2 * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License v2 as published by
6 * the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
27 #include <sys/ioctl.h>
28 #include <sys/socket.h>
29 #include <arpa/inet.h>
30 #include <netinet/in.h>
33 #include <net/ethernet.h>
39 #define ALL_DHCPV6_RELAYS {{{0xff, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,\
40 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x02}}}
41 #define DHCPV6_CLIENT_PORT 546
42 #define DHCPV6_SERVER_PORT 547
43 #define DHCPV6_DUID_LLADDR 3
44 #define DHCPV6_REQ_DELAY 1
47 static bool dhcpv6_response_is_valid(const void *buf
, ssize_t len
,
48 const uint8_t transaction
[3], enum dhcpv6_msg type
,
49 const struct in6_addr
*daddr
);
51 static int dhcpv6_parse_ia(void *opt
, void *end
);
53 static int dhcpv6_calc_refresh_timers(void);
54 static void dhcpv6_handle_status_code(_unused
const enum dhcpv6_msg orig
,
55 const uint16_t code
, const void *status_msg
, const int len
,
57 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig
,
58 const struct dhcpv6_ia_hdr
*ia_hdr
, const uint16_t code
,
59 const void *status_msg
, const int len
,
60 bool handled_status_codes
[_DHCPV6_Status_Max
],
62 static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand
*cand
);
63 static void dhcpv6_clear_all_server_cand(void);
65 static reply_handler dhcpv6_handle_reply
;
66 static reply_handler dhcpv6_handle_advert
;
67 static reply_handler dhcpv6_handle_rebind_reply
;
68 static reply_handler dhcpv6_handle_reconfigure
;
69 static int dhcpv6_commit_advert(void);
73 // RFC 3315 - 5.5 Timeout and Delay values
74 static struct dhcpv6_retx dhcpv6_retx
[_DHCPV6_MSG_MAX
] = {
75 [DHCPV6_MSG_UNKNOWN
] = {false, 1, 120, 0, "<POLL>",
76 dhcpv6_handle_reconfigure
, NULL
},
77 [DHCPV6_MSG_SOLICIT
] = {true, 1, 3600, 0, "SOLICIT",
78 dhcpv6_handle_advert
, dhcpv6_commit_advert
},
79 [DHCPV6_MSG_REQUEST
] = {true, 1, 30, 10, "REQUEST",
80 dhcpv6_handle_reply
, NULL
},
81 [DHCPV6_MSG_RENEW
] = {false, 10, 600, 0, "RENEW",
82 dhcpv6_handle_reply
, NULL
},
83 [DHCPV6_MSG_REBIND
] = {false, 10, 600, 0, "REBIND",
84 dhcpv6_handle_rebind_reply
, NULL
},
85 [DHCPV6_MSG_RELEASE
] = {false, 1, 0, 5, "RELEASE", NULL
, NULL
},
86 [DHCPV6_MSG_DECLINE
] = {false, 1, 0, 5, "DECLINE", NULL
, NULL
},
87 [DHCPV6_MSG_INFO_REQ
] = {true, 1, 120, 0, "INFOREQ",
88 dhcpv6_handle_reply
, NULL
},
94 static int ifindex
= -1;
95 static int64_t t1
= 0, t2
= 0, t3
= 0;
98 static int request_prefix
= -1;
99 static enum odhcp6c_ia_mode na_mode
= IA_MODE_NONE
, pd_mode
= IA_MODE_NONE
;
100 static bool accept_reconfig
= false;
101 // Server unicast address
102 static struct in6_addr server_addr
= IN6ADDR_ANY_INIT
;
105 static uint8_t reconf_key
[16];
108 int init_dhcpv6(const char *ifname
, int request_pd
, int sol_timeout
)
110 request_prefix
= request_pd
;
111 dhcpv6_retx
[DHCPV6_MSG_SOLICIT
].max_timeo
= sol_timeout
;
113 sock
= socket(AF_INET6
, SOCK_DGRAM
| SOCK_CLOEXEC
, IPPROTO_UDP
);
119 strncpy(ifr
.ifr_name
, ifname
, sizeof(ifr
.ifr_name
));
120 if (ioctl(sock
, SIOCGIFINDEX
, &ifr
) < 0)
122 ifindex
= ifr
.ifr_ifindex
;
124 // Create client DUID
125 size_t client_id_len
;
126 odhcp6c_get_state(STATE_CLIENT_ID
, &client_id_len
);
127 if (client_id_len
== 0) {
128 uint8_t duid
[14] = {0, DHCPV6_OPT_CLIENTID
, 0, 10, 0,
129 DHCPV6_DUID_LLADDR
, 0, 1};
131 if (ioctl(sock
, SIOCGIFHWADDR
, &ifr
) >= 0)
132 memcpy(&duid
[8], ifr
.ifr_hwaddr
.sa_data
, ETHER_ADDR_LEN
);
134 uint8_t zero
[ETHER_ADDR_LEN
] = {0, 0, 0, 0, 0, 0};
135 struct ifreq ifs
[100], *ifp
, *ifend
;
138 ifc
.ifc_len
= sizeof(ifs
);
140 if (!memcmp(&duid
[8], zero
, ETHER_ADDR_LEN
) &&
141 ioctl(sock
, SIOCGIFCONF
, &ifc
) >= 0) {
142 // If our interface doesn't have an address...
143 ifend
= ifs
+ (ifc
.ifc_len
/ sizeof(struct ifreq
));
144 for (ifp
= ifc
.ifc_req
; ifp
< ifend
&&
145 !memcmp(&duid
[8], zero
, ETHER_ADDR_LEN
); ifp
++) {
146 memcpy(ifr
.ifr_name
, ifp
->ifr_name
,
147 sizeof(ifr
.ifr_name
));
148 if (ioctl(sock
, SIOCGIFHWADDR
, &ifr
) < 0)
151 memcpy(&duid
[8], ifr
.ifr_hwaddr
.sa_data
,
156 odhcp6c_add_state(STATE_CLIENT_ID
, duid
, sizeof(duid
));
161 htons(DHCPV6_OPT_SIP_SERVER_D
),
162 htons(DHCPV6_OPT_SIP_SERVER_A
),
163 htons(DHCPV6_OPT_DNS_SERVERS
),
164 htons(DHCPV6_OPT_DNS_DOMAIN
),
165 htons(DHCPV6_OPT_UNICAST
),
166 htons(DHCPV6_OPT_NTP_SERVER
),
167 htons(DHCPV6_OPT_AFTR_NAME
),
168 htons(DHCPV6_OPT_PD_EXCLUDE
),
169 #ifdef EXT_PREFIX_CLASS
170 htons(DHCPV6_OPT_PREFIX_CLASS
),
173 odhcp6c_add_state(STATE_ORO
, oro
, sizeof(oro
));
175 // Configure IPv6-options
177 setsockopt(sock
, IPPROTO_IPV6
, IPV6_V6ONLY
, &val
, sizeof(val
));
178 setsockopt(sock
, SOL_SOCKET
, SO_REUSEADDR
, &val
, sizeof(val
));
179 setsockopt(sock
, IPPROTO_IPV6
, IPV6_RECVPKTINFO
, &val
, sizeof(val
));
181 setsockopt(sock
, IPPROTO_IPV6
, IPV6_MULTICAST_LOOP
, &val
, sizeof(val
));
182 setsockopt(sock
, SOL_SOCKET
, SO_BINDTODEVICE
, ifname
, strlen(ifname
));
184 struct sockaddr_in6 client_addr
= { .sin6_family
= AF_INET6
,
185 .sin6_port
= htons(DHCPV6_CLIENT_PORT
), .sin6_flowinfo
= 0 };
186 if (bind(sock
, (struct sockaddr
*)&client_addr
, sizeof(client_addr
)) < 0)
193 void dhcpv6_set_ia_mode(enum odhcp6c_ia_mode na
, enum odhcp6c_ia_mode pd
)
200 static void dhcpv6_send(enum dhcpv6_msg type
, uint8_t trid
[3], uint32_t ecs
)
204 gethostname(fqdn_buf
, sizeof(fqdn_buf
));
211 size_t fqdn_len
= 5 + dn_comp(fqdn_buf
, fqdn
.data
,
212 sizeof(fqdn
.data
), NULL
, NULL
);
213 fqdn
.type
= htons(DHCPV6_OPT_FQDN
);
214 fqdn
.len
= htons(fqdn_len
- 4);
220 void *cl_id
= odhcp6c_get_state(STATE_CLIENT_ID
, &cl_id_len
);
224 void *srv_id
= odhcp6c_get_state(STATE_SERVER_ID
, &srv_id_len
);
227 size_t ia_pd_entries
, ia_pd_len
= 0;
228 struct odhcp6c_entry
*e
= odhcp6c_get_state(STATE_IA_PD
, &ia_pd_entries
);
229 ia_pd_entries
/= sizeof(*e
);
230 struct dhcpv6_ia_hdr hdr_ia_pd
= {
231 htons(DHCPV6_OPT_IA_PD
),
232 htons(sizeof(hdr_ia_pd
) - 4),
237 uint8_t *ia_pd
= alloca(ia_pd_entries
* (sizeof(struct dhcpv6_ia_prefix
) + 10));
238 for (size_t i
= 0; i
< ia_pd_entries
; ++i
) {
240 if (e
[i
].priority
> 0)
241 ex_len
= ((e
[i
].priority
- e
[i
].length
- 1) / 8) + 6;
243 struct dhcpv6_ia_prefix p
= {
244 .type
= htons(DHCPV6_OPT_IA_PREFIX
),
245 .len
= htons(sizeof(p
) - 4U + ex_len
),
246 .prefix
= e
[i
].length
,
250 memcpy(ia_pd
+ ia_pd_len
, &p
, sizeof(p
));
251 ia_pd_len
+= sizeof(p
);
254 ia_pd
[ia_pd_len
++] = 0;
255 ia_pd
[ia_pd_len
++] = DHCPV6_OPT_PD_EXCLUDE
;
256 ia_pd
[ia_pd_len
++] = 0;
257 ia_pd
[ia_pd_len
++] = ex_len
- 4;
258 ia_pd
[ia_pd_len
++] = e
[i
].priority
;
260 uint32_t excl
= ntohl(e
[i
].router
.s6_addr32
[1]);
261 excl
>>= (64 - e
[i
].priority
);
262 excl
<<= 8 - ((e
[i
].priority
- e
[i
].length
) % 8);
264 for (size_t i
= ex_len
- 5; i
> 0; --i
, excl
>>= 8)
265 ia_pd
[ia_pd_len
+ i
] = excl
& 0xff;
266 ia_pd_len
+= ex_len
- 5;
270 struct dhcpv6_ia_prefix pref
= {
271 .type
= htons(DHCPV6_OPT_IA_PREFIX
),
272 .len
= htons(25), .prefix
= request_prefix
274 if (request_prefix
> 0 && ia_pd_len
== 0 && type
== DHCPV6_MSG_SOLICIT
) {
275 ia_pd
= (uint8_t*)&pref
;
276 ia_pd_len
= sizeof(pref
);
278 hdr_ia_pd
.len
= htons(ntohs(hdr_ia_pd
.len
) + ia_pd_len
);
281 size_t ia_na_entries
, ia_na_len
= 0;
283 e
= odhcp6c_get_state(STATE_IA_NA
, &ia_na_entries
);
284 ia_na_entries
/= sizeof(*e
);
286 struct dhcpv6_ia_hdr hdr_ia_na
= {
287 htons(DHCPV6_OPT_IA_NA
),
288 htons(sizeof(hdr_ia_na
) - 4),
292 struct dhcpv6_ia_addr pa
[ia_na_entries
];
293 for (size_t i
= 0; i
< ia_na_entries
; ++i
) {
294 pa
[i
].type
= htons(DHCPV6_OPT_IA_ADDR
);
295 pa
[i
].len
= htons(sizeof(pa
[i
]) - 4U);
296 pa
[i
].addr
= e
[i
].target
;
302 ia_na_len
= sizeof(pa
);
303 hdr_ia_na
.len
= htons(ntohs(hdr_ia_na
.len
) + ia_na_len
);
305 // Reconfigure Accept
309 } reconf_accept
= {htons(DHCPV6_OPT_RECONF_ACCEPT
), 0};
311 // Request Information Refresh
312 uint16_t oro_refresh
= htons(DHCPV6_OPT_INFO_REFRESH
);
316 void *oro
= odhcp6c_get_state(STATE_ORO
, &oro_len
);
320 uint16_t elapsed_type
;
321 uint16_t elapsed_len
;
322 uint16_t elapsed_value
;
326 type
, {trid
[0], trid
[1], trid
[2]},
327 htons(DHCPV6_OPT_ELAPSED
), htons(2),
328 htons((ecs
> 0xffff) ? 0xffff : ecs
),
329 htons(DHCPV6_OPT_ORO
), htons(oro_len
),
332 struct iovec iov
[] = {
337 {srv_id
, srv_id_len
},
338 {&reconf_accept
, sizeof(reconf_accept
)},
340 {&hdr_ia_na
, sizeof(hdr_ia_na
)},
342 {&hdr_ia_pd
, sizeof(hdr_ia_pd
)},
346 size_t cnt
= ARRAY_SIZE(iov
);
347 if (type
== DHCPV6_MSG_INFO_REQ
) {
349 iov
[2].iov_len
= sizeof(oro_refresh
);
350 hdr
.oro_len
= htons(oro_len
+ sizeof(oro_refresh
));
351 } else if (!request_prefix
) {
355 // Disable IAs if not used
356 if (type
!= DHCPV6_MSG_SOLICIT
) {
364 if (na_mode
== IA_MODE_NONE
)
367 struct sockaddr_in6 srv
= {AF_INET6
, htons(DHCPV6_SERVER_PORT
),
368 0, ALL_DHCPV6_RELAYS
, ifindex
};
369 struct msghdr msg
= {&srv
, sizeof(srv
), iov
, cnt
, NULL
, 0, 0};
372 case DHCPV6_MSG_REQUEST
:
373 case DHCPV6_MSG_RENEW
:
374 case DHCPV6_MSG_RELEASE
:
375 case DHCPV6_MSG_DECLINE
:
376 if (!IN6_IS_ADDR_UNSPECIFIED(&server_addr
) &&
377 odhcp6c_addr_in_scope(&server_addr
)) {
378 srv
.sin6_addr
= server_addr
;
379 if (!IN6_IS_ADDR_LINKLOCAL(&server_addr
))
380 srv
.sin6_scope_id
= 0;
387 if (sendmsg(sock
, &msg
, 0) < 0) {
388 char in6_str
[INET6_ADDRSTRLEN
];
390 syslog(LOG_ERR
, "Failed to send DHCPV6 message to %s (%s)",
391 inet_ntop(AF_INET6
, (const void *)&srv
.sin6_addr
,
392 in6_str
, sizeof(in6_str
)), strerror(errno
));
397 static int64_t dhcpv6_rand_delay(int64_t time
)
400 odhcp6c_random(&random
, sizeof(random
));
401 return (time
* ((int64_t)random
% 1000LL)) / 10000LL;
405 int dhcpv6_request(enum dhcpv6_msg type
)
408 uint64_t timeout
= UINT32_MAX
;
409 struct dhcpv6_retx
*retx
= &dhcpv6_retx
[type
];
412 struct timespec ts
= {0, 0};
413 ts
.tv_nsec
= dhcpv6_rand_delay(10 * DHCPV6_REQ_DELAY
);
414 nanosleep(&ts
, NULL
);
417 if (type
== DHCPV6_MSG_UNKNOWN
)
419 else if (type
== DHCPV6_MSG_RENEW
)
420 timeout
= (t2
> t1
) ? t2
- t1
: 0;
421 else if (type
== DHCPV6_MSG_REBIND
)
422 timeout
= (t3
> t2
) ? t3
- t2
: 0;
427 syslog(LOG_NOTICE
, "Starting %s transaction (timeout %llus, max rc %d)",
428 retx
->name
, (unsigned long long)timeout
, retx
->max_rc
);
430 uint64_t start
= odhcp6c_get_milli_time(), round_start
= start
, elapsed
;
432 // Generate transaction ID
433 uint8_t trid
[3] = {0, 0, 0};
434 if (type
!= DHCPV6_MSG_UNKNOWN
)
435 odhcp6c_random(trid
, sizeof(trid
));
441 int64_t delay
= dhcpv6_rand_delay(retx
->init_timeo
* 1000);
443 // First RT MUST be strictly greater than IRT for solicit messages (RFC3313 17.1.2)
444 while (type
== DHCPV6_MSG_SOLICIT
&& delay
<= 0)
445 delay
= dhcpv6_rand_delay(retx
->init_timeo
* 1000);
447 rto
= (retx
->init_timeo
* 1000 + delay
);
450 rto
= (2 * rto
+ dhcpv6_rand_delay(rto
));
452 if (retx
->max_timeo
&& (rto
>= retx
->max_timeo
* 1000))
453 rto
= retx
->max_timeo
* 1000 +
454 dhcpv6_rand_delay(retx
->max_timeo
* 1000);
456 // Calculate end for this round and elapsed time
457 uint64_t round_end
= round_start
+ rto
;
458 elapsed
= round_start
- start
;
460 // Don't wait too long
461 if (round_end
- start
> timeout
* 1000)
462 round_end
= timeout
* 1000 + start
;
464 // Built and send package
465 if (type
!= DHCPV6_MSG_UNKNOWN
) {
466 if (type
!= DHCPV6_MSG_SOLICIT
)
467 syslog(LOG_NOTICE
, "Send %s message (elapsed %llums, rc %d)",
468 retx
->name
, (unsigned long long)elapsed
, rc
);
469 dhcpv6_send(type
, trid
, elapsed
/ 10);
474 for (; len
< 0 && (round_start
< round_end
);
475 round_start
= odhcp6c_get_milli_time()) {
476 uint8_t buf
[1536], cmsg_buf
[CMSG_SPACE(sizeof(struct in6_pktinfo
))];
477 struct iovec iov
= {buf
, sizeof(buf
)};
478 struct msghdr msg
= {NULL
, 0, &iov
, 1,
479 cmsg_buf
, sizeof(cmsg_buf
), 0};
480 struct in6_pktinfo
*pktinfo
= NULL
;
482 // Check for pending signal
483 if (odhcp6c_signal_process())
486 // Set timeout for receiving
487 uint64_t t
= round_end
- round_start
;
488 struct timeval timeout
= {t
/ 1000, (t
% 1000) * 1000};
489 setsockopt(sock
, SOL_SOCKET
, SO_RCVTIMEO
,
490 &timeout
, sizeof(timeout
));
493 len
= recvmsg(sock
, &msg
, 0);
497 for (struct cmsghdr
*ch
= CMSG_FIRSTHDR(&msg
); ch
!= NULL
;
498 ch
= CMSG_NXTHDR(&msg
, ch
)) {
499 if (ch
->cmsg_level
== SOL_IPV6
&&
500 ch
->cmsg_type
== IPV6_PKTINFO
) {
501 pktinfo
= (struct in6_pktinfo
*)CMSG_DATA(ch
);
506 if (pktinfo
== NULL
) {
511 if (!dhcpv6_response_is_valid(buf
, len
, trid
,
512 type
, &pktinfo
->ipi6_addr
)) {
517 uint8_t *opt
= &buf
[4];
518 uint8_t *opt_end
= opt
+ len
- 4;
520 round_start
= odhcp6c_get_milli_time();
521 elapsed
= round_start
- start
;
522 syslog(LOG_NOTICE
, "Got a valid reply after "
523 "%llums", (unsigned long long)elapsed
);
525 if (retx
->handler_reply
)
526 len
= retx
->handler_reply(type
, rc
, opt
, opt_end
);
528 if (len
> 0 && round_end
- round_start
> 1000)
529 round_end
= 1000 + round_start
;
533 if (retx
->handler_finish
)
534 len
= retx
->handler_finish();
535 } while (len
< 0 && ((elapsed
/ 1000 < timeout
) && (!retx
->max_rc
|| rc
< retx
->max_rc
)));
540 // Message validation checks according to RFC3315 chapter 15
541 static bool dhcpv6_response_is_valid(const void *buf
, ssize_t len
,
542 const uint8_t transaction
[3], enum dhcpv6_msg type
,
543 const struct in6_addr
*daddr
)
545 const struct dhcpv6_header
*rep
= buf
;
546 if (len
< (ssize_t
)sizeof(*rep
) || memcmp(rep
->tr_id
,
547 transaction
, sizeof(rep
->tr_id
)))
548 return false; // Invalid reply
550 if (type
== DHCPV6_MSG_SOLICIT
) {
551 if (rep
->msg_type
!= DHCPV6_MSG_ADVERT
&&
552 rep
->msg_type
!= DHCPV6_MSG_REPLY
)
554 } else if (type
== DHCPV6_MSG_UNKNOWN
) {
555 if (!accept_reconfig
|| rep
->msg_type
!= DHCPV6_MSG_RECONF
)
557 } else if (rep
->msg_type
!= DHCPV6_MSG_REPLY
) {
561 uint8_t *end
= ((uint8_t*)buf
) + len
, *odata
,
562 rcmsg
= DHCPV6_MSG_UNKNOWN
;
563 uint16_t otype
, olen
;
564 bool clientid_ok
= false, serverid_ok
= false, rcauth_ok
= false,
565 ia_present
= false, options_valid
= true;
567 size_t client_id_len
, server_id_len
;
568 void *client_id
= odhcp6c_get_state(STATE_CLIENT_ID
, &client_id_len
);
569 void *server_id
= odhcp6c_get_state(STATE_SERVER_ID
, &server_id_len
);
571 dhcpv6_for_each_option(&rep
[1], end
, otype
, olen
, odata
) {
572 if ((odata
+ olen
) > end
) {
573 options_valid
= false;
576 else if (otype
== DHCPV6_OPT_CLIENTID
) {
577 clientid_ok
= (olen
+ 4U == client_id_len
) && !memcmp(
578 &odata
[-4], client_id
, client_id_len
);
579 } else if (otype
== DHCPV6_OPT_SERVERID
) {
581 serverid_ok
= (olen
+ 4U == server_id_len
) && !memcmp(
582 &odata
[-4], server_id
, server_id_len
);
585 } else if (otype
== DHCPV6_OPT_AUTH
&& olen
== -4 +
586 sizeof(struct dhcpv6_auth_reconfigure
)) {
587 struct dhcpv6_auth_reconfigure
*r
= (void*)&odata
[-4];
588 if (r
->protocol
!= 3 || r
->algorithm
!= 1 || r
->reconf_type
!= 2)
592 uint8_t serverhash
[16], secretbytes
[16], hash
[16];
593 memcpy(serverhash
, r
->key
, sizeof(serverhash
));
594 memset(r
->key
, 0, sizeof(r
->key
));
595 memcpy(secretbytes
, reconf_key
, sizeof(secretbytes
));
597 for (size_t i
= 0; i
< sizeof(secretbytes
); ++i
)
598 secretbytes
[i
] ^= 0x36;
601 md5_append(&md5
, secretbytes
, sizeof(secretbytes
));
602 md5_append(&md5
, buf
, len
);
603 md5_finish(&md5
, hash
);
605 for (size_t i
= 0; i
< sizeof(secretbytes
); ++i
) {
606 secretbytes
[i
] ^= 0x36;
607 secretbytes
[i
] ^= 0x5c;
611 md5_append(&md5
, secretbytes
, sizeof(secretbytes
));
612 md5_append(&md5
, hash
, 16);
613 md5_finish(&md5
, hash
);
615 rcauth_ok
= !memcmp(hash
, serverhash
, sizeof(hash
));
616 } else if (otype
== DHCPV6_OPT_RECONF_MESSAGE
&& olen
== 1) {
618 } else if ((otype
== DHCPV6_OPT_IA_PD
|| otype
== DHCPV6_OPT_IA_NA
)) {
620 if (olen
< sizeof(struct dhcpv6_ia_hdr
))
621 options_valid
= false;
623 else if ((otype
== DHCPV6_OPT_IA_ADDR
) || (otype
== DHCPV6_OPT_IA_PREFIX
) ||
624 (otype
== DHCPV6_OPT_PD_EXCLUDE
)) {
625 // Options are not allowed on global level
626 options_valid
= false;
633 if (type
== DHCPV6_MSG_INFO_REQ
&& ia_present
)
636 if (rep
->msg_type
== DHCPV6_MSG_RECONF
) {
637 if ((rcmsg
!= DHCPV6_MSG_RENEW
&& rcmsg
!= DHCPV6_MSG_INFO_REQ
) ||
638 (rcmsg
== DHCPV6_MSG_INFO_REQ
&& ia_present
) ||
639 !rcauth_ok
|| IN6_IS_ADDR_MULTICAST(daddr
))
643 return clientid_ok
&& serverid_ok
;
647 int dhcpv6_poll_reconfigure(void)
649 int ret
= dhcpv6_request(DHCPV6_MSG_UNKNOWN
);
651 ret
= dhcpv6_request(ret
);
657 static int dhcpv6_handle_reconfigure(_unused
enum dhcpv6_msg orig
, const int rc
,
658 const void *opt
, const void *end
)
660 uint16_t otype
, olen
;
661 uint8_t *odata
, msg
= DHCPV6_MSG_RENEW
;
662 dhcpv6_for_each_option(opt
, end
, otype
, olen
, odata
)
663 if (otype
== DHCPV6_OPT_RECONF_MESSAGE
&& olen
== 1 && (
664 odata
[0] == DHCPV6_MSG_RENEW
||
665 odata
[0] == DHCPV6_MSG_INFO_REQ
))
668 dhcpv6_handle_reply(DHCPV6_MSG_UNKNOWN
, rc
, NULL
, NULL
);
673 // Collect all advertised servers
674 static int dhcpv6_handle_advert(enum dhcpv6_msg orig
, const int rc
,
675 const void *opt
, const void *end
)
677 uint16_t olen
, otype
;
678 uint8_t *odata
, pref
= 0;
679 struct dhcpv6_server_cand cand
= {false, false, 0, 0, {0},
680 IN6ADDR_ANY_INIT
, NULL
, NULL
, 0, 0};
681 bool have_na
= false;
684 dhcpv6_for_each_option(opt
, end
, otype
, olen
, odata
) {
685 if (orig
== DHCPV6_MSG_SOLICIT
&&
686 (otype
== DHCPV6_OPT_IA_PD
|| otype
== DHCPV6_OPT_IA_NA
) &&
687 olen
> sizeof(struct dhcpv6_ia_hdr
)) {
688 struct dhcpv6_ia_hdr
*ia_hdr
= (void*)(&odata
[-4]);
689 dhcpv6_parse_ia(ia_hdr
, odata
+ olen
+ sizeof(*ia_hdr
));
692 if (otype
== DHCPV6_OPT_SERVERID
&& olen
<= 130) {
693 memcpy(cand
.duid
, odata
, olen
);
694 cand
.duid_len
= olen
;
695 } else if (otype
== DHCPV6_OPT_STATUS
&& olen
>= 2) {
696 int error
= ((int)odata
[0] << 8 | (int)odata
[1]);
699 case DHCPV6_NoPrefixAvail
:
700 // Status code on global level
701 if (pd_mode
== IA_MODE_FORCE
)
703 cand
.preference
-= 2000;
706 case DHCPV6_NoAddrsAvail
:
707 // Status code on global level
708 if (na_mode
== IA_MODE_FORCE
)
715 } else if (otype
== DHCPV6_OPT_PREF
&& olen
>= 1 &&
716 cand
.preference
>= 0) {
717 cand
.preference
= pref
= odata
[0];
718 } else if (otype
== DHCPV6_OPT_UNICAST
&& olen
== sizeof(cand
.server_addr
)) {
719 cand
.server_addr
= *(struct in6_addr
*)odata
;
720 } else if (otype
== DHCPV6_OPT_RECONF_ACCEPT
) {
721 cand
.wants_reconfigure
= true;
722 } else if (otype
== DHCPV6_OPT_IA_PD
&& request_prefix
) {
723 struct dhcpv6_ia_hdr
*h
= (struct dhcpv6_ia_hdr
*)&odata
[-4];
724 uint8_t *oend
= odata
+ olen
, *d
;
725 dhcpv6_for_each_option(&h
[1], oend
, otype
, olen
, d
) {
726 if (otype
== DHCPV6_OPT_IA_PREFIX
&& (olen
+ 4) >=
727 (uint16_t)sizeof(struct dhcpv6_ia_prefix
)) {
728 struct dhcpv6_ia_prefix
*p
= (struct dhcpv6_ia_prefix
*)&d
[-4];
732 } else if (otype
== DHCPV6_OPT_IA_NA
) {
733 struct dhcpv6_ia_hdr
*h
= (struct dhcpv6_ia_hdr
*)&odata
[-4];
734 uint8_t *oend
= odata
+ olen
, *d
;
735 dhcpv6_for_each_option(&h
[1], oend
, otype
, olen
, d
)
736 if (otype
== DHCPV6_OPT_IA_ADDR
)
741 if ((!have_na
&& na_mode
== IA_MODE_FORCE
) ||
742 (!have_pd
&& pd_mode
== IA_MODE_FORCE
))
745 if (na_mode
!= IA_MODE_NONE
&& !have_na
) {
746 cand
.has_noaddravail
= true;
747 cand
.preference
-= 1000;
750 if (pd_mode
!= IA_MODE_NONE
) {
752 cand
.preference
+= 2000 + (128 - have_pd
);
754 cand
.preference
-= 2000;
757 if (cand
.duid_len
> 0) {
758 cand
.ia_na
= odhcp6c_move_state(STATE_IA_NA
, &cand
.ia_na_len
);
759 cand
.ia_pd
= odhcp6c_move_state(STATE_IA_PD
, &cand
.ia_pd_len
);
760 dhcpv6_add_server_cand(&cand
);
763 return (rc
> 1 || (pref
== 255 && cand
.preference
> 0)) ? 1 : -1;
767 static int dhcpv6_commit_advert(void)
769 return dhcpv6_promote_server_cand();
773 static int dhcpv6_handle_rebind_reply(enum dhcpv6_msg orig
, const int rc
,
774 const void *opt
, const void *end
)
776 dhcpv6_handle_advert(orig
, rc
, opt
, end
);
777 if (dhcpv6_commit_advert() < 0)
780 return dhcpv6_handle_reply(orig
, rc
, opt
, end
);
784 static int dhcpv6_handle_reply(enum dhcpv6_msg orig
, _unused
const int rc
,
785 const void *opt
, const void *end
)
788 uint16_t otype
, olen
;
789 uint32_t refresh
= UINT32_MAX
;
791 bool handled_status_codes
[_DHCPV6_Status_Max
] = { false, };
795 if (orig
== DHCPV6_MSG_UNKNOWN
) {
796 static time_t last_update
= 0;
797 time_t now
= odhcp6c_get_milli_time() / 1000;
799 uint32_t elapsed
= (last_update
> 0) ? now
- last_update
: 0;
816 if (orig
== DHCPV6_MSG_REQUEST
&& !odhcp6c_is_bound()) {
817 // Delete NA and PD we have in the state from the Advert
818 odhcp6c_clear_state(STATE_IA_NA
);
819 odhcp6c_clear_state(STATE_IA_PD
);
823 odhcp6c_clear_state(STATE_DNS
);
824 odhcp6c_clear_state(STATE_SEARCH
);
825 odhcp6c_clear_state(STATE_SNTP_IP
);
826 odhcp6c_clear_state(STATE_SNTP_FQDN
);
827 odhcp6c_clear_state(STATE_SIP_IP
);
828 odhcp6c_clear_state(STATE_SIP_FQDN
);
829 odhcp6c_clear_state(STATE_AFTR_NAME
);
832 // Parse and find all matching IAs
833 dhcpv6_for_each_option(opt
, end
, otype
, olen
, odata
) {
834 if ((otype
== DHCPV6_OPT_IA_PD
|| otype
== DHCPV6_OPT_IA_NA
)
835 && olen
> sizeof(struct dhcpv6_ia_hdr
)) {
836 struct dhcpv6_ia_hdr
*ia_hdr
= (void*)(&odata
[-4]);
839 if (ia_hdr
->iaid
!= 1)
842 uint16_t code
= DHCPV6_Success
;
843 uint16_t stype
, slen
;
845 // Get and handle status code
846 dhcpv6_for_each_option(&ia_hdr
[1], odata
+ olen
,
847 stype
, slen
, sdata
) {
848 if (stype
== DHCPV6_OPT_STATUS
&& slen
>= 2) {
849 uint8_t *mdata
= (slen
> 2) ? &sdata
[2] : NULL
;
850 uint16_t mlen
= (slen
> 2) ? slen
- 2 : 0;
852 code
= ((int)sdata
[0]) << 8 | ((int)sdata
[1]);
854 if (code
== DHCPV6_Success
)
857 dhcpv6_handle_ia_status_code(orig
, ia_hdr
,
858 code
, mdata
, mlen
, handled_status_codes
, &ret
);
867 if (code
!= DHCPV6_Success
)
870 dhcpv6_parse_ia(ia_hdr
, odata
+ olen
+ sizeof(*ia_hdr
));
871 } else if (otype
== DHCPV6_OPT_UNICAST
&& olen
== sizeof(server_addr
)) {
872 server_addr
= *(struct in6_addr
*)odata
;
873 } else if (otype
== DHCPV6_OPT_STATUS
&& olen
>= 2) {
874 uint8_t *mdata
= (olen
> 2) ? &odata
[2] : NULL
;
875 uint16_t mlen
= (olen
> 2) ? olen
- 2 : 0;
876 uint16_t code
= ((int)odata
[0]) << 8 | ((int)odata
[1]);
878 dhcpv6_handle_status_code(orig
, code
, mdata
, mlen
, &ret
);
880 else if (otype
== DHCPV6_OPT_DNS_SERVERS
) {
882 odhcp6c_add_state(STATE_DNS
, odata
, olen
);
883 } else if (otype
== DHCPV6_OPT_DNS_DOMAIN
) {
884 odhcp6c_add_state(STATE_SEARCH
, odata
, olen
);
885 } else if (otype
== DHCPV6_OPT_NTP_SERVER
) {
886 uint16_t stype
, slen
;
888 // Test status and bail if error
889 dhcpv6_for_each_option(odata
, odata
+ olen
,
890 stype
, slen
, sdata
) {
891 if (slen
== 16 && (stype
== NTP_MC_ADDR
||
892 stype
== NTP_SRV_ADDR
))
893 odhcp6c_add_state(STATE_SNTP_IP
,
895 else if (slen
> 0 && stype
== NTP_SRV_FQDN
)
896 odhcp6c_add_state(STATE_SNTP_FQDN
,
899 } else if (otype
== DHCPV6_OPT_SIP_SERVER_A
) {
901 odhcp6c_add_state(STATE_SIP_IP
, odata
, olen
);
902 } else if (otype
== DHCPV6_OPT_SIP_SERVER_D
) {
903 odhcp6c_add_state(STATE_SIP_FQDN
, odata
, olen
);
904 } else if (otype
== DHCPV6_OPT_INFO_REFRESH
&& olen
>= 4) {
905 refresh
= ntohl(*((uint32_t*)odata
));
906 } else if (otype
== DHCPV6_OPT_AUTH
&& olen
== -4 +
907 sizeof(struct dhcpv6_auth_reconfigure
)) {
908 struct dhcpv6_auth_reconfigure
*r
= (void*)&odata
[-4];
909 if (r
->protocol
== 3 && r
->algorithm
== 1 &&
911 memcpy(reconf_key
, r
->key
, sizeof(r
->key
));
912 } else if (otype
== DHCPV6_OPT_AFTR_NAME
&& olen
> 3) {
914 odhcp6c_get_state(STATE_AFTR_NAME
, &cur_len
);
916 odhcp6c_add_state(STATE_AFTR_NAME
, odata
, olen
);
917 } else if (otype
!= DHCPV6_OPT_CLIENTID
&&
918 otype
!= DHCPV6_OPT_SERVERID
) {
919 odhcp6c_add_state(STATE_CUSTOM_OPTS
,
920 &odata
[-4], olen
+ 4);
924 if (orig
!= DHCPV6_MSG_INFO_REQ
) {
925 // Update refresh timers if no fatal status code was received
926 if ((ret
> 0) && dhcpv6_calc_refresh_timers()) {
928 case DHCPV6_MSG_RENEW
:
929 // Send further renews if T1 is not set
933 case DHCPV6_MSG_REBIND
:
934 // Send further rebinds if T1 and T2 is not set
939 case DHCPV6_MSG_REQUEST
:
940 // All server candidates can be cleared if not yet bound
941 if (!odhcp6c_is_bound())
942 dhcpv6_clear_all_server_cand();
950 // All server candidates can be cleared if not yet bound
951 if (!odhcp6c_is_bound())
952 dhcpv6_clear_all_server_cand();
961 static int dhcpv6_parse_ia(void *opt
, void *end
)
963 struct dhcpv6_ia_hdr
*ia_hdr
= (struct dhcpv6_ia_hdr
*)opt
;
966 uint16_t otype
, olen
;
969 t1
= ntohl(ia_hdr
->t1
);
970 t2
= ntohl(ia_hdr
->t2
);
976 dhcpv6_for_each_option(&ia_hdr
[1], end
, otype
, olen
, odata
) {
977 struct odhcp6c_entry entry
= {IN6ADDR_ANY_INIT
, 0, 0,
978 IN6ADDR_ANY_INIT
, 0, 0, 0, 0, 0};
980 if (otype
== DHCPV6_OPT_IA_PREFIX
) {
981 struct dhcpv6_ia_prefix
*prefix
= (void*)&odata
[-4];
982 if (olen
+ 4U < sizeof(*prefix
))
985 entry
.valid
= ntohl(prefix
->valid
);
986 entry
.preferred
= ntohl(prefix
->preferred
);
988 if (entry
.preferred
> entry
.valid
)
991 entry
.t1
= (t1
? t1
: (entry
.preferred
!= UINT32_MAX
? 0.5 * entry
.preferred
: UINT32_MAX
));
992 entry
.t2
= (t2
? t2
: (entry
.preferred
!= UINT32_MAX
? 0.8 * entry
.preferred
: UINT32_MAX
));
993 if (entry
.t1
> entry
.t2
)
996 entry
.length
= prefix
->prefix
;
997 entry
.target
= prefix
->addr
;
998 uint16_t stype
, slen
;
1001 #ifdef EXT_PREFIX_CLASS
1002 // Find prefix class, if any
1003 dhcpv6_for_each_option(&prefix
[1], odata
+ olen
,
1005 if (stype
== DHCPV6_OPT_PREFIX_CLASS
&& slen
== 2)
1006 entry
.class = sdata
[0] << 8 | sdata
[1];
1011 dhcpv6_for_each_option(odata
+ sizeof(*prefix
) - 4U,
1012 odata
+ olen
, stype
, slen
, sdata
) {
1013 if (stype
!= DHCPV6_OPT_PD_EXCLUDE
|| slen
< 2)
1016 uint8_t elen
= sdata
[0];
1020 if (elen
<= 32 || elen
<= entry
.length
) {
1026 uint8_t bytes
= ((elen
- entry
.length
- 1) / 8) + 1;
1027 if (slen
<= bytes
) {
1032 uint32_t exclude
= 0;
1034 exclude
= exclude
<< 8 | sdata
[bytes
];
1037 exclude
>>= 8 - ((elen
- entry
.length
) % 8);
1038 exclude
<<= 64 - elen
;
1040 // Abusing router & priority fields for exclusion
1041 entry
.router
= entry
.target
;
1042 entry
.router
.s6_addr32
[1] |= htonl(exclude
);
1043 entry
.priority
= elen
;
1047 odhcp6c_update_entry(STATE_IA_PD
, &entry
);
1052 memset(&entry
.router
, 0, sizeof(entry
.router
));
1053 } else if (otype
== DHCPV6_OPT_IA_ADDR
) {
1054 struct dhcpv6_ia_addr
*addr
= (void*)&odata
[-4];
1055 if (olen
+ 4U < sizeof(*addr
))
1058 entry
.preferred
= ntohl(addr
->preferred
);
1059 entry
.valid
= ntohl(addr
->valid
);
1061 if (entry
.preferred
> entry
.valid
)
1064 entry
.t1
= (t1
? t1
: (entry
.preferred
!= UINT32_MAX
? 0.5 * entry
.preferred
: UINT32_MAX
));
1065 entry
.t2
= (t2
? t2
: (entry
.preferred
!= UINT32_MAX
? 0.8 * entry
.preferred
: UINT32_MAX
));
1066 if (entry
.t1
> entry
.t2
)
1067 entry
.t1
= entry
.t2
;
1070 entry
.target
= addr
->addr
;
1072 #ifdef EXT_PREFIX_CLASS
1073 uint16_t stype
, slen
;
1075 // Find prefix class, if any
1076 dhcpv6_for_each_option(&addr
[1], odata
+ olen
,
1078 if (stype
== DHCPV6_OPT_PREFIX_CLASS
&& slen
== 2)
1079 entry
.class = sdata
[0] << 8 | sdata
[1];
1082 odhcp6c_update_entry(STATE_IA_NA
, &entry
);
1090 static int dhcpv6_calc_refresh_timers(void)
1092 struct odhcp6c_entry
*e
;
1093 size_t ia_na_entries
, ia_pd_entries
, i
;
1094 int64_t l_t1
= UINT32_MAX
, l_t2
= UINT32_MAX
, l_t3
= 0;
1096 e
= odhcp6c_get_state(STATE_IA_NA
, &ia_na_entries
);
1097 ia_na_entries
/= sizeof(*e
);
1098 for (i
= 0; i
< ia_na_entries
; i
++) {
1105 if (e
[i
].valid
> l_t3
)
1109 e
= odhcp6c_get_state(STATE_IA_PD
, &ia_pd_entries
);
1110 ia_pd_entries
/= sizeof(*e
);
1111 for (i
= 0; i
< ia_pd_entries
; i
++) {
1118 if (e
[i
].valid
> l_t3
)
1122 if (ia_pd_entries
|| ia_na_entries
) {
1128 return (int)(ia_pd_entries
+ ia_na_entries
);
1132 static void dhcpv6_log_status_code(const uint16_t code
, const char *scope
,
1133 const void *status_msg
, const int len
)
1135 uint8_t buf
[len
+ 3];
1137 memset(buf
, 0, sizeof(buf
));
1140 memcpy(&buf
[1], status_msg
, len
);
1144 syslog(LOG_WARNING
, "Server returned %s status %i %s",
1149 static void dhcpv6_handle_status_code(const enum dhcpv6_msg orig
,
1150 const uint16_t code
, const void *status_msg
, const int len
,
1153 dhcpv6_log_status_code(code
, "message", status_msg
, len
);
1156 case DHCPV6_UnspecFail
:
1161 case DHCPV6_UseMulticast
:
1163 case DHCPV6_MSG_REQUEST
:
1164 case DHCPV6_MSG_RENEW
:
1165 case DHCPV6_MSG_RELEASE
:
1166 case DHCPV6_MSG_DECLINE
:
1167 // Message needs to be retransmitted according to RFC3315 chapter 18.1.8
1168 server_addr
= in6addr_any
;
1176 case DHCPV6_NoAddrsAvail
:
1177 case DHCPV6_NoPrefixAvail
:
1178 if (orig
== DHCPV6_MSG_REQUEST
)
1179 *ret
= 0; // Failure
1188 static void dhcpv6_handle_ia_status_code(const enum dhcpv6_msg orig
,
1189 const struct dhcpv6_ia_hdr
*ia_hdr
, const uint16_t code
,
1190 const void *status_msg
, const int len
,
1191 bool handled_status_codes
[_DHCPV6_Status_Max
], int *ret
)
1193 dhcpv6_log_status_code(code
, ia_hdr
->type
== DHCPV6_OPT_IA_NA
?
1194 "IA_NA" : "IA_PD", status_msg
, len
);
1197 case DHCPV6_NoBinding
:
1199 case DHCPV6_MSG_RENEW
:
1200 case DHCPV6_MSG_REBIND
:
1201 if ((*ret
> 0) && !handled_status_codes
[code
])
1202 *ret
= dhcpv6_request(DHCPV6_MSG_REQUEST
);
1210 case DHCPV6_NoAddrsAvail
:
1211 case DHCPV6_NoPrefixAvail
:
1213 case DHCPV6_MSG_REQUEST
:
1222 case DHCPV6_NotOnLink
:
1223 // TODO handle not onlink in case of confirm
1231 static void dhcpv6_add_server_cand(const struct dhcpv6_server_cand
*cand
)
1234 struct dhcpv6_server_cand
*c
= odhcp6c_get_state(STATE_SERVER_CAND
, &cand_len
);
1236 // Remove identical duid server candidate
1237 for (i
= 0; i
< cand_len
/ sizeof(*c
); ++i
) {
1238 if (cand
->duid_len
== c
[i
].duid_len
&&
1239 !memcmp(cand
->duid
, c
[i
].duid
, cand
->duid_len
)) {
1242 odhcp6c_remove_state(STATE_SERVER_CAND
, i
* sizeof(*c
), sizeof(*c
));
1247 for (i
= 0, c
= odhcp6c_get_state(STATE_SERVER_CAND
, &cand_len
);
1248 i
< cand_len
/ sizeof(*c
); ++i
) {
1249 if (c
[i
].preference
< cand
->preference
)
1253 odhcp6c_insert_state(STATE_SERVER_CAND
, i
* sizeof(*c
), cand
, sizeof(*cand
));
1256 static void dhcpv6_clear_all_server_cand(void)
1259 struct dhcpv6_server_cand
*c
= odhcp6c_get_state(STATE_SERVER_CAND
, &cand_len
);
1261 // Server candidates need deep delete for IA_NA/IA_PD
1262 for (i
= 0; i
< cand_len
/ sizeof(*c
); ++i
) {
1268 odhcp6c_clear_state(STATE_SERVER_CAND
);
1271 int dhcpv6_promote_server_cand(void)
1274 struct dhcpv6_server_cand
*cand
= odhcp6c_get_state(STATE_SERVER_CAND
, &cand_len
);
1276 int ret
= DHCPV6_STATELESS
;
1278 // Clear lingering candidate state info
1279 odhcp6c_clear_state(STATE_SERVER_ID
);
1280 odhcp6c_clear_state(STATE_IA_NA
);
1281 odhcp6c_clear_state(STATE_IA_PD
);
1286 if (cand
->has_noaddravail
&& na_mode
== IA_MODE_TRY
) {
1287 na_mode
= IA_MODE_NONE
;
1288 return dhcpv6_request(DHCPV6_MSG_SOLICIT
);
1291 hdr
[0] = htons(DHCPV6_OPT_SERVERID
);
1292 hdr
[1] = htons(cand
->duid_len
);
1293 odhcp6c_add_state(STATE_SERVER_ID
, hdr
, sizeof(hdr
));
1294 odhcp6c_add_state(STATE_SERVER_ID
, cand
->duid
, cand
->duid_len
);
1295 accept_reconfig
= cand
->wants_reconfigure
;
1296 if (cand
->ia_na_len
) {
1297 odhcp6c_add_state(STATE_IA_NA
, cand
->ia_na
, cand
->ia_na_len
);
1299 if (na_mode
!= IA_MODE_NONE
)
1300 ret
= DHCPV6_STATEFUL
;
1302 if (cand
->ia_pd_len
) {
1303 odhcp6c_add_state(STATE_IA_PD
, cand
->ia_pd
, cand
->ia_pd_len
);
1306 ret
= DHCPV6_STATEFUL
;
1309 odhcp6c_remove_state(STATE_SERVER_CAND
, 0, sizeof(*cand
));