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comparison yarrow.c @ 0:d7da3b1e1540 libtomcrypt

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put back the 0.95 makefile which was inadvertently merged over
author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:21:40 +0000
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children 6362d3854bb4
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-1:000000000000 0:d7da3b1e1540
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
2 *
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
5 *
6 * The library is free for all purposes without any express
7 * guarantee it works.
8 *
9 * Tom St Denis, [email protected], http://libtomcrypt.org
10 */
11
12 #include "mycrypt.h"
13
14 #ifdef YARROW
15
16 const struct _prng_descriptor yarrow_desc =
17 {
18 "yarrow",
19 &yarrow_start,
20 &yarrow_add_entropy,
21 &yarrow_ready,
22 &yarrow_read
23 };
24
25 int yarrow_start(prng_state *prng)
26 {
27 int err;
28
29 _ARGCHK(prng != NULL);
30
31 /* these are the default hash/cipher combo used */
32 #ifdef RIJNDAEL
33 prng->yarrow.cipher = register_cipher(&rijndael_desc);
34 #elif defined(BLOWFISH)
35 prng->yarrow.cipher = register_cipher(&blowfish_desc);
36 #elif defined(TWOFISH)
37 prng->yarrow.cipher = register_cipher(&twofish_desc);
38 #elif defined(RC6)
39 prng->yarrow.cipher = register_cipher(&rc6_desc);
40 #elif defined(RC5)
41 prng->yarrow.cipher = register_cipher(&rc5_desc);
42 #elif defined(SAFERP)
43 prng->yarrow.cipher = register_cipher(&saferp_desc);
44 #elif defined(RC2)
45 prng->yarrow.cipher = register_cipher(&rc2_desc);
46 #elif defined(NOEKEON)
47 prng->yarrow.cipher = register_cipher(&noekeon_desc);
48 #elif defined(CAST5)
49 prng->yarrow.cipher = register_cipher(&cast5_desc);
50 #elif defined(XTEA)
51 prng->yarrow.cipher = register_cipher(&xtea_desc);
52 #elif defined(SAFER)
53 prng->yarrow.cipher = register_cipher(&safer_sk128_desc);
54 #elif defined(DES)
55 prng->yarrow.cipher = register_cipher(&des3_desc);
56 #elif
57 #error YARROW needs at least one CIPHER
58 #endif
59 if ((err = cipher_is_valid(prng->yarrow.cipher)) != CRYPT_OK) {
60 return err;
61 }
62
63 #ifdef SHA256
64 prng->yarrow.hash = register_hash(&sha256_desc);
65 #elif defined(SHA512)
66 prng->yarrow.hash = register_hash(&sha512_desc);
67 #elif defined(TIGER)
68 prng->yarrow.hash = register_hash(&tiger_desc);
69 #elif defined(SHA1)
70 prng->yarrow.hash = register_hash(&sha1_desc);
71 #elif defined(RIPEMD160)
72 prng->yarrow.hash = register_hash(&rmd160_desc);
73 #elif defined(RIPEMD128)
74 prng->yarrow.hash = register_hash(&rmd128_desc);
75 #elif defined(MD5)
76 prng->yarrow.hash = register_hash(&md5_desc);
77 #elif defined(MD4)
78 prng->yarrow.hash = register_hash(&md4_desc);
79 #elif defined(MD2)
80 prng->yarrow.hash = register_hash(&md2_desc);
81 #else
82 #error YARROW needs at least one HASH
83 #endif
84 if ((err = hash_is_valid(prng->yarrow.hash)) != CRYPT_OK) {
85 return err;
86 }
87
88 /* zero the memory used */
89 zeromem(prng->yarrow.pool, sizeof(prng->yarrow.pool));
90
91 return CRYPT_OK;
92 }
93
94 int yarrow_add_entropy(const unsigned char *buf, unsigned long len, prng_state *prng)
95 {
96 hash_state md;
97 int err;
98
99 _ARGCHK(buf != NULL);
100 _ARGCHK(prng != NULL);
101
102 if ((err = hash_is_valid(prng->yarrow.hash)) != CRYPT_OK) {
103 return err;
104 }
105
106 /* start the hash */
107 hash_descriptor[prng->yarrow.hash].init(&md);
108
109 /* hash the current pool */
110 hash_descriptor[prng->yarrow.hash].process(&md, prng->yarrow.pool, hash_descriptor[prng->yarrow.hash].hashsize);
111
112 /* add the new entropy */
113 hash_descriptor[prng->yarrow.hash].process(&md, buf, len);
114
115 /* store result */
116 hash_descriptor[prng->yarrow.hash].done(&md, prng->yarrow.pool);
117
118 return CRYPT_OK;
119 }
120
121 int yarrow_ready(prng_state *prng)
122 {
123 int ks, err;
124
125 _ARGCHK(prng != NULL);
126
127 if ((err = hash_is_valid(prng->yarrow.hash)) != CRYPT_OK) {
128 return err;
129 }
130
131 if ((err = cipher_is_valid(prng->yarrow.cipher)) != CRYPT_OK) {
132 return err;
133 }
134
135 /* setup CTR mode using the "pool" as the key */
136 ks = (int)hash_descriptor[prng->yarrow.hash].hashsize;
137 if ((err = cipher_descriptor[prng->yarrow.cipher].keysize(&ks)) != CRYPT_OK) {
138 return err;
139 }
140
141 if ((err = ctr_start(prng->yarrow.cipher, /* what cipher to use */
142 prng->yarrow.pool, /* IV */
143 prng->yarrow.pool, ks, /* KEY and key size */
144 0, /* number of rounds */
145 &prng->yarrow.ctr)) != CRYPT_OK) {
146 return err;
147 }
148 return CRYPT_OK;
149 }
150
151 unsigned long yarrow_read(unsigned char *buf, unsigned long len, prng_state *prng)
152 {
153 _ARGCHK(buf != NULL);
154 _ARGCHK(prng != NULL);
155
156 /* put buf in predictable state first */
157 zeromem(buf, len);
158
159 /* now randomize it */
160 if (ctr_encrypt(buf, buf, len, &prng->yarrow.ctr) != CRYPT_OK) {
161 return 0;
162 }
163 return len;
164 }
165
166 #endif
167