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/param.h>
29#include <sys/ioctl.h>
30#include <sys/linker.h>
31#include <sys/module.h>
32#include <sys/mount.h>
33#include <sys/socket.h>
34#include <sys/socketvar.h>
35#include <sys/stat.h>
36#include <sys/ucred.h>
37#include <sys/uio.h>
38#include <sys/vnode.h>
39#include <sys/wait.h>
40
41#include <nfs/nfssvc.h>
42
43#include <rpc/rpc.h>
44
45#include <fs/nfs/rpcv2.h>
46#include <fs/nfs/nfsproto.h>
47#include <fs/nfs/nfskpiport.h>
48#include <fs/nfs/nfs.h>
49
50#include <err.h>
51#include <errno.h>
52#include <fcntl.h>
53#include <grp.h>
54#include <netdb.h>
55#include <pwd.h>
56#include <signal.h>
57#include <stdio.h>
58#include <stdlib.h>
59#include <string.h>
60#include <syslog.h>
61#include <unistd.h>
62
63/* Global defs */
64#ifdef DEBUG
65#define	syslog(e, s)	fprintf(stderr,(s))
66static int	debug = 1;
67#else
68static int	debug = 0;
69#endif
70
71static pid_t	children;
72
73static void	nonfs(int);
74static void	reapchild(int);
75static void	usage(void);
76static void	cleanup(int);
77static void	child_cleanup(int);
78static void	nfscbd_exit(int);
79static void	killchildren(void);
80
81/*
82 * Nfs callback server daemon.
83 *
84 * 1 - do file descriptor and signal cleanup
85 * 2 - fork the nfscbd(s)
86 * 4 - create callback server socket(s)
87 * 5 - set up server socket for rpc
88 *
89 * For connectionless protocols, just pass the socket into the kernel via.
90 * nfssvc().
91 * For connection based sockets, loop doing accepts. When you get a new
92 * socket from accept, pass the msgsock into the kernel via. nfssvc().
93 */
94int
95main(int argc, char *argv[])
96{
97	struct nfscbd_args nfscbdargs;
98	struct nfsd_nfscbd_args nfscbdargs2;
99	struct sockaddr_in inetaddr, inetpeer;
100	fd_set ready, sockbits;
101	int ch, connect_type_cnt, maxsock, msgsock, error;
102	int nfssvc_flag, on, sock, tcpsock, ret, mustfreeai = 0;
103	char *cp, princname[128];
104	char myname[MAXHOSTNAMELEN], *myfqdnname = NULL;
105	struct addrinfo *aip, hints;
106	pid_t pid;
107	short myport = NFSV4_CBPORT;
108	socklen_t len;
109
110	if (modfind("nfscl") < 0) {
111		/* Not present in kernel, try loading it */
112		if (kldload("nfscl") < 0 ||
113		    modfind("nfscl") < 0)
114			errx(1, "nfscl is not available");
115	}
116	/*
117	 * First, get our fully qualified host name, if possible.
118	 */
119	if (gethostname(myname, MAXHOSTNAMELEN) >= 0) {
120		cp = strchr(myname, '.');
121		if (cp != NULL && *(cp + 1) != '\0') {
122			cp = myname;
123		} else {
124			/*
125			 * No domain on myname, so try looking it up.
126			 */
127			cp = NULL;
128			memset((void *)&hints, 0, sizeof (hints));
129			hints.ai_flags = AI_CANONNAME;
130			error = getaddrinfo(myname, NULL, &hints, &aip);
131			if (error == 0) {
132			    if (aip->ai_canonname != NULL &&
133				(cp = strchr(aip->ai_canonname, '.')) != NULL
134				&& *(cp + 1) != '\0') {
135				    cp = aip->ai_canonname;
136				    mustfreeai = 1;
137			    } else {
138				    freeaddrinfo(aip);
139			    }
140			}
141		}
142		if (cp == NULL)
143			warnx("Can't get fully qualified host name");
144		myfqdnname = cp;
145	}
146
147	princname[0] = '\0';
148#define	GETOPT	"p:P:"
149#define	USAGE	"[ -p port_num ] [ -P client_principal ]"
150	while ((ch = getopt(argc, argv, GETOPT)) != -1)
151		switch (ch) {
152		case 'p':
153			myport = atoi(optarg);
154			if (myport < 1) {
155				warnx("port# non-positive, reset to %d",
156				    NFSV4_CBPORT);
157				myport = NFSV4_CBPORT;
158			}
159			break;
160		case 'P':
161			cp = optarg;
162			if (cp != NULL && strlen(cp) > 0 &&
163			    strlen(cp) < sizeof (princname)) {
164				if (strchr(cp, '@') == NULL &&
165				    myfqdnname != NULL)
166					snprintf(princname, sizeof (princname),
167					    "%s@%s", cp, myfqdnname);
168				else
169					strlcpy(princname, cp,
170					    sizeof (princname));
171			} else {
172				warnx("client princ invalid. ignored\n");
173			}
174			break;
175		default:
176		case '?':
177			usage();
178		}
179	argv += optind;
180	argc -= optind;
181
182	if (argc > 0)
183		usage();
184
185	if (mustfreeai)
186		freeaddrinfo(aip);
187	nfscbdargs2.principal = (const char *)princname;
188	if (debug == 0) {
189		daemon(0, 0);
190		(void)signal(SIGTERM, SIG_IGN);
191		(void)signal(SIGHUP, SIG_IGN);
192		(void)signal(SIGINT, SIG_IGN);
193		(void)signal(SIGQUIT, SIG_IGN);
194	}
195	(void)signal(SIGSYS, nonfs);
196	(void)signal(SIGCHLD, reapchild);
197
198	openlog("nfscbd:", LOG_PID, LOG_DAEMON);
199
200	pid = fork();
201	if (pid < 0) {
202		syslog(LOG_ERR, "fork: %m");
203		nfscbd_exit(1);
204	} else if (pid > 0) {
205		children = pid;
206	} else {
207		(void)signal(SIGUSR1, child_cleanup);
208		setproctitle("server");
209		nfssvc_flag = NFSSVC_NFSCBD;
210		if (nfssvc(nfssvc_flag, &nfscbdargs2) < 0) {
211			syslog(LOG_ERR, "nfssvc: %m");
212			nfscbd_exit(1);
213		}
214		exit(0);
215	}
216	(void)signal(SIGUSR1, cleanup);
217
218	if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
219		syslog(LOG_ERR, "can't create udp socket");
220		nfscbd_exit(1);
221	}
222	memset(&inetaddr, 0, sizeof inetaddr);
223	inetaddr.sin_family = AF_INET;
224	inetaddr.sin_addr.s_addr = INADDR_ANY;
225	inetaddr.sin_port = htons(myport);
226	inetaddr.sin_len = sizeof(inetaddr);
227	ret = bind(sock, (struct sockaddr *)&inetaddr, sizeof(inetaddr));
228	/* If bind() fails, this is a restart, so just skip UDP. */
229	if (ret == 0) {
230		len = sizeof(inetaddr);
231		if (getsockname(sock, (struct sockaddr *)&inetaddr, &len) < 0){
232			syslog(LOG_ERR, "can't get bound addr");
233			nfscbd_exit(1);
234		}
235		nfscbdargs.port = ntohs(inetaddr.sin_port);
236		if (nfscbdargs.port != myport) {
237			syslog(LOG_ERR, "BAD PORT#");
238			nfscbd_exit(1);
239		}
240		nfscbdargs.sock = sock;
241		nfscbdargs.name = NULL;
242		nfscbdargs.namelen = 0;
243		if (nfssvc(NFSSVC_CBADDSOCK, &nfscbdargs) < 0) {
244			syslog(LOG_ERR, "can't Add UDP socket");
245			nfscbd_exit(1);
246		}
247	}
248	(void)close(sock);
249
250	/* Now set up the master server socket waiting for tcp connections. */
251	on = 1;
252	FD_ZERO(&sockbits);
253	connect_type_cnt = 0;
254	if ((tcpsock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
255		syslog(LOG_ERR, "can't create tcp socket");
256		nfscbd_exit(1);
257	}
258	if (setsockopt(tcpsock,
259	    SOL_SOCKET, SO_REUSEADDR, (char *)&on, sizeof(on)) < 0)
260		syslog(LOG_ERR, "setsockopt SO_REUSEADDR: %m");
261	/* sin_port is already set */
262	inetaddr.sin_family = AF_INET;
263	inetaddr.sin_addr.s_addr = INADDR_ANY;
264	inetaddr.sin_port = htons(myport);
265	inetaddr.sin_len = sizeof(inetaddr);
266	if (bind(tcpsock,
267	    (struct sockaddr *)&inetaddr, sizeof (inetaddr)) < 0) {
268		syslog(LOG_ERR, "can't bind tcp addr");
269		nfscbd_exit(1);
270	}
271	if (listen(tcpsock, 5) < 0) {
272		syslog(LOG_ERR, "listen failed");
273		nfscbd_exit(1);
274	}
275	FD_SET(tcpsock, &sockbits);
276	maxsock = tcpsock;
277	connect_type_cnt++;
278
279	setproctitle("master");
280
281	/*
282	 * Loop forever accepting connections and passing the sockets
283	 * into the kernel for the mounts.
284	 */
285	for (;;) {
286		ready = sockbits;
287		if (connect_type_cnt > 1) {
288			if (select(maxsock + 1,
289			    &ready, NULL, NULL, NULL) < 1) {
290				syslog(LOG_ERR, "select failed: %m");
291				nfscbd_exit(1);
292			}
293		}
294		if (FD_ISSET(tcpsock, &ready)) {
295			len = sizeof(inetpeer);
296			if ((msgsock = accept(tcpsock,
297			    (struct sockaddr *)&inetpeer, &len)) < 0) {
298				syslog(LOG_ERR, "accept failed: %m");
299				nfscbd_exit(1);
300			}
301			memset(inetpeer.sin_zero, 0,
302			    sizeof (inetpeer.sin_zero));
303			if (setsockopt(msgsock, SOL_SOCKET,
304			    SO_KEEPALIVE, (char *)&on, sizeof(on)) < 0)
305				syslog(LOG_ERR,
306				    "setsockopt SO_KEEPALIVE: %m");
307			nfscbdargs.sock = msgsock;
308			nfscbdargs.name = (caddr_t)&inetpeer;
309			nfscbdargs.namelen = sizeof(inetpeer);
310			nfssvc(NFSSVC_CBADDSOCK, &nfscbdargs);
311			(void)close(msgsock);
312		}
313	}
314}
315
316static void
317usage(void)
318{
319
320	errx(1, "usage: nfscbd %s", USAGE);
321}
322
323static void
324nonfs(int signo __unused)
325{
326	syslog(LOG_ERR, "missing system call: NFS not available");
327}
328
329static void
330reapchild(int signo __unused)
331{
332	pid_t pid;
333
334	while ((pid = wait3(NULL, WNOHANG, NULL)) > 0) {
335		if (pid == children)
336			children = -1;
337	}
338}
339
340static void
341killchildren(void)
342{
343
344	if (children > 0)
345		kill(children, SIGKILL);
346}
347
348/*
349 * Cleanup master after SIGUSR1.
350 */
351static void
352cleanup(int signo __unused)
353{
354	nfscbd_exit(0);
355}
356
357/*
358 * Cleanup child after SIGUSR1.
359 */
360static void
361child_cleanup(int signo __unused)
362{
363	exit(0);
364}
365
366static void
367nfscbd_exit(int status __unused)
368{
369	killchildren();
370	exit(status);
371}
372