BSD 4.4 Lite Kernel Sources

1 files changed, 622 insertions, 0 deletions

diff --git a/sys/netinet/in.c b/sys/netinet/in.c
new file mode 100644
index 0000000..e8b481b
--- /dev/null
+++ b/sys/netinet/in.c
@@ -0,0 +1,622 @@
+/*
+ * Copyright (c) 1982, 1986, 1991, 1993
+ *	The Regents of the University of California.  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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
+ *
+ *	@(#)in.c	8.2 (Berkeley) 11/15/93
+ */
+
+#include <sys/param.h>
+#include <sys/ioctl.h>
+#include <sys/errno.h>
+#include <sys/malloc.h>
+#include <sys/socket.h>
+#include <sys/socketvar.h>
+
+#include <net/if.h>
+#include <net/route.h>
+
+#include <netinet/in_systm.h>
+#include <netinet/in.h>
+#include <netinet/in_var.h>
+#include <netinet/if_ether.h>
+
+#ifdef INET
+/*
+ * Return the network number from an internet address.
+ */
+u_long
+in_netof(in)
+	struct in_addr in;
+{
+	register u_long i = ntohl(in.s_addr);
+	register u_long net;
+	register struct in_ifaddr *ia;
+
+	if (IN_CLASSA(i))
+		net = i & IN_CLASSA_NET;
+	else if (IN_CLASSB(i))
+		net = i & IN_CLASSB_NET;
+	else if (IN_CLASSC(i))
+		net = i & IN_CLASSC_NET;
+	else if (IN_CLASSD(i))
+		net = i & IN_CLASSD_NET;
+	else
+		return (0);
+
+	/*
+	 * Check whether network is a subnet;
+	 * if so, return subnet number.
+	 */
+	for (ia = in_ifaddr; ia; ia = ia->ia_next)
+		if (net == ia->ia_net)
+			return (i & ia->ia_subnetmask);
+	return (net);
+}
+
+#ifndef SUBNETSARELOCAL
+#define	SUBNETSARELOCAL	1
+#endif
+int subnetsarelocal = SUBNETSARELOCAL;
+/*
+ * Return 1 if an internet address is for a ``local'' host
+ * (one to which we have a connection).  If subnetsarelocal
+ * is true, this includes other subnets of the local net.
+ * Otherwise, it includes only the directly-connected (sub)nets.
+ */
+in_localaddr(in)
+	struct in_addr in;
+{
+	register u_long i = ntohl(in.s_addr);
+	register struct in_ifaddr *ia;
+
+	if (subnetsarelocal) {
+		for (ia = in_ifaddr; ia; ia = ia->ia_next)
+			if ((i & ia->ia_netmask) == ia->ia_net)
+				return (1);
+	} else {
+		for (ia = in_ifaddr; ia; ia = ia->ia_next)
+			if ((i & ia->ia_subnetmask) == ia->ia_subnet)
+				return (1);
+	}
+	return (0);
+}
+
+/*
+ * Determine whether an IP address is in a reserved set of addresses
+ * that may not be forwarded, or whether datagrams to that destination
+ * may be forwarded.
+ */
+in_canforward(in)
+	struct in_addr in;
+{
+	register u_long i = ntohl(in.s_addr);
+	register u_long net;
+
+	if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i))
+		return (0);
+	if (IN_CLASSA(i)) {
+		net = i & IN_CLASSA_NET;
+		if (net == 0 || net == (IN_LOOPBACKNET << IN_CLASSA_NSHIFT))
+			return (0);
+	}
+	return (1);
+}
+
+/*
+ * Trim a mask in a sockaddr
+ */
+void
+in_socktrim(ap)
+struct sockaddr_in *ap;
+{
+    register char *cplim = (char *) &ap->sin_addr;
+    register char *cp = (char *) (&ap->sin_addr + 1);
+
+    ap->sin_len = 0;
+    while (--cp > cplim)
+        if (*cp) {
+	    (ap)->sin_len = cp - (char *) (ap) + 1;
+	    break;
+	}
+}
+
+int	in_interfaces;		/* number of external internet interfaces */
+extern	struct ifnet loif;
+
+/*
+ * Generic internet control operations (ioctl's).
+ * Ifp is 0 if not an interface-specific ioctl.
+ */
+/* ARGSUSED */
+in_control(so, cmd, data, ifp)
+	struct socket *so;
+	int cmd;
+	caddr_t data;
+	register struct ifnet *ifp;
+{
+	register struct ifreq *ifr = (struct ifreq *)data;
+	register struct in_ifaddr *ia = 0;
+	register struct ifaddr *ifa;
+	struct in_ifaddr *oia;
+	struct in_aliasreq *ifra = (struct in_aliasreq *)data;
+	struct sockaddr_in oldaddr;
+	int error, hostIsNew, maskIsNew;
+	u_long i;
+
+	/*
+	 * Find address for this interface, if it exists.
+	 */
+	if (ifp)
+		for (ia = in_ifaddr; ia; ia = ia->ia_next)
+			if (ia->ia_ifp == ifp)
+				break;
+
+	switch (cmd) {
+
+	case SIOCAIFADDR:
+	case SIOCDIFADDR:
+		if (ifra->ifra_addr.sin_family == AF_INET)
+		    for (oia = ia; ia; ia = ia->ia_next) {
+			if (ia->ia_ifp == ifp  &&
+			    ia->ia_addr.sin_addr.s_addr ==
+				ifra->ifra_addr.sin_addr.s_addr)
+			    break;
+		}
+		if (cmd == SIOCDIFADDR && ia == 0)
+			return (EADDRNOTAVAIL);
+		/* FALLTHROUGH */
+	case SIOCSIFADDR:
+	case SIOCSIFNETMASK:
+	case SIOCSIFDSTADDR:
+		if ((so->so_state & SS_PRIV) == 0)
+			return (EPERM);
+
+		if (ifp == 0)
+			panic("in_control");
+		if (ia == (struct in_ifaddr *)0) {
+			oia = (struct in_ifaddr *)
+				malloc(sizeof *oia, M_IFADDR, M_WAITOK);
+			if (oia == (struct in_ifaddr *)NULL)
+				return (ENOBUFS);
+			bzero((caddr_t)oia, sizeof *oia);
+			if (ia = in_ifaddr) {
+				for ( ; ia->ia_next; ia = ia->ia_next)
+					continue;
+				ia->ia_next = oia;
+			} else
+				in_ifaddr = oia;
+			ia = oia;
+			if (ifa = ifp->if_addrlist) {
+				for ( ; ifa->ifa_next; ifa = ifa->ifa_next)
+					continue;
+				ifa->ifa_next = (struct ifaddr *) ia;
+			} else
+				ifp->if_addrlist = (struct ifaddr *) 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_sockmask;
+			ia->ia_sockmask.sin_len = 8;
+			if (ifp->if_flags & IFF_BROADCAST) {
+				ia->ia_broadaddr.sin_len = sizeof(ia->ia_addr);
+				ia->ia_broadaddr.sin_family = AF_INET;
+			}
+			ia->ia_ifp = ifp;
+			if (ifp != &loif)
+				in_interfaces++;
+		}
+		break;
+
+	case SIOCSIFBRDADDR:
+		if ((so->so_state & SS_PRIV) == 0)
+			return (EPERM);
+		/* FALLTHROUGH */
+
+	case SIOCGIFADDR:
+	case SIOCGIFNETMASK:
+	case SIOCGIFDSTADDR:
+	case SIOCGIFBRDADDR:
+		if (ia == (struct in_ifaddr *)0)
+			return (EADDRNOTAVAIL);
+		break;
+	}
+	switch (cmd) {
+
+	case SIOCGIFADDR:
+		*((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_addr;
+		break;
+
+	case SIOCGIFBRDADDR:
+		if ((ifp->if_flags & IFF_BROADCAST) == 0)
+			return (EINVAL);
+		*((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_broadaddr;
+		break;
+
+	case SIOCGIFDSTADDR:
+		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
+			return (EINVAL);
+		*((struct sockaddr_in *)&ifr->ifr_dstaddr) = ia->ia_dstaddr;
+		break;
+
+	case SIOCGIFNETMASK:
+		*((struct sockaddr_in *)&ifr->ifr_addr) = ia->ia_sockmask;
+		break;
+
+	case SIOCSIFDSTADDR:
+		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
+			return (EINVAL);
+		oldaddr = ia->ia_dstaddr;
+		ia->ia_dstaddr = *(struct sockaddr_in *)&ifr->ifr_dstaddr;
+		if (ifp->if_ioctl && (error = (*ifp->if_ioctl)
+					(ifp, SIOCSIFDSTADDR, (caddr_t)ia))) {
+			ia->ia_dstaddr = oldaddr;
+			return (error);
+		}
+		if (ia->ia_flags & IFA_ROUTE) {
+			ia->ia_ifa.ifa_dstaddr = (struct sockaddr *)&oldaddr;
+			rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
+			ia->ia_ifa.ifa_dstaddr =
+					(struct sockaddr *)&ia->ia_dstaddr;
+			rtinit(&(ia->ia_ifa), (int)RTM_ADD, RTF_HOST|RTF_UP);
+		}
+		break;
+
+	case SIOCSIFBRDADDR:
+		if ((ifp->if_flags & IFF_BROADCAST) == 0)
+			return (EINVAL);
+		ia->ia_broadaddr = *(struct sockaddr_in *)&ifr->ifr_broadaddr;
+		break;
+
+	case SIOCSIFADDR:
+		return (in_ifinit(ifp, ia,
+		    (struct sockaddr_in *) &ifr->ifr_addr, 1));
+
+	case SIOCSIFNETMASK:
+		i = ifra->ifra_addr.sin_addr.s_addr;
+		ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr = i);
+		break;
+
+	case SIOCAIFADDR:
+		maskIsNew = 0;
+		hostIsNew = 1;
+		error = 0;
+		if (ia->ia_addr.sin_family == AF_INET) {
+			if (ifra->ifra_addr.sin_len == 0) {
+				ifra->ifra_addr = ia->ia_addr;
+				hostIsNew = 0;
+			} else if (ifra->ifra_addr.sin_addr.s_addr ==
+					       ia->ia_addr.sin_addr.s_addr)
+				hostIsNew = 0;
+		}
+		if (ifra->ifra_mask.sin_len) {
+			in_ifscrub(ifp, ia);
+			ia->ia_sockmask = ifra->ifra_mask;
+			ia->ia_subnetmask =
+			     ntohl(ia->ia_sockmask.sin_addr.s_addr);
+			maskIsNew = 1;
+		}
+		if ((ifp->if_flags & IFF_POINTOPOINT) &&
+		    (ifra->ifra_dstaddr.sin_family == AF_INET)) {
+			in_ifscrub(ifp, ia);
+			ia->ia_dstaddr = ifra->ifra_dstaddr;
+			maskIsNew  = 1; /* We lie; but the effect's the same */
+		}
+		if (ifra->ifra_addr.sin_family == AF_INET &&
+		    (hostIsNew || maskIsNew))
+			error = in_ifinit(ifp, ia, &ifra->ifra_addr, 0);
+		if ((ifp->if_flags & IFF_BROADCAST) &&
+		    (ifra->ifra_broadaddr.sin_family == AF_INET))
+			ia->ia_broadaddr = ifra->ifra_broadaddr;
+		return (error);
+
+	case SIOCDIFADDR:
+		in_ifscrub(ifp, ia);
+		if ((ifa = ifp->if_addrlist) == (struct ifaddr *)ia)
+			ifp->if_addrlist = ifa->ifa_next;
+		else {
+			while (ifa->ifa_next &&
+			       (ifa->ifa_next != (struct ifaddr *)ia))
+				    ifa = ifa->ifa_next;
+			if (ifa->ifa_next)
+				ifa->ifa_next = ((struct ifaddr *)ia)->ifa_next;
+			else
+				printf("Couldn't unlink inifaddr from ifp\n");
+		}
+		oia = ia;
+		if (oia == (ia = in_ifaddr))
+			in_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 inifadr from list\n");
+		}
+		IFAFREE((&oia->ia_ifa));
+		break;
+
+	default:
+		if (ifp == 0 || ifp->if_ioctl == 0)
+			return (EOPNOTSUPP);
+		return ((*ifp->if_ioctl)(ifp, cmd, data));
+	}
+	return (0);
+}
+
+/*
+ * Delete any existing route for an interface.
+ */
+void
+in_ifscrub(ifp, ia)
+	register struct ifnet *ifp;
+	register struct in_ifaddr *ia;
+{
+
+	if ((ia->ia_flags & IFA_ROUTE) == 0)
+		return;
+	if (ifp->if_flags & (IFF_LOOPBACK|IFF_POINTOPOINT))
+		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, RTF_HOST);
+	else
+		rtinit(&(ia->ia_ifa), (int)RTM_DELETE, 0);
+	ia->ia_flags &= ~IFA_ROUTE;
+}
+
+/*
+ * Initialize an interface's internet address
+ * and routing table entry.
+ */
+in_ifinit(ifp, ia, sin, scrub)
+	register struct ifnet *ifp;
+	register struct in_ifaddr *ia;
+	struct sockaddr_in *sin;
+	int scrub;
+{
+	register u_long i = ntohl(sin->sin_addr.s_addr);
+	struct sockaddr_in oldaddr;
+	int s = splimp(), flags = RTF_UP, error, ether_output();
+
+	oldaddr = ia->ia_addr;
+	ia->ia_addr = *sin;
+	/*
+	 * Give the interface a chance to initialize
+	 * if this is its first address,
+	 * and to validate the address if necessary.
+	 */
+	if (ifp->if_ioctl &&
+	    (error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia))) {
+		splx(s);
+		ia->ia_addr = oldaddr;
+		return (error);
+	}
+	if (ifp->if_output == ether_output) { /* XXX: Another Kludge */
+		ia->ia_ifa.ifa_rtrequest = arp_rtrequest;
+		ia->ia_ifa.ifa_flags |= RTF_CLONING;
+	}
+	splx(s);
+	if (scrub) {
+		ia->ia_ifa.ifa_addr = (struct sockaddr *)&oldaddr;
+		in_ifscrub(ifp, ia);
+		ia->ia_ifa.ifa_addr = (struct sockaddr *)&ia->ia_addr;
+	}
+	if (IN_CLASSA(i))
+		ia->ia_netmask = IN_CLASSA_NET;
+	else if (IN_CLASSB(i))
+		ia->ia_netmask = IN_CLASSB_NET;
+	else
+		ia->ia_netmask = IN_CLASSC_NET;
+	/*
+	 * The subnet mask usually includes at least the standard network part,
+	 * but may may be smaller in the case of supernetting.
+	 * If it is set, we believe it.
+	 */
+	if (ia->ia_subnetmask == 0) {
+		ia->ia_subnetmask = ia->ia_netmask;
+		ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask);
+	} else
+		ia->ia_netmask &= ia->ia_subnetmask;
+	ia->ia_net = i & ia->ia_netmask;
+	ia->ia_subnet = i & ia->ia_subnetmask;
+	in_socktrim(&ia->ia_sockmask);
+	/*
+	 * Add route for the network.
+	 */
+	ia->ia_ifa.ifa_metric = ifp->if_metric;
+	if (ifp->if_flags & IFF_BROADCAST) {
+		ia->ia_broadaddr.sin_addr.s_addr =
+			htonl(ia->ia_subnet | ~ia->ia_subnetmask);
+		ia->ia_netbroadcast.s_addr =
+			htonl(ia->ia_net | ~ ia->ia_netmask);
+	} else if (ifp->if_flags & IFF_LOOPBACK) {
+		ia->ia_ifa.ifa_dstaddr = ia->ia_ifa.ifa_addr;
+		flags |= RTF_HOST;
+	} else if (ifp->if_flags & IFF_POINTOPOINT) {
+		if (ia->ia_dstaddr.sin_family != AF_INET)
+			return (0);
+		flags |= RTF_HOST;
+	}
+	if ((error = rtinit(&(ia->ia_ifa), (int)RTM_ADD, flags)) == 0)
+		ia->ia_flags |= IFA_ROUTE;
+	/*
+	 * If the interface supports multicast, join the "all hosts"
+	 * multicast group on that interface.
+	 */
+	if (ifp->if_flags & IFF_MULTICAST) {
+		struct in_addr addr;
+
+		addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP);
+		in_addmulti(&addr, ifp);
+	}
+	return (error);
+}
+
+
+/*
+ * Return 1 if the address might be a local broadcast address.
+ */
+in_broadcast(in, ifp)
+	struct in_addr in;
+        struct ifnet *ifp;
+{
+	register struct ifaddr *ifa;
+	u_long t;
+
+	if (in.s_addr == INADDR_BROADCAST ||
+	    in.s_addr == INADDR_ANY)
+		return 1;
+	if ((ifp->if_flags & IFF_BROADCAST) == 0)
+		return 0;
+	t = ntohl(in.s_addr);
+	/*
+	 * Look through the list of addresses for a match
+	 * with a broadcast address.
+	 */
+#define ia ((struct in_ifaddr *)ifa)
+	for (ifa = ifp->if_addrlist; ifa; ifa = ifa->ifa_next)
+		if (ifa->ifa_addr->sa_family == AF_INET &&
+		    (in.s_addr == ia->ia_broadaddr.sin_addr.s_addr ||
+		     in.s_addr == ia->ia_netbroadcast.s_addr ||
+		     /*
+		      * Check for old-style (host 0) broadcast.
+		      */
+		     t == ia->ia_subnet || t == ia->ia_net))
+			    return 1;
+	return (0);
+#undef ia
+}
+/*
+ * Add an address to the list of IP multicast addresses for a given interface.
+ */
+struct in_multi *
+in_addmulti(ap, ifp)
+	register struct in_addr *ap;
+	register struct ifnet *ifp;
+{
+	register struct in_multi *inm;
+	struct ifreq ifr;
+	struct in_ifaddr *ia;
+	int s = splnet();
+
+	/*
+	 * See if address already in list.
+	 */
+	IN_LOOKUP_MULTI(*ap, ifp, inm);
+	if (inm != NULL) {
+		/*
+		 * Found it; just increment the reference count.
+		 */
+		++inm->inm_refcount;
+	}
+	else {
+		/*
+		 * New address; allocate a new multicast record
+		 * and link it into the interface's multicast list.
+		 */
+		inm = (struct in_multi *)malloc(sizeof(*inm),
+		    M_IPMADDR, M_NOWAIT);
+		if (inm == NULL) {
+			splx(s);
+			return (NULL);
+		}
+		inm->inm_addr = *ap;
+		inm->inm_ifp = ifp;
+		inm->inm_refcount = 1;
+		IFP_TO_IA(ifp, ia);
+		if (ia == NULL) {
+			free(inm, M_IPMADDR);
+			splx(s);
+			return (NULL);
+		}
+		inm->inm_ia = ia;
+		inm->inm_next = ia->ia_multiaddrs;
+		ia->ia_multiaddrs = inm;
+		/*
+		 * Ask the network driver to update its multicast reception
+		 * filter appropriately for the new address.
+		 */
+		((struct sockaddr_in *)&ifr.ifr_addr)->sin_family = AF_INET;
+		((struct sockaddr_in *)&ifr.ifr_addr)->sin_addr = *ap;
+		if ((ifp->if_ioctl == NULL) ||
+		    (*ifp->if_ioctl)(ifp, SIOCADDMULTI,(caddr_t)&ifr) != 0) {
+			ia->ia_multiaddrs = inm->inm_next;
+			free(inm, M_IPMADDR);
+			splx(s);
+			return (NULL);
+		}
+		/*
+		 * Let IGMP know that we have joined a new IP multicast group.
+		 */
+		igmp_joingroup(inm);
+	}
+	splx(s);
+	return (inm);
+}
+
+/*
+ * Delete a multicast address record.
+ */
+int
+in_delmulti(inm)
+	register struct in_multi *inm;
+{
+	register struct in_multi **p;
+	struct ifreq ifr;
+	int s = splnet();
+
+	if (--inm->inm_refcount == 0) {
+		/*
+		 * No remaining claims to this record; let IGMP know that
+		 * we are leaving the multicast group.
+		 */
+		igmp_leavegroup(inm);
+		/*
+		 * Unlink from list.
+		 */
+		for (p = &inm->inm_ia->ia_multiaddrs;
+		     *p != inm;
+		     p = &(*p)->inm_next)
+			 continue;
+		*p = (*p)->inm_next;
+		/*
+		 * Notify the network driver to update its multicast reception
+		 * filter.
+		 */
+		((struct sockaddr_in *)&(ifr.ifr_addr))->sin_family = AF_INET;
+		((struct sockaddr_in *)&(ifr.ifr_addr))->sin_addr =
+								inm->inm_addr;
+		(*inm->inm_ifp->if_ioctl)(inm->inm_ifp, SIOCDELMULTI,
+							     (caddr_t)&ifr);
+		free(inm, M_IPMADDR);
+	}
+	splx(s);
+}
+#endif