mirror of
https://github.com/tailscale/tailscale.git
synced 2024-11-30 05:25:35 +00:00
3672f29a4e
The goal is to move more network state accessors to netmon.Monitor where they can be cheaper/cached. But first (this change and others) we need to make sure the one netmon.Monitor is plumbed everywhere. Some notable bits: * tsdial.NewDialer is added, taking a now-required netmon * because a tsdial.Dialer always has a netmon, anything taking both a Dialer and a NetMon is now redundant; take only the Dialer and get the NetMon from that if/when needed. * netmon.NewStatic is added, primarily for tests Updates tailscale/corp#10910 Updates tailscale/corp#18960 Updates #7967 Updates #3299 Change-Id: I877f9cb87618c4eb037cee098241d18da9c01691 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
103 lines
2.5 KiB
Go
103 lines
2.5 KiB
Go
// Copyright (c) Tailscale Inc & AUTHORS
|
|
// SPDX-License-Identifier: BSD-3-Clause
|
|
|
|
package netcheck
|
|
|
|
import (
|
|
"context"
|
|
"errors"
|
|
"net/netip"
|
|
|
|
"tailscale.com/net/netaddr"
|
|
"tailscale.com/net/netns"
|
|
"tailscale.com/net/stun"
|
|
"tailscale.com/types/logger"
|
|
"tailscale.com/types/nettype"
|
|
"tailscale.com/util/multierr"
|
|
)
|
|
|
|
// Standalone creates the necessary UDP sockets on the given bindAddr and starts
|
|
// an IO loop so that the Client can perform active probes with no further need
|
|
// for external driving of IO (no need to set/implement SendPacket, or call
|
|
// ReceiveSTUNPacket). It must be called prior to starting any reports and is
|
|
// shut down by cancellation of the provided context. If both IPv4 and IPv6 fail
|
|
// to bind, errors will be returned, if one or both protocols can bind no error
|
|
// is returned.
|
|
func (c *Client) Standalone(ctx context.Context, bindAddr string) error {
|
|
if c.NetMon == nil {
|
|
panic("netcheck.Client.NetMon must be set")
|
|
}
|
|
if bindAddr == "" {
|
|
bindAddr = ":0"
|
|
}
|
|
var errs []error
|
|
|
|
u4, err := nettype.MakePacketListenerWithNetIP(netns.Listener(c.logf, c.NetMon)).ListenPacket(ctx, "udp4", bindAddr)
|
|
if err != nil {
|
|
c.logf("udp4: %v", err)
|
|
errs = append(errs, err)
|
|
} else {
|
|
go readPackets(ctx, c.logf, u4, c.ReceiveSTUNPacket)
|
|
}
|
|
|
|
u6, err := nettype.MakePacketListenerWithNetIP(netns.Listener(c.logf, c.NetMon)).ListenPacket(ctx, "udp6", bindAddr)
|
|
if err != nil {
|
|
c.logf("udp6: %v", err)
|
|
errs = append(errs, err)
|
|
} else {
|
|
go readPackets(ctx, c.logf, u6, c.ReceiveSTUNPacket)
|
|
}
|
|
|
|
c.SendPacket = func(pkt []byte, dst netip.AddrPort) (int, error) {
|
|
pc := u4
|
|
if dst.Addr().Is6() {
|
|
pc = u6
|
|
}
|
|
if pc == nil {
|
|
return 0, errors.New("no UDP socket")
|
|
}
|
|
|
|
return pc.WriteToUDPAddrPort(pkt, dst)
|
|
}
|
|
|
|
// If both v4 and v6 failed, report an error, otherwise let one succeed.
|
|
if len(errs) == 2 {
|
|
return multierr.New(errs...)
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// readPackets reads STUN packets from pc until there's an error or ctx is done.
|
|
// In either case, it closes pc.
|
|
func readPackets(ctx context.Context, logf logger.Logf, pc nettype.PacketConn, recv func([]byte, netip.AddrPort)) {
|
|
done := make(chan struct{})
|
|
defer close(done)
|
|
|
|
go func() {
|
|
select {
|
|
case <-ctx.Done():
|
|
case <-done:
|
|
}
|
|
pc.Close()
|
|
}()
|
|
|
|
var buf [64 << 10]byte
|
|
for {
|
|
n, addr, err := pc.ReadFromUDPAddrPort(buf[:])
|
|
if err != nil {
|
|
if ctx.Err() != nil {
|
|
return
|
|
}
|
|
logf("ReadFrom: %v", err)
|
|
return
|
|
}
|
|
pkt := buf[:n]
|
|
if !stun.Is(pkt) {
|
|
continue
|
|
}
|
|
if ap := netaddr.Unmap(addr); ap.IsValid() {
|
|
recv(pkt, ap)
|
|
}
|
|
}
|
|
}
|