117 lines
3.6 KiB
Go
117 lines
3.6 KiB
Go
// Copyright 2018 The gVisor Authors.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package udp
|
|
|
|
import (
|
|
"gvisor.dev/gvisor/pkg/tcpip"
|
|
"gvisor.dev/gvisor/pkg/tcpip/buffer"
|
|
"gvisor.dev/gvisor/pkg/tcpip/header"
|
|
"gvisor.dev/gvisor/pkg/tcpip/stack"
|
|
)
|
|
|
|
// saveData saves udpPacket.data field.
|
|
func (u *udpPacket) saveData() buffer.VectorisedView {
|
|
// We cannot save u.data directly as u.data.views may alias to u.views,
|
|
// which is not allowed by state framework (in-struct pointer).
|
|
return u.data.Clone(nil)
|
|
}
|
|
|
|
// loadData loads udpPacket.data field.
|
|
func (u *udpPacket) loadData(data buffer.VectorisedView) {
|
|
// NOTE: We cannot do the u.data = data.Clone(u.views[:]) optimization
|
|
// here because data.views is not guaranteed to be loaded by now. Plus,
|
|
// data.views will be allocated anyway so there really is little point
|
|
// of utilizing u.views for data.views.
|
|
u.data = data
|
|
}
|
|
|
|
// beforeSave is invoked by stateify.
|
|
func (e *endpoint) beforeSave() {
|
|
// Stop incoming packets from being handled (and mutate endpoint state).
|
|
// The lock will be released after savercvBufSizeMax(), which would have
|
|
// saved e.rcvBufSizeMax and set it to 0 to continue blocking incoming
|
|
// packets.
|
|
e.rcvMu.Lock()
|
|
}
|
|
|
|
// saveRcvBufSizeMax is invoked by stateify.
|
|
func (e *endpoint) saveRcvBufSizeMax() int {
|
|
max := e.rcvBufSizeMax
|
|
// Make sure no new packets will be handled regardless of the lock.
|
|
e.rcvBufSizeMax = 0
|
|
// Release the lock acquired in beforeSave() so regular endpoint closing
|
|
// logic can proceed after save.
|
|
e.rcvMu.Unlock()
|
|
return max
|
|
}
|
|
|
|
// loadRcvBufSizeMax is invoked by stateify.
|
|
func (e *endpoint) loadRcvBufSizeMax(max int) {
|
|
e.rcvBufSizeMax = max
|
|
}
|
|
|
|
// afterLoad is invoked by stateify.
|
|
func (e *endpoint) afterLoad() {
|
|
stack.StackFromEnv.RegisterRestoredEndpoint(e)
|
|
}
|
|
|
|
// Resume implements tcpip.ResumableEndpoint.Resume.
|
|
func (e *endpoint) Resume(s *stack.Stack) {
|
|
e.stack = s
|
|
|
|
for _, m := range e.multicastMemberships {
|
|
if err := e.stack.JoinGroup(e.NetProto, m.nicID, m.multicastAddr); err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
if e.state != StateBound && e.state != StateConnected {
|
|
return
|
|
}
|
|
|
|
netProto := e.effectiveNetProtos[0]
|
|
// Connect() and bindLocked() both assert
|
|
//
|
|
// netProto == header.IPv6ProtocolNumber
|
|
//
|
|
// before creating a multi-entry effectiveNetProtos.
|
|
if len(e.effectiveNetProtos) > 1 {
|
|
netProto = header.IPv6ProtocolNumber
|
|
}
|
|
|
|
var err *tcpip.Error
|
|
if e.state == StateConnected {
|
|
e.route, err = e.stack.FindRoute(e.RegisterNICID, e.ID.LocalAddress, e.ID.RemoteAddress, netProto, e.multicastLoop)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
} else if len(e.ID.LocalAddress) != 0 && !isBroadcastOrMulticast(e.ID.LocalAddress) { // stateBound
|
|
// A local unicast address is specified, verify that it's valid.
|
|
if e.stack.CheckLocalAddress(e.RegisterNICID, netProto, e.ID.LocalAddress) == 0 {
|
|
panic(tcpip.ErrBadLocalAddress)
|
|
}
|
|
}
|
|
|
|
// Our saved state had a port, but we don't actually have a
|
|
// reservation. We need to remove the port from our state, but still
|
|
// pass it to the reservation machinery.
|
|
id := e.ID
|
|
e.ID.LocalPort = 0
|
|
e.ID, err = e.registerWithStack(e.RegisterNICID, e.effectiveNetProtos, id)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
}
|