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 | 255 | |
2fe58dfd SE |
256 | bool_t setup_priority; /* Do we have precedence if both sites emit |
257 | message 1 simultaneously? */ | |
258 | uint32_t log_events; | |
259 | ||
260 | /* runtime information */ | |
261 | uint32_t state; | |
262 | uint64_t now; /* Most recently seen time */ | |
263 | ||
ff05a229 | 264 | /* The currently established session */ |
19e9a588 | 265 | struct data_key current; |
02b0959b | 266 | struct data_key auxiliary_key; |
bd98cd6b | 267 | bool_t auxiliary_is_new; |
ff05a229 | 268 | uint64_t renegotiate_key_time; /* When we can negotiate a new key */ |
bd98cd6b | 269 | uint64_t auxiliary_renegotiate_key_time; |
446353cd | 270 | transport_peers peers; /* Current address(es) of peer for data traffic */ |
2fe58dfd | 271 | |
ff05a229 SE |
272 | /* The current key setup protocol exchange. We can only be |
273 | involved in one of these at a time. There's a potential for | |
274 | denial of service here (the attacker keeps sending a setup | |
275 | packet; we keep trying to continue the exchange, and have to | |
276 | timeout before we can listen for another setup packet); perhaps | |
277 | we should keep a list of 'bad' sources for setup packets. */ | |
2fe58dfd | 278 | uint32_t setup_session_id; |
446353cd | 279 | transport_peers setup_peers; |
2fe58dfd SE |
280 | uint8_t localN[NONCELEN]; /* Nonces for key exchange */ |
281 | uint8_t remoteN[NONCELEN]; | |
282 | struct buffer_if buffer; /* Current outgoing key exchange packet */ | |
05f39b4d | 283 | struct buffer_if scratch; |
4a8aed08 | 284 | int32_t retries; /* Number of retries remaining */ |
2fe58dfd SE |
285 | uint64_t timeout; /* Timeout for current state */ |
286 | uint8_t *dhsecret; | |
287 | uint8_t *sharedsecret; | |
7c9ca4bd | 288 | uint32_t sharedsecretlen; |
2fe58dfd SE |
289 | struct transform_inst_if *new_transform; /* For key setup/verify */ |
290 | }; | |
291 | ||
fe5e9cc4 | 292 | static void slog(struct site *st, uint32_t event, cstring_t msg, ...) |
2fe58dfd SE |
293 | { |
294 | va_list ap; | |
7c006408 | 295 | char buf[240]; |
b2a56f7c | 296 | uint32_t class; |
2fe58dfd SE |
297 | |
298 | va_start(ap,msg); | |
299 | ||
300 | if (event&st->log_events) { | |
b2a56f7c SE |
301 | switch(event) { |
302 | case LOG_UNEXPECTED: class=M_INFO; break; | |
303 | case LOG_SETUP_INIT: class=M_INFO; break; | |
304 | case LOG_SETUP_TIMEOUT: class=M_NOTICE; break; | |
305 | case LOG_ACTIVATE_KEY: class=M_INFO; break; | |
306 | case LOG_TIMEOUT_KEY: class=M_INFO; break; | |
307 | case LOG_SEC: class=M_SECURITY; break; | |
308 | case LOG_STATE: class=M_DEBUG; break; | |
309 | case LOG_DROP: class=M_DEBUG; break; | |
310 | case LOG_DUMP: class=M_DEBUG; break; | |
469fd1d9 | 311 | case LOG_ERROR: class=M_ERR; break; |
446353cd | 312 | case LOG_PEER_ADDRS: class=M_DEBUG; break; |
469fd1d9 | 313 | default: class=M_ERR; break; |
b2a56f7c SE |
314 | } |
315 | ||
c1d2109a | 316 | vsnprintf(buf,sizeof(buf),msg,ap); |
b2a56f7c | 317 | st->log->log(st->log->st,class,"%s: %s",st->tunname,buf); |
2fe58dfd SE |
318 | } |
319 | va_end(ap); | |
320 | } | |
321 | ||
9d3a4132 | 322 | static void set_link_quality(struct site *st); |
1d388569 IJ |
323 | static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel); |
324 | static void delete_one_key(struct site *st, struct data_key *key, | |
325 | const char *reason /* may be 0 meaning don't log*/, | |
326 | const char *which /* ignored if !reasonn */, | |
327 | uint32_t loglevel /* ignored if !reasonn */); | |
fe5e9cc4 | 328 | static bool_t initiate_key_setup(struct site *st, cstring_t reason); |
2fe58dfd SE |
329 | static void enter_state_run(struct site *st); |
330 | static bool_t enter_state_resolve(struct site *st); | |
ff05a229 | 331 | static bool_t enter_new_state(struct site *st,uint32_t next); |
2fe58dfd | 332 | static void enter_state_wait(struct site *st); |
05f39b4d | 333 | static void activate_new_key(struct site *st); |
2fe58dfd | 334 | |
3d8d8f4e IJ |
335 | static bool_t current_valid(struct site *st) |
336 | { | |
19e9a588 | 337 | return st->current.transform->valid(st->current.transform->st); |
3d8d8f4e IJ |
338 | } |
339 | ||
2fe58dfd SE |
340 | #define CHECK_AVAIL(b,l) do { if ((b)->size<(l)) return False; } while(0) |
341 | #define CHECK_EMPTY(b) do { if ((b)->size!=0) return False; } while(0) | |
342 | #define CHECK_TYPE(b,t) do { uint32_t type; \ | |
343 | CHECK_AVAIL((b),4); \ | |
59635212 | 344 | type=buf_unprepend_uint32((b)); \ |
2fe58dfd SE |
345 | if (type!=(t)) return False; } while(0) |
346 | ||
1737eeef IJ |
347 | struct parsedname { |
348 | int32_t len; | |
349 | uint8_t *name; | |
350 | int32_t extrainfo_len; | |
351 | uint8_t *extrainfo; | |
352 | }; | |
353 | ||
2fe58dfd SE |
354 | struct msg { |
355 | uint8_t *hashstart; | |
356 | uint32_t dest; | |
357 | uint32_t source; | |
1737eeef IJ |
358 | struct parsedname remote; |
359 | struct parsedname local; | |
2fe58dfd SE |
360 | uint8_t *nR; |
361 | uint8_t *nL; | |
1caa23ff | 362 | int32_t pklen; |
3e8addad | 363 | char *pk; |
1caa23ff IJ |
364 | int32_t hashlen; |
365 | int32_t siglen; | |
3e8addad | 366 | char *sig; |
2fe58dfd SE |
367 | }; |
368 | ||
ff05a229 SE |
369 | /* Build any of msg1 to msg4. msg5 and msg6 are built from the inside |
370 | out using a transform of config data supplied by netlink */ | |
fe5e9cc4 | 371 | static bool_t generate_msg(struct site *st, uint32_t type, cstring_t what) |
2fe58dfd SE |
372 | { |
373 | void *hst; | |
3b83c932 | 374 | uint8_t *hash; |
2fe58dfd SE |
375 | string_t dhpub, sig; |
376 | ||
377 | st->retries=st->setup_retries; | |
378 | BUF_ALLOC(&st->buffer,what); | |
379 | buffer_init(&st->buffer,0); | |
59635212 SE |
380 | buf_append_uint32(&st->buffer, |
381 | (type==LABEL_MSG1?0:st->setup_session_id)); | |
58650a70 | 382 | buf_append_uint32(&st->buffer,st->index); |
59635212 | 383 | buf_append_uint32(&st->buffer,type); |
2fe58dfd SE |
384 | buf_append_string(&st->buffer,st->localname); |
385 | buf_append_string(&st->buffer,st->remotename); | |
386 | memcpy(buf_append(&st->buffer,NONCELEN),st->localN,NONCELEN); | |
387 | if (type==LABEL_MSG1) return True; | |
388 | memcpy(buf_append(&st->buffer,NONCELEN),st->remoteN,NONCELEN); | |
389 | if (type==LABEL_MSG2) return True; | |
3b83c932 SE |
390 | |
391 | if (hacky_par_mid_failnow()) return False; | |
392 | ||
2fe58dfd SE |
393 | dhpub=st->dh->makepublic(st->dh->st,st->dhsecret,st->dh->len); |
394 | buf_append_string(&st->buffer,dhpub); | |
395 | free(dhpub); | |
3b83c932 | 396 | hash=safe_malloc(st->hash->len, "generate_msg"); |
2fe58dfd SE |
397 | hst=st->hash->init(); |
398 | st->hash->update(hst,st->buffer.start,st->buffer.size); | |
399 | st->hash->final(hst,hash); | |
400 | sig=st->privkey->sign(st->privkey->st,hash,st->hash->len); | |
401 | buf_append_string(&st->buffer,sig); | |
402 | free(sig); | |
3b83c932 | 403 | free(hash); |
2fe58dfd SE |
404 | return True; |
405 | } | |
406 | ||
1737eeef IJ |
407 | static bool_t unpick_name(struct buffer_if *msg, struct parsedname *nm) |
408 | { | |
409 | CHECK_AVAIL(msg,2); | |
410 | nm->len=buf_unprepend_uint16(msg); | |
411 | CHECK_AVAIL(msg,nm->len); | |
412 | nm->name=buf_unprepend(msg,nm->len); | |
413 | uint8_t *nul=memchr(nm->name,0,nm->len); | |
414 | if (!nul) { | |
415 | nm->extrainfo_len=0; | |
416 | nm->extrainfo=0; | |
417 | } else { | |
418 | nm->extrainfo=nul+1; | |
419 | nm->extrainfo_len=msg->start-nm->extrainfo; | |
420 | nm->len=nul-nm->name; | |
421 | } | |
422 | return True; | |
423 | } | |
424 | ||
2fe58dfd SE |
425 | static bool_t unpick_msg(struct site *st, uint32_t type, |
426 | struct buffer_if *msg, struct msg *m) | |
427 | { | |
428 | m->hashstart=msg->start; | |
429 | CHECK_AVAIL(msg,4); | |
59635212 | 430 | m->dest=buf_unprepend_uint32(msg); |
2fe58dfd | 431 | CHECK_AVAIL(msg,4); |
59635212 | 432 | m->source=buf_unprepend_uint32(msg); |
2fe58dfd | 433 | CHECK_TYPE(msg,type); |
1737eeef IJ |
434 | if (!unpick_name(msg,&m->remote)) return False; |
435 | if (!unpick_name(msg,&m->local)) return False; | |
2fe58dfd SE |
436 | CHECK_AVAIL(msg,NONCELEN); |
437 | m->nR=buf_unprepend(msg,NONCELEN); | |
438 | if (type==LABEL_MSG1) { | |
439 | CHECK_EMPTY(msg); | |
440 | return True; | |
441 | } | |
442 | CHECK_AVAIL(msg,NONCELEN); | |
443 | m->nL=buf_unprepend(msg,NONCELEN); | |
444 | if (type==LABEL_MSG2) { | |
445 | CHECK_EMPTY(msg); | |
446 | return True; | |
447 | } | |
448 | CHECK_AVAIL(msg,2); | |
59635212 | 449 | m->pklen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
450 | CHECK_AVAIL(msg,m->pklen); |
451 | m->pk=buf_unprepend(msg,m->pklen); | |
452 | m->hashlen=msg->start-m->hashstart; | |
453 | CHECK_AVAIL(msg,2); | |
59635212 | 454 | m->siglen=buf_unprepend_uint16(msg); |
2fe58dfd SE |
455 | CHECK_AVAIL(msg,m->siglen); |
456 | m->sig=buf_unprepend(msg,m->siglen); | |
457 | CHECK_EMPTY(msg); | |
458 | return True; | |
459 | } | |
460 | ||
1737eeef IJ |
461 | static bool_t name_matches(const struct parsedname *nm, const char *expected) |
462 | { | |
463 | int expected_len=strlen(expected); | |
464 | return | |
465 | nm->len == expected_len && | |
466 | !memcmp(nm->name, expected, expected_len); | |
467 | } | |
468 | ||
ff05a229 | 469 | static bool_t check_msg(struct site *st, uint32_t type, struct msg *m, |
fe5e9cc4 | 470 | cstring_t *error) |
ff05a229 SE |
471 | { |
472 | if (type==LABEL_MSG1) return True; | |
473 | ||
474 | /* Check that the site names and our nonce have been sent | |
475 | back correctly, and then store our peer's nonce. */ | |
1737eeef | 476 | if (!name_matches(&m->remote,st->remotename)) { |
ff05a229 SE |
477 | *error="wrong remote site name"; |
478 | return False; | |
479 | } | |
1737eeef | 480 | if (!name_matches(&m->local,st->localname)) { |
ff05a229 SE |
481 | *error="wrong local site name"; |
482 | return False; | |
483 | } | |
484 | if (memcmp(m->nL,st->localN,NONCELEN)!=0) { | |
485 | *error="wrong locally-generated nonce"; | |
486 | return False; | |
487 | } | |
488 | if (type==LABEL_MSG2) return True; | |
5ad34db2 | 489 | if (!consttime_memeq(m->nR,st->remoteN,NONCELEN)!=0) { |
ff05a229 SE |
490 | *error="wrong remotely-generated nonce"; |
491 | return False; | |
492 | } | |
493 | if (type==LABEL_MSG3) return True; | |
494 | if (type==LABEL_MSG4) return True; | |
495 | *error="unknown message type"; | |
496 | return False; | |
497 | } | |
498 | ||
2fe58dfd SE |
499 | static bool_t generate_msg1(struct site *st) |
500 | { | |
501 | st->random->generate(st->random->st,NONCELEN,st->localN); | |
502 | return generate_msg(st,LABEL_MSG1,"site:MSG1"); | |
503 | } | |
504 | ||
505 | static bool_t process_msg1(struct site *st, struct buffer_if *msg1, | |
7e29719e | 506 | const struct comm_addr *src, struct msg *m) |
2fe58dfd | 507 | { |
2fe58dfd SE |
508 | /* We've already determined we're in an appropriate state to |
509 | process an incoming MSG1, and that the MSG1 has correct values | |
510 | of A and B. */ | |
511 | ||
446353cd | 512 | transport_record_peer(st,&st->setup_peers,src,"msg1"); |
7e29719e IJ |
513 | st->setup_session_id=m->source; |
514 | memcpy(st->remoteN,m->nR,NONCELEN); | |
2fe58dfd SE |
515 | return True; |
516 | } | |
517 | ||
518 | static bool_t generate_msg2(struct site *st) | |
519 | { | |
520 | st->random->generate(st->random->st,NONCELEN,st->localN); | |
521 | return generate_msg(st,LABEL_MSG2,"site:MSG2"); | |
522 | } | |
523 | ||
524 | static bool_t process_msg2(struct site *st, struct buffer_if *msg2, | |
a15faeb2 | 525 | const struct comm_addr *src) |
2fe58dfd SE |
526 | { |
527 | struct msg m; | |
fe5e9cc4 | 528 | cstring_t err; |
2fe58dfd SE |
529 | |
530 | if (!unpick_msg(st,LABEL_MSG2,msg2,&m)) return False; | |
ff05a229 SE |
531 | if (!check_msg(st,LABEL_MSG2,&m,&err)) { |
532 | slog(st,LOG_SEC,"msg2: %s",err); | |
2fe58dfd SE |
533 | return False; |
534 | } | |
535 | st->setup_session_id=m.source; | |
536 | memcpy(st->remoteN,m.nR,NONCELEN); | |
537 | return True; | |
538 | } | |
539 | ||
540 | static bool_t generate_msg3(struct site *st) | |
541 | { | |
542 | /* Now we have our nonce and their nonce. Think of a secret key, | |
543 | and create message number 3. */ | |
544 | st->random->generate(st->random->st,st->dh->len,st->dhsecret); | |
545 | return generate_msg(st,LABEL_MSG3,"site:MSG3"); | |
546 | } | |
547 | ||
548 | static bool_t process_msg3(struct site *st, struct buffer_if *msg3, | |
a15faeb2 | 549 | const struct comm_addr *src) |
2fe58dfd SE |
550 | { |
551 | struct msg m; | |
3b83c932 | 552 | uint8_t *hash; |
2fe58dfd | 553 | void *hst; |
fe5e9cc4 | 554 | cstring_t err; |
2fe58dfd SE |
555 | |
556 | if (!unpick_msg(st,LABEL_MSG3,msg3,&m)) return False; | |
ff05a229 SE |
557 | if (!check_msg(st,LABEL_MSG3,&m,&err)) { |
558 | slog(st,LOG_SEC,"msg3: %s",err); | |
2fe58dfd SE |
559 | return False; |
560 | } | |
ff05a229 | 561 | |
2fe58dfd | 562 | /* Check signature and store g^x mod m */ |
3b83c932 | 563 | hash=safe_malloc(st->hash->len, "process_msg3"); |
2fe58dfd SE |
564 | hst=st->hash->init(); |
565 | st->hash->update(hst,m.hashstart,m.hashlen); | |
566 | st->hash->final(hst,hash); | |
567 | /* Terminate signature with a '0' - cheating, but should be ok */ | |
568 | m.sig[m.siglen]=0; | |
569 | if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) { | |
59635212 | 570 | slog(st,LOG_SEC,"msg3 signature failed check!"); |
3b83c932 | 571 | free(hash); |
2fe58dfd SE |
572 | return False; |
573 | } | |
3b83c932 | 574 | free(hash); |
2fe58dfd SE |
575 | |
576 | /* Terminate their DH public key with a '0' */ | |
577 | m.pk[m.pklen]=0; | |
578 | /* Invent our DH secret key */ | |
579 | st->random->generate(st->random->st,st->dh->len,st->dhsecret); | |
580 | ||
581 | /* Generate the shared key */ | |
582 | st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk, | |
7c9ca4bd | 583 | st->sharedsecret,st->sharedsecretlen); |
2fe58dfd SE |
584 | |
585 | /* Set up the transform */ | |
586 | st->new_transform->setkey(st->new_transform->st,st->sharedsecret, | |
0118121a | 587 | st->sharedsecretlen,st->setup_priority); |
2fe58dfd SE |
588 | |
589 | return True; | |
590 | } | |
591 | ||
592 | static bool_t generate_msg4(struct site *st) | |
593 | { | |
594 | /* We have both nonces, their public key and our private key. Generate | |
595 | our public key, sign it and send it to them. */ | |
596 | return generate_msg(st,LABEL_MSG4,"site:MSG4"); | |
597 | } | |
598 | ||
599 | static bool_t process_msg4(struct site *st, struct buffer_if *msg4, | |
a15faeb2 | 600 | const struct comm_addr *src) |
2fe58dfd SE |
601 | { |
602 | struct msg m; | |
3b83c932 | 603 | uint8_t *hash; |
2fe58dfd | 604 | void *hst; |
fe5e9cc4 | 605 | cstring_t err; |
2fe58dfd SE |
606 | |
607 | if (!unpick_msg(st,LABEL_MSG4,msg4,&m)) return False; | |
ff05a229 SE |
608 | if (!check_msg(st,LABEL_MSG4,&m,&err)) { |
609 | slog(st,LOG_SEC,"msg4: %s",err); | |
2fe58dfd SE |
610 | return False; |
611 | } | |
612 | ||
613 | /* Check signature and store g^x mod m */ | |
3b83c932 | 614 | hash=safe_malloc(st->hash->len, "process_msg4"); |
2fe58dfd SE |
615 | hst=st->hash->init(); |
616 | st->hash->update(hst,m.hashstart,m.hashlen); | |
617 | st->hash->final(hst,hash); | |
618 | /* Terminate signature with a '0' - cheating, but should be ok */ | |
619 | m.sig[m.siglen]=0; | |
620 | if (!st->pubkey->check(st->pubkey->st,hash,st->hash->len,m.sig)) { | |
59635212 | 621 | slog(st,LOG_SEC,"msg4 signature failed check!"); |
3b83c932 | 622 | free(hash); |
2fe58dfd SE |
623 | return False; |
624 | } | |
3b83c932 | 625 | free(hash); |
2fe58dfd SE |
626 | |
627 | /* Terminate their DH public key with a '0' */ | |
628 | m.pk[m.pklen]=0; | |
629 | /* Generate the shared key */ | |
630 | st->dh->makeshared(st->dh->st,st->dhsecret,st->dh->len,m.pk, | |
7c9ca4bd | 631 | st->sharedsecret,st->sharedsecretlen); |
2fe58dfd SE |
632 | /* Set up the transform */ |
633 | st->new_transform->setkey(st->new_transform->st,st->sharedsecret, | |
0118121a | 634 | st->sharedsecretlen,st->setup_priority); |
2fe58dfd SE |
635 | |
636 | return True; | |
637 | } | |
638 | ||
2fe58dfd SE |
639 | struct msg0 { |
640 | uint32_t dest; | |
641 | uint32_t source; | |
642 | uint32_t type; | |
643 | }; | |
644 | ||
645 | static bool_t unpick_msg0(struct site *st, struct buffer_if *msg0, | |
646 | struct msg0 *m) | |
647 | { | |
648 | CHECK_AVAIL(msg0,4); | |
59635212 | 649 | m->dest=buf_unprepend_uint32(msg0); |
2fe58dfd | 650 | CHECK_AVAIL(msg0,4); |
59635212 | 651 | m->source=buf_unprepend_uint32(msg0); |
2fe58dfd | 652 | CHECK_AVAIL(msg0,4); |
59635212 | 653 | m->type=buf_unprepend_uint32(msg0); |
2fe58dfd SE |
654 | return True; |
655 | /* Leaves transformed part of buffer untouched */ | |
656 | } | |
657 | ||
ff05a229 SE |
658 | static bool_t generate_msg5(struct site *st) |
659 | { | |
fe5e9cc4 | 660 | cstring_t transform_err; |
ff05a229 SE |
661 | |
662 | BUF_ALLOC(&st->buffer,"site:MSG5"); | |
663 | /* We are going to add four words to the message */ | |
664 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*4)); | |
665 | /* Give the netlink code an opportunity to put its own stuff in the | |
666 | message (configuration information, etc.) */ | |
ff05a229 SE |
667 | buf_prepend_uint32(&st->buffer,LABEL_MSG5); |
668 | st->new_transform->forwards(st->new_transform->st,&st->buffer, | |
669 | &transform_err); | |
670 | buf_prepend_uint32(&st->buffer,LABEL_MSG5); | |
58650a70 | 671 | buf_prepend_uint32(&st->buffer,st->index); |
ff05a229 SE |
672 | buf_prepend_uint32(&st->buffer,st->setup_session_id); |
673 | ||
674 | st->retries=st->setup_retries; | |
675 | return True; | |
676 | } | |
677 | ||
2fe58dfd | 678 | static bool_t process_msg5(struct site *st, struct buffer_if *msg5, |
c90cc2a7 IJ |
679 | const struct comm_addr *src, |
680 | struct transform_inst_if *transform) | |
2fe58dfd SE |
681 | { |
682 | struct msg0 m; | |
fe5e9cc4 | 683 | cstring_t transform_err; |
2fe58dfd SE |
684 | |
685 | if (!unpick_msg0(st,msg5,&m)) return False; | |
686 | ||
c90cc2a7 | 687 | if (transform->reverse(transform->st,msg5,&transform_err)) { |
2fe58dfd | 688 | /* There's a problem */ |
59635212 | 689 | slog(st,LOG_SEC,"process_msg5: transform: %s",transform_err); |
2fe58dfd SE |
690 | return False; |
691 | } | |
692 | /* Buffer should now contain untransformed PING packet data */ | |
693 | CHECK_AVAIL(msg5,4); | |
59635212 | 694 | if (buf_unprepend_uint32(msg5)!=LABEL_MSG5) { |
ff05a229 | 695 | slog(st,LOG_SEC,"MSG5/PING packet contained wrong label"); |
2fe58dfd SE |
696 | return False; |
697 | } | |
ff7cdc9e IJ |
698 | /* Older versions of secnet used to write some config data here |
699 | * which we ignore. So we don't CHECK_EMPTY */ | |
2fe58dfd SE |
700 | return True; |
701 | } | |
702 | ||
c90cc2a7 IJ |
703 | static void create_msg6(struct site *st, struct transform_inst_if *transform, |
704 | uint32_t session_id) | |
2fe58dfd | 705 | { |
fe5e9cc4 | 706 | cstring_t transform_err; |
2fe58dfd SE |
707 | |
708 | BUF_ALLOC(&st->buffer,"site:MSG6"); | |
ff05a229 SE |
709 | /* We are going to add four words to the message */ |
710 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*4)); | |
794f2398 SE |
711 | /* Give the netlink code an opportunity to put its own stuff in the |
712 | message (configuration information, etc.) */ | |
ff05a229 | 713 | buf_prepend_uint32(&st->buffer,LABEL_MSG6); |
c90cc2a7 | 714 | transform->forwards(transform->st,&st->buffer,&transform_err); |
59635212 | 715 | buf_prepend_uint32(&st->buffer,LABEL_MSG6); |
58650a70 | 716 | buf_prepend_uint32(&st->buffer,st->index); |
c90cc2a7 IJ |
717 | buf_prepend_uint32(&st->buffer,session_id); |
718 | } | |
2fe58dfd | 719 | |
c90cc2a7 IJ |
720 | static bool_t generate_msg6(struct site *st) |
721 | { | |
722 | create_msg6(st,st->new_transform,st->setup_session_id); | |
ff05a229 | 723 | st->retries=1; /* Peer will retransmit MSG5 if this packet gets lost */ |
2fe58dfd SE |
724 | return True; |
725 | } | |
726 | ||
727 | static bool_t process_msg6(struct site *st, struct buffer_if *msg6, | |
a15faeb2 | 728 | const struct comm_addr *src) |
2fe58dfd SE |
729 | { |
730 | struct msg0 m; | |
fe5e9cc4 | 731 | cstring_t transform_err; |
2fe58dfd SE |
732 | |
733 | if (!unpick_msg0(st,msg6,&m)) return False; | |
734 | ||
735 | if (st->new_transform->reverse(st->new_transform->st, | |
736 | msg6,&transform_err)) { | |
737 | /* There's a problem */ | |
59635212 | 738 | slog(st,LOG_SEC,"process_msg6: transform: %s",transform_err); |
2fe58dfd SE |
739 | return False; |
740 | } | |
741 | /* Buffer should now contain untransformed PING packet data */ | |
742 | CHECK_AVAIL(msg6,4); | |
59635212 SE |
743 | if (buf_unprepend_uint32(msg6)!=LABEL_MSG6) { |
744 | slog(st,LOG_SEC,"MSG6/PONG packet contained invalid data"); | |
2fe58dfd SE |
745 | return False; |
746 | } | |
ff7cdc9e IJ |
747 | /* Older versions of secnet used to write some config data here |
748 | * which we ignore. So we don't CHECK_EMPTY */ | |
2fe58dfd SE |
749 | return True; |
750 | } | |
751 | ||
48b97423 IJ |
752 | static bool_t decrypt_msg0(struct site *st, struct buffer_if *msg0, |
753 | const struct comm_addr *src) | |
2fe58dfd | 754 | { |
02b0959b | 755 | cstring_t transform_err, auxkey_err, newkey_err="n/a"; |
065e1922 IJ |
756 | struct msg0 m; |
757 | uint32_t problem; | |
2fe58dfd | 758 | |
2fe58dfd SE |
759 | if (!unpick_msg0(st,msg0,&m)) return False; |
760 | ||
05f39b4d IJ |
761 | /* Keep a copy so we can try decrypting it with multiple keys */ |
762 | buffer_copy(&st->scratch, msg0); | |
763 | ||
19e9a588 | 764 | problem = st->current.transform->reverse(st->current.transform->st, |
065e1922 | 765 | msg0,&transform_err); |
02b0959b | 766 | if (!problem) { |
bd98cd6b IJ |
767 | if (!st->auxiliary_is_new) |
768 | delete_one_key(st,&st->auxiliary_key, | |
769 | "peer has used new key","auxiliary key",LOG_SEC); | |
02b0959b IJ |
770 | return True; |
771 | } | |
48b97423 IJ |
772 | if (problem==2) |
773 | goto skew; | |
07e4774c | 774 | |
02b0959b IJ |
775 | buffer_copy(msg0, &st->scratch); |
776 | problem = st->auxiliary_key.transform->reverse | |
777 | (st->auxiliary_key.transform->st,msg0,&auxkey_err); | |
778 | if (problem==0) { | |
779 | slog(st,LOG_DROP,"processing packet which uses auxiliary key"); | |
bd98cd6b IJ |
780 | if (st->auxiliary_is_new) { |
781 | /* We previously timed out in state SENTMSG5 but it turns | |
782 | * out that our peer did in fact get our MSG5 and is | |
783 | * using the new key. So we should switch to it too. */ | |
784 | /* This is a bit like activate_new_key. */ | |
785 | struct data_key t; | |
786 | t=st->current; | |
787 | st->current=st->auxiliary_key; | |
788 | st->auxiliary_key=t; | |
789 | ||
790 | delete_one_key(st,&st->auxiliary_key,"peer has used new key", | |
791 | "previous key",LOG_SEC); | |
792 | st->auxiliary_is_new=0; | |
793 | st->renegotiate_key_time=st->auxiliary_renegotiate_key_time; | |
794 | } | |
02b0959b IJ |
795 | return True; |
796 | } | |
48b97423 IJ |
797 | if (problem==2) |
798 | goto skew; | |
02b0959b | 799 | |
05f39b4d IJ |
800 | if (st->state==SITE_SENTMSG5) { |
801 | buffer_copy(msg0, &st->scratch); | |
48b97423 IJ |
802 | problem = st->new_transform->reverse(st->new_transform->st, |
803 | msg0,&newkey_err); | |
804 | if (!problem) { | |
05f39b4d IJ |
805 | /* It looks like we didn't get the peer's MSG6 */ |
806 | /* This is like a cut-down enter_new_state(SITE_RUN) */ | |
807 | slog(st,LOG_STATE,"will enter state RUN (MSG0 with new key)"); | |
808 | BUF_FREE(&st->buffer); | |
809 | st->timeout=0; | |
810 | activate_new_key(st); | |
811 | return True; /* do process the data in this packet */ | |
812 | } | |
48b97423 IJ |
813 | if (problem==2) |
814 | goto skew; | |
05f39b4d IJ |
815 | } |
816 | ||
02b0959b IJ |
817 | slog(st,LOG_SEC,"transform: %s (aux: %s, new: %s)", |
818 | transform_err,auxkey_err,newkey_err); | |
065e1922 | 819 | initiate_key_setup(st,"incoming message would not decrypt"); |
48b97423 IJ |
820 | send_nak(src,m.dest,m.source,m.type,msg0,"message would not decrypt"); |
821 | return False; | |
822 | ||
823 | skew: | |
824 | slog(st,LOG_DROP,"transform: %s (merely skew)",transform_err); | |
065e1922 IJ |
825 | return False; |
826 | } | |
827 | ||
828 | static bool_t process_msg0(struct site *st, struct buffer_if *msg0, | |
829 | const struct comm_addr *src) | |
830 | { | |
831 | uint32_t type; | |
832 | ||
48b97423 | 833 | if (!decrypt_msg0(st,msg0,src)) |
065e1922 IJ |
834 | return False; |
835 | ||
2fe58dfd | 836 | CHECK_AVAIL(msg0,4); |
59635212 | 837 | type=buf_unprepend_uint32(msg0); |
2fe58dfd | 838 | switch(type) { |
794f2398 SE |
839 | case LABEL_MSG7: |
840 | /* We must forget about the current session. */ | |
1d388569 | 841 | delete_keys(st,"request from peer",LOG_SEC); |
794f2398 | 842 | return True; |
2fe58dfd SE |
843 | case LABEL_MSG9: |
844 | /* Deliver to netlink layer */ | |
469fd1d9 | 845 | st->netlink->deliver(st->netlink->st,msg0); |
446353cd | 846 | transport_data_msgok(st,src); |
837cf01e IJ |
847 | /* See whether we should start negotiating a new key */ |
848 | if (st->now > st->renegotiate_key_time) | |
849 | initiate_key_setup(st,"incoming packet in renegotiation window"); | |
2fe58dfd | 850 | return True; |
2fe58dfd | 851 | default: |
ff05a229 SE |
852 | slog(st,LOG_SEC,"incoming encrypted message of type %08x " |
853 | "(unknown)",type); | |
2fe58dfd SE |
854 | break; |
855 | } | |
856 | return False; | |
857 | } | |
858 | ||
859 | static void dump_packet(struct site *st, struct buffer_if *buf, | |
a15faeb2 | 860 | const struct comm_addr *addr, bool_t incoming) |
2fe58dfd | 861 | { |
59635212 SE |
862 | uint32_t dest=ntohl(*(uint32_t *)buf->start); |
863 | uint32_t source=ntohl(*(uint32_t *)(buf->start+4)); | |
864 | uint32_t msgtype=ntohl(*(uint32_t *)(buf->start+8)); | |
2fe58dfd SE |
865 | |
866 | if (st->log_events & LOG_DUMP) | |
040ee979 SE |
867 | slilog(st->log,M_DEBUG,"%s: %s: %08x<-%08x: %08x:", |
868 | st->tunname,incoming?"incoming":"outgoing", | |
869 | dest,source,msgtype); | |
2fe58dfd SE |
870 | } |
871 | ||
872 | static uint32_t site_status(void *st) | |
873 | { | |
874 | return 0; | |
875 | } | |
876 | ||
877 | static bool_t send_msg(struct site *st) | |
878 | { | |
879 | if (st->retries>0) { | |
446353cd | 880 | transport_xmit(st, &st->setup_peers, &st->buffer, True); |
e7f8ec2a | 881 | st->timeout=st->now+st->setup_retry_interval; |
2fe58dfd SE |
882 | st->retries--; |
883 | return True; | |
bd98cd6b IJ |
884 | } else if (st->state==SITE_SENTMSG5) { |
885 | slog(st,LOG_SETUP_TIMEOUT,"timed out sending MSG5, stashing new key"); | |
886 | /* We stash the key we have produced, in case it turns out that | |
887 | * our peer did see our MSG5 after all and starts using it. */ | |
888 | /* This is a bit like some of activate_new_key */ | |
889 | struct transform_inst_if *t; | |
890 | t=st->auxiliary_key.transform; | |
891 | st->auxiliary_key.transform=st->new_transform; | |
892 | st->new_transform=t; | |
893 | ||
894 | t->delkey(t->st); | |
895 | st->auxiliary_is_new=1; | |
896 | st->auxiliary_key.key_timeout=st->now+st->key_lifetime; | |
897 | st->auxiliary_renegotiate_key_time=st->now+st->key_renegotiate_time; | |
898 | st->auxiliary_key.remote_session_id=st->setup_session_id; | |
899 | ||
900 | enter_state_wait(st); | |
901 | return False; | |
2fe58dfd | 902 | } else { |
3454dce4 SE |
903 | slog(st,LOG_SETUP_TIMEOUT,"timed out sending key setup packet " |
904 | "(in state %s)",state_name(st->state)); | |
2fe58dfd SE |
905 | enter_state_wait(st); |
906 | return False; | |
907 | } | |
908 | } | |
909 | ||
910 | static void site_resolve_callback(void *sst, struct in_addr *address) | |
911 | { | |
912 | struct site *st=sst; | |
446353cd | 913 | struct comm_addr ca_buf, *ca_use; |
2fe58dfd SE |
914 | |
915 | if (st->state!=SITE_RESOLVE) { | |
916 | slog(st,LOG_UNEXPECTED,"site_resolve_callback called unexpectedly"); | |
917 | return; | |
918 | } | |
919 | if (address) { | |
446353cd | 920 | FILLZERO(ca_buf); |
59533c16 | 921 | ca_buf.comm=st->comms[0]; |
446353cd IJ |
922 | ca_buf.sin.sin_family=AF_INET; |
923 | ca_buf.sin.sin_port=htons(st->remoteport); | |
924 | ca_buf.sin.sin_addr=*address; | |
925 | ca_use=&ca_buf; | |
2fe58dfd | 926 | } else { |
2fe58dfd | 927 | slog(st,LOG_ERROR,"resolution of %s failed",st->address); |
446353cd IJ |
928 | ca_use=0; |
929 | } | |
930 | if (transport_compute_setupinit_peers(st,ca_use)) { | |
931 | enter_new_state(st,SITE_SENTMSG1); | |
932 | } else { | |
933 | /* Can't figure out who to try to to talk to */ | |
934 | slog(st,LOG_SETUP_INIT,"key exchange failed: cannot find peer address"); | |
2fe58dfd SE |
935 | enter_state_run(st); |
936 | } | |
937 | } | |
938 | ||
fe5e9cc4 | 939 | static bool_t initiate_key_setup(struct site *st, cstring_t reason) |
9d3a4132 SE |
940 | { |
941 | if (st->state!=SITE_RUN) return False; | |
794f2398 | 942 | slog(st,LOG_SETUP_INIT,"initiating key exchange (%s)",reason); |
9d3a4132 | 943 | if (st->address) { |
794f2398 | 944 | slog(st,LOG_SETUP_INIT,"resolving peer address"); |
9d3a4132 | 945 | return enter_state_resolve(st); |
446353cd | 946 | } else if (transport_compute_setupinit_peers(st,0)) { |
ff05a229 | 947 | return enter_new_state(st,SITE_SENTMSG1); |
9d3a4132 | 948 | } |
ff05a229 | 949 | slog(st,LOG_SETUP_INIT,"key exchange failed: no address for peer"); |
9d3a4132 SE |
950 | return False; |
951 | } | |
952 | ||
2fe58dfd SE |
953 | static void activate_new_key(struct site *st) |
954 | { | |
955 | struct transform_inst_if *t; | |
956 | ||
02b0959b IJ |
957 | /* We have three transform instances, which we swap between old, |
958 | active and setup */ | |
959 | t=st->auxiliary_key.transform; | |
960 | st->auxiliary_key.transform=st->current.transform; | |
19e9a588 | 961 | st->current.transform=st->new_transform; |
2fe58dfd SE |
962 | st->new_transform=t; |
963 | ||
964 | t->delkey(t->st); | |
2fe58dfd | 965 | st->timeout=0; |
bd98cd6b | 966 | st->auxiliary_is_new=0; |
02b0959b | 967 | st->auxiliary_key.key_timeout=st->current.key_timeout; |
19e9a588 | 968 | st->current.key_timeout=st->now+st->key_lifetime; |
ff05a229 | 969 | st->renegotiate_key_time=st->now+st->key_renegotiate_time; |
446353cd | 970 | transport_peers_copy(st,&st->peers,&st->setup_peers); |
19e9a588 | 971 | st->current.remote_session_id=st->setup_session_id; |
2fe58dfd SE |
972 | |
973 | slog(st,LOG_ACTIVATE_KEY,"new key activated"); | |
9d3a4132 | 974 | enter_state_run(st); |
2fe58dfd SE |
975 | } |
976 | ||
1d388569 IJ |
977 | static void delete_one_key(struct site *st, struct data_key *key, |
978 | cstring_t reason, cstring_t which, uint32_t loglevel) | |
979 | { | |
980 | if (!key->transform->valid(key->transform->st)) return; | |
981 | if (reason) slog(st,loglevel,"%s deleted (%s)",which,reason); | |
982 | key->transform->delkey(key->transform->st); | |
983 | key->key_timeout=0; | |
984 | } | |
985 | ||
986 | static void delete_keys(struct site *st, cstring_t reason, uint32_t loglevel) | |
794f2398 | 987 | { |
3d8d8f4e | 988 | if (current_valid(st)) { |
794f2398 SE |
989 | slog(st,loglevel,"session closed (%s)",reason); |
990 | ||
1d388569 | 991 | delete_one_key(st,&st->current,0,0,0); |
794f2398 SE |
992 | set_link_quality(st); |
993 | } | |
02b0959b | 994 | delete_one_key(st,&st->auxiliary_key,0,0,0); |
794f2398 SE |
995 | } |
996 | ||
2fe58dfd SE |
997 | static void state_assert(struct site *st, bool_t ok) |
998 | { | |
4f5e39ec | 999 | if (!ok) fatal("site:state_assert"); |
2fe58dfd SE |
1000 | } |
1001 | ||
1002 | static void enter_state_stop(struct site *st) | |
1003 | { | |
1004 | st->state=SITE_STOP; | |
1005 | st->timeout=0; | |
1d388569 | 1006 | delete_keys(st,"entering state STOP",LOG_TIMEOUT_KEY); |
2fe58dfd SE |
1007 | st->new_transform->delkey(st->new_transform->st); |
1008 | } | |
1009 | ||
9d3a4132 SE |
1010 | static void set_link_quality(struct site *st) |
1011 | { | |
1012 | uint32_t quality; | |
3d8d8f4e | 1013 | if (current_valid(st)) |
9d3a4132 SE |
1014 | quality=LINK_QUALITY_UP; |
1015 | else if (st->state==SITE_WAIT || st->state==SITE_STOP) | |
1016 | quality=LINK_QUALITY_DOWN; | |
1017 | else if (st->address) | |
1018 | quality=LINK_QUALITY_DOWN_CURRENT_ADDRESS; | |
446353cd | 1019 | else if (transport_peers_valid(&st->peers)) |
9d3a4132 SE |
1020 | quality=LINK_QUALITY_DOWN_STALE_ADDRESS; |
1021 | else | |
1022 | quality=LINK_QUALITY_DOWN; | |
1023 | ||
469fd1d9 | 1024 | st->netlink->set_quality(st->netlink->st,quality); |
9d3a4132 SE |
1025 | } |
1026 | ||
2fe58dfd SE |
1027 | static void enter_state_run(struct site *st) |
1028 | { | |
1029 | slog(st,LOG_STATE,"entering state RUN"); | |
1030 | st->state=SITE_RUN; | |
1031 | st->timeout=0; | |
9d3a4132 | 1032 | |
ff05a229 | 1033 | st->setup_session_id=0; |
446353cd | 1034 | transport_peers_clear(st,&st->setup_peers); |
ff05a229 SE |
1035 | memset(st->localN,0,NONCELEN); |
1036 | memset(st->remoteN,0,NONCELEN); | |
1037 | st->new_transform->delkey(st->new_transform->st); | |
1038 | memset(st->dhsecret,0,st->dh->len); | |
7c9ca4bd | 1039 | memset(st->sharedsecret,0,st->sharedsecretlen); |
9d3a4132 | 1040 | set_link_quality(st); |
2fe58dfd SE |
1041 | } |
1042 | ||
1043 | static bool_t enter_state_resolve(struct site *st) | |
1044 | { | |
1045 | state_assert(st,st->state==SITE_RUN); | |
1046 | slog(st,LOG_STATE,"entering state RESOLVE"); | |
1047 | st->state=SITE_RESOLVE; | |
1048 | st->resolver->request(st->resolver->st,st->address, | |
1049 | site_resolve_callback,st); | |
1050 | return True; | |
1051 | } | |
1052 | ||
ff05a229 | 1053 | static bool_t enter_new_state(struct site *st, uint32_t next) |
2fe58dfd | 1054 | { |
ff05a229 | 1055 | bool_t (*gen)(struct site *st); |
3b83c932 SE |
1056 | int r; |
1057 | ||
ff05a229 SE |
1058 | slog(st,LOG_STATE,"entering state %s",state_name(next)); |
1059 | switch(next) { | |
1060 | case SITE_SENTMSG1: | |
1061 | state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE); | |
1062 | gen=generate_msg1; | |
1063 | break; | |
1064 | case SITE_SENTMSG2: | |
1065 | state_assert(st,st->state==SITE_RUN || st->state==SITE_RESOLVE || | |
1066 | st->state==SITE_SENTMSG1 || st->state==SITE_WAIT); | |
1067 | gen=generate_msg2; | |
1068 | break; | |
1069 | case SITE_SENTMSG3: | |
1070 | state_assert(st,st->state==SITE_SENTMSG1); | |
1071 | BUF_FREE(&st->buffer); | |
1072 | gen=generate_msg3; | |
1073 | break; | |
1074 | case SITE_SENTMSG4: | |
1075 | state_assert(st,st->state==SITE_SENTMSG2); | |
1076 | BUF_FREE(&st->buffer); | |
1077 | gen=generate_msg4; | |
1078 | break; | |
1079 | case SITE_SENTMSG5: | |
1080 | state_assert(st,st->state==SITE_SENTMSG3); | |
1081 | BUF_FREE(&st->buffer); | |
1082 | gen=generate_msg5; | |
1083 | break; | |
1084 | case SITE_RUN: | |
1085 | state_assert(st,st->state==SITE_SENTMSG4); | |
1086 | BUF_FREE(&st->buffer); | |
1087 | gen=generate_msg6; | |
1088 | break; | |
1089 | default: | |
1090 | gen=NULL; | |
4f5e39ec | 1091 | fatal("enter_new_state(%s): invalid new state",state_name(next)); |
ff05a229 | 1092 | break; |
2fe58dfd | 1093 | } |
2fe58dfd | 1094 | |
3b83c932 SE |
1095 | if (hacky_par_start_failnow()) return False; |
1096 | ||
1097 | r= gen(st) && send_msg(st); | |
1098 | ||
1099 | hacky_par_end(&r, | |
e7f8ec2a | 1100 | st->setup_retries, st->setup_retry_interval, |
3b83c932 SE |
1101 | send_msg, st); |
1102 | ||
1103 | if (r) { | |
ff05a229 SE |
1104 | st->state=next; |
1105 | if (next==SITE_RUN) { | |
1106 | BUF_FREE(&st->buffer); /* Never reused */ | |
1107 | st->timeout=0; /* Never retransmit */ | |
1108 | activate_new_key(st); | |
1109 | } | |
2fe58dfd SE |
1110 | return True; |
1111 | } | |
ff05a229 SE |
1112 | slog(st,LOG_ERROR,"error entering state %s",state_name(next)); |
1113 | st->buffer.free=False; /* Unconditionally use the buffer; it may be | |
1114 | in either state, and enter_state_wait() will | |
1115 | do a BUF_FREE() */ | |
2fe58dfd SE |
1116 | enter_state_wait(st); |
1117 | return False; | |
1118 | } | |
1119 | ||
ff05a229 | 1120 | /* msg7 tells our peer that we're about to forget our key */ |
fe5e9cc4 | 1121 | static bool_t send_msg7(struct site *st, cstring_t reason) |
794f2398 | 1122 | { |
fe5e9cc4 | 1123 | cstring_t transform_err; |
794f2398 | 1124 | |
3d8d8f4e | 1125 | if (current_valid(st) && st->buffer.free |
446353cd | 1126 | && transport_peers_valid(&st->peers)) { |
794f2398 SE |
1127 | BUF_ALLOC(&st->buffer,"site:MSG7"); |
1128 | buffer_init(&st->buffer,st->transform->max_start_pad+(4*3)); | |
1129 | buf_append_uint32(&st->buffer,LABEL_MSG7); | |
1130 | buf_append_string(&st->buffer,reason); | |
19e9a588 | 1131 | st->current.transform->forwards(st->current.transform->st, |
794f2398 SE |
1132 | &st->buffer, &transform_err); |
1133 | buf_prepend_uint32(&st->buffer,LABEL_MSG0); | |
58650a70 | 1134 | buf_prepend_uint32(&st->buffer,st->index); |
19e9a588 | 1135 | buf_prepend_uint32(&st->buffer,st->current.remote_session_id); |
446353cd | 1136 | transport_xmit(st,&st->peers,&st->buffer,True); |
794f2398 SE |
1137 | BUF_FREE(&st->buffer); |
1138 | return True; | |
1139 | } | |
1140 | return False; | |
1141 | } | |
1142 | ||
2fe58dfd SE |
1143 | /* We go into this state if our peer becomes uncommunicative. Similar to |
1144 | the "stop" state, we forget all session keys for a while, before | |
1145 | re-entering the "run" state. */ | |
1146 | static void enter_state_wait(struct site *st) | |
1147 | { | |
1148 | slog(st,LOG_STATE,"entering state WAIT"); | |
1149 | st->timeout=st->now+st->wait_timeout; | |
1150 | st->state=SITE_WAIT; | |
9d3a4132 | 1151 | set_link_quality(st); |
2fe58dfd SE |
1152 | BUF_FREE(&st->buffer); /* will have had an outgoing packet in it */ |
1153 | /* XXX Erase keys etc. */ | |
1154 | } | |
1155 | ||
16f73fa6 | 1156 | static inline void site_settimeout(uint64_t timeout, int *timeout_io) |
fe5e9cc4 SE |
1157 | { |
1158 | if (timeout) { | |
0009e60a IJ |
1159 | int64_t offset=timeout-*now; |
1160 | if (offset<0) offset=0; | |
fe5e9cc4 SE |
1161 | if (offset>INT_MAX) offset=INT_MAX; |
1162 | if (*timeout_io<0 || offset<*timeout_io) | |
1163 | *timeout_io=offset; | |
1164 | } | |
1165 | } | |
1166 | ||
2fe58dfd | 1167 | static int site_beforepoll(void *sst, struct pollfd *fds, int *nfds_io, |
90a39563 | 1168 | int *timeout_io) |
2fe58dfd SE |
1169 | { |
1170 | struct site *st=sst; | |
1171 | ||
1172 | *nfds_io=0; /* We don't use any file descriptors */ | |
1173 | st->now=*now; | |
1174 | ||
1175 | /* Work out when our next timeout is. The earlier of 'timeout' or | |
19e9a588 | 1176 | 'current.key_timeout'. A stored value of '0' indicates no timeout |
2fe58dfd | 1177 | active. */ |
16f73fa6 | 1178 | site_settimeout(st->timeout, timeout_io); |
19e9a588 | 1179 | site_settimeout(st->current.key_timeout, timeout_io); |
02b0959b | 1180 | site_settimeout(st->auxiliary_key.key_timeout, timeout_io); |
2fe58dfd SE |
1181 | |
1182 | return 0; /* success */ | |
1183 | } | |
1184 | ||
1d388569 IJ |
1185 | static void check_expiry(struct site *st, struct data_key *key, |
1186 | const char *which) | |
1187 | { | |
1188 | if (key->key_timeout && *now>key->key_timeout) { | |
1189 | delete_one_key(st,key,"maximum life exceeded",which,LOG_TIMEOUT_KEY); | |
1190 | } | |
1191 | } | |
1192 | ||
2fe58dfd | 1193 | /* NB site_afterpoll will be called before site_beforepoll is ever called */ |
90a39563 | 1194 | static void site_afterpoll(void *sst, struct pollfd *fds, int nfds) |
2fe58dfd SE |
1195 | { |
1196 | struct site *st=sst; | |
1197 | ||
1198 | st->now=*now; | |
1199 | if (st->timeout && *now>st->timeout) { | |
2fe58dfd | 1200 | st->timeout=0; |
3b83c932 SE |
1201 | if (st->state>=SITE_SENTMSG1 && st->state<=SITE_SENTMSG5) { |
1202 | if (!hacky_par_start_failnow()) | |
1203 | send_msg(st); | |
1204 | } else if (st->state==SITE_WAIT) { | |
2fe58dfd SE |
1205 | enter_state_run(st); |
1206 | } else { | |
1207 | slog(st,LOG_ERROR,"site_afterpoll: unexpected timeout, state=%d", | |
1208 | st->state); | |
1209 | } | |
1210 | } | |
1d388569 | 1211 | check_expiry(st,&st->current,"current key"); |
02b0959b | 1212 | check_expiry(st,&st->auxiliary_key,"auxiliary key"); |
2fe58dfd SE |
1213 | } |
1214 | ||
1215 | /* This function is called by the netlink device to deliver packets | |
1216 | intended for the remote network. The packet is in "raw" wire | |
1217 | format, but is guaranteed to be word-aligned. */ | |
469fd1d9 | 1218 | static void site_outgoing(void *sst, struct buffer_if *buf) |
2fe58dfd SE |
1219 | { |
1220 | struct site *st=sst; | |
fe5e9cc4 | 1221 | cstring_t transform_err; |
2fe58dfd SE |
1222 | |
1223 | if (st->state==SITE_STOP) { | |
1224 | BUF_FREE(buf); | |
1225 | return; | |
1226 | } | |
1227 | ||
1228 | /* In all other states we consider delivering the packet if we have | |
1229 | a valid key and a valid address to send it to. */ | |
3d8d8f4e | 1230 | if (current_valid(st) && transport_peers_valid(&st->peers)) { |
2fe58dfd | 1231 | /* Transform it and send it */ |
70dc107b SE |
1232 | if (buf->size>0) { |
1233 | buf_prepend_uint32(buf,LABEL_MSG9); | |
19e9a588 | 1234 | st->current.transform->forwards(st->current.transform->st, |
70dc107b SE |
1235 | buf, &transform_err); |
1236 | buf_prepend_uint32(buf,LABEL_MSG0); | |
58650a70 | 1237 | buf_prepend_uint32(buf,st->index); |
19e9a588 | 1238 | buf_prepend_uint32(buf,st->current.remote_session_id); |
446353cd | 1239 | transport_xmit(st,&st->peers,buf,False); |
70dc107b | 1240 | } |
2fe58dfd SE |
1241 | BUF_FREE(buf); |
1242 | return; | |
1243 | } | |
1244 | ||
70dc107b | 1245 | slog(st,LOG_DROP,"discarding outgoing packet of size %d",buf->size); |
2fe58dfd | 1246 | BUF_FREE(buf); |
794f2398 | 1247 | initiate_key_setup(st,"outgoing packet"); |
2fe58dfd SE |
1248 | } |
1249 | ||
7e29719e IJ |
1250 | static bool_t named_for_us(struct site *st, const struct buffer_if *buf_in, |
1251 | uint32_t type, struct msg *m) | |
1252 | /* For packets which are identified by the local and remote names. | |
1253 | * If it has our name and our peer's name in it it's for us. */ | |
1254 | { | |
1255 | struct buffer_if buf[1]; | |
1256 | buffer_readonly_clone(buf,buf_in); | |
1257 | return unpick_msg(st,type,buf,m) | |
1258 | && name_matches(&m->remote,st->remotename) | |
1259 | && name_matches(&m->local,st->localname); | |
1260 | } | |
1261 | ||
2fe58dfd SE |
1262 | /* This function is called by the communication device to deliver |
1263 | packets from our peers. */ | |
1264 | static bool_t site_incoming(void *sst, struct buffer_if *buf, | |
a15faeb2 | 1265 | const struct comm_addr *source) |
2fe58dfd SE |
1266 | { |
1267 | struct site *st=sst; | |
20138876 IJ |
1268 | |
1269 | if (buf->size < 12) return False; | |
1270 | ||
7e29719e | 1271 | uint32_t msgtype=ntohl(get_uint32(buf->start+8)); |
59635212 | 1272 | uint32_t dest=ntohl(*(uint32_t *)buf->start); |
7e29719e IJ |
1273 | struct msg named_msg; |
1274 | ||
1275 | if (msgtype==LABEL_MSG1) { | |
1276 | if (!named_for_us(st,buf,msgtype,&named_msg)) | |
1277 | return False; | |
1278 | /* It's a MSG1 addressed to us. Decide what to do about it. */ | |
1279 | dump_packet(st,buf,source,True); | |
1280 | if (st->state==SITE_RUN || st->state==SITE_RESOLVE || | |
1281 | st->state==SITE_WAIT) { | |
1282 | /* We should definitely process it */ | |
1283 | if (process_msg1(st,buf,source,&named_msg)) { | |
1284 | slog(st,LOG_SETUP_INIT,"key setup initiated by peer"); | |
1285 | enter_new_state(st,SITE_SENTMSG2); | |
1286 | } else { | |
1287 | slog(st,LOG_ERROR,"failed to process incoming msg1"); | |
1288 | } | |
1289 | BUF_FREE(buf); | |
1290 | return True; | |
1291 | } else if (st->state==SITE_SENTMSG1) { | |
1292 | /* We've just sent a message 1! They may have crossed on | |
1293 | the wire. If we have priority then we ignore the | |
1294 | incoming one, otherwise we process it as usual. */ | |
1295 | if (st->setup_priority) { | |
1296 | BUF_FREE(buf); | |
1297 | slog(st,LOG_DUMP,"crossed msg1s; we are higher " | |
1298 | "priority => ignore incoming msg1"); | |
1299 | return True; | |
1300 | } else { | |
1301 | slog(st,LOG_DUMP,"crossed msg1s; we are lower " | |
1302 | "priority => use incoming msg1"); | |
1303 | if (process_msg1(st,buf,source,&named_msg)) { | |
1304 | BUF_FREE(&st->buffer); /* Free our old message 1 */ | |
ff05a229 | 1305 | enter_new_state(st,SITE_SENTMSG2); |
2fe58dfd | 1306 | } else { |
7e29719e IJ |
1307 | slog(st,LOG_ERROR,"failed to process an incoming " |
1308 | "crossed msg1 (we have low priority)"); | |
2fe58dfd SE |
1309 | } |
1310 | BUF_FREE(buf); | |
1311 | return True; | |
2fe58dfd | 1312 | } |
2fe58dfd | 1313 | } |
7e29719e IJ |
1314 | /* The message 1 was received at an unexpected stage of the |
1315 | key setup. XXX POLICY - what do we do? */ | |
1316 | slog(st,LOG_UNEXPECTED,"unexpected incoming message 1"); | |
1317 | BUF_FREE(buf); | |
1318 | return True; | |
2fe58dfd | 1319 | } |
58650a70 | 1320 | if (dest==st->index) { |
2fe58dfd SE |
1321 | /* Explicitly addressed to us */ |
1322 | if (msgtype!=LABEL_MSG0) dump_packet(st,buf,source,True); | |
1323 | switch (msgtype) { | |
136740e6 | 1324 | case LABEL_NAK: |
794f2398 SE |
1325 | /* If the source is our current peer then initiate a key setup, |
1326 | because our peer's forgotten the key */ | |
19e9a588 | 1327 | if (get_uint32(buf->start+4)==st->current.remote_session_id) { |
794f2398 SE |
1328 | initiate_key_setup(st,"received a NAK"); |
1329 | } else { | |
1330 | slog(st,LOG_SEC,"bad incoming NAK"); | |
1331 | } | |
1332 | break; | |
2fe58dfd SE |
1333 | case LABEL_MSG0: |
1334 | process_msg0(st,buf,source); | |
1335 | break; | |
1336 | case LABEL_MSG1: | |
1337 | /* Setup packet: should not have been explicitly addressed | |
1338 | to us */ | |
59635212 | 1339 | slog(st,LOG_SEC,"incoming explicitly addressed msg1"); |
2fe58dfd SE |
1340 | break; |
1341 | case LABEL_MSG2: | |
1342 | /* Setup packet: expected only in state SENTMSG1 */ | |
1343 | if (st->state!=SITE_SENTMSG1) { | |
1344 | slog(st,LOG_UNEXPECTED,"unexpected MSG2"); | |
446353cd IJ |
1345 | } else if (process_msg2(st,buf,source)) { |
1346 | transport_setup_msgok(st,source); | |
ff05a229 | 1347 | enter_new_state(st,SITE_SENTMSG3); |
446353cd | 1348 | } else { |
59635212 | 1349 | slog(st,LOG_SEC,"invalid MSG2"); |
2fe58dfd SE |
1350 | } |
1351 | break; | |
1352 | case LABEL_MSG3: | |
1353 | /* Setup packet: expected only in state SENTMSG2 */ | |
1354 | if (st->state!=SITE_SENTMSG2) { | |
1355 | slog(st,LOG_UNEXPECTED,"unexpected MSG3"); | |
446353cd IJ |
1356 | } else if (process_msg3(st,buf,source)) { |
1357 | transport_setup_msgok(st,source); | |
ff05a229 | 1358 | enter_new_state(st,SITE_SENTMSG4); |
446353cd | 1359 | } else { |
59635212 | 1360 | slog(st,LOG_SEC,"invalid MSG3"); |
2fe58dfd SE |
1361 | } |
1362 | break; | |
1363 | case LABEL_MSG4: | |
1364 | /* Setup packet: expected only in state SENTMSG3 */ | |
1365 | if (st->state!=SITE_SENTMSG3) { | |
1366 | slog(st,LOG_UNEXPECTED,"unexpected MSG4"); | |
446353cd IJ |
1367 | } else if (process_msg4(st,buf,source)) { |
1368 | transport_setup_msgok(st,source); | |
ff05a229 | 1369 | enter_new_state(st,SITE_SENTMSG5); |
446353cd | 1370 | } else { |
59635212 | 1371 | slog(st,LOG_SEC,"invalid MSG4"); |
2fe58dfd SE |
1372 | } |
1373 | break; | |
1374 | case LABEL_MSG5: | |
4efd681a SE |
1375 | /* Setup packet: expected only in state SENTMSG4 */ |
1376 | /* (may turn up in state RUN if our return MSG6 was lost | |
1377 | and the new key has already been activated. In that | |
05f39b4d IJ |
1378 | case we discard it. The peer will realise that we |
1379 | are using the new key when they see our data packets. | |
1380 | Until then the peer's data packets to us get discarded. */ | |
c90cc2a7 IJ |
1381 | if (st->state==SITE_SENTMSG4) { |
1382 | if (process_msg5(st,buf,source,st->new_transform)) { | |
1383 | transport_setup_msgok(st,source); | |
1384 | enter_new_state(st,SITE_RUN); | |
1385 | } else { | |
1386 | slog(st,LOG_SEC,"invalid MSG5"); | |
1387 | } | |
1388 | } else if (st->state==SITE_RUN) { | |
19e9a588 | 1389 | if (process_msg5(st,buf,source,st->current.transform)) { |
c90cc2a7 IJ |
1390 | slog(st,LOG_DROP,"got MSG5, retransmitting MSG6"); |
1391 | transport_setup_msgok(st,source); | |
19e9a588 IJ |
1392 | create_msg6(st,st->current.transform, |
1393 | st->current.remote_session_id); | |
c90cc2a7 IJ |
1394 | transport_xmit(st,&st->peers,&st->buffer,True); |
1395 | BUF_FREE(&st->buffer); | |
1396 | } else { | |
1397 | slog(st,LOG_SEC,"invalid MSG5 (in state RUN)"); | |
1398 | } | |
2fe58dfd | 1399 | } else { |
c90cc2a7 | 1400 | slog(st,LOG_UNEXPECTED,"unexpected MSG5"); |
2fe58dfd SE |
1401 | } |
1402 | break; | |
1403 | case LABEL_MSG6: | |
1404 | /* Setup packet: expected only in state SENTMSG5 */ | |
1405 | if (st->state!=SITE_SENTMSG5) { | |
1406 | slog(st,LOG_UNEXPECTED,"unexpected MSG6"); | |
1407 | } else if (process_msg6(st,buf,source)) { | |
1408 | BUF_FREE(&st->buffer); /* Free message 5 */ | |
446353cd | 1409 | transport_setup_msgok(st,source); |
2fe58dfd SE |
1410 | activate_new_key(st); |
1411 | } else { | |
59635212 | 1412 | slog(st,LOG_SEC,"invalid MSG6"); |
2fe58dfd SE |
1413 | } |
1414 | break; | |
2fe58dfd | 1415 | default: |
59635212 | 1416 | slog(st,LOG_SEC,"received message of unknown type 0x%08x", |
2fe58dfd SE |
1417 | msgtype); |
1418 | break; | |
1419 | } | |
1420 | BUF_FREE(buf); | |
1421 | return True; | |
1422 | } | |
1423 | ||
1424 | return False; | |
1425 | } | |
1426 | ||
1427 | static void site_control(void *vst, bool_t run) | |
1428 | { | |
1429 | struct site *st=vst; | |
1430 | if (run) enter_state_run(st); | |
1431 | else enter_state_stop(st); | |
1432 | } | |
1433 | ||
794f2398 SE |
1434 | static void site_phase_hook(void *sst, uint32_t newphase) |
1435 | { | |
1436 | struct site *st=sst; | |
1437 | ||
1438 | /* The program is shutting down; tell our peer */ | |
1439 | send_msg7(st,"shutting down"); | |
1440 | } | |
1441 | ||
2fe58dfd SE |
1442 | static list_t *site_apply(closure_t *self, struct cloc loc, dict_t *context, |
1443 | list_t *args) | |
1444 | { | |
58650a70 | 1445 | static uint32_t index_sequence; |
2fe58dfd SE |
1446 | struct site *st; |
1447 | item_t *item; | |
1448 | dict_t *dict; | |
59533c16 | 1449 | int i; |
2fe58dfd SE |
1450 | |
1451 | st=safe_malloc(sizeof(*st),"site_apply"); | |
1452 | ||
1453 | st->cl.description="site"; | |
1454 | st->cl.type=CL_SITE; | |
1455 | st->cl.apply=NULL; | |
1456 | st->cl.interface=&st->ops; | |
1457 | st->ops.st=st; | |
1458 | st->ops.control=site_control; | |
1459 | st->ops.status=site_status; | |
1460 | ||
1461 | /* First parameter must be a dict */ | |
1462 | item=list_elem(args,0); | |
1463 | if (!item || item->type!=t_dict) | |
1464 | cfgfatal(loc,"site","parameter must be a dictionary\n"); | |
1465 | ||
1466 | dict=item->data.dict; | |
558fa3fb SE |
1467 | st->localname=dict_read_string(dict, "local-name", True, "site", loc); |
1468 | st->remotename=dict_read_string(dict, "name", True, "site", loc); | |
dba19f84 IJ |
1469 | |
1470 | st->peer_mobile=dict_read_bool(dict,"mobile",False,"site",loc,False); | |
1471 | bool_t local_mobile= | |
1472 | dict_read_bool(dict,"local-mobile",False,"site",loc,False); | |
1473 | ||
558fa3fb SE |
1474 | /* Sanity check (which also allows the 'sites' file to include |
1475 | site() closures for all sites including our own): refuse to | |
1476 | talk to ourselves */ | |
1477 | if (strcmp(st->localname,st->remotename)==0) { | |
b2a56f7c | 1478 | Message(M_DEBUG,"site %s: local-name==name -> ignoring this site\n", |
baa06aeb | 1479 | st->localname); |
dba19f84 IJ |
1480 | if (st->peer_mobile != local_mobile) |
1481 | cfgfatal(loc,"site","site %s's peer-mobile=%d" | |
1482 | " but our local-mobile=%d\n", | |
1483 | st->localname, st->peer_mobile, local_mobile); | |
1484 | free(st); | |
1485 | return NULL; | |
1486 | } | |
1487 | if (st->peer_mobile && local_mobile) { | |
1488 | Message(M_WARNING,"site %s: site is mobile but so are we" | |
1489 | " -> ignoring this site\n", st->remotename); | |
558fa3fb SE |
1490 | free(st); |
1491 | return NULL; | |
1492 | } | |
dba19f84 | 1493 | |
58650a70 RK |
1494 | assert(index_sequence < 0xffffffffUL); |
1495 | st->index = ++index_sequence; | |
469fd1d9 | 1496 | st->netlink=find_cl_if(dict,"link",CL_NETLINK,True,"site",loc); |
59533c16 IJ |
1497 | |
1498 | list_t *comms_cfg=dict_lookup(dict,"comm"); | |
39a6b1e2 | 1499 | if (!comms_cfg) cfgfatal(loc,"site","closure list \"comm\" not found\n"); |
59533c16 IJ |
1500 | st->ncomms=list_length(comms_cfg); |
1501 | st->comms=safe_malloc_ary(sizeof(*st->comms),st->ncomms,"comms"); | |
1502 | assert(st->ncomms); | |
1503 | for (i=0; i<st->ncomms; i++) { | |
1504 | item_t *item=list_elem(comms_cfg,i); | |
39a6b1e2 IJ |
1505 | if (item->type!=t_closure) |
1506 | cfgfatal(loc,"site","comm is not a closure\n"); | |
59533c16 | 1507 | closure_t *cl=item->data.closure; |
39a6b1e2 | 1508 | if (cl->type!=CL_COMM) cfgfatal(loc,"site","comm closure wrong type\n"); |
59533c16 IJ |
1509 | st->comms[i]=cl->interface; |
1510 | } | |
1511 | ||
2fe58dfd SE |
1512 | st->resolver=find_cl_if(dict,"resolver",CL_RESOLVER,True,"site",loc); |
1513 | st->log=find_cl_if(dict,"log",CL_LOG,True,"site",loc); | |
1514 | st->random=find_cl_if(dict,"random",CL_RANDOMSRC,True,"site",loc); | |
1515 | ||
2fe58dfd | 1516 | st->privkey=find_cl_if(dict,"local-key",CL_RSAPRIVKEY,True,"site",loc); |
2fe58dfd | 1517 | st->address=dict_read_string(dict, "address", False, "site", loc); |
3454dce4 SE |
1518 | if (st->address) |
1519 | st->remoteport=dict_read_number(dict,"port",True,"site",loc,0); | |
1520 | else st->remoteport=0; | |
2fe58dfd SE |
1521 | st->pubkey=find_cl_if(dict,"key",CL_RSAPUBKEY,True,"site",loc); |
1522 | ||
1523 | st->transform= | |
1524 | find_cl_if(dict,"transform",CL_TRANSFORM,True,"site",loc); | |
1525 | ||
1526 | st->dh=find_cl_if(dict,"dh",CL_DH,True,"site",loc); | |
1527 | st->hash=find_cl_if(dict,"hash",CL_HASH,True,"site",loc); | |
1528 | ||
e57264d6 IJ |
1529 | #define DEFAULT(D) (st->peer_mobile || local_mobile \ |
1530 | ? DEFAULT_MOBILE_##D : DEFAULT_##D) | |
e7f8ec2a | 1531 | #define CFG_NUMBER(k,D) dict_read_number(dict,(k),False,"site",loc,DEFAULT(D)); |
c27ca22f | 1532 | |
e7f8ec2a IJ |
1533 | st->key_lifetime= CFG_NUMBER("key-lifetime", KEY_LIFETIME); |
1534 | st->setup_retries= CFG_NUMBER("setup-retries", SETUP_RETRIES); | |
1535 | st->setup_retry_interval= CFG_NUMBER("setup-timeout", SETUP_RETRY_INTERVAL); | |
1536 | st->wait_timeout= CFG_NUMBER("wait-time", WAIT_TIME); | |
1537 | ||
446353cd IJ |
1538 | st->mobile_peer_expiry= dict_read_number( |
1539 | dict,"mobile-peer-expiry",False,"site",loc,DEFAULT_MOBILE_PEER_EXPIRY); | |
1540 | ||
1541 | st->transport_peers_max= !st->peer_mobile ? 1 : dict_read_number( | |
1542 | dict,"mobile-peers-max",False,"site",loc,DEFAULT_MOBILE_PEERS_MAX); | |
1543 | if (st->transport_peers_max<1 || | |
1544 | st->transport_peers_max>=MAX_MOBILE_PEERS_MAX) { | |
1545 | cfgfatal(loc,"site","mobile-peers-max must be in range 1.." | |
1546 | STRING(MAX_MOBILE_PEERS_MAX) "\n"); | |
1547 | } | |
1548 | ||
e7f8ec2a | 1549 | if (st->key_lifetime < DEFAULT(KEY_RENEGOTIATE_GAP)*2) |
c27ca22f IJ |
1550 | st->key_renegotiate_time=st->key_lifetime/2; |
1551 | else | |
e7f8ec2a | 1552 | st->key_renegotiate_time=st->key_lifetime-DEFAULT(KEY_RENEGOTIATE_GAP); |
9d3a4132 | 1553 | st->key_renegotiate_time=dict_read_number( |
cce0051f | 1554 | dict,"renegotiate-time",False,"site",loc,st->key_renegotiate_time); |
9d3a4132 SE |
1555 | if (st->key_renegotiate_time > st->key_lifetime) { |
1556 | cfgfatal(loc,"site", | |
1557 | "renegotiate-time must be less than key-lifetime\n"); | |
1558 | } | |
9d3a4132 SE |
1559 | |
1560 | st->log_events=string_list_to_word(dict_lookup(dict,"log-events"), | |
1561 | log_event_table,"site"); | |
2fe58dfd | 1562 | |
4efd681a SE |
1563 | st->tunname=safe_malloc(strlen(st->localname)+strlen(st->remotename)+5, |
1564 | "site_apply"); | |
1565 | sprintf(st->tunname,"%s<->%s",st->localname,st->remotename); | |
1566 | ||
2fe58dfd | 1567 | /* The information we expect to see in incoming messages of type 1 */ |
59230b9b IJ |
1568 | /* fixme: lots of unchecked overflows here, but the results are only |
1569 | corrupted packets rather than undefined behaviour */ | |
2fe58dfd SE |
1570 | st->setup_priority=(strcmp(st->localname,st->remotename)>0); |
1571 | ||
1572 | buffer_new(&st->buffer,SETUP_BUFFER_LEN); | |
1573 | ||
05f39b4d IJ |
1574 | buffer_new(&st->scratch,0); |
1575 | BUF_ALLOC(&st->scratch,"site:scratch"); | |
1576 | ||
2fe58dfd SE |
1577 | /* We are interested in poll(), but only for timeouts. We don't have |
1578 | any fds of our own. */ | |
1579 | register_for_poll(st, site_beforepoll, site_afterpoll, 0, "site"); | |
1580 | st->timeout=0; | |
1581 | ||
19e9a588 | 1582 | st->current.key_timeout=0; |
02b0959b | 1583 | st->auxiliary_key.key_timeout=0; |
446353cd IJ |
1584 | transport_peers_clear(st,&st->peers); |
1585 | transport_peers_clear(st,&st->setup_peers); | |
2fe58dfd SE |
1586 | /* XXX mlock these */ |
1587 | st->dhsecret=safe_malloc(st->dh->len,"site:dhsecret"); | |
7c9ca4bd IJ |
1588 | st->sharedsecretlen=st->transform->keylen?:st->dh->ceil_len; |
1589 | st->sharedsecret=safe_malloc(st->sharedsecretlen,"site:sharedsecret"); | |
2fe58dfd | 1590 | |
59533c16 IJ |
1591 | /* We need to compute some properties of our comms */ |
1592 | #define COMPUTE_WORST(pad) \ | |
1593 | int worst_##pad=0; \ | |
1594 | for (i=0; i<st->ncomms; i++) { \ | |
1595 | int thispad=st->comms[i]->pad; \ | |
1596 | if (thispad > worst_##pad) \ | |
1597 | worst_##pad=thispad; \ | |
1598 | } | |
1599 | COMPUTE_WORST(min_start_pad) | |
1600 | COMPUTE_WORST(min_end_pad) | |
1601 | ||
2fe58dfd | 1602 | /* We need to register the remote networks with the netlink device */ |
469fd1d9 | 1603 | st->netlink->reg(st->netlink->st, site_outgoing, st, |
ff05a229 | 1604 | st->transform->max_start_pad+(4*4)+ |
59533c16 IJ |
1605 | worst_min_start_pad, |
1606 | st->transform->max_end_pad+worst_min_end_pad); | |
ff05a229 | 1607 | |
59533c16 IJ |
1608 | for (i=0; i<st->ncomms; i++) |
1609 | st->comms[i]->request_notify(st->comms[i]->st, st, site_incoming); | |
2fe58dfd | 1610 | |
19e9a588 | 1611 | st->current.transform=st->transform->create(st->transform->st); |
02b0959b | 1612 | st->auxiliary_key.transform=st->transform->create(st->transform->st); |
2fe58dfd | 1613 | st->new_transform=st->transform->create(st->transform->st); |
bd98cd6b | 1614 | st->auxiliary_is_new=0; |
2fe58dfd SE |
1615 | |
1616 | enter_state_stop(st); | |
1617 | ||
794f2398 SE |
1618 | add_hook(PHASE_SHUTDOWN,site_phase_hook,st); |
1619 | ||
2fe58dfd SE |
1620 | return new_closure(&st->cl); |
1621 | } | |
1622 | ||
2fe58dfd SE |
1623 | void site_module(dict_t *dict) |
1624 | { | |
1625 | add_closure(dict,"site",site_apply); | |
1626 | } | |
446353cd IJ |
1627 | |
1628 | ||
1629 | /***** TRANSPORT PEERS definitions *****/ | |
1630 | ||
1631 | static void transport_peers_debug(struct site *st, transport_peers *dst, | |
1632 | const char *didwhat, | |
1633 | int nargs, const struct comm_addr *args, | |
1634 | size_t stride) { | |
1635 | int i; | |
1636 | char *argp; | |
1637 | ||
1638 | if (!(st->log_events & LOG_PEER_ADDRS)) | |
1639 | return; /* an optimisation */ | |
1640 | ||
1641 | slog(st, LOG_PEER_ADDRS, "peers (%s) %s nargs=%d => npeers=%d", | |
1642 | (dst==&st->peers ? "data" : | |
1643 | dst==&st->setup_peers ? "setup" : "UNKNOWN"), | |
1644 | didwhat, nargs, dst->npeers); | |
1645 | ||
1646 | for (i=0, argp=(void*)args; | |
1647 | i<nargs; | |
1648 | i++, (argp+=stride?stride:sizeof(*args))) { | |
1649 | const struct comm_addr *ca=(void*)argp; | |
1650 | slog(st, LOG_PEER_ADDRS, " args: addrs[%d]=%s", | |
1651 | i, ca->comm->addr_to_string(ca->comm->st,ca)); | |
1652 | } | |
1653 | for (i=0; i<dst->npeers; i++) { | |
1654 | struct timeval diff; | |
1655 | timersub(tv_now,&dst->peers[i].last,&diff); | |
1656 | const struct comm_addr *ca=&dst->peers[i].addr; | |
1657 | slog(st, LOG_PEER_ADDRS, " peers: addrs[%d]=%s T-%ld.%06ld", | |
1658 | i, ca->comm->addr_to_string(ca->comm->st,ca), | |
1659 | (unsigned long)diff.tv_sec, (unsigned long)diff.tv_usec); | |
1660 | } | |
1661 | } | |
1662 | ||
1663 | static int transport_peer_compar(const void *av, const void *bv) { | |
1664 | const transport_peer *a=av; | |
1665 | const transport_peer *b=bv; | |
1666 | /* put most recent first in the array */ | |
1667 | if (timercmp(&a->last, &b->last, <)) return +1; | |
1668 | if (timercmp(&a->last, &b->last, >)) return -11; | |
1669 | return 0; | |
1670 | } | |
1671 | ||
1672 | static void transport_peers_expire(struct site *st, transport_peers *peers) { | |
1673 | /* peers must be sorted first */ | |
1674 | int previous_peers=peers->npeers; | |
1675 | struct timeval oldest; | |
1676 | oldest.tv_sec = tv_now->tv_sec - st->mobile_peer_expiry; | |
1677 | oldest.tv_usec = tv_now->tv_usec; | |
1678 | while (peers->npeers>1 && | |
1679 | timercmp(&peers->peers[peers->npeers-1].last, &oldest, <)) | |
1680 | peers->npeers--; | |
1681 | if (peers->npeers != previous_peers) | |
1682 | transport_peers_debug(st,peers,"expire", 0,0,0); | |
1683 | } | |
1684 | ||
1685 | static void transport_record_peer(struct site *st, transport_peers *peers, | |
1686 | const struct comm_addr *addr, const char *m) { | |
1687 | int slot, changed=0; | |
1688 | ||
1689 | for (slot=0; slot<peers->npeers; slot++) | |
1690 | if (!memcmp(&peers->peers[slot].addr, addr, sizeof(*addr))) | |
1691 | goto found; | |
1692 | ||
1693 | changed=1; | |
1694 | if (peers->npeers==st->transport_peers_max) | |
1695 | slot=st->transport_peers_max; | |
1696 | else | |
1697 | slot=peers->npeers++; | |
1698 | ||
1699 | found: | |
1700 | peers->peers[slot].addr=*addr; | |
1701 | peers->peers[slot].last=*tv_now; | |
1702 | ||
1703 | if (peers->npeers>1) | |
1704 | qsort(peers->peers, peers->npeers, | |
1705 | sizeof(*peers->peers), transport_peer_compar); | |
1706 | ||
1707 | if (changed || peers->npeers!=1) | |
1708 | transport_peers_debug(st,peers,m, 1,addr,0); | |
1709 | transport_peers_expire(st, peers); | |
1710 | } | |
1711 | ||
1712 | static bool_t transport_compute_setupinit_peers(struct site *st, | |
1713 | const struct comm_addr *configured_addr /* 0 if none or not found */) { | |
1714 | ||
1715 | if (!configured_addr && !transport_peers_valid(&st->peers)) | |
1716 | return False; | |
1717 | ||
1718 | slog(st,LOG_SETUP_INIT, | |
1719 | (!configured_addr ? "using only %d old peer address(es)" | |
1720 | : "using configured address, and/or perhaps %d old peer address(es)"), | |
1721 | st->peers); | |
1722 | ||
1723 | /* Non-mobile peers havve st->peers.npeers==0 or ==1, since they | |
1724 | * have transport_peers_max==1. The effect is that this code | |
1725 | * always uses the configured address if supplied, or otherwise | |
1726 | * the existing data peer if one exists; this is as desired. */ | |
1727 | ||
1728 | transport_peers_copy(st,&st->setup_peers,&st->peers); | |
1729 | ||
1730 | if (configured_addr) | |
1731 | transport_record_peer(st,&st->setup_peers,configured_addr,"setupinit"); | |
1732 | ||
1733 | assert(transport_peers_valid(&st->setup_peers)); | |
1734 | return True; | |
1735 | } | |
1736 | ||
1737 | static void transport_setup_msgok(struct site *st, const struct comm_addr *a) { | |
1738 | if (st->peer_mobile) | |
1739 | transport_record_peer(st,&st->setup_peers,a,"setupmsg"); | |
1740 | } | |
1741 | static void transport_data_msgok(struct site *st, const struct comm_addr *a) { | |
1742 | if (st->peer_mobile) | |
1743 | transport_record_peer(st,&st->peers,a,"datamsg"); | |
1744 | } | |
1745 | ||
1746 | static int transport_peers_valid(transport_peers *peers) { | |
1747 | return peers->npeers; | |
1748 | } | |
1749 | static void transport_peers_clear(struct site *st, transport_peers *peers) { | |
1750 | peers->npeers= 0; | |
1751 | transport_peers_debug(st,peers,"clear",0,0,0); | |
1752 | } | |
1753 | static void transport_peers_copy(struct site *st, transport_peers *dst, | |
1754 | const transport_peers *src) { | |
1755 | dst->npeers=src->npeers; | |
1756 | memcpy(dst->peers, src->peers, sizeof(*dst->peers) * dst->npeers); | |
1757 | transport_peers_debug(st,dst,"copy", | |
a620a048 | 1758 | src->npeers, &src->peers->addr, sizeof(*src->peers)); |
446353cd IJ |
1759 | } |
1760 | ||
1761 | void transport_xmit(struct site *st, transport_peers *peers, | |
1762 | struct buffer_if *buf, bool_t candebug) { | |
1763 | int slot; | |
1764 | transport_peers_expire(st, peers); | |
1765 | for (slot=0; slot<peers->npeers; slot++) { | |
1766 | transport_peer *peer=&peers->peers[slot]; | |
1767 | if (candebug) | |
1768 | dump_packet(st, buf, &peer->addr, False); | |
1769 | peer->addr.comm->sendmsg(peer->addr.comm->st, buf, &peer->addr); | |
1770 | } | |
1771 | } | |
1772 | ||
1773 | /***** END of transport peers declarations *****/ |