annotate src/prngs/rng_make_prng.c @ 209:39d5d58461d6 libtomcrypt-orig LTC_1.05

Import of libtomcrypt 1.05
author Matt Johnston <matt@ucc.asn.au>
date Wed, 06 Jul 2005 03:53:40 +0000
parents 1c15b283127b
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
191
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 *
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * Tom St Denis, [email protected], http://libtomcrypt.org
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 */
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 #include "tomcrypt.h"
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 /**
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 @file rng_make_prng.c
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 portable way to get secure random bits to feed a PRNG (Tom St Denis)
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 */
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 /**
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 Create a PRNG from a RNG
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 @param bits Number of bits of entropy desired (64 ... 1024)
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 @param wprng Index of which PRNG to setup
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 @param prng [out] PRNG state to initialize
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 @param callback A pointer to a void function for when the RNG is slow, this can be NULL
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 @return CRYPT_OK if successful
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 */
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 int rng_make_prng(int bits, int wprng, prng_state *prng,
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 void (*callback)(void))
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 unsigned char buf[256];
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 int err;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32 LTC_ARGCHK(prng != NULL);
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 /* check parameter */
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 return err;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 if (bits < 64 || bits > 1024) {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 return CRYPT_INVALID_PRNGSIZE;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43 if ((err = prng_descriptor[wprng].start(prng)) != CRYPT_OK) {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 return err;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47 bits = ((bits/8)+((bits&7)!=0?1:0)) * 2;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 if (rng_get_bytes(buf, (unsigned long)bits, callback) != (unsigned long)bits) {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 return CRYPT_ERROR_READPRNG;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
51
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52 if ((err = prng_descriptor[wprng].add_entropy(buf, (unsigned long)bits, prng)) != CRYPT_OK) {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 return err;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
54 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
55
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56 if ((err = prng_descriptor[wprng].ready(prng)) != CRYPT_OK) {
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
57 return err;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
60 #ifdef LTC_CLEAN_STACK
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 zeromem(buf, sizeof(buf));
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
62 #endif
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 return CRYPT_OK;
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64 }
1c15b283127b Import of libtomcrypt 1.02 with manual path rename rearrangement etc
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65
209
39d5d58461d6 Import of libtomcrypt 1.05
Matt Johnston <matt@ucc.asn.au>
parents: 191
diff changeset
66
39d5d58461d6 Import of libtomcrypt 1.05
Matt Johnston <matt@ucc.asn.au>
parents: 191
diff changeset
67 /* $Source: /cvs/libtom/libtomcrypt/src/prngs/rng_make_prng.c,v $ */
39d5d58461d6 Import of libtomcrypt 1.05
Matt Johnston <matt@ucc.asn.au>
parents: 191
diff changeset
68 /* $Revision: 1.3 $ */
39d5d58461d6 Import of libtomcrypt 1.05
Matt Johnston <matt@ucc.asn.au>
parents: 191
diff changeset
69 /* $Date: 2005/05/05 14:35:59 $ */