Method Decrypt

flow/shared/crypto.go:60–92

Decrypt decrypts the given ciphertext using the PeerDBEncKey.

(ciphertext []byte)

// Decrypt decrypts the given ciphertext using the PeerDBEncKey.
func (key PeerDBEncKey) Decrypt(ciphertext []byte) ([]byte, error) {
	if key.ID == "" {
		return ciphertext, nil
	}

	decodedKey, err := base64.StdEncoding.DecodeString(key.Value)
	if err != nil {
		return nil, fmt.Errorf("failed to decode base64 key: %w", err)
	}

	if len(decodedKey) != 32 {
		return nil, fmt.Errorf("invalid key length, must be 32 bytes")
	}

	if len(ciphertext) < nonceSize {
		return nil, fmt.Errorf("ciphertext too short")
	}

	nonce := ciphertext[:nonceSize]
	ciphertext = ciphertext[nonceSize:]

	aead, err := chacha20poly1305.NewX(decodedKey)
	if err != nil {
		return nil, fmt.Errorf("failed to create ChaCha20-Poly1305: %w", err)
	}

	plaintext, err := aead.Open(nil, nonce, ciphertext, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to decrypt: %w", err)
	}

	return plaintext, nil
}

// Encrypt encrypts the given plaintext using the PeerDBEncKey.
func (key PeerDBEncKey) Encrypt(plaintext []byte) ([]byte, error) {