diff options
| -rw-r--r-- | talpid-core/src/offline/macos.rs | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/talpid-core/src/offline/macos.rs b/talpid-core/src/offline/macos.rs index 46329f5585..8ba649856a 100644 --- a/talpid-core/src/offline/macos.rs +++ b/talpid-core/src/offline/macos.rs @@ -1,3 +1,25 @@ +//! This module has been reimplemented multiple times, often to no avail, with main issues being +//! that the app gets stuck in an offline state, blocking all internet access and preventing the +//! user from connecting to a relay. +//! +//! Currently, this functionality is implemented by using `route monitor -n` to observe routing +//! table changes and then use the CLI once more to query if there exists a default route. +//! Generally, it is assumed that a machine is online if there exists a route to a public IP +//! address that isn't using a tunnel adapter. On macOS, there were various ways of deducing this: +//! - watching the `State:/Network/Global/IPv4` key in SystemConfiguration via +//! `system-configuration-rs`, relying on a CoreFoundation runloop to drive callbacks. +//! The issue with this is that sometimes during early boot or after a re-install, the callbacks +//! won't be called, often leaving the daemon stuck in an offline state. +//! - setting a callback via [`SCNetworkReachability`]. The callback should be called whenever the +//! reachability of a remote host changes, but sometimes the callbacks just don't get called. +//! - [`NWPathMonitor`] is a macOS native interface to watch changes in the routing table. It works +//! great, but it seems to deliver updates before they actually get added to the routing table, +//! effectively calling our callbacks with routes that aren't yet usable, so starting tunnels +//! would fail anyway. This would be the API to use if we were able to bind the sockets our tunnel +//! implementations would use, but that is far too much complexity. +//! +//! [`SCNetworkReachability`]: https://developer.apple.com/documentation/systemconfiguration/scnetworkreachability-g7d +//! [`NWPathMonitor`]: https://developer.apple.com/documentation/network/nwpathmonitor use futures::{channel::mpsc::UnboundedSender, Future, StreamExt}; use std::sync::{Arc, Weak}; use talpid_types::ErrorExt; |