This is ticket 2479. Roger's original explanation was:
We have a series of bugs where relays publish a descriptor within
12 hours of their last descriptor, but the authorities drop it
because it's not different "enough" from the last one and it's
too close to the last one.
The original goal of this idea was to a) reduce the number of new
descriptors authorities accept (and thus have to store) and b)
reduce the total number of descriptors that clients and mirrors
fetch. It's a defense against bugs where relays publish a new
descriptor every minute.
Now that we're putting out one consensus per hour, we're doing
better at the total damage that can be caused by 'b'.
There are broader-scale design changes that would help here, and
we've had a trac entry open for years about how relays should
recognize that they're not in the consensus, or recognize when
their publish failed, and republish sooner.
In the mean time, I think we should change some of the parameters
to make the problem less painful.
When we started RefuseUnknownExits back in 0.2.2.11-alpha, we
started making exits act like they cache directory info (since they
need an up-to-date idea of who is really a router). But this
included fetching needless (unrecognized) authorities' certs, which
doesn't make any sense for them.
This is related to, but not necessarily the same as, the issue that
Ian reported for bug #2297.
(This patch is based on a patch from a user who I believe has asked
not to be named. If I'm wrong about that, please add the
appropriate name onto the changelog.)
==
Nick here. I tweaked this patch a little to make it apply cleanly to
master, to extract some common code into a function, and to replace
snprintf with tor_snprintf.
-- nickm
Specifically, it was a fix on 33e2053ebc, where we introduced the
WRA_* and ROUTER_* codes for dirserv_add_descriptor. Previously, we
had checked for a _negative_ return from dirserv_add_descriptor, which
meant "rejected". An insufficiently new descriptor would give a
0-valued return. But when we switched from numbers to enums, we got
this check wrong and had init_keys() give an error whenever the
descriptor wasn't accepted.
This mitigates an attack proposed by wanoskarnet, in which all of a
client's bridges collude to restrict the exit nodes that the client
knows about. Fixes bug 5343.
Since 0.2.3.1-alpha, we've supported the Linux extensions to socket(),
open(), socketpair(), and accept() that enable us to create an fd and
make it close-on-exec with a single syscall. This not only saves us a
syscall (big deal), but makes us less vulnerable to race conditions
where we open a socket and then exec before we can make it
close-on-exec.
But these extensions are not supported on all Linuxes: They were added
between 2.6.23 or so and 2.6.28 or so. If you were to build your Tor
against a recent Linux's kernel headers, and then run it with a older
kernel, you would find yourselve unable to open sockets. Ouch!
The solution here is that, when one of these syscalls fails with
EINVAL, we should try again in the portable way. This adds an extra
syscall in the case where we built with new headers and are running
with old ones, but it will at least allow Tor to work.
Fixes bug 5112; bugfix on 0.2.3.1-alpha.
The big change here is a patch (first added to Libevent by Ed Day)
to make sure that the CreateProcess forked-test trick works even
when the main test program is invoked without its .exe suffix.
Previously we'd been using "we have clock_gettime()" as a proxy for
"we need -lrt to link a static libevent". But that's not really
accurate: we should only add -lrt if searching for clock_gettime
function adds -lrt to our libraries.
in Makefile.am, we used it without quoting it, causing build failure if
your openssl/sed/sha1sum happened to live in a directory with a space in
it (very common on windows)
This reverts commit 55e8cae815.
The conversation from irc:
> weasel: i had intended to leave torrc.sample.in alone in maint-0.2.2,
since i don't want to make all your stable users have to deal with
a torrc change. but nickm changed it. is it in fact the case that a
change in that file means a change in the deb?
<weasel> it means you'll prompt every single user who ever touched
their torrc
<weasel> and they will be asked if they like your new version better
than what they have right now
<weasel> so it's not great
Instead I changed the website to redirect requests for the tor-manual
URL listed in maint-0.2.2's torrc.sample.in so the link will still work.
If we don't do this, [::] can be interpreted to mean all v4 and all
v6 addresses. Found by dcf. Fixes bug 4760. See RFC 3493 section
5.3 for more info.
There was one MS_WINDOWS that remained because it wasn't on a macro
line; a few remaining uses (and the definition!) in configure.in;
and a now-nonsensical stanza of eventdns_tor.h that previously
defined 'WIN32' if it didn't exist.
Previously the client would ask the bridge for microdescriptors, which are
only supported in 0.2.3.x and later, and then fail to bootstrap when it
didn't get the answers it wanted. Fixes bug 4013; bugfix on 0.2.3.2-alpha.
The fix here is to revert to using normal descriptors if any of our
bridges are known to not support microdescs. This is not ideal, a) because
we'll start downloading a microdesc consensus as soon as we get a bridge
descriptor, and that will waste time if we later get a bridge descriptor
that tells us we don't like microdescriptors; and b) by changing our mind
we're leaking to our other bridges that we have an old-version bridge.
The alternate fix would have been to change
we_use_microdescriptors_for_circuits() to ask if *any* of our bridges
can support microdescriptors, and then change the directory logic that
picks a bridge to only select from those that do. For people living in
the future, where 0.2.2.x is obsolete, there won't be a difference.
Note that in either of these potential fixes, we have risk of oscillation
if our one funny-looking bridges goes away / comes back.
This option seems to be supported all the way back to at least 10.4, so
enabling it for OS X in general should be fine. If not, someone will
yell.
With no libs statically linked, that's a 3% win in binary size, with
just libevent linked statically, this gives us an advantage of 5% in
terms of binary size, and with libevent and openssl statically linked,
we gain over 18% or over 500KB.
Implements ticket 2915.
These were found by looking for tor_snprintf() instances that were
followed closely by tor_strdup(), though I probably converted some
other snprintfs as well.
(To ensure correctness, in every case, make sure that the temporary
variable is deleted, renamed, or lowered in scope, so we can't have
any bugs related to accidentally relying on the no-longer-filled
variable.)
To solve bug 4779, we want to avoid OpenSSL 1.0.0's counter mode.
But Fedora (and maybe others) lie about the actual OpenSSL version,
so we can't trust the header to tell us if it's safe.
Instead, let's do a run-time test to see whether it's safe, and if
not, use our built-in version.
fermenthor contributed a pretty essential fixup to this patch. Thanks!
When we have an effective bandwidthrate configured so that we cannot
exceed our bandwidth limit in one accounting interval, don't disable
advertising the dirport. Implements ticket 2434.
Fixes bug 4413; bugfix on xxxx.
Hostname components cannot be larger than 63 characters.
This simple check makes certain randlen cannot overflow rand_bytes_len.
We used to do this as a workaround for older Tors, but now it's never
the correct thing to do (especially since anything that didn't
understand RELAY_EARLY is now deprecated hard).
This patch should make us reject every Tor that was vulnerable to
CVE-2011-0427. Additionally, it makes us reject every Tor that couldn't
handle RELAY_EARLY cells, which helps with proposal 110 (#4339).
Previously we required 1.0.0, but there was a bug in the 1.0.0 counter
mode. Found by Pascal. Fixes bug 4779.
A more elegant solution would be good here if somebody has time to code
one.
Back in #1240, r1eo linked to information about how this could happen
with older Linux kernels in response to nmap. Bugs #4545 and #4547
are about how our approach to trying to deal with this condition was
broken and stupid. Thanks to wanoskarnet for reminding us about #1240.
This is a fix for the abovementioned bugs, and is a bugfix on
0.1.0.3-rc.
Preprocessor directives should not be put inside the arguments
of a macro. This is not supported on older GCC releases (< 3.3)
thus broke compilation on Haiku (running gcc2).
--enable-gcc-warnings enables two warnings that clang doesn't support,
so the build fails. We had hoped clang 3.0 would add those, but it
didn't, so let's just always disable those warnings when building with
clang. We can still fix it later once they add support
If a relay is dormant at startup, it will call init_keys before
crypto_set_tls_dh_prime. This is bad. Let's make it not so bad, because
someday it *will* happen again.
Conflicts:
src/or/connection_or.c
The conflict in src/or/connection_or.c is resolved by taking the
version in master, since e27a26d5 already fixed bug 4531 on master.
This merge just adds the changes file from 0.2.2.
