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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
// 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 hostinet
import (
"golang.org/x/sys/unix"
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/fdnotifier"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/fsimpl/sockfs"
"gvisor.dev/gvisor/pkg/sentry/hostfd"
"gvisor.dev/gvisor/pkg/sentry/kernel"
"gvisor.dev/gvisor/pkg/sentry/socket"
"gvisor.dev/gvisor/pkg/sentry/vfs"
"gvisor.dev/gvisor/pkg/syserr"
"gvisor.dev/gvisor/pkg/syserror"
"gvisor.dev/gvisor/pkg/usermem"
"gvisor.dev/gvisor/pkg/waiter"
)
// +stateify savable
type socketVFS2 struct {
vfsfd vfs.FileDescription
vfs.FileDescriptionDefaultImpl
vfs.LockFD
// We store metadata for hostinet sockets internally. Technically, we should
// access metadata (e.g. through stat, chmod) on the host for correctness,
// but this is not very useful for inet socket fds, which do not belong to a
// concrete file anyway.
vfs.DentryMetadataFileDescriptionImpl
socketOpsCommon
}
var _ = socket.SocketVFS2(&socketVFS2{})
func newVFS2Socket(t *kernel.Task, family int, stype linux.SockType, protocol int, fd int, flags uint32) (*vfs.FileDescription, *syserr.Error) {
mnt := t.Kernel().SocketMount()
d := sockfs.NewDentry(t, mnt)
defer d.DecRef(t)
s := &socketVFS2{
socketOpsCommon: socketOpsCommon{
family: family,
stype: stype,
protocol: protocol,
fd: fd,
},
}
s.LockFD.Init(&vfs.FileLocks{})
if err := fdnotifier.AddFD(int32(fd), &s.queue); err != nil {
return nil, syserr.FromError(err)
}
vfsfd := &s.vfsfd
if err := vfsfd.Init(s, linux.O_RDWR|(flags&linux.O_NONBLOCK), mnt, d, &vfs.FileDescriptionOptions{
DenyPRead: true,
DenyPWrite: true,
UseDentryMetadata: true,
}); err != nil {
fdnotifier.RemoveFD(int32(s.fd))
return nil, syserr.FromError(err)
}
return vfsfd, nil
}
// Release implements vfs.FileDescriptionImpl.Release.
func (s *socketVFS2) Release(ctx context.Context) {
kernel.KernelFromContext(ctx).DeleteSocketVFS2(&s.vfsfd)
s.socketOpsCommon.Release(ctx)
}
// Readiness implements waiter.Waitable.Readiness.
func (s *socketVFS2) Readiness(mask waiter.EventMask) waiter.EventMask {
return s.socketOpsCommon.Readiness(mask)
}
// EventRegister implements waiter.Waitable.EventRegister.
func (s *socketVFS2) EventRegister(e *waiter.Entry, mask waiter.EventMask) {
s.socketOpsCommon.EventRegister(e, mask)
}
// EventUnregister implements waiter.Waitable.EventUnregister.
func (s *socketVFS2) EventUnregister(e *waiter.Entry) {
s.socketOpsCommon.EventUnregister(e)
}
// Ioctl implements vfs.FileDescriptionImpl.
func (s *socketVFS2) Ioctl(ctx context.Context, uio usermem.IO, args arch.SyscallArguments) (uintptr, error) {
return ioctl(ctx, s.fd, uio, args)
}
// PRead implements vfs.FileDescriptionImpl.PRead.
func (s *socketVFS2) PRead(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) {
return 0, syserror.ESPIPE
}
// Read implements vfs.FileDescriptionImpl.
func (s *socketVFS2) Read(ctx context.Context, dst usermem.IOSequence, opts vfs.ReadOptions) (int64, error) {
// All flags other than RWF_NOWAIT should be ignored.
// TODO(gvisor.dev/issue/2601): Support RWF_NOWAIT.
if opts.Flags != 0 {
return 0, syserror.EOPNOTSUPP
}
reader := hostfd.GetReadWriterAt(int32(s.fd), -1, opts.Flags)
n, err := dst.CopyOutFrom(ctx, reader)
hostfd.PutReadWriterAt(reader)
return int64(n), err
}
// PWrite implements vfs.FileDescriptionImpl.
func (s *socketVFS2) PWrite(ctx context.Context, dst usermem.IOSequence, offset int64, opts vfs.WriteOptions) (int64, error) {
return 0, syserror.ESPIPE
}
// Write implements vfs.FileDescriptionImpl.
func (s *socketVFS2) Write(ctx context.Context, src usermem.IOSequence, opts vfs.WriteOptions) (int64, error) {
// All flags other than RWF_NOWAIT should be ignored.
// TODO(gvisor.dev/issue/2601): Support RWF_NOWAIT.
if opts.Flags != 0 {
return 0, syserror.EOPNOTSUPP
}
writer := hostfd.GetReadWriterAt(int32(s.fd), -1, opts.Flags)
n, err := src.CopyInTo(ctx, writer)
hostfd.PutReadWriterAt(writer)
return int64(n), err
}
type socketProviderVFS2 struct {
family int
}
// Socket implements socket.ProviderVFS2.Socket.
func (p *socketProviderVFS2) Socket(t *kernel.Task, stypeflags linux.SockType, protocol int) (*vfs.FileDescription, *syserr.Error) {
// Check that we are using the host network stack.
stack := t.NetworkContext()
if stack == nil {
return nil, nil
}
if _, ok := stack.(*Stack); !ok {
return nil, nil
}
// Only accept TCP and UDP.
stype := stypeflags & linux.SOCK_TYPE_MASK
switch stype {
case unix.SOCK_STREAM:
switch protocol {
case 0, unix.IPPROTO_TCP:
// ok
default:
return nil, nil
}
case unix.SOCK_DGRAM:
switch protocol {
case 0, unix.IPPROTO_UDP:
// ok
default:
return nil, nil
}
default:
return nil, nil
}
// Conservatively ignore all flags specified by the application and add
// SOCK_NONBLOCK since socketOperations requires it. Pass a protocol of 0
// to simplify the syscall filters, since 0 and IPPROTO_* are equivalent.
fd, err := unix.Socket(p.family, int(stype)|unix.SOCK_NONBLOCK|unix.SOCK_CLOEXEC, 0)
if err != nil {
return nil, syserr.FromError(err)
}
return newVFS2Socket(t, p.family, stype, protocol, fd, uint32(stypeflags&unix.SOCK_NONBLOCK))
}
// Pair implements socket.Provider.Pair.
func (p *socketProviderVFS2) Pair(t *kernel.Task, stype linux.SockType, protocol int) (*vfs.FileDescription, *vfs.FileDescription, *syserr.Error) {
// Not supported by AF_INET/AF_INET6.
return nil, nil, nil
}
|
