Tor 0.2.4.18 RC

[thylacine]

Tor 0.2.4.18 RC

https://www.torproject.org/dist/win32/tor-0.2.4.18-rc-win32.exe

Changes in version 0.2.4.18-rc - 2013-11-16

Tor 0.2.4.18-rc is the fourth release candidate for the Tor 0.2.4.x

series. It takes a variety of fixes from the 0.2.5.x branch to improve

stability, performance, and better handling of edge cases.

o Major features:

- Re-enable TLS 1.1 and 1.2 when built with OpenSSL 1.0.1e or later.

Resolves ticket 6055. (OpenSSL before 1.0.1 didn't have TLS 1.1 or

1.2, and OpenSSL from 1.0.1 through 1.0.1d had bugs that prevented

renegotiation from working with TLS 1.1 or 1.2, so we had disabled

them to solve bug 6033.)

o Major bugfixes:

- No longer stop reading or writing on cpuworker connections when

our rate limiting buckets go empty. Now we should handle circuit

handshake requests more promptly. Resolves bug 9731.

- If we are unable to save a microdescriptor to the journal, do not

drop it from memory and then reattempt downloading it. Fixes bug

9645; bugfix on 0.2.2.6-alpha.

- Stop trying to bootstrap all our directory information from

only our first guard. Discovered while fixing bug 9946; bugfix

on 0.2.4.8-alpha.

- The new channel code sometimes lost track of in-progress circuits,

causing long-running clients to stop building new circuits. The

fix is to always call circuit_n_chan_done(chan, 0) from

channel_closed(). Fixes bug 9776; bugfix on 0.2.4.17-rc.

o Minor bugfixes (on 0.2.4.x):

- Correctly log long IPv6 exit policies, instead of truncating them

or reporting an error. Fixes bug 9596; bugfix on 0.2.4.7-alpha.

- Our default TLS ecdhe groups were backwards: we meant to be using

P224 for relays (for performance win) and P256 for bridges (since

it is more common in the wild). Instead we had it backwards. After

reconsideration, we decided that the default should be P256 on all

hosts, since its security is probably better, and since P224 is

reportedly used quite little in the wild. Found by "skruffy" on

IRC. Fix for bug 9780; bugfix on 0.2.4.8-alpha.

- Free directory authority certificate download statuses on exit

rather than leaking them. Fixes bug 9644; bugfix on 0.2.4.13-alpha.

o Minor bugfixes (on 0.2.3.x and earlier):

- If the guard we choose first doesn't answer, we would try the

second guard, but once we connected to the second guard we would

abandon it and retry the first one, slowing down bootstrapping.

The fix is to treat all our initially chosen guards as acceptable

to use. Fixes bug 9946; bugfix on 0.1.1.11-alpha.

- Fix an assertion failure that would occur when disabling the

ORPort setting on a running Tor process while accounting was

enabled. Fixes bug 6979; bugfix on 0.2.2.18-alpha.

- When examining the list of network interfaces to find our address,

do not consider non-running or disabled network interfaces. Fixes

bug 9904; bugfix on 0.2.3.11-alpha. Patch from "hantwister".

- Avoid an off-by-one error when checking buffer boundaries when

formatting the exit status of a pluggable transport helper.

This is probably not an exploitable bug, but better safe than

sorry. Fixes bug 9928; bugfix on 0.2.3.18-rc. Bug found by

Pedro Ribeiro.

o Minor features (protecting client timestamps):

- Clients no longer send timestamps in their NETINFO cells. These were

not used for anything, and they provided one small way for clients

to be distinguished from each other as they moved from network to

network or behind NAT. Implements part of proposal 222.

- Clients now round timestamps in INTRODUCE cells down to the nearest

10 minutes. If a new Support022HiddenServices option is set to 0, or

if it's set to "auto" and the feature is disabled in the consensus,

the timestamp is sent as 0 instead. Implements part of proposal 222.

- Stop sending timestamps in AUTHENTICATE cells. This is not such

a big deal from a security point of view, but it achieves no actual

good purpose, and isn't needed. Implements part of proposal 222.

- Reduce down accuracy of timestamps in hidden service descriptors.

Implements part of proposal 222.

o Minor features (other):

- Improve the circuit queue out-of-memory handler. Previously, when

we ran low on memory, we'd close whichever circuits had the most

queued cells. Now, we close those that have the *oldest* queued

cells, on the theory that those are most responsible for us

running low on memory. Based on analysis from a forthcoming paper

by Jansen, Tschorsch, Johnson, and Scheuermann. Fixes bug 9093.

- Generate bootstrapping status update events correctly when fetching

microdescriptors. Fixes bug 9927.

- Update to the October 2 2013 Maxmind GeoLite Country database.

o Documentation fixes:

- Clarify the usage and risks of setting the ContactInfo torrc line

for your relay or bridge. Resolves ticket 9854.

- Add anchors to the manpage so we can link to the html version of

the documentation for specific options. Resolves ticket 9866.

- Replace remaining references to DirServer in man page and

log entries. Resolves ticket 10124.