This is xnu-11215.1.10. See this file in:
/*
* Copyright (c) 2004-2024 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@
*/
#include <sys/param.h> /* for definition of NULL */
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/mbuf.h>
#include <sys/systm.h>
#include <libkern/OSAtomic.h>
#include <machine/endian.h>
#define _IP_VHL
#include <net/if_var.h>
#include <net/route.h>
#include <net/kpi_protocol.h>
#include <net/net_api_stats.h>
#if SKYWALK
#include <skywalk/lib//net_filter_event.h>
#endif /* SKYWALK */
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet6/in6_var.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/ip_var.h>
#include <netinet6/ip6_var.h>
#include <netinet/kpi_ipfilter_var.h>
#include <stdbool.h>
#if SKYWALK
#include <skywalk/core/skywalk_var.h>
#endif /* SKYWALK */
/*
* kipf_lock and kipf_ref protect the linkage of the list of IP filters
* An IP filter can be removed only when kipf_ref is zero
* If an IP filter cannot be removed because kipf_ref is not null, then
* the IP filter is marjed and kipf_delayed_remove is set so that when
* kipf_ref eventually goes down to zero, the IP filter is removed
*/
static LCK_GRP_DECLARE(kipf_lock_grp, "IP Filter");
static LCK_MTX_DECLARE(kipf_lock, &kipf_lock_grp);
static u_int32_t kipf_ref = 0;
static u_int32_t kipf_delayed_remove = 0;
u_int32_t kipf_count = 0;
__private_extern__ struct ipfilter_list ipv4_filters = TAILQ_HEAD_INITIALIZER(ipv4_filters);
__private_extern__ struct ipfilter_list ipv6_filters = TAILQ_HEAD_INITIALIZER(ipv6_filters);
__private_extern__ struct ipfilter_list tbr_filters = TAILQ_HEAD_INITIALIZER(tbr_filters);
#undef ipf_addv4
#undef ipf_addv6
extern errno_t ipf_addv4(const struct ipf_filter *filter,
ipfilter_t *filter_ref);
extern errno_t ipf_addv6(const struct ipf_filter *filter,
ipfilter_t *filter_ref);
static errno_t ipf_add(const struct ipf_filter *filter,
ipfilter_t *filter_ref, struct ipfilter_list *head, bool is_internal);
#if SKYWALK
static bool net_check_compatible_ipf(void);
#endif /* SKYWALK */
__private_extern__ void
ipf_ref(void)
{
lck_mtx_lock(&kipf_lock);
if (os_inc_overflow(&kipf_ref)) {
panic("kipf_ref overflow");
}
lck_mtx_unlock(&kipf_lock);
}
__private_extern__ void
ipf_unref(void)
{
lck_mtx_lock(&kipf_lock);
if (os_dec_overflow(&kipf_ref)) {
panic("kipf_ref underflow");
}
if (kipf_ref == 0 && kipf_delayed_remove != 0) {
struct ipfilter *filter;
while ((filter = TAILQ_FIRST(&tbr_filters))) {
VERIFY(OSDecrementAtomic64(&net_api_stats.nas_ipf_add_count) > 0);
if (filter->ipf_flags & IPFF_INTERNAL) {
VERIFY(OSDecrementAtomic64(&net_api_stats.nas_ipf_add_os_count) > 0);
}
ipf_detach_func ipf_detach = filter->ipf_filter.ipf_detach;
void *__single cookie = filter->ipf_filter.cookie;
TAILQ_REMOVE(filter->ipf_head, filter, ipf_link);
TAILQ_REMOVE(&tbr_filters, filter, ipf_tbr);
kipf_delayed_remove--;
if (ipf_detach) {
lck_mtx_unlock(&kipf_lock);
ipf_detach(cookie);
lck_mtx_lock(&kipf_lock);
/* In case some filter got to run while we released the lock */
if (kipf_ref != 0) {
break;
}
}
}
}
#if SKYWALK
if (kernel_is_macos_or_server()) {
net_filter_event_mark(NET_FILTER_EVENT_IP,
net_check_compatible_ipf());
}
#endif /* SKYWALK */
lck_mtx_unlock(&kipf_lock);
}
static errno_t
ipf_add(
const struct ipf_filter *filter,
ipfilter_t *filter_ref,
struct ipfilter_list *head,
bool is_internal)
{
struct ipfilter *new_filter;
if (filter->name == NULL || (filter->ipf_input == NULL && filter->ipf_output == NULL)) {
return EINVAL;
}
new_filter = kalloc_type(struct ipfilter, Z_WAITOK | Z_NOFAIL);
lck_mtx_lock(&kipf_lock);
new_filter->ipf_filter = *filter;
new_filter->ipf_head = head;
TAILQ_INSERT_HEAD(head, new_filter, ipf_link);
OSIncrementAtomic64(&net_api_stats.nas_ipf_add_count);
INC_ATOMIC_INT64_LIM(net_api_stats.nas_ipf_add_total);
if (is_internal) {
new_filter->ipf_flags = IPFF_INTERNAL;
OSIncrementAtomic64(&net_api_stats.nas_ipf_add_os_count);
INC_ATOMIC_INT64_LIM(net_api_stats.nas_ipf_add_os_total);
}
#if SKYWALK
if (kernel_is_macos_or_server()) {
net_filter_event_mark(NET_FILTER_EVENT_IP,
net_check_compatible_ipf());
}
#endif /* SKYWALK */
lck_mtx_unlock(&kipf_lock);
*filter_ref = (ipfilter_t)new_filter;
/* This will force TCP to re-evaluate its use of TSO */
OSAddAtomic(1, &kipf_count);
routegenid_update();
return 0;
}
errno_t
ipf_addv4_internal(
const struct ipf_filter *filter,
ipfilter_t *filter_ref)
{
return ipf_add(filter, filter_ref, &ipv4_filters, true);
}
errno_t
ipf_addv4(
const struct ipf_filter *filter,
ipfilter_t *filter_ref)
{
return ipf_add(filter, filter_ref, &ipv4_filters, false);
}
errno_t
ipf_addv6_internal(
const struct ipf_filter *filter,
ipfilter_t *filter_ref)
{
return ipf_add(filter, filter_ref, &ipv6_filters, true);
}
errno_t
ipf_addv6(
const struct ipf_filter *filter,
ipfilter_t *filter_ref)
{
return ipf_add(filter, filter_ref, &ipv6_filters, false);
}
static errno_t
ipf_input_detached(void *cookie, mbuf_t *data, int offset, u_int8_t protocol)
{
#pragma unused(cookie, data, offset, protocol)
#if DEBUG
printf("ipf_input_detached\n");
#endif /* DEBUG */
return 0;
}
static errno_t
ipf_output_detached(void *cookie, mbuf_t *data, ipf_pktopts_t options)
{
#pragma unused(cookie, data, options)
#if DEBUG
printf("ipf_output_detached\n");
#endif /* DEBUG */
return 0;
}
errno_t
ipf_remove(
ipfilter_t filter_ref)
{
struct ipfilter *match = (struct ipfilter *)filter_ref;
struct ipfilter_list *head;
if (match == 0 || (match->ipf_head != &ipv4_filters && match->ipf_head != &ipv6_filters)) {
return EINVAL;
}
head = match->ipf_head;
lck_mtx_lock(&kipf_lock);
TAILQ_FOREACH(match, head, ipf_link) {
if (match == (struct ipfilter *)filter_ref) {
ipf_detach_func ipf_detach = match->ipf_filter.ipf_detach;
void *__single cookie = match->ipf_filter.cookie;
/*
* Cannot detach when they are filters running
*/
if (kipf_ref) {
kipf_delayed_remove++;
TAILQ_INSERT_TAIL(&tbr_filters, match, ipf_tbr);
match->ipf_filter.ipf_input = ipf_input_detached;
match->ipf_filter.ipf_output = ipf_output_detached;
lck_mtx_unlock(&kipf_lock);
} else {
VERIFY(OSDecrementAtomic64(&net_api_stats.nas_ipf_add_count) > 0);
if (match->ipf_flags & IPFF_INTERNAL) {
VERIFY(OSDecrementAtomic64(&net_api_stats.nas_ipf_add_os_count) > 0);
}
TAILQ_REMOVE(head, match, ipf_link);
lck_mtx_unlock(&kipf_lock);
if (ipf_detach) {
ipf_detach(cookie);
}
kfree_type(struct ipfilter, match);
/* This will force TCP to re-evaluate its use of TSO */
OSAddAtomic(-1, &kipf_count);
routegenid_update();
}
return 0;
}
}
#if SKYWALK
if (kernel_is_macos_or_server()) {
net_filter_event_mark(NET_FILTER_EVENT_IP,
net_check_compatible_ipf());
}
#endif /* SKYWALK */
lck_mtx_unlock(&kipf_lock);
return ENOENT;
}
int log_for_en1 = 0;
errno_t
ipf_inject_input(
mbuf_t data,
ipfilter_t filter_ref)
{
struct mbuf *m = (struct mbuf *)data;
struct m_tag *mtag = 0;
struct ip *ip = mtod(m, struct ip *);
struct ip6_hdr *ip6;
u_int8_t vers;
int hlen;
errno_t error = 0;
protocol_family_t proto;
struct in_ifaddr *ia = NULL;
struct in_addr *pkt_dst = NULL;
struct in6_ifaddr *ia6 = NULL;
struct sockaddr_in6 pkt_dst6;
vers = IP_VHL_V(ip->ip_vhl);
switch (vers) {
case 4:
proto = PF_INET;
break;
case 6:
proto = PF_INET6;
break;
default:
error = ENOTSUP;
goto done;
}
if (filter_ref == 0 && m->m_pkthdr.rcvif == 0) {
/*
* Search for interface with the local address
*/
switch (proto) {
case PF_INET:
pkt_dst = &ip->ip_dst;
lck_rw_lock_shared(&in_ifaddr_rwlock);
TAILQ_FOREACH(ia, INADDR_HASH(pkt_dst->s_addr), ia_hash) {
if (IA_SIN(ia)->sin_addr.s_addr == pkt_dst->s_addr) {
m->m_pkthdr.rcvif = ia->ia_ifp;
break;
}
}
lck_rw_done(&in_ifaddr_rwlock);
break;
case PF_INET6:
ip6 = mtod(m, struct ip6_hdr *);
pkt_dst6.sin6_addr = ip6->ip6_dst;
lck_rw_lock_shared(&in6_ifaddr_rwlock);
TAILQ_FOREACH(ia6, IN6ADDR_HASH(&pkt_dst6.sin6_addr), ia6_hash) {
if (IN6_ARE_ADDR_EQUAL(&ia6->ia_addr.sin6_addr, &pkt_dst6.sin6_addr)) {
m->m_pkthdr.rcvif = ia6->ia_ifp;
break;
}
}
lck_rw_done(&in6_ifaddr_rwlock);
break;
default:
break;
}
/*
* If none found, fallback to loopback
*/
if (m->m_pkthdr.rcvif == NULL) {
m->m_pkthdr.rcvif = lo_ifp;
}
m->m_pkthdr.csum_data = 0;
m->m_pkthdr.csum_flags = 0;
if (vers == 4) {
hlen = IP_VHL_HL(ip->ip_vhl) << 2;
ip->ip_sum = 0;
ip->ip_sum = in_cksum(m, hlen);
}
}
if (filter_ref != 0) {
mtag = m_tag_create(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
sizeof(ipfilter_t), M_NOWAIT, m);
if (mtag == NULL) {
error = ENOMEM;
goto done;
}
*(ipfilter_t *)(mtag->m_tag_data) = filter_ref;
m_tag_prepend(m, mtag);
}
error = proto_inject(proto, data);
done:
return error;
}
static errno_t
ipf_injectv4_out(mbuf_t data, ipfilter_t filter_ref, ipf_pktopts_t options)
{
struct route ro;
struct ip *ip;
struct mbuf *m = (struct mbuf *)data;
errno_t error = 0;
struct m_tag *mtag = NULL;
struct ip_moptions *imo = NULL;
struct ip_out_args ipoa;
bzero(&ipoa, sizeof(ipoa));
ipoa.ipoa_boundif = IFSCOPE_NONE;
ipoa.ipoa_sotc = SO_TC_UNSPEC;
ipoa.ipoa_netsvctype = _NET_SERVICE_TYPE_UNSPEC;
/* Make the IP header contiguous in the mbuf */
if ((size_t)m->m_len < sizeof(struct ip)) {
m = m_pullup(m, sizeof(struct ip));
if (m == NULL) {
return ENOMEM;
}
}
ip = mtod(m, struct ip *);
if (filter_ref != 0) {
mtag = m_tag_create(KERNEL_MODULE_TAG_ID,
KERNEL_TAG_TYPE_IPFILT, sizeof(ipfilter_t), M_NOWAIT, m);
if (mtag == NULL) {
m_freem(m);
return ENOMEM;
}
*(ipfilter_t *)(mtag->m_tag_data) = filter_ref;
m_tag_prepend(m, mtag);
}
if (options != NULL && (options->ippo_flags & IPPOF_MCAST_OPTS) &&
(imo = ip_allocmoptions(Z_NOWAIT)) != NULL) {
imo->imo_multicast_ifp = options->ippo_mcast_ifnet;
imo->imo_multicast_ttl = options->ippo_mcast_ttl;
imo->imo_multicast_loop = (u_char)options->ippo_mcast_loop;
}
if (options != NULL) {
if (options->ippo_flags & IPPOF_SELECT_SRCIF) {
ipoa.ipoa_flags |= IPOAF_SELECT_SRCIF;
}
if (options->ippo_flags & IPPOF_BOUND_IF) {
ipoa.ipoa_flags |= IPOAF_BOUND_IF;
ipoa.ipoa_boundif = options->ippo_flags >>
IPPOF_SHIFT_IFSCOPE;
}
if (options->ippo_flags & IPPOF_NO_IFT_CELLULAR) {
ipoa.ipoa_flags |= IPOAF_NO_CELLULAR;
}
if (options->ippo_flags & IPPOF_BOUND_SRCADDR) {
ipoa.ipoa_flags |= IPOAF_BOUND_SRCADDR;
}
if (options->ippo_flags & IPPOF_NO_IFF_EXPENSIVE) {
ipoa.ipoa_flags |= IPOAF_NO_EXPENSIVE;
}
if (options->ippo_flags & IPPOF_NO_IFF_CONSTRAINED) {
ipoa.ipoa_flags |= IPOAF_NO_CONSTRAINED;
}
}
bzero(&ro, sizeof(struct route));
/* Put ip_len and ip_off in host byte order, ip_output expects that */
#if BYTE_ORDER != BIG_ENDIAN
NTOHS(ip->ip_len);
NTOHS(ip->ip_off);
#endif
/* Send; enforce source interface selection via IP_OUTARGS flag */
error = ip_output(m, NULL, &ro,
IP_ALLOWBROADCAST | IP_RAWOUTPUT | IP_OUTARGS, imo, &ipoa);
/* Release the route */
ROUTE_RELEASE(&ro);
if (imo != NULL) {
IMO_REMREF(imo);
}
return error;
}
static errno_t
ipf_injectv6_out(mbuf_t data, ipfilter_t filter_ref, ipf_pktopts_t options)
{
struct route_in6 ro;
struct ip6_hdr *ip6;
struct mbuf *m = (struct mbuf *)data;
errno_t error = 0;
struct m_tag *mtag = NULL;
struct ip6_moptions *im6o = NULL;
struct ip6_out_args ip6oa;
bzero(&ip6oa, sizeof(ip6oa));
ip6oa.ip6oa_boundif = IFSCOPE_NONE;
ip6oa.ip6oa_sotc = SO_TC_UNSPEC;
ip6oa.ip6oa_netsvctype = _NET_SERVICE_TYPE_UNSPEC;
/* Make the IP header contiguous in the mbuf */
if ((size_t)m->m_len < sizeof(struct ip6_hdr)) {
m = m_pullup(m, sizeof(struct ip6_hdr));
if (m == NULL) {
return ENOMEM;
}
}
ip6 = mtod(m, struct ip6_hdr *);
if (filter_ref != 0) {
mtag = m_tag_create(KERNEL_MODULE_TAG_ID,
KERNEL_TAG_TYPE_IPFILT, sizeof(ipfilter_t), M_NOWAIT, m);
if (mtag == NULL) {
m_freem(m);
return ENOMEM;
}
*(ipfilter_t *)(mtag->m_tag_data) = filter_ref;
m_tag_prepend(m, mtag);
}
if (options != NULL && (options->ippo_flags & IPPOF_MCAST_OPTS) &&
(im6o = ip6_allocmoptions(Z_NOWAIT)) != NULL) {
im6o->im6o_multicast_ifp = options->ippo_mcast_ifnet;
im6o->im6o_multicast_hlim = options->ippo_mcast_ttl;
im6o->im6o_multicast_loop = (u_char)options->ippo_mcast_loop;
}
if (options != NULL) {
if (options->ippo_flags & IPPOF_SELECT_SRCIF) {
ip6oa.ip6oa_flags |= IP6OAF_SELECT_SRCIF;
}
if (options->ippo_flags & IPPOF_BOUND_IF) {
ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF;
ip6oa.ip6oa_boundif = options->ippo_flags >>
IPPOF_SHIFT_IFSCOPE;
}
if (options->ippo_flags & IPPOF_NO_IFT_CELLULAR) {
ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR;
}
if (options->ippo_flags & IPPOF_BOUND_SRCADDR) {
ip6oa.ip6oa_flags |= IP6OAF_BOUND_SRCADDR;
}
if (options->ippo_flags & IPPOF_NO_IFF_EXPENSIVE) {
ip6oa.ip6oa_flags |= IP6OAF_NO_EXPENSIVE;
}
if (options->ippo_flags & IPPOF_NO_IFF_CONSTRAINED) {
ip6oa.ip6oa_flags |= IP6OAF_NO_CONSTRAINED;
}
}
bzero(&ro, sizeof(struct route_in6));
/*
* Send mbuf and ifscope information. Check for correctness
* of ifscope information is done while searching for a route in
* ip6_output.
*/
ip6_output_setsrcifscope(m, IFSCOPE_UNKNOWN, NULL);
ip6_output_setdstifscope(m, IFSCOPE_UNKNOWN, NULL);
error = ip6_output(m, NULL, &ro, IPV6_OUTARGS, im6o, NULL, &ip6oa);
/* Release the route */
ROUTE_RELEASE(&ro);
if (im6o != NULL) {
IM6O_REMREF(im6o);
}
return error;
}
errno_t
ipf_inject_output(
mbuf_t data,
ipfilter_t filter_ref,
ipf_pktopts_t options)
{
struct mbuf *m = (struct mbuf *)data;
u_int8_t vers;
errno_t error = 0;
#if SKYWALK
sk_protect_t protect = sk_async_transmit_protect();
#endif /* SKYWALK */
/* Make one byte of the header contiguous in the mbuf */
if (m->m_len < 1) {
m = m_pullup(m, 1);
if (m == NULL) {
goto done;
}
}
vers = (*(u_int8_t *)m_mtod(m)) >> 4;
switch (vers) {
case 4:
error = ipf_injectv4_out(data, filter_ref, options);
break;
case 6:
error = ipf_injectv6_out(data, filter_ref, options);
break;
default:
m_freem(m);
error = ENOTSUP;
break;
}
done:
#if SKYWALK
sk_async_transmit_unprotect(protect);
#endif /* SKYWALK */
return error;
}
__private_extern__ ipfilter_t
ipf_get_inject_filter(struct mbuf *m)
{
ipfilter_t __single filter_ref = 0;
struct m_tag *mtag;
mtag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT);
if (mtag) {
filter_ref = *(ipfilter_t *)(mtag->m_tag_data);
m_tag_delete(m, mtag);
}
return filter_ref;
}
struct ipfilt_tag_container {
struct m_tag ipft_m_tag;
ipfilter_t ipft_filter_ref;
};
static struct m_tag *
m_tag_kalloc_ipfilt(u_int32_t id, u_int16_t type, uint16_t len, int wait)
{
struct ipfilt_tag_container *tag_container;
struct m_tag *tag = NULL;
assert3u(id, ==, KERNEL_MODULE_TAG_ID);
assert3u(type, ==, KERNEL_TAG_TYPE_IPFILT);
assert3u(len, ==, sizeof(ipfilter_t));
if (len != sizeof(ipfilter_t)) {
return NULL;
}
tag_container = kalloc_type(struct ipfilt_tag_container, wait | M_ZERO);
if (tag_container != NULL) {
tag = &tag_container->ipft_m_tag;
assert3p(tag, ==, tag_container);
M_TAG_INIT(tag, id, type, len, &tag_container->ipft_filter_ref, NULL);
}
return tag;
}
static void
m_tag_kfree_ipfilt(struct m_tag *tag)
{
struct ipfilt_tag_container *tag_container = (struct ipfilt_tag_container *)tag;
assert3u(tag->m_tag_len, ==, sizeof(ipfilter_t));
kfree_type(struct ipfilt_tag_container, tag_container);
}
void
ipfilter_register_m_tag(void)
{
int error;
error = m_register_internal_tag_type(KERNEL_TAG_TYPE_IPFILT, sizeof(ipfilter_t),
m_tag_kalloc_ipfilt, m_tag_kfree_ipfilt);
assert3u(error, ==, 0);
}
#if SKYWALK
bool
net_check_compatible_ipf(void)
{
if (net_api_stats.nas_ipf_add_count > net_api_stats.nas_ipf_add_os_count) {
return false;
}
return true;
}
#endif /* SKYWALK */