/*
 * 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.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/sockio.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>

#include <netinet/in.h>
#include <netinet/in_var.h>
#ifndef __NetBSD__
#include <netinet/if_ether.h>
#endif

#include <netinet6/in6.h>
#include <netinet6/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_ifattach.h>
#include <netinet6/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>

static	struct in6_addr llsol;

struct in6_addr **in6_iflladdr = NULL;
unsigned long in6_maxmtu = 0;

int found_first_ifid = 0;
#define IFID_LEN 8
static char first_ifid[IFID_LEN];

static void ieee802_to_eui64 __P((u_int8_t *, u_int8_t *));

static void
ieee802_to_eui64(dst, src)
	u_int8_t *dst;
	u_int8_t *src;
{
	dst[0] = src[0];
	dst[1] = src[1];
	dst[2] = src[2];
	dst[3] = 0xff;
	dst[4] = 0xfe;
	dst[5] = src[3];
	dst[6] = src[4];
	dst[7] = src[5];
}

/*
 * find first ifid on list of interfaces.
 */
int
in6_ifattach_getifid(ifp0)
	struct ifnet *ifp0;
{
	struct ifnet *ifp;
	struct ifaddr *ifa;
	u_int8_t *addr = NULL;
	int addrlen = 0;
	struct sockaddr_dl *sdl;

	if (found_first_ifid)
		return 0;

	for (ifp = ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next) {
		if (ifp0 != NULL && ifp0 != ifp)
			continue;
		for (ifa = ifp->if_addrlist.tqh_first;
		     ifa;
		     ifa = ifa->ifa_list.tqe_next) {
			if (ifa->ifa_addr->sa_family != AF_LINK)
				continue;
			sdl = (struct sockaddr_dl *)ifa->ifa_addr;
			if (sdl == NULL)
				continue;
			if (sdl->sdl_alen == 0)
				continue;
			switch (ifp->if_type) {
			case IFT_ETHER:
			case IFT_FDDI:
			case IFT_ATM:
			/* what others? */
				addr = LLADDR(sdl);
				addrlen = sdl->sdl_alen;
				goto found;
			default:
				break;
			}
		}
	}
	printf("failed to get EUI64");
	return EADDRNOTAVAIL;

found:
	switch (addrlen) {
	case 6:
		ieee802_to_eui64(first_ifid, addr);
		found_first_ifid = 1;
		break;
	case 8:
		bcopy(addr, first_ifid, 8);
		found_first_ifid = 1;
		break;
	default:
		break;
	}

	if (found_first_ifid) {
		printf("got EUI64 from %s, "
			"value %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n",
			ifp->if_xname,
			first_ifid[0] & 0xff, first_ifid[1] & 0xff,
			first_ifid[2] & 0xff, first_ifid[3] & 0xff,
			first_ifid[4] & 0xff, first_ifid[5] & 0xff,
			first_ifid[6] & 0xff, first_ifid[7] & 0xff);
		return 0;
	} else {
		printf("failed to get EUI64");
		return EADDRNOTAVAIL;
	}
}

/*
 * add link-local address to *pseudo* p2p interfaces.
 * get called when the first MAC address is made available in in6_ifattach().
 */
void
in6_ifattach_p2p()
{
	struct ifnet *ifp;

	/* prevent infinite loop. just in case. */
	if (! found_first_ifid)
		return;

	for (ifp = ifnet.tqh_first; ifp; ifp = ifp->if_list.tqe_next) {
		switch (ifp->if_type) {
		case IFT_GIF:
		case IFT_FAITH:
			/* pseudo interfaces - safe to initialize here */
			in6_ifattach(ifp, IN6_IFT_P2P, 0, 0);
			break;
		case IFT_SLIP:
			/* IPv6 is not supported */
			break;
		case IFT_PPP:
			/* this is not a pseudo interface, skip it */
			break;
		default:
			break;
		}
	}
}

void
in6_ifattach(ifp, type, laddr, noloop)
	struct ifnet *ifp;
	u_int type;
	caddr_t laddr;
	int noloop;
	/* xxx sizeof(laddr) */
{
	static size_t if_indexlim = 8;
	struct sockaddr_in6 mltaddr;
	struct sockaddr_in6 mltmask;
	struct sockaddr_in6 gate;
	struct sockaddr_in6 mask;

	struct in6_ifaddr *ia, *ib, *oia;
	struct ifaddr *ifa;
	int rtflag = 0;

	if (type == IN6_IFT_P2P && found_first_ifid == 0) {
		printf("%s: no ifid available yet for IPv6 link-local address\n",
			ifp->if_xname);
		return;
	}

	if ((ifp->if_flags & IFF_MULTICAST) == 0) {
		printf("%s: no multicast allowed, IPv6 is not enabled\n",
			ifp->if_xname);
		return;
	}
	    
	/*
	 * We have some arrays that should be indexed by if_index.
	 * since if_index will grow dynamically, they should grow too.
	 *	struct in6_addr **in6_iflladdr
	 */
	if (in6_iflladdr == NULL || if_index >= if_indexlim) {
		size_t n;
		caddr_t q;

		while(if_index >= if_indexlim)
			if_indexlim <<= 1;

		/* grow in6_iflladdr */
		n = if_indexlim * sizeof(struct in6_addr *);
		q = (caddr_t)malloc(n, M_IFADDR, M_WAITOK);
		bzero(q, n);
		if (in6_iflladdr) {
			bcopy((caddr_t)in6_iflladdr, q, n/2);
			free((caddr_t)in6_iflladdr, M_IFADDR);
		}
		in6_iflladdr = (struct in6_addr **)q;
	}

	/*
	 * To prevent to assign link-local address to PnP network
	 * cards multiple times. 
	 * This is lengthy for P2P and LOOP but works.
	 */
	ifa = TAILQ_FIRST(&ifp->if_addrlist);
	if (ifa != NULL) {
		for ( ; ifa; ifa = TAILQ_NEXT(ifa, ifa_list)) {
			if (ifa->ifa_addr->sa_family != AF_INET6)
				continue;
			if (IN6_IS_ADDR_LINKLOCAL(&satosin6(ifa->ifa_addr)->sin6_addr))
				return;
		}
	} else
		TAILQ_INIT(&ifp->if_addrlist);

	/*
	 * link-local address
	 */
	ia = (struct in6_ifaddr *)malloc(sizeof(*ia), M_IFADDR, M_WAITOK);
	bzero((caddr_t)ia, sizeof(*ia));
	ia->ia_ifa.ifa_addr =    (struct sockaddr *)&ia->ia_addr;
	ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr;
	ia->ia_ifa.ifa_netmask = (struct sockaddr *)&ia->ia_prefixmask;
	ia->ia_ifp = ifp;
	TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
	/*
	 * Also link into the IPv6 address chain beginning with in6_ifaddr.
	 * kazu opposed it, but itojun & jinmei wanted.
	 */
	if ((oia = in6_ifaddr) != NULL) {
		for (; oia->ia_next; oia = oia->ia_next)
			continue;
		oia->ia_next = ia;
	} else
		in6_ifaddr = ia;

	ia->ia_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
	ia->ia_prefixmask.sin6_family = AF_INET6;
	ia->ia_prefixmask.sin6_addr = in6mask64;

	bzero(&ia->ia_addr, sizeof(struct sockaddr_in6));
	ia->ia_addr.sin6_len = sizeof(struct sockaddr_in6);
	ia->ia_addr.sin6_family = AF_INET6;
	ia->ia_addr.sin6_addr.s6_addr16[0] = htons(0xfe80);
	ia->ia_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
	ia->ia_addr.sin6_addr.s6_addr32[1] = 0;

	switch (type) {
	case IN6_IFT_LOOP:
		ia->ia_addr.sin6_addr.s6_addr32[2] = 0;
		ia->ia_addr.sin6_addr.s6_addr32[3] = htonl(1);
		break;
	case IN6_IFT_802:
		ia->ia_ifa.ifa_rtrequest = nd6_rtrequest;
		ia->ia_ifa.ifa_flags |= RTF_CLONING;
		rtflag = RTF_CLONING;
		/* fall through */
	case IN6_IFT_P2P802:
		if (laddr == NULL)
			break;
		ieee802_to_eui64(&ia->ia_addr.sin6_addr.s6_addr8[8], laddr);
		/* set global bit */
		ia->ia_addr.sin6_addr.s6_addr8[8] |= 0x02;
		if (! found_first_ifid) {
			if (in6_ifattach_getifid(ifp) == 0)
				in6_ifattach_p2p();
		}
		break;
	case IN6_IFT_P2P:
		bcopy((caddr_t)first_ifid,
		      (caddr_t)&ia->ia_addr.sin6_addr.s6_addr8[8],
		      IFID_LEN);
		break;
	}

	ia->ia_ifa.ifa_metric = ifp->if_metric;

	if (ifp->if_ioctl != NULL) {
		int s;
		int error;

		/*
		 * give the interface a chance to initialize, in case this
		 * is the first address to be added.
		 */
		s = splimp();
		error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia);
		splx(s);

		if (error) {
			switch (error) {
			case EAFNOSUPPORT:
				printf("%s: IPv6 is not supported\n",
					ifp->if_xname);
				break;
			default:
				printf("SIOCSIFADDR(%s) returned %d\n",
					ifp->if_xname, error);
				break;
			}

			/* undo changes */
			TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);
			if (oia)
				oia->ia_next = ia->ia_next;
			else
				in6_ifaddr = ia->ia_next;
			free(ia, M_IFADDR);
			return;
		}
	}

	/* add route to the interface. */
	rtrequest(RTM_ADD,
		  (struct sockaddr *)&ia->ia_addr,
		  (struct sockaddr *)&ia->ia_addr, 
		  (struct sockaddr *)&ia->ia_prefixmask,
		  RTF_UP|rtflag,
		  (struct rtentry **)0);
	ia->ia_flags |= IFA_ROUTE;


	if (type == IN6_IFT_P2P || type == IN6_IFT_P2P802) {
		/*
		 * route local address to loopback
		 */
		bzero(&gate, sizeof(gate));
		gate.sin6_len = sizeof(struct sockaddr_in6);
		gate.sin6_family = AF_INET6;
		gate.sin6_addr = in6addr_loopback;
		bzero(&mask, sizeof(mask));
		mask.sin6_len = sizeof(struct sockaddr_in6);
		mask.sin6_family = AF_INET6;
		mask.sin6_addr = in6mask64;
		rtrequest(RTM_ADD,
			  (struct sockaddr *)&ia->ia_addr,
			  (struct sockaddr *)&gate,
			  (struct sockaddr *)&mask,
			  RTF_UP|RTF_HOST,
			  (struct rtentry **)0);
	}

	/*
	 * loopback address
	 */
	ib = (struct in6_ifaddr *)NULL;
	if (type == IN6_IFT_LOOP) {
		ib = (struct in6_ifaddr *)
			malloc(sizeof(*ib), M_IFADDR, M_WAITOK);
		bzero((caddr_t)ib, sizeof(*ib));
		ib->ia_ifa.ifa_addr = (struct sockaddr *)&ib->ia_addr;
		ib->ia_ifa.ifa_dstaddr = (struct sockaddr *)&ib->ia_dstaddr;
		ib->ia_ifa.ifa_netmask = (struct sockaddr *)&ib->ia_prefixmask;
		ib->ia_ifp = ifp;

		ia->ia_next = ib;
		TAILQ_INSERT_TAIL(&ifp->if_addrlist, (struct ifaddr *)ib,
			ifa_list);

		ib->ia_prefixmask.sin6_len = sizeof(struct sockaddr_in6);
		ib->ia_prefixmask.sin6_family = AF_INET6;
		ib->ia_prefixmask.sin6_addr = in6mask128;
		ib->ia_addr.sin6_len = sizeof(struct sockaddr_in6);
		ib->ia_addr.sin6_family = AF_INET6;
		ib->ia_addr.sin6_addr = in6addr_loopback;
#ifdef __bsdi__
		/*
		 * It is necessary to set the loopback address to the dstaddr
		 * field at least for BSDI. Without this setting, the BSDI
		 * version of ifa_ifwithroute() rejects to add a route
		 * to the loopback interface. 
		 */
		ib->ia_dstaddr.sin6_len = sizeof(struct sockaddr_in6);
		ib->ia_dstaddr.sin6_family = AF_INET6;
		ib->ia_dstaddr.sin6_addr = in6addr_loopback;
#endif /* __bsdi__ */

		ib->ia_ifa.ifa_metric = ifp->if_metric;

		rtrequest(RTM_ADD,
			  (struct sockaddr *)&ib->ia_addr,
			  (struct sockaddr *)&ib->ia_addr, 
			  (struct sockaddr *)&ib->ia_prefixmask,
			  RTF_UP|RTF_HOST,
			  (struct rtentry **)0);

		ib->ia_flags |= IFA_ROUTE;
	}

	/*
	 * join multicast
	 */
	if (ifp->if_flags & IFF_MULTICAST) {
		int error;	/* not used */

#if !defined(__FreeBSD__) || __FreeBSD__ < 3
		/* Restore saved multicast addresses(if any). */
		in6_restoremkludge(ia, ifp);
#endif

		bzero(&mltmask, sizeof(mltmask));
		mltmask.sin6_len = sizeof(struct sockaddr_in6);
		mltmask.sin6_family = AF_INET6;
		mltmask.sin6_addr = in6mask32;

		/*
		 * join link-local all-nodes address
		 */
		bzero(&mltaddr, sizeof(mltaddr));
		mltaddr.sin6_len = sizeof(struct sockaddr_in6);
		mltaddr.sin6_family = AF_INET6;
		mltaddr.sin6_addr = in6addr_linklocal_allnodes;
		mltaddr.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
		rtrequest(RTM_ADD,
			  (struct sockaddr *)&mltaddr,
			  (struct sockaddr *)&ia->ia_addr, 
			  (struct sockaddr *)&mltmask,
			  RTF_UP|RTF_CLONING,  /* xxx */
			  (struct rtentry **)0);
		(void)in6_addmulti(&mltaddr.sin6_addr, ifp, &error);

		if (type == IN6_IFT_LOOP) {
			/*
			 * join node-local all-nodes address
			 */
			mltaddr.sin6_addr = in6addr_nodelocal_allnodes;
			rtrequest(RTM_ADD,
				  (struct sockaddr *)&mltaddr,
				  (struct sockaddr *)&ib->ia_addr, 
				  (struct sockaddr *)&mltmask,
				  RTF_UP,
				  (struct rtentry **)0);
			(void)in6_addmulti(&mltaddr.sin6_addr, ifp, &error);
		} else {
			/*
			 * join solicited multicast address
			 */
			bzero(&llsol, sizeof(llsol));
			llsol.s6_addr16[0] = htons(0xff02);
			llsol.s6_addr16[1] = htons(ifp->if_index);
			llsol.s6_addr32[1] = 0;
			llsol.s6_addr32[2] = htonl(1);
			llsol.s6_addr32[3] = ia->ia_addr.sin6_addr.s6_addr32[3];
			llsol.s6_addr8[12] = 0xff;
			(void)in6_addmulti(&llsol, ifp, &error);
		}
	}

	/* update dynamically. */
	in6_iflladdr[ifp->if_index] = &ia->ia_addr.sin6_addr;
	if (in6_maxmtu < ifp->if_mtu)
		in6_maxmtu = ifp->if_mtu;

	/* initialize NDP variables */
	nd6_ifattach(ifp);

	/* mark the address TENTATIVE, if needed. */
	switch (ifp->if_type) {
	case IFT_ETHER:
	case IFT_FDDI:
#if 0
	case IFT_ATM:
	case IFT_SLIP:
	case IFT_PPP:
#endif
		ia->ia6_flags |= IN6_IFF_TENTATIVE;
		/* nd6_dad_start() will be called in in6_if_up */
		break;
	case IFT_GIF:
	case IFT_LOOP:
	case IFT_FAITH:
	default:
		break;
	}

	return;
}

void
in6_ifdetach(ifp)
	struct ifnet *ifp;
{
	struct in6_ifaddr *ia, *oia;
	struct ifaddr *ifa;
	struct rtentry *rt;
	short rtflags;

	for (ifa = ifp->if_addrlist.tqh_first; ifa; ifa = ifa->ifa_list.tqe_next) {
		if (ifa->ifa_addr->sa_family != AF_INET6
		 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) {
			continue;
		}

		ia = (struct in6_ifaddr *)ifa;

		/* remove from the routing table */
		if ((ia->ia_flags & IFA_ROUTE)
		 && (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) {
			rtflags = rt->rt_flags;
			rtfree(rt);
			rtrequest(RTM_DELETE,
				(struct sockaddr *)&ia->ia_addr,
				(struct sockaddr *)&ia->ia_addr, 
				(struct sockaddr *)&ia->ia_prefixmask,
				rtflags, (struct rtentry **)0);
		}

		/* remove from the linked list */
		TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list);

		/* also remove from the IPv6 address chain(itojun&jinmei) */
		oia = ia;
		if (oia == (ia = in6_ifaddr))
			in6_ifaddr = ia->ia_next;
		else {
			while (ia->ia_next && (ia->ia_next != oia))
				ia = ia->ia_next;
			if (ia->ia_next)
				ia->ia_next = oia->ia_next;
			else
				printf("Didn't unlink in6ifaddr from list\n");
		}

		free(ia, M_IFADDR);
	}
}