BSD 4_3 release

[unix-history] / usr / src / sys / netinet / in.c

/*
* Copyright (c) 1982, 1986 Regents of the University of California.
* All rights reserved.  The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*
*      @(#)in.c        7.2 (Berkeley) 11/23/86
*/

#include "param.h"
#include "ioctl.h"
#include "mbuf.h"
#include "protosw.h"
#include "socket.h"
#include "socketvar.h"
#include "uio.h"
#include "dir.h"
#include "user.h"
#include "in_systm.h"
#include "../net/if.h"
#include "../net/route.h"
#include "../net/af.h"
#include "in.h"
#include "in_var.h"

#ifdef INET
inet_hash(sin, hp)
       register struct sockaddr_in *sin;
       struct afhash *hp;
{
       register u_long n;

       n = in_netof(sin->sin_addr);
       if (n)
           while ((n & 0xff) == 0)
               n >>= 8;
       hp->afh_nethash = n;
       hp->afh_hosthash = ntohl(sin->sin_addr.s_addr);
}

inet_netmatch(sin1, sin2)
       struct sockaddr_in *sin1, *sin2;
{

       return (in_netof(sin1->sin_addr) == in_netof(sin2->sin_addr));
}

/*
* Formulate an Internet address from network + host.
*/
struct in_addr
in_makeaddr(net, host)
       u_long net, host;
{
       register struct in_ifaddr *ia;
       register u_long mask;
       u_long addr;

       if (IN_CLASSA(net))
               mask = IN_CLASSA_HOST;
       else if (IN_CLASSB(net))
               mask = IN_CLASSB_HOST;
       else
               mask = IN_CLASSC_HOST;
       for (ia = in_ifaddr; ia; ia = ia->ia_next)
               if ((ia->ia_netmask & net) == ia->ia_net) {
                       mask = ~ia->ia_subnetmask;
                       break;
               }
       addr = htonl(net | (host & mask));
       return (*(struct in_addr *)&addr);
}

/*
* 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
               net = i & IN_CLASSC_NET;

       /*
        * 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);
}

/*
* Return the host portion of an internet address.
*/
u_long
in_lnaof(in)
       struct in_addr in;
{
       register u_long i = ntohl(in.s_addr);
       register u_long net, host;
       register struct in_ifaddr *ia;

       if (IN_CLASSA(i)) {
               net = i & IN_CLASSA_NET;
               host = i & IN_CLASSA_HOST;
       } else if (IN_CLASSB(i)) {
               net = i & IN_CLASSB_NET;
               host = i & IN_CLASSB_HOST;
       } else {
               net = i & IN_CLASSC_NET;
               host = i & IN_CLASSC_HOST;
       }

       /*
        * Check whether network is a subnet;
        * if so, use the modified interpretation of `host'.
        */
       for (ia = in_ifaddr; ia; ia = ia->ia_next)
               if (net == ia->ia_net)
                       return (host &~ ia->ia_subnetmask);
       return (host);
}

#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 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
               net = i & IN_CLASSC_NET;

       for (ia = in_ifaddr; ia; ia = ia->ia_next)
               if (net == (subnetsarelocal ? ia->ia_net : ia->ia_subnet))
                       return (1);
       return (0);
}

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;
       u_long tmp;
       struct ifaddr *ifa;
       struct mbuf *m;
       int error;

       /*
        * 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 SIOCSIFADDR:
       case SIOCSIFNETMASK:
       case SIOCSIFDSTADDR:
               if (!suser())
                       return (u.u_error);

               if (ifp == 0)
                       panic("in_control");
               if (ia == (struct in_ifaddr *)0) {
                       m = m_getclr(M_WAIT, MT_IFADDR);
                       if (m == (struct mbuf *)NULL)
                               return (ENOBUFS);
                       if (ia = in_ifaddr) {
                               for ( ; ia->ia_next; ia = ia->ia_next)
                                       ;
                               ia->ia_next = mtod(m, struct in_ifaddr *);
                       } else
                               in_ifaddr = mtod(m, struct in_ifaddr *);
                       ia = mtod(m, struct in_ifaddr *);
                       if (ifa = ifp->if_addrlist) {
                               for ( ; ifa->ifa_next; ifa = ifa->ifa_next)
                                       ;
                               ifa->ifa_next = (struct ifaddr *) ia;
                       } else
                               ifp->if_addrlist = (struct ifaddr *) ia;
                       ia->ia_ifp = ifp;
                       IA_SIN(ia)->sin_family = AF_INET;
                       if (ifp != &loif)
                               in_interfaces++;
               }
               break;

       case SIOCSIFBRDADDR:
               if (!suser())
                       return (u.u_error);
               /* FALLTHROUGH */

       default:
               if (ia == (struct in_ifaddr *)0)
                       return (EADDRNOTAVAIL);
               break;
       }

       switch (cmd) {

       case SIOCGIFADDR:
               ifr->ifr_addr = ia->ia_addr;
               break;

       case SIOCGIFBRDADDR:
               if ((ifp->if_flags & IFF_BROADCAST) == 0)
                       return (EINVAL);
               ifr->ifr_dstaddr = ia->ia_broadaddr;
               break;

       case SIOCGIFDSTADDR:
               if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
                       return (EINVAL);
               ifr->ifr_dstaddr = ia->ia_dstaddr;
               break;

       case SIOCGIFNETMASK:
#define satosin(sa)     ((struct sockaddr_in *)(sa))
               satosin(&ifr->ifr_addr)->sin_family = AF_INET;
               satosin(&ifr->ifr_addr)->sin_addr.s_addr = htonl(ia->ia_subnetmask);
               break;

       case SIOCSIFDSTADDR:
           {
               struct sockaddr oldaddr;

               if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
                       return (EINVAL);
               oldaddr = ia->ia_dstaddr;
               ia->ia_dstaddr = ifr->ifr_dstaddr;
               if (ifp->if_ioctl &&
                   (error = (*ifp->if_ioctl)(ifp, SIOCSIFDSTADDR, ia))) {
                       ia->ia_dstaddr = oldaddr;
                       return (error);
               }
               if (ia->ia_flags & IFA_ROUTE) {
                       rtinit(&oldaddr, &ia->ia_addr, (int)SIOCDELRT,
                           RTF_HOST);
                       rtinit(&ia->ia_dstaddr, &ia->ia_addr, (int)SIOCADDRT,
                           RTF_HOST|RTF_UP);
               }
           }
               break;

       case SIOCSIFBRDADDR:
               if ((ifp->if_flags & IFF_BROADCAST) == 0)
                       return (EINVAL);
               ia->ia_broadaddr = ifr->ifr_broadaddr;
               tmp = ntohl(satosin(&ia->ia_broadaddr)->sin_addr.s_addr);
               if ((tmp &~ ia->ia_subnetmask) == ~ia->ia_subnetmask)
                       tmp |= ~ia->ia_netmask;
               else if ((tmp &~ ia->ia_subnetmask) == 0)
                       tmp &= ia->ia_netmask;
               ia->ia_netbroadcast.s_addr = htonl(tmp);
               break;

       case SIOCSIFADDR:
               return (in_ifinit(ifp, ia, &ifr->ifr_addr));

       case SIOCSIFNETMASK:
               ia->ia_subnetmask = ntohl(satosin(&ifr->ifr_addr)->sin_addr.s_addr);
               break;

       default:
               if (ifp == 0 || ifp->if_ioctl == 0)
                       return (EOPNOTSUPP);
               return ((*ifp->if_ioctl)(ifp, cmd, data));
       }
       return (0);
}

/*
* Initialize an interface's internet address
* and routing table entry.
*/
in_ifinit(ifp, ia, sin)
       register struct ifnet *ifp;
       register struct in_ifaddr *ia;
       struct sockaddr_in *sin;
{
       register u_long i = ntohl(sin->sin_addr.s_addr);
       struct sockaddr oldaddr;
       struct sockaddr_in netaddr;
       int s = splimp(), error;

       oldaddr = ia->ia_addr;
       ia->ia_addr = *(struct sockaddr *)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, ia))) {
               splx(s);
               ia->ia_addr = oldaddr;
               return (error);
       }

       /*
        * Delete any previous route for an old address.
        */
       bzero((caddr_t)&netaddr, sizeof (netaddr));
       netaddr.sin_family = AF_INET;
       if (ia->ia_flags & IFA_ROUTE) {
               if (ifp->if_flags & IFF_LOOPBACK)
                       rtinit(&oldaddr, &oldaddr, (int)SIOCDELRT, RTF_HOST);
               else if (ifp->if_flags & IFF_POINTOPOINT)
                       rtinit(&ia->ia_dstaddr, &oldaddr, (int)SIOCDELRT,
                           RTF_HOST);
               else {
                       netaddr.sin_addr = in_makeaddr(ia->ia_subnet,
                           INADDR_ANY);
                       rtinit((struct sockaddr *)&netaddr, &oldaddr, 
                           (int)SIOCDELRT, 0);
               }
               ia->ia_flags &= ~IFA_ROUTE;
       }
       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;
       ia->ia_net = i & ia->ia_netmask;
       /*
        * The subnet mask includes at least the standard network part,
        * but may already have been set to a larger value.
        */
       ia->ia_subnetmask |= ia->ia_netmask;
       ia->ia_subnet = i & ia->ia_subnetmask;
       if (ifp->if_flags & IFF_BROADCAST) {
               ia->ia_broadaddr.sa_family = AF_INET;
               ((struct sockaddr_in *)(&ia->ia_broadaddr))->sin_addr =
                       in_makeaddr(ia->ia_subnet, INADDR_BROADCAST);
               ia->ia_netbroadcast.s_addr =
                   htonl(ia->ia_net | (INADDR_BROADCAST &~ ia->ia_netmask));
       }
       splx(s);
       /*
        * Add route for the network.
        */
       if (ifp->if_flags & IFF_LOOPBACK)
               rtinit(&ia->ia_addr, &ia->ia_addr, (int)SIOCADDRT,
                   RTF_HOST|RTF_UP);
       else if (ifp->if_flags & IFF_POINTOPOINT)
               rtinit(&ia->ia_dstaddr, &ia->ia_addr, (int)SIOCADDRT,
                   RTF_HOST|RTF_UP);
       else {
               netaddr.sin_addr = in_makeaddr(ia->ia_subnet, INADDR_ANY);
               rtinit((struct sockaddr *)&netaddr, &ia->ia_addr,
                   (int)SIOCADDRT, RTF_UP);
       }
       ia->ia_flags |= IFA_ROUTE;
       return (0);
}

/*
* Return address info for specified internet network.
*/
struct in_ifaddr *
in_iaonnetof(net)
       u_long net;
{
       register struct in_ifaddr *ia;

       for (ia = in_ifaddr; ia; ia = ia->ia_next)
               if (ia->ia_subnet == net)
                       return (ia);
       return ((struct in_ifaddr *)0);
}

/*
* Return 1 if the address is a local broadcast address.
*/
in_broadcast(in)
       struct in_addr in;
{
       register struct in_ifaddr *ia;

       /*
        * Look through the list of addresses for a match
        * with a broadcast address.
        */
       for (ia = in_ifaddr; ia; ia = ia->ia_next)
           if (((struct sockaddr_in *)&ia->ia_broadaddr)->sin_addr.s_addr ==
               in.s_addr && (ia->ia_ifp->if_flags & IFF_BROADCAST))
                    return (1);
       return (0);
}
#endif