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"
48 #define SETUP_BUFFER_LEN 2048
50 #define DEFAULT_KEY_LIFETIME (3600*1000) /* [ms] */
51 #define DEFAULT_KEY_RENEGOTIATE_GAP (5*60*1000) /* [ms] */
52 #define DEFAULT_SETUP_RETRIES 5
53 #define DEFAULT_SETUP_RETRY_INTERVAL (2*1000) /* [ms] */
54 #define DEFAULT_WAIT_TIME (20*1000) /* [ms] */
56 #define DEFAULT_MOBILE_KEY_LIFETIME (2*24*3600*1000) /* [ms] */
57 #define DEFAULT_MOBILE_KEY_RENEGOTIATE_GAP (12*3600*1000) /* [ms] */
58 #define DEFAULT_MOBILE_SETUP_RETRIES 30
59 #define DEFAULT_MOBILE_SETUP_RETRY_INTERVAL (1*1000) /* [ms] */
60 #define DEFAULT_MOBILE_WAIT_TIME (10*1000) /* [ms] */
62 #define DEFAULT_MOBILE_PEER_EXPIRY (2*60) /* [s] */
64 #define PEERKEYS_SUFFIX_MAXLEN (sizeof("~incoming")-1)
66 /* Each site can be in one of several possible states. */
69 SITE_STOP - nothing is allowed to happen; tunnel is down;
70 all session keys have been erased
71 -> SITE_RUN upon external instruction
72 SITE_RUN - site up, maybe with valid key
73 -> SITE_RESOLVE upon outgoing packet and no valid key
74 we start name resolution for the other end of the tunnel
75 -> SITE_SENTMSG2 upon valid incoming message 1 and suitable time
76 we send an appropriate message 2
77 SITE_RESOLVE - waiting for name resolution
78 -> SITE_SENTMSG1 upon successful resolution
79 we send an appropriate message 1
80 -> SITE_SENTMSG2 upon valid incoming message 1 (then abort resolution)
81 we abort resolution and
82 -> SITE_WAIT on timeout or resolution failure
84 -> SITE_SENTMSG2 upon valid incoming message 1 from higher priority end
85 -> SITE_SENTMSG3 upon valid incoming message 2
86 -> SITE_WAIT on timeout
88 -> SITE_SENTMSG4 upon valid incoming message 3
89 -> SITE_WAIT on timeout
91 -> SITE_SENTMSG5 upon valid incoming message 4
92 -> SITE_WAIT on timeout
94 -> SITE_RUN upon valid incoming message 5
95 -> SITE_WAIT on timeout
97 -> SITE_RUN upon valid incoming message 6
98 -> SITE_WAIT on timeout
99 SITE_WAIT - failed to establish key; do nothing for a while
100 -> SITE_RUN on timeout
105 #define SITE_RESOLVE 2
106 #define SITE_SENTMSG1 3
107 #define SITE_SENTMSG2 4
108 #define SITE_SENTMSG3 5
109 #define SITE_SENTMSG4 6
110 #define SITE_SENTMSG5 7
113 #define CASES_MSG3_KNOWN LABEL_MSG3: case LABEL_MSG3BIS
117 int32_t site_max_start_pad = 4*4;
119 static cstring_t state_name(uint32_t state)
122 case 0: return "STOP";
123 case 1: return "RUN";
124 case 2: return "RESOLVE";
125 case 3: return "SENTMSG1";
126 case 4: return "SENTMSG2";
127 case 5: return "SENTMSG3";
128 case 6: return "SENTMSG4";
129 case 7: return "SENTMSG5";
130 case 8: return "WAIT";
131 default: return "*bad state*";
137 #define LOG_UNEXPECTED 0x00000001
138 #define LOG_SETUP_INIT 0x00000002
139 #define LOG_SETUP_TIMEOUT 0x00000004
140 #define LOG_ACTIVATE_KEY 0x00000008
141 #define LOG_TIMEOUT_KEY 0x00000010
142 #define LOG_SEC 0x00000020
143 #define LOG_STATE 0x00000040
144 #define LOG_DROP 0x00000080
145 #define LOG_DUMP 0x00000100
146 #define LOG_ERROR 0x00000400
147 #define LOG_PEER_ADDRS 0x00000800
148 #define LOG_SIGKEYS 0x00001000
150 static struct flagstr log_event_table[]={
151 { "unexpected", LOG_UNEXPECTED },
152 { "setup-init", LOG_SETUP_INIT },
153 { "setup-timeout", LOG_SETUP_TIMEOUT },
154 { "activate-key", LOG_ACTIVATE_KEY },
155 { "timeout-key", LOG_TIMEOUT_KEY },
156 { "security", LOG_SEC },
157 { "state-change", LOG_STATE },
158 { "packet-drop", LOG_DROP },
159 { "dump-packets", LOG_DUMP },
160 { "errors", LOG_ERROR },
161 { "peer-addrs", LOG_PEER_ADDRS },
162 { "sigkeys", LOG_SIGKEYS },
163 { "default", LOG_SETUP_INIT|LOG_SETUP_TIMEOUT|
164 LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR|LOG_SIGKEYS },
165 { "all", 0xffffffff },
170 /***** TRANSPORT PEERS declarations *****/
172 /* Details of "mobile peer" semantics:
174 - We use the same data structure for the different configurations,
175 but manage it with different algorithms.
177 - We record up to mobile_peers_max peer address/port numbers
178 ("peers") for key setup, and separately up to mobile_peers_max
181 - In general, we make a new set of addrs (see below) when we start
182 a new key exchange; the key setup addrs become the data transport
183 addrs when key setup complets.
185 If our peer is mobile:
187 - We send to all recent addresses of incoming packets, plus
188 initially all configured addresses (which we also expire).
190 - So, we record addrs of good incoming packets, as follows:
191 1. expire any peers last seen >120s ("mobile-peer-expiry") ago
192 2. add the peer of the just received packet to the applicable list
193 (possibly evicting the oldest entries to make room)
194 NB that we do not expire peers until an incoming packet arrives.
196 - If the peer has a configured address or name, we record them the
197 same way, but only as a result of our own initiation of key
198 setup. (We might evict some incoming packet addrs to make room.)
200 - The default number of addrs to keep is 3, or 4 if we have a
201 configured name or address. That's space for two configured
202 addresses (one IPv6 and one IPv4), plus two received addresses.
204 - Outgoing packets are sent to every recorded address in the
205 applicable list. Any unsupported[1] addresses are deleted from
206 the list right away. (This should only happen to configured
207 addresses, of course, but there is no need to check that.)
209 - When we successfully complete a key setup, we merge the key setup
210 peers into the data transfer peers.
212 [1] An unsupported address is one for whose AF we don't have a
213 socket (perhaps because we got EAFNOSUPPORT or some such) or for
214 which sendto gives ENETUNREACH.
216 If neither end is mobile:
218 - When peer initiated the key exchange, we use the incoming packet
221 - When we initiate the key exchange, we try configured addresses
222 until we get one which isn't unsupported then fixate on that.
224 - When we complete a key setup, we replace the data transport peers
225 with those from the key setup.
229 - We can't tell when local network setup changes so we can't cache
230 the unsupported addrs and completely remove the spurious calls to
231 sendto, but we can optimise things a bit by deprioritising addrs
232 which seem to be unsupported.
234 - Use only configured addresses. (Except, that if our peer
235 initiated a key exchange we use the incoming packet address until
236 our name resolution completes.)
238 - When we send a packet, try each address in turn; if addr
239 supported, put that address to the end of the list for future
240 packets, and go onto the next address.
242 - When we complete a key setup, we replace the data transport peers
243 with those from the key setup.
249 struct comm_addr addr;
253 /* configuration information */
254 /* runtime information */
256 transport_peer peers[MAX_PEER_ADDRS];
259 /* Basic operations on transport peer address sets */
260 static void transport_peers_clear(struct site *st, transport_peers *peers);
261 static int transport_peers_valid(transport_peers *peers);
262 static void transport_peers_copy(struct site *st, transport_peers *dst,
263 const transport_peers *src);
265 /* Record address of incoming setup packet; resp. data packet. */
266 static void transport_setup_msgok(struct site *st, const struct comm_addr *a);
267 static void transport_data_msgok(struct site *st, const struct comm_addr *a);
269 /* Initialise the setup addresses. Called before we send the first
270 * packet in a key exchange. If we are the initiator, as a result of
271 * resolve completing (or being determined not to be relevant) or an
272 * incoming PROD; if we are the responder, as a result of the MSG1. */
273 static bool_t transport_compute_setupinit_peers(struct site *st,
274 const struct comm_addr *configured_addrs /* 0 if none or not found */,
275 int n_configured_addrs /* 0 if none or not found */,
276 const struct comm_addr *incoming_packet_addr /* 0 if none */);
278 /* Called if we are the responder in a key setup, when the resolve
279 * completes. transport_compute_setupinit_peers will hvae been called
280 * earlier. If _complete is called, we are still doing the key setup
281 * (and we should use the new values for both the rest of the key
282 * setup and the ongoing data exchange); if _tardy is called, the key
283 * setup is done (either completed or not) and only the data peers are
285 static void transport_resolve_complete(struct site *st,
286 const struct comm_addr *addrs, int naddrs);
287 static void transport_resolve_complete_tardy(struct site *st,
288 const struct comm_addr *addrs, int naddrs);
290 static void transport_xmit(struct site *st, transport_peers *peers,
291 struct buffer_if *buf, bool_t candebug);
293 /***** END of transport peers declarations *****/
297 struct transform_inst_if *transform;
298 uint64_t key_timeout; /* End of life of current key */
299 uint32_t remote_session_id;
305 /* configuration information */
309 bool_t local_mobile, peer_mobile; /* Mobile client support */
310 int32_t transport_peers_max;
311 string_t tunname; /* localname<->remotename by default, used in logs */
312 cstring_t *addresses; /* DNS name or address(es) for bootstrapping, optional */
313 int remoteport; /* Port for bootstrapping, optional */
315 struct netlink_if *netlink;
316 struct comm_if **comms;
317 struct comm_clientinfo **commclientinfos;
319 struct resolver_if *resolver;
321 struct random_if *random;
322 struct privcache_if *privkeys;
323 struct sigprivkey_if *privkey_fixed;
324 struct transform_if **transforms;
328 uint32_t index; /* Index of this site */
329 uint32_t early_capabilities;
330 uint32_t local_capabilities;
331 int32_t setup_retries; /* How many times to send setup packets */
332 int32_t setup_retry_interval; /* Initial timeout for setup packets */
333 int32_t wait_timeout_mean; /* How long to wait if setup unsuccessful */
334 int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */
335 int32_t key_lifetime; /* How long a key lasts once set up */
336 int32_t key_renegotiate_time; /* If we see traffic (or a keepalive)
337 after this time, initiate a new
340 bool_t our_name_later; /* our name > peer name */
343 /* runtime information */
345 uint64_t now; /* Most recently seen time */
346 bool_t allow_send_prod;
347 bool_t msg1_crossed_logged;
349 int resolving_n_results_all;
350 int resolving_n_results_stored;
351 struct comm_addr resolving_results[MAX_PEER_ADDRS];
352 const char *peerkeys_path;
353 struct pathprefix_template peerkeys_tmpl;
354 struct peer_keyset *peerkeys_current, *peerkeys_kex;
356 /* The currently established session */
357 struct data_key current;
358 struct data_key auxiliary_key;
359 bool_t auxiliary_is_new;
360 uint64_t renegotiate_key_time; /* When we can negotiate a new key */
361 uint64_t auxiliary_renegotiate_key_time;
362 transport_peers peers; /* Current address(es) of peer for data traffic */
364 /* The current key setup protocol exchange. We can only be
365 involved in one of these at a time. There's a potential for
366 denial of service here (the attacker keeps sending a setup
367 packet; we keep trying to continue the exchange, and have to
368 timeout before we can listen for another setup packet); perhaps
369 we should keep a list of 'bad' sources for setup packets. */
370 uint32_t remote_capabilities;
371 uint16_t remote_adv_mtu;
372 struct transform_if *chosen_transform;
373 uint32_t setup_session_id;
374 transport_peers setup_peers;
375 uint8_t localN[NONCELEN]; /* Nonces for key exchange */
376 uint8_t remoteN[NONCELEN];
377 struct buffer_if buffer; /* Current outgoing key exchange packet */
378 struct buffer_if scratch;
379 int32_t retries; /* Number of retries remaining */
380 uint64_t timeout; /* Timeout for current state */
382 uint8_t *sharedsecret;
383 uint32_t sharedsecretlen, sharedsecretallocd;
384 struct transform_inst_if *new_transform; /* For key setup/verify */
387 static uint32_t event_log_priority(struct site *st, uint32_t event)
389 if (!(event&st->log_events))
392 case LOG_UNEXPECTED: return M_INFO;
393 case LOG_SETUP_INIT: return M_INFO;
394 case LOG_SETUP_TIMEOUT: return M_NOTICE;
395 case LOG_ACTIVATE_KEY: return M_INFO;
396 case LOG_TIMEOUT_KEY: return M_INFO;
397 case LOG_SEC: return M_SECURITY;
398 case LOG_STATE: return M_DEBUG;
399 case LOG_DROP: return M_DEBUG;
400 case LOG_DUMP: return M_DEBUG;
401 case LOG_ERROR: return M_ERR;
402 case LOG_PEER_ADDRS: return M_DEBUG;
403 case LOG_SIGKEYS: return M_INFO;
404 default: return M_ERR;
408 static uint32_t slog_start(struct site *st, uint32_t event)
410 uint32_t class=event_log_priority(st, event);
412 slilog_part(st->log,class,"%s: ",st->tunname);
417 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
419 static void vslog(struct site *st, uint32_t event, cstring_t msg, va_list ap)
423 class=slog_start(st,event);
425 vslilog_part(st->log,class,msg,ap);
426 slilog_part(st->log,class,"\n");
430 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
432 static void slog(struct site *st, uint32_t event, cstring_t msg, ...)
436 vslog(st,event,msg,ap);
440 static void logtimeout(struct site *st, const char *fmt, ...)
442 static void logtimeout(struct site *st, const char *fmt, ...)
444 uint32_t class=event_log_priority(st,LOG_SETUP_TIMEOUT);
451 slilog_part(st->log,class,"%s: ",st->tunname);
452 vslilog_part(st->log,class,fmt,ap);
456 for (i=0, delim=" (tried ";
457 i<st->setup_peers.npeers;
459 transport_peer *peer=&st->setup_peers.peers[i];
460 const char *s=comm_addr_to_string(&peer->addr);
461 slilog_part(st->log,class,"%s%s",delim,s);
464 slilog_part(st->log,class,")\n");
468 static void set_link_quality(struct site *st);
469 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel);
470 static void delete_one_key(struct site *st, struct data_key *key,
471 const char *reason /* may be 0 meaning don't log*/,
472 const char *which /* ignored if !reasonn */,
473 uint32_t loglevel /* ignored if !reasonn */);
474 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
475 const struct comm_addr *prod_hint);
476 static void enter_state_run(struct site *st);
477 static bool_t enter_state_resolve(struct site *st);
478 static void decrement_resolving_count(struct site *st, int by);
479 static bool_t enter_new_state(struct site *st,uint32_t next,
480 const struct msg *prompt
481 /* may be 0 for SENTMSG1 */);
482 static void enter_state_wait(struct site *st);
483 static void activate_new_key(struct site *st);
485 static bool_t is_transform_valid(struct transform_inst_if *transform)
487 return transform && transform->valid(transform->st);
490 static bool_t current_valid(struct site *st)
492 return is_transform_valid(st->current.transform);
495 #define DEFINE_CALL_TRANSFORM(fwdrev) \
496 static transform_apply_return \
497 call_transform_##fwdrev(struct site *st, \
498 struct transform_inst_if *transform, \
499 struct buffer_if *buf, \
500 const char **errmsg) \
502 if (!is_transform_valid(transform)) { \
503 *errmsg="transform not set up"; \
504 return transform_apply_err; \
506 return transform->fwdrev(transform->st,buf,errmsg); \
509 DEFINE_CALL_TRANSFORM(forwards)
510 DEFINE_CALL_TRANSFORM(reverse)
512 static void dispose_transform(struct transform_inst_if **transform_var)
514 struct transform_inst_if *transform=*transform_var;
516 transform->delkey(transform->st);
517 transform->destroy(transform->st);
522 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
523 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
524 #define CHECK_TYPE(b,t) do { uint32_t type; \
525 CHECK_AVAIL((b),4); \
526 type=buf_unprepend_uint32((b)); \
527 if (type!=(t)) return False; } while(0)
529 static _Bool type_is_msg23(uint32_t type)
532 case LABEL_MSG2: case CASES_MSG3_KNOWN: return True;
533 default: return False;
536 static _Bool type_is_msg34(uint32_t type)
539 case CASES_MSG3_KNOWN: case LABEL_MSG4: return True;
540 default: return False;
547 struct buffer_if extrainfo;
554 struct parsedname remote;
555 struct parsedname local;
556 uint32_t remote_capabilities;
558 int capab_transformnum;
564 struct alg_msg_data sig;
565 int n_pubkeys_accepted_nom; /* may be > MAX_SIG_KEYS ! */
566 const struct sigkeyid *pubkeys_accepted[MAX_SIG_KEYS];
567 int signing_key_index;
570 static const struct sigkeyid keyid_zero;
572 static int32_t wait_timeout(struct site *st) {
573 int32_t t = st->wait_timeout_mean;
576 st->random->generate(st->random->st,sizeof(factor),&factor);
577 t += (t / 256) * factor;
582 static _Bool set_new_transform(struct site *st, char *pk)
586 /* Make room for the shared key */
587 st->sharedsecretlen=st->chosen_transform->keylen?:st->dh->ceil_len;
588 assert(st->sharedsecretlen);
589 if (st->sharedsecretlen > st->sharedsecretallocd) {
590 st->sharedsecretallocd=st->sharedsecretlen;
591 st->sharedsecret=safe_realloc_ary(st->sharedsecret,1,
592 st->sharedsecretallocd,
593 "site:sharedsecret");
596 /* Generate the shared key */
597 st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,pk,
598 st->sharedsecret,st->sharedsecretlen);
600 /* Set up the transform */
601 struct transform_if *generator=st->chosen_transform;
602 struct transform_inst_if *generated=generator->create(generator->st);
603 ok = generated->setkey(generated->st,st->sharedsecret,
604 st->sharedsecretlen,st->our_name_later);
606 dispose_transform(&st->new_transform);
607 if (!ok) return False;
608 st->new_transform=generated;
610 slog(st,LOG_SETUP_INIT,"key exchange negotiated transform"
611 " %d (capabilities ours=%#"PRIx32" theirs=%#"PRIx32")",
612 st->chosen_transform->capab_bit,
613 st->local_capabilities, st->remote_capabilities);
618 int32_t lenpos, afternul;
620 static void append_string_xinfo_start(struct buffer_if *buf,
621 struct xinfoadd *xia,
623 /* Helps construct one of the names with additional info as found
624 * in MSG1..4. Call this function first, then append all the
625 * desired extra info (not including the nul byte) to the buffer,
626 * then call append_string_xinfo_done. */
628 xia->lenpos = buf->size;
629 buf_append_string(buf,str);
630 buf_append_uint8(buf,0);
631 xia->afternul = buf->size;
633 static void append_string_xinfo_done(struct buffer_if *buf,
634 struct xinfoadd *xia)
636 /* we just need to adjust the string length */
637 if (buf->size == xia->afternul) {
638 /* no extra info, strip the nul too */
639 buf_unappend_uint8(buf);
641 put_uint16(buf->start+xia->lenpos, buf->size-(xia->lenpos+2));
645 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
646 out using a transform of config data supplied by netlink */
647 static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what,
648 const struct msg *prompt
649 /* may be 0 for MSG1 */)
655 st->retries=st->setup_retries;
656 BUF_ALLOC(&st->buffer,what);
657 buffer_init(&st->buffer,0);
658 buf_append_uint32(&st->buffer,
659 (type==LABEL_MSG1?0:st->setup_session_id));
660 buf_append_uint32(&st->buffer,st->index);
661 buf_append_uint32(&st->buffer,type);
664 append_string_xinfo_start(&st->buffer,&xia,st->localname);
665 if ((st->local_capabilities & st->early_capabilities) ||
666 (type != LABEL_MSG1)) {
667 buf_append_uint32(&st->buffer,st->local_capabilities);
669 if (type_is_msg34(type)) {
670 buf_append_uint16(&st->buffer,st->mtu_target);
672 if (type_is_msg23(type)) {
673 buf_append_uint8(&st->buffer,st->peerkeys_kex->nkeys);
674 for (ki=0; ki<st->peerkeys_kex->nkeys; ki++) {
675 struct peer_pubkey *pk = &st->peerkeys_kex->keys[ki];
676 BUF_ADD_OBJ(append,&st->buffer,pk->id);
679 struct sigprivkey_if *privkey=0;
680 if (type_is_msg34(type)) {
681 assert(prompt->n_pubkeys_accepted_nom>0);
683 ki<prompt->n_pubkeys_accepted_nom && ki<MAX_SIG_KEYS;
685 const struct sigkeyid *kid=prompt->pubkeys_accepted[ki];
687 privkey=st->privkeys->lookup(st->privkeys->st,kid,st->log);
688 if (privkey) goto privkey_found;
690 if (sigkeyid_equal(&keyid_zero,kid)) {
691 privkey=st->privkey_fixed;
696 uint32_t class = slog_start(st,LOG_ERROR);
698 slilog_part(st->log,class,"no suitable private key, peer wanted");
700 ki<prompt->n_pubkeys_accepted_nom && ki<MAX_SIG_KEYS;
702 slilog_part(st->log,class, " " SIGKEYID_PR_FMT,
703 SIGKEYID_PR_VAL(prompt->pubkeys_accepted[ki]));
705 if (prompt->n_pubkeys_accepted_nom > MAX_SIG_KEYS)
706 slilog_part(st->log,class," +%d",
707 prompt->n_pubkeys_accepted_nom - MAX_SIG_KEYS);
708 slilog_part(st->log,class,"\n");
713 buf_append_uint8(&st->buffer,ki);
716 append_string_xinfo_done(&st->buffer,&xia);
718 buf_append_string(&st->buffer,st->remotename);
719 BUF_ADD_OBJ(append,&st->buffer,st->localN);
720 if (type==LABEL_MSG1) return True;
721 BUF_ADD_OBJ(append,&st->buffer,st->remoteN);
722 if (type==LABEL_MSG2) return True;
724 if (hacky_par_mid_failnow()) return False;
726 if (MSGMAJOR(type) == 3) do {
727 minor = MSGMINOR(type);
728 if (minor < 1) break;
729 buf_append_uint8(&st->buffer,st->chosen_transform->capab_bit);
732 dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len);
733 buf_append_string(&st->buffer,dhpub);
736 bool_t ok=privkey->sign(privkey->st,
747 static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm)
750 nm->len=buf_unprepend_uint16(msg);
751 CHECK_AVAIL(msg,nm->len);
752 nm->name=buf_unprepend(msg,nm->len);
753 uint8_t *nul=memchr(nm->name,0,nm->len);
755 buffer_readonly_view(&nm->extrainfo,0,0);
757 buffer_readonly_view(&nm->extrainfo, nul+1, msg->start-(nul+1));
758 nm->len=nul-nm->name;
763 static bool_t unpick_msg(struct site *st, uint32_t type,
764 struct buffer_if *msg, struct msg *m)
768 m->n_pubkeys_accepted_nom=-1;
769 m->capab_transformnum=-1;
770 m->signing_key_index=-1;
771 m->hashstart=msg->start;
773 m->dest=buf_unprepend_uint32(msg);
775 m->source=buf_unprepend_uint32(msg);
776 CHECK_TYPE(msg,type);
777 if (!unpick_name(msg,&m->remote)) return False;
778 m->remote_capabilities=0;
780 if (m->remote.extrainfo.size) {
781 CHECK_AVAIL(&m->remote.extrainfo,4);
782 m->remote_capabilities=buf_unprepend_uint32(&m->remote.extrainfo);
784 if (type_is_msg34(type) && m->remote.extrainfo.size) {
785 CHECK_AVAIL(&m->remote.extrainfo,2);
786 m->remote_mtu=buf_unprepend_uint16(&m->remote.extrainfo);
788 if (type_is_msg23(type) && m->remote.extrainfo.size) {
789 m->n_pubkeys_accepted_nom = buf_unprepend_uint8(&m->remote.extrainfo);
790 if (!m->n_pubkeys_accepted_nom) return False;
791 for (int ki_nom=0; ki_nom<m->n_pubkeys_accepted_nom; ki_nom++) {
792 CHECK_AVAIL(&m->remote.extrainfo,KEYIDSZ);
793 struct sigkeyid *kid = buf_unprepend(&m->remote.extrainfo,KEYIDSZ);
794 if (ki_nom<MAX_SIG_KEYS) m->pubkeys_accepted[ki_nom] = kid;
797 m->n_pubkeys_accepted_nom = 1;
798 m->pubkeys_accepted[0] = &keyid_zero;
800 if (type_is_msg34(type) && m->remote.extrainfo.size) {
801 m->signing_key_index=buf_unprepend_uint8(&m->remote.extrainfo);
803 m->signing_key_index=0;
805 if (!unpick_name(msg,&m->local)) return False;
806 if (type==LABEL_PROD) {
810 CHECK_AVAIL(msg,NONCELEN);
811 m->nR=buf_unprepend(msg,NONCELEN);
812 if (type==LABEL_MSG1) {
816 CHECK_AVAIL(msg,NONCELEN);
817 m->nL=buf_unprepend(msg,NONCELEN);
818 if (type==LABEL_MSG2) {
822 if (MSGMAJOR(type) == 3) do {
823 minor = MSGMINOR(type);
824 #define MAYBE_READ_CAP(minminor, kind, dflt) do { \
825 if (minor < (minminor)) \
826 m->capab_##kind##num = (dflt); \
828 CHECK_AVAIL(msg, 1); \
829 m->capab_##kind##num = buf_unprepend_uint8(msg); \
832 MAYBE_READ_CAP(1, transform, CAPAB_BIT_ANCIENTTRANSFORM);
833 #undef MAYBE_READ_CAP
836 m->pklen=buf_unprepend_uint16(msg);
837 CHECK_AVAIL(msg,m->pklen);
838 m->pk=buf_unprepend(msg,m->pklen);
839 m->hashlen=msg->start-m->hashstart;
841 if (m->signing_key_index < 0 ||
842 m->signing_key_index >= st->peerkeys_kex->nkeys) {
845 struct sigpubkey_if *pubkey=
846 st->peerkeys_kex->keys[m->signing_key_index].pubkey;
847 if (!pubkey->unpick(pubkey->st,msg,&m->sig)) {
856 static bool_t name_matches(const struct parsedname *nm, const char *expected)
858 int expected_len=strlen(expected);
860 nm->len == expected_len &&
861 !memcmp(nm->name, expected, expected_len);
864 static bool_t check_msg(struct site *st, uint32_t type, struct msg *m,
867 if (type==LABEL_MSG1) return True;
869 /* Check that the site names and our nonce have been sent
870 back correctly, and then store our peer's nonce. */
871 if (!name_matches(&m->remote,st->remotename)) {
872 *error="wrong remote site name";
875 if (!name_matches(&m->local,st->localname)) {
876 *error="wrong local site name";
879 if (memcmp(m->nL,st->localN,NONCELEN)!=0) {
880 *error="wrong locally-generated nonce";
883 if (type==LABEL_MSG2) return True;
884 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)) {
885 *error="wrong remotely-generated nonce";
888 /* MSG3 has complicated rules about capabilities, which are
889 * handled in process_msg3. */
890 if (MSGMAJOR(type) == 3) return True;
891 if (m->remote_capabilities!=st->remote_capabilities) {
892 *error="remote capabilities changed";
895 if (type==LABEL_MSG4) return True;
896 *error="unknown message type";
900 static void peerkeys_maybe_incorporate(struct site *st, const char *file,
901 const char *whatmore,
904 struct peer_keyset *atsuffix=
905 keyset_load(file,&st->scratch,st->log,logcl_enoent);
906 if (!atsuffix) return;
908 if (st->peerkeys_current &&
909 serial_cmp(atsuffix->serial,st->peerkeys_current->serial) <= 0) {
910 slog(st,LOG_SIGKEYS,"keys from %s%s are older, discarding",
912 keyset_dispose(&atsuffix);
914 if (r) slog(st,LOG_ERROR,"failed to remove old key update %s: %s\n",
915 st->peerkeys_tmpl.buffer,strerror(errno));
918 slog(st,LOG_SIGKEYS,"keys from %s%s are newer, installing",
920 keyset_dispose(&st->peerkeys_current);
921 st->peerkeys_current=atsuffix;
922 int r=rename(file,st->peerkeys_path);
923 if (r) slog(st,LOG_ERROR,"failed to install key update %s as %s: %s\n",
924 st->peerkeys_tmpl.buffer,st->peerkeys_path,
929 static void peerkeys_check_for_update(struct site *st)
933 * <F> live file, loaded on startup, updated by secnet
934 * (only). * in-memory peerkeys_current is kept
935 * synced with this file
937 * <F>~update update file from config manager, checked before
938 * every key exchange. config manager must rename
939 * this file into place; it will be renamed and
940 * then removed by secnet.
942 * <F>~proc update file being processed by secnet.
943 * only secnet may write or remove.
945 * <F>~incoming update file from peer, being received by secnet
946 * may be incomplete, unverified, or even malicious
947 * only secnet may write or remove.
949 * secnet discards updates that are not more recent than (by
950 * serial) the live file. But it may not process updates
953 * The implied keyset to be used is MAX(live, proc, update).
956 * check live vs proc, either mv proc live or rm proc
957 * if proc doesn't exist, mv update proc
959 * make-secnet-sites does:
960 * write: rename something onto update
961 * read: read update,proc,live in that order and take max
963 * We support only one concurrent secnet, one concurrent
964 * writing make-secnet-sites, and any number of readers.
965 * We want to maintain a live file at all times as that
966 * is what secnet actually reads at startup and uses.
968 * Proof that this is sound:
969 * Let us regard update,proc,live as i=0,1,2
970 * Files contain public key sets and are manipulated as
971 * a whole, and we may regard key sets with the same
972 * serial as equivalent.
973 * We talk below about reading as if it were atomic.
974 * Actually the atomic operation is open(2); the
975 * reading gets whatever that name refers to. So
976 * we can model this as an atomic read.
977 * secnet eventually moves all data into the live file
978 * or deletes it, so there should be no indefinitely
979 * stale data; informally this means we can disregard
980 * the possibility of very old serials and regard
981 * serials as fully ordered. (We don't bother with
982 * a formal proof of this property.)
983 * Consequently we will only think about the serial
984 * and not the contents. We treat absent files as
985 * minimal (we will write -1 for convenience although
986 * we don't mean a numerical value). We write S(i).
988 * Invariant 1 for secnet's transformations is as follows:
989 * Each file S(i) is only reduced (to S'(i)) if for some j S'(j)
990 * >= S(i), with S'(j) either being >= S(i) beforehand, or
991 * updated atomically together with S(i).
993 * Proof of invariant 1 for the secnet operations:
994 * (a) check live vs proc, proc>live, mv:
995 * j=2, i=1; S'(i)=-1, so S(i) is being reduced. S'(j) is
996 * equal to S(i), and the rename is atomic [1], so S'(j) and
997 * S'(i) are updated simultaneously. S(j) is being
998 * increased. (There are no hazards from concurrent writers;
999 * only we ourselves (secnet) write to live or proc.)
1000 * (b) check live vs proc, proc<=live, rm:
1001 * j=2, i=1; S'(i)=-1, so S(i) is being reduced. But
1002 * S(j) is >= $(i) throughout. (Again, no concurrent
1004 * (c) mv update proc (when proc does not exist):
1005 * j=1, i=0; S(i) is being reduced to -1. But simultaneously
1006 * S(j) is being increased to the old S(i). Our precondition
1007 * (proc not existing) is not subject to a concurrent writer
1008 * hazards because only we write to proc; our action is
1009 * atomic and takes whatever update is available (if any).
1011 * Proof of soundness for the mss reading operation:
1012 * Let M be MAX(\forall S) at the point where mss reads update.
1013 * Invariant 2: when mss reads S(k), MAX(K, S(k)..S(2)) >= M,
1014 * where K is the max S it has seen so far. Clearly this is
1015 * true for k=0 (with K==-1). secnet's operations never break
1016 * this invariant because if any S() is reduced, another one
1017 * counted must be increased. mss's step operation
1018 * updates K with S(k), so MAX(K', S(k+1)..)=MAX(K, S(k)..),
1019 * and updates k to k+1, preserving the invariant.
1020 * At the end we have k=3 and K=>M. Since secnet never
1021 * invents serials, K=M in the absence of an mss update
1024 * Consideration of the mss update operation:
1025 * Successive serials from sites file updates etc. are supposed
1026 * to be increasing. When this is true, M is increased. A
1027 * concurrent reading mss which makes its first read after the
1028 * update will get the new data (by the proofs above). This
1029 * seems to be the required property.
1033 * [1] From "Base Specifications issue 7",
1034 * 2.9.7 Thread Interactions with Regular File Operations
1035 * All of the following functions shall be atomic with respect to
1036 * each other in the effects specified in POSIX.1-2017 when they
1037 * operate on regular files or symbolic links:
1038 * ... rename ... open ...
1040 if (!st->peerkeys_path) return;
1042 pathprefix_template_setsuffix(&st->peerkeys_tmpl,"~proc");
1043 peerkeys_maybe_incorporate(st,st->peerkeys_tmpl.buffer,
1044 " (found old update)",
1047 pathprefix_template_setsuffix(&st->peerkeys_tmpl,"~update");
1048 const char *inputp=st->peerkeys_tmpl.buffer;
1049 if (access(inputp,R_OK)) {
1051 slog(st,LOG_ERROR,"cannot access peer key update file %s\n",
1056 buffer_init(&st->scratch,0);
1057 BUF_ADD_BYTES(append,&st->scratch,
1058 st->peerkeys_tmpl.buffer,
1059 strlen(st->peerkeys_tmpl.buffer)+1);
1060 inputp=st->scratch.start;
1062 pathprefix_template_setsuffix(&st->peerkeys_tmpl,"~proc");
1063 const char *oursp=st->peerkeys_tmpl.buffer;
1065 int r=rename(inputp,oursp);
1067 slog(st,LOG_ERROR,"failed to claim key update file %s as %s: %s\n",
1068 inputp,oursp,strerror(errno));
1072 peerkeys_maybe_incorporate(st,oursp," (update)",M_ERR);
1076 static bool_t kex_init(struct site *st)
1078 keyset_dispose(&st->peerkeys_kex);
1079 peerkeys_check_for_update(st);
1080 if (!st->peerkeys_current) {
1081 slog(st,LOG_SETUP_INIT,"no peer public keys, abandoning key setup");
1084 st->peerkeys_kex = keyset_dup(st->peerkeys_current);
1085 st->random->generate(st->random->st,NONCELEN,st->localN);
1089 static bool_t generate_msg1(struct site *st, const struct msg *prompt_maybe_0)
1092 generate_msg(st,LABEL_MSG1,"site:MSG1",prompt_maybe_0);
1095 static bool_t process_msg1(struct site *st, struct buffer_if *msg1,
1096 const struct comm_addr *src,
1097 const struct msg *m)
1099 /* We've already determined we're in an appropriate state to
1100 process an incoming MSG1, and that the MSG1 has correct values
1103 st->setup_session_id=m->source;
1104 st->remote_capabilities=m->remote_capabilities;
1105 memcpy(st->remoteN,m->nR,NONCELEN);
1109 static bool_t generate_msg2(struct site *st,
1110 const struct msg *prompt_may_be_null)
1113 generate_msg(st,LABEL_MSG2,"site:MSG2",prompt_may_be_null);
1116 static bool_t process_msg2(struct site *st, struct buffer_if *msg2,
1117 const struct comm_addr *src,
1118 struct msg *m /* returned */)
1122 if (!unpick_msg(st,LABEL_MSG2,msg2,m)) return False;
1123 if (!check_msg(st,LABEL_MSG2,m,&err)) {
1124 slog(st,LOG_SEC,"msg2: %s",err);
1127 st->setup_session_id=m->source;
1128 st->remote_capabilities=m->remote_capabilities;
1130 /* Select the transform to use */
1132 uint32_t remote_crypto_caps = st->remote_capabilities & CAPAB_TRANSFORM_MASK;
1133 if (!remote_crypto_caps)
1134 /* old secnets only had this one transform */
1135 remote_crypto_caps = 1UL << CAPAB_BIT_ANCIENTTRANSFORM;
1137 #define CHOOSE_CRYPTO(kind, whats) do { \
1138 struct kind##_if *iface; \
1139 uint32_t bit, ours = 0; \
1141 for (i= 0; i < st->n##kind##s; i++) { \
1142 iface=st->kind##s[i]; \
1143 bit = 1UL << iface->capab_bit; \
1144 if (bit & remote_crypto_caps) goto kind##_found; \
1147 slog(st,LOG_ERROR,"no " whats " in common" \
1148 " (us %#"PRIx32"; them: %#"PRIx32")", \
1149 st->local_capabilities & ours, remote_crypto_caps); \
1152 st->chosen_##kind = iface; \
1155 CHOOSE_CRYPTO(transform, "transforms");
1157 #undef CHOOSE_CRYPTO
1159 memcpy(st->remoteN,m->nR,NONCELEN);
1163 static bool_t generate_msg3(struct site *st, const struct msg *prompt)
1165 /* Now we have our nonce and their nonce. Think of a secret key,
1166 and create message number 3. */
1167 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
1168 return generate_msg(st,
1169 (st->remote_capabilities & CAPAB_TRANSFORM_MASK)
1172 "site:MSG3",prompt);
1175 static bool_t process_msg3_msg4(struct site *st, struct msg *m)
1177 /* Check signature and store g^x mod m */
1180 if (m->signing_key_index >= 0) {
1181 if (m->signing_key_index >= st->peerkeys_kex->nkeys)
1183 ki=m->signing_key_index;
1185 for (ki=0; ki<st->peerkeys_kex->nkeys; ki++)
1186 if (sigkeyid_equal(&keyid_zero,&st->peerkeys_kex->keys[ki].id))
1190 "peer signed with keyid zero, which we do not accept");
1194 struct sigpubkey_if *pubkey=st->peerkeys_kex->keys[ki].pubkey;
1196 if (!pubkey->check(pubkey->st,
1197 m->hashstart,m->hashlen,
1199 slog(st,LOG_SEC,"msg3/msg4 signature failed check!");
1203 st->remote_adv_mtu=m->remote_mtu;
1208 static bool_t process_msg3(struct site *st, struct buffer_if *msg3,
1209 const struct comm_addr *src, uint32_t msgtype,
1210 struct msg *m /* returned */)
1215 case CASES_MSG3_KNOWN: break;
1219 if (!unpick_msg(st,msgtype,msg3,m)) return False;
1220 if (!check_msg(st,msgtype,m,&err)) {
1221 slog(st,LOG_SEC,"msg3: %s",err);
1224 uint32_t capab_adv_late = m->remote_capabilities
1225 & ~st->remote_capabilities & st->early_capabilities;
1226 if (capab_adv_late) {
1227 slog(st,LOG_SEC,"msg3 impermissibly adds early capability flag(s)"
1228 " %#"PRIx32" (was %#"PRIx32", now %#"PRIx32")",
1229 capab_adv_late, st->remote_capabilities, m->remote_capabilities);
1233 #define CHOSE_CRYPTO(kind, what) do { \
1234 struct kind##_if *iface; \
1236 for (i=0; i<st->n##kind##s; i++) { \
1237 iface=st->kind##s[i]; \
1238 if (iface->capab_bit == m->capab_##kind##num) \
1239 goto kind##_found; \
1241 slog(st,LOG_SEC,"peer chose unknown-to-us " what " %d!", \
1242 m->capab_##kind##num); \
1245 st->chosen_##kind=iface; \
1248 CHOSE_CRYPTO(transform, "transform");
1252 if (!process_msg3_msg4(st,m))
1255 /* Update our idea of the remote site's capabilities, now that we've
1256 * verified that its message was authentic.
1258 * Our previous idea of the remote site's capabilities came from the
1259 * unauthenticated MSG1. We've already checked that this new message
1260 * doesn't change any of the bits we relied upon in the past, but it may
1261 * also have set additional capability bits. We simply throw those away
1262 * now, and use the authentic capabilities from this MSG3. */
1263 st->remote_capabilities=m->remote_capabilities;
1265 /* Terminate their DH public key with a '0' */
1267 /* Invent our DH secret key */
1268 st->random->generate(st->random->st,st->dh->len,st->dhsecret);
1270 /* Generate the shared key and set up the transform */
1271 if (!set_new_transform(st,m->pk)) return False;
1276 static bool_t generate_msg4(struct site *st, const struct msg *prompt)
1278 /* We have both nonces, their public key and our private key. Generate
1279 our public key, sign it and send it to them. */
1280 return generate_msg(st,LABEL_MSG4,"site:MSG4",prompt);
1283 static bool_t process_msg4(struct site *st, struct buffer_if *msg4,
1284 const struct comm_addr *src,
1285 struct msg *m /* returned */)
1289 if (!unpick_msg(st,LABEL_MSG4,msg4,m)) return False;
1290 if (!check_msg(st,LABEL_MSG4,m,&err)) {
1291 slog(st,LOG_SEC,"msg4: %s",err);
1295 if (!process_msg3_msg4(st,m))
1298 /* Terminate their DH public key with a '0' */
1301 /* Generate the shared key and set up the transform */
1302 if (!set_new_transform(st,m->pk)) return False;
1313 static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0,
1316 CHECK_AVAIL(msg0,4);
1317 m->dest=buf_unprepend_uint32(msg0);
1318 CHECK_AVAIL(msg0,4);
1319 m->source=buf_unprepend_uint32(msg0);
1320 CHECK_AVAIL(msg0,4);
1321 m->type=buf_unprepend_uint32(msg0);
1323 /* Leaves transformed part of buffer untouched */
1326 static bool_t generate_msg5(struct site *st, const struct msg *prompt)
1328 cstring_t transform_err;
1330 BUF_ALLOC(&st->buffer,"site:MSG5");
1331 /* We are going to add four words to the message */
1332 buffer_init(&st->buffer,calculate_max_start_pad());
1333 /* Give the netlink code an opportunity to put its own stuff in the
1334 message (configuration information, etc.) */
1335 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
1336 if (call_transform_forwards(st,st->new_transform,
1337 &st->buffer,&transform_err))
1339 buf_prepend_uint32(&st->buffer,LABEL_MSG5);
1340 buf_prepend_uint32(&st->buffer,st->index);
1341 buf_prepend_uint32(&st->buffer,st->setup_session_id);
1343 st->retries=st->setup_retries;
1347 static bool_t process_msg5(struct site *st, struct buffer_if *msg5,
1348 const struct comm_addr *src,
1349 struct transform_inst_if *transform)
1352 cstring_t transform_err;
1354 if (!unpick_msg0(st,msg5,&m)) return False;
1356 if (call_transform_reverse(st,transform,msg5,&transform_err)) {
1357 /* There's a problem */
1358 slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err);
1361 /* Buffer should now contain untransformed PING packet data */
1362 CHECK_AVAIL(msg5,4);
1363 if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) {
1364 slog(st,LOG_SEC,"MSG5/PING packet contained wrong label");
1367 /* Older versions of secnet used to write some config data here
1368 * which we ignore. So we don't CHECK_EMPTY */
1372 static void create_msg6(struct site *st, struct transform_inst_if *transform,
1373 uint32_t session_id)
1375 cstring_t transform_err;
1377 BUF_ALLOC(&st->buffer,"site:MSG6");
1378 /* We are going to add four words to the message */
1379 buffer_init(&st->buffer,calculate_max_start_pad());
1380 /* Give the netlink code an opportunity to put its own stuff in the
1381 message (configuration information, etc.) */
1382 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1383 transform_apply_return problem =
1384 call_transform_forwards(st,transform,
1385 &st->buffer,&transform_err);
1387 buf_prepend_uint32(&st->buffer,LABEL_MSG6);
1388 buf_prepend_uint32(&st->buffer,st->index);
1389 buf_prepend_uint32(&st->buffer,session_id);
1392 static bool_t generate_msg6(struct site *st, const struct msg *prompt)
1394 if (!is_transform_valid(st->new_transform))
1396 create_msg6(st,st->new_transform,st->setup_session_id);
1397 st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */
1401 static bool_t process_msg6(struct site *st, struct buffer_if *msg6,
1402 const struct comm_addr *src)
1405 cstring_t transform_err;
1407 if (!unpick_msg0(st,msg6,&m)) return False;
1409 if (call_transform_reverse(st,st->new_transform,msg6,&transform_err)) {
1410 /* There's a problem */
1411 slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err);
1414 /* Buffer should now contain untransformed PING packet data */
1415 CHECK_AVAIL(msg6,4);
1416 if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) {
1417 slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data");
1420 /* Older versions of secnet used to write some config data here
1421 * which we ignore. So we don't CHECK_EMPTY */
1425 static transform_apply_return
1426 decrypt_msg0(struct site *st, struct buffer_if *msg0,
1427 const struct comm_addr *src)
1429 cstring_t transform_err, auxkey_err, newkey_err="n/a";
1431 transform_apply_return problem;
1433 if (!unpick_msg0(st,msg0,&m)) return False;
1435 /* Keep a copy so we can try decrypting it with multiple keys */
1436 buffer_copy(&st->scratch, msg0);
1438 problem = call_transform_reverse(st,st->current.transform,
1439 msg0,&transform_err);
1441 if (!st->auxiliary_is_new)
1442 delete_one_key(st,&st->auxiliary_key,
1443 "peer has used new key","auxiliary key",LOG_SEC);
1446 if (transform_apply_return_badseq(problem))
1449 buffer_copy(msg0, &st->scratch);
1450 problem = call_transform_reverse(st,st->auxiliary_key.transform,
1453 slog(st,LOG_DROP,"processing packet which uses auxiliary key");
1454 if (st->auxiliary_is_new) {
1455 /* We previously timed out in state SENTMSG5 but it turns
1456 * out that our peer did in fact get our MSG5 and is
1457 * using the new key. So we should switch to it too. */
1458 /* This is a bit like activate_new_key. */
1461 st->current=st->auxiliary_key;
1462 st->auxiliary_key=t;
1464 delete_one_key(st,&st->auxiliary_key,"peer has used new key",
1465 "previous key",LOG_SEC);
1466 st->auxiliary_is_new=0;
1467 st->renegotiate_key_time=st->auxiliary_renegotiate_key_time;
1471 if (transform_apply_return_badseq(problem))
1474 if (st->state==SITE_SENTMSG5) {
1475 buffer_copy(msg0, &st->scratch);
1476 problem = call_transform_reverse(st,st->new_transform,
1479 /* It looks like we didn't get the peer's MSG6 */
1480 /* This is like a cut-down enter_new_state(SITE_RUN) */
1481 slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)");
1482 BUF_FREE(&st->buffer);
1484 activate_new_key(st);
1485 return 0; /* do process the data in this packet */
1487 if (transform_apply_return_badseq(problem))
1491 slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)",
1492 transform_err,auxkey_err,newkey_err);
1493 initiate_key_setup(st,"incoming message would not decrypt",0);
1494 send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt");
1499 slog(st,LOG_DROP,"transform: %s (bad seq.)",transform_err);
1504 static bool_t process_msg0(struct site *st, struct buffer_if *msg0,
1505 const struct comm_addr *src)
1508 transform_apply_return problem;
1510 problem = decrypt_msg0(st,msg0,src);
1511 if (problem==transform_apply_seqdupe) {
1512 /* We recently received another copy of this packet, maybe due
1513 * to polypath. That's not a problem; indeed, for the
1514 * purposes of transport address management it is a success.
1515 * But we don't want to process the packet. */
1516 transport_data_msgok(st,src);
1522 CHECK_AVAIL(msg0,4);
1523 type=buf_unprepend_uint32(msg0);
1526 /* We must forget about the current session. */
1527 delete_keys(st,"request from peer",LOG_SEC);
1528 /* probably, the peer is shutting down, and this is going to fail,
1529 * but we need to be trying to bring the link up again */
1531 initiate_key_setup(st,"peer requested key teardown",0);
1534 /* Deliver to netlink layer */
1535 st->netlink->deliver(st->netlink->st,msg0);
1536 transport_data_msgok(st,src);
1537 /* See whether we should start negotiating a new key */
1538 if (st->now > st->renegotiate_key_time)
1539 initiate_key_setup(st,"incoming packet in renegotiation window",0);
1542 slog(st,LOG_SEC,"incoming encrypted message of type %08x "
1549 static void dump_packet(struct site *st, struct buffer_if *buf,
1550 const struct comm_addr *addr, bool_t incoming,
1553 uint32_t dest=get_uint32(buf->start);
1554 uint32_t source=get_uint32(buf->start+4);
1555 uint32_t msgtype=get_uint32(buf->start+8);
1557 if (st->log_events & LOG_DUMP)
1558 slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x: %s%s",
1559 st->tunname,incoming?"incoming":"outgoing",
1560 dest,source,msgtype,comm_addr_to_string(addr),
1564 static bool_t comm_addr_sendmsg(struct site *st,
1565 const struct comm_addr *dest,
1566 struct buffer_if *buf)
1569 struct comm_clientinfo *commclientinfo = 0;
1571 for (i=0; i < st->ncomms; i++) {
1572 if (st->comms[i] == dest->comm) {
1573 commclientinfo = st->commclientinfos[i];
1577 return dest->comm->sendmsg(dest->comm->st, buf, dest, commclientinfo);
1580 static uint32_t site_status(void *st)
1585 static bool_t send_msg(struct site *st)
1587 if (st->retries>0) {
1588 transport_xmit(st, &st->setup_peers, &st->buffer, True);
1589 st->timeout=st->now+st->setup_retry_interval;
1592 } else if (st->state==SITE_SENTMSG5) {
1593 logtimeout(st,"timed out sending MSG5, stashing new key");
1594 /* We stash the key we have produced, in case it turns out that
1595 * our peer did see our MSG5 after all and starts using it. */
1596 /* This is a bit like some of activate_new_key */
1597 struct transform_inst_if *t;
1598 t=st->auxiliary_key.transform;
1599 st->auxiliary_key.transform=st->new_transform;
1600 st->new_transform=t;
1601 dispose_transform(&st->new_transform);
1603 st->auxiliary_is_new=1;
1604 st->auxiliary_key.key_timeout=st->now+st->key_lifetime;
1605 st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time;
1606 st->auxiliary_key.remote_session_id=st->setup_session_id;
1608 enter_state_wait(st);
1611 logtimeout(st,"timed out sending key setup packet "
1612 "(in state %s)",state_name(st->state));
1613 enter_state_wait(st);
1618 static void site_resolve_callback(void *sst, const struct comm_addr *addrs,
1619 int stored_naddrs, int all_naddrs,
1620 const char *address, const char *failwhy)
1622 struct site *st=sst;
1624 if (!stored_naddrs) {
1625 slog(st,LOG_ERROR,"resolution of %s failed: %s",address,failwhy);
1627 slog(st,LOG_PEER_ADDRS,"resolution of %s completed, %d addrs, eg: %s",
1628 address, all_naddrs, comm_addr_to_string(&addrs[0]));;
1630 int space=st->transport_peers_max-st->resolving_n_results_stored;
1631 int n_tocopy=MIN(stored_naddrs,space);
1632 COPY_ARRAY(st->resolving_results + st->resolving_n_results_stored,
1635 st->resolving_n_results_stored += n_tocopy;
1636 st->resolving_n_results_all += all_naddrs;
1639 decrement_resolving_count(st,1);
1642 static void decrement_resolving_count(struct site *st, int by)
1644 assert(st->resolving_count>0);
1645 st->resolving_count-=by;
1647 if (st->resolving_count)
1650 /* OK, we are done with them all. Handle combined results. */
1652 const struct comm_addr *addrs=st->resolving_results;
1653 int naddrs=st->resolving_n_results_stored;
1654 assert(naddrs<=st->transport_peers_max);
1657 if (naddrs != st->resolving_n_results_all) {
1658 slog(st,LOG_SETUP_INIT,"resolution of supplied addresses/names"
1659 " yielded too many results (%d > %d), some ignored",
1660 st->resolving_n_results_all, naddrs);
1662 slog(st,LOG_STATE,"resolution completed, %d addrs, eg: %s",
1663 naddrs, iaddr_to_string(&addrs[0].ia));;
1666 switch (st->state) {
1668 if (transport_compute_setupinit_peers(st,addrs,naddrs,0)) {
1669 enter_new_state(st,SITE_SENTMSG1,0);
1671 /* Can't figure out who to try to to talk to */
1672 slog(st,LOG_SETUP_INIT,
1673 "key exchange failed: cannot find peer address");
1674 enter_state_run(st);
1677 case SITE_SENTMSG1: case SITE_SENTMSG2:
1678 case SITE_SENTMSG3: case SITE_SENTMSG4:
1681 /* We start using the address immediately for data too.
1682 * It's best to store it in st->peers now because we might
1683 * go via SENTMSG5, WAIT, and a MSG0, straight into using
1684 * the new key (without updating the data peer addrs). */
1685 transport_resolve_complete(st,addrs,naddrs);
1686 } else if (st->local_mobile) {
1687 /* We can't let this rest because we may have a peer
1688 * address which will break in the future. */
1689 slog(st,LOG_SETUP_INIT,"resolution failed: "
1690 "abandoning key exchange");
1691 enter_state_wait(st);
1693 slog(st,LOG_SETUP_INIT,"resolution failed: "
1694 " continuing to use source address of peer's packets"
1695 " for key exchange and ultimately data");
1700 slog(st,LOG_SETUP_INIT,"resolution completed tardily,"
1701 " updating peer address(es)");
1702 transport_resolve_complete_tardy(st,addrs,naddrs);
1703 } else if (st->local_mobile) {
1704 /* Not very good. We should queue (another) renegotiation
1705 * so that we can update the peer address. */
1706 st->key_renegotiate_time=st->now+wait_timeout(st);
1708 slog(st,LOG_SETUP_INIT,"resolution failed: "
1709 " continuing to use source address of peer's packets");
1719 static bool_t initiate_key_setup(struct site *st, cstring_t reason,
1720 const struct comm_addr *prod_hint)
1722 /* Reentrancy hazard: can call enter_new_state/enter_state_* */
1723 if (st->state!=SITE_RUN) return False;
1724 slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason);
1725 if (st->addresses) {
1726 slog(st,LOG_SETUP_INIT,"resolving peer address(es)");
1727 return enter_state_resolve(st);
1728 } else if (transport_compute_setupinit_peers(st,0,0,prod_hint)) {
1729 return enter_new_state(st,SITE_SENTMSG1,0);
1731 slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer");
1735 static void activate_new_key(struct site *st)
1737 struct transform_inst_if *t;
1739 /* We have three transform instances, which we swap between old,
1741 t=st->auxiliary_key.transform;
1742 st->auxiliary_key.transform=st->current.transform;
1743 st->current.transform=st->new_transform;
1744 st->new_transform=t;
1745 dispose_transform(&st->new_transform);
1748 st->auxiliary_is_new=0;
1749 st->auxiliary_key.key_timeout=st->current.key_timeout;
1750 st->current.key_timeout=st->now+st->key_lifetime;
1751 st->renegotiate_key_time=st->now+st->key_renegotiate_time;
1752 transport_peers_copy(st,&st->peers,&st->setup_peers);
1753 st->current.remote_session_id=st->setup_session_id;
1755 /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
1756 * But their mtu be unspecified, in which case we just use ours. */
1757 uint32_t intersite_mtu=
1758 MIN(st->mtu_target, st->remote_adv_mtu ?: ~(uint32_t)0);
1759 st->netlink->set_mtu(st->netlink->st,intersite_mtu);
1761 slog(st,LOG_ACTIVATE_KEY,"new key activated"
1762 " (mtu ours=%"PRId32" theirs=%"PRId32" intersite=%"PRId32")",
1763 st->mtu_target, st->remote_adv_mtu, intersite_mtu);
1764 enter_state_run(st);
1767 static void delete_one_key(struct site *st, struct data_key *key,
1768 cstring_t reason, cstring_t which, uint32_t loglevel)
1770 if (!is_transform_valid(key->transform)) return;
1771 if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason);
1772 dispose_transform(&key->transform);
1776 static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel)
1778 if (current_valid(st)) {
1779 slog(st,loglevel,"session closed (%s)",reason);
1781 delete_one_key(st,&st->current,0,0,0);
1782 set_link_quality(st);
1784 delete_one_key(st,&st->auxiliary_key,0,0,0);
1787 static void state_assert(struct site *st, bool_t ok)
1789 if (!ok) fatal("site:state_assert");
1792 static void enter_state_stop(struct site *st)
1794 st->state=SITE_STOP;
1796 delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY);
1797 dispose_transform(&st->new_transform);
1800 static void set_link_quality(struct site *st)
1803 if (current_valid(st))
1804 quality=LINK_QUALITY_UP;
1805 else if (st->state==SITE_WAIT || st->state==SITE_STOP)
1806 quality=LINK_QUALITY_DOWN;
1807 else if (st->addresses)
1808 quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS;
1809 else if (transport_peers_valid(&st->peers))
1810 quality=LINK_QUALITY_DOWN_STALE_ADDRESS;
1812 quality=LINK_QUALITY_DOWN;
1814 st->netlink->set_quality(st->netlink->st,quality);
1817 static void enter_state_run(struct site *st)
1819 slog(st,LOG_STATE,"entering state RUN%s",
1820 current_valid(st) ? " (keyed)" : " (unkeyed)");
1824 st->setup_session_id=0;
1825 transport_peers_clear(st,&st->setup_peers);
1826 keyset_dispose(&st->peerkeys_kex);
1827 FILLZERO(st->localN);
1828 FILLZERO(st->remoteN);
1829 dispose_transform(&st->new_transform);
1830 memset(st->dhsecret,0,st->dh->len);
1831 if (st->sharedsecret) memset(st->sharedsecret,0,st->sharedsecretlen);
1832 set_link_quality(st);
1834 if (st->keepalive && !current_valid(st))
1835 initiate_key_setup(st, "keepalive", 0);
1838 static bool_t ensure_resolving(struct site *st)
1840 /* Reentrancy hazard: may call site_resolve_callback and hence
1841 * enter_new_state, enter_state_* and generate_msg*. */
1842 if (st->resolving_count)
1845 assert(st->addresses);
1847 /* resolver->request might reentrantly call site_resolve_callback
1848 * which will decrement st->resolving, so we need to increment it
1849 * twice beforehand to prevent decrement from thinking we're
1850 * finished, and decrement it ourselves. Alternatively if
1851 * everything fails then there are no callbacks due and we simply
1852 * set it to 0 and return false.. */
1853 st->resolving_n_results_stored=0;
1854 st->resolving_n_results_all=0;
1855 st->resolving_count+=2;
1856 const char **addrp=st->addresses;
1857 const char *address;
1859 for (; (address=*addrp++); ) {
1860 bool_t ok = st->resolver->request(st->resolver->st,address,
1861 st->remoteport,st->comms[0],
1862 site_resolve_callback,st);
1864 st->resolving_count++;
1868 st->resolving_count=0;
1871 decrement_resolving_count(st,2);
1875 static bool_t enter_state_resolve(struct site *st)
1877 /* Reentrancy hazard! See ensure_resolving. */
1878 state_assert(st,st->state==SITE_RUN);
1879 slog(st,LOG_STATE,"entering state RESOLVE");
1880 st->state=SITE_RESOLVE;
1881 return ensure_resolving(st);
1884 static bool_t enter_new_state(struct site *st, uint32_t next,
1885 const struct msg *prompt
1886 /* may be 0 for SENTMSG1 */)
1888 bool_t (*gen)(struct site *st, const struct msg *prompt);
1891 slog(st,LOG_STATE,"entering state %s",state_name(next));
1894 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE);
1895 if (!kex_init(st)) return False;
1897 st->msg1_crossed_logged = False;
1900 state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE ||
1901 st->state==SITE_SENTMSG1 || st->state==SITE_WAIT);
1902 if (!kex_init(st)) return False;
1906 state_assert(st,st->state==SITE_SENTMSG1);
1907 BUF_FREE(&st->buffer);
1911 state_assert(st,st->state==SITE_SENTMSG2);
1912 BUF_FREE(&st->buffer);
1916 state_assert(st,st->state==SITE_SENTMSG3);
1917 BUF_FREE(&st->buffer);
1921 state_assert(st,st->state==SITE_SENTMSG4);
1922 BUF_FREE(&st->buffer);
1927 fatal("enter_new_state(%s): invalid new state",state_name(next));
1931 if (hacky_par_start_failnow()) return False;
1933 r= gen(st,prompt) && send_msg(st);
1936 st->setup_retries, st->setup_retry_interval,
1941 if (next==SITE_RUN) {
1942 BUF_FREE(&st->buffer); /* Never reused */
1943 st->timeout=0; /* Never retransmit */
1944 activate_new_key(st);
1948 slog(st,LOG_ERROR,"error entering state %s",state_name(next));
1949 st->buffer.free=False; /* Unconditionally use the buffer; it may be
1950 in either state, and enter_state_wait() will
1952 enter_state_wait(st);
1956 /* msg7 tells our peer that we're about to forget our key */
1957 static bool_t send_msg7(struct site *st, cstring_t reason)
1959 cstring_t transform_err;
1961 if (current_valid(st) && st->buffer.free
1962 && transport_peers_valid(&st->peers)) {
1963 BUF_ALLOC(&st->buffer,"site:MSG7");
1964 buffer_init(&st->buffer,calculate_max_start_pad());
1965 buf_append_uint32(&st->buffer,LABEL_MSG7);
1966 buf_append_string(&st->buffer,reason);
1967 if (call_transform_forwards(st, st->current.transform,
1968 &st->buffer, &transform_err))
1970 buf_prepend_uint32(&st->buffer,LABEL_MSG0);
1971 buf_prepend_uint32(&st->buffer,st->index);
1972 buf_prepend_uint32(&st->buffer,st->current.remote_session_id);
1973 transport_xmit(st,&st->peers,&st->buffer,True);
1974 BUF_FREE(&st->buffer);
1981 /* We go into this state if our peer becomes uncommunicative. Similar to
1982 the "stop" state, we forget all session keys for a while, before
1983 re-entering the "run" state. */
1984 static void enter_state_wait(struct site *st)
1986 slog(st,LOG_STATE,"entering state WAIT");
1987 st->timeout=st->now+wait_timeout(st);
1988 st->state=SITE_WAIT;
1989 set_link_quality(st);
1990 BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */
1991 /* XXX Erase keys etc. */
1994 static void generate_prod(struct site *st, struct buffer_if *buf)
1997 buf_append_uint32(buf,0);
1998 buf_append_uint32(buf,0);
1999 buf_append_uint32(buf,LABEL_PROD);
2000 buf_append_string(buf,st->localname);
2001 buf_append_string(buf,st->remotename);
2004 static void generate_send_prod(struct site *st,
2005 const struct comm_addr *source)
2007 if (!st->allow_send_prod) return; /* too soon */
2008 if (!(st->state==SITE_RUN || st->state==SITE_RESOLVE ||
2009 st->state==SITE_WAIT)) return; /* we'd ignore peer's MSG1 */
2011 slog(st,LOG_SETUP_INIT,"prodding peer for key exchange");
2012 st->allow_send_prod=0;
2013 generate_prod(st,&st->scratch);
2014 bool_t ok = comm_addr_sendmsg(st, source, &st->scratch);
2015 dump_packet(st,&st->scratch,source,False,ok);
2018 static inline void site_settimeout(uint64_t timeout, int *timeout_io)
2021 int64_t offset=timeout-*now;
2022 if (offset<0) offset=0;
2023 if (offset>INT_MAX) offset=INT_MAX;
2024 if (*timeout_io<0 || offset<*timeout_io)
2029 static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io,
2032 struct site *st=sst;
2034 BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
2037 /* Work out when our next timeout is. The earlier of 'timeout' or
2038 'current.key_timeout'. A stored value of '0' indicates no timeout
2040 site_settimeout(st->timeout, timeout_io);
2041 site_settimeout(st->current.key_timeout, timeout_io);
2042 site_settimeout(st->auxiliary_key.key_timeout, timeout_io);
2044 return 0; /* success */
2047 static void check_expiry(struct site *st, struct data_key *key,
2050 if (key->key_timeout && *now>key->key_timeout) {
2051 delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY);
2055 /* NB site_afterpoll will be called before site_beforepoll is ever called */
2056 static void site_afterpoll(void *sst, struct pollfd *fds, int nfds)
2058 struct site *st=sst;
2061 if (st->timeout && *now>st->timeout) {
2063 if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) {
2064 if (!hacky_par_start_failnow())
2066 } else if (st->state==SITE_WAIT) {
2067 enter_state_run(st);
2069 slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d",
2073 check_expiry(st,&st->current,"current key");
2074 check_expiry(st,&st->auxiliary_key,"auxiliary key");
2077 /* This function is called by the netlink device to deliver packets
2078 intended for the remote network. The packet is in "raw" wire
2079 format, but is guaranteed to be word-aligned. */
2080 static void site_outgoing(void *sst, struct buffer_if *buf)
2082 struct site *st=sst;
2083 cstring_t transform_err;
2085 if (st->state==SITE_STOP) {
2090 st->allow_send_prod=1;
2092 /* In all other states we consider delivering the packet if we have
2093 a valid key and a valid address to send it to. */
2094 if (current_valid(st) && transport_peers_valid(&st->peers)) {
2095 /* Transform it and send it */
2097 buf_prepend_uint32(buf,LABEL_MSG9);
2098 if (call_transform_forwards(st, st->current.transform,
2099 buf, &transform_err))
2101 buf_prepend_uint32(buf,LABEL_MSG0);
2102 buf_prepend_uint32(buf,st->index);
2103 buf_prepend_uint32(buf,st->current.remote_session_id);
2104 transport_xmit(st,&st->peers,buf,False);
2111 slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size);
2113 initiate_key_setup(st,"outgoing packet",0);
2116 static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in,
2117 uint32_t type, struct msg *m,
2118 struct priomsg *whynot)
2119 /* For packets which are identified by the local and remote names.
2120 * If it has our name and our peer's name in it it's for us. */
2122 struct buffer_if buf[1];
2123 buffer_readonly_clone(buf,buf_in);
2125 if (!unpick_msg(st,type,buf,m)) {
2126 priomsg_update_fixed(whynot, comm_notify_whynot_unpick, "malformed");
2129 #define NAME_MATCHES(lr) \
2130 if (!name_matches(&m->lr, st->lr##name)) { \
2131 if (priomsg_update_fixed(whynot, comm_notify_whynot_name_##lr, \
2132 "unknown " #lr " name: ")) { \
2133 truncmsg_add_packet_string(&whynot->m, m->lr.len, m->lr.name); \
2137 NAME_MATCHES(remote);
2138 NAME_MATCHES(local );
2144 static bool_t we_have_priority(struct site *st, const struct msg *m) {
2145 if (st->local_capabilities & m->remote_capabilities &
2146 CAPAB_PRIORITY_MOBILE) {
2147 if (st->local_mobile) return True;
2148 if (st-> peer_mobile) return False;
2150 return st->our_name_later;
2153 static bool_t setup_late_msg_ok(struct site *st,
2154 const struct buffer_if *buf_in,
2156 const struct comm_addr *source,
2157 struct msg *m /* returned */) {
2158 /* For setup packets which seem from their type like they are
2159 * late. Maybe they came via a different path. All we do is make
2160 * a note of the sending address, iff they look like they are part
2161 * of the current key setup attempt. */
2162 if (!named_for_us(st,buf_in,msgtype,m,0))
2163 /* named_for_us calls unpick_msg which gets the nonces */
2165 if (!consttime_memeq(m->nR,st->remoteN,NONCELEN) ||
2166 !consttime_memeq(m->nL,st->localN, NONCELEN))
2167 /* spoof ? from stale run ? who knows */
2169 transport_setup_msgok(st,source);
2173 /* This function is called by the communication device to deliver
2174 packets from our peers.
2175 It should return True if the packet is recognised as being for
2176 this current site instance (and should therefore not be processed
2177 by other sites), even if the packet was otherwise ignored. */
2178 static bool_t site_incoming(void *sst, struct buffer_if *buf,
2179 const struct comm_addr *source,
2180 struct priomsg *whynot)
2182 struct site *st=sst;
2184 if (buf->size < 12) return False;
2186 uint32_t dest=get_uint32(buf->start);
2187 uint32_t msgtype=get_uint32(buf->start+8);
2189 /* initialised by named_for_us, or process_msgN for N!=1 */
2191 if (msgtype==LABEL_MSG1) {
2192 if (!named_for_us(st,buf,msgtype,&msg,whynot))
2194 /* It's a MSG1 addressed to us. Decide what to do about it. */
2195 dump_packet(st,buf,source,True,True);
2196 if (st->state==SITE_RUN || st->state==SITE_RESOLVE ||
2197 st->state==SITE_WAIT) {
2198 /* We should definitely process it */
2199 transport_compute_setupinit_peers(st,0,0,source);
2200 if (process_msg1(st,buf,source,&msg)) {
2201 slog(st,LOG_SETUP_INIT,"key setup initiated by peer");
2202 bool_t entered=enter_new_state(st,SITE_SENTMSG2,&msg);
2203 if (entered && st->addresses && st->local_mobile)
2204 /* We must do this as the very last thing, because
2205 the resolver callback might reenter us. */
2206 ensure_resolving(st);
2208 slog(st,LOG_ERROR,"failed to process incoming msg1");
2212 } else if (st->state==SITE_SENTMSG1) {
2213 /* We've just sent a message 1! They may have crossed on
2214 the wire. If we have priority then we ignore the
2215 incoming one, otherwise we process it as usual. */
2216 if (we_have_priority(st,&msg)) {
2218 if (!st->msg1_crossed_logged++)
2219 slog(st,LOG_SETUP_INIT,"crossed msg1s; we are higher "
2220 "priority => ignore incoming msg1");
2223 slog(st,LOG_SETUP_INIT,"crossed msg1s; we are lower "
2224 "priority => use incoming msg1");
2225 if (process_msg1(st,buf,source,&msg)) {
2226 BUF_FREE(&st->buffer); /* Free our old message 1 */
2227 transport_setup_msgok(st,source);
2228 enter_new_state(st,SITE_SENTMSG2,&msg);
2230 slog(st,LOG_ERROR,"failed to process an incoming "
2231 "crossed msg1 (we have low priority)");
2236 } else if (st->state==SITE_SENTMSG2 ||
2237 st->state==SITE_SENTMSG4) {
2238 if (consttime_memeq(msg.nR,st->remoteN,NONCELEN)) {
2239 /* We are ahead in the protocol, but that msg1 had the
2240 * peer's nonce so presumably it is from this key
2241 * exchange run, via a slower route */
2242 transport_setup_msgok(st,source);
2244 slog(st,LOG_UNEXPECTED,"competing incoming message 1");
2249 /* The message 1 was received at an unexpected stage of the
2250 key setup. Well, they lost the race. */
2251 slog(st,LOG_UNEXPECTED,"unexpected incoming message 1");
2255 if (msgtype==LABEL_PROD) {
2256 if (!named_for_us(st,buf,msgtype,&msg,whynot))
2258 dump_packet(st,buf,source,True,True);
2259 if (st->state!=SITE_RUN) {
2260 slog(st,LOG_DROP,"ignoring PROD when not in state RUN");
2261 } else if (current_valid(st)) {
2262 slog(st,LOG_DROP,"ignoring PROD when we think we have a key");
2264 initiate_key_setup(st,"peer sent PROD packet",source);
2269 if (dest==st->index) {
2270 /* Explicitly addressed to us */
2271 if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True,True);
2274 /* If the source is our current peer then initiate a key setup,
2275 because our peer's forgotten the key */
2276 if (get_uint32(buf->start+4)==st->current.remote_session_id) {
2278 initiated = initiate_key_setup(st,"received a NAK",source);
2279 if (!initiated) generate_send_prod(st,source);
2281 slog(st,LOG_SEC,"bad incoming NAK");
2285 process_msg0(st,buf,source);
2288 /* Setup packet: should not have been explicitly addressed
2290 slog(st,LOG_SEC,"incoming explicitly addressed msg1");
2293 /* Setup packet: expected only in state SENTMSG1 */
2294 if (st->state!=SITE_SENTMSG1) {
2295 if ((st->state==SITE_SENTMSG3 ||
2296 st->state==SITE_SENTMSG5) &&
2297 setup_late_msg_ok(st,buf,msgtype,source,&msg))
2299 slog(st,LOG_UNEXPECTED,"unexpected MSG2");
2300 } else if (process_msg2(st,buf,source,&msg)) {
2301 transport_setup_msgok(st,source);
2302 enter_new_state(st,SITE_SENTMSG3,&msg);
2304 slog(st,LOG_SEC,"invalid MSG2");
2307 case CASES_MSG3_KNOWN:
2308 /* Setup packet: expected only in state SENTMSG2 */
2309 if (st->state!=SITE_SENTMSG2) {
2310 if ((st->state==SITE_SENTMSG4) &&
2311 setup_late_msg_ok(st,buf,msgtype,source,&msg))
2313 slog(st,LOG_UNEXPECTED,"unexpected MSG3");
2314 } else if (process_msg3(st,buf,source,msgtype,&msg)) {
2315 transport_setup_msgok(st,source);
2316 enter_new_state(st,SITE_SENTMSG4,&msg);
2318 slog(st,LOG_SEC,"invalid MSG3");
2322 /* Setup packet: expected only in state SENTMSG3 */
2323 if (st->state!=SITE_SENTMSG3) {
2324 if ((st->state==SITE_SENTMSG5) &&
2325 setup_late_msg_ok(st,buf,msgtype,source,&msg))
2327 slog(st,LOG_UNEXPECTED,"unexpected MSG4");
2328 } else if (process_msg4(st,buf,source,&msg)) {
2329 transport_setup_msgok(st,source);
2330 enter_new_state(st,SITE_SENTMSG5,&msg);
2332 slog(st,LOG_SEC,"invalid MSG4");
2336 /* Setup packet: expected only in state SENTMSG4 */
2337 /* (may turn up in state RUN if our return MSG6 was lost
2338 and the new key has already been activated. In that
2339 case we discard it. The peer will realise that we
2340 are using the new key when they see our data packets.
2341 Until then the peer's data packets to us get discarded. */
2342 if (st->state==SITE_SENTMSG4) {
2343 if (process_msg5(st,buf,source,st->new_transform)) {
2344 transport_setup_msgok(st,source);
2345 enter_new_state(st,SITE_RUN,&msg);
2347 slog(st,LOG_SEC,"invalid MSG5");
2349 } else if (st->state==SITE_RUN) {
2350 if (process_msg5(st,buf,source,st->current.transform)) {
2351 slog(st,LOG_DROP,"got MSG5, retransmitting MSG6");
2352 transport_setup_msgok(st,source);
2353 create_msg6(st,st->current.transform,
2354 st->current.remote_session_id);
2355 transport_xmit(st,&st->peers,&st->buffer,True);
2356 BUF_FREE(&st->buffer);
2358 slog(st,LOG_SEC,"invalid MSG5 (in state RUN)");
2361 slog(st,LOG_UNEXPECTED,"unexpected MSG5");
2365 /* Setup packet: expected only in state SENTMSG5 */
2366 if (st->state!=SITE_SENTMSG5) {
2367 slog(st,LOG_UNEXPECTED,"unexpected MSG6");
2368 } else if (process_msg6(st,buf,source)) {
2369 BUF_FREE(&st->buffer); /* Free message 5 */
2370 transport_setup_msgok(st,source);
2371 activate_new_key(st);
2373 slog(st,LOG_SEC,"invalid MSG6");
2377 slog(st,LOG_SEC,"received message of unknown type 0x%08x",
2385 priomsg_update_fixed(whynot, comm_notify_whynot_general,
2386 "not MSG1 or PROD; unknown dest index");
2390 static void site_control(void *vst, bool_t run)
2392 struct site *st=vst;
2393 if (run) enter_state_run(st);
2394 else enter_state_stop(st);
2397 static void site_phase_hook(void *sst, uint32_t newphase)
2399 struct site *st=sst;
2401 /* The program is shutting down; tell our peer */
2402 send_msg7(st,"shutting down");
2405 static void site_childpersist_clearkeys(void *sst, uint32_t newphase)
2407 struct site *st=sst;
2408 dispose_transform(&st->current.transform);
2409 dispose_transform(&st->auxiliary_key.transform);
2410 dispose_transform(&st->new_transform);
2411 /* Not much point overwiting the signing key, since we loaded it
2412 from disk, and it is only valid prospectively if at all,
2414 /* XXX it would be best to overwrite the DH state, because that
2415 _is_ relevant to forward secrecy. However we have no
2416 convenient interface for doing that and in practice gmp has
2417 probably dribbled droppings all over the malloc arena. A good
2418 way to fix this would be to have a privsep child for asymmetric
2419 crypto operations, but that's a task for another day. */
2422 static void setup_sethash(struct site *st, dict_t *dict,
2423 struct hash_if **hash, struct cloc loc,
2424 sig_sethash_fn *sethash, void *sigkey_st) {
2425 if (!*hash) *hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc);
2426 sethash(sigkey_st,*hash);
2428 #define SETUP_SETHASH(k) do{ \
2430 setup_sethash(st,dict, &hash,loc, (k)->sethash,(k)->st); \
2433 static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context,
2436 static uint32_t index_sequence;
2444 st->cl.description="site";
2445 st->cl.type=CL_SITE;
2447 st->cl.interface=&st->ops;
2449 st->ops.control=site_control;
2450 st->ops.status=site_status;
2451 st->peerkeys_path=0;
2452 st->peerkeys_tmpl.buffer=0;
2453 st->peerkeys_current=st->peerkeys_kex=0;
2455 /* First parameter must be a dict */
2456 item=list_elem(args,0);
2457 if (!item || item->type!=t_dict)
2458 cfgfatal(loc,"site","parameter must be a dictionary\n");
2460 dict=item->data.dict;
2461 st->localname=dict_read_string(dict, "local-name", True, "site", loc);
2462 st->remotename=dict_read_string(dict, "name", True, "site", loc);
2464 st->keepalive=dict_read_bool(dict,"keepalive",False,"site",loc,False);
2466 st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False);
2468 dict_read_bool(dict,"local-mobile",False,"site",loc,False);
2470 /* Sanity check (which also allows the 'sites' file to include
2471 site() closures for all sites including our own): refuse to
2472 talk to ourselves */
2473 if (strcmp(st->localname,st->remotename)==0) {
2474 Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n",
2476 if (st->peer_mobile != st->local_mobile)
2477 cfgfatal(loc,"site","site %s's peer-mobile=%d"
2478 " but our local-mobile=%d\n",
2479 st->localname, st->peer_mobile, st->local_mobile);
2483 if (st->peer_mobile && st->local_mobile) {
2484 Message(M_WARNING,"site %s: site is mobile but so are we"
2485 " -> ignoring this site\n", st->remotename);
2490 assert(index_sequence < 0xffffffffUL);
2491 st->index = ++index_sequence;
2492 st->local_capabilities = 0;
2493 st->early_capabilities = CAPAB_PRIORITY_MOBILE;
2494 st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc);
2496 #define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
2497 list_t *things##_cfg=dict_lookup(dict,dictkey); \
2498 if (!things##_cfg) \
2499 cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
2500 st->nthings=list_length(things##_cfg); \
2501 NEW_ARY(st->things,st->nthings); \
2502 assert(st->nthings); \
2503 for (i=0; i<st->nthings; i++) { \
2504 item_t *item=list_elem(things##_cfg,i); \
2505 if (item->type!=t_closure) \
2506 cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
2507 closure_t *cl=item->data.closure; \
2508 if (cl->type!=CL_TYPE) \
2509 cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
2510 st->things[i]=cl->interface; \
2514 GET_CLOSURE_LIST("comm",comms,ncomms,CL_COMM);
2516 NEW_ARY(st->commclientinfos, st->ncomms);
2517 dict_t *comminfo = dict_read_dict(dict,"comm-info",False,"site",loc);
2518 for (i=0; i<st->ncomms; i++) {
2519 st->commclientinfos[i] =
2521 st->comms[i]->clientinfo(st->comms[i],comminfo,loc);
2524 st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc);
2525 st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc);
2526 st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc);
2528 struct hash_if *hash=0;
2530 st->privkeys=find_cl_if(dict,"key-cache",CL_PRIVCACHE,False,"site",loc);
2531 if (!st->privkeys) {
2533 find_cl_if(dict,"local-key",CL_SIGPRIVKEY,True,"site",loc);
2534 SETUP_SETHASH(st->privkey_fixed);
2537 struct sigpubkey_if *fixed_pubkey
2538 =find_cl_if(dict,"key",CL_SIGPUBKEY,False,"site",loc);
2539 st->peerkeys_path=dict_read_string(dict,"peer-keys",fixed_pubkey==0,
2541 if (st->peerkeys_path) {
2542 pathprefix_template_init(&st->peerkeys_tmpl,st->peerkeys_path,
2543 PEERKEYS_SUFFIX_MAXLEN + 1 /* nul */);
2544 st->peerkeys_current=keyset_load(st->peerkeys_path,
2545 &st->scratch,st->log,M_ERR);
2547 fixed_pubkey->dispose(fixed_pubkey->st);
2550 assert(fixed_pubkey);
2551 SETUP_SETHASH(fixed_pubkey);
2552 NEW(st->peerkeys_current);
2553 st->peerkeys_current->refcount=1;
2554 st->peerkeys_current->nkeys=1;
2555 st->peerkeys_current->keys[0].id=keyid_zero;
2556 st->peerkeys_current->keys[0].pubkey=fixed_pubkey;
2557 slog(st,LOG_SIGKEYS,
2558 "using old-style fixed peer public key (no `peer-keys')");
2561 st->addresses=dict_read_string_array(dict,"address",False,"site",loc,0);
2563 st->remoteport=dict_read_number(dict,"port",True,"site",loc,0);
2564 else st->remoteport=0;
2566 GET_CLOSURE_LIST("transform",transforms,ntransforms,CL_TRANSFORM);
2568 st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc);
2570 #define DEFAULT(D) (st->peer_mobile || st->local_mobile \
2571 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
2572 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
2574 st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME);
2575 st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES);
2576 st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL);
2577 st->wait_timeout_mean= CFG_NUMBER("wait-time", WAIT_TIME);
2578 st->mtu_target= dict_read_number(dict,"mtu-target",False,"site",loc,0);
2580 st->mobile_peer_expiry= dict_read_number(
2581 dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY);
2583 const char *peerskey= st->peer_mobile
2584 ? "mobile-peers-max" : "static-peers-max";
2585 st->transport_peers_max= dict_read_number(
2586 dict,peerskey,False,"site",loc, st->addresses ? 4 : 3);
2587 if (st->transport_peers_max<1 ||
2588 st->transport_peers_max>MAX_PEER_ADDRS) {
2589 cfgfatal(loc,"site", "%s must be in range 1.."
2590 STRING(MAX_PEER_ADDRS) "\n", peerskey);
2593 if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2)
2594 st->key_renegotiate_time=st->key_lifetime/2;
2596 st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP);
2597 st->key_renegotiate_time=dict_read_number(
2598 dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time);
2599 if (st->key_renegotiate_time > st->key_lifetime) {
2600 cfgfatal(loc,"site",
2601 "renegotiate-time must be less than key-lifetime\n");
2604 st->log_events=string_list_to_word(dict_lookup(dict,"log-events"),
2605 log_event_table,"site");
2607 st->resolving_count=0;
2608 st->allow_send_prod=0;
2610 st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5,
2612 sprintf(st->tunname,"%s<->%s",st->localname,st->remotename);
2614 /* The information we expect to see in incoming messages of type 1 */
2615 /* fixme: lots of unchecked overflows here, but the results are only
2616 corrupted packets rather than undefined behaviour */
2617 st->our_name_later=(strcmp(st->localname,st->remotename)>0);
2619 buffer_new(&st->buffer,SETUP_BUFFER_LEN);
2621 buffer_new(&st->scratch,SETUP_BUFFER_LEN);
2622 BUF_ALLOC(&st->scratch,"site:scratch");
2624 /* We are interested in poll(), but only for timeouts. We don't have
2625 any fds of our own. */
2626 register_for_poll(st, site_beforepoll, site_afterpoll, "site");
2629 st->remote_capabilities=0;
2630 st->chosen_transform=0;
2631 st->current.key_timeout=0;
2632 st->auxiliary_key.key_timeout=0;
2633 transport_peers_clear(st,&st->peers);
2634 transport_peers_clear(st,&st->setup_peers);
2635 /* XXX mlock these */
2636 st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret");
2637 st->sharedsecretlen=st->sharedsecretallocd=0;
2640 #define SET_CAPBIT(bit) do { \
2641 uint32_t capflag = 1UL << (bit); \
2642 if (st->local_capabilities & capflag) \
2643 slog(st,LOG_ERROR,"capability bit" \
2644 " %d (%#"PRIx32") reused", (bit), capflag); \
2645 st->local_capabilities |= capflag; \
2648 for (i=0; i<st->ntransforms; i++)
2649 SET_CAPBIT(st->transforms[i]->capab_bit);
2653 if (st->local_mobile || st->peer_mobile)
2654 st->local_capabilities |= CAPAB_PRIORITY_MOBILE;
2656 /* We need to register the remote networks with the netlink device */
2657 uint32_t netlink_mtu; /* local virtual interface mtu */
2658 st->netlink->reg(st->netlink->st, site_outgoing, st, &netlink_mtu);
2659 if (!st->mtu_target)
2660 st->mtu_target=netlink_mtu;
2662 for (i=0; i<st->ncomms; i++)
2663 st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming);
2665 st->current.transform=0;
2666 st->auxiliary_key.transform=0;
2667 st->new_transform=0;
2668 st->auxiliary_is_new=0;
2670 enter_state_stop(st);
2672 add_hook(PHASE_SHUTDOWN,site_phase_hook,st);
2673 add_hook(PHASE_CHILDPERSIST,site_childpersist_clearkeys,st);
2675 return new_closure(&st->cl);
2678 void site_module(dict_t *dict)
2680 add_closure(dict,"site",site_apply);
2684 /***** TRANSPORT PEERS definitions *****/
2686 static void transport_peers_debug(struct site *st, transport_peers *dst,
2687 const char *didwhat,
2688 int nargs, const struct comm_addr *args,
2693 if (!(st->log_events & LOG_PEER_ADDRS))
2694 return; /* an optimisation */
2696 slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d",
2697 (dst==&st->peers ? "data" :
2698 dst==&st->setup_peers ? "setup" : "UNKNOWN"),
2699 didwhat, nargs, dst->npeers);
2701 for (i=0, argp=(void*)args;
2703 i++, (argp+=stride?stride:sizeof(*args))) {
2704 const struct comm_addr *ca=(void*)argp;
2705 slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s",
2706 i, comm_addr_to_string(ca));
2708 for (i=0; i<dst->npeers; i++) {
2709 struct timeval diff;
2710 timersub(tv_now,&dst->peers[i].last,&diff);
2711 const struct comm_addr *ca=&dst->peers[i].addr;
2712 slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld",
2713 i, comm_addr_to_string(ca),
2714 (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec);
2718 static void transport_peers_expire(struct site *st, transport_peers *peers) {
2719 /* peers must be sorted first */
2720 int previous_peers=peers->npeers;
2721 struct timeval oldest;
2722 oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry;
2723 oldest.tv_usec = tv_now->tv_usec;
2724 while (peers->npeers>1 &&
2725 timercmp(&peers->peers[peers->npeers-1].last, &oldest, <))
2727 if (peers->npeers != previous_peers)
2728 transport_peers_debug(st,peers,"expire", 0,0,0);
2731 static bool_t transport_peer_record_one(struct site *st, transport_peers *peers,
2732 const struct comm_addr *ca,
2733 const struct timeval *tv) {
2734 /* returns false if output is full */
2737 if (peers->npeers >= st->transport_peers_max)
2740 for (search=0; search<peers->npeers; search++)
2741 if (comm_addr_equal(&peers->peers[search].addr, ca))
2744 peers->peers[peers->npeers].addr = *ca;
2745 peers->peers[peers->npeers].last = *tv;
2750 static void transport_record_peers(struct site *st, transport_peers *peers,
2751 const struct comm_addr *addrs, int naddrs,
2753 /* We add addrs into peers. The new entries end up at the front
2754 * and displace entries towards the end (perhaps even off the
2755 * end). Any existing matching entries are moved up to the front.
2757 * Caller must first call transport_peers_expire. */
2760 /* avoids debug for uninteresting updates */
2762 for (i=0; i<peers->npeers; i++) {
2763 if (comm_addr_equal(&addrs[0], &peers->peers[i].addr)) {
2764 memmove(peers->peers+1, peers->peers,
2765 sizeof(peers->peers[0]) * i);
2766 peers->peers[0].addr = addrs[0];
2767 peers->peers[0].last = *tv_now;
2773 int old_npeers=peers->npeers;
2774 transport_peer old_peers[old_npeers];
2775 COPY_ARRAY(old_peers,peers->peers,old_npeers);
2779 for (i=0; i<naddrs; i++) {
2780 if (!transport_peer_record_one(st,peers, &addrs[i], tv_now))
2783 for (i=0; i<old_npeers; i++) {
2784 const transport_peer *old=&old_peers[i];
2785 if (!transport_peer_record_one(st,peers, &old->addr, &old->last))
2789 transport_peers_debug(st,peers,m, naddrs,addrs,0);
2792 static void transport_expire_record_peers(struct site *st,
2793 transport_peers *peers,
2794 const struct comm_addr *addrs,
2795 int naddrs, const char *m) {
2796 /* Convenience function */
2797 transport_peers_expire(st,peers);
2798 transport_record_peers(st,peers,addrs,naddrs,m);
2801 static bool_t transport_compute_setupinit_peers(struct site *st,
2802 const struct comm_addr *configured_addrs /* 0 if none or not found */,
2803 int n_configured_addrs /* 0 if none or not found */,
2804 const struct comm_addr *incoming_packet_addr /* 0 if none */) {
2805 if (!n_configured_addrs && !incoming_packet_addr &&
2806 !transport_peers_valid(&st->peers))
2809 slog(st,LOG_SETUP_INIT,
2810 "using: %d configured addr(s);%s %d old peer addrs(es)",
2812 incoming_packet_addr ? " incoming packet address;" : "",
2815 /* Non-mobile peers try addresses until one is plausible. The
2816 * effect is that this code always tries first the configured
2817 * address if supplied, or otherwise the address of the incoming
2818 * PROD, or finally the existing data peer if one exists; this is
2821 transport_peers_copy(st,&st->setup_peers,&st->peers);
2822 transport_peers_expire(st,&st->setup_peers);
2824 if (incoming_packet_addr)
2825 transport_record_peers(st,&st->setup_peers,
2826 incoming_packet_addr,1, "incoming");
2828 if (n_configured_addrs)
2829 transport_record_peers(st,&st->setup_peers,
2830 configured_addrs,n_configured_addrs, "setupinit");
2832 assert(transport_peers_valid(&st->setup_peers));
2836 static void transport_setup_msgok(struct site *st, const struct comm_addr *a) {
2837 if (st->peer_mobile)
2838 transport_expire_record_peers(st,&st->setup_peers,a,1,"setupmsg");
2840 static void transport_data_msgok(struct site *st, const struct comm_addr *a) {
2841 if (st->peer_mobile)
2842 transport_expire_record_peers(st,&st->peers,a,1,"datamsg");
2845 static int transport_peers_valid(transport_peers *peers) {
2846 return peers->npeers;
2848 static void transport_peers_clear(struct site *st, transport_peers *peers) {
2850 transport_peers_debug(st,peers,"clear",0,0,0);
2852 static void transport_peers_copy(struct site *st, transport_peers *dst,
2853 const transport_peers *src) {
2854 dst->npeers=src->npeers;
2855 COPY_ARRAY(dst->peers, src->peers, dst->npeers);
2856 transport_peers_debug(st,dst,"copy",
2857 src->npeers, &src->peers->addr, sizeof(*src->peers));
2860 static void transport_resolve_complete(struct site *st,
2861 const struct comm_addr *addrs,
2863 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2865 transport_expire_record_peers(st,&st->setup_peers,addrs,naddrs,
2869 static void transport_resolve_complete_tardy(struct site *st,
2870 const struct comm_addr *addrs,
2872 transport_expire_record_peers(st,&st->peers,addrs,naddrs,
2873 "resolved tardily");
2876 static void transport_peers__copy_by_mask(transport_peer *out, int *nout_io,
2878 const transport_peers *inp) {
2879 /* out and in->peers may be the same region, or nonoverlapping */
2880 const transport_peer *in=inp->peers;
2882 for (slot=0; slot<inp->npeers; slot++) {
2883 if (!(mask & (1U << slot)))
2885 if (!(out==in && slot==*nout_io))
2886 COPY_OBJ(out[*nout_io], in[slot]);
2891 void transport_xmit(struct site *st, transport_peers *peers,
2892 struct buffer_if *buf, bool_t candebug) {
2894 transport_peers_expire(st, peers);
2895 unsigned failed=0; /* bitmask */
2896 assert(MAX_PEER_ADDRS < sizeof(unsigned)*CHAR_BIT);
2899 for (slot=0; slot<peers->npeers; slot++) {
2900 transport_peer *peer=&peers->peers[slot];
2901 bool_t ok = comm_addr_sendmsg(st, &peer->addr, buf);
2903 dump_packet(st, buf, &peer->addr, False, ok);
2905 failed |= 1U << slot;
2908 if (ok && !st->peer_mobile)
2911 /* Now we need to demote/delete failing addrs: if we are mobile we
2912 * merely demote them; otherwise we delete them. */
2913 if (st->local_mobile) {
2914 unsigned expected = ((1U << nfailed)-1) << (peers->npeers-nfailed);
2915 /* `expected' has all the failures at the end already */
2916 if (failed != expected) {
2918 transport_peer failedpeers[nfailed];
2919 transport_peers__copy_by_mask(failedpeers, &fslot, failed,peers);
2920 assert(fslot == nfailed);
2922 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2923 assert(wslot+nfailed == peers->npeers);
2924 COPY_ARRAY(peers->peers+wslot, failedpeers, nfailed);
2925 transport_peers_debug(st,peers,"mobile failure reorder",0,0,0);
2928 if (failed && peers->npeers > 1) {
2930 transport_peers__copy_by_mask(peers->peers,&wslot,~failed,peers);
2931 peers->npeers=wslot;
2932 transport_peers_debug(st,peers,"non-mobile failure cleanup",0,0,0);
2937 /***** END of transport peers declarations *****/