Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/snmpd/util.c	Lines:	0	144	0.0 %
Date:	2017-11-13	Branches:	0	78	0.0 %


/*	$OpenBSD: util.c,v 1.7 2017/01/09 14:49:22 reyk Exp $	*/
/*
 * Copyright (c) 2014 Bret Stephen Lambert <blambert@openbsd.org>
 *
 * 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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
 */

#include <sys/types.h>
#include <sys/queue.h>
#include <sys/socket.h>

#include <net/if.h>

#include <stdio.h>
#include <string.h>
#include <netdb.h>
#include <event.h>

#include "ber.h"
#include "snmp.h"
#include "snmpd.h"

/*
 * Convert variable bindings from AgentX to SNMP dialect.
 */
int
varbind_convert(struct agentx_pdu *pdu, struct agentx_varbind_hdr *vbhdr,
    struct ber_element **varbind, struct ber_element **iter)
{
	struct ber_oid			 oid;
	u_int32_t			 d;
	u_int64_t			 l;
	int				 slen;
	char				*str;
	struct ber_element		*a;
	int				 ret = AGENTX_ERR_NONE;

	if (snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) {
		ret = AGENTX_ERR_PARSE_ERROR;
		goto done;
	}

	*iter = ber_add_sequence(*iter);
	if (*varbind == NULL)
		*varbind = *iter;

	a = ber_add_oid(*iter, &oid);

	switch (vbhdr->type) {
	case AGENTX_NO_SUCH_OBJECT:
	case AGENTX_NO_SUCH_INSTANCE:
	case AGENTX_END_OF_MIB_VIEW:
	case AGENTX_NULL:
		a = ber_add_null(a);
		break;

	case AGENTX_IP_ADDRESS:
	case AGENTX_OPAQUE:
	case AGENTX_OCTET_STRING:
		str = snmp_agentx_read_octetstr(pdu, &slen);
		if (str == NULL) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_nstring(a, str, slen);
		break;

	case AGENTX_OBJECT_IDENTIFIER:
		if (snmp_agentx_read_oid(pdu,
		    (struct snmp_oid *)&oid) == -1) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_oid(a, &oid);
		break;

	case AGENTX_INTEGER:
	case AGENTX_COUNTER32:
	case AGENTX_GAUGE32:
	case AGENTX_TIME_TICKS:
		if (snmp_agentx_read_int(pdu, &d) == -1) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_integer(a, d);
		break;

	case AGENTX_COUNTER64:
		if (snmp_agentx_read_int64(pdu, &l) == -1) {
			ret = AGENTX_ERR_PARSE_ERROR;
			goto done;
		}
		a = ber_add_integer(a, l);
		break;

	default:
		log_debug("unknown data type '%i'", vbhdr->type);
		ret = AGENTX_ERR_PARSE_ERROR;
		goto done;
	}

	/* AgentX types correspond to BER types */
	switch (vbhdr->type) {
	case BER_TYPE_INTEGER:
	case BER_TYPE_BITSTRING:
	case BER_TYPE_OCTETSTRING:
	case BER_TYPE_NULL:
	case BER_TYPE_OBJECT:
		/* universal types */
		break;

	/* Convert AgentX error types to SNMP error types */
	case AGENTX_NO_SUCH_OBJECT:
		ber_set_header(a, BER_CLASS_CONTEXT, 0);
		break;
	case AGENTX_NO_SUCH_INSTANCE:
		ber_set_header(a, BER_CLASS_CONTEXT, 1);
		break;

	case AGENTX_COUNTER32:
		ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER32);
		break;

	case AGENTX_GAUGE32:
		ber_set_header(a, BER_CLASS_APPLICATION, SNMP_GAUGE32);
		break;

	case AGENTX_COUNTER64:
		ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER64);
		break;

	case AGENTX_IP_ADDRESS:
		/* application 0 implicit 4-byte octet string per SNMPv2-SMI */
		break;

	default:
		/* application-specific types */
		ber_set_header(a, BER_CLASS_APPLICATION, vbhdr->type);
		break;
	}
 done:
	return (ret);
}

ssize_t
sendtofrom(int s, void *buf, size_t len, int flags, struct sockaddr *to,
    socklen_t tolen, struct sockaddr *from, socklen_t fromlen)
{
	struct iovec		 iov;
	struct msghdr		 msg;
	struct cmsghdr		*cmsg;
	struct in6_pktinfo	*pkt6;
	struct sockaddr_in	*in;
	struct sockaddr_in6	*in6;
	union {
		struct cmsghdr	hdr;
		char		inbuf[CMSG_SPACE(sizeof(struct in_addr))];
		char		in6buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
	} cmsgbuf;

	bzero(&msg, sizeof(msg));
	bzero(&cmsgbuf, sizeof(cmsgbuf));

	iov.iov_base = buf;
	iov.iov_len = len;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_name = to;
	msg.msg_namelen = tolen;
	msg.msg_control = &cmsgbuf;
	msg.msg_controllen = sizeof(cmsgbuf);

	cmsg = CMSG_FIRSTHDR(&msg);
	switch (to->sa_family) {
	case AF_INET:
		msg.msg_controllen = sizeof(cmsgbuf.inbuf);
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
		cmsg->cmsg_level = IPPROTO_IP;
		cmsg->cmsg_type = IP_SENDSRCADDR;
		in = (struct sockaddr_in *)from;
		memcpy(CMSG_DATA(cmsg), &in->sin_addr, sizeof(struct in_addr));
		break;
	case AF_INET6:
		msg.msg_controllen = sizeof(cmsgbuf.in6buf);
		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
		cmsg->cmsg_level = IPPROTO_IPV6;
		cmsg->cmsg_type = IPV6_PKTINFO;
		in6 = (struct sockaddr_in6 *)from;
		pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
		pkt6->ipi6_addr = in6->sin6_addr;
		break;
	}

	return sendmsg(s, &msg, flags);
}

ssize_t
recvfromto(int s, void *buf, size_t len, int flags, struct sockaddr *from,
    socklen_t *fromlen, struct sockaddr *to, socklen_t *tolen)
{
	struct iovec		 iov;
	struct msghdr		 msg;
	struct cmsghdr		*cmsg;
	struct in6_pktinfo	*pkt6;
	struct sockaddr_in	*in;
	struct sockaddr_in6	*in6;
	ssize_t			 ret;
	union {
		struct cmsghdr hdr;
		char	buf[CMSG_SPACE(sizeof(struct sockaddr_storage))];
	} cmsgbuf;

	bzero(&msg, sizeof(msg));
	bzero(&cmsgbuf.buf, sizeof(cmsgbuf.buf));

	iov.iov_base = buf;
	iov.iov_len = len;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_name = from;
	msg.msg_namelen = *fromlen;
	msg.msg_control = &cmsgbuf.buf;
	msg.msg_controllen = sizeof(cmsgbuf.buf);

	if ((ret = recvmsg(s, &msg, flags)) == -1)
		return (-1);

	*fromlen = from->sa_len;
	*tolen = 0;

	if (getsockname(s, to, tolen) != 0)
		*tolen = 0;

	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
	    cmsg = CMSG_NXTHDR(&msg, cmsg)) {
		switch (from->sa_family) {
		case AF_INET:
			if (cmsg->cmsg_level == IPPROTO_IP &&
			    cmsg->cmsg_type == IP_RECVDSTADDR) {
				in = (struct sockaddr_in *)to;
				in->sin_family = AF_INET;
				in->sin_len = *tolen = sizeof(*in);
				memcpy(&in->sin_addr, CMSG_DATA(cmsg),
				    sizeof(struct in_addr));
			}
			break;
		case AF_INET6:
			if (cmsg->cmsg_level == IPPROTO_IPV6 &&
			    cmsg->cmsg_type == IPV6_PKTINFO) {
				in6 = (struct sockaddr_in6 *)to;
				in6->sin6_family = AF_INET6;
				in6->sin6_len = *tolen = sizeof(*in6);
				pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
				memcpy(&in6->sin6_addr, &pkt6->ipi6_addr,
				    sizeof(struct in6_addr));
				if (IN6_IS_ADDR_LINKLOCAL(&in6->sin6_addr))
					in6->sin6_scope_id =
					    pkt6->ipi6_ifindex;
			}
			break;
		}
	}

	return (ret);
}

void
print_debug(const char *emsg, ...)
{
	va_list	 ap;

	if (log_getverbose() > 2) {
		va_start(ap, emsg);
		vfprintf(stderr, emsg, ap);
		va_end(ap);
	}
}

void
print_verbose(const char *emsg, ...)
{
	va_list	 ap;

	if (log_getverbose()) {
		va_start(ap, emsg);
		vfprintf(stderr, emsg, ap);
		va_end(ap);
	}
}

const char *
log_in6addr(const struct in6_addr *addr)
{
	static char		buf[NI_MAXHOST];
	struct sockaddr_in6	sa_in6;
	u_int16_t		tmp16;

	bzero(&sa_in6, sizeof(sa_in6));
	sa_in6.sin6_len = sizeof(sa_in6);
	sa_in6.sin6_family = AF_INET6;
	memcpy(&sa_in6.sin6_addr, addr, sizeof(sa_in6.sin6_addr));

	/* XXX thanks, KAME, for this ugliness... adopted from route/show.c */
	if (IN6_IS_ADDR_LINKLOCAL(&sa_in6.sin6_addr) ||
	    IN6_IS_ADDR_MC_LINKLOCAL(&sa_in6.sin6_addr)) {
		memcpy(&tmp16, &sa_in6.sin6_addr.s6_addr[2], sizeof(tmp16));
		sa_in6.sin6_scope_id = ntohs(tmp16);
		sa_in6.sin6_addr.s6_addr[2] = 0;
		sa_in6.sin6_addr.s6_addr[3] = 0;
	}

	return (print_host((struct sockaddr_storage *)&sa_in6, buf,
	    NI_MAXHOST));
}

const char *
print_host(struct sockaddr_storage *ss, char *buf, size_t len)
{
	if (getnameinfo((struct sockaddr *)ss, ss->ss_len,
	    buf, len, NULL, 0, NI_NUMERICHOST) != 0) {
		buf[0] = '\0';
		return (NULL);
	}
	return (buf);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: util.c,v 1.7 2017/01/09 14:49:22 reyk Exp $ */
2			/*
3			* Copyright (c) 2014 Bret Stephen Lambert <blambert@openbsd.org>
4			*
5			* Permission to use, copy, modify, and distribute this software for any
6			* purpose with or without fee is hereby granted, provided that the above
7			* copyright notice and this permission notice appear in all copies.
8			*
9			* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10			* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11			* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12			* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13			* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14			* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15			* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16			*/
17
18			#include <sys/types.h>
19			#include <sys/queue.h>
20			#include <sys/socket.h>
21
22			#include <net/if.h>
23
24			#include <stdio.h>
25			#include <string.h>
26			#include <netdb.h>
27			#include <event.h>
28
29			#include "ber.h"
30			#include "snmp.h"
31			#include "snmpd.h"
32
33			/*
34			* Convert variable bindings from AgentX to SNMP dialect.
35			*/
36			int
37			varbind_convert(struct agentx_pdu pdu, struct agentx_varbind_hdr vbhdr,
38			struct ber_element varbind, struct ber_element iter)
39			{
40			struct ber_oid oid;
41			u_int32_t d;
42			u_int64_t l;
43			int slen;
44			char *str;
45			struct ber_element *a;
46			int ret = AGENTX_ERR_NONE;
47
48			if (snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) {
49			ret = AGENTX_ERR_PARSE_ERROR;
50			goto done;
51			}
52
53			iter = ber_add_sequence(iter);
54			if (*varbind == NULL)
55			varbind = iter;
56
57			a = ber_add_oid(*iter, &oid);
58
59			switch (vbhdr->type) {
60			case AGENTX_NO_SUCH_OBJECT:
61			case AGENTX_NO_SUCH_INSTANCE:
62			case AGENTX_END_OF_MIB_VIEW:
63			case AGENTX_NULL:
64			a = ber_add_null(a);
65			break;
66
67			case AGENTX_IP_ADDRESS:
68			case AGENTX_OPAQUE:
69			case AGENTX_OCTET_STRING:
70			str = snmp_agentx_read_octetstr(pdu, &slen);
71			if (str == NULL) {
72			ret = AGENTX_ERR_PARSE_ERROR;
73			goto done;
74			}
75			a = ber_add_nstring(a, str, slen);
76			break;
77
78			case AGENTX_OBJECT_IDENTIFIER:
79			if (snmp_agentx_read_oid(pdu,
80			(struct snmp_oid *)&oid) == -1) {
81			ret = AGENTX_ERR_PARSE_ERROR;
82			goto done;
83			}
84			a = ber_add_oid(a, &oid);
85			break;
86
87			case AGENTX_INTEGER:
88			case AGENTX_COUNTER32:
89			case AGENTX_GAUGE32:
90			case AGENTX_TIME_TICKS:
91			if (snmp_agentx_read_int(pdu, &d) == -1) {
92			ret = AGENTX_ERR_PARSE_ERROR;
93			goto done;
94			}
95			a = ber_add_integer(a, d);
96			break;
97
98			case AGENTX_COUNTER64:
99			if (snmp_agentx_read_int64(pdu, &l) == -1) {
100			ret = AGENTX_ERR_PARSE_ERROR;
101			goto done;
102			}
103			a = ber_add_integer(a, l);
104			break;
105
106			default:
107			log_debug("unknown data type '%i'", vbhdr->type);
108			ret = AGENTX_ERR_PARSE_ERROR;
109			goto done;
110			}
111
112			/* AgentX types correspond to BER types */
113			switch (vbhdr->type) {
114			case BER_TYPE_INTEGER:
115			case BER_TYPE_BITSTRING:
116			case BER_TYPE_OCTETSTRING:
117			case BER_TYPE_NULL:
118			case BER_TYPE_OBJECT:
119			/* universal types */
120			break;
121
122			/* Convert AgentX error types to SNMP error types */
123			case AGENTX_NO_SUCH_OBJECT:
124			ber_set_header(a, BER_CLASS_CONTEXT, 0);
125			break;
126			case AGENTX_NO_SUCH_INSTANCE:
127			ber_set_header(a, BER_CLASS_CONTEXT, 1);
128			break;
129
130			case AGENTX_COUNTER32:
131			ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER32);
132			break;
133
134			case AGENTX_GAUGE32:
135			ber_set_header(a, BER_CLASS_APPLICATION, SNMP_GAUGE32);
136			break;
137
138			case AGENTX_COUNTER64:
139			ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER64);
140			break;
141
142			case AGENTX_IP_ADDRESS:
143			/* application 0 implicit 4-byte octet string per SNMPv2-SMI */
144			break;
145
146			default:
147			/* application-specific types */
148			ber_set_header(a, BER_CLASS_APPLICATION, vbhdr->type);
149			break;
150			}
151			done:
152			return (ret);
153			}
154
155			ssize_t
156			sendtofrom(int s, void buf, size_t len, int flags, struct sockaddr to,
157			socklen_t tolen, struct sockaddr *from, socklen_t fromlen)
158			{
159			struct iovec iov;
160			struct msghdr msg;
161			struct cmsghdr *cmsg;
162			struct in6_pktinfo *pkt6;
163			struct sockaddr_in *in;
164			struct sockaddr_in6 *in6;
165			union {
166			struct cmsghdr hdr;
167			char inbuf[CMSG_SPACE(sizeof(struct in_addr))];
168			char in6buf[CMSG_SPACE(sizeof(struct in6_pktinfo))];
169			} cmsgbuf;
170
171			bzero(&msg, sizeof(msg));
172			bzero(&cmsgbuf, sizeof(cmsgbuf));
173
174			iov.iov_base = buf;
175			iov.iov_len = len;
176			msg.msg_iov = &iov;
177			msg.msg_iovlen = 1;
178			msg.msg_name = to;
179			msg.msg_namelen = tolen;
180			msg.msg_control = &cmsgbuf;
181			msg.msg_controllen = sizeof(cmsgbuf);
182
183			cmsg = CMSG_FIRSTHDR(&msg);
184			switch (to->sa_family) {
185			case AF_INET:
186			msg.msg_controllen = sizeof(cmsgbuf.inbuf);
187			cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
188			cmsg->cmsg_level = IPPROTO_IP;
189			cmsg->cmsg_type = IP_SENDSRCADDR;
190			in = (struct sockaddr_in *)from;
191			memcpy(CMSG_DATA(cmsg), &in->sin_addr, sizeof(struct in_addr));
192			break;
193			case AF_INET6:
194			msg.msg_controllen = sizeof(cmsgbuf.in6buf);
195			cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
196			cmsg->cmsg_level = IPPROTO_IPV6;
197			cmsg->cmsg_type = IPV6_PKTINFO;
198			in6 = (struct sockaddr_in6 *)from;
199			pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
200			pkt6->ipi6_addr = in6->sin6_addr;
201			break;
202			}
203
204			return sendmsg(s, &msg, flags);
205			}
206
207			ssize_t
208			recvfromto(int s, void buf, size_t len, int flags, struct sockaddr from,
209			socklen_t fromlen, struct sockaddr to, socklen_t *tolen)
210			{
211			struct iovec iov;
212			struct msghdr msg;
213			struct cmsghdr *cmsg;
214			struct in6_pktinfo *pkt6;
215			struct sockaddr_in *in;
216			struct sockaddr_in6 *in6;
217			ssize_t ret;
218			union {
219			struct cmsghdr hdr;
220			char buf[CMSG_SPACE(sizeof(struct sockaddr_storage))];
221			} cmsgbuf;
222
223			bzero(&msg, sizeof(msg));
224			bzero(&cmsgbuf.buf, sizeof(cmsgbuf.buf));
225
226			iov.iov_base = buf;
227			iov.iov_len = len;
228			msg.msg_iov = &iov;
229			msg.msg_iovlen = 1;
230			msg.msg_name = from;
231			msg.msg_namelen = *fromlen;
232			msg.msg_control = &cmsgbuf.buf;
233			msg.msg_controllen = sizeof(cmsgbuf.buf);
234
235			if ((ret = recvmsg(s, &msg, flags)) == -1)
236			return (-1);
237
238			*fromlen = from->sa_len;
239			*tolen = 0;
240
241			if (getsockname(s, to, tolen) != 0)
242			*tolen = 0;
243
244			for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
245			cmsg = CMSG_NXTHDR(&msg, cmsg)) {
246			switch (from->sa_family) {
247			case AF_INET:
248			if (cmsg->cmsg_level == IPPROTO_IP &&
249			cmsg->cmsg_type == IP_RECVDSTADDR) {
250			in = (struct sockaddr_in *)to;
251			in->sin_family = AF_INET;
252			in->sin_len = tolen = sizeof(in);
253			memcpy(&in->sin_addr, CMSG_DATA(cmsg),
254			sizeof(struct in_addr));
255			}
256			break;
257			case AF_INET6:
258			if (cmsg->cmsg_level == IPPROTO_IPV6 &&
259			cmsg->cmsg_type == IPV6_PKTINFO) {
260			in6 = (struct sockaddr_in6 *)to;
261			in6->sin6_family = AF_INET6;
262			in6->sin6_len = tolen = sizeof(in6);
263			pkt6 = (struct in6_pktinfo *)CMSG_DATA(cmsg);
264			memcpy(&in6->sin6_addr, &pkt6->ipi6_addr,
265			sizeof(struct in6_addr));
266			if (IN6_IS_ADDR_LINKLOCAL(&in6->sin6_addr))
267			in6->sin6_scope_id =
268			pkt6->ipi6_ifindex;
269			}
270			break;
271			}
272			}
273
274			return (ret);
275			}
276
277			void
278			print_debug(const char *emsg, ...)
279			{
280			va_list ap;
281
282			if (log_getverbose() > 2) {
283			va_start(ap, emsg);
284			vfprintf(stderr, emsg, ap);
285			va_end(ap);
286			}
287			}
288
289			void
290			print_verbose(const char *emsg, ...)
291			{
292			va_list ap;
293
294			if (log_getverbose()) {
295			va_start(ap, emsg);
296			vfprintf(stderr, emsg, ap);
297			va_end(ap);
298			}
299			}
300
301			const char *
302			log_in6addr(const struct in6_addr *addr)
303			{
304			static char buf[NI_MAXHOST];
305			struct sockaddr_in6 sa_in6;
306			u_int16_t tmp16;
307
308			bzero(&sa_in6, sizeof(sa_in6));
309			sa_in6.sin6_len = sizeof(sa_in6);
310			sa_in6.sin6_family = AF_INET6;
311			memcpy(&sa_in6.sin6_addr, addr, sizeof(sa_in6.sin6_addr));
312
313			/* XXX thanks, KAME, for this ugliness... adopted from route/show.c */
314			if (IN6_IS_ADDR_LINKLOCAL(&sa_in6.sin6_addr) \|\|
315			IN6_IS_ADDR_MC_LINKLOCAL(&sa_in6.sin6_addr)) {
316			memcpy(&tmp16, &sa_in6.sin6_addr.s6_addr[2], sizeof(tmp16));
317			sa_in6.sin6_scope_id = ntohs(tmp16);
318			sa_in6.sin6_addr.s6_addr[2] = 0;
319			sa_in6.sin6_addr.s6_addr[3] = 0;
320			}
321
322			return (print_host((struct sockaddr_storage *)&sa_in6, buf,
323			NI_MAXHOST));
324			}
325
326			const char *
327			print_host(struct sockaddr_storage ss, char buf, size_t len)
328			{
329			if (getnameinfo((struct sockaddr *)ss, ss->ss_len,
330			buf, len, NULL, 0, NI_NUMERICHOST) != 0) {
331			buf[0] = '\0';
332			return (NULL);
333			}
334			return (buf);
335			}