// initialization vector (IV) and the bucket/object path.
//
//  1. Encrypt:
//     Input: ClientKey, bucket, object, metadata, object_data
//     -              IV := Random({0,1}²⁵⁶)
//     -       ObjectKey := SHA256(ClientKey || Random({0,1}²⁵⁶))
//     -       KeyEncKey := HMAC-SHA256(ClientKey, IV || 'SSE-C' || 'DAREv2-HMAC-SHA256' || bucket || '/' || object)

	for i, test := range generateIVTests {
		i, test := i, test
		func() {
			defer recoverTest(i, test.ShouldPass, t)
			iv := GenerateIV(test.Random)
			if iv == [32]byte{} {
				t.Errorf("Test %d: generated IV is zero IV", i) // check that we generate random and unique IV
			}
		}()
	}
}

var sealUnsealKeyTests = []struct {
	SealExtKey, SealIV                 [32]byte

			"X-Minio-Internal-Server-Side-Encryption-Seal-Algorithm": "DAREv2-HMAC-SHA256",
			"X-Minio-Internal-Server-Side-Encryption-Iv":             "coVfGS3I/CTrqexX5vUN+PQPoP9aUFiPYYrSzqTWfBA=",
		},
		ExpectedErr: nil,
	},
	{ // 1 - Valid HTTP headers but invalid metadata entries for bucket/object2
		Headers: http.Header{

}

// GenerateIV generates a new random 256 bit IV from the provided source
// of randomness. If random is nil the default PRNG of the system
// (crypto/rand) is used.
func GenerateIV(random io.Reader) (iv [32]byte) {
	if random == nil {
		random = rand.Reader
	}
	if _, err := io.ReadFull(random, iv[:]); err != nil {
		logger.CriticalIf(context.Background(), errOutOfEntropy)
	}
	return iv
}

		ID        string `json:"id"`
		IV        []byte `json:"iv"`
		Nonce     []byte `json:"nonce"`
		Bytes     []byte `json:"bytes"`
	}
	var value JSON
	if err := json.Unmarshal(text, &value); err != nil {
		return ErrDecrypt
	}

	if value.Algorithm != AES256GCM && value.Algorithm != CHACHA20POLY1305 {
		return ErrDecrypt
	}
	if len(value.IV) != IVSize {
		return ErrDecrypt
	}

	if !ok {
		return sealedKey, Errorf("The object metadata is missing the internal sealed key for SSE-C")
	}

	// Check whether all extracted values are well-formed
	iv, err := base64.StdEncoding.DecodeString(b64IV)
	if err != nil || len(iv) != 32 {
		return sealedKey, errInvalidInternalIV
	}
	if algorithm != SealAlgorithm && algorithm != InsecureSealAlgorithm {
		return sealedKey, errInvalidInternalSealAlgorithm
	}

		return keyID, kmsKey, sealedKey, Errorf("The object metadata is missing the internal sealed KMS data key for SSE-S3")
	}

	// Check whether all extracted values are well-formed
	iv, err := base64.StdEncoding.DecodeString(b64IV)
	if err != nil || len(iv) != 32 {
		return keyID, kmsKey, sealedKey, errInvalidInternalIV
	}
	if algorithm != SealAlgorithm {
		return keyID, kmsKey, sealedKey, errInvalidInternalSealAlgorithm
	}

		return keyID, kmsKey, sealedKey, ctx, Errorf("The object metadata is missing the internal sealed KMS data key for SSE-S3")
	}

	// Check whether all extracted values are well-formed
	iv, err := base64.StdEncoding.DecodeString(b64IV)
	if err != nil || len(iv) != 32 {
		return keyID, kmsKey, sealedKey, ctx, errInvalidInternalIV
	}
	if algorithm != SealAlgorithm {
		return keyID, kmsKey, sealedKey, ctx, errInvalidInternalSealAlgorithm
	}

		Ciphertext: `{"aead":"ChaCha20Poly1305","iv":"JbI+vwvYww1lCb5VpkAFuQ==","nonce":"ARjIjJxBSD541Gz8","bytes":"KCbEc2sA0TLvA7aWTWa23AdccVfJMpOxwgG8hm+4PaNrxYfy1xFWZg2gEenVrOgv"}`,
	},
	{
		KeyID:      "my-key",
		Plaintext:  "UnPWsZgVI+T4L9WGNzFlP1PsP1Z6hn2Fx8ISeZfDGnA=",

)

var (
	errMissingInternalIV            = Errorf("The object metadata is missing the internal encryption IV")
	errMissingInternalSealAlgorithm = Errorf("The object metadata is missing the internal seal algorithm")

	errInvalidInternalIV            = Errorf("The internal encryption IV is malformed")
	errInvalidInternalSealAlgorithm = Errorf("The internal seal algorithm is invalid and not supported")
)