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 3 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;
308 struct comm_clientinfo **commclientinfos;
310 struct resolver_if *resolver;
312 struct random_if *random;
313 struct rsaprivkey_if *privkey;
314 struct rsapubkey_if *pubkey;
315 struct transform_if **transforms;
318 struct hash_if *hash;
320 uint32_t index; /* Index of this site */
321 uint32_t local_capabilities;
322 int32_t setup_retries; /* How many times to send setup packets */
323 int32_t setup_retry_interval; /* Initial timeout for setup packets */
324 int32_t wait_timeout; /* How long to wait if setup unsuccessful */
325 int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
326 int32_t key_lifetime; /* How long a key lasts once set up */
327 int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
328 after this time, initiate a new
331 bool_t setup_priority; /* Do we have precedence if both sites emit
332 message 1 simultaneously? */
335 /* runtime information */
337 uint64_t now; /* Most recently seen time */
338 bool_t allow_send_prod;
339 bool_t msg1_crossed_logged;
341 int resolving_n_results_all;
342 int resolving_n_results_stored;
343 struct comm_addr resolving_results[MAX_PEER_ADDRS];
345 /* The currently established session */
346 struct data_key current;
347 struct data_key auxiliary_key;
348 bool_t auxiliary_is_new;
349 uint64_t renegotiate_key_time; /* When we can negotiate a new key */
350 uint64_t auxiliary_renegotiate_key_time;
351 transport_peers peers; /* Current address(es) of peer for data traffic */
353 /* The current key setup protocol exchange. We can only be
354 involved in one of these at a time. There's a potential for
355 denial of service here (the attacker keeps sending a setup
356 packet; we keep trying to continue the exchange, and have to
357 timeout before we can listen for another setup packet); perhaps
358 we should keep a list of 'bad' sources for setup packets. */
359 uint32_t remote_capabilities;
360 uint16_t remote_adv_mtu;
361 struct transform_if *chosen_transform;
362 uint32_t setup_session_id;
363 transport_peers setup_peers;
364 uint8_t localN[NONCELEN]; /* Nonces for key exchange */
365 uint8_t remoteN[NONCELEN];
366 struct buffer_if buffer; /* Current outgoing key exchange packet */
367 struct buffer_if scratch;
368 int32_t retries; /* Number of retries remaining */
369 uint64_t timeout; /* Timeout for current state */
371 uint8_t *sharedsecret;
372 uint32_t sharedsecretlen, sharedsecretallocd;
373 struct transform_inst_if *new_transform; /* For key setup/verify */
376 static uint32_t event_log_priority(struct site *st, uint32_t event)
378 if (!(event&st->log_events))
381 case LOG_UNEXPECTED: return M_INFO;
382 case LOG_SETUP_INIT: return M_INFO;
383 case LOG_SETUP_TIMEOUT: return M_NOTICE;
384 case LOG_ACTIVATE_KEY: return M_INFO;
385 case LOG_TIMEOUT_KEY: return M_INFO;
386 case LOG_SEC: return M_SECURITY;
387 case LOG_STATE: return M_DEBUG;
388 case LOG_DROP: return M_DEBUG;
389 case LOG_DUMP: return M_DEBUG;
390 case LOG_ERROR: return M_ERR;
391 case LOG_PEER_ADDRS: return M_DEBUG;
392 default: return M_ERR;
396 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
398 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
402 class=event_log_priority(st, event);
404 slilog_part(st->log,class,"%s: ",st->tunname);
405 vslilog_part(st->log,class,msg,ap);
406 slilog_part(st->log,class,"\n");
410 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
412 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
416 vslog(st,event,msg,ap);
420 static void logtimeout(struct site *st, const char *fmt, ...)
422 static void logtimeout(struct site *st, const char *fmt, ...)
424 uint32_t class=event_log_priority(st,LOG_SETUP_TIMEOUT);
431 slilog_part(st->log,class,"%s: ",st->tunname);
432 vslilog_part(st->log,class,fmt,ap);
436 for (i=0, delim=" (tried ";
437 i<st->setup_peers.npeers;
439 transport_peer *peer=&st->setup_peers.peers[i];
440 const char *s=comm_addr_to_string(&peer->addr);
441 slilog_part(st->log,class,"%s%s",delim,s);
444 slilog_part(st->log,class,")\n");
448 static void set_link_quality(struct site *st);
449 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
450 static void delete_one_key(struct site *st, struct data_key *key,
451 const char *reason /* may be 0 meaning don't log*/,
452 const char *which /* ignored if !reasonn */,
453 uint32_t loglevel /* ignored if !reasonn */);
454 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
455 const struct comm_addr *prod_hint);
456 static void enter_state_run(struct site *st);
457 static bool_t enter_state_resolve(struct site *st);
458 static void decrement_resolving_count(struct site *st, int by);
459 static bool_t enter_new_state(struct site *st,uint32_t next);
460 static void enter_state_wait(struct site *st);
461 static void activate_new_key(struct site *st);
463 static bool_t is_transform_valid(struct transform_inst_if *transform)
465 return transform && transform->valid(transform->st);
468 static bool_t current_valid(struct site *st)
470 return is_transform_valid(st->current.transform);
473 #define DEFINE_CALL_TRANSFORM(fwdrev) \
474 static int call_transform_##fwdrev(struct site *st, \
475 struct transform_inst_if *transform, \
476 struct buffer_if *buf, \
477 const char **errmsg) \
479 if (!is_transform_valid(transform)) { \
480 *errmsg="transform not set up"; \
483 return transform->fwdrev(transform->st,buf,errmsg); \
486 DEFINE_CALL_TRANSFORM(forwards)
487 DEFINE_CALL_TRANSFORM(reverse)
489 static void dispose_transform(struct transform_inst_if **transform_var)
491 struct transform_inst_if *transform=*transform_var;
493 transform->delkey(transform->st);
494 transform->destroy(transform->st);
499 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
500 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
501 #define CHECK_TYPE(b,t) do { uint32_t type; \
502 CHECK_AVAIL((b),4); \
503 type=buf_unprepend_uint32((b)); \
504 if (type!=(t)) return False; } while(0)
506 static _Bool type_is_msg34(uint32_t type)
509 type == LABEL_MSG3 ||
510 type == LABEL_MSG3BIS ||
517 struct buffer_if extrainfo;
524 struct parsedname remote;
525 struct parsedname local;
526 uint32_t remote_capabilities;
528 int capab_transformnum;
538 static _Bool set_new_transform(struct site *st, char *pk)
542 /* Make room for the shared key */
543 st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
544 assert(st->sharedsecretlen);
545 if (st->sharedsecretlen > st->sharedsecretallocd) {
546 st->sharedsecretallocd=st->sharedsecretlen;
547 st->sharedsecret=safe_realloc_ary(st->sharedsecret,1,
548 st->sharedsecretallocd,
549 "site:sharedsecret");
552 /* Generate the shared key */
553 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,pk,
554 st->sharedsecret,st->sharedsecretlen);
556 /* Set up the transform */
557 struct transform_if *generator=st->chosen_transform;
558 struct transform_inst_if *generated=generator->create(generator->st);
559 ok = generated->setkey(generated->st,st->sharedsecret,
560 st->sharedsecretlen,st->setup_priority);
562 dispose_transform(&st->new_transform);
563 if (!ok) return False;
564 st->new_transform=generated;
566 slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
567 " %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
568 st->chosen_transform->capab_transformnum,
569 st->local_capabilities, st->remote_capabilities);
574 int32_t lenpos, afternul;
576 static void append_string_xinfo_start(struct buffer_if *buf,
577 struct xinfoadd *xia,
579 /* Helps construct one of the names with additional info as found
580 * in MSG1..4. Call this function first, then append all the
581 * desired extra info (not including the nul byte) to the buffer,
582 * then call append_string_xinfo_done. */
584 xia->lenpos = buf->size;
585 buf_append_string(buf,str);
586 buf_append_uint8(buf,0);
587 xia->afternul = buf->size;
589 static void append_string_xinfo_done(struct buffer_if *buf,
590 struct xinfoadd *xia)
592 /* we just need to adjust the string length */
593 if (buf->size == xia->afternul) {
594 /* no extra info, strip the nul too */
595 buf_unappend_uint8(buf);
597 put_uint16(buf->start+xia->lenpos, buf->size-(xia->lenpos+2));
601 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
602 out using a transform of config data supplied by netlink */
603 static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what)
609 st->retries=st->setup_retries;
610 BUF_ALLOC(&st->buffer,what);
611 buffer_init(&st->buffer,0);
612 buf_append_uint32(&st->buffer,
613 (type==LABEL_MSG1?0:st->setup_session_id));
614 buf_append_uint32(&st->buffer,st->index);
615 buf_append_uint32(&st->buffer,type);
618 append_string_xinfo_start(&st->buffer,&xia,st->localname);
619 if ((st->local_capabilities & CAPAB_EARLY) || (type != LABEL_MSG1)) {
620 buf_append_uint32(&st->buffer,st->local_capabilities);
622 if (type_is_msg34(type)) {
623 buf_append_uint16(&st->buffer,st->mtu_target);
625 append_string_xinfo_done(&st->buffer,&xia);
627 buf_append_string(&st->buffer,st->remotename);
628 BUF_ADD_OBJ(append,&st->buffer,st->localN);
629 if (type==LABEL_MSG1) return True;
630 BUF_ADD_OBJ(append,&st->buffer,st->remoteN);
631 if (type==LABEL_MSG2) return True;
633 if (hacky_par_mid_failnow()) return False;
635 if (type==LABEL_MSG3BIS)
636 buf_append_uint8(&st->buffer,st->chosen_transform->capab_transformnum);
638 dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
639 buf_append_string(&st->buffer,dhpub);
641 hash=safe_malloc(st->hash->len, "generate_msg");
642 hst=st->hash->init();
643 st->hash->update(hst,st->buffer.start,st->buffer.size);
644 st->hash->final(hst,hash);
645 sig=st->privkey->sign(st->privkey->st,hash,st->hash->len);
646 buf_append_string(&st->buffer,sig);
652 static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
655 nm->len=buf_unprepend_uint16(msg);
656 CHECK_AVAIL(msg,nm->len);
657 nm->name=buf_unprepend(msg,nm->len);
658 uint8_t *nul=memchr(nm->name,0,nm->len);
660 buffer_readonly_view(&nm->extrainfo,0,0);
662 buffer_readonly_view(&nm->extrainfo, nul+1, msg->start-(nul+1));
663 nm->len=nul-nm->name;
668 static bool_t unpick_msg(struct site *st, uint32_t type,
669 struct buffer_if *msg, struct msg *m)
671 m->capab_transformnum=-1;
672 m->hashstart=msg->start;
674 m->dest=buf_unprepend_uint32(msg);
676 m->source=buf_unprepend_uint32(msg);
677 CHECK_TYPE(msg,type);
678 if (!unpick_name(msg,&m->remote)) return False;
679 m->remote_capabilities=0;
681 if (m->remote.extrainfo.size) {
682 CHECK_AVAIL(&m->remote.extrainfo,4);
683 m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
685 if (type_is_msg34(type) && m->remote.extrainfo.size) {
686 CHECK_AVAIL(&m->remote.extrainfo,2);
687 m->remote_mtu=buf_unprepend_uint16(&m->remote.extrainfo);
689 if (!unpick_name(msg,&m->local)) return False;
690 if (type==LABEL_PROD) {
694 CHECK_AVAIL(msg,NONCELEN);
695 m->nR=buf_unprepend(msg,NONCELEN);
696 if (type==LABEL_MSG1) {
700 CHECK_AVAIL(msg,NONCELEN);
701 m->nL=buf_unprepend(msg,NONCELEN);
702 if (type==LABEL_MSG2) {
706 if (type==LABEL_MSG3BIS) {
708 m->capab_transformnum = buf_unprepend_uint8(msg);
710 m->capab_transformnum = CAPAB_TRANSFORMNUM_ANCIENT;
713 m->pklen=buf_unprepend_uint16(msg);
714 CHECK_AVAIL(msg,m->pklen);
715 m->pk=buf_unprepend(msg,m->pklen);
716 m->hashlen=msg->start-m->hashstart;
718 m->siglen=buf_unprepend_uint16(msg);
719 CHECK_AVAIL(msg,m->siglen);
720 m->sig=buf_unprepend(msg,m->siglen);
723 /* In `process_msg3_msg4' below, we assume that we can write a nul
724 * terminator following the signature. Make sure there's enough space.
726 if (msg->start >= msg->base + msg->alloclen)
732 static bool_t name_matches(const struct parsedname *nm, const char *expected)
734 int expected_len=strlen(expected);
736 nm->len == expected_len &&
737 !memcmp(nm->name, expected, expected_len);
740 static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
743 if (type==LABEL_MSG1) return True;
745 /* Check that the site names and our nonce have been sent
746 back correctly, and then store our peer's nonce. */
747 if (!name_matches(&m->remote,st->remotename)) {
748 *error="wrong remote site name";
751 if (!name_matches(&m->local,st->localname)) {
752 *error="wrong local site name";
755 if (memcmp(m->nL,st->localN,NONCELEN)!=0) {
756 *error="wrong locally-generated nonce";
759 if (type==LABEL_MSG2) return True;
760 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) {
761 *error="wrong remotely-generated nonce";
764 /* MSG3 has complicated rules about capabilities, which are
765 * handled in process_msg3. */
766 if (type==LABEL_MSG3 || type==LABEL_MSG3BIS) return True;
767 if (m->remote_capabilities!=st->remote_capabilities) {
768 *error="remote capabilities changed";
771 if (type==LABEL_MSG4) return True;
772 *error="unknown message type";
776 static bool_t generate_msg1(struct site *st)
778 st->random->generate(st->random->st,NONCELEN,st->localN);
779 return generate_msg(st,LABEL_MSG1,"site:MSG1");
782 static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
783 const struct comm_addr *src, struct msg *m)
785 /* We've already determined we're in an appropriate state to
786 process an incoming MSG1, and that the MSG1 has correct values
789 st->setup_session_id=m->source;
790 st->remote_capabilities=m->remote_capabilities;
791 memcpy(st->remoteN,m->nR,NONCELEN);
795 static bool_t generate_msg2(struct site *st)
797 st->random->generate(st->random->st,NONCELEN,st->localN);
798 return generate_msg(st,LABEL_MSG2,"site:MSG2");
801 static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
802 const struct comm_addr *src)
807 if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False;
808 if (!check_msg(st,LABEL_MSG2,&m,&err)) {
809 slog(st,LOG_SEC,"msg2: %s",err);
812 st->setup_session_id=m.source;
813 st->remote_capabilities=m.remote_capabilities;
815 /* Select the transform to use */
817 uint32_t remote_transforms = st->remote_capabilities & CAPAB_TRANSFORM_MASK;
818 if (!remote_transforms)
819 /* old secnets only had this one transform */
820 remote_transforms = 1UL << CAPAB_TRANSFORMNUM_ANCIENT;
822 struct transform_if *ti;
824 for (i=0; i<st->ntransforms; i++) {
825 ti=st->transforms[i];
826 if ((1UL << ti->capab_transformnum) & remote_transforms)
827 goto transform_found;
829 slog(st,LOG_ERROR,"no transforms in common"
830 " (us %#"PRIx32"; them: %#"PRIx32")",
831 st->local_capabilities & CAPAB_TRANSFORM_MASK,
835 st->chosen_transform=ti;
837 memcpy(st->remoteN,m.nR,NONCELEN);
841 static bool_t generate_msg3(struct site *st)
843 /* Now we have our nonce and their nonce. Think of a secret key,
844 and create message number 3. */
845 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
846 return generate_msg(st,
847 (st->remote_capabilities & CAPAB_TRANSFORM_MASK
848 ? LABEL_MSG3BIS : LABEL_MSG3),
852 static bool_t process_msg3_msg4(struct site *st, struct msg *m)
857 /* Check signature and store g^x mod m */
858 hash=safe_malloc(st->hash->len, "process_msg3_msg4");
859 hst=st->hash->init();
860 st->hash->update(hst,m->hashstart,m->hashlen);
861 st->hash->final(hst,hash);
862 /* Terminate signature with a '0' - already checked that this will fit */
864 if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m->sig)) {
865 slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
871 st->remote_adv_mtu=m->remote_mtu;
876 static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
877 const struct comm_addr *src, uint32_t msgtype)
882 assert(msgtype==LABEL_MSG3 || msgtype==LABEL_MSG3BIS);
884 if (!unpick_msg(st,msgtype,msg3,&m)) return False;
885 if (!check_msg(st,msgtype,&m,&err)) {
886 slog(st,LOG_SEC,"msg3: %s",err);
889 uint32_t capab_adv_late = m.remote_capabilities
890 & ~st->remote_capabilities & CAPAB_EARLY;
891 if (capab_adv_late) {
892 slog(st,LOG_SEC,"msg3 impermissibly adds early capability flag(s)"
893 " %#"PRIx32" (was %#"PRIx32", now %#"PRIx32")",
894 capab_adv_late, st->remote_capabilities, m.remote_capabilities);
897 st->remote_capabilities|=m.remote_capabilities;
899 struct transform_if *ti;
901 for (i=0; i<st->ntransforms; i++) {
902 ti=st->transforms[i];
903 if (ti->capab_transformnum == m.capab_transformnum)
904 goto transform_found;
906 slog(st,LOG_SEC,"peer chose unknown-to-us transform %d!",
907 m.capab_transformnum);
910 st->chosen_transform=ti;
912 if (!process_msg3_msg4(st,&m))
915 /* Terminate their DH public key with a '0' */
917 /* Invent our DH secret key */
918 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
920 /* Generate the shared key and set up the transform */
921 if (!set_new_transform(st,m.pk)) return False;
926 static bool_t generate_msg4(struct site *st)
928 /* We have both nonces, their public key and our private key. Generate
929 our public key, sign it and send it to them. */
930 return generate_msg(st,LABEL_MSG4,"site:MSG4");
933 static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
934 const struct comm_addr *src)
939 if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False;
940 if (!check_msg(st,LABEL_MSG4,&m,&err)) {
941 slog(st,LOG_SEC,"msg4: %s",err);
945 if (!process_msg3_msg4(st,&m))
948 /* Terminate their DH public key with a '0' */
951 /* Generate the shared key and set up the transform */
952 if (!set_new_transform(st,m.pk)) return False;
963 static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0,
967 m->dest=buf_unprepend_uint32(msg0);
969 m->source=buf_unprepend_uint32(msg0);
971 m->type=buf_unprepend_uint32(msg0);
973 /* Leaves transformed part of buffer untouched */
976 static bool_t generate_msg5(struct site *st)
978 cstring_t transform_err;
980 BUF_ALLOC(&st->buffer,"site:MSG5");
981 /* We are going to add four words to the message */
982 buffer_init(&st->buffer,calculate_max_start_pad());
983 /* Give the netlink code an opportunity to put its own stuff in the
984 message (configuration information, etc.) */
985 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
986 if (call_transform_forwards(st,st->new_transform,
987 &st->buffer,&transform_err))
989 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
990 buf_prepend_uint32(&st->buffer,st->index);
991 buf_prepend_uint32(&st->buffer,st->setup_session_id);
993 st->retries=st->setup_retries;
997 static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
998 const struct comm_addr *src,
999 struct transform_inst_if *transform)
1002 cstring_t transform_err;
1004 if (!unpick_msg0(st,msg5,&m)) return False;
1006 if (call_transform_reverse(st,transform,msg5,&transform_err)) {
1007 /* There's a problem */
1008 slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
1011 /* Buffer should now contain untransformed PING packet data */
1012 CHECK_AVAIL(msg5,4);
1013 if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) {
1014 slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
1017 /* Older versions of secnet used to write some config data here
1018 * which we ignore. So we don't CHECK_EMPTY */
1022 static void create_msg6(struct site *st, struct transform_inst_if *transform,
1023 uint32_t session_id)
1025 cstring_t transform_err;
1027 BUF_ALLOC(&st->buffer,"site:MSG6");
1028 /* We are going to add four words to the message */
1029 buffer_init(&st->buffer,calculate_max_start_pad());
1030 /* Give the netlink code an opportunity to put its own stuff in the
1031 message (configuration information, etc.) */
1032 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1033 int problem = call_transform_forwards(st,transform,
1034 &st->buffer,&transform_err);
1036 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1037 buf_prepend_uint32(&st->buffer,st->index);
1038 buf_prepend_uint32(&st->buffer,session_id);
1041 static bool_t generate_msg6(struct site *st)
1043 if (!is_transform_valid(st->new_transform))
1045 create_msg6(st,st->new_transform,st->setup_session_id);
1046 st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
1050 static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
1051 const struct comm_addr *src)
1054 cstring_t transform_err;
1056 if (!unpick_msg0(st,msg6,&m)) return False;
1058 if (call_transform_reverse(st,st->new_transform,msg6,&transform_err)) {
1059 /* There's a problem */
1060 slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
1063 /* Buffer should now contain untransformed PING packet data */
1064 CHECK_AVAIL(msg6,4);
1065 if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) {
1066 slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
1069 /* Older versions of secnet used to write some config data here
1070 * which we ignore. So we don't CHECK_EMPTY */
1074 static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0,
1075 const struct comm_addr *src)
1077 cstring_t transform_err, auxkey_err, newkey_err="n/a";
1081 if (!unpick_msg0(st,msg0,&m)) return False;
1083 /* Keep a copy so we can try decrypting it with multiple keys */
1084 buffer_copy(&st->scratch, msg0);
1086 problem = call_transform_reverse(st,st->current.transform,
1087 msg0,&transform_err);
1089 if (!st->auxiliary_is_new)
1090 delete_one_key(st,&st->auxiliary_key,
1091 "peer has used new key","auxiliary key",LOG_SEC);
1097 buffer_copy(msg0, &st->scratch);
1098 problem = call_transform_reverse(st,st->auxiliary_key.transform,
1101 slog(st,LOG_DROP,"processing packet which uses auxiliary key");
1102 if (st->auxiliary_is_new) {
1103 /* We previously timed out in state SENTMSG5 but it turns
1104 * out that our peer did in fact get our MSG5 and is
1105 * using the new key. So we should switch to it too. */
1106 /* This is a bit like activate_new_key. */
1109 st->current=st->auxiliary_key;
1110 st->auxiliary_key=t;
1112 delete_one_key(st,&st->auxiliary_key,"peer has used new key",
1113 "previous key",LOG_SEC);
1114 st->auxiliary_is_new=0;
1115 st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
1122 if (st->state==SITE_SENTMSG5) {
1123 buffer_copy(msg0, &st->scratch);
1124 problem = call_transform_reverse(st,st->new_transform,
1127 /* It looks like we didn't get the peer's MSG6 */
1128 /* This is like a cut-down enter_new_state(SITE_RUN) */
1129 slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
1130 BUF_FREE(&st->buffer);
1132 activate_new_key(st);
1133 return True; /* do process the data in this packet */
1139 slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
1140 transform_err,auxkey_err,newkey_err);
1141 initiate_key_setup(st,"incoming message would not decrypt",0);
1142 send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
1146 slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err);
1151 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
1152 const struct comm_addr *src)
1156 if (!decrypt_msg0(st,msg0,src))
1159 CHECK_AVAIL(msg0,4);
1160 type=buf_unprepend_uint32(msg0);
1163 /* We must forget about the current session. */
1164 delete_keys(st,"request from peer",LOG_SEC);
1165 /* probably, the peer is shutting down, and this is going to fail,
1166 * but we need to be trying to bring the link up again */
1168 initiate_key_setup(st,"peer requested key teardown",0);
1171 /* Deliver to netlink layer */
1172 st->netlink->deliver(st->netlink->st,msg0);
1173 transport_data_msgok(st,src);
1174 /* See whether we should start negotiating a new key */
1175 if (st->now > st->renegotiate_key_time)
1176 initiate_key_setup(st,"incoming packet in renegotiation window",0);
1179 slog(st,LOG_SEC,"incoming encrypted message of type %08x "
1186 static void dump_packet(struct site *st, struct buffer_if *buf,
1187 const struct comm_addr *addr, bool_t incoming,
1190 uint32_t dest=get_uint32(buf->start);
1191 uint32_t source=get_uint32(buf->start+4);
1192 uint32_t msgtype=get_uint32(buf->start+8);
1194 if (st->log_events & LOG_DUMP)
1195 slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x: %s%s",
1196 st->tunname,incoming?"incoming":"outgoing",
1197 dest,source,msgtype,comm_addr_to_string(addr),
1201 static bool_t comm_addr_sendmsg(struct site *st,
1202 const struct comm_addr *dest,
1203 struct buffer_if *buf)
1206 struct comm_clientinfo *commclientinfo = 0;
1208 for (i=0; i < st->ncomms; i++) {
1209 if (st->comms[i] == dest->comm) {
1210 commclientinfo = st->commclientinfos[i];
1214 return dest->comm->sendmsg(dest->comm->st, buf, dest, commclientinfo);
1217 static uint32_t site_status(void *st)
1222 static bool_t send_msg(struct site *st)
1224 if (st->retries>0) {
1225 transport_xmit(st, &st->setup_peers, &st->buffer, True);
1226 st->timeout=st->now+st->setup_retry_interval;
1229 } else if (st->state==SITE_SENTMSG5) {
1230 logtimeout(st,"timed out sending MSG5, stashing new key");
1231 /* We stash the key we have produced, in case it turns out that
1232 * our peer did see our MSG5 after all and starts using it. */
1233 /* This is a bit like some of activate_new_key */
1234 struct transform_inst_if *t;
1235 t=st->auxiliary_key.transform;
1236 st->auxiliary_key.transform=st->new_transform;
1237 st->new_transform=t;
1238 dispose_transform(&st->new_transform);
1240 st->auxiliary_is_new=1;
1241 st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
1242 st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
1243 st->auxiliary_key.remote_session_id=st->setup_session_id;
1245 enter_state_wait(st);
1248 logtimeout(st,"timed out sending key setup packet "
1249 "(in state %s)",state_name(st->state));
1250 enter_state_wait(st);
1255 static void site_resolve_callback(void *sst, const struct comm_addr *addrs,
1256 int stored_naddrs, int all_naddrs,
1257 const char *address, const char *failwhy)
1259 struct site *st=sst;
1261 if (!stored_naddrs) {
1262 slog(st,LOG_ERROR,"resolution of %s failed: %s",address,failwhy);
1264 slog(st,LOG_PEER_ADDRS,"resolution of %s completed, %d addrs, eg: %s",
1265 address, all_naddrs, comm_addr_to_string(&addrs[0]));;
1267 int space=st->transport_peers_max-st->resolving_n_results_stored;
1268 int n_tocopy=MIN(stored_naddrs,space);
1269 COPY_ARRAY(st->resolving_results + st->resolving_n_results_stored,
1272 st->resolving_n_results_stored += n_tocopy;
1273 st->resolving_n_results_all += all_naddrs;
1276 decrement_resolving_count(st,1);
1279 static void decrement_resolving_count(struct site *st, int by)
1281 assert(st->resolving_count>0);
1282 st->resolving_count-=by;
1284 if (st->resolving_count)
1287 /* OK, we are done with them all. Handle combined results. */
1289 const struct comm_addr *addrs=st->resolving_results;
1290 int naddrs=st->resolving_n_results_stored;
1291 assert(naddrs<=st->transport_peers_max);
1294 if (naddrs != st->resolving_n_results_all) {
1295 slog(st,LOG_SETUP_INIT,"resolution of supplied addresses/names"
1296 " yielded too many results (%d > %d), some ignored",
1297 st->resolving_n_results_all, naddrs);
1299 slog(st,LOG_STATE,"resolution completed, %d addrs, eg: %s",
1300 naddrs, iaddr_to_string(&addrs[0].ia));;
1303 switch (st->state) {
1305 if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) {
1306 enter_new_state(st,SITE_SENTMSG1);
1308 /* Can't figure out who to try to to talk to */
1309 slog(st,LOG_SETUP_INIT,
1310 "key exchange failed: cannot find peer address");
1311 enter_state_run(st);
1314 case SITE_SENTMSG1: case SITE_SENTMSG2:
1315 case SITE_SENTMSG3: case SITE_SENTMSG4:
1318 /* We start using the address immediately for data too.
1319 * It's best to store it in st->peers now because we might
1320 * go via SENTMSG5, WAIT, and a MSG0, straight into using
1321 * the new key (without updating the data peer addrs). */
1322 transport_resolve_complete(st,addrs,naddrs);
1323 } else if (st->local_mobile) {
1324 /* We can't let this rest because we may have a peer
1325 * address which will break in the future. */
1326 slog(st,LOG_SETUP_INIT,"resolution failed: "
1327 "abandoning key exchange");
1328 enter_state_wait(st);
1330 slog(st,LOG_SETUP_INIT,"resolution failed: "
1331 " continuing to use source address of peer's packets"
1332 " for key exchange and ultimately data");
1337 slog(st,LOG_SETUP_INIT,"resolution completed tardily,"
1338 " updating peer address(es)");
1339 transport_resolve_complete_tardy(st,addrs,naddrs);
1340 } else if (st->local_mobile) {
1341 /* Not very good. We should queue (another) renegotiation
1342 * so that we can update the peer address. */
1343 st->key_renegotiate_time=st->now+st->wait_timeout;
1345 slog(st,LOG_SETUP_INIT,"resolution failed: "
1346 " continuing to use source address of peer's packets");
1356 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
1357 const struct comm_addr *prod_hint)
1359 /* Reentrancy hazard: can call enter_new_state/enter_state_* */
1360 if (st->state!=SITE_RUN) return False;
1361 slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
1362 if (st->addresses) {
1363 slog(st,LOG_SETUP_INIT,"resolving peer address(es)");
1364 return enter_state_resolve(st);
1365 } else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) {
1366 return enter_new_state(st,SITE_SENTMSG1);
1368 slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
1372 static void activate_new_key(struct site *st)
1374 struct transform_inst_if *t;
1376 /* We have three transform instances, which we swap between old,
1378 t=st->auxiliary_key.transform;
1379 st->auxiliary_key.transform=st->current.transform;
1380 st->current.transform=st->new_transform;
1381 st->new_transform=t;
1382 dispose_transform(&st->new_transform);
1385 st->auxiliary_is_new=0;
1386 st->auxiliary_key.key_timeout=st->current.key_timeout;
1387 st->current.key_timeout=st->now+st->key_lifetime;
1388 st->renegotiate_key_time=st->now+st->key_renegotiate_time;
1389 transport_peers_copy(st,&st->peers,&st->setup_peers);
1390 st->current.remote_session_id=st->setup_session_id;
1392 /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
1393 * But their mtu be unspecified, in which case we just use ours. */
1394 uint32_t intersite_mtu=
1395 MIN(st->mtu_target, st->remote_adv_mtu ?: ~(uint32_t)0);
1396 st->netlink->set_mtu(st->netlink->st,intersite_mtu);
1398 slog(st,LOG_ACTIVATE_KEY,"new key activated"
1399 " (mtu ours=%"PRId32" theirs=%"PRId32" intersite=%"PRId32")",
1400 st->mtu_target, st->remote_adv_mtu, intersite_mtu);
1401 enter_state_run(st);
1404 static void delete_one_key(struct site *st, struct data_key *key,
1405 cstring_t reason, cstring_t which, uint32_t loglevel)
1407 if (!is_transform_valid(key->transform)) return;
1408 if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
1409 dispose_transform(&key->transform);
1413 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
1415 if (current_valid(st)) {
1416 slog(st,loglevel,"session closed (%s)",reason);
1418 delete_one_key(st,&st->current,0,0,0);
1419 set_link_quality(st);
1421 delete_one_key(st,&st->auxiliary_key,0,0,0);
1424 static void state_assert(struct site *st, bool_t ok)
1426 if (!ok) fatal("site:state_assert");
1429 static void enter_state_stop(struct site *st)
1431 st->state=SITE_STOP;
1433 delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
1434 dispose_transform(&st->new_transform);
1437 static void set_link_quality(struct site *st)
1440 if (current_valid(st))
1441 quality=LINK_QUALITY_UP;
1442 else if (st->state==SITE_WAIT || st->state==SITE_STOP)
1443 quality=LINK_QUALITY_DOWN;
1444 else if (st->addresses)
1445 quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
1446 else if (transport_peers_valid(&st->peers))
1447 quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
1449 quality=LINK_QUALITY_DOWN;
1451 st->netlink->set_quality(st->netlink->st,quality);
1454 static void enter_state_run(struct site *st)
1456 slog(st,LOG_STATE,"entering state RUN");
1460 st->setup_session_id=0;
1461 transport_peers_clear(st,&st->setup_peers);
1462 FILLZERO(st->localN);
1463 FILLZERO(st->remoteN);
1464 dispose_transform(&st->new_transform);
1465 memset(st->dhsecret,0,st->dh->len);
1466 if (st->sharedsecret) memset(st->sharedsecret,0,st->sharedsecretlen);
1467 set_link_quality(st);
1469 if (st->keepalive && !current_valid(st))
1470 initiate_key_setup(st, "keepalive", 0);
1473 static bool_t ensure_resolving(struct site *st)
1475 /* Reentrancy hazard: may call site_resolve_callback and hence
1476 * enter_new_state, enter_state_* and generate_msg*. */
1477 if (st->resolving_count)
1480 assert(st->addresses);
1482 /* resolver->request might reentrantly call site_resolve_callback
1483 * which will decrement st->resolving, so we need to increment it
1484 * twice beforehand to prevent decrement from thinking we're
1485 * finished, and decrement it ourselves. Alternatively if
1486 * everything fails then there are no callbacks due and we simply
1487 * set it to 0 and return false.. */
1488 st->resolving_n_results_stored=0;
1489 st->resolving_n_results_all=0;
1490 st->resolving_count+=2;
1491 const char **addrp=st->addresses;
1492 const char *address;
1494 for (; (address=*addrp++); ) {
1495 bool_t ok = st->resolver->request(st->resolver->st,address,
1496 st->remoteport,st->comms[0],
1497 site_resolve_callback,st);
1499 st->resolving_count++;
1503 st->resolving_count=0;
1506 decrement_resolving_count(st,2);
1510 static bool_t enter_state_resolve(struct site *st)
1512 /* Reentrancy hazard! See ensure_resolving. */
1513 state_assert(st,st->state==SITE_RUN);
1514 slog(st,LOG_STATE,"entering state RESOLVE");
1515 st->state=SITE_RESOLVE;
1516 return ensure_resolving(st);
1519 static bool_t enter_new_state(struct site *st, uint32_t next)
1521 bool_t (*gen)(struct site *st);
1524 slog(st,LOG_STATE,"entering state %s",state_name(next));
1527 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
1529 st->msg1_crossed_logged = False;
1532 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1533 st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
1537 state_assert(st,st->state==SITE_SENTMSG1);
1538 BUF_FREE(&st->buffer);
1542 state_assert(st,st->state==SITE_SENTMSG2);
1543 BUF_FREE(&st->buffer);
1547 state_assert(st,st->state==SITE_SENTMSG3);
1548 BUF_FREE(&st->buffer);
1552 state_assert(st,st->state==SITE_SENTMSG4);
1553 BUF_FREE(&st->buffer);
1558 fatal("enter_new_state(%s): invalid new state",state_name(next));
1562 if (hacky_par_start_failnow()) return False;
1564 r= gen(st) && send_msg(st);
1567 st->setup_retries, st->setup_retry_interval,
1572 if (next==SITE_RUN) {
1573 BUF_FREE(&st->buffer); /* Never reused */
1574 st->timeout=0; /* Never retransmit */
1575 activate_new_key(st);
1579 slog(st,LOG_ERROR,"error entering state %s",state_name(next));
1580 st->buffer.free=False; /* Unconditionally use the buffer; it may be
1581 in either state, and enter_state_wait() will
1583 enter_state_wait(st);
1587 /* msg7 tells our peer that we're about to forget our key */
1588 static bool_t send_msg7(struct site *st, cstring_t reason)
1590 cstring_t transform_err;
1592 if (current_valid(st) && st->buffer.free
1593 && transport_peers_valid(&st->peers)) {
1594 BUF_ALLOC(&st->buffer,"site:MSG7");
1595 buffer_init(&st->buffer,calculate_max_start_pad());
1596 buf_append_uint32(&st->buffer,LABEL_MSG7);
1597 buf_append_string(&st->buffer,reason);
1598 if (call_transform_forwards(st, st->current.transform,
1599 &st->buffer, &transform_err))
1601 buf_prepend_uint32(&st->buffer,LABEL_MSG0);
1602 buf_prepend_uint32(&st->buffer,st->index);
1603 buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
1604 transport_xmit(st,&st->peers,&st->buffer,True);
1605 BUF_FREE(&st->buffer);
1612 /* We go into this state if our peer becomes uncommunicative. Similar to
1613 the "stop" state, we forget all session keys for a while, before
1614 re-entering the "run" state. */
1615 static void enter_state_wait(struct site *st)
1617 slog(st,LOG_STATE,"entering state WAIT");
1618 st->timeout=st->now+st->wait_timeout;
1619 st->state=SITE_WAIT;
1620 set_link_quality(st);
1621 BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
1622 /* XXX Erase keys etc. */
1625 static void generate_prod(struct site *st, struct buffer_if *buf)
1628 buf_append_uint32(buf,0);
1629 buf_append_uint32(buf,0);
1630 buf_append_uint32(buf,LABEL_PROD);
1631 buf_append_string(buf,st->localname);
1632 buf_append_string(buf,st->remotename);
1635 static void generate_send_prod(struct site *st,
1636 const struct comm_addr *source)
1638 if (!st->allow_send_prod) return; /* too soon */
1639 if (!(st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1640 st->state==SITE_WAIT)) return; /* we'd ignore peer's MSG1 */
1642 slog(st,LOG_SETUP_INIT,"prodding peer for key exchange");
1643 st->allow_send_prod=0;
1644 generate_prod(st,&st->scratch);
1645 bool_t ok = comm_addr_sendmsg(st, source, &st->scratch);
1646 dump_packet(st,&st->scratch,source,False,ok);
1649 static inline void site_settimeout(uint64_t timeout, int *timeout_io)
1652 int64_t offset=timeout-*now;
1653 if (offset<0) offset=0;
1654 if (offset>INT_MAX) offset=INT_MAX;
1655 if (*timeout_io<0 || offset<*timeout_io)
1660 static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
1663 struct site *st=sst;
1665 BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
1668 /* Work out when our next timeout is. The earlier of 'timeout' or
1669 'current.key_timeout'. A stored value of '0' indicates no timeout
1671 site_settimeout(st->timeout, timeout_io);
1672 site_settimeout(st->current.key_timeout, timeout_io);
1673 site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
1675 return 0; /* success */
1678 static void check_expiry(struct site *st, struct data_key *key,
1681 if (key->key_timeout && *now>key->key_timeout) {
1682 delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
1686 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1687 static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
1689 struct site *st=sst;
1692 if (st->timeout && *now>st->timeout) {
1694 if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) {
1695 if (!hacky_par_start_failnow())
1697 } else if (st->state==SITE_WAIT) {
1698 enter_state_run(st);
1700 slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d",
1704 check_expiry(st,&st->current,"current key");
1705 check_expiry(st,&st->auxiliary_key,"auxiliary key");
1708 /* This function is called by the netlink device to deliver packets
1709 intended for the remote network. The packet is in "raw" wire
1710 format, but is guaranteed to be word-aligned. */
1711 static void site_outgoing(void *sst, struct buffer_if *buf)
1713 struct site *st=sst;
1714 cstring_t transform_err;
1716 if (st->state==SITE_STOP) {
1721 st->allow_send_prod=1;
1723 /* In all other states we consider delivering the packet if we have
1724 a valid key and a valid address to send it to. */
1725 if (current_valid(st) && transport_peers_valid(&st->peers)) {
1726 /* Transform it and send it */
1728 buf_prepend_uint32(buf,LABEL_MSG9);
1729 if (call_transform_forwards(st, st->current.transform,
1730 buf, &transform_err))
1732 buf_prepend_uint32(buf,LABEL_MSG0);
1733 buf_prepend_uint32(buf,st->index);
1734 buf_prepend_uint32(buf,st->current.remote_session_id);
1735 transport_xmit(st,&st->peers,buf,False);
1742 slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size);
1744 initiate_key_setup(st,"outgoing packet",0);
1747 static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
1748 uint32_t type, struct msg *m)
1749 /* For packets which are identified by the local and remote names.
1750 * If it has our name and our peer's name in it it's for us. */
1752 struct buffer_if buf[1];
1753 buffer_readonly_clone(buf,buf_in);
1754 return unpick_msg(st,type,buf,m)
1755 && name_matches(&m->remote,st->remotename)
1756 && name_matches(&m->local,st->localname);
1759 /* This function is called by the communication device to deliver
1760 packets from our peers.
1761 It should return True if the packet is recognised as being for
1762 this current site instance (and should therefore not be processed
1763 by other sites), even if the packet was otherwise ignored. */
1764 static bool_t site_incoming(void *sst, struct buffer_if *buf,
1765 const struct comm_addr *source)
1767 struct site *st=sst;
1769 if (buf->size < 12) return False;
1771 uint32_t dest=get_uint32(buf->start);
1772 uint32_t msgtype=get_uint32(buf->start+8);
1773 struct msg named_msg;
1775 if (msgtype==LABEL_MSG1) {
1776 if (!named_for_us(st,buf,msgtype,&named_msg))
1778 /* It's a MSG1 addressed to us. Decide what to do about it. */
1779 dump_packet(st,buf,source,True,True);
1780 if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1781 st->state==SITE_WAIT) {
1782 /* We should definitely process it */
1783 transport_compute_setupinit_peers(st,0,0,source);
1784 if (process_msg1(st,buf,source,&named_msg)) {
1785 slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
1786 bool_t entered=enter_new_state(st,SITE_SENTMSG2);
1787 if (entered && st->addresses && st->local_mobile)
1788 /* We must do this as the very last thing, because
1789 the resolver callback might reenter us. */
1790 ensure_resolving(st);
1792 slog(st,LOG_ERROR,"failed to process incoming msg1");
1796 } else if (st->state==SITE_SENTMSG1) {
1797 /* We've just sent a message 1! They may have crossed on
1798 the wire. If we have priority then we ignore the
1799 incoming one, otherwise we process it as usual. */
1800 if (st->setup_priority) {
1802 if (!st->msg1_crossed_logged++)
1803 slog(st,LOG_DUMP,"crossed msg1s; we are higher "
1804 "priority => ignore incoming msg1");
1807 slog(st,LOG_DUMP,"crossed msg1s; we are lower "
1808 "priority => use incoming msg1");
1809 if (process_msg1(st,buf,source,&named_msg)) {
1810 BUF_FREE(&st->buffer); /* Free our old message 1 */
1811 transport_setup_msgok(st,source);
1812 enter_new_state(st,SITE_SENTMSG2);
1814 slog(st,LOG_ERROR,"failed to process an incoming "
1815 "crossed msg1 (we have low priority)");
1821 /* The message 1 was received at an unexpected stage of the
1822 key setup. XXX POLICY - what do we do? */
1823 slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
1827 if (msgtype==LABEL_PROD) {
1828 if (!named_for_us(st,buf,msgtype,&named_msg))
1830 dump_packet(st,buf,source,True,True);
1831 if (st->state!=SITE_RUN) {
1832 slog(st,LOG_DROP,"ignoring PROD when not in state RUN");
1833 } else if (current_valid(st)) {
1834 slog(st,LOG_DROP,"ignoring PROD when we think we have a key");
1836 initiate_key_setup(st,"peer sent PROD packet",source);
1841 if (dest==st->index) {
1842 /* Explicitly addressed to us */
1843 if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True,True);
1846 /* If the source is our current peer then initiate a key setup,
1847 because our peer's forgotten the key */
1848 if (get_uint32(buf->start+4)==st->current.remote_session_id) {
1850 initiated = initiate_key_setup(st,"received a NAK",source);
1851 if (!initiated) generate_send_prod(st,source);
1853 slog(st,LOG_SEC,"bad incoming NAK");
1857 process_msg0(st,buf,source);
1860 /* Setup packet: should not have been explicitly addressed
1862 slog(st,LOG_SEC,"incoming explicitly addressed msg1");
1865 /* Setup packet: expected only in state SENTMSG1 */
1866 if (st->state!=SITE_SENTMSG1) {
1867 slog(st,LOG_UNEXPECTED,"unexpected MSG2");
1868 } else if (process_msg2(st,buf,source)) {
1869 transport_setup_msgok(st,source);
1870 enter_new_state(st,SITE_SENTMSG3);
1872 slog(st,LOG_SEC,"invalid MSG2");
1877 /* Setup packet: expected only in state SENTMSG2 */
1878 if (st->state!=SITE_SENTMSG2) {
1879 slog(st,LOG_UNEXPECTED,"unexpected MSG3");
1880 } else if (process_msg3(st,buf,source,msgtype)) {
1881 transport_setup_msgok(st,source);
1882 enter_new_state(st,SITE_SENTMSG4);
1884 slog(st,LOG_SEC,"invalid MSG3");
1888 /* Setup packet: expected only in state SENTMSG3 */
1889 if (st->state!=SITE_SENTMSG3) {
1890 slog(st,LOG_UNEXPECTED,"unexpected MSG4");
1891 } else if (process_msg4(st,buf,source)) {
1892 transport_setup_msgok(st,source);
1893 enter_new_state(st,SITE_SENTMSG5);
1895 slog(st,LOG_SEC,"invalid MSG4");
1899 /* Setup packet: expected only in state SENTMSG4 */
1900 /* (may turn up in state RUN if our return MSG6 was lost
1901 and the new key has already been activated. In that
1902 case we discard it. The peer will realise that we
1903 are using the new key when they see our data packets.
1904 Until then the peer's data packets to us get discarded. */
1905 if (st->state==SITE_SENTMSG4) {
1906 if (process_msg5(st,buf,source,st->new_transform)) {
1907 transport_setup_msgok(st,source);
1908 enter_new_state(st,SITE_RUN);
1910 slog(st,LOG_SEC,"invalid MSG5");
1912 } else if (st->state==SITE_RUN) {
1913 if (process_msg5(st,buf,source,st->current.transform)) {
1914 slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
1915 transport_setup_msgok(st,source);
1916 create_msg6(st,st->current.transform,
1917 st->current.remote_session_id);
1918 transport_xmit(st,&st->peers,&st->buffer,True);
1919 BUF_FREE(&st->buffer);
1921 slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
1924 slog(st,LOG_UNEXPECTED,"unexpected MSG5");
1928 /* Setup packet: expected only in state SENTMSG5 */
1929 if (st->state!=SITE_SENTMSG5) {
1930 slog(st,LOG_UNEXPECTED,"unexpected MSG6");
1931 } else if (process_msg6(st,buf,source)) {
1932 BUF_FREE(&st->buffer); /* Free message 5 */
1933 transport_setup_msgok(st,source);
1934 activate_new_key(st);
1936 slog(st,LOG_SEC,"invalid MSG6");
1940 slog(st,LOG_SEC,"received message of unknown type 0x%08x",
1951 static void site_control(void *vst, bool_t run)
1953 struct site *st=vst;
1954 if (run) enter_state_run(st);
1955 else enter_state_stop(st);
1958 static void site_phase_hook(void *sst, uint32_t newphase)
1960 struct site *st=sst;
1962 /* The program is shutting down; tell our peer */
1963 send_msg7(st,"shutting down");
1966 static void site_childpersist_clearkeys(void *sst, uint32_t newphase)
1968 struct site *st=sst;
1969 dispose_transform(&st->current.transform);
1970 dispose_transform(&st->auxiliary_key.transform);
1971 dispose_transform(&st->new_transform);
1972 /* Not much point overwiting the signing key, since we loaded it
1973 from disk, and it is only valid prospectively if at all,
1975 /* XXX it would be best to overwrite the DH state, because that
1976 _is_ relevant to forward secrecy. However we have no
1977 convenient interface for doing that and in practice gmp has
1978 probably dribbled droppings all over the malloc arena. A good
1979 way to fix this would be to have a privsep child for asymmetric
1980 crypto operations, but that's a task for another day. */
1983 static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
1986 static uint32_t index_sequence;
1994 st->cl.description="site";
1995 st->cl.type=CL_SITE;
1997 st->cl.interface=&st->ops;
1999 st->ops.control=site_control;
2000 st->ops.status=site_status;
2002 /* First parameter must be a dict */
2003 item=list_elem(args,0);
2004 if (!item || item->type!=t_dict)
2005 cfgfatal(loc,"site","parameter must be a dictionary\n");
2007 dict=item->data.dict;
2008 st->localname=dict_read_string(dict, "local-name", True, "site", loc);
2009 st->remotename=dict_read_string(dict, "name", True, "site", loc);
2011 st->keepalive=dict_read_bool(dict,"keepalive",False,"site",loc,False);
2013 st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
2015 dict_read_bool(dict,"local-mobile",False,"site",loc,False);
2017 /* Sanity check (which also allows the 'sites' file to include
2018 site() closures for all sites including our own): refuse to
2019 talk to ourselves */
2020 if (strcmp(st->localname,st->remotename)==0) {
2021 Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
2023 if (st->peer_mobile != st->local_mobile)
2024 cfgfatal(loc,"site","site %s's peer-mobile=%d"
2025 " but our local-mobile=%d\n",
2026 st->localname, st->peer_mobile, st->local_mobile);
2030 if (st->peer_mobile && st->local_mobile) {
2031 Message(M_WARNING,"site %s: site is mobile but so are we"
2032 " -> ignoring this site\n", st->remotename);
2037 assert(index_sequence < 0xffffffffUL);
2038 st->index = ++index_sequence;
2039 st->local_capabilities = 0;
2040 st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
2042 #define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
2043 list_t *things##_cfg=dict_lookup(dict,dictkey); \
2044 if (!things##_cfg) \
2045 cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
2046 st->nthings=list_length(things##_cfg); \
2047 NEW_ARY(st->things,st->nthings); \
2048 assert(st->nthings); \
2049 for (i=0; i<st->nthings; i++) { \
2050 item_t *item=list_elem(things##_cfg,i); \
2051 if (item->type!=t_closure) \
2052 cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
2053 closure_t *cl=item->data.closure; \
2054 if (cl->type!=CL_TYPE) \
2055 cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
2056 st->things[i]=cl->interface; \
2060 GET_CLOSURE_LIST("comm",comms,ncomms,CL_COMM);
2062 NEW_ARY(st->commclientinfos, st->ncomms);
2063 dict_t *comminfo = dict_read_dict(dict,"comm-info",False,"site",loc);
2064 for (i=0; i<st->ncomms; i++) {
2065 st->commclientinfos[i] =
2067 st->comms[i]->clientinfo(st->comms[i],comminfo,loc);
2070 st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
2071 st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
2072 st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
2074 st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc);
2075 st->addresses=dict_read_string_array(dict,"address",False,"site",loc,0);
2077 st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
2078 else st->remoteport=0;
2079 st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc);
2081 GET_CLOSURE_LIST("transform",transforms,ntransforms,CL_TRANSFORM);
2083 st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
2084 st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
2086 #define DEFAULT(D) (st->peer_mobile || st->local_mobile \
2087 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
2088 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
2090 st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
2091 st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
2092 st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
2093 st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME);
2094 st->mtu_target= dict_read_number(dict,"mtu-target",False,"site",loc,0);
2096 st->mobile_peer_expiry= dict_read_number(
2097 dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
2099 const char *peerskey= st->peer_mobile
2100 ? "mobile-peers-max" : "static-peers-max";
2101 st->transport_peers_max= dict_read_number(
2102 dict,peerskey,False,"site",loc, st->addresses ? 4 : 3);
2103 if (st->transport_peers_max<1 ||
2104 st->transport_peers_max>MAX_PEER_ADDRS) {
2105 cfgfatal(loc,"site", "%s must be in range 1.."
2106 STRING(MAX_PEER_ADDRS) "\n", peerskey);
2109 if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
2110 st->key_renegotiate_time=st->key_lifetime/2;
2112 st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
2113 st->key_renegotiate_time=dict_read_number(
2114 dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
2115 if (st->key_renegotiate_time > st->key_lifetime) {
2116 cfgfatal(loc,"site",
2117 "renegotiate-time must be less than key-lifetime\n");
2120 st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
2121 log_event_table,"site");
2123 st->resolving_count=0;
2124 st->allow_send_prod=0;
2126 st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
2128 sprintf(st->tunname,"%s<->%s",st->localname,st->remotename);
2130 /* The information we expect to see in incoming messages of type 1 */
2131 /* fixme: lots of unchecked overflows here, but the results are only
2132 corrupted packets rather than undefined behaviour */
2133 st->setup_priority=(strcmp(st->localname,st->remotename)>0);
2135 buffer_new(&st->buffer,SETUP_BUFFER_LEN);
2137 buffer_new(&st->scratch,SETUP_BUFFER_LEN);
2138 BUF_ALLOC(&st->scratch,"site:scratch");
2140 /* We are interested in poll(), but only for timeouts. We don't have
2141 any fds of our own. */
2142 register_for_poll(st, site_beforepoll, site_afterpoll, "site");
2145 st->remote_capabilities=0;
2146 st->chosen_transform=0;
2147 st->current.key_timeout=0;
2148 st->auxiliary_key.key_timeout=0;
2149 transport_peers_clear(st,&st->peers);
2150 transport_peers_clear(st,&st->setup_peers);
2151 /* XXX mlock these */
2152 st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
2153 st->sharedsecretlen=st->sharedsecretallocd=0;
2156 for (i=0; i<st->ntransforms; i++) {
2157 struct transform_if *ti=st->transforms[i];
2158 uint32_t capbit = 1UL << ti->capab_transformnum;
2159 if (st->local_capabilities & capbit)
2160 slog(st,LOG_ERROR,"transformnum capability bit"
2161 " %d (%#"PRIx32") reused", ti->capab_transformnum, capbit);
2162 st->local_capabilities |= capbit;
2165 /* We need to register the remote networks with the netlink device */
2166 uint32_t netlink_mtu; /* local virtual interface mtu */
2167 st->netlink->reg(st->netlink->st, site_outgoing, st, &netlink_mtu);
2168 if (!st->mtu_target)
2169 st->mtu_target=netlink_mtu;
2171 for (i=0; i<st->ncomms; i++)
2172 st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
2174 st->current.transform=0;
2175 st->auxiliary_key.transform=0;
2176 st->new_transform=0;
2177 st->auxiliary_is_new=0;
2179 enter_state_stop(st);
2181 add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
2182 add_hook(PHASE_CHILDPERSIST,site_childpersist_clearkeys,st);
2184 return new_closure(&st->cl);
2187 void site_module(dict_t *dict)
2189 add_closure(dict,"site",site_apply);
2193 /***** TRANSPORT PEERS definitions *****/
2195 static void transport_peers_debug(struct site *st, transport_peers *dst,
2196 const char *didwhat,
2197 int nargs, const struct comm_addr *args,
2202 if (!(st->log_events & LOG_PEER_ADDRS))
2203 return; /* an optimisation */
2205 slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
2206 (dst==&st->peers ? "data" :
2207 dst==&st->setup_peers ? "setup" : "UNKNOWN"),
2208 didwhat, nargs, dst->npeers);
2210 for (i=0, argp=(void*)args;
2212 i++, (argp+=stride?stride:sizeof(*args))) {
2213 const struct comm_addr *ca=(void*)argp;
2214 slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
2215 i, comm_addr_to_string(ca));
2217 for (i=0; i<dst->npeers; i++) {
2218 struct timeval diff;
2219 timersub(tv_now,&dst->peers[i].last,&diff);
2220 const struct comm_addr *ca=&dst->peers[i].addr;
2221 slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
2222 i, comm_addr_to_string(ca),
2223 (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
2227 static void transport_peers_expire(struct site *st, transport_peers *peers) {
2228 /* peers must be sorted first */
2229 int previous_peers=peers->npeers;
2230 struct timeval oldest;
2231 oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
2232 oldest.tv_usec = tv_now->tv_usec;
2233 while (peers->npeers>1 &&
2234 timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
2236 if (peers->npeers != previous_peers)
2237 transport_peers_debug(st,peers,"expire", 0,0,0);
2240 static bool_t transport_peer_record_one(struct site *st, transport_peers *peers,
2241 const struct comm_addr *ca,
2242 const struct timeval *tv) {
2243 /* returns false if output is full */
2246 if (peers->npeers >= st->transport_peers_max)
2249 for (search=0; search<peers->npeers; search++)
2250 if (comm_addr_equal(&peers->peers[search].addr, ca))
2253 peers->peers[peers->npeers].addr = *ca;
2254 peers->peers[peers->npeers].last = *tv;
2259 static void transport_record_peers(struct site *st, transport_peers *peers,
2260 const struct comm_addr *addrs, int naddrs,
2262 /* We add addrs into peers. The new entries end up at the front
2263 * and displace entries towards the end (perhaps even off the
2264 * end). Any existing matching entries are moved up to the front.
2266 * Caller must first call transport_peers_expire. */
2269 /* avoids debug for uninteresting updates */
2271 for (i=0; i<peers->npeers; i++) {
2272 if (comm_addr_equal(&addrs[0], &peers->peers[i].addr)) {
2273 memmove(peers->peers+1, peers->peers,
2274 sizeof(peers->peers[0]) * i);
2275 peers->peers[0].addr = addrs[0];
2276 peers->peers[0].last = *tv_now;
2282 int old_npeers=peers->npeers;
2283 transport_peer old_peers[old_npeers];
2284 COPY_ARRAY(old_peers,peers->peers,old_npeers);
2288 for (i=0; i<naddrs; i++) {
2289 if (!transport_peer_record_one(st,peers, &addrs[i], tv_now))
2292 for (i=0; i<old_npeers; i++) {
2293 const transport_peer *old=&old_peers[i];
2294 if (!transport_peer_record_one(st,peers, &old->addr, &old->last))
2298 transport_peers_debug(st,peers,m, naddrs,addrs,0);
2301 static void transport_expire_record_peers(struct site *st,
2302 transport_peers *peers,
2303 const struct comm_addr *addrs,
2304 int naddrs, const char *m) {
2305 /* Convenience function */
2306 transport_peers_expire(st,peers);
2307 transport_record_peers(st,peers,addrs,naddrs,m);
2310 static bool_t transport_compute_setupinit_peers(struct site *st,
2311 const struct comm_addr *configured_addrs /* 0 if none or not found */,
2312 int n_configured_addrs /* 0 if none or not found */,
2313 const struct comm_addr *incoming_packet_addr /* 0 if none */) {
2314 if (!n_configured_addrs && !incoming_packet_addr &&
2315 !transport_peers_valid(&st->peers))
2318 slog(st,LOG_SETUP_INIT,
2319 "using: %d configured addr(s);%s %d old peer addrs(es)",
2321 incoming_packet_addr ? " incoming packet address;" : "",
2324 /* Non-mobile peers try addresses until one is plausible. The
2325 * effect is that this code always tries first the configured
2326 * address if supplied, or otherwise the address of the incoming
2327 * PROD, or finally the existing data peer if one exists; this is
2330 transport_peers_copy(st,&st->setup_peers,&st->peers);
2331 transport_peers_expire(st,&st->setup_peers);
2333 if (incoming_packet_addr)
2334 transport_record_peers(st,&st->setup_peers,
2335 incoming_packet_addr,1, "incoming");
2337 if (n_configured_addrs)
2338 transport_record_peers(st,&st->setup_peers,
2339 configured_addrs,n_configured_addrs, "setupinit");
2341 assert(transport_peers_valid(&st->setup_peers));
2345 static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
2346 if (st->peer_mobile)
2347 transport_expire_record_peers(st,&st->setup_peers,a,1,"setupmsg");
2349 static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
2350 if (st->peer_mobile)
2351 transport_expire_record_peers(st,&st->peers,a,1,"datamsg");
2354 static int transport_peers_valid(transport_peers *peers) {
2355 return peers->npeers;
2357 static void transport_peers_clear(struct site *st, transport_peers *peers) {
2359 transport_peers_debug(st,peers,"clear",0,0,0);
2361 static void transport_peers_copy(struct site *st, transport_peers *dst,
2362 const transport_peers *src) {
2363 dst->npeers=src->npeers;
2364 COPY_ARRAY(dst->peers, src->peers, dst->npeers);
2365 transport_peers_debug(st,dst,"copy",
2366 src->npeers, &src->peers->addr, sizeof(*src->peers));
2369 static void transport_resolve_complete(struct site *st,
2370 const struct comm_addr *addrs,
2372 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2374 transport_expire_record_peers(st,&st->setup_peers,addrs,naddrs,
2378 static void transport_resolve_complete_tardy(struct site *st,
2379 const struct comm_addr *addrs,
2381 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2382 "resolved tardily");
2385 static void transport_peers__copy_by_mask(transport_peer *out, int *nout_io,
2387 const transport_peers *inp) {
2388 /* out and in->peers may be the same region, or nonoverlapping */
2389 const transport_peer *in=inp->peers;
2391 for (slot=0; slot<inp->npeers; slot++) {
2392 if (!(mask & (1U << slot)))
2394 if (!(out==in && slot==*nout_io))
2395 COPY_OBJ(out[*nout_io], in[slot]);
2400 void transport_xmit(struct site *st, transport_peers *peers,
2401 struct buffer_if *buf, bool_t candebug) {
2403 transport_peers_expire(st, peers);
2404 unsigned failed=0; /* bitmask */
2405 assert(MAX_PEER_ADDRS < sizeof(unsigned)*CHAR_BIT);
2408 for (slot=0; slot<peers->npeers; slot++) {
2409 transport_peer *peer=&peers->peers[slot];
2410 bool_t ok = comm_addr_sendmsg(st, &peer->addr, buf);
2412 dump_packet(st, buf, &peer->addr, False, ok);
2414 failed |= 1U << slot;
2417 if (ok && !st->peer_mobile)
2420 /* Now we need to demote/delete failing addrs: if we are mobile we
2421 * merely demote them; otherwise we delete them. */
2422 if (st->local_mobile) {
2423 unsigned expected = ((1U << nfailed)-1) << (peers->npeers-nfailed);
2424 /* `expected' has all the failures at the end already */
2425 if (failed != expected) {
2427 transport_peer failedpeers[nfailed];
2428 transport_peers__copy_by_mask(failedpeers, &fslot, failed,peers);
2429 assert(fslot == nfailed);
2431 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2432 assert(wslot+nfailed == peers->npeers);
2433 COPY_ARRAY(peers->peers+wslot, failedpeers, nfailed);
2434 transport_peers_debug(st,peers,"mobile failure reorder",0,0,0);
2437 if (failed && peers->npeers > 1) {
2439 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2440 peers->npeers=wslot;
2441 transport_peers_debug(st,peers,"non-mobile failure cleanup",0,0,0);
2446 /***** END of transport peers declarations *****/