Source code
Revision control
Copy as Markdown
Other Tools
/*-
* Copyright (c) 2017-2024 Ribose Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef RNP_ELG_H_
#define RNP_ELG_H_
#include <stdint.h>
#include "crypto/rng.h"
#include "crypto/mpi.hpp"
#include "mem.h"
namespace pgp {
namespace eg {
class Signature {
public:
/* This is kept only for packet reading. Implementation MUST
* not create elgamal signatures */
mpi r{};
mpi s{};
};
class Encrypted {
public:
mpi g;
mpi m;
};
class Key {
public:
mpi p{};
mpi g{};
mpi y{};
/* secret mpi */
mpi x{};
void
clear_secret()
{
x.forget();
}
~Key()
{
clear_secret();
}
bool validate(bool secret) const noexcept;
/*
* Performs ElGamal encryption
* Result of an encryption is composed of two parts - g2k and encm
*
* @param rng initialized rnp::RNG
* @param out encryption result
* @param in plaintext to be encrypted
* @param in_len length of the plaintext
* @param key public key to be used for encryption
*
* @pre out: must be valid pointer to corresponding structure
* @pre in_len: can't be bigger than byte size of `p'
*
* @return RNP_SUCCESS
* RNP_ERROR_OUT_OF_MEMORY allocation failure
* RNP_ERROR_BAD_PARAMETERS wrong input provided
*/
rnp_result_t encrypt_pkcs1(rnp::RNG & rng,
Encrypted & out,
const rnp::secure_bytes &in) const;
/*
* Performs ElGamal decryption
*
* @param rng initialized rnp::RNG
* @param out decrypted plaintext. Must be capable of storing at least as much bytes as p
* size
* @param out_len number of plaintext bytes written will be put here
* @param in encrypted data
* @param key private key
*
* @pre out, in: must be valid pointers
* @pre out: length must be long enough to store decrypted data. Max size of
* decrypted data is equal to bytes size of `p'
*
* @return RNP_SUCCESS
* RNP_ERROR_OUT_OF_MEMORY allocation failure
* RNP_ERROR_BAD_PARAMETERS wrong input provided
*/
rnp_result_t decrypt_pkcs1(rnp::RNG & rng,
rnp::secure_bytes &out,
const Encrypted & in) const;
/*
* Generates ElGamal key
*
* @param rng pointer to PRNG
* @param key generated key
* @param keybits key bitlen
*
* @pre `keybits' > 1024
*
* @returns RNP_ERROR_BAD_PARAMETERS wrong parameters provided
* RNP_ERROR_GENERIC internal error
* RNP_SUCCESS key generated and copied to `seckey'
*/
rnp_result_t generate(rnp::RNG &rng, size_t keybits);
};
} // namespace eg
} // namespace pgp
#endif