annotate rng_make_prng.c @ 125:d16fc1b2223d libtomcrypt

merge of 8231809d2509aa54773443786e3123766438d924 and e30f886c9c14efb01f49297b3fb6b97c8868fd88
author Matt Johnston <matt@ucc.asn.au>
date Tue, 14 Sep 2004 13:28:31 +0000
parents d7da3b1e1540
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 *
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * Tom St Denis, [email protected], http://libtomcrypt.org
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 */
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 /* portable way to get secure random bits to feed a PRNG */
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 #include "mycrypt.h"
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 int rng_make_prng(int bits, int wprng, prng_state *prng,
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 void (*callback)(void))
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17 unsigned char buf[256];
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 int err;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 _ARGCHK(prng != NULL);
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 /* check parameter */
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 return err;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 if (bits < 64 || bits > 1024) {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 return CRYPT_INVALID_PRNGSIZE;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 if ((err = prng_descriptor[wprng].start(prng)) != CRYPT_OK) {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32 return err;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 bits = ((bits/8)+((bits&7)!=0?1:0)) * 2;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 if (rng_get_bytes(buf, (unsigned long)bits, callback) != (unsigned long)bits) {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 return CRYPT_ERROR_READPRNG;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 if ((err = prng_descriptor[wprng].add_entropy(buf, (unsigned long)bits, prng)) != CRYPT_OK) {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 return err;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 if ((err = prng_descriptor[wprng].ready(prng)) != CRYPT_OK) {
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 return err;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 #ifdef CLEAN_STACK
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 zeromem(buf, sizeof(buf));
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 #endif
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
51 return CRYPT_OK;
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52 }
d7da3b1e1540 put back the 0.95 makefile which was inadvertently merged over
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53