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comparison libtomcrypt/src/encauth/eax/eax_init.c @ 1471:6dba84798cd5

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Update to libtomcrypt 1.18.1, merged with Dropbear changes
author Matt Johnston <matt@ucc.asn.au>
date Fri, 09 Feb 2018 21:44:05 +0800
parents f849a5ca2efc
children
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1470:8bba51a55704 1471:6dba84798cd5
3 * LibTomCrypt is a library that provides various cryptographic 3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner. 4 * algorithms in a highly modular and flexible manner.
5 * 5 *
6 * The library is free for all purposes without any express 6 * The library is free for all purposes without any express
7 * guarantee it works. 7 * guarantee it works.
8 *
9 * Tom St Denis, [email protected], http://libtom.org
10 */ 8 */
11 9
12 /** 10 /**
13 @file eax_init.c 11 @file eax_init.c
14 EAX implementation, initialized EAX state, by Tom St Denis 12 EAX implementation, initialized EAX state, by Tom St Denis
15 */ 13 */
16 #include "tomcrypt.h" 14 #include "tomcrypt.h"
17 15
18 #ifdef LTC_EAX_MODE 16 #ifdef LTC_EAX_MODE
19 17
20 /** 18 /**
21 Initialized an EAX state 19 Initialized an EAX state
22 @param eax [out] The EAX state to initialize 20 @param eax [out] The EAX state to initialize
23 @param cipher The index of the desired cipher 21 @param cipher The index of the desired cipher
24 @param key The secret key 22 @param key The secret key
25 @param keylen The length of the secret key (octets) 23 @param keylen The length of the secret key (octets)
27 @param noncelen The length of the nonce (octets) 25 @param noncelen The length of the nonce (octets)
28 @param header The header for the EAX state 26 @param header The header for the EAX state
29 @param headerlen The header length (octets) 27 @param headerlen The header length (octets)
30 @return CRYPT_OK if successful 28 @return CRYPT_OK if successful
31 */ 29 */
32 int eax_init(eax_state *eax, int cipher, 30 int eax_init(eax_state *eax, int cipher,
33 const unsigned char *key, unsigned long keylen, 31 const unsigned char *key, unsigned long keylen,
34 const unsigned char *nonce, unsigned long noncelen, 32 const unsigned char *nonce, unsigned long noncelen,
35 const unsigned char *header, unsigned long headerlen) 33 const unsigned char *header, unsigned long headerlen)
36 { 34 {
37 unsigned char *buf; 35 unsigned char *buf;
67 } 65 }
68 66
69 /* N = LTC_OMAC_0K(nonce) */ 67 /* N = LTC_OMAC_0K(nonce) */
70 zeromem(buf, MAXBLOCKSIZE); 68 zeromem(buf, MAXBLOCKSIZE);
71 if ((err = omac_init(omac, cipher, key, keylen)) != CRYPT_OK) { 69 if ((err = omac_init(omac, cipher, key, keylen)) != CRYPT_OK) {
72 goto LBL_ERR; 70 goto LBL_ERR;
73 } 71 }
74 72
75 /* omac the [0]_n */ 73 /* omac the [0]_n */
76 if ((err = omac_process(omac, buf, blklen)) != CRYPT_OK) { 74 if ((err = omac_process(omac, buf, blklen)) != CRYPT_OK) {
77 goto LBL_ERR; 75 goto LBL_ERR;
78 } 76 }
79 /* omac the nonce */ 77 /* omac the nonce */
80 if ((err = omac_process(omac, nonce, noncelen)) != CRYPT_OK) { 78 if ((err = omac_process(omac, nonce, noncelen)) != CRYPT_OK) {
81 goto LBL_ERR; 79 goto LBL_ERR;
82 } 80 }
83 /* store result */ 81 /* store result */
84 len = sizeof(eax->N); 82 len = sizeof(eax->N);
85 if ((err = omac_done(omac, eax->N, &len)) != CRYPT_OK) { 83 if ((err = omac_done(omac, eax->N, &len)) != CRYPT_OK) {
86 goto LBL_ERR; 84 goto LBL_ERR;
87 } 85 }
88 86
89 /* H = LTC_OMAC_1K(header) */ 87 /* H = LTC_OMAC_1K(header) */
90 zeromem(buf, MAXBLOCKSIZE); 88 zeromem(buf, MAXBLOCKSIZE);
91 buf[blklen - 1] = 1; 89 buf[blklen - 1] = 1;
92 90
93 if ((err = omac_init(&eax->headeromac, cipher, key, keylen)) != CRYPT_OK) { 91 if ((err = omac_init(&eax->headeromac, cipher, key, keylen)) != CRYPT_OK) {
94 goto LBL_ERR; 92 goto LBL_ERR;
95 } 93 }
96 94
97 /* omac the [1]_n */ 95 /* omac the [1]_n */
98 if ((err = omac_process(&eax->headeromac, buf, blklen)) != CRYPT_OK) { 96 if ((err = omac_process(&eax->headeromac, buf, blklen)) != CRYPT_OK) {
99 goto LBL_ERR; 97 goto LBL_ERR;
100 } 98 }
101 /* omac the header */ 99 /* omac the header */
102 if (headerlen != 0) { 100 if (headerlen != 0) {
103 if ((err = omac_process(&eax->headeromac, header, headerlen)) != CRYPT_OK) { 101 if ((err = omac_process(&eax->headeromac, header, headerlen)) != CRYPT_OK) {
104 goto LBL_ERR; 102 goto LBL_ERR;
105 } 103 }
106 } 104 }
107 105
108 /* note we don't finish the headeromac, this allows us to add more header later */ 106 /* note we don't finish the headeromac, this allows us to add more header later */
109 107
110 /* setup the CTR mode */ 108 /* setup the CTR mode */
111 if ((err = ctr_start(cipher, eax->N, key, keylen, 0, CTR_COUNTER_BIG_ENDIAN, &eax->ctr)) != CRYPT_OK) { 109 if ((err = ctr_start(cipher, eax->N, key, keylen, 0, CTR_COUNTER_BIG_ENDIAN, &eax->ctr)) != CRYPT_OK) {
112 goto LBL_ERR; 110 goto LBL_ERR;
113 } 111 }
114 112
115 /* setup the LTC_OMAC for the ciphertext */ 113 /* setup the LTC_OMAC for the ciphertext */
116 if ((err = omac_init(&eax->ctomac, cipher, key, keylen)) != CRYPT_OK) { 114 if ((err = omac_init(&eax->ctomac, cipher, key, keylen)) != CRYPT_OK) {
117 goto LBL_ERR; 115 goto LBL_ERR;
118 } 116 }
119 117
120 /* omac [2]_n */ 118 /* omac [2]_n */
121 zeromem(buf, MAXBLOCKSIZE); 119 zeromem(buf, MAXBLOCKSIZE);
122 buf[blklen-1] = 2; 120 buf[blklen-1] = 2;
123 if ((err = omac_process(&eax->ctomac, buf, blklen)) != CRYPT_OK) { 121 if ((err = omac_process(&eax->ctomac, buf, blklen)) != CRYPT_OK) {
124 goto LBL_ERR; 122 goto LBL_ERR;
125 } 123 }
126 124
127 err = CRYPT_OK; 125 err = CRYPT_OK;
128 LBL_ERR: 126 LBL_ERR:
129 #ifdef LTC_CLEAN_STACK 127 #ifdef LTC_CLEAN_STACK
135 XFREE(buf); 133 XFREE(buf);
136 134
137 return err; 135 return err;
138 } 136 }
139 137
140 #endif 138 #endif
141 139
142 /* $Source$ */ 140 /* ref: $Format:%D$ */
143 /* $Revision$ */ 141 /* git commit: $Format:%H$ */
144 /* $Date$ */ 142 /* commit time: $Format:%ai$ */