Botan 3.5.0
Crypto and TLS for C&
Botan::XMSS_PublicKey Class Reference

#include <xmss.h>

Inheritance diagram for Botan::XMSS_PublicKey:
Botan::Public_Key Botan::Asymmetric_Key Botan::XMSS_PrivateKey

Public Member Functions

std::string algo_name () const override
 
AlgorithmIdentifier algorithm_identifier () const override
 
bool check_key (RandomNumberGenerator &, bool) const override
 
virtual std::unique_ptr< PK_Ops::Encryptioncreate_encryption_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const
 
virtual std::unique_ptr< PK_Ops::KEM_Encryptioncreate_kem_encryption_op (std::string_view params, std::string_view provider) const
 
std::unique_ptr< PK_Ops::Verificationcreate_verification_op (std::string_view params, std::string_view provider) const override
 
std::unique_ptr< PK_Ops::Verificationcreate_x509_verification_op (const AlgorithmIdentifier &alg_id, std::string_view provider) const override
 
virtual Signature_Format default_x509_signature_format () const
 
size_t estimated_strength () const override
 
std::string fingerprint_public (std::string_view alg="SHA-256") const
 
std::unique_ptr< Private_Keygenerate_another (RandomNumberGenerator &rng) const final
 
virtual const BigIntget_int_field (std::string_view field) const
 
OID get_oid () const
 
size_t key_length () const override
 
virtual size_t message_part_size () const
 
virtual size_t message_parts () const
 
virtual OID object_identifier () const
 
std::vector< uint8_t > public_key_bits () const override
 
std::vector< uint8_t > raw_public_key () const
 
std::vector< uint8_t > raw_public_key_bits () const override
 
std::vector< uint8_t > subject_public_key () const
 
bool supports_operation (PublicKeyOperation op) const override
 
 XMSS_PublicKey (std::span< const uint8_t > key_bits)
 
 XMSS_PublicKey (XMSS_Parameters::xmss_algorithm_t xmss_oid, RandomNumberGenerator &rng)
 
 XMSS_PublicKey (XMSS_Parameters::xmss_algorithm_t xmss_oid, secure_vector< uint8_t > root, secure_vector< uint8_t > public_seed)
 

Protected Member Functions

const secure_vector< uint8_t > & public_seed () const
 
const secure_vector< uint8_t > & root () const
 
const XMSS_Parametersxmss_parameters () const
 

Protected Attributes

secure_vector< uint8_t > m_public_seed
 
std::vector< uint8_t > m_raw_key
 
secure_vector< uint8_t > m_root
 
XMSS_WOTS_Parameters m_wots_params
 
XMSS_Parameters m_xmss_params
 

Friends

class XMSS_Verification_Operation
 

Detailed Description

An XMSS: Extended Hash-Based Signature public key.

[1] XMSS: Extended Hash-Based Signatures, Request for Comments: 8391 Release: May 2018. https://datatracker.ietf.org/doc/rfc8391/

Definition at line 37 of file xmss.h.

Constructor & Destructor Documentation

◆ XMSS_PublicKey() [1/3]

Botan::XMSS_PublicKey::XMSS_PublicKey ( XMSS_Parameters::xmss_algorithm_t xmss_oid,
RandomNumberGenerator & rng )

Creates a new XMSS public key for the chosen XMSS signature method. New public and prf seeds are generated using rng. The appropriate WOTS signature method will be automatically set based on the chosen XMSS signature method.

Parameters
xmss_oidIdentifier for the selected XMSS signature method.
rngA random number generator to use for key generation.

Definition at line 71 of file xmss_publickey.cpp.

71 :
72 m_xmss_params(xmss_oid),
75 m_public_seed(rng.random_vec(m_xmss_params.element_size())) {}
XMSS_WOTS_Parameters::ots_algorithm_t ots_oid() const
size_t element_size() const
secure_vector< uint8_t > m_root
Definition xmss.h:126
secure_vector< uint8_t > m_public_seed
Definition xmss.h:127
XMSS_Parameters m_xmss_params
Definition xmss.h:124
XMSS_WOTS_Parameters m_wots_params
Definition xmss.h:125

◆ XMSS_PublicKey() [2/3]

Botan::XMSS_PublicKey::XMSS_PublicKey ( std::span< const uint8_t > key_bits)

Loads a public key.

Public key must be encoded as in RFC draft-vangeest-x509-hash-sigs-03.

Parameters
key_bitsDER encoded public key bits

Definition at line 77 of file xmss_publickey.cpp.

77 :
78 m_raw_key(extract_raw_public_key(key_bits)),
79 m_xmss_params(deserialize_xmss_oid(m_raw_key)),
82 throw Decoding_Error("Invalid XMSS public key size detected");
83 }
84
85 BufferSlicer s(m_raw_key);
86 s.skip(4 /* algorithm ID -- already consumed by `deserialize_xmss_oid()` */);
87
88 m_root = s.copy_as_secure_vector(m_xmss_params.element_size());
89 m_public_seed = s.copy_as_secure_vector(m_xmss_params.element_size());
90}
size_t raw_public_key_size() const
std::vector< uint8_t > m_raw_key
Definition xmss.h:123

References Botan::BufferSlicer::copy_as_secure_vector(), Botan::XMSS_Parameters::element_size(), m_public_seed, m_raw_key, m_root, m_xmss_params, Botan::XMSS_Parameters::raw_public_key_size(), and Botan::BufferSlicer::skip().

◆ XMSS_PublicKey() [3/3]

Botan::XMSS_PublicKey::XMSS_PublicKey ( XMSS_Parameters::xmss_algorithm_t xmss_oid,
secure_vector< uint8_t > root,
secure_vector< uint8_t > public_seed )

Creates a new XMSS public key for a chosen XMSS signature method as well as pre-computed root node and public_seed values.

Parameters
xmss_oidIdentifier for the selected XMSS signature method.
rootRoot node value.
public_seedPublic seed value.

Definition at line 92 of file xmss_publickey.cpp.

94 :
95 m_xmss_params(xmss_oid),
97 m_root(std::move(root)),
98 m_public_seed(std::move(public_seed)) {
99 BOTAN_ARG_CHECK(m_root.size() == m_xmss_params.element_size(), "XMSS: unexpected byte length of root hash");
100 BOTAN_ARG_CHECK(m_public_seed.size() == m_xmss_params.element_size(), "XMSS: unexpected byte length of public seed");
101}
#define BOTAN_ARG_CHECK(expr, msg)
Definition assert.h:29
const secure_vector< uint8_t > & root() const
Definition xmss.h:118
const secure_vector< uint8_t > & public_seed() const
Definition xmss.h:116

References BOTAN_ARG_CHECK, Botan::XMSS_Parameters::element_size(), m_public_seed, m_root, and m_xmss_params.

Member Function Documentation

◆ algo_name()

std::string Botan::XMSS_PublicKey::algo_name ( ) const
inlineoverridevirtual

Get the name of the underlying public key scheme.

Returns
name of the public key scheme

Implements Botan::Asymmetric_Key.

Definition at line 72 of file xmss.h.

72{ return "XMSS"; }

Referenced by Botan::XMSS_PrivateKey::create_signature_op(), create_verification_op(), and create_x509_verification_op().

◆ algorithm_identifier()

AlgorithmIdentifier Botan::XMSS_PublicKey::algorithm_identifier ( ) const
inlineoverridevirtual
Returns
X.509 AlgorithmIdentifier for this key

Implements Botan::Public_Key.

Definition at line 74 of file xmss.h.

74 {
75 return AlgorithmIdentifier(object_identifier(), AlgorithmIdentifier::USE_EMPTY_PARAM);
76 }
virtual OID object_identifier() const
Definition pk_keys.cpp:22

Referenced by create_x509_verification_op().

◆ check_key()

bool Botan::XMSS_PublicKey::check_key ( RandomNumberGenerator & ,
bool  ) const
inlineoverridevirtual

Implements Botan::Public_Key.

Definition at line 78 of file xmss.h.

78{ return true; }

◆ create_encryption_op()

std::unique_ptr< PK_Ops::Encryption > Botan::Public_Key::create_encryption_op ( RandomNumberGenerator & rng,
std::string_view params,
std::string_view provider ) const
virtualinherited

This is an internal library function exposed on key types. In almost all cases applications should use wrappers in pubkey.h

Return an encryption operation for this key/params or throw

Parameters
rnga random number generator. The PK_Op may maintain a reference to the RNG and use it many times. The rng must outlive any operations which reference it.
paramsadditional parameters
providerthe provider to use

Reimplemented in Botan::ElGamal_PublicKey, Botan::RSA_PublicKey, and Botan::SM2_PublicKey.

Definition at line 90 of file pk_keys.cpp.

92 {
93 throw Lookup_Error(fmt("{} does not support encryption", algo_name()));
94}
virtual std::string algo_name() const =0
std::string fmt(std::string_view format, const T &... args)
Definition fmt.h:53

References Botan::Asymmetric_Key::algo_name(), and Botan::fmt().

Referenced by Botan::PK_Encryptor_EME::PK_Encryptor_EME().

◆ create_kem_encryption_op()

std::unique_ptr< PK_Ops::KEM_Encryption > Botan::Public_Key::create_kem_encryption_op ( std::string_view params,
std::string_view provider ) const
virtualinherited

This is an internal library function exposed on key types. In almost all cases applications should use wrappers in pubkey.h

Return a KEM encryption operation for this key/params or throw

Parameters
paramsadditional parameters
providerthe provider to use

Reimplemented in Botan::FrodoKEM_PublicKey, Botan::Kyber_PublicKey, Botan::McEliece_PublicKey, Botan::RSA_PublicKey, Botan::TLS::Hybrid_KEM_PublicKey, and Botan::TLS::KEX_to_KEM_Adapter_PublicKey.

Definition at line 96 of file pk_keys.cpp.

97 {
98 throw Lookup_Error(fmt("{} does not support KEM encryption", algo_name()));
99}

References Botan::Asymmetric_Key::algo_name(), and Botan::fmt().

Referenced by Botan::PK_KEM_Encryptor::PK_KEM_Encryptor().

◆ create_verification_op()

std::unique_ptr< PK_Ops::Verification > Botan::XMSS_PublicKey::create_verification_op ( std::string_view params,
std::string_view provider ) const
overridevirtual

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return a verification operation for this key/params or throw

Parameters
paramsadditional parameters
providerthe provider to use

Reimplemented from Botan::Public_Key.

Definition at line 103 of file xmss_publickey.cpp.

104 {
105 if(provider == "base" || provider.empty()) {
106 return std::make_unique<XMSS_Verification_Operation>(*this);
107 }
108 throw Provider_Not_Found(algo_name(), provider);
109}
std::string algo_name() const override
Definition xmss.h:72

References algo_name().

◆ create_x509_verification_op()

std::unique_ptr< PK_Ops::Verification > Botan::XMSS_PublicKey::create_x509_verification_op ( const AlgorithmIdentifier & signature_algorithm,
std::string_view provider ) const
overridevirtual

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return a verification operation for this combination of key and signature algorithm or throw.

Parameters
signature_algorithmis the X.509 algorithm identifier encoding the padding scheme and hash hash function used in the signature if applicable.
providerthe provider to use

Reimplemented from Botan::Public_Key.

Definition at line 111 of file xmss_publickey.cpp.

112 {
113 if(provider == "base" || provider.empty()) {
114 if(alg_id != this->algorithm_identifier()) {
115 throw Decoding_Error("Unexpected AlgorithmIdentifier for XMSS X509 signature");
116 }
117 return std::make_unique<XMSS_Verification_Operation>(*this);
118 }
119 throw Provider_Not_Found(algo_name(), provider);
120}
AlgorithmIdentifier algorithm_identifier() const override
Definition xmss.h:74

References algo_name(), and algorithm_identifier().

◆ default_x509_signature_format()

virtual Signature_Format Botan::Public_Key::default_x509_signature_format ( ) const
inlinevirtualinherited

◆ estimated_strength()

size_t Botan::XMSS_PublicKey::estimated_strength ( ) const
inlineoverridevirtual

Return the estimated strength of the underlying key against the best currently known attack. Note that this ignores anything but pure attacks against the key itself and do not take into account padding schemes, usage mistakes, etc which might reduce the strength. However it does suffice to provide an upper bound.

Returns
estimated strength in bits

Implements Botan::Asymmetric_Key.

Definition at line 80 of file xmss.h.

size_t estimated_strength() const

◆ fingerprint_public()

std::string Botan::Public_Key::fingerprint_public ( std::string_view alg = "SHA-256") const
inherited
Returns
Hash of the subject public key

Definition at line 79 of file pk_keys.cpp.

79 {
80 return create_hex_fingerprint(subject_public_key(), hash_algo);
81}
std::vector< uint8_t > subject_public_key() const
Definition pk_keys.cpp:48
std::string create_hex_fingerprint(const uint8_t bits[], size_t bits_len, std::string_view hash_name)
Definition pk_keys.cpp:30

References Botan::create_hex_fingerprint(), and Botan::Public_Key::subject_public_key().

◆ generate_another()

std::unique_ptr< Private_Key > Botan::XMSS_PublicKey::generate_another ( RandomNumberGenerator & rng) const
finalvirtual

Generate another (cryptographically independent) key pair using the same algorithm parameters as this key. This is most useful for algorithms that support PublicKeyOperation::KeyAgreement to generate a fitting ephemeral key pair. For other key types it might throw Not_Implemented.

Implements Botan::Asymmetric_Key.

Definition at line 136 of file xmss_publickey.cpp.

136 {
137 // Note: Given only an XMSS public key we cannot know which WOTS key
138 // derivation method was used to build the XMSS tree. Hence, we have to
139 // use the default here.
140 return std::make_unique<XMSS_PrivateKey>(m_xmss_params.oid(), rng);
141}
xmss_algorithm_t oid() const

References m_xmss_params, and Botan::XMSS_Parameters::oid().

◆ get_int_field()

const BigInt & Botan::Asymmetric_Key::get_int_field ( std::string_view field) const
virtualinherited

Access an algorithm specific field

If the field is not known for this algorithm, an Invalid_Argument is thrown. The interpretation of the result requires knowledge of which algorithm is involved. For instance for RSA "p" represents one of the secret primes, while for DSA "p" is the public prime.

Some algorithms may not implement this method at all.

This is primarily used to implement the FFI botan_pubkey_get_field and botan_privkey_get_field functions.

Reimplemented in Botan::DH_PrivateKey, Botan::DH_PublicKey, Botan::DSA_PrivateKey, Botan::DSA_PublicKey, Botan::EC_PrivateKey, Botan::EC_PublicKey, Botan::ElGamal_PrivateKey, Botan::ElGamal_PublicKey, Botan::RSA_PrivateKey, and Botan::RSA_PublicKey.

Definition at line 18 of file pk_keys.cpp.

18 {
19 throw Unknown_PK_Field_Name(algo_name(), field);
20}

References Botan::Asymmetric_Key::algo_name().

Referenced by Botan::EC_PublicKey::get_int_field(), and Botan::RSA_PublicKey::get_int_field().

◆ get_oid()

OID Botan::Public_Key::get_oid ( ) const
inlineinherited

Deprecated version of object_identifier

Definition at line 132 of file pk_keys.h.

132{ return this->object_identifier(); }

◆ key_length()

size_t Botan::XMSS_PublicKey::key_length ( ) const
inlineoverridevirtual

Return an integer value best approximating the length of the primary security parameter. For example for RSA this will be the size of the modulus, for ECDSA the size of the ECC group, and for McEliece the size of the code will be returned.

Implements Botan::Public_Key.

Definition at line 82 of file xmss.h.

◆ message_part_size()

virtual size_t Botan::Public_Key::message_part_size ( ) const
inlinevirtualinherited

Returns how large each of the message parts refered to by message_parts() is

This function is public but applications should have few reasons to ever call this.

Returns
size of the message parts in bits

Reimplemented in Botan::DSA_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, Botan::GOST_3410_PublicKey, and Botan::SM2_PublicKey.

Definition at line 199 of file pk_keys.h.

199{ return 0; }

Referenced by Botan::PK_Signer::PK_Signer(), Botan::PK_Verifier::PK_Verifier(), and Botan::PK_Verifier::PK_Verifier().

◆ message_parts()

virtual size_t Botan::Public_Key::message_parts ( ) const
inlinevirtualinherited

Returns more than 1 if the output of this algorithm (ciphertext, signature) should be treated as more than one value. This is used for algorithms like DSA and ECDSA, where the (r,s) output pair can be encoded as either a plain binary list or a TLV tagged DER encoding depending on the protocol.

This function is public but applications should have few reasons to ever call this.

Returns
number of message parts

Reimplemented in Botan::DSA_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, Botan::GOST_3410_PublicKey, and Botan::SM2_PublicKey.

Definition at line 188 of file pk_keys.h.

188{ return 1; }

Referenced by Botan::PK_Signer::PK_Signer(), Botan::PK_Verifier::PK_Verifier(), and Botan::PK_Verifier::PK_Verifier().

◆ object_identifier()

◆ public_key_bits()

std::vector< uint8_t > Botan::XMSS_PublicKey::public_key_bits ( ) const
overridevirtual

Returns the encoded public key as defined in RFC draft-vangeest-x509-hash-sigs-03.

Returns
encoded public key bits

Implements Botan::Public_Key.

Definition at line 126 of file xmss_publickey.cpp.

126 {
127 std::vector<uint8_t> output;
128 DER_Encoder(output).encode(raw_public_key_bits(), ASN1_Type::OctetString);
129 return output;
130}
std::vector< uint8_t > raw_public_key_bits() const override

References Botan::DER_Encoder::encode(), Botan::OctetString, and raw_public_key_bits().

◆ public_seed()

const secure_vector< uint8_t > & Botan::XMSS_PublicKey::public_seed ( ) const
inlineprotected

Definition at line 116 of file xmss.h.

116{ return m_public_seed; }

Referenced by Botan::XMSS_PrivateKey::public_key().

◆ raw_public_key()

std::vector< uint8_t > Botan::XMSS_PublicKey::raw_public_key ( ) const

Definition at line 132 of file xmss_publickey.cpp.

132 {
133 return raw_public_key_bits();
134}

References raw_public_key_bits().

Referenced by Botan::XMSS_PrivateKey::raw_private_key().

◆ raw_public_key_bits()

std::vector< uint8_t > Botan::XMSS_PublicKey::raw_public_key_bits ( ) const
overridevirtual

Generates a byte sequence representing the XMSS public key, as defined in [1] (p. 23, "XMSS Public Key")

Returns
4-byte OID, followed by n-byte root node, followed by public seed.

Implements Botan::Public_Key.

Definition at line 122 of file xmss_publickey.cpp.

122 {
123 return concat<std::vector<uint8_t>>(store_be(static_cast<uint32_t>(m_xmss_params.oid())), m_root, m_public_seed);
124}
constexpr auto concat(Rs &&... ranges)
Definition stl_util.h:262
constexpr auto store_be(ParamTs &&... params)
Definition loadstor.h:707

References Botan::concat(), m_public_seed, m_root, m_xmss_params, Botan::XMSS_Parameters::oid(), and Botan::store_be().

Referenced by public_key_bits(), and raw_public_key().

◆ root()

const secure_vector< uint8_t > & Botan::XMSS_PublicKey::root ( ) const
inlineprotected

Definition at line 118 of file xmss.h.

118{ return m_root; }

Referenced by Botan::XMSS_PrivateKey::public_key().

◆ subject_public_key()

std::vector< uint8_t > Botan::Public_Key::subject_public_key ( ) const
inherited
Returns
X.509 subject key encoding for this key object

Definition at line 48 of file pk_keys.cpp.

48 {
49 std::vector<uint8_t> output;
50
51 DER_Encoder(output)
52 .start_sequence()
53 .encode(algorithm_identifier())
55 .end_cons();
56
57 return output;
58}
virtual AlgorithmIdentifier algorithm_identifier() const =0
virtual std::vector< uint8_t > public_key_bits() const =0

References Botan::Public_Key::algorithm_identifier(), Botan::BitString, Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), Botan::Public_Key::public_key_bits(), and Botan::DER_Encoder::start_sequence().

Referenced by Botan::X509::BER_encode(), Botan::PKCS10_Request::create(), Botan::Public_Key::fingerprint_public(), and Botan::X509::PEM_encode().

◆ supports_operation()

bool Botan::XMSS_PublicKey::supports_operation ( PublicKeyOperation op) const
inlineoverridevirtual

Return true if this key could be used for the specified type of operation.

Implements Botan::Asymmetric_Key.

Definition at line 105 of file xmss.h.

◆ xmss_parameters()

const XMSS_Parameters & Botan::XMSS_PublicKey::xmss_parameters ( ) const
inlineprotected

Friends And Related Symbol Documentation

◆ XMSS_Verification_Operation

friend class XMSS_Verification_Operation
friend

Definition at line 114 of file xmss.h.

Member Data Documentation

◆ m_public_seed

secure_vector<uint8_t> Botan::XMSS_PublicKey::m_public_seed
protected

Definition at line 127 of file xmss.h.

Referenced by raw_public_key_bits(), XMSS_PublicKey(), and XMSS_PublicKey().

◆ m_raw_key

std::vector<uint8_t> Botan::XMSS_PublicKey::m_raw_key
protected

Definition at line 123 of file xmss.h.

Referenced by XMSS_PublicKey().

◆ m_root

secure_vector<uint8_t> Botan::XMSS_PublicKey::m_root
protected

◆ m_wots_params

XMSS_WOTS_Parameters Botan::XMSS_PublicKey::m_wots_params
protected

Definition at line 125 of file xmss.h.

◆ m_xmss_params


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