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Example of Using TDES Functions

TDES Encryption and Decryption 
// Use of the ECB mode void TDES_sample(void){ // size of the TDES algorithm block is equal to 8 const int tdesBlkSize = 8; // get size of the context needed for the encryption/decryption operation int ctxSize; ippsDESGetSize(&ctxSize); // and allocate one IppsDESSpec* pCtx1 = (IppsDESSpec*)( new Ipp8u [ctxSize] ); IppsDESSpec* pCtx2 = (IppsDESSpec*)( new Ipp8u [ctxSize] ); IppsDESSpec* pCtx3 = (IppsDESSpec*)( new Ipp8u [ctxSize] ); // define the key Ipp8u key1[] = {0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08}; Ipp8u key2[] = {0x11,0x12,0x13,0x14,0x15,0x16,0x17,0x18}; Ipp8u key3[] = {0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28}; Ipp8u keyX[] = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}; // and prepare the context for the TDES usage ippsDESInit(key1, pCtx1); ippsDESInit(key2, pCtx2); ippsDESInit(key3, pCtx3); // define the message to be encrypted Ipp8u ptext[] = {"the quick brown fox jumps over the lazy dog"}; // allocate enough memory for the ciphertext // note that // the size of ciphertext is always a multiple of the cipher block size Ipp8u ctext[(sizeof(ptext)+desBlkSize-1) &~(desBlkSize-1)]; // encrypt (ECB mode) ptext message // pay attention to the 'length' parameter // it defines the number of bytes to be encrypted ippsTDESEncryptECB(ptext, ctext, sizeof(ctext), pCtx1, pCtx2, pCtx3, IppsCPPaddingNONE); // allocate memory for the decrypted message Ipp8u rtext[sizeof(ctext)]; // decrypt (ECB mode) ctext message // pay attention to the 'length' parameter // it defines the number of bytes to be decrypted ippsTDESDecryptECB(ctext, rtext, sizeof(ctext), pCtx1, pCtx2, pCtx3, IppsCPPaddingNONE); // remove actual secret from contexts ippsDESInit(keyX, pCtx1); ippsDESInit(keyX, pCtx2); ippsDESInit(keyX, pCtx3); // release resources delete (Ipp8u*)pCtx1; delete (Ipp8u*)pCtx2; delete (Ipp8u*)pCtx3; }

Product and Performance Information

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Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.