Tor 0.2.3.11-alpha marks feature-freeze for the 0.2.3 tree. It deploys
the last step of the plan to limit maximum circuit length, includes
a wide variety of hidden service performance and correctness fixes,
works around an OpenSSL security flaw if your distro is too stubborn
to upgrade, and fixes a bunch of smaller issues.
https://www.torproject.org/download/download
Note that the tarball and git tags are signed by my newer (4096 bit)
gpg key, 0x19F78451.
(Packages coming eventually.)
Changes in version 0.2.3.11-alpha - 2012-01-22
o Major features:
- Now that Tor 0.2.0.x is completely deprecated, enable the final
part of "Proposal 110: Avoiding infinite length circuits" by
refusing all circuit-extend requests that do not use a relay_early
cell. This change helps Tor resist a class of denial-of-service
attacks by limiting the maximum circuit length.
- Adjust the number of introduction points that a hidden service
will try to maintain based on how long its introduction points
remain in use and how many introductions they handle. Fixes
part of bug 3825.
- Try to use system facilities for enumerating local interface
addresses, before falling back to our old approach (which was
binding a UDP socket, and calling getsockname() on it). That
approach was scaring OS X users whose draconian firewall
software warned about binding to UDP sockets, regardless of
whether packets were sent. Now we try to use getifaddrs(),
SIOCGIFCONF, or GetAdaptersAddresses(), depending on what the
system supports. Resolves ticket 1827.
o Major security workaround:
- When building or running with any version of OpenSSL earlier
than 0.9.8s or 1.0.0f, disable SSLv3 support. These OpenSSL
versions have a bug (CVE-2011-4576) in which their block cipher
padding includes uninitialized data, potentially leaking sensitive
information to any peer with whom they make a SSLv3 connection. Tor
does not use SSL v3 by default, but a hostile client or server
could force an SSLv3 connection in order to gain information that
they shouldn't have been able to get. The best solution here is to
upgrade to OpenSSL 0.9.8s or 1.0.0f (or later). But when building
or running with a non-upgraded OpenSSL, we disable SSLv3 entirely
to make sure that the bug can't happen.
o Major bugfixes:
- Fix the SOCKET_OK test that we use to tell when socket
creation fails so that it works on Win64. Fixes part of bug 4533;
bugfix on 0.2.2.29-beta. Bug found by wanoskarnet.
- Correct our replacements for the timeradd() and timersub() functions
on platforms that lack them (for example, Windows). The timersub()
function is used when expiring circuits, while timeradd() is
currently unused. Bug report and patch by Vektor. Fixes bug 4778;
bugfix on 0.2.2.24-alpha and 0.2.3.1-alpha.
- Do not use OpenSSL 1.0.0's counter mode: it has a critical bug
that was fixed in OpenSSL 1.0.0a. We test for the counter mode
bug at runtime, not compile time, because some distributions hack
their OpenSSL to mis-report its version. Fixes bug 4779; bugfix
on 0.2.3.9-alpha. Found by Pascal.
o Minor features (controller):
- Use absolute path names when reporting the torrc filename in the
control protocol, so a controller can more easily find the torrc
file. Resolves bug 1101.
- Extend the control protocol to report flags that control a circuit's
path selection in CIRC events and in replies to 'GETINFO
circuit-status'. Implements part of ticket 2411.
- Extend the control protocol to report the hidden service address
and current state of a hidden-service-related circuit in CIRC
events and in replies to 'GETINFO circuit-status'. Implements part
of ticket 2411.
- When reporting the path to the cookie file to the controller,
give an absolute path. Resolves ticket 4881.
- Allow controllers to request an event notification whenever a
circuit is cannibalized or its purpose is changed. Implements
part of ticket 3457.
- Include the creation time of a circuit in CIRC and CIRC2
control-port events and the list produced by the 'GETINFO
circuit-status' control-port command.
o Minor features (directory authorities):
- Directory authorities now reject versions of Tor older than
0.2.1.30, and Tor versions between 0.2.2.1-alpha and 0.2.2.20-alpha
inclusive. These versions accounted for only a small fraction of
the Tor network, and have numerous known security issues. Resolves
issue 4788.
- Authority operators can now vote for all relays in a given
set of countries to be BadDir/BadExit/Invalid/Rejected.
- Provide two consensus parameters (FastFlagMinThreshold and
FastFlagMaxThreshold) to control the range of allowable bandwidths
for the Fast directory flag. These allow authorities to run
experiments on appropriate requirements for being a "Fast" node.
The AuthDirFastGuarantee config value still applies.
- Document the GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays
directory authority option (introduced in Tor 0.2.2.34).
o Minor features (other):
- Don't disable the DirPort when we cannot exceed our AccountingMax
limit during this interval because the effective bandwidthrate is
low enough. This is useful in a situation where AccountMax is only
used as an additional safeguard or to provide statistics.
- Prepend an informative header to generated dynamic_dh_params files.
- If EntryNodes are given, but UseEntryGuards is set to 0, warn that
EntryNodes will have no effect. Resolves issue 2571.
- Log more useful messages when we fail to disable debugger
attachment.
- Log which authority we're missing votes from when we go to fetch
them from the other auths.
- Log (at debug level) whenever a circuit's purpose is changed.
- Add missing documentation for the MaxClientCircuitsPending,
UseMicrodescriptors, UserspaceIOCPBuffers, and
_UseFilteringSSLBufferevents options, all introduced during
the 0.2.3.x series.
- Update to the January 3 2012 Maxmind GeoLite Country database.
o Minor bugfixes (hidden services):
- Don't close hidden service client circuits which have almost
finished connecting to their destination when they reach
the normal circuit-build timeout. Previously, we would close
introduction circuits which are waiting for an acknowledgement
from the introduction point, and rendezvous circuits which have
been specified in an INTRODUCE1 cell sent to a hidden service,
after the normal CBT. Now, we mark them as 'timed out', and launch
another rendezvous attempt in parallel. This behavior change can
be disabled using the new CloseHSClientCircuitsImmediatelyOnTimeout
option. Fixes part of bug 1297; bugfix on 0.2.2.2-alpha.
- Don't close hidden-service-side rendezvous circuits when they
reach the normal circuit-build timeout. This behaviour change can
be disabled using the new
CloseHSServiceRendCircuitsImmediatelyOnTimeout option. Fixes the
remaining part of bug 1297; bugfix on 0.2.2.2-alpha.
- Make sure we never mark the wrong rendezvous circuit as having
had its introduction cell acknowleged by the introduction-point
relay. Previously, when we received an INTRODUCE_ACK cell on a
client-side hidden-service introduction circuit, we might have
marked a rendezvous circuit other than the one we specified in
the INTRODUCE1 cell as INTRO_ACKED, which would have produced
a warning message and interfered with the hidden service
connection-establishment process. Fixes bug 4759; bugfix on
0.2.3.3-alpha, when we added the stream-isolation feature which
might cause Tor to open multiple rendezvous circuits for the same
hidden service.
- Don't trigger an assertion failure when we mark a new client-side
hidden-service introduction circuit for close during the process
of creating it. Fixes bug 4796; bugfix on 0.2.3.6-alpha. Reported
by murb.
o Minor bugfixes (log messages):
- Correctly spell "connect" in a log message on failure to create a
controlsocket. Fixes bug 4803; bugfix on 0.2.2.26-beta and
0.2.3.2-alpha.
- Fix a typo in a log message in rend_service_rendezvous_has_opened().
Fixes bug 4856; bugfix on Tor 0.0.6.
- Fix the log message describing how we work around discovering
that our version is the ill-fated OpenSSL 0.9.8l. Fixes bug
4837; bugfix on 0.2.2.9-alpha.
- When logging about a disallowed .exit name, do not also call it
an "invalid onion address". Fixes bug 3325; bugfix on 0.2.2.9-alpha.
o Minor bugfixes (build fixes):
- During configure, detect when we're building with clang version
3.0 or lower and disable the -Wnormalized=id and -Woverride-init
CFLAGS. clang doesn't support them yet.
- During configure, search for library containing cos function as
libm lives in libcore on some platforms (BeOS/Haiku). Linking
against libm was hard-coded before. Fixes the first part of bug
4727; bugfix on 0.2.2.2-alpha. Patch and analysis by Martin Hebnes
Pedersen.
- Detect attempts to build Tor on (as yet hypothetical) versions
of Windows where sizeof(intptr_t) != sizeof(SOCKET). Partial
fix for bug 4533. Bugfix on 0.2.2.28-beta.
- Preprocessor directives should not be put inside the arguments
of a macro. This would break compilation with GCC releases prior
to version 3.3. We would never recommend such an old GCC version,
but it is apparently required for binary compatibility on some
platforms (namely, certain builds of Haiku). Fixes the other part
of bug 4727; bugfix on 0.2.3.3-alpha. Patch and analysis by Martin
Hebnes Pedersen.
o Minor bugfixes (other):
- Older Linux kernels erroneously respond to strange nmap behavior
by having accept() return successfully with a zero-length
socket. When this happens, just close the connection. Previously,
we would try harder to learn the remote address: but there was
no such remote address to learn, and our method for trying to
learn it was incorrect. Fixes bugs 1240, 4745, and 4747. Bugfix
on 0.1.0.3-rc. Reported and diagnosed by "r1eo".
- Fix null-pointer access that could occur if TLS allocation failed.
Fixes bug 4531; bugfix on 0.2.0.20-rc. Found by "troll_un". This was
erroneously listed as fixed in 0.2.3.9-alpha, but the fix had
accidentally been reverted.
- Fix our implementation of crypto_random_hostname() so it can't
overflow on ridiculously large inputs. (No Tor version has ever
provided this kind of bad inputs, but let's be correct in depth.)
Fixes bug 4413; bugfix on 0.2.2.9-alpha. Fix by Stephen Palmateer.
- Find more places in the code that should have been testing for
invalid sockets using the SOCKET_OK macro. Required for a fix
for bug 4533. Bugfix on 0.2.2.28-beta.
- Fix an assertion failure when, while running with bufferevents, a
connection finishes connecting after it is marked for close, but
before it is closed. Fixes bug 4697; bugfix on 0.2.3.1-alpha.
- test_util_spawn_background_ok() hardcoded the expected value
for ENOENT to 2. This isn't portable as error numbers are
platform specific, and particularly the hurd has ENOENT at
0x40000002. Construct expected string at runtime, using the correct
value for ENOENT. Fixes bug 4733; bugfix on 0.2.3.1-alpha.
- Reject attempts to disable DisableDebuggerAttachment while Tor is
running. Fixes bug 4650; bugfix on 0.2.3.9-alpha.
- Use an appropriate-width type for sockets in tor-fw-helper on
win64. Fixes bug 1983 at last. Bugfix on 0.2.3.9-alpha.
o Feature removal:
- When sending or relaying a RELAY_EARLY cell, we used to convert
it to a RELAY cell if the connection was using the v1 link
protocol. This was a workaround for older versions of Tor, which
didn't handle RELAY_EARLY cells properly. Now that all supported
versions can handle RELAY_EARLY cells, and now that we're enforcing
the "no RELAY_EXTEND commands except in RELAY_EARLY cells" rule,
remove this workaround. Addresses bug 4786.
o Code simplifications and refactoring:
- Use OpenSSL's built-in SSL_state_string_long() instead of our
own homebrewed ssl_state_to_string() replacement. Patch from
Emile Snyder. Fixes bug 4653.
- Use macros to indicate OpenSSL versions, so we don't need to worry
about accidental hexadecimal bit shifts.
- Remove some workaround code for OpenSSL 0.9.6 (which is no longer
supported).
- Convert more instances of tor_snprintf+tor_strdup into tor_asprintf.
- Use the smartlist_add_asprintf() alias more consistently.
- Use a TOR_INVALID_SOCKET macro when initializing a socket to an
invalid value, rather than just -1.
- Rename a handful of old identifiers, mostly related to crypto
structures and crypto functions. By convention, our "create an
object" functions are called "type_new()", our "free an object"
functions are called "type_free()", and our types indicate that
they are types only with a final "_t". But a handful of older
types and functions broke these rules, with function names like
"type_create" or "subsystem_op_type", or with type names like
type_env_t.
Attachment:
signature.asc
Description: Digital signature
_______________________________________________ tor-talk mailing list tor-talk@xxxxxxxxxxxxxxxxxxxx https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-talk