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@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 */
omac_memory(int cipher,const unsigned char * key,unsigned long keylen,const unsigned char * in,unsigned long inlen,unsigned char * out,unsigned long * outlen)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