6 files changed, 530 insertions, 154 deletions

diff --git a/lib/libc/net/Makefile.inc b/lib/libc/net/Makefile.inc
index 22c40109b8a2..1d3ab660da73 100644
--- a/lib/libc/net/Makefile.inc
+++ b/lib/libc/net/Makefile.inc
@@ -6,7 +6,7 @@
 
 SRCS+=	addr2ascii.c ascii2addr.c base64.c ether_addr.c getaddrinfo.c \
 	gethostbydns.c gethostbyht.c gethostbynis.c gethostnamadr.c \
-	getnameinfo.c \
+	getifaddrs.c getnameinfo.c \
 	getnetbydns.c getnetbyht.c getnetbynis.c getnetnamadr.c \
 	getproto.c getprotoent.c getprotoname.c getservbyname.c \
 	getservbyport.c getservent.c herror.c inet_addr.c ifname.c \
@@ -28,7 +28,7 @@ CFLAGS+=-DINET6
 
 .if ${LIB} == "c"
 MAN3+=	addr2ascii.3 byteorder.3 ethers.3 getaddrinfo.3 gethostbyname.3 \
-	getipnodebyname.3 \
+	getifaddrs.3 getipnodebyname.3 \
 	getnameinfo.3 getnetent.3 getprotoent.3 getservent.3 if_indextoname.3 \
 	inet.3 inet6_option_space.3 inet6_rthdr_space.3 linkaddr.3 \
 	rcmd.3 resolver.3
@@ -44,6 +44,7 @@ MLINKS+=gethostbyname.3 endhostent.3 gethostbyname.3 gethostbyaddr.3 \
 	gethostbyname.3 gethostbyname2.3 gethostbyname.3 gethostent.3 \
 	gethostbyname.3 herror.3 gethostbyname.3 hstrerror.3 \
 	gethostbyname.3 sethostent.3
+MLINKS+=getifaddrs.3 freeifaddrs.3
 MLINKS+=getipnodebyname.3 getipnodebyaddr.3 getipnodebyname.3 freehostent.3
 MLINKS+=getnetent.3 endnetent.3 getnetent.3 getnetbyaddr.3 \
 	getnetent.3 getnetbyname.3 getnetent.3 setnetent.3
diff --git a/lib/libc/net/getaddrinfo.3 b/lib/libc/net/getaddrinfo.3
index fd4b6d154b13..2e608cd18ae2 100644
--- a/lib/libc/net/getaddrinfo.3
+++ b/lib/libc/net/getaddrinfo.3
@@ -1,4 +1,7 @@
 .\" Copyright (c) 1983, 1987, 1991, 1993
+.\"	$FreeBSD$
+.\"	$KAME: getaddrinfo.3,v 1.16 2000/07/05 08:18:42 itojun Exp $
+.\"
 .\"	The Regents of the University of California.  All rights reserved.
 .\"
 .\" Redistribution and use in source and binary forms, with or without
@@ -30,15 +33,13 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     From: @(#)gethostbyname.3	8.4 (Berkeley) 5/25/95
-.\"     $Id: getaddrinfo.3,v 1.3 1999/10/07 08:22:04 jinmei Exp $
-.\"	$FreeBSD$
 .\"
 .Dd May 25, 1995
 .Dt GETADDRINFO 3
 .Os KAME
 .\"
 .Sh NAME
-.Nm getaddrinfo
+.Nm getaddrinfo ,
 .Nm freeaddrinfo ,
 .Nm gai_strerror
 .Nd nodename-to-address translation in protocol-independent manner
@@ -50,7 +51,8 @@
 .Fd #include <sys/socket.h>
 .Fd #include <netdb.h>
 .Ft int
-.Fn getaddrinfo "const char *nodename" "const char *servname" "const struct addrinfo *hints" "struct addrinfo **res"
+.Fn getaddrinfo "const char *nodename" "const char *servname" \
+"const struct addrinfo *hints" "struct addrinfo **res"
 .Ft void
 .Fn freeaddrinfo "struct addrinfo *ai"
 .Ft "char *"
@@ -60,14 +62,16 @@
 The
 .Fn getaddrinfo
 function is defined for protocol-independent nodename-to-address translation.
-It performs functionality of
+It performs the functionality of
 .Xr gethostbyname 3
 and
 .Xr getservbyname 3 ,
-in more sophisticated manner.
+but in a more sophisticated manner.
 .Pp
-The addrinfo structure is defined as a result of including the
-.Li <netdb.h>
+The
+.Li addrinfo
+structure is defined as a result of including the
+.Aq Pa netdb.h
 header:
 .Bd -literal -offset
 struct addrinfo {                                                  *
@@ -161,7 +165,8 @@ pointer, this is the same as if the caller had filled in an
 .Li addrinfo
 structure initialized to zero with
 .Fa ai_family
-set to PF_UNSPEC.
+set to
+.Dv PF_UNSPEC .
 .Pp
 Upon successful return a pointer to a linked list of one or more
 .Li addrinfo
@@ -224,7 +229,8 @@ call to
 .Pq for a connection-oriented protocol
 or either
 .Fn connect ,
-.Fn sendto , or
+.Fn sendto ,
+or
 .Fn sendmsg
 .Pq for a connectionless protocol .
 In this case, if the
@@ -269,7 +275,7 @@ All of the information returned by
 is dynamically allocated:
 the
 .Li addrinfo
-structures, and the socket address structures and canonical node name
+structures, the socket address structures, and canonical node name
 strings pointed to by the addrinfo structures.
 To return this information to the system the function
 .Fn freeaddrinfo
@@ -316,7 +322,7 @@ such as
 .Li ne0
 .Pc .
 Example would be like
-.Dq Li fe80::1@ne0 ,
+.Dq Li fe80::1%ne0 ,
 which means
 .Do
 .Li fe80::1
@@ -329,6 +335,105 @@ The implementation is still very experimental and non-standard.
 The current implementation assumes one-by-one relationship between
 interface and link, which is not necessarily true from the specification.
 .\"
+.Sh EXAMPLES
+The following code tries to connect to
+.Dq Li www.kame.net
+service
+.Dq Li http .
+via stream socket.
+It loops through all the addresses available, regardless from address family.
+If the destination resolves to IPv4 address, it will use
+.Dv AF_INET
+socket.
+Similarly, if it resolves to IPv6,
+.Dv AF_INET6
+socket is used.
+Observe that there is no hardcoded reference to particular address family.
+The code works even if
+.Nm getaddrinfo
+returns addresses that are not IPv4/v6.
+.Bd -literal -offset indent
+struct addrinfo hints, *res, *res0;
+int error;
+int s;
+const char *cause = NULL;
+
+memset(&hints, 0, sizeof(hints));
+hints.ai_family = PF_UNSPEC;
+hints.ai_socktype = SOCK_STREAM;
+error = getaddrinfo("www.kame.net", "http", &hints, &res0);
+if (error) {
+	err1(1, "%s", gai_strerror(error));
+	/*NOTREACHED*/
+}
+s = -1;
+for (res = res0; res; res = res->ai_next) {
+	s = socket(res->ai_family, res->ai_socktype,
+	    res->ai_protocol);
+	if (s < 0) {
+		cause = "socket";
+		continue;
+	}
+
+	if (connect(s, res->ai_addr, res->ai_addrlen) < 0) {
+		cause = "connect";
+		close(s);
+		s = -1;
+		continue;
+	}
+
+	break;	/* okay we got one */
+}
+if (s < 0) {
+	err(1, cause);
+	/*NOTREACHED*/
+}
+freeaddrinfo(res0);
+.Ed
+.Pp
+The following example tries to open wildcard listening socket onto service
+.Dq Li http ,
+for all the address families available.
+.Bd -literal -offset indent
+struct addrinfo hints, *res, *res0;
+int error;
+int s[MAXSOCK];
+int nsock;
+const char *cause = NULL;
+
+memset(&hints, 0, sizeof(hints));
+hints.ai_family = PF_UNSPEC;
+hints.ai_socktype = SOCK_STREAM;
+hints.ai_flags = AI_PASSIVE;
+error = getaddrinfo(NULL, "http", &hints, &res0);
+if (error) {
+	err1(1, "%s", gai_strerror(error));
+	/*NOTREACHED*/
+}
+nsock = 0;
+for (res = res0; res && nsock < MAXSOCK; res = res->ai_next) {
+	s[nsock] = socket(res->ai_family, res->ai_socktype,
+	    res->ai_protocol);
+	if (s[nsock] < 0) {
+		cause = "socket";
+		continue;
+	}
+
+	if (connect(s[nsock], res->ai_addr, res->ai_addrlen) < 0) {
+		cause = "connect";
+		close(s[nsock]);
+		continue;
+	}
+
+	nsock++;
+}
+if (nsock == 0) {
+	err(1, cause);
+	/*NOTREACHED*/
+}
+freeaddrinfo(res0);
+.Ed
+.\"
 .Sh FILES
 .Bl -tag -width /etc/resolv.conf -compact
 .It Pa /etc/hosts
@@ -341,32 +446,44 @@ Error return status from
 .Fn getaddrinfo
 is zero on success and non-zero on errors.
 Non-zero error codes are defined in
-.Li <netdb.h> ,
+.Aq Pa netdb.h ,
 and as follows:
 .Pp
 .Bl -tag -width EAI_ADDRFAMILY -compact
 .It Dv EAI_ADDRFAMILY
-address family for nodename not supported
+Address family for
+.Fa nodename
+not supported.
 .It Dv EAI_AGAIN
-temporary failure in name resolution
+Temporary failure in name resolution.
 .It Dv EAI_BADFLAGS
-invalid value for ai_flags
+Invalid value for
+.Fa ai_flags .
 .It Dv EAI_FAIL
-non-recoverable failure in name resolution
+Non-recoverable failure in name resolution.
 .It Dv EAI_FAMILY
-ai_family not supported
+.Fa ai_family
+not supported.
 .It Dv EAI_MEMORY
-memory allocation failure
+Memory allocation failure.
 .It Dv EAI_NODATA
-no address associated with nodename
+No address associated with
+.Fa nodename .
 .It Dv EAI_NONAME
-nodename nor servname provided, or not known
+.Fa nodename
+nor
+.Fa servname
+provided, or not known.
 .It Dv EAI_SERVICE
-servname not supported for ai_socktype
+.Fa servname
+not supported for
+.Fa ai_socktype .
 .It Dv EAI_SOCKTYPE
-ai_socktype not supported
+.Fa ai_socktype
+not supported.
 .It Dv EAI_SYSTEM
-system error returned in errno
+System error returned in
+.Va errno .
 .El
 .Pp
 If called with proper argument,
@@ -384,7 +501,7 @@ indicate an unknown error.
 .Xr hosts 5 ,
 .Xr services 5 ,
 .Xr hostname 7 ,
-.Xr named 8 .
+.Xr named 8
 .Pp
 .Rs
 .%A R. Gilligan
@@ -395,6 +512,20 @@ indicate an unknown error.
 .%R RFC2553
 .%D March 1999
 .Re
+.Rs
+.%A Tatsuya Jinmei
+.%A Atsushi Onoe
+.%T "An Extension of Format for IPv6 Scoped Addresses"
+.%R internet draft
+.%N draft-ietf-ipngwg-scopedaddr-format-02.txt
+.%O work in progress material
+.Re
+.Rs
+.%A Craig Metz
+.%T Protocol Independence Using the Sockets API
+.%B "Proceedings of the freenix track: 2000 USENIX annual technical conference"
+.%D June 2000
+.Re
 .\"
 .Sh HISTORY
 The implementation first appeared in WIDE Hydrangea IPv6 protocol stack kit.
@@ -403,8 +534,9 @@ The implementation first appeared in WIDE Hydrangea IPv6 protocol stack kit.
 The
 .Fn getaddrinfo
 function is defined IEEE POSIX 1003.1g draft specification,
-and documented in ``Basic Socket Interface Extensions for IPv6''
-.Pq RFC2533 .
+and documented in
+.Dq Basic Socket Interface Extensions for IPv6
+.Pq RFC2553 .
 .\"
 .Sh BUGS
 The text was shamelessly copied from RFC2553.
diff --git a/lib/libc/net/getaddrinfo.c b/lib/libc/net/getaddrinfo.c
index af7964493bc2..f44a14d79919 100644
--- a/lib/libc/net/getaddrinfo.c
+++ b/lib/libc/net/getaddrinfo.c
@@ -1,3 +1,6 @@
+/*	$FreeBSD$	*/
+/*	$KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $	*/
+
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  * All rights reserved.
@@ -25,8 +28,6 @@
  * 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.
- *
- * $FreeBSD$
  */
 
 /*
@@ -195,7 +196,7 @@ typedef union {
 struct res_target {
 	struct res_target *next;
 	const char *name;	/* domain name */
-	int class, type;	/* class and type of query */
+	int qclass, qtype;	/* class and type of query */
 	u_char *answer;		/* buffer to put answer */
 	int anslen;		/* size of answer buffer */
 	int n;			/* result length */
@@ -256,7 +257,9 @@ static char *ai_errlist[] = {
 	"System error returned in errno", 		/* EAI_SYSTEM     */
 	"Invalid value for hints",			/* EAI_BADHINTS	  */
 	"Resolved protocol is unknown",			/* EAI_PROTOCOL   */
+#ifdef EAI_RESNULL
 	"Argument res is NULL",				/* EAI_RESNULL	  */
+#endif
 	"Unknown error", 				/* EAI_MAX        */
 };
 
@@ -356,13 +359,16 @@ static int
 str_isnumber(p)
 	const char *p;
 {
-	const char *q = (const char *)p;
-	while (*q) {
-		if (!isdigit(*q))
-			return NO;
-		q++;
-	}
-	return YES;
+	char *ep;
+
+	if (*p == '\0')
+		return NO;
+	ep = NULL;
+	(void)strtoul(p, &ep, 10);
+	if (ep && *ep == '\0')
+		return YES;
+	else
+		return NO;
 }
 
 int
@@ -393,8 +399,10 @@ getaddrinfo(hostname, servname, hints, res)
 
 	if (hostname == NULL && servname == NULL)
 		return EAI_NONAME;
+#ifdef EAI_RESNULL
 	if (res == NULL)
 		return EAI_RESNULL; /* xxx */
+#endif
 	if (hints) {
 		/* error check for hints */
 		if (hints->ai_addrlen || hints->ai_canonname ||
@@ -529,9 +537,9 @@ getaddrinfo(hostname, servname, hints, res)
 		goto good;
 
 	if (pai->ai_flags & AI_NUMERICHOST)
-		ERR(EAI_NONAME);
+		ERR(EAI_NODATA);
 	if (hostname == NULL)
-		ERR(EAI_NONAME);
+		ERR(EAI_NODATA);
 
 #if 1
 	/* XXX: temporarily, behave as if AI_ADDRCONFIG is specified */
@@ -812,17 +820,33 @@ explore_numeric(pai, hostname, servname, res)
 	if (afd == NULL)
 		return 0;
 
-	if ((afd->a_af == AF_INET
-	     ? inet_aton(hostname, (struct in_addr *)pton)
-	     : 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 && cur->ai_next)
-				cur = cur->ai_next;
-		} else
-			ERR(EAI_FAMILY);	/*xxx*/
+	switch (afd->a_af) {
+#if 1 /*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 && cur->ai_next)
+					cur = cur->ai_next;
+			} else
+				ERR(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 && cur->ai_next)
+					cur = cur->ai_next;
+			} else
+				ERR(EAI_FAMILY);	/*xxx*/
+		}
+		break;
 	}
 
 	*res = sentinel.ai_next;
@@ -891,7 +915,7 @@ explore_numeric_scope(pai, hostname, servname, res)
 			sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
 			if ((scopeid = ip6_str2scopeid(scope, sin6)) == -1) {
 				free(hostname2);
-				return(EAI_NONAME); /* XXX: is return OK? */
+				return(EAI_NODATA); /* XXX: is return OK? */
 			}
 			sin6->sin6_scope_id = scopeid;
 		}
@@ -1150,6 +1174,10 @@ ip6_str2scopeid(scope, sin6)
 	struct in6_addr *a6 = &sin6->sin6_addr;
 	char *ep;
 
+	/* empty scopeid portion is invalid */
+	if (*scope == '\0')
+		return -1;
+
 	if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
 		/*
 		 * We currently assume a one-to-one mapping between links
@@ -1406,25 +1434,25 @@ _dns_getaddrinfo(pai, hostname, res)
 	switch (pai->ai_family) {
 	case AF_UNSPEC:
 		/* prefer IPv6 */
-		q.class = C_IN;
-		q.type = T_AAAA;
+		q.qclass = C_IN;
+		q.qtype = T_AAAA;
 		q.answer = buf.buf;
 		q.anslen = sizeof(buf);
 		q.next = &q2;
-		q2.class = C_IN;
-		q2.type = T_A;
+		q2.qclass = C_IN;
+		q2.qtype = T_A;
 		q2.answer = buf2.buf;
 		q2.anslen = sizeof(buf2);
 		break;
 	case AF_INET:
-		q.class = C_IN;
-		q.type = T_A;
+		q.qclass = C_IN;
+		q.qtype = T_A;
 		q.answer = buf.buf;
 		q.anslen = sizeof(buf);
 		break;
 	case AF_INET6:
-		q.class = C_IN;
-		q.type = T_AAAA;
+		q.qclass = C_IN;
+		q.qtype = T_AAAA;
 		q.answer = buf.buf;
 		q.anslen = sizeof(buf);
 		break;
@@ -1433,14 +1461,14 @@ _dns_getaddrinfo(pai, hostname, res)
 	}
 	if (res_searchN(hostname, &q) < 0)
 		return EAI_NODATA;
-	ai = getanswer(&buf, q.n, q.name, q.type, pai);
+	ai = getanswer(&buf, q.n, q.name, q.qtype, pai);
 	if (ai) {
 		cur->ai_next = ai;
 		while (cur && cur->ai_next)
 			cur = cur->ai_next;
 	}
 	if (q.next) {
-		ai = getanswer(&buf2, q2.n, q2.name, q2.type, pai);
+		ai = getanswer(&buf2, q2.n, q2.name, q2.qtype, pai);
 		if (ai)
 			cur->ai_next = ai;
 	}
@@ -1672,8 +1700,8 @@ res_queryN(name, target)
 		hp->rcode = NOERROR;	/* default */
 
 		/* make it easier... */
-		class = t->class;
-		type = t->type;
+		class = t->qclass;
+		type = t->qtype;
 		answer = t->answer;
 		anslen = t->anslen;
 #ifdef DEBUG
diff --git a/lib/libc/net/getnameinfo.3 b/lib/libc/net/getnameinfo.3
index 84b98cb025dd..0b4785724eb1 100644
--- a/lib/libc/net/getnameinfo.3
+++ b/lib/libc/net/getnameinfo.3
@@ -1,3 +1,6 @@
+.\"	$FreeBSD$
+.\"	$KAME: getnameinfo.3,v 1.16 2000/07/05 08:22:04 itojun Exp $
+.\"
 .\" Copyright (c) 1983, 1987, 1991, 1993
 .\"	The Regents of the University of California.  All rights reserved.
 .\"
@@ -30,8 +33,6 @@
 .\" SUCH DAMAGE.
 .\"
 .\"     From: @(#)gethostbyname.3	8.4 (Berkeley) 5/25/95
-.\"     $Id: getnameinfo.3,v 1.2 1999/10/07 04:46:27 itojun Exp $
-.\"	$FreeBSD$
 .\"
 .Dd May 25, 1995
 .Dt GETNAMEINFO 3
@@ -48,7 +49,8 @@
 .Fd #include <sys/socket.h>
 .Fd #include <netdb.h>
 .Ft int
-.Fn getnameinfo "const struct sockaddr *sa" "socklen_t salen" "char *host" "size_t hostlen" "char *serv" "size_t servlen" "int flags"
+.Fn getnameinfo "const struct sockaddr *sa" "socklen_t salen" \
+"char *host" "size_t hostlen" "char *serv" "size_t servlen" "int flags"
 .\"
 .Sh DESCRIPTION
 The
@@ -70,16 +72,16 @@ a non-zero return value indicates failure.
 The first argument,
 .Fa sa ,
 points to either a
-.Fa sockaddr_in
+.Li sockaddr_in
 structure (for IPv4) or a
-.Fa sockaddr_in6
+.Li sockaddr_in6
 structure (for IPv6) that holds the IP address and port number.
 The
 .Fa salen
 argument gives the length of the
-.Fa sockaddr_in
+.Li sockaddr_in
 or
-.Fa sockaddr_in6
+.Li sockaddr_in6
 structure.
 .Pp
 The function returns the nodename associated with the IP address in
@@ -102,22 +104,22 @@ or
 .Fa servlen
 arguments.
 Otherwise, the caller must provide buffers large enough to hold the
-nodename and the  service name, including the terminating null characters.
+nodename and the service name, including the terminating null characters.
 .Pp
 Unfortunately most systems do not provide constants that specify the
 maximum size of either a fully-qualified domain name or a service name.
 Therefore to aid the application in allocating buffers for these two
 returned strings the following constants are defined in
-.Li <netdb.h> :
+.Aq Pa netdb.h :
 .Bd -literal -offset
-#define	NI_MAXHOST  1025
-#define	NI_MAXSERV    32
+#define NI_MAXHOST  1025
+#define NI_MAXSERV    32
 .Ed
 .Pp
 The first value is actually defined as the constant
 .Dv MAXDNAME
 in recent versions of BIND's
-.Li <arpa/nameser.h>
+.Aq Pa arpa/nameser.h
 header
 .Po
 older versions of BIND define this constant to be 256
@@ -160,27 +162,30 @@ instead of its name.
 The two
 .Dv NI_NUMERICxxx
 flags are required to support the
-.Li "-n"
+.Fl n
 flag that many commands provide.
 .Pp
 A fifth flag bit,
 .Dv NI_DGRAM ,
 specifies that the service is a datagram service, and causes
 .Fn getservbyport
-to be called with a second argument of "udp" instead of its default of "tcp".
+to be called with a second argument of
+.Dq udp
+instead of its default of
+.Dq tcp .
 This is required for the few ports (512-514)
 that have different services for UDP and TCP.
 .Pp
 These
 .Dv NI_xxx
 flags are defined in
-.Li <netdb.h> .
+.Aq Pa netdb.h .
 .\"
 .Sh EXTENSION
 The implementation allows experimental numeric IPv6 address notation with
 scope identifier.
 IPv6 link-local address will appear as string like
-.Dq Li fe80::1@ne0 ,
+.Dq Li fe80::1%ne0 ,
 if
 .Dv NI_WITHSCOPEID
 bit is enabled in
@@ -190,6 +195,35 @@ Refer to
 .Xr getaddrinfo 3
 for the notation.
 .\"
+.Sh EXAMPLES
+The following code tries to get numeric hostname, and service name,
+for given socket address.
+Observe that there is no hardcoded reference to particular address family.
+.Bd -literal -offset indent
+struct sockaddr *sa;	/* input */
+char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
+
+if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), sbuf,
+    sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV)) {
+	errx(1, "could not get numeric hostname");
+	/*NOTREACHED*/
+}
+printf("host=%s, serv=%s\\n", hbuf, sbuf);
+.Ed
+.Pp
+The following version checks if the socket address has reverse address mapping.
+.Bd -literal -offset indent
+struct sockaddr *sa;	/* input */
+char hbuf[NI_MAXHOST];
+
+if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0,
+    NI_NAMEREQD)) {
+	errx(1, "could not resolve hostname");
+	/*NOTREACHED*/
+}
+printf("host=%s\\n", hbuf);
+.Ed
+.\"
 .Sh FILES
 .Bl -tag -width /etc/resolv.conf -compact
 .It Pa /etc/hosts
@@ -200,6 +234,29 @@ for the notation.
 .Sh DIAGNOSTICS
 The function indicates successful completion by a zero return value;
 a non-zero return value indicates failure.
+Error codes are as below:
+.Bl -tag -width Er
+.It Bq Er EAI_AGAIN
+The name could not be resolved at this time.
+Future attempts may succeed.
+.It Bq Er EAI_BADFLAGS
+The flags had an invalid value.
+.It Bq Er EAI_FAIL
+A non-recoverable error occurred.
+.It Bq Er EAI_FAMILY
+The address family was not recognized or the address length was invalid
+for the specified family.
+.It Bq Er EAI_MEMORY
+There was a memory allocation failure.
+.It Bq Er EAI_NONAME
+The name does not resolve for the supplied parameters.
+.Dv NI_NAMEREQD
+is set and the host's name cannot be located,
+or both nodename and servname were null.
+.It Bq Er EAI_SYSTEM
+A system error occurred.
+The error code can be found in errno.
+.El
 .\"
 .Sh SEE ALSO
 .Xr getaddrinfo 3 ,
@@ -219,6 +276,20 @@ a non-zero return value indicates failure.
 .%R RFC2553
 .%D March 1999
 .Re
+.Rs
+.%A Tatsuya Jinmei
+.%A Atsushi Onoe
+.%T "An Extension of Format for IPv6 Scoped Addresses"
+.%R internet draft
+.%N draft-ietf-ipngwg-scopedaddr-format-02.txt
+.%O work in progress material
+.Re
+.Rs
+.%A Craig Metz
+.%T Protocol Independence Using the Sockets API
+.%B "Proceedings of the freenix track: 2000 USENIX annual technical conference"
+.%D June 2000
+.Re
 .\"
 .Sh HISTORY
 The implementation first appeared in WIDE Hydrangea IPv6 protocol stack kit.
@@ -227,8 +298,14 @@ The implementation first appeared in WIDE Hydrangea IPv6 protocol stack kit.
 The
 .Fn getaddrinfo
 function is defined IEEE POSIX 1003.1g draft specification,
-and documented in ``Basic Socket Interface Extensions for IPv6''
-.Pq RFC2533 .
+and documented in
+.Dq Basic Socket Interface Extensions for IPv6
+.Pq RFC2553 .
 .\"
 .Sh BUGS
 The text was shamelessly copied from RFC2553.
+.Pp
+The type of the 2nd argument should be
+.Li socklen_t
+for RFC2553 conformance.
+The current code is based on pre-RFC2553 specification.
diff --git a/lib/libc/net/getnameinfo.c b/lib/libc/net/getnameinfo.c
index 5edcffb9498c..2dbd81fe2d52 100644
--- a/lib/libc/net/getnameinfo.c
+++ b/lib/libc/net/getnameinfo.c
@@ -1,3 +1,6 @@
+/*	$FreeBSD$	*/
+/*	$KAME: getnameinfo.c,v 1.43 2000/06/12 04:27:03 itojun Exp $	*/
+
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
  * All rights reserved.
@@ -25,8 +28,6 @@
  * 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.
- *
- * $FreeBSD$
  */
 
 /*
@@ -34,6 +35,13 @@
  * - Thread safe-ness must be checked
  * - Return values.  There seems to be no standard for return value (RFC2553)
  *   but INRIA implementation returns EAI_xxx defined for getaddrinfo().
+ * - RFC2553 says that we should raise error on short buffer.  X/Open says
+ *   we need to truncate the result.  We obey RFC2553 (and X/Open should be
+ *   modified).
+ * - What is "local" in NI_FQDN?
+ * - NI_NAMEREQD and NI_NUMERICHOST conflict with each other.
+ * - (KAME extension) NI_WITHSCOPEID when called with global address,
+ *   and sin6_scope_id filled
  */
 
 #include <sys/types.h>
@@ -46,11 +54,12 @@
 #include <resolv.h>
 #include <string.h>
 #include <stddef.h>
+#include <errno.h>
 
-#define	SUCCESS 0
-#define	ANY 0
-#define	YES 1
-#define	NO  0
+#define SUCCESS 0
+#define ANY 0
+#define YES 1
+#define NO  0
 
 static struct afd {
 	int a_af;
@@ -73,13 +82,19 @@ struct sockinet {
 	u_short	si_port;
 };
 
-#define	ENI_NOSOCKET 	0
-#define	ENI_NOSERVHOST	1
-#define	ENI_NOHOSTNAME	2
-#define	ENI_MEMORY	3
-#define	ENI_SYSTEM	4
-#define	ENI_FAMILY	5
-#define	ENI_SALEN	6
+#ifdef INET6
+static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *,
+				 size_t, int));
+static int ip6_sa2str __P((const struct sockaddr_in6 *, char *, size_t, int));
+#endif
+
+#define ENI_NOSOCKET 	EAI_FAIL		/*XXX*/
+#define ENI_NOSERVNAME	EAI_NONAME
+#define ENI_NOHOSTNAME	EAI_NONAME
+#define ENI_MEMORY	EAI_MEMORY
+#define ENI_SYSTEM	EAI_SYSTEM
+#define ENI_FAMILY	EAI_FAMILY
+#define ENI_SALEN	EAI_FAMILY
 
 int
 getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
@@ -96,19 +111,18 @@ getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 	struct hostent *hp;
 	u_short port;
 	int family, i;
-	char *addr, *p;
-	u_long v4a;
+	const char *addr;
+	u_int32_t v4a;
 	int h_error;
 	char numserv[512];
 	char numaddr[512];
-	int noserv = 0;
 
 	if (sa == NULL)
 		return ENI_NOSOCKET;
 
 	if (sa->sa_len != salen)
 		return ENI_SALEN;
-
+	
 	family = sa->sa_family;
 	for (i = 0; afdl[i].a_af; i++)
 		if (afdl[i].a_af == family) {
@@ -116,16 +130,22 @@ getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 			goto found;
 		}
 	return ENI_FAMILY;
-
+	
  found:
 	if (salen != afd->a_socklen)
 		return ENI_SALEN;
-
-	port = ((struct sockinet *)sa)->si_port; /* network byte order */
-	addr = (char *)sa + afd->a_off;
+	
+	/* network byte order */
+	port = ((const struct sockinet *)sa)->si_port;
+	addr = (const char *)sa + afd->a_off;
 
 	if (serv == NULL || servlen == 0) {
-		noserv = 1;
+		/*
+		 * do nothing in this case.
+		 * in case you are wondering if "&&" is more correct than
+		 * "||" here: RFC2553 says that serv == NULL OR servlen == 0
+		 * means that the caller does not want the result.
+		 */
 	} else {
 		if (flags & NI_NUMERICSERV)
 			sp = NULL;
@@ -147,73 +167,92 @@ getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 
 	switch (sa->sa_family) {
 	case AF_INET:
-		v4a = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
+		v4a = (u_int32_t)
+		    ntohl(((const struct sockaddr_in *)sa)->sin_addr.s_addr);
 		if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
 			flags |= NI_NUMERICHOST;
 		v4a >>= IN_CLASSA_NSHIFT;
 		if (v4a == 0)
-			flags |= NI_NUMERICHOST;
+			flags |= NI_NUMERICHOST;			
 		break;
 #ifdef INET6
 	case AF_INET6:
 	    {
-		struct sockaddr_in6 *sin6;
-		sin6 = (struct sockaddr_in6 *)sa;
-		if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) ||
-		    IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
-			flags |= NI_NUMERICHOST;
+		const struct sockaddr_in6 *sin6;
+		sin6 = (const struct sockaddr_in6 *)sa;
+		switch (sin6->sin6_addr.s6_addr[0]) {
+		case 0x00:
+			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
+				;
+			else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr))
+				;
+			else
+				flags |= NI_NUMERICHOST;
+			break;
+		default:
+			if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
+				flags |= NI_NUMERICHOST;
+			}
+			else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
+				flags |= NI_NUMERICHOST;
+			break;
+		}
 	    }
 		break;
 #endif
 	}
 	if (host == NULL || hostlen == 0) {
-		if (noserv == 1)
-			return ENI_NOSERVHOST;
+		/*
+		 * do nothing in this case.
+		 * in case you are wondering if "&&" is more correct than
+		 * "||" here: RFC2553 says that host == NULL OR hostlen == 0
+		 * means that the caller does not want the result.
+		 */
 	} else if (flags & NI_NUMERICHOST) {
+		int numaddrlen;
+
 		/* NUMERICHOST and NAMEREQD conflicts with each other */
 		if (flags & NI_NAMEREQD)
 			return ENI_NOHOSTNAME;
-		if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
-		    == NULL)
-			return ENI_SYSTEM;
-		if (strlen(numaddr) > hostlen)
-			return ENI_MEMORY;
-		strcpy(host, numaddr);
+
+		switch(afd->a_af) {
 #ifdef INET6
-		if (afd->a_af == AF_INET6 &&
-		    (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)addr) ||
-		     IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) &&
-		    ((struct sockaddr_in6 *)sa)->sin6_scope_id) {
-			if (flags & NI_WITHSCOPEID) {
-				char *ep = strchr(host, '\0');
-				unsigned int ifindex =
-					((struct sockaddr_in6 *)sa)->sin6_scope_id;
-				char ifname[IF_NAMESIZE * 2 /* for safety */];
-				int scopelen, numaddrlen;
-
-				if ((if_indextoname(ifindex, ifname)) == NULL)
-					return ENI_SYSTEM;
-				scopelen = strlen(ifname);
-				numaddrlen = strlen(host);
-				if (numaddrlen + 1 /* SCOPE_DELIMITER */
-				    + scopelen > hostlen)
-					return ENI_MEMORY;
-				/*
-				 * Construct <numeric-addr><delim><scopeid>
-				 */
-				memcpy(host + numaddrlen + 1, ifname, scopelen);
-				host[numaddrlen] = SCOPE_DELIMITER;
-				host[numaddrlen + 1 + scopelen] = '\0';
-			}
+		case AF_INET6:
+		{
+			int error;
+
+			if ((error = ip6_parsenumeric(sa, addr, host,
+						      hostlen, flags)) != 0)
+				return(error);
+			break;
+		}
+#endif
+		default:
+			if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
+			    == NULL)
+				return ENI_SYSTEM;
+			numaddrlen = strlen(numaddr);
+			if (numaddrlen + 1 > hostlen) /* don't forget terminator */
+				return ENI_MEMORY;
+			strcpy(host, numaddr);
+			break;
 		}
-#endif /* INET6 */
 	} else {
 		hp = getipnodebyaddr(addr, afd->a_addrlen, afd->a_af, &h_error);
+
 		if (hp) {
+#if 0
+			/*
+			 * commented out, since "for local host" is not
+			 * implemented here - see RFC2553 p30
+			 */
 			if (flags & NI_NOFQDN) {
+				char *p;
 				p = strchr(hp->h_name, '.');
-				if (p) *p = '\0';
+				if (p)
+					*p = '\0';
 			}
+#endif
 			if (strlen(hp->h_name) > hostlen) {
 				freehostent(hp);
 				return ENI_MEMORY;
@@ -223,13 +262,112 @@ getnameinfo(sa, salen, host, hostlen, serv, servlen, flags)
 		} else {
 			if (flags & NI_NAMEREQD)
 				return ENI_NOHOSTNAME;
-			if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
-			    == NULL)
-				return ENI_NOHOSTNAME;
-			if (strlen(numaddr) > hostlen)
-				return ENI_MEMORY;
-			strcpy(host, numaddr);
+			switch(afd->a_af) {
+#ifdef INET6
+			case AF_INET6:
+			{
+				int error;
+
+				if ((error = ip6_parsenumeric(sa, addr, host,
+							      hostlen,
+							      flags)) != 0)
+					return(error);
+				break;
+			}
+#endif
+			default:
+				if (inet_ntop(afd->a_af, addr, host,
+				    hostlen) == NULL)
+					return ENI_SYSTEM;
+				break;
+			}
 		}
 	}
 	return SUCCESS;
 }
+
+#ifdef INET6
+static int
+ip6_parsenumeric(sa, addr, host, hostlen, flags)
+	const struct sockaddr *sa;
+	const char *addr;
+	char *host;
+	size_t hostlen;
+	int flags;
+{
+	int numaddrlen;
+	char numaddr[512];
+
+	if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr))
+	    == NULL)
+		return ENI_SYSTEM;
+
+	numaddrlen = strlen(numaddr);
+	if (numaddrlen + 1 > hostlen) /* don't forget terminator */
+		return ENI_MEMORY;
+	strcpy(host, numaddr);
+
+#ifdef NI_WITHSCOPEID
+	if (
+#ifdef DONT_OPAQUE_SCOPEID
+	    (IN6_IS_ADDR_LINKLOCAL((struct in6_addr *)addr) ||
+	     IN6_IS_ADDR_MULTICAST((struct in6_addr *)addr)) &&
+#endif
+	    ((const struct sockaddr_in6 *)sa)->sin6_scope_id) {
+#ifndef ALWAYS_WITHSCOPE
+		if (flags & NI_WITHSCOPEID)
+#endif /* !ALWAYS_WITHSCOPE */
+		{
+			char scopebuf[MAXHOSTNAMELEN];
+			int scopelen;
+
+			/* ip6_sa2str never fails */
+			scopelen = ip6_sa2str((const struct sockaddr_in6 *)sa,
+					      scopebuf, sizeof(scopebuf),
+					      flags);
+			if (scopelen + 1 + numaddrlen + 1 > hostlen)
+				return ENI_MEMORY;
+			/*
+			 * construct <numeric-addr><delim><scopeid>
+			 */
+			memcpy(host + numaddrlen + 1, scopebuf,
+			       scopelen);
+			host[numaddrlen] = SCOPE_DELIMITER;
+			host[numaddrlen + 1 + scopelen] = '\0';
+		}
+	}
+#endif /* NI_WITHSCOPEID */
+
+	return 0;
+}
+
+/* ARGSUSED */
+static int
+ip6_sa2str(sa6, buf, bufsiz, flags)
+	const struct sockaddr_in6 *sa6;
+	char *buf;
+	size_t bufsiz;
+	int flags;
+{
+	unsigned int ifindex = (unsigned int)sa6->sin6_scope_id;
+	const struct in6_addr *a6 = &sa6->sin6_addr;
+
+#ifdef NI_NUMERICSCOPE
+	if (flags & NI_NUMERICSCOPE) {
+		return(snprintf(buf, bufsiz, "%d", sa6->sin6_scope_id));
+	}
+#endif
+
+	/* if_indextoname() does not take buffer size.  not a good api... */
+	if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) &&
+	    bufsiz >= IF_NAMESIZE) {
+		char *p = if_indextoname(ifindex, buf);
+		if (p) {
+			return(strlen(p));
+		}
+	}
+
+	/* last resort */
+	return(snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id));
+}
+#endif /* INET6 */
diff --git a/lib/libc/net/rcmd.c b/lib/libc/net/rcmd.c
index 5bbef4bb4a85..70a18d449f3f 100644
--- a/lib/libc/net/rcmd.c
+++ b/lib/libc/net/rcmd.c
@@ -182,8 +182,8 @@ rcmd_af(ahost, rport, locuser, remuser, cmd, fd2p, af)
 			refused = 0;
 			continue;
 		}
-		freeaddrinfo(res);
 		(void)fprintf(stderr, "%s: %s\n", *ahost, strerror(errno));
+		freeaddrinfo(res);
 		sigsetmask(oldmask);
 		return (-1);
 	}