Botan  1.11.10
Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
Botan::IF_Scheme_PublicKey Class Referenceabstract

#include <if_algo.h>

Inheritance diagram for Botan::IF_Scheme_PublicKey:
Botan::Public_Key Botan::IF_Scheme_PrivateKey Botan::RSA_PublicKey Botan::RW_PublicKey Botan::RSA_PrivateKey Botan::RW_PrivateKey Botan::RSA_PrivateKey Botan::RW_PrivateKey

Public Member Functions

virtual std::string algo_name () const =0
 
AlgorithmIdentifier algorithm_identifier () const
 
bool check_key (RandomNumberGenerator &rng, bool) const
 
size_t estimated_strength () const override
 
const BigIntget_e () const
 
const BigIntget_n () const
 
virtual OID get_oid () const
 
 IF_Scheme_PublicKey (const AlgorithmIdentifier &alg_id, const secure_vector< byte > &key_bits)
 
 IF_Scheme_PublicKey (const BigInt &n, const BigInt &e)
 
size_t max_input_bits () const
 
virtual size_t message_part_size () const
 
virtual size_t message_parts () const
 
std::vector< bytex509_subject_public_key () const
 

Protected Member Functions

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

Protected Attributes

BigInt e
 
BigInt n
 

Detailed Description

This class represents public keys of integer factorization based (IF) public key schemes.

Definition at line 21 of file if_algo.h.

Constructor & Destructor Documentation

Botan::IF_Scheme_PublicKey::IF_Scheme_PublicKey ( const AlgorithmIdentifier alg_id,
const secure_vector< byte > &  key_bits 
)

Definition at line 37 of file if_algo.cpp.

References Botan::BER_Decoder::decode(), e, Botan::BER_Decoder::end_cons(), n, Botan::SEQUENCE, Botan::BER_Decoder::start_cons(), and Botan::BER_Decoder::verify_end().

39  {
40  BER_Decoder(key_bits)
41  .start_cons(SEQUENCE)
42  .decode(n)
43  .decode(e)
44  .verify_end()
45  .end_cons();
46  }
Botan::IF_Scheme_PublicKey::IF_Scheme_PublicKey ( const BigInt n,
const BigInt e 
)
inline

Definition at line 27 of file if_algo.h.

27  :
28  n(n), e(e) {}
Botan::IF_Scheme_PublicKey::IF_Scheme_PublicKey ( )
inlineprotected

Definition at line 51 of file if_algo.h.

51 {}

Member Function Documentation

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

Implements Botan::Public_Key.

Definition at line 21 of file if_algo.cpp.

References Botan::Public_Key::get_oid(), and Botan::AlgorithmIdentifier::USE_NULL_PARAM.

22  {
23  return AlgorithmIdentifier(get_oid(),
25  }
virtual OID get_oid() const
Definition: pk_keys.cpp:17
bool Botan::IF_Scheme_PublicKey::check_key ( RandomNumberGenerator rng,
bool  strong 
) const
virtual

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::IF_Scheme_PrivateKey, Botan::RW_PrivateKey, and Botan::RSA_PrivateKey.

Definition at line 51 of file if_algo.cpp.

References e, Botan::BigInt::is_even(), and n.

52  {
53  if(n < 35 || n.is_even() || e < 2)
54  return false;
55  return true;
56  }
bool is_even() const
Definition: bigint.h:227
size_t Botan::IF_Scheme_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 16 of file if_algo.cpp.

References Botan::BigInt::bits(), Botan::dl_work_factor(), and n.

17  {
18  return dl_work_factor(n.bits());
19  }
size_t bits() const
Definition: bigint.cpp:233
size_t dl_work_factor(size_t bits)
Definition: workfactor.cpp:14
const BigInt& Botan::IF_Scheme_PublicKey::get_e ( ) const
inline
Returns
public exponent

Definition at line 44 of file if_algo.h.

44 { return e; }
const BigInt& Botan::IF_Scheme_PublicKey::get_n ( ) const
inline
Returns
public modulus

Definition at line 39 of file if_algo.h.

39 { return n; }
OID Botan::Public_Key::get_oid ( ) const
virtualinherited

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(), algorithm_identifier(), Botan::GOST_3410_PublicKey::algorithm_identifier(), Botan::EC_PublicKey::algorithm_identifier(), and Botan::McEliece_PublicKey::algorithm_identifier().

18  {
19  try {
20  return OIDS::lookup(algo_name());
21  }
22  catch(Lookup_Error)
23  {
24  throw Lookup_Error("PK algo " + algo_name() + " has no defined OIDs");
25  }
26  }
virtual std::string algo_name() const =0
std::string lookup(const OID &oid)
Definition: oids.cpp:111
void Botan::Public_Key::load_check ( RandomNumberGenerator rng) const
protectedvirtualinherited

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().

32  {
33  if(!check_key(rng, BOTAN_PUBLIC_KEY_STRONG_CHECKS_ON_LOAD))
34  throw Invalid_Argument(algo_name() + ": Invalid public key");
35  }
virtual bool check_key(RandomNumberGenerator &rng, bool strong) const =0
virtual std::string algo_name() const =0
std::invalid_argument Invalid_Argument
Definition: exceptn.h:20
size_t Botan::IF_Scheme_PublicKey::max_input_bits ( ) const
inlinevirtual

Get the maximum message size in bits supported by this public key.

Returns
maximum message size in bits

Implements Botan::Public_Key.

Definition at line 46 of file if_algo.h.

46 { return (n.bits() - 1); }
size_t bits() const
Definition: bigint.cpp:233
virtual size_t Botan::Public_Key::message_part_size ( ) const
inlinevirtualinherited

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

Returns
size of the message parts in bits

Reimplemented in Botan::GOST_3410_PublicKey, Botan::ECDSA_PublicKey, Botan::NR_PublicKey, and Botan::DSA_PublicKey.

Definition at line 67 of file pk_keys.h.

67 { return 0; }
virtual size_t Botan::Public_Key::message_parts ( ) const
inlinevirtualinherited

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

Returns
number of message parts

Reimplemented in Botan::GOST_3410_PublicKey, Botan::ECDSA_PublicKey, Botan::NR_PublicKey, and Botan::DSA_PublicKey.

Definition at line 61 of file pk_keys.h.

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

61 { return 1; }
std::vector< byte > Botan::IF_Scheme_PublicKey::x509_subject_public_key ( ) const
virtual
Returns
X.509 subject key encoding for this key object

Implements Botan::Public_Key.

Definition at line 27 of file if_algo.cpp.

References e, Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), Botan::DER_Encoder::get_contents_unlocked(), n, Botan::SEQUENCE, and Botan::DER_Encoder::start_cons().

28  {
29  return DER_Encoder()
30  .start_cons(SEQUENCE)
31  .encode(n)
32  .encode(e)
33  .end_cons()
34  .get_contents_unlocked();
35  }

Member Data Documentation

BigInt Botan::IF_Scheme_PublicKey::e
protected
BigInt Botan::IF_Scheme_PublicKey::n
protected

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