Botan::CRYSTALS::BitPackingTrait< range, PolyTrait > Struct Template Reference

#include <pqcrystals_encoding.h>

Public Types
using	collector_array = std::array<sink_t, collectors_per_pack>
using	collector_bytearray = std::array<uint8_t, collector_bytes_per_pack>
using	sink_t = uint64_t
using	T = typename PolyTrait::T
using	unsigned_T = std::make_unsigned_t<T>

Static Public Attributes
static constexpr size_t	bits_in_collector = sizeof(sink_t) * 8
static constexpr size_t	bits_per_coeff = bitlen(range)
static constexpr size_t	bits_per_pack
static constexpr size_t	bytes_per_pack = bits_per_pack / 8
static constexpr size_t	coeffs_per_pack = bits_per_pack / bits_per_coeff
static constexpr size_t	collector_bytes_per_pack = collectors_per_pack * sizeof(sink_t)
static constexpr size_t	collectors_per_pack = (bytes_per_pack + sizeof(sink_t) - 1) / sizeof(sink_t)
static constexpr sink_t	value_mask = (1 << bits_per_coeff) - 1

Detailed Description

template<int32_t range, crystals_trait PolyTrait>
struct Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >

Helper for base implementations of NIST FIPS 204, Algorithms 16-19 and NIST FIPS 203 Algorithms 5-6. It pre-computes generic values to bit-(un)pack polynomial coefficients at compile-time.

The base implementations are also templated with the range parameter forcing the compiler to generate specialized code for each supported range.

Definition at line 66 of file pqcrystals_encoding.h.

Member Typedef Documentation

collector_array

template<int32_t range, crystals_trait PolyTrait>

using Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::collector_array = std::array<sink_t, collectors_per_pack>

Definition at line 89 of file pqcrystals_encoding.h.

collector_bytearray

template<int32_t range, crystals_trait PolyTrait>

using Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::collector_bytearray = std::array<uint8_t, collector_bytes_per_pack>

Definition at line 90 of file pqcrystals_encoding.h.

sink_t

template<int32_t range, crystals_trait PolyTrait>

using Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::sink_t = uint64_t

Definition at line 69 of file pqcrystals_encoding.h.

T

template<int32_t range, crystals_trait PolyTrait>

using Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::T = typename PolyTrait::T

Definition at line 67 of file pqcrystals_encoding.h.

unsigned_T

template<int32_t range, crystals_trait PolyTrait>

using Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::unsigned_T = std::make_unsigned_t<T>

Definition at line 68 of file pqcrystals_encoding.h.

Member Data Documentation

bits_in_collector

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::bits_in_collector = sizeof(sink_t) * 8

staticconstexpr

Definition at line 73 of file pqcrystals_encoding.h.

bits_per_coeff

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::bits_per_coeff = bitlen(range)

staticconstexpr

Definition at line 74 of file pqcrystals_encoding.h.

bits_per_pack

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::bits_per_pack

staticconstexpr

Initial value:

= [] {
         
         
         size_t smallest_aligned_pack = std::lcm(bits_per_coeff, size_t(8));
         return (smallest_aligned_pack < bits_in_collector)
                   ? (bits_in_collector / smallest_aligned_pack) * smallest_aligned_pack
                   : smallest_aligned_pack;
      }()

Definition at line 75 of file pqcrystals_encoding.h.

                                                 {
         // Ensure that the bit-packing is byte-aligned and scale it
         // to utilize the collector's bit-width as much as possible.
         size_t smallest_aligned_pack = std::lcm(bits_per_coeff, size_t(8));
         return (smallest_aligned_pack < bits_in_collector)
                   ? (bits_in_collector / smallest_aligned_pack) * smallest_aligned_pack
                   : smallest_aligned_pack;
      }();

bytes_per_pack

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::bytes_per_pack = bits_per_pack / 8

staticconstexpr

Definition at line 83 of file pqcrystals_encoding.h.

coeffs_per_pack

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::coeffs_per_pack = bits_per_pack / bits_per_coeff

staticconstexpr

Definition at line 84 of file pqcrystals_encoding.h.

collector_bytes_per_pack

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::collector_bytes_per_pack = collectors_per_pack * sizeof(sink_t)

staticconstexpr

Definition at line 86 of file pqcrystals_encoding.h.

collectors_per_pack

template<int32_t range, crystals_trait PolyTrait>

size_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::collectors_per_pack = (bytes_per_pack + sizeof(sink_t) - 1) / sizeof(sink_t)

staticconstexpr

Definition at line 85 of file pqcrystals_encoding.h.

value_mask

template<int32_t range, crystals_trait PolyTrait>

sink_t Botan::CRYSTALS::BitPackingTrait< range, PolyTrait >::value_mask = (1 << bits_per_coeff) - 1

staticconstexpr

Definition at line 87 of file pqcrystals_encoding.h.

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

• src/lib/pubkey/pqcrystals/pqcrystals_encoding.h