This change adds support for receiving
Autocrypt header in the protected part of encrypted message.
Autocrypt header is now also allowed in mailing lists.
Previously Autocrypt header was rejected when
List-Post header was present,
but the check for the address being equal to the From: address
is sufficient.
New experimental `protect_autocrypt` config is disabled
by default because Delta Chat with reception
support should be released first on all platforms.
When doing an AEAP transition, we mustn't just delete the old peerstate as this would break
encryption to it. This is critical for non-verified groups -- if we can't encrypt to the old
address, we can't securely remove it from the group (to add the new one instead).
`a.clone_from(&b)` is equivalent to `a = b.clone()` in functionality,
but can be overridden to reuse the resources of a to avoid unnecessary
allocations.
An unencrypted message with already known Autocrypt key, but sent from another address, means that
it's rather a new contact sharing the same key than the existing one changed its address, otherwise
it would already have our key to encrypt.
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`).
When a key is gossiped for the contact in a verified chat,
it is stored in the secondary verified key slot.
The messages are then encrypted to the secondary verified key
if they are also encrypted to the contact introducing this secondary key.
Chat-Group-Member-Added no longer updates the verified key.
Verified group recovery only relies on the secondary verified key.
When a message is received from a contact
signed with a secondary verified key,
secondary verified key replaces the primary verified key.
When verified key is changed for the contact
in response to receiving a message
signed with a secondary verified key,
"Setup changed" message is added
to the same chat where the message is received.
Moved custom ToSql trait including Send + Sync from lib.rs to sql.rs.
Replaced most params! and paramsv! macro usage with tuples.
Replaced paramsv! and params_iterv! with params_slice!,
because there is no need to construct a vector.
.call() interface is safer because it ensures
that blocking operations on SQL connection
are called within tokio::task::block_in_place().
Previously some code called blocking operations
in async context, e.g. add_parts() in receive_imf module.
The underlying implementation of .call()
can later be replaced with an implementation
that does not require block_in_place(),
e.g. a worker pool,
without changing the code using the .call() interface.
Derive Debug, PartialEq and Eq for Peerstate,
so `verifier` is included in Debug output and compared.
Store verifier as empty string
instead of NULL in the database.
- Return Result from set_verified() so that it can't be missed.
- Pass Fingerprint to set_verified() by value to avoid cloning it inside. This optimises out an
extra clone() if we already have a value that can be moved at the caller side. However, this may
add an extra clone() if set_verified() fails, but let's not optimise the fail scenario.
This allows to distinguish exceptions,
such as database errors, from invalid user input.
For example, if the From: field of the message
does not look like an email address, the mail
should be ignored. But if there is a database
failure while writing a new contact for the address,
this error should be bubbled up.
Note that if the message is encrypted, we don't check whether it's signed with an attached key
currently, otherwise a massive refactoring of the code is needed because for encrypted messages a
signature is checked and discarded first now.
This esp. speeds up receive_imf a bit when we recreate the member list (recreate_member_list == true).
It's a preparation for https://github.com/deltachat/deltachat-core-rust/issues/3768, which will be a one-line-fix, but recreate the member list more often, so that we want to optimize this case a bit.
It also adds a benchmark for this case. It's not that easy to make the benchmark non-flaky, but by closing all other programs and locking the CPU to 1.5GHz it worked. It is consistently a few percent faster than ./without-optim:
```
Receive messages/Receive 100 Chat-Group-Member-{Added|Removed} messages
time: [52.257 ms 52.569 ms 52.941 ms]
change: [-3.5301% -2.6181% -1.6697%] (p = 0.00 < 0.05)
Performance has improved.
Found 7 outliers among 100 measurements (7.00%)
4 (4.00%) high mild
3 (3.00%) high severe
```
