Botan  2.1.0
Crypto and TLS for C++11
Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
Botan::EC_PublicKey Class Referenceabstract

#include <ecc_key.h>

Inheritance diagram for Botan::EC_PublicKey:
Botan::Public_Key Botan::EC_PrivateKey Botan::ECDH_PublicKey Botan::ECDSA_PublicKey Botan::ECGDSA_PublicKey Botan::ECKCDSA_PublicKey Botan::GOST_3410_PublicKey Botan::ECDH_PrivateKey Botan::ECDSA_PrivateKey Botan::ECGDSA_PrivateKey Botan::ECKCDSA_PrivateKey Botan::GOST_3410_PrivateKey Botan::ECDH_PrivateKey Botan::ECDSA_PrivateKey Botan::ECGDSA_PrivateKey Botan::ECKCDSA_PrivateKey Botan::GOST_3410_PrivateKey

Public Member Functions

virtual std::string algo_name () const =0
 
AlgorithmIdentifier algorithm_identifier () const override
 
bool check_key (RandomNumberGenerator &rng, bool strong) const override
 
virtual std::unique_ptr< PK_Ops::Encryptioncreate_encryption_op (RandomNumberGenerator &rng, const std::string &params, const std::string &provider) const
 
virtual std::unique_ptr< PK_Ops::KEM_Encryptioncreate_kem_encryption_op (RandomNumberGenerator &rng, const std::string &params, const std::string &provider) const
 
virtual std::unique_ptr< PK_Ops::Verificationcreate_verification_op (const std::string &params, const std::string &provider) const
 
std::vector< uint8_t > DER_domain () const
 
const EC_Groupdomain () const
 
EC_Group_Encoding domain_format () const
 
 EC_PublicKey (const EC_Group &dom_par, const PointGFp &pub_point)
 
 EC_PublicKey (const AlgorithmIdentifier &alg_id, const std::vector< uint8_t > &key_bits)
 
 EC_PublicKey (const EC_PublicKey &other)=default
 
size_t estimated_strength () const override
 
virtual OID get_oid () const
 
size_t key_length () const override
 
virtual size_t message_part_size () const
 
virtual size_t message_parts () const
 
EC_PublicKeyoperator= (const EC_PublicKey &other)=default
 
std::vector< uint8_t > public_key_bits () const override
 
const PointGFppublic_point () const
 
void set_parameter_encoding (EC_Group_Encoding enc)
 
std::vector< uint8_t > subject_public_key () const
 
virtual ~EC_PublicKey ()=default
 

Protected Member Functions

 EC_PublicKey ()
 

Protected Attributes

EC_Group_Encoding m_domain_encoding
 
EC_Group m_domain_params
 
PointGFp m_public_key
 

Detailed Description

This class represents abstract ECC public keys. When encoding a key via an encoder that can be accessed via the corresponding member functions, the key will decide upon its internally stored encoding information whether to encode itself with or without domain parameters, or using the domain parameter oid. Furthermore, a public key without domain parameters can be decoded. In that case, it cannot be used for verification until its domain parameters are set by calling the corresponding member function.

Definition at line 29 of file ecc_key.h.

Constructor & Destructor Documentation

Botan::EC_PublicKey::EC_PublicKey ( const EC_Group dom_par,
const PointGFp pub_point 
)

Create a public key.

Parameters
dom_parEC domain parameters
pub_pointpublic point on the curve

Definition at line 31 of file ecc_key.cpp.

References domain(), and public_point().

32  :
33  m_domain_params(dom_par), m_public_key(pub_point),
35  {
36  if(domain().get_curve() != public_point().get_curve())
37  throw Invalid_Argument("EC_PublicKey: curve mismatch in constructor");
38  }
const EC_Group & domain() const
Definition: ecc_key.h:73
PointGFp m_public_key
Definition: ecc_key.h:103
const PointGFp & public_point() const
Definition: ecc_key.h:58
EC_Group m_domain_params
Definition: ecc_key.h:102
EC_Group_Encoding m_domain_encoding
Definition: ecc_key.h:104
Botan::EC_PublicKey::EC_PublicKey ( const AlgorithmIdentifier alg_id,
const std::vector< uint8_t > &  key_bits 
)

Load a public key.

Parameters
alg_idthe X.509 algorithm identifier
key_bitsDER encoded public key bits

Definition at line 40 of file ecc_key.cpp.

References Botan::AlgorithmIdentifier::parameters.

41  :
42  m_domain_params{EC_Group(alg_id.parameters)},
43  m_public_key{OS2ECP(key_bits, domain().get_curve())},
45  {}
const EC_Group & domain() const
Definition: ecc_key.h:73
PointGFp m_public_key
Definition: ecc_key.h:103
PointGFp OS2ECP(const uint8_t data[], size_t data_len, const CurveGFp &curve)
Definition: point_gfp.cpp:544
EC_Group m_domain_params
Definition: ecc_key.h:102
EC_Group_Encoding m_domain_encoding
Definition: ecc_key.h:104
Botan::EC_PublicKey::EC_PublicKey ( const EC_PublicKey other)
default
virtual Botan::EC_PublicKey::~EC_PublicKey ( )
virtualdefault
Botan::EC_PublicKey::EC_PublicKey ( )
inlineprotected

Definition at line 99 of file ecc_key.h.

Member Function Documentation

virtual std::string Botan::Public_Key::algo_name ( ) const
pure virtualinherited
AlgorithmIdentifier Botan::EC_PublicKey::algorithm_identifier ( ) const
overridevirtual
Returns
X.509 AlgorithmIdentifier for this key

Implements Botan::Public_Key.

Reimplemented in Botan::GOST_3410_PublicKey.

Definition at line 81 of file ecc_key.cpp.

References DER_domain(), and Botan::Public_Key::get_oid().

Referenced by Botan::GOST_3410_PrivateKey::pkcs8_algorithm_identifier().

82  {
83  return AlgorithmIdentifier(get_oid(), DER_domain());
84  }
virtual OID get_oid() const
Definition: pk_keys.cpp:30
std::vector< uint8_t > DER_domain() const
Definition: ecc_key.h:85
bool Botan::EC_PublicKey::check_key ( RandomNumberGenerator rng,
bool  strong 
) const
overridevirtual

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, Botan::ECGDSA_PrivateKey, and Botan::ECKCDSA_PrivateKey.

Definition at line 47 of file ecc_key.cpp.

References Botan::EC_Group::get_cofactor(), Botan::EC_Group::get_order(), Botan::CT::is_zero(), Botan::PointGFp::is_zero(), m_domain_params, Botan::PointGFp::on_the_curve(), public_point(), and Botan::EC_Group::verify_group().

49  {
50  //verify domain parameters
52  {
53  return false;
54  }
55  //check that public point is not at infinity
56  if(public_point().is_zero())
57  {
58  return false;
59  }
60  //check that public point is on the curve
61  if(!public_point().on_the_curve())
62  {
63  return false;
64  }
66  {
68  {
69  return false;
70  }
71  //check that public point has order q
73  {
74  return false;
75  }
76  }
77  return true;
78  }
const PointGFp & public_point() const
Definition: ecc_key.h:58
const BigInt & get_order() const
Definition: ec_group.h:101
T is_zero(T x)
Definition: ct_utils.h:110
bool on_the_curve() const
Definition: point_gfp.cpp:414
bool is_zero() const
Definition: point_gfp.h:177
bool verify_group(RandomNumberGenerator &rng, bool strong=false) const
Definition: ec_group.cpp:134
EC_Group m_domain_params
Definition: ecc_key.h:102
const BigInt & get_cofactor() const
Definition: ec_group.h:107
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
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::RSA_PublicKey, and Botan::ElGamal_PublicKey.

Definition at line 79 of file pk_keys.cpp.

References Botan::Public_Key::algo_name().

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

82  {
83  throw Lookup_Error(algo_name() + " does not support encryption");
84  }
virtual std::string algo_name() const =0
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
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::RSA_PublicKey, and Botan::McEliece_PublicKey.

Definition at line 87 of file pk_keys.cpp.

References Botan::Public_Key::algo_name().

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

90  {
91  throw Lookup_Error(algo_name() + " does not support KEM encryption");
92  }
virtual std::string algo_name() const =0
std::unique_ptr< PK_Ops::Verification > Botan::Public_Key::create_verification_op ( 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 verification operation for this key/params or throw

Parameters
paramsadditional parameters
providerthe provider to use

Reimplemented in Botan::XMSS_WOTS_PublicKey, Botan::XMSS_PublicKey, Botan::RSA_PublicKey, Botan::XMSS_WOTS_Addressed_PublicKey, Botan::GOST_3410_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, and Botan::DSA_PublicKey.

Definition at line 95 of file pk_keys.cpp.

References Botan::Public_Key::algo_name().

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

97  {
98  throw Lookup_Error(algo_name() + " does not support verification");
99  }
virtual std::string algo_name() const =0
std::vector<uint8_t> Botan::EC_PublicKey::DER_domain ( ) const
inline

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

Definition at line 85 of file ecc_key.h.

Referenced by algorithm_identifier().

86  { return domain().DER_encode(domain_format()); }
const EC_Group & domain() const
Definition: ecc_key.h:73
std::vector< uint8_t > DER_encode(EC_Group_Encoding form) const
Definition: ec_group.cpp:92
EC_Group_Encoding domain_format() const
Definition: ecc_key.h:92
const EC_Group& Botan::EC_PublicKey::domain ( ) const
inline

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 73 of file ecc_key.h.

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

73 { return m_domain_params; }
EC_Group m_domain_params
Definition: ecc_key.h:102
EC_Group_Encoding Botan::EC_PublicKey::domain_format ( ) const
inline

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

Returns
the encoding to use

Definition at line 92 of file ecc_key.h.

93  { return m_domain_encoding; }
EC_Group_Encoding m_domain_encoding
Definition: ecc_key.h:104
size_t Botan::EC_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::Public_Key.

Definition at line 26 of file ecc_key.cpp.

References Botan::ecp_work_factor(), and key_length().

27  {
28  return ecp_work_factor(key_length());
29  }
size_t ecp_work_factor(size_t bits)
Definition: workfactor.cpp:14
size_t key_length() const override
Definition: ecc_key.cpp:21
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 30 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::McEliece_PublicKey::algorithm_identifier(), Botan::RSA_PublicKey::algorithm_identifier(), Botan::GOST_3410_PublicKey::algorithm_identifier(), algorithm_identifier(), Botan::TPM_PrivateKey::algorithm_identifier(), and Botan::XMSS_WOTS_Addressed_PublicKey::get_oid().

31  {
32  try {
33  return OIDS::lookup(algo_name());
34  }
35  catch(Lookup_Error&)
36  {
37  throw Lookup_Error("PK algo " + algo_name() + " has no defined OIDs");
38  }
39  }
virtual std::string algo_name() const =0
std::string lookup(const OID &oid)
Definition: oids.cpp:18
size_t Botan::EC_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 21 of file ecc_key.cpp.

References Botan::BigInt::bits(), domain(), Botan::EC_Group::get_curve(), and Botan::CurveGFp::get_p().

Referenced by estimated_strength().

22  {
23  return domain().get_curve().get_p().bits();
24  }
const EC_Group & domain() const
Definition: ecc_key.h:73
size_t bits() const
Definition: bigint.cpp:184
const CurveGFp & get_curve() const
Definition: ec_group.h:89
const BigInt & get_p() const
Definition: curve_gfp.h:91
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::GOST_3410_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, and Botan::DSA_PublicKey.

Definition at line 114 of file pk_keys.h.

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

114 { return 0; }
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::GOST_3410_PublicKey, Botan::ECDSA_PublicKey, Botan::ECGDSA_PublicKey, Botan::ECKCDSA_PublicKey, and Botan::DSA_PublicKey.

Definition at line 103 of file pk_keys.h.

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

103 { return 1; }
EC_PublicKey& Botan::EC_PublicKey::operator= ( const EC_PublicKey other)
default
std::vector< uint8_t > Botan::EC_PublicKey::public_key_bits ( ) const
overridevirtual
Returns
BER encoded public key bits

Implements Botan::Public_Key.

Reimplemented in Botan::GOST_3410_PublicKey.

Definition at line 86 of file ecc_key.cpp.

References Botan::PointGFp::COMPRESSED, Botan::EC2OSP(), public_point(), and Botan::unlock().

Referenced by Botan::EC_PrivateKey::EC_PrivateKey().

87  {
89  }
secure_vector< uint8_t > EC2OSP(const PointGFp &point, uint8_t format)
Definition: point_gfp.cpp:470
const PointGFp & public_point() const
Definition: ecc_key.h:58
std::vector< T > unlock(const secure_vector< T > &in)
Definition: secmem.h:125
const PointGFp& Botan::EC_PublicKey::public_point ( ) const
inline

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 58 of file ecc_key.h.

Referenced by check_key(), Botan::ECGDSA_PrivateKey::check_key(), Botan::ECKCDSA_PrivateKey::check_key(), Botan::ECDSA_PrivateKey::check_key(), EC_PublicKey(), Botan::GOST_3410_PublicKey::public_key_bits(), and public_key_bits().

58 { return m_public_key; }
PointGFp m_public_key
Definition: ecc_key.h:103
void Botan::EC_PublicKey::set_parameter_encoding ( EC_Group_Encoding  enc)

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

Parameters
encthe encoding to use

Definition at line 91 of file ecc_key.cpp.

References Botan::EC_DOMPAR_ENC_EXPLICIT, Botan::EC_DOMPAR_ENC_IMPLICITCA, Botan::EC_DOMPAR_ENC_OID, Botan::EC_Group::get_oid(), m_domain_encoding, and m_domain_params.

92  {
93  if(form != EC_DOMPAR_ENC_EXPLICIT &&
94  form != EC_DOMPAR_ENC_IMPLICITCA &&
95  form != EC_DOMPAR_ENC_OID)
96  throw Invalid_Argument("Invalid encoding form for EC-key object specified");
97 
98  if((form == EC_DOMPAR_ENC_OID) && (m_domain_params.get_oid() == ""))
99  throw Invalid_Argument("Invalid encoding form OID specified for "
100  "EC-key object whose corresponding domain "
101  "parameters are without oid");
102 
103  m_domain_encoding = form;
104  }
std::string get_oid() const
Definition: ec_group.h:115
EC_Group m_domain_params
Definition: ecc_key.h:102
EC_Group_Encoding m_domain_encoding
Definition: ecc_key.h:104
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 17 of file pk_keys.cpp.

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

Referenced by Botan::X509::BER_encode(), and Botan::X509::PEM_encode().

18  {
19  return DER_Encoder()
20  .start_cons(SEQUENCE)
21  .encode(algorithm_identifier())
22  .encode(public_key_bits(), BIT_STRING)
23  .end_cons()
24  .get_contents_unlocked();
25  }
virtual std::vector< uint8_t > public_key_bits() const =0
virtual AlgorithmIdentifier algorithm_identifier() const =0

Member Data Documentation

EC_Group_Encoding Botan::EC_PublicKey::m_domain_encoding
protected

Definition at line 104 of file ecc_key.h.

Referenced by Botan::EC_PrivateKey::EC_PrivateKey(), and set_parameter_encoding().

EC_Group Botan::EC_PublicKey::m_domain_params
protected
PointGFp Botan::EC_PublicKey::m_public_key
protected

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