Add support for PASERK Type: local-pw

[daviddesmet]

PASERK Type: local-pw

This PASERK is a key intended for local PASETOs, encrypted with a password.

Format

k[version].local-pw.[data]

Where [data] is the base64url-encoded payload, defined by each version.

ID Serialization

See lid.

Operations

See PBKW for the algorithm used.

PASERK Versions

Versions 1 and 3

Starting Byte	Length	Definition
0	32	PBKDF2-SHA384 Salt (salt)
32	4	Iteration count (i)
36	16	AES-CTR nonce (n)
52	32	Encrypted Data Key (edk)
84	48	Authentication tag (t)

Total decoded length: 132 bytes

The iteration count (i) MUST be encoded as a 32-bit unsigned
integer in big-endian byte order.

Versions 2 and 4

Starting Byte	Length	Definition
0	16	Argon2id Salt (salt)
16	8	Argon2id Memory Cost (mem)
24	4	Argon2id Time Cost (time)
28	4	Argon2id Parallelism (para)
32	24	XChaCha20 nonce (n)
56	32	Encrypted Data Key (edk)
88	32	Authentication tag (t)

Total decoded length: 120 bytes

The Argon2id parameters (mem, time, para) MUST be encoded as
unsigned integers in big-endian byte order. mem is 64-bit; the
other parameters are 32-bit.

Examples

k1.local-pw.TikhC_wHVYtg1T2enmE6eR2KW9KeW_GqtbSU3HQ5kxkAAAPoq1eXdbqYsbIvE7YBFYFlLLgm7RWC4Ks2jLiNDZObdusSFRP45aJ_7Jkt9tzspqRS95ZCLAID3IkSTEg2WpLk7jKJMmtg4V0EK3SkEYC5AJOnGd3VFMlWi0qXQk9ULIvv

k2.local-pw.w_h1_Ul9E041QJl8m9n7lAAAAAAEAAAAAAAAAgAAAAHslzni8NnrQ02dsjBknexAKjxpd-1BKxK-P1ZdSVJYiimOOAuaIu3jLyZSBDx1VNqzyH7MGaQe1YGqcEyT7GghPssmLA46BipTj3ji9xqRHO_7twcqCheD

k3.local-pw.L4xcw6PFvnL9pJAuhaieAT8_Ko4YlQpx70uYSAa6WakAAAPorOFKZxUYOusjRpqLe7GShAQ2z7v38wL9tUvOP2ffCVmhznjyitHhEGjd1FywEFzIHuBypneYqVSej5J2ZB-8uSahQ2MW1fK5cV1ZMz3myN0CTNk9uxXSJvccR64low9P

k4.local-pw._bru5tnkPSFXOtKhBTmW4gAAAAAEAAAAAAAAAgAAAAGKI3PyFS2vyQ9o5qowCR_GUXskLmdV1bjjc3vqnbwN7hVG1lAUCGjElTGIoH-K6lnkHnP4uaFBKWEtB3xFEGzAjzBSnl_JBmwLYK5jstjAV6LnJm_NOt0j