xref: /freebsd/sys/netinet/ip_var.h (revision 724b4bfdf1306e4f2c451b6d146fe0fe0353b2c8)
1 /*-
2  * Copyright (c) 1982, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)ip_var.h	8.2 (Berkeley) 1/9/95
30  * $FreeBSD$
31  */
32 
33 #ifndef _NETINET_IP_VAR_H_
34 #define	_NETINET_IP_VAR_H_
35 
36 #include <sys/queue.h>
37 
38 /*
39  * Overlay for ip header used by other protocols (tcp, udp).
40  */
41 struct ipovly {
42 	u_char	ih_x1[9];		/* (unused) */
43 	u_char	ih_pr;			/* protocol */
44 	u_short	ih_len;			/* protocol length */
45 	struct	in_addr ih_src;		/* source internet address */
46 	struct	in_addr ih_dst;		/* destination internet address */
47 };
48 
49 #ifdef _KERNEL
50 /*
51  * Ip reassembly queue structure.  Each fragment
52  * being reassembled is attached to one of these structures.
53  * They are timed out after ipq_ttl drops to 0, and may also
54  * be reclaimed if memory becomes tight.
55  */
56 struct ipq {
57 	TAILQ_ENTRY(ipq) ipq_list;	/* to other reass headers */
58 	u_char	ipq_ttl;		/* time for reass q to live */
59 	u_char	ipq_p;			/* protocol of this fragment */
60 	u_short	ipq_id;			/* sequence id for reassembly */
61 	struct mbuf *ipq_frags;		/* to ip headers of fragments */
62 	struct	in_addr ipq_src,ipq_dst;
63 	u_char	ipq_nfrags;		/* # frags in this packet */
64 	struct label *ipq_label;	/* MAC label */
65 };
66 #endif /* _KERNEL */
67 
68 /*
69  * Structure stored in mbuf in inpcb.ip_options
70  * and passed to ip_output when ip options are in use.
71  * The actual length of the options (including ipopt_dst)
72  * is in m_len.
73  */
74 #define MAX_IPOPTLEN	40
75 
76 struct ipoption {
77 	struct	in_addr ipopt_dst;	/* first-hop dst if source routed */
78 	char	ipopt_list[MAX_IPOPTLEN];	/* options proper */
79 };
80 
81 /*
82  * Structure attached to inpcb.ip_moptions and
83  * passed to ip_output when IP multicast options are in use.
84  * This structure is lazy-allocated.
85  */
86 struct ip_moptions {
87 	struct	ifnet *imo_multicast_ifp; /* ifp for outgoing multicasts */
88 	struct in_addr imo_multicast_addr; /* ifindex/addr on MULTICAST_IF */
89 	u_long	imo_multicast_vif;	/* vif num outgoing multicasts */
90 	u_char	imo_multicast_ttl;	/* TTL for outgoing multicasts */
91 	u_char	imo_multicast_loop;	/* 1 => hear sends if a member */
92 	u_short	imo_num_memberships;	/* no. memberships this socket */
93 	u_short	imo_max_memberships;	/* max memberships this socket */
94 	struct	in_multi **imo_membership;	/* group memberships */
95 	struct	in_mfilter *imo_mfilters;	/* source filters */
96 	STAILQ_ENTRY(ip_moptions) imo_link;
97 };
98 
99 struct	ipstat {
100 	u_long	ips_total;		/* total packets received */
101 	u_long	ips_badsum;		/* checksum bad */
102 	u_long	ips_tooshort;		/* packet too short */
103 	u_long	ips_toosmall;		/* not enough data */
104 	u_long	ips_badhlen;		/* ip header length < data size */
105 	u_long	ips_badlen;		/* ip length < ip header length */
106 	u_long	ips_fragments;		/* fragments received */
107 	u_long	ips_fragdropped;	/* frags dropped (dups, out of space) */
108 	u_long	ips_fragtimeout;	/* fragments timed out */
109 	u_long	ips_forward;		/* packets forwarded */
110 	u_long	ips_fastforward;	/* packets fast forwarded */
111 	u_long	ips_cantforward;	/* packets rcvd for unreachable dest */
112 	u_long	ips_redirectsent;	/* packets forwarded on same net */
113 	u_long	ips_noproto;		/* unknown or unsupported protocol */
114 	u_long	ips_delivered;		/* datagrams delivered to upper level*/
115 	u_long	ips_localout;		/* total ip packets generated here */
116 	u_long	ips_odropped;		/* lost packets due to nobufs, etc. */
117 	u_long	ips_reassembled;	/* total packets reassembled ok */
118 	u_long	ips_fragmented;		/* datagrams successfully fragmented */
119 	u_long	ips_ofragments;		/* output fragments created */
120 	u_long	ips_cantfrag;		/* don't fragment flag was set, etc. */
121 	u_long	ips_badoptions;		/* error in option processing */
122 	u_long	ips_noroute;		/* packets discarded due to no route */
123 	u_long	ips_badvers;		/* ip version != 4 */
124 	u_long	ips_rawout;		/* total raw ip packets generated */
125 	u_long	ips_toolong;		/* ip length > max ip packet size */
126 	u_long	ips_notmember;		/* multicasts for unregistered grps */
127 	u_long	ips_nogif;		/* no match gif found */
128 	u_long	ips_badaddr;		/* invalid address on header */
129 };
130 
131 #ifdef _KERNEL
132 
133 #include <net/vnet.h>
134 
135 /*
136  * In-kernel consumers can use these accessor macros directly to update
137  * stats.
138  */
139 #define	IPSTAT_ADD(name, val)	V_ipstat.name += (val)
140 #define	IPSTAT_SUB(name, val)	V_ipstat.name -= (val)
141 #define	IPSTAT_INC(name)	IPSTAT_ADD(name, 1)
142 #define	IPSTAT_DEC(name)	IPSTAT_SUB(name, 1)
143 
144 /*
145  * Kernel module consumers must use this accessor macro.
146  */
147 void	kmod_ipstat_inc(int statnum);
148 #define	KMOD_IPSTAT_INC(name)						\
149 	kmod_ipstat_inc(offsetof(struct ipstat, name) / sizeof(u_long))
150 void	kmod_ipstat_dec(int statnum);
151 #define	KMOD_IPSTAT_DEC(name)						\
152 	kmod_ipstat_dec(offsetof(struct ipstat, name) / sizeof(u_long))
153 
154 /* flags passed to ip_output as last parameter */
155 #define	IP_FORWARDING		0x1		/* most of ip header exists */
156 #define	IP_RAWOUTPUT		0x2		/* raw ip header exists */
157 #define	IP_SENDONES		0x4		/* send all-ones broadcast */
158 #define	IP_SENDTOIF		0x8		/* send on specific ifnet */
159 #define IP_ROUTETOIF		SO_DONTROUTE	/* 0x10 bypass routing tables */
160 #define IP_ALLOWBROADCAST	SO_BROADCAST	/* 0x20 can send broadcast packets */
161 
162 /*
163  * mbuf flag used by ip_fastfwd
164  */
165 #define	M_FASTFWD_OURS		M_PROTO1	/* changed dst to local */
166 
167 #ifdef __NO_STRICT_ALIGNMENT
168 #define IP_HDR_ALIGNED_P(ip)	1
169 #else
170 #define IP_HDR_ALIGNED_P(ip)	((((intptr_t) (ip)) & 3) == 0)
171 #endif
172 
173 struct ip;
174 struct inpcb;
175 struct route;
176 struct sockopt;
177 
178 VNET_DECLARE(struct ipstat, ipstat);
179 VNET_DECLARE(u_short, ip_id);			/* ip packet ctr, for ids */
180 VNET_DECLARE(int, ip_defttl);			/* default IP ttl */
181 VNET_DECLARE(int, ipforwarding);		/* ip forwarding */
182 #ifdef IPSTEALTH
183 VNET_DECLARE(int, ipstealth);			/* stealth forwarding */
184 #endif
185 extern u_char	ip_protox[];
186 VNET_DECLARE(struct socket *, ip_rsvpd);	/* reservation protocol daemon*/
187 VNET_DECLARE(struct socket *, ip_mrouter);	/* multicast routing daemon */
188 extern int	(*legal_vif_num)(int);
189 extern u_long	(*ip_mcast_src)(int);
190 VNET_DECLARE(int, rsvp_on);
191 VNET_DECLARE(int, drop_redirect);
192 extern struct	pr_usrreqs rip_usrreqs;
193 
194 #define	V_ipstat		VNET(ipstat)
195 #define	V_ip_id			VNET(ip_id)
196 #define	V_ip_defttl		VNET(ip_defttl)
197 #define	V_ipforwarding		VNET(ipforwarding)
198 #ifdef IPSTEALTH
199 #define	V_ipstealth		VNET(ipstealth)
200 #endif
201 #define	V_ip_rsvpd		VNET(ip_rsvpd)
202 #define	V_ip_mrouter		VNET(ip_mrouter)
203 #define	V_rsvp_on		VNET(rsvp_on)
204 #define	V_drop_redirect		VNET(drop_redirect)
205 
206 void	inp_freemoptions(struct ip_moptions *);
207 int	inp_getmoptions(struct inpcb *, struct sockopt *);
208 int	inp_setmoptions(struct inpcb *, struct sockopt *);
209 
210 int	ip_ctloutput(struct socket *, struct sockopt *sopt);
211 void	ip_drain(void);
212 int	ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
213 	    u_long if_hwassist_flags, int sw_csum);
214 void	ip_forward(struct mbuf *m, int srcrt);
215 void	ip_init(void);
216 #ifdef VIMAGE
217 void	ip_destroy(void);
218 #endif
219 extern int
220 	(*ip_mforward)(struct ip *, struct ifnet *, struct mbuf *,
221 	    struct ip_moptions *);
222 int	ip_output(struct mbuf *,
223 	    struct mbuf *, struct route *, int, struct ip_moptions *,
224 	    struct inpcb *);
225 int	ipproto_register(short);
226 int	ipproto_unregister(short);
227 struct mbuf *
228 	ip_reass(struct mbuf *);
229 struct in_ifaddr *
230 	ip_rtaddr(struct in_addr, u_int fibnum);
231 void	ip_savecontrol(struct inpcb *, struct mbuf **, struct ip *,
232 	    struct mbuf *);
233 void	ip_slowtimo(void);
234 u_int16_t	ip_randomid(void);
235 int	rip_ctloutput(struct socket *, struct sockopt *);
236 void	rip_ctlinput(int, struct sockaddr *, void *);
237 void	rip_init(void);
238 #ifdef VIMAGE
239 void	rip_destroy(void);
240 #endif
241 void	rip_input(struct mbuf *, int);
242 int	rip_output(struct mbuf *, struct socket *, u_long);
243 void	ipip_input(struct mbuf *, int);
244 void	rsvp_input(struct mbuf *, int);
245 int	ip_rsvp_init(struct socket *);
246 int	ip_rsvp_done(void);
247 extern int	(*ip_rsvp_vif)(struct socket *, struct sockopt *);
248 extern void	(*ip_rsvp_force_done)(struct socket *);
249 extern void	(*rsvp_input_p)(struct mbuf *m, int off);
250 
251 VNET_DECLARE(struct pfil_head, inet_pfil_hook);	/* packet filter hooks */
252 #define	V_inet_pfil_hook	VNET(inet_pfil_hook)
253 
254 void	in_delayed_cksum(struct mbuf *m);
255 
256 /* Hooks for ipfw, dummynet, divert etc. Most are declared in raw_ip.c */
257 /*
258  * Reference to an ipfw or packet filter rule that can be carried
259  * outside critical sections.
260  * A rule is identified by rulenum:rule_id which is ordered.
261  * In version chain_id the rule can be found in slot 'slot', so
262  * we don't need a lookup if chain_id == chain->id.
263  *
264  * On exit from the firewall this structure refers to the rule after
265  * the matching one (slot points to the new rule; rulenum:rule_id-1
266  * is the matching rule), and additional info (e.g. info often contains
267  * the insn argument or tablearg in the low 16 bits, in host format).
268  * On entry, the structure is valid if slot>0, and refers to the starting
269  * rules. 'info' contains the reason for reinject, e.g. divert port,
270  * divert direction, and so on.
271  */
272 struct ipfw_rule_ref {
273 	uint32_t	slot;		/* slot for matching rule	*/
274 	uint32_t	rulenum;	/* matching rule number		*/
275 	uint32_t	rule_id;	/* matching rule id		*/
276 	uint32_t	chain_id;	/* ruleset id			*/
277 	uint32_t	info;		/* see below			*/
278 };
279 
280 enum {
281 	IPFW_INFO_MASK	= 0x0000ffff,
282 	IPFW_INFO_OUT	= 0x00000000,	/* outgoing, just for convenience */
283 	IPFW_INFO_IN	= 0x80000000,	/* incoming, overloads dir */
284 	IPFW_ONEPASS	= 0x40000000,	/* One-pass, do not reinject */
285 	IPFW_IS_MASK	= 0x30000000,	/* which source ? */
286 	IPFW_IS_DIVERT	= 0x20000000,
287 	IPFW_IS_DUMMYNET =0x10000000,
288 	IPFW_IS_PIPE	= 0x08000000,	/* pip1=1, queue = 0 */
289 };
290 #define MTAG_IPFW	1148380143	/* IPFW-tagged cookie */
291 #define MTAG_IPFW_RULE	1262273568	/* rule reference */
292 #define	MTAG_IPFW_CALL	1308397630	/* call stack */
293 
294 struct ip_fw_args;
295 typedef int	(*ip_fw_chk_ptr_t)(struct ip_fw_args *args);
296 typedef int	(*ip_fw_ctl_ptr_t)(struct sockopt *);
297 VNET_DECLARE(ip_fw_ctl_ptr_t, ip_fw_ctl_ptr);
298 #define	V_ip_fw_ctl_ptr		VNET(ip_fw_ctl_ptr)
299 
300 /* Divert hooks. */
301 extern void	(*ip_divert_ptr)(struct mbuf *m, int incoming);
302 /* ng_ipfw hooks -- XXX make it the same as divert and dummynet */
303 extern int	(*ng_ipfw_input_p)(struct mbuf **, int,
304 			struct ip_fw_args *, int);
305 
306 extern int	(*ip_dn_ctl_ptr)(struct sockopt *);
307 extern int	(*ip_dn_io_ptr)(struct mbuf **, int, struct ip_fw_args *);
308 
309 VNET_DECLARE(int, ip_do_randomid);
310 #define	V_ip_do_randomid	VNET(ip_do_randomid)
311 #define	ip_newid()	((V_ip_do_randomid != 0) ? ip_randomid() : \
312 			    htons(V_ip_id++))
313 
314 #endif /* _KERNEL */
315 
316 #endif /* !_NETINET_IP_VAR_H_ */
317