,7 @@ class FakeClient:
def log(self, *args, **kwargs):
pass
class FakeBucketWriterProxy:
class FakeBucketReaderWriterProxy:
implements(IStorageBucketWriter, IStorageBucketReader)
# these are used for both reading and writing
def __init__(self, mode="good"):
@ -111,10 +110,6 @@ class FakeBucketWriterProxy:
def get_plaintext_hashes(self):
def _try():
hashes = self.plaintext_hashes[:]
if self.mode == "bad plaintext hashroot":
hashes[0] = flip_bit(hashes[0])
if self.mode == "bad plaintext hash":
hashes[1] = flip_bit(hashes[1])
return hashes
return defer.maybeDeferred(_try)
@ -164,6 +159,102 @@ def make_data(length):
assert length <= len(data)
return data[:length]
class ValidatedExtendedURIProxy(unittest.TestCase):
K = 4
M = 10
SIZE = 200
SEGSIZE = 72
_TMP = SIZE%SEGSIZE
if _TMP == 0:
_TMP = SEGSIZE
if _TMP % K != 0:
_TMP += (K - (_TMP % K))
TAIL_SEGSIZE = _TMP
_TMP = SIZE / SEGSIZE
if SIZE % SEGSIZE != 0:
_TMP += 1
NUM_SEGMENTS = _TMP
mindict = { 'segment_size': SEGSIZE,
'crypttext_root_hash': '0'*hashutil.CRYPTO_VAL_SIZE,
'share_root_hash': '1'*hashutil.CRYPTO_VAL_SIZE }
optional_consistent = { 'crypttext_hash': '2'*hashutil.CRYPTO_VAL_SIZE,
'codec_name': "crs",
'codec_params': "%d-%d-%d" % (SEGSIZE, K, M),
'tail_codec_params': "%d-%d-%d" % (TAIL_SEGSIZE, K, M),
'num_segments': NUM_SEGMENTS,
'size': SIZE,
'needed_shares': K,
'total_shares': M,
'plaintext_hash': "anything",
'plaintext_root_hash': "anything", }
# optional_inconsistent = { 'crypttext_hash': ('2'*(hashutil.CRYPTO_VAL_SIZE-1), "", 77),
optional_inconsistent = { 'crypttext_hash': (77,),
'codec_name': ("digital fountain", ""),
'codec_params': ("%d-%d-%d" % (SEGSIZE, K-1, M),
"%d-%d-%d" % (SEGSIZE-1, K, M),
"%d-%d-%d" % (SEGSIZE, K, M-1)),
'tail_codec_params': ("%d-%d-%d" % (TAIL_SEGSIZE, K-1, M),
"%d-%d-%d" % (TAIL_SEGSIZE-1, K, M),
"%d-%d-%d" % (TAIL_SEGSIZE, K, M-1)),
'num_segments': (NUM_SEGMENTS-1,),
'size': (SIZE-1,),
'needed_shares': (K-1,),
'total_shares': (M-1,), }
def _test(self, uebdict):
uebstring = uri.pack_extension(uebdict)
uebhash = hashutil.uri_extension_hash(uebstring)
fb = FakeBucketReaderWriterProxy()
fb.put_uri_extension(uebstring)
verifycap = uri.CHKFileVerifierURI(storage_index='x'*16, uri_extension_hash=uebhash, needed_shares=self.K, total_shares=self.M, size=self.SIZE)
vup = download.ValidatedExtendedURIProxy(fb, verifycap)
return vup.start()
def _test_accept(self, uebdict):
return self._test(uebdict)
def _should_fail(self, res, expected_failures):
if isinstance(res, Failure):
res.trap(*expected_failures)
else:
self.fail("was supposed to raise %s, not get '%s'" % (expected_failures, res))
def _test_reject(self, uebdict):
d = self._test(uebdict)
d.addBoth(self._should_fail, (KeyError, download.BadURIExtension))
return d
def test_accept_minimal(self):
return self._test_accept(self.mindict)
def test_reject_insufficient(self):
dl = []
for k in self.mindict.iterkeys():
insuffdict = self.mindict.copy()
del insuffdict[k]
d = self._test_reject(insuffdict)
dl.append(d)
return defer.DeferredList(dl)
def test_accept_optional(self):
dl = []
for k in self.optional_consistent.iterkeys():
mydict = self.mindict.copy()
mydict[k] = self.optional_consistent[k]
d = self._test_accept(mydict)
dl.append(d)
return defer.DeferredList(dl)
def test_reject_optional(self):
dl = []
for k in self.optional_inconsistent.iterkeys():
for v in self.optional_inconsistent[k]:
mydict = self.mindict.copy()
mydict[k] = v
d = self._test_reject(mydict)
dl.append(d)
return defer.DeferredList(dl)
class Encode(unittest.TestCase):
def do_encode(self, max_segment_size, datalen, NUM_SHARES, NUM_SEGMENTS,
@ -192,7 +283,7 @@ class Encode(unittest.TestCase):
shareholders = {}
for shnum in range(NUM_SHARES):
peer = FakeBucketWriterProxy()
peer = FakeBucketReaderWriterProxy()
shareholders[shnum] = peer
all_shareholders.append(peer)
e.set_shareholders(shareholders)
@ -357,7 +448,7 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
all_peers = []
for shnum in range(NUM_SHARES):
mode = bucket_modes.get(shnum, "good")
peer = FakeBucketWriterProxy(mode)
peer = FakeBucketReaderWriterProxy(mode)
shareholders[shnum] = peer
e.set_shareholders(shareholders)
return e.start()
@ -385,12 +476,11 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
needed_shares=required_shares,
total_shares=num_shares,
size=file_size)
URI = u.to_string()
client = FakeClient()
if not target:
target = download.Data()
fd = download.FileDownloader(client, URI, target)
fd = download.FileDownloader(client, u, target)
# we manually cycle the FileDownloader through a number of steps that
# would normally be sequenced by a Deferred chain in
@ -405,9 +495,9 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
# Make it possible to obtain uri_extension from the shareholders.
# Arrange for shareholders[0] to be the first, so we can selectively
# corrupt the data it returns.
fd._uri_extension_sources = shareholders.values()
fd._uri_extension_sources.remove(shareholders[0])
fd._uri_extension_sources.insert(0, shareholders[0])
uri_extension_sources = shareholders.values()
uri_extension_sources.remove(shareholders[0])
uri_extension_sources.insert(0, shareholders[0])
d = defer.succeed(None)
@ -418,33 +508,22 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
# replace everybody's crypttext hash trees with a different one
# (computed over a different file), then modify our uri_extension
# to reflect the new crypttext hash tree root
def _corrupt_crypttext_hashes(uri_extension):
assert isinstance(uri_extension, dict)
assert 'crypttext_root_hash' in uri_extension
def _corrupt_crypttext_hashes(unused):
assert isinstance(fd._vup, download.ValidatedExtendedURIProxy), fd._vup
assert fd._vup.crypttext_root_hash, fd._vup
badhash = hashutil.tagged_hash("bogus", "data")
bad_crypttext_hashes = [badhash] * uri_extension['num_segments']
bad_crypttext_hashes = [badhash] * fd._vup.num_segments
badtree = hashtree.HashTree(bad_crypttext_hashes)
for bucket in shareholders.values():
bucket.crypttext_hashes = list(badtree)
uri_extension['crypttext_root_hash'] = badtree[0]
return uri_extension
fd._crypttext_hash_tree = hashtree.IncompleteHashTree(fd._vup.num_segments)
fd._crypttext_hash_tree.set_hashes({0: badtree[0]})
return fd._vup
d.addCallback(_corrupt_crypttext_hashes)
elif "omit_crypttext_root_hash" in recover_mode:
# make it as though the crypttext hash tree root had not
# been in the UEB
def _remove_crypttext_hashes(uri_extension):
assert isinstance(uri_extension, dict)
assert 'crypttext_root_hash' in uri_extension
del uri_extension['crypttext_root_hash']
return uri_extension
d.addCallback(_remove_crypttext_hashes)
d.addCallback(fd._got_uri_extension)
# also have the FileDownloader ask for hash trees
d.addCallback(fd._get_hashtrees)
d.addCallback(fd._get_crypttext_hash_tree)
d.addCallback(fd._create_validated_buckets)
d.addCallback(fd._download_all_segments)
d.addCallback(fd._done)
def _done(newdata):
@ -551,7 +630,7 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
d = self.send_and_recover((4,8,10), bucket_modes=modemap)
def _done(res):
self.failUnless(isinstance(res, Failure))
self.failUnless(res.check(NotEnoughSharesError))
self.failUnless(res.check(NotEnoughSharesError), res)
d.addBoth(_done)
return d
@ -566,10 +645,7 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
def assertFetchFailureIn(self, fd, where):
expected = {"uri_extension": 0,
"plaintext_hashroot": 0,
"plaintext_hashtree": 0,
"crypttext_hashroot": 0,
"crypttext_hashtree": 0,
"crypttext_hash_tree": 0,
}
if where is not None:
expected[where] += 1
@ -592,31 +668,13 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
d.addCallback(self.assertFetchFailureIn, "uri_extension")
return d
def OFF_test_bad_plaintext_hashroot(self):
# the first server has a bad plaintext hashroot, so we will fail over
# to a different server.
modemap = dict([(i, "bad plaintext hashroot") for i in range(1)] +
[(i, "good") for i in range(1, 10)])
d = self.send_and_recover((4,8,10), bucket_modes=modemap)
d.addCallback(self.assertFetchFailureIn, "plaintext_hashroot")
return d
def test_bad_crypttext_hashroot(self):
# the first server has a bad crypttext hashroot, so we will fail
# over to a different server.
modemap = dict([(i, "bad crypttext hashroot") for i in range(1)] +
[(i, "good") for i in range(1, 10)])
d = self.send_and_recover((4,8,10), bucket_modes=modemap)
d.addCallback(self.assertFetchFailureIn, "crypttext_hashroot")
return d
def OFF_test_bad_plaintext_hashes(self):
# the first server has a bad plaintext hash block, so we will fail
# over to a different server.
modemap = dict([(i, "bad plaintext hash") for i in range(1)] +
[(i, "good") for i in range(1, 10)])
d = self.send_and_recover((4,8,10), bucket_modes=modemap)
d.addCallback(self.assertFetchFailureIn, "plaintext_hashtree")
d.addCallback(self.assertFetchFailureIn, "crypttext_hash_tree")
return d
def test_bad_crypttext_hashes(self):
@ -625,7 +683,7 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
modemap = dict([(i, "bad crypttext hash") for i in range(1)] +
[(i, "good") for i in range(1, 10)])
d = self.send_and_recover((4,8,10), bucket_modes=modemap)
d.addCallback(self.assertFetchFailureIn, "crypttext_hashtree")
d.addCallback(self.assertFetchFailureIn, "crypttext_hash_tree")
return d
def test_bad_crypttext_hashes_failure(self):
@ -646,20 +704,6 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
d.addBoth(_done)
return d
def test_omitted_crypttext_hashes_failure(self):
# Test that the downloader requires a Merkle Tree over the
# ciphertext (per http://crisp.cs.du.edu/?q=node/88 -- the
# problem that checking the integrity of the shares could let
# more than one immutable file match the same read-cap).
modemap = dict([(i, "good") for i in range(0, 10)])
d = self.send_and_recover((4,8,10), bucket_modes=modemap,
recover_mode=("omit_crypttext_root_hash"))
def _done(res):
self.failUnless(isinstance(res, Failure))
self.failUnless(res.check(download.BadURIExtension), res)
d.addBoth(_done)
return d
def OFF_test_bad_plaintext(self):
# faking a decryption failure is easier: just corrupt the key
modemap = dict([(i, "good") for i in range(0, 10)])
@ -747,4 +791,3 @@ class Roundtrip(unittest.TestCase, testutil.ShouldFailMixin):
self.failUnless(res.check(NotEnoughSharesError))
d.addBoth(_done)
return d

View File

@ -130,9 +130,10 @@ class SystemTest(SystemTestMixin, unittest.TestCase):
return d1
d.addCallback(_do_upload)
def _upload_done(results):
uri = results.uri
log.msg("upload finished: uri is %s" % (uri,))
self.uri = uri
theuri = results.uri
log.msg("upload finished: uri is %s" % (theuri,))
self.uri = theuri
assert isinstance(self.uri, str), self.uri
dl = self.clients[1].getServiceNamed("downloader")
self.downloader = dl
d.addCallback(_upload_done)
@ -847,6 +848,7 @@ class SystemTest(SystemTestMixin, unittest.TestCase):
d1.addCallback(self.log, "publish finished")
def _stash_uri(filenode):
self.uri = filenode.get_uri()
assert isinstance(self.uri, str), (self.uri, filenode)
d1.addCallback(_stash_uri)
return d1
d.addCallback(_made_subdir1)
@ -2518,8 +2520,8 @@ class DeepCheckWebBad(DeepCheckBase, unittest.TestCase):
self.basedir = self.mktemp()
d = self.set_up_nodes()
d.addCallback(self.set_up_damaged_tree)
d.addCallback(self.do_test_check_bad)
d.addCallback(self.do_test_deepcheck_bad)
d.addCallback(self.do_check)
d.addCallback(self.do_deepcheck)
d.addCallback(self.do_test_web_bad)
d.addErrback(self.explain_web_error)
d.addErrback(self.explain_error)
@ -2620,8 +2622,8 @@ class DeepCheckWebBad(DeepCheckBase, unittest.TestCase):
def check_is_healthy(self, cr, where):
self.failUnless(ICheckerResults.providedBy(cr), where)
self.failUnless(cr.is_healthy(), where)
self.failUnless(ICheckerResults.providedBy(cr), (cr, type(cr), where))
self.failUnless(cr.is_healthy(), (cr.get_report(), cr.is_healthy(), cr.get_summary(), where))
self.failUnless(cr.is_recoverable(), where)
d = cr.get_data()
self.failUnlessEqual(d["count-recoverable-versions"], 1, where)
@ -2660,7 +2662,7 @@ class DeepCheckWebBad(DeepCheckBase, unittest.TestCase):
self.failUnlessEqual(d["count-unrecoverable-versions"], 1, where)
return cr
def do_test_check_bad(self, ignored):
def do_check(self, ignored):
d = defer.succeed(None)
# check the individual items, without verification. This will not
@ -2709,7 +2711,7 @@ class DeepCheckWebBad(DeepCheckBase, unittest.TestCase):
return d
def do_test_deepcheck_bad(self, ignored):
def do_deepcheck(self, ignored):
d = defer.succeed(None)
# now deep-check the root, with various verify= and repair= options

View File

@ -416,9 +416,7 @@ class DirectoryNodeHandler(RenderMixin, rend.Page, ReplaceMeMixin):
def abbreviated_dirnode(dirnode):
u = from_string_dirnode(dirnode.get_uri())
si = u.get_filenode_uri().storage_index
si_s = base32.b2a(si)
return si_s[:6]
return u.abbrev()
class DirectoryAsHTML(rend.Page):
# The remainder of this class is to render the directory into