When you mean (a=b(c,d)) >= 0, you had better not say (a=b(c,d)>=0).
We did the latter, and so whenever CircPriorityHalflife was in the
consensus, it was treated as having a value of 1 msec (that is,
boolean true).
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.
- Refactor geoip.c by moving duplicate code into rotate_request_period().
- Don't leak memory when cleaning up cell queues.
- Make sure that exit_(streams|bytes_(read|written)) are initialized in all
places accessing these arrays.
- Read only the last block from *stats files and ensure that its timestamp
is not more than 25 hours in the past and not more than 1 hour in the
future.
- Stop truncating the last character when reading *stats files.
The only thing that's left now is to avoid reading whole *stats files into
memory.
Send circuit or stream sendme cells when our window has decreased
by 100 cells, not when it has decreased by 101 cells. Bug uncovered
by Karsten when testing the "reduce circuit window" performance
patch. Bugfix on the 54th commit on Tor -- from July 2002,
before the release of Tor 0.0.0. This is the new winner of the
oldest-bug prize.
The problem is that clients and hidden services are receiving
relay_early cells, and they tear down the circuit.
Hack #1 is for rendezvous points to rewrite relay_early cells to
relay cells. That way there are never any incoming relay_early cells.
Hack #2 is for clients and hidden services to never send a relay_early
cell on an established rendezvous circuit. That works around rendezvous
points that haven't upgraded yet.
Hack #3 is for clients and hidden services to not tear down the circuit
when they receive an inbound relay_early cell. We already refuse extend
cells at clients.
When determining how long directory requests take or how long cells spend
in queues, we were comparing timestamps on microsecond detail only to
convert results to second or millisecond detail later on. But on 32-bit
architectures this means that 2^31 microseconds only cover time
differences of up to 36 minutes. Instead, compare timestamps on
millisecond detail.
Changes to directory request statistics:
- Rename GEOIP statistics to DIRREQ statistics, because they now include
more than only GeoIP-based statistics, whereas other statistics are
GeoIP-dependent, too.
- Rename output file from geoip-stats to dirreq-stats.
- Add new config option DirReqStatistics that is required to measure
directory request statistics.
- Clean up ChangeLog.
Also ensure that entry guards statistics have access to a local GeoIP
database.
Fix an edge case where a malicious exit relay could convince a
controller that the client's DNS question resolves to an internal IP
address. Bug found and fixed by "optimist"; bugfix on 0.1.2.8-beta.
Fix an edge case where a malicious exit relay could convince a
controller that the client's DNS question resolves to an internal IP
address. Bug found and fixed by "optimist"; bugfix on 0.1.2.8-beta.
The subversion $Id$ fields made every commit force a rebuild of
whatever file got committed. They were not actually useful for
telling the version of Tor files in the wild.
svn:r17867
"connecting" and it receives an "end" relay cell, the exit relay
would silently ignore the end cell and not close the stream. If
the client never closes the circuit, then the exit relay never
closes the TCP connection. Bug introduced in Tor 0.1.2.1-alpha;
reported by "wood".
svn:r17625
The "ClientDNSRejectInternalAddresses" config option wasn't being
consistently obeyed: if an exit relay refuses a stream because its
exit policy doesn't allow it, we would remember what IP address
the relay said the destination address resolves to, even if it's
an internal IP address. Bugfix on 0.2.0.7-alpha; patch by rovv.
svn:r17135
Initial conversion of uint32_t addr to tor_addr_t addr in connection_t and related types. Most of the Tor wire formats using these new types are in, but the code to generate and use it is not. This is a big patch. Let me know what it breaks for you.
svn:r16435
Part of fix for bug 617: allow connection_ap_handshake_attach_circuit() to mark connections, to avoid double-mark warnings. Note that this is an incomplete refactoring.
svn:r14066
Re-tune mempool parametes based on testing on peacetime: use smaller chuncks, free them a little more aggressively, and try very hard to concentrate allocations on fuller chunks. Also, lots of new documentation.
svn:r13484
Add a couple of (currently disabled) strategies for trying to avoid using too much ram in memory pools: prefer putting new cells in almost-full chunks, and be willing to free the last empty chunk if we have not needed it for a while. Also add better output to mp_pool_log_status to track how many mallocs a given memory pool strategy is saving us, so we can tune the mempool parameters.
svn:r13428
Be more thorough about memory poisoning and clearing. Add an in-place version of aes_crypt in order to remove a memcpy from relay_crypt_one_payload.
svn:r13414
Tor can warn and/or refuse connections to ports commonly used with
vulnerable-plaintext protocols.
We still need to figure out some good defaults for them.
svn:r13198
Use reference-counting to avoid allocating a zillion little addr_policy_t objects. (This is an old patch that had been sitting on my hard drive for a while.)
svn:r13017
Add a new ClientDNSRejectInternalAddresses option (default: on) to refuse to believe that any address can map to or from an internal address. This blocks some kinds of potential browser-based attacks, especially on hosts using DNSPort. Also clarify behavior in some comments. Backport candiate?
svn:r11287
Fix warnings from -Wunsafe-loop-optimizations, which incidentally turned up a logic bug in connection_or_flush_from_first_active_circuit that would overcount the number of cells flushed.
svn:r10199
