annotate libtomcrypt/src/pk/dsa/dsa_shared_secret.c @ 382:0cbe8f6dbf9e

propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f) to branch 'au.asn.ucc.matt.dropbear' (head 02c413252c90e9de8e03d91e9939dde3029f5c0a)
author Matt Johnston <matt@ucc.asn.au>
date Thu, 11 Jan 2007 02:41:05 +0000
parents
children f849a5ca2efc
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
382
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
4 * algorithms in a highly modular and flexible manner.
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
5 *
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
7 * guarantee it works.
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 *
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * Tom St Denis, [email protected], http://libtomcrypt.com
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
10 */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
11 #include "tomcrypt.h"
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
12
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
13 /**
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
14 @file dsa_shared_secret.c
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
15 DSA Crypto, Tom St Denis
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
17
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
18 #ifdef MDSA
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
19
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 /**
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 Create a DSA shared secret between two keys
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
22 @param private_key The private DSA key (the exponent)
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
23 @param base The base of the exponentiation (allows this to be used for both encrypt and decrypt)
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
24 @param public_key The public key
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 @param out [out] Destination of the shared secret
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
26 @param outlen [in/out] The max size and resulting size of the shared secret
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
27 @return CRYPT_OK if successful
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
28 */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
29 int dsa_shared_secret(void *private_key, void *base,
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
30 dsa_key *public_key,
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
31 unsigned char *out, unsigned long *outlen)
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
32 {
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
33 unsigned long x;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
34 void *res;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
35 int err;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
36
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
37 LTC_ARGCHK(private_key != NULL);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
38 LTC_ARGCHK(public_key != NULL);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
39 LTC_ARGCHK(out != NULL);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
40 LTC_ARGCHK(outlen != NULL);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
41
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
42 /* make new point */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
43 if ((err = mp_init(&res)) != CRYPT_OK) {
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
44 return err;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
45 }
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
46
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
47 if ((err = mp_exptmod(base, private_key, public_key->p, res)) != CRYPT_OK) {
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 mp_clear(res);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
49 return err;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
50 }
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
51
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52 x = (unsigned long)mp_unsigned_bin_size(res);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 if (*outlen < x) {
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
54 *outlen = x;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
55 err = CRYPT_BUFFER_OVERFLOW;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56 goto done;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
57 }
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58 zeromem(out, x);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59 if ((err = mp_to_unsigned_bin(res, out + (x - mp_unsigned_bin_size(res)))) != CRYPT_OK) { goto done; }
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
60
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 err = CRYPT_OK;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
62 *outlen = x;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
63 done:
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
64 mp_clear(res);
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65 return err;
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
66 }
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
67
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
68 #endif
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
69 /* $Source: /cvs/libtom/libtomcrypt/src/pk/dsa/dsa_shared_secret.c,v $ */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
70 /* $Revision: 1.7 $ */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
71 /* $Date: 2006/12/04 03:18:43 $ */
0cbe8f6dbf9e propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 2af22fb4e878750b88f80f90d439b316d229796f)
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
72