xref: /illumos-gate/usr/src/cmd/rpcbind/rpcb_check.c (revision 581cede61ac9c14d8d4ea452562a567189eead78)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Auxiliary routines to shield off random internet hosts and to report
23  * service requests (verbose mode only) or violations (always).
24  *
25  * This code was extensively modifed from a version authored by:
26  *
27  * Wietse Venema, Eindhoven University of Technology, The Netherlands
28  * and distributed as "rpcbind 2.1".
29  *
30  * Sun was granted permission to use, modify, including make
31  * derivatives of, copy, reproduce and distribute this code.c in both
32  * binary and source forms, directly and indirectly.
33  *
34  * Modified for bundling with Solaris and IPv6.
35  *
36  * Solaris specific modifcations made are:
37  *
38  *	Double fork() logging replaced with qsyslog();
39  *	Connection refusals are flagged with svcerr_auth(); this
40  *	aids in quicker diagnosability of misconfigurations and quicker
41  *	failures for /net automounts;
42  *	Single function for pmap* and rpcb*;
43  *	Local transport checks made using localxprt().
44  *
45  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
46  * Use is subject to license terms.
47  */
48 
49 #pragma ident	"%Z%%M%	%I%	%E% SMI"
50 
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <unistd.h>
54 #include <string.h>
55 #include <syslog.h>
56 #include <errno.h>
57 #include <netconfig.h>
58 #include <netdb.h>
59 #include <netdir.h>
60 #include <arpa/inet.h>
61 #include <netinet/in.h>
62 #include <rpc/rpc.h>
63 #include <rpc/pmap_prot.h>
64 #include <rpc/rpcb_prot.h>
65 
66 #include "rpcbind.h"
67 
68 /*
69  * These are globally visible so that they can be modified by the wrapper's
70  * language extension routines.
71  */
72 int allow_severity = LOG_INFO;
73 int deny_severity = LOG_WARNING;
74 
75 extern int hosts_ctl();
76 
77 /*
78  * "inet_ntoa/inet_pton" for struct sockaddr_gen
79  */
80 static const char *
81 sgen_toa(struct sockaddr_gen *addr)
82 {
83 	static char buf[INET6_ADDRSTRLEN];
84 	return (inet_ntop(SGFAM(addr), SGADDRP(addr), buf, sizeof (buf)));
85 }
86 
87 /*
88  * find_procname - map rpcb/pmap procedure number to name
89  */
90 static const char *
91 find_procname(rpcproc_t procnum, boolean_t pm)
92 {
93 	static char procbuf[6 + 3 * sizeof (ulong_t)];
94 	struct proc_map {
95 		rpcproc_t code;
96 		const char *proc;
97 	};
98 	static struct proc_map pmapmap[] = {
99 		PMAPPROC_CALLIT,	"callit",
100 		PMAPPROC_DUMP,		"dump",
101 		PMAPPROC_GETPORT,	"getport",
102 		PMAPPROC_SET,		"set",
103 		PMAPPROC_UNSET,		"unset",
104 		NULLPROC,		"null",
105 	};
106 	static struct proc_map rpcbmap[] = {
107 		RPCBPROC_SET,		"set",
108 		RPCBPROC_UNSET,		"unset",
109 		RPCBPROC_GETADDR,	"getaddr",
110 		RPCBPROC_DUMP,		"dump",
111 		RPCBPROC_CALLIT,	"callit",
112 		RPCBPROC_GETTIME,	"gettime",
113 		RPCBPROC_UADDR2TADDR,	"uaddr2taddr",
114 		RPCBPROC_TADDR2UADDR,	"taddr2uaddr",
115 		RPCBPROC_GETVERSADDR,	"getversaddr",
116 		RPCBPROC_INDIRECT,	"indirect",
117 		RPCBPROC_GETADDRLIST,	"getaddrlist",
118 		RPCBPROC_GETSTAT,	"getstat",
119 		NULLPROC,		"null",
120 	};
121 
122 	int nitems, i;
123 	struct proc_map *procp;
124 
125 	if (pm) {
126 		procp = pmapmap;
127 		nitems = sizeof (pmapmap)/sizeof (struct proc_map);
128 	} else {
129 		procp = rpcbmap;
130 		nitems = sizeof (rpcbmap)/sizeof (struct proc_map);
131 	}
132 
133 	for (i = 0; i < nitems; i++) {
134 		if (procp[i].code == procnum)
135 			return (procp[i].proc);
136 	}
137 	(void) snprintf(procbuf, sizeof (procbuf), "%s-%lu",
138 		pm ? "pmap" : "rpcb", (ulong_t)procnum);
139 	return (procbuf);
140 }
141 
142 /*
143  * find_progname - map rpc program number to name.
144  */
145 static const char *
146 find_progname(rpcprog_t prognum)
147 {
148 	static char progbuf[1 + 3 * sizeof (ulong_t)];
149 
150 	if (prognum == 0)
151 		return ("");
152 
153 	/*
154 	 * The original code contained a call to "getrpcbynumber()";
155 	 * this call was removed because it may cause a call to a
156 	 * nameservice.
157 	 */
158 
159 	(void) snprintf(progbuf, sizeof (progbuf), "%lu", (ulong_t)prognum);
160 	return (progbuf);
161 }
162 
163 /*
164  * rpcb_log - log request for service
165  */
166 void
167 rpcb_log(boolean_t verdict, SVCXPRT *transp, rpcproc_t proc, rpcprog_t prog,
168     boolean_t pm)
169 {
170 	struct netconfig *conf;
171 	const char *client = "unknown";
172 	char *uaddr;
173 	char buf[BUFSIZ];
174 
175 	/*
176 	 * Transform the transport address into something printable.
177 	 */
178 	if ((conf = rpcbind_get_conf(transp->xp_netid)) == 0) {
179 		syslog(LOG_WARNING,
180 		    "unknown transport (rpcbind_get_conf failed)");
181 	} else if (strcmp(conf->nc_protofmly, "inet") == 0 ||
182 	    strcmp(conf->nc_protofmly, "inet6") == 0) {
183 		client = sgen_toa(svc_getgencaller(transp));
184 	} else if ((uaddr = taddr2uaddr(conf, &(transp->xp_rtaddr))) == NULL) {
185 		syslog(LOG_WARNING, "unknown address (taddr2uaddr failed)");
186 	} else {
187 		(void) snprintf(buf, sizeof (buf), "%s(%s)",
188 		    conf->nc_protofmly, uaddr);
189 		free(uaddr);
190 		client = buf;
191 	}
192 	qsyslog(verdict ? allow_severity : deny_severity,
193 	    "%sconnect from %s to %s(%s)", verdict ? "" : "refused ",
194 	    client, find_procname(proc, pm), find_progname(prog));
195 }
196 
197 /*
198  * rpcb_check; the rpcbind/portmap access check function.
199  */
200 boolean_t
201 rpcb_check(SVCXPRT *transp, rpcproc_t procnum, boolean_t ispmap)
202 {
203 	struct netconfig *conf;
204 	boolean_t res = B_TRUE;
205 
206 	if ((conf = rpcbind_get_conf(transp->xp_netid)) == 0) {
207 		syslog(LOG_ERR,
208 		    "rpcbind_get_conf failed: no client address checks");
209 		return (B_TRUE);
210 	}
211 
212 	/*
213 	 * Require IPv4 for pmap calls; they're not defined for anything else.
214 	 */
215 	if (ispmap && strcmp(conf->nc_protofmly, "inet") != 0) {
216 		res = B_FALSE;
217 	} else if (strcmp(conf->nc_protofmly, "inet") == 0 ||
218 	    strcmp(conf->nc_protofmly, "inet6") == 0) {
219 		const char *addr_string = sgen_toa(svc_getgencaller(transp));
220 
221 		if (!localxprt(transp, ispmap) &&
222 		    (local_only ||
223 		    hosts_ctl("rpcbind", addr_string, addr_string, "") == 0)) {
224 			res = B_FALSE;
225 		}
226 	}
227 out:
228 	if (!res)
229 		svcerr_auth(transp, AUTH_FAILED);
230 
231 	if (verboselog || !res)
232 		rpcb_log(res, transp, procnum, 0, ispmap);
233 
234 	return (res);
235 }
236