1/*	$NetBSD: check_bound.c,v 1.2 2000/06/22 08:09:26 fvdl Exp $	*/
2/*	$FreeBSD$ */
3
4/*-
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Copyright (c) 2009, Sun Microsystems, Inc.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions are met:
12 * - Redistributions of source code must retain the above copyright notice,
13 *   this list of conditions and the following disclaimer.
14 * - Redistributions in binary form must reproduce the above copyright notice,
15 *   this list of conditions and the following disclaimer in the documentation
16 *   and/or other materials provided with the distribution.
17 * - Neither the name of Sun Microsystems, Inc. nor the names of its
18 *   contributors may be used to endorse or promote products derived
19 *   from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
25 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 */
33/*
34 * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
35 */
36
37/* #ident	"@(#)check_bound.c	1.15	93/07/05 SMI" */
38
39#if 0
40#ifndef lint
41static	char sccsid[] = "@(#)check_bound.c 1.11 89/04/21 Copyr 1989 Sun Micro";
42#endif
43#endif
44
45/*
46 * check_bound.c
47 * Checks to see whether the program is still bound to the
48 * claimed address and returns the universal merged address
49 *
50 */
51
52#include <sys/types.h>
53#include <sys/socket.h>
54#include <rpc/rpc.h>
55#include <rpc/svc_dg.h>
56#include <netconfig.h>
57#include <syslog.h>
58#include <string.h>
59#include <unistd.h>
60#include <stdlib.h>
61
62#include "rpcbind.h"
63
64struct fdlist {
65	int fd;
66	struct netconfig *nconf;
67	struct fdlist *next;
68	int check_binding;
69};
70
71static struct fdlist *fdhead;	/* Link list of the check fd's */
72static struct fdlist *fdtail;
73static char *nullstring = "";
74
75static bool_t check_bound(struct fdlist *, char *uaddr);
76
77/*
78 * Returns 1 if the given address is bound for the given addr & transport
79 * For all error cases, we assume that the address is bound
80 * Returns 0 for success.
81 */
82static bool_t
83check_bound(struct fdlist *fdl, char *uaddr)
84{
85	int fd;
86	struct netbuf *na;
87	int ans;
88
89	if (fdl->check_binding == FALSE)
90		return (TRUE);
91
92	na = uaddr2taddr(fdl->nconf, uaddr);
93	if (!na)
94		return (TRUE); /* punt, should never happen */
95
96	fd = __rpc_nconf2fd(fdl->nconf);
97	if (fd < 0) {
98		free(na->buf);
99		free(na);
100		return (TRUE);
101	}
102
103	ans = bind(fd, (struct sockaddr *)na->buf, na->len);
104
105	close(fd);
106	free(na->buf);
107	free(na);
108
109	return (ans == 0 ? FALSE : TRUE);
110}
111
112int
113add_bndlist(struct netconfig *nconf, struct netbuf *baddr __unused)
114{
115	struct fdlist *fdl;
116	struct netconfig *newnconf;
117
118	newnconf = getnetconfigent(nconf->nc_netid);
119	if (newnconf == NULL)
120		return (-1);
121	fdl = malloc(sizeof (struct fdlist));
122	if (fdl == NULL) {
123		freenetconfigent(newnconf);
124		syslog(LOG_ERR, "no memory!");
125		return (-1);
126	}
127	fdl->nconf = newnconf;
128	fdl->next = NULL;
129	if (fdhead == NULL) {
130		fdhead = fdl;
131		fdtail = fdl;
132	} else {
133		fdtail->next = fdl;
134		fdtail = fdl;
135	}
136	/* XXX no bound checking for now */
137	fdl->check_binding = FALSE;
138
139	return 0;
140}
141
142bool_t
143is_bound(char *netid, char *uaddr)
144{
145	struct fdlist *fdl;
146
147	for (fdl = fdhead; fdl; fdl = fdl->next)
148		if (strcmp(fdl->nconf->nc_netid, netid) == 0)
149			break;
150	if (fdl == NULL)
151		return (TRUE);
152	return (check_bound(fdl, uaddr));
153}
154
155/*
156 * Returns NULL if there was some system error.
157 * Returns "" if the address was not bound, i.e the server crashed.
158 * Returns the merged address otherwise.
159 */
160char *
161mergeaddr(SVCXPRT *xprt, char *netid, char *uaddr, char *saddr)
162{
163	struct fdlist *fdl;
164	struct svc_dg_data *dg_data;
165	char *c_uaddr, *s_uaddr, *m_uaddr, *allocated_uaddr = NULL;
166
167	for (fdl = fdhead; fdl; fdl = fdl->next)
168		if (strcmp(fdl->nconf->nc_netid, netid) == 0)
169			break;
170	if (fdl == NULL)
171		return (NULL);
172	if (check_bound(fdl, uaddr) == FALSE)
173		/* that server died */
174		return (nullstring);
175	/*
176	 * Try to determine the local address on which the client contacted us,
177	 * so we can send a reply from the same address.  If it's unknown, then
178	 * try to determine which address the client used, and pick a nearby
179	 * local address.
180	 *
181	 * If saddr is not NULL, the remote client may have included the
182	 * address by which it contacted us.  Use that for the "client" uaddr,
183	 * otherwise use the info from the SVCXPRT.
184	 */
185	dg_data = (struct svc_dg_data*)xprt->xp_p2;
186	if (dg_data != NULL && dg_data->su_srcaddr.buf != NULL) {
187		c_uaddr = taddr2uaddr(fdl->nconf, &dg_data->su_srcaddr);
188		allocated_uaddr = c_uaddr;
189	}
190	else if (saddr != NULL) {
191		c_uaddr = saddr;
192	} else {
193		c_uaddr = taddr2uaddr(fdl->nconf, svc_getrpccaller(xprt));
194		allocated_uaddr = c_uaddr;
195	}
196	if (c_uaddr == NULL) {
197		syslog(LOG_ERR, "taddr2uaddr failed for %s",
198			fdl->nconf->nc_netid);
199		return (NULL);
200	}
201
202#ifdef ND_DEBUG
203	if (debugging) {
204		if (saddr == NULL) {
205			fprintf(stderr, "mergeaddr: client uaddr = %s\n",
206			    c_uaddr);
207		} else {
208			fprintf(stderr, "mergeaddr: contact uaddr = %s\n",
209			    c_uaddr);
210		}
211	}
212#endif
213	s_uaddr = uaddr;
214	/*
215	 * This is all we should need for IP 4 and 6
216	 */
217	m_uaddr = addrmerge(svc_getrpccaller(xprt), s_uaddr, c_uaddr, netid);
218#ifdef ND_DEBUG
219	if (debugging)
220		fprintf(stderr, "mergeaddr: uaddr = %s, merged uaddr = %s\n",
221				uaddr, m_uaddr);
222#endif
223	free(allocated_uaddr);
224	return (m_uaddr);
225}
226
227/*
228 * Returns a netconf structure from its internal list.  This
229 * structure should not be freed.
230 */
231struct netconfig *
232rpcbind_get_conf(const char *netid)
233{
234	struct fdlist *fdl;
235
236	for (fdl = fdhead; fdl; fdl = fdl->next)
237		if (strcmp(fdl->nconf->nc_netid, netid) == 0)
238			break;
239	if (fdl == NULL)
240		return (NULL);
241	return (fdl->nconf);
242}
243