blocksize, size int64
	algorithm       BitrotAlgorithm
	shouldFail      bool
}{
	{dataBlocks: 2, disks: 4, offDisks: 1, badDisks: 0, badStaleDisks: 0, blocksize: int64(blockSizeV2), size: oneMiByte, algorithm: SHA256, shouldFail: false},                   // 0
	{dataBlocks: 3, disks: 6, offDisks: 2, badDisks: 0, badStaleDisks: 0, blocksize: int64(blockSizeV2), size: oneMiByte, algorithm: BLAKE2b512, shouldFail: false},               // 1

	// is not supported.
	ErrInvalidEncryptionMethod = Errorf("The encryption method is not supported")

	// ErrInvalidCustomerAlgorithm indicates that the specified SSE-C algorithm
	// is not supported.
	ErrInvalidCustomerAlgorithm = Errorf("The SSE-C algorithm is not supported")

	// ErrMissingCustomerKey indicates that the HTTP headers contains no SSE-C client key.

	}
	for algorithm := range bitrotAlgorithms {
		if !algorithm.Available() {
			continue
		}

		checksum, err := hex.DecodeString(checksums[algorithm])
		if err != nil {
			logger.Fatal(errSelfTestFailure, fmt.Sprintf("bitrot: failed to decode %v checksum %s for selftest: %v", algorithm, checksums[algorithm], err))
		}
		var (
			hash = algorithm.New()

		}
	}
	iv, err := sioutil.Random(16)
	if err != nil {
		return DEK{}, err
	}

	var algorithm string
	if sioutil.NativeAES() {
		algorithm = algorithmAESGCM
	} else {
		algorithm = algorithmChaCha20Poly1305
	}

	var aead cipher.AEAD
	switch algorithm {
	case algorithmAESGCM:
		mac := hmac.New(sha256.New, kms.key)
		mac.Write(iv)
		sealingKey := mac.Sum(nil)

var errFileCorrupt = StorageErr("file is corrupted")

// errBitrotHashAlgoInvalid - the algo for bit-rot hash
// verification is empty or invalid.
var errBitrotHashAlgoInvalid = StorageErr("bit-rot hash algorithm is invalid")

// errCrossDeviceLink - rename across devices not allowed.
var errCrossDeviceLink = StorageErr("Rename across devices not allowed, please fix your backend configuration")

				continue
			}
			if object.IsDeleteMarker {
				log.Println("SKIPPED: DELETE marker object:", objFullPath(object))
				continue
			}
			if _, ok := object.UserMetadata["X-Amz-Server-Side-Encryption-Customer-Algorithm"]; ok {
				log.Println("SKIPPED: Objects encrypted with SSE-C do not have md5sum as ETag:", objFullPath(object))
				continue
			}
			if v, ok := object.UserMetadata["X-Amz-Server-Side-Encryption"]; ok && v == "aws:kms" {

func (key *ObjectKey) Unseal(extKey []byte, sealedKey SealedKey, domain, bucket, object string) error {
	var unsealConfig sio.Config
	switch sealedKey.Algorithm {
	default:
		return Errorf("The sealing algorithm '%s' is not supported", sealedKey.Algorithm)
	case SealAlgorithm:
		mac := hmac.New(sha256.New, extKey)
		mac.Write(sealedKey.IV[:])
		mac.Write([]byte(domain))
		mac.Write([]byte(SealAlgorithm))

func (ssekms) CreateMetadata(metadata map[string]string, keyID string, kmsKey []byte, sealedKey SealedKey, ctx kms.Context) map[string]string {
	if sealedKey.Algorithm != SealAlgorithm {
		logger.CriticalIf(context.Background(), Errorf("The seal algorithm '%s' is invalid for SSE-S3", sealedKey.Algorithm))
	}

	// There are two possibilities:
	// - We use a KMS -> There must be non-empty key ID and a KMS data key.

type preSignValues struct {
	signValues
	Date    time.Time
	Expires time.Duration
}

// Parses signature version '4' query string of the following form.
//
//	querystring = X-Amz-Algorithm=algorithm
//	querystring += &X-Amz-Credential= urlencode(accessKey + '/' + credential_scope)
//	querystring += &X-Amz-Date=date
//	querystring += &X-Amz-Expires=timeout interval

### Custom Algorithms (SFTP)

Custom algorithms can be specified via command line parameters.
Algorithms are comma separated. 
Note that valid values does not in all cases represent default values.

`--sftp=pub-key-algos=...` specifies the supported client public key
authentication algorithms. Note that this doesn't include certificate types