Commit Graph

4287 Commits

Author SHA1 Message Date
Andrea Shepard
2905a3484e Changes file for random exponential backoffs 2016-06-18 16:32:17 +00:00
cypherpunks
94762e37b9 Use the Autoconf macro AC_USE_SYSTEM_EXTENSIONS
The Autoconf macro AC_USE_SYSTEM_EXTENSIONS defines preprocessor macros
which turn on extensions to C and POSIX. The macro also makes it easier
for developers to use the extensions without needing (or forgetting) to
define them manually.

The macro can be safely used because it was introduced in Autoconf 2.60
and Tor requires Autoconf 2.63 and above.
2016-06-17 10:17:44 -04:00
David Goulet
ab35f9de46 Correctly close intro circuit when deleting ephemeral HS
When deleting an ephemeral HS, we were only iterating on circuit with an
OPEN state. However, it could be possible that an intro point circuit didn't
reached the open state yet.

This commit makes it that we close the circuit regardless of its state
except if it was already marked for close.

Fixes #18604

Signed-off-by: David Goulet <dgoulet@torproject.org>
2016-06-16 13:09:24 -04:00
Nick Mathewson
41cb26c169 Correct the rounding behavior on tv_mdiff.
Fix for bug 19428.
2016-06-16 10:16:04 -04:00
David Goulet
c7f1b46a10 Perform cache lookup when FetchHidServDescriptors is set
The FetchHidServDescriptors check was placed before the descriptor cache
lookup which made the option not working because it was never using the
cache in the first place.

Fixes #18704

Patched-by: twim
Signef-off-by: David Goulet <dgoulet@torproject.org>
2016-06-15 10:04:07 -04:00
Nick Mathewson
df4fa92a88 Merge branch 'maint-0.2.8' 2016-06-14 12:17:24 -04:00
Yawning Angel
b217e4ac65 Bug 19406: Add a changes file. 2016-06-14 12:13:09 -04:00
Nick Mathewson
a427a7c479 Merge branch 'maint-0.2.8' 2016-06-13 14:21:47 -04:00
Nick Mathewson
60b8aaefa1 lintChanges fixes 2016-06-13 13:57:03 -04:00
Nick Mathewson
6a7d11f38a Merge branch 'maint-0.2.8' 2016-06-13 10:49:24 -04:00
Nick Mathewson
2ee3dbe801 Merge branch 'maint-0.2.7' into maint-0.2.8 2016-06-13 10:49:05 -04:00
Nick Mathewson
80089c9e7c Merge branch 'maint-0.2.6' into maint-0.2.7 2016-06-13 10:48:56 -04:00
Nick Mathewson
b4bb88606e Merge branch 'maint-0.2.5' into maint-0.2.6 2016-06-13 10:48:48 -04:00
Nick Mathewson
f25f7b759c Merge branch 'maint-0.2.4' into maint-0.2.5 2016-06-13 10:48:35 -04:00
Karsten Loesing
c14c662758 Update geoip and geoip6 to the June 7 2016 database. 2016-06-12 11:35:50 +02:00
Nick Mathewson
ada5668c5e Merge remote-tracking branch 'public/bug19203_027' into maint-0.2.8 2016-06-11 10:16:00 -04:00
Nick Mathewson
d6b2af7a3a Merge branch 'bug19180_easy_squashed' 2016-06-11 10:15:40 -04:00
Nick Mathewson
9bbd6502f0 Use autoconf, not gcc version, to decide which warnings we have
This gives more accurate results under Clang, which can only help us
detect more warnings in more places.

Fixes bug 19216; bugfix on 0.2.0.1-alpha
2016-06-11 10:11:53 -04:00
Nick Mathewson
b14c1f4082 Merge remote-tracking branch 'public/bug19203_027' into HEAD 2016-06-11 10:11:44 -04:00
Nick Mathewson
c274f825da Merge remote-tracking branch 'asn/bug17688' 2016-06-11 10:07:15 -04:00
George Kadianakis
36dd9538d9 Don't rely on consensus parameter to use a single guard. 2016-06-07 17:22:47 +03:00
Nick Mathewson
c19a3d1bf8 Merge branch 'maint-0.2.8' 2016-06-06 10:18:07 -04:00
Nick Mathewson
6eeedc02d8 Use directory_must_use_begindir to predict we'll surely use begindir
Previously, we used !directory_fetches_from_authorities() to predict
that we would tunnel connections.  But the rules have changed
somewhat over the course of 0.2.8
2016-06-02 10:40:39 -04:00
Nick Mathewson
b458a81cc5 Merge branch 'maint-0.2.8' 2016-06-02 10:13:35 -04:00
Nick Mathewson
a32ca313c4 Merge branch 'maint-0.2.7' into maint-0.2.8 2016-06-02 10:12:56 -04:00
Nick Mathewson
5854b19816 Use tor_sscanf, not sscanf, in test_util.c.
Fixes the 0.2.7 case of bug #19213, which prevented mingw64 from
working.
2016-06-02 10:11:29 -04:00
Nick Mathewson
bdc59e33c1 Fix a warning on unnamed nodes in node_get_by_nickname().
There was a > that should have been an ==, and a missing !.  These
together prevented us from issuing a warning in the case that a
nickname matched an Unnamed node only.

Fixes bug 19203; bugfix on 0.2.3.1-alpha.
2016-05-30 12:03:03 -04:00
Nick Mathewson
1e5ad15688 Merge remote-tracking branch 'arma/task19035-fixedup' 2016-05-27 13:22:16 -04:00
Nick Mathewson
617b920551 Merge remote-tracking branch 'public/hardening_flags_must_link' 2016-05-27 12:52:39 -04:00
Roger Dingledine
11d52a449c Disable GET /tor/bytes.txt and GETINFO dir-usage
Remove support for "GET /tor/bytes.txt" DirPort request, and
"GETINFO dir-usage" controller request, which were only available
via a compile-time option in Tor anyway.

Feature was added in 0.2.2.1-alpha. Resolves ticket 19035.
2016-05-27 11:15:21 -04:00
Nick Mathewson
a0dd836098 Merge remote-tracking branch 'public/ticket19044' 2016-05-27 10:39:34 -04:00
Nick Mathewson
437cbb17c2 Merge remote-tracking branch 'asn/feature19036' 2016-05-27 10:37:11 -04:00
Nick Mathewson
476714e1a4 Merge remote-tracking branch 'arma/bug18840' 2016-05-27 10:35:55 -04:00
Nick Mathewson
b7fac185a6 Merge branch 'maint-0.2.8' 2016-05-25 16:59:46 -04:00
Nick Mathewson
36b2b48308 Merge branch 'bug18668_028' into maint-0.2.8 2016-05-25 16:58:43 -04:00
Nick Mathewson
44ea3dc331 Merge branch 'maint-0.2.8' 2016-05-25 10:21:15 -04:00
Nick Mathewson
6d375f17fc Merge branch 'bug19161_028_v2' into maint-0.2.8 2016-05-25 10:17:26 -04:00
Nick Mathewson
a3ec811c2e Merge branch 'maint-0.2.8' 2016-05-25 09:27:47 -04:00
Nick Mathewson
fdfc528f85 Merge branch 'bug19152_024_v2' into maint-0.2.8 2016-05-25 09:26:45 -04:00
Nick Mathewson
c4c4380a5e Fix a dangling pointer issue in our RSA keygen code
If OpenSSL fails to generate an RSA key, do not retain a dangling
pointer to the previous (uninitialized) key value. The impact here
should be limited to a difficult-to-trigger crash, if OpenSSL is
running an engine that makes key generation failures possible, or if
OpenSSL runs out of memory. Fixes bug 19152; bugfix on
0.2.1.10-alpha. Found by Yuan Jochen Kang, Suman Jana, and Baishakhi
Ray.

This is potentially scary stuff, so let me walk through my analysis.
I think this is a bug, and a backport candidate, but not remotely
triggerable in any useful way.

Observation 1a:

Looking over the OpenSSL code here, the only way we can really fail in
the non-engine case is if malloc() fails.  But if malloc() is failing,
then tor_malloc() calls should be tor_asserting -- the only way that an
attacker could do an exploit here would be to figure out some way to
make malloc() fail when openssl does it, but work whenever Tor does it.

(Also ordinary malloc() doesn't fail on platforms like Linux that
overcommit.)

Observation 1b:

Although engines are _allowed_ to fail in extra ways, I can't find much
evidence online  that they actually _do_ fail in practice. More evidence
would be nice, though.

Observation 2:

We don't call crypto_pk_generate*() all that often, and we don't do it
in response to external inputs. The only way to get it to happen
remotely would be by causing a hidden service to build new introduction
points.

Observation 3a:

So, let's assume that both of the above observations are wrong, and the
attacker can make us generate a crypto_pk_env_t with a dangling pointer
in its 'key' field, and not immediately crash.

This dangling pointer will point to what used to be an RSA structure,
with the fields all set to NULL.  Actually using this RSA structure,
before the memory is reused for anything else, will cause a crash.

In nearly every function where we call crypto_pk_generate*(), we quickly
use the RSA key pointer -- either to sign something, or to encode the
key, or to free the key.  The only exception is when we generate an
intro key in rend_consider_services_intro_points().  In that case, we
don't actually use the key until the intro circuit is opened -- at which
point we encode it, and use it to sign an introduction request.

So in order to exploit this bug to do anything besides crash Tor, the
attacker needs to make sure that by the time the introduction circuit
completes, either:
  * the e, d, and n BNs look valid, and at least one of the other BNs is
    still NULL.
OR
  * all 8 of the BNs must look valid.

To look like a valid BN, *they* all need to have their 'top' index plus
their 'd' pointer indicate an addressable region in memory.

So actually getting useful data of of this, rather than a crash, is
going to be pretty damn hard.  You'd have to force an introduction point
to be created (or wait for one to be created), and force that particular
crypto_pk_generate*() to fail, and then arrange for the memory that the
RSA points to to in turn point to 3...8 valid BNs, all by the time the
introduction circuit completes.

Naturally, the signature won't check as valid [*], so the intro point
will reject the ESTABLISH_INTRO cell.  So you need to _be_ the
introduction point, or you don't actually see this information.

[*] Okay, so if you could somehow make the 'rsa' pointer point to a
different valid RSA key, then you'd get a valid signature of an
ESTABLISH_INTRO cell using a key that was supposed to be used for
something else ... but nothing else looks like that, so you can't use
that signature elsewhere.

Observation 3b:

Your best bet as an attacker would be to make the dangling RSA pointer
actually contain a fake method, with a fake RSA_private_encrypt
function that actually pointed to code you wanted to execute.  You'd
still need to transit 3 or 4 pointers deep though in order to make that
work.

Conclusion:

By 1, you probably can't trigger this without Tor crashing from OOM.

By 2, you probably can't trigger this reliably.

By 3, even if I'm wrong about 1 and 2, you have to jump through a pretty
big array of hoops in order to get any kind of data leak or code
execution.

So I'm calling it a bug, but not a security hole. Still worth
patching.
2016-05-25 09:23:57 -04:00
Nick Mathewson
6abceca182 Merge branch 'memarea_overflow_027_squashed' into maint-0.2.8 2016-05-25 09:22:02 -04:00
Nick Mathewson
be2d37ad3c Fix a pointer arithmetic bug in memarea_alloc()
Fortunately, the arithmetic cannot actually overflow, so long as we
*always* check for the size of potentially hostile input before
copying it.  I think we do, though.  We do check each line against
MAX_LINE_LENGTH, and each object name or object against
MAX_UNPARSED_OBJECT_SIZE, both of which are 128k.  So to get this
overflow, we need to have our memarea allocated way way too high up
in RAM, which most allocators won't actually do.

Bugfix on 0.2.1.1-alpha, where memarea was introduced.

Found by Guido Vranken.
2016-05-25 09:20:37 -04:00
Nick Mathewson
be3875cda2 Make sure that libscrypt_scrypt actually exists before using it.
Previously, if the header was present, we'd proceed even if the
function wasn't there.

Easy fix for bug 19161.  A better fix would involve trying harder to
find libscrypt_scrypt.
2016-05-24 10:31:02 -04:00
Nick Mathewson
2fa7a3af4c Make advisory-warnings on by default.
Add --enable-fatal-warnings to control -Werror.

Closes ticket 19044.
2016-05-23 14:39:56 -04:00
Nick Mathewson
2a884926c0 Merge remote-tracking branch 'dgoulet/bug19066_029_01' 2016-05-23 10:45:13 -04:00
Nick Mathewson
33ffeab694 Changes file for previous commit 2016-05-20 08:36:15 -04:00
Nick Mathewson
649785d464 Merge branch 'link_ftrapv_clang32' 2016-05-19 16:01:35 -04:00
Nick Mathewson
4a14c2cfc7 Merge branch 'maint-0.2.8' 2016-05-19 15:56:39 -04:00
Nick Mathewson
dd17df2253 lintchanges on 18809, and fix the bug number 2016-05-19 08:54:19 -04:00
Nick Mathewson
a7a44f2db0 Merge branch 'maint-0.2.8' 2016-05-19 08:29:58 -04:00