1. In a distributed file system that stores encrypted files across multiple computers, a method comprising: modifying one or more of the encrypted files; computing a hash value of each modified encrypted file, one or more of the modified encrypted files comprising file data and a metadata stream that comprises a header and an indexing structure, the indexing structure comprising one or more hashes of the file and a structure to access the one or more hashes of the file; collecting the hash values into a group; computing a hash value of the group; and digitally signing the hash value of the group of hash values.