Botan::DSA_PublicKey Class Reference

#include <dsa.h>

Inheritance diagram for Botan::DSA_PublicKey:

Public Member Functions
std::string	algo_name () const override
AlgorithmIdentifier	algorithm_identifier () const override
bool	check_key (RandomNumberGenerator &rng, bool) const override
virtual std::unique_ptr< PK_Ops::Encryption >	create_encryption_op (RandomNumberGenerator &rng, const std::string &params, const std::string &provider) const
virtual std::unique_ptr< PK_Ops::KEM_Encryption >	create_kem_encryption_op (RandomNumberGenerator &rng, const std::string &params, const std::string &provider) const
std::unique_ptr< PK_Ops::Verification >	create_verification_op (const std::string &params, const std::string &provider) const override
	DSA_PublicKey (const AlgorithmIdentifier &alg_id, const std::vector< uint8_t > &key_bits)
	DSA_PublicKey (const DL_Group &group, const BigInt &y)
size_t	estimated_strength () const override
std::string	fingerprint_public (const std::string &alg="SHA-256") const
const DL_Group &	get_domain () const
const DL_Group &	get_group () const
virtual OID	get_oid () const
const BigInt &	get_y () const
DL_Group::Format	group_format () const override
const BigInt &	group_g () const
const BigInt &	group_p () const
const BigInt &	group_q () const
size_t	key_length () const override
size_t	message_part_size () const override
size_t	message_parts () const override
std::vector< uint8_t >	public_key_bits () const override
std::vector< uint8_t >	subject_public_key () const

Protected Member Functions
	DSA_PublicKey ()=default

Protected Attributes
DL_Group	m_group
BigInt	m_y

Detailed Description

DSA Public Key

Definition at line 18 of file dsa.h.

Constructor & Destructor Documentation

DSA_PublicKey() [1/3]

Botan::DSA_PublicKey::DSA_PublicKey ( const AlgorithmIdentifier &  alg_id, const std::vector< uint8_t > &  key_bits  )

inline

Load a public key.

Parameters

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

Definition at line 32 of file dsa.h.

                                                        :
         DL_Scheme_PublicKey(alg_id, key_bits, DL_Group::ANSI_X9_57)
         {
         }

DSA_PublicKey() [2/3]

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

Create a public key.

Parameters

group	the underlying DL group
y	the public value y = g^x mod p

Definition at line 26 of file dsa.cpp.

References Botan::DL_Scheme_PublicKey::m_group, and Botan::DL_Scheme_PublicKey::m_y.

   {
   m_group = grp;
   m_y = y1;
   }

DSA_PublicKey() [3/3]

Botan::DSA_PublicKey::DSA_PublicKey ( )

protecteddefault

Member Function Documentation

algo_name()

std::string Botan::DSA_PublicKey::algo_name ( ) const

inlineoverridevirtual

Get the name of the underlying public key scheme.

Returns

name of the public key scheme

Implements Botan::Public_Key.

Definition at line 21 of file dsa.h.

Referenced by Botan::DSA_PrivateKey::create_signature_op(), and create_verification_op().

{ return "DSA"; }

algorithm_identifier()

AlgorithmIdentifier Botan::DL_Scheme_PublicKey::algorithm_identifier ( ) const

overridevirtualinherited

Returns

X.509 AlgorithmIdentifier for this key

Implements Botan::Public_Key.

Definition at line 25 of file dl_algo.cpp.

References Botan::DL_Group::DER_encode(), Botan::Public_Key::get_oid(), Botan::DL_Scheme_PublicKey::group_format(), and Botan::DL_Scheme_PublicKey::m_group.

   {
   return AlgorithmIdentifier(get_oid(),
                              m_group.DER_encode(group_format()));
   }

check_key()

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

overridevirtualinherited

Test the key values for consistency.

Parameters

rng	rng to use
strong	whether to perform strong and lengthy version of the test

Returns

true if the test is passed

Implements Botan::Public_Key.

Reimplemented in Botan::DL_Scheme_PrivateKey, Botan::DSA_PrivateKey, and Botan::ElGamal_PrivateKey.

Definition at line 69 of file dl_algo.cpp.

References Botan::DL_Scheme_PublicKey::m_group, Botan::DL_Scheme_PublicKey::m_y, Botan::DL_Group::verify_group(), and Botan::DL_Group::verify_public_element().

   {
   return m_group.verify_group(rng, strong) && m_group.verify_public_element(m_y);
   }

create_encryption_op()

std::unique_ptr< PK_Ops::Encryption > Botan::Public_Key::create_encryption_op ( RandomNumberGenerator &  rng, const std::string &  params, const std::string &  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::RSA_PublicKey, Botan::SM2_PublicKey, and Botan::ElGamal_PublicKey.

Definition at line 94 of file pk_keys.cpp.

References Botan::Public_Key::algo_name().

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

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

create_kem_encryption_op()

std::unique_ptr< PK_Ops::KEM_Encryption > Botan::Public_Key::create_kem_encryption_op ( RandomNumberGenerator &  rng, const std::string &  params, const std::string &  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

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::RSA_PublicKey, and Botan::McEliece_PublicKey.

Definition at line 102 of file pk_keys.cpp.

References Botan::Public_Key::algo_name().

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

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

create_verification_op()

std::unique_ptr< PK_Ops::Verification > Botan::DSA_PublicKey::create_verification_op ( const std::string &  params, const std::string &  provider  ) const

overridevirtual

This is an internal library function exposed on key types. In almost 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 from Botan::Public_Key.

Definition at line 212 of file dsa.cpp.

References algo_name().

   {
   if(provider == "base" || provider.empty())
      return std::unique_ptr<PK_Ops::Verification>(new DSA_Verification_Operation(*this, params));
   throw Provider_Not_Found(algo_name(), provider);
   }

estimated_strength()

size_t Botan::DL_Scheme_PublicKey::estimated_strength ( ) const

overridevirtualinherited

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::Public_Key.

Definition at line 20 of file dl_algo.cpp.

References Botan::DL_Group::estimated_strength(), and Botan::DL_Scheme_PublicKey::m_group.

   {
   return m_group.estimated_strength();
   }

fingerprint_public()

std::string Botan::Public_Key::fingerprint_public ( const std::string &  alg = "SHA-256" ) const

inherited

Returns

Hash of the subject public key

Definition at line 80 of file pk_keys.cpp.

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

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

get_domain()

const DL_Group& Botan::DL_Scheme_PublicKey::get_domain ( ) const

inlineinherited

Get the DL domain parameters of this key.

Returns

DL domain parameters of this key

Definition at line 32 of file dl_algo.h.

{ return m_group; }

get_group()

const DL_Group& Botan::DL_Scheme_PublicKey::get_group ( ) const

inlineinherited

Get the DL domain parameters of this key.

Returns

DL domain parameters of this key

Definition at line 38 of file dl_algo.h.

Referenced by Botan::DSA_PrivateKey::check_key().

{ return m_group; }

get_oid()

OID Botan::Public_Key::get_oid ( ) const

virtualinherited

Get the OID of the underlying public key scheme.

Returns

OID of the public key scheme

Reimplemented in Botan::XMSS_WOTS_Addressed_PublicKey.

Definition at line 53 of file pk_keys.cpp.

References Botan::Public_Key::algo_name(), and Botan::OIDS::lookup().

Referenced by Botan::DL_Scheme_PublicKey::algorithm_identifier(), Botan::Curve25519_PublicKey::algorithm_identifier(), Botan::Ed25519_PublicKey::algorithm_identifier(), Botan::McEliece_PublicKey::algorithm_identifier(), Botan::RSA_PublicKey::algorithm_identifier(), Botan::GOST_3410_PublicKey::algorithm_identifier(), Botan::EC_PublicKey::algorithm_identifier(), Botan::TPM_PrivateKey::algorithm_identifier(), and Botan::XMSS_WOTS_Addressed_PublicKey::get_oid().

   {
   try {
      return OIDS::lookup(algo_name());
      }
   catch(Lookup_Error&)
      {
      throw Lookup_Error("PK algo " + algo_name() + " has no defined OIDs");
      }
   }

get_y()

const BigInt& Botan::DL_Scheme_PublicKey::get_y ( ) const

inlineinherited

Get the public value y with y = g^x mod p where x is the secret key.

Definition at line 43 of file dl_algo.h.

{ return m_y; }

group_format()

DL_Group::Format Botan::DSA_PublicKey::group_format ( ) const

inlineoverridevirtual

Get the underlying groups encoding format.

Returns

encoding format

Implements Botan::DL_Scheme_PublicKey.

Definition at line 23 of file dsa.h.

References Botan::DL_Group::ANSI_X9_57.

{ return DL_Group::ANSI_X9_57; }

group_g()

const BigInt& Botan::DL_Scheme_PublicKey::group_g ( ) const

inlineinherited

Get the generator g of the underlying DL group.

Returns

generator g

Definition at line 61 of file dl_algo.h.

{ return m_group.get_g(); }

group_p()

const BigInt& Botan::DL_Scheme_PublicKey::group_p ( ) const

inlineinherited

Get the prime p of the underlying DL group.

Returns

prime p

Definition at line 49 of file dl_algo.h.

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

{ return m_group.get_p(); }

group_q()

const BigInt& Botan::DL_Scheme_PublicKey::group_q ( ) const

inlineinherited

Get the prime q of the underlying DL group.

Returns

prime q

Definition at line 55 of file dl_algo.h.

Referenced by Botan::DSA_PrivateKey::check_key().

{ return m_group.get_q(); }

key_length()

size_t Botan::DL_Scheme_PublicKey::key_length ( ) const

overridevirtualinherited

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 15 of file dl_algo.cpp.

References Botan::DL_Scheme_PublicKey::m_group, and Botan::DL_Group::p_bits().

   {
   return m_group.p_bits();
   }

message_part_size()

size_t Botan::DSA_PublicKey::message_part_size ( ) const

inlineoverridevirtual

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 from Botan::Public_Key.

Definition at line 25 of file dsa.h.

{ return group_q().bytes(); }

message_parts()

size_t Botan::DSA_PublicKey::message_parts ( ) const

inlineoverridevirtual

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 from Botan::Public_Key.

Definition at line 24 of file dsa.h.

{ return 2; }

public_key_bits()

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

overridevirtualinherited

Returns

BER encoded public key bits

Implements Botan::Public_Key.

Definition at line 31 of file dl_algo.cpp.

References Botan::DER_Encoder::encode(), and Botan::DL_Scheme_PublicKey::m_y.

   {
   std::vector<uint8_t> output;
   DER_Encoder(output).encode(m_y);
   return output;
   }

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 38 of file pk_keys.cpp.

References Botan::Public_Key::algorithm_identifier(), Botan::BIT_STRING, Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), Botan::Public_Key::public_key_bits(), Botan::SEQUENCE, and Botan::DER_Encoder::start_cons().

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

   {
   std::vector<uint8_t> output;

   DER_Encoder(output).start_cons(SEQUENCE)
         .encode(algorithm_identifier())
         .encode(public_key_bits(), BIT_STRING)
      .end_cons();

   return output;
   }

Member Data Documentation

m_group

DL_Group Botan::DL_Scheme_PublicKey::m_group

protectedinherited

The DL group

Definition at line 97 of file dl_algo.h.

Referenced by Botan::DL_Scheme_PublicKey::algorithm_identifier(), Botan::DL_Scheme_PublicKey::check_key(), Botan::ElGamal_PrivateKey::check_key(), Botan::DSA_PrivateKey::check_key(), Botan::DL_Scheme_PrivateKey::check_key(), Botan::DH_PrivateKey::DH_PrivateKey(), Botan::DH_PublicKey::DH_PublicKey(), Botan::DL_Scheme_PrivateKey::DL_Scheme_PrivateKey(), Botan::DSA_PrivateKey::DSA_PrivateKey(), DSA_PublicKey(), Botan::ElGamal_PrivateKey::ElGamal_PrivateKey(), Botan::DL_Scheme_PublicKey::estimated_strength(), and Botan::DL_Scheme_PublicKey::key_length().

m_y

BigInt Botan::DL_Scheme_PublicKey::m_y

protectedinherited

The DL public key

Definition at line 92 of file dl_algo.h.

Referenced by Botan::DL_Scheme_PublicKey::check_key(), Botan::DL_Scheme_PrivateKey::check_key(), Botan::DH_PrivateKey::DH_PrivateKey(), Botan::DH_PublicKey::DH_PublicKey(), Botan::DL_Scheme_PublicKey::DL_Scheme_PublicKey(), Botan::DSA_PrivateKey::DSA_PrivateKey(), DSA_PublicKey(), Botan::ElGamal_PrivateKey::ElGamal_PrivateKey(), Botan::DL_Scheme_PublicKey::public_key_bits(), and Botan::DH_PublicKey::public_value().

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

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