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_mean
; /* 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 our_name_later
; /* our name > peer name */
334 /* runtime information */
336 uint64_t now
; /* Most recently seen time */
337 bool_t allow_send_prod
;
338 bool_t msg1_crossed_logged
;
340 int resolving_n_results_all
;
341 int resolving_n_results_stored
;
342 struct comm_addr resolving_results
[MAX_PEER_ADDRS
];
344 /* The currently established session */
345 struct data_key current
;
346 struct data_key auxiliary_key
;
347 bool_t auxiliary_is_new
;
348 uint64_t renegotiate_key_time
; /* When we can negotiate a new key */
349 uint64_t auxiliary_renegotiate_key_time
;
350 transport_peers peers
; /* Current address(es) of peer for data traffic */
352 /* The current key setup protocol exchange. We can only be
353 involved in one of these at a time. There's a potential for
354 denial of service here (the attacker keeps sending a setup
355 packet; we keep trying to continue the exchange, and have to
356 timeout before we can listen for another setup packet); perhaps
357 we should keep a list of 'bad' sources for setup packets. */
358 uint32_t remote_capabilities
;
359 uint16_t remote_adv_mtu
;
360 struct transform_if
*chosen_transform
;
361 uint32_t setup_session_id
;
362 transport_peers setup_peers
;
363 uint8_t localN
[NONCELEN
]; /* Nonces for key exchange */
364 uint8_t remoteN
[NONCELEN
];
365 struct buffer_if buffer
; /* Current outgoing key exchange packet */
366 struct buffer_if scratch
;
367 int32_t retries
; /* Number of retries remaining */
368 uint64_t timeout
; /* Timeout for current state */
370 uint8_t *sharedsecret
;
371 uint32_t sharedsecretlen
, sharedsecretallocd
;
372 struct transform_inst_if
*new_transform
; /* For key setup/verify */
375 static uint32_t event_log_priority(struct site
*st
, uint32_t event
)
377 if (!(event
&st
->log_events
))
380 case LOG_UNEXPECTED
: return M_INFO
;
381 case LOG_SETUP_INIT
: return M_INFO
;
382 case LOG_SETUP_TIMEOUT
: return M_NOTICE
;
383 case LOG_ACTIVATE_KEY
: return M_INFO
;
384 case LOG_TIMEOUT_KEY
: return M_INFO
;
385 case LOG_SEC
: return M_SECURITY
;
386 case LOG_STATE
: return M_DEBUG
;
387 case LOG_DROP
: return M_DEBUG
;
388 case LOG_DUMP
: return M_DEBUG
;
389 case LOG_ERROR
: return M_ERR
;
390 case LOG_PEER_ADDRS
: return M_DEBUG
;
391 default: return M_ERR
;
395 static void vslog(struct site
*st
, uint32_t event
, cstring_t msg
, va_list ap
)
397 static void vslog(struct site
*st
, uint32_t event
, cstring_t msg
, va_list ap
)
401 class=event_log_priority(st
, event
);
403 slilog_part(st
->log
,class,"%s: ",st
->tunname
);
404 vslilog_part(st
->log
,class,msg
,ap
);
405 slilog_part(st
->log
,class,"\n");
409 static void slog(struct site
*st
, uint32_t event
, cstring_t msg
, ...)
411 static void slog(struct site
*st
, uint32_t event
, cstring_t msg
, ...)
415 vslog(st
,event
,msg
,ap
);
419 static void logtimeout(struct site
*st
, const char *fmt
, ...)
421 static void logtimeout(struct site
*st
, const char *fmt
, ...)
423 uint32_t class=event_log_priority(st
,LOG_SETUP_TIMEOUT
);
430 slilog_part(st
->log
,class,"%s: ",st
->tunname
);
431 vslilog_part(st
->log
,class,fmt
,ap
);
435 for (i
=0, delim
=" (tried ";
436 i
<st
->setup_peers
.npeers
;
438 transport_peer
*peer
=&st
->setup_peers
.peers
[i
];
439 const char *s
=comm_addr_to_string(&peer
->addr
);
440 slilog_part(st
->log
,class,"%s%s",delim
,s
);
443 slilog_part(st
->log
,class,")\n");
447 static void set_link_quality(struct site
*st
);
448 static void delete_keys(struct site
*st
, cstring_t reason
, uint32_t loglevel
);
449 static void delete_one_key(struct site
*st
, struct data_key
*key
,
450 const char *reason
/* may be 0 meaning don't log*/,
451 const char *which
/* ignored if !reasonn */,
452 uint32_t loglevel
/* ignored if !reasonn */);
453 static bool_t
initiate_key_setup(struct site
*st
, cstring_t reason
,
454 const struct comm_addr
*prod_hint
);
455 static void enter_state_run(struct site
*st
);
456 static bool_t
enter_state_resolve(struct site
*st
);
457 static void decrement_resolving_count(struct site
*st
, int by
);
458 static bool_t
enter_new_state(struct site
*st
,uint32_t next
);
459 static void enter_state_wait(struct site
*st
);
460 static void activate_new_key(struct site
*st
);
462 static bool_t
is_transform_valid(struct transform_inst_if
*transform
)
464 return transform
&& transform
->valid(transform
->st
);
467 static bool_t
current_valid(struct site
*st
)
469 return is_transform_valid(st
->current
.transform
);
472 #define DEFINE_CALL_TRANSFORM(fwdrev) \
473 static transform_apply_return \
474 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"; \
481 return transform_apply_err; \
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 int32_t wait_timeout(struct site
*st
) {
539 return st
->wait_timeout_mean
;
542 static _Bool
set_new_transform(struct site
*st
, char *pk
)
546 /* Make room for the shared key */
547 st
->sharedsecretlen
=st
->chosen_transform
->keylen?
:st
->dh
->ceil_len
;
548 assert(st
->sharedsecretlen
);
549 if (st
->sharedsecretlen
> st
->sharedsecretallocd
) {
550 st
->sharedsecretallocd
=st
->sharedsecretlen
;
551 st
->sharedsecret
=safe_realloc_ary(st
->sharedsecret
,1,
552 st
->sharedsecretallocd
,
553 "site:sharedsecret");
556 /* Generate the shared key */
557 st
->dh
->makeshared(st
->dh
->st
,st
->dhsecret
,st
->dh
->len
,pk
,
558 st
->sharedsecret
,st
->sharedsecretlen
);
560 /* Set up the transform */
561 struct transform_if
*generator
=st
->chosen_transform
;
562 struct transform_inst_if
*generated
=generator
->create(generator
->st
);
563 ok
= generated
->setkey(generated
->st
,st
->sharedsecret
,
564 st
->sharedsecretlen
,st
->our_name_later
);
566 dispose_transform(&st
->new_transform
);
567 if (!ok
) return False
;
568 st
->new_transform
=generated
;
570 slog(st
,LOG_SETUP_INIT
,"key exchange negotiated transform"
571 " %d (capabilities ours=%#"PRIx32
" theirs=%#"PRIx32
")",
572 st
->chosen_transform
->capab_transformnum
,
573 st
->local_capabilities
, st
->remote_capabilities
);
578 int32_t lenpos
, afternul
;
580 static void append_string_xinfo_start(struct buffer_if
*buf
,
581 struct xinfoadd
*xia
,
583 /* Helps construct one of the names with additional info as found
584 * in MSG1..4. Call this function first, then append all the
585 * desired extra info (not including the nul byte) to the buffer,
586 * then call append_string_xinfo_done. */
588 xia
->lenpos
= buf
->size
;
589 buf_append_string(buf
,str
);
590 buf_append_uint8(buf
,0);
591 xia
->afternul
= buf
->size
;
593 static void append_string_xinfo_done(struct buffer_if
*buf
,
594 struct xinfoadd
*xia
)
596 /* we just need to adjust the string length */
597 if (buf
->size
== xia
->afternul
) {
598 /* no extra info, strip the nul too */
599 buf_unappend_uint8(buf
);
601 put_uint16(buf
->start
+xia
->lenpos
, buf
->size
-(xia
->lenpos
+2));
605 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
606 out using a transform of config data supplied by netlink */
607 static bool_t
generate_msg(struct site
*st
, uint32_t type
, cstring_t what
)
613 st
->retries
=st
->setup_retries
;
614 BUF_ALLOC(&st
->buffer
,what
);
615 buffer_init(&st
->buffer
,0);
616 buf_append_uint32(&st
->buffer
,
617 (type
==LABEL_MSG1?
0:st
->setup_session_id
));
618 buf_append_uint32(&st
->buffer
,st
->index
);
619 buf_append_uint32(&st
->buffer
,type
);
622 append_string_xinfo_start(&st
->buffer
,&xia
,st
->localname
);
623 if ((st
->local_capabilities
& CAPAB_EARLY
) || (type
!= LABEL_MSG1
)) {
624 buf_append_uint32(&st
->buffer
,st
->local_capabilities
);
626 if (type_is_msg34(type
)) {
627 buf_append_uint16(&st
->buffer
,st
->mtu_target
);
629 append_string_xinfo_done(&st
->buffer
,&xia
);
631 buf_append_string(&st
->buffer
,st
->remotename
);
632 BUF_ADD_OBJ(append
,&st
->buffer
,st
->localN
);
633 if (type
==LABEL_MSG1
) return True
;
634 BUF_ADD_OBJ(append
,&st
->buffer
,st
->remoteN
);
635 if (type
==LABEL_MSG2
) return True
;
637 if (hacky_par_mid_failnow()) return False
;
639 if (type
==LABEL_MSG3BIS
)
640 buf_append_uint8(&st
->buffer
,st
->chosen_transform
->capab_transformnum
);
642 dhpub
=st
->dh
->makepublic(st
->dh
->st
,st
->dhsecret
,st
->dh
->len
);
643 buf_append_string(&st
->buffer
,dhpub
);
645 hash
=safe_malloc(st
->hash
->len
, "generate_msg");
646 hst
=st
->hash
->init();
647 st
->hash
->update(hst
,st
->buffer
.start
,st
->buffer
.size
);
648 st
->hash
->final(hst
,hash
);
649 sig
=st
->privkey
->sign(st
->privkey
->st
,hash
,st
->hash
->len
);
650 buf_append_string(&st
->buffer
,sig
);
656 static bool_t
unpick_name(struct buffer_if
*msg
, struct parsedname
*nm
)
659 nm
->len
=buf_unprepend_uint16(msg
);
660 CHECK_AVAIL(msg
,nm
->len
);
661 nm
->name
=buf_unprepend(msg
,nm
->len
);
662 uint8_t *nul
=memchr(nm
->name
,0,nm
->len
);
664 buffer_readonly_view(&nm
->extrainfo
,0,0);
666 buffer_readonly_view(&nm
->extrainfo
, nul
+1, msg
->start
-(nul
+1));
667 nm
->len
=nul
-nm
->name
;
672 static bool_t
unpick_msg(struct site
*st
, uint32_t type
,
673 struct buffer_if
*msg
, struct msg
*m
)
675 m
->capab_transformnum
=-1;
676 m
->hashstart
=msg
->start
;
678 m
->dest
=buf_unprepend_uint32(msg
);
680 m
->source
=buf_unprepend_uint32(msg
);
681 CHECK_TYPE(msg
,type
);
682 if (!unpick_name(msg
,&m
->remote
)) return False
;
683 m
->remote_capabilities
=0;
685 if (m
->remote
.extrainfo
.size
) {
686 CHECK_AVAIL(&m
->remote
.extrainfo
,4);
687 m
->remote_capabilities
=buf_unprepend_uint32(&m
->remote
.extrainfo
);
689 if (type_is_msg34(type
) && m
->remote
.extrainfo
.size
) {
690 CHECK_AVAIL(&m
->remote
.extrainfo
,2);
691 m
->remote_mtu
=buf_unprepend_uint16(&m
->remote
.extrainfo
);
693 if (!unpick_name(msg
,&m
->local
)) return False
;
694 if (type
==LABEL_PROD
) {
698 CHECK_AVAIL(msg
,NONCELEN
);
699 m
->nR
=buf_unprepend(msg
,NONCELEN
);
700 if (type
==LABEL_MSG1
) {
704 CHECK_AVAIL(msg
,NONCELEN
);
705 m
->nL
=buf_unprepend(msg
,NONCELEN
);
706 if (type
==LABEL_MSG2
) {
710 if (type
==LABEL_MSG3BIS
) {
712 m
->capab_transformnum
= buf_unprepend_uint8(msg
);
714 m
->capab_transformnum
= CAPAB_TRANSFORMNUM_ANCIENT
;
717 m
->pklen
=buf_unprepend_uint16(msg
);
718 CHECK_AVAIL(msg
,m
->pklen
);
719 m
->pk
=buf_unprepend(msg
,m
->pklen
);
720 m
->hashlen
=msg
->start
-m
->hashstart
;
722 m
->siglen
=buf_unprepend_uint16(msg
);
723 CHECK_AVAIL(msg
,m
->siglen
);
724 m
->sig
=buf_unprepend(msg
,m
->siglen
);
727 /* In `process_msg3_msg4' below, we assume that we can write a nul
728 * terminator following the signature. Make sure there's enough space.
730 if (msg
->start
>= msg
->base
+ msg
->alloclen
)
736 static bool_t
name_matches(const struct parsedname
*nm
, const char *expected
)
738 int expected_len
=strlen(expected
);
740 nm
->len
== expected_len
&&
741 !memcmp(nm
->name
, expected
, expected_len
);
744 static bool_t
check_msg(struct site
*st
, uint32_t type
, struct msg
*m
,
747 if (type
==LABEL_MSG1
) return True
;
749 /* Check that the site names and our nonce have been sent
750 back correctly, and then store our peer's nonce. */
751 if (!name_matches(&m
->remote
,st
->remotename
)) {
752 *error
="wrong remote site name";
755 if (!name_matches(&m
->local
,st
->localname
)) {
756 *error
="wrong local site name";
759 if (memcmp(m
->nL
,st
->localN
,NONCELEN
)!=0) {
760 *error
="wrong locally-generated nonce";
763 if (type
==LABEL_MSG2
) return True
;
764 if (!consttime_memeq(m
->nR
,st
->remoteN
,NONCELEN
)!=0) {
765 *error
="wrong remotely-generated nonce";
768 /* MSG3 has complicated rules about capabilities, which are
769 * handled in process_msg3. */
770 if (type
==LABEL_MSG3
|| type
==LABEL_MSG3BIS
) return True
;
771 if (m
->remote_capabilities
!=st
->remote_capabilities
) {
772 *error
="remote capabilities changed";
775 if (type
==LABEL_MSG4
) return True
;
776 *error
="unknown message type";
780 static bool_t
generate_msg1(struct site
*st
)
782 st
->random
->generate(st
->random
->st
,NONCELEN
,st
->localN
);
783 return generate_msg(st
,LABEL_MSG1
,"site:MSG1");
786 static bool_t
process_msg1(struct site
*st
, struct buffer_if
*msg1
,
787 const struct comm_addr
*src
, struct msg
*m
)
789 /* We've already determined we're in an appropriate state to
790 process an incoming MSG1, and that the MSG1 has correct values
793 st
->setup_session_id
=m
->source
;
794 st
->remote_capabilities
=m
->remote_capabilities
;
795 memcpy(st
->remoteN
,m
->nR
,NONCELEN
);
799 static bool_t
generate_msg2(struct site
*st
)
801 st
->random
->generate(st
->random
->st
,NONCELEN
,st
->localN
);
802 return generate_msg(st
,LABEL_MSG2
,"site:MSG2");
805 static bool_t
process_msg2(struct site
*st
, struct buffer_if
*msg2
,
806 const struct comm_addr
*src
)
811 if (!unpick_msg(st
,LABEL_MSG2
,msg2
,&m
)) return False
;
812 if (!check_msg(st
,LABEL_MSG2
,&m
,&err
)) {
813 slog(st
,LOG_SEC
,"msg2: %s",err
);
816 st
->setup_session_id
=m
.source
;
817 st
->remote_capabilities
=m
.remote_capabilities
;
819 /* Select the transform to use */
821 uint32_t remote_transforms
= st
->remote_capabilities
& CAPAB_TRANSFORM_MASK
;
822 if (!remote_transforms
)
823 /* old secnets only had this one transform */
824 remote_transforms
= 1UL << CAPAB_TRANSFORMNUM_ANCIENT
;
826 struct transform_if
*ti
;
828 for (i
=0; i
<st
->ntransforms
; i
++) {
829 ti
=st
->transforms
[i
];
830 if ((1UL << ti
->capab_transformnum
) & remote_transforms
)
831 goto transform_found
;
833 slog(st
,LOG_ERROR
,"no transforms in common"
834 " (us %#"PRIx32
"; them: %#"PRIx32
")",
835 st
->local_capabilities
& CAPAB_TRANSFORM_MASK
,
839 st
->chosen_transform
=ti
;
841 memcpy(st
->remoteN
,m
.nR
,NONCELEN
);
845 static bool_t
generate_msg3(struct site
*st
)
847 /* Now we have our nonce and their nonce. Think of a secret key,
848 and create message number 3. */
849 st
->random
->generate(st
->random
->st
,st
->dh
->len
,st
->dhsecret
);
850 return generate_msg(st
,
851 (st
->remote_capabilities
& CAPAB_TRANSFORM_MASK
852 ? LABEL_MSG3BIS
: LABEL_MSG3
),
856 static bool_t
process_msg3_msg4(struct site
*st
, struct msg
*m
)
861 /* Check signature and store g^x mod m */
862 hash
=safe_malloc(st
->hash
->len
, "process_msg3_msg4");
863 hst
=st
->hash
->init();
864 st
->hash
->update(hst
,m
->hashstart
,m
->hashlen
);
865 st
->hash
->final(hst
,hash
);
866 /* Terminate signature with a '0' - already checked that this will fit */
868 if (!st
->pubkey
->check(st
->pubkey
->st
,hash
,st
->hash
->len
,m
->sig
)) {
869 slog(st
,LOG_SEC
,"msg3/msg4 signature failed check!");
875 st
->remote_adv_mtu
=m
->remote_mtu
;
880 static bool_t
process_msg3(struct site
*st
, struct buffer_if
*msg3
,
881 const struct comm_addr
*src
, uint32_t msgtype
)
886 assert(msgtype
==LABEL_MSG3
|| msgtype
==LABEL_MSG3BIS
);
888 if (!unpick_msg(st
,msgtype
,msg3
,&m
)) return False
;
889 if (!check_msg(st
,msgtype
,&m
,&err
)) {
890 slog(st
,LOG_SEC
,"msg3: %s",err
);
893 uint32_t capab_adv_late
= m
.remote_capabilities
894 & ~st
->remote_capabilities
& CAPAB_EARLY
;
895 if (capab_adv_late
) {
896 slog(st
,LOG_SEC
,"msg3 impermissibly adds early capability flag(s)"
897 " %#"PRIx32
" (was %#"PRIx32
", now %#"PRIx32
")",
898 capab_adv_late
, st
->remote_capabilities
, m
.remote_capabilities
);
901 st
->remote_capabilities
|=m
.remote_capabilities
;
903 struct transform_if
*ti
;
905 for (i
=0; i
<st
->ntransforms
; i
++) {
906 ti
=st
->transforms
[i
];
907 if (ti
->capab_transformnum
== m
.capab_transformnum
)
908 goto transform_found
;
910 slog(st
,LOG_SEC
,"peer chose unknown-to-us transform %d!",
911 m
.capab_transformnum
);
914 st
->chosen_transform
=ti
;
916 if (!process_msg3_msg4(st
,&m
))
919 /* Terminate their DH public key with a '0' */
921 /* Invent our DH secret key */
922 st
->random
->generate(st
->random
->st
,st
->dh
->len
,st
->dhsecret
);
924 /* Generate the shared key and set up the transform */
925 if (!set_new_transform(st
,m
.pk
)) return False
;
930 static bool_t
generate_msg4(struct site
*st
)
932 /* We have both nonces, their public key and our private key. Generate
933 our public key, sign it and send it to them. */
934 return generate_msg(st
,LABEL_MSG4
,"site:MSG4");
937 static bool_t
process_msg4(struct site
*st
, struct buffer_if
*msg4
,
938 const struct comm_addr
*src
)
943 if (!unpick_msg(st
,LABEL_MSG4
,msg4
,&m
)) return False
;
944 if (!check_msg(st
,LABEL_MSG4
,&m
,&err
)) {
945 slog(st
,LOG_SEC
,"msg4: %s",err
);
949 if (!process_msg3_msg4(st
,&m
))
952 /* Terminate their DH public key with a '0' */
955 /* Generate the shared key and set up the transform */
956 if (!set_new_transform(st
,m
.pk
)) return False
;
967 static bool_t
unpick_msg0(struct site
*st
, struct buffer_if
*msg0
,
971 m
->dest
=buf_unprepend_uint32(msg0
);
973 m
->source
=buf_unprepend_uint32(msg0
);
975 m
->type
=buf_unprepend_uint32(msg0
);
977 /* Leaves transformed part of buffer untouched */
980 static bool_t
generate_msg5(struct site
*st
)
982 cstring_t transform_err
;
984 BUF_ALLOC(&st
->buffer
,"site:MSG5");
985 /* We are going to add four words to the message */
986 buffer_init(&st
->buffer
,calculate_max_start_pad());
987 /* Give the netlink code an opportunity to put its own stuff in the
988 message (configuration information, etc.) */
989 buf_prepend_uint32(&st
->buffer
,LABEL_MSG5
);
990 if (call_transform_forwards(st
,st
->new_transform
,
991 &st
->buffer
,&transform_err
))
993 buf_prepend_uint32(&st
->buffer
,LABEL_MSG5
);
994 buf_prepend_uint32(&st
->buffer
,st
->index
);
995 buf_prepend_uint32(&st
->buffer
,st
->setup_session_id
);
997 st
->retries
=st
->setup_retries
;
1001 static bool_t
process_msg5(struct site
*st
, struct buffer_if
*msg5
,
1002 const struct comm_addr
*src
,
1003 struct transform_inst_if
*transform
)
1006 cstring_t transform_err
;
1008 if (!unpick_msg0(st
,msg5
,&m
)) return False
;
1010 if (call_transform_reverse(st
,transform
,msg5
,&transform_err
)) {
1011 /* There's a problem */
1012 slog(st
,LOG_SEC
,"process_msg5: transform: %s",transform_err
);
1015 /* Buffer should now contain untransformed PING packet data */
1016 CHECK_AVAIL(msg5
,4);
1017 if (buf_unprepend_uint32(msg5
)!=LABEL_MSG5
) {
1018 slog(st
,LOG_SEC
,"MSG5/PING packet contained wrong label");
1021 /* Older versions of secnet used to write some config data here
1022 * which we ignore. So we don't CHECK_EMPTY */
1026 static void create_msg6(struct site
*st
, struct transform_inst_if
*transform
,
1027 uint32_t session_id
)
1029 cstring_t transform_err
;
1031 BUF_ALLOC(&st
->buffer
,"site:MSG6");
1032 /* We are going to add four words to the message */
1033 buffer_init(&st
->buffer
,calculate_max_start_pad());
1034 /* Give the netlink code an opportunity to put its own stuff in the
1035 message (configuration information, etc.) */
1036 buf_prepend_uint32(&st
->buffer
,LABEL_MSG6
);
1037 transform_apply_return problem
=
1038 call_transform_forwards(st
,transform
,
1039 &st
->buffer
,&transform_err
);
1041 buf_prepend_uint32(&st
->buffer
,LABEL_MSG6
);
1042 buf_prepend_uint32(&st
->buffer
,st
->index
);
1043 buf_prepend_uint32(&st
->buffer
,session_id
);
1046 static bool_t
generate_msg6(struct site
*st
)
1048 if (!is_transform_valid(st
->new_transform
))
1050 create_msg6(st
,st
->new_transform
,st
->setup_session_id
);
1051 st
->retries
=1; /* Peer will retransmit MSG5 if this packet gets lost */
1055 static bool_t
process_msg6(struct site
*st
, struct buffer_if
*msg6
,
1056 const struct comm_addr
*src
)
1059 cstring_t transform_err
;
1061 if (!unpick_msg0(st
,msg6
,&m
)) return False
;
1063 if (call_transform_reverse(st
,st
->new_transform
,msg6
,&transform_err
)) {
1064 /* There's a problem */
1065 slog(st
,LOG_SEC
,"process_msg6: transform: %s",transform_err
);
1068 /* Buffer should now contain untransformed PING packet data */
1069 CHECK_AVAIL(msg6
,4);
1070 if (buf_unprepend_uint32(msg6
)!=LABEL_MSG6
) {
1071 slog(st
,LOG_SEC
,"MSG6/PONG packet contained invalid data");
1074 /* Older versions of secnet used to write some config data here
1075 * which we ignore. So we don't CHECK_EMPTY */
1079 static transform_apply_return
1080 decrypt_msg0(struct site
*st
, struct buffer_if
*msg0
,
1081 const struct comm_addr
*src
)
1083 cstring_t transform_err
, auxkey_err
, newkey_err
="n/a";
1085 transform_apply_return problem
;
1087 if (!unpick_msg0(st
,msg0
,&m
)) return False
;
1089 /* Keep a copy so we can try decrypting it with multiple keys */
1090 buffer_copy(&st
->scratch
, msg0
);
1092 problem
= call_transform_reverse(st
,st
->current
.transform
,
1093 msg0
,&transform_err
);
1095 if (!st
->auxiliary_is_new
)
1096 delete_one_key(st
,&st
->auxiliary_key
,
1097 "peer has used new key","auxiliary key",LOG_SEC
);
1100 if (transform_apply_return_badseq(problem
))
1103 buffer_copy(msg0
, &st
->scratch
);
1104 problem
= call_transform_reverse(st
,st
->auxiliary_key
.transform
,
1107 slog(st
,LOG_DROP
,"processing packet which uses auxiliary key");
1108 if (st
->auxiliary_is_new
) {
1109 /* We previously timed out in state SENTMSG5 but it turns
1110 * out that our peer did in fact get our MSG5 and is
1111 * using the new key. So we should switch to it too. */
1112 /* This is a bit like activate_new_key. */
1115 st
->current
=st
->auxiliary_key
;
1116 st
->auxiliary_key
=t
;
1118 delete_one_key(st
,&st
->auxiliary_key
,"peer has used new key",
1119 "previous key",LOG_SEC
);
1120 st
->auxiliary_is_new
=0;
1121 st
->renegotiate_key_time
=st
->auxiliary_renegotiate_key_time
;
1125 if (transform_apply_return_badseq(problem
))
1128 if (st
->state
==SITE_SENTMSG5
) {
1129 buffer_copy(msg0
, &st
->scratch
);
1130 problem
= call_transform_reverse(st
,st
->new_transform
,
1133 /* It looks like we didn't get the peer's MSG6 */
1134 /* This is like a cut-down enter_new_state(SITE_RUN) */
1135 slog(st
,LOG_STATE
,"will enter state RUN (MSG0 with new key)");
1136 BUF_FREE(&st
->buffer
);
1138 activate_new_key(st
);
1139 return 0; /* do process the data in this packet */
1141 if (transform_apply_return_badseq(problem
))
1145 slog(st
,LOG_SEC
,"transform: %s (aux: %s, new: %s)",
1146 transform_err
,auxkey_err
,newkey_err
);
1147 initiate_key_setup(st
,"incoming message would not decrypt",0);
1148 send_nak(src
,m
.dest
,m
.source
,m
.type
,msg0
,"message would not decrypt");
1153 slog(st
,LOG_DROP
,"transform: %s (bad seq.)",transform_err
);
1158 static bool_t
process_msg0(struct site
*st
, struct buffer_if
*msg0
,
1159 const struct comm_addr
*src
)
1162 transform_apply_return problem
;
1164 problem
= decrypt_msg0(st
,msg0
,src
);
1165 if (problem
==transform_apply_seqdupe
) {
1166 /* We recently received another copy of this packet, maybe due
1167 * to polypath. That's not a problem; indeed, for the
1168 * purposes of transport address management it is a success.
1169 * But we don't want to process the packet. */
1170 transport_data_msgok(st
,src
);
1176 CHECK_AVAIL(msg0
,4);
1177 type
=buf_unprepend_uint32(msg0
);
1180 /* We must forget about the current session. */
1181 delete_keys(st
,"request from peer",LOG_SEC
);
1182 /* probably, the peer is shutting down, and this is going to fail,
1183 * but we need to be trying to bring the link up again */
1185 initiate_key_setup(st
,"peer requested key teardown",0);
1188 /* Deliver to netlink layer */
1189 st
->netlink
->deliver(st
->netlink
->st
,msg0
);
1190 transport_data_msgok(st
,src
);
1191 /* See whether we should start negotiating a new key */
1192 if (st
->now
> st
->renegotiate_key_time
)
1193 initiate_key_setup(st
,"incoming packet in renegotiation window",0);
1196 slog(st
,LOG_SEC
,"incoming encrypted message of type %08x "
1203 static void dump_packet(struct site
*st
, struct buffer_if
*buf
,
1204 const struct comm_addr
*addr
, bool_t incoming
,
1207 uint32_t dest
=get_uint32(buf
->start
);
1208 uint32_t source
=get_uint32(buf
->start
+4);
1209 uint32_t msgtype
=get_uint32(buf
->start
+8);
1211 if (st
->log_events
& LOG_DUMP
)
1212 slilog(st
->log
,M_DEBUG
,"%s: %s: %08x<-%08x: %08x: %s%s",
1213 st
->tunname
,incoming?
"incoming":"outgoing",
1214 dest
,source
,msgtype
,comm_addr_to_string(addr
),
1218 static bool_t
comm_addr_sendmsg(struct site
*st
,
1219 const struct comm_addr
*dest
,
1220 struct buffer_if
*buf
)
1223 struct comm_clientinfo
*commclientinfo
= 0;
1225 for (i
=0; i
< st
->ncomms
; i
++) {
1226 if (st
->comms
[i
] == dest
->comm
) {
1227 commclientinfo
= st
->commclientinfos
[i
];
1231 return dest
->comm
->sendmsg(dest
->comm
->st
, buf
, dest
, commclientinfo
);
1234 static uint32_t site_status(void *st
)
1239 static bool_t
send_msg(struct site
*st
)
1241 if (st
->retries
>0) {
1242 transport_xmit(st
, &st
->setup_peers
, &st
->buffer
, True
);
1243 st
->timeout
=st
->now
+st
->setup_retry_interval
;
1246 } else if (st
->state
==SITE_SENTMSG5
) {
1247 logtimeout(st
,"timed out sending MSG5, stashing new key");
1248 /* We stash the key we have produced, in case it turns out that
1249 * our peer did see our MSG5 after all and starts using it. */
1250 /* This is a bit like some of activate_new_key */
1251 struct transform_inst_if
*t
;
1252 t
=st
->auxiliary_key
.transform
;
1253 st
->auxiliary_key
.transform
=st
->new_transform
;
1254 st
->new_transform
=t
;
1255 dispose_transform(&st
->new_transform
);
1257 st
->auxiliary_is_new
=1;
1258 st
->auxiliary_key
.key_timeout
=st
->now
+st
->key_lifetime
;
1259 st
->auxiliary_renegotiate_key_time
=st
->now
+st
->key_renegotiate_time
;
1260 st
->auxiliary_key
.remote_session_id
=st
->setup_session_id
;
1262 enter_state_wait(st
);
1265 logtimeout(st
,"timed out sending key setup packet "
1266 "(in state %s)",state_name(st
->state
));
1267 enter_state_wait(st
);
1272 static void site_resolve_callback(void *sst
, const struct comm_addr
*addrs
,
1273 int stored_naddrs
, int all_naddrs
,
1274 const char *address
, const char *failwhy
)
1276 struct site
*st
=sst
;
1278 if (!stored_naddrs
) {
1279 slog(st
,LOG_ERROR
,"resolution of %s failed: %s",address
,failwhy
);
1281 slog(st
,LOG_PEER_ADDRS
,"resolution of %s completed, %d addrs, eg: %s",
1282 address
, all_naddrs
, comm_addr_to_string(&addrs
[0]));;
1284 int space
=st
->transport_peers_max
-st
->resolving_n_results_stored
;
1285 int n_tocopy
=MIN(stored_naddrs
,space
);
1286 COPY_ARRAY(st
->resolving_results
+ st
->resolving_n_results_stored
,
1289 st
->resolving_n_results_stored
+= n_tocopy
;
1290 st
->resolving_n_results_all
+= all_naddrs
;
1293 decrement_resolving_count(st
,1);
1296 static void decrement_resolving_count(struct site
*st
, int by
)
1298 assert(st
->resolving_count
>0);
1299 st
->resolving_count
-=by
;
1301 if (st
->resolving_count
)
1304 /* OK, we are done with them all. Handle combined results. */
1306 const struct comm_addr
*addrs
=st
->resolving_results
;
1307 int naddrs
=st
->resolving_n_results_stored
;
1308 assert(naddrs
<=st
->transport_peers_max
);
1311 if (naddrs
!= st
->resolving_n_results_all
) {
1312 slog(st
,LOG_SETUP_INIT
,"resolution of supplied addresses/names"
1313 " yielded too many results (%d > %d), some ignored",
1314 st
->resolving_n_results_all
, naddrs
);
1316 slog(st
,LOG_STATE
,"resolution completed, %d addrs, eg: %s",
1317 naddrs
, iaddr_to_string(&addrs
[0].ia
));;
1320 switch (st
->state
) {
1322 if (transport_compute_setupinit_peers(st
,addrs
,naddrs
,0)) {
1323 enter_new_state(st
,SITE_SENTMSG1
);
1325 /* Can't figure out who to try to to talk to */
1326 slog(st
,LOG_SETUP_INIT
,
1327 "key exchange failed: cannot find peer address");
1328 enter_state_run(st
);
1331 case SITE_SENTMSG1
: case SITE_SENTMSG2
:
1332 case SITE_SENTMSG3
: case SITE_SENTMSG4
:
1335 /* We start using the address immediately for data too.
1336 * It's best to store it in st->peers now because we might
1337 * go via SENTMSG5, WAIT, and a MSG0, straight into using
1338 * the new key (without updating the data peer addrs). */
1339 transport_resolve_complete(st
,addrs
,naddrs
);
1340 } else if (st
->local_mobile
) {
1341 /* We can't let this rest because we may have a peer
1342 * address which will break in the future. */
1343 slog(st
,LOG_SETUP_INIT
,"resolution failed: "
1344 "abandoning key exchange");
1345 enter_state_wait(st
);
1347 slog(st
,LOG_SETUP_INIT
,"resolution failed: "
1348 " continuing to use source address of peer's packets"
1349 " for key exchange and ultimately data");
1354 slog(st
,LOG_SETUP_INIT
,"resolution completed tardily,"
1355 " updating peer address(es)");
1356 transport_resolve_complete_tardy(st
,addrs
,naddrs
);
1357 } else if (st
->local_mobile
) {
1358 /* Not very good. We should queue (another) renegotiation
1359 * so that we can update the peer address. */
1360 st
->key_renegotiate_time
=st
->now
+wait_timeout(st
);
1362 slog(st
,LOG_SETUP_INIT
,"resolution failed: "
1363 " continuing to use source address of peer's packets");
1373 static bool_t
initiate_key_setup(struct site
*st
, cstring_t reason
,
1374 const struct comm_addr
*prod_hint
)
1376 /* Reentrancy hazard: can call enter_new_state/enter_state_* */
1377 if (st
->state
!=SITE_RUN
) return False
;
1378 slog(st
,LOG_SETUP_INIT
,"initiating key exchange (%s)",reason
);
1379 if (st
->addresses
) {
1380 slog(st
,LOG_SETUP_INIT
,"resolving peer address(es)");
1381 return enter_state_resolve(st
);
1382 } else if (transport_compute_setupinit_peers(st
,0,0,prod_hint
)) {
1383 return enter_new_state(st
,SITE_SENTMSG1
);
1385 slog(st
,LOG_SETUP_INIT
,"key exchange failed: no address for peer");
1389 static void activate_new_key(struct site
*st
)
1391 struct transform_inst_if
*t
;
1393 /* We have three transform instances, which we swap between old,
1395 t
=st
->auxiliary_key
.transform
;
1396 st
->auxiliary_key
.transform
=st
->current
.transform
;
1397 st
->current
.transform
=st
->new_transform
;
1398 st
->new_transform
=t
;
1399 dispose_transform(&st
->new_transform
);
1402 st
->auxiliary_is_new
=0;
1403 st
->auxiliary_key
.key_timeout
=st
->current
.key_timeout
;
1404 st
->current
.key_timeout
=st
->now
+st
->key_lifetime
;
1405 st
->renegotiate_key_time
=st
->now
+st
->key_renegotiate_time
;
1406 transport_peers_copy(st
,&st
->peers
,&st
->setup_peers
);
1407 st
->current
.remote_session_id
=st
->setup_session_id
;
1409 /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
1410 * But their mtu be unspecified, in which case we just use ours. */
1411 uint32_t intersite_mtu
=
1412 MIN(st
->mtu_target
, st
->remote_adv_mtu ?
: ~(uint32_t)0);
1413 st
->netlink
->set_mtu(st
->netlink
->st
,intersite_mtu
);
1415 slog(st
,LOG_ACTIVATE_KEY
,"new key activated"
1416 " (mtu ours=%"PRId32
" theirs=%"PRId32
" intersite=%"PRId32
")",
1417 st
->mtu_target
, st
->remote_adv_mtu
, intersite_mtu
);
1418 enter_state_run(st
);
1421 static void delete_one_key(struct site
*st
, struct data_key
*key
,
1422 cstring_t reason
, cstring_t which
, uint32_t loglevel
)
1424 if (!is_transform_valid(key
->transform
)) return;
1425 if (reason
) slog(st
,loglevel
,"%s deleted (%s)",which
,reason
);
1426 dispose_transform(&key
->transform
);
1430 static void delete_keys(struct site
*st
, cstring_t reason
, uint32_t loglevel
)
1432 if (current_valid(st
)) {
1433 slog(st
,loglevel
,"session closed (%s)",reason
);
1435 delete_one_key(st
,&st
->current
,0,0,0);
1436 set_link_quality(st
);
1438 delete_one_key(st
,&st
->auxiliary_key
,0,0,0);
1441 static void state_assert(struct site
*st
, bool_t ok
)
1443 if (!ok
) fatal("site:state_assert");
1446 static void enter_state_stop(struct site
*st
)
1448 st
->state
=SITE_STOP
;
1450 delete_keys(st
,"entering state STOP",LOG_TIMEOUT_KEY
);
1451 dispose_transform(&st
->new_transform
);
1454 static void set_link_quality(struct site
*st
)
1457 if (current_valid(st
))
1458 quality
=LINK_QUALITY_UP
;
1459 else if (st
->state
==SITE_WAIT
|| st
->state
==SITE_STOP
)
1460 quality
=LINK_QUALITY_DOWN
;
1461 else if (st
->addresses
)
1462 quality
=LINK_QUALITY_DOWN_CURRENT_ADDRESS
;
1463 else if (transport_peers_valid(&st
->peers
))
1464 quality
=LINK_QUALITY_DOWN_STALE_ADDRESS
;
1466 quality
=LINK_QUALITY_DOWN
;
1468 st
->netlink
->set_quality(st
->netlink
->st
,quality
);
1471 static void enter_state_run(struct site
*st
)
1473 slog(st
,LOG_STATE
,"entering state RUN");
1477 st
->setup_session_id
=0;
1478 transport_peers_clear(st
,&st
->setup_peers
);
1479 FILLZERO(st
->localN
);
1480 FILLZERO(st
->remoteN
);
1481 dispose_transform(&st
->new_transform
);
1482 memset(st
->dhsecret
,0,st
->dh
->len
);
1483 if (st
->sharedsecret
) memset(st
->sharedsecret
,0,st
->sharedsecretlen
);
1484 set_link_quality(st
);
1486 if (st
->keepalive
&& !current_valid(st
))
1487 initiate_key_setup(st
, "keepalive", 0);
1490 static bool_t
ensure_resolving(struct site
*st
)
1492 /* Reentrancy hazard: may call site_resolve_callback and hence
1493 * enter_new_state, enter_state_* and generate_msg*. */
1494 if (st
->resolving_count
)
1497 assert(st
->addresses
);
1499 /* resolver->request might reentrantly call site_resolve_callback
1500 * which will decrement st->resolving, so we need to increment it
1501 * twice beforehand to prevent decrement from thinking we're
1502 * finished, and decrement it ourselves. Alternatively if
1503 * everything fails then there are no callbacks due and we simply
1504 * set it to 0 and return false.. */
1505 st
->resolving_n_results_stored
=0;
1506 st
->resolving_n_results_all
=0;
1507 st
->resolving_count
+=2;
1508 const char **addrp
=st
->addresses
;
1509 const char *address
;
1511 for (; (address
=*addrp
++); ) {
1512 bool_t ok
= st
->resolver
->request(st
->resolver
->st
,address
,
1513 st
->remoteport
,st
->comms
[0],
1514 site_resolve_callback
,st
);
1516 st
->resolving_count
++;
1520 st
->resolving_count
=0;
1523 decrement_resolving_count(st
,2);
1527 static bool_t
enter_state_resolve(struct site
*st
)
1529 /* Reentrancy hazard! See ensure_resolving. */
1530 state_assert(st
,st
->state
==SITE_RUN
);
1531 slog(st
,LOG_STATE
,"entering state RESOLVE");
1532 st
->state
=SITE_RESOLVE
;
1533 return ensure_resolving(st
);
1536 static bool_t
enter_new_state(struct site
*st
, uint32_t next
)
1538 bool_t (*gen
)(struct site
*st
);
1541 slog(st
,LOG_STATE
,"entering state %s",state_name(next
));
1544 state_assert(st
,st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
);
1546 st
->msg1_crossed_logged
= False
;
1549 state_assert(st
,st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
||
1550 st
->state
==SITE_SENTMSG1
|| st
->state
==SITE_WAIT
);
1554 state_assert(st
,st
->state
==SITE_SENTMSG1
);
1555 BUF_FREE(&st
->buffer
);
1559 state_assert(st
,st
->state
==SITE_SENTMSG2
);
1560 BUF_FREE(&st
->buffer
);
1564 state_assert(st
,st
->state
==SITE_SENTMSG3
);
1565 BUF_FREE(&st
->buffer
);
1569 state_assert(st
,st
->state
==SITE_SENTMSG4
);
1570 BUF_FREE(&st
->buffer
);
1575 fatal("enter_new_state(%s): invalid new state",state_name(next
));
1579 if (hacky_par_start_failnow()) return False
;
1581 r
= gen(st
) && send_msg(st
);
1584 st
->setup_retries
, st
->setup_retry_interval
,
1589 if (next
==SITE_RUN
) {
1590 BUF_FREE(&st
->buffer
); /* Never reused */
1591 st
->timeout
=0; /* Never retransmit */
1592 activate_new_key(st
);
1596 slog(st
,LOG_ERROR
,"error entering state %s",state_name(next
));
1597 st
->buffer
.free
=False
; /* Unconditionally use the buffer; it may be
1598 in either state, and enter_state_wait() will
1600 enter_state_wait(st
);
1604 /* msg7 tells our peer that we're about to forget our key */
1605 static bool_t
send_msg7(struct site
*st
, cstring_t reason
)
1607 cstring_t transform_err
;
1609 if (current_valid(st
) && st
->buffer
.free
1610 && transport_peers_valid(&st
->peers
)) {
1611 BUF_ALLOC(&st
->buffer
,"site:MSG7");
1612 buffer_init(&st
->buffer
,calculate_max_start_pad());
1613 buf_append_uint32(&st
->buffer
,LABEL_MSG7
);
1614 buf_append_string(&st
->buffer
,reason
);
1615 if (call_transform_forwards(st
, st
->current
.transform
,
1616 &st
->buffer
, &transform_err
))
1618 buf_prepend_uint32(&st
->buffer
,LABEL_MSG0
);
1619 buf_prepend_uint32(&st
->buffer
,st
->index
);
1620 buf_prepend_uint32(&st
->buffer
,st
->current
.remote_session_id
);
1621 transport_xmit(st
,&st
->peers
,&st
->buffer
,True
);
1622 BUF_FREE(&st
->buffer
);
1629 /* We go into this state if our peer becomes uncommunicative. Similar to
1630 the "stop" state, we forget all session keys for a while, before
1631 re-entering the "run" state. */
1632 static void enter_state_wait(struct site
*st
)
1634 slog(st
,LOG_STATE
,"entering state WAIT");
1635 st
->timeout
=st
->now
+wait_timeout(st
);
1636 st
->state
=SITE_WAIT
;
1637 set_link_quality(st
);
1638 BUF_FREE(&st
->buffer
); /* will have had an outgoing packet in it */
1639 /* XXX Erase keys etc. */
1642 static void generate_prod(struct site
*st
, struct buffer_if
*buf
)
1645 buf_append_uint32(buf
,0);
1646 buf_append_uint32(buf
,0);
1647 buf_append_uint32(buf
,LABEL_PROD
);
1648 buf_append_string(buf
,st
->localname
);
1649 buf_append_string(buf
,st
->remotename
);
1652 static void generate_send_prod(struct site
*st
,
1653 const struct comm_addr
*source
)
1655 if (!st
->allow_send_prod
) return; /* too soon */
1656 if (!(st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
||
1657 st
->state
==SITE_WAIT
)) return; /* we'd ignore peer's MSG1 */
1659 slog(st
,LOG_SETUP_INIT
,"prodding peer for key exchange");
1660 st
->allow_send_prod
=0;
1661 generate_prod(st
,&st
->scratch
);
1662 bool_t ok
= comm_addr_sendmsg(st
, source
, &st
->scratch
);
1663 dump_packet(st
,&st
->scratch
,source
,False
,ok
);
1666 static inline void site_settimeout(uint64_t timeout
, int *timeout_io
)
1669 int64_t offset
=timeout
-*now
;
1670 if (offset
<0) offset
=0;
1671 if (offset
>INT_MAX
) offset
=INT_MAX
;
1672 if (*timeout_io
<0 || offset
<*timeout_io
)
1677 static int site_beforepoll(void *sst
, struct pollfd
*fds
, int *nfds_io
,
1680 struct site
*st
=sst
;
1682 BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
1685 /* Work out when our next timeout is. The earlier of 'timeout' or
1686 'current.key_timeout'. A stored value of '0' indicates no timeout
1688 site_settimeout(st
->timeout
, timeout_io
);
1689 site_settimeout(st
->current
.key_timeout
, timeout_io
);
1690 site_settimeout(st
->auxiliary_key
.key_timeout
, timeout_io
);
1692 return 0; /* success */
1695 static void check_expiry(struct site
*st
, struct data_key
*key
,
1698 if (key
->key_timeout
&& *now
>key
->key_timeout
) {
1699 delete_one_key(st
,key
,"maximum life exceeded",which
,LOG_TIMEOUT_KEY
);
1703 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1704 static void site_afterpoll(void *sst
, struct pollfd
*fds
, int nfds
)
1706 struct site
*st
=sst
;
1709 if (st
->timeout
&& *now
>st
->timeout
) {
1711 if (st
->state
>=SITE_SENTMSG1
&& st
->state
<=SITE_SENTMSG5
) {
1712 if (!hacky_par_start_failnow())
1714 } else if (st
->state
==SITE_WAIT
) {
1715 enter_state_run(st
);
1717 slog(st
,LOG_ERROR
,"site_afterpoll: unexpected timeout, state=%d",
1721 check_expiry(st
,&st
->current
,"current key");
1722 check_expiry(st
,&st
->auxiliary_key
,"auxiliary key");
1725 /* This function is called by the netlink device to deliver packets
1726 intended for the remote network. The packet is in "raw" wire
1727 format, but is guaranteed to be word-aligned. */
1728 static void site_outgoing(void *sst
, struct buffer_if
*buf
)
1730 struct site
*st
=sst
;
1731 cstring_t transform_err
;
1733 if (st
->state
==SITE_STOP
) {
1738 st
->allow_send_prod
=1;
1740 /* In all other states we consider delivering the packet if we have
1741 a valid key and a valid address to send it to. */
1742 if (current_valid(st
) && transport_peers_valid(&st
->peers
)) {
1743 /* Transform it and send it */
1745 buf_prepend_uint32(buf
,LABEL_MSG9
);
1746 if (call_transform_forwards(st
, st
->current
.transform
,
1747 buf
, &transform_err
))
1749 buf_prepend_uint32(buf
,LABEL_MSG0
);
1750 buf_prepend_uint32(buf
,st
->index
);
1751 buf_prepend_uint32(buf
,st
->current
.remote_session_id
);
1752 transport_xmit(st
,&st
->peers
,buf
,False
);
1759 slog(st
,LOG_DROP
,"discarding outgoing packet of size %d",buf
->size
);
1761 initiate_key_setup(st
,"outgoing packet",0);
1764 static bool_t
named_for_us(struct site
*st
, const struct buffer_if
*buf_in
,
1765 uint32_t type
, struct msg
*m
)
1766 /* For packets which are identified by the local and remote names.
1767 * If it has our name and our peer's name in it it's for us. */
1769 struct buffer_if buf
[1];
1770 buffer_readonly_clone(buf
,buf_in
);
1771 return unpick_msg(st
,type
,buf
,m
)
1772 && name_matches(&m
->remote
,st
->remotename
)
1773 && name_matches(&m
->local
,st
->localname
);
1776 static bool_t
we_have_priority(struct site
*st
, const struct msg
*m
) {
1777 if ((st
->local_capabilities
& m
->remote_capabilities
)
1778 && CAPAB_PRIORITY_MOBILE
) {
1779 if (st
->local_mobile
) return True
;
1780 if (st
-> peer_mobile
) return False
;
1782 return st
->our_name_later
;
1785 static bool_t
setup_late_msg_ok(struct site
*st
,
1786 const struct buffer_if
*buf_in
,
1788 const struct comm_addr
*source
) {
1789 /* For setup packets which seem from their type like they are
1790 * late. Maybe they came via a different path. All we do is make
1791 * a note of the sending address, iff they look like they are part
1792 * of the current key setup attempt. */
1794 if (!named_for_us(st
,buf_in
,msgtype
,&m
))
1795 /* named_for_us calls unpick_msg which gets the nonces */
1797 if (!consttime_memeq(m
.nR
,st
->remoteN
,NONCELEN
) ||
1798 !consttime_memeq(m
.nL
,st
->localN
, NONCELEN
))
1799 /* spoof ? from stale run ? who knows */
1801 transport_setup_msgok(st
,source
);
1805 /* This function is called by the communication device to deliver
1806 packets from our peers.
1807 It should return True if the packet is recognised as being for
1808 this current site instance (and should therefore not be processed
1809 by other sites), even if the packet was otherwise ignored. */
1810 static bool_t
site_incoming(void *sst
, struct buffer_if
*buf
,
1811 const struct comm_addr
*source
)
1813 struct site
*st
=sst
;
1815 if (buf
->size
< 12) return False
;
1817 uint32_t dest
=get_uint32(buf
->start
);
1818 uint32_t msgtype
=get_uint32(buf
->start
+8);
1819 struct msg named_msg
;
1821 if (msgtype
==LABEL_MSG1
) {
1822 if (!named_for_us(st
,buf
,msgtype
,&named_msg
))
1824 /* It's a MSG1 addressed to us. Decide what to do about it. */
1825 dump_packet(st
,buf
,source
,True
,True
);
1826 if (st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
||
1827 st
->state
==SITE_WAIT
) {
1828 /* We should definitely process it */
1829 transport_compute_setupinit_peers(st
,0,0,source
);
1830 if (process_msg1(st
,buf
,source
,&named_msg
)) {
1831 slog(st
,LOG_SETUP_INIT
,"key setup initiated by peer");
1832 bool_t entered
=enter_new_state(st
,SITE_SENTMSG2
);
1833 if (entered
&& st
->addresses
&& st
->local_mobile
)
1834 /* We must do this as the very last thing, because
1835 the resolver callback might reenter us. */
1836 ensure_resolving(st
);
1838 slog(st
,LOG_ERROR
,"failed to process incoming msg1");
1842 } else if (st
->state
==SITE_SENTMSG1
) {
1843 /* We've just sent a message 1! They may have crossed on
1844 the wire. If we have priority then we ignore the
1845 incoming one, otherwise we process it as usual. */
1846 if (we_have_priority(st
,&named_msg
)) {
1848 if (!st
->msg1_crossed_logged
++)
1849 slog(st
,LOG_SETUP_INIT
,"crossed msg1s; we are higher "
1850 "priority => ignore incoming msg1");
1853 slog(st
,LOG_SETUP_INIT
,"crossed msg1s; we are lower "
1854 "priority => use incoming msg1");
1855 if (process_msg1(st
,buf
,source
,&named_msg
)) {
1856 BUF_FREE(&st
->buffer
); /* Free our old message 1 */
1857 transport_setup_msgok(st
,source
);
1858 enter_new_state(st
,SITE_SENTMSG2
);
1860 slog(st
,LOG_ERROR
,"failed to process an incoming "
1861 "crossed msg1 (we have low priority)");
1866 } else if (st
->state
==SITE_SENTMSG2
||
1867 st
->state
==SITE_SENTMSG4
) {
1868 if (consttime_memeq(named_msg
.nR
,st
->remoteN
,NONCELEN
)) {
1869 /* We are ahead in the protocol, but that msg1 had the
1870 * peer's nonce so presumably it is from this key
1871 * exchange run, via a slower route */
1872 transport_setup_msgok(st
,source
);
1874 slog(st
,LOG_UNEXPECTED
,"competing incoming message 1");
1879 /* The message 1 was received at an unexpected stage of the
1880 key setup. Well, they lost the race. */
1881 slog(st
,LOG_UNEXPECTED
,"unexpected incoming message 1");
1885 if (msgtype
==LABEL_PROD
) {
1886 if (!named_for_us(st
,buf
,msgtype
,&named_msg
))
1888 dump_packet(st
,buf
,source
,True
,True
);
1889 if (st
->state
!=SITE_RUN
) {
1890 slog(st
,LOG_DROP
,"ignoring PROD when not in state RUN");
1891 } else if (current_valid(st
)) {
1892 slog(st
,LOG_DROP
,"ignoring PROD when we think we have a key");
1894 initiate_key_setup(st
,"peer sent PROD packet",source
);
1899 if (dest
==st
->index
) {
1900 /* Explicitly addressed to us */
1901 if (msgtype
!=LABEL_MSG0
) dump_packet(st
,buf
,source
,True
,True
);
1904 /* If the source is our current peer then initiate a key setup,
1905 because our peer's forgotten the key */
1906 if (get_uint32(buf
->start
+4)==st
->current
.remote_session_id
) {
1908 initiated
= initiate_key_setup(st
,"received a NAK",source
);
1909 if (!initiated
) generate_send_prod(st
,source
);
1911 slog(st
,LOG_SEC
,"bad incoming NAK");
1915 process_msg0(st
,buf
,source
);
1918 /* Setup packet: should not have been explicitly addressed
1920 slog(st
,LOG_SEC
,"incoming explicitly addressed msg1");
1923 /* Setup packet: expected only in state SENTMSG1 */
1924 if (st
->state
!=SITE_SENTMSG1
) {
1925 if ((st
->state
==SITE_SENTMSG3
||
1926 st
->state
==SITE_SENTMSG5
) &&
1927 setup_late_msg_ok(st
,buf
,msgtype
,source
))
1929 slog(st
,LOG_UNEXPECTED
,"unexpected MSG2");
1930 } else if (process_msg2(st
,buf
,source
)) {
1931 transport_setup_msgok(st
,source
);
1932 enter_new_state(st
,SITE_SENTMSG3
);
1934 slog(st
,LOG_SEC
,"invalid MSG2");
1939 /* Setup packet: expected only in state SENTMSG2 */
1940 if (st
->state
!=SITE_SENTMSG2
) {
1941 if ((st
->state
==SITE_SENTMSG4
) &&
1942 setup_late_msg_ok(st
,buf
,msgtype
,source
))
1944 slog(st
,LOG_UNEXPECTED
,"unexpected MSG3");
1945 } else if (process_msg3(st
,buf
,source
,msgtype
)) {
1946 transport_setup_msgok(st
,source
);
1947 enter_new_state(st
,SITE_SENTMSG4
);
1949 slog(st
,LOG_SEC
,"invalid MSG3");
1953 /* Setup packet: expected only in state SENTMSG3 */
1954 if (st
->state
!=SITE_SENTMSG3
) {
1955 if ((st
->state
==SITE_SENTMSG5
) &&
1956 setup_late_msg_ok(st
,buf
,msgtype
,source
))
1958 slog(st
,LOG_UNEXPECTED
,"unexpected MSG4");
1959 } else if (process_msg4(st
,buf
,source
)) {
1960 transport_setup_msgok(st
,source
);
1961 enter_new_state(st
,SITE_SENTMSG5
);
1963 slog(st
,LOG_SEC
,"invalid MSG4");
1967 /* Setup packet: expected only in state SENTMSG4 */
1968 /* (may turn up in state RUN if our return MSG6 was lost
1969 and the new key has already been activated. In that
1970 case we discard it. The peer will realise that we
1971 are using the new key when they see our data packets.
1972 Until then the peer's data packets to us get discarded. */
1973 if (st
->state
==SITE_SENTMSG4
) {
1974 if (process_msg5(st
,buf
,source
,st
->new_transform
)) {
1975 transport_setup_msgok(st
,source
);
1976 enter_new_state(st
,SITE_RUN
);
1978 slog(st
,LOG_SEC
,"invalid MSG5");
1980 } else if (st
->state
==SITE_RUN
) {
1981 if (process_msg5(st
,buf
,source
,st
->current
.transform
)) {
1982 slog(st
,LOG_DROP
,"got MSG5, retransmitting MSG6");
1983 transport_setup_msgok(st
,source
);
1984 create_msg6(st
,st
->current
.transform
,
1985 st
->current
.remote_session_id
);
1986 transport_xmit(st
,&st
->peers
,&st
->buffer
,True
);
1987 BUF_FREE(&st
->buffer
);
1989 slog(st
,LOG_SEC
,"invalid MSG5 (in state RUN)");
1992 slog(st
,LOG_UNEXPECTED
,"unexpected MSG5");
1996 /* Setup packet: expected only in state SENTMSG5 */
1997 if (st
->state
!=SITE_SENTMSG5
) {
1998 slog(st
,LOG_UNEXPECTED
,"unexpected MSG6");
1999 } else if (process_msg6(st
,buf
,source
)) {
2000 BUF_FREE(&st
->buffer
); /* Free message 5 */
2001 transport_setup_msgok(st
,source
);
2002 activate_new_key(st
);
2004 slog(st
,LOG_SEC
,"invalid MSG6");
2008 slog(st
,LOG_SEC
,"received message of unknown type 0x%08x",
2019 static void site_control(void *vst
, bool_t run
)
2021 struct site
*st
=vst
;
2022 if (run
) enter_state_run(st
);
2023 else enter_state_stop(st
);
2026 static void site_phase_hook(void *sst
, uint32_t newphase
)
2028 struct site
*st
=sst
;
2030 /* The program is shutting down; tell our peer */
2031 send_msg7(st
,"shutting down");
2034 static void site_childpersist_clearkeys(void *sst
, uint32_t newphase
)
2036 struct site
*st
=sst
;
2037 dispose_transform(&st
->current
.transform
);
2038 dispose_transform(&st
->auxiliary_key
.transform
);
2039 dispose_transform(&st
->new_transform
);
2040 /* Not much point overwiting the signing key, since we loaded it
2041 from disk, and it is only valid prospectively if at all,
2043 /* XXX it would be best to overwrite the DH state, because that
2044 _is_ relevant to forward secrecy. However we have no
2045 convenient interface for doing that and in practice gmp has
2046 probably dribbled droppings all over the malloc arena. A good
2047 way to fix this would be to have a privsep child for asymmetric
2048 crypto operations, but that's a task for another day. */
2051 static list_t
*site_apply(closure_t
*self
, struct cloc loc
, dict_t
*context
,
2054 static uint32_t index_sequence
;
2062 st
->cl
.description
="site";
2063 st
->cl
.type
=CL_SITE
;
2065 st
->cl
.interface
=&st
->ops
;
2067 st
->ops
.control
=site_control
;
2068 st
->ops
.status
=site_status
;
2070 /* First parameter must be a dict */
2071 item
=list_elem(args
,0);
2072 if (!item
|| item
->type
!=t_dict
)
2073 cfgfatal(loc
,"site","parameter must be a dictionary\n");
2075 dict
=item
->data
.dict
;
2076 st
->localname
=dict_read_string(dict
, "local-name", True
, "site", loc
);
2077 st
->remotename
=dict_read_string(dict
, "name", True
, "site", loc
);
2079 st
->keepalive
=dict_read_bool(dict
,"keepalive",False
,"site",loc
,False
);
2081 st
->peer_mobile
=dict_read_bool(dict
,"mobile",False
,"site",loc
,False
);
2083 dict_read_bool(dict
,"local-mobile",False
,"site",loc
,False
);
2085 /* Sanity check (which also allows the 'sites' file to include
2086 site() closures for all sites including our own): refuse to
2087 talk to ourselves */
2088 if (strcmp(st
->localname
,st
->remotename
)==0) {
2089 Message(M_DEBUG
,"site %s: local-name==name -> ignoring this site\n",
2091 if (st
->peer_mobile
!= st
->local_mobile
)
2092 cfgfatal(loc
,"site","site %s's peer-mobile=%d"
2093 " but our local-mobile=%d\n",
2094 st
->localname
, st
->peer_mobile
, st
->local_mobile
);
2098 if (st
->peer_mobile
&& st
->local_mobile
) {
2099 Message(M_WARNING
,"site %s: site is mobile but so are we"
2100 " -> ignoring this site\n", st
->remotename
);
2105 assert(index_sequence
< 0xffffffffUL
);
2106 st
->index
= ++index_sequence
;
2107 st
->local_capabilities
= 0;
2108 st
->netlink
=find_cl_if(dict
,"link",CL_NETLINK
,True
,"site",loc
);
2110 #define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
2111 list_t *things##_cfg=dict_lookup(dict,dictkey); \
2112 if (!things##_cfg) \
2113 cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
2114 st->nthings=list_length(things##_cfg); \
2115 NEW_ARY(st->things,st->nthings); \
2116 assert(st->nthings); \
2117 for (i=0; i<st->nthings; i++) { \
2118 item_t *item=list_elem(things##_cfg,i); \
2119 if (item->type!=t_closure) \
2120 cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
2121 closure_t *cl=item->data.closure; \
2122 if (cl->type!=CL_TYPE) \
2123 cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
2124 st->things[i]=cl->interface; \
2128 GET_CLOSURE_LIST("comm",comms
,ncomms
,CL_COMM
);
2130 NEW_ARY(st
->commclientinfos
, st
->ncomms
);
2131 dict_t
*comminfo
= dict_read_dict(dict
,"comm-info",False
,"site",loc
);
2132 for (i
=0; i
<st
->ncomms
; i
++) {
2133 st
->commclientinfos
[i
] =
2135 st
->comms
[i
]->clientinfo(st
->comms
[i
],comminfo
,loc
);
2138 st
->resolver
=find_cl_if(dict
,"resolver",CL_RESOLVER
,True
,"site",loc
);
2139 st
->log
=find_cl_if(dict
,"log",CL_LOG
,True
,"site",loc
);
2140 st
->random
=find_cl_if(dict
,"random",CL_RANDOMSRC
,True
,"site",loc
);
2142 st
->privkey
=find_cl_if(dict
,"local-key",CL_RSAPRIVKEY
,True
,"site",loc
);
2143 st
->addresses
=dict_read_string_array(dict
,"address",False
,"site",loc
,0);
2145 st
->remoteport
=dict_read_number(dict
,"port",True
,"site",loc
,0);
2146 else st
->remoteport
=0;
2147 st
->pubkey
=find_cl_if(dict
,"key",CL_RSAPUBKEY
,True
,"site",loc
);
2149 GET_CLOSURE_LIST("transform",transforms
,ntransforms
,CL_TRANSFORM
);
2151 st
->dh
=find_cl_if(dict
,"dh",CL_DH
,True
,"site",loc
);
2152 st
->hash
=find_cl_if(dict
,"hash",CL_HASH
,True
,"site",loc
);
2154 #define DEFAULT(D) (st->peer_mobile || st->local_mobile \
2155 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
2156 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
2158 st
->key_lifetime
= CFG_NUMBER("key-lifetime", KEY_LIFETIME
);
2159 st
->setup_retries
= CFG_NUMBER("setup-retries", SETUP_RETRIES
);
2160 st
->setup_retry_interval
= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL
);
2161 st
->wait_timeout_mean
= CFG_NUMBER("wait-time", WAIT_TIME
);
2162 st
->mtu_target
= dict_read_number(dict
,"mtu-target",False
,"site",loc
,0);
2164 st
->mobile_peer_expiry
= dict_read_number(
2165 dict
,"mobile-peer-expiry",False
,"site",loc
,DEFAULT_MOBILE_PEER_EXPIRY
);
2167 const char *peerskey
= st
->peer_mobile
2168 ?
"mobile-peers-max" : "static-peers-max";
2169 st
->transport_peers_max
= dict_read_number(
2170 dict
,peerskey
,False
,"site",loc
, st
->addresses ?
4 : 3);
2171 if (st
->transport_peers_max
<1 ||
2172 st
->transport_peers_max
>MAX_PEER_ADDRS
) {
2173 cfgfatal(loc
,"site", "%s must be in range 1.."
2174 STRING(MAX_PEER_ADDRS
) "\n", peerskey
);
2177 if (st
->key_lifetime
< DEFAULT(KEY_RENEGOTIATE_GAP
)*2)
2178 st
->key_renegotiate_time
=st
->key_lifetime
/2;
2180 st
->key_renegotiate_time
=st
->key_lifetime
-DEFAULT(KEY_RENEGOTIATE_GAP
);
2181 st
->key_renegotiate_time
=dict_read_number(
2182 dict
,"renegotiate-time",False
,"site",loc
,st
->key_renegotiate_time
);
2183 if (st
->key_renegotiate_time
> st
->key_lifetime
) {
2184 cfgfatal(loc
,"site",
2185 "renegotiate-time must be less than key-lifetime\n");
2188 st
->log_events
=string_list_to_word(dict_lookup(dict
,"log-events"),
2189 log_event_table
,"site");
2191 st
->resolving_count
=0;
2192 st
->allow_send_prod
=0;
2194 st
->tunname
=safe_malloc(strlen(st
->localname
)+strlen(st
->remotename
)+5,
2196 sprintf(st
->tunname
,"%s<->%s",st
->localname
,st
->remotename
);
2198 /* The information we expect to see in incoming messages of type 1 */
2199 /* fixme: lots of unchecked overflows here, but the results are only
2200 corrupted packets rather than undefined behaviour */
2201 st
->our_name_later
=(strcmp(st
->localname
,st
->remotename
)>0);
2203 buffer_new(&st
->buffer
,SETUP_BUFFER_LEN
);
2205 buffer_new(&st
->scratch
,SETUP_BUFFER_LEN
);
2206 BUF_ALLOC(&st
->scratch
,"site:scratch");
2208 /* We are interested in poll(), but only for timeouts. We don't have
2209 any fds of our own. */
2210 register_for_poll(st
, site_beforepoll
, site_afterpoll
, "site");
2213 st
->remote_capabilities
=0;
2214 st
->chosen_transform
=0;
2215 st
->current
.key_timeout
=0;
2216 st
->auxiliary_key
.key_timeout
=0;
2217 transport_peers_clear(st
,&st
->peers
);
2218 transport_peers_clear(st
,&st
->setup_peers
);
2219 /* XXX mlock these */
2220 st
->dhsecret
=safe_malloc(st
->dh
->len
,"site:dhsecret");
2221 st
->sharedsecretlen
=st
->sharedsecretallocd
=0;
2224 for (i
=0; i
<st
->ntransforms
; i
++) {
2225 struct transform_if
*ti
=st
->transforms
[i
];
2226 uint32_t capbit
= 1UL << ti
->capab_transformnum
;
2227 if (st
->local_capabilities
& capbit
)
2228 slog(st
,LOG_ERROR
,"transformnum capability bit"
2229 " %d (%#"PRIx32
") reused", ti
->capab_transformnum
, capbit
);
2230 st
->local_capabilities
|= capbit
;
2233 if (st
->local_mobile
|| st
->peer_mobile
)
2234 st
->local_capabilities
|= CAPAB_PRIORITY_MOBILE
;
2236 /* We need to register the remote networks with the netlink device */
2237 uint32_t netlink_mtu
; /* local virtual interface mtu */
2238 st
->netlink
->reg(st
->netlink
->st
, site_outgoing
, st
, &netlink_mtu
);
2239 if (!st
->mtu_target
)
2240 st
->mtu_target
=netlink_mtu
;
2242 for (i
=0; i
<st
->ncomms
; i
++)
2243 st
->comms
[i
]->request_notify(st
->comms
[i
]->st
, st
, site_incoming
);
2245 st
->current
.transform
=0;
2246 st
->auxiliary_key
.transform
=0;
2247 st
->new_transform
=0;
2248 st
->auxiliary_is_new
=0;
2250 enter_state_stop(st
);
2252 add_hook(PHASE_SHUTDOWN
,site_phase_hook
,st
);
2253 add_hook(PHASE_CHILDPERSIST
,site_childpersist_clearkeys
,st
);
2255 return new_closure(&st
->cl
);
2258 void site_module(dict_t
*dict
)
2260 add_closure(dict
,"site",site_apply
);
2264 /***** TRANSPORT PEERS definitions *****/
2266 static void transport_peers_debug(struct site
*st
, transport_peers
*dst
,
2267 const char *didwhat
,
2268 int nargs
, const struct comm_addr
*args
,
2273 if (!(st
->log_events
& LOG_PEER_ADDRS
))
2274 return; /* an optimisation */
2276 slog(st
, LOG_PEER_ADDRS
, "peers (%s) %s nargs=%d => npeers=%d",
2277 (dst
==&st
->peers ?
"data" :
2278 dst
==&st
->setup_peers ?
"setup" : "UNKNOWN"),
2279 didwhat
, nargs
, dst
->npeers
);
2281 for (i
=0, argp
=(void*)args
;
2283 i
++, (argp
+=stride?stride
:sizeof(*args
))) {
2284 const struct comm_addr
*ca
=(void*)argp
;
2285 slog(st
, LOG_PEER_ADDRS
, " args: addrs[%d]=%s",
2286 i
, comm_addr_to_string(ca
));
2288 for (i
=0; i
<dst
->npeers
; i
++) {
2289 struct timeval diff
;
2290 timersub(tv_now
,&dst
->peers
[i
].last
,&diff
);
2291 const struct comm_addr
*ca
=&dst
->peers
[i
].addr
;
2292 slog(st
, LOG_PEER_ADDRS
, " peers: addrs[%d]=%s T-%ld.%06ld",
2293 i
, comm_addr_to_string(ca
),
2294 (unsigned long)diff
.tv_sec
, (unsigned long)diff
.tv_usec
);
2298 static void transport_peers_expire(struct site
*st
, transport_peers
*peers
) {
2299 /* peers must be sorted first */
2300 int previous_peers
=peers
->npeers
;
2301 struct timeval oldest
;
2302 oldest
.tv_sec
= tv_now
->tv_sec
- st
->mobile_peer_expiry
;
2303 oldest
.tv_usec
= tv_now
->tv_usec
;
2304 while (peers
->npeers
>1 &&
2305 timercmp(&peers
->peers
[peers
->npeers
-1].last
, &oldest
, <))
2307 if (peers
->npeers
!= previous_peers
)
2308 transport_peers_debug(st
,peers
,"expire", 0,0,0);
2311 static bool_t
transport_peer_record_one(struct site
*st
, transport_peers
*peers
,
2312 const struct comm_addr
*ca
,
2313 const struct timeval
*tv
) {
2314 /* returns false if output is full */
2317 if (peers
->npeers
>= st
->transport_peers_max
)
2320 for (search
=0; search
<peers
->npeers
; search
++)
2321 if (comm_addr_equal(&peers
->peers
[search
].addr
, ca
))
2324 peers
->peers
[peers
->npeers
].addr
= *ca
;
2325 peers
->peers
[peers
->npeers
].last
= *tv
;
2330 static void transport_record_peers(struct site
*st
, transport_peers
*peers
,
2331 const struct comm_addr
*addrs
, int naddrs
,
2333 /* We add addrs into peers. The new entries end up at the front
2334 * and displace entries towards the end (perhaps even off the
2335 * end). Any existing matching entries are moved up to the front.
2337 * Caller must first call transport_peers_expire. */
2340 /* avoids debug for uninteresting updates */
2342 for (i
=0; i
<peers
->npeers
; i
++) {
2343 if (comm_addr_equal(&addrs
[0], &peers
->peers
[i
].addr
)) {
2344 memmove(peers
->peers
+1, peers
->peers
,
2345 sizeof(peers
->peers
[0]) * i
);
2346 peers
->peers
[0].addr
= addrs
[0];
2347 peers
->peers
[0].last
= *tv_now
;
2353 int old_npeers
=peers
->npeers
;
2354 transport_peer old_peers
[old_npeers
];
2355 COPY_ARRAY(old_peers
,peers
->peers
,old_npeers
);
2359 for (i
=0; i
<naddrs
; i
++) {
2360 if (!transport_peer_record_one(st
,peers
, &addrs
[i
], tv_now
))
2363 for (i
=0; i
<old_npeers
; i
++) {
2364 const transport_peer
*old
=&old_peers
[i
];
2365 if (!transport_peer_record_one(st
,peers
, &old
->addr
, &old
->last
))
2369 transport_peers_debug(st
,peers
,m
, naddrs
,addrs
,0);
2372 static void transport_expire_record_peers(struct site
*st
,
2373 transport_peers
*peers
,
2374 const struct comm_addr
*addrs
,
2375 int naddrs
, const char *m
) {
2376 /* Convenience function */
2377 transport_peers_expire(st
,peers
);
2378 transport_record_peers(st
,peers
,addrs
,naddrs
,m
);
2381 static bool_t
transport_compute_setupinit_peers(struct site
*st
,
2382 const struct comm_addr
*configured_addrs
/* 0 if none or not found */,
2383 int n_configured_addrs
/* 0 if none or not found */,
2384 const struct comm_addr
*incoming_packet_addr
/* 0 if none */) {
2385 if (!n_configured_addrs
&& !incoming_packet_addr
&&
2386 !transport_peers_valid(&st
->peers
))
2389 slog(st
,LOG_SETUP_INIT
,
2390 "using: %d configured addr(s);%s %d old peer addrs(es)",
2392 incoming_packet_addr ?
" incoming packet address;" : "",
2395 /* Non-mobile peers try addresses until one is plausible. The
2396 * effect is that this code always tries first the configured
2397 * address if supplied, or otherwise the address of the incoming
2398 * PROD, or finally the existing data peer if one exists; this is
2401 transport_peers_copy(st
,&st
->setup_peers
,&st
->peers
);
2402 transport_peers_expire(st
,&st
->setup_peers
);
2404 if (incoming_packet_addr
)
2405 transport_record_peers(st
,&st
->setup_peers
,
2406 incoming_packet_addr
,1, "incoming");
2408 if (n_configured_addrs
)
2409 transport_record_peers(st
,&st
->setup_peers
,
2410 configured_addrs
,n_configured_addrs
, "setupinit");
2412 assert(transport_peers_valid(&st
->setup_peers
));
2416 static void transport_setup_msgok(struct site
*st
, const struct comm_addr
*a
) {
2417 if (st
->peer_mobile
)
2418 transport_expire_record_peers(st
,&st
->setup_peers
,a
,1,"setupmsg");
2420 static void transport_data_msgok(struct site
*st
, const struct comm_addr
*a
) {
2421 if (st
->peer_mobile
)
2422 transport_expire_record_peers(st
,&st
->peers
,a
,1,"datamsg");
2425 static int transport_peers_valid(transport_peers
*peers
) {
2426 return peers
->npeers
;
2428 static void transport_peers_clear(struct site
*st
, transport_peers
*peers
) {
2430 transport_peers_debug(st
,peers
,"clear",0,0,0);
2432 static void transport_peers_copy(struct site
*st
, transport_peers
*dst
,
2433 const transport_peers
*src
) {
2434 dst
->npeers
=src
->npeers
;
2435 COPY_ARRAY(dst
->peers
, src
->peers
, dst
->npeers
);
2436 transport_peers_debug(st
,dst
,"copy",
2437 src
->npeers
, &src
->peers
->addr
, sizeof(*src
->peers
));
2440 static void transport_resolve_complete(struct site
*st
,
2441 const struct comm_addr
*addrs
,
2443 transport_expire_record_peers(st
,&st
->peers
,addrs
,naddrs
,
2445 transport_expire_record_peers(st
,&st
->setup_peers
,addrs
,naddrs
,
2449 static void transport_resolve_complete_tardy(struct site
*st
,
2450 const struct comm_addr
*addrs
,
2452 transport_expire_record_peers(st
,&st
->peers
,addrs
,naddrs
,
2453 "resolved tardily");
2456 static void transport_peers__copy_by_mask(transport_peer
*out
, int *nout_io
,
2458 const transport_peers
*inp
) {
2459 /* out and in->peers may be the same region, or nonoverlapping */
2460 const transport_peer
*in
=inp
->peers
;
2462 for (slot
=0; slot
<inp
->npeers
; slot
++) {
2463 if (!(mask
& (1U << slot
)))
2465 if (!(out
==in
&& slot
==*nout_io
))
2466 COPY_OBJ(out
[*nout_io
], in
[slot
]);
2471 void transport_xmit(struct site
*st
, transport_peers
*peers
,
2472 struct buffer_if
*buf
, bool_t candebug
) {
2474 transport_peers_expire(st
, peers
);
2475 unsigned failed
=0; /* bitmask */
2476 assert(MAX_PEER_ADDRS
< sizeof(unsigned)*CHAR_BIT
);
2479 for (slot
=0; slot
<peers
->npeers
; slot
++) {
2480 transport_peer
*peer
=&peers
->peers
[slot
];
2481 bool_t ok
= comm_addr_sendmsg(st
, &peer
->addr
, buf
);
2483 dump_packet(st
, buf
, &peer
->addr
, False
, ok
);
2485 failed
|= 1U << slot
;
2488 if (ok
&& !st
->peer_mobile
)
2491 /* Now we need to demote/delete failing addrs: if we are mobile we
2492 * merely demote them; otherwise we delete them. */
2493 if (st
->local_mobile
) {
2494 unsigned expected
= ((1U << nfailed
)-1) << (peers
->npeers
-nfailed
);
2495 /* `expected' has all the failures at the end already */
2496 if (failed
!= expected
) {
2498 transport_peer failedpeers
[nfailed
];
2499 transport_peers__copy_by_mask(failedpeers
, &fslot
, failed
,peers
);
2500 assert(fslot
== nfailed
);
2502 transport_peers__copy_by_mask(peers
->peers
,&wslot
,~failed
,peers
);
2503 assert(wslot
+nfailed
== peers
->npeers
);
2504 COPY_ARRAY(peers
->peers
+wslot
, failedpeers
, nfailed
);
2505 transport_peers_debug(st
,peers
,"mobile failure reorder",0,0,0);
2508 if (failed
&& peers
->npeers
> 1) {
2510 transport_peers__copy_by_mask(peers
->peers
,&wslot
,~failed
,peers
);
2511 peers
->npeers
=wslot
;
2512 transport_peers_debug(st
,peers
,"non-mobile failure cleanup",0,0,0);
2517 /***** END of transport peers declarations *****/