go back to using CFB for AES decryption/encryption for 2FA (#3274)

This commit is contained in:
Morgan Bazalgette 2017-12-31 03:19:42 +01:00 committed by Lauris BH
parent d2736e268b
commit edce41ae65
1 changed files with 44 additions and 3 deletions

View File

@ -5,11 +5,15 @@
package models
import (
"crypto/aes"
"crypto/cipher"
"crypto/md5"
"crypto/rand"
"crypto/subtle"
"encoding/base64"
"errors"
"io"
"github.com/Unknwon/com"
"github.com/pquerna/otp/totp"
"code.gitea.io/gitea/modules/base"
@ -52,7 +56,7 @@ func (t *TwoFactor) getEncryptionKey() []byte {
// SetSecret sets the 2FA secret.
func (t *TwoFactor) SetSecret(secret string) error {
secretBytes, err := com.AESGCMEncrypt(t.getEncryptionKey(), []byte(secret))
secretBytes, err := aesEncrypt(t.getEncryptionKey(), []byte(secret))
if err != nil {
return err
}
@ -66,7 +70,7 @@ func (t *TwoFactor) ValidateTOTP(passcode string) (bool, error) {
if err != nil {
return false, err
}
secret, err := com.AESGCMDecrypt(t.getEncryptionKey(), decodedStoredSecret)
secret, err := aesDecrypt(t.getEncryptionKey(), decodedStoredSecret)
if err != nil {
return false, err
}
@ -74,6 +78,43 @@ func (t *TwoFactor) ValidateTOTP(passcode string) (bool, error) {
return totp.Validate(passcode, secretStr), nil
}
// aesEncrypt encrypts text and given key with AES.
func aesEncrypt(key, text []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
b := base64.StdEncoding.EncodeToString(text)
ciphertext := make([]byte, aes.BlockSize+len(b))
iv := ciphertext[:aes.BlockSize]
if _, err := io.ReadFull(rand.Reader, iv); err != nil {
return nil, err
}
cfb := cipher.NewCFBEncrypter(block, iv)
cfb.XORKeyStream(ciphertext[aes.BlockSize:], []byte(b))
return ciphertext, nil
}
// aesDecrypt decrypts text and given key with AES.
func aesDecrypt(key, text []byte) ([]byte, error) {
block, err := aes.NewCipher(key)
if err != nil {
return nil, err
}
if len(text) < aes.BlockSize {
return nil, errors.New("ciphertext too short")
}
iv := text[:aes.BlockSize]
text = text[aes.BlockSize:]
cfb := cipher.NewCFBDecrypter(block, iv)
cfb.XORKeyStream(text, text)
data, err := base64.StdEncoding.DecodeString(string(text))
if err != nil {
return nil, err
}
return data, nil
}
// NewTwoFactor creates a new two-factor authentication token.
func NewTwoFactor(t *TwoFactor) error {
err := t.GenerateScratchToken()