1 /* site.c - manage communication with a remote network site */
3 /* The 'site' code doesn't know anything about the structure of the
4 packets it's transmitting. In fact, under the new netlink
5 configuration scheme it doesn't need to know anything at all about
6 IP addresses, except how to contact its peer. This means it could
7 potentially be used to tunnel other protocols too (IPv6, IPX, plain
8 old Ethernet frames) if appropriate netlink code can be written
9 (and that ought not to be too hard, eg. using the TUN/TAP device to
10 pretend to be an Ethernet interface). */
12 /* At some point in the future the netlink code will be asked for
13 configuration information to go in the PING/PONG packets at the end
14 of the key exchange. */
21 #include <sys/socket.h>
25 #include "unaligned.h"
28 #define SETUP_BUFFER_LEN 2048
30 #define DEFAULT_KEY_LIFETIME (3600*1000) /* [ms] */
31 #define DEFAULT_KEY_RENEGOTIATE_GAP (5*60*1000) /* [ms] */
32 #define DEFAULT_SETUP_RETRIES 5
33 #define DEFAULT_SETUP_RETRY_INTERVAL (2*1000) /* [ms] */
34 #define DEFAULT_WAIT_TIME (20*1000) /* [ms] */
36 #define DEFAULT_MOBILE_KEY_LIFETIME (2*24*3600*1000) /* [ms] */
37 #define DEFAULT_MOBILE_KEY_RENEGOTIATE_GAP (12*3600*1000) /* [ms] */
38 #define DEFAULT_MOBILE_SETUP_RETRIES 30
39 #define DEFAULT_MOBILE_SETUP_RETRY_INTERVAL (1*1000) /* [ms] */
40 #define DEFAULT_MOBILE_WAIT_TIME (10*1000) /* [ms] */
42 #define DEFAULT_MOBILE_PEER_EXPIRY (2*60) /* [s] */
43 #define DEFAULT_MOBILE_PEERS_MAX 3 /* send at most this many copies (default) */
45 /* Each site can be in one of several possible states. */
48 SITE_STOP - nothing is allowed to happen; tunnel is down;
49 all session keys have been erased
50 -> SITE_RUN upon external instruction
51 SITE_RUN - site up, maybe with valid key
52 -> SITE_RESOLVE upon outgoing packet and no valid key
53 we start name resolution for the other end of the tunnel
54 -> SITE_SENTMSG2 upon valid incoming message 1 and suitable time
55 we send an appropriate message 2
56 SITE_RESOLVE - waiting for name resolution
57 -> SITE_SENTMSG1 upon successful resolution
58 we send an appropriate message 1
59 -> SITE_SENTMSG2 upon valid incoming message 1 (then abort resolution)
60 we abort resolution and
61 -> SITE_WAIT on timeout or resolution failure
63 -> SITE_SENTMSG2 upon valid incoming message 1 from higher priority end
64 -> SITE_SENTMSG3 upon valid incoming message 2
65 -> SITE_WAIT on timeout
67 -> SITE_SENTMSG4 upon valid incoming message 3
68 -> SITE_WAIT on timeout
70 -> SITE_SENTMSG5 upon valid incoming message 4
71 -> SITE_WAIT on timeout
73 -> SITE_RUN upon valid incoming message 5
74 -> SITE_WAIT on timeout
76 -> SITE_RUN upon valid incoming message 6
77 -> SITE_WAIT on timeout
78 SITE_WAIT - failed to establish key; do nothing for a while
79 -> SITE_RUN on timeout
84 #define SITE_RESOLVE 2
85 #define SITE_SENTMSG1 3
86 #define SITE_SENTMSG2 4
87 #define SITE_SENTMSG3 5
88 #define SITE_SENTMSG4 6
89 #define SITE_SENTMSG5 7
92 static cstring_t state_name(uint32_t state)
95 case 0: return "STOP";
97 case 2: return "RESOLVE";
98 case 3: return "SENTMSG1";
99 case 4: return "SENTMSG2";
100 case 5: return "SENTMSG3";
101 case 6: return "SENTMSG4";
102 case 7: return "SENTMSG5";
103 case 8: return "WAIT";
104 default: return "*bad state*";
110 #define LOG_UNEXPECTED 0x00000001
111 #define LOG_SETUP_INIT 0x00000002
112 #define LOG_SETUP_TIMEOUT 0x00000004
113 #define LOG_ACTIVATE_KEY 0x00000008
114 #define LOG_TIMEOUT_KEY 0x00000010
115 #define LOG_SEC 0x00000020
116 #define LOG_STATE 0x00000040
117 #define LOG_DROP 0x00000080
118 #define LOG_DUMP 0x00000100
119 #define LOG_ERROR 0x00000400
120 #define LOG_PEER_ADDRS 0x00000800
122 static struct flagstr log_event_table[]={
123 { "unexpected", LOG_UNEXPECTED },
124 { "setup-init", LOG_SETUP_INIT },
125 { "setup-timeout", LOG_SETUP_TIMEOUT },
126 { "activate-key", LOG_ACTIVATE_KEY },
127 { "timeout-key", LOG_TIMEOUT_KEY },
128 { "security", LOG_SEC },
129 { "state-change", LOG_STATE },
130 { "packet-drop", LOG_DROP },
131 { "dump-packets", LOG_DUMP },
132 { "errors", LOG_ERROR },
133 { "peer-addrs", LOG_PEER_ADDRS },
134 { "default", LOG_SETUP_INIT|LOG_SETUP_TIMEOUT|
135 LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR },
136 { "all", 0xffffffff },
141 /***** TRANSPORT PEERS declarations *****/
143 /* Details of "mobile peer" semantics:
145 - We record mobile_peers_max peer address/port numbers ("peers")
146 for key setup, and separately mobile_peers_max for data
147 transfer. If these lists fill up, we retain the newest peers.
148 (For non-mobile peers we only record one of each.)
150 - Outgoing packets are sent to every recorded peer in the
153 - Data transfer peers are straightforward: whenever we successfully
154 process a data packet, we record the peer. Also, whenever we
155 successfully complete a key setup, we merge the key setup
156 peers into the data transfer peers.
158 (For "non-mobile" peers we simply copy the peer used for
159 successful key setup, and don't change the peer otherwise.)
161 - Key setup peers are slightly more complicated.
163 Whenever we receive and successfully process a key exchange
164 packet, we record the peer.
166 Whenever we try to initiate a key setup, we copy the list of data
167 transfer peers and use it for key setup. But we also look to see
168 if the config supplies an address and port number and if so we
169 add that as a key setup peer (possibly evicting one of the data
170 transfer peers we just copied).
172 (For "non-mobile" peers, if we if we have a configured peer
173 address and port, we always use that; otherwise if we have a
174 current data peer address we use that; otherwise we do not
175 attempt to initiate a key setup for lack of a peer address.)
177 "Record the peer" means
178 1. expire any peers last seen >120s ("mobile-peer-expiry") ago
179 2. add the peer of the just received packet to the applicable list
180 (possibly evicting older entries)
181 NB that we do not expire peers until an incoming packet arrives.
185 #define MAX_MOBILE_PEERS_MAX 5 /* send at most this many copies, compiled max */
189 struct comm_addr addr;
193 /* configuration information */
194 /* runtime information */
196 transport_peer peers[MAX_MOBILE_PEERS_MAX];
199 static void transport_peers_clear(struct site *st, transport_peers *peers);
200 static int transport_peers_valid(transport_peers *peers);
201 static void transport_peers_copy(struct site *st, transport_peers *dst,
202 const transport_peers *src);
204 static void transport_setup_msgok(struct site *st, const struct comm_addr *a);
205 static void transport_data_msgok(struct site *st, const struct comm_addr *a);
206 static bool_t transport_compute_setupinit_peers(struct site *st,
207 const struct comm_addr *configured_addr /* 0 if none or not found */);
208 static void transport_record_peer(struct site *st, transport_peers *peers,
209 const struct comm_addr *addr, const char *m);
211 static void transport_xmit(struct site *st, transport_peers *peers,
212 struct buffer_if *buf, bool_t candebug);
214 /***** END of transport peers declarations *****/
218 struct transform_inst_if *transform;
219 uint64_t key_timeout; /* End of life of current key */
220 uint32_t remote_session_id;
226 /* configuration information */
229 bool_t peer_mobile; /* Mobile client support */
230 int32_t transport_peers_max;
231 string_t tunname; /* localname<->remotename by default, used in logs */
232 string_t address; /* DNS name for bootstrapping, optional */
233 int remoteport; /* Port for bootstrapping, optional */
234 struct netlink_if *netlink;
235 struct comm_if **comms;
237 struct resolver_if *resolver;
239 struct random_if *random;
240 struct rsaprivkey_if *privkey;
241 struct rsapubkey_if *pubkey;
242 struct transform_if *transform;
244 struct hash_if *hash;
246 uint32_t index; /* Index of this site */
247 int32_t setup_retries; /* How many times to send setup packets */
248 int32_t setup_retry_interval; /* Initial timeout for setup packets */
249 int32_t wait_timeout; /* How long to wait if setup unsuccessful */
250 int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
251 int32_t key_lifetime; /* How long a key lasts once set up */
252 int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
253 after this time, initiate a new
256 uint8_t *setupsig; /* Expected signature of incoming MSG1 packets */
257 int32_t setupsiglen; /* Allows us to discard packets quickly if
258 they are not for us */
259 bool_t setup_priority; /* Do we have precedence if both sites emit
260 message 1 simultaneously? */
263 /* runtime information */
265 uint64_t now; /* Most recently seen time */
267 /* The currently established session */
268 struct data_key current;
269 struct data_key auxiliary_key;
270 bool_t auxiliary_is_new;
271 uint64_t renegotiate_key_time; /* When we can negotiate a new key */
272 uint64_t auxiliary_renegotiate_key_time;
273 transport_peers peers; /* Current address(es) of peer for data traffic */
275 /* The current key setup protocol exchange. We can only be
276 involved in one of these at a time. There's a potential for
277 denial of service here (the attacker keeps sending a setup
278 packet; we keep trying to continue the exchange, and have to
279 timeout before we can listen for another setup packet); perhaps
280 we should keep a list of 'bad' sources for setup packets. */
281 uint32_t setup_session_id;
282 transport_peers setup_peers;
283 uint8_t localN[NONCELEN]; /* Nonces for key exchange */
284 uint8_t remoteN[NONCELEN];
285 struct buffer_if buffer; /* Current outgoing key exchange packet */
286 struct buffer_if scratch;
287 int32_t retries; /* Number of retries remaining */
288 uint64_t timeout; /* Timeout for current state */
290 uint8_t *sharedsecret;
291 uint32_t sharedsecretlen;
292 struct transform_inst_if *new_transform; /* For key setup/verify */
295 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
303 if (event&st->log_events) {
305 case LOG_UNEXPECTED: class=M_INFO; break;
306 case LOG_SETUP_INIT: class=M_INFO; break;
307 case LOG_SETUP_TIMEOUT: class=M_NOTICE; break;
308 case LOG_ACTIVATE_KEY: class=M_INFO; break;
309 case LOG_TIMEOUT_KEY: class=M_INFO; break;
310 case LOG_SEC: class=M_SECURITY; break;
311 case LOG_STATE: class=M_DEBUG; break;
312 case LOG_DROP: class=M_DEBUG; break;
313 case LOG_DUMP: class=M_DEBUG; break;
314 case LOG_ERROR: class=M_ERR; break;
315 case LOG_PEER_ADDRS: class=M_DEBUG; break;
316 default: class=M_ERR; break;
319 vsnprintf(buf,sizeof(buf),msg,ap);
320 st->log->log(st->log->st,class,"%s: %s",st->tunname,buf);
325 static void set_link_quality(struct site *st);
326 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
327 static void delete_one_key(struct site *st, struct data_key *key,
328 const char *reason /* may be 0 meaning don't log*/,
329 const char *which /* ignored if !reasonn */,
330 uint32_t loglevel /* ignored if !reasonn */);
331 static bool_t initiate_key_setup(struct site *st, cstring_t reason);
332 static void enter_state_run(struct site *st);
333 static bool_t enter_state_resolve(struct site *st);
334 static bool_t enter_new_state(struct site *st,uint32_t next);
335 static void enter_state_wait(struct site *st);
336 static void activate_new_key(struct site *st);
338 static bool_t current_valid(struct site *st)
340 return st->current.transform->valid(st->current.transform->st);
343 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
344 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
345 #define CHECK_TYPE(b,t) do { uint32_t type; \
346 CHECK_AVAIL((b),4); \
347 type=buf_unprepend_uint32((b)); \
348 if (type!=(t)) return False; } while(0)
367 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
368 out using a transform of config data supplied by netlink */
369 static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what)
375 st->retries=st->setup_retries;
376 BUF_ALLOC(&st->buffer,what);
377 buffer_init(&st->buffer,0);
378 buf_append_uint32(&st->buffer,
379 (type==LABEL_MSG1?0:st->setup_session_id));
380 buf_append_uint32(&st->buffer,st->index);
381 buf_append_uint32(&st->buffer,type);
382 buf_append_string(&st->buffer,st->localname);
383 buf_append_string(&st->buffer,st->remotename);
384 memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN);
385 if (type==LABEL_MSG1) return True;
386 memcpy(buf_append(&st->buffer,NONCELEN),st->remoteN,NONCELEN);
387 if (type==LABEL_MSG2) return True;
389 if (hacky_par_mid_failnow()) return False;
391 dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
392 buf_append_string(&st->buffer,dhpub);
394 hash=safe_malloc(st->hash->len, "generate_msg");
395 hst=st->hash->init();
396 st->hash->update(hst,st->buffer.start,st->buffer.size);
397 st->hash->final(hst,hash);
398 sig=st->privkey->sign(st->privkey->st,hash,st->hash->len);
399 buf_append_string(&st->buffer,sig);
405 static bool_t unpick_msg(struct site *st, uint32_t type,
406 struct buffer_if *msg, struct msg *m)
408 m->hashstart=msg->start;
410 m->dest=buf_unprepend_uint32(msg);
412 m->source=buf_unprepend_uint32(msg);
413 CHECK_TYPE(msg,type);
415 m->remlen=buf_unprepend_uint16(msg);
416 CHECK_AVAIL(msg,m->remlen);
417 m->remote=buf_unprepend(msg,m->remlen);
419 m->loclen=buf_unprepend_uint16(msg);
420 CHECK_AVAIL(msg,m->loclen);
421 m->local=buf_unprepend(msg,m->loclen);
422 CHECK_AVAIL(msg,NONCELEN);
423 m->nR=buf_unprepend(msg,NONCELEN);
424 if (type==LABEL_MSG1) {
428 CHECK_AVAIL(msg,NONCELEN);
429 m->nL=buf_unprepend(msg,NONCELEN);
430 if (type==LABEL_MSG2) {
435 m->pklen=buf_unprepend_uint16(msg);
436 CHECK_AVAIL(msg,m->pklen);
437 m->pk=buf_unprepend(msg,m->pklen);
438 m->hashlen=msg->start-m->hashstart;
440 m->siglen=buf_unprepend_uint16(msg);
441 CHECK_AVAIL(msg,m->siglen);
442 m->sig=buf_unprepend(msg,m->siglen);
447 static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
450 if (type==LABEL_MSG1) return True;
452 /* Check that the site names and our nonce have been sent
453 back correctly, and then store our peer's nonce. */
454 if (memcmp(m->remote,st->remotename,strlen(st->remotename)!=0)) {
455 *error="wrong remote site name";
458 if (memcmp(m->local,st->localname,strlen(st->localname)!=0)) {
459 *error="wrong local site name";
462 if (memcmp(m->nL,st->localN,NONCELEN)!=0) {
463 *error="wrong locally-generated nonce";
466 if (type==LABEL_MSG2) return True;
467 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
468 *error="wrong remotely-generated nonce";
471 if (type==LABEL_MSG3) return True;
472 if (type==LABEL_MSG4) return True;
473 *error="unknown message type";
477 static bool_t generate_msg1(struct site *st)
479 st->random->generate(st->random->st,NONCELEN,st->localN);
480 return generate_msg(st,LABEL_MSG1,"site:MSG1");
483 static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
484 const struct comm_addr *src)
488 /* We've already determined we're in an appropriate state to
489 process an incoming MSG1, and that the MSG1 has correct values
492 if (!unpick_msg(st,LABEL_MSG1,msg1,&m)) return False;
494 transport_record_peer(st,&st->setup_peers,src,"msg1");
495 st->setup_session_id=m.source;
496 memcpy(st->remoteN,m.nR,NONCELEN);
500 static bool_t generate_msg2(struct site *st)
502 st->random->generate(st->random->st,NONCELEN,st->localN);
503 return generate_msg(st,LABEL_MSG2,"site:MSG2");
506 static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
507 const struct comm_addr *src)
512 if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False;
513 if (!check_msg(st,LABEL_MSG2,&m,&err)) {
514 slog(st,LOG_SEC,"msg2: %s",err);
517 st->setup_session_id=m.source;
518 memcpy(st->remoteN,m.nR,NONCELEN);
522 static bool_t generate_msg3(struct site *st)
524 /* Now we have our nonce and their nonce. Think of a secret key,
525 and create message number 3. */
526 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
527 return generate_msg(st,LABEL_MSG3,"site:MSG3");
530 static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
531 const struct comm_addr *src)
538 if (!unpick_msg(st,LABEL_MSG3,msg3,&m)) return False;
539 if (!check_msg(st,LABEL_MSG3,&m,&err)) {
540 slog(st,LOG_SEC,"msg3: %s",err);
544 /* Check signature and store g^x mod m */
545 hash=safe_malloc(st->hash->len, "process_msg3");
546 hst=st->hash->init();
547 st->hash->update(hst,m.hashstart,m.hashlen);
548 st->hash->final(hst,hash);
549 /* Terminate signature with a '0' - cheating, but should be ok */
551 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) {
552 slog(st,LOG_SEC,"msg3 signature failed check!");
558 /* Terminate their DH public key with a '0' */
560 /* Invent our DH secret key */
561 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
563 /* Generate the shared key */
564 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk,
565 st->sharedsecret,st->sharedsecretlen);
567 /* Set up the transform */
568 st->new_transform->setkey(st->new_transform->st,st->sharedsecret,
569 st->sharedsecretlen,st->setup_priority);
574 static bool_t generate_msg4(struct site *st)
576 /* We have both nonces, their public key and our private key. Generate
577 our public key, sign it and send it to them. */
578 return generate_msg(st,LABEL_MSG4,"site:MSG4");
581 static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
582 const struct comm_addr *src)
589 if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
590 if (!check_msg(st,LABEL_MSG4,&m,&err)) {
591 slog(st,LOG_SEC,"msg4: %s",err);
595 /* Check signature and store g^x mod m */
596 hash=safe_malloc(st->hash->len, "process_msg4");
597 hst=st->hash->init();
598 st->hash->update(hst,m.hashstart,m.hashlen);
599 st->hash->final(hst,hash);
600 /* Terminate signature with a '0' - cheating, but should be ok */
602 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) {
603 slog(st,LOG_SEC,"msg4 signature failed check!");
609 /* Terminate their DH public key with a '0' */
611 /* Generate the shared key */
612 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk,
613 st->sharedsecret,st->sharedsecretlen);
614 /* Set up the transform */
615 st->new_transform->setkey(st->new_transform->st,st->sharedsecret,
616 st->sharedsecretlen,st->setup_priority);
627 static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0,
631 m->dest=buf_unprepend_uint32(msg0);
633 m->source=buf_unprepend_uint32(msg0);
635 m->type=buf_unprepend_uint32(msg0);
637 /* Leaves transformed part of buffer untouched */
640 static bool_t generate_msg5(struct site *st)
642 cstring_t transform_err;
644 BUF_ALLOC(&st->buffer,"site:MSG5");
645 /* We are going to add four words to the message */
646 buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
647 /* Give the netlink code an opportunity to put its own stuff in the
648 message (configuration information, etc.) */
649 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
650 st->new_transform->forwards(st->new_transform->st,&st->buffer,
652 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
653 buf_prepend_uint32(&st->buffer,st->index);
654 buf_prepend_uint32(&st->buffer,st->setup_session_id);
656 st->retries=st->setup_retries;
660 static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
661 const struct comm_addr *src,
662 struct transform_inst_if *transform)
665 cstring_t transform_err;
667 if (!unpick_msg0(st,msg5,&m)) return False;
669 if (transform->reverse(transform->st,msg5,&transform_err)) {
670 /* There's a problem */
671 slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
674 /* Buffer should now contain untransformed PING packet data */
676 if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) {
677 slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
680 /* Older versions of secnet used to write some config data here
681 * which we ignore. So we don't CHECK_EMPTY */
685 static void create_msg6(struct site *st, struct transform_inst_if *transform,
688 cstring_t transform_err;
690 BUF_ALLOC(&st->buffer,"site:MSG6");
691 /* We are going to add four words to the message */
692 buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
693 /* Give the netlink code an opportunity to put its own stuff in the
694 message (configuration information, etc.) */
695 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
696 transform->forwards(transform->st,&st->buffer,&transform_err);
697 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
698 buf_prepend_uint32(&st->buffer,st->index);
699 buf_prepend_uint32(&st->buffer,session_id);
702 static bool_t generate_msg6(struct site *st)
704 create_msg6(st,st->new_transform,st->setup_session_id);
705 st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
709 static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
710 const struct comm_addr *src)
713 cstring_t transform_err;
715 if (!unpick_msg0(st,msg6,&m)) return False;
717 if (st->new_transform->reverse(st->new_transform->st,
718 msg6,&transform_err)) {
719 /* There's a problem */
720 slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
723 /* Buffer should now contain untransformed PING packet data */
725 if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) {
726 slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
729 /* Older versions of secnet used to write some config data here
730 * which we ignore. So we don't CHECK_EMPTY */
734 static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0)
736 cstring_t transform_err, auxkey_err, newkey_err="n/a";
740 if (!unpick_msg0(st,msg0,&m)) return False;
742 /* Keep a copy so we can try decrypting it with multiple keys */
743 buffer_copy(&st->scratch, msg0);
745 problem = st->current.transform->reverse(st->current.transform->st,
746 msg0,&transform_err);
748 if (!st->auxiliary_is_new)
749 delete_one_key(st,&st->auxiliary_key,
750 "peer has used new key","auxiliary key",LOG_SEC);
755 slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
759 buffer_copy(msg0, &st->scratch);
760 problem = st->auxiliary_key.transform->reverse
761 (st->auxiliary_key.transform->st,msg0,&auxkey_err);
763 slog(st,LOG_DROP,"processing packet which uses auxiliary key");
764 if (st->auxiliary_is_new) {
765 /* We previously timed out in state SENTMSG5 but it turns
766 * out that our peer did in fact get our MSG5 and is
767 * using the new key. So we should switch to it too. */
768 /* This is a bit like activate_new_key. */
771 st->current=st->auxiliary_key;
774 delete_one_key(st,&st->auxiliary_key,"peer has used new key",
775 "previous key",LOG_SEC);
776 st->auxiliary_is_new=0;
777 st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
782 if (st->state==SITE_SENTMSG5) {
783 buffer_copy(msg0, &st->scratch);
784 if (!st->new_transform->reverse(st->new_transform->st,
786 /* It looks like we didn't get the peer's MSG6 */
787 /* This is like a cut-down enter_new_state(SITE_RUN) */
788 slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
789 BUF_FREE(&st->buffer);
791 activate_new_key(st);
792 return True; /* do process the data in this packet */
796 slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
797 transform_err,auxkey_err,newkey_err);
798 initiate_key_setup(st,"incoming message would not decrypt");
802 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
803 const struct comm_addr *src)
807 if (!decrypt_msg0(st,msg0))
811 type=buf_unprepend_uint32(msg0);
814 /* We must forget about the current session. */
815 delete_keys(st,"request from peer",LOG_SEC);
818 /* Deliver to netlink layer */
819 st->netlink->deliver(st->netlink->st,msg0);
820 transport_data_msgok(st,src);
821 /* See whether we should start negotiating a new key */
822 if (st->now > st->renegotiate_key_time)
823 initiate_key_setup(st,"incoming packet in renegotiation window");
826 slog(st,LOG_SEC,"incoming encrypted message of type %08x "
833 static void dump_packet(struct site *st, struct buffer_if *buf,
834 const struct comm_addr *addr, bool_t incoming)
836 uint32_t dest=ntohl(*(uint32_t *)buf->start);
837 uint32_t source=ntohl(*(uint32_t *)(buf->start+4));
838 uint32_t msgtype=ntohl(*(uint32_t *)(buf->start+8));
840 if (st->log_events & LOG_DUMP)
841 slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x:",
842 st->tunname,incoming?"incoming":"outgoing",
843 dest,source,msgtype);
846 static uint32_t site_status(void *st)
851 static bool_t send_msg(struct site *st)
854 transport_xmit(st, &st->setup_peers, &st->buffer, True);
855 st->timeout=st->now+st->setup_retry_interval;
858 } else if (st->state==SITE_SENTMSG5) {
859 slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key");
860 /* We stash the key we have produced, in case it turns out that
861 * our peer did see our MSG5 after all and starts using it. */
862 /* This is a bit like some of activate_new_key */
863 struct transform_inst_if *t;
864 t=st->auxiliary_key.transform;
865 st->auxiliary_key.transform=st->new_transform;
869 st->auxiliary_is_new=1;
870 st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
871 st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
872 st->auxiliary_key.remote_session_id=st->setup_session_id;
874 enter_state_wait(st);
877 slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet "
878 "(in state %s)",state_name(st->state));
879 enter_state_wait(st);
884 static void site_resolve_callback(void *sst, struct in_addr *address)
887 struct comm_addr ca_buf, *ca_use;
889 if (st->state!=SITE_RESOLVE) {
890 slog(st,LOG_UNEXPECTED,"site_resolve_callback called unexpectedly");
895 ca_buf.comm=st->comms[0];
896 ca_buf.sin.sin_family=AF_INET;
897 ca_buf.sin.sin_port=htons(st->remoteport);
898 ca_buf.sin.sin_addr=*address;
901 slog(st,LOG_ERROR,"resolution of %s failed",st->address);
904 if (transport_compute_setupinit_peers(st,ca_use)) {
905 enter_new_state(st,SITE_SENTMSG1);
907 /* Can't figure out who to try to to talk to */
908 slog(st,LOG_SETUP_INIT,"key exchange failed: cannot find peer address");
913 static bool_t initiate_key_setup(struct site *st, cstring_t reason)
915 if (st->state!=SITE_RUN) return False;
916 slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
918 slog(st,LOG_SETUP_INIT,"resolving peer address");
919 return enter_state_resolve(st);
920 } else if (transport_compute_setupinit_peers(st,0)) {
921 return enter_new_state(st,SITE_SENTMSG1);
923 slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
927 static void activate_new_key(struct site *st)
929 struct transform_inst_if *t;
931 /* We have three transform instances, which we swap between old,
933 t=st->auxiliary_key.transform;
934 st->auxiliary_key.transform=st->current.transform;
935 st->current.transform=st->new_transform;
940 st->auxiliary_is_new=0;
941 st->auxiliary_key.key_timeout=st->current.key_timeout;
942 st->current.key_timeout=st->now+st->key_lifetime;
943 st->renegotiate_key_time=st->now+st->key_renegotiate_time;
944 transport_peers_copy(st,&st->peers,&st->setup_peers);
945 st->current.remote_session_id=st->setup_session_id;
947 slog(st,LOG_ACTIVATE_KEY,"new key activated");
951 static void delete_one_key(struct site *st, struct data_key *key,
952 cstring_t reason, cstring_t which, uint32_t loglevel)
954 if (!key->transform->valid(key->transform->st)) return;
955 if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
956 key->transform->delkey(key->transform->st);
960 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
962 if (current_valid(st)) {
963 slog(st,loglevel,"session closed (%s)",reason);
965 delete_one_key(st,&st->current,0,0,0);
966 set_link_quality(st);
968 delete_one_key(st,&st->auxiliary_key,0,0,0);
971 static void state_assert(struct site *st, bool_t ok)
973 if (!ok) fatal("site:state_assert");
976 static void enter_state_stop(struct site *st)
980 delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
981 st->new_transform->delkey(st->new_transform->st);
984 static void set_link_quality(struct site *st)
987 if (current_valid(st))
988 quality=LINK_QUALITY_UP;
989 else if (st->state==SITE_WAIT || st->state==SITE_STOP)
990 quality=LINK_QUALITY_DOWN;
991 else if (st->address)
992 quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
993 else if (transport_peers_valid(&st->peers))
994 quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
996 quality=LINK_QUALITY_DOWN;
998 st->netlink->set_quality(st->netlink->st,quality);
1001 static void enter_state_run(struct site *st)
1003 slog(st,LOG_STATE,"entering state RUN");
1007 st->setup_session_id=0;
1008 transport_peers_clear(st,&st->setup_peers);
1009 memset(st->localN,0,NONCELEN);
1010 memset(st->remoteN,0,NONCELEN);
1011 st->new_transform->delkey(st->new_transform->st);
1012 memset(st->dhsecret,0,st->dh->len);
1013 memset(st->sharedsecret,0,st->sharedsecretlen);
1014 set_link_quality(st);
1017 static bool_t enter_state_resolve(struct site *st)
1019 state_assert(st,st->state==SITE_RUN);
1020 slog(st,LOG_STATE,"entering state RESOLVE");
1021 st->state=SITE_RESOLVE;
1022 st->resolver->request(st->resolver->st,st->address,
1023 site_resolve_callback,st);
1027 static bool_t enter_new_state(struct site *st, uint32_t next)
1029 bool_t (*gen)(struct site *st);
1032 slog(st,LOG_STATE,"entering state %s",state_name(next));
1035 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
1039 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1040 st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
1044 state_assert(st,st->state==SITE_SENTMSG1);
1045 BUF_FREE(&st->buffer);
1049 state_assert(st,st->state==SITE_SENTMSG2);
1050 BUF_FREE(&st->buffer);
1054 state_assert(st,st->state==SITE_SENTMSG3);
1055 BUF_FREE(&st->buffer);
1059 state_assert(st,st->state==SITE_SENTMSG4);
1060 BUF_FREE(&st->buffer);
1065 fatal("enter_new_state(%s): invalid new state",state_name(next));
1069 if (hacky_par_start_failnow()) return False;
1071 r= gen(st) && send_msg(st);
1074 st->setup_retries, st->setup_retry_interval,
1079 if (next==SITE_RUN) {
1080 BUF_FREE(&st->buffer); /* Never reused */
1081 st->timeout=0; /* Never retransmit */
1082 activate_new_key(st);
1086 slog(st,LOG_ERROR,"error entering state %s",state_name(next));
1087 st->buffer.free=False; /* Unconditionally use the buffer; it may be
1088 in either state, and enter_state_wait() will
1090 enter_state_wait(st);
1094 /* msg7 tells our peer that we're about to forget our key */
1095 static bool_t send_msg7(struct site *st, cstring_t reason)
1097 cstring_t transform_err;
1099 if (current_valid(st) && st->buffer.free
1100 && transport_peers_valid(&st->peers)) {
1101 BUF_ALLOC(&st->buffer,"site:MSG7");
1102 buffer_init(&st->buffer,st->transform->max_start_pad+(4*3));
1103 buf_append_uint32(&st->buffer,LABEL_MSG7);
1104 buf_append_string(&st->buffer,reason);
1105 st->current.transform->forwards(st->current.transform->st,
1106 &st->buffer, &transform_err);
1107 buf_prepend_uint32(&st->buffer,LABEL_MSG0);
1108 buf_prepend_uint32(&st->buffer,st->index);
1109 buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
1110 transport_xmit(st,&st->peers,&st->buffer,True);
1111 BUF_FREE(&st->buffer);
1117 /* We go into this state if our peer becomes uncommunicative. Similar to
1118 the "stop" state, we forget all session keys for a while, before
1119 re-entering the "run" state. */
1120 static void enter_state_wait(struct site *st)
1122 slog(st,LOG_STATE,"entering state WAIT");
1123 st->timeout=st->now+st->wait_timeout;
1124 st->state=SITE_WAIT;
1125 set_link_quality(st);
1126 BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
1127 /* XXX Erase keys etc. */
1130 static inline void site_settimeout(uint64_t timeout, int *timeout_io)
1133 int64_t offset=timeout-*now;
1134 if (offset<0) offset=0;
1135 if (offset>INT_MAX) offset=INT_MAX;
1136 if (*timeout_io<0 || offset<*timeout_io)
1141 static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
1144 struct site *st=sst;
1146 *nfds_io=0; /* We don't use any file descriptors */
1149 /* Work out when our next timeout is. The earlier of 'timeout' or
1150 'current.key_timeout'. A stored value of '0' indicates no timeout
1152 site_settimeout(st->timeout, timeout_io);
1153 site_settimeout(st->current.key_timeout, timeout_io);
1154 site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
1156 return 0; /* success */
1159 static void check_expiry(struct site *st, struct data_key *key,
1162 if (key->key_timeout && *now>key->key_timeout) {
1163 delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
1167 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1168 static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
1170 struct site *st=sst;
1173 if (st->timeout && *now>st->timeout) {
1175 if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) {
1176 if (!hacky_par_start_failnow())
1178 } else if (st->state==SITE_WAIT) {
1179 enter_state_run(st);
1181 slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d",
1185 check_expiry(st,&st->current,"current key");
1186 check_expiry(st,&st->auxiliary_key,"auxiliary key");
1189 /* This function is called by the netlink device to deliver packets
1190 intended for the remote network. The packet is in "raw" wire
1191 format, but is guaranteed to be word-aligned. */
1192 static void site_outgoing(void *sst, struct buffer_if *buf)
1194 struct site *st=sst;
1195 cstring_t transform_err;
1197 if (st->state==SITE_STOP) {
1202 /* In all other states we consider delivering the packet if we have
1203 a valid key and a valid address to send it to. */
1204 if (current_valid(st) && transport_peers_valid(&st->peers)) {
1205 /* Transform it and send it */
1207 buf_prepend_uint32(buf,LABEL_MSG9);
1208 st->current.transform->forwards(st->current.transform->st,
1209 buf, &transform_err);
1210 buf_prepend_uint32(buf,LABEL_MSG0);
1211 buf_prepend_uint32(buf,st->index);
1212 buf_prepend_uint32(buf,st->current.remote_session_id);
1213 transport_xmit(st,&st->peers,buf,False);
1219 slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size);
1221 initiate_key_setup(st,"outgoing packet");
1224 /* This function is called by the communication device to deliver
1225 packets from our peers. */
1226 static bool_t site_incoming(void *sst, struct buffer_if *buf,
1227 const struct comm_addr *source)
1229 struct site *st=sst;
1231 if (buf->size < 12) return False;
1233 uint32_t dest=ntohl(*(uint32_t *)buf->start);
1236 /* It could be for any site - it should have LABEL_MSG1 and
1237 might have our name and our peer's name in it */
1238 if (buf->size<(st->setupsiglen+8+NONCELEN)) return False;
1239 if (memcmp(buf->start+8,st->setupsig,st->setupsiglen)==0) {
1240 /* It's addressed to us. Decide what to do about it. */
1241 dump_packet(st,buf,source,True);
1242 if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1243 st->state==SITE_WAIT) {
1244 /* We should definitely process it */
1245 if (process_msg1(st,buf,source)) {
1246 slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
1247 enter_new_state(st,SITE_SENTMSG2);
1249 slog(st,LOG_ERROR,"failed to process incoming msg1");
1253 } else if (st->state==SITE_SENTMSG1) {
1254 /* We've just sent a message 1! They may have crossed on
1255 the wire. If we have priority then we ignore the
1256 incoming one, otherwise we process it as usual. */
1257 if (st->setup_priority) {
1259 slog(st,LOG_DUMP,"crossed msg1s; we are higher "
1260 "priority => ignore incoming msg1");
1263 slog(st,LOG_DUMP,"crossed msg1s; we are lower "
1264 "priority => use incoming msg1");
1265 if (process_msg1(st,buf,source)) {
1266 BUF_FREE(&st->buffer); /* Free our old message 1 */
1267 enter_new_state(st,SITE_SENTMSG2);
1269 slog(st,LOG_ERROR,"failed to process an incoming "
1270 "crossed msg1 (we have low priority)");
1276 /* The message 1 was received at an unexpected stage of the
1277 key setup. XXX POLICY - what do we do? */
1278 slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
1282 return False; /* Not for us. */
1284 if (dest==st->index) {
1285 /* Explicitly addressed to us */
1286 uint32_t msgtype=ntohl(get_uint32(buf->start+8));
1287 if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True);
1290 /* If the source is our current peer then initiate a key setup,
1291 because our peer's forgotten the key */
1292 if (get_uint32(buf->start+4)==st->current.remote_session_id) {
1293 initiate_key_setup(st,"received a NAK");
1295 slog(st,LOG_SEC,"bad incoming NAK");
1299 process_msg0(st,buf,source);
1302 /* Setup packet: should not have been explicitly addressed
1304 slog(st,LOG_SEC,"incoming explicitly addressed msg1");
1307 /* Setup packet: expected only in state SENTMSG1 */
1308 if (st->state!=SITE_SENTMSG1) {
1309 slog(st,LOG_UNEXPECTED,"unexpected MSG2");
1310 } else if (process_msg2(st,buf,source)) {
1311 transport_setup_msgok(st,source);
1312 enter_new_state(st,SITE_SENTMSG3);
1314 slog(st,LOG_SEC,"invalid MSG2");
1318 /* Setup packet: expected only in state SENTMSG2 */
1319 if (st->state!=SITE_SENTMSG2) {
1320 slog(st,LOG_UNEXPECTED,"unexpected MSG3");
1321 } else if (process_msg3(st,buf,source)) {
1322 transport_setup_msgok(st,source);
1323 enter_new_state(st,SITE_SENTMSG4);
1325 slog(st,LOG_SEC,"invalid MSG3");
1329 /* Setup packet: expected only in state SENTMSG3 */
1330 if (st->state!=SITE_SENTMSG3) {
1331 slog(st,LOG_UNEXPECTED,"unexpected MSG4");
1332 } else if (process_msg4(st,buf,source)) {
1333 transport_setup_msgok(st,source);
1334 enter_new_state(st,SITE_SENTMSG5);
1336 slog(st,LOG_SEC,"invalid MSG4");
1340 /* Setup packet: expected only in state SENTMSG4 */
1341 /* (may turn up in state RUN if our return MSG6 was lost
1342 and the new key has already been activated. In that
1343 case we discard it. The peer will realise that we
1344 are using the new key when they see our data packets.
1345 Until then the peer's data packets to us get discarded. */
1346 if (st->state==SITE_SENTMSG4) {
1347 if (process_msg5(st,buf,source,st->new_transform)) {
1348 transport_setup_msgok(st,source);
1349 enter_new_state(st,SITE_RUN);
1351 slog(st,LOG_SEC,"invalid MSG5");
1353 } else if (st->state==SITE_RUN) {
1354 if (process_msg5(st,buf,source,st->current.transform)) {
1355 slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
1356 transport_setup_msgok(st,source);
1357 create_msg6(st,st->current.transform,
1358 st->current.remote_session_id);
1359 transport_xmit(st,&st->peers,&st->buffer,True);
1360 BUF_FREE(&st->buffer);
1362 slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
1365 slog(st,LOG_UNEXPECTED,"unexpected MSG5");
1369 /* Setup packet: expected only in state SENTMSG5 */
1370 if (st->state!=SITE_SENTMSG5) {
1371 slog(st,LOG_UNEXPECTED,"unexpected MSG6");
1372 } else if (process_msg6(st,buf,source)) {
1373 BUF_FREE(&st->buffer); /* Free message 5 */
1374 transport_setup_msgok(st,source);
1375 activate_new_key(st);
1377 slog(st,LOG_SEC,"invalid MSG6");
1381 slog(st,LOG_SEC,"received message of unknown type 0x%08x",
1392 static void site_control(void *vst, bool_t run)
1394 struct site *st=vst;
1395 if (run) enter_state_run(st);
1396 else enter_state_stop(st);
1399 static void site_phase_hook(void *sst, uint32_t newphase)
1401 struct site *st=sst;
1403 /* The program is shutting down; tell our peer */
1404 send_msg7(st,"shutting down");
1407 static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
1410 static uint32_t index_sequence;
1416 st=safe_malloc(sizeof(*st),"site_apply");
1418 st->cl.description="site";
1419 st->cl.type=CL_SITE;
1421 st->cl.interface=&st->ops;
1423 st->ops.control=site_control;
1424 st->ops.status=site_status;
1426 /* First parameter must be a dict */
1427 item=list_elem(args,0);
1428 if (!item || item->type!=t_dict)
1429 cfgfatal(loc,"site","parameter must be a dictionary\n");
1431 dict=item->data.dict;
1432 st->localname=dict_read_string(dict, "local-name", True, "site", loc);
1433 st->remotename=dict_read_string(dict, "name", True, "site", loc);
1435 st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
1436 bool_t local_mobile=
1437 dict_read_bool(dict,"local-mobile",False,"site",loc,False);
1439 /* Sanity check (which also allows the 'sites' file to include
1440 site() closures for all sites including our own): refuse to
1441 talk to ourselves */
1442 if (strcmp(st->localname,st->remotename)==0) {
1443 Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
1445 if (st->peer_mobile != local_mobile)
1446 cfgfatal(loc,"site","site %s's peer-mobile=%d"
1447 " but our local-mobile=%d\n",
1448 st->localname, st->peer_mobile, local_mobile);
1452 if (st->peer_mobile && local_mobile) {
1453 Message(M_WARNING,"site %s: site is mobile but so are we"
1454 " -> ignoring this site\n", st->remotename);
1459 assert(index_sequence < 0xffffffffUL);
1460 st->index = ++index_sequence;
1461 st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
1463 list_t *comms_cfg=dict_lookup(dict,"comm");
1464 if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n");
1465 st->ncomms=list_length(comms_cfg);
1466 st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms");
1468 for (i=0; i<st->ncomms; i++) {
1469 item_t *item=list_elem(comms_cfg,i);
1470 if (item->type!=t_closure)
1471 cfgfatal(loc,"site","comm is not a closure\n");
1472 closure_t *cl=item->data.closure;
1473 if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n");
1474 st->comms[i]=cl->interface;
1477 st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
1478 st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
1479 st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
1481 st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
1482 st->address=dict_read_string(dict, "address", False, "site", loc);
1484 st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
1485 else st->remoteport=0;
1486 st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc);
1489 find_cl_if(dict,"transform",CL_TRANSFORM,True,"site",loc);
1491 st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
1492 st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
1494 #define DEFAULT(D) (st->peer_mobile || local_mobile \
1495 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
1496 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
1498 st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
1499 st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
1500 st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
1501 st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME);
1503 st->mobile_peer_expiry= dict_read_number(
1504 dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
1506 st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number(
1507 dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX);
1508 if (st->transport_peers_max<1 ||
1509 st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) {
1510 cfgfatal(loc,"site","mobile-peers-max must be in range 1.."
1511 STRING(MAX_MOBILE_PEERS_MAX) "\n");
1514 if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
1515 st->key_renegotiate_time=st->key_lifetime/2;
1517 st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
1518 st->key_renegotiate_time=dict_read_number(
1519 dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
1520 if (st->key_renegotiate_time > st->key_lifetime) {
1521 cfgfatal(loc,"site",
1522 "renegotiate-time must be less than key-lifetime\n");
1525 st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
1526 log_event_table,"site");
1528 st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
1530 sprintf(st->tunname,"%s<->%s",st->localname,st->remotename);
1532 /* The information we expect to see in incoming messages of type 1 */
1533 /* fixme: lots of unchecked overflows here, but the results are only
1534 corrupted packets rather than undefined behaviour */
1535 st->setupsiglen=strlen(st->remotename)+strlen(st->localname)+8;
1536 st->setupsig=safe_malloc(st->setupsiglen,"site_apply");
1537 put_uint32(st->setupsig+0,LABEL_MSG1);
1538 put_uint16(st->setupsig+4,strlen(st->remotename));
1539 memcpy(&st->setupsig[6],st->remotename,strlen(st->remotename));
1540 put_uint16(st->setupsig+(6+strlen(st->remotename)),strlen(st->localname));
1541 memcpy(&st->setupsig[8+strlen(st->remotename)],st->localname,
1542 strlen(st->localname));
1543 st->setup_priority=(strcmp(st->localname,st->remotename)>0);
1545 buffer_new(&st->buffer,SETUP_BUFFER_LEN);
1547 buffer_new(&st->scratch,0);
1548 BUF_ALLOC(&st->scratch,"site:scratch");
1550 /* We are interested in poll(), but only for timeouts. We don't have
1551 any fds of our own. */
1552 register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site");
1555 st->current.key_timeout=0;
1556 st->auxiliary_key.key_timeout=0;
1557 transport_peers_clear(st,&st->peers);
1558 transport_peers_clear(st,&st->setup_peers);
1559 /* XXX mlock these */
1560 st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
1561 st->sharedsecretlen=st->transform->keylen?:st->dh->ceil_len;
1562 st->sharedsecret=safe_malloc(st->sharedsecretlen,"site:sharedsecret");
1564 /* We need to compute some properties of our comms */
1565 #define COMPUTE_WORST(pad) \
1566 int worst_##pad=0; \
1567 for (i=0; i<st->ncomms; i++) { \
1568 int thispad=st->comms[i]->pad; \
1569 if (thispad > worst_##pad) \
1570 worst_##pad=thispad; \
1572 COMPUTE_WORST(min_start_pad)
1573 COMPUTE_WORST(min_end_pad)
1575 /* We need to register the remote networks with the netlink device */
1576 st->netlink->reg(st->netlink->st, site_outgoing, st,
1577 st->transform->max_start_pad+(4*4)+
1578 worst_min_start_pad,
1579 st->transform->max_end_pad+worst_min_end_pad);
1581 for (i=0; i<st->ncomms; i++)
1582 st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
1584 st->current.transform=st->transform->create(st->transform->st);
1585 st->auxiliary_key.transform=st->transform->create(st->transform->st);
1586 st->new_transform=st->transform->create(st->transform->st);
1587 st->auxiliary_is_new=0;
1589 enter_state_stop(st);
1591 add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
1593 return new_closure(&st->cl);
1596 void site_module(dict_t *dict)
1598 add_closure(dict,"site",site_apply);
1602 /***** TRANSPORT PEERS definitions *****/
1604 static void transport_peers_debug(struct site *st, transport_peers *dst,
1605 const char *didwhat,
1606 int nargs, const struct comm_addr *args,
1611 if (!(st->log_events & LOG_PEER_ADDRS))
1612 return; /* an optimisation */
1614 slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
1615 (dst==&st->peers ? "data" :
1616 dst==&st->setup_peers ? "setup" : "UNKNOWN"),
1617 didwhat, nargs, dst->npeers);
1619 for (i=0, argp=(void*)args;
1621 i++, (argp+=stride?stride:sizeof(*args))) {
1622 const struct comm_addr *ca=(void*)argp;
1623 slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
1624 i, ca->comm->addr_to_string(ca->comm->st,ca));
1626 for (i=0; i<dst->npeers; i++) {
1627 struct timeval diff;
1628 timersub(tv_now,&dst->peers[i].last,&diff);
1629 const struct comm_addr *ca=&dst->peers[i].addr;
1630 slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
1631 i, ca->comm->addr_to_string(ca->comm->st,ca),
1632 (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
1636 static int transport_peer_compar(const void *av, const void *bv) {
1637 const transport_peer *a=av;
1638 const transport_peer *b=bv;
1639 /* put most recent first in the array */
1640 if (timercmp(&a->last, &b->last, <)) return +1;
1641 if (timercmp(&a->last, &b->last, >)) return -11;
1645 static void transport_peers_expire(struct site *st, transport_peers *peers) {
1646 /* peers must be sorted first */
1647 int previous_peers=peers->npeers;
1648 struct timeval oldest;
1649 oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
1650 oldest.tv_usec = tv_now->tv_usec;
1651 while (peers->npeers>1 &&
1652 timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
1654 if (peers->npeers != previous_peers)
1655 transport_peers_debug(st,peers,"expire", 0,0,0);
1658 static void transport_record_peer(struct site *st, transport_peers *peers,
1659 const struct comm_addr *addr, const char *m) {
1660 int slot, changed=0;
1662 for (slot=0; slot<peers->npeers; slot++)
1663 if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr)))
1667 if (peers->npeers==st->transport_peers_max)
1668 slot=st->transport_peers_max;
1670 slot=peers->npeers++;
1673 peers->peers[slot].addr=*addr;
1674 peers->peers[slot].last=*tv_now;
1676 if (peers->npeers>1)
1677 qsort(peers->peers, peers->npeers,
1678 sizeof(*peers->peers), transport_peer_compar);
1680 if (changed || peers->npeers!=1)
1681 transport_peers_debug(st,peers,m, 1,addr,0);
1682 transport_peers_expire(st, peers);
1685 static bool_t transport_compute_setupinit_peers(struct site *st,
1686 const struct comm_addr *configured_addr /* 0 if none or not found */) {
1688 if (!configured_addr && !transport_peers_valid(&st->peers))
1691 slog(st,LOG_SETUP_INIT,
1692 (!configured_addr ? "using only %d old peer address(es)"
1693 : "using configured address, and/or perhaps %d old peer address(es)"),
1696 /* Non-mobile peers havve st->peers.npeers==0 or ==1, since they
1697 * have transport_peers_max==1. The effect is that this code
1698 * always uses the configured address if supplied, or otherwise
1699 * the existing data peer if one exists; this is as desired. */
1701 transport_peers_copy(st,&st->setup_peers,&st->peers);
1703 if (configured_addr)
1704 transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit");
1706 assert(transport_peers_valid(&st->setup_peers));
1710 static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
1711 if (st->peer_mobile)
1712 transport_record_peer(st,&st->setup_peers,a,"setupmsg");
1714 static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
1715 if (st->peer_mobile)
1716 transport_record_peer(st,&st->peers,a,"datamsg");
1719 static int transport_peers_valid(transport_peers *peers) {
1720 return peers->npeers;
1722 static void transport_peers_clear(struct site *st, transport_peers *peers) {
1724 transport_peers_debug(st,peers,"clear",0,0,0);
1726 static void transport_peers_copy(struct site *st, transport_peers *dst,
1727 const transport_peers *src) {
1728 dst->npeers=src->npeers;
1729 memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers);
1730 transport_peers_debug(st,dst,"copy",
1731 src->npeers, &src->peers->addr, sizeof(*src->peers));
1734 void transport_xmit(struct site *st, transport_peers *peers,
1735 struct buffer_if *buf, bool_t candebug) {
1737 transport_peers_expire(st, peers);
1738 for (slot=0; slot<peers->npeers; slot++) {
1739 transport_peer *peer=&peers->peers[slot];
1741 dump_packet(st, buf, &peer->addr, False);
1742 peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr);
1746 /***** END of transport peers declarations *****/