InfoMagic Internet Tools 1993 July/Internet Tools.iso/RockRidge/ip/trace/tcpdump-2.2.1/nametoaddr.c

C/C++ Source or Header | 1991-02-04 | 4.9 KB | 259 lines

/*
 * Copyright (c) 1988-1990 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: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Name to id translation routines used by the scanner.
 * These functions are not time critical.
 */

#ifndef lint
static char rcsid[] =
    "@(#) $Header: nametoaddr.c,v 1.9 91/02/04 16:56:46 mccanne Exp $ (LBL)";
#endif

#include <stdio.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netdb.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <errno.h>
#include <arpa/inet.h>

#ifdef ultrix
#include <sys/time.h>
#include <rpc/types.h>
#include <nfs/nfs.h>
#endif

#include "interface.h"
#include "etherent.h"
#include "nametoaddr.h"

/*
 *  Convert host name to internet address.
 *  Return 0 upon failure.
 */
u_long **
s_nametoaddr(name)
    char *name;
{
#ifndef h_addr
    static u_long *hlist[2];
#endif
    u_long **p;
    struct hostent *hp;

    if (hp = gethostbyname(name)) {
#ifndef h_addr
        hlist[0] = (u_long *)hp->h_addr;
        NTOHL(hp->h_addr);
        return hlist;
#else
        for (p = (u_long **)hp->h_addr_list; *p; ++p)
            NTOHL(**p);
        return (u_long **)hp->h_addr_list;
#endif
    }
    else
        return 0;
}

/*
 *  Convert net name to internet address.
 *  Return 0 upon failure.
 */
u_long
s_nametonetaddr(name)
    char *name;
{
    struct netent *np;

    if (np = getnetbyname(name))
        return np->n_net;
    else
        return 0;
}

/*
 * Convert a port name to its port and protocol numbers.
 * We assume only TCP or UDP.
 * Return 0 upon failure.
 */
s_nametoport(name, port, proto)
    char *name;
    int *port;
    int *proto;
{
    struct servent *sp;
    char *other;

    sp = getservbyname(name, (char *)0);
    if (sp != 0) {
        NTOHS(sp->s_port);
        *port = sp->s_port;
        *proto = s_nametoproto(sp->s_proto);
        /*
         * We need to check /etc/services for ambiguous entries.
         * If we find the ambiguous entry, and it has the
         * same port number, change the proto to PROTO_UNDEF
         * so both TCP and UDP will be checked.
         */
        if (*proto == IPPROTO_TCP)
            other = "udp";
        else
            other = "tcp";

        sp = getservbyname(name, other);
        if (sp != 0) {
            NTOHS(sp->s_port);
            if (*port != sp->s_port)
                /* Can't handle ambigous names that refer
                   to different port numbers. */
                warning("ambiguous port %s in /etc/services",
                    name);
            *proto = PROTO_UNDEF;
        }
        return 1;
    }
#ifdef ultrix
    /* Special hack in case NFS isn't in /etc/services */
    if (strcmp(name, "nfs") == 0) {
        *port = NFS_PORT;
        *proto = PROTO_UNDEF;
        return 1;
    }
#endif
    return 0;
}

int
s_nametoproto(str)
    char *str;
{
    struct protoent *p;

    p = getprotobyname(str);
    if (p != 0)
        return p->p_proto;
    else
        return PROTO_UNDEF;
}

#include "etherproto.h"

int
s_nametoeproto(s)
    char *s;
{
    struct eproto *p = eproto_db;

    while (p->s != 0) {
        if (strcmp(p->s, s) == 0)
            return p->p;
        p += 1;
    }
    return PROTO_UNDEF;
}

/* Hex digit to integer. */
static inline int
xdtoi(c)
{
    if (isdigit(c))
        return c - '0';
    else if (islower(c))
        return c - 'a' + 10;
    else
        return c - 'A' + 10;
}

u_long
atoin(s)
    char *s;
{
    u_long addr = 0;
    u_int n;

    while (1) {
        n = 0;
        while (*s && *s != '.')
            n = n * 10 + *s++ - '0';
        addr <<= 8;
        addr |= n & 0xff;
        if (*s == '\0')
            return addr;
        ++s;
    }
    /* NOTREACHED */
}


/*
 * Convert 's' which has the form "xx:xx:xx:xx:xx:xx" into a new
 * ethernet address.  Assumes 's' is well formed.
 */
u_char *
ETHER_aton(s)
    char *s;
{
    register u_char *ep, *e;
    register u_int d;

    e = ep = (u_char *)malloc(6);

    while (*s) {
        if (*s == ':')
            s += 1;
        d = xdtoi(*s++);
        if (isxdigit(*s)) {
            d <<= 4;
            d |= xdtoi(*s++);
        }
        *ep++ = d;
    }

    return e;
}

#ifndef ETHER_SERVICE
u_char *
ETHER_hostton(name)
    char *name;
{
    struct etherent *ep;
    FILE *fp;
    u_char *ap;

    fp = fopen(ETHERS_FILE, "r");
    if (fp != 0) {
        while (ep = next_etherent(fp)) {
            if (strcmp(ep->name, name) == 0) {
                ap = (u_char *)malloc(6);
                bcopy(ep->addr, ap, 6);
                return ap;
            }
        }
    }
    return (u_char *)0;
}
#endif