In rare cases, we could cannibalize a one-hop circuit, ending up
with a two-hop circuit. This circuit would not be actually used,
but we should prevent its creation in the first place.
Thanks to outofwords and swissknife for helping to analyse this.
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".
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.
Avoid crashing if the client is trying to upload many bytes and the
circuit gets torn down at the same time, or if the flip side
happens on the exit relay. Bugfix on 0.2.0.1-alpha; fixes bug 1150.
If the networkstatus consensus tells us that we should use a
negative circuit package window, ignore it. Otherwise we'll
believe it and then trigger an assert.
Also, change the interface for networkstatus_get_param() so we
don't have to lookup the consensus beforehand.
Tor now reads the "circwindow" parameter out of the consensus,
and uses that value for its circuit package window rather than the
default of 1000 cells. Begins the implementation of proposal 168.
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
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
Move n_addr, n_port, and n_conn_id_digest fields of circuit_t into a separately allocated extend_info_t. Saves 22 bytes per connected circuit_t on 32-bit platforms, and makes me more comfortable with using tor_addr_t in place of uint32_t n_addr.
svn:r16257
Patch from Christian Wilms: remove (HiddenService|Rend)(Exclude)?Nodes options. They never worked properly, and nobody seems to be using them. Resolves bug 754.
svn:r16144
Never allow a circuit to be created with the same circid as a circuit that has been marked for close. May be a fix for bug 779. Needs testing. Backport candidate.
svn:r16136
Fix all but 2 DOCDOC items; defer many XXX020s (particularly those where fixing them would fix no bugs at the risk of introducing some bugs).
svn:r13529
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
Initial attempts to track down bug 600, and refactor possibly offending code. 1) complain early if circuit state is set to OPEN when an onionskin is pending. 2) refactor onionskin field into one only used when n_conn is pending, and a separate onionskin field waiting for attention by a cpuworker. This might even fix the bug. More likely, it will make it fail with a more useful core.
svn:r13394
Refactor circuit_launch* functions to take a bitfield of flags rather than 4 separate nonconsecutive flags arguments. Also, note a possible but in circuit_find_to_cannibalize, which seems to be ignoring its purpose argument.
svn:r12948
