ffi_cipher.cpp File Reference

#include <botan/ffi.h>
#include <botan/aead.h>
#include <botan/internal/ffi_util.h>

Go to the source code of this file.

Functions
int	botan_cipher_clear (botan_cipher_t cipher)
int	botan_cipher_destroy (botan_cipher_t cipher)
int	botan_cipher_get_default_nonce_length (botan_cipher_t cipher, size_t *nl)
int	botan_cipher_get_ideal_update_granularity (botan_cipher_t cipher, size_t *ug)
int	botan_cipher_get_keyspec (botan_cipher_t cipher, size_t *out_minimum_keylength, size_t *out_maximum_keylength, size_t *out_keylength_modulo)
int	botan_cipher_get_tag_length (botan_cipher_t cipher, size_t *tl)
int	botan_cipher_get_update_granularity (botan_cipher_t cipher, size_t *ug)
int	botan_cipher_init (botan_cipher_t *cipher, const char *cipher_name, uint32_t flags)
int	botan_cipher_name (botan_cipher_t cipher, char *name, size_t *name_len)
int	botan_cipher_output_length (botan_cipher_t cipher, size_t in_len, size_t *out_len)
int	botan_cipher_query_keylen (botan_cipher_t cipher, size_t *out_minimum_keylength, size_t *out_maximum_keylength)
int	botan_cipher_reset (botan_cipher_t cipher)
int	botan_cipher_set_associated_data (botan_cipher_t cipher, const uint8_t *ad, size_t ad_len)
int	botan_cipher_set_key (botan_cipher_t cipher, const uint8_t *key, size_t key_len)
int	botan_cipher_start (botan_cipher_t cipher_obj, const uint8_t *nonce, size_t nonce_len)
int	botan_cipher_update (botan_cipher_t cipher_obj, uint32_t flags, uint8_t output_ptr[], size_t orig_output_size, size_t *output_written, const uint8_t input_ptr[], size_t orig_input_size, size_t *input_consumed)
int	botan_cipher_valid_nonce_length (botan_cipher_t cipher, size_t nl)

Function Documentation

botan_cipher_clear()

int botan_cipher_clear

(

botan_cipher_t

hash

)

Reset the key, nonce, AD and all other state on this cipher object

Definition at line 84 of file ffi_cipher.cpp.

                                              {
   return BOTAN_FFI_VISIT(cipher, [](auto& c) { c.clear(); });
}

References BOTAN_FFI_VISIT.

botan_cipher_destroy()

int botan_cipher_destroy

(

botan_cipher_t

cipher

)

Destroy the cipher object

Returns

0 if success, error if invalid object handle

Definition at line 80 of file ffi_cipher.cpp.

                                                {
   return BOTAN_FFI_CHECKED_DELETE(cipher);
}

References BOTAN_FFI_CHECKED_DELETE.

botan_cipher_get_default_nonce_length()

int botan_cipher_get_default_nonce_length	(	botan_cipher_t	cipher,
		size_t *	nl
	)

Get the default nonce length of this cipher

Definition at line 228 of file ffi_cipher.cpp.

                                                                             {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) { *nl = c.default_nonce_length(); });
}

References BOTAN_FFI_VISIT.

botan_cipher_get_ideal_update_granularity()

int botan_cipher_get_ideal_update_granularity	(	botan_cipher_t	cipher,
		size_t *	ug
	)

Return the ideal update granularity of the cipher. This is some multiple of the update granularity, reflecting possibilities for optimization.

Definition at line 236 of file ffi_cipher.cpp.

                                                                                 {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) { *ug = c.ideal_granularity(); });
}

References BOTAN_FFI_VISIT.

botan_cipher_get_keyspec()

int botan_cipher_get_keyspec	(	botan_cipher_t	cipher,
		size_t *	min_keylen,
		size_t *	max_keylen,
		size_t *	mod_keylen
	)

Get information about the supported key lengths.

Definition at line 107 of file ffi_cipher.cpp.

                                                           {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) {
      if(out_minimum_keylength)
         *out_minimum_keylength = c.key_spec().minimum_keylength();
      if(out_maximum_keylength)
         *out_maximum_keylength = c.key_spec().maximum_keylength();
      if(out_keylength_modulo)
         *out_keylength_modulo = c.key_spec().keylength_multiple();
   });
}

References BOTAN_FFI_VISIT.

botan_cipher_get_tag_length()

int botan_cipher_get_tag_length	(	botan_cipher_t	cipher,
		size_t *	tag_size
	)

Get the tag length of the cipher (0 for non-AEAD modes)

Definition at line 240 of file ffi_cipher.cpp.

                                                                   {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) { *tl = c.tag_size(); });
}

References BOTAN_FFI_VISIT.

botan_cipher_get_update_granularity()

int botan_cipher_get_update_granularity	(	botan_cipher_t	cipher,
		size_t *	ug
	)

Return the update granularity of the cipher; botan_cipher_update must be called with blocks of this size, except for the final.

Definition at line 232 of file ffi_cipher.cpp.

                                                                           {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& /*c*/) { *ug = cipher->update_size(); });
}

References BOTAN_FFI_VISIT.

botan_cipher_init()

int botan_cipher_init	(	botan_cipher_t *	cipher,
		const char *	name,
		uint32_t	flags
	)

Initialize a cipher object

Definition at line 63 of file ffi_cipher.cpp.

                                                                                       {
   return ffi_guard_thunk(__func__, [=]() -> int {
      const bool encrypt_p = ((flags & BOTAN_CIPHER_INIT_FLAG_MASK_DIRECTION) == BOTAN_CIPHER_INIT_FLAG_ENCRYPT);
      const Botan::Cipher_Dir dir = encrypt_p ? Botan::Cipher_Dir::Encryption : Botan::Cipher_Dir::Decryption;
 
      std::unique_ptr<Botan::Cipher_Mode> mode(Botan::Cipher_Mode::create(cipher_name, dir));
      if(!mode) {
         return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
      }
 
      const size_t update_size = ffi_choose_update_size(*mode);
 
      *cipher = new botan_cipher_struct(std::move(mode), update_size);
      return BOTAN_FFI_SUCCESS;
   });
}

References BOTAN_CIPHER_INIT_FLAG_ENCRYPT, BOTAN_CIPHER_INIT_FLAG_MASK_DIRECTION, BOTAN_FFI_ERROR_NOT_IMPLEMENTED, BOTAN_FFI_SUCCESS, Botan::Cipher_Mode::create(), Botan::Decryption, Botan::Encryption, and Botan_FFI::ffi_guard_thunk().

botan_cipher_name()

int botan_cipher_name	(	botan_cipher_t	cipher,
		char *	name,
		size_t *	name_len
	)

Return the name of the cipher object

Definition at line 244 of file ffi_cipher.cpp.

                                                                           {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) { return write_str_output(name, name_len, c.name()); });
}

References BOTAN_FFI_VISIT, name, and Botan_FFI::write_str_output().

botan_cipher_output_length()

int botan_cipher_output_length	(	botan_cipher_t	cipher,
		size_t	in_len,
		size_t *	out_len
	)

Return the output length of this cipher, for a particular input length.

Definition at line 92 of file ffi_cipher.cpp.

                                                                                      {
   if(out_len == nullptr) {
      return BOTAN_FFI_ERROR_NULL_POINTER;
   }
 
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) { *out_len = c.output_length(in_len); });
}

References BOTAN_FFI_ERROR_NULL_POINTER, and BOTAN_FFI_VISIT.

botan_cipher_query_keylen()

int botan_cipher_query_keylen	(	botan_cipher_t	cipher,
		size_t *	out_minimum_keylength,
		size_t *	out_maximum_keylength
	)

Get information about the key lengths. Prefer botan_cipher_get_keyspec

Definition at line 100 of file ffi_cipher.cpp.

                                                                                                                   {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) {
      *out_minimum_keylength = c.key_spec().minimum_keylength();
      *out_maximum_keylength = c.key_spec().maximum_keylength();
   });
}

References BOTAN_FFI_VISIT.

botan_cipher_reset()

int botan_cipher_reset

(

botan_cipher_t

cipher

)

Reset the message specific state for this cipher. Without resetting the keys, this resets the nonce, and any state associated with any message bits that have been processed so far.

It is conceptually equivalent to calling botan_cipher_clear followed by botan_cipher_set_key with the original key.

Definition at line 88 of file ffi_cipher.cpp.

                                              {
   return BOTAN_FFI_VISIT(cipher, [](auto& c) { c.reset(); });
}

References BOTAN_FFI_VISIT.

botan_cipher_set_associated_data()

int botan_cipher_set_associated_data	(	botan_cipher_t	cipher,
		const uint8_t *	ad,
		size_t	ad_len
	)

Set the associated data. Will fail if cipher is not an AEAD

Definition at line 214 of file ffi_cipher.cpp.

                                                                                              {
   return BOTAN_FFI_VISIT(cipher, [=](auto& c) {
      if(Botan::AEAD_Mode* aead = dynamic_cast<Botan::AEAD_Mode*>(&c)) {
         aead->set_associated_data(ad, ad_len);
         return BOTAN_FFI_SUCCESS;
      }
      return BOTAN_FFI_ERROR_BAD_PARAMETER;
   });
}

References BOTAN_FFI_ERROR_BAD_PARAMETER, BOTAN_FFI_SUCCESS, and BOTAN_FFI_VISIT.

botan_cipher_set_key()

int botan_cipher_set_key	(	botan_cipher_t	cipher,
		const uint8_t *	key,
		size_t	key_len
	)

Set the key for this cipher object

Definition at line 121 of file ffi_cipher.cpp.

                                                                                    {
   return BOTAN_FFI_VISIT(cipher, [=](auto& c) { c.set_key(key, key_len); });
}

References BOTAN_FFI_VISIT.

botan_cipher_start()

int botan_cipher_start	(	botan_cipher_t	cipher,
		const uint8_t *	nonce,
		size_t	nonce_len
	)

Begin processing a new message using the provided nonce

Definition at line 125 of file ffi_cipher.cpp.

                                                                                          {
   return ffi_guard_thunk(__func__, [=]() -> int {
      Botan::Cipher_Mode& cipher = safe_get(cipher_obj);
      cipher.start(nonce, nonce_len);
      return BOTAN_FFI_SUCCESS;
   });
}

References BOTAN_FFI_SUCCESS, Botan_FFI::ffi_guard_thunk(), Botan_FFI::safe_get(), and Botan::Cipher_Mode::start().

botan_cipher_update()

int botan_cipher_update	(	botan_cipher_t	cipher,
		uint32_t	flags,
		uint8_t	output[],
		size_t	output_size,
		size_t *	output_written,
		const uint8_t	input_bytes[],
		size_t	input_size,
		size_t *	input_consumed
	)

Encrypt some data

Definition at line 133 of file ffi_cipher.cpp.

                                                {
   return ffi_guard_thunk(__func__, [=]() -> int {
      size_t input_size = orig_input_size;
      size_t output_size = orig_output_size;
      const uint8_t* input = input_ptr;
      uint8_t* output = output_ptr;
 
      using namespace Botan;
      Cipher_Mode& cipher = safe_get(cipher_obj);
      secure_vector<uint8_t>& mbuf = cipher_obj->buf();
 
      const bool final_input = (flags & BOTAN_CIPHER_UPDATE_FLAG_FINAL);
 
      if(final_input) {
         mbuf.assign(input, input + input_size);
         *input_consumed = input_size;
         *output_written = 0;
 
         try {
            cipher.finish(mbuf);
         } catch(Invalid_Authentication_Tag&) {
            return BOTAN_FFI_ERROR_BAD_MAC;
         }
 
         *output_written = mbuf.size();
 
         if(mbuf.size() <= output_size) {
            copy_mem(output, mbuf.data(), mbuf.size());
            mbuf.clear();
            return BOTAN_FFI_SUCCESS;
         }
 
         return -1;
      }
 
      if(input_size == 0) {
         // Currently must take entire buffer in this case
         *output_written = mbuf.size();
         if(output_size >= mbuf.size()) {
            copy_mem(output, mbuf.data(), mbuf.size());
            mbuf.clear();
            return BOTAN_FFI_SUCCESS;
         }
 
         return -1;
      }
 
      const size_t ud = cipher_obj->update_size();
 
      mbuf.resize(ud);
      size_t taken = 0, written = 0;
 
      while(input_size >= ud && output_size >= ud) {
         // FIXME we can use process here and avoid the copy
         copy_mem(mbuf.data(), input, ud);
         cipher.update(mbuf);
 
         input_size -= ud;
         copy_mem(output, mbuf.data(), ud);
         input += ud;
         taken += ud;
 
         output_size -= ud;
         output += ud;
         written += ud;
      }
 
      *output_written = written;
      *input_consumed = taken;
 
      return BOTAN_FFI_SUCCESS;
   });
}

References BOTAN_CIPHER_UPDATE_FLAG_FINAL, BOTAN_FFI_ERROR_BAD_MAC, BOTAN_FFI_SUCCESS, Botan_FFI::ffi_guard_thunk(), Botan::Cipher_Mode::finish(), Botan_FFI::safe_get(), and Botan::Cipher_Mode::update().

botan_cipher_valid_nonce_length()

int botan_cipher_valid_nonce_length	(	botan_cipher_t	cipher,
		size_t	nl
	)

Return if the specified nonce length is valid for this cipher

Definition at line 224 of file ffi_cipher.cpp.

                                                                      {
   return BOTAN_FFI_VISIT(cipher, [=](const auto& c) { return c.valid_nonce_length(nl) ? 1 : 0; });
}

References BOTAN_FFI_VISIT.