[apple/xnu.git] / bsd / netinet / kpi_ipfilter.c

/*
 * Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
 * 
 * @APPLE_LICENSE_OSREFERENCE_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_LICENSE_OSREFERENCE_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>

#define _IP_VHL
#include <net/if_var.h>
#include <net/route.h>
#include <net/kpi_protocol.h>

#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>

/*
 * 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_mtx_t *kipf_lock = 0;
static unsigned long kipf_ref = 0;
static unsigned long kipf_delayed_remove = 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);

__private_extern__ void
ipf_ref(void)
{
	lck_mtx_lock(kipf_lock);
    kipf_ref++;
	lck_mtx_unlock(kipf_lock);
}

__private_extern__ void
ipf_unref(void)
{
	lck_mtx_lock(kipf_lock);

    if (kipf_ref == 0)
    	panic("ipf_unref: kipf_ref == 0\n");
    	
    kipf_ref--;
    if (kipf_ref == 0 && kipf_delayed_remove != 0) {
    	struct ipfilter *filter;

		while ((filter = TAILQ_FIRST(&tbr_filters))) {
			ipf_detach_func ipf_detach = filter->ipf_filter.ipf_detach;
			void* 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;
			}			
		}
   	} 
	lck_mtx_unlock(kipf_lock);
}

static errno_t
ipf_add(
	const struct ipf_filter* filter,
	ipfilter_t *filter_ref,
	struct ipfilter_list *head)
{
	struct ipfilter	*new_filter;
	if (filter->name == NULL || (filter->ipf_input == NULL && filter->ipf_output == NULL))
		return EINVAL;
	
	MALLOC(new_filter, struct ipfilter*, sizeof(*new_filter), M_IFADDR, M_WAITOK);
	if (new_filter == NULL)
		return ENOMEM;
	
	lck_mtx_lock(kipf_lock);
	new_filter->ipf_filter = *filter;
	new_filter->ipf_head = head;
	
	/*
	 * 3957298
	 * Make sure third parties have a chance to filter packets before
	 * SharedIP. Always SharedIP at the end of the list.
	 */
	if (filter->name != NULL &&
		strcmp(filter->name, "com.apple.nke.SharedIP") == 0) {
		TAILQ_INSERT_TAIL(head, new_filter, ipf_link);
	}
	else {
		TAILQ_INSERT_HEAD(head, new_filter, ipf_link);
	}
	
	lck_mtx_unlock(kipf_lock);
	
	*filter_ref = (ipfilter_t)new_filter;
	return 0;
}

errno_t
ipf_addv4(
	const struct ipf_filter* filter,
	ipfilter_t *filter_ref)
{
	return ipf_add(filter, filter_ref, &ipv4_filters);
}

errno_t
ipf_addv6(
	const struct ipf_filter* filter,
	ipfilter_t *filter_ref)
{
	return ipf_add(filter, filter_ref, &ipv6_filters);
}

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* 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 = 0;
				match->ipf_filter.ipf_output = 0;
				lck_mtx_unlock(kipf_lock);
			} else {
				TAILQ_REMOVE(head, match, ipf_link);
				lck_mtx_unlock(kipf_lock);
				if (ipf_detach)
					ipf_detach(cookie);
				FREE(match, M_IFADDR);
			}
			return 0;
		}
	}
	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 *);
	u_int8_t	vers;
	int hlen;
	errno_t error = 0;
	protocol_family_t proto;

	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) {
		m->m_pkthdr.rcvif = ifunit("lo0");
		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_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
					 	   sizeof (ipfilter_t), M_NOWAIT);
		if (mtag == NULL) {
			error = ENOMEM;
			goto done;
		}	
		*(ipfilter_t*)(mtag+1) = 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 sockaddr_in	*sin = (struct sockaddr_in*)&ro.ro_dst;
	struct ip	*ip;
	struct mbuf	*m = (struct mbuf*)data;
	errno_t error = 0;
	struct m_tag *mtag = 0;
	struct ip_moptions *imo = 0, ip_moptions;
	
	/* 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 = (struct ip*)m_mtod(m);
	
	if (filter_ref != 0) {
		mtag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
					 	   sizeof (ipfilter_t), M_NOWAIT);
		if (mtag == NULL) {
			m_freem(m);
			return ENOMEM;
		}
		*(ipfilter_t*)(mtag+1) = filter_ref;
		m_tag_prepend(m, mtag);
	}
	
	if (options && (options->ippo_flags & IPPOF_MCAST_OPTS)) {
		imo = &ip_moptions;
		
		bzero(imo, sizeof(struct ip6_moptions));
		imo->imo_multicast_ifp = options->ippo_mcast_ifnet;
		imo->imo_multicast_ttl = options->ippo_mcast_ttl;
		imo->imo_multicast_loop = options->ippo_mcast_loop;
	}
	
	/* Fill out a route structure and get a route */
	bzero(&ro, sizeof(struct route));
	sin->sin_len = sizeof(struct sockaddr_in);
	sin->sin_family = AF_INET;
	sin->sin_port = 0;
	sin->sin_addr = ip->ip_dst;
	rtalloc(&ro);
	if (ro.ro_rt == NULL) {
		m_freem(m);
		return ENETUNREACH;
	}
	/* Send  */
	error = ip_output(m, NULL, &ro, IP_ALLOWBROADCAST | IP_RAWOUTPUT, imo);
	
	/* Release the route */
	if (ro.ro_rt)
		rtfree(ro.ro_rt);
	
	return error;
}

static errno_t
ipf_injectv6_out(
	mbuf_t data,
	ipfilter_t filter_ref,
	ipf_pktopts_t options)
{
	struct route_in6 ro;
	struct sockaddr_in6	*sin6 = &ro.ro_dst;
	struct ip6_hdr	*ip6;
	struct mbuf	*m = (struct mbuf*)data;
	errno_t error = 0;
	struct m_tag *mtag = 0;
	struct ip6_moptions *im6o = 0, ip6_moptions;
	
	/* 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 = (struct ip6_hdr*)m_mtod(m);

	if (filter_ref != 0) {
		mtag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
					 	   sizeof (ipfilter_t), M_NOWAIT);
		if (mtag == NULL) {
			m_freem(m);
			return ENOMEM;
		}
		*(ipfilter_t*)(mtag+1) = filter_ref;
		m_tag_prepend(m, mtag);
	}
	
	if (options && (options->ippo_flags & IPPOF_MCAST_OPTS)) {
		im6o = &ip6_moptions;
		
		bzero(im6o, sizeof(struct ip6_moptions));
		im6o->im6o_multicast_ifp = options->ippo_mcast_ifnet;
		im6o->im6o_multicast_hlim = options->ippo_mcast_ttl;
		im6o->im6o_multicast_loop = options->ippo_mcast_loop;
	}
	
	
	/* Fill out a route structure and get a route */
	bzero(&ro, sizeof(struct route_in6));
	sin6->sin6_len = sizeof(struct sockaddr_in6);
	sin6->sin6_family = AF_INET6;
	sin6->sin6_addr = ip6->ip6_dst;
#if 0
	/* This is breaks loopback multicast! */
	/* The scope ID should already at s6_addr16[1] */
	if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
		/* Hack, pull the scope_id out of the dest addr */
		sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
		ip6->ip6_dst.s6_addr16[1] = 0;
	} else
		sin6->sin6_scope_id = 0;
#endif
	rtalloc((struct route*)&ro);
	if (ro.ro_rt == NULL) {
		m_freem(m);
		return ENETUNREACH;
	}
	
	/* Send  */
	error = ip6_output(m, NULL, &ro, 0, im6o, NULL, 0);
	
	/* Release the route */
	if (ro.ro_rt)
		rtfree(ro.ro_rt);
	
	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;

	/* 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:	
	return error;
}

__private_extern__ ipfilter_t
ipf_get_inject_filter(struct mbuf *m)
{
	ipfilter_t filter_ref = 0;
	struct m_tag *mtag;
	
	mtag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT, NULL);
	if (mtag) {
		filter_ref = *(ipfilter_t *)(mtag+1);
		
		m_tag_delete(m, mtag);
	}
	return filter_ref;
}

__private_extern__ int
ipf_init(void)
{
	int error = 0;
	lck_grp_attr_t *grp_attributes = 0;
	lck_attr_t *lck_attributes = 0;
	lck_grp_t *lck_grp = 0;
	
	grp_attributes = lck_grp_attr_alloc_init();
	if (grp_attributes == 0) {
		printf("ipf_init: lck_grp_attr_alloc_init failed\n");
		error = ENOMEM;
		goto done;
	}
	lck_grp_attr_setdefault(grp_attributes);
	
	lck_grp = lck_grp_alloc_init("IP Filter", grp_attributes);
	if (lck_grp == 0) {
		printf("ipf_init: lck_grp_alloc_init failed\n");
		error = ENOMEM;
		goto done;
	}
	
	lck_attributes = lck_attr_alloc_init();
	if (lck_attributes == 0) {
		printf("ipf_init: lck_attr_alloc_init failed\n");
		error = ENOMEM;
		goto done;
	}
	lck_attr_setdefault(lck_attributes);
	
	kipf_lock = lck_mtx_alloc_init(lck_grp, lck_attributes);
	if (kipf_lock == 0) {
		printf("ipf_init: lck_mtx_alloc_init failed\n");
		error = ENOMEM;
		goto done;
	}
	done:
	if (error != 0) {
		if (kipf_lock) {
			lck_mtx_free(kipf_lock, lck_grp);
			kipf_lock = 0;
		}
	}
	if (lck_grp) {
		lck_grp_free(lck_grp);
		lck_grp = 0;
	}
	if (grp_attributes) {
		lck_grp_attr_free(grp_attributes);
		grp_attributes = 0;
	}
	if (lck_attributes) {
		lck_attr_free(lck_attributes);
		lck_attributes = 0;
	}
	
	return error;
}
Commit	Line	Data
91447636	1	/*
8ad349bb	2	* Copyright (c) 2006 Apple Computer, Inc. All Rights Reserved.
91447636	3	*
8ad349bb	4	* @APPLE_LICENSE_OSREFERENCE_HEADER_START@
91447636	5	*
8ad349bb A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the
	10	* License may not be used to create, or enable the creation or
	11	* redistribution of, unlawful or unlicensed copies of an Apple operating
	12	* system, or to circumvent, violate, or enable the circumvention or
	13	* violation of, any terms of an Apple operating system software license
	14	* agreement.
	15	*
	16	* Please obtain a copy of the License at
	17	* http://www.opensource.apple.com/apsl/ and read it before using this
	18	* file.
	19	*
	20	* The Original Code and all software distributed under the License are
	21	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	22	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	23	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	24	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	25	* Please see the License for the specific language governing rights and
	26	* limitations under the License.
	27	*
	28	* @APPLE_LICENSE_OSREFERENCE_HEADER_END@
91447636 A	29	*/
	30
	31	#include <sys/param.h> /* for definition of NULL */
	32	#include <sys/errno.h>
	33	#include <sys/malloc.h>
	34	#include <sys/socket.h>
	35	#include <sys/mbuf.h>
	36	#include <sys/systm.h>
	37
	38	#define _IP_VHL
	39	#include <net/if_var.h>
	40	#include <net/route.h>
	41	#include <net/kpi_protocol.h>
	42
	43	#include <netinet/in_systm.h>
	44	#include <netinet/in.h>
	45	#include <netinet/in_var.h>
	46	#include <netinet6/in6_var.h>
	47	#include <netinet/ip.h>
	48	#include <netinet/ip6.h>
	49	#include <netinet/ip_var.h>
	50	#include <netinet6/ip6_var.h>
	51	#include <netinet/kpi_ipfilter_var.h>
	52
	53	/*
	54	* kipf_lock and kipf_ref protect the linkage of the list of IP filters
	55	* An IP filter can be removed only when kipf_ref is zero
	56	* If an IP filter cannot be removed because kipf_ref is not null, then
	57	* the IP filter is marjed and kipf_delayed_remove is set so that when
	58	* kipf_ref eventually goes down to zero, the IP filter is removed
	59	*/
	60	static lck_mtx_t *kipf_lock = 0;
	61	static unsigned long kipf_ref = 0;
	62	static unsigned long kipf_delayed_remove = 0;
	63
	64	__private_extern__ struct ipfilter_list ipv4_filters = TAILQ_HEAD_INITIALIZER(ipv4_filters);
	65	__private_extern__ struct ipfilter_list ipv6_filters = TAILQ_HEAD_INITIALIZER(ipv6_filters);
	66	__private_extern__ struct ipfilter_list tbr_filters = TAILQ_HEAD_INITIALIZER(tbr_filters);
	67
	68	__private_extern__ void
	69	ipf_ref(void)
	70	{
	71	lck_mtx_lock(kipf_lock);
	72	kipf_ref++;
	73	lck_mtx_unlock(kipf_lock);
	74	}
	75
	76	__private_extern__ void
	77	ipf_unref(void)
	78	{
	79	lck_mtx_lock(kipf_lock);
	80
	81	if (kipf_ref == 0)
	82	panic("ipf_unref: kipf_ref == 0\n");
	83
	84	kipf_ref--;
	85	if (kipf_ref == 0 && kipf_delayed_remove != 0) {
	86	struct ipfilter *filter;
	87
	88	while ((filter = TAILQ_FIRST(&tbr_filters))) {
	89	ipf_detach_func ipf_detach = filter->ipf_filter.ipf_detach;
	90	void* cookie = filter->ipf_filter.cookie;
	91
	92	TAILQ_REMOVE(filter->ipf_head, filter, ipf_link);
93	TAILQ_REMOVE(&tbr_filters, filter, ipf_tbr);
94	kipf_delayed_remove--;
95
96	if (ipf_detach) {
97	lck_mtx_unlock(kipf_lock);
98	ipf_detach(cookie);
99	lck_mtx_lock(kipf_lock);
100	/* In case some filter got to run while we released the lock */
101	if (kipf_ref != 0)
102	break;
103	}
104	}
105	}
106	lck_mtx_unlock(kipf_lock);
107	}
108
109	static errno_t
110	ipf_add(
111	const struct ipf_filter* filter,
112	ipfilter_t *filter_ref,
113	struct ipfilter_list *head)
114	{
115	struct ipfilter *new_filter;
116	if (filter->name == NULL \|\| (filter->ipf_input == NULL && filter->ipf_output == NULL))
117	return EINVAL;
118
119	MALLOC(new_filter, struct ipfilter, sizeof(new_filter), M_IFADDR, M_WAITOK);
120	if (new_filter == NULL)
121	return ENOMEM;
122
123	lck_mtx_lock(kipf_lock);
124	new_filter->ipf_filter = *filter;
125	new_filter->ipf_head = head;
126
127	/*
128	* 3957298
129	* Make sure third parties have a chance to filter packets before
130	* SharedIP. Always SharedIP at the end of the list.
131	*/
132	if (filter->name != NULL &&
133	strcmp(filter->name, "com.apple.nke.SharedIP") == 0) {
134	TAILQ_INSERT_TAIL(head, new_filter, ipf_link);
135	}
136	else {
137	TAILQ_INSERT_HEAD(head, new_filter, ipf_link);
138	}
139
140	lck_mtx_unlock(kipf_lock);
141
142	*filter_ref = (ipfilter_t)new_filter;
143	return 0;
144	}
145
146	errno_t
147	ipf_addv4(
148	const struct ipf_filter* filter,
149	ipfilter_t *filter_ref)
150	{
151	return ipf_add(filter, filter_ref, &ipv4_filters);
152	}
153
154	errno_t
155	ipf_addv6(
156	const struct ipf_filter* filter,
157	ipfilter_t *filter_ref)
158	{
159	return ipf_add(filter, filter_ref, &ipv6_filters);
160	}
161
162	errno_t
163	ipf_remove(
164	ipfilter_t filter_ref)
165	{
166	struct ipfilter match = (struct ipfilter)filter_ref;
167	struct ipfilter_list *head;
168
169	if (match == 0 \|\| (match->ipf_head != &ipv4_filters && match->ipf_head != &ipv6_filters))
170	return EINVAL;
171
172	head = match->ipf_head;
173
174	lck_mtx_lock(kipf_lock);
175	TAILQ_FOREACH(match, head, ipf_link) {
176	if (match == (struct ipfilter*)filter_ref) {
177	ipf_detach_func ipf_detach = match->ipf_filter.ipf_detach;
178	void* cookie = match->ipf_filter.cookie;
179
180	/*
181	* Cannot detach when they are filters running
182	*/
183	if (kipf_ref) {
184	kipf_delayed_remove++;
185	TAILQ_INSERT_TAIL(&tbr_filters, match, ipf_tbr);
186	match->ipf_filter.ipf_input = 0;
187	match->ipf_filter.ipf_output = 0;
188	lck_mtx_unlock(kipf_lock);
189	} else {
190	TAILQ_REMOVE(head, match, ipf_link);
191	lck_mtx_unlock(kipf_lock);
192	if (ipf_detach)
193	ipf_detach(cookie);
194	FREE(match, M_IFADDR);
195	}
196	return 0;
197	}
198	}
199	lck_mtx_unlock(kipf_lock);
200
201	return ENOENT;
202	}
203
204	int log_for_en1 = 0;
205
206	errno_t
207	ipf_inject_input(
208	mbuf_t data,
209	ipfilter_t filter_ref)
210	{
211	struct mbuf m = (struct mbuf)data;
212	struct m_tag *mtag = 0;
213	struct ip ip = mtod(m, struct ip );
214	u_int8_t vers;
215	int hlen;
216	errno_t error = 0;
217	protocol_family_t proto;
218
219	vers = IP_VHL_V(ip->ip_vhl);
220
221	switch (vers) {
222	case 4:
223	proto = PF_INET;
224	break;
225	case 6:
226	proto = PF_INET6;
227	break;
228	default:
229	error = ENOTSUP;
230	goto done;
231	}
232
233	if (filter_ref == 0 && m->m_pkthdr.rcvif == 0) {
234	m->m_pkthdr.rcvif = ifunit("lo0");
235	m->m_pkthdr.csum_data = 0;
236	m->m_pkthdr.csum_flags = 0;
237	if (vers == 4) {
238	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
239	ip->ip_sum = 0;
240	ip->ip_sum = in_cksum(m, hlen);
241	}
242	}
243	if (filter_ref != 0) {
244	mtag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
245	sizeof (ipfilter_t), M_NOWAIT);
246	if (mtag == NULL) {
247	error = ENOMEM;
248	goto done;
249	}
250	(ipfilter_t)(mtag+1) = filter_ref;
251	m_tag_prepend(m, mtag);
252	}
253
254	error = proto_inject(proto, data);
255
256	done:
257	return error;
258	}
259
260	static errno_t
261	ipf_injectv4_out(
262	mbuf_t data,
263	ipfilter_t filter_ref,
264	ipf_pktopts_t options)
265	{
266	struct route ro;
267	struct sockaddr_in sin = (struct sockaddr_in)&ro.ro_dst;
268	struct ip *ip;
269	struct mbuf m = (struct mbuf)data;
270	errno_t error = 0;
271	struct m_tag *mtag = 0;
272	struct ip_moptions *imo = 0, ip_moptions;
273
274	/* Make the IP header contiguous in the mbuf */
275	if ((size_t)m->m_len < sizeof(struct ip)) {
276	m = m_pullup(m, sizeof(struct ip));
277	if (m == NULL) return ENOMEM;
278	}
279	ip = (struct ip*)m_mtod(m);
280
281	if (filter_ref != 0) {
282	mtag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
283	sizeof (ipfilter_t), M_NOWAIT);
284	if (mtag == NULL) {
285	m_freem(m);
286	return ENOMEM;
287	}
288	(ipfilter_t)(mtag+1) = filter_ref;
289	m_tag_prepend(m, mtag);
290	}
291
292	if (options && (options->ippo_flags & IPPOF_MCAST_OPTS)) {
293	imo = &ip_moptions;
294
295	bzero(imo, sizeof(struct ip6_moptions));
296	imo->imo_multicast_ifp = options->ippo_mcast_ifnet;
297	imo->imo_multicast_ttl = options->ippo_mcast_ttl;
298	imo->imo_multicast_loop = options->ippo_mcast_loop;
299	}
300
301	/* Fill out a route structure and get a route */
302	bzero(&ro, sizeof(struct route));
303	sin->sin_len = sizeof(struct sockaddr_in);
304	sin->sin_family = AF_INET;
305	sin->sin_port = 0;
306	sin->sin_addr = ip->ip_dst;
307	rtalloc(&ro);
308	if (ro.ro_rt == NULL) {
309	m_freem(m);
310	return ENETUNREACH;
311	}
312	/* Send */
313	error = ip_output(m, NULL, &ro, IP_ALLOWBROADCAST \| IP_RAWOUTPUT, imo);
314
315	/* Release the route */
316	if (ro.ro_rt)
317	rtfree(ro.ro_rt);
318
319	return error;
320	}
321
322	static errno_t
323	ipf_injectv6_out(
324	mbuf_t data,
325	ipfilter_t filter_ref,
326	ipf_pktopts_t options)
327	{
328	struct route_in6 ro;
329	struct sockaddr_in6 *sin6 = &ro.ro_dst;
330	struct ip6_hdr *ip6;
331	struct mbuf m = (struct mbuf)data;
332	errno_t error = 0;
333	struct m_tag *mtag = 0;
334	struct ip6_moptions *im6o = 0, ip6_moptions;
335
336	/* Make the IP header contiguous in the mbuf */
337	if ((size_t)m->m_len < sizeof(struct ip6_hdr)) {
338	m = m_pullup(m, sizeof(struct ip6_hdr));
339	if (m == NULL) return ENOMEM;
340	}
341	ip6 = (struct ip6_hdr*)m_mtod(m);
342
343	if (filter_ref != 0) {
344	mtag = m_tag_alloc(KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT,
345	sizeof (ipfilter_t), M_NOWAIT);
346	if (mtag == NULL) {
347	m_freem(m);
348	return ENOMEM;
349	}
350	(ipfilter_t)(mtag+1) = filter_ref;
351	m_tag_prepend(m, mtag);
352	}
353
354	if (options && (options->ippo_flags & IPPOF_MCAST_OPTS)) {
355	im6o = &ip6_moptions;
356
357	bzero(im6o, sizeof(struct ip6_moptions));
358	im6o->im6o_multicast_ifp = options->ippo_mcast_ifnet;
359	im6o->im6o_multicast_hlim = options->ippo_mcast_ttl;
360	im6o->im6o_multicast_loop = options->ippo_mcast_loop;
361	}
362
363
364	/* Fill out a route structure and get a route */
365	bzero(&ro, sizeof(struct route_in6));
366	sin6->sin6_len = sizeof(struct sockaddr_in6);
367	sin6->sin6_family = AF_INET6;
368	sin6->sin6_addr = ip6->ip6_dst;
369	#if 0
370	/* This is breaks loopback multicast! */
371	/* The scope ID should already at s6_addr16[1] */
372	if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
373	/* Hack, pull the scope_id out of the dest addr */
374	sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
375	ip6->ip6_dst.s6_addr16[1] = 0;
376	} else
377	sin6->sin6_scope_id = 0;
378	#endif
379	rtalloc((struct route*)&ro);
380	if (ro.ro_rt == NULL) {
381	m_freem(m);
382	return ENETUNREACH;
383	}
384
385	/* Send */
386	error = ip6_output(m, NULL, &ro, 0, im6o, NULL, 0);
387
388	/* Release the route */
389	if (ro.ro_rt)
390	rtfree(ro.ro_rt);
391
392	return error;
393	}
394
395	errno_t
396	ipf_inject_output(
397	mbuf_t data,
398	ipfilter_t filter_ref,
399	ipf_pktopts_t options)
400	{
401	struct mbuf m = (struct mbuf)data;
402	u_int8_t vers;
403	errno_t error = 0;
404
405	/* Make one byte of the header contiguous in the mbuf */
406	if (m->m_len < 1) {
407	m = m_pullup(m, 1);
408	if (m == NULL)
409	goto done;
410	}
411
412	vers = ((u_int8_t)m_mtod(m)) >> 4;
413	switch (vers)
414	{
415	case 4:
416	error = ipf_injectv4_out(data, filter_ref, options);
417	break;
418	case 6:
419	error = ipf_injectv6_out(data, filter_ref, options);
420	break;
421	default:
422	m_freem(m);
423	error = ENOTSUP;
424	break;
425	}
426
427	done:
428	return error;
429	}
430
431	__private_extern__ ipfilter_t
432	ipf_get_inject_filter(struct mbuf *m)
433	{
434	ipfilter_t filter_ref = 0;
435	struct m_tag *mtag;
436
437	mtag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, KERNEL_TAG_TYPE_IPFILT, NULL);
438	if (mtag) {
439	filter_ref = (ipfilter_t )(mtag+1);
440
441	m_tag_delete(m, mtag);
442	}
443	return filter_ref;
444	}
445
446	__private_extern__ int
447	ipf_init(void)
448	{
449	int error = 0;
450	lck_grp_attr_t *grp_attributes = 0;
451	lck_attr_t *lck_attributes = 0;
452	lck_grp_t *lck_grp = 0;
453
454	grp_attributes = lck_grp_attr_alloc_init();
455	if (grp_attributes == 0) {
456	printf("ipf_init: lck_grp_attr_alloc_init failed\n");
457	error = ENOMEM;
458	goto done;
459	}
8ad349bb	460	lck_grp_attr_setdefault(grp_attributes);
91447636 A	461
	462	lck_grp = lck_grp_alloc_init("IP Filter", grp_attributes);
	463	if (lck_grp == 0) {
	464	printf("ipf_init: lck_grp_alloc_init failed\n");
	465	error = ENOMEM;
	466	goto done;
	467	}
	468
	469	lck_attributes = lck_attr_alloc_init();
	470	if (lck_attributes == 0) {
	471	printf("ipf_init: lck_attr_alloc_init failed\n");
	472	error = ENOMEM;
	473	goto done;
	474	}
8ad349bb	475	lck_attr_setdefault(lck_attributes);
91447636 A	476
	477	kipf_lock = lck_mtx_alloc_init(lck_grp, lck_attributes);
	478	if (kipf_lock == 0) {
	479	printf("ipf_init: lck_mtx_alloc_init failed\n");
	480	error = ENOMEM;
	481	goto done;
	482	}
	483	done:
	484	if (error != 0) {
	485	if (kipf_lock) {
	486	lck_mtx_free(kipf_lock, lck_grp);
	487	kipf_lock = 0;
	488	}
	489	}
	490	if (lck_grp) {
	491	lck_grp_free(lck_grp);
	492	lck_grp = 0;
	493	}
	494	if (grp_attributes) {
	495	lck_grp_attr_free(grp_attributes);
	496	grp_attributes = 0;
	497	}
	498	if (lck_attributes) {
	499	lck_attr_free(lck_attributes);
	500	lck_attributes = 0;
	501	}
	502
	503	return error;
	504	}