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
|
package fusefrontend
import (
"context"
"os"
"path/filepath"
"syscall"
"golang.org/x/sys/unix"
"github.com/hanwen/go-fuse/v2/fs"
"github.com/hanwen/go-fuse/v2/fuse"
"github.com/rfjakob/gocryptfs/internal/nametransform"
"github.com/rfjakob/gocryptfs/internal/syscallcompat"
"github.com/rfjakob/gocryptfs/internal/tlog"
)
// Node is a file or directory in the filesystem tree
// in a gocryptfs mount.
type Node struct {
fs.Inode
}
// path returns the relative plaintext path of this node
func (n *Node) path() string {
return n.Path(n.Root())
}
func (n *Node) rootNode() *RootNode {
return n.Root().Operations().(*RootNode)
}
// Lookup - FUSE call for discovering a file.
func (n *Node) Lookup(ctx context.Context, name string, out *fuse.EntryOut) (*fs.Inode, syscall.Errno) {
rn := n.rootNode()
p := filepath.Join(n.path(), name)
if rn.isFiltered(p) {
return nil, syscall.EPERM
}
dirfd, cName, err := rn.openBackingDir(p)
if err != nil {
return nil, fs.ToErrno(err)
}
defer syscall.Close(dirfd)
// Get device number and inode number into `st`
st, err := syscallcompat.Fstatat2(dirfd, cName, unix.AT_SYMLINK_NOFOLLOW)
if err != nil {
return nil, fs.ToErrno(err)
}
// Get unique inode number
rn.inoMap.TranslateStat(st)
out.Attr.FromStat(st)
// Create child node
id := fs.StableAttr{
Mode: uint32(st.Mode),
Gen: 1,
Ino: st.Ino,
}
node := &Node{}
ch := n.NewInode(ctx, node, id)
return ch, 0
}
// GetAttr - FUSE call for stat()ing a file.
//
// GetAttr is symlink-safe through use of openBackingDir() and Fstatat().
func (n *Node) Getattr(ctx context.Context, f fs.FileHandle, out *fuse.AttrOut) syscall.Errno {
rn := n.rootNode()
dirfd, cName, err := rn.openBackingDir(n.path())
if err != nil {
return fs.ToErrno(err)
}
defer syscall.Close(dirfd)
st, err := syscallcompat.Fstatat2(dirfd, cName, unix.AT_SYMLINK_NOFOLLOW)
if err != nil {
return fs.ToErrno(err)
}
rn.inoMap.TranslateStat(st)
out.Attr.FromStat(st)
return 0
}
// Create - FUSE call. Creates a new file.
//
// Symlink-safe through the use of Openat().
func (n *Node) Create(ctx context.Context, name string, flags uint32, mode uint32, out *fuse.EntryOut) (inode *fs.Inode, fh fs.FileHandle, fuseFlags uint32, errno syscall.Errno) {
rn := n.rootNode()
path := filepath.Join(n.path(), name)
if rn.isFiltered(path) {
return nil, nil, 0, syscall.EPERM
}
dirfd, cName, err := rn.openBackingDir(path)
if err != nil {
return nil, nil, 0, fs.ToErrno(err)
}
defer syscall.Close(dirfd)
fd := -1
// Make sure context is nil if we don't want to preserve the owner
if !rn.args.PreserveOwner {
ctx = nil
}
newFlags := rn.mangleOpenFlags(flags)
// Handle long file name
if !rn.args.PlaintextNames && nametransform.IsLongContent(cName) {
// Create ".name"
err = rn.nameTransform.WriteLongNameAt(dirfd, cName, path)
if err != nil {
return nil, nil, 0, fs.ToErrno(err)
}
// Create content
fd, err = syscallcompat.OpenatUserCtx(dirfd, cName, newFlags|syscall.O_CREAT|syscall.O_EXCL, mode, ctx)
if err != nil {
nametransform.DeleteLongNameAt(dirfd, cName)
}
} else {
// Create content, normal (short) file name
fd, err = syscallcompat.OpenatUserCtx(dirfd, cName, newFlags|syscall.O_CREAT|syscall.O_EXCL, mode, ctx)
}
if err != nil {
// xfstests generic/488 triggers this
if err == syscall.EMFILE {
var lim syscall.Rlimit
syscall.Getrlimit(syscall.RLIMIT_NOFILE, &lim)
tlog.Warn.Printf("Create %q: too many open files. Current \"ulimit -n\": %d", cName, lim.Cur)
}
return nil, nil, 0, fs.ToErrno(err)
}
// Get device number and inode number into `st`
st, err := syscallcompat.Fstatat2(dirfd, cName, unix.AT_SYMLINK_NOFOLLOW)
if err != nil {
return nil, nil, 0, fs.ToErrno(err)
}
// Get unique inode number
rn.inoMap.TranslateStat(st)
out.Attr.FromStat(st)
// Create child node
id := fs.StableAttr{
Mode: uint32(st.Mode),
Gen: 1,
Ino: st.Ino,
}
node := &Node{}
ch := n.NewInode(ctx, node, id)
f := os.NewFile(uintptr(fd), cName)
return ch, NewFile2(f, rn, st), 0, 0
}
// Unlink - FUSE call. Delete a file.
//
// Symlink-safe through use of Unlinkat().
func (n *Node) Unlink(ctx context.Context, name string) syscall.Errno {
rn := n.rootNode()
p := filepath.Join(n.path(), name)
if rn.isFiltered(p) {
return syscall.EPERM
}
dirfd, cName, err := rn.openBackingDir(p)
if err != nil {
return fs.ToErrno(err)
}
defer syscall.Close(dirfd)
// Delete content
err = syscallcompat.Unlinkat(dirfd, cName, 0)
if err != nil {
return fs.ToErrno(err)
}
// Delete ".name" file
if !rn.args.PlaintextNames && nametransform.IsLongContent(cName) {
err = nametransform.DeleteLongNameAt(dirfd, cName)
if err != nil {
tlog.Warn.Printf("Unlink: could not delete .name file: %v", err)
}
}
return fs.ToErrno(err)
}
|
