40 lines
1.2 KiB
Go
40 lines
1.2 KiB
Go
//go:build linux
|
|
|
|
package quic
|
|
|
|
import (
|
|
"errors"
|
|
"syscall"
|
|
|
|
"github.com/lucas-clemente/quic-go/internal/utils"
|
|
"golang.org/x/sys/unix"
|
|
)
|
|
|
|
func setDF(rawConn syscall.RawConn) error {
|
|
// Enabling IP_MTU_DISCOVER will force the kernel to return "sendto: message too long"
|
|
// and the datagram will not be fragmented
|
|
var errDFIPv4, errDFIPv6 error
|
|
if err := rawConn.Control(func(fd uintptr) {
|
|
errDFIPv4 = unix.SetsockoptInt(int(fd), unix.IPPROTO_IP, unix.IP_MTU_DISCOVER, unix.IP_PMTUDISC_DO)
|
|
errDFIPv6 = unix.SetsockoptInt(int(fd), unix.IPPROTO_IPV6, unix.IPV6_MTU_DISCOVER, unix.IPV6_PMTUDISC_DO)
|
|
}); err != nil {
|
|
return err
|
|
}
|
|
switch {
|
|
case errDFIPv4 == nil && errDFIPv6 == nil:
|
|
utils.DefaultLogger.Debugf("Setting DF for IPv4 and IPv6.")
|
|
case errDFIPv4 == nil && errDFIPv6 != nil:
|
|
utils.DefaultLogger.Debugf("Setting DF for IPv4.")
|
|
case errDFIPv4 != nil && errDFIPv6 == nil:
|
|
utils.DefaultLogger.Debugf("Setting DF for IPv6.")
|
|
case errDFIPv4 != nil && errDFIPv6 != nil:
|
|
return errors.New("setting DF failed for both IPv4 and IPv6")
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func isMsgSizeErr(err error) bool {
|
|
// https://man7.org/linux/man-pages/man7/udp.7.html
|
|
return errors.Is(err, unix.EMSGSIZE)
|
|
}
|