cs = ""
		}
		if cs != "" {
			res[typ.String()] = cs
		}
	}
	if len(res) == 0 {
		res = nil
	}
	return res
}

// ReadPartCheckSums will read all part checksums from b and return them.
func ReadPartCheckSums(b []byte) (res []map[string]string) {
	for len(b) > 0 {
		t, n := binary.Uvarint(b)
		if n <= 0 {
			break
		}
		b = b[n:]

		typ := ChecksumType(t)

		decrypted, err := o.metadataDecrypter()("object-checksum", data)
		if err != nil {
			encLogIf(GlobalContext, err)
			return
		}
		data = decrypted
	}
	cs := hash.ReadPartCheckSums(data)
	if len(cs) == len(o.Parts) {
		for i := range o.Parts {
			o.Parts[i].Checksums = cs[i]
		}
	}
	return
}

// metadataEncryptFn provides an encryption function for metadata.