We need to record different statistics at point of timeout, vs the point
of forcible closing.
Also, give some better names to constants and state file variables
to indicate they are not dealing with timeouts, but abandoned circuits.
Most of the changes here are switches to use APIs available on Windows
CE. The most pervasive change is that Windows CE only provides the
wide-character ("FooW") variants of most of the windows function, and
doesn't support the older ASCII verions at all.
This patch will require use of the wcecompat library to get working
versions of the posix-style fd-based file IO functions.
[commit message by nickm]
There are now four ways that CBT can be disabled:
1. Network-wide, with the cbtdisabled consensus param.
2. Via config, with "LearnCircuitBuildTimeout 0"
3. Via config, with "AuthoritativeDirectory 1"
4. Via a state file write failure.
From http://archives.seul.org/tor/relays/Mar-2010/msg00006.html :
As I understand it, the bug should show up on relays that don't set
Address to an IP address (so they need to resolve their Address
line or their hostname to guess their IP address), and their
hostname or Address line fails to resolve -- at that point they'll
pick a random 4 bytes out of memory and call that their address. At
the same time, relays that *do* successfully resolve their address
will ignore the result, and only come up with a useful address if
their interface address happens to be a public IP address.
All other bandwidthrate settings are restricted to INT32_MAX, but
this check was forgotten for PerConnBWRate and PerConnBWBurst. Also
update the manpage to reflect the fact that specifying a bandwidth
in terabytes does not make sense, because that value will be too
large.
On Windows, we don't have a notion of ~ meaning "our homedir", so we
were deliberately using an #ifdef to avoid calling expand_filename()
in multiple places. This is silly: The right place to turn a function
into a no-op on a single platform is in the function itself, not in
every single call-site.
Tor has tor_lookup_hostname(), which prefers ipv4 addresses automatically.
Bug 1244 occured because gethostbyname() returned an ipv6 address, which
Tor cannot handle currently. Fixes bug 1244; bugfix on 0.0.2pre25.
Reported by Mike Mestnik.
Specifically, there are two cases: a) are we willing to start a new
circuit at a node not in your ExitNodes config option, and b) are we
willing to make use of a circuit that's already established but has an
unsuitable exit.
Now we discard all your circuits when you set ExitNodes, so the only
way you could end up with an exit circuit that ends at an unsuitable
place is if we explicitly ran out of exit nodes, StrictNodes was 0,
and we built this circuit to solve a stream that needs solving.
Fixes bug in dc322931, which would ignore the just-built circuit because
it has an unsuitable exit.
The HSAuthorityRecordStats option was used to track statistics of overall
hidden service usage on the version 0 hidden service authorities. With the
version 2 hidden service directories being deployed and version 0
descriptors being phased out, these statistics are not as useful anymore.
Goodbye, you fine piece of software; my first major code contribution to
Tor.
The new rule is: safe_str_X() means "this string is a piece of X
information; make it safe to log." safe_str() on its own means
"this string is a piece of who-knows-what; make it safe to log".
The rule is now: take the value from the CircuitPriorityHalflife
config option if it is set. If it zero, disable the cell_ewma
algorithm. If it is set, use it to calculate the scaling factor.
If it is not set, look for a CircPriorityHalflifeMsec parameter in the
consensus networkstatus. If *that* is zero, then disable the cell_ewma
algorithm; if it is set, use it to calculate the scaling factor.
If it is not set at all, disable the algorithm.
There are two big changes here:
- We store active circuits in a priority queue for each or_conn,
rather than doing a linear search over all the active circuits
before we send each cell.
- Rather than multiplying every circuit's cell-ewma by a decay
factor every time we send a cell (thus normalizing the value of a
current cell to 1.0 and a past cell to alpha^t), we instead
only scale down the cell-ewma every tick (ten seconds atm),
normalizing so that a cell sent at the start of the tick has
value 1.0).
Each circuit is ranked in terms of how many cells from it have been
relayed recently, using a time-weighted average.
This patch has been tested this on a private Tor network on PlanetLab,
and gotten improvements of 12-35% in time it takes to fetch a small
web page while there's a simultaneous large data transfer going on
simultaneously.
[Commit msg by nickm based on mail from Ian Goldberg.]
Some *_free functions threw asserts when passed NULL. Now all of them
accept NULL as input and perform no action when called that way.
This gains us consistence for our free functions, and allows some
code simplifications where an explicit null check is no longer necessary.
New config option "CircuitStreamTimeout" to override our internal
timeout schedule for how many seconds until we detach a stream from
a circuit and try a new circuit. If your network is particularly
slow, you might want to set this to a number like 60.
This commit implements a new config option: 'DisableAllSwap'
This option probably only works properly when Tor is started as root.
We added two new functions: tor_mlockall() and tor_set_max_memlock().
tor_mlockall() attempts to mlock() all current and all future memory pages.
For tor_mlockall() to work properly we set the process rlimits for memory to
RLIM_INFINITY (and beyond) inside of tor_set_max_memlock().
We behave differently from mlockall() by only allowing tor_mlockall() to be
called one single time. All other calls will result in a return code of 1.
It is not possible to change DisableAllSwap while running.
A sample configuration item was added to the torrc.complete.in config file.
A new item in the man page for DisableAllSwap was added.
Thanks to Moxie Marlinspike and Chris Palmer for their feedback on this patch.
Please note that we make no guarantees about the quality of your OS and its
mlock/mlockall implementation. It is possible that this will do nothing at all.
It is also possible that you can ulimit the mlock properties of a given user
such that root is not required. This has not been extensively tested and is
unsupported. I have included some comments for possible ways we can handle
this on win32.
The code for these was super-wrong, but will only break things when we
reset an option on a platform where sizeof(time_t) is different from
sizeof(int).
We want it to be under our control so it doesn't mess
up initialization. This is likely the cause for
the bug the previous assert-adding commit (09a75ad) was
trying to address.
Using CircuitBuildTimeout is prone to issues with SIGHUP, etc.
Also, shuffle the circuit build times array after loading it
in so that newer measurements don't replace chunks of
similarly timed measurements.
When we added support for fractional units (like 1.5 MB) I broke
support for giving units with no space (like 2MB). This patch should
fix that. It also adds a propoer tor_parse_double().
Fix for bug 1076. Bugfix on 0.2.2.1-alpha.
Note that unlike subversion revision numbers, it isn't meaningful to
compare these for anything but equality. We define a sort-order anyway,
in case one of these accidentally slips into a recommended-versions
list.
Relays no longer publish a new server descriptor if they change
their MaxAdvertisedBandwidth config option but it doesn't end up
changing their advertised bandwidth numbers. Bugfix on 0.2.0.28-rc;
fixes bug 1026. Patch from Sebastian.
