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diff --git a/ReleaseNotes b/ReleaseNotes index d6adbe5f9b..1e56ffaf89 100644 --- a/ReleaseNotes +++ b/ReleaseNotes @@ -2,6 +2,1415 @@ This document summarizes new features and bugfixes in each stable release of Tor. If you want to see more detailed descriptions of the changes in each development snapshot, see the ChangeLog file. +Changes in version 0.3.0.8 - 2017-06-08 + Tor 0.3.0.8 fixes a pair of bugs that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-004 and TROVE-2017-005. + + Tor 0.3.0.8 also includes fixes for several key management bugs + that sometimes made relays unreliable, as well as several other + bugfixes described below. + + o Major bugfixes (hidden service, relay, security, backport + from 0.3.1.3-alpha): + - Fix a remotely triggerable assertion failure when a hidden service + handles a malformed BEGIN cell. Fixes bug 22493, tracked as + TROVE-2017-004 and as CVE-2017-0375; bugfix on 0.3.0.1-alpha. + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Major bugfixes (relay, link handshake, backport from 0.3.1.3-alpha): + - When performing the v3 link handshake on a TLS connection, report + that we have the x509 certificate that we actually used on that + connection, even if we have changed certificates since that + connection was first opened. Previously, we would claim to have + used our most recent x509 link certificate, which would sometimes + make the link handshake fail. Fixes one case of bug 22460; bugfix + on 0.2.3.6-alpha. + + o Major bugfixes (relays, key management, backport from 0.3.1.3-alpha): + - Regenerate link and authentication certificates whenever the key + that signs them changes; also, regenerate link certificates + whenever the signed key changes. Previously, these processes were + only weakly coupled, and we relays could (for minutes to hours) + wind up with an inconsistent set of keys and certificates, which + other relays would not accept. Fixes two cases of bug 22460; + bugfix on 0.3.0.1-alpha. + - When sending an Ed25519 signing->link certificate in a CERTS cell, + send the certificate that matches the x509 certificate that we + used on the TLS connection. Previously, there was a race condition + if the TLS context rotated after we began the TLS handshake but + before we sent the CERTS cell. Fixes a case of bug 22460; bugfix + on 0.3.0.1-alpha. + + o Major bugfixes (hidden service v3, backport from 0.3.1.1-alpha): + - Stop rejecting v3 hidden service descriptors because their size + did not match an old padding rule. Fixes bug 22447; bugfix on + tor-0.3.0.1-alpha. + + o Minor features (fallback directory list, backport from 0.3.1.3-alpha): + - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in + December 2016 (of which ~126 were still functional) with a list of + 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May + 2017. Resolves ticket 21564. + + o Minor bugfixes (configuration, backport from 0.3.1.1-alpha): + - Do not crash when starting with LearnCircuitBuildTimeout 0. Fixes + bug 22252; bugfix on 0.2.9.3-alpha. + + o Minor bugfixes (correctness, backport from 0.3.1.3-alpha): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + + o Minor bugfixes (link handshake, backport from 0.3.1.3-alpha): + - Lower the lifetime of the RSA->Ed25519 cross-certificate to six + months, and regenerate it when it is within one month of expiring. + Previously, we had generated this certificate at startup with a + ten-year lifetime, but that could lead to weird behavior when Tor + was started with a grossly inaccurate clock. Mitigates bug 22466; + mitigation on 0.3.0.1-alpha. + + o Minor bugfixes (memory leak, directory authority, backport from + 0.3.1.2-alpha): + - When directory authorities reject a router descriptor due to + keypinning, free the router descriptor rather than leaking the + memory. Fixes bug 22370; bugfix on 0.2.7.2-alpha. + + +Changes in version 0.2.9.11 - 2017-06-08 + Tor 0.2.9.11 backports a fix for a bug that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-005. (Versions before 0.3.0 + are not affected by TROVE-2017-004.) + + Tor 0.2.9.11 also backports fixes for several key management bugs + that sometimes made relays unreliable, as well as several other + bugfixes described below. + + o Major bugfixes (hidden service, relay, security, backport + from 0.3.1.3-alpha): + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Major bugfixes (relay, link handshake, backport from 0.3.1.3-alpha): + - When performing the v3 link handshake on a TLS connection, report + that we have the x509 certificate that we actually used on that + connection, even if we have changed certificates since that + connection was first opened. Previously, we would claim to have + used our most recent x509 link certificate, which would sometimes + make the link handshake fail. Fixes one case of bug 22460; bugfix + on 0.2.3.6-alpha. + + o Minor features (fallback directory list, backport from 0.3.1.3-alpha): + - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in + December 2016 (of which ~126 were still functional) with a list of + 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May + 2017. Resolves ticket 21564. + + o Minor features (future-proofing, backport from 0.3.0.7): + - Tor no longer refuses to download microdescriptors or descriptors if + they are listed as "published in the future". This change will + eventually allow us to stop listing meaningful "published" dates + in microdescriptor consensuses, and thereby allow us to reduce the + resources required to download consensus diffs by over 50%. + Implements part of ticket 21642; implements part of proposal 275. + + o Minor features (directory authorities, backport from 0.3.0.4-rc) + - Directory authorities now reject relays running versions + 0.2.9.1-alpha through 0.2.9.4-alpha, because those relays + suffer from bug 20499 and don't keep their consensus cache + up-to-date. Resolves ticket 20509. + + o Minor features (geoip): + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (control port, backport from 0.3.0.6): + - The GETINFO extra-info/digest/<digest> command was broken because + of a wrong base16 decode return value check, introduced when + refactoring that API. Fixes bug 22034; bugfix on 0.2.9.1-alpha. + + o Minor bugfixes (correctness, backport from 0.3.1.3-alpha): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + + o Minor bugfixes (Linux seccomp2 sandbox, backport from 0.3.0.7): + - The getpid() system call is now permitted under the Linux seccomp2 + sandbox, to avoid crashing with versions of OpenSSL (and other + libraries) that attempt to learn the process's PID by using the + syscall rather than the VDSO code. Fixes bug 21943; bugfix + on 0.2.5.1-alpha. + + o Minor bugfixes (memory leak, directory authority, backport + from 0.3.1.2-alpha): + - When directory authorities reject a router descriptor due to + keypinning, free the router descriptor rather than leaking the + memory. Fixes bug 22370; bugfix on 0.2.7.2-alpha. + +Changes in version 0.2.8.14 - 2017-06-08 + Tor 0.2.7.8 backports a fix for a bug that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-005. (Versions before 0.3.0 + are not affected by TROVE-2017-004.) + + o Major bugfixes (hidden service, relay, security): + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Minor features (geoip): + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor features (fallback directory list, backport from 0.3.1.3-alpha): + - Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in + December 2016 (of which ~126 were still functional) with a list of + 151 fallbacks (32 new, 119 unchanged, 58 removed) generated in May + 2017. Resolves ticket 21564. + + o Minor bugfixes (correctness): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + +Changes in version 0.2.7.8 - 2017-06-08 + Tor 0.2.7.8 backports a fix for a bug that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-005. (Versions before 0.3.0 + are not affected by TROVE-2017-004.) + + o Major bugfixes (hidden service, relay, security): + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Minor features (geoip): + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (correctness): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + + +Changes in version 0.2.6.12 - 2017-06-08 + Tor 0.2.6.12 backports a fix for a bug that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-005. (Versions before 0.3.0 + are not affected by TROVE-2017-004.) + + o Major bugfixes (hidden service, relay, security): + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Minor features (geoip): + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (correctness): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + +Changes in version 0.2.5.14 - 2017-06-08 + Tor 0.2.5.14 backports a fix for a bug that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-005. (Versions before 0.3.0 + are not affected by TROVE-2017-004.) + + o Major bugfixes (hidden service, relay, security): + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Minor features (geoip): + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (correctness): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + +Changes in version 0.2.4.29 - 2017-06-08 + Tor 0.2.4.29 backports a fix for a bug that would allow an attacker to + remotely crash a hidden service with an assertion failure. Anyone + running a hidden service should upgrade to this version, or to some + other version with fixes for TROVE-2017-005. (Versions before 0.3.0 + are not affected by TROVE-2017-004.) + + o Major bugfixes (hidden service, relay, security): + - Fix a remotely triggerable assertion failure caused by receiving a + BEGIN_DIR cell on a hidden service rendezvous circuit. Fixes bug + 22494, tracked as TROVE-2017-005 and CVE-2017-0376; bugfix + on 0.2.2.1-alpha. + + o Minor features (geoip): + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (correctness): + - Avoid undefined behavior when parsing IPv6 entries from the geoip6 + file. Fixes bug 22490; bugfix on 0.2.4.6-alpha. + + +Changes in version 0.3.0.7 - 2017-05-15 + Tor 0.3.0.7 fixes a medium-severity security bug in earlier versions + of Tor 0.3.0.x, where an attacker could cause a Tor relay process + to exit. Relays running earlier versions of Tor 0.3.0.x should upgrade; + clients are not affected. + + o Major bugfixes (hidden service directory, security): + - Fix an assertion failure in the hidden service directory code, which + could be used by an attacker to remotely cause a Tor relay process to + exit. Relays running earlier versions of Tor 0.3.0.x should upgrade. + should upgrade. This security issue is tracked as TROVE-2017-002. + Fixes bug 22246; bugfix on 0.3.0.1-alpha. + + o Minor features: + - Update geoip and geoip6 to the May 2 2017 Maxmind GeoLite2 + Country database. + + o Minor features (future-proofing): + - Tor no longer refuses to download microdescriptors or descriptors + if they are listed as "published in the future". This change will + eventually allow us to stop listing meaningful "published" dates + in microdescriptor consensuses, and thereby allow us to reduce the + resources required to download consensus diffs by over 50%. + Implements part of ticket 21642; implements part of proposal 275. + + o Minor bugfixes (Linux seccomp2 sandbox): + - The getpid() system call is now permitted under the Linux seccomp2 + sandbox, to avoid crashing with versions of OpenSSL (and other + libraries) that attempt to learn the process's PID by using the + syscall rather than the VDSO code. Fixes bug 21943; bugfix + on 0.2.5.1-alpha. + + +Changes in version 0.3.0.6 - 2017-04-26 + Tor 0.3.0.6 is the first stable release of the Tor 0.3.0 series. + + With the 0.3.0 series, clients and relays now use Ed25519 keys to + authenticate their link connections to relays, rather than the old + RSA1024 keys that they used before. (Circuit crypto has been + Curve25519-authenticated since 0.2.4.8-alpha.) We have also replaced + the guard selection and replacement algorithm to behave more robustly + in the presence of unreliable networks, and to resist guard- + capture attacks. + + This series also includes numerous other small features and bugfixes, + along with more groundwork for the upcoming hidden-services revamp. + + Per our stable release policy, we plan to support the Tor 0.3.0 + release series for at least the next nine months, or for three months + after the first stable release of the 0.3.1 series: whichever is + longer. If you need a release with long-term support, we recommend + that you stay with the 0.2.9 series. + + Below are the changes since 0.2.9.10. For a list of only the changes + since 0.3.0.5-rc, see the ChangeLog file. + + o Major features (directory authority, security): + - The default for AuthDirPinKeys is now 1: directory authorities + will reject relays where the RSA identity key matches a previously + seen value, but the Ed25519 key has changed. Closes ticket 18319. + + o Major features (guard selection algorithm): + - Tor's guard selection algorithm has been redesigned from the + ground up, to better support unreliable networks and restrictive + sets of entry nodes, and to better resist guard-capture attacks by + hostile local networks. Implements proposal 271; closes + ticket 19877. + + o Major features (next-generation hidden services): + - Relays can now handle v3 ESTABLISH_INTRO cells as specified by + prop224 aka "Next Generation Hidden Services". Service and clients + don't use this functionality yet. Closes ticket 19043. Based on + initial code by Alec Heifetz. + - Relays now support the HSDir version 3 protocol, so that they can + can store and serve v3 descriptors. This is part of the next- + generation onion service work detailled in proposal 224. Closes + ticket 17238. + + o Major features (protocol, ed25519 identity keys): + - Clients now support including Ed25519 identity keys in the EXTEND2 + cells they generate. By default, this is controlled by a consensus + parameter, currently disabled. You can turn this feature on for + testing by setting ExtendByEd25519ID in your configuration. This + might make your traffic appear different than the traffic + generated by other users, however. Implements part of ticket + 15056; part of proposal 220. + - Relays now understand requests to extend to other relays by their + Ed25519 identity keys. When an Ed25519 identity key is included in + an EXTEND2 cell, the relay will only extend the circuit if the + other relay can prove ownership of that identity. Implements part + of ticket 15056; part of proposal 220. + - Relays now use Ed25519 to prove their Ed25519 identities and to + one another, and to clients. This algorithm is faster and more + secure than the RSA-based handshake we've been doing until now. + Implements the second big part of proposal 220; Closes + ticket 15055. + + o Major features (security): + - Change the algorithm used to decide DNS TTLs on client and server + side, to better resist DNS-based correlation attacks like the + DefecTor attack of Greschbach, Pulls, Roberts, Winter, and + Feamster. Now relays only return one of two possible DNS TTL + values, and clients are willing to believe DNS TTL values up to 3 + hours long. Closes ticket 19769. + + o Major bugfixes (client, onion service, also in 0.2.9.9): + - Fix a client-side onion service reachability bug, where multiple + socks requests to an onion service (or a single slow request) + could cause us to mistakenly mark some of the service's + introduction points as failed, and we cache that failure so + eventually we run out and can't reach the service. Also resolves a + mysterious "Remote server sent bogus reason code 65021" log + warning. The bug was introduced in ticket 17218, where we tried to + remember the circuit end reason as a uint16_t, which mangled + negative values. Partially fixes bug 21056 and fixes bug 20307; + bugfix on 0.2.8.1-alpha. + + o Major bugfixes (crash, directory connections): + - Fix a rare crash when sending a begin cell on a circuit whose + linked directory connection had already been closed. Fixes bug + 21576; bugfix on 0.2.9.3-alpha. Reported by Alec Muffett. + + o Major bugfixes (directory authority): + - During voting, when marking a relay as a probable sybil, do not + clear its BadExit flag: sybils can still be bad in other ways + too. (We still clear the other flags.) Fixes bug 21108; bugfix + on 0.2.0.13-alpha. + + o Major bugfixes (DNS): + - Fix a bug that prevented exit nodes from caching DNS records for + more than 60 seconds. Fixes bug 19025; bugfix on 0.2.4.7-alpha. + + o Major bugfixes (IPv6 Exits): + - Stop rejecting all IPv6 traffic on Exits whose exit policy rejects + any IPv6 addresses. Instead, only reject a port over IPv6 if the + exit policy rejects that port on more than an IPv6 /16 of + addresses. This bug was made worse by 17027 in 0.2.8.1-alpha, + which rejected a relay's own IPv6 address by default. Fixes bug + 21357; bugfix on commit 004f3f4e53 in 0.2.4.7-alpha. + + o Major bugfixes (parsing): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + - When parsing a malformed content-length field from an HTTP + message, do not read off the end of the buffer. This bug was a + potential remote denial-of-service attack against Tor clients and + relays. A workaround was released in October 2016, to prevent this + bug from crashing Tor. This is a fix for the underlying issue, + which should no longer matter (if you applied the earlier patch). + Fixes bug 20894; bugfix on 0.2.0.16-alpha. Bug found by fuzzing + using AFL (http://lcamtuf.coredump.cx/afl/). + + o Major bugfixes (scheduler): + - Actually compare circuit policies in ewma_cmp_cmux(). This bug + caused the channel scheduler to behave more or less randomly, + rather than preferring channels with higher-priority circuits. + Fixes bug 20459; bugfix on 0.2.6.2-alpha. + + o Major bugfixes (security, also in 0.2.9.9): + - Downgrade the "-ftrapv" option from "always on" to "only on when + --enable-expensive-hardening is provided." This hardening option, + like others, can turn survivable bugs into crashes--and having it + on by default made a (relatively harmless) integer overflow bug + into a denial-of-service bug. Fixes bug 21278 (TROVE-2017-001); + bugfix on 0.2.9.1-alpha. + + o Minor feature (client): + - Enable IPv6 traffic on the SocksPort by default. To disable this, + a user will have to specify "NoIPv6Traffic". Closes ticket 21269. + + o Minor feature (fallback scripts): + - Add a check_existing mode to updateFallbackDirs.py, which checks + if fallbacks in the hard-coded list are working. Closes ticket + 20174. Patch by haxxpop. + + o Minor feature (protocol versioning): + - Add new protocol version for proposal 224. HSIntro now advertises + version "3-4" and HSDir version "1-2". Fixes ticket 20656. + + o Minor features (ciphersuite selection): + - Allow relays to accept a wider range of ciphersuites, including + chacha20-poly1305 and AES-CCM. Closes the other part of 15426. + - Clients now advertise a list of ciphersuites closer to the ones + preferred by Firefox. Closes part of ticket 15426. + + o Minor features (controller): + - Add "GETINFO sr/current" and "GETINFO sr/previous" keys, to expose + shared-random values to the controller. Closes ticket 19925. + - When HSFETCH arguments cannot be parsed, say "Invalid argument" + rather than "unrecognized." Closes ticket 20389; patch from + Ivan Markin. + + o Minor features (controller, configuration): + - Each of the *Port options, such as SocksPort, ORPort, ControlPort, + and so on, now comes with a __*Port variant that will not be saved + to the torrc file by the controller's SAVECONF command. This + change allows TorBrowser to set up a single-use domain socket for + each time it launches Tor. Closes ticket 20956. + - The GETCONF command can now query options that may only be + meaningful in context-sensitive lists. This allows the controller + to query the mixed SocksPort/__SocksPort style options introduced + in feature 20956. Implements ticket 21300. + + o Minor features (diagnostic, directory client): + - Warn when we find an unexpected inconsistency in directory + download status objects. Prevents some negative consequences of + bug 20593. + + o Minor features (directory authorities): + - Directory authorities now reject descriptors that claim to be + malformed versions of Tor. Helps prevent exploitation of + bug 21278. + - Reject version numbers with components that exceed INT32_MAX. + Otherwise 32-bit and 64-bit platforms would behave inconsistently. + Fixes bug 21450; bugfix on 0.0.8pre1. + + o Minor features (directory authority): + - Add a new authority-only AuthDirTestEd25519LinkKeys option (on by + default) to control whether authorities should try to probe relays + by their Ed25519 link keys. This option will go away in a few + releases--unless we encounter major trouble in our ed25519 link + protocol rollout, in which case it will serve as a safety option. + + o Minor features (directory cache): + - Relays and bridges will now refuse to serve the consensus they + have if they know it is too old for a client to use. Closes + ticket 20511. + + o Minor features (ed25519 link handshake): + - Advertise support for the ed25519 link handshake using the + subprotocol-versions mechanism, so that clients can tell which + relays can identity themselves by Ed25519 ID. Closes ticket 20552. + + o Minor features (entry guards): + - Add UseEntryGuards to TEST_OPTIONS_DEFAULT_VALUES in order to not + break regression tests. + - Require UseEntryGuards when UseBridges is set, in order to make + sure bridges aren't bypassed. Resolves ticket 20502. + + o Minor features (fallback directories): + - Allow 3 fallback relays per operator, which is safe now that we + are choosing 200 fallback relays. Closes ticket 20912. + - Annotate updateFallbackDirs.py with the bandwidth and consensus + weight for each candidate fallback. Closes ticket 20878. + - Display the relay fingerprint when downloading consensuses from + fallbacks. Closes ticket 20908. + - Exclude relays affected by bug 20499 from the fallback list. + Exclude relays from the fallback list if they are running versions + known to be affected by bug 20499, or if in our tests they deliver + a stale consensus (i.e. one that expired more than 24 hours ago). + Closes ticket 20539. + - Make it easier to change the output sort order of fallbacks. + Closes ticket 20822. + - Reduce the minimum fallback bandwidth to 1 MByte/s. Part of + ticket 18828. + - Require fallback directories to have the same address and port for + 7 days (now that we have enough relays with this stability). + Relays whose OnionOO stability timer is reset on restart by bug + 18050 should upgrade to Tor 0.2.8.7 or later, which has a fix for + this issue. Closes ticket 20880; maintains short-term fix + in 0.2.8.2-alpha. + - Require fallbacks to have flags for 90% of the time (weighted + decaying average), rather than 95%. This allows at least 73% of + clients to bootstrap in the first 5 seconds without contacting an + authority. Part of ticket 18828. + - Select 200 fallback directories for each release. Closes + ticket 20881. + + o Minor features (fingerprinting resistence, authentication): + - Extend the length of RSA keys used for TLS link authentication to + 2048 bits. (These weren't used for forward secrecy; for forward + secrecy, we used P256.) Closes ticket 13752. + + o Minor features (geoip): + - Update geoip and geoip6 to the April 4 2017 Maxmind GeoLite2 + Country database. + + o Minor features (geoip, also in 0.2.9.9): + - Update geoip and geoip6 to the January 4 2017 Maxmind GeoLite2 + Country database. + + o Minor features (infrastructure): + - Implement smartlist_add_strdup() function. Replaces the use of + smartlist_add(sl, tor_strdup(str)). Closes ticket 20048. + + o Minor features (linting): + - Enhance the changes file linter to warn on Tor versions that are + prefixed with "tor-". Closes ticket 21096. + + o Minor features (logging): + - In several places, describe unset ed25519 keys as "<unset>", + rather than the scary "AAAAAAAA...AAA". Closes ticket 21037. + + o Minor features (portability, compilation): + - Autoconf now checks to determine if OpenSSL structures are opaque, + instead of explicitly checking for OpenSSL version numbers. Part + of ticket 21359. + - Support building with recent LibreSSL code that uses opaque + structures. Closes ticket 21359. + + o Minor features (relay): + - We now allow separation of exit and relay traffic to different + source IP addresses, using the OutboundBindAddressExit and + OutboundBindAddressOR options respectively. Closes ticket 17975. + Written by Michael Sonntag. + + o Minor features (reliability, crash): + - Try better to detect problems in buffers where they might grow (or + think they have grown) over 2 GB in size. Diagnostic for + bug 21369. + + o Minor features (testing): + - During 'make test-network-all', if tor logs any warnings, ask + chutney to output them. Requires a recent version of chutney with + the 21572 patch. Implements 21570. + + o Minor bugfix (control protocol): + - The reply to a "GETINFO config/names" request via the control + protocol now spells the type "Dependent" correctly. This is a + breaking change in the control protocol. (The field seems to be + ignored by the most common known controllers.) Fixes bug 18146; + bugfix on 0.1.1.4-alpha. + - The GETINFO extra-info/digest/<digest> command was broken because + of a wrong base16 decode return value check, introduced when + refactoring that API. Fixes bug 22034; bugfix on 0.2.9.1-alpha. + + o Minor bugfix (logging): + - Don't recommend the use of Tor2web in non-anonymous mode. + Recommending Tor2web is a bad idea because the client loses all + anonymity. Tor2web should only be used in specific cases by users + who *know* and understand the issues. Fixes bug 21294; bugfix + on 0.2.9.3-alpha. + + o Minor bugfixes (bug resilience): + - Fix an unreachable size_t overflow in base64_decode(). Fixes bug + 19222; bugfix on 0.2.0.9-alpha. Found by Guido Vranken; fixed by + Hans Jerry Illikainen. + + o Minor bugfixes (build): + - Replace obsolete Autoconf macros with their modern equivalent and + prevent similar issues in the future. Fixes bug 20990; bugfix + on 0.1.0.1-rc. + + o Minor bugfixes (certificate expiration time): + - Avoid using link certificates that don't become valid till some + time in the future. Fixes bug 21420; bugfix on 0.2.4.11-alpha + + o Minor bugfixes (client): + - Always recover from failures in extend_info_from_node(), in an + attempt to prevent any recurrence of bug 21242. Fixes bug 21372; + bugfix on 0.2.3.1-alpha. + - When clients that use bridges start up with a cached consensus on + disk, they were ignoring it and downloading a new one. Now they + use the cached one. Fixes bug 20269; bugfix on 0.2.3.12-alpha. + + o Minor bugfixes (code correctness): + - Repair a couple of (unreachable or harmless) cases of the risky + comparison-by-subtraction pattern that caused bug 21278. + + o Minor bugfixes (config): + - Don't assert on startup when trying to get the options list and + LearnCircuitBuildTimeout is set to 0: we are currently parsing the + options so of course they aren't ready yet. Fixes bug 21062; + bugfix on 0.2.9.3-alpha. + + o Minor bugfixes (configuration): + - Accept non-space whitespace characters after the severity level in + the `Log` option. Fixes bug 19965; bugfix on 0.2.1.1-alpha. + - Support "TByte" and "TBytes" units in options given in bytes. + "TB", "terabyte(s)", "TBit(s)" and "terabit(s)" were already + supported. Fixes bug 20622; bugfix on 0.2.0.14-alpha. + + o Minor bugfixes (configure, autoconf): + - Rename the configure option --enable-expensive-hardening to + --enable-fragile-hardening. Expensive hardening makes the tor + daemon abort when some kinds of issues are detected. Thus, it + makes tor more at risk of remote crashes but safer against RCE or + heartbleed bug category. We now try to explain this issue in a + message from the configure script. Fixes bug 21290; bugfix + on 0.2.5.4-alpha. + + o Minor bugfixes (consensus weight): + - Add new consensus method that initializes bw weights to 1 instead + of 0. This prevents a zero weight from making it all the way to + the end (happens in small testing networks) and causing an error. + Fixes bug 14881; bugfix on 0.2.2.17-alpha. + + o Minor bugfixes (crash prevention): + - Fix an (currently untriggerable, but potentially dangerous) crash + bug when base32-encoding inputs whose sizes are not a multiple of + 5. Fixes bug 21894; bugfix on 0.2.9.1-alpha. + + o Minor bugfixes (dead code): + - Remove a redundant check for PidFile changes at runtime in + options_transition_allowed(): this check is already performed + regardless of whether the sandbox is active. Fixes bug 21123; + bugfix on 0.2.5.4-alpha. + + o Minor bugfixes (descriptors): + - Correctly recognise downloaded full descriptors as valid, even + when using microdescriptors as circuits. This affects clients with + FetchUselessDescriptors set, and may affect directory authorities. + Fixes bug 20839; bugfix on 0.2.3.2-alpha. + + o Minor bugfixes (directory mirrors): + - Allow relays to use directory mirrors without a DirPort: these + relays need to be contacted over their ORPorts using a begindir + connection. Fixes one case of bug 20711; bugfix on 0.2.8.2-alpha. + - Clarify the message logged when a remote relay is unexpectedly + missing an ORPort or DirPort: users were confusing this with a + local port. Fixes another case of bug 20711; bugfix + on 0.2.8.2-alpha. + + o Minor bugfixes (directory system): + - Bridges and relays now use microdescriptors (like clients do) + rather than old-style router descriptors. Now bridges will blend + in with clients in terms of the circuits they build. Fixes bug + 6769; bugfix on 0.2.3.2-alpha. + - Download all consensus flavors, descriptors, and authority + certificates when FetchUselessDescriptors is set, regardless of + whether tor is a directory cache or not. Fixes bug 20667; bugfix + on all recent tor versions. + + o Minor bugfixes (documentation): + - Update the tor manual page to document every option that can not + be changed while tor is running. Fixes bug 21122. + + o Minor bugfixes (ed25519 certificates): + - Correctly interpret ed25519 certificates that would expire some + time after 19 Jan 2038. Fixes bug 20027; bugfix on 0.2.7.2-alpha. + + o Minor bugfixes (fallback directories): + - Avoid checking fallback candidates' DirPorts if they are down in + OnionOO. When a relay operator has multiple relays, this + prioritizes relays that are up over relays that are down. Fixes + bug 20926; bugfix on 0.2.8.3-alpha. + - Stop failing when OUTPUT_COMMENTS is True in updateFallbackDirs.py. + Fixes bug 20877; bugfix on 0.2.8.3-alpha. + - Stop failing when a relay has no uptime data in + updateFallbackDirs.py. Fixes bug 20945; bugfix on 0.2.8.1-alpha. + + o Minor bugfixes (hidden service): + - Clean up the code for expiring intro points with no associated + circuits. It was causing, rarely, a service with some expiring + introduction points to not open enough additional introduction + points. Fixes part of bug 21302; bugfix on 0.2.7.2-alpha. + - Resolve two possible underflows which could lead to creating and + closing a lot of introduction point circuits in a non-stop loop. + Fixes bug 21302; bugfix on 0.2.7.2-alpha. + - Stop setting the torrc option HiddenServiceStatistics to "0" just + because we're not a bridge or relay. Instead, we preserve whatever + value the user set (or didn't set). Fixes bug 21150; bugfix + on 0.2.6.2-alpha. + + o Minor bugfixes (hidden services): + - Make hidden services check for failed intro point connections, + even when they have exceeded their intro point creation limit. + Fixes bug 21596; bugfix on 0.2.7.2-alpha. Reported by Alec Muffett. + - Make hidden services with 8 to 10 introduction points check for + failed circuits immediately after startup. Previously, they would + wait for 5 minutes before performing their first checks. Fixes bug + 21594; bugfix on 0.2.3.9-alpha. Reported by Alec Muffett. + - Stop ignoring misconfigured hidden services. Instead, refuse to + start tor until the misconfigurations have been corrected. Fixes + bug 20559; bugfix on multiple commits in 0.2.7.1-alpha + and earlier. + + o Minor bugfixes (IPv6): + - Make IPv6-using clients try harder to find an IPv6 directory + server. Fixes bug 20999; bugfix on 0.2.8.2-alpha. + - When IPv6 addresses have not been downloaded yet (microdesc + consensus documents don't list relay IPv6 addresses), use hard- + coded addresses for authorities, fallbacks, and configured + bridges. Now IPv6-only clients can use microdescriptors. Fixes bug + 20996; bugfix on b167e82 from 19608 in 0.2.8.5-alpha. + + o Minor bugfixes (memory leak at exit): + - Fix a small harmless memory leak at exit of the previously unused + RSA->Ed identity cross-certificate. Fixes bug 17779; bugfix + on 0.2.7.2-alpha. + + o Minor bugfixes (onion services): + - Allow the number of introduction points to be as low as 0, rather + than as low as 3. Fixes bug 21033; bugfix on 0.2.7.2-alpha. + + o Minor bugfixes (portability): + - Use "OpenBSD" compiler macro instead of "OPENBSD" or "__OpenBSD__". + It is supported by OpenBSD itself, and also by most OpenBSD + variants (such as Bitrig). Fixes bug 20980; bugfix + on 0.1.2.1-alpha. + + o Minor bugfixes (portability, also in 0.2.9.9): + - Avoid crashing when Tor is built using headers that contain + CLOCK_MONOTONIC_COARSE, but then tries to run on an older kernel + without CLOCK_MONOTONIC_COARSE. Fixes bug 21035; bugfix + on 0.2.9.1-alpha. + - Fix Libevent detection on platforms without Libevent 1 headers + installed. Fixes bug 21051; bugfix on 0.2.9.1-alpha. + + o Minor bugfixes (relay): + - Avoid a double-marked-circuit warning that could happen when we + receive DESTROY cells under heavy load. Fixes bug 20059; bugfix + on 0.1.0.1-rc. + - Honor DataDirectoryGroupReadable when tor is a relay. Previously, + initializing the keys would reset the DataDirectory to 0700 + instead of 0750 even if DataDirectoryGroupReadable was set to 1. + Fixes bug 19953; bugfix on 0.0.2pre16. Patch by "redfish". + + o Minor bugfixes (testing): + - Fix Raspbian build issues related to missing socket errno in + test_util.c. Fixes bug 21116; bugfix on 0.2.8.2. Patch by "hein". + - Remove undefined behavior from the backtrace generator by removing + its signal handler. Fixes bug 21026; bugfix on 0.2.5.2-alpha. + - Use bash in src/test/test-network.sh. This ensures we reliably + call chutney's newer tools/test-network.sh when available. Fixes + bug 21562; bugfix on 0.2.9.1-alpha. + + o Minor bugfixes (tor-resolve): + - The tor-resolve command line tool now rejects hostnames over 255 + characters in length. Previously, it would silently truncate them, + which could lead to bugs. Fixes bug 21280; bugfix on 0.0.9pre5. + Patch by "junglefowl". + + o Minor bugfixes (unit tests): + - Allow the unit tests to pass even when DNS lookups of bogus + addresses do not fail as expected. Fixes bug 20862 and 20863; + bugfix on unit tests introduced in 0.2.8.1-alpha + through 0.2.9.4-alpha. + + o Minor bugfixes (util): + - When finishing writing a file to disk, if we were about to replace + the file with the temporary file created before and we fail to + replace it, remove the temporary file so it doesn't stay on disk. + Fixes bug 20646; bugfix on 0.2.0.7-alpha. Patch by fk. + + o Minor bugfixes (Windows services): + - Be sure to initialize the monotonic time subsystem before using + it, even when running as an NT service. Fixes bug 21356; bugfix + on 0.2.9.1-alpha. + + o Minor bugfixes (Windows): + - Check for getpagesize before using it to mmap files. This fixes + compilation in some MinGW environments. Fixes bug 20530; bugfix on + 0.1.2.1-alpha. Reported by "ice". + + o Code simplification and refactoring: + - Abolish all global guard context in entrynodes.c; replace with new + guard_selection_t structure as preparation for proposal 271. + Closes ticket 19858. + - Extract magic numbers in circuituse.c into defined variables. + - Introduce rend_service_is_ephemeral() that tells if given onion + service is ephemeral. Replace unclear NULL-checkings for service + directory with this function. Closes ticket 20526. + - Refactor circuit_is_available_for_use to remove unnecessary check. + - Refactor circuit_predict_and_launch_new for readability and + testability. Closes ticket 18873. + - Refactor code to manipulate global_origin_circuit_list into + separate functions. Closes ticket 20921. + - Refactor large if statement in purpose_needs_anonymity to use + switch statement instead. Closes part of ticket 20077. + - Refactor the hashing API to return negative values for errors, as + is done as throughout the codebase. Closes ticket 20717. + - Remove data structures that were used to index or_connection + objects by their RSA identity digests. These structures are fully + redundant with the similar structures used in the + channel abstraction. + - Remove duplicate code in the channel_write_*cell() functions. + Closes ticket 13827; patch from Pingl. + - Remove redundant behavior of is_sensitive_dir_purpose, refactor to + use only purpose_needs_anonymity. Closes part of ticket 20077. + - The code to generate and parse EXTEND and EXTEND2 cells has been + replaced with code automatically generated by the + "trunnel" utility. + + o Documentation (formatting): + - Clean up formatting of tor.1 man page and HTML doc, where <pre> + blocks were incorrectly appearing. Closes ticket 20885. + + o Documentation (man page): + - Clarify many options in tor.1 and add some min/max values for + HiddenService options. Closes ticket 21058. + + o Documentation: + - Change '1' to 'weight_scale' in consensus bw weights calculation + comments, as that is reality. Closes ticket 20273. Patch + from pastly. + - Clarify that when ClientRejectInternalAddresses is enabled (which + is the default), multicast DNS hostnames for machines on the local + network (of the form *.local) are also rejected. Closes + ticket 17070. + - Correct the value for AuthDirGuardBWGuarantee in the manpage, from + 250 KBytes to 2 MBytes. Fixes bug 20435; bugfix on 0.2.5.6-alpha. + - Include the "TBits" unit in Tor's man page. Fixes part of bug + 20622; bugfix on 0.2.5.1-alpha. + - Small fixes to the fuzzing documentation. Closes ticket 21472. + - Stop the man page from incorrectly stating that HiddenServiceDir + must already exist. Fixes 20486. + - Update the description of the directory server options in the + manual page, to clarify that a relay no longer needs to set + DirPort in order to be a directory cache. Closes ticket 21720. + + o Removed features: + - The AuthDirMaxServersPerAuthAddr option no longer exists: The same + limit for relays running on a single IP applies to authority IP + addresses as well as to non-authority IP addresses. Closes + ticket 20960. + - The UseDirectoryGuards torrc option no longer exists: all users + that use entry guards will also use directory guards. Related to + proposal 271; implements part of ticket 20831. + + o Testing: + - Add tests for networkstatus_compute_bw_weights_v10. + - Add unit tests circuit_predict_and_launch_new. + - Extract dummy_origin_circuit_new so it can be used by other + test functions. + - New unit tests for tor_htonll(). Closes ticket 19563. Patch + from "overcaffeinated". + - Perform the coding style checks when running the tests and fail + when coding style violations are found. Closes ticket 5500. + + +Changes in version 0.2.8.13 - 2017-03-03 + Tor 0.2.8.13 backports a security fix from later Tor + releases. Anybody running Tor 0.2.8.12 or earlier should upgrade to this + this release, if for some reason they cannot upgrade to a later + release series, and if they build Tor with the --enable-expensive-hardening + option. + + Note that support for Tor 0.2.8.x is ending next year: we will not issue + any fixes for the Tor 0.2.8.x series after 1 Jan 2018. If you need + a Tor release series with longer-term support, we recommend Tor 0.2.9.x. + + o Major bugfixes (parsing, backported from 0.3.0.4-rc): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + + o Minor features (geoip): + - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 + Country database. + + +Changes in version 0.2.7.7 - 2017-03-03 + Tor 0.2.7.7 backports a number of security fixes from later Tor + releases. Anybody running Tor 0.2.7.6 or earlier should upgrade to + this release, if for some reason they cannot upgrade to a later + release series. + + Note that support for Tor 0.2.7.x is ending this year: we will not issue + any fixes for the Tor 0.2.7.x series after 1 August 2017. If you need + a Tor release series with longer-term support, we recommend Tor 0.2.9.x. + + o Directory authority changes (backport from 0.2.8.5-rc): + - Urras is no longer a directory authority. Closes ticket 19271. + + o Directory authority changes (backport from 0.2.9.2-alpha): + - The "Tonga" bridge authority has been retired; the new bridge + authority is "Bifroest". Closes tickets 19728 and 19690. + + o Directory authority key updates (backport from 0.2.8.1-alpha): + - Update the V3 identity key for the dannenberg directory authority: + it was changed on 18 November 2015. Closes task 17906. Patch + by "teor". + + o Major bugfixes (parsing, security, backport from 0.2.9.8): + - Fix a bug in parsing that could cause clients to read a single + byte past the end of an allocated region. This bug could be used + to cause hardened clients (built with --enable-expensive-hardening) + to crash if they tried to visit a hostile hidden service. Non- + hardened clients are only affected depending on the details of + their platform's memory allocator. Fixes bug 21018; bugfix on + 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- + 2016-12-002 and as CVE-2016-1254. + + o Major bugfixes (security, client, DNS proxy, backport from 0.2.8.3-alpha): + - Stop a crash that could occur when a client running with DNSPort + received a query with multiple address types, and the first + address type was not supported. Found and fixed by Scott Dial. + Fixes bug 18710; bugfix on 0.2.5.4-alpha. + - Prevent a class of security bugs caused by treating the contents + of a buffer chunk as if they were a NUL-terminated string. At + least one such bug seems to be present in all currently used + versions of Tor, and would allow an attacker to remotely crash + most Tor instances, especially those compiled with extra compiler + hardening. With this defense in place, such bugs can't crash Tor, + though we should still fix them as they occur. Closes ticket + 20384 (TROVE-2016-10-001). + + o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): + - Avoid a difficult-to-trigger heap corruption attack when extending + a smartlist to contain over 16GB of pointers. Fixes bug 18162; + bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. + Reported by Guido Vranken. + + o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): + - Avoid crashing when running as a DNS proxy. Fixes bug 16248; + bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". + + o Major bugfixes (key management, backport from 0.2.8.3-alpha): + - If OpenSSL fails to generate an RSA key, do not retain a dangling + pointer to the previous (uninitialized) key value. The impact here + should be limited to a difficult-to-trigger crash, if OpenSSL is + running an engine that makes key generation failures possible, or + if OpenSSL runs out of memory. Fixes bug 19152; bugfix on + 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and + Baishakhi Ray. + + o Major bugfixes (parsing, backported from 0.3.0.4-rc): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + + o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): + - Make memwipe() do nothing when passed a NULL pointer or buffer of + zero size. Check size argument to memwipe() for underflow. Fixes + bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", + patch by "teor". + + o Minor features (bug-resistance, backport from 0.2.8.2-alpha): + - Make Tor survive errors involving connections without a + corresponding event object. Previously we'd fail with an + assertion; now we produce a log message. Related to bug 16248. + + o Minor features (geoip): + - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 + Country database. + + +Changes in version 0.2.6.11 - 2017-03-03 + Tor 0.2.6.11 backports a number of security fixes from later Tor + releases. Anybody running Tor 0.2.6.10 or earlier should upgrade to + this release, if for some reason they cannot upgrade to a later + release series. + + Note that support for Tor 0.2.6.x is ending this year: we will not issue + any fixes for the Tor 0.2.6.x series after 1 August 2017. If you need + a Tor release series with longer-term support, we recommend Tor 0.2.9.x. + + o Directory authority changes (backport from 0.2.8.5-rc): + - Urras is no longer a directory authority. Closes ticket 19271. + + o Directory authority changes (backport from 0.2.9.2-alpha): + - The "Tonga" bridge authority has been retired; the new bridge + authority is "Bifroest". Closes tickets 19728 and 19690. + + o Directory authority key updates (backport from 0.2.8.1-alpha): + - Update the V3 identity key for the dannenberg directory authority: + it was changed on 18 November 2015. Closes task 17906. Patch + by "teor". + + o Major features (security fixes, backport from 0.2.9.4-alpha): + - Prevent a class of security bugs caused by treating the contents + of a buffer chunk as if they were a NUL-terminated string. At + least one such bug seems to be present in all currently used + versions of Tor, and would allow an attacker to remotely crash + most Tor instances, especially those compiled with extra compiler + hardening. With this defense in place, such bugs can't crash Tor, + though we should still fix them as they occur. Closes ticket + 20384 (TROVE-2016-10-001). + + o Major bugfixes (parsing, security, backport from 0.2.9.8): + - Fix a bug in parsing that could cause clients to read a single + byte past the end of an allocated region. This bug could be used + to cause hardened clients (built with --enable-expensive-hardening) + to crash if they tried to visit a hostile hidden service. Non- + hardened clients are only affected depending on the details of + their platform's memory allocator. Fixes bug 21018; bugfix on + 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- + 2016-12-002 and as CVE-2016-1254. + + o Major bugfixes (security, client, DNS proxy, backport from 0.2.8.3-alpha): + - Stop a crash that could occur when a client running with DNSPort + received a query with multiple address types, and the first + address type was not supported. Found and fixed by Scott Dial. + Fixes bug 18710; bugfix on 0.2.5.4-alpha. + + o Major bugfixes (security, correctness, backport from 0.2.7.4-rc): + - Fix an error that could cause us to read 4 bytes before the + beginning of an openssl string. This bug could be used to cause + Tor to crash on systems with unusual malloc implementations, or + systems with unusual hardening installed. Fixes bug 17404; bugfix + on 0.2.3.6-alpha. + + o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): + - Avoid a difficult-to-trigger heap corruption attack when extending + a smartlist to contain over 16GB of pointers. Fixes bug 18162; + bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. + Reported by Guido Vranken. + + o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): + - Avoid crashing when running as a DNS proxy. Fixes bug 16248; + bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". + + o Major bugfixes (guard selection, backport from 0.2.7.6): + - Actually look at the Guard flag when selecting a new directory + guard. When we implemented the directory guard design, we + accidentally started treating all relays as if they have the Guard + flag during guard selection, leading to weaker anonymity and worse + performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered + by Mohsen Imani. + + o Major bugfixes (key management, backport from 0.2.8.3-alpha): + - If OpenSSL fails to generate an RSA key, do not retain a dangling + pointer to the previous (uninitialized) key value. The impact here + should be limited to a difficult-to-trigger crash, if OpenSSL is + running an engine that makes key generation failures possible, or + if OpenSSL runs out of memory. Fixes bug 19152; bugfix on + 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and + Baishakhi Ray. + + o Major bugfixes (parsing, backported from 0.3.0.4-rc): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + + o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): + - Make memwipe() do nothing when passed a NULL pointer or buffer of + zero size. Check size argument to memwipe() for underflow. Fixes + bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", + patch by "teor". + + o Minor features (bug-resistance, backport from 0.2.8.2-alpha): + - Make Tor survive errors involving connections without a + corresponding event object. Previously we'd fail with an + assertion; now we produce a log message. Related to bug 16248. + + o Minor features (geoip): + - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (compilation, backport from 0.2.7.6): + - Fix a compilation warning with Clang 3.6: Do not check the + presence of an address which can never be NULL. Fixes bug 17781. + + +Changes in version 0.2.5.13 - 2017-03-03 + Tor 0.2.5.13 backports a number of security fixes from later Tor + releases. Anybody running Tor 0.2.5.13 or earlier should upgrade to + this release, if for some reason they cannot upgrade to a later + release series. + + Note that support for Tor 0.2.5.x is ending next year: we will not issue + any fixes for the Tor 0.2.5.x series after 1 May 2018. If you need + a Tor release series with longer-term support, we recommend Tor 0.2.9.x. + + o Directory authority changes (backport from 0.2.8.5-rc): + - Urras is no longer a directory authority. Closes ticket 19271. + + o Directory authority changes (backport from 0.2.9.2-alpha): + - The "Tonga" bridge authority has been retired; the new bridge + authority is "Bifroest". Closes tickets 19728 and 19690. + + o Directory authority key updates (backport from 0.2.8.1-alpha): + - Update the V3 identity key for the dannenberg directory authority: + it was changed on 18 November 2015. Closes task 17906. Patch + by "teor". + + o Major features (security fixes, backport from 0.2.9.4-alpha): + - Prevent a class of security bugs caused by treating the contents + of a buffer chunk as if they were a NUL-terminated string. At + least one such bug seems to be present in all currently used + versions of Tor, and would allow an attacker to remotely crash + most Tor instances, especially those compiled with extra compiler + hardening. With this defense in place, such bugs can't crash Tor, + though we should still fix them as they occur. Closes ticket + 20384 (TROVE-2016-10-001). + + o Major bugfixes (parsing, security, backport from 0.2.9.8): + - Fix a bug in parsing that could cause clients to read a single + byte past the end of an allocated region. This bug could be used + to cause hardened clients (built with --enable-expensive-hardening) + to crash if they tried to visit a hostile hidden service. Non- + hardened clients are only affected depending on the details of + their platform's memory allocator. Fixes bug 21018; bugfix on + 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- + 2016-12-002 and as CVE-2016-1254. + + o Major bugfixes (security, client, DNS proxy, backport from 0.2.8.3-alpha): + - Stop a crash that could occur when a client running with DNSPort + received a query with multiple address types, and the first + address type was not supported. Found and fixed by Scott Dial. + Fixes bug 18710; bugfix on 0.2.5.4-alpha. + + o Major bugfixes (security, correctness, backport from 0.2.7.4-rc): + - Fix an error that could cause us to read 4 bytes before the + beginning of an openssl string. This bug could be used to cause + Tor to crash on systems with unusual malloc implementations, or + systems with unusual hardening installed. Fixes bug 17404; bugfix + on 0.2.3.6-alpha. + + o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): + - Avoid a difficult-to-trigger heap corruption attack when extending + a smartlist to contain over 16GB of pointers. Fixes bug 18162; + bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. + Reported by Guido Vranken. + + o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): + - Avoid crashing when running as a DNS proxy. Fixes bug 16248; + bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". + + o Major bugfixes (guard selection, backport from 0.2.7.6): + - Actually look at the Guard flag when selecting a new directory + guard. When we implemented the directory guard design, we + accidentally started treating all relays as if they have the Guard + flag during guard selection, leading to weaker anonymity and worse + performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered + by Mohsen Imani. + + o Major bugfixes (key management, backport from 0.2.8.3-alpha): + - If OpenSSL fails to generate an RSA key, do not retain a dangling + pointer to the previous (uninitialized) key value. The impact here + should be limited to a difficult-to-trigger crash, if OpenSSL is + running an engine that makes key generation failures possible, or + if OpenSSL runs out of memory. Fixes bug 19152; bugfix on + 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and + Baishakhi Ray. + + o Major bugfixes (parsing, backported from 0.3.0.4-rc): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + + o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): + - Make memwipe() do nothing when passed a NULL pointer or buffer of + zero size. Check size argument to memwipe() for underflow. Fixes + bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", + patch by "teor". + + o Minor features (bug-resistance, backport from 0.2.8.2-alpha): + - Make Tor survive errors involving connections without a + corresponding event object. Previously we'd fail with an + assertion; now we produce a log message. Related to bug 16248. + + o Minor features (geoip): + - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (compilation, backport from 0.2.7.6): + - Fix a compilation warning with Clang 3.6: Do not check the + presence of an address which can never be NULL. Fixes bug 17781. + + o Minor bugfixes (crypto error-handling, backport from 0.2.7.2-alpha): + - Check for failures from crypto_early_init, and refuse to continue. + A previous typo meant that we could keep going with an + uninitialized crypto library, and would have OpenSSL initialize + its own PRNG. Fixes bug 16360; bugfix on 0.2.5.2-alpha, introduced + when implementing ticket 4900. Patch by "teor". + + 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. + + +Changes in version 0.2.4.28 - 2017-03-03 + Tor 0.2.4.28 backports a number of security fixes from later Tor + releases. Anybody running Tor 0.2.4.27 or earlier should upgrade to + this release, if for some reason they cannot upgrade to a later + release series. + + Note that support for Tor 0.2.4.x is ending soon: we will not issue + any fixes for the Tor 0.2.4.x series after 1 August 2017. If you need + a Tor release series with long-term support, we recommend Tor 0.2.9.x. + + o Directory authority changes (backport from 0.2.8.5-rc): + - Urras is no longer a directory authority. Closes ticket 19271. + + o Directory authority changes (backport from 0.2.9.2-alpha): + - The "Tonga" bridge authority has been retired; the new bridge + authority is "Bifroest". Closes tickets 19728 and 19690. + + o Directory authority key updates (backport from 0.2.8.1-alpha): + - Update the V3 identity key for the dannenberg directory authority: + it was changed on 18 November 2015. Closes task 17906. Patch + by "teor". + + o Major features (security fixes, backport from 0.2.9.4-alpha): + - Prevent a class of security bugs caused by treating the contents + of a buffer chunk as if they were a NUL-terminated string. At + least one such bug seems to be present in all currently used + versions of Tor, and would allow an attacker to remotely crash + most Tor instances, especially those compiled with extra compiler + hardening. With this defense in place, such bugs can't crash Tor, + though we should still fix them as they occur. Closes ticket + 20384 (TROVE-2016-10-001). + + o Major bugfixes (parsing, security, backport from 0.2.9.8): + - Fix a bug in parsing that could cause clients to read a single + byte past the end of an allocated region. This bug could be used + to cause hardened clients (built with --enable-expensive-hardening) + to crash if they tried to visit a hostile hidden service. Non- + hardened clients are only affected depending on the details of + their platform's memory allocator. Fixes bug 21018; bugfix on + 0.2.0.8-alpha. Found by using libFuzzer. Also tracked as TROVE- + 2016-12-002 and as CVE-2016-1254. + + o Major bugfixes (security, correctness, backport from 0.2.7.4-rc): + - Fix an error that could cause us to read 4 bytes before the + beginning of an openssl string. This bug could be used to cause + Tor to crash on systems with unusual malloc implementations, or + systems with unusual hardening installed. Fixes bug 17404; bugfix + on 0.2.3.6-alpha. + + o Major bugfixes (security, pointers, backport from 0.2.8.2-alpha): + - Avoid a difficult-to-trigger heap corruption attack when extending + a smartlist to contain over 16GB of pointers. Fixes bug 18162; + bugfix on 0.1.1.11-alpha, which fixed a related bug incompletely. + Reported by Guido Vranken. + + o Major bugfixes (dns proxy mode, crash, backport from 0.2.8.2-alpha): + - Avoid crashing when running as a DNS proxy. Fixes bug 16248; + bugfix on 0.2.0.1-alpha. Patch from "cypherpunks". + + o Major bugfixes (guard selection, backport from 0.2.7.6): + - Actually look at the Guard flag when selecting a new directory + guard. When we implemented the directory guard design, we + accidentally started treating all relays as if they have the Guard + flag during guard selection, leading to weaker anonymity and worse + performance. Fixes bug 17772; bugfix on 0.2.4.8-alpha. Discovered + by Mohsen Imani. + + o Major bugfixes (key management, backport from 0.2.8.3-alpha): + - If OpenSSL fails to generate an RSA key, do not retain a dangling + pointer to the previous (uninitialized) key value. The impact here + should be limited to a difficult-to-trigger crash, if OpenSSL is + running an engine that makes key generation failures possible, or + if OpenSSL runs out of memory. Fixes bug 19152; bugfix on + 0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and + Baishakhi Ray. + + o Major bugfixes (parsing, backported from 0.3.0.4-rc): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + + o Minor features (security, memory erasure, backport from 0.2.8.1-alpha): + - Make memwipe() do nothing when passed a NULL pointer or buffer of + zero size. Check size argument to memwipe() for underflow. Fixes + bug 18089; bugfix on 0.2.3.25 and 0.2.4.6-alpha. Reported by "gk", + patch by "teor". + + o Minor features (bug-resistance, backport from 0.2.8.2-alpha): + - Make Tor survive errors involving connections without a + corresponding event object. Previously we'd fail with an + assertion; now we produce a log message. Related to bug 16248. + + o Minor features (DoS-resistance, backport from 0.2.7.1-alpha): + - Make it harder for attackers to overload hidden services with + introductions, by blocking multiple introduction requests on the + same circuit. Resolves ticket 15515. + + o Minor features (geoip): + - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 + Country database. + + o Minor bugfixes (compilation, backport from 0.2.7.6): + - Fix a compilation warning with Clang 3.6: Do not check the + presence of an address which can never be NULL. Fixes bug 17781. + + 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. + + +Changes in version 0.2.9.10 - 2017-03-01 + Tor 0.2.9.10 backports a security fix from later Tor release. It also + includes fixes for some major issues affecting directory authorities, + LibreSSL compatibility, and IPv6 correctness. + + The Tor 0.2.9.x release series is now marked as a long-term-support + series. We intend to backport security fixes to 0.2.9.x until at + least January of 2020. + + o Major bugfixes (directory authority, 0.3.0.3-alpha): + - During voting, when marking a relay as a probable sybil, do not + clear its BadExit flag: sybils can still be bad in other ways + too. (We still clear the other flags.) Fixes bug 21108; bugfix + on 0.2.0.13-alpha. + + o Major bugfixes (IPv6 Exits, backport from 0.3.0.3-alpha): + - Stop rejecting all IPv6 traffic on Exits whose exit policy rejects + any IPv6 addresses. Instead, only reject a port over IPv6 if the + exit policy rejects that port on more than an IPv6 /16 of + addresses. This bug was made worse by 17027 in 0.2.8.1-alpha, + which rejected a relay's own IPv6 address by default. Fixes bug + 21357; bugfix on commit 004f3f4e53 in 0.2.4.7-alpha. + + o Major bugfixes (parsing, also in 0.3.0.4-rc): + - Fix an integer underflow bug when comparing malformed Tor + versions. This bug could crash Tor when built with + --enable-expensive-hardening, or on Tor 0.2.9.1-alpha through Tor + 0.2.9.8, which were built with -ftrapv by default. In other cases + it was harmless. Part of TROVE-2017-001. Fixes bug 21278; bugfix + on 0.0.8pre1. Found by OSS-Fuzz. + + o Minor features (directory authorities, also in 0.3.0.4-rc): + - Directory authorities now reject descriptors that claim to be + malformed versions of Tor. Helps prevent exploitation of + bug 21278. + - Reject version numbers with components that exceed INT32_MAX. + Otherwise 32-bit and 64-bit platforms would behave inconsistently. + Fixes bug 21450; bugfix on 0.0.8pre1. + + o Minor features (geoip): + - Update geoip and geoip6 to the February 8 2017 Maxmind GeoLite2 + Country database. + + o Minor features (portability, compilation, backport from 0.3.0.3-alpha): + - Autoconf now checks to determine if OpenSSL structures are opaque, + instead of explicitly checking for OpenSSL version numbers. Part + of ticket 21359. + - Support building with recent LibreSSL code that uses opaque + structures. Closes ticket 21359. + + o Minor bugfixes (code correctness, also in 0.3.0.4-rc): + - Repair a couple of (unreachable or harmless) cases of the risky + comparison-by-subtraction pattern that caused bug 21278. + + o Minor bugfixes (tor-resolve, backport from 0.3.0.3-alpha): + - The tor-resolve command line tool now rejects hostnames over 255 + characters in length. Previously, it would silently truncate them, + which could lead to bugs. Fixes bug 21280; bugfix on 0.0.9pre5. + Patch by "junglefowl". + + Changes in version 0.2.9.9 - 2017-01-23 Tor 0.2.9.9 fixes a denial-of-service bug where an attacker could cause relays and clients to crash, even if they were not built with |