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 uint32_t local_capabilities;
248 int32_t setup_retries; /* How many times to send setup packets */
249 int32_t setup_retry_interval; /* Initial timeout for setup packets */
250 int32_t wait_timeout; /* How long to wait if setup unsuccessful */
251 int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
252 int32_t key_lifetime; /* How long a key lasts once set up */
253 int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
254 after this time, initiate a new
257 bool_t setup_priority; /* Do we have precedence if both sites emit
258 message 1 simultaneously? */
261 /* runtime information */
263 uint64_t now; /* Most recently seen time */
265 /* The currently established session */
266 struct data_key current;
267 struct data_key auxiliary_key;
268 bool_t auxiliary_is_new;
269 uint64_t renegotiate_key_time; /* When we can negotiate a new key */
270 uint64_t auxiliary_renegotiate_key_time;
271 transport_peers peers; /* Current address(es) of peer for data traffic */
273 /* The current key setup protocol exchange. We can only be
274 involved in one of these at a time. There's a potential for
275 denial of service here (the attacker keeps sending a setup
276 packet; we keep trying to continue the exchange, and have to
277 timeout before we can listen for another setup packet); perhaps
278 we should keep a list of 'bad' sources for setup packets. */
279 uint32_t remote_capabilities;
280 uint32_t setup_session_id;
281 transport_peers setup_peers;
282 uint8_t localN[NONCELEN]; /* Nonces for key exchange */
283 uint8_t remoteN[NONCELEN];
284 struct buffer_if buffer; /* Current outgoing key exchange packet */
285 struct buffer_if scratch;
286 int32_t retries; /* Number of retries remaining */
287 uint64_t timeout; /* Timeout for current state */
289 uint8_t *sharedsecret;
290 uint32_t sharedsecretlen;
291 struct transform_inst_if *new_transform; /* For key setup/verify */
294 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
302 if (event&st->log_events) {
304 case LOG_UNEXPECTED: class=M_INFO; break;
305 case LOG_SETUP_INIT: class=M_INFO; break;
306 case LOG_SETUP_TIMEOUT: class=M_NOTICE; break;
307 case LOG_ACTIVATE_KEY: class=M_INFO; break;
308 case LOG_TIMEOUT_KEY: class=M_INFO; break;
309 case LOG_SEC: class=M_SECURITY; break;
310 case LOG_STATE: class=M_DEBUG; break;
311 case LOG_DROP: class=M_DEBUG; break;
312 case LOG_DUMP: class=M_DEBUG; break;
313 case LOG_ERROR: class=M_ERR; break;
314 case LOG_PEER_ADDRS: class=M_DEBUG; break;
315 default: class=M_ERR; break;
318 vsnprintf(buf,sizeof(buf),msg,ap);
319 st->log->log(st->log->st,class,"%s: %s",st->tunname,buf);
324 static void set_link_quality(struct site *st);
325 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
326 static void delete_one_key(struct site *st, struct data_key *key,
327 const char *reason /* may be 0 meaning don't log*/,
328 const char *which /* ignored if !reasonn */,
329 uint32_t loglevel /* ignored if !reasonn */);
330 static bool_t initiate_key_setup(struct site *st, cstring_t reason);
331 static void enter_state_run(struct site *st);
332 static bool_t enter_state_resolve(struct site *st);
333 static bool_t enter_new_state(struct site *st,uint32_t next);
334 static void enter_state_wait(struct site *st);
335 static void activate_new_key(struct site *st);
337 static bool_t current_valid(struct site *st)
339 return st->current.transform->valid(st->current.transform->st);
342 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
343 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
344 #define CHECK_TYPE(b,t) do { uint32_t type; \
345 CHECK_AVAIL((b),4); \
346 type=buf_unprepend_uint32((b)); \
347 if (type!=(t)) return False; } while(0)
352 struct buffer_if extrainfo;
359 struct parsedname remote;
360 struct parsedname local;
361 uint32_t remote_capabilities;
372 int32_t lenpos, afternul;
374 static void append_string_xinfo_start(struct buffer_if *buf,
375 struct xinfoadd *xia,
377 /* Helps construct one of the names with additional info as found
378 * in MSG1..4. Call this function first, then append all the
379 * desired extra info (not including the nul byte) to the buffer,
380 * then call append_string_xinfo_done. */
382 xia->lenpos = buf->size;
383 buf_append_string(buf,str);
384 buf_append_uint8(buf,0);
385 xia->afternul = buf->size;
387 static void append_string_xinfo_done(struct buffer_if *buf,
388 struct xinfoadd *xia)
390 /* we just need to adjust the string length */
391 if (buf->size == xia->afternul) {
392 /* no extra info, strip the nul too */
393 buf_unappend_uint8(buf);
395 put_uint16(buf->start+xia->lenpos, buf->size-(xia->lenpos+2));
399 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
400 out using a transform of config data supplied by netlink */
401 static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what)
407 st->retries=st->setup_retries;
408 BUF_ALLOC(&st->buffer,what);
409 buffer_init(&st->buffer,0);
410 buf_append_uint32(&st->buffer,
411 (type==LABEL_MSG1?0:st->setup_session_id));
412 buf_append_uint32(&st->buffer,st->index);
413 buf_append_uint32(&st->buffer,type);
416 append_string_xinfo_start(&st->buffer,&xia,st->localname);
417 if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
418 buf_append_uint32(&st->buffer,st->local_capabilities);
420 append_string_xinfo_done(&st->buffer,&xia);
422 buf_append_string(&st->buffer,st->remotename);
423 memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN);
424 if (type==LABEL_MSG1) return True;
425 memcpy(buf_append(&st->buffer,NONCELEN),st->remoteN,NONCELEN);
426 if (type==LABEL_MSG2) return True;
428 if (hacky_par_mid_failnow()) return False;
430 dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
431 buf_append_string(&st->buffer,dhpub);
433 hash=safe_malloc(st->hash->len, "generate_msg");
434 hst=st->hash->init();
435 st->hash->update(hst,st->buffer.start,st->buffer.size);
436 st->hash->final(hst,hash);
437 sig=st->privkey->sign(st->privkey->st,hash,st->hash->len);
438 buf_append_string(&st->buffer,sig);
444 static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
447 nm->len=buf_unprepend_uint16(msg);
448 CHECK_AVAIL(msg,nm->len);
449 nm->name=buf_unprepend(msg,nm->len);
450 uint8_t *nul=memchr(nm->name,0,nm->len);
452 buffer_readonly_view(&nm->extrainfo,0,0);
454 buffer_readonly_view(&nm->extrainfo, nul+1, msg->start-(nul+1));
455 nm->len=nul-nm->name;
460 static bool_t unpick_msg(struct site *st, uint32_t type,
461 struct buffer_if *msg, struct msg *m)
463 m->hashstart=msg->start;
465 m->dest=buf_unprepend_uint32(msg);
467 m->source=buf_unprepend_uint32(msg);
468 CHECK_TYPE(msg,type);
469 if (!unpick_name(msg,&m->remote)) return False;
470 m->remote_capabilities=0;
471 if (m->remote.extrainfo.size) {
472 CHECK_AVAIL(&m->remote.extrainfo,4);
473 m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
475 if (!unpick_name(msg,&m->local)) return False;
476 CHECK_AVAIL(msg,NONCELEN);
477 m->nR=buf_unprepend(msg,NONCELEN);
478 if (type==LABEL_MSG1) {
482 CHECK_AVAIL(msg,NONCELEN);
483 m->nL=buf_unprepend(msg,NONCELEN);
484 if (type==LABEL_MSG2) {
489 m->pklen=buf_unprepend_uint16(msg);
490 CHECK_AVAIL(msg,m->pklen);
491 m->pk=buf_unprepend(msg,m->pklen);
492 m->hashlen=msg->start-m->hashstart;
494 m->siglen=buf_unprepend_uint16(msg);
495 CHECK_AVAIL(msg,m->siglen);
496 m->sig=buf_unprepend(msg,m->siglen);
501 static bool_t name_matches(const struct parsedname *nm, const char *expected)
503 int expected_len=strlen(expected);
505 nm->len == expected_len &&
506 !memcmp(nm->name, expected, expected_len);
509 static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
512 if (type==LABEL_MSG1) return True;
514 /* Check that the site names and our nonce have been sent
515 back correctly, and then store our peer's nonce. */
516 if (!name_matches(&m->remote,st->remotename)) {
517 *error="wrong remote site name";
520 if (!name_matches(&m->local,st->localname)) {
521 *error="wrong local site name";
524 if (memcmp(m->nL,st->localN,NONCELEN)!=0) {
525 *error="wrong locally-generated nonce";
528 if (type==LABEL_MSG2) return True;
529 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
530 *error="wrong remotely-generated nonce";
533 /* MSG3 has complicated rules about capabilities, which are
534 * handled in process_msg3. */
535 if (type==LABEL_MSG3) return True;
536 if (m->remote_capabilities!=st->remote_capabilities) {
537 *error="remote capabilities changed";
540 if (type==LABEL_MSG4) return True;
541 *error="unknown message type";
545 static bool_t generate_msg1(struct site *st)
547 st->random->generate(st->random->st,NONCELEN,st->localN);
548 return generate_msg(st,LABEL_MSG1,"site:MSG1");
551 static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
552 const struct comm_addr *src, struct msg *m)
554 /* We've already determined we're in an appropriate state to
555 process an incoming MSG1, and that the MSG1 has correct values
558 transport_record_peer(st,&st->setup_peers,src,"msg1");
559 st->setup_session_id=m->source;
560 st->remote_capabilities=m->remote_capabilities;
561 memcpy(st->remoteN,m->nR,NONCELEN);
565 static bool_t generate_msg2(struct site *st)
567 st->random->generate(st->random->st,NONCELEN,st->localN);
568 return generate_msg(st,LABEL_MSG2,"site:MSG2");
571 static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
572 const struct comm_addr *src)
577 if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False;
578 if (!check_msg(st,LABEL_MSG2,&m,&err)) {
579 slog(st,LOG_SEC,"msg2: %s",err);
582 st->setup_session_id=m.source;
583 st->remote_capabilities=m.remote_capabilities;
584 memcpy(st->remoteN,m.nR,NONCELEN);
588 static bool_t generate_msg3(struct site *st)
590 /* Now we have our nonce and their nonce. Think of a secret key,
591 and create message number 3. */
592 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
593 return generate_msg(st,LABEL_MSG3,"site:MSG3");
596 static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
597 const struct comm_addr *src)
604 if (!unpick_msg(st,LABEL_MSG3,msg3,&m)) return False;
605 if (!check_msg(st,LABEL_MSG3,&m,&err)) {
606 slog(st,LOG_SEC,"msg3: %s",err);
609 uint32_t capab_adv_late = m.remote_capabilities
610 & ~st->remote_capabilities & CAPAB_EARLY;
611 if (capab_adv_late) {
612 slog(st,LOG_SEC,"msg3 impermissibly adds early capability flag(s)"
613 " %#"PRIx32" (was %#"PRIx32", now %#"PRIx32")",
614 capab_adv_late, st->remote_capabilities, m.remote_capabilities);
617 st->remote_capabilities|=m.remote_capabilities;
619 /* Check signature and store g^x mod m */
620 hash=safe_malloc(st->hash->len, "process_msg3");
621 hst=st->hash->init();
622 st->hash->update(hst,m.hashstart,m.hashlen);
623 st->hash->final(hst,hash);
624 /* Terminate signature with a '0' - cheating, but should be ok */
626 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) {
627 slog(st,LOG_SEC,"msg3 signature failed check!");
633 /* Terminate their DH public key with a '0' */
635 /* Invent our DH secret key */
636 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
638 /* Generate the shared key */
639 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk,
640 st->sharedsecret,st->sharedsecretlen);
642 /* Set up the transform */
643 st->new_transform->setkey(st->new_transform->st,st->sharedsecret,
644 st->sharedsecretlen,st->setup_priority);
649 static bool_t generate_msg4(struct site *st)
651 /* We have both nonces, their public key and our private key. Generate
652 our public key, sign it and send it to them. */
653 return generate_msg(st,LABEL_MSG4,"site:MSG4");
656 static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
657 const struct comm_addr *src)
664 if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
665 if (!check_msg(st,LABEL_MSG4,&m,&err)) {
666 slog(st,LOG_SEC,"msg4: %s",err);
670 /* Check signature and store g^x mod m */
671 hash=safe_malloc(st->hash->len, "process_msg4");
672 hst=st->hash->init();
673 st->hash->update(hst,m.hashstart,m.hashlen);
674 st->hash->final(hst,hash);
675 /* Terminate signature with a '0' - cheating, but should be ok */
677 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) {
678 slog(st,LOG_SEC,"msg4 signature failed check!");
684 /* Terminate their DH public key with a '0' */
686 /* Generate the shared key */
687 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk,
688 st->sharedsecret,st->sharedsecretlen);
689 /* Set up the transform */
690 st->new_transform->setkey(st->new_transform->st,st->sharedsecret,
691 st->sharedsecretlen,st->setup_priority);
702 static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0,
706 m->dest=buf_unprepend_uint32(msg0);
708 m->source=buf_unprepend_uint32(msg0);
710 m->type=buf_unprepend_uint32(msg0);
712 /* Leaves transformed part of buffer untouched */
715 static bool_t generate_msg5(struct site *st)
717 cstring_t transform_err;
719 BUF_ALLOC(&st->buffer,"site:MSG5");
720 /* We are going to add four words to the message */
721 buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
722 /* Give the netlink code an opportunity to put its own stuff in the
723 message (configuration information, etc.) */
724 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
725 st->new_transform->forwards(st->new_transform->st,&st->buffer,
727 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
728 buf_prepend_uint32(&st->buffer,st->index);
729 buf_prepend_uint32(&st->buffer,st->setup_session_id);
731 st->retries=st->setup_retries;
735 static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
736 const struct comm_addr *src,
737 struct transform_inst_if *transform)
740 cstring_t transform_err;
742 if (!unpick_msg0(st,msg5,&m)) return False;
744 if (transform->reverse(transform->st,msg5,&transform_err)) {
745 /* There's a problem */
746 slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
749 /* Buffer should now contain untransformed PING packet data */
751 if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) {
752 slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
755 /* Older versions of secnet used to write some config data here
756 * which we ignore. So we don't CHECK_EMPTY */
760 static void create_msg6(struct site *st, struct transform_inst_if *transform,
763 cstring_t transform_err;
765 BUF_ALLOC(&st->buffer,"site:MSG6");
766 /* We are going to add four words to the message */
767 buffer_init(&st->buffer,st->transform->max_start_pad+(4*4));
768 /* Give the netlink code an opportunity to put its own stuff in the
769 message (configuration information, etc.) */
770 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
771 transform->forwards(transform->st,&st->buffer,&transform_err);
772 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
773 buf_prepend_uint32(&st->buffer,st->index);
774 buf_prepend_uint32(&st->buffer,session_id);
777 static bool_t generate_msg6(struct site *st)
779 create_msg6(st,st->new_transform,st->setup_session_id);
780 st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
784 static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
785 const struct comm_addr *src)
788 cstring_t transform_err;
790 if (!unpick_msg0(st,msg6,&m)) return False;
792 if (st->new_transform->reverse(st->new_transform->st,
793 msg6,&transform_err)) {
794 /* There's a problem */
795 slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
798 /* Buffer should now contain untransformed PING packet data */
800 if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) {
801 slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
804 /* Older versions of secnet used to write some config data here
805 * which we ignore. So we don't CHECK_EMPTY */
809 static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
810 const struct comm_addr *src)
812 cstring_t transform_err, auxkey_err, newkey_err="n/a";
816 if (!unpick_msg0(st,msg0,&m)) return False;
818 /* Keep a copy so we can try decrypting it with multiple keys */
819 buffer_copy(&st->scratch, msg0);
821 problem = st->current.transform->reverse(st->current.transform->st,
822 msg0,&transform_err);
824 if (!st->auxiliary_is_new)
825 delete_one_key(st,&st->auxiliary_key,
826 "peer has used new key","auxiliary key",LOG_SEC);
832 buffer_copy(msg0, &st->scratch);
833 problem = st->auxiliary_key.transform->reverse
834 (st->auxiliary_key.transform->st,msg0,&auxkey_err);
836 slog(st,LOG_DROP,"processing packet which uses auxiliary key");
837 if (st->auxiliary_is_new) {
838 /* We previously timed out in state SENTMSG5 but it turns
839 * out that our peer did in fact get our MSG5 and is
840 * using the new key. So we should switch to it too. */
841 /* This is a bit like activate_new_key. */
844 st->current=st->auxiliary_key;
847 delete_one_key(st,&st->auxiliary_key,"peer has used new key",
848 "previous key",LOG_SEC);
849 st->auxiliary_is_new=0;
850 st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
857 if (st->state==SITE_SENTMSG5) {
858 buffer_copy(msg0, &st->scratch);
859 problem = st->new_transform->reverse(st->new_transform->st,
862 /* It looks like we didn't get the peer's MSG6 */
863 /* This is like a cut-down enter_new_state(SITE_RUN) */
864 slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
865 BUF_FREE(&st->buffer);
867 activate_new_key(st);
868 return True; /* do process the data in this packet */
874 slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
875 transform_err,auxkey_err,newkey_err);
876 initiate_key_setup(st,"incoming message would not decrypt");
877 send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
881 slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
885 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
886 const struct comm_addr *src)
890 if (!decrypt_msg0(st,msg0,src))
894 type=buf_unprepend_uint32(msg0);
897 /* We must forget about the current session. */
898 delete_keys(st,"request from peer",LOG_SEC);
901 /* Deliver to netlink layer */
902 st->netlink->deliver(st->netlink->st,msg0);
903 transport_data_msgok(st,src);
904 /* See whether we should start negotiating a new key */
905 if (st->now > st->renegotiate_key_time)
906 initiate_key_setup(st,"incoming packet in renegotiation window");
909 slog(st,LOG_SEC,"incoming encrypted message of type %08x "
916 static void dump_packet(struct site *st, struct buffer_if *buf,
917 const struct comm_addr *addr, bool_t incoming)
919 uint32_t dest=get_uint32(buf->start);
920 uint32_t source=get_uint32(buf->start+4);
921 uint32_t msgtype=get_uint32(buf->start+8);
923 if (st->log_events & LOG_DUMP)
924 slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x:",
925 st->tunname,incoming?"incoming":"outgoing",
926 dest,source,msgtype);
929 static uint32_t site_status(void *st)
934 static bool_t send_msg(struct site *st)
937 transport_xmit(st, &st->setup_peers, &st->buffer, True);
938 st->timeout=st->now+st->setup_retry_interval;
941 } else if (st->state==SITE_SENTMSG5) {
942 slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key");
943 /* We stash the key we have produced, in case it turns out that
944 * our peer did see our MSG5 after all and starts using it. */
945 /* This is a bit like some of activate_new_key */
946 struct transform_inst_if *t;
947 t=st->auxiliary_key.transform;
948 st->auxiliary_key.transform=st->new_transform;
952 st->auxiliary_is_new=1;
953 st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
954 st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
955 st->auxiliary_key.remote_session_id=st->setup_session_id;
957 enter_state_wait(st);
960 slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet "
961 "(in state %s)",state_name(st->state));
962 enter_state_wait(st);
967 static void site_resolve_callback(void *sst, struct in_addr *address)
970 struct comm_addr ca_buf, *ca_use;
972 if (st->state!=SITE_RESOLVE) {
973 slog(st,LOG_UNEXPECTED,"site_resolve_callback called unexpectedly");
978 ca_buf.comm=st->comms[0];
979 ca_buf.sin.sin_family=AF_INET;
980 ca_buf.sin.sin_port=htons(st->remoteport);
981 ca_buf.sin.sin_addr=*address;
984 slog(st,LOG_ERROR,"resolution of %s failed",st->address);
987 if (transport_compute_setupinit_peers(st,ca_use)) {
988 enter_new_state(st,SITE_SENTMSG1);
990 /* Can't figure out who to try to to talk to */
991 slog(st,LOG_SETUP_INIT,"key exchange failed: cannot find peer address");
996 static bool_t initiate_key_setup(struct site *st, cstring_t reason)
998 if (st->state!=SITE_RUN) return False;
999 slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
1001 slog(st,LOG_SETUP_INIT,"resolving peer address");
1002 return enter_state_resolve(st);
1003 } else if (transport_compute_setupinit_peers(st,0)) {
1004 return enter_new_state(st,SITE_SENTMSG1);
1006 slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
1010 static void activate_new_key(struct site *st)
1012 struct transform_inst_if *t;
1014 /* We have three transform instances, which we swap between old,
1016 t=st->auxiliary_key.transform;
1017 st->auxiliary_key.transform=st->current.transform;
1018 st->current.transform=st->new_transform;
1019 st->new_transform=t;
1023 st->auxiliary_is_new=0;
1024 st->auxiliary_key.key_timeout=st->current.key_timeout;
1025 st->current.key_timeout=st->now+st->key_lifetime;
1026 st->renegotiate_key_time=st->now+st->key_renegotiate_time;
1027 transport_peers_copy(st,&st->peers,&st->setup_peers);
1028 st->current.remote_session_id=st->setup_session_id;
1030 slog(st,LOG_ACTIVATE_KEY,"new key activated");
1031 enter_state_run(st);
1034 static void delete_one_key(struct site *st, struct data_key *key,
1035 cstring_t reason, cstring_t which, uint32_t loglevel)
1037 if (!key->transform->valid(key->transform->st)) return;
1038 if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
1039 key->transform->delkey(key->transform->st);
1043 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
1045 if (current_valid(st)) {
1046 slog(st,loglevel,"session closed (%s)",reason);
1048 delete_one_key(st,&st->current,0,0,0);
1049 set_link_quality(st);
1051 delete_one_key(st,&st->auxiliary_key,0,0,0);
1054 static void state_assert(struct site *st, bool_t ok)
1056 if (!ok) fatal("site:state_assert");
1059 static void enter_state_stop(struct site *st)
1061 st->state=SITE_STOP;
1063 delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
1064 st->new_transform->delkey(st->new_transform->st);
1067 static void set_link_quality(struct site *st)
1070 if (current_valid(st))
1071 quality=LINK_QUALITY_UP;
1072 else if (st->state==SITE_WAIT || st->state==SITE_STOP)
1073 quality=LINK_QUALITY_DOWN;
1074 else if (st->address)
1075 quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
1076 else if (transport_peers_valid(&st->peers))
1077 quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
1079 quality=LINK_QUALITY_DOWN;
1081 st->netlink->set_quality(st->netlink->st,quality);
1084 static void enter_state_run(struct site *st)
1086 slog(st,LOG_STATE,"entering state RUN");
1090 st->setup_session_id=0;
1091 transport_peers_clear(st,&st->setup_peers);
1092 memset(st->localN,0,NONCELEN);
1093 memset(st->remoteN,0,NONCELEN);
1094 st->new_transform->delkey(st->new_transform->st);
1095 memset(st->dhsecret,0,st->dh->len);
1096 memset(st->sharedsecret,0,st->sharedsecretlen);
1097 set_link_quality(st);
1100 static bool_t enter_state_resolve(struct site *st)
1102 state_assert(st,st->state==SITE_RUN);
1103 slog(st,LOG_STATE,"entering state RESOLVE");
1104 st->state=SITE_RESOLVE;
1105 st->resolver->request(st->resolver->st,st->address,
1106 site_resolve_callback,st);
1110 static bool_t enter_new_state(struct site *st, uint32_t next)
1112 bool_t (*gen)(struct site *st);
1115 slog(st,LOG_STATE,"entering state %s",state_name(next));
1118 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
1122 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1123 st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
1127 state_assert(st,st->state==SITE_SENTMSG1);
1128 BUF_FREE(&st->buffer);
1132 state_assert(st,st->state==SITE_SENTMSG2);
1133 BUF_FREE(&st->buffer);
1137 state_assert(st,st->state==SITE_SENTMSG3);
1138 BUF_FREE(&st->buffer);
1142 state_assert(st,st->state==SITE_SENTMSG4);
1143 BUF_FREE(&st->buffer);
1148 fatal("enter_new_state(%s): invalid new state",state_name(next));
1152 if (hacky_par_start_failnow()) return False;
1154 r= gen(st) && send_msg(st);
1157 st->setup_retries, st->setup_retry_interval,
1162 if (next==SITE_RUN) {
1163 BUF_FREE(&st->buffer); /* Never reused */
1164 st->timeout=0; /* Never retransmit */
1165 activate_new_key(st);
1169 slog(st,LOG_ERROR,"error entering state %s",state_name(next));
1170 st->buffer.free=False; /* Unconditionally use the buffer; it may be
1171 in either state, and enter_state_wait() will
1173 enter_state_wait(st);
1177 /* msg7 tells our peer that we're about to forget our key */
1178 static bool_t send_msg7(struct site *st, cstring_t reason)
1180 cstring_t transform_err;
1182 if (current_valid(st) && st->buffer.free
1183 && transport_peers_valid(&st->peers)) {
1184 BUF_ALLOC(&st->buffer,"site:MSG7");
1185 buffer_init(&st->buffer,st->transform->max_start_pad+(4*3));
1186 buf_append_uint32(&st->buffer,LABEL_MSG7);
1187 buf_append_string(&st->buffer,reason);
1188 st->current.transform->forwards(st->current.transform->st,
1189 &st->buffer, &transform_err);
1190 buf_prepend_uint32(&st->buffer,LABEL_MSG0);
1191 buf_prepend_uint32(&st->buffer,st->index);
1192 buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
1193 transport_xmit(st,&st->peers,&st->buffer,True);
1194 BUF_FREE(&st->buffer);
1200 /* We go into this state if our peer becomes uncommunicative. Similar to
1201 the "stop" state, we forget all session keys for a while, before
1202 re-entering the "run" state. */
1203 static void enter_state_wait(struct site *st)
1205 slog(st,LOG_STATE,"entering state WAIT");
1206 st->timeout=st->now+st->wait_timeout;
1207 st->state=SITE_WAIT;
1208 set_link_quality(st);
1209 BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
1210 /* XXX Erase keys etc. */
1213 static inline void site_settimeout(uint64_t timeout, int *timeout_io)
1216 int64_t offset=timeout-*now;
1217 if (offset<0) offset=0;
1218 if (offset>INT_MAX) offset=INT_MAX;
1219 if (*timeout_io<0 || offset<*timeout_io)
1224 static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
1227 struct site *st=sst;
1229 *nfds_io=0; /* We don't use any file descriptors */
1232 /* Work out when our next timeout is. The earlier of 'timeout' or
1233 'current.key_timeout'. A stored value of '0' indicates no timeout
1235 site_settimeout(st->timeout, timeout_io);
1236 site_settimeout(st->current.key_timeout, timeout_io);
1237 site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
1239 return 0; /* success */
1242 static void check_expiry(struct site *st, struct data_key *key,
1245 if (key->key_timeout && *now>key->key_timeout) {
1246 delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
1250 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1251 static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
1253 struct site *st=sst;
1256 if (st->timeout && *now>st->timeout) {
1258 if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) {
1259 if (!hacky_par_start_failnow())
1261 } else if (st->state==SITE_WAIT) {
1262 enter_state_run(st);
1264 slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d",
1268 check_expiry(st,&st->current,"current key");
1269 check_expiry(st,&st->auxiliary_key,"auxiliary key");
1272 /* This function is called by the netlink device to deliver packets
1273 intended for the remote network. The packet is in "raw" wire
1274 format, but is guaranteed to be word-aligned. */
1275 static void site_outgoing(void *sst, struct buffer_if *buf)
1277 struct site *st=sst;
1278 cstring_t transform_err;
1280 if (st->state==SITE_STOP) {
1285 /* In all other states we consider delivering the packet if we have
1286 a valid key and a valid address to send it to. */
1287 if (current_valid(st) && transport_peers_valid(&st->peers)) {
1288 /* Transform it and send it */
1290 buf_prepend_uint32(buf,LABEL_MSG9);
1291 st->current.transform->forwards(st->current.transform->st,
1292 buf, &transform_err);
1293 buf_prepend_uint32(buf,LABEL_MSG0);
1294 buf_prepend_uint32(buf,st->index);
1295 buf_prepend_uint32(buf,st->current.remote_session_id);
1296 transport_xmit(st,&st->peers,buf,False);
1302 slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size);
1304 initiate_key_setup(st,"outgoing packet");
1307 static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
1308 uint32_t type, struct msg *m)
1309 /* For packets which are identified by the local and remote names.
1310 * If it has our name and our peer's name in it it's for us. */
1312 struct buffer_if buf[1];
1313 buffer_readonly_clone(buf,buf_in);
1314 return unpick_msg(st,type,buf,m)
1315 && name_matches(&m->remote,st->remotename)
1316 && name_matches(&m->local,st->localname);
1319 /* This function is called by the communication device to deliver
1320 packets from our peers. */
1321 static bool_t site_incoming(void *sst, struct buffer_if *buf,
1322 const struct comm_addr *source)
1324 struct site *st=sst;
1326 if (buf->size < 12) return False;
1328 uint32_t dest=get_uint32(buf->start);
1329 uint32_t msgtype=get_uint32(buf->start+8);
1330 struct msg named_msg;
1332 if (msgtype==LABEL_MSG1) {
1333 if (!named_for_us(st,buf,msgtype,&named_msg))
1335 /* It's a MSG1 addressed to us. Decide what to do about it. */
1336 dump_packet(st,buf,source,True);
1337 if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1338 st->state==SITE_WAIT) {
1339 /* We should definitely process it */
1340 if (process_msg1(st,buf,source,&named_msg)) {
1341 slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
1342 enter_new_state(st,SITE_SENTMSG2);
1344 slog(st,LOG_ERROR,"failed to process incoming msg1");
1348 } else if (st->state==SITE_SENTMSG1) {
1349 /* We've just sent a message 1! They may have crossed on
1350 the wire. If we have priority then we ignore the
1351 incoming one, otherwise we process it as usual. */
1352 if (st->setup_priority) {
1354 slog(st,LOG_DUMP,"crossed msg1s; we are higher "
1355 "priority => ignore incoming msg1");
1358 slog(st,LOG_DUMP,"crossed msg1s; we are lower "
1359 "priority => use incoming msg1");
1360 if (process_msg1(st,buf,source,&named_msg)) {
1361 BUF_FREE(&st->buffer); /* Free our old message 1 */
1362 enter_new_state(st,SITE_SENTMSG2);
1364 slog(st,LOG_ERROR,"failed to process an incoming "
1365 "crossed msg1 (we have low priority)");
1371 /* The message 1 was received at an unexpected stage of the
1372 key setup. XXX POLICY - what do we do? */
1373 slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
1377 if (dest==st->index) {
1378 /* Explicitly addressed to us */
1379 if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True);
1382 /* If the source is our current peer then initiate a key setup,
1383 because our peer's forgotten the key */
1384 if (get_uint32(buf->start+4)==st->current.remote_session_id) {
1385 initiate_key_setup(st,"received a NAK");
1387 slog(st,LOG_SEC,"bad incoming NAK");
1391 process_msg0(st,buf,source);
1394 /* Setup packet: should not have been explicitly addressed
1396 slog(st,LOG_SEC,"incoming explicitly addressed msg1");
1399 /* Setup packet: expected only in state SENTMSG1 */
1400 if (st->state!=SITE_SENTMSG1) {
1401 slog(st,LOG_UNEXPECTED,"unexpected MSG2");
1402 } else if (process_msg2(st,buf,source)) {
1403 transport_setup_msgok(st,source);
1404 enter_new_state(st,SITE_SENTMSG3);
1406 slog(st,LOG_SEC,"invalid MSG2");
1410 /* Setup packet: expected only in state SENTMSG2 */
1411 if (st->state!=SITE_SENTMSG2) {
1412 slog(st,LOG_UNEXPECTED,"unexpected MSG3");
1413 } else if (process_msg3(st,buf,source)) {
1414 transport_setup_msgok(st,source);
1415 enter_new_state(st,SITE_SENTMSG4);
1417 slog(st,LOG_SEC,"invalid MSG3");
1421 /* Setup packet: expected only in state SENTMSG3 */
1422 if (st->state!=SITE_SENTMSG3) {
1423 slog(st,LOG_UNEXPECTED,"unexpected MSG4");
1424 } else if (process_msg4(st,buf,source)) {
1425 transport_setup_msgok(st,source);
1426 enter_new_state(st,SITE_SENTMSG5);
1428 slog(st,LOG_SEC,"invalid MSG4");
1432 /* Setup packet: expected only in state SENTMSG4 */
1433 /* (may turn up in state RUN if our return MSG6 was lost
1434 and the new key has already been activated. In that
1435 case we discard it. The peer will realise that we
1436 are using the new key when they see our data packets.
1437 Until then the peer's data packets to us get discarded. */
1438 if (st->state==SITE_SENTMSG4) {
1439 if (process_msg5(st,buf,source,st->new_transform)) {
1440 transport_setup_msgok(st,source);
1441 enter_new_state(st,SITE_RUN);
1443 slog(st,LOG_SEC,"invalid MSG5");
1445 } else if (st->state==SITE_RUN) {
1446 if (process_msg5(st,buf,source,st->current.transform)) {
1447 slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
1448 transport_setup_msgok(st,source);
1449 create_msg6(st,st->current.transform,
1450 st->current.remote_session_id);
1451 transport_xmit(st,&st->peers,&st->buffer,True);
1452 BUF_FREE(&st->buffer);
1454 slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
1457 slog(st,LOG_UNEXPECTED,"unexpected MSG5");
1461 /* Setup packet: expected only in state SENTMSG5 */
1462 if (st->state!=SITE_SENTMSG5) {
1463 slog(st,LOG_UNEXPECTED,"unexpected MSG6");
1464 } else if (process_msg6(st,buf,source)) {
1465 BUF_FREE(&st->buffer); /* Free message 5 */
1466 transport_setup_msgok(st,source);
1467 activate_new_key(st);
1469 slog(st,LOG_SEC,"invalid MSG6");
1473 slog(st,LOG_SEC,"received message of unknown type 0x%08x",
1484 static void site_control(void *vst, bool_t run)
1486 struct site *st=vst;
1487 if (run) enter_state_run(st);
1488 else enter_state_stop(st);
1491 static void site_phase_hook(void *sst, uint32_t newphase)
1493 struct site *st=sst;
1495 /* The program is shutting down; tell our peer */
1496 send_msg7(st,"shutting down");
1499 static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
1502 static uint32_t index_sequence;
1508 st=safe_malloc(sizeof(*st),"site_apply");
1510 st->cl.description="site";
1511 st->cl.type=CL_SITE;
1513 st->cl.interface=&st->ops;
1515 st->ops.control=site_control;
1516 st->ops.status=site_status;
1518 /* First parameter must be a dict */
1519 item=list_elem(args,0);
1520 if (!item || item->type!=t_dict)
1521 cfgfatal(loc,"site","parameter must be a dictionary\n");
1523 dict=item->data.dict;
1524 st->localname=dict_read_string(dict, "local-name", True, "site", loc);
1525 st->remotename=dict_read_string(dict, "name", True, "site", loc);
1527 st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
1528 bool_t local_mobile=
1529 dict_read_bool(dict,"local-mobile",False,"site",loc,False);
1531 /* Sanity check (which also allows the 'sites' file to include
1532 site() closures for all sites including our own): refuse to
1533 talk to ourselves */
1534 if (strcmp(st->localname,st->remotename)==0) {
1535 Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
1537 if (st->peer_mobile != local_mobile)
1538 cfgfatal(loc,"site","site %s's peer-mobile=%d"
1539 " but our local-mobile=%d\n",
1540 st->localname, st->peer_mobile, local_mobile);
1544 if (st->peer_mobile && local_mobile) {
1545 Message(M_WARNING,"site %s: site is mobile but so are we"
1546 " -> ignoring this site\n", st->remotename);
1551 assert(index_sequence < 0xffffffffUL);
1552 st->index = ++index_sequence;
1553 st->local_capabilities = 0;
1554 st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
1556 list_t *comms_cfg=dict_lookup(dict,"comm");
1557 if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n");
1558 st->ncomms=list_length(comms_cfg);
1559 st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms");
1561 for (i=0; i<st->ncomms; i++) {
1562 item_t *item=list_elem(comms_cfg,i);
1563 if (item->type!=t_closure)
1564 cfgfatal(loc,"site","comm is not a closure\n");
1565 closure_t *cl=item->data.closure;
1566 if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n");
1567 st->comms[i]=cl->interface;
1570 st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
1571 st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
1572 st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
1574 st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
1575 st->address=dict_read_string(dict, "address", False, "site", loc);
1577 st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
1578 else st->remoteport=0;
1579 st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc);
1582 find_cl_if(dict,"transform",CL_TRANSFORM,True,"site",loc);
1584 st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
1585 st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
1587 #define DEFAULT(D) (st->peer_mobile || local_mobile \
1588 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
1589 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
1591 st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
1592 st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
1593 st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
1594 st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME);
1596 st->mobile_peer_expiry= dict_read_number(
1597 dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
1599 st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number(
1600 dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX);
1601 if (st->transport_peers_max<1 ||
1602 st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) {
1603 cfgfatal(loc,"site","mobile-peers-max must be in range 1.."
1604 STRING(MAX_MOBILE_PEERS_MAX) "\n");
1607 if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
1608 st->key_renegotiate_time=st->key_lifetime/2;
1610 st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
1611 st->key_renegotiate_time=dict_read_number(
1612 dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
1613 if (st->key_renegotiate_time > st->key_lifetime) {
1614 cfgfatal(loc,"site",
1615 "renegotiate-time must be less than key-lifetime\n");
1618 st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
1619 log_event_table,"site");
1621 st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
1623 sprintf(st->tunname,"%s<->%s",st->localname,st->remotename);
1625 /* The information we expect to see in incoming messages of type 1 */
1626 /* fixme: lots of unchecked overflows here, but the results are only
1627 corrupted packets rather than undefined behaviour */
1628 st->setup_priority=(strcmp(st->localname,st->remotename)>0);
1630 buffer_new(&st->buffer,SETUP_BUFFER_LEN);
1632 buffer_new(&st->scratch,0);
1633 BUF_ALLOC(&st->scratch,"site:scratch");
1635 /* We are interested in poll(), but only for timeouts. We don't have
1636 any fds of our own. */
1637 register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site");
1640 st->remote_capabilities=0;
1641 st->current.key_timeout=0;
1642 st->auxiliary_key.key_timeout=0;
1643 transport_peers_clear(st,&st->peers);
1644 transport_peers_clear(st,&st->setup_peers);
1645 /* XXX mlock these */
1646 st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
1647 st->sharedsecretlen=st->transform->keylen?:st->dh->ceil_len;
1648 st->sharedsecret=safe_malloc(st->sharedsecretlen,"site:sharedsecret");
1650 /* We need to compute some properties of our comms */
1651 #define COMPUTE_WORST(pad) \
1652 int worst_##pad=0; \
1653 for (i=0; i<st->ncomms; i++) { \
1654 int thispad=st->comms[i]->pad; \
1655 if (thispad > worst_##pad) \
1656 worst_##pad=thispad; \
1658 COMPUTE_WORST(min_start_pad)
1659 COMPUTE_WORST(min_end_pad)
1661 /* We need to register the remote networks with the netlink device */
1662 st->netlink->reg(st->netlink->st, site_outgoing, st,
1663 st->transform->max_start_pad+(4*4)+
1664 worst_min_start_pad,
1665 st->transform->max_end_pad+worst_min_end_pad);
1667 for (i=0; i<st->ncomms; i++)
1668 st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
1670 st->current.transform=st->transform->create(st->transform->st);
1671 st->auxiliary_key.transform=st->transform->create(st->transform->st);
1672 st->new_transform=st->transform->create(st->transform->st);
1673 st->auxiliary_is_new=0;
1675 enter_state_stop(st);
1677 add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
1679 return new_closure(&st->cl);
1682 void site_module(dict_t *dict)
1684 add_closure(dict,"site",site_apply);
1688 /***** TRANSPORT PEERS definitions *****/
1690 static void transport_peers_debug(struct site *st, transport_peers *dst,
1691 const char *didwhat,
1692 int nargs, const struct comm_addr *args,
1697 if (!(st->log_events & LOG_PEER_ADDRS))
1698 return; /* an optimisation */
1700 slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
1701 (dst==&st->peers ? "data" :
1702 dst==&st->setup_peers ? "setup" : "UNKNOWN"),
1703 didwhat, nargs, dst->npeers);
1705 for (i=0, argp=(void*)args;
1707 i++, (argp+=stride?stride:sizeof(*args))) {
1708 const struct comm_addr *ca=(void*)argp;
1709 slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
1710 i, ca->comm->addr_to_string(ca->comm->st,ca));
1712 for (i=0; i<dst->npeers; i++) {
1713 struct timeval diff;
1714 timersub(tv_now,&dst->peers[i].last,&diff);
1715 const struct comm_addr *ca=&dst->peers[i].addr;
1716 slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
1717 i, ca->comm->addr_to_string(ca->comm->st,ca),
1718 (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
1722 static int transport_peer_compar(const void *av, const void *bv) {
1723 const transport_peer *a=av;
1724 const transport_peer *b=bv;
1725 /* put most recent first in the array */
1726 if (timercmp(&a->last, &b->last, <)) return +1;
1727 if (timercmp(&a->last, &b->last, >)) return -11;
1731 static void transport_peers_expire(struct site *st, transport_peers *peers) {
1732 /* peers must be sorted first */
1733 int previous_peers=peers->npeers;
1734 struct timeval oldest;
1735 oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
1736 oldest.tv_usec = tv_now->tv_usec;
1737 while (peers->npeers>1 &&
1738 timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
1740 if (peers->npeers != previous_peers)
1741 transport_peers_debug(st,peers,"expire", 0,0,0);
1744 static void transport_record_peer(struct site *st, transport_peers *peers,
1745 const struct comm_addr *addr, const char *m) {
1746 int slot, changed=0;
1748 for (slot=0; slot<peers->npeers; slot++)
1749 if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr)))
1753 if (peers->npeers==st->transport_peers_max)
1754 slot=st->transport_peers_max;
1756 slot=peers->npeers++;
1759 peers->peers[slot].addr=*addr;
1760 peers->peers[slot].last=*tv_now;
1762 if (peers->npeers>1)
1763 qsort(peers->peers, peers->npeers,
1764 sizeof(*peers->peers), transport_peer_compar);
1766 if (changed || peers->npeers!=1)
1767 transport_peers_debug(st,peers,m, 1,addr,0);
1768 transport_peers_expire(st, peers);
1771 static bool_t transport_compute_setupinit_peers(struct site *st,
1772 const struct comm_addr *configured_addr /* 0 if none or not found */) {
1774 if (!configured_addr && !transport_peers_valid(&st->peers))
1777 slog(st,LOG_SETUP_INIT,
1778 (!configured_addr ? "using only %d old peer address(es)"
1779 : "using configured address, and/or perhaps %d old peer address(es)"),
1782 /* Non-mobile peers havve st->peers.npeers==0 or ==1, since they
1783 * have transport_peers_max==1. The effect is that this code
1784 * always uses the configured address if supplied, or otherwise
1785 * the existing data peer if one exists; this is as desired. */
1787 transport_peers_copy(st,&st->setup_peers,&st->peers);
1789 if (configured_addr)
1790 transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit");
1792 assert(transport_peers_valid(&st->setup_peers));
1796 static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
1797 if (st->peer_mobile)
1798 transport_record_peer(st,&st->setup_peers,a,"setupmsg");
1800 static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
1801 if (st->peer_mobile)
1802 transport_record_peer(st,&st->peers,a,"datamsg");
1805 static int transport_peers_valid(transport_peers *peers) {
1806 return peers->npeers;
1808 static void transport_peers_clear(struct site *st, transport_peers *peers) {
1810 transport_peers_debug(st,peers,"clear",0,0,0);
1812 static void transport_peers_copy(struct site *st, transport_peers *dst,
1813 const transport_peers *src) {
1814 dst->npeers=src->npeers;
1815 memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers);
1816 transport_peers_debug(st,dst,"copy",
1817 src->npeers, &src->peers->addr, sizeof(*src->peers));
1820 void transport_xmit(struct site *st, transport_peers *peers,
1821 struct buffer_if *buf, bool_t candebug) {
1823 transport_peers_expire(st, peers);
1824 for (slot=0; slot<peers->npeers; slot++) {
1825 transport_peer *peer=&peers->peers[slot];
1827 dump_packet(st, buf, &peer->addr, False);
1828 peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr);
1832 /***** END of transport peers declarations *****/