1 /* site.c - manage communication with a remote network site */
4 * This file is part of secnet.
5 * See README for full list of copyright holders.
7 * secnet is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version d of the License, or
10 * (at your option) any later version.
12 * secnet is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * version 3 along with secnet; if not, see
19 * https://www.gnu.org/licenses/gpl.html.
22 /* The 'site' code doesn't know anything about the structure of the
23 packets it's transmitting. In fact, under the new netlink
24 configuration scheme it doesn't need to know anything at all about
25 IP addresses, except how to contact its peer. This means it could
26 potentially be used to tunnel other protocols too (IPv6, IPX, plain
27 old Ethernet frames) if appropriate netlink code can be written
28 (and that ought not to be too hard, eg. using the TUN/TAP device to
29 pretend to be an Ethernet interface). */
31 /* At some point in the future the netlink code will be asked for
32 configuration information to go in the PING/PONG packets at the end
33 of the key exchange. */
40 #include <sys/socket.h>
44 #include "unaligned.h"
47 #define SETUP_BUFFER_LEN 2048
49 #define DEFAULT_KEY_LIFETIME (3600*1000) /* [ms] */
50 #define DEFAULT_KEY_RENEGOTIATE_GAP (5*60*1000) /* [ms] */
51 #define DEFAULT_SETUP_RETRIES 5
52 #define DEFAULT_SETUP_RETRY_INTERVAL (2*1000) /* [ms] */
53 #define DEFAULT_WAIT_TIME (20*1000) /* [ms] */
55 #define DEFAULT_MOBILE_KEY_LIFETIME (2*24*3600*1000) /* [ms] */
56 #define DEFAULT_MOBILE_KEY_RENEGOTIATE_GAP (12*3600*1000) /* [ms] */
57 #define DEFAULT_MOBILE_SETUP_RETRIES 30
58 #define DEFAULT_MOBILE_SETUP_RETRY_INTERVAL (1*1000) /* [ms] */
59 #define DEFAULT_MOBILE_WAIT_TIME (10*1000) /* [ms] */
61 #define DEFAULT_MOBILE_PEER_EXPIRY (2*60) /* [s] */
63 /* Each site can be in one of several possible states. */
66 SITE_STOP - nothing is allowed to happen; tunnel is down;
67 all session keys have been erased
68 -> SITE_RUN upon external instruction
69 SITE_RUN - site up, maybe with valid key
70 -> SITE_RESOLVE upon outgoing packet and no valid key
71 we start name resolution for the other end of the tunnel
72 -> SITE_SENTMSG2 upon valid incoming message 1 and suitable time
73 we send an appropriate message 2
74 SITE_RESOLVE - waiting for name resolution
75 -> SITE_SENTMSG1 upon successful resolution
76 we send an appropriate message 1
77 -> SITE_SENTMSG2 upon valid incoming message 1 (then abort resolution)
78 we abort resolution and
79 -> SITE_WAIT on timeout or resolution failure
81 -> SITE_SENTMSG2 upon valid incoming message 1 from higher priority end
82 -> SITE_SENTMSG3 upon valid incoming message 2
83 -> SITE_WAIT on timeout
85 -> SITE_SENTMSG4 upon valid incoming message 3
86 -> SITE_WAIT on timeout
88 -> SITE_SENTMSG5 upon valid incoming message 4
89 -> SITE_WAIT on timeout
91 -> SITE_RUN upon valid incoming message 5
92 -> SITE_WAIT on timeout
94 -> SITE_RUN upon valid incoming message 6
95 -> SITE_WAIT on timeout
96 SITE_WAIT - failed to establish key; do nothing for a while
97 -> SITE_RUN on timeout
102 #define SITE_RESOLVE 2
103 #define SITE_SENTMSG1 3
104 #define SITE_SENTMSG2 4
105 #define SITE_SENTMSG3 5
106 #define SITE_SENTMSG4 6
107 #define SITE_SENTMSG5 7
110 int32_t site_max_start_pad = 4*4;
112 static cstring_t state_name(uint32_t state)
115 case 0: return "STOP";
116 case 1: return "RUN";
117 case 2: return "RESOLVE";
118 case 3: return "SENTMSG1";
119 case 4: return "SENTMSG2";
120 case 5: return "SENTMSG3";
121 case 6: return "SENTMSG4";
122 case 7: return "SENTMSG5";
123 case 8: return "WAIT";
124 default: return "*bad state*";
130 #define LOG_UNEXPECTED 0x00000001
131 #define LOG_SETUP_INIT 0x00000002
132 #define LOG_SETUP_TIMEOUT 0x00000004
133 #define LOG_ACTIVATE_KEY 0x00000008
134 #define LOG_TIMEOUT_KEY 0x00000010
135 #define LOG_SEC 0x00000020
136 #define LOG_STATE 0x00000040
137 #define LOG_DROP 0x00000080
138 #define LOG_DUMP 0x00000100
139 #define LOG_ERROR 0x00000400
140 #define LOG_PEER_ADDRS 0x00000800
142 static struct flagstr log_event_table[]={
143 { "unexpected", LOG_UNEXPECTED },
144 { "setup-init", LOG_SETUP_INIT },
145 { "setup-timeout", LOG_SETUP_TIMEOUT },
146 { "activate-key", LOG_ACTIVATE_KEY },
147 { "timeout-key", LOG_TIMEOUT_KEY },
148 { "security", LOG_SEC },
149 { "state-change", LOG_STATE },
150 { "packet-drop", LOG_DROP },
151 { "dump-packets", LOG_DUMP },
152 { "errors", LOG_ERROR },
153 { "peer-addrs", LOG_PEER_ADDRS },
154 { "default", LOG_SETUP_INIT|LOG_SETUP_TIMEOUT|
155 LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR },
156 { "all", 0xffffffff },
161 /***** TRANSPORT PEERS declarations *****/
163 /* Details of "mobile peer" semantics:
165 - We use the same data structure for the different configurations,
166 but manage it with different algorithms.
168 - We record up to mobile_peers_max peer address/port numbers
169 ("peers") for key setup, and separately up to mobile_peers_max
172 - In general, we make a new set of addrs (see below) when we start
173 a new key exchange; the key setup addrs become the data transport
174 addrs when key setup complets.
176 If our peer is mobile:
178 - We send to all recent addresses of incoming packets, plus
179 initially all configured addresses (which we also expire).
181 - So, we record addrs of good incoming packets, as follows:
182 1. expire any peers last seen >120s ("mobile-peer-expiry") ago
183 2. add the peer of the just received packet to the applicable list
184 (possibly evicting the oldest entries to make room)
185 NB that we do not expire peers until an incoming packet arrives.
187 - If the peer has a configured address or name, we record them the
188 same way, but only as a result of our own initiation of key
189 setup. (We might evict some incoming packet addrs to make room.)
191 - The default number of addrs to keep is 3, or 4 if we have a
192 configured name or address. That's space for two configured
193 addresses (one IPv6 and one IPv4), plus two received addresses.
195 - Outgoing packets are sent to every recorded address in the
196 applicable list. Any unsupported[1] addresses are deleted from
197 the list right away. (This should only happen to configured
198 addresses, of course, but there is no need to check that.)
200 - When we successfully complete a key setup, we merge the key setup
201 peers into the data transfer peers.
203 [1] An unsupported address is one for whose AF we don't have a
204 socket (perhaps because we got EAFNOSUPPORT or some such) or for
205 which sendto gives ENETUNREACH.
207 If neither end is mobile:
209 - When peer initiated the key exchange, we use the incoming packet
212 - When we initiate the key exchange, we try configured addresses
213 until we get one which isn't unsupported then fixate on that.
215 - When we complete a key setup, we replace the data transport peers
216 with those from the key setup.
220 - We can't tell when local network setup changes so we can't cache
221 the unsupported addrs and completely remove the spurious calls to
222 sendto, but we can optimise things a bit by deprioritising addrs
223 which seem to be unsupported.
225 - Use only configured addresses. (Except, that if our peer
226 initiated a key exchange we use the incoming packet address until
227 our name resolution completes.)
229 - When we send a packet, try each address in turn; if addr
230 supported, put that address to the end of the list for future
231 packets, and go onto the next address.
233 - When we complete a key setup, we replace the data transport peers
234 with those from the key setup.
240 struct comm_addr addr;
244 /* configuration information */
245 /* runtime information */
247 transport_peer peers[MAX_PEER_ADDRS];
250 /* Basic operations on transport peer address sets */
251 static void transport_peers_clear(struct site *st, transport_peers *peers);
252 static int transport_peers_valid(transport_peers *peers);
253 static void transport_peers_copy(struct site *st, transport_peers *dst,
254 const transport_peers *src);
256 /* Record address of incoming setup packet; resp. data packet. */
257 static void transport_setup_msgok(struct site *st, const struct comm_addr *a);
258 static void transport_data_msgok(struct site *st, const struct comm_addr *a);
260 /* Initialise the setup addresses. Called before we send the first
261 * packet in a key exchange. If we are the initiator, as a result of
262 * resolve completing (or being determined not to be relevant) or an
263 * incoming PROD; if we are the responder, as a result of the MSG1. */
264 static bool_t transport_compute_setupinit_peers(struct site *st,
265 const struct comm_addr *configured_addrs /* 0 if none or not found */,
266 int n_configured_addrs /* 0 if none or not found */,
267 const struct comm_addr *incoming_packet_addr /* 0 if none */);
269 /* Called if we are the responder in a key setup, when the resolve
270 * completes. transport_compute_setupinit_peers will hvae been called
271 * earlier. If _complete is called, we are still doing the key setup
272 * (and we should use the new values for both the rest of the key
273 * setup and the ongoing data exchange); if _tardy is called, the key
274 * setup is done (either completed or not) and only the data peers are
276 static void transport_resolve_complete(struct site *st,
277 const struct comm_addr *addrs, int naddrs);
278 static void transport_resolve_complete_tardy(struct site *st,
279 const struct comm_addr *addrs, int naddrs);
281 static void transport_xmit(struct site *st, transport_peers *peers,
282 struct buffer_if *buf, bool_t candebug);
284 /***** END of transport peers declarations *****/
288 struct transform_inst_if *transform;
289 uint64_t key_timeout; /* End of life of current key */
290 uint32_t remote_session_id;
296 /* configuration information */
299 bool_t local_mobile, peer_mobile; /* Mobile client support */
300 int32_t transport_peers_max;
301 string_t tunname; /* localname<->remotename by default, used in logs */
302 cstring_t *addresses; /* DNS name or address(es) for bootstrapping, optional */
303 int remoteport; /* Port for bootstrapping, optional */
305 struct netlink_if *netlink;
306 struct comm_if **comms;
308 struct resolver_if *resolver;
310 struct random_if *random;
311 struct rsaprivkey_if *privkey;
312 struct rsapubkey_if *pubkey;
313 struct transform_if **transforms;
316 struct hash_if *hash;
318 uint32_t index; /* Index of this site */
319 uint32_t local_capabilities;
320 int32_t setup_retries; /* How many times to send setup packets */
321 int32_t setup_retry_interval; /* Initial timeout for setup packets */
322 int32_t wait_timeout; /* How long to wait if setup unsuccessful */
323 int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
324 int32_t key_lifetime; /* How long a key lasts once set up */
325 int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
326 after this time, initiate a new
329 bool_t setup_priority; /* Do we have precedence if both sites emit
330 message 1 simultaneously? */
333 /* runtime information */
335 uint64_t now; /* Most recently seen time */
336 bool_t allow_send_prod;
338 int resolving_n_results_all;
339 int resolving_n_results_stored;
340 struct comm_addr resolving_results[MAX_PEER_ADDRS];
342 /* The currently established session */
343 struct data_key current;
344 struct data_key auxiliary_key;
345 bool_t auxiliary_is_new;
346 uint64_t renegotiate_key_time; /* When we can negotiate a new key */
347 uint64_t auxiliary_renegotiate_key_time;
348 transport_peers peers; /* Current address(es) of peer for data traffic */
350 /* The current key setup protocol exchange. We can only be
351 involved in one of these at a time. There's a potential for
352 denial of service here (the attacker keeps sending a setup
353 packet; we keep trying to continue the exchange, and have to
354 timeout before we can listen for another setup packet); perhaps
355 we should keep a list of 'bad' sources for setup packets. */
356 uint32_t remote_capabilities;
357 uint16_t remote_adv_mtu;
358 struct transform_if *chosen_transform;
359 uint32_t setup_session_id;
360 transport_peers setup_peers;
361 uint8_t localN[NONCELEN]; /* Nonces for key exchange */
362 uint8_t remoteN[NONCELEN];
363 struct buffer_if buffer; /* Current outgoing key exchange packet */
364 struct buffer_if scratch;
365 int32_t retries; /* Number of retries remaining */
366 uint64_t timeout; /* Timeout for current state */
368 uint8_t *sharedsecret;
369 uint32_t sharedsecretlen, sharedsecretallocd;
370 struct transform_inst_if *new_transform; /* For key setup/verify */
373 static uint32_t event_log_priority(struct site *st, uint32_t event)
375 if (!(event&st->log_events))
378 case LOG_UNEXPECTED: return M_INFO;
379 case LOG_SETUP_INIT: return M_INFO;
380 case LOG_SETUP_TIMEOUT: return M_NOTICE;
381 case LOG_ACTIVATE_KEY: return M_INFO;
382 case LOG_TIMEOUT_KEY: return M_INFO;
383 case LOG_SEC: return M_SECURITY;
384 case LOG_STATE: return M_DEBUG;
385 case LOG_DROP: return M_DEBUG;
386 case LOG_DUMP: return M_DEBUG;
387 case LOG_ERROR: return M_ERR;
388 case LOG_PEER_ADDRS: return M_DEBUG;
389 default: return M_ERR;
393 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
395 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
399 class=event_log_priority(st, event);
401 slilog_part(st->log,class,"%s: ",st->tunname);
402 vslilog_part(st->log,class,msg,ap);
403 slilog_part(st->log,class,"\n");
407 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
409 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
413 vslog(st,event,msg,ap);
417 static void logtimeout(struct site *st, const char *fmt, ...)
419 static void logtimeout(struct site *st, const char *fmt, ...)
421 uint32_t class=event_log_priority(st,LOG_SETUP_TIMEOUT);
428 slilog_part(st->log,class,"%s: ",st->tunname);
429 vslilog_part(st->log,class,fmt,ap);
433 for (i=0, delim=" (tried ";
434 i<st->setup_peers.npeers;
436 transport_peer *peer=&st->setup_peers.peers[i];
437 const char *s=comm_addr_to_string(&peer->addr);
438 slilog_part(st->log,class,"%s%s",delim,s);
441 slilog_part(st->log,class,")\n");
445 static void set_link_quality(struct site *st);
446 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
447 static void delete_one_key(struct site *st, struct data_key *key,
448 const char *reason /* may be 0 meaning don't log*/,
449 const char *which /* ignored if !reasonn */,
450 uint32_t loglevel /* ignored if !reasonn */);
451 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
452 const struct comm_addr *prod_hint);
453 static void enter_state_run(struct site *st);
454 static bool_t enter_state_resolve(struct site *st);
455 static void decrement_resolving_count(struct site *st, int by);
456 static bool_t enter_new_state(struct site *st,uint32_t next);
457 static void enter_state_wait(struct site *st);
458 static void activate_new_key(struct site *st);
460 static bool_t is_transform_valid(struct transform_inst_if *transform)
462 return transform && transform->valid(transform->st);
465 static bool_t current_valid(struct site *st)
467 return is_transform_valid(st->current.transform);
470 #define DEFINE_CALL_TRANSFORM(fwdrev) \
471 static int call_transform_##fwdrev(struct site *st, \
472 struct transform_inst_if *transform, \
473 struct buffer_if *buf, \
474 const char **errmsg) \
476 if (!is_transform_valid(transform)) { \
477 *errmsg="transform not set up"; \
480 return transform->fwdrev(transform->st,buf,errmsg); \
483 DEFINE_CALL_TRANSFORM(forwards)
484 DEFINE_CALL_TRANSFORM(reverse)
486 static void dispose_transform(struct transform_inst_if **transform_var)
488 struct transform_inst_if *transform=*transform_var;
490 transform->delkey(transform->st);
491 transform->destroy(transform->st);
496 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
497 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
498 #define CHECK_TYPE(b,t) do { uint32_t type; \
499 CHECK_AVAIL((b),4); \
500 type=buf_unprepend_uint32((b)); \
501 if (type!=(t)) return False; } while(0)
503 static _Bool type_is_msg34(uint32_t type)
506 type == LABEL_MSG3 ||
507 type == LABEL_MSG3BIS ||
514 struct buffer_if extrainfo;
521 struct parsedname remote;
522 struct parsedname local;
523 uint32_t remote_capabilities;
525 int capab_transformnum;
535 static void set_new_transform(struct site *st, char *pk)
537 /* Make room for the shared key */
538 st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
539 assert(st->sharedsecretlen);
540 if (st->sharedsecretlen > st->sharedsecretallocd) {
541 st->sharedsecretallocd=st->sharedsecretlen;
542 st->sharedsecret=safe_realloc_ary(st->sharedsecret,1,
543 st->sharedsecretallocd,
544 "site:sharedsecret");
547 /* Generate the shared key */
548 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,pk,
549 st->sharedsecret,st->sharedsecretlen);
551 /* Set up the transform */
552 struct transform_if *generator=st->chosen_transform;
553 struct transform_inst_if *generated=generator->create(generator->st);
554 generated->setkey(generated->st,st->sharedsecret,
555 st->sharedsecretlen,st->setup_priority);
556 dispose_transform(&st->new_transform);
557 st->new_transform=generated;
559 slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
560 " %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
561 st->chosen_transform->capab_transformnum,
562 st->local_capabilities, st->remote_capabilities);
566 int32_t lenpos, afternul;
568 static void append_string_xinfo_start(struct buffer_if *buf,
569 struct xinfoadd *xia,
571 /* Helps construct one of the names with additional info as found
572 * in MSG1..4. Call this function first, then append all the
573 * desired extra info (not including the nul byte) to the buffer,
574 * then call append_string_xinfo_done. */
576 xia->lenpos = buf->size;
577 buf_append_string(buf,str);
578 buf_append_uint8(buf,0);
579 xia->afternul = buf->size;
581 static void append_string_xinfo_done(struct buffer_if *buf,
582 struct xinfoadd *xia)
584 /* we just need to adjust the string length */
585 if (buf->size == xia->afternul) {
586 /* no extra info, strip the nul too */
587 buf_unappend_uint8(buf);
589 put_uint16(buf->start+xia->lenpos, buf->size-(xia->lenpos+2));
593 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
594 out using a transform of config data supplied by netlink */
595 static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what)
601 st->retries=st->setup_retries;
602 BUF_ALLOC(&st->buffer,what);
603 buffer_init(&st->buffer,0);
604 buf_append_uint32(&st->buffer,
605 (type==LABEL_MSG1?0:st->setup_session_id));
606 buf_append_uint32(&st->buffer,st->index);
607 buf_append_uint32(&st->buffer,type);
610 append_string_xinfo_start(&st->buffer,&xia,st->localname);
611 if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
612 buf_append_uint32(&st->buffer,st->local_capabilities);
614 if (type_is_msg34(type)) {
615 buf_append_uint16(&st->buffer,st->mtu_target);
617 append_string_xinfo_done(&st->buffer,&xia);
619 buf_append_string(&st->buffer,st->remotename);
620 BUF_ADD_OBJ(append,&st->buffer,st->localN);
621 if (type==LABEL_MSG1) return True;
622 BUF_ADD_OBJ(append,&st->buffer,st->remoteN);
623 if (type==LABEL_MSG2) return True;
625 if (hacky_par_mid_failnow()) return False;
627 if (type==LABEL_MSG3BIS)
628 buf_append_uint8(&st->buffer,st->chosen_transform->capab_transformnum);
630 dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
631 buf_append_string(&st->buffer,dhpub);
633 hash=safe_malloc(st->hash->len, "generate_msg");
634 hst=st->hash->init();
635 st->hash->update(hst,st->buffer.start,st->buffer.size);
636 st->hash->final(hst,hash);
637 sig=st->privkey->sign(st->privkey->st,hash,st->hash->len);
638 buf_append_string(&st->buffer,sig);
644 static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
647 nm->len=buf_unprepend_uint16(msg);
648 CHECK_AVAIL(msg,nm->len);
649 nm->name=buf_unprepend(msg,nm->len);
650 uint8_t *nul=memchr(nm->name,0,nm->len);
652 buffer_readonly_view(&nm->extrainfo,0,0);
654 buffer_readonly_view(&nm->extrainfo, nul+1, msg->start-(nul+1));
655 nm->len=nul-nm->name;
660 static bool_t unpick_msg(struct site *st, uint32_t type,
661 struct buffer_if *msg, struct msg *m)
663 m->capab_transformnum=-1;
664 m->hashstart=msg->start;
666 m->dest=buf_unprepend_uint32(msg);
668 m->source=buf_unprepend_uint32(msg);
669 CHECK_TYPE(msg,type);
670 if (!unpick_name(msg,&m->remote)) return False;
671 m->remote_capabilities=0;
673 if (m->remote.extrainfo.size) {
674 CHECK_AVAIL(&m->remote.extrainfo,4);
675 m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
677 if (type_is_msg34(type) && m->remote.extrainfo.size) {
678 CHECK_AVAIL(&m->remote.extrainfo,2);
679 m->remote_mtu=buf_unprepend_uint16(&m->remote.extrainfo);
681 if (!unpick_name(msg,&m->local)) return False;
682 if (type==LABEL_PROD) {
686 CHECK_AVAIL(msg,NONCELEN);
687 m->nR=buf_unprepend(msg,NONCELEN);
688 if (type==LABEL_MSG1) {
692 CHECK_AVAIL(msg,NONCELEN);
693 m->nL=buf_unprepend(msg,NONCELEN);
694 if (type==LABEL_MSG2) {
698 if (type==LABEL_MSG3BIS) {
700 m->capab_transformnum = buf_unprepend_uint8(msg);
702 m->capab_transformnum = CAPAB_TRANSFORMNUM_ANCIENT;
705 m->pklen=buf_unprepend_uint16(msg);
706 CHECK_AVAIL(msg,m->pklen);
707 m->pk=buf_unprepend(msg,m->pklen);
708 m->hashlen=msg->start-m->hashstart;
710 m->siglen=buf_unprepend_uint16(msg);
711 CHECK_AVAIL(msg,m->siglen);
712 m->sig=buf_unprepend(msg,m->siglen);
717 static bool_t name_matches(const struct parsedname *nm, const char *expected)
719 int expected_len=strlen(expected);
721 nm->len == expected_len &&
722 !memcmp(nm->name, expected, expected_len);
725 static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
728 if (type==LABEL_MSG1) return True;
730 /* Check that the site names and our nonce have been sent
731 back correctly, and then store our peer's nonce. */
732 if (!name_matches(&m->remote,st->remotename)) {
733 *error="wrong remote site name";
736 if (!name_matches(&m->local,st->localname)) {
737 *error="wrong local site name";
740 if (memcmp(m->nL,st->localN,NONCELEN)!=0) {
741 *error="wrong locally-generated nonce";
744 if (type==LABEL_MSG2) return True;
745 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
746 *error="wrong remotely-generated nonce";
749 /* MSG3 has complicated rules about capabilities, which are
750 * handled in process_msg3. */
751 if (type==LABEL_MSG3 || type==LABEL_MSG3BIS) return True;
752 if (m->remote_capabilities!=st->remote_capabilities) {
753 *error="remote capabilities changed";
756 if (type==LABEL_MSG4) return True;
757 *error="unknown message type";
761 static bool_t generate_msg1(struct site *st)
763 st->random->generate(st->random->st,NONCELEN,st->localN);
764 return generate_msg(st,LABEL_MSG1,"site:MSG1");
767 static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
768 const struct comm_addr *src, struct msg *m)
770 /* We've already determined we're in an appropriate state to
771 process an incoming MSG1, and that the MSG1 has correct values
774 st->setup_session_id=m->source;
775 st->remote_capabilities=m->remote_capabilities;
776 memcpy(st->remoteN,m->nR,NONCELEN);
780 static bool_t generate_msg2(struct site *st)
782 st->random->generate(st->random->st,NONCELEN,st->localN);
783 return generate_msg(st,LABEL_MSG2,"site:MSG2");
786 static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
787 const struct comm_addr *src)
792 if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False;
793 if (!check_msg(st,LABEL_MSG2,&m,&err)) {
794 slog(st,LOG_SEC,"msg2: %s",err);
797 st->setup_session_id=m.source;
798 st->remote_capabilities=m.remote_capabilities;
800 /* Select the transform to use */
802 uint32_t remote_transforms = st->remote_capabilities & CAPAB_TRANSFORM_MASK;
803 if (!remote_transforms)
804 /* old secnets only had this one transform */
805 remote_transforms = 1UL << CAPAB_TRANSFORMNUM_ANCIENT;
807 struct transform_if *ti;
809 for (i=0; i<st->ntransforms; i++) {
810 ti=st->transforms[i];
811 if ((1UL << ti->capab_transformnum) & remote_transforms)
812 goto transform_found;
814 slog(st,LOG_ERROR,"no transforms in common"
815 " (us %#"PRIx32"; them: %#"PRIx32")",
816 st->local_capabilities & CAPAB_TRANSFORM_MASK,
820 st->chosen_transform=ti;
822 memcpy(st->remoteN,m.nR,NONCELEN);
826 static bool_t generate_msg3(struct site *st)
828 /* Now we have our nonce and their nonce. Think of a secret key,
829 and create message number 3. */
830 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
831 return generate_msg(st,
832 (st->remote_capabilities & CAPAB_TRANSFORM_MASK
833 ? LABEL_MSG3BIS : LABEL_MSG3),
837 static bool_t process_msg3_msg4(struct site *st, struct msg *m)
842 /* Check signature and store g^x mod m */
843 hash=safe_malloc(st->hash->len, "process_msg3_msg4");
844 hst=st->hash->init();
845 st->hash->update(hst,m->hashstart,m->hashlen);
846 st->hash->final(hst,hash);
847 /* Terminate signature with a '0' - cheating, but should be ok */
849 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m->sig)) {
850 slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
856 st->remote_adv_mtu=m->remote_mtu;
861 static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
862 const struct comm_addr *src, uint32_t msgtype)
867 assert(msgtype==LABEL_MSG3 || msgtype==LABEL_MSG3BIS);
869 if (!unpick_msg(st,msgtype,msg3,&m)) return False;
870 if (!check_msg(st,msgtype,&m,&err)) {
871 slog(st,LOG_SEC,"msg3: %s",err);
874 uint32_t capab_adv_late = m.remote_capabilities
875 & ~st->remote_capabilities & CAPAB_EARLY;
876 if (capab_adv_late) {
877 slog(st,LOG_SEC,"msg3 impermissibly adds early capability flag(s)"
878 " %#"PRIx32" (was %#"PRIx32", now %#"PRIx32")",
879 capab_adv_late, st->remote_capabilities, m.remote_capabilities);
882 st->remote_capabilities|=m.remote_capabilities;
884 struct transform_if *ti;
886 for (i=0; i<st->ntransforms; i++) {
887 ti=st->transforms[i];
888 if (ti->capab_transformnum == m.capab_transformnum)
889 goto transform_found;
891 slog(st,LOG_SEC,"peer chose unknown-to-us transform %d!",
892 m.capab_transformnum);
895 st->chosen_transform=ti;
897 if (!process_msg3_msg4(st,&m))
900 /* Terminate their DH public key with a '0' */
902 /* Invent our DH secret key */
903 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
905 /* Generate the shared key and set up the transform */
906 set_new_transform(st,m.pk);
911 static bool_t generate_msg4(struct site *st)
913 /* We have both nonces, their public key and our private key. Generate
914 our public key, sign it and send it to them. */
915 return generate_msg(st,LABEL_MSG4,"site:MSG4");
918 static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
919 const struct comm_addr *src)
924 if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
925 if (!check_msg(st,LABEL_MSG4,&m,&err)) {
926 slog(st,LOG_SEC,"msg4: %s",err);
930 if (!process_msg3_msg4(st,&m))
933 /* Terminate their DH public key with a '0' */
936 /* Generate the shared key and set up the transform */
937 set_new_transform(st,m.pk);
948 static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0,
952 m->dest=buf_unprepend_uint32(msg0);
954 m->source=buf_unprepend_uint32(msg0);
956 m->type=buf_unprepend_uint32(msg0);
958 /* Leaves transformed part of buffer untouched */
961 static bool_t generate_msg5(struct site *st)
963 cstring_t transform_err;
965 BUF_ALLOC(&st->buffer,"site:MSG5");
966 /* We are going to add four words to the message */
967 buffer_init(&st->buffer,calculate_max_start_pad());
968 /* Give the netlink code an opportunity to put its own stuff in the
969 message (configuration information, etc.) */
970 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
971 if (call_transform_forwards(st,st->new_transform,
972 &st->buffer,&transform_err))
974 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
975 buf_prepend_uint32(&st->buffer,st->index);
976 buf_prepend_uint32(&st->buffer,st->setup_session_id);
978 st->retries=st->setup_retries;
982 static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
983 const struct comm_addr *src,
984 struct transform_inst_if *transform)
987 cstring_t transform_err;
989 if (!unpick_msg0(st,msg5,&m)) return False;
991 if (call_transform_reverse(st,transform,msg5,&transform_err)) {
992 /* There's a problem */
993 slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
996 /* Buffer should now contain untransformed PING packet data */
998 if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) {
999 slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
1002 /* Older versions of secnet used to write some config data here
1003 * which we ignore. So we don't CHECK_EMPTY */
1007 static void create_msg6(struct site *st, struct transform_inst_if *transform,
1008 uint32_t session_id)
1010 cstring_t transform_err;
1012 BUF_ALLOC(&st->buffer,"site:MSG6");
1013 /* We are going to add four words to the message */
1014 buffer_init(&st->buffer,calculate_max_start_pad());
1015 /* Give the netlink code an opportunity to put its own stuff in the
1016 message (configuration information, etc.) */
1017 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1018 int problem = call_transform_forwards(st,transform,
1019 &st->buffer,&transform_err);
1021 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1022 buf_prepend_uint32(&st->buffer,st->index);
1023 buf_prepend_uint32(&st->buffer,session_id);
1026 static bool_t generate_msg6(struct site *st)
1028 if (!is_transform_valid(st->new_transform))
1030 create_msg6(st,st->new_transform,st->setup_session_id);
1031 st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
1035 static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
1036 const struct comm_addr *src)
1039 cstring_t transform_err;
1041 if (!unpick_msg0(st,msg6,&m)) return False;
1043 if (call_transform_reverse(st,st->new_transform,msg6,&transform_err)) {
1044 /* There's a problem */
1045 slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
1048 /* Buffer should now contain untransformed PING packet data */
1049 CHECK_AVAIL(msg6,4);
1050 if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) {
1051 slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
1054 /* Older versions of secnet used to write some config data here
1055 * which we ignore. So we don't CHECK_EMPTY */
1059 static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
1060 const struct comm_addr *src)
1062 cstring_t transform_err, auxkey_err, newkey_err="n/a";
1066 if (!unpick_msg0(st,msg0,&m)) return False;
1068 /* Keep a copy so we can try decrypting it with multiple keys */
1069 buffer_copy(&st->scratch, msg0);
1071 problem = call_transform_reverse(st,st->current.transform,
1072 msg0,&transform_err);
1074 if (!st->auxiliary_is_new)
1075 delete_one_key(st,&st->auxiliary_key,
1076 "peer has used new key","auxiliary key",LOG_SEC);
1082 buffer_copy(msg0, &st->scratch);
1083 problem = call_transform_reverse(st,st->auxiliary_key.transform,
1086 slog(st,LOG_DROP,"processing packet which uses auxiliary key");
1087 if (st->auxiliary_is_new) {
1088 /* We previously timed out in state SENTMSG5 but it turns
1089 * out that our peer did in fact get our MSG5 and is
1090 * using the new key. So we should switch to it too. */
1091 /* This is a bit like activate_new_key. */
1094 st->current=st->auxiliary_key;
1095 st->auxiliary_key=t;
1097 delete_one_key(st,&st->auxiliary_key,"peer has used new key",
1098 "previous key",LOG_SEC);
1099 st->auxiliary_is_new=0;
1100 st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
1107 if (st->state==SITE_SENTMSG5) {
1108 buffer_copy(msg0, &st->scratch);
1109 problem = call_transform_reverse(st,st->new_transform,
1112 /* It looks like we didn't get the peer's MSG6 */
1113 /* This is like a cut-down enter_new_state(SITE_RUN) */
1114 slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
1115 BUF_FREE(&st->buffer);
1117 activate_new_key(st);
1118 return True; /* do process the data in this packet */
1124 slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
1125 transform_err,auxkey_err,newkey_err);
1126 initiate_key_setup(st,"incoming message would not decrypt",0);
1127 send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
1131 slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
1135 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
1136 const struct comm_addr *src)
1140 if (!decrypt_msg0(st,msg0,src))
1143 CHECK_AVAIL(msg0,4);
1144 type=buf_unprepend_uint32(msg0);
1147 /* We must forget about the current session. */
1148 delete_keys(st,"request from peer",LOG_SEC);
1151 /* Deliver to netlink layer */
1152 st->netlink->deliver(st->netlink->st,msg0);
1153 transport_data_msgok(st,src);
1154 /* See whether we should start negotiating a new key */
1155 if (st->now > st->renegotiate_key_time)
1156 initiate_key_setup(st,"incoming packet in renegotiation window",0);
1159 slog(st,LOG_SEC,"incoming encrypted message of type %08x "
1166 static void dump_packet(struct site *st, struct buffer_if *buf,
1167 const struct comm_addr *addr, bool_t incoming,
1170 uint32_t dest=get_uint32(buf->start);
1171 uint32_t source=get_uint32(buf->start+4);
1172 uint32_t msgtype=get_uint32(buf->start+8);
1174 if (st->log_events & LOG_DUMP)
1175 slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x: %s%s",
1176 st->tunname,incoming?"incoming":"outgoing",
1177 dest,source,msgtype,comm_addr_to_string(addr),
1181 static uint32_t site_status(void *st)
1186 static bool_t send_msg(struct site *st)
1188 if (st->retries>0) {
1189 transport_xmit(st, &st->setup_peers, &st->buffer, True);
1190 st->timeout=st->now+st->setup_retry_interval;
1193 } else if (st->state==SITE_SENTMSG5) {
1194 logtimeout(st,"timed out sending MSG5, stashing new key");
1195 /* We stash the key we have produced, in case it turns out that
1196 * our peer did see our MSG5 after all and starts using it. */
1197 /* This is a bit like some of activate_new_key */
1198 struct transform_inst_if *t;
1199 t=st->auxiliary_key.transform;
1200 st->auxiliary_key.transform=st->new_transform;
1201 st->new_transform=t;
1202 dispose_transform(&st->new_transform);
1204 st->auxiliary_is_new=1;
1205 st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
1206 st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
1207 st->auxiliary_key.remote_session_id=st->setup_session_id;
1209 enter_state_wait(st);
1212 logtimeout(st,"timed out sending key setup packet "
1213 "(in state %s)",state_name(st->state));
1214 enter_state_wait(st);
1219 static void site_resolve_callback(void *sst, const struct comm_addr *addrs,
1220 int stored_naddrs, int all_naddrs,
1221 const char *address, const char *failwhy)
1223 struct site *st=sst;
1225 if (!stored_naddrs) {
1226 slog(st,LOG_ERROR,"resolution of %s failed: %s",address,failwhy);
1228 slog(st,LOG_PEER_ADDRS,"resolution of %s completed, %d addrs, eg: %s",
1229 address, all_naddrs, comm_addr_to_string(&addrs[0]));;
1231 int space=st->transport_peers_max-st->resolving_n_results_stored;
1232 int n_tocopy=MIN(stored_naddrs,space);
1233 COPY_ARRAY(st->resolving_results + st->resolving_n_results_stored,
1236 st->resolving_n_results_stored += n_tocopy;
1237 st->resolving_n_results_all += all_naddrs;
1240 decrement_resolving_count(st,1);
1243 static void decrement_resolving_count(struct site *st, int by)
1245 assert(st->resolving_count>0);
1246 st->resolving_count-=by;
1248 if (st->resolving_count)
1251 /* OK, we are done with them all. Handle combined results. */
1253 const struct comm_addr *addrs=st->resolving_results;
1254 int naddrs=st->resolving_n_results_stored;
1255 assert(naddrs<=st->transport_peers_max);
1258 if (naddrs != st->resolving_n_results_all) {
1259 slog(st,LOG_SETUP_INIT,"resolution of supplied addresses/names"
1260 " yielded too many results (%d > %d), some ignored",
1261 st->resolving_n_results_all, naddrs);
1263 slog(st,LOG_STATE,"resolution completed, %d addrs, eg: %s",
1264 naddrs, iaddr_to_string(&addrs[0].ia));;
1267 switch (st->state) {
1269 if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) {
1270 enter_new_state(st,SITE_SENTMSG1);
1272 /* Can't figure out who to try to to talk to */
1273 slog(st,LOG_SETUP_INIT,
1274 "key exchange failed: cannot find peer address");
1275 enter_state_run(st);
1278 case SITE_SENTMSG1: case SITE_SENTMSG2:
1279 case SITE_SENTMSG3: case SITE_SENTMSG4:
1282 /* We start using the address immediately for data too.
1283 * It's best to store it in st->peers now because we might
1284 * go via SENTMSG5, WAIT, and a MSG0, straight into using
1285 * the new key (without updating the data peer addrs). */
1286 transport_resolve_complete(st,addrs,naddrs);
1287 } else if (st->local_mobile) {
1288 /* We can't let this rest because we may have a peer
1289 * address which will break in the future. */
1290 slog(st,LOG_SETUP_INIT,"resolution failed: "
1291 "abandoning key exchange");
1292 enter_state_wait(st);
1294 slog(st,LOG_SETUP_INIT,"resolution failed: "
1295 " continuing to use source address of peer's packets"
1296 " for key exchange and ultimately data");
1301 slog(st,LOG_SETUP_INIT,"resolution completed tardily,"
1302 " updating peer address(es)");
1303 transport_resolve_complete_tardy(st,addrs,naddrs);
1304 } else if (st->local_mobile) {
1305 /* Not very good. We should queue (another) renegotiation
1306 * so that we can update the peer address. */
1307 st->key_renegotiate_time=st->now+st->wait_timeout;
1309 slog(st,LOG_SETUP_INIT,"resolution failed: "
1310 " continuing to use source address of peer's packets");
1320 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
1321 const struct comm_addr *prod_hint)
1323 /* Reentrancy hazard: can call enter_new_state/enter_state_* */
1324 if (st->state!=SITE_RUN) return False;
1325 slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
1326 if (st->addresses) {
1327 slog(st,LOG_SETUP_INIT,"resolving peer address(es)");
1328 return enter_state_resolve(st);
1329 } else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) {
1330 return enter_new_state(st,SITE_SENTMSG1);
1332 slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
1336 static void activate_new_key(struct site *st)
1338 struct transform_inst_if *t;
1340 /* We have three transform instances, which we swap between old,
1342 t=st->auxiliary_key.transform;
1343 st->auxiliary_key.transform=st->current.transform;
1344 st->current.transform=st->new_transform;
1345 st->new_transform=t;
1346 dispose_transform(&st->new_transform);
1349 st->auxiliary_is_new=0;
1350 st->auxiliary_key.key_timeout=st->current.key_timeout;
1351 st->current.key_timeout=st->now+st->key_lifetime;
1352 st->renegotiate_key_time=st->now+st->key_renegotiate_time;
1353 transport_peers_copy(st,&st->peers,&st->setup_peers);
1354 st->current.remote_session_id=st->setup_session_id;
1356 /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
1357 * But their mtu be unspecified, in which case we just use ours. */
1358 uint32_t intersite_mtu=
1359 MIN(st->mtu_target, st->remote_adv_mtu ?: ~(uint32_t)0);
1360 st->netlink->set_mtu(st->netlink->st,intersite_mtu);
1362 slog(st,LOG_ACTIVATE_KEY,"new key activated"
1363 " (mtu ours=%"PRId32" theirs=%"PRId32" intersite=%"PRId32")",
1364 st->mtu_target, st->remote_adv_mtu, intersite_mtu);
1365 enter_state_run(st);
1368 static void delete_one_key(struct site *st, struct data_key *key,
1369 cstring_t reason, cstring_t which, uint32_t loglevel)
1371 if (!is_transform_valid(key->transform)) return;
1372 if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
1373 dispose_transform(&key->transform);
1377 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
1379 if (current_valid(st)) {
1380 slog(st,loglevel,"session closed (%s)",reason);
1382 delete_one_key(st,&st->current,0,0,0);
1383 set_link_quality(st);
1385 delete_one_key(st,&st->auxiliary_key,0,0,0);
1388 static void state_assert(struct site *st, bool_t ok)
1390 if (!ok) fatal("site:state_assert");
1393 static void enter_state_stop(struct site *st)
1395 st->state=SITE_STOP;
1397 delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
1398 dispose_transform(&st->new_transform);
1401 static void set_link_quality(struct site *st)
1404 if (current_valid(st))
1405 quality=LINK_QUALITY_UP;
1406 else if (st->state==SITE_WAIT || st->state==SITE_STOP)
1407 quality=LINK_QUALITY_DOWN;
1408 else if (st->addresses)
1409 quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
1410 else if (transport_peers_valid(&st->peers))
1411 quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
1413 quality=LINK_QUALITY_DOWN;
1415 st->netlink->set_quality(st->netlink->st,quality);
1418 static void enter_state_run(struct site *st)
1420 slog(st,LOG_STATE,"entering state RUN");
1424 st->setup_session_id=0;
1425 transport_peers_clear(st,&st->setup_peers);
1426 FILLZERO(st->localN);
1427 FILLZERO(st->remoteN);
1428 dispose_transform(&st->new_transform);
1429 memset(st->dhsecret,0,st->dh->len);
1430 memset(st->sharedsecret,0,st->sharedsecretlen);
1431 set_link_quality(st);
1434 static bool_t ensure_resolving(struct site *st)
1436 /* Reentrancy hazard: may call site_resolve_callback and hence
1437 * enter_new_state, enter_state_* and generate_msg*. */
1438 if (st->resolving_count)
1441 assert(st->addresses);
1443 /* resolver->request might reentrantly call site_resolve_callback
1444 * which will decrement st->resolving, so we need to increment it
1445 * twice beforehand to prevent decrement from thinking we're
1446 * finished, and decrement it ourselves. Alternatively if
1447 * everything fails then there are no callbacks due and we simply
1448 * set it to 0 and return false.. */
1449 st->resolving_n_results_stored=0;
1450 st->resolving_n_results_all=0;
1451 st->resolving_count+=2;
1452 const char **addrp=st->addresses;
1453 const char *address;
1455 for (; (address=*addrp++); ) {
1456 bool_t ok = st->resolver->request(st->resolver->st,address,
1457 st->remoteport,st->comms[0],
1458 site_resolve_callback,st);
1460 st->resolving_count++;
1464 st->resolving_count=0;
1467 decrement_resolving_count(st,2);
1471 static bool_t enter_state_resolve(struct site *st)
1473 /* Reentrancy hazard! See ensure_resolving. */
1474 state_assert(st,st->state==SITE_RUN);
1475 slog(st,LOG_STATE,"entering state RESOLVE");
1476 st->state=SITE_RESOLVE;
1477 return ensure_resolving(st);
1480 static bool_t enter_new_state(struct site *st, uint32_t next)
1482 bool_t (*gen)(struct site *st);
1485 slog(st,LOG_STATE,"entering state %s",state_name(next));
1488 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
1492 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1493 st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
1497 state_assert(st,st->state==SITE_SENTMSG1);
1498 BUF_FREE(&st->buffer);
1502 state_assert(st,st->state==SITE_SENTMSG2);
1503 BUF_FREE(&st->buffer);
1507 state_assert(st,st->state==SITE_SENTMSG3);
1508 BUF_FREE(&st->buffer);
1512 state_assert(st,st->state==SITE_SENTMSG4);
1513 BUF_FREE(&st->buffer);
1518 fatal("enter_new_state(%s): invalid new state",state_name(next));
1522 if (hacky_par_start_failnow()) return False;
1524 r= gen(st) && send_msg(st);
1527 st->setup_retries, st->setup_retry_interval,
1532 if (next==SITE_RUN) {
1533 BUF_FREE(&st->buffer); /* Never reused */
1534 st->timeout=0; /* Never retransmit */
1535 activate_new_key(st);
1539 slog(st,LOG_ERROR,"error entering state %s",state_name(next));
1540 st->buffer.free=False; /* Unconditionally use the buffer; it may be
1541 in either state, and enter_state_wait() will
1543 enter_state_wait(st);
1547 /* msg7 tells our peer that we're about to forget our key */
1548 static bool_t send_msg7(struct site *st, cstring_t reason)
1550 cstring_t transform_err;
1552 if (current_valid(st) && st->buffer.free
1553 && transport_peers_valid(&st->peers)) {
1554 BUF_ALLOC(&st->buffer,"site:MSG7");
1555 buffer_init(&st->buffer,calculate_max_start_pad());
1556 buf_append_uint32(&st->buffer,LABEL_MSG7);
1557 buf_append_string(&st->buffer,reason);
1558 if (call_transform_forwards(st, st->current.transform,
1559 &st->buffer, &transform_err))
1561 buf_prepend_uint32(&st->buffer,LABEL_MSG0);
1562 buf_prepend_uint32(&st->buffer,st->index);
1563 buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
1564 transport_xmit(st,&st->peers,&st->buffer,True);
1565 BUF_FREE(&st->buffer);
1572 /* We go into this state if our peer becomes uncommunicative. Similar to
1573 the "stop" state, we forget all session keys for a while, before
1574 re-entering the "run" state. */
1575 static void enter_state_wait(struct site *st)
1577 slog(st,LOG_STATE,"entering state WAIT");
1578 st->timeout=st->now+st->wait_timeout;
1579 st->state=SITE_WAIT;
1580 set_link_quality(st);
1581 BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
1582 /* XXX Erase keys etc. */
1585 static void generate_prod(struct site *st, struct buffer_if *buf)
1588 buf_append_uint32(buf,0);
1589 buf_append_uint32(buf,0);
1590 buf_append_uint32(buf,LABEL_PROD);
1591 buf_append_string(buf,st->localname);
1592 buf_append_string(buf,st->remotename);
1595 static void generate_send_prod(struct site *st,
1596 const struct comm_addr *source)
1598 if (!st->allow_send_prod) return; /* too soon */
1599 if (!(st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1600 st->state==SITE_WAIT)) return; /* we'd ignore peer's MSG1 */
1602 slog(st,LOG_SETUP_INIT,"prodding peer for key exchange");
1603 st->allow_send_prod=0;
1604 generate_prod(st,&st->scratch);
1605 bool_t ok = source->comm->sendmsg(source->comm->st, &st->scratch, source);
1606 dump_packet(st,&st->scratch,source,False,ok);
1609 static inline void site_settimeout(uint64_t timeout, int *timeout_io)
1612 int64_t offset=timeout-*now;
1613 if (offset<0) offset=0;
1614 if (offset>INT_MAX) offset=INT_MAX;
1615 if (*timeout_io<0 || offset<*timeout_io)
1620 static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
1623 struct site *st=sst;
1625 BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
1628 /* Work out when our next timeout is. The earlier of 'timeout' or
1629 'current.key_timeout'. A stored value of '0' indicates no timeout
1631 site_settimeout(st->timeout, timeout_io);
1632 site_settimeout(st->current.key_timeout, timeout_io);
1633 site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
1635 return 0; /* success */
1638 static void check_expiry(struct site *st, struct data_key *key,
1641 if (key->key_timeout && *now>key->key_timeout) {
1642 delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
1646 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1647 static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
1649 struct site *st=sst;
1652 if (st->timeout && *now>st->timeout) {
1654 if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) {
1655 if (!hacky_par_start_failnow())
1657 } else if (st->state==SITE_WAIT) {
1658 enter_state_run(st);
1660 slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d",
1664 check_expiry(st,&st->current,"current key");
1665 check_expiry(st,&st->auxiliary_key,"auxiliary key");
1668 /* This function is called by the netlink device to deliver packets
1669 intended for the remote network. The packet is in "raw" wire
1670 format, but is guaranteed to be word-aligned. */
1671 static void site_outgoing(void *sst, struct buffer_if *buf)
1673 struct site *st=sst;
1674 cstring_t transform_err;
1676 if (st->state==SITE_STOP) {
1681 st->allow_send_prod=1;
1683 /* In all other states we consider delivering the packet if we have
1684 a valid key and a valid address to send it to. */
1685 if (current_valid(st) && transport_peers_valid(&st->peers)) {
1686 /* Transform it and send it */
1688 buf_prepend_uint32(buf,LABEL_MSG9);
1689 if (call_transform_forwards(st, st->current.transform,
1690 buf, &transform_err))
1692 buf_prepend_uint32(buf,LABEL_MSG0);
1693 buf_prepend_uint32(buf,st->index);
1694 buf_prepend_uint32(buf,st->current.remote_session_id);
1695 transport_xmit(st,&st->peers,buf,False);
1702 slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size);
1704 initiate_key_setup(st,"outgoing packet",0);
1707 static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
1708 uint32_t type, struct msg *m)
1709 /* For packets which are identified by the local and remote names.
1710 * If it has our name and our peer's name in it it's for us. */
1712 struct buffer_if buf[1];
1713 buffer_readonly_clone(buf,buf_in);
1714 return unpick_msg(st,type,buf,m)
1715 && name_matches(&m->remote,st->remotename)
1716 && name_matches(&m->local,st->localname);
1719 /* This function is called by the communication device to deliver
1720 packets from our peers.
1721 It should return True if the packet is recognised as being for
1722 this current site instance (and should therefore not be processed
1723 by other sites), even if the packet was otherwise ignored. */
1724 static bool_t site_incoming(void *sst, struct buffer_if *buf,
1725 const struct comm_addr *source)
1727 struct site *st=sst;
1729 if (buf->size < 12) return False;
1731 uint32_t dest=get_uint32(buf->start);
1732 uint32_t msgtype=get_uint32(buf->start+8);
1733 struct msg named_msg;
1735 if (msgtype==LABEL_MSG1) {
1736 if (!named_for_us(st,buf,msgtype,&named_msg))
1738 /* It's a MSG1 addressed to us. Decide what to do about it. */
1739 dump_packet(st,buf,source,True,True);
1740 if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1741 st->state==SITE_WAIT) {
1742 /* We should definitely process it */
1743 transport_compute_setupinit_peers(st,0,0,source);
1744 if (process_msg1(st,buf,source,&named_msg)) {
1745 slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
1746 bool_t entered=enter_new_state(st,SITE_SENTMSG2);
1747 if (entered && st->addresses && st->local_mobile)
1748 /* We must do this as the very last thing, because
1749 the resolver callback might reenter us. */
1750 ensure_resolving(st);
1752 slog(st,LOG_ERROR,"failed to process incoming msg1");
1756 } else if (st->state==SITE_SENTMSG1) {
1757 /* We've just sent a message 1! They may have crossed on
1758 the wire. If we have priority then we ignore the
1759 incoming one, otherwise we process it as usual. */
1760 if (st->setup_priority) {
1762 slog(st,LOG_DUMP,"crossed msg1s; we are higher "
1763 "priority => ignore incoming msg1");
1766 slog(st,LOG_DUMP,"crossed msg1s; we are lower "
1767 "priority => use incoming msg1");
1768 if (process_msg1(st,buf,source,&named_msg)) {
1769 BUF_FREE(&st->buffer); /* Free our old message 1 */
1770 transport_setup_msgok(st,source);
1771 enter_new_state(st,SITE_SENTMSG2);
1773 slog(st,LOG_ERROR,"failed to process an incoming "
1774 "crossed msg1 (we have low priority)");
1780 /* The message 1 was received at an unexpected stage of the
1781 key setup. XXX POLICY - what do we do? */
1782 slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
1786 if (msgtype==LABEL_PROD) {
1787 if (!named_for_us(st,buf,msgtype,&named_msg))
1789 dump_packet(st,buf,source,True,True);
1790 if (st->state!=SITE_RUN) {
1791 slog(st,LOG_DROP,"ignoring PROD when not in state RUN");
1792 } else if (current_valid(st)) {
1793 slog(st,LOG_DROP,"ignoring PROD when we think we have a key");
1795 initiate_key_setup(st,"peer sent PROD packet",source);
1800 if (dest==st->index) {
1801 /* Explicitly addressed to us */
1802 if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True,True);
1805 /* If the source is our current peer then initiate a key setup,
1806 because our peer's forgotten the key */
1807 if (get_uint32(buf->start+4)==st->current.remote_session_id) {
1809 initiated = initiate_key_setup(st,"received a NAK",source);
1810 if (!initiated) generate_send_prod(st,source);
1812 slog(st,LOG_SEC,"bad incoming NAK");
1816 process_msg0(st,buf,source);
1819 /* Setup packet: should not have been explicitly addressed
1821 slog(st,LOG_SEC,"incoming explicitly addressed msg1");
1824 /* Setup packet: expected only in state SENTMSG1 */
1825 if (st->state!=SITE_SENTMSG1) {
1826 slog(st,LOG_UNEXPECTED,"unexpected MSG2");
1827 } else if (process_msg2(st,buf,source)) {
1828 transport_setup_msgok(st,source);
1829 enter_new_state(st,SITE_SENTMSG3);
1831 slog(st,LOG_SEC,"invalid MSG2");
1836 /* Setup packet: expected only in state SENTMSG2 */
1837 if (st->state!=SITE_SENTMSG2) {
1838 slog(st,LOG_UNEXPECTED,"unexpected MSG3");
1839 } else if (process_msg3(st,buf,source,msgtype)) {
1840 transport_setup_msgok(st,source);
1841 enter_new_state(st,SITE_SENTMSG4);
1843 slog(st,LOG_SEC,"invalid MSG3");
1847 /* Setup packet: expected only in state SENTMSG3 */
1848 if (st->state!=SITE_SENTMSG3) {
1849 slog(st,LOG_UNEXPECTED,"unexpected MSG4");
1850 } else if (process_msg4(st,buf,source)) {
1851 transport_setup_msgok(st,source);
1852 enter_new_state(st,SITE_SENTMSG5);
1854 slog(st,LOG_SEC,"invalid MSG4");
1858 /* Setup packet: expected only in state SENTMSG4 */
1859 /* (may turn up in state RUN if our return MSG6 was lost
1860 and the new key has already been activated. In that
1861 case we discard it. The peer will realise that we
1862 are using the new key when they see our data packets.
1863 Until then the peer's data packets to us get discarded. */
1864 if (st->state==SITE_SENTMSG4) {
1865 if (process_msg5(st,buf,source,st->new_transform)) {
1866 transport_setup_msgok(st,source);
1867 enter_new_state(st,SITE_RUN);
1869 slog(st,LOG_SEC,"invalid MSG5");
1871 } else if (st->state==SITE_RUN) {
1872 if (process_msg5(st,buf,source,st->current.transform)) {
1873 slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
1874 transport_setup_msgok(st,source);
1875 create_msg6(st,st->current.transform,
1876 st->current.remote_session_id);
1877 transport_xmit(st,&st->peers,&st->buffer,True);
1878 BUF_FREE(&st->buffer);
1880 slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
1883 slog(st,LOG_UNEXPECTED,"unexpected MSG5");
1887 /* Setup packet: expected only in state SENTMSG5 */
1888 if (st->state!=SITE_SENTMSG5) {
1889 slog(st,LOG_UNEXPECTED,"unexpected MSG6");
1890 } else if (process_msg6(st,buf,source)) {
1891 BUF_FREE(&st->buffer); /* Free message 5 */
1892 transport_setup_msgok(st,source);
1893 activate_new_key(st);
1895 slog(st,LOG_SEC,"invalid MSG6");
1899 slog(st,LOG_SEC,"received message of unknown type 0x%08x",
1910 static void site_control(void *vst, bool_t run)
1912 struct site *st=vst;
1913 if (run) enter_state_run(st);
1914 else enter_state_stop(st);
1917 static void site_phase_hook(void *sst, uint32_t newphase)
1919 struct site *st=sst;
1921 /* The program is shutting down; tell our peer */
1922 send_msg7(st,"shutting down");
1925 static void site_childpersist_clearkeys(void *sst, uint32_t newphase)
1927 struct site *st=sst;
1928 dispose_transform(&st->current.transform);
1929 dispose_transform(&st->auxiliary_key.transform);
1930 dispose_transform(&st->new_transform);
1931 /* Not much point overwiting the signing key, since we loaded it
1932 from disk, and it is only valid prospectively if at all,
1934 /* XXX it would be best to overwrite the DH state, because that
1935 _is_ relevant to forward secrecy. However we have no
1936 convenient interface for doing that and in practice gmp has
1937 probably dribbled droppings all over the malloc arena. A good
1938 way to fix this would be to have a privsep child for asymmetric
1939 crypto operations, but that's a task for another day. */
1942 static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
1945 static uint32_t index_sequence;
1953 st->cl.description="site";
1954 st->cl.type=CL_SITE;
1956 st->cl.interface=&st->ops;
1958 st->ops.control=site_control;
1959 st->ops.status=site_status;
1961 /* First parameter must be a dict */
1962 item=list_elem(args,0);
1963 if (!item || item->type!=t_dict)
1964 cfgfatal(loc,"site","parameter must be a dictionary\n");
1966 dict=item->data.dict;
1967 st->localname=dict_read_string(dict, "local-name", True, "site", loc);
1968 st->remotename=dict_read_string(dict, "name", True, "site", loc);
1970 st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
1972 dict_read_bool(dict,"local-mobile",False,"site",loc,False);
1974 /* Sanity check (which also allows the 'sites' file to include
1975 site() closures for all sites including our own): refuse to
1976 talk to ourselves */
1977 if (strcmp(st->localname,st->remotename)==0) {
1978 Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
1980 if (st->peer_mobile != st->local_mobile)
1981 cfgfatal(loc,"site","site %s's peer-mobile=%d"
1982 " but our local-mobile=%d\n",
1983 st->localname, st->peer_mobile, st->local_mobile);
1987 if (st->peer_mobile && st->local_mobile) {
1988 Message(M_WARNING,"site %s: site is mobile but so are we"
1989 " -> ignoring this site\n", st->remotename);
1994 assert(index_sequence < 0xffffffffUL);
1995 st->index = ++index_sequence;
1996 st->local_capabilities = 0;
1997 st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
1999 #define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
2000 list_t *things##_cfg=dict_lookup(dict,dictkey); \
2001 if (!things##_cfg) \
2002 cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
2003 st->nthings=list_length(things##_cfg); \
2004 NEW_ARY(st->things,st->nthings); \
2005 assert(st->nthings); \
2006 for (i=0; i<st->nthings; i++) { \
2007 item_t *item=list_elem(things##_cfg,i); \
2008 if (item->type!=t_closure) \
2009 cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
2010 closure_t *cl=item->data.closure; \
2011 if (cl->type!=CL_TYPE) \
2012 cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
2013 st->things[i]=cl->interface; \
2017 GET_CLOSURE_LIST("comm",comms,ncomms,CL_COMM);
2019 st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
2020 st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
2021 st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
2023 st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
2024 st->addresses=dict_read_string_array(dict,"address",False,"site",loc,0);
2026 st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
2027 else st->remoteport=0;
2028 st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc);
2030 GET_CLOSURE_LIST("transform",transforms,ntransforms,CL_TRANSFORM);
2032 st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
2033 st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
2035 #define DEFAULT(D) (st->peer_mobile || st->local_mobile \
2036 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
2037 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
2039 st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
2040 st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
2041 st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
2042 st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME);
2043 st->mtu_target= dict_read_number(dict,"mtu-target",False,"site",loc,0);
2045 st->mobile_peer_expiry= dict_read_number(
2046 dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
2048 const char *peerskey= st->peer_mobile
2049 ? "mobile-peers-max" : "static-peers-max";
2050 st->transport_peers_max= dict_read_number(
2051 dict,peerskey,False,"site",loc, st->addresses ? 4 : 3);
2052 if (st->transport_peers_max<1 ||
2053 st->transport_peers_max>MAX_PEER_ADDRS) {
2054 cfgfatal(loc,"site", "%s must be in range 1.."
2055 STRING(MAX_PEER_ADDRS) "\n", peerskey);
2058 if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
2059 st->key_renegotiate_time=st->key_lifetime/2;
2061 st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
2062 st->key_renegotiate_time=dict_read_number(
2063 dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
2064 if (st->key_renegotiate_time > st->key_lifetime) {
2065 cfgfatal(loc,"site",
2066 "renegotiate-time must be less than key-lifetime\n");
2069 st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
2070 log_event_table,"site");
2072 st->resolving_count=0;
2073 st->allow_send_prod=0;
2075 st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
2077 sprintf(st->tunname,"%s<->%s",st->localname,st->remotename);
2079 /* The information we expect to see in incoming messages of type 1 */
2080 /* fixme: lots of unchecked overflows here, but the results are only
2081 corrupted packets rather than undefined behaviour */
2082 st->setup_priority=(strcmp(st->localname,st->remotename)>0);
2084 buffer_new(&st->buffer,SETUP_BUFFER_LEN);
2086 buffer_new(&st->scratch,SETUP_BUFFER_LEN);
2087 BUF_ALLOC(&st->scratch,"site:scratch");
2089 /* We are interested in poll(), but only for timeouts. We don't have
2090 any fds of our own. */
2091 register_for_poll(st, site_beforepoll, site_afterpoll, "site");
2094 st->remote_capabilities=0;
2095 st->chosen_transform=0;
2096 st->current.key_timeout=0;
2097 st->auxiliary_key.key_timeout=0;
2098 transport_peers_clear(st,&st->peers);
2099 transport_peers_clear(st,&st->setup_peers);
2100 /* XXX mlock these */
2101 st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
2102 st->sharedsecretlen=st->sharedsecretallocd=0;
2105 for (i=0; i<st->ntransforms; i++) {
2106 struct transform_if *ti=st->transforms[i];
2107 uint32_t capbit = 1UL << ti->capab_transformnum;
2108 if (st->local_capabilities & capbit)
2109 slog(st,LOG_ERROR,"transformnum capability bit"
2110 " %d (%#"PRIx32") reused", ti->capab_transformnum, capbit);
2111 st->local_capabilities |= capbit;
2114 /* We need to register the remote networks with the netlink device */
2115 uint32_t netlink_mtu; /* local virtual interface mtu */
2116 st->netlink->reg(st->netlink->st, site_outgoing, st, &netlink_mtu);
2117 if (!st->mtu_target)
2118 st->mtu_target=netlink_mtu;
2120 for (i=0; i<st->ncomms; i++)
2121 st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
2123 st->current.transform=0;
2124 st->auxiliary_key.transform=0;
2125 st->new_transform=0;
2126 st->auxiliary_is_new=0;
2128 enter_state_stop(st);
2130 add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
2131 add_hook(PHASE_CHILDPERSIST,site_childpersist_clearkeys,st);
2133 return new_closure(&st->cl);
2136 void site_module(dict_t *dict)
2138 add_closure(dict,"site",site_apply);
2142 /***** TRANSPORT PEERS definitions *****/
2144 static void transport_peers_debug(struct site *st, transport_peers *dst,
2145 const char *didwhat,
2146 int nargs, const struct comm_addr *args,
2151 if (!(st->log_events & LOG_PEER_ADDRS))
2152 return; /* an optimisation */
2154 slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
2155 (dst==&st->peers ? "data" :
2156 dst==&st->setup_peers ? "setup" : "UNKNOWN"),
2157 didwhat, nargs, dst->npeers);
2159 for (i=0, argp=(void*)args;
2161 i++, (argp+=stride?stride:sizeof(*args))) {
2162 const struct comm_addr *ca=(void*)argp;
2163 slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
2164 i, comm_addr_to_string(ca));
2166 for (i=0; i<dst->npeers; i++) {
2167 struct timeval diff;
2168 timersub(tv_now,&dst->peers[i].last,&diff);
2169 const struct comm_addr *ca=&dst->peers[i].addr;
2170 slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
2171 i, comm_addr_to_string(ca),
2172 (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
2176 static void transport_peers_expire(struct site *st, transport_peers *peers) {
2177 /* peers must be sorted first */
2178 int previous_peers=peers->npeers;
2179 struct timeval oldest;
2180 oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
2181 oldest.tv_usec = tv_now->tv_usec;
2182 while (peers->npeers>1 &&
2183 timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
2185 if (peers->npeers != previous_peers)
2186 transport_peers_debug(st,peers,"expire", 0,0,0);
2189 static bool_t transport_peer_record_one(struct site *st, transport_peers *peers,
2190 const struct comm_addr *ca,
2191 const struct timeval *tv) {
2192 /* returns false if output is full */
2195 if (peers->npeers >= st->transport_peers_max)
2198 for (search=0; search<peers->npeers; search++)
2199 if (comm_addr_equal(&peers->peers[search].addr, ca))
2202 peers->peers[peers->npeers].addr = *ca;
2203 peers->peers[peers->npeers].last = *tv;
2208 static void transport_record_peers(struct site *st, transport_peers *peers,
2209 const struct comm_addr *addrs, int naddrs,
2211 /* We add addrs into peers. The new entries end up at the front
2212 * and displace entries towards the end (perhaps even off the
2213 * end). Any existing matching entries are moved up to the front.
2215 * Caller must first call transport_peers_expire. */
2217 if (naddrs==1 && peers->npeers>=1 &&
2218 comm_addr_equal(&addrs[0], &peers->peers[0].addr)) {
2219 /* optimisation, also avoids debug for trivial updates */
2220 peers->peers[0].last = *tv_now;
2224 int old_npeers=peers->npeers;
2225 transport_peer old_peers[old_npeers];
2226 COPY_ARRAY(old_peers,peers->peers,old_npeers);
2230 for (i=0; i<naddrs; i++) {
2231 if (!transport_peer_record_one(st,peers, &addrs[i], tv_now))
2234 for (i=0; i<old_npeers; i++) {
2235 const transport_peer *old=&old_peers[i];
2236 if (!transport_peer_record_one(st,peers, &old->addr, &old->last))
2240 transport_peers_debug(st,peers,m, naddrs,addrs,0);
2243 static void transport_expire_record_peers(struct site *st,
2244 transport_peers *peers,
2245 const struct comm_addr *addrs,
2246 int naddrs, const char *m) {
2247 /* Convenience function */
2248 transport_peers_expire(st,peers);
2249 transport_record_peers(st,peers,addrs,naddrs,m);
2252 static bool_t transport_compute_setupinit_peers(struct site *st,
2253 const struct comm_addr *configured_addrs /* 0 if none or not found */,
2254 int n_configured_addrs /* 0 if none or not found */,
2255 const struct comm_addr *incoming_packet_addr /* 0 if none */) {
2256 if (!n_configured_addrs && !incoming_packet_addr &&
2257 !transport_peers_valid(&st->peers))
2260 slog(st,LOG_SETUP_INIT,
2261 "using: %d configured addr(s);%s %d old peer addrs(es)",
2263 incoming_packet_addr ? " incoming packet address;" : "",
2266 /* Non-mobile peers try addresses until one is plausible. The
2267 * effect is that this code always tries first the configured
2268 * address if supplied, or otherwise the address of the incoming
2269 * PROD, or finally the existing data peer if one exists; this is
2272 transport_peers_copy(st,&st->setup_peers,&st->peers);
2273 transport_peers_expire(st,&st->setup_peers);
2275 if (incoming_packet_addr)
2276 transport_record_peers(st,&st->setup_peers,
2277 incoming_packet_addr,1, "incoming");
2279 if (n_configured_addrs)
2280 transport_record_peers(st,&st->setup_peers,
2281 configured_addrs,n_configured_addrs, "setupinit");
2283 assert(transport_peers_valid(&st->setup_peers));
2287 static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
2288 if (st->peer_mobile)
2289 transport_expire_record_peers(st,&st->setup_peers,a,1,"setupmsg");
2291 static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
2292 if (st->peer_mobile)
2293 transport_expire_record_peers(st,&st->peers,a,1,"datamsg");
2296 static int transport_peers_valid(transport_peers *peers) {
2297 return peers->npeers;
2299 static void transport_peers_clear(struct site *st, transport_peers *peers) {
2301 transport_peers_debug(st,peers,"clear",0,0,0);
2303 static void transport_peers_copy(struct site *st, transport_peers *dst,
2304 const transport_peers *src) {
2305 dst->npeers=src->npeers;
2306 COPY_ARRAY(dst->peers, src->peers, dst->npeers);
2307 transport_peers_debug(st,dst,"copy",
2308 src->npeers, &src->peers->addr, sizeof(*src->peers));
2311 static void transport_resolve_complete(struct site *st,
2312 const struct comm_addr *addrs,
2314 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2316 transport_expire_record_peers(st,&st->setup_peers,addrs,naddrs,
2320 static void transport_resolve_complete_tardy(struct site *st,
2321 const struct comm_addr *addrs,
2323 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2324 "resolved tardily");
2327 static void transport_peers__copy_by_mask(transport_peer *out, int *nout_io,
2329 const transport_peers *inp) {
2330 /* out and in->peers may be the same region, or nonoverlapping */
2331 const transport_peer *in=inp->peers;
2333 for (slot=0; slot<inp->npeers; slot++) {
2334 if (!(mask & (1U << slot)))
2336 if (!(out==in && slot==*nout_io))
2337 COPY_OBJ(out[*nout_io], in[slot]);
2342 void transport_xmit(struct site *st, transport_peers *peers,
2343 struct buffer_if *buf, bool_t candebug) {
2345 transport_peers_expire(st, peers);
2346 unsigned failed=0; /* bitmask */
2347 assert(MAX_PEER_ADDRS < sizeof(unsigned)*CHAR_BIT);
2350 for (slot=0; slot<peers->npeers; slot++) {
2351 transport_peer *peer=&peers->peers[slot];
2353 peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr);
2355 dump_packet(st, buf, &peer->addr, False, ok);
2357 failed |= 1U << slot;
2360 if (ok && !st->peer_mobile)
2363 /* Now we need to demote/delete failing addrs: if we are mobile we
2364 * merely demote them; otherwise we delete them. */
2365 if (st->local_mobile) {
2366 unsigned expected = ((1U << nfailed)-1) << (peers->npeers-nfailed);
2367 /* `expected' has all the failures at the end already */
2368 if (failed != expected) {
2370 transport_peer failedpeers[nfailed];
2371 transport_peers__copy_by_mask(failedpeers, &fslot, failed,peers);
2372 assert(fslot == nfailed);
2374 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2375 assert(wslot+nfailed == peers->npeers);
2376 COPY_ARRAY(peers->peers+wslot, failedpeers, nfailed);
2377 transport_peers_debug(st,peers,"mobile failure reorder",0,0,0);
2380 if (failed && peers->npeers > 1) {
2382 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2383 peers->npeers=wslot;
2384 transport_peers_debug(st,peers,"non-mobile failure cleanup",0,0,0);
2389 /***** END of transport peers declarations *****/