a28b277a9f
Instead requeue mbuf back to IPv4 protocol handler. If there is one extra IP-IP encapsulation, it will be handled with tunneling interface. And thus proper interface will be exposed into mbuf's rcvif. Also, tcpdump that listens on tunneling interface will see packets in both directions. Sponsored by: Yandex LLC
947 lines
24 KiB
C
947 lines
24 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/route.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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|
|
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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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|
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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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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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}
|
|
|
|
int
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ipcomp4_input(struct mbuf **mp, int *offp, int proto)
|
|
{
|
|
struct mbuf *m;
|
|
int off;
|
|
|
|
m = *mp;
|
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off = *offp;
|
|
mp = NULL;
|
|
|
|
ipsec4_common_input(m, off, IPPROTO_IPCOMP);
|
|
return (IPPROTO_DONE);
|
|
}
|
|
|
|
/*
|
|
* IPsec input callback for INET protocols.
|
|
* This routine is called as the transform callback.
|
|
* Takes care of filtering and other sanity checks on
|
|
* the processed packet.
|
|
*/
|
|
int
|
|
ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav,
|
|
int skip, int protoff, struct m_tag *mt)
|
|
{
|
|
int prot, af, sproto, isr_prot;
|
|
struct ip *ip;
|
|
struct m_tag *mtag;
|
|
struct tdb_ident *tdbi;
|
|
struct secasindex *saidx;
|
|
int error;
|
|
#ifdef INET6
|
|
#ifdef notyet
|
|
char ip6buf[INET6_ADDRSTRLEN];
|
|
#endif
|
|
#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_INET, ("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);
|
|
KEY_FREESAV(&sav);
|
|
return EINVAL;
|
|
}
|
|
|
|
if (skip != 0) {
|
|
/*
|
|
* Fix IPv4 header
|
|
* XXXGL: do we need this entire block?
|
|
*/
|
|
if (m->m_len < skip && (m = m_pullup(m, skip)) == 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 = ENOBUFS;
|
|
goto bad;
|
|
}
|
|
|
|
ip = mtod(m, struct ip *);
|
|
ip->ip_len = htons(m->m_pkthdr.len);
|
|
ip->ip_sum = 0;
|
|
ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
|
|
} else {
|
|
ip = mtod(m, struct ip *);
|
|
}
|
|
prot = ip->ip_p;
|
|
|
|
#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. We will filter the IPIP
|
|
* packet later after it has been decapsulated.
|
|
*/
|
|
ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_BEFORE);
|
|
|
|
if (prot != IPPROTO_IPIP)
|
|
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
|
|
return (error);
|
|
#endif /* DEV_ENC */
|
|
|
|
/* IP-in-IP encapsulation */
|
|
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;
|
|
}
|
|
/* enc0: strip outer IPv4 header */
|
|
m_striphdr(m, 0, ip->ip_hl << 2);
|
|
|
|
#ifdef notyet
|
|
/* XXX PROXY address isn't recorded in SAH */
|
|
/*
|
|
* 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),
|
|
ipsp_address(saidx->proxy),
|
|
ipsp_address(saidx->dst),
|
|
(u_long) ntohl(sav->spi)));
|
|
|
|
IPSEC_ISTAT(sproto, pdrops);
|
|
error = EACCES;
|
|
goto bad;
|
|
}
|
|
#endif /* notyet */
|
|
}
|
|
#ifdef INET6
|
|
/* 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;
|
|
}
|
|
/* enc0: strip IPv4 header, keep IPv6 header only */
|
|
m_striphdr(m, 0, ip->ip_hl << 2);
|
|
#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 */
|
|
}
|
|
#endif /* INET6 */
|
|
|
|
/*
|
|
* Record what we've done to the packet (under what SA it was
|
|
* processed). If we've been passed an mtag, it means the packet
|
|
* was already processed by an ethernet/crypto combo card and
|
|
* thus has a tag attached with all the right information, but
|
|
* with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to
|
|
* PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type.
|
|
*/
|
|
if (mt == NULL && 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, saidx->dst.sa.sa_len);
|
|
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);
|
|
} else if (mt != NULL) {
|
|
mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE;
|
|
/* XXX do we need to mark m_flags??? */
|
|
}
|
|
|
|
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,
|
|
struct m_tag *mt)
|
|
{
|
|
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 */
|
|
prot = 0;
|
|
m_copydata(m, protoff, 1, (unsigned char *) &prot);
|
|
|
|
#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. We will filter the IPIP
|
|
* packet later after it has been decapsulated.
|
|
*/
|
|
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_BEFORE);
|
|
|
|
/* XXX-BZ does not make sense. */
|
|
if (prot != IPPROTO_IPIP)
|
|
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
|
|
return (error);
|
|
#endif /* DEV_ENC */
|
|
|
|
#ifdef INET
|
|
/* IP-in-IP encapsulation */
|
|
if (prot == IPPROTO_IPIP) {
|
|
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 */
|
|
/* IPv6-in-IP encapsulation */
|
|
if (prot == IPPROTO_IPV6) {
|
|
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 */
|
|
}
|
|
|
|
/*
|
|
* Record what we've done to the packet (under what SA it was
|
|
* processed). If we've been passed an mtag, it means the packet
|
|
* was already processed by an ethernet/crypto combo card and
|
|
* thus has a tag attached with all the right information, but
|
|
* with a PACKET_TAG_IPSEC_IN_CRYPTO_DONE as opposed to
|
|
* PACKET_TAG_IPSEC_IN_DONE type; in that case, just change the type.
|
|
*/
|
|
if (mt == NULL && 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);
|
|
} else {
|
|
if (mt != NULL)
|
|
mt->m_tag_id = PACKET_TAG_IPSEC_IN_DONE;
|
|
/* XXX do we need to mark m_flags??? */
|
|
}
|
|
|
|
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 */
|
|
/* Retrieve new protocol */
|
|
/* We have stripped the IP6 header from the mbuf, we have to use the backuped proto value instead */
|
|
nxt8 = prot;
|
|
|
|
/*
|
|
* 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 */
|