djn.h File Reference

A library implementing the Damgaard Jurik Nielsen cryptosystem with s=1 (Same properties as Paillier, but more efficient). based on:
libdjn - A library implementing the Paillier cryptosystem. (http://hms.isi.jhu.edu/acsc/libdjn/) More...

#include <gmp.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "powmod.h"

Include dependency graph for djn.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Classes
struct	djn_pubkey_t
struct	djn_prvkey_t

Macros
#define	PAILLIER_BITS_TO_BYTES(n)   ((n) % 8 ? (n) / 8 + 1 : (n) / 8)

Typedefs
typedef void(*	djn_get_rand_t )(void *buf, int len)

Functions
void	djn_keygen (unsigned int modulusbits, djn_pubkey_t **pub, djn_prvkey_t **prv)
void	djn_encrypt (mpz_t res, djn_pubkey_t *pub, mpz_t pt, gmp_randstate_t rnd)
void	djn_encrypt_crt (mpz_t res, djn_pubkey_t *pub, djn_prvkey_t *prv, mpz_t pt, gmp_randstate_t rnd)
void	djn_encrypt_fb (mpz_t res, djn_pubkey_t *pub, mpz_t plaintext, gmp_randstate_t rnd)
void	djn_decrypt (mpz_t res, djn_pubkey_t *pub, djn_prvkey_t *prv, mpz_t ct)
char *	djn_pubkey_to_hex (djn_pubkey_t *pub)
char *	djn_prvkey_to_hex (djn_prvkey_t *prv)
djn_pubkey_t *	djn_pubkey_from_hex (char *str)
djn_prvkey_t *	djn_prvkey_from_hex (char *str, djn_pubkey_t *pub)
void	djn_freepubkey (djn_pubkey_t *pub)
void	djn_freeprvkey (djn_prvkey_t *prv)
void	djn_pow_mod_n_crt (mpz_t res, const mpz_t b, const mpz_t e, const djn_pubkey_t *pub, const djn_prvkey_t *prv)
void	djn_pow_mod_n_squared_crt (mpz_t res, const mpz_t b, const mpz_t e, const djn_pubkey_t *pub, const djn_prvkey_t *prv)
void	djn_complete_pubkey (unsigned int modulusbits, djn_pubkey_t **pub, mpz_t n, mpz_t h)

Detailed Description

A library implementing the Damgaard Jurik Nielsen cryptosystem with s=1 (Same properties as Paillier, but more efficient). based on:
libdjn - A library implementing the Paillier cryptosystem. (http://hms.isi.jhu.edu/acsc/libdjn/)

Author

Daniel Demmler

Copyright

Copyright (C) 2015 EC SPRIDE - danie.nosp@m.l.de.nosp@m.mmler.nosp@m.@ec-.nosp@m.sprid.nosp@m.e.de

Function Documentation

void djn_complete_pubkey	(	unsigned int	modulusbits,
		djn_pubkey_t **	pub,
		mpz_t	n,
		mpz_t	h
	)

create full public key given only n and h (e.g., after a key exchange)

void djn_decrypt	(	mpz_t	res,
		djn_pubkey_t *	pub,
		djn_prvkey_t *	prv,
		mpz_t	ciphertext
	)

decrypt, using CRT, assumes res to be initialized

void djn_encrypt	(	mpz_t	res,
		djn_pubkey_t *	pub,
		mpz_t	plaintext,
		gmp_randstate_t	rnd
	)

encrypt plaintext to res

void djn_encrypt_crt	(	mpz_t	res,
		djn_pubkey_t *	pub,
		djn_prvkey_t *	prv,
		mpz_t	plaintext,
		gmp_randstate_t	rnd
	)

encrypt plaintext using crt if private key is known

void djn_encrypt_fb	(	mpz_t	res,
		djn_pubkey_t *	pub,
		mpz_t	plaintext,
		gmp_randstate_t	rnd
	)

fixed base encryption. Requires pre-computed fixed base table.

mpz_t version of encrypt_crt