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
|
// Copyright 2018 Google LLC
//
// 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 epsocket
import (
"syscall"
"gvisor.googlesource.com/gvisor/pkg/abi/linux"
"gvisor.googlesource.com/gvisor/pkg/sentry/context"
"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
"gvisor.googlesource.com/gvisor/pkg/sentry/kernel"
"gvisor.googlesource.com/gvisor/pkg/sentry/kernel/auth"
"gvisor.googlesource.com/gvisor/pkg/sentry/socket"
"gvisor.googlesource.com/gvisor/pkg/sentry/socket/unix/transport"
"gvisor.googlesource.com/gvisor/pkg/syserr"
"gvisor.googlesource.com/gvisor/pkg/tcpip"
"gvisor.googlesource.com/gvisor/pkg/tcpip/header"
"gvisor.googlesource.com/gvisor/pkg/tcpip/network/ipv4"
"gvisor.googlesource.com/gvisor/pkg/tcpip/network/ipv6"
"gvisor.googlesource.com/gvisor/pkg/tcpip/transport/tcp"
"gvisor.googlesource.com/gvisor/pkg/tcpip/transport/udp"
"gvisor.googlesource.com/gvisor/pkg/waiter"
)
// provider is an inet socket provider.
type provider struct {
family int
netProto tcpip.NetworkProtocolNumber
}
// getTransportProtocol figures out transport protocol. Currently only TCP,
// UDP, and ICMP are supported.
func getTransportProtocol(ctx context.Context, stype transport.SockType, protocol int) (tcpip.TransportProtocolNumber, *syserr.Error) {
switch stype {
case linux.SOCK_STREAM:
if protocol != 0 && protocol != syscall.IPPROTO_TCP {
return 0, syserr.ErrInvalidArgument
}
return tcp.ProtocolNumber, nil
case linux.SOCK_DGRAM:
switch protocol {
case 0, syscall.IPPROTO_UDP:
return udp.ProtocolNumber, nil
case syscall.IPPROTO_ICMP:
return header.ICMPv4ProtocolNumber, nil
case syscall.IPPROTO_ICMPV6:
return header.ICMPv6ProtocolNumber, nil
}
case linux.SOCK_RAW:
// Raw sockets require CAP_NET_RAW.
creds := auth.CredentialsFromContext(ctx)
if !creds.HasCapability(linux.CAP_NET_RAW) {
return 0, syserr.ErrPermissionDenied
}
switch protocol {
case syscall.IPPROTO_ICMP:
return header.ICMPv4ProtocolNumber, nil
}
}
return 0, syserr.ErrInvalidArgument
}
// Socket creates a new socket object for the AF_INET or AF_INET6 family.
func (p *provider) Socket(t *kernel.Task, stype transport.SockType, protocol int) (*fs.File, *syserr.Error) {
// Fail right away if we don't have a stack.
stack := t.NetworkContext()
if stack == nil {
// Don't propagate an error here. Instead, allow the socket
// code to continue searching for another provider.
return nil, nil
}
eps, ok := stack.(*Stack)
if !ok {
return nil, nil
}
// Figure out the transport protocol.
transProto, err := getTransportProtocol(t, stype, protocol)
if err != nil {
return nil, err
}
// Create the endpoint.
var ep tcpip.Endpoint
var e *tcpip.Error
wq := &waiter.Queue{}
if stype == linux.SOCK_RAW {
ep, e = eps.Stack.NewRawEndpoint(transProto, p.netProto, wq)
} else {
ep, e = eps.Stack.NewEndpoint(transProto, p.netProto, wq)
}
if e != nil {
return nil, syserr.TranslateNetstackError(e)
}
return New(t, p.family, stype, wq, ep)
}
// Pair just returns nil sockets (not supported).
func (*provider) Pair(*kernel.Task, transport.SockType, int) (*fs.File, *fs.File, *syserr.Error) {
return nil, nil, nil
}
// init registers socket providers for AF_INET and AF_INET6.
func init() {
// Providers backed by netstack.
p := []provider{
{
family: linux.AF_INET,
netProto: ipv4.ProtocolNumber,
},
{
family: linux.AF_INET6,
netProto: ipv6.ProtocolNumber,
},
}
for i := range p {
socket.RegisterProvider(p[i].family, &p[i])
}
}
|
