Move everything to its own function in order to better log, document and tests
the introduction point validation process.
Signed-off-by: David Goulet <dgoulet@torproject.org>
When consensus changes, we also need to update the circuit INTRO2 defenses
enabled flag and not only the token bucket.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Remove the public functions returning the HS DoS consensus param or default
values as it is exclusively used internally now.
Rename the param_* variables to consensus_param_* for better code semantic.
Finally, make some private functions available to unit tests.
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit makes it that the hs_dos.c file only uses the consensus parameter
variables set when we initialize and when the consensus changes.
There is no need to call each time networkstatus_get_param(), which is
expensive, when we want access to a consensus value.
Signed-off-by: David Goulet <dgoulet@torproject.org>
A bit cleaner especially that the next commit(s) will make the consensus param
interface private to hs_dos.c so we expose as little as we can outside of the
subsystem.
Part of #30924
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit makes tor add the DoS cell extension to the ESTABLISH_INTRO cell
if the defense is enabled on the service side with a torrc option.
Furthermore, the cell extension is only added if the introduction point
supports it. The protover version HSIntro=5 is looked for.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Make it clear that these functions return the consensus param only.
Introduction point can not set those values with a torrc option.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Previously, v3 single onion services failed when all intro nodes were
unreachable via a 1-hop path. Now, we select intros that are only available
via a 3-hop path, and use a 3-hop path to connect to them.
Fixes bug 23507; bugfix on 0.3.2.1-alpha.
Previously, we used a 1-hop path when a single onion rend failed
immediately, and a 3-hop path when it failed after trying to build
a circuit.
Fixes bug 23818; bugfix on 0.3.2.1-alpha.
In case the consensus parameters for the rate/burst changes, we need to update
all already established introduction circuits to the newest value.
This commit introduces a "get all intro circ" function from the HS circuitmap
(v2 and v3) so it can be used by the HS DoS module to go over all circuits and
adjust the INTRODUCE2 token bucket parameters.
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>
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.
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.
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().
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.
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>
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.
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.
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>
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.
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
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).
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.
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
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.
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.
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.
(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.
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