mirror of
https://github.com/42wim/matterbridge.git
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42 lines
1.1 KiB
Go
42 lines
1.1 KiB
Go
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// Copyright (c) 2022 Tulir Asokan
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//
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// This Source Code Form is subject to the terms of the Mozilla Public
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// License, v. 2.0. If a copy of the MPL was not distributed with this
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// file, You can obtain one at http://mozilla.org/MPL/2.0/.
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package gcmutil
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import (
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"crypto/aes"
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"crypto/cipher"
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"fmt"
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)
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func Prepare(secretKey []byte) (gcm cipher.AEAD, err error) {
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var block cipher.Block
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if block, err = aes.NewCipher(secretKey); err != nil {
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err = fmt.Errorf("failed to initialize AES cipher: %w", err)
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} else if gcm, err = cipher.NewGCM(block); err != nil {
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err = fmt.Errorf("failed to initialize GCM: %w", err)
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}
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return
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}
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func Decrypt(secretKey, iv, ciphertext, additionalData []byte) ([]byte, error) {
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if gcm, err := Prepare(secretKey); err != nil {
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return nil, err
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} else if plaintext, decryptErr := gcm.Open(nil, iv, ciphertext, additionalData); decryptErr != nil {
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return nil, decryptErr
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} else {
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return plaintext, nil
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}
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}
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func Encrypt(secretKey, iv, plaintext, additionalData []byte) ([]byte, error) {
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if gcm, err := Prepare(secretKey); err != nil {
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return nil, err
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} else {
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return gcm.Seal(nil, iv, plaintext, additionalData), nil
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}
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}
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