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 | ||
1737eeef IJ |
350 | struct parsedname { |
351 | int32_t len; | |
352 | uint8_t *name; | |
353 | int32_t extrainfo_len; | |
354 | uint8_t *extrainfo; | |
355 | }; | |
356 | ||
2fe58dfd SE |
357 | struct msg { |
358 | uint8_t *hashstart; | |
359 | uint32_t dest; | |
360 | uint32_t source; | |
1737eeef IJ |
361 | struct parsedname remote; |
362 | struct parsedname local; | |
2fe58dfd SE |
363 | uint8_t *nR; |
364 | uint8_t *nL; | |
1caa23ff | 365 | int32_t pklen; |
3e8addad | 366 | char *pk; |
1caa23ff IJ |
367 | int32_t hashlen; |
368 | int32_t siglen; | |
3e8addad | 369 | char *sig; |
2fe58dfd SE |
370 | }; |
371 | ||
ff05a229 SE |
372 | /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside |
373 | out using a transform of config data supplied by netlink */ | |
fe5e9cc4 | 374 | static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what) |
2fe58dfd SE |
375 | { |
376 | void *hst; | |
3b83c932 | 377 | uint8_t *hash; |
2fe58dfd SE |
378 | string_t dhpub, sig; |
379 | ||
380 | st->retries=st->setup_retries; | |
381 | BUF_ALLOC(&st->buffer,what); | |
382 | buffer_init(&st->buffer,0); | |
59635212 SE |
383 | buf_append_uint32(&st->buffer, |
384 | (type==LABEL_MSG1?0:st->setup_session_id)); | |
58650a70 | 385 | buf_append_uint32(&st->buffer,st->index); |
59635212 | 386 | buf_append_uint32(&st->buffer,type); |
2fe58dfd SE |
387 | buf_append_string(&st->buffer,st->localname); |
388 | buf_append_string(&st->buffer,st->remotename); | |
389 | memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN); | |
390 | if (type==LABEL_MSG1) return True; | |
391 | memcpy(buf_append(&st->buffer,NONCELEN),st->remoteN,NONCELEN); | |
392 | if (type==LABEL_MSG2) return True; | |
3b83c932 SE |
393 | |
394 | if (hacky_par_mid_failnow()) return False; | |
395 | ||
2fe58dfd SE |
396 | dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len); |
397 | buf_append_string(&st->buffer,dhpub); | |
398 | free(dhpub); | |
3b83c932 | 399 | hash=safe_malloc(st->hash->len, "generate_msg"); |
2fe58dfd SE |
400 | hst=st->hash->init(); |
401 | st->hash->update(hst,st->buffer.start,st->buffer.size); | |
402 | st->hash->final(hst,hash); | |
403 | sig=st->privkey->sign(st->privkey->st,hash,st->hash->len); | |
404 | buf_append_string(&st->buffer,sig); | |
405 | free(sig); | |
3b83c932 | 406 | free(hash); |
2fe58dfd SE |
407 | return True; |
408 | } | |
409 | ||
1737eeef IJ |
410 | static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm) |
411 | { | |
412 | CHECK_AVAIL(msg,2); | |
413 | nm->len=buf_unprepend_uint16(msg); | |
414 | CHECK_AVAIL(msg,nm->len); | |
415 | nm->name=buf_unprepend(msg,nm->len); | |
416 | uint8_t *nul=memchr(nm->name,0,nm->len); | |
417 | if (!nul) { | |
418 | nm->extrainfo_len=0; | |
419 | nm->extrainfo=0; | |
420 | } else { | |
421 | nm->extrainfo=nul+1; | |
422 | nm->extrainfo_len=msg->start-nm->extrainfo; | |
423 | nm->len=nul-nm->name; | |
424 | } | |
425 | return True; | |
426 | } | |
427 | ||
2fe58dfd SE |
428 | static bool_t unpick_msg(struct site *st, uint32_t type, |
429 | struct buffer_if *msg, struct msg *m) | |
430 | { | |
431 | m->hashstart=msg->start; | |
432 | CHECK_AVAIL(msg,4); | |
59635212 | 433 | m->dest=buf_unprepend_uint32(msg); |
2fe58dfd | 434 | CHECK_AVAIL(msg,4); |
59635212 | 435 | m->source=buf_unprepend_uint32(msg); |
2fe58dfd | 436 | CHECK_TYPE(msg,type); |
1737eeef IJ |
437 | if (!unpick_name(msg,&m->remote)) return False; |
438 | if (!unpick_name(msg,&m->local)) return False; | |
2fe58dfd SE |
439 | CHECK_AVAIL(msg,NONCELEN); |
440 | m->nR=buf_unprepend(msg,NONCELEN); | |
441 | if (type==LABEL_MSG1) { | |
442 | CHECK_EMPTY(msg); | |
443 | return True; | |
444 | } | |
445 | CHECK_AVAIL(msg,NONCELEN); | |
446 | m->nL=buf_unprepend(msg,NONCELEN); | |
447 | if (type==LABEL_MSG2) { | |
448 | CHECK_EMPTY(msg); | |
449 | return True; | |
450 | } | |
451 | CHECK_AVAIL(msg,2); | |
59635212 | 452 | m->pklen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
453 | CHECK_AVAIL(msg,m->pklen); |
454 | m->pk=buf_unprepend(msg,m->pklen); | |
455 | m->hashlen=msg->start-m->hashstart; | |
456 | CHECK_AVAIL(msg,2); | |
59635212 | 457 | m->siglen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
458 | CHECK_AVAIL(msg,m->siglen); |
459 | m->sig=buf_unprepend(msg,m->siglen); | |
460 | CHECK_EMPTY(msg); | |
461 | return True; | |
462 | } | |
463 | ||
1737eeef IJ |
464 | static bool_t name_matches(const struct parsedname *nm, const char *expected) |
465 | { | |
466 | int expected_len=strlen(expected); | |
467 | return | |
468 | nm->len == expected_len && | |
469 | !memcmp(nm->name, expected, expected_len); | |
470 | } | |
471 | ||
ff05a229 | 472 | static bool_t check_msg(struct site *st, uint32_t type, struct msg *m, |
fe5e9cc4 | 473 | cstring_t *error) |
ff05a229 SE |
474 | { |
475 | if (type==LABEL_MSG1) return True; | |
476 | ||
477 | /* Check that the site names and our nonce have been sent | |
478 | back correctly, and then store our peer's nonce. */ | |
1737eeef | 479 | if (!name_matches(&m->remote,st->remotename)) { |
ff05a229 SE |
480 | *error="wrong remote site name"; |
481 | return False; | |
482 | } | |
1737eeef | 483 | if (!name_matches(&m->local,st->localname)) { |
ff05a229 SE |
484 | *error="wrong local site name"; |
485 | return False; | |
486 | } | |
487 | if (memcmp(m->nL,st->localN,NONCELEN)!=0) { | |
488 | *error="wrong locally-generated nonce"; | |
489 | return False; | |
490 | } | |
491 | if (type==LABEL_MSG2) return True; | |
5ad34db2 | 492 | if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) { |
ff05a229 SE |
493 | *error="wrong remotely-generated nonce"; |
494 | return False; | |
495 | } | |
496 | if (type==LABEL_MSG3) return True; | |
497 | if (type==LABEL_MSG4) return True; | |
498 | *error="unknown message type"; | |
499 | return False; | |
500 | } | |
501 | ||
2fe58dfd SE |
502 | static bool_t generate_msg1(struct site *st) |
503 | { | |
504 | st->random->generate(st->random->st,NONCELEN,st->localN); | |
505 | return generate_msg(st,LABEL_MSG1,"site:MSG1"); | |
506 | } | |
507 | ||
508 | static bool_t process_msg1(struct site *st, struct buffer_if *msg1, | |
a15faeb2 | 509 | const struct comm_addr *src) |
2fe58dfd SE |
510 | { |
511 | struct msg m; | |
512 | ||
513 | /* We've already determined we're in an appropriate state to | |
514 | process an incoming MSG1, and that the MSG1 has correct values | |
515 | of A and B. */ | |
516 | ||
517 | if (!unpick_msg(st,LABEL_MSG1,msg1,&m)) return False; | |
518 | ||
446353cd | 519 | transport_record_peer(st,&st->setup_peers,src,"msg1"); |
2fe58dfd SE |
520 | st->setup_session_id=m.source; |
521 | memcpy(st->remoteN,m.nR,NONCELEN); | |
522 | return True; | |
523 | } | |
524 | ||
525 | static bool_t generate_msg2(struct site *st) | |
526 | { | |
527 | st->random->generate(st->random->st,NONCELEN,st->localN); | |
528 | return generate_msg(st,LABEL_MSG2,"site:MSG2"); | |
529 | } | |
530 | ||
531 | static bool_t process_msg2(struct site *st, struct buffer_if *msg2, | |
a15faeb2 | 532 | const struct comm_addr *src) |
2fe58dfd SE |
533 | { |
534 | struct msg m; | |
fe5e9cc4 | 535 | cstring_t err; |
2fe58dfd SE |
536 | |
537 | if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False; | |
ff05a229 SE |
538 | if (!check_msg(st,LABEL_MSG2,&m,&err)) { |
539 | slog(st,LOG_SEC,"msg2: %s",err); | |
2fe58dfd SE |
540 | return False; |
541 | } | |
542 | st->setup_session_id=m.source; | |
543 | memcpy(st->remoteN,m.nR,NONCELEN); | |
544 | return True; | |
545 | } | |
546 | ||
547 | static bool_t generate_msg3(struct site *st) | |
548 | { | |
549 | /* Now we have our nonce and their nonce. Think of a secret key, | |
550 | and create message number 3. */ | |
551 | st->random->generate(st->random->st,st->dh->len,st->dhsecret); | |
552 | return generate_msg(st,LABEL_MSG3,"site:MSG3"); | |
553 | } | |
554 | ||
555 | static bool_t process_msg3(struct site *st, struct buffer_if *msg3, | |
a15faeb2 | 556 | const struct comm_addr *src) |
2fe58dfd SE |
557 | { |
558 | struct msg m; | |
3b83c932 | 559 | uint8_t *hash; |
2fe58dfd | 560 | void *hst; |
fe5e9cc4 | 561 | cstring_t err; |
2fe58dfd SE |
562 | |
563 | if (!unpick_msg(st,LABEL_MSG3,msg3,&m)) return False; | |
ff05a229 SE |
564 | if (!check_msg(st,LABEL_MSG3,&m,&err)) { |
565 | slog(st,LOG_SEC,"msg3: %s",err); | |
2fe58dfd SE |
566 | return False; |
567 | } | |
ff05a229 | 568 | |
2fe58dfd | 569 | /* Check signature and store g^x mod m */ |
3b83c932 | 570 | hash=safe_malloc(st->hash->len, "process_msg3"); |
2fe58dfd SE |
571 | hst=st->hash->init(); |
572 | st->hash->update(hst,m.hashstart,m.hashlen); | |
573 | st->hash->final(hst,hash); | |
574 | /* Terminate signature with a '0' - cheating, but should be ok */ | |
575 | m.sig[m.siglen]=0; | |
576 | if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) { | |
59635212 | 577 | slog(st,LOG_SEC,"msg3 signature failed check!"); |
3b83c932 | 578 | free(hash); |
2fe58dfd SE |
579 | return False; |
580 | } | |
3b83c932 | 581 | free(hash); |
2fe58dfd SE |
582 | |
583 | /* Terminate their DH public key with a '0' */ | |
584 | m.pk[m.pklen]=0; | |
585 | /* Invent our DH secret key */ | |
586 | st->random->generate(st->random->st,st->dh->len,st->dhsecret); | |
587 | ||
588 | /* Generate the shared key */ | |
589 | st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk, | |
7c9ca4bd | 590 | st->sharedsecret,st->sharedsecretlen); |
2fe58dfd SE |
591 | |
592 | /* Set up the transform */ | |
593 | st->new_transform->setkey(st->new_transform->st,st->sharedsecret, | |
0118121a | 594 | st->sharedsecretlen,st->setup_priority); |
2fe58dfd SE |
595 | |
596 | return True; | |
597 | } | |
598 | ||
599 | static bool_t generate_msg4(struct site *st) | |
600 | { | |
601 | /* We have both nonces, their public key and our private key. Generate | |
602 | our public key, sign it and send it to them. */ | |
603 | return generate_msg(st,LABEL_MSG4,"site:MSG4"); | |
604 | } | |
605 | ||
606 | static bool_t process_msg4(struct site *st, struct buffer_if *msg4, | |
a15faeb2 | 607 | const struct comm_addr *src) |
2fe58dfd SE |
608 | { |
609 | struct msg m; | |
3b83c932 | 610 | uint8_t *hash; |
2fe58dfd | 611 | void *hst; |
fe5e9cc4 | 612 | cstring_t err; |
2fe58dfd SE |
613 | |
614 | if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False; | |
ff05a229 SE |
615 | if (!check_msg(st,LABEL_MSG4,&m,&err)) { |
616 | slog(st,LOG_SEC,"msg4: %s",err); | |
2fe58dfd SE |
617 | return False; |
618 | } | |
619 | ||
620 | /* Check signature and store g^x mod m */ | |
3b83c932 | 621 | hash=safe_malloc(st->hash->len, "process_msg4"); |
2fe58dfd SE |
622 | hst=st->hash->init(); |
623 | st->hash->update(hst,m.hashstart,m.hashlen); | |
624 | st->hash->final(hst,hash); | |
625 | /* Terminate signature with a '0' - cheating, but should be ok */ | |
626 | m.sig[m.siglen]=0; | |
627 | if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) { | |
59635212 | 628 | slog(st,LOG_SEC,"msg4 signature failed check!"); |
3b83c932 | 629 | free(hash); |
2fe58dfd SE |
630 | return False; |
631 | } | |
3b83c932 | 632 | free(hash); |
2fe58dfd SE |
633 | |
634 | /* Terminate their DH public key with a '0' */ | |
635 | m.pk[m.pklen]=0; | |
636 | /* Generate the shared key */ | |
637 | st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk, | |
7c9ca4bd | 638 | st->sharedsecret,st->sharedsecretlen); |
2fe58dfd SE |
639 | /* Set up the transform */ |
640 | st->new_transform->setkey(st->new_transform->st,st->sharedsecret, | |
0118121a | 641 | st->sharedsecretlen,st->setup_priority); |
2fe58dfd SE |
642 | |
643 | return True; | |
644 | } | |
645 | ||
2fe58dfd SE |
646 | struct msg0 { |
647 | uint32_t dest; | |
648 | uint32_t source; | |
649 | uint32_t type; | |
650 | }; | |
651 | ||
652 | static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0, | |
653 | struct msg0 *m) | |
654 | { | |
655 | CHECK_AVAIL(msg0,4); | |
59635212 | 656 | m->dest=buf_unprepend_uint32(msg0); |
2fe58dfd | 657 | CHECK_AVAIL(msg0,4); |
59635212 | 658 | m->source=buf_unprepend_uint32(msg0); |
2fe58dfd | 659 | CHECK_AVAIL(msg0,4); |
59635212 | 660 | m->type=buf_unprepend_uint32(msg0); |
2fe58dfd SE |
661 | return True; |
662 | /* Leaves transformed part of buffer untouched */ | |
663 | } | |
664 | ||
ff05a229 SE |
665 | static bool_t generate_msg5(struct site *st) |
666 | { | |
fe5e9cc4 | 667 | cstring_t transform_err; |
ff05a229 SE |
668 | |
669 | BUF_ALLOC(&st->buffer,"site:MSG5"); | |
670 | /* We are going to add four words to the message */ | |
671 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*4)); | |
672 | /* Give the netlink code an opportunity to put its own stuff in the | |
673 | message (configuration information, etc.) */ | |
ff05a229 SE |
674 | buf_prepend_uint32(&st->buffer,LABEL_MSG5); |
675 | st->new_transform->forwards(st->new_transform->st,&st->buffer, | |
676 | &transform_err); | |
677 | buf_prepend_uint32(&st->buffer,LABEL_MSG5); | |
58650a70 | 678 | buf_prepend_uint32(&st->buffer,st->index); |
ff05a229 SE |
679 | buf_prepend_uint32(&st->buffer,st->setup_session_id); |
680 | ||
681 | st->retries=st->setup_retries; | |
682 | return True; | |
683 | } | |
684 | ||
2fe58dfd | 685 | static bool_t process_msg5(struct site *st, struct buffer_if *msg5, |
c90cc2a7 IJ |
686 | const struct comm_addr *src, |
687 | struct transform_inst_if *transform) | |
2fe58dfd SE |
688 | { |
689 | struct msg0 m; | |
fe5e9cc4 | 690 | cstring_t transform_err; |
2fe58dfd SE |
691 | |
692 | if (!unpick_msg0(st,msg5,&m)) return False; | |
693 | ||
c90cc2a7 | 694 | if (transform->reverse(transform->st,msg5,&transform_err)) { |
2fe58dfd | 695 | /* There's a problem */ |
59635212 | 696 | slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err); |
2fe58dfd SE |
697 | return False; |
698 | } | |
699 | /* Buffer should now contain untransformed PING packet data */ | |
700 | CHECK_AVAIL(msg5,4); | |
59635212 | 701 | if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) { |
ff05a229 | 702 | slog(st,LOG_SEC,"MSG5/PING packet contained wrong label"); |
2fe58dfd SE |
703 | return False; |
704 | } | |
ff7cdc9e IJ |
705 | /* Older versions of secnet used to write some config data here |
706 | * which we ignore. So we don't CHECK_EMPTY */ | |
2fe58dfd SE |
707 | return True; |
708 | } | |
709 | ||
c90cc2a7 IJ |
710 | static void create_msg6(struct site *st, struct transform_inst_if *transform, |
711 | uint32_t session_id) | |
2fe58dfd | 712 | { |
fe5e9cc4 | 713 | cstring_t transform_err; |
2fe58dfd SE |
714 | |
715 | BUF_ALLOC(&st->buffer,"site:MSG6"); | |
ff05a229 SE |
716 | /* We are going to add four words to the message */ |
717 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*4)); | |
794f2398 SE |
718 | /* Give the netlink code an opportunity to put its own stuff in the |
719 | message (configuration information, etc.) */ | |
ff05a229 | 720 | buf_prepend_uint32(&st->buffer,LABEL_MSG6); |
c90cc2a7 | 721 | transform->forwards(transform->st,&st->buffer,&transform_err); |
59635212 | 722 | buf_prepend_uint32(&st->buffer,LABEL_MSG6); |
58650a70 | 723 | buf_prepend_uint32(&st->buffer,st->index); |
c90cc2a7 IJ |
724 | buf_prepend_uint32(&st->buffer,session_id); |
725 | } | |
2fe58dfd | 726 | |
c90cc2a7 IJ |
727 | static bool_t generate_msg6(struct site *st) |
728 | { | |
729 | create_msg6(st,st->new_transform,st->setup_session_id); | |
ff05a229 | 730 | st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */ |
2fe58dfd SE |
731 | return True; |
732 | } | |
733 | ||
734 | static bool_t process_msg6(struct site *st, struct buffer_if *msg6, | |
a15faeb2 | 735 | const struct comm_addr *src) |
2fe58dfd SE |
736 | { |
737 | struct msg0 m; | |
fe5e9cc4 | 738 | cstring_t transform_err; |
2fe58dfd SE |
739 | |
740 | if (!unpick_msg0(st,msg6,&m)) return False; | |
741 | ||
742 | if (st->new_transform->reverse(st->new_transform->st, | |
743 | msg6,&transform_err)) { | |
744 | /* There's a problem */ | |
59635212 | 745 | slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err); |
2fe58dfd SE |
746 | return False; |
747 | } | |
748 | /* Buffer should now contain untransformed PING packet data */ | |
749 | CHECK_AVAIL(msg6,4); | |
59635212 SE |
750 | if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) { |
751 | slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data"); | |
2fe58dfd SE |
752 | return False; |
753 | } | |
ff7cdc9e IJ |
754 | /* Older versions of secnet used to write some config data here |
755 | * which we ignore. So we don't CHECK_EMPTY */ | |
2fe58dfd SE |
756 | return True; |
757 | } | |
758 | ||
48b97423 IJ |
759 | static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0, |
760 | const struct comm_addr *src) | |
2fe58dfd | 761 | { |
02b0959b | 762 | cstring_t transform_err, auxkey_err, newkey_err="n/a"; |
065e1922 IJ |
763 | struct msg0 m; |
764 | uint32_t problem; | |
2fe58dfd | 765 | |
2fe58dfd SE |
766 | if (!unpick_msg0(st,msg0,&m)) return False; |
767 | ||
05f39b4d IJ |
768 | /* Keep a copy so we can try decrypting it with multiple keys */ |
769 | buffer_copy(&st->scratch, msg0); | |
770 | ||
19e9a588 | 771 | problem = st->current.transform->reverse(st->current.transform->st, |
065e1922 | 772 | msg0,&transform_err); |
02b0959b | 773 | if (!problem) { |
bd98cd6b IJ |
774 | if (!st->auxiliary_is_new) |
775 | delete_one_key(st,&st->auxiliary_key, | |
776 | "peer has used new key","auxiliary key",LOG_SEC); | |
02b0959b IJ |
777 | return True; |
778 | } | |
48b97423 IJ |
779 | if (problem==2) |
780 | goto skew; | |
07e4774c | 781 | |
02b0959b IJ |
782 | buffer_copy(msg0, &st->scratch); |
783 | problem = st->auxiliary_key.transform->reverse | |
784 | (st->auxiliary_key.transform->st,msg0,&auxkey_err); | |
785 | if (problem==0) { | |
786 | slog(st,LOG_DROP,"processing packet which uses auxiliary key"); | |
bd98cd6b IJ |
787 | if (st->auxiliary_is_new) { |
788 | /* We previously timed out in state SENTMSG5 but it turns | |
789 | * out that our peer did in fact get our MSG5 and is | |
790 | * using the new key. So we should switch to it too. */ | |
791 | /* This is a bit like activate_new_key. */ | |
792 | struct data_key t; | |
793 | t=st->current; | |
794 | st->current=st->auxiliary_key; | |
795 | st->auxiliary_key=t; | |
796 | ||
797 | delete_one_key(st,&st->auxiliary_key,"peer has used new key", | |
798 | "previous key",LOG_SEC); | |
799 | st->auxiliary_is_new=0; | |
800 | st->renegotiate_key_time=st->auxiliary_renegotiate_key_time; | |
801 | } | |
02b0959b IJ |
802 | return True; |
803 | } | |
48b97423 IJ |
804 | if (problem==2) |
805 | goto skew; | |
02b0959b | 806 | |
05f39b4d IJ |
807 | if (st->state==SITE_SENTMSG5) { |
808 | buffer_copy(msg0, &st->scratch); | |
48b97423 IJ |
809 | problem = st->new_transform->reverse(st->new_transform->st, |
810 | msg0,&newkey_err); | |
811 | if (!problem) { | |
05f39b4d IJ |
812 | /* It looks like we didn't get the peer's MSG6 */ |
813 | /* This is like a cut-down enter_new_state(SITE_RUN) */ | |
814 | slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)"); | |
815 | BUF_FREE(&st->buffer); | |
816 | st->timeout=0; | |
817 | activate_new_key(st); | |
818 | return True; /* do process the data in this packet */ | |
819 | } | |
48b97423 IJ |
820 | if (problem==2) |
821 | goto skew; | |
05f39b4d IJ |
822 | } |
823 | ||
02b0959b IJ |
824 | slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)", |
825 | transform_err,auxkey_err,newkey_err); | |
065e1922 | 826 | initiate_key_setup(st,"incoming message would not decrypt"); |
48b97423 IJ |
827 | send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt"); |
828 | return False; | |
829 | ||
830 | skew: | |
831 | slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err); | |
065e1922 IJ |
832 | return False; |
833 | } | |
834 | ||
835 | static bool_t process_msg0(struct site *st, struct buffer_if *msg0, | |
836 | const struct comm_addr *src) | |
837 | { | |
838 | uint32_t type; | |
839 | ||
48b97423 | 840 | if (!decrypt_msg0(st,msg0,src)) |
065e1922 IJ |
841 | return False; |
842 | ||
2fe58dfd | 843 | CHECK_AVAIL(msg0,4); |
59635212 | 844 | type=buf_unprepend_uint32(msg0); |
2fe58dfd | 845 | switch(type) { |
794f2398 SE |
846 | case LABEL_MSG7: |
847 | /* We must forget about the current session. */ | |
1d388569 | 848 | delete_keys(st,"request from peer",LOG_SEC); |
794f2398 | 849 | return True; |
2fe58dfd SE |
850 | case LABEL_MSG9: |
851 | /* Deliver to netlink layer */ | |
469fd1d9 | 852 | st->netlink->deliver(st->netlink->st,msg0); |
446353cd | 853 | transport_data_msgok(st,src); |
837cf01e IJ |
854 | /* See whether we should start negotiating a new key */ |
855 | if (st->now > st->renegotiate_key_time) | |
856 | initiate_key_setup(st,"incoming packet in renegotiation window"); | |
2fe58dfd | 857 | return True; |
2fe58dfd | 858 | default: |
ff05a229 SE |
859 | slog(st,LOG_SEC,"incoming encrypted message of type %08x " |
860 | "(unknown)",type); | |
2fe58dfd SE |
861 | break; |
862 | } | |
863 | return False; | |
864 | } | |
865 | ||
866 | static void dump_packet(struct site *st, struct buffer_if *buf, | |
a15faeb2 | 867 | const struct comm_addr *addr, bool_t incoming) |
2fe58dfd | 868 | { |
59635212 SE |
869 | uint32_t dest=ntohl(*(uint32_t *)buf->start); |
870 | uint32_t source=ntohl(*(uint32_t *)(buf->start+4)); | |
871 | uint32_t msgtype=ntohl(*(uint32_t *)(buf->start+8)); | |
2fe58dfd SE |
872 | |
873 | if (st->log_events & LOG_DUMP) | |
040ee979 SE |
874 | slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x:", |
875 | st->tunname,incoming?"incoming":"outgoing", | |
876 | dest,source,msgtype); | |
2fe58dfd SE |
877 | } |
878 | ||
879 | static uint32_t site_status(void *st) | |
880 | { | |
881 | return 0; | |
882 | } | |
883 | ||
884 | static bool_t send_msg(struct site *st) | |
885 | { | |
886 | if (st->retries>0) { | |
446353cd | 887 | transport_xmit(st, &st->setup_peers, &st->buffer, True); |
e7f8ec2a | 888 | st->timeout=st->now+st->setup_retry_interval; |
2fe58dfd SE |
889 | st->retries--; |
890 | return True; | |
bd98cd6b IJ |
891 | } else if (st->state==SITE_SENTMSG5) { |
892 | slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key"); | |
893 | /* We stash the key we have produced, in case it turns out that | |
894 | * our peer did see our MSG5 after all and starts using it. */ | |
895 | /* This is a bit like some of activate_new_key */ | |
896 | struct transform_inst_if *t; | |
897 | t=st->auxiliary_key.transform; | |
898 | st->auxiliary_key.transform=st->new_transform; | |
899 | st->new_transform=t; | |
900 | ||
901 | t->delkey(t->st); | |
902 | st->auxiliary_is_new=1; | |
903 | st->auxiliary_key.key_timeout=st->now+st->key_lifetime; | |
904 | st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time; | |
905 | st->auxiliary_key.remote_session_id=st->setup_session_id; | |
906 | ||
907 | enter_state_wait(st); | |
908 | return False; | |
2fe58dfd | 909 | } else { |
3454dce4 SE |
910 | slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet " |
911 | "(in state %s)",state_name(st->state)); | |
2fe58dfd SE |
912 | enter_state_wait(st); |
913 | return False; | |
914 | } | |
915 | } | |
916 | ||
917 | static void site_resolve_callback(void *sst, struct in_addr *address) | |
918 | { | |
919 | struct site *st=sst; | |
446353cd | 920 | struct comm_addr ca_buf, *ca_use; |
2fe58dfd SE |
921 | |
922 | if (st->state!=SITE_RESOLVE) { | |
923 | slog(st,LOG_UNEXPECTED,"site_resolve_callback called unexpectedly"); | |
924 | return; | |
925 | } | |
926 | if (address) { | |
446353cd | 927 | FILLZERO(ca_buf); |
59533c16 | 928 | ca_buf.comm=st->comms[0]; |
446353cd IJ |
929 | ca_buf.sin.sin_family=AF_INET; |
930 | ca_buf.sin.sin_port=htons(st->remoteport); | |
931 | ca_buf.sin.sin_addr=*address; | |
932 | ca_use=&ca_buf; | |
2fe58dfd | 933 | } else { |
2fe58dfd | 934 | slog(st,LOG_ERROR,"resolution of %s failed",st->address); |
446353cd IJ |
935 | ca_use=0; |
936 | } | |
937 | if (transport_compute_setupinit_peers(st,ca_use)) { | |
938 | enter_new_state(st,SITE_SENTMSG1); | |
939 | } else { | |
940 | /* Can't figure out who to try to to talk to */ | |
941 | slog(st,LOG_SETUP_INIT,"key exchange failed: cannot find peer address"); | |
2fe58dfd SE |
942 | enter_state_run(st); |
943 | } | |
944 | } | |
945 | ||
fe5e9cc4 | 946 | static bool_t initiate_key_setup(struct site *st, cstring_t reason) |
9d3a4132 SE |
947 | { |
948 | if (st->state!=SITE_RUN) return False; | |
794f2398 | 949 | slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason); |
9d3a4132 | 950 | if (st->address) { |
794f2398 | 951 | slog(st,LOG_SETUP_INIT,"resolving peer address"); |
9d3a4132 | 952 | return enter_state_resolve(st); |
446353cd | 953 | } else if (transport_compute_setupinit_peers(st,0)) { |
ff05a229 | 954 | return enter_new_state(st,SITE_SENTMSG1); |
9d3a4132 | 955 | } |
ff05a229 | 956 | slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer"); |
9d3a4132 SE |
957 | return False; |
958 | } | |
959 | ||
2fe58dfd SE |
960 | static void activate_new_key(struct site *st) |
961 | { | |
962 | struct transform_inst_if *t; | |
963 | ||
02b0959b IJ |
964 | /* We have three transform instances, which we swap between old, |
965 | active and setup */ | |
966 | t=st->auxiliary_key.transform; | |
967 | st->auxiliary_key.transform=st->current.transform; | |
19e9a588 | 968 | st->current.transform=st->new_transform; |
2fe58dfd SE |
969 | st->new_transform=t; |
970 | ||
971 | t->delkey(t->st); | |
2fe58dfd | 972 | st->timeout=0; |
bd98cd6b | 973 | st->auxiliary_is_new=0; |
02b0959b | 974 | st->auxiliary_key.key_timeout=st->current.key_timeout; |
19e9a588 | 975 | st->current.key_timeout=st->now+st->key_lifetime; |
ff05a229 | 976 | st->renegotiate_key_time=st->now+st->key_renegotiate_time; |
446353cd | 977 | transport_peers_copy(st,&st->peers,&st->setup_peers); |
19e9a588 | 978 | st->current.remote_session_id=st->setup_session_id; |
2fe58dfd SE |
979 | |
980 | slog(st,LOG_ACTIVATE_KEY,"new key activated"); | |
9d3a4132 | 981 | enter_state_run(st); |
2fe58dfd SE |
982 | } |
983 | ||
1d388569 IJ |
984 | static void delete_one_key(struct site *st, struct data_key *key, |
985 | cstring_t reason, cstring_t which, uint32_t loglevel) | |
986 | { | |
987 | if (!key->transform->valid(key->transform->st)) return; | |
988 | if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason); | |
989 | key->transform->delkey(key->transform->st); | |
990 | key->key_timeout=0; | |
991 | } | |
992 | ||
993 | static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel) | |
794f2398 | 994 | { |
3d8d8f4e | 995 | if (current_valid(st)) { |
794f2398 SE |
996 | slog(st,loglevel,"session closed (%s)",reason); |
997 | ||
1d388569 | 998 | delete_one_key(st,&st->current,0,0,0); |
794f2398 SE |
999 | set_link_quality(st); |
1000 | } | |
02b0959b | 1001 | delete_one_key(st,&st->auxiliary_key,0,0,0); |
794f2398 SE |
1002 | } |
1003 | ||
2fe58dfd SE |
1004 | static void state_assert(struct site *st, bool_t ok) |
1005 | { | |
4f5e39ec | 1006 | if (!ok) fatal("site:state_assert"); |
2fe58dfd SE |
1007 | } |
1008 | ||
1009 | static void enter_state_stop(struct site *st) | |
1010 | { | |
1011 | st->state=SITE_STOP; | |
1012 | st->timeout=0; | |
1d388569 | 1013 | delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY); |
2fe58dfd SE |
1014 | st->new_transform->delkey(st->new_transform->st); |
1015 | } | |
1016 | ||
9d3a4132 SE |
1017 | static void set_link_quality(struct site *st) |
1018 | { | |
1019 | uint32_t quality; | |
3d8d8f4e | 1020 | if (current_valid(st)) |
9d3a4132 SE |
1021 | quality=LINK_QUALITY_UP; |
1022 | else if (st->state==SITE_WAIT || st->state==SITE_STOP) | |
1023 | quality=LINK_QUALITY_DOWN; | |
1024 | else if (st->address) | |
1025 | quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS; | |
446353cd | 1026 | else if (transport_peers_valid(&st->peers)) |
9d3a4132 SE |
1027 | quality=LINK_QUALITY_DOWN_STALE_ADDRESS; |
1028 | else | |
1029 | quality=LINK_QUALITY_DOWN; | |
1030 | ||
469fd1d9 | 1031 | st->netlink->set_quality(st->netlink->st,quality); |
9d3a4132 SE |
1032 | } |
1033 | ||
2fe58dfd SE |
1034 | static void enter_state_run(struct site *st) |
1035 | { | |
1036 | slog(st,LOG_STATE,"entering state RUN"); | |
1037 | st->state=SITE_RUN; | |
1038 | st->timeout=0; | |
9d3a4132 | 1039 | |
ff05a229 | 1040 | st->setup_session_id=0; |
446353cd | 1041 | transport_peers_clear(st,&st->setup_peers); |
ff05a229 SE |
1042 | memset(st->localN,0,NONCELEN); |
1043 | memset(st->remoteN,0,NONCELEN); | |
1044 | st->new_transform->delkey(st->new_transform->st); | |
1045 | memset(st->dhsecret,0,st->dh->len); | |
7c9ca4bd | 1046 | memset(st->sharedsecret,0,st->sharedsecretlen); |
9d3a4132 | 1047 | set_link_quality(st); |
2fe58dfd SE |
1048 | } |
1049 | ||
1050 | static bool_t enter_state_resolve(struct site *st) | |
1051 | { | |
1052 | state_assert(st,st->state==SITE_RUN); | |
1053 | slog(st,LOG_STATE,"entering state RESOLVE"); | |
1054 | st->state=SITE_RESOLVE; | |
1055 | st->resolver->request(st->resolver->st,st->address, | |
1056 | site_resolve_callback,st); | |
1057 | return True; | |
1058 | } | |
1059 | ||
ff05a229 | 1060 | static bool_t enter_new_state(struct site *st, uint32_t next) |
2fe58dfd | 1061 | { |
ff05a229 | 1062 | bool_t (*gen)(struct site *st); |
3b83c932 SE |
1063 | int r; |
1064 | ||
ff05a229 SE |
1065 | slog(st,LOG_STATE,"entering state %s",state_name(next)); |
1066 | switch(next) { | |
1067 | case SITE_SENTMSG1: | |
1068 | state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE); | |
1069 | gen=generate_msg1; | |
1070 | break; | |
1071 | case SITE_SENTMSG2: | |
1072 | state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE || | |
1073 | st->state==SITE_SENTMSG1 || st->state==SITE_WAIT); | |
1074 | gen=generate_msg2; | |
1075 | break; | |
1076 | case SITE_SENTMSG3: | |
1077 | state_assert(st,st->state==SITE_SENTMSG1); | |
1078 | BUF_FREE(&st->buffer); | |
1079 | gen=generate_msg3; | |
1080 | break; | |
1081 | case SITE_SENTMSG4: | |
1082 | state_assert(st,st->state==SITE_SENTMSG2); | |
1083 | BUF_FREE(&st->buffer); | |
1084 | gen=generate_msg4; | |
1085 | break; | |
1086 | case SITE_SENTMSG5: | |
1087 | state_assert(st,st->state==SITE_SENTMSG3); | |
1088 | BUF_FREE(&st->buffer); | |
1089 | gen=generate_msg5; | |
1090 | break; | |
1091 | case SITE_RUN: | |
1092 | state_assert(st,st->state==SITE_SENTMSG4); | |
1093 | BUF_FREE(&st->buffer); | |
1094 | gen=generate_msg6; | |
1095 | break; | |
1096 | default: | |
1097 | gen=NULL; | |
4f5e39ec | 1098 | fatal("enter_new_state(%s): invalid new state",state_name(next)); |
ff05a229 | 1099 | break; |
2fe58dfd | 1100 | } |
2fe58dfd | 1101 | |
3b83c932 SE |
1102 | if (hacky_par_start_failnow()) return False; |
1103 | ||
1104 | r= gen(st) && send_msg(st); | |
1105 | ||
1106 | hacky_par_end(&r, | |
e7f8ec2a | 1107 | st->setup_retries, st->setup_retry_interval, |
3b83c932 SE |
1108 | send_msg, st); |
1109 | ||
1110 | if (r) { | |
ff05a229 SE |
1111 | st->state=next; |
1112 | if (next==SITE_RUN) { | |
1113 | BUF_FREE(&st->buffer); /* Never reused */ | |
1114 | st->timeout=0; /* Never retransmit */ | |
1115 | activate_new_key(st); | |
1116 | } | |
2fe58dfd SE |
1117 | return True; |
1118 | } | |
ff05a229 SE |
1119 | slog(st,LOG_ERROR,"error entering state %s",state_name(next)); |
1120 | st->buffer.free=False; /* Unconditionally use the buffer; it may be | |
1121 | in either state, and enter_state_wait() will | |
1122 | do a BUF_FREE() */ | |
2fe58dfd SE |
1123 | enter_state_wait(st); |
1124 | return False; | |
1125 | } | |
1126 | ||
ff05a229 | 1127 | /* msg7 tells our peer that we're about to forget our key */ |
fe5e9cc4 | 1128 | static bool_t send_msg7(struct site *st, cstring_t reason) |
794f2398 | 1129 | { |
fe5e9cc4 | 1130 | cstring_t transform_err; |
794f2398 | 1131 | |
3d8d8f4e | 1132 | if (current_valid(st) && st->buffer.free |
446353cd | 1133 | && transport_peers_valid(&st->peers)) { |
794f2398 SE |
1134 | BUF_ALLOC(&st->buffer,"site:MSG7"); |
1135 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*3)); | |
1136 | buf_append_uint32(&st->buffer,LABEL_MSG7); | |
1137 | buf_append_string(&st->buffer,reason); | |
19e9a588 | 1138 | st->current.transform->forwards(st->current.transform->st, |
794f2398 SE |
1139 | &st->buffer, &transform_err); |
1140 | buf_prepend_uint32(&st->buffer,LABEL_MSG0); | |
58650a70 | 1141 | buf_prepend_uint32(&st->buffer,st->index); |
19e9a588 | 1142 | buf_prepend_uint32(&st->buffer,st->current.remote_session_id); |
446353cd | 1143 | transport_xmit(st,&st->peers,&st->buffer,True); |
794f2398 SE |
1144 | BUF_FREE(&st->buffer); |
1145 | return True; | |
1146 | } | |
1147 | return False; | |
1148 | } | |
1149 | ||
2fe58dfd SE |
1150 | /* We go into this state if our peer becomes uncommunicative. Similar to |
1151 | the "stop" state, we forget all session keys for a while, before | |
1152 | re-entering the "run" state. */ | |
1153 | static void enter_state_wait(struct site *st) | |
1154 | { | |
1155 | slog(st,LOG_STATE,"entering state WAIT"); | |
1156 | st->timeout=st->now+st->wait_timeout; | |
1157 | st->state=SITE_WAIT; | |
9d3a4132 | 1158 | set_link_quality(st); |
2fe58dfd SE |
1159 | BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */ |
1160 | /* XXX Erase keys etc. */ | |
1161 | } | |
1162 | ||
16f73fa6 | 1163 | static inline void site_settimeout(uint64_t timeout, int *timeout_io) |
fe5e9cc4 SE |
1164 | { |
1165 | if (timeout) { | |
0009e60a IJ |
1166 | int64_t offset=timeout-*now; |
1167 | if (offset<0) offset=0; | |
fe5e9cc4 SE |
1168 | if (offset>INT_MAX) offset=INT_MAX; |
1169 | if (*timeout_io<0 || offset<*timeout_io) | |
1170 | *timeout_io=offset; | |
1171 | } | |
1172 | } | |
1173 | ||
2fe58dfd | 1174 | static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io, |
90a39563 | 1175 | int *timeout_io) |
2fe58dfd SE |
1176 | { |
1177 | struct site *st=sst; | |
1178 | ||
1179 | *nfds_io=0; /* We don't use any file descriptors */ | |
1180 | st->now=*now; | |
1181 | ||
1182 | /* Work out when our next timeout is. The earlier of 'timeout' or | |
19e9a588 | 1183 | 'current.key_timeout'. A stored value of '0' indicates no timeout |
2fe58dfd | 1184 | active. */ |
16f73fa6 | 1185 | site_settimeout(st->timeout, timeout_io); |
19e9a588 | 1186 | site_settimeout(st->current.key_timeout, timeout_io); |
02b0959b | 1187 | site_settimeout(st->auxiliary_key.key_timeout, timeout_io); |
2fe58dfd SE |
1188 | |
1189 | return 0; /* success */ | |
1190 | } | |
1191 | ||
1d388569 IJ |
1192 | static void check_expiry(struct site *st, struct data_key *key, |
1193 | const char *which) | |
1194 | { | |
1195 | if (key->key_timeout && *now>key->key_timeout) { | |
1196 | delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY); | |
1197 | } | |
1198 | } | |
1199 | ||
2fe58dfd | 1200 | /* NB site_afterpoll will be called before site_beforepoll is ever called */ |
90a39563 | 1201 | static void site_afterpoll(void *sst, struct pollfd *fds, int nfds) |
2fe58dfd SE |
1202 | { |
1203 | struct site *st=sst; | |
1204 | ||
1205 | st->now=*now; | |
1206 | if (st->timeout && *now>st->timeout) { | |
2fe58dfd | 1207 | st->timeout=0; |
3b83c932 SE |
1208 | if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) { |
1209 | if (!hacky_par_start_failnow()) | |
1210 | send_msg(st); | |
1211 | } else if (st->state==SITE_WAIT) { | |
2fe58dfd SE |
1212 | enter_state_run(st); |
1213 | } else { | |
1214 | slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d", | |
1215 | st->state); | |
1216 | } | |
1217 | } | |
1d388569 | 1218 | check_expiry(st,&st->current,"current key"); |
02b0959b | 1219 | check_expiry(st,&st->auxiliary_key,"auxiliary key"); |
2fe58dfd SE |
1220 | } |
1221 | ||
1222 | /* This function is called by the netlink device to deliver packets | |
1223 | intended for the remote network. The packet is in "raw" wire | |
1224 | format, but is guaranteed to be word-aligned. */ | |
469fd1d9 | 1225 | static void site_outgoing(void *sst, struct buffer_if *buf) |
2fe58dfd SE |
1226 | { |
1227 | struct site *st=sst; | |
fe5e9cc4 | 1228 | cstring_t transform_err; |
2fe58dfd SE |
1229 | |
1230 | if (st->state==SITE_STOP) { | |
1231 | BUF_FREE(buf); | |
1232 | return; | |
1233 | } | |
1234 | ||
1235 | /* In all other states we consider delivering the packet if we have | |
1236 | a valid key and a valid address to send it to. */ | |
3d8d8f4e | 1237 | if (current_valid(st) && transport_peers_valid(&st->peers)) { |
2fe58dfd | 1238 | /* Transform it and send it */ |
70dc107b SE |
1239 | if (buf->size>0) { |
1240 | buf_prepend_uint32(buf,LABEL_MSG9); | |
19e9a588 | 1241 | st->current.transform->forwards(st->current.transform->st, |
70dc107b SE |
1242 | buf, &transform_err); |
1243 | buf_prepend_uint32(buf,LABEL_MSG0); | |
58650a70 | 1244 | buf_prepend_uint32(buf,st->index); |
19e9a588 | 1245 | buf_prepend_uint32(buf,st->current.remote_session_id); |
446353cd | 1246 | transport_xmit(st,&st->peers,buf,False); |
70dc107b | 1247 | } |
2fe58dfd SE |
1248 | BUF_FREE(buf); |
1249 | return; | |
1250 | } | |
1251 | ||
70dc107b | 1252 | slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size); |
2fe58dfd | 1253 | BUF_FREE(buf); |
794f2398 | 1254 | initiate_key_setup(st,"outgoing packet"); |
2fe58dfd SE |
1255 | } |
1256 | ||
1257 | /* This function is called by the communication device to deliver | |
1258 | packets from our peers. */ | |
1259 | static bool_t site_incoming(void *sst, struct buffer_if *buf, | |
a15faeb2 | 1260 | const struct comm_addr *source) |
2fe58dfd SE |
1261 | { |
1262 | struct site *st=sst; | |
20138876 IJ |
1263 | |
1264 | if (buf->size < 12) return False; | |
1265 | ||
59635212 | 1266 | uint32_t dest=ntohl(*(uint32_t *)buf->start); |
2fe58dfd SE |
1267 | |
1268 | if (dest==0) { | |
2fe58dfd SE |
1269 | /* It could be for any site - it should have LABEL_MSG1 and |
1270 | might have our name and our peer's name in it */ | |
ff05a229 | 1271 | if (buf->size<(st->setupsiglen+8+NONCELEN)) return False; |
2fe58dfd | 1272 | if (memcmp(buf->start+8,st->setupsig,st->setupsiglen)==0) { |
2fe58dfd | 1273 | /* It's addressed to us. Decide what to do about it. */ |
ff05a229 | 1274 | dump_packet(st,buf,source,True); |
2fe58dfd SE |
1275 | if (st->state==SITE_RUN || st->state==SITE_RESOLVE || |
1276 | st->state==SITE_WAIT) { | |
1277 | /* We should definitely process it */ | |
1278 | if (process_msg1(st,buf,source)) { | |
1279 | slog(st,LOG_SETUP_INIT,"key setup initiated by peer"); | |
ff05a229 | 1280 | enter_new_state(st,SITE_SENTMSG2); |
2fe58dfd SE |
1281 | } else { |
1282 | slog(st,LOG_ERROR,"failed to process incoming msg1"); | |
1283 | } | |
1284 | BUF_FREE(buf); | |
1285 | return True; | |
ff05a229 | 1286 | } else if (st->state==SITE_SENTMSG1) { |
2fe58dfd SE |
1287 | /* We've just sent a message 1! They may have crossed on |
1288 | the wire. If we have priority then we ignore the | |
1289 | incoming one, otherwise we process it as usual. */ | |
1290 | if (st->setup_priority) { | |
1291 | BUF_FREE(buf); | |
1292 | slog(st,LOG_DUMP,"crossed msg1s; we are higher " | |
1293 | "priority => ignore incoming msg1"); | |
1294 | return True; | |
1295 | } else { | |
1296 | slog(st,LOG_DUMP,"crossed msg1s; we are lower " | |
1297 | "priority => use incoming msg1"); | |
1298 | if (process_msg1(st,buf,source)) { | |
1299 | BUF_FREE(&st->buffer); /* Free our old message 1 */ | |
ff05a229 | 1300 | enter_new_state(st,SITE_SENTMSG2); |
2fe58dfd SE |
1301 | } else { |
1302 | slog(st,LOG_ERROR,"failed to process an incoming " | |
1303 | "crossed msg1 (we have low priority)"); | |
1304 | } | |
1305 | BUF_FREE(buf); | |
1306 | return True; | |
1307 | } | |
1308 | } | |
1309 | /* The message 1 was received at an unexpected stage of the | |
1310 | key setup. XXX POLICY - what do we do? */ | |
1311 | slog(st,LOG_UNEXPECTED,"unexpected incoming message 1"); | |
1312 | BUF_FREE(buf); | |
1313 | return True; | |
1314 | } | |
1315 | return False; /* Not for us. */ | |
1316 | } | |
58650a70 | 1317 | if (dest==st->index) { |
2fe58dfd | 1318 | /* Explicitly addressed to us */ |
ff05a229 | 1319 | uint32_t msgtype=ntohl(get_uint32(buf->start+8)); |
2fe58dfd SE |
1320 | if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True); |
1321 | switch (msgtype) { | |
136740e6 | 1322 | case LABEL_NAK: |
794f2398 SE |
1323 | /* If the source is our current peer then initiate a key setup, |
1324 | because our peer's forgotten the key */ | |
19e9a588 | 1325 | if (get_uint32(buf->start+4)==st->current.remote_session_id) { |
794f2398 SE |
1326 | initiate_key_setup(st,"received a NAK"); |
1327 | } else { | |
1328 | slog(st,LOG_SEC,"bad incoming NAK"); | |
1329 | } | |
1330 | break; | |
2fe58dfd SE |
1331 | case LABEL_MSG0: |
1332 | process_msg0(st,buf,source); | |
1333 | break; | |
1334 | case LABEL_MSG1: | |
1335 | /* Setup packet: should not have been explicitly addressed | |
1336 | to us */ | |
59635212 | 1337 | slog(st,LOG_SEC,"incoming explicitly addressed msg1"); |
2fe58dfd SE |
1338 | break; |
1339 | case LABEL_MSG2: | |
1340 | /* Setup packet: expected only in state SENTMSG1 */ | |
1341 | if (st->state!=SITE_SENTMSG1) { | |
1342 | slog(st,LOG_UNEXPECTED,"unexpected MSG2"); | |
446353cd IJ |
1343 | } else if (process_msg2(st,buf,source)) { |
1344 | transport_setup_msgok(st,source); | |
ff05a229 | 1345 | enter_new_state(st,SITE_SENTMSG3); |
446353cd | 1346 | } else { |
59635212 | 1347 | slog(st,LOG_SEC,"invalid MSG2"); |
2fe58dfd SE |
1348 | } |
1349 | break; | |
1350 | case LABEL_MSG3: | |
1351 | /* Setup packet: expected only in state SENTMSG2 */ | |
1352 | if (st->state!=SITE_SENTMSG2) { | |
1353 | slog(st,LOG_UNEXPECTED,"unexpected MSG3"); | |
446353cd IJ |
1354 | } else if (process_msg3(st,buf,source)) { |
1355 | transport_setup_msgok(st,source); | |
ff05a229 | 1356 | enter_new_state(st,SITE_SENTMSG4); |
446353cd | 1357 | } else { |
59635212 | 1358 | slog(st,LOG_SEC,"invalid MSG3"); |
2fe58dfd SE |
1359 | } |
1360 | break; | |
1361 | case LABEL_MSG4: | |
1362 | /* Setup packet: expected only in state SENTMSG3 */ | |
1363 | if (st->state!=SITE_SENTMSG3) { | |
1364 | slog(st,LOG_UNEXPECTED,"unexpected MSG4"); | |
446353cd IJ |
1365 | } else if (process_msg4(st,buf,source)) { |
1366 | transport_setup_msgok(st,source); | |
ff05a229 | 1367 | enter_new_state(st,SITE_SENTMSG5); |
446353cd | 1368 | } else { |
59635212 | 1369 | slog(st,LOG_SEC,"invalid MSG4"); |
2fe58dfd SE |
1370 | } |
1371 | break; | |
1372 | case LABEL_MSG5: | |
4efd681a SE |
1373 | /* Setup packet: expected only in state SENTMSG4 */ |
1374 | /* (may turn up in state RUN if our return MSG6 was lost | |
1375 | and the new key has already been activated. In that | |
05f39b4d IJ |
1376 | case we discard it. The peer will realise that we |
1377 | are using the new key when they see our data packets. | |
1378 | Until then the peer's data packets to us get discarded. */ | |
c90cc2a7 IJ |
1379 | if (st->state==SITE_SENTMSG4) { |
1380 | if (process_msg5(st,buf,source,st->new_transform)) { | |
1381 | transport_setup_msgok(st,source); | |
1382 | enter_new_state(st,SITE_RUN); | |
1383 | } else { | |
1384 | slog(st,LOG_SEC,"invalid MSG5"); | |
1385 | } | |
1386 | } else if (st->state==SITE_RUN) { | |
19e9a588 | 1387 | if (process_msg5(st,buf,source,st->current.transform)) { |
c90cc2a7 IJ |
1388 | slog(st,LOG_DROP,"got MSG5, retransmitting MSG6"); |
1389 | transport_setup_msgok(st,source); | |
19e9a588 IJ |
1390 | create_msg6(st,st->current.transform, |
1391 | st->current.remote_session_id); | |
c90cc2a7 IJ |
1392 | transport_xmit(st,&st->peers,&st->buffer,True); |
1393 | BUF_FREE(&st->buffer); | |
1394 | } else { | |
1395 | slog(st,LOG_SEC,"invalid MSG5 (in state RUN)"); | |
1396 | } | |
2fe58dfd | 1397 | } else { |
c90cc2a7 | 1398 | slog(st,LOG_UNEXPECTED,"unexpected MSG5"); |
2fe58dfd SE |
1399 | } |
1400 | break; | |
1401 | case LABEL_MSG6: | |
1402 | /* Setup packet: expected only in state SENTMSG5 */ | |
1403 | if (st->state!=SITE_SENTMSG5) { | |
1404 | slog(st,LOG_UNEXPECTED,"unexpected MSG6"); | |
1405 | } else if (process_msg6(st,buf,source)) { | |
1406 | BUF_FREE(&st->buffer); /* Free message 5 */ | |
446353cd | 1407 | transport_setup_msgok(st,source); |
2fe58dfd SE |
1408 | activate_new_key(st); |
1409 | } else { | |
59635212 | 1410 | slog(st,LOG_SEC,"invalid MSG6"); |
2fe58dfd SE |
1411 | } |
1412 | break; | |
2fe58dfd | 1413 | default: |
59635212 | 1414 | slog(st,LOG_SEC,"received message of unknown type 0x%08x", |
2fe58dfd SE |
1415 | msgtype); |
1416 | break; | |
1417 | } | |
1418 | BUF_FREE(buf); | |
1419 | return True; | |
1420 | } | |
1421 | ||
1422 | return False; | |
1423 | } | |
1424 | ||
1425 | static void site_control(void *vst, bool_t run) | |
1426 | { | |
1427 | struct site *st=vst; | |
1428 | if (run) enter_state_run(st); | |
1429 | else enter_state_stop(st); | |
1430 | } | |
1431 | ||
794f2398 SE |
1432 | static void site_phase_hook(void *sst, uint32_t newphase) |
1433 | { | |
1434 | struct site *st=sst; | |
1435 | ||
1436 | /* The program is shutting down; tell our peer */ | |
1437 | send_msg7(st,"shutting down"); | |
1438 | } | |
1439 | ||
2fe58dfd SE |
1440 | static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context, |
1441 | list_t *args) | |
1442 | { | |
58650a70 | 1443 | static uint32_t index_sequence; |
2fe58dfd SE |
1444 | struct site *st; |
1445 | item_t *item; | |
1446 | dict_t *dict; | |
59533c16 | 1447 | int i; |
2fe58dfd SE |
1448 | |
1449 | st=safe_malloc(sizeof(*st),"site_apply"); | |
1450 | ||
1451 | st->cl.description="site"; | |
1452 | st->cl.type=CL_SITE; | |
1453 | st->cl.apply=NULL; | |
1454 | st->cl.interface=&st->ops; | |
1455 | st->ops.st=st; | |
1456 | st->ops.control=site_control; | |
1457 | st->ops.status=site_status; | |
1458 | ||
1459 | /* First parameter must be a dict */ | |
1460 | item=list_elem(args,0); | |
1461 | if (!item || item->type!=t_dict) | |
1462 | cfgfatal(loc,"site","parameter must be a dictionary\n"); | |
1463 | ||
1464 | dict=item->data.dict; | |
558fa3fb SE |
1465 | st->localname=dict_read_string(dict, "local-name", True, "site", loc); |
1466 | st->remotename=dict_read_string(dict, "name", True, "site", loc); | |
dba19f84 IJ |
1467 | |
1468 | st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False); | |
1469 | bool_t local_mobile= | |
1470 | dict_read_bool(dict,"local-mobile",False,"site",loc,False); | |
1471 | ||
558fa3fb SE |
1472 | /* Sanity check (which also allows the 'sites' file to include |
1473 | site() closures for all sites including our own): refuse to | |
1474 | talk to ourselves */ | |
1475 | if (strcmp(st->localname,st->remotename)==0) { | |
b2a56f7c | 1476 | Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n", |
baa06aeb | 1477 | st->localname); |
dba19f84 IJ |
1478 | if (st->peer_mobile != local_mobile) |
1479 | cfgfatal(loc,"site","site %s's peer-mobile=%d" | |
1480 | " but our local-mobile=%d\n", | |
1481 | st->localname, st->peer_mobile, local_mobile); | |
1482 | free(st); | |
1483 | return NULL; | |
1484 | } | |
1485 | if (st->peer_mobile && local_mobile) { | |
1486 | Message(M_WARNING,"site %s: site is mobile but so are we" | |
1487 | " -> ignoring this site\n", st->remotename); | |
558fa3fb SE |
1488 | free(st); |
1489 | return NULL; | |
1490 | } | |
dba19f84 | 1491 | |
58650a70 RK |
1492 | assert(index_sequence < 0xffffffffUL); |
1493 | st->index = ++index_sequence; | |
469fd1d9 | 1494 | st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc); |
59533c16 IJ |
1495 | |
1496 | list_t *comms_cfg=dict_lookup(dict,"comm"); | |
39a6b1e2 | 1497 | if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n"); |
59533c16 IJ |
1498 | st->ncomms=list_length(comms_cfg); |
1499 | st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms"); | |
1500 | assert(st->ncomms); | |
1501 | for (i=0; i<st->ncomms; i++) { | |
1502 | item_t *item=list_elem(comms_cfg,i); | |
39a6b1e2 IJ |
1503 | if (item->type!=t_closure) |
1504 | cfgfatal(loc,"site","comm is not a closure\n"); | |
59533c16 | 1505 | closure_t *cl=item->data.closure; |
39a6b1e2 | 1506 | if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n"); |
59533c16 IJ |
1507 | st->comms[i]=cl->interface; |
1508 | } | |
1509 | ||
2fe58dfd SE |
1510 | st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc); |
1511 | st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc); | |
1512 | st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc); | |
1513 | ||
2fe58dfd | 1514 | st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc); |
2fe58dfd | 1515 | st->address=dict_read_string(dict, "address", False, "site", loc); |
3454dce4 SE |
1516 | if (st->address) |
1517 | st->remoteport=dict_read_number(dict,"port",True,"site",loc,0); | |
1518 | else st->remoteport=0; | |
2fe58dfd SE |
1519 | st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc); |
1520 | ||
1521 | st->transform= | |
1522 | find_cl_if(dict,"transform",CL_TRANSFORM,True,"site",loc); | |
1523 | ||
1524 | st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc); | |
1525 | st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc); | |
1526 | ||
e57264d6 IJ |
1527 | #define DEFAULT(D) (st->peer_mobile || local_mobile \ |
1528 | ? DEFAULT_MOBILE_##D : DEFAULT_##D) | |
e7f8ec2a | 1529 | #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D)); |
c27ca22f | 1530 | |
e7f8ec2a IJ |
1531 | st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME); |
1532 | st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES); | |
1533 | st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL); | |
1534 | st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME); | |
1535 | ||
446353cd IJ |
1536 | st->mobile_peer_expiry= dict_read_number( |
1537 | dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY); | |
1538 | ||
1539 | st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number( | |
1540 | dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX); | |
1541 | if (st->transport_peers_max<1 || | |
1542 | st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) { | |
1543 | cfgfatal(loc,"site","mobile-peers-max must be in range 1.." | |
1544 | STRING(MAX_MOBILE_PEERS_MAX) "\n"); | |
1545 | } | |
1546 | ||
e7f8ec2a | 1547 | if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2) |
c27ca22f IJ |
1548 | st->key_renegotiate_time=st->key_lifetime/2; |
1549 | else | |
e7f8ec2a | 1550 | st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP); |
9d3a4132 | 1551 | st->key_renegotiate_time=dict_read_number( |
cce0051f | 1552 | dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time); |
9d3a4132 SE |
1553 | if (st->key_renegotiate_time > st->key_lifetime) { |
1554 | cfgfatal(loc,"site", | |
1555 | "renegotiate-time must be less than key-lifetime\n"); | |
1556 | } | |
9d3a4132 SE |
1557 | |
1558 | st->log_events=string_list_to_word(dict_lookup(dict,"log-events"), | |
1559 | log_event_table,"site"); | |
2fe58dfd | 1560 | |
4efd681a SE |
1561 | st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5, |
1562 | "site_apply"); | |
1563 | sprintf(st->tunname,"%s<->%s",st->localname,st->remotename); | |
1564 | ||
2fe58dfd | 1565 | /* The information we expect to see in incoming messages of type 1 */ |
59230b9b IJ |
1566 | /* fixme: lots of unchecked overflows here, but the results are only |
1567 | corrupted packets rather than undefined behaviour */ | |
2fe58dfd SE |
1568 | st->setupsiglen=strlen(st->remotename)+strlen(st->localname)+8; |
1569 | st->setupsig=safe_malloc(st->setupsiglen,"site_apply"); | |
8689b3a9 SE |
1570 | put_uint32(st->setupsig+0,LABEL_MSG1); |
1571 | put_uint16(st->setupsig+4,strlen(st->remotename)); | |
2fe58dfd | 1572 | memcpy(&st->setupsig[6],st->remotename,strlen(st->remotename)); |
8689b3a9 | 1573 | put_uint16(st->setupsig+(6+strlen(st->remotename)),strlen(st->localname)); |
2fe58dfd SE |
1574 | memcpy(&st->setupsig[8+strlen(st->remotename)],st->localname, |
1575 | strlen(st->localname)); | |
1576 | st->setup_priority=(strcmp(st->localname,st->remotename)>0); | |
1577 | ||
1578 | buffer_new(&st->buffer,SETUP_BUFFER_LEN); | |
1579 | ||
05f39b4d IJ |
1580 | buffer_new(&st->scratch,0); |
1581 | BUF_ALLOC(&st->scratch,"site:scratch"); | |
1582 | ||
2fe58dfd SE |
1583 | /* We are interested in poll(), but only for timeouts. We don't have |
1584 | any fds of our own. */ | |
1585 | register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site"); | |
1586 | st->timeout=0; | |
1587 | ||
19e9a588 | 1588 | st->current.key_timeout=0; |
02b0959b | 1589 | st->auxiliary_key.key_timeout=0; |
446353cd IJ |
1590 | transport_peers_clear(st,&st->peers); |
1591 | transport_peers_clear(st,&st->setup_peers); | |
2fe58dfd SE |
1592 | /* XXX mlock these */ |
1593 | st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret"); | |
7c9ca4bd IJ |
1594 | st->sharedsecretlen=st->transform->keylen?:st->dh->ceil_len; |
1595 | st->sharedsecret=safe_malloc(st->sharedsecretlen,"site:sharedsecret"); | |
2fe58dfd | 1596 | |
59533c16 IJ |
1597 | /* We need to compute some properties of our comms */ |
1598 | #define COMPUTE_WORST(pad) \ | |
1599 | int worst_##pad=0; \ | |
1600 | for (i=0; i<st->ncomms; i++) { \ | |
1601 | int thispad=st->comms[i]->pad; \ | |
1602 | if (thispad > worst_##pad) \ | |
1603 | worst_##pad=thispad; \ | |
1604 | } | |
1605 | COMPUTE_WORST(min_start_pad) | |
1606 | COMPUTE_WORST(min_end_pad) | |
1607 | ||
2fe58dfd | 1608 | /* We need to register the remote networks with the netlink device */ |
469fd1d9 | 1609 | st->netlink->reg(st->netlink->st, site_outgoing, st, |
ff05a229 | 1610 | st->transform->max_start_pad+(4*4)+ |
59533c16 IJ |
1611 | worst_min_start_pad, |
1612 | st->transform->max_end_pad+worst_min_end_pad); | |
ff05a229 | 1613 | |
59533c16 IJ |
1614 | for (i=0; i<st->ncomms; i++) |
1615 | st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming); | |
2fe58dfd | 1616 | |
19e9a588 | 1617 | st->current.transform=st->transform->create(st->transform->st); |
02b0959b | 1618 | st->auxiliary_key.transform=st->transform->create(st->transform->st); |
2fe58dfd | 1619 | st->new_transform=st->transform->create(st->transform->st); |
bd98cd6b | 1620 | st->auxiliary_is_new=0; |
2fe58dfd SE |
1621 | |
1622 | enter_state_stop(st); | |
1623 | ||
794f2398 SE |
1624 | add_hook(PHASE_SHUTDOWN,site_phase_hook,st); |
1625 | ||
2fe58dfd SE |
1626 | return new_closure(&st->cl); |
1627 | } | |
1628 | ||
2fe58dfd SE |
1629 | void site_module(dict_t *dict) |
1630 | { | |
1631 | add_closure(dict,"site",site_apply); | |
1632 | } | |
446353cd IJ |
1633 | |
1634 | ||
1635 | /***** TRANSPORT PEERS definitions *****/ | |
1636 | ||
1637 | static void transport_peers_debug(struct site *st, transport_peers *dst, | |
1638 | const char *didwhat, | |
1639 | int nargs, const struct comm_addr *args, | |
1640 | size_t stride) { | |
1641 | int i; | |
1642 | char *argp; | |
1643 | ||
1644 | if (!(st->log_events & LOG_PEER_ADDRS)) | |
1645 | return; /* an optimisation */ | |
1646 | ||
1647 | slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d", | |
1648 | (dst==&st->peers ? "data" : | |
1649 | dst==&st->setup_peers ? "setup" : "UNKNOWN"), | |
1650 | didwhat, nargs, dst->npeers); | |
1651 | ||
1652 | for (i=0, argp=(void*)args; | |
1653 | i<nargs; | |
1654 | i++, (argp+=stride?stride:sizeof(*args))) { | |
1655 | const struct comm_addr *ca=(void*)argp; | |
1656 | slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s", | |
1657 | i, ca->comm->addr_to_string(ca->comm->st,ca)); | |
1658 | } | |
1659 | for (i=0; i<dst->npeers; i++) { | |
1660 | struct timeval diff; | |
1661 | timersub(tv_now,&dst->peers[i].last,&diff); | |
1662 | const struct comm_addr *ca=&dst->peers[i].addr; | |
1663 | slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld", | |
1664 | i, ca->comm->addr_to_string(ca->comm->st,ca), | |
1665 | (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec); | |
1666 | } | |
1667 | } | |
1668 | ||
1669 | static int transport_peer_compar(const void *av, const void *bv) { | |
1670 | const transport_peer *a=av; | |
1671 | const transport_peer *b=bv; | |
1672 | /* put most recent first in the array */ | |
1673 | if (timercmp(&a->last, &b->last, <)) return +1; | |
1674 | if (timercmp(&a->last, &b->last, >)) return -11; | |
1675 | return 0; | |
1676 | } | |
1677 | ||
1678 | static void transport_peers_expire(struct site *st, transport_peers *peers) { | |
1679 | /* peers must be sorted first */ | |
1680 | int previous_peers=peers->npeers; | |
1681 | struct timeval oldest; | |
1682 | oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry; | |
1683 | oldest.tv_usec = tv_now->tv_usec; | |
1684 | while (peers->npeers>1 && | |
1685 | timercmp(&peers->peers[peers->npeers-1].last, &oldest, <)) | |
1686 | peers->npeers--; | |
1687 | if (peers->npeers != previous_peers) | |
1688 | transport_peers_debug(st,peers,"expire", 0,0,0); | |
1689 | } | |
1690 | ||
1691 | static void transport_record_peer(struct site *st, transport_peers *peers, | |
1692 | const struct comm_addr *addr, const char *m) { | |
1693 | int slot, changed=0; | |
1694 | ||
1695 | for (slot=0; slot<peers->npeers; slot++) | |
1696 | if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr))) | |
1697 | goto found; | |
1698 | ||
1699 | changed=1; | |
1700 | if (peers->npeers==st->transport_peers_max) | |
1701 | slot=st->transport_peers_max; | |
1702 | else | |
1703 | slot=peers->npeers++; | |
1704 | ||
1705 | found: | |
1706 | peers->peers[slot].addr=*addr; | |
1707 | peers->peers[slot].last=*tv_now; | |
1708 | ||
1709 | if (peers->npeers>1) | |
1710 | qsort(peers->peers, peers->npeers, | |
1711 | sizeof(*peers->peers), transport_peer_compar); | |
1712 | ||
1713 | if (changed || peers->npeers!=1) | |
1714 | transport_peers_debug(st,peers,m, 1,addr,0); | |
1715 | transport_peers_expire(st, peers); | |
1716 | } | |
1717 | ||
1718 | static bool_t transport_compute_setupinit_peers(struct site *st, | |
1719 | const struct comm_addr *configured_addr /* 0 if none or not found */) { | |
1720 | ||
1721 | if (!configured_addr && !transport_peers_valid(&st->peers)) | |
1722 | return False; | |
1723 | ||
1724 | slog(st,LOG_SETUP_INIT, | |
1725 | (!configured_addr ? "using only %d old peer address(es)" | |
1726 | : "using configured address, and/or perhaps %d old peer address(es)"), | |
1727 | st->peers); | |
1728 | ||
1729 | /* Non-mobile peers havve st->peers.npeers==0 or ==1, since they | |
1730 | * have transport_peers_max==1. The effect is that this code | |
1731 | * always uses the configured address if supplied, or otherwise | |
1732 | * the existing data peer if one exists; this is as desired. */ | |
1733 | ||
1734 | transport_peers_copy(st,&st->setup_peers,&st->peers); | |
1735 | ||
1736 | if (configured_addr) | |
1737 | transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit"); | |
1738 | ||
1739 | assert(transport_peers_valid(&st->setup_peers)); | |
1740 | return True; | |
1741 | } | |
1742 | ||
1743 | static void transport_setup_msgok(struct site *st, const struct comm_addr *a) { | |
1744 | if (st->peer_mobile) | |
1745 | transport_record_peer(st,&st->setup_peers,a,"setupmsg"); | |
1746 | } | |
1747 | static void transport_data_msgok(struct site *st, const struct comm_addr *a) { | |
1748 | if (st->peer_mobile) | |
1749 | transport_record_peer(st,&st->peers,a,"datamsg"); | |
1750 | } | |
1751 | ||
1752 | static int transport_peers_valid(transport_peers *peers) { | |
1753 | return peers->npeers; | |
1754 | } | |
1755 | static void transport_peers_clear(struct site *st, transport_peers *peers) { | |
1756 | peers->npeers= 0; | |
1757 | transport_peers_debug(st,peers,"clear",0,0,0); | |
1758 | } | |
1759 | static void transport_peers_copy(struct site *st, transport_peers *dst, | |
1760 | const transport_peers *src) { | |
1761 | dst->npeers=src->npeers; | |
1762 | memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers); | |
1763 | transport_peers_debug(st,dst,"copy", | |
a620a048 | 1764 | src->npeers, &src->peers->addr, sizeof(*src->peers)); |
446353cd IJ |
1765 | } |
1766 | ||
1767 | void transport_xmit(struct site *st, transport_peers *peers, | |
1768 | struct buffer_if *buf, bool_t candebug) { | |
1769 | int slot; | |
1770 | transport_peers_expire(st, peers); | |
1771 | for (slot=0; slot<peers->npeers; slot++) { | |
1772 | transport_peer *peer=&peers->peers[slot]; | |
1773 | if (candebug) | |
1774 | dump_packet(st, buf, &peer->addr, False); | |
1775 | peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr); | |
1776 | } | |
1777 | } | |
1778 | ||
1779 | /***** END of transport peers declarations *****/ |