981 lines
24 KiB
C
981 lines
24 KiB
C
/* $FreeBSD$ */
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/* $KAME: ah_input.c,v 1.29 2000/05/29 08:33:53 itojun Exp $ */
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/*
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* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. Neither the name of the project nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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/*
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* RFC1826/2402 authentication header.
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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 <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/time.h>
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#include <sys/syslog.h>
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#include <net/if.h>
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#include <net/route.h>
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#include <net/netisr.h>
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#include <machine/cpu.h>
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#include <netinet/in.h>
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#include <netinet/in_systm.h>
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#include <netinet/in_var.h>
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#include <netinet/ip.h>
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#include <netinet/ip_var.h>
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#include <netinet/ip_ecn.h>
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#ifdef INET6
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#include <netinet6/ip6_ecn.h>
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#endif
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#ifdef INET6
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#include <netinet/ip6.h>
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#include <netinet6/ip6_var.h>
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#include <netinet/icmp6.h>
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#endif
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#include <netinet6/ipsec.h>
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#ifdef INET6
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#include <netinet6/ipsec6.h>
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#endif
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#include <netinet6/ah.h>
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#ifdef INET6
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#include <netinet6/ah6.h>
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#endif
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#include <netkey/key.h>
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#include <netkey/keydb.h>
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#ifdef IPSEC_DEBUG
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#include <netkey/key_debug.h>
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#else
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#define KEYDEBUG(lev,arg)
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#endif
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#include <machine/stdarg.h>
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#include <net/net_osdep.h>
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#define IPLEN_FLIPPED
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#ifdef INET
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#include <netinet/ipprotosw.h>
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extern struct ipprotosw inetsw[];
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void
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#if __STDC__
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ah4_input(struct mbuf *m, ...)
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#else
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ah4_input(m, va_alist)
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struct mbuf *m;
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va_dcl
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#endif
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{
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struct ip *ip;
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struct ah *ah;
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u_int32_t spi;
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struct ah_algorithm *algo;
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size_t siz;
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size_t siz1;
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u_char *cksum;
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struct secasvar *sav = NULL;
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u_int16_t nxt;
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size_t hlen;
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int s;
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int off, proto;
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va_list ap;
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va_start(ap, m);
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off = va_arg(ap, int);
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proto = va_arg(ap, int);
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va_end(ap);
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#ifndef PULLDOWN_TEST
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if (m->m_len < off + sizeof(struct newah)) {
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m = m_pullup(m, off + sizeof(struct newah));
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if (!m) {
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ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;"
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"dropping the packet for simplicity\n"));
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ipsecstat.in_inval++;
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goto fail;
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}
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}
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ip = mtod(m, struct ip *);
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ah = (struct ah *)(((caddr_t)ip) + off);
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#else
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ip = mtod(m, struct ip *);
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IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah));
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if (ah == NULL) {
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ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;"
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"dropping the packet for simplicity\n"));
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ipsecstat.in_inval++;
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goto fail;
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}
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#endif
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nxt = ah->ah_nxt;
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#ifdef _IP_VHL
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hlen = IP_VHL_HL(ip->ip_vhl) << 2;
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#else
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hlen = ip->ip_hl << 2;
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#endif
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/* find the sassoc. */
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spi = ah->ah_spi;
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if ((sav = key_allocsa(AF_INET,
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(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
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IPPROTO_AH, spi)) == 0) {
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ipseclog((LOG_WARNING,
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"IPv4 AH input: no key association found for spi %u\n",
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(u_int32_t)ntohl(spi)));
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ipsecstat.in_nosa++;
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goto fail;
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}
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KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
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printf("DP ah4_input called to allocate SA:%p\n", sav));
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if (sav->state != SADB_SASTATE_MATURE
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&& sav->state != SADB_SASTATE_DYING) {
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ipseclog((LOG_DEBUG,
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"IPv4 AH input: non-mature/dying SA found for spi %u\n",
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(u_int32_t)ntohl(spi)));
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ipsecstat.in_badspi++;
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goto fail;
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}
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if (sav->alg_auth == SADB_AALG_NONE) {
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ipseclog((LOG_DEBUG, "IPv4 AH input: "
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"unspecified authentication algorithm for spi %u\n",
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(u_int32_t)ntohl(spi)));
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ipsecstat.in_badspi++;
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goto fail;
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}
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algo = &ah_algorithms[sav->alg_auth];
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siz = (*algo->sumsiz)(sav);
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siz1 = ((siz + 3) & ~(4 - 1));
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/*
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* sanity checks for header, 1.
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*/
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{
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int sizoff;
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sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
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/*
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* Here, we do not do "siz1 == siz". This is because the way
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* RFC240[34] section 2 is written. They do not require truncation
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* to 96 bits.
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* For example, Microsoft IPsec stack attaches 160 bits of
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* authentication data for both hmac-md5 and hmac-sha1. For hmac-sha1,
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* 32 bits of padding is attached.
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*
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* There are two downsides to this specification.
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* They have no real harm, however, they leave us fuzzy feeling.
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* - if we attach more than 96 bits of authentication data onto AH,
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* we will never notice about possible modification by rogue
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* intermediate nodes.
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* Since extra bits in AH checksum is never used, this constitutes
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* no real issue, however, it is wacky.
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* - even if the peer attaches big authentication data, we will never
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* notice the difference, since longer authentication data will just
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* work.
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*
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* We may need some clarification in the spec.
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*/
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if (siz1 < siz) {
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ipseclog((LOG_NOTICE, "sum length too short in IPv4 AH input "
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"(%lu, should be at least %lu): %s\n",
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(u_long)siz1, (u_long)siz,
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ipsec4_logpacketstr(ip, spi)));
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ipsecstat.in_inval++;
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goto fail;
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}
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if ((ah->ah_len << 2) - sizoff != siz1) {
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ipseclog((LOG_NOTICE, "sum length mismatch in IPv4 AH input "
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"(%d should be %lu): %s\n",
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(ah->ah_len << 2) - sizoff, (u_long)siz1,
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ipsec4_logpacketstr(ip, spi)));
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ipsecstat.in_inval++;
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goto fail;
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}
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#ifndef PULLDOWN_TEST
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if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) {
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m = m_pullup(m, off + sizeof(struct ah) + sizoff + siz1);
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if (!m) {
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ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n"));
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ipsecstat.in_inval++;
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goto fail;
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}
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ip = mtod(m, struct ip *);
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ah = (struct ah *)(((caddr_t)ip) + off);
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}
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#else
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IP6_EXTHDR_GET(ah, struct ah *, m, off,
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sizeof(struct ah) + sizoff + siz1);
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if (ah == NULL) {
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ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n"));
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ipsecstat.in_inval++;
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goto fail;
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}
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#endif
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}
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/*
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* check for sequence number.
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*/
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if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
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if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav))
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; /*okey*/
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else {
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ipsecstat.in_ahreplay++;
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ipseclog((LOG_WARNING,
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"replay packet in IPv4 AH input: %s %s\n",
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ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
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goto fail;
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}
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}
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/*
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* alright, it seems sane. now we are going to check the
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* cryptographic checksum.
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*/
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cksum = malloc(siz1, M_TEMP, M_NOWAIT);
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if (!cksum) {
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ipseclog((LOG_DEBUG, "IPv4 AH input: "
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"couldn't alloc temporary region for cksum\n"));
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ipsecstat.in_inval++;
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goto fail;
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}
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{
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#if 1
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/*
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* some of IP header fields are flipped to the host endian.
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* convert them back to network endian. VERY stupid.
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*/
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ip->ip_len = htons(ip->ip_len + hlen);
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ip->ip_id = htons(ip->ip_id);
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ip->ip_off = htons(ip->ip_off);
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#endif
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if (ah4_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) {
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free(cksum, M_TEMP);
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ipsecstat.in_inval++;
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goto fail;
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}
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ipsecstat.in_ahhist[sav->alg_auth]++;
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#if 1
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/*
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* flip them back.
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*/
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ip->ip_len = ntohs(ip->ip_len) - hlen;
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ip->ip_id = ntohs(ip->ip_id);
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ip->ip_off = ntohs(ip->ip_off);
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#endif
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}
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{
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caddr_t sumpos = NULL;
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if (sav->flags & SADB_X_EXT_OLD) {
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/* RFC 1826 */
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sumpos = (caddr_t)(ah + 1);
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} else {
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/* RFC 2402 */
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sumpos = (caddr_t)(((struct newah *)ah) + 1);
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}
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if (bcmp(sumpos, cksum, siz) != 0) {
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ipseclog((LOG_WARNING,
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"checksum mismatch in IPv4 AH input: %s %s\n",
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ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
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free(cksum, M_TEMP);
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ipsecstat.in_ahauthfail++;
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goto fail;
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}
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}
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free(cksum, M_TEMP);
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m->m_flags |= M_AUTHIPHDR;
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m->m_flags |= M_AUTHIPDGM;
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#if 0
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/*
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* looks okey, but we need more sanity check.
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* XXX should elaborate.
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*/
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if (ah->ah_nxt == IPPROTO_IPIP || ah->ah_nxt == IPPROTO_IP) {
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struct ip *nip;
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size_t sizoff;
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sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
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if (m->m_len < off + sizeof(struct ah) + sizoff + siz1 + hlen) {
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m = m_pullup(m, off + sizeof(struct ah)
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+ sizoff + siz1 + hlen);
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if (!m) {
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ipseclog((LOG_DEBUG,
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"IPv4 AH input: can't pullup\n"));
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ipsecstat.in_inval++;
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goto fail;
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}
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}
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nip = (struct ip *)((u_char *)(ah + 1) + sizoff + siz1);
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if (nip->ip_src.s_addr != ip->ip_src.s_addr
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|| nip->ip_dst.s_addr != ip->ip_dst.s_addr) {
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m->m_flags &= ~M_AUTHIPHDR;
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m->m_flags &= ~M_AUTHIPDGM;
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}
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}
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#ifdef INET6
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else if (ah->ah_nxt == IPPROTO_IPV6) {
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m->m_flags &= ~M_AUTHIPHDR;
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m->m_flags &= ~M_AUTHIPDGM;
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}
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#endif /*INET6*/
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#endif /*0*/
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if (m->m_flags & M_AUTHIPHDR
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&& m->m_flags & M_AUTHIPDGM) {
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#if 0
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ipseclog((LOG_DEBUG,
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"IPv4 AH input: authentication succeess\n"));
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#endif
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ipsecstat.in_ahauthsucc++;
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} else {
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ipseclog((LOG_WARNING,
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"authentication failed in IPv4 AH input: %s %s\n",
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ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
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ipsecstat.in_ahauthfail++;
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goto fail;
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}
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/*
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* update sequence number.
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*/
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if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
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if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) {
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ipsecstat.in_ahreplay++;
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goto fail;
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}
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}
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|
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/* was it transmitted over the IPsec tunnel SA? */
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if (ipsec4_tunnel_validate(ip, nxt, sav) && nxt == IPPROTO_IPV4) {
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/*
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* strip off all the headers that precedes AH.
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* IP xx AH IP' payload -> IP' payload
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*
|
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* XXX more sanity checks
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* XXX relationship with gif?
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*/
|
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size_t stripsiz = 0;
|
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u_int8_t tos;
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|
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tos = ip->ip_tos;
|
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if (sav->flags & SADB_X_EXT_OLD) {
|
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/* RFC 1826 */
|
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stripsiz = sizeof(struct ah) + siz1;
|
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} else {
|
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/* RFC 2402 */
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stripsiz = sizeof(struct newah) + siz1;
|
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}
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m_adj(m, off + stripsiz);
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if (m->m_len < sizeof(*ip)) {
|
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m = m_pullup(m, sizeof(*ip));
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if (!m) {
|
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ipsecstat.in_inval++;
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goto fail;
|
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}
|
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}
|
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ip = mtod(m, struct ip *);
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/* ECN consideration. */
|
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ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos);
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if (!key_checktunnelsanity(sav, AF_INET,
|
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(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
|
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ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch "
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"in IPv4 AH input: %s %s\n",
|
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ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
|
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ipsecstat.in_inval++;
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goto fail;
|
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}
|
|
|
|
#if 0 /* XXX should we call ipfw rather than ipsec_in_reject? */
|
|
/* drop it if it does not match the default policy */
|
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if (ipsec4_in_reject(m, NULL)) {
|
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ipsecstat.in_polvio++;
|
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goto fail;
|
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}
|
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#endif
|
|
|
|
#if 1
|
|
/*
|
|
* Should the inner packet be considered authentic?
|
|
* My current answer is: NO.
|
|
*
|
|
* host1 -- gw1 === gw2 -- host2
|
|
* In this case, gw2 can trust the authenticity of the
|
|
* outer packet, but NOT inner. Packet may be altered
|
|
* between host1 and gw1.
|
|
*
|
|
* host1 -- gw1 === host2
|
|
* This case falls into the same scenario as above.
|
|
*
|
|
* host1 === host2
|
|
* This case is the only case when we may be able to leave
|
|
* M_AUTHIPHDR and M_AUTHIPDGM set.
|
|
* However, if host1 is wrongly configured, and allows
|
|
* attacker to inject some packet with src=host1 and
|
|
* dst=host2, you are in risk.
|
|
*/
|
|
m->m_flags &= ~M_AUTHIPHDR;
|
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m->m_flags &= ~M_AUTHIPDGM;
|
|
#endif
|
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|
|
key_sa_recordxfer(sav, m);
|
|
|
|
s = splimp();
|
|
if (IF_QFULL(&ipintrq)) {
|
|
ipsecstat.in_inval++;
|
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splx(s);
|
|
goto fail;
|
|
}
|
|
IF_ENQUEUE(&ipintrq, m);
|
|
m = NULL;
|
|
schednetisr(NETISR_IP); /*can be skipped but to make sure*/
|
|
splx(s);
|
|
nxt = IPPROTO_DONE;
|
|
} else {
|
|
/*
|
|
* strip off AH.
|
|
*/
|
|
size_t stripsiz = 0;
|
|
|
|
if (sav->flags & SADB_X_EXT_OLD) {
|
|
/* RFC 1826 */
|
|
stripsiz = sizeof(struct ah) + siz1;
|
|
} else {
|
|
/* RFC 2402 */
|
|
stripsiz = sizeof(struct newah) + siz1;
|
|
}
|
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|
|
ip = mtod(m, struct ip *);
|
|
#ifndef PULLDOWN_TEST
|
|
/*
|
|
* We do deep-copy since KAME requires that
|
|
* the packet is placed in a single external mbuf.
|
|
*/
|
|
ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off);
|
|
m->m_data += stripsiz;
|
|
m->m_len -= stripsiz;
|
|
m->m_pkthdr.len -= stripsiz;
|
|
#else
|
|
/*
|
|
* even in m_pulldown case, we need to strip off AH so that
|
|
* we can compute checksum for multiple AH correctly.
|
|
*/
|
|
if (m->m_len >= stripsiz + off) {
|
|
ovbcopy((caddr_t)ip, ((caddr_t)ip) + stripsiz, off);
|
|
m->m_data += stripsiz;
|
|
m->m_len -= stripsiz;
|
|
m->m_pkthdr.len -= stripsiz;
|
|
} else {
|
|
/*
|
|
* this comes with no copy if the boundary is on
|
|
* cluster
|
|
*/
|
|
struct mbuf *n;
|
|
|
|
n = m_split(m, off, M_DONTWAIT);
|
|
if (n == NULL) {
|
|
/* m is retained by m_split */
|
|
goto fail;
|
|
}
|
|
m_adj(n, stripsiz);
|
|
m_cat(m, n);
|
|
/* m_cat does not update m_pkthdr.len */
|
|
m->m_pkthdr.len += n->m_pkthdr.len;
|
|
}
|
|
#endif
|
|
|
|
if (m->m_len < sizeof(*ip)) {
|
|
m = m_pullup(m, sizeof(*ip));
|
|
if (m == NULL) {
|
|
ipsecstat.in_inval++;
|
|
goto fail;
|
|
}
|
|
}
|
|
ip = mtod(m, struct ip *);
|
|
#ifdef IPLEN_FLIPPED
|
|
ip->ip_len = ip->ip_len - stripsiz;
|
|
#else
|
|
ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
|
|
#endif
|
|
ip->ip_p = nxt;
|
|
/* forget about IP hdr checksum, the check has already been passed */
|
|
|
|
key_sa_recordxfer(sav, m);
|
|
|
|
if (nxt != IPPROTO_DONE)
|
|
(*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt);
|
|
else
|
|
m_freem(m);
|
|
m = NULL;
|
|
}
|
|
|
|
if (sav) {
|
|
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
|
|
printf("DP ah4_input call free SA:%p\n", sav));
|
|
key_freesav(sav);
|
|
}
|
|
ipsecstat.in_success++;
|
|
return;
|
|
|
|
fail:
|
|
if (sav) {
|
|
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
|
|
printf("DP ah4_input call free SA:%p\n", sav));
|
|
key_freesav(sav);
|
|
}
|
|
if (m)
|
|
m_freem(m);
|
|
return;
|
|
}
|
|
#endif /* INET */
|
|
|
|
#ifdef INET6
|
|
int
|
|
ah6_input(mp, offp, proto)
|
|
struct mbuf **mp;
|
|
int *offp, proto;
|
|
{
|
|
struct mbuf *m = *mp;
|
|
int off = *offp;
|
|
struct ip6_hdr *ip6;
|
|
struct ah *ah;
|
|
u_int32_t spi;
|
|
struct ah_algorithm *algo;
|
|
size_t siz;
|
|
size_t siz1;
|
|
u_char *cksum;
|
|
struct secasvar *sav = NULL;
|
|
u_int16_t nxt;
|
|
int s;
|
|
|
|
#ifndef PULLDOWN_TEST
|
|
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), IPPROTO_DONE);
|
|
ah = (struct ah *)(mtod(m, caddr_t) + off);
|
|
#else
|
|
IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah));
|
|
if (ah == NULL) {
|
|
ipseclog((LOG_DEBUG, "IPv6 AH input: can't pullup\n"));
|
|
ipsecstat.in_inval++;
|
|
return IPPROTO_DONE;
|
|
}
|
|
#endif
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
nxt = ah->ah_nxt;
|
|
|
|
/* find the sassoc. */
|
|
spi = ah->ah_spi;
|
|
|
|
if (ntohs(ip6->ip6_plen) == 0) {
|
|
ipseclog((LOG_ERR, "IPv6 AH input: "
|
|
"AH with IPv6 jumbogram is not supported.\n"));
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
|
|
if ((sav = key_allocsa(AF_INET6,
|
|
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
|
|
IPPROTO_AH, spi)) == 0) {
|
|
ipseclog((LOG_WARNING,
|
|
"IPv6 AH input: no key association found for spi %u\n",
|
|
(u_int32_t)ntohl(spi)));
|
|
ipsec6stat.in_nosa++;
|
|
goto fail;
|
|
}
|
|
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
|
|
printf("DP ah6_input called to allocate SA:%p\n", sav));
|
|
if (sav->state != SADB_SASTATE_MATURE
|
|
&& sav->state != SADB_SASTATE_DYING) {
|
|
ipseclog((LOG_DEBUG,
|
|
"IPv6 AH input: non-mature/dying SA found for spi %u; ",
|
|
(u_int32_t)ntohl(spi)));
|
|
ipsec6stat.in_badspi++;
|
|
goto fail;
|
|
}
|
|
if (sav->alg_auth == SADB_AALG_NONE) {
|
|
ipseclog((LOG_DEBUG, "IPv6 AH input: "
|
|
"unspecified authentication algorithm for spi %u\n",
|
|
(u_int32_t)ntohl(spi)));
|
|
ipsec6stat.in_badspi++;
|
|
goto fail;
|
|
}
|
|
|
|
algo = &ah_algorithms[sav->alg_auth];
|
|
|
|
siz = (*algo->sumsiz)(sav);
|
|
siz1 = ((siz + 3) & ~(4 - 1));
|
|
|
|
/*
|
|
* sanity checks for header, 1.
|
|
*/
|
|
{
|
|
int sizoff;
|
|
|
|
sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
|
|
|
|
/*
|
|
* Here, we do not do "siz1 == siz". See ah4_input() for complete
|
|
* description.
|
|
*/
|
|
if (siz1 < siz) {
|
|
ipseclog((LOG_NOTICE, "sum length too short in IPv6 AH input "
|
|
"(%lu, should be at least %lu): %s\n",
|
|
(u_long)siz1, (u_long)siz,
|
|
ipsec6_logpacketstr(ip6, spi)));
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
if ((ah->ah_len << 2) - sizoff != siz1) {
|
|
ipseclog((LOG_NOTICE, "sum length mismatch in IPv6 AH input "
|
|
"(%d should be %lu): %s\n",
|
|
(ah->ah_len << 2) - sizoff, (u_long)siz1,
|
|
ipsec6_logpacketstr(ip6, spi)));
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
#ifndef PULLDOWN_TEST
|
|
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1, IPPROTO_DONE);
|
|
#else
|
|
IP6_EXTHDR_GET(ah, struct ah *, m, off,
|
|
sizeof(struct ah) + sizoff + siz1);
|
|
if (ah == NULL) {
|
|
ipseclog((LOG_NOTICE, "couldn't pullup gather IPv6 AH checksum part"));
|
|
ipsecstat.in_inval++;
|
|
m = NULL;
|
|
goto fail;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* check for sequence number.
|
|
*/
|
|
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
|
|
if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav))
|
|
; /*okey*/
|
|
else {
|
|
ipsec6stat.in_ahreplay++;
|
|
ipseclog((LOG_WARNING,
|
|
"replay packet in IPv6 AH input: %s %s\n",
|
|
ipsec6_logpacketstr(ip6, spi),
|
|
ipsec_logsastr(sav)));
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* alright, it seems sane. now we are going to check the
|
|
* cryptographic checksum.
|
|
*/
|
|
cksum = malloc(siz1, M_TEMP, M_NOWAIT);
|
|
if (!cksum) {
|
|
ipseclog((LOG_DEBUG, "IPv6 AH input: "
|
|
"couldn't alloc temporary region for cksum\n"));
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
|
|
if (ah6_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) {
|
|
free(cksum, M_TEMP);
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
ipsec6stat.in_ahhist[sav->alg_auth]++;
|
|
|
|
{
|
|
caddr_t sumpos = NULL;
|
|
|
|
if (sav->flags & SADB_X_EXT_OLD) {
|
|
/* RFC 1826 */
|
|
sumpos = (caddr_t)(ah + 1);
|
|
} else {
|
|
/* RFC 2402 */
|
|
sumpos = (caddr_t)(((struct newah *)ah) + 1);
|
|
}
|
|
|
|
if (bcmp(sumpos, cksum, siz) != 0) {
|
|
ipseclog((LOG_WARNING,
|
|
"checksum mismatch in IPv6 AH input: %s %s\n",
|
|
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
|
|
free(cksum, M_TEMP);
|
|
ipsec6stat.in_ahauthfail++;
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
free(cksum, M_TEMP);
|
|
|
|
m->m_flags |= M_AUTHIPHDR;
|
|
m->m_flags |= M_AUTHIPDGM;
|
|
|
|
#if 0
|
|
/*
|
|
* looks okey, but we need more sanity check.
|
|
* XXX should elaborate.
|
|
*/
|
|
if (ah->ah_nxt == IPPROTO_IPV6) {
|
|
struct ip6_hdr *nip6;
|
|
size_t sizoff;
|
|
|
|
sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
|
|
|
|
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1
|
|
+ sizeof(struct ip6_hdr), IPPROTO_DONE);
|
|
|
|
nip6 = (struct ip6_hdr *)((u_char *)(ah + 1) + sizoff + siz1);
|
|
if (!IN6_ARE_ADDR_EQUAL(&nip6->ip6_src, &ip6->ip6_src)
|
|
|| !IN6_ARE_ADDR_EQUAL(&nip6->ip6_dst, &ip6->ip6_dst)) {
|
|
m->m_flags &= ~M_AUTHIPHDR;
|
|
m->m_flags &= ~M_AUTHIPDGM;
|
|
}
|
|
} else if (ah->ah_nxt == IPPROTO_IPIP) {
|
|
m->m_flags &= ~M_AUTHIPHDR;
|
|
m->m_flags &= ~M_AUTHIPDGM;
|
|
} else if (ah->ah_nxt == IPPROTO_IP) {
|
|
m->m_flags &= ~M_AUTHIPHDR;
|
|
m->m_flags &= ~M_AUTHIPDGM;
|
|
}
|
|
#endif
|
|
|
|
if (m->m_flags & M_AUTHIPHDR
|
|
&& m->m_flags & M_AUTHIPDGM) {
|
|
#if 0
|
|
ipseclog((LOG_DEBUG,
|
|
"IPv6 AH input: authentication succeess\n"));
|
|
#endif
|
|
ipsec6stat.in_ahauthsucc++;
|
|
} else {
|
|
ipseclog((LOG_WARNING,
|
|
"authentication failed in IPv6 AH input: %s %s\n",
|
|
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
|
|
ipsec6stat.in_ahauthfail++;
|
|
goto fail;
|
|
}
|
|
|
|
/*
|
|
* update sequence number.
|
|
*/
|
|
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
|
|
if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) {
|
|
ipsec6stat.in_ahreplay++;
|
|
goto fail;
|
|
}
|
|
}
|
|
|
|
/* was it transmitted over the IPsec tunnel SA? */
|
|
if (ipsec6_tunnel_validate(ip6, nxt, sav) && nxt == IPPROTO_IPV6) {
|
|
/*
|
|
* strip off all the headers that precedes AH.
|
|
* IP6 xx AH IP6' payload -> IP6' payload
|
|
*
|
|
* XXX more sanity checks
|
|
* XXX relationship with gif?
|
|
*/
|
|
size_t stripsiz = 0;
|
|
u_int32_t flowinfo; /*net endian*/
|
|
|
|
flowinfo = ip6->ip6_flow;
|
|
if (sav->flags & SADB_X_EXT_OLD) {
|
|
/* RFC 1826 */
|
|
stripsiz = sizeof(struct ah) + siz1;
|
|
} else {
|
|
/* RFC 2402 */
|
|
stripsiz = sizeof(struct newah) + siz1;
|
|
}
|
|
m_adj(m, off + stripsiz);
|
|
if (m->m_len < sizeof(*ip6)) {
|
|
/*
|
|
* m_pullup is prohibited in KAME IPv6 input processing
|
|
* but there's no other way!
|
|
*/
|
|
m = m_pullup(m, sizeof(*ip6));
|
|
if (!m) {
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
}
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
/* ECN consideration. */
|
|
ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow);
|
|
if (!key_checktunnelsanity(sav, AF_INET6,
|
|
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
|
|
ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch "
|
|
"in IPv6 AH input: %s %s\n",
|
|
ipsec6_logpacketstr(ip6, spi),
|
|
ipsec_logsastr(sav)));
|
|
ipsec6stat.in_inval++;
|
|
goto fail;
|
|
}
|
|
|
|
#if 0 /* XXX should we call ipfw rather than ipsec_in_reject? */
|
|
/* drop it if it does not match the default policy */
|
|
if (ipsec6_in_reject(m, NULL)) {
|
|
ipsec6stat.in_polvio++;
|
|
goto fail;
|
|
}
|
|
#endif
|
|
|
|
#if 1
|
|
/*
|
|
* should the inner packet be considered authentic?
|
|
* see comment in ah4_input().
|
|
*/
|
|
m->m_flags &= ~M_AUTHIPHDR;
|
|
m->m_flags &= ~M_AUTHIPDGM;
|
|
#endif
|
|
|
|
key_sa_recordxfer(sav, m);
|
|
|
|
s = splimp();
|
|
if (IF_QFULL(&ip6intrq)) {
|
|
ipsec6stat.in_inval++;
|
|
splx(s);
|
|
goto fail;
|
|
}
|
|
IF_ENQUEUE(&ip6intrq, m);
|
|
m = NULL;
|
|
schednetisr(NETISR_IPV6); /*can be skipped but to make sure*/
|
|
splx(s);
|
|
nxt = IPPROTO_DONE;
|
|
} else {
|
|
/*
|
|
* strip off AH.
|
|
*/
|
|
size_t stripsiz = 0;
|
|
char *prvnxtp;
|
|
|
|
/*
|
|
* Copy the value of the next header field of AH to the
|
|
* next header field of the previous header.
|
|
* This is necessary because AH will be stripped off below.
|
|
*/
|
|
prvnxtp = ip6_get_prevhdr(m, off); /* XXX */
|
|
*prvnxtp = nxt;
|
|
|
|
if (sav->flags & SADB_X_EXT_OLD) {
|
|
/* RFC 1826 */
|
|
stripsiz = sizeof(struct ah) + siz1;
|
|
} else {
|
|
/* RFC 2402 */
|
|
stripsiz = sizeof(struct newah) + siz1;
|
|
}
|
|
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
#ifndef PULLDOWN_TEST
|
|
/*
|
|
* We do deep-copy since KAME requires that
|
|
* the packet is placed in a single mbuf.
|
|
*/
|
|
ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
|
|
m->m_data += stripsiz;
|
|
m->m_len -= stripsiz;
|
|
m->m_pkthdr.len -= stripsiz;
|
|
#else
|
|
/*
|
|
* even in m_pulldown case, we need to strip off AH so that
|
|
* we can compute checksum for multiple AH correctly.
|
|
*/
|
|
if (m->m_len >= stripsiz + off) {
|
|
ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
|
|
m->m_data += stripsiz;
|
|
m->m_len -= stripsiz;
|
|
m->m_pkthdr.len -= stripsiz;
|
|
} else {
|
|
/*
|
|
* this comes with no copy if the boundary is on
|
|
* cluster
|
|
*/
|
|
struct mbuf *n;
|
|
|
|
n = m_split(m, off, M_DONTWAIT);
|
|
if (n == NULL) {
|
|
/* m is retained by m_split */
|
|
goto fail;
|
|
}
|
|
m_adj(n, stripsiz);
|
|
m_cat(m, n);
|
|
/* m_cat does not update m_pkthdr.len */
|
|
m->m_pkthdr.len += n->m_pkthdr.len;
|
|
}
|
|
#endif
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
/* XXX jumbogram */
|
|
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
|
|
|
|
key_sa_recordxfer(sav, m);
|
|
}
|
|
|
|
*offp = off;
|
|
*mp = m;
|
|
|
|
if (sav) {
|
|
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
|
|
printf("DP ah6_input call free SA:%p\n", sav));
|
|
key_freesav(sav);
|
|
}
|
|
ipsec6stat.in_success++;
|
|
return nxt;
|
|
|
|
fail:
|
|
if (sav) {
|
|
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
|
|
printf("DP ah6_input call free SA:%p\n", sav));
|
|
key_freesav(sav);
|
|
}
|
|
if (m)
|
|
m_freem(m);
|
|
return IPPROTO_DONE;
|
|
}
|
|
#endif /* INET6 */
|