routed/af.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)af.c        5.8 (Berkeley) 6/18/88";
#endif /* not lint */

#include "defs.h"

/*
 * Address family support routines
 */
int     inet_hash(), inet_netmatch(), inet_output(),
        inet_portmatch(), inet_portcheck(),
        inet_checkhost(), inet_rtflags(), inet_sendroute(), inet_canon();
char    *inet_format();

#define NIL     { 0 }
#define INET \
        { inet_hash,            inet_netmatch,          inet_output, \
          inet_portmatch,       inet_portcheck,         inet_checkhost, \
          inet_rtflags,         inet_sendroute,         inet_canon, \
          inet_format \
        }

struct afswitch afswitch[AF_MAX] = {
        NIL,            /* 0- unused */
        NIL,            /* 1- Unix domain, unused */
        INET,           /* Internet */
};

int af_max = sizeof(afswitch) / sizeof(afswitch[0]);

struct sockaddr_in inet_default = { AF_INET, INADDR_ANY };

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

        n = inet_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);
        hp->afh_hosthash &= 0x7fffffff;
}

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

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

/*
 * Verify the message is from the right port.
 */
inet_portmatch(sin)
        register struct sockaddr_in *sin;
{

        return (sin->sin_port == sp->s_port);
}

/*
 * Verify the message is from a "trusted" port.
 */
inet_portcheck(sin)
        struct sockaddr_in *sin;
{

        return (ntohs(sin->sin_port) <= IPPORT_RESERVED);
}

/*
 * Internet output routine.
 */
inet_output(s, flags, sin, size)
        int s, flags;
        struct sockaddr_in *sin;
        int size;
{
        struct sockaddr_in dst;

        dst = *sin;
        sin = &dst;
        if (sin->sin_port == 0)
                sin->sin_port = sp->s_port;
        if (sendto(s, packet, size, flags, sin, sizeof (*sin)) < 0)
                perror("sendto");
}

/*
 * Return 1 if the address is believed
 * for an Internet host -- THIS IS A KLUDGE.
 */
inet_checkhost(sin)
        struct sockaddr_in *sin;
{
        u_long i = ntohl(sin->sin_addr.s_addr);

#ifndef IN_EXPERIMENTAL
#define IN_EXPERIMENTAL(i)      (((long) (i) & 0xe0000000) == 0xe0000000)
#endif

        if (IN_EXPERIMENTAL(i) || sin->sin_port != 0)
                return (0);
        if (i != 0 && (i & 0xff000000) == 0)
                return (0);
        for (i = 0; i < sizeof(sin->sin_zero)/sizeof(sin->sin_zero[0]); i++)
                if (sin->sin_zero[i])
                        return (0);
        return (1);
}

inet_canon(sin)
        struct sockaddr_in *sin;
{

        sin->sin_port = 0;
}

char *
inet_format(sin)
        struct sockaddr_in *sin;
{
        char *inet_ntoa();

        return (inet_ntoa(sin->sin_addr));
}