-
-
Notifications
You must be signed in to change notification settings - Fork 15
/
keywordfunc.go
174 lines (165 loc) · 7.7 KB
/
keywordfunc.go
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
package mtree
import (
"archive/tar"
"crypto/md5"
"crypto/sha1"
"crypto/sha256"
"crypto/sha512"
"fmt"
"hash"
"io"
"os"
"github.com/vbatts/go-mtree/pkg/govis"
//nolint:staticcheck // SA1019 yes ripemd160 is deprecated, but this is for mtree compatibility
"golang.org/x/crypto/ripemd160"
)
// KeywordFunc is the type of a function called on each file to be included in
// a DirectoryHierarchy, that will produce the string output of the keyword to
// be included for the file entry. Otherwise, empty string.
// io.Reader `r` is to the file stream for the file payload. While this
// function takes an io.Reader, the caller needs to reset it to the beginning
// for each new KeywordFunc
type KeywordFunc func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error)
var (
// KeywordFuncs is the map of all keywords (and the functions to produce them)
KeywordFuncs = map[Keyword]KeywordFunc{
"size": sizeKeywordFunc, // The size, in bytes, of the file
"type": typeKeywordFunc, // The type of the file
"time": timeKeywordFunc, // The last modification time of the file
"link": linkKeywordFunc, // The target of the symbolic link when type=link
"uid": uidKeywordFunc, // The file owner as a numeric value
"gid": gidKeywordFunc, // The file group as a numeric value
"nlink": nlinkKeywordFunc, // The number of hard links the file is expected to have
"uname": unameKeywordFunc, // The file owner as a symbolic name
"gname": gnameKeywordFunc, // The file group as a symbolic name
"mode": modeKeywordFunc, // The current file's permissions as a numeric (octal) or symbolic value
"cksum": cksumKeywordFunc, // The checksum of the file using the default algorithm specified by the cksum(1) utility
"md5": hasherKeywordFunc("md5digest", md5.New), // The MD5 message digest of the file
"md5digest": hasherKeywordFunc("md5digest", md5.New), // A synonym for `md5`
"rmd160": hasherKeywordFunc("ripemd160digest", ripemd160.New), // The RIPEMD160 message digest of the file
"rmd160digest": hasherKeywordFunc("ripemd160digest", ripemd160.New), // A synonym for `rmd160`
"ripemd160digest": hasherKeywordFunc("ripemd160digest", ripemd160.New), // A synonym for `rmd160`
"sha1": hasherKeywordFunc("sha1digest", sha1.New), // The SHA1 message digest of the file
"sha1digest": hasherKeywordFunc("sha1digest", sha1.New), // A synonym for `sha1`
"sha256": hasherKeywordFunc("sha256digest", sha256.New), // The SHA256 message digest of the file
"sha256digest": hasherKeywordFunc("sha256digest", sha256.New), // A synonym for `sha256`
"sha384": hasherKeywordFunc("sha384digest", sha512.New384), // The SHA384 message digest of the file
"sha384digest": hasherKeywordFunc("sha384digest", sha512.New384), // A synonym for `sha384`
"sha512": hasherKeywordFunc("sha512digest", sha512.New), // The SHA512 message digest of the file
"sha512digest": hasherKeywordFunc("sha512digest", sha512.New), // A synonym for `sha512`
"sha512256": hasherKeywordFunc("sha512digest", sha512.New512_256), // The SHA512/256 message digest of the file
"sha512256digest": hasherKeywordFunc("sha512digest", sha512.New512_256), // A synonym for `sha512256`
"flags": flagsKeywordFunc, // NOTE: this is a noop, but here to support the presence of the "flags" keyword.
// This is not an upstreamed keyword, but used to vary from "time", as tar
// archives do not store nanosecond precision. So comparing on "time" will
// be only seconds level accurate.
"tar_time": tartimeKeywordFunc, // The last modification time of the file, from a tar archive mtime
// This is not an upstreamed keyword, but a needed attribute for file validation.
// The pattern for this keyword key is prefixed by "xattr." followed by the extended attribute "namespace.key".
// The keyword value is the SHA1 digest of the extended attribute's value.
// In this way, the order of the keys does not matter, and the contents of the value is not revealed.
"xattr": xattrKeywordFunc,
"xattrs": xattrKeywordFunc,
}
)
var (
modeKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
permissions := info.Mode().Perm()
if os.ModeSetuid&info.Mode() > 0 {
permissions |= (1 << 11)
}
if os.ModeSetgid&info.Mode() > 0 {
permissions |= (1 << 10)
}
if os.ModeSticky&info.Mode() > 0 {
permissions |= (1 << 9)
}
return []KeyVal{KeyVal(fmt.Sprintf("mode=%#o", permissions))}, nil
}
sizeKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
if sys, ok := info.Sys().(*tar.Header); ok {
if sys.Typeflag == tar.TypeSymlink {
return []KeyVal{KeyVal(fmt.Sprintf("size=%d", len(sys.Linkname)))}, nil
}
}
return []KeyVal{KeyVal(fmt.Sprintf("size=%d", info.Size()))}, nil
}
cksumKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
if !info.Mode().IsRegular() {
return nil, nil
}
sum, _, err := cksum(r)
if err != nil {
return nil, err
}
return []KeyVal{KeyVal(fmt.Sprintf("cksum=%d", sum))}, nil
}
hasherKeywordFunc = func(name string, newHash func() hash.Hash) KeywordFunc {
return func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
if !info.Mode().IsRegular() {
return nil, nil
}
h := newHash()
if _, err := io.Copy(h, r); err != nil {
return nil, err
}
return []KeyVal{KeyVal(fmt.Sprintf("%s=%x", KeywordSynonym(name), h.Sum(nil)))}, nil
}
}
tartimeKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
return []KeyVal{KeyVal(fmt.Sprintf("tar_time=%d.%9.9d", info.ModTime().Unix(), 0))}, nil
}
timeKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
tSec := info.ModTime().Unix()
tNano := info.ModTime().Nanosecond()
return []KeyVal{KeyVal(fmt.Sprintf("time=%d.%9.9d", tSec, tNano))}, nil
}
linkKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
if sys, ok := info.Sys().(*tar.Header); ok {
if sys.Linkname != "" {
linkname, err := govis.Vis(sys.Linkname, DefaultVisFlags)
if err != nil {
return nil, nil
}
return []KeyVal{KeyVal(fmt.Sprintf("link=%s", linkname))}, nil
}
return nil, nil
}
if info.Mode()&os.ModeSymlink != 0 {
str, err := os.Readlink(path)
if err != nil {
return nil, nil
}
linkname, err := govis.Vis(str, DefaultVisFlags)
if err != nil {
return nil, nil
}
return []KeyVal{KeyVal(fmt.Sprintf("link=%s", linkname))}, nil
}
return nil, nil
}
typeKeywordFunc = func(path string, info os.FileInfo, r io.Reader) ([]KeyVal, error) {
if info.Mode().IsDir() {
return []KeyVal{"type=dir"}, nil
}
if info.Mode().IsRegular() {
return []KeyVal{"type=file"}, nil
}
if info.Mode()&os.ModeSocket != 0 {
return []KeyVal{"type=socket"}, nil
}
if info.Mode()&os.ModeSymlink != 0 {
return []KeyVal{"type=link"}, nil
}
if info.Mode()&os.ModeNamedPipe != 0 {
return []KeyVal{"type=fifo"}, nil
}
if info.Mode()&os.ModeDevice != 0 {
if info.Mode()&os.ModeCharDevice != 0 {
return []KeyVal{"type=char"}, nil
}
return []KeyVal{"type=block"}, nil
}
return nil, nil
}
)