diff options
Diffstat (limited to 'keyexchange/isakmpd-20041012/cookie.c')
| -rw-r--r-- | keyexchange/isakmpd-20041012/cookie.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/keyexchange/isakmpd-20041012/cookie.c b/keyexchange/isakmpd-20041012/cookie.c new file mode 100644 index 0000000..ec8f826 --- /dev/null +++ b/keyexchange/isakmpd-20041012/cookie.c @@ -0,0 +1,74 @@ +/* $OpenBSD: cookie.c,v 1.14 2004/05/14 08:42:56 hshoexer Exp $ */ +/* $EOM: cookie.c,v 1.21 1999/08/05 15:00:04 niklas Exp $ */ + +/* + * Copyright (c) 1998, 1999 Niklas Hallqvist. 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. + */ + +/* + * This code was written under funding by Ericsson Radio Systems. + */ + +#include <sys/types.h> +#include <sys/socket.h> +#include <stdlib.h> +#include <string.h> + +#include "sysdep.h" + +#include "cookie.h" +#include "exchange.h" +#include "hash.h" +#include "transport.h" +#include "util.h" + +#define COOKIE_SECRET_SIZE 16 + +/* + * Generate an anti-clogging token (a protection against an attacker forcing + * us to keep state for a flood of connection requests) a.k.a. a cookie + * at BUF, LEN bytes long. The cookie will be generated by hashing of + * information found, among otherplaces, in transport T and exchange + * EXCHANGE. + */ +void +cookie_gen(struct transport *t, struct exchange *exchange, u_int8_t *buf, + size_t len) +{ + struct hash *hash = hash_get(HASH_SHA1); + u_int8_t tmpsecret[COOKIE_SECRET_SIZE]; + struct sockaddr *name; + + hash->Init(hash->ctx); + (*t->vtbl->get_dst)(t, &name); + hash->Update(hash->ctx, (u_int8_t *)name, sysdep_sa_len(name)); + (*t->vtbl->get_src)(t, &name); + hash->Update(hash->ctx, (u_int8_t *)name, sysdep_sa_len(name)); + if (exchange->initiator == 0) + hash->Update(hash->ctx, exchange->cookies + + ISAKMP_HDR_ICOOKIE_OFF, ISAKMP_HDR_ICOOKIE_LEN); + getrandom(tmpsecret, COOKIE_SECRET_SIZE); + hash->Update(hash->ctx, tmpsecret, COOKIE_SECRET_SIZE); + hash->Final(hash->digest, hash->ctx); + memcpy(buf, hash->digest, len); +} |