xref: /freebsd/sys/netinet/ip_var.h (revision cddbc3b40812213ff00041f79174cac0be360a2a)
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  * $FreeBSD$
33  */
34 
35 #ifndef _NETINET_IP_VAR_H_
36 #define	_NETINET_IP_VAR_H_
37 
38 #include <sys/queue.h>
39 #include <sys/epoch.h>
40 
41 /*
42  * Overlay for ip header used by other protocols (tcp, udp).
43  */
44 struct ipovly {
45 	u_char	ih_x1[9];		/* (unused) */
46 	u_char	ih_pr;			/* protocol */
47 	u_short	ih_len;			/* protocol length */
48 	struct	in_addr ih_src;		/* source internet address */
49 	struct	in_addr ih_dst;		/* destination internet address */
50 };
51 
52 #ifdef _KERNEL
53 /*
54  * Ip reassembly queue structure.  Each fragment
55  * being reassembled is attached to one of these structures.
56  * They are timed out after ipq_ttl drops to 0, and may also
57  * be reclaimed if memory becomes tight.
58  */
59 struct ipq {
60 	TAILQ_ENTRY(ipq) ipq_list;	/* to other reass headers */
61 	u_char	ipq_ttl;		/* time for reass q to live */
62 	u_char	ipq_p;			/* protocol of this fragment */
63 	u_short	ipq_id;			/* sequence id for reassembly */
64 	int	ipq_maxoff;		/* total length of packet */
65 	struct mbuf *ipq_frags;		/* to ip headers of fragments */
66 	struct	in_addr ipq_src,ipq_dst;
67 	u_char	ipq_nfrags;		/* # frags in this packet */
68 	struct label *ipq_label;	/* MAC label */
69 };
70 #endif /* _KERNEL */
71 
72 /*
73  * Structure stored in mbuf in inpcb.ip_options
74  * and passed to ip_output when ip options are in use.
75  * The actual length of the options (including ipopt_dst)
76  * is in m_len.
77  */
78 #define MAX_IPOPTLEN	40
79 
80 struct ipoption {
81 	struct	in_addr ipopt_dst;	/* first-hop dst if source routed */
82 	char	ipopt_list[MAX_IPOPTLEN];	/* options proper */
83 };
84 
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 	u_short	imo_num_memberships;	/* no. memberships this socket */
97 	u_short	imo_max_memberships;	/* max memberships this socket */
98 	struct	in_multi **imo_membership;	/* group memberships */
99 	struct	in_mfilter *imo_mfilters;	/* source filters */
100 	struct	epoch_context imo_epoch_ctx;
101 };
102 
103 struct	ipstat {
104 	uint64_t ips_total;		/* total packets received */
105 	uint64_t ips_badsum;		/* checksum bad */
106 	uint64_t ips_tooshort;		/* packet too short */
107 	uint64_t ips_toosmall;		/* not enough data */
108 	uint64_t ips_badhlen;		/* ip header length < data size */
109 	uint64_t ips_badlen;		/* ip length < ip header length */
110 	uint64_t ips_fragments;		/* fragments received */
111 	uint64_t ips_fragdropped;	/* frags dropped (dups, out of space) */
112 	uint64_t ips_fragtimeout;	/* fragments timed out */
113 	uint64_t ips_forward;		/* packets forwarded */
114 	uint64_t ips_fastforward;	/* packets fast forwarded */
115 	uint64_t ips_cantforward;	/* packets rcvd for unreachable dest */
116 	uint64_t ips_redirectsent;	/* packets forwarded on same net */
117 	uint64_t ips_noproto;		/* unknown or unsupported protocol */
118 	uint64_t ips_delivered;		/* datagrams delivered to upper level*/
119 	uint64_t ips_localout;		/* total ip packets generated here */
120 	uint64_t ips_odropped;		/* lost packets due to nobufs, etc. */
121 	uint64_t ips_reassembled;	/* total packets reassembled ok */
122 	uint64_t ips_fragmented;	/* datagrams successfully fragmented */
123 	uint64_t ips_ofragments;	/* output fragments created */
124 	uint64_t ips_cantfrag;		/* don't fragment flag was set, etc. */
125 	uint64_t ips_badoptions;		/* error in option processing */
126 	uint64_t ips_noroute;		/* packets discarded due to no route */
127 	uint64_t ips_badvers;		/* ip version != 4 */
128 	uint64_t ips_rawout;		/* total raw ip packets generated */
129 	uint64_t ips_toolong;		/* ip length > max ip packet size */
130 	uint64_t ips_notmember;		/* multicasts for unregistered grps */
131 	uint64_t ips_nogif;		/* no match gif found */
132 	uint64_t ips_badaddr;		/* invalid address on header */
133 };
134 
135 #ifdef _KERNEL
136 
137 #include <sys/counter.h>
138 #include <net/vnet.h>
139 
140 VNET_PCPUSTAT_DECLARE(struct ipstat, ipstat);
141 /*
142  * In-kernel consumers can use these accessor macros directly to update
143  * stats.
144  */
145 #define	IPSTAT_ADD(name, val)	\
146     VNET_PCPUSTAT_ADD(struct ipstat, ipstat, name, (val))
147 #define	IPSTAT_SUB(name, val)	IPSTAT_ADD(name, -(val))
148 #define	IPSTAT_INC(name)	IPSTAT_ADD(name, 1)
149 #define	IPSTAT_DEC(name)	IPSTAT_SUB(name, 1)
150 
151 /*
152  * Kernel module consumers must use this accessor macro.
153  */
154 void	kmod_ipstat_inc(int statnum);
155 #define	KMOD_IPSTAT_INC(name)	\
156     kmod_ipstat_inc(offsetof(struct ipstat, name) / sizeof(uint64_t))
157 void	kmod_ipstat_dec(int statnum);
158 #define	KMOD_IPSTAT_DEC(name)	\
159     kmod_ipstat_dec(offsetof(struct ipstat, name) / sizeof(uint64_t))
160 
161 /* flags passed to ip_output as last parameter */
162 #define	IP_FORWARDING		0x1		/* most of ip header exists */
163 #define	IP_RAWOUTPUT		0x2		/* raw ip header exists */
164 #define	IP_SENDONES		0x4		/* send all-ones broadcast */
165 #define	IP_SENDTOIF		0x8		/* send on specific ifnet */
166 #define IP_ROUTETOIF		SO_DONTROUTE	/* 0x10 bypass routing tables */
167 #define IP_ALLOWBROADCAST	SO_BROADCAST	/* 0x20 can send broadcast packets */
168 #define	IP_NODEFAULTFLOWID	0x40		/* Don't set the flowid from inp */
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 #ifdef IPSTEALTH
185 VNET_DECLARE(int, ipstealth);			/* stealth forwarding */
186 #endif
187 extern u_char	ip_protox[];
188 VNET_DECLARE(struct socket *, ip_rsvpd);	/* reservation protocol daemon*/
189 VNET_DECLARE(struct socket *, ip_mrouter);	/* multicast routing daemon */
190 extern int	(*legal_vif_num)(int);
191 extern u_long	(*ip_mcast_src)(int);
192 VNET_DECLARE(int, rsvp_on);
193 VNET_DECLARE(int, drop_redirect);
194 extern struct	pr_usrreqs rip_usrreqs;
195 
196 #define	V_ip_id			VNET(ip_id)
197 #define	V_ip_defttl		VNET(ip_defttl)
198 #define	V_ipforwarding		VNET(ipforwarding)
199 #ifdef IPSTEALTH
200 #define	V_ipstealth		VNET(ipstealth)
201 #endif
202 #define	V_ip_rsvpd		VNET(ip_rsvpd)
203 #define	V_ip_mrouter		VNET(ip_mrouter)
204 #define	V_rsvp_on		VNET(rsvp_on)
205 #define	V_drop_redirect		VNET(drop_redirect)
206 
207 void	inp_freemoptions(struct ip_moptions *);
208 int	inp_getmoptions(struct inpcb *, struct sockopt *);
209 int	inp_setmoptions(struct inpcb *, struct sockopt *);
210 
211 int	ip_ctloutput(struct socket *, struct sockopt *sopt);
212 void	ip_drain(void);
213 int	ip_fragment(struct ip *ip, struct mbuf **m_frag, int mtu,
214 	    u_long if_hwassist_flags);
215 void	ip_forward(struct mbuf *m, int srcrt);
216 void	ip_init(void);
217 extern int
218 	(*ip_mforward)(struct ip *, struct ifnet *, struct mbuf *,
219 	    struct ip_moptions *);
220 int	ip_output(struct mbuf *,
221 	    struct mbuf *, struct route *, int, struct ip_moptions *,
222 	    struct inpcb *);
223 int	ipproto_register(short);
224 int	ipproto_unregister(short);
225 struct mbuf *
226 	ip_reass(struct mbuf *);
227 void	ip_savecontrol(struct inpcb *, struct mbuf **, struct ip *,
228 	    struct mbuf *);
229 void	ip_slowtimo(void);
230 void	ip_fillid(struct ip *);
231 int	rip_ctloutput(struct socket *, struct sockopt *);
232 void	rip_ctlinput(int, struct sockaddr *, void *);
233 void	rip_init(void);
234 int	rip_input(struct mbuf **, int *, int);
235 int	rip_output(struct mbuf *, struct socket *, ...);
236 int	ipip_input(struct mbuf **, int *, int);
237 int	rsvp_input(struct mbuf **, int *, int);
238 int	ip_rsvp_init(struct socket *);
239 int	ip_rsvp_done(void);
240 extern int	(*ip_rsvp_vif)(struct socket *, struct sockopt *);
241 extern void	(*ip_rsvp_force_done)(struct socket *);
242 extern int	(*rsvp_input_p)(struct mbuf **, int *, int);
243 
244 VNET_DECLARE(struct pfil_head *, inet_pfil_head);
245 #define	V_inet_pfil_head	VNET(inet_pfil_head)
246 #define	PFIL_INET_NAME		"inet"
247 
248 void	in_delayed_cksum(struct mbuf *m);
249 
250 /* Hooks for ipfw, dummynet, divert etc. Most are declared in raw_ip.c */
251 /*
252  * Reference to an ipfw or packet filter rule that can be carried
253  * outside critical sections.
254  * A rule is identified by rulenum:rule_id which is ordered.
255  * In version chain_id the rule can be found in slot 'slot', so
256  * we don't need a lookup if chain_id == chain->id.
257  *
258  * On exit from the firewall this structure refers to the rule after
259  * the matching one (slot points to the new rule; rulenum:rule_id-1
260  * is the matching rule), and additional info (e.g. info often contains
261  * the insn argument or tablearg in the low 16 bits, in host format).
262  * On entry, the structure is valid if slot>0, and refers to the starting
263  * rules. 'info' contains the reason for reinject, e.g. divert port,
264  * divert direction, and so on.
265  */
266 struct ipfw_rule_ref {
267 	uint32_t	slot;		/* slot for matching rule	*/
268 	uint32_t	rulenum;	/* matching rule number		*/
269 	uint32_t	rule_id;	/* matching rule id		*/
270 	uint32_t	chain_id;	/* ruleset id			*/
271 	uint32_t	info;		/* see below			*/
272 };
273 
274 enum {
275 	IPFW_INFO_MASK	= 0x0000ffff,
276 	IPFW_INFO_OUT	= 0x00000000,	/* outgoing, just for convenience */
277 	IPFW_INFO_IN	= 0x80000000,	/* incoming, overloads dir */
278 	IPFW_ONEPASS	= 0x40000000,	/* One-pass, do not reinject */
279 	IPFW_IS_MASK	= 0x30000000,	/* which source ? */
280 	IPFW_IS_DIVERT	= 0x20000000,
281 	IPFW_IS_DUMMYNET =0x10000000,
282 	IPFW_IS_PIPE	= 0x08000000,	/* pipe=1, queue = 0 */
283 };
284 #define MTAG_IPFW	1148380143	/* IPFW-tagged cookie */
285 #define MTAG_IPFW_RULE	1262273568	/* rule reference */
286 #define	MTAG_IPFW_CALL	1308397630	/* call stack */
287 
288 struct ip_fw_args;
289 typedef int	(*ip_fw_chk_ptr_t)(struct ip_fw_args *args);
290 typedef int	(*ip_fw_ctl_ptr_t)(struct sockopt *);
291 VNET_DECLARE(ip_fw_ctl_ptr_t, ip_fw_ctl_ptr);
292 #define	V_ip_fw_ctl_ptr		VNET(ip_fw_ctl_ptr)
293 
294 /* Divert hooks. */
295 extern void	(*ip_divert_ptr)(struct mbuf *m, bool incoming);
296 /* ng_ipfw hooks -- XXX make it the same as divert and dummynet */
297 extern int	(*ng_ipfw_input_p)(struct mbuf **, struct ip_fw_args *, bool);
298 extern int	(*ip_dn_ctl_ptr)(struct sockopt *);
299 extern int	(*ip_dn_io_ptr)(struct mbuf **, struct ip_fw_args *);
300 #endif /* _KERNEL */
301 
302 #endif /* !_NETINET_IP_VAR_H_ */
303