1/*	$OpenBSD: server.c,v 1.44 2016/09/03 11:52:06 reyk Exp $ */
2
3/*
4 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
5 * Copyright (c) 2004 Alexander Guy <alexander@openbsd.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20#include <sys/types.h>
21#include <sys/ioctl.h>
22#include <sys/socket.h>
23#include <net/if.h>
24#include <errno.h>
25#include <ifaddrs.h>
26#include <stdlib.h>
27#include <string.h>
28#include <unistd.h>
29
30#include "ntpd.h"
31
32int
33setup_listeners(struct servent *se, struct ntpd_conf *lconf, u_int *cnt)
34{
35	struct listen_addr	*la, *nla, *lap;
36	struct ifaddrs		*ifa, *ifap;
37	struct sockaddr		*sa;
38	struct if_data		*ifd;
39	u_int8_t		*a6;
40	size_t			 sa6len = sizeof(struct in6_addr);
41	u_int			 new_cnt = 0;
42	int			 tos = IPTOS_LOWDELAY, rdomain = 0;
43
44	TAILQ_FOREACH(lap, &lconf->listen_addrs, entry) {
45		switch (lap->sa.ss_family) {
46		case AF_UNSPEC:
47			if (getifaddrs(&ifa) == -1)
48				fatal("getifaddrs");
49
50			for (ifap = ifa; ifap != NULL; ifap = ifap->ifa_next) {
51				sa = ifap->ifa_addr;
52				if (sa == NULL || SA_LEN(sa) == 0)
53					continue;
54				if (sa->sa_family == AF_LINK) {
55					ifd = ifap->ifa_data;
56					rdomain = ifd->ifi_rdomain;
57				}
58				if (sa->sa_family != AF_INET &&
59				    sa->sa_family != AF_INET6)
60					continue;
61				if (lap->rtable != -1 && rdomain != lap->rtable)
62					continue;
63
64				if (sa->sa_family == AF_INET &&
65				    ((struct sockaddr_in *)sa)->sin_addr.s_addr ==
66				    INADDR_ANY)
67					continue;
68
69				if (sa->sa_family == AF_INET6) {
70					a6 = ((struct sockaddr_in6 *)sa)->
71					    sin6_addr.s6_addr;
72					if (memcmp(a6, &in6addr_any, sa6len) == 0)
73						continue;
74				}
75
76				if ((la = calloc(1, sizeof(struct listen_addr))) ==
77				    NULL)
78					fatal("setup_listeners calloc");
79
80				memcpy(&la->sa, sa, SA_LEN(sa));
81				la->rtable = rdomain;
82
83				TAILQ_INSERT_TAIL(&lconf->listen_addrs, la, entry);
84			}
85
86			freeifaddrs(ifa);
87		default:
88			continue;
89		}
90	}
91
92
93	for (la = TAILQ_FIRST(&lconf->listen_addrs); la; ) {
94		switch (la->sa.ss_family) {
95		case AF_INET:
96			if (((struct sockaddr_in *)&la->sa)->sin_port == 0)
97				((struct sockaddr_in *)&la->sa)->sin_port =
98				    se->s_port;
99			break;
100		case AF_INET6:
101			if (((struct sockaddr_in6 *)&la->sa)->sin6_port == 0)
102				((struct sockaddr_in6 *)&la->sa)->sin6_port =
103				    se->s_port;
104			break;
105		case AF_UNSPEC:
106			nla = TAILQ_NEXT(la, entry);
107			TAILQ_REMOVE(&lconf->listen_addrs, la, entry);
108			free(la);
109			la = nla;
110			continue;
111		default:
112			fatalx("king bula sez: af borked");
113		}
114
115		log_info("listening on %s %s",
116		    log_sockaddr((struct sockaddr *)&la->sa),
117		    print_rtable(la->rtable));
118
119		if ((la->fd = socket(la->sa.ss_family, SOCK_DGRAM, 0)) == -1)
120			fatal("socket");
121
122		if (la->sa.ss_family == AF_INET && setsockopt(la->fd,
123		    IPPROTO_IP, IP_TOS, &tos, sizeof(tos)) == -1)
124			log_warn("setsockopt IPTOS_LOWDELAY");
125
126		if (la->rtable != -1 &&
127		    setsockopt(la->fd, SOL_SOCKET, SO_RTABLE, &la->rtable,
128		    sizeof(la->rtable)) == -1)
129			fatal("setup_listeners setsockopt SO_RTABLE");
130
131		if (bind(la->fd, (struct sockaddr *)&la->sa,
132		    SA_LEN((struct sockaddr *)&la->sa)) == -1) {
133			log_warn("bind on %s failed, skipping",
134			    log_sockaddr((struct sockaddr *)&la->sa));
135			close(la->fd);
136			nla = TAILQ_NEXT(la, entry);
137			TAILQ_REMOVE(&lconf->listen_addrs, la, entry);
138			free(la);
139			la = nla;
140			continue;
141		}
142		new_cnt++;
143		la = TAILQ_NEXT(la, entry);
144	}
145
146	*cnt = new_cnt;
147
148	return (0);
149}
150
151int
152server_dispatch(int fd, struct ntpd_conf *lconf)
153{
154	ssize_t			 size;
155	double			 rectime;
156	struct sockaddr_storage	 fsa;
157	socklen_t		 fsa_len;
158	struct ntp_msg		 query, reply;
159	char			 buf[NTP_MSGSIZE];
160
161	fsa_len = sizeof(fsa);
162	if ((size = recvfrom(fd, &buf, sizeof(buf), 0,
163	    (struct sockaddr *)&fsa, &fsa_len)) == -1) {
164		if (errno == EHOSTUNREACH || errno == EHOSTDOWN ||
165		    errno == ENETUNREACH || errno == ENETDOWN) {
166			log_warn("recvfrom %s",
167			    log_sockaddr((struct sockaddr *)&fsa));
168			return (0);
169		} else
170			fatal("recvfrom");
171	}
172
173	rectime = gettime_corrected();
174
175	if (ntp_getmsg((struct sockaddr *)&fsa, buf, size, &query) == -1)
176		return (0);
177
178	memset(&reply, 0, sizeof(reply));
179	if (lconf->status.synced)
180		reply.status = lconf->status.leap;
181	else
182		reply.status = LI_ALARM;
183	reply.status |= (query.status & VERSIONMASK);
184	if ((query.status & MODEMASK) == MODE_CLIENT)
185		reply.status |= MODE_SERVER;
186	else if ((query.status & MODEMASK) == MODE_SYM_ACT)
187		reply.status |= MODE_SYM_PAS;
188	else /* ignore packets of different type (e.g. bcast) */
189		return (0);
190
191	reply.stratum =	lconf->status.stratum;
192	reply.ppoll = query.ppoll;
193	reply.precision = lconf->status.precision;
194	reply.rectime = d_to_lfp(rectime);
195	reply.reftime = d_to_lfp(lconf->status.reftime);
196	reply.xmttime = d_to_lfp(gettime_corrected());
197	reply.orgtime = query.xmttime;
198	reply.rootdelay = d_to_sfp(lconf->status.rootdelay);
199	reply.refid = lconf->status.refid;
200
201	ntp_sendmsg(fd, (struct sockaddr *)&fsa, &reply);
202	return (0);
203}
204