There is no need to preemptively add the keys to the store oneself.
SessionBuilder will take care of this for us. What's more, this will
prevent IdentityKeys from otherwise invalid bundles to show up in our
UI.
If we detect our own ID is not in our own devicelist on receiving an
update, we reannounce ourselves. This used to have the side effect of
modifying the list of devices we thought were in the update set, causing
us to accidentally build a session with ourselves.
This lead to our own key being set to TRUSTED_INACTIVE, resulting in red
lock icons on messages sent by the own device.
We fix this by having publishOwnDeviceId() operate on a copy of the
original set. This commit also includes a db migration which deletes
sessions with oneself and sets own keys back to TRUSTED.
If PEP publish tries are repeatedly triggered by empty PEP updates, stop
attempting to publish after 3 tries. This should work around broken PEP
implementations in older ejabberd and OpenFire versions.
XmppAxolotlMessage is now entirely responsible for handling encryption
and decryption of messages, only leveraging XmppAxolotlSession as a
packing/unpacking primitive for payload keys.
Removed pseudo-dead session generation code step from prepareMessage
function, as sessions have been created by invoking the
TrustKeysActivity for a while now.
Added prepareKeyTransportMessage function, which creates a message with
no payload. The key that is packed into the header keyElements can then
be used for other purposes (e.g. encrypted file transfer).
Moves SQLiteAxolotlStore and XmppAxolotlSession into proper classes.
IdentityKeys trust statuses are now cached in an LruCache to prevent
hammering the database when rendering the UI.
We introduce a new trust state: INACTIVE. This state is intended for
old keys that have been removed.
When a TRUSTED device is removed from the PEP devicelist, it's status
will be set to INACTIVE. INACTIVE keys are shown in the UI as greyed
out, non-interactible key rows. Messages are not encrypted for INACTIVE
devices.
When an INACTIVE device reappears in PEP, or a message is received from
an INACTIVE device, it is set back to trusted.
If the contact (or the own account) has keys that have UNDECIDED trust,
we now drop the user into the new TrustKeysActivity, where they have to
decide for each new key whether it should be TRUSTED or UNTRUSTED.
Tag sent messages with own fingerprint, set own fingerprint as always
trusted, include own fingerprint in database trust search, explicitly
reset trust colorfilter
Any time a new session is established, call syncRosterToDisk() to ensure
that on subsequent restoreFromDatabase() calls, the roster is actually
available. This is important so that initAccountServices() can properly
initialize the SessionMap. This prevents a race condition where after
adding a new account and initiating sessions with it, if the app is
killed (e.g. by reinstall) before triggering a syncRosterToDisk(),
subsequent restores will not have the roster available, leading to
missing XmppAxolotlSessions in the SessionMap cache. As a result of
this, a new session was initiated when sending a new message, and
received messages could not be tagged with the originating session's
fingerprint.
As an added sanity check, go to the database to confirm no records are
present before creating fresh XmppAxolotlSession objects (both in the
sending and receiving case).
Wipe session cache to prevent stale sessions being used. Wipe fetch
status cache to enable recreation of sessions. Regenerate deviceId, so
that foreign devices will talk to us again.
Messages are now tagged with the IdentityKey fingerprint of the
originating session. IdentityKeys have one of three trust states:
undecided (default), trusted, and untrusted/not yet trusted.
EditAccountActivity now show own fingerprint, and gives an option to
regenerate local keying material (and wipe all sessions associated with
the old keys in the process).
It also now displays a list of other own devices, and gives an option to
remove all but the current device.
No longer store own device ID (so that we don't encrypt messages for
ourselves), verify that own device ID is present in update list
(otherwise republish), reflect update in UI.
When receiving a message, only remember the XmppAxolotlSession wrapper
if the prospective session was actually established. This prevents us
from erroneously adding empty sessions that are never established using
received PreKeyWhisperMessages, which would lead to errors if we try to
use them for sending.
The trust-on-first-use policy leads to problems when receiving messages
from two different devices of a contact before sending a message to them
(as their IdentityKeys will not have been added yet). Since session
trust will be managed externally anyway, this change is not a security
problem, and will allow us to decrypt messages from yet-untrusted
sessions.
