/* $NetBSD: xform_tcp.c,v 1.2 2005/02/26 22:45:13 perry Exp $ */ /* $FreeBSD: sys/netipsec/xform_tcp.c,v 1.1.2.1 2004/02/14 22:24:09 bms Exp $ */ /* * Copyright (c) 2003 Bruce M. Simpson * * 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. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * 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. */ /* TCP MD5 Signature Option (RFC2385) */ #include "opt_inet.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef INET6 #include #include #endif #include #include /* * Initialize a TCP-MD5 SA. Called when the SA is being set up. * * We don't need to set up the tdb prefixed fields, as we don't use the * opencrypto code; we just perform a key length check. * * XXX: Currently we only allow a single 'magic' SPI to be used. * * This allows per-host granularity without affecting the userland * interface, which is a simple socket option toggle switch, * TCP_SIGNATURE_ENABLE. * * To allow per-service granularity requires that we have a means * of mapping port to SPI. The mandated way of doing this is to * use SPD entries to specify packet flows which get the TCP-MD5 * treatment, however the code to do this is currently unstable * and unsuitable for production use. * * Therefore we use this compromise in the meantime. */ static int tcpsignature_init(struct secasvar *sav, struct xformsw *xsp) { int keylen; if (sav->spi != htonl(TCP_SIG_SPI)) { DPRINTF(("%s: SPI %x must be TCP_SIG_SPI (0x1000)\n", __func__, sav->alg_auth)); return (EINVAL); } if (sav->alg_auth != SADB_X_AALG_TCP_MD5) { DPRINTF(("%s: unsupported authentication algorithm %u\n", __func__, sav->alg_auth)); return (EINVAL); } if (sav->key_auth == NULL) { DPRINTF(("%s: no authentication key present\n", __func__)); return (EINVAL); } keylen = _KEYLEN(sav->key_auth); if ((keylen < TCP_KEYLEN_MIN) || (keylen > TCP_KEYLEN_MAX)) { DPRINTF(("%s: invalid key length %u\n", __func__, keylen)); return (EINVAL); } return (0); } /* * Paranoia. * * Called when the SA is deleted. */ static int tcpsignature_zeroize(struct secasvar *sav) { if (sav->key_auth) bzero(_KEYBUF(sav->key_auth), _KEYLEN(sav->key_auth)); sav->tdb_cryptoid = 0; sav->tdb_authalgxform = NULL; sav->tdb_xform = NULL; return (0); } /* * Verify that an input packet passes authentication. * Called from the ipsec layer. * We do this from within tcp itself, so this routine is just a stub. */ static int tcpsignature_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) { return (0); } /* * Prepend the authentication header. * Called from the ipsec layer. * We do this from within tcp itself, so this routine is just a stub. */ static int tcpsignature_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, int skip, int protoff) { return (EINVAL); } static struct xformsw tcpsignature_xformsw = { XF_TCPSIGNATURE, XFT_AUTH, "TCPMD5", tcpsignature_init, tcpsignature_zeroize, tcpsignature_input, tcpsignature_output }; INITFN void tcpsignature_attach(void) { xform_register(&tcpsignature_xformsw); } #ifdef __FreeBSD__ SYSINIT(tcpsignature_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, tcpsignature_attach, NULL) #endif