1/*	$NetBSD: check_bound.c,v 1.4 2007/05/13 20:03:46 christos Exp $	*/
2
3/*
4 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5 * unrestricted use provided that this legend is included on all tape
6 * media and as a part of the software program in whole or part.  Users
7 * may copy or modify Sun RPC without charge, but are not authorized
8 * to license or distribute it to anyone else except as part of a product or
9 * program developed by the user.
10 *
11 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14 *
15 * Sun RPC is provided with no support and without any obligation on the
16 * part of Sun Microsystems, Inc. to assist in its use, correction,
17 * modification or enhancement.
18 *
19 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21 * OR ANY PART THEREOF.
22 *
23 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24 * or profits or other special, indirect and consequential damages, even if
25 * Sun has been advised of the possibility of such damages.
26 *
27 * Sun Microsystems, Inc.
28 * 2550 Garcia Avenue
29 * Mountain View, California  94043
30 */
31/*
32 * Copyright (c) 1986 - 1991 by Sun Microsystems, Inc.
33 */
34
35/* #ident	"@(#)check_bound.c	1.15	93/07/05 SMI" */
36
37#if 0
38#ifndef lint
39static	char sccsid[] = "@(#)check_bound.c 1.11 89/04/21 Copyr 1989 Sun Micro";
40#endif
41#endif
42
43/*
44 * check_bound.c
45 * Checks to see whether the program is still bound to the
46 * claimed address and returns the univeral merged address
47 *
48 */
49
50#include <sys/types.h>
51#include <sys/socket.h>
52#include <rpc/rpc.h>
53#include <stdio.h>
54#include <netconfig.h>
55#include <syslog.h>
56#include <string.h>
57#include <unistd.h>
58#include <stdlib.h>
59
60#include "rpcbind.h"
61
62struct fdlist {
63	int fd;
64	struct netconfig *nconf;
65	struct fdlist *next;
66	int check_binding;
67};
68
69static struct fdlist *fdhead;	/* Link list of the check fd's */
70static struct fdlist *fdtail;
71static const char emptystring[] = "";
72
73static bool_t check_bound(struct fdlist *, const char *uaddr);
74
75/*
76 * Returns 1 if the given address is bound for the given addr & transport
77 * For all error cases, we assume that the address is bound
78 * Returns 0 for success.
79 */
80static bool_t
81check_bound(struct fdlist *fdl, const char *uaddr)
82{
83	int fd;
84	struct netbuf *na;
85	int ans;
86
87	if (fdl->check_binding == FALSE)
88		return (TRUE);
89
90	na = uaddr2taddr(fdl->nconf, uaddr);
91	if (!na)
92		return (TRUE); /* punt, should never happen */
93
94	fd = __rpc_nconf2fd(fdl->nconf);
95	if (fd < 0) {
96		free(na);
97		return (TRUE);
98	}
99
100	ans = bind(fd, (struct sockaddr *)na->buf, na->len);
101
102	close(fd);
103	free(na);
104
105	return (ans == 0 ? FALSE : TRUE);
106}
107
108int
109add_bndlist(struct netconfig *nconf, struct netbuf *baddr)
110{
111	struct fdlist *fdl;
112	struct netconfig *newnconf;
113
114	newnconf = getnetconfigent(nconf->nc_netid);
115	if (newnconf == NULL)
116		return (-1);
117	fdl = (struct fdlist *)malloc((u_int)sizeof (struct fdlist));
118	if (fdl == NULL) {
119		freenetconfigent(newnconf);
120		syslog(LOG_ERR, "no memory!");
121		return (-1);
122	}
123	fdl->nconf = newnconf;
124	fdl->next = NULL;
125	if (fdhead == NULL) {
126		fdhead = fdl;
127		fdtail = fdl;
128	} else {
129		fdtail->next = fdl;
130		fdtail = fdl;
131	}
132	/* XXX no bound checking for now */
133	fdl->check_binding = FALSE;
134
135	return 0;
136}
137
138bool_t
139is_bound(const char *netid, const char *uaddr)
140{
141	struct fdlist *fdl;
142
143	for (fdl = fdhead; fdl; fdl = fdl->next)
144		if (strcmp(fdl->nconf->nc_netid, netid) == 0)
145			break;
146	if (fdl == NULL)
147		return (TRUE);
148	return (check_bound(fdl, uaddr));
149}
150
151/*
152 * Returns NULL if there was some system error.
153 * Returns "" if the address was not bound, i.e the server crashed.
154 * Returns the merged address otherwise.
155 */
156char *
157mergeaddr(SVCXPRT *xprt, char *netid, char *uaddr, char *saddr)
158{
159	struct fdlist *fdl;
160	char *c_uaddr, *s_uaddr, *m_uaddr, *allocated_uaddr = NULL;
161
162	for (fdl = fdhead; fdl; fdl = fdl->next)
163		if (strcmp(fdl->nconf->nc_netid, netid) == 0)
164			break;
165	if (fdl == NULL)
166		return (NULL);
167	if (check_bound(fdl, uaddr) == FALSE)
168		/* that server died */
169		return strdup(emptystring);
170	/*
171	 * If saddr is not NULL, the remote client may have included the
172	 * address by which it contacted us.  Use that for the "client" uaddr,
173	 * otherwise use the info from the SVCXPRT.
174	 */
175	if (saddr != NULL) {
176		c_uaddr = saddr;
177	} else {
178		c_uaddr = taddr2uaddr(fdl->nconf, svc_getrpccaller(xprt));
179		if (c_uaddr == NULL) {
180			syslog(LOG_ERR, "taddr2uaddr failed for %s",
181				fdl->nconf->nc_netid);
182			return (NULL);
183		}
184		allocated_uaddr = c_uaddr;
185	}
186
187#ifdef RPCBIND_DEBUG
188	if (debugging) {
189		if (saddr == NULL) {
190			fprintf(stderr, "mergeaddr: client uaddr = %s\n",
191			    c_uaddr);
192		} else {
193			fprintf(stderr, "mergeaddr: contact uaddr = %s\n",
194			    c_uaddr);
195		}
196	}
197#endif
198	s_uaddr = uaddr;
199	/*
200	 * This is all we should need for IP 4 and 6
201	 */
202	m_uaddr = addrmerge(svc_getrpccaller(xprt), s_uaddr, c_uaddr, netid);
203#ifdef RPCBIND_DEBUG
204	if (debugging)
205		fprintf(stderr, "mergeaddr: uaddr = %s, merged uaddr = %s\n",
206				uaddr, m_uaddr);
207#endif
208	if (allocated_uaddr != NULL)
209		free(allocated_uaddr);
210	return (m_uaddr);
211}
212
213/*
214 * Returns a netconf structure from its internal list.  This
215 * structure should not be freed.
216 */
217struct netconfig *
218rpcbind_get_conf(const char *netid)
219{
220	struct fdlist *fdl;
221
222	for (fdl = fdhead; fdl; fdl = fdl->next)
223		if (strcmp(fdl->nconf->nc_netid, netid) == 0)
224			break;
225	if (fdl == NULL)
226		return (NULL);
227	return (fdl->nconf);
228}
229