930 lines
23 KiB
C
930 lines
23 KiB
C
/* $FreeBSD$ */
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/* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */
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/*-
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* The authors of this code are John Ioannidis (ji@tla.org),
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* Angelos D. Keromytis (kermit@csd.uch.gr) and
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* Niels Provos (provos@physnet.uni-hamburg.de).
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*
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* This code was written by John Ioannidis for BSD/OS in Athens, Greece,
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* in November 1995.
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*
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* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
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* by Angelos D. Keromytis.
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*
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* Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
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* and Niels Provos.
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*
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* Additional features in 1999 by Angelos D. Keromytis.
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*
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* Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
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* Angelos D. Keromytis and Niels Provos.
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* Copyright (c) 2001, Angelos D. Keromytis.
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*
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* Permission to use, copy, and modify this software with or without fee
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* is hereby granted, provided that this entire notice is included in
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* all copies of any software which is or includes a copy or
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* modification of this software.
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* You may use this code under the GNU public license if you so wish. Please
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* contribute changes back to the authors under this freer than GPL license
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* so that we may further the use of strong encryption without limitations to
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* all.
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*
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* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
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* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
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* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
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* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
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* PURPOSE.
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*/
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/*
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* IPsec input processing.
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*/
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#include "opt_inet.h"
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#include "opt_inet6.h"
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#include "opt_ipsec.h"
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#include "opt_enc.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#include <sys/domain.h>
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#include <sys/protosw.h>
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#include <sys/socket.h>
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#include <sys/errno.h>
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#include <sys/syslog.h>
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#include <net/if.h>
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#include <net/if_var.h>
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#include <net/pfil.h>
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#include <net/netisr.h>
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#include <net/vnet.h>
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/ip.h>
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#include <netinet/ip_var.h>
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#include <netinet/in_var.h>
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#include <netinet/ip6.h>
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#ifdef INET6
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#include <netinet6/ip6_var.h>
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#endif
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#include <netinet/in_pcb.h>
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#ifdef INET6
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#include <netinet/icmp6.h>
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#endif
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#include <netipsec/ipsec.h>
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#ifdef INET6
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#include <netipsec/ipsec6.h>
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#endif
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#include <netipsec/ah_var.h>
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#include <netipsec/esp.h>
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#include <netipsec/esp_var.h>
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#include <netipsec/ipcomp_var.h>
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#include <netipsec/key.h>
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#include <netipsec/keydb.h>
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#include <netipsec/xform.h>
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#include <netinet6/ip6protosw.h>
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#include <machine/in_cksum.h>
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#include <machine/stdarg.h>
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#ifdef DEV_ENC
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#include <net/if_enc.h>
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#endif
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#define IPSEC_ISTAT(proto, name) do { \
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if ((proto) == IPPROTO_ESP) \
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ESPSTAT_INC(esps_##name); \
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else if ((proto) == IPPROTO_AH) \
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AHSTAT_INC(ahs_##name); \
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else \
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IPCOMPSTAT_INC(ipcomps_##name); \
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} while (0)
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#ifdef INET
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static void ipsec4_common_ctlinput(int, struct sockaddr *, void *, int);
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#endif
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/*
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* ipsec_common_input gets called when an IPsec-protected packet
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* is received by IPv4 or IPv6. Its job is to find the right SA
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* and call the appropriate transform. The transform callback
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* takes care of further processing (like ingress filtering).
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*/
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static int
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ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto)
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{
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union sockaddr_union dst_address;
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struct secasvar *sav;
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u_int32_t spi;
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int error;
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#ifdef INET
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#ifdef IPSEC_NAT_T
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struct m_tag *tag;
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#endif
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#endif
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IPSEC_ISTAT(sproto, input);
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IPSEC_ASSERT(m != NULL, ("null packet"));
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IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
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sproto == IPPROTO_IPCOMP,
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("unexpected security protocol %u", sproto));
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if ((sproto == IPPROTO_ESP && !V_esp_enable) ||
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(sproto == IPPROTO_AH && !V_ah_enable) ||
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(sproto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
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m_freem(m);
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IPSEC_ISTAT(sproto, pdrops);
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return EOPNOTSUPP;
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}
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if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) {
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m_freem(m);
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IPSEC_ISTAT(sproto, hdrops);
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DPRINTF(("%s: packet too small\n", __func__));
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return EINVAL;
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}
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/* Retrieve the SPI from the relevant IPsec header */
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if (sproto == IPPROTO_ESP)
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m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi);
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else if (sproto == IPPROTO_AH)
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m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t),
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(caddr_t) &spi);
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else if (sproto == IPPROTO_IPCOMP) {
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u_int16_t cpi;
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m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t),
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(caddr_t) &cpi);
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spi = ntohl(htons(cpi));
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}
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/*
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* Find the SA and (indirectly) call the appropriate
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* kernel crypto routine. The resulting mbuf chain is a valid
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* IP packet ready to go through input processing.
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*/
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bzero(&dst_address, sizeof (dst_address));
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dst_address.sa.sa_family = af;
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switch (af) {
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#ifdef INET
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case AF_INET:
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dst_address.sin.sin_len = sizeof(struct sockaddr_in);
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m_copydata(m, offsetof(struct ip, ip_dst),
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sizeof(struct in_addr),
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(caddr_t) &dst_address.sin.sin_addr);
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#ifdef IPSEC_NAT_T
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/* Find the source port for NAT-T; see udp*_espdecap. */
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tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL);
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if (tag != NULL)
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dst_address.sin.sin_port = ((u_int16_t *)(tag + 1))[1];
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#endif /* IPSEC_NAT_T */
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break;
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#endif /* INET */
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#ifdef INET6
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case AF_INET6:
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dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6);
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m_copydata(m, offsetof(struct ip6_hdr, ip6_dst),
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sizeof(struct in6_addr),
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(caddr_t) &dst_address.sin6.sin6_addr);
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break;
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#endif /* INET6 */
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default:
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DPRINTF(("%s: unsupported protocol family %u\n", __func__, af));
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m_freem(m);
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IPSEC_ISTAT(sproto, nopf);
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return EPFNOSUPPORT;
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}
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/* NB: only pass dst since key_allocsa follows RFC2401 */
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sav = KEY_ALLOCSA(&dst_address, sproto, spi);
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if (sav == NULL) {
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DPRINTF(("%s: no key association found for SA %s/%08lx/%u\n",
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__func__, ipsec_address(&dst_address),
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(u_long) ntohl(spi), sproto));
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IPSEC_ISTAT(sproto, notdb);
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m_freem(m);
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return ENOENT;
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}
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if (sav->tdb_xform == NULL) {
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DPRINTF(("%s: attempted to use uninitialized SA %s/%08lx/%u\n",
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__func__, ipsec_address(&dst_address),
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(u_long) ntohl(spi), sproto));
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IPSEC_ISTAT(sproto, noxform);
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KEY_FREESAV(&sav);
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m_freem(m);
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return ENXIO;
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}
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/*
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* Call appropriate transform and return -- callback takes care of
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* everything else.
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*/
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error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff);
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KEY_FREESAV(&sav);
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return error;
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}
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#ifdef INET
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/*
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* Common input handler for IPv4 AH, ESP, and IPCOMP.
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*/
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int
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ipsec4_common_input(struct mbuf *m, ...)
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{
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va_list ap;
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int off, nxt;
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va_start(ap, m);
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off = va_arg(ap, int);
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nxt = va_arg(ap, int);
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va_end(ap);
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return ipsec_common_input(m, off, offsetof(struct ip, ip_p),
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AF_INET, nxt);
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}
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int
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ah4_input(struct mbuf **mp, int *offp, int proto)
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{
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struct mbuf *m;
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int off;
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m = *mp;
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off = *offp;
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*mp = NULL;
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ipsec4_common_input(m, off, IPPROTO_AH);
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return (IPPROTO_DONE);
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}
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void
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ah4_ctlinput(int cmd, struct sockaddr *sa, void *v)
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{
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if (sa->sa_family == AF_INET &&
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sa->sa_len == sizeof(struct sockaddr_in))
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ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_AH);
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}
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int
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esp4_input(struct mbuf **mp, int *offp, int proto)
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{
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struct mbuf *m;
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int off;
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m = *mp;
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off = *offp;
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mp = NULL;
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ipsec4_common_input(m, off, IPPROTO_ESP);
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return (IPPROTO_DONE);
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}
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void
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esp4_ctlinput(int cmd, struct sockaddr *sa, void *v)
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{
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if (sa->sa_family == AF_INET &&
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sa->sa_len == sizeof(struct sockaddr_in))
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ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_ESP);
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}
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int
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ipcomp4_input(struct mbuf **mp, int *offp, int proto)
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{
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struct mbuf *m;
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int off;
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m = *mp;
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off = *offp;
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mp = NULL;
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ipsec4_common_input(m, off, IPPROTO_IPCOMP);
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return (IPPROTO_DONE);
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}
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/*
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* IPsec input callback for INET protocols.
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* This routine is called as the transform callback.
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* Takes care of filtering and other sanity checks on
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* the processed packet.
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*/
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int
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ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip,
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int protoff)
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{
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int prot, af, sproto, isr_prot;
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struct ip *ip;
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struct m_tag *mtag;
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struct tdb_ident *tdbi;
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struct secasindex *saidx;
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int error;
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#ifdef INET6
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#ifdef notyet
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char ip6buf[INET6_ADDRSTRLEN];
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#endif
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#endif
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IPSEC_ASSERT(m != NULL, ("null mbuf"));
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IPSEC_ASSERT(sav != NULL, ("null SA"));
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IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
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saidx = &sav->sah->saidx;
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af = saidx->dst.sa.sa_family;
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IPSEC_ASSERT(af == AF_INET, ("unexpected af %u", af));
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sproto = saidx->proto;
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IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
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sproto == IPPROTO_IPCOMP,
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("unexpected security protocol %u", sproto));
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/* Sanity check */
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if (m == NULL) {
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DPRINTF(("%s: null mbuf", __func__));
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IPSEC_ISTAT(sproto, badkcr);
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KEY_FREESAV(&sav);
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return EINVAL;
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}
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if (skip != 0) {
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/*
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* Fix IPv4 header
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* XXXGL: do we need this entire block?
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*/
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if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) {
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DPRINTF(("%s: processing failed for SA %s/%08lx\n",
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__func__, ipsec_address(&sav->sah->saidx.dst),
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(u_long) ntohl(sav->spi)));
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IPSEC_ISTAT(sproto, hdrops);
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error = ENOBUFS;
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goto bad;
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}
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ip = mtod(m, struct ip *);
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ip->ip_len = htons(m->m_pkthdr.len);
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ip->ip_sum = 0;
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ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
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} else {
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ip = mtod(m, struct ip *);
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}
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prot = ip->ip_p;
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#ifdef DEV_ENC
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if_inc_counter(encif, IFCOUNTER_IPACKETS, 1);
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if_inc_counter(encif, IFCOUNTER_IBYTES, m->m_pkthdr.len);
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/* Pass the mbuf to enc0 for bpf and pfil. */
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ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_BEFORE);
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if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
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return (error);
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#endif /* DEV_ENC */
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/* IP-in-IP encapsulation */
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if (prot == IPPROTO_IPIP &&
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saidx->mode != IPSEC_MODE_TRANSPORT) {
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if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
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IPSEC_ISTAT(sproto, hdrops);
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error = EINVAL;
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goto bad;
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}
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/* enc0: strip outer IPv4 header */
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m_striphdr(m, 0, ip->ip_hl << 2);
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#ifdef notyet
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/* XXX PROXY address isn't recorded in SAH */
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/*
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* Check that the inner source address is the same as
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* the proxy address, if available.
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*/
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if ((saidx->proxy.sa.sa_family == AF_INET &&
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saidx->proxy.sin.sin_addr.s_addr !=
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INADDR_ANY &&
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ipn.ip_src.s_addr !=
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saidx->proxy.sin.sin_addr.s_addr) ||
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(saidx->proxy.sa.sa_family != AF_INET &&
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saidx->proxy.sa.sa_family != 0)) {
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DPRINTF(("%s: inner source address %s doesn't "
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"correspond to expected proxy source %s, "
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"SA %s/%08lx\n", __func__,
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inet_ntoa4(ipn.ip_src),
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ipsp_address(saidx->proxy),
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ipsp_address(saidx->dst),
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(u_long) ntohl(sav->spi)));
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IPSEC_ISTAT(sproto, pdrops);
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error = EACCES;
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goto bad;
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}
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#endif /* notyet */
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}
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#ifdef INET6
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/* IPv6-in-IP encapsulation. */
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else if (prot == IPPROTO_IPV6 &&
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saidx->mode != IPSEC_MODE_TRANSPORT) {
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if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
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IPSEC_ISTAT(sproto, hdrops);
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error = EINVAL;
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goto bad;
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}
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/* enc0: strip IPv4 header, keep IPv6 header only */
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m_striphdr(m, 0, ip->ip_hl << 2);
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#ifdef notyet
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/*
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* Check that the inner source address is the same as
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* the proxy address, if available.
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*/
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if ((saidx->proxy.sa.sa_family == AF_INET6 &&
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!IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
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!IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
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&saidx->proxy.sin6.sin6_addr)) ||
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(saidx->proxy.sa.sa_family != AF_INET6 &&
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saidx->proxy.sa.sa_family != 0)) {
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DPRINTF(("%s: inner source address %s doesn't "
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"correspond to expected proxy source %s, "
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"SA %s/%08lx\n", __func__,
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ip6_sprintf(ip6buf, &ip6n.ip6_src),
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ipsec_address(&saidx->proxy),
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ipsec_address(&saidx->dst),
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(u_long) ntohl(sav->spi)));
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IPSEC_ISTAT(sproto, pdrops);
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error = EACCES;
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goto bad;
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}
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#endif /* notyet */
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}
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#endif /* INET6 */
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else if (prot != IPPROTO_IPV6 && saidx->mode == IPSEC_MODE_ANY) {
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/*
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* When mode is wildcard, inner protocol is IPv6 and
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* we have no INET6 support - drop this packet a bit later.
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* In other cases we assume transport mode and outer
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* header was already stripped in xform_xxx_cb.
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*/
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prot = IPPROTO_IPIP;
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}
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/*
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* Record what we've done to the packet (under what SA it was
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* processed).
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*/
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if (sproto != IPPROTO_IPCOMP) {
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mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
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sizeof(struct tdb_ident), M_NOWAIT);
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if (mtag == NULL) {
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DPRINTF(("%s: failed to get tag\n", __func__));
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IPSEC_ISTAT(sproto, hdrops);
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error = ENOMEM;
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goto bad;
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}
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tdbi = (struct tdb_ident *)(mtag + 1);
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bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len);
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tdbi->proto = sproto;
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tdbi->spi = sav->spi;
|
|
/* Cache those two for enc(4) in xform_ipip. */
|
|
tdbi->alg_auth = sav->alg_auth;
|
|
tdbi->alg_enc = sav->alg_enc;
|
|
|
|
m_tag_prepend(m, mtag);
|
|
}
|
|
|
|
key_sa_recordxfer(sav, m); /* record data transfer */
|
|
|
|
/*
|
|
* In transport mode requeue decrypted mbuf back to IPv4 protocol
|
|
* handler. This is necessary to correctly expose rcvif.
|
|
*/
|
|
if (saidx->mode == IPSEC_MODE_TRANSPORT)
|
|
prot = IPPROTO_IPIP;
|
|
#ifdef DEV_ENC
|
|
/*
|
|
* Pass the mbuf to enc0 for bpf and pfil.
|
|
*/
|
|
if (prot == IPPROTO_IPIP)
|
|
ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER);
|
|
#ifdef INET6
|
|
if (prot == IPPROTO_IPV6)
|
|
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER);
|
|
#endif
|
|
|
|
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0)
|
|
return (error);
|
|
#endif /* DEV_ENC */
|
|
|
|
/*
|
|
* Re-dispatch via software interrupt.
|
|
*/
|
|
|
|
switch (prot) {
|
|
case IPPROTO_IPIP:
|
|
isr_prot = NETISR_IP;
|
|
break;
|
|
#ifdef INET6
|
|
case IPPROTO_IPV6:
|
|
isr_prot = NETISR_IPV6;
|
|
break;
|
|
#endif
|
|
default:
|
|
DPRINTF(("%s: cannot handle inner ip proto %d\n",
|
|
__func__, prot));
|
|
IPSEC_ISTAT(sproto, nopf);
|
|
error = EPFNOSUPPORT;
|
|
goto bad;
|
|
}
|
|
|
|
error = netisr_queue_src(isr_prot, (uintptr_t)sav->spi, m);
|
|
if (error) {
|
|
IPSEC_ISTAT(sproto, qfull);
|
|
DPRINTF(("%s: queue full; proto %u packet dropped\n",
|
|
__func__, sproto));
|
|
return error;
|
|
}
|
|
return 0;
|
|
bad:
|
|
m_freem(m);
|
|
return error;
|
|
}
|
|
|
|
void
|
|
ipsec4_common_ctlinput(int cmd, struct sockaddr *sa, void *v, int proto)
|
|
{
|
|
/* XXX nothing just yet */
|
|
}
|
|
#endif /* INET */
|
|
|
|
#ifdef INET6
|
|
/* IPv6 AH wrapper. */
|
|
int
|
|
ipsec6_common_input(struct mbuf **mp, int *offp, int proto)
|
|
{
|
|
int l = 0;
|
|
int protoff;
|
|
struct ip6_ext ip6e;
|
|
|
|
if (*offp < sizeof(struct ip6_hdr)) {
|
|
DPRINTF(("%s: bad offset %u\n", __func__, *offp));
|
|
return IPPROTO_DONE;
|
|
} else if (*offp == sizeof(struct ip6_hdr)) {
|
|
protoff = offsetof(struct ip6_hdr, ip6_nxt);
|
|
} else {
|
|
/* Chase down the header chain... */
|
|
protoff = sizeof(struct ip6_hdr);
|
|
|
|
do {
|
|
protoff += l;
|
|
m_copydata(*mp, protoff, sizeof(ip6e),
|
|
(caddr_t) &ip6e);
|
|
|
|
if (ip6e.ip6e_nxt == IPPROTO_AH)
|
|
l = (ip6e.ip6e_len + 2) << 2;
|
|
else
|
|
l = (ip6e.ip6e_len + 1) << 3;
|
|
IPSEC_ASSERT(l > 0, ("l went zero or negative"));
|
|
} while (protoff + l < *offp);
|
|
|
|
/* Malformed packet check */
|
|
if (protoff + l != *offp) {
|
|
DPRINTF(("%s: bad packet header chain, protoff %u, "
|
|
"l %u, off %u\n", __func__, protoff, l, *offp));
|
|
IPSEC_ISTAT(proto, hdrops);
|
|
m_freem(*mp);
|
|
*mp = NULL;
|
|
return IPPROTO_DONE;
|
|
}
|
|
protoff += offsetof(struct ip6_ext, ip6e_nxt);
|
|
}
|
|
(void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto);
|
|
return IPPROTO_DONE;
|
|
}
|
|
|
|
/*
|
|
* IPsec input callback, called by the transform callback. Takes care of
|
|
* filtering and other sanity checks on the processed packet.
|
|
*/
|
|
int
|
|
ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip,
|
|
int protoff)
|
|
{
|
|
int prot, af, sproto;
|
|
struct ip6_hdr *ip6;
|
|
struct m_tag *mtag;
|
|
struct tdb_ident *tdbi;
|
|
struct secasindex *saidx;
|
|
int nxt;
|
|
u_int8_t nxt8;
|
|
int error, nest;
|
|
#ifdef notyet
|
|
char ip6buf[INET6_ADDRSTRLEN];
|
|
#endif
|
|
|
|
IPSEC_ASSERT(m != NULL, ("null mbuf"));
|
|
IPSEC_ASSERT(sav != NULL, ("null SA"));
|
|
IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
|
|
saidx = &sav->sah->saidx;
|
|
af = saidx->dst.sa.sa_family;
|
|
IPSEC_ASSERT(af == AF_INET6, ("unexpected af %u", af));
|
|
sproto = saidx->proto;
|
|
IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
|
|
sproto == IPPROTO_IPCOMP,
|
|
("unexpected security protocol %u", sproto));
|
|
|
|
/* Sanity check */
|
|
if (m == NULL) {
|
|
DPRINTF(("%s: null mbuf", __func__));
|
|
IPSEC_ISTAT(sproto, badkcr);
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
|
|
/* Fix IPv6 header */
|
|
if (m->m_len < sizeof(struct ip6_hdr) &&
|
|
(m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
|
|
|
|
DPRINTF(("%s: processing failed for SA %s/%08lx\n",
|
|
__func__, ipsec_address(&sav->sah->saidx.dst),
|
|
(u_long) ntohl(sav->spi)));
|
|
|
|
IPSEC_ISTAT(sproto, hdrops);
|
|
error = EACCES;
|
|
goto bad;
|
|
}
|
|
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
|
|
|
|
/* Save protocol */
|
|
m_copydata(m, protoff, 1, &nxt8);
|
|
prot = nxt8;
|
|
|
|
#ifdef DEV_ENC
|
|
if_inc_counter(encif, IFCOUNTER_IPACKETS, 1);
|
|
if_inc_counter(encif, IFCOUNTER_IBYTES, m->m_pkthdr.len);
|
|
|
|
/* Pass the mbuf to enc0 for bpf and pfil. */
|
|
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_BEFORE);
|
|
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
|
|
return (error);
|
|
#endif /* DEV_ENC */
|
|
|
|
/* IPv6-in-IP encapsulation */
|
|
if (prot == IPPROTO_IPV6 &&
|
|
saidx->mode != IPSEC_MODE_TRANSPORT) {
|
|
if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
|
|
IPSEC_ISTAT(sproto, hdrops);
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
/* ip6n will now contain the inner IPv6 header. */
|
|
m_striphdr(m, 0, skip);
|
|
skip = 0;
|
|
#ifdef notyet
|
|
/*
|
|
* Check that the inner source address is the same as
|
|
* the proxy address, if available.
|
|
*/
|
|
if ((saidx->proxy.sa.sa_family == AF_INET6 &&
|
|
!IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
|
|
!IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
|
|
&saidx->proxy.sin6.sin6_addr)) ||
|
|
(saidx->proxy.sa.sa_family != AF_INET6 &&
|
|
saidx->proxy.sa.sa_family != 0)) {
|
|
|
|
DPRINTF(("%s: inner source address %s doesn't "
|
|
"correspond to expected proxy source %s, "
|
|
"SA %s/%08lx\n", __func__,
|
|
ip6_sprintf(ip6buf, &ip6n.ip6_src),
|
|
ipsec_address(&saidx->proxy),
|
|
ipsec_address(&saidx->dst),
|
|
(u_long) ntohl(sav->spi)));
|
|
|
|
IPSEC_ISTAT(sproto, pdrops);
|
|
error = EACCES;
|
|
goto bad;
|
|
}
|
|
#endif /* notyet */
|
|
}
|
|
#ifdef INET
|
|
/* IP-in-IP encapsulation */
|
|
else if (prot == IPPROTO_IPIP &&
|
|
saidx->mode != IPSEC_MODE_TRANSPORT) {
|
|
if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
|
|
IPSEC_ISTAT(sproto, hdrops);
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
/* ipn will now contain the inner IPv4 header */
|
|
m_striphdr(m, 0, skip);
|
|
skip = 0;
|
|
#ifdef notyet
|
|
/*
|
|
* Check that the inner source address is the same as
|
|
* the proxy address, if available.
|
|
*/
|
|
if ((saidx->proxy.sa.sa_family == AF_INET &&
|
|
saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY &&
|
|
ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) ||
|
|
(saidx->proxy.sa.sa_family != AF_INET &&
|
|
saidx->proxy.sa.sa_family != 0)) {
|
|
|
|
DPRINTF(("%s: inner source address %s doesn't "
|
|
"correspond to expected proxy source %s, "
|
|
"SA %s/%08lx\n", __func__,
|
|
inet_ntoa4(ipn.ip_src),
|
|
ipsec_address(&saidx->proxy),
|
|
ipsec_address(&saidx->dst),
|
|
(u_long) ntohl(sav->spi)));
|
|
|
|
IPSEC_ISTAT(sproto, pdrops);
|
|
error = EACCES;
|
|
goto bad;
|
|
}
|
|
#endif /* notyet */
|
|
}
|
|
#endif /* INET */
|
|
else {
|
|
prot = IPPROTO_IPV6; /* for correct BPF processing */
|
|
}
|
|
|
|
/*
|
|
* Record what we've done to the packet (under what SA it was
|
|
* processed).
|
|
*/
|
|
if (sproto != IPPROTO_IPCOMP) {
|
|
mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
|
|
sizeof(struct tdb_ident), M_NOWAIT);
|
|
if (mtag == NULL) {
|
|
DPRINTF(("%s: failed to get tag\n", __func__));
|
|
IPSEC_ISTAT(sproto, hdrops);
|
|
error = ENOMEM;
|
|
goto bad;
|
|
}
|
|
|
|
tdbi = (struct tdb_ident *)(mtag + 1);
|
|
bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union));
|
|
tdbi->proto = sproto;
|
|
tdbi->spi = sav->spi;
|
|
/* Cache those two for enc(4) in xform_ipip. */
|
|
tdbi->alg_auth = sav->alg_auth;
|
|
tdbi->alg_enc = sav->alg_enc;
|
|
|
|
m_tag_prepend(m, mtag);
|
|
}
|
|
|
|
key_sa_recordxfer(sav, m);
|
|
|
|
#ifdef DEV_ENC
|
|
/*
|
|
* Pass the mbuf to enc0 for bpf and pfil.
|
|
*/
|
|
#ifdef INET
|
|
if (prot == IPPROTO_IPIP)
|
|
ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER);
|
|
#endif
|
|
if (prot == IPPROTO_IPV6)
|
|
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER);
|
|
|
|
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0)
|
|
return (error);
|
|
#endif /* DEV_ENC */
|
|
/*
|
|
* See the end of ip6_input for this logic.
|
|
* IPPROTO_IPV[46] case will be processed just like other ones
|
|
*/
|
|
nest = 0;
|
|
nxt = nxt8;
|
|
while (nxt != IPPROTO_DONE) {
|
|
if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
|
|
IP6STAT_INC(ip6s_toomanyhdr);
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
|
|
/*
|
|
* Protection against faulty packet - there should be
|
|
* more sanity checks in header chain processing.
|
|
*/
|
|
if (m->m_pkthdr.len < skip) {
|
|
IP6STAT_INC(ip6s_tooshort);
|
|
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
/*
|
|
* Enforce IPsec policy checking if we are seeing last header.
|
|
* note that we do not visit this with protocols with pcb layer
|
|
* code - like udp/tcp/raw ip.
|
|
*/
|
|
if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
|
|
ipsec6_in_reject(m, NULL)) {
|
|
error = EINVAL;
|
|
goto bad;
|
|
}
|
|
nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt);
|
|
}
|
|
return 0;
|
|
bad:
|
|
if (m)
|
|
m_freem(m);
|
|
return error;
|
|
}
|
|
|
|
void
|
|
esp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
|
|
{
|
|
struct ip6ctlparam *ip6cp = NULL;
|
|
struct mbuf *m = NULL;
|
|
struct ip6_hdr *ip6;
|
|
int off;
|
|
|
|
if (sa->sa_family != AF_INET6 ||
|
|
sa->sa_len != sizeof(struct sockaddr_in6))
|
|
return;
|
|
if ((unsigned)cmd >= PRC_NCMDS)
|
|
return;
|
|
|
|
/* if the parameter is from icmp6, decode it. */
|
|
if (d != NULL) {
|
|
ip6cp = (struct ip6ctlparam *)d;
|
|
m = ip6cp->ip6c_m;
|
|
ip6 = ip6cp->ip6c_ip6;
|
|
off = ip6cp->ip6c_off;
|
|
} else {
|
|
m = NULL;
|
|
ip6 = NULL;
|
|
off = 0; /* calm gcc */
|
|
}
|
|
|
|
if (ip6 != NULL) {
|
|
|
|
struct ip6ctlparam ip6cp1;
|
|
|
|
/*
|
|
* Notify the error to all possible sockets via pfctlinput2.
|
|
* Since the upper layer information (such as protocol type,
|
|
* source and destination ports) is embedded in the encrypted
|
|
* data and might have been cut, we can't directly call
|
|
* an upper layer ctlinput function. However, the pcbnotify
|
|
* function will consider source and destination addresses
|
|
* as well as the flow info value, and may be able to find
|
|
* some PCB that should be notified.
|
|
* Although pfctlinput2 will call esp6_ctlinput(), there is
|
|
* no possibility of an infinite loop of function calls,
|
|
* because we don't pass the inner IPv6 header.
|
|
*/
|
|
bzero(&ip6cp1, sizeof(ip6cp1));
|
|
ip6cp1.ip6c_src = ip6cp->ip6c_src;
|
|
pfctlinput2(cmd, sa, (void *)&ip6cp1);
|
|
|
|
/*
|
|
* Then go to special cases that need ESP header information.
|
|
* XXX: We assume that when ip6 is non NULL,
|
|
* M and OFF are valid.
|
|
*/
|
|
|
|
if (cmd == PRC_MSGSIZE) {
|
|
struct secasvar *sav;
|
|
u_int32_t spi;
|
|
int valid;
|
|
|
|
/* check header length before using m_copydata */
|
|
if (m->m_pkthdr.len < off + sizeof (struct esp))
|
|
return;
|
|
m_copydata(m, off + offsetof(struct esp, esp_spi),
|
|
sizeof(u_int32_t), (caddr_t) &spi);
|
|
/*
|
|
* Check to see if we have a valid SA corresponding to
|
|
* the address in the ICMP message payload.
|
|
*/
|
|
sav = KEY_ALLOCSA((union sockaddr_union *)sa,
|
|
IPPROTO_ESP, spi);
|
|
valid = (sav != NULL);
|
|
if (sav)
|
|
KEY_FREESAV(&sav);
|
|
|
|
/* XXX Further validation? */
|
|
|
|
/*
|
|
* Depending on whether the SA is "valid" and
|
|
* routing table size (mtudisc_{hi,lo}wat), we will:
|
|
* - recalcurate the new MTU and create the
|
|
* corresponding routing entry, or
|
|
* - ignore the MTU change notification.
|
|
*/
|
|
icmp6_mtudisc_update(ip6cp, valid);
|
|
}
|
|
} else {
|
|
/* we normally notify any pcb here */
|
|
}
|
|
}
|
|
#endif /* INET6 */
|