ah_input.c

eCos/RedBoot for勤研ARM AnywhereII(4510) 含全部源代码

		}

		if (nxt != IPPROTO_DONE) {
			if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
			    ipsec4_in_reject(m, NULL)) {
				ipsecstat.in_polvio++;
				goto fail;
			}
#if defined(__FreeBSD__) && __FreeBSD__ >= 4
			(*inetsw[ip_protox[nxt]].pr_input)(m, off);
#else
			(*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt);
#endif
		} 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;
}

#if defined(__NetBSD__) && __NetBSD_Version__ >= 105080000	/* 1.5H */
/* assumes that ip header and ah header are contiguous on mbuf */
void *
ah4_ctlinput(cmd, sa, v)
	int cmd;
	struct sockaddr *sa;
	void *v;
{
	struct ip *ip = v;
	struct ah *ah;
	struct icmp *icp;
	struct secasvar *sav;

	if (sa->sa_family != AF_INET ||
	    sa->sa_len != sizeof(struct sockaddr_in))
		return NULL;
	if ((unsigned)cmd >= PRC_NCMDS)
		return NULL;
	if (cmd == PRC_MSGSIZE && ip_mtudisc && ip && ip->ip_v == 4) {
		/*
		 * Check to see if we have a valid SA corresponding to
		 * the address in the ICMP message payload.
		 */
		ah = (struct ah *)((caddr_t)ip + (ip->ip_hl << 2));
		if ((sav = key_allocsa(AF_INET,
				       (caddr_t) &ip->ip_src,
				       (caddr_t) &ip->ip_dst,
				       IPPROTO_AH, ah->ah_spi)) == NULL)
			return NULL;
		if (sav->state != SADB_SASTATE_MATURE &&
		    sav->state != SADB_SASTATE_DYING) {
			key_freesav(sav);
			return NULL;
		}

		/* XXX Further validation? */

		key_freesav(sav);

		/*
		 * Now that we've validated that we are actually communicating
		 * with the host indicated in the ICMP message, locate the
		 * ICMP header, recalculate the new MTU, and create the
		 * corresponding routing entry.
		 */
		icp = (struct icmp *)((caddr_t)ip -
		    offsetof(struct icmp, icmp_ip));
		icmp_mtudisc(icp, ip->ip_dst);

		return NULL;
	}

	return NULL;
}
#endif /* NetBSD 1.5H or later */
#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;
	const struct ah_algorithm *algo;
	size_t siz;
	size_t siz1;
	u_char *cksum;
	struct secasvar *sav = NULL;
	u_int16_t nxt;
	int s;
	size_t stripsiz = 0;

#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"));
		ipsec6stat.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;
	}

	algo = ah_algorithm_lookup(sav->alg_auth);
	if (!algo) {
		ipseclog((LOG_DEBUG, "IPv6 AH input: "
		    "unsupported authentication algorithm for spi %u\n",
		    (u_int32_t)ntohl(spi)));
		ipsec6stat.in_badspi++;
		goto fail;
	}

	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"));
		ipsec6stat.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 (sav->flags & SADB_X_EXT_OLD) {
		/* RFC 1826 */
		stripsiz = sizeof(struct ah) + siz1;
	} else {
		/* RFC 2402 */
		stripsiz = sizeof(struct newah) + siz1;
	}
	if (!ipsec_tunnel_device &&
	    ipsec6_tunnel_validate(m, off + stripsiz, nxt, sav)) {
		/*
		 * strip off all the headers that precedes AH.
		 *	IP6 xx AH IP6' payload -> IP6' payload
		 *
		 * XXX more sanity checks
		 * XXX relationship with gif?
		 */
		u_int32_t flowinfo;	/* net endian */

		flowinfo = ip6->ip6_flow;
		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 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);
		if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 ||
		    ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) {
			ipsec6stat.in_nomem++;
			goto fail;
		}

		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.
		 */
		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;

		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);
		if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) {
			ipsec6stat.in_nomem++;
			goto fail;
		}
	}

	*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;
}

void
ah6_ctlinput(cmd, sa, d)
	int cmd;
	struct sockaddr *sa;
	void *d;
{
	const struct newah *ahp;
	struct newah ah;
	struct secasvar *sav;
	struct ip6_hdr *ip6;
	struct mbuf *m;
	struct ip6ctlparam *ip6cp = NULL;
	int off=0;
	struct sockaddr_in6 sa6_src, sa6_dst;

	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;
	}

	if (ip6) {
		/*
		 * XXX: We assume that when ip6 is non NULL,
		 * M and OFF are valid.
		 */

		/* check if we can safely examine src and dst ports */
		if (m->m_pkthdr.len < off + sizeof(ah))
			return;

		if (m->m_len < off + sizeof(ah)) {
			/*
			 * this should be rare case,
			 * so we compromise on this copy...
			 */
			m_copydata(m, off, sizeof(ah), (caddr_t)&ah);
			ahp = &ah;
		} else
			ahp = (struct newah *)(mtod(m, caddr_t) + off);

		if (cmd == PRC_MSGSIZE) {
			int valid = 0;

			/*
			 * Check to see if we have a valid SA corresponding to
			 * the address in the ICMP message payload.
			 */
			sav = key_allocsa(AF_INET6,
					  (caddr_t)&sa6_src.sin6_addr,
					  (caddr_t)&sa6_dst.sin6_addr,
					  IPPROTO_AH, ahp->ah_spi);
			if (sav) {
				if (sav->state == SADB_SASTATE_MATURE ||
				    sav->state == SADB_SASTATE_DYING)
					valid++;
				key_freesav(sav);
			}

			/* XXX Further validation? */

			/*
			 * Depending on the value of "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((struct ip6ctlparam *)d, valid);
		}

		/* we normally notify single pcb here */
	} else {
		/* we normally notify any pcb here */
	}
}
#endif /* INET6 */