As ratelimit was introduced to avoid reconnecting immediately after disconnecting
in case of bugs in IMAP protocol handling,
connection attempts should only be counted when IMAP is actually used,
i.e. when the first command (LOGIN) is sent.
As per the comment in `receive_imf.rs`, `chat.protected` must be maintained regardless of the
`Config::VerifiedOneOnOneChats`. The only thing that mustn't be done if `VerifiedOneOnOneChats` is
unset (i.e. for non-supporting UIs) is marking chats as "protection broken" because this needs
showing the corresponding dialog to a user.
Drafts mustn't affect sorting of any other messages, they aren't even displayed in the chat
window. Also hidden messages mustn't affect sorting of usual messages. But let hidden messages sort
together with protection messages because hidden messages also can be or not be verified, so let's
preserve this information -- even it's not useful currently, it can be useful in the future
versions.
Before in some places it was correctly calculated by passing the "sent" timestamp to
`calc_sort_timestamp()`, but in other places just the system time was used. In some complex
scenarios like #5088 (restoration of a backup made before a contact verification) it led to wrong
sort timestamps of protection messages and also messages following by them.
But to reduce number of args passed to functions needing to calculate the sort timestamp, add
message timestamps to `struct MimeMessage` which is anyway passed everywhere.
We do not want all_work_done() to return true immediately
after calling start_io(), but only when connection goes idle.
"Connected" state is set immediately after connecting to the server,
but it does not mean there is nothing to do.
This change make all_work_done() return false
from the Connected state and introduces a new Idle
connectivity state that is only set before connection
actually goes idle. For idle state all_work_done() returns true.
From the user point of view both old Connected state
and new Idle state look the same.
This change depends on async-imap update that resets the timeout
every time an `* OK Still here` is received.
Reducing timeout allows to detect lost connections
not later than 6 minutes
because Delta Chat will attempt to finish IDLE with DONE
after 5 minutes without keepalives
and will either get TCP RST directly
or, worst case, wait another minute for TCP socket read timeout.
Ad-hoc groups don't have grpid-s that can be used to identify them across devices and thus wasn't
synced until now.
The same problem already exists for assigning messages to ad-hoc groups and this assignment is done
by `get_parent_message()` and `lookup_chat_by_reply()`. Let's reuse this logic for the
synchronisation, it works well enough and this way we have less surprises than if we try to
implement grpids for ad-hoc groups. I.e. add an `Msgids` variant to `chat::SyncId` analogous to the
"References" header in messages and put two following Message-IDs to a sync message:
- The latest message A having `DownloadState::Done` and the state to be one of `InFresh, InNoticed,
InSeen, OutDelivered, OutMdnRcvd`.
- The message that A references in `In-Reply-To`.
This way the logic is almost the same to what we have in `Chat::prepare_msg_raw()` (the difference
is that we don't use the oldest Message-ID) and it's easier to reuse the existing code.
NOTE: If a chat has only an OutPending message f.e., the synchronisation wouldn't work, but trying
to work in such a corner case has no significant value and isn't worth complicating the code.
- Use TestContextManager
- Actually run receive_imf rather than only mimeparser on "received" messages
- Check that received message parts actually have a padlock
parse_mime_recursive() skips empty text parts,
so there may be no parts as the result of parsing.
In this case an empty part is added.
However, because it is added with parts.push()
rather than add_single_part(),
it is added without a padlock even if the message is encrypted.
`do_add_single_part()` adds padlock (GuaranteeE2EE param)
and should be used to add parts instead.
- Remove "Detected Autocrypt-mime message" logs printed for every incoming Autocrypt message.
- Print only a single line at the beginning of receive_imf with both the Message-ID and seen flag.
- Print Securejoin step only once, inside handle_securejoin_handshake or observe_securejoin_on_other_device.
- Do not log "Not creating ad-hoc group" every time ad-hoc group is not created, log when it is created instead.
- Log ID of the chat where Autocrypt-Gossip for all members is received.
- Do not print "Secure-join requested." for {vg,vc}-request, we already log the step.
- Remove ">>>>>>>>>>>>>>>>>>>>>>>>>" noise from securejoin logs.
Otherwise it looks like the message creating a protected group is not verified. For this, use
`sent_timestamp` of the received message as an upper limit of the sort timestamp (`msgs.timestamp`)
of the protection message. As the protection message is added to the chat earlier, this way its
timestamp is always less or eq than the received message's timestamp.
Test that on the second device of a protected group creator the first message is
`SystemMessage::ChatProtectionEnabled` and the second one is the message populating the group.
Allowing outgoing unencrypted messages in groups with 2 members
breaks the test
`python/tests/test_0_complex_or_slow.py::test_verified_group_vs_delete_server_after`
This centralizes all Securejoin/verification checks and updates in one
place right before add_parts() even before we assign the message to
the chat, so we can decouple chat logic from verification logic.
It's not necessary and in other places like add_contact_to_chat_ex() sync messages are also sent
only if there are no system messages sent like MemberAddedToGroup.
We already synchronise status/footer when we see a self-sent message with a Chat-Version
header. Would be nice to do the same for display name.
But let's do it the same way as for `Config::{MdnsEnabled,ShowEmails}`. Otherwise, if we sync the
display name using the "From" header, smth like `Param::StatusTimestamp` is needed then to reject
outdated display names. Also this timestamp needs to be updated when `Config::Displayname` is set
locally. Also this wouldn't work if system time isn't synchronised on devices. Also using multiple
approaches to sync different config values would lead to more code and bugs while having almost no
value -- using "From" only saves some bytes and allows to sync some things w/o the synchronisation
itself to be enabled. But the latter also can be a downside -- if it's usual synchonisation, you can
(potentially) disable it and share the same email account across people in some organisation
allowing them to have different display names. With using "From" for synchronisation such a
capability definitely requires a new config option.
Motivation: Syncing these options will improve UX in very most cases and should be done. Other
candidates are less clear or are advanced options, we can reconsider that at some point later.
Approach:
- Sync options one-by-one when the corresponding option is set (even if to the same value).
- Don't sync when an option is reset to a default as defaults may differ across client versions.
- Check on both sides that the option should be synced so that if there are different client
versions, the synchronisation of the option is either done or not done in both directions.
Moreover, receivers of a config value need to check if a key can be synced because some settings
(e.g. Avatar path) could otherwise lead to exfiltration of files from a receiver's device if we
assume an attacker to have control of a device in a multi-device setting or if multiple users are
sharing an account.
- Don't sync `SyncMsgs` itself.
If a message is encrypted, but unsigned:
- Don't set `MimeMessage::from_is_signed`.
- Remove "secure-join-fingerprint" and "chat-verified" headers from `MimeMessage`.
- Minor: Preserve "Subject" from the unencrypted top level if there's no "Subject" in the encrypted
part, this message is displayed w/o a padlock anyway.
Apparently it didn't lead to any vulnerabilities because there are checks for
`MimeMessage::signatures.is_empty()` in all necessary places, but still the code looked dangerous,
especially because `from_is_singed` var name didn't correspond to its actual value (it was rather
`from_is_encrypted_maybe_signed`).
Limit the number of IMAP connections to 1 per minute regardless of the reason of reconnection, but
allow one immediate retry. This is more reliable than ratelimiting only in error conditions because
ratelimiting can't be skipped by mistake. Anyway connections shouldn't be frequent in normal
operation mode.
