lib/libc/net/name6.c: New file

netshell01 needed the following symbols:
  - getipnodebyaddr
  - getipnodebyaddr
  - getipnodebyname

3 files changed, 1125 insertions, 8 deletions

diff --git a/freebsd-userspace/Makefile b/freebsd-userspace/Makefile
index 74726882..695281b6 100644
--- a/freebsd-userspace/Makefile
+++ b/freebsd-userspace/Makefile
@@ -4,16 +4,17 @@ include $(RTEMS_MAKEFILE_PATH)/Makefile.inc
 include $(RTEMS_CUSTOM)
 include $(PROJECT_ROOT)/make/leaf.cfg
 
-CFLAGS += -I include 
-CFLAGS += -I rtems/include 
-CFLAGS += -I lib/libc/include 
-CFLAGS += -I lib/netgraph
-CFLAGS += -I sys
-CFLAGS += -I local 
+CFLAGS += -Iinclude 
+CFLAGS += -Irtems/include 
+CFLAGS += -Ilib/libc/include 
+CFLAGS += -Ilib/libc/resolv 
+CFLAGS += -Ilib/netgraph
+CFLAGS += -Isys
+CFLAGS += -Ilocal 
 # XXX hack to find rpc
-CFLAGS += -I ../services/librpc/include 
+CFLAGS += -I../services/librpc/include 
 
-CFLAGS += -I $(INSTALL_BASE)/include
+CFLAGS += -I$(INSTALL_BASE)/include
 
 CFLAGS += -w 
 CFLAGS += -std=gnu99
@@ -64,6 +65,7 @@ C_FILES += lib/libc/net/if_indextoname.c
 C_FILES += lib/libc/net/if_nameindex.c
 C_FILES += lib/libc/net/linkaddr.c
 C_FILES += lib/libc/net/map_v4v6.c
+C_FILES += lib/libc/net/name6.c
 C_FILES += lib/libc/net/rcmd.c
 C_FILES += lib/libc/net/recv.c
 C_FILES += lib/libc/net/send.c
diff --git a/freebsd-userspace/from-freebsd.sh b/freebsd-userspace/from-freebsd.sh
index e2fb85aa..93b71997 100755
--- a/freebsd-userspace/from-freebsd.sh
+++ b/freebsd-userspace/from-freebsd.sh
@@ -207,6 +207,7 @@ lib/libc/net/if_indextoname.c
 lib/libc/net/if_nameindex.c
 lib/libc/net/linkaddr.c
 lib/libc/net/map_v4v6.c
+lib/libc/net/name6.c
 lib/libc/net/rcmd.c
 lib/libc/net/recv.c
 lib/libc/net/send.c
diff --git a/freebsd-userspace/lib/libc/net/name6.c b/freebsd-userspace/lib/libc/net/name6.c
new file mode 100644
index 00000000..d6fb6782
--- /dev/null
+++ b/freebsd-userspace/lib/libc/net/name6.c
@@ -0,0 +1,1114 @@
+#include "port_before.h"
+/*	$KAME: name6.c,v 1.25 2000/06/26 16:44:40 itojun Exp $	*/
+
+/*
+ * Copyright (C) 1995, 1996, 1997, 1998, and 1999 WIDE Project.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project 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 BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+/*
+ * ++Copyright++ 1985, 1988, 1993
+ * -
+ * Copyright (c) 1985, 1988, 1993
+ *    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 the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ * 	This product includes software developed by the University of
+ * 	California, Berkeley and its contributors.
+ * 4. 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 BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ * -
+ * Portions Copyright (c) 1993 by Digital Equipment Corporation.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies, and that
+ * the name of Digital Equipment Corporation not be used in advertising or
+ * publicity pertaining to distribution of the document or software without
+ * specific, written prior permission.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
+ * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
+ * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+ * SOFTWARE.
+ * -
+ * --Copyright--
+ */
+
+/*
+ *	Atsushi Onoe <onoe@sm.sony.co.jp>
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "namespace.h"
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <sys/queue.h>
+#include <netinet/in.h>
+#ifdef INET6
+#include <net/if.h>
+#include <net/if_var.h>
+#include <sys/sysctl.h>
+#include <sys/ioctl.h>
+#include <netinet6/in6_var.h>	/* XXX */
+#endif
+
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+
+#include <errno.h>
+#include <netdb.h>
+#include <resolv.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <nsswitch.h>
+#include <unistd.h>
+#include "un-namespace.h"
+#include "netdb_private.h"
+#include "res_private.h"
+
+#ifndef MAXALIASES
+#define	MAXALIASES	10
+#endif
+#ifndef	MAXADDRS
+#define	MAXADDRS	20
+#endif
+#ifndef MAXDNAME
+#define	MAXDNAME	1025
+#endif
+
+#ifdef INET6
+#define	ADDRLEN(af)	((af) == AF_INET6 ? sizeof(struct in6_addr) : \
+					    sizeof(struct in_addr))
+#else
+#define	ADDRLEN(af)	sizeof(struct in_addr)
+#endif
+
+#define	MAPADDR(ab, ina) \
+do {									\
+	memcpy(&(ab)->map_inaddr, ina, sizeof(struct in_addr));		\
+	memset((ab)->map_zero, 0, sizeof((ab)->map_zero));		\
+	memset((ab)->map_one, 0xff, sizeof((ab)->map_one));		\
+} while (0)
+#define	MAPADDRENABLED(flags) \
+	(((flags) & AI_V4MAPPED) || \
+	 (((flags) & AI_V4MAPPED_CFG)))
+
+union inx_addr {
+	struct in_addr	in_addr;
+#ifdef INET6
+	struct in6_addr	in6_addr;
+#endif
+	struct {
+		u_char	mau_zero[10];
+		u_char	mau_one[2];
+		struct in_addr mau_inaddr;
+	}		map_addr_un;
+#define	map_zero	map_addr_un.mau_zero
+#define	map_one		map_addr_un.mau_one
+#define	map_inaddr	map_addr_un.mau_inaddr
+};
+
+struct policyqueue {
+	TAILQ_ENTRY(policyqueue) pc_entry;
+#ifdef INET6
+	struct in6_addrpolicy pc_policy;
+#endif
+};
+TAILQ_HEAD(policyhead, policyqueue);
+
+#define AIO_SRCFLAG_DEPRECATED	0x1
+
+struct hp_order {
+	union {
+		struct sockaddr_storage aiou_ss;
+		struct sockaddr aiou_sa;
+	} aio_src_un;
+#define aio_srcsa aio_src_un.aiou_sa
+	u_int32_t aio_srcflag;
+	int aio_srcscope;
+	int aio_dstscope;
+	struct policyqueue *aio_srcpolicy;
+	struct policyqueue *aio_dstpolicy;
+	union {
+		struct sockaddr_storage aiou_ss;
+		struct sockaddr aiou_sa;
+	} aio_un;
+#define aio_sa aio_un.aiou_sa
+	int aio_matchlen;
+	char *aio_h_addr;
+};
+
+static struct	 hostent *_hpcopy(struct hostent *, int *);
+static struct	 hostent *_hpaddr(int, const char *, void *, int *);
+#ifdef INET6
+static struct	 hostent *_hpmerge(struct hostent *, struct hostent *, int *);
+static struct	 hostent *_hpmapv6(struct hostent *, int *);
+#endif
+static struct	 hostent *_hpsort(struct hostent *, res_state);
+
+static struct	 hostent *_hpreorder(struct hostent *);
+static int	 get_addrselectpolicy(struct policyhead *);
+static void	 free_addrselectpolicy(struct policyhead *);
+static struct	 policyqueue *match_addrselectpolicy(struct sockaddr *,
+	struct policyhead *);
+static void	 set_source(struct hp_order *, struct policyhead *);
+static int	 matchlen(struct sockaddr *, struct sockaddr *);
+static int	 comp_dst(const void *, const void *);
+static int	 gai_addr2scopetype(struct sockaddr *);
+
+/*
+ * Functions defined in RFC2553
+ *	getipnodebyname, getipnodebyaddr, freehostent
+ */
+
+struct hostent *
+getipnodebyname(const char *name, int af, int flags, int *errp)
+{
+	struct hostent *hp;
+	union inx_addr addrbuf;
+	res_state statp;
+	u_long options;
+
+	switch (af) {
+	case AF_INET:
+#ifdef INET6
+	case AF_INET6:
+#endif
+		break;
+	default:
+		*errp = NO_RECOVERY;
+		return NULL;
+	}
+
+	if (flags & AI_ADDRCONFIG) {
+		int s;
+
+		if ((s = _socket(af, SOCK_DGRAM, 0)) < 0)
+			return NULL;
+		/*
+		 * TODO:
+		 * Note that implementation dependent test for address
+		 * configuration should be done everytime called
+		 * (or apropriate interval),
+		 * because addresses will be dynamically assigned or deleted.
+		 */
+		_close(s);
+	}
+	
+#ifdef INET6
+	/* special case for literal address */
+	if (inet_pton(AF_INET6, name, &addrbuf) == 1) {
+		if (af != AF_INET6) {
+			*errp = HOST_NOT_FOUND;
+			return NULL;
+		}
+		return _hpaddr(af, name, &addrbuf, errp);
+	}
+#endif
+	if (inet_aton(name, (struct in_addr *)&addrbuf) == 1) {
+		if (af != AF_INET) {
+			if (MAPADDRENABLED(flags)) {
+				MAPADDR(&addrbuf, &addrbuf.in_addr);
+			} else {
+				*errp = HOST_NOT_FOUND;
+				return NULL;
+			}
+		}
+		return _hpaddr(af, name, &addrbuf, errp);
+	}
+
+
+	statp = __res_state();
+	if ((statp->options & RES_INIT) == 0) {
+		if (res_ninit(statp) < 0) {
+			*errp = NETDB_INTERNAL;
+			return NULL;
+		}
+	}
+	
+	options = statp->options;
+	statp->options &= ~RES_USE_INET6;
+	
+	hp = gethostbyname2(name, af);
+	hp = _hpcopy(hp, errp);
+
+#ifdef INET6
+	if (af == AF_INET6 && ((flags & AI_ALL) || hp == NULL) &&
+	    MAPADDRENABLED(flags)) {
+		struct hostent *hp2 = gethostbyname2(name, AF_INET);
+		if (hp == NULL)
+			if (hp2 == NULL)
+				*errp = statp->res_h_errno;
+			else
+				hp = _hpmapv6(hp2, errp);
+		else {
+			if (hp2 && strcmp(hp->h_name, hp2->h_name) == 0) {
+				struct hostent *hpb = hp;
+				hp = _hpmerge(hpb, hp2, errp);
+				freehostent(hpb);
+			}
+		}
+	}
+#endif
+	
+	if (hp == NULL)
+		*errp = statp->res_h_errno;
+	
+	statp->options = options;
+	return _hpreorder(_hpsort(hp, statp));
+}
+
+struct hostent *
+getipnodebyaddr(const void *src, size_t len, int af, int *errp)
+{
+	struct hostent *hp;
+	res_state statp;
+	u_long options;
+	
+#ifdef INET6
+	struct in6_addr addrbuf;
+#else
+	struct in_addr addrbuf;
+#endif
+	
+	switch (af) {
+	case AF_INET:
+		if (len != sizeof(struct in_addr)) {
+			*errp = NO_RECOVERY;
+			return NULL;
+		}
+		if ((long)src & ~(sizeof(struct in_addr) - 1)) {
+			memcpy(&addrbuf, src, len);
+			src = &addrbuf;
+		}
+		if (((struct in_addr *)src)->s_addr == 0)
+			return NULL;
+		break;
+#ifdef INET6
+	case AF_INET6:
+		if (len != sizeof(struct in6_addr)) {
+			*errp = NO_RECOVERY;
+			return NULL;
+		}
+		if ((long)src & ~(sizeof(struct in6_addr) / 2 - 1)) {	/*XXX*/
+			memcpy(&addrbuf, src, len);
+			src = &addrbuf;
+		}
+		if (IN6_IS_ADDR_UNSPECIFIED((struct in6_addr *)src))
+			return NULL;
+		if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)src)
+		||  IN6_IS_ADDR_V4COMPAT((struct in6_addr *)src)) {
+			src = (char *)src +
+			    (sizeof(struct in6_addr) - sizeof(struct in_addr));
+			af = AF_INET;
+			len = sizeof(struct in_addr);
+		}
+		break;
+#endif
+	default:
+		*errp = NO_RECOVERY;
+		return NULL;
+	}
+
+	statp = __res_state();
+	if ((statp->options & RES_INIT) == 0) {
+		if (res_ninit(statp) < 0) {
+			RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
+			return NULL;
+		}
+	}
+	
+	options = statp->options;
+	statp->options &= ~RES_USE_INET6;
+
+	hp = gethostbyaddr(src, len, af);
+	if (hp == NULL)
+		*errp = statp->res_h_errno;
+	
+	statp->options = options;	
+	return (_hpcopy(hp, errp));
+}
+
+void
+freehostent(struct hostent *ptr)
+{
+	free(ptr);
+}
+
+/*
+ * Private utility functions
+ */
+
+/*
+ * _hpcopy: allocate and copy hostent structure
+ */
+static struct hostent *
+_hpcopy(struct hostent *hp, int *errp)
+{
+	struct hostent *nhp;
+	char *cp, **pp;
+	int size, addrsize;
+	int nalias = 0, naddr = 0;
+	int al_off;
+	int i;
+
+	if (hp == NULL)
+		return hp;
+
+	/* count size to be allocated */
+	size = sizeof(struct hostent);
+	if (hp->h_name != NULL)
+		size += strlen(hp->h_name) + 1;
+	if ((pp = hp->h_aliases) != NULL) {
+		for (i = 0; *pp != NULL; i++, pp++) {
+			if (**pp != '\0') {
+				size += strlen(*pp) + 1;
+				nalias++;
+			}
+		}
+	}
+	/* adjust alignment */
+	size = ALIGN(size);
+	al_off = size;
+	size += sizeof(char *) * (nalias + 1);
+	addrsize = ALIGN(hp->h_length);
+	if ((pp = hp->h_addr_list) != NULL) {
+		while (*pp++ != NULL)
+			naddr++;
+	}
+	size += addrsize * naddr;
+	size += sizeof(char *) * (naddr + 1);
+
+	/* copy */
+	if ((nhp = (struct hostent *)malloc(size)) == NULL) {
+		*errp = TRY_AGAIN;
+		return NULL;
+	}
+	cp = (char *)&nhp[1];
+	if (hp->h_name != NULL) {
+		nhp->h_name = cp;
+		strcpy(cp, hp->h_name);
+		cp += strlen(cp) + 1;
+	} else
+		nhp->h_name = NULL;
+	nhp->h_aliases = (char **)((char *)nhp + al_off);
+	if ((pp = hp->h_aliases) != NULL) {
+		for (i = 0; *pp != NULL; pp++) {
+			if (**pp != '\0') {
+				nhp->h_aliases[i++] = cp;
+				strcpy(cp, *pp);
+				cp += strlen(cp) + 1;
+			}
+		}
+	}
+	nhp->h_aliases[nalias] = NULL;
+	cp = (char *)&nhp->h_aliases[nalias + 1];
+	nhp->h_addrtype = hp->h_addrtype;
+	nhp->h_length = hp->h_length;
+	nhp->h_addr_list = (char **)cp;
+	if ((pp = hp->h_addr_list) != NULL) {
+		cp = (char *)&nhp->h_addr_list[naddr + 1];
+		for (i = 0; *pp != NULL; pp++) {
+			nhp->h_addr_list[i++] = cp;
+			memcpy(cp, *pp, hp->h_length);
+			cp += addrsize;
+		}
+	}
+	nhp->h_addr_list[naddr] = NULL;
+	return nhp;
+}
+
+/*
+ * _hpaddr: construct hostent structure with one address
+ */
+static struct hostent *
+_hpaddr(int af, const char *name, void *addr, int *errp)
+{
+	struct hostent *hp, hpbuf;
+	char *addrs[2];
+
+	hp = &hpbuf;
+	hp->h_name = (char *)name;
+	hp->h_aliases = NULL;
+	hp->h_addrtype = af;
+	hp->h_length = ADDRLEN(af);
+	hp->h_addr_list = addrs;
+	addrs[0] = (char *)addr;
+	addrs[1] = NULL;
+	return (_hpcopy(hp, errp));
+}
+
+#ifdef INET6
+/*
+ * _hpmerge: merge 2 hostent structure, arguments will be freed
+ */
+static struct hostent *
+_hpmerge(struct hostent *hp1, struct hostent *hp2, int *errp)
+{
+	int i, j;
+	int naddr, nalias;
+	char **pp;
+	struct hostent *hp, hpbuf;
+	char *aliases[MAXALIASES + 1], *addrs[MAXADDRS + 1];
+	union inx_addr addrbuf[MAXADDRS];
+
+	if (hp1 == NULL)
+		return _hpcopy(hp2, errp);
+	if (hp2 == NULL)
+		return _hpcopy(hp1, errp);
+
+#define	HP(i)	(i == 1 ? hp1 : hp2)
+	hp = &hpbuf;
+	hp->h_name = (hp1->h_name != NULL ? hp1->h_name : hp2->h_name);
+	hp->h_aliases = aliases;
+	nalias = 0;
+	for (i = 1; i <= 2; i++) {
+		if ((pp = HP(i)->h_aliases) == NULL)
+			continue;
+		for (; nalias < MAXALIASES && *pp != NULL; pp++) {
+			/* check duplicates */
+			for (j = 0; j < nalias; j++)
+				if (strcasecmp(*pp, aliases[j]) == 0)
+					break;
+			if (j == nalias)
+				aliases[nalias++] = *pp;
+		}
+	}
+	aliases[nalias] = NULL;
+	if (hp1->h_length != hp2->h_length) {
+		hp->h_addrtype = AF_INET6;
+		hp->h_length = sizeof(struct in6_addr);
+	} else {
+		hp->h_addrtype = hp1->h_addrtype;
+		hp->h_length = hp1->h_length;
+	}
+
+	hp->h_addr_list = addrs;
+	naddr = 0;
+	for (i = 1; i <= 2; i++) {
+		if ((pp = HP(i)->h_addr_list) == NULL)
+			continue;
+		if (HP(i)->h_length == hp->h_length) {
+			while (naddr < MAXADDRS && *pp != NULL)
+				addrs[naddr++] = *pp++;
+		} else {
+			/* copy IPv4 addr as mapped IPv6 addr */
+			while (naddr < MAXADDRS && *pp != NULL) {
+				MAPADDR(&addrbuf[naddr], *pp++);
+				addrs[naddr] = (char *)&addrbuf[naddr];
+				naddr++;
+			}
+		}
+	}
+	addrs[naddr] = NULL;
+	return (_hpcopy(hp, errp));
+}
+#endif
+
+/*
+ * _hpmapv6: convert IPv4 hostent into IPv4-mapped IPv6 addresses
+ */
+#ifdef INET6
+static struct hostent *
+_hpmapv6(struct hostent *hp, int *errp)
+{
+	struct hostent hp6;
+
+	if (hp == NULL)
+		return NULL;
+	if (hp->h_addrtype == AF_INET6)
+		return _hpcopy(hp, errp);
+
+	memset(&hp6, 0, sizeof(struct hostent));
+	hp6.h_addrtype = AF_INET6;
+	hp6.h_length = sizeof(struct in6_addr);
+	return _hpmerge(&hp6, hp, errp);
+}
+#endif
+
+/*
+ * _hpsort: sort address by sortlist
+ */
+static struct hostent *
+_hpsort(struct hostent *hp, res_state statp)
+{
+	int i, j, n;
+	u_char *ap, *sp, *mp, **pp;
+	char t;
+	char order[MAXADDRS];
+	int nsort = statp->nsort;
+
+	if (hp == NULL || hp->h_addr_list[1] == NULL || nsort == 0)
+		return hp;
+	for (i = 0; (ap = (u_char *)hp->h_addr_list[i]); i++) {
+		for (j = 0; j < nsort; j++) {
+#ifdef INET6
+			if (statp->_u._ext.ext->sort_list[j].af !=
+			    hp->h_addrtype)
+				continue;
+			sp = (u_char *)&statp->_u._ext.ext->sort_list[j].addr;
+			mp = (u_char *)&statp->_u._ext.ext->sort_list[j].mask;
+#else
+			sp = (u_char *)&statp->sort_list[j].addr;
+			mp = (u_char *)&statp->sort_list[j].mask;
+#endif
+			for (n = 0; n < hp->h_length; n++) {
+				if ((ap[n] & mp[n]) != sp[n])
+					break;
+			}
+			if (n == hp->h_length)
+				break;
+		}
+		order[i] = j;
+	}
+	n = i;
+	pp = (u_char **)hp->h_addr_list;
+	for (i = 0; i < n - 1; i++) {
+		for (j = i + 1; j < n; j++) {
+			if (order[i] > order[j]) {
+				ap = pp[i];
+				pp[i] = pp[j];
+				pp[j] = ap;
+				t = order[i];
+				order[i] = order[j];
+				order[j] = t;
+			}
+		}
+	}
+	return hp;
+}
+
+/*
+ * _hpreorder: sort address by default address selection
+ */
+static struct hostent *
+_hpreorder(struct hostent *hp)
+{
+	struct hp_order *aio;
+	int i, n;
+	char *ap;
+	struct sockaddr *sa;
+	struct policyhead policyhead;
+
+	if (hp == NULL)
+		return hp;
+
+	switch (hp->h_addrtype) {
+	case AF_INET:
+#ifdef INET6
+	case AF_INET6:
+#endif
+		break;
+	default:
+		free_addrselectpolicy(&policyhead);
+		return hp;
+	}
+
+	/* count the number of addrinfo elements for sorting. */
+	for (n = 0; hp->h_addr_list[n] != NULL; n++)
+		;
+
+	/*
+	 * If the number is small enough, we can skip the reordering process.
+	 */
+	if (n <= 1)
+		return hp;
+
+	/* allocate a temporary array for sort and initialization of it. */
+	if ((aio = malloc(sizeof(*aio) * n)) == NULL)
+		return hp;	/* give up reordering */
+	memset(aio, 0, sizeof(*aio) * n);
+
+	/* retrieve address selection policy from the kernel */
+	TAILQ_INIT(&policyhead);
+	if (!get_addrselectpolicy(&policyhead)) {
+		/* no policy is installed into kernel, we don't sort. */
+		free(aio);
+		return hp;
+	}
+
+	for (i = 0; i < n; i++) {
+		ap = hp->h_addr_list[i];
+		aio[i].aio_h_addr = ap;
+		sa = &aio[i].aio_sa;
+		switch (hp->h_addrtype) {
+		case AF_INET:
+			sa->sa_family = AF_INET;
+			sa->sa_len = sizeof(struct sockaddr_in);
+			memcpy(&((struct sockaddr_in *)sa)->sin_addr, ap,
+			    sizeof(struct in_addr));
+			break;
+#ifdef INET6
+		case AF_INET6:
+			if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) {
+				sa->sa_family = AF_INET;
+				sa->sa_len = sizeof(struct sockaddr_in);
+				memcpy(&((struct sockaddr_in *)sa)->sin_addr,
+				    &ap[12], sizeof(struct in_addr));
+			} else {
+				sa->sa_family = AF_INET6;
+				sa->sa_len = sizeof(struct sockaddr_in6);
+				memcpy(&((struct sockaddr_in6 *)sa)->sin6_addr,
+				    ap, sizeof(struct in6_addr));
+			}
+			break;
+#endif
+		}
+		aio[i].aio_dstscope = gai_addr2scopetype(sa);
+		aio[i].aio_dstpolicy = match_addrselectpolicy(sa, &policyhead);
+		set_source(&aio[i], &policyhead);
+	}
+
+	/* perform sorting. */
+	qsort(aio, n, sizeof(*aio), comp_dst);
+
+	/* reorder the h_addr_list. */
+	for (i = 0; i < n; i++)
+		hp->h_addr_list[i] = aio[i].aio_h_addr;
+
+	/* cleanup and return */
+	free(aio);
+	free_addrselectpolicy(&policyhead);
+	return hp;
+}
+
+static int
+get_addrselectpolicy(struct policyhead *head)
+{
+#ifdef INET6
+	int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
+	size_t l;
+	char *buf;
+	struct in6_addrpolicy *pol, *ep;
+
+	if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0)
+		return (0);
+	if ((buf = malloc(l)) == NULL)
+		return (0);
+	if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) {
+		free(buf);
+		return (0);
+	}
+
+	ep = (struct in6_addrpolicy *)(buf + l);
+	for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) {
+		struct policyqueue *new;
+
+		if ((new = malloc(sizeof(*new))) == NULL) {
+			free_addrselectpolicy(head); /* make the list empty */
+			break;
+		}
+		new->pc_policy = *pol;
+		TAILQ_INSERT_TAIL(head, new, pc_entry);
+	}
+
+	free(buf);
+	return (1);
+#else
+	return (0);
+#endif
+}
+
+static void
+free_addrselectpolicy(struct policyhead *head)
+{
+	struct policyqueue *ent, *nent;
+
+	for (ent = TAILQ_FIRST(head); ent; ent = nent) {
+		nent = TAILQ_NEXT(ent, pc_entry);
+		TAILQ_REMOVE(head, ent, pc_entry);
+		free(ent);
+	}
+}
+
+static struct policyqueue *
+match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
+{
+#ifdef INET6
+	struct policyqueue *ent, *bestent = NULL;
+	struct in6_addrpolicy *pol;
+	int matchlen, bestmatchlen = -1;
+	u_char *mp, *ep, *k, *p, m;
+	struct sockaddr_in6 key;
+
+	switch(addr->sa_family) {
+	case AF_INET6:
+		key = *(struct sockaddr_in6 *)addr;
+		break;
+	case AF_INET:
+		/* convert the address into IPv4-mapped IPv6 address. */
+		memset(&key, 0, sizeof(key));
+		key.sin6_family = AF_INET6;
+		key.sin6_len = sizeof(key);
+		key.sin6_addr.s6_addr[10] = 0xff;
+		key.sin6_addr.s6_addr[11] = 0xff;
+		memcpy(&key.sin6_addr.s6_addr[12],
+		       &((struct sockaddr_in *)addr)->sin_addr, 4);
+		break;
+	default:
+		return(NULL);
+	}
+
+	for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
+		pol = &ent->pc_policy;
+		matchlen = 0;
+
+		mp = (u_char *)&pol->addrmask.sin6_addr;
+		ep = mp + 16;	/* XXX: scope field? */
+		k = (u_char *)&key.sin6_addr;
+		p = (u_char *)&pol->addr.sin6_addr;
+		for (; mp < ep && *mp; mp++, k++, p++) {
+			m = *mp;
+			if ((*k & m) != *p)
+				goto next; /* not match */
+			if (m == 0xff) /* short cut for a typical case */
+				matchlen += 8;
+			else {
+				while (m >= 0x80) {
+					matchlen++;
+					m <<= 1;
+				}
+			}
+		}
+
+		/* matched.  check if this is better than the current best. */
+		if (matchlen > bestmatchlen) {
+			bestent = ent;
+			bestmatchlen = matchlen;
+		}
+
+	  next:
+		continue;
+	}
+
+	return(bestent);
+#else
+	return(NULL);
+#endif
+
+}
+
+static void
+set_source(struct hp_order *aio, struct policyhead *ph)
+{
+	struct sockaddr_storage ss = aio->aio_un.aiou_ss;
+	socklen_t srclen;
+	int s;
+
+	/* set unspec ("no source is available"), just in case */
+	aio->aio_srcsa.sa_family = AF_UNSPEC;
+	aio->aio_srcscope = -1;
+
+	switch(ss.ss_family) {
+	case AF_INET:
+		((struct sockaddr_in *)&ss)->sin_port = htons(1);
+		break;
+#ifdef INET6
+	case AF_INET6:
+		((struct sockaddr_in6 *)&ss)->sin6_port = htons(1);
+		break;
+#endif
+	default:		/* ignore unsupported AFs explicitly */
+		return;
+	}
+
+	/* open a socket to get the source address for the given dst */
+	if ((s = _socket(ss.ss_family, SOCK_DGRAM, IPPROTO_UDP)) < 0)
+		return;		/* give up */
+	if (_connect(s, (struct sockaddr *)&ss, ss.ss_len) < 0)
+		goto cleanup;
+	srclen = ss.ss_len;
+	if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
+		aio->aio_srcsa.sa_family = AF_UNSPEC;
+		goto cleanup;
+	}
+	aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
+	aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
+	aio->aio_matchlen = matchlen(&aio->aio_srcsa, (struct sockaddr *)&ss);
+#ifdef INET6
+	if (ss.ss_family == AF_INET6) {
+		struct in6_ifreq ifr6;
+		u_int32_t flags6;
+
+		/* XXX: interface name should not be hardcoded */
+		strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name));
+		memset(&ifr6, 0, sizeof(ifr6));
+		memcpy(&ifr6.ifr_addr, &ss, ss.ss_len);
+		if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
+			flags6 = ifr6.ifr_ifru.ifru_flags6;
+			if ((flags6 & IN6_IFF_DEPRECATED))
+				aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
+		}
+	}
+#endif
+
+  cleanup:
+	_close(s);
+	return;
+}
+
+static int
+matchlen(struct sockaddr *src, struct sockaddr *dst)
+{
+	int match = 0;
+	u_char *s, *d;
+	u_char *lim, r;
+	int addrlen;
+
+	switch (src->sa_family) {
+#ifdef INET6
+	case AF_INET6:
+		s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr;
+		d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr;
+		addrlen = sizeof(struct in6_addr);
+		lim = s + addrlen;
+		break;
+#endif
+	case AF_INET:
+		s = (u_char *)&((struct sockaddr_in *)src)->sin_addr;
+		d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr;
+		addrlen = sizeof(struct in_addr);
+		lim = s + addrlen;
+		break;
+	default:
+		return(0);
+	}
+
+	while (s < lim)
+		if ((r = (*d++ ^ *s++)) != 0) {
+			while (r < addrlen * 8) {
+				match++;
+				r <<= 1;
+			}
+			break;
+		} else
+			match += 8;
+	return(match);
+}
+
+static int
+comp_dst(const void *arg1, const void *arg2)
+{
+	const struct hp_order *dst1 = arg1, *dst2 = arg2;
+
+	/*
+	 * Rule 1: Avoid unusable destinations.
+	 * XXX: we currently do not consider if an appropriate route exists.
+	 */
+	if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
+	    dst2->aio_srcsa.sa_family == AF_UNSPEC) {
+		return(-1);
+	}
+	if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
+	    dst2->aio_srcsa.sa_family != AF_UNSPEC) {
+		return(1);
+	}
+
+	/* Rule 2: Prefer matching scope. */
+	if (dst1->aio_dstscope == dst1->aio_srcscope &&
+	    dst2->aio_dstscope != dst2->aio_srcscope) {
+		return(-1);
+	}
+	if (dst1->aio_dstscope != dst1->aio_srcscope &&
+	    dst2->aio_dstscope == dst2->aio_srcscope) {
+		return(1);
+	}
+
+	/* Rule 3: Avoid deprecated addresses. */
+	if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
+	    dst2->aio_srcsa.sa_family != AF_UNSPEC) {
+		if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
+		    (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
+			return(-1);
+		}
+		if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
+		    !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
+			return(1);
+		}
+	}
+
+	/* Rule 4: Prefer home addresses. */
+	/* XXX: not implemented yet */
+
+	/* Rule 5: Prefer matching label. */
+#ifdef INET6
+	if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
+	    dst1->aio_srcpolicy->pc_policy.label ==
+	    dst1->aio_dstpolicy->pc_policy.label &&
+	    (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
+	     dst2->aio_srcpolicy->pc_policy.label !=
+	     dst2->aio_dstpolicy->pc_policy.label)) {
+		return(-1);
+	}
+	if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
+	    dst2->aio_srcpolicy->pc_policy.label ==
+	    dst2->aio_dstpolicy->pc_policy.label &&
+	    (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
+	     dst1->aio_srcpolicy->pc_policy.label !=
+	     dst1->aio_dstpolicy->pc_policy.label)) {
+		return(1);
+	}
+#endif
+
+	/* Rule 6: Prefer higher precedence. */
+#ifdef INET6
+	if (dst1->aio_dstpolicy &&
+	    (dst2->aio_dstpolicy == NULL ||
+	     dst1->aio_dstpolicy->pc_policy.preced >
+	     dst2->aio_dstpolicy->pc_policy.preced)) {
+		return(-1);
+	}
+	if (dst2->aio_dstpolicy &&
+	    (dst1->aio_dstpolicy == NULL ||
+	     dst2->aio_dstpolicy->pc_policy.preced >
+	     dst1->aio_dstpolicy->pc_policy.preced)) {
+		return(1);
+	}
+#endif
+
+	/* Rule 7: Prefer native transport. */
+	/* XXX: not implemented yet */
+
+	/* Rule 8: Prefer smaller scope. */
+	if (dst1->aio_dstscope >= 0 &&
+	    dst1->aio_dstscope < dst2->aio_dstscope) {
+		return(-1);
+	}
+	if (dst2->aio_dstscope >= 0 &&
+	    dst2->aio_dstscope < dst1->aio_dstscope) {
+		return(1);
+	}
+
+	/*
+	 * Rule 9: Use longest matching prefix.
+	 * We compare the match length in a same AF only.
+	 */
+	if (dst1->aio_sa.sa_family == dst2->aio_sa.sa_family) {
+		if (dst1->aio_matchlen > dst2->aio_matchlen) {
+			return(-1);
+		}
+		if (dst1->aio_matchlen < dst2->aio_matchlen) {
+			return(1);
+		}
+	}
+
+	/* Rule 10: Otherwise, leave the order unchanged. */
+	return(-1);
+}
+
+/*
+ * Copy from scope.c.
+ * XXX: we should standardize the functions and link them as standard
+ * library.
+ */
+static int
+gai_addr2scopetype(struct sockaddr *sa)
+{
+#ifdef INET6
+	struct sockaddr_in6 *sa6;
+#endif
+	struct sockaddr_in *sa4;
+
+	switch(sa->sa_family) {
+#ifdef INET6
+	case AF_INET6:
+		sa6 = (struct sockaddr_in6 *)sa;
+		if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
+			/* just use the scope field of the multicast address */
+			return(sa6->sin6_addr.s6_addr[2] & 0x0f);
+		}
+		/*
+		 * Unicast addresses: map scope type to corresponding scope
+		 * value defined for multcast addresses.
+		 * XXX: hardcoded scope type values are bad...
+		 */
+		if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
+			return(1); /* node local scope */
+		if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
+			return(2); /* link-local scope */
+		if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
+			return(5); /* site-local scope */
+		return(14);	/* global scope */
+		break;
+#endif
+	case AF_INET:
+		/*
+		 * IPv4 pseudo scoping according to RFC 3484.
+		 */
+		sa4 = (struct sockaddr_in *)sa;
+		/* IPv4 autoconfiguration addresses have link-local scope. */
+		if (((u_char *)&sa4->sin_addr)[0] == 169 &&
+		    ((u_char *)&sa4->sin_addr)[1] == 254)
+			return(2);
+		/* Private addresses have site-local scope. */
+		if (((u_char *)&sa4->sin_addr)[0] == 10 ||
+		    (((u_char *)&sa4->sin_addr)[0] == 172 &&
+		     (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) ||
+		    (((u_char *)&sa4->sin_addr)[0] == 192 &&
+		     ((u_char *)&sa4->sin_addr)[1] == 168))
+			return(14);	/* XXX: It should be 5 unless NAT */
+		/* Loopback addresses have link-local scope. */
+		if (((u_char *)&sa4->sin_addr)[0] == 127)
+			return(2);
+		return(14);
+		break;
+	default:
+		errno = EAFNOSUPPORT; /* is this a good error? */
+		return(-1);
+	}
+}