libuuid/common/etheraddr.c

	etheraddr.c revision 948f2876ce2a3010558f4f6937e16086ebcd36f2
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <stdlib.h>
#include <stdio.h>
#include <strings.h>
#include <stropts.h>
#include <unistd.h>
#include <uuid/uuid.h>
#include <sys/sockio.h>
#include <libdlpi.h>
#include <libdllink.h>
#include <sys/utsname.h>

#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "etheraddr.h"

/*
 * debugging flag
 */
static  int debug = 0;

static void get_etheraddr(void *arg, const char *linkname);

/*
 * get an individual arp entry
 */
int
arp_get(uuid_node_t *node)
{
    struct utsname name;
    struct arpreq ar;
    struct hostent *hp;
    struct sockaddr_in *sin;
    int s;

    if (uname(&name) == -1) {
        return (-1);
    }
    (void) memset(&ar, 0, sizeof (ar));
    ar.arp_pa.sa_family = AF_INET;
    /* LINTED pointer */
    sin = (struct sockaddr_in *)&ar.arp_pa;
    sin->sin_family = AF_INET;
    sin->sin_addr.s_addr = inet_addr(name.nodename);
    if (sin->sin_addr.s_addr == (in_addr_t)-1) {
        hp = gethostbyname(name.nodename);
        if (hp == NULL) {
            return (-1);
        }
        (void) memcpy(&sin->sin_addr, hp->h_addr,
            sizeof (sin->sin_addr));
    }
    s = socket(AF_INET, SOCK_DGRAM, 0);
    if (s < 0) {
        return (-1);
    }
    if (ioctl(s, SIOCGARP, (caddr_t)&ar) < 0) {
        (void) close(s);
        return (-1);
    }
    (void) close(s);
    if (ar.arp_flags & ATF_COM) {
        bcopy(&ar.arp_ha.sa_data, node, 6);
    } else
        return (-1);
    return (0);
}

/*
 * Name:    get_ethernet_address
 *
 * Description: Obtains the system ethernet address.
 *
 * Returns: 0 on success, non-zero otherwise.  The system ethernet
 *      address is copied into the passed-in variable.
 */
int
get_ethernet_address(uuid_node_t *node)
{
    walker_arg_t    state;

    if (arp_get(node) == 0)
        return (0);

    /*
     * Try to get physical (ethernet) address from network interfaces.
     */
    state.wa_addrvalid = B_FALSE;
    if (dladm_walk(get_etheraddr, &state) == 0 && state.wa_addrvalid) {
        bcopy(state.wa_etheraddr, node, state.wa_etheraddrlen);
    }

    return (state.wa_addrvalid ? 0 : -1);
}

/*
 * Get the physical address via dlpi and update the flag to true upon success.
 */
static void
get_etheraddr(void *arg, const char *linkname)
{
    int     retval;
    dlpi_handle_t   dh;
    walker_arg_t    *statep = arg;

    if (!(statep->wa_addrvalid)) {
        if (debug)
            (void) printf("get_etheraddr: opening %s\n", linkname);
        if ((retval = dlpi_open(linkname, &dh, 0)) != DLPI_SUCCESS) {
            if (debug) {
                (void) fprintf(stderr, "get_etheraddr: "
                    "cannot open link: \"%s\" %s\n",
                    linkname, retval);
            }
            return;
        }

        if (debug) {
            (void) printf("get_etheraddr: getting ethernet address"
                " from link: %s\n", linkname);
        }
        statep->wa_etheraddrlen = DLPI_PHYSADDR_MAX;
        retval = dlpi_get_physaddr(dh, DL_CURR_PHYS_ADDR,
            statep->wa_etheraddr, &(statep->wa_etheraddrlen));
        if (debug) {
            (void) fprintf(stderr, "get_etheraddr: "
                "dlpi_get_physaddr: \"%s\" %s\n", linkname, retval);
        }

        if (retval == DLPI_SUCCESS)
            statep->wa_addrvalid = B_TRUE;

        dlpi_close(dh);
    }
}