#------------------------------------------------------------------------------ # $File: syd,v $ # syd: file(1) magic for syd(1) encrypted files # # From: Ali Polatel # Documentation: https://man.exherbo.org/syd.7.html#Crypt_Sandboxing # No defined extension yet; files are recognized by magic header only. # # Layout: # 0..3 : "\x7fSYD" # 4 : version byte (current API: 3) # 5..36 : HMAC (32 bytes, SHA256) # 37..52 : IV (16 bytes) # 53.. : ciphertext (AES-256-CTR) #------------------------------------------------------------------------------ # Header and version 0 string \x7fSYD SYD encrypted file >4 ubyte x \b, version %u # Version 3: algorithm + HMAC/IV as hex blobs + ciphertext size >>4 ubyte =3 \b, AES-256-CTR; HMAC-SHA256: >>>5 belong x \b%08x >>>9 belong x \b%08x >>>13 belong x \b%08x >>>17 belong x \b%08x >>>21 belong x \b%08x >>>25 belong x \b%08x >>>29 belong x \b%08x >>>33 belong x \b%08x >>>37 belong x \b, IV:%08x >>>41 belong x \b%08x >>>45 belong x \b%08x >>>49 belong x \b%08x >>>-0 offset-53 x \b, ciphertext %llu bytes # End of syd