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comparison s_ocb_done.c @ 143:5d99163f7e32 libtomcrypt-orig

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import of libtomcrypt 0.99
author Matt Johnston <matt@ucc.asn.au>
date Sun, 19 Dec 2004 11:34:45 +0000
parents 7faae8f46238
children
comparison
equal deleted inserted replaced
15:6362d3854bb4 143:5d99163f7e32
23 */ 23 */
24 int __ocb_done(ocb_state *ocb, const unsigned char *pt, unsigned long ptlen, 24 int __ocb_done(ocb_state *ocb, const unsigned char *pt, unsigned long ptlen,
25 unsigned char *ct, unsigned char *tag, unsigned long *taglen, int mode) 25 unsigned char *ct, unsigned char *tag, unsigned long *taglen, int mode)
26 26
27 { 27 {
28 unsigned char Z[MAXBLOCKSIZE], Y[MAXBLOCKSIZE], X[MAXBLOCKSIZE]; 28 unsigned char *Z, *Y, *X;
29 int err, x; 29 int err, x;
30 30
31 _ARGCHK(ocb != NULL); 31 _ARGCHK(ocb != NULL);
32 _ARGCHK(pt != NULL); 32 _ARGCHK(pt != NULL);
33 _ARGCHK(ct != NULL); 33 _ARGCHK(ct != NULL);
39 if (ocb->block_len != cipher_descriptor[ocb->cipher].block_length || 39 if (ocb->block_len != cipher_descriptor[ocb->cipher].block_length ||
40 (int)ptlen > ocb->block_len || (int)ptlen < 0) { 40 (int)ptlen > ocb->block_len || (int)ptlen < 0) {
41 return CRYPT_INVALID_ARG; 41 return CRYPT_INVALID_ARG;
42 } 42 }
43 43
44 /* allocate ram */
45 Z = XMALLOC(MAXBLOCKSIZE);
46 Y = XMALLOC(MAXBLOCKSIZE);
47 X = XMALLOC(MAXBLOCKSIZE);
48 if (X == NULL || Y == NULL || Z == NULL) {
49 if (X != NULL) {
50 XFREE(X);
51 }
52 if (Y != NULL) {
53 XFREE(Y);
54 }
55 if (Z != NULL) {
56 XFREE(Z);
57 }
58 return CRYPT_MEM;
59 }
60
44 /* compute X[m] = len(pt[m]) XOR Lr XOR Z[m] */ 61 /* compute X[m] = len(pt[m]) XOR Lr XOR Z[m] */
45 ocb_shift_xor(ocb, X); 62 ocb_shift_xor(ocb, X);
46 memcpy(Z, X, ocb->block_len); 63 XMEMCPY(Z, X, ocb->block_len);
47 64
48 X[ocb->block_len-1] ^= (ptlen*8)&255; 65 X[ocb->block_len-1] ^= (ptlen*8)&255;
49 X[ocb->block_len-2] ^= ((ptlen*8)>>8)&255; 66 X[ocb->block_len-2] ^= ((ptlen*8)>>8)&255;
50 for (x = 0; x < ocb->block_len; x++) { 67 for (x = 0; x < ocb->block_len; x++) {
51 X[x] ^= ocb->Lr[x]; 68 X[x] ^= ocb->Lr[x];
88 tag[x] = X[x]; 105 tag[x] = X[x];
89 } 106 }
90 *taglen = x; 107 *taglen = x;
91 108
92 #ifdef CLEAN_STACK 109 #ifdef CLEAN_STACK
93 zeromem(X, sizeof(X)); 110 zeromem(X, MAXBLOCKSIZE);
94 zeromem(Y, sizeof(Y)); 111 zeromem(Y, MAXBLOCKSIZE);
95 zeromem(Z, sizeof(Z)); 112 zeromem(Z, MAXBLOCKSIZE);
96 zeromem(ocb, sizeof(*ocb)); 113 zeromem(ocb, sizeof(*ocb));
97 #endif 114 #endif
115
116 XFREE(X);
117 XFREE(Y);
118 XFREE(Z);
119
98 return CRYPT_OK; 120 return CRYPT_OK;
99 } 121 }
100 122
101 #endif 123 #endif
102 124