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