ip_output.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

			break;

		case IP_TOS:
		case IP_TTL:
		case IP_RECVOPTS:
		case IP_RECVRETOPTS:
		case IP_RECVDSTADDR:
			*mp = m = m_get(M_WAIT, MT_SOOPTS);
			m->m_len = sizeof(int);
			switch (optname) {

			case IP_TOS:
				optval = inp->inp_ip.ip_tos;
				break;

			case IP_TTL:
				optval = inp->inp_ip.ip_ttl;
				break;

#define	OPTBIT(bit)	(inp->inp_flags & bit ? 1 : 0)

			case IP_RECVOPTS:
				optval = OPTBIT(INP_RECVOPTS);
				break;

			case IP_RECVRETOPTS:
				optval = OPTBIT(INP_RECVRETOPTS);
				break;

			case IP_RECVDSTADDR:
				optval = OPTBIT(INP_RECVDSTADDR);
				break;
			}
			*mtod(m, int *) = optval;
			break;

		case IP_MULTICAST_IF:
		case IP_MULTICAST_TTL:
		case IP_MULTICAST_LOOP:
		case IP_ADD_MEMBERSHIP:
		case IP_DROP_MEMBERSHIP:
#ifdef NOTUSED_BY_PMON
			error = ip_getmoptions(optname, inp->inp_moptions, mp);
#else
			error = EINVAL;
#endif
			break;

		case IP_PORTRANGE:
			*mp = m = m_get(M_WAIT, MT_SOOPTS);
			m->m_len = sizeof(int);

			if (inp->inp_flags & INP_HIGHPORT)
				optval = IP_PORTRANGE_HIGH;
			else if (inp->inp_flags & INP_LOWPORT)
				optval = IP_PORTRANGE_LOW;
			else
				optval = 0;

			*mtod(m, int *) = optval;
			break;

		case IPSEC_OUTSA:
#ifndef IPSEC
			error = EINVAL;
#else
			s = spltdb();
			if (inp->inp_tdb == NULL) {
				error = ENOENT;
			} else {
				tdbi.spi = inp->inp_tdb->tdb_spi;
				tdbi.dst = inp->inp_tdb->tdb_dst;
				tdbi.proto = inp->inp_tdb->tdb_sproto;
				*mp = m = m_get(M_WAIT, MT_SOOPTS);
				m->m_len = sizeof(tdbi);
				bcopy((caddr_t)&tdbi, mtod(m, caddr_t),
				    (unsigned)m->m_len);
			}
			splx(s);
#endif /* IPSEC */
			break;

		case IP_AUTH_LEVEL:
		case IP_ESP_TRANS_LEVEL:
		case IP_ESP_NETWORK_LEVEL:
#ifndef IPSEC
			*mtod(m, int *) = IPSEC_LEVEL_NONE;
#else
			switch (optname) {
			case IP_AUTH_LEVEL:
				    optval = inp->inp_seclevel[SL_AUTH];
				    break;

			case IP_ESP_TRANS_LEVEL:
				    optval = inp->inp_seclevel[SL_ESP_TRANS];
				    break;

			case IP_ESP_NETWORK_LEVEL:
				    optval = inp->inp_seclevel[SL_ESP_NETWORK];
				    break;
			}
			*mtod(m, int *) = optval;
#endif
			break;
		default:
			error = ENOPROTOOPT;
			break;
		}
		break;
	}
	return (error);
}

/*
 * Set up IP options in pcb for insertion in output packets.
 * Store in mbuf with pointer in pcbopt, adding pseudo-option
 * with destination address if source routed.
 */
int
#ifdef notyet
ip_pcbopts(optname, pcbopt, m)
	int optname;
#else
ip_pcbopts(pcbopt, m)
#endif
	struct mbuf **pcbopt;
	register struct mbuf *m;
{
	register int cnt, optlen;
	register u_char *cp;
	u_char opt;

	/* turn off any old options */
	if (*pcbopt)
		(void)m_free(*pcbopt);
	*pcbopt = 0;
	if (m == (struct mbuf *)0 || m->m_len == 0) {
		/*
		 * Only turning off any previous options.
		 */
		if (m)
			(void)m_free(m);
		return (0);
	}

#ifndef	vax
	if (m->m_len % sizeof(int32_t))
		goto bad;
#endif
	/*
	 * IP first-hop destination address will be stored before
	 * actual options; move other options back
	 * and clear it when none present.
	 */
	if (m->m_data + m->m_len + sizeof(struct in_addr) >= &m->m_dat[MLEN])
		goto bad;
	cnt = m->m_len;
	m->m_len += sizeof(struct in_addr);
	cp = mtod(m, u_char *) + sizeof(struct in_addr);
	ovbcopy(mtod(m, caddr_t), (caddr_t)cp, (unsigned)cnt);
	bzero(mtod(m, caddr_t), sizeof(struct in_addr));

	for (; cnt > 0; cnt -= optlen, cp += optlen) {
		opt = cp[IPOPT_OPTVAL];
		if (opt == IPOPT_EOL)
			break;
		if (opt == IPOPT_NOP)
			optlen = 1;
		else {
			optlen = cp[IPOPT_OLEN];
			if (optlen <= IPOPT_OLEN || optlen > cnt)
				goto bad;
		}
		switch (opt) {

		default:
			break;

		case IPOPT_LSRR:
		case IPOPT_SSRR:
			/*
			 * user process specifies route as:
			 *	->A->B->C->D
			 * D must be our final destination (but we can't
			 * check that since we may not have connected yet).
			 * A is first hop destination, which doesn't appear in
			 * actual IP option, but is stored before the options.
			 */
			if (optlen < IPOPT_MINOFF - 1 + sizeof(struct in_addr))
				goto bad;
			m->m_len -= sizeof(struct in_addr);
			cnt -= sizeof(struct in_addr);
			optlen -= sizeof(struct in_addr);
			cp[IPOPT_OLEN] = optlen;
			/*
			 * Move first hop before start of options.
			 */
			bcopy((caddr_t)&cp[IPOPT_OFFSET+1], mtod(m, caddr_t),
			    sizeof(struct in_addr));
			/*
			 * Then copy rest of options back
			 * to close up the deleted entry.
			 */
			ovbcopy((caddr_t)(&cp[IPOPT_OFFSET+1] +
			    sizeof(struct in_addr)),
			    (caddr_t)&cp[IPOPT_OFFSET+1],
			    (unsigned)cnt + sizeof(struct in_addr));
			break;
		}
	}
	if (m->m_len > MAX_IPOPTLEN + sizeof(struct in_addr))
		goto bad;
	*pcbopt = m;
	return (0);

bad:
	(void)m_free(m);
	return (EINVAL);
}

#ifdef NOTUSED_BY_PMON
/*
 * Set the IP multicast options in response to user setsockopt().
 */
int
ip_setmoptions(optname, imop, m)
	int optname;
	struct ip_moptions **imop;
	struct mbuf *m;
{
	register int error = 0;
	u_char loop;
	register int i;
	struct in_addr addr;
	register struct ip_mreq *mreq;
	register struct ifnet *ifp;
	register struct ip_moptions *imo = *imop;
	struct route ro;
	register struct sockaddr_in *dst;

	if (imo == NULL) {
		/*
		 * No multicast option buffer attached to the pcb;
		 * allocate one and initialize to default values.
		 */
		imo = (struct ip_moptions *)malloc(sizeof(*imo), M_IPMOPTS,
		    M_WAITOK);

		if (imo == NULL)
			return (ENOBUFS);
		*imop = imo;
		imo->imo_multicast_ifp = NULL;
		imo->imo_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
		imo->imo_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
		imo->imo_num_memberships = 0;
	}

	switch (optname) {

	case IP_MULTICAST_IF:
		/*
		 * Select the interface for outgoing multicast packets.
		 */
		if (m == NULL || m->m_len != sizeof(struct in_addr)) {
			error = EINVAL;
			break;
		}
		addr = *(mtod(m, struct in_addr *));
		/*
		 * INADDR_ANY is used to remove a previous selection.
		 * When no interface is selected, a default one is
		 * chosen every time a multicast packet is sent.
		 */
		if (addr.s_addr == INADDR_ANY) {
			imo->imo_multicast_ifp = NULL;
			break;
		}
		/*
		 * The selected interface is identified by its local
		 * IP address.  Find the interface and confirm that
		 * it supports multicasting.
		 */
		INADDR_TO_IFP(addr, ifp);
		if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
			error = EADDRNOTAVAIL;
			break;
		}
		imo->imo_multicast_ifp = ifp;
		break;

	case IP_MULTICAST_TTL:
		/*
		 * Set the IP time-to-live for outgoing multicast packets.
		 */
		if (m == NULL || m->m_len != 1) {
			error = EINVAL;
			break;
		}
		imo->imo_multicast_ttl = *(mtod(m, u_char *));
		break;

	case IP_MULTICAST_LOOP:
		/*
		 * Set the loopback flag for outgoing multicast packets.
		 * Must be zero or one.
		 */
		if (m == NULL || m->m_len != 1 ||
		   (loop = *(mtod(m, u_char *))) > 1) {
			error = EINVAL;
			break;
		}
		imo->imo_multicast_loop = loop;
		break;

	case IP_ADD_MEMBERSHIP:
		/*
		 * Add a multicast group membership.
		 * Group must be a valid IP multicast address.
		 */
		if (m == NULL || m->m_len != sizeof(struct ip_mreq)) {
			error = EINVAL;
			break;
		}
		mreq = mtod(m, struct ip_mreq *);
		if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) {
			error = EINVAL;
			break;
		}
		/*
		 * If no interface address was provided, use the interface of
		 * the route to the given multicast address.
		 */
		if (mreq->imr_interface.s_addr == INADDR_ANY) {
			ro.ro_rt = NULL;
			dst = satosin(&ro.ro_dst);
			dst->sin_len = sizeof(*dst);
			dst->sin_family = AF_INET;
			dst->sin_addr = mreq->imr_multiaddr;
			rtalloc(&ro);
			if (ro.ro_rt == NULL) {
				error = EADDRNOTAVAIL;
				break;
			}
			ifp = ro.ro_rt->rt_ifp;
			rtfree(ro.ro_rt);
		} else {
			INADDR_TO_IFP(mreq->imr_interface, ifp);
		}
		/*
		 * See if we found an interface, and confirm that it
		 * supports multicast.
		 */
		if (ifp == NULL || (ifp->if_flags & IFF_MULTICAST) == 0) {
			error = EADDRNOTAVAIL;
			break;
		}
		/*
		 * See if the membership already exists or if all the
		 * membership slots are full.
		 */
		for (i = 0; i < imo->imo_num_memberships; ++i) {
			if (imo->imo_membership[i]->inm_ifp == ifp &&
			    imo->imo_membership[i]->inm_addr.s_addr
						== mreq->imr_multiaddr.s_addr)
				break;
		}
		if (i < imo->imo_num_memberships) {
			error = EADDRINUSE;
			break;
		}
		if (i == IP_MAX_MEMBERSHIPS) {
			error = ETOOMANYREFS;
			break;
		}
		/*
		 * Everything looks good; add a new record to the multicast
		 * address list for the given interface.
		 */
		if ((imo->imo_membership[i] =
		    in_addmulti(&mreq->imr_multiaddr, ifp)) == NULL) {
			error = ENOBUFS;
			break;
		}
		++imo->imo_num_memberships;
		break;

	case IP_DROP_MEMBERSHIP:
		/*
		 * Drop a multicast group membership.
		 * Group must be a valid IP multicast address.
		 */
		if (m == NULL || m->m_len != sizeof(struct ip_mreq)) {
			error = EINVAL;
			break;
		}
		mreq = mtod(m, struct ip_mreq *);
		if (!IN_MULTICAST(mreq->imr_multiaddr.s_addr)) {
			error = EINVAL;
			break;
		}
		/*
		 * If an interface address was specified, get a pointer
		 * to its ifnet structure.
		 */
		if (mreq->imr_interface.s_addr == INADDR_ANY)
			ifp = NULL;
		else {
			INADDR_TO_IFP(mreq->imr_interface, ifp);
			if (ifp == NULL) {
				error = EADDRNOTAVAIL;
				break;
			}
		}
		/*
		 * Find the membership in the membership array.
		 */
		for (i = 0; i < imo->imo_num_memberships; ++i) {
			if ((ifp == NULL ||
			     imo->imo_membership[i]->inm_ifp == ifp) &&
			     imo->imo_membership[i]->inm_addr.s_addr ==
			     mreq->imr_multiaddr.s_addr)
				break;
		}
		if (i == imo->imo_num_memberships) {
			error = EADDRNOTAVAIL;
			break;
		}
		/*
		 * Give up the multicast address record to which the
		 * membership points.
		 */
		in_delmulti(imo->imo_membership[i]);
		/*
		 * Remove the gap in the membership array.
		 */
		for (++i; i < imo->imo_num_memberships; ++i)
			imo->imo_membership[i-1] = imo->imo_membership[i];
		--imo->imo_num_memberships;
		break;

	default:
		error = EOPNOTSUPP;
		break;
	}

	/*
	 * If all options have default values, no need to keep the mbuf.
	 */
	if (imo->imo_multicast_ifp == NULL &&
	    imo->imo_multicast_ttl == IP_DEFAULT_MULTICAST_TTL &&
	    imo->imo_multicast_loop == IP_DEFAULT_MULTICAST_LOOP &&
	    imo->imo_num_memberships == 0) {
		free(*imop, M_IPMOPTS);
		*imop = NULL;
	}

	return (error);
}

/*
 * Return the IP multicast options in response to user getsockopt().
 */
int
ip_getmoptions(optname, imo, mp)
	int optname;
	register struct ip_moptions *imo;
	register struct mbuf **mp;
{
	u_char *ttl;
	u_char *loop;
	struct in_addr *addr;
	struct in_ifaddr *ia;

	*mp = m_get(M_WAIT, MT_SOOPTS);

	switch (optname) {

	case IP_MULTICAST_IF:
		addr = mtod(*mp, struct in_addr *);
		(*mp)->m_len = sizeof(struct in_addr);
		if (imo == NULL || imo->imo_multicast_ifp == NULL)
			addr->s_addr = INADDR_ANY;
		else {
			IFP_TO_IA(imo->imo_multicast_ifp, ia);
			addr->s_addr = (ia == NULL) ? INADDR_ANY
					: ia->ia_addr.sin_addr.s_addr;
		}
		return (0);

	case IP_MULTICAST_TTL:
		ttl = mtod(*mp, u_char *);
		(*mp)->m_len = 1;
		*ttl = (imo == NULL) ? IP_DEFAULT_MULTICAST_TTL
				     : imo->imo_multicast_ttl;
		return (0);

	case IP_MULTICAST_LOOP:
		loop = mtod(*mp, u_char *);
		(*mp)->m_len = 1;
		*loop = (imo == NULL) ? IP_DEFAULT_MULTICAST_LOOP
				      : imo->imo_multicast_loop;
		return (0);

	default:
		return (EOPNOTSUPP);
	}
}

/*
 * Discard the IP multicast options.
 */
void
ip_freemoptions(imo)
	register struct ip_moptions *imo;
{
	register int i;

	if (imo != NULL) {
		for (i = 0; i < imo->imo_num_memberships; ++i)
			in_delmulti(imo->imo_membership[i]);
		free(imo, M_IPMOPTS);
	}
}
#endif /* NOTUSED_BY_PMON */

/*
 * Routine called from ip_output() to loop back a copy of an IP multicast
 * packet to the input queue of a specified interface.  Note that this
 * calls the output routine of the loopback "driver", but with an interface
 * pointer that might NOT be &loif -- easier than replicating that code here.
 */
static void
ip_mloopback(ifp, m, dst)
	struct ifnet *ifp;
	register struct mbuf *m;
	register struct sockaddr_in *dst;
{
	register struct ip *ip;
	struct mbuf *copym;

	copym = m_copy(m, 0, M_COPYALL);
	if (copym != NULL) {
		/*
		 * We don't bother to fragment if the IP length is greater
		 * than the interface's MTU.  Can this possibly matter?
		 */
		ip = mtod(copym, struct ip *);
		ip->ip_len = htons((u_int16_t)ip->ip_len);
		ip->ip_off = htons((u_int16_t)ip->ip_off);
		ip->ip_sum = 0;
		ip->ip_sum = in_cksum(copym, ip->ip_hl << 2);
		(void) looutput(ifp, copym, sintosa(dst), NULL);
	}
}