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+Changes in version 0.3.3.3-alpha - 2018-03-03
+  Tor 0.3.3.3-alpha is the third alpha release for the 0.3.3.x series.
+  It includes an important security fix for a remote crash attack
+  against directory authorities tracked as TROVE-2018-001.
+
+  Additionally, with this release, we are upgrading the severity of a
+  bug fixed in 0.3.3.2-alpha.  Bug 24700, which was fixed in
+  0.3.3.2-alpha, can be remotely triggered in order to crash relays with
+  a use-after-free pattern. As such, we are now tracking that bug as
+  TROVE-2018-002 and CVE-2018-0491. This bug affected versions
+  0.3.2.1-alpha through 0.3.2.9, as well as 0.3.3.1-alpha.
+
+  This release also fixes several minor bugs and annoyances from
+  earlier releases.
+
+  Relays running 0.3.2.x should upgrade to one of the versions released
+  today, for the fix to TROVE-2018-002.  Directory authorities should
+  also upgrade. (Relays on earlier versions might want to update too for
+  the DoS mitigations.)
+
+  o Major bugfixes (denial-of-service, directory authority):
+    - Fix a protocol-list handling bug that could be used to remotely crash
+      directory authorities with a null-pointer exception. Fixes bug 25074;
+      bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and
+      CVE-2018-0490.
+
+  o Minor features (compatibility, OpenSSL):
+    - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released.
+      Previous versions of Tor would not have worked with OpenSSL 1.1.1,
+      since they neither disabled TLS 1.3 nor enabled any of the
+      ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites.
+      Closes ticket 24978.
+
+  o Minor features (logging):
+    - Clarify the log messages produced when getrandom() or a related
+      entropy-generation mechanism gives an error. Closes ticket 25120.
+
+  o Minor features (testing):
+    - Add a "make test-rust" target to run the rust tests only. Closes
+      ticket 25071.
+
+  o Minor bugfixes (denial-of-service):
+    - Fix a possible crash on malformed consensus. If a consensus had
+      contained an unparseable protocol line, it could have made clients
+      and relays crash with a null-pointer exception. To exploit this
+      issue, however, an attacker would need to be able to subvert the
+      directory authority system. Fixes bug 25251; bugfix on
+      0.2.9.4-alpha. Also tracked as TROVE-2018-004.
+
+  o Minor bugfixes (DoS mitigation):
+    - Add extra safety checks when refilling the circuit creation bucket
+      to ensure we never set a value above the allowed maximum burst.
+      Fixes bug 25202; bugfix on 0.3.3.2-alpha.
+    - When a new consensus arrives, don't update our DoS-mitigation
+      parameters if we aren't a public relay. Fixes bug 25223; bugfix
+      on 0.3.3.2-alpha.
+
+  o Minor bugfixes (man page, SocksPort):
+    - Remove dead code from the old "SocksSocket" option, and rename
+      SocksSocketsGroupWritable to UnixSocksGroupWritable. The old option
+      still works, but is deprecated. Fixes bug 24343; bugfix on 0.2.6.3.
+
+  o Minor bugfixes (performance):
+    - Reduce the number of circuits that will be opened at once during
+      the circuit build timeout phase. This is done by increasing the
+      idle timeout to 3 minutes, and lowering the maximum number of
+      concurrent learning circuits to 10. Fixes bug 24769; bugfix
+      on 0.3.1.1-alpha.
+
+  o Minor bugfixes (spec conformance):
+    - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on
+      0.2.9.4-alpha.
+    - Forbid UINT32_MAX as a protocol version.  Fixes part of bug 25249;
+      bugfix on 0.2.9.4-alpha.
+
+  o Minor bugfixes (spec conformance, rust):
+    - Resolve a denial-of-service issue caused by an infinite loop in
+      the rust protover code. Fixes bug 25250, bugfix on 0.3.3.1-alpha.
+      Also tracked as TROVE-2018-003.
+
+  o Code simplification and refactoring:
+    - Update the "rust dependencies" submodule to be a project-level
+      repository, rather than a user repository. Closes ticket 25323.
+
+
+Changes in version 0.3.2.10 - 2018-03-03
+  Tor 0.3.2.10 is the second stable release in the 0.3.2 series. It
+  backports a number of bugfixes, including important fixes for security
+  issues.
+
+  It includes an important security fix for a remote crash attack
+  against directory authorities, tracked as TROVE-2018-001.
+
+  Additionally, it backports a fix for a bug whose severity we have
+  upgraded: Bug 24700, which was fixed in 0.3.3.2-alpha, can be remotely
+  triggered in order to crash relays with a use-after-free pattern. As
+  such, we are now tracking that bug as TROVE-2018-002 and
+  CVE-2018-0491, and backporting it to earlier releases.  This bug
+  affected versions 0.3.2.1-alpha through 0.3.2.9, as well as version
+  0.3.3.1-alpha.
+
+  This release also backports our new system for improved resistance to
+  denial-of-service attacks against relays.
+
+  This release also fixes several minor bugs and annoyances from
+  earlier releases.
+
+  Relays running 0.3.2.x SHOULD upgrade to one of the versions released
+  today, for the fix to TROVE-2018-002.  Directory authorities should
+  also upgrade. (Relays on earlier versions might want to update too for
+  the DoS mitigations.)
+
+  o Major bugfixes (denial-of-service, directory authority, backport from 0.3.3.3-alpha):
+    - Fix a protocol-list handling bug that could be used to remotely crash
+      directory authorities with a null-pointer exception. Fixes bug 25074;
+      bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and
+      CVE-2018-0490.
+
+  o Major bugfixes (scheduler, KIST, denial-of-service, backport from 0.3.3.2-alpha):
+    - Avoid adding the same channel twice in the KIST scheduler pending
+      list, which could lead to remote denial-of-service use-after-free
+      attacks against relays. Fixes bug 24700; bugfix on 0.3.2.1-alpha.
+
+  o Major features (denial-of-service mitigation, backport from 0.3.3.2-alpha):
+    - Give relays some defenses against the recent network overload. We
+      start with three defenses (default parameters in parentheses).
+      First: if a single client address makes too many concurrent
+      connections (>100), hang up on further connections. Second: if a
+      single client address makes circuits too quickly (more than 3 per
+      second, with an allowed burst of 90) while also having too many
+      connections open (3), refuse new create cells for the next while
+      (1-2 hours). Third: if a client asks to establish a rendezvous
+      point to you directly, ignore the request. These defenses can be
+      manually controlled by new torrc options, but relays will also
+      take guidance from consensus parameters, so there's no need to
+      configure anything manually. Implements ticket 24902.
+
+  o Major bugfixes (onion services, retry behavior, backport from 0.3.3.1-alpha):
+    - Fix an "off by 2" error in counting rendezvous failures on the
+      onion service side. While we thought we would stop the rendezvous
+      attempt after one failed circuit, we were actually making three
+      circuit attempts before giving up. Now switch to a default of 2,
+      and allow the consensus parameter "hs_service_max_rdv_failures" to
+      override. Fixes bug 24895; bugfix on 0.0.6.
+    - New-style (v3) onion services now obey the "max rendezvous circuit
+      attempts" logic. Previously they would make as many rendezvous
+      circuit attempts as they could fit in the MAX_REND_TIMEOUT second
+      window before giving up. Fixes bug 24894; bugfix on 0.3.2.1-alpha.
+
+  o Major bugfixes (protocol versions, backport from 0.3.3.2-alpha):
+    - Add Link protocol version 5 to the supported protocols list. Fixes
+      bug 25070; bugfix on 0.3.1.1-alpha.
+
+  o Major bugfixes (relay, backport from 0.3.3.1-alpha):
+    - Fix a set of false positives where relays would consider
+      connections to other relays as being client-only connections (and
+      thus e.g. deserving different link padding schemes) if those
+      relays fell out of the consensus briefly. Now we look only at the
+      initial handshake and whether the connection authenticated as a
+      relay. Fixes bug 24898; bugfix on 0.3.1.1-alpha.
+
+  o Major bugfixes (scheduler, consensus, backport from 0.3.3.2-alpha):
+    - The scheduler subsystem was failing to promptly notice changes in
+      consensus parameters, making it harder to switch schedulers
+      network-wide. Fixes bug 24975; bugfix on 0.3.2.1-alpha.
+
+  o Minor features (denial-of-service avoidance, backport from 0.3.3.2-alpha):
+    - Make our OOM handler aware of the geoip client history cache so it
+      doesn't fill up the memory. This check is important for IPv6 and
+      our DoS mitigation subsystem. Closes ticket 25122.
+
+  o Minor features (compatibility, OpenSSL, backport from 0.3.3.3-alpha):
+    - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released.
+      Previous versions of Tor would not have worked with OpenSSL 1.1.1,
+      since they neither disabled TLS 1.3 nor enabled any of the
+      ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites.
+      Closes ticket 24978.
+
+  o Minor features (geoip):
+    - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2
+      Country database.
+
+  o Minor features (logging, diagnostic, backport from 0.3.3.2-alpha):
+    - When logging a failure to check a hidden service's certificate,
+      also log what the problem with the certificate was. Diagnostic
+      for ticket 24972.
+
+  o Minor bugfix (channel connection, backport from 0.3.3.2-alpha):
+    - Use the actual observed address of an incoming relay connection,
+      not the canonical address of the relay from its descriptor, when
+      making decisions about how to handle the incoming connection.
+      Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera".
+
+  o Minor bugfixes (denial-of-service, backport from 0.3.3.3-alpha):
+    - Fix a possible crash on malformed consensus. If a consensus had
+      contained an unparseable protocol line, it could have made clients
+      and relays crash with a null-pointer exception. To exploit this
+      issue, however, an attacker would need to be able to subvert the
+      directory authority system. Fixes bug 25251; bugfix on
+      0.2.9.4-alpha. Also tracked as TROVE-2018-004.
+
+  o Minor bugfix (directory authority, backport from 0.3.3.2-alpha):
+    - Directory authorities, when refusing a descriptor from a rejected
+      relay, now explicitly tell the relay (in its logs) to set a valid
+      ContactInfo address and contact the bad-relays@ mailing list.
+      Fixes bug 25170; bugfix on 0.2.9.1.
+
+  o Minor bugfixes (build, rust, backport from 0.3.3.1-alpha):
+    - When building with Rust on OSX, link against libresolv, to work
+      around the issue at https://github.com/rust-lang/rust/issues/46797.
+      Fixes bug 24652; bugfix on 0.3.1.1-alpha.
+
+  o Minor bugfixes (onion services, backport from 0.3.3.2-alpha):
+    - Remove a BUG() statement when a client fetches an onion descriptor
+      that has a lower revision counter than the one in its cache. This
+      can happen in normal circumstances due to HSDir desync. Fixes bug
+      24976; bugfix on 0.3.2.1-alpha.
+
+  o Minor bugfixes (logging, backport from 0.3.3.2-alpha):
+    - Don't treat inability to store a cached consensus object as a bug:
+      it can happen normally when we are out of disk space. Fixes bug
+      24859; bugfix on 0.3.1.1-alpha.
+
+  o Minor bugfixes (performance, fragile-hardening, backport from 0.3.3.1-alpha):
+    - Improve the performance of our consensus-diff application code
+      when Tor is built with the --enable-fragile-hardening option set.
+      Fixes bug 24826; bugfix on 0.3.1.1-alpha.
+
+  o Minor bugfixes (OSX, backport from 0.3.3.1-alpha):
+    - Don't exit the Tor process if setrlimit() fails to change the file
+      limit (which can happen sometimes on some versions of OSX). Fixes
+      bug 21074; bugfix on 0.0.9pre5.
+
+  o Minor bugfixes (spec conformance, backport from 0.3.3.3-alpha):
+    - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on
+      0.2.9.4-alpha.
+    - Forbid UINT32_MAX as a protocol version.  Fixes part of bug 25249;
+      bugfix on 0.2.9.4-alpha.
+
+  o Minor bugfixes (testing, backport from 0.3.3.1-alpha):
+    - Fix a memory leak in the scheduler/loop_kist unit test. Fixes bug
+      25005; bugfix on 0.3.2.7-rc.
+
+  o Minor bugfixes (v3 onion services, backport from 0.3.3.2-alpha):
+    - Look at the "HSRend" protocol version, not the "HSDir" protocol
+      version, when deciding whether a consensus entry can support the
+      v3 onion service protocol as a rendezvous point. Fixes bug 25105;
+      bugfix on 0.3.2.1-alpha.
+
+  o Code simplification and refactoring (backport from 0.3.3.3-alpha):
+    - Update the "rust dependencies" submodule to be a project-level
+      repository, rather than a user repository. Closes ticket 25323.
+
+  o Documentation (backport from 0.3.3.1-alpha)
+    - Document that operators who run more than one relay or bridge are
+      expected to set MyFamily and ContactInfo correctly. Closes
+      ticket 24526.
+
+
+Changes in version 0.3.1.10 - 2018-03-03
+  Tor 0.3.1.10 backports a number of bugfixes, including important fixes for
+  security issues.
+
+  It includes an important security fix for a remote crash attack
+  against directory authorities, tracked as TROVE-2018-001.
+
+  This release also backports our new system for improved resistance to
+  denial-of-service attacks against relays.
+
+  This release also fixes several minor bugs and annoyances from
+  earlier releases.
+
+  All directory authorities should upgrade to one of the versions
+  released today.  Relays running 0.3.1.x may wish to update to one of
+  the versions released today, for the DoS mitigations.
+
+  Please note: according to our release calendar, Tor 0.3.1 will no
+  longer be supported after 1 July 2018.  If you will be running Tor
+  after that date, you should make sure to plan to upgrade to the latest
+  stable version, or downgrade to 0.2.9 (which will receive long-term
+  support).
+
+  o Major bugfixes (denial-of-service, directory authority, backport from 0.3.3.3-alpha):
+    - Fix a protocol-list handling bug that could be used to remotely crash
+      directory authorities with a null-pointer exception. Fixes bug 25074;
+      bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and
+      CVE-2018-0490.
+
+  o Major features (denial-of-service mitigation, backport from 0.3.3.2-alpha):
+    - Give relays some defenses against the recent network overload. We
+      start with three defenses (default parameters in parentheses).
+      First: if a single client address makes too many concurrent
+      connections (>100), hang up on further connections. Second: if a
+      single client address makes circuits too quickly (more than 3 per
+      second, with an allowed burst of 90) while also having too many
+      connections open (3), refuse new create cells for the next while
+      (1-2 hours). Third: if a client asks to establish a rendezvous
+      point to you directly, ignore the request. These defenses can be
+      manually controlled by new torrc options, but relays will also
+      take guidance from consensus parameters, so there's no need to
+      configure anything manually. Implements ticket 24902.
+
+  o Minor features (linux seccomp2 sandbox, backport from 0.3.2.5-alpha):
+    - Update the sandbox rules so that they should now work correctly
+      with Glibc 2.26. Closes ticket 24315.
+
+  o Major bugfixes (onion services, retry behavior, backport from 0.3.3.1-alpha):
+    - Fix an "off by 2" error in counting rendezvous failures on the
+      onion service side. While we thought we would stop the rendezvous
+      attempt after one failed circuit, we were actually making three
+      circuit attempts before giving up. Now switch to a default of 2,
+      and allow the consensus parameter "hs_service_max_rdv_failures" to
+      override. Fixes bug 24895; bugfix on 0.0.6.
+
+  o Major bugfixes (protocol versions, backport from 0.3.3.2-alpha):
+    - Add Link protocol version 5 to the supported protocols list. Fixes
+      bug 25070; bugfix on 0.3.1.1-alpha.
+
+  o Major bugfixes (relay, backport from 0.3.3.1-alpha):
+    - Fix a set of false positives where relays would consider
+      connections to other relays as being client-only connections (and
+      thus e.g. deserving different link padding schemes) if those
+      relays fell out of the consensus briefly. Now we look only at the
+      initial handshake and whether the connection authenticated as a
+      relay. Fixes bug 24898; bugfix on 0.3.1.1-alpha.
+
+  o Minor features (denial-of-service avoidance, backport from 0.3.3.2-alpha):
+    - Make our OOM handler aware of the geoip client history cache so it
+      doesn't fill up the memory. This check is important for IPv6 and
+      our DoS mitigation subsystem. Closes ticket 25122.
+
+  o Minor feature (relay statistics, backport from 0.3.2.6-alpha):
+    - Change relay bandwidth reporting stats interval from 4 hours to 24
+      hours in order to reduce the efficiency of guard discovery
+      attacks. Fixes ticket 23856.
+
+  o Minor features (compatibility, OpenSSL, backport from 0.3.3.3-alpha):
+    - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released.
+      Previous versions of Tor would not have worked with OpenSSL 1.1.1,
+      since they neither disabled TLS 1.3 nor enabled any of the
+      ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites.
+      Closes ticket 24978.
+
+  o Minor features (fallback directory mirrors, backport from 0.3.2.9):
+    - The fallback directory list has been re-generated based on the
+      current status of the network. Tor uses fallback directories to
+      bootstrap when it doesn't yet have up-to-date directory
+      information. Closes ticket 24801.
+    - Make the default DirAuthorityFallbackRate 0.1, so that clients
+      prefer to bootstrap from fallback directory mirrors. This is a
+      follow-up to 24679, which removed weights from the default
+      fallbacks. Implements ticket 24681.
+
+  o Minor features (geoip):
+    - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2
+      Country database.
+
+  o Minor bugfix (channel connection, backport from 0.3.3.2-alpha):
+    - Use the actual observed address of an incoming relay connection,
+      not the canonical address of the relay from its descriptor, when
+      making decisions about how to handle the incoming connection.
+      Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera".
+
+  o Minor bugfix (directory authority, backport from 0.3.3.2-alpha):
+    - Directory authorities, when refusing a descriptor from a rejected
+      relay, now explicitly tell the relay (in its logs) to set a valid
+      ContactInfo address and contact the bad-relays@ mailing list.
+      Fixes bug 25170; bugfix on 0.2.9.1.
+
+  o Minor bugfixes (address selection, backport from 0.3.2.9):
+    - When the fascist_firewall_choose_address_ functions don't find a
+      reachable address, set the returned address to the null address
+      and port. This is a precautionary measure, because some callers do
+      not check the return value. Fixes bug 24736; bugfix
+      on 0.2.8.2-alpha.
+
+  o Major bugfixes (bootstrapping, backport from 0.3.2.5-alpha):
+    - Fetch descriptors aggressively whenever we lack enough to build
+      circuits, regardless of how many descriptors we are missing.
+      Previously, we would delay launching the fetch when we had fewer
+      than 15 missing descriptors, even if some of those descriptors
+      were blocking circuits from building. Fixes bug 23985; bugfix on
+      0.1.1.11-alpha. The effects of this bug became worse in
+      0.3.0.3-alpha, when we began treating missing descriptors from our
+      primary guards as a reason to delay circuits.
+    - Don't try fetching microdescriptors from relays that have failed
+      to deliver them in the past. Fixes bug 23817; bugfix
+      on 0.3.0.1-alpha.
+
+  o Minor bugfixes (compilation, backport from 0.3.2.7-rc):
+    - Fix a signed/unsigned comparison warning introduced by our fix to
+      TROVE-2017-009. Fixes bug 24480; bugfix on 0.2.5.16.
+
+  o Minor bugfixes (control port, linux seccomp2 sandbox, backport from 0.3.2.5-alpha):
+    - Avoid a crash when attempting to use the seccomp2 sandbox together
+      with the OwningControllerProcess feature. Fixes bug 24198; bugfix
+      on 0.2.5.1-alpha.
+
+  o Minor bugfixes (denial-of-service, backport from 0.3.3.3-alpha):
+    - Fix a possible crash on malformed consensus. If a consensus had
+      contained an unparseable protocol line, it could have made clients
+      and relays crash with a null-pointer exception. To exploit this
+      issue, however, an attacker would need to be able to subvert the
+      directory authority system. Fixes bug 25251; bugfix on
+      0.2.9.4-alpha. Also tracked as TROVE-2018-004.
+
+  o Minor bugfixes (directory cache, backport from 0.3.2.5-alpha):
+    - Recover better from empty or corrupt files in the consensus cache
+      directory. Fixes bug 24099; bugfix on 0.3.1.1-alpha.
+    - When a consensus diff calculation is only partially successful,
+      only record the successful parts as having succeeded. Partial
+      success can happen if (for example) one compression method fails
+      but the others succeed. Previously we misrecorded all the
+      calculations as having succeeded, which would later cause a
+      nonfatal assertion failure. Fixes bug 24086; bugfix
+      on 0.3.1.1-alpha.
+
+  o Minor bugfixes (entry guards, backport from 0.3.2.3-alpha):
+    - Tor now updates its guard state when it reads a consensus
+      regardless of whether it's missing descriptors. That makes tor use
+      its primary guards to fetch descriptors in some edge cases where
+      it would previously have used fallback directories. Fixes bug
+      23862; bugfix on 0.3.0.1-alpha.
+
+  o Minor bugfixes (logging, backport from 0.3.3.2-alpha):
+    - Don't treat inability to store a cached consensus object as a bug:
+      it can happen normally when we are out of disk space. Fixes bug
+      24859; bugfix on 0.3.1.1-alpha.
+
+  o Minor bugfixes (memory usage, backport from 0.3.2.8-rc):
+    - When queuing DESTROY cells on a channel, only queue the circuit-id
+      and reason fields: not the entire 514-byte cell. This fix should
+      help mitigate any bugs or attacks that fill up these queues, and
+      free more RAM for other uses. Fixes bug 24666; bugfix
+      on 0.2.5.1-alpha.
+
+  o Minor bugfixes (network layer, backport from 0.3.2.5-alpha):
+    - When closing a connection via close_connection_immediately(), we
+      mark it as "not blocked on bandwidth", to prevent later calls from
+      trying to unblock it, and give it permission to read. This fixes a
+      backtrace warning that can happen on relays under various
+      circumstances. Fixes bug 24167; bugfix on 0.1.0.1-rc.
+
+  o Minor bugfixes (path selection, backport from 0.3.2.4-alpha):
+    - When selecting relays by bandwidth, avoid a rounding error that
+      could sometimes cause load to be imbalanced incorrectly.
+      Previously, we would always round upwards; now, we round towards
+      the nearest integer. This had the biggest effect when a relay's
+      weight adjustments should have given it weight 0, but it got
+      weight 1 instead. Fixes bug 23318; bugfix on 0.2.4.3-alpha.
+    - When calculating the fraction of nodes that have descriptors, and
+      all nodes in the network have zero bandwidths, count the number of
+      nodes instead. Fixes bug 23318; bugfix on 0.2.4.10-alpha.
+    - Actually log the total bandwidth in compute_weighted_bandwidths().
+      Fixes bug 24170; bugfix on 0.2.4.3-alpha.
+
+  o Minor bugfixes (performance, fragile-hardening, backport from 0.3.3.1-alpha):
+    - Improve the performance of our consensus-diff application code
+      when Tor is built with the --enable-fragile-hardening option set.
+      Fixes bug 24826; bugfix on 0.3.1.1-alpha.
+
+  o Minor bugfixes (OSX, backport from 0.3.3.1-alpha):
+    - Don't exit the Tor process if setrlimit() fails to change the file
+      limit (which can happen sometimes on some versions of OSX). Fixes
+      bug 21074; bugfix on 0.0.9pre5.
+
+  o Minor bugfixes (portability, msvc, backport from 0.3.2.9):
+    - Fix a bug in the bit-counting parts of our timing-wheel code on
+      MSVC. (Note that MSVC is still not a supported build platform, due
+      to cyptographic timing channel risks.) Fixes bug 24633; bugfix
+      on 0.2.9.1-alpha.
+
+  o Minor bugfixes (relay, partial backport):
+    - Make the internal channel_is_client() function look at what sort
+      of connection handshake the other side used, rather than whether
+      the other side ever sent a create_fast cell to us. Backports part
+      of the fixes from bugs 22805 and 24898.
+
+  o Minor bugfixes (spec conformance, backport from 0.3.3.3-alpha):
+    - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on
+      0.2.9.4-alpha.
+    - Forbid UINT32_MAX as a protocol version.  Fixes part of bug 25249;
+      bugfix on 0.2.9.4-alpha.
+
+  o Code simplification and refactoring (backport from 0.3.3.3-alpha):
+    - Update the "rust dependencies" submodule to be a project-level
+      repository, rather than a user repository. Closes ticket 25323.
+
+
+Changes in version 0.2.9.15 - 2018-03-03
+  Tor 0.2.9.15 backports important security and stability bugfixes from
+  later Tor releases.
+
+  It includes an important security fix for a remote crash attack
+  against directory authorities, tracked as TROVE-2018-001.
+
+  This release also backports our new system for improved resistance to
+  denial-of-service attacks against relays.
+
+  This release also fixes several minor bugs and annoyances from
+  earlier releases.
+
+  All directory authorities should upgrade to one of the versions
+  released today.  Relays running 0.2.9.x may wish to update to one of
+  the versions released today, for the DoS mitigations.
+
+  o Major bugfixes (denial-of-service, directory authority, backport from 0.3.3.3-alpha):
+    - Fix a protocol-list handling bug that could be used to remotely crash
+      directory authorities with a null-pointer exception. Fixes bug 25074;
+      bugfix on 0.2.9.4-alpha. Also tracked as TROVE-2018-001 and
+      CVE-2018-0490.
+
+  o Major features (denial-of-service mitigation):
+    - Give relays some defenses against the recent network overload. We
+      start with three defenses (default parameters in parentheses).
+      First: if a single client address makes too many concurrent
+      connections (>100), hang up on further connections. Second: if a
+      single client address makes circuits too quickly (more than 3 per
+      second, with an allowed burst of 90) while also having too many
+      connections open (3), refuse new create cells for the next while
+      (1-2 hours). Third: if a client asks to establish a rendezvous
+      point to you directly, ignore the request. These defenses can be
+      manually controlled by new torrc options, but relays will also
+      take guidance from consensus parameters, so there's no need to
+      configure anything manually. Implements ticket 24902.
+
+  o Major bugfixes (bootstrapping):
+    - Fetch descriptors aggressively whenever we lack enough to build
+      circuits, regardless of how many descriptors we are missing.
+      Previously, we would delay launching the fetch when we had fewer
+      than 15 missing descriptors, even if some of those descriptors
+      were blocking circuits from building. Fixes bug 23985; bugfix on
+      0.1.1.11-alpha. The effects of this bug became worse in
+      0.3.0.3-alpha, when we began treating missing descriptors from our
+      primary guards as a reason to delay circuits.
+
+  o Major bugfixes (onion services, retry behavior):
+    - Fix an "off by 2" error in counting rendezvous failures on the
+      onion service side. While we thought we would stop the rendezvous
+      attempt after one failed circuit, we were actually making three
+      circuit attempts before giving up. Now switch to a default of 2,
+      and allow the consensus parameter "hs_service_max_rdv_failures" to
+      override. Fixes bug 24895; bugfix on 0.0.6.
+
+  o Minor feature (relay statistics):
+    - Change relay bandwidth reporting stats interval from 4 hours to 24
+      hours in order to reduce the efficiency of guard discovery
+      attacks. Fixes ticket 23856.
+
+  o Minor features (compatibility, OpenSSL):
+    - Tor will now support TLS1.3 once OpenSSL 1.1.1 is released.
+      Previous versions of Tor would not have worked with OpenSSL 1.1.1,
+      since they neither disabled TLS 1.3 nor enabled any of the
+      ciphersuites it requires. Now we enable the TLS 1.3 ciphersuites.
+      Closes ticket 24978.
+
+  o Minor features (denial-of-service avoidance):
+    - Make our OOM handler aware of the geoip client history cache so it
+      doesn't fill up the memory. This check is important for IPv6 and
+      our DoS mitigation subsystem. Closes ticket 25122.
+
+  o Minor features (fallback directory mirrors):
+    - The fallback directory list has been re-generated based on the
+      current status of the network. Tor uses fallback directories to
+      bootstrap when it doesn't yet have up-to-date directory
+      information. Closes ticket 24801.
+    - Make the default DirAuthorityFallbackRate 0.1, so that clients
+      prefer to bootstrap from fallback directory mirrors. This is a
+      follow-up to 24679, which removed weights from the default
+      fallbacks. Implements ticket 24681.
+
+  o Minor features (geoip):
+    - Update geoip and geoip6 to the February 7 2018 Maxmind GeoLite2
+      Country database.
+
+  o Minor features (linux seccomp2 sandbox):
+    - Update the sandbox rules so that they should now work correctly
+      with Glibc 2.26. Closes ticket 24315.
+
+  o Minor bugfix (channel connection):
+    - Use the actual observed address of an incoming relay connection,
+      not the canonical address of the relay from its descriptor, when
+      making decisions about how to handle the incoming connection.
+      Fixes bug 24952; bugfix on 0.2.4.11-alpha. Patch by "ffmancera".
+
+  o Minor bugfix (directory authority):
+    - Directory authorities, when refusing a descriptor from a rejected
+      relay, now explicitly tell the relay (in its logs) to set a valid
+      ContactInfo address and contact the bad-relays@ mailing list.
+      Fixes bug 25170; bugfix on 0.2.9.1.
+
+  o Minor bugfixes (address selection):
+    - When the fascist_firewall_choose_address_ functions don't find a
+      reachable address, set the returned address to the null address
+      and port. This is a precautionary measure, because some callers do
+      not check the return value. Fixes bug 24736; bugfix
+      on 0.2.8.2-alpha.
+
+  o Minor bugfixes (compilation):
+    - Fix a signed/unsigned comparison warning introduced by our fix to
+      TROVE-2017-009. Fixes bug 24480; bugfix on 0.2.5.16.
+
+  o Minor bugfixes (control port, linux seccomp2 sandbox):
+    - Avoid a crash when attempting to use the seccomp2 sandbox together
+      with the OwningControllerProcess feature. Fixes bug 24198; bugfix
+      on 0.2.5.1-alpha.
+
+  o Minor bugfixes (denial-of-service, backport from 0.3.3.3-alpha):
+    - Fix a possible crash on malformed consensus. If a consensus had
+      contained an unparseable protocol line, it could have made clients
+      and relays crash with a null-pointer exception. To exploit this
+      issue, however, an attacker would need to be able to subvert the
+      directory authority system. Fixes bug 25251; bugfix on
+      0.2.9.4-alpha. Also tracked as TROVE-2018-004.
+
+  o Minor bugfixes (memory usage):
+    - When queuing DESTROY cells on a channel, only queue the circuit-id
+      and reason fields: not the entire 514-byte cell. This fix should
+      help mitigate any bugs or attacks that fill up these queues, and
+      free more RAM for other uses. Fixes bug 24666; bugfix
+      on 0.2.5.1-alpha.
+
+  o Minor bugfixes (network layer):
+    - When closing a connection via close_connection_immediately(), we
+      mark it as "not blocked on bandwidth", to prevent later calls from
+      trying to unblock it, and give it permission to read. This fixes a
+      backtrace warning that can happen on relays under various
+      circumstances. Fixes bug 24167; bugfix on 0.1.0.1-rc.
+
+  o Minor bugfixes (OSX):
+    - Don't exit the Tor process if setrlimit() fails to change the file
+      limit (which can happen sometimes on some versions of OSX). Fixes
+      bug 21074; bugfix on 0.0.9pre5.
+
+  o Minor bugfixes (path selection):
+    - When selecting relays by bandwidth, avoid a rounding error that
+      could sometimes cause load to be imbalanced incorrectly.
+      Previously, we would always round upwards; now, we round towards
+      the nearest integer. This had the biggest effect when a relay's
+      weight adjustments should have given it weight 0, but it got
+      weight 1 instead. Fixes bug 23318; bugfix on 0.2.4.3-alpha.
+    - When calculating the fraction of nodes that have descriptors, and
+      all nodes in the network have zero bandwidths, count the number of
+      nodes instead. Fixes bug 23318; bugfix on 0.2.4.10-alpha.
+    - Actually log the total bandwidth in compute_weighted_bandwidths().
+      Fixes bug 24170; bugfix on 0.2.4.3-alpha.
+
+  o Minor bugfixes (portability, msvc):
+    - Fix a bug in the bit-counting parts of our timing-wheel code on
+      MSVC. (Note that MSVC is still not a supported build platform, due
+      to cryptographic timing channel risks.) Fixes bug 24633; bugfix
+      on 0.2.9.1-alpha.
+
+  o Minor bugfixes (relay):
+    - Make the internal channel_is_client() function look at what sort
+      of connection handshake the other side used, rather than whether
+      the other side ever sent a create_fast cell to us. Backports part
+      of the fixes from bugs 22805 and 24898.
+
+  o Minor bugfixes (spec conformance, backport from 0.3.3.3-alpha):
+    - Forbid "-0" as a protocol version. Fixes part of bug 25249; bugfix on
+      0.2.9.4-alpha.
+    - Forbid UINT32_MAX as a protocol version.  Fixes part of bug 25249;
+      bugfix on 0.2.9.4-alpha.
+
+
 Changes in version 0.3.3.2-alpha - 2018-02-10
   Tor 0.3.3.2-alpha is the second alpha in the 0.3.3.x series. It
   introduces a mechanism to handle the high loads that many relay