hm_ameth.c revision 296341 
1/*
2 * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
3 * 2007.
4 */
5/* ====================================================================
6 * Copyright (c) 2007 The OpenSSL Project.  All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 *    software must display the following acknowledgment:
22 *    "This product includes software developed by the OpenSSL Project
23 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 *    endorse or promote products derived from this software without
27 *    prior written permission. For written permission, please contact
28 *    licensing@OpenSSL.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 *    nor may "OpenSSL" appear in their names without prior written
32 *    permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 *    acknowledgment:
36 *    "This product includes software developed by the OpenSSL Project
37 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com).  This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59#include <stdio.h>
60#include "cryptlib.h"
61#include <openssl/evp.h>
62#include "asn1_locl.h"
63
64#define HMAC_TEST_PRIVATE_KEY_FORMAT
65
66/*
67 * HMAC "ASN1" method. This is just here to indicate the maximum HMAC output
68 * length and to free up an HMAC key.
69 */
70
71static int hmac_size(const EVP_PKEY *pkey)
72{
73    return EVP_MAX_MD_SIZE;
74}
75
76static void hmac_key_free(EVP_PKEY *pkey)
77{
78    ASN1_OCTET_STRING *os = (ASN1_OCTET_STRING *)pkey->pkey.ptr;
79    if (os) {
80        if (os->data)
81            OPENSSL_cleanse(os->data, os->length);
82        ASN1_OCTET_STRING_free(os);
83    }
84}
85
86static int hmac_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2)
87{
88    switch (op) {
89    case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
90        *(int *)arg2 = NID_sha1;
91        return 1;
92
93    default:
94        return -2;
95    }
96}
97
98#ifdef HMAC_TEST_PRIVATE_KEY_FORMAT
99/*
100 * A bogus private key format for test purposes. This is simply the HMAC key
101 * with "HMAC PRIVATE KEY" in the headers. When enabled the genpkey utility
102 * can be used to "generate" HMAC keys.
103 */
104
105static int old_hmac_decode(EVP_PKEY *pkey,
106                           const unsigned char **pder, int derlen)
107{
108    ASN1_OCTET_STRING *os;
109    os = ASN1_OCTET_STRING_new();
110    if (!os || !ASN1_OCTET_STRING_set(os, *pder, derlen))
111        return 0;
112    EVP_PKEY_assign(pkey, EVP_PKEY_HMAC, os);
113    return 1;
114}
115
116static int old_hmac_encode(const EVP_PKEY *pkey, unsigned char **pder)
117{
118    int inc;
119    ASN1_OCTET_STRING *os = (ASN1_OCTET_STRING *)pkey->pkey.ptr;
120    if (pder) {
121        if (!*pder) {
122            *pder = OPENSSL_malloc(os->length);
123            inc = 0;
124        } else
125            inc = 1;
126
127        memcpy(*pder, os->data, os->length);
128
129        if (inc)
130            *pder += os->length;
131    }
132
133    return os->length;
134}
135
136#endif
137
138const EVP_PKEY_ASN1_METHOD hmac_asn1_meth = {
139    EVP_PKEY_HMAC,
140    EVP_PKEY_HMAC,
141    0,
142
143    "HMAC",
144    "OpenSSL HMAC method",
145
146    0, 0, 0, 0,
147
148    0, 0, 0,
149
150    hmac_size,
151    0,
152    0, 0, 0, 0, 0, 0, 0,
153
154    hmac_key_free,
155    hmac_pkey_ctrl,
156#ifdef HMAC_TEST_PRIVATE_KEY_FORMAT
157    old_hmac_decode,
158    old_hmac_encode
159#else
160    0, 0
161#endif
162};
163