Mercurial > dropbear

annotate libtomcrypt/src/modes/xts/xts_encrypt.c @ 1923:ffa0f666fde2

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Expand home path for MOTD file Patch modified by Matt Johnston Signed-off-by: Begley Brothers Inc <[email protected]>
author Begley Brothers Inc <begleybrothers@gmail.com>
date Thu, 09 Jul 2020 22:06:26 +1000
parents 6dba84798cd5
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 */
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 #include "tomcrypt.h"
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
11 /**
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
12 Source donated by Elliptic Semiconductor Inc (www.ellipticsemi.com) to the LibTom Projects
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
13 */
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 #ifdef LTC_XTS_MODE
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
17 static int _tweak_crypt(const unsigned char *P, unsigned char *C, unsigned char *T, symmetric_xts *xts)
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 unsigned long x;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 int err;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 /* tweak encrypt block i */
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 #ifdef LTC_FAST
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 for (x = 0; x < 16; x += sizeof(LTC_FAST_TYPE)) {
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
25 *(LTC_FAST_TYPE_PTR_CAST(&C[x])) = *(LTC_FAST_TYPE_PTR_CAST(&P[x])) ^ *(LTC_FAST_TYPE_PTR_CAST(&T[x]));
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 #else
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 for (x = 0; x < 16; x++) {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 C[x] = P[x] ^ T[x];
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 #endif
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
32
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 if ((err = cipher_descriptor[xts->cipher].ecb_encrypt(C, C, &xts->key1)) != CRYPT_OK) {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 return err;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 #ifdef LTC_FAST
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 for (x = 0; x < 16; x += sizeof(LTC_FAST_TYPE)) {
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
39 *(LTC_FAST_TYPE_PTR_CAST(&C[x])) ^= *(LTC_FAST_TYPE_PTR_CAST(&T[x]));
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 #else
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42 for (x = 0; x < 16; x++) {
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
43 C[x] = C[x] ^ T[x];
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 #endif
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47 /* LFSR the tweak */
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 xts_mult_x(T);
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 return CRYPT_OK;
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
51 }
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 /** XTS Encryption
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
54 @param pt [in] Plaintext
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
55 @param ptlen Length of plaintext (and ciphertext)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
56 @param ct [out] Ciphertext
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
57 @param tweak [in] The 128--bit encryption tweak (e.g. sector number)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
58 @param xts The XTS structure
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
59 Returns CRYPT_OK upon success
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
60 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
61 int xts_encrypt(const unsigned char *pt, unsigned long ptlen, unsigned char *ct, unsigned char *tweak,
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
62 symmetric_xts *xts)
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64 unsigned char PP[16], CC[16], T[16];
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65 unsigned long i, m, mo, lim;
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
66 int err;
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
67
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
68 /* check inputs */
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
69 LTC_ARGCHK(pt != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
70 LTC_ARGCHK(ct != NULL);
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
71 LTC_ARGCHK(tweak != NULL);
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
72 LTC_ARGCHK(xts != NULL);
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
73
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
74 /* check if valid */
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
75 if ((err = cipher_is_valid(xts->cipher)) != CRYPT_OK) {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
76 return err;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
77 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
78
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
79 /* get number of blocks */
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
80 m = ptlen >> 4;
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
81 mo = ptlen & 15;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
82
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
83 /* must have at least one full block */
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
84 if (m == 0) {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
85 return CRYPT_INVALID_ARG;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
86 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
87
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
88 if (mo == 0) {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
89 lim = m;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
90 } else {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
91 lim = m - 1;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
92 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
93
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
94 if (cipher_descriptor[xts->cipher].accel_xts_encrypt && lim > 0) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
95
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
96 /* use accelerated encryption for whole blocks */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
97 if ((err = cipher_descriptor[xts->cipher].accel_xts_encrypt(pt, ct, lim, tweak, &xts->key1, &xts->key2)) !=
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
98 CRYPT_OK) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
99 return err;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
100 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
101 ct += lim * 16;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
102 pt += lim * 16;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
103
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
104 /* tweak is encrypted on output */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
105 XMEMCPY(T, tweak, sizeof(T));
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
106 } else {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
107
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
108 /* encrypt the tweak */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
109 if ((err = cipher_descriptor[xts->cipher].ecb_encrypt(tweak, T, &xts->key2)) != CRYPT_OK) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
110 return err;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
111 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
112
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
113 for (i = 0; i < lim; i++) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
114 if ((err = _tweak_crypt(pt, ct, T, xts)) != CRYPT_OK) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
115 return err;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
116 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
117 ct += 16;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
118 pt += 16;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
119 }
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
120 }
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
121
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
122 /* if ptlen not divide 16 then */
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
123 if (mo > 0) {
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
124 /* CC = tweak encrypt block m-1 */
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
125 if ((err = _tweak_crypt(pt, CC, T, xts)) != CRYPT_OK) {
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
126 return err;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
127 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
128
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
129 /* Cm = first ptlen % 16 bytes of CC */
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
130 for (i = 0; i < mo; i++) {
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
131 PP[i] = pt[16 + i];
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
132 ct[16 + i] = CC[i];
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
133 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
134
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
135 for (; i < 16; i++) {
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
136 PP[i] = CC[i];
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
137 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
138
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
139 /* Cm-1 = Tweak encrypt PP */
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
140 if ((err = _tweak_crypt(PP, ct, T, xts)) != CRYPT_OK) {
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
141 return err;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
142 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
143 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
144
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
145 /* Decrypt the tweak back */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
146 if ((err = cipher_descriptor[xts->cipher].ecb_decrypt(T, tweak, &xts->key2)) != CRYPT_OK) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
147 return err;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
148 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
149
1435
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
150 return err;
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
151 }
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
152
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
153 #endif
f849a5ca2efc update to libtomcrypt 1.17 (with Dropbear changes)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
154
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
155 /* ref: $Format:%D$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
156 /* git commit: $Format:%H$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents: 1435
diff changeset
157 /* commit time: $Format:%ai$ */