xref: /freebsd-13-stable/sys/netinet/ip_var.h (revision 4b40a16f0d188422227478889b38cc341d50f88f)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)ip_var.h	8.2 (Berkeley) 1/9/95
32  */
33 
34 #ifndef _NETINET_IP_VAR_H_
35 #define	_NETINET_IP_VAR_H_
36 
37 #include <sys/queue.h>
38 #include <sys/epoch.h>
39 
40 /*
41  * Overlay for ip header used by other protocols (tcp, udp).
42  */
43 struct ipovly {
44 	u_char	ih_x1[9];		/* (unused) */
45 	u_char	ih_pr;			/* protocol */
46 	u_short	ih_len;			/* protocol length */
47 	struct	in_addr ih_src;		/* source internet address */
48 	struct	in_addr ih_dst;		/* destination internet address */
49 };
50 
51 #ifdef _KERNEL
52 /*
53  * Ip reassembly queue structure.  Each fragment
54  * being reassembled is attached to one of these structures.
55  * They are timed out after ipq_ttl drops to 0, and may also
56  * be reclaimed if memory becomes tight.
57  */
58 struct ipq {
59 	TAILQ_ENTRY(ipq) ipq_list;	/* to other reass headers */
60 	u_char	ipq_ttl;		/* time for reass q to live */
61 	u_char	ipq_p;			/* protocol of this fragment */
62 	u_short	ipq_id;			/* sequence id for reassembly */
63 	int	ipq_maxoff;		/* total length of packet */
64 	struct mbuf *ipq_frags;		/* to ip headers of fragments */
65 	struct	in_addr ipq_src,ipq_dst;
66 	u_char	ipq_nfrags;		/* # frags in this packet */
67 	struct label *ipq_label;	/* MAC label */
68 };
69 #endif /* _KERNEL */
70 
71 /*
72  * Structure stored in mbuf in inpcb.ip_options
73  * and passed to ip_output when ip options are in use.
74  * The actual length of the options (including ipopt_dst)
75  * is in m_len.
76  */
77 #define MAX_IPOPTLEN	40
78 
79 struct ipoption {
80 	struct	in_addr ipopt_dst;	/* first-hop dst if source routed */
81 	char	ipopt_list[MAX_IPOPTLEN];	/* options proper */
82 };
83 
84 #if defined(_NETINET_IN_VAR_H_) && defined(_KERNEL)
85 /*
86  * Structure attached to inpcb.ip_moptions and
87  * passed to ip_output when IP multicast options are in use.
88  * This structure is lazy-allocated.
89  */
90 struct ip_moptions {
91 	struct	ifnet *imo_multicast_ifp; /* ifp for outgoing multicasts */
92 	struct in_addr imo_multicast_addr; /* ifindex/addr on MULTICAST_IF */
93 	u_long	imo_multicast_vif;	/* vif num outgoing multicasts */
94 	u_char	imo_multicast_ttl;	/* TTL for outgoing multicasts */
95 	u_char	imo_multicast_loop;	/* 1 => hear sends if a member */
96 	struct ip_mfilter_head imo_head; /* group membership list */
97 };
98 #else
99 struct ip_moptions;
100 #endif
101 
102 struct	ipstat {
103 	uint64_t ips_total;		/* total packets received */
104 	uint64_t ips_badsum;		/* checksum bad */
105 	uint64_t ips_tooshort;		/* packet too short */
106 	uint64_t ips_toosmall;		/* not enough data */
107 	uint64_t ips_badhlen;		/* ip header length < data size */
108 	uint64_t ips_badlen;		/* ip length < ip header length */
109 	uint64_t ips_fragments;		/* fragments received */
110 	uint64_t ips_fragdropped;	/* frags dropped (dups, out of space) */
111 	uint64_t ips_fragtimeout;	/* fragments timed out */
112 	uint64_t ips_forward;		/* packets forwarded */
113 	uint64_t ips_fastforward;	/* packets fast forwarded */
114 	uint64_t ips_cantforward;	/* packets rcvd for unreachable dest */
115 	uint64_t ips_redirectsent;	/* packets forwarded on same net */
116 	uint64_t ips_noproto;		/* unknown or unsupported protocol */
117 	uint64_t ips_delivered;		/* datagrams delivered to upper level*/
118 	uint64_t ips_localout;		/* total ip packets generated here */
119 	uint64_t ips_odropped;		/* lost packets due to nobufs, etc. */
120 	uint64_t ips_reassembled;	/* total packets reassembled ok */
121 	uint64_t ips_fragmented;	/* datagrams successfully fragmented */
122 	uint64_t ips_ofragments;	/* output fragments created */
123 	uint64_t ips_cantfrag;		/* don't fragment flag was set, etc. */
124 	uint64_t ips_badoptions;		/* error in option processing */
125 	uint64_t ips_noroute;		/* packets discarded due to no route */
126 	uint64_t ips_badvers;		/* ip version != 4 */
127 	uint64_t ips_rawout;		/* total raw ip packets generated */
128 	uint64_t ips_toolong;		/* ip length > max ip packet size */
129 	uint64_t ips_notmember;		/* multicasts for unregistered grps */
130 	uint64_t ips_nogif;		/* no match gif found */
131 	uint64_t ips_badaddr;		/* invalid address on header */
132 };
133 
134 #ifdef _KERNEL
135 
136 #include <sys/counter.h>
137 #include <net/vnet.h>
138 
139 VNET_PCPUSTAT_DECLARE(struct ipstat, ipstat);
140 /*
141  * In-kernel consumers can use these accessor macros directly to update
142  * stats.
143  */
144 #define	IPSTAT_ADD(name, val)	\
145     VNET_PCPUSTAT_ADD(struct ipstat, ipstat, name, (val))
146 #define	IPSTAT_SUB(name, val)	IPSTAT_ADD(name, -(val))
147 #define	IPSTAT_INC(name)	IPSTAT_ADD(name, 1)
148 #define	IPSTAT_DEC(name)	IPSTAT_SUB(name, 1)
149 
150 /*
151  * Kernel module consumers must use this accessor macro.
152  */
153 void	kmod_ipstat_inc(int statnum);
154 #define	KMOD_IPSTAT_INC(name)	\
155     kmod_ipstat_inc(offsetof(struct ipstat, name) / sizeof(uint64_t))
156 void	kmod_ipstat_dec(int statnum);
157 #define	KMOD_IPSTAT_DEC(name)	\
158     kmod_ipstat_dec(offsetof(struct ipstat, name) / sizeof(uint64_t))
159 
160 /* flags passed to ip_output as last parameter */
161 #define	IP_FORWARDING		0x1		/* most of ip header exists */
162 #define	IP_RAWOUTPUT		0x2		/* raw ip header exists */
163 #define	IP_SENDONES		0x4		/* send all-ones broadcast */
164 #define	IP_SENDTOIF		0x8		/* send on specific ifnet */
165 #define IP_ROUTETOIF		SO_DONTROUTE	/* 0x10 bypass routing tables */
166 #define IP_ALLOWBROADCAST	SO_BROADCAST	/* 0x20 can send broadcast packets */
167 #define	IP_NODEFAULTFLOWID	0x40		/* Don't set the flowid from inp */
168 #define IP_NO_SND_TAG_RL	0x80		/* Don't send down the ratelimit tag */
169 
170 #ifdef __NO_STRICT_ALIGNMENT
171 #define IP_HDR_ALIGNED_P(ip)	1
172 #else
173 #define IP_HDR_ALIGNED_P(ip)	((((intptr_t) (ip)) & 3) == 0)
174 #endif
175 
176 struct ip;
177 struct inpcb;
178 struct route;
179 struct sockopt;
180 struct inpcbinfo;
181 
182 VNET_DECLARE(int, ip_defttl);			/* default IP ttl */
183 VNET_DECLARE(int, ipforwarding);		/* ip forwarding */
184 VNET_DECLARE(int, ipsendredirects);
185 #ifdef IPSTEALTH
186 VNET_DECLARE(int, ipstealth);			/* stealth forwarding */
187 #endif
188 extern u_char	ip_protox[];
189 VNET_DECLARE(struct socket *, ip_rsvpd);	/* reservation protocol daemon*/
190 VNET_DECLARE(struct socket *, ip_mrouter);	/* multicast routing daemon */
191 extern int	(*legal_vif_num)(int);
192 extern u_long	(*ip_mcast_src)(int);
193 VNET_DECLARE(int, rsvp_on);
194 VNET_DECLARE(int, drop_redirect);
195 extern struct	pr_usrreqs rip_usrreqs;
196 
197 #define	V_ip_id			VNET(ip_id)
198 #define	V_ip_defttl		VNET(ip_defttl)
199 #define	V_ipforwarding		VNET(ipforwarding)
200 #define	V_ipsendredirects	VNET(ipsendredirects)
201 #ifdef IPSTEALTH
202 #define	V_ipstealth		VNET(ipstealth)
203 #endif
204 #define	V_ip_rsvpd		VNET(ip_rsvpd)
205 #define	V_ip_mrouter		VNET(ip_mrouter)
206 #define	V_rsvp_on		VNET(rsvp_on)
207 #define	V_drop_redirect		VNET(drop_redirect)
208 
209 void	inp_freemoptions(struct ip_moptions *);
210 int	inp_getmoptions(struct inpcb *, struct sockopt *);
211 int	inp_setmoptions(struct inpcb *, struct sockopt *);
212 
213 int	ip_ctloutput(struct socket *, struct sockopt *sopt);
214 void	ip_drain(void);
215 int	ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
216 	    u_long if_hwassist_flags);
217 void	ip_forward(struct mbuf *m, int srcrt);
218 void	ip_init(void);
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 void	ip_savecontrol(struct inpcb *, struct mbuf **, struct ip *,
230 	    struct mbuf *);
231 void	ip_slowtimo(void);
232 void	ip_fillid(struct ip *);
233 int	rip_ctloutput(struct socket *, struct sockopt *);
234 void	rip_ctlinput(int, struct sockaddr *, void *);
235 void	rip_init(void);
236 int	rip_input(struct mbuf **, int *, int);
237 int	rip_output(struct mbuf *, struct socket *, ...);
238 int	ipip_input(struct mbuf **, int *, int);
239 int	rsvp_input(struct mbuf **, int *, int);
240 int	ip_rsvp_init(struct socket *);
241 int	ip_rsvp_done(void);
242 extern int	(*ip_rsvp_vif)(struct socket *, struct sockopt *);
243 extern void	(*ip_rsvp_force_done)(struct socket *);
244 extern int	(*rsvp_input_p)(struct mbuf **, int *, int);
245 
246 VNET_DECLARE(struct pfil_head *, inet_pfil_head);
247 #define	V_inet_pfil_head	VNET(inet_pfil_head)
248 #define	PFIL_INET_NAME		"inet"
249 
250 VNET_DECLARE(struct pfil_head *, inet_local_pfil_head);
251 #define	V_inet_local_pfil_head	VNET(inet_local_pfil_head)
252 #define	PFIL_INET_LOCAL_NAME	"inet-local"
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,	/* pipe=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, bool incoming);
302 /* ng_ipfw hooks -- XXX make it the same as divert and dummynet */
303 extern int	(*ng_ipfw_input_p)(struct mbuf **, struct ip_fw_args *, bool);
304 extern int	(*ip_dn_ctl_ptr)(struct sockopt *);
305 extern int	(*ip_dn_io_ptr)(struct mbuf **, struct ip_fw_args *);
306 #endif /* _KERNEL */
307 
308 #endif /* !_NETINET_IP_VAR_H_ */
309