-
Notifications
You must be signed in to change notification settings - Fork 0
/
sign.go
executable file
·47 lines (37 loc) · 968 Bytes
/
sign.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
package secure
import (
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/sha256"
)
// RSASignWithPSS signs a plain text using a private key.
func RSASignWithPSS(plainText []byte, privKey *rsa.PrivateKey) ([]byte, error) {
textHash := sha256.New()
_, err := textHash.Write(plainText)
if err != nil {
return nil, err
}
textHashSum := textHash.Sum(nil)
rng := rand.Reader
signature, err := rsa.SignPSS(rng, privKey, crypto.SHA256, textHashSum, nil)
if err != nil {
return nil, err
}
s := EncodeBase64(signature)
return s, nil
}
// RSAVerifyWithPSS verifies a signed text using a public key.
func RSAVerifyWithPSS(signedText []byte, signature []byte, pubKey *rsa.PublicKey) error {
s, err := DecodeBase64(signature)
if err != nil {
return err
}
textHash := sha256.New()
_, err = textHash.Write(signedText)
if err != nil {
return err
}
textHashSum := textHash.Sum(nil)
return rsa.VerifyPSS(pubKey, crypto.SHA256, textHashSum, s, nil)
}