Function NewCryptoFromHexKey

internal/frame/crypto.go:35–52

NewCryptoFromHexKey parses a 64-char hex string into a 32-byte AES-256 key and constructs a Crypto. The same key must be configured on both client and VPS server.

(hexKey string)

// NewCryptoFromHexKey parses a 64-char hex string into a 32-byte AES-256 key
// and constructs a Crypto. The same key must be configured on both client and VPS server.
func NewCryptoFromHexKey(hexKey string) (*Crypto, error) {
	key, err := hex.DecodeString(hexKey)
	if err != nil {
		return nil, fmt.Errorf("crypto: invalid hex key: %w", err)
	}
	if len(key) != 32 {
		return nil, fmt.Errorf("crypto: key must be 32 bytes (AES-256), got %d", len(key))
	}
	block, err := aes.NewCipher(key)
	if err != nil {
		return nil, fmt.Errorf("crypto: aes new cipher: %w", err)
	}
	gcm, err := cipher.NewGCM(block)
	if err != nil {
		return nil, fmt.Errorf("crypto: new gcm: %w", err)
	}
	return &Crypto{aead: gcm}, nil
}

// Seal encrypts plaintext and returns nonce||ciphertext (tag appended by GCM).
func (c *Crypto) Seal(plaintext []byte) ([]byte, error) {