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>
When directory authorities reject a router descriptor due to keypinning,
free the router descriptor rather than leaking the memory.
Fixes bug 22370; bugfix on 0.2.7.2-alpha.
Directory authorities now reject relays running versions
0.2.9.1-alpha through 0.2.9.4-alpha, because those relays
suffer from bug 20499 and don't keep their consensus cache
up-to-date.
Resolves ticket 20509.
Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in
December 2016 (of which ~126 were still functional), with a list of
151 fallbacks (32 new, 119 existing, 58 removed) generated in May 2017.
Resolves ticket 21564.
Closes bug 22245; bugfix on 0.0.9rc1, when bandwidth accounting was
first introduced.
Found by Andrey Karpov and reported at https://www.viva64.com/en/b/0507/
One (HeapEnableTerminationOnCorruption) is on-by-default since win8;
the other (PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION) supposedly only
affects ATL, which (we think) we don't use. Still, these are good
hygiene. Closes ticket 21953.
The GETINFO extra-info/digest/<digest> broke in commit 568dc27a19 that
refactored the base16_decode() API to return the decoded length.
Unfortunately, that if() condition should have checked for the correct length
instead of an error which broke the command in tor-0.2.9.1-alpha.
Fixes#22034
Signed-off-by: David Goulet <dgoulet@torproject.org>
This change is the only one necessary to allow future versions of
the microdescriptor consensus to replace every 'published' date with
e.g. 2038-01-01 00:00:00; this will save 50-75% in compressed
microdescriptor diff size, which is quite significant.
This commit is a minimal change for 0.2.9; future series will
reduce the use of the 'published' date even more.
Implements part of ticket 21642; implements part of proposal 275.
strto* and _atoi64 accept +, -, and various whitespace before numeric
characters. And permitted whitespace is different between POSIX and Windows.
Fixes bug 21507 and part of 21508; bugfix on 0.0.8pre1.
This should be "impossible" without making a SHA1 collision, but
let's not keep the assumption that SHA1 collisions are super-hard.
This prevents another case related to 21278. There should be no
behavioral change unless -ftrapv is on.
I think this one probably can't underflow, since the input ranges
are small. But let's not tempt fate.
This patch also replaces the "cmp" functions here with just "eq"
functions, since nothing actually checked for anything besides 0 and
nonzero.
Related to 21278.
Fix for TROVE-2017-001 and bug 21278.
(Note: Instead of handling signed ints "correctly", we keep the old
behavior, except for the part where we would crash with -ftrapv.)
This reverts commit 5446cb8d3d.
The underlying revert was done in 0.2.6, since we aren't backporting
seccomp2 loosening fixes to 0.2.6. But the fix (for 17354) already
went out in 0.2.7.4-rc, so we shouldn't revert it in 0.2.7.
maint-0.2.7-redux is an attempt to try to re-create a plausible
maint-0.2.7 branch. I've started from the tor-0.2.7.6, and then I
merged maint-0.2.6 into the branch.
This has produced 2 conflicts: one related to the
rendcommon->rendcache move, and one to the authority refactoring.
The length of auth_data from an INTRODUCE2 cell is checked when the
auth_type is recognized (1 or 2), but not for any other non-zero
auth_type. Later, auth_data is assumed to have at least
REND_DESC_COOKIE_LEN bytes, leading to a client-triggered out of bounds
read.
Fixed by checking auth_len before comparing the descriptor cookie
against known clients.
Fixes#15823; bugfix on 0.2.1.6-alpha.
This disregards anything smaller than an IPv6 /64, and rejects ports that
are rejected on an IPv6 /16 or larger.
Adjust existing unit tests, and add more to cover exceptional cases.
No IPv4 behaviour changes.
Fixes bug 21357
This interim fix results in too many IPv6 rejections.
No behaviour change for IPv4 counts, except for overflow fixes that
would require 4 billion redundant 0.0.0.0/0 policy entries to trigger.
Part of 21357
When marking for close a circuit, the reason value, a integer, was assigned to
a uint16_t converting any negative reasons (internal) to the wrong value. On
the HS side, this was causing the client to flag introduction points to be
unreachable as the internal reason was wrongfully converted to a positive
16bit value leading to flag 2 out of 3 intro points to be unreachable.
Fixes#20307 and partially fixes#21056
Signed-off-by: David Goulet <dgoulet@torproject.org>
So far, the TTLs for both A and AAAA records were not initialised,
resulting in exit relays sending back the value 60 to Tor clients. This
also impacts exit relays' DNS cache -- the expiry time for all domains
is set to 60.
This fixes <https://bugs.torproject.org/19025>.
The server-side clipping now clamps to one of two values, both
for what to report, and how long to cache.
Additionally, we move some defines to dns.h, and give them better
names.
This helps protect against bugs where any part of a buf_t's memory
is passed to a function that expects a NUL-terminated input.
It also closes TROVE-2016-10-001 (aka bug 20384).
Replace the 81 remaining fallbacks of the 100 originally introduced
in Tor 0.2.8.3-alpha in March 2016, with a list of 177 fallbacks
(123 new, 54 existing, 27 removed) generated in December 2016.
Resolves ticket 20170.
In get_token(), we could read one byte past the end of the
region. This is only a big problem in the case where the region
itself is (a) potentially hostile, and (b) not explicitly
nul-terminated.
This patch fixes the underlying bug, and also makes sure that the
one remaining case of not-NUL-terminated potentially hostile data
gets NUL-terminated.
Fix for bug 21018, TROVE-2016-12-002, and CVE-2016-1254
The signed_descriptor_move() was not releasing memory inside the destination
object before overwriting it with the source object. This commit adds a reset
function that free that memory inside a signed descriptor object and zero it.
Closes#20715.
Signed-off-by: David Goulet <dgoulet@torproject.org>
When computing old Tor protocol line version in protover, we were looking at
0.2.7.5 twice instead of the specific case for 0.2.9.1-alpha.
Fixes#20810
Signed-off-by: David Goulet <dgoulet@torproject.org>
newconn->address is strdup'ed twice when new_type == CONN_TYPE_AP
and conn->socket_family == AF_UNIX. Whilst here, juggle code to
make sure newconn->port is assigned from an initialised value in
the above case.
Instead, refuse to start tor if any hidden service key has been used in
a different hidden service anonymity mode.
Fixes bug 20638; bugfix on 17178 in 0.2.9.3-alpha; reported by ahf.
The original single onion service poisoning code checked poisoning state
in options_validate, and poisoned in options_act. This was problematic,
because the global array of hidden services had not been populated in
options_validate (and there were ordrering issues with hidden service
directory creation).
This patch fixes this issue in rend_service_check_dir_and_add, which:
* creates the directory, or checks permissions on an existing directory, then
* checks the poisoning state of the directory, then
* poisons the directory.
When validating, only the permissions checks and the poisoning state checks
are perfomed (the directory is not modified).
(We only create HS directories if we are acting on the config.)
Log a BUG warning if the directories aren't present immediately before they
are used, then fail.
For relays that don't know their own address, avoid attempting
a local hostname resolve for each descriptor we download. Also cut
down on the number of "Success: chose address 'x.x.x.x'" log lines.
Fixes bugs 20423 and 20610; bugfix on 0.2.8.1-alpha.
Single onion services and Tor2web deliberately create long-term one-hop
circuits to their intro and rend points, respectively.
These log messages are intended to diagnose issue 8387, which relates to
circuits hanging around forever for no reason.
Fixes bug 20613; bugfix on 0.2.9.1-alpha. Reported by "pastly".
Because as Teor puts it: "[Resetting on 503] is exactly what we
don't want when relays are busy - imagine clients doing an automatic
reset every time they DoS a relay..."
Fixes bug 20593.
It's only safe to remove the failure limit (per 20536) if we are in
fact waiting a bit longer each time we try to download.
Fixes bug 20534; bugfix on 0.2.9.1-alpha.
If a consensus expires while we are waiting for certificates to download,
stop waiting for certificates.
If we stop waiting for certificates less than a minute after we started
downloading them, do not consider the certificate download failure a
separate failure.
Fixes bug 20533; bugfix on commit e0204f21 in 0.2.0.9-alpha.
Relays do not deliberately launch multiple attempts, so the impact of this
bug should be minimal. This fix also defends against bugs like #20499.
Bugfix on 0.2.8.1-alpha.
Fixes bug 19969; bugfix on b1d56fc58. We can fix this some more in
later Tors, but for now, this is probably the simplest fix possible.
This is a belt-and-suspenders fix, where the earlier fix ("Ask
event_base_loop to finish when we add a pending stream") aims to respond
to new streams as soon as they arrive, and this one aims to make sure
that we definitely respond to all of the streams.
ome policies are default-reject, some default-accept. But
policy_is_reject_star() assumed they were all default_reject. Fix
that!
Also, document that policy_is_reject_star() treats a NULL policy as
empty. This allows us to simplify the checks in
parse_reachable_addresses() by quite a bit.
Fxes bug 20306; bugfix on 0.2.8.2-alpha.
(Also, refactor the code to create a hidden service directory into a
separate funcion, so we don't have to duplicate it.)
Fixes bug 20484; bugfix on 0.2.9.3-alpha.
This simplifies the function: if we have an ntor key, use ntor/EXTEND2,
otherwise, use TAP/EXTEND.
Bugfix on commit 10aa913 from 19163 in 0.2.9.3-alpha.
The tor_fragile_assert() bug has existed here since c8a5e2d588
in tor-0.2.1.7-alpha forever, but tor_fragile_assert() was mostly a
no-op until 0.2.9.1-alpha.
Fixes bug 19869.
This helps protect against bugs where any part of a buf_t's memory
is passed to a function that expects a NUL-terminated input.
It also closes TROVE-2016-10-001 (aka bug 20384).
This commit adds or improves the module-level documenation for:
buffers.c circuitstats.c command.c connection_edge.c control.c
cpuworker.c crypto_curve25519.c crypto_curve25519.h
crypto_ed25519.c crypto_format.c dircollate.c dirserv.c dns.c
dns_structs.h fp_pair.c geoip.c hibernate.c keypin.c ntmain.c
onion.c onion_fast.c onion_ntor.c onion_tap.c periodic.c
protover.c protover.h reasons.c rephist.c replaycache.c
routerlist.c routerparse.c routerset.c statefile.c status.c
tor_main.c workqueue.c
In particular, I've tried to explain (for each documented module)
what each module does, what's in it, what the big idea is, why it
belongs in Tor, and who calls it. In a few cases, I've added TODO
notes about refactoring opportunities.
I've also renamed an argument, and fixed a few DOCDOC comments.
(I've done this instead of changing the semantics of
router_compare_to_my_exit_policy, because dns.c uses
router_compare_to_my_exit_policy too, in a slightly weird way.)
Some compilers apparently noticed that p2len was allowed to be equal
to msg, and so maybe we would be doing memset(prompt2, ' ', 0), and
decided that we probably meant to do memset(prompt2, 0, 0x20);
instead.
Stupid compilers, doing optimization before this kind of warning!
My fix is to just fill the entire prompt2 buffer with spaces,
because it's harmless.
Bugfix on e59f0d4cb9, not in any released Tor.
Previously, we would reject even rendezvous connections to IPv6
addresses when IPv6Exit was false. But that doesn't make sense; we
don't count that as "exit"ing. I've corrected the logic and tried
to make it a lottle more clear.
Fixes bug 18357; this code has been wrong since 9016d9e829 in
0.2.4.7-alpha.
We removed that feature in 0.2.4.2-alpha, but some comments seem to
have lingered.
I didn't add a changes/ file since this is just internal code cleanup.
The client addr is essentially meaningless in this context (yes, it is
possible to explicitly `bind()` AF_LOCAL client side sockets to a path,
but no one does it, and there are better ways to grant that sort of
feature if people want it like using `SO_PASSCRED`).
As before, we check server protocols whenever server_mode(options)
is true and we check client protocols whenever server_mode(options)
is false.
Additionally, we now _also_ check client protocols whenever any
client port is set.
(Technically, we could just remove extend2 cell checking entirely,
since all Tor versions on our network are required to have it, but
let's keep this around as an example of How To Do It.)
(Despite the increased size of the consensus, this should have
approximately zero effect on the compressed consensus size, since
the "proto" line should be completely implied by the "v" line.)
