@lelantos-org/sdk / fmd / fmdExpandDetectionKey

Function: fmdExpandDetectionKey()

function fmdExpandDetectionKey(
   J, 
   P, 
   dkRoot, 
   gamma?
): FmdDetectionKey;

Defined in: @lelantos-org/sdk/dist/fmd/fmd.d.ts:87

Expand the root secret into the γ detection scalars, x_i = dk_root + h_i (mod q) — the discrete logs of fmdExpandFlagKey's output. Receiver side.

Must not apply fmdGenDetectionKey's zero-scalar fixup: remapping a zero x_i here and not in the flag key would desynchronise the two halves. A zero x_i (probability ~2^-251) yields a constant clue bit on both sides, which keeps them consistent.

Parameters

Parameter	Type
J	WasmJubjub
P	Poseidon
dkRoot	bigint
gamma?	number

Returns

FmdDetectionKey