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comparison libtomcrypt/src/ciphers/xtea.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 xtea.c 11 @file xtea.c
14 Implementation of LTC_XTEA, Tom St Denis 12 Implementation of LTC_XTEA, Tom St Denis
26 &xtea_ecb_encrypt, 24 &xtea_ecb_encrypt,
27 &xtea_ecb_decrypt, 25 &xtea_ecb_decrypt,
28 &xtea_test, 26 &xtea_test,
29 &xtea_done, 27 &xtea_done,
30 &xtea_keysize, 28 &xtea_keysize,
31 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL 29 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
32 }; 30 };
33 31
34 int xtea_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey) 32 int xtea_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
35 { 33 {
36 unsigned long x, sum, K[4]; 34 ulong32 x, sum, K[4];
37 35
38 LTC_ARGCHK(key != NULL); 36 LTC_ARGCHK(key != NULL);
39 LTC_ARGCHK(skey != NULL); 37 LTC_ARGCHK(skey != NULL);
40 38
41 /* check arguments */ 39 /* check arguments */
42 if (keylen != 16) { 40 if (keylen != 16) {
46 if (num_rounds != 0 && num_rounds != 32) { 44 if (num_rounds != 0 && num_rounds != 32) {
47 return CRYPT_INVALID_ROUNDS; 45 return CRYPT_INVALID_ROUNDS;
48 } 46 }
49 47
50 /* load key */ 48 /* load key */
51 LOAD32L(K[0], key+0); 49 LOAD32H(K[0], key+0);
52 LOAD32L(K[1], key+4); 50 LOAD32H(K[1], key+4);
53 LOAD32L(K[2], key+8); 51 LOAD32H(K[2], key+8);
54 LOAD32L(K[3], key+12); 52 LOAD32H(K[3], key+12);
55 53
56 for (x = sum = 0; x < 32; x++) { 54 for (x = sum = 0; x < 32; x++) {
57 skey->xtea.A[x] = (sum + K[sum&3]) & 0xFFFFFFFFUL; 55 skey->xtea.A[x] = (sum + K[sum&3]) & 0xFFFFFFFFUL;
58 sum = (sum + 0x9E3779B9UL) & 0xFFFFFFFFUL; 56 sum = (sum + 0x9E3779B9UL) & 0xFFFFFFFFUL;
59 skey->xtea.B[x] = (sum + K[(sum>>11)&3]) & 0xFFFFFFFFUL; 57 skey->xtea.B[x] = (sum + K[(sum>>11)&3]) & 0xFFFFFFFFUL;
60 } 58 }
61 59
62 #ifdef LTC_CLEAN_STACK 60 #ifdef LTC_CLEAN_STACK
63 zeromem(&K, sizeof(K)); 61 zeromem(&K, sizeof(K));
64 #endif 62 #endif
65 63
66 return CRYPT_OK; 64 return CRYPT_OK;
67 } 65 }
68 66
69 /** 67 /**
70 Encrypts a block of text with LTC_XTEA 68 Encrypts a block of text with LTC_XTEA
73 @param skey The key as scheduled 71 @param skey The key as scheduled
74 @return CRYPT_OK if successful 72 @return CRYPT_OK if successful
75 */ 73 */
76 int xtea_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey) 74 int xtea_ecb_encrypt(const unsigned char *pt, unsigned char *ct, symmetric_key *skey)
77 { 75 {
78 unsigned long y, z; 76 ulong32 y, z;
79 int r; 77 int r;
80 78
81 LTC_ARGCHK(pt != NULL); 79 LTC_ARGCHK(pt != NULL);
82 LTC_ARGCHK(ct != NULL); 80 LTC_ARGCHK(ct != NULL);
83 LTC_ARGCHK(skey != NULL); 81 LTC_ARGCHK(skey != NULL);
84 82
85 LOAD32L(y, &pt[0]); 83 LOAD32H(y, &pt[0]);
86 LOAD32L(z, &pt[4]); 84 LOAD32H(z, &pt[4]);
87 for (r = 0; r < 32; r += 4) { 85 for (r = 0; r < 32; r += 4) {
88 y = (y + ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r])) & 0xFFFFFFFFUL; 86 y = (y + ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r])) & 0xFFFFFFFFUL;
89 z = (z + ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r])) & 0xFFFFFFFFUL; 87 z = (z + ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r])) & 0xFFFFFFFFUL;
90 88
91 y = (y + ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r+1])) & 0xFFFFFFFFUL; 89 y = (y + ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r+1])) & 0xFFFFFFFFUL;
95 z = (z + ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r+2])) & 0xFFFFFFFFUL; 93 z = (z + ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r+2])) & 0xFFFFFFFFUL;
96 94
97 y = (y + ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r+3])) & 0xFFFFFFFFUL; 95 y = (y + ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r+3])) & 0xFFFFFFFFUL;
98 z = (z + ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r+3])) & 0xFFFFFFFFUL; 96 z = (z + ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r+3])) & 0xFFFFFFFFUL;
99 } 97 }
100 STORE32L(y, &ct[0]); 98 STORE32H(y, &ct[0]);
101 STORE32L(z, &ct[4]); 99 STORE32H(z, &ct[4]);
102 return CRYPT_OK; 100 return CRYPT_OK;
103 } 101 }
104 102
105 /** 103 /**
106 Decrypts a block of text with LTC_XTEA 104 Decrypts a block of text with LTC_XTEA
107 @param ct The input ciphertext (8 bytes) 105 @param ct The input ciphertext (8 bytes)
108 @param pt The output plaintext (8 bytes) 106 @param pt The output plaintext (8 bytes)
109 @param skey The key as scheduled 107 @param skey The key as scheduled
110 @return CRYPT_OK if successful 108 @return CRYPT_OK if successful
111 */ 109 */
112 int xtea_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey) 110 int xtea_ecb_decrypt(const unsigned char *ct, unsigned char *pt, symmetric_key *skey)
113 { 111 {
114 unsigned long y, z; 112 ulong32 y, z;
115 int r; 113 int r;
116 114
117 LTC_ARGCHK(pt != NULL); 115 LTC_ARGCHK(pt != NULL);
118 LTC_ARGCHK(ct != NULL); 116 LTC_ARGCHK(ct != NULL);
119 LTC_ARGCHK(skey != NULL); 117 LTC_ARGCHK(skey != NULL);
120 118
121 LOAD32L(y, &ct[0]); 119 LOAD32H(y, &ct[0]);
122 LOAD32L(z, &ct[4]); 120 LOAD32H(z, &ct[4]);
123 for (r = 31; r >= 0; r -= 4) { 121 for (r = 31; r >= 0; r -= 4) {
124 z = (z - ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r])) & 0xFFFFFFFFUL; 122 z = (z - ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r])) & 0xFFFFFFFFUL;
125 y = (y - ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r])) & 0xFFFFFFFFUL; 123 y = (y - ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r])) & 0xFFFFFFFFUL;
126 124
127 z = (z - ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r-1])) & 0xFFFFFFFFUL; 125 z = (z - ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r-1])) & 0xFFFFFFFFUL;
131 y = (y - ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r-2])) & 0xFFFFFFFFUL; 129 y = (y - ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r-2])) & 0xFFFFFFFFUL;
132 130
133 z = (z - ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r-3])) & 0xFFFFFFFFUL; 131 z = (z - ((((y<<4)^(y>>5)) + y) ^ skey->xtea.B[r-3])) & 0xFFFFFFFFUL;
134 y = (y - ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r-3])) & 0xFFFFFFFFUL; 132 y = (y - ((((z<<4)^(z>>5)) + z) ^ skey->xtea.A[r-3])) & 0xFFFFFFFFUL;
135 } 133 }
136 STORE32L(y, &pt[0]); 134 STORE32H(y, &pt[0]);
137 STORE32L(z, &pt[4]); 135 STORE32H(z, &pt[4]);
138 return CRYPT_OK; 136 return CRYPT_OK;
139 } 137 }
140 138
141 /** 139 /**
142 Performs a self-test of the LTC_XTEA block cipher 140 Performs a self-test of the LTC_XTEA block cipher
144 */ 142 */
145 int xtea_test(void) 143 int xtea_test(void)
146 { 144 {
147 #ifndef LTC_TEST 145 #ifndef LTC_TEST
148 return CRYPT_NOP; 146 return CRYPT_NOP;
149 #else 147 #else
150 static const unsigned char key[16] = 148 static const struct {
151 { 0x78, 0x56, 0x34, 0x12, 0xf0, 0xcd, 0xcb, 0x9a, 149 unsigned char key[16], pt[8], ct[8];
152 0x48, 0x37, 0x26, 0x15, 0xc0, 0xbf, 0xae, 0x9d }; 150 } tests[] = {
153 static const unsigned char pt[8] = 151 {
154 { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 }; 152 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
155 static const unsigned char ct[8] = 153 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
156 { 0x75, 0xd7, 0xc5, 0xbf, 0xcf, 0x58, 0xc9, 0x3f }; 154 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
155 { 0xde, 0xe9, 0xd4, 0xd8, 0xf7, 0x13, 0x1e, 0xd9 }
156 }, {
157 { 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02,
158 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x04 },
159 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
160 { 0xa5, 0x97, 0xab, 0x41, 0x76, 0x01, 0x4d, 0x72 }
161 }, {
162 { 0x00, 0x00, 0x00, 0x03, 0x00, 0x00, 0x00, 0x04,
163 0x00, 0x00, 0x00, 0x05, 0x00, 0x00, 0x00, 0x06 },
164 { 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x02 },
165 { 0xb1, 0xfd, 0x5d, 0xa9, 0xcc, 0x6d, 0xc9, 0xdc }
166 }, {
167 { 0x78, 0x69, 0x5a, 0x4b, 0x3c, 0x2d, 0x1e, 0x0f,
168 0xf0, 0xe1, 0xd2, 0xc3, 0xb4, 0xa5, 0x96, 0x87 },
169 { 0xf0, 0xe1, 0xd2, 0xc3, 0xb4, 0xa5, 0x96, 0x87 },
170 { 0x70, 0x4b, 0x31, 0x34, 0x47, 0x44, 0xdf, 0xab }
171 }, {
172 { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
173 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f },
174 { 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48 },
175 { 0x49, 0x7d, 0xf3, 0xd0, 0x72, 0x61, 0x2c, 0xb5 }
176 }, {
177 { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
178 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f },
179 { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
180 { 0xe7, 0x8f, 0x2d, 0x13, 0x74, 0x43, 0x41, 0xd8 }
181 }, {
182 { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
183 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f },
184 { 0x5a, 0x5b, 0x6e, 0x27, 0x89, 0x48, 0xd7, 0x7f },
185 { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 }
186 }, {
187 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
188 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
189 { 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48 },
190 { 0xa0, 0x39, 0x05, 0x89, 0xf8, 0xb8, 0xef, 0xa5 }
191 }, {
192 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
193 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
194 { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 },
195 { 0xed, 0x23, 0x37, 0x5a, 0x82, 0x1a, 0x8c, 0x2d }
196 }, {
197 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
198 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
199 { 0x70, 0xe1, 0x22, 0x5d, 0x6e, 0x4e, 0x76, 0x55 },
200 { 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41 }
201 }
202 };
157 unsigned char tmp[2][8]; 203 unsigned char tmp[2][8];
158 symmetric_key skey; 204 symmetric_key skey;
159 int err, y; 205 int i, err, y;
160 206 for (i = 0; i < (int)(sizeof(tests)/sizeof(tests[0])); i++) {
161 if ((err = xtea_setup(key, 16, 0, &skey)) != CRYPT_OK) { 207 zeromem(&skey, sizeof(skey));
162 return err; 208 if ((err = xtea_setup(tests[i].key, 16, 0, &skey)) != CRYPT_OK) {
163 } 209 return err;
164 xtea_ecb_encrypt(pt, tmp[0], &skey); 210 }
165 xtea_ecb_decrypt(tmp[0], tmp[1], &skey); 211 xtea_ecb_encrypt(tests[i].pt, tmp[0], &skey);
166 212 xtea_ecb_decrypt(tmp[0], tmp[1], &skey);
167 if (XMEMCMP(tmp[0], ct, 8) != 0 || XMEMCMP(tmp[1], pt, 8) != 0) { 213
168 return CRYPT_FAIL_TESTVECTOR; 214 if (compare_testvector(tmp[0], 8, tests[i].ct, 8, "XTEA Encrypt", i) != 0 ||
169 } 215 compare_testvector(tmp[1], 8, tests[i].pt, 8, "XTEA Decrypt", i) != 0) {
216 return CRYPT_FAIL_TESTVECTOR;
217 }
170 218
171 /* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */ 219 /* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */
172 for (y = 0; y < 8; y++) tmp[0][y] = 0; 220 for (y = 0; y < 8; y++) tmp[0][y] = 0;
173 for (y = 0; y < 1000; y++) xtea_ecb_encrypt(tmp[0], tmp[0], &skey); 221 for (y = 0; y < 1000; y++) xtea_ecb_encrypt(tmp[0], tmp[0], &skey);
174 for (y = 0; y < 1000; y++) xtea_ecb_decrypt(tmp[0], tmp[0], &skey); 222 for (y = 0; y < 1000; y++) xtea_ecb_decrypt(tmp[0], tmp[0], &skey);
175 for (y = 0; y < 8; y++) if (tmp[0][y] != 0) return CRYPT_FAIL_TESTVECTOR; 223 for (y = 0; y < 8; y++) if (tmp[0][y] != 0) return CRYPT_FAIL_TESTVECTOR;
224 } /* for */
176 225
177 return CRYPT_OK; 226 return CRYPT_OK;
178 #endif 227 #endif
179 } 228 }
180 229
181 /** Terminate the context 230 /** Terminate the context
182 @param skey The scheduled key 231 @param skey The scheduled key
183 */ 232 */
184 void xtea_done(symmetric_key *skey) 233 void xtea_done(symmetric_key *skey)
185 { 234 {
235 LTC_UNUSED_PARAM(skey);
186 } 236 }
187 237
188 /** 238 /**
189 Gets suitable key size 239 Gets suitable key size
190 @param keysize [in/out] The length of the recommended key (in bytes). This function will store the suitable size back in this variable. 240 @param keysize [in/out] The length of the recommended key (in bytes). This function will store the suitable size back in this variable.
192 */ 242 */
193 int xtea_keysize(int *keysize) 243 int xtea_keysize(int *keysize)
194 { 244 {
195 LTC_ARGCHK(keysize != NULL); 245 LTC_ARGCHK(keysize != NULL);
196 if (*keysize < 16) { 246 if (*keysize < 16) {
197 return CRYPT_INVALID_KEYSIZE; 247 return CRYPT_INVALID_KEYSIZE;
198 } 248 }
199 *keysize = 16; 249 *keysize = 16;
200 return CRYPT_OK; 250 return CRYPT_OK;
201 } 251 }
202 252
204 #endif 254 #endif
205 255
206 256
207 257
208 258
209 /* $Source$ */ 259 /* ref: $Format:%D$ */
210 /* $Revision$ */ 260 /* git commit: $Format:%H$ */
211 /* $Date$ */ 261 /* commit time: $Format:%ai$ */