Botan 2.17.3
Crypto and TLS for C&
Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
Botan::RSA_PublicKey Class Reference

#include <rsa.h>

Inheritance diagram for Botan::RSA_PublicKey:
Botan::Public_Key Botan::RSA_PrivateKey

Public Member Functions

std::string algo_name () const override
 
AlgorithmIdentifier algorithm_identifier () const override
 
bool check_key (RandomNumberGenerator &rng, bool) const override
 
std::unique_ptr< PK_Ops::Encryptioncreate_encryption_op (RandomNumberGenerator &rng, const std::string &params, const std::string &provider) const override
 
std::unique_ptr< PK_Ops::KEM_Encryptioncreate_kem_encryption_op (RandomNumberGenerator &rng, const std::string &params, const std::string &provider) const override
 
std::unique_ptr< PK_Ops::Verificationcreate_verification_op (const std::string &params, const std::string &provider) const override
 
virtual Signature_Format default_x509_signature_format () const
 
size_t estimated_strength () const override
 
std::string fingerprint_public (const std::string &alg="SHA-256") const
 
const BigIntget_e () const
 
const BigIntget_n () const
 
virtual OID get_oid () const
 
size_t key_length () const override
 
virtual size_t message_part_size () const
 
virtual size_t message_parts () const
 
std::shared_ptr< const RSA_Public_Data > public_data () const
 
std::vector< uint8_t > public_key_bits () const override
 
 RSA_PublicKey (const AlgorithmIdentifier &alg_id, const std::vector< uint8_t > &key_bits)
 
 RSA_PublicKey (const BigInt &n, const BigInt &e)
 
std::vector< uint8_t > subject_public_key () const
 

Protected Member Functions

void init (BigInt &&n, BigInt &&e)
 
 RSA_PublicKey ()=default
 

Protected Attributes

std::shared_ptr< const RSA_Public_Data > m_public
 

Detailed Description

RSA Public Key

Definition at line 25 of file rsa.h.

Constructor & Destructor Documentation

◆ RSA_PublicKey() [1/3]

Botan::RSA_PublicKey::RSA_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 118 of file rsa.cpp.

120 {
121 BigInt n, e;
122 BER_Decoder(key_bits)
123 .start_cons(SEQUENCE)
124 .decode(n)
125 .decode(e)
126 .end_cons();
127
128 init(std::move(n), std::move(e));
129 }
void init(BigInt &&n, BigInt &&e)
Definition: rsa.cpp:111
@ SEQUENCE
Definition: asn1_obj.h:42

References Botan::BER_Decoder::decode(), Botan::BER_Decoder::end_cons(), init(), Botan::SEQUENCE, and Botan::BER_Decoder::start_cons().

◆ RSA_PublicKey() [2/3]

Botan::RSA_PublicKey::RSA_PublicKey ( const BigInt n,
const BigInt e 
)

Create a public key.

  • n the modulus
  • e the exponent

Definition at line 131 of file rsa.cpp.

132 {
133 BigInt n = modulus;
134 BigInt e = exponent;
135 init(std::move(n), std::move(e));
136 }

References init().

◆ RSA_PublicKey() [3/3]

Botan::RSA_PublicKey::RSA_PublicKey ( )
protecteddefault

Member Function Documentation

◆ algo_name()

std::string Botan::RSA_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 43 of file rsa.h.

43{ return "RSA"; }

Referenced by Botan::RSA_PrivateKey::create_decryption_op(), create_encryption_op(), Botan::RSA_PrivateKey::create_kem_decryption_op(), create_kem_encryption_op(), Botan::RSA_PrivateKey::create_signature_op(), create_verification_op(), and Botan::RSA_PrivateKey::RSA_PrivateKey().

◆ algorithm_identifier()

AlgorithmIdentifier Botan::RSA_PublicKey::algorithm_identifier ( ) const
overridevirtual
Returns
X.509 AlgorithmIdentifier for this key

Implements Botan::Public_Key.

Definition at line 148 of file rsa.cpp.

149 {
150 return AlgorithmIdentifier(get_oid(), AlgorithmIdentifier::USE_NULL_PARAM);
151 }
virtual OID get_oid() const
Definition: pk_keys.cpp:53

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

◆ check_key()

bool Botan::RSA_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::RSA_PrivateKey.

Definition at line 168 of file rsa.cpp.

169 {
170 if(get_n() < 35 || get_n().is_even() || get_e() < 3 || get_e().is_even())
171 return false;
172 return true;
173 }
const BigInt & get_n() const
Definition: rsa.cpp:108
const BigInt & get_e() const
Definition: rsa.cpp:109

References get_e(), and get_n().

◆ create_encryption_op()

std::unique_ptr< PK_Ops::Encryption > Botan::RSA_PublicKey::create_encryption_op ( RandomNumberGenerator rng,
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 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 from Botan::Public_Key.

Definition at line 638 of file rsa.cpp.

641 {
642#if defined(BOTAN_HAS_OPENSSL)
643 if(provider == "openssl" || provider.empty())
644 {
645 try
646 {
647 return make_openssl_rsa_enc_op(*this, params);
648 }
649 catch(Exception& e)
650 {
651 /*
652 * If OpenSSL for some reason could not handle this (eg due to OAEP params),
653 * throw if openssl was specifically requested but otherwise just fall back
654 * to the normal version.
655 */
656 if(provider == "openssl")
657 throw Lookup_Error("OpenSSL RSA provider rejected key:" + std::string(e.what()));
658 }
659 }
660#endif
661
662 if(provider == "base" || provider.empty())
663 return std::unique_ptr<PK_Ops::Encryption>(new RSA_Encryption_Operation(*this, params));
664 throw Provider_Not_Found(algo_name(), provider);
665 }
std::string algo_name() const override
Definition: rsa.h:43

References algo_name(), and Botan::Exception::what().

◆ create_kem_encryption_op()

std::unique_ptr< PK_Ops::KEM_Encryption > Botan::RSA_PublicKey::create_kem_encryption_op ( RandomNumberGenerator rng,
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 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 from Botan::Public_Key.

Definition at line 668 of file rsa.cpp.

671 {
672 if(provider == "base" || provider.empty())
673 return std::unique_ptr<PK_Ops::KEM_Encryption>(new RSA_KEM_Encryption_Operation(*this, params));
674 throw Provider_Not_Found(algo_name(), provider);
675 }

References algo_name().

◆ create_verification_op()

std::unique_ptr< PK_Ops::Verification > Botan::RSA_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
paramsadditional parameters
providerthe provider to use

Reimplemented from Botan::Public_Key.

Definition at line 678 of file rsa.cpp.

680 {
681#if defined(BOTAN_HAS_OPENSSL)
682 if(provider == "openssl" || provider.empty())
683 {
684 std::unique_ptr<PK_Ops::Verification> res = make_openssl_rsa_ver_op(*this, params);
685 if(res)
686 return res;
687 }
688#endif
689
690 if(provider == "base" || provider.empty())
691 return std::unique_ptr<PK_Ops::Verification>(new RSA_Verify_Operation(*this, params));
692
693 throw Provider_Not_Found(algo_name(), provider);
694 }

References algo_name().

◆ 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 125 of file pk_keys.h.

126 {
127 return (this->message_parts() >= 2) ? DER_SEQUENCE : IEEE_1363;
128 }
virtual size_t message_parts() const
Definition: pk_keys.h:112
@ DER_SEQUENCE
Definition: pk_keys.h:23
@ IEEE_1363
Definition: pk_keys.h:23

References Botan::DER_SEQUENCE, and Botan::IEEE_1363.

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

◆ estimated_strength()

size_t Botan::RSA_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 143 of file rsa.cpp.

144 {
145 return if_work_factor(key_length());
146 }
size_t key_length() const override
Definition: rsa.cpp:138
size_t if_work_factor(size_t bits)
Definition: workfactor.cpp:38

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

◆ 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 77 of file pk_keys.cpp.

78 {
80 }
std::vector< uint8_t > subject_public_key() const
Definition: pk_keys.cpp:38
std::string create_hex_fingerprint(const uint8_t bits[], size_t bits_len, const std::string &hash_name)
Definition: pk_keys.cpp:17
AlgorithmIdentifier hash_algo
Definition: x509_obj.cpp:22

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

◆ get_e()

const BigInt & Botan::RSA_PublicKey::get_e ( ) const
Returns
public exponent

Definition at line 109 of file rsa.cpp.

109{ return m_public->get_e(); }
std::shared_ptr< const RSA_Public_Data > m_public
Definition: rsa.h:86

References m_public.

Referenced by check_key(), Botan::RSA_PrivateKey::check_key(), Botan::RSA_PrivateKey::private_key_bits(), and public_key_bits().

◆ get_n()

const BigInt & Botan::RSA_PublicKey::get_n ( ) const
Returns
public modulus

Definition at line 108 of file rsa.cpp.

108{ return m_public->get_n(); }

References m_public.

Referenced by check_key(), Botan::RSA_PrivateKey::check_key(), Botan::RSA_PrivateKey::private_key_bits(), and public_key_bits().

◆ get_oid()

OID Botan::Public_Key::get_oid ( ) const
virtualinherited

◆ init()

void Botan::RSA_PublicKey::init ( BigInt &&  n,
BigInt &&  e 
)
protected

Definition at line 111 of file rsa.cpp.

112 {
113 if(n.is_negative() || n.is_even() || e.is_negative() || e.is_even())
114 throw Decoding_Error("Invalid RSA public key parameters");
115 m_public = std::make_shared<RSA_Public_Data>(std::move(n), std::move(e));
116 }

References m_public.

Referenced by Botan::RSA_PrivateKey::RSA_PrivateKey(), and RSA_PublicKey().

◆ key_length()

size_t Botan::RSA_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 138 of file rsa.cpp.

139 {
140 return m_public->public_modulus_bits();
141 }

References m_public.

Referenced by estimated_strength().

◆ 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 123 of file pk_keys.h.

123{ 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 112 of file pk_keys.h.

112{ return 1; }

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

◆ public_data()

std::shared_ptr< const RSA_Public_Data > Botan::RSA_PublicKey::public_data ( ) const

Definition at line 103 of file rsa.cpp.

104 {
105 return m_public;
106 }

References m_public.

◆ public_key_bits()

std::vector< uint8_t > Botan::RSA_PublicKey::public_key_bits ( ) const
overridevirtual
Returns
BER encoded public key bits

Implements Botan::Public_Key.

Definition at line 153 of file rsa.cpp.

154 {
155 std::vector<uint8_t> output;
156 DER_Encoder der(output);
157 der.start_cons(SEQUENCE)
158 .encode(get_n())
159 .encode(get_e())
160 .end_cons();
161
162 return output;
163 }

References Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), get_e(), get_n(), Botan::SEQUENCE, and Botan::DER_Encoder::start_cons().

◆ 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.

39 {
40 std::vector<uint8_t> output;
41
42 DER_Encoder(output).start_cons(SEQUENCE)
43 .encode(algorithm_identifier())
44 .encode(public_key_bits(), BIT_STRING)
45 .end_cons();
46
47 return output;
48 }
virtual AlgorithmIdentifier algorithm_identifier() const =0
virtual std::vector< uint8_t > public_key_bits() const =0
@ BIT_STRING
Definition: asn1_obj.h:37

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().

Member Data Documentation

◆ m_public

std::shared_ptr<const RSA_Public_Data> Botan::RSA_PublicKey::m_public
protected

Definition at line 86 of file rsa.h.

Referenced by get_e(), get_n(), init(), key_length(), and public_data().


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