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
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
|
// 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 linux
import (
"fmt"
"strings"
"gvisor.googlesource.com/gvisor/pkg/abi"
"gvisor.googlesource.com/gvisor/pkg/binary"
)
// Constants for open(2).
const (
O_ACCMODE = 00000003
O_RDONLY = 00000000
O_WRONLY = 00000001
O_RDWR = 00000002
O_CREAT = 00000100
O_EXCL = 00000200
O_NOCTTY = 00000400
O_TRUNC = 00001000
O_APPEND = 00002000
O_NONBLOCK = 00004000
O_ASYNC = 00020000
O_DIRECT = 00040000
O_LARGEFILE = 00100000
O_DIRECTORY = 00200000
O_NOFOLLOW = 00400000
O_CLOEXEC = 02000000
O_SYNC = 04010000
O_PATH = 010000000
)
// Constants for fstatat(2).
const (
AT_SYMLINK_NOFOLLOW = 0x100
)
// Constants for mount(2).
const (
MS_RDONLY = 0x1
MS_NOSUID = 0x2
MS_NODEV = 0x4
MS_NOEXEC = 0x8
MS_SYNCHRONOUS = 0x10
MS_REMOUNT = 0x20
MS_MANDLOCK = 0x40
MS_DIRSYNC = 0x80
MS_NOATIME = 0x400
MS_NODIRATIME = 0x800
MS_BIND = 0x1000
MS_MOVE = 0x2000
MS_REC = 0x4000
MS_POSIXACL = 0x10000
MS_UNBINDABLE = 0x20000
MS_PRIVATE = 0x40000
MS_SLAVE = 0x80000
MS_SHARED = 0x100000
MS_RELATIME = 0x200000
MS_KERNMOUNT = 0x400000
MS_I_VERSION = 0x800000
MS_STRICTATIME = 0x1000000
MS_MGC_VAL = 0xC0ED0000
MS_MGC_MSK = 0xffff0000
)
// Constants for umount2(2).
const (
MNT_FORCE = 0x1
MNT_DETACH = 0x2
MNT_EXPIRE = 0x4
UMOUNT_NOFOLLOW = 0x8
)
// Constants for unlinkat(2).
const (
AT_REMOVEDIR = 0x200
)
// Constants for linkat(2) and fchownat(2).
const (
AT_SYMLINK_FOLLOW = 0x400
AT_EMPTY_PATH = 0x1000
)
// Constants for all file-related ...at(2) syscalls.
const (
AT_FDCWD = -100
)
// Special values for the ns field in utimensat(2).
const (
UTIME_NOW = ((1 << 30) - 1)
UTIME_OMIT = ((1 << 30) - 2)
)
// MaxSymlinkTraversals is the maximum number of links that will be followed by
// the kernel to resolve a symlink.
const MaxSymlinkTraversals = 40
// Constants for flock(2).
const (
LOCK_SH = 1 // shared lock
LOCK_EX = 2 // exclusive lock
LOCK_NB = 4 // or'd with one of the above to prevent blocking
LOCK_UN = 8 // remove lock
)
// Values for mode_t.
const (
FileTypeMask = 0170000
ModeSocket = 0140000
ModeSymlink = 0120000
ModeRegular = 0100000
ModeBlockDevice = 060000
ModeDirectory = 040000
ModeCharacterDevice = 020000
ModeNamedPipe = 010000
ModeSetUID = 04000
ModeSetGID = 02000
ModeSticky = 01000
ModeUserAll = 0700
ModeUserRead = 0400
ModeUserWrite = 0200
ModeUserExec = 0100
ModeGroupAll = 0070
ModeGroupRead = 0040
ModeGroupWrite = 0020
ModeGroupExec = 0010
ModeOtherAll = 0007
ModeOtherRead = 0004
ModeOtherWrite = 0002
ModeOtherExec = 0001
PermissionsMask = 0777
)
// Values for preadv2/pwritev2.
const (
RWF_HIPRI = 0x00000001
RWF_DSYNC = 0x00000002
RWF_SYNC = 0x00000004
RWF_VALID = RWF_HIPRI | RWF_DSYNC | RWF_SYNC
)
// Stat represents struct stat.
type Stat struct {
Dev uint64
Ino uint64
Nlink uint64
Mode uint32
UID uint32
GID uint32
X_pad0 int32
Rdev uint64
Size int64
Blksize int64
Blocks int64
ATime Timespec
MTime Timespec
CTime Timespec
X_unused [3]int64
}
// SizeOfStat is the size of a Stat struct.
var SizeOfStat = binary.Size(Stat{})
// FileMode represents a mode_t.
type FileMode uint
// Permissions returns just the permission bits.
func (m FileMode) Permissions() FileMode {
return m & PermissionsMask
}
// FileType returns just the file type bits.
func (m FileMode) FileType() FileMode {
return m & FileTypeMask
}
// ExtraBits returns everything but the file type and permission bits.
func (m FileMode) ExtraBits() FileMode {
return m &^ (PermissionsMask | FileTypeMask)
}
// String returns a string representation of m.
func (m FileMode) String() string {
var s []string
if ft := m.FileType(); ft != 0 {
s = append(s, fileType.Parse(uint64(ft)))
}
if eb := m.ExtraBits(); eb != 0 {
s = append(s, modeExtraBits.Parse(uint64(eb)))
}
s = append(s, fmt.Sprintf("0o%o", m.Permissions()))
return strings.Join(s, "|")
}
var modeExtraBits = abi.FlagSet{
{
Flag: ModeSetUID,
Name: "S_ISUID",
},
{
Flag: ModeSetGID,
Name: "S_ISGID",
},
{
Flag: ModeSticky,
Name: "S_ISVTX",
},
}
var fileType = abi.ValueSet{
ModeSocket: "S_IFSOCK",
ModeSymlink: "S_IFLINK",
ModeRegular: "S_IFREG",
ModeBlockDevice: "S_IFBLK",
ModeDirectory: "S_IFDIR",
ModeCharacterDevice: "S_IFCHR",
ModeNamedPipe: "S_IFIFO",
}
// Constants for memfd_create(2). Source: include/uapi/linux/memfd.h
const (
MFD_CLOEXEC = 0x0001
MFD_ALLOW_SEALING = 0x0002
)
// Constants related to file seals. Source: include/uapi/{asm-generic,linux}/fcntl.h
const (
F_LINUX_SPECIFIC_BASE = 1024
F_ADD_SEALS = F_LINUX_SPECIFIC_BASE + 9
F_GET_SEALS = F_LINUX_SPECIFIC_BASE + 10
F_SEAL_SEAL = 0x0001 // Prevent further seals from being set.
F_SEAL_SHRINK = 0x0002 // Prevent file from shrinking.
F_SEAL_GROW = 0x0004 // Prevent file from growing.
F_SEAL_WRITE = 0x0008 // Prevent writes.
)
|
