Botan::PK_Signer Class Reference

#include <pubkey.h>

Public Member Functions
	PK_Signer (const Private_Key &key, const std::string &emsa, Signature_Format format=IEEE_1363, Fault_Protection prot=ENABLE_FAULT_PROTECTION)
void	set_output_format (Signature_Format format)
SecureVector< byte >	sign_message (const byte in[], size_t length, RandomNumberGenerator &rng)
SecureVector< byte >	sign_message (const MemoryRegion< byte > &in, RandomNumberGenerator &rng)
SecureVector< byte >	signature (RandomNumberGenerator &rng)
void	update (byte in)
void	update (const byte in[], size_t length)
void	update (const MemoryRegion< byte > &in)
	~PK_Signer ()

Detailed Description

Public Key Signer. Use the sign_message() functions for small messages. Use multiple calls update() to process large messages and generate the signature by finally calling signature().

Definition at line 123 of file pubkey.h.

Constructor & Destructor Documentation

PK_Signer()

Botan::PK_Signer::PK_Signer	(	const Private_Key &	key,
		const std::string &	emsa,
		Signature_Format	format = IEEE_1363,
		Fault_Protection	prot = ENABLE_FAULT_PROTECTION )

Construct a PK Signer.

Parameters

key	the key to use inside this signer
emsa	the EMSA to use An example would be "EMSA1(SHA-224)".
format	the signature format to use
prot	says if fault protection should be enabled

Definition at line 128 of file pubkey.cpp.

   {
   Algorithm_Factory::Engine_Iterator i(global_state().algorithm_factory());
 
   op = 0;
   verify_op = 0;
 
   while(const Engine* engine = i.next())
      {
      if(!op)
         op = engine->get_signature_op(key);
 
      if(!verify_op && prot == ENABLE_FAULT_PROTECTION)
         verify_op = engine->get_verify_op(key);
 
      if(op && (verify_op || prot == DISABLE_FAULT_PROTECTION))
         break;
      }
 
   if(!op || (!verify_op && prot == ENABLE_FAULT_PROTECTION))
      throw Lookup_Error("Signing with " + key.algo_name() + " not supported");
 
   emsa = get_emsa(emsa_name);
   sig_format = format;
   }

References Botan::Public_Key::algo_name(), Botan::DISABLE_FAULT_PROTECTION, Botan::ENABLE_FAULT_PROTECTION, Botan::get_emsa(), Botan::global_state(), Botan::Lookup_Error::Lookup_Error(), and Botan::Algorithm_Factory::Engine_Iterator::next().

Referenced by Botan::choose_sig_format(), and Botan::get_pk_signer().

~PK_Signer()

Botan::PK_Signer::~PK_Signer ( )

inline

Definition at line 192 of file pubkey.h.

{ delete op; delete verify_op; delete emsa; }

Member Function Documentation

set_output_format()

void Botan::PK_Signer::set_output_format ( Signature_Format format )

inline

Set the output format of the signature.

Parameters

format

the signature format to use

Definition at line 177 of file pubkey.h.

{ sig_format = format; }

sign_message() [1/2]

SecureVector< byte > Botan::PK_Signer::sign_message	(	const byte	in[],
		size_t	length,
		RandomNumberGenerator &	rng )

Sign a message.

Parameters

in	the message to sign as a byte array
length	the length of the above byte array
rng	the rng to use

Returns

signature

Definition at line 160 of file pubkey.cpp.

   {
   update(msg, length);
   return signature(rng);
   }

References signature(), and update().

Referenced by Botan::Certificate_Verify::Certificate_Verify(), Botan::EAC1_1_ADO::make_signed(), Botan::EAC1_1_gen_CVC< Derived >::make_signed(), Botan::X509_Object::make_signed(), sign_message(), and Botan::KeyPair::signature_consistency_check().

sign_message() [2/2]

SecureVector< byte > Botan::PK_Signer::sign_message ( const MemoryRegion< byte > & in, RandomNumberGenerator & rng )

inline

Sign a message.

Parameters

in	the message to sign
rng	the rng to use

Returns

signature

Definition at line 142 of file pubkey.h.

         { return sign_message(&in[0], in.size(), rng); }

References sign_message(), and Botan::MemoryRegion< T >::size().

signature()

SecureVector< byte > Botan::PK_Signer::signature

(

RandomNumberGenerator &

rng

)

Get the signature of the so far processed message (provided by the calls to update()).

Parameters

rng	the rng to use

Returns

signature of the total message

Definition at line 210 of file pubkey.cpp.

   {
   SecureVector<byte> encoded = emsa->encoding_of(emsa->raw_data(),
                                                  op->max_input_bits(),
                                                  rng);
 
   SecureVector<byte> plain_sig = op->sign(&encoded[0], encoded.size(), rng);
 
   BOTAN_ASSERT(self_test_signature(encoded, plain_sig),
                "PK_Signer consistency check failed");
 
   if(op->message_parts() == 1 || sig_format == IEEE_1363)
      return plain_sig;
 
   if(sig_format == DER_SEQUENCE)
      {
      if(plain_sig.size() % op->message_parts())
         throw Encoding_Error("PK_Signer: strange signature size found");
      const size_t SIZE_OF_PART = plain_sig.size() / op->message_parts();
 
      std::vector<BigInt> sig_parts(op->message_parts());
      for(size_t j = 0; j != sig_parts.size(); ++j)
         sig_parts[j].binary_decode(&plain_sig[SIZE_OF_PART*j], SIZE_OF_PART);
 
      return DER_Encoder()
         .start_cons(SEQUENCE)
            .encode_list(sig_parts)
         .end_cons()
      .get_contents();
      }
   else
      throw Encoding_Error("PK_Signer: Unknown signature format " +
                           to_string(sig_format));
   }

References BOTAN_ASSERT, Botan::DER_SEQUENCE, Botan::DER_Encoder::encode_list(), Botan::Encoding_Error::Encoding_Error(), Botan::DER_Encoder::end_cons(), Botan::DER_Encoder::get_contents(), Botan::IEEE_1363, Botan::SEQUENCE, Botan::MemoryRegion< T >::size(), Botan::DER_Encoder::start_cons(), and Botan::to_string().

Referenced by Botan::Server_Key_Exchange::Server_Key_Exchange(), Botan::CMS_Encoder::sign(), and sign_message().

update() [1/3]

void Botan::PK_Signer::update ( byte in )

inline

Add a message part (single byte).

Parameters

in	the byte to add

Definition at line 150 of file pubkey.h.

{ update(&in, 1); }

References update().

Referenced by Botan::Server_Key_Exchange::Server_Key_Exchange(), Botan::CMS_Encoder::sign(), sign_message(), and update().

update() [2/3]

void Botan::PK_Signer::update	(	const byte	in[],
		size_t	length )

Add a message part.

Parameters

in	the message part to add as a byte array
length	the length of the above byte array

Definition at line 170 of file pubkey.cpp.

   {
   emsa->update(in, length);
   }

update() [3/3]

void Botan::PK_Signer::update ( const MemoryRegion< byte > & in )

inline

Add a message part.

Parameters

in	the message part to add

Definition at line 163 of file pubkey.h.

{ update(&in[0], in.size()); }

References Botan::MemoryRegion< T >::size(), and update().

Referenced by update().

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

• src/pubkey/pubkey.h
• src/pubkey/pubkey.cpp