Remember, you can't check to see if there are N bytes left in a
buffer by doing (buf + N < end), since the buf + N computation might
take you off the end of the buffer and result in undefined behavior.
Fixes 28202; bugfix on 0.2.0.3-alpha.
Before this commit, we would create the descriptor signing key certificate
when first building the descriptor.
In some extreme cases, it lead to the expiry of the certificate which triggers
a BUG() when encoding the descriptor before uploading.
Ticket #27838 details a possible scenario in which this can happen. It is an
edge case where tor losts internet connectivity, notices it and closes all
circuits. When it came back up, the HS subsystem noticed that it had no
introduction circuits, created them and tried to upload the descriptor.
However, in the meantime, if tor did lack a live consensus because it is
currently seeking to download one, we would consider that we don't need to
rotate the descriptors leading to using the expired signing key certificate.
That being said, this commit does a bit more to make this process cleaner.
There are a series of things that we need to "refresh" before uploading a
descriptor: signing key cert, intro points and revision counter.
A refresh function is added to deal with all mutable descriptor fields. It in
turn simplified a bit the code surrounding the creation of the plaintext data.
We keep creating the cert when building the descriptor in order to accomodate
the unit tests. However, it is replaced every single time the descriptor is
uploaded.
Fixes#27838
Signed-off-by: David Goulet <dgoulet@torproject.org>
When storing a descriptor in the client cache, if we are about to replace an
existing descriptor, make sure to close every introduction circuits of the old
descriptor so we don't have leftovers lying around.
Ticket 27471 describes a situation where tor is sending an INTRODUCE1 cell on
an introduction circuit for which it doesn't have a matching intro point
object (taken from the descriptor).
The main theory is that, after a new descriptor showed up, the introduction
points changed which led to selecting an introduction circuit not used by the
service anymore thus for which we are unable to find the corresponding
introduction point within the descriptor we just fetched.
Closes#27471.
Signed-off-by: David Goulet <dgoulet@torproject.org>
It won't be used if there are no authorized client configured. We do that so
we can easily support the addition of a client with a HUP signal which allow
us to avoid more complex code path to generate that cookie if we have at least
one client auth and we had none before.
Fixes#27995
Signed-off-by: David Goulet <dgoulet@torproject.org>
Both client and service had their own code for this. Consolidate into one
place so we avoid duplication.
Closes#27549
Signed-off-by: David Goulet <dgoulet@torproject.org>
Occasionally, key pinning doesn't catch a relay that shares an ed25519
ID with another relay. Log the identity fingerprints and the shared
ed25519 ID when this happens, instead of making a BUG() warning.
Fixes bug 27800; bugfix on 0.3.2.1-alpha.
Commit 488e2b00bf introduced an issue, most
likely introduced by a bad copy paste, that made us stop reading on the
connection if our write bandwidth limit was reached.
The problem is that because "read_blocked_on_bw" was never set, the connection
was never reenabled for reading.
This is most likely the cause of #27813 where bytes were accumulating in the
kernel TCP bufers because tor was not doing reads. Only relays with
RelayBandwidthRate would suffer from this but affecting all relays connecting
to them. And using that tor option is recommended and best practice so many
many relays have it enabled.
Fixes#28089.
