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//*****************************************************************************
//
//! Used to process(transform) blocks of data, either encrypt or decrypt it.
//!
//! \param ui32Base is the base address of the AES module.
//! \param pui32Src is a pointer to the memory location where the input data
//! is stored. The data must be padded to the 16-byte boundary.
//! \param pui32Dest is a pointer to the memory location output is written.
//! The space for written data must be rounded up to the 16-byte boundary.
//! \param ui32Length is the length of the cryptographic data in bytes.
//!
//! This function iterates the encryption or decryption mechanism number over
//! the data length. Before calling this function, ensure that the AES
//! module is properly configured the key, data size, mode, etc. Only ECB,
//! CBC, CTR, ICM, CFB, XTS and F8 operating modes should be used. The data
//! is processed in 4-word (16-byte) blocks.
//!
//! \note This function only supports values of \e ui32Length less than 2^32,
//! because the memory size is restricted to between 0 to 2^32 bytes.
//!
//! \return Returns true if data was processed successfully. Returns false
//! if data processing failed.
//
//*****************************************************************************
bool AESDataProcess(uint32_t ui32Base, uint32_t *pui32Src, uint32_t *pui32Dest, uint32_t ui32Length)
{
uint32_t ui32Count;
//
// Check the arguments.
//
ASSERT(ui32Base == AES_BASE);
//
// Write the length register first, which triggers the engine to start
// using this context.
//
AESLengthSet(AES_BASE, (uint64_t)ui32Length);
//
// Now loop until the blocks are written.
//
for(ui32Count = 0; ui32Count < ui32Length; ui32Count += 16) {//19
//
// Write the data registers.
//
AESDataWrite(ui32Base, pui32Src + (ui32Count / 4));
//
// Read the data registers.
//
AESDataRead(ui32Base, pui32Dest + (ui32Count / 4));
}
//
// Return true to indicate successful completion of the function.
//
return(true);
}
//*****************************************************************************
//
//! Used to set the write crypto data length in the AES module.
//!
//! \param ui32Base is the base address of the AES module.
//! \param ui64Length is the crypto data length in bytes.
//!
//! This function stores the cryptographic data length in blocks for all modes.
//! Data lengths up to (2^61 - 1) bytes are allowed. For GCM, any value up
//! to (2^36 - 2) bytes are allowed because a 32-bit block counter is used.
//! For basic modes (ECB/CBC/CTR/ICM/CFB128), zero can be programmed into the
//! length field, indicating that the length is infinite.
//!
//! When this function is called, the engine is triggered to start using
//! this context.
//!
//! \note This length does not include the authentication-only data used in
//! some modes. Use the AESAuthLengthSet() function to specify the
//! authentication data length.
//!
//! \return None
//
//*****************************************************************************
void AESLengthSet(uint32_t ui32Base, uint64_t ui64Length)
{
//
// Check the arguments.
//
ASSERT(ui32Base == AES_BASE);
//
// Write the length register by shifting the 64-bit ui64Length.
//
HWREG(ui32Base + AES_O_C_LENGTH_0) = (uint32_t)(ui64Length);
HWREG(ui32Base + AES_O_C_LENGTH_1) = (uint32_t)(ui64Length >> 32);
}
