Largest change is in the FFI crate.
With 2024 (but not 2021) edition unsafe code
inside unsafe functions should be marked separately
so we can mark exactly the code that is unsafe.
Some CFFI functions even have no unsafe code inside.
Most interesting change is that .strdup()
functions are not marked as unsafe anymore.
They are allocating memory and return raw pointers,
but there is nothing unsafe about it.
Only using the returned raw pointers is unsafe.
This way calls to .strdup() don't have to be marked
with unsafe{} blocks.
Unifies internal naming of single/direct/1:1/normal chats
to match the naming used in the API.
Closes: #8368
Signed-off-by: Jagoda Ślązak <jslazak@jslazak.com>
---------
Signed-off-by: Jagoda Ślązak <jslazak@jslazak.com>
BREAKING CHANGE: provider lookup APIs were removed from CFFI and JSON-RPC.
also removes offline provider database code and generated provider data,
provider-specific fields in configure/transport paths, and REPL providerinfo.
Heartbeat notifications are only used on iOS for classic mail servers
but both code and privacy wise (notification server sees IP addresses from those users)
not something we want to support any longer (was discussed with bjoern).
Unpublished relays aren't shown in the list of relays anymore, and can't
be deleted manually. Therefore, we want to automatically delete them in
order to make space for more relays when the limit (5) is reached and
the user wants to add another relay.
Automatically remove relays that are hidden (`is_published=0`) and
haven't been used to receive new messages for over 90 days.
Closes: #8384
Signed-off-by: Jagoda Ślązak <jslazak@jslazak.com>
BREAKING CHANGE: UIs should use `list_transports()` rather than `list_transports_ex()`, because unpublished transports count as removed from the user point of view, and should not be shown in the relay list anymore.
Fix https://github.com/chatmail/core/issues/8250. Not sure why anyone
would tamper with the link, but maybe the name gets ellipsized because
it is very long, or maybe we decide to ellipsize more aggressively in
the future.
The fix is easy enough, just set the GroupNameTimestamp when creating
the channel, so that `HeaderDef::ChatGroupNameTimestamp` gets set when
sending a message and the logic in
`apply_chat_name_avatar_and_description_changes()` recognizes the
incoming name's timestamp as newer than `chat_group_name_timestamp`
(which is 0 right after joining a chat).
The test is somewhat hacky and depends on the title being the last
parameter in the invite code URL, but this is fine; if we ever change
that, then the test will fail and we need to modify it.
This also removes some wrong doc comments.
Since groups are unpromoted until sending a first message, the same fix isn't needed for groups.
Fix https://github.com/chatmail/core/issues/8195
Supersedes https://github.com/chatmail/core/pull/8217
The most interesting change is in `delete_expired_imap_messages()`
because there, messages are marked for deletion on single-device
chatmail profiles.
The logic in `delete_expired_imap_messages()` was wrong before, and
pre-messages were not deleted at all. This is fixed by also querying
`pre_rfc724_mid` in addition to `rfc724_mid` from the `msgs` table.
In order not to make the SQL statement too complex, I split it into two.
WRT tests:
- `test_immediate_autodelete()` tests the auto-deletion;
`test_imap_autodelete_fully_downloaded_msg()` tests that even for a
message that is split into pre- and post-message, both messages are
deleted.
- A lot of tests test that if bcc_self is on, messages are not
auto-deleted. E.g. `test_one_account_send_bcc_setting()` and
`test_markseen_message_and_mdn()` relies on the fact that messages stay
on the server when bcc_self is on.
- Unfortunately, it is not possible to test that messages are only
deleted for chatmail servers, because we don't have any tests that use a
non-chatmail server.
E.g. rename location::is_sending_locations_to_chat to location::is_sending_to_chat.
Then import only the location module and use it with location:: prefix,
similarly to how e.g. std::fs or std::tokio::fs avoids using "fs" or "file"
in function names.
Remove unused info_only option from `get_chat_msgs_ex()`.
This option was meant to show an "audit log" of a group, i.e. only the
info messages. This feature was removed again from Desktop, but the
option still lingered around in Core.
This also adds a doc comment to the JsonRPC functions, because I
wanted to note somewhere that the parameter is deprecated, and I needed
some place to put this note.
This causes problems for Delta Chat Desktop at
<https://github.com/deltachat/deltachat-desktop/pull/6278>
even though the logic was originally introduced for iOS.
If the problem remains on iOS,
heuristics can be added into iOS UI.
After talking with r10s:
For spring cleaning, remove the largely-unused things that can be done a
bit.
Most private messengers (WhatsApp/Signal/...) do not have this feature,
and we do not want to become Matrix where every client has different,
partly-incompatible features.
I used some AI to draft a first version of this, and then reworked it.
This is one of multiple possibilities to fix
https://github.com/chatmail/core/issues/8041: For bots, the IncomingMsg
event is not emitted when the pre-message arrives, only when the
post-message arrives. Also, post-messages are downloaded immediately,
not after all the small messages are downloaded.
The `get_next_msgs()` API is deprecated. Instead, bots need to listen to
the IncomingMsg event in order to be notified about new events. Is this
acceptable for bots?
THE PROBLEM THAT WAS SOLVED BY THIS:
With pre-messages, it's hard for bots to wait for the message to be fully downloaded and then process it.
Up until now, bots used get_next_msgs() to query the unprocessed messages, then set last_msg_id after processing a message to that they won't process it again.
But this will now also return messages that were not fully downloaded.
ALTERNATIVES:
In the following, I will explain
the alternatives, and for why it's not so easy to just make the
`get_next_msgs()` API work. If it's not understandable, I'm happy to
elaborate more.
Core can't just completely ignore the pre-message for two reasons:
- If a post-message containing a Webxdc arrives later, and some webxdc updates arrive in the meantime, then these updates will be lost.
- The post-message doesn't contain the text (reasoning was to avoid duplicate text for people who didn't upgrade yet during the 2.43.0 rollout)
There are multiple solutions:
- Add the message as hidden in the database when the pre-message arrives.
- When the post-message arrives and we want to make it available for bots, we need to update the msg_id because of how the `get_next_msgs()` API works. This means that we need to update all webxdc updates that reference this msg_id.
- Alternatively, we could make webxdc's reference the rfc724_mid instead of the msg_id, so that we don't need stable msg_ids anymore
- Alternatively, we could deprecate `get_next_msgs()`, and ask bots to use plain events for message processing again. It's not that bad; worst case, the bot crashes and then forgets to react to some messages, but the user will just try again. And if some message makes the bot crash, then it might actually be good not to try and process it again.
- Store the pre-message text and `PostMsgMetadata` (or alternatively, the whole mime) in a new database table. Wait with processing it until the post-message arrives.
Additionally, the logic that small messages are downloaded before post-messages should be disabled for bots, in order to prevent reordering.
Follow-up to https://github.com/chatmail/core/pull/7994/, in order to
prevent clashes with other things that are called `Transport`, and in
order to make the struct name more greppable
Closes https://github.com/chatmail/core/issues/7980.
Unpublished transports are not advertised to contacts, and self-sent messages are not sent there, so that we don't cause extra messages to the corresponding inbox, but can still receive messages from contacts who don't know the new relay addresses yet.
- This adds `list_transports_ex()` and `set_transport_unpublished()` JsonRPC functions
- By default, transports are published, but when updating, all existing transports except for the primary one become unpublished in order not to break existing users that followed https://delta.chat/legacy-move
- It is not possible to unpublish the primary transport, and setting a transport as primary automatically sets it to published
An alternative would be to change the existing list_transports API rather than adding a new one list_transports_ex. But to be honest, I don't mind the _ex prefix that much, and I am wary about compatibility issues. But maybe it would be fine; see b08ba4bb8 for how this would look.
fix https://github.com/chatmail/core/issues/7766
Implementation notes:
- Descriptions are only sent with member additions, when the description
is changed, and when promoting a previously-unpromoted group, in order
not to waste bandwith.
- Descriptions are not loaded everytime a chat object is loaded, because
they are only needed for the profile. Instead, they are in their own
table, and can be loaded with their own JsonRPC call.
---------
Co-authored-by: iequidoo <117991069+iequidoo@users.noreply.github.com>
Also remove "you can now call 'configure'" from the REPL output, probably users of the REPL tool can
read the code documentation to know when 'configure' should be run.
Adds an api to get all ui config keys. There already is an option to get
all normal config keys (`"sys.config_keys"`), but before this pr there
was no way to get all `ui.*` config keys.
#### Why is this api needed?
For webxdc cleanup on desktop, which stores window position in a ui
config key (such as `ui.desktop.webxdcBounds.676464`) as soon as a
webxdc is opened since many versions now. So listing all ui keys is a
good way for us to find out which webxdc may have web data stored.
unfortunately electron does not (yet?) have a way to list all origins
that have web-data like android does, so this is the next best thing we
can do before itterating all possible ids, see also
https://github.com/deltachat/deltachat-desktop/issues/5758.
#### Why is this only a jsonrpc api and not another special/virtual
config key like `"sys.config_keys"`?
r10s indicated that `ui.*`-config keys are barely used
(https://github.com/deltachat/deltachat-desktop/issues/5790#issuecomment-3598512802),
so I thought it makes more sense to add it as dedicated api which's
existentence is checked by the typechecker, so it will be easier to not
miss it when we should remove the api again in the future.
But we could also do a dedicated special/virtual config key for it, if
you think that is better, this is easy to change.
---------
Co-authored-by: iequidoo <117991069+iequidoo@users.noreply.github.com>
Add `chat::forward_msgs_2ctx()` which takes another context as a parameter and forwards messages to
it and its jsonrpc wrapper `CommandApi::forward_messages_to_account()`.
This API allows to check if the message with
given ID exists and distinguish between
message not existing and database error.
It might also be faster than
checking messages one by one
if multiple messages need to be checked
because of using a single SQL transaction.
New APIs are JSON-RPC method stop_background_fetch(),
Rust method Accounts.stop_background_fetch()
and C method dc_accounts_stop_background_fetch().
These APIs allow to cancel background fetch early
even before the initially set timeout,
for example on Android when the system calls
`Service.onTimeout()` for a `dataSync` foreground service.
Follow-up for https://github.com/chatmail/core/pull/7042, part of
https://github.com/chatmail/core/issues/6884.
This will make it possible to create invite-QR codes for broadcast
channels, and make them symmetrically end-to-end encrypted.
- [x] Go through all the changes in #7042, and check which ones I still
need, and revert all other changes
- [x] Use the classical Securejoin protocol, rather than the new 2-step
protocol
- [x] Make the Rust tests pass
- [x] Make the Python tests pass
- [x] Fix TODOs in the code
- [x] Test it, and fix any bugs I find
- [x] I found a bug when exporting all profiles at once fails sometimes,
though this bug is unrelated to channels:
https://github.com/chatmail/core/issues/7281
- [x] Do a self-review (i.e. read all changes, and check if I see some
things that should be changed)
- [x] Have this PR reviewed and merged
- [ ] Open an issue for "TODO: There is a known bug in the securejoin
protocol"
- [ ] Create an issue that outlines how we can improve the Securejoin
protocol in the future (I don't have the time to do this right now, but
want to do it sometime in winter)
- [ ] Write a guide for UIs how to adapt to the changes (see
https://github.com/deltachat/deltachat-android/pull/3886)
## Backwards compatibility
This is not very backwards compatible:
- Trying to join a symmetrically-encrypted broadcast channel with an old
device will fail
- If you joined a symmetrically-encrypted broadcast channel with one
device, and use an old core on the other device, then the other device
will show a mostly empty chat (except for two device messages)
- If you created a broadcast channel in the past, then you will get an
error message when trying to send into the channel:
> The up to now "experimental channels feature" is about to become an officially supported one. By that, privacy will be improved, it will become faster, and less traffic will be consumed.
>
> As we do not guarantee feature-stability for such experiments, this means, that you will need to create the channel again.
>
> Here is what to do:
> • Create a new channel
> • Tap on the channel name
> • Tap on "QR Invite Code"
> • Have all recipients scan the QR code, or send them the link
>
> If you have any questions, please send an email to delta@merlinux.eu or ask at https://support.delta.chat/.
## The symmetric encryption
Symmetric encryption uses a shared secret. Currently, we use AES128 for
encryption everywhere in Delta Chat, so, this is what I'm using for
broadcast channels (though it wouldn't be hard to switch to AES256).
The secret shared between all members of a broadcast channel has 258
bits of entropy (see `fn create_broadcast_shared_secret` in the code).
Since the shared secrets have more entropy than the AES session keys,
it's not necessary to have a hard-to-compute string2key algorithm, so,
I'm using the string2key algorithm `salted`. This is fast enough that
Delta Chat can just try out all known shared secrets. [^1] In order to
prevent DOS attacks, Delta Chat will not attempt to decrypt with a
string2key algorithm other than `salted` [^2].
## The "Securejoin" protocol that adds members to the channel after they
scanned a QR code
This PR uses the classical securejoin protocol, the same that is also
used for group and 1:1 invitations.
The messages sent back and forth are called `vg-request`,
`vg-auth-required`, `vg-request-with-auth`, and `vg-member-added`. I
considered using the `vc-` prefix, because from a protocol-POV, the
distinction between `vc-` and `vg-` isn't important (as @link2xt pointed
out in an in-person discussion), but
1. it would be weird if groups used `vg-` while broadcasts and 1:1 chats
used `vc-`,
2. we don't have a `vc-member-added` message yet, so, this would mean
one more different kind of message
3. we anyways want to switch to a new securejoin protocol soon, which
will be a backwards incompatible change with a transition phase. When we
do this change, we can make everything `vc-`.
[^1]: In a symmetrically encrypted message, it's not visible which
secret was used to encrypt without trying out all secrets. If this does
turn out to be too slow in the future, then we can remember which secret
was used more recently, and and try the most recent secret first. If
this is still too slow, then we can assign a short, non-unique (~2
characters) id to every shared secret, and send it in cleartext. The
receiving Delta Chat will then only try out shared secrets with this id.
Of course, this would leak a little bit of metadata in cleartext, so, I
would like to avoid it.
[^2]: A DOS attacker could send a message with a lot of encrypted
session keys, all of which use a very hard-to-compute string2key
algorithm. Delta Chat would then try to decrypt all of the encrypted
session keys with all of the known shared secrets. In order to prevent
this, as I said, Delta Chat will not attempt to decrypt with a
string2key algorithm other than `salted`
BREAKING CHANGE: A new QR type AskJoinBroadcast; cloning a broadcast
channel is no longer possible; manually adding a member to a broadcast
channel is no longer possible (only by having them scan a QR code)
This way, the statistics / self-reporting bot will be made into an
opt-in regular sending of statistics, where you enable the setting once
and then they will be sent automatically. The statistics will be sent to
a bot, so that the user can see exactly which data is being sent, and
how often. The chat will be archived and muted by default, so that it
doesn't disturb the user.
The collected statistics will focus on the public-key-verification that
is performed while scanning a QR code. Later on, we can add more
statistics to collect.
**Context:**
_This is just to give a rough idea; I would need to write a lot more
than a few paragraphs in order to fully explain all the context here_.
End-to-end encrypted messengers are generally susceptible to MitM
attacks. In order to mitigate against this, messengers offer some way of
verifying the chat partner's public key. However, numerous studies found
that most popular messengers implement this public-key-verification in a
way that is not understood by users, and therefore ineffective - [a 2021
"State of Knowledge" paper
concludes:](https://dl.acm.org/doi/pdf/10.1145/3558482.3581773)
> Based on our evaluation, we have determined that all current E2EE
apps, particularly when operating in opportunistic E2EE mode, are
incapable of repelling active man-in-the-middle (MitM) attacks. In
addition, we find that none of the current E2EE apps provide better and
more usable [public key verification] ceremonies, resulting in insecure
E2EE communications against active MitM attacks.
This is why Delta Chat tries to go a different route: When the user
scans a QR code (regardless of whether the QR code creates a 1:1 chat,
invites to a group, or subscribes to a broadcast channel), a
public-key-verification is performed in the background, without the user
even having to know about this.
The statistics collected here are supposed to tell us whether Delta Chat
succeeds to nudge the users into using QR codes in a way that is secure
against MitM attacks.
**Plan for statistics-sending:**
- [x] Get this PR reviewed and merged (but don't make it available in
the UI yet; if Android wants to make a release in the meantime, I will
create a PR that removes the option there)
- [x] Set the interval to 1 week again (right now, it's 1 minute for
testing)
- [ ] Write something for people who are interested in what exactly we
count, and link to it (see `TODO[blog post]` in the code)
- [ ] Prepare a short survey for participants
- [ ] Fine-tune the texts at
https://github.com/deltachat/deltachat-android/pull/3794, and get it
reviewed and merged
- [ ] After the next release, ask people to enable the
statistics-sending
If we use modules (which are actually namespaces), we can use shorter names. Another approach is to
only use modules for internal code incapsulation and use full names like deltachat-ffi does.
