Botan  1.11.15
Public Member Functions | Protected Member Functions | Protected Attributes
Botan::GOST_3410_PublicKey Class Reference

#include <gost_3410.h>

Inheritance diagram for Botan::GOST_3410_PublicKey:
Botan::EC_PublicKey Botan::Public_Key Botan::GOST_3410_PrivateKey

List of all members.

Public Member Functions

std::string algo_name () const
AlgorithmIdentifier algorithm_identifier () const
bool check_key (RandomNumberGenerator &rng, bool strong) const
std::vector< byteDER_domain () const
const EC_Groupdomain () const
EC_Group_Encoding domain_format () const
size_t estimated_strength () const override
virtual OID get_oid () const
 GOST_3410_PublicKey (const EC_Group &dom_par, const PointGFp &public_point)
 GOST_3410_PublicKey (const AlgorithmIdentifier &alg_id, const secure_vector< byte > &key_bits)
size_t max_input_bits () const
size_t message_part_size () const
size_t message_parts () const
const PointGFppublic_point () const
void set_parameter_encoding (EC_Group_Encoding enc)
std::vector< bytex509_subject_public_key () const

Protected Member Functions

 GOST_3410_PublicKey ()
virtual void load_check (RandomNumberGenerator &rng) const

Protected Attributes

EC_Group_Encoding domain_encoding
EC_Group domain_params
PointGFp public_key

Detailed Description

GOST-34.10 Public Key

Definition at line 20 of file gost_3410.h.


Constructor & Destructor Documentation

Botan::GOST_3410_PublicKey::GOST_3410_PublicKey ( const EC_Group dom_par,
const PointGFp public_point 
) [inline]

Construct a public key from a given public point.

Parameters:
dom_parthe domain parameters associated with this key
public_pointthe public point defining this key

Definition at line 29 of file gost_3410.h.

                                                        :
         EC_PublicKey(dom_par, public_point) {}
Botan::GOST_3410_PublicKey::GOST_3410_PublicKey ( const AlgorithmIdentifier alg_id,
const secure_vector< byte > &  key_bits 
)

Construct from X.509 algorithm id and subject public key bits

Definition at line 51 of file gost_3410.cpp.

References BOTAN_ASSERT, Botan::BER_Decoder::decode(), Botan::EC_PublicKey::domain(), Botan::EC_PublicKey::domain_params, Botan::OCTET_STRING, Botan::PointGFp::on_the_curve(), Botan::AlgorithmIdentifier::parameters, Botan::EC_PublicKey::public_key, Botan::SEQUENCE, Botan::BER_Decoder::start_cons(), x, and y.

   {
   OID ecc_param_id;

   // Also includes hash and cipher OIDs... brilliant design guys
   BER_Decoder(alg_id.parameters).start_cons(SEQUENCE).decode(ecc_param_id);

   domain_params = EC_Group(ecc_param_id);

   secure_vector<byte> bits;
   BER_Decoder(key_bits).decode(bits, OCTET_STRING);

   const size_t part_size = bits.size() / 2;

   // Keys are stored in little endian format (WTF)
   for(size_t i = 0; i != part_size / 2; ++i)
      {
      std::swap(bits[i], bits[part_size-1-i]);
      std::swap(bits[part_size+i], bits[2*part_size-1-i]);
      }

   BigInt x(&bits[0], part_size);
   BigInt y(&bits[part_size], part_size);

   public_key = PointGFp(domain().get_curve(), x, y);

   BOTAN_ASSERT(public_key.on_the_curve(),
                "Loaded GOST 34.10 public key is on the curve");
   }

Definition at line 63 of file gost_3410.h.

{}

Member Function Documentation

std::string Botan::GOST_3410_PublicKey::algo_name ( ) const [inline, virtual]

Get this keys algorithm name.

Returns:
this keys algorithm name

Implements Botan::Public_Key.

Definition at line 43 of file gost_3410.h.

{ return "GOST-34.10"; }
Returns:
X.509 AlgorithmIdentifier for this key

Reimplemented from Botan::EC_PublicKey.

Definition at line 40 of file gost_3410.cpp.

References Botan::EC_PublicKey::domain(), Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), Botan::DER_Encoder::get_contents_unlocked(), Botan::Public_Key::get_oid(), Botan::SEQUENCE, and Botan::DER_Encoder::start_cons().

   {
   std::vector<byte> params =
      DER_Encoder().start_cons(SEQUENCE)
         .encode(OID(domain().get_oid()))
         .end_cons()
      .get_contents_unlocked();

   return AlgorithmIdentifier(get_oid(), params);
   }
bool Botan::EC_PublicKey::check_key ( RandomNumberGenerator rng,
bool  strong 
) const [virtual, inherited]

Test the key values for consistency.

Parameters:
rngrng to use
strongwhether to perform strong and lengthy version of the test
Returns:
true if the test is passed

Implements Botan::Public_Key.

Reimplemented in Botan::ECDSA_PrivateKey.

Definition at line 44 of file ecc_key.cpp.

References Botan::PointGFp::on_the_curve(), and Botan::EC_PublicKey::public_point().

   {
   return public_point().on_the_curve();
   }
std::vector<byte> Botan::EC_PublicKey::DER_domain ( ) const [inline, inherited]

Return the DER encoding of this keys domain in whatever format is preset for this particular key

Definition at line 72 of file ecc_key.h.

Referenced by Botan::EC_PublicKey::algorithm_identifier().

         { return domain().DER_encode(domain_format()); }
const EC_Group& Botan::EC_PublicKey::domain ( ) const [inline, inherited]

Get the domain parameters of this key.

Exceptions:
Invalid_Stateis thrown if the domain parameters of this point are not set
Returns:
the domain parameters of this key

Definition at line 60 of file ecc_key.h.

Referenced by algorithm_identifier(), Botan::EC_PrivateKey::EC_PrivateKey(), Botan::EC_PublicKey::EC_PublicKey(), Botan::EC_PublicKey::estimated_strength(), and GOST_3410_PublicKey().

{ return domain_params; }

Get the domain parameter encoding to be used when encoding this key.

Returns:
the encoding to use

Definition at line 79 of file ecc_key.h.

         { return domain_encoding; }
size_t Botan::EC_PublicKey::estimated_strength ( ) const [override, virtual, inherited]

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 21 of file ecc_key.cpp.

References Botan::EC_PublicKey::domain(), and Botan::ecp_work_factor().

   {
   return ecp_work_factor(domain().get_curve().get_p().bits());
   }
OID Botan::Public_Key::get_oid ( ) const [virtual, inherited]

Get the OID of the underlying public key scheme.

Returns:
OID of the public key scheme

Definition at line 17 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::IF_Scheme_PublicKey::algorithm_identifier(), algorithm_identifier(), Botan::EC_PublicKey::algorithm_identifier(), and Botan::McEliece_PublicKey::algorithm_identifier().

   {
   try {
      return OIDS::lookup(algo_name());
      }
   catch(Lookup_Error)
      {
      throw Lookup_Error("PK algo " + algo_name() + " has no defined OIDs");
      }
   }
void Botan::Public_Key::load_check ( RandomNumberGenerator rng) const [protected, virtual, inherited]

Self-test after loading a key

Parameters:
rnga random number generator

Reimplemented in Botan::Private_Key.

Definition at line 31 of file pk_keys.cpp.

References Botan::Public_Key::algo_name(), and Botan::Public_Key::check_key().

   {
   if(!check_key(rng, BOTAN_PUBLIC_KEY_STRONG_CHECKS_ON_LOAD))
      throw Invalid_Argument(algo_name() + ": Invalid public key");
   }
size_t Botan::GOST_3410_PublicKey::max_input_bits ( ) const [inline, virtual]

Get the maximum number of bits allowed to be fed to this key. This is the bitlength of the order of the base point.

Returns:
the maximum number of input bits

Implements Botan::Public_Key.

Definition at line 55 of file gost_3410.h.

{ return domain().get_order().bits(); }
size_t Botan::GOST_3410_PublicKey::message_part_size ( ) const [inline, virtual]

Find out the message part size supported by this scheme/key.

Returns:
size of the message parts in bits

Reimplemented from Botan::Public_Key.

Definition at line 59 of file gost_3410.h.

         { return domain().get_order().bytes(); }
size_t Botan::GOST_3410_PublicKey::message_parts ( ) const [inline, virtual]

Find out the number of message parts supported by this scheme.

Returns:
number of message parts

Reimplemented from Botan::Public_Key.

Definition at line 57 of file gost_3410.h.

{ return 2; }
const PointGFp& Botan::EC_PublicKey::public_point ( ) const [inline, inherited]

Get the public point of this key.

Exceptions:
Invalid_Stateis thrown if the domain parameters of this point are not set
Returns:
the public point of this key

Definition at line 45 of file ecc_key.h.

Referenced by Botan::EC_PublicKey::check_key(), Botan::ECDSA_PrivateKey::check_key(), Botan::EC_PublicKey::EC_PublicKey(), x509_subject_public_key(), and Botan::EC_PublicKey::x509_subject_public_key().

{ return public_key; }

Set the domain parameter encoding to be used when encoding this key.

Parameters:
encthe encoding to use

Definition at line 60 of file ecc_key.cpp.

References Botan::EC_PublicKey::domain_encoding, Botan::EC_PublicKey::domain_params, Botan::EC_DOMPAR_ENC_EXPLICIT, Botan::EC_DOMPAR_ENC_IMPLICITCA, Botan::EC_DOMPAR_ENC_OID, and Botan::EC_Group::get_oid().

Referenced by Botan::DE_EAC::create_cvc_req(), Botan::DE_EAC::link_cvca(), and Botan::DE_EAC::sign_request().

   {
   if(form != EC_DOMPAR_ENC_EXPLICIT &&
      form != EC_DOMPAR_ENC_IMPLICITCA &&
      form != EC_DOMPAR_ENC_OID)
      throw Invalid_Argument("Invalid encoding form for EC-key object specified");

   if((form == EC_DOMPAR_ENC_OID) && (domain_params.get_oid() == ""))
      throw Invalid_Argument("Invalid encoding form OID specified for "
                             "EC-key object whose corresponding domain "
                             "parameters are without oid");

   domain_encoding = form;
   }
std::vector< byte > Botan::GOST_3410_PublicKey::x509_subject_public_key ( ) const [virtual]
Returns:
X.509 subject key encoding for this key object

Reimplemented from Botan::EC_PublicKey.

Definition at line 17 of file gost_3410.cpp.

References Botan::BigInt::binary_encode(), Botan::BigInt::bytes(), Botan::DER_Encoder::encode(), Botan::PointGFp::get_affine_x(), Botan::PointGFp::get_affine_y(), Botan::DER_Encoder::get_contents_unlocked(), Botan::OCTET_STRING, Botan::EC_PublicKey::public_point(), x, and y.

   {
   // Trust CryptoPro to come up with something obnoxious
   const BigInt x = public_point().get_affine_x();
   const BigInt y = public_point().get_affine_y();

   size_t part_size = std::max(x.bytes(), y.bytes());

   std::vector<byte> bits(2*part_size);

   x.binary_encode(&bits[part_size - x.bytes()]);
   y.binary_encode(&bits[2*part_size - y.bytes()]);

   // Keys are stored in little endian format (WTF)
   for(size_t i = 0; i != part_size / 2; ++i)
      {
      std::swap(bits[i], bits[part_size-1-i]);
      std::swap(bits[part_size+i], bits[2*part_size-1-i]);
      }

   return DER_Encoder().encode(bits, OCTET_STRING).get_contents_unlocked();
   }

Member Data Documentation

PointGFp Botan::EC_PublicKey::public_key [protected, inherited]

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