xref: /openbsd-src/sbin/isakmpd/exchange.h (revision f2da64fbbbf1b03f09f390ab01267c93dfd77c4c)
1 /* $OpenBSD: exchange.h,v 1.34 2015/01/16 06:39:58 deraadt Exp $	 */
2 /* $EOM: exchange.h,v 1.28 2000/09/28 12:54:28 niklas Exp $	 */
3 
4 /*
5  * Copyright (c) 1998, 1999, 2001 Niklas Hallqvist.  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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 /*
29  * This code was written under funding by Ericsson Radio Systems.
30  */
31 
32 #ifndef _EXCHANGE_H_
33 #define _EXCHANGE_H_
34 
35 #include <sys/types.h>
36 #include <sys/queue.h>
37 
38 #include "exchange_num.h"
39 #include "isakmp.h"
40 
41 /* Remove an exchange if it has not been fully negotiated in this time.  */
42 #define EXCHANGE_MAX_TIME 120
43 
44 struct crypto_xf;
45 struct certreq_aca;
46 struct doi;
47 struct event;
48 struct keystate;
49 struct message;
50 struct payload;
51 struct transport;
52 struct sa;
53 
54 struct exchange {
55 	/* Link to exchanges with the same hash value.  */
56 	LIST_ENTRY(exchange) link;
57 
58 	/* A name of the SAs this exchange will result in.  XXX non unique?  */
59 	char           *name;
60 
61 	/*
62 	 * A name of the major policy deciding offers and acceptable
63 	 * proposals.
64 	 */
65 	char           *policy;
66 
67 	/*
68 	 * A function with a polymorphic argument called after the exchange
69 	 * has been run to its end, successfully.  The 2nd argument is true
70 	 * if the finalization hook is called due to the exchange not running
71 	 * to its end normally.
72          */
73 	void            (*finalize)(struct exchange *, void *, int);
74 	void           *finalize_arg;
75 
76 	/* When several SA's are being negotiated we keep them here.  */
77 	TAILQ_HEAD(sa_head, sa) sa_list;
78 
79 	/*
80 	 * The event that will occur when it has taken too long time to try to
81 	 * run the exchange and which will trigger auto-destruction.
82          */
83 	struct event   *death;
84 
85 	/*
86 	 * Both initiator and responder cookies.
87 	 * XXX For code clarity we might split this into two fields.
88          */
89 	u_int8_t        cookies[ISAKMP_HDR_COOKIES_LEN];
90 
91 	/* The message ID signifying phase 2 exchanges.  */
92 	u_int8_t        message_id[ISAKMP_HDR_MESSAGE_ID_LEN];
93 
94 	/* The exchange type we are using.  */
95 	u_int8_t        type;
96 
97 	/* Phase is 1 for ISAKMP SA exchanges, and 2 for application ones.  */
98 	u_int8_t        phase;
99 
100 	/* The "step counter" of the exchange, starting from zero.  */
101 	u_int8_t        step;
102 
103 	/* 1 if we are the initiator, 0 if we are the responder.  */
104 	u_int8_t        initiator;
105 
106 	/* Various flags, look below for descriptions.  */
107 	u_int32_t       flags;
108 
109 	/* The DOI that is to handle DOI-specific issues for this exchange.  */
110 	struct doi     *doi;
111 
112 	/*
113 	 * A "program counter" into the script that validate message contents
114 	 * for this exchange.
115          */
116 	int16_t        *exch_pc;
117 
118 	/* The last message received, used for checking for duplicates.  */
119 	struct message *last_received;
120 
121 	/* The last message sent, to be acked when something new is received.  */
122 	struct message *last_sent;
123 
124 	/*
125 	 * If some message is queued up for sending, we want to be able to
126 	 * remove it from the queue, when the exchange is deleted.
127          */
128 	struct message *in_transit;
129 
130 	/*
131 	 * Initiator's & responder's nonces respectively, with lengths.
132 	 * XXX Should this be in the DOI-specific parts instead?
133          */
134 	u_int8_t       *nonce_i;
135 	size_t          nonce_i_len;
136 	u_int8_t       *nonce_r;
137 	size_t          nonce_r_len;
138 
139 	/*
140 	 * The ID payload contents for the initiator & responder,
141 	 * respectively.
142 	 */
143 	u_int8_t       *id_i;
144 	size_t          id_i_len;
145 	u_int8_t       *id_r;
146 	size_t          id_r_len;
147 
148 	/* Policy session identifier, where applicable.  */
149 	int             policy_id;
150 
151 	/* Crypto info needed to encrypt/decrypt packets in this exchange.  */
152 	struct crypto_xf *crypto;
153 	size_t          key_length;
154 	struct keystate *keystate;
155 
156 	/*
157 	 * Used only by KeyNote, to cache the key used to authenticate Phase
158 	 * 1
159 	 */
160 	char           *keynote_key;	/* printable format */
161 
162 	/*
163 	 * Received certificate - used to verify signatures on packet,
164 	 * stored here for later policy processing.
165          *
166 	 * The rules for the recv_* and sent_* fields are:
167 	 * - recv_cert stores the credential (if any) received from the peer;
168 	 *   the kernel may pass us one, but we ignore it. We pass it to the
169 	 *   kernel so processes can peek at it. When doing passphrase
170 	 *   authentication in Phase 1, this is empty.
171 	 * - recv_key stores the key (public or private) used by the peer
172 	 *   to authenticate. Otherwise, same properties as recv_cert except
173 	 *   that we don't tell the kernel about passphrases (so we don't
174 	 *   reveal system-wide passphrases). Processes that used passphrase
175 	 *   authentication already know the passphrase! We ignore it if/when
176 	 *   received from the kernel (meaningless).
177 	 * - sent_cert stores the credential, if any, we used to authenticate
178 	 *   with the peer. It may be passed to us by the kernel, or we may
179 	 *   have found it in our certificate storage. In either case, there's
180 	 *   no point passing it to the kernel, so we don't.
181 	 * - sent key stores the private key we used for authentication with
182 	 *   the peer (private key or passphrase). This may have been received
183 	 *   from the kernel, or may be a system-wide setting. In either case,
184 	 *   we don't pass it to the kernel, to avoid revealing such information
185 	 *   to processes (processes either already know it, or have no business
186 	 *   knowing it).
187          */
188 	int             recv_certtype, recv_keytype;
189 	void           *recv_cert;	/* Certificate received from peer,
190 					 * native format */
191 	void           *recv_key;	/* Key peer used to authenticate,
192 					 * native format */
193 
194 	/* Likewise, for certificates we use. */
195 	int             sent_certtype, sent_keytype;
196 	void           *sent_cert;	/* Certificate (to be) sent to peer,
197 					 * native format */
198 
199 	/* ACQUIRE sequence number.  */
200 	u_int32_t       seq;
201 
202 	/* XXX This is no longer necessary, it is covered by policy.  */
203 
204 	/* Acceptable authorities for cert requests.  */
205 	TAILQ_HEAD(aca_head, certreq_aca) aca_list;
206 
207 	/* DOI-specific opaque data.  */
208 	void           *data;
209 };
210 
211 /* The flag bits.  */
212 #define EXCHANGE_FLAG_I_COMMITTED	0x0001
213 #define EXCHANGE_FLAG_HE_COMMITTED	0x0002
214 #define EXCHANGE_FLAG_COMMITTED		(EXCHANGE_FLAG_I_COMMITTED \
215 					 | EXCHANGE_FLAG_HE_COMMITTED)
216 #define EXCHANGE_FLAG_ENCRYPT		0x0004
217 #define EXCHANGE_FLAG_NAT_T_CAP_PEER	0x0008	/* Peer is NAT capable.  */
218 #define EXCHANGE_FLAG_NAT_T_ENABLE	0x0010	/* We are doing NAT-T.  */
219 #define EXCHANGE_FLAG_NAT_T_KEEPALIVE	0x0020	/* We are the NAT:ed peer.  */
220 #define EXCHANGE_FLAG_DPD_CAP_PEER	0x0040	/* Peer is DPD capable.  */
221 #define EXCHANGE_FLAG_NAT_T_RFC		0x0080	/* Peer does RFC NAT-T. */
222 #define EXCHANGE_FLAG_NAT_T_DRAFT	0x0100	/* Peer does draft NAT-T.*/
223 #define EXCHANGE_FLAG_OPENBSD		0x0200	/* Peer is OpenBSD */
224 
225 extern int      exchange_add_certs(struct message *);
226 extern int      exchange_add_certreqs(struct message *);
227 extern void     exchange_finalize(struct message *);
228 extern void     exchange_free(struct exchange *);
229 extern void     exchange_free_aca_list(struct exchange *);
230 extern void     exchange_establish(char *name, void (*)(struct exchange *,
231 		    void *, int), void *, int);
232 extern void	exchange_establish_p1(struct transport *, u_int8_t, u_int32_t,
233 		    char *, void *, void (*)(struct exchange *, void *, int),
234 		    void *, int);
235 extern void     exchange_establish_p2(struct sa *, u_int8_t, char *, void *,
236 		    void (*)(struct exchange *, void *, int), void *);
237 extern int      exchange_gen_nonce(struct message *, size_t);
238 extern void     exchange_init(void);
239 extern struct exchange *exchange_lookup(u_int8_t *, int);
240 extern struct exchange *exchange_lookup_by_name(char *, int);
241 extern struct exchange *exchange_lookup_from_icookie(u_int8_t *);
242 extern void     exchange_report(void);
243 extern void     exchange_run(struct message *);
244 extern int      exchange_save_nonce(struct message *);
245 extern int      exchange_save_certreq(struct message *);
246 extern int16_t *exchange_script(struct exchange *);
247 extern struct exchange *exchange_setup_p1(struct message *, u_int32_t);
248 extern struct exchange *exchange_setup_p2(struct message *, u_int8_t);
249 extern void     exchange_upgrade_p1(struct message *);
250 
251 #endif				/* _EXCHANGE_H_ */
252