1 /* $OpenBSD: mac.c,v 1.12 2006/08/03 03:34:42 deraadt Exp $ */
3 * Copyright (c) 2001 Markus Friedl. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/types.h>
30 #include <openssl/hmac.h>
47 const EVP_MD
* (*mdfunc
)(void);
48 int truncatebits
; /* truncate digest if != 0 */
50 { "hmac-sha1", EVP_sha1
, 0, },
51 { "hmac-sha1-96", EVP_sha1
, 96 },
52 { "hmac-md5", EVP_md5
, 0 },
53 { "hmac-md5-96", EVP_md5
, 96 },
54 { "hmac-ripemd160", EVP_ripemd160
, 0 },
55 { "hmac-ripemd160@openssh.com", EVP_ripemd160
, 0 },
60 mac_init(Mac
*mac
, char *name
)
64 for (i
= 0; macs
[i
].name
; i
++) {
65 if (strcmp(name
, macs
[i
].name
) == 0) {
67 mac
->md
= (*macs
[i
].mdfunc
)();
68 if ((evp_len
= EVP_MD_size(mac
->md
)) <= 0)
69 fatal("mac %s len %d", name
, evp_len
);
70 mac
->key_len
= mac
->mac_len
= (u_int
)evp_len
;
71 if (macs
[i
].truncatebits
!= 0)
72 mac
->mac_len
= macs
[i
].truncatebits
/8;
74 debug2("mac_init: found %s", name
);
78 debug2("mac_init: unknown %s", name
);
83 mac_compute(Mac
*mac
, u_int32_t seqno
, u_char
*data
, int datalen
)
86 static u_char m
[EVP_MAX_MD_SIZE
];
90 fatal("mac_compute: no key");
91 if (mac
->mac_len
> sizeof(m
))
92 fatal("mac_compute: mac too long");
93 HMAC_Init(&c
, mac
->key
, mac
->key_len
, mac
->md
);
95 HMAC_Update(&c
, b
, sizeof(b
));
96 HMAC_Update(&c
, data
, datalen
);
97 HMAC_Final(&c
, m
, NULL
);
102 /* XXX copied from ciphers_valid */
105 mac_valid(const char *names
)
107 char *maclist
, *cp
, *p
;
109 if (names
== NULL
|| strcmp(names
, "") == 0)
111 maclist
= cp
= xstrdup(names
);
112 for ((p
= strsep(&cp
, MAC_SEP
)); p
&& *p
!= '\0';
113 (p
= strsep(&cp
, MAC_SEP
))) {
114 if (mac_init(NULL
, p
) < 0) {
115 debug("bad mac %s [%s]", p
, names
);
119 debug3("mac ok: %s [%s]", p
, names
);
122 debug3("macs ok: [%s]", names
);