Mercurial > dropbear

annotate libtomcrypt/src/math/rand_bn.c @ 1696:d18fa38c1fd4

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
initialise variable to stop warning
author Matt Johnston <matt@ucc.asn.au>
date Thu, 28 May 2020 22:02:03 +0800
parents 6dba84798cd5
children e9dba7abd939
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
1471
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 #include "tomcrypt.h"
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 #ifdef LTC_MDSA
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12 /**
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 Generate a random number N with given bitlength (note: MSB can be 0)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 int rand_bn_bits(void *N, int bits, prng_state *prng, int wprng)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17 {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 int res, bytes;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19 unsigned char *buf, mask;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 LTC_ARGCHK(N != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 LTC_ARGCHK(bits > 1);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 /* check PRNG */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 if ((res = prng_is_valid(wprng)) != CRYPT_OK) return res;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 bytes = (bits+7) >> 3;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 mask = 0xff << (8 - bits % 8);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 /* allocate buffer */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 if ((buf = XCALLOC(1, bytes)) == NULL) return CRYPT_MEM;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 /* generate random bytes */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 if (prng_descriptor[wprng].read(buf, bytes, prng) != (unsigned long)bytes) {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 res = CRYPT_ERROR_READPRNG;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36 goto cleanup;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 /* mask bits */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 buf[0] &= ~mask;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 /* load value */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41 if ((res = mp_read_unsigned_bin(N, buf, bytes)) != CRYPT_OK) goto cleanup;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43 res = CRYPT_OK;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 cleanup:
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46 #ifdef LTC_CLEAN_STACK
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47 zeromem(buf, bytes);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 #endif
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 XFREE(buf);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 return res;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
51 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 /**
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
54 Generate a random number N in a range: 1 <= N < limit
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
55 */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56 int rand_bn_upto(void *N, void *limit, prng_state *prng, int wprng)
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
57 {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58 int res, bits;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
60 LTC_ARGCHK(N != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 LTC_ARGCHK(limit != NULL);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
62
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 bits = mp_count_bits(limit);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64 do {
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65 res = rand_bn_bits(N, bits, prng, wprng);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
66 if (res != CRYPT_OK) return res;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
67 } while (mp_cmp_d(N, 0) != LTC_MP_GT || mp_cmp(N, limit) != LTC_MP_LT);
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
68
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
69 return CRYPT_OK;
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
70 }
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
71 #endif
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
72
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
73 /* ref: $Format:%D$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
74 /* git commit: $Format:%H$ */
6dba84798cd5 Update to libtomcrypt 1.18.1, merged with Dropbear changes
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
75 /* commit time: $Format:%ai$ */