fss::HalfTreeDpf< in_bits, Group, Prg, In, par_depth > Class Template Reference

2-party DPF scheme using the Half-Tree construction. More...

Classes
struct	Cw
	Correction word. More...

Public Member Functions
void	Gen (Cw cws[], int4 &ocw, const int4 s0s[2], In a, int4 b_buf)
	Key generation method.
int4	Eval (bool b, int4 s0, const Cw cws[], int4 ocw, In x)
	Evaluation method.
void	EvalAll (bool b, int4 s0, const Cw cws[], int4 ocw, int4 ys[])
	Full domain evaluation method.

Public Attributes
Prg	prg
int4	hash_key

Detailed Description

template<int in_bits, typename Group, typename Prg, typename In = uint, int par_depth = -1>
requires ((std::is_unsigned_v<In> || std::is_same_v<In, __uint128_t>) && in_bits <= sizeof(In) * 8 && Groupable<Group> && Prgable<Prg, 1>)
class fss::HalfTreeDpf< in_bits, Group, Prg, In, par_depth >

2-party DPF scheme using the Half-Tree construction.

Template Parameters

in_bits	Input domain bit size.
Group	Type for the output domain. See Groupable.
Prg	See Prgable. Requires mul=1 (CCR hash, 128->128 bits).
In	Type for the input domain. From uint8_t to __uint128_t.
par_depth	-1 is to use ceil(log(num of threads)), which should be good enough. Only EvalAll() uses it. See EvalAll() for details.

Member Function Documentation

Eval()

template<int in_bits, typename Group , typename Prg , typename In = uint, int par_depth = -1>

int4 fss::HalfTreeDpf< in_bits, Group, Prg, In, par_depth >::Eval ( bool  b, int4  s0, const Cw  cws[], int4  ocw, In  x  )

inline

Evaluation method.

Parameters

b	Party index. False for 0 and true for 1.
s0	Initial seed of the party.
cws	Returned by Gen().
ocw	Output correction word returned by Gen().
x	Evaluated input.

Returns

Output share.

EvalAll()

template<int in_bits, typename Group , typename Prg , typename In = uint, int par_depth = -1>

void fss::HalfTreeDpf< in_bits, Group, Prg, In, par_depth >::EvalAll ( bool  b, int4  s0, const Cw  cws[], int4  ocw, int4  ys[]  )

inline

Full domain evaluation method.

Evaluate the key on each input, i.e., 0b00...0 - 0b11...1.

Parameters

ys	Pre-allocated output array. Its size must be at least 2 ** in_bits.

Support parallel using OpenMP.

Gen()

template<int in_bits, typename Group , typename Prg , typename In = uint, int par_depth = -1>

void fss::HalfTreeDpf< in_bits, Group, Prg, In, par_depth >::Gen ( Cw  cws[], int4 &  ocw, const int4  s0s[2], In  a, int4  b_buf  )

inline

Key generation method.

Parameters

cws	Pre-allocated array of Cw as returns. The array size must be in_bits.
ocw	Output correction word (for the Convert step).
s0s	2 initial seeds. Users can randomly sample them.
a	The special point alpha.
b_buf	The nonzero output value beta. Will be clamped and converted to the group element.

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The documentation for this class was generated from the following file:

• include/fss/half_tree_dpf.cuh