ip_ipsp.h revision 1.39 
1/*	$OpenBSD: ip_ipsp.h,v 1.39 1999/07/15 14:15:41 niklas Exp $	*/
2
3/*
4 * The authors of this code are John Ioannidis (ji@tla.org),
5 * Angelos D. Keromytis (kermit@csd.uch.gr),
6 * Niels Provos (provos@physnet.uni-hamburg.de) and
7 * Niklas Hallqvist (niklas@appli.se).
8 *
9 * This code was written by John Ioannidis for BSD/OS in Athens, Greece,
10 * in November 1995.
11 *
12 * Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
13 * by Angelos D. Keromytis.
14 *
15 * Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
16 * and Niels Provos.
17 *
18 * Additional features in 1999 by Angelos D. Keromytis and Niklas Hallqvist.
19 *
20 * Copyright (c) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
21 * Angelos D. Keromytis and Niels Provos.
22 * Copyright (c) 1999 Niklas Hallqvist.
23 *
24 * Permission to use, copy, and modify this software without fee
25 * is hereby granted, provided that this entire notice is included in
26 * all copies of any software which is or includes a copy or
27 * modification of this software.
28 * You may use this code under the GNU public license if you so wish. Please
29 * contribute changes back to the authors under this freer than GPL license
30 * so that we may further the use of strong encryption without limitations to
31 * all.
32 *
33 * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
34 * IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
35 * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
36 * MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
37 * PURPOSE.
38 */
39
40#ifndef _NETINET_IPSP_H_
41#define _NETINET_IPSP_H_
42
43/*
44 * IPSP global definitions.
45 */
46
47#include <sys/types.h>
48#include <sys/queue.h>
49#include <netinet/in.h>
50#include <sys/md5k.h>
51#include <netinet/ip_sha1.h>
52#include <netinet/ip_rmd160.h>
53#include <netinet/ip_blf.h>
54#include <netinet/ip_cast.h>
55#include <netinet/ip_skipjack.h>
56
57union sockaddr_union
58{
59    struct sockaddr     sa;
60    struct sockaddr_in  sin;
61    struct sockaddr_in6 sin6;
62};
63
64/* HMAC key sizes */
65#define MD5HMAC96_KEYSIZE       16
66#define SHA1HMAC96_KEYSIZE      20
67#define RIPEMD160HMAC96_KEYSIZE 20
68
69/* IV lengths */
70#define ESP_DES_IVS		8
71#define ESP_3DES_IVS		8
72#define ESP_BLF_IVS             8
73#define ESP_CAST_IVS            8
74#define ESP_SKIPJACK_IVS	8
75#define ESP_MAX_IVS		8       /* Keep updated */
76
77/* Block sizes -- it is assumed that they're powers of 2 */
78#define ESP_DES_BLKS		8
79#define ESP_3DES_BLKS		8
80#define ESP_BLF_BLKS            8
81#define ESP_CAST_BLKS           8
82#define ESP_SKIPJACK_BLKS	8
83#define ESP_MAX_BLKS            8       /* Keep updated */
84
85#define HMAC_BLOCK_LEN		64
86
87#define AH_HMAC_HASHLEN		12	/* 96 bits of authenticator */
88#define AH_HMAC_RPLENGTH        4	/* 32 bits of replay counter */
89#define AH_HMAC_INITIAL_RPL	1	/* Replay counter initial value */
90
91/* HMAC definitions */
92#define HMAC_IPAD_VAL           0x36
93#define HMAC_OPAD_VAL           0x5C
94#define HMAC_BLOCK_LEN          64
95
96/* Authenticator lengths */
97#define AH_MD5_ALEN		16
98#define AH_SHA1_ALEN		20
99#define AH_RMD160_ALEN		20
100#define AH_ALEN_MAX		20 	/* Keep updated */
101
102/* Reserved SPI numbers */
103#define SPI_LOCAL_USE		0
104#define SPI_RESERVED_MIN	1
105#define SPI_RESERVED_MAX	255
106
107struct sockaddr_encap
108{
109    u_int8_t	sen_len;		/* length */
110    u_int8_t	sen_family;		/* PF_KEY */
111    u_int16_t	sen_type;		/* see SENT_* */
112    union
113    {
114	u_int8_t	Data[16];	/* other stuff mapped here */
115
116	struct				/* SENT_IP4 */
117	{
118	    struct in_addr Src;
119	    struct in_addr Dst;
120	    u_int16_t Sport;
121	    u_int16_t Dport;
122	    u_int8_t Proto;
123	    u_int8_t Filler[3];
124	} Sip4;
125
126	struct				/* SENT_IPSP */
127	{
128	    struct in_addr Dst;
129	    u_int32_t Spi;
130	    u_int8_t Sproto;
131	    u_int8_t Filler[7];
132	} Sipsp;
133    } Sen;
134};
135
136#define sen_data	Sen.Data
137#define sen_ip_src	Sen.Sip4.Src
138#define sen_ip_dst	Sen.Sip4.Dst
139#define sen_proto	Sen.Sip4.Proto
140#define sen_sport	Sen.Sip4.Sport
141#define sen_dport	Sen.Sip4.Dport
142#define sen_ipsp_dst	Sen.Sipsp.Dst
143#define sen_ipsp_spi	Sen.Sipsp.Spi
144#define sen_ipsp_sproto	Sen.Sipsp.Sproto
145
146/*
147 * The "type" is really part of the address as far as the routing
148 * system is concerned. By using only one bit in the type field
149 * for each type, we sort-of make sure that different types of
150 * encapsulation addresses won't be matched against the wrong type.
151 *
152 */
153
154#define SENT_IP4	0x0001		/* data is two struct in_addr */
155#define SENT_IPSP	0x0002		/* data as in IP4 plus SPI */
156
157/*
158 * SENT_HDRLEN is the length of the "header"
159 * SENT_*_LEN are the lengths of various forms of sen_data
160 * SENT_*_OFF are the offsets in the sen_data array of various fields
161 */
162
163#define SENT_HDRLEN	(2 * sizeof(u_int8_t) + sizeof(u_int16_t))
164
165#define SENT_IP4_SRCOFF	(0)
166#define SENT_IP4_DSTOFF (sizeof (struct in_addr))
167
168#define SENT_IP4_LEN	20
169#define SENT_IPSP_LEN	20
170
171#define NOTIFY_SOFT_EXPIRE      0       /* Soft expiration of SA */
172#define NOTIFY_HARD_EXPIRE      1       /* Hard expiration of SA */
173#define NOTIFY_REQUEST_SA       2       /* Establish an SA */
174
175#define NOTIFY_SATYPE_CONF      1       /* SA should do encryption */
176#define NOTIFY_SATYPE_AUTH      2       /* SA should do authentication */
177#define NOTIFY_SATYPE_TUNNEL    4       /* SA should use tunneling */
178
179/*
180 * For encapsulation routes are possible not only for the destination
181 * address but also for the protocol, source and destination ports
182 * if available
183 */
184
185struct route_enc {
186    struct rtentry *re_rt;
187    struct sockaddr_encap re_dst;
188};
189
190struct flow
191{
192    struct flow          *flow_next;	/* Next in flow chain */
193    struct flow          *flow_prev;	/* Previous in flow chain */
194    struct tdb           *flow_sa;	/* Pointer to the SA */
195    union sockaddr_union  flow_src;   	/* Source address */
196    union sockaddr_union  flow_srcmask; /* Source netmask */
197    union sockaddr_union  flow_dst;	/* Destination address */
198    union sockaddr_union  flow_dstmask;	/* Destination netmask */
199    u_int8_t	          flow_proto;	/* Transport protocol, if applicable */
200    u_int8_t	          foo[3];	/* Alignment */
201};
202
203struct tdb				/* tunnel descriptor block */
204{
205    struct tdb	     *tdb_hnext;  	/* Next in hash chain */
206    struct tdb	     *tdb_onext;        /* Next in output */
207    struct tdb	     *tdb_inext;        /* Previous in output */
208
209    struct xformsw   *tdb_xform;	/* Transformation to use */
210    struct enc_xform *tdb_encalgxform;  /* Encryption algorithm xform */
211    struct auth_hash *tdb_authalgxform; /* Authentication algorithm xform */
212
213#define TDBF_UNIQUE	      0x00001	/* This should not be used by others */
214#define TDBF_TIMER            0x00002	/* Absolute expiration timer in use */
215#define TDBF_BYTES            0x00004	/* Check the byte counters */
216#define TDBF_ALLOCATIONS      0x00008	/* Check the flows counters */
217#define TDBF_INVALID          0x00010	/* This SPI is not valid yet/anymore */
218#define TDBF_FIRSTUSE         0x00020	/* Expire after first use */
219#define TDBF_HALFIV           0x00040   /* Use half-length IV (ESP old only) */
220#define TDBF_SOFT_TIMER       0x00080	/* Soft expiration */
221#define TDBF_SOFT_BYTES       0x00100	/* Soft expiration */
222#define TDBF_SOFT_ALLOCATIONS 0x00200	/* Soft expiration */
223#define TDBF_SOFT_FIRSTUSE    0x00400	/* Soft expiration */
224#define TDBF_PFS              0x00800	/* Ask for PFS from Key Mgmt. */
225#define TDBF_TUNNELING        0x01000	/* Force IP-IP encapsulation */
226    u_int32_t	      tdb_flags;  	/* Flags related to this TDB */
227
228    TAILQ_ENTRY(tdb)  tdb_expnext;	/* Expiration cluster list link */
229    TAILQ_ENTRY(tdb)  tdb_explink;	/* Expiration ordered list link */
230
231    u_int32_t         tdb_exp_allocations;  /* Expire after so many flows */
232    u_int32_t         tdb_soft_allocations; /* Expiration warning */
233    u_int32_t         tdb_cur_allocations;  /* Total number of allocations */
234
235    u_int64_t         tdb_exp_bytes;    /* Expire after so many bytes passed */
236    u_int64_t         tdb_soft_bytes;	/* Expiration warning */
237    u_int64_t         tdb_cur_bytes;	/* Current count of bytes */
238
239    u_int64_t         tdb_exp_timeout;	/* When does the SPI expire */
240    u_int64_t         tdb_soft_timeout;	/* Send a soft-expire warning */
241    u_int64_t         tdb_established;	/* When was the SPI established */
242    u_int64_t	      tdb_timeout;	/* Next absolute expiration time.  */
243
244    u_int64_t	      tdb_first_use;	  /* When was it first used */
245    u_int64_t         tdb_soft_first_use; /* Soft warning */
246    u_int64_t         tdb_exp_first_use;  /* Expire if tdb_first_use +
247					   * tdb_exp_first_use <= curtime */
248
249    u_int32_t	      tdb_spi;    	/* SPI */
250    u_int16_t         tdb_amxkeylen;    /* AH-old only */
251    u_int16_t         tdb_ivlen;        /* IV length */
252    u_int8_t	      tdb_sproto;	/* IPsec protocol */
253    u_int8_t          tdb_wnd;          /* Replay window */
254    u_int16_t         tdb_FILLER;       /* Padding */
255
256    union sockaddr_union tdb_dst;	/* Destination address for this SA */
257    union sockaddr_union tdb_src;	/* Source address for this SA */
258    union sockaddr_union tdb_proxy;
259
260    u_int8_t         *tdb_key;          /* Key material (schedules) */
261    u_int8_t         *tdb_ictx;         /* Authentication contexts */
262    u_int8_t         *tdb_octx;
263    u_int8_t         *tdb_srcid;        /* Source ID for this SA */
264    u_int8_t         *tdb_dstid;        /* Destination ID for this SA */
265    u_int8_t         *tdb_amxkey;       /* AH-old only */
266
267    union
268    {
269	u_int8_t  Iv[ESP_3DES_IVS];     /* That's enough space */
270	u_int32_t Ivl;        	        /* Make sure this is 4 bytes */
271	u_int64_t Ivq; 		        /* Make sure this is 8 bytes! */
272    }IV;
273#define tdb_iv  IV.Iv
274#define tdb_ivl IV.Ivl
275#define tdb_ivq IV.Ivq
276
277    u_int32_t         tdb_rpl;	        /* Replay counter */
278    u_int32_t         tdb_bitmap;       /* Used for replay sliding window */
279    u_int32_t         tdb_initial;	/* Initial replay value */
280
281    u_int32_t         tdb_epoch;	/* Used by the kernfs interface */
282    u_int16_t         tdb_srcid_len;
283    u_int16_t         tdb_dstid_len;
284    u_int16_t         tdb_srcid_type;
285    u_int16_t         tdb_dstid_type;
286
287    struct flow	     *tdb_flow; 	/* Which flows use this SA */
288
289    struct tdb       *tdb_bind_out;	/* Outgoing SA to use */
290    TAILQ_HEAD(tdb_bind_head, tdb) tdb_bind_in;
291    TAILQ_ENTRY(tdb)  tdb_bind_in_next;	/* Refering Incoming SAs */
292    TAILQ_HEAD(tdb_inp_head, inpcb) tdb_inp;
293};
294
295union authctx_old {
296    MD5_CTX md5ctx;
297    SHA1_CTX sha1ctx;
298};
299
300union authctx {
301    MD5_CTX md5ctx;
302    SHA1_CTX sha1ctx;
303    RMD160_CTX rmd160ctx;
304};
305
306struct tdb_ident {
307    u_int32_t spi;
308    union sockaddr_union dst;
309    u_int8_t proto;
310};
311
312struct auth_hash {
313    int type;
314    char *name;
315    u_int16_t keysize;
316    u_int16_t hashsize;
317    u_int16_t ctxsize;
318    void (*Init)(void *);
319    void (*Update)(void *, u_int8_t *, u_int16_t);
320    void (*Final)(u_int8_t *, void *);
321};
322
323struct enc_xform {
324    int type;
325    char *name;
326    u_int16_t blocksize, ivsize;
327    u_int16_t minkey, maxkey;
328    u_int32_t ivmask;           /* Or all possible modes, zero iv = 1 */
329    void (*encrypt)(struct tdb *, u_int8_t *);
330    void (*decrypt)(struct tdb *, u_int8_t *);
331    void (*setkey)(u_int8_t **, u_int8_t *, int len);
332    void (*zerokey)(u_int8_t **);
333};
334
335struct ipsecinit
336{
337    u_int8_t       *ii_enckey;
338    u_int8_t       *ii_authkey;
339    u_int16_t       ii_enckeylen;
340    u_int16_t       ii_authkeylen;
341    u_int8_t        ii_encalg;
342    u_int8_t        ii_authalg;
343};
344
345struct xformsw
346{
347    u_short		xf_type;	/* Unique ID of xform */
348    u_short		xf_flags;	/* flags (see below) */
349    char		*xf_name;	/* human-readable name */
350    int		(*xf_attach)(void);	/* called at config time */
351    int		(*xf_init)(struct tdb *, struct xformsw *, struct ipsecinit *);
352    int		(*xf_zeroize)(struct tdb *); /* termination */
353    struct mbuf 	*(*xf_input)(struct mbuf *, struct tdb *); /* input */
354    int		(*xf_output)(struct mbuf *, struct sockaddr_encap *,
355			     struct tdb *, struct mbuf **);        /* output */
356};
357
358/* xform IDs */
359#define XF_IP4		1	/* IP inside IP */
360#define XF_OLD_AH	2	/* RFCs 1828 & 1852 */
361#define XF_OLD_ESP	3	/* RFCs 1829 & 1851 */
362#define XF_NEW_AH	4	/* AH HMAC 96bits */
363#define XF_NEW_ESP	5	/* ESP + auth 96bits + replay counter */
364#define XF_TCPSIGNATURE	6	/* TCP MD5 Signature option, RFC 2358 */
365
366/* xform attributes */
367#define XFT_AUTH	0x0001
368#define XFT_CONF	0x0100
369
370#define IPSEC_ZEROES_SIZE	64
371#define IPSEC_KERNFS_BUFSIZE    4096
372
373#if BYTE_ORDER == LITTLE_ENDIAN
374static __inline u_int64_t
375htonq(u_int64_t q)
376{
377    register u_int32_t u, l;
378    u = q >> 32;
379    l = (u_int32_t) q;
380
381    return htonl(u) | ((u_int64_t)htonl(l) << 32);
382}
383
384#define ntohq(_x) htonq(_x)
385
386#elif BYTE_ORDER == BIG_ENDIAN
387
388#define htonq(_x) (_x)
389#define ntohq(_x) htonq(_x)
390
391#else
392#error  "Please fix <machine/endian.h>"
393#endif
394
395#ifdef _KERNEL
396
397/*
398 * Protects all tdb lists.
399 * Must at least be splsoftclock.
400 */
401#define spltdb	splsoftclock
402
403extern int encdebug;
404extern int ipsec_in_use;
405extern u_int8_t hmac_ipad_buffer[64];
406extern u_int8_t hmac_opad_buffer[64];
407
408extern TAILQ_HEAD(expclusterlist_head, tdb) expclusterlist;
409extern TAILQ_HEAD(explist_head, tdb) explist;
410extern struct xformsw xformsw[], *xformswNXFORMSW;
411
412/* Check if a given tdb has encryption, authentication and/or tunneling */
413#define TDB_ATTRIB(x) (((x)->tdb_encalgxform ? NOTIFY_SATYPE_CONF : 0)| \
414		       ((x)->tdb_authalgxform ? NOTIFY_SATYPE_AUTH : 0))
415
416/* Traverse spi chain and get attributes */
417
418#define SPI_CHAIN_ATTRIB(have, TDB_DIR, TDBP) do {\
419	int s = spltdb(); \
420	struct tdb *tmptdb = (TDBP); \
421	\
422	(have) = 0; \
423	while (tmptdb && tmptdb->tdb_xform) { \
424	        if (tmptdb == NULL || tmptdb->tdb_flags & TDBF_INVALID) \
425	                break; \
426                (have) |= TDB_ATTRIB(tmptdb); \
427                tmptdb = tmptdb->TDB_DIR; \
428        } \
429	splx(s); \
430} while (0)
431
432/* Misc. */
433extern char *inet_ntoa4(struct in_addr);
434extern char *ipsp_address(union sockaddr_union);
435
436/* TDB management routines */
437extern void tdb_add_inp(struct tdb *tdb, struct inpcb *inp);
438extern u_int32_t reserve_spi(u_int32_t, u_int32_t, union sockaddr_union *,
439			     union sockaddr_union *, u_int8_t, int *);
440extern struct tdb *gettdb(u_int32_t, union sockaddr_union *, u_int8_t);
441extern void puttdb(struct tdb *);
442extern void tdb_delete(struct tdb *, int, int);
443extern int tdb_init (struct tdb *, u_int16_t, struct ipsecinit *);
444extern void tdb_expiration(struct tdb *, int);
445/* Flag values for the last argument of tdb_expiration().  */
446#define TDBEXP_EARLY	1	/* The tdb is likely to end up early.  */
447#define TDBEXP_TIMEOUT	2	/* Maintain expiration timeout.  */
448extern void handle_expirations(void *);
449
450/* Flow management routines */
451extern struct flow *get_flow(void);
452extern void put_flow(struct flow *, struct tdb *);
453extern void delete_flow(struct flow *, struct tdb *);
454extern struct flow *find_flow(union sockaddr_union *, union sockaddr_union *,
455			      union sockaddr_union *, union sockaddr_union *,
456			      u_int8_t, struct tdb *);
457extern struct flow *find_global_flow(union sockaddr_union *,
458				     union sockaddr_union *,
459				     union sockaddr_union *,
460				     union sockaddr_union *, u_int8_t);
461
462/* XF_IP4 */
463extern int ipe4_attach(void);
464extern int ipe4_init(struct tdb *, struct xformsw *, struct ipsecinit *);
465extern int ipe4_zeroize(struct tdb *);
466extern int ipe4_output(struct mbuf *, struct sockaddr_encap *, struct tdb *,
467		       struct mbuf **);
468extern void ipe4_input __P((struct mbuf *, ...));
469extern void ip4_input __P((struct mbuf *, ...));
470
471/* XF_OLD_AH */
472extern int ah_old_attach(void);
473extern int ah_old_init(struct tdb *, struct xformsw *, struct ipsecinit *);
474extern int ah_old_zeroize(struct tdb *);
475extern int ah_old_output(struct mbuf *, struct sockaddr_encap *, struct tdb *,
476			 struct mbuf **);
477extern struct mbuf *ah_old_input(struct mbuf *, struct tdb *);
478
479/* XF_NEW_AH */
480extern int ah_new_attach(void);
481extern int ah_new_init(struct tdb *, struct xformsw *, struct ipsecinit *);
482extern int ah_new_zeroize(struct tdb *);
483extern int ah_new_output(struct mbuf *, struct sockaddr_encap *, struct tdb *,
484			 struct mbuf **);
485extern struct mbuf *ah_new_input(struct mbuf *, struct tdb *);
486
487/* XF_OLD_ESP */
488extern int esp_old_attach(void);
489extern int esp_old_init(struct tdb *, struct xformsw *, struct ipsecinit *);
490extern int esp_old_zeroize(struct tdb *);
491extern int esp_old_output(struct mbuf *, struct sockaddr_encap *, struct tdb *,
492			  struct mbuf **);
493extern struct mbuf *esp_old_input(struct mbuf *, struct tdb *);
494
495/* XF_NEW_ESP */
496extern int esp_new_attach(void);
497extern int esp_new_init(struct tdb *, struct xformsw *, struct ipsecinit *);
498extern int esp_new_zeroize(struct tdb *);
499extern int esp_new_output(struct mbuf *, struct sockaddr_encap *, struct tdb *,
500			  struct mbuf **);
501extern struct mbuf *esp_new_input(struct mbuf *, struct tdb *);
502
503/* XF_TCPSIGNATURE */
504extern int tcp_signature_tdb_attach __P((void));
505extern int tcp_signature_tdb_init __P((struct tdb *, struct xformsw *,
506				       struct ipsecinit *));
507extern int tcp_signature_tdb_zeroize __P((struct tdb *));
508extern struct mbuf *tcp_signature_tdb_input __P((struct mbuf *, struct tdb *));
509extern int tcp_signature_tdb_output __P((struct mbuf *,
510					 struct sockaddr_encap *, struct tdb *,
511					 struct mbuf **));
512
513/* Padding */
514extern caddr_t m_pad(struct mbuf *, int, int);
515
516/* Replay window */
517extern int checkreplaywindow32(u_int32_t, u_int32_t, u_int32_t *, u_int32_t,
518                               u_int32_t *);
519
520extern unsigned char ipseczeroes[];
521#endif /* _KERNEL */
522#endif /* _NETINET_IPSP_H_ */
523