Hello!
The abovementioned releases are the latest in their series. They contain code that we hope will protect the network against denial-of-service attacks, and make v3 hidden services more robust in the presence of such attacks.
You can download the source, as usual, at https://dist.torproject.org/.
Note that support for 0.4.3.x will end later this month; if you're on that version, you should probably upgrade to 0.4.4.x or 0.4.5.x. See https://gitlab.torproject.org/tpo/core/team/-/wikis/NetworkTeam/CoreTorRelea... for information on our supported release series and schedules.
We anticipate that 0.4.5.x will be "officially" stable on 15 Feb, and that differences from 0.4.5.5-rc will be minimal.
Official release announcements will follow after the website updates.
Here are the changelogs:
Changes in version 0.4.4.7 - 2021-02-03 Tor 0.4.4.7 backports numerous bugfixes from later releases, including one that made v3 onion services more susceptible to denial-of-service attacks, and a feature that makes some kinds of DoS attacks harder to perform.
o Major bugfixes (onion service v3, backport from 0.4.5.3-rc): - Stop requiring a live consensus for v3 clients and services, and allow a "reasonably live" consensus instead. This allows v3 onion services to work even if the authorities fail to generate a consensus for more than 2 hours in a row. Fixes bug 40237; bugfix on 0.3.5.1-alpha.
o Major feature (exit, backport from 0.4.5.5-rc): - Re-entry into the network is now denied at the Exit level to all relays' ORPorts and authorities' ORPorts and DirPorts. This change should help mitgate a set of denial-of-service attacks. Closes ticket 2667.
o Minor feature (build system, backport from 0.4.5.4-rc): - New "make lsp" command to generate the compile_commands.json file used by the ccls language server. The "bear" program is needed for this. Closes ticket 40227.
o Minor features (compilation, backport from 0.4.5.2-rc): - Disable deprecation warnings when building with OpenSSL 3.0.0 or later. There are a number of APIs newly deprecated in OpenSSL 3.0.0 that Tor still requires. (A later version of Tor will try to stop depending on these APIs.) Closes ticket 40165.
o Minor features (crypto, backport from 0.4.5.3-rc): - Fix undefined behavior on our Keccak library. The bug only appeared on platforms with 32-byte CPU cache lines (e.g. armv5tel) and would result in wrong digests. Fixes bug 40210; bugfix on 0.2.8.1-alpha. Thanks to Bernhard Übelacker, Arnd Bergmann and weasel for diagnosing this.
o Minor bugfixes (compatibility, backport from 0.4.5.1-rc): - Strip '\r' characters when reading text files on Unix platforms. This should resolve an issue where a relay operator migrates a relay from Windows to Unix, but does not change the line ending of Tor's various state files to match the platform, and the CRLF line endings from Windows end up leaking into other files such as the extra-info document. Fixes bug 33781; bugfix on 0.0.9pre5.
o Minor bugfixes (compilation, backport from 0.4.5.3-rc): - Fix a compilation warning about unreachable fallthrough annotations when building with "--enable-all-bugs-are-fatal" on some compilers. Fixes bug 40241; bugfix on 0.3.5.4-alpha.
o Minor bugfixes (SOCKS5, backport from 0.4.5.3-rc): - Handle partial SOCKS5 messages correctly. Previously, our code would send an incorrect error message if it got a SOCKS5 request that wasn't complete. Fixes bug 40190; bugfix on 0.3.5.1-alpha.
o Minor bugfixes (testing, backport from 0.4.5.2-alpha): - Fix the `config/parse_tcp_proxy_line` test so that it works correctly on systems where the DNS provider hijacks invalid queries. Fixes part of bug 40179; bugfix on 0.4.3.1-alpha. - Fix our Python reference-implementation for the v3 onion service handshake so that it works correctly with the version of hashlib provided by Python 3.9. Fixes part of bug 40179; bugfix on 0.3.1.6-rc. - Fix the `tortls/openssl/log_one_error` test to work with OpenSSL 3.0.0. Fixes bug 40170; bugfix on 0.2.8.1-alpha.
Changes in version 0.4.3.8 - 2021-02-03 Tor 0.4.3.8 backports numerous bugfixes from later releases, including one that made v3 onion services more susceptible to denial-of-service attacks, and a feature that makes some kinds of DoS attacks harder to perform.
Note that this is, in all likelihood, the last release of Tor 0.4.3.x, which will reach end-of-life on 15 Feb 2021.
o Major bugfixes (onion service v3, backport from 0.4.5.3-rc): - Stop requiring a live consensus for v3 clients and services, and allow a "reasonably live" consensus instead. This allows v3 onion services to work even if the authorities fail to generate a consensus for more than 2 hours in a row. Fixes bug 40237; bugfix on 0.3.5.1-alpha.
o Major bugfixes (stats, onion services, backport from 0.4.4.5): - Fix a bug where we were undercounting the Tor network's total onion service traffic, by ignoring any traffic originating from clients. Now we count traffic from both clients and services. Fixes bug 40117; bugfix on 0.2.6.2-alpha.
o Major feature (exit, backport from 0.4.5.5-rc): - Re-entry into the network is now denied at the Exit level to all relays' ORPorts and authorities' ORPorts and DirPorts. This change should help mitgate a set of denial-of-service attacks. Closes ticket 2667.
o Minor feature (build system, backport from 0.4.5.4-rc): - New "make lsp" command to generate the compile_commands.json file used by the ccls language server. The "bear" program is needed for this. Closes ticket 40227.
o Minor features (compilation, backport from 0.4.5.2-rc): - Disable deprecation warnings when building with OpenSSL 3.0.0 or later. There are a number of APIs newly deprecated in OpenSSL 3.0.0 that Tor still requires. (A later version of Tor will try to stop depending on these APIs.) Closes ticket 40165.
o Minor features (crypto, backport from 0.4.5.3-rc): - Fix undefined behavior on our Keccak library. The bug only appeared on platforms with 32-byte CPU cache lines (e.g. armv5tel) and would result in wrong digests. Fixes bug 40210; bugfix on 0.2.8.1-alpha. Thanks to Bernhard Übelacker, Arnd Bergmann and weasel for diagnosing this.
o Minor bugfixes (compatibility, backport from 0.4.5.1-rc): - Strip '\r' characters when reading text files on Unix platforms. This should resolve an issue where a relay operator migrates a relay from Windows to Unix, but does not change the line ending of Tor's various state files to match the platform, and the CRLF line endings from Windows end up leaking into other files such as the extra-info document. Fixes bug 33781; bugfix on 0.0.9pre5.
o Minor bugfixes (compilation, backport from 0.4.5.1-rc): - Resolve a compilation warning that could occur in test_connection.c. Fixes bug 40113; bugfix on 0.2.9.3-alpha.
o Minor bugfixes (compilation, backport from 0.4.5.3-rc): - Fix a compilation warning about unreachable fallthrough annotations when building with "--enable-all-bugs-are-fatal" on some compilers. Fixes bug 40241; bugfix on 0.3.5.4-alpha.
o Minor bugfixes (SOCKS5, backport from 0.4.5.3-rc): - Handle partial SOCKS5 messages correctly. Previously, our code would send an incorrect error message if it got a SOCKS5 request that wasn't complete. Fixes bug 40190; bugfix on 0.3.5.1-alpha.
o Minor bugfixes (testing, backport from 0.4.5.2-alpha): - Fix the `config/parse_tcp_proxy_line` test so that it works correctly on systems where the DNS provider hijacks invalid queries. Fixes part of bug 40179; bugfix on 0.4.3.1-alpha. - Fix our Python reference-implementation for the v3 onion service handshake so that it works correctly with the version of hashlib provided by Python 3.9. Fixes part of bug 40179; bugfix on 0.3.1.6-rc. - Fix the `tortls/openssl/log_one_error` test to work with OpenSSL 3.0.0. Fixes bug 40170; bugfix on 0.2.8.1-alpha.
Changes in version 0.3.5.13 - 2020-02-03 Tor 0.3.5.13 backports numerous bugfixes from later releases, including one that made v3 onion services more susceptible to denial-of-service attacks, and a feature that makes some kinds of DoS attacks harder to perform.
o Major bugfixes (onion service v3, backport from 0.4.5.3-rc): - Stop requiring a live consensus for v3 clients and services, and allow a "reasonably live" consensus instead. This allows v3 onion services to work even if the authorities fail to generate a consensus for more than 2 hours in a row. Fixes bug 40237; bugfix on 0.3.5.1-alpha.
o Major bugfixes (stats, onion services, backport from 0.4.4.5): - Fix a bug where we were undercounting the Tor network's total onion service traffic, by ignoring any traffic originating from clients. Now we count traffic from both clients and services. Fixes bug 40117; bugfix on 0.2.6.2-alpha.
o Major feature (exit, backport from 0.4.5.5-rc): - Re-entry into the network is now denied at the Exit level to all relays' ORPorts and authorities' ORPorts and DirPorts. This change should help mitgate a set of denial-of-service attacks. Closes ticket 2667.
o Minor feature (build system, backport from 0.4.5.4-rc): - New "make lsp" command to generate the compile_commands.json file used by the ccls language server. The "bear" program is needed for this. Closes ticket 40227.
o Minor features (compilation, backport from 0.4.5.2-rc): - Disable deprecation warnings when building with OpenSSL 3.0.0 or later. There are a number of APIs newly deprecated in OpenSSL 3.0.0 that Tor still requires. (A later version of Tor will try to stop depending on these APIs.) Closes ticket 40165.
o Minor features (crypto, backport from 0.4.5.3-rc): - Fix undefined behavior on our Keccak library. The bug only appeared on platforms with 32-byte CPU cache lines (e.g. armv5tel) and would result in wrong digests. Fixes bug 40210; bugfix on 0.2.8.1-alpha. Thanks to Bernhard Übelacker, Arnd Bergmann and weasel for diagnosing this.
o Minor bugfixes (compatibility, backport from 0.4.5.1-rc): - Strip '\r' characters when reading text files on Unix platforms. This should resolve an issue where a relay operator migrates a relay from Windows to Unix, but does not change the line ending of Tor's various state files to match the platform, and the CRLF line endings from Windows end up leaking into other files such as the extra-info document. Fixes bug 33781; bugfix on 0.0.9pre5.
o Minor bugfixes (compilation, backport from 0.4.5.1-rc): - Resolve a compilation warning that could occur in test_connection.c. Fixes bug 40113; bugfix on 0.2.9.3-alpha.
o Minor bugfixes (compilation, backport from 0.4.5.3-rc): - Fix a compilation warning about unreachable fallthrough annotations when building with "--enable-all-bugs-are-fatal" on some compilers. Fixes bug 40241; bugfix on 0.3.5.4-alpha.
o Minor bugfixes (SOCKS5, backport from 0.4.5.3-rc): - Handle partial SOCKS5 messages correctly. Previously, our code would send an incorrect error message if it got a SOCKS5 request that wasn't complete. Fixes bug 40190; bugfix on 0.3.5.1-alpha.
o Minor bugfixes (testing, backport from 0.4.5.2-alpha): - Fix our Python reference-implementation for the v3 onion service handshake so that it works correctly with the version of hashlib provided by Python 3.9. Fixes part of bug 40179; bugfix on 0.3.1.6-rc. - Fix the `tortls/openssl/log_one_error` test to work with OpenSSL 3.0.0. Fixes bug 40170; bugfix on 0.2.8.1-alpha.