github.com/sagernet/gvisor@v0.0.0-20240428053021-e691de28565f/pkg/tcpip/transport/icmp/endpoint_state.go (about)

     1  // Copyright 2018 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package icmp
    16  
    17  import (
    18  	"context"
    19  	"fmt"
    20  	"time"
    21  
    22  	"github.com/sagernet/gvisor/pkg/tcpip"
    23  	"github.com/sagernet/gvisor/pkg/tcpip/stack"
    24  	"github.com/sagernet/gvisor/pkg/tcpip/transport"
    25  )
    26  
    27  // saveReceivedAt is invoked by stateify.
    28  func (p *icmpPacket) saveReceivedAt() int64 {
    29  	return p.receivedAt.UnixNano()
    30  }
    31  
    32  // loadReceivedAt is invoked by stateify.
    33  func (p *icmpPacket) loadReceivedAt(_ context.Context, nsec int64) {
    34  	p.receivedAt = time.Unix(0, nsec)
    35  }
    36  
    37  // afterLoad is invoked by stateify.
    38  func (e *endpoint) afterLoad(ctx context.Context) {
    39  	stack.RestoreStackFromContext(ctx).RegisterRestoredEndpoint(e)
    40  }
    41  
    42  // beforeSave is invoked by stateify.
    43  func (e *endpoint) beforeSave() {
    44  	e.freeze()
    45  	e.stack.RegisterResumableEndpoint(e)
    46  }
    47  
    48  // Restore implements tcpip.RestoredEndpoint.Restore.
    49  func (e *endpoint) Restore(s *stack.Stack) {
    50  	e.thaw()
    51  
    52  	e.net.Resume(s)
    53  
    54  	e.stack = s
    55  	e.ops.InitHandler(e, e.stack, tcpip.GetStackSendBufferLimits, tcpip.GetStackReceiveBufferLimits)
    56  
    57  	switch state := e.net.State(); state {
    58  	case transport.DatagramEndpointStateInitial, transport.DatagramEndpointStateClosed:
    59  	case transport.DatagramEndpointStateBound, transport.DatagramEndpointStateConnected:
    60  		var err tcpip.Error
    61  		info := e.net.Info()
    62  		info.ID.LocalPort = e.ident
    63  		info.ID, err = e.registerWithStack(info.NetProto, info.ID)
    64  		if err != nil {
    65  			panic(fmt.Sprintf("e.registerWithStack(%d, %#v): %s", info.NetProto, info.ID, err))
    66  		}
    67  		e.ident = info.ID.LocalPort
    68  	default:
    69  		panic(fmt.Sprintf("unhandled state = %s", state))
    70  	}
    71  }
    72  
    73  // Resume implements tcpip.ResumableEndpoint.Resume.
    74  func (e *endpoint) Resume() {
    75  	e.thaw()
    76  }