APPARATUS AND METHOD FOR CRYPTOGRAPHIC PROTECTION OF DIRECTORIES AND FILES
A computer readable storage medium includes executable instructions to encrypt a file with a file encryption key to produce an encrypted file. The file encryption key is encrypted with a directory encryption key to produce an encrypted file encryption key. The directory encryption key is encrypted with a public key of a user within a group to produce an encrypted directory encryption key.
1 . A computer readable storage medium, comprising executable instructions to:
encrypt a file with a file encryption key to produce an encrypted file;
encrypt the file encryption key with a directory encryption key to produce an encrypted file encryption key; and
encrypt the directory encryption key with a public key of a user within a group to produce an encrypted directory encryption key.
2 . The computer readable storage medium of claim 1 further comprising executable instructions to:
decrypt the encrypted directory encryption key with a private key of the user within the group to produce the directory encryption key.
3 . The computer readable storage medium of claim 2 further comprising executable instructions to:
decrypt the encrypted file encryption key with the directory encryption key to produce the file encryption key.
4 . The computer readable storage medium of claim 3 further comprising executable instructions to:
decrypt the encrypted file with the file encryption key to produce the file.
5 . The computer readable storage medium of claim 1 wherein the file encryption key is a symmetric key.
6 . The computer readable storage medium of claim 1 wherein the directory encryption key is a symmetric key.
7 . The computer readable storage medium of claim 1 further comprising executable instructions to securely distribute the directory encryption key to a user within the group of users.
8 . The computer readable storage medium of claim 7 further comprising executable instructions to encrypt the directory encryption key with a key common to each user within the group.
9 . The computer readable storage medium of claim 1 further comprising executable instructions to encrypt file information with the directory encryption key.
10 . A computer readable storage medium, comprising executable instructions to:
generate a directory encryption key;
generate file encryption keys for each file in a directory;
select a file encryption key for each file in the directory;
encrypt each file in the directory with a file encryption key;
encrypt each file encryption key with the directory encryption key; and
encrypt the directory encryption key with a public key.
11 . The computer readable storage medium of claim 10 further comprising executable instructions to use a private key to decrypt the directory encryption key.
12 . The computer readable storage medium of claim 11 further comprising executable instructions to use the directory encryption key to decrypt a file encryption key.
13 . The computer readable storage medium of claim 12 further comprising executable instructions to decrypt a file with the file encryption key.
14 . The computer readable storage medium of claim 10 further comprising executable instructions to securely distribute the directory encryption key to a user within a group.
15 . The computer readable storage medium of claim 14 further comprising executable instructions to encrypt the directory encryption key with a key common to each user within the group.
16 . The computer readable storage medium of claim 15 further comprising executable instructions to encrypt file information with the directory encryption key.
17 . The computer readable storage medium of claim 10 wherein the file encryption key is a symmetric key.
18 . The computer readable storage medium of claim 10 wherein the directory encryption key is a symmetric key.