| /* 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 |
| */ |
| |
| /** |
| @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: 1.3 $ */ |
| /* $Date: 2005/05/05 14:35:58 $ */ |