4. The Mandatory Audio Component (MAC)

Dieser Abschnitt bewahrt den RFC-Text zu BUSA-TLS, einschliesslich TLS 1.3 HKDF key schedule changes, Mandatory Audio Component, MAC derivation, alert handling, implementation notes, security considerations und IANA considerations.

Originaler RFC-Text

4.  The Mandatory Audio Component (MAC)

   The Mandatory Audio Component is defined as:

     MAC = SHA-256(raw_pcm(BUSA_canonical))

   where raw_pcm() denotes extraction of uncompressed PCM audio data and
   BUSA_canonical denotes the canonical form as defined in Section 2.

   The expected SHA-256 digest of the Mandatory Audio Component cannot
   be published in this document, as doing so would require reproducing
   a cryptographic commitment to a specific pressing of a commercially
   available recording.  Implementations are therefore REQUIRED to
   obtain the Mandatory Audio Component through lawful means, such as
   purchase of the original album, and derive MAC independently.

   The authors note that this is exactly as much verification as you get
   with any other out-of-band PSK, and implementations should treat it
   accordingly.  MAC is a 32-byte value.  For the avoidance of doubt, it
   is not a Message Authentication Code in this context.  The name is a
   coincidence that the authors find pleasing and intend to keep.