- Support for multiple listeners (although currently only TCP listeners are supported)
- New multicast behaviour where each multicast interface is given it's own link-local listener and does not depend on the `Listen` configuration
- Blocking detection in the switch to avoid parenting a blocked peer
- Support for adding and removing listeners and multicast interfaces when reloading configuration during runtime
- Yggdrasil will now attempt to clean up UNIX admin sockets on startup if left behind by a previous crash
- Admin socket `getTunnelRouting` and `setTunnelRouting` calls for enabling and disabling crypto-key routing during runtime
- On macOS, Yggdrasil will now try to wake up AWDL on start-up when `awdl0` is a configured multicast interface
### Changed
- The `Listen` configuration statement is now an array instead of a string
- The `Listen` configuration statement should now conform to the same formatting as peers with the protocol prefix, e.g. `tcp://[::]:0`
- Session workers are now non-blocking
- Multicast interval is now fixed at every 15 seconds and network interfaces are reevaluated for eligibility on each interval (where before the interval depended upon the number of configured multicast interfaces and evaluation only took place at startup)
- Dead connections are now closed in the link handler as opposed to the switch
- Peer forwarding is now prioritised instead of randomised
### Fixed
- Admin socket `getTunTap` call now returns properly instead of claiming no interface is enabled in all cases
- Handling of `getRoutes` etc in `yggdrasilctl` is now working
- Local interface names are no longer leaked in multicast packets
- Link-local TCP connections, particularly those initiated because of multicast beacons, are now always correctly scoped for the target interface
- Yggdrasil now correctly responds to multicast interfaces going up and down during runtime
- Dynamic reconfiguration, which allows reloading the configuration file to make changes during runtime by sending a `SIGHUP` signal (note: this only works with `-useconffile` and not `-useconf` and currently reconfiguring TUN/TAP is not supported)
- Support for building Yggdrasil as an iOS or Android framework if the appropriate tools (e.g. `gomobile`/`gobind` + SDKs) are available
- Connection contexts used for TCP connections which allow more exotic socket options to be set, e.g.
- Reusing the multicast socket to allow multiple running Yggdrasil instances without having to disable multicast
- Allowing supported Macs to peer with other nearby Macs that aren't even on the same Wi-Fi network using AWDL
- Flexible logging support, which allows for logging at different levels of verbosity
### Changed
- Switch changes to improve parent selection
- Node configuration is now stored centrally, rather than having fragments/copies distributed at startup time
- Significant refactoring in various areas, including for link types (TCP, AWDL etc), generic streams and adapters
- macOS builds through CircleCI are now 64-bit only
- The admin socket is now multithreaded, greatly improving performance of the crawler and allowing concurrent lookups to take place
- The ability to hide NodeInfo defaults through either setting the `NodeInfoPrivacy` option or through setting individual `NodeInfo` attributes to `null`
### Changed
- The `armhf` build now targets ARMv6 instead of ARMv7, adding support for Raspberry Pi Zero and other older models, amongst others
### Fixed
- DHT entries are now populated using a copy in memory to fix various potential DHT bugs
- DHT traffic should now throttle back exponentially to reduce idle traffic
- Adjust how nodes are inserted into the DHT which should help to reduce some incorrect DHT traffic
- In TAP mode, the NDP target address is now correctly used when populating the peer MAC table. This fixes serious connectivity problems when in TAP mode, particularly on BSD
- In TUN mode, ICMPv6 packets are now ignored whereas they were incorrectly processed before
- The address range was moved from `fd00::/8` to `200::/7`. This range was chosen as it is marked as deprecated. The change prevents overlap with other ULA privately assigned ranges.
- UTF-16 detection conversion for configuration files, which can particularly be a problem on Windows 10 if a configuration file is generated from within PowerShell.
- Exchange version information during connection setup, to prevent connections with incompatible versions.
### Changed
- Wire format changes (backwards incompatible).
- Less maintenance traffic per peer.
- Exponential back-off for DHT maintenance traffic (less maintenance traffic for known good peers).
- Iterative DHT (added some time between v0.1.0 and here).
- Use local queue sizes for a sort of local-only backpressure routing, instead of the removed bandwidth estimates, when deciding where to send a packet.
### Removed
- UDP peering, this may be added again if/when a better implementation appears.