nfscbd.c revision 192811 
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: head/usr.sbin/nfscbd/nfscbd.c 192811 2009-05-26 15:19:04Z rmacklem $");
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/nfsproto.h>
49#include <fs/nfs/nfskpiport.h>
50#include <fs/nfs/nfs.h>
51#include <fs/nfs/rpcv2.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))
69int	debug = 1;
70#else
71int	debug = 0;
72#endif
73
74pid_t children;
75
76void	nonfs(int);
77void	reapchild(int);
78void	usage(void);
79void	cleanup(int);
80void	child_cleanup(int);
81void	nfscbd_exit(int);
82void	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[], char **envp)
99{
100	struct group *grp;
101	struct nfscbd_args nfscbdargs;
102	struct nfsd_nfscbd_args nfscbdargs2;
103	struct passwd *pwd;
104	struct ucred *cr;
105	struct sockaddr_in inetaddr, inetpeer;
106	struct timeval ktv;
107	fd_set ready, sockbits;
108	int ch, connect_type_cnt, i, len, maxsock, msgsock, error;
109	int nfssvc_flag, on, sock, tcpsock, ret, mustfreeai = 0;
110	char *cp, **cpp, princname[128];
111	char myname[MAXHOSTNAMELEN], *myfqdnname = NULL;
112	struct addrinfo *aip, hints;
113	pid_t pid;
114	sigset_t signew;
115	short myport = NFSV4_CBPORT;
116
117	if (modfind("nfscl") < 0) {
118		/* Not present in kernel, try loading it */
119		if (kldload("nfscl") < 0 ||
120		    modfind("nfscl") < 0)
121			errx(1, "nfscl is not available");
122	}
123	/*
124	 * First, get our fully qualified host name, if possible.
125	 */
126	if (gethostname(myname, MAXHOSTNAMELEN) >= 0) {
127		cp = strchr(myname, '.');
128		if (cp != NULL && *(cp + 1) != '\0') {
129			cp = myname;
130		} else {
131			/*
132			 * No domain on myname, so try looking it up.
133			 */
134			cp = NULL;
135			memset((void *)&hints, 0, sizeof (hints));
136			hints.ai_flags = AI_CANONNAME;
137			error = getaddrinfo(myname, NULL, &hints, &aip);
138			if (error == 0) {
139			    if (aip->ai_canonname != NULL &&
140				(cp = strchr(aip->ai_canonname, '.')) != NULL
141				&& *(cp + 1) != '\0') {
142				    cp = aip->ai_canonname;
143				    mustfreeai = 1;
144			    } else {
145				    freeaddrinfo(aip);
146			    }
147			}
148		}
149		if (cp == NULL)
150			warnx("Can't get fully qualified host name");
151		myfqdnname = cp;
152	}
153
154	princname[0] = '\0';
155#define	GETOPT	"p:P:"
156#define	USAGE	"[ -p port_num ] [ -P client_principal ]"
157	while ((ch = getopt(argc, argv, GETOPT)) != -1)
158		switch (ch) {
159		case 'p':
160			myport = atoi(optarg);
161			if (myport < 1) {
162				warnx("port# non-positive, reset to %d",
163				    NFSV4_CBPORT);
164				myport = NFSV4_CBPORT;
165			}
166			break;
167		case 'P':
168			cp = optarg;
169			if (cp != NULL && strlen(cp) > 0 &&
170			    strlen(cp) < sizeof (princname)) {
171				if (strchr(cp, '@') == NULL &&
172				    myfqdnname != NULL)
173					snprintf(princname, sizeof (princname),
174					    "%s@%s", cp, myfqdnname);
175				else
176					strlcpy(princname, cp,
177					    sizeof (princname));
178			} else {
179				warnx("client princ invalid. ignored\n");
180			}
181			break;
182		default:
183		case '?':
184			usage();
185		};
186	argv += optind;
187	argc -= optind;
188
189	if (argc > 0)
190		usage();
191
192	if (mustfreeai)
193		freeaddrinfo(aip);
194	nfscbdargs2.principal = (const char *)princname;
195	if (debug == 0) {
196		daemon(0, 0);
197		(void)signal(SIGTERM, SIG_IGN);
198		(void)signal(SIGHUP, SIG_IGN);
199		(void)signal(SIGINT, SIG_IGN);
200		(void)signal(SIGQUIT, SIG_IGN);
201	}
202	(void)signal(SIGSYS, nonfs);
203	(void)signal(SIGCHLD, reapchild);
204
205	openlog("nfscbd:", LOG_PID, LOG_DAEMON);
206
207	pid = fork();
208	if (pid < 0) {
209		syslog(LOG_ERR, "fork: %m");
210		nfscbd_exit(1);
211	} else if (pid > 0) {
212		children = pid;
213	} else {
214		(void)signal(SIGUSR1, child_cleanup);
215		setproctitle("server");
216		nfssvc_flag = NFSSVC_NFSCBD;
217		if (nfssvc(nfssvc_flag, &nfscbdargs2) < 0) {
218			syslog(LOG_ERR, "nfssvc: %m");
219			nfscbd_exit(1);
220		}
221		exit(0);
222	}
223	(void)signal(SIGUSR1, cleanup);
224
225	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
226		syslog(LOG_ERR, "can't create udp socket");
227		nfscbd_exit(1);
228	}
229	memset(&inetaddr, 0, sizeof inetaddr);
230	inetaddr.sin_family = AF_INET;
231	inetaddr.sin_addr.s_addr = INADDR_ANY;
232	inetaddr.sin_port = htons(myport);
233	inetaddr.sin_len = sizeof(inetaddr);
234	ret = bind(sock, (struct sockaddr *)&inetaddr, sizeof(inetaddr));
235	/* If bind() fails, this is a restart, so just skip UDP. */
236	if (ret == 0) {
237		len = sizeof(inetaddr);
238		if (getsockname(sock, (struct sockaddr *)&inetaddr, &len) < 0){
239			syslog(LOG_ERR, "can't get bound addr");
240			nfscbd_exit(1);
241		}
242		nfscbdargs.port = ntohs(inetaddr.sin_port);
243		if (nfscbdargs.port != myport) {
244			syslog(LOG_ERR, "BAD PORT#");
245			nfscbd_exit(1);
246		}
247		nfscbdargs.sock = sock;
248		nfscbdargs.name = NULL;
249		nfscbdargs.namelen = 0;
250		if (nfssvc(NFSSVC_CBADDSOCK, &nfscbdargs) < 0) {
251			syslog(LOG_ERR, "can't Add UDP socket");
252			nfscbd_exit(1);
253		}
254	}
255	(void)close(sock);
256
257	/* Now set up the master server socket waiting for tcp connections. */
258	on = 1;
259	FD_ZERO(&sockbits);
260	connect_type_cnt = 0;
261	if ((tcpsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
262		syslog(LOG_ERR, "can't create tcp socket");
263		nfscbd_exit(1);
264	}
265	if (setsockopt(tcpsock,
266	    SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof(on)) < 0)
267		syslog(LOG_ERR, "setsockopt SO_REUSEADDR: %m");
268	/* sin_port is already set */
269	inetaddr.sin_family = AF_INET;
270	inetaddr.sin_addr.s_addr = INADDR_ANY;
271	inetaddr.sin_port = htons(myport);
272	inetaddr.sin_len = sizeof(inetaddr);
273	if (bind(tcpsock,
274	    (struct sockaddr *)&inetaddr, sizeof (inetaddr)) < 0) {
275		syslog(LOG_ERR, "can't bind tcp addr");
276		nfscbd_exit(1);
277	}
278	if (listen(tcpsock, 5) < 0) {
279		syslog(LOG_ERR, "listen failed");
280		nfscbd_exit(1);
281	}
282	FD_SET(tcpsock, &sockbits);
283	maxsock = tcpsock;
284	connect_type_cnt++;
285
286	setproctitle("master");
287
288	/*
289	 * Loop forever accepting connections and passing the sockets
290	 * into the kernel for the mounts.
291	 */
292	for (;;) {
293		ready = sockbits;
294		if (connect_type_cnt > 1) {
295			if (select(maxsock + 1,
296			    &ready, NULL, NULL, NULL) < 1) {
297				syslog(LOG_ERR, "select failed: %m");
298				nfscbd_exit(1);
299			}
300		}
301		if (FD_ISSET(tcpsock, &ready)) {
302			len = sizeof(inetpeer);
303			if ((msgsock = accept(tcpsock,
304			    (struct sockaddr *)&inetpeer, &len)) < 0) {
305				syslog(LOG_ERR, "accept failed: %m");
306				nfscbd_exit(1);
307			}
308			memset(inetpeer.sin_zero, 0,
309			    sizeof (inetpeer.sin_zero));
310			if (setsockopt(msgsock, SOL_SOCKET,
311			    SO_KEEPALIVE, (char *)&on, sizeof(on)) < 0)
312				syslog(LOG_ERR,
313				    "setsockopt SO_KEEPALIVE: %m");
314			nfscbdargs.sock = msgsock;
315			nfscbdargs.name = (caddr_t)&inetpeer;
316			nfscbdargs.namelen = sizeof(inetpeer);
317			nfssvc(NFSSVC_CBADDSOCK, &nfscbdargs);
318			(void)close(msgsock);
319		}
320	}
321}
322
323void
324usage(void)
325{
326
327	errx(1, "usage: nfscbd %s", USAGE);
328}
329
330void
331nonfs(int signo)
332{
333	syslog(LOG_ERR, "missing system call: NFS not available");
334}
335
336void
337reapchild(int signo)
338{
339	pid_t pid;
340	int i;
341
342	while ((pid = wait3(NULL, WNOHANG, NULL)) > 0) {
343		if (pid == children)
344			children = -1;
345	}
346}
347
348void
349killchildren(void)
350{
351	int i;
352
353	if (children > 0)
354		kill(children, SIGKILL);
355}
356
357/*
358 * Cleanup master after SIGUSR1.
359 */
360void
361cleanup(int signo)
362{
363	nfscbd_exit(0);
364}
365
366/*
367 * Cleanup child after SIGUSR1.
368 */
369void
370child_cleanup(int signo)
371{
372	exit(0);
373}
374
375void
376nfscbd_exit(int status)
377{
378	killchildren();
379	exit(status);
380}
381