/******************************************************************************/
/* LICENSE:                                                                   */
/* This submission to NSS is to be made available under the terms of the      */
/* Mozilla Public License, v. 2.0. You can obtain one at http:                */
/* //mozilla.org/MPL/2.0/.                                                    */
/******************************************************************************/
/* Copyright(c) 2013, Intel Corp.                                             */
/******************************************************************************/
/* Reference:                                                                 */
/* [1] Shay Gueron, Michael E. Kounavis: Intel® Carry-Less Multiplication     */
/*     Instruction and its Usage for Computing the GCM Mode (Rev. 2.01)       */
/*     http://software.intel.com/sites/default/files/article/165685/clmul-wp-r*/
/*ev-2.01-2012-09-21.pdf                                                      */
/* [2] S. Gueron, M. E. Kounavis: Efficient Implementation of the Galois      */
/*     Counter Mode Using a Carry-less Multiplier and a Fast Reduction        */
/*     Algorithm. Information Processing Letters 110: 549–553 (2010).         */
/* [3] S. Gueron: AES Performance on the 2nd Generation Intel® Core™ Processor*/
/*     Family (to be posted) (2012).                                          */
/* [4] S. Gueron: Fast GHASH computations for speeding up AES-GCM (to be      */
/*     published) (2012).                                                     */

#ifndef INTEL_GCM_H
#define INTEL_GCM_H 1

#include "blapii.h"

typedef struct intel_AES_GCMContextStr intel_AES_GCMContext;

intel_AES_GCMContext *intel_AES_GCM_CreateContext(void *context, freeblCipherFunc cipher,
			const unsigned char *params, unsigned int blocksize);

void intel_AES_GCM_DestroyContext(intel_AES_GCMContext *gcm, PRBool freeit);

SECStatus intel_AES_GCM_EncryptUpdate(intel_AES_GCMContext  *gcm, unsigned char *outbuf,
			unsigned int *outlen, unsigned int maxout,
			const unsigned char *inbuf, unsigned int inlen,
			unsigned int blocksize);

SECStatus intel_AES_GCM_DecryptUpdate(intel_AES_GCMContext *gcm, unsigned char *outbuf,
			unsigned int *outlen, unsigned int maxout,
			const unsigned char *inbuf, unsigned int inlen,
			unsigned int blocksize);

/* Prorotypes of functions in the assembler file for fast AES-GCM, using 
   Intel AES-NI and CLMUL-NI, as described in [1]
   [1] Shay Gueron, Michael E. Kounavis: Intel® Carry-Less Multiplication 
       Instruction and its Usage for Computing the GCM Mode                */
       
/* Prepares the constants used in the aggregated reduction method */
void intel_aes_gcmINIT(unsigned char Htbl[16*16],
                       unsigned char *KS,
                       int NR);

/* Produces the final GHASH value */
void intel_aes_gcmTAG(unsigned char Htbl[16*16], 
                      unsigned char *Tp, 
                      unsigned long Mlen, 
                      unsigned long Alen, 
                      unsigned char* X0, 
                      unsigned char* TAG);

/* Hashes the Additional Authenticated Data, should be used before enc/dec.
   Operates on whole blocks only. Partial blocks should be padded externally. */
void intel_aes_gcmAAD(unsigned char Htbl[16*16], 
                      unsigned char *AAD, 
                      unsigned long Alen, 
                      unsigned char *Tp);

/* Encrypts and hashes the Plaintext. 
   Operates on any length of data, however partial block should only be encrypted
   at the last call, otherwise the result will be incorrect. */
void intel_aes_gcmENC(const unsigned char* PT, 
                      unsigned char* CT, 
                      void *Gctx, 
                      unsigned long len);
                  
/* Similar to ENC, but decrypts the Ciphertext. */
void intel_aes_gcmDEC(const unsigned char* CT, 
                      unsigned char* PT, 
                      void *Gctx, 
                      unsigned long len);

#endif