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Tor 0.2.6.9 is released
by Nick Mathewson 11 Jun '15

11 Jun '15

(If you want to get off this mailing list, please don't email me. Use the "unsubscribe" link at the bottom of https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-announce .) Hi! I've just put out a new stable Tor release. It is not a high-urgency item for most clients and relays, but directory authorities should upgrade, as should any clients who rely on port-based circuit isolation. Right now, the source is available on the website, and packages should become available once their maintainers build them. Changes in version 0.2.6.9 - 2015-06-11 Tor 0.2.6.9 fixes a regression in the circuit isolation code, increases the requirements for receiving an HSDir flag, and addresses some other small bugs in the systemd and sandbox code. Clients using circuit isolation should upgrade; all directory authorities should upgrade. o Major bugfixes (client-side privacy): - Properly separate out each SOCKSPort when applying stream isolation. The error occurred because each port's session group was being overwritten by a default value when the listener connection was initialized. Fixes bug 16247; bugfix on 0.2.6.3-alpha. Patch by "jojelino". o Minor feature (directory authorities, security): - The HSDir flag given by authorities now requires the Stable flag. For the current network, this results in going from 2887 to 2806 HSDirs. Also, it makes it harder for an attacker to launch a sybil attack by raising the effort for a relay to become Stable which takes at the very least 7 days to do so and by keeping the 96 hours uptime requirement for HSDir. Implements ticket 8243. o Minor bugfixes (compilation): - Build with --enable-systemd correctly when libsystemd is installed, but systemd is not. Fixes bug 16164; bugfix on 0.2.6.3-alpha. Patch from Peter Palfrader. o Minor bugfixes (Linux seccomp2 sandbox): - Fix sandboxing to work when running as a relaymby renaming of secret_id_key, and allowing the eventfd2 and futex syscalls. Fixes bug 16244; bugfix on 0.2.6.1-alpha. Patch by Peter Palfrader. - Allow systemd connections to work with the Linux seccomp2 sandbox code. Fixes bug 16212; bugfix on 0.2.6.2-alpha. Patch by Peter Palfrader. o Minor bugfixes (tests): - Fix a crash in the unit tests when built with MSVC2013. Fixes bug 16030; bugfix on 0.2.6.2-alpha. Patch from "NewEraCracker".

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Tor 0.2.6.8 is released.
by Nick Mathewson 21 May '15

21 May '15

Hi, I've just put out a new stable Tor release. It is not a high-urgency item for most clients and relays, but directory authorities should upgrade. Right now, the source is available on the website, and packages should become available one their maintainers build them. Tor 0.2.6.8 fixes a bit of dodgy code in parsing INTRODUCE2 cells, and fixes an authority-side bug in assigning the HSDir flag. All directory authorities should upgrade. Here are the changes in this version: Changes in version 0.2.6.8 - 2015-05-21 Tor 0.2.6.8 fixes a bit of dodgy code in parsing INTRODUCE2 cells, and fixes an authority-side bug in assigning the HSDir flag. All directory authorities should upgrade. o Major bugfixes (hidden services, backport from 0.2.7.1-alpha): - Revert commit that made directory authorities assign the HSDir flag to relay without a DirPort; this was bad because such relays can't handle BEGIN_DIR cells. Fixes bug 15850; bugfix on tor-0.2.6.3-alpha. o Minor bugfixes (hidden service, backport from 0.2.7.1-alpha): - Fix an out-of-bounds read when parsing invalid INTRODUCE2 cells on a client authorized hidden service. Fixes bug 15823; bugfix on 0.2.1.6-alpha. o Minor features (geoip): - Update geoip to the April 8 2015 Maxmind GeoLite2 Country database. - Update geoip6 to the April 8 2015 Maxmind GeoLite2 Country database.

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Tor 0.2.5.12 and 0.2.6.7 are released
by Roger Dingledine 07 Apr '15

07 Apr '15

Tor 0.2.5.12 and 0.2.6.7 fix two security issues that could be used by an attacker to crash hidden services, or crash clients visiting hidden services. Hidden services should upgrade as soon as possible; clients should upgrade whenever packages become available. These releases also contain two simple improvements to make hidden services a bit less vulnerable to denial-of-service attacks. We also made a Tor 0.2.4.27 release so that Debian stable can easily integrate these fixes. The Tor Browser team is currently evaluating whether to put out a new Tor Browser stable release with these fixes, or wait until next week for their scheduled next stable release. Changes in version 0.2.5.12 - 2015-04-06 o Major bugfixes (security, hidden service): - Fix an issue that would allow a malicious client to trigger an assertion failure and halt a hidden service. Fixes bug 15600; bugfix on 0.2.1.6-alpha. Reported by "disgleirio". - Fix a bug that could cause a client to crash with an assertion failure when parsing a malformed hidden service descriptor. Fixes bug 15601; bugfix on 0.2.1.5-alpha. Found by "DonnchaC". o Minor features (DoS-resistance, hidden service): - Introduction points no longer allow multiple INTRODUCE1 cells to arrive on the same circuit. This should make it more expensive for attackers to overwhelm hidden services with introductions. Resolves ticket 15515. Changes in version 0.2.6.7 - 2015-04-06 o Major bugfixes (security, hidden service): - Fix an issue that would allow a malicious client to trigger an assertion failure and halt a hidden service. Fixes bug 15600; bugfix on 0.2.1.6-alpha. Reported by "disgleirio". - Fix a bug that could cause a client to crash with an assertion failure when parsing a malformed hidden service descriptor. Fixes bug 15601; bugfix on 0.2.1.5-alpha. Found by "DonnchaC". o Minor features (DoS-resistance, hidden service): - Introduction points no longer allow multiple INTRODUCE1 cells to arrive on the same circuit. This should make it more expensive for attackers to overwhelm hidden services with introductions. Resolves ticket 15515. - Decrease the amount of reattempts that a hidden service performs when its rendezvous circuits fail. This reduces the computational cost for running a hidden service under heavy load. Resolves ticket 11447.

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Tor 0.2.5.11 is released.
by Nick Mathewson 24 Mar '15

24 Mar '15

Hello! I released Tor 0.2.5.11 last week. This is the formal announcement. (Per usual practice with non-critical stable releases, I've delayed the tor-announce announcement to give distributions have a chance to make packages. If you are a packager and you didn't notice that, please let me know and I'll put you on the list of people I notify extra-early about new releases.) This is the second stable 0.2.5 release. (The first came out in October.) Going forward, the 0.2.5 series will only receive patches for serious issues. You may want to consider upgrading to 0.2.6 soon; it's going to be officially stable pretty soon now. You can get the source code for Tor 0.2.5.11 at https://dist.torproject.org/ and directly from the download page at the Tor website. This version of Tor also appears in TorBrowser 4.0.5. Changes in version 0.2.5.11 - 2015-03-17 Tor 0.2.5.11 is the second stable release in the 0.2.5 series. It backports several bugfixes from the 0.2.6 branch, including a couple of medium-level security fixes for relays and exit nodes. It also updates the list of directory authorities. o Directory authority changes: - Remove turtles as a directory authority. - Add longclaw as a new (v3) directory authority. This implements ticket 13296. This keeps the directory authority count at 9. - The directory authority Faravahar has a new IP address. This closes ticket 14487. o Major bugfixes (crash, OSX, security): - Fix a remote denial-of-service opportunity caused by a bug in OSX's _strlcat_chk() function. Fixes bug 15205; bug first appeared in OSX 10.9. o Major bugfixes (relay, stability, possible security): - Fix a bug that could lead to a relay crashing with an assertion failure if a buffer of exactly the wrong layout was passed to buf_pullup() at exactly the wrong time. Fixes bug 15083; bugfix on 0.2.0.10-alpha. Patch from 'cypherpunks'. - Do not assert if the 'data' pointer on a buffer is advanced to the very end of the buffer; log a BUG message instead. Only assert if it is past that point. Fixes bug 15083; bugfix on 0.2.0.10-alpha. o Major bugfixes (exit node stability): - Fix an assertion failure that could occur under high DNS load. Fixes bug 14129; bugfix on Tor 0.0.7rc1. Found by "jowr"; diagnosed and fixed by "cypherpunks". o Major bugfixes (Linux seccomp2 sandbox): - Upon receiving sighup with the seccomp2 sandbox enabled, do not crash during attempts to call wait4. Fixes bug 15088; bugfix on 0.2.5.1-alpha. Patch from "sanic". o Minor features (controller): - New "GETINFO bw-event-cache" to get information about recent bandwidth events. Closes ticket 14128. Useful for controllers to get recent bandwidth history after the fix for ticket 13988. o Minor features (geoip): - Update geoip to the March 3 2015 Maxmind GeoLite2 Country database. - Update geoip6 to the March 3 2015 Maxmind GeoLite2 Country database. o Minor bugfixes (client, automapping): - Avoid crashing on torrc lines for VirtualAddrNetworkIPv[4|6] when no value follows the option. Fixes bug 14142; bugfix on 0.2.4.7-alpha. Patch by "teor". - Fix a memory leak when using AutomapHostsOnResolve. Fixes bug 14195; bugfix on 0.1.0.1-rc. o Minor bugfixes (compilation): - Build without warnings with the stock OpenSSL srtp.h header, which has a duplicate declaration of SSL_get_selected_srtp_profile(). Fixes bug 14220; this is OpenSSL's bug, not ours. o Minor bugfixes (directory authority): - Allow directory authorities to fetch more data from one another if they find themselves missing lots of votes. Previously, they had been bumping against the 10 MB queued data limit. Fixes bug 14261; bugfix on 0.1.2.5-alpha. - Enlarge the buffer to read bwauth generated files to avoid an issue when parsing the file in dirserv_read_measured_bandwidths(). Fixes bug 14125; bugfix on 0.2.2.1-alpha. o Minor bugfixes (statistics): - Increase period over which bandwidth observations are aggregated from 15 minutes to 4 hours. Fixes bug 13988; bugfix on 0.0.8pre1. o Minor bugfixes (preventative security, C safety): - When reading a hexadecimal, base-32, or base-64 encoded value from a string, always overwrite the whole output buffer. This prevents some bugs where we would look at (but fortunately, not reveal) uninitialized memory on the stack. Fixes bug 14013; bugfix on all versions of Tor.

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Tor 0.2.4.26 is released
by Nick Mathewson 24 Mar '15

24 Mar '15

Hello! I released Tor 0.2.4.26 last week. This is the formal announcement. (Per usual practice with non-critical stable releases, I've delayed the tor-announce announcement to give distributions have a chance to make packages. If you are a packager and you didn't notice that, please let me know and I'll put you on the list of people I notify extra-early about new releases.) Tor 0.2.4 is the oldest supported release series. It will receive only patches for really serious issues. Most people should consider upgrading to 0.2.5 or 0.2.6 instead. You can get the source code for Tor 0.2.4.26 at https://dist.torproject.org/ Changes in version 0.2.4.26 - 2015-03-17 Tor 0.2.4.26 includes an updated list of directory authorities. It also backports a couple of stability and security bugfixes from 0.2.5 and beyond. o Directory authority changes: - Remove turtles as a directory authority. - Add longclaw as a new (v3) directory authority. This implements ticket 13296. This keeps the directory authority count at 9. - The directory authority Faravahar has a new IP address. This closes ticket 14487. o Major bugfixes (exit node stability, also in 0.2.6.3-alpha): - Fix an assertion failure that could occur under high DNS load. Fixes bug 14129; bugfix on Tor 0.0.7rc1. Found by "jowr"; diagnosed and fixed by "cypherpunks". o Major bugfixes (relay, stability, possible security, also in 0.2.6.4-rc): - Fix a bug that could lead to a relay crashing with an assertion failure if a buffer of exactly the wrong layout was passed to buf_pullup() at exactly the wrong time. Fixes bug 15083; bugfix on 0.2.0.10-alpha. Patch from 'cypherpunks'. - Do not assert if the 'data' pointer on a buffer is advanced to the very end of the buffer; log a BUG message instead. Only assert if it is past that point. Fixes bug 15083; bugfix on 0.2.0.10-alpha. o Minor features (geoip): - Update geoip to the March 3 2015 Maxmind GeoLite2 Country database. - Update geoip6 to the March 3 2015 Maxmind GeoLite2 Country database.

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Tor 0.2.5.10 is released!
by Nick Mathewson 25 Oct '14

25 Oct '14

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello, all. This is a release announcement for Tor 0.2.5.10, which I released as source yesterday. You can download the source from the usual places on our website. Some operating system packages should already be available; others will likely be released over the next week. (Usually, I'd wait for more packages to be available before announcing a stable release, but people have been asking me questions about whether this is official or not. So there you have it!) Changes in version 0.2.5.10 - 2014-10-24 Tor 0.2.5.10 is the first stable release in the 0.2.5 series. It adds several new security features, including improved denial-of-service resistance for relays, new compiler hardening options, and a system-call sandbox for hardened installations on Linux (requires seccomp2). The controller protocol has several new features, resolving IPv6 addresses should work better than before, and relays should be a little more CPU-efficient. We've added support for more OpenBSD and FreeBSD transparent proxy types. We've improved the build system and testing infrastructure to allow unit testing of more parts of the Tor codebase. Finally, we've addressed several nagging pluggable transport usability issues, and included numerous other small bugfixes and features mentioned below. This release marks end-of-life for Tor 0.2.3.x; those Tor versions have accumulated many known flaws; everyone should upgrade. o Major features (security): - The ntor handshake is now on-by-default, no matter what the directory authorities recommend. Implements ticket 8561. - Make the "tor-gencert" tool used by directory authority operators create 2048-bit signing keys by default (rather than 1024-bit, since 1024-bit is uncomfortably small these days). Addresses ticket 10324. - Warn about attempts to run hidden services and relays in the same process: that's probably not a good idea. Closes ticket 12908. - Disable support for SSLv3. All versions of OpenSSL in use with Tor today support TLS 1.0 or later, so we can safely turn off support for this old (and insecure) protocol. Fixes bug 13426. o Major features (relay security, DoS-resistance): - When deciding whether we have run out of memory and we need to close circuits, also consider memory allocated in buffers for streams attached to each circuit. This change, which extends an anti-DoS feature introduced in 0.2.4.13-alpha and improved in 0.2.4.14-alpha, lets Tor exit relays better resist more memory-based DoS attacks than before. Since the MaxMemInCellQueues option now applies to all queues, it is renamed to MaxMemInQueues. This feature fixes bug 10169. - Avoid hash-flooding denial-of-service attacks by using the secure SipHash-2-4 hash function for our hashtables. Without this feature, an attacker could degrade performance of a targeted client or server by flooding their data structures with a large number of entries to be stored at the same hash table position, thereby slowing down the Tor instance. With this feature, hash table positions are derived from a randomized cryptographic key, and an attacker cannot predict which entries will collide. Closes ticket 4900. - If you don't specify MaxMemInQueues yourself, Tor now tries to pick a good value based on your total system memory. Previously, the default was always 8 GB. You can still override the default by setting MaxMemInQueues yourself. Resolves ticket 11396. o Major features (bridges and pluggable transports): - Add support for passing arguments to managed pluggable transport proxies. Implements ticket 3594. - Bridges now track GeoIP information and the number of their users even when pluggable transports are in use, and report usage statistics in their extra-info descriptors. Resolves tickets 4773 and 5040. - Don't launch pluggable transport proxies if we don't have any bridges configured that would use them. Now we can list many pluggable transports, and Tor will dynamically start one when it hears a bridge address that needs it. Resolves ticket 5018. - The bridge directory authority now assigns status flags (Stable, Guard, etc) to bridges based on thresholds calculated over all Running bridges. Now bridgedb can finally make use of its features to e.g. include at least one Stable bridge in its answers. Fixes bug 9859. o Major features (controller): - Extend ORCONN controller event to include an "ID" parameter, and add four new controller event types CONN_BW, CIRC_BW, CELL_STATS, and TB_EMPTY that show connection and circuit usage. The new events are emitted in private Tor networks only, with the goal of being able to better track performance and load during full-network simulations. Implements proposal 218 and ticket 7359. o Major features (relay performance): - Speed up server-side lookups of rendezvous and introduction point circuits by using hashtables instead of linear searches. These functions previously accounted between 3 and 7% of CPU usage on some busy relays. Resolves ticket 9841. - Avoid wasting CPU when extending a circuit over a channel that is nearly out of circuit IDs. Previously, we would do a linear scan over possible circuit IDs before finding one or deciding that we had exhausted our possibilities. Now, we try at most 64 random circuit IDs before deciding that we probably won't succeed. Fixes a possible root cause of ticket 11553. o Major features (seccomp2 sandbox, Linux only): - Use the seccomp2 syscall filtering facility on Linux to limit which system calls Tor can invoke. This is an experimental, Linux-only feature to provide defense-in-depth against unknown attacks. To try turning it on, set "Sandbox 1" in your torrc file. Please be ready to report bugs. We hope to add support for better sandboxing in the future, including more fine-grained filters, better division of responsibility, and support for more platforms. This work has been done by Cristian-Matei Toader for Google Summer of Code. Resolves tickets 11351 and 11465. o Major features (testing networks): - Make testing Tor networks bootstrap better: lower directory fetch retry schedules and maximum interval without directory requests, and raise maximum download tries. Implements ticket 6752. - Add make target 'test-network' to run tests on a Chutney network. Implements ticket 8530. o Major features (other): - On some platforms (currently: recent OSX versions, glibc-based platforms that support the ELF format, and a few other Unix-like operating systems), Tor can now dump stack traces when a crash occurs or an assertion fails. By default, traces are dumped to stderr (if possible) and to any logs that are reporting errors. Implements ticket 9299. o Deprecated versions: - Tor 0.2.3.x has reached end-of-life; it has received no patches or attention for some while. o Major bugfixes (security, directory authorities): - Directory authorities now include a digest of each relay's identity key as a part of its microdescriptor. This is a workaround for bug 11743 (reported by "cypherpunks"), where Tor clients do not support receiving multiple microdescriptors with the same SHA256 digest in the same consensus. When clients receive a consensus like this, they only use one of the relays. Without this fix, a hostile relay could selectively disable some client use of target relays by constructing a router descriptor with a different identity and the same microdescriptor parameters and getting the authorities to list it in a microdescriptor consensus. This fix prevents an attacker from causing a microdescriptor collision, because the router's identity is not forgeable. o Major bugfixes (openssl bug workaround): - Avoid crashing when using OpenSSL version 0.9.8zc, 1.0.0o, or 1.0.1j, built with the 'no-ssl3' configuration option. Fixes bug 13471. This is a workaround for an OpenSSL bug. o Major bugfixes (client): - Perform circuit cleanup operations even when circuit construction operations are disabled (because the network is disabled, or because there isn't enough directory information). Previously, when we were not building predictive circuits, we were not closing expired circuits either. Fixes bug 8387; bugfix on 0.1.1.11-alpha. This bug became visible in 0.2.4.10-alpha when we became more strict about when we have "enough directory information to build circuits". o Major bugfixes (client, pluggable transports): - When managing pluggable transports, use OS notification facilities to learn if they have crashed, and don't attempt to kill any process that has already exited. Fixes bug 8746; bugfix on 0.2.3.6-alpha. o Major bugfixes (relay denial of service): - Instead of writing destroy cells directly to outgoing connection buffers, queue them and intersperse them with other outgoing cells. This can prevent a set of resource starvation conditions where too many pending destroy cells prevent data cells from actually getting delivered. Reported by "oftc_must_be_destroyed". Fixes bug 7912; bugfix on 0.2.0.1-alpha. o Major bugfixes (relay): - Avoid queuing or sending destroy cells for circuit ID zero when we fail to send a CREATE cell. Fixes bug 12848; bugfix on 0.0.8pre1. Found and fixed by "cypherpunks". - Fix ORPort reachability detection on relays running behind a proxy, by correctly updating the "local" mark on the controlling channel when changing the address of an or_connection_t after the handshake. Fixes bug 12160; bugfix on 0.2.4.4-alpha. - Use a direct dirport connection when uploading non-anonymous descriptors to the directory authorities. Previously, relays would incorrectly use tunnel connections under a fairly wide variety of circumstances. Fixes bug 11469; bugfix on 0.2.4.3-alpha. - When a circuit accidentally has the same circuit ID for its forward and reverse direction, correctly detect the direction of cells using that circuit. Previously, this bug made roughly one circuit in a million non-functional. Fixes bug 12195; this is a bugfix on every version of Tor. o Minor features (security): - New --enable-expensive-hardening option to enable security hardening options that consume nontrivial amounts of CPU and memory. Right now, this includes AddressSanitizer and UbSan, which are supported in newer versions of GCC and Clang. Closes ticket 11477. - Authorities now assign the Guard flag to the fastest 25% of the network (it used to be the fastest 50%). Also raise the consensus weight that guarantees the Guard flag from 250 to 2000. For the current network, this results in about 1100 guards, down from 2500. This step paves the way for moving the number of entry guards down to 1 (proposal 236) while still providing reasonable expected performance for most users. Implements ticket 12690. o Minor features (security, memory management): - Memory allocation tricks (mempools and buffer freelists) are now disabled by default. You can turn them back on with --enable-mempools and --enable-buf-freelists respectively. We're disabling these features because malloc performance is good enough on most platforms, and a similar feature in OpenSSL exacerbated exploitation of the Heartbleed attack. Resolves ticket 11476. o Minor features (bridge client): - Report a more useful failure message when we can't connect to a bridge because we don't have the right pluggable transport configured. Resolves ticket 9665. Patch from Fábio J. Bertinatto. o Minor features (bridge): - Add an ExtORPortCookieAuthFileGroupReadable option to make the cookie file for the ExtORPort g+r by default. o Minor features (bridges, pluggable transports): - Bridges now write the SHA1 digest of their identity key fingerprint (that is, a hash of a hash of their public key) to notice-level logs, and to a new hashed-fingerprint file. This information will help bridge operators look up their bridge in Globe and similar tools. Resolves ticket 10884. - Improve the message that Tor displays when running as a bridge using pluggable transports without an Extended ORPort listener. Also, log the message in the log file too. Resolves ticket 11043. - Add threshold cutoffs to the networkstatus document created by the Bridge Authority. Fixes bug 1117. - On Windows, spawn background processes using the CREATE_NO_WINDOW flag. Now Tor Browser Bundle 3.5 with pluggable transports enabled doesn't pop up a blank console window. (In Tor Browser Bundle 2.x, Vidalia set this option for us.) Implements ticket 10297. o Minor features (build): - The configure script has a --disable-seccomp option to turn off support for libseccomp on systems that have it, in case it (or Tor's use of it) is broken. Resolves ticket 11628. - Assume that a user using ./configure --host wants to cross-compile, and give an error if we cannot find a properly named tool-chain. Add a --disable-tool-name-check option to proceed nevertheless. Addresses ticket 9869. Patch by Benedikt Gollatz. - If we run ./configure and the compiler recognizes -fstack-protector but the linker rejects it, warn the user about a potentially missing libssp package. Addresses ticket 9948. Patch from Benedikt Gollatz. - Add support for `--library-versions` flag. Implements ticket 6384. - Return the "unexpected sendme" warnings to a warn severity, but make them rate limited, to help diagnose ticket 8093. - Detect a missing asciidoc, and warn the user about it, during configure rather than at build time. Fixes issue 6506. Patch from Arlo Breault. o Minor features (client): - Add a new option, PredictedPortsRelevanceTime, to control how long after having received a request to connect to a given port Tor will try to keep circuits ready in anticipation of future requests for that port. Patch from "unixninja92"; implements ticket 9176. o Minor features (config options and command line): - Add an --allow-missing-torrc commandline option that tells Tor to run even if the configuration file specified by -f is not available. Implements ticket 10060. - Add support for the TPROXY transparent proxying facility on Linux. See documentation for the new TransProxyType option for more details. Implementation by "thomo". Closes ticket 10582. o Minor features (config options): - Config (torrc) lines now handle fingerprints which are missing their initial '$'. Resolves ticket 4341; improvement over 0.0.9pre5. - Support a --dump-config option to print some or all of the configured options. Mainly useful for debugging the command-line option parsing code. Helps resolve ticket 4647. - Raise awareness of safer logging: notify user of potentially unsafe config options, like logging more verbosely than severity "notice" or setting SafeLogging to 0. Resolves ticket 5584. - Add a new configuration option TestingV3AuthVotingStartOffset that bootstraps a network faster by changing the timing for consensus votes. Addresses ticket 8532. - Add a new torrc option "ServerTransportOptions" that allows bridge operators to pass configuration parameters to their pluggable transports. Resolves ticket 8929. - The config (torrc) file now accepts bandwidth and space limits in bits as well as bytes. (Anywhere that you can say "2 Kilobytes", you can now say "16 kilobits", and so on.) Resolves ticket 9214. Patch by CharlieB. o Minor features (controller): - Make the entire exit policy available from the control port via GETINFO exit-policy/*. Implements enhancement 7952. Patch from "rl1987". - Because of the fix for ticket 11396, the real limit for memory usage may no longer match the configured MaxMemInQueues value. The real limit is now exposed via GETINFO limits/max-mem-in-queues. - Add a new "HS_DESC" controller event that reports activities related to hidden service descriptors. Resolves ticket 8510. - New "DROPGUARDS" controller command to forget all current entry guards. Not recommended for ordinary use, since replacing guards too frequently makes several attacks easier. Resolves ticket 9934; patch from "ra". - Implement the TRANSPORT_LAUNCHED control port event that notifies controllers about new launched pluggable transports. Resolves ticket 5609. o Minor features (diagnostic): - When logging a warning because of bug 7164, additionally check the hash table for consistency (as proposed on ticket 11737). This may help diagnose bug 7164. - When we log a heartbeat, log how many one-hop circuits we have that are at least 30 minutes old, and log status information about a few of them. This is an attempt to track down bug 8387. - When encountering an unexpected CR while writing text to a file on Windows, log the name of the file. Should help diagnosing bug 11233. - Give more specific warnings when a client notices that an onion handshake has failed. Fixes ticket 9635. - Add significant new logging code to attempt to diagnose bug 12184, where relays seem to run out of available circuit IDs. - Improve the diagnostic log message for bug 8387 even further to try to improve our odds of figuring out why one-hop directory circuits sometimes do not get closed. - Add more log messages to diagnose bug 7164, which causes intermittent "microdesc_free() called but md was still referenced" warnings. We now include more information, to figure out why we might be cleaning a microdescriptor for being too old if it's still referenced by a live node_t object. - Log current accounting state (bytes sent and received + remaining time for the current accounting period) in the relay's heartbeat message. Implements ticket 5526; patch from Peter Retzlaff. o Minor features (geoip): - Update geoip and geoip6 to the August 7 2014 Maxmind GeoLite2 Country database. o Minor features (interface): - Generate a warning if any ports are listed in the SocksPolicy, DirPolicy, AuthDirReject, AuthDirInvalid, AuthDirBadDir, or AuthDirBadExit options. (These options only support address ranges.) Fixes part of ticket 11108. o Minor features (kernel API usage): - Use the SOCK_NONBLOCK socket type, if supported, to open nonblocking sockets in a single system call. Implements ticket 5129. o Minor features (log messages): - When ServerTransportPlugin is set on a bridge, Tor can write more useful statistics about bridge use in its extrainfo descriptors, but only if the Extended ORPort ("ExtORPort") is set too. Add a log message to inform the user in this case. Resolves ticket 9651. - When receiving a new controller connection, log the origin address. Resolves ticket 9698; patch from "sigpipe". - When logging OpenSSL engine status at startup, log the status of more engines. Fixes ticket 10043; patch from Joshua Datko. o Minor features (log verbosity): - Demote the message that we give when a flushing connection times out for too long from NOTICE to INFO. It was usually meaningless. Resolves ticket 5286. - Don't log so many notice-level bootstrapping messages at startup about downloading descriptors. Previously, we'd log a notice whenever we learned about more routers. Now, we only log a notice at every 5% of progress. Fixes bug 9963. - Warn less verbosely when receiving a malformed ESTABLISH_RENDEZVOUS cell. Fixes ticket 11279. o Minor features (performance): - If we're using the pure-C 32-bit curve25519_donna implementation of curve25519, build it with the -fomit-frame-pointer option to make it go faster on register-starved hosts. This improves our handshake performance by about 6% on i386 hosts without nacl. Closes ticket 8109. o Minor features (relay): - If a circuit timed out for at least 3 minutes, check if we have a new external IP address, and publish a new descriptor with the new IP address if it changed. Resolves ticket 2454. o Minor features (testing): - If Python is installed, "make check" now runs extra tests beyond the unit test scripts. - When bootstrapping a test network, sometimes very few relays get the Guard flag. Now a new option "TestingDirAuthVoteGuard" can specify a set of relays which should be voted Guard regardless of their uptime or bandwidth. Addresses ticket 9206. o Minor features (transparent proxy, *BSD): - Support FreeBSD's ipfw firewall interface for TransPort ports on FreeBSD. To enable it, set "TransProxyType ipfw". Resolves ticket 10267; patch from "yurivict". - Support OpenBSD's divert-to rules with the pf firewall for transparent proxy ports. To enable it, set "TransProxyType pf-divert". This allows Tor to run a TransPort transparent proxy port on OpenBSD 4.4 or later without root privileges. See the pf.conf(5) manual page for information on configuring pf to use divert-to rules. Closes ticket 10896; patch from Dana Koch. o Minor bugfixes (bridge client): - Stop accepting bridge lines containing hostnames. Doing so would cause clients to perform DNS requests on the hostnames, which was not sensible behavior. Fixes bug 10801; bugfix on 0.2.0.1-alpha. o Minor bugfixes (bridges): - Avoid potential crashes or bad behavior when launching a server-side managed proxy with ORPort or ExtORPort temporarily disabled. Fixes bug 9650; bugfix on 0.2.3.16-alpha. - Fix a bug where the first connection works to a bridge that uses a pluggable transport with client-side parameters, but we don't send the client-side parameters on subsequent connections. (We don't use any pluggable transports with client-side parameters yet, but ScrambleSuit will soon become the first one.) Fixes bug 9162; bugfix on 0.2.0.3-alpha. Based on a patch from "rl1987". o Minor bugfixes (build, auxiliary programs): - Stop preprocessing the "torify" script with autoconf, since it no longer refers to LOCALSTATEDIR. Fixes bug 5505; patch from Guilhem. - The tor-fw-helper program now follows the standard convention and exits with status code "0" on success. Fixes bug 9030; bugfix on 0.2.3.1-alpha. Patch by Arlo Breault. - Corrected ./configure advice for what openssl dev package you should install on Debian. Fixes bug 9207; bugfix on 0.2.0.1-alpha. o Minor bugfixes (client): - Avoid "Tried to open a socket with DisableNetwork set" warnings when starting a client with bridges configured and DisableNetwork set. (Tor launcher starts Tor with DisableNetwork set the first time it runs.) Fixes bug 10405; bugfix on 0.2.3.9-alpha. - Improve the log message when we can't connect to a hidden service because all of the hidden service directory nodes hosting its descriptor are excluded. Improves on our fix for bug 10722, which was a bugfix on 0.2.0.10-alpha. - Raise a control port warning when we fail to connect to all of our bridges. Previously, we didn't inform the controller, and the bootstrap process would stall. Fixes bug 11069; bugfix on 0.2.1.2-alpha. - Exit immediately when a process-owning controller exits. Previously, tor relays would wait for a little while after their controller exited, as if they had gotten an INT signal -- but this was problematic, since there was no feedback for the user. To do a clean shutdown, controllers should send an INT signal and give Tor a chance to clean up. Fixes bug 10449; bugfix on 0.2.2.28-beta. - Stop attempting to connect to bridges before our pluggable transports are configured (harmless but resulted in some erroneous log messages). Fixes bug 11156; bugfix on 0.2.3.2-alpha. - Fix connections to IPv6 addresses over SOCKS5. Previously, we were generating incorrect SOCKS5 responses, and confusing client applications. Fixes bug 10987; bugfix on 0.2.4.7-alpha. o Minor bugfixes (client, DNSPort): - When using DNSPort, try to respond to AAAA requests with AAAA answers. Previously, we hadn't looked at the request type when deciding which answer type to prefer. Fixes bug 10468; bugfix on 0.2.4.7-alpha. - When receiving a DNS query for an unsupported record type, reply with no answer rather than with a NOTIMPL error. This behavior isn't correct either, but it will break fewer client programs, we hope. Fixes bug 10268; bugfix on 0.2.0.1-alpha. Original patch from "epoch". o Minor bugfixes (client, logging during bootstrap): - Only report the first fatal bootstrap error on a given OR connection. This stops us from telling the controller bogus error messages like "DONE". Fixes bug 10431; bugfix on 0.2.1.1-alpha. - Avoid generating spurious warnings when starting with DisableNetwork enabled. Fixes bug 11200 and bug 10405; bugfix on 0.2.3.9-alpha. o Minor bugfixes (closing OR connections): - If write_to_buf() in connection_write_to_buf_impl_() ever fails, check if it's an or_connection_t and correctly call connection_or_close_for_error() rather than connection_mark_for_close() directly. Fixes bug 11304; bugfix on 0.2.4.4-alpha. - When closing all connections on setting DisableNetwork to 1, use connection_or_close_normally() rather than closing OR connections out from under the channel layer. Fixes bug 11306; bugfix on 0.2.4.4-alpha. o Minor bugfixes (code correctness): - Previously we used two temporary files when writing descriptors to disk; now we only use one. Fixes bug 1376. - Remove an erroneous (but impossible and thus harmless) pointer comparison that would have allowed compilers to skip a bounds check in channeltls.c. Fixes bugs 10313 and 9980; bugfix on 0.2.0.10-alpha. Noticed by Jared L Wong and David Fifield. - Fix an always-true assertion in pluggable transports code so it actually checks what it was trying to check. Fixes bug 10046; bugfix on 0.2.3.9-alpha. Found by "dcb". o Minor bugfixes (command line): - Use a single command-line parser for parsing torrc options on the command line and for finding special command-line options to avoid inconsistent behavior for torrc option arguments that have the same names as command-line options. Fixes bugs 4647 and 9578; bugfix on 0.0.9pre5. - No longer allow 'tor --hash-password' with no arguments. Fixes bug 9573; bugfix on 0.0.9pre5. o Minor bugfixes (compilation): - Compile correctly with builds and forks of OpenSSL (such as LibreSSL) that disable compression. Fixes bug 12602; bugfix on 0.2.1.1-alpha. Patch from "dhill". - Restore the ability to compile Tor with V2_HANDSHAKE_SERVER turned off (that is, without support for v2 link handshakes). Fixes bug 4677; bugfix on 0.2.3.2-alpha. Patch from "piet". - In routerlist_assert_ok(), don't take the address of a routerinfo's cache_info member unless that routerinfo is non-NULL. Fixes bug 13096; bugfix on 0.1.1.9-alpha. Patch by "teor". - Fix a large number of false positive warnings from the clang analyzer static analysis tool. This should make real warnings easier for clang analyzer to find. Patch from "teor". Closes ticket 13036. - Resolve GCC complaints on OpenBSD about discarding constness in TO_{ORIGIN,OR}_CIRCUIT functions. Fixes part of bug 11633; bugfix on 0.1.1.23. Patch from Dana Koch. - Resolve clang complaints on OpenBSD with -Wshorten-64-to-32 due to treatment of long and time_t as comparable types. Fixes part of bug 11633. Patch from Dana Koch. - When deciding whether to build the 64-bit curve25519 implementation, detect platforms where we can compile 128-bit arithmetic but cannot link it. Fixes bug 11729; bugfix on 0.2.4.8-alpha. Patch from "conradev". - Fix compilation when DNS_CACHE_DEBUG is enabled. Fixes bug 11761; bugfix on 0.2.3.13-alpha. Found by "cypherpunks". - Fix compilation with dmalloc. Fixes bug 11605; bugfix on 0.2.4.10-alpha. - Build and run correctly on systems like OpenBSD-current that have patched OpenSSL to remove get_cipher_by_char and/or its implementations. Fixes issue 13325. o Minor bugfixes (controller and command-line): - If changing a config option via "setconf" fails in a recoverable way, we used to nonetheless write our new control ports to the file described by the "ControlPortWriteToFile" option. Now we only write out that file if we successfully switch to the new config option. Fixes bug 5605; bugfix on 0.2.2.26-beta. Patch from "Ryman". o Minor bugfixes (directory server): - No longer accept malformed http headers when parsing urls from headers. Now we reply with Bad Request ("400"). Fixes bug 2767; bugfix on 0.0.6pre1. - When sending a compressed set of descriptors or microdescriptors, make sure to finalize the zlib stream. Previously, we would write all the compressed data, but if the last descriptor we wanted to send was missing or too old, we would not mark the stream as finished. This caused problems for decompression tools. Fixes bug 11648; bugfix on 0.1.1.23. o Minor bugfixes (hidden service): - Only retry attempts to connect to a chosen rendezvous point 8 times, not 30. Fixes bug 4241; bugfix on 0.1.0.1-rc. o Minor bugfixes (interface): - Reject relative control socket paths and emit a warning. Previously, single-component control socket paths would be rejected, but Tor would not log why it could not validate the config. Fixes bug 9258; bugfix on 0.2.3.16-alpha. o Minor bugfixes (log messages): - Fix a bug where clients using bridges would report themselves as 50% bootstrapped even without a live consensus document. Fixes bug 9922; bugfix on 0.2.1.1-alpha. - Suppress a warning where, if there's only one directory authority in the network, we would complain that votes and signatures cannot be uploaded to other directory authorities. Fixes bug 10842; bugfix on 0.2.2.26-beta. - Report bootstrapping progress correctly when we're downloading microdescriptors. We had updated our "do we have enough microdescs to begin building circuits?" logic most recently in 0.2.4.10-alpha (see bug 5956), but we left the bootstrap status event logic at "how far through getting 1/4 of them are we?" Fixes bug 9958; bugfix on 0.2.2.36, which is where they diverged (see bug 5343). o Minor bugfixes (logging): - Downgrade "Unexpected onionskin length after decryption" warning to a protocol-warn, since there's nothing relay operators can do about a client that sends them a malformed create cell. Resolves bug 12996; bugfix on 0.0.6rc1. - Log more specific warnings when we get an ESTABLISH_RENDEZVOUS cell on a cannibalized or non-OR circuit. Resolves ticket 12997. - When logging information about an EXTEND2 or EXTENDED2 cell, log their names correctly. Fixes part of bug 12700; bugfix on 0.2.4.8-alpha. - When logging information about a relay cell whose command we don't recognize, log its command as an integer. Fixes part of bug 12700; bugfix on 0.2.1.10-alpha. - Escape all strings from the directory connection before logging them. Fixes bug 13071; bugfix on 0.1.1.15. Patch from "teor". - Squelch a spurious LD_BUG message "No origin circuit for successful SOCKS stream" in certain hidden service failure cases; fixes bug 10616. - Downgrade the severity of the 'unexpected sendme cell from client' from 'warn' to 'protocol warning'. Closes ticket 8093. o Minor bugfixes (misc code correctness): - In munge_extrainfo_into_routerinfo(), check the return value of memchr(). This would have been a serious issue if we ever passed it a non-extrainfo. Fixes bug 8791; bugfix on 0.2.0.6-alpha. Patch from Arlo Breault. - On the chance that somebody manages to build Tor on a platform where time_t is unsigned, correct the way that microdesc_add_to_cache() handles negative time arguments. Fixes bug 8042; bugfix on 0.2.3.1-alpha. - Fix various instances of undefined behavior in channeltls.c, tor_memmem(), and eventdns.c that would cause us to construct pointers to memory outside an allocated object. (These invalid pointers were not accessed, but C does not even allow them to exist.) Fixes bug 10363; bugfixes on 0.1.1.1-alpha, 0.1.2.1-alpha, 0.2.0.10-alpha, and 0.2.3.6-alpha. Reported by "bobnomnom". - Use the AddressSanitizer and Ubsan sanitizers (in clang-3.4) to fix some miscellaneous errors in our tests and codebase. Fixes bug 11232. Bugfixes on versions back as far as 0.2.1.11-alpha. - Always check return values for unlink, munmap, UnmapViewOfFile; check strftime return values more often. In some cases all we can do is report a warning, but this may help prevent deeper bugs from going unnoticed. Closes ticket 8787; bugfixes on many, many tor versions. - Fix numerous warnings from the clang "scan-build" static analyzer. Some of these are programming style issues; some of them are false positives that indicated awkward code; some are undefined behavior cases related to constructing (but not using) invalid pointers; some are assumptions about API behavior; some are (harmlessly) logging sizeof(ptr) bytes from a token when sizeof(*ptr) would be correct; and one or two are genuine bugs that weren't reachable from the rest of the program. Fixes bug 8793; bugfixes on many, many tor versions. o Minor bugfixes (node selection): - If ExcludeNodes is set, consider non-excluded hidden service directory servers before excluded ones. Do not consider excluded hidden service directory servers at all if StrictNodes is set. (Previously, we would sometimes decide to connect to those servers, and then realize before we initiated a connection that we had excluded them.) Fixes bug 10722; bugfix on 0.2.0.10-alpha. Reported by "mr-4". - If we set the ExitNodes option but it doesn't include any nodes that have the Exit flag, we would choose not to bootstrap. Now we bootstrap so long as ExitNodes includes nodes which can exit to some port. Fixes bug 10543; bugfix on 0.2.4.10-alpha. o Minor bugfixes (performance): - Avoid a bug where every successful connection made us recompute the flag telling us whether we have sufficient information to build circuits. Previously, we would forget our cached value whenever we successfully opened a channel (or marked a router as running or not running for any other reason), regardless of whether we had previously believed the router to be running. This forced us to run an expensive update operation far too often. Fixes bug 12170; bugfix on 0.1.2.1-alpha. - Avoid using tor_memeq() for checking relay cell integrity. This removes a possible performance bottleneck. Fixes part of bug 12169; bugfix on 0.2.1.31. o Minor bugfixes (platform-specific): - When dumping a malformed directory object to disk, save it in binary mode on Windows, not text mode. Fixes bug 11342; bugfix on 0.2.2.1-alpha. - Don't report failures from make_socket_reuseable() on incoming sockets on OSX: this can happen when incoming connections close early. Fixes bug 10081. o Minor bugfixes (pluggable transports): - Avoid another 60-second delay when starting Tor in a pluggable- transport-using configuration when we already have cached descriptors for our bridges. Fixes bug 11965; bugfix on 0.2.3.6-alpha. o Minor bugfixes (protocol correctness): - When receiving a VERSIONS cell with an odd number of bytes, close the connection immediately since the cell is malformed. Fixes bug 10365; bugfix on 0.2.0.10-alpha. Spotted by "bobnomnom"; fix by "rl1987". o Minor bugfixes (relay, other): - We now drop CREATE cells for already-existent circuit IDs and for zero-valued circuit IDs, regardless of other factors that might otherwise have called for DESTROY cells. Fixes bug 12191; bugfix on 0.0.8pre1. - When rejecting DATA cells for stream_id zero, still count them against the circuit's deliver window so that we don't fail to send a SENDME. Fixes bug 11246; bugfix on 0.2.4.10-alpha. o Minor bugfixes (relay, threading): - Check return code on spawn_func() in cpuworker code, so that we don't think we've spawned a nonworking cpuworker and write junk to it forever. Fix related to bug 4345; bugfix on all released Tor versions. Found by "skruffy". - Use a pthread_attr to make sure that spawn_func() cannot return an error while at the same time launching a thread. Fix related to bug 4345; bugfix on all released Tor versions. Reported by "cypherpunks". o Minor bugfixes (relays and bridges): - Avoid crashing on a malformed resolv.conf file when running a relay using Libevent 1. Fixes bug 8788; bugfix on 0.1.1.23. - Non-exit relays no longer launch mock DNS requests to check for DNS hijacking. This has been unnecessary since 0.2.1.7-alpha, when non-exit relays stopped servicing DNS requests. Fixes bug 965; bugfix on 0.2.1.7-alpha. Patch from Matt Pagan. - Bridges now report complete directory request statistics. Related to bug 5824; bugfix on 0.2.2.1-alpha. - Bridges now never collect statistics that were designed for relays. Fixes bug 5824; bugfix on 0.2.3.8-alpha. o Minor bugfixes (testing): - Fix all valgrind warnings produced by the unit tests. There were over a thousand memory leak warnings previously, mostly produced by forgetting to free things in the unit test code. Fixes bug 11618, bugfixes on many versions of Tor. o Minor bugfixes (tor-fw-helper): - Give a correct log message when tor-fw-helper fails to launch. (Previously, we would say something like "tor-fw-helper sent us a string we could not parse".) Fixes bug 9781; bugfix on 0.2.4.2-alpha. o Minor bugfixes (trivial memory leaks): - Fix a small memory leak when signing a directory object. Fixes bug 11275; bugfix on 0.2.4.13-alpha. - Resolve some memory leaks found by coverity in the unit tests, on exit in tor-gencert, and on a failure to compute digests for our own keys when generating a v3 networkstatus vote. These leaks should never have affected anyone in practice. o Code simplification and refactoring: - Remove some old fallback code designed to keep Tor clients working in a network with only two working relays. Elsewhere in the code we have long since stopped supporting such networks, so there wasn't much point in keeping it around. Addresses ticket 9926. - Reject 0-length EXTEND2 cells more explicitly. Fixes bug 10536; bugfix on 0.2.4.8-alpha. Reported by "cypherpunks". - Extract the common duplicated code for creating a subdirectory of the data directory and writing to a file in it. Fixes ticket 4282; patch from Peter Retzlaff. - Since OpenSSL 0.9.7, the i2d_*() functions support allocating output buffer. Avoid calling twice: i2d_RSAPublicKey(), i2d_DHparams(), i2d_X509(), and i2d_PublicKey(). Resolves ticket 5170. - Add a set of accessor functions for the circuit timeout data structure. Fixes ticket 6153; patch from "piet". - Clean up exit paths from connection_listener_new(). Closes ticket 8789. Patch from Arlo Breault. - Since we rely on OpenSSL 0.9.8 now, we can use EVP_PKEY_cmp() and drop our own custom pkey_eq() implementation. Fixes bug 9043. - Use a doubly-linked list to implement the global circuit list. Resolves ticket 9108. Patch from Marek Majkowski. - Remove contrib/id_to_fp.c since it wasn't used anywhere. - Remove constants and tests for PKCS1 padding; it's insecure and shouldn't be used for anything new. Fixes bug 8792; patch from Arlo Breault. - Remove instances of strcpy() from the unit tests. They weren't hurting anything, since they were only in the unit tests, but it's embarassing to have strcpy() in the code at all, and some analysis tools don't like it. Fixes bug 8790; bugfix on 0.2.3.6-alpha and 0.2.3.8-alpha. Patch from Arlo Breault. - Remove is_internal_IP() function. Resolves ticket 4645. - Remove unused function circuit_dump_by_chan from circuitlist.c. Closes issue 9107; patch from "marek". - Change our use of the ENUM_BF macro to avoid declarations that confuse Doxygen. - Get rid of router->address, since in all cases it was just the string representation of router->addr. Resolves ticket 5528. o Documentation: - Adjust the URLs in the README to refer to the new locations of several documents on the website. Fixes bug 12830. Patch from Matt Pagan. - Document 'reject6' and 'accept6' ExitPolicy entries. Resolves ticket 12878. - Update manpage to describe some of the files you can expect to find in Tor's DataDirectory. Addresses ticket 9839. - Clean up several option names in the manpage to match their real names, add the missing documentation for a couple of testing and directory authority options, remove the documentation for a V2-directory fetching option that no longer exists. Resolves ticket 11634. - Correct the documenation so that it lists the correct directory for the stats files. (They are in a subdirectory called "stats", not "status".) - In the manpage, move more authority-only options into the directory authority section so that operators of regular directory caches don't get confused. - Fix the layout of the SOCKSPort flags in the manpage. Fixes bug 11061; bugfix on 0.2.4.7-alpha. - Resolve warnings from Doxygen. - Document in the manpage that "KBytes" may also be written as "kilobytes" or "KB", that "Kbits" may also be written as "kilobits", and so forth. Closes ticket 9222. - Document that the ClientOnly config option overrides ORPort. Our old explanation made ClientOnly sound as though it did nothing at all. Resolves bug 9059. - Explain that SocksPolicy, DirPolicy, and similar options don't take port arguments. Fixes the other part of ticket 11108. - Fix a comment about the rend_server_descriptor_t.protocols field to more accurately describe its range. Also, make that field unsigned, to more accurately reflect its usage. Fixes bug 9099; bugfix on 0.2.1.5-alpha. - Fix the manpage's description of HiddenServiceAuthorizeClient: the maximum client name length is 16, not 19. Fixes bug 11118; bugfix on 0.2.1.6-alpha. o Package cleanup: - The contrib directory has been sorted and tidied. Before, it was an unsorted dumping ground for useful and not-so-useful things. Now, it is divided based on functionality, and the items which seemed to be nonfunctional or useless have been removed. Resolves ticket 8966; based on patches from "rl1987". o Removed code and features: - Clients now reject any directory authority certificates lacking a dir-key-crosscert element. These have been included since 0.2.1.9-alpha, so there's no real reason for them to be optional any longer. Completes proposal 157. Resolves ticket 10162. - Remove all code that existed to support the v2 directory system, since there are no longer any v2 directory authorities. Resolves ticket 10758. - Remove the HSAuthoritativeDir and AlternateHSAuthority torrc options, which were used for designating authorities as "Hidden service authorities". There has been no use of hidden service authorities since 0.2.2.1-alpha, when we stopped uploading or downloading v0 hidden service descriptors. Fixes bug 10881; also part of a fix for bug 10841. - Remove /tor/dbg-stability.txt URL that was meant to help debug WFU and MTBF calculations, but that nobody was using. Fixes bug 11742. - The TunnelDirConns and PreferTunnelledDirConns options no longer exist; tunneled directory connections have been available since 0.1.2.5-alpha, and turning them off is not a good idea. This is a brute-force fix for 10849, where "TunnelDirConns 0" would break hidden services. - Remove all code for the long unused v1 directory protocol. Resolves ticket 11070. - Remove all remaining code related to version-0 hidden service descriptors: they have not been in use since 0.2.2.1-alpha. Fixes the rest of bug 10841. - Remove migration code from when we renamed the "cached-routers" file to "cached-descriptors" back in 0.2.0.8-alpha. This incidentally resolves ticket 6502 by cleaning up the related code a bit. Patch from Akshay Hebbar. o Test infrastructure: - Tor now builds each source file in two modes: a mode that avoids exposing identifiers needlessly, and another mode that exposes more identifiers for testing. This lets the compiler do better at optimizing the production code, while enabling us to take more radical measures to let the unit tests test things. - The production builds no longer include functions used only in the unit tests; all functions exposed from a module only for unit-testing are now static in production builds. - Add an --enable-coverage configuration option to make the unit tests (and a new src/or/tor-cov target) to build with gcov test coverage support. - Update to the latest version of tinytest. - Improve the tinytest implementation of string operation tests so that comparisons with NULL strings no longer crash the tests; they now just fail, normally. Fixes bug 9004; bugfix on 0.2.2.4-alpha. - New macros in test.h to simplify writing mock-functions for unit tests. Part of ticket 11507. Patch from Dana Koch. - We now have rudimentary function mocking support that our unit tests can use to test functions in isolation. Function mocking lets the tests temporarily replace a function's dependencies with stub functions, so that the tests can check the function without invoking the other functions it calls. o Testing: - Complete tests for the status.c module. Resolves ticket 11507. Patch from Dana Koch. - Add more unit tests for the <circid,channel>->circuit map, and the destroy-cell-tracking code to fix bug 7912. - Unit tests for failing cases of the TAP onion handshake. - More unit tests for address-manipulation functions. o Distribution (systemd): - Include a tor.service file in contrib/dist for use with systemd. Some distributions will be able to use this file unmodified; others will need to tweak it, or write their own. Patch from Jamie Nguyen; resolves ticket 8368. - Verify configuration file via ExecStartPre in the systemd unit file. Patch from intrigeri; resolves ticket 12730. - Explicitly disable RunAsDaemon in the systemd unit file. Our current systemd unit uses "Type = simple", so systemd does not expect tor to fork. If the user has "RunAsDaemon 1" in their torrc, then things won't work as expected. This is e.g. the case on Debian (and derivatives), since there we pass "--defaults-torrc /usr/share/tor/tor-service-defaults-torrc" (that contains "RunAsDaemon 1") by default. 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Tor Browser 3.6.6 and Tor 0.2.4.24 are released
by Roger Dingledine 27 Sep '14

27 Sep '14

The sixth pointfix release of the Tor Browser 3.6 series is available from the Tor Browser Project page and also from our distribution directory: https://www.torproject.org/download/download-easy.html https://www.torproject.org/dist/torbrowser/3.6.6/ This release features important security updates to Firefox: https://www.mozilla.org/security/known-vulnerabilities/firefoxESR.html#fire… Here is the complete changelog for 3.6.6: All Platforms Update Tor to tor-0.2.4.24 Update Firefox to 24.8.1esr Update NoScript to 2.6.8.42 Update HTTPS Everywhere to 4.0.1 Bug 12998: Prevent intermediate certs from being written to disk Update Torbutton to 1.6.12.3 Bug 13091: Use "Tor Browser" everywhere Bug 10804: Workaround fix for some cases of startup hang Linux Bug 9150: Make RPATH unavailable on Tor binary. ----------------------------------------------------------------------- Tor 0.2.4.24 fixes a bug that affects consistency and speed when connecting to hidden services, and it updates the location of one of the directory authorities. Changes in version 0.2.4.24 - 2014-09-22 o Major bugfixes: - Clients now send the correct address for their chosen rendezvous point when trying to access a hidden service. They used to send the wrong address, which would still work some of the time because they also sent the identity digest of the rendezvous point, and if the hidden service happened to try connecting to the rendezvous point from a relay that already had a connection open to it, the relay would reuse that connection. Now connections to hidden services should be more robust and faster. Also, this bug meant that clients were leaking to the hidden service whether they were on a little-endian (common) or big-endian (rare) system, which for some users might have reduced their anonymity. Fixes bug 13151; bugfix on 0.2.1.5-alpha. o Directory authority changes: - Change IP address for gabelmoo (v3 directory authority). o Minor features (geoip): - Update geoip and geoip6 to the August 7 2014 Maxmind GeoLite2 Country database.

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Tor security advisory: "relay early" traffic confirmation attack
by Roger Dingledine 30 Jul '14

30 Jul '14

SUMMARY: On July 4 2014 we found a group of relays that we assume were trying to deanonymize users. They appear to have been targeting people who operate or access Tor hidden services. The attack involved modifying Tor protocol headers to do traffic confirmation attacks. The attacking relays joined the network on January 30 2014, and we removed them from the network on July 4. While we don't know when they started doing the attack, users who operated or accessed hidden services from early February through July 4 should assume they were affected. Unfortunately, it's still unclear what "affected" includes. We know the attack looked for users who fetched hidden service descriptors, but the attackers likely were not able to see any application-level traffic (e.g. what pages were loaded or even whether users visited the hidden service they looked up). The attack probably also tried to learn who published hidden service descriptors, which would allow the attackers to learn the location of that hidden service. In theory the attack could also be used to link users to their destinations on normal Tor circuits too, but we found no evidence that the attackers operated any exit relays, making this attack less likely. And finally, we don't know how much data the attackers kept, and due to the way the attack was deployed (more details below), their protocol header modifications might have aided other attackers in deanonymizing users too. Relays should upgrade to a recent Tor release (0.2.4.23 or 0.2.5.6-alpha), to close the particular protocol vulnerability the attackers used -- but remember that preventing traffic confirmation in general remains an open research problem. Clients that upgrade (once new Tor Browser releases are ready) will take another step towards limiting the number of entry guards that are in a position to see their traffic, thus reducing the damage from future attacks like this one. Hidden service operators should consider changing the location of their hidden service. THE TECHNICAL DETAILS: We believe they used a combination of two classes of attacks: a traffic confirmation attack and a Sybil attack. A traffic confirmation attack is possible when the attacker controls or observes the relays on both ends of a Tor circuit and then compares traffic timing, volume, or other characteristics to conclude that the two relays are indeed on the same circuit. If the first relay in the circuit (called the "entry guard") knows the IP address of the user, and the last relay in the circuit knows the resource or destination she is accessing, then together they can deanonymize her. You can read more about traffic confirmation attacks, including pointers to many research papers, at this blog post from 2009: https://blog.torproject.org/blog/one-cell-enough The particular confirmation attack they used was an active attack where the relay on one end injects a signal into the Tor protocol headers, and then the relay on the other end reads the signal. These attacking relays were stable enough to get the HSDir ("suitable for hidden service directory") and Guard ("suitable for being an entry guard") consensus flags: https://gitweb.torproject.org/torspec.git/blob/HEAD:/dir-spec.txt#l1775 Then they injected the signal whenever they were used as a hidden service directory, and looked for an injected signal whenever they were used as an entry guard. The way they injected the signal was by sending sequences of "relay" vs "relay early" commands down the circuit, to encode the message they want to send. For background, Tor has two types of cells: link cells, which are intended for the adjacent relay in the circuit, and relay cells, which are passed to the other end of the circuit. https://gitweb.torproject.org/torspec.git/blob/HEAD:/tor-spec.txt#l364 In 2008 we added a new kind of relay cell, called a "relay early" cell, which is used to prevent people from building very long paths in the Tor network (very long paths can be used to induce congestion and aid in breaking anonymity): http://freehaven.net/anonbib/#congestion-longpaths https://gitweb.torproject.org/torspec.git/blob/HEAD:/proposals/110-avoid-in… But the fix for infinite-length paths introduced a problem with accessing hidden services: https://trac.torproject.org/projects/tor/ticket/1038 and one of the side effects of our fix for bug 1038 was that while we limit the number of outbound (away from the client) "relay early" cells on a circuit, we don't limit the number of inbound (towards the client) relay early cells: https://lists.torproject.org/pipermail/tor-commits/2009-July/014679.html So in summary, when Tor clients contacted an attacking relay in its role as a Hidden Service Directory to publish or retrieve a hidden service descriptor (steps 2 and 3 on https://www.torproject.org/docs/hidden-services) that relay would send the hidden service name (encoded as a pattern of relay and relay-early cells) back down the circuit. Other attacking relays, when they get chosen for the first hop of a circuit, would look for inbound relay-early cells (since nobody else sends them) and would thus learn which clients requested information about a hidden service. There are three important points about this attack: A) The attacker encoded the name of the hidden service in the injected signal (as opposed to, say, sending a random number and keeping a local list mapping random number to hidden service name). The encoded signal is encrypted as it is sent over the TLS channel between relays. However, this signal would be easy to read and interpret by anybody who runs a relay and receives the encoded traffic. And we might also worry about a global adversary (e.g. a large intelligence agency) that records Internet traffic at the entry guards and then tries to break Tor's link encryption. The way this attack was performed weakens Tor's anonymity against these other potential attackers too -- either while it was happening or after the fact if they have traffic logs. So if the attack was a research project (i.e. not intentionally malicious), it was deployed in an irresponsible way because it puts users at risk indefinitely into the future. (This concern is in addition to the general issue that it's probably unwise from a legal perspective for researchers to attack real users by modifying their traffic on one end and wiretapping it on the other. Tools like Shadow are great for testing Tor research ideas out in the lab: http://shadow.github.io/ ) B) This protocol header signal injection attack is actually pretty neat from a research perspective, in that it's a bit different from previous tagging attacks which targeted the application-level payload. Previous tagging attacks modified the payload at the entry guard, and then looked for a modified payload at the exit relay (which can see the decrypted payload). Those attacks don't work in the other direction (from the exit relay back towards the client), because the payload is still encrypted at the entry guard. But because this new approach modifies ("tags") the cell headers rather than the payload, every relay in the path can see the tag. C) We should remind readers that while this particular variant of the traffic confirmation attack allows high-confidence and efficient correlation, the general class of passive (statistical) traffic confirmation attacks remains unsolved and would likely have worked just fine here. So the good news is traffic confirmation attacks aren't new or surprising, but the bad news is that they still work. See https://blog.torproject.org/blog/one-cell-enough for more discussion. Then the second class of attack they used, in conjunction with their traffic confirmation attack, was a standard Sybil attack -- they signed up around 115 fast non-exit relays, all running on 50.7.0.0/16 or 204.45.0.0/16. Together these relays summed to about 6.4% of the Guard capacity in the network. Then, in part because of our current guard rotation parameters: https://blog.torproject.org/blog/improving-tors-anonymity-changing-guard-pa… these relays became entry guards for a significant chunk of users over their five months of operation. We actually noticed these relays when they joined the network, since the DocTor scanner reported them: https://lists.torproject.org/pipermail/tor-consensus-health/2014-January/00… https://gitweb.torproject.org/doctor.git We considered the set of new relays at the time, and made a decision that it wasn't that large a fraction of the network. It's clear there's room for improvement in terms of how to let the Tor network grow while also ensuring we maintain social connections with the operators of all large groups of relays. (In general having a widely diverse set of relay locations and relay operators, yet not allowing any bad relays in, seems like a hard problem; on the other hand our detection scripts did notice them in this case, so there's hope for a better solution here.) In response, we've taken the following short-term steps: 1) Removed the attacking relays from the network. 2) Put out a software update for relays to prevent "relay early" cells from being used this way. 3) Put out a software update that will (once enough clients have upgraded) let us tell clients to move to using one entry guard rather than three, to reduce exposure to relays over time. 4) Clients can tell whether they've received a relay or relay-cell. For expert users, the new Tor version warns you in your logs if a relay on your path injects any relay-early cells: look for the phrase "Received an inbound RELAY_EARLY cell". The following longer-term research areas remain: 5) Further growing the Tor network and diversity of relay operators, which will reduce the impact from an adversary of a given size. 6) Exploring better mechanisms, e.g. social connections, to limit the impact from a malicious set of relays. We've also formed a group to pay more attention to suspicious relays in the network: https://blog.torproject.org/blog/how-report-bad-relays 7) Further reducing exposure to guards over time, perhaps by extending the guard rotation lifetime: https://blog.torproject.org/blog/lifecycle-of-a-new-relay https://blog.torproject.org/blog/improving-tors-anonymity-changing-guard-pa… 8) Better understanding statistical traffic correlation attacks and whether padding or other approaches can mitigate them. 9) Improving the hidden service design, including making it harder for relays serving as hidden service directory points to learn what hidden service address they're handling: https://blog.torproject.org/blog/hidden-services-need-some-love OPEN QUESTIONS: Q1) Was this the Black Hat 2014 talk that got canceled recently? Q2) Did we find all the malicious relays? Q3) Did the malicious relays inject the signal at any points besides the HSDir position? Q4) What data did the attackers keep, and are they going to destroy it? How have they protected the data (if any) while storing it? Great questions. We spent several months trying to extract information from the researchers who were going to give the Black Hat talk, and eventually we did get some hints from them about how "relay early" cells could be used for traffic confirmation attacks, which is how we started looking for the attacks in the wild. They haven't answered our emails lately, so we don't know for sure, but it seems likely that the answer to Q1 is "yes". In fact, we hope they *were* the ones doing the attacks, since otherwise it means somebody else was. We don't yet know the answers to Q2, Q3, or Q4.

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Tor 0.2.4.23 is released
by Roger Dingledine 30 Jul '14

30 Jul '14

Tor 0.2.4.23 brings us a big step closer to slowing down the risk from guard rotation, and also backports several important fixes from the Tor 0.2.5 alpha release series. Changes in version 0.2.4.23 - 2014-07-28 o Major features: - Clients now look at the "usecreatefast" consensus parameter to decide whether to use CREATE_FAST or CREATE cells for the first hop of their circuit. This approach can improve security on connections where Tor's circuit handshake is stronger than the available TLS connection security levels, but the tradeoff is more computational load on guard relays. Implements proposal 221. Resolves ticket 9386. - Make the number of entry guards configurable via a new NumEntryGuards consensus parameter, and the number of directory guards configurable via a new NumDirectoryGuards consensus parameter. Implements ticket 12688. o Major bugfixes: - Fix a bug in the bounds-checking in the 32-bit curve25519-donna implementation that caused incorrect results on 32-bit implementations when certain malformed inputs were used along with a small class of private ntor keys. This bug does not currently appear to allow an attacker to learn private keys or impersonate a Tor server, but it could provide a means to distinguish 32-bit Tor implementations from 64-bit Tor implementations. Fixes bug 12694; bugfix on 0.2.4.8-alpha. Bug found by Robert Ransom; fix from Adam Langley. o Minor bugfixes: - Warn and drop the circuit if we receive an inbound 'relay early' cell. Those used to be normal to receive on hidden service circuits due to bug 1038, but the buggy Tor versions are long gone from the network so we can afford to resume watching for them. Resolves the rest of bug 1038; bugfix on 0.2.1.19. - Correct a confusing error message when trying to extend a circuit via the control protocol but we don't know a descriptor or microdescriptor for one of the specified relays. Fixes bug 12718; bugfix on 0.2.3.1-alpha. - Avoid an illegal read from stack when initializing the TLS module using a version of OpenSSL without all of the ciphers used by the v2 link handshake. Fixes bug 12227; bugfix on 0.2.4.8-alpha. Found by "starlight". o Minor features: - Update geoip and geoip6 to the July 10 2014 Maxmind GeoLite2 Country database.

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[ANN] Tor 0.2.4.22 is released (and so were 0.2.4.20 and 0.2.4.21)
by Nick Mathewson 04 Jun '14

04 Jun '14

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello, all! This is a slightly belated announcement for the release of 0.2.4.22. I'm including the release notes for Tor 0.2.4.20 and Tor 0.2.4.21 as well, since apparently they never made it onto this list. I've enlisted help from Colin to make sure that future stable release announcements make it to this list in a more timely manner (ideally, as soon as packages are built). TorBrowser releases will typically lag a little, as they follow their own release schedule. (Alpha releases will still be announced on tor-talk only.) Changes in version 0.2.4.22 - 2014-05-16 Tor 0.2.4.22 backports numerous high-priority fixes from the Tor 0.2.5 alpha release series. These include blocking all authority signing keys that may have been affected by the OpenSSL "heartbleed" bug, choosing a far more secure set of TLS ciphersuites by default, closing a couple of memory leaks that could be used to run a target relay out of RAM, and several others. o Major features (security, backport from 0.2.5.4-alpha): - Block authority signing keys that were used on authorities vulnerable to the "heartbleed" bug in OpenSSL (CVE-2014-0160). (We don't have any evidence that these keys _were_ compromised; we're doing this to be prudent.) Resolves ticket 11464. o Major bugfixes (security, OOM): - Fix a memory leak that could occur if a microdescriptor parse fails during the tokenizing step. This bug could enable a memory exhaustion attack by directory servers. Fixes bug 11649; bugfix on 0.2.2.6-alpha. o Major bugfixes (TLS cipher selection, backport from 0.2.5.4-alpha): - The relay ciphersuite list is now generated automatically based on uniform criteria, and includes all OpenSSL ciphersuites with acceptable strength and forward secrecy. Previously, we had left some perfectly fine ciphersuites unsupported due to omission or typo. Resolves bugs 11513, 11492, 11498, 11499. Bugs reported by 'cypherpunks'. Bugfix on 0.2.4.8-alpha. - Relays now trust themselves to have a better view than clients of which TLS ciphersuites are better than others. (Thanks to bug 11513, the relay list is now well-considered, whereas the client list has been chosen mainly for anti-fingerprinting purposes.) Relays prefer: AES over 3DES; then ECDHE over DHE; then GCM over CBC; then SHA384 over SHA256 over SHA1; and last, AES256 over AES128. Resolves ticket 11528. - Clients now try to advertise the same list of ciphersuites as Firefox 28. This change enables selection of (fast) GCM ciphersuites, disables some strange old ciphers, and stops advertising the ECDH (not to be confused with ECDHE) ciphersuites. Resolves ticket 11438. o Minor bugfixes (configuration, security): - When running a hidden service, do not allow TunneledDirConns 0: trying to set that option together with a hidden service would otherwise prevent the hidden service from running, and also make it publish its descriptors directly over HTTP. Fixes bug 10849; bugfix on 0.2.1.1-alpha. o Minor bugfixes (controller, backport from 0.2.5.4-alpha): - Avoid sending a garbage value to the controller when a circuit is cannibalized. Fixes bug 11519; bugfix on 0.2.3.11-alpha. o Minor bugfixes (exit relay, backport from 0.2.5.4-alpha): - Stop leaking memory when we successfully resolve a PTR record. Fixes bug 11437; bugfix on 0.2.4.7-alpha. o Minor bugfixes (bridge client, backport from 0.2.5.4-alpha): - Avoid 60-second delays in the bootstrapping process when Tor is launching for a second time while using bridges. Fixes bug 9229; bugfix on 0.2.0.3-alpha. o Minor bugfixes (relays and bridges, backport from 0.2.5.4-alpha): - Give the correct URL in the warning message when trying to run a relay on an ancient version of Windows. Fixes bug 9393. o Minor bugfixes (compilation): - Fix a compilation error when compiling with --disable-curve25519. Fixes bug 9700; bugfix on 0.2.4.17-rc. o Minor bugfixes: - Downgrade the warning severity for the the "md was still referenced 1 node(s)" warning. Tor 0.2.5.4-alpha has better code for trying to diagnose this bug, and the current warning in earlier versions of tor achieves nothing useful. Addresses warning from bug 7164. o Minor features (log verbosity, backport from 0.2.5.4-alpha): - When we run out of usable circuit IDs on a channel, log only one warning for the whole channel, and describe how many circuits there were on the channel. Fixes part of ticket 11553. o Minor features (security, backport from 0.2.5.4-alpha): - Decrease the lower limit of MaxMemInCellQueues to 256 MBytes (but leave the default at 8GBytes), to better support Raspberry Pi users. Fixes bug 9686; bugfix on 0.2.4.14-alpha. o Documentation (backport from 0.2.5.4-alpha): - Correctly document that we search for a system torrc file before looking in ~/.torrc. Fixes documentation side of 9213; bugfix on 0.2.3.18-rc. Changes in version 0.2.4.21 - 2014-02-28 Tor 0.2.4.21 further improves security against potential adversaries who find breaking 1024-bit crypto doable, and backports several stability and robustness patches from the 0.2.5 branch. o Major features (client security): - When we choose a path for a 3-hop circuit, make sure it contains at least one relay that supports the NTor circuit extension handshake. Otherwise, there is a chance that we're building a circuit that's worth attacking by an adversary who finds breaking 1024-bit crypto doable, and that chance changes the game theory. Implements ticket 9777. o Major bugfixes: - Do not treat streams that fail with reason END_STREAM_REASON_INTERNAL as indicating a definite circuit failure, since it could also indicate an ENETUNREACH connection error. Fixes part of bug 10777; bugfix on 0.2.4.8-alpha. o Code simplification and refactoring: - Remove data structures which were introduced to implement the CellStatistics option: they are now redundant with the new timestamp field in the regular packed_cell_t data structure, which we did in 0.2.4.18-rc in order to resolve bug 9093. Resolves ticket 10870. o Minor features: - Always clear OpenSSL bignums before freeing them -- even bignums that don't contain secrets. Resolves ticket 10793. Patch by Florent Daigniere. - Build without warnings under clang 3.4. (We have some macros that define static functions only some of which will get used later in the module. Starting with clang 3.4, these give a warning unless the unused attribute is set on them.) Resolves ticket 10904. - Update geoip and geoip6 files to the February 7 2014 Maxmind GeoLite2 Country database. o Minor bugfixes: - Set the listen() backlog limit to the largest actually supported on the system, not to the value in a header file. Fixes bug 9716; bugfix on every released Tor. - Treat ENETUNREACH, EACCES, and EPERM connection failures at an exit node as a NOROUTE error, not an INTERNAL error, since they can apparently happen when trying to connect to the wrong sort of netblocks. Fixes part of bug 10777; bugfix on 0.1.0.1-rc. - Fix build warnings about missing "a2x" comment when building the manpages from scratch on OpenBSD; OpenBSD calls it "a2x.py". Fixes bug 10929; bugfix on 0.2.2.9-alpha. Patch from Dana Koch. - Avoid a segfault on SIGUSR1, where we had freed a connection but did not entirely remove it from the connection lists. Fixes bug 9602; bugfix on 0.2.4.4-alpha. - Fix a segmentation fault in our benchmark code when running with Fedora's OpenSSL package, or any other OpenSSL that provides ECDH but not P224. Fixes bug 10835; bugfix on 0.2.4.8-alpha. - Turn "circuit handshake stats since last time" log messages into a heartbeat message. Fixes bug 10485; bugfix on 0.2.4.17-rc. o Documentation fixes: - Document that all but one DirPort entry must have the NoAdvertise flag set. Fixes bug 10470; bugfix on 0.2.3.3-alpha / 0.2.3.16-alpha. Changes in version 0.2.4.20 - 2013-12-22 Tor 0.2.4.20 fixes potentially poor random number generation for users who 1) use OpenSSL 1.0.0 or later, 2) set "HardwareAccel 1" in their torrc file, 3) have "Sandy Bridge" or "Ivy Bridge" Intel processors, and 4) have no state file in their DataDirectory (as would happen on first start). Users who generated relay or hidden service identity keys in such a situation should discard them and generate new ones. This release also fixes a logic error that caused Tor clients to build many more preemptive circuits than they actually need. o Major bugfixes: - Do not allow OpenSSL engines to replace the PRNG, even when HardwareAccel is set. The only default builtin PRNG engine uses the Intel RDRAND instruction to replace the entire PRNG, and ignores all attempts to seed it with more entropy. That's cryptographically stupid: the right response to a new alleged entropy source is never to discard all previously used entropy sources. Fixes bug 10402; works around behavior introduced in OpenSSL 1.0.0. Diagnosis and investigation thanks to "coderman" and "rl1987". - Fix assertion failure when AutomapHostsOnResolve yields an IPv6 address. Fixes bug 10465; bugfix on 0.2.4.7-alpha. - Avoid launching spurious extra circuits when a stream is pending. This fixes a bug where any circuit that _wasn't_ unusable for new streams would be treated as if it were, causing extra circuits to be launched. Fixes bug 10456; bugfix on 0.2.4.12-alpha. o Minor bugfixes: - Avoid a crash bug when starting with a corrupted microdescriptor cache file. Fixes bug 10406; bugfix on 0.2.2.6-alpha. - If we fail to dump a previously cached microdescriptor to disk, avoid freeing duplicate data later on. Fixes bug 10423; bugfix on 0.2.4.13-alpha. Spotted by "bobnomnom". -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQGVAwUBU45IaJEDl9iNKTGaAQKCvAv8CFVTBvwsHap8IpBT48S/sdybN0uL8L7N 1axQbgAbuTyyyskZaOTv/pp/4FvvOJ0ulCZfyrsXV7jQhsUNm1Ri9phWob2/sEpx 6Io9AVxw9W16mzduqlmxkdiVmvQNN17XTuPaYcjBtN2bbDGyrG6XtYjo03Lu3HUV xgKuaJR7eiked8G44slbccz80V1zmKq75YD4gFJgyBBNoS/0tmjh2zmjaE+7TeBq jEJyedFPVhhGHWg2PruDLeSgfKTIwA8KtJwAmJ7JwKNSX4LTFGz7MZrX77QdnZ3D FRDUuvGMVq6p5QGfsx59B9Uc6o8ox6UfnXYEqtzP9fDKPRvFNU7FqSV7Siu54Bk6 f/aY00IC05etz4X6t2NOtSCKAu7/Abd7zbYRLaW/v67/r6iaR6r/LVAILgJZA8jw acZGBaVov4ta/5sJcWLx/6iCD1VxtGkgk6TH399b1EGn9SFO4Exp5sGMLc4qiLEk 3hP+/YEYNx+yDz1IkupuwZDHa4iQtefh =du7v -----END PGP SIGNATURE-----

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