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 early_capabilities
;
322 uint32_t local_capabilities
;
323 int32_t setup_retries
; /* How many times to send setup packets */
324 int32_t setup_retry_interval
; /* Initial timeout for setup packets */
325 int32_t wait_timeout_mean
; /* How long to wait if setup unsuccessful */
326 int32_t mobile_peer_expiry
; /* How long to remember 2ary addresses */
327 int32_t key_lifetime
; /* How long a key lasts once set up */
328 int32_t key_renegotiate_time
; /* If we see traffic (or a keepalive)
329 after this time, initiate a new
332 bool_t our_name_later
; /* our name > peer name */
335 /* runtime information */
337 uint64_t now
; /* Most recently seen time */
338 bool_t allow_send_prod
;
339 bool_t msg1_crossed_logged
;
341 int resolving_n_results_all
;
342 int resolving_n_results_stored
;
343 struct comm_addr resolving_results
[MAX_PEER_ADDRS
];
345 /* The currently established session */
346 struct data_key current
;
347 struct data_key auxiliary_key
;
348 bool_t auxiliary_is_new
;
349 uint64_t renegotiate_key_time
; /* When we can negotiate a new key */
350 uint64_t auxiliary_renegotiate_key_time
;
351 transport_peers peers
; /* Current address(es) of peer for data traffic */
353 /* The current key setup protocol exchange. We can only be
354 involved in one of these at a time. There's a potential for
355 denial of service here (the attacker keeps sending a setup
356 packet; we keep trying to continue the exchange, and have to
357 timeout before we can listen for another setup packet); perhaps
358 we should keep a list of 'bad' sources for setup packets. */
359 uint32_t remote_capabilities
;
360 uint16_t remote_adv_mtu
;
361 struct transform_if
*chosen_transform
;
362 uint32_t setup_session_id
;
363 transport_peers setup_peers
;
364 uint8_t localN
[NONCELEN
]; /* Nonces for key exchange */
365 uint8_t remoteN
[NONCELEN
];
366 struct buffer_if buffer
; /* Current outgoing key exchange packet */
367 struct buffer_if scratch
;
368 int32_t retries
; /* Number of retries remaining */
369 uint64_t timeout
; /* Timeout for current state */
371 uint8_t *sharedsecret
;
372 uint32_t sharedsecretlen
, sharedsecretallocd
;
373 struct transform_inst_if
*new_transform
; /* For key setup/verify */
376 static uint32_t event_log_priority(struct site
*st
, uint32_t event
)
378 if (!(event
&st
->log_events
))
381 case LOG_UNEXPECTED
: return M_INFO
;
382 case LOG_SETUP_INIT
: return M_INFO
;
383 case LOG_SETUP_TIMEOUT
: return M_NOTICE
;
384 case LOG_ACTIVATE_KEY
: return M_INFO
;
385 case LOG_TIMEOUT_KEY
: return M_INFO
;
386 case LOG_SEC
: return M_SECURITY
;
387 case LOG_STATE
: return M_DEBUG
;
388 case LOG_DROP
: return M_DEBUG
;
389 case LOG_DUMP
: return M_DEBUG
;
390 case LOG_ERROR
: return M_ERR
;
391 case LOG_PEER_ADDRS
: return M_DEBUG
;
392 default: return M_ERR
;
396 static void vslog(struct site
*st
, uint32_t event
, cstring_t msg
, va_list ap
)
398 static void vslog(struct site
*st
, uint32_t event
, cstring_t msg
, va_list ap
)
402 class=event_log_priority(st
, event
);
404 slilog_part(st
->log
,class,"%s: ",st
->tunname
);
405 vslilog_part(st
->log
,class,msg
,ap
);
406 slilog_part(st
->log
,class,"\n");
410 static void slog(struct site
*st
, uint32_t event
, cstring_t msg
, ...)
412 static void slog(struct site
*st
, uint32_t event
, cstring_t msg
, ...)
416 vslog(st
,event
,msg
,ap
);
420 static void logtimeout(struct site
*st
, const char *fmt
, ...)
422 static void logtimeout(struct site
*st
, const char *fmt
, ...)
424 uint32_t class=event_log_priority(st
,LOG_SETUP_TIMEOUT
);
431 slilog_part(st
->log
,class,"%s: ",st
->tunname
);
432 vslilog_part(st
->log
,class,fmt
,ap
);
436 for (i
=0, delim
=" (tried ";
437 i
<st
->setup_peers
.npeers
;
439 transport_peer
*peer
=&st
->setup_peers
.peers
[i
];
440 const char *s
=comm_addr_to_string(&peer
->addr
);
441 slilog_part(st
->log
,class,"%s%s",delim
,s
);
444 slilog_part(st
->log
,class,")\n");
448 static void set_link_quality(struct site
*st
);
449 static void delete_keys(struct site
*st
, cstring_t reason
, uint32_t loglevel
);
450 static void delete_one_key(struct site
*st
, struct data_key
*key
,
451 const char *reason
/* may be 0 meaning don't log*/,
452 const char *which
/* ignored if !reasonn */,
453 uint32_t loglevel
/* ignored if !reasonn */);
454 static bool_t
initiate_key_setup(struct site
*st
, cstring_t reason
,
455 const struct comm_addr
*prod_hint
);
456 static void enter_state_run(struct site
*st
);
457 static bool_t
enter_state_resolve(struct site
*st
);
458 static void decrement_resolving_count(struct site
*st
, int by
);
459 static bool_t
enter_new_state(struct site
*st
,uint32_t next
);
460 static void enter_state_wait(struct site
*st
);
461 static void activate_new_key(struct site
*st
);
463 static bool_t
is_transform_valid(struct transform_inst_if
*transform
)
465 return transform
&& transform
->valid(transform
->st
);
468 static bool_t
current_valid(struct site
*st
)
470 return is_transform_valid(st
->current
.transform
);
473 #define DEFINE_CALL_TRANSFORM(fwdrev) \
474 static transform_apply_return \
475 call_transform_##fwdrev(struct site *st, \
476 struct transform_inst_if *transform, \
477 struct buffer_if *buf, \
478 const char **errmsg) \
480 if (!is_transform_valid(transform)) { \
481 *errmsg="transform not set up"; \
482 return transform_apply_err; \
484 return transform->fwdrev(transform->st,buf,errmsg); \
487 DEFINE_CALL_TRANSFORM(forwards
)
488 DEFINE_CALL_TRANSFORM(reverse
)
490 static void dispose_transform(struct transform_inst_if
**transform_var
)
492 struct transform_inst_if
*transform
=*transform_var
;
494 transform
->delkey(transform
->st
);
495 transform
->destroy(transform
->st
);
500 #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0)
501 #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0)
502 #define CHECK_TYPE(b,t) do { uint32_t type; \
503 CHECK_AVAIL((b),4); \
504 type=buf_unprepend_uint32((b)); \
505 if (type!=(t)) return False; } while(0)
507 static _Bool
type_is_msg34(uint32_t type
)
510 type
== LABEL_MSG3
||
511 type
== LABEL_MSG3BIS
||
518 struct buffer_if extrainfo
;
525 struct parsedname remote
;
526 struct parsedname local
;
527 uint32_t remote_capabilities
;
529 int capab_transformnum
;
539 static int32_t wait_timeout(struct site
*st
) {
540 int32_t t
= st
->wait_timeout_mean
;
543 st
->random
->generate(st
->random
->st
,sizeof(factor
),&factor
);
544 t
+= (t
/ 256) * factor
;
549 static _Bool
set_new_transform(struct site
*st
, char *pk
)
553 /* Make room for the shared key */
554 st
->sharedsecretlen
=st
->chosen_transform
->keylen?
:st
->dh
->ceil_len
;
555 assert(st
->sharedsecretlen
);
556 if (st
->sharedsecretlen
> st
->sharedsecretallocd
) {
557 st
->sharedsecretallocd
=st
->sharedsecretlen
;
558 st
->sharedsecret
=safe_realloc_ary(st
->sharedsecret
,1,
559 st
->sharedsecretallocd
,
560 "site:sharedsecret");
563 /* Generate the shared key */
564 st
->dh
->makeshared(st
->dh
->st
,st
->dhsecret
,st
->dh
->len
,pk
,
565 st
->sharedsecret
,st
->sharedsecretlen
);
567 /* Set up the transform */
568 struct transform_if
*generator
=st
->chosen_transform
;
569 struct transform_inst_if
*generated
=generator
->create(generator
->st
);
570 ok
= generated
->setkey(generated
->st
,st
->sharedsecret
,
571 st
->sharedsecretlen
,st
->our_name_later
);
573 dispose_transform(&st
->new_transform
);
574 if (!ok
) return False
;
575 st
->new_transform
=generated
;
577 slog(st
,LOG_SETUP_INIT
,"key exchange negotiated transform"
578 " %d (capabilities ours=%#"PRIx32
" theirs=%#"PRIx32
")",
579 st
->chosen_transform
->capab_bit
,
580 st
->local_capabilities
, st
->remote_capabilities
);
585 int32_t lenpos
, afternul
;
587 static void append_string_xinfo_start(struct buffer_if
*buf
,
588 struct xinfoadd
*xia
,
590 /* Helps construct one of the names with additional info as found
591 * in MSG1..4. Call this function first, then append all the
592 * desired extra info (not including the nul byte) to the buffer,
593 * then call append_string_xinfo_done. */
595 xia
->lenpos
= buf
->size
;
596 buf_append_string(buf
,str
);
597 buf_append_uint8(buf
,0);
598 xia
->afternul
= buf
->size
;
600 static void append_string_xinfo_done(struct buffer_if
*buf
,
601 struct xinfoadd
*xia
)
603 /* we just need to adjust the string length */
604 if (buf
->size
== xia
->afternul
) {
605 /* no extra info, strip the nul too */
606 buf_unappend_uint8(buf
);
608 put_uint16(buf
->start
+xia
->lenpos
, buf
->size
-(xia
->lenpos
+2));
612 /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside
613 out using a transform of config data supplied by netlink */
614 static bool_t
generate_msg(struct site
*st
, uint32_t type
, cstring_t what
)
620 st
->retries
=st
->setup_retries
;
621 BUF_ALLOC(&st
->buffer
,what
);
622 buffer_init(&st
->buffer
,0);
623 buf_append_uint32(&st
->buffer
,
624 (type
==LABEL_MSG1?
0:st
->setup_session_id
));
625 buf_append_uint32(&st
->buffer
,st
->index
);
626 buf_append_uint32(&st
->buffer
,type
);
629 append_string_xinfo_start(&st
->buffer
,&xia
,st
->localname
);
630 if ((st
->local_capabilities
& st
->early_capabilities
) ||
631 (type
!= LABEL_MSG1
)) {
632 buf_append_uint32(&st
->buffer
,st
->local_capabilities
);
634 if (type_is_msg34(type
)) {
635 buf_append_uint16(&st
->buffer
,st
->mtu_target
);
637 append_string_xinfo_done(&st
->buffer
,&xia
);
639 buf_append_string(&st
->buffer
,st
->remotename
);
640 BUF_ADD_OBJ(append
,&st
->buffer
,st
->localN
);
641 if (type
==LABEL_MSG1
) return True
;
642 BUF_ADD_OBJ(append
,&st
->buffer
,st
->remoteN
);
643 if (type
==LABEL_MSG2
) return True
;
645 if (hacky_par_mid_failnow()) return False
;
647 if (type
==LABEL_MSG3BIS
)
648 buf_append_uint8(&st
->buffer
,st
->chosen_transform
->capab_bit
);
650 dhpub
=st
->dh
->makepublic(st
->dh
->st
,st
->dhsecret
,st
->dh
->len
);
651 buf_append_string(&st
->buffer
,dhpub
);
653 hash
=safe_malloc(st
->hash
->len
, "generate_msg");
654 hst
=st
->hash
->init();
655 st
->hash
->update(hst
,st
->buffer
.start
,st
->buffer
.size
);
656 st
->hash
->final(hst
,hash
);
657 sig
=st
->privkey
->sign(st
->privkey
->st
,hash
,st
->hash
->len
);
658 buf_append_string(&st
->buffer
,sig
);
664 static bool_t
unpick_name(struct buffer_if
*msg
, struct parsedname
*nm
)
667 nm
->len
=buf_unprepend_uint16(msg
);
668 CHECK_AVAIL(msg
,nm
->len
);
669 nm
->name
=buf_unprepend(msg
,nm
->len
);
670 uint8_t *nul
=memchr(nm
->name
,0,nm
->len
);
672 buffer_readonly_view(&nm
->extrainfo
,0,0);
674 buffer_readonly_view(&nm
->extrainfo
, nul
+1, msg
->start
-(nul
+1));
675 nm
->len
=nul
-nm
->name
;
680 static bool_t
unpick_msg(struct site
*st
, uint32_t type
,
681 struct buffer_if
*msg
, struct msg
*m
)
683 m
->capab_transformnum
=-1;
684 m
->hashstart
=msg
->start
;
686 m
->dest
=buf_unprepend_uint32(msg
);
688 m
->source
=buf_unprepend_uint32(msg
);
689 CHECK_TYPE(msg
,type
);
690 if (!unpick_name(msg
,&m
->remote
)) return False
;
691 m
->remote_capabilities
=0;
693 if (m
->remote
.extrainfo
.size
) {
694 CHECK_AVAIL(&m
->remote
.extrainfo
,4);
695 m
->remote_capabilities
=buf_unprepend_uint32(&m
->remote
.extrainfo
);
697 if (type_is_msg34(type
) && m
->remote
.extrainfo
.size
) {
698 CHECK_AVAIL(&m
->remote
.extrainfo
,2);
699 m
->remote_mtu
=buf_unprepend_uint16(&m
->remote
.extrainfo
);
701 if (!unpick_name(msg
,&m
->local
)) return False
;
702 if (type
==LABEL_PROD
) {
706 CHECK_AVAIL(msg
,NONCELEN
);
707 m
->nR
=buf_unprepend(msg
,NONCELEN
);
708 if (type
==LABEL_MSG1
) {
712 CHECK_AVAIL(msg
,NONCELEN
);
713 m
->nL
=buf_unprepend(msg
,NONCELEN
);
714 if (type
==LABEL_MSG2
) {
718 if (type
==LABEL_MSG3BIS
) {
720 m
->capab_transformnum
= buf_unprepend_uint8(msg
);
722 m
->capab_transformnum
= CAPAB_BIT_ANCIENTTRANSFORM
;
725 m
->pklen
=buf_unprepend_uint16(msg
);
726 CHECK_AVAIL(msg
,m
->pklen
);
727 m
->pk
=buf_unprepend(msg
,m
->pklen
);
728 m
->hashlen
=msg
->start
-m
->hashstart
;
730 m
->siglen
=buf_unprepend_uint16(msg
);
731 CHECK_AVAIL(msg
,m
->siglen
);
732 m
->sig
=buf_unprepend(msg
,m
->siglen
);
735 /* In `process_msg3_msg4' below, we assume that we can write a nul
736 * terminator following the signature. Make sure there's enough space.
738 if (msg
->start
>= msg
->base
+ msg
->alloclen
)
744 static bool_t
name_matches(const struct parsedname
*nm
, const char *expected
)
746 int expected_len
=strlen(expected
);
748 nm
->len
== expected_len
&&
749 !memcmp(nm
->name
, expected
, expected_len
);
752 static bool_t
check_msg(struct site
*st
, uint32_t type
, struct msg
*m
,
755 if (type
==LABEL_MSG1
) return True
;
757 /* Check that the site names and our nonce have been sent
758 back correctly, and then store our peer's nonce. */
759 if (!name_matches(&m
->remote
,st
->remotename
)) {
760 *error
="wrong remote site name";
763 if (!name_matches(&m
->local
,st
->localname
)) {
764 *error
="wrong local site name";
767 if (memcmp(m
->nL
,st
->localN
,NONCELEN
)!=0) {
768 *error
="wrong locally-generated nonce";
771 if (type
==LABEL_MSG2
) return True
;
772 if (!consttime_memeq(m
->nR
,st
->remoteN
,NONCELEN
)) {
773 *error
="wrong remotely-generated nonce";
776 /* MSG3 has complicated rules about capabilities, which are
777 * handled in process_msg3. */
778 if (type
==LABEL_MSG3
|| type
==LABEL_MSG3BIS
) return True
;
779 if (m
->remote_capabilities
!=st
->remote_capabilities
) {
780 *error
="remote capabilities changed";
783 if (type
==LABEL_MSG4
) return True
;
784 *error
="unknown message type";
788 static bool_t
generate_msg1(struct site
*st
)
790 st
->random
->generate(st
->random
->st
,NONCELEN
,st
->localN
);
791 return generate_msg(st
,LABEL_MSG1
,"site:MSG1");
794 static bool_t
process_msg1(struct site
*st
, struct buffer_if
*msg1
,
795 const struct comm_addr
*src
, struct msg
*m
)
797 /* We've already determined we're in an appropriate state to
798 process an incoming MSG1, and that the MSG1 has correct values
801 st
->setup_session_id
=m
->source
;
802 st
->remote_capabilities
=m
->remote_capabilities
;
803 memcpy(st
->remoteN
,m
->nR
,NONCELEN
);
807 static bool_t
generate_msg2(struct site
*st
)
809 st
->random
->generate(st
->random
->st
,NONCELEN
,st
->localN
);
810 return generate_msg(st
,LABEL_MSG2
,"site:MSG2");
813 static bool_t
process_msg2(struct site
*st
, struct buffer_if
*msg2
,
814 const struct comm_addr
*src
)
819 if (!unpick_msg(st
,LABEL_MSG2
,msg2
,&m
)) return False
;
820 if (!check_msg(st
,LABEL_MSG2
,&m
,&err
)) {
821 slog(st
,LOG_SEC
,"msg2: %s",err
);
824 st
->setup_session_id
=m
.source
;
825 st
->remote_capabilities
=m
.remote_capabilities
;
827 /* Select the transform to use */
829 uint32_t remote_crypto_caps
= st
->remote_capabilities
& CAPAB_TRANSFORM_MASK
;
830 if (!remote_crypto_caps
)
831 /* old secnets only had this one transform */
832 remote_crypto_caps
= 1UL << CAPAB_BIT_ANCIENTTRANSFORM
;
834 #define CHOOSE_CRYPTO(kind, whats) do { \
835 struct kind##_if *iface; \
836 uint32_t bit, ours = 0; \
838 for (i= 0; i < st->n##kind##s; i++) { \
839 iface=st->kind##s[i]; \
840 bit = 1UL << iface->capab_bit; \
841 if (bit & remote_crypto_caps) goto kind##_found; \
844 slog(st,LOG_ERROR,"no " whats " in common" \
845 " (us %#"PRIx32"; them: %#"PRIx32")", \
846 st->local_capabilities & ours, remote_crypto_caps); \
849 st->chosen_##kind = iface; \
852 CHOOSE_CRYPTO(transform
, "transforms");
856 memcpy(st
->remoteN
,m
.nR
,NONCELEN
);
860 static bool_t
generate_msg3(struct site
*st
)
862 /* Now we have our nonce and their nonce. Think of a secret key,
863 and create message number 3. */
864 st
->random
->generate(st
->random
->st
,st
->dh
->len
,st
->dhsecret
);
865 return generate_msg(st
,
866 (st
->remote_capabilities
& CAPAB_TRANSFORM_MASK
867 ? LABEL_MSG3BIS
: LABEL_MSG3
),
871 static bool_t
process_msg3_msg4(struct site
*st
, struct msg
*m
)
876 /* Check signature and store g^x mod m */
877 hash
=safe_malloc(st
->hash
->len
, "process_msg3_msg4");
878 hst
=st
->hash
->init();
879 st
->hash
->update(hst
,m
->hashstart
,m
->hashlen
);
880 st
->hash
->final(hst
,hash
);
881 /* Terminate signature with a '0' - already checked that this will fit */
883 if (!st
->pubkey
->check(st
->pubkey
->st
,hash
,st
->hash
->len
,m
->sig
)) {
884 slog(st
,LOG_SEC
,"msg3/msg4 signature failed check!");
890 st
->remote_adv_mtu
=m
->remote_mtu
;
895 static bool_t
process_msg3(struct site
*st
, struct buffer_if
*msg3
,
896 const struct comm_addr
*src
, uint32_t msgtype
)
901 assert(msgtype
==LABEL_MSG3
|| msgtype
==LABEL_MSG3BIS
);
903 if (!unpick_msg(st
,msgtype
,msg3
,&m
)) return False
;
904 if (!check_msg(st
,msgtype
,&m
,&err
)) {
905 slog(st
,LOG_SEC
,"msg3: %s",err
);
908 uint32_t capab_adv_late
= m
.remote_capabilities
909 & ~st
->remote_capabilities
& st
->early_capabilities
;
910 if (capab_adv_late
) {
911 slog(st
,LOG_SEC
,"msg3 impermissibly adds early capability flag(s)"
912 " %#"PRIx32
" (was %#"PRIx32
", now %#"PRIx32
")",
913 capab_adv_late
, st
->remote_capabilities
, m
.remote_capabilities
);
916 st
->remote_capabilities
|=m
.remote_capabilities
;
918 #define CHOSE_CRYPTO(kind, what) do { \
919 struct kind##_if *iface; \
921 for (i=0; i<st->n##kind##s; i++) { \
922 iface=st->kind##s[i]; \
923 if (iface->capab_bit == m.capab_##kind##num) \
926 slog(st,LOG_SEC,"peer chose unknown-to-us " what " %d!", \
927 m.capab_##kind##num); \
930 st->chosen_##kind=iface; \
933 CHOSE_CRYPTO(transform
, "transform");
937 if (!process_msg3_msg4(st
,&m
))
940 /* Terminate their DH public key with a '0' */
942 /* Invent our DH secret key */
943 st
->random
->generate(st
->random
->st
,st
->dh
->len
,st
->dhsecret
);
945 /* Generate the shared key and set up the transform */
946 if (!set_new_transform(st
,m
.pk
)) return False
;
951 static bool_t
generate_msg4(struct site
*st
)
953 /* We have both nonces, their public key and our private key. Generate
954 our public key, sign it and send it to them. */
955 return generate_msg(st
,LABEL_MSG4
,"site:MSG4");
958 static bool_t
process_msg4(struct site
*st
, struct buffer_if
*msg4
,
959 const struct comm_addr
*src
)
964 if (!unpick_msg(st
,LABEL_MSG4
,msg4
,&m
)) return False
;
965 if (!check_msg(st
,LABEL_MSG4
,&m
,&err
)) {
966 slog(st
,LOG_SEC
,"msg4: %s",err
);
970 if (!process_msg3_msg4(st
,&m
))
973 /* Terminate their DH public key with a '0' */
976 /* Generate the shared key and set up the transform */
977 if (!set_new_transform(st
,m
.pk
)) return False
;
988 static bool_t
unpick_msg0(struct site
*st
, struct buffer_if
*msg0
,
992 m
->dest
=buf_unprepend_uint32(msg0
);
994 m
->source
=buf_unprepend_uint32(msg0
);
996 m
->type
=buf_unprepend_uint32(msg0
);
998 /* Leaves transformed part of buffer untouched */
1001 static bool_t
generate_msg5(struct site
*st
)
1003 cstring_t transform_err
;
1005 BUF_ALLOC(&st
->buffer
,"site:MSG5");
1006 /* We are going to add four words to the message */
1007 buffer_init(&st
->buffer
,calculate_max_start_pad());
1008 /* Give the netlink code an opportunity to put its own stuff in the
1009 message (configuration information, etc.) */
1010 buf_prepend_uint32(&st
->buffer
,LABEL_MSG5
);
1011 if (call_transform_forwards(st
,st
->new_transform
,
1012 &st
->buffer
,&transform_err
))
1014 buf_prepend_uint32(&st
->buffer
,LABEL_MSG5
);
1015 buf_prepend_uint32(&st
->buffer
,st
->index
);
1016 buf_prepend_uint32(&st
->buffer
,st
->setup_session_id
);
1018 st
->retries
=st
->setup_retries
;
1022 static bool_t
process_msg5(struct site
*st
, struct buffer_if
*msg5
,
1023 const struct comm_addr
*src
,
1024 struct transform_inst_if
*transform
)
1027 cstring_t transform_err
;
1029 if (!unpick_msg0(st
,msg5
,&m
)) return False
;
1031 if (call_transform_reverse(st
,transform
,msg5
,&transform_err
)) {
1032 /* There's a problem */
1033 slog(st
,LOG_SEC
,"process_msg5: transform: %s",transform_err
);
1036 /* Buffer should now contain untransformed PING packet data */
1037 CHECK_AVAIL(msg5
,4);
1038 if (buf_unprepend_uint32(msg5
)!=LABEL_MSG5
) {
1039 slog(st
,LOG_SEC
,"MSG5/PING packet contained wrong label");
1042 /* Older versions of secnet used to write some config data here
1043 * which we ignore. So we don't CHECK_EMPTY */
1047 static void create_msg6(struct site
*st
, struct transform_inst_if
*transform
,
1048 uint32_t session_id
)
1050 cstring_t transform_err
;
1052 BUF_ALLOC(&st
->buffer
,"site:MSG6");
1053 /* We are going to add four words to the message */
1054 buffer_init(&st
->buffer
,calculate_max_start_pad());
1055 /* Give the netlink code an opportunity to put its own stuff in the
1056 message (configuration information, etc.) */
1057 buf_prepend_uint32(&st
->buffer
,LABEL_MSG6
);
1058 transform_apply_return problem
=
1059 call_transform_forwards(st
,transform
,
1060 &st
->buffer
,&transform_err
);
1062 buf_prepend_uint32(&st
->buffer
,LABEL_MSG6
);
1063 buf_prepend_uint32(&st
->buffer
,st
->index
);
1064 buf_prepend_uint32(&st
->buffer
,session_id
);
1067 static bool_t
generate_msg6(struct site
*st
)
1069 if (!is_transform_valid(st
->new_transform
))
1071 create_msg6(st
,st
->new_transform
,st
->setup_session_id
);
1072 st
->retries
=1; /* Peer will retransmit MSG5 if this packet gets lost */
1076 static bool_t
process_msg6(struct site
*st
, struct buffer_if
*msg6
,
1077 const struct comm_addr
*src
)
1080 cstring_t transform_err
;
1082 if (!unpick_msg0(st
,msg6
,&m
)) return False
;
1084 if (call_transform_reverse(st
,st
->new_transform
,msg6
,&transform_err
)) {
1085 /* There's a problem */
1086 slog(st
,LOG_SEC
,"process_msg6: transform: %s",transform_err
);
1089 /* Buffer should now contain untransformed PING packet data */
1090 CHECK_AVAIL(msg6
,4);
1091 if (buf_unprepend_uint32(msg6
)!=LABEL_MSG6
) {
1092 slog(st
,LOG_SEC
,"MSG6/PONG packet contained invalid data");
1095 /* Older versions of secnet used to write some config data here
1096 * which we ignore. So we don't CHECK_EMPTY */
1100 static transform_apply_return
1101 decrypt_msg0(struct site
*st
, struct buffer_if
*msg0
,
1102 const struct comm_addr
*src
)
1104 cstring_t transform_err
, auxkey_err
, newkey_err
="n/a";
1106 transform_apply_return problem
;
1108 if (!unpick_msg0(st
,msg0
,&m
)) return False
;
1110 /* Keep a copy so we can try decrypting it with multiple keys */
1111 buffer_copy(&st
->scratch
, msg0
);
1113 problem
= call_transform_reverse(st
,st
->current
.transform
,
1114 msg0
,&transform_err
);
1116 if (!st
->auxiliary_is_new
)
1117 delete_one_key(st
,&st
->auxiliary_key
,
1118 "peer has used new key","auxiliary key",LOG_SEC
);
1121 if (transform_apply_return_badseq(problem
))
1124 buffer_copy(msg0
, &st
->scratch
);
1125 problem
= call_transform_reverse(st
,st
->auxiliary_key
.transform
,
1128 slog(st
,LOG_DROP
,"processing packet which uses auxiliary key");
1129 if (st
->auxiliary_is_new
) {
1130 /* We previously timed out in state SENTMSG5 but it turns
1131 * out that our peer did in fact get our MSG5 and is
1132 * using the new key. So we should switch to it too. */
1133 /* This is a bit like activate_new_key. */
1136 st
->current
=st
->auxiliary_key
;
1137 st
->auxiliary_key
=t
;
1139 delete_one_key(st
,&st
->auxiliary_key
,"peer has used new key",
1140 "previous key",LOG_SEC
);
1141 st
->auxiliary_is_new
=0;
1142 st
->renegotiate_key_time
=st
->auxiliary_renegotiate_key_time
;
1146 if (transform_apply_return_badseq(problem
))
1149 if (st
->state
==SITE_SENTMSG5
) {
1150 buffer_copy(msg0
, &st
->scratch
);
1151 problem
= call_transform_reverse(st
,st
->new_transform
,
1154 /* It looks like we didn't get the peer's MSG6 */
1155 /* This is like a cut-down enter_new_state(SITE_RUN) */
1156 slog(st
,LOG_STATE
,"will enter state RUN (MSG0 with new key)");
1157 BUF_FREE(&st
->buffer
);
1159 activate_new_key(st
);
1160 return 0; /* do process the data in this packet */
1162 if (transform_apply_return_badseq(problem
))
1166 slog(st
,LOG_SEC
,"transform: %s (aux: %s, new: %s)",
1167 transform_err
,auxkey_err
,newkey_err
);
1168 initiate_key_setup(st
,"incoming message would not decrypt",0);
1169 send_nak(src
,m
.dest
,m
.source
,m
.type
,msg0
,"message would not decrypt");
1174 slog(st
,LOG_DROP
,"transform: %s (bad seq.)",transform_err
);
1179 static bool_t
process_msg0(struct site
*st
, struct buffer_if
*msg0
,
1180 const struct comm_addr
*src
)
1183 transform_apply_return problem
;
1185 problem
= decrypt_msg0(st
,msg0
,src
);
1186 if (problem
==transform_apply_seqdupe
) {
1187 /* We recently received another copy of this packet, maybe due
1188 * to polypath. That's not a problem; indeed, for the
1189 * purposes of transport address management it is a success.
1190 * But we don't want to process the packet. */
1191 transport_data_msgok(st
,src
);
1197 CHECK_AVAIL(msg0
,4);
1198 type
=buf_unprepend_uint32(msg0
);
1201 /* We must forget about the current session. */
1202 delete_keys(st
,"request from peer",LOG_SEC
);
1203 /* probably, the peer is shutting down, and this is going to fail,
1204 * but we need to be trying to bring the link up again */
1206 initiate_key_setup(st
,"peer requested key teardown",0);
1209 /* Deliver to netlink layer */
1210 st
->netlink
->deliver(st
->netlink
->st
,msg0
);
1211 transport_data_msgok(st
,src
);
1212 /* See whether we should start negotiating a new key */
1213 if (st
->now
> st
->renegotiate_key_time
)
1214 initiate_key_setup(st
,"incoming packet in renegotiation window",0);
1217 slog(st
,LOG_SEC
,"incoming encrypted message of type %08x "
1224 static void dump_packet(struct site
*st
, struct buffer_if
*buf
,
1225 const struct comm_addr
*addr
, bool_t incoming
,
1228 uint32_t dest
=get_uint32(buf
->start
);
1229 uint32_t source
=get_uint32(buf
->start
+4);
1230 uint32_t msgtype
=get_uint32(buf
->start
+8);
1232 if (st
->log_events
& LOG_DUMP
)
1233 slilog(st
->log
,M_DEBUG
,"%s: %s: %08x<-%08x: %08x: %s%s",
1234 st
->tunname
,incoming?
"incoming":"outgoing",
1235 dest
,source
,msgtype
,comm_addr_to_string(addr
),
1239 static bool_t
comm_addr_sendmsg(struct site
*st
,
1240 const struct comm_addr
*dest
,
1241 struct buffer_if
*buf
)
1244 struct comm_clientinfo
*commclientinfo
= 0;
1246 for (i
=0; i
< st
->ncomms
; i
++) {
1247 if (st
->comms
[i
] == dest
->comm
) {
1248 commclientinfo
= st
->commclientinfos
[i
];
1252 return dest
->comm
->sendmsg(dest
->comm
->st
, buf
, dest
, commclientinfo
);
1255 static uint32_t site_status(void *st
)
1260 static bool_t
send_msg(struct site
*st
)
1262 if (st
->retries
>0) {
1263 transport_xmit(st
, &st
->setup_peers
, &st
->buffer
, True
);
1264 st
->timeout
=st
->now
+st
->setup_retry_interval
;
1267 } else if (st
->state
==SITE_SENTMSG5
) {
1268 logtimeout(st
,"timed out sending MSG5, stashing new key");
1269 /* We stash the key we have produced, in case it turns out that
1270 * our peer did see our MSG5 after all and starts using it. */
1271 /* This is a bit like some of activate_new_key */
1272 struct transform_inst_if
*t
;
1273 t
=st
->auxiliary_key
.transform
;
1274 st
->auxiliary_key
.transform
=st
->new_transform
;
1275 st
->new_transform
=t
;
1276 dispose_transform(&st
->new_transform
);
1278 st
->auxiliary_is_new
=1;
1279 st
->auxiliary_key
.key_timeout
=st
->now
+st
->key_lifetime
;
1280 st
->auxiliary_renegotiate_key_time
=st
->now
+st
->key_renegotiate_time
;
1281 st
->auxiliary_key
.remote_session_id
=st
->setup_session_id
;
1283 enter_state_wait(st
);
1286 logtimeout(st
,"timed out sending key setup packet "
1287 "(in state %s)",state_name(st
->state
));
1288 enter_state_wait(st
);
1293 static void site_resolve_callback(void *sst
, const struct comm_addr
*addrs
,
1294 int stored_naddrs
, int all_naddrs
,
1295 const char *address
, const char *failwhy
)
1297 struct site
*st
=sst
;
1299 if (!stored_naddrs
) {
1300 slog(st
,LOG_ERROR
,"resolution of %s failed: %s",address
,failwhy
);
1302 slog(st
,LOG_PEER_ADDRS
,"resolution of %s completed, %d addrs, eg: %s",
1303 address
, all_naddrs
, comm_addr_to_string(&addrs
[0]));;
1305 int space
=st
->transport_peers_max
-st
->resolving_n_results_stored
;
1306 int n_tocopy
=MIN(stored_naddrs
,space
);
1307 COPY_ARRAY(st
->resolving_results
+ st
->resolving_n_results_stored
,
1310 st
->resolving_n_results_stored
+= n_tocopy
;
1311 st
->resolving_n_results_all
+= all_naddrs
;
1314 decrement_resolving_count(st
,1);
1317 static void decrement_resolving_count(struct site
*st
, int by
)
1319 assert(st
->resolving_count
>0);
1320 st
->resolving_count
-=by
;
1322 if (st
->resolving_count
)
1325 /* OK, we are done with them all. Handle combined results. */
1327 const struct comm_addr
*addrs
=st
->resolving_results
;
1328 int naddrs
=st
->resolving_n_results_stored
;
1329 assert(naddrs
<=st
->transport_peers_max
);
1332 if (naddrs
!= st
->resolving_n_results_all
) {
1333 slog(st
,LOG_SETUP_INIT
,"resolution of supplied addresses/names"
1334 " yielded too many results (%d > %d), some ignored",
1335 st
->resolving_n_results_all
, naddrs
);
1337 slog(st
,LOG_STATE
,"resolution completed, %d addrs, eg: %s",
1338 naddrs
, iaddr_to_string(&addrs
[0].ia
));;
1341 switch (st
->state
) {
1343 if (transport_compute_setupinit_peers(st
,addrs
,naddrs
,0)) {
1344 enter_new_state(st
,SITE_SENTMSG1
);
1346 /* Can't figure out who to try to to talk to */
1347 slog(st
,LOG_SETUP_INIT
,
1348 "key exchange failed: cannot find peer address");
1349 enter_state_run(st
);
1352 case SITE_SENTMSG1
: case SITE_SENTMSG2
:
1353 case SITE_SENTMSG3
: case SITE_SENTMSG4
:
1356 /* We start using the address immediately for data too.
1357 * It's best to store it in st->peers now because we might
1358 * go via SENTMSG5, WAIT, and a MSG0, straight into using
1359 * the new key (without updating the data peer addrs). */
1360 transport_resolve_complete(st
,addrs
,naddrs
);
1361 } else if (st
->local_mobile
) {
1362 /* We can't let this rest because we may have a peer
1363 * address which will break in the future. */
1364 slog(st
,LOG_SETUP_INIT
,"resolution failed: "
1365 "abandoning key exchange");
1366 enter_state_wait(st
);
1368 slog(st
,LOG_SETUP_INIT
,"resolution failed: "
1369 " continuing to use source address of peer's packets"
1370 " for key exchange and ultimately data");
1375 slog(st
,LOG_SETUP_INIT
,"resolution completed tardily,"
1376 " updating peer address(es)");
1377 transport_resolve_complete_tardy(st
,addrs
,naddrs
);
1378 } else if (st
->local_mobile
) {
1379 /* Not very good. We should queue (another) renegotiation
1380 * so that we can update the peer address. */
1381 st
->key_renegotiate_time
=st
->now
+wait_timeout(st
);
1383 slog(st
,LOG_SETUP_INIT
,"resolution failed: "
1384 " continuing to use source address of peer's packets");
1394 static bool_t
initiate_key_setup(struct site
*st
, cstring_t reason
,
1395 const struct comm_addr
*prod_hint
)
1397 /* Reentrancy hazard: can call enter_new_state/enter_state_* */
1398 if (st
->state
!=SITE_RUN
) return False
;
1399 slog(st
,LOG_SETUP_INIT
,"initiating key exchange (%s)",reason
);
1400 if (st
->addresses
) {
1401 slog(st
,LOG_SETUP_INIT
,"resolving peer address(es)");
1402 return enter_state_resolve(st
);
1403 } else if (transport_compute_setupinit_peers(st
,0,0,prod_hint
)) {
1404 return enter_new_state(st
,SITE_SENTMSG1
);
1406 slog(st
,LOG_SETUP_INIT
,"key exchange failed: no address for peer");
1410 static void activate_new_key(struct site
*st
)
1412 struct transform_inst_if
*t
;
1414 /* We have three transform instances, which we swap between old,
1416 t
=st
->auxiliary_key
.transform
;
1417 st
->auxiliary_key
.transform
=st
->current
.transform
;
1418 st
->current
.transform
=st
->new_transform
;
1419 st
->new_transform
=t
;
1420 dispose_transform(&st
->new_transform
);
1423 st
->auxiliary_is_new
=0;
1424 st
->auxiliary_key
.key_timeout
=st
->current
.key_timeout
;
1425 st
->current
.key_timeout
=st
->now
+st
->key_lifetime
;
1426 st
->renegotiate_key_time
=st
->now
+st
->key_renegotiate_time
;
1427 transport_peers_copy(st
,&st
->peers
,&st
->setup_peers
);
1428 st
->current
.remote_session_id
=st
->setup_session_id
;
1430 /* Compute the inter-site MTU. This is min( our_mtu, their_mtu ).
1431 * But their mtu be unspecified, in which case we just use ours. */
1432 uint32_t intersite_mtu
=
1433 MIN(st
->mtu_target
, st
->remote_adv_mtu ?
: ~(uint32_t)0);
1434 st
->netlink
->set_mtu(st
->netlink
->st
,intersite_mtu
);
1436 slog(st
,LOG_ACTIVATE_KEY
,"new key activated"
1437 " (mtu ours=%"PRId32
" theirs=%"PRId32
" intersite=%"PRId32
")",
1438 st
->mtu_target
, st
->remote_adv_mtu
, intersite_mtu
);
1439 enter_state_run(st
);
1442 static void delete_one_key(struct site
*st
, struct data_key
*key
,
1443 cstring_t reason
, cstring_t which
, uint32_t loglevel
)
1445 if (!is_transform_valid(key
->transform
)) return;
1446 if (reason
) slog(st
,loglevel
,"%s deleted (%s)",which
,reason
);
1447 dispose_transform(&key
->transform
);
1451 static void delete_keys(struct site
*st
, cstring_t reason
, uint32_t loglevel
)
1453 if (current_valid(st
)) {
1454 slog(st
,loglevel
,"session closed (%s)",reason
);
1456 delete_one_key(st
,&st
->current
,0,0,0);
1457 set_link_quality(st
);
1459 delete_one_key(st
,&st
->auxiliary_key
,0,0,0);
1462 static void state_assert(struct site
*st
, bool_t ok
)
1464 if (!ok
) fatal("site:state_assert");
1467 static void enter_state_stop(struct site
*st
)
1469 st
->state
=SITE_STOP
;
1471 delete_keys(st
,"entering state STOP",LOG_TIMEOUT_KEY
);
1472 dispose_transform(&st
->new_transform
);
1475 static void set_link_quality(struct site
*st
)
1478 if (current_valid(st
))
1479 quality
=LINK_QUALITY_UP
;
1480 else if (st
->state
==SITE_WAIT
|| st
->state
==SITE_STOP
)
1481 quality
=LINK_QUALITY_DOWN
;
1482 else if (st
->addresses
)
1483 quality
=LINK_QUALITY_DOWN_CURRENT_ADDRESS
;
1484 else if (transport_peers_valid(&st
->peers
))
1485 quality
=LINK_QUALITY_DOWN_STALE_ADDRESS
;
1487 quality
=LINK_QUALITY_DOWN
;
1489 st
->netlink
->set_quality(st
->netlink
->st
,quality
);
1492 static void enter_state_run(struct site
*st
)
1494 slog(st
,LOG_STATE
,"entering state RUN%s",
1495 current_valid(st
) ?
" (keyed)" : " (unkeyed)");
1499 st
->setup_session_id
=0;
1500 transport_peers_clear(st
,&st
->setup_peers
);
1501 FILLZERO(st
->localN
);
1502 FILLZERO(st
->remoteN
);
1503 dispose_transform(&st
->new_transform
);
1504 memset(st
->dhsecret
,0,st
->dh
->len
);
1505 if (st
->sharedsecret
) memset(st
->sharedsecret
,0,st
->sharedsecretlen
);
1506 set_link_quality(st
);
1508 if (st
->keepalive
&& !current_valid(st
))
1509 initiate_key_setup(st
, "keepalive", 0);
1512 static bool_t
ensure_resolving(struct site
*st
)
1514 /* Reentrancy hazard: may call site_resolve_callback and hence
1515 * enter_new_state, enter_state_* and generate_msg*. */
1516 if (st
->resolving_count
)
1519 assert(st
->addresses
);
1521 /* resolver->request might reentrantly call site_resolve_callback
1522 * which will decrement st->resolving, so we need to increment it
1523 * twice beforehand to prevent decrement from thinking we're
1524 * finished, and decrement it ourselves. Alternatively if
1525 * everything fails then there are no callbacks due and we simply
1526 * set it to 0 and return false.. */
1527 st
->resolving_n_results_stored
=0;
1528 st
->resolving_n_results_all
=0;
1529 st
->resolving_count
+=2;
1530 const char **addrp
=st
->addresses
;
1531 const char *address
;
1533 for (; (address
=*addrp
++); ) {
1534 bool_t ok
= st
->resolver
->request(st
->resolver
->st
,address
,
1535 st
->remoteport
,st
->comms
[0],
1536 site_resolve_callback
,st
);
1538 st
->resolving_count
++;
1542 st
->resolving_count
=0;
1545 decrement_resolving_count(st
,2);
1549 static bool_t
enter_state_resolve(struct site
*st
)
1551 /* Reentrancy hazard! See ensure_resolving. */
1552 state_assert(st
,st
->state
==SITE_RUN
);
1553 slog(st
,LOG_STATE
,"entering state RESOLVE");
1554 st
->state
=SITE_RESOLVE
;
1555 return ensure_resolving(st
);
1558 static bool_t
enter_new_state(struct site
*st
, uint32_t next
)
1560 bool_t (*gen
)(struct site
*st
);
1563 slog(st
,LOG_STATE
,"entering state %s",state_name(next
));
1566 state_assert(st
,st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
);
1568 st
->msg1_crossed_logged
= False
;
1571 state_assert(st
,st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
||
1572 st
->state
==SITE_SENTMSG1
|| st
->state
==SITE_WAIT
);
1576 state_assert(st
,st
->state
==SITE_SENTMSG1
);
1577 BUF_FREE(&st
->buffer
);
1581 state_assert(st
,st
->state
==SITE_SENTMSG2
);
1582 BUF_FREE(&st
->buffer
);
1586 state_assert(st
,st
->state
==SITE_SENTMSG3
);
1587 BUF_FREE(&st
->buffer
);
1591 state_assert(st
,st
->state
==SITE_SENTMSG4
);
1592 BUF_FREE(&st
->buffer
);
1597 fatal("enter_new_state(%s): invalid new state",state_name(next
));
1601 if (hacky_par_start_failnow()) return False
;
1603 r
= gen(st
) && send_msg(st
);
1606 st
->setup_retries
, st
->setup_retry_interval
,
1611 if (next
==SITE_RUN
) {
1612 BUF_FREE(&st
->buffer
); /* Never reused */
1613 st
->timeout
=0; /* Never retransmit */
1614 activate_new_key(st
);
1618 slog(st
,LOG_ERROR
,"error entering state %s",state_name(next
));
1619 st
->buffer
.free
=False
; /* Unconditionally use the buffer; it may be
1620 in either state, and enter_state_wait() will
1622 enter_state_wait(st
);
1626 /* msg7 tells our peer that we're about to forget our key */
1627 static bool_t
send_msg7(struct site
*st
, cstring_t reason
)
1629 cstring_t transform_err
;
1631 if (current_valid(st
) && st
->buffer
.free
1632 && transport_peers_valid(&st
->peers
)) {
1633 BUF_ALLOC(&st
->buffer
,"site:MSG7");
1634 buffer_init(&st
->buffer
,calculate_max_start_pad());
1635 buf_append_uint32(&st
->buffer
,LABEL_MSG7
);
1636 buf_append_string(&st
->buffer
,reason
);
1637 if (call_transform_forwards(st
, st
->current
.transform
,
1638 &st
->buffer
, &transform_err
))
1640 buf_prepend_uint32(&st
->buffer
,LABEL_MSG0
);
1641 buf_prepend_uint32(&st
->buffer
,st
->index
);
1642 buf_prepend_uint32(&st
->buffer
,st
->current
.remote_session_id
);
1643 transport_xmit(st
,&st
->peers
,&st
->buffer
,True
);
1644 BUF_FREE(&st
->buffer
);
1651 /* We go into this state if our peer becomes uncommunicative. Similar to
1652 the "stop" state, we forget all session keys for a while, before
1653 re-entering the "run" state. */
1654 static void enter_state_wait(struct site
*st
)
1656 slog(st
,LOG_STATE
,"entering state WAIT");
1657 st
->timeout
=st
->now
+wait_timeout(st
);
1658 st
->state
=SITE_WAIT
;
1659 set_link_quality(st
);
1660 BUF_FREE(&st
->buffer
); /* will have had an outgoing packet in it */
1661 /* XXX Erase keys etc. */
1664 static void generate_prod(struct site
*st
, struct buffer_if
*buf
)
1667 buf_append_uint32(buf
,0);
1668 buf_append_uint32(buf
,0);
1669 buf_append_uint32(buf
,LABEL_PROD
);
1670 buf_append_string(buf
,st
->localname
);
1671 buf_append_string(buf
,st
->remotename
);
1674 static void generate_send_prod(struct site
*st
,
1675 const struct comm_addr
*source
)
1677 if (!st
->allow_send_prod
) return; /* too soon */
1678 if (!(st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
||
1679 st
->state
==SITE_WAIT
)) return; /* we'd ignore peer's MSG1 */
1681 slog(st
,LOG_SETUP_INIT
,"prodding peer for key exchange");
1682 st
->allow_send_prod
=0;
1683 generate_prod(st
,&st
->scratch
);
1684 bool_t ok
= comm_addr_sendmsg(st
, source
, &st
->scratch
);
1685 dump_packet(st
,&st
->scratch
,source
,False
,ok
);
1688 static inline void site_settimeout(uint64_t timeout
, int *timeout_io
)
1691 int64_t offset
=timeout
-*now
;
1692 if (offset
<0) offset
=0;
1693 if (offset
>INT_MAX
) offset
=INT_MAX
;
1694 if (*timeout_io
<0 || offset
<*timeout_io
)
1699 static int site_beforepoll(void *sst
, struct pollfd
*fds
, int *nfds_io
,
1702 struct site
*st
=sst
;
1704 BEFOREPOLL_WANT_FDS(0); /* We don't use any file descriptors */
1707 /* Work out when our next timeout is. The earlier of 'timeout' or
1708 'current.key_timeout'. A stored value of '0' indicates no timeout
1710 site_settimeout(st
->timeout
, timeout_io
);
1711 site_settimeout(st
->current
.key_timeout
, timeout_io
);
1712 site_settimeout(st
->auxiliary_key
.key_timeout
, timeout_io
);
1714 return 0; /* success */
1717 static void check_expiry(struct site
*st
, struct data_key
*key
,
1720 if (key
->key_timeout
&& *now
>key
->key_timeout
) {
1721 delete_one_key(st
,key
,"maximum life exceeded",which
,LOG_TIMEOUT_KEY
);
1725 /* NB site_afterpoll will be called before site_beforepoll is ever called */
1726 static void site_afterpoll(void *sst
, struct pollfd
*fds
, int nfds
)
1728 struct site
*st
=sst
;
1731 if (st
->timeout
&& *now
>st
->timeout
) {
1733 if (st
->state
>=SITE_SENTMSG1
&& st
->state
<=SITE_SENTMSG5
) {
1734 if (!hacky_par_start_failnow())
1736 } else if (st
->state
==SITE_WAIT
) {
1737 enter_state_run(st
);
1739 slog(st
,LOG_ERROR
,"site_afterpoll: unexpected timeout, state=%d",
1743 check_expiry(st
,&st
->current
,"current key");
1744 check_expiry(st
,&st
->auxiliary_key
,"auxiliary key");
1747 /* This function is called by the netlink device to deliver packets
1748 intended for the remote network. The packet is in "raw" wire
1749 format, but is guaranteed to be word-aligned. */
1750 static void site_outgoing(void *sst
, struct buffer_if
*buf
)
1752 struct site
*st
=sst
;
1753 cstring_t transform_err
;
1755 if (st
->state
==SITE_STOP
) {
1760 st
->allow_send_prod
=1;
1762 /* In all other states we consider delivering the packet if we have
1763 a valid key and a valid address to send it to. */
1764 if (current_valid(st
) && transport_peers_valid(&st
->peers
)) {
1765 /* Transform it and send it */
1767 buf_prepend_uint32(buf
,LABEL_MSG9
);
1768 if (call_transform_forwards(st
, st
->current
.transform
,
1769 buf
, &transform_err
))
1771 buf_prepend_uint32(buf
,LABEL_MSG0
);
1772 buf_prepend_uint32(buf
,st
->index
);
1773 buf_prepend_uint32(buf
,st
->current
.remote_session_id
);
1774 transport_xmit(st
,&st
->peers
,buf
,False
);
1781 slog(st
,LOG_DROP
,"discarding outgoing packet of size %d",buf
->size
);
1783 initiate_key_setup(st
,"outgoing packet",0);
1786 static bool_t
named_for_us(struct site
*st
, const struct buffer_if
*buf_in
,
1787 uint32_t type
, struct msg
*m
)
1788 /* For packets which are identified by the local and remote names.
1789 * If it has our name and our peer's name in it it's for us. */
1791 struct buffer_if buf
[1];
1792 buffer_readonly_clone(buf
,buf_in
);
1793 return unpick_msg(st
,type
,buf
,m
)
1794 && name_matches(&m
->remote
,st
->remotename
)
1795 && name_matches(&m
->local
,st
->localname
);
1798 static bool_t
we_have_priority(struct site
*st
, const struct msg
*m
) {
1799 if (st
->local_capabilities
& m
->remote_capabilities
&
1800 CAPAB_PRIORITY_MOBILE
) {
1801 if (st
->local_mobile
) return True
;
1802 if (st
-> peer_mobile
) return False
;
1804 return st
->our_name_later
;
1807 static bool_t
setup_late_msg_ok(struct site
*st
,
1808 const struct buffer_if
*buf_in
,
1810 const struct comm_addr
*source
) {
1811 /* For setup packets which seem from their type like they are
1812 * late. Maybe they came via a different path. All we do is make
1813 * a note of the sending address, iff they look like they are part
1814 * of the current key setup attempt. */
1816 if (!named_for_us(st
,buf_in
,msgtype
,&m
))
1817 /* named_for_us calls unpick_msg which gets the nonces */
1819 if (!consttime_memeq(m
.nR
,st
->remoteN
,NONCELEN
) ||
1820 !consttime_memeq(m
.nL
,st
->localN
, NONCELEN
))
1821 /* spoof ? from stale run ? who knows */
1823 transport_setup_msgok(st
,source
);
1827 /* This function is called by the communication device to deliver
1828 packets from our peers.
1829 It should return True if the packet is recognised as being for
1830 this current site instance (and should therefore not be processed
1831 by other sites), even if the packet was otherwise ignored. */
1832 static bool_t
site_incoming(void *sst
, struct buffer_if
*buf
,
1833 const struct comm_addr
*source
)
1835 struct site
*st
=sst
;
1837 if (buf
->size
< 12) return False
;
1839 uint32_t dest
=get_uint32(buf
->start
);
1840 uint32_t msgtype
=get_uint32(buf
->start
+8);
1841 struct msg named_msg
;
1843 if (msgtype
==LABEL_MSG1
) {
1844 if (!named_for_us(st
,buf
,msgtype
,&named_msg
))
1846 /* It's a MSG1 addressed to us. Decide what to do about it. */
1847 dump_packet(st
,buf
,source
,True
,True
);
1848 if (st
->state
==SITE_RUN
|| st
->state
==SITE_RESOLVE
||
1849 st
->state
==SITE_WAIT
) {
1850 /* We should definitely process it */
1851 transport_compute_setupinit_peers(st
,0,0,source
);
1852 if (process_msg1(st
,buf
,source
,&named_msg
)) {
1853 slog(st
,LOG_SETUP_INIT
,"key setup initiated by peer");
1854 bool_t entered
=enter_new_state(st
,SITE_SENTMSG2
);
1855 if (entered
&& st
->addresses
&& st
->local_mobile
)
1856 /* We must do this as the very last thing, because
1857 the resolver callback might reenter us. */
1858 ensure_resolving(st
);
1860 slog(st
,LOG_ERROR
,"failed to process incoming msg1");
1864 } else if (st
->state
==SITE_SENTMSG1
) {
1865 /* We've just sent a message 1! They may have crossed on
1866 the wire. If we have priority then we ignore the
1867 incoming one, otherwise we process it as usual. */
1868 if (we_have_priority(st
,&named_msg
)) {
1870 if (!st
->msg1_crossed_logged
++)
1871 slog(st
,LOG_SETUP_INIT
,"crossed msg1s; we are higher "
1872 "priority => ignore incoming msg1");
1875 slog(st
,LOG_SETUP_INIT
,"crossed msg1s; we are lower "
1876 "priority => use incoming msg1");
1877 if (process_msg1(st
,buf
,source
,&named_msg
)) {
1878 BUF_FREE(&st
->buffer
); /* Free our old message 1 */
1879 transport_setup_msgok(st
,source
);
1880 enter_new_state(st
,SITE_SENTMSG2
);
1882 slog(st
,LOG_ERROR
,"failed to process an incoming "
1883 "crossed msg1 (we have low priority)");
1888 } else if (st
->state
==SITE_SENTMSG2
||
1889 st
->state
==SITE_SENTMSG4
) {
1890 if (consttime_memeq(named_msg
.nR
,st
->remoteN
,NONCELEN
)) {
1891 /* We are ahead in the protocol, but that msg1 had the
1892 * peer's nonce so presumably it is from this key
1893 * exchange run, via a slower route */
1894 transport_setup_msgok(st
,source
);
1896 slog(st
,LOG_UNEXPECTED
,"competing incoming message 1");
1901 /* The message 1 was received at an unexpected stage of the
1902 key setup. Well, they lost the race. */
1903 slog(st
,LOG_UNEXPECTED
,"unexpected incoming message 1");
1907 if (msgtype
==LABEL_PROD
) {
1908 if (!named_for_us(st
,buf
,msgtype
,&named_msg
))
1910 dump_packet(st
,buf
,source
,True
,True
);
1911 if (st
->state
!=SITE_RUN
) {
1912 slog(st
,LOG_DROP
,"ignoring PROD when not in state RUN");
1913 } else if (current_valid(st
)) {
1914 slog(st
,LOG_DROP
,"ignoring PROD when we think we have a key");
1916 initiate_key_setup(st
,"peer sent PROD packet",source
);
1921 if (dest
==st
->index
) {
1922 /* Explicitly addressed to us */
1923 if (msgtype
!=LABEL_MSG0
) dump_packet(st
,buf
,source
,True
,True
);
1926 /* If the source is our current peer then initiate a key setup,
1927 because our peer's forgotten the key */
1928 if (get_uint32(buf
->start
+4)==st
->current
.remote_session_id
) {
1930 initiated
= initiate_key_setup(st
,"received a NAK",source
);
1931 if (!initiated
) generate_send_prod(st
,source
);
1933 slog(st
,LOG_SEC
,"bad incoming NAK");
1937 process_msg0(st
,buf
,source
);
1940 /* Setup packet: should not have been explicitly addressed
1942 slog(st
,LOG_SEC
,"incoming explicitly addressed msg1");
1945 /* Setup packet: expected only in state SENTMSG1 */
1946 if (st
->state
!=SITE_SENTMSG1
) {
1947 if ((st
->state
==SITE_SENTMSG3
||
1948 st
->state
==SITE_SENTMSG5
) &&
1949 setup_late_msg_ok(st
,buf
,msgtype
,source
))
1951 slog(st
,LOG_UNEXPECTED
,"unexpected MSG2");
1952 } else if (process_msg2(st
,buf
,source
)) {
1953 transport_setup_msgok(st
,source
);
1954 enter_new_state(st
,SITE_SENTMSG3
);
1956 slog(st
,LOG_SEC
,"invalid MSG2");
1961 /* Setup packet: expected only in state SENTMSG2 */
1962 if (st
->state
!=SITE_SENTMSG2
) {
1963 if ((st
->state
==SITE_SENTMSG4
) &&
1964 setup_late_msg_ok(st
,buf
,msgtype
,source
))
1966 slog(st
,LOG_UNEXPECTED
,"unexpected MSG3");
1967 } else if (process_msg3(st
,buf
,source
,msgtype
)) {
1968 transport_setup_msgok(st
,source
);
1969 enter_new_state(st
,SITE_SENTMSG4
);
1971 slog(st
,LOG_SEC
,"invalid MSG3");
1975 /* Setup packet: expected only in state SENTMSG3 */
1976 if (st
->state
!=SITE_SENTMSG3
) {
1977 if ((st
->state
==SITE_SENTMSG5
) &&
1978 setup_late_msg_ok(st
,buf
,msgtype
,source
))
1980 slog(st
,LOG_UNEXPECTED
,"unexpected MSG4");
1981 } else if (process_msg4(st
,buf
,source
)) {
1982 transport_setup_msgok(st
,source
);
1983 enter_new_state(st
,SITE_SENTMSG5
);
1985 slog(st
,LOG_SEC
,"invalid MSG4");
1989 /* Setup packet: expected only in state SENTMSG4 */
1990 /* (may turn up in state RUN if our return MSG6 was lost
1991 and the new key has already been activated. In that
1992 case we discard it. The peer will realise that we
1993 are using the new key when they see our data packets.
1994 Until then the peer's data packets to us get discarded. */
1995 if (st
->state
==SITE_SENTMSG4
) {
1996 if (process_msg5(st
,buf
,source
,st
->new_transform
)) {
1997 transport_setup_msgok(st
,source
);
1998 enter_new_state(st
,SITE_RUN
);
2000 slog(st
,LOG_SEC
,"invalid MSG5");
2002 } else if (st
->state
==SITE_RUN
) {
2003 if (process_msg5(st
,buf
,source
,st
->current
.transform
)) {
2004 slog(st
,LOG_DROP
,"got MSG5, retransmitting MSG6");
2005 transport_setup_msgok(st
,source
);
2006 create_msg6(st
,st
->current
.transform
,
2007 st
->current
.remote_session_id
);
2008 transport_xmit(st
,&st
->peers
,&st
->buffer
,True
);
2009 BUF_FREE(&st
->buffer
);
2011 slog(st
,LOG_SEC
,"invalid MSG5 (in state RUN)");
2014 slog(st
,LOG_UNEXPECTED
,"unexpected MSG5");
2018 /* Setup packet: expected only in state SENTMSG5 */
2019 if (st
->state
!=SITE_SENTMSG5
) {
2020 slog(st
,LOG_UNEXPECTED
,"unexpected MSG6");
2021 } else if (process_msg6(st
,buf
,source
)) {
2022 BUF_FREE(&st
->buffer
); /* Free message 5 */
2023 transport_setup_msgok(st
,source
);
2024 activate_new_key(st
);
2026 slog(st
,LOG_SEC
,"invalid MSG6");
2030 slog(st
,LOG_SEC
,"received message of unknown type 0x%08x",
2041 static void site_control(void *vst
, bool_t run
)
2043 struct site
*st
=vst
;
2044 if (run
) enter_state_run(st
);
2045 else enter_state_stop(st
);
2048 static void site_phase_hook(void *sst
, uint32_t newphase
)
2050 struct site
*st
=sst
;
2052 /* The program is shutting down; tell our peer */
2053 send_msg7(st
,"shutting down");
2056 static void site_childpersist_clearkeys(void *sst
, uint32_t newphase
)
2058 struct site
*st
=sst
;
2059 dispose_transform(&st
->current
.transform
);
2060 dispose_transform(&st
->auxiliary_key
.transform
);
2061 dispose_transform(&st
->new_transform
);
2062 /* Not much point overwiting the signing key, since we loaded it
2063 from disk, and it is only valid prospectively if at all,
2065 /* XXX it would be best to overwrite the DH state, because that
2066 _is_ relevant to forward secrecy. However we have no
2067 convenient interface for doing that and in practice gmp has
2068 probably dribbled droppings all over the malloc arena. A good
2069 way to fix this would be to have a privsep child for asymmetric
2070 crypto operations, but that's a task for another day. */
2073 static list_t
*site_apply(closure_t
*self
, struct cloc loc
, dict_t
*context
,
2076 static uint32_t index_sequence
;
2084 st
->cl
.description
="site";
2085 st
->cl
.type
=CL_SITE
;
2087 st
->cl
.interface
=&st
->ops
;
2089 st
->ops
.control
=site_control
;
2090 st
->ops
.status
=site_status
;
2092 /* First parameter must be a dict */
2093 item
=list_elem(args
,0);
2094 if (!item
|| item
->type
!=t_dict
)
2095 cfgfatal(loc
,"site","parameter must be a dictionary\n");
2097 dict
=item
->data
.dict
;
2098 st
->localname
=dict_read_string(dict
, "local-name", True
, "site", loc
);
2099 st
->remotename
=dict_read_string(dict
, "name", True
, "site", loc
);
2101 st
->keepalive
=dict_read_bool(dict
,"keepalive",False
,"site",loc
,False
);
2103 st
->peer_mobile
=dict_read_bool(dict
,"mobile",False
,"site",loc
,False
);
2105 dict_read_bool(dict
,"local-mobile",False
,"site",loc
,False
);
2107 /* Sanity check (which also allows the 'sites' file to include
2108 site() closures for all sites including our own): refuse to
2109 talk to ourselves */
2110 if (strcmp(st
->localname
,st
->remotename
)==0) {
2111 Message(M_DEBUG
,"site %s: local-name==name -> ignoring this site\n",
2113 if (st
->peer_mobile
!= st
->local_mobile
)
2114 cfgfatal(loc
,"site","site %s's peer-mobile=%d"
2115 " but our local-mobile=%d\n",
2116 st
->localname
, st
->peer_mobile
, st
->local_mobile
);
2120 if (st
->peer_mobile
&& st
->local_mobile
) {
2121 Message(M_WARNING
,"site %s: site is mobile but so are we"
2122 " -> ignoring this site\n", st
->remotename
);
2127 assert(index_sequence
< 0xffffffffUL
);
2128 st
->index
= ++index_sequence
;
2129 st
->local_capabilities
= 0;
2130 st
->early_capabilities
= CAPAB_PRIORITY_MOBILE
;
2131 st
->netlink
=find_cl_if(dict
,"link",CL_NETLINK
,True
,"site",loc
);
2133 #define GET_CLOSURE_LIST(dictkey,things,nthings,CL_TYPE) do{ \
2134 list_t *things##_cfg=dict_lookup(dict,dictkey); \
2135 if (!things##_cfg) \
2136 cfgfatal(loc,"site","closure list \"%s\" not found\n",dictkey); \
2137 st->nthings=list_length(things##_cfg); \
2138 NEW_ARY(st->things,st->nthings); \
2139 assert(st->nthings); \
2140 for (i=0; i<st->nthings; i++) { \
2141 item_t *item=list_elem(things##_cfg,i); \
2142 if (item->type!=t_closure) \
2143 cfgfatal(loc,"site","%s is not a closure\n",dictkey); \
2144 closure_t *cl=item->data.closure; \
2145 if (cl->type!=CL_TYPE) \
2146 cfgfatal(loc,"site","%s closure wrong type\n",dictkey); \
2147 st->things[i]=cl->interface; \
2151 GET_CLOSURE_LIST("comm",comms
,ncomms
,CL_COMM
);
2153 NEW_ARY(st
->commclientinfos
, st
->ncomms
);
2154 dict_t
*comminfo
= dict_read_dict(dict
,"comm-info",False
,"site",loc
);
2155 for (i
=0; i
<st
->ncomms
; i
++) {
2156 st
->commclientinfos
[i
] =
2158 st
->comms
[i
]->clientinfo(st
->comms
[i
],comminfo
,loc
);
2161 st
->resolver
=find_cl_if(dict
,"resolver",CL_RESOLVER
,True
,"site",loc
);
2162 st
->log
=find_cl_if(dict
,"log",CL_LOG
,True
,"site",loc
);
2163 st
->random
=find_cl_if(dict
,"random",CL_RANDOMSRC
,True
,"site",loc
);
2165 st
->privkey
=find_cl_if(dict
,"local-key",CL_RSAPRIVKEY
,True
,"site",loc
);
2166 st
->addresses
=dict_read_string_array(dict
,"address",False
,"site",loc
,0);
2168 st
->remoteport
=dict_read_number(dict
,"port",True
,"site",loc
,0);
2169 else st
->remoteport
=0;
2170 st
->pubkey
=find_cl_if(dict
,"key",CL_RSAPUBKEY
,True
,"site",loc
);
2172 GET_CLOSURE_LIST("transform",transforms
,ntransforms
,CL_TRANSFORM
);
2174 st
->dh
=find_cl_if(dict
,"dh",CL_DH
,True
,"site",loc
);
2175 st
->hash
=find_cl_if(dict
,"hash",CL_HASH
,True
,"site",loc
);
2177 #define DEFAULT(D) (st->peer_mobile || st->local_mobile \
2178 ? DEFAULT_MOBILE_##D : DEFAULT_##D)
2179 #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D));
2181 st
->key_lifetime
= CFG_NUMBER("key-lifetime", KEY_LIFETIME
);
2182 st
->setup_retries
= CFG_NUMBER("setup-retries", SETUP_RETRIES
);
2183 st
->setup_retry_interval
= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL
);
2184 st
->wait_timeout_mean
= CFG_NUMBER("wait-time", WAIT_TIME
);
2185 st
->mtu_target
= dict_read_number(dict
,"mtu-target",False
,"site",loc
,0);
2187 st
->mobile_peer_expiry
= dict_read_number(
2188 dict
,"mobile-peer-expiry",False
,"site",loc
,DEFAULT_MOBILE_PEER_EXPIRY
);
2190 const char *peerskey
= st
->peer_mobile
2191 ?
"mobile-peers-max" : "static-peers-max";
2192 st
->transport_peers_max
= dict_read_number(
2193 dict
,peerskey
,False
,"site",loc
, st
->addresses ?
4 : 3);
2194 if (st
->transport_peers_max
<1 ||
2195 st
->transport_peers_max
>MAX_PEER_ADDRS
) {
2196 cfgfatal(loc
,"site", "%s must be in range 1.."
2197 STRING(MAX_PEER_ADDRS
) "\n", peerskey
);
2200 if (st
->key_lifetime
< DEFAULT(KEY_RENEGOTIATE_GAP
)*2)
2201 st
->key_renegotiate_time
=st
->key_lifetime
/2;
2203 st
->key_renegotiate_time
=st
->key_lifetime
-DEFAULT(KEY_RENEGOTIATE_GAP
);
2204 st
->key_renegotiate_time
=dict_read_number(
2205 dict
,"renegotiate-time",False
,"site",loc
,st
->key_renegotiate_time
);
2206 if (st
->key_renegotiate_time
> st
->key_lifetime
) {
2207 cfgfatal(loc
,"site",
2208 "renegotiate-time must be less than key-lifetime\n");
2211 st
->log_events
=string_list_to_word(dict_lookup(dict
,"log-events"),
2212 log_event_table
,"site");
2214 st
->resolving_count
=0;
2215 st
->allow_send_prod
=0;
2217 st
->tunname
=safe_malloc(strlen(st
->localname
)+strlen(st
->remotename
)+5,
2219 sprintf(st
->tunname
,"%s<->%s",st
->localname
,st
->remotename
);
2221 /* The information we expect to see in incoming messages of type 1 */
2222 /* fixme: lots of unchecked overflows here, but the results are only
2223 corrupted packets rather than undefined behaviour */
2224 st
->our_name_later
=(strcmp(st
->localname
,st
->remotename
)>0);
2226 buffer_new(&st
->buffer
,SETUP_BUFFER_LEN
);
2228 buffer_new(&st
->scratch
,SETUP_BUFFER_LEN
);
2229 BUF_ALLOC(&st
->scratch
,"site:scratch");
2231 /* We are interested in poll(), but only for timeouts. We don't have
2232 any fds of our own. */
2233 register_for_poll(st
, site_beforepoll
, site_afterpoll
, "site");
2236 st
->remote_capabilities
=0;
2237 st
->chosen_transform
=0;
2238 st
->current
.key_timeout
=0;
2239 st
->auxiliary_key
.key_timeout
=0;
2240 transport_peers_clear(st
,&st
->peers
);
2241 transport_peers_clear(st
,&st
->setup_peers
);
2242 /* XXX mlock these */
2243 st
->dhsecret
=safe_malloc(st
->dh
->len
,"site:dhsecret");
2244 st
->sharedsecretlen
=st
->sharedsecretallocd
=0;
2247 #define SET_CAPBIT(bit) do { \
2248 uint32_t capflag = 1UL << (bit); \
2249 if (st->local_capabilities & capflag) \
2250 slog(st,LOG_ERROR,"capability bit" \
2251 " %d (%#"PRIx32") reused", (bit), capflag); \
2252 st->local_capabilities |= capflag; \
2255 for (i
=0; i
<st
->ntransforms
; i
++)
2256 SET_CAPBIT(st
->transforms
[i
]->capab_bit
);
2260 if (st
->local_mobile
|| st
->peer_mobile
)
2261 st
->local_capabilities
|= CAPAB_PRIORITY_MOBILE
;
2263 /* We need to register the remote networks with the netlink device */
2264 uint32_t netlink_mtu
; /* local virtual interface mtu */
2265 st
->netlink
->reg(st
->netlink
->st
, site_outgoing
, st
, &netlink_mtu
);
2266 if (!st
->mtu_target
)
2267 st
->mtu_target
=netlink_mtu
;
2269 for (i
=0; i
<st
->ncomms
; i
++)
2270 st
->comms
[i
]->request_notify(st
->comms
[i
]->st
, st
, site_incoming
);
2272 st
->current
.transform
=0;
2273 st
->auxiliary_key
.transform
=0;
2274 st
->new_transform
=0;
2275 st
->auxiliary_is_new
=0;
2277 enter_state_stop(st
);
2279 add_hook(PHASE_SHUTDOWN
,site_phase_hook
,st
);
2280 add_hook(PHASE_CHILDPERSIST
,site_childpersist_clearkeys
,st
);
2282 return new_closure(&st
->cl
);
2285 void site_module(dict_t
*dict
)
2287 add_closure(dict
,"site",site_apply
);
2291 /***** TRANSPORT PEERS definitions *****/
2293 static void transport_peers_debug(struct site
*st
, transport_peers
*dst
,
2294 const char *didwhat
,
2295 int nargs
, const struct comm_addr
*args
,
2300 if (!(st
->log_events
& LOG_PEER_ADDRS
))
2301 return; /* an optimisation */
2303 slog(st
, LOG_PEER_ADDRS
, "peers (%s) %s nargs=%d => npeers=%d",
2304 (dst
==&st
->peers ?
"data" :
2305 dst
==&st
->setup_peers ?
"setup" : "UNKNOWN"),
2306 didwhat
, nargs
, dst
->npeers
);
2308 for (i
=0, argp
=(void*)args
;
2310 i
++, (argp
+=stride?stride
:sizeof(*args
))) {
2311 const struct comm_addr
*ca
=(void*)argp
;
2312 slog(st
, LOG_PEER_ADDRS
, " args: addrs[%d]=%s",
2313 i
, comm_addr_to_string(ca
));
2315 for (i
=0; i
<dst
->npeers
; i
++) {
2316 struct timeval diff
;
2317 timersub(tv_now
,&dst
->peers
[i
].last
,&diff
);
2318 const struct comm_addr
*ca
=&dst
->peers
[i
].addr
;
2319 slog(st
, LOG_PEER_ADDRS
, " peers: addrs[%d]=%s T-%ld.%06ld",
2320 i
, comm_addr_to_string(ca
),
2321 (unsigned long)diff
.tv_sec
, (unsigned long)diff
.tv_usec
);
2325 static void transport_peers_expire(struct site
*st
, transport_peers
*peers
) {
2326 /* peers must be sorted first */
2327 int previous_peers
=peers
->npeers
;
2328 struct timeval oldest
;
2329 oldest
.tv_sec
= tv_now
->tv_sec
- st
->mobile_peer_expiry
;
2330 oldest
.tv_usec
= tv_now
->tv_usec
;
2331 while (peers
->npeers
>1 &&
2332 timercmp(&peers
->peers
[peers
->npeers
-1].last
, &oldest
, <))
2334 if (peers
->npeers
!= previous_peers
)
2335 transport_peers_debug(st
,peers
,"expire", 0,0,0);
2338 static bool_t
transport_peer_record_one(struct site
*st
, transport_peers
*peers
,
2339 const struct comm_addr
*ca
,
2340 const struct timeval
*tv
) {
2341 /* returns false if output is full */
2344 if (peers
->npeers
>= st
->transport_peers_max
)
2347 for (search
=0; search
<peers
->npeers
; search
++)
2348 if (comm_addr_equal(&peers
->peers
[search
].addr
, ca
))
2351 peers
->peers
[peers
->npeers
].addr
= *ca
;
2352 peers
->peers
[peers
->npeers
].last
= *tv
;
2357 static void transport_record_peers(struct site
*st
, transport_peers
*peers
,
2358 const struct comm_addr
*addrs
, int naddrs
,
2360 /* We add addrs into peers. The new entries end up at the front
2361 * and displace entries towards the end (perhaps even off the
2362 * end). Any existing matching entries are moved up to the front.
2364 * Caller must first call transport_peers_expire. */
2367 /* avoids debug for uninteresting updates */
2369 for (i
=0; i
<peers
->npeers
; i
++) {
2370 if (comm_addr_equal(&addrs
[0], &peers
->peers
[i
].addr
)) {
2371 memmove(peers
->peers
+1, peers
->peers
,
2372 sizeof(peers
->peers
[0]) * i
);
2373 peers
->peers
[0].addr
= addrs
[0];
2374 peers
->peers
[0].last
= *tv_now
;
2380 int old_npeers
=peers
->npeers
;
2381 transport_peer old_peers
[old_npeers
];
2382 COPY_ARRAY(old_peers
,peers
->peers
,old_npeers
);
2386 for (i
=0; i
<naddrs
; i
++) {
2387 if (!transport_peer_record_one(st
,peers
, &addrs
[i
], tv_now
))
2390 for (i
=0; i
<old_npeers
; i
++) {
2391 const transport_peer
*old
=&old_peers
[i
];
2392 if (!transport_peer_record_one(st
,peers
, &old
->addr
, &old
->last
))
2396 transport_peers_debug(st
,peers
,m
, naddrs
,addrs
,0);
2399 static void transport_expire_record_peers(struct site
*st
,
2400 transport_peers
*peers
,
2401 const struct comm_addr
*addrs
,
2402 int naddrs
, const char *m
) {
2403 /* Convenience function */
2404 transport_peers_expire(st
,peers
);
2405 transport_record_peers(st
,peers
,addrs
,naddrs
,m
);
2408 static bool_t
transport_compute_setupinit_peers(struct site
*st
,
2409 const struct comm_addr
*configured_addrs
/* 0 if none or not found */,
2410 int n_configured_addrs
/* 0 if none or not found */,
2411 const struct comm_addr
*incoming_packet_addr
/* 0 if none */) {
2412 if (!n_configured_addrs
&& !incoming_packet_addr
&&
2413 !transport_peers_valid(&st
->peers
))
2416 slog(st
,LOG_SETUP_INIT
,
2417 "using: %d configured addr(s);%s %d old peer addrs(es)",
2419 incoming_packet_addr ?
" incoming packet address;" : "",
2422 /* Non-mobile peers try addresses until one is plausible. The
2423 * effect is that this code always tries first the configured
2424 * address if supplied, or otherwise the address of the incoming
2425 * PROD, or finally the existing data peer if one exists; this is
2428 transport_peers_copy(st
,&st
->setup_peers
,&st
->peers
);
2429 transport_peers_expire(st
,&st
->setup_peers
);
2431 if (incoming_packet_addr
)
2432 transport_record_peers(st
,&st
->setup_peers
,
2433 incoming_packet_addr
,1, "incoming");
2435 if (n_configured_addrs
)
2436 transport_record_peers(st
,&st
->setup_peers
,
2437 configured_addrs
,n_configured_addrs
, "setupinit");
2439 assert(transport_peers_valid(&st
->setup_peers
));
2443 static void transport_setup_msgok(struct site
*st
, const struct comm_addr
*a
) {
2444 if (st
->peer_mobile
)
2445 transport_expire_record_peers(st
,&st
->setup_peers
,a
,1,"setupmsg");
2447 static void transport_data_msgok(struct site
*st
, const struct comm_addr
*a
) {
2448 if (st
->peer_mobile
)
2449 transport_expire_record_peers(st
,&st
->peers
,a
,1,"datamsg");
2452 static int transport_peers_valid(transport_peers
*peers
) {
2453 return peers
->npeers
;
2455 static void transport_peers_clear(struct site
*st
, transport_peers
*peers
) {
2457 transport_peers_debug(st
,peers
,"clear",0,0,0);
2459 static void transport_peers_copy(struct site
*st
, transport_peers
*dst
,
2460 const transport_peers
*src
) {
2461 dst
->npeers
=src
->npeers
;
2462 COPY_ARRAY(dst
->peers
, src
->peers
, dst
->npeers
);
2463 transport_peers_debug(st
,dst
,"copy",
2464 src
->npeers
, &src
->peers
->addr
, sizeof(*src
->peers
));
2467 static void transport_resolve_complete(struct site
*st
,
2468 const struct comm_addr
*addrs
,
2470 transport_expire_record_peers(st
,&st
->peers
,addrs
,naddrs
,
2472 transport_expire_record_peers(st
,&st
->setup_peers
,addrs
,naddrs
,
2476 static void transport_resolve_complete_tardy(struct site
*st
,
2477 const struct comm_addr
*addrs
,
2479 transport_expire_record_peers(st
,&st
->peers
,addrs
,naddrs
,
2480 "resolved tardily");
2483 static void transport_peers__copy_by_mask(transport_peer
*out
, int *nout_io
,
2485 const transport_peers
*inp
) {
2486 /* out and in->peers may be the same region, or nonoverlapping */
2487 const transport_peer
*in
=inp
->peers
;
2489 for (slot
=0; slot
<inp
->npeers
; slot
++) {
2490 if (!(mask
& (1U << slot
)))
2492 if (!(out
==in
&& slot
==*nout_io
))
2493 COPY_OBJ(out
[*nout_io
], in
[slot
]);
2498 void transport_xmit(struct site
*st
, transport_peers
*peers
,
2499 struct buffer_if
*buf
, bool_t candebug
) {
2501 transport_peers_expire(st
, peers
);
2502 unsigned failed
=0; /* bitmask */
2503 assert(MAX_PEER_ADDRS
< sizeof(unsigned)*CHAR_BIT
);
2506 for (slot
=0; slot
<peers
->npeers
; slot
++) {
2507 transport_peer
*peer
=&peers
->peers
[slot
];
2508 bool_t ok
= comm_addr_sendmsg(st
, &peer
->addr
, buf
);
2510 dump_packet(st
, buf
, &peer
->addr
, False
, ok
);
2512 failed
|= 1U << slot
;
2515 if (ok
&& !st
->peer_mobile
)
2518 /* Now we need to demote/delete failing addrs: if we are mobile we
2519 * merely demote them; otherwise we delete them. */
2520 if (st
->local_mobile
) {
2521 unsigned expected
= ((1U << nfailed
)-1) << (peers
->npeers
-nfailed
);
2522 /* `expected' has all the failures at the end already */
2523 if (failed
!= expected
) {
2525 transport_peer failedpeers
[nfailed
];
2526 transport_peers__copy_by_mask(failedpeers
, &fslot
, failed
,peers
);
2527 assert(fslot
== nfailed
);
2529 transport_peers__copy_by_mask(peers
->peers
,&wslot
,~failed
,peers
);
2530 assert(wslot
+nfailed
== peers
->npeers
);
2531 COPY_ARRAY(peers
->peers
+wslot
, failedpeers
, nfailed
);
2532 transport_peers_debug(st
,peers
,"mobile failure reorder",0,0,0);
2535 if (failed
&& peers
->npeers
> 1) {
2537 transport_peers__copy_by_mask(peers
->peers
,&wslot
,~failed
,peers
);
2538 peers
->npeers
=wslot
;
2539 transport_peers_debug(st
,peers
,"non-mobile failure cleanup",0,0,0);
2544 /***** END of transport peers declarations *****/