Revision control
Copy as Markdown
Other Tools
/*
* (C) 2015,2017 Jack Lloyd
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/ffi.h>
#include <botan/internal/ffi_util.h>
#include <botan/aead.h>
extern "C" {
using namespace Botan_FFI;
struct botan_cipher_struct final : public botan_struct<Botan::Cipher_Mode, 0xB4A2BF9C>
{
explicit botan_cipher_struct(Botan::Cipher_Mode* x) : botan_struct(x) {}
Botan::secure_vector<uint8_t> m_buf;
};
int botan_cipher_init(botan_cipher_t* cipher, const char* cipher_name, uint32_t flags)
{
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::ENCRYPTION : Botan::DECRYPTION;
std::unique_ptr<Botan::Cipher_Mode> mode(Botan::Cipher_Mode::create(cipher_name, dir));
if(!mode)
return BOTAN_FFI_ERROR_NOT_IMPLEMENTED;
*cipher = new botan_cipher_struct(mode.release());
return BOTAN_FFI_SUCCESS;
});
}
int botan_cipher_destroy(botan_cipher_t cipher)
{
return BOTAN_FFI_CHECKED_DELETE(cipher);
}
int botan_cipher_clear(botan_cipher_t cipher)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.clear(); });
}
int botan_cipher_reset(botan_cipher_t cipher)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.reset(); });
}
int botan_cipher_output_length(botan_cipher_t cipher, size_t in_len, size_t* out_len)
{
if(out_len == nullptr)
return BOTAN_FFI_ERROR_NULL_POINTER;
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *out_len = c.output_length(in_len); });
}
int botan_cipher_query_keylen(botan_cipher_t cipher,
size_t* out_minimum_keylength,
size_t* out_maximum_keylength)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, {
*out_minimum_keylength = c.key_spec().minimum_keylength();
*out_maximum_keylength = c.key_spec().maximum_keylength();
});
}
int botan_cipher_get_keyspec(botan_cipher_t cipher,
size_t* out_minimum_keylength,
size_t* out_maximum_keylength,
size_t* out_keylength_modulo)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, 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();
});
}
int botan_cipher_set_key(botan_cipher_t cipher,
const uint8_t* key, size_t key_len)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { c.set_key(key, key_len); });
}
int botan_cipher_start(botan_cipher_t cipher_obj,
const uint8_t* nonce, size_t nonce_len)
{
return ffi_guard_thunk(__func__, [=]() -> int {
Botan::Cipher_Mode& cipher = safe_get(cipher_obj);
cipher.start(nonce, nonce_len);
cipher_obj->m_buf.reserve(cipher.update_granularity());
return BOTAN_FFI_SUCCESS;
});
}
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)
{
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->m_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.update_granularity();
BOTAN_ASSERT(cipher.update_granularity() > cipher.minimum_final_size(), "logic error");
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;
});
}
int botan_cipher_set_associated_data(botan_cipher_t cipher,
const uint8_t* ad,
size_t ad_len)
{
return BOTAN_FFI_RETURNING(Botan::Cipher_Mode, cipher, 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;
});
}
int botan_cipher_valid_nonce_length(botan_cipher_t cipher, size_t nl)
{
return BOTAN_FFI_RETURNING(Botan::Cipher_Mode, cipher, c, {
return c.valid_nonce_length(nl) ? 1 : 0;
});
}
int botan_cipher_get_default_nonce_length(botan_cipher_t cipher, size_t* nl)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *nl = c.default_nonce_length(); });
}
int botan_cipher_get_update_granularity(botan_cipher_t cipher, size_t* ug)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *ug = c.update_granularity(); });
}
int botan_cipher_get_tag_length(botan_cipher_t cipher, size_t* tl)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, { *tl = c.tag_size(); });
}
int botan_cipher_name(botan_cipher_t cipher, char* name, size_t* name_len)
{
return BOTAN_FFI_DO(Botan::Cipher_Mode, cipher, c, {
return write_str_output(name, name_len, c.name()); });
}
}