xref: /netbsd-src/sbin/mount_portal/activate.c (revision 8e2fe69844c96cc22071335604a9d91f634f8d41)
1 /*	$NetBSD: activate.c,v 1.15 2009/04/11 07:36:43 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software donated to Berkeley by
8  * Jan-Simon Pendry.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	from: Id: activate.c,v 1.2 1992/05/27 07:09:27 jsp Exp
35  *	@(#)activate.c	8.3 (Berkeley) 4/28/95
36  */
37 
38 #include <sys/cdefs.h>
39 #ifndef lint
40 __RCSID("$NetBSD: activate.c,v 1.15 2009/04/11 07:36:43 lukem Exp $");
41 #endif /* not lint */
42 
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <unistd.h>
46 #include <string.h>
47 #include <errno.h>
48 #include <signal.h>
49 #include <sys/types.h>
50 #include <sys/param.h>
51 #include <sys/socket.h>
52 #include <sys/un.h>
53 #include <sys/syslog.h>
54 #include <sys/uio.h>
55 
56 #include "portald.h"
57 
58 static	int	get_request(int, struct portal_cred *, char *, size_t);
59 static	void	send_reply(int, int, int);
60 
61 /*
62  * Scan the providers list and call the
63  * appropriate function.
64  */
65 int
activate_argv(struct portal_cred * pcr,char * key,char ** v,int * fdp)66 activate_argv(struct portal_cred *pcr, char *key, char **v, int *fdp)
67 {
68 	provider *pr;
69 
70 	for (pr = providers; pr->pr_match; pr++)
71 		if (strcmp(v[0], pr->pr_match) == 0)
72 			return ((*pr->pr_func)(pcr, key, v, fdp));
73 
74 	return (ENOENT);
75 }
76 
77 static int
get_request(int so,struct portal_cred * pcr,char * key,size_t klen)78 get_request(int so, struct portal_cred *pcr, char *key, size_t klen)
79 {
80 	struct iovec iov[2];
81 	struct msghdr msg;
82 	ssize_t n;
83 
84 	iov[0].iov_base = (caddr_t) pcr;
85 	iov[0].iov_len = sizeof(*pcr);
86 	iov[1].iov_base = key;
87 	iov[1].iov_len = klen;
88 
89 	memset(&msg, 0, sizeof(msg));
90 	msg.msg_iov = iov;
91 	msg.msg_iovlen = 2;
92 
93 	n = recvmsg(so, &msg, 0);
94 	if (n < 0)
95 		return (errno);
96 
97 	if (n <= (ssize_t)sizeof(*pcr))
98 		return (EINVAL);
99 
100 	n -= sizeof(*pcr);
101 	key[n] = '\0';
102 
103 	return (0);
104 }
105 
106 static void
send_reply(int so,int fd,int error)107 send_reply(int so, int fd, int error)
108 {
109 	int n;
110 	struct iovec iov;
111 	struct msghdr msg;
112 	void *ctl = NULL;
113 	struct cmsghdr *cmsg;
114 	int *files;
115 	socklen_t cmsgsize;
116 
117 	/*
118 	 * Line up error code.  Don't worry about byte ordering
119 	 * because we must be sending to the local machine.
120 	 */
121 	iov.iov_base = (caddr_t) &error;
122 	iov.iov_len = sizeof(error);
123 
124 	/*
125 	 * Build a msghdr
126 	 */
127 	memset(&msg, 0, sizeof(msg));
128 	msg.msg_iov = &iov;
129 	msg.msg_iovlen = 1;
130 
131 	/*
132 	 * If there is a file descriptor to send then
133 	 * construct a suitable rights control message.
134 	 */
135 	if (fd >= 0) {
136 		cmsgsize = CMSG_LEN(sizeof(*files));
137 
138 		ctl = malloc(cmsgsize);
139 		if (ctl == NULL) {
140 			syslog(LOG_WARNING, "malloc control message: %m");
141 			return;
142 		}
143 		memset(ctl, 0, cmsgsize);
144 
145 		cmsg = (struct cmsghdr *) ctl;
146 		cmsg->cmsg_len = CMSG_LEN(sizeof(int));
147 		cmsg->cmsg_level = SOL_SOCKET;
148 		cmsg->cmsg_type = SCM_RIGHTS;
149 
150 		files = (int *)CMSG_DATA(cmsg);
151 		files[0] = fd;
152 
153 		msg.msg_control = ctl;
154 		msg.msg_controllen = cmsgsize;
155 	}
156 
157 	/*
158 	 * Send to kernel...
159 	 */
160 	if ((n = sendmsg(so, &msg, MSG_EOR)) < 0)
161 		syslog(LOG_WARNING, "send: %m");
162 #ifdef DEBUG
163 	fprintf(stderr, "sent %d bytes\n", n);
164 #endif
165 	sleep(1);	/*XXX*/
166 #ifdef notdef
167 	if (shutdown(so, 2) < 0)
168 		syslog(LOG_WARNING, "shutdown: %m");
169 #endif
170 	/*
171 	 * Throw away the open file descriptor and control
172 	 * message buffer.
173 	 */
174 	if (fd >= 0)
175 		(void) close(fd);
176 	if (ctl != NULL)
177 		free(ctl);
178 }
179 
180 void
activate(qelem * q,int so)181 activate(qelem *q, int so)
182 {
183 	struct portal_cred pcred;
184 	char key[MAXPATHLEN+1];
185 	int error;
186 	char **v;
187 	int fd = -1;
188 
189 	/*
190 	 * Read the key from the socket
191 	 */
192 	error = get_request(so, &pcred, key, sizeof(key));
193 	if (error) {
194 		syslog(LOG_WARNING, "activate: recvmsg: %m");
195 		goto drop;
196 	}
197 
198 #ifdef DEBUG
199 	fprintf(stderr, "lookup key %s\n", key);
200 #endif
201 
202 	/*
203 	 * Find a match in the configuration file
204 	 */
205 	v = conf_match(q, key);
206 
207 	/*
208 	 * If a match existed, then find an appropriate portal
209 	 * otherwise simply return ENOENT.
210 	 */
211 	if (v) {
212 		error = activate_argv(&pcred, key, v, &fd);
213 		if (error)
214 			fd = -1;
215 		else if (fd < 0)
216 			error = -1;
217 	} else
218 		error = ENOENT;
219 
220 	if (error >= 0)
221 		send_reply(so, fd, error);
222 
223 drop:;
224 	close(so);
225 }
226