Developer Reference


Functions for Creation of Cryptographic Contexts

The section presents source code for creation of some cryptographic contexts.


Contents of the header file (
) declaring functions for creation of some cryptographic contexts are presented below:
#if !defined _CPOBJS_H_ #define _CPOBJS_H_ // // create new of some ippCP 'objects' // #include "ippcp.h" #include <stdlib.h> #define BITS_2_WORDS(n) (((n)+31)>>5) int Bitsize2Wordsize(int nBits); Ipp32u* rand32(Ipp32u* pX, int size); IppsBigNumState* newBN(int len, const Ipp32u* pData=0); IppsBigNumState* newRandBN(int len); void deleteBN(IppsBigNumState* pBN); IppsPRNGState* newPRNG(int seedBitsize=160); void deletePRNG(IppsPRNGState* pPRNG); IppsPrimeState* newPrimeGen(int seedBitsize=160); void deletePrimeGen(IppsPrimeState* pPrime); IppsRSAState* newRSA(int lenN, int lenP, IppRSAKeyType type); void deleteRSA(IppsRSAState* pRSA); IppsDLPState* newDLP(int lenM, int lenL); void deleteDLP(IppsDLPState* pDLP); #endif // _CPOBJS_H_


C++ definitions of functions creating cryptographic contexts are given below. For the declarations to be included, see the preceding Declarations section.
#include "xsample_cpobjs.h" // convert bitsize into 32-bit wordsize int Bitsize2Wordsize(int nBits) { return (nBits+31)>>5; } // new BN number IppsBigNumState* newBN(int len, const Ipp32u* pData) { int size; ippsBigNumGetSize(len, &size); IppsBigNumState* pBN = (IppsBigNumState*)( new Ipp8u [size] ); ippsBigNumInit(len, pBN); if(pData) ippsSet_BN(IppsBigNumPOS, len, pData, pBN); return pBN; } void deleteBN(IppsBigNumState* pBN) { delete [] (Ipp8u*)pBN; } // set up array of 32-bit items random Ipp32u* rand32(Ipp32u* pX, int size) { for(int n=0; n<size; n++) pX[n] = (rand()<<16) + rand(); return pX; } IppsBigNumState* newRandBN(int len) { Ipp32u* pBuffer = new Ipp32u [len]; IppsBigNumState* pBN = newBN(len, rand32(pBuffer,len)); delete [] pBuffer; return pBN; } // // 'external' PRNG // IppsPRNGState* newPRNG(int seedBitsize) { int seedSize = Bitsize2Wordsize(seedBitsize); Ipp32u* seed = new Ipp32u [seedSize]; Ipp32u* augm = new Ipp32u [seedSize]; int size; IppsBigNumState* pTmp; ippsPRNGGetSize(&size); IppsPRNGState* pCtx = (IppsPRNGState*)( new Ipp8u [size] ); ippsPRNGInit(seedBitsize, pCtx); ippsPRNGSetSeed(pTmp=newBN(seedSize,rand32(seed,seedSize)), pCtx); delete [] (Ipp8u*)pTmp; ippsPRNGSetAugment(pTmp=newBN(seedSize,rand32(augm,seedSize)),pCtx); delete [] (Ipp8u*)pTmp; delete [] seed; delete [] augm; return pCtx; } void deletePRNG(IppsPRNGState* pPRNG) { delete [] (Ipp8u*)pPRNG; } // // Prime Generator context // IppsPrimeState* newPrimeGen(int maxBits) { int size; ippsPrimeGetSize(maxBits, &size); IppsPrimeState* pCtx = (IppsPrimeState*)( new Ipp8u [size] ); ippsPrimeInit(maxBits, pCtx); return pCtx; } void deletePrimeGen(IppsPrimeState* pPrimeG) { delete [] (Ipp8u*)pPrimeG; } // // RSA context // IppsRSAState* newRSA(int lenN, int lenP, IppRSAKeyType type) { int size; ippsRSAGetSize(lenN,lenP, type, &size); IppsRSAState* pCtx = (IppsRSAState*)( new Ipp8u [size] ); ippsRSAInit(lenN,lenP, type, pCtx); return pCtx; } void deleteRSA(IppsRSAState* pRSA) { delete [] (Ipp8u*)pRSA; } // // DLP context // IppsDLPState* newDLP(int lenM, int lenL) { int size; ippsDLPGetSize(lenM, lenL, &size); IppsDLPState *pCtx= (IppsDLPState *)new Ipp8u[ size ]; ippsDLPInit(lenM, lenL, pCtx); return pCtx; } void deleteDLP(IppsDLPState* pDLP) { delete [] (Ipp8u*)pDLP; }

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