/
secrets.go
60 lines (48 loc) · 1.3 KB
/
secrets.go
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package common
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"encoding/base64"
"errors"
"io"
)
func GenerateKey() ([]byte, error) {
key := make([]byte, 32)
_, err := rand.Read(key)
if err != nil {
return nil, err
}
return key, nil
}
func Encrypt(secretValue string, key []byte) (string, error) {
block, err := aes.NewCipher(key)
if err != nil {
return "", err
}
plaintext := []byte(secretValue)
ciphertext := make([]byte, aes.BlockSize+len(plaintext))
iv := ciphertext[:aes.BlockSize]
if _, err := io.ReadFull(rand.Reader, iv); err != nil {
return "", err
}
stream := cipher.NewCFBEncrypter(block, iv)
stream.XORKeyStream(ciphertext[aes.BlockSize:], plaintext)
return base64.URLEncoding.EncodeToString(ciphertext), nil
}
func Decrypt(encryptedValue string, key []byte) (string, error) {
ciphertext, _ := base64.URLEncoding.DecodeString(encryptedValue)
block, err := aes.NewCipher(key)
if err != nil {
return "", err
}
if len(ciphertext) < aes.BlockSize {
return "", errors.New("ciphertext too short")
}
iv := ciphertext[:aes.BlockSize]
ciphertext = ciphertext[aes.BlockSize:]
stream := cipher.NewCFBDecrypter(block, iv)
// XORKeyStream can work in-place if the two arguments are the same.
stream.XORKeyStream(ciphertext, ciphertext)
return string(ciphertext), nil
}