1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130
|
// Copyright 2020 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 gofer
import (
"golang.org/x/sys/unix"
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/log"
"gvisor.dev/gvisor/pkg/sentry/socket/unix/transport"
"gvisor.dev/gvisor/pkg/syserr"
"gvisor.dev/gvisor/pkg/waiter"
)
func (d *dentry) isSocket() bool {
return d.fileType() == linux.S_IFSOCK
}
func isSocketTypeSupported(sockType linux.SockType) bool {
switch sockType {
case unix.SOCK_STREAM, unix.SOCK_DGRAM, unix.SOCK_SEQPACKET:
return true
default:
return false
}
}
// endpoint is a Gofer-backed transport.BoundEndpoint.
//
// An endpoint's lifetime is the time between when filesystem.BoundEndpointAt()
// is called and either BoundEndpoint.BidirectionalConnect or
// BoundEndpoint.UnidirectionalConnect is called.
//
// +stateify savable
type endpoint struct {
// dentry is the filesystem dentry which produced this endpoint. dentry is
// not synthetic.
dentry *dentry
// path is the sentry path where this endpoint is bound.
path string
}
// BidirectionalConnect implements BoundEndpoint.BidirectionalConnect.
func (e *endpoint) BidirectionalConnect(ctx context.Context, ce transport.ConnectingEndpoint, returnConnect func(transport.Receiver, transport.ConnectedEndpoint)) *syserr.Error {
// No lock ordering required as only the ConnectingEndpoint has a mutex.
ce.Lock()
// Check connecting state.
if ce.Connected() {
ce.Unlock()
return syserr.ErrAlreadyConnected
}
if ce.ListeningLocked() {
ce.Unlock()
return syserr.ErrInvalidEndpointState
}
c, err := e.newConnectedEndpoint(ctx, ce.Type(), ce.WaiterQueue())
if err != nil {
ce.Unlock()
return err
}
returnConnect(c, c)
ce.Unlock()
if err := c.Init(); err != nil {
return syserr.FromError(err)
}
return nil
}
// UnidirectionalConnect implements
// transport.BoundEndpoint.UnidirectionalConnect.
func (e *endpoint) UnidirectionalConnect(ctx context.Context) (transport.ConnectedEndpoint, *syserr.Error) {
c, err := e.newConnectedEndpoint(ctx, linux.SOCK_DGRAM, &waiter.Queue{})
if err != nil {
return nil, err
}
if err := c.Init(); err != nil {
return nil, syserr.FromError(err)
}
// We don't need the receiver.
c.CloseRecv()
c.Release(ctx)
return c, nil
}
func (e *endpoint) newConnectedEndpoint(ctx context.Context, sockType linux.SockType, queue *waiter.Queue) (*transport.SCMConnectedEndpoint, *syserr.Error) {
e.dentry.fs.renameMu.RLock()
hostSockFD, err := e.dentry.connect(ctx, sockType)
e.dentry.fs.renameMu.RUnlock()
if err != nil {
return nil, syserr.ErrConnectionRefused
}
c, serr := transport.NewSCMEndpoint(hostSockFD, queue, e.path)
if serr != nil {
unix.Close(hostSockFD)
log.Warningf("NewSCMEndpoint failed: path=%q, err=%v", e.path, serr)
return nil, serr
}
return c, nil
}
// Release implements transport.BoundEndpoint.Release.
func (e *endpoint) Release(ctx context.Context) {
e.dentry.DecRef(ctx)
}
// Passcred implements transport.BoundEndpoint.Passcred.
func (e *endpoint) Passcred() bool {
return false
}
|