mqtt/server/listeners/tcp.go
Кобелев Андрей Андреевич 4ea1a3802b clone
2022-08-15 23:06:20 +03:00

128 lines
3.0 KiB
Go

package listeners
import (
"crypto/tls"
"net"
"sync"
"sync/atomic"
"github.com/mochi-co/mqtt/server/listeners/auth"
"github.com/mochi-co/mqtt/server/system"
)
// TCP is a listener for establishing client connections on basic TCP protocol.
type TCP struct {
sync.RWMutex
id string // the internal id of the listener.
protocol string // the TCP protocol to use.
address string // the network address to bind to.
listen net.Listener // a net.Listener which will listen for new clients.
config *Config // configuration values for the listener.
end uint32 // ensure the close methods are only called once.
}
// NewTCP initialises and returns a new TCP listener, listening on an address.
func NewTCP(id, address string) *TCP {
return &TCP{
id: id,
protocol: "tcp",
address: address,
config: &Config{ // default configuration.
Auth: new(auth.Allow),
TLS: new(TLS),
},
}
}
// SetConfig sets the configuration values for the listener config.
func (l *TCP) SetConfig(config *Config) {
l.Lock()
if config != nil {
l.config = config
// If a config has been passed without an auth controller,
// it may be a mistake, so disallow all traffic.
if l.config.Auth == nil {
l.config.Auth = new(auth.Disallow)
}
}
l.Unlock()
}
// ID returns the id of the listener.
func (l *TCP) ID() string {
l.RLock()
id := l.id
l.RUnlock()
return id
}
// Listen starts listening on the listener's network address.
func (l *TCP) Listen(s *system.Info) error {
var err error
// The following logic is deprecated in favour of passing through the tls.Config
// value directly, however it remains in order to provide backwards compatibility.
// It will be removed someday, so use the preferred method (l.config.TLSConfig).
if l.config.TLS != nil && len(l.config.TLS.Certificate) > 0 && len(l.config.TLS.PrivateKey) > 0 {
var cert tls.Certificate
cert, err = tls.X509KeyPair(l.config.TLS.Certificate, l.config.TLS.PrivateKey)
if err != nil {
return err
}
l.listen, err = tls.Listen(l.protocol, l.address, &tls.Config{
Certificates: []tls.Certificate{cert},
})
} else if l.config.TLSConfig != nil {
l.listen, err = tls.Listen(l.protocol, l.address, l.config.TLSConfig)
} else {
l.listen, err = net.Listen(l.protocol, l.address)
}
if err != nil {
return err
}
return nil
}
// Serve starts waiting for new TCP connections, and calls the establish
// connection callback for any received.
func (l *TCP) Serve(establish EstablishFunc) {
for {
if atomic.LoadUint32(&l.end) == 1 {
return
}
conn, err := l.listen.Accept()
if err != nil {
return
}
if atomic.LoadUint32(&l.end) == 0 {
go func() {
_ = establish(l.id, conn, l.config.Auth)
}()
}
}
}
// Close closes the listener and any client connections.
func (l *TCP) Close(closeClients CloseFunc) {
l.Lock()
defer l.Unlock()
if atomic.CompareAndSwapUint32(&l.end, 0, 1) {
closeClients(l.id)
}
if l.listen != nil {
err := l.listen.Close()
if err != nil {
return
}
}
}