xref: /freebsd/usr.bin/systat/netstat.c (revision 586f63035fbe5e45cfc971037fd76375661ece26) 
1 /*-
2  * Copyright (c) 1980, 1992, 1993
3  *	The Regents of the University of California.  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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 
32 __FBSDID("$FreeBSD$");
33 
34 #ifdef lint
35 static const char sccsid[] = "@(#)netstat.c	8.1 (Berkeley) 6/6/93";
36 #endif
37 
38 /*
39  * netstat
40  */
41 #include <sys/param.h>
42 #include <sys/queue.h>
43 #include <sys/socket.h>
44 #include <sys/socketvar.h>
45 #include <sys/protosw.h>
46 
47 #include <netinet/in.h>
48 #include <arpa/inet.h>
49 #include <net/route.h>
50 #include <netinet/in_systm.h>
51 #include <netinet/ip.h>
52 #ifdef INET6
53 #include <netinet/ip6.h>
54 #endif
55 #include <netinet/in_pcb.h>
56 #include <netinet/ip_icmp.h>
57 #include <netinet/icmp_var.h>
58 #include <netinet/ip_var.h>
59 #include <netinet/tcp.h>
60 #include <netinet/tcpip.h>
61 #include <netinet/tcp_seq.h>
62 #include <netinet/tcp_var.h>
63 #define TCPSTATES
64 #include <netinet/tcp_fsm.h>
65 #include <netinet/tcp_timer.h>
66 #include <netinet/tcp_debug.h>
67 #include <netinet/udp.h>
68 #include <netinet/udp_var.h>
69 
70 #include <netdb.h>
71 #include <nlist.h>
72 #include <paths.h>
73 #include <stdlib.h>
74 #include <string.h>
75 
76 #include "systat.h"
77 #include "extern.h"
78 
79 static struct netinfo *enter(struct inpcb *, int, const char *);
80 static void enter_kvm(struct inpcb *, struct socket *, int, const char *);
81 static void enter_sysctl(struct inpcb *, struct xsocket *, int, const char *);
82 static void fetchnetstat_kvm(void);
83 static void fetchnetstat_sysctl(void);
84 static char *inetname(struct sockaddr *);
85 static void inetprint(struct sockaddr *, const char *);
86 
87 #define	streq(a,b)	(strcmp(a,b)==0)
88 #define	YMAX(w)		((w)->_maxy-1)
89 
90 WINDOW *
91 opennetstat(void)
92 {
93 	sethostent(1);
94 	setnetent(1);
95 	return (subwin(stdscr, LINES-3-1, 0, MAINWIN_ROW, 0));
96 }
97 
98 struct netinfo {
99 	TAILQ_ENTRY(netinfo) chain;
100 	short	ni_line;		/* line on screen */
101 	short	ni_seen;		/* 0 when not present in list */
102 	short	ni_flags;
103 #define	NIF_LACHG	0x1		/* local address changed */
104 #define	NIF_FACHG	0x2		/* foreign address changed */
105 	short	ni_state;		/* tcp state */
106 	const char	*ni_proto;		/* protocol */
107 	struct sockaddr_storage ni_lsa;	/* local address */
108 	struct sockaddr_storage	ni_fsa;	/* foreign address */
109 	u_int	ni_rcvcc;		/* rcv buffer character count */
110 	u_int	ni_sndcc;		/* snd buffer character count */
111 };
112 
113 TAILQ_HEAD(netinfohead, netinfo) netcb = TAILQ_HEAD_INITIALIZER(netcb);
114 
115 static	int aflag = 0;
116 static	int nflag = 0;
117 static	int lastrow = 1;
118 
119 void
120 closenetstat(WINDOW *w)
121 {
122 	struct netinfo *p;
123 
124 	endhostent();
125 	endnetent();
126 	TAILQ_FOREACH(p, &netcb, chain) {
127 		if (p->ni_line != -1)
128 			lastrow--;
129 		p->ni_line = -1;
130 	}
131 	if (w != NULL) {
132 		wclear(w);
133 		wrefresh(w);
134 		delwin(w);
135 	}
136 }
137 
138 static const char *miblist[] = {
139 	"net.inet.tcp.pcblist",
140 	"net.inet.udp.pcblist"
141 };
142 
143 static char tcb[] = "tcb", udb[] = "udb";
144 
145 struct nlist namelist[] = {
146 #define	X_TCB	0
147 	{ .n_name = tcb },
148 #define	X_UDB	1
149 	{ .n_name = udb },
150 	{ .n_name = NULL },
151 };
152 
153 int
154 initnetstat(void)
155 {
156 	protos = TCP|UDP;
157 	return(1);
158 }
159 
160 void
161 fetchnetstat(void)
162 {
163 	if (use_kvm)
164 		fetchnetstat_kvm();
165 	else
166 		fetchnetstat_sysctl();
167 }
168 
169 static void
170 fetchnetstat_kvm(void)
171 {
172 	struct inpcb *next;
173 	struct netinfo *p;
174 	struct inpcbhead head;
175 	struct inpcb inpcb;
176 	struct socket sockb;
177 	struct tcpcb tcpcb;
178 	void *off;
179 	int istcp;
180 
181 	if (namelist[X_TCB].n_value == 0)
182 		return;
183 	TAILQ_FOREACH(p, &netcb, chain)
184 		p->ni_seen = 0;
185 	if (protos&TCP) {
186 		off = NPTR(X_TCB);
187 		istcp = 1;
188 	}
189 	else if (protos&UDP) {
190 		off = NPTR(X_UDB);
191 		istcp = 0;
192 	}
193 	else {
194 		error("No protocols to display");
195 		return;
196 	}
197 again:
198 	KREAD(off, &head, sizeof (struct inpcbhead));
199 	LIST_FOREACH(next, &head, inp_list) {
200 		KREAD(next, &inpcb, sizeof (inpcb));
201 		next = &inpcb;
202 		if (!aflag) {
203 			if (inpcb.inp_vflag & INP_IPV4) {
204 				if (inet_lnaof(inpcb.inp_laddr) == INADDR_ANY)
205 					continue;
206 			}
207 #ifdef INET6
208 			else if (inpcb.inp_vflag & INP_IPV6) {
209 				if (memcmp(&inpcb.in6p_laddr,
210 				    &in6addr_any, sizeof(in6addr_any)) == 0)
211 					continue;
212 			}
213 #endif
214 		}
215 		if (nhosts && !checkhost(&inpcb))
216 			continue;
217 		if (nports && !checkport(&inpcb))
218 			continue;
219 		if (istcp) {
220 			if (inpcb.inp_flags & INP_TIMEWAIT) {
221 				bzero(&sockb, sizeof(sockb));
222 				enter_kvm(&inpcb, &sockb, TCPS_TIME_WAIT,
223 					 "tcp");
224 			} else {
225 				KREAD(inpcb.inp_socket, &sockb,
226 					sizeof (sockb));
227 				KREAD(inpcb.inp_ppcb, &tcpcb, sizeof (tcpcb));
228 				enter_kvm(&inpcb, &sockb, tcpcb.t_state,
229 					"tcp");
230 			}
231 		} else
232 			enter_kvm(&inpcb, &sockb, 0, "udp");
233 	}
234 	if (istcp && (protos&UDP)) {
235 		istcp = 0;
236 		off = NPTR(X_UDB);
237 		goto again;
238 	}
239 }
240 
241 static void
242 fetchnetstat_sysctl(void)
243 {
244 	struct netinfo *p;
245 	int idx;
246 	struct xinpgen *inpg;
247 	char *cur, *end;
248 	struct inpcb *inpcb;
249 	struct xinpcb *xip = NULL;
250 	struct xtcpcb *xtp = NULL;
251 	int plen;
252 	size_t lsz;
253 
254 	TAILQ_FOREACH(p, &netcb, chain)
255 		p->ni_seen = 0;
256 	if (protos&TCP) {
257 		idx = 0;
258 	} else if (protos&UDP) {
259 		idx = 1;
260 	} else {
261 		error("No protocols to display");
262 		return;
263 	}
264 
265 	for (;idx < 2; idx++) {
266 		if (idx == 1 && !(protos&UDP))
267 			break;
268 		inpg = (struct xinpgen *)sysctl_dynread(miblist[idx], &lsz);
269 		if (inpg == NULL) {
270 			error("sysctl(%s...) failed", miblist[idx]);
271 			continue;
272 		}
273 		/*
274 		 * We currently do no require a consistent pcb list.
275 		 * Try to be robust in case of struct size changes
276 		 */
277 		cur = ((char *)inpg) + inpg->xig_len;
278 		/* There is also a trailing struct xinpgen */
279 		end = ((char *)inpg) + lsz - inpg->xig_len;
280 		if (end <= cur) {
281 			free(inpg);
282 			continue;
283 		}
284 		if (idx == 0) { /* TCP */
285 			xtp = (struct xtcpcb *)cur;
286 			plen = xtp->xt_len;
287 		} else {
288 			xip = (struct xinpcb *)cur;
289 			plen = xip->xi_len;
290 		}
291 		while (cur + plen <= end) {
292 			if (idx == 0) { /* TCP */
293 				xtp = (struct xtcpcb *)cur;
294 				inpcb = &xtp->xt_inp;
295 			} else {
296 				xip = (struct xinpcb *)cur;
297 				inpcb = &xip->xi_inp;
298 			}
299 			cur += plen;
300 
301 			if (!aflag) {
302 				if (inpcb->inp_vflag & INP_IPV4) {
303 					if (inet_lnaof(inpcb->inp_laddr) ==
304 					    INADDR_ANY)
305 						continue;
306 				}
307 #ifdef INET6
308 				else if (inpcb->inp_vflag & INP_IPV6) {
309 					if (memcmp(&inpcb->in6p_laddr,
310 					    &in6addr_any, sizeof(in6addr_any))
311 					    == 0)
312 						continue;
313 				}
314 #endif
315 			}
316 			if (nhosts && !checkhost(inpcb))
317 				continue;
318 			if (nports && !checkport(inpcb))
319 				continue;
320 			if (idx == 0)	/* TCP */
321 				enter_sysctl(inpcb, &xtp->xt_socket,
322 				    xtp->xt_tp.t_state, "tcp");
323 			else		/* UDP */
324 				enter_sysctl(inpcb, &xip->xi_socket, 0, "udp");
325 		}
326 		free(inpg);
327 	}
328 }
329 
330 static void
331 enter_kvm(struct inpcb *inp, struct socket *so, int state, const char *proto)
332 {
333 	struct netinfo *p;
334 
335 	if ((p = enter(inp, state, proto)) != NULL) {
336 		p->ni_rcvcc = so->so_rcv.sb_cc;
337 		p->ni_sndcc = so->so_snd.sb_cc;
338 	}
339 }
340 
341 static void
342 enter_sysctl(struct inpcb *inp, struct xsocket *so, int state, const char *proto)
343 {
344 	struct netinfo *p;
345 
346 	if ((p = enter(inp, state, proto)) != NULL) {
347 		p->ni_rcvcc = so->so_rcv.sb_cc;
348 		p->ni_sndcc = so->so_snd.sb_cc;
349 	}
350 }
351 
352 
353 static struct netinfo *
354 enter(struct inpcb *inp, int state, const char *proto)
355 {
356 	struct netinfo *p;
357 	struct sockaddr_storage lsa, fsa;
358 	struct sockaddr_in *sa4;
359 #ifdef INET6
360 	struct sockaddr_in6 *sa6;
361 #endif
362 
363 	memset(&lsa, 0, sizeof(lsa));
364 	memset(&fsa, 0, sizeof(fsa));
365 	if (inp->inp_vflag & INP_IPV4) {
366 		sa4 = (struct sockaddr_in *)&lsa;
367 		sa4->sin_addr = inp->inp_laddr;
368 		sa4->sin_port = inp->inp_lport;
369 		sa4->sin_family = AF_INET;
370 		sa4->sin_len = sizeof(struct sockaddr_in);
371 
372 		sa4 = (struct sockaddr_in *)&fsa;
373 		sa4->sin_addr = inp->inp_faddr;
374 		sa4->sin_port = inp->inp_fport;
375 		sa4->sin_family = AF_INET;
376 		sa4->sin_len = sizeof(struct sockaddr_in);
377 	}
378 #ifdef INET6
379 	else if (inp->inp_vflag & INP_IPV6) {
380 		sa6 = (struct sockaddr_in6 *)&lsa;
381 		memcpy(&sa6->sin6_addr, &inp->in6p_laddr,
382 		    sizeof(struct in6_addr));
383 		sa6->sin6_port = inp->inp_lport;
384 		sa6->sin6_family = AF_INET6;
385 		sa6->sin6_len = sizeof(struct sockaddr_in6);
386 
387 		sa6 = (struct sockaddr_in6 *)&fsa;
388 		memcpy(&sa6->sin6_addr, &inp->in6p_faddr,
389 		    sizeof(struct in6_addr));
390 		sa6->sin6_port = inp->inp_fport;
391 		sa6->sin6_family = AF_INET6;
392 		sa6->sin6_len = sizeof(struct sockaddr_in6);
393 	}
394 #endif
395 	else
396 		return NULL;
397 
398 	/*
399 	 * Only take exact matches, any sockets with
400 	 * previously unbound addresses will be deleted
401 	 * below in the display routine because they
402 	 * will appear as ``not seen'' in the kernel
403 	 * data structures.
404 	 */
405 	TAILQ_FOREACH(p, &netcb, chain) {
406 		if (!streq(proto, p->ni_proto))
407 			continue;
408 		if (p->ni_lsa.ss_family != lsa.ss_family ||
409 		    memcmp(&p->ni_lsa, &lsa, lsa.ss_len) != 0)
410 			continue;
411 		if (p->ni_fsa.ss_family == fsa.ss_family &&
412 		    memcmp(&p->ni_fsa, &fsa, fsa.ss_len) == 0)
413 			break;
414 	}
415 	if (p == NULL) {
416 		if ((p = malloc(sizeof(*p))) == NULL) {
417 			error("Out of memory");
418 			return NULL;
419 		}
420 		TAILQ_INSERT_HEAD(&netcb, p, chain);
421 		p->ni_line = -1;
422 		memcpy(&p->ni_lsa, &lsa, lsa.ss_len);
423 		memcpy(&p->ni_fsa, &fsa, fsa.ss_len);
424 		p->ni_proto = strdup(proto);
425 		p->ni_flags = NIF_LACHG|NIF_FACHG;
426 	}
427 	p->ni_state = state;
428 	p->ni_seen = 1;
429 	return p;
430 }
431 
432 /* column locations */
433 #define	LADDR	0
434 #define	FADDR	LADDR+23
435 #define	PROTO	FADDR+23
436 #define	RCVCC	PROTO+6
437 #define	SNDCC	RCVCC+7
438 #define	STATE	SNDCC+7
439 
440 
441 void
442 labelnetstat(void)
443 {
444 	if (use_kvm && namelist[X_TCB].n_type == 0)
445 		return;
446 	wmove(wnd, 0, 0); wclrtobot(wnd);
447 	mvwaddstr(wnd, 0, LADDR, "Local Address");
448 	mvwaddstr(wnd, 0, FADDR, "Foreign Address");
449 	mvwaddstr(wnd, 0, PROTO, "Proto");
450 	mvwaddstr(wnd, 0, RCVCC, "Recv-Q");
451 	mvwaddstr(wnd, 0, SNDCC, "Send-Q");
452 	mvwaddstr(wnd, 0, STATE, "(state)");
453 }
454 
455 void
456 shownetstat(void)
457 {
458 	struct netinfo *p, *q;
459 	char proto[6];
460 	const char *family = "";
461 
462 	/*
463 	 * First, delete any connections that have gone
464 	 * away and adjust the position of connections
465 	 * below to reflect the deleted line.
466 	 */
467 	p = TAILQ_FIRST(&netcb);
468 	while (p != NULL) {
469 		if (p->ni_line == -1 || p->ni_seen) {
470 			p = TAILQ_NEXT(p, chain);
471 			continue;
472 		}
473 		wmove(wnd, p->ni_line, 0); wdeleteln(wnd);
474 		TAILQ_FOREACH(q, &netcb, chain)
475 			if (q != p && q->ni_line > p->ni_line) {
476 				q->ni_line--;
477 				/* this shouldn't be necessary */
478 				q->ni_flags |= NIF_LACHG|NIF_FACHG;
479 			}
480 		lastrow--;
481 		q = TAILQ_NEXT(p, chain);
482 		TAILQ_REMOVE(&netcb, p, chain);
483 		free(p);
484 		p = q;
485 	}
486 	/*
487 	 * Update existing connections and add new ones.
488 	 */
489 	TAILQ_FOREACH(p, &netcb, chain) {
490 		if (p->ni_line == -1) {
491 			/*
492 			 * Add a new entry if possible.
493 			 */
494 			if (lastrow > YMAX(wnd))
495 				continue;
496 			p->ni_line = lastrow++;
497 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
498 		}
499 		if (p->ni_flags & NIF_LACHG) {
500 			wmove(wnd, p->ni_line, LADDR);
501 			inetprint((struct sockaddr *)&p->ni_lsa, p->ni_proto);
502 			p->ni_flags &= ~NIF_LACHG;
503 		}
504 		if (p->ni_flags & NIF_FACHG) {
505 			wmove(wnd, p->ni_line, FADDR);
506 			inetprint((struct sockaddr *)&p->ni_fsa, p->ni_proto);
507 			p->ni_flags &= ~NIF_FACHG;
508 		}
509 #ifdef INET6
510 		family = (p->ni_lsa.ss_family == AF_INET) ? "4" : "6";
511 #endif
512 		snprintf(proto, sizeof(proto), "%s%s", p->ni_proto, family);
513 		mvwaddstr(wnd, p->ni_line, PROTO, proto);
514 		mvwprintw(wnd, p->ni_line, RCVCC, "%6u", p->ni_rcvcc);
515 		mvwprintw(wnd, p->ni_line, SNDCC, "%6u", p->ni_sndcc);
516 		if (streq(p->ni_proto, "tcp")) {
517 			if (p->ni_state < 0 || p->ni_state >= TCP_NSTATES)
518 				mvwprintw(wnd, p->ni_line, STATE, "%d",
519 				    p->ni_state);
520 			else
521 				mvwaddstr(wnd, p->ni_line, STATE,
522 				    tcpstates[p->ni_state]);
523 		}
524 		wclrtoeol(wnd);
525 	}
526 	if (lastrow < YMAX(wnd)) {
527 		wmove(wnd, lastrow, 0); wclrtobot(wnd);
528 		wmove(wnd, YMAX(wnd), 0); wdeleteln(wnd);	/* XXX */
529 	}
530 }
531 
532 /*
533  * Pretty print an Internet address (net address + port).
534  * If the nflag was specified, use numbers instead of names.
535  */
536 static void
537 inetprint(struct sockaddr *sa, const char *proto)
538 {
539 	struct servent *sp = 0;
540 	char line[80], *cp;
541 	int port;
542 
543 	switch (sa->sa_family) {
544 	case AF_INET:
545 		port = ((struct sockaddr_in *)sa)->sin_port;
546 		break;
547 #ifdef INET6
548 	case AF_INET6:
549 		port = ((struct sockaddr_in6 *)sa)->sin6_port;
550 		break;
551 #endif
552 	default:
553 		port = 0;
554 		break;
555 	}
556 	snprintf(line, sizeof(line), "%.*s.", 16, inetname(sa));
557 	cp = index(line, '\0');
558 	if (!nflag && port)
559 		sp = getservbyport(port, proto);
560 	if (sp || port == 0)
561 		snprintf(cp, sizeof(line) - (cp - line), "%.8s",
562 		    sp ? sp->s_name : "*");
563 	else
564 		snprintf(cp, sizeof(line) - (cp - line), "%d",
565 		    ntohs((u_short)port));
566 	/* pad to full column to clear any garbage */
567 	cp = index(line, '\0');
568 	while (cp - line < 22)
569 		*cp++ = ' ';
570 	line[22] = '\0';
571 	waddstr(wnd, line);
572 }
573 
574 /*
575  * Construct an Internet address representation.
576  * If the nflag has been supplied, give
577  * numeric value, otherwise try for symbolic name.
578  */
579 static char *
580 inetname(struct sockaddr *sa)
581 {
582 	char *cp = 0;
583 	static char line[NI_MAXHOST];
584 	struct hostent *hp;
585 	struct netent *np;
586 	struct in_addr in;
587 
588 #ifdef INET6
589 	if (sa->sa_family == AF_INET6) {
590 		if (memcmp(&((struct sockaddr_in6 *)sa)->sin6_addr,
591 		    &in6addr_any, sizeof(in6addr_any)) == 0)
592 			strcpy(line, "*");
593 		else
594 			getnameinfo(sa, sa->sa_len, line, sizeof(line), NULL, 0,
595 			    nflag ? NI_NUMERICHOST : 0);
596 		return (line);
597 	}
598 #endif
599 
600 	in = ((struct sockaddr_in *)sa)->sin_addr;
601 	if (!nflag && in.s_addr != INADDR_ANY) {
602 		int net = inet_netof(in);
603 		int lna = inet_lnaof(in);
604 
605 		if (lna == INADDR_ANY) {
606 			np = getnetbyaddr(net, AF_INET);
607 			if (np)
608 				cp = np->n_name;
609 		}
610 		if (cp == 0) {
611 			hp = gethostbyaddr((char *)&in, sizeof (in), AF_INET);
612 			if (hp)
613 				cp = hp->h_name;
614 		}
615 	}
616 	if (in.s_addr == INADDR_ANY)
617 		strcpy(line, "*");
618 	else if (cp)
619 		snprintf(line, sizeof(line), "%s", cp);
620 	else {
621 		in.s_addr = ntohl(in.s_addr);
622 #define C(x)	((x) & 0xff)
623 		snprintf(line, sizeof(line), "%u.%u.%u.%u", C(in.s_addr >> 24),
624 			C(in.s_addr >> 16), C(in.s_addr >> 8), C(in.s_addr));
625 	}
626 	return (line);
627 }
628 
629 int
630 cmdnetstat(const char *cmd, const char *args)
631 {
632 	if (prefix(cmd, "all")) {
633 		aflag = !aflag;
634 		goto fixup;
635 	}
636 	if  (prefix(cmd, "numbers") || prefix(cmd, "names")) {
637 		struct netinfo *p;
638 		int new;
639 
640 		new = prefix(cmd, "numbers");
641 		if (new == nflag)
642 			return (1);
643 		TAILQ_FOREACH(p, &netcb, chain) {
644 			if (p->ni_line == -1)
645 				continue;
646 			p->ni_flags |= NIF_LACHG|NIF_FACHG;
647 		}
648 		nflag = new;
649 		goto redisplay;
650 	}
651 	if (!netcmd(cmd, args))
652 		return (0);
653 fixup:
654 	fetchnetstat();
655 redisplay:
656 	shownetstat();
657 	refresh();
658 	return (1);
659 }
660