Intel® Integrated Performance Primitives
Community support and discussions relating to developing high-performance vision, signal, security, and storage applications.
Announcements
Welcome to the Intel Community. If you get an answer you like, please mark it as an Accepted Solution to help others. Thank you!

Elliptic encryption of a text file

Caster
Beginner
612 Views

How to modify sample code to encrypt a text file.

#include <iostream> 
#include <vector> 
#include <string>
#include "ippcp.h"

using namespace std;

#pragma warning(disable : 4996)  //Ignore "Obsolete function" warning

static IppsECCPState* newStd_256_ECP(void) {
	int ctxSize;
	ippsECCPGetSize(256, &ctxSize);
	IppsECCPState* pCtx = (IppsECCPState*)(new Ipp8u[ctxSize]);
	ippsECCPInit(256, pCtx);
	ippsECCPSetStd(IppECCPStd256r1, pCtx);
	return pCtx;
} static IppsECCPPointState* newECP_256_Point(void) {
	int ctxSize;
	ippsECCPPointGetSize(256, &ctxSize);
	IppsECCPPointState* pPoint = (IppsECCPPointState*)(new Ipp8u[ctxSize]);
	ippsECCPPointInit(256, pPoint);
	return pPoint;
} static IppsBigNumState* newBN(int len, const Ipp32u* pData) {
	int ctxSize;
	ippsBigNumGetSize(len, &ctxSize);
	IppsBigNumState* pBN = (IppsBigNumState*)(new Ipp8u[ctxSize]);
	ippsBigNumInit(len, pBN);
	if (pData)       ippsSet_BN(IppsBigNumPOS, len, pData, pBN);
	return pBN;
} IppsPRNGState* newPRNG(void) {
	int ctxSize;
	ippsPRNGGetSize(&ctxSize);
	IppsPRNGState* pCtx = (IppsPRNGState*)(new Ipp8u[ctxSize]);
	ippsPRNGInit(160, pCtx);
	return pCtx;

} int main(void) {
	// define standard 256-bit EC
	IppsECCPState* pECP = newStd_256_ECP();
	// extract or use any other way to get order(ECP)
	const Ipp32u secp256r1_r[] = { 0xFC632551, 0xF3B9CAC2, 0xA7179E84, 0xBCE6FAAD, 0xFFFFFFFF, 0xFFFFFFFF, 0x00000000, 0xFFFFFFFF };
	const int ordSize = sizeof(secp256r1_r) / sizeof(Ipp32u);
	IppsBigNumState* pECPorder = newBN(ordSize, secp256r1_r);
	// define a message to be signed; let it be random, for example
	IppsPRNGState* pRandGen = newPRNG();	// 'external' PRNG
	Ipp32u tmpData[ordSize];
	ippsPRNGen(tmpData, 256, pRandGen);

	IppsBigNumState* pRandMsg = newBN(ordSize, tmpData);	// random 256-bit message
	IppsBigNumState* pMsg = newBN(ordSize, 0);				// msg to be signed
	ippsMod_BN(pRandMsg, pECPorder, pMsg);

	// declare Signer's regular and ephemeral key pair
	IppsBigNumState* regPrivate = newBN(ordSize, 0);
	IppsBigNumState* ephPrivate = newBN(ordSize, 0);
	// define Signer's ephemeral key pair
	IppsECCPPointState* regPublic = newECP_256_Point();
	IppsECCPPointState* ephPublic = newECP_256_Point();

	// generate regular & ephemeral key pairs, should be different each other
	ippsECCPGenKeyPair(regPrivate, regPublic, pECP, ippsPRNGen, pRandGen);
	ippsECCPGenKeyPair(ephPrivate, ephPublic, pECP, ippsPRNGen, pRandGen);

	//
	// signature
	//

	// set ephemeral key pair
	ippsECCPSetKeyPair(ephPrivate, ephPublic, ippFalse, pECP);
	// compure signature
	IppsBigNumState* signX = newBN(ordSize, 0);
	IppsBigNumState* signY = newBN(ordSize, 0);
	ippsECCPSignDSA(pMsg, regPrivate, signX, signY, pECP);

	//
	// verification
	//

	ippsECCPSetKeyPair(NULL, regPublic, ippTrue, pECP);
	IppECResult eccResult;
	ippsECCPVerifyDSA(pMsg, signX, signY, &eccResult, pECP);
	if (ippECValid == eccResult)
		cout << "signature verificatioin passed" << endl;
	else
		cout << "signature verificatioin failed" << endl;

	delete[](Ipp8u*)signX;
	delete[](Ipp8u*)signY;
	delete[](Ipp8u*)ephPublic;
	delete[](Ipp8u*)regPublic;
	delete[](Ipp8u*)ephPrivate;
	delete[](Ipp8u*)regPrivate;
	delete[](Ipp8u*)pRandMsg;
	delete[](Ipp8u*)pMsg;
	delete[](Ipp8u*)pRandGen;
	delete[](Ipp8u*)pECPorder;
	delete[](Ipp8u*)pECP;
	return 0;
}

 

0 Kudos
1 Reply
Abhinav_S_Intel
Moderator
557 Views

In IPP, we have API which are matched to standard. Unfortunately, the API (and std) mismatch with your use case and it's not possible to do such operation.

Reply