1/*	$NetBSD: ipsec.h,v 1.93 2022/10/28 05:23:09 ozaki-r Exp $	*/
  2/*	$FreeBSD: ipsec.h,v 1.2.4.2 2004/02/14 22:23:23 bms Exp $	*/
  3/*	$KAME: ipsec.h,v 1.53 2001/11/20 08:32:38 itojun Exp $	*/
  4
  5/*
  6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  7 * All rights reserved.
  8 *
  9 * Redistribution and use in source and binary forms, with or without
 10 * modification, are permitted provided that the following conditions
 11 * are met:
 12 * 1. Redistributions of source code must retain the above copyright
 13 *    notice, this list of conditions and the following disclaimer.
 14 * 2. Redistributions in binary form must reproduce the above copyright
 15 *    notice, this list of conditions and the following disclaimer in the
 16 *    documentation and/or other materials provided with the distribution.
 17 * 3. Neither the name of the project nor the names of its contributors
 18 *    may be used to endorse or promote products derived from this software
 19 *    without specific prior written permission.
 20 *
 21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 31 * SUCH DAMAGE.
 32 */
 33
 34#ifndef _NETIPSEC_IPSEC_H_
 35#define _NETIPSEC_IPSEC_H_
 36
 37#if defined(_KERNEL_OPT)
 38#include "opt_inet.h"
 39#include "opt_ipsec.h"
 40#endif
 41
 42#include <net/pfkeyv2.h>
 43
 44#ifdef _KERNEL
 45#include <sys/socketvar.h>
 46#include <sys/localcount.h>
 47
 48#include <netinet/in_pcb.h>
 49#include <netipsec/keydb.h>
 50
 51/*
 52 * Security Policy Index
 53 * Ensure that both address families in the "src" and "dst" are same.
 54 * When the value of the ul_proto is ICMPv6, the port field in "src"
 55 * specifies ICMPv6 type, and the port field in "dst" specifies ICMPv6 code.
 56 */
 57struct secpolicyindex {
 58	u_int8_t dir;			/* direction of packet flow, see blow */
 59	union sockaddr_union src;	/* IP src address for SP */
 60	union sockaddr_union dst;	/* IP dst address for SP */
 61	u_int8_t prefs;			/* prefix length in bits for src */
 62	u_int8_t prefd;			/* prefix length in bits for dst */
 63	u_int16_t ul_proto;		/* upper layer Protocol */
 64};
 65
 66/* Security Policy Data Base */
 67struct secpolicy {
 68	struct pslist_entry pslist_entry;
 69
 70	struct localcount localcount;	/* reference count */
 71	struct secpolicyindex spidx;	/* selector */
 72	u_int32_t id;			/* It's unique number on the system. */
 73	u_int state;			/* 0: dead, others: alive */
 74#define IPSEC_SPSTATE_DEAD	0
 75#define IPSEC_SPSTATE_ALIVE	1
 76
 77	u_int origin;			/* who generate this SP. */
 78#define IPSEC_SPORIGIN_USER	0
 79#define IPSEC_SPORIGIN_KERNEL	1
 80
 81	u_int policy;		/* DISCARD, NONE or IPSEC, see keyv2.h */
 82	struct ipsecrequest *req;
 83				/* pointer to the ipsec request tree, */
 84				/* if policy == IPSEC else this value == NULL.*/
 85
 86	/*
 87	 * lifetime handler.
 88	 * the policy can be used without limitiation if both lifetime and
 89	 * validtime are zero.
 90	 * "lifetime" is passed by sadb_lifetime.sadb_lifetime_addtime.
 91	 * "validtime" is passed by sadb_lifetime.sadb_lifetime_usetime.
 92	 */
 93	time_t created;		/* time created the policy */
 94	time_t lastused;	/* updated every when kernel sends a packet */
 95	time_t lifetime;	/* duration of the lifetime of this policy */
 96	time_t validtime;	/* duration this policy is valid without use */
 97};
 98
 99/* Request for IPsec */
100struct ipsecrequest {
101	struct ipsecrequest *next;
102				/* pointer to next structure */
103				/* If NULL, it means the end of chain. */
104	struct secasindex saidx;/* hint for search proper SA */
105				/* if __ss_len == 0 then no address specified.*/
106	u_int level;		/* IPsec level defined below. */
107
108	struct secpolicy *sp;	/* back pointer to SP */
109};
110
111/* security policy in PCB */
112struct inpcbpolicy {
113	struct secpolicy *sp_in;
114	struct secpolicy *sp_out;
115	int priv;			/* privileged socket ? */
116
117	/* cached policy */
118	struct {
119		struct secpolicy *cachesp;
120		struct secpolicyindex cacheidx;
121		int cachehint;		/* processing requirement hint: */
122#define	IPSEC_PCBHINT_UNKNOWN	0	/* Unknown */
123#define	IPSEC_PCBHINT_YES	1	/* IPsec processing is required */
124#define	IPSEC_PCBHINT_NO	2	/* IPsec processing not required */
125		u_int cachegen;		/* spdgen when cache filled */
126	} sp_cache[3];			/* XXX 3 == IPSEC_DIR_MAX */
127	int sp_cacheflags;
128#define	IPSEC_PCBSP_CONNECTED	1
129	struct inpcb *sp_inp;		/* back pointer */
130};
131
132extern u_int ipsec_spdgen;
133
134static __inline bool
135ipsec_pcb_skip_ipsec(struct inpcbpolicy *pcbsp, int dir)
136{
137
138	KASSERT(inp_locked(pcbsp->sp_inp));
139
140	return pcbsp->sp_cache[(dir)].cachehint == IPSEC_PCBHINT_NO &&
141	    pcbsp->sp_cache[(dir)].cachegen == ipsec_spdgen;
142}
143
144/* SP acquiring list table. */
145struct secspacq {
146	LIST_ENTRY(secspacq) chain;
147
148	struct secpolicyindex spidx;
149
150	time_t created;		/* for lifetime */
151	int count;		/* for lifetime */
152	/* XXX: here is mbuf place holder to be sent ? */
153};
154#endif /* _KERNEL */
155
156/* buffer size for formatted output of ipsec address (addr + '%' + scope_id?) */
157#define	IPSEC_ADDRSTRLEN	(INET6_ADDRSTRLEN + 11)
158/* buffer size for ipsec_logsastr() */
159#define	IPSEC_LOGSASTRLEN	192
160
161/* according to IANA assignment, port 0x0000 and proto 0xff are reserved. */
162#define IPSEC_PORT_ANY		0
163#define IPSEC_ULPROTO_ANY	255
164#define IPSEC_PROTO_ANY		255
165
166/* mode of security protocol */
167/* NOTE: DON'T use IPSEC_MODE_ANY at SPD.  It's only use in SAD */
168#define	IPSEC_MODE_ANY		0	/* i.e. wildcard. */
169#define	IPSEC_MODE_TRANSPORT	1
170#define	IPSEC_MODE_TUNNEL	2
171#define	IPSEC_MODE_TCPMD5	3	/* TCP MD5 mode */
172
173/*
174 * Direction of security policy.
175 * NOTE: Since INVALID is used just as flag.
176 * The other are used for loop counter too.
177 */
178#define IPSEC_DIR_ANY		0
179#define IPSEC_DIR_INBOUND	1
180#define IPSEC_DIR_OUTBOUND	2
181#define IPSEC_DIR_MAX		3
182#define IPSEC_DIR_INVALID	4
183
184#define IPSEC_DIR_IS_VALID(dir)		((dir) >= 0 && (dir) <= IPSEC_DIR_MAX)
185#define IPSEC_DIR_IS_INOROUT(dir)	((dir) == IPSEC_DIR_INBOUND || \
186					 (dir) == IPSEC_DIR_OUTBOUND)
187
188/* Policy level */
189/*
190 * IPSEC, ENTRUST and BYPASS are allowed for setsockopt() in PCB,
191 * DISCARD, IPSEC and NONE are allowed for setkey() in SPD.
192 * DISCARD and NONE are allowed for system default.
193 */
194#define IPSEC_POLICY_DISCARD	0	/* discarding packet */
195#define IPSEC_POLICY_NONE	1	/* through IPsec engine */
196#define IPSEC_POLICY_IPSEC	2	/* do IPsec */
197#define IPSEC_POLICY_ENTRUST	3	/* consulting SPD if present. */
198#define IPSEC_POLICY_BYPASS	4	/* only for privileged socket. */
199
200/* Security protocol level */
201#define	IPSEC_LEVEL_DEFAULT	0	/* reference to system default */
202#define	IPSEC_LEVEL_USE		1	/* use SA if present. */
203#define	IPSEC_LEVEL_REQUIRE	2	/* require SA. */
204#define	IPSEC_LEVEL_UNIQUE	3	/* unique SA. */
205
206#define IPSEC_MANUAL_REQID_MAX	0x3fff
207				/*
208				 * if security policy level == unique, this id
209				 * indicate to a relative SA for use, else is
210				 * zero.
211				 * 1 - 0x3fff are reserved for manual keying.
212				 * 0 are reserved for above reason.  Others is
213				 * for kernel use.
214				 * Note that this id doesn't identify SA
215				 * by only itself.
216				 */
217#define IPSEC_REPLAYWSIZE  32
218
219#ifdef _KERNEL
220
221extern int ipsec_debug;
222#ifdef IPSEC_DEBUG
223extern int ipsec_replay;
224extern int ipsec_integrity;
225#endif
226
227extern struct secpolicy ip4_def_policy;
228extern int ip4_esp_trans_deflev;
229extern int ip4_esp_net_deflev;
230extern int ip4_ah_trans_deflev;
231extern int ip4_ah_net_deflev;
232extern int ip4_ah_cleartos;
233extern int ip4_ah_offsetmask;
234extern int ip4_ipsec_dfbit;
235extern int ip4_ipsec_ecn;
236extern int crypto_support;
237
238#include <sys/syslog.h>
239
240#define	DPRINTF(fmt, args...) 						\
241	do {								\
242		if (ipsec_debug)					\
243			log(LOG_DEBUG, "%s: " fmt, __func__, ##args);	\
244	} while (/*CONSTCOND*/0)
245
246#define IPSECLOG(level, fmt, args...) 					\
247	do {								\
248		if (ipsec_debug)					\
249			log(level, "%s: " fmt, __func__, ##args);	\
250	} while (/*CONSTCOND*/0)
251
252#define ipsec_indone(m)	\
253	((m->m_flags & M_AUTHIPHDR) || (m->m_flags & M_DECRYPTED))
254#define ipsec_outdone(m) \
255	(m_tag_find((m), PACKET_TAG_IPSEC_OUT_DONE) != NULL)
256
257static __inline bool
258ipsec_skip_pfil(struct mbuf *m)
259{
260	bool rv;
261
262	if (ipsec_indone(m) &&
263	    ((m->m_pkthdr.pkthdr_flags & PKTHDR_FLAG_IPSEC_SKIP_PFIL) != 0)) {
264		m->m_pkthdr.pkthdr_flags &= ~PKTHDR_FLAG_IPSEC_SKIP_PFIL;
265		rv = true;
266	} else {
267		rv = false;
268	}
269
270	return rv;
271}
272
273void ipsec_pcbconn(struct inpcbpolicy *);
274void ipsec_pcbdisconn(struct inpcbpolicy *);
275void ipsec_invalpcbcacheall(void);
276
277struct inpcb;
278int ipsec4_output(struct mbuf *, struct inpcb *, int, u_long *, bool *, bool *, bool *);
279
280int ipsec_ip_input_checkpolicy(struct mbuf *, bool);
281void ipsec_mtu(struct mbuf *, int *);
282#ifdef INET6
283void ipsec6_udp_cksum(struct mbuf *);
284#endif
285
286struct inpcb;
287int ipsec_init_pcbpolicy(struct socket *so, struct inpcbpolicy **);
288int ipsec_copy_policy(const struct inpcbpolicy *, struct inpcbpolicy *);
289u_int ipsec_get_reqlevel(const struct ipsecrequest *);
290
291int ipsec_set_policy(struct inpcb *, const void *, size_t, kauth_cred_t);
292int ipsec_get_policy(struct inpcb *, const void *, size_t, struct mbuf **);
293int ipsec_delete_pcbpolicy(struct inpcb *);
294int ipsec_in_reject(struct mbuf *, struct inpcb *);
295
296struct secasvar *ipsec_lookup_sa(const struct ipsecrequest *,
297    const struct mbuf *);
298
299struct secas;
300struct tcpcb;
301int ipsec_chkreplay(u_int32_t, const struct secasvar *);
302int ipsec_updatereplay(u_int32_t, const struct secasvar *);
303
304size_t ipsec_hdrsiz(struct mbuf *, u_int, struct inpcb *);
305size_t ipsec4_hdrsiz_tcp(struct tcpcb *);
306
307union sockaddr_union;
308const char *ipsec_address(const union sockaddr_union* sa, char *, size_t);
309const char *ipsec_logsastr(const struct secasvar *, char *, size_t);
310
311/* NetBSD protosw ctlin entrypoint */
312void *esp4_ctlinput(int, const struct sockaddr *, void *);
313void *ah4_ctlinput(int, const struct sockaddr *, void *);
314
315void ipsec_output_init(void);
316struct m_tag;
317void ipsec4_common_input(struct mbuf *m, int, int);
318int ipsec4_common_input_cb(struct mbuf *, struct secasvar *, int, int);
319int ipsec4_process_packet(struct mbuf *, const struct ipsecrequest *, u_long *);
320int ipsec_process_done(struct mbuf *, const struct ipsecrequest *,
321    struct secasvar *, int);
322
323struct mbuf *m_clone(struct mbuf *);
324struct mbuf *m_makespace(struct mbuf *, int, int, int *);
325void *m_pad(struct mbuf *, int);
326int m_striphdr(struct mbuf *, int, int);
327
328extern int ipsec_used __read_mostly;
329extern int ipsec_enabled __read_mostly;
330
331#endif /* _KERNEL */
332
333#ifndef _KERNEL
334char *ipsec_set_policy(const char *, int);
335int ipsec_get_policylen(char *);
336char *ipsec_dump_policy(char *, const char *);
337const char *ipsec_strerror(void);
338#endif /* !_KERNEL */
339
340#ifdef _KERNEL
341/* External declarations of per-file init functions */
342void ah_attach(void);
343void esp_attach(void);
344void ipcomp_attach(void);
345void ipe4_attach(void);
346void tcpsignature_attach(void);
347
348void ipsec_attach(void);
349
350void sysctl_net_inet_ipsec_setup(struct sysctllog **);
351#ifdef INET6
352void sysctl_net_inet6_ipsec6_setup(struct sysctllog **);
353#endif
354
355#endif /* _KERNEL */
356#endif /* !_NETIPSEC_IPSEC_H_ */