Flatten bind9 vendor work area

1 files changed, 1253 insertions, 0 deletions

diff --git a/lib/bind/irs/getaddrinfo.c b/lib/bind/irs/getaddrinfo.c
new file mode 100644
index 0000000..1839ba4
--- /dev/null
+++ b/lib/bind/irs/getaddrinfo.c
@@ -0,0 +1,1253 @@
+/*	$KAME: getaddrinfo.c,v 1.14 2001/01/06 09:41:15 jinmei Exp $	*/
+
+/*
+ * Copyright (C) 1995, 1996, 1997, and 1998 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.
+ */
+
+/*! \file
+ * Issues to be discussed:
+ *\li  Thread safe-ness must be checked.
+ *\li  Return values.  There are nonstandard return values defined and used
+ *   in the source code.  This is because RFC2553 is silent about which error
+ *   code must be returned for which situation.
+ *\li  IPv4 classful (shortened) form.  RFC2553 is silent about it.  XNET 5.2
+ *   says to use inet_aton() to convert IPv4 numeric to binary (allows
+ *   classful form as a result).
+ *   current code - disallow classful form for IPv4 (due to use of inet_pton).
+ *\li  freeaddrinfo(NULL).  RFC2553 is silent about it.  XNET 5.2 says it is
+ *   invalid.
+ *   current code - SEGV on freeaddrinfo(NULL)
+ * Note:
+ *\li  We use getipnodebyname() just for thread-safeness.  There's no intent
+ *   to let it do PF_UNSPEC (actually we never pass PF_UNSPEC to
+ *   getipnodebyname().
+ *\li  The code filters out AFs that are not supported by the kernel,
+ *   when globbing NULL hostname (to loopback, or wildcard).  Is it the right
+ *   thing to do?  What is the relationship with post-RFC2553 AI_ADDRCONFIG
+ *   in ai_flags?
+ *\li  (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
+ *   (1) what should we do against numeric hostname (2) what should we do
+ *   against NULL hostname (3) what is AI_ADDRCONFIG itself.  AF not ready?
+ *   non-loopback address configured?  global address configured?
+ * \par Additional Issue:
+ *  To avoid search order issue, we have a big amount of code duplicate
+ *   from gethnamaddr.c and some other places.  The issues that there's no
+ *   lower layer function to lookup "IPv4 or IPv6" record.  Calling
+ *   gethostbyname2 from getaddrinfo will end up in wrong search order, as
+ *   follows:
+ *	\li The code makes use of following calls when asked to resolver with
+ *	  ai_family  = PF_UNSPEC:
+ *\code		getipnodebyname(host, AF_INET6);
+ *		getipnodebyname(host, AF_INET);
+ *\endcode
+ *	\li  This will result in the following queries if the node is configure to
+ *	  prefer /etc/hosts than DNS:
+ *\code
+ *		lookup /etc/hosts for IPv6 address
+ *		lookup DNS for IPv6 address
+ *		lookup /etc/hosts for IPv4 address
+ *		lookup DNS for IPv4 address
+ *\endcode
+ *	  which may not meet people's requirement.
+ *	 \li The right thing to happen is to have underlying layer which does
+ *	  PF_UNSPEC lookup (lookup both) and return chain of addrinfos.
+ *	  This would result in a bit of code duplicate with _dns_ghbyname() and
+ *	  friends.
+ */
+
+#include "port_before.h"
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+
+#include <net/if.h>
+#include <netinet/in.h>
+
+#include <arpa/inet.h>
+#include <arpa/nameser.h>
+
+#include <netdb.h>
+#include <resolv.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <ctype.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+
+#include <stdarg.h>
+
+#include <irs.h>
+#include <isc/assertions.h>
+
+#include "port_after.h"
+
+#include "irs_data.h"
+
+#define SUCCESS 0
+#define ANY 0
+#define YES 1
+#define NO  0
+
+static const char in_addrany[] = { 0, 0, 0, 0 };
+static const char in6_addrany[] = {
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+static const char in_loopback[] = { 127, 0, 0, 1 };
+static const char in6_loopback[] = {
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
+};
+
+static const struct afd {
+	int a_af;
+	int a_addrlen;
+	int a_socklen;
+	int a_off;
+	const char *a_addrany;
+	const char *a_loopback;
+	int a_scoped;
+} afdl [] = {
+	{PF_INET6, sizeof(struct in6_addr),
+	 sizeof(struct sockaddr_in6),
+	 offsetof(struct sockaddr_in6, sin6_addr),
+	 in6_addrany, in6_loopback, 1},
+	{PF_INET, sizeof(struct in_addr),
+	 sizeof(struct sockaddr_in),
+	 offsetof(struct sockaddr_in, sin_addr),
+	 in_addrany, in_loopback, 0},
+	{0, 0, 0, 0, NULL, NULL, 0},
+};
+
+struct explore {
+	int e_af;
+	int e_socktype;
+	int e_protocol;
+	const char *e_protostr;
+	int e_wild;
+#define WILD_AF(ex)		((ex)->e_wild & 0x01)
+#define WILD_SOCKTYPE(ex)	((ex)->e_wild & 0x02)
+#define WILD_PROTOCOL(ex)	((ex)->e_wild & 0x04)
+};
+
+static const struct explore explore[] = {
+#if 0
+	{ PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
+#endif
+	{ PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
+	{ PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
+	{ PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
+	{ PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
+	{ PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
+	{ PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
+	{ -1, 0, 0, NULL, 0 },
+};
+
+#define PTON_MAX	16
+
+static int str_isnumber __P((const char *));
+static int explore_fqdn __P((const struct addrinfo *, const char *,
+	const char *, struct addrinfo **));
+static int explore_copy __P((const struct addrinfo *, const struct addrinfo *,
+	struct addrinfo **));
+static int explore_null __P((const struct addrinfo *,
+	const char *, struct addrinfo **));
+static int explore_numeric __P((const struct addrinfo *, const char *,
+	const char *, struct addrinfo **));
+static int explore_numeric_scope __P((const struct addrinfo *, const char *,
+	const char *, struct addrinfo **));
+static int get_canonname __P((const struct addrinfo *,
+	struct addrinfo *, const char *));
+static struct addrinfo *get_ai __P((const struct addrinfo *,
+	const struct afd *, const char *));
+static struct addrinfo *copy_ai __P((const struct addrinfo *));
+static int get_portmatch __P((const struct addrinfo *, const char *));
+static int get_port __P((const struct addrinfo *, const char *, int));
+static const struct afd *find_afd __P((int));
+static int addrconfig __P((int));
+static int ip6_str2scopeid __P((char *, struct sockaddr_in6 *,
+				u_int32_t *scopeidp));
+static struct net_data *init __P((void));
+
+struct addrinfo *hostent2addrinfo __P((struct hostent *,
+				       const struct addrinfo *));
+struct addrinfo *addr2addrinfo __P((const struct addrinfo *,
+				    const char *));
+
+#if 0
+static const char *ai_errlist[] = {
+	"Success",
+	"Address family for hostname not supported",	/*%< EAI_ADDRFAMILY */
+	"Temporary failure in name resolution",		/*%< EAI_AGAIN */
+	"Invalid value for ai_flags",		       	/*%< EAI_BADFLAGS */
+	"Non-recoverable failure in name resolution", 	/*%< EAI_FAIL */
+	"ai_family not supported",			/*%< EAI_FAMILY */
+	"Memory allocation failure", 			/*%< EAI_MEMORY */
+	"No address associated with hostname", 		/*%< EAI_NODATA */
+	"hostname nor servname provided, or not known",	/*%< EAI_NONAME */
+	"servname not supported for ai_socktype",	/*%< EAI_SERVICE */
+	"ai_socktype not supported", 			/*%< EAI_SOCKTYPE */
+	"System error returned in errno", 		/*%< EAI_SYSTEM */
+	"Invalid value for hints",			/*%< EAI_BADHINTS */
+	"Resolved protocol is unknown",			/*%< EAI_PROTOCOL */
+	"Unknown error", 				/*%< EAI_MAX */
+};
+#endif
+
+/* XXX macros that make external reference is BAD. */
+
+#define GET_AI(ai, afd, addr) \
+do { \
+	/* external reference: pai, error, and label free */ \
+	(ai) = get_ai(pai, (afd), (addr)); \
+	if ((ai) == NULL) { \
+		error = EAI_MEMORY; \
+		goto free; \
+	} \
+} while (/*CONSTCOND*/0)
+
+#define GET_PORT(ai, serv) \
+do { \
+	/* external reference: error and label free */ \
+	error = get_port((ai), (serv), 0); \
+	if (error != 0) \
+		goto free; \
+} while (/*CONSTCOND*/0)
+
+#define GET_CANONNAME(ai, str) \
+do { \
+	/* external reference: pai, error and label free */ \
+	error = get_canonname(pai, (ai), (str)); \
+	if (error != 0) \
+		goto free; \
+} while (/*CONSTCOND*/0)
+
+#ifndef SOLARIS2
+#define SETERROR(err) \
+do { \
+	/* external reference: error, and label bad */ \
+	error = (err); \
+	goto bad; \
+	/*NOTREACHED*/ \
+} while (/*CONSTCOND*/0)
+#else
+#define SETERROR(err) \
+do { \
+	/* external reference: error, and label bad */ \
+	error = (err); \
+	if (error == error) \
+		goto bad; \
+} while (/*CONSTCOND*/0)
+#endif
+
+
+#define MATCH_FAMILY(x, y, w) \
+	((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
+#define MATCH(x, y, w) \
+	((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
+
+#if 0				/*%< bind8 has its own version */
+char *
+gai_strerror(ecode)
+	int ecode;
+{
+	if (ecode < 0 || ecode > EAI_MAX)
+		ecode = EAI_MAX;
+	return ai_errlist[ecode];
+}
+#endif
+
+void
+freeaddrinfo(ai)
+	struct addrinfo *ai;
+{
+	struct addrinfo *next;
+
+	do {
+		next = ai->ai_next;
+		if (ai->ai_canonname)
+			free(ai->ai_canonname);
+		/* no need to free(ai->ai_addr) */
+		free(ai);
+		ai = next;
+	} while (ai);
+}
+
+static int
+str_isnumber(p)
+	const char *p;
+{
+	char *ep;
+
+	if (*p == '\0')
+		return NO;
+	ep = NULL;
+	errno = 0;
+	(void)strtoul(p, &ep, 10);
+	if (errno == 0 && ep && *ep == '\0')
+		return YES;
+	else
+		return NO;
+}
+
+int
+getaddrinfo(hostname, servname, hints, res)
+	const char *hostname, *servname;
+	const struct addrinfo *hints;
+	struct addrinfo **res;
+{
+	struct addrinfo sentinel;
+	struct addrinfo *cur;
+	int error = 0;
+	struct addrinfo ai, ai0, *afai = NULL;
+	struct addrinfo *pai;
+	const struct explore *ex;
+
+	memset(&sentinel, 0, sizeof(sentinel));
+	cur = &sentinel;
+	pai = &ai;
+	pai->ai_flags = 0;
+	pai->ai_family = PF_UNSPEC;
+	pai->ai_socktype = ANY;
+	pai->ai_protocol = ANY;
+#if defined(sun) && defined(_SOCKLEN_T) && defined(__sparcv9)
+	/*
+	 * clear _ai_pad to preserve binary
+	 * compatibility with previously compiled 64-bit
+	 * applications in a pre-SUSv3 environment by
+	 * guaranteeing the upper 32-bits are empty.
+	 */
+	pai->_ai_pad = 0;
+#endif
+	pai->ai_addrlen = 0;
+	pai->ai_canonname = NULL;
+	pai->ai_addr = NULL;
+	pai->ai_next = NULL;
+
+	if (hostname == NULL && servname == NULL)
+		return EAI_NONAME;
+	if (hints) {
+		/* error check for hints */
+		if (hints->ai_addrlen || hints->ai_canonname ||
+		    hints->ai_addr || hints->ai_next)
+			SETERROR(EAI_BADHINTS); /*%< xxx */
+		if (hints->ai_flags & ~AI_MASK)
+			SETERROR(EAI_BADFLAGS);
+		switch (hints->ai_family) {
+		case PF_UNSPEC:
+		case PF_INET:
+		case PF_INET6:
+			break;
+		default:
+			SETERROR(EAI_FAMILY);
+		}
+		memcpy(pai, hints, sizeof(*pai));
+
+#if defined(sun) && defined(_SOCKLEN_T) && defined(__sparcv9)
+		/*
+		 * We need to clear _ai_pad to preserve binary
+		 * compatibility.  See prior comment.
+		 */
+		pai->_ai_pad = 0;
+#endif
+		/*
+		 * if both socktype/protocol are specified, check if they
+		 * are meaningful combination.
+		 */
+		if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
+			for (ex = explore; ex->e_af >= 0; ex++) {
+				if (pai->ai_family != ex->e_af)
+					continue;
+				if (ex->e_socktype == ANY)
+					continue;
+				if (ex->e_protocol == ANY)
+					continue;
+				if (pai->ai_socktype == ex->e_socktype &&
+				    pai->ai_protocol != ex->e_protocol) {
+					SETERROR(EAI_BADHINTS);
+				}
+			}
+		}
+	}
+
+	/*
+	 * post-2553: AI_ALL and AI_V4MAPPED are effective only against
+	 * AF_INET6 query.  They needs to be ignored if specified in other
+	 * occassions.
+	 */
+	switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) {
+	case AI_V4MAPPED:
+	case AI_ALL | AI_V4MAPPED:
+		if (pai->ai_family != AF_INET6)
+			pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
+		break;
+	case AI_ALL:
+#if 1
+		/* illegal */
+		SETERROR(EAI_BADFLAGS);
+#else
+		pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
+		break;
+#endif
+	}
+
+	/*
+	 * check for special cases.  (1) numeric servname is disallowed if
+	 * socktype/protocol are left unspecified. (2) servname is disallowed
+	 * for raw and other inet{,6} sockets.
+	 */
+	if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
+#ifdef PF_INET6
+	 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
+#endif
+	    ) {
+		ai0 = *pai;	/* backup *pai */
+
+		if (pai->ai_family == PF_UNSPEC) {
+#ifdef PF_INET6
+			pai->ai_family = PF_INET6;
+#else
+			pai->ai_family = PF_INET;
+#endif
+		}
+		error = get_portmatch(pai, servname);
+		if (error)
+			SETERROR(error);
+
+		*pai = ai0;
+	}
+
+	ai0 = *pai;
+
+	/* NULL hostname, or numeric hostname */
+	for (ex = explore; ex->e_af >= 0; ex++) {
+		*pai = ai0;
+
+		if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
+			continue;
+		if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
+			continue;
+		if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
+			continue;
+
+		if (pai->ai_family == PF_UNSPEC)
+			pai->ai_family = ex->e_af;
+		if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
+			pai->ai_socktype = ex->e_socktype;
+		if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
+			pai->ai_protocol = ex->e_protocol;
+
+		/*
+		 * if the servname does not match socktype/protocol, ignore it.
+		 */
+		if (get_portmatch(pai, servname) != 0)
+			continue;
+
+		if (hostname == NULL) {
+			/*
+			 * filter out AFs that are not supported by the kernel
+			 * XXX errno?
+			 */
+			if (!addrconfig(pai->ai_family))
+				continue;
+			error = explore_null(pai, servname, &cur->ai_next);
+		} else
+			error = explore_numeric_scope(pai, hostname, servname,
+			    &cur->ai_next);
+
+		if (error)
+			goto free;
+
+		while (cur && cur->ai_next)
+			cur = cur->ai_next;
+	}
+
+	/*
+	 * XXX
+	 * If numreic representation of AF1 can be interpreted as FQDN
+	 * representation of AF2, we need to think again about the code below.
+	 */
+	if (sentinel.ai_next)
+		goto good;
+
+	if (pai->ai_flags & AI_NUMERICHOST)
+		SETERROR(EAI_NONAME);
+	if (hostname == NULL)
+		SETERROR(EAI_NONAME);
+
+	/*
+	 * hostname as alphabetical name.
+	 * We'll make sure that
+	 * - if returning addrinfo list is empty, return non-zero error
+	 *   value (already known one or EAI_NONAME).
+	 * - otherwise, 
+	 *   + if we haven't had any errors, return 0 (i.e. success).
+	 *   + if we've had an error, free the list and return the error.
+	 * without any assumption on the behavior of explore_fqdn().
+	 */
+
+	/* first, try to query DNS for all possible address families. */
+	*pai = ai0;
+	error = explore_fqdn(pai, hostname, servname, &afai);
+	if (error) {
+		if (afai != NULL)
+			freeaddrinfo(afai);
+		goto free;
+	}
+	if (afai == NULL) {
+		error = EAI_NONAME; /*%< we've had no errors. */
+		goto free;
+	}
+
+	/*
+	 * we would like to prefer AF_INET6 than AF_INET, so we'll make an
+	 * outer loop by AFs.
+	 */
+	for (ex = explore; ex->e_af >= 0; ex++) {
+		*pai = ai0;
+
+		if (pai->ai_family == PF_UNSPEC)
+			pai->ai_family = ex->e_af;
+
+		if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
+			continue;
+		if (!MATCH(pai->ai_socktype, ex->e_socktype,
+			   WILD_SOCKTYPE(ex))) {
+			continue;
+		}
+		if (!MATCH(pai->ai_protocol, ex->e_protocol,
+			   WILD_PROTOCOL(ex))) {
+			continue;
+		}
+
+#ifdef AI_ADDRCONFIG
+		/*
+		 * If AI_ADDRCONFIG is specified, check if we are
+		 * expected to return the address family or not.
+		 */
+		if ((pai->ai_flags & AI_ADDRCONFIG) != 0 &&
+		    !addrconfig(pai->ai_family))
+			continue;
+#endif
+
+		if (pai->ai_family == PF_UNSPEC)
+			pai->ai_family = ex->e_af;
+		if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
+			pai->ai_socktype = ex->e_socktype;
+		if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
+			pai->ai_protocol = ex->e_protocol;
+
+		/*
+		 * if the servname does not match socktype/protocol, ignore it.
+		 */
+		if (get_portmatch(pai, servname) != 0)
+			continue;
+
+		if ((error = explore_copy(pai, afai, &cur->ai_next)) != 0) {
+			freeaddrinfo(afai);
+			goto free;
+		}
+
+		while (cur && cur->ai_next)
+			cur = cur->ai_next;
+	}
+
+	freeaddrinfo(afai);	/*%< afai must not be NULL at this point. */
+
+	if (sentinel.ai_next) {
+good:
+		*res = sentinel.ai_next;
+		return(SUCCESS);
+	} else {
+		/*
+		 * All the process succeeded, but we've had an empty list. 
+		 * This can happen if the given hints do not match our
+		 * candidates.
+		 */
+		error = EAI_NONAME;
+	}
+
+free:
+bad:
+	if (sentinel.ai_next)
+		freeaddrinfo(sentinel.ai_next);
+	*res = NULL;
+	return(error);
+}
+
+/*%
+ * FQDN hostname, DNS lookup
+ */
+static int
+explore_fqdn(pai, hostname, servname, res)
+	const struct addrinfo *pai;
+	const char *hostname;
+	const char *servname;
+	struct addrinfo **res;
+{
+	struct addrinfo *result;
+	struct addrinfo *cur;
+	struct net_data *net_data = init();
+	struct irs_ho *ho;
+	int error = 0;
+	char tmp[NS_MAXDNAME];
+	const char *cp;
+
+	INSIST(res != NULL && *res == NULL);
+
+	/*
+	 * if the servname does not match socktype/protocol, ignore it.
+	 */
+	if (get_portmatch(pai, servname) != 0)
+		return(0);
+
+	if (!net_data || !(ho = net_data->ho))
+		return(0);
+#if 0				/*%< XXX (notyet) */
+	if (net_data->ho_stayopen && net_data->ho_last &&
+	    net_data->ho_last->h_addrtype == af) {
+		if (ns_samename(name, net_data->ho_last->h_name) == 1)
+			return (net_data->ho_last);
+		for (hap = net_data->ho_last->h_aliases; hap && *hap; hap++)
+			if (ns_samename(name, *hap) == 1)
+				return (net_data->ho_last);
+	}
+#endif
+	if (!strchr(hostname, '.') &&
+	    (cp = res_hostalias(net_data->res, hostname,
+				tmp, sizeof(tmp))))
+		hostname = cp;
+	result = (*ho->addrinfo)(ho, hostname, pai);
+	if (!net_data->ho_stayopen) {
+		(*ho->minimize)(ho);
+	}
+	if (result == NULL) {
+		int e = h_errno;
+
+		switch(e) {
+		case NETDB_INTERNAL:
+			error = EAI_SYSTEM;
+			break;
+		case TRY_AGAIN:
+			error = EAI_AGAIN;
+			break;
+		case NO_RECOVERY:
+			error = EAI_FAIL;
+			break;
+		case HOST_NOT_FOUND:
+		case NO_DATA:
+			error = EAI_NONAME;
+			break;
+		default:
+		case NETDB_SUCCESS: /*%< should be impossible... */
+			error = EAI_NONAME;
+			break;
+		}
+		goto free;
+	}
+
+	for (cur = result; cur; cur = cur->ai_next) {
+		GET_PORT(cur, servname); /*%< XXX: redundant lookups... */
+		/* canonname should already be filled. */
+	}
+
+	*res = result;
+
+	return(0);
+
+free:
+	if (result)
+		freeaddrinfo(result);
+	return error;
+}
+
+static int
+explore_copy(pai, src0, res)
+	const struct addrinfo *pai;	/*%< seed */
+	const struct addrinfo *src0;	/*%< source */
+	struct addrinfo **res;
+{
+	int error;
+	struct addrinfo sentinel, *cur;
+	const struct addrinfo *src;
+
+	error = 0;
+	sentinel.ai_next = NULL;
+	cur = &sentinel;
+
+	for (src = src0; src != NULL; src = src->ai_next) {
+		if (src->ai_family != pai->ai_family)
+			continue;
+
+		cur->ai_next = copy_ai(src);
+		if (!cur->ai_next) {
+			error = EAI_MEMORY;
+			goto fail;
+		}
+
+		cur->ai_next->ai_socktype = pai->ai_socktype;
+		cur->ai_next->ai_protocol = pai->ai_protocol;
+		cur = cur->ai_next;
+	}
+
+	*res = sentinel.ai_next;
+	return 0;
+
+fail:
+	freeaddrinfo(sentinel.ai_next);
+	return error;
+}
+
+/*%
+ * hostname == NULL.
+ * passive socket -> anyaddr (0.0.0.0 or ::)
+ * non-passive socket -> localhost (127.0.0.1 or ::1)
+ */
+static int
+explore_null(pai, servname, res)
+	const struct addrinfo *pai;
+	const char *servname;
+	struct addrinfo **res;
+{
+	const struct afd *afd;
+	struct addrinfo *cur;
+	struct addrinfo sentinel;
+	int error;
+
+	*res = NULL;
+	sentinel.ai_next = NULL;
+	cur = &sentinel;
+
+	afd = find_afd(pai->ai_family);
+	if (afd == NULL)
+		return 0;
+
+	if (pai->ai_flags & AI_PASSIVE) {
+		GET_AI(cur->ai_next, afd, afd->a_addrany);
+		/* xxx meaningless?
+		 * GET_CANONNAME(cur->ai_next, "anyaddr");
+		 */
+		GET_PORT(cur->ai_next, servname);
+	} else {
+		GET_AI(cur->ai_next, afd, afd->a_loopback);
+		/* xxx meaningless?
+		 * GET_CANONNAME(cur->ai_next, "localhost");
+		 */
+		GET_PORT(cur->ai_next, servname);
+	}
+	cur = cur->ai_next;
+
+	*res = sentinel.ai_next;
+	return 0;
+
+free:
+	if (sentinel.ai_next)
+		freeaddrinfo(sentinel.ai_next);
+	return error;
+}
+
+/*%
+ * numeric hostname
+ */
+static int
+explore_numeric(pai, hostname, servname, res)
+	const struct addrinfo *pai;
+	const char *hostname;
+	const char *servname;
+	struct addrinfo **res;
+{
+	const struct afd *afd;
+	struct addrinfo *cur;
+	struct addrinfo sentinel;
+	int error;
+	char pton[PTON_MAX];
+
+	*res = NULL;
+	sentinel.ai_next = NULL;
+	cur = &sentinel;
+
+	afd = find_afd(pai->ai_family);
+	if (afd == NULL)
+		return 0;
+
+	switch (afd->a_af) {
+#if 0 /*X/Open spec*/
+	case AF_INET:
+		if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
+			if (pai->ai_family == afd->a_af ||
+			    pai->ai_family == PF_UNSPEC /*?*/) {
+				GET_AI(cur->ai_next, afd, pton);
+				GET_PORT(cur->ai_next, servname);
+				while (cur->ai_next)
+					cur = cur->ai_next;
+			} else
+				SETERROR(EAI_FAMILY);	/*xxx*/
+		}
+		break;
+#endif
+	default:
+		if (inet_pton(afd->a_af, hostname, pton) == 1) {
+			if (pai->ai_family == afd->a_af ||
+			    pai->ai_family == PF_UNSPEC /*?*/) {
+				GET_AI(cur->ai_next, afd, pton);
+				GET_PORT(cur->ai_next, servname);
+				while (cur->ai_next)
+					cur = cur->ai_next;
+			} else
+				SETERROR(EAI_FAMILY);	/*xxx*/
+		}
+		break;
+	}
+
+	*res = sentinel.ai_next;
+	return 0;
+
+free:
+bad:
+	if (sentinel.ai_next)
+		freeaddrinfo(sentinel.ai_next);
+	return error;
+}
+
+/*%
+ * numeric hostname with scope
+ */
+static int
+explore_numeric_scope(pai, hostname, servname, res)
+	const struct addrinfo *pai;
+	const char *hostname;
+	const char *servname;
+	struct addrinfo **res;
+{
+#ifndef SCOPE_DELIMITER
+	return explore_numeric(pai, hostname, servname, res);
+#else
+	const struct afd *afd;
+	struct addrinfo *cur;
+	int error;
+	char *cp, *hostname2 = NULL, *scope, *addr;
+	struct sockaddr_in6 *sin6;
+
+	afd = find_afd(pai->ai_family);
+	if (afd == NULL)
+		return 0;
+
+	if (!afd->a_scoped)
+		return explore_numeric(pai, hostname, servname, res);
+
+	cp = strchr(hostname, SCOPE_DELIMITER);
+	if (cp == NULL)
+		return explore_numeric(pai, hostname, servname, res);
+
+	/*
+	 * Handle special case of <scoped_address><delimiter><scope id>
+	 */
+	hostname2 = strdup(hostname);
+	if (hostname2 == NULL)
+		return EAI_MEMORY;
+	/* terminate at the delimiter */
+	hostname2[cp - hostname] = '\0';
+	addr = hostname2;
+	scope = cp + 1;
+
+	error = explore_numeric(pai, addr, servname, res);
+	if (error == 0) {
+		u_int32_t scopeid = 0;
+
+		for (cur = *res; cur; cur = cur->ai_next) {
+			if (cur->ai_family != AF_INET6)
+				continue;
+			sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
+			if (!ip6_str2scopeid(scope, sin6, &scopeid)) {
+				free(hostname2);
+				return(EAI_NONAME); /*%< XXX: is return OK? */
+			}
+#ifdef HAVE_SIN6_SCOPE_ID
+			sin6->sin6_scope_id = scopeid;
+#endif
+		}
+	}
+
+	free(hostname2);
+
+	return error;
+#endif
+}
+
+static int
+get_canonname(pai, ai, str)
+	const struct addrinfo *pai;
+	struct addrinfo *ai;
+	const char *str;
+{
+	if ((pai->ai_flags & AI_CANONNAME) != 0) {
+		ai->ai_canonname = (char *)malloc(strlen(str) + 1);
+		if (ai->ai_canonname == NULL)
+			return EAI_MEMORY;
+		strcpy(ai->ai_canonname, str);
+	}
+	return 0;
+}
+
+static struct addrinfo *
+get_ai(pai, afd, addr)
+	const struct addrinfo *pai;
+	const struct afd *afd;
+	const char *addr;
+{
+	char *p;
+	struct addrinfo *ai;
+
+	ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
+		+ (afd->a_socklen));
+	if (ai == NULL)
+		return NULL;
+
+	memcpy(ai, pai, sizeof(struct addrinfo));
+	ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
+	memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
+#ifdef HAVE_SA_LEN
+	ai->ai_addr->sa_len = afd->a_socklen;
+#endif
+	ai->ai_addrlen = afd->a_socklen;
+	ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
+	p = (char *)(void *)(ai->ai_addr);
+	memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
+	return ai;
+}
+
+/* XXX need to malloc() the same way we do from other functions! */
+static struct addrinfo *
+copy_ai(pai)
+	const struct addrinfo *pai;
+{
+	struct addrinfo *ai;
+	size_t l;
+
+	l = sizeof(*ai) + pai->ai_addrlen;
+	if ((ai = (struct addrinfo *)malloc(l)) == NULL)
+		return NULL;
+	memset(ai, 0, l);
+	memcpy(ai, pai, sizeof(*ai));
+	ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
+	memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen);
+
+	if (pai->ai_canonname) {
+		l = strlen(pai->ai_canonname) + 1;
+		if ((ai->ai_canonname = malloc(l)) == NULL) {
+			free(ai);
+			return NULL;
+		}
+		strcpy(ai->ai_canonname, pai->ai_canonname);	/* (checked) */
+	} else {
+		/* just to make sure */
+		ai->ai_canonname = NULL;
+	}
+
+	ai->ai_next = NULL;
+
+	return ai;
+}
+
+static int
+get_portmatch(const struct addrinfo *ai, const char *servname) {
+
+	/* get_port does not touch first argument. when matchonly == 1. */
+	/* LINTED const cast */
+	return get_port((const struct addrinfo *)ai, servname, 1);
+}
+
+static int
+get_port(const struct addrinfo *ai, const char *servname, int matchonly) {
+	const char *proto;
+	struct servent *sp;
+	int port;
+	int allownumeric;
+
+	if (servname == NULL)
+		return 0;
+	switch (ai->ai_family) {
+	case AF_INET:
+#ifdef AF_INET6
+	case AF_INET6:
+#endif
+		break;
+	default:
+		return 0;
+	}
+
+	switch (ai->ai_socktype) {
+	case SOCK_RAW:
+		return EAI_SERVICE;
+	case SOCK_DGRAM:
+	case SOCK_STREAM:
+		allownumeric = 1;
+		break;
+	case ANY:
+		switch (ai->ai_family) {
+		case AF_INET:
+#ifdef AF_INET6
+		case AF_INET6:
+#endif
+			allownumeric = 1;
+			break;
+		default:
+			allownumeric = 0;
+			break;
+		}
+		break;
+	default:
+		return EAI_SOCKTYPE;
+	}
+
+	if (str_isnumber(servname)) {
+		if (!allownumeric)
+			return EAI_SERVICE;
+		port = atoi(servname);
+		if (port < 0 || port > 65535)
+			return EAI_SERVICE;
+		port = htons(port);
+	} else {
+		switch (ai->ai_socktype) {
+		case SOCK_DGRAM:
+			proto = "udp";
+			break;
+		case SOCK_STREAM:
+			proto = "tcp";
+			break;
+		default:
+			proto = NULL;
+			break;
+		}
+
+		if ((sp = getservbyname(servname, proto)) == NULL)
+			return EAI_SERVICE;
+		port = sp->s_port;
+	}
+
+	if (!matchonly) {
+		switch (ai->ai_family) {
+		case AF_INET:
+			((struct sockaddr_in *)(void *)
+			    ai->ai_addr)->sin_port = port;
+			break;
+		case AF_INET6:
+			((struct sockaddr_in6 *)(void *)
+			    ai->ai_addr)->sin6_port = port;
+			break;
+		}
+	}
+
+	return 0;
+}
+
+static const struct afd *
+find_afd(af)
+	int af;
+{
+	const struct afd *afd;
+
+	if (af == PF_UNSPEC)
+		return NULL;
+	for (afd = afdl; afd->a_af; afd++) {
+		if (afd->a_af == af)
+			return afd;
+	}
+	return NULL;
+}
+
+/*%
+ * post-2553: AI_ADDRCONFIG check.  if we use getipnodeby* as backend, backend
+ * will take care of it.
+ * the semantics of AI_ADDRCONFIG is not defined well.  we are not sure
+ * if the code is right or not.
+ */
+static int
+addrconfig(af)
+	int af;
+{
+	int s;
+
+	/* XXX errno */
+	s = socket(af, SOCK_DGRAM, 0);
+	if (s < 0) {
+		if (errno != EMFILE)
+			return 0;
+	} else
+		close(s);
+	return 1;
+}
+
+/* convert a string to a scope identifier. XXX: IPv6 specific */
+static int
+ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6,
+		u_int32_t *scopeidp)
+{
+	u_int32_t scopeid;
+	u_long lscopeid;
+	struct in6_addr *a6 = &sin6->sin6_addr;
+	char *ep;
+	
+	/* empty scopeid portion is invalid */
+	if (*scope == '\0')
+		return (0);
+
+#ifdef USE_IFNAMELINKID
+	if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) ||
+	    IN6_IS_ADDR_MC_NODELOCAL(a6)) {
+		/*
+		 * Using interface names as link indices can be allowed
+		 * only when we can assume a one-to-one mappings between
+		 * links and interfaces.  See comments in getnameinfo.c.
+		 */
+		scopeid = if_nametoindex(scope);
+		if (scopeid == 0)
+			goto trynumeric;
+		*scopeidp = scopeid;
+		return (1);
+	}
+#endif
+
+	/* still unclear about literal, allow numeric only - placeholder */
+	if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
+		goto trynumeric;
+	if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
+		goto trynumeric;
+	else
+		goto trynumeric;	/*%< global */
+	/* try to convert to a numeric id as a last resort */
+trynumeric:
+	errno = 0;
+	lscopeid = strtoul(scope, &ep, 10);
+	scopeid = lscopeid & 0xffffffff;
+	if (errno == 0 && ep && *ep == '\0' && scopeid == lscopeid) {
+		*scopeidp = scopeid;
+		return (1);
+	} else
+		return (0);
+}
+
+struct addrinfo *
+hostent2addrinfo(hp, pai)
+	struct hostent *hp;
+	const struct addrinfo *pai;
+{
+	int i, af, error = 0;
+	char **aplist = NULL, *ap;
+	struct addrinfo sentinel, *cur;
+	const struct afd *afd;
+
+	af = hp->h_addrtype;
+	if (pai->ai_family != AF_UNSPEC && af != pai->ai_family)
+		return(NULL);
+
+	afd = find_afd(af);
+	if (afd == NULL)
+		return(NULL);
+
+	aplist = hp->h_addr_list;
+
+	memset(&sentinel, 0, sizeof(sentinel));
+	cur = &sentinel;
+
+	for (i = 0; (ap = aplist[i]) != NULL; i++) {
+#if 0				/*%< the trick seems too much */
+		af = hp->h_addr_list;
+		if (af == AF_INET6 &&
+		    IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) {
+			af = AF_INET;
+			ap = ap + sizeof(struct in6_addr)
+				- sizeof(struct in_addr);
+		}
+		afd = find_afd(af);
+		if (afd == NULL)
+			continue;
+#endif /* 0 */
+
+		GET_AI(cur->ai_next, afd, ap);
+
+		/* GET_PORT(cur->ai_next, servname); */
+		if ((pai->ai_flags & AI_CANONNAME) != 0) {
+			/*
+			 * RFC2553 says that ai_canonname will be set only for
+			 * the first element.  we do it for all the elements,
+			 * just for convenience.
+			 */
+			GET_CANONNAME(cur->ai_next, hp->h_name);
+		}
+		while (cur->ai_next) /*%< no need to loop, actually. */
+			cur = cur->ai_next;
+		continue;
+
+	free:
+		if (cur->ai_next)
+			freeaddrinfo(cur->ai_next);
+		cur->ai_next = NULL;
+		/* continue, without tht pointer CUR advanced. */
+	}
+
+	return(sentinel.ai_next);
+}
+
+struct addrinfo *
+addr2addrinfo(pai, cp)
+	const struct addrinfo *pai;
+	const char *cp;
+{
+	const struct afd *afd;
+
+	afd = find_afd(pai->ai_family);
+	if (afd == NULL)
+		return(NULL);
+
+	return(get_ai(pai, afd, cp));
+}
+
+static struct net_data *
+init()
+{
+	struct net_data *net_data;
+
+	if (!(net_data = net_data_init(NULL)))
+		goto error;
+	if (!net_data->ho) {
+		net_data->ho = (*net_data->irs->ho_map)(net_data->irs);
+		if (!net_data->ho || !net_data->res) {
+error:
+			errno = EIO;
+			if (net_data && net_data->res)
+				RES_SET_H_ERRNO(net_data->res, NETDB_INTERNAL);
+			return (NULL);
+		}
+
+		(*net_data->ho->res_set)(net_data->ho, net_data->res, NULL);
+	}
+
+	return (net_data);
+}