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darling-xnu/bsd/netinet6/esp_input.c

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/*
* Copyright (c) 2008-2016 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* $FreeBSD: src/sys/netinet6/esp_input.c,v 1.1.2.3 2001/07/03 11:01:50 ume Exp $ */
/* $KAME: esp_input.c,v 1.55 2001/03/23 08:08:47 itojun Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#define _IP_VHL
/*
* RFC1827/2406 Encapsulated Security Payload.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mcache.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/if_ipsec.h>
#include <net/route.h>
#include <kern/cpu_number.h>
#include <kern/locks.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_var.h>
#include <netinet/ip_ecn.h>
#include <netinet/in_pcb.h>
#include <netinet/udp.h>
#include <netinet/tcp.h>
#include <netinet/in_tclass.h>
#include <netinet6/ip6_ecn.h>
#include <netinet/ip6.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/ipsec.h>
#include <netinet6/ipsec6.h>
#include <netinet6/ah.h>
#include <netinet6/ah6.h>
#include <netinet6/esp.h>
#include <netinet6/esp6.h>
#include <netkey/key.h>
#include <netkey/keydb.h>
#include <netkey/key_debug.h>
#include <net/kpi_protocol.h>
#include <netinet/kpi_ipfilter_var.h>
#include <net/net_osdep.h>
#include <mach/sdt.h>
#include <corecrypto/cc.h>
#include <sys/kdebug.h>
#define DBG_LAYER_BEG NETDBG_CODE(DBG_NETIPSEC, 1)
#define DBG_LAYER_END NETDBG_CODE(DBG_NETIPSEC, 3)
#define DBG_FNC_ESPIN NETDBG_CODE(DBG_NETIPSEC, (6 << 8))
#define DBG_FNC_DECRYPT NETDBG_CODE(DBG_NETIPSEC, (7 << 8))
#define IPLEN_FLIPPED
extern lck_mtx_t *sadb_mutex;
#define ESPMAXLEN \
(sizeof(struct esp) < sizeof(struct newesp) \
? sizeof(struct newesp) : sizeof(struct esp))
static struct ip *
esp4_input_strip_udp_encap(struct mbuf *m, int iphlen)
{
// strip the udp header that's encapsulating ESP
struct ip *ip;
u_int8_t stripsiz = (u_int8_t)sizeof(struct udphdr);
ip = mtod(m, __typeof__(ip));
ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), iphlen);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
ip = mtod(m, __typeof__(ip));
ip->ip_len = ip->ip_len - stripsiz;
ip->ip_p = IPPROTO_ESP;
return ip;
}
static struct ip6_hdr *
esp6_input_strip_udp_encap(struct mbuf *m, int ip6hlen)
{
// strip the udp header that's encapsulating ESP
struct ip6_hdr *ip6;
u_int8_t stripsiz = (u_int8_t)sizeof(struct udphdr);
ip6 = mtod(m, __typeof__(ip6));
ovbcopy((caddr_t)ip6, (caddr_t)(((u_char *)ip6) + stripsiz), ip6hlen);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
ip6 = mtod(m, __typeof__(ip6));
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
ip6->ip6_nxt = IPPROTO_ESP;
return ip6;
}
static void
esp_input_log(struct mbuf *m, struct secasvar *sav, u_int32_t spi, u_int32_t seq)
{
if (net_mpklog_enabled &&
(sav->sah->ipsec_if->if_xflags & IFXF_MPK_LOG) == IFXF_MPK_LOG) {
struct tcphdr th = {};
u_int32_t proto_len = 0;
u_int8_t iphlen = 0;
u_int8_t proto = 0;
struct ip *inner_ip = mtod(m, struct ip *);
if (IP_VHL_V(inner_ip->ip_vhl) == 4) {
iphlen = (u_int8_t)(IP_VHL_HL(inner_ip->ip_vhl) << 2);
proto = inner_ip->ip_p;
} else if (IP_VHL_V(inner_ip->ip_vhl) == 6) {
struct ip6_hdr *inner_ip6 = mtod(m, struct ip6_hdr *);
iphlen = sizeof(struct ip6_hdr);
proto = inner_ip6->ip6_nxt;
}
if (proto == IPPROTO_TCP) {
if ((int)(iphlen + sizeof(th)) <= m->m_pkthdr.len) {
m_copydata(m, iphlen, sizeof(th), (u_int8_t *)&th);
}
proto_len = m->m_pkthdr.len - iphlen - (th.th_off << 2);
MPKL_ESP_INPUT_TCP(esp_mpkl_log_object,
ntohl(spi), seq,
ntohs(th.th_sport), ntohs(th.th_dport),
ntohl(th.th_seq), proto_len);
}
}
}
void
esp4_input(struct mbuf *m, int off)
{
(void)esp4_input_extended(m, off, NULL);
}
struct mbuf *
esp4_input_extended(struct mbuf *m, int off, ifnet_t interface)
{
struct ip *ip;
struct ip6_hdr *ip6;
struct esp *esp;
struct esptail esptail;
u_int32_t spi;
u_int32_t seq;
struct secasvar *sav = NULL;
size_t taillen;
u_int16_t nxt;
const struct esp_algorithm *algo;
int ivlen;
size_t esplen;
u_int8_t hlen;
sa_family_t ifamily;
struct mbuf *out_m = NULL;
mbuf_traffic_class_t traffic_class = 0;
KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_START, 0, 0, 0, 0, 0);
/* sanity check for alignment. */
if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
ipseclog((LOG_ERR, "IPv4 ESP input: packet alignment problem "
"(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (m->m_len < off + ESPMAXLEN) {
m = m_pullup(m, off + ESPMAXLEN);
if (!m) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: can't pullup in esp4_input\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
}
m->m_pkthdr.csum_flags &= ~CSUM_RX_FLAGS;
/* Expect 32-bit aligned data pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip = mtod(m, struct ip *);
// expect udp-encap and esp packets only
if (ip->ip_p != IPPROTO_ESP &&
!(ip->ip_p == IPPROTO_UDP && off >= sizeof(struct udphdr))) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: invalid protocol type\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
esp = (struct esp *)(void *)(((u_int8_t *)ip) + off);
#ifdef _IP_VHL
hlen = (u_int8_t)(IP_VHL_HL(ip->ip_vhl) << 2);
#else
hlen = ip->ip_hl << 2;
#endif
/* find the sassoc. */
spi = esp->esp_spi;
if ((sav = key_allocsa_extended(AF_INET,
(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
IPPROTO_ESP, spi, interface)) == 0) {
ipseclog((LOG_WARNING,
"IPv4 ESP input: no key association found for spi %u (0x%08x)\n",
(u_int32_t)ntohl(spi), (u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsecstat.in_nosa);
goto bad;
}
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP esp4_input called to allocate SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
if (sav->state != SADB_SASTATE_MATURE
&& sav->state != SADB_SASTATE_DYING) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: non-mature/dying SA found for spi %u (0x%08x)\n",
(u_int32_t)ntohl(spi), (u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsecstat.in_badspi);
goto bad;
}
algo = esp_algorithm_lookup(sav->alg_enc);
if (!algo) {
ipseclog((LOG_DEBUG, "IPv4 ESP input: "
"unsupported encryption algorithm for spi %u (0x%08x)\n",
(u_int32_t)ntohl(spi), (u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsecstat.in_badspi);
goto bad;
}
/* check if we have proper ivlen information */
ivlen = sav->ivlen;
if (ivlen < 0) {
ipseclog((LOG_ERR, "inproper ivlen in IPv4 ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
seq = ntohl(((struct newesp *)esp)->esp_seq);
if ((sav->flags2 & SADB_X_EXT_SA2_SEQ_PER_TRAFFIC_CLASS) ==
SADB_X_EXT_SA2_SEQ_PER_TRAFFIC_CLASS) {
u_int8_t dscp = ip->ip_tos >> IPTOS_DSCP_SHIFT;
traffic_class = rfc4594_dscp_to_tc(dscp);
}
/* Save ICV from packet for verification later */
size_t siz = 0;
unsigned char saved_icv[AH_MAXSUMSIZE];
if (algo->finalizedecrypt) {
siz = algo->icvlen;
VERIFY(siz <= USHRT_MAX);
m_copydata(m, m->m_pkthdr.len - (u_short)siz, (u_short)siz, (caddr_t) saved_icv);
goto delay_icv;
}
if (!((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[traffic_class] != NULL &&
(sav->alg_auth && sav->key_auth))) {
goto noreplaycheck;
}
if (sav->alg_auth == SADB_X_AALG_NULL ||
sav->alg_auth == SADB_AALG_NONE) {
goto noreplaycheck;
}
/*
* check for sequence number.
*/
_CASSERT(MBUF_TC_MAX <= UINT8_MAX);
if (ipsec_chkreplay(seq, sav, (u_int8_t)traffic_class)) {
; /*okey*/
} else {
IPSEC_STAT_INCREMENT(ipsecstat.in_espreplay);
ipseclog((LOG_WARNING,
"replay packet in IPv4 ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
goto bad;
}
/* check ICV */
{
u_char sum0[AH_MAXSUMSIZE] __attribute__((aligned(4)));
u_char sum[AH_MAXSUMSIZE] __attribute__((aligned(4)));
const struct ah_algorithm *sumalgo;
sumalgo = ah_algorithm_lookup(sav->alg_auth);
if (!sumalgo) {
goto noreplaycheck;
}
siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (AH_MAXSUMSIZE < siz) {
ipseclog((LOG_DEBUG,
"internal error: AH_MAXSUMSIZE must be larger than %u\n",
(u_int32_t)siz));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
m_copydata(m, m->m_pkthdr.len - (int)siz, (int)siz, (caddr_t) &sum0[0]);
if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
ipseclog((LOG_WARNING, "auth fail in IPv4 ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_espauthfail);
goto bad;
}
if (cc_cmp_safe(siz, sum0, sum)) {
ipseclog((LOG_WARNING, "cc_cmp fail in IPv4 ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_espauthfail);
goto bad;
}
delay_icv:
/* strip off the authentication data */
m_adj(m, (int)-siz);
ip = mtod(m, struct ip *);
#ifdef IPLEN_FLIPPED
ip->ip_len = ip->ip_len - (u_short)siz;
#else
ip->ip_len = htons(ntohs(ip->ip_len) - siz);
#endif
m->m_flags |= M_AUTHIPDGM;
IPSEC_STAT_INCREMENT(ipsecstat.in_espauthsucc);
}
/*
* update sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[traffic_class] != NULL) {
if (ipsec_updatereplay(seq, sav, (u_int8_t)traffic_class)) {
IPSEC_STAT_INCREMENT(ipsecstat.in_espreplay);
goto bad;
}
}
noreplaycheck:
/* process main esp header. */
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1827 */
esplen = sizeof(struct esp);
} else {
/* RFC 2406 */
if (sav->flags & SADB_X_EXT_DERIV) {
esplen = sizeof(struct esp);
} else {
esplen = sizeof(struct newesp);
}
}
if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
ipseclog((LOG_WARNING,
"IPv4 ESP input: packet too short\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (m->m_len < off + esplen + ivlen) {
m = m_pullup(m, (int)(off + esplen + ivlen));
if (!m) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: can't pullup in esp4_input\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
}
/*
* pre-compute and cache intermediate key
*/
if (esp_schedule(algo, sav) != 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
/*
* decrypt the packet.
*/
if (!algo->decrypt) {
panic("internal error: no decrypt function");
}
KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_START, 0, 0, 0, 0, 0);
if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
/* m is already freed */
m = NULL;
ipseclog((LOG_ERR, "decrypt fail in IPv4 ESP input: %s\n",
ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1, 0, 0, 0, 0);
goto bad;
}
KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 2, 0, 0, 0, 0);
IPSEC_STAT_INCREMENT(ipsecstat.in_esphist[sav->alg_enc]);
m->m_flags |= M_DECRYPTED;
if (algo->finalizedecrypt) {
if ((*algo->finalizedecrypt)(sav, saved_icv, algo->icvlen)) {
ipseclog((LOG_ERR, "esp4 packet decryption ICV failure\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1, 0, 0, 0, 0);
goto bad;
}
}
/*
* find the trailer of the ESP.
*/
m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
(caddr_t)&esptail);
nxt = esptail.esp_nxt;
taillen = esptail.esp_padlen + sizeof(esptail);
if (m->m_pkthdr.len < taillen
|| m->m_pkthdr.len - taillen < hlen) { /*?*/
ipseclog((LOG_WARNING,
"bad pad length in IPv4 ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
/* strip off the trailing pad area. */
m_adj(m, (int)-taillen);
ip = mtod(m, struct ip *);
#ifdef IPLEN_FLIPPED
ip->ip_len = ip->ip_len - (u_short)taillen;
#else
ip->ip_len = htons(ntohs(ip->ip_len) - taillen);
#endif
if (ip->ip_p == IPPROTO_UDP) {
// offset includes the outer ip and udp header lengths.
if (m->m_len < off) {
m = m_pullup(m, off);
if (!m) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: invalid udp encapsulated ESP packet length \n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
ip = mtod(m, struct ip *);
}
// check the UDP encap header to detect changes in the source port, and then strip the header
off -= sizeof(struct udphdr); // off no longer includes the udphdr's size
// if peer is behind nat and this is the latest esp packet
if ((sav->flags & SADB_X_EXT_NATT_DETECTED_PEER) != 0 &&
(sav->flags & SADB_X_EXT_OLD) == 0 &&
seq && sav->replay[traffic_class] &&
seq >= sav->replay[traffic_class]->lastseq) {
struct udphdr *encap_uh = (__typeof__(encap_uh))(void *)((caddr_t)ip + off);
if (encap_uh->uh_sport &&
ntohs(encap_uh->uh_sport) != sav->remote_ike_port) {
sav->remote_ike_port = ntohs(encap_uh->uh_sport);
}
}
ip = esp4_input_strip_udp_encap(m, off);
esp = (struct esp *)(void *)(((u_int8_t *)ip) + off);
}
/* was it transmitted over the IPsec tunnel SA? */
if (ipsec4_tunnel_validate(m, (int)(off + esplen + ivlen), nxt, sav, &ifamily)) {
ifaddr_t ifa;
struct sockaddr_storage addr;
/*
* strip off all the headers that precedes ESP header.
* IP4 xx ESP IP4' payload -> IP4' payload
*
* XXX more sanity checks
* XXX relationship with gif?
*/
u_int8_t tos, otos;
int sum;
tos = ip->ip_tos;
m_adj(m, (int)(off + esplen + ivlen));
if (ifamily == AF_INET) {
struct sockaddr_in *ipaddr;
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (!m) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
}
ip = mtod(m, struct ip *);
/* ECN consideration. */
otos = ip->ip_tos;
if (ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos) == 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (otos != ip->ip_tos) {
sum = ~ntohs(ip->ip_sum) & 0xffff;
sum += (~otos & 0xffff) + ip->ip_tos;
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16); /* add carry */
ip->ip_sum = htons(~sum & 0xffff);
}
if (!key_checktunnelsanity(sav, AF_INET,
(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
"in ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
bzero(&addr, sizeof(addr));
ipaddr = (__typeof__(ipaddr)) & addr;
ipaddr->sin_family = AF_INET;
ipaddr->sin_len = sizeof(*ipaddr);
ipaddr->sin_addr = ip->ip_dst;
} else if (ifamily == AF_INET6) {
struct sockaddr_in6 *ip6addr;
/*
* m_pullup is prohibited in KAME IPv6 input processing
* but there's no other way!
*/
if (m->m_len < sizeof(*ip6)) {
m = m_pullup(m, sizeof(*ip6));
if (!m) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
}
/*
* Expect 32-bit aligned data pointer on strict-align
* platforms.
*/
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip6 = mtod(m, struct ip6_hdr *);
/* ECN consideration. */
if (ip64_ecn_egress(ip4_ipsec_ecn, &tos, &ip6->ip6_flow) == 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (!key_checktunnelsanity(sav, AF_INET6,
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
"in ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
bzero(&addr, sizeof(addr));
ip6addr = (__typeof__(ip6addr)) & addr;
ip6addr->sin6_family = AF_INET6;
ip6addr->sin6_len = sizeof(*ip6addr);
ip6addr->sin6_addr = ip6->ip6_dst;
} else {
ipseclog((LOG_ERR, "ipsec tunnel unsupported address family "
"in ESP input\n"));
goto bad;
}
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_nomem);
goto bad;
}
// update the receiving interface address based on the inner address
ifa = ifa_ifwithaddr((struct sockaddr *)&addr);
if (ifa) {
m->m_pkthdr.rcvif = ifa->ifa_ifp;
IFA_REMREF(ifa);
}
/* Clear the csum flags, they can't be valid for the inner headers */
m->m_pkthdr.csum_flags = 0;
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
esp_input_log(m, sav, spi, seq);
ipsec_save_wake_packet(m, ntohl(spi), seq);
// Return mbuf
if (interface != NULL &&
interface == ipsec_if) {
out_m = m;
ifnet_release(ipsec_if);
goto done;
}
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
goto done;
} else {
goto bad;
}
}
if (proto_input(ifamily == AF_INET ? PF_INET : PF_INET6, m) != 0) {
goto bad;
}
nxt = IPPROTO_DONE;
KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 2, 0, 0, 0, 0);
} else {
/*
* strip off ESP header and IV.
* even in m_pulldown case, we need to strip off ESP so that
* we can always compute checksum for AH correctly.
*/
size_t stripsiz;
stripsiz = esplen + ivlen;
ip = mtod(m, struct ip *);
ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
ip = mtod(m, struct ip *);
#ifdef IPLEN_FLIPPED
ip->ip_len = ip->ip_len - (u_short)stripsiz;
#else
ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
#endif
ip->ip_p = (u_int8_t)nxt;
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_nomem);
goto bad;
}
/*
* Set the csum valid flag, if we authenticated the
* packet, the payload shouldn't be corrupt unless
* it was corrupted before being signed on the other
* side.
*/
if (nxt == IPPROTO_TCP || nxt == IPPROTO_UDP) {
m->m_pkthdr.csum_flags = CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xFFFF;
_CASSERT(offsetof(struct pkthdr, csum_data) == offsetof(struct pkthdr, csum_rx_val));
}
if (nxt != IPPROTO_DONE) {
if ((ip_protox[nxt]->pr_flags & PR_LASTHDR) != 0 &&
ipsec4_in_reject(m, NULL)) {
IPSEC_STAT_INCREMENT(ipsecstat.in_polvio);
goto bad;
}
KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 3, 0, 0, 0, 0);
/* translate encapsulated UDP port ? */
if ((sav->flags & SADB_X_EXT_NATT_MULTIPLEUSERS) != 0) {
struct udphdr *udp;
if (nxt != IPPROTO_UDP) { /* not UPD packet - drop it */
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (m->m_len < off + sizeof(struct udphdr)) {
m = m_pullup(m, off + sizeof(struct udphdr));
if (!m) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: can't pullup UDP header in esp4_input\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
ip = mtod(m, struct ip *);
}
udp = (struct udphdr *)(void *)(((u_int8_t *)ip) + off);
lck_mtx_lock(sadb_mutex);
if (sav->natt_encapsulated_src_port == 0) {
sav->natt_encapsulated_src_port = udp->uh_sport;
} else if (sav->natt_encapsulated_src_port != udp->uh_sport) { /* something wrong */
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
lck_mtx_unlock(sadb_mutex);
goto bad;
}
lck_mtx_unlock(sadb_mutex);
udp->uh_sport = htons(sav->remote_ike_port);
udp->uh_sum = 0;
}
DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif,
struct ip *, ip, struct ip6_hdr *, NULL);
// Input via IPsec interface legacy path
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
int mlen;
if ((mlen = m_length2(m, NULL)) < hlen) {
ipseclog((LOG_DEBUG,
"IPv4 ESP input: decrypted packet too short %d < %u\n",
mlen, hlen));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
ifnet_release(ipsec_if);
goto bad;
}
ip->ip_len = htons(ip->ip_len + hlen);
ip->ip_off = htons(ip->ip_off);
ip->ip_sum = 0;
ip->ip_sum = ip_cksum_hdr_in(m, hlen);
esp_input_log(m, sav, spi, seq);
ipsec_save_wake_packet(m, ntohl(spi), seq);
// Return mbuf
if (interface != NULL &&
interface == ipsec_if) {
out_m = m;
ifnet_release(ipsec_if);
goto done;
}
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
goto done;
} else {
goto bad;
}
}
ip_proto_dispatch_in(m, off, (u_int8_t)nxt, 0);
} else {
m_freem(m);
}
m = NULL;
}
done:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP esp4_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
IPSEC_STAT_INCREMENT(ipsecstat.in_success);
return out_m;
bad:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP esp4_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
if (m) {
m_freem(m);
}
KERNEL_DEBUG(DBG_FNC_ESPIN | DBG_FUNC_END, 4, 0, 0, 0, 0);
return out_m;
}
int
esp6_input(struct mbuf **mp, int *offp, int proto)
{
return esp6_input_extended(mp, offp, proto, NULL);
}
int
esp6_input_extended(struct mbuf **mp, int *offp, int proto, ifnet_t interface)
{
#pragma unused(proto)
struct mbuf *m = *mp;
int off = *offp;
struct ip *ip;
struct ip6_hdr *ip6;
struct esp *esp;
struct esptail esptail;
u_int32_t spi;
u_int32_t seq;
struct secasvar *sav = NULL;
u_int16_t nxt;
char *nproto;
const struct esp_algorithm *algo;
int ivlen;
size_t esplen;
u_int16_t taillen;
sa_family_t ifamily;
mbuf_traffic_class_t traffic_class = 0;
/* sanity check for alignment. */
if (off % 4 != 0 || m->m_pkthdr.len % 4 != 0) {
ipseclog((LOG_ERR, "IPv6 ESP input: packet alignment problem "
"(off=%d, pktlen=%d)\n", off, m->m_pkthdr.len));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, ESPMAXLEN, {return IPPROTO_DONE;});
esp = (struct esp *)(void *)(mtod(m, caddr_t) + off);
#else
IP6_EXTHDR_GET(esp, struct esp *, m, off, ESPMAXLEN);
if (esp == NULL) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
return IPPROTO_DONE;
}
#endif
m->m_pkthdr.csum_flags &= ~CSUM_RX_FLAGS;
/* Expect 32-bit data aligned pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip6 = mtod(m, struct ip6_hdr *);
if (ntohs(ip6->ip6_plen) == 0) {
ipseclog((LOG_ERR, "IPv6 ESP input: "
"ESP with IPv6 jumbogram is not supported.\n"));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
nproto = ip6_get_prevhdr(m, off);
if (nproto == NULL || (*nproto != IPPROTO_ESP &&
!(*nproto == IPPROTO_UDP && off >= sizeof(struct udphdr)))) {
ipseclog((LOG_DEBUG, "IPv6 ESP input: invalid protocol type\n"));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
/* find the sassoc. */
spi = esp->esp_spi;
if ((sav = key_allocsa_extended(AF_INET6,
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
IPPROTO_ESP, spi, interface)) == 0) {
ipseclog((LOG_WARNING,
"IPv6 ESP input: no key association found for spi %u (0x%08x) seq %u"
" src %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
" dst %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x if %s\n",
(u_int32_t)ntohl(spi), (u_int32_t)ntohl(spi), ntohl(((struct newesp *)esp)->esp_seq),
ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[0]), ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[1]),
ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[2]), ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[3]),
ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[4]), ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[5]),
ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[6]), ntohs(ip6->ip6_src.__u6_addr.__u6_addr16[7]),
ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[0]), ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[1]),
ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[2]), ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[3]),
ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[4]), ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[5]),
ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[6]), ntohs(ip6->ip6_dst.__u6_addr.__u6_addr16[7]),
((interface != NULL) ? if_name(interface) : "NONE")));
IPSEC_STAT_INCREMENT(ipsec6stat.in_nosa);
goto bad;
}
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP esp6_input called to allocate SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
if (sav->state != SADB_SASTATE_MATURE
&& sav->state != SADB_SASTATE_DYING) {
ipseclog((LOG_DEBUG,
"IPv6 ESP input: non-mature/dying SA found for spi %u (0x%08x)\n",
(u_int32_t)ntohl(spi), (u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi);
goto bad;
}
algo = esp_algorithm_lookup(sav->alg_enc);
if (!algo) {
ipseclog((LOG_DEBUG, "IPv6 ESP input: "
"unsupported encryption algorithm for spi %u (0x%08x)\n",
(u_int32_t)ntohl(spi), (u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi);
goto bad;
}
/* check if we have proper ivlen information */
ivlen = sav->ivlen;
if (ivlen < 0) {
ipseclog((LOG_ERR, "inproper ivlen in IPv6 ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_badspi);
goto bad;
}
seq = ntohl(((struct newesp *)esp)->esp_seq);
if ((sav->flags2 & SADB_X_EXT_SA2_SEQ_PER_TRAFFIC_CLASS) ==
SADB_X_EXT_SA2_SEQ_PER_TRAFFIC_CLASS) {
u_int8_t dscp = (ntohl(ip6->ip6_flow) & IP6FLOW_DSCP_MASK) >> IP6FLOW_DSCP_SHIFT;
traffic_class = rfc4594_dscp_to_tc(dscp);
}
/* Save ICV from packet for verification later */
size_t siz = 0;
unsigned char saved_icv[AH_MAXSUMSIZE];
if (algo->finalizedecrypt) {
siz = algo->icvlen;
VERIFY(siz <= UINT16_MAX);
m_copydata(m, m->m_pkthdr.len - (int)siz, (int)siz, (caddr_t) saved_icv);
goto delay_icv;
}
if (!((sav->flags & SADB_X_EXT_OLD) == 0 &&
sav->replay[traffic_class] != NULL &&
(sav->alg_auth && sav->key_auth))) {
goto noreplaycheck;
}
if (sav->alg_auth == SADB_X_AALG_NULL ||
sav->alg_auth == SADB_AALG_NONE) {
goto noreplaycheck;
}
/*
* check for sequence number.
*/
if (ipsec_chkreplay(seq, sav, (u_int8_t)traffic_class)) {
; /*okey*/
} else {
IPSEC_STAT_INCREMENT(ipsec6stat.in_espreplay);
ipseclog((LOG_WARNING,
"replay packet in IPv6 ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
goto bad;
}
/* check ICV */
{
u_char sum0[AH_MAXSUMSIZE] __attribute__((aligned(4)));
u_char sum[AH_MAXSUMSIZE] __attribute__((aligned(4)));
const struct ah_algorithm *sumalgo;
sumalgo = ah_algorithm_lookup(sav->alg_auth);
if (!sumalgo) {
goto noreplaycheck;
}
siz = (((*sumalgo->sumsiz)(sav) + 3) & ~(4 - 1));
if (m->m_pkthdr.len < off + ESPMAXLEN + siz) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (AH_MAXSUMSIZE < siz) {
ipseclog((LOG_DEBUG,
"internal error: AH_MAXSUMSIZE must be larger than %u\n",
(u_int32_t)siz));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
m_copydata(m, m->m_pkthdr.len - (int)siz, (int)siz, (caddr_t) &sum0[0]);
if (esp_auth(m, off, m->m_pkthdr.len - off - siz, sav, sum)) {
ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthfail);
goto bad;
}
if (cc_cmp_safe(siz, sum0, sum)) {
ipseclog((LOG_WARNING, "auth fail in IPv6 ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthfail);
goto bad;
}
delay_icv:
/* strip off the authentication data */
m_adj(m, (int)-siz);
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - (u_int16_t)siz);
m->m_flags |= M_AUTHIPDGM;
IPSEC_STAT_INCREMENT(ipsec6stat.in_espauthsucc);
}
/*
* update sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[traffic_class] != NULL) {
if (ipsec_updatereplay(seq, sav, (u_int8_t)traffic_class)) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_espreplay);
goto bad;
}
}
noreplaycheck:
/* process main esp header. */
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1827 */
esplen = sizeof(struct esp);
} else {
/* RFC 2406 */
if (sav->flags & SADB_X_EXT_DERIV) {
esplen = sizeof(struct esp);
} else {
esplen = sizeof(struct newesp);
}
}
if (m->m_pkthdr.len < off + esplen + ivlen + sizeof(esptail)) {
ipseclog((LOG_WARNING,
"IPv6 ESP input: packet too short\n"));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, (int)(esplen + ivlen), return IPPROTO_DONE); /*XXX*/
#else
IP6_EXTHDR_GET(esp, struct esp *, m, off, esplen + ivlen);
if (esp == NULL) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
m = NULL;
goto bad;
}
#endif
ip6 = mtod(m, struct ip6_hdr *); /*set it again just in case*/
/*
* pre-compute and cache intermediate key
*/
if (esp_schedule(algo, sav) != 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
/*
* decrypt the packet.
*/
if (!algo->decrypt) {
panic("internal error: no decrypt function");
}
if ((*algo->decrypt)(m, off, sav, algo, ivlen)) {
/* m is already freed */
m = NULL;
ipseclog((LOG_ERR, "decrypt fail in IPv6 ESP input: %s\n",
ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
IPSEC_STAT_INCREMENT(ipsec6stat.in_esphist[sav->alg_enc]);
m->m_flags |= M_DECRYPTED;
if (algo->finalizedecrypt) {
if ((*algo->finalizedecrypt)(sav, saved_icv, algo->icvlen)) {
ipseclog((LOG_ERR, "esp6 packet decryption ICV failure\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
KERNEL_DEBUG(DBG_FNC_DECRYPT | DBG_FUNC_END, 1, 0, 0, 0, 0);
goto bad;
}
}
/*
* find the trailer of the ESP.
*/
m_copydata(m, m->m_pkthdr.len - sizeof(esptail), sizeof(esptail),
(caddr_t)&esptail);
nxt = esptail.esp_nxt;
taillen = esptail.esp_padlen + sizeof(esptail);
if (m->m_pkthdr.len < taillen
|| m->m_pkthdr.len - taillen < sizeof(struct ip6_hdr)) { /*?*/
ipseclog((LOG_WARNING,
"bad pad length in IPv6 ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
/* strip off the trailing pad area. */
m_adj(m, -taillen);
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - taillen);
if (*nproto == IPPROTO_UDP) {
// offset includes the outer ip and udp header lengths.
if (m->m_len < off) {
m = m_pullup(m, off);
if (!m) {
ipseclog((LOG_DEBUG,
"IPv6 ESP input: invalid udp encapsulated ESP packet length\n"));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
ip6 = mtod(m, struct ip6_hdr *);
}
// check the UDP encap header to detect changes in the source port, and then strip the header
off -= sizeof(struct udphdr); // off no longer includes the udphdr's size
// if peer is behind nat and this is the latest esp packet
if ((sav->flags & SADB_X_EXT_NATT_DETECTED_PEER) != 0 &&
(sav->flags & SADB_X_EXT_OLD) == 0 &&
seq && sav->replay[traffic_class] &&
seq >= sav->replay[traffic_class]->lastseq) {
struct udphdr *encap_uh = (__typeof__(encap_uh))(void *)((caddr_t)ip6 + off);
if (encap_uh->uh_sport &&
ntohs(encap_uh->uh_sport) != sav->remote_ike_port) {
sav->remote_ike_port = ntohs(encap_uh->uh_sport);
}
}
ip6 = esp6_input_strip_udp_encap(m, off);
esp = (struct esp *)(void *)(((u_int8_t *)ip6) + off);
}
/* was it transmitted over the IPsec tunnel SA? */
if (ipsec6_tunnel_validate(m, (int)(off + esplen + ivlen), nxt, sav, &ifamily)) {
ifaddr_t ifa;
struct sockaddr_storage addr;
/*
* strip off all the headers that precedes ESP header.
* IP6 xx ESP 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, (int)(off + esplen + ivlen));
if (ifamily == AF_INET6) {
struct sockaddr_in6 *ip6addr;
if (m->m_len < sizeof(*ip6)) {
#ifndef PULLDOWN_TEST
/*
* m_pullup is prohibited in KAME IPv6 input processing
* but there's no other way!
*/
#else
/* okay to pullup in m_pulldown style */
#endif
m = m_pullup(m, sizeof(*ip6));
if (!m) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
}
ip6 = mtod(m, struct ip6_hdr *);
/* ECN consideration. */
if (ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow) == 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
if (!key_checktunnelsanity(sav, AF_INET6,
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
"in IPv6 ESP input: %s %s\n",
ipsec6_logpacketstr(ip6, spi),
ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto bad;
}
bzero(&addr, sizeof(addr));
ip6addr = (__typeof__(ip6addr)) & addr;
ip6addr->sin6_family = AF_INET6;
ip6addr->sin6_len = sizeof(*ip6addr);
ip6addr->sin6_addr = ip6->ip6_dst;
} else if (ifamily == AF_INET) {
struct sockaddr_in *ipaddr;
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (!m) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
}
u_int8_t otos;
int sum;
ip = mtod(m, struct ip *);
otos = ip->ip_tos;
/* ECN consideration. */
if (ip46_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip->ip_tos) == 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
if (otos != ip->ip_tos) {
sum = ~ntohs(ip->ip_sum) & 0xffff;
sum += (~otos & 0xffff) + ip->ip_tos;
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16); /* add carry */
ip->ip_sum = htons(~sum & 0xffff);
}
if (!key_checktunnelsanity(sav, AF_INET,
(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
ipseclog((LOG_ERR, "ipsec tunnel address mismatch "
"in ESP input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto bad;
}
bzero(&addr, sizeof(addr));
ipaddr = (__typeof__(ipaddr)) & addr;
ipaddr->sin_family = AF_INET;
ipaddr->sin_len = sizeof(*ipaddr);
ipaddr->sin_addr = ip->ip_dst;
}
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0 ||
ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem);
goto bad;
}
// update the receiving interface address based on the inner address
ifa = ifa_ifwithaddr((struct sockaddr *)&addr);
if (ifa) {
m->m_pkthdr.rcvif = ifa->ifa_ifp;
IFA_REMREF(ifa);
}
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
esp_input_log(m, sav, spi, seq);
ipsec_save_wake_packet(m, ntohl(spi), seq);
// Return mbuf
if (interface != NULL &&
interface == ipsec_if) {
ifnet_release(ipsec_if);
goto done;
}
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
nxt = IPPROTO_DONE;
goto done;
} else {
goto bad;
}
}
if (proto_input(ifamily == AF_INET ? PF_INET : PF_INET6, m) != 0) {
goto bad;
}
nxt = IPPROTO_DONE;
} else {
/*
* strip off ESP header and IV.
* even in m_pulldown case, we need to strip off ESP so that
* we can always compute checksum for AH correctly.
*/
u_int16_t stripsiz;
char *prvnxtp;
/*
* Set the next header field of the previous header correctly.
*/
prvnxtp = ip6_get_prevhdr(m, off); /* XXX */
*prvnxtp = (u_int8_t)nxt;
VERIFY(esplen + ivlen <= UINT16_MAX);
stripsiz = (u_int16_t)(esplen + ivlen);
ip6 = mtod(m, struct ip6_hdr *);
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 bad;
}
m_adj(n, stripsiz);
/* m_cat does not update m_pkthdr.len */
m->m_pkthdr.len += n->m_pkthdr.len;
m_cat(m, n);
}
#ifndef PULLDOWN_TEST
/*
* KAME requires that the packet to be contiguous on the
* mbuf. We need to make that sure.
* this kind of code should be avoided.
* XXX other conditions to avoid running this part?
*/
if (m->m_len != m->m_pkthdr.len) {
struct mbuf *n = NULL;
int maxlen;
MGETHDR(n, M_DONTWAIT, MT_HEADER); /* MAC-OK */
maxlen = MHLEN;
if (n) {
M_COPY_PKTHDR(n, m);
}
if (n && m->m_pkthdr.len > maxlen) {
MCLGET(n, M_DONTWAIT);
maxlen = MCLBYTES;
if ((n->m_flags & M_EXT) == 0) {
m_free(n);
n = NULL;
}
}
if (!n) {
printf("esp6_input: mbuf allocation failed\n");
goto bad;
}
if (m->m_pkthdr.len <= maxlen) {
m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t));
n->m_len = m->m_pkthdr.len;
n->m_pkthdr.len = m->m_pkthdr.len;
n->m_next = NULL;
m_freem(m);
} else {
m_copydata(m, 0, maxlen, mtod(n, caddr_t));
n->m_len = maxlen;
n->m_pkthdr.len = m->m_pkthdr.len;
n->m_next = m;
m_adj(m, maxlen);
m->m_flags &= ~M_PKTHDR;
}
m = n;
}
#endif
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_ESP, spi) != 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem);
goto bad;
}
/*
* Set the csum valid flag, if we authenticated the
* packet, the payload shouldn't be corrupt unless
* it was corrupted before being signed on the other
* side.
*/
if (nxt == IPPROTO_TCP || nxt == IPPROTO_UDP) {
m->m_pkthdr.csum_flags = CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
m->m_pkthdr.csum_data = 0xFFFF;
_CASSERT(offsetof(struct pkthdr, csum_data) == offsetof(struct pkthdr, csum_rx_val));
}
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
esp_input_log(m, sav, spi, seq);
ipsec_save_wake_packet(m, ntohl(spi), seq);
// Return mbuf
if (interface != NULL &&
interface == ipsec_if) {
ifnet_release(ipsec_if);
goto done;
}
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
nxt = IPPROTO_DONE;
goto done;
} else {
goto bad;
}
}
}
done:
*offp = off;
*mp = m;
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP esp6_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
IPSEC_STAT_INCREMENT(ipsec6stat.in_success);
return nxt;
bad:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP esp6_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
if (m) {
m_freem(m);
}
if (interface != NULL) {
*mp = NULL;
}
return IPPROTO_DONE;
}
void
esp6_ctlinput(int cmd, struct sockaddr *sa, void *d, __unused struct ifnet *ifp)
{
const struct newesp *espp;
struct newesp esp;
struct ip6ctlparam *ip6cp = NULL, ip6cp1;
struct secasvar *sav;
struct ip6_hdr *ip6;
struct mbuf *m;
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) {
/*
* 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.
*/
/* check if we can safely examine src and dst ports */
if (m->m_pkthdr.len < off + sizeof(esp)) {
return;
}
if (m->m_len < off + sizeof(esp)) {
/*
* this should be rare case,
* so we compromise on this copy...
*/
m_copydata(m, off, sizeof(esp), (caddr_t)&esp);
espp = &esp;
} else {
espp = (struct newesp*)(void *)(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.
*/
sa6_src = ip6cp->ip6c_src;
sa6_dst = (struct sockaddr_in6 *)(void *)sa;
sav = key_allocsa(AF_INET6,
(caddr_t)&sa6_src->sin6_addr,
(caddr_t)&sa6_dst->sin6_addr,
IPPROTO_ESP, espp->esp_spi);
if (sav) {
if (sav->state == SADB_SASTATE_MATURE ||
sav->state == SADB_SASTATE_DYING) {
valid++;
}
key_freesav(sav, KEY_SADB_UNLOCKED);
}
/* 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);
}
} else {
/* we normally notify any pcb here */
}
}
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