Commit | Line | Data |
---|---|---|
2fe58dfd SE |
1 | /* site.c - manage communication with a remote network site */ |
2 | ||
469fd1d9 SE |
3 | /* The 'site' code doesn't know anything about the structure of the |
4 | packets it's transmitting. In fact, under the new netlink | |
5 | configuration scheme it doesn't need to know anything at all about | |
6 | IP addresses, except how to contact its peer. This means it could | |
7 | potentially be used to tunnel other protocols too (IPv6, IPX, plain | |
8 | old Ethernet frames) if appropriate netlink code can be written | |
9 | (and that ought not to be too hard, eg. using the TUN/TAP device to | |
10 | pretend to be an Ethernet interface). */ | |
11 | ||
ff05a229 SE |
12 | /* At some point in the future the netlink code will be asked for |
13 | configuration information to go in the PING/PONG packets at the end | |
14 | of the key exchange. */ | |
15 | ||
8689b3a9 | 16 | #include "secnet.h" |
2fe58dfd | 17 | #include <stdio.h> |
469fd1d9 | 18 | #include <string.h> |
fe5e9cc4 | 19 | #include <limits.h> |
58650a70 | 20 | #include <assert.h> |
8689b3a9 | 21 | #include <sys/socket.h> |
2fe58dfd | 22 | |
8689b3a9 | 23 | #include <sys/mman.h> |
2fe58dfd | 24 | #include "util.h" |
59635212 | 25 | #include "unaligned.h" |
ff05a229 | 26 | #include "magic.h" |
2fe58dfd SE |
27 | |
28 | #define SETUP_BUFFER_LEN 2048 | |
29 | ||
e7f8ec2a IJ |
30 | #define DEFAULT_KEY_LIFETIME (3600*1000) /* [ms] */ |
31 | #define DEFAULT_KEY_RENEGOTIATE_GAP (5*60*1000) /* [ms] */ | |
2fe58dfd | 32 | #define DEFAULT_SETUP_RETRIES 5 |
e7f8ec2a IJ |
33 | #define DEFAULT_SETUP_RETRY_INTERVAL (2*1000) /* [ms] */ |
34 | #define DEFAULT_WAIT_TIME (20*1000) /* [ms] */ | |
e57264d6 IJ |
35 | |
36 | #define DEFAULT_MOBILE_KEY_LIFETIME (2*24*3600*1000) /* [ms] */ | |
37 | #define DEFAULT_MOBILE_KEY_RENEGOTIATE_GAP (12*3600*1000) /* [ms] */ | |
38 | #define DEFAULT_MOBILE_SETUP_RETRIES 30 | |
39 | #define DEFAULT_MOBILE_SETUP_RETRY_INTERVAL (1*1000) /* [ms] */ | |
40 | #define DEFAULT_MOBILE_WAIT_TIME (10*1000) /* [ms] */ | |
41 | ||
446353cd IJ |
42 | #define DEFAULT_MOBILE_PEER_EXPIRY (2*60) /* [s] */ |
43 | #define DEFAULT_MOBILE_PEERS_MAX 3 /* send at most this many copies (default) */ | |
2fe58dfd SE |
44 | |
45 | /* Each site can be in one of several possible states. */ | |
46 | ||
47 | /* States: | |
48 | SITE_STOP - nothing is allowed to happen; tunnel is down; | |
49 | all session keys have been erased | |
50 | -> SITE_RUN upon external instruction | |
51 | SITE_RUN - site up, maybe with valid key | |
52 | -> SITE_RESOLVE upon outgoing packet and no valid key | |
53 | we start name resolution for the other end of the tunnel | |
54 | -> SITE_SENTMSG2 upon valid incoming message 1 and suitable time | |
55 | we send an appropriate message 2 | |
56 | SITE_RESOLVE - waiting for name resolution | |
57 | -> SITE_SENTMSG1 upon successful resolution | |
58 | we send an appropriate message 1 | |
59 | -> SITE_SENTMSG2 upon valid incoming message 1 (then abort resolution) | |
60 | we abort resolution and | |
61 | -> SITE_WAIT on timeout or resolution failure | |
62 | SITE_SENTMSG1 | |
63 | -> SITE_SENTMSG2 upon valid incoming message 1 from higher priority end | |
64 | -> SITE_SENTMSG3 upon valid incoming message 2 | |
65 | -> SITE_WAIT on timeout | |
66 | SITE_SENTMSG2 | |
67 | -> SITE_SENTMSG4 upon valid incoming message 3 | |
68 | -> SITE_WAIT on timeout | |
69 | SITE_SENTMSG3 | |
70 | -> SITE_SENTMSG5 upon valid incoming message 4 | |
71 | -> SITE_WAIT on timeout | |
72 | SITE_SENTMSG4 | |
73 | -> SITE_RUN upon valid incoming message 5 | |
74 | -> SITE_WAIT on timeout | |
75 | SITE_SENTMSG5 | |
76 | -> SITE_RUN upon valid incoming message 6 | |
77 | -> SITE_WAIT on timeout | |
78 | SITE_WAIT - failed to establish key; do nothing for a while | |
79 | -> SITE_RUN on timeout | |
80 | */ | |
81 | ||
82 | #define SITE_STOP 0 | |
83 | #define SITE_RUN 1 | |
84 | #define SITE_RESOLVE 2 | |
85 | #define SITE_SENTMSG1 3 | |
86 | #define SITE_SENTMSG2 4 | |
87 | #define SITE_SENTMSG3 5 | |
88 | #define SITE_SENTMSG4 6 | |
89 | #define SITE_SENTMSG5 7 | |
90 | #define SITE_WAIT 8 | |
91 | ||
fe5e9cc4 | 92 | static cstring_t state_name(uint32_t state) |
2fe58dfd SE |
93 | { |
94 | switch (state) { | |
3454dce4 SE |
95 | case 0: return "STOP"; |
96 | case 1: return "RUN"; | |
97 | case 2: return "RESOLVE"; | |
98 | case 3: return "SENTMSG1"; | |
99 | case 4: return "SENTMSG2"; | |
100 | case 5: return "SENTMSG3"; | |
101 | case 6: return "SENTMSG4"; | |
102 | case 7: return "SENTMSG5"; | |
103 | case 8: return "WAIT"; | |
2fe58dfd SE |
104 | default: return "*bad state*"; |
105 | } | |
106 | } | |
107 | ||
2fe58dfd SE |
108 | #define NONCELEN 8 |
109 | ||
110 | #define LOG_UNEXPECTED 0x00000001 | |
111 | #define LOG_SETUP_INIT 0x00000002 | |
112 | #define LOG_SETUP_TIMEOUT 0x00000004 | |
113 | #define LOG_ACTIVATE_KEY 0x00000008 | |
114 | #define LOG_TIMEOUT_KEY 0x00000010 | |
9d3a4132 | 115 | #define LOG_SEC 0x00000020 |
2fe58dfd SE |
116 | #define LOG_STATE 0x00000040 |
117 | #define LOG_DROP 0x00000080 | |
118 | #define LOG_DUMP 0x00000100 | |
119 | #define LOG_ERROR 0x00000400 | |
446353cd | 120 | #define LOG_PEER_ADDRS 0x00000800 |
2fe58dfd | 121 | |
9d3a4132 SE |
122 | static struct flagstr log_event_table[]={ |
123 | { "unexpected", LOG_UNEXPECTED }, | |
124 | { "setup-init", LOG_SETUP_INIT }, | |
125 | { "setup-timeout", LOG_SETUP_TIMEOUT }, | |
126 | { "activate-key", LOG_ACTIVATE_KEY }, | |
127 | { "timeout-key", LOG_TIMEOUT_KEY }, | |
128 | { "security", LOG_SEC }, | |
129 | { "state-change", LOG_STATE }, | |
130 | { "packet-drop", LOG_DROP }, | |
131 | { "dump-packets", LOG_DUMP }, | |
132 | { "errors", LOG_ERROR }, | |
446353cd | 133 | { "peer-addrs", LOG_PEER_ADDRS }, |
ff05a229 SE |
134 | { "default", LOG_SETUP_INIT|LOG_SETUP_TIMEOUT| |
135 | LOG_ACTIVATE_KEY|LOG_TIMEOUT_KEY|LOG_SEC|LOG_ERROR }, | |
9d3a4132 SE |
136 | { "all", 0xffffffff }, |
137 | { NULL, 0 } | |
138 | }; | |
139 | ||
446353cd IJ |
140 | |
141 | /***** TRANSPORT PEERS declarations *****/ | |
142 | ||
143 | /* Details of "mobile peer" semantics: | |
144 | ||
145 | - We record mobile_peers_max peer address/port numbers ("peers") | |
146 | for key setup, and separately mobile_peers_max for data | |
147 | transfer. If these lists fill up, we retain the newest peers. | |
148 | (For non-mobile peers we only record one of each.) | |
149 | ||
150 | - Outgoing packets are sent to every recorded peer in the | |
151 | applicable list. | |
152 | ||
153 | - Data transfer peers are straightforward: whenever we successfully | |
154 | process a data packet, we record the peer. Also, whenever we | |
155 | successfully complete a key setup, we merge the key setup | |
156 | peers into the data transfer peers. | |
157 | ||
158 | (For "non-mobile" peers we simply copy the peer used for | |
159 | successful key setup, and don't change the peer otherwise.) | |
160 | ||
161 | - Key setup peers are slightly more complicated. | |
162 | ||
163 | Whenever we receive and successfully process a key exchange | |
164 | packet, we record the peer. | |
165 | ||
166 | Whenever we try to initiate a key setup, we copy the list of data | |
167 | transfer peers and use it for key setup. But we also look to see | |
168 | if the config supplies an address and port number and if so we | |
169 | add that as a key setup peer (possibly evicting one of the data | |
170 | transfer peers we just copied). | |
171 | ||
172 | (For "non-mobile" peers, if we if we have a configured peer | |
173 | address and port, we always use that; otherwise if we have a | |
174 | current data peer address we use that; otherwise we do not | |
175 | attempt to initiate a key setup for lack of a peer address.) | |
176 | ||
177 | "Record the peer" means | |
178 | 1. expire any peers last seen >120s ("mobile-peer-expiry") ago | |
179 | 2. add the peer of the just received packet to the applicable list | |
180 | (possibly evicting older entries) | |
181 | NB that we do not expire peers until an incoming packet arrives. | |
182 | ||
183 | */ | |
184 | ||
185 | #define MAX_MOBILE_PEERS_MAX 5 /* send at most this many copies, compiled max */ | |
186 | ||
187 | typedef struct { | |
188 | struct timeval last; | |
189 | struct comm_addr addr; | |
190 | } transport_peer; | |
191 | ||
192 | typedef struct { | |
193 | /* configuration information */ | |
194 | /* runtime information */ | |
195 | int npeers; | |
196 | transport_peer peers[MAX_MOBILE_PEERS_MAX]; | |
197 | } transport_peers; | |
198 | ||
199 | static void transport_peers_clear(struct site *st, transport_peers *peers); | |
200 | static int transport_peers_valid(transport_peers *peers); | |
201 | static void transport_peers_copy(struct site *st, transport_peers *dst, | |
202 | const transport_peers *src); | |
203 | ||
204 | static void transport_setup_msgok(struct site *st, const struct comm_addr *a); | |
205 | static void transport_data_msgok(struct site *st, const struct comm_addr *a); | |
206 | static bool_t transport_compute_setupinit_peers(struct site *st, | |
207 | const struct comm_addr *configured_addr /* 0 if none or not found */); | |
208 | static void transport_record_peer(struct site *st, transport_peers *peers, | |
209 | const struct comm_addr *addr, const char *m); | |
210 | ||
211 | static void transport_xmit(struct site *st, transport_peers *peers, | |
212 | struct buffer_if *buf, bool_t candebug); | |
213 | ||
214 | /***** END of transport peers declarations *****/ | |
215 | ||
216 | ||
19e9a588 IJ |
217 | struct data_key { |
218 | struct transform_inst_if *transform; | |
219 | uint64_t key_timeout; /* End of life of current key */ | |
220 | uint32_t remote_session_id; | |
221 | }; | |
222 | ||
2fe58dfd SE |
223 | struct site { |
224 | closure_t cl; | |
225 | struct site_if ops; | |
226 | /* configuration information */ | |
227 | string_t localname; | |
228 | string_t remotename; | |
446353cd IJ |
229 | bool_t peer_mobile; /* Mobile client support */ |
230 | int32_t transport_peers_max; | |
ff05a229 | 231 | string_t tunname; /* localname<->remotename by default, used in logs */ |
2fe58dfd | 232 | string_t address; /* DNS name for bootstrapping, optional */ |
ff05a229 | 233 | int remoteport; /* Port for bootstrapping, optional */ |
2fe58dfd | 234 | struct netlink_if *netlink; |
59533c16 IJ |
235 | struct comm_if **comms; |
236 | int ncomms; | |
2fe58dfd SE |
237 | struct resolver_if *resolver; |
238 | struct log_if *log; | |
239 | struct random_if *random; | |
240 | struct rsaprivkey_if *privkey; | |
2fe58dfd SE |
241 | struct rsapubkey_if *pubkey; |
242 | struct transform_if *transform; | |
243 | struct dh_if *dh; | |
244 | struct hash_if *hash; | |
2fe58dfd | 245 | |
58650a70 | 246 | uint32_t index; /* Index of this site */ |
1caa23ff | 247 | int32_t setup_retries; /* How many times to send setup packets */ |
e7f8ec2a | 248 | int32_t setup_retry_interval; /* Initial timeout for setup packets */ |
4a8aed08 | 249 | int32_t wait_timeout; /* How long to wait if setup unsuccessful */ |
446353cd | 250 | int32_t mobile_peer_expiry; /* How long to remember 2ary addresses */ |
4a8aed08 IJ |
251 | int32_t key_lifetime; /* How long a key lasts once set up */ |
252 | int32_t key_renegotiate_time; /* If we see traffic (or a keepalive) | |
9d3a4132 SE |
253 | after this time, initiate a new |
254 | key exchange */ | |
2fe58dfd SE |
255 | |
256 | uint8_t *setupsig; /* Expected signature of incoming MSG1 packets */ | |
1caa23ff IJ |
257 | int32_t setupsiglen; /* Allows us to discard packets quickly if |
258 | they are not for us */ | |
2fe58dfd SE |
259 | bool_t setup_priority; /* Do we have precedence if both sites emit |
260 | message 1 simultaneously? */ | |
261 | uint32_t log_events; | |
262 | ||
263 | /* runtime information */ | |
264 | uint32_t state; | |
265 | uint64_t now; /* Most recently seen time */ | |
266 | ||
ff05a229 | 267 | /* The currently established session */ |
19e9a588 | 268 | struct data_key current; |
02b0959b | 269 | struct data_key auxiliary_key; |
bd98cd6b | 270 | bool_t auxiliary_is_new; |
ff05a229 | 271 | uint64_t renegotiate_key_time; /* When we can negotiate a new key */ |
bd98cd6b | 272 | uint64_t auxiliary_renegotiate_key_time; |
446353cd | 273 | transport_peers peers; /* Current address(es) of peer for data traffic */ |
2fe58dfd | 274 | |
ff05a229 SE |
275 | /* The current key setup protocol exchange. We can only be |
276 | involved in one of these at a time. There's a potential for | |
277 | denial of service here (the attacker keeps sending a setup | |
278 | packet; we keep trying to continue the exchange, and have to | |
279 | timeout before we can listen for another setup packet); perhaps | |
280 | we should keep a list of 'bad' sources for setup packets. */ | |
2fe58dfd | 281 | uint32_t setup_session_id; |
446353cd | 282 | transport_peers setup_peers; |
2fe58dfd SE |
283 | uint8_t localN[NONCELEN]; /* Nonces for key exchange */ |
284 | uint8_t remoteN[NONCELEN]; | |
285 | struct buffer_if buffer; /* Current outgoing key exchange packet */ | |
05f39b4d | 286 | struct buffer_if scratch; |
4a8aed08 | 287 | int32_t retries; /* Number of retries remaining */ |
2fe58dfd SE |
288 | uint64_t timeout; /* Timeout for current state */ |
289 | uint8_t *dhsecret; | |
290 | uint8_t *sharedsecret; | |
7c9ca4bd | 291 | uint32_t sharedsecretlen; |
2fe58dfd SE |
292 | struct transform_inst_if *new_transform; /* For key setup/verify */ |
293 | }; | |
294 | ||
fe5e9cc4 | 295 | static void slog(struct site *st, uint32_t event, cstring_t msg, ...) |
2fe58dfd SE |
296 | { |
297 | va_list ap; | |
7c006408 | 298 | char buf[240]; |
b2a56f7c | 299 | uint32_t class; |
2fe58dfd SE |
300 | |
301 | va_start(ap,msg); | |
302 | ||
303 | if (event&st->log_events) { | |
b2a56f7c SE |
304 | switch(event) { |
305 | case LOG_UNEXPECTED: class=M_INFO; break; | |
306 | case LOG_SETUP_INIT: class=M_INFO; break; | |
307 | case LOG_SETUP_TIMEOUT: class=M_NOTICE; break; | |
308 | case LOG_ACTIVATE_KEY: class=M_INFO; break; | |
309 | case LOG_TIMEOUT_KEY: class=M_INFO; break; | |
310 | case LOG_SEC: class=M_SECURITY; break; | |
311 | case LOG_STATE: class=M_DEBUG; break; | |
312 | case LOG_DROP: class=M_DEBUG; break; | |
313 | case LOG_DUMP: class=M_DEBUG; break; | |
469fd1d9 | 314 | case LOG_ERROR: class=M_ERR; break; |
446353cd | 315 | case LOG_PEER_ADDRS: class=M_DEBUG; break; |
469fd1d9 | 316 | default: class=M_ERR; break; |
b2a56f7c SE |
317 | } |
318 | ||
c1d2109a | 319 | vsnprintf(buf,sizeof(buf),msg,ap); |
b2a56f7c | 320 | st->log->log(st->log->st,class,"%s: %s",st->tunname,buf); |
2fe58dfd SE |
321 | } |
322 | va_end(ap); | |
323 | } | |
324 | ||
9d3a4132 | 325 | static void set_link_quality(struct site *st); |
1d388569 IJ |
326 | static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel); |
327 | static void delete_one_key(struct site *st, struct data_key *key, | |
328 | const char *reason /* may be 0 meaning don't log*/, | |
329 | const char *which /* ignored if !reasonn */, | |
330 | uint32_t loglevel /* ignored if !reasonn */); | |
fe5e9cc4 | 331 | static bool_t initiate_key_setup(struct site *st, cstring_t reason); |
2fe58dfd SE |
332 | static void enter_state_run(struct site *st); |
333 | static bool_t enter_state_resolve(struct site *st); | |
ff05a229 | 334 | static bool_t enter_new_state(struct site *st,uint32_t next); |
2fe58dfd | 335 | static void enter_state_wait(struct site *st); |
05f39b4d | 336 | static void activate_new_key(struct site *st); |
2fe58dfd | 337 | |
3d8d8f4e IJ |
338 | static bool_t current_valid(struct site *st) |
339 | { | |
19e9a588 | 340 | return st->current.transform->valid(st->current.transform->st); |
3d8d8f4e IJ |
341 | } |
342 | ||
2fe58dfd SE |
343 | #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0) |
344 | #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0) | |
345 | #define CHECK_TYPE(b,t) do { uint32_t type; \ | |
346 | CHECK_AVAIL((b),4); \ | |
59635212 | 347 | type=buf_unprepend_uint32((b)); \ |
2fe58dfd SE |
348 | if (type!=(t)) return False; } while(0) |
349 | ||
350 | struct msg { | |
351 | uint8_t *hashstart; | |
352 | uint32_t dest; | |
353 | uint32_t source; | |
1caa23ff | 354 | int32_t remlen; |
2fe58dfd | 355 | uint8_t *remote; |
1caa23ff | 356 | int32_t loclen; |
2fe58dfd SE |
357 | uint8_t *local; |
358 | uint8_t *nR; | |
359 | uint8_t *nL; | |
1caa23ff | 360 | int32_t pklen; |
3e8addad | 361 | char *pk; |
1caa23ff IJ |
362 | int32_t hashlen; |
363 | int32_t siglen; | |
3e8addad | 364 | char *sig; |
2fe58dfd SE |
365 | }; |
366 | ||
ff05a229 SE |
367 | /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside |
368 | out using a transform of config data supplied by netlink */ | |
fe5e9cc4 | 369 | static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what) |
2fe58dfd SE |
370 | { |
371 | void *hst; | |
3b83c932 | 372 | uint8_t *hash; |
2fe58dfd SE |
373 | string_t dhpub, sig; |
374 | ||
375 | st->retries=st->setup_retries; | |
376 | BUF_ALLOC(&st->buffer,what); | |
377 | buffer_init(&st->buffer,0); | |
59635212 SE |
378 | buf_append_uint32(&st->buffer, |
379 | (type==LABEL_MSG1?0:st->setup_session_id)); | |
58650a70 | 380 | buf_append_uint32(&st->buffer,st->index); |
59635212 | 381 | buf_append_uint32(&st->buffer,type); |
2fe58dfd SE |
382 | buf_append_string(&st->buffer,st->localname); |
383 | buf_append_string(&st->buffer,st->remotename); | |
384 | memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN); | |
385 | if (type==LABEL_MSG1) return True; | |
386 | memcpy(buf_append(&st->buffer,NONCELEN),st->remoteN,NONCELEN); | |
387 | if (type==LABEL_MSG2) return True; | |
3b83c932 SE |
388 | |
389 | if (hacky_par_mid_failnow()) return False; | |
390 | ||
2fe58dfd SE |
391 | dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len); |
392 | buf_append_string(&st->buffer,dhpub); | |
393 | free(dhpub); | |
3b83c932 | 394 | hash=safe_malloc(st->hash->len, "generate_msg"); |
2fe58dfd SE |
395 | hst=st->hash->init(); |
396 | st->hash->update(hst,st->buffer.start,st->buffer.size); | |
397 | st->hash->final(hst,hash); | |
398 | sig=st->privkey->sign(st->privkey->st,hash,st->hash->len); | |
399 | buf_append_string(&st->buffer,sig); | |
400 | free(sig); | |
3b83c932 | 401 | free(hash); |
2fe58dfd SE |
402 | return True; |
403 | } | |
404 | ||
405 | static bool_t unpick_msg(struct site *st, uint32_t type, | |
406 | struct buffer_if *msg, struct msg *m) | |
407 | { | |
408 | m->hashstart=msg->start; | |
409 | CHECK_AVAIL(msg,4); | |
59635212 | 410 | m->dest=buf_unprepend_uint32(msg); |
2fe58dfd | 411 | CHECK_AVAIL(msg,4); |
59635212 | 412 | m->source=buf_unprepend_uint32(msg); |
2fe58dfd SE |
413 | CHECK_TYPE(msg,type); |
414 | CHECK_AVAIL(msg,2); | |
59635212 | 415 | m->remlen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
416 | CHECK_AVAIL(msg,m->remlen); |
417 | m->remote=buf_unprepend(msg,m->remlen); | |
418 | CHECK_AVAIL(msg,2); | |
59635212 | 419 | m->loclen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
420 | CHECK_AVAIL(msg,m->loclen); |
421 | m->local=buf_unprepend(msg,m->loclen); | |
422 | CHECK_AVAIL(msg,NONCELEN); | |
423 | m->nR=buf_unprepend(msg,NONCELEN); | |
424 | if (type==LABEL_MSG1) { | |
425 | CHECK_EMPTY(msg); | |
426 | return True; | |
427 | } | |
428 | CHECK_AVAIL(msg,NONCELEN); | |
429 | m->nL=buf_unprepend(msg,NONCELEN); | |
430 | if (type==LABEL_MSG2) { | |
431 | CHECK_EMPTY(msg); | |
432 | return True; | |
433 | } | |
434 | CHECK_AVAIL(msg,2); | |
59635212 | 435 | m->pklen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
436 | CHECK_AVAIL(msg,m->pklen); |
437 | m->pk=buf_unprepend(msg,m->pklen); | |
438 | m->hashlen=msg->start-m->hashstart; | |
439 | CHECK_AVAIL(msg,2); | |
59635212 | 440 | m->siglen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
441 | CHECK_AVAIL(msg,m->siglen); |
442 | m->sig=buf_unprepend(msg,m->siglen); | |
443 | CHECK_EMPTY(msg); | |
444 | return True; | |
445 | } | |
446 | ||
ff05a229 | 447 | static bool_t check_msg(struct site *st, uint32_t type, struct msg *m, |
fe5e9cc4 | 448 | cstring_t *error) |
ff05a229 SE |
449 | { |
450 | if (type==LABEL_MSG1) return True; | |
451 | ||
452 | /* Check that the site names and our nonce have been sent | |
453 | back correctly, and then store our peer's nonce. */ | |
454 | if (memcmp(m->remote,st->remotename,strlen(st->remotename)!=0)) { | |
455 | *error="wrong remote site name"; | |
456 | return False; | |
457 | } | |
458 | if (memcmp(m->local,st->localname,strlen(st->localname)!=0)) { | |
459 | *error="wrong local site name"; | |
460 | return False; | |
461 | } | |
462 | if (memcmp(m->nL,st->localN,NONCELEN)!=0) { | |
463 | *error="wrong locally-generated nonce"; | |
464 | return False; | |
465 | } | |
466 | if (type==LABEL_MSG2) return True; | |
5ad34db2 | 467 | if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) { |
ff05a229 SE |
468 | *error="wrong remotely-generated nonce"; |
469 | return False; | |
470 | } | |
471 | if (type==LABEL_MSG3) return True; | |
472 | if (type==LABEL_MSG4) return True; | |
473 | *error="unknown message type"; | |
474 | return False; | |
475 | } | |
476 | ||
2fe58dfd SE |
477 | static bool_t generate_msg1(struct site *st) |
478 | { | |
479 | st->random->generate(st->random->st,NONCELEN,st->localN); | |
480 | return generate_msg(st,LABEL_MSG1,"site:MSG1"); | |
481 | } | |
482 | ||
483 | static bool_t process_msg1(struct site *st, struct buffer_if *msg1, | |
a15faeb2 | 484 | const struct comm_addr *src) |
2fe58dfd SE |
485 | { |
486 | struct msg m; | |
487 | ||
488 | /* We've already determined we're in an appropriate state to | |
489 | process an incoming MSG1, and that the MSG1 has correct values | |
490 | of A and B. */ | |
491 | ||
492 | if (!unpick_msg(st,LABEL_MSG1,msg1,&m)) return False; | |
493 | ||
446353cd | 494 | transport_record_peer(st,&st->setup_peers,src,"msg1"); |
2fe58dfd SE |
495 | st->setup_session_id=m.source; |
496 | memcpy(st->remoteN,m.nR,NONCELEN); | |
497 | return True; | |
498 | } | |
499 | ||
500 | static bool_t generate_msg2(struct site *st) | |
501 | { | |
502 | st->random->generate(st->random->st,NONCELEN,st->localN); | |
503 | return generate_msg(st,LABEL_MSG2,"site:MSG2"); | |
504 | } | |
505 | ||
506 | static bool_t process_msg2(struct site *st, struct buffer_if *msg2, | |
a15faeb2 | 507 | const struct comm_addr *src) |
2fe58dfd SE |
508 | { |
509 | struct msg m; | |
fe5e9cc4 | 510 | cstring_t err; |
2fe58dfd SE |
511 | |
512 | if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False; | |
ff05a229 SE |
513 | if (!check_msg(st,LABEL_MSG2,&m,&err)) { |
514 | slog(st,LOG_SEC,"msg2: %s",err); | |
2fe58dfd SE |
515 | return False; |
516 | } | |
517 | st->setup_session_id=m.source; | |
518 | memcpy(st->remoteN,m.nR,NONCELEN); | |
519 | return True; | |
520 | } | |
521 | ||
522 | static bool_t generate_msg3(struct site *st) | |
523 | { | |
524 | /* Now we have our nonce and their nonce. Think of a secret key, | |
525 | and create message number 3. */ | |
526 | st->random->generate(st->random->st,st->dh->len,st->dhsecret); | |
527 | return generate_msg(st,LABEL_MSG3,"site:MSG3"); | |
528 | } | |
529 | ||
530 | static bool_t process_msg3(struct site *st, struct buffer_if *msg3, | |
a15faeb2 | 531 | const struct comm_addr *src) |
2fe58dfd SE |
532 | { |
533 | struct msg m; | |
3b83c932 | 534 | uint8_t *hash; |
2fe58dfd | 535 | void *hst; |
fe5e9cc4 | 536 | cstring_t err; |
2fe58dfd SE |
537 | |
538 | if (!unpick_msg(st,LABEL_MSG3,msg3,&m)) return False; | |
ff05a229 SE |
539 | if (!check_msg(st,LABEL_MSG3,&m,&err)) { |
540 | slog(st,LOG_SEC,"msg3: %s",err); | |
2fe58dfd SE |
541 | return False; |
542 | } | |
ff05a229 | 543 | |
2fe58dfd | 544 | /* Check signature and store g^x mod m */ |
3b83c932 | 545 | hash=safe_malloc(st->hash->len, "process_msg3"); |
2fe58dfd SE |
546 | hst=st->hash->init(); |
547 | st->hash->update(hst,m.hashstart,m.hashlen); | |
548 | st->hash->final(hst,hash); | |
549 | /* Terminate signature with a '0' - cheating, but should be ok */ | |
550 | m.sig[m.siglen]=0; | |
551 | if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) { | |
59635212 | 552 | slog(st,LOG_SEC,"msg3 signature failed check!"); |
3b83c932 | 553 | free(hash); |
2fe58dfd SE |
554 | return False; |
555 | } | |
3b83c932 | 556 | free(hash); |
2fe58dfd SE |
557 | |
558 | /* Terminate their DH public key with a '0' */ | |
559 | m.pk[m.pklen]=0; | |
560 | /* Invent our DH secret key */ | |
561 | st->random->generate(st->random->st,st->dh->len,st->dhsecret); | |
562 | ||
563 | /* Generate the shared key */ | |
564 | st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk, | |
7c9ca4bd | 565 | st->sharedsecret,st->sharedsecretlen); |
2fe58dfd SE |
566 | |
567 | /* Set up the transform */ | |
568 | st->new_transform->setkey(st->new_transform->st,st->sharedsecret, | |
7c9ca4bd | 569 | st->sharedsecretlen); |
2fe58dfd SE |
570 | |
571 | return True; | |
572 | } | |
573 | ||
574 | static bool_t generate_msg4(struct site *st) | |
575 | { | |
576 | /* We have both nonces, their public key and our private key. Generate | |
577 | our public key, sign it and send it to them. */ | |
578 | return generate_msg(st,LABEL_MSG4,"site:MSG4"); | |
579 | } | |
580 | ||
581 | static bool_t process_msg4(struct site *st, struct buffer_if *msg4, | |
a15faeb2 | 582 | const struct comm_addr *src) |
2fe58dfd SE |
583 | { |
584 | struct msg m; | |
3b83c932 | 585 | uint8_t *hash; |
2fe58dfd | 586 | void *hst; |
fe5e9cc4 | 587 | cstring_t err; |
2fe58dfd SE |
588 | |
589 | if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False; | |
ff05a229 SE |
590 | if (!check_msg(st,LABEL_MSG4,&m,&err)) { |
591 | slog(st,LOG_SEC,"msg4: %s",err); | |
2fe58dfd SE |
592 | return False; |
593 | } | |
594 | ||
595 | /* Check signature and store g^x mod m */ | |
3b83c932 | 596 | hash=safe_malloc(st->hash->len, "process_msg4"); |
2fe58dfd SE |
597 | hst=st->hash->init(); |
598 | st->hash->update(hst,m.hashstart,m.hashlen); | |
599 | st->hash->final(hst,hash); | |
600 | /* Terminate signature with a '0' - cheating, but should be ok */ | |
601 | m.sig[m.siglen]=0; | |
602 | if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) { | |
59635212 | 603 | slog(st,LOG_SEC,"msg4 signature failed check!"); |
3b83c932 | 604 | free(hash); |
2fe58dfd SE |
605 | return False; |
606 | } | |
3b83c932 | 607 | free(hash); |
2fe58dfd SE |
608 | |
609 | /* Terminate their DH public key with a '0' */ | |
610 | m.pk[m.pklen]=0; | |
611 | /* Generate the shared key */ | |
612 | st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk, | |
7c9ca4bd | 613 | st->sharedsecret,st->sharedsecretlen); |
2fe58dfd SE |
614 | /* Set up the transform */ |
615 | st->new_transform->setkey(st->new_transform->st,st->sharedsecret, | |
7c9ca4bd | 616 | st->sharedsecretlen); |
2fe58dfd SE |
617 | |
618 | return True; | |
619 | } | |
620 | ||
2fe58dfd SE |
621 | struct msg0 { |
622 | uint32_t dest; | |
623 | uint32_t source; | |
624 | uint32_t type; | |
625 | }; | |
626 | ||
627 | static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0, | |
628 | struct msg0 *m) | |
629 | { | |
630 | CHECK_AVAIL(msg0,4); | |
59635212 | 631 | m->dest=buf_unprepend_uint32(msg0); |
2fe58dfd | 632 | CHECK_AVAIL(msg0,4); |
59635212 | 633 | m->source=buf_unprepend_uint32(msg0); |
2fe58dfd | 634 | CHECK_AVAIL(msg0,4); |
59635212 | 635 | m->type=buf_unprepend_uint32(msg0); |
2fe58dfd SE |
636 | return True; |
637 | /* Leaves transformed part of buffer untouched */ | |
638 | } | |
639 | ||
ff05a229 SE |
640 | static bool_t generate_msg5(struct site *st) |
641 | { | |
fe5e9cc4 | 642 | cstring_t transform_err; |
ff05a229 SE |
643 | |
644 | BUF_ALLOC(&st->buffer,"site:MSG5"); | |
645 | /* We are going to add four words to the message */ | |
646 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*4)); | |
647 | /* Give the netlink code an opportunity to put its own stuff in the | |
648 | message (configuration information, etc.) */ | |
ff05a229 SE |
649 | buf_prepend_uint32(&st->buffer,LABEL_MSG5); |
650 | st->new_transform->forwards(st->new_transform->st,&st->buffer, | |
651 | &transform_err); | |
652 | buf_prepend_uint32(&st->buffer,LABEL_MSG5); | |
58650a70 | 653 | buf_prepend_uint32(&st->buffer,st->index); |
ff05a229 SE |
654 | buf_prepend_uint32(&st->buffer,st->setup_session_id); |
655 | ||
656 | st->retries=st->setup_retries; | |
657 | return True; | |
658 | } | |
659 | ||
2fe58dfd | 660 | static bool_t process_msg5(struct site *st, struct buffer_if *msg5, |
c90cc2a7 IJ |
661 | const struct comm_addr *src, |
662 | struct transform_inst_if *transform) | |
2fe58dfd SE |
663 | { |
664 | struct msg0 m; | |
fe5e9cc4 | 665 | cstring_t transform_err; |
2fe58dfd SE |
666 | |
667 | if (!unpick_msg0(st,msg5,&m)) return False; | |
668 | ||
c90cc2a7 | 669 | if (transform->reverse(transform->st,msg5,&transform_err)) { |
2fe58dfd | 670 | /* There's a problem */ |
59635212 | 671 | slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err); |
2fe58dfd SE |
672 | return False; |
673 | } | |
674 | /* Buffer should now contain untransformed PING packet data */ | |
675 | CHECK_AVAIL(msg5,4); | |
59635212 | 676 | if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) { |
ff05a229 | 677 | slog(st,LOG_SEC,"MSG5/PING packet contained wrong label"); |
2fe58dfd SE |
678 | return False; |
679 | } | |
ff7cdc9e IJ |
680 | /* Older versions of secnet used to write some config data here |
681 | * which we ignore. So we don't CHECK_EMPTY */ | |
2fe58dfd SE |
682 | return True; |
683 | } | |
684 | ||
c90cc2a7 IJ |
685 | static void create_msg6(struct site *st, struct transform_inst_if *transform, |
686 | uint32_t session_id) | |
2fe58dfd | 687 | { |
fe5e9cc4 | 688 | cstring_t transform_err; |
2fe58dfd SE |
689 | |
690 | BUF_ALLOC(&st->buffer,"site:MSG6"); | |
ff05a229 SE |
691 | /* We are going to add four words to the message */ |
692 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*4)); | |
794f2398 SE |
693 | /* Give the netlink code an opportunity to put its own stuff in the |
694 | message (configuration information, etc.) */ | |
ff05a229 | 695 | buf_prepend_uint32(&st->buffer,LABEL_MSG6); |
c90cc2a7 | 696 | transform->forwards(transform->st,&st->buffer,&transform_err); |
59635212 | 697 | buf_prepend_uint32(&st->buffer,LABEL_MSG6); |
58650a70 | 698 | buf_prepend_uint32(&st->buffer,st->index); |
c90cc2a7 IJ |
699 | buf_prepend_uint32(&st->buffer,session_id); |
700 | } | |
2fe58dfd | 701 | |
c90cc2a7 IJ |
702 | static bool_t generate_msg6(struct site *st) |
703 | { | |
704 | create_msg6(st,st->new_transform,st->setup_session_id); | |
ff05a229 | 705 | st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */ |
2fe58dfd SE |
706 | return True; |
707 | } | |
708 | ||
709 | static bool_t process_msg6(struct site *st, struct buffer_if *msg6, | |
a15faeb2 | 710 | const struct comm_addr *src) |
2fe58dfd SE |
711 | { |
712 | struct msg0 m; | |
fe5e9cc4 | 713 | cstring_t transform_err; |
2fe58dfd SE |
714 | |
715 | if (!unpick_msg0(st,msg6,&m)) return False; | |
716 | ||
717 | if (st->new_transform->reverse(st->new_transform->st, | |
718 | msg6,&transform_err)) { | |
719 | /* There's a problem */ | |
59635212 | 720 | slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err); |
2fe58dfd SE |
721 | return False; |
722 | } | |
723 | /* Buffer should now contain untransformed PING packet data */ | |
724 | CHECK_AVAIL(msg6,4); | |
59635212 SE |
725 | if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) { |
726 | slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data"); | |
2fe58dfd SE |
727 | return False; |
728 | } | |
ff7cdc9e IJ |
729 | /* Older versions of secnet used to write some config data here |
730 | * which we ignore. So we don't CHECK_EMPTY */ | |
2fe58dfd SE |
731 | return True; |
732 | } | |
733 | ||
065e1922 | 734 | static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0) |
2fe58dfd | 735 | { |
02b0959b | 736 | cstring_t transform_err, auxkey_err, newkey_err="n/a"; |
065e1922 IJ |
737 | struct msg0 m; |
738 | uint32_t problem; | |
2fe58dfd | 739 | |
2fe58dfd SE |
740 | if (!unpick_msg0(st,msg0,&m)) return False; |
741 | ||
05f39b4d IJ |
742 | /* Keep a copy so we can try decrypting it with multiple keys */ |
743 | buffer_copy(&st->scratch, msg0); | |
744 | ||
19e9a588 | 745 | problem = st->current.transform->reverse(st->current.transform->st, |
065e1922 | 746 | msg0,&transform_err); |
02b0959b | 747 | if (!problem) { |
bd98cd6b IJ |
748 | if (!st->auxiliary_is_new) |
749 | delete_one_key(st,&st->auxiliary_key, | |
750 | "peer has used new key","auxiliary key",LOG_SEC); | |
02b0959b IJ |
751 | return True; |
752 | } | |
065e1922 | 753 | |
07e4774c IJ |
754 | if (problem==2) { |
755 | slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err); | |
756 | return False; | |
757 | } | |
758 | ||
02b0959b IJ |
759 | buffer_copy(msg0, &st->scratch); |
760 | problem = st->auxiliary_key.transform->reverse | |
761 | (st->auxiliary_key.transform->st,msg0,&auxkey_err); | |
762 | if (problem==0) { | |
763 | slog(st,LOG_DROP,"processing packet which uses auxiliary key"); | |
bd98cd6b IJ |
764 | if (st->auxiliary_is_new) { |
765 | /* We previously timed out in state SENTMSG5 but it turns | |
766 | * out that our peer did in fact get our MSG5 and is | |
767 | * using the new key. So we should switch to it too. */ | |
768 | /* This is a bit like activate_new_key. */ | |
769 | struct data_key t; | |
770 | t=st->current; | |
771 | st->current=st->auxiliary_key; | |
772 | st->auxiliary_key=t; | |
773 | ||
774 | delete_one_key(st,&st->auxiliary_key,"peer has used new key", | |
775 | "previous key",LOG_SEC); | |
776 | st->auxiliary_is_new=0; | |
777 | st->renegotiate_key_time=st->auxiliary_renegotiate_key_time; | |
778 | } | |
02b0959b IJ |
779 | return True; |
780 | } | |
781 | ||
05f39b4d IJ |
782 | if (st->state==SITE_SENTMSG5) { |
783 | buffer_copy(msg0, &st->scratch); | |
784 | if (!st->new_transform->reverse(st->new_transform->st, | |
785 | msg0,&newkey_err)) { | |
786 | /* It looks like we didn't get the peer's MSG6 */ | |
787 | /* This is like a cut-down enter_new_state(SITE_RUN) */ | |
788 | slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)"); | |
789 | BUF_FREE(&st->buffer); | |
790 | st->timeout=0; | |
791 | activate_new_key(st); | |
792 | return True; /* do process the data in this packet */ | |
793 | } | |
794 | } | |
795 | ||
02b0959b IJ |
796 | slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)", |
797 | transform_err,auxkey_err,newkey_err); | |
065e1922 IJ |
798 | initiate_key_setup(st,"incoming message would not decrypt"); |
799 | return False; | |
800 | } | |
801 | ||
802 | static bool_t process_msg0(struct site *st, struct buffer_if *msg0, | |
803 | const struct comm_addr *src) | |
804 | { | |
805 | uint32_t type; | |
806 | ||
807 | if (!decrypt_msg0(st,msg0)) | |
808 | return False; | |
809 | ||
2fe58dfd | 810 | CHECK_AVAIL(msg0,4); |
59635212 | 811 | type=buf_unprepend_uint32(msg0); |
2fe58dfd | 812 | switch(type) { |
794f2398 SE |
813 | case LABEL_MSG7: |
814 | /* We must forget about the current session. */ | |
1d388569 | 815 | delete_keys(st,"request from peer",LOG_SEC); |
794f2398 | 816 | return True; |
2fe58dfd SE |
817 | case LABEL_MSG9: |
818 | /* Deliver to netlink layer */ | |
469fd1d9 | 819 | st->netlink->deliver(st->netlink->st,msg0); |
446353cd | 820 | transport_data_msgok(st,src); |
837cf01e IJ |
821 | /* See whether we should start negotiating a new key */ |
822 | if (st->now > st->renegotiate_key_time) | |
823 | initiate_key_setup(st,"incoming packet in renegotiation window"); | |
2fe58dfd | 824 | return True; |
2fe58dfd | 825 | default: |
ff05a229 SE |
826 | slog(st,LOG_SEC,"incoming encrypted message of type %08x " |
827 | "(unknown)",type); | |
2fe58dfd SE |
828 | break; |
829 | } | |
830 | return False; | |
831 | } | |
832 | ||
833 | static void dump_packet(struct site *st, struct buffer_if *buf, | |
a15faeb2 | 834 | const struct comm_addr *addr, bool_t incoming) |
2fe58dfd | 835 | { |
59635212 SE |
836 | uint32_t dest=ntohl(*(uint32_t *)buf->start); |
837 | uint32_t source=ntohl(*(uint32_t *)(buf->start+4)); | |
838 | uint32_t msgtype=ntohl(*(uint32_t *)(buf->start+8)); | |
2fe58dfd SE |
839 | |
840 | if (st->log_events & LOG_DUMP) | |
040ee979 SE |
841 | slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x:", |
842 | st->tunname,incoming?"incoming":"outgoing", | |
843 | dest,source,msgtype); | |
2fe58dfd SE |
844 | } |
845 | ||
846 | static uint32_t site_status(void *st) | |
847 | { | |
848 | return 0; | |
849 | } | |
850 | ||
851 | static bool_t send_msg(struct site *st) | |
852 | { | |
853 | if (st->retries>0) { | |
446353cd | 854 | transport_xmit(st, &st->setup_peers, &st->buffer, True); |
e7f8ec2a | 855 | st->timeout=st->now+st->setup_retry_interval; |
2fe58dfd SE |
856 | st->retries--; |
857 | return True; | |
bd98cd6b IJ |
858 | } else if (st->state==SITE_SENTMSG5) { |
859 | slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key"); | |
860 | /* We stash the key we have produced, in case it turns out that | |
861 | * our peer did see our MSG5 after all and starts using it. */ | |
862 | /* This is a bit like some of activate_new_key */ | |
863 | struct transform_inst_if *t; | |
864 | t=st->auxiliary_key.transform; | |
865 | st->auxiliary_key.transform=st->new_transform; | |
866 | st->new_transform=t; | |
867 | ||
868 | t->delkey(t->st); | |
869 | st->auxiliary_is_new=1; | |
870 | st->auxiliary_key.key_timeout=st->now+st->key_lifetime; | |
871 | st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time; | |
872 | st->auxiliary_key.remote_session_id=st->setup_session_id; | |
873 | ||
874 | enter_state_wait(st); | |
875 | return False; | |
2fe58dfd | 876 | } else { |
3454dce4 SE |
877 | slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet " |
878 | "(in state %s)",state_name(st->state)); | |
2fe58dfd SE |
879 | enter_state_wait(st); |
880 | return False; | |
881 | } | |
882 | } | |
883 | ||
884 | static void site_resolve_callback(void *sst, struct in_addr *address) | |
885 | { | |
886 | struct site *st=sst; | |
446353cd | 887 | struct comm_addr ca_buf, *ca_use; |
2fe58dfd SE |
888 | |
889 | if (st->state!=SITE_RESOLVE) { | |
890 | slog(st,LOG_UNEXPECTED,"site_resolve_callback called unexpectedly"); | |
891 | return; | |
892 | } | |
893 | if (address) { | |
446353cd | 894 | FILLZERO(ca_buf); |
59533c16 | 895 | ca_buf.comm=st->comms[0]; |
446353cd IJ |
896 | ca_buf.sin.sin_family=AF_INET; |
897 | ca_buf.sin.sin_port=htons(st->remoteport); | |
898 | ca_buf.sin.sin_addr=*address; | |
899 | ca_use=&ca_buf; | |
2fe58dfd | 900 | } else { |
2fe58dfd | 901 | slog(st,LOG_ERROR,"resolution of %s failed",st->address); |
446353cd IJ |
902 | ca_use=0; |
903 | } | |
904 | if (transport_compute_setupinit_peers(st,ca_use)) { | |
905 | enter_new_state(st,SITE_SENTMSG1); | |
906 | } else { | |
907 | /* Can't figure out who to try to to talk to */ | |
908 | slog(st,LOG_SETUP_INIT,"key exchange failed: cannot find peer address"); | |
2fe58dfd SE |
909 | enter_state_run(st); |
910 | } | |
911 | } | |
912 | ||
fe5e9cc4 | 913 | static bool_t initiate_key_setup(struct site *st, cstring_t reason) |
9d3a4132 SE |
914 | { |
915 | if (st->state!=SITE_RUN) return False; | |
794f2398 | 916 | slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason); |
9d3a4132 | 917 | if (st->address) { |
794f2398 | 918 | slog(st,LOG_SETUP_INIT,"resolving peer address"); |
9d3a4132 | 919 | return enter_state_resolve(st); |
446353cd | 920 | } else if (transport_compute_setupinit_peers(st,0)) { |
ff05a229 | 921 | return enter_new_state(st,SITE_SENTMSG1); |
9d3a4132 | 922 | } |
ff05a229 | 923 | slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer"); |
9d3a4132 SE |
924 | return False; |
925 | } | |
926 | ||
2fe58dfd SE |
927 | static void activate_new_key(struct site *st) |
928 | { | |
929 | struct transform_inst_if *t; | |
930 | ||
02b0959b IJ |
931 | /* We have three transform instances, which we swap between old, |
932 | active and setup */ | |
933 | t=st->auxiliary_key.transform; | |
934 | st->auxiliary_key.transform=st->current.transform; | |
19e9a588 | 935 | st->current.transform=st->new_transform; |
2fe58dfd SE |
936 | st->new_transform=t; |
937 | ||
938 | t->delkey(t->st); | |
2fe58dfd | 939 | st->timeout=0; |
bd98cd6b | 940 | st->auxiliary_is_new=0; |
02b0959b | 941 | st->auxiliary_key.key_timeout=st->current.key_timeout; |
19e9a588 | 942 | st->current.key_timeout=st->now+st->key_lifetime; |
ff05a229 | 943 | st->renegotiate_key_time=st->now+st->key_renegotiate_time; |
446353cd | 944 | transport_peers_copy(st,&st->peers,&st->setup_peers); |
19e9a588 | 945 | st->current.remote_session_id=st->setup_session_id; |
2fe58dfd SE |
946 | |
947 | slog(st,LOG_ACTIVATE_KEY,"new key activated"); | |
9d3a4132 | 948 | enter_state_run(st); |
2fe58dfd SE |
949 | } |
950 | ||
1d388569 IJ |
951 | static void delete_one_key(struct site *st, struct data_key *key, |
952 | cstring_t reason, cstring_t which, uint32_t loglevel) | |
953 | { | |
954 | if (!key->transform->valid(key->transform->st)) return; | |
955 | if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason); | |
956 | key->transform->delkey(key->transform->st); | |
957 | key->key_timeout=0; | |
958 | } | |
959 | ||
960 | static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel) | |
794f2398 | 961 | { |
3d8d8f4e | 962 | if (current_valid(st)) { |
794f2398 SE |
963 | slog(st,loglevel,"session closed (%s)",reason); |
964 | ||
1d388569 | 965 | delete_one_key(st,&st->current,0,0,0); |
794f2398 SE |
966 | set_link_quality(st); |
967 | } | |
02b0959b | 968 | delete_one_key(st,&st->auxiliary_key,0,0,0); |
794f2398 SE |
969 | } |
970 | ||
2fe58dfd SE |
971 | static void state_assert(struct site *st, bool_t ok) |
972 | { | |
4f5e39ec | 973 | if (!ok) fatal("site:state_assert"); |
2fe58dfd SE |
974 | } |
975 | ||
976 | static void enter_state_stop(struct site *st) | |
977 | { | |
978 | st->state=SITE_STOP; | |
979 | st->timeout=0; | |
1d388569 | 980 | delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY); |
2fe58dfd SE |
981 | st->new_transform->delkey(st->new_transform->st); |
982 | } | |
983 | ||
9d3a4132 SE |
984 | static void set_link_quality(struct site *st) |
985 | { | |
986 | uint32_t quality; | |
3d8d8f4e | 987 | if (current_valid(st)) |
9d3a4132 SE |
988 | quality=LINK_QUALITY_UP; |
989 | else if (st->state==SITE_WAIT || st->state==SITE_STOP) | |
990 | quality=LINK_QUALITY_DOWN; | |
991 | else if (st->address) | |
992 | quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS; | |
446353cd | 993 | else if (transport_peers_valid(&st->peers)) |
9d3a4132 SE |
994 | quality=LINK_QUALITY_DOWN_STALE_ADDRESS; |
995 | else | |
996 | quality=LINK_QUALITY_DOWN; | |
997 | ||
469fd1d9 | 998 | st->netlink->set_quality(st->netlink->st,quality); |
9d3a4132 SE |
999 | } |
1000 | ||
2fe58dfd SE |
1001 | static void enter_state_run(struct site *st) |
1002 | { | |
1003 | slog(st,LOG_STATE,"entering state RUN"); | |
1004 | st->state=SITE_RUN; | |
1005 | st->timeout=0; | |
9d3a4132 | 1006 | |
ff05a229 | 1007 | st->setup_session_id=0; |
446353cd | 1008 | transport_peers_clear(st,&st->setup_peers); |
ff05a229 SE |
1009 | memset(st->localN,0,NONCELEN); |
1010 | memset(st->remoteN,0,NONCELEN); | |
1011 | st->new_transform->delkey(st->new_transform->st); | |
1012 | memset(st->dhsecret,0,st->dh->len); | |
7c9ca4bd | 1013 | memset(st->sharedsecret,0,st->sharedsecretlen); |
9d3a4132 | 1014 | set_link_quality(st); |
2fe58dfd SE |
1015 | } |
1016 | ||
1017 | static bool_t enter_state_resolve(struct site *st) | |
1018 | { | |
1019 | state_assert(st,st->state==SITE_RUN); | |
1020 | slog(st,LOG_STATE,"entering state RESOLVE"); | |
1021 | st->state=SITE_RESOLVE; | |
1022 | st->resolver->request(st->resolver->st,st->address, | |
1023 | site_resolve_callback,st); | |
1024 | return True; | |
1025 | } | |
1026 | ||
ff05a229 | 1027 | static bool_t enter_new_state(struct site *st, uint32_t next) |
2fe58dfd | 1028 | { |
ff05a229 | 1029 | bool_t (*gen)(struct site *st); |
3b83c932 SE |
1030 | int r; |
1031 | ||
ff05a229 SE |
1032 | slog(st,LOG_STATE,"entering state %s",state_name(next)); |
1033 | switch(next) { | |
1034 | case SITE_SENTMSG1: | |
1035 | state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE); | |
1036 | gen=generate_msg1; | |
1037 | break; | |
1038 | case SITE_SENTMSG2: | |
1039 | state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE || | |
1040 | st->state==SITE_SENTMSG1 || st->state==SITE_WAIT); | |
1041 | gen=generate_msg2; | |
1042 | break; | |
1043 | case SITE_SENTMSG3: | |
1044 | state_assert(st,st->state==SITE_SENTMSG1); | |
1045 | BUF_FREE(&st->buffer); | |
1046 | gen=generate_msg3; | |
1047 | break; | |
1048 | case SITE_SENTMSG4: | |
1049 | state_assert(st,st->state==SITE_SENTMSG2); | |
1050 | BUF_FREE(&st->buffer); | |
1051 | gen=generate_msg4; | |
1052 | break; | |
1053 | case SITE_SENTMSG5: | |
1054 | state_assert(st,st->state==SITE_SENTMSG3); | |
1055 | BUF_FREE(&st->buffer); | |
1056 | gen=generate_msg5; | |
1057 | break; | |
1058 | case SITE_RUN: | |
1059 | state_assert(st,st->state==SITE_SENTMSG4); | |
1060 | BUF_FREE(&st->buffer); | |
1061 | gen=generate_msg6; | |
1062 | break; | |
1063 | default: | |
1064 | gen=NULL; | |
4f5e39ec | 1065 | fatal("enter_new_state(%s): invalid new state",state_name(next)); |
ff05a229 | 1066 | break; |
2fe58dfd | 1067 | } |
2fe58dfd | 1068 | |
3b83c932 SE |
1069 | if (hacky_par_start_failnow()) return False; |
1070 | ||
1071 | r= gen(st) && send_msg(st); | |
1072 | ||
1073 | hacky_par_end(&r, | |
e7f8ec2a | 1074 | st->setup_retries, st->setup_retry_interval, |
3b83c932 SE |
1075 | send_msg, st); |
1076 | ||
1077 | if (r) { | |
ff05a229 SE |
1078 | st->state=next; |
1079 | if (next==SITE_RUN) { | |
1080 | BUF_FREE(&st->buffer); /* Never reused */ | |
1081 | st->timeout=0; /* Never retransmit */ | |
1082 | activate_new_key(st); | |
1083 | } | |
2fe58dfd SE |
1084 | return True; |
1085 | } | |
ff05a229 SE |
1086 | slog(st,LOG_ERROR,"error entering state %s",state_name(next)); |
1087 | st->buffer.free=False; /* Unconditionally use the buffer; it may be | |
1088 | in either state, and enter_state_wait() will | |
1089 | do a BUF_FREE() */ | |
2fe58dfd SE |
1090 | enter_state_wait(st); |
1091 | return False; | |
1092 | } | |
1093 | ||
ff05a229 | 1094 | /* msg7 tells our peer that we're about to forget our key */ |
fe5e9cc4 | 1095 | static bool_t send_msg7(struct site *st, cstring_t reason) |
794f2398 | 1096 | { |
fe5e9cc4 | 1097 | cstring_t transform_err; |
794f2398 | 1098 | |
3d8d8f4e | 1099 | if (current_valid(st) && st->buffer.free |
446353cd | 1100 | && transport_peers_valid(&st->peers)) { |
794f2398 SE |
1101 | BUF_ALLOC(&st->buffer,"site:MSG7"); |
1102 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*3)); | |
1103 | buf_append_uint32(&st->buffer,LABEL_MSG7); | |
1104 | buf_append_string(&st->buffer,reason); | |
19e9a588 | 1105 | st->current.transform->forwards(st->current.transform->st, |
794f2398 SE |
1106 | &st->buffer, &transform_err); |
1107 | buf_prepend_uint32(&st->buffer,LABEL_MSG0); | |
58650a70 | 1108 | buf_prepend_uint32(&st->buffer,st->index); |
19e9a588 | 1109 | buf_prepend_uint32(&st->buffer,st->current.remote_session_id); |
446353cd | 1110 | transport_xmit(st,&st->peers,&st->buffer,True); |
794f2398 SE |
1111 | BUF_FREE(&st->buffer); |
1112 | return True; | |
1113 | } | |
1114 | return False; | |
1115 | } | |
1116 | ||
2fe58dfd SE |
1117 | /* We go into this state if our peer becomes uncommunicative. Similar to |
1118 | the "stop" state, we forget all session keys for a while, before | |
1119 | re-entering the "run" state. */ | |
1120 | static void enter_state_wait(struct site *st) | |
1121 | { | |
1122 | slog(st,LOG_STATE,"entering state WAIT"); | |
1123 | st->timeout=st->now+st->wait_timeout; | |
1124 | st->state=SITE_WAIT; | |
9d3a4132 | 1125 | set_link_quality(st); |
2fe58dfd SE |
1126 | BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */ |
1127 | /* XXX Erase keys etc. */ | |
1128 | } | |
1129 | ||
16f73fa6 | 1130 | static inline void site_settimeout(uint64_t timeout, int *timeout_io) |
fe5e9cc4 SE |
1131 | { |
1132 | if (timeout) { | |
0009e60a IJ |
1133 | int64_t offset=timeout-*now; |
1134 | if (offset<0) offset=0; | |
fe5e9cc4 SE |
1135 | if (offset>INT_MAX) offset=INT_MAX; |
1136 | if (*timeout_io<0 || offset<*timeout_io) | |
1137 | *timeout_io=offset; | |
1138 | } | |
1139 | } | |
1140 | ||
2fe58dfd | 1141 | static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io, |
90a39563 | 1142 | int *timeout_io) |
2fe58dfd SE |
1143 | { |
1144 | struct site *st=sst; | |
1145 | ||
1146 | *nfds_io=0; /* We don't use any file descriptors */ | |
1147 | st->now=*now; | |
1148 | ||
1149 | /* Work out when our next timeout is. The earlier of 'timeout' or | |
19e9a588 | 1150 | 'current.key_timeout'. A stored value of '0' indicates no timeout |
2fe58dfd | 1151 | active. */ |
16f73fa6 | 1152 | site_settimeout(st->timeout, timeout_io); |
19e9a588 | 1153 | site_settimeout(st->current.key_timeout, timeout_io); |
02b0959b | 1154 | site_settimeout(st->auxiliary_key.key_timeout, timeout_io); |
2fe58dfd SE |
1155 | |
1156 | return 0; /* success */ | |
1157 | } | |
1158 | ||
1d388569 IJ |
1159 | static void check_expiry(struct site *st, struct data_key *key, |
1160 | const char *which) | |
1161 | { | |
1162 | if (key->key_timeout && *now>key->key_timeout) { | |
1163 | delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY); | |
1164 | } | |
1165 | } | |
1166 | ||
2fe58dfd | 1167 | /* NB site_afterpoll will be called before site_beforepoll is ever called */ |
90a39563 | 1168 | static void site_afterpoll(void *sst, struct pollfd *fds, int nfds) |
2fe58dfd SE |
1169 | { |
1170 | struct site *st=sst; | |
1171 | ||
1172 | st->now=*now; | |
1173 | if (st->timeout && *now>st->timeout) { | |
2fe58dfd | 1174 | st->timeout=0; |
3b83c932 SE |
1175 | if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) { |
1176 | if (!hacky_par_start_failnow()) | |
1177 | send_msg(st); | |
1178 | } else if (st->state==SITE_WAIT) { | |
2fe58dfd SE |
1179 | enter_state_run(st); |
1180 | } else { | |
1181 | slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d", | |
1182 | st->state); | |
1183 | } | |
1184 | } | |
1d388569 | 1185 | check_expiry(st,&st->current,"current key"); |
02b0959b | 1186 | check_expiry(st,&st->auxiliary_key,"auxiliary key"); |
2fe58dfd SE |
1187 | } |
1188 | ||
1189 | /* This function is called by the netlink device to deliver packets | |
1190 | intended for the remote network. The packet is in "raw" wire | |
1191 | format, but is guaranteed to be word-aligned. */ | |
469fd1d9 | 1192 | static void site_outgoing(void *sst, struct buffer_if *buf) |
2fe58dfd SE |
1193 | { |
1194 | struct site *st=sst; | |
fe5e9cc4 | 1195 | cstring_t transform_err; |
2fe58dfd SE |
1196 | |
1197 | if (st->state==SITE_STOP) { | |
1198 | BUF_FREE(buf); | |
1199 | return; | |
1200 | } | |
1201 | ||
1202 | /* In all other states we consider delivering the packet if we have | |
1203 | a valid key and a valid address to send it to. */ | |
3d8d8f4e | 1204 | if (current_valid(st) && transport_peers_valid(&st->peers)) { |
2fe58dfd | 1205 | /* Transform it and send it */ |
70dc107b SE |
1206 | if (buf->size>0) { |
1207 | buf_prepend_uint32(buf,LABEL_MSG9); | |
19e9a588 | 1208 | st->current.transform->forwards(st->current.transform->st, |
70dc107b SE |
1209 | buf, &transform_err); |
1210 | buf_prepend_uint32(buf,LABEL_MSG0); | |
58650a70 | 1211 | buf_prepend_uint32(buf,st->index); |
19e9a588 | 1212 | buf_prepend_uint32(buf,st->current.remote_session_id); |
446353cd | 1213 | transport_xmit(st,&st->peers,buf,False); |
70dc107b | 1214 | } |
2fe58dfd SE |
1215 | BUF_FREE(buf); |
1216 | return; | |
1217 | } | |
1218 | ||
70dc107b | 1219 | slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size); |
2fe58dfd | 1220 | BUF_FREE(buf); |
794f2398 | 1221 | initiate_key_setup(st,"outgoing packet"); |
2fe58dfd SE |
1222 | } |
1223 | ||
1224 | /* This function is called by the communication device to deliver | |
1225 | packets from our peers. */ | |
1226 | static bool_t site_incoming(void *sst, struct buffer_if *buf, | |
a15faeb2 | 1227 | const struct comm_addr *source) |
2fe58dfd SE |
1228 | { |
1229 | struct site *st=sst; | |
20138876 IJ |
1230 | |
1231 | if (buf->size < 12) return False; | |
1232 | ||
59635212 | 1233 | uint32_t dest=ntohl(*(uint32_t *)buf->start); |
2fe58dfd SE |
1234 | |
1235 | if (dest==0) { | |
2fe58dfd SE |
1236 | /* It could be for any site - it should have LABEL_MSG1 and |
1237 | might have our name and our peer's name in it */ | |
ff05a229 | 1238 | if (buf->size<(st->setupsiglen+8+NONCELEN)) return False; |
2fe58dfd | 1239 | if (memcmp(buf->start+8,st->setupsig,st->setupsiglen)==0) { |
2fe58dfd | 1240 | /* It's addressed to us. Decide what to do about it. */ |
ff05a229 | 1241 | dump_packet(st,buf,source,True); |
2fe58dfd SE |
1242 | if (st->state==SITE_RUN || st->state==SITE_RESOLVE || |
1243 | st->state==SITE_WAIT) { | |
1244 | /* We should definitely process it */ | |
1245 | if (process_msg1(st,buf,source)) { | |
1246 | slog(st,LOG_SETUP_INIT,"key setup initiated by peer"); | |
ff05a229 | 1247 | enter_new_state(st,SITE_SENTMSG2); |
2fe58dfd SE |
1248 | } else { |
1249 | slog(st,LOG_ERROR,"failed to process incoming msg1"); | |
1250 | } | |
1251 | BUF_FREE(buf); | |
1252 | return True; | |
ff05a229 | 1253 | } else if (st->state==SITE_SENTMSG1) { |
2fe58dfd SE |
1254 | /* We've just sent a message 1! They may have crossed on |
1255 | the wire. If we have priority then we ignore the | |
1256 | incoming one, otherwise we process it as usual. */ | |
1257 | if (st->setup_priority) { | |
1258 | BUF_FREE(buf); | |
1259 | slog(st,LOG_DUMP,"crossed msg1s; we are higher " | |
1260 | "priority => ignore incoming msg1"); | |
1261 | return True; | |
1262 | } else { | |
1263 | slog(st,LOG_DUMP,"crossed msg1s; we are lower " | |
1264 | "priority => use incoming msg1"); | |
1265 | if (process_msg1(st,buf,source)) { | |
1266 | BUF_FREE(&st->buffer); /* Free our old message 1 */ | |
ff05a229 | 1267 | enter_new_state(st,SITE_SENTMSG2); |
2fe58dfd SE |
1268 | } else { |
1269 | slog(st,LOG_ERROR,"failed to process an incoming " | |
1270 | "crossed msg1 (we have low priority)"); | |
1271 | } | |
1272 | BUF_FREE(buf); | |
1273 | return True; | |
1274 | } | |
1275 | } | |
1276 | /* The message 1 was received at an unexpected stage of the | |
1277 | key setup. XXX POLICY - what do we do? */ | |
1278 | slog(st,LOG_UNEXPECTED,"unexpected incoming message 1"); | |
1279 | BUF_FREE(buf); | |
1280 | return True; | |
1281 | } | |
1282 | return False; /* Not for us. */ | |
1283 | } | |
58650a70 | 1284 | if (dest==st->index) { |
2fe58dfd | 1285 | /* Explicitly addressed to us */ |
ff05a229 | 1286 | uint32_t msgtype=ntohl(get_uint32(buf->start+8)); |
2fe58dfd SE |
1287 | if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True); |
1288 | switch (msgtype) { | |
794f2398 SE |
1289 | case 0: /* NAK */ |
1290 | /* If the source is our current peer then initiate a key setup, | |
1291 | because our peer's forgotten the key */ | |
19e9a588 | 1292 | if (get_uint32(buf->start+4)==st->current.remote_session_id) { |
794f2398 SE |
1293 | initiate_key_setup(st,"received a NAK"); |
1294 | } else { | |
1295 | slog(st,LOG_SEC,"bad incoming NAK"); | |
1296 | } | |
1297 | break; | |
2fe58dfd SE |
1298 | case LABEL_MSG0: |
1299 | process_msg0(st,buf,source); | |
1300 | break; | |
1301 | case LABEL_MSG1: | |
1302 | /* Setup packet: should not have been explicitly addressed | |
1303 | to us */ | |
59635212 | 1304 | slog(st,LOG_SEC,"incoming explicitly addressed msg1"); |
2fe58dfd SE |
1305 | break; |
1306 | case LABEL_MSG2: | |
1307 | /* Setup packet: expected only in state SENTMSG1 */ | |
1308 | if (st->state!=SITE_SENTMSG1) { | |
1309 | slog(st,LOG_UNEXPECTED,"unexpected MSG2"); | |
446353cd IJ |
1310 | } else if (process_msg2(st,buf,source)) { |
1311 | transport_setup_msgok(st,source); | |
ff05a229 | 1312 | enter_new_state(st,SITE_SENTMSG3); |
446353cd | 1313 | } else { |
59635212 | 1314 | slog(st,LOG_SEC,"invalid MSG2"); |
2fe58dfd SE |
1315 | } |
1316 | break; | |
1317 | case LABEL_MSG3: | |
1318 | /* Setup packet: expected only in state SENTMSG2 */ | |
1319 | if (st->state!=SITE_SENTMSG2) { | |
1320 | slog(st,LOG_UNEXPECTED,"unexpected MSG3"); | |
446353cd IJ |
1321 | } else if (process_msg3(st,buf,source)) { |
1322 | transport_setup_msgok(st,source); | |
ff05a229 | 1323 | enter_new_state(st,SITE_SENTMSG4); |
446353cd | 1324 | } else { |
59635212 | 1325 | slog(st,LOG_SEC,"invalid MSG3"); |
2fe58dfd SE |
1326 | } |
1327 | break; | |
1328 | case LABEL_MSG4: | |
1329 | /* Setup packet: expected only in state SENTMSG3 */ | |
1330 | if (st->state!=SITE_SENTMSG3) { | |
1331 | slog(st,LOG_UNEXPECTED,"unexpected MSG4"); | |
446353cd IJ |
1332 | } else if (process_msg4(st,buf,source)) { |
1333 | transport_setup_msgok(st,source); | |
ff05a229 | 1334 | enter_new_state(st,SITE_SENTMSG5); |
446353cd | 1335 | } else { |
59635212 | 1336 | slog(st,LOG_SEC,"invalid MSG4"); |
2fe58dfd SE |
1337 | } |
1338 | break; | |
1339 | case LABEL_MSG5: | |
4efd681a SE |
1340 | /* Setup packet: expected only in state SENTMSG4 */ |
1341 | /* (may turn up in state RUN if our return MSG6 was lost | |
1342 | and the new key has already been activated. In that | |
05f39b4d IJ |
1343 | case we discard it. The peer will realise that we |
1344 | are using the new key when they see our data packets. | |
1345 | Until then the peer's data packets to us get discarded. */ | |
c90cc2a7 IJ |
1346 | if (st->state==SITE_SENTMSG4) { |
1347 | if (process_msg5(st,buf,source,st->new_transform)) { | |
1348 | transport_setup_msgok(st,source); | |
1349 | enter_new_state(st,SITE_RUN); | |
1350 | } else { | |
1351 | slog(st,LOG_SEC,"invalid MSG5"); | |
1352 | } | |
1353 | } else if (st->state==SITE_RUN) { | |
19e9a588 | 1354 | if (process_msg5(st,buf,source,st->current.transform)) { |
c90cc2a7 IJ |
1355 | slog(st,LOG_DROP,"got MSG5, retransmitting MSG6"); |
1356 | transport_setup_msgok(st,source); | |
19e9a588 IJ |
1357 | create_msg6(st,st->current.transform, |
1358 | st->current.remote_session_id); | |
c90cc2a7 IJ |
1359 | transport_xmit(st,&st->peers,&st->buffer,True); |
1360 | BUF_FREE(&st->buffer); | |
1361 | } else { | |
1362 | slog(st,LOG_SEC,"invalid MSG5 (in state RUN)"); | |
1363 | } | |
2fe58dfd | 1364 | } else { |
c90cc2a7 | 1365 | slog(st,LOG_UNEXPECTED,"unexpected MSG5"); |
2fe58dfd SE |
1366 | } |
1367 | break; | |
1368 | case LABEL_MSG6: | |
1369 | /* Setup packet: expected only in state SENTMSG5 */ | |
1370 | if (st->state!=SITE_SENTMSG5) { | |
1371 | slog(st,LOG_UNEXPECTED,"unexpected MSG6"); | |
1372 | } else if (process_msg6(st,buf,source)) { | |
1373 | BUF_FREE(&st->buffer); /* Free message 5 */ | |
446353cd | 1374 | transport_setup_msgok(st,source); |
2fe58dfd SE |
1375 | activate_new_key(st); |
1376 | } else { | |
59635212 | 1377 | slog(st,LOG_SEC,"invalid MSG6"); |
2fe58dfd SE |
1378 | } |
1379 | break; | |
2fe58dfd | 1380 | default: |
59635212 | 1381 | slog(st,LOG_SEC,"received message of unknown type 0x%08x", |
2fe58dfd SE |
1382 | msgtype); |
1383 | break; | |
1384 | } | |
1385 | BUF_FREE(buf); | |
1386 | return True; | |
1387 | } | |
1388 | ||
1389 | return False; | |
1390 | } | |
1391 | ||
1392 | static void site_control(void *vst, bool_t run) | |
1393 | { | |
1394 | struct site *st=vst; | |
1395 | if (run) enter_state_run(st); | |
1396 | else enter_state_stop(st); | |
1397 | } | |
1398 | ||
794f2398 SE |
1399 | static void site_phase_hook(void *sst, uint32_t newphase) |
1400 | { | |
1401 | struct site *st=sst; | |
1402 | ||
1403 | /* The program is shutting down; tell our peer */ | |
1404 | send_msg7(st,"shutting down"); | |
1405 | } | |
1406 | ||
2fe58dfd SE |
1407 | static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context, |
1408 | list_t *args) | |
1409 | { | |
58650a70 | 1410 | static uint32_t index_sequence; |
2fe58dfd SE |
1411 | struct site *st; |
1412 | item_t *item; | |
1413 | dict_t *dict; | |
59533c16 | 1414 | int i; |
2fe58dfd SE |
1415 | |
1416 | st=safe_malloc(sizeof(*st),"site_apply"); | |
1417 | ||
1418 | st->cl.description="site"; | |
1419 | st->cl.type=CL_SITE; | |
1420 | st->cl.apply=NULL; | |
1421 | st->cl.interface=&st->ops; | |
1422 | st->ops.st=st; | |
1423 | st->ops.control=site_control; | |
1424 | st->ops.status=site_status; | |
1425 | ||
1426 | /* First parameter must be a dict */ | |
1427 | item=list_elem(args,0); | |
1428 | if (!item || item->type!=t_dict) | |
1429 | cfgfatal(loc,"site","parameter must be a dictionary\n"); | |
1430 | ||
1431 | dict=item->data.dict; | |
558fa3fb SE |
1432 | st->localname=dict_read_string(dict, "local-name", True, "site", loc); |
1433 | st->remotename=dict_read_string(dict, "name", True, "site", loc); | |
dba19f84 IJ |
1434 | |
1435 | st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False); | |
1436 | bool_t local_mobile= | |
1437 | dict_read_bool(dict,"local-mobile",False,"site",loc,False); | |
1438 | ||
558fa3fb SE |
1439 | /* Sanity check (which also allows the 'sites' file to include |
1440 | site() closures for all sites including our own): refuse to | |
1441 | talk to ourselves */ | |
1442 | if (strcmp(st->localname,st->remotename)==0) { | |
b2a56f7c | 1443 | Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n", |
baa06aeb | 1444 | st->localname); |
dba19f84 IJ |
1445 | if (st->peer_mobile != local_mobile) |
1446 | cfgfatal(loc,"site","site %s's peer-mobile=%d" | |
1447 | " but our local-mobile=%d\n", | |
1448 | st->localname, st->peer_mobile, local_mobile); | |
1449 | free(st); | |
1450 | return NULL; | |
1451 | } | |
1452 | if (st->peer_mobile && local_mobile) { | |
1453 | Message(M_WARNING,"site %s: site is mobile but so are we" | |
1454 | " -> ignoring this site\n", st->remotename); | |
558fa3fb SE |
1455 | free(st); |
1456 | return NULL; | |
1457 | } | |
dba19f84 | 1458 | |
58650a70 RK |
1459 | assert(index_sequence < 0xffffffffUL); |
1460 | st->index = ++index_sequence; | |
469fd1d9 | 1461 | st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc); |
59533c16 IJ |
1462 | |
1463 | list_t *comms_cfg=dict_lookup(dict,"comm"); | |
39a6b1e2 | 1464 | if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n"); |
59533c16 IJ |
1465 | st->ncomms=list_length(comms_cfg); |
1466 | st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms"); | |
1467 | assert(st->ncomms); | |
1468 | for (i=0; i<st->ncomms; i++) { | |
1469 | item_t *item=list_elem(comms_cfg,i); | |
39a6b1e2 IJ |
1470 | if (item->type!=t_closure) |
1471 | cfgfatal(loc,"site","comm is not a closure\n"); | |
59533c16 | 1472 | closure_t *cl=item->data.closure; |
39a6b1e2 | 1473 | if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n"); |
59533c16 IJ |
1474 | st->comms[i]=cl->interface; |
1475 | } | |
1476 | ||
2fe58dfd SE |
1477 | st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc); |
1478 | st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc); | |
1479 | st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc); | |
1480 | ||
2fe58dfd | 1481 | st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc); |
2fe58dfd | 1482 | st->address=dict_read_string(dict, "address", False, "site", loc); |
3454dce4 SE |
1483 | if (st->address) |
1484 | st->remoteport=dict_read_number(dict,"port",True,"site",loc,0); | |
1485 | else st->remoteport=0; | |
2fe58dfd SE |
1486 | st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc); |
1487 | ||
1488 | st->transform= | |
1489 | find_cl_if(dict,"transform",CL_TRANSFORM,True,"site",loc); | |
1490 | ||
1491 | st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc); | |
1492 | st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc); | |
1493 | ||
e57264d6 IJ |
1494 | #define DEFAULT(D) (st->peer_mobile || local_mobile \ |
1495 | ? DEFAULT_MOBILE_##D : DEFAULT_##D) | |
e7f8ec2a | 1496 | #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D)); |
c27ca22f | 1497 | |
e7f8ec2a IJ |
1498 | st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME); |
1499 | st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES); | |
1500 | st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL); | |
1501 | st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME); | |
1502 | ||
446353cd IJ |
1503 | st->mobile_peer_expiry= dict_read_number( |
1504 | dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY); | |
1505 | ||
1506 | st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number( | |
1507 | dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX); | |
1508 | if (st->transport_peers_max<1 || | |
1509 | st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) { | |
1510 | cfgfatal(loc,"site","mobile-peers-max must be in range 1.." | |
1511 | STRING(MAX_MOBILE_PEERS_MAX) "\n"); | |
1512 | } | |
1513 | ||
e7f8ec2a | 1514 | if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2) |
c27ca22f IJ |
1515 | st->key_renegotiate_time=st->key_lifetime/2; |
1516 | else | |
e7f8ec2a | 1517 | st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP); |
9d3a4132 | 1518 | st->key_renegotiate_time=dict_read_number( |
cce0051f | 1519 | dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time); |
9d3a4132 SE |
1520 | if (st->key_renegotiate_time > st->key_lifetime) { |
1521 | cfgfatal(loc,"site", | |
1522 | "renegotiate-time must be less than key-lifetime\n"); | |
1523 | } | |
9d3a4132 SE |
1524 | |
1525 | st->log_events=string_list_to_word(dict_lookup(dict,"log-events"), | |
1526 | log_event_table,"site"); | |
2fe58dfd | 1527 | |
4efd681a SE |
1528 | st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5, |
1529 | "site_apply"); | |
1530 | sprintf(st->tunname,"%s<->%s",st->localname,st->remotename); | |
1531 | ||
2fe58dfd | 1532 | /* The information we expect to see in incoming messages of type 1 */ |
59230b9b IJ |
1533 | /* fixme: lots of unchecked overflows here, but the results are only |
1534 | corrupted packets rather than undefined behaviour */ | |
2fe58dfd SE |
1535 | st->setupsiglen=strlen(st->remotename)+strlen(st->localname)+8; |
1536 | st->setupsig=safe_malloc(st->setupsiglen,"site_apply"); | |
8689b3a9 SE |
1537 | put_uint32(st->setupsig+0,LABEL_MSG1); |
1538 | put_uint16(st->setupsig+4,strlen(st->remotename)); | |
2fe58dfd | 1539 | memcpy(&st->setupsig[6],st->remotename,strlen(st->remotename)); |
8689b3a9 | 1540 | put_uint16(st->setupsig+(6+strlen(st->remotename)),strlen(st->localname)); |
2fe58dfd SE |
1541 | memcpy(&st->setupsig[8+strlen(st->remotename)],st->localname, |
1542 | strlen(st->localname)); | |
1543 | st->setup_priority=(strcmp(st->localname,st->remotename)>0); | |
1544 | ||
1545 | buffer_new(&st->buffer,SETUP_BUFFER_LEN); | |
1546 | ||
05f39b4d IJ |
1547 | buffer_new(&st->scratch,0); |
1548 | BUF_ALLOC(&st->scratch,"site:scratch"); | |
1549 | ||
2fe58dfd SE |
1550 | /* We are interested in poll(), but only for timeouts. We don't have |
1551 | any fds of our own. */ | |
1552 | register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site"); | |
1553 | st->timeout=0; | |
1554 | ||
19e9a588 | 1555 | st->current.key_timeout=0; |
02b0959b | 1556 | st->auxiliary_key.key_timeout=0; |
446353cd IJ |
1557 | transport_peers_clear(st,&st->peers); |
1558 | transport_peers_clear(st,&st->setup_peers); | |
2fe58dfd SE |
1559 | /* XXX mlock these */ |
1560 | st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret"); | |
7c9ca4bd IJ |
1561 | st->sharedsecretlen=st->transform->keylen?:st->dh->ceil_len; |
1562 | st->sharedsecret=safe_malloc(st->sharedsecretlen,"site:sharedsecret"); | |
2fe58dfd | 1563 | |
59533c16 IJ |
1564 | /* We need to compute some properties of our comms */ |
1565 | #define COMPUTE_WORST(pad) \ | |
1566 | int worst_##pad=0; \ | |
1567 | for (i=0; i<st->ncomms; i++) { \ | |
1568 | int thispad=st->comms[i]->pad; \ | |
1569 | if (thispad > worst_##pad) \ | |
1570 | worst_##pad=thispad; \ | |
1571 | } | |
1572 | COMPUTE_WORST(min_start_pad) | |
1573 | COMPUTE_WORST(min_end_pad) | |
1574 | ||
2fe58dfd | 1575 | /* We need to register the remote networks with the netlink device */ |
469fd1d9 | 1576 | st->netlink->reg(st->netlink->st, site_outgoing, st, |
ff05a229 | 1577 | st->transform->max_start_pad+(4*4)+ |
59533c16 IJ |
1578 | worst_min_start_pad, |
1579 | st->transform->max_end_pad+worst_min_end_pad); | |
ff05a229 | 1580 | |
59533c16 IJ |
1581 | for (i=0; i<st->ncomms; i++) |
1582 | st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming); | |
2fe58dfd | 1583 | |
19e9a588 | 1584 | st->current.transform=st->transform->create(st->transform->st); |
02b0959b | 1585 | st->auxiliary_key.transform=st->transform->create(st->transform->st); |
2fe58dfd | 1586 | st->new_transform=st->transform->create(st->transform->st); |
bd98cd6b | 1587 | st->auxiliary_is_new=0; |
2fe58dfd SE |
1588 | |
1589 | enter_state_stop(st); | |
1590 | ||
794f2398 SE |
1591 | add_hook(PHASE_SHUTDOWN,site_phase_hook,st); |
1592 | ||
2fe58dfd SE |
1593 | return new_closure(&st->cl); |
1594 | } | |
1595 | ||
2fe58dfd SE |
1596 | void site_module(dict_t *dict) |
1597 | { | |
1598 | add_closure(dict,"site",site_apply); | |
1599 | } | |
446353cd IJ |
1600 | |
1601 | ||
1602 | /***** TRANSPORT PEERS definitions *****/ | |
1603 | ||
1604 | static void transport_peers_debug(struct site *st, transport_peers *dst, | |
1605 | const char *didwhat, | |
1606 | int nargs, const struct comm_addr *args, | |
1607 | size_t stride) { | |
1608 | int i; | |
1609 | char *argp; | |
1610 | ||
1611 | if (!(st->log_events & LOG_PEER_ADDRS)) | |
1612 | return; /* an optimisation */ | |
1613 | ||
1614 | slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d", | |
1615 | (dst==&st->peers ? "data" : | |
1616 | dst==&st->setup_peers ? "setup" : "UNKNOWN"), | |
1617 | didwhat, nargs, dst->npeers); | |
1618 | ||
1619 | for (i=0, argp=(void*)args; | |
1620 | i<nargs; | |
1621 | i++, (argp+=stride?stride:sizeof(*args))) { | |
1622 | const struct comm_addr *ca=(void*)argp; | |
1623 | slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s", | |
1624 | i, ca->comm->addr_to_string(ca->comm->st,ca)); | |
1625 | } | |
1626 | for (i=0; i<dst->npeers; i++) { | |
1627 | struct timeval diff; | |
1628 | timersub(tv_now,&dst->peers[i].last,&diff); | |
1629 | const struct comm_addr *ca=&dst->peers[i].addr; | |
1630 | slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld", | |
1631 | i, ca->comm->addr_to_string(ca->comm->st,ca), | |
1632 | (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec); | |
1633 | } | |
1634 | } | |
1635 | ||
1636 | static int transport_peer_compar(const void *av, const void *bv) { | |
1637 | const transport_peer *a=av; | |
1638 | const transport_peer *b=bv; | |
1639 | /* put most recent first in the array */ | |
1640 | if (timercmp(&a->last, &b->last, <)) return +1; | |
1641 | if (timercmp(&a->last, &b->last, >)) return -11; | |
1642 | return 0; | |
1643 | } | |
1644 | ||
1645 | static void transport_peers_expire(struct site *st, transport_peers *peers) { | |
1646 | /* peers must be sorted first */ | |
1647 | int previous_peers=peers->npeers; | |
1648 | struct timeval oldest; | |
1649 | oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry; | |
1650 | oldest.tv_usec = tv_now->tv_usec; | |
1651 | while (peers->npeers>1 && | |
1652 | timercmp(&peers->peers[peers->npeers-1].last, &oldest, <)) | |
1653 | peers->npeers--; | |
1654 | if (peers->npeers != previous_peers) | |
1655 | transport_peers_debug(st,peers,"expire", 0,0,0); | |
1656 | } | |
1657 | ||
1658 | static void transport_record_peer(struct site *st, transport_peers *peers, | |
1659 | const struct comm_addr *addr, const char *m) { | |
1660 | int slot, changed=0; | |
1661 | ||
1662 | for (slot=0; slot<peers->npeers; slot++) | |
1663 | if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr))) | |
1664 | goto found; | |
1665 | ||
1666 | changed=1; | |
1667 | if (peers->npeers==st->transport_peers_max) | |
1668 | slot=st->transport_peers_max; | |
1669 | else | |
1670 | slot=peers->npeers++; | |
1671 | ||
1672 | found: | |
1673 | peers->peers[slot].addr=*addr; | |
1674 | peers->peers[slot].last=*tv_now; | |
1675 | ||
1676 | if (peers->npeers>1) | |
1677 | qsort(peers->peers, peers->npeers, | |
1678 | sizeof(*peers->peers), transport_peer_compar); | |
1679 | ||
1680 | if (changed || peers->npeers!=1) | |
1681 | transport_peers_debug(st,peers,m, 1,addr,0); | |
1682 | transport_peers_expire(st, peers); | |
1683 | } | |
1684 | ||
1685 | static bool_t transport_compute_setupinit_peers(struct site *st, | |
1686 | const struct comm_addr *configured_addr /* 0 if none or not found */) { | |
1687 | ||
1688 | if (!configured_addr && !transport_peers_valid(&st->peers)) | |
1689 | return False; | |
1690 | ||
1691 | slog(st,LOG_SETUP_INIT, | |
1692 | (!configured_addr ? "using only %d old peer address(es)" | |
1693 | : "using configured address, and/or perhaps %d old peer address(es)"), | |
1694 | st->peers); | |
1695 | ||
1696 | /* Non-mobile peers havve st->peers.npeers==0 or ==1, since they | |
1697 | * have transport_peers_max==1. The effect is that this code | |
1698 | * always uses the configured address if supplied, or otherwise | |
1699 | * the existing data peer if one exists; this is as desired. */ | |
1700 | ||
1701 | transport_peers_copy(st,&st->setup_peers,&st->peers); | |
1702 | ||
1703 | if (configured_addr) | |
1704 | transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit"); | |
1705 | ||
1706 | assert(transport_peers_valid(&st->setup_peers)); | |
1707 | return True; | |
1708 | } | |
1709 | ||
1710 | static void transport_setup_msgok(struct site *st, const struct comm_addr *a) { | |
1711 | if (st->peer_mobile) | |
1712 | transport_record_peer(st,&st->setup_peers,a,"setupmsg"); | |
1713 | } | |
1714 | static void transport_data_msgok(struct site *st, const struct comm_addr *a) { | |
1715 | if (st->peer_mobile) | |
1716 | transport_record_peer(st,&st->peers,a,"datamsg"); | |
1717 | } | |
1718 | ||
1719 | static int transport_peers_valid(transport_peers *peers) { | |
1720 | return peers->npeers; | |
1721 | } | |
1722 | static void transport_peers_clear(struct site *st, transport_peers *peers) { | |
1723 | peers->npeers= 0; | |
1724 | transport_peers_debug(st,peers,"clear",0,0,0); | |
1725 | } | |
1726 | static void transport_peers_copy(struct site *st, transport_peers *dst, | |
1727 | const transport_peers *src) { | |
1728 | dst->npeers=src->npeers; | |
1729 | memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers); | |
1730 | transport_peers_debug(st,dst,"copy", | |
a620a048 | 1731 | src->npeers, &src->peers->addr, sizeof(*src->peers)); |
446353cd IJ |
1732 | } |
1733 | ||
1734 | void transport_xmit(struct site *st, transport_peers *peers, | |
1735 | struct buffer_if *buf, bool_t candebug) { | |
1736 | int slot; | |
1737 | transport_peers_expire(st, peers); | |
1738 | for (slot=0; slot<peers->npeers; slot++) { | |
1739 | transport_peer *peer=&peers->peers[slot]; | |
1740 | if (candebug) | |
1741 | dump_packet(st, buf, &peer->addr, False); | |
1742 | peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr); | |
1743 | } | |
1744 | } | |
1745 | ||
1746 | /***** END of transport peers declarations *****/ |