Botan::RSA_PrivateKey Class Reference

#include <rsa.h>

Inheritance diagram for Botan::RSA_PrivateKey:

Public Member Functions
virtual Signature_Format	_default_x509_signature_format () const
virtual std::optional< size_t >	_signature_element_size_for_DER_encoding () const
std::string	algo_name () const override
AlgorithmIdentifier	algorithm_identifier () const override
bool	check_key (RandomNumberGenerator &rng, bool strong) const override
std::unique_ptr< PK_Ops::Decryption >	create_decryption_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const override
std::unique_ptr< PK_Ops::Encryption >	create_encryption_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const override
std::unique_ptr< PK_Ops::KEM_Decryption >	create_kem_decryption_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const override
std::unique_ptr< PK_Ops::KEM_Encryption >	create_kem_encryption_op (std::string_view params, std::string_view provider) const override
virtual std::unique_ptr< PK_Ops::Key_Agreement >	create_key_agreement_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const
std::unique_ptr< PK_Ops::Signature >	create_signature_op (RandomNumberGenerator &rng, std::string_view params, std::string_view provider) const override
std::unique_ptr< PK_Ops::Verification >	create_verification_op (std::string_view params, std::string_view provider) const override
std::unique_ptr< PK_Ops::Verification >	create_x509_verification_op (const AlgorithmIdentifier &alg_id, std::string_view provider) const override
Signature_Format	default_x509_signature_format () const
size_t	estimated_strength () const override
std::string	fingerprint_private (std::string_view alg) const
std::string	fingerprint_public (std::string_view alg="SHA-256") const
std::unique_ptr< Private_Key >	generate_another (RandomNumberGenerator &rng) const override
const BigInt &	get_c () const
const BigInt &	get_d () const
const BigInt &	get_d1 () const
const BigInt &	get_d2 () const
const BigInt &	get_e () const
const BigInt &	get_int_field (std::string_view field) const override
const BigInt &	get_n () const
OID	get_oid () const
const BigInt &	get_p () const
const BigInt &	get_q () const
size_t	key_length () const override
size_t	message_part_size () const
size_t	message_parts () const
virtual OID	object_identifier () const
virtual AlgorithmIdentifier	pkcs8_algorithm_identifier () const
std::shared_ptr< const RSA_Private_Data >	private_data () const
secure_vector< uint8_t >	private_key_bits () const override
secure_vector< uint8_t >	private_key_info () const
std::shared_ptr< const RSA_Public_Data >	public_data () const
std::unique_ptr< Public_Key >	public_key () const override
std::vector< uint8_t >	public_key_bits () const override
virtual secure_vector< uint8_t >	raw_private_key_bits () const
std::vector< uint8_t >	raw_public_key_bits () const override
virtual std::optional< uint64_t >	remaining_operations () const
	Retrieves the number of remaining operations if this is a stateful private key.
	RSA_PrivateKey (const AlgorithmIdentifier &alg_id, std::span< const uint8_t > key_bits)
	RSA_PrivateKey (const BigInt &p, const BigInt &q, const BigInt &e, const BigInt &d=BigInt::zero(), const BigInt &n=BigInt::zero())
	RSA_PrivateKey (RandomNumberGenerator &rng, size_t bits, size_t exp=65537)
virtual bool	stateful_operation () const
std::vector< uint8_t >	subject_public_key () const
bool	supports_operation (PublicKeyOperation op) const override

Protected Member Functions
void	init (BigInt &&n, BigInt &&e)

Protected Attributes
std::shared_ptr< const RSA_Public_Data >	m_public

Detailed Description

RSA Private Key

Definition at line 101 of file rsa.h.

Constructor & Destructor Documentation

RSA_PrivateKey() [1/3]

Botan::RSA_PrivateKey::RSA_PrivateKey	(	const AlgorithmIdentifier &	alg_id,
		std::span< const uint8_t >	key_bits )

Load a private key.

Parameters

alg_id	the X.509 algorithm identifier
key_bits	PKCS#1 RSAPrivateKey bits

Definition at line 282 of file rsa.cpp.

                                                                                                 {
   if(alg_id.oid().registered_name() == "RSA" && !alg_id.parameters_are_null_or_empty()) {
      throw Decoding_Error("Unexpected parameters for RSA private key");
   }
 
   BigInt n;
   BigInt e;
   BigInt d;
   BigInt p;
   BigInt q;
   BigInt d1;
   BigInt d2;
   BigInt c;
 
   BER_Decoder(key_bits, BER_Decoder::Limits::DER())
      .start_sequence()
      .decode_and_check<size_t>(0, "Unknown PKCS #1 key format version")
      .decode(n)
      .decode(e)
      .decode(d)
      .decode(p)
      .decode(q)
      .decode(d1)
      .decode(d2)
      .decode(c)
      .end_cons()
      .verify_end();
 
   RSA_PublicKey::init(std::move(n), std::move(e));
 
   RSA_PrivateKey::init(std::move(d), std::move(p), std::move(q), std::move(d1), std::move(d2), std::move(c));
}

References Botan::BER_Decoder::decode_and_check(), Botan::BER_Decoder::Limits::DER(), Botan::RSA_PublicKey::init(), Botan::AlgorithmIdentifier::oid(), Botan::AlgorithmIdentifier::parameters_are_null_or_empty(), Botan::OID::registered_name(), and Botan::BER_Decoder::start_sequence().

RSA_PrivateKey() [2/3]

Botan::RSA_PrivateKey::RSA_PrivateKey	(	const BigInt &	p,
		const BigInt &	q,
		const BigInt &	e,
		const BigInt &	d = BigInt::zero(),
		const BigInt &	n = BigInt::zero() )

Construct a private key from the specified parameters.

Parameters

p	the first prime
q	the second prime
e	the exponent
d	if specified, this has to be d with exp * d = 1 mod (p - 1, q - 1). Leave it as 0 if you wish to the constructor to calculate it.
n	if specified, this must be n = p * q. Leave it as 0 if you wish to the constructor to calculate it.

Definition at line 315 of file rsa.cpp.

                                                                                                          {
   BigInt p = prime1;
   BigInt q = prime2;
   BigInt n = mod;
   if(n.is_zero()) {
      n = p * q;
   }
 
   BigInt e = exp;
 
   BigInt d = d_exp;
 
   const BigInt p_minus_1 = p - 1;
   const BigInt q_minus_1 = q - 1;
 
   if(d.is_zero()) {
      const BigInt phi_n = lcm(p_minus_1, q_minus_1);
      d = compute_rsa_secret_exponent(e, phi_n, p, q);
   }
 
   BigInt d1 = ct_modulo(d, p_minus_1);
   BigInt d2 = ct_modulo(d, q_minus_1);
   BigInt c = inverse_mod_secret_prime(ct_modulo(q, p), p);
 
   RSA_PublicKey::init(std::move(n), std::move(e));
 
   RSA_PrivateKey::init(std::move(d), std::move(p), std::move(q), std::move(d1), std::move(d2), std::move(c));
}

References Botan::compute_rsa_secret_exponent(), Botan::ct_modulo(), Botan::RSA_PublicKey::init(), Botan::inverse_mod_secret_prime(), Botan::BigInt::is_zero(), and Botan::lcm().

RSA_PrivateKey() [3/3]

Botan::RSA_PrivateKey::RSA_PrivateKey	(	RandomNumberGenerator &	rng,
		size_t	bits,
		size_t	exp = 65537 )

Create a new private key with the specified bit length

Parameters

Random Number Generators	the random number generator to use
bits	the desired bit length of the private key
exp	the public exponent to be used

Definition at line 348 of file rsa.cpp.

                                                                                  {
   constexpr size_t MIN_RSA_BITS = 1024;
   constexpr size_t MAX_RSA_BITS = 16384;
   constexpr size_t MOD_RSA_BITS = 8;
 
   if(bits < MIN_RSA_BITS) {
      throw Invalid_Argument(fmt("Cannot create an RSA key of {} bits: must be at least {} bits", bits, MIN_RSA_BITS));
   } else if(bits > MAX_RSA_BITS) {
      throw Invalid_Argument(
         fmt("Cannot create an RSA key of {} bits: must be no more than {} bits", bits, MAX_RSA_BITS));
   } else if(bits % MOD_RSA_BITS != 0) {
      throw Invalid_Argument(
         fmt("Cannot create an RSA key of {} bits: must be a multiple of {} bits", bits, MOD_RSA_BITS));
   }
 
   if(exp < 3 || exp % 2 == 0) {
      throw Invalid_Argument("Invalid RSA encryption exponent");
   }
 
   const size_t p_bits = (bits + 1) / 2;
   const size_t q_bits = bits - p_bits;
 
   BigInt p;
   BigInt q;
   BigInt n;
   BigInt e = BigInt::from_u64(exp);
 
   for(size_t attempt = 0;; ++attempt) {
      if(attempt > 10) {
         throw Internal_Error("RNG failure during RSA key generation");
      }
 
      // TODO could generate primes in thread pool
      p = generate_rsa_prime(rng, rng, p_bits, e);
      q = generate_rsa_prime(rng, rng, q_bits, e);
 
      const BigInt diff = p - q;
      if(diff.bits() < (bits / 2) - 100) {
         continue;
      }
 
      n = p * q;
 
      if(n.bits() != bits) {
         continue;
      }
 
      break;
   }
 
   const BigInt p_minus_1 = p - 1;
   const BigInt q_minus_1 = q - 1;
 
   const BigInt phi_n = lcm(p_minus_1, q_minus_1);
   // This is guaranteed because p,q == 3 mod 4
   BOTAN_DEBUG_ASSERT(low_zero_bits(phi_n) == 1);
 
   BigInt d = compute_rsa_secret_exponent(e, phi_n, p, q);
   BigInt d1 = ct_modulo(d, p_minus_1);
   BigInt d2 = ct_modulo(d, q_minus_1);
   BigInt c = inverse_mod_secret_prime(ct_modulo(q, p), p);
 
   RSA_PublicKey::init(std::move(n), std::move(e));
 
   RSA_PrivateKey::init(std::move(d), std::move(p), std::move(q), std::move(d1), std::move(d2), std::move(c));
}

References Botan::BigInt::bits(), BOTAN_DEBUG_ASSERT, Botan::compute_rsa_secret_exponent(), Botan::ct_modulo(), Botan::fmt(), Botan::BigInt::from_u64(), Botan::generate_rsa_prime(), Botan::RSA_PublicKey::init(), Botan::inverse_mod_secret_prime(), Botan::lcm(), and Botan::low_zero_bits().

Member Function Documentation

_default_x509_signature_format()

Signature_Format Botan::Asymmetric_Key::_default_x509_signature_format ( ) const

virtualinherited

Reimplemented in Botan::GOST_3410_PublicKey.

Definition at line 30 of file pk_keys.cpp.

                                                                      {
   if(_signature_element_size_for_DER_encoding()) {
      return Signature_Format::DerSequence;
   } else {
      return Signature_Format::Standard;
   }
}

References _signature_element_size_for_DER_encoding(), Botan::DerSequence, and Botan::Standard.

Referenced by Botan::X509_Object::choose_sig_format(), Botan::Public_Key::default_x509_signature_format(), and Botan::PK_Verifier::PK_Verifier().

_signature_element_size_for_DER_encoding()

virtual std::optional< size_t > Botan::Asymmetric_Key::_signature_element_size_for_DER_encoding ( ) const

inlinevirtualinherited

Certain signatures schemes such as ECDSA have more than one element, and certain unfortunate protocols decided the thing to do was not concatenate them as normally done, but instead DER encode each of the elements as independent values.

If this returns a value x then the signature is checked to be exactly 2*x bytes and split in half for DER encoding.

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 144 of file pk_keys.h.

{ return {}; }

Referenced by _default_x509_signature_format(), Botan::Public_Key::message_part_size(), Botan::Public_Key::message_parts(), Botan::PK_Verifier::PK_Verifier(), and Botan::PK_Verifier::PK_Verifier().

algo_name()

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

inlineoverridevirtualinherited

Get the name of the underlying public key scheme.

Returns

name of the public key scheme

Implements Botan::Asymmetric_Key.

Definition at line 41 of file rsa.h.

{ 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 create_x509_verification_op().

algorithm_identifier()

AlgorithmIdentifier Botan::RSA_PublicKey::algorithm_identifier ( ) const

overridevirtualinherited

Return the X.509 AlgorithmIdentifier for this key

Implements Botan::Public_Key.

Definition at line 201 of file rsa.cpp.

                                                              {
   return AlgorithmIdentifier(object_identifier(), AlgorithmIdentifier::USE_NULL_PARAM);
}

References Botan::Asymmetric_Key::object_identifier(), and Botan::AlgorithmIdentifier::USE_NULL_PARAM.

Referenced by Botan::TPM2::RSA_PrivateKey::public_key().

check_key()

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

overridevirtual

Test the key values for consistency.

Note this function is always "best effort"; for many algorithms it is not computationally possible to ensure the key is correctly formed in all respects. There is always the possibility a malformed key will be accepted; this is especially the case for public keys.

Parameters

Random Number Generators	rng to use for randomized testing (may be ignored)
strong	whether to perform strong and lengthy version of the test, however for many algorithms this has no effect

Returns

true if the tests passed

Implements Botan::Asymmetric_Key.

Definition at line 440 of file rsa.cpp.

                                                                            {
   if(get_n() < 35 || get_n().is_even() || get_e() < 3 || get_e().is_even()) {
      return false;
   }
 
   if(get_d() < 2 || get_p() < 3 || get_q() < 3) {
      return false;
   }
 
   if(get_p() * get_q() != get_n()) {
      return false;
   }
 
   if(get_p() == get_q()) {
      return false;
   }
 
   if(get_d1() != ct_modulo(get_d(), get_p() - 1)) {
      return false;
   }
   if(get_d2() != ct_modulo(get_d(), get_q() - 1)) {
      return false;
   }
   if(get_c() != inverse_mod_secret_prime(ct_modulo(get_q(), get_p()), get_p())) {
      return false;
   }
 
   const size_t prob = (strong) ? 128 : 12;
 
   if(!is_prime(get_p(), rng, prob)) {
      return false;
   }
   if(!is_prime(get_q(), rng, prob)) {
      return false;
   }
 
   if(strong) {
      if(ct_modulo(get_e() * get_d(), lcm(get_p() - 1, get_q() - 1)) != 1) {
         return false;
      }
 
#if defined(BOTAN_HAS_PSS) && defined(BOTAN_HAS_SHA_256)
      const std::string padding = "PSS(SHA-256)";
#else
      const std::string padding = "Raw";
#endif
 
      return KeyPair::signature_consistency_check(rng, *this, padding);
   }
 
   return true;
}

References Botan::ct_modulo(), get_c(), get_d(), get_d1(), get_d2(), Botan::RSA_PublicKey::get_e(), Botan::RSA_PublicKey::get_n(), get_p(), get_q(), Botan::inverse_mod_secret_prime(), Botan::is_prime(), Botan::lcm(), and Botan::KeyPair::signature_consistency_check().

create_decryption_op()

std::unique_ptr< PK_Ops::Decryption > Botan::RSA_PrivateKey::create_decryption_op ( RandomNumberGenerator & rng, std::string_view params, std::string_view provider ) const

overridevirtual

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return an decryption operation for this key/params or throw

Parameters

Random Number Generators	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 from Botan::Private_Key.

Definition at line 944 of file rsa.cpp.

                                                                                                        {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_Decryption_Operation>(*this, params, rng);
   }
 
   throw Provider_Not_Found(algo_name(), provider);
}

References Botan::RSA_PublicKey::algo_name().

create_encryption_op()

std::unique_ptr< PK_Ops::Encryption > Botan::RSA_PublicKey::create_encryption_op ( RandomNumberGenerator & rng, std::string_view params, std::string_view provider ) const

overridevirtualinherited

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

Random Number Generators	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 from Botan::Public_Key.

Reimplemented in Botan::TPM2::RSA_PublicKey.

Definition at line 848 of file rsa.cpp.

                                                                                                       {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_Encryption_Operation>(*this, params);
   }
   throw Provider_Not_Found(algo_name(), provider);
}

References algo_name().

create_kem_decryption_op()

std::unique_ptr< PK_Ops::KEM_Decryption > Botan::RSA_PrivateKey::create_kem_decryption_op ( RandomNumberGenerator & rng, std::string_view params, std::string_view provider ) const

overridevirtual

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return a KEM decryption operation for this key/params or throw

Parameters

Random Number Generators	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 from Botan::Private_Key.

Definition at line 954 of file rsa.cpp.

                                                                                                                {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_KEM_Decryption_Operation>(*this, params, rng);
   }
 
   throw Provider_Not_Found(algo_name(), provider);
}

References Botan::RSA_PublicKey::algo_name().

create_kem_encryption_op()

std::unique_ptr< PK_Ops::KEM_Encryption > Botan::RSA_PublicKey::create_kem_encryption_op ( std::string_view params, std::string_view provider ) const

overridevirtualinherited

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

params	additional parameters
provider	the provider to use

Reimplemented from Botan::Public_Key.

Definition at line 857 of file rsa.cpp.

                                                                                                               {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_KEM_Encryption_Operation>(*this, params);
   }
   throw Provider_Not_Found(algo_name(), provider);
}

References algo_name().

create_key_agreement_op()

std::unique_ptr< PK_Ops::Key_Agreement > Botan::Private_Key::create_key_agreement_op ( RandomNumberGenerator & rng, std::string_view params, std::string_view provider ) const

virtualinherited

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return a key agreement operation for this key/params or throw

Parameters

Random Number Generators	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::DH_PrivateKey, Botan::ECDH_PrivateKey, Botan::X25519_PrivateKey, and Botan::X448_PrivateKey.

Definition at line 144 of file pk_keys.cpp.

                                                                                                    {
   throw Lookup_Error(fmt("{} does not support key agreement", algo_name()));
}

References Botan::Asymmetric_Key::algo_name(), and Botan::fmt().

Referenced by Botan::PK_Key_Agreement::PK_Key_Agreement().

create_signature_op()

std::unique_ptr< PK_Ops::Signature > Botan::RSA_PrivateKey::create_signature_op ( RandomNumberGenerator & rng, std::string_view params, std::string_view provider ) const

overridevirtual

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return a signature operation for this key/params or throw

Parameters

Random Number Generators	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 from Botan::Private_Key.

Definition at line 964 of file rsa.cpp.

                                                                                                      {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_Signature_Operation>(*this, params, rng);
   }
 
   throw Provider_Not_Found(algo_name(), provider);
}

References Botan::RSA_PublicKey::algo_name().

create_verification_op()

std::unique_ptr< PK_Ops::Verification > Botan::RSA_PublicKey::create_verification_op ( std::string_view params, std::string_view provider ) const

overridevirtualinherited

This is an internal library function exposed on key types. In 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.

Reimplemented in Botan::TPM2::RSA_PublicKey.

Definition at line 865 of file rsa.cpp.

                                                                                                           {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_Verify_Operation>(*this, params);
   }
 
   throw Provider_Not_Found(algo_name(), provider);
}

References algo_name().

create_x509_verification_op()

std::unique_ptr< PK_Ops::Verification > Botan::RSA_PublicKey::create_x509_verification_op ( const AlgorithmIdentifier & signature_algorithm, std::string_view provider ) const

overridevirtualinherited

This is an internal library function exposed on key types. In all cases applications should use wrappers in pubkey.h

Return a verification operation for this combination of key and signature algorithm or throw.

Parameters

signature_algorithm	is the X.509 algorithm identifier encoding the padding scheme and hash hash function used in the signature if applicable.
provider	the provider to use

Reimplemented from Botan::Public_Key.

Definition at line 935 of file rsa.cpp.

                                                                                                                {
   if(provider == "base" || provider.empty()) {
      return std::make_unique<RSA_Verify_Operation>(*this, parse_rsa_signature_algorithm(alg_id));
   }
 
   throw Provider_Not_Found(algo_name(), provider);
}

References algo_name().

default_x509_signature_format()

Signature_Format Botan::Public_Key::default_x509_signature_format ( ) const

inlineinherited

Definition at line 241 of file pk_keys.h.

                                                                                                           {
         return _default_x509_signature_format();
      }

References Botan::Asymmetric_Key::_default_x509_signature_format(), and default_x509_signature_format().

Referenced by default_x509_signature_format().

estimated_strength()

size_t Botan::RSA_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::Asymmetric_Key.

Definition at line 197 of file rsa.cpp.

                                               {
   return if_work_factor(key_length());
}

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

fingerprint_private()

std::string Botan::Private_Key::fingerprint_private ( std::string_view alg ) const

inherited

Returns

Hash of the PKCS #8 encoding for this key object

Definition at line 101 of file pk_keys.cpp.

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

References Botan::create_hex_fingerprint(), and private_key_bits().

Referenced by Botan::Certificate_Store_In_SQL::find_certs_for_key(), Botan::Certificate_Store_In_SQL::insert_key(), and Botan::Certificate_Store_In_SQL::remove_key().

fingerprint_public()

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

inherited

Returns

Hash of the subject public key

Definition at line 94 of file pk_keys.cpp.

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

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

Referenced by public_key_bits().

generate_another()

std::unique_ptr< Private_Key > Botan::RSA_PublicKey::generate_another ( RandomNumberGenerator & rng ) const

overridevirtualinherited

Generate another (cryptographically independent) key pair using the same algorithm parameters as this key. This is most useful for algorithms that support PublicKeyOperation::KeyAgreement to generate a fitting ephemeral key pair. For other key types it might throw Not_Implemented.

Implements Botan::Asymmetric_Key.

Reimplemented in Botan::TPM2::RSA_PublicKey.

Definition at line 144 of file rsa.cpp.

                                                                                           {
   return std::make_unique<RSA_PrivateKey>(rng, m_public->public_modulus_bits(), 65537);
}

References m_public.

get_c()

const BigInt & Botan::RSA_PrivateKey::get_c

(

)

const

Definition at line 259 of file rsa.cpp.

                                          {
   return m_private->get_c();
}

Referenced by check_key(), and private_key_bits().

get_d()

const BigInt & Botan::RSA_PrivateKey::get_d

(

)

const

Get d with exp * d = 1 mod (p - 1, q - 1).

Returns

d

Definition at line 255 of file rsa.cpp.

                                          {
   return m_private->get_d();
}

Referenced by check_key(), and private_key_bits().

get_d1()

const BigInt & Botan::RSA_PrivateKey::get_d1

(

)

const

Definition at line 263 of file rsa.cpp.

                                           {
   return m_private->get_d1();
}

Referenced by check_key(), and private_key_bits().

get_d2()

const BigInt & Botan::RSA_PrivateKey::get_d2

(

)

const

Definition at line 267 of file rsa.cpp.

                                           {
   return m_private->get_d2();
}

Referenced by check_key(), and private_key_bits().

get_e()

const BigInt & Botan::RSA_PublicKey::get_e ( ) const

inherited

Returns

public exponent

Definition at line 152 of file rsa.cpp.

                                         {
   return m_public->get_e();
}

References m_public.

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

get_int_field()

const BigInt & Botan::RSA_PrivateKey::get_int_field ( std::string_view field ) const

overridevirtual

Access an algorithm specific field

If the field is not known for this algorithm, an Invalid_Argument is thrown. The interpretation of the result requires knowledge of which algorithm is involved. For instance for RSA "p" represents one of the secret primes, while for DSA "p" is the public prime.

Some algorithms may not implement this method at all.

This is primarily used to implement the FFI botan_pubkey_get_field and botan_privkey_get_field functions.

TODO(Botan4) Change this to return by value

Reimplemented from Botan::Asymmetric_Key.

Definition at line 415 of file rsa.cpp.

                                                                      {
   if(field == "p") {
      return m_private->get_p();
   } else if(field == "q") {
      return m_private->get_q();
   } else if(field == "d") {
      return m_private->get_d();
   } else if(field == "c") {
      return m_private->get_c();
   } else if(field == "d1") {
      return m_private->get_d1();
   } else if(field == "d2") {
      return m_private->get_d2();
   } else {
      return RSA_PublicKey::get_int_field(field);
   }
}

References Botan::RSA_PublicKey::get_int_field().

get_n()

const BigInt & Botan::RSA_PublicKey::get_n ( ) const

inherited

Returns

public modulus

Definition at line 148 of file rsa.cpp.

                                         {
   return m_public->get_n();
}

References m_public.

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

get_oid()

OID Botan::Public_Key::get_oid ( ) const

inlineinherited

Deprecated version of object_identifier

Definition at line 168 of file pk_keys.h.

{ return this->object_identifier(); }

References get_oid(), and Botan::Asymmetric_Key::object_identifier().

Referenced by get_oid().

get_p()

const BigInt & Botan::RSA_PrivateKey::get_p

(

)

const

Get the first prime p.

Returns

prime p

Definition at line 247 of file rsa.cpp.

                                          {
   return m_private->get_p();
}

Referenced by check_key(), and private_key_bits().

get_q()

const BigInt & Botan::RSA_PrivateKey::get_q

(

)

const

Get the second prime q.

Returns

prime q

Definition at line 251 of file rsa.cpp.

                                          {
   return m_private->get_q();
}

Referenced by check_key(), and private_key_bits().

init()

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

protectedinherited

Definition at line 156 of file rsa.cpp.

                                               {
   if(n.signum() <= 0 || n.is_even() || n.bits() < 384 || n.bits() > 16384) {
      throw Decoding_Error("Invalid RSA public key modulus");
   }
   if(e.is_even() || e <= 1 || e >= n || e.bits() > 256) {
      throw Decoding_Error("Invalid RSA public key exponent");
   }
   m_public = std::make_shared<RSA_Public_Data>(std::move(n), std::move(e));
}

References m_public.

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

key_length()

size_t Botan::RSA_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 193 of file rsa.cpp.

                                       {
   return m_public->public_modulus_bits();
}

References m_public.

Referenced by estimated_strength().

message_part_size()

size_t Botan::Public_Key::message_part_size ( ) const

inlineinherited

Returns how large each of the message parts referred 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

Definition at line 232 of file pk_keys.h.

                                                                                     {
         return _signature_element_size_for_DER_encoding().value_or(0);
      }

References Botan::Asymmetric_Key::_signature_element_size_for_DER_encoding(), and message_part_size().

Referenced by message_part_size().

message_parts()

size_t Botan::Public_Key::message_parts ( ) const

inlineinherited

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

Definition at line 219 of file pk_keys.h.

                                                                                 {
         return _signature_element_size_for_DER_encoding() ? 2 : 1;
      }

References Botan::Asymmetric_Key::_signature_element_size_for_DER_encoding(), and message_parts().

Referenced by message_parts().

object_identifier()

OID Botan::Asymmetric_Key::object_identifier ( ) const

virtualinherited

Get the OID of the underlying public key scheme.

Returns

OID of the public key scheme

Reimplemented in Botan::Classic_McEliece_PublicKey, Botan::Dilithium_PublicKey, Botan::FrodoKEM_PublicKey, Botan::HSS_LMS_PublicKey, Botan::Kyber_PublicKey, and Botan::SphincsPlus_PublicKey.

Definition at line 22 of file pk_keys.cpp.

                                            {
   try {
      return OID::from_string(algo_name());
   } catch(Lookup_Error&) {
      throw Lookup_Error(fmt("Public key algorithm {} has no defined OIDs", algo_name()));
   }
}

References algo_name(), Botan::fmt(), and Botan::OID::from_string().

Referenced by Botan::DH_PublicKey::algorithm_identifier(), Botan::DSA_PublicKey::algorithm_identifier(), Botan::EC_PublicKey::algorithm_identifier(), Botan::Ed25519_PublicKey::algorithm_identifier(), Botan::Ed448_PublicKey::algorithm_identifier(), Botan::ElGamal_PublicKey::algorithm_identifier(), Botan::GOST_3410_PublicKey::algorithm_identifier(), Botan::McEliece_PublicKey::algorithm_identifier(), Botan::RSA_PublicKey::algorithm_identifier(), Botan::TPM_PrivateKey::algorithm_identifier(), Botan::X25519_PublicKey::algorithm_identifier(), Botan::X448_PublicKey::algorithm_identifier(), Botan::XMSS_PublicKey::algorithm_identifier(), estimated_strength(), and Botan::Public_Key::get_oid().

pkcs8_algorithm_identifier()

virtual AlgorithmIdentifier Botan::Private_Key::pkcs8_algorithm_identifier ( ) const

inlinevirtualinherited

Return the PKCS #8 AlgorithmIdentifier for this key

Note

normally this is the same as the public key identifier, but a few oddball algorithms use a different value

Reimplemented in Botan::GOST_3410_PrivateKey, and Botan::HSS_LMS_PrivateKey.

Definition at line 343 of file pk_keys.h.

{ return algorithm_identifier(); }

References Botan::Public_Key::algorithm_identifier().

Referenced by private_key_info().

private_data()

std::shared_ptr< const RSA_Private_Data > Botan::RSA_PrivateKey::private_data

(

)

const

Definition at line 227 of file rsa.cpp.

                                                                         {
   return m_private;
}

private_key_bits()

secure_vector< uint8_t > Botan::RSA_PrivateKey::private_key_bits ( ) const

overridevirtual

Return the PKCS8 private key encoding

Note

this encoding omits the outer PKCS8 algorithm identifiers and will not be portably decodable on its own. Prefer private_key_info.

Implements Botan::Private_Key.

Definition at line 231 of file rsa.cpp.

                                                              {
   return DER_Encoder()
      .start_sequence()
      .encode(static_cast<size_t>(0))
      .encode(get_n())
      .encode(get_e())
      .encode(get_d())
      .encode(get_p())
      .encode(get_q())
      .encode(get_d1())
      .encode(get_d2())
      .encode(get_c())
      .end_cons()
      .get_contents();
}

References Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), get_c(), Botan::DER_Encoder::get_contents(), get_d(), get_d1(), get_d2(), Botan::RSA_PublicKey::get_e(), Botan::RSA_PublicKey::get_n(), get_p(), get_q(), and Botan::DER_Encoder::start_sequence().

private_key_info()

secure_vector< uint8_t > Botan::Private_Key::private_key_info ( ) const

inherited

Return PKCS #8 private key encoding for this key object

Definition at line 75 of file pk_keys.cpp.

                                                           {
   const size_t PKCS8_VERSION = 0;
 
   return DER_Encoder()
      .start_sequence()
      .encode(PKCS8_VERSION)
      .encode(pkcs8_algorithm_identifier())
      .encode(private_key_bits(), ASN1_Type::OctetString)
      .end_cons()
      .get_contents();
}

References Botan::DER_Encoder::encode(), Botan::DER_Encoder::end_cons(), Botan::DER_Encoder::get_contents(), Botan::OctetString, pkcs8_algorithm_identifier(), private_key_bits(), and Botan::DER_Encoder::start_sequence().

Referenced by Botan::PKCS8::BER_encode(), Botan::PKCS8::BER_encode_encrypted_pbkdf_iter(), Botan::PKCS8::BER_encode_encrypted_pbkdf_msec(), Botan::PKCS8::PEM_encode(), and public_key().

public_data()

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

inherited

Definition at line 130 of file rsa.cpp.

                                                                      {
   return m_public;
}

References m_public.

public_key()

std::unique_ptr< Public_Key > Botan::RSA_PrivateKey::public_key ( ) const

overridevirtual

Allocate a new object for the public key associated with this private key.

Returns

public key

Implements Botan::Private_Key.

Definition at line 433 of file rsa.cpp.

                                                           {
   return std::make_unique<RSA_PublicKey>(get_n(), get_e());
}

References Botan::RSA_PublicKey::get_e(), and Botan::RSA_PublicKey::get_n().

public_key_bits()

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

overridevirtualinherited

Return the subject public key encoding of this public key

Note

this excludes the parameters field and may not be reliably decodable

Implements Botan::Public_Key.

Definition at line 209 of file rsa.cpp.

                                                        {
   std::vector<uint8_t> output;
   DER_Encoder der(output);
   der.start_sequence().encode(get_n()).encode(get_e()).end_cons();
 
   return output;
}

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

Referenced by Botan::TPM2::RSA_PrivateKey::public_key().

raw_private_key_bits()

secure_vector< uint8_t > Botan::Private_Key::raw_private_key_bits ( ) const

virtualinherited

Return the binary private key bits, with no additional encoding

Note

some algorithms (for example RSA) do not have an obvious encoding for this value due to having many different values, and thus not implement this function. The default implementation throws Not_Implemented

Reimplemented in Botan::Classic_McEliece_PrivateKey, Botan::DH_PrivateKey, Botan::Dilithium_PrivateKey, Botan::DSA_PrivateKey, Botan::EC_PrivateKey, Botan::Ed25519_PrivateKey, Botan::Ed448_PrivateKey, Botan::ElGamal_PrivateKey, Botan::FrodoKEM_PrivateKey, Botan::HSS_LMS_PrivateKey, Botan::KEX_to_KEM_Adapter_PrivateKey, Botan::Kyber_PrivateKey, Botan::SphincsPlus_PrivateKey, Botan::TPM2::PrivateKey, Botan::X25519_PrivateKey, and Botan::X448_PrivateKey.

Definition at line 87 of file pk_keys.cpp.

                                                               {
   throw Not_Implemented(algo_name() + " does not implement raw_private_key_bits");
}

References Botan::Asymmetric_Key::algo_name().

Referenced by private_key_bits().

raw_public_key_bits()

std::vector< uint8_t > Botan::RSA_PublicKey::raw_public_key_bits ( ) const

overridevirtualinherited

Return the raw public key bits (algorithm specific) with no extra encoding

For key agreements this is an alias for PK_Key_Agreement_Key::public_value.

Note

some algorithms (for example RSA) do not have an obvious encoding for this value due to having many different values, and thus throw Not_Implemented when invoking this method.

Implements Botan::Public_Key.

Reimplemented in Botan::TPM2::RSA_PublicKey.

Definition at line 205 of file rsa.cpp.

                                                            {
   throw Not_Implemented("an RSA public key does not provide a raw binary representation.");
}

remaining_operations()

virtual std::optional< uint64_t > Botan::Private_Key::remaining_operations ( ) const

inlinevirtualinherited

Retrieves the number of remaining operations if this is a stateful private key.

Returns

the number of remaining operations or std::nullopt if not applicable.

Reimplemented in Botan::HSS_LMS_PrivateKey, and Botan::XMSS_PrivateKey.

Definition at line 356 of file pk_keys.h.

{ return std::nullopt; }

stateful_operation()

virtual bool Botan::Private_Key::stateful_operation ( ) const

inlinevirtualinherited

Indicates if this key is stateful, ie that performing a private key operation requires updating the key storage.

Reimplemented in Botan::HSS_LMS_PrivateKey, and Botan::XMSS_PrivateKey.

Definition at line 349 of file pk_keys.h.

{ return false; }

subject_public_key()

std::vector< uint8_t > Botan::Public_Key::subject_public_key ( ) const

inherited

Return the SubjectPublicKeyInfo encoding of this public key

This is the subjectPublicKey field plus the algorithm-specific parameters

Definition at line 63 of file pk_keys.cpp.

                                                        {
   std::vector<uint8_t> output;
 
   DER_Encoder(output)
      .start_sequence()
      .encode(algorithm_identifier())
      .encode_octet_aligned_bitstring(public_key_bits())
      .end_cons();
 
   return output;
}

References algorithm_identifier(), Botan::DER_Encoder::encode(), Botan::DER_Encoder::encode_octet_aligned_bitstring(), Botan::DER_Encoder::end_cons(), public_key_bits(), and Botan::DER_Encoder::start_sequence().

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

supports_operation()

bool Botan::RSA_PublicKey::supports_operation ( PublicKeyOperation op ) const

overridevirtualinherited

Return true if this key could be used for the specified type of operation.

Implements Botan::Asymmetric_Key.

Reimplemented in Botan::TPM2::RSA_PublicKey.

Definition at line 182 of file rsa.cpp.

                                                                  {
   return op == PublicKeyOperation::Signature || op == PublicKeyOperation::Encryption ||
          op == PublicKeyOperation::KeyEncapsulation;
}

References Botan::Encryption, Botan::KeyEncapsulation, and Botan::Signature.

Member Data Documentation

m_public

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

protectedinherited

Definition at line 91 of file rsa.h.

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

---

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

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