Use buffer pools for UDP packet forwarding to prepare for increasing the
forwarded UDP packet size for peer path MTU discovery.
Updates #311
Co-authored-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Val <valerie@tailscale.com>
Prepare for path MTU discovery by splitting up the concept of
DefaultMTU() into the concepts of the Tailscale TUN MTU, MTUs of
underlying network interfaces, minimum "safe" TUN MTU, user configured
TUN MTU, probed path MTU to a peer, and maximum probed MTU. Add a set
of likely MTUs to probe.
Updates #311
Signed-off-by: Val <valerie@tailscale.com>
Use buffer pools for UDP packet forwarding to prepare for increasing the
forwarded UDP packet size for peer path MTU discovery.
Updates #311
Co-authored-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Signed-off-by: Val <valerie@tailscale.com>
Replace CanPMTUD() with ShouldPMTUD() to check if peer path MTU discovery should
be enabled, in preparation for adding support for enabling/disabling peer MTU
dynamically.
Updated #311
Signed-off-by: Val <valerie@tailscale.com>
Add an enable/disable argument to setDontFragment() in preparation for dynamic
enable/disable of peer path MTU discovery. Add getDontFragment() to get the
status of the don't fragment bit from a socket.
Updates #311
Co-authored-by: James Tucker <james@tailscale.com>
Signed-off-by: Val <valerie@tailscale.com>
Use IPV6_MTU_DISCOVER for setting don't fragment on IPv6 sockets on Linux (was
using IP_MTU_DISCOVER, the IPv4 arg).
Updates #311
Signed-off-by: Val <valerie@tailscale.com>
Make the debugknob variable name for enabling peer path MTU discovery match the
env variable name.
Updates #311
Signed-off-by: Val <valerie@tailscale.com>
When running in our github CI environment, curl sometimes hangs while closing
the download from the nodejs.org server and fails with INTERNAL_ERROR. This is
likely caused by CI running behind some kind of load balancer or proxy that
handles HTTP/2 incorrectly in some minor way, so force curl to use HTTP 1.1.
Updates #8988
Signed-off-by: Val <valerie@tailscale.com>
When sending a ping from the CLI, only accept a pong that is in reply
to the specific CLI ping we sent.
Updates #311
Signed-off-by: Val <valerie@tailscale.com>
The MacOS client can't set the MTU when creating the tun due to lack
of permissions, so add it to the router config and have MacOS set it
in the callback using a method that it does have permissions for.
Updates #8219
Signed-off-by: Val <valerie@tailscale.com>
Correct a minor cut-n-paste error that resulted in an invalid or
missing ping type being accepted as a disco ping.
Fixes#8457
Signed-off-by: Val <valerie@tailscale.com>
prober uses NewRegionClient() to connect to a derper using a faked up
single-node region, but NewRegionClient() fails to connect if there is
no non-STUN only client in the region. Set the STUN only flag to false
before we call NewRegionClient() so we can monitor nodes marked as
STUN only in the default derpmap.
Updates #11492
Signed-off-by: Val <valerie@tailscale.com>
go vet complains when we copy a lock value. Create clone function that
copies everything but the lock value.
Fixes#8207
Signed-off-by: Val <valerie@tailscale.com>
~97% of the log messages derper outputs are related to the normal
non-error state of a client disconnecting in some manner. Add a
verbose logging feature that only logs these messages when enabled.
Fixes#8024
Signed-off-by: Val <valerie@tailscale.com>
Make developing derp easier by:
1. Creating an envknob telling clients to use HTTP to connect to derp
servers, so devs don't have to acquire a valid TLS cert.
2. Creating an envknob telling clients which derp server to connect
to, so devs don't have to edit the ACLs in the admin console to add a
custom DERP map.
3. Explaining how the -dev and -a command lines args to derper
interact.
To use this:
1. Run derper with -dev.
2. Run tailscaled with TS_DEBUG_USE_DERP_HTTP=1 and
TS_DEBUG_USE_DERP_ADDR=localhost
This will result in the client connecting to derp via HTTP on port
3340.
Fixes#7700
Signed-off-by: Val <valerie@tailscale.com>