/* 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 *//**   @file ocb_encrypt_authenticate_memory.c  OCB implementation, encrypt block of memory, by Tom St Denis*/#include "tomcrypt.h"#ifdef OCB_MODE/**   Encrypt and generate an authentication code for a buffer of memory   @param cipher     The index of the cipher desired   @param key        The secret key   @param keylen     The length of the secret key (octets)   @param nonce      The session nonce (length of the block ciphers block size)   @param pt         The plaintext   @param ptlen      The length of the plaintext (octets)   @param ct         [out] The ciphertext   @param tag        [out] The authentication tag   @param taglen     [in/out] The max size and resulting size of the authentication tag   @return CRYPT_OK if successful*/int ocb_encrypt_authenticate_memory(int cipher,    const unsigned char *key,    unsigned long keylen,    const unsigned char *nonce,      const unsigned char *pt,     unsigned long ptlen,          unsigned char *ct,          unsigned char *tag,    unsigned long *taglen){   int err;   ocb_state *ocb;   LTC_ARGCHK(key    != NULL);   LTC_ARGCHK(nonce  != NULL);   LTC_ARGCHK(pt     != NULL);   LTC_ARGCHK(ct     != NULL);   LTC_ARGCHK(tag    != NULL);   LTC_ARGCHK(taglen != NULL);   /* allocate ram */   ocb = XMALLOC(sizeof(ocb_state));   if (ocb == NULL) {      return CRYPT_MEM;   }   if ((err = ocb_init(ocb, cipher, key, keylen, nonce)) != CRYPT_OK) {      goto LBL_ERR;   }   while (ptlen > (unsigned long)ocb->block_len) {        if ((err = ocb_encrypt(ocb, pt, ct)) != CRYPT_OK) {           goto LBL_ERR;        }        ptlen   -= ocb->block_len;        pt      += ocb->block_len;        ct      += ocb->block_len;   }   err = ocb_done_encrypt(ocb, pt, ptlen, ct, tag, taglen);LBL_ERR:#ifdef LTC_CLEAN_STACK   zeromem(ocb, sizeof(ocb_state));#endif   XFREE(ocb);   return err;}#endif/* $Source: /cvs/libtom/libtomcrypt/src/encauth/ocb/ocb_encrypt_authenticate_memory.c,v $ *//* $Revision: 1.4 $ *//* $Date: 2006/03/31 14:15:35 $ */