Writes agile encryption with Word's own parameters (AES-256-CBC in 4096-byte
segments, 100000 SHA-512 rounds, HMAC integrity) into a compound file built
here — cfb.ts, MiniFAT and DIFAT included. Reads that and the older standard
encryption LibreOffice writes, whose package is AES-ECB. Verified both ways
against LibreOffice.
Writes LibreOffice's whole-package form: AES-256-GCM keyed by Argon2id over
SHA-256 of the password, the deflated package as one encrypted-package entry.
Reads that plus the per-entry AES-CBC/GCM form with PBKDF2 that every earlier
version writes; the nonce sits ahead of the ciphertext, which no manifest says.
Blowfish and unknown algorithms report an unsupported-encryption error.
Steffen Becker