Commit Graph

3 Commits

Author SHA1 Message Date
Jakob Unterwurzacher 66db3ad086 Bump on-disk version to 2 2015-11-02 23:10:11 +01:00
Jakob Unterwurzacher 902babdf22 Refactor ciphertext <-> plaintext offset translation functions
Move all the intelligence into the new file address_translation.go.
That the calculations were spread out too much became apparent when adding
the file header. This should make the code much easier to modify in the
future.
2015-11-01 12:11:36 +01:00
Jakob Unterwurzacher 76311b60f2 Add file header (on-disk-format change)
Format: [ "Version" uint16 big endian ] [ "Id" 16 random bytes ]

Quoting SECURITY.md:

* Every file has a header that contains a 16-byte random *file id*
* Each block uses the file id and its block number as GCM *authentication data*
 * This means the position of the blocks is protected as well. The blocks
   can not be reordered or copied between different files without
   causing an decryption error.
2015-11-01 01:38:27 +01:00