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
|
// 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 tty
import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/context"
"gvisor.dev/gvisor/pkg/refs"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/kernel"
"gvisor.dev/gvisor/pkg/usermem"
)
// LINT.IfChange
// Terminal is a pseudoterminal.
//
// +stateify savable
type Terminal struct {
refs.AtomicRefCount
// n is the terminal index. It is immutable.
n uint32
// d is the containing directory. It is immutable.
d *dirInodeOperations
// ld is the line discipline of the terminal. It is immutable.
ld *lineDiscipline
// masterKTTY contains the controlling process of the master end of
// this terminal. This field is immutable.
masterKTTY *kernel.TTY
// slaveKTTY contains the controlling process of the slave end of this
// terminal. This field is immutable.
slaveKTTY *kernel.TTY
}
func newTerminal(ctx context.Context, d *dirInodeOperations, n uint32) *Terminal {
termios := linux.DefaultSlaveTermios
t := Terminal{
d: d,
n: n,
ld: newLineDiscipline(termios),
masterKTTY: &kernel.TTY{Index: n},
slaveKTTY: &kernel.TTY{Index: n},
}
t.EnableLeakCheck("tty.Terminal")
return &t
}
// setControllingTTY makes tm the controlling terminal of the calling thread
// group.
func (tm *Terminal) setControllingTTY(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) error {
task := kernel.TaskFromContext(ctx)
if task == nil {
panic("setControllingTTY must be called from a task context")
}
return task.ThreadGroup().SetControllingTTY(tm.tty(isMaster), args[2].Int())
}
// releaseControllingTTY removes tm as the controlling terminal of the calling
// thread group.
func (tm *Terminal) releaseControllingTTY(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) error {
task := kernel.TaskFromContext(ctx)
if task == nil {
panic("releaseControllingTTY must be called from a task context")
}
return task.ThreadGroup().ReleaseControllingTTY(tm.tty(isMaster))
}
// foregroundProcessGroup gets the process group ID of tm's foreground process.
func (tm *Terminal) foregroundProcessGroup(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
task := kernel.TaskFromContext(ctx)
if task == nil {
panic("foregroundProcessGroup must be called from a task context")
}
ret, err := task.ThreadGroup().ForegroundProcessGroup(tm.tty(isMaster))
if err != nil {
return 0, err
}
// Write it out to *arg.
_, err = usermem.CopyObjectOut(ctx, io, args[2].Pointer(), int32(ret), usermem.IOOpts{
AddressSpaceActive: true,
})
return 0, err
}
// foregroundProcessGroup sets tm's foreground process.
func (tm *Terminal) setForegroundProcessGroup(ctx context.Context, io usermem.IO, args arch.SyscallArguments, isMaster bool) (uintptr, error) {
task := kernel.TaskFromContext(ctx)
if task == nil {
panic("setForegroundProcessGroup must be called from a task context")
}
// Read in the process group ID.
var pgid int32
if _, err := usermem.CopyObjectIn(ctx, io, args[2].Pointer(), &pgid, usermem.IOOpts{
AddressSpaceActive: true,
}); err != nil {
return 0, err
}
ret, err := task.ThreadGroup().SetForegroundProcessGroup(tm.tty(isMaster), kernel.ProcessGroupID(pgid))
return uintptr(ret), err
}
func (tm *Terminal) tty(isMaster bool) *kernel.TTY {
if isMaster {
return tm.masterKTTY
}
return tm.slaveKTTY
}
// LINT.ThenChange(../../fsimpl/devpts/terminal.go)
|