/* LibTomCrypt, modular cryptographic library -- Tom St Denis * * LibTomCrypt is a library that provides various cryptographic * algorithms in a highly modular and flexible manner. * * The library is free for all purposes without any express * guarantee it works. * * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com */#include "tomcrypt.h"/**    @file pmac_process.c   PMAC implementation, process data, by Tom St Denis */#ifdef PMAC/**  Process data in a PMAC stream  @param pmac     The PMAC state  @param in       The data to send through PMAC  @param inlen    The length of the data to send through PMAC  @return CRYPT_OK if successful*/int pmac_process(pmac_state *pmac, const unsigned char *in, unsigned long inlen){   int err, n;   unsigned long x;   unsigned char Z[MAXBLOCKSIZE];   LTC_ARGCHK(pmac != NULL);   LTC_ARGCHK(in   != NULL);   if ((err = cipher_is_valid(pmac->cipher_idx)) != CRYPT_OK) {      return err;   }   if ((pmac->buflen > (int)sizeof(pmac->block)) || (pmac->buflen < 0) ||       (pmac->block_len > (int)sizeof(pmac->block)) || (pmac->buflen > pmac->block_len)) {      return CRYPT_INVALID_ARG;   }#ifdef LTC_FAST   if (pmac->buflen == 0 && inlen > 16) {      unsigned long y;      for (x = 0; x < (inlen - 16); x += 16) {          pmac_shift_xor(pmac);          for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) {              *((LTC_FAST_TYPE*)(&Z[y])) = *((LTC_FAST_TYPE*)(&in[y])) ^ *((LTC_FAST_TYPE*)(&pmac->Li[y]));          }          if ((err = cipher_descriptor[pmac->cipher_idx].ecb_encrypt(Z, Z, &pmac->key)) != CRYPT_OK) {             return err;          }          for (y = 0; y < 16; y += sizeof(LTC_FAST_TYPE)) {              *((LTC_FAST_TYPE*)(&pmac->checksum[y])) ^= *((LTC_FAST_TYPE*)(&Z[y]));          }          in += 16;      }      inlen -= x;   }#endif   while (inlen != 0) {        /* ok if the block is full we xor in prev, encrypt and replace prev */       if (pmac->buflen == pmac->block_len) {          pmac_shift_xor(pmac);          for (x = 0; x < (unsigned long)pmac->block_len; x++) {               Z[x] = pmac->Li[x] ^ pmac->block[x];          }          if ((err = cipher_descriptor[pmac->cipher_idx].ecb_encrypt(Z, Z, &pmac->key)) != CRYPT_OK) {             return err;           }          for (x = 0; x < (unsigned long)pmac->block_len; x++) {              pmac->checksum[x] ^= Z[x];          }          pmac->buflen = 0;       }       /* add bytes */       n = MIN(inlen, (unsigned long)(pmac->block_len - pmac->buflen));       XMEMCPY(pmac->block + pmac->buflen, in, n);       pmac->buflen  += n;       inlen         -= n;       in            += n;   }#ifdef LTC_CLEAN_STACK   zeromem(Z, sizeof(Z));#endif   return CRYPT_OK;}#endif/* $Source: /cvs/libtom/libtomcrypt/src/mac/pmac/pmac_process.c,v $ *//* $Revision: 1.7 $ *//* $Date: 2006/03/31 14:15:35 $ */