1/*-
2 * Copyright (c) 2009 Rick Macklem, University of Guelph
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD$");
30
31#include <sys/param.h>
32#include <sys/ioctl.h>
33#include <sys/linker.h>
34#include <sys/module.h>
35#include <sys/mount.h>
36#include <sys/socket.h>
37#include <sys/socketvar.h>
38#include <sys/stat.h>
39#include <sys/ucred.h>
40#include <sys/uio.h>
41#include <sys/vnode.h>
42#include <sys/wait.h>
43
44#include <nfs/nfssvc.h>
45
46#include <rpc/rpc.h>
47
48#include <fs/nfs/rpcv2.h>
49#include <fs/nfs/nfsproto.h>
50#include <fs/nfs/nfskpiport.h>
51#include <fs/nfs/nfs.h>
52
53#include <err.h>
54#include <errno.h>
55#include <fcntl.h>
56#include <grp.h>
57#include <netdb.h>
58#include <pwd.h>
59#include <signal.h>
60#include <stdio.h>
61#include <stdlib.h>
62#include <string.h>
63#include <syslog.h>
64#include <unistd.h>
65
66/* Global defs */
67#ifdef DEBUG
68#define	syslog(e, s)	fprintf(stderr,(s))
69static int	debug = 1;
70#else
71static int	debug = 0;
72#endif
73
74static pid_t	children;
75
76static void	nonfs(int);
77static void	reapchild(int);
78static void	usage(void);
79static void	cleanup(int);
80static void	child_cleanup(int);
81static void	nfscbd_exit(int);
82static void	killchildren(void);
83
84/*
85 * Nfs callback server daemon.
86 *
87 * 1 - do file descriptor and signal cleanup
88 * 2 - fork the nfscbd(s)
89 * 4 - create callback server socket(s)
90 * 5 - set up server socket for rpc
91 *
92 * For connectionless protocols, just pass the socket into the kernel via.
93 * nfssvc().
94 * For connection based sockets, loop doing accepts. When you get a new
95 * socket from accept, pass the msgsock into the kernel via. nfssvc().
96 */
97int
98main(int argc, char *argv[])
99{
100	struct nfscbd_args nfscbdargs;
101	struct nfsd_nfscbd_args nfscbdargs2;
102	struct sockaddr_in inetaddr, inetpeer;
103	fd_set ready, sockbits;
104	int ch, connect_type_cnt, len, maxsock, msgsock, error;
105	int nfssvc_flag, on, sock, tcpsock, ret, mustfreeai = 0;
106	char *cp, princname[128];
107	char myname[MAXHOSTNAMELEN], *myfqdnname = NULL;
108	struct addrinfo *aip, hints;
109	pid_t pid;
110	short myport = NFSV4_CBPORT;
111
112	if (modfind("nfscl") < 0) {
113		/* Not present in kernel, try loading it */
114		if (kldload("nfscl") < 0 ||
115		    modfind("nfscl") < 0)
116			errx(1, "nfscl is not available");
117	}
118	/*
119	 * First, get our fully qualified host name, if possible.
120	 */
121	if (gethostname(myname, MAXHOSTNAMELEN) >= 0) {
122		cp = strchr(myname, '.');
123		if (cp != NULL && *(cp + 1) != '\0') {
124			cp = myname;
125		} else {
126			/*
127			 * No domain on myname, so try looking it up.
128			 */
129			cp = NULL;
130			memset((void *)&hints, 0, sizeof (hints));
131			hints.ai_flags = AI_CANONNAME;
132			error = getaddrinfo(myname, NULL, &hints, &aip);
133			if (error == 0) {
134			    if (aip->ai_canonname != NULL &&
135				(cp = strchr(aip->ai_canonname, '.')) != NULL
136				&& *(cp + 1) != '\0') {
137				    cp = aip->ai_canonname;
138				    mustfreeai = 1;
139			    } else {
140				    freeaddrinfo(aip);
141			    }
142			}
143		}
144		if (cp == NULL)
145			warnx("Can't get fully qualified host name");
146		myfqdnname = cp;
147	}
148
149	princname[0] = '\0';
150#define	GETOPT	"p:P:"
151#define	USAGE	"[ -p port_num ] [ -P client_principal ]"
152	while ((ch = getopt(argc, argv, GETOPT)) != -1)
153		switch (ch) {
154		case 'p':
155			myport = atoi(optarg);
156			if (myport < 1) {
157				warnx("port# non-positive, reset to %d",
158				    NFSV4_CBPORT);
159				myport = NFSV4_CBPORT;
160			}
161			break;
162		case 'P':
163			cp = optarg;
164			if (cp != NULL && strlen(cp) > 0 &&
165			    strlen(cp) < sizeof (princname)) {
166				if (strchr(cp, '@') == NULL &&
167				    myfqdnname != NULL)
168					snprintf(princname, sizeof (princname),
169					    "%s@%s", cp, myfqdnname);
170				else
171					strlcpy(princname, cp,
172					    sizeof (princname));
173			} else {
174				warnx("client princ invalid. ignored\n");
175			}
176			break;
177		default:
178		case '?':
179			usage();
180		};
181	argv += optind;
182	argc -= optind;
183
184	if (argc > 0)
185		usage();
186
187	if (mustfreeai)
188		freeaddrinfo(aip);
189	nfscbdargs2.principal = (const char *)princname;
190	if (debug == 0) {
191		daemon(0, 0);
192		(void)signal(SIGTERM, SIG_IGN);
193		(void)signal(SIGHUP, SIG_IGN);
194		(void)signal(SIGINT, SIG_IGN);
195		(void)signal(SIGQUIT, SIG_IGN);
196	}
197	(void)signal(SIGSYS, nonfs);
198	(void)signal(SIGCHLD, reapchild);
199
200	openlog("nfscbd:", LOG_PID, LOG_DAEMON);
201
202	pid = fork();
203	if (pid < 0) {
204		syslog(LOG_ERR, "fork: %m");
205		nfscbd_exit(1);
206	} else if (pid > 0) {
207		children = pid;
208	} else {
209		(void)signal(SIGUSR1, child_cleanup);
210		setproctitle("server");
211		nfssvc_flag = NFSSVC_NFSCBD;
212		if (nfssvc(nfssvc_flag, &nfscbdargs2) < 0) {
213			syslog(LOG_ERR, "nfssvc: %m");
214			nfscbd_exit(1);
215		}
216		exit(0);
217	}
218	(void)signal(SIGUSR1, cleanup);
219
220	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
221		syslog(LOG_ERR, "can't create udp socket");
222		nfscbd_exit(1);
223	}
224	memset(&inetaddr, 0, sizeof inetaddr);
225	inetaddr.sin_family = AF_INET;
226	inetaddr.sin_addr.s_addr = INADDR_ANY;
227	inetaddr.sin_port = htons(myport);
228	inetaddr.sin_len = sizeof(inetaddr);
229	ret = bind(sock, (struct sockaddr *)&inetaddr, sizeof(inetaddr));
230	/* If bind() fails, this is a restart, so just skip UDP. */
231	if (ret == 0) {
232		len = sizeof(inetaddr);
233		if (getsockname(sock, (struct sockaddr *)&inetaddr, &len) < 0){
234			syslog(LOG_ERR, "can't get bound addr");
235			nfscbd_exit(1);
236		}
237		nfscbdargs.port = ntohs(inetaddr.sin_port);
238		if (nfscbdargs.port != myport) {
239			syslog(LOG_ERR, "BAD PORT#");
240			nfscbd_exit(1);
241		}
242		nfscbdargs.sock = sock;
243		nfscbdargs.name = NULL;
244		nfscbdargs.namelen = 0;
245		if (nfssvc(NFSSVC_CBADDSOCK, &nfscbdargs) < 0) {
246			syslog(LOG_ERR, "can't Add UDP socket");
247			nfscbd_exit(1);
248		}
249	}
250	(void)close(sock);
251
252	/* Now set up the master server socket waiting for tcp connections. */
253	on = 1;
254	FD_ZERO(&sockbits);
255	connect_type_cnt = 0;
256	if ((tcpsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
257		syslog(LOG_ERR, "can't create tcp socket");
258		nfscbd_exit(1);
259	}
260	if (setsockopt(tcpsock,
261	    SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof(on)) < 0)
262		syslog(LOG_ERR, "setsockopt SO_REUSEADDR: %m");
263	/* sin_port is already set */
264	inetaddr.sin_family = AF_INET;
265	inetaddr.sin_addr.s_addr = INADDR_ANY;
266	inetaddr.sin_port = htons(myport);
267	inetaddr.sin_len = sizeof(inetaddr);
268	if (bind(tcpsock,
269	    (struct sockaddr *)&inetaddr, sizeof (inetaddr)) < 0) {
270		syslog(LOG_ERR, "can't bind tcp addr");
271		nfscbd_exit(1);
272	}
273	if (listen(tcpsock, 5) < 0) {
274		syslog(LOG_ERR, "listen failed");
275		nfscbd_exit(1);
276	}
277	FD_SET(tcpsock, &sockbits);
278	maxsock = tcpsock;
279	connect_type_cnt++;
280
281	setproctitle("master");
282
283	/*
284	 * Loop forever accepting connections and passing the sockets
285	 * into the kernel for the mounts.
286	 */
287	for (;;) {
288		ready = sockbits;
289		if (connect_type_cnt > 1) {
290			if (select(maxsock + 1,
291			    &ready, NULL, NULL, NULL) < 1) {
292				syslog(LOG_ERR, "select failed: %m");
293				nfscbd_exit(1);
294			}
295		}
296		if (FD_ISSET(tcpsock, &ready)) {
297			len = sizeof(inetpeer);
298			if ((msgsock = accept(tcpsock,
299			    (struct sockaddr *)&inetpeer, &len)) < 0) {
300				syslog(LOG_ERR, "accept failed: %m");
301				nfscbd_exit(1);
302			}
303			memset(inetpeer.sin_zero, 0,
304			    sizeof (inetpeer.sin_zero));
305			if (setsockopt(msgsock, SOL_SOCKET,
306			    SO_KEEPALIVE, (char *)&on, sizeof(on)) < 0)
307				syslog(LOG_ERR,
308				    "setsockopt SO_KEEPALIVE: %m");
309			nfscbdargs.sock = msgsock;
310			nfscbdargs.name = (caddr_t)&inetpeer;
311			nfscbdargs.namelen = sizeof(inetpeer);
312			nfssvc(NFSSVC_CBADDSOCK, &nfscbdargs);
313			(void)close(msgsock);
314		}
315	}
316}
317
318static void
319usage(void)
320{
321
322	errx(1, "usage: nfscbd %s", USAGE);
323}
324
325static void
326nonfs(int signo __unused)
327{
328	syslog(LOG_ERR, "missing system call: NFS not available");
329}
330
331static void
332reapchild(int signo __unused)
333{
334	pid_t pid;
335
336	while ((pid = wait3(NULL, WNOHANG, NULL)) > 0) {
337		if (pid == children)
338			children = -1;
339	}
340}
341
342static void
343killchildren(void)
344{
345
346	if (children > 0)
347		kill(children, SIGKILL);
348}
349
350/*
351 * Cleanup master after SIGUSR1.
352 */
353static void
354cleanup(int signo __unused)
355{
356	nfscbd_exit(0);
357}
358
359/*
360 * Cleanup child after SIGUSR1.
361 */
362static void
363child_cleanup(int signo __unused)
364{
365	exit(0);
366}
367
368static void
369nfscbd_exit(int status __unused)
370{
371	killchildren();
372	exit(status);
373}
374