Use smaller and safer EC keys, replacing 2048 bit RSA.
NID_X9_62_prime256v1 is roughly as secure as a 3072 bit RSA key, but way shorter.
Since we have to embed the key in the identity packet that is sent over UDP and
some stacks aren't happy with large UDP messages (notably: macos), I switched to
EC instead of to a longer RSA key.
This seems to be compatible with other clients even on older systems like Android 5.0.
I did stick with NID_X9_62_prime256v1 because stronger EC like NID_secp384r1 failed
the handshake (I didn't investigate why).
We now store the kind of key in the config, so we can know which kind of key we are loading.
Now that devices can potentially be connected via both network and bluetooth simultaneously we should prioritise connections over the highest performing link (probably wifi/network). To this end the
m_deviceLinks are now sorted based on priority with the fastest links first; this means that when Device::sendPacket is scheduling to send a packet, it should always use the fastest link first.
The device ID is sanitized to make it safe for D-Bus, so the device ID
stored in the certificate as the subject name also needs to be
sanitized before comparison.
We operate on a QSharedData object and thus can trivially make a copy. We generally don't use use const refs as return values in KDE APIs unless there is a compelling reason to do so
KDNSSD only works with Avahi (so, only on Linux) while mdns.h is a
header-only library [1] that implements mdns from scratch and should
work on all platforms.
[1] https://github.com/mjansson/mdns
We can always provide a function rather than a value.
This is what we do in most places already and is consistent with the
rest of KDE.
This gets compiled to the same code.
```cpp
explicit QLoggingCategoryMacroHolder(const QLoggingCategory &cat)
{
if (IsOutputEnabled)
init(cat);
}
explicit QLoggingCategoryMacroHolder(QMessageLogger::CategoryFunction catfunc)
{
if (IsOutputEnabled)
init(catfunc());
}
```
By commenting out the parameter name, we get compile-time checks
Also, we can omit them for slots and Qt will not forward the parameters.
In case we had TODOs next to the code, I kept the Q_UNUSED statements
for now.
Overriding and defaulting them in the header doesn't make sense
For the dbus interfaces, we don't have any reasources to clean up or memory to be released. Meaning we can drop those lines too
- Using QLatin1String when concatinating strings is faster, because they
are more lightweight. For the resulting string, we need to allocate
new memory anyway
- Use QLatin1String overloads where they are provided by Qt APIs
- Just use const char* for log messages, the quoting of QStrings is not
needed
- Make sure to reuse string results when possible
- We do not need the return type. If a plugin declares it can handle the
packet it should do so. We don't have any fallback logic in place and
the packet types are namespaced with the plugin IDs anyway.
- Provide a default implementation with a warning, not all plugins need
to overwrite this
