TROVE-2017-12. Severity: Medium
When choosing a random node for a circuit, directly use our router
descriptor to exclude ourself instead of the one in the global
descriptor list. That list could be empty because tor could be
downloading them which could lead to not excluding ourself.
Closes#21534
TROVE-2017-13. Severity: High.
In the unlikely case that a hidden service could be missing intro circuit(s),
that it didn't have enough directory information to open new circuits and that
an intro point was about to expire, a use-after-free is possible because of
the intro point object being both in the retry list and expiring list at the
same time.
The intro object would get freed after the circuit failed to open and then
access a second time when cleaned up from the expiring list.
Fixes#24313
Going from 4 hours to 24 hours in order to try reduce the efficiency of guard
discovery attacks.
Closes#23856
Signed-off-by: David Goulet <dgoulet@torproject.org>
We don't want to allow general signals to be sent, but there's no
problem sending a kill(0) to probe whether a process is there.
Fixes bug 24198; bugfix on 0.2.5.1-alpha when the seccomp2 sandbox
was introduced.
When we close a connection via connection_close_immediately, we kill
its events immediately. But if it had been blocked on bandwidth
read/write, we could try to re-add its (nonexistent) events later
from connection_bucket_refill -- if we got to that callback before
we swept the marked connections.
Fixes bug 24167. Fortunately, this hasn't been a crash bug since we
introduced connection_check_event in 0.2.9.10, and backported it.
This is a bugfix on commit 89d422914a, I believe, which
appeared in Tor 0.1.0.1-rc.
When we have fewer than 15 descriptors to fetch, we will delay the
fetch for a little while. That's fine, if we can go ahead and build
circuits... but if not, it's a poor choice indeed.
Fixes bug 23985; bugfix on 0.1.1.11-alpha.
In 0.3.0.3-alpha, when we made primary guard descriptors necessary
for circuit building, this situation got worse.
When calculating the fraction of nodes that have descriptors, and all
all nodes in the network have zero bandwidths, count the number of nodes
instead.
Fixes bug 23318; bugfix on 0.2.4.10-alpha.
Back in 0.2.4.3-alpha (e106812a77), when we switched from using
double to using uint64 for selecting by bandwidth, I got the math
wrong: I should have used llround(x), or (uint64_t)(x+0.5), but
instead I wrote llround(x+0.5). That means we would always round
up, rather than rounding to the closest integer
Fixes bug 23318; bugfix on 0.2.4.3-alpha.
Without this fix, changes from client to bridge don't trigger
transition_affects_workers(), so we would never have actually
initialized the cpuworkers.
Fixes bug 23693. Bugfix on 3bcdb26267 0.2.6.3-alpha, which
fixed bug 14901 in the general case, but not on the case where
public_server_mode() did not change.
When we added single_conn_free_bytes(), we cleared the outbuf on a
connection without setting outbuf_flushlen() to 0. This could cause
an assertion failure later on in flush_buf().
Fixes bug 23690; bugfix on 0.2.6.1-alpha.
This caused a BUG log when we noticed that the circuit had no
channel. The likeliest culprit for exposing that behavior is
d769cab3e5, where we made circuit_mark_for_close() NULL out
the n_chan and p_chan fields of the circuit.
Fixes bug 8185; bugfix on 0.2.5.4-alpha, I think.
Authority IPv6 addresses were originally added in 0.2.8.1-alpha.
This leaves 3/8 directory authorities with IPv6 addresses, but there
are also 52 fallback directory mirrors with IPv6 addresses.
Resolves 19760.
This change refactors find_dl_schedule() to only call dependent functions
as needed. In particular, directory_fetches_from_authorities() only needs
to be called on clients.
Stopping spurious directory_fetches_from_authorities() calls on every
download on public relays has the following impacts:
* fewer address resolution attempts, particularly those mentioned in 21789
* fewer descriptor rebuilds
* fewer log messages, particularly those limited in 20610
Fixes 23470 in 0.2.8.1-alpha.
The original bug was introduced in commit 35bbf2e as part of prop210.
OpenBSD doesn't like tricks where you use a too-wide sscanf argument
for a too-narrow array, even when you know the input string
statically. The fix here is just to use bigger buffers.
Fixes 15582; bugfix on a3dafd3f58 in 0.2.6.2-alpha.
Patch from Vort; fixes bug 23081; bugfix on fd992deeea in
0.2.1.16-rc when set_main_thread() was introduced.
See the changes file for a list of all the symptoms this bug has
been causing when running Tor as a Windows Service.
In the Linux kernel, the BUG() macro causes an instant panic. Our
BUG() macro is different, however: it generates a nonfatal assertion
failure, and is usable as an expression.
Additionally, this patch tells util_bug.h to make all assertion
failures into fatal conditions when we're building with a static
analysis tool, so that the analysis tool can look for instances
where they're reachable.
Fixes bug 23030.
Wow, it sure seems like some compilers can't implement isnan() and
friends in a way that pleases themselves!
Fixes bug 22915. Bug trigged by 0.2.8.1-alpha and later; caused by
clang 4.
Clang didn't like that we were passing uint64_t values to an API
that wanted uint32_t. GCC has either not cared, or has figured out
that the values in question were safe to cast to uint32_t.
Fixes bug22916; bugfix on 0.2.7.2-alpha.
When setting the maximum number of connections allowed by the OS,
always allow some extra file descriptors for other files.
Fixes bug 22797; bugfix on 0.2.0.10-alpha.
We just have to suppress these warnings: Mingw's math.h uses gcc's
__builtin_choose_expr() facility to declare isnan, isfinite, and
signbit. But as implemented in at least some versions of gcc,
__builtin_choose_expr() can generate type warnings even from
branches that are not taken.
Fixes bug 22801; bugfix on 0.2.8.1-alpha.
As of ac2f6b608a in 0.2.1.19-alpha,
Sebastian fixed bug 888 by marking descriptors as "impossible" by
digest if they got rejected during the
router_load_routers_from_string() phase. This fix stopped clients
and relays from downloading the same thing over and over.
But we never made the same change for descriptors rejected during
dirserv_add_{descriptor,extrainfo}. Instead, we tried to notice in
advance that we'd reject them with dirserv_would_reject().
This notice-in-advance check stopped working once we added
key-pinning and didn't make a corresponding key-pinning change to
dirserv_would_reject() [since a routerstatus_t doesn't include an
ed25519 key].
So as a fix, let's make the dirserv_add_*() functions mark digests
as undownloadable when they are rejected.
Fixes bug 22349; I am calling this a fix on 0.2.1.19-alpha, though
you could also argue for it being a fix on 0.2.7.2-alpha.
This mistake causes two possible bugs. I believe they are both
harmless IRL.
BUG 1: memory stomping
When we call the memset, we are overwriting two 0 bytes past the end
of packed_cell_t.body. But I think that's harmless in practice,
because the definition of packed_cell_t is:
// ...
typedef struct packed_cell_t {
TOR_SIMPLEQ_ENTRY(packed_cell_t) next;
char body[CELL_MAX_NETWORK_SIZE];
uint32_t inserted_time;
} packed_cell_t;
So we will overwrite either two bytes of inserted_time, or two bytes
of padding, depending on how the platform handles alignment.
If we're overwriting padding, that's safe.
If we are overwriting the inserted_time field, that's also safe: In
every case where we call cell_pack() from connection_or.c, we ignore
the inserted_time field. When we call cell_pack() from relay.c, we
don't set or use inserted_time until right after we have called
cell_pack(). SO I believe we're safe in that case too.
BUG 2: memory exposure
The original reason for this memset was to avoid the possibility of
accidentally leaking uninitialized ram to the network. Now
remember, if wide_circ_ids is false on a connection, we shouldn't
actually be sending more than 512 bytes of packed_cell_t.body, so
these two bytes can only leak to the network if there is another bug
somewhere else in the code that sends more data than is correct.
Fortunately, in relay.c, where we allocate packed_cell_t in
packed_cell_new() , we allocate it with tor_malloc_zero(), which
clears the RAM, right before we call cell_pack. So those
packed_cell_t.body bytes can't leak any information.
That leaves the two calls to cell_pack() in connection_or.c, which
use stack-alocated packed_cell_t instances.
In or_handshake_state_record_cell(), we pass the cell's contents to
crypto_digest_add_bytes(). When we do so, we get the number of
bytes to pass using the same setting of wide_circ_ids as we passed
to cell_pack(). So I believe that's safe.
In connection_or_write_cell_to_buf(), we also use the same setting
of wide_circ_ids in both calls. So I believe that's safe too.
I introduced this bug with 1c0e87f6d8
back in 0.2.4.11-alpha; it is bug 22737 and CID 1401591
On an hidden service rendezvous circuit, a BEGIN_DIR could be sent
(maliciously) which would trigger a tor_assert() because
connection_edge_process_relay_cell() thought that the circuit is an
or_circuit_t but is an origin circuit in reality.
Fixes#22494
Reported-by: Roger Dingledine <arma@torproject.org>
Signed-off-by: David Goulet <dgoulet@torproject.org>
