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freebsd/sys/netinet6/nd6_rtr.c
Julian Elischer 8b07e49a00 Add code to allow the system to handle multiple routing tables. 
This particular implementation is designed to be fully backwards compatible
and to be MFC-able to 7.x (and 6.x)

Currently the only protocol that can make use of the multiple tables is IPv4
Similar functionality exists in OpenBSD and Linux.

From my notes:

-----

  One thing where FreeBSD has been falling behind, and which by chance I
  have some time to work on is "policy based routing", which allows
  different
  packet streams to be routed by more than just the destination address.

  Constraints:
  ------------

  I want to make some form of this available in the 6.x tree
  (and by extension 7.x) , but FreeBSD in general needs it so I might as
  well do it in -current and back port the portions I need.

  One of the ways that this can be done is to have the ability to
  instantiate multiple kernel routing tables (which I will now
  refer to as "Forwarding Information Bases" or "FIBs" for political
  correctness reasons). Which FIB a particular packet uses to make
  the next hop decision can be decided by a number of mechanisms.
  The policies these mechanisms implement are the "Policies" referred
  to in "Policy based routing".

  One of the constraints I have if I try to back port this work to
  6.x is that it must be implemented as a EXTENSION to the existing
  ABIs in 6.x so that third party applications do not need to be
  recompiled in timespan of the branch.

  This first version will not have some of the bells and whistles that
  will come with later versions. It will, for example, be limited to 16
  tables in the first commit.
  Implementation method, Compatible version. (part 1)
  -------------------------------
  For this reason I have implemented a "sufficient subset" of a
  multiple routing table solution in Perforce, and back-ported it
  to 6.x. (also in Perforce though not  always caught up with what I
  have done in -current/P4). The subset allows a number of FIBs
  to be defined at compile time (8 is sufficient for my purposes in 6.x)
  and implements the changes needed to allow IPV4 to use them. I have not
  done the changes for ipv6 simply because I do not need it, and I do not
  have enough knowledge of ipv6 (e.g. neighbor discovery) needed to do it.

  Other protocol families are left untouched and should there be
  users with proprietary protocol families, they should continue to work
  and be oblivious to the existence of the extra FIBs.

  To understand how this is done, one must know that the current FIB
  code starts everything off with a single dimensional array of
  pointers to FIB head structures (One per protocol family), each of
  which in turn points to the trie of routes available to that family.

  The basic change in the ABI compatible version of the change is to
  extent that array to be a 2 dimensional array, so that
  instead of protocol family X looking at rt_tables[X] for the
  table it needs, it looks at rt_tables[Y][X] when for all
  protocol families except ipv4 Y is always 0.
  Code that is unaware of the change always just sees the first row
  of the table, which of course looks just like the one dimensional
  array that existed before.

  The entry points rtrequest(), rtalloc(), rtalloc1(), rtalloc_ign()
  are all maintained, but refer only to the first row of the array,
  so that existing callers in proprietary protocols can continue to
  do the "right thing".
  Some new entry points are added, for the exclusive use of ipv4 code
  called in_rtrequest(), in_rtalloc(), in_rtalloc1() and in_rtalloc_ign(),
  which have an extra argument which refers the code to the correct row.

  In addition, there are some new entry points (currently called
  rtalloc_fib() and friends) that check the Address family being
  looked up and call either rtalloc() (and friends) if the protocol
  is not IPv4 forcing the action to row 0 or to the appropriate row
  if it IS IPv4 (and that info is available). These are for calling
  from code that is not specific to any particular protocol. The way
  these are implemented would change in the non ABI preserving code
  to be added later.

  One feature of the first version of the code is that for ipv4,
  the interface routes show up automatically on all the FIBs, so
  that no matter what FIB you select you always have the basic
  direct attached hosts available to you. (rtinit() does this
  automatically).

  You CAN delete an interface route from one FIB should you want
  to but by default it's there. ARP information is also available
  in each FIB. It's assumed that the same machine would have the
  same MAC address, regardless of which FIB you are using to get
  to it.

  This brings us as to how the correct FIB is selected for an outgoing
  IPV4 packet.

  Firstly, all packets have a FIB associated with them. if nothing
  has been done to change it, it will be FIB 0. The FIB is changed
  in the following ways.

  Packets fall into one of a number of classes.

  1/ locally generated packets, coming from a socket/PCB.
     Such packets select a FIB from a number associated with the
     socket/PCB. This in turn is inherited from the process,
     but can be changed by a socket option. The process in turn
     inherits it on fork. I have written a utility call setfib
     that acts a bit like nice..

         setfib -3 ping target.example.com # will use fib 3 for ping.

     It is an obvious extension to make it a property of a jail
     but I have not done so. It can be achieved by combining the setfib and
     jail commands.

  2/ packets received on an interface for forwarding.
     By default these packets would use table 0,
     (or possibly a number settable in a sysctl(not yet)).
     but prior to routing the firewall can inspect them (see below).
     (possibly in the future you may be able to associate a FIB
     with packets received on an interface..  An ifconfig arg, but not yet.)

  3/ packets inspected by a packet classifier, which can arbitrarily
     associate a fib with it on a packet by packet basis.
     A fib assigned to a packet by a packet classifier
     (such as ipfw) would over-ride a fib associated by
     a more default source. (such as cases 1 or 2).

  4/ a tcp listen socket associated with a fib will generate
     accept sockets that are associated with that same fib.

  5/ Packets generated in response to some other packet (e.g. reset
     or icmp packets). These should use the FIB associated with the
     packet being reponded to.

  6/ Packets generated during encapsulation.
     gif, tun and other tunnel interfaces will encapsulate using the FIB
     that was in effect withthe proces that set up the tunnel.
     thus setfib 1 ifconfig gif0 [tunnel instructions]
     will set the fib for the tunnel to use to be fib 1.

  Routing messages would be associated with their
  process, and thus select one FIB or another.
  messages from the kernel would be associated with the fib they
  refer to and would only be received by a routing socket associated
  with that fib. (not yet implemented)

  In addition Netstat has been edited to be able to cope with the
  fact that the array is now 2 dimensional. (It looks in system
  memory using libkvm (!)). Old versions of netstat see only the first FIB.

  In addition two sysctls are added to give:
  a) the number of FIBs compiled in (active)
  b) the default FIB of the calling process.

  Early testing experience:
  -------------------------

  Basically our (IronPort's) appliance does this functionality already
  using ipfw fwd but that method has some drawbacks.

  For example,
  It can't fully simulate a routing table because it can't influence the
  socket's choice of local address when a connect() is done.

  Testing during the generating of these changes has been
  remarkably smooth so far. Multiple tables have co-existed
  with no notable side effects, and packets have been routes
  accordingly.

  ipfw has grown 2 new keywords:

  setfib N ip from anay to any
  count ip from any to any fib N

  In pf there seems to be a requirement to be able to give symbolic names to the
  fibs but I do not have that capacity. I am not sure if it is required.

  SCTP has interestingly enough built in support for this, called VRFs
  in Cisco parlance. it will be interesting to see how that handles it
  when it suddenly actually does something.

  Where to next:
  --------------------

  After committing the ABI compatible version and MFCing it, I'd
  like to proceed in a forward direction in -current. this will
  result in some roto-tilling in the routing code.

  Firstly: the current code's idea of having a separate tree per
  protocol family, all of the same format, and pointed to by the
  1 dimensional array is a bit silly. Especially when one considers that
  there is code that makes assumptions about every protocol having the
  same internal structures there. Some protocols don't WANT that
  sort of structure. (for example the whole idea of a netmask is foreign
  to appletalk). This needs to be made opaque to the external code.

  My suggested first change is to add routing method pointers to the
  'domain' structure, along with information pointing the data.
  instead of having an array of pointers to uniform structures,
  there would be an array pointing to the 'domain' structures
  for each protocol address domain (protocol family),
  and the methods this reached would be called. The methods would have
  an argument that gives FIB number, but the protocol would be free
  to ignore it.

  When the ABI can be changed it raises the possibilty of the
  addition of a fib entry into the "struct route". Currently,
  the structure contains the sockaddr of the desination, and the resulting
  fib entry. To make this work fully, one could add a fib number
  so that given an address and a fib, one can find the third element, the
  fib entry.

  Interaction with the ARP layer/ LL layer would need to be
  revisited as well. Qing Li has been working on this already.

  This work was sponsored by Ironport Systems/Cisco

Reviewed by:    several including rwatson, bz and mlair (parts each)
Obtained from:  Ironport systems/Cisco
2008-05-09 23:03:00 +00:00

2099 lines
58 KiB
C
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/*-
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the project nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $KAME: nd6_rtr.c,v 1.111 2001/04/27 01:37:15 jinmei Exp $
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <sys/queue.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/radix.h>
#include <netinet/in.h>
#include <netinet6/in6_var.h>
#include <netinet6/in6_ifattach.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>
#include <netinet/icmp6.h>
#include <netinet6/scope6_var.h>
#define SDL(s) ((struct sockaddr_dl *)s)
static int rtpref(struct nd_defrouter *);
static struct nd_defrouter *defrtrlist_update(struct nd_defrouter *);
static int prelist_update __P((struct nd_prefixctl *, struct nd_defrouter *,
struct mbuf *, int));
static struct in6_ifaddr *in6_ifadd(struct nd_prefixctl *, int);
static struct nd_pfxrouter *pfxrtr_lookup __P((struct nd_prefix *,
struct nd_defrouter *));
static void pfxrtr_add(struct nd_prefix *, struct nd_defrouter *);
static void pfxrtr_del(struct nd_pfxrouter *);
static struct nd_pfxrouter *find_pfxlist_reachable_router
(struct nd_prefix *);
static void defrouter_delreq(struct nd_defrouter *);
static void nd6_rtmsg(int, struct rtentry *);
static int in6_init_prefix_ltimes(struct nd_prefix *);
static void in6_init_address_ltimes __P((struct nd_prefix *,
struct in6_addrlifetime *));
static int rt6_deleteroute(struct radix_node *, void *);
extern int nd6_recalc_reachtm_interval;
static struct ifnet *nd6_defifp;
int nd6_defifindex;
int ip6_use_tempaddr = 0;
int ip6_desync_factor;
u_int32_t ip6_temp_preferred_lifetime = DEF_TEMP_PREFERRED_LIFETIME;
u_int32_t ip6_temp_valid_lifetime = DEF_TEMP_VALID_LIFETIME;
/*
* shorter lifetimes for debugging purposes.
int ip6_temp_preferred_lifetime = 800;
static int ip6_temp_valid_lifetime = 1800;
*/
int ip6_temp_regen_advance = TEMPADDR_REGEN_ADVANCE;
/* RTPREF_MEDIUM has to be 0! */
#define RTPREF_HIGH 1
#define RTPREF_MEDIUM 0
#define RTPREF_LOW (-1)
#define RTPREF_RESERVED (-2)
#define RTPREF_INVALID (-3) /* internal */
/*
* Receive Router Solicitation Message - just for routers.
* Router solicitation/advertisement is mostly managed by userland program
* (rtadvd) so here we have no function like nd6_ra_output().
*
* Based on RFC 2461
*/
void
nd6_rs_input(struct mbuf *m, int off, int icmp6len)
{
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct nd_router_solicit *nd_rs;
struct in6_addr saddr6 = ip6->ip6_src;
char *lladdr = NULL;
int lladdrlen = 0;
union nd_opts ndopts;
char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
/* If I'm not a router, ignore it. */
if (ip6_accept_rtadv != 0 || ip6_forwarding != 1)
goto freeit;
/* Sanity checks */
if (ip6->ip6_hlim != 255) {
nd6log((LOG_ERR,
"nd6_rs_input: invalid hlim (%d) from %s to %s on %s\n",
ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
goto bad;
}
/*
* Don't update the neighbor cache, if src = ::.
* This indicates that the src has no IP address assigned yet.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&saddr6))
goto freeit;
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, icmp6len,);
nd_rs = (struct nd_router_solicit *)((caddr_t)ip6 + off);
#else
IP6_EXTHDR_GET(nd_rs, struct nd_router_solicit *, m, off, icmp6len);
if (nd_rs == NULL) {
icmp6stat.icp6s_tooshort++;
return;
}
#endif
icmp6len -= sizeof(*nd_rs);
nd6_option_init(nd_rs + 1, icmp6len, &ndopts);
if (nd6_options(&ndopts) < 0) {
nd6log((LOG_INFO,
"nd6_rs_input: invalid ND option, ignored\n"));
/* nd6_options have incremented stats */
goto freeit;
}
if (ndopts.nd_opts_src_lladdr) {
lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
}
if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log((LOG_INFO,
"nd6_rs_input: lladdrlen mismatch for %s "
"(if %d, RS packet %d)\n",
ip6_sprintf(ip6bufs, &saddr6),
ifp->if_addrlen, lladdrlen - 2));
goto bad;
}
nd6_cache_lladdr(ifp, &saddr6, lladdr, lladdrlen, ND_ROUTER_SOLICIT, 0);
freeit:
m_freem(m);
return;
bad:
icmp6stat.icp6s_badrs++;
m_freem(m);
}
/*
* Receive Router Advertisement Message.
*
* Based on RFC 2461
* TODO: on-link bit on prefix information
* TODO: ND_RA_FLAG_{OTHER,MANAGED} processing
*/
void
nd6_ra_input(struct mbuf *m, int off, int icmp6len)
{
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct nd_ifinfo *ndi = ND_IFINFO(ifp);
struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
struct nd_router_advert *nd_ra;
struct in6_addr saddr6 = ip6->ip6_src;
int mcast = 0;
union nd_opts ndopts;
struct nd_defrouter *dr;
char ip6bufs[INET6_ADDRSTRLEN], ip6bufd[INET6_ADDRSTRLEN];
/*
* We only accept RAs only when
* the system-wide variable allows the acceptance, and
* per-interface variable allows RAs on the receiving interface.
*/
if (ip6_accept_rtadv == 0)
goto freeit;
if (!(ndi->flags & ND6_IFF_ACCEPT_RTADV))
goto freeit;
if (ip6->ip6_hlim != 255) {
nd6log((LOG_ERR,
"nd6_ra_input: invalid hlim (%d) from %s to %s on %s\n",
ip6->ip6_hlim, ip6_sprintf(ip6bufs, &ip6->ip6_src),
ip6_sprintf(ip6bufd, &ip6->ip6_dst), if_name(ifp)));
goto bad;
}
if (!IN6_IS_ADDR_LINKLOCAL(&saddr6)) {
nd6log((LOG_ERR,
"nd6_ra_input: src %s is not link-local\n",
ip6_sprintf(ip6bufs, &saddr6)));
goto bad;
}
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, icmp6len,);
nd_ra = (struct nd_router_advert *)((caddr_t)ip6 + off);
#else
IP6_EXTHDR_GET(nd_ra, struct nd_router_advert *, m, off, icmp6len);
if (nd_ra == NULL) {
icmp6stat.icp6s_tooshort++;
return;
}
#endif
icmp6len -= sizeof(*nd_ra);
nd6_option_init(nd_ra + 1, icmp6len, &ndopts);
if (nd6_options(&ndopts) < 0) {
nd6log((LOG_INFO,
"nd6_ra_input: invalid ND option, ignored\n"));
/* nd6_options have incremented stats */
goto freeit;
}
{
struct nd_defrouter dr0;
u_int32_t advreachable = nd_ra->nd_ra_reachable;
/* remember if this is a multicasted advertisement */
if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst))
mcast = 1;
bzero(&dr0, sizeof(dr0));
dr0.rtaddr = saddr6;
dr0.flags = nd_ra->nd_ra_flags_reserved;
dr0.rtlifetime = ntohs(nd_ra->nd_ra_router_lifetime);
dr0.expire = time_second + dr0.rtlifetime;
dr0.ifp = ifp;
/* unspecified or not? (RFC 2461 6.3.4) */
if (advreachable) {
advreachable = ntohl(advreachable);
if (advreachable <= MAX_REACHABLE_TIME &&
ndi->basereachable != advreachable) {
ndi->basereachable = advreachable;
ndi->reachable = ND_COMPUTE_RTIME(ndi->basereachable);
ndi->recalctm = nd6_recalc_reachtm_interval; /* reset */
}
}
if (nd_ra->nd_ra_retransmit)
ndi->retrans = ntohl(nd_ra->nd_ra_retransmit);
if (nd_ra->nd_ra_curhoplimit)
ndi->chlim = nd_ra->nd_ra_curhoplimit;
dr = defrtrlist_update(&dr0);
}
/*
* prefix
*/
if (ndopts.nd_opts_pi) {
struct nd_opt_hdr *pt;
struct nd_opt_prefix_info *pi = NULL;
struct nd_prefixctl pr;
for (pt = (struct nd_opt_hdr *)ndopts.nd_opts_pi;
pt <= (struct nd_opt_hdr *)ndopts.nd_opts_pi_end;
pt = (struct nd_opt_hdr *)((caddr_t)pt +
(pt->nd_opt_len << 3))) {
if (pt->nd_opt_type != ND_OPT_PREFIX_INFORMATION)
continue;
pi = (struct nd_opt_prefix_info *)pt;
if (pi->nd_opt_pi_len != 4) {
nd6log((LOG_INFO,
"nd6_ra_input: invalid option "
"len %d for prefix information option, "
"ignored\n", pi->nd_opt_pi_len));
continue;
}
if (128 < pi->nd_opt_pi_prefix_len) {
nd6log((LOG_INFO,
"nd6_ra_input: invalid prefix "
"len %d for prefix information option, "
"ignored\n", pi->nd_opt_pi_prefix_len));
continue;
}
if (IN6_IS_ADDR_MULTICAST(&pi->nd_opt_pi_prefix)
|| IN6_IS_ADDR_LINKLOCAL(&pi->nd_opt_pi_prefix)) {
nd6log((LOG_INFO,
"nd6_ra_input: invalid prefix "
"%s, ignored\n",
ip6_sprintf(ip6bufs,
&pi->nd_opt_pi_prefix)));
continue;
}
bzero(&pr, sizeof(pr));
pr.ndpr_prefix.sin6_family = AF_INET6;
pr.ndpr_prefix.sin6_len = sizeof(pr.ndpr_prefix);
pr.ndpr_prefix.sin6_addr = pi->nd_opt_pi_prefix;
pr.ndpr_ifp = (struct ifnet *)m->m_pkthdr.rcvif;
pr.ndpr_raf_onlink = (pi->nd_opt_pi_flags_reserved &
ND_OPT_PI_FLAG_ONLINK) ? 1 : 0;
pr.ndpr_raf_auto = (pi->nd_opt_pi_flags_reserved &
ND_OPT_PI_FLAG_AUTO) ? 1 : 0;
pr.ndpr_plen = pi->nd_opt_pi_prefix_len;
pr.ndpr_vltime = ntohl(pi->nd_opt_pi_valid_time);
pr.ndpr_pltime = ntohl(pi->nd_opt_pi_preferred_time);
(void)prelist_update(&pr, dr, m, mcast);
}
}
/*
* MTU
*/
if (ndopts.nd_opts_mtu && ndopts.nd_opts_mtu->nd_opt_mtu_len == 1) {
u_long mtu;
u_long maxmtu;
mtu = (u_long)ntohl(ndopts.nd_opts_mtu->nd_opt_mtu_mtu);
/* lower bound */
if (mtu < IPV6_MMTU) {
nd6log((LOG_INFO, "nd6_ra_input: bogus mtu option "
"mtu=%lu sent from %s, ignoring\n",
mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src)));
goto skip;
}
/* upper bound */
maxmtu = (ndi->maxmtu && ndi->maxmtu < ifp->if_mtu)
? ndi->maxmtu : ifp->if_mtu;
if (mtu <= maxmtu) {
int change = (ndi->linkmtu != mtu);
ndi->linkmtu = mtu;
if (change) /* in6_maxmtu may change */
in6_setmaxmtu();
} else {
nd6log((LOG_INFO, "nd6_ra_input: bogus mtu "
"mtu=%lu sent from %s; "
"exceeds maxmtu %lu, ignoring\n",
mtu, ip6_sprintf(ip6bufs, &ip6->ip6_src), maxmtu));
}
}
skip:
/*
* Source link layer address
*/
{
char *lladdr = NULL;
int lladdrlen = 0;
if (ndopts.nd_opts_src_lladdr) {
lladdr = (char *)(ndopts.nd_opts_src_lladdr + 1);
lladdrlen = ndopts.nd_opts_src_lladdr->nd_opt_len << 3;
}
if (lladdr && ((ifp->if_addrlen + 2 + 7) & ~7) != lladdrlen) {
nd6log((LOG_INFO,
"nd6_ra_input: lladdrlen mismatch for %s "
"(if %d, RA packet %d)\n", ip6_sprintf(ip6bufs, &saddr6),
ifp->if_addrlen, lladdrlen - 2));
goto bad;
}
nd6_cache_lladdr(ifp, &saddr6, lladdr,
lladdrlen, ND_ROUTER_ADVERT, 0);
/*
* Installing a link-layer address might change the state of the
* router's neighbor cache, which might also affect our on-link
* detection of adveritsed prefixes.
*/
pfxlist_onlink_check();
}
freeit:
m_freem(m);
return;
bad:
icmp6stat.icp6s_badra++;
m_freem(m);
}
/*
* default router list proccessing sub routines
*/
/* tell the change to user processes watching the routing socket. */
static void
nd6_rtmsg(int cmd, struct rtentry *rt)
{
struct rt_addrinfo info;
bzero((caddr_t)&info, sizeof(info));
info.rti_info[RTAX_DST] = rt_key(rt);
info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
info.rti_info[RTAX_NETMASK] = rt_mask(rt);
if (rt->rt_ifp) {
info.rti_info[RTAX_IFP] =
TAILQ_FIRST(&rt->rt_ifp->if_addrlist)->ifa_addr;
info.rti_info[RTAX_IFA] = rt->rt_ifa->ifa_addr;
}
rt_missmsg(cmd, &info, rt->rt_flags, 0);
}
void
defrouter_addreq(struct nd_defrouter *new)
{
struct sockaddr_in6 def, mask, gate;
struct rtentry *newrt = NULL;
int s;
int error;
bzero(&def, sizeof(def));
bzero(&mask, sizeof(mask));
bzero(&gate, sizeof(gate));
def.sin6_len = mask.sin6_len = gate.sin6_len =
sizeof(struct sockaddr_in6);
def.sin6_family = gate.sin6_family = AF_INET6;
gate.sin6_addr = new->rtaddr;
s = splnet();
error = rtrequest(RTM_ADD, (struct sockaddr *)&def,
(struct sockaddr *)&gate, (struct sockaddr *)&mask,
RTF_GATEWAY, &newrt);
if (newrt) {
RT_LOCK(newrt);
nd6_rtmsg(RTM_ADD, newrt); /* tell user process */
RT_REMREF(newrt);
RT_UNLOCK(newrt);
}
if (error == 0)
new->installed = 1;
splx(s);
return;
}
struct nd_defrouter *
defrouter_lookup(struct in6_addr *addr, struct ifnet *ifp)
{
struct nd_defrouter *dr;
for (dr = TAILQ_FIRST(&nd_defrouter); dr;
dr = TAILQ_NEXT(dr, dr_entry)) {
if (dr->ifp == ifp && IN6_ARE_ADDR_EQUAL(addr, &dr->rtaddr))
return (dr);
}
return (NULL); /* search failed */
}
/*
* Remove the default route for a given router.
* This is just a subroutine function for defrouter_select(), and should
* not be called from anywhere else.
*/
static void
defrouter_delreq(struct nd_defrouter *dr)
{
struct sockaddr_in6 def, mask, gate;
struct rtentry *oldrt = NULL;
bzero(&def, sizeof(def));
bzero(&mask, sizeof(mask));
bzero(&gate, sizeof(gate));
def.sin6_len = mask.sin6_len = gate.sin6_len =
sizeof(struct sockaddr_in6);
def.sin6_family = gate.sin6_family = AF_INET6;
gate.sin6_addr = dr->rtaddr;
rtrequest(RTM_DELETE, (struct sockaddr *)&def,
(struct sockaddr *)&gate,
(struct sockaddr *)&mask, RTF_GATEWAY, &oldrt);
if (oldrt) {
nd6_rtmsg(RTM_DELETE, oldrt);
RTFREE(oldrt);
}
dr->installed = 0;
}
/*
* remove all default routes from default router list
*/
void
defrouter_reset(void)
{
struct nd_defrouter *dr;
for (dr = TAILQ_FIRST(&nd_defrouter); dr;
dr = TAILQ_NEXT(dr, dr_entry))
defrouter_delreq(dr);
/*
* XXX should we also nuke any default routers in the kernel, by
* going through them by rtalloc1()?
*/
}
void
defrtrlist_del(struct nd_defrouter *dr)
{
struct nd_defrouter *deldr = NULL;
struct nd_prefix *pr;
/*
* Flush all the routing table entries that use the router
* as a next hop.
*/
if (!ip6_forwarding && ip6_accept_rtadv) /* XXX: better condition? */
rt6_flush(&dr->rtaddr, dr->ifp);
if (dr->installed) {
deldr = dr;
defrouter_delreq(dr);
}
TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
/*
* Also delete all the pointers to the router in each prefix lists.
*/
for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
struct nd_pfxrouter *pfxrtr;
if ((pfxrtr = pfxrtr_lookup(pr, dr)) != NULL)
pfxrtr_del(pfxrtr);
}
pfxlist_onlink_check();
/*
* If the router is the primary one, choose a new one.
* Note that defrouter_select() will remove the current gateway
* from the routing table.
*/
if (deldr)
defrouter_select();
free(dr, M_IP6NDP);
}
/*
* Default Router Selection according to Section 6.3.6 of RFC 2461 and
* draft-ietf-ipngwg-router-selection:
* 1) Routers that are reachable or probably reachable should be preferred.
* If we have more than one (probably) reachable router, prefer ones
* with the highest router preference.
* 2) When no routers on the list are known to be reachable or
* probably reachable, routers SHOULD be selected in a round-robin
* fashion, regardless of router preference values.
* 3) If the Default Router List is empty, assume that all
* destinations are on-link.
*
* We assume nd_defrouter is sorted by router preference value.
* Since the code below covers both with and without router preference cases,
* we do not need to classify the cases by ifdef.
*
* At this moment, we do not try to install more than one default router,
* even when the multipath routing is available, because we're not sure about
* the benefits for stub hosts comparing to the risk of making the code
* complicated and the possibility of introducing bugs.
*/
void
defrouter_select(void)
{
int s = splnet();
struct nd_defrouter *dr, *selected_dr = NULL, *installed_dr = NULL;
struct rtentry *rt = NULL;
struct llinfo_nd6 *ln = NULL;
/*
* This function should be called only when acting as an autoconfigured
* host. Although the remaining part of this function is not effective
* if the node is not an autoconfigured host, we explicitly exclude
* such cases here for safety.
*/
if (ip6_forwarding || !ip6_accept_rtadv) {
nd6log((LOG_WARNING,
"defrouter_select: called unexpectedly (forwarding=%d, "
"accept_rtadv=%d)\n", ip6_forwarding, ip6_accept_rtadv));
splx(s);
return;
}
/*
* Let's handle easy case (3) first:
* If default router list is empty, there's nothing to be done.
*/
if (!TAILQ_FIRST(&nd_defrouter)) {
splx(s);
return;
}
/*
* Search for a (probably) reachable router from the list.
* We just pick up the first reachable one (if any), assuming that
* the ordering rule of the list described in defrtrlist_update().
*/
for (dr = TAILQ_FIRST(&nd_defrouter); dr;
dr = TAILQ_NEXT(dr, dr_entry)) {
if (selected_dr == NULL &&
(rt = nd6_lookup(&dr->rtaddr, 0, dr->ifp)) &&
(ln = (struct llinfo_nd6 *)rt->rt_llinfo) &&
ND6_IS_LLINFO_PROBREACH(ln)) {
selected_dr = dr;
}
if (dr->installed && installed_dr == NULL)
installed_dr = dr;
else if (dr->installed && installed_dr) {
/* this should not happen. warn for diagnosis. */
log(LOG_ERR, "defrouter_select: more than one router"
" is installed\n");
}
}
/*
* If none of the default routers was found to be reachable,
* round-robin the list regardless of preference.
* Otherwise, if we have an installed router, check if the selected
* (reachable) router should really be preferred to the installed one.
* We only prefer the new router when the old one is not reachable
* or when the new one has a really higher preference value.
*/
if (selected_dr == NULL) {
if (installed_dr == NULL || !TAILQ_NEXT(installed_dr, dr_entry))
selected_dr = TAILQ_FIRST(&nd_defrouter);
else
selected_dr = TAILQ_NEXT(installed_dr, dr_entry);
} else if (installed_dr &&
(rt = nd6_lookup(&installed_dr->rtaddr, 0, installed_dr->ifp)) &&
(ln = (struct llinfo_nd6 *)rt->rt_llinfo) &&
ND6_IS_LLINFO_PROBREACH(ln) &&
rtpref(selected_dr) <= rtpref(installed_dr)) {
selected_dr = installed_dr;
}
/*
* If the selected router is different than the installed one,
* remove the installed router and install the selected one.
* Note that the selected router is never NULL here.
*/
if (installed_dr != selected_dr) {
if (installed_dr)
defrouter_delreq(installed_dr);
defrouter_addreq(selected_dr);
}
splx(s);
return;
}
/*
* for default router selection
* regards router-preference field as a 2-bit signed integer
*/
static int
rtpref(struct nd_defrouter *dr)
{
switch (dr->flags & ND_RA_FLAG_RTPREF_MASK) {
case ND_RA_FLAG_RTPREF_HIGH:
return (RTPREF_HIGH);
case ND_RA_FLAG_RTPREF_MEDIUM:
case ND_RA_FLAG_RTPREF_RSV:
return (RTPREF_MEDIUM);
case ND_RA_FLAG_RTPREF_LOW:
return (RTPREF_LOW);
default:
/*
* This case should never happen. If it did, it would mean a
* serious bug of kernel internal. We thus always bark here.
* Or, can we even panic?
*/
log(LOG_ERR, "rtpref: impossible RA flag %x\n", dr->flags);
return (RTPREF_INVALID);
}
/* NOTREACHED */
}
static struct nd_defrouter *
defrtrlist_update(struct nd_defrouter *new)
{
struct nd_defrouter *dr, *n;
int s = splnet();
if ((dr = defrouter_lookup(&new->rtaddr, new->ifp)) != NULL) {
/* entry exists */
if (new->rtlifetime == 0) {
defrtrlist_del(dr);
dr = NULL;
} else {
int oldpref = rtpref(dr);
/* override */
dr->flags = new->flags; /* xxx flag check */
dr->rtlifetime = new->rtlifetime;
dr->expire = new->expire;
/*
* If the preference does not change, there's no need
* to sort the entries.
*/
if (rtpref(new) == oldpref) {
splx(s);
return (dr);
}
/*
* preferred router may be changed, so relocate
* this router.
* XXX: calling TAILQ_REMOVE directly is a bad manner.
* However, since defrtrlist_del() has many side
* effects, we intentionally do so here.
* defrouter_select() below will handle routing
* changes later.
*/
TAILQ_REMOVE(&nd_defrouter, dr, dr_entry);
n = dr;
goto insert;
}
splx(s);
return (dr);
}
/* entry does not exist */
if (new->rtlifetime == 0) {
splx(s);
return (NULL);
}
n = (struct nd_defrouter *)malloc(sizeof(*n), M_IP6NDP, M_NOWAIT);
if (n == NULL) {
splx(s);
return (NULL);
}
bzero(n, sizeof(*n));
*n = *new;
insert:
/*
* Insert the new router in the Default Router List;
* The Default Router List should be in the descending order
* of router-preferece. Routers with the same preference are
* sorted in the arriving time order.
*/
/* insert at the end of the group */
for (dr = TAILQ_FIRST(&nd_defrouter); dr;
dr = TAILQ_NEXT(dr, dr_entry)) {
if (rtpref(n) > rtpref(dr))
break;
}
if (dr)
TAILQ_INSERT_BEFORE(dr, n, dr_entry);
else
TAILQ_INSERT_TAIL(&nd_defrouter, n, dr_entry);
defrouter_select();
splx(s);
return (n);
}
static struct nd_pfxrouter *
pfxrtr_lookup(struct nd_prefix *pr, struct nd_defrouter *dr)
{
struct nd_pfxrouter *search;
for (search = pr->ndpr_advrtrs.lh_first; search; search = search->pfr_next) {
if (search->router == dr)
break;
}
return (search);
}
static void
pfxrtr_add(struct nd_prefix *pr, struct nd_defrouter *dr)
{
struct nd_pfxrouter *new;
new = (struct nd_pfxrouter *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT);
if (new == NULL)
return;
bzero(new, sizeof(*new));
new->router = dr;
LIST_INSERT_HEAD(&pr->ndpr_advrtrs, new, pfr_entry);
pfxlist_onlink_check();
}
static void
pfxrtr_del(struct nd_pfxrouter *pfr)
{
LIST_REMOVE(pfr, pfr_entry);
free(pfr, M_IP6NDP);
}
struct nd_prefix *
nd6_prefix_lookup(struct nd_prefixctl *key)
{
struct nd_prefix *search;
for (search = nd_prefix.lh_first; search; search = search->ndpr_next) {
if (key->ndpr_ifp == search->ndpr_ifp &&
key->ndpr_plen == search->ndpr_plen &&
in6_are_prefix_equal(&key->ndpr_prefix.sin6_addr,
&search->ndpr_prefix.sin6_addr, key->ndpr_plen)) {
break;
}
}
return (search);
}
int
nd6_prelist_add(struct nd_prefixctl *pr, struct nd_defrouter *dr,
struct nd_prefix **newp)
{
struct nd_prefix *new = NULL;
int error = 0;
int i, s;
char ip6buf[INET6_ADDRSTRLEN];
new = (struct nd_prefix *)malloc(sizeof(*new), M_IP6NDP, M_NOWAIT);
if (new == NULL)
return(ENOMEM);
bzero(new, sizeof(*new));
new->ndpr_ifp = pr->ndpr_ifp;
new->ndpr_prefix = pr->ndpr_prefix;
new->ndpr_plen = pr->ndpr_plen;
new->ndpr_vltime = pr->ndpr_vltime;
new->ndpr_pltime = pr->ndpr_pltime;
new->ndpr_flags = pr->ndpr_flags;
if ((error = in6_init_prefix_ltimes(new)) != 0) {
free(new, M_IP6NDP);
return(error);
}
new->ndpr_lastupdate = time_second;
if (newp != NULL)
*newp = new;
/* initialization */
LIST_INIT(&new->ndpr_advrtrs);
in6_prefixlen2mask(&new->ndpr_mask, new->ndpr_plen);
/* make prefix in the canonical form */
for (i = 0; i < 4; i++)
new->ndpr_prefix.sin6_addr.s6_addr32[i] &=
new->ndpr_mask.s6_addr32[i];
s = splnet();
/* link ndpr_entry to nd_prefix list */
LIST_INSERT_HEAD(&nd_prefix, new, ndpr_entry);
splx(s);
/* ND_OPT_PI_FLAG_ONLINK processing */
if (new->ndpr_raf_onlink) {
int e;
if ((e = nd6_prefix_onlink(new)) != 0) {
nd6log((LOG_ERR, "nd6_prelist_add: failed to make "
"the prefix %s/%d on-link on %s (errno=%d)\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
/* proceed anyway. XXX: is it correct? */
}
}
if (dr)
pfxrtr_add(new, dr);
return 0;
}
void
prelist_remove(struct nd_prefix *pr)
{
struct nd_pfxrouter *pfr, *next;
int e, s;
char ip6buf[INET6_ADDRSTRLEN];
/* make sure to invalidate the prefix until it is really freed. */
pr->ndpr_vltime = 0;
pr->ndpr_pltime = 0;
/*
* Though these flags are now meaningless, we'd rather keep the value
* of pr->ndpr_raf_onlink and pr->ndpr_raf_auto not to confuse users
* when executing "ndp -p".
*/
if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0 &&
(e = nd6_prefix_offlink(pr)) != 0) {
nd6log((LOG_ERR, "prelist_remove: failed to make %s/%d offlink "
"on %s, errno=%d\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
/* what should we do? */
}
if (pr->ndpr_refcnt > 0)
return; /* notice here? */
s = splnet();
/* unlink ndpr_entry from nd_prefix list */
LIST_REMOVE(pr, ndpr_entry);
/* free list of routers that adversed the prefix */
for (pfr = pr->ndpr_advrtrs.lh_first; pfr; pfr = next) {
next = pfr->pfr_next;
free(pfr, M_IP6NDP);
}
splx(s);
free(pr, M_IP6NDP);
pfxlist_onlink_check();
}
/*
* dr - may be NULL
*/
static int
prelist_update(struct nd_prefixctl *new, struct nd_defrouter *dr,
struct mbuf *m, int mcast)
{
struct in6_ifaddr *ia6 = NULL, *ia6_match = NULL;
struct ifaddr *ifa;
struct ifnet *ifp = new->ndpr_ifp;
struct nd_prefix *pr;
int s = splnet();
int error = 0;
int newprefix = 0;
int auth;
struct in6_addrlifetime lt6_tmp;
char ip6buf[INET6_ADDRSTRLEN];
auth = 0;
if (m) {
/*
* Authenticity for NA consists authentication for
* both IP header and IP datagrams, doesn't it ?
*/
#if defined(M_AUTHIPHDR) && defined(M_AUTHIPDGM)
auth = ((m->m_flags & M_AUTHIPHDR) &&
(m->m_flags & M_AUTHIPDGM));
#endif
}
if ((pr = nd6_prefix_lookup(new)) != NULL) {
/*
* nd6_prefix_lookup() ensures that pr and new have the same
* prefix on a same interface.
*/
/*
* Update prefix information. Note that the on-link (L) bit
* and the autonomous (A) bit should NOT be changed from 1
* to 0.
*/
if (new->ndpr_raf_onlink == 1)
pr->ndpr_raf_onlink = 1;
if (new->ndpr_raf_auto == 1)
pr->ndpr_raf_auto = 1;
if (new->ndpr_raf_onlink) {
pr->ndpr_vltime = new->ndpr_vltime;
pr->ndpr_pltime = new->ndpr_pltime;
(void)in6_init_prefix_ltimes(pr); /* XXX error case? */
pr->ndpr_lastupdate = time_second;
}
if (new->ndpr_raf_onlink &&
(pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
int e;
if ((e = nd6_prefix_onlink(pr)) != 0) {
nd6log((LOG_ERR,
"prelist_update: failed to make "
"the prefix %s/%d on-link on %s "
"(errno=%d)\n",
ip6_sprintf(ip6buf,
&pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, if_name(pr->ndpr_ifp), e));
/* proceed anyway. XXX: is it correct? */
}
}
if (dr && pfxrtr_lookup(pr, dr) == NULL)
pfxrtr_add(pr, dr);
} else {
struct nd_prefix *newpr = NULL;
newprefix = 1;
if (new->ndpr_vltime == 0)
goto end;
if (new->ndpr_raf_onlink == 0 && new->ndpr_raf_auto == 0)
goto end;
error = nd6_prelist_add(new, dr, &newpr);
if (error != 0 || newpr == NULL) {
nd6log((LOG_NOTICE, "prelist_update: "
"nd6_prelist_add failed for %s/%d on %s "
"errno=%d, returnpr=%p\n",
ip6_sprintf(ip6buf, &new->ndpr_prefix.sin6_addr),
new->ndpr_plen, if_name(new->ndpr_ifp),
error, newpr));
goto end; /* we should just give up in this case. */
}
/*
* XXX: from the ND point of view, we can ignore a prefix
* with the on-link bit being zero. However, we need a
* prefix structure for references from autoconfigured
* addresses. Thus, we explicitly make sure that the prefix
* itself expires now.
*/
if (newpr->ndpr_raf_onlink == 0) {
newpr->ndpr_vltime = 0;
newpr->ndpr_pltime = 0;
in6_init_prefix_ltimes(newpr);
}
pr = newpr;
}
/*
* Address autoconfiguration based on Section 5.5.3 of RFC 2462.
* Note that pr must be non NULL at this point.
*/
/* 5.5.3 (a). Ignore the prefix without the A bit set. */
if (!new->ndpr_raf_auto)
goto end;
/*
* 5.5.3 (b). the link-local prefix should have been ignored in
* nd6_ra_input.
*/
/* 5.5.3 (c). Consistency check on lifetimes: pltime <= vltime. */
if (new->ndpr_pltime > new->ndpr_vltime) {
error = EINVAL; /* XXX: won't be used */
goto end;
}
/*
* 5.5.3 (d). If the prefix advertised is not equal to the prefix of
* an address configured by stateless autoconfiguration already in the
* list of addresses associated with the interface, and the Valid
* Lifetime is not 0, form an address. We first check if we have
* a matching prefix.
* Note: we apply a clarification in rfc2462bis-02 here. We only
* consider autoconfigured addresses while RFC2462 simply said
* "address".
*/
TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
struct in6_ifaddr *ifa6;
u_int32_t remaininglifetime;
if (ifa->ifa_addr->sa_family != AF_INET6)
continue;
ifa6 = (struct in6_ifaddr *)ifa;
/*
* We only consider autoconfigured addresses as per rfc2462bis.
*/
if (!(ifa6->ia6_flags & IN6_IFF_AUTOCONF))
continue;
/*
* Spec is not clear here, but I believe we should concentrate
* on unicast (i.e. not anycast) addresses.
* XXX: other ia6_flags? detached or duplicated?
*/
if ((ifa6->ia6_flags & IN6_IFF_ANYCAST) != 0)
continue;
/*
* Ignore the address if it is not associated with a prefix
* or is associated with a prefix that is different from this
* one. (pr is never NULL here)
*/
if (ifa6->ia6_ndpr != pr)
continue;
if (ia6_match == NULL) /* remember the first one */
ia6_match = ifa6;
/*
* An already autoconfigured address matched. Now that we
* are sure there is at least one matched address, we can
* proceed to 5.5.3. (e): update the lifetimes according to the
* "two hours" rule and the privacy extension.
* We apply some clarifications in rfc2462bis:
* - use remaininglifetime instead of storedlifetime as a
* variable name
* - remove the dead code in the "two-hour" rule
*/
#define TWOHOUR (120*60)
lt6_tmp = ifa6->ia6_lifetime;
if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME)
remaininglifetime = ND6_INFINITE_LIFETIME;
else if (time_second - ifa6->ia6_updatetime >
lt6_tmp.ia6t_vltime) {
/*
* The case of "invalid" address. We should usually
* not see this case.
*/
remaininglifetime = 0;
} else
remaininglifetime = lt6_tmp.ia6t_vltime -
(time_second - ifa6->ia6_updatetime);
/* when not updating, keep the current stored lifetime. */
lt6_tmp.ia6t_vltime = remaininglifetime;
if (TWOHOUR < new->ndpr_vltime ||
remaininglifetime < new->ndpr_vltime) {
lt6_tmp.ia6t_vltime = new->ndpr_vltime;
} else if (remaininglifetime <= TWOHOUR) {
if (auth) {
lt6_tmp.ia6t_vltime = new->ndpr_vltime;
}
} else {
/*
* new->ndpr_vltime <= TWOHOUR &&
* TWOHOUR < remaininglifetime
*/
lt6_tmp.ia6t_vltime = TWOHOUR;
}
/* The 2 hour rule is not imposed for preferred lifetime. */
lt6_tmp.ia6t_pltime = new->ndpr_pltime;
in6_init_address_ltimes(pr, &lt6_tmp);
/*
* We need to treat lifetimes for temporary addresses
* differently, according to
* draft-ietf-ipv6-privacy-addrs-v2-01.txt 3.3 (1);
* we only update the lifetimes when they are in the maximum
* intervals.
*/
if ((ifa6->ia6_flags & IN6_IFF_TEMPORARY) != 0) {
u_int32_t maxvltime, maxpltime;
if (ip6_temp_valid_lifetime >
(u_int32_t)((time_second - ifa6->ia6_createtime) +
ip6_desync_factor)) {
maxvltime = ip6_temp_valid_lifetime -
(time_second - ifa6->ia6_createtime) -
ip6_desync_factor;
} else
maxvltime = 0;
if (ip6_temp_preferred_lifetime >
(u_int32_t)((time_second - ifa6->ia6_createtime) +
ip6_desync_factor)) {
maxpltime = ip6_temp_preferred_lifetime -
(time_second - ifa6->ia6_createtime) -
ip6_desync_factor;
} else
maxpltime = 0;
if (lt6_tmp.ia6t_vltime == ND6_INFINITE_LIFETIME ||
lt6_tmp.ia6t_vltime > maxvltime) {
lt6_tmp.ia6t_vltime = maxvltime;
}
if (lt6_tmp.ia6t_pltime == ND6_INFINITE_LIFETIME ||
lt6_tmp.ia6t_pltime > maxpltime) {
lt6_tmp.ia6t_pltime = maxpltime;
}
}
ifa6->ia6_lifetime = lt6_tmp;
ifa6->ia6_updatetime = time_second;
}
if (ia6_match == NULL && new->ndpr_vltime) {
int ifidlen;
/*
* 5.5.3 (d) (continued)
* No address matched and the valid lifetime is non-zero.
* Create a new address.
*/
/*
* Prefix Length check:
* If the sum of the prefix length and interface identifier
* length does not equal 128 bits, the Prefix Information
* option MUST be ignored. The length of the interface
* identifier is defined in a separate link-type specific
* document.
*/
ifidlen = in6_if2idlen(ifp);
if (ifidlen < 0) {
/* this should not happen, so we always log it. */
log(LOG_ERR, "prelist_update: IFID undefined (%s)\n",
if_name(ifp));
goto end;
}
if (ifidlen + pr->ndpr_plen != 128) {
nd6log((LOG_INFO,
"prelist_update: invalid prefixlen "
"%d for %s, ignored\n",
pr->ndpr_plen, if_name(ifp)));
goto end;
}
if ((ia6 = in6_ifadd(new, mcast)) != NULL) {
/*
* note that we should use pr (not new) for reference.
*/
pr->ndpr_refcnt++;
ia6->ia6_ndpr = pr;
/*
* RFC 3041 3.3 (2).
* When a new public address is created as described
* in RFC2462, also create a new temporary address.
*
* RFC 3041 3.5.
* When an interface connects to a new link, a new
* randomized interface identifier should be generated
* immediately together with a new set of temporary
* addresses. Thus, we specifiy 1 as the 2nd arg of
* in6_tmpifadd().
*/
if (ip6_use_tempaddr) {
int e;
if ((e = in6_tmpifadd(ia6, 1, 1)) != 0) {
nd6log((LOG_NOTICE, "prelist_update: "
"failed to create a temporary "
"address, errno=%d\n",
e));
}
}
/*
* A newly added address might affect the status
* of other addresses, so we check and update it.
* XXX: what if address duplication happens?
*/
pfxlist_onlink_check();
} else {
/* just set an error. do not bark here. */
error = EADDRNOTAVAIL; /* XXX: might be unused. */
}
}
end:
splx(s);
return error;
}
/*
* A supplement function used in the on-link detection below;
* detect if a given prefix has a (probably) reachable advertising router.
* XXX: lengthy function name...
*/
static struct nd_pfxrouter *
find_pfxlist_reachable_router(struct nd_prefix *pr)
{
struct nd_pfxrouter *pfxrtr;
struct rtentry *rt;
struct llinfo_nd6 *ln;
for (pfxrtr = LIST_FIRST(&pr->ndpr_advrtrs); pfxrtr;
pfxrtr = LIST_NEXT(pfxrtr, pfr_entry)) {
if ((rt = nd6_lookup(&pfxrtr->router->rtaddr, 0,
pfxrtr->router->ifp)) &&
(ln = (struct llinfo_nd6 *)rt->rt_llinfo) &&
ND6_IS_LLINFO_PROBREACH(ln))
break; /* found */
}
return (pfxrtr);
}
/*
* Check if each prefix in the prefix list has at least one available router
* that advertised the prefix (a router is "available" if its neighbor cache
* entry is reachable or probably reachable).
* If the check fails, the prefix may be off-link, because, for example,
* we have moved from the network but the lifetime of the prefix has not
* expired yet. So we should not use the prefix if there is another prefix
* that has an available router.
* But, if there is no prefix that has an available router, we still regards
* all the prefixes as on-link. This is because we can't tell if all the
* routers are simply dead or if we really moved from the network and there
* is no router around us.
*/
void
pfxlist_onlink_check()
{
struct nd_prefix *pr;
struct in6_ifaddr *ifa;
struct nd_defrouter *dr;
struct nd_pfxrouter *pfxrtr = NULL;
/*
* Check if there is a prefix that has a reachable advertising
* router.
*/
for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
if (pr->ndpr_raf_onlink && find_pfxlist_reachable_router(pr))
break;
}
/*
* If we have no such prefix, check whether we still have a router
* that does not advertise any prefixes.
*/
if (pr == NULL) {
for (dr = TAILQ_FIRST(&nd_defrouter); dr;
dr = TAILQ_NEXT(dr, dr_entry)) {
struct nd_prefix *pr0;
for (pr0 = nd_prefix.lh_first; pr0;
pr0 = pr0->ndpr_next) {
if ((pfxrtr = pfxrtr_lookup(pr0, dr)) != NULL)
break;
}
if (pfxrtr != NULL)
break;
}
}
if (pr != NULL || (TAILQ_FIRST(&nd_defrouter) && pfxrtr == NULL)) {
/*
* There is at least one prefix that has a reachable router,
* or at least a router which probably does not advertise
* any prefixes. The latter would be the case when we move
* to a new link where we have a router that does not provide
* prefixes and we configure an address by hand.
* Detach prefixes which have no reachable advertising
* router, and attach other prefixes.
*/
for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
/* XXX: a link-local prefix should never be detached */
if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
continue;
/*
* we aren't interested in prefixes without the L bit
* set.
*/
if (pr->ndpr_raf_onlink == 0)
continue;
if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
find_pfxlist_reachable_router(pr) == NULL)
pr->ndpr_stateflags |= NDPRF_DETACHED;
if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
find_pfxlist_reachable_router(pr) != 0)
pr->ndpr_stateflags &= ~NDPRF_DETACHED;
}
} else {
/* there is no prefix that has a reachable router */
for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
continue;
if (pr->ndpr_raf_onlink == 0)
continue;
if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0)
pr->ndpr_stateflags &= ~NDPRF_DETACHED;
}
}
/*
* Remove each interface route associated with a (just) detached
* prefix, and reinstall the interface route for a (just) attached
* prefix. Note that all attempt of reinstallation does not
* necessarily success, when a same prefix is shared among multiple
* interfaces. Such cases will be handled in nd6_prefix_onlink,
* so we don't have to care about them.
*/
for (pr = nd_prefix.lh_first; pr; pr = pr->ndpr_next) {
int e;
char ip6buf[INET6_ADDRSTRLEN];
if (IN6_IS_ADDR_LINKLOCAL(&pr->ndpr_prefix.sin6_addr))
continue;
if (pr->ndpr_raf_onlink == 0)
continue;
if ((pr->ndpr_stateflags & NDPRF_DETACHED) != 0 &&
(pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
if ((e = nd6_prefix_offlink(pr)) != 0) {
nd6log((LOG_ERR,
"pfxlist_onlink_check: failed to "
"make %s/%d offlink, errno=%d\n",
ip6_sprintf(ip6buf,
&pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, e));
}
}
if ((pr->ndpr_stateflags & NDPRF_DETACHED) == 0 &&
(pr->ndpr_stateflags & NDPRF_ONLINK) == 0 &&
pr->ndpr_raf_onlink) {
if ((e = nd6_prefix_onlink(pr)) != 0) {
nd6log((LOG_ERR,
"pfxlist_onlink_check: failed to "
"make %s/%d onlink, errno=%d\n",
ip6_sprintf(ip6buf,
&pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, e));
}
}
}
/*
* Changes on the prefix status might affect address status as well.
* Make sure that all addresses derived from an attached prefix are
* attached, and that all addresses derived from a detached prefix are
* detached. Note, however, that a manually configured address should
* always be attached.
* The precise detection logic is same as the one for prefixes.
*/
for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) {
if (!(ifa->ia6_flags & IN6_IFF_AUTOCONF))
continue;
if (ifa->ia6_ndpr == NULL) {
/*
* This can happen when we first configure the address
* (i.e. the address exists, but the prefix does not).
* XXX: complicated relationships...
*/
continue;
}
if (find_pfxlist_reachable_router(ifa->ia6_ndpr))
break;
}
if (ifa) {
for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) {
if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
continue;
if (ifa->ia6_ndpr == NULL) /* XXX: see above. */
continue;
if (find_pfxlist_reachable_router(ifa->ia6_ndpr)) {
if (ifa->ia6_flags & IN6_IFF_DETACHED) {
ifa->ia6_flags &= ~IN6_IFF_DETACHED;
ifa->ia6_flags |= IN6_IFF_TENTATIVE;
nd6_dad_start((struct ifaddr *)ifa, 0);
}
} else {
ifa->ia6_flags |= IN6_IFF_DETACHED;
}
}
}
else {
for (ifa = in6_ifaddr; ifa; ifa = ifa->ia_next) {
if ((ifa->ia6_flags & IN6_IFF_AUTOCONF) == 0)
continue;
if (ifa->ia6_flags & IN6_IFF_DETACHED) {
ifa->ia6_flags &= ~IN6_IFF_DETACHED;
ifa->ia6_flags |= IN6_IFF_TENTATIVE;
/* Do we need a delay in this case? */
nd6_dad_start((struct ifaddr *)ifa, 0);
}
}
}
}
int
nd6_prefix_onlink(struct nd_prefix *pr)
{
struct ifaddr *ifa;
struct ifnet *ifp = pr->ndpr_ifp;
struct sockaddr_in6 mask6;
struct nd_prefix *opr;
u_long rtflags;
int error = 0;
struct rtentry *rt = NULL;
char ip6buf[INET6_ADDRSTRLEN];
/* sanity check */
if ((pr->ndpr_stateflags & NDPRF_ONLINK) != 0) {
nd6log((LOG_ERR,
"nd6_prefix_onlink: %s/%d is already on-link\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen));
return (EEXIST);
}
/*
* Add the interface route associated with the prefix. Before
* installing the route, check if there's the same prefix on another
* interface, and the prefix has already installed the interface route.
* Although such a configuration is expected to be rare, we explicitly
* allow it.
*/
for (opr = nd_prefix.lh_first; opr; opr = opr->ndpr_next) {
if (opr == pr)
continue;
if ((opr->ndpr_stateflags & NDPRF_ONLINK) == 0)
continue;
if (opr->ndpr_plen == pr->ndpr_plen &&
in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
&opr->ndpr_prefix.sin6_addr, pr->ndpr_plen))
return (0);
}
/*
* We prefer link-local addresses as the associated interface address.
*/
/* search for a link-local addr */
ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp,
IN6_IFF_NOTREADY | IN6_IFF_ANYCAST);
if (ifa == NULL) {
/* XXX: freebsd does not have ifa_ifwithaf */
TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) {
if (ifa->ifa_addr->sa_family == AF_INET6)
break;
}
/* should we care about ia6_flags? */
}
if (ifa == NULL) {
/*
* This can still happen, when, for example, we receive an RA
* containing a prefix with the L bit set and the A bit clear,
* after removing all IPv6 addresses on the receiving
* interface. This should, of course, be rare though.
*/
nd6log((LOG_NOTICE,
"nd6_prefix_onlink: failed to find any ifaddr"
" to add route for a prefix(%s/%d) on %s\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, if_name(ifp)));
return (0);
}
/*
* in6_ifinit() sets nd6_rtrequest to ifa_rtrequest for all ifaddrs.
* ifa->ifa_rtrequest = nd6_rtrequest;
*/
bzero(&mask6, sizeof(mask6));
mask6.sin6_len = sizeof(mask6);
mask6.sin6_addr = pr->ndpr_mask;
rtflags = ifa->ifa_flags | RTF_CLONING | RTF_UP;
if (nd6_need_cache(ifp)) {
/* explicitly set in case ifa_flags does not set the flag. */
rtflags |= RTF_CLONING;
} else {
/*
* explicitly clear the cloning bit in case ifa_flags sets it.
*/
rtflags &= ~RTF_CLONING;
}
error = rtrequest(RTM_ADD, (struct sockaddr *)&pr->ndpr_prefix,
ifa->ifa_addr, (struct sockaddr *)&mask6, rtflags, &rt);
if (error == 0) {
if (rt != NULL) /* this should be non NULL, though */
nd6_rtmsg(RTM_ADD, rt);
pr->ndpr_stateflags |= NDPRF_ONLINK;
} else {
char ip6bufg[INET6_ADDRSTRLEN], ip6bufm[INET6_ADDRSTRLEN];
nd6log((LOG_ERR, "nd6_prefix_onlink: failed to add route for a"
" prefix (%s/%d) on %s, gw=%s, mask=%s, flags=%lx "
"errno = %d\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen, if_name(ifp),
ip6_sprintf(ip6bufg, &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr),
ip6_sprintf(ip6bufm, &mask6.sin6_addr), rtflags, error));
}
if (rt != NULL) {
RT_LOCK(rt);
RT_REMREF(rt);
RT_UNLOCK(rt);
}
return (error);
}
int
nd6_prefix_offlink(struct nd_prefix *pr)
{
int error = 0;
struct ifnet *ifp = pr->ndpr_ifp;
struct nd_prefix *opr;
struct sockaddr_in6 sa6, mask6;
struct rtentry *rt = NULL;
char ip6buf[INET6_ADDRSTRLEN];
/* sanity check */
if ((pr->ndpr_stateflags & NDPRF_ONLINK) == 0) {
nd6log((LOG_ERR,
"nd6_prefix_offlink: %s/%d is already off-link\n",
ip6_sprintf(ip6buf, &pr->ndpr_prefix.sin6_addr),
pr->ndpr_plen));
return (EEXIST);
}
bzero(&sa6, sizeof(sa6));
sa6.sin6_family = AF_INET6;
sa6.sin6_len = sizeof(sa6);
bcopy(&pr->ndpr_prefix.sin6_addr, &sa6.sin6_addr,
sizeof(struct in6_addr));
bzero(&mask6, sizeof(mask6));
mask6.sin6_family = AF_INET6;
mask6.sin6_len = sizeof(sa6);
bcopy(&pr->ndpr_mask, &mask6.sin6_addr, sizeof(struct in6_addr));
error = rtrequest(RTM_DELETE, (struct sockaddr *)&sa6, NULL,
(struct sockaddr *)&mask6, 0, &rt);
if (error == 0) {
pr->ndpr_stateflags &= ~NDPRF_ONLINK;
/* report the route deletion to the routing socket. */
if (rt != NULL)
nd6_rtmsg(RTM_DELETE, rt);
/*
* There might be the same prefix on another interface,
* the prefix which could not be on-link just because we have
* the interface route (see comments in nd6_prefix_onlink).
* If there's one, try to make the prefix on-link on the
* interface.
*/
for (opr = nd_prefix.lh_first; opr; opr = opr->ndpr_next) {
if (opr == pr)
continue;
if ((opr->ndpr_stateflags & NDPRF_ONLINK) != 0)
continue;
/*
* KAME specific: detached prefixes should not be
* on-link.
*/
if ((opr->ndpr_stateflags & NDPRF_DETACHED) != 0)
continue;
if (opr->ndpr_plen == pr->ndpr_plen &&
in6_are_prefix_equal(&pr->ndpr_prefix.sin6_addr,
&opr->ndpr_prefix.sin6_addr, pr->ndpr_plen)) {
int e;
if ((e = nd6_prefix_onlink(opr)) != 0) {
nd6log((LOG_ERR,
"nd6_prefix_offlink: failed to "
"recover a prefix %s/%d from %s "
"to %s (errno = %d)\n",
ip6_sprintf(ip6buf,
&opr->ndpr_prefix.sin6_addr),
opr->ndpr_plen, if_name(ifp),
if_name(opr->ndpr_ifp), e));
}
}
}
} else {
/* XXX: can we still set the NDPRF_ONLINK flag? */
nd6log((LOG_ERR,
"nd6_prefix_offlink: failed to delete route: "
"%s/%d on %s (errno = %d)\n",
ip6_sprintf(ip6buf, &sa6.sin6_addr), pr->ndpr_plen,
if_name(ifp), error));
}
if (rt != NULL) {
RTFREE(rt);
}
return (error);
}
static struct in6_ifaddr *
in6_ifadd(struct nd_prefixctl *pr, int mcast)
{
struct ifnet *ifp = pr->ndpr_ifp;
struct ifaddr *ifa;
struct in6_aliasreq ifra;
struct in6_ifaddr *ia, *ib;
int error, plen0;
struct in6_addr mask;
int prefixlen = pr->ndpr_plen;
int updateflags;
char ip6buf[INET6_ADDRSTRLEN];
in6_prefixlen2mask(&mask, prefixlen);
/*
* find a link-local address (will be interface ID).
* Is it really mandatory? Theoretically, a global or a site-local
* address can be configured without a link-local address, if we
* have a unique interface identifier...
*
* it is not mandatory to have a link-local address, we can generate
* interface identifier on the fly. we do this because:
* (1) it should be the easiest way to find interface identifier.
* (2) RFC2462 5.4 suggesting the use of the same interface identifier
* for multiple addresses on a single interface, and possible shortcut
* of DAD. we omitted DAD for this reason in the past.
* (3) a user can prevent autoconfiguration of global address
* by removing link-local address by hand (this is partly because we
* don't have other way to control the use of IPv6 on an interface.
* this has been our design choice - cf. NRL's "ifconfig auto").
* (4) it is easier to manage when an interface has addresses
* with the same interface identifier, than to have multiple addresses
* with different interface identifiers.
*/
ifa = (struct ifaddr *)in6ifa_ifpforlinklocal(ifp, 0); /* 0 is OK? */
if (ifa)
ib = (struct in6_ifaddr *)ifa;
else
return NULL;
/* prefixlen + ifidlen must be equal to 128 */
plen0 = in6_mask2len(&ib->ia_prefixmask.sin6_addr, NULL);
if (prefixlen != plen0) {
nd6log((LOG_INFO, "in6_ifadd: wrong prefixlen for %s "
"(prefix=%d ifid=%d)\n",
if_name(ifp), prefixlen, 128 - plen0));
return NULL;
}
/* make ifaddr */
bzero(&ifra, sizeof(ifra));
/*
* in6_update_ifa() does not use ifra_name, but we accurately set it
* for safety.
*/
strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
ifra.ifra_addr.sin6_family = AF_INET6;
ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6);
/* prefix */
ifra.ifra_addr.sin6_addr = pr->ndpr_prefix.sin6_addr;
ifra.ifra_addr.sin6_addr.s6_addr32[0] &= mask.s6_addr32[0];
ifra.ifra_addr.sin6_addr.s6_addr32[1] &= mask.s6_addr32[1];
ifra.ifra_addr.sin6_addr.s6_addr32[2] &= mask.s6_addr32[2];
ifra.ifra_addr.sin6_addr.s6_addr32[3] &= mask.s6_addr32[3];
/* interface ID */
ifra.ifra_addr.sin6_addr.s6_addr32[0] |=
(ib->ia_addr.sin6_addr.s6_addr32[0] & ~mask.s6_addr32[0]);
ifra.ifra_addr.sin6_addr.s6_addr32[1] |=
(ib->ia_addr.sin6_addr.s6_addr32[1] & ~mask.s6_addr32[1]);
ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
(ib->ia_addr.sin6_addr.s6_addr32[2] & ~mask.s6_addr32[2]);
ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
(ib->ia_addr.sin6_addr.s6_addr32[3] & ~mask.s6_addr32[3]);
/* new prefix mask. */
ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
ifra.ifra_prefixmask.sin6_family = AF_INET6;
bcopy(&mask, &ifra.ifra_prefixmask.sin6_addr,
sizeof(ifra.ifra_prefixmask.sin6_addr));
/* lifetimes. */
ifra.ifra_lifetime.ia6t_vltime = pr->ndpr_vltime;
ifra.ifra_lifetime.ia6t_pltime = pr->ndpr_pltime;
/* XXX: scope zone ID? */
ifra.ifra_flags |= IN6_IFF_AUTOCONF; /* obey autoconf */
/*
* Make sure that we do not have this address already. This should
* usually not happen, but we can still see this case, e.g., if we
* have manually configured the exact address to be configured.
*/
if (in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr) != NULL) {
/* this should be rare enough to make an explicit log */
log(LOG_INFO, "in6_ifadd: %s is already configured\n",
ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr));
return (NULL);
}
/*
* Allocate ifaddr structure, link into chain, etc.
* If we are going to create a new address upon receiving a multicasted
* RA, we need to impose a random delay before starting DAD.
* [draft-ietf-ipv6-rfc2462bis-02.txt, Section 5.4.2]
*/
updateflags = 0;
if (mcast)
updateflags |= IN6_IFAUPDATE_DADDELAY;
if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0) {
nd6log((LOG_ERR,
"in6_ifadd: failed to make ifaddr %s on %s (errno=%d)\n",
ip6_sprintf(ip6buf, &ifra.ifra_addr.sin6_addr),
if_name(ifp), error));
return (NULL); /* ifaddr must not have been allocated. */
}
ia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
return (ia); /* this is always non-NULL */
}
/*
* ia0 - corresponding public address
*/
int
in6_tmpifadd(const struct in6_ifaddr *ia0, int forcegen, int delay)
{
struct ifnet *ifp = ia0->ia_ifa.ifa_ifp;
struct in6_ifaddr *newia, *ia;
struct in6_aliasreq ifra;
int i, error;
int trylimit = 3; /* XXX: adhoc value */
int updateflags;
u_int32_t randid[2];
time_t vltime0, pltime0;
bzero(&ifra, sizeof(ifra));
strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name));
ifra.ifra_addr = ia0->ia_addr;
/* copy prefix mask */
ifra.ifra_prefixmask = ia0->ia_prefixmask;
/* clear the old IFID */
for (i = 0; i < 4; i++) {
ifra.ifra_addr.sin6_addr.s6_addr32[i] &=
ifra.ifra_prefixmask.sin6_addr.s6_addr32[i];
}
again:
if (in6_get_tmpifid(ifp, (u_int8_t *)randid,
(const u_int8_t *)&ia0->ia_addr.sin6_addr.s6_addr[8], forcegen)) {
nd6log((LOG_NOTICE, "in6_tmpifadd: failed to find a good "
"random IFID\n"));
return (EINVAL);
}
ifra.ifra_addr.sin6_addr.s6_addr32[2] |=
(randid[0] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[2]));
ifra.ifra_addr.sin6_addr.s6_addr32[3] |=
(randid[1] & ~(ifra.ifra_prefixmask.sin6_addr.s6_addr32[3]));
/*
* in6_get_tmpifid() quite likely provided a unique interface ID.
* However, we may still have a chance to see collision, because
* there may be a time lag between generation of the ID and generation
* of the address. So, we'll do one more sanity check.
*/
for (ia = in6_ifaddr; ia; ia = ia->ia_next) {
if (IN6_ARE_ADDR_EQUAL(&ia->ia_addr.sin6_addr,
&ifra.ifra_addr.sin6_addr)) {
if (trylimit-- == 0) {
/*
* Give up. Something strange should have
* happened.
*/
nd6log((LOG_NOTICE, "in6_tmpifadd: failed to "
"find a unique random IFID\n"));
return (EEXIST);
}
forcegen = 1;
goto again;
}
}
/*
* The Valid Lifetime is the lower of the Valid Lifetime of the
* public address or TEMP_VALID_LIFETIME.
* The Preferred Lifetime is the lower of the Preferred Lifetime
* of the public address or TEMP_PREFERRED_LIFETIME -
* DESYNC_FACTOR.
*/
if (ia0->ia6_lifetime.ia6t_vltime != ND6_INFINITE_LIFETIME) {
vltime0 = IFA6_IS_INVALID(ia0) ? 0 :
(ia0->ia6_lifetime.ia6t_vltime -
(time_second - ia0->ia6_updatetime));
if (vltime0 > ip6_temp_valid_lifetime)
vltime0 = ip6_temp_valid_lifetime;
} else
vltime0 = ip6_temp_valid_lifetime;
if (ia0->ia6_lifetime.ia6t_pltime != ND6_INFINITE_LIFETIME) {
pltime0 = IFA6_IS_DEPRECATED(ia0) ? 0 :
(ia0->ia6_lifetime.ia6t_pltime -
(time_second - ia0->ia6_updatetime));
if (pltime0 > ip6_temp_preferred_lifetime - ip6_desync_factor){
pltime0 = ip6_temp_preferred_lifetime -
ip6_desync_factor;
}
} else
pltime0 = ip6_temp_preferred_lifetime - ip6_desync_factor;
ifra.ifra_lifetime.ia6t_vltime = vltime0;
ifra.ifra_lifetime.ia6t_pltime = pltime0;
/*
* A temporary address is created only if this calculated Preferred
* Lifetime is greater than REGEN_ADVANCE time units.
*/
if (ifra.ifra_lifetime.ia6t_pltime <= ip6_temp_regen_advance)
return (0);
/* XXX: scope zone ID? */
ifra.ifra_flags |= (IN6_IFF_AUTOCONF|IN6_IFF_TEMPORARY);
/* allocate ifaddr structure, link into chain, etc. */
updateflags = 0;
if (delay)
updateflags |= IN6_IFAUPDATE_DADDELAY;
if ((error = in6_update_ifa(ifp, &ifra, NULL, updateflags)) != 0)
return (error);
newia = in6ifa_ifpwithaddr(ifp, &ifra.ifra_addr.sin6_addr);
if (newia == NULL) { /* XXX: can it happen? */
nd6log((LOG_ERR,
"in6_tmpifadd: ifa update succeeded, but we got "
"no ifaddr\n"));
return (EINVAL); /* XXX */
}
newia->ia6_ndpr = ia0->ia6_ndpr;
newia->ia6_ndpr->ndpr_refcnt++;
/*
* A newly added address might affect the status of other addresses.
* XXX: when the temporary address is generated with a new public
* address, the onlink check is redundant. However, it would be safe
* to do the check explicitly everywhere a new address is generated,
* and, in fact, we surely need the check when we create a new
* temporary address due to deprecation of an old temporary address.
*/
pfxlist_onlink_check();
return (0);
}
static int
in6_init_prefix_ltimes(struct nd_prefix *ndpr)
{
if (ndpr->ndpr_pltime == ND6_INFINITE_LIFETIME)
ndpr->ndpr_preferred = 0;
else
ndpr->ndpr_preferred = time_second + ndpr->ndpr_pltime;
if (ndpr->ndpr_vltime == ND6_INFINITE_LIFETIME)
ndpr->ndpr_expire = 0;
else
ndpr->ndpr_expire = time_second + ndpr->ndpr_vltime;
return 0;
}
static void
in6_init_address_ltimes(struct nd_prefix *new, struct in6_addrlifetime *lt6)
{
/* init ia6t_expire */
if (lt6->ia6t_vltime == ND6_INFINITE_LIFETIME)
lt6->ia6t_expire = 0;
else {
lt6->ia6t_expire = time_second;
lt6->ia6t_expire += lt6->ia6t_vltime;
}
/* init ia6t_preferred */
if (lt6->ia6t_pltime == ND6_INFINITE_LIFETIME)
lt6->ia6t_preferred = 0;
else {
lt6->ia6t_preferred = time_second;
lt6->ia6t_preferred += lt6->ia6t_pltime;
}
}
/*
* Delete all the routing table entries that use the specified gateway.
* XXX: this function causes search through all entries of routing table, so
* it shouldn't be called when acting as a router.
*/
void
rt6_flush(struct in6_addr *gateway, struct ifnet *ifp)
{
struct radix_node_head *rnh = rt_tables[0][AF_INET6];
int s = splnet();
/* We'll care only link-local addresses */
if (!IN6_IS_ADDR_LINKLOCAL(gateway)) {
splx(s);
return;
}
RADIX_NODE_HEAD_LOCK(rnh);
rnh->rnh_walktree(rnh, rt6_deleteroute, (void *)gateway);
RADIX_NODE_HEAD_UNLOCK(rnh);
splx(s);
}
static int
rt6_deleteroute(struct radix_node *rn, void *arg)
{
#define SIN6(s) ((struct sockaddr_in6 *)s)
struct rtentry *rt = (struct rtentry *)rn;
struct in6_addr *gate = (struct in6_addr *)arg;
if (rt->rt_gateway == NULL || rt->rt_gateway->sa_family != AF_INET6)
return (0);
if (!IN6_ARE_ADDR_EQUAL(gate, &SIN6(rt->rt_gateway)->sin6_addr)) {
return (0);
}
/*
* Do not delete a static route.
* XXX: this seems to be a bit ad-hoc. Should we consider the
* 'cloned' bit instead?
*/
if ((rt->rt_flags & RTF_STATIC) != 0)
return (0);
/*
* We delete only host route. This means, in particular, we don't
* delete default route.
*/
if ((rt->rt_flags & RTF_HOST) == 0)
return (0);
return (rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway,
rt_mask(rt), rt->rt_flags, 0));
#undef SIN6
}
int
nd6_setdefaultiface(int ifindex)
{
int error = 0;
if (ifindex < 0 || if_index < ifindex)
return (EINVAL);
if (ifindex != 0 && !ifnet_byindex(ifindex))
return (EINVAL);
if (nd6_defifindex != ifindex) {
nd6_defifindex = ifindex;
if (nd6_defifindex > 0)
nd6_defifp = ifnet_byindex(nd6_defifindex);
else
nd6_defifp = NULL;
/*
* Our current implementation assumes one-to-one maping between
* interfaces and links, so it would be natural to use the
* default interface as the default link.
*/
scope6_setdefault(nd6_defifp);
}
return (error);
}
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