1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis */
2 /* SPDX-License-Identifier: Unlicense */
3
4 /**
5 @file eax_encrypt_authenticate_memory.c
6 EAX implementation, encrypt a block of memory, by Tom St Denis
7 */
8 #include "tomcrypt_private.h"
9
10 #ifdef LTC_EAX_MODE
11
12 /**
13 EAX encrypt and produce an authentication tag
14 @param cipher The index of the cipher desired
15 @param key The secret key to use
16 @param keylen The length of the secret key (octets)
17 @param nonce The session nonce [use once]
18 @param noncelen The length of the nonce
19 @param header The header for the session
20 @param headerlen The length of the header (octets)
21 @param pt The plaintext
22 @param ptlen The length of the plaintext (octets)
23 @param ct [out] The ciphertext
24 @param tag [out] The destination tag
25 @param taglen [in/out] The max size and resulting size of the authentication tag
26 @return CRYPT_OK if successful
27 */
eax_encrypt_authenticate_memory(int cipher,const unsigned char * key,unsigned long keylen,const unsigned char * nonce,unsigned long noncelen,const unsigned char * header,unsigned long headerlen,const unsigned char * pt,unsigned long ptlen,unsigned char * ct,unsigned char * tag,unsigned long * taglen)28 int eax_encrypt_authenticate_memory(int cipher,
29 const unsigned char *key, unsigned long keylen,
30 const unsigned char *nonce, unsigned long noncelen,
31 const unsigned char *header, unsigned long headerlen,
32 const unsigned char *pt, unsigned long ptlen,
33 unsigned char *ct,
34 unsigned char *tag, unsigned long *taglen)
35 {
36 int err;
37 eax_state *eax;
38
39 LTC_ARGCHK(key != NULL);
40 LTC_ARGCHK(pt != NULL);
41 LTC_ARGCHK(ct != NULL);
42 LTC_ARGCHK(tag != NULL);
43 LTC_ARGCHK(taglen != NULL);
44
45 eax = XMALLOC(sizeof(*eax));
46
47 if ((err = eax_init(eax, cipher, key, keylen, nonce, noncelen, header, headerlen)) != CRYPT_OK) {
48 goto LBL_ERR;
49 }
50
51 if ((err = eax_encrypt(eax, pt, ct, ptlen)) != CRYPT_OK) {
52 goto LBL_ERR;
53 }
54
55 if ((err = eax_done(eax, tag, taglen)) != CRYPT_OK) {
56 goto LBL_ERR;
57 }
58
59 err = CRYPT_OK;
60 LBL_ERR:
61 #ifdef LTC_CLEAN_STACK
62 zeromem(eax, sizeof(*eax));
63 #endif
64
65 XFREE(eax);
66
67 return err;
68 }
69
70 #endif
71