2 * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
3 * Copyright (C) 2018 Hans Dedecker <dedeckeh@gmail.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License v2 as published by
7 * the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
24 #include <arpa/inet.h>
25 #include <net/route.h>
27 #include <libubox/utils.h>
33 static void forward_router_solicitation(const struct interface
*iface
);
34 static void forward_router_advertisement(const struct interface
*iface
, uint8_t *data
, size_t len
);
36 static void handle_icmpv6(void *addr
, void *data
, size_t len
,
37 struct interface
*iface
, void *dest
);
38 static void trigger_router_advert(struct uloop_timeout
*event
);
39 static void router_netevent_cb(unsigned long event
, struct netevent_handler_info
*info
);
41 static struct odhcpd_event router_event
= {.uloop
= {.fd
= -1}, .handle_dgram
= handle_icmpv6
, };
42 static struct netevent_handler router_netevent_handler
= { .cb
= router_netevent_cb
, };
44 static FILE *fp_route
= NULL
;
47 #define TIME_LEFT(t1, now) ((t1) != UINT32_MAX ? (t1) - (now) : UINT32_MAX)
51 struct icmp6_filter filt
;
54 /* Open ICMPv6 socket */
55 router_event
.uloop
.fd
= socket(AF_INET6
, SOCK_RAW
| SOCK_CLOEXEC
, IPPROTO_ICMPV6
);
56 if (router_event
.uloop
.fd
< 0) {
57 syslog(LOG_ERR
, "socket(AF_INET6): %m");
62 /* Let the kernel compute our checksums */
64 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_RAW
, IPV6_CHECKSUM
,
65 &val
, sizeof(val
)) < 0) {
66 syslog(LOG_ERR
, "setsockopt(IPV6_CHECKSUM): %m");
71 /* This is required by RFC 4861 */
73 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_MULTICAST_HOPS
,
74 &val
, sizeof(val
)) < 0) {
75 syslog(LOG_ERR
, "setsockopt(IPV6_MULTICAST_HOPS): %m");
80 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_UNICAST_HOPS
,
81 &val
, sizeof(val
)) < 0) {
82 syslog(LOG_ERR
, "setsockopt(IPV6_UNICAST_HOPS): %m");
87 /* We need to know the source interface */
89 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_RECVPKTINFO
,
90 &val
, sizeof(val
)) < 0) {
91 syslog(LOG_ERR
, "setsockopt(IPV6_RECVPKTINFO): %m");
96 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_RECVHOPLIMIT
,
97 &val
, sizeof(val
)) < 0) {
98 syslog(LOG_ERR
, "setsockopt(IPV6_RECVHOPLIMIT): %m");
103 /* Don't loop back */
105 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_MULTICAST_LOOP
,
106 &val
, sizeof(val
)) < 0) {
107 syslog(LOG_ERR
, "setsockopt(IPV6_MULTICAST_LOOP): %m");
112 /* Filter ICMPv6 package types */
113 ICMP6_FILTER_SETBLOCKALL(&filt
);
114 ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT
, &filt
);
115 ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT
, &filt
);
116 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_ICMPV6
, ICMP6_FILTER
,
117 &filt
, sizeof(filt
)) < 0) {
118 syslog(LOG_ERR
, "setsockopt(ICMP6_FILTER): %m");
123 if (!(fp_route
= fopen("/proc/net/ipv6_route", "r"))) {
124 syslog(LOG_ERR
, "fopen(/proc/net/ipv6_route): %m");
129 if (netlink_add_netevent_handler(&router_netevent_handler
) < 0) {
130 syslog(LOG_ERR
, "Failed to add netevent handler");
135 /* Register socket */
136 odhcpd_register(&router_event
);
139 if (router_event
.uloop
.fd
> 0) {
140 close(router_event
.uloop
.fd
);
141 router_event
.uloop
.fd
= -1;
154 int router_setup_interface(struct interface
*iface
, bool enable
)
156 struct ipv6_mreq mreq
;
159 if (!fp_route
|| router_event
.uloop
.fd
< 0) {
164 uloop_timeout_cancel(&iface
->timer_rs
);
165 iface
->timer_rs
.cb
= NULL
;
167 memset(&mreq
, 0, sizeof(mreq
));
168 mreq
.ipv6mr_interface
= iface
->ifindex
;
169 inet_pton(AF_INET6
, ALL_IPV6_NODES
, &mreq
.ipv6mr_multiaddr
);
170 setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_DROP_MEMBERSHIP
,
171 &mreq
, sizeof(mreq
));
173 inet_pton(AF_INET6
, ALL_IPV6_ROUTERS
, &mreq
.ipv6mr_multiaddr
);
174 setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
, IPV6_DROP_MEMBERSHIP
,
175 &mreq
, sizeof(mreq
));
178 if (iface
->ra
== MODE_SERVER
|| (iface
->ra
== MODE_RELAY
&& !iface
->master
))
179 trigger_router_advert(&iface
->timer_rs
);
181 if (iface
->ra
== MODE_RELAY
&& iface
->master
) {
182 inet_pton(AF_INET6
, ALL_IPV6_NODES
, &mreq
.ipv6mr_multiaddr
);
183 forward_router_solicitation(iface
);
184 } else if (iface
->ra
== MODE_SERVER
&& !iface
->master
) {
185 iface
->timer_rs
.cb
= trigger_router_advert
;
186 uloop_timeout_set(&iface
->timer_rs
, 1000);
189 if (iface
->ra
== MODE_RELAY
|| (iface
->ra
== MODE_SERVER
&& !iface
->master
)) {
190 if (setsockopt(router_event
.uloop
.fd
, IPPROTO_IPV6
,
191 IPV6_ADD_MEMBERSHIP
, &mreq
, sizeof(mreq
)) < 0) {
193 syslog(LOG_ERR
, "setsockopt(IPV6_ADD_MEMBERSHIP): %m");
202 static void router_netevent_cb(unsigned long event
, struct netevent_handler_info
*info
)
204 struct interface
*iface
;
207 case NETEV_ROUTE6_ADD
:
208 case NETEV_ROUTE6_DEL
:
209 if (info
->rt
.dst_len
)
212 list_for_each_entry(iface
, &interfaces
, head
) {
213 if (iface
->ra
== MODE_SERVER
&& !iface
->master
)
214 uloop_timeout_set(&iface
->timer_rs
, 1000);
217 case NETEV_ADDR6LIST_CHANGE
:
219 if (iface
&& iface
->ra
== MODE_SERVER
&& !iface
->master
)
220 uloop_timeout_set(&iface
->timer_rs
, 1000);
228 static bool router_icmpv6_valid(struct sockaddr_in6
*source
, uint8_t *data
, size_t len
)
230 struct icmp6_hdr
*hdr
= (struct icmp6_hdr
*)data
;
231 struct icmpv6_opt
*opt
, *end
= (struct icmpv6_opt
*)&data
[len
];
233 /* Hoplimit is already checked in odhcpd_receive_packets */
234 if (len
< sizeof(*hdr
) || hdr
->icmp6_code
)
237 switch (hdr
->icmp6_type
) {
238 case ND_ROUTER_ADVERT
:
239 if (!IN6_IS_ADDR_LINKLOCAL(&source
->sin6_addr
))
242 opt
= (struct icmpv6_opt
*)((struct nd_router_advert
*)data
+ 1);
245 case ND_ROUTER_SOLICIT
:
246 opt
= (struct icmpv6_opt
*)((struct nd_router_solicit
*)data
+ 1);
253 icmpv6_for_each_option(opt
, opt
, end
)
254 if (opt
->type
== ND_OPT_SOURCE_LINKADDR
&&
255 IN6_IS_ADDR_UNSPECIFIED(&source
->sin6_addr
) &&
256 hdr
->icmp6_type
== ND_ROUTER_SOLICIT
)
259 /* Check all options parsed successfully */
264 /* Detect whether a default route exists, also find the source prefixes */
265 static bool parse_routes(struct odhcpd_ipaddr
*n
, ssize_t len
)
269 char line
[512], ifname
[16];
270 bool found_default
= false;
271 struct odhcpd_ipaddr p
= { .addr
.in6
= IN6ADDR_ANY_INIT
, .prefix
= 0,
272 .dprefix
= 0, .preferred
= 0, .valid
= 0};
274 while (fgets(line
, sizeof(line
), fp_route
)) {
276 if (sscanf(line
, "00000000000000000000000000000000 00 "
277 "%*s %*s %*s %*s %*s %*s %*s %15s", ifname
) &&
278 strcmp(ifname
, "lo")) {
279 found_default
= true;
280 } else if (sscanf(line
, "%8" SCNx32
"%8" SCNx32
"%*8" SCNx32
"%*8" SCNx32
" %hhx %*s "
281 "%*s 00000000000000000000000000000000 %*s %*s %*s %" SCNx32
" lo",
282 &p
.addr
.in6
.s6_addr32
[0], &p
.addr
.in6
.s6_addr32
[1], &p
.prefix
, &rflags
) &&
283 p
.prefix
> 0 && (rflags
& RTF_NONEXTHOP
) && (rflags
& RTF_REJECT
)) {
284 // Find source prefixes by scanning through unreachable-routes
285 p
.addr
.in6
.s6_addr32
[0] = htonl(p
.addr
.in6
.s6_addr32
[0]);
286 p
.addr
.in6
.s6_addr32
[1] = htonl(p
.addr
.in6
.s6_addr32
[1]);
288 for (ssize_t i
= 0; i
< len
; ++i
) {
289 if (n
[i
].prefix
<= 64 && n
[i
].prefix
>= p
.prefix
&&
290 !odhcpd_bmemcmp(&p
.addr
.in6
, &n
[i
].addr
.in6
, p
.prefix
)) {
291 n
[i
].dprefix
= p
.prefix
;
299 return found_default
;
302 static int calc_adv_interval(struct interface
*iface
, uint32_t minvalid
,
305 uint32_t minival
= iface
->ra_mininterval
;
308 *maxival
= iface
->ra_maxinterval
;
310 if (*maxival
> minvalid
/3)
311 *maxival
= minvalid
/3;
313 if (*maxival
> MaxRtrAdvInterval
)
314 *maxival
= MaxRtrAdvInterval
;
315 else if (*maxival
< 4)
318 if (minival
< MinRtrAdvInterval
)
319 minival
= MinRtrAdvInterval
;
320 else if (minival
> (*maxival
* 3)/4)
321 minival
= (*maxival
>= 9 ? *maxival
/3 : *maxival
);
323 odhcpd_urandom(&msecs
, sizeof(msecs
));
324 msecs
= (labs(msecs
) % ((*maxival
!= minival
) ? (*maxival
- minival
)*1000 : 500)) +
330 static uint16_t calc_ra_lifetime(struct interface
*iface
, uint32_t maxival
)
332 uint16_t lifetime
= 3*maxival
;
334 if (iface
->ra_lifetime
>= 0) {
335 lifetime
= iface
->ra_lifetime
;
336 if (lifetime
< maxival
)
338 else if (lifetime
> 9000)
356 /* Router Advert server mode */
357 static uint64_t send_router_advert(struct interface
*iface
, const struct in6_addr
*from
)
359 time_t now
= odhcpd_time();
360 int mtu
= iface
->ra_mtu
;
361 int hlim
= iface
->ra_hoplimit
;
362 char buf
[INET6_ADDRSTRLEN
];
365 mtu
= odhcpd_get_interface_config(iface
->ifname
, "mtu");
371 hlim
= odhcpd_get_interface_config(iface
->ifname
, "hop_limit");
374 struct nd_router_advert h
;
375 struct icmpv6_opt lladdr
;
376 struct nd_opt_mtu mtu
;
378 .h
= {{.icmp6_type
= ND_ROUTER_ADVERT
, .icmp6_code
= 0}, 0, 0},
379 .lladdr
= {ND_OPT_SOURCE_LINKADDR
, 1, {0}},
380 .mtu
= {ND_OPT_MTU
, 1, 0, htonl(mtu
)},
384 adv
.h
.nd_ra_curhoplimit
= hlim
;
387 adv
.h
.nd_ra_flags_reserved
= ND_RA_FLAG_OTHER
;
389 if (iface
->ra_managed
>= RA_MANAGED_MFLAG
)
390 adv
.h
.nd_ra_flags_reserved
|= ND_RA_FLAG_MANAGED
;
393 if (iface
->route_preference
< 0)
394 adv
.h
.nd_ra_flags_reserved
|= ND_RA_PREF_LOW
;
395 else if (iface
->route_preference
> 0)
396 adv
.h
.nd_ra_flags_reserved
|= ND_RA_PREF_HIGH
;
398 adv
.h
.nd_ra_reachable
= htonl(iface
->ra_reachabletime
);
399 adv
.h
.nd_ra_retransmit
= htonl(iface
->ra_retranstime
);
401 odhcpd_get_mac(iface
, adv
.lladdr
.data
);
403 /* If not currently shutting down */
404 struct odhcpd_ipaddr
*addrs
= NULL
;
406 uint32_t minvalid
= UINT32_MAX
;
407 bool default_route
= false;
408 bool valid_prefix
= false;
410 /* If not shutdown */
411 if (iface
->timer_rs
.cb
) {
412 size_t size
= sizeof(*addrs
) * iface
->addr6_len
;
413 addrs
= alloca(size
);
414 memcpy(addrs
, iface
->addr6
, size
);
416 ipcnt
= iface
->addr6_len
;
418 /* Check default route */
419 if (iface
->default_router
) {
420 default_route
= true;
422 if (iface
->default_router
> 1)
424 } else if (parse_routes(addrs
, ipcnt
))
425 default_route
= true;
428 /* DNS Recursive DNS */
429 struct in6_addr dns_pref
, *dns_addr
= NULL
;
433 if (iface
->dns_cnt
> 0) {
434 dns_addr
= iface
->dns
;
435 dns_cnt
= iface
->dns_cnt
;
436 } else if (!odhcpd_get_interface_dns_addr(iface
, &dns_pref
)) {
437 dns_addr
= &dns_pref
;
442 /* Construct Prefix Information options */
444 struct nd_opt_prefix_info
*pfxs
= NULL
;
446 for (ssize_t i
= 0; i
< ipcnt
; ++i
) {
447 struct odhcpd_ipaddr
*addr
= &addrs
[i
];
448 uint32_t preferred
= 0;
451 if (addr
->prefix
> 96 || addr
->valid
<= (uint32_t)now
) {
452 syslog(LOG_INFO
, "Address %s (prefix %d, valid %u) not suitable as RA prefix on %s",
453 inet_ntop(AF_INET6
, &addr
->addr
.in6
, buf
, sizeof(buf
)), addr
->prefix
,
454 addr
->valid
, iface
->name
);
458 if (odhcpd_bmemcmp(&addr
->addr
, &iface
->pio_filter_addr
,
459 iface
->pio_filter_length
) != 0 ||
460 addr
->prefix
< iface
->pio_filter_length
)
461 continue; // PIO filtered out of this RA
463 struct nd_opt_prefix_info
*p
= NULL
;
464 for (size_t i
= 0; i
< pfxs_cnt
; ++i
) {
465 if (addr
->prefix
== pfxs
[i
].nd_opt_pi_prefix_len
&&
466 !odhcpd_bmemcmp(&pfxs
[i
].nd_opt_pi_prefix
,
467 &addr
->addr
.in6
, addr
->prefix
))
472 struct nd_opt_prefix_info
*tmp
;
474 tmp
= realloc(pfxs
, sizeof(*pfxs
) * (pfxs_cnt
+ 1));
476 syslog(LOG_ERR
, "Realloc failed for RA prefix option on %s", iface
->name
);
481 p
= &pfxs
[pfxs_cnt
++];
482 memset(p
, 0, sizeof(*p
));
485 if (addr
->preferred
> (uint32_t)now
) {
486 preferred
= TIME_LEFT(addr
->preferred
, now
);
488 if (iface
->ra_useleasetime
&&
489 preferred
> iface
->dhcpv4_leasetime
)
490 preferred
= iface
->dhcpv4_leasetime
;
493 valid
= TIME_LEFT(addr
->valid
, now
);
494 if (iface
->ra_useleasetime
&& valid
> iface
->dhcpv4_leasetime
)
495 valid
= iface
->dhcpv4_leasetime
;
497 if (minvalid
> valid
)
500 if (!IN6_IS_ADDR_ULA(&addr
->addr
.in6
) || iface
->default_router
)
503 odhcpd_bmemcpy(&p
->nd_opt_pi_prefix
, &addr
->addr
.in6
,
504 (iface
->ra_advrouter
) ? 128 : addr
->prefix
);
505 p
->nd_opt_pi_type
= ND_OPT_PREFIX_INFORMATION
;
506 p
->nd_opt_pi_len
= 4;
507 p
->nd_opt_pi_prefix_len
= (addr
->prefix
< 64) ? 64 : addr
->prefix
;
508 p
->nd_opt_pi_flags_reserved
= 0;
509 if (!iface
->ra_not_onlink
)
510 p
->nd_opt_pi_flags_reserved
|= ND_OPT_PI_FLAG_ONLINK
;
511 if (iface
->ra_managed
< RA_MANAGED_NO_AFLAG
&& addr
->prefix
<= 64)
512 p
->nd_opt_pi_flags_reserved
|= ND_OPT_PI_FLAG_AUTO
;
513 if (iface
->ra_advrouter
)
514 p
->nd_opt_pi_flags_reserved
|= ND_OPT_PI_FLAG_RADDR
;
515 p
->nd_opt_pi_preferred_time
= htonl(preferred
);
516 p
->nd_opt_pi_valid_time
= htonl(valid
);
519 /* Calculate periodic transmit */
521 int msecs
= calc_adv_interval(iface
, minvalid
, &maxival
);
525 syslog(LOG_WARNING
, "A default route is present but there is no public prefix "
526 "on %s thus we don't announce a default route!", iface
->name
);
527 adv
.h
.nd_ra_router_lifetime
= 0;
529 adv
.h
.nd_ra_router_lifetime
= htons(calc_ra_lifetime(iface
, maxival
));
532 adv
.h
.nd_ra_router_lifetime
= 0;
534 syslog(LOG_INFO
, "Using a RA lifetime of %d seconds on %s", ntohs(adv
.h
.nd_ra_router_lifetime
), iface
->name
);
542 } dns
= {ND_OPT_RECURSIVE_DNS
, (1 + (2 * dns_cnt
)), 0, 0, 0};
544 /* DNS Search options */
545 uint8_t *search_domain
= NULL
;
546 size_t search_len
= 0, search_padded
= 0;
549 search_len
= iface
->search_len
;
550 search_domain
= iface
->search
;
552 if (!search_domain
&& !res_init() && _res
.dnsrch
[0] && _res
.dnsrch
[0][0]) {
553 uint8_t search_buf
[256];
555 int len
= dn_comp(_res
.dnsrch
[0], search_buf
,
556 sizeof(search_buf
), NULL
, NULL
);
558 search_domain
= search_buf
;
565 search_padded
= ((search_len
+ 7) & (~7)) + 8;
574 } *search
= alloca(sizeof(*search
) + search_padded
);
576 search
->type
= ND_OPT_DNS_SEARCH
;
577 search
->len
= search_len
? ((sizeof(*search
) + search_padded
) / 8) : 0;
581 if (search_len
> 0) {
582 memcpy(search
->name
, search_domain
, search_len
);
583 memset(&search
->name
[search_len
], 0, search_padded
- search_len
);
586 size_t routes_cnt
= 0;
594 } *tmp
, *routes
= NULL
;
596 for (ssize_t i
= 0; i
< ipcnt
; ++i
) {
597 struct odhcpd_ipaddr
*addr
= &addrs
[i
];
598 if (addr
->dprefix
> 64 || addr
->dprefix
== 0 || addr
->valid
<= (uint32_t)now
) {
599 syslog(LOG_INFO
, "Address %s (dprefix %d, valid %u) not suitable as RA route on %s",
600 inet_ntop(AF_INET6
, &addr
->addr
.in6
, buf
, sizeof(buf
)),
601 addr
->dprefix
, addr
->valid
, iface
->name
);
603 continue; /* Address not suitable */
606 if (odhcpd_bmemcmp(&addr
->addr
, &iface
->pio_filter_addr
,
607 iface
->pio_filter_length
) != 0 ||
608 addr
->prefix
< iface
->pio_filter_length
)
609 continue; /* RIO filtered out of this RA */
611 if (addr
->dprefix
> 32) {
612 addr
->addr
.in6
.s6_addr32
[1] &= htonl(~((1U << (64 - addr
->dprefix
)) - 1));
613 } else if (addr
->dprefix
<= 32) {
614 addr
->addr
.in6
.s6_addr32
[0] &= htonl(~((1U << (32 - addr
->dprefix
)) - 1));
615 addr
->addr
.in6
.s6_addr32
[1] = 0;
618 tmp
= realloc(routes
, sizeof(*routes
) * (routes_cnt
+ 1));
620 syslog(LOG_ERR
, "Realloc failed for RA route option on %s", iface
->name
);
626 memset(&routes
[routes_cnt
], 0, sizeof(*routes
));
627 routes
[routes_cnt
].type
= ND_OPT_ROUTE_INFO
;
628 routes
[routes_cnt
].len
= sizeof(*routes
) / 8;
629 routes
[routes_cnt
].prefix
= addr
->dprefix
;
630 routes
[routes_cnt
].flags
= 0;
631 if (iface
->route_preference
< 0)
632 routes
[routes_cnt
].flags
|= ND_RA_PREF_LOW
;
633 else if (iface
->route_preference
> 0)
634 routes
[routes_cnt
].flags
|= ND_RA_PREF_HIGH
;
635 routes
[routes_cnt
].lifetime
= htonl(TIME_LEFT(addr
->valid
, now
));
636 routes
[routes_cnt
].addr
[0] = addr
->addr
.in6
.s6_addr32
[0];
637 routes
[routes_cnt
].addr
[1] = addr
->addr
.in6
.s6_addr32
[1];
638 routes
[routes_cnt
].addr
[2] = 0;
639 routes
[routes_cnt
].addr
[3] = 0;
644 search
->lifetime
= htonl(maxival
*10);
645 dns
.lifetime
= search
->lifetime
;
647 struct icmpv6_opt adv_interval
= {
648 .type
= ND_OPT_RTR_ADV_INTERVAL
,
650 .data
= {0, 0, (maxival
*1000) >> 24, (maxival
*1000) >> 16, (maxival
*1000) >> 8, maxival
*1000}
653 struct iovec iov
[IOV_RA_TOTAL
] = {
654 [IOV_RA_ADV
] = {&adv
, sizeof(adv
)},
655 [IOV_RA_PFXS
] = {pfxs
, pfxs_cnt
* sizeof(*pfxs
)},
656 [IOV_RA_ROUTES
] = {routes
, routes_cnt
* sizeof(*routes
)},
657 [IOV_RA_DNS
] = {&dns
, (dns_cnt
) ? sizeof(dns
) : 0},
658 [IOV_RA_DNS_ADDR
] = {dns_addr
, dns_cnt
* sizeof(*dns_addr
)},
659 [IOV_RA_SEARCH
] = {search
, search
->len
* 8},
660 [IOV_RA_ADV_INTERVAL
] = {&adv_interval
, adv_interval
.len
* 8}};
661 struct sockaddr_in6 dest
;
663 memset(&dest
, 0, sizeof(dest
));
664 dest
.sin6_family
= AF_INET6
;
666 if (from
&& !IN6_IS_ADDR_UNSPECIFIED(from
))
667 dest
.sin6_addr
= *from
;
669 inet_pton(AF_INET6
, ALL_IPV6_NODES
, &dest
.sin6_addr
);
671 odhcpd_send(router_event
.uloop
.fd
,
672 &dest
, iov
, ARRAY_SIZE(iov
), iface
);
681 static void trigger_router_advert(struct uloop_timeout
*event
)
683 struct interface
*iface
= container_of(event
, struct interface
, timer_rs
);
684 int msecs
= send_router_advert(iface
, NULL
);
686 /* Rearm timer if not shut down */
688 uloop_timeout_set(event
, msecs
);
692 /* Event handler for incoming ICMPv6 packets */
693 static void handle_icmpv6(void *addr
, void *data
, size_t len
,
694 struct interface
*iface
, _unused
void *dest
)
696 struct icmp6_hdr
*hdr
= data
;
697 struct sockaddr_in6
*from
= addr
;
699 if (!router_icmpv6_valid(addr
, data
, len
))
702 if ((iface
->ra
== MODE_SERVER
&& !iface
->master
)) { /* Server mode */
703 if (hdr
->icmp6_type
== ND_ROUTER_SOLICIT
)
704 send_router_advert(iface
, &from
->sin6_addr
);
705 } else if (iface
->ra
== MODE_RELAY
) { /* Relay mode */
706 if (hdr
->icmp6_type
== ND_ROUTER_ADVERT
&& iface
->master
)
707 forward_router_advertisement(iface
, data
, len
);
708 else if (hdr
->icmp6_type
== ND_ROUTER_SOLICIT
&& !iface
->master
)
709 forward_router_solicitation(odhcpd_get_master_interface());
714 /* Forward router solicitation */
715 static void forward_router_solicitation(const struct interface
*iface
)
717 struct icmp6_hdr rs
= {ND_ROUTER_SOLICIT
, 0, 0, {{0}}};
718 struct iovec iov
= {&rs
, sizeof(rs
)};
719 struct sockaddr_in6 all_routers
;
724 memset(&all_routers
, 0, sizeof(all_routers
));
725 all_routers
.sin6_family
= AF_INET6
;
726 inet_pton(AF_INET6
, ALL_IPV6_ROUTERS
, &all_routers
.sin6_addr
);
727 all_routers
.sin6_scope_id
= iface
->ifindex
;
729 syslog(LOG_NOTICE
, "Sending RS to %s", iface
->name
);
730 odhcpd_send(router_event
.uloop
.fd
, &all_routers
, &iov
, 1, iface
);
734 /* Handler for incoming router solicitations on slave interfaces */
735 static void forward_router_advertisement(const struct interface
*iface
, uint8_t *data
, size_t len
)
737 struct nd_router_advert
*adv
= (struct nd_router_advert
*)data
;
738 struct sockaddr_in6 all_nodes
;
740 /* Rewrite options */
741 uint8_t *end
= data
+ len
;
742 uint8_t *mac_ptr
= NULL
;
743 struct in6_addr
*dns_ptr
= NULL
;
744 size_t dns_count
= 0;
746 struct icmpv6_opt
*opt
;
747 icmpv6_for_each_option(opt
, &adv
[1], end
) {
748 if (opt
->type
== ND_OPT_SOURCE_LINKADDR
) {
749 /* Store address of source MAC-address */
751 } else if (opt
->type
== ND_OPT_RECURSIVE_DNS
&& opt
->len
> 1) {
752 /* Check if we have to rewrite DNS */
753 dns_ptr
= (struct in6_addr
*)&opt
->data
[6];
754 dns_count
= (opt
->len
- 1) / 2;
758 syslog(LOG_NOTICE
, "Got a RA on %s", iface
->name
);
760 /* Indicate a proxy, however we don't follow the rest of RFC 4389 yet */
761 adv
->nd_ra_flags_reserved
|= ND_RA_FLAG_PROXY
;
763 /* Forward advertisement to all slave interfaces */
764 memset(&all_nodes
, 0, sizeof(all_nodes
));
765 all_nodes
.sin6_family
= AF_INET6
;
766 inet_pton(AF_INET6
, ALL_IPV6_NODES
, &all_nodes
.sin6_addr
);
768 struct iovec iov
= {data
, len
};
771 list_for_each_entry(c
, &interfaces
, head
) {
772 if (c
->ra
!= MODE_RELAY
|| c
->master
)
775 /* Fixup source hardware address option */
777 odhcpd_get_mac(c
, mac_ptr
);
779 /* If we have to rewrite DNS entries */
780 if (c
->always_rewrite_dns
&& dns_ptr
&& dns_count
> 0) {
781 const struct in6_addr
*rewrite
= c
->dns
;
782 struct in6_addr addr
;
783 size_t rewrite_cnt
= c
->dns_cnt
;
785 if (rewrite_cnt
== 0) {
786 if (odhcpd_get_interface_dns_addr(c
, &addr
))
787 continue; /* Unable to comply */
793 /* Copy over any other addresses */
794 for (size_t i
= 0; i
< dns_count
; ++i
) {
795 size_t j
= (i
< rewrite_cnt
) ? i
: rewrite_cnt
- 1;
796 dns_ptr
[i
] = rewrite
[j
];
800 odhcpd_send(router_event
.uloop
.fd
, &all_nodes
, &iov
, 1, c
);