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comparison src/encauth/gcm/gcm_init.c @ 209:39d5d58461d6 libtomcrypt-orig LTC_1.05

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Import of libtomcrypt 1.05
author Matt Johnston <matt@ucc.asn.au>
date Wed, 06 Jul 2005 03:53:40 +0000
parents 1c15b283127b
children
comparison
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191:1c15b283127b 209:39d5d58461d6
15 */ 15 */
16 #include "tomcrypt.h" 16 #include "tomcrypt.h"
17 17
18 #ifdef GCM_MODE 18 #ifdef GCM_MODE
19 19
20 #ifdef GCM_TABLES
21
22 /* this is x*2^128 mod p(x) ... the results are 16 bytes each stored in a packed format. Since only the
23 * lower 16 bits are not zero'ed I removed the upper 14 bytes */
24 static const unsigned char gcm_shift_table[256*2] = {
25 0x00, 0x00, 0x01, 0xc2, 0x03, 0x84, 0x02, 0x46, 0x07, 0x08, 0x06, 0xca, 0x04, 0x8c, 0x05, 0x4e,
26 0x0e, 0x10, 0x0f, 0xd2, 0x0d, 0x94, 0x0c, 0x56, 0x09, 0x18, 0x08, 0xda, 0x0a, 0x9c, 0x0b, 0x5e,
27 0x1c, 0x20, 0x1d, 0xe2, 0x1f, 0xa4, 0x1e, 0x66, 0x1b, 0x28, 0x1a, 0xea, 0x18, 0xac, 0x19, 0x6e,
28 0x12, 0x30, 0x13, 0xf2, 0x11, 0xb4, 0x10, 0x76, 0x15, 0x38, 0x14, 0xfa, 0x16, 0xbc, 0x17, 0x7e,
29 0x38, 0x40, 0x39, 0x82, 0x3b, 0xc4, 0x3a, 0x06, 0x3f, 0x48, 0x3e, 0x8a, 0x3c, 0xcc, 0x3d, 0x0e,
30 0x36, 0x50, 0x37, 0x92, 0x35, 0xd4, 0x34, 0x16, 0x31, 0x58, 0x30, 0x9a, 0x32, 0xdc, 0x33, 0x1e,
31 0x24, 0x60, 0x25, 0xa2, 0x27, 0xe4, 0x26, 0x26, 0x23, 0x68, 0x22, 0xaa, 0x20, 0xec, 0x21, 0x2e,
32 0x2a, 0x70, 0x2b, 0xb2, 0x29, 0xf4, 0x28, 0x36, 0x2d, 0x78, 0x2c, 0xba, 0x2e, 0xfc, 0x2f, 0x3e,
33 0x70, 0x80, 0x71, 0x42, 0x73, 0x04, 0x72, 0xc6, 0x77, 0x88, 0x76, 0x4a, 0x74, 0x0c, 0x75, 0xce,
34 0x7e, 0x90, 0x7f, 0x52, 0x7d, 0x14, 0x7c, 0xd6, 0x79, 0x98, 0x78, 0x5a, 0x7a, 0x1c, 0x7b, 0xde,
35 0x6c, 0xa0, 0x6d, 0x62, 0x6f, 0x24, 0x6e, 0xe6, 0x6b, 0xa8, 0x6a, 0x6a, 0x68, 0x2c, 0x69, 0xee,
36 0x62, 0xb0, 0x63, 0x72, 0x61, 0x34, 0x60, 0xf6, 0x65, 0xb8, 0x64, 0x7a, 0x66, 0x3c, 0x67, 0xfe,
37 0x48, 0xc0, 0x49, 0x02, 0x4b, 0x44, 0x4a, 0x86, 0x4f, 0xc8, 0x4e, 0x0a, 0x4c, 0x4c, 0x4d, 0x8e,
38 0x46, 0xd0, 0x47, 0x12, 0x45, 0x54, 0x44, 0x96, 0x41, 0xd8, 0x40, 0x1a, 0x42, 0x5c, 0x43, 0x9e,
39 0x54, 0xe0, 0x55, 0x22, 0x57, 0x64, 0x56, 0xa6, 0x53, 0xe8, 0x52, 0x2a, 0x50, 0x6c, 0x51, 0xae,
40 0x5a, 0xf0, 0x5b, 0x32, 0x59, 0x74, 0x58, 0xb6, 0x5d, 0xf8, 0x5c, 0x3a, 0x5e, 0x7c, 0x5f, 0xbe,
41 0xe1, 0x00, 0xe0, 0xc2, 0xe2, 0x84, 0xe3, 0x46, 0xe6, 0x08, 0xe7, 0xca, 0xe5, 0x8c, 0xe4, 0x4e,
42 0xef, 0x10, 0xee, 0xd2, 0xec, 0x94, 0xed, 0x56, 0xe8, 0x18, 0xe9, 0xda, 0xeb, 0x9c, 0xea, 0x5e,
43 0xfd, 0x20, 0xfc, 0xe2, 0xfe, 0xa4, 0xff, 0x66, 0xfa, 0x28, 0xfb, 0xea, 0xf9, 0xac, 0xf8, 0x6e,
44 0xf3, 0x30, 0xf2, 0xf2, 0xf0, 0xb4, 0xf1, 0x76, 0xf4, 0x38, 0xf5, 0xfa, 0xf7, 0xbc, 0xf6, 0x7e,
45 0xd9, 0x40, 0xd8, 0x82, 0xda, 0xc4, 0xdb, 0x06, 0xde, 0x48, 0xdf, 0x8a, 0xdd, 0xcc, 0xdc, 0x0e,
46 0xd7, 0x50, 0xd6, 0x92, 0xd4, 0xd4, 0xd5, 0x16, 0xd0, 0x58, 0xd1, 0x9a, 0xd3, 0xdc, 0xd2, 0x1e,
47 0xc5, 0x60, 0xc4, 0xa2, 0xc6, 0xe4, 0xc7, 0x26, 0xc2, 0x68, 0xc3, 0xaa, 0xc1, 0xec, 0xc0, 0x2e,
48 0xcb, 0x70, 0xca, 0xb2, 0xc8, 0xf4, 0xc9, 0x36, 0xcc, 0x78, 0xcd, 0xba, 0xcf, 0xfc, 0xce, 0x3e,
49 0x91, 0x80, 0x90, 0x42, 0x92, 0x04, 0x93, 0xc6, 0x96, 0x88, 0x97, 0x4a, 0x95, 0x0c, 0x94, 0xce,
50 0x9f, 0x90, 0x9e, 0x52, 0x9c, 0x14, 0x9d, 0xd6, 0x98, 0x98, 0x99, 0x5a, 0x9b, 0x1c, 0x9a, 0xde,
51 0x8d, 0xa0, 0x8c, 0x62, 0x8e, 0x24, 0x8f, 0xe6, 0x8a, 0xa8, 0x8b, 0x6a, 0x89, 0x2c, 0x88, 0xee,
52 0x83, 0xb0, 0x82, 0x72, 0x80, 0x34, 0x81, 0xf6, 0x84, 0xb8, 0x85, 0x7a, 0x87, 0x3c, 0x86, 0xfe,
53 0xa9, 0xc0, 0xa8, 0x02, 0xaa, 0x44, 0xab, 0x86, 0xae, 0xc8, 0xaf, 0x0a, 0xad, 0x4c, 0xac, 0x8e,
54 0xa7, 0xd0, 0xa6, 0x12, 0xa4, 0x54, 0xa5, 0x96, 0xa0, 0xd8, 0xa1, 0x1a, 0xa3, 0x5c, 0xa2, 0x9e,
55 0xb5, 0xe0, 0xb4, 0x22, 0xb6, 0x64, 0xb7, 0xa6, 0xb2, 0xe8, 0xb3, 0x2a, 0xb1, 0x6c, 0xb0, 0xae,
56 0xbb, 0xf0, 0xba, 0x32, 0xb8, 0x74, 0xb9, 0xb6, 0xbc, 0xf8, 0xbd, 0x3a, 0xbf, 0x7c, 0xbe, 0xbe };
57
58 #endif
59
20 /** 60 /**
21 Initialize a GCM state 61 Initialize a GCM state
22 @param gcm The GCM state to initialize 62 @param gcm The GCM state to initialize
23 @param cipher The index of the cipher to use 63 @param cipher The index of the cipher to use
24 @param key The secret key 64 @param key The secret key
29 const unsigned char *key, int keylen) 69 const unsigned char *key, int keylen)
30 { 70 {
31 int err; 71 int err;
32 unsigned char B[16]; 72 unsigned char B[16];
33 #ifdef GCM_TABLES 73 #ifdef GCM_TABLES
34 int x, y; 74 int x, y, z, t;
35 #endif 75 #endif
36 76
37 LTC_ARGCHK(gcm != NULL); 77 LTC_ARGCHK(gcm != NULL);
38 LTC_ARGCHK(key != NULL); 78 LTC_ARGCHK(key != NULL);
39 79
70 gcm->totlen = 0; 110 gcm->totlen = 0;
71 gcm->pttotlen = 0; 111 gcm->pttotlen = 0;
72 112
73 #ifdef GCM_TABLES 113 #ifdef GCM_TABLES
74 /* setup tables */ 114 /* setup tables */
115
116 /* generate the first table as it has no shifting (from which we make the other tables) */
75 zeromem(B, 16); 117 zeromem(B, 16);
76 for (x = 0; x < 16; x++) { 118 for (y = 0; y < 256; y++) {
77 for (y = 0; y < 256; y++) { 119 B[0] = y;
78 B[x] = y; 120 gcm_gf_mult(gcm->H, B, &gcm->PC[0][y][0]);
79 gcm_gf_mult(gcm->H, B, &gcm->PC[x][y][0]);
80 }
81 B[x] = 0;
82 } 121 }
122
123 /* now generate the rest of the tables based the previous table */
124 for (x = 1; x < 16; x++) {
125 for (y = 0; y < 256; y++) {
126 /* now shift it right by 8 bits */
127 t = gcm->PC[x-1][y][15];
128 for (z = 15; z > 0; z--) {
129 gcm->PC[x][y][z] = gcm->PC[x-1][y][z-1];
130 }
131 gcm->PC[x][y][0] = gcm_shift_table[t<<1];
132 gcm->PC[x][y][1] ^= gcm_shift_table[(t<<1)+1];
133 }
134 }
135
83 #endif 136 #endif
84 137
85 return CRYPT_OK; 138 return CRYPT_OK;
86 } 139 }
87 140
88 #endif 141 #endif
142
143 /* $Source: /cvs/libtom/libtomcrypt/src/encauth/gcm/gcm_init.c,v $ */
144 /* $Revision: 1.15 $ */
145 /* $Date: 2005/05/21 15:05:19 $ */