Function timelock 

pub fn timelock(
    cadence: Option<TimeLockCadence>,
    time: Option<TimeLockTime>,
    precision: Option<TimePrecision>,
    format: Option<TimeFormat>,
    salts: Option<TimeLockSalts>,
    kdf: Option<KdfParams>,
    params: Option<TimeLockParams>,
) -> Result<TimeLockKey, TimeLockError>

Derive a 32-byte time-locked key — unified sync entry point.

Encryption path (params = None)

Set params to None and supply all of cadence, time, precision, format, salts, and kdf as Some(...). Requires the enc-timelock-keygen-input feature. After calling, use pack with the same arguments to produce a TimeLockParams header for the ciphertext.

Decryption path (params = Some(p))

Set params to Some(header) where header is the TimeLockParams read from the ciphertext. All other arguments are ignored and may be None. Requires the enc-timelock-keygen-now feature.

Errors

• TimeLockError::ForbiddenAction if the required feature is not active, or if the _at path is taken but any required Option argument is None.
• TimeLockError::Argon2 / TimeLockError::Scrypt on KDF failure.
• TimeLockError::ClockUnavailable if the OS clock is unusable (_now path).

Example

let salts = TimeLockSalts::generate();
let kdf   = KdfPreset::BalancedMac.params();

// Encryption side — lock to every Tuesday at 18:00
let enc_key = timelock(
    Some(TimeLockCadence::DayOfWeek(Weekday::Tuesday)),
    Some(TimeLockTime::new(18, 0).unwrap()),
    Some(TimePrecision::Hour),
    Some(TimeFormat::Hour24),
    Some(salts.clone()),
    Some(kdf),
    None,
).unwrap();

// Pack settings + salts + kdf into header; store in ciphertext.
let header = pack(TimePrecision::Hour, TimeFormat::Hour24,
                  &TimeLockCadence::DayOfWeek(Weekday::Tuesday), salts, kdf);

// Decryption side — call on a Tuesday at 18:xx:
let dec_key = timelock(
    None, None, None, None, None, None,
    Some(header),
).unwrap();
// enc_key.as_bytes() == dec_key.as_bytes() when called at the right time