/* 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.org */#include "tomcrypt.h"/**   @file omac_file.c  OMAC1 support, process a file, Tom St Denis*/#ifdef OMAC/**   OMAC a file   @param cipher   The index of the cipher desired   @param key      The secret key   @param keylen   The length of the secret key (octets)   @param filename The name of the file you wish to OMAC   @param out      [out] Where the authentication tag is to be stored   @param outlen   [in/out] The max size and resulting size of the authentication tag   @return CRYPT_OK if successful, CRYPT_NOP if file support has been disabled*/int omac_file(int cipher,               const unsigned char *key, unsigned long keylen,              const char *filename,                     unsigned char *out, unsigned long *outlen){#ifdef LTC_NO_FILE   return CRYPT_NOP;#else   int err, x;   omac_state omac;   FILE *in;   unsigned char buf[512];   LTC_ARGCHK(key      != NULL);   LTC_ARGCHK(filename != NULL);   LTC_ARGCHK(out      != NULL);   LTC_ARGCHK(outlen   != NULL);   in = fopen(filename, "rb");   if (in == NULL) {      return CRYPT_FILE_NOTFOUND;   }   if ((err = omac_init(&omac, cipher, key, keylen)) != CRYPT_OK) {      fclose(in);      return err;   }   do {      x = fread(buf, 1, sizeof(buf), in);      if ((err = omac_process(&omac, buf, x)) != CRYPT_OK) {         fclose(in);         return err;      }   } while (x == sizeof(buf));   fclose(in);   if ((err = omac_done(&omac, out, outlen)) != CRYPT_OK) {      return err;   }#ifdef LTC_CLEAN_STACK   zeromem(buf, sizeof(buf));#endif   return CRYPT_OK;#endif}#endif/* $Source: /cvs/libtom/libtomcrypt/src/mac/omac/omac_file.c,v $ *//* $Revision: 1.3 $ *//* $Date: 2005/05/05 14:35:58 $ */