Botan::DH_PublicKey Class Reference

#include <dh.h>

Inheritance diagram for Botan::DH_PublicKey:

Public Member Functions
std::string	algo_name () const override
AlgorithmIdentifier	algorithm_identifier () const override
bool	check_key (RandomNumberGenerator &rng, bool strong) const override
virtual std::unique_ptr< PK_Ops::Encryption >	create_encryption_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const
virtual std::unique_ptr< PK_Ops::KEM_Encryption >	create_kem_encryption_op (std::string_view params, std::string_view provider) const
virtual std::unique_ptr< PK_Ops::Verification >	create_verification_op (std::string_view params, std::string_view provider) const
virtual std::unique_ptr< PK_Ops::Verification >	create_x509_verification_op (const AlgorithmIdentifier &signature_algorithm, std::string_view provider) const
virtual Signature_Format	default_x509_signature_format () const
	DH_PublicKey (const AlgorithmIdentifier &alg_id, std::span< const uint8_t > key_bits)
	DH_PublicKey (const DL_Group &group, const BigInt &y)
size_t	estimated_strength () const override
std::string	fingerprint_public (std::string_view alg="SHA-256") const
const BigInt &	get_int_field (std::string_view field) const override
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 >	public_value () const
std::vector< uint8_t >	subject_public_key () const
bool	supports_operation (PublicKeyOperation op) const override

Friends
class	DH_PrivateKey

Detailed Description

This class represents Diffie-Hellman public keys.

Definition at line 24 of file dh.h.

Constructor & Destructor Documentation

DH_PublicKey() [1/2]

Botan::DH_PublicKey::DH_PublicKey	(	const AlgorithmIdentifier &	alg_id,
		std::span< const uint8_t >	key_bits
	)

Create a public key.

Parameters

alg_id	the X.509 algorithm identifier
key_bits	DER encoded public key bits

Definition at line 15 of file dh.cpp.

   {
   m_public_key = std::make_shared<DL_PublicKey>(alg_id, key_bits, DL_Group_Format::ANSI_X9_42);
   }

References Botan::ANSI_X9_42.

DH_PublicKey() [2/2]

Botan::DH_PublicKey::DH_PublicKey	(	const DL_Group &	group,
		const BigInt &	y
	)

Construct a public key with the specified parameters.

Parameters

group	the DL group to use in the key
y	the public value y

Definition at line 21 of file dh.cpp.

   {
   m_public_key = std::make_shared<DL_PublicKey>(group, y);
   }

References y.

Member Function Documentation

algo_name()

std::string Botan::DH_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 52 of file dh.h.

{ return "DH"; }

Referenced by Botan::DH_PrivateKey::create_key_agreement_op(), get_int_field(), and Botan::DH_PrivateKey::get_int_field().

algorithm_identifier()

AlgorithmIdentifier Botan::DH_PublicKey::algorithm_identifier ( ) const

overridevirtual

Returns

X.509 AlgorithmIdentifier for this key

Implements Botan::Public_Key.

Definition at line 46 of file dh.cpp.

   {
   return AlgorithmIdentifier(
      object_identifier(),
      m_public_key->group().DER_encode(DL_Group_Format::ANSI_X9_42));
   }

References Botan::ANSI_X9_42, and Botan::Asymmetric_Key::object_identifier().

check_key()

bool Botan::DH_PublicKey::check_key ( RandomNumberGenerator &  rng, bool  strong  ) const

overridevirtual

Implements Botan::Public_Key.

Definition at line 58 of file dh.cpp.

   {
   return m_public_key->check_key(rng, strong);
   }

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

rng	a 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.
params	additional parameters
provider	the provider to use

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

Definition at line 102 of file pk_keys.cpp.

   {
   throw Lookup_Error(fmt("{} does not support encryption", algo_name()));
   }

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

params	additional parameters
provider	the provider to use

Reimplemented in Botan::Kyber_PublicKey, Botan::McEliece_PublicKey, and Botan::RSA_PublicKey.

Definition at line 110 of file pk_keys.cpp.

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

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::Public_Key::create_verification_op ( std::string_view  params, std::string_view  provider  ) const

virtualinherited

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

params	additional parameters
provider	the provider to use

Reimplemented in Botan::Dilithium_PublicKey, Botan::DSA_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, Botan::Ed25519_PublicKey, Botan::GOST_3410_PublicKey, Botan::RSA_PublicKey, Botan::SM2_PublicKey, and Botan::XMSS_PublicKey.

Definition at line 117 of file pk_keys.cpp.

   {
   throw Lookup_Error(fmt("{} does not support verification", algo_name()));
   }

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

Referenced by Botan::PK_Verifier::PK_Verifier().

create_x509_verification_op()

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

virtualinherited

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

Reimplemented in Botan::RSA_PublicKey, Botan::XMSS_PublicKey, Botan::Dilithium_PublicKey, Botan::DSA_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, Botan::Ed25519_PublicKey, and Botan::GOST_3410_PublicKey.

Definition at line 124 of file pk_keys.cpp.

   {
   throw Lookup_Error(fmt("{} does not support X.509 verification", algo_name()));
   }

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

Referenced by Botan::PK_Verifier::PK_Verifier().

default_x509_signature_format()

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

inlinevirtualinherited

Reimplemented in Botan::GOST_3410_PublicKey.

Definition at line 184 of file pk_keys.h.

         {
         return (this->message_parts() >= 2) ? Signature_Format::DerSequence : Signature_Format::Standard;
         }

Referenced by Botan::X509_Object::choose_sig_format(), and Botan::PK_Verifier::PK_Verifier().

estimated_strength()

size_t Botan::DH_PublicKey::estimated_strength ( ) const

overridevirtual

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 31 of file dh.cpp.

   {
   return m_public_key->estimated_strength();
   }

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 88 of file pk_keys.cpp.

   {
   return create_hex_fingerprint(subject_public_key(), hash_algo);
   }

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

get_int_field()

const BigInt & Botan::DH_PublicKey::get_int_field ( std::string_view  field ) const

overridevirtual

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 from Botan::Asymmetric_Key.

Reimplemented in Botan::DH_PrivateKey.

Definition at line 41 of file dh.cpp.

   {
   return m_public_key->get_int_field(algo_name(), field);
   }

References algo_name().

get_oid()

OID Botan::Public_Key::get_oid ( ) const

inlineinherited

Deprecated version of object_identifier

Definition at line 122 of file pk_keys.h.

         {
         return this->object_identifier();
         }

key_length()

size_t Botan::DH_PublicKey::key_length ( ) const

overridevirtual

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 36 of file dh.cpp.

   {
   return m_public_key->p_bits();
   }

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 182 of file pk_keys.h.

{ return 0; }

Referenced by Botan::PK_Signer::PK_Signer(), 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 171 of file pk_keys.h.

{ return 1; }

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

object_identifier()

OID Botan::Asymmetric_Key::object_identifier ( ) const

virtualinherited

Get the OID of the underlying public key scheme.

Returns

OID of the public key scheme

Reimplemented in Botan::Dilithium_PublicKey, and Botan::Kyber_PublicKey.

Definition at line 22 of file pk_keys.cpp.

   {
   try
      {
      return OID::from_string(algo_name());
      }
   catch(Lookup_Error&)
      {
      throw Lookup_Error(fmt("Public key algorithm {} has no defined OIDs", algo_name()));
      }
   }

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

Referenced by Botan::TPM_PrivateKey::algorithm_identifier(), Botan::Curve25519_PublicKey::algorithm_identifier(), algorithm_identifier(), Botan::DSA_PublicKey::algorithm_identifier(), Botan::EC_PublicKey::algorithm_identifier(), Botan::Ed25519_PublicKey::algorithm_identifier(), Botan::ElGamal_PublicKey::algorithm_identifier(), Botan::GOST_3410_PublicKey::algorithm_identifier(), Botan::McEliece_PublicKey::algorithm_identifier(), and Botan::RSA_PublicKey::algorithm_identifier().

public_key_bits()

std::vector< uint8_t > Botan::DH_PublicKey::public_key_bits ( ) const

overridevirtual

Returns

BER encoded public key bits

Implements Botan::Public_Key.

Definition at line 53 of file dh.cpp.

   {
   return m_public_key->DER_encode();
   }

public_value()

std::vector< uint8_t > Botan::DH_PublicKey::public_value

(

)

const

Definition at line 26 of file dh.cpp.

   {
   return m_public_key->public_key_as_bytes();
   }

Referenced by Botan::DH_PrivateKey::public_value().

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 55 of file pk_keys.cpp.

   {
   std::vector<uint8_t> output;
 
   DER_Encoder(output).start_sequence()
         .encode(algorithm_identifier())
         .encode(public_key_bits(), ASN1_Type::BitString)
      .end_cons();
 
   return output;
   }

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::DH_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 56 of file dh.h.

         {
         return (op == PublicKeyOperation::KeyAgreement);
         }

Friends And Related Function Documentation

DH_PrivateKey

friend class DH_PrivateKey

friend

Definition at line 61 of file dh.h.

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

• src/lib/pubkey/dh/dh.h
• src/lib/pubkey/dh/dh.cpp