diff options
author | Ben Lindstrom <mouring@eviladmin.org> | 2001-02-15 03:01:59 +0000 |
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committer | Ben Lindstrom <mouring@eviladmin.org> | 2001-02-15 03:01:59 +0000 |
commit | 06b33aa0e83163f3dcd679317afec1ee95910512 (patch) | |
tree | eae5cbd1cd71619bdd1e5d4a28e6bb96057f4479 /mac.c | |
parent | 4272ed803ff309f1fdb9c149b9cf083769f53744 (diff) |
- markus@cvs.openbsd.org 2001/02/11 12:59:25
[Makefile.in sshd.8 sshconnect2.c readconf.h readconf.c packet.c
sshd.c ssh.c ssh.1 servconf.h servconf.c myproposal.h kex.h kex.c]
1) clean up the MAC support for SSH-2
2) allow you to specify the MAC with 'ssh -m'
3) or the 'MACs' keyword in ssh(d)_config
4) add hmac-{md5,sha1}-96
ok stevesk@, provos@
Diffstat (limited to 'mac.c')
-rw-r--r-- | mac.c | 114 |
1 files changed, 114 insertions, 0 deletions
@@ -0,0 +1,114 @@ | |||
1 | /* | ||
2 | * Copyright (c) 2001 Markus Friedl. All rights reserved. | ||
3 | * | ||
4 | * Redistribution and use in source and binary forms, with or without | ||
5 | * modification, are permitted provided that the following conditions | ||
6 | * are met: | ||
7 | * 1. Redistributions of source code must retain the above copyright | ||
8 | * notice, this list of conditions and the following disclaimer. | ||
9 | * 2. Redistributions in binary form must reproduce the above copyright | ||
10 | * notice, this list of conditions and the following disclaimer in the | ||
11 | * documentation and/or other materials provided with the distribution. | ||
12 | * | ||
13 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | ||
14 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | ||
15 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | ||
16 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | ||
17 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | ||
18 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | ||
19 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | ||
20 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
21 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | ||
22 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
23 | */ | ||
24 | |||
25 | #include "includes.h" | ||
26 | RCSID("$OpenBSD: mac.c,v 1.1 2001/02/11 12:59:24 markus Exp $"); | ||
27 | |||
28 | #include <openssl/hmac.h> | ||
29 | |||
30 | #include "xmalloc.h" | ||
31 | #include "getput.h" | ||
32 | #include "log.h" | ||
33 | #include "cipher.h" | ||
34 | #include "kex.h" | ||
35 | #include "mac.h" | ||
36 | |||
37 | struct { | ||
38 | char *name; | ||
39 | EVP_MD * (*mdfunc)(void); | ||
40 | int truncatebits; /* truncate digest if != 0 */ | ||
41 | } macs[] = { | ||
42 | { "hmac-sha1", EVP_sha1, 0, }, | ||
43 | { "hmac-sha1-96", EVP_sha1, 96 }, | ||
44 | { "hmac-md5", EVP_md5, 0 }, | ||
45 | { "hmac-md5-96", EVP_md5, 96 }, | ||
46 | { "hmac-ripemd160", EVP_ripemd160, 0 }, | ||
47 | { "hmac-ripemd160@openssh.com", EVP_ripemd160, 0 }, | ||
48 | { NULL, NULL, 0 } | ||
49 | }; | ||
50 | |||
51 | int | ||
52 | mac_init(Mac *mac, char *name) | ||
53 | { | ||
54 | int i; | ||
55 | for (i = 0; macs[i].name; i++) { | ||
56 | if (strcmp(name, macs[i].name) == 0) { | ||
57 | if (mac != NULL) { | ||
58 | mac->md = (*macs[i].mdfunc)(); | ||
59 | mac->key_len = mac->mac_len = mac->md->md_size; | ||
60 | if (macs[i].truncatebits != 0) | ||
61 | mac->mac_len = macs[i].truncatebits/8; | ||
62 | } | ||
63 | debug2("mac_init: found %s", name); | ||
64 | return (0); | ||
65 | } | ||
66 | } | ||
67 | debug2("mac_init: unknown %s", name); | ||
68 | return (-1); | ||
69 | } | ||
70 | |||
71 | u_char * | ||
72 | mac_compute(Mac *mac, u_int32_t seqno, u_char *data, int datalen) | ||
73 | { | ||
74 | HMAC_CTX c; | ||
75 | static u_char m[EVP_MAX_MD_SIZE]; | ||
76 | u_char b[4]; | ||
77 | |||
78 | if (mac->key == NULL) | ||
79 | fatal("mac_compute: no key"); | ||
80 | if (mac->mac_len > sizeof(m)) | ||
81 | fatal("mac_compute: mac too long"); | ||
82 | HMAC_Init(&c, mac->key, mac->key_len, mac->md); | ||
83 | PUT_32BIT(b, seqno); | ||
84 | HMAC_Update(&c, b, sizeof(b)); | ||
85 | HMAC_Update(&c, data, datalen); | ||
86 | HMAC_Final(&c, m, NULL); | ||
87 | HMAC_cleanup(&c); | ||
88 | return (m); | ||
89 | } | ||
90 | |||
91 | /* XXX copied from ciphers_valid */ | ||
92 | #define MAC_SEP "," | ||
93 | int | ||
94 | mac_valid(const char *names) | ||
95 | { | ||
96 | char *maclist, *cp, *p; | ||
97 | |||
98 | if (names == NULL || strcmp(names, "") == 0) | ||
99 | return (0); | ||
100 | maclist = cp = xstrdup(names); | ||
101 | for ((p = strsep(&cp, MAC_SEP)); p && *p != '\0'; | ||
102 | (p = strsep(&cp, MAC_SEP))) { | ||
103 | if (mac_init(NULL, p) < 0) { | ||
104 | debug("bad mac %s [%s]", p, names); | ||
105 | xfree(maclist); | ||
106 | return (0); | ||
107 | } else { | ||
108 | debug3("mac ok: %s [%s]", p, names); | ||
109 | } | ||
110 | } | ||
111 | debug3("macs ok: [%s]", names); | ||
112 | xfree(maclist); | ||
113 | return (1); | ||
114 | } | ||