/*- * Copyright (c) 2006 The FreeBSD Project. * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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. * * $FreeBSD$ */ #include "opt_inet.h" #include "opt_inet6.h" #include "opt_enc.h" #include #include #include #include #include #include #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 #define ENCMTU (1024+512) /* XXX this define must have the same value as in OpenBSD */ #define M_CONF 0x0400 /* payload was encrypted (ESP-transport) */ #define M_AUTH 0x0800 /* payload was authenticated (AH or ESP auth) */ #define M_AUTH_AH 0x2000 /* header was authenticated (AH) */ struct enchdr { u_int32_t af; u_int32_t spi; u_int32_t flags; }; struct ifnet *encif; static struct mtx enc_mtx; struct enc_softc { struct ifnet *sc_ifp; }; static int enc_ioctl(struct ifnet *, u_long, caddr_t); static int enc_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, struct route *ro); static int enc_clone_create(struct if_clone *, int, caddr_t); static void enc_clone_destroy(struct ifnet *); static struct if_clone *enc_cloner; static const char encname[] = "enc"; /* * Sysctls. */ /* * Before and after are relative to when we are stripping the * outer IP header. */ static SYSCTL_NODE(_net, OID_AUTO, enc, CTLFLAG_RW, 0, "enc sysctl"); static SYSCTL_NODE(_net_enc, OID_AUTO, in, CTLFLAG_RW, 0, "enc input sysctl"); static int ipsec_filter_mask_in = ENC_BEFORE; SYSCTL_INT(_net_enc_in, OID_AUTO, ipsec_filter_mask, CTLFLAG_RW, &ipsec_filter_mask_in, 0, "IPsec input firewall filter mask"); static int ipsec_bpf_mask_in = ENC_BEFORE; SYSCTL_INT(_net_enc_in, OID_AUTO, ipsec_bpf_mask, CTLFLAG_RW, &ipsec_bpf_mask_in, 0, "IPsec input bpf mask"); static SYSCTL_NODE(_net_enc, OID_AUTO, out, CTLFLAG_RW, 0, "enc output sysctl"); static int ipsec_filter_mask_out = ENC_BEFORE; SYSCTL_INT(_net_enc_out, OID_AUTO, ipsec_filter_mask, CTLFLAG_RW, &ipsec_filter_mask_out, 0, "IPsec output firewall filter mask"); static int ipsec_bpf_mask_out = ENC_BEFORE|ENC_AFTER; SYSCTL_INT(_net_enc_out, OID_AUTO, ipsec_bpf_mask, CTLFLAG_RW, &ipsec_bpf_mask_out, 0, "IPsec output bpf mask"); static void enc_clone_destroy(struct ifnet *ifp) { KASSERT(ifp != encif, ("%s: destroying encif", __func__)); bpfdetach(ifp); if_detach(ifp); if_free(ifp); } static int enc_clone_create(struct if_clone *ifc, int unit, caddr_t params) { struct ifnet *ifp; struct enc_softc *sc; sc = malloc(sizeof(*sc), M_DEVBUF, M_WAITOK|M_ZERO); ifp = sc->sc_ifp = if_alloc(IFT_ENC); if (ifp == NULL) { free(sc, M_DEVBUF); return (ENOSPC); } if_initname(ifp, encname, unit); ifp->if_mtu = ENCMTU; ifp->if_ioctl = enc_ioctl; ifp->if_output = enc_output; ifp->if_snd.ifq_maxlen = ifqmaxlen; ifp->if_softc = sc; if_attach(ifp); bpfattach(ifp, DLT_ENC, sizeof(struct enchdr)); mtx_lock(&enc_mtx); /* grab a pointer to enc0, ignore the rest */ if (encif == NULL) encif = ifp; mtx_unlock(&enc_mtx); return (0); } static int enc_modevent(module_t mod, int type, void *data) { switch (type) { case MOD_LOAD: mtx_init(&enc_mtx, "enc mtx", NULL, MTX_DEF); enc_cloner = if_clone_simple(encname, enc_clone_create, enc_clone_destroy, 1); break; case MOD_UNLOAD: printf("enc module unload - not possible for this module\n"); return (EINVAL); default: return (EOPNOTSUPP); } return (0); } static moduledata_t enc_mod = { "if_enc", enc_modevent, 0 }; DECLARE_MODULE(if_enc, enc_mod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY); static int enc_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst, struct route *ro) { m_freem(m); return (0); } /* * Process an ioctl request. */ /* ARGSUSED */ static int enc_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) { int error = 0; mtx_lock(&enc_mtx); switch (cmd) { case SIOCSIFFLAGS: if (ifp->if_flags & IFF_UP) ifp->if_drv_flags |= IFF_DRV_RUNNING; else ifp->if_drv_flags &= ~IFF_DRV_RUNNING; break; default: error = EINVAL; } mtx_unlock(&enc_mtx); return (error); } int ipsec_filter(struct mbuf **mp, int dir, int flags) { int error, i; struct ip *ip; KASSERT(encif != NULL, ("%s: encif is null", __func__)); KASSERT(flags & (ENC_IN|ENC_OUT), ("%s: invalid flags: %04x", __func__, flags)); if ((encif->if_drv_flags & IFF_DRV_RUNNING) == 0) return (0); if (flags & ENC_IN) { if ((flags & ipsec_filter_mask_in) == 0) return (0); } else { if ((flags & ipsec_filter_mask_out) == 0) return (0); } /* Skip pfil(9) if no filters are loaded */ if (1 #ifdef INET && !PFIL_HOOKED(&V_inet_pfil_hook) #endif #ifdef INET6 && !PFIL_HOOKED(&V_inet6_pfil_hook) #endif ) { return (0); } i = min((*mp)->m_pkthdr.len, max_protohdr); if ((*mp)->m_len < i) { *mp = m_pullup(*mp, i); if (*mp == NULL) { printf("%s: m_pullup failed\n", __func__); return (-1); } } error = 0; ip = mtod(*mp, struct ip *); switch (ip->ip_v) { #ifdef INET case 4: error = pfil_run_hooks(&V_inet_pfil_hook, mp, encif, dir, NULL); break; #endif #ifdef INET6 case 6: error = pfil_run_hooks(&V_inet6_pfil_hook, mp, encif, dir, NULL); break; #endif default: printf("%s: unknown IP version\n", __func__); } /* * If the mbuf was consumed by the filter for requeueing (dummynet, etc) * then error will be zero but we still want to return an error to our * caller so the null mbuf isn't forwarded further. */ if (*mp == NULL && error == 0) return (-1); /* Consumed by the filter */ if (*mp == NULL) return (error); if (error != 0) goto bad; return (error); bad: m_freem(*mp); *mp = NULL; return (error); } void ipsec_bpf(struct mbuf *m, struct secasvar *sav, int af, int flags) { int mflags; struct enchdr hdr; KASSERT(encif != NULL, ("%s: encif is null", __func__)); KASSERT(flags & (ENC_IN|ENC_OUT), ("%s: invalid flags: %04x", __func__, flags)); if ((encif->if_drv_flags & IFF_DRV_RUNNING) == 0) return; if (flags & ENC_IN) { if ((flags & ipsec_bpf_mask_in) == 0) return; } else { if ((flags & ipsec_bpf_mask_out) == 0) return; } if (bpf_peers_present(encif->if_bpf)) { mflags = 0; hdr.spi = 0; if (!sav) { struct m_tag *mtag; mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); if (mtag != NULL) { struct tdb_ident *tdbi; tdbi = (struct tdb_ident *) (mtag + 1); if (tdbi->alg_enc != SADB_EALG_NONE) mflags |= M_CONF; if (tdbi->alg_auth != SADB_AALG_NONE) mflags |= M_AUTH; hdr.spi = tdbi->spi; } } else { if (sav->alg_enc != SADB_EALG_NONE) mflags |= M_CONF; if (sav->alg_auth != SADB_AALG_NONE) mflags |= M_AUTH; hdr.spi = sav->spi; } /* * We need to prepend the address family as a four byte * field. Cons up a dummy header to pacify bpf. This * is safe because bpf will only read from the mbuf * (i.e., it won't try to free it or keep a pointer a * to it). */ hdr.af = af; /* hdr.spi already set above */ hdr.flags = mflags; bpf_mtap2(encif->if_bpf, &hdr, sizeof(hdr), m); } }