Botan::EMSA_PKCS1v15 Class Reference

#include <emsa_pkcs1.h>

Inheritance diagram for Botan::EMSA_PKCS1v15:

Public Member Functions
EMSA *	clone () override
AlgorithmIdentifier	config_for_x509 (const Private_Key &key, const std::string &cert_hash_name) const override
	EMSA_PKCS1v15 (HashFunction *hash)
secure_vector< uint8_t >	encoding_of (const secure_vector< uint8_t > &, size_t, RandomNumberGenerator &rng) override
std::string	name () const override
secure_vector< uint8_t >	raw_data () override
void	update (const uint8_t[], size_t) override
bool	verify (const secure_vector< uint8_t > &, const secure_vector< uint8_t > &, size_t) override

Detailed Description

PKCS #1 v1.5 signature padding aka PKCS #1 block type 1 aka EMSA3 from IEEE 1363

Definition at line 23 of file emsa_pkcs1.h.

Constructor & Destructor Documentation

EMSA_PKCS1v15()

Botan::EMSA_PKCS1v15::EMSA_PKCS1v15 ( HashFunction *  hash )

explicit

Parameters

hash	the hash function to use

Definition at line 105 of file emsa_pkcs1.cpp.

                                               : m_hash(hash)
   {
   m_hash_id = pkcs_hash_id(m_hash->name());
   }

Member Function Documentation

clone()

EMSA * Botan::EMSA_PKCS1v15::clone ( )

inlineoverridevirtual

Returns

a new object representing the same encoding method as *this

Implements Botan::EMSA.

Definition at line 31 of file emsa_pkcs1.h.

{ return new EMSA_PKCS1v15(m_hash->clone()); }

config_for_x509()

AlgorithmIdentifier Botan::EMSA_PKCS1v15::config_for_x509 ( const Private_Key &  key, const std::string &  cert_hash_name  ) const

overridevirtual

Prepare sig_algo for use in choose_sig_format for x509 certs

Parameters

key	used for checking compatibility with the encoding scheme
cert_hash_name	is checked to equal the hash for the encoding

Returns

algorithm identifier to signatures created using this key, padding method and hash.

Reimplemented from Botan::EMSA.

Definition at line 86 of file emsa_pkcs1.cpp.

   {
   if(cert_hash_name != m_hash->name())
      throw Invalid_Argument("Hash function from opts and hash_fn argument"
         " need to be identical");
   // check that the signature algorithm and the padding scheme fit
   if(!sig_algo_and_pad_ok(key.algo_name(), "EMSA3"))
      {
      throw Invalid_Argument("Encoding scheme with canonical name EMSA3"
         " not supported for signature algorithm " + key.algo_name());
      }
 
   // for RSA PKCSv1.5 parameters "SHALL" be NULL
 
   const OID oid = OID::from_string(key.algo_name() + "/" + name());
   return AlgorithmIdentifier(oid, AlgorithmIdentifier::USE_NULL_PARAM);
   }

References Botan::Public_Key::algo_name(), Botan::OID::from_string(), name(), Botan::sig_algo_and_pad_ok(), and Botan::AlgorithmIdentifier::USE_NULL_PARAM.

encoding_of()

secure_vector< uint8_t > Botan::EMSA_PKCS1v15::encoding_of ( const secure_vector< uint8_t > &  msg, size_t  output_bits, RandomNumberGenerator &  rng  )

overridevirtual

Return the encoding of a message

Parameters

msg	the result of raw_data()
output_bits	the desired output bit size
rng	a random number generator

Returns

encoded signature

Implements Botan::EMSA.

Definition at line 57 of file emsa_pkcs1.cpp.

   {
   if(msg.size() != m_hash->output_length())
      throw Encoding_Error("EMSA_PKCS1v15::encoding_of: Bad input length");
 
   return emsa3_encoding(msg, output_bits,
                         m_hash_id.data(), m_hash_id.size());
   }

name()

std::string Botan::EMSA_PKCS1v15::name ( ) const

inlineoverridevirtual

Returns

the SCAN name of the encoding/padding scheme

Implements Botan::EMSA.

Definition at line 43 of file emsa_pkcs1.h.

         { return "EMSA3(" + m_hash->name() + ")"; }

Referenced by config_for_x509().

raw_data()

secure_vector< uint8_t > Botan::EMSA_PKCS1v15::raw_data ( )

overridevirtual

Returns

raw hash

Implements Botan::EMSA.

Definition at line 51 of file emsa_pkcs1.cpp.

   {
   return m_hash->final();
   }

update()

void Botan::EMSA_PKCS1v15::update ( const uint8_t  input[], size_t  length  )

overridevirtual

Add more data to the signature computation

Parameters

input	some data
length	length of input in bytes

Implements Botan::EMSA.

Definition at line 46 of file emsa_pkcs1.cpp.

   {
   m_hash->update(input, length);
   }

verify()

bool Botan::EMSA_PKCS1v15::verify ( const secure_vector< uint8_t > &  coded, const secure_vector< uint8_t > &  raw, size_t  key_bits  )

overridevirtual

Verify the encoding

Parameters

coded	the received (coded) message representative
raw	the computed (local, uncoded) message representative
key_bits	the size of the key in bits

Returns

true if coded is a valid encoding of raw, otherwise false

Implements Botan::EMSA.

Definition at line 68 of file emsa_pkcs1.cpp.

   {
   if(raw.size() != m_hash->output_length())
      return false;
 
   try
      {
      return (coded == emsa3_encoding(raw, key_bits,
                                      m_hash_id.data(), m_hash_id.size()));
      }
   catch(...)
      {
      return false;
      }
   }

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

• src/lib/pk_pad/emsa_pkcs1/emsa_pkcs1.h
• src/lib/pk_pad/emsa_pkcs1/emsa_pkcs1.cpp