Alain Spineux authored Oct 06, 2022 and Eric Bollengier committed Sep 14, 2023

- this is a 64bits XXHASH64 check that replace the 32bits
- The old crc32 location is used for a "block option" bit field
- use the block header option bit field to store information about
  - if block checksum (XXH64) is used
  - encryption is used
  - if "this" block is encrypted (volume label are not)
- add encryption_command
- use the BlockNum for the IV
- new SD->Device->BlockEncryption directive to enable encryption
- the xxhas64 is in one block at the end of the header
- add documentation
- add a unittest for block_crypto, to show how to use it and do some basic
  encrypte/decrypte
- 2 options bit in the block header
    - BLKHOPT_ENCRYPT_VOL if the volume is encrypter
    - BLKHOPT_ENCRYPT_BLOCK if THIS block is encrypted
- bsdjson can display the encryption type
- high level protocol between the sd_encryption_script and the SD
  - use ENV to send the data
  - use stdout/stdin to read the answere from the keymanager
  - handle error reported by the script
- obfuscate data in the volume when needed (BlockEncryption = STRONG)
- support data spooling (don't encode data in the spool)
- support %V in edit_device_codes() but not used anymore, use environment
  instead
- add support for a master key (store encoded version of the encryption key
  and the key id of the masterkey)
- DEVICE::load_encryption_key() that call the keymanager
- Add new fields to volume label : EncCipherKey[Size] & MasterKeyId[Size]
- add int DEV_RECORD::BlockVer to know the volume version, in case we decode
  the volume header and its extra fields
- add the NULL cipher only for testing purpose
- the XXHASH is always there in the block header event when not used (set to 0)
- the block header has a constant length

# Conflicts:
#	bacula/src/stored/stored_conf.h