#include <xmss_wots_parameters.h>

Public Types
enum	ots_algorithm_t { WOTSP_SHA2_256 = 0x00000001, WOTSP_SHA2_512 = 0x00000002, WOTSP_SHAKE_256 = 0x00000003, WOTSP_SHAKE_512 = 0x00000004 }

Public Member Functions
void	append_checksum (secure_vector< uint8_t > &data)

secure_vector< uint8_t >	base_w (const secure_vector< uint8_t > &msg, size_t out_size) const

secure_vector< uint8_t >	base_w (size_t value) const

size_t	element_size () const

size_t	estimated_strength () const

const std::string &	hash_function_name () const

size_t	len () const

size_t	len_1 () const

size_t	len_2 () const

size_t	lg_w () const

const std::string &	name () const

ots_algorithm_t	oid () const

bool	operator== (const XMSS_WOTS_Parameters &p) const

size_t	wots_parameter () const

	XMSS_WOTS_Parameters (const std::string &algo_name)

	XMSS_WOTS_Parameters (ots_algorithm_t ots_spec)

Static Public Member Functions
static ots_algorithm_t	xmss_wots_id_from_string (const std::string &param_set)

Detailed Description

Descibes a signature method for XMSS Winternitz One Time Signatures, as defined in: [1] XMSS: Extended Hash-Based Signatures, Request for Comments: 8391 Release: May 2018. https://datatracker.ietf.org/doc/rfc8391/

Definition at line 26 of file xmss_wots_parameters.h.

Member Enumeration Documentation

enum Botan::XMSS_WOTS_Parameters::ots_algorithm_t

Enumerator
WOTSP_SHA2_256
WOTSP_SHA2_512
WOTSP_SHAKE_256
WOTSP_SHAKE_512

Definition at line 29 of file xmss_wots_parameters.h.

          {
          WOTSP_SHA2_256 = 0x00000001,
          WOTSP_SHA2_512 = 0x00000002,
          WOTSP_SHAKE_256 = 0x00000003,
          WOTSP_SHAKE_512 = 0x00000004
          };

Constructor & Destructor Documentation

Botan::XMSS_WOTS_Parameters::XMSS_WOTS_Parameters ( const std::string & algo_name )

Definition at line 35 of file xmss_wots_parameters.cpp.

36 : XMSS_WOTS_Parameters(xmss_wots_id_from_string(param_set))

37 {}

Botan::XMSS_WOTS_Parameters::xmss_wots_id_from_string

static ots_algorithm_t xmss_wots_id_from_string(const std::string &param_set)

Definition: xmss_wots_parameters.cpp:22

Botan::XMSS_WOTS_Parameters::XMSS_WOTS_Parameters

XMSS_WOTS_Parameters(const std::string &algo_name)

Definition: xmss_wots_parameters.cpp:35

Botan::XMSS_WOTS_Parameters::XMSS_WOTS_Parameters ( ots_algorithm_t ots_spec )

Definition at line 39 of file xmss_wots_parameters.cpp.

References BOTAN_ASSERT, element_size(), wots_parameter(), WOTSP_SHA2_256, WOTSP_SHA2_512, WOTSP_SHAKE_256, and WOTSP_SHAKE_512.

    : m_oid(oid)
    {
    switch(oid)
       {
       case WOTSP_SHA2_256:
          m_element_size = 32;
          m_w = 16;
          m_len = 67;
          m_name = "WOTSP-SHA2_256";
          m_hash_name = "SHA-256";
          m_strength = 256;
          break;
       case WOTSP_SHA2_512:
          m_element_size = 64;
          m_w = 16;
          m_len = 131;
          m_name = "WOTSP-SHA2_512";
          m_hash_name = "SHA-512";
          m_strength = 512;
          break;
       case WOTSP_SHAKE_256:
          m_element_size = 32;
          m_w = 16;
          m_len = 67;
          m_name = "WOTSP-SHAKE_256";
          m_hash_name = "SHAKE-128(256)";
          m_strength = 256;
          break;
       case WOTSP_SHAKE_512:
          m_element_size = 64;
          m_w = 16;
          m_len = 131;
          m_name = "WOTSP-SHAKE_512";
          m_hash_name = "SHAKE-256(512)";
          m_strength = 512;
          break;
       default:
          throw Not_Implemented("Algorithm id does not match any known XMSS WOTS algorithm id.");
          break;
       }
 
    m_lg_w = (m_w == 16) ? 4 : 2;
    m_len_1 = static_cast<size_t>(std::ceil((8 * element_size()) / m_lg_w));
    m_len_2 = static_cast<size_t>(
                 floor(log2(m_len_1 * (wots_parameter() - 1)) / m_lg_w) + 1);
    BOTAN_ASSERT(m_len == m_len_1 + m_len_2, "Invalid XMSS WOTS parameter "
                 "\"len\" detedted.");
    }

Member Function Documentation

void Botan::XMSS_WOTS_Parameters::append_checksum ( secure_vector< uint8_t > & data )

Definition at line 123 of file xmss_wots_parameters.cpp.

References base_w(), and wots_parameter().

Referenced by Botan::XMSS_WOTS_PrivateKey::sign().

    {
    size_t csum = 0;
 
    for(size_t i = 0; i < data.size(); i++)
       {
       csum += wots_parameter() - 1 - data[i];
       }
 
    secure_vector<uint8_t> csum_bytes = base_w(csum);
    std::move(csum_bytes.begin(), csum_bytes.end(), std::back_inserter(data));
    }

secure_vector< uint8_t > Botan::XMSS_WOTS_Parameters::base_w	(	const secure_vector< uint8_t > &	msg,
		size_t	out_size
	)		const

Algorithm 1: convert input string to base.

Parameters

msg	Input string (referred to as X in [1]).
out_size	size of message in base w.

Returns: Input string converted to the given base.

Definition at line 90 of file xmss_wots_parameters.cpp.

Referenced by append_checksum(), base_w(), and Botan::XMSS_WOTS_PrivateKey::sign().

    {
    secure_vector<uint8_t> result;
    size_t in = 0;
    size_t total = 0;
    size_t bits = 0;
 
    for(size_t i = 0; i < out_size; i++)
       {
       if(bits == 0)
          {
          total = msg[in];
          in++;
          bits += 8;
          }
       bits -= m_lg_w;
       result.push_back(static_cast<uint8_t>((total >> bits) & (m_w - 1)));
       }
    return result;
    }

secure_vector< uint8_t > Botan::XMSS_WOTS_Parameters::base_w ( size_t value ) const

Definition at line 112 of file xmss_wots_parameters.cpp.

References base_w(), and Botan::XMSS_Tools::concat().

    {
    value <<= (8 - ((m_len_2 * m_lg_w) % 8));
    size_t len_2_bytes = static_cast<size_t>(
                            std::ceil(static_cast<float>(m_len_2 * m_lg_w) / 8.f));
    secure_vector<uint8_t> result;
    XMSS_Tools::concat(result, value, len_2_bytes);
    return base_w(result, m_len_2);
    }

size_t Botan::XMSS_WOTS_Parameters::element_size ( ) const

inline

Retrieves the uniform length of a message, and the size of each node. This correlates to XMSS parameter "n" defined in [1].

Returns: element length in bytes.

Definition at line 79 of file xmss_wots_parameters.h.

Referenced by Botan::XMSS_WOTS_PrivateKey::at(), Botan::XMSS_PrivateKey::XMSS_PrivateKey(), and XMSS_WOTS_Parameters().

79 { return m_element_size; }

size_t Botan::XMSS_WOTS_Parameters::estimated_strength ( ) const

inline

Definition at line 99 of file xmss_wots_parameters.h.

Referenced by Botan::XMSS_WOTS_PublicKey::estimated_strength(), and Botan::XMSS_WOTS_PublicKey::key_length().

99 { return m_strength; }

const std::string& Botan::XMSS_WOTS_Parameters::hash_function_name ( ) const

inline

Returns: Botan name for the hash function used.

Definition at line 67 of file xmss_wots_parameters.h.

          {
          return m_hash_name;
          }

size_t Botan::XMSS_WOTS_Parameters::len ( ) const

inline

Definition at line 89 of file xmss_wots_parameters.h.

Referenced by Botan::XMSS_WOTS_PrivateKey::generate_public_key(), and Botan::XMSS_WOTS_PrivateKey::sign().

89 { return m_len; }

size_t Botan::XMSS_WOTS_Parameters::len_1 ( ) const

inline

Definition at line 91 of file xmss_wots_parameters.h.

Referenced by Botan::XMSS_WOTS_PrivateKey::sign().

91 { return m_len_1; }

size_t Botan::XMSS_WOTS_Parameters::len_2 ( ) const

inline

Definition at line 93 of file xmss_wots_parameters.h.

93 { return m_len_2; }

size_t Botan::XMSS_WOTS_Parameters::lg_w ( ) const

inline

Definition at line 95 of file xmss_wots_parameters.h.

95 { return m_lg_w; }

const std::string& Botan::XMSS_WOTS_Parameters::name ( ) const

inline

Returns: XMSS WOTS registry name for the chosen parameter set.

Definition at line 59 of file xmss_wots_parameters.h.

Referenced by Botan::XMSS_WOTS_PublicKey::algo_name().

          {
          return m_name;
          }

ots_algorithm_t Botan::XMSS_WOTS_Parameters::oid ( ) const

inline

Definition at line 97 of file xmss_wots_parameters.h.

Referenced by Botan::XMSS_WOTS_PrivateKey::generate_public_key().

97 { return m_oid; }

bool Botan::XMSS_WOTS_Parameters::operator== ( const XMSS_WOTS_Parameters & p ) const

inline

Definition at line 101 of file xmss_wots_parameters.h.

          {
          return m_oid == p.m_oid;
          }

size_t Botan::XMSS_WOTS_Parameters::wots_parameter ( ) const

inline

The Winternitz parameter.

Returns: numeric base used for internal representation of data.

Definition at line 87 of file xmss_wots_parameters.h.

Referenced by append_checksum(), Botan::XMSS_WOTS_PublicKey::chain(), Botan::XMSS_WOTS_PrivateKey::generate_public_key(), and XMSS_WOTS_Parameters().

87 { return m_w; }

XMSS_WOTS_Parameters::ots_algorithm_t Botan::XMSS_WOTS_Parameters::xmss_wots_id_from_string ( const std::string & param_set )

static

Definition at line 22 of file xmss_wots_parameters.cpp.

References WOTSP_SHA2_256, WOTSP_SHA2_512, WOTSP_SHAKE_256, and WOTSP_SHAKE_512.

    {
    if(param_set == "WOTSP-SHA2_256")
       { return WOTSP_SHA2_256; }
    if(param_set == "WOTSP-SHA2_512")
       { return WOTSP_SHA2_512; }
    if(param_set == "WOTSP-SHAKE_256")
       { return WOTSP_SHAKE_256; }
    if(param_set == "WOTSP-SHAKE_512")
       { return WOTSP_SHAKE_512; }
    throw Invalid_Argument("Unknown XMSS-WOTS algorithm param '" + param_set + "'");
    }

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

src/lib/pubkey/xmss/xmss_wots_parameters.h
src/lib/pubkey/xmss/xmss_wots_parameters.cpp

Public Types

Public Member Functions

Static Public Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation