diff options
author | mouring <mouring> | 2001-02-15 03:01:59 +0000 |
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committer | mouring <mouring> | 2001-02-15 03:01:59 +0000 |
commit | ea7e32e35b2d808cf84a3ac86afabe22dab2b106 (patch) | |
tree | 771ca2f4126277527fbb4a8044c2e1b867bef80a /mac.c | |
parent | 96dc654c680a97c30ec413ce966f624457a00e59 (diff) | |
download | openssh-ea7e32e35b2d808cf84a3ac86afabe22dab2b106.tar.gz |
- 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 @@ +/* + * Copyright (c) 2001 Markus Friedl. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "includes.h" +RCSID("$OpenBSD: mac.c,v 1.1 2001/02/11 12:59:24 markus Exp $"); + +#include <openssl/hmac.h> + +#include "xmalloc.h" +#include "getput.h" +#include "log.h" +#include "cipher.h" +#include "kex.h" +#include "mac.h" + +struct { + char *name; + EVP_MD * (*mdfunc)(void); + int truncatebits; /* truncate digest if != 0 */ +} macs[] = { + { "hmac-sha1", EVP_sha1, 0, }, + { "hmac-sha1-96", EVP_sha1, 96 }, + { "hmac-md5", EVP_md5, 0 }, + { "hmac-md5-96", EVP_md5, 96 }, + { "hmac-ripemd160", EVP_ripemd160, 0 }, + { "hmac-ripemd160@openssh.com", EVP_ripemd160, 0 }, + { NULL, NULL, 0 } +}; + +int +mac_init(Mac *mac, char *name) +{ + int i; + for (i = 0; macs[i].name; i++) { + if (strcmp(name, macs[i].name) == 0) { + if (mac != NULL) { + mac->md = (*macs[i].mdfunc)(); + mac->key_len = mac->mac_len = mac->md->md_size; + if (macs[i].truncatebits != 0) + mac->mac_len = macs[i].truncatebits/8; + } + debug2("mac_init: found %s", name); + return (0); + } + } + debug2("mac_init: unknown %s", name); + return (-1); +} + +u_char * +mac_compute(Mac *mac, u_int32_t seqno, u_char *data, int datalen) +{ + HMAC_CTX c; + static u_char m[EVP_MAX_MD_SIZE]; + u_char b[4]; + + if (mac->key == NULL) + fatal("mac_compute: no key"); + if (mac->mac_len > sizeof(m)) + fatal("mac_compute: mac too long"); + HMAC_Init(&c, mac->key, mac->key_len, mac->md); + PUT_32BIT(b, seqno); + HMAC_Update(&c, b, sizeof(b)); + HMAC_Update(&c, data, datalen); + HMAC_Final(&c, m, NULL); + HMAC_cleanup(&c); + return (m); +} + +/* XXX copied from ciphers_valid */ +#define MAC_SEP "," +int +mac_valid(const char *names) +{ + char *maclist, *cp, *p; + + if (names == NULL || strcmp(names, "") == 0) + return (0); + maclist = cp = xstrdup(names); + for ((p = strsep(&cp, MAC_SEP)); p && *p != '\0'; + (p = strsep(&cp, MAC_SEP))) { + if (mac_init(NULL, p) < 0) { + debug("bad mac %s [%s]", p, names); + xfree(maclist); + return (0); + } else { + debug3("mac ok: %s [%s]", p, names); + } + } + debug3("macs ok: [%s]", names); + xfree(maclist); + return (1); +} |