ChangeLog

Changes in version 0.2.3.18-rc - 2012-06-28
  Tor 0.2.3.18-rc is the first release candidate for the Tor 0.2.3.x
  series. It fixes a few smaller bugs, but generally appears stable.
  Please test it and let us know whether it is!

  o Major bugfixes:
    - Allow wildcarded mapaddress targets to be specified on the
      controlport. Partially fixes bug 6244; bugfix on 0.2.3.9-alpha.
    - Make our linker option detection code more robust against linkers
      such as on FreeBSD 8, where a bad combination of options completes
      successfully but makes an unrunnable binary. Fixes bug 6173;
      bugfix on 0.2.3.17-beta.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Avoid a false positive in the util/threads unit test by increasing
      the maximum timeout time. Fixes bug 6227; bugfix on 0.2.0.4-alpha.
    - Replace "Sending publish request" log messages with "Launching
      upload", so that they no longer confusingly imply that we're
      sending something to a directory we might not even be connected
      to yet. Fixes bug 3311; bugfix on 0.2.0.10-alpha.
    - Make sure to set *socket_error in all error cases in
      connection_connect(), so it can't produce a warning about
      errno being zero from errno_to_orconn_end_reason(). Bugfix on
      0.2.1.1-alpha; resolves ticket 6028.
    - Downgrade "Got a certificate, but we already have it" log messages
      from warning to info, except when we're a dirauth. Fixes bug 5238;
      bugfix on 0.2.1.7-alpha.
    - When checking for requested signatures on the latest consensus
      before serving it to a client, make sure to check the right
      consensus flavor. Bugfix on 0.2.2.6-alpha.
    - Downgrade "eventdns rejected address" message to LOG_PROTOCOL_WARN.
      Fixes bug 5932; bugfix on 0.2.2.7-alpha.

  o Minor bugfixes (on 0.2.3.x):
    - Make format_helper_exit_status() avoid unnecessary space padding
      and stop confusing log_from_pipe(). Fixes ticket 5557; bugfix
      on 0.2.3.1-alpha.
    - Downgrade a message about cleaning the microdescriptor cache to
      "info" from "notice". Fixes bug 6238; bugfix on 0.2.3.1-alpha.
    - Log a BUG message at severity INFO if we have a networkstatus with
      a missing entry for some microdescriptor. Continues on a patch
      to 0.2.3.2-alpha.
    - Improve the log message when a managed proxy fails to launch. Fixes
      bug 5099; bugfix on 0.2.3.6-alpha.
    - Don't do DNS lookups when parsing corrupted managed proxy protocol
      messages. Fixes bug 6226; bugfix on 0.2.3.6-alpha.
    - When formatting wildcarded address mappings for the controller,
      be sure to include "*." as appropriate. Partially fixes bug 6244;
      bugfix on 0.2.3.9-alpha.
    - Avoid a warning caused by using strcspn() from glibc with clang 3.0.
      Bugfix on 0.2.3.13-alpha.
    - Stop logging messages about running with circuit timeout learning
      enabled at severity LD_BUG. Fixes bug 6169; bugfix on 0.2.3.17-beta.
    - Disable a spurious warning about reading on a marked and flushing
      connection. We shouldn't be doing that, but apparently we
      sometimes do. Fixes bug 6203; bugfix on 0.2.3.17-beta.
    - Fix a bug that stopped AllowDotExit from working on addresses
      that had an entry in the DNS cache. Fixes bug 6211; bugfix on
      0.2.3.17-beta.

  o Code simplification, refactoring, unit tests:
    - Move tor_gettimeofday_cached() into compat_libevent.c, and use
      Libevent's notion of cached time when possible.
    - Remove duplicate code for invoking getrlimit() from control.c.
    - Add a unit test for the environment_variable_names_equal function.

  o Documentation:
    - Document the --defaults-torrc option, and the new (in 0.2.3)
      semantics for overriding, extending, and clearing lists of
      options. Closes bug 4748.


Changes in version 0.2.3.17-beta - 2012-06-15
  Tor 0.2.3.17-beta enables compiler and linker hardening by default,
  gets our TLS handshake back on track for being able to blend in with
  Firefox, fixes a big bug in 0.2.3.16-alpha that broke Tor's interaction
  with Vidalia, and otherwise continues to get us closer to a release
  candidate.

  o Major features:
    - Enable gcc and ld hardening by default. Resolves ticket 5210.
    - Update TLS cipher list to match Firefox 8 and later. Resolves
      ticket 4744.
    - Implement the client side of proposal 198: remove support for
      clients falsely claiming to support standard ciphersuites that
      they can actually provide. As of modern OpenSSL versions, it's not
      necessary to fake any standard ciphersuite, and doing so prevents
      us from using better ciphersuites in the future, since servers
      can't know whether an advertised ciphersuite is really supported or
      not. Some hosts -- notably, ones with very old versions of OpenSSL
      or where OpenSSL has been built with ECC disabled -- will stand
      out because of this change; TBB users should not be affected.

  o Major bugfixes:
    - Change the default value for DynamicDHGroups (introduced in
      0.2.3.9-alpha) to 0. This feature can make Tor relays less
      identifiable by their use of the mod_ssl DH group, but at
      the cost of some usability (#4721) and bridge tracing (#6087)
      regressions. Resolves ticket 5598.
    - Send a CRLF at the end of each STATUS_* control protocol event. This
      bug tickled a bug in Vidalia which would make it freeze. Fixes
      bug 6094; bugfix on 0.2.3.16-alpha.

  o Minor bugfixes:
    - Disable writing on marked-for-close connections when they are
      blocked on bandwidth, to prevent busy-looping in Libevent. Fixes
      bug 5263; bugfix on 0.0.2pre13, where we first added a special
      case for flushing marked connections.
    - Detect SSL handshake even when the initial attempt to write the
      server hello fails. Fixes bug 4592; bugfix on 0.2.0.13-alpha.
    - Change the AllowDotExit rules so they should actually work.
      We now enforce AllowDotExit only immediately after receiving an
      address via SOCKS or DNSPort: other sources are free to provide
      .exit addresses after the resolution occurs. Fixes bug 3940;
      bugfix on 0.2.2.1-alpha.
    - Fix a (harmless) integer overflow in cell statistics reported by
      some fast relays. Fixes bug 5849; bugfix on 0.2.2.1-alpha.
    - Make sure circuitbuild.c checks LearnCircuitBuildTimeout in all the
      right places and never depends on the consensus parameters or
      computes adaptive timeouts when it is disabled. Fixes bug 5049;
      bugfix on 0.2.2.14-alpha.
    - When building Tor on Windows with -DUNICODE (not default), ensure
      that error messages, filenames, and DNS server names are always
      NUL-terminated when we convert them to a single-byte encoding.
      Fixes bug 5909; bugfix on 0.2.2.16-alpha.
    - Make Tor build correctly again with -DUNICODE -D_UNICODE defined.
      Fixes bug 6097; bugfix on 0.2.2.16-alpha.
    - Fix an edge case where TestingTorNetwork is set but the authorities
      and relays all have an uptime of zero, where the private Tor network
      could briefly lack support for hidden services. Fixes bug 3886;
      bugfix on 0.2.2.18-alpha.
    - Correct the manpage's descriptions for the default values of
      DirReqStatistics and ExtraInfoStatistics. Fixes bug 2865; bugfix
      on 0.2.3.1-alpha.
    - Fix the documentation for the --hush and --quiet command line
      options, which changed their behavior back in 0.2.3.3-alpha.
    - Fix compilation warning with clang 3.1. Fixes bug 6141; bugfix on
      0.2.3.11-alpha.

  o Minor features:
    - Rate-limit the "Weighted bandwidth is 0.000000" message, and add
      more information to it, so that we can track it down in case it
      returns again. Mitigates bug 5235.
    - Check CircuitBuildTimeout and LearnCircuitBuildTimeout in
      options_validate(); warn if LearnCircuitBuildTimeout is disabled and
      CircuitBuildTimeout is set unreasonably low. Resolves ticket 5452.
    - Warn the user when HTTPProxy, but no other proxy type, is
      configured. This can cause surprising behavior: it doesn't send
      all of Tor's traffic over the HTTPProxy -- it sends unencrypted
      directory traffic only. Resolves ticket 4663.
    - Issue a notice if a guard completes less than 40% of your circuits.
      Threshold is configurable by torrc option PathBiasNoticeRate and
      consensus parameter pb_noticepct. There is additional, off-by-
      default code to disable guards which fail too many circuits.
      Addresses ticket 5458.
    - Update to the June 6 2012 Maxmind GeoLite Country database.

  o Code simplifications and refactoring:
    - Remove validate_pluggable_transports_config(): its warning
      message is now handled by connection_or_connect().


Changes in version 0.2.2.37 - 2012-06-06
  Tor 0.2.2.37 introduces a workaround for a critical renegotiation
  bug in OpenSSL 1.0.1 (where 20% of the Tor network can't talk to itself
  currently).

  o Major bugfixes:
    - Work around a bug in OpenSSL that broke renegotiation with TLS
      1.1 and TLS 1.2. Without this workaround, all attempts to speak
      the v2 Tor connection protocol when both sides were using OpenSSL
      1.0.1 would fail. Resolves ticket 6033.
    - When waiting for a client to renegotiate, don't allow it to add
      any bytes to the input buffer. This fixes a potential DoS issue.
      Fixes bugs 5934 and 6007; bugfix on 0.2.0.20-rc.
    - Fix an edge case where if we fetch or publish a hidden service
      descriptor, we might build a 4-hop circuit and then use that circuit
      for exiting afterwards -- even if the new last hop doesn't obey our
      ExitNodes config option. Fixes bug 5283; bugfix on 0.2.0.10-alpha.

  o Minor bugfixes:
    - Fix a build warning with Clang 3.1 related to our use of vasprintf.
      Fixes bug 5969. Bugfix on 0.2.2.11-alpha.

  o Minor features:
    - Tell GCC and Clang to check for any errors in format strings passed
      to the tor_v*(print|scan)f functions.


Changes in version 0.2.3.16-alpha - 2012-06-05
  Tor 0.2.3.16-alpha introduces a workaround for a critical renegotiation
  bug in OpenSSL 1.0.1 (where 20% of the Tor network can't talk to itself
  currently). It also fixes a variety of smaller bugs and other cleanups
  that get us closer to a release candidate.

  o Major bugfixes (general):
    - Work around a bug in OpenSSL that broke renegotiation with TLS
      1.1 and TLS 1.2. Without this workaround, all attempts to speak
      the v2 Tor connection protocol when both sides were using OpenSSL
      1.0.1 would fail. Resolves ticket 6033.
    - When waiting for a client to renegotiate, don't allow it to add
      any bytes to the input buffer. This fixes a potential DoS issue.
      Fixes bugs 5934 and 6007; bugfix on 0.2.0.20-rc.
    - Pass correct OR address to managed proxies (like obfsproxy),
      even when ORListenAddress is used. Fixes bug 4865; bugfix on
      0.2.3.9-alpha.
    - The advertised platform of a router now includes only its operating
      system's name (e.g., "Linux", "Darwin", "Windows 7"), and not its
      service pack level (for Windows) or its CPU architecture (for Unix).
      We also no longer include the "git-XYZ" tag in the version. Resolves
      part of bug 2988.

  o Major bugfixes (clients):
    - If we are unable to find any exit that supports our predicted ports,
      stop calling them predicted, so that we don't loop and build
      hopeless circuits indefinitely. Fixes bug 3296; bugfix on 0.0.9pre6,
      which introduced predicted ports.
    - Fix an edge case where if we fetch or publish a hidden service
      descriptor, we might build a 4-hop circuit and then use that circuit
      for exiting afterwards -- even if the new last hop doesn't obey our
      ExitNodes config option. Fixes bug 5283; bugfix on 0.2.0.10-alpha.
    - Check at each new consensus whether our entry guards were picked
      long enough ago that we should rotate them. Previously, we only
      did this check at startup, which could lead to us holding a guard
      indefinitely. Fixes bug 5380; bugfix on 0.2.1.14-rc.
    - When fetching a bridge descriptor from a bridge authority,
      always do so anonymously, whether we have been able to open
      circuits or not. Partial fix for bug 1938; bugfix on 2.0.7-alpha.
      This behavior makes it *safer* to use UpdateBridgesFromAuthority,
      but we'll need to wait for bug 6010 before it's actually usable.

  o Major bugfixes (directory authorities):
    - When computing weight parameters, behave more robustly in the
      presence of a bad bwweightscale value. Previously, the authorities
      would crash if they agreed on a sufficiently broken weight_scale
      value: now, they use a reasonable default and carry on. Partial
      fix for 5786; bugfix on 0.2.2.17-alpha.
    - Check more thoroughly to prevent a rogue authority from
      double-voting on any consensus directory parameter. Previously,
      authorities would crash in this case if the total number of
      votes for any parameter exceeded the number of active voters,
      but would let it pass otherwise. Partial fix for bug 5786; bugfix
      on 0.2.2.2-alpha.

  o Minor features:
    - Rate-limit log messages when asked to connect anonymously to
      a private address. When these hit, they tended to hit fast and
      often. Also, don't bother trying to connect to addresses that we
      are sure will resolve to 127.0.0.1: getting 127.0.0.1 in a directory
      reply makes us think we have been lied to, even when the address the
      client tried to connect to was "localhost." Resolves ticket 2822.
    - Allow packagers to insert an extra string in server descriptor
      platform lines by setting the preprocessor variable TOR_BUILD_TAG.
      Resolves the rest of ticket 2988.
    - Raise the threshold of server descriptors needed (75%) and exit
      server descriptors needed (50%) before we will declare ourselves
      bootstrapped. This will make clients start building circuits a
      little later, but makes the initially constructed circuits less
      skewed and less in conflict with further directory fetches. Fixes
      ticket 3196.
    - Close any connection that sends unrecognized junk before the
      handshake. Solves an issue noted in bug 4369.
    - Improve log messages about managed transports. Resolves ticket 5070.
    - Tag a bridge's descriptor as "never to be sent unencrypted".
      This shouldn't matter, since bridges don't open non-anonymous
      connections to the bridge authority and don't allow unencrypted
      directory connections from clients, but we might as well make
      sure. Closes bug 5139.
    - Expose our view of whether we have gone dormant to the controller,
      via a new "GETINFO dormant" value. Torbutton and other controllers
      can use this to avoid doing periodic requests through Tor while
      it's dormant (bug 4718). Fixes bug 5954.
    - Tell GCC and Clang to check for any errors in format strings passed
      to the tor_v*(print|scan)f functions.
    - Update to the May 1 2012 Maxmind GeoLite Country database.

  o Minor bugfixes (already included in 0.2.2.36):
    - Reject out-of-range times like 23:59:61 in parse_rfc1123_time().
      Fixes bug 5346; bugfix on 0.0.8pre3.
    - Correct parsing of certain date types in parse_http_time().
      Without this patch, If-Modified-Since would behave
      incorrectly. Fixes bug 5346; bugfix on 0.2.0.2-alpha. Patch from
      Esteban Manchado Velázques.
    - Make our number-parsing functions always treat too-large values
      as an error, even when those values exceed the width of the
      underlying type. Previously, if the caller provided these
      functions with minima or maxima set to the extreme values of the
      underlying integer type, these functions would return those
      values on overflow rather than treating overflow as an error.
      Fixes part of bug 5786; bugfix on 0.0.9.
    - If we hit the error case where routerlist_insert() replaces an
      existing (old) server descriptor, make sure to remove that
      server descriptor from the old_routers list. Fix related to bug
      1776. Bugfix on 0.2.2.18-alpha.
    - Clarify the behavior of MaxCircuitDirtiness with hidden service
      circuits. Fixes issue 5259.

  o Minor bugfixes (coding cleanup, on 0.2.2.x and earlier):
    - Prevent a null-pointer dereference when receiving a data cell
      for a nonexistent stream when the circuit in question has an
      empty deliver window. We don't believe this is triggerable,
      since we don't currently allow deliver windows to become empty,
      but the logic is tricky enough that it's better to make the code
      robust. Fixes bug 5541; bugfix on 0.0.2pre14.
    - Fix a memory leak when trying to launch a DNS request when the
      network is disabled or the nameservers are unconfigurable. Fixes
      bug 5916; bugfix on Tor 0.1.2.1-alpha (for the unconfigurable
      nameserver case) and on 0.2.3.9-alpha (for the DisableNetwork case).
    - Don't hold a Windows file handle open for every file mapping;
      the file mapping handle is sufficient. Fixes bug 5951; bugfix on
      0.1.2.1-alpha.
    - Avoid O(n^2) performance characteristics when parsing a large
      extrainfo cache. Fixes bug 5828; bugfix on 0.2.0.1-alpha.
    - Format more doubles with %f, not %lf. Patch from grarpamp to make
      Tor build correctly on older BSDs again. Fixes bug 3894; bugfix on
      Tor 0.2.0.8-alpha.
    - Make our replacement implementation of strtok_r() compatible with
      the standard behavior of strtok_r(). Patch by nils. Fixes bug 5091;
      bugfix on 0.2.2.1-alpha.
    - Fix a NULL-pointer dereference on a badly formed
      SETCIRCUITPURPOSE command. Found by mikeyc. Fixes bug 5796;
      bugfix on 0.2.2.9-alpha.
    - Fix a build warning with Clang 3.1 related to our use of vasprintf.
      Fixes bug 5969. Bugfix on 0.2.2.11-alpha.
    - Defensively refactor rend_mid_rendezvous() so that protocol
      violations and length checks happen in the beginning. Fixes
      bug 5645.
    - Set _WIN32_WINNT to 0x0501 consistently throughout the code, so
      that IPv6 stuff will compile on MSVC, and compilation issues
      will be easier to track down. Fixes bug 5861.

  o Minor bugfixes (correctness, on 0.2.2.x and earlier):
    - Exit nodes now correctly report EADDRINUSE and EADDRNOTAVAIL as
      resource exhaustion, so that clients can adjust their load to
      try other exits. Fixes bug 4710; bugfix on 0.1.0.1-rc, which
      started using END_STREAM_REASON_RESOURCELIMIT.
    - Don't check for whether the address we're using for outbound
      connections has changed until after the outbound connection has
      completed. On Windows, getsockname() doesn't succeed until the
      connection is finished. Fixes bug 5374; bugfix on 0.1.1.14-alpha.
    - If the configuration tries to set MyFamily on a bridge, refuse to
      do so, and warn about the security implications. Fixes bug 4657;
      bugfix on 0.2.0.3-alpha.
    - If the client fails to set a reasonable set of ciphersuites
      during its v2 handshake renegotiation, allow the renegotiation to
      continue nevertheless (i.e. send all the required certificates).
      Fixes bug 4591; bugfix on 0.2.0.20-rc.
    - When we receive a SIGHUP and the controller __ReloadTorrcOnSIGHUP
      option is set to 0 (which Vidalia version 0.2.16 now does when
      a SAVECONF attempt fails), perform other actions that SIGHUP
      usually causes (like reopening the logs). Fixes bug 5095; bugfix
      on 0.2.1.9-alpha.
    - If we fail to write a microdescriptor to the disk cache, do not
      continue replacing the old microdescriptor file. Fixes bug 2954;
      bugfix on 0.2.2.6-alpha.
    - Exit nodes don't need to fetch certificates for authorities that
      they don't recognize; only directory authorities, bridges,
      and caches need to do that. Fixes part of bug 2297; bugfix on
      0.2.2.11-alpha.
    - Correctly handle checking the permissions on the parent
      directory of a control socket in the root directory. Bug found
      by Esteban Manchado Velázquez. Fixes bug 5089; bugfix on Tor
      0.2.2.26-beta.
    - When told to add a bridge with the same digest as a preexisting
      bridge but a different addr:port, change the addr:port as
      requested. Previously we would not notice the change. Fixes half
      of bug 5603; fix on 0.2.2.26-beta.
    - End AUTHCHALLENGE error messages (in the control protocol) with
      a CRLF. Fixes bug 5760; bugfix on 0.2.2.36 and 0.2.3.13-alpha.

  o Minor bugfixes (on 0.2.3.x):
    - Turn an assertion (that the number of handshakes received as a
      server is not < 1) into a warning. Fixes bug 4873; bugfix on
      0.2.3.1-alpha.
    - Format IPv4 addresses correctly in ADDRMAP events. (Previously,
      we had reversed them when the answer was cached.) Fixes bug
      5723; bugfix on 0.2.3.1-alpha.
    - Work correctly on Linux systems with accept4 support advertised in
      their headers, but without accept4 support in the kernel. Fix
      by murb. Fixes bug 5762; bugfix on 0.2.3.1-alpha.
    - When told to add a bridge with the same addr:port as a preexisting
      bridge but a different transport, change the transport as
      requested. Previously we would not notice the change. Fixes half
      of bug 5603; fix on 0.2.3.2-alpha.
    - Avoid a "double-reply" warning when replying to a SOCKS request
      with a parse error. Patch from Fabian Keil. Fixes bug 4108;
      bugfix on 0.2.3.4-alpha.
    - Fix a bug where a bridge authority crashes if it has seen no
      directory requests when it's time to write statistics to disk.
      Fixes bug 5891; bugfix on 0.2.3.6-alpha. Also fixes bug 5508 in
      a better way.
    - Don't try to open non-control listeners when DisableNetwork is set.
      Previously, we'd open all listeners, then immediately close them.
      Fixes bug 5604; bugfix on 0.2.3.9-alpha.
    - Don't abort the managed proxy protocol if the managed proxy
      sends us an unrecognized line; ignore it instead. Fixes bug
      5910; bugfix on 0.2.3.9-alpha.
    - Fix a compile warning in crypto.c when compiling with clang 3.1.
      Fixes bug 5969, bugfix on 0.2.3.9-alpha.
    - Fix a compilation issue on GNU Hurd, which doesn't have PATH_MAX.
      Fixes bug 5355; bugfix on 0.2.3.11-alpha.
    - Remove bogus definition of "_WIN32" from src/win32/orconfig.h, to
      unbreak the MSVC build. Fixes bug 5858; bugfix on 0.2.3.12-alpha.
    - Resolve numerous small warnings and build issues with MSVC. Resolves
      bug 5859.

  o Documentation fixes:
    - Improve the manual's documentation for the NT Service command-line
      options. Addresses ticket 3964.
    - Clarify SessionGroup documentation slightly; resolves ticket 5437.
    - Document the changes to the ORPort and DirPort options, and the
      fact that {OR/Dir}ListenAddress is now unnecessary (and
      therefore deprecated). Resolves ticket 5597.

  o Removed files:
    - Remove the torrc.bridge file: we don't use it for anything, and
      it had become badly desynchronized from torrc.sample. Resolves
      bug 5622.


Changes in version 0.2.2.36 - 2012-05-24
  Tor 0.2.2.36 updates the addresses for two of the eight directory
  authorities, fixes some potential anonymity and security issues,
  and fixes several crash bugs.

  Tor 0.2.1.x has reached its end-of-life. Those Tor versions have many
  known flaws, and nobody should be using them. You should upgrade. If
  you're using a Linux or BSD and its packages are obsolete, stop using
  those packages and upgrade anyway.

  o Directory authority changes:
    - Change IP address for maatuska (v3 directory authority).
    - Change IP address for ides (v3 directory authority), and rename
      it to turtles.

  o Security fixes:
    - 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.
    - Never use a bridge or a controller-supplied node as an exit, even
      if its exit policy allows it. Found by wanoskarnet. Fixes bug
      5342. Bugfix on 0.1.1.15-rc (for controller-purpose descriptors)
      and 0.2.0.3-alpha (for bridge-purpose descriptors).
    - Only build circuits if we have a sufficient threshold of the total
      descriptors that are marked in the consensus with the "Exit"
      flag. This mitigates an attack proposed by wanoskarnet, in which
      all of a client's bridges collude to restrict the exit nodes that
      the client knows about. Fixes bug 5343.
    - Provide controllers with a safer way to implement the cookie
      authentication mechanism. With the old method, if another locally
      running program could convince a controller that it was the Tor
      process, then that program could trick the controller into telling
      it the contents of an arbitrary 32-byte file. The new "SAFECOOKIE"
      authentication method uses a challenge-response approach to prevent
      this attack. Fixes bug 5185; implements proposal 193.

  o Major bugfixes:
    - Avoid logging uninitialized data when unable to decode a hidden
      service descriptor cookie. Fixes bug 5647; bugfix on 0.2.1.5-alpha.
    - Avoid a client-side assertion failure when receiving an INTRODUCE2
      cell on a general purpose circuit. Fixes bug 5644; bugfix on
      0.2.1.6-alpha.
    - Fix builds when the path to sed, openssl, or sha1sum contains
      spaces, which is pretty common on Windows. Fixes bug 5065; bugfix
      on 0.2.2.1-alpha.
    - 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.
    - 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.

  o Minor bugfixes:
    - Reject out-of-range times like 23:59:61 in parse_rfc1123_time().
      Fixes bug 5346; bugfix on 0.0.8pre3.
    - Make our number-parsing functions always treat too-large values
      as an error, even when those values exceed the width of the
      underlying type. Previously, if the caller provided these
      functions with minima or maxima set to the extreme values of the
      underlying integer type, these functions would return those
      values on overflow rather than treating overflow as an error.
      Fixes part of bug 5786; bugfix on 0.0.9.
    - 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".
    - Correct parsing of certain date types in parse_http_time().
      Without this patch, If-Modified-Since would behave
      incorrectly. Fixes bug 5346; bugfix on 0.2.0.2-alpha. Patch from
      Esteban Manchado Velázques.
    - Change the BridgePassword feature (part of the "bridge community"
      design, which is not yet implemented) to use a time-independent
      comparison. The old behavior might have allowed an adversary
      to use timing to guess the BridgePassword value. Fixes bug 5543;
      bugfix on 0.2.0.14-alpha.
    - Detect and reject certain misformed escape sequences in
      configuration values. Previously, these values would cause us
      to crash if received in a torrc file or over an authenticated
      control port. Bug found by Esteban Manchado Velázquez, and
      independently by Robert Connolly from Matta Consulting who further
      noted that it allows a post-authentication heap overflow. Patch
      by Alexander Schrijver. Fixes bugs 5090 and 5402 (CVE 2012-1668);
      bugfix on 0.2.0.16-alpha.
    - Fix a compile warning when using the --enable-openbsd-malloc
      configure option. Fixes bug 5340; bugfix on 0.2.0.20-rc.
    - 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.
    - When sending an HTTP/1.1 proxy request, include a Host header.
      Fixes bug 5593; bugfix on 0.2.2.1-alpha.
    - Fix a NULL-pointer dereference on a badly formed SETCIRCUITPURPOSE
      command. Found by mikeyc. Fixes bug 5796; bugfix on 0.2.2.9-alpha.
    - If we hit the error case where routerlist_insert() replaces an
      existing (old) server descriptor, make sure to remove that
      server descriptor from the old_routers list. Fix related to bug
      1776. Bugfix on 0.2.2.18-alpha.

  o Minor bugfixes (documentation and log messages):
    - Fix a typo in a log message in rend_service_rendezvous_has_opened().
      Fixes bug 4856; bugfix on Tor 0.0.6.
    - Update "ClientOnly" man page entry to explain that there isn't
      really any point to messing with it. Resolves ticket 5005.
    - Document the GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays
      directory authority option (introduced in Tor 0.2.2.34).
    - Downgrade the "We're missing a certificate" message from notice
      to info: people kept mistaking it for a real problem, whereas it
      is seldom the problem even when we are failing to bootstrap. Fixes
      bug 5067; bugfix on 0.2.0.10-alpha.
    - Correctly spell "connect" in a log message on failure to create a
      controlsocket. Fixes bug 4803; bugfix on 0.2.2.26-beta.
    - Clarify the behavior of MaxCircuitDirtiness with hidden service
      circuits. Fixes issue 5259.

  o Minor features:
    - 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.
    - Update to the May 1 2012 Maxmind GeoLite Country database.

  - 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.


Changes in version 0.2.3.15-alpha - 2012-04-30
  Tor 0.2.3.15-alpha fixes a variety of smaller bugs, including making
  the development branch build on Windows again.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Make sure that there are no unhandled pending TLS errors before
      reading from a TLS stream. We had checks in 0.1.0.3-rc, but
      lost them in 0.1.0.5-rc when we refactored read_to_buf_tls().
      Bugfix on 0.1.0.5-rc; fixes bug 4528.
    - Fix an assert that directory authorities could trigger on sighup
      during some configuration state transitions. We now don't treat
      it as a fatal error when the new descriptor we just generated in
      init_keys() isn't accepted. Fixes bug 4438; bugfix on 0.2.1.9-alpha.
    - After we pick a directory mirror, we would refuse to use it if
      it's in our ExcludeExitNodes list, resulting in mysterious failures
      to bootstrap for people who just wanted to avoid exiting from
      certain locations. Fixes bug 5623; bugfix on 0.2.2.25-alpha.
    - When building with --enable-static-tor on OpenBSD, do not
      erroneously attempt to link -lrt. Fixes bug 5103.

  o Minor bugfixes (on 0.2.3.x):
    - When Tor is built with kernel headers from a recent (last few
      years) Linux kernel, do not fail to run on older (pre-2.6.28
      Linux kernels). Fixes bug 5112; bugfix on 0.2.3.1-alpha.
    - Fix cross-compilation issues with mingw. Bugfixes on 0.2.3.6-alpha
      and 0.2.3.12-alpha.
    - Fix compilation with miniupnpc version 1.6; patch from
      Anthony G. Basile. Fixes bug 5434; bugfix on 0.2.3.12-alpha.
    - Fix compilation with MSVC, which had defined MS_WINDOWS. Bugfix
      on 0.2.3.13-alpha; found and fixed by Gisle Vanem.
    - Fix compilation on platforms without unistd.h, or where environ
      is defined in stdlib.h. Fixes bug 5704; bugfix on 0.2.3.13-alpha.

  o Minor features:
    - Directory authorities are now a little more lenient at accepting
      older router descriptors, or newer router descriptors that don't
      make big changes. This should help ameliorate past and future
      issues where routers think they have uploaded valid descriptors,
      but the authorities don't think so. Fix for ticket 2479.
    - Make the code that clients use to detect an address change be
      IPv6-aware, so that it won't fill clients' logs with error
      messages when trying to get the IPv4 address of an IPv6
      connection. Implements ticket 5537.

  o Removed features:
    - Remove the GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays option;
      authorities needed to use it for a while to keep the network working
      as people upgraded to 0.2.1.31, 0.2.2.34, or 0.2.3.6-alpha, but
      that was six months ago. As of now, it should no longer be needed
      or used.


Changes in version 0.2.3.14-alpha - 2012-04-23
  Tor 0.2.3.14-alpha fixes yet more bugs to get us closer to a release
  candidate. It also dramatically speeds up AES: fast relays should
  consider switching to the newer OpenSSL library.

  o Directory authority changes:
    - Change IP address for ides (v3 directory authority), and rename
      it to turtles.

  o Major bugfixes:
    - Avoid logging uninitialized data when unable to decode a hidden
      service descriptor cookie. Fixes bug 5647; bugfix on 0.2.1.5-alpha.
    - Avoid a client-side assertion failure when receiving an INTRODUCE2
      cell on a general purpose circuit. Fixes bug 5644; bugfix on
      0.2.1.6-alpha.
    - If authorities are unable to get a v2 consensus document from other
      directory authorities, they no longer fall back to fetching
      them from regular directory caches. Fixes bug 5635; bugfix on
      0.2.2.26-beta, where routers stopped downloading v2 consensus
      documents entirely.
    - When we start a Tor client with a normal consensus already cached,
      be willing to download a microdescriptor consensus. Fixes bug 4011;
      fix on 0.2.3.1-alpha.

  o Major features (performance):
    - When built to use OpenSSL 1.0.1, and built for an x86 or x86_64
      instruction set, take advantage of OpenSSL's AESNI, bitsliced, or
      vectorized AES implementations as appropriate. These can be much,
      much faster than other AES implementations.

  o Minor bugfixes (0.2.2.x and earlier):
    - Don't launch more than 10 service-side introduction-point circuits
      for a hidden service in five minutes. Previously, we would consider
      launching more introduction-point circuits if at least one second
      had passed without any introduction-point circuits failing. Fixes
      bug 4607; bugfix on 0.0.7pre1.
    - Change the BridgePassword feature (part of the "bridge community"
      design, which is not yet implemented) to use a time-independent
      comparison. The old behavior might have allowed an adversary
      to use timing to guess the BridgePassword value. Fixes bug 5543;
      bugfix on 0.2.0.14-alpha.
    - Enforce correct return behavior of tor_vsscanf() when the '%%'
      pattern is used. Fixes bug 5558. Bugfix on 0.2.1.13.
    - When sending an HTTP/1.1 proxy request, include a Host header.
      Fixes bug 5593; bugfix on 0.2.2.1-alpha.
    - Don't log that we have "decided to publish new relay descriptor"
      unless we are actually publishing a descriptor. Fixes bug 3942;
      bugfix on 0.2.2.28-beta.

  o Minor bugfixes (0.2.3.x):
    - Fix a bug where a bridge authority crashes (on a failed assert)
      if it has seen no directory requests when it's time to write
      statistics to disk. Fixes bug 5508. Bugfix on 0.2.3.6-alpha.
    - Fix bug stomping on ORPort option NoListen and ignoring option
      NoAdvertise. Fixes bug 5151; bugfix on 0.2.3.9-alpha.
    - In the testsuite, provide a large enough buffer in the tor_sscanf
      unit test. Otherwise we'd overrun that buffer and crash during
      the unit tests. Found by weasel. Fixes bug 5449; bugfix on
      0.2.3.12-alpha.
    - Make sure we create the keys directory if it doesn't exist and we're
      about to store the dynamic Diffie-Hellman parameters. Fixes bug
      5572; bugfix on 0.2.3.13-alpha.
    - Fix a small memory leak when trying to decode incorrect base16
      authenticator during SAFECOOKIE authentication. Found by
      Coverity Scan. Fixes CID 507. Bugfix on 0.2.3.13-alpha.

  o Minor features:
    - Add more information to a log statement that might help track down
      bug 4091. If you're seeing "Bug: tor_addr_is_internal() called with a
      non-IP address" messages (or any Bug messages, for that matter!),
      please let us know about it.
    - Relays now understand an IPv6 address when they get one from a
      directory server. Resolves ticket 4875.
    - Resolve IPv6 addresses in bridge and entry statistics to country
      code "??" which means we at least count them. Resolves ticket 5053;
      improves on 0.2.3.9-alpha.
    - Update to the April 3 2012 Maxmind GeoLite Country database.
    - Begin a doc/state-contents.txt file to explain the contents of
      the Tor state file. Fixes bug 2987.

  o Default torrc changes:
    - Stop listing "socksport 9050" in torrc.sample. We open a socks
      port on 9050 by default anyway, so this should not change anything
      in practice.
    - Stop mentioning the deprecated *ListenAddress options in
      torrc.sample. Fixes bug 5438.
    - Document unit of bandwidth related options in sample torrc.
      Fixes bug 5621.

  o Removed features:
    - The "torify" script no longer supports the "tsocks" socksifier
      tool, since tsocks doesn't support DNS and UDP right for Tor.
      Everyone should be using torsocks instead. Fixes bugs 3530 and
      5180. Based on a patch by "ugh".

  o Code refactoring:
    - Change the symmetric cipher interface so that creating and
      initializing a stream cipher are no longer separate functions.
    - Remove all internal support for unpadded RSA. We never used it, and
      it would be a bad idea to start.


Changes in version 0.2.3.13-alpha - 2012-03-26
  Tor 0.2.3.13-alpha fixes a variety of stability and correctness bugs
  in managed pluggable transports, as well as providing other cleanups
  that get us closer to a release candidate.

  o Directory authority changes:
    - Change IP address for maatuska (v3 directory authority).

  o Security fixes:
    - Provide controllers with a safer way to implement the cookie
      authentication mechanism. With the old method, if another locally
      running program could convince a controller that it was the Tor
      process, then that program could trick the controller into telling
      it the contents of an arbitrary 32-byte file. The new "SAFECOOKIE"
      authentication method uses a challenge-response approach to prevent
      this attack. Fixes bug 5185, implements proposal 193.
    - Never use a bridge or a controller-supplied node as an exit, even
      if its exit policy allows it. Found by wanoskarnet. Fixes bug
      5342. Bugfix on 0.1.1.15-rc (for controller-purpose descriptors)
      and 0.2.0.3-alpha (for bridge-purpose descriptors).
    - Only build circuits if we have a sufficient threshold of the total
      descriptors that are marked in the consensus with the "Exit"
      flag. This mitigates an attack proposed by wanoskarnet, in which
      all of a client's bridges collude to restrict the exit nodes that
      the client knows about. Fixes bug 5343.

  o Major bugfixes (on Tor 0.2.3.x):
    - Avoid an assert when managed proxies like obfsproxy are configured,
      and we receive HUP signals or setconf attempts too rapidly. This
      situation happens most commonly when Vidalia tries to attach to
      Tor or tries to configure the Tor it's attached to. Fixes bug 5084;
      bugfix on 0.2.3.6-alpha.
    - Fix a relay-side pluggable transports bug where managed proxies were
      unreachable from the Internet, because Tor asked them to bind on
      localhost. Fixes bug 4725; bugfix on 0.2.3.9-alpha.
    - Stop discarding command-line arguments when TestingTorNetwork
      is set. Discovered by Kevin Bauer. Fixes bug 5373; bugfix on
      0.2.3.9-alpha, where task 4552 added support for two layers of
      torrc files.
    - Resume allowing the unit tests to run in gdb. This was accidentally
      made impossible when the DisableDebuggerAttachment option was
      introduced. Fixes bug 5448; bugfix on 0.2.3.9-alpha.
    - Resume building with nat-pmp support. Fixes bug 4955; bugfix on
      0.2.3.11-alpha. Reported by Anthony G. Basile.

  o Minor bugfixes (on 0.2.2.x and earlier):
    - Ensure we don't cannibalize circuits that are longer than three hops
      already, so we don't end up making circuits with 5 or more
      hops. Patch contributed by wanoskarnet. Fixes bug 5231; bugfix on
      0.1.0.1-rc which introduced cannibalization.
    - Detect and reject certain misformed escape sequences in
      configuration values. Previously, these values would cause us
      to crash if received in a torrc file or over an authenticated
      control port. Bug found by Esteban Manchado Velázquez, and
      independently by Robert Connolly from Matta Consulting who further
      noted that it allows a post-authentication heap overflow. Patch
      by Alexander Schrijver. Fixes bugs 5090 and 5402 (CVE 2012-1668);
      bugfix on 0.2.0.16-alpha.
    - Fix a compile warning when using the --enable-openbsd-malloc
      configure option. Fixes bug 5340; bugfix on 0.2.0.20-rc.
    - Directory caches no longer refuse to clean out descriptors because
      of missing v2 networkstatus documents, unless they're configured
      to retrieve v2 networkstatus documents. Fixes bug 4838; bugfix on
      0.2.2.26-beta. Patch by Daniel Bryg.
    - Update to the latest version of the tinytest unit testing framework.
      This includes a couple of bugfixes that can be relevant for
      running forked unit tests on Windows, and removes all reserved
      identifiers.

  o Minor bugfixes (on 0.2.3.x):
    - On a failed pipe() call, don't leak file descriptors. Fixes bug
      4296; bugfix on 0.2.3.1-alpha.
    - Spec conformance: on a v3 handshake, do not send a NETINFO cell
      until after we have received a CERTS cell. Fixes bug 4361; bugfix
      on 0.2.3.6-alpha. Patch by "frosty".
    - When binding to an IPv6 address, set the IPV6_V6ONLY socket
      option, so that the IP stack doesn't decide to use it for IPv4
      too. Fixes bug 4760; bugfix on 0.2.3.9-alpha.
    - Ensure that variables set in Tor's environment cannot override
      environment variables that Tor passes to a managed
      pluggable-transport proxy. Previously, Tor would pass every
      variable in its environment to managed proxies along with the new
      ones, in such a way that on many operating systems, the inherited
      environment variables would override those which Tor tried to
      explicitly set. Bugfix on 0.2.3.12-alpha for most Unixoid systems;
      bugfix on 0.2.3.9-alpha for Windows.

  o Minor features:
    - A wide variety of new unit tests by Esteban Manchado Velázquez.
    - Shorten links in the tor-exit-notice file. Patch by Christian Kujau.
    - Update to the March 6 2012 Maxmind GeoLite Country database.


Changes in version 0.2.3.12-alpha - 2012-02-13
  Tor 0.2.3.12-alpha lets fast exit relays scale better, allows clients
  to use bridges that run Tor 0.2.2.x, and resolves several big bugs
  when Tor is configured to use a pluggable transport like obfsproxy.

  o Major bugfixes:
    - Fix builds when the path to sed, openssl, or sha1sum contains
      spaces, which is pretty common on Windows. Fixes bug 5065; bugfix
      on 0.2.2.1-alpha.
    - Set the SO_REUSEADDR socket option before we call bind() on outgoing
      connections. This change should allow busy exit relays to stop
      running out of available sockets as quickly. Fixes bug 4950;
      bugfix on 0.2.2.26-beta.
    - Allow 0.2.3.x clients to use 0.2.2.x bridges. Previously the client
      would ask the bridge for microdescriptors, which are only supported
      in 0.2.3.x, and then fail to bootstrap when it didn't get the
      answers it wanted. Fixes bug 4013; bugfix on 0.2.3.2-alpha.
    - Properly set up obfsproxy's environment when in managed mode. The
      Tor Browser Bundle needs LD_LIBRARY_PATH to be passed to obfsproxy,
      and when you run your Tor as a daemon, there's no HOME. Fixes bugs
      5076 and 5082; bugfix on 0.2.3.6-alpha.

  o Minor features:
    - Use the dead_strip option when building Tor on OS X. This reduces
      binary size by almost 19% when linking openssl and libevent
      statically, which we do for Tor Browser Bundle.
    - Fix broken URLs in the sample torrc file, and tell readers about
      the OutboundBindAddress, ExitPolicyRejectPrivate, and
      PublishServerDescriptor options. Addresses bug 4652.
    - Update to the February 7 2012 Maxmind GeoLite Country database.

  o Minor bugfixes:
    - Downgrade the "We're missing a certificate" message from notice
      to info: people kept mistaking it for a real problem, whereas it
      is seldom the problem even when we are failing to bootstrap. Fixes
      bug 5067; bugfix on 0.2.0.10-alpha.
    - Don't put "TOR_PT_EXTENDED_SERVER_PORT=127.0.0.1:4200" in a
      managed pluggable transport server proxy's environment.
      Previously, we would put it there, even though Tor doesn't
      implement an 'extended server port' yet, and even though Tor
      almost certainly isn't listening at that address. For now, we set
      it to an empty string to avoid crashing older obfsproxies. Bugfix
      on 0.2.3.6-alpha.
    - Log the heartbeat message every HeartbeatPeriod seconds, not every
      HeartbeatPeriod + 1 seconds. Fixes bug 4942; bugfix on
      0.2.3.1-alpha. Bug reported by Scott Bennett.
    - Calculate absolute paths correctly on Windows. Fixes bug 4973;
      bugfix on 0.2.3.11-alpha.
    - Update "ClientOnly" man page entry to explain that there isn't
      really any point to messing with it. Resolves ticket 5005.
    - Use the correct CVE number for CVE-2011-4576 in our comments and
      log messages. Found by "fermenthor". Resolves bug 5066; bugfix on
      0.2.3.11-alpha.

  o Code simplifications and refactoring:
    - Use the _WIN32 macro throughout our code to detect Windows.
      (Previously we had used the obsolete 'WIN32' and the idiosyncratic
      'MS_WINDOWS'.)


Changes in version 0.2.3.11-alpha - 2012-01-22
  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.

  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