// Copyright 2012 The Go Authors. All rights reserved.
|
// Use of this source code is governed by a BSD-style
|
// license that can be found in the LICENSE file.
|
|
// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
|
|
package ipv4
|
|
import (
|
"unsafe"
|
|
"golang.org/x/net/internal/iana"
|
"golang.org/x/net/internal/socket"
|
)
|
|
func setControlMessage(c *socket.Conn, opt *rawOpt, cf ControlFlags, on bool) error {
|
opt.Lock()
|
defer opt.Unlock()
|
if so, ok := sockOpts[ssoReceiveTTL]; ok && cf&FlagTTL != 0 {
|
if err := so.SetInt(c, boolint(on)); err != nil {
|
return err
|
}
|
if on {
|
opt.set(FlagTTL)
|
} else {
|
opt.clear(FlagTTL)
|
}
|
}
|
if so, ok := sockOpts[ssoPacketInfo]; ok {
|
if cf&(FlagSrc|FlagDst|FlagInterface) != 0 {
|
if err := so.SetInt(c, boolint(on)); err != nil {
|
return err
|
}
|
if on {
|
opt.set(cf & (FlagSrc | FlagDst | FlagInterface))
|
} else {
|
opt.clear(cf & (FlagSrc | FlagDst | FlagInterface))
|
}
|
}
|
} else {
|
if so, ok := sockOpts[ssoReceiveDst]; ok && cf&FlagDst != 0 {
|
if err := so.SetInt(c, boolint(on)); err != nil {
|
return err
|
}
|
if on {
|
opt.set(FlagDst)
|
} else {
|
opt.clear(FlagDst)
|
}
|
}
|
if so, ok := sockOpts[ssoReceiveInterface]; ok && cf&FlagInterface != 0 {
|
if err := so.SetInt(c, boolint(on)); err != nil {
|
return err
|
}
|
if on {
|
opt.set(FlagInterface)
|
} else {
|
opt.clear(FlagInterface)
|
}
|
}
|
}
|
return nil
|
}
|
|
func marshalTTL(b []byte, cm *ControlMessage) []byte {
|
m := socket.ControlMessage(b)
|
m.MarshalHeader(iana.ProtocolIP, sysIP_RECVTTL, 1)
|
return m.Next(1)
|
}
|
|
func parseTTL(cm *ControlMessage, b []byte) {
|
cm.TTL = int(*(*byte)(unsafe.Pointer(&b[:1][0])))
|
}
|
