When cleaning up extra circuits that we've opened for performance reason, we
need to count all the introduction circuit and not only the established ones
else we can end up with too many introduction points.
This also adds the check for expiring nodes when serving an INTRODUCE cell
since it's possible old clients are still using them before we have time to
close them.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
To upload a HS descriptor, this commits makes it that we wait for all
introduction point to be fully established.
Else, the HS ends up uploading a descriptor that may contain intro points
that are not yet "valid" meaning not yet established or proven to work. It
could also trigger three uploads for the *same* descriptor if every intro
points takes more than 30 seconds to establish because of desc_is_dirty
being set at each intro established.
To achieve that, n_intro_points_established varialbe is added to the
rend_service_t object that is incremented when we established introduction
point and decremented when we remove a valid intro point from our list.
The condition to upload a descriptor also changes to test if all intro
points are ready by making sure we have equal or more wanted intro points
that are ready.
The desc_id_dirty flag is kept to be able to still use the
RendInitialPostPeriod option.
This partially fixes#13483.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
There is a case where if the introduction circuit fails but the node is
still in the consensus, we clean up the intro point and choose an other one.
This commit fixes that by trying to reuse the existing intro point with a
maximum value of retry.
A retry_nodes list is added to rend_services_introduce() and when we remove
an invalid intro points that fits the use case mentionned before, we add the
node to the retry list instead of removing it. Then, we retry on them before
creating new ones.
This means that the requirement to remove an intro point changes from "if no
intro circuit" to "if no intro circuit then if no node OR we've reached our
maximum circuit creation count".
For now, the maximum retries is set to 3 which it completely arbitrary. It
should also at some point be tied to the work done on detecting if our
network is down or not.
Fixes#8239
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
The reasoning for refactoring this function is that removing the
introduction point adaptative algorithm (#4862) ended up changing quite a
bit rend_services_introduce(). Also, to fix some open issues (#8239, #8864
and #13483), this work had to be done.
First, this removes time_expiring variable in an intro point object and
INTRO_POINT_EXPIRATION_GRACE_PERIOD trickery and use an expiring_nodes list
where intro nodes that should expire are moved to that list and cleaned up
only once the new descriptor is successfully uploaded. The previous scheme
was adding complexity and arbitrary timing to when we expire an intro point.
We keep the intro points until we are sure that the new descriptor is
uploaded and thus ready to be used by clients. For this,
rend_service_desc_has_uploaded() is added to notify the HS subsystem that
the descriptor has been successfully uploaded. The purpose of this function
is to cleanup the expiring nodes and circuits if any.
Secondly, this adds the remove_invalid_intro_points() function in order to
split up rend_services_introduce() a bit with an extra modification to it
that fixes#8864. We do NOT close the circuit nor delete the intro point if
the circuit is still alive but the node was removed from the consensus. Due
to possible information leak, we let the circuit and intro point object
expire instead.
Finally, the whole code flow is simplified and large amount of documentation
has been added to mostly explain the why of things in there.
Fixes#8864
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
This is a way to specify the amount of introduction points an hidden service
can have. Maximum value is 10 and the default is 3.
Fixes#4862
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Rend_add_service() frees its argument on failure; no need to free again.
Fixes bug 16228, bugfix on 0.2.7.1-alpha
Found by coverity; this is CID 1301387.
When set, this limits the maximum number of simultaneous streams per
rendezvous circuit on the server side of a HS, with further RELAY_BEGIN
cells being silently ignored.
This can be modified via "HiddenServiceMaxStreamsCloseCircuit", which
if set will cause offending rendezvous circuits to be torn down instead.
Addresses part of #16052.
Ephemeral services will be listed in rend_services_list at the end of
rend_config_services, so it must check whether directory is non-NULL
before comparing.
This crash happens when reloading config on a tor with mixed configured
and ephemeral services.
Fixes bug #16060. Bugfix on 0.2.7.1-alpha.
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.
"+HSPOST" and the related event changes allow the uploading of HS
descriptors via the control port, and more comprehensive event
monitoring of HS descriptor upload status.
Every callsite that use to allocate a rend_data_t object now use the
rend_data_client/service_create() function.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
These commands allow for the creation and management of ephemeral
Onion ("Hidden") services that are either bound to the lifetime of
the originating control connection, or optionally the lifetime of
the tor instance.
Implements #6411.
Incidently, this fixes a bug where the maximum value was never used when
only using crypto_rand_int(). For instance this example below in
rendservice.c never gets to INTRO_POINT_LIFETIME_MAX_SECONDS.
int intro_point_lifetime_seconds =
INTRO_POINT_LIFETIME_MIN_SECONDS +
crypto_rand_int(INTRO_POINT_LIFETIME_MAX_SECONDS -
INTRO_POINT_LIFETIME_MIN_SECONDS);
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
An introduction point is currently rotated when the amount of INTRODUCE2
cells reached a fixed value of 16384. This makes it pretty easy for an
attacker to inflate that number and observe when the IP rotates which leaks
the popularity of the HS (amount of client that passed through the IP).
This commit makes it a random count between the current value of 16384 and
two times that.
Fixes#15745
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
In #14803, Damian noticed that his Tor sometimes segfaults. Roger noted
that his valgrind gave an invalid write of size one here. Whenever we
use FLEXIBLE_ARRAY_MEMBER, we have to make sure to actually malloc a
thing that's large enough.
Fixes bug #14803, not in any released version of Tor.
Drop the MIN_REND_INITIAL_POST_DELAY on a testing network to 5 seconds,
but keep the default at 30 seconds.
Reduces the hidden service bootstrap to 25 seconds from around 45 seconds.
Change the default src/test/test-network.sh delay to 25 seconds.
Closes ticket 13401.
This allows hidden services to disable the anti-scanning feature
introduced in 0.2.6.2-alpha. With this option not set, a connection
to an unlisted port closes the circuit. With this option set, only
a RELAY_DONE cell is sent.
Closes ticket #14084.
