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.
When the bandwidth-weights branch added the "directory-footer"
token, and began parsing the directory footer at the first
occurrence of "directory-footer", it made it possible to fool the
parsing algorithm into accepting unsigned data at the end of a
consensus or vote. This patch fixes that bug by treating the footer
as starting with the first "directory-footer" or the first
"directory-signature", whichever comes first.
Treat strings returned from signed_descriptor_get_body_impl() as not
NUL-terminated. Since the length of the strings is available, this is
not a big problem.
Discovered by rieo.
Another dereference-then-NULL-check sequence. No reports of this bug
triggered in the wild. Fixes bugreport 1256.
Thanks to ekir for discovering and reporting this bug.
Fix a dereference-then-NULL-check sequence. This bug wasn't triggered
in the wild, but we should fix it anyways in case it ever happens.
Also make sure users get a note about this being a bug when they
see it in their log.
Thanks to ekir for discovering and reporting this bug.
We used to only zero the first ptrsize bytes of the cipher. Since
cipher is large enough, we didn't zero too many bytes. Discovered
and fixed by ekir. Fixes bug 1254.
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.
Fix a dereference-then-NULL-check sequence. This bug wasn't triggered
in the wild, but we should fix it anyways in case it ever happens.
Also make sure users get a note about this being a bug when they
see it in their log.
Thanks to ekir for discovering and reporting this bug.
We used to only zero the first ptrsize bytes of the cipher. Since
cipher is large enough, we didn't zero too many bytes. Discovered
and fixed by ekir. Fixes bug 1254.
Spec conformance issue: The code didn't force the network-status-version
token to be the first token in a v3 vote or consensus.
Problem discovered by Parakeep.
We need to use evdns_add_server_port_with_base() when configuring
our DNS listener, because libevent segfaults otherwise. Add a macro
in compat_libevent.h to pick the correct implementation depending
on the libevent version.
Fixes bug 1143, found by SwissTorExit
We implemented ratelimiting for warnings going into the logfile, but didn't
rate-limit controller events. Now both log warnings and controller events
are rate-limited.
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.
The problem was that we didn't allocate enough memory on 32-bit
platforms with 64-bit time_t. The memory leak occured every time
we fetched a hidden service descriptor we've fetched before.
exit_policy_is_general_exit() assumed that there are no redundancies
in the passed policy, in the sense that we actively combine entries
in the policy to really get rid of any redundancy. Since we cannot
do that without massively rewriting the policy lines the relay
operators set, fix exit_policy_is_general_exit().
Fixes bug 1238, discovered by Martin Kowalczyk.
We need to do this because Apple doesn't update its dev-tools headers
when it updates its libraries in a security patch. On the bright
side, this might get us out of shipping a statically linked OpenSSL on
OSX.
May fix bug 1225.
[backported]
We need to do this because Apple doesn't update its dev-tools headers
when it updates its libraries in a security patch. On the bright
side, this might get us out of shipping a statically linked OpenSSL on
OSX.
May fix bug 1225.
We accidentally freed the internal buffer for bridge stats when we
were writing the bridge stats file or honoring a control port
request for said data. Change the interfaces for
geoip_get_bridge_stats* to prevent these problems, and remove the
offending free/add a tor_strdup.
Fixes bug 1208.
The OutboundBindAddress option is useful for making sure that all of
your outbond connections use a given interface. But when connecting
to 127.0.0.1 (or ::1 even) it's important to actually have the
connection come _from_ localhost, since lots of programs running on
localhost use the source address to authenticate that the connection
is really coming from the same host.
Our old code always bound to OutboundBindAddress, whether connecting
to localhost or not. This would potentially break DNS servers on
localhost, and socks proxies on localhost. This patch changes the
behavior so that we only look at OutboundBindAddress when connecting
to a non-loopback address.
...to let us
rate-limit client connections as they enter the network. It's
controlled in the consensus so we can turn it on and off for
experiments. It's starting out off. Based on proposal 163.
Fix statistics on client numbers by country as seen by bridges that were
broken in 0.2.2.1-alpha. Also switch to reporting full 24-hour intervals
instead of variable 12-to-48-hour intervals.
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.
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.
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.
On this OSX version, there is a stub mlockall() function
that doesn't work, *and* the declaration for it is hidden by
an '#ifdef _P1003_1B_VISIBLE'. This would make autoconf
successfully find the function, but our code fail to build
when no declaration was found.
This patch adds an additional test for the declaration.
To fix a major security problem related to incorrect use of
SSL/TLS renegotiation, OpenSSL has turned off renegotiation by
default. We are not affected by this security problem, however,
since we do renegotiation right. (Specifically, we never treat a
renegotiated credential as authenticating previous communication.)
Nevertheless, OpenSSL's new behavior requires us to explicitly
turn renegotiation back on in order to get our protocol working
again.
Amusingly, this is not so simple as "set the flag when you create
the SSL object" , since calling connect or accept seems to clear
the flags.
For belt-and-suspenders purposes, we clear the flag once the Tor
handshake is done. There's no way to exploit a second handshake
either, but we might as well not allow it.
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.
If your relay can't keep up with the number of incoming create cells, it
would log one warning per failure into your logs. Limit warnings to 1 per
minute.
If all authorities restart at once right before a consensus vote, nobody
will vote about "Running", and clients will get a consensus with no usable
relays. Instead, authorities refuse to build a consensus if this happens.
When we tried to use the deprecated non-threadsafe evdns
interfaces in Libevent 2 without using the also-deprecated
event_init() interface, Libevent 2 would sensibly crash, since it
has no guess where to find the Libevent library.
Here we use the evdns_base_*() functions instead if they're
present, and fake them if they aren't.
This is a possible fix for bug 1023, where if we vote (or make a v2
consensus networkstatus) right after we come online, we can call
rep_hist_note_router_unreachable() on every router we haven't connected
to yet, and thereby make all their uptime values reset.
Don't count one-hop circuits when we're estimating how long it
takes circuits to build on average. Otherwise we'll set our circuit
build timeout lower than we should. Bugfix on 0.2.2.2-alpha.
Directory authorities now reject Tor relays with versions less than
0.1.2.14. This step cuts out four relays from the current network,
none of which are very big.
- Avoid memmoving 0 bytes which might lead to compiler warnings.
- Don't require relays to be entry node AND bridge at the same to time to
record clients.
- Fix a memory leak when writing dirreq-stats.
- Don't say in the stats files that measurement intervals are twice as long
as they really are.
- Reduce minimum observation time for requests to 12 hours, or we might
never record usage.
- Clear exit stats correctly after writing them, or we accumulate old stats
over time.
- Reset interval start for buffer stats, too.
The big change is to add a function to display the current SSL handshake
state, and to log it everywhere reasonable. (A failure in
SSL23_ST_CR_SRVR_HELLO_A is different from one in
SSL3_ST_CR_SESSION_TICKET_A.)
This patch also adds a new log domain for OR handshaking, so you can pull out
all the handshake log messages without having to run at debug for everything.
For example, you'd just say "log notice-err [handshake]debug-err file
tor.log".
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.
To further attempt to fix bug 1090, make sure connection_ap_can_use_exit
always returns 0 when the chosen exit router is excluded. This should fix
bug1090.
When we excluded some Exits, we were sometimes warning the user that we
were going to use the node regardless. Many of those warnings were in
fact bogus, because the relay in question was not used to connect to
the outside world.
Based on patch by Rotor, thanks!
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.
This code adds a new field to vote on: "params". It consists of a list of
sorted key=int pairs. The output is computed as the median of all the
integers for any key on which anybody voted.
Improved with input from Roger.
Adding the same vote to a networkstatus consensus leads to a memory leak
on the client side. Fix that by only using the first vote from any given
voter, and ignoring the others.
Problem found by Rotor, who also helped writing the patch. Thanks!
A vote may only contain exactly one signature. Make sure we reject
votes that violate this.
Problem found by Rotor, who also helped writing the patch. Thanks!
Fix an obscure bug where hidden services on 64-bit big-endian
systems might mis-read the timestamp in v3 introduce cells, and
refuse to connect back to the client. Discovered by "rotor".
Bugfix on 0.2.1.6-alpha.
Add a "getinfo status/accepted-server-descriptor" controller
command, which is the recommended way for controllers to learn
whether our server descriptor has been successfully received by at
least on directory authority. Un-recommend good-server-descriptor
getinfo and status events until we have a better design for them.
We were telling the controller about CHECKING_REACHABILITY and
REACHABILITY_FAILED status events whenever we launch a testing
circuit or notice that one has failed. Instead, only tell the
controller when we want to inform the user of overall success or
overall failure. Bugfix on 0.1.2.6-alpha. Fixes bug 1075. Reported
by SwissTorExit.
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.
We were triggering a CLOCK_SKEW controller status event whenever
we connect via the v2 connection protocol to any relay that has
a wrong clock. Instead, we should only inform the controller when
it's a trusted authority that claims our clock is wrong. Bugfix
on 0.2.0.20-rc; starts to fix bug 1074. Reported by SwissTorExit.
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.
If any the v3 certs we download are unparseable, we should actually
notice the failure so we don't retry indefinitely. Bugfix on 0.2.0.x;
reported by "rotator".
Once we had called log_free_all(), anything that tried to log a
message (like a failed tor_assert()) would fail like this:
1. The logging call eventually invokes the _log() function.
2. _log() calls tor_mutex_lock(log_mutex).
3. tor_mutex_lock(m) calls tor_assert(m).
4. Since we freed the log_mutex, tor_assert() fails, and tries to
log its failure.
5. GOTO 1.
Now we allocate the mutex statically, and never destroy it on
shutdown.
Bugfix on 0.2.0.16-alpha, which introduced the log mutex.
This bug was found by Matt Edman.
The more verbose logs that were added in ee58153 also include a string
that might not have been initialized. This can lead to segfaults, e.g.,
when setting up private Tor networks. Initialize this string with NULL.
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.
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.
Specifically, every time we get a create cell but we have so many already
queued that we refuse it.
Bugfix on 0.2.0.19-alpha; fixes bug 1034. Reported by BarkerJr.
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.
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.
This new option will allow clients to download the newest fresh consensus
much sooner than they normally would do so, even if they previously set
FetchDirInfoEarly. This includes a proper ChangeLog entry and an updated man
page.
The internal error "could not find intro key" occurs when we want to send
an INTRODUCE1 cell over a recently finished introduction circuit and think
we built the introduction circuit with a v2 hidden service descriptor, but
cannot find the introduction key in our descriptor.
My first guess how we can end up in this situation is that we are wrong in
thinking that we built the introduction circuit based on a v2 hidden
service descriptor. This patch checks if we have a v0 descriptor, too, and
uses that instead.
