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 */
300 bool_t local_mobile, peer_mobile; /* Mobile client support */
301 int32_t transport_peers_max;
302 string_t tunname; /* localname<->remotename by default, used in logs */
303 cstring_t *addresses; /* DNS name or address(es) for bootstrapping, optional */
304 int remoteport; /* Port for bootstrapping, optional */
306 struct netlink_if *netlink;
307 struct comm_if **comms;
309 struct resolver_if *resolver;
311 struct random_if *random;
312 struct rsaprivkey_if *privkey;
313 struct rsapubkey_if *pubkey;
314 struct transform_if **transforms;
317 struct hash_if *hash;
319 uint32_t index; /* Index of this site */
320 uint32_t local_capabilities;
321 int32_t setup_retries; /* How many times to send setup packets */
322 int32_t setup_retry_interval; /* Initial timeout for setup packets */
323 int32_t wait_timeout; /* How long to wait if setup unsuccessful */
324 int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
325 int32_t key_lifetime; /* How long a key lasts once set up */
326 int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
327 after this time, initiate a new
330 bool_t setup_priority; /* Do we have precedence if both sites emit
331 message 1 simultaneously? */
334 /* runtime information */
336 uint64_t now; /* Most recently seen time */
337 bool_t allow_send_prod;
339 int resolving_n_results_all;
340 int resolving_n_results_stored;
341 struct comm_addr resolving_results[MAX_PEER_ADDRS];
343 /* The currently established session */
344 struct data_key current;
345 struct data_key auxiliary_key;
346 bool_t auxiliary_is_new;
347 uint64_t renegotiate_key_time; /* When we can negotiate a new key */
348 uint64_t auxiliary_renegotiate_key_time;
349 transport_peers peers; /* Current address(es) of peer for data traffic */
351 /* The current key setup protocol exchange. We can only be
352 involved in one of these at a time. There's a potential for
353 denial of service here (the attacker keeps sending a setup
354 packet; we keep trying to continue the exchange, and have to
355 timeout before we can listen for another setup packet); perhaps
356 we should keep a list of 'bad' sources for setup packets. */
357 uint32_t remote_capabilities;
358 uint16_t remote_adv_mtu;
359 struct transform_if *chosen_transform;
360 uint32_t setup_session_id;
361 transport_peers setup_peers;
362 uint8_t localN[NONCELEN]; /* Nonces for key exchange */
363 uint8_t remoteN[NONCELEN];
364 struct buffer_if buffer; /* Current outgoing key exchange packet */
365 struct buffer_if scratch;
366 int32_t retries; /* Number of retries remaining */
367 uint64_t timeout; /* Timeout for current state */
369 uint8_t *sharedsecret;
370 uint32_t sharedsecretlen, sharedsecretallocd;
371 struct transform_inst_if *new_transform; /* For key setup/verify */
374 static uint32_t event_log_priority(struct site *st, uint32_t event)
376 if (!(event&st->log_events))
379 case LOG_UNEXPECTED: return M_INFO;
380 case LOG_SETUP_INIT: return M_INFO;
381 case LOG_SETUP_TIMEOUT: return M_NOTICE;
382 case LOG_ACTIVATE_KEY: return M_INFO;
383 case LOG_TIMEOUT_KEY: return M_INFO;
384 case LOG_SEC: return M_SECURITY;
385 case LOG_STATE: return M_DEBUG;
386 case LOG_DROP: return M_DEBUG;
387 case LOG_DUMP: return M_DEBUG;
388 case LOG_ERROR: return M_ERR;
389 case LOG_PEER_ADDRS: return M_DEBUG;
390 default: return M_ERR;
394 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
396 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
400 class=event_log_priority(st, event);
402 slilog_part(st->log,class,"%s: ",st->tunname);
403 vslilog_part(st->log,class,msg,ap);
404 slilog_part(st->log,class,"\n");
408 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
410 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
414 vslog(st,event,msg,ap);
418 static void logtimeout(struct site *st, const char *fmt, ...)
420 static void logtimeout(struct site *st, const char *fmt, ...)
422 uint32_t class=event_log_priority(st,LOG_SETUP_TIMEOUT);
429 slilog_part(st->log,class,"%s: ",st->tunname);
430 vslilog_part(st->log,class,fmt,ap);
434 for (i=0, delim=" (tried ";
435 i<st->setup_peers.npeers;
437 transport_peer *peer=&st->setup_peers.peers[i];
438 const char *s=comm_addr_to_string(&peer->addr);
439 slilog_part(st->log,class,"%s%s",delim,s);
442 slilog_part(st->log,class,")\n");
446 static void set_link_quality(struct site *st);
447 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
448 static void delete_one_key(struct site *st, struct data_key *key,
449 const char *reason /* may be 0 meaning don't log*/,
450 const char *which /* ignored if !reasonn */,
451 uint32_t loglevel /* ignored if !reasonn */);
452 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
453 const struct comm_addr *prod_hint);
454 static void enter_state_run(struct site *st);
455 static bool_t enter_state_resolve(struct site *st);
456 static void decrement_resolving_count(struct site *st, int by);
457 static bool_t enter_new_state(struct site *st,uint32_t next);
458 static void enter_state_wait(struct site *st);
459 static void activate_new_key(struct site *st);
461 static bool_t is_transform_valid(struct transform_inst_if *transform)
463 return transform && transform->valid(transform->st);
466 static bool_t current_valid(struct site *st)
468 return is_transform_valid(st->current.transform);
471 #define DEFINE_CALL_TRANSFORM(fwdrev) \
472 static int call_transform_##fwdrev(struct site *st, \
473 struct transform_inst_if *transform, \
474 struct buffer_if *buf, \
475 const char **errmsg) \
477 if (!is_transform_valid(transform)) { \
478 *errmsg="transform not set up"; \
481 return transform->fwdrev(transform->st,buf,errmsg); \
484 DEFINE_CALL_TRANSFORM(forwards)
485 DEFINE_CALL_TRANSFORM(reverse)
487 static void dispose_transform(struct transform_inst_if **transform_var)
489 struct transform_inst_if *transform=*transform_var;
491 transform->delkey(transform->st);
492 transform->destroy(transform->st);
497 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
498 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
499 #define CHECK_TYPE(b,t) do { uint32_t type; \
500 CHECK_AVAIL((b),4); \
501 type=buf_unprepend_uint32((b)); \
502 if (type!=(t)) return False; } while(0)
504 static _Bool type_is_msg34(uint32_t type)
507 type == LABEL_MSG3 ||
508 type == LABEL_MSG3BIS ||
515 struct buffer_if extrainfo;
522 struct parsedname remote;
523 struct parsedname local;
524 uint32_t remote_capabilities;
526 int capab_transformnum;
536 static void set_new_transform(struct site *st, char *pk)
538 /* Make room for the shared key */
539 st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
540 assert(st->sharedsecretlen);
541 if (st->sharedsecretlen > st->sharedsecretallocd) {
542 st->sharedsecretallocd=st->sharedsecretlen;
543 st->sharedsecret=safe_realloc_ary(st->sharedsecret,1,
544 st->sharedsecretallocd,
545 "site:sharedsecret");
548 /* Generate the shared key */
549 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,pk,
550 st->sharedsecret,st->sharedsecretlen);
552 /* Set up the transform */
553 struct transform_if *generator=st->chosen_transform;
554 struct transform_inst_if *generated=generator->create(generator->st);
555 generated->setkey(generated->st,st->sharedsecret,
556 st->sharedsecretlen,st->setup_priority);
557 dispose_transform(&st->new_transform);
558 st->new_transform=generated;
560 slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
561 " %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
562 st->chosen_transform->capab_transformnum,
563 st->local_capabilities, st->remote_capabilities);
567 int32_t lenpos, afternul;
569 static void append_string_xinfo_start(struct buffer_if *buf,
570 struct xinfoadd *xia,
572 /* Helps construct one of the names with additional info as found
573 * in MSG1..4. Call this function first, then append all the
574 * desired extra info (not including the nul byte) to the buffer,
575 * then call append_string_xinfo_done. */
577 xia->lenpos = buf->size;
578 buf_append_string(buf,str);
579 buf_append_uint8(buf,0);
580 xia->afternul = buf->size;
582 static void append_string_xinfo_done(struct buffer_if *buf,
583 struct xinfoadd *xia)
585 /* we just need to adjust the string length */
586 if (buf->size == xia->afternul) {
587 /* no extra info, strip the nul too */
588 buf_unappend_uint8(buf);
590 put_uint16(buf->start+xia->lenpos, buf->size-(xia->lenpos+2));
594 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
595 out using a transform of config data supplied by netlink */
596 static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what)
602 st->retries=st->setup_retries;
603 BUF_ALLOC(&st->buffer,what);
604 buffer_init(&st->buffer,0);
605 buf_append_uint32(&st->buffer,
606 (type==LABEL_MSG1?0:st->setup_session_id));
607 buf_append_uint32(&st->buffer,st->index);
608 buf_append_uint32(&st->buffer,type);
611 append_string_xinfo_start(&st->buffer,&xia,st->localname);
612 if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
613 buf_append_uint32(&st->buffer,st->local_capabilities);
615 if (type_is_msg34(type)) {
616 buf_append_uint16(&st->buffer,st->mtu_target);
618 append_string_xinfo_done(&st->buffer,&xia);
620 buf_append_string(&st->buffer,st->remotename);
621 BUF_ADD_OBJ(append,&st->buffer,st->localN);
622 if (type==LABEL_MSG1) return True;
623 BUF_ADD_OBJ(append,&st->buffer,st->remoteN);
624 if (type==LABEL_MSG2) return True;
626 if (hacky_par_mid_failnow()) return False;
628 if (type==LABEL_MSG3BIS)
629 buf_append_uint8(&st->buffer,st->chosen_transform->capab_transformnum);
631 dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
632 buf_append_string(&st->buffer,dhpub);
634 hash=safe_malloc(st->hash->len, "generate_msg");
635 hst=st->hash->init();
636 st->hash->update(hst,st->buffer.start,st->buffer.size);
637 st->hash->final(hst,hash);
638 sig=st->privkey->sign(st->privkey->st,hash,st->hash->len);
639 buf_append_string(&st->buffer,sig);
645 static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
648 nm->len=buf_unprepend_uint16(msg);
649 CHECK_AVAIL(msg,nm->len);
650 nm->name=buf_unprepend(msg,nm->len);
651 uint8_t *nul=memchr(nm->name,0,nm->len);
653 buffer_readonly_view(&nm->extrainfo,0,0);
655 buffer_readonly_view(&nm->extrainfo, nul+1, msg->start-(nul+1));
656 nm->len=nul-nm->name;
661 static bool_t unpick_msg(struct site *st, uint32_t type,
662 struct buffer_if *msg, struct msg *m)
664 m->capab_transformnum=-1;
665 m->hashstart=msg->start;
667 m->dest=buf_unprepend_uint32(msg);
669 m->source=buf_unprepend_uint32(msg);
670 CHECK_TYPE(msg,type);
671 if (!unpick_name(msg,&m->remote)) return False;
672 m->remote_capabilities=0;
674 if (m->remote.extrainfo.size) {
675 CHECK_AVAIL(&m->remote.extrainfo,4);
676 m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
678 if (type_is_msg34(type) && m->remote.extrainfo.size) {
679 CHECK_AVAIL(&m->remote.extrainfo,2);
680 m->remote_mtu=buf_unprepend_uint16(&m->remote.extrainfo);
682 if (!unpick_name(msg,&m->local)) return False;
683 if (type==LABEL_PROD) {
687 CHECK_AVAIL(msg,NONCELEN);
688 m->nR=buf_unprepend(msg,NONCELEN);
689 if (type==LABEL_MSG1) {
693 CHECK_AVAIL(msg,NONCELEN);
694 m->nL=buf_unprepend(msg,NONCELEN);
695 if (type==LABEL_MSG2) {
699 if (type==LABEL_MSG3BIS) {
701 m->capab_transformnum = buf_unprepend_uint8(msg);
703 m->capab_transformnum = CAPAB_TRANSFORMNUM_ANCIENT;
706 m->pklen=buf_unprepend_uint16(msg);
707 CHECK_AVAIL(msg,m->pklen);
708 m->pk=buf_unprepend(msg,m->pklen);
709 m->hashlen=msg->start-m->hashstart;
711 m->siglen=buf_unprepend_uint16(msg);
712 CHECK_AVAIL(msg,m->siglen);
713 m->sig=buf_unprepend(msg,m->siglen);
718 static bool_t name_matches(const struct parsedname *nm, const char *expected)
720 int expected_len=strlen(expected);
722 nm->len == expected_len &&
723 !memcmp(nm->name, expected, expected_len);
726 static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
729 if (type==LABEL_MSG1) return True;
731 /* Check that the site names and our nonce have been sent
732 back correctly, and then store our peer's nonce. */
733 if (!name_matches(&m->remote,st->remotename)) {
734 *error="wrong remote site name";
737 if (!name_matches(&m->local,st->localname)) {
738 *error="wrong local site name";
741 if (memcmp(m->nL,st->localN,NONCELEN)!=0) {
742 *error="wrong locally-generated nonce";
745 if (type==LABEL_MSG2) return True;
746 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
747 *error="wrong remotely-generated nonce";
750 /* MSG3 has complicated rules about capabilities, which are
751 * handled in process_msg3. */
752 if (type==LABEL_MSG3 || type==LABEL_MSG3BIS) return True;
753 if (m->remote_capabilities!=st->remote_capabilities) {
754 *error="remote capabilities changed";
757 if (type==LABEL_MSG4) return True;
758 *error="unknown message type";
762 static bool_t generate_msg1(struct site *st)
764 st->random->generate(st->random->st,NONCELEN,st->localN);
765 return generate_msg(st,LABEL_MSG1,"site:MSG1");
768 static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
769 const struct comm_addr *src, struct msg *m)
771 /* We've already determined we're in an appropriate state to
772 process an incoming MSG1, and that the MSG1 has correct values
775 st->setup_session_id=m->source;
776 st->remote_capabilities=m->remote_capabilities;
777 memcpy(st->remoteN,m->nR,NONCELEN);
781 static bool_t generate_msg2(struct site *st)
783 st->random->generate(st->random->st,NONCELEN,st->localN);
784 return generate_msg(st,LABEL_MSG2,"site:MSG2");
787 static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
788 const struct comm_addr *src)
793 if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False;
794 if (!check_msg(st,LABEL_MSG2,&m,&err)) {
795 slog(st,LOG_SEC,"msg2: %s",err);
798 st->setup_session_id=m.source;
799 st->remote_capabilities=m.remote_capabilities;
801 /* Select the transform to use */
803 uint32_t remote_transforms = st->remote_capabilities & CAPAB_TRANSFORM_MASK;
804 if (!remote_transforms)
805 /* old secnets only had this one transform */
806 remote_transforms = 1UL << CAPAB_TRANSFORMNUM_ANCIENT;
808 struct transform_if *ti;
810 for (i=0; i<st->ntransforms; i++) {
811 ti=st->transforms[i];
812 if ((1UL << ti->capab_transformnum) & remote_transforms)
813 goto transform_found;
815 slog(st,LOG_ERROR,"no transforms in common"
816 " (us %#"PRIx32"; them: %#"PRIx32")",
817 st->local_capabilities & CAPAB_TRANSFORM_MASK,
821 st->chosen_transform=ti;
823 memcpy(st->remoteN,m.nR,NONCELEN);
827 static bool_t generate_msg3(struct site *st)
829 /* Now we have our nonce and their nonce. Think of a secret key,
830 and create message number 3. */
831 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
832 return generate_msg(st,
833 (st->remote_capabilities & CAPAB_TRANSFORM_MASK
834 ? LABEL_MSG3BIS : LABEL_MSG3),
838 static bool_t process_msg3_msg4(struct site *st, struct msg *m)
843 /* Check signature and store g^x mod m */
844 hash=safe_malloc(st->hash->len, "process_msg3_msg4");
845 hst=st->hash->init();
846 st->hash->update(hst,m->hashstart,m->hashlen);
847 st->hash->final(hst,hash);
848 /* Terminate signature with a '0' - cheating, but should be ok */
850 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m->sig)) {
851 slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
857 st->remote_adv_mtu=m->remote_mtu;
862 static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
863 const struct comm_addr *src, uint32_t msgtype)
868 assert(msgtype==LABEL_MSG3 || msgtype==LABEL_MSG3BIS);
870 if (!unpick_msg(st,msgtype,msg3,&m)) return False;
871 if (!check_msg(st,msgtype,&m,&err)) {
872 slog(st,LOG_SEC,"msg3: %s",err);
875 uint32_t capab_adv_late = m.remote_capabilities
876 & ~st->remote_capabilities & CAPAB_EARLY;
877 if (capab_adv_late) {
878 slog(st,LOG_SEC,"msg3 impermissibly adds early capability flag(s)"
879 " %#"PRIx32" (was %#"PRIx32", now %#"PRIx32")",
880 capab_adv_late, st->remote_capabilities, m.remote_capabilities);
883 st->remote_capabilities|=m.remote_capabilities;
885 struct transform_if *ti;
887 for (i=0; i<st->ntransforms; i++) {
888 ti=st->transforms[i];
889 if (ti->capab_transformnum == m.capab_transformnum)
890 goto transform_found;
892 slog(st,LOG_SEC,"peer chose unknown-to-us transform %d!",
893 m.capab_transformnum);
896 st->chosen_transform=ti;
898 if (!process_msg3_msg4(st,&m))
901 /* Terminate their DH public key with a '0' */
903 /* Invent our DH secret key */
904 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
906 /* Generate the shared key and set up the transform */
907 set_new_transform(st,m.pk);
912 static bool_t generate_msg4(struct site *st)
914 /* We have both nonces, their public key and our private key. Generate
915 our public key, sign it and send it to them. */
916 return generate_msg(st,LABEL_MSG4,"site:MSG4");
919 static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
920 const struct comm_addr *src)
925 if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
926 if (!check_msg(st,LABEL_MSG4,&m,&err)) {
927 slog(st,LOG_SEC,"msg4: %s",err);
931 if (!process_msg3_msg4(st,&m))
934 /* Terminate their DH public key with a '0' */
937 /* Generate the shared key and set up the transform */
938 set_new_transform(st,m.pk);
949 static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0,
953 m->dest=buf_unprepend_uint32(msg0);
955 m->source=buf_unprepend_uint32(msg0);
957 m->type=buf_unprepend_uint32(msg0);
959 /* Leaves transformed part of buffer untouched */
962 static bool_t generate_msg5(struct site *st)
964 cstring_t transform_err;
966 BUF_ALLOC(&st->buffer,"site:MSG5");
967 /* We are going to add four words to the message */
968 buffer_init(&st->buffer,calculate_max_start_pad());
969 /* Give the netlink code an opportunity to put its own stuff in the
970 message (configuration information, etc.) */
971 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
972 if (call_transform_forwards(st,st->new_transform,
973 &st->buffer,&transform_err))
975 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
976 buf_prepend_uint32(&st->buffer,st->index);
977 buf_prepend_uint32(&st->buffer,st->setup_session_id);
979 st->retries=st->setup_retries;
983 static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
984 const struct comm_addr *src,
985 struct transform_inst_if *transform)
988 cstring_t transform_err;
990 if (!unpick_msg0(st,msg5,&m)) return False;
992 if (call_transform_reverse(st,transform,msg5,&transform_err)) {
993 /* There's a problem */
994 slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
997 /* Buffer should now contain untransformed PING packet data */
999 if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) {
1000 slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
1003 /* Older versions of secnet used to write some config data here
1004 * which we ignore. So we don't CHECK_EMPTY */
1008 static void create_msg6(struct site *st, struct transform_inst_if *transform,
1009 uint32_t session_id)
1011 cstring_t transform_err;
1013 BUF_ALLOC(&st->buffer,"site:MSG6");
1014 /* We are going to add four words to the message */
1015 buffer_init(&st->buffer,calculate_max_start_pad());
1016 /* Give the netlink code an opportunity to put its own stuff in the
1017 message (configuration information, etc.) */
1018 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1019 int problem = call_transform_forwards(st,transform,
1020 &st->buffer,&transform_err);
1022 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1023 buf_prepend_uint32(&st->buffer,st->index);
1024 buf_prepend_uint32(&st->buffer,session_id);
1027 static bool_t generate_msg6(struct site *st)
1029 if (!is_transform_valid(st->new_transform))
1031 create_msg6(st,st->new_transform,st->setup_session_id);
1032 st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
1036 static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
1037 const struct comm_addr *src)
1040 cstring_t transform_err;
1042 if (!unpick_msg0(st,msg6,&m)) return False;
1044 if (call_transform_reverse(st,st->new_transform,msg6,&transform_err)) {
1045 /* There's a problem */
1046 slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
1049 /* Buffer should now contain untransformed PING packet data */
1050 CHECK_AVAIL(msg6,4);
1051 if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) {
1052 slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
1055 /* Older versions of secnet used to write some config data here
1056 * which we ignore. So we don't CHECK_EMPTY */
1060 static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
1061 const struct comm_addr *src)
1063 cstring_t transform_err, auxkey_err, newkey_err="n/a";
1067 if (!unpick_msg0(st,msg0,&m)) return False;
1069 /* Keep a copy so we can try decrypting it with multiple keys */
1070 buffer_copy(&st->scratch, msg0);
1072 problem = call_transform_reverse(st,st->current.transform,
1073 msg0,&transform_err);
1075 if (!st->auxiliary_is_new)
1076 delete_one_key(st,&st->auxiliary_key,
1077 "peer has used new key","auxiliary key",LOG_SEC);
1083 buffer_copy(msg0, &st->scratch);
1084 problem = call_transform_reverse(st,st->auxiliary_key.transform,
1087 slog(st,LOG_DROP,"processing packet which uses auxiliary key");
1088 if (st->auxiliary_is_new) {
1089 /* We previously timed out in state SENTMSG5 but it turns
1090 * out that our peer did in fact get our MSG5 and is
1091 * using the new key. So we should switch to it too. */
1092 /* This is a bit like activate_new_key. */
1095 st->current=st->auxiliary_key;
1096 st->auxiliary_key=t;
1098 delete_one_key(st,&st->auxiliary_key,"peer has used new key",
1099 "previous key",LOG_SEC);
1100 st->auxiliary_is_new=0;
1101 st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
1108 if (st->state==SITE_SENTMSG5) {
1109 buffer_copy(msg0, &st->scratch);
1110 problem = call_transform_reverse(st,st->new_transform,
1113 /* It looks like we didn't get the peer's MSG6 */
1114 /* This is like a cut-down enter_new_state(SITE_RUN) */
1115 slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
1116 BUF_FREE(&st->buffer);
1118 activate_new_key(st);
1119 return True; /* do process the data in this packet */
1125 slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
1126 transform_err,auxkey_err,newkey_err);
1127 initiate_key_setup(st,"incoming message would not decrypt",0);
1128 send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
1132 slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
1136 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
1137 const struct comm_addr *src)
1141 if (!decrypt_msg0(st,msg0,src))
1144 CHECK_AVAIL(msg0,4);
1145 type=buf_unprepend_uint32(msg0);
1148 /* We must forget about the current session. */
1149 delete_keys(st,"request from peer",LOG_SEC);
1150 /* probably, the peer is shutting down, and this is going to fail,
1151 * but we need to be trying to bring the link up again */
1153 initiate_key_setup(st,"peer requested key teardown",0);
1156 /* Deliver to netlink layer */
1157 st->netlink->deliver(st->netlink->st,msg0);
1158 transport_data_msgok(st,src);
1159 /* See whether we should start negotiating a new key */
1160 if (st->now > st->renegotiate_key_time)
1161 initiate_key_setup(st,"incoming packet in renegotiation window",0);
1164 slog(st,LOG_SEC,"incoming encrypted message of type %08x "
1171 static void dump_packet(struct site *st, struct buffer_if *buf,
1172 const struct comm_addr *addr, bool_t incoming,
1175 uint32_t dest=get_uint32(buf->start);
1176 uint32_t source=get_uint32(buf->start+4);
1177 uint32_t msgtype=get_uint32(buf->start+8);
1179 if (st->log_events & LOG_DUMP)
1180 slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x: %s%s",
1181 st->tunname,incoming?"incoming":"outgoing",
1182 dest,source,msgtype,comm_addr_to_string(addr),
1186 static bool_t comm_addr_sendmsg(struct site *st,
1187 const struct comm_addr *dest,
1188 struct buffer_if *buf)
1190 return dest->comm->sendmsg(dest->comm->st, buf, dest, 0);
1193 static uint32_t site_status(void *st)
1198 static bool_t send_msg(struct site *st)
1200 if (st->retries>0) {
1201 transport_xmit(st, &st->setup_peers, &st->buffer, True);
1202 st->timeout=st->now+st->setup_retry_interval;
1205 } else if (st->state==SITE_SENTMSG5) {
1206 logtimeout(st,"timed out sending MSG5, stashing new key");
1207 /* We stash the key we have produced, in case it turns out that
1208 * our peer did see our MSG5 after all and starts using it. */
1209 /* This is a bit like some of activate_new_key */
1210 struct transform_inst_if *t;
1211 t=st->auxiliary_key.transform;
1212 st->auxiliary_key.transform=st->new_transform;
1213 st->new_transform=t;
1214 dispose_transform(&st->new_transform);
1216 st->auxiliary_is_new=1;
1217 st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
1218 st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
1219 st->auxiliary_key.remote_session_id=st->setup_session_id;
1221 enter_state_wait(st);
1224 logtimeout(st,"timed out sending key setup packet "
1225 "(in state %s)",state_name(st->state));
1226 enter_state_wait(st);
1231 static void site_resolve_callback(void *sst, const struct comm_addr *addrs,
1232 int stored_naddrs, int all_naddrs,
1233 const char *address, const char *failwhy)
1235 struct site *st=sst;
1237 if (!stored_naddrs) {
1238 slog(st,LOG_ERROR,"resolution of %s failed: %s",address,failwhy);
1240 slog(st,LOG_PEER_ADDRS,"resolution of %s completed, %d addrs, eg: %s",
1241 address, all_naddrs, comm_addr_to_string(&addrs[0]));;
1243 int space=st->transport_peers_max-st->resolving_n_results_stored;
1244 int n_tocopy=MIN(stored_naddrs,space);
1245 COPY_ARRAY(st->resolving_results + st->resolving_n_results_stored,
1248 st->resolving_n_results_stored += n_tocopy;
1249 st->resolving_n_results_all += all_naddrs;
1252 decrement_resolving_count(st,1);
1255 static void decrement_resolving_count(struct site *st, int by)
1257 assert(st->resolving_count>0);
1258 st->resolving_count-=by;
1260 if (st->resolving_count)
1263 /* OK, we are done with them all. Handle combined results. */
1265 const struct comm_addr *addrs=st->resolving_results;
1266 int naddrs=st->resolving_n_results_stored;
1267 assert(naddrs<=st->transport_peers_max);
1270 if (naddrs != st->resolving_n_results_all) {
1271 slog(st,LOG_SETUP_INIT,"resolution of supplied addresses/names"
1272 " yielded too many results (%d > %d), some ignored",
1273 st->resolving_n_results_all, naddrs);
1275 slog(st,LOG_STATE,"resolution completed, %d addrs, eg: %s",
1276 naddrs, iaddr_to_string(&addrs[0].ia));;
1279 switch (st->state) {
1281 if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) {
1282 enter_new_state(st,SITE_SENTMSG1);
1284 /* Can't figure out who to try to to talk to */
1285 slog(st,LOG_SETUP_INIT,
1286 "key exchange failed: cannot find peer address");
1287 enter_state_run(st);
1290 case SITE_SENTMSG1: case SITE_SENTMSG2:
1291 case SITE_SENTMSG3: case SITE_SENTMSG4:
1294 /* We start using the address immediately for data too.
1295 * It's best to store it in st->peers now because we might
1296 * go via SENTMSG5, WAIT, and a MSG0, straight into using
1297 * the new key (without updating the data peer addrs). */
1298 transport_resolve_complete(st,addrs,naddrs);
1299 } else if (st->local_mobile) {
1300 /* We can't let this rest because we may have a peer
1301 * address which will break in the future. */
1302 slog(st,LOG_SETUP_INIT,"resolution failed: "
1303 "abandoning key exchange");
1304 enter_state_wait(st);
1306 slog(st,LOG_SETUP_INIT,"resolution failed: "
1307 " continuing to use source address of peer's packets"
1308 " for key exchange and ultimately data");
1313 slog(st,LOG_SETUP_INIT,"resolution completed tardily,"
1314 " updating peer address(es)");
1315 transport_resolve_complete_tardy(st,addrs,naddrs);
1316 } else if (st->local_mobile) {
1317 /* Not very good. We should queue (another) renegotiation
1318 * so that we can update the peer address. */
1319 st->key_renegotiate_time=st->now+st->wait_timeout;
1321 slog(st,LOG_SETUP_INIT,"resolution failed: "
1322 " continuing to use source address of peer's packets");
1332 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
1333 const struct comm_addr *prod_hint)
1335 /* Reentrancy hazard: can call enter_new_state/enter_state_* */
1336 if (st->state!=SITE_RUN) return False;
1337 slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
1338 if (st->addresses) {
1339 slog(st,LOG_SETUP_INIT,"resolving peer address(es)");
1340 return enter_state_resolve(st);
1341 } else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) {
1342 return enter_new_state(st,SITE_SENTMSG1);
1344 slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
1348 static void activate_new_key(struct site *st)
1350 struct transform_inst_if *t;
1352 /* We have three transform instances, which we swap between old,
1354 t=st->auxiliary_key.transform;
1355 st->auxiliary_key.transform=st->current.transform;
1356 st->current.transform=st->new_transform;
1357 st->new_transform=t;
1358 dispose_transform(&st->new_transform);
1361 st->auxiliary_is_new=0;
1362 st->auxiliary_key.key_timeout=st->current.key_timeout;
1363 st->current.key_timeout=st->now+st->key_lifetime;
1364 st->renegotiate_key_time=st->now+st->key_renegotiate_time;
1365 transport_peers_copy(st,&st->peers,&st->setup_peers);
1366 st->current.remote_session_id=st->setup_session_id;
1368 /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
1369 * But their mtu be unspecified, in which case we just use ours. */
1370 uint32_t intersite_mtu=
1371 MIN(st->mtu_target, st->remote_adv_mtu ?: ~(uint32_t)0);
1372 st->netlink->set_mtu(st->netlink->st,intersite_mtu);
1374 slog(st,LOG_ACTIVATE_KEY,"new key activated"
1375 " (mtu ours=%"PRId32" theirs=%"PRId32" intersite=%"PRId32")",
1376 st->mtu_target, st->remote_adv_mtu, intersite_mtu);
1377 enter_state_run(st);
1380 static void delete_one_key(struct site *st, struct data_key *key,
1381 cstring_t reason, cstring_t which, uint32_t loglevel)
1383 if (!is_transform_valid(key->transform)) return;
1384 if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
1385 dispose_transform(&key->transform);
1389 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
1391 if (current_valid(st)) {
1392 slog(st,loglevel,"session closed (%s)",reason);
1394 delete_one_key(st,&st->current,0,0,0);
1395 set_link_quality(st);
1397 delete_one_key(st,&st->auxiliary_key,0,0,0);
1400 static void state_assert(struct site *st, bool_t ok)
1402 if (!ok) fatal("site:state_assert");
1405 static void enter_state_stop(struct site *st)
1407 st->state=SITE_STOP;
1409 delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
1410 dispose_transform(&st->new_transform);
1413 static void set_link_quality(struct site *st)
1416 if (current_valid(st))
1417 quality=LINK_QUALITY_UP;
1418 else if (st->state==SITE_WAIT || st->state==SITE_STOP)
1419 quality=LINK_QUALITY_DOWN;
1420 else if (st->addresses)
1421 quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
1422 else if (transport_peers_valid(&st->peers))
1423 quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
1425 quality=LINK_QUALITY_DOWN;
1427 st->netlink->set_quality(st->netlink->st,quality);
1430 static void enter_state_run(struct site *st)
1432 slog(st,LOG_STATE,"entering state RUN");
1436 st->setup_session_id=0;
1437 transport_peers_clear(st,&st->setup_peers);
1438 FILLZERO(st->localN);
1439 FILLZERO(st->remoteN);
1440 dispose_transform(&st->new_transform);
1441 memset(st->dhsecret,0,st->dh->len);
1442 memset(st->sharedsecret,0,st->sharedsecretlen);
1443 set_link_quality(st);
1445 if (st->keepalive && !current_valid(st))
1446 initiate_key_setup(st, "keepalive", 0);
1449 static bool_t ensure_resolving(struct site *st)
1451 /* Reentrancy hazard: may call site_resolve_callback and hence
1452 * enter_new_state, enter_state_* and generate_msg*. */
1453 if (st->resolving_count)
1456 assert(st->addresses);
1458 /* resolver->request might reentrantly call site_resolve_callback
1459 * which will decrement st->resolving, so we need to increment it
1460 * twice beforehand to prevent decrement from thinking we're
1461 * finished, and decrement it ourselves. Alternatively if
1462 * everything fails then there are no callbacks due and we simply
1463 * set it to 0 and return false.. */
1464 st->resolving_n_results_stored=0;
1465 st->resolving_n_results_all=0;
1466 st->resolving_count+=2;
1467 const char **addrp=st->addresses;
1468 const char *address;
1470 for (; (address=*addrp++); ) {
1471 bool_t ok = st->resolver->request(st->resolver->st,address,
1472 st->remoteport,st->comms[0],
1473 site_resolve_callback,st);
1475 st->resolving_count++;
1479 st->resolving_count=0;
1482 decrement_resolving_count(st,2);
1486 static bool_t enter_state_resolve(struct site *st)
1488 /* Reentrancy hazard! See ensure_resolving. */
1489 state_assert(st,st->state==SITE_RUN);
1490 slog(st,LOG_STATE,"entering state RESOLVE");
1491 st->state=SITE_RESOLVE;
1492 return ensure_resolving(st);
1495 static bool_t enter_new_state(struct site *st, uint32_t next)
1497 bool_t (*gen)(struct site *st);
1500 slog(st,LOG_STATE,"entering state %s",state_name(next));
1503 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
1507 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1508 st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
1512 state_assert(st,st->state==SITE_SENTMSG1);
1513 BUF_FREE(&st->buffer);
1517 state_assert(st,st->state==SITE_SENTMSG2);
1518 BUF_FREE(&st->buffer);
1522 state_assert(st,st->state==SITE_SENTMSG3);
1523 BUF_FREE(&st->buffer);
1527 state_assert(st,st->state==SITE_SENTMSG4);
1528 BUF_FREE(&st->buffer);
1533 fatal("enter_new_state(%s): invalid new state",state_name(next));
1537 if (hacky_par_start_failnow()) return False;
1539 r= gen(st) && send_msg(st);
1542 st->setup_retries, st->setup_retry_interval,
1547 if (next==SITE_RUN) {
1548 BUF_FREE(&st->buffer); /* Never reused */
1549 st->timeout=0; /* Never retransmit */
1550 activate_new_key(st);
1554 slog(st,LOG_ERROR,"error entering state %s",state_name(next));
1555 st->buffer.free=False; /* Unconditionally use the buffer; it may be
1556 in either state, and enter_state_wait() will
1558 enter_state_wait(st);
1562 /* msg7 tells our peer that we're about to forget our key */
1563 static bool_t send_msg7(struct site *st, cstring_t reason)
1565 cstring_t transform_err;
1567 if (current_valid(st) && st->buffer.free
1568 && transport_peers_valid(&st->peers)) {
1569 BUF_ALLOC(&st->buffer,"site:MSG7");
1570 buffer_init(&st->buffer,calculate_max_start_pad());
1571 buf_append_uint32(&st->buffer,LABEL_MSG7);
1572 buf_append_string(&st->buffer,reason);
1573 if (call_transform_forwards(st, st->current.transform,
1574 &st->buffer, &transform_err))
1576 buf_prepend_uint32(&st->buffer,LABEL_MSG0);
1577 buf_prepend_uint32(&st->buffer,st->index);
1578 buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
1579 transport_xmit(st,&st->peers,&st->buffer,True);
1580 BUF_FREE(&st->buffer);
1587 /* We go into this state if our peer becomes uncommunicative. Similar to
1588 the "stop" state, we forget all session keys for a while, before
1589 re-entering the "run" state. */
1590 static void enter_state_wait(struct site *st)
1592 slog(st,LOG_STATE,"entering state WAIT");
1593 st->timeout=st->now+st->wait_timeout;
1594 st->state=SITE_WAIT;
1595 set_link_quality(st);
1596 BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
1597 /* XXX Erase keys etc. */
1600 static void generate_prod(struct site *st, struct buffer_if *buf)
1603 buf_append_uint32(buf,0);
1604 buf_append_uint32(buf,0);
1605 buf_append_uint32(buf,LABEL_PROD);
1606 buf_append_string(buf,st->localname);
1607 buf_append_string(buf,st->remotename);
1610 static void generate_send_prod(struct site *st,
1611 const struct comm_addr *source)
1613 if (!st->allow_send_prod) return; /* too soon */
1614 if (!(st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1615 st->state==SITE_WAIT)) return; /* we'd ignore peer's MSG1 */
1617 slog(st,LOG_SETUP_INIT,"prodding peer for key exchange");
1618 st->allow_send_prod=0;
1619 generate_prod(st,&st->scratch);
1620 bool_t ok = comm_addr_sendmsg(st, source, &st->scratch);
1621 dump_packet(st,&st->scratch,source,False,ok);
1624 static inline void site_settimeout(uint64_t timeout, int *timeout_io)
1627 int64_t offset=timeout-*now;
1628 if (offset<0) offset=0;
1629 if (offset>INT_MAX) offset=INT_MAX;
1630 if (*timeout_io<0 || offset<*timeout_io)
1635 static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
1638 struct site *st=sst;
1640 BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
1643 /* Work out when our next timeout is. The earlier of 'timeout' or
1644 'current.key_timeout'. A stored value of '0' indicates no timeout
1646 site_settimeout(st->timeout, timeout_io);
1647 site_settimeout(st->current.key_timeout, timeout_io);
1648 site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
1650 return 0; /* success */
1653 static void check_expiry(struct site *st, struct data_key *key,
1656 if (key->key_timeout && *now>key->key_timeout) {
1657 delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
1661 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1662 static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
1664 struct site *st=sst;
1667 if (st->timeout && *now>st->timeout) {
1669 if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) {
1670 if (!hacky_par_start_failnow())
1672 } else if (st->state==SITE_WAIT) {
1673 enter_state_run(st);
1675 slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d",
1679 check_expiry(st,&st->current,"current key");
1680 check_expiry(st,&st->auxiliary_key,"auxiliary key");
1683 /* This function is called by the netlink device to deliver packets
1684 intended for the remote network. The packet is in "raw" wire
1685 format, but is guaranteed to be word-aligned. */
1686 static void site_outgoing(void *sst, struct buffer_if *buf)
1688 struct site *st=sst;
1689 cstring_t transform_err;
1691 if (st->state==SITE_STOP) {
1696 st->allow_send_prod=1;
1698 /* In all other states we consider delivering the packet if we have
1699 a valid key and a valid address to send it to. */
1700 if (current_valid(st) && transport_peers_valid(&st->peers)) {
1701 /* Transform it and send it */
1703 buf_prepend_uint32(buf,LABEL_MSG9);
1704 if (call_transform_forwards(st, st->current.transform,
1705 buf, &transform_err))
1707 buf_prepend_uint32(buf,LABEL_MSG0);
1708 buf_prepend_uint32(buf,st->index);
1709 buf_prepend_uint32(buf,st->current.remote_session_id);
1710 transport_xmit(st,&st->peers,buf,False);
1717 slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size);
1719 initiate_key_setup(st,"outgoing packet",0);
1722 static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
1723 uint32_t type, struct msg *m)
1724 /* For packets which are identified by the local and remote names.
1725 * If it has our name and our peer's name in it it's for us. */
1727 struct buffer_if buf[1];
1728 buffer_readonly_clone(buf,buf_in);
1729 return unpick_msg(st,type,buf,m)
1730 && name_matches(&m->remote,st->remotename)
1731 && name_matches(&m->local,st->localname);
1734 /* This function is called by the communication device to deliver
1735 packets from our peers.
1736 It should return True if the packet is recognised as being for
1737 this current site instance (and should therefore not be processed
1738 by other sites), even if the packet was otherwise ignored. */
1739 static bool_t site_incoming(void *sst, struct buffer_if *buf,
1740 const struct comm_addr *source)
1742 struct site *st=sst;
1744 if (buf->size < 12) return False;
1746 uint32_t dest=get_uint32(buf->start);
1747 uint32_t msgtype=get_uint32(buf->start+8);
1748 struct msg named_msg;
1750 if (msgtype==LABEL_MSG1) {
1751 if (!named_for_us(st,buf,msgtype,&named_msg))
1753 /* It's a MSG1 addressed to us. Decide what to do about it. */
1754 dump_packet(st,buf,source,True,True);
1755 if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1756 st->state==SITE_WAIT) {
1757 /* We should definitely process it */
1758 transport_compute_setupinit_peers(st,0,0,source);
1759 if (process_msg1(st,buf,source,&named_msg)) {
1760 slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
1761 bool_t entered=enter_new_state(st,SITE_SENTMSG2);
1762 if (entered && st->addresses && st->local_mobile)
1763 /* We must do this as the very last thing, because
1764 the resolver callback might reenter us. */
1765 ensure_resolving(st);
1767 slog(st,LOG_ERROR,"failed to process incoming msg1");
1771 } else if (st->state==SITE_SENTMSG1) {
1772 /* We've just sent a message 1! They may have crossed on
1773 the wire. If we have priority then we ignore the
1774 incoming one, otherwise we process it as usual. */
1775 if (st->setup_priority) {
1777 slog(st,LOG_DUMP,"crossed msg1s; we are higher "
1778 "priority => ignore incoming msg1");
1781 slog(st,LOG_DUMP,"crossed msg1s; we are lower "
1782 "priority => use incoming msg1");
1783 if (process_msg1(st,buf,source,&named_msg)) {
1784 BUF_FREE(&st->buffer); /* Free our old message 1 */
1785 transport_setup_msgok(st,source);
1786 enter_new_state(st,SITE_SENTMSG2);
1788 slog(st,LOG_ERROR,"failed to process an incoming "
1789 "crossed msg1 (we have low priority)");
1795 /* The message 1 was received at an unexpected stage of the
1796 key setup. XXX POLICY - what do we do? */
1797 slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
1801 if (msgtype==LABEL_PROD) {
1802 if (!named_for_us(st,buf,msgtype,&named_msg))
1804 dump_packet(st,buf,source,True,True);
1805 if (st->state!=SITE_RUN) {
1806 slog(st,LOG_DROP,"ignoring PROD when not in state RUN");
1807 } else if (current_valid(st)) {
1808 slog(st,LOG_DROP,"ignoring PROD when we think we have a key");
1810 initiate_key_setup(st,"peer sent PROD packet",source);
1815 if (dest==st->index) {
1816 /* Explicitly addressed to us */
1817 if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True,True);
1820 /* If the source is our current peer then initiate a key setup,
1821 because our peer's forgotten the key */
1822 if (get_uint32(buf->start+4)==st->current.remote_session_id) {
1824 initiated = initiate_key_setup(st,"received a NAK",source);
1825 if (!initiated) generate_send_prod(st,source);
1827 slog(st,LOG_SEC,"bad incoming NAK");
1831 process_msg0(st,buf,source);
1834 /* Setup packet: should not have been explicitly addressed
1836 slog(st,LOG_SEC,"incoming explicitly addressed msg1");
1839 /* Setup packet: expected only in state SENTMSG1 */
1840 if (st->state!=SITE_SENTMSG1) {
1841 slog(st,LOG_UNEXPECTED,"unexpected MSG2");
1842 } else if (process_msg2(st,buf,source)) {
1843 transport_setup_msgok(st,source);
1844 enter_new_state(st,SITE_SENTMSG3);
1846 slog(st,LOG_SEC,"invalid MSG2");
1851 /* Setup packet: expected only in state SENTMSG2 */
1852 if (st->state!=SITE_SENTMSG2) {
1853 slog(st,LOG_UNEXPECTED,"unexpected MSG3");
1854 } else if (process_msg3(st,buf,source,msgtype)) {
1855 transport_setup_msgok(st,source);
1856 enter_new_state(st,SITE_SENTMSG4);
1858 slog(st,LOG_SEC,"invalid MSG3");
1862 /* Setup packet: expected only in state SENTMSG3 */
1863 if (st->state!=SITE_SENTMSG3) {
1864 slog(st,LOG_UNEXPECTED,"unexpected MSG4");
1865 } else if (process_msg4(st,buf,source)) {
1866 transport_setup_msgok(st,source);
1867 enter_new_state(st,SITE_SENTMSG5);
1869 slog(st,LOG_SEC,"invalid MSG4");
1873 /* Setup packet: expected only in state SENTMSG4 */
1874 /* (may turn up in state RUN if our return MSG6 was lost
1875 and the new key has already been activated. In that
1876 case we discard it. The peer will realise that we
1877 are using the new key when they see our data packets.
1878 Until then the peer's data packets to us get discarded. */
1879 if (st->state==SITE_SENTMSG4) {
1880 if (process_msg5(st,buf,source,st->new_transform)) {
1881 transport_setup_msgok(st,source);
1882 enter_new_state(st,SITE_RUN);
1884 slog(st,LOG_SEC,"invalid MSG5");
1886 } else if (st->state==SITE_RUN) {
1887 if (process_msg5(st,buf,source,st->current.transform)) {
1888 slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
1889 transport_setup_msgok(st,source);
1890 create_msg6(st,st->current.transform,
1891 st->current.remote_session_id);
1892 transport_xmit(st,&st->peers,&st->buffer,True);
1893 BUF_FREE(&st->buffer);
1895 slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
1898 slog(st,LOG_UNEXPECTED,"unexpected MSG5");
1902 /* Setup packet: expected only in state SENTMSG5 */
1903 if (st->state!=SITE_SENTMSG5) {
1904 slog(st,LOG_UNEXPECTED,"unexpected MSG6");
1905 } else if (process_msg6(st,buf,source)) {
1906 BUF_FREE(&st->buffer); /* Free message 5 */
1907 transport_setup_msgok(st,source);
1908 activate_new_key(st);
1910 slog(st,LOG_SEC,"invalid MSG6");
1914 slog(st,LOG_SEC,"received message of unknown type 0x%08x",
1925 static void site_control(void *vst, bool_t run)
1927 struct site *st=vst;
1928 if (run) enter_state_run(st);
1929 else enter_state_stop(st);
1932 static void site_phase_hook(void *sst, uint32_t newphase)
1934 struct site *st=sst;
1936 /* The program is shutting down; tell our peer */
1937 send_msg7(st,"shutting down");
1940 static void site_childpersist_clearkeys(void *sst, uint32_t newphase)
1942 struct site *st=sst;
1943 dispose_transform(&st->current.transform);
1944 dispose_transform(&st->auxiliary_key.transform);
1945 dispose_transform(&st->new_transform);
1946 /* Not much point overwiting the signing key, since we loaded it
1947 from disk, and it is only valid prospectively if at all,
1949 /* XXX it would be best to overwrite the DH state, because that
1950 _is_ relevant to forward secrecy. However we have no
1951 convenient interface for doing that and in practice gmp has
1952 probably dribbled droppings all over the malloc arena. A good
1953 way to fix this would be to have a privsep child for asymmetric
1954 crypto operations, but that's a task for another day. */
1957 static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
1960 static uint32_t index_sequence;
1968 st->cl.description="site";
1969 st->cl.type=CL_SITE;
1971 st->cl.interface=&st->ops;
1973 st->ops.control=site_control;
1974 st->ops.status=site_status;
1976 /* First parameter must be a dict */
1977 item=list_elem(args,0);
1978 if (!item || item->type!=t_dict)
1979 cfgfatal(loc,"site","parameter must be a dictionary\n");
1981 dict=item->data.dict;
1982 st->localname=dict_read_string(dict, "local-name", True, "site", loc);
1983 st->remotename=dict_read_string(dict, "name", True, "site", loc);
1985 st->keepalive=dict_read_bool(dict,"keepalive",False,"site",loc,False);
1987 st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
1989 dict_read_bool(dict,"local-mobile",False,"site",loc,False);
1991 /* Sanity check (which also allows the 'sites' file to include
1992 site() closures for all sites including our own): refuse to
1993 talk to ourselves */
1994 if (strcmp(st->localname,st->remotename)==0) {
1995 Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
1997 if (st->peer_mobile != st->local_mobile)
1998 cfgfatal(loc,"site","site %s's peer-mobile=%d"
1999 " but our local-mobile=%d\n",
2000 st->localname, st->peer_mobile, st->local_mobile);
2004 if (st->peer_mobile && st->local_mobile) {
2005 Message(M_WARNING,"site %s: site is mobile but so are we"
2006 " -> ignoring this site\n", st->remotename);
2011 assert(index_sequence < 0xffffffffUL);
2012 st->index = ++index_sequence;
2013 st->local_capabilities = 0;
2014 st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
2016 #define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
2017 list_t *things##_cfg=dict_lookup(dict,dictkey); \
2018 if (!things##_cfg) \
2019 cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
2020 st->nthings=list_length(things##_cfg); \
2021 NEW_ARY(st->things,st->nthings); \
2022 assert(st->nthings); \
2023 for (i=0; i<st->nthings; i++) { \
2024 item_t *item=list_elem(things##_cfg,i); \
2025 if (item->type!=t_closure) \
2026 cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
2027 closure_t *cl=item->data.closure; \
2028 if (cl->type!=CL_TYPE) \
2029 cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
2030 st->things[i]=cl->interface; \
2034 GET_CLOSURE_LIST("comm",comms,ncomms,CL_COMM);
2036 st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
2037 st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
2038 st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
2040 st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
2041 st->addresses=dict_read_string_array(dict,"address",False,"site",loc,0);
2043 st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
2044 else st->remoteport=0;
2045 st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc);
2047 GET_CLOSURE_LIST("transform",transforms,ntransforms,CL_TRANSFORM);
2049 st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
2050 st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
2052 #define DEFAULT(D) (st->peer_mobile || st->local_mobile \
2053 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
2054 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
2056 st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
2057 st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
2058 st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
2059 st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME);
2060 st->mtu_target= dict_read_number(dict,"mtu-target",False,"site",loc,0);
2062 st->mobile_peer_expiry= dict_read_number(
2063 dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
2065 const char *peerskey= st->peer_mobile
2066 ? "mobile-peers-max" : "static-peers-max";
2067 st->transport_peers_max= dict_read_number(
2068 dict,peerskey,False,"site",loc, st->addresses ? 4 : 3);
2069 if (st->transport_peers_max<1 ||
2070 st->transport_peers_max>MAX_PEER_ADDRS) {
2071 cfgfatal(loc,"site", "%s must be in range 1.."
2072 STRING(MAX_PEER_ADDRS) "\n", peerskey);
2075 if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
2076 st->key_renegotiate_time=st->key_lifetime/2;
2078 st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
2079 st->key_renegotiate_time=dict_read_number(
2080 dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
2081 if (st->key_renegotiate_time > st->key_lifetime) {
2082 cfgfatal(loc,"site",
2083 "renegotiate-time must be less than key-lifetime\n");
2086 st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
2087 log_event_table,"site");
2089 st->resolving_count=0;
2090 st->allow_send_prod=0;
2092 st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
2094 sprintf(st->tunname,"%s<->%s",st->localname,st->remotename);
2096 /* The information we expect to see in incoming messages of type 1 */
2097 /* fixme: lots of unchecked overflows here, but the results are only
2098 corrupted packets rather than undefined behaviour */
2099 st->setup_priority=(strcmp(st->localname,st->remotename)>0);
2101 buffer_new(&st->buffer,SETUP_BUFFER_LEN);
2103 buffer_new(&st->scratch,SETUP_BUFFER_LEN);
2104 BUF_ALLOC(&st->scratch,"site:scratch");
2106 /* We are interested in poll(), but only for timeouts. We don't have
2107 any fds of our own. */
2108 register_for_poll(st, site_beforepoll, site_afterpoll, "site");
2111 st->remote_capabilities=0;
2112 st->chosen_transform=0;
2113 st->current.key_timeout=0;
2114 st->auxiliary_key.key_timeout=0;
2115 transport_peers_clear(st,&st->peers);
2116 transport_peers_clear(st,&st->setup_peers);
2117 /* XXX mlock these */
2118 st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
2119 st->sharedsecretlen=st->sharedsecretallocd=0;
2122 for (i=0; i<st->ntransforms; i++) {
2123 struct transform_if *ti=st->transforms[i];
2124 uint32_t capbit = 1UL << ti->capab_transformnum;
2125 if (st->local_capabilities & capbit)
2126 slog(st,LOG_ERROR,"transformnum capability bit"
2127 " %d (%#"PRIx32") reused", ti->capab_transformnum, capbit);
2128 st->local_capabilities |= capbit;
2131 /* We need to register the remote networks with the netlink device */
2132 uint32_t netlink_mtu; /* local virtual interface mtu */
2133 st->netlink->reg(st->netlink->st, site_outgoing, st, &netlink_mtu);
2134 if (!st->mtu_target)
2135 st->mtu_target=netlink_mtu;
2137 for (i=0; i<st->ncomms; i++)
2138 st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
2140 st->current.transform=0;
2141 st->auxiliary_key.transform=0;
2142 st->new_transform=0;
2143 st->auxiliary_is_new=0;
2145 enter_state_stop(st);
2147 add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
2148 add_hook(PHASE_CHILDPERSIST,site_childpersist_clearkeys,st);
2150 return new_closure(&st->cl);
2153 void site_module(dict_t *dict)
2155 add_closure(dict,"site",site_apply);
2159 /***** TRANSPORT PEERS definitions *****/
2161 static void transport_peers_debug(struct site *st, transport_peers *dst,
2162 const char *didwhat,
2163 int nargs, const struct comm_addr *args,
2168 if (!(st->log_events & LOG_PEER_ADDRS))
2169 return; /* an optimisation */
2171 slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
2172 (dst==&st->peers ? "data" :
2173 dst==&st->setup_peers ? "setup" : "UNKNOWN"),
2174 didwhat, nargs, dst->npeers);
2176 for (i=0, argp=(void*)args;
2178 i++, (argp+=stride?stride:sizeof(*args))) {
2179 const struct comm_addr *ca=(void*)argp;
2180 slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
2181 i, comm_addr_to_string(ca));
2183 for (i=0; i<dst->npeers; i++) {
2184 struct timeval diff;
2185 timersub(tv_now,&dst->peers[i].last,&diff);
2186 const struct comm_addr *ca=&dst->peers[i].addr;
2187 slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
2188 i, comm_addr_to_string(ca),
2189 (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
2193 static void transport_peers_expire(struct site *st, transport_peers *peers) {
2194 /* peers must be sorted first */
2195 int previous_peers=peers->npeers;
2196 struct timeval oldest;
2197 oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
2198 oldest.tv_usec = tv_now->tv_usec;
2199 while (peers->npeers>1 &&
2200 timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
2202 if (peers->npeers != previous_peers)
2203 transport_peers_debug(st,peers,"expire", 0,0,0);
2206 static bool_t transport_peer_record_one(struct site *st, transport_peers *peers,
2207 const struct comm_addr *ca,
2208 const struct timeval *tv) {
2209 /* returns false if output is full */
2212 if (peers->npeers >= st->transport_peers_max)
2215 for (search=0; search<peers->npeers; search++)
2216 if (comm_addr_equal(&peers->peers[search].addr, ca))
2219 peers->peers[peers->npeers].addr = *ca;
2220 peers->peers[peers->npeers].last = *tv;
2225 static void transport_record_peers(struct site *st, transport_peers *peers,
2226 const struct comm_addr *addrs, int naddrs,
2228 /* We add addrs into peers. The new entries end up at the front
2229 * and displace entries towards the end (perhaps even off the
2230 * end). Any existing matching entries are moved up to the front.
2232 * Caller must first call transport_peers_expire. */
2234 if (naddrs==1 && peers->npeers>=1 &&
2235 comm_addr_equal(&addrs[0], &peers->peers[0].addr)) {
2236 /* optimisation, also avoids debug for trivial updates */
2237 peers->peers[0].last = *tv_now;
2241 int old_npeers=peers->npeers;
2242 transport_peer old_peers[old_npeers];
2243 COPY_ARRAY(old_peers,peers->peers,old_npeers);
2247 for (i=0; i<naddrs; i++) {
2248 if (!transport_peer_record_one(st,peers, &addrs[i], tv_now))
2251 for (i=0; i<old_npeers; i++) {
2252 const transport_peer *old=&old_peers[i];
2253 if (!transport_peer_record_one(st,peers, &old->addr, &old->last))
2257 transport_peers_debug(st,peers,m, naddrs,addrs,0);
2260 static void transport_expire_record_peers(struct site *st,
2261 transport_peers *peers,
2262 const struct comm_addr *addrs,
2263 int naddrs, const char *m) {
2264 /* Convenience function */
2265 transport_peers_expire(st,peers);
2266 transport_record_peers(st,peers,addrs,naddrs,m);
2269 static bool_t transport_compute_setupinit_peers(struct site *st,
2270 const struct comm_addr *configured_addrs /* 0 if none or not found */,
2271 int n_configured_addrs /* 0 if none or not found */,
2272 const struct comm_addr *incoming_packet_addr /* 0 if none */) {
2273 if (!n_configured_addrs && !incoming_packet_addr &&
2274 !transport_peers_valid(&st->peers))
2277 slog(st,LOG_SETUP_INIT,
2278 "using: %d configured addr(s);%s %d old peer addrs(es)",
2280 incoming_packet_addr ? " incoming packet address;" : "",
2283 /* Non-mobile peers try addresses until one is plausible. The
2284 * effect is that this code always tries first the configured
2285 * address if supplied, or otherwise the address of the incoming
2286 * PROD, or finally the existing data peer if one exists; this is
2289 transport_peers_copy(st,&st->setup_peers,&st->peers);
2290 transport_peers_expire(st,&st->setup_peers);
2292 if (incoming_packet_addr)
2293 transport_record_peers(st,&st->setup_peers,
2294 incoming_packet_addr,1, "incoming");
2296 if (n_configured_addrs)
2297 transport_record_peers(st,&st->setup_peers,
2298 configured_addrs,n_configured_addrs, "setupinit");
2300 assert(transport_peers_valid(&st->setup_peers));
2304 static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
2305 if (st->peer_mobile)
2306 transport_expire_record_peers(st,&st->setup_peers,a,1,"setupmsg");
2308 static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
2309 if (st->peer_mobile)
2310 transport_expire_record_peers(st,&st->peers,a,1,"datamsg");
2313 static int transport_peers_valid(transport_peers *peers) {
2314 return peers->npeers;
2316 static void transport_peers_clear(struct site *st, transport_peers *peers) {
2318 transport_peers_debug(st,peers,"clear",0,0,0);
2320 static void transport_peers_copy(struct site *st, transport_peers *dst,
2321 const transport_peers *src) {
2322 dst->npeers=src->npeers;
2323 COPY_ARRAY(dst->peers, src->peers, dst->npeers);
2324 transport_peers_debug(st,dst,"copy",
2325 src->npeers, &src->peers->addr, sizeof(*src->peers));
2328 static void transport_resolve_complete(struct site *st,
2329 const struct comm_addr *addrs,
2331 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2333 transport_expire_record_peers(st,&st->setup_peers,addrs,naddrs,
2337 static void transport_resolve_complete_tardy(struct site *st,
2338 const struct comm_addr *addrs,
2340 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2341 "resolved tardily");
2344 static void transport_peers__copy_by_mask(transport_peer *out, int *nout_io,
2346 const transport_peers *inp) {
2347 /* out and in->peers may be the same region, or nonoverlapping */
2348 const transport_peer *in=inp->peers;
2350 for (slot=0; slot<inp->npeers; slot++) {
2351 if (!(mask & (1U << slot)))
2353 if (!(out==in && slot==*nout_io))
2354 COPY_OBJ(out[*nout_io], in[slot]);
2359 void transport_xmit(struct site *st, transport_peers *peers,
2360 struct buffer_if *buf, bool_t candebug) {
2362 transport_peers_expire(st, peers);
2363 unsigned failed=0; /* bitmask */
2364 assert(MAX_PEER_ADDRS < sizeof(unsigned)*CHAR_BIT);
2367 for (slot=0; slot<peers->npeers; slot++) {
2368 transport_peer *peer=&peers->peers[slot];
2369 bool_t ok = comm_addr_sendmsg(st, &peer->addr, buf);
2371 dump_packet(st, buf, &peer->addr, False, ok);
2373 failed |= 1U << slot;
2376 if (ok && !st->peer_mobile)
2379 /* Now we need to demote/delete failing addrs: if we are mobile we
2380 * merely demote them; otherwise we delete them. */
2381 if (st->local_mobile) {
2382 unsigned expected = ((1U << nfailed)-1) << (peers->npeers-nfailed);
2383 /* `expected' has all the failures at the end already */
2384 if (failed != expected) {
2386 transport_peer failedpeers[nfailed];
2387 transport_peers__copy_by_mask(failedpeers, &fslot, failed,peers);
2388 assert(fslot == nfailed);
2390 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2391 assert(wslot+nfailed == peers->npeers);
2392 COPY_ARRAY(peers->peers+wslot, failedpeers, nfailed);
2393 transport_peers_debug(st,peers,"mobile failure reorder",0,0,0);
2396 if (failed && peers->npeers > 1) {
2398 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2399 peers->npeers=wslot;
2400 transport_peers_debug(st,peers,"non-mobile failure cleanup",0,0,0);
2405 /***** END of transport peers declarations *****/