Currently test the only available function which is hs_dos_can_send_intro2()
within the HS anti-DoS subsystem.
Closes#15516
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit add the hs_dos.{c|h} file that has the purpose of having the
anti-DoS code for onion services.
At this commit, it only has one which is a function that decides if an
INTRODUCE2 can be sent on the given introduction service circuit (S<->IP)
using a simple token bucket.
The rate per second is 25 and allowed burst to 200.
Basic defenses on #15516.
Signed-off-by: David Goulet <dgoulet@torproject.org>
A .may_includes file can be "advisory", which means that some
violations of the rules are expected. We will track these
violations with practracker, not as automatic errors.
Padding circuits were regular cells that got closed before their padding
machine could finish. This means that they can still receive regular cells from
their past life, but they have no way or reason to answer them anymore. Hence
let's ignore them before they even get to the proper subsystems.
Padding circuits were regular cells that got closed before their padding
machine could finish. This means that they can still receive regular cells from
their past life, but they have no way or reason to answer them anymore. Hence
let's ignore them before they even get to the proper subsystems.
This C file will eventually belong in lib/confmgt, so it needs to
have only low-level dependencies. Now that it no longers needs
routerset.c, we can adjust its includes accordingly.
I'm not moving the file yet, since it would make fixup commits on
earlier branches here really hard to do.
Now that we have a reasonable implementation for overriding the
default options for TestingTorNetwork, we don't need to modify
config_var_t structs any more. And therefore, we can have constant
format options, like reasonable people.
It's important to make sure that we don't change a config_mgr_t
after we start using it to make objects, or we could get into
inconsistent states. This feature is the start of a safety
mechanism to prevent this problem.
Previously, when TestingTorNetwork was set, we would manually adjust
the initvalue members of a bunch of other config_var_t, and then
re-run the early parts or parsing the options.
Now we treat the initvalue fields as immutable, but instead assign
to them in options_init(), as early as possible. Rather than
re-running the early parts of options, we just re-call the
options_init_from_string() function.
This patch de-kludges some of our code pretty handily. I think it
could later handle authorities and fallbacks, but for now I think we
should leave those alone.
Iterating over this array was once a good idea, but now that we are
going to have a separate structure for each submodule's
configuration variables, we should indirect through the config_mgr_t
object.
The eventual design here will be that multiple config_format_t
objects get registered with a single config_mgr_t. That
config_mgr_t manages a "top-level" object, which has a pointer to
the other objects.
I had earlier thought of a different design, where there would be no
top-level object, and config_mgr_t would deal with a container
instead. But this would require a bunch of invasive refactoring
that I don't think we should do just yet.
Remember that our goal in the present refactoring is to allow each
subsystem to declare its own configuration structure and
variables. To do this, each module will get its own
config_format_t, and so we'll want a different structure that wraps
several config_format_t objects. This is a "config_mgr_t".
This shouldn't be possible while Tor is running, but the tests can
hit this code. Rather than force the tests to add a dummy channel
object, let's just tolerate their incompletely built circuits.
Make origin-side messages about padding negotiation failure into
LOG_PROTOCOL_WARN.
I'm not sure I like this either.. But the negotiation refusal case might
happen naturally due to consensus drift, and is functionally no different than
a corrupted cell.
There is other code that uses this value, and some of it is
apparently reachable from inside router_dir_info_changed(), which
routerlist_free() apparently calls. (ouch!) This is a minimal fix
to try to resolve the issue without causing other problems.
Fixes bug 31003. I'm calling this a bugfix on 0.1.2.2-alpha, where
the call to router_dir_info_changed() was added to routerlist_free().
Overflowing a signed integer in C is an undefined behaviour.
It is possible to trigger this undefined behaviour in tor_asprintf on
Windows or systems lacking vasprintf.
On these systems, eiter _vscprintf or vsnprintf is called to retrieve
the required amount of bytes to hold the string. These functions can
return INT_MAX. The easiest way to recreate this is the use of a
specially crafted configuration file, e.g. containing the line:
FirewallPorts AAAAA<in total 2147483610 As>
This line triggers the needed tor_asprintf call which eventually
leads to an INT_MAX return value from _vscprintf or vsnprintf.
The needed byte for \0 is added to the result, triggering the
overflow and therefore the undefined behaviour.
Casting the value to size_t before addition fixes the behaviour.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
When we added LD_MESG, we created a conflict with the LD_NO_MOCK
flag. We now need 64 bits for log domains in order to fix this
issue.
Fixes bug 31080; bugfix on 0.4.1.1-alpha.
The function make_intro_from_plaintext() in test_introduce.c would
leak memory if we ever hit a failure from our underlying crypto
functions. This kind of failure should be impossible, but it's best
to be safe here.
Bugfix on 0.2.4.1-alpha.
Coverity is worried that we check "service" at the end of these test
functions, since it doesn't see any way to reach the cleanup code
without having first dereferenced the variable.
Removing the check would be unwise in this case: instead we add a
tt_assert check before using "service" so that coverity thinks that
the check is doing something useful.
Bugfix on 0.3.2.1-alpha.
Coverity can't see that it is not in fact going to read
uninitialized memory here, so we initialize these values
unconditionally.
Bugfix on 0.4.0.1-alpha.
Coverity has had trouble figuring out our csiphash implementation,
and has given spurious warnings about its behavior.
This patch changes the csiphash implementation when coverity is in
use, so that coverity can figure out that we are not about to read
beyond the provided input.
Closes ticket 31025.
Coverity doesn't understand that if begin_cell_parse() returns 0 and
sets is_begindir to 0, its address field will always be set.
Fixes bug 30126; bugfix on 0.2.4.7-alpha; Fixes CID 1447296.
Update the fallback directory mirrors by merging the current list with:
fallback_dirs_2019-06-28-08-58-39_AU_f0437a39ddbc8459.inc
Part of 28795, see that ticket for logs.
Update the fallback directory mirrors by replacing the old list with:
fallback_dirs_2019-06-25-11-49-10_AU_a37adb956fbb5cd2.inc
Part of 28795, see that ticket for logs.
And that it does something sensible with host and host:port.
Also reorder the tests into valid, invalid, and ambiguous.
And add some missing cases.
Note: tor_addr_port_lookup() handles ip, ip:port, host, and host:port.
Tests for 30721.
When parsing addreses via Tor's internal address:port parsing and
DNS lookup APIs, require IPv6 addresses with ports to have square
brackets.
But allow IPv6 addresses without ports, whether or not they have
square brackets.
Fixes bug 30721; bugfix on 0.2.1.5-alpha.
When parsing addreses via Tor's internal DNS lookup API:
* reject IPv4 addresses in square brackets (with or without a port),
* accept IPv6 addresses in square brackets (with or without a port), and
* accept IPv6 addresses without square brackets, as long as they have no port.
This change completes the work started in 23082, making address parsing
consistent between tor's internal DNS lookup and address parsing APIs.
Fixes bug 30721; bugfix on 0.2.1.5-alpha.
"unsettable" is a property of types. LINELIST_V and OBSOLETE are
unsettable, meaning that they cannot be set by name.
"contained" is a property of types. I'm hoping to find a better
name here. LINELIST_S is "contained" because it always appears
within a LINELIST_V, and as such doesn't need to be dumped ore
copied independently.
"cumulative" is a property of types. Cumulative types can appear
more than once in a torrc without causing a warning, because they
add to each other rather than replacing each other.
"obsolete" is a property of variables.
"marking fragile" is now a command that struct members can accept.
With these changes, confparse and config no longer ever need to
mention CONFIG_TYPE_XYZ values by name.
Fix add_onion_helper_clientauth() and add_onion_helper_keyarg() to
explicitly call the appropriate control reply abstractions instead of
allocating a string to pass to their callers.
Part of ticket 30889.
Right now, this has been done at a high level by confparse.c, but it
makes more sense to lower it.
This API is radically un-typesafe as it stands; we'll be wrapping it
in a safer API as we do #30914 and lower the struct manipulation
code as well.
Closes ticket 30864.
If the signature data was removed, but the keyword was kept, this could
result in an unparseable extra info file.
Fixes bug 30958; bugfix on 0.2.7.2-alpha.
Always publish bridge pluggable transport information in the extra info
descriptor, even if ExtraInfoStatistics is 0. This information is
needed by BridgeDB.
Fixes bug 30956; bugfix on 0.4.1.1-alpha.
This will effectively also deny any bridge to be used as a single hop to the
introduction point since bridge do not authenticate like clients.
Fixes#24963
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we consider all circuits in "waiting for guard" state to be promoted to
an "open" state, we were considering all circuits, even the one marked for
close.
This ultiamtely triggers a "circuit_has_opened()" called on the circuit that
is marked for close which then leads to possible undesirable behaviors within
a subsystem.
For instance, the HS subsystem would be unable to find the authentication key
of the introduction point circuit leading to a BUG() warning and a duplicate
mark for close on the circuit.
This commit also adds a unit test to make sure we never select marked for
close circuits when upgrading its guard state from waiting for guard to open.
Fixes#30871
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we consider all circuits in "waiting for guard" state to be promoted to
an "open" state, we were considering all circuits, even the one marked for
close.
This ultiamtely triggers a "circuit_has_opened()" called on the circuit that
is marked for close which then leads to possible undesirable behaviors within
a subsystem.
For instance, the HS subsystem would be unable to find the authentication key
of the introduction point circuit leading to a BUG() warning and a duplicate
mark for close on the circuit.
This commit also adds a unit test to make sure we never select marked for
close circuits when upgrading its guard state from waiting for guard to open.
Fixes#30871
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we consider all circuits in "waiting for guard" state to be promoted to
an "open" state, we were considering all circuits, even the one marked for
close.
This ultiamtely triggers a "circuit_has_opened()" called on the circuit that
is marked for close which then leads to possible undesirable behaviors within
a subsystem.
For instance, the HS subsystem would be unable to find the authentication key
of the introduction point circuit leading to a BUG() warning and a duplicate
mark for close on the circuit.
This commit also adds a unit test to make sure we never select marked for
close circuits when upgrading its guard state from waiting for guard to open.
Fixes#30871
Signed-off-by: David Goulet <dgoulet@torproject.org>
Note that the event base object is _not_ created from the initialize
function, since it is configuration-dependent. This will wait until
configuration is integrated into subsystems.
Closes ticket 30806.
This is to avoid having two sendme.{c|h} in the repository since the subsystem
is implemented in src/core/or/sendme.{c|h}.
Fixes#30769
Signed-off-by: David Goulet <dgoulet@torproject.org>
Skip test_rebind when the TOR_SKIP_TEST_REBIND environmental variable
is set.
Skip test_rebind on macOS in Travis builds, because it is unreliable
on macOS on Travis.
Fixes bug 30713; bugfix on 0.3.5.1-alpha.
Adds ROUTER_AUTHDIR_BUG_ANNOTATIONS to was_router_added_t.
The out-of-order numbering is deliberate: it will be fixed by later commits
for 16564.
Fixes bug 30780; bugfix on 0.2.0.8-alpha.
Leave the other rend and hs_ident data around until circuit free, since code
may still try to inspect it after marking the circuit for close. The
circuitmap is the important thing to clean up, since repurposed
intropoints must be removed from this map to ensure validity.
Make origin-side messages about padding negotiation failure into
LOG_PROTOCOL_WARN.
I'm not sure I like this either.. But the negotiation refusal case might
happen naturally due to consensus drift, and is functionally no different than
a corrupted cell.
Leave the other rend and hs_ident data around until circuit free, since code
may still try to inspect it after marking the circuit for close. The
circuitmap is the important thing to clean up, since repurposed
intropoints must be removed from this map to ensure validity.
If "Log debug ..." is not set, the decrement never happens. This lead to the
package/deliver window to be out of sync at the stream level and thus breaking
the connection after 50+ cells.
Fixes#30628
Signed-off-by: David Goulet <dgoulet@torproject.org>
When this function was implemented, it counted all the entry guards
in the bridge set. But this included previously configured bridges,
as well as currently configured ones! Instead, only count the
_filtered_ bridges (ones that are configured and possibly reachable)
as maybe usable.
Fixes bug 29875; bugfix on 0.3.0.1-alpha.
This is necessary since shutting down libevent frees some pointer
that the subsystems want to free themselves. A longer term solution
will be to turn the evloop module into a subsystem itself, but for
now it is best to do the minimal fix.
Fixes bug 30629; bugfix on 0.4.1.1-alpha.
Previously, we were looking at our global settings to see what kind
of proxy we had. But doing this would sometimes give us the wrong
results when we had ClientTransportPlugin configured but we weren't
using it for a particular connection. In several places in the
code, we had added checks to see if we were _really_ using a PT or
whether we were using a socks proxy, but we had forgotten to do so
in at least once case. Instead, since every time we call this
function we are asking about a single connection, it is probably
best just to make this function connection-specific.
Fixes bug 29670; bugfix on 0.2.6.2-alpha.
When we repurpose a hidden service circuit, we need to clean up from the HS
circuit map and any HS related data structured contained in the circuit.
This commit adds an helper function that does it when repurposing a hidden
service circuit.
Fixes#29034
Signed-off-by: David Goulet <dgoulet@torproject.org>
If tor is compiled on a system with neither vasprintf nor _vscprintf,
the fallback implementation exposes a logic flaw which prevents
proper usage of strings longer than 127 characters:
* tor_vsnprintf returns -1 if supplied buffer is not large enough,
but tor_vasprintf uses this function to retrieve required length
* the result of tor_vsnprintf is not properly checked for negative
return values
Both aspects together could in theory lead to exposure of uninitialized
stack memory in the resulting string. This requires an invalid format
string or data that exceeds integer limitations.
Fortunately tor is not even able to run with this implementation because
it runs into asserts early on during startup. Also the unit tests fail
during a "make check" run.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
[backported to 0.2.9 by nickm]
Fixes assertion failure in tests on NetBSD:
slow/prob_distr/stochastic_log_logistic: [forking] May 25 03:56:58.091 [err] tor_assertion_failed_(): Bug: src/lib/crypt_ops/crypto_rand_fast.c:184: crypto_fast_rng_new_from_seed: Assertion inherit != INHERIT_RES_KEEP failed; aborting. (on Tor 0.4.1.1-alpha-dev 29955f13e5)
May 25 03:56:58.091 [err] Bug: Assertion inherit != INHERIT_RES_KEEP failed in crypto_fast_rng_new_from_seed at src/lib/crypt_ops/crypto_rand_fast.c:184: . (Stack trace not available) (on Tor 0.4.1.1-alpha-dev 29955f13e5)
[Lost connection!]
Proposal 289 prevents SENDME-flooding by requiring the other side to
authenticate the data it has received. But this data won't actually
be random if they are downloading a known resource. "No problem",
we said, "let's fell the empty parts of our cells with some
randomness!" and we did that in #26871.
Unfortunately, if the relay data payloads are all completely full,
there won't be any empty parts for us to randomize.
Therefore, we now pick random "randomness windows" between
CIRCWINDOW_INCREMENT/2 and CIRCWINDOW_INCREMENT. We remember whether we have
sent a cell containing at least 16 bytes of randomness in that window. If we
haven't, then when the window is exhausted, we send one. (This window approach
is designed to lower the number of rng checks we have to do. The number 16 is
pulled out of a hat to change the attacker's guessing difficulty to
"impossible".)
Implements 28646.
Because it invokes the Tor mainloop, it does unpredictable things to
test coverage of a lot of code that it doesn't actually test at
all. (It is more an integration test than anything else.)
The ordinary definitions of timeradd() and timersub() contain a
branch. However, in coverage builds, this means that we get spurious
complaints about partially covered basic blocks, in a way that makes
our coverage determinism harder to check.
Ordinarily we skip calling log_fn(LOG_DEBUG,...) if debug logging is
completely disabled. However, in coverage builds, this means that
we get spurious complaints about partially covered basic blocks, in
a way that makes our coverage determinism harder to check.
Two non fatal asserts are added in this commit. First one is to see if the
SENDME digest list kept on the circuit for validation ever grows bigger than
the maximum number of expected SENDME on a circuit (currently 10).
The second one is to know if we ever send more than one SENDME at a time on a
circuit. In theory, we shouldn't but if we ever do, the v1 implementation
wouldn't work because we only keep one single cell digest (the previous cell
to the SENDME) on the circuit/cpath. Thus, sending two SENDME consecutively
will lead to a mismatch on the other side because the same cell digest would
be use and thus the circuit would collapse.
Finally, add an extra debug log in case we emit a v0 which also includes the
consensus emit version in that case.
Part of #30428
Signed-off-by: David Goulet <dgoulet@torproject.org>
We must not accumulate digests on the circuit if the other end point is using
another SENDME version that is not using those digests like v0.
This commit makes it that we always pop the digest regardless of the version.
Part of #30428
Signed-off-by: David Goulet <dgoulet@torproject.org>
Commit 4ef8470fa5480d3b was actually reverted before because in the end we
needed to do this minus 1 check on the window.
This commit clarifies that in the code, takes the useful comment changes from
4ef8470fa5480d3b and makes sendme_circuit_cell_is_next() private since it
behaves in a very specific way that one external caller might expect.
Part of #30428.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Turns out that we were only recording the "b_digest" but to have
bidirectionnal authenticated SENDMEs, we need to use the "f_digest" in the
forward cell situation.
Because of the cpath refactoring, this commit plays with the crypt_path_ and
relay_crypto_t API a little bit in order to respect the abstractions.
Previously, we would record the cell digest as the SENDME digest in the
decrypt cell function but to avoid code duplication (both directions needs to
record), we now do that right after iff the cell is recognized (at the edge).
It is now done in circuit_receive_relay_cell() instead.
We now also record the cell digest as the SENDME digest in both relay cell
encryption functions since they are split depending on the direction.
relay_encrypt_cell_outbound() and relay_encrypt_cell_inbound() need to
consider recording the cell digest depending on their direction (f vs b
digest).
Fixes#30428
Signed-off-by: David Goulet <dgoulet@torproject.org>
There was a missing cell version check against our max supported version. In
other words, we do not fallback to v0 anymore in case we do know the SENDME
version.
We can either handle it or not, never fallback to the unauthenticated version
in order to avoid gaming the authenticated logic.
Add a unit tests making sure we properly test that and also test that we can
always handle the default emit and accepted versions.
Fixes#30428
Signed-off-by: David Goulet <dgoulet@torproject.org>
The validation of the SENDME cell is now done as the very first thing when
receiving it for both client and exit. On failure to validate, the circuit is
closed as detailed in the specification.
Part of #30428
Signed-off-by: David Goulet <dgoulet@torproject.org>
It turns out that only the exit side is validating the authenticated SENDME v1
logic and never the client side. Which means that if a client ever uploaded
data towards an exit, the authenticated SENDME logic wouldn't apply.
For this to work, we have to record the cell digest client side as well which
introduced a new function that supports both type of edges.
This also removes a test that is not valid anymore which was that we didn't
allow cell recording on an origin circuit (client).
Part of #30428
Signed-off-by: David Goulet <dgoulet@torproject.org>
We want to support parsing a cell with unknown status code so we are forward
compatible.
Part of #30454
Signed-off-by: David Goulet <dgoulet@torproject.org>
Like the previous commit about the INTRODUCE_ACK status code, change all auth
key type to use the one defined in the trunnel file.
Standardize the use of these auth type to a common ABI.
Part of #30454
Signed-off-by: David Goulet <dgoulet@torproject.org>
This enum was the exact same as hs_intro_ack_status_t that was removed at the
previous commit. It was used client side when parsing the INTRODUCE_ACK cell.
Now, the entire code dealing with the INTRODUCE_ACK cell (both sending and
receiving) have been modified to all use the same ABI defined in the trunnel
introduce1 file.
Finally, the client will default to the normal behavior when receiving an
unknown NACK status code which is to note down that we've failed and re-extend
to the next intro point. This way, unknown status code won't trigger a
different behavior client side.
Part of #30454.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Remove the hs_intro_ack_status_t enum and move the value into trunnel. Only
use these values from now on in the intro point code.
Interestingly enough, the client side also re-define these values in hs_cell.h
with the hs_cell_introd_ack_status_t enum. Next commit will fix that and force
to use the trunnel ABI.
Part of #30454
Signed-off-by: David Goulet <dgoulet@torproject.org>
Previously we purged it in 1-hour increments -- but one-hour is the
maximum TTL for the cache! Now we do it in 25%-TTL increments.
Fixes bug 29617; bugfix on 0.3.5.1-alpha.
The client side had garbage histograms and deadcode here, too. That code has
been removed.
The tests have also been updated to properly test the intro circ by sending
padding from the relay side to the client, and verifying that both shut down
when padding was up. (The tests previously erroneously tested only the client
side of intro circs, which actually were supposed to be doing nothing).
This just moves the state transition directives into the proper client/relay
side functions. It also allows us to remove some dead-code from the client
side (since the client doesn't send padding).
This is the first half of implementing proposal 301. The
RecommendedPackages torrc option is marked as obsolete and
the test cases for the option removed. Additionally, the code relating
to generating and formatting package lines in votes is removed.
These lines may still appear in votes from other directory authorities
running earlier versions of the code and so consensuses may still
contain package lines. A new consensus method will be needed to stop
including package lines in consensuses.
Fixes: #28465
- Add some more useful logs for future debugging.
- Stop usage of circpad_state_to_string(). It's innacurate.
- Reduce severity and fix up log domain of some logging messages.
To ease debugging of miscount issues, attach vanguards with --loglevel DEBUG
and obtain control port logs (or use any other control port CIRC and
CIRC_MINOR event logging mechanism).
If circuit padding wants to keep a circuit open and pathbias used to ignore
it, pathbias should continue to ignore it.
This may catch other purpose-change related miscounts (such as timeout
measurement, cannibalization, onion service circuit transitions, and
vanguards).
When a circuit is marked for close, check to see if any of our padding
machines want to take ownership of it and continue padding until the machine
hits the END state.
For safety, we also ensure that machines that do not terminate are still
closed as follows: Because padding machine timers are UINT32_MAX in size, if
some sort of network event doesn't happen on a padding-only circuit within
that time, we can conclude it is deadlocked and allow
circuit_expire_old_circuits_clientside() to close it.
If too much network activity happens, then per-machine padding limits can be
used to cease padding, which will cause network cell events to cease, on the
circuit, which will cause circpad to abandon the circuit as per the above time
limit.
We need to check here because otherwise we can try to schedule padding with no
tokens left upon the receipt of a padding event when our bins just became
empty.
Our other tests tested state lengths against padding packets, and token counts
against non-padding packets. This test checks state lengths against
non-padding packets (and also padding packets too), and checks token counts
against padding packets (and also non-padding packets too).
The next three commits are needed to make this test pass (it found 3 bugs).
Yay?
Since the reproducible RNG dumps its own seed, we don't need to do
it for it. Since tinytest can tell us if the test failed, we don't
need our own test_failed booleans.
This commit moves code that updates the state length and padding limit counts
out from the callback to its own function, for clarity.
It does not change functionality.
This commit moves the padding state limit checks and the padding rate limit
checks out of the token removal codepath, and causes all three functions to
get called from a single circpad_machine_count_nonpadding_sent() function.
It does not change functionality.
The code flow in theory can end up with a layer_hint to be NULL but in
practice it should never happen because with an origin circuit, we must have
the layer_hint.
Just in case, BUG() on it if we ever end up in this situation and recover by
closing the circuit.
Fixes#30467.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Fortunately, in 0.3.5.1-alpha we improved logging for various
failure cases involved with onion service client auth.
Unfortunately, for this one, we freed the file right before logging
its name.
Fortunately, tor_free() sets its pointer to NULL, so we didn't have
a use-after-free bug.
Unfortunately, passing NULL to %s is not defined.
Fortunately, GCC 9.1.1 caught the issue!
Unfortunately, nobody has actually tried building Tor with GCC 9.1.1
before. Or if they had, they didn't report the warning.
Fixes bug 30475; bugfix on 0.3.5.1-alpha.
The INTRODUCE1 trunnel definition file doesn't support that value so it can
not be used else it leads to an assert on the intro point side if ever tried.
Fortunately, it was impossible to reach that code path.
Part of #30454
Signed-off-by: David Goulet <dgoulet@torproject.org>
See proposal 289 section 4.3 for more details.
It describes the flow control protocol at the circuit and stream level. If
there is no FlowCtrl protocol version, tor supports the unauthenticated flow
control features from its supported Relay protocols.
At this commit, relay will start advertising FlowCtrl=1 meaning they support
authenticated SENDMEs v1.
Closes#30363
Signed-off-by: David Goulet <dgoulet@torproject.org>
- Move test-only cpath_get_n_hops() to crypt_path.c.
- Move onion_next_hop_in_cpath() and rename to cpath_get_next_non_open_hop().
The latter function was directly accessing cpath->state, and it's a first step
at hiding ->state.
Some of these functions are now public and cpath-specific so their name should
signify the fact they are part of the cpath module:
assert_cpath_layer_ok -> cpath_assert_layer_ok
assert_cpath_ok -> cpath_assert_ok
onion_append_hop -> cpath_append_hop
circuit_init_cpath_crypto -> cpath_init_circuit_crypto
circuit_free_cpath_node -> cpath_free
onion_append_to_cpath -> cpath_extend_linked_list
Now that we are using a constructor we should be more careful that we are
always using the constructor to initialize crypt_path_t, so make sure that
->private is initialized.
We are using an opaque pointer so the structure needs to be allocated on the
heap. This means we now need a constructor for crypt_path_t.
Also modify all places initializing a crypt_path_t to use the constructor.
For various reasons, this was a nontrivial movement. There are
several places in the code where we do something like "update the
flags on this routerstatus or node if we're an authority", and at
least one where we pretended to be an authority when we weren't.
I don't believe any of these represent a real timing vulnerability
(remote timing against memcmp() on a modern CPU is not easy), but
these are the ones where I believe we should be more careful.
For memeq and friends, "tor_" indicates constant-time and "fast_"
indicates optimized. I'm fine with leaving the constant-time
"safe_mem_is_zero" with its current name, but the "tor_" prefix on
the current optimized version is misleading.
Also, make the tor_digest*_is_zero() uniformly constant-time, and
add a fast_digest*_is_zero() version to use as needed.
A later commit in this branch will fix all the users of
tor_mem_is_zero().
Closes ticket 30309.
Manually fix up some reply-generating code that the Coccinelle scripts
won't match. Some more complicated ones remain -- these are mostly
ones that accumulate data to send, and then call connection_buf_add()
or connection_write_str_to_buf() directly.
Create a set of abstractions for controller commands and events to
output replies to the control channel. The control protocol has a
relatively consistent SMTP-like structure, so it's helpful when code
that implements control commands and events doesn't explicitly format
everything on its own.
Split the core reply formatting code out of control_fmt.c into
control_proto.c. The remaining code in control_format.c deals with
specific subsystems and will eventually move to join those subsystems.
When we tell the periodic event manager about an event, we are
"registering" that event. The event sits around without being
usable, however, until we "connect" the event to libevent. In the
end, we "disconnect" the event and remove its libevent parts.
Previously, we called these operations "add", "setup", and
"destroy", which led to confusion.
We need a little refactoring for this to work, since the
initialization code for the periodic events assumes that libevent is
already initialized, which it can't be until it's configured.
This change, combined with the previous ones, lets other subsystems
declare their own periodic events, without mainloop.c having to know
about them. Implements ticket 30293.
Because this function is poking within the relay_crypto_t object, move the
function to the module so we can keep it opaque as much as possible.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
We add random padding to every cell if there is room. This commit not only
fixes how we compute that random padding length/offset but also improves its
safety with helper functions and a unit test.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
We'll use it this in order to know when to hash the cell for the SENDME
instead of doing it at every cell.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
When adding random to a cell, skip the first 4 bytes and leave them zeroed. It
has been very useful in the past for us to keep bytes like this.
Some code trickery was added to make sure we have enough room for this 4 bytes
offset when adding random.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
The digest object is as large as the entire internal digest object's state,
which is often much larger than the actual set of bytes you're transmitting.
This commit makes it that we keep the digest itself which is 20 bytes.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
No behavior change but code had to be refactored a bit. Also, the tor_memcmp()
was changed to tor_memneq().
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
The circuit and stream level functions that update the package window have
been renamed to have a "_note_" in them to make their purpose more clear.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
No behavior change. Only moving code and fixing part of it in order to use the
parameters passed as pointers.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
To achieve such, this commit also changes the trunnel declaration to use a
union instead of a seperate object for the v1 data.
A constant is added for the digest length so we can use it within the SENDME
code giving us a single reference.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
In order to do so, depending on where the cell is going, we'll keep the last
cell digest that is either received inbound or sent outbound.
Then it can be used for validation.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
Now that we keep the last seen cell digests on the Exit side on the circuit
object, use that to match the SENDME v1 transforming this whole process into a
real authenticated SENDME mechanism.
Part of #26841
Signed-off-by: David Goulet <dgoulet@torproject.org>
This makes tor remember the last seen digest of a cell if that cell is the
last one before a SENDME on the Exit side.
Closes#26839
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit makes tor able to parse and handle a SENDME version 1. It will
look at the consensus parameter "sendme_accept_min_version" to know what is
the minimum version it should look at.
IMPORTANT: At this commit, the validation of the cell is not fully
implemented. For this, we need #26839 to be completed that is to match the
SENDME digest with the last cell digest.
Closes#26841
Signed-off-by: David Goulet <dgoulet@torproject.org>
This code will obey the consensus parameter "sendme_emit_min_version" to know
which SENDME version it should send. For now, the default is 0 and the
parameter is not yet used in the consensus.
This commit adds the support to send version 1 SENDMEs but aren't sent on the
wire at this commit.
Closes#26840
Signed-off-by: David Goulet <dgoulet@torproject.org>
In order to be able to deploy the authenticated SENDMEs, these two consensus
parameters are needed to control the minimum version that we can emit and
accept.
See section 4 in prop289 for more details.
Note that at this commit, the functions that return the values aren't used so
compilation fails if warnings are set to errors.
Closes#26842
Signed-off-by: David Goulet <dgoulet@torproject.org>
Previously, we would only close the stream when our deliver window was
negative at the circuit-level but _not_ at the stream-level when receiving a
DATA cell.
This commit adds an helper function connection_edge_end_close() which
sends an END and then mark the stream for close for a given reason.
That function is now used both in case the deliver window goes below zero for
both circuit and stream level.
Part of #26840
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we are about to send a DATA cell, we have to decrement the package window
for both the circuit and stream level.
This commit adds helper functions to handle the package window decrement.
Part of #26288
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we get a relay DATA cell delivered, we have to decrement the deliver
window on both the circuit and stream level.
This commit adds helper functions to handle the deliver window decrement.
Part of #26840
Signed-off-by: David Goulet <dgoulet@torproject.org>
This is a bit of a complicated commit. It moves code but also refactors part
of it. No behavior change, the idea is to split things up so we can better
handle and understand how SENDME cells are processed where ultimately it will
be easier to handle authenticated SENDMEs (prop289) using the intermediate
functions added in this commit.
The entry point for the cell arriving at the edge (Client or Exit), is
connection_edge_process_relay_cell() for which we look if it is a circuit or
stream level SENDME. This commit refactors that part where two new functions
are introduced to process each of the SENDME types.
The sendme_process_circuit_level() has basically two code paths. If we are a
Client (the circuit is origin) or we are an Exit. Depending on which, the
package window is updated accordingly. Then finally, we resume the reading on
every edge streams on the circuit.
The sendme_process_stream_level() applies on the edge connection which will
update the package window if needed and then will try to empty the inbuf if
need be because we can now deliver more cells.
Again, no behavior change but in order to split that code properly into their
own functions and outside the relay.c file, code modification was needed.
Part of #26840.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Take apart the SENDME cell specific code and put it in sendme.{c|h}. This is
part of prop289 that implements authenticated SENDMEs.
Creating those new files allow for the already huge relay.c to not grow in LOC
and makes it easier to handle and test the SENDME cells in an isolated way.
This commit only moves code. No behavior change.
Signed-off-by: David Goulet <dgoulet@torproject.org>
The nodelist_idx for each node_t serves as a unique identifier for
the node, so we can use a bitarray to hold all the excluded
nodes, and then remove them from the smartlist.
Previously use used smartlist_subtract(sl, excluded), which is
O(len(sl)*len(excluded)).
We can use this function in other places too, but this is the one
that showed up on the profiles of 30291.
Closes ticket 30307.
This command does not fit perfectly with the others, since its
second argument is optional and may contain equal signs. Still,
it's probably better to squeeze it into the new metaformat, since
doing so allows us to remove several pieces of the old
command-parsing machinery.
The two options are mutually exclusive, since otherwise an entry
like "Foo" would be ambiguous. We want to have the ability to treat
entries like this as keys, though, since some controller commands
interpret them as flags.
(This should be all of the command that work nicely with positional
arguments only.)
Some of these commands should probably treat extra arguments as
incorrect, but for now I'm trying to be careful not to break
any existing users.
The first line break in particular was mishandled: it was discarded
if no arguments came before it, which made it impossible to
distinguish arguments from the first line of the body.
To solve this, we need to allocate a copy of the command rather than
using NUL to separate it, since we might have "COMMAND\n" as our input.
Fixes ticket 29984.
There _is_ an underlying logic to these commands, but it isn't
wholly uniform, given years of tweaks and changes. Fortunately I
think there is a superset that will work.
This commit adds a parser for some of the most basic cases -- the
ones currently handled by getargs_helper() and some of the
object-taking ones. Soon will come initial tests; then I'll start using
the parser.
After that, I'll expand the parser to handle the other cases that come
up in the controller protocol.
We have checks in various places in mainlook.c to make sure that
events are initialized before we invoke any periodic_foo() functions
on them. But now that each subsystem will own its own periodic
events, it will be cleaner if we don't assume that they are all
setup or not.
The end goal here is to move the periodic callback to their
respective modules, so that mainloop.c doesn't have to include so
many other things.
This patch doesn't actually move any of the callbacks out of
mainloop.c yet.
In this patch we lower the log level of the failures for the three calls
to unlink() in networkstatus_set_current_consensus(). These errors might
trigger on Windows because the memory mapped consensus file keeps the
file in open state even after we have close()'d it. Windows will then
error on the unlink() call with a "Permission denied" error.
The consequences of ignoring these errors is that we leave an unused
file around on the file-system, which is an easier way to fix this
problem right now than refactoring networkstatus_set_current_consensus().
See: https://bugs.torproject.org/29930
In "make test-network-all", test IPv6-only v3 single onion services,
using the chutney network single-onion-v23-ipv6-md. This test will
not pass until 23588 has been merged.
Closes ticket 27251.
Disable padding via limit check and machine condition. Limits cause us to stop
sending padding. Machine conditions cause the machines to be shut down, and
not restarted.
In 0.3.4 and later, these functions are declared in rephist.h:
STATIC uint64_t find_largest_max(bw_array_t *b);
STATIC void commit_max(bw_array_t *b);
STATIC void advance_obs(bw_array_t *b);
But in 0.2.9, they are declared in rephist.c and test_relay.c.
So compilers fail with a "must use 'struct' tag" error.
We add the missing struct typedef in test_relay.c, to match the
declarations in rephist.c.
(Merge commit 813019cc57 moves these functions into rephist.h instead.)
Fixes bug 30184; not in any released version of Tor.
When releasing OpenSSL patch-level maintenance updates,
we do not want to rebuild binaries using it.
And since they guarantee ABI stability, we do not have to.
Without this patch, warning messages were produced
that confused users:
https://bugzilla.opensuse.org/show_bug.cgi?id=1129411
Fixes bug 30190; bugfix on 0.2.4.2-alpha commit 7607ad2bec
Signed-off-by: Bernhard M. Wiedemann <bwiedemann@suse.de>
In 0.3.4 and later, we declare write_array as:
extern struct bw_array_t *write_array;
...
typedef struct bw_array_t bw_array_t;
But in 0.2.9, we declare write_array as:
typedef struct bw_array_t bw_array_t;
extern bw_array_t *write_array;
And then again in rephist.c:
typedef struct bw_array_t bw_array_t;
So some compilers fail with a duplicate declaration error.
We backport 684b396ce5, which removes the duplicate declaration.
And this commit deals with the undeclared type error.
Backports a single line from merge commit 813019cc57.
Fixes bug 30184; not in any released version of Tor.
We need to encode here instead of doing escaped(), since fwict
escaped() does not currently handle NUL bytes.
Also, use warn_if_nul_found in more cases to avoid duplication.
The smartlist functions take great care to reset unused pointers inside
the smartlist memory to NULL.
The function smartlist_remove_keeporder does not clear memory in such
way when elements have been removed. Therefore call memset after the
for-loop that removes elements. If no element is removed, it is
effectively a no-op.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
The smartlist code takes great care to set all unused pointers inside
the smartlist memory to NULL. Check if this is also the case after
modifying the smartlist multiple times.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Previously, our use of abort() would break anywhere that we didn't
include stdlib.h. This was especially troublesome in case where
tor_assert_nonfatal() was used with ALL_BUGS_ARE_FATAL, since that
one seldom gets tested.
As an alternative, we could have just made this header include
stdlib.h. But that seems bloaty.
Fixes bug 30189; bugfix on 0.3.4.1-alpha.
Coverity doesn't like to see a path where we test a pointer for
NULL if we have already ready dereferenced the pointer on that
path. While in this case, the check is not needed, it's best not to
remove checks from the unit tests IMO. Instead, I'm adding an
earlier check, so that coverity, when analyzing this function, will
think that we have always checked the pointer before dereferencing
it.
Closes ticket 30180; CID 1444641.
Use a table-based lookup to find the right command handler. This
will serve as the basement for several future improvements, as we
improve the API for parsing commands.
This should please coverity, and fix CID 1415721. It didn't
understand that networkstatus_get_param() always returns a value
between its minimum and maximum values.
This should please coverity, and fix CID 1415722. It didn't
understand that networkstatus_get_param() always returns a value
between its minimum and maximum values.
This should please coverity, and fix CID 1415723. It didn't understand
that networkstatus_get_param() always returns a value between its
minimum and maximum values.
The logic here should be "use versions or free it". The "free it"
part was previously in a kind of obfuscated place, so coverity
wasn't sure it was invoked as appropriate. CID 1437436.
The function compat_getdelim_ is used for tor_getline if tor is compiled
on a system that lacks getline and getdelim. These systems should be
very rare, considering that getdelim is POSIX.
If this system is further a 32 bit architecture, it is possible to
trigger a double free with huge files.
If bufsiz has been already increased to 2 GB, the next chunk would
be 4 GB in size, which wraps around to 0 due to 32 bit limitations.
A realloc(*buf, 0) could be imagined as "free(*buf); return malloc(0);"
which therefore could return NULL. The code in question considers
that an error, but will keep the value of *buf pointing to already
freed memory.
The caller of tor_getline() would free the pointer again, therefore
leading to a double free.
This code can only be triggered in dirserv_read_measured_bandwidths
with a huge measured bandwith list file on a system that actually
allows to reach 2 GB of space through realloc.
It is not possible to trigger this on Linux with glibc or other major
*BSD systems even on unit tests, because these systems cannot reach
so much memory due to memory fragmentation.
This patch is effectively based on the penetration test report of
cure53 for curl available at https://cure53.de/pentest-report_curl.pdf
and explained under section "CRL-01-007 Double-free in aprintf() via
unsafe size_t multiplication (Medium)".
If the concatenation of connection buffer and the buffer of linked
connection exceeds INT_MAX bytes, then buf_move_to_buf returns -1 as an
error value.
This value is currently casted to size_t (variable n_read) and will
erroneously lead to an increasement of variable "max_to_read".
This in turn can be used to call connection_buf_read_from_socket to
store more data inside the buffer than expected and clogging the
connection buffer.
If the linked connection buffer was able to overflow INT_MAX, the call
of buf_move_to_buf would have previously internally triggered an integer
overflow, corrupting the state of the connection buffer.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Many buffer functions have a hard limit of INT_MAX for datalen, but
this limitation is not enforced in all functions:
- buf_move_all may exceed that limit with too many chunks
- buf_move_to_buf exceeds that limit with invalid buf_flushlen argument
- buf_new_with_data may exceed that limit (unit tests only)
This patch adds some annotations in some buf_pos_t functions to
guarantee that no out of boundary access could occur even if another
function lacks safe guards against datalen overflows.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
If the concatenation of connection buffer and the buffer of linked
connection exceeds INT_MAX bytes, then buf_move_to_buf returns -1 as an
error value.
This value is currently casted to size_t (variable n_read) and will
erroneously lead to an increasement of variable "max_to_read".
This in turn can be used to call connection_buf_read_from_socket to
store more data inside the buffer than expected and clogging the
connection buffer.
If the linked connection buffer was able to overflow INT_MAX, the call
of buf_move_to_buf would have previously internally triggered an integer
overflow, corrupting the state of the connection buffer.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Many buffer functions have a hard limit of INT_MAX for datalen, but
this limitation is not enforced in all functions:
- buf_move_all may exceed that limit with too many chunks
- buf_move_to_buf exceeds that limit with invalid buf_flushlen argument
- buf_new_with_data may exceed that limit (unit tests only)
This patch adds some annotations in some buf_pos_t functions to
guarantee that no out of boundary access could occur even if another
function lacks safe guards against datalen overflows.
[This is a backport of the submitted patch to 0.2.9, where the
buf_move_to_buf and buf_new_with_data functions did not exist.]
Fixes bug 29922; bugfix on 0.2.9.3-alpha when we tried to capture
all these warnings. No need to backport any farther than 0.3.5,
though -- these warnings don't cause test failures before then.
This one was tricky to find because apparently it only happened on
_some_ windows builds.
In current NSS versions, these ciphersuites don't work with
SSL_ExportKeyingMaterial(), which was causing relays to fail when
they tried to negotiate the v3 link protocol authentication.
Fixes bug 29241; bugfix on 0.4.0.1-alpha.
And fix the documentation on the function: it does produce trailing
"="s as padding.
Also remove all checks for the return value, which were redundant anyway,
because the function never failed.
Part of 29660.
... and ed25519_public_to_base64(). Also remove all checks for the return
values, which were redundant anyway, because the functions never failed.
Part of 29960.
This test was disabled in 0.4.0 and later, but the fix in #29298 was only
merged to 0.4.1. So this test will never be re-enabled in 0.4.0.
Part of 29500.
Our monotime mocking forces us to call monotime_init() *before* we set the
mocked time value. monotime_init() thus stores the first ratchet value at
whatever the platform is at, and then we set fake mocked time to some later
value.
If monotime_init() gets a value from the host that is greater than what we
choose to mock time at for our unittests, all subsequent monotime_abosolute()
calls return zero, which breaks all unittests that depend on time moving
forward by updating mocked monotime values.
So, we need to adjust our mocked time to take the weird monotime_init() time
into account, when we set fake time.
getpid() can be really expensive sometimes, and it can fail to
detect some kind of fork+prng mistakes, so we need to avoid it if
it's safe to do so.
This patch might slow down fast_prng a lot on any old operating
system that lacks a way to prevent ram from being inherited, AND
requires a syscall for any getpid() calls. But it should make sure
that we either crash or continue safely on incorrect fork+prng usage
elsewhere in the future.
When classifying a client's selection of TLS ciphers, if the client
ciphers are not yet available, do not cache the result. Previously,
we had cached the unavailability of the cipher list and never looked
again, which in turn led us to assume that the client only supported
the ancient V1 link protocol. This, in turn, was causing Stem
integration tests to stall in some cases. Fixes bug 30021; bugfix
on 0.2.4.8-alpha.
When we fixed 28614, our answer was "if we failed to load the
consensus on windows and it had a CRLF, retry it." But we logged
the failure at "warn", and we only logged the retry at "info".
Now we log the retry at "notice", with more useful information.
Fixes bug 30004.
This is just in case there is some rogue platform that uses a
nonstandard value for SEEK_*, and does not define that macro in
unistd.h. I think that's unlikely, but it's conceivable.
Previously we used time(NULL) to set the Expires: header in our HTTP
responses. This made the actual contents of that header untestable,
since the unit tests have no good way to override time(), or to see
what time() was at the exact moment of the call to time() in
dircache.c.
This gave us a race in dir_handle_get/status_vote_next_bandwidth,
where the time() call in dircache.c got one value, and the call in
the tests got another value.
I'm applying our regular solution here: using approx_time() so that
the value stays the same between the code and the test. Since
approx_time() is updated on every event callback, we shouldn't be
losing any accuracy here.
Fixes bug 30001. Bug introduced in fb4a40c32c4a7e5; not in any
released Tor.
