Shipovnik signature scheme

Typedefs
typedef struct shipovnik_st *	shipovnik_t
	Shipovnik algorithm instance handle. More...

Enumerations
enum	shipovnik_parameterset_t { shipovnik_default , shipovnik_last }
	Possible shipovnik parameters sets. More...

Functions
PQLR_API shipovnik_t	shipovnik_new (shipovnik_parameterset_t parameterset)
	Creates new shipovnik instance with selected parameter set. More...
PQLR_API void	shipovnik_free (shipovnik_t shipovnik)
	Frees shipovnik instance and all corresponding resources. More...
PQLR_API shipovnik_t	shipovnik_duplicate (const shipovnik_t shipovnik)
	Duplicates context of shipovnik instance. More...
PQLR_API pqlr_t	shipovnik_to_pqlr (shipovnik_t shipovnik)
	Casts shipovnik instance to pqlr instance. More...
PQLR_API size_t	shipovnik_get_public_key_bytes_len (const shipovnik_t shipovnik)
	Obtains public key buffer length in bytes for current shipovnik instance. More...
PQLR_API size_t	shipovnik_get_secret_key_bytes_len (const shipovnik_t shipovnik)
	Obtains secret key buffer length in bytes for current shipovnik instance. More...
PQLR_API size_t	shipovnik_get_signature_bytes_len (shipovnik_t shipovnik)
	Obtains signature buffer length in bytes for current shipovnik instance. More...
PQLR_API void	shipovnik_generate_keys (const shipovnik_t shipovnik, uint8_t *result_sk, uint8_t *result_pk)
	Generates random secret key and public key for given context. More...
PQLR_API void	shipovnik_sign (const shipovnik_t shipovnik, const uint8_t *sk, const uint8_t *msg, size_t msg_len, uint8_t *result_sig, size_t *result_sig_len)
	Generates signature for given message according to context and secret key. More...
PQLR_API int	shipovnik_verify (const shipovnik_t shipovnik, const uint8_t *pk, const uint8_t *sig, size_t sig_len, const uint8_t *msg, size_t msg_len)
	Verifies that given signature is the signature of given message. More...

Detailed Description

This module provides Shipovnik algorithm, whose security is implemented using operations on error-correcting codes defined on a final two-element prime field.

General usage

At first, initialize algorithm's instance with parameters you want with shipovnik_new(). After that, you can generate secret and public keys using shipovnik_generate_keys, or sign your message with shipovnik_sign, or verify message wasn't changed with shipovnik_verify. You are able to interact with this algorithm likewise pqlr_t instance (change error handler, source of entropy input, e.t.c) via shipovnik_to_pqlr() call.

After there is no more need in signature scheme it's resources must be made free by shipovnik_free.

In order to use any Shipovnik signature scheme functions, add the following include:

#include <pqlr/shipovnik/shipovnik.h>

Example code is listed below:

#include <pqlr/shipovnik/shipovnik.h>
 
#include <stdlib.h>
 
void use_new(void)
{
    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
 
    // free resources
    shipovnik_free(shipovnik);
}
 
 
void use_generate_keys(void)
{
    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
    const size_t sk_len = shipovnik_get_secret_key_bytes_len(shipovnik);
    const size_t pk_len = shipovnik_get_public_key_bytes_len(shipovnik);
    uint8_t* sk = (uint8_t*)calloc(sk_len, sizeof(uint8_t));
    uint8_t* pk = (uint8_t*)calloc(pk_len, sizeof(uint8_t));
    shipovnik_generate_keys(shipovnik, sk, pk);
 
    // free resources
    free(pk);
    free(sk);
    shipovnik_free(shipovnik);
}
 
 
void use_sign(void)
{
    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
    const size_t sk_len = shipovnik_get_secret_key_bytes_len(shipovnik);
    // get secret key from somewhere
    uint8_t* sk = (uint8_t*)calloc(sk_len, sizeof(uint8_t));
    size_t sig_len = shipovnik_get_signature_bytes_len(shipovnik);
    uint8_t* sig = (uint8_t*)calloc(sig_len, sizeof(uint8_t));
    unsigned char msg[] = "test";
    shipovnik_sign(shipovnik, sk, msg, sizeof(msg), sig, &sig_len);
 
    // free resources
    free(sig);
    free(sk);
    shipovnik_free(shipovnik);
}
 
 
void use_verify(void)
{
    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
    const size_t pk_len = shipovnik_get_public_key_bytes_len(shipovnik);
    const size_t sig_len = shipovnik_get_signature_bytes_len(shipovnik);
    // get public key and signature from somewhere
    uint8_t* pk = (uint8_t*)calloc(pk_len, sizeof(uint8_t));
    uint8_t* sig = (uint8_t*)calloc(sig_len, sizeof(uint8_t));
    unsigned char msg[] = "test";
    int res = shipovnik_verify(shipovnik, pk, sig, sig_len, msg, sizeof(msg));
 
    // free resources
    free(sig);
    free(pk);
    shipovnik_free(shipovnik);
}
 
 
int main(void)
{
    use_new();
    use_generate_keys();
    use_sign();
    use_verify();
}

Typedef Documentation

shipovnik_t

typedef struct shipovnik_st* shipovnik_t

Shipovnik algorithm instance handle.

Note

It could be casted to pqlr_t instance linked to this handle

See also

shipovnik_to_pqlr

Enumeration Type Documentation

shipovnik_parameterset_t

enum shipovnik_parameterset_t

Possible shipovnik parameters sets.

Enumerator
shipovnik_default
shipovnik_last

Function Documentation

shipovnik_duplicate()

PQLR_API shipovnik_t shipovnik_duplicate

(

const shipovnik_t

shipovnik

)

Duplicates context of shipovnik instance.

Parameters

shipovnik

instance to duplicate

Returns

new instance with a duplicated context

shipovnik_free()

PQLR_API void shipovnik_free

(

shipovnik_t

shipovnik

)

Frees shipovnik instance and all corresponding resources.

Parameters

[in]

shipovnik

instance to free

See also

shipovnik_t

shipovnik_new

shipovnik_generate_keys()

PQLR_API void shipovnik_generate_keys	(	const shipovnik_t	shipovnik,
		uint8_t *	result_sk,
		uint8_t *	result_pk
	)

Generates random secret key and public key for given context.

Usage:

    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
    const size_t sk_len = shipovnik_get_secret_key_bytes_len(shipovnik);
    const size_t pk_len = shipovnik_get_public_key_bytes_len(shipovnik);
    uint8_t* sk = (uint8_t*)calloc(sk_len, sizeof(uint8_t));
    uint8_t* pk = (uint8_t*)calloc(pk_len, sizeof(uint8_t));
    shipovnik_generate_keys(shipovnik, sk, pk);

Parameters

[in]	shipovnik	Instance of shipovnik created with shipovnik_new(). If NULL, the fatal error occurs.
[out]	result_sk	Contiguous array to receive secret key, of size shipovnik_get_secret_key_bytes_len. If NULL, the fatal error occurs.
[out]	result_pk	Contiguous array to receive public key, of size shipovnik_get_public_key_bytes_len. If NULL, the fatal error occurs.

See also

shipovnik_new

shipovnik_get_secret_key_bytes_len

shipovnik_get_public_key_bytes_len

shipovnik_get_public_key_bytes_len()

PQLR_API size_t shipovnik_get_public_key_bytes_len

(

const shipovnik_t

shipovnik

)

Obtains public key buffer length in bytes for current shipovnik instance.

Parameters

[in]

shipovnik

initialized shipovnik instance

See also

shipovnik_t

shipovnik_new

Returns

public key buffer length in bytes

shipovnik_get_secret_key_bytes_len()

PQLR_API size_t shipovnik_get_secret_key_bytes_len

(

const shipovnik_t

shipovnik

)

Obtains secret key buffer length in bytes for current shipovnik instance.

Parameters

[in]

shipovnik

initialized shipovnik instance

See also

shipovnik_t

shipovnik_new

Returns

secret key buffer length in bytes

shipovnik_get_signature_bytes_len()

PQLR_API size_t shipovnik_get_signature_bytes_len

(

shipovnik_t

shipovnik

)

Obtains signature buffer length in bytes for current shipovnik instance.

Parameters

[in]

shipovnik

initialized shipovnik instance

See also

shipovnik_t

shipovnik_new

Returns

signature buffer max length in bytes

shipovnik_new()

PQLR_API shipovnik_t shipovnik_new

(

shipovnik_parameterset_t

parameterset

)

Creates new shipovnik instance with selected parameter set.

Usage:

    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);

Parameters

[in]

parameterset

available set of parameters for shipovnik algorithm

Returns

initialized shipovnik instance or NULL if out of memory

shipovnik_sign()

PQLR_API void shipovnik_sign	(	const shipovnik_t	shipovnik,
		const uint8_t *	sk,
		const uint8_t *	msg,
		size_t	msg_len,
		uint8_t *	result_sig,
		size_t *	result_sig_len
	)

Generates signature for given message according to context and secret key.

Usage:

    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
    const size_t sk_len = shipovnik_get_secret_key_bytes_len(shipovnik);
    // get secret key from somewhere
    uint8_t* sk = (uint8_t*)calloc(sk_len, sizeof(uint8_t));
    size_t sig_len = shipovnik_get_signature_bytes_len(shipovnik);
    uint8_t* sig = (uint8_t*)calloc(sig_len, sizeof(uint8_t));
    unsigned char msg[] = "test";
    shipovnik_sign(shipovnik, sk, msg, sizeof(msg), sig, &sig_len);

Note

the maximum length of a signature is given by get_signature_bytes_len, while the actual length may be smaller and is returned in sig_len.

Parameters

[in]	shipovnik	Instance of shipovnik created with shipovnik_new(). If NULL, the fatal error occurs.
[in]	sk	Secret key, the contiguous array of size shipovnik_get_secret_key_bytes_len. If NULL, the fatal error occurs.
[in]	msg	Message to generate signature of, the contiguous array. If NULL, the fatal error occurs.
[in]	msg_len	The length of a message in bytes. If 0, the fatal error occurs.
[out]	result_sig	Contiguous array to receive signature, of size shipovnik_get_signature_bytes_len. If NULL, the fatal error occurs.
[out]	result_sig_len	The result signature size.

See also

shipovnik_get_secret_key_bytes_len

shipovnik_get_signature_bytes_len

shipovnik_to_pqlr()

PQLR_API pqlr_t shipovnik_to_pqlr

(

shipovnik_t

shipovnik

)

Casts shipovnik instance to pqlr instance.

Parameters

[in]

shipovnik

initialized shipovnik instance

Note

this pqlr instance will be released by shipovnik_free

See also

shipovnik_t

pqlr_t

shipovnik_free

Returns

operable pqlr instance or NULL if shipovnik is NULL

shipovnik_verify()

PQLR_API int shipovnik_verify	(	const shipovnik_t	shipovnik,
		const uint8_t *	pk,
		const uint8_t *	sig,
		size_t	sig_len,
		const uint8_t *	msg,
		size_t	msg_len
	)

Verifies that given signature is the signature of given message.

Usage:

    shipovnik_t shipovnik = shipovnik_new(shipovnik_default);
    const size_t pk_len = shipovnik_get_public_key_bytes_len(shipovnik);
    const size_t sig_len = shipovnik_get_signature_bytes_len(shipovnik);
    // get public key and signature from somewhere
    uint8_t* pk = (uint8_t*)calloc(pk_len, sizeof(uint8_t));
    uint8_t* sig = (uint8_t*)calloc(sig_len, sizeof(uint8_t));
    unsigned char msg[] = "test";
    int res = shipovnik_verify(shipovnik, pk, sig, sig_len, msg, sizeof(msg));

Parameters

[in]	shipovnik	Context, initialized with shipovnik_new(). If NULL, the fatal error occurs.
[in]	pk	Public key, the contiguous array of size shipovnik_get_public_key_bytes_len. If NULL, the fatal error occurs.
[in]	sig	Signature, the contiguous array of size ‘shipovnik_get_signature_bytes_len’. If NULL, the fatal error occurs.
[in]	msg	Message to verify signature of, the contiguous array. If NULL, the fatal error occurs.
[in]	msg_len	The length of a message in bytes. If 0, the fatal error occurs.
[in]	sig_len	The length of a signature in bytes.

Returns

0 if given signature is the signature of given message, otherwise non-zero value.

See also

shipovnik_get_signature_bytes_len

shipovnik_get_public_key_bytes_len