How to implement software AES-CTR in nRF52832 + S132 v2.0 + SDK11?

Question

Changhai Liao · Accepted Answer

Thank you for your reply. 
 I finished it a few days ago. 
 Maybe the code is not perfect. 
 uint8_t AESCTR_Encrypt(uint8_t *pPlain, uint16_t usPLen, uint8_t *pEncrypted, uint16_t usELen, uint16_t *pEValidLen,
 uint8_t *aIv, uint8_t *aKey)
{
 if (usELen < usPLen)
 {
 return (uint8_t)-1;
 }
 (void)nrf_ecb_init();
 nrf_ecb_set_key(aKey);
 uint8_t aIvOri[AESCTR_IV_LEN] = {0};
 uint8_t aIvEcb[AESCTR_IV_LEN] = {0};
 memcpy(aIvOri, aIv, AESCTR_IV_LEN);
 (void)nrf_ecb_crypt(aIvEcb, aIvOri);

 for (uint16_t usI = 0; usI < usPLen; usI++)
 {
 pEncrypted[usI] = pPlain[usI] ^ aIvEcb[usI & 0x0F];
 if ((usI & 0x0F) == 0x0F)
 {
 for (uint8_t ucJ = AESCTR_IV_LEN - 1; ucJ > 0; ucJ--)
 {
 if (++aIvOri[ucJ] != 0)
 {
 break;
 }
 }
 (void)nrf_ecb_crypt(aIvEcb, aIvOri);
 }
 }
 *pEValidLen = usPLen;
 return 0;
}

How to implement software AES-CTR in nRF52832 + S132 v2.0 + SDK11?

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