/* $FreeBSD$ */ /* $OpenBSD: ip_ipip.c,v 1.25 2002/06/10 18:04:55 itojun Exp $ */ /*- * The authors of this code are John Ioannidis (ji@tla.org), * Angelos D. Keromytis (kermit@csd.uch.gr) and * Niels Provos (provos@physnet.uni-hamburg.de). * * The original version of this code was written by John Ioannidis * for BSD/OS in Athens, Greece, in November 1995. * * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996, * by Angelos D. Keromytis. * * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis * and Niels Provos. * * Additional features in 1999 by Angelos D. Keromytis. * * Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis, * Angelos D. Keromytis and Niels Provos. * Copyright (c) 2001, Angelos D. Keromytis. * * Permission to use, copy, and modify this software with or without fee * is hereby granted, provided that this entire notice is included in * all copies of any software which is or includes a copy or * modification of this software. * You may use this code under the GNU public license if you so wish. Please * contribute changes back to the authors under this freer than GPL license * so that we may further the use of strong encryption without limitations to * all. * * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR * PURPOSE. */ /* * IP-inside-IP processing */ #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 #ifdef INET6 #include #include #include #include #include #endif #include #include int ipip_output(struct mbuf *m, struct ipsecrequest *isr, struct mbuf **mp, int skip, int protoff) { struct secasvar *sav; u_int8_t tp, otos; struct secasindex *saidx; int error; #if defined(INET) || defined(INET6) u_int8_t itos; #endif #ifdef INET struct ip *ipo; #endif /* INET */ #ifdef INET6 struct ip6_hdr *ip6, *ip6o; #endif /* INET6 */ sav = isr->sav; IPSEC_ASSERT(sav != NULL, ("null SA")); IPSEC_ASSERT(sav->sah != NULL, ("null SAH")); /* XXX Deal with empty TDB source/destination addresses. */ m_copydata(m, 0, 1, &tp); tp = (tp >> 4) & 0xff; /* Get the IP version number. */ saidx = &sav->sah->saidx; switch (saidx->dst.sa.sa_family) { #ifdef INET case AF_INET: if (saidx->src.sa.sa_family != AF_INET || saidx->src.sin.sin_addr.s_addr == INADDR_ANY || saidx->dst.sin.sin_addr.s_addr == INADDR_ANY) { DPRINTF(("%s: unspecified tunnel endpoint " "address in SA %s/%08lx\n", __func__, ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi))); error = EINVAL; goto bad; } M_PREPEND(m, sizeof(struct ip), M_NOWAIT); if (m == 0) { DPRINTF(("%s: M_PREPEND failed\n", __func__)); error = ENOBUFS; goto bad; } ipo = mtod(m, struct ip *); ipo->ip_v = IPVERSION; ipo->ip_hl = 5; ipo->ip_len = htons(m->m_pkthdr.len); ipo->ip_ttl = V_ip_defttl; ipo->ip_sum = 0; ipo->ip_src = saidx->src.sin.sin_addr; ipo->ip_dst = saidx->dst.sin.sin_addr; ipo->ip_id = ip_newid(); /* If the inner protocol is IP... */ switch (tp) { case IPVERSION: /* Save ECN notification */ m_copydata(m, sizeof(struct ip) + offsetof(struct ip, ip_tos), sizeof(u_int8_t), (caddr_t) &itos); ipo->ip_p = IPPROTO_IPIP; /* * We should be keeping tunnel soft-state and * send back ICMPs if needed. */ m_copydata(m, sizeof(struct ip) + offsetof(struct ip, ip_off), sizeof(u_int16_t), (caddr_t) &ipo->ip_off); ipo->ip_off = ntohs(ipo->ip_off); ipo->ip_off &= ~(IP_DF | IP_MF | IP_OFFMASK); ipo->ip_off = htons(ipo->ip_off); break; #ifdef INET6 case (IPV6_VERSION >> 4): { u_int32_t itos32; /* Save ECN notification. */ m_copydata(m, sizeof(struct ip) + offsetof(struct ip6_hdr, ip6_flow), sizeof(u_int32_t), (caddr_t) &itos32); itos = ntohl(itos32) >> 20; ipo->ip_p = IPPROTO_IPV6; ipo->ip_off = 0; break; } #endif /* INET6 */ default: goto nofamily; } otos = 0; ip_ecn_ingress(ECN_ALLOWED, &otos, &itos); ipo->ip_tos = otos; break; #endif /* INET */ #ifdef INET6 case AF_INET6: if (IN6_IS_ADDR_UNSPECIFIED(&saidx->dst.sin6.sin6_addr) || saidx->src.sa.sa_family != AF_INET6 || IN6_IS_ADDR_UNSPECIFIED(&saidx->src.sin6.sin6_addr)) { DPRINTF(("%s: unspecified tunnel endpoint " "address in SA %s/%08lx\n", __func__, ipsec_address(&saidx->dst), (u_long) ntohl(sav->spi))); error = ENOBUFS; goto bad; } /* scoped address handling */ ip6 = mtod(m, struct ip6_hdr *); in6_clearscope(&ip6->ip6_src); in6_clearscope(&ip6->ip6_dst); M_PREPEND(m, sizeof(struct ip6_hdr), M_NOWAIT); if (m == 0) { DPRINTF(("%s: M_PREPEND failed\n", __func__)); error = ENOBUFS; goto bad; } /* Initialize IPv6 header */ ip6o = mtod(m, struct ip6_hdr *); ip6o->ip6_flow = 0; ip6o->ip6_vfc &= ~IPV6_VERSION_MASK; ip6o->ip6_vfc |= IPV6_VERSION; ip6o->ip6_hlim = IPV6_DEFHLIM; ip6o->ip6_dst = saidx->dst.sin6.sin6_addr; ip6o->ip6_src = saidx->src.sin6.sin6_addr; ip6o->ip6_plen = htons(m->m_pkthdr.len - sizeof(*ip6)); switch (tp) { #ifdef INET case IPVERSION: /* Save ECN notification */ m_copydata(m, sizeof(struct ip6_hdr) + offsetof(struct ip, ip_tos), sizeof(u_int8_t), (caddr_t) &itos); /* This is really IPVERSION. */ ip6o->ip6_nxt = IPPROTO_IPIP; break; #endif /* INET */ case (IPV6_VERSION >> 4): { u_int32_t itos32; /* Save ECN notification. */ m_copydata(m, sizeof(struct ip6_hdr) + offsetof(struct ip6_hdr, ip6_flow), sizeof(u_int32_t), (caddr_t) &itos32); itos = ntohl(itos32) >> 20; ip6o->ip6_nxt = IPPROTO_IPV6; break; } default: goto nofamily; } otos = 0; ip_ecn_ingress(V_ip6_ipsec_ecn, &otos, &itos); ip6o->ip6_flow |= htonl((u_int32_t) otos << 20); break; #endif /* INET6 */ default: nofamily: DPRINTF(("%s: unsupported protocol family %u\n", __func__, saidx->dst.sa.sa_family)); error = EAFNOSUPPORT; /* XXX diffs from openbsd */ goto bad; } *mp = m; return (0); bad: if (m) m_freem(m); *mp = NULL; return (error); } static int ipe4_init(struct secasvar *sav, struct xformsw *xsp) { sav->tdb_xform = xsp; return 0; } static int ipe4_zeroize(struct secasvar *sav) { sav->tdb_xform = NULL; return 0; } static int ipe4_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff) { /* This is a rather serious mistake, so no conditional printing. */ printf("%s: should never be called\n", __func__); if (m) m_freem(m); return EOPNOTSUPP; } static struct xformsw ipe4_xformsw = { XF_IP4, 0, "IPv4 Simple Encapsulation", ipe4_init, ipe4_zeroize, ipe4_input, ipip_output, }; static void ipe4_attach(void) { xform_register(&ipe4_xformsw); } SYSINIT(ipe4_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipe4_attach, NULL);