When running `tailscale exit-node list`, an empty city or country name
should be displayed as a hyphen "-". However, this only happened when
there was no location at all. If a node provides a Hostinfo.Location,
then the list would display exactly what was provided.
This patch changes the listing so that empty cities and countries will
either render the provided name or "-".
Fixes#16500
Signed-off-by: Simon Law <sfllaw@tailscale.com>
GitHub used to recommend the tibdex/github-app-token GitHub Action
until they wrote their own actions/create-github-app-token.
This patch replaces the use of the third-party action with the
official one.
Updates #cleanup
Signed-off-by: Simon Law <sfllaw@tailscale.com>
For any changes that involve DERP, automatically add the
@tailscale/dataplane team as a reviewer.
Updates #cleanup
Signed-off-by: Simon Law <sfllaw@tailscale.com>
This patch contains the following cleanups:
1. Simplify `ffcli.Command` definitions;
2. Word-wrap help text, consistent with other commands;
3. `tailscale dns --help` usage makes subcommand usage more obvious;
4. `tailscale dns query --help` describes DNS record types.
Updates #cleanup
Signed-off-by: Simon Law <sfllaw@tailscale.com>
To authenticate mesh keys, the DERP servers used a simple == comparison,
which is susceptible to a side channel timing attack.
By extracting the mesh key for a DERP server, an attacker could DoS it
by forcing disconnects using derp.Client.ClosePeer. They could also
enumerate the public Wireguard keys, IP addresses and ports for nodes
connected to that DERP server.
DERP servers configured without mesh keys deny all such requests.
This patch also extracts the mesh key logic into key.DERPMesh, to
prevent this from happening again.
Security bulletin: https://tailscale.com/security-bulletins#ts-2025-003Fixestailscale/corp#28720
Signed-off-by: Simon Law <sfllaw@tailscale.com>
`cmd/derpprobe --once` didn’t respect the convention of non-zero exit
status for a failed run. It would always exit zero (i.e. success),
even. This patch fixes that, but only for `--once` mode.
Fixes: #15925
Signed-off-by: Simon Law <sfllaw@tailscale.com>