Mercurial > dropbear

comparison libtomcrypt/src/pk/rsa/rsa_sign_hash.c @ 285:1b9e69c058d2

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
propagate from branch 'au.asn.ucc.matt.ltc.dropbear' (head 20dccfc09627970a312d77fb41dc2970b62689c3) to branch 'au.asn.ucc.matt.dropbear' (head fdf4a7a3b97ae5046139915de7e40399cceb2c01)
author Matt Johnston <matt@ucc.asn.au>
date Wed, 08 Mar 2006 13:23:58 +0000
parents
children 0cbe8f6dbf9e
comparison
equal deleted inserted replaced
281:997e6f7dc01e 285:1b9e69c058d2
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 #include "tomcrypt.h"
12
13 /**
14 @file rsa_sign_hash.c
15 RSA PKCS v2 PSS sign hash, Tom St Denis
16 */
17
18 #ifdef MRSA
19
20 /**
21 (PKCS #1, v2.0) PSS pad then sign
22 @param in The hash to sign
23 @param inlen The length of the hash to sign (octets)
24 @param out [out] The signature
25 @param outlen [in/out] The max size and resulting size of the signature
26 @param prng An active PRNG state
27 @param prng_idx The index of the PRNG desired
28 @param hash_idx The index of the hash desired
29 @param saltlen The length of the salt desired (octets)
30 @param key The private RSA key to use
31 @return CRYPT_OK if successful
32 */
33 int rsa_sign_hash(const unsigned char *in, unsigned long inlen,
34 unsigned char *out, unsigned long *outlen,
35 prng_state *prng, int prng_idx,
36 int hash_idx, unsigned long saltlen,
37 rsa_key *key)
38 {
39 unsigned long modulus_bitlen, modulus_bytelen, x;
40 int err;
41
42 LTC_ARGCHK(in != NULL);
43 LTC_ARGCHK(out != NULL);
44 LTC_ARGCHK(outlen != NULL);
45 LTC_ARGCHK(key != NULL);
46
47 /* valid prng and hash ? */
48 if ((err = prng_is_valid(prng_idx)) != CRYPT_OK) {
49 return err;
50 }
51 if ((err = hash_is_valid(hash_idx)) != CRYPT_OK) {
52 return err;
53 }
54
55 /* get modulus len in bits */
56 modulus_bitlen = mp_count_bits(&(key->N));
57
58 /* outlen must be at least the size of the modulus */
59 modulus_bytelen = mp_unsigned_bin_size(&(key->N));
60 if (modulus_bytelen > *outlen) {
61 return CRYPT_BUFFER_OVERFLOW;
62 }
63
64 /* PSS pad the key */
65 x = *outlen;
66 if ((err = pkcs_1_pss_encode(in, inlen, saltlen, prng, prng_idx,
67 hash_idx, modulus_bitlen, out, &x)) != CRYPT_OK) {
68 return err;
69 }
70
71 /* RSA encode it */
72 return rsa_exptmod(out, x, out, outlen, PK_PRIVATE, key);
73 }
74
75 #endif /* MRSA */
76
77 /* $Source: /cvs/libtom/libtomcrypt/src/pk/rsa/rsa_sign_hash.c,v $ */
78 /* $Revision: 1.3 $ */
79 /* $Date: 2005/05/05 14:35:59 $ */