harness-drone/store/shared/encrypt/aesgcm.go
2019-02-28 12:49:04 -08:00

59 lines
1.4 KiB
Go

// Copyright 2019 Drone IO, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package encrypt
import (
"crypto/cipher"
"crypto/rand"
"errors"
"io"
)
type aesgcm struct {
block cipher.Block
}
func (e *aesgcm) Encrypt(plaintext string) ([]byte, error) {
gcm, err := cipher.NewGCM(e.block)
if err != nil {
return nil, err
}
nonce := make([]byte, gcm.NonceSize())
_, err = io.ReadFull(rand.Reader, nonce)
if err != nil {
return nil, err
}
return gcm.Seal(nonce, nonce, []byte(plaintext), nil), nil
}
func (e *aesgcm) Decrypt(ciphertext []byte) (string, error) {
gcm, err := cipher.NewGCM(e.block)
if err != nil {
return "", err
}
if len(ciphertext) < gcm.NonceSize() {
return "", errors.New("malformed ciphertext")
}
plaintext, err := gcm.Open(nil,
ciphertext[:gcm.NonceSize()],
ciphertext[gcm.NonceSize():],
nil,
)
return string(plaintext), err
}