Botan::BufferStuffer Class Reference

Helper class to ease in-place marshalling of concatenated fixed-length values. More...

#include <stl_util.h>

Public Member Functions
constexpr void	append (std::span< const uint8_t > buffer)
constexpr void	append (uint8_t b, size_t repeat=1)
constexpr	BufferStuffer (std::span< uint8_t > buffer)
constexpr bool	full () const
template<size_t bytes>
constexpr std::span< uint8_t, bytes >	next ()
template<concepts::contiguous_strong_type StrongT>
StrongSpan< StrongT >	next (size_t bytes)
constexpr std::span< uint8_t >	next (size_t bytes)
constexpr uint8_t &	next_byte ()
constexpr size_t	remaining_capacity () const

Detailed Description

Helper class to ease in-place marshalling of concatenated fixed-length values.

The size of the final buffer must be known from the start, reallocations are not performed.

Definition at line 133 of file stl_util.h.

Constructor & Destructor Documentation

BufferStuffer()

Botan::BufferStuffer::BufferStuffer ( std::span< uint8_t > buffer )

inlineexplicitconstexpr

Definition at line 135 of file stl_util.h.

: m_buffer(buffer) {}

Member Function Documentation

append() [1/2]

void Botan::BufferStuffer::append ( std::span< const uint8_t > buffer )

inlineconstexpr

Definition at line 168 of file stl_util.h.

                                                           {
         auto sink = next(buffer.size());
         std::copy(buffer.begin(), buffer.end(), sink.begin());
      }

References next().

Referenced by Botan::KEM_Encryption_with_Combiner::combine_ciphertexts(), Botan::create_aes_row_generator(), Botan::EC_Point::encode(), Botan::Dilithium_Algos::encode_public_key(), Botan::Dilithium_Algos::encode_signature(), Botan::CRYSTALS::pack(), Botan::EC_AffinePoint_Data_BN::serialize_compressed_to(), Botan::EC_AffinePoint_Data_PC::serialize_compressed_to(), Botan::EC_AffinePoint_Data_BN::serialize_uncompressed_to(), Botan::HSS_LMS_PrivateKeyInternal::sign(), Botan::LMOTS_Private_Key::sign(), Botan::LMS_PrivateKey::sign_and_get_pk(), Botan::sign_message(), Botan::HSS_LMS_PrivateKeyInternal::to_bytes(), Botan::TPM2::Context::vendor(), Botan::detail::FullWordBounds< SpongeT >::write_into(), and Botan::detail::PartialWordBounds< SpongeT >::write_into().

append() [2/2]

void Botan::BufferStuffer::append ( uint8_t b, size_t repeat = 1 )

inlineconstexpr

Definition at line 173 of file stl_util.h.

                                                          {
         auto sink = next(repeat);
         std::fill(sink.begin(), sink.end(), b);
      }

References next().

full()

bool Botan::BufferStuffer::full ( ) const

inlineconstexpr

Definition at line 178 of file stl_util.h.

{ return m_buffer.empty(); }

Referenced by Botan::KEM_Encryption_with_Combiner::combine_ciphertexts(), Botan::Kyber_Algos::compress_ciphertext(), Botan::create_aes_row_generator(), Botan::Kyber_Algos::encode_polynomial_vector(), Botan::Dilithium_Algos::encode_public_key(), Botan::fors_public_key_from_signature(), Botan::fors_sign_and_pkgen(), Botan::ht_sign(), Botan::Ascon_p::percolate_in(), Botan::Ascon_p::percolate_out(), Botan::Classic_McEliece_Encryptor::raw_kem_encrypt(), Botan::Classic_McEliece_Minimal_Polynomial::serialize(), Botan::HSS_LMS_PrivateKeyInternal::sign(), Botan::LMOTS_Private_Key::sign(), Botan::LMS_PrivateKey::sign_and_get_pk(), Botan::sign_message(), Botan::squeeze_from_sponge(), and Botan::HSS_LMS_PrivateKeyInternal::to_bytes().

next() [1/3]

template<size_t bytes>

std::span< uint8_t, bytes > Botan::BufferStuffer::next ( )

inlineconstexpr

Definition at line 150 of file stl_util.h.

                                               {
         BOTAN_STATE_CHECK(m_buffer.size() >= bytes);
 
         auto result = m_buffer.first<bytes>();
         m_buffer = m_buffer.subspan(bytes);
         return result;
      }

References BOTAN_STATE_CHECK.

Referenced by append(), append(), next(), and next_byte().

next() [2/3]

template<concepts::contiguous_strong_type StrongT>

StrongSpan< StrongT > Botan::BufferStuffer::next ( size_t bytes )

inline

Definition at line 159 of file stl_util.h.

                                             {
         return StrongSpan<StrongT>(next(bytes));
      }

References next().

next() [3/3]

std::span< uint8_t > Botan::BufferStuffer::next ( size_t bytes )

inlineconstexpr

Returns

a span for the next bytes bytes in the concatenated buffer. Checks that the buffer is not exceeded.

Definition at line 141 of file stl_util.h.

                                                    {
         BOTAN_STATE_CHECK(m_buffer.size() >= bytes);
 
         auto result = m_buffer.first(bytes);
         m_buffer = m_buffer.subspan(bytes);
         return result;
      }

References BOTAN_STATE_CHECK.

Referenced by Botan::Kyber_Algos::compress_ciphertext(), Botan::create_aes_row_generator(), Botan::EC_Point::encode(), Botan::BigInt::encode_fixed_length_int_pair(), Botan::fors_public_key_from_signature(), Botan::fors_sign_and_pkgen(), Botan::ht_sign(), Botan::Classic_McEliece_Encryptor::raw_kem_encrypt(), Botan::Classic_McEliece_Minimal_Polynomial::serialize(), Botan::EC_AffinePoint_Data_BN::serialize_compressed_to(), Botan::EC_AffinePoint_Data_PC::serialize_compressed_to(), Botan::HSS_LMS_PrivateKeyInternal::sign(), Botan::LMOTS_Private_Key::sign(), Botan::LMS_PrivateKey::sign_and_get_pk(), Botan::wots_public_key_from_signature(), Botan::wots_sign_and_pkgen(), and Botan::xmss_sign_and_pkgen().

next_byte()

uint8_t & Botan::BufferStuffer::next_byte ( )

inlineconstexpr

Returns

a reference to the next single byte in the buffer

Definition at line 166 of file stl_util.h.

{ return next(1)[0]; }

References next().

remaining_capacity()

size_t Botan::BufferStuffer::remaining_capacity ( ) const

inlineconstexpr

Definition at line 180 of file stl_util.h.

{ return m_buffer.size(); }

Referenced by Botan::create_aes_row_generator(), Botan::CRYSTALS::pack(), Botan::TPM2::Context::vendor(), and Botan::xmss_sign_and_pkgen().

---

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

• src/lib/utils/stl_util.h