openssh/mac.c
Damien Miller b0fb6872ed - deraadt@cvs.openbsd.org 2006/03/19 18:51:18
[atomicio.c auth-bsdauth.c auth-chall.c auth-krb5.c auth-options.c]
     [auth-pam.c auth-passwd.c auth-rh-rsa.c auth-rhosts.c auth-rsa.c]
     [auth-shadow.c auth-skey.c auth.c auth1.c auth2-chall.c]
     [auth2-hostbased.c auth2-kbdint.c auth2-none.c auth2-passwd.c]
     [auth2-pubkey.c auth2.c authfd.c authfile.c bufaux.c buffer.c]
     [canohost.c channels.c cipher-3des1.c cipher-acss.c cipher-aes.c]
     [cipher-bf1.c cipher-ctr.c cipher.c cleanup.c clientloop.c compat.c]
     [compress.c deattack.c dh.c dispatch.c dns.c entropy.c fatal.c]
     [groupaccess.c hostfile.c includes.h kex.c kexdh.c kexdhc.c]
     [kexdhs.c kexgex.c kexgexc.c kexgexs.c key.c log.c loginrec.c]
     [loginrec.h logintest.c mac.c match.c md-sha256.c md5crypt.c misc.c]
     [monitor.c monitor_fdpass.c monitor_mm.c monitor_wrap.c msg.c]
     [nchan.c packet.c progressmeter.c readconf.c readpass.c rsa.c]
     [scard.c scp.c servconf.c serverloop.c session.c sftp-client.c]
     [sftp-common.c sftp-glob.c sftp-server.c sftp.c ssh-add.c]
     [ssh-agent.c ssh-dss.c ssh-keygen.c ssh-keyscan.c ssh-keysign.c]
     [ssh-rand-helper.c ssh-rsa.c ssh.c sshconnect.c sshconnect1.c]
     [sshconnect2.c sshd.c sshlogin.c sshpty.c sshtty.c ttymodes.c]
     [uidswap.c uuencode.c xmalloc.c openbsd-compat/bsd-arc4random.c]
     [openbsd-compat/bsd-closefrom.c openbsd-compat/bsd-cygwin_util.c]
     [openbsd-compat/bsd-getpeereid.c openbsd-compat/bsd-misc.c]
     [openbsd-compat/bsd-nextstep.c openbsd-compat/bsd-snprintf.c]
     [openbsd-compat/bsd-waitpid.c openbsd-compat/fake-rfc2553.c]
     RCSID() can die
2006-03-26 00:03:21 +11:00

117 lines
3.3 KiB
C

/*
* 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"
#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;
const 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, evp_len;
for (i = 0; macs[i].name; i++) {
if (strcmp(name, macs[i].name) == 0) {
if (mac != NULL) {
mac->md = (*macs[i].mdfunc)();
if ((evp_len = EVP_MD_size(mac->md)) <= 0)
fatal("mac %s len %d", name, evp_len);
mac->key_len = mac->mac_len = (u_int)evp_len;
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);
}