Botan::AES_256_CTR_XOF Class Reference

#include <aes_crystals_xof.h>

Inheritance diagram for Botan::AES_256_CTR_XOF:

Public Member Functions
bool	accepts_input () const override
	AES_256_CTR_XOF ()
size_t	block_size () const override
void	clear ()
std::unique_ptr< XOF >	copy_state () const override
Key_Length_Specification	key_spec () const override
std::string	name () const override
std::unique_ptr< XOF >	new_object () const override
template<size_t count>
std::array< uint8_t, count >	output ()
template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>
T	output (size_t bytes)
void	output (std::span< uint8_t > output)
uint8_t	output_next_byte ()
std::vector< uint8_t >	output_stdvec (size_t bytes)
virtual std::string	provider () const
void	reset () override
void	start (std::span< const uint8_t > salt={}, std::span< const uint8_t > key={})
void	update (std::span< const uint8_t > input)
bool	valid_salt_length (size_t iv_length) const override
	~AES_256_CTR_XOF () override

Static Public Member Functions
static std::unique_ptr< XOF >	create (std::string_view algo_spec, std::string_view provider="")
static std::unique_ptr< XOF >	create_or_throw (std::string_view algo_spec, std::string_view provider="")
static std::vector< std::string >	providers (std::string_view algo_spec)

Detailed Description

XOF implementation for Kyber/Dilithium 90s-modes based on AES-256 in counter mode.

This is an internal class that is not meant for consumption by library users. It is therefore not registered in XOF::create().

Definition at line 26 of file aes_crystals_xof.h.

Constructor & Destructor Documentation

AES_256_CTR_XOF()

Botan::AES_256_CTR_XOF::AES_256_CTR_XOF

(

)

Definition at line 17 of file aes_crystals_xof.cpp.

: m_stream_cipher(StreamCipher::create_or_throw(name())) {}

~AES_256_CTR_XOF()

Botan::AES_256_CTR_XOF::~AES_256_CTR_XOF ( )

overridedefault

Member Function Documentation

accepts_input()

bool Botan::AES_256_CTR_XOF::accepts_input ( ) const

inlineoverridevirtual

Typically, this is true for new objects and becomes false once output() was called for the first time.

Returns

true iff calling update() is legal in the current object state

Implements Botan::XOF.

Definition at line 47 of file aes_crystals_xof.h.

{ return false; }

block_size()

size_t Botan::AES_256_CTR_XOF::block_size ( ) const

inlineoverridevirtual

Returns

the intrinsic processing block size of this XOF

Implements Botan::XOF.

Definition at line 41 of file aes_crystals_xof.h.

{ return 16; }

clear()

void Botan::XOF::clear ( )

inlineinherited

Reset the state.

Definition at line 66 of file xof.h.

                   {
         m_xof_started = false;
         reset();
      }

Referenced by Botan::Dilithium_Symmetric_Primitives_Base::H(), Botan::Dilithium_Symmetric_Primitives_Base::H(), Botan::Dilithium_Symmetric_Primitives_Base::H_256(), and Botan::FrodoKEMConstants::SHAKE_XOF().

copy_state()

std::unique_ptr< XOF > Botan::AES_256_CTR_XOF::copy_state ( ) const

overridevirtual

Return a new XOF object with the same state as *this.

If the XOF is not yet in the output phase, it efficiently allows using several messages with a common prefix. Otherwise, the copied state will produce the same output bit stream as the original object at the time of this invocation.

This function should be called clone but for consistency with other classes it is called copy_state.

Returns

new XOF object

Implements Botan::XOF.

Definition at line 38 of file aes_crystals_xof.cpp.

                                                     {
   throw Not_Implemented(fmt("Copying the state of XOF {} is not implemented", name()));
}

References Botan::fmt(), and name().

create()

std::unique_ptr< XOF > Botan::XOF::create ( std::string_view algo_spec, std::string_view provider = "" )

staticinherited

Create an instance based on a name, or return null if the algo/provider combination cannot be found. If provider is empty then best available is chosen.

Definition at line 22 of file xof.cpp.

                                                                                {
   const SCAN_Name req(algo_spec);
 
   if(!provider.empty() && provider != "base") {
      return nullptr;  // unknown provider
   }
 
#if defined(BOTAN_HAS_SHAKE_XOF)
   if(req.algo_name() == "SHAKE-128" && req.arg_count() == 0) {
      return std::make_unique<SHAKE_128_XOF>();
   }
   if(req.algo_name() == "SHAKE-256" && req.arg_count() == 0) {
      return std::make_unique<SHAKE_256_XOF>();
   }
#endif
 
   return nullptr;
}

References Botan::SCAN_Name::algo_name(), Botan::SCAN_Name::arg_count(), and Botan::XOF::provider().

Referenced by Botan::XOF::create_or_throw().

create_or_throw()

std::unique_ptr< XOF > Botan::XOF::create_or_throw ( std::string_view algo_spec, std::string_view provider = "" )

staticinherited

Create an instance based on a name If provider is empty then best available is chosen.

Parameters

algo_spec	algorithm name
provider	provider implementation to use Throws Lookup_Error if not found.

Definition at line 42 of file xof.cpp.

                                                                                         {
   if(auto xof = XOF::create(algo_spec, provider)) {
      return xof;
   }
   throw Lookup_Error("XOF", algo_spec, provider);
}

References Botan::XOF::create(), and Botan::XOF::provider().

key_spec()

Key_Length_Specification Botan::AES_256_CTR_XOF::key_spec ( ) const

overridevirtual

Returns

an object describing limits on the key size

Reimplemented from Botan::XOF.

Definition at line 34 of file aes_crystals_xof.cpp.

                                                         {
   return m_stream_cipher->key_spec();
}

name()

std::string Botan::AES_256_CTR_XOF::name ( ) const

inlineoverridevirtual

Returns

the hash function name

Implements Botan::XOF.

Definition at line 33 of file aes_crystals_xof.h.

{ return "CTR-BE(AES-256)"; }

Referenced by copy_state().

new_object()

std::unique_ptr< XOF > Botan::AES_256_CTR_XOF::new_object ( ) const

inlineoverridevirtual

Returns

new object representing the same algorithm as *this

Implements Botan::XOF.

Definition at line 45 of file aes_crystals_xof.h.

{ return std::make_unique<AES_256_CTR_XOF>(); }

output() [1/3]

template<size_t count>

std::array< uint8_t, count > Botan::XOF::output ( )

inlineinherited

Returns

the next count output bytes as a std::array<>.

Definition at line 165 of file xof.h.

                                        {
         std::array<uint8_t, count> out;
         generate_bytes(out);
         return out;
      }

output() [2/3]

template<concepts::resizable_byte_buffer T = secure_vector<uint8_t>>

T Botan::XOF::output ( size_t bytes )

inlineinherited

Returns

the next bytes output bytes as the specified container type T.

Definition at line 155 of file xof.h.

                             {
         T out(bytes);
         generate_bytes(out);
         return out;
      }

References T.

Referenced by Botan::DilithiumMessageHash::final(), Botan::Dilithium_Symmetric_Primitives_Base::H(), Botan::Dilithium_Symmetric_Primitives_Base::H_256(), Botan::FrodoMatrix::make_sample_generator(), and Botan::Kyber_Symmetric_Primitives::PRF().

output() [3/3]

void Botan::XOF::output ( std::span< uint8_t > output )

inlineinherited

Fill output with the next output bytes. The number of bytes depends on the size of output.

Definition at line 183 of file xof.h.

{ generate_bytes(output); }

output_next_byte()

uint8_t Botan::XOF::output_next_byte ( )

inlineinherited

Returns

the next single output byte

Definition at line 188 of file xof.h.

                                 {
         uint8_t out;
         generate_bytes({&out, 1});
         return out;
      }

output_stdvec()

std::vector< uint8_t > Botan::XOF::output_stdvec ( size_t bytes )

inlineinherited

Convenience overload to generate a std::vector<uint8_t>. Same as calling XOF::output<std::vector<uint8_t>>().

Returns

the next bytes output bytes as a byte vector.

Definition at line 177 of file xof.h.

{ return output<std::vector<uint8_t>>(bytes); }

provider()

std::string Botan::XOF::provider ( ) const

virtualinherited

Returns

provider information about this implementation. Default is "base", might also return "sse2", "avx2", "openssl", or some other arbitrary string.

Reimplemented in Botan::cSHAKE_XOF, and Botan::SHAKE_XOF.

Definition at line 54 of file xof.cpp.

                              {
   return "base";
}

Referenced by Botan::XOF::create(), and Botan::XOF::create_or_throw().

providers()

std::vector< std::string > Botan::XOF::providers ( std::string_view algo_spec )

staticinherited

Returns

list of available providers for this algorithm, empty if not available

Parameters

algo_spec

algorithm name

Definition at line 50 of file xof.cpp.

                                                            {
   return probe_providers_of<XOF>(algo_spec, {"base"});
}

References Botan::probe_providers_of().

reset()

void Botan::AES_256_CTR_XOF::reset ( )

overridevirtual

Clear the XOF's internal state and allow for new input.

Implements Botan::XOF.

Definition at line 21 of file aes_crystals_xof.cpp.

                            {
   m_stream_cipher->clear();
}

start()

void Botan::XOF::start ( std::span< const uint8_t > salt = {}, std::span< const uint8_t > key = {} )

inherited

Some XOFs can be parameterized with a salt and/or key. If required, this must be called before calling XOF::update().

See also

XOF::valid_salt_length()

XOF::key_spec()

Parameters

salt	a salt value to parameterize the XOF
key	a key to parameterize the XOF

Definition at line 58 of file xof.cpp.

                                                                       {
   if(!key_spec().valid_keylength(key.size())) {
      throw Invalid_Key_Length(name(), key.size());
   }
 
   if(!valid_salt_length(salt.size())) {
      throw Invalid_Argument(fmt("{} cannot accept a salt length of {}", name(), salt.size()));
   }
 
   m_xof_started = true;
   start_msg(salt, key);
}

References Botan::fmt(), Botan::XOF::key_spec(), Botan::XOF::name(), and Botan::XOF::valid_salt_length().

update()

void Botan::XOF::update ( std::span< const uint8_t > input )

inlineinherited

Add input data to the XOF's internal state

Parameters

input

the data that shall be

Definition at line 142 of file xof.h.

                                                {
         if(!m_xof_started) {
            // If the user didn't start() before the first input, we enforce
            // it with a default value, here.
            start();
         }
         add_data(input);
      }

Referenced by Botan::Dilithium_Symmetric_Primitives_Base::H(), Botan::Dilithium_Symmetric_Primitives_Base::H(), Botan::Dilithium_Symmetric_Primitives_Base::H_256(), and Botan::DilithiumMessageHash::update().

valid_salt_length()

bool Botan::AES_256_CTR_XOF::valid_salt_length ( size_t iv_length ) const

overridevirtual

Checks that the given iv_length is compatible with this XOF

Reimplemented from Botan::XOF.

Definition at line 30 of file aes_crystals_xof.cpp.

                                                              {
   return m_stream_cipher->valid_iv_length(iv_length);
}

---

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

• src/lib/xof/aes_crystals_xof/aes_crystals_xof.h
• src/lib/xof/aes_crystals_xof/aes_crystals_xof.cpp