1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis 2 * 3 * LibTomCrypt is a library that provides various cryptographic 4 * algorithms in a highly modular and flexible manner. 5 * 6 * The library is free for all purposes without any express 7 * guarantee it works. 8 * 9 * Tom St Denis, tomstdenis (at) gmail.com, http://libtomcrypt.com 10 */ 11 #include "tomcrypt.h" 12 13 /** 14 @file omac_memory.c 15 OMAC1 support, process a block of memory, Tom St Denis 16 */ 17 18 #ifdef LTC_OMAC 19 20 /** 21 OMAC a block of memory 22 @param cipher The index of the desired cipher 23 @param key The secret key 24 @param keylen The length of the secret key (octets) 25 @param in The data to send through OMAC 26 @param inlen The length of the data to send through OMAC (octets) 27 @param out [out] The destination of the authentication tag 28 @param outlen [in/out] The max size and resulting size of the authentication tag (octets) 29 @return CRYPT_OK if successful 30 */ 31 int omac_memory(int cipher, 32 const unsigned char *key, unsigned long keylen, 33 const unsigned char *in, unsigned long inlen, 34 unsigned char *out, unsigned long *outlen) 35 { 36 int err; 37 omac_state *omac; 38 39 LTC_ARGCHK(key != NULL); 40 LTC_ARGCHK(in != NULL); 41 LTC_ARGCHK(out != NULL); 42 LTC_ARGCHK(outlen != NULL); 43 44 /* is the cipher valid? */ 45 if ((err = cipher_is_valid(cipher)) != CRYPT_OK) { 46 return err; 47 } 48 49 /* Use accelerator if found */ 50 if (cipher_descriptor[cipher].omac_memory != NULL) { 51 return cipher_descriptor[cipher].omac_memory(key, keylen, in, inlen, out, outlen); 52 } 53 54 /* allocate ram for omac state */ 55 omac = XMALLOC(sizeof(omac_state)); 56 if (omac == NULL) { 57 return CRYPT_MEM; 58 } 59 60 /* omac process the message */ 61 if ((err = omac_init(omac, cipher, key, keylen)) != CRYPT_OK) { 62 goto LBL_ERR; 63 } 64 if ((err = omac_process(omac, in, inlen)) != CRYPT_OK) { 65 goto LBL_ERR; 66 } 67 if ((err = omac_done(omac, out, outlen)) != CRYPT_OK) { 68 goto LBL_ERR; 69 } 70 71 err = CRYPT_OK; 72 LBL_ERR: 73 #ifdef LTC_CLEAN_STACK 74 zeromem(omac, sizeof(omac_state)); 75 #endif 76 77 XFREE(omac); 78 return err; 79 } 80 81 #endif 82 83 /* $Source: /cvs/libtom/libtomcrypt/src/mac/omac/omac_memory.c,v $ */ 84 /* $Revision: 1.6 $ */ 85 /* $Date: 2006/11/08 23:01:06 $ */ 86
