c4e_dlc_dsa.h File Reference

(Version 579)

Digital Signature Algorithm (DSA) in discrete logarithm (DL) domain. More...

#include "c4e_sha.h"
#include "c4e_dlc.h"
#include "c4e_gfp.h"

Include dependency graph for c4e_dlc_dsa.h:

Defines
#define	C4E_DLC_DSA_TMPID_SIGN
	Temp. space qualifier associated with c4e_dlc_dsa_sign().
#define	C4E_DLC_DSA_TMPID_VERIFY
	Temp. space qualifier associated with c4e_dlc_dsa_verify().
#define	C4E_DLC_DSA_TMPID_MAX
	Temp. space qualifier applicable to all DSA functions.
Typedefs
typedef void(*	C4eDlcDsaK2rFunc )(void C4E_RESTRICT ctx, C4E_CONST C4eElement C4E_RESTRICT k, C4eElement *C4E_RESTRICT r)
	Function which computes signature component r (one-time DSA public key respective the x-coordinate of a public ECDSA key) from the associated one-time private key `k`.
typedef void(*	C4eDlcDsaU2vFunc )(void C4E_RESTRICT ctx, C4E_CONST void C4E_RESTRICT y, C4E_CONST C4eElement C4E_RESTRICT u1, C4E_CONST C4eElement C4E_RESTRICT u2, C4eElement *C4E_RESTRICT v)
	Function which computes signature verification variable v from intermediate values and .
Functions
C4eSysStatus	c4e_dlc_dsa_sign (C4eDlcDomain C4E_RESTRICT dom, C4E_CONST C4eElement C4E_RESTRICT x, C4eHashId hid, C4E_CONST C4eArchUint8 C4E_RESTRICT digest, C4eArchDigit tmp[C4E_RESTRICT], C4eArchUint8 C4E_RESTRICT signature)
	DSA signature of a digest, according to IEEE Std 1363 (DLSP-DSA) and FIPS 186-4, with binary encoded signature.
C4eSysStatus	c4e_dlc_dsa_verify (C4eDlcDomain C4E_RESTRICT dom, C4E_CONST C4eElement C4E_RESTRICT y, C4eHashId hid, C4E_CONST C4eArchUint8 C4E_RESTRICT digest, C4E_CONST C4eArchUint8 C4E_RESTRICT signature, C4eArchSize len, C4eArchDigit tmp[C4E_RESTRICT])
	DSA signature verification, according to IEEE Std 1363 (DLVP-DSA) and FIPS 186-4, with binary encoded signature.
C4eSysStatus	c4e_dlc_dsa_unisig (void ctx, C4E_CONST C4eElement C4E_RESTRICT x, C4eElemOsp C4E_RESTRICT q, C4eDlcDsaK2rFunc fn_k2r, C4eHashId hid, C4E_CONST C4eArchUint8 C4E_RESTRICT digest, C4eArchDigit tmp[C4E_RESTRICT], C4eArchUint8 *C4E_RESTRICT signature)
	Universal [EC]DSA signing routine.
C4eSysStatus	c4e_dlc_dsa_univfy (void ctx, C4E_CONST void C4E_RESTRICT y, C4eElemOsp C4E_RESTRICT q, C4eDlcDsaU2vFunc fn_u2v, C4eHashId hid, C4E_CONST C4eArchUint8 C4E_RESTRICT digest, C4E_CONST C4eArchUint8 *C4E_RESTRICT signature, C4eArchSize len, C4eArchDigit tmp[C4E_RESTRICT])
	Universal [EC]DSA verification routine.

Detailed Description

Digital Signature Algorithm (DSA) in discrete logarithm (DL) domain.

Author:: Copyright (C) 2015 Ralf Hoppe <ralf.hoppe@ieee.org>

Version:

Id: c4e_dlc_dsa.h 579 2015-05-24 18:00:40Z ralf

Definition in file c4e_dlc_dsa.h.

Function Documentation

C4eSysStatus c4e_dlc_dsa_unisig	(	void *	ctx,
		C4E_CONST C4eElement *C4E_RESTRICT	x,
		C4eElemOsp *C4E_RESTRICT	q,
		C4eDlcDsaK2rFunc	fn_k2r,
		C4eHashId	hid,
		C4E_CONST C4eArchUint8 *C4E_RESTRICT	digest,
		C4eArchDigit	tmp[C4E_RESTRICT],
		C4eArchUint8 *C4E_RESTRICT	signature
	)

Universal [EC]DSA signing routine.

This function performs a DSA signature in any domain, using the following formulas for calculating (r,s):

$\begin{align*} r &= f(g, x, k) \bmod q \\ s &= k^{-1}(z + xr) \bmod q \end{align*}$

with z the (partial) digest, k the (random) one-time private key, x the private key and and f a domain dependent (callback) function which computes signature component r from a private key.

Attention:: The parameter q is temporary modified - so it must be writable. After function return it holds the same values as at function entry.

Precondition:

The validity of domain parameter q must be assured by the caller, either implicit or by using a domain parameter validity test function, e.g. c4e_dlc_domchk().

The validity of the private key x must be assured by the caller, either implicit or by using a private key test function, e.g. c4e_dlc_keychk_prv() in DL domain.

The required digits space (in units of C4eArchDigit) for tmp is (whichever is greater):

7U * C4E_GFP_INV_SPACE(q->val.size), or
C4E_GFP_INV_SPACE(q->val.size) plus the size required by parameter y of callback function fn_k2r.

The Random Number Generator (RNG) must be initialized at user side, then installed via function c4e_rng_install().

Bibliography:: Standard Specifications For Public-Key Cryptography. Std 1363-2000, IEEE, 2000.

Bibliography:: Digitale Signature Standard (DSS). FIPS Publication 186-4, National Institute of Standards and Technology, 2013.

Bibliography:: Public Key Cryptography For The Financial Services Industry: The Elliptic Curve Digital Signature Algorithm (ECDSA). ANSI X9.62, 1998.

Parameters:

`[in]`	ctx	Pointer to a context, which typically points to associated domain parameters (passed to callback function `fn_k2r`).
`[in]`	x	Pointer to private key `x` < `q`.
`[in]`	q	A prime divisor of group order (or group order itself) and it's length (which is also the length of one signature part).
`[in]`	fn_k2r	Function pointer (see C4eDlcDsaK2rFunc).
`[in]`	hid	Hash algorithm identifier associated with `digest` and it's length.
`[in]`	digest	Digest calculated by the caller using a hash function.
	tmp	Array of temporary space elements (see preconditions for details on size).
`[out]`	signature	Signature buffer, with implicit length of (2U * `q.len`) bytes. It is binary encoded according to IEEE Std 1363, annex E.3.1.

Returns:: Status

Return values:

	C4E_STATUS_OK	If the operation was successful.
	other	If the operation has failed.

See also:: C4eDlcDsaK2rFunc, C4eElement, c4e_dlc_dsa_sign(), C4E_ELEM_ASGN_MEM()

C4eSysStatus c4e_dlc_dsa_univfy	(	void *	ctx,
		C4E_CONST void *C4E_RESTRICT	y,
		C4eElemOsp *C4E_RESTRICT	q,
		C4eDlcDsaU2vFunc	fn_u2v,
		C4eHashId	hid,
		C4E_CONST C4eArchUint8 *C4E_RESTRICT	digest,
		C4E_CONST C4eArchUint8 *C4E_RESTRICT	signature,
		C4eArchSize	len,
		C4eArchDigit	tmp[C4E_RESTRICT]
	)

Universal [EC]DSA verification routine.

This function performs a DSA verification in any domain, using the following formulas for verifying (r,s):

$\begin{align*} u_1 &= z s^{-1} \bmod q u_2 &= r s^{-1} \bmod q v' &= f(g, y, u_1, u_2) \bmod q \\ \end{align*}$

with z the (partial) digest, (r, s) the received signature components, y the public key and f a domain dependent (callback) function which computes $ v' $ from domain parameters, the public key y and from $ u_1 $ and $ u_2 $ . Finally $ v' $ is compared with signature component $ r $ .

Attention:: The parameter q is temporary modified - so it must be writable. After function return it holds the same values as at function entry.