/
stringpasswordencrypt.go
91 lines (81 loc) · 2.06 KB
/
stringpasswordencrypt.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
package stringpasswordencrypt
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"encoding/base64"
"golang.org/x/crypto/scrypt"
)
// Encrypt encrypts given byte data using a given password
func Encrypt(password, value string) (string, error) {
key := []byte(password)
data := []byte(value)
key, salt, err := deriveKey(key, nil)
if err != nil {
return "", err
}
blockCipher, err := aes.NewCipher(key)
if err != nil {
return "", err
}
gcm, err := cipher.NewGCM(blockCipher)
if err != nil {
return "", err
}
nonce := make([]byte, gcm.NonceSize())
if _, err = rand.Read(nonce); err != nil {
return "", err
}
ciphertext := gcm.Seal(nonce, nonce, data, nil)
ciphertext = append(ciphertext, salt...)
return string(ciphertext), nil
}
// Decrypt decrypts given byte ciphertext using a given password
func Decrypt(password, value string) (string, error) {
key := []byte(password)
data := []byte(value)
salt, data := data[len(data)-32:], data[:len(data)-32]
key, _, err := deriveKey(key, salt)
if err != nil {
return "", err
}
blockCipher, err := aes.NewCipher(key)
if err != nil {
return "", err
}
gcm, err := cipher.NewGCM(blockCipher)
if err != nil {
return "", err
}
nonce, ciphertext := data[:gcm.NonceSize()], data[gcm.NonceSize():]
plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
if err != nil {
return "", err
}
return string(plaintext), nil
}
func Base64Encode(data string) string {
return base64.URLEncoding.EncodeToString([]byte(data))
}
func Base64Decode(data string) (string, error) {
encrypted, err := base64.URLEncoding.DecodeString(data)
if err != nil {
return "", err
}
return string(encrypted), nil
}
func deriveKey(password, salt []byte) ([]byte, []byte, error) {
if salt == nil {
salt = make([]byte, 32)
if _, err := rand.Read(salt); err != nil {
return nil, nil, err
}
}
// https://blog.filippo.io/the-scrypt-parameters/
// interactive logins: 2^15 — 1 << 15 — 32 768 — 86ms
key, err := scrypt.Key(password, salt, 32768, 8, 1, 32)
if err != nil {
return nil, nil, err
}
return key, salt, nil
}