gems-kernel/source/THIRDPARTY/xnu/bsd/netinet6/ip6_input.c
2024-06-03 11:29:39 -05:00

2568 lines
70 KiB
C

/*
* Copyright (c) 2003-2021 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@
*/
/*
* 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.
*/
/*
* Copyright (c) 1982, 1986, 1988, 1993
* The Regents of the University of California. 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)ip_input.c 8.2 (Berkeley) 1/4/94
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/kauth.h>
#include <sys/mcache.h>
#include <mach/mach_time.h>
#include <mach/sdt.h>
#include <pexpert/pexpert.h>
#include <dev/random/randomdev.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/kpi_protocol.h>
#include <net/ntstat.h>
#include <net/init.h>
#include <net/net_osdep.h>
#include <net/net_perf.h>
#include <net/if_ports_used.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#if INET
#include <netinet/ip.h>
#include <netinet/ip_icmp.h>
#endif /* INET */
#include <netinet/kpi_ipfilter_var.h>
#include <netinet/ip6.h>
#include <netinet/udp.h>
#include <netinet6/in6_var.h>
#include <netinet6/ip6_var.h>
#include <netinet/in_pcb.h>
#include <netinet/icmp6.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/nd6.h>
#include <netinet6/scope6_var.h>
#include <netinet6/ip6protosw.h>
#if IPSEC
#include <netinet6/ipsec.h>
#include <netinet6/ipsec6.h>
extern int ipsec_bypass;
#endif /* IPSEC */
#if DUMMYNET
#include <netinet/ip_dummynet.h>
#endif /* DUMMYNET */
/* we need it for NLOOP. */
#include "loop.h"
#if PF
#include <net/pfvar.h>
#endif /* PF */
#include <os/log.h>
struct ip6protosw *ip6_protox[IPPROTO_MAX];
static LCK_GRP_DECLARE(in6_ifaddr_rwlock_grp, "in6_ifaddr_rwlock");
LCK_RW_DECLARE(in6_ifaddr_rwlock, &in6_ifaddr_rwlock_grp);
/* Protected by in6_ifaddr_rwlock */
struct in6_ifaddrhead in6_ifaddrhead;
uint32_t in6_ifaddrlist_genid = 0;
struct in6_ifaddrhashhead * in6_ifaddrhashtbl;
uint32_t in6_ifaddrhmask;
#define IN6ADDR_NHASH 61
u_int32_t in6addr_nhash = 0; /* hash table size */
u_int32_t in6addr_hashp = 0; /* next largest prime */
#define IN6_IFSTAT_REQUIRE_ALIGNED_64(f) \
_CASSERT(!(offsetof(struct in6_ifstat, f) % sizeof (uint64_t)))
#define ICMP6_IFSTAT_REQUIRE_ALIGNED_64(f) \
_CASSERT(!(offsetof(struct icmp6_ifstat, f) % sizeof (uint64_t)))
struct ip6stat ip6stat;
LCK_ATTR_DECLARE(ip6_mutex_attr, 0, 0);
LCK_GRP_DECLARE(ip6_mutex_grp, "ip6");
LCK_MTX_DECLARE_ATTR(proxy6_lock, &ip6_mutex_grp, &ip6_mutex_attr);
LCK_MTX_DECLARE_ATTR(nd6_mutex_data, &ip6_mutex_grp, &ip6_mutex_attr);
extern int loopattach_done;
extern void addrsel_policy_init(void);
static int sysctl_reset_ip6_input_stats SYSCTL_HANDLER_ARGS;
static int sysctl_ip6_input_measure_bins SYSCTL_HANDLER_ARGS;
static int sysctl_ip6_input_getperf SYSCTL_HANDLER_ARGS;
static void ip6_init_delayed(void);
static int ip6_hopopts_input(u_int32_t *, u_int32_t *, struct mbuf **, int *);
static void in6_ifaddrhashtbl_init(void);
static struct m_tag *m_tag_kalloc_inet6(u_int32_t id, u_int16_t type, uint16_t len, int wait);
static void m_tag_kfree_inet6(struct m_tag *tag);
#if NSTF
extern void stfattach(void);
#endif /* NSTF */
SYSCTL_DECL(_net_inet6_ip6);
static uint32_t ip6_adj_clear_hwcksum = 0;
SYSCTL_UINT(_net_inet6_ip6, OID_AUTO, adj_clear_hwcksum,
CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_adj_clear_hwcksum, 0,
"Invalidate hwcksum info when adjusting length");
static uint32_t ip6_adj_partial_sum = 1;
SYSCTL_UINT(_net_inet6_ip6, OID_AUTO, adj_partial_sum,
CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_adj_partial_sum, 0,
"Perform partial sum adjustment of trailing bytes at IP layer");
static int ip6_input_measure = 0;
SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, input_perf,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
&ip6_input_measure, 0, sysctl_reset_ip6_input_stats, "I", "Do time measurement");
static uint64_t ip6_input_measure_bins = 0;
SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, input_perf_bins,
CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &ip6_input_measure_bins, 0,
sysctl_ip6_input_measure_bins, "I",
"bins for chaining performance data histogram");
static net_perf_t net_perf;
SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, input_perf_data,
CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
0, 0, sysctl_ip6_input_getperf, "S,net_perf",
"IP6 input performance data (struct net_perf, net/net_perf.h)");
/*
* ip6_checkinterface controls the receive side of the models for multihoming
* that are discussed in RFC 1122.
*
* sysctl_ip6_checkinterface values are:
* IP6_CHECKINTERFACE_WEAK_ES:
* This corresponds to the Weak End-System model where incoming packets from
* any interface are accepted provided the destination address of the incoming packet
* is assigned to some interface.
*
* IP6_CHECKINTERFACE_HYBRID_ES:
* The Hybrid End-System model use the Strong End-System for tunnel interfaces
* (ipsec and utun) and the weak End-System model for other interfaces families.
* This prevents a rogue middle box to probe for signs of TCP connections
* that use the tunnel interface.
*
* IP6_CHECKINTERFACE_STRONG_ES:
* The Strong model model requires the packet arrived on an interface that
* is assigned the destination address of the packet.
*
* Since the routing table and transmit implementation do not implement the Strong ES model,
* setting this to a value different from IP6_CHECKINTERFACE_WEAK_ES may lead to unexpected results.
*
* When forwarding is enabled, the system reverts to the Weak ES model as a router
* is expected by design to receive packets from several interfaces to the same address.
*/
#define IP6_CHECKINTERFACE_WEAK_ES 0
#define IP6_CHECKINTERFACE_HYBRID_ES 1
#define IP6_CHECKINTERFACE_STRONG_ES 2
static int ip6_checkinterface = IP6_CHECKINTERFACE_HYBRID_ES;
static int sysctl_ip6_checkinterface SYSCTL_HANDLER_ARGS;
SYSCTL_PROC(_net_inet6_ip6, OID_AUTO, check_interface,
CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED,
0, 0, sysctl_ip6_checkinterface, "I", "Verify packet arrives on correct interface");
#if (DEBUG || DEVELOPMENT)
#define IP6_CHECK_IFDEBUG 1
#else
#define IP6_CHECK_IFDEBUG 0
#endif /* (DEBUG || DEVELOPMENT) */
static int ip6_checkinterface_debug = IP6_CHECK_IFDEBUG;
SYSCTL_INT(_net_inet6_ip6, OID_AUTO, checkinterface_debug, CTLFLAG_RW | CTLFLAG_LOCKED,
&ip6_checkinterface_debug, IP6_CHECK_IFDEBUG, "");
typedef enum ip6_check_if_result {
IP6_CHECK_IF_NONE = 0,
IP6_CHECK_IF_OURS = 1,
IP6_CHECK_IF_DROP = 2,
IP6_CHECK_IF_FORWARD = 3
} ip6_check_if_result_t;
static ip6_check_if_result_t ip6_input_check_interface(struct mbuf *, struct ip6_hdr *, struct ifnet *, struct route_in6 *rin6, struct ifnet **);
/*
* On platforms which require strict alignment (currently for anything but
* i386 or x86_64 or arm64), check if the IP header pointer is 32-bit aligned; if not,
* copy the contents of the mbuf chain into a new chain, and free the original
* one. Create some head room in the first mbuf of the new chain, in case
* it's needed later on.
*
* RFC 2460 says that IPv6 headers are 64-bit aligned, but network interfaces
* mostly align to 32-bit boundaries. Care should be taken never to use 64-bit
* load/store operations on the fields in IPv6 headers.
*/
#if defined(__i386__) || defined(__x86_64__) || defined(__arm64__)
#define IP6_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { } while (0)
#else /* !__i386__ && !__x86_64__ && !__arm64__ */
#define IP6_HDR_ALIGNMENT_FIXUP(_m, _ifp, _action) do { \
if (!IP6_HDR_ALIGNED_P(mtod(_m, caddr_t))) { \
struct mbuf *_n; \
struct ifnet *__ifp = (_ifp); \
os_atomic_inc(&(__ifp)->if_alignerrs, relaxed); \
if (((_m)->m_flags & M_PKTHDR) && \
(_m)->m_pkthdr.pkt_hdr != NULL) \
(_m)->m_pkthdr.pkt_hdr = NULL; \
_n = m_defrag_offset(_m, max_linkhdr, M_NOWAIT); \
if (_n == NULL) { \
ip6stat.ip6s_toosmall++; \
m_freem(_m); \
(_m) = NULL; \
_action; \
} else { \
VERIFY(_n != (_m)); \
(_m) = _n; \
} \
} \
} while (0)
#endif /* !__i386__ && !__x86_64___ && !__arm64__ */
static void
ip6_proto_input(protocol_family_t protocol, mbuf_t packet)
{
#pragma unused(protocol)
#if INET
struct timeval start_tv;
if (ip6_input_measure) {
net_perf_start_time(&net_perf, &start_tv);
}
#endif /* INET */
ip6_input(packet);
#if INET
if (ip6_input_measure) {
net_perf_measure_time(&net_perf, &start_tv, 1);
net_perf_histogram(&net_perf, 1);
}
#endif /* INET */
}
/*
* IP6 initialization: fill in IP6 protocol switch table.
* All protocols not implemented in kernel go to raw IP6 protocol handler.
*/
void
ip6_init(struct ip6protosw *pp, struct domain *dp)
{
static int ip6_initialized = 0;
struct protosw *pr;
struct timeval tv;
int i;
domain_unguard_t unguard;
domain_proto_mtx_lock_assert_held();
VERIFY((pp->pr_flags & (PR_INITIALIZED | PR_ATTACHED)) == PR_ATTACHED);
_CASSERT((sizeof(struct ip6_hdr) +
sizeof(struct icmp6_hdr)) <= _MHLEN);
if (ip6_initialized) {
return;
}
ip6_initialized = 1;
eventhandler_lists_ctxt_init(&in6_evhdlr_ctxt);
(void)EVENTHANDLER_REGISTER(&in6_evhdlr_ctxt, in6_event,
in6_eventhdlr_callback, eventhandler_entry_dummy_arg,
EVENTHANDLER_PRI_ANY);
eventhandler_lists_ctxt_init(&in6_clat46_evhdlr_ctxt);
(void)EVENTHANDLER_REGISTER(&in6_clat46_evhdlr_ctxt, in6_clat46_event,
in6_clat46_eventhdlr_callback, eventhandler_entry_dummy_arg,
EVENTHANDLER_PRI_ANY);
for (i = 0; i < IN6_EVENT_MAX; i++) {
VERIFY(in6_event2kev_array[i].in6_event_code == i);
}
pr = pffindproto_locked(PF_INET6, IPPROTO_RAW, SOCK_RAW);
if (pr == NULL) {
panic("%s: Unable to find [PF_INET6,IPPROTO_RAW,SOCK_RAW]",
__func__);
/* NOTREACHED */
}
/* Initialize the entire ip6_protox[] array to IPPROTO_RAW. */
for (i = 0; i < IPPROTO_MAX; i++) {
ip6_protox[i] = (struct ip6protosw *)pr;
}
/*
* Cycle through IP protocols and put them into the appropriate place
* in ip6_protox[], skipping protocols IPPROTO_{IP,RAW}.
*/
VERIFY(dp == inet6domain && dp->dom_family == PF_INET6);
TAILQ_FOREACH(pr, &dp->dom_protosw, pr_entry) {
VERIFY(pr->pr_domain == dp);
if (pr->pr_protocol != 0 && pr->pr_protocol != IPPROTO_RAW) {
/* Be careful to only index valid IP protocols. */
if (pr->pr_protocol < IPPROTO_MAX) {
ip6_protox[pr->pr_protocol] =
(struct ip6protosw *)pr;
}
}
}
TAILQ_INIT(&in6_ifaddrhead);
in6_ifaddrhashtbl_init();
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_receive);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_hdrerr);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_toobig);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_noroute);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_addrerr);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_protounknown);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_truncated);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_discard);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_deliver);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_forward);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_request);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_discard);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_fragok);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_fragfail);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_fragcreat);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_reass_reqd);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_reass_ok);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_reass_fail);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mcast);
IN6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mcast);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_msg);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_error);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_dstunreach);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_adminprohib);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_timeexceed);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_paramprob);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_pkttoobig);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_echo);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_echoreply);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_routersolicit);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_routeradvert);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_neighborsolicit);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_neighboradvert);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_redirect);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mldquery);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mldreport);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_in_mlddone);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_msg);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_error);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_dstunreach);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_adminprohib);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_timeexceed);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_paramprob);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_pkttoobig);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_echo);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_echoreply);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_routersolicit);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_routeradvert);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_neighborsolicit);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_neighboradvert);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_redirect);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mldquery);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mldreport);
ICMP6_IFSTAT_REQUIRE_ALIGNED_64(ifs6_out_mlddone);
getmicrotime(&tv);
ip6_desync_factor =
(RandomULong() ^ tv.tv_usec) % MAX_TEMP_DESYNC_FACTOR;
PE_parse_boot_argn("in6_embedded_scope", &in6_embedded_scope, sizeof(in6_embedded_scope));
PE_parse_boot_argn("ip6_checkinterface", &i, sizeof(i));
switch (i) {
case IP6_CHECKINTERFACE_WEAK_ES:
case IP6_CHECKINTERFACE_HYBRID_ES:
case IP6_CHECKINTERFACE_STRONG_ES:
ip6_checkinterface = i;
break;
default:
break;
}
in6_ifaddr_init();
ip6_moptions_init();
nd6_init();
frag6_init();
icmp6_init(NULL, dp);
addrsel_policy_init();
/*
* P2P interfaces often route the local address to the loopback
* interface. At this point, lo0 hasn't been initialized yet, which
* means that we need to delay the IPv6 configuration of lo0.
*/
net_init_add(ip6_init_delayed);
unguard = domain_unguard_deploy();
i = proto_register_input(PF_INET6, ip6_proto_input, NULL, 0);
if (i != 0) {
panic("%s: failed to register PF_INET6 protocol: %d",
__func__, i);
/* NOTREACHED */
}
domain_unguard_release(unguard);
}
static void
ip6_init_delayed(void)
{
(void) in6_ifattach_prelim(lo_ifp);
/* timer for regeneranation of temporary addresses randomize ID */
timeout(in6_tmpaddrtimer, NULL,
(ip6_temp_preferred_lifetime - ip6_desync_factor -
ip6_temp_regen_advance) * hz);
#if NSTF
stfattach();
#endif /* NSTF */
}
static void
ip6_input_adjust(struct mbuf *m, struct ip6_hdr *ip6, uint32_t plen,
struct ifnet *inifp)
{
boolean_t adjust = TRUE;
uint32_t tot_len = sizeof(*ip6) + plen;
ASSERT(m_pktlen(m) > tot_len);
/*
* Invalidate hardware checksum info if ip6_adj_clear_hwcksum
* is set; useful to handle buggy drivers. Note that this
* should not be enabled by default, as we may get here due
* to link-layer padding.
*/
if (ip6_adj_clear_hwcksum &&
(m->m_pkthdr.csum_flags & CSUM_DATA_VALID) &&
!(inifp->if_flags & IFF_LOOPBACK) &&
!(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
m->m_pkthdr.csum_data = 0;
ip6stat.ip6s_adj_hwcsum_clr++;
}
/*
* If partial checksum information is available, subtract
* out the partial sum of postpended extraneous bytes, and
* update the checksum metadata accordingly. By doing it
* here, the upper layer transport only needs to adjust any
* prepended extraneous bytes (else it will do both.)
*/
if (ip6_adj_partial_sum &&
(m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PARTIAL)) ==
(CSUM_DATA_VALID | CSUM_PARTIAL)) {
m->m_pkthdr.csum_rx_val = m_adj_sum16(m,
m->m_pkthdr.csum_rx_start, m->m_pkthdr.csum_rx_start,
(tot_len - m->m_pkthdr.csum_rx_start),
m->m_pkthdr.csum_rx_val);
} else if ((m->m_pkthdr.csum_flags &
(CSUM_DATA_VALID | CSUM_PARTIAL)) ==
(CSUM_DATA_VALID | CSUM_PARTIAL)) {
/*
* If packet has partial checksum info and we decided not
* to subtract the partial sum of postpended extraneous
* bytes here (not the default case), leave that work to
* be handled by the other layers. For now, only TCP, UDP
* layers are capable of dealing with this. For all other
* protocols (including fragments), trim and ditch the
* partial sum as those layers might not implement partial
* checksumming (or adjustment) at all.
*/
if (ip6->ip6_nxt == IPPROTO_TCP ||
ip6->ip6_nxt == IPPROTO_UDP) {
adjust = FALSE;
} else {
m->m_pkthdr.csum_flags &= ~CSUM_DATA_VALID;
m->m_pkthdr.csum_data = 0;
ip6stat.ip6s_adj_hwcsum_clr++;
}
}
if (adjust) {
ip6stat.ip6s_adj++;
if (m->m_len == m->m_pkthdr.len) {
m->m_len = tot_len;
m->m_pkthdr.len = tot_len;
} else {
m_adj(m, tot_len - m->m_pkthdr.len);
}
}
}
static ip6_check_if_result_t
ip6_input_check_interface(struct mbuf *m, struct ip6_hdr *ip6, struct ifnet *inifp, struct route_in6 *rin6, struct ifnet **deliverifp)
{
struct in6_ifaddr *ia6 = NULL;
struct in6_addr tmp_dst = ip6->ip6_dst; /* copy to avoid unaligned access */
struct in6_ifaddr *best_ia6 = NULL;
uint32_t dst_ifscope = IFSCOPE_NONE;
ip6_check_if_result_t result = IP6_CHECK_IF_NONE;
*deliverifp = NULL;
if (m->m_pkthdr.pkt_flags & PKTF_IFAINFO) {
dst_ifscope = m->m_pkthdr.dst_ifindex;
} else {
dst_ifscope = inifp->if_index;
}
/*
* Check for exact addresses in the hash bucket.
*/
lck_rw_lock_shared(&in6_ifaddr_rwlock);
TAILQ_FOREACH(ia6, IN6ADDR_HASH(&tmp_dst), ia6_hash) {
/*
* TODO: should we accept loopback
*/
if (in6_are_addr_equal_scoped(&ia6->ia_addr.sin6_addr, &tmp_dst, ia6->ia_ifp->if_index, dst_ifscope)) {
if ((ia6->ia6_flags & (IN6_IFF_NOTREADY | IN6_IFF_CLAT46))) {
continue;
}
best_ia6 = ia6;
if (ia6->ia_ifp == inifp) {
/*
* TODO: should we also accept locally originated packets
* or from loopback ???
*/
break;
}
/*
* Continue the loop in case there's a exact match with another
* interface
*/
}
}
if (best_ia6 != NULL) {
if (best_ia6->ia_ifp != inifp && ip6_forwarding == 0 &&
((ip6_checkinterface == IP6_CHECKINTERFACE_HYBRID_ES &&
(best_ia6->ia_ifp->if_family == IFNET_FAMILY_IPSEC ||
best_ia6->ia_ifp->if_family == IFNET_FAMILY_UTUN)) ||
ip6_checkinterface == IP6_CHECKINTERFACE_STRONG_ES)) {
/*
* Drop when interface address check is strict and forwarding
* is disabled
*/
result = IP6_CHECK_IF_DROP;
} else {
result = IP6_CHECK_IF_OURS;
*deliverifp = best_ia6->ia_ifp;
ip6_setdstifaddr_info(m, 0, best_ia6);
ip6_setsrcifaddr_info(m, best_ia6->ia_ifp->if_index, NULL);
}
}
lck_rw_done(&in6_ifaddr_rwlock);
if (result == IP6_CHECK_IF_NONE) {
/*
* Slow path: route lookup.
*/
struct sockaddr_in6 *dst6;
dst6 = SIN6(&rin6->ro_dst);
dst6->sin6_len = sizeof(struct sockaddr_in6);
dst6->sin6_family = AF_INET6;
dst6->sin6_addr = ip6->ip6_dst;
if (!in6_embedded_scope && IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
dst6->sin6_scope_id = dst_ifscope;
}
rtalloc_scoped_ign((struct route *)rin6,
RTF_PRCLONING, IFSCOPE_NONE);
if (rin6->ro_rt != NULL) {
RT_LOCK_SPIN(rin6->ro_rt);
}
#define rt6_key(r) (SIN6((r)->rt_nodes->rn_key))
/*
* Accept the packet if the forwarding interface to the destination
* according to the routing table is the loopback interface,
* unless the associated route has a gateway.
* Note that this approach causes to accept a packet if there is a
* route to the loopback interface for the destination of the packet.
* But we think it's even useful in some situations, e.g. when using
* a special daemon which wants to intercept the packet.
*
* XXX: some OSes automatically make a cloned route for the destination
* of an outgoing packet. If the outgoing interface of the packet
* is a loopback one, the kernel would consider the packet to be
* accepted, even if we have no such address assinged on the interface.
* We check the cloned flag of the route entry to reject such cases,
* assuming that route entries for our own addresses are not made by
* cloning (it should be true because in6_addloop explicitly installs
* the host route). However, we might have to do an explicit check
* while it would be less efficient. Or, should we rather install a
* reject route for such a case?
*/
if (rin6->ro_rt != NULL &&
(rin6->ro_rt->rt_flags & (RTF_HOST | RTF_GATEWAY)) == RTF_HOST &&
#if RTF_WASCLONED
!(rin6->ro_rt->rt_flags & RTF_WASCLONED) &&
#endif
rin6->ro_rt->rt_ifp->if_type == IFT_LOOP) {
ia6 = (struct in6_ifaddr *)rin6->ro_rt->rt_ifa;
/*
* Packets to a tentative, duplicated, or somehow invalid
* address must not be accepted.
*
* For performance, test without acquiring the address lock;
* a lot of things in the address are set once and never
* changed (e.g. ia_ifp.)
*/
if (!(ia6->ia6_flags & IN6_IFF_NOTREADY)) {
/* this address is ready */
result = IP6_CHECK_IF_OURS;
*deliverifp = ia6->ia_ifp; /* correct? */
/*
* record dst address information into mbuf.
*/
(void) ip6_setdstifaddr_info(m, 0, ia6);
(void) ip6_setsrcifaddr_info(m, ia6->ia_ifp->if_index, NULL);
}
}
if (rin6->ro_rt != NULL) {
RT_UNLOCK(rin6->ro_rt);
}
}
if (result == IP6_CHECK_IF_NONE) {
if (ip6_forwarding == 0) {
result = IP6_CHECK_IF_DROP;
} else {
result = IP6_CHECK_IF_FORWARD;
ip6_setdstifaddr_info(m, inifp->if_index, NULL);
ip6_setsrcifaddr_info(m, inifp->if_index, NULL);
}
}
if (result == IP6_CHECK_IF_OURS && *deliverifp != inifp) {
ASSERT(*deliverifp != NULL);
ip6stat.ip6s_rcv_if_weak_match++;
/* Logging is too noisy when forwarding is enabled */
if (ip6_checkinterface_debug != IP6_CHECKINTERFACE_WEAK_ES && ip6_forwarding != 0) {
char src_str[MAX_IPv6_STR_LEN];
char dst_str[MAX_IPv6_STR_LEN];
inet_ntop(AF_INET6, &ip6->ip6_src, src_str, sizeof(src_str));
inet_ntop(AF_INET6, &ip6->ip6_dst, dst_str, sizeof(dst_str));
os_log_info(OS_LOG_DEFAULT,
"%s: weak ES interface match to %s for packet from %s to %s proto %u received via %s",
__func__, (*deliverifp)->if_xname, src_str, dst_str, ip6->ip6_nxt, inifp->if_xname);
}
} else if (result == IP6_CHECK_IF_DROP) {
ip6stat.ip6s_rcv_if_no_match++;
if (ip6_checkinterface_debug > 0) {
char src_str[MAX_IPv6_STR_LEN];
char dst_str[MAX_IPv6_STR_LEN];
inet_ntop(AF_INET6, &ip6->ip6_src, src_str, sizeof(src_str));
inet_ntop(AF_INET6, &ip6->ip6_dst, dst_str, sizeof(dst_str));
os_log(OS_LOG_DEFAULT,
"%s: no interface match for packet from %s to %s proto %u received via %s",
__func__, src_str, dst_str, ip6->ip6_nxt, inifp->if_xname);
}
}
return result;
}
void
ip6_input(struct mbuf *m)
{
struct ip6_hdr *ip6;
int off = sizeof(struct ip6_hdr), nest;
u_int32_t plen;
u_int32_t rtalert = ~0;
int nxt = 0, ours = 0;
struct ifnet *inifp, *deliverifp = NULL;
ipfilter_t inject_ipfref = NULL;
int seen = 1;
#if DUMMYNET
struct m_tag *tag;
struct ip_fw_args args = {};
#endif /* DUMMYNET */
struct route_in6 rin6 = {};
/*
* Check if the packet we received is valid after interface filter
* processing
*/
MBUF_INPUT_CHECK(m, m->m_pkthdr.rcvif);
inifp = m->m_pkthdr.rcvif;
VERIFY(inifp != NULL);
/* Perform IP header alignment fixup, if needed */
IP6_HDR_ALIGNMENT_FIXUP(m, inifp, return );
m->m_pkthdr.pkt_flags &= ~PKTF_FORWARDED;
#if IPSEC
/*
* should the inner packet be considered authentic?
* see comment in ah4_input().
*/
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
#endif /* IPSEC */
/*
* make sure we don't have onion peering information into m_aux.
*/
ip6_delaux(m);
#if DUMMYNET
if ((tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
KERNEL_TAG_TYPE_DUMMYNET)) != NULL) {
struct dn_pkt_tag *dn_tag;
dn_tag = (struct dn_pkt_tag *)(tag->m_tag_data);
args.fwa_pf_rule = dn_tag->dn_pf_rule;
m_tag_delete(m, tag);
}
if (args.fwa_pf_rule) {
ip6 = mtod(m, struct ip6_hdr *); /* In case PF got disabled */
goto check_with_pf;
}
#endif /* DUMMYNET */
/*
* No need to process packet twice if we've already seen it.
*/
inject_ipfref = ipf_get_inject_filter(m);
if (inject_ipfref != NULL) {
ip6 = mtod(m, struct ip6_hdr *);
nxt = ip6->ip6_nxt;
seen = 0;
goto injectit;
} else {
seen = 1;
}
if (__improbable(m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT)) {
if_ports_used_match_mbuf(inifp, PF_INET6, m);
}
/*
* mbuf statistics
*/
if (m->m_flags & M_EXT) {
if (m->m_next != NULL) {
ip6stat.ip6s_mext2m++;
} else {
ip6stat.ip6s_mext1++;
}
} else {
#define M2MMAX (sizeof (ip6stat.ip6s_m2m) / sizeof (ip6stat.ip6s_m2m[0]))
if (m->m_next != NULL) {
if (m->m_pkthdr.pkt_flags & PKTF_LOOP) {
/* XXX */
ip6stat.ip6s_m2m[ifnet_index(lo_ifp)]++;
} else if (inifp->if_index < M2MMAX) {
ip6stat.ip6s_m2m[inifp->if_index]++;
} else {
ip6stat.ip6s_m2m[0]++;
}
} else {
ip6stat.ip6s_m1++;
}
#undef M2MMAX
}
/*
* Drop the packet if IPv6 operation is disabled on the interface.
*/
if (inifp->if_eflags & IFEF_IPV6_DISABLED) {
goto bad;
}
in6_ifstat_inc_na(inifp, ifs6_in_receive);
ip6stat.ip6s_total++;
/*
* L2 bridge code and some other code can return mbuf chain
* that does not conform to KAME requirement. too bad.
* XXX: fails to join if interface MTU > MCLBYTES. jumbogram?
*/
if (m->m_next != NULL && m->m_pkthdr.len < MCLBYTES) {
struct mbuf *n;
MGETHDR(n, M_DONTWAIT, MT_HEADER); /* MAC-OK */
if (n) {
M_COPY_PKTHDR(n, m);
}
if (n && m->m_pkthdr.len > MHLEN) {
MCLGET(n, M_DONTWAIT);
if ((n->m_flags & M_EXT) == 0) {
m_freem(n);
n = NULL;
}
}
if (n == NULL) {
goto bad;
}
m_copydata(m, 0, m->m_pkthdr.len, mtod(n, caddr_t));
n->m_len = m->m_pkthdr.len;
m_freem(m);
m = n;
}
IP6_EXTHDR_CHECK(m, 0, sizeof(struct ip6_hdr), { goto done; });
if (m->m_len < sizeof(struct ip6_hdr)) {
if ((m = m_pullup(m, sizeof(struct ip6_hdr))) == 0) {
ip6stat.ip6s_toosmall++;
in6_ifstat_inc(inifp, ifs6_in_hdrerr);
goto done;
}
}
ip6 = mtod(m, struct ip6_hdr *);
if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
ip6stat.ip6s_badvers++;
in6_ifstat_inc(inifp, ifs6_in_hdrerr);
goto bad;
}
ip6stat.ip6s_nxthist[ip6->ip6_nxt]++;
/*
* Check against address spoofing/corruption.
*/
if (!(m->m_pkthdr.pkt_flags & PKTF_LOOP) &&
IN6_IS_ADDR_LOOPBACK(&ip6->ip6_src)) {
ip6stat.ip6s_badscope++;
in6_ifstat_inc(inifp, ifs6_in_addrerr);
goto bad;
}
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_src) ||
IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_dst)) {
/*
* XXX: "badscope" is not very suitable for a multicast source.
*/
ip6stat.ip6s_badscope++;
in6_ifstat_inc(inifp, ifs6_in_addrerr);
goto bad;
}
if (IN6_IS_ADDR_MC_INTFACELOCAL(&ip6->ip6_dst) &&
!(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
/*
* In this case, the packet should come from the loopback
* interface. However, we cannot just check the if_flags,
* because ip6_mloopback() passes the "actual" interface
* as the outgoing/incoming interface.
*/
ip6stat.ip6s_badscope++;
in6_ifstat_inc(inifp, ifs6_in_addrerr);
goto bad;
}
/*
* The following check is not documented in specs. A malicious
* party may be able to use IPv4 mapped addr to confuse tcp/udp stack
* and bypass security checks (act as if it was from 127.0.0.1 by using
* IPv6 src ::ffff:127.0.0.1). Be cautious.
*
* This check chokes if we are in an SIIT cloud. As none of BSDs
* support IPv4-less kernel compilation, we cannot support SIIT
* environment at all. So, it makes more sense for us to reject any
* malicious packets for non-SIIT environment, than try to do a
* partial support for SIIT environment.
*/
if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
ip6stat.ip6s_badscope++;
in6_ifstat_inc(inifp, ifs6_in_addrerr);
goto bad;
}
if (((ntohl(ip6->ip6_flow & IPV6_FLOW_ECN_MASK) >> 20) & IPTOS_ECN_ECT1) == IPTOS_ECN_ECT1) {
m->m_pkthdr.pkt_ext_flags |= PKTF_EXT_L4S;
}
#if 0
/*
* Reject packets with IPv4 compatible addresses (auto tunnel).
*
* The code forbids auto tunnel relay case in RFC1933 (the check is
* stronger than RFC1933). We may want to re-enable it if mech-xx
* is revised to forbid relaying case.
*/
if (IN6_IS_ADDR_V4COMPAT(&ip6->ip6_src) ||
IN6_IS_ADDR_V4COMPAT(&ip6->ip6_dst)) {
ip6stat.ip6s_badscope++;
in6_ifstat_inc(inifp, ifs6_in_addrerr);
goto bad;
}
#endif
/*
* Naively assume we can attribute inbound data to the route we would
* use to send to this destination. Asymetric routing breaks this
* assumption, but it still allows us to account for traffic from
* a remote node in the routing table.
* this has a very significant performance impact so we bypass
* if nstat_collect is disabled. We may also bypass if the
* protocol is tcp in the future because tcp will have a route that
* we can use to attribute the data to. That does mean we would not
* account for forwarded tcp traffic.
*/
if (nstat_collect) {
struct rtentry *rte =
ifnet_cached_rtlookup_inet6(inifp, &ip6->ip6_src);
if (rte != NULL) {
nstat_route_rx(rte, 1, m->m_pkthdr.len, 0);
rtfree(rte);
}
}
#if DUMMYNET
check_with_pf:
#endif /* DUMMYNET */
#if PF
/* Invoke inbound packet filter */
if (PF_IS_ENABLED) {
int error;
#if DUMMYNET
error = pf_af_hook(inifp, NULL, &m, AF_INET6, TRUE, &args);
#else /* !DUMMYNET */
error = pf_af_hook(inifp, NULL, &m, AF_INET6, TRUE, NULL);
#endif /* !DUMMYNET */
if (error != 0 || m == NULL) {
if (m != NULL) {
panic("%s: unexpected packet %p",
__func__, m);
/* NOTREACHED */
}
/* Already freed by callee */
goto done;
}
ip6 = mtod(m, struct ip6_hdr *);
}
#endif /* PF */
/* drop packets if interface ID portion is already filled */
if (!(inifp->if_flags & IFF_LOOPBACK) &&
!(m->m_pkthdr.pkt_flags & PKTF_LOOP)) {
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src) &&
ip6->ip6_src.s6_addr16[1]) {
ip6stat.ip6s_badscope++;
goto bad;
}
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst) &&
ip6->ip6_dst.s6_addr16[1]) {
ip6stat.ip6s_badscope++;
goto bad;
}
}
if ((m->m_pkthdr.pkt_flags & PKTF_IFAINFO) != 0 && in6_embedded_scope) {
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
ip6->ip6_src.s6_addr16[1] =
htons(m->m_pkthdr.src_ifindex);
}
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
ip6->ip6_dst.s6_addr16[1] =
htons(m->m_pkthdr.dst_ifindex);
}
} else if (in6_embedded_scope) {
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
ip6->ip6_src.s6_addr16[1] = htons(inifp->if_index);
}
if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) {
ip6->ip6_dst.s6_addr16[1] = htons(inifp->if_index);
}
}
/*
* Multicast check
*/
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
struct in6_multi *in6m = NULL;
in6_ifstat_inc_na(inifp, ifs6_in_mcast);
/*
* See if we belong to the destination multicast group on the
* arrival interface.
*/
in6_multihead_lock_shared();
IN6_LOOKUP_MULTI(&ip6->ip6_dst, inifp, in6m);
in6_multihead_lock_done();
if (in6m != NULL) {
IN6M_REMREF(in6m);
ours = 1;
} else if (!nd6_prproxy) {
ip6stat.ip6s_notmember++;
ip6stat.ip6s_cantforward++;
in6_ifstat_inc(inifp, ifs6_in_discard);
goto bad;
}
deliverifp = inifp;
/*
* record dst address information into mbuf, if we don't have one yet.
* note that we are unable to record it, if the address is not listed
* as our interface address (e.g. multicast addresses, etc.)
*/
if (deliverifp != NULL) {
struct in6_ifaddr *ia6 = NULL;
ia6 = in6_ifawithifp(deliverifp, &ip6->ip6_dst);
if (ia6 != NULL) {
(void) ip6_setdstifaddr_info(m, 0, ia6);
(void) ip6_setsrcifaddr_info(m, ia6->ia_ifp->if_index, NULL);
ifa_remref(&ia6->ia_ifa);
} else {
(void) ip6_setdstifaddr_info(m, inifp->if_index, NULL);
(void) ip6_setsrcifaddr_info(m, inifp->if_index, NULL);
}
}
goto hbhcheck;
} else {
/*
* Unicast check
*/
ip6_check_if_result_t check_if_result = IP6_CHECK_IF_NONE;
check_if_result = ip6_input_check_interface(m, ip6, inifp, &rin6, &deliverifp);
ASSERT(check_if_result != IP6_CHECK_IF_NONE);
if (check_if_result == IP6_CHECK_IF_OURS) {
ours = 1;
goto hbhcheck;
} else if (check_if_result == IP6_CHECK_IF_DROP) {
goto bad;
}
}
/*
* Now there is no reason to process the packet if it's not our own
* and we're not a router.
*/
if (!ip6_forwarding) {
ip6stat.ip6s_cantforward++;
in6_ifstat_inc(inifp, ifs6_in_discard);
/*
* Raise a kernel event if the packet received on cellular
* interface is not intended for local host.
* For now limit it to ICMPv6 packets.
*/
if (inifp->if_type == IFT_CELLULAR &&
ip6->ip6_nxt == IPPROTO_ICMPV6) {
in6_ifstat_inc(inifp, ifs6_cantfoward_icmp6);
}
goto bad;
}
hbhcheck:
/*
* Process Hop-by-Hop options header if it's contained.
* m may be modified in ip6_hopopts_input().
* If a JumboPayload option is included, plen will also be modified.
*/
plen = (u_int32_t)ntohs(ip6->ip6_plen);
if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
struct ip6_hbh *hbh;
/*
* Mark the packet to imply that HBH option has been checked.
* This can only be true is the packet came in unfragmented
* or if the option is in the first fragment
*/
m->m_pkthdr.pkt_flags |= PKTF_HBH_CHKED;
if (ip6_hopopts_input(&plen, &rtalert, &m, &off)) {
#if 0 /* touches NULL pointer */
in6_ifstat_inc(inifp, ifs6_in_discard);
#endif
goto done; /* m have already been freed */
}
/* adjust pointer */
ip6 = mtod(m, struct ip6_hdr *);
/*
* if the payload length field is 0 and the next header field
* indicates Hop-by-Hop Options header, then a Jumbo Payload
* option MUST be included.
*/
if (ip6->ip6_plen == 0 && plen == 0) {
/*
* Note that if a valid jumbo payload option is
* contained, ip6_hopopts_input() must set a valid
* (non-zero) payload length to the variable plen.
*/
ip6stat.ip6s_badoptions++;
in6_ifstat_inc(inifp, ifs6_in_discard);
in6_ifstat_inc(inifp, ifs6_in_hdrerr);
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_HEADER,
(int)((caddr_t)&ip6->ip6_plen - (caddr_t)ip6));
goto done;
}
/* ip6_hopopts_input() ensures that mbuf is contiguous */
hbh = (struct ip6_hbh *)(ip6 + 1);
nxt = hbh->ip6h_nxt;
/*
* If we are acting as a router and the packet contains a
* router alert option, see if we know the option value.
* Currently, we only support the option value for MLD, in which
* case we should pass the packet to the multicast routing
* daemon.
*/
if (rtalert != ~0 && ip6_forwarding) {
switch (rtalert) {
case IP6OPT_RTALERT_MLD:
ours = 1;
break;
default:
/*
* RFC2711 requires unrecognized values must be
* silently ignored.
*/
break;
}
}
} else {
nxt = ip6->ip6_nxt;
}
/*
* Check that the amount of data in the buffers
* is as at least much as the IPv6 header would have us expect.
* Trim mbufs if longer than we expect.
* Drop packet if shorter than we expect.
*/
if (m->m_pkthdr.len - sizeof(struct ip6_hdr) < plen) {
ip6stat.ip6s_tooshort++;
in6_ifstat_inc(inifp, ifs6_in_truncated);
goto bad;
}
if (m->m_pkthdr.len > sizeof(struct ip6_hdr) + plen) {
ip6_input_adjust(m, ip6, plen, inifp);
}
/*
* Forward if desirable.
*/
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)) {
if (!ours && nd6_prproxy) {
/*
* If this isn't for us, this might be a Neighbor
* Solicitation (dst is solicited-node multicast)
* against an address in one of the proxied prefixes;
* if so, claim the packet and let icmp6_input()
* handle the rest.
*/
ours = nd6_prproxy_isours(m, ip6, NULL, IFSCOPE_NONE);
VERIFY(!ours ||
(m->m_pkthdr.pkt_flags & PKTF_PROXY_DST));
}
if (!ours) {
goto bad;
}
} else if (!ours) {
/*
* The unicast forwarding function might return the packet
* if we are proxying prefix(es), and if the packet is an
* ICMPv6 packet that has failed the zone checks, but is
* targetted towards a proxied address (this is optimized by
* way of RTF_PROXY test.) If so, claim the packet as ours
* and let icmp6_input() handle the rest. The packet's hop
* limit value is kept intact (it's not decremented). This
* is for supporting Neighbor Unreachability Detection between
* proxied nodes on different links (src is link-local, dst
* is target address.)
*/
if ((m = ip6_forward(m, &rin6, 0)) == NULL) {
goto done;
}
VERIFY(rin6.ro_rt != NULL);
VERIFY(m->m_pkthdr.pkt_flags & PKTF_PROXY_DST);
deliverifp = rin6.ro_rt->rt_ifp;
ours = 1;
}
ip6 = mtod(m, struct ip6_hdr *);
/*
* Malicious party may be able to use IPv4 mapped addr to confuse
* tcp/udp stack and bypass security checks (act as if it was from
* 127.0.0.1 by using IPv6 src ::ffff:127.0.0.1). Be cautious.
*
* For SIIT end node behavior, you may want to disable the check.
* However, you will become vulnerable to attacks using IPv4 mapped
* source.
*/
if (IN6_IS_ADDR_V4MAPPED(&ip6->ip6_src) ||
IN6_IS_ADDR_V4MAPPED(&ip6->ip6_dst)) {
ip6stat.ip6s_badscope++;
in6_ifstat_inc(inifp, ifs6_in_addrerr);
goto bad;
}
/*
* Tell launch routine the next header
*/
ip6stat.ip6s_delivered++;
in6_ifstat_inc_na(deliverifp, ifs6_in_deliver);
injectit:
nest = 0;
/*
* Perform IP header alignment fixup again, if needed. Note that
* we do it once for the outermost protocol, and we assume each
* protocol handler wouldn't mess with the alignment afterwards.
*/
IP6_HDR_ALIGNMENT_FIXUP(m, inifp, return );
while (nxt != IPPROTO_DONE) {
struct ipfilter *filter;
int (*pr_input)(struct mbuf **, int *, int);
/*
* This would imply either IPPROTO_HOPOPTS was not the first
* option or it did not come in the first fragment.
*/
if (nxt == IPPROTO_HOPOPTS &&
(m->m_pkthdr.pkt_flags & PKTF_HBH_CHKED) == 0) {
/*
* This implies that HBH option was not contained
* in the first fragment
*/
ip6stat.ip6s_badoptions++;
goto bad;
}
if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
ip6stat.ip6s_toomanyhdr++;
goto bad;
}
/*
* protection against faulty packet - there should be
* more sanity checks in header chain processing.
*/
if (m->m_pkthdr.len < off) {
ip6stat.ip6s_tooshort++;
in6_ifstat_inc(inifp, ifs6_in_truncated);
goto bad;
}
#if IPSEC
/*
* enforce IPsec policy checking if we are seeing last header.
* note that we do not visit this with protocols with pcb layer
* code - like udp/tcp/raw ip.
*/
if ((ipsec_bypass == 0) &&
(ip6_protox[nxt]->pr_flags & PR_LASTHDR) != 0) {
if (ipsec6_in_reject(m, NULL)) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio);
goto bad;
}
}
#endif /* IPSEC */
/*
* Call IP filter
*/
if (!TAILQ_EMPTY(&ipv6_filters) && !IFNET_IS_INTCOPROC(inifp)) {
ipf_ref();
TAILQ_FOREACH(filter, &ipv6_filters, ipf_link) {
if (seen == 0) {
if ((struct ipfilter *)inject_ipfref ==
filter) {
seen = 1;
}
} else if (filter->ipf_filter.ipf_input) {
errno_t result;
result = filter->ipf_filter.ipf_input(
filter->ipf_filter.cookie,
(mbuf_t *)&m, off, (uint8_t)nxt);
if (result == EJUSTRETURN) {
ipf_unref();
goto done;
}
if (result != 0) {
ipf_unref();
goto bad;
}
}
}
ipf_unref();
}
DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
struct ip6_hdr *, ip6, struct ifnet *, inifp,
struct ip *, NULL, struct ip6_hdr *, ip6);
if ((pr_input = ip6_protox[nxt]->pr_input) == NULL) {
m_freem(m);
m = NULL;
nxt = IPPROTO_DONE;
} else if (!(ip6_protox[nxt]->pr_flags & PR_PROTOLOCK)) {
lck_mtx_lock(inet6_domain_mutex);
nxt = pr_input(&m, &off, nxt);
lck_mtx_unlock(inet6_domain_mutex);
} else {
nxt = pr_input(&m, &off, nxt);
}
}
done:
ROUTE_RELEASE(&rin6);
return;
bad:
m_freem(m);
goto done;
}
void
ip6_setsrcifaddr_info(struct mbuf *m, uint32_t src_idx, struct in6_ifaddr *ia6)
{
VERIFY(m->m_flags & M_PKTHDR);
m->m_pkthdr.pkt_ext_flags &= ~PKTF_EXT_OUTPUT_SCOPE;
/*
* If the source ifaddr is specified, pick up the information
* from there; otherwise just grab the passed-in ifindex as the
* caller may not have the ifaddr available.
*/
if (ia6 != NULL) {
m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
m->m_pkthdr.src_ifindex = ia6->ia_ifp->if_index;
/* See IN6_IFF comments in in6_var.h */
m->m_pkthdr.src_iff = (ia6->ia6_flags & 0xffff);
} else {
m->m_pkthdr.src_iff = 0;
m->m_pkthdr.src_ifindex = (uint16_t)src_idx;
if (src_idx != 0) {
m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
}
}
}
void
ip6_setdstifaddr_info(struct mbuf *m, uint32_t dst_idx, struct in6_ifaddr *ia6)
{
VERIFY(m->m_flags & M_PKTHDR);
m->m_pkthdr.pkt_ext_flags &= ~PKTF_EXT_OUTPUT_SCOPE;
/*
* If the destination ifaddr is specified, pick up the information
* from there; otherwise just grab the passed-in ifindex as the
* caller may not have the ifaddr available.
*/
if (ia6 != NULL) {
m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
m->m_pkthdr.dst_ifindex = ia6->ia_ifp->if_index;
/* See IN6_IFF comments in in6_var.h */
m->m_pkthdr.dst_iff = (ia6->ia6_flags & 0xffff);
} else {
m->m_pkthdr.dst_iff = 0;
m->m_pkthdr.dst_ifindex = (uint16_t)dst_idx;
if (dst_idx != 0) {
m->m_pkthdr.pkt_flags |= PKTF_IFAINFO;
}
}
}
int
ip6_getsrcifaddr_info(struct mbuf *m, uint32_t *src_idx, uint32_t *ia6f)
{
VERIFY(m->m_flags & M_PKTHDR);
if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) {
return -1;
}
if (src_idx != NULL) {
*src_idx = m->m_pkthdr.src_ifindex;
}
if (ia6f != NULL) {
*ia6f = m->m_pkthdr.src_iff;
}
return 0;
}
int
ip6_getdstifaddr_info(struct mbuf *m, uint32_t *dst_idx, uint32_t *ia6f)
{
VERIFY(m->m_flags & M_PKTHDR);
if (!(m->m_pkthdr.pkt_flags & PKTF_IFAINFO)) {
return -1;
}
if (dst_idx != NULL) {
*dst_idx = m->m_pkthdr.dst_ifindex;
}
if (ia6f != NULL) {
*ia6f = m->m_pkthdr.dst_iff;
}
return 0;
}
uint32_t
ip6_input_getsrcifscope(struct mbuf *m)
{
VERIFY(m->m_flags & M_PKTHDR);
if (m->m_pkthdr.rcvif != NULL) {
return m->m_pkthdr.rcvif->if_index;
}
uint32_t src_ifscope = IFSCOPE_NONE;
ip6_getsrcifaddr_info(m, &src_ifscope, NULL);
return src_ifscope;
}
uint32_t
ip6_input_getdstifscope(struct mbuf *m)
{
VERIFY(m->m_flags & M_PKTHDR);
if (m->m_pkthdr.rcvif != NULL) {
return m->m_pkthdr.rcvif->if_index;
}
uint32_t dst_ifscope = IFSCOPE_NONE;
ip6_getdstifaddr_info(m, &dst_ifscope, NULL);
return dst_ifscope;
}
/*
* Hop-by-Hop options header processing. If a valid jumbo payload option is
* included, the real payload length will be stored in plenp.
*/
static int
ip6_hopopts_input(uint32_t *plenp, uint32_t *rtalertp, struct mbuf **mp,
int *offp)
{
struct mbuf *m = *mp;
int off = *offp, hbhlen;
struct ip6_hbh *hbh;
u_int8_t *opt;
/* validation of the length of the header */
IP6_EXTHDR_CHECK(m, off, sizeof(*hbh), return (-1));
hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
hbhlen = (hbh->ip6h_len + 1) << 3;
IP6_EXTHDR_CHECK(m, off, hbhlen, return (-1));
hbh = (struct ip6_hbh *)(mtod(m, caddr_t) + off);
off += hbhlen;
hbhlen -= sizeof(struct ip6_hbh);
opt = (u_int8_t *)hbh + sizeof(struct ip6_hbh);
if (ip6_process_hopopts(m, (u_int8_t *)hbh + sizeof(struct ip6_hbh),
hbhlen, rtalertp, plenp) < 0) {
return -1;
}
*offp = off;
*mp = m;
return 0;
}
/*
* Search header for all Hop-by-hop options and process each option.
* This function is separate from ip6_hopopts_input() in order to
* handle a case where the sending node itself process its hop-by-hop
* options header. In such a case, the function is called from ip6_output().
*
* The function assumes that hbh header is located right after the IPv6 header
* (RFC2460 p7), opthead is pointer into data content in m, and opthead to
* opthead + hbhlen is located in continuous memory region.
*/
int
ip6_process_hopopts(struct mbuf *m, u_int8_t *opthead, int hbhlen,
u_int32_t *rtalertp, u_int32_t *plenp)
{
struct ip6_hdr *ip6;
int optlen = 0;
u_int8_t *opt = opthead;
u_int16_t rtalert_val;
u_int32_t jumboplen;
const int erroff = sizeof(struct ip6_hdr) + sizeof(struct ip6_hbh);
for (; hbhlen > 0; hbhlen -= optlen, opt += optlen) {
switch (*opt) {
case IP6OPT_PAD1:
optlen = 1;
break;
case IP6OPT_PADN:
if (hbhlen < IP6OPT_MINLEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
optlen = *(opt + 1) + 2;
break;
case IP6OPT_ROUTER_ALERT:
/* XXX may need check for alignment */
if (hbhlen < IP6OPT_RTALERT_LEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
if (*(opt + 1) != IP6OPT_RTALERT_LEN - 2) {
/* XXX stat */
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
(int)(erroff + opt + 1 - opthead));
return -1;
}
optlen = IP6OPT_RTALERT_LEN;
bcopy((caddr_t)(opt + 2), (caddr_t)&rtalert_val, 2);
*rtalertp = ntohs(rtalert_val);
break;
case IP6OPT_JUMBO:
/* XXX may need check for alignment */
if (hbhlen < IP6OPT_JUMBO_LEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
if (*(opt + 1) != IP6OPT_JUMBO_LEN - 2) {
/* XXX stat */
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
(int)(erroff + opt + 1 - opthead));
return -1;
}
optlen = IP6OPT_JUMBO_LEN;
/*
* IPv6 packets that have non 0 payload length
* must not contain a jumbo payload option.
*/
ip6 = mtod(m, struct ip6_hdr *);
if (ip6->ip6_plen) {
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
(int)(erroff + opt - opthead));
return -1;
}
/*
* We may see jumbolen in unaligned location, so
* we'd need to perform bcopy().
*/
bcopy(opt + 2, &jumboplen, sizeof(jumboplen));
jumboplen = (u_int32_t)htonl(jumboplen);
#if 1
/*
* if there are multiple jumbo payload options,
* *plenp will be non-zero and the packet will be
* rejected.
* the behavior may need some debate in ipngwg -
* multiple options does not make sense, however,
* there's no explicit mention in specification.
*/
if (*plenp != 0) {
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
(int)(erroff + opt + 2 - opthead));
return -1;
}
#endif
/*
* jumbo payload length must be larger than 65535.
*/
if (jumboplen <= IPV6_MAXPACKET) {
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_HEADER,
(int)(erroff + opt + 2 - opthead));
return -1;
}
*plenp = jumboplen;
break;
default: /* unknown option */
if (hbhlen < IP6OPT_MINLEN) {
ip6stat.ip6s_toosmall++;
goto bad;
}
optlen = ip6_unknown_opt(opt, m,
erroff + opt - opthead);
if (optlen == -1) {
return -1;
}
optlen += 2;
break;
}
}
return 0;
bad:
m_freem(m);
return -1;
}
/*
* Unknown option processing.
* The third argument `off' is the offset from the IPv6 header to the option,
* which is necessary if the IPv6 header the and option header and IPv6 header
* is not continuous in order to return an ICMPv6 error.
*/
int
ip6_unknown_opt(uint8_t *optp, struct mbuf *m, size_t off)
{
struct ip6_hdr *ip6;
switch (IP6OPT_TYPE(*optp)) {
case IP6OPT_TYPE_SKIP: /* ignore the option */
return (int)*(optp + 1);
case IP6OPT_TYPE_DISCARD: /* silently discard */
m_freem(m);
return -1;
case IP6OPT_TYPE_FORCEICMP: /* send ICMP even if multicasted */
ip6stat.ip6s_badoptions++;
icmp6_error(m, ICMP6_PARAM_PROB, ICMP6_PARAMPROB_OPTION, (int)off);
return -1;
case IP6OPT_TYPE_ICMP: /* send ICMP if not multicasted */
ip6stat.ip6s_badoptions++;
ip6 = mtod(m, struct ip6_hdr *);
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) ||
(m->m_flags & (M_BCAST | M_MCAST))) {
m_freem(m);
} else {
icmp6_error(m, ICMP6_PARAM_PROB,
ICMP6_PARAMPROB_OPTION, (int)off);
}
return -1;
}
m_freem(m); /* XXX: NOTREACHED */
return -1;
}
/*
* Create the "control" list for this pcb.
* These functions will not modify mbuf chain at all.
*
* With KAME mbuf chain restriction:
* The routine will be called from upper layer handlers like tcp6_input().
* Thus the routine assumes that the caller (tcp6_input) have already
* called IP6_EXTHDR_CHECK() and all the extension headers are located in the
* very first mbuf on the mbuf chain.
*
* ip6_savecontrol_v4 will handle those options that are possible to be
* set on a v4-mapped socket.
* ip6_savecontrol will directly call ip6_savecontrol_v4 to handle those
* options and handle the v6-only ones itself.
*/
struct mbuf **
ip6_savecontrol_v4(struct inpcb *inp, struct mbuf *m, struct mbuf **mp,
int *v4only)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
if ((inp->inp_socket->so_options & SO_TIMESTAMP) != 0) {
struct timeval tv;
getmicrotime(&tv);
mp = sbcreatecontrol_mbuf((caddr_t)&tv, sizeof(tv),
SCM_TIMESTAMP, SOL_SOCKET, mp);
if (*mp == NULL) {
return NULL;
}
}
if ((inp->inp_socket->so_options & SO_TIMESTAMP_MONOTONIC) != 0) {
uint64_t time;
time = mach_absolute_time();
mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time),
SCM_TIMESTAMP_MONOTONIC, SOL_SOCKET, mp);
if (*mp == NULL) {
return NULL;
}
}
if ((inp->inp_socket->so_options & SO_TIMESTAMP_CONTINUOUS) != 0) {
uint64_t time;
time = mach_continuous_time();
mp = sbcreatecontrol_mbuf((caddr_t)&time, sizeof(time),
SCM_TIMESTAMP_CONTINUOUS, SOL_SOCKET, mp);
if (*mp == NULL) {
return NULL;
}
}
if ((inp->inp_socket->so_flags & SOF_RECV_TRAFFIC_CLASS) != 0) {
int tc = m_get_traffic_class(m);
mp = sbcreatecontrol_mbuf((caddr_t)&tc, sizeof(tc),
SO_TRAFFIC_CLASS, SOL_SOCKET, mp);
if (*mp == NULL) {
return NULL;
}
}
if ((inp->inp_socket->so_flags & SOF_RECV_WAKE_PKT) &&
(m->m_pkthdr.pkt_flags & PKTF_WAKE_PKT)) {
int flag = 1;
mp = sbcreatecontrol_mbuf((caddr_t)&flag, sizeof(flag),
SO_RECV_WAKE_PKT, SOL_SOCKET, mp);
if (*mp == NULL) {
return NULL;
}
}
#define IS2292(inp, x, y) (((inp)->inp_flags & IN6P_RFC2292) ? (x) : (y))
if ((ip6->ip6_vfc & IPV6_VERSION_MASK) != IPV6_VERSION) {
if (v4only != NULL) {
*v4only = 1;
}
// Send ECN flags for v4-mapped addresses
if ((inp->inp_flags & IN6P_TCLASS) != 0) {
struct ip *ip_header = mtod(m, struct ip *);
int tclass = (int)(ip_header->ip_tos);
mp = sbcreatecontrol_mbuf((caddr_t)&tclass, sizeof(tclass),
IPV6_TCLASS, IPPROTO_IPV6, mp);
if (*mp == NULL) {
return NULL;
}
}
// Send IN6P_PKTINFO for v4-mapped address
if ((inp->inp_flags & IN6P_PKTINFO) != 0 || SOFLOW_ENABLED(inp->inp_socket)) {
struct in6_pktinfo pi6 = {
.ipi6_addr = IN6ADDR_V4MAPPED_INIT,
.ipi6_ifindex = (m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0,
};
struct ip *ip_header = mtod(m, struct ip *);
bcopy(&ip_header->ip_dst, &pi6.ipi6_addr.s6_addr32[3], sizeof(struct in_addr));
mp = sbcreatecontrol_mbuf((caddr_t)&pi6,
sizeof(struct in6_pktinfo),
IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO),
IPPROTO_IPV6, mp);
if (*mp == NULL) {
return NULL;
}
}
return mp;
}
/* RFC 2292 sec. 5 */
if ((inp->inp_flags & IN6P_PKTINFO) != 0 || SOFLOW_ENABLED(inp->inp_socket)) {
struct in6_pktinfo pi6;
bcopy(&ip6->ip6_dst, &pi6.ipi6_addr, sizeof(struct in6_addr));
in6_clearscope(&pi6.ipi6_addr); /* XXX */
pi6.ipi6_ifindex =
(m && m->m_pkthdr.rcvif) ? m->m_pkthdr.rcvif->if_index : 0;
mp = sbcreatecontrol_mbuf((caddr_t)&pi6,
sizeof(struct in6_pktinfo),
IS2292(inp, IPV6_2292PKTINFO, IPV6_PKTINFO),
IPPROTO_IPV6, mp);
if (*mp == NULL) {
return NULL;
}
}
if ((inp->inp_flags & IN6P_HOPLIMIT) != 0) {
int hlim = ip6->ip6_hlim & 0xff;
mp = sbcreatecontrol_mbuf((caddr_t)&hlim, sizeof(int),
IS2292(inp, IPV6_2292HOPLIMIT, IPV6_HOPLIMIT),
IPPROTO_IPV6, mp);
if (*mp == NULL) {
return NULL;
}
}
if (v4only != NULL) {
*v4only = 0;
}
return mp;
}
int
ip6_savecontrol(struct inpcb *in6p, struct mbuf *m, struct mbuf **mp)
{
struct mbuf **np;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
int v4only = 0;
*mp = NULL;
np = ip6_savecontrol_v4(in6p, m, mp, &v4only);
if (np == NULL) {
goto no_mbufs;
}
mp = np;
if (v4only) {
return 0;
}
if ((in6p->inp_flags & IN6P_TCLASS) != 0) {
u_int32_t flowinfo;
int tclass;
flowinfo = (u_int32_t)ntohl(ip6->ip6_flow & IPV6_FLOWINFO_MASK);
flowinfo >>= 20;
tclass = flowinfo & 0xff;
mp = sbcreatecontrol_mbuf((caddr_t)&tclass, sizeof(tclass),
IPV6_TCLASS, IPPROTO_IPV6, mp);
if (*mp == NULL) {
goto no_mbufs;
}
}
/*
* IPV6_HOPOPTS socket option. Recall that we required super-user
* privilege for the option (see ip6_ctloutput), but it might be too
* strict, since there might be some hop-by-hop options which can be
* returned to normal user.
* See also RFC 2292 section 6 (or RFC 3542 section 8).
*/
if ((in6p->inp_flags & IN6P_HOPOPTS) != 0) {
/*
* Check if a hop-by-hop options header is contatined in the
* received packet, and if so, store the options as ancillary
* data. Note that a hop-by-hop options header must be
* just after the IPv6 header, which is assured through the
* IPv6 input processing.
*/
ip6 = mtod(m, struct ip6_hdr *);
if (ip6->ip6_nxt == IPPROTO_HOPOPTS) {
struct ip6_hbh *hbh;
int hbhlen = 0;
hbh = (struct ip6_hbh *)(ip6 + 1);
hbhlen = (hbh->ip6h_len + 1) << 3;
/*
* XXX: We copy the whole header even if a
* jumbo payload option is included, the option which
* is to be removed before returning according to
* RFC2292.
* Note: this constraint is removed in RFC3542
*/
mp = sbcreatecontrol_mbuf((caddr_t)hbh, hbhlen,
IS2292(in6p, IPV6_2292HOPOPTS, IPV6_HOPOPTS),
IPPROTO_IPV6, mp);
if (*mp == NULL) {
goto no_mbufs;
}
}
}
if ((in6p->inp_flags & (IN6P_RTHDR | IN6P_DSTOPTS)) != 0) {
int nxt = ip6->ip6_nxt, off = sizeof(struct ip6_hdr);
/*
* Search for destination options headers or routing
* header(s) through the header chain, and stores each
* header as ancillary data.
* Note that the order of the headers remains in
* the chain of ancillary data.
*/
while (1) { /* is explicit loop prevention necessary? */
struct ip6_ext *ip6e = NULL;
int elen;
/*
* if it is not an extension header, don't try to
* pull it from the chain.
*/
switch (nxt) {
case IPPROTO_DSTOPTS:
case IPPROTO_ROUTING:
case IPPROTO_HOPOPTS:
case IPPROTO_AH: /* is it possible? */
break;
default:
goto loopend;
}
if (off + sizeof(*ip6e) > m->m_len) {
goto loopend;
}
ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + off);
if (nxt == IPPROTO_AH) {
elen = (ip6e->ip6e_len + 2) << 2;
} else {
elen = (ip6e->ip6e_len + 1) << 3;
}
if (off + elen > m->m_len) {
goto loopend;
}
switch (nxt) {
case IPPROTO_DSTOPTS:
if (!(in6p->inp_flags & IN6P_DSTOPTS)) {
break;
}
mp = sbcreatecontrol_mbuf((caddr_t)ip6e, elen,
IS2292(in6p, IPV6_2292DSTOPTS,
IPV6_DSTOPTS), IPPROTO_IPV6, mp);
if (*mp == NULL) {
goto no_mbufs;
}
break;
case IPPROTO_ROUTING:
if (!(in6p->inp_flags & IN6P_RTHDR)) {
break;
}
mp = sbcreatecontrol_mbuf((caddr_t)ip6e, elen,
IS2292(in6p, IPV6_2292RTHDR, IPV6_RTHDR),
IPPROTO_IPV6, mp);
if (*mp == NULL) {
goto no_mbufs;
}
break;
case IPPROTO_HOPOPTS:
case IPPROTO_AH: /* is it possible? */
break;
default:
/*
* other cases have been filtered in the above.
* none will visit this case. here we supply
* the code just in case (nxt overwritten or
* other cases).
*/
goto loopend;
}
/* proceed with the next header. */
off += elen;
nxt = ip6e->ip6e_nxt;
ip6e = NULL;
}
loopend:
;
}
return 0;
no_mbufs:
ip6stat.ip6s_pktdropcntrl++;
/* XXX increment a stat to show the failure */
return ENOBUFS;
}
#undef IS2292
void
ip6_notify_pmtu(struct inpcb *in6p, struct sockaddr_in6 *dst, u_int32_t *mtu)
{
struct socket *so;
struct mbuf *m_mtu;
struct ip6_mtuinfo mtuctl;
so = in6p->inp_socket;
if ((in6p->inp_flags & IN6P_MTU) == 0) {
return;
}
if (mtu == NULL) {
return;
}
if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) && SOCK_CHECK_PROTO(so, IPPROTO_TCP)) {
return;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
!in6_are_addr_equal_scoped(&in6p->in6p_faddr, &dst->sin6_addr, in6p->inp_fifscope, dst->sin6_scope_id)) {
return;
}
bzero(&mtuctl, sizeof(mtuctl)); /* zero-clear for safety */
mtuctl.ip6m_mtu = *mtu;
mtuctl.ip6m_addr = *dst;
if (!in6_embedded_scope) {
mtuctl.ip6m_addr.sin6_scope_id = dst->sin6_scope_id;
}
if (sa6_recoverscope(&mtuctl.ip6m_addr, TRUE)) {
return;
}
if ((m_mtu = sbcreatecontrol((caddr_t)&mtuctl, sizeof(mtuctl),
IPV6_PATHMTU, IPPROTO_IPV6)) == NULL) {
return;
}
if (sbappendaddr(&so->so_rcv, SA(dst), NULL, m_mtu, NULL) == 0) {
return;
}
sorwakeup(so);
}
/*
* Get pointer to the previous header followed by the header
* currently processed.
* XXX: This function supposes that
* M includes all headers,
* the next header field and the header length field of each header
* are valid, and
* the sum of each header length equals to OFF.
* Because of these assumptions, this function must be called very
* carefully. Moreover, it will not be used in the near future when
* we develop `neater' mechanism to process extension headers.
*/
char *
ip6_get_prevhdr(struct mbuf *m, int off)
{
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
if (off == sizeof(struct ip6_hdr)) {
return (char *)&ip6->ip6_nxt;
} else {
int len, nxt;
struct ip6_ext *ip6e = NULL;
nxt = ip6->ip6_nxt;
len = sizeof(struct ip6_hdr);
while (len < off) {
ip6e = (struct ip6_ext *)(mtod(m, caddr_t) + len);
switch (nxt) {
case IPPROTO_FRAGMENT:
len += sizeof(struct ip6_frag);
break;
case IPPROTO_AH:
len += (ip6e->ip6e_len + 2) << 2;
break;
default:
len += (ip6e->ip6e_len + 1) << 3;
break;
}
nxt = ip6e->ip6e_nxt;
}
if (ip6e) {
return (char *)&ip6e->ip6e_nxt;
} else {
return NULL;
}
}
}
/*
* get next header offset. m will be retained.
*/
int
ip6_nexthdr(struct mbuf *m, int off, int proto, int *nxtp)
{
struct ip6_hdr ip6;
struct ip6_ext ip6e;
struct ip6_frag fh;
/* just in case */
VERIFY(m != NULL);
if ((m->m_flags & M_PKTHDR) == 0 || m->m_pkthdr.len < off) {
return -1;
}
switch (proto) {
case IPPROTO_IPV6:
if (m->m_pkthdr.len < off + sizeof(ip6)) {
return -1;
}
m_copydata(m, off, sizeof(ip6), (caddr_t)&ip6);
if (nxtp) {
*nxtp = ip6.ip6_nxt;
}
off += sizeof(ip6);
return off;
case IPPROTO_FRAGMENT:
/*
* terminate parsing if it is not the first fragment,
* it does not make sense to parse through it.
*/
if (m->m_pkthdr.len < off + sizeof(fh)) {
return -1;
}
m_copydata(m, off, sizeof(fh), (caddr_t)&fh);
/* IP6F_OFF_MASK = 0xfff8(BigEndian), 0xf8ff(LittleEndian) */
if (fh.ip6f_offlg & IP6F_OFF_MASK) {
return -1;
}
if (nxtp) {
*nxtp = fh.ip6f_nxt;
}
off += sizeof(struct ip6_frag);
return off;
case IPPROTO_AH:
if (m->m_pkthdr.len < off + sizeof(ip6e)) {
return -1;
}
m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
if (nxtp) {
*nxtp = ip6e.ip6e_nxt;
}
off += (ip6e.ip6e_len + 2) << 2;
return off;
case IPPROTO_HOPOPTS:
case IPPROTO_ROUTING:
case IPPROTO_DSTOPTS:
if (m->m_pkthdr.len < off + sizeof(ip6e)) {
return -1;
}
m_copydata(m, off, sizeof(ip6e), (caddr_t)&ip6e);
if (nxtp) {
*nxtp = ip6e.ip6e_nxt;
}
off += (ip6e.ip6e_len + 1) << 3;
return off;
case IPPROTO_NONE:
case IPPROTO_ESP:
case IPPROTO_IPCOMP:
/* give up */
return -1;
default:
return -1;
}
}
/*
* get offset for the last header in the chain. m will be kept untainted.
*/
int
ip6_lasthdr(struct mbuf *m, int off, int proto, int *nxtp)
{
int newoff;
int nxt;
if (!nxtp) {
nxt = -1;
nxtp = &nxt;
}
while (1) {
newoff = ip6_nexthdr(m, off, proto, nxtp);
if (newoff < 0) {
return off;
} else if (newoff < off) {
return -1; /* invalid */
} else if (newoff == off) {
return newoff;
}
off = newoff;
proto = *nxtp;
}
}
boolean_t
ip6_pkt_has_ulp(struct mbuf *m)
{
int off = 0, nxt = IPPROTO_NONE;
off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
if (off < 0 || m->m_pkthdr.len < off) {
return FALSE;
}
switch (nxt) {
case IPPROTO_TCP:
if (off + sizeof(struct tcphdr) > m->m_pkthdr.len) {
return FALSE;
}
break;
case IPPROTO_UDP:
if (off + sizeof(struct udphdr) > m->m_pkthdr.len) {
return FALSE;
}
break;
case IPPROTO_ICMPV6:
if (off + sizeof(uint32_t) > m->m_pkthdr.len) {
return FALSE;
}
break;
case IPPROTO_NONE:
return TRUE;
case IPPROTO_ESP:
return TRUE;
case IPPROTO_IPCOMP:
return TRUE;
default:
return FALSE;
}
return TRUE;
}
struct ip6aux *
ip6_addaux(struct mbuf *m)
{
struct m_tag *tag;
/* Check if one is already allocated */
tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
KERNEL_TAG_TYPE_INET6);
if (tag == NULL) {
/* Allocate a tag */
tag = m_tag_create(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_INET6,
sizeof(struct ip6aux), M_DONTWAIT, m);
/* Attach it to the mbuf */
if (tag) {
m_tag_prepend(m, tag);
}
}
return tag ? (struct ip6aux *)(tag->m_tag_data) : NULL;
}
struct ip6aux *
ip6_findaux(struct mbuf *m)
{
struct m_tag *tag;
tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
KERNEL_TAG_TYPE_INET6);
return tag != NULL ? (struct ip6aux *)(tag->m_tag_data) : NULL;
}
void
ip6_delaux(struct mbuf *m)
{
struct m_tag *tag;
tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID,
KERNEL_TAG_TYPE_INET6);
if (tag != NULL) {
m_tag_delete(m, tag);
}
}
struct inet6_tag_container {
struct m_tag inet6_m_tag;
struct ip6aux inet6_ip6a;
};
struct m_tag *
m_tag_kalloc_inet6(u_int32_t id, u_int16_t type, uint16_t len, int wait)
{
struct inet6_tag_container *tag_container;
struct m_tag *tag = NULL;
assert3u(id, ==, KERNEL_MODULE_TAG_ID);
assert3u(type, ==, KERNEL_TAG_TYPE_INET6);
assert3u(len, ==, sizeof(struct ip6aux));
if (len != sizeof(struct ip6aux)) {
return NULL;
}
tag_container = kalloc_type(struct inet6_tag_container, wait | M_ZERO);
if (tag_container != NULL) {
tag = &tag_container->inet6_m_tag;
assert3p(tag, ==, tag_container);
M_TAG_INIT(tag, id, type, len, &tag_container->inet6_ip6a, NULL);
}
return tag;
}
void
m_tag_kfree_inet6(struct m_tag *tag)
{
struct inet6_tag_container *tag_container = (struct inet6_tag_container *)tag;
assert3u(tag->m_tag_len, ==, sizeof(struct ip6aux));
kfree_type(struct inet6_tag_container, tag_container);
}
void
ip6_register_m_tag(void)
{
int error;
error = m_register_internal_tag_type(KERNEL_TAG_TYPE_INET6, sizeof(struct ip6aux),
m_tag_kalloc_inet6, m_tag_kfree_inet6);
assert3u(error, ==, 0);
}
/*
* Drain callback
*/
void
ip6_drain(void)
{
frag6_drain(); /* fragments */
in6_rtqdrain(); /* protocol cloned routes */
nd6_drain(NULL); /* cloned routes: ND6 */
}
/*
* System control for IP6
*/
u_char inet6ctlerrmap[PRC_NCMDS] = {
0, 0, 0, 0,
0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH,
EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED,
EMSGSIZE, EHOSTUNREACH, 0, 0,
0, 0, 0, 0,
ENOPROTOOPT, ECONNREFUSED
};
static int
sysctl_reset_ip6_input_stats SYSCTL_HANDLER_ARGS
{
#pragma unused(arg1, arg2)
int error, i;
i = ip6_input_measure;
error = sysctl_handle_int(oidp, &i, 0, req);
if (error || req->newptr == USER_ADDR_NULL) {
goto done;
}
/* impose bounds */
if (i < 0 || i > 1) {
error = EINVAL;
goto done;
}
if (ip6_input_measure != i && i == 1) {
net_perf_initialize(&net_perf, ip6_input_measure_bins);
}
ip6_input_measure = i;
done:
return error;
}
static int
sysctl_ip6_input_measure_bins SYSCTL_HANDLER_ARGS
{
#pragma unused(arg1, arg2)
int error;
uint64_t i;
i = ip6_input_measure_bins;
error = sysctl_handle_quad(oidp, &i, 0, req);
if (error || req->newptr == USER_ADDR_NULL) {
goto done;
}
/* validate data */
if (!net_perf_validate_bins(i)) {
error = EINVAL;
goto done;
}
ip6_input_measure_bins = i;
done:
return error;
}
static int
sysctl_ip6_input_getperf SYSCTL_HANDLER_ARGS
{
#pragma unused(oidp, arg1, arg2)
if (req->oldptr == USER_ADDR_NULL) {
req->oldlen = (size_t)sizeof(struct net_perf);
}
return SYSCTL_OUT(req, &net_perf, MIN(sizeof(net_perf), req->oldlen));
}
/*
* Initialize IPv6 source address hash table.
*/
static void
in6_ifaddrhashtbl_init(void)
{
int i, k, p;
if (in6_ifaddrhashtbl != NULL) {
return;
}
PE_parse_boot_argn("ina6ddr_nhash", &in6addr_nhash,
sizeof(in6addr_nhash));
if (in6addr_nhash == 0) {
in6addr_nhash = IN6ADDR_NHASH;
}
in6_ifaddrhashtbl = zalloc_permanent(
in6addr_nhash * sizeof(*in6_ifaddrhashtbl),
ZALIGN_PTR);
/*
* Generate the next largest prime greater than in6addr_nhash.
*/
k = (in6addr_nhash % 2 == 0) ? in6addr_nhash + 1 : in6addr_nhash + 2;
for (;;) {
p = 1;
for (i = 3; i * i <= k; i += 2) {
if (k % i == 0) {
p = 0;
}
}
if (p == 1) {
break;
}
k += 2;
}
in6addr_hashp = k;
}
static int
sysctl_ip6_checkinterface SYSCTL_HANDLER_ARGS
{
#pragma unused(arg1, arg2)
int error, i;
i = ip6_checkinterface;
error = sysctl_handle_int(oidp, &i, 0, req);
if (error || req->newptr == USER_ADDR_NULL) {
return error;
}
switch (i) {
case IP6_CHECKINTERFACE_WEAK_ES:
case IP6_CHECKINTERFACE_HYBRID_ES:
case IP6_CHECKINTERFACE_STRONG_ES:
if (ip6_checkinterface != i) {
ip6_checkinterface = i;
os_log(OS_LOG_DEFAULT, "%s: ip6_checkinterface is now %d\n",
__func__, ip6_checkinterface);
}
break;
default:
error = EINVAL;
break;
}
return error;
}