1127785Sbms/* $FreeBSD$ */ 2127785Sbms 3139823Simp/*- 4127785Sbms * Copyright (c) 2003 Bruce M. Simpson <bms@spc.org> 5127785Sbms * 6127785Sbms * Redistribution and use in source and binary forms, with or without 7127785Sbms * modification, are permitted provided that the following conditions 8127785Sbms * are met: 9127785Sbms * 10127785Sbms * 1. Redistributions of source code must retain the above copyright 11127785Sbms * notice, this list of conditions and the following disclaimer. 12127785Sbms * 2. Redistributions in binary form must reproduce the above copyright 13127785Sbms * notice, this list of conditions and the following disclaimer in the 14127785Sbms * documentation and/or other materials provided with the distribution. 15127785Sbms * 3. The name of the author may not be used to endorse or promote products 16127785Sbms * derived from this software without specific prior written permission. 17127785Sbms * 18127785Sbms * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19127785Sbms * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20127785Sbms * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21127785Sbms * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22127785Sbms * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23127785Sbms * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24127785Sbms * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25127785Sbms * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26127785Sbms * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27127785Sbms * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28127785Sbms */ 29127785Sbms 30127785Sbms/* TCP MD5 Signature Option (RFC2385) */ 31127785Sbms#include "opt_inet.h" 32127785Sbms#include "opt_inet6.h" 33127785Sbms 34127785Sbms#include <sys/param.h> 35127785Sbms#include <sys/systm.h> 36127785Sbms#include <sys/mbuf.h> 37127785Sbms#include <sys/lock.h> 38127785Sbms#include <sys/socket.h> 39127785Sbms#include <sys/kernel.h> 40127785Sbms#include <sys/protosw.h> 41127785Sbms#include <sys/sysctl.h> 42127785Sbms 43127785Sbms#include <netinet/in.h> 44127785Sbms#include <netinet/in_systm.h> 45127785Sbms#include <netinet/ip.h> 46127785Sbms#include <netinet/ip_var.h> 47127785Sbms#include <netinet/tcp.h> 48127785Sbms#include <netinet/tcp_var.h> 49127785Sbms 50127785Sbms#include <net/route.h> 51195699Srwatson#include <net/vnet.h> 52195699Srwatson 53127785Sbms#include <netipsec/ipsec.h> 54127785Sbms#include <netipsec/xform.h> 55127785Sbms 56127785Sbms#ifdef INET6 57127785Sbms#include <netinet/ip6.h> 58127785Sbms#include <netipsec/ipsec6.h> 59127785Sbms#endif 60127785Sbms 61127785Sbms#include <netipsec/key.h> 62127785Sbms#include <netipsec/key_debug.h> 63127785Sbms 64127785Sbms/* 65127785Sbms * Initialize a TCP-MD5 SA. Called when the SA is being set up. 66127785Sbms * 67127785Sbms * We don't need to set up the tdb prefixed fields, as we don't use the 68127785Sbms * opencrypto code; we just perform a key length check. 69127785Sbms * 70127785Sbms * XXX: Currently we only allow a single 'magic' SPI to be used. 71127785Sbms * 72127785Sbms * This allows per-host granularity without affecting the userland 73127785Sbms * interface, which is a simple socket option toggle switch, 74127785Sbms * TCP_SIGNATURE_ENABLE. 75127785Sbms * 76127785Sbms * To allow per-service granularity requires that we have a means 77127785Sbms * of mapping port to SPI. The mandated way of doing this is to 78127785Sbms * use SPD entries to specify packet flows which get the TCP-MD5 79127785Sbms * treatment, however the code to do this is currently unstable 80127785Sbms * and unsuitable for production use. 81127785Sbms * 82127785Sbms * Therefore we use this compromise in the meantime. 83127785Sbms */ 84127785Sbmsstatic int 85127785Sbmstcpsignature_init(struct secasvar *sav, struct xformsw *xsp) 86127785Sbms{ 87127785Sbms int keylen; 88127785Sbms 89127785Sbms if (sav->spi != htonl(TCP_SIG_SPI)) { 90127785Sbms DPRINTF(("%s: SPI must be TCP_SIG_SPI (0x1000)\n", 91128478Sbms __func__)); 92127785Sbms return (EINVAL); 93127785Sbms } 94127785Sbms if (sav->alg_auth != SADB_X_AALG_TCP_MD5) { 95127785Sbms DPRINTF(("%s: unsupported authentication algorithm %u\n", 96127785Sbms __func__, sav->alg_auth)); 97127785Sbms return (EINVAL); 98127785Sbms } 99127785Sbms if (sav->key_auth == NULL) { 100127785Sbms DPRINTF(("%s: no authentication key present\n", __func__)); 101127785Sbms return (EINVAL); 102127785Sbms } 103127785Sbms keylen = _KEYLEN(sav->key_auth); 104127785Sbms if ((keylen < TCP_KEYLEN_MIN) || (keylen > TCP_KEYLEN_MAX)) { 105127785Sbms DPRINTF(("%s: invalid key length %u\n", __func__, keylen)); 106127785Sbms return (EINVAL); 107127785Sbms } 108127785Sbms 109127785Sbms return (0); 110127785Sbms} 111127785Sbms 112127785Sbms/* 113127785Sbms * Paranoia. 114127785Sbms * 115127785Sbms * Called when the SA is deleted. 116127785Sbms */ 117127785Sbmsstatic int 118127785Sbmstcpsignature_zeroize(struct secasvar *sav) 119127785Sbms{ 120127785Sbms 121127785Sbms if (sav->key_auth) 122157123Sgnn bzero(sav->key_auth->key_data, _KEYLEN(sav->key_auth)); 123127785Sbms 124127785Sbms sav->tdb_cryptoid = 0; 125127785Sbms sav->tdb_authalgxform = NULL; 126127785Sbms sav->tdb_xform = NULL; 127127785Sbms 128127785Sbms return (0); 129127785Sbms} 130127785Sbms 131127785Sbms/* 132127785Sbms * Verify that an input packet passes authentication. 133127785Sbms * Called from the ipsec layer. 134127785Sbms * We do this from within tcp itself, so this routine is just a stub. 135127785Sbms */ 136127785Sbmsstatic int 137127785Sbmstcpsignature_input(struct mbuf *m, struct secasvar *sav, int skip, 138127785Sbms int protoff) 139127785Sbms{ 140127785Sbms 141127785Sbms return (0); 142127785Sbms} 143127785Sbms 144127785Sbms/* 145127785Sbms * Prepend the authentication header. 146127785Sbms * Called from the ipsec layer. 147127785Sbms * We do this from within tcp itself, so this routine is just a stub. 148127785Sbms */ 149127785Sbmsstatic int 150127785Sbmstcpsignature_output(struct mbuf *m, struct ipsecrequest *isr, 151127785Sbms struct mbuf **mp, int skip, int protoff) 152127785Sbms{ 153127785Sbms 154127785Sbms return (EINVAL); 155127785Sbms} 156127785Sbms 157127785Sbmsstatic struct xformsw tcpsignature_xformsw = { 158127785Sbms XF_TCPSIGNATURE, XFT_AUTH, "TCPMD5", 159127785Sbms tcpsignature_init, tcpsignature_zeroize, 160127785Sbms tcpsignature_input, tcpsignature_output 161127785Sbms}; 162127785Sbms 163127785Sbmsstatic void 164127785Sbmstcpsignature_attach(void) 165127785Sbms{ 166127785Sbms 167127785Sbms xform_register(&tcpsignature_xformsw); 168127785Sbms} 169127785Sbms 170127785SbmsSYSINIT(tcpsignature_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, 171177481Sbz tcpsignature_attach, NULL); 172