/*
 * lib/krb5/os/localaddr.c
 *
 * Copyright 1990,1991,2000 by the Massachusetts Institute of Technology.
 * All Rights Reserved.
 *
 * Export of this software from the United States of America may
 *   require a specific license from the United States Government.
 *   It is the responsibility of any person or organization contemplating
 *   export to obtain such a license before exporting.
 * 
 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
 * distribute this software and its documentation for any purpose and
 * without fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright notice and
 * this permission notice appear in supporting documentation, and that
 * the name of M.I.T. not be used in advertising or publicity pertaining
 * to distribution of the software without specific, written prior
 * permission.  Furthermore if you modify this software you must label
 * your software as modified software and not distribute it in such a
 * fashion that it might be confused with the original M.I.T. software.
 * M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is" without express
 * or implied warranty.
 * 
 *
 * Return the protocol addresses supported by this host.
 *
 * XNS support is untested, but "Should just work".
 */

#define NEED_SOCKETS
#include "k5-int.h"

#if !defined(HAVE_MACSOCK_H) && !defined(_MSDOS) && !defined(_WIN32)

/* needed for solaris, harmless elsewhere... */
#define BSD_COMP
#include <sys/ioctl.h>
#include <sys/time.h>
#include <errno.h>
#include <stddef.h>
#include <ctype.h>

#if defined(TEST) || defined(DEBUG)
# define FAI_PREFIX krb5int
# include "fake-addrinfo.c"
#endif

#ifdef TEST
# define Tprintf(X) printf X
# define Tperror(X) perror(X)
#else
# define Tprintf(X) (void) X
# define Tperror(X) (void)(X)
#endif

/*
 * The SIOCGIF* ioctls require a socket.
 * It doesn't matter *what* kind of socket they use, but it has to be
 * a socket.
 *
 * Of course, you can't just ask the kernel for a socket of arbitrary
 * type; you have to ask for one with a valid type.
 *
 */
#ifdef HAVE_NETINET_IN_H

#include <netinet/in.h>

#ifndef USE_AF
#define USE_AF AF_INET
#define USE_TYPE SOCK_DGRAM
#define USE_PROTO 0
#endif

#endif

#ifdef KRB5_USE_NS

#include <netns/ns.h>

#ifndef USE_AF
#define USE_AF AF_NS
#define USE_TYPE SOCK_DGRAM
#define USE_PROTO 0		/* guess */
#endif

#endif
/*
 * Add more address families here.
 */

extern int errno;

/*
 * Return all the protocol addresses of this host.
 *
 * We could kludge up something to return all addresses, assuming that
 * they're valid kerberos protocol addresses, but we wouldn't know the
 * real size of the sockaddr or know which part of it was actually the
 * host part.
 *
 * This uses the SIOCGIFCONF, SIOCGIFFLAGS, and SIOCGIFADDR ioctl's.
 */

/* Keep this in sync with kdc/network.c version.  */

/*
 * BSD 4.4 defines the size of an ifreq to be
 * max(sizeof(ifreq), sizeof(ifreq.ifr_name)+ifreq.ifr_addr.sa_len
 * However, under earlier systems, sa_len isn't present, so the size is 
 * just sizeof(struct ifreq).
 */
#ifdef HAVE_SA_LEN
#ifndef max
#define max(a,b) ((a) > (b) ? (a) : (b))
#endif
#define ifreq_size(i) max(sizeof(struct ifreq),\
     sizeof((i).ifr_name)+(i).ifr_addr.sa_len)
#else
#define ifreq_size(i) sizeof(struct ifreq)
#endif /* HAVE_SA_LEN*/

#ifdef HAVE_IFADDRS_H
#include <ifaddrs.h>

#ifdef DEBUG
#include <netinet/in.h>
#include <net/if.h>

void printaddr (struct sockaddr *sa)
{
    char buf[50];
    printf ("%p ", sa);
    switch (sa->sa_family) {
    case AF_INET:
	inet_ntop (AF_INET, &((struct sockaddr_in *)sa)->sin_addr,
		   buf, sizeof (buf));
	printf ("inet %s", buf);
	break;
    case AF_INET6:
	inet_ntop (AF_INET6, &((struct sockaddr_in6 *)sa)->sin6_addr,
		   buf, sizeof (buf));
	printf ("inet6 %s", buf);
	break;
    default:
	printf ("family=%d", sa->sa_family);
	break;
    }
}

void printifaddr (struct ifaddrs *ifp)
{
    printf ("%p={\n", ifp);
/*  printf ("\tnext=%p\n", ifp->ifa_next); */
    printf ("\tname=%s\n", ifp->ifa_name);
    printf ("\tflags=");
    {
	int ch, flags = ifp->ifa_flags;
	printf ("%x", flags);
	ch = '<';
#define X(F) if (flags & IFF_##F) { printf ("%c%s", ch, #F); flags &= ~IFF_##F; ch = ','; }
	X (UP); X (BROADCAST); X (DEBUG); X (LOOPBACK); X (POINTOPOINT);
	X (NOTRAILERS); X (RUNNING); X (NOARP); X (PROMISC); X (ALLMULTI);
	X (OACTIVE); X (SIMPLEX); X (MULTICAST);
	printf (">");
#undef X
    }
    if (ifp->ifa_addr)
	printf ("\n\taddr="), printaddr (ifp->ifa_addr);
    if (ifp->ifa_netmask)
	printf ("\n\tnetmask="), printaddr (ifp->ifa_netmask);
    if (ifp->ifa_broadaddr)
	printf ("\n\tbroadaddr="), printaddr (ifp->ifa_broadaddr);
    if (ifp->ifa_dstaddr)
	printf ("\n\tdstaddr="), printaddr (ifp->ifa_dstaddr);
    if (ifp->ifa_data)
	printf ("\n\tdata=%p", ifp->ifa_data);
    printf ("\n}\n");
}
#endif /* DEBUG */

static int
addr_eq (const struct sockaddr *s1, const struct sockaddr *s2)
{
    if (s1->sa_family != s2->sa_family)
	return 0;
#ifdef HAVE_SA_LEN
    if (s1->sa_len != s2->sa_len)
	return 0;
    return !memcmp (s1, s2, s1->sa_len);
#else
#define CMPTYPE(T,F) (!memcmp(&((T*)s1)->F,&((T*)s2)->F,sizeof(((T*)s1)->F)))
    switch (s1->sa_family) {
    case AF_INET:
	return CMPTYPE (struct sockaddr_in, sin_addr);
    case AF_INET6:
	return CMPTYPE (struct sockaddr_in6, sin6_addr);
    default:
	/* Err on side of duplicate listings.  */
	return 0;
    }
#endif
}
#endif

/*@-usereleased@*/ /* lclint doesn't understand realloc */
static /*@null@*/ void *
grow_or_free (/*@only@*/ void *ptr, size_t newsize)
     /*@*/
{
    void *newptr;
    newptr = realloc (ptr, newsize);
    if (newptr == NULL && newsize != 0) {
	free (ptr);		/* lclint complains but this is right */
	return NULL;
    }
    return newptr;
}
/*@=usereleased@*/

static int
get_ifconf (int s, size_t *lenp, /*@out@*/ char *buf)
    /*@modifies *buf,*lenp@*/
{
    int ret;
    struct ifconf ifc;

    /*@+matchanyintegral@*/
    ifc.ifc_len = *lenp;
    /*@=matchanyintegral@*/
    ifc.ifc_buf = buf;
    memset(buf, 0, *lenp);
    /*@-moduncon@*/
    ret = ioctl (s, SIOCGIFCONF, (char *)&ifc);
    /*@=moduncon@*/
    /*@+matchanyintegral@*/
    *lenp = ifc.ifc_len;
    /*@=matchanyintegral@*/
    return ret;
}

#ifdef SIOCGLIFCONF /* Solaris */
static int
get_lifconf (int af, int s, size_t *lenp, /*@out@*/ char *buf)
    /*@modifies *buf,*lenp@*/
{
    int ret;
    struct lifconf lifc;

    lifc.lifc_family = af;
    lifc.lifc_flags = 0;
    /*@+matchanyintegral@*/
    lifc.lifc_len = *lenp;
    /*@=matchanyintegral@*/
    lifc.lifc_buf = buf;
    memset(buf, 0, *lenp);
    /*@-moduncon@*/
    ret = ioctl (s, SIOCGLIFCONF, (char *)&lifc);
    if (ret)
	Tperror ("SIOCGLIFCONF");
    /*@=moduncon@*/
    /*@+matchanyintegral@*/
    *lenp = lifc.lifc_len;
    /*@=matchanyintegral@*/
    return ret;
}
#endif

/* Return value is errno if internal stuff failed, otherwise zero,
   even in the case where a called function terminated the iteration.

   If one of the callback functions wants to pass back an error
   indication, it should do it via some field pointed to by the DATA
   argument.  */

static int
foreach_localaddr (/*@null@*/ void *data,
		   int (*pass1fn) (/*@null@*/ void *, struct sockaddr *) /*@*/,
		   /*@null@*/ int (*betweenfn) (/*@null@*/ void *) /*@*/,
		   /*@null@*/ int (*pass2fn) (/*@null@*/ void *,
					      struct sockaddr *) /*@*/)
#if defined(DEBUG) || defined(TEST)
     /*@modifies fileSystem@*/
#endif
{
#ifdef HAVE_IFADDRS_H
    struct ifaddrs *ifp_head, *ifp, *ifp2;
    int match;

    if (getifaddrs (&ifp_head) < 0)
	return errno;
    for (ifp = ifp_head; ifp; ifp = ifp->ifa_next) {
#ifdef DEBUG
	printifaddr (ifp);
#endif
	if ((ifp->ifa_flags & IFF_UP) == 0)
	    continue;
	if (ifp->ifa_flags & IFF_LOOPBACK) {
	    ifp->ifa_flags &= ~IFF_UP;
	    continue;
	}
	/* If this address is a duplicate, punt.  */
	match = 0;
	for (ifp2 = ifp_head; ifp2 && ifp2 != ifp; ifp2 = ifp2->ifa_next) {
	    if ((ifp2->ifa_flags & IFF_UP) == 0)
		continue;
	    if (ifp2->ifa_flags & IFF_LOOPBACK)
		continue;
	    if (addr_eq (ifp->ifa_addr, ifp2->ifa_addr)) {
		match = 1;
		ifp->ifa_flags &= ~IFF_UP;
		break;
	    }
	}
	if (match)
	    continue;
	if ((*pass1fn) (data, ifp->ifa_addr))
	    goto punt;
    }
    if (betweenfn && (*betweenfn)(data))
	goto punt;
    if (pass2fn)
	for (ifp = ifp_head; ifp; ifp = ifp->ifa_next) {
	    if (ifp->ifa_flags & IFF_UP)
		if ((*pass2fn) (data, ifp->ifa_addr))
		    goto punt;
	}
 punt:
    freeifaddrs (ifp_head);
    return 0;
#elif defined (SIOCGLIFNUM) /* Solaris 8 and later; Sol 7? */

    /* Okay, this is kind of odd.  We have to use each of the address
       families we care about, because with an AF_INET socket, extra
       interfaces like hme0:1 that have only AF_INET6 addresses will
       cause errors.  Similarly, if hme0 has more AF_INET addresses
       than AF_INET6 addresses, we won't be able to retrieve all of
       the AF_INET addresses if we use an AF_INET6 socket.  Since
       neither family is guaranteed to have the greater number of
       addresses, we should use both.

       If it weren't for this little quirk, we could use a socket of
       any type, and ask for addresses of all types.  At least, it
       seems to work that way.  */

    static const int afs[] = { AF_INET, AF_NS, AF_INET6 };
#define N_AFS (sizeof (afs) / sizeof (afs[0]))
    struct {
	int af;
	int sock;
	void *buf;
	size_t buf_size;
	struct lifnum lifnum;
    } afp[N_AFS];
    int code, i, j;
    int retval = 0, afidx;
    krb5_error_code sock_err = 0;
    struct lifreq *lifr, lifreq, *lifr2;

#define FOREACH_AF() for (afidx = 0; afidx < N_AFS; afidx++)
#define P (afp[afidx])

    /* init */
    FOREACH_AF () {
	P.af = afs[afidx];
	P.sock = -1;
	P.buf = 0;
    }

    /* first pass: get raw data, discard uninteresting addresses, callback */
    FOREACH_AF () {
	Tprintf (("trying af %d...\n", P.af));
	P.sock = socket (P.af, USE_TYPE, USE_PROTO);
	if (P.sock < 0) {
	    sock_err = SOCKET_ERROR;
	    Tperror ("socket");
	    continue;
	}

	P.lifnum.lifn_family = P.af;
	P.lifnum.lifn_flags = 0;
	P.lifnum.lifn_count = 0;
	code = ioctl (P.sock, SIOCGLIFNUM, &P.lifnum);
	if (code) {
	    Tperror ("ioctl(SIOCGLIFNUM)");
	    retval = errno;
	    goto punt;
	}

	P.buf_size = P.lifnum.lifn_count * sizeof (struct lifreq) * 2;
	P.buf = malloc (P.buf_size);
	if (P.buf == NULL) {
	    retval = errno;
	    goto punt;
	}

	code = get_lifconf (P.af, P.sock, &P.buf_size, P.buf);
	if (code < 0) {
	    retval = errno;
	    goto punt;
	}

	for (i = 0; i < P.buf_size; i+= sizeof (*lifr)) {
	    lifr = (struct lifreq *)((caddr_t) P.buf+i);

	    strncpy(lifreq.lifr_name, lifr->lifr_name,
		    sizeof (lifreq.lifr_name));
	    Tprintf (("interface %s\n", lifreq.lifr_name));
	    /*@-moduncon@*/ /* ioctl unknown to lclint */
	    if (ioctl (P.sock, SIOCGLIFFLAGS, (char *)&lifreq) < 0) {
		Tperror ("ioctl(SIOCGLIFFLAGS)");
	    skip:
		/* mark for next pass */
		lifr->lifr_name[0] = '\0';
		continue;
	    }
	    /*@=moduncon@*/

#ifdef IFF_LOOPBACK
	    /* None of the current callers want loopback addresses.  */
	    if (lifreq.lifr_flags & IFF_LOOPBACK) {
		Tprintf (("  loopback\n"));
		goto skip;
	    }
#endif
	    /* Ignore interfaces that are down.  */
	    if ((lifreq.lifr_flags & IFF_UP) == 0) {
		Tprintf (("  down\n"));
		goto skip;
	    }

	    /* Make sure we didn't process this address already.  */
	    for (j = 0; j < i; j += sizeof (*lifr2)) {
		lifr2 = (struct lifreq *)((caddr_t) P.buf+j);
		if (lifr2->lifr_name[0] == '\0')
		    continue;
		if (lifr2->lifr_addr.ss_family == lifr->lifr_addr.ss_family
		    /* Compare address info.  If this isn't good enough --
		       i.e., if random padding bytes turn out to differ
		       when the addresses are the same -- then we'll have
		       to do it on a per address family basis.  */
		    && !memcmp (&lifr2->lifr_addr, &lifr->lifr_addr,
				sizeof (*lifr))) {
		    Tprintf (("  duplicate addr\n"));
		    goto skip;
		}
	    }

	    /*@-moduncon@*/
	    if ((*pass1fn) (data, ss2sa (&lifr->lifr_addr)))
		goto punt;
	    /*@=moduncon@*/
	}
    }

    /* Did we actually get any working sockets?  */
    FOREACH_AF ()
	if (P.sock != -1)
	    goto have_working_socket;
    retval = sock_err;
    goto punt;
have_working_socket:

    /*@-moduncon@*/
    if (betweenfn != NULL && (*betweenfn)(data))
	goto punt;
    /*@=moduncon@*/

    if (pass2fn)
	FOREACH_AF ()
	    if (P.sock >= 0) {
		for (i = 0; i < P.buf_size; i+= sizeof (*lifr)) {
		    lifr = (struct lifreq *)((caddr_t) P.buf+i);

		    if (lifr->lifr_name[0] == '\0')
			/* Marked in first pass to be ignored.  */
			continue;

		    /*@-moduncon@*/
		    if ((*pass2fn) (data, ss2sa (&lifr->lifr_addr)))
			goto punt;
		    /*@=moduncon@*/
		}
	    }
punt:
    FOREACH_AF () {
	/*@-moduncon@*/
	closesocket(P.sock);
	/*@=moduncon@*/
	free (P.buf);
    }

    return retval;

#else
    struct ifreq *ifr, ifreq, *ifr2;
    int s, code;
    int est_if_count = 8;
    size_t est_ifreq_size;
    char *buf = 0;
    size_t current_buf_size = 0, size, n, i, j;
#ifdef SIOCGSIZIFCONF
    int ifconfsize = -1;
#endif
    int retval = 0;
#ifdef SIOCGIFNUM
    int numifs = -1;
#endif

    s = socket (USE_AF, USE_TYPE, USE_PROTO);
    if (s < 0)
	return SOCKET_ERRNO;

    /* At least on NetBSD, an ifreq can hold an IPv4 address, but
       isn't big enough for an IPv6 or ethernet address.  So add a
       little more space.  */
    est_ifreq_size = sizeof (struct ifreq) + 8;
#ifdef SIOCGSIZIFCONF
    code = ioctl (s, SIOCGSIZIFCONF, &ifconfsize);
    if (!code) {
	current_buf_size = ifconfsize;
	est_if_count = ifconfsize / est_ifreq_size;
    }
#elif defined (SIOCGIFNUM)
    code = ioctl (s, SIOCGIFNUM, &numifs);
    if (!code && numifs > 0)
	est_if_count = numifs;
#endif
    if (current_buf_size == 0)
	current_buf_size = est_ifreq_size * est_if_count;
    buf = malloc (current_buf_size);
    if (buf == NULL)
	return errno;

 ask_again:
    size = current_buf_size;
    code = get_ifconf (s, &size, buf);
    if (code < 0) {
	retval = errno;
	/*@-moduncon@*/ /* close() unknown to lclint */
	closesocket (s);
	/*@=moduncon@*/
	free (buf);
	return retval;
    }
    /* Test that the buffer was big enough that another ifreq could've
       fit easily, if the OS wanted to provide one.  That seems to be
       the only indication we get, complicated by the fact that the
       associated address may make the required storage a little
       bigger than the size of an ifreq.  */
    if (current_buf_size - size < sizeof (struct ifreq) + 40
#ifdef SIOCGSIZIFCONF
	&& ifconfsize <= 0
#elif defined (SIOCGIFNUM)
	&& numifs <= 0
#endif
	) {
	size_t new_size;

	est_if_count *= 2;
	new_size = est_ifreq_size * est_if_count;
	buf = grow_or_free (buf, new_size);
	if (buf == 0)
	    return errno;
	current_buf_size = new_size;
	goto ask_again;
    }

    n = size;

    for (i = 0; i < n; i+= ifreq_size(*ifr) ) {
	ifr = (struct ifreq *)((caddr_t) buf+i);

	strncpy(ifreq.ifr_name, ifr->ifr_name, sizeof (ifreq.ifr_name));
	Tprintf (("interface %s\n", ifreq.ifr_name));
	/*@-moduncon@*/ /* ioctl unknown to lclint */
	if (ioctl (s, SIOCGIFFLAGS, (char *)&ifreq) < 0) {
	skip:
	    /* mark for next pass */
	    ifr->ifr_name[0] = '\0';
	    continue;
	}
	/*@=moduncon@*/

#ifdef IFF_LOOPBACK
	/* None of the current callers want loopback addresses.  */
	if (ifreq.ifr_flags & IFF_LOOPBACK) {
	    Tprintf (("  loopback\n"));
	    goto skip;
	}
#endif
	/* Ignore interfaces that are down.  */
	if ((ifreq.ifr_flags & IFF_UP) == 0) {
	    Tprintf (("  down\n"));
	    goto skip;
	}

	/* Make sure we didn't process this address already.  */
	for (j = 0; j < i; j += ifreq_size(*ifr2)) {
	    ifr2 = (struct ifreq *)((caddr_t) buf+j);
	    if (ifr2->ifr_name[0] == '\0')
		continue;
	    if (ifr2->ifr_addr.sa_family == ifr->ifr_addr.sa_family
		&& ifreq_size (*ifr) == ifreq_size (*ifr2)
		/* Compare address info.  If this isn't good enough --
		   i.e., if random padding bytes turn out to differ
		   when the addresses are the same -- then we'll have
		   to do it on a per address family basis.  */
		&& !memcmp (&ifr2->ifr_addr.sa_data, &ifr->ifr_addr.sa_data,
			    (ifreq_size (*ifr)
			     - offsetof (struct ifreq, ifr_addr.sa_data)))) {
		Tprintf (("  duplicate addr\n"));
		goto skip;
	    }
	}

	/*@-moduncon@*/
	if ((*pass1fn) (data, &ifr->ifr_addr))
	    goto punt;
	/*@=moduncon@*/
    }

    /*@-moduncon@*/
    if (betweenfn != NULL && (*betweenfn)(data))
	goto punt;
    /*@=moduncon@*/

    if (pass2fn)
	for (i = 0; i < n; i+= ifreq_size(*ifr) ) {
	    ifr = (struct ifreq *)((caddr_t) buf+i);

	    if (ifr->ifr_name[0] == '\0')
		/* Marked in first pass to be ignored.  */
		continue;

	    /*@-moduncon@*/
	    if ((*pass2fn) (data, &ifr->ifr_addr))
		goto punt;
	    /*@=moduncon@*/
	}
 punt:
    /*@-moduncon@*/
    closesocket(s);
    /*@=moduncon@*/
    free (buf);

    return retval;
#endif /* not HAVE_IFADDRS_H */
}

#ifdef TEST

static int print_addr (/*@unused@*/ void *dataptr, struct sockaddr *sa)
     /*@modifies fileSystem@*/
{
    char hostbuf[NI_MAXHOST];
    int err;
    socklen_t len;
    size_t len_sz;

    printf ("  --> family %2d ", sa->sa_family);
    len_sz = socklen (sa);
    len = (socklen_t) len_sz;
    if ((size_t) len != len_sz)
	abort ();
    err = getnameinfo (sa, len, hostbuf, sizeof (hostbuf),
		       (char *) NULL, 0, NI_NUMERICHOST);
    if (err)
	printf ("<getnameinfo error %d: %s>\n", err, gai_strerror (err));
    else
	printf ("addr %s\n", hostbuf);
    return 0;
}

int main ()
{
    int r;

    (void) setvbuf (stdout, (char *)NULL, _IONBF, 0);
    r = foreach_localaddr (0, print_addr, 0, 0);
    printf ("return value = %d\n", r);
    return 0;
}

#else /* not TESTing */

struct localaddr_data {
    int count, mem_err, cur_idx, cur_size;
    krb5_address **addr_temp;
};

static int
count_addrs (void *P_data, struct sockaddr *a)
     /*@*/
{
    struct localaddr_data *data = P_data;
    switch (a->sa_family) {
    case AF_INET:
#ifdef KRB5_USE_INET6
    case AF_INET6:
#endif
#ifdef KRB5_USE_NS
    case AF_XNS:
#endif
	data->count++;
	break;
    default:
	break;
    }
    return 0;
}

static int
allocate (void *P_data)
     /*@*/
{
    struct localaddr_data *data = P_data;
    int i;
    void *n;

    n = realloc (data->addr_temp,
		 (1 + data->count + data->cur_idx) * sizeof (krb5_address *));
    if (n == 0) {
	data->mem_err++;
	return 1;
    }
    data->addr_temp = n;
    data->cur_size = 1 + data->count + data->cur_idx;
    for (i = data->cur_idx; i <= data->count + data->cur_idx; i++)
	data->addr_temp[i] = 0;
    return 0;
}

static /*@null@*/ krb5_address *
make_addr (int type, size_t length, const void *contents)
    /*@*/
{
    krb5_address *a;
    void *data;

    data = malloc (length);
    if (data == NULL)
	return NULL;
    a = malloc (sizeof (krb5_address));
    if (a == NULL) {
	free (data);
	return NULL;
    }
    memcpy (data, contents, length);
    a->magic = KV5M_ADDRESS;
    a->addrtype = type;
    a->length = length;
    a->contents = data;
    return a;
}

static int
add_addr (void *P_data, struct sockaddr *a)
     /*@modifies *P_data@*/
{
    struct localaddr_data *data = P_data;
    /*@null@*/ krb5_address *address = 0;

    switch (a->sa_family) {
#ifdef HAVE_NETINET_IN_H
    case AF_INET:
	address = make_addr (ADDRTYPE_INET, sizeof (struct in_addr),
			     &((const struct sockaddr_in *) a)->sin_addr);
	if (address == NULL)
	    data->mem_err++;
	break;

#ifdef KRB5_USE_INET6
    case AF_INET6:
    {
	const struct sockaddr_in6 *in = (const struct sockaddr_in6 *) a;
	
	if (IN6_IS_ADDR_LINKLOCAL (&in->sin6_addr))
	    break;

	address = make_addr (ADDRTYPE_INET6, sizeof (struct in6_addr),
			     &in->sin6_addr);
	if (address == NULL)
	    data->mem_err++;
	break;
    }
#endif /* KRB5_USE_INET6 */
#endif /* netinet/in.h */

#ifdef KRB5_USE_NS
    case AF_XNS:
	address = make_addr (ADDRTYPE_XNS, sizeof (struct ns_addr),
			     &((const struct sockaddr_ns *)a)->sns_addr);
	if (address == NULL)
	    data->mem_err++;
	break;
#endif

#ifdef AF_LINK
	/* Some BSD-based systems (e.g. NetBSD 1.5) will include the
	   ethernet address, but we don't want that, at least for now.  */
    case AF_LINK:
	break;
#endif
    /*
     * Add more address families here..
     */
    default:
	break;
    }
#ifdef __LCLINT__
    /* Redundant but unconditional store un-confuses lclint.  */
    data->addr_temp[data->cur_idx] = address;
#endif
    if (address) {
	data->addr_temp[data->cur_idx++] = address;
    }

    return data->mem_err;
}

static krb5_error_code
krb5_os_localaddr_profile (krb5_context context, struct localaddr_data *datap)
{
    krb5_error_code err;
    static const char *const profile_name[] = {
	"libdefaults", "extra_addresses", 0
    };
    char **values;
    char **iter;
    krb5_address **newaddrs;

#ifdef DEBUG
    fprintf (stderr, "looking up extra_addresses foo\n");
#endif

    err = profile_get_values (context->profile, profile_name, &values);
    /* Ignore all errors for now?  */
    if (err)
	return 0;

    for (iter = values; *iter; iter++) {
	char *cp = *iter, *next, *this;
	int i, count;

#ifdef DEBUG
	fprintf (stderr, "  found line: '%s'\n", cp);
#endif

	for (cp = *iter, next = 0; *cp; cp = next) {
	    while (isspace (*cp) || *cp == ',')
		cp++;
	    if (*cp == 0)
		break;
	    /* Start of an address.  */
#ifdef DEBUG
	    fprintf (stderr, "    addr found in '%s'\n", cp);
#endif
	    this = cp;
	    while (*cp != 0 && !isspace(*cp) && *cp != ',')
		cp++;
	    if (*cp != 0) {
		next = cp + 1;
		*cp = 0;
	    } else
		next = cp;
	    /* Got a single address, process it.  */
#ifdef DEBUG
	    fprintf (stderr, "    processing '%s'\n", this);
#endif
	    newaddrs = 0;
	    err = krb5_os_hostaddr (context, this, &newaddrs);
	    if (err)
		continue;
	    for (i = 0; newaddrs[i]; i++) {
#ifdef DEBUG
		fprintf (stderr, "    %d: family %d", i,
			 newaddrs[i]->addrtype);
		fprintf (stderr, "\n");
#endif
	    }
	    count = i;
#ifdef DEBUG
	    fprintf (stderr, "    %d addresses\n", count);
#endif
	    if (datap->cur_idx + count >= datap->cur_size) {
		krb5_address **bigger;
		bigger = realloc (datap->addr_temp,
				  sizeof (krb5_address *) * (datap->cur_idx + count));
		if (bigger) {
		    datap->addr_temp = bigger;
		    datap->cur_size = datap->cur_idx + count;
		}
	    }
	    for (i = 0; i < count; i++) {
		if (datap->cur_idx < datap->cur_size)
		    datap->addr_temp[datap->cur_idx++] = newaddrs[i];
		else
		    free (newaddrs[i]->contents), free (newaddrs[i]);
	    }
	    free (newaddrs);
	}
    }
    return 0;
}

KRB5_DLLIMP krb5_error_code KRB5_CALLCONV
krb5_os_localaddr(context, addr)
    krb5_context context;
    krb5_address FAR * FAR * FAR *addr;
{
    struct localaddr_data data = { 0 };
    int r;
    krb5_error_code err;

    err = krb5_os_localaddr_profile (context, &data);
    /* ignore err for now */

    r = foreach_localaddr (&data, count_addrs, allocate, add_addr);
    if (r != 0) {
	int i;
	if (data.addr_temp) {
	    for (i = 0; i < data.count; i++)
		krb5_xfree (data.addr_temp[i]);
	    free (data.addr_temp);
	}
	if (data.mem_err)
	    return ENOMEM;
	else
	    return r;
    }

    data.cur_idx++; /* null termination */
    if (data.mem_err)
	return ENOMEM;
    else if (data.cur_idx == data.count)
	*addr = data.addr_temp;
    else {
	/* This can easily happen if we have IPv6 link-local
	   addresses.  Just shorten the array.  */
	*addr = (krb5_address **) realloc (data.addr_temp,
					   (sizeof (krb5_address *)
					    * data.cur_idx));
	if (*addr == 0)
	    /* Okay, shortening failed, but the original should still
	       be intact.  */
	    *addr = data.addr_temp;
    }

#ifdef DEBUG
    {
	int j;
	fprintf (stderr, "addresses:\n");
	for (j = 0; addr[0][j]; j++) {
	    struct sockaddr_storage ss;
	    int err2;
	    char namebuf[NI_MAXHOST];
	    void *addrp = 0;

	    fprintf (stderr, "%2d: ", j);
	    fprintf (stderr, "addrtype %2d, length %2d", addr[0][j]->addrtype,
		     addr[0][j]->length);
	    memset (&ss, 0, sizeof (ss));
	    switch (addr[0][j]->addrtype) {
	    case ADDRTYPE_INET:
	    {
		struct sockaddr_in *sinp = ss2sin (&ss);
		sinp->sin_family = AF_INET;
		addrp = &sinp->sin_addr;
#ifdef HAVE_SA_LEN
		sinp->sin_len = sizeof (struct sockaddr_in);
#endif
		break;
	    }
#ifdef KRB5_USE_INET6
	    case ADDRTYPE_INET6:
	    {
		struct sockaddr_in6 *sin6p = ss2sin6 (&ss);
		sin6p->sin6_family = AF_INET6;
		addrp = &sin6p->sin6_addr;
#ifdef HAVE_SA_LEN
		sin6p->sin6_len = sizeof (struct sockaddr_in6);
#endif
		break;
	    }
#endif
	    default:
		ss2sa(&ss)->sa_family = 0;
		break;
	    }
	    if (addrp)
		memcpy (addrp, addr[0][j]->contents, addr[0][j]->length);
	    err2 = getnameinfo (ss2sa(&ss), socklen (ss2sa (&ss)),
				namebuf, sizeof (namebuf), 0, 0,
				NI_NUMERICHOST);
	    if (err2 == 0)
		fprintf (stderr, ": addr %s\n", namebuf);
	    else
		fprintf (stderr, ": getnameinfo error %d\n", err2);
	}
    }
#endif

    return 0;
}

#endif /* not TESTing */

#else /* Windows/Mac version */

/*
 * Hold on to your lunch!  Backup kludge method of obtaining your
 * local IP address, courtesy of Windows Socket Network Programming,
 * by Robert Quinn
 */
#if defined(_MSDOS) || defined(_WIN32)
static struct hostent *local_addr_fallback_kludge()
{
	static struct hostent	host;
	static SOCKADDR_IN	addr;
	static char *		ip_ptrs[2];
	SOCKET			sock;
	int			size = sizeof(SOCKADDR);
	int			err;

	sock = socket(AF_INET, SOCK_DGRAM, 0);
	if (sock == INVALID_SOCKET)
		return NULL;

	/* connect to arbitrary port and address (NOT loopback) */
	addr.sin_family = AF_INET;
	addr.sin_port = htons(IPPORT_ECHO);
	addr.sin_addr.s_addr = inet_addr("204.137.220.51");

	err = connect(sock, (LPSOCKADDR) &addr, sizeof(SOCKADDR));
	if (err == SOCKET_ERROR)
		return NULL;

	err = getsockname(sock, (LPSOCKADDR) &addr, (int FAR *) size);
	if (err == SOCKET_ERROR)
		return NULL;

	closesocket(sock);

	host.h_name = 0;
	host.h_aliases = 0;
	host.h_addrtype = AF_INET;
	host.h_length = 4;
	host.h_addr_list = ip_ptrs;
	ip_ptrs[0] = (char *) &addr.sin_addr.s_addr;
	ip_ptrs[1] = NULL;

	return &host;
}
#endif

/* No ioctls in winsock so we just assume there is only one networking 
 * card per machine, so gethostent is good enough. 
 */
KRB5_DLLIMP krb5_error_code KRB5_CALLCONV
krb5_os_localaddr (krb5_context context, krb5_address ***addr) {
    char host[64];                              /* Name of local machine */
    struct hostent *hostrec;
    int err, count, i;
    krb5_address ** paddr;

    *addr = 0;
    paddr = 0;
    err = 0;
    
    if (gethostname (host, sizeof(host))) {
        err = SOCKET_ERRNO;
    }

    if (!err) {
	    hostrec = gethostbyname (host);
	    if (hostrec == NULL) {
		    err = SOCKET_ERRNO;
	    }
    }

    if (err) {
	    hostrec = local_addr_fallback_kludge();
	    if (!hostrec)
		    return err;
		else
			err = 0;  /* otherwise we will die at cleanup */
    }

    for (count = 0; hostrec->h_addr_list[count]; count++);


    paddr = (krb5_address **)malloc(sizeof(krb5_address *) * (count+1));
    if (!paddr) {
        err = ENOMEM;
        goto cleanup;
    }

    memset(paddr, 0, sizeof(krb5_address *) * (count+1));

    for (i = 0; i < count; i++)
    {
        paddr[i] = (krb5_address *)malloc(sizeof(krb5_address));
        if (paddr[i] == NULL) {
            err = ENOMEM;
            goto cleanup;
        }

        paddr[i]->magic = KV5M_ADDRESS;
        paddr[i]->addrtype = hostrec->h_addrtype;
        paddr[i]->length = hostrec->h_length;
        paddr[i]->contents = (unsigned char *)malloc(paddr[i]->length);
        if (!paddr[i]->contents) {
            err = ENOMEM;
            goto cleanup;
        }
        memcpy(paddr[i]->contents,
               hostrec->h_addr_list[i],
               paddr[i]->length);
    }

 cleanup:
    if (err) {
        if (paddr) {
            for (i = 0; i < count; i++)
            {
                if (paddr[i]) {
                    if (paddr[i]->contents)
                        free(paddr[i]->contents);
                    free(paddr[i]);
                }
            }
            free(paddr);
        }
    }
    else
        *addr = paddr;

    return(err);
}
#endif