wireguard-go/device, branch js/sample-api

device: add Device.ListenPort and Device.SetListenPort

2020-12-22T19:29:28Z

This is a sample commit for a possible way to make a Go API that lives alongside UAPI. The general idea is to add Device and Peer methods corresponding to UAPI directives, including a way to look up a peer from a device based on a public key, as in UAPI. The UAPI code then deals with parsing and generating textual input/output, and calls the Go methods to do the work. This commit also contains a bug fix for a racy access of device.net.port I will send an independently commit that fixes those directly in UAPI. This commit is NOT meant to be merged as-is. Signed-off-by: Josh Bleecher Snyder

device: add UAPI helper methods

2020-12-22T13:30:57Z

Signed-off-by: Jason A. Donenfeld

device: add missing colon to error line

2020-12-18T19:18:47Z

People are actually hitting this condition, so make it uniform. Also, change a printf into a println, to match the other conventions. Signed-off-by: Jason A. Donenfeld

device: fix error shadowing before log print

2020-12-17T11:15:14Z

Signed-off-by: Brad Fitzpatrick

device: fix data race in peer.timersActive

2020-12-17T00:16:26Z

Found by the race detector and existing tests. To avoid introducing a lock into this hot path, calculate and cache whether any peers exist. Signed-off-by: Josh Bleecher Snyder

device: fix races from changing private_key

2020-12-17T00:16:26Z

Access keypair.sendNonce atomically. Eliminate one unnecessary initialization to zero. Mutate handshake.lastSentHandshake with the mutex held. Co-authored-by: David Anderson Signed-off-by: Josh Bleecher Snyder

device: always name QueueElement variables elem

2020-12-17T00:16:26Z

They're called elem in most places. Rename a few local variables to make it consistent. This makes it easier to grep the code for things like elem.Drop. Signed-off-by: Josh Bleecher Snyder

device: use channel close to shut down and drain outbound channel

2020-12-17T00:16:26Z

This is a similar treatment to the handling of the encryption channel found a few commits ago: Use the closing of the channel to manage goroutine lifetime and shutdown. It is considerably simpler because there is only a single writer. Signed-off-by: Josh Bleecher Snyder

device: fix persistent_keepalive_interval data races

2020-12-16T00:57:09Z

Co-authored-by: David Anderson Signed-off-by: Josh Bleecher Snyder

device: use channel close to shut down and drain encryption channel

2020-12-16T00:57:09Z

The new test introduced in this commit used to deadlock about 1% of the time. I believe that the deadlock occurs as follows: * The test completes, calling device.Close. * device.Close closes device.signals.stop. * RoutineEncryption stops. * The deferred function in RoutineEncryption drains device.queue.encryption. * RoutineEncryption exits. * A peer's RoutineNonce processes an element queued in peer.queue.nonce. * RoutineNonce puts that element into the outbound and encryption queues. * RoutineSequentialSender reads that elements from the outbound queue. * It waits for that element to get Unlocked by RoutineEncryption. * RoutineEncryption has already exited, so RoutineSequentialSender blocks forever. * device.RemoveAllPeers calls peer.Stop on all peers. * peer.Stop waits for peer.routines.stopping, which blocks forever. Rather than attempt to add even more ordering to the already complex centralized shutdown orchestration, this commit moves towards a data-flow-oriented shutdown. The device.queue.encryption gets closed when there will be no more writes to it. All device.queue.encryption readers always read until the channel is closed and then exit. We thus guarantee that any element that enters the encryption queue also exits it. This removes the need for central control of the lifetime of RoutineEncryption, removes the need to drain the encryption queue on shutdown, and simplifies RoutineEncryption. This commit also fixes a data race. When RoutineSequentialSender drains its queue on shutdown, it needs to lock the elem before operating on it, just as the main body does. The new test in this commit passed 50k iterations with the race detector enabled and 150k iterations with the race detector disabled, with no failures. Signed-off-by: Josh Bleecher Snyder

wireguard-go/device, branch js/sample-api

device: add Device.ListenPort and Device.SetListenPort

device: add UAPI helper methods

device: add missing colon to error line

device: fix error shadowing before log print

device: fix data race in peer.timersActive

device: fix races from changing private_key

device: always name *Queue*Element variables elem

device: use channel close to shut down and drain outbound channel

device: fix persistent_keepalive_interval data races

device: use channel close to shut down and drain encryption channel

device: always name QueueElement variables elem