MinIO supports two different types of server-side encryption ([SSE](#sse)):

- **SSE-C**: The MinIO server en/decrypts an object with a secret key provided by the S3 client as part of the HTTP request headers. Therefore, [SSE-C](#ssec) requires TLS/HTTPS.
- **SSE-S3**: The MinIO server en/decrypts an object with a secret key managed by a KMS. Therefore, MinIO requires a valid KMS configuration for [SSE-S3](#sses3).

### Server-Side Encryption - Preliminaries

# sleep for replication to complete
sleep 30

# Create bucket in source cluster
echo "Create bucket in source MinIO instance"
./mc mb minio1/test-bucket --insecure

# Enable SSE KMS for the bucket
./mc encrypt set sse-kms minio-default-key minio1/test-bucket --insecure

# Load objects to source site
echo "Loading objects to source MinIO instance"
./mc cp /tmp/data/encrypted minio1/test-bucket --insecure

	AmzMetaUnencryptedContentLength = "X-Amz-Meta-X-Amz-Unencrypted-Content-Length"
	AmzMetaUnencryptedContentMD5    = "X-Amz-Meta-X-Amz-Unencrypted-Content-Md5"

	// AWS server-side encryption headers for SSE-S3, SSE-KMS and SSE-C.
	AmzServerSideEncryption                      = "X-Amz-Server-Side-Encryption"
	AmzServerSideEncryptionKmsID                 = AmzServerSideEncryption + "-Aws-Kms-Key-Id"

		return
	}

	var forceMD5 []byte
	// Optimization: If SSE-KMS and SSE-C did not request Content-Md5. Use uuid as etag. Optionally enable this also
	// for server that is started with `--no-compat`.
	kind, _ := crypto.IsRequested(formValues)
	if !etag.ContentMD5Requested(formValues) && (kind == crypto.SSEC || kind == crypto.S3KMS || !globalServerCtxt.StrictS3Compat) {
		forceMD5 = mustGetUUIDBytes()
	}

			z.UserTags, bts, err = msgp.ReadStringBytes(bts)
			if err != nil {
				err = msgp.WrapError(err, "UserTags")
				return
			}
		case "SSEC":
			z.SSEC, bts, err = msgp.ReadBoolBytes(bts)
			if err != nil {
				err = msgp.WrapError(err, "SSEC")
				return
			}
		case "ReplicationStatus":
			bts, err = z.ReplicationStatus.UnmarshalMsg(bts)
			if err != nil {

	VersionID                  string
	ETag                       string
	Size                       int64
	ActualSize                 int64
	ModTime                    time.Time
	UserTags                   string
	SSEC                       bool
	ReplicationStatus          replication.StatusType
	ReplicationStatusInternal  string
	VersionPurgeStatusInternal string
	VersionPurgeStatus         VersionPurgeStatusType

				writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrInvalidBucketName), r.URL)
				return
			}
		}
		// Deny SSE-C requests if not made over TLS
		if !globalIsTLS && (crypto.SSEC.IsRequested(r.Header) || crypto.SSECopy.IsRequested(r.Header)) {
			if r.Method == http.MethodHead {
				if ok {
					tc.FuncName = "handler.ValidRequest"

	// Therefore, we adjust all ETags sent by the client to match what is stored
	// on the backend.
	kind, _ := crypto.IsEncrypted(fi.Metadata)

	var objectEncryptionKey []byte
	switch kind {
	case crypto.SSEC:
		if checksumType.IsSet() {
			if opts.EncryptFn == nil {
				return oi, crypto.ErrMissingCustomerKey
			}
			baseKey := opts.EncryptFn("", nil)
			if len(baseKey) != 32 {

		return &GetObjectReader{
			ObjInfo: objInfo,
		}, toObjectErr(errMethodNotAllowed, bucket, object)
	}

	// Set NoDecryption for SSE-C objects and if replication request
	if crypto.SSEC.IsEncrypted(objInfo.UserDefined) && opts.ReplicationRequest {
		opts.NoDecryption = true
	}

	if objInfo.Size == 0 {
		if _, _, err := rs.GetOffsetLength(objInfo.Size); err != nil {

type ssekms struct{}

var (
	// S3KMS represents AWS SSE-KMS. It provides functionality to
	// handle SSE-KMS requests.
	S3KMS = ssekms{}

	_ Type = S3KMS
)

// String returns the SSE domain as string. For SSE-KMS the
// domain is "SSE-KMS".
func (ssekms) String() string { return "SSE-KMS" }

// IsRequested returns true if the HTTP headers contains
// at least one SSE-KMS header.
func (ssekms) IsRequested(h http.Header) bool {